Artículos de revistas sobre el tema "OH point defects"

Abstract. Research results of the past 6 decades on the incorporation of OH point defects in quartz are summarised and evaluated in terms of their application to natural samples and processes, and a link between experimental petrology, natural archives, and model calculations is made. A strong focus is put on recent studies on quartz as a rock-forming mineral, as a geochemical and/or petrological tracer, and as a tool for provenance analysis in sediments and sedimentary rocks. The most relevant defects for natural specimens are generated by coupled substitution involving mono- and trivalent cations, the most prominent being Li+, Al3+, and B3+. OH incorporation is rather a function of the availability of trace metals and water than of pressure and temperature, though temperature indirectly influences the incorporation by the solubility of trace metals in the fluid. Pressure has a negative influence on the formation of OH defects, so the most pure quartzes are probably formed in the deep crust close to the quartz/coesite transition. Natural quartz grains from the Earth's crust have on average 10 wt ppm (weight parts per million) water (5 wt ppm median), but grains with OH defect contents corresponding to up 250 wt ppm water have been discovered in sedimentary archives, matching the concentration of quartz from high-pressure experiments <4 kbar under water-saturated conditions in granitic systems. A rough division into three classes is suggested: (1) grains with pristine igneous and/or hydrothermal origin, (2) mildly thermally annealed grains, and (3) strongly dehydrated grains. While samples derived from the currently exposed Scandinavian Shield are dominated by the third class, considerable contributions of the first two classes are found in the younger rock systems in Central Europe. OH defect contents may be used to estimate mixing ratios for sediments with different sources, provided that a sufficiently large data set exists and that the different sources can be clearly distinguished by their OH inventory. Furthermore, metamorphic overprint leads to a higher degree of equilibration of OH defects between individual grains and may thus be used as a geothermometer. Finally, OH defect retention in quartz allows for estimating timescales of volcanic processes.

AbstractWe have performed studies of the structural and electronic properties of functionalized single wall silicon carbide nanotubes (SW-SiCNTs) with chirality (5,5). Our first principles studies are done using density functional theory. The exchange-correlation energies are modeled according to the Hamprecht-Cohen-Tozer-Handy functional in the generalized gradient approximation (HCTH-GGA) and the DNP basis function with double polarization is applied. To determine the most stable geometry, we have applied the minimum energy criterion considering several initial configurations of the hydroxyl (OH) functional group interacting with the single wall SiCNT. In particular, we tested different orientations of the OH adsorbed on the nanotube surface (oriented towards the Si or C atoms) and at the end of the nanotube. Results indicate that the most favorable geometry corresponds to OH adsorption (chemisorption) at the end of the nanotube. The polarity increases yielding better conditions for solubility and dispersion. The work function of the SW-SiCNT-OH is reduced, which in turn favors conditions for field emission properties (FEPs). Finally, the presence of silicon or carbon mono-vacancies in the functionalized nanotubes suggests this may be a good structure to fabricate semiconductor devices

The analysis of structural particularities of nominally pure and doped LiNbO3single crystals was performed by methods of Raman light scattering and infrared absorption. The concentration of OH groups, as well as the concentration of point defects is calculated from IR absorption spectra in the region of stretching vibrations of OH groups. A correlation has been determined in behavior of IR absorption spectra bands of strongly doped LiNbO3:Zn crystals with the behavior of the Raman spectra band that correspondsto stretching bridge vibrations of oxygen atoms in octahedra along the polar axis.

AbstractA defect structure and osseointegration capacity of sodium and chloride co-substituted hydroxyapatite (NaClAp) were newly studied. The NaClAp was prepared by reacting H3PO4 and Ca(OH)2 with NaNO3 and NH4Cl followed by sintering; pure hydroxyapatite (HAp) was synthesized as a control. After sintering, the co-substitution of Ca and OH with Na and Cl, respectively, produced charged point defects at Ca and PO4 sites. Also, OH molecules partially adopted a head-on structure. The calculated total system energy of NaClAp was higher, whereas the binding energies between each constituent elements and system were lower than those of HAp. These results suggest that NaClAp was less stable than HAp, due to the formation of various defects by co-substitution of Na and Cl. Indeed, NaClAp exhibited higher dissolution behavior in simulated body fluid (SBF) compared with HAp. Accordingly, this increased the capability to produce low crystalline hydroxyl carbonate apatite, likely due to the increasing degree of apatite supersaturation in SBF. Besides, the NaClAp granules showed noticeable improvements in osseointegration capacity four weeks after in vivo test compared with HAp. Collectively, these results imply that the defects made by multiple ion substitutions are useful to increase osseointegration capacity of hydroxyapatite.

Photoluminescence was studied in the volume of congruent and near-stoichiometric lithium niobate crystals obtained by different technologies. Luminescence intensity in near-stoichiometric crystals was found to be lower than that in a congruent crystal. We have shown that not only basic centers (caused by point defects NbLi, VLi) contribute to luminescence, but also complex defects caused by existence of OH-groups.

The photoluminescence intensity in lithium niobate crystals close to the stoichiometric composition being lower than in a congruent crystal was established. The increase of Li / Nb ratio leads to shifting the photoluminescence bands to the short-wavelength region of the spectrum and changing the fundamental absorption edge of the crystals under study. It was shown that, in addition to point defects in the cationic sublattice, complex defects due to the presence of OH groups and compensation defects (VLi / VNb) in the structure can also contribute to photoluminescence.

Исследованы ИК-спектры поглощения в области валентных колебаний OH - групп кристаллов ниобата лития стехиометрического и конгруэнтного составов. Рассчитана концентрация OH - групп, отношение Li / Nb, а также концентрация точечных дефектов Nb и V. Результаты расчетов совпадают с литературными данными и подтверждаются фазовой диаграммой ниобата лития. Показано, что увеличение количества свободных протонов (вносящих вклад в проводимость) может обуславливать более высокие электропроводность, скорость термической фиксации голограмм и снижение эффекта фоторефракции. The IR absorption spectra in the region of stretching vibrations of OH - groups of lithium niobate crystals of stoichiometric and congruent compositions are studied. The results of calculations of the OH - groups concentration, the Li / Nb ratio and the concentration of point defects Nb and V coincide with the literature data. The phase diagram of lithium niobate confirms these results. It is shown that an increase in the number of free protons that contribute to conductivity can lead to reducing the optical damage and higher electrical conductivity and the rate of thermal fixation of holograms.

Several methods are available to enhance the healing and regeneration of periodontal tissues after surgical therapy of intrabony defects. The main indications for the use of combined regenerative procedures are the extent and morphology of the osseous lesions. The six studies of the present dissertation focused on the clinical effect of different barrier techniques, bone substitutes, enamel matrix derivatives and a growth factors containing adjuvant used in various combinations on the healing of severe periodontal intrabony impairments. Synthetic, xenogenetic and autologous materials were used in these randomized clinical studies. Mechanical barriers (polytetrafluoroethylene and collagen membranes) for GTR, biological barriers/enamel matrix proteins (EMD), synthetic (β-TCP) and xenogeneic (NBM) bone grafts and autologous platelet-rich plasma (PRP) were combined in the test and control groups of the trials. The main clinical variable was the clinical attachment level (CAL) and the subsidiary one was the probing pocket depth (PPD), estimated at baseline and after one year. The summation of the results after the statistical analysis takes cognizance of the followings: a) Each of the eleven regenerative methods evaluated (ten combined procedures) leads to significant CAL gain and PPD decrease. b) Using β-TCP or NBM with EMD or with PRP + GTR and GTR’s, the difference between the parameters of the test and control groups were not statistically significant. c) It was confirmed in four studies that the addition of PRP to graft materials has not increased significantly the positive outcomes independent of the type of barrier or graft. d) Adding platelet-rich plasma to natural bone mineral, no benefit was observed from the point of view of the clinical variables. e) The polypeptide proteins of the platelet-rich plasma do not enhance the clinical regenerative effect of enamel matrix proteins. In conclusion, the option of the periodontal surgeons between these methods depends mainly on the defect morphology, the patient’s approach to the different types of materials, the medical concept of the physician, the technical possibilities and the clinical experience of the periodontist.

Методом ИК-спектроскопии в области валентных колебаний OH - групп выполнен анализ комплексных дефектов, обусловленных наличием в структуре кристалла водородных связей, в номинально чистых кристаллах ниобата лития конгруэнтного и стехиометрического состава с разным отношением Li / Nb, а также в кристаллах LiNbO: Zn(0,04 - 6,5 мол.% ZnO), легированных цинком в широком диапазоне концентраций, полученным по технологии прямого легирования расплава. Выявлено влияние легирующих примесей на концентрацию OH - групп, вид и локализацию комплексных дефектов в структуре кристалла. Показано, что изменение количества позиций атомов водорода в структуре кристалла LiNbO позволяет с достаточной точностью судить о соответствии его состава стехиометрическому или конгруэнтному составу. Для легированных кристаллов LiNbO : Zn(0,04 - 6,5 мол.% ZnO) получены данные, свидетельствующие об изменении при прохождении концентрационных порогов характера комплексообразования OH - групп с точечными дефектами катионной подрешетки. При этом, вследствие изменения механизма вхождения легирующего катиона в структуру кардинально изменяются свойства кристалла. Вклад в различие частот (и, соответственно, в значение квазиупругих постоянных связей OH -) в спектре конгруэнтного кристалла и легированных кристаллов может вносить также различие электроотрицательностей и ионных радиусов основных и легирующих катионов. An analysis of complex defects was carried out by IR-spectroscopy method in the area of OH - groups stretching vibrations. The defects are caused by hydrogen bonds present in the structure of nominally pure congruent lithium niobate crystals, crystals of stoichiometric composition with a different Li / Nb ratio, as well as in LiNbO: Zn(0,04 - 6,5 мол.% ZnO) crystals doped in a wide range of concentrations due to direct doping of the melt method. Dopants were determined to influence OH - groups concentration, type and localization of complex defects in the crystals structure. A change in the amount of hydrogen sites in the LiNbO crystals structure was shown to evaluate the composition either stoichiometric or congruent. The character of OH - groups complexing with cation sublattice point defects was shown to change when doped crystals LiNbO: Zn(0,04 - 6,5 мол.% ZnO) trespass concentration thresholds. Dopant incorporation mechanism changes at this drastically, thus crystal properties also change quite sharply. Frequencies (as well as quasi-elastic constants of OH - bonds) change in congruent and doped crystals due to a difference in electronegativities and ionic radii of the main and dopant cations.

The photoluminescence intensity in lithium niobate crystals close to the stoichiometric composition is lower than in a congruent crystal was established. An increase in the Li / Nb ratio leads to a shift in the photoluminescence bands to the short-wavelength region of the spectrum and a change in the fundamental absorption edge of the crystals under study. It was shown that, in addition to point defects in the cationic sublattice, complex defects due to the presence of OH groups in the structure can also contribute to photoluminescence.

Infrared absorption measurements have been used to study the radiation response of various hydroxyl point defects present in natural quartz crystals in their unswept, Na-swept, and H-swept conditions for “low-H” and “high-H” samples with similar aluminum concentration. The irradiation was done at 77 K, 300 K, and finally again at 77 K in sequence. At low-temperature irradiation the Al-OH− bands equalize in their intensity-like H-swept or prior 300 K-irradiated cultured quartz. Among other major bands the alkali-related centers show a reduction in their strength at all stages of irradiation. Purely H-related centers show no steady-state room temperature effects; only the low-temperature irradiation reduces their band strength. The results have been discussed in terms of proton and alkali ion motion to shallow and deep traps and compared with cultured quartz.

The concentration of OH groups, the ratio of Li/Nb, as well as the concentration of NbLi4+ and VLi- point defects is calculated from IR absorption spectra in the region of stretching vibrations of OH groups of LiNbO3 crystals. The crystals were of stoichiometric and congruent composition, as well as doped with doped near-threshold concentrations of magnesium and zinc. A correlation has been determined in behavior of IR absorption spectra bands of strongly doped LiNbO3:Mg and LiNbO3:Zn crystals with the behavior of the Raman spectra band that corresponds to stretching bridge vibrations of oxygen atoms in NbO6 octahedra along the polar axis.

We have analyzed complex defects due to the presence of hydrogen bonds in the crystal structure in nominally pure lithium niobate crystals with different Li/Nb ratio, in crystals alloyed with magnesium and zinc in a wide concentration range (LiNbO3 : Mg (0.19-5.91 mol.% MgO) and LiNbO3 : Zn (0.04-6.5 mol. % ZnO)) and in the double-alloyed crystals (LiNbO3 : Y(0.24) : Mg(0.63 wt. %) and LiNbO3 : Gd (0.25) : Mg(0.75 wt. %)), obtained by technology of direct melt alloying, and also in the double-alloyed crystal (LiNbO3 : Mg(5. 05 mol.% MgO) : Fe(0.009 mol.% Fe2O3)) grown from a charge synthesized using the technology of homogeneous alloying with magnesium and iron Nb2O5. We revealed the influence of doping impurities on the concentration of OH-groups, the type and localization of complex defects in the crystal structure. The change in the number of hydrogen atom positions in the structure of the LiNbO3 crystal allow us to judge with sufficient accuracy whether the crystal composition is stoichiometric or congruent. For doped crystals of different compositions data were obtained testifying to changes in the character of complexation of OH-groups with point defects of the cationic sublattice with formation of defects: MеLi-OH-, MеLi-MеNb-OН. A change in the mechanism of entry of the dopant cation into the structure dramatically affects the change in the properties of the crystal.The difference in the frequencies (and, correspondingly, in the values of the quasi-elastic constants of the O-H bonds) in the spectrum of a congruent crystal and doped crystals can also be contributed by differences in the electronegativity and ionic radii of the principal and doping cations.

Signal transmission over optical fibers in the ultraviolet to near-infrared domains remains very challenging due to their high intrinsic losses. In radiation-rich environments, this is made even more difficult due to the radiation-induced attenuation (RIA) phenomenon. We investigated here how the number of hydroxyl groups (OH) present in multi-mode (MM) pure-silica core (PSC) optical fibers influences the RIA levels and kinetics. For this, we tested three different fiber samples: one “wet”, one “dry” and one with an intermediate “medium” OH content. The RIA of the three samples was measured in the 400–900 nm (~3 eV to ~1.4 eV) spectral range during and after an X-ray irradiation at a dose rate of 6 Gy(SiO2) s−1 up to a total accumulated dose of 300 kGy(SiO2). Furthermore, we evaluated the H2-pre-loading efficiency in the medium OH sample to permanently improve both its intrinsic losses and radiation response in the visible domain. Finally, the spectral decomposition of the various RIA responses allows us to better understand the basic mechanisms related to the point defects causing the excess of optical losses. Particularly, it reveals the relationship between the initial OH groups content and the generation of non-bridging oxygen hole centers (NBOHCs). Moreover, the presence of hydroxyl groups also affects the contribution from other intrinsic defects such as the self-trapped holes (STHs) to the RIA in this spectral domain.

Water distribution in the deep Earth represents one of the most important topics in the field of geodynamics due to its large impact on the physical and chemical properties of the Earth’s mantle, such as electrical conductivity, seismic anisotropy, diffusion, and rheology. In this study, we synthesized hydrous forsterite at 1100 C° and up to 4 GPa with either a piston-cylinder or multianvil apparatus. As a starting material, we used synthetic forsterite, unbuffered by SiO2, obtained by thermo‐mechanical activation of talc and magnesium carbonate hydroxide. Hydration was carried out using liquid H2O as hydrogen source. Samples were polycrystalline in an effort to distribute H2O throughout the sample both rapidly and homogeneously. Using the Paterson calibration, we observed total water content concentrations ranging between 100 and 500 ppm wt H2O. Multiple absorption bands are found in the frequency range between 3400 and 3650 cm−1, identifying at least seven peaks in all samples. Vibrational bands were centered at 3476, 3535, 3550, 3566, 3578, 3605, and 3612 cm−1, in good agreement with experimental studies conducted on both hydrous forsterite and single crystals of olivine. The stronger OH stretching peaks can be attributed to vibrational modes associated with the hydrogarnet defect 4HSix in which four protons occupy a vacant tetrahedral site. None of the OH bands observed are found at frequencies associated with hydrogen occupying vacant octahedral sites. High-temperature FTIR spectroscopy was used to evaluate the evolution of IR spectra as a function of temperature, up to 500 °C. The complete reversibility of peak absorption vs temperature in the OH stretching region confirms that no water loss occurred during heating. We observe an overall a decrease in total absorption with increasing temperature, and a prominent decrease in the relative intensities of the higher frequency bands (>3600 cm−1) with respect to lower frequency bands. We have assigned a series of equilibrium expressions based on the variation of relative peak areas with temperature and find that enthalpies of these processes range between 0.047–0.068 eV (4.5–6.5 kJ/mol), very low in comparison to activation energies observed for electrical conduction in hydrous olivine. Major changes in the vibrational spectrum are expected to be related to configurational changes of the same fully protonated hydrogarnet defect species. However, the complexity of the FTIR spectra may also be related to partially protonated defects, such as the associate defect 3HSi’ + Hi• generated by a dissociation reaction of the hydrogarnet species.

Abstract. Previous measurements of water in deformed quartzites using conventional Fourier transform infrared spectroscopy (FTIR) instruments have shown that water contents of larger grains vary from one grain to another. However, the non-equilibrium variations in water content between neighboring grains and within quartz grains cannot be interrogated further without greater measurement resolution, nor can water contents be measured in finely recrystallized grains without including absorption bands due to fluid inclusions, films, and secondary minerals at grain boundaries.Synchrotron infrared (IR) radiation coupled to a FTIR spectrometer has allowed us to distinguish and measure OH bands due to fluid inclusions, hydrogen point defects, and secondary hydrous mineral inclusions through an aperture of 10 µm for specimens > 40 µm thick. Doubly polished infrared (IR) plates can be prepared with thicknesses down to 4–8 µm, but measurement of small OH bands is currently limited by strong interference fringes for samples < 25 µm thick, precluding measurements of water within individual, finely recrystallized grains. By translating specimens under the 10 µm IR beam by steps of 10 to 50 µm, using a software-controlled x − y stage, spectra have been collected over specimen areas of nearly 4.5 mm2. This technique allowed us to separate and quantify broad OH bands due to fluid inclusions in quartz and OH bands due to micas and map their distributions in quartzites from the Moine Thrust (Scotland) and Main Central Thrust (Himalayas).Mylonitic quartzites deformed under greenschist facies conditions in the footwall to the Moine Thrust (MT) exhibit a large and variable 3400 cm−1 OH absorption band due to molecular water, and maps of water content corresponding to fluid inclusions show that inclusion densities correlate with deformation and recrystallization microstructures. Quartz grains of mylonitic orthogneisses and paragneisses deformed under amphibolite conditions in the hanging wall to the Main Central Thrust (MCT) exhibit smaller broad OH bands, and spectra are dominated by sharp bands at 3595 to 3379 cm−1 due to hydrogen point defects that appear to have uniform, equilibrium concentrations in the driest samples. The broad OH band at 3400 cm−1 in these rocks is much less common. The variable water concentrations of MT quartzites and lack of detectable water in highly sheared MCT mylonites challenge our understanding of quartz rheology. However, where water absorption bands can be detected and compared with deformation microstructures, OH concentration maps provide information on the histories of deformation and recovery, evidence for the introduction and loss of fluid inclusions, and water weakening processes.

We have established that increase in magnesium concentration in LiNbO3:Mg(0.19-5.91 mol% MgO) crystals leads to re-structuring in defective structure and optical anomalies connected with the re-structuring. The anomalies have threshold character. Optical uniformity of crystals was shown to increase at Mg concentration close to a threshold one ~3.0 mol% MgO. IR-absorption spectrum in the area of stretching vibrations of OH groups shifts to a high-frequency area (~50 cm-1 in comparison with other crystals), when Mg concentration nears the second threshold. At this sharp decrease in protons amount and jump-like shift of an absorption edge in the shortwave region are also observed. The shift was shown to be caused by the fact that at 5.5 mol% MgO all point defects NbLi are substitutes by Mg cations and with an increase in Mg concentration, Mg cations occupy Li and Nb sites forming point defects MgLi and MgNb.

Abstract. Single crystals of synthetic Cr-doped forsterite (Cr:Mg2SiO4) containing both Cr3+ and Cr4+ were partially hydroxylated in piston-cylinder apparatuses at 750–1300 ∘C and pressures from 0.5 to 2.5 GPa, with p(H2O) ≈Ptotal. The oxygen fugacity (fO2) was buffered by graphite-water, Ni–NiO, Re–ReO2, Fe2O3–Fe3O4 or Ag–Ag2O, and the silica activity (aSiO2) was buffered by powdered forsterite plus either enstatite (Mg2Si2O6), periclase (MgO) or zircon–baddeleyite (ZrSiO4–ZrO2). Profiles of OH content versus distance from the crystal edge were determined using Fourier transform infrared (FTIR) spectroscopy, and profiles of the oxidation state and coordination geometry of Cr were obtained, at the same positions, using K-edge X-ray absorption near-edge structure (XANES) spectroscopy. The techniques are complementary – FTIR spectroscopy images the concentration and nature of O–H bonds, where Cr K-edge XANES spectroscopy shows the effect of the added H on the speciation of Cr already present in the lattice. Profiles of defect-specific absorbance derived from FTIR spectra were fitted to solutions of Fick's second law to derive diffusion coefficients, which yield the Arrhenius relationship for H diffusion in forsterite: log⁡10D̃[001]=-2.5±0.6+-(224±12+4.0±2.0P)2.303RT, where D̃ is the measured diffusion coefficient in m2 s−1, valid for diffusion parallel to [001] and calibrated between 1000 and 750 ∘C, P and T are in GPa and K, and R is 0.008314 kJK−1 mol−1. Diffusivity parallel to [100] is around 1 order of magnitude lower. This is consistent with previous determinations of H diffusion associated with M-site vacancies. The FTIR spectra represent a variety of Cr-bearing hydrous defects, along with defects associated with the pure Mg–Si–O–H system. It is proposed that all of the defects can form by interaction between the dry lattice, including Cr3+ and Cr4+, and fully hydroxylated M-site vacancies. The initial diffusive wave of hydroxylation is associated with neither reduction nor oxidation of Cr but with Cr4+ changing from tetrahedral to octahedral coordination. Superimposed on the H diffusion and concomitant change in Cr4+ site occupancy, but at a slower rate, producing shorter profiles, is reduction of Cr4+ to Cr3+ and potentially of Cr4+ and Cr3+ to Cr2+. In addition, by comparing FTIR data to trace element contents measured by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), constraints can be placed on absorption coefficients used for converting absorbance to H2O contents – our data support either wavenumber- or defect-dependent values of absorption coefficients. We estimate absorption coefficients of between 60 200 and 68 200 L mol−1 cm−1 for OH− associated with octahedral Cr3+ and an M-site vacancy and 18 700 to 24 900 L mol−1 cm−1 for two OH− associated with octahedrally coordinated Cr4+ and a Si vacancy (i.e. a “clinohumite-type” point defect).

This article is focusing on electrical functionalization of biomaterial’s surface to enhance its biocompatibility. It is an overview of previously unpublished results from a series of experiments concerning the effects surface electrical functionalization can have on biological systems. Saccharomyces cerevisiae cells were used for biological experiments. The hydroxyapatite (HAp) specimens were used to investigate influence of structural point defects on the surface electrical charge. Threshold photoelectron emission spectroscopy was used to measure the electron work function of HAp and biologic samples. The density functional theory and its different approximations were used for the calculation of HAp structures with defects. It was shown that the electrical charge deposition on the semiconductor or dielectric substrate can be delivered because of production of the point defects in HAp structure. The spatial arrangements of various atoms of the HAp lattice, i.e., PO4 and OH groups, oxygen vacancies, interstitial H atoms, etc., give the instruments to deposit the electrical charge on the substrate. Immobilization of the microorganisms can be achieved on the even surface of the substrate, characterized with a couple of nanometer roughness. This cells attachment can be controlled because of the surface electrical functionalization (deposition of the electrical charge). A protein layer as a shield for the accumulated surface charge was considered, and it was shown that the protein layer having a thickness below 1 µm is not crucial to shield the electrical charge deposited on the substrate surface. Moreover, the influence of surface charge on the attachment of microorganisms, when the surface roughness is excluded, and the influence of controlled surface roughness on the attachment of microorganisms, when surface charge is constant, were also considered.

The natures of most radiation-induced point defects in amorphous silicon dioxide (a-SiO2) are well known on the basis of 56 years of electron spin resonance (ESR) and optical studies of pure and doped silica glass in bulk, thin-film, and fiber-optic forms. Many of the radiation-induced defects intrinsic to pure and B-, Al-, Ge-, and P-doped silicas are at least briefly described here and references are provided to allow the reader to learn still more about these, as well as some of those defects not mentioned. The metastable self-trapped holes (STHs), intrinsic to both doped and undoped silicas, are argued here to be responsible for most transient red/near-IR optical absorption bands induced in low-OH silica-based optical fibers by ionizing radiations at ambient temperatures. However, accelerated testing of a-SiO2-based optical devices slated for space applications must take into account the highly supralinear dependence on ionizing-dose-rate of the initial STH creation rate, which if not recognized would lead to false negatives. Fortunately, however, it is possible to permanently reduce the numbers of environmentally or operationally created STHs by long-term preirradiation at relatively low dose rates. Finally, emphasis is placed on the importance and utility of rigorously derived fractal-kinetic formalisms that facilitate reliable extrapolation of radiation-induced optical attenuations in silica-based photonics recorded as functions of dose rate backward into time domains unreachable in practical laboratory times and forward into dose-rate regimes for which there are no present-day laboratory sources.

Abstract. The build-up of intrinsic Bjerrum and ionic defects at ice-vapor interfaces electrically charges ice surfaces and thus gives rise to many phenomena including thermoelectricity, ferroelectric ice films, sparks from objects in blizzards, electromagnetic emissions accompanying cracking in avalanches, glaciers, and sea ice, and charge transfer during ice-ice collisions in thunderstorms. Fletcher's theory of the ice surface in equilibrium proposed that the Bjerrum defects have a higher rate of creation at the surface than in the bulk, which produces a high concentration of surface D defects that then attract a high concentration of OH- ions at the surface. Here, we add to this theory the effect of a moving interface caused by growth or sublimation. This effect can increase the amount of ionic surface charges more than 10-fold for growth rates near 1 mm s-1 and can extend the spatial separation of interior charges in qualitative agreement with many observations. In addition, ice-ice collisions should generate sufficient pressure to melt ice at the contact region and we argue that the ice particle with the initially sharper point at contact loses more mass of melt than the other particle. A simple analytic model of this process with parameters that are consistent with observations leads to predicted collisional charge exchange that semiquantitatively explains the negative charging region of thunderstorms. The model also has implications for snowflake formation, ferroelectric ice, polarization of ice in snowpacks, and chemical reactions in ice surfaces

AbstractObjectivesCongenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21-OHD) is a common autosomal recessive disorder caused by defects in the CYP21A2 gene. We aimed to determine the prevalence of the most commonly reported mutations among 21-OHD Egyptian patients and correlate genotype with phenotype.MethodsMolecular analysis of the CYP21A2 gene was performed for the detection of the six most common point mutations (p.P30L, p.I172N, p.V281L, p.Q318X, the splice site mutation Int2 [IVS2–13A/C>G], and the cluster of three mutations [p.I236N, p.V237E, and p.M239K] designed as CL6). Polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) method was performed on 47 unrelated Egyptian 21α-OH deficiency patients and their available parents to detect the presence of the six most common point mutations.ResultsScreening for the six most common point mutations in CYP21A2 gene, revealed mutations in 87.2% (82/94) of the studied alleles corresponding to 47 Egyptian patients. The most common mutation among the studied cases was IVS2-13C/A>G that was found to be presented in a frequency of 46.8% (44/94). The genotype/phenotype correlations related to null, A, and B groups were with PPV of 100, 55.5, and 83.3%, respectively.ConclusionsThe described method diagnosed CAH in 80.8% of the studied patients. Good correlation between genotype and phenotype in salt wasting and simple virilizing forms is determined, whereas little concordance is seen in nonclassical one. Furthermore, studying the carrier frequency of 21-OHD among the normal population is of great importance.

The crystallisation of sputter-deposited, amorphous In2O3:H films was investigated. The influence of deposition and crystallisation parameters onto crystallinity and electron hall mobility was explored. Significant precipitation of metallic indium was discovered in the crystallised films by electron energy loss spectroscopy. Melting of metallic indium at ~160 °C was suggested to promote primary crystallisation of the amorphous In2O3:H films. The presence of hydroxyl was ascribed to be responsible for the recrystallization and grain growth accompanying the inter-grain In-O-In bounding. Metallic indium was suggested to provide an excess of free electrons in as-deposited In2O3 and In2O3:H films. According to the ultraviolet photoelectron spectroscopy, the work function of In2O3:H increased during crystallisation from 4 eV to 4.4 eV, which corresponds to the oxidation process. Furthermore, transparency simultaneously increased in the infraredspectral region. Water was queried to oxidise metallic indium in UHV at higher temperature as compared to oxygen in ambient air. Secondary ion mass-spectroscopy results revealed that the former process takes place mostly within the top ~50 nm. The optical band gap of In2O3:H increased by about 0.2 eV during annealing, indicating a doping effect. This was considered as a likely intra-grain phenomenon caused by both (In0)O•• and (OH−)O• point defects. The inconsistencies in understanding of In2O3:H crystallisation, which existed in the literature so far, were considered and explained by the multiplicity and disequilibrium of the processes running simultaneously.

Abstract Mutations in daf-2 and age-1 cause a dramatic increase in longevity as well as developmental arrest at the dauer diapause stage in Caenorhabditis elegans. daf-2 and age-1 encode components of an insulin-like signaling pathway. Both daf-2 and age-1 act at a similar point in the genetic epistasis pathway for dauer arrest and longevity and regulate the activity of the daf-16 gene. Mutations in daf-16 cause a dauer-defective phenotype and are epistatic to the diapause arrest and life span extension phenotypes of daf-2 and age-1 mutants. Here we show that mutations in this pathway also affect fertility and embryonic development. Weak daf-2 alleles, and maternally rescued age-1 alleles that cause life span extension but do not arrest at the dauer stage, also reduce fertility and viability. We find that age-1(hx546) has reduced both maternal and zygotic age-1 activity. daf-16 mutations suppress all of the daf-2 and age-1 phenotypes, including dauer arrest, life span extension, reduced fertility, and viability defects. These data show that insulin signaling, mediated by DAF-2 through the AGE-1 phosphatidylinositol-3-OH kinase, regulates reproduction and embryonic development, as well as dauer diapause and life span, and that DAF-16 transduces these signals. The regulation of fertility, life span, and metabolism by an insulin-like signaling pathway is similar to the endocrine regulation of metabolism and fertility by mammalian insulin signaling.

This paper describes the design of a new magnetic flux leakage (MFL) inspection tool that performs an inline inspection to detect and characterize both metal loss and mechanical damage defects. An inspection tool that couples mechanical damage assessment as part of a routine corrosion inspection is expected to have considerably better prospects for application in the pipeline industry than a tool that complicates existing procedures. The design is based on study results that show it is feasible to detect and assess mechanical damage by applying a low magnetic field level in addition to the high magnetic field employed by most inspection tools. Nearly all commercially available MFL tools use high magnetic fields to detect and size metal loss such as corrosion. A lower field than is commonly applied for detecting metal loss is appropriate for detecting mechanical damage, such as the metallurgical changes caused by impacts from excavation equipment. The lower field is needed to counter the saturation effect of the high magnetic field, which masks and diminishes important components of the signal associated with mechanical damage. Finite element modeling was used in the design effort and the results have shown that a single magnetizer with three poles is the most effective design. Furthermore, it was found that for the three-pole system the high magnetization pole must be in the center, which was an unexpected result. The three-pole design has mechanical advantages, including a magnetic null in the backing bar, which enables installation of a pivot point for articulation of the tool through bends and restrictions. This design was prototyped and tested at Battelle’s Pipeline Simulation Facility (West Jefferson, OH). The signals were nearly identical to results acquired with a single magnetizer reconfigured between tests to attain the appropriate high and low field levels.

For the key-optical material, the laser induced damage character of fused silica is crucial for the application among the optical laser fitting. As the defect of each point of the silica sample is diverse, and the lasers focus point by point, we divided the sample block into three-dimensional structure for each laser-point to discuss the relationship between the LIDT of each points and the OH-content. The result shows that the LIDT of the center of the sample block is up to 10-11J/cm2 which is consistent after the treatment while the LIDT of border pieces is 9-10 J/cm2. The different temperature and the aggradation during the fusing process and the machine process caused the different OH content of different location of the sample.

Improvement of channel mobility is required to improve the performance of the inversion channel MOSFETs using diamond. The previous studies have suggested that high interface defect density (Dit) at the Al2O3/diamond (111) interface has a significant impact on the carrier transport property on a channel region. To investigate the physical origins of the high Dit, especially from microscopic point of view, here we investigate Al2O3/p-type diamond (111) interfaces using scanning nonlinear dielectric microscopy (SNDM). We find the high spatial fluctuations of Al2O3/hydroxyl (OH)-terminated diamond (111) interface properties and their difference by the flatness of the diamond surface.

AbstractA detailed understanding of the response of mineral phases to the radiation fields experienced in a geological disposal facility (GDF) is currently poorly constrained. Prolongued ion irradiation has the potential to affect both the physical integrity and oxidation state of materials and therefore may alter a structure's ability to react with radionuclides. Radiohalos (spheres of radiation damage in minerals surrounding radioactive (α-emitting) inclusions) provide useful analogues for studying long term α-particle damage accumulation. In this study, silicate minerals adjacent to Th- and U-rich monazite and zircon were probed for redox changes and long/short range disorder using microfocus X-ray absorption spectroscopy (XAS) and high resolution X-ray diffraction (XRD) at Beamline I18, Diamond Light Source. Fe3+ → Fe2+ reduction has been demonstrated in an amphibole sample containing structural OH– groups – a trend not observed in anhydrous phases such as garnet. Coincident with the findings of Pattrick et al. (2013), the radiolytic breakdown of OH– groups is postulated to liberate Fe3+ reducing electrons. Across all samples, high point defect densities and minor lattice aberrations are apparent adjacent to the radioactive inclusion, demonstrated by micro-XRD.

In situ measurements of sensing signals in space platforms requires that the micro-electro-mechanical system (MEMS) sensors be located directly at the point to be measured and in contact with the subject to be measured. Traditional radiation-tolerant silicon-based MEMS sensors cannot acquire spatial signals directly. Compared to silicon-based structures, LiNbO3 single crystalline has wide application prospects in the aerospace field owing to its excellent corrosion resistance, low-temperature resistance and radiation resistance. In our work, 4-inch LiNbO3 and LiNbO3/Cr/Au wafers are fabricated to silicon substrate by means of a polyimide bonding method, respectively. The low-temperature bonding process (≤100 ℃) is also useful for heterostructure to avoid wafer fragmentation results from a coefficient of thermal expansion (CTE) mismatch. The hydrophilic polyimide surfaces result from the increasing of -OH groups were acquired based on contact angle and X-ray photoelectron spectroscopy characterizations. A tight and defect-free bonding interface was confirmed by scanning electron microscopy. More importantly, benefiting from low-temperature tolerance and radiation-hardened properties of polyimide material, the bonding strength of the heterostructure based on oxygen plasma activation achieved 6.582 MPa and 3.339 MPa corresponding to room temperature and ultra-low temperature (≈ -263.15 °C), which meets the bonding strength requirements of aerospace applications.

In situ measurements of sensing signals in space platforms requires that the micro-electro-mechanical system (MEMS) sensors be located directly at the point to be measured and in contact with the subject to be measured. Traditional radiation-tolerant silicon-based MEMS sensors cannot acquire spatial signals directly. Compared to silicon-based structures, LiNbO3 single crystalline has wide application prospects in the aerospace field owing to its excellent corrosion resistance, low-temperature resistance and radiation resistance. In our work, 4-inch LiNbO3 and LiNbO3/Cr/Au wafers are fabricated to silicon substrate by means of a polyimide bonding method, respectively. The low-temperature bonding process (≤100 °C) is also useful for heterostructure to avoid wafer fragmentation results from a coefficient of thermal expansion (CTE) mismatch. The hydrophilic polyimide surfaces result from the increasing of -OH groups were acquired based on contact angle and X-ray photoelectron spectroscopy characterizations. A tight and defect-free bonding interface was confirmed by scanning electron microscopy. More importantly, benefiting from low-temperature tolerance and radiation-hardened properties of polyimide material, the bonding strength of the heterostructure based on oxygen plasma activation achieved 6.582 MPa and 3.339 MPa corresponding to room temperature and ultra-low temperature (≈ −263.15 °C), which meets the bonding strength requirements of aerospace applications.

Abstract Most residents in developing countries suffer severe water shortage and often resort to self-supply. Unfortunately, some self-supply water sources contain disease-causing biological and chemical contaminants and require point-of-use (POU) treatment. However, recontamination and persistence of chemical contaminants occur, which defeats the aim of POU. This study aims to develop an affordable low-technology system that effectively treats whole-house water sourced from borehole and rain without recontamination. Raw borehole water (RBW) was treated with KAl(SO4)2·12H2O (8.10 mg/L), Ca(OH)2 (68.21 mg/L) and NaOCl (1.875 mg/L) in two separate tanks and thereafter filtered through 5-micron and 0.5-micron carbon filters, and a reverse osmosis system. The results showed that heterotrophic plate count (2,700 CFU/mL) and total coliform (378.00±21.25 MPN/100 mL) in RBW were reduced to zero, and total hardness was reduced by &gt;83% after treatment and there was no recontamination. Chromium (0.05±0.002 mg/L), Cu (0.04±0.001 mg/L), Pb (0.09±0.001 mg/L), Fe (0.26±0.005 mg/L) and Mn (0.2±0.001 mg/L) in the RBW were reduced below detectable limits after treatment. The annual per capita cost of water treatment was estimated at N 4,744.44 ($9.32) at per capita consumption of 100 L/day. Our technology shows exceptional promise in providing affordable and safe water to the entire household throughout the year.

This article briefly reviews some of our recent work carried out both from an experimental point of view as well as from a theoretical perspective to gain further understanding of the events that take place in Heterogeneous Photocatalysis. Previously, the multitude of reports from our laboratory and from many others looked at the primary photocatalytic events as involving (a) absorption of light, (b) formation of the free (electrons and holes) and/or trapped charge carriers (Ti3+and •OH radicals), and (c) reaction of pre-adsorbed acceptor or donor molecules with the relevant trapped carrier. Our recent work notes that this view is reasonable if the only purpose of photocatalysis is elimination of undesirable environmental pollutants. But when we begin to query how to render a process more efficient, we need to address the primary events following photoexcitation of the photocatalyst, which in most instances has been titanium dioxide (in the anatase form). Owing to the nature of light absorption byTiO2we resorted to examining other metal oxides, most of which are dielectric insulators with very large bandgap energies, for example zirconia (ZrO2) and scandia (Sc2O3). These dielectrics have provided added information on the photophysical events, many of which are masked by the strong light absorption in titania. Despite some of our recent progress, much remains to be done for a fuller understanding of the events that occur at the surface, which we have often considered to be the greatest and most complex defect in metal oxide particulates.

Introduction Such symptoms as hard, complex, bodily or mental feelings, that turn our everyday life into a hell, at first, lead us to a doctor, and then - to a psychotherapist. A sick man is keen to get rid of a symptom. A doctor prescribes medication, that is ought to eliminate a symptom. A psychotherapist searches for a reason of the problem that needs to be removed. There is such an idea that a neurotic symptom, in particular, an anxiety - is a pathological (spare or extra) response of a body. It is generally believed that such anxiety doesn’t have some real, objective reasons and that it is the result of a nervous system disorder, or some disruption of a cognitive sphere etc. Meanwhile, it is known that in the majority of cases, medical examinations of anxious people show that they don’t have any organic damages, including nervous system. It often happens that patients even wish doctors have found at least any pathology and have begun its treatment. And yet - there is no pathology. All examinations indicate a high level of functionality of a body and great performance of the brain's work. Doctors throw their hands up, as they can't cure healthy people. One of my clients told me her story of such medical examinations (which I’ll tell you with her permission). She said that it was more than 10 years ago. So, when she told her doctor all of her symptoms - he seemed very interested in it. He placed a helmet with electrodes on her head and wore some special glasses, when, according to her words, he created some kind of stressful situation for her brain, as she was seeing some flashings of bright pictures in her eyes. She said that he had been bothered with her for quite a long time, and at the end of it he had told her that her brain had been performing the best results in all respects. He noted that he’d rarely got patients with such great health indicators. My client asked the doctor how rare that was. And he answered: “one client in two or three months.” At that moment my client didn’t know whether to be relieved, flattered or sad. But since then, when someone told her that anxiety was a certain sign of mental problems, or problems with the nervous system, or with a body in general, she answered that people who had anxiety usually had already got all the required medical examinations sufficiently, and gave them the advice to go through medical screening by themselves before saying something like that. Therefore, we see a paradoxical situation, when some experts point to a neurotic anxiety as if it is a kind of pathology, in other words - some result of a nervous system disorder. Other specialists in the same situation talk about cognitive impairments. And some, after all the examinations, are ready to send such patients into space Main text I don’t agree with the statement that any neurotic anxiety that happens is excessive and unfounded. It often happens that there is objective, specific and real causes for appearance of anxiety conditions. And these causes require solutions. And it’s not about some organic damages of the brain or nervous system. The precondition that may give a rise to anxiety disorder is the development of such a life story that at some stage becomes too toxic - when, on the one hand, a person interacts with the outside world in a way that destroys his or her personality, and, on the other hand, this person uses repression and accepts such situation as common and normal. Repression - is an essential condition for the development of a neurotic symptom. Sigmund Freud was the first who pointed this out. Repression is such a defense mechanism that helps people separate themselves from some unpleasant feelings of discomfort (pain) while having (external or internal) irritations. It is the situation when, despite the presence of irritations and painful feelings, a person, however, doesn't feel any of it and is not aware of them in his or her conscious mind. Repression creates the situation of so-called emotional anesthesia. As a result, a displacement takes place, so a body starts to signal about the existing toxic life situation via a symptom. Anxiety disorder is usually an appropriate response (symptom) of a healthy body to an unhealthy life situation, which is seen by a person as normal. And it’s common when such a person is surrounded by others (close people), who tend to benefit from such situation, and so they actively maintain this state of affairs, whether it is conscious for them or not. At the beginning of a psychotherapy almost all clients insist that everything is good in their lives, even great, as it is like in everyone else’s life. They say that they have only one problem, which is that goddamn symptom. So they focus all of their attention on that symptom. They are not interested in all the other aspects of their life, and they show their irritation when it comes to talking about it. People want to get rid of it, whatever it takes, but they often tend to keep their lives the way that it was. In such cases a psychotherapist is dealing with the resistance of clients, trying to turn their attention from a symptom to their everyday situation that includes their way of thinking, interactions with themselves and with others and with the external world in order to have the opportunity to see the real problem, to live it through, to rethink and to change the story of their lives. For better understanding about how it works I want to tell you three allegorical tales. The name of the first tale is “A frog in boiling water”. There is one scientific anecdote and an assumption (however, it is noted that such experiments were held in 19 century), that if we put a frog in a pot with warm water and start to slowly heat the water, then this frog get used to the temperature rise and stays in a hot water, the frog doesn’t fight the situation, slowly begins to lose its energy and at the last moment it couldn’t find enough strength and energy to get out of that pot. But if we throw a frog abruptly in hot water - it jumps out very quickly. It is likely that a frog, that is seating in boiling water, will have some responses of the body (symptoms). For example, the temperature of its body will rise, the same as the color of it, etc., that is an absolutely normal body response to the existing situation. But let us keep fantasizing further. Imagine a cartoon where such a frog is the magical cartoon hero, that comes to some magical cartoon doctor, shows its skin, that has changed the color, to the doctor, and asks to change the situation by removing this unpleasant symptom. So the doctor prescribes some medication to return the natural green color of the frog’s skin back. The frog gets back in its hot water. For some period of time this medication helps. But then, after a while, the frog’s body gets over the situation, and the redness of the frog's skin gets back. And the magical cartoon doctor states that the resistance of the body to this medication has increased, and each time prescribes some more and more strong drugs. In this example with the frog it is perfectly clear that the true solution of the problem requires the reduction of the water temperature in that pot. We could propose that magical cartoon frog to think and try to realize that: 1) the water in that pot is hot, and that is the reason why the skin is red; 2) the frog got used to this situation and that is why it is so unnoticeably for this frog; 3) if the temperature of the water in the pot still stay so hot, without any temperature drop, then all the medication works only temporarily; 4) if we lower the temperature in that pot - the redness disappears on its own, automatically and without any medication. Also this cartoon frog, that will go after the doctor to some cartoon physiotherapist, will face the necessity to give itself some answers for such questions as: 1) What is going on? Who has put this frog in that pot? Who is raising the temperature progressively? Who needs it? And what is the purpose or benefit for this person in that? Who benefits? 2) Why did the frog get into the pot? What are the benefits in it for the frog? Or why did the frog agree to that? 3) What does the frog lose when it gets out of this pot? What are the consequences of it for the frog? What does the frog have to face? What are the possible difficulties on the way? Who would be against the changes? With whom the frog may confront? 4) Is the frog ready to take control over its own pot in its own hands and start to regulate the temperature of the water by itself, so to make this temperature comfortable for itself? Is this frog ready to influence by itself on its own living space, to take the responsibility for it to itself? The example “A frog in boiling water” is often used as a metaphorical portrayal of the inability of people to respond (or fight back) to significant changes that slowly happen in their lives. Also this tale shows that a body, while trying to adjust to unfavorable living conditions, will react with a symptom. And it is very important to understand this symptom. Symptom - is the response of a body, it’s a way a body adjusts to some unfriendly environment. Symptom, on the one hand, informs about the existence of a problem, and from the other hand - tries to regulate this problem, at least in some way (like, to remove or reduce), at the level on which it can do it. The process is similar to those when, for example, in a body, while it suffers from some infectious disease, the temperature rises. Thus, on the one hand, the temperature informs about the existence of some infection. On the other hand, the temperature increase creates in a body the situation that is damaging for the infection. So, it would be good to think about in what way does an anxiety symptom help a body that is surrounded by some toxic life situation. And this is a good topic for another article. Here I want to emphasize that all the attempts to remove a symptom without a removal of a problem, without changing the everyday life story, may lead to strengthening of the symptom in the body. Even though the removal of a symptom without elimination of its cause has shown success, it only means that the situation was changed into the condition of asymptomatic existence of a problem. And it is, in its essence, a worse situation. For example, it can cause an occurrence of cancer. The tale “A frog in boiling water” is about the tendency of people to treat a symptom, instead of seeing their real problems, as its cause, and trying to solve it. People don’t want to see their problems, but it doesn’t mean that the problem doesn’t exist. The problem does exist and it continues to destroy a person, unnoticeably for him or her. A person with panic disorder could show us anxiety that is out of control (fear, panic), which, by its essence, seems to exist without any logical reason. Meanwhile the body of such a person could be in such processes that are similar to those that occur in the conditions of some real dangers, when the instinct for self-preservation is triggered and an automatic response of a body to fight or flight implements for its full potential. We can see or feel signs of this response, for example, in cases when some person tries to avoid some real or imaginary danger via attempts to escape (the feeling of fear), or tries to handle the situation by some attempts to fight (the feeling of anger). As I mentioned before, many doctors believe that such fear is pathological, as there is no real reason for such intense anxiety. They may see the cause of the problem in worrisome temper, so they try to remove specifically anxiety rather than help such patients to understand specific reason of their anxiety, they use special psychotherapeutic methods that are designed to help clients to develop logical thinking, so it must help them to realize the groundlessness of their anxiety. In my point of view, such anxiety often has specific, real reasons, when this response of a body, fight or flight, is absolutely appropriate, but not excessive or pathological. Inadequacy, in fact, is in the unconsciousness, but not in the reactions of a body. For a better understanding of the role of anxiety in some toxic environment, that isn’t realized, I want to tell you another allegorical tale called “The wolf and the hare”. Let us imagine that two cages were brought together in one room. The wolf was inside one cage and the hare was in another. The cages were divided by some kind of curtain that makes it impossible for them to see each other. At this point a question arises whether the animals react to each other in some way in such a situation, or not? I think that yes, they will. Since there are a lot of other receptors that participate in the receiving and processing of the sensory information. As well as sight and hearing, we have of course a range of other senses. For example, animals have a strong sense of smell. It is well known that people, along with verbal methods of communicating information, like language and speaking, also have other means of transmitting information - non-verbal, such as tone of voice, intonation, look, gestures, body language, facial expressions etc., that gives us the opportunity to receive additional information from each other. The lie detector works by using this principle: due to detecting non-verbal signals, it distinguishes the level of the accuracy of information that is transmitted. It is assumed, that about 30% of information, that we receive from the environment, comes through words, vision, hearing, touches etc. This is the information that we are aware of in our consciousness, so we could consciously (logically) use it to be guided by. And approximately 70% of everyday information about the reality around us we receive non-verbally, and this information in the majority of cases could remain in us without any recognition. It is the situation when we’ve already known something, and we even have already started to respond to it via our body, but we still don’t know logically and consciously that we know it. We can observe the responses of our own body without understanding what are the reasons for such responses. We can recognize this unconscious information through certain pictures, associations, dreams, or with the help of psychoanalysis. Psychoanalysis is a great tool that can help to recognize the information from the unconscious mind, so that it can be logically processed further on, in other words, a person then receives the opportunity to indicate the real problems and to make right decisions. But let us return to the tale where the hare and the wolf stay in one room and don’t see each other, and, maybe, don’t hear, though - feel. These feelings (in other words - non-verbal information that the hare receives) activate a certain response in the hare’s body. And it reacts properly and adequately to the situation, for instance, the body starts to produce adrenaline and runs the response “fight or flight”. So the hare starts to behave accordingly and we could see the following symptoms: the hare is running around his cage, fussing, having some tremor and an increased heart rate, etc.. And now let us imagine this tale in some cartoon. The hare stays in its house, and the wolf wanders about this house. But the hare doesn’t see the wolf. Though the body of the hare gives some appropriate responses. And then that cartoon hare goes to a cartoon doctor and asks that doctor to give it some pill from its tremor and the increased heart rate. And in general asks to treat in some way this incomprehensible, confusing, totally unreasonable severe anxiety. If we try to replace the situation from this fairy-tale to a life story, we could see that it fits well to the script of interdependent relationships, where there are a couple “a victim and an aggressor”, and where such common for our traditional families’ occurrences as a domestic family violence, psychological and physical abuse take place. Only in 2019 a law was passed that follows the European norms and gives a legislative definition of such concepts as psychological domestic abuse, sexual abuse, physical abuse, bullying, that criminalizes all of these occurrences, establishes the punishment and directly points to people that could be a potential abuser. Among them are: a husband towards his wife, parents towards their children, a wife towards her husband, a superior towards a subordinate, a teacher towards his or her students, children towards each other etc.. When it comes to recognition of something as unacceptable, it seems more easy to put to that category such occurrences as physical and sexual abuse, as we could see here some obvious events. For example, beating or sexual harassment. Our society is ready to respond to these incidents in more or less adequate way, and to recognize them as a crime. But it is harder to deal with the recognition of psychological abuse as an offence. Psychological abuse in our families is common. Psychological abuse occurs through such situations, when one person, while using different psychological manipulations, such as violation of psychological borders, imposition of feeling of guilty or shame, etc., force another person to give up his or her needs and desires, and so in such a way make this person live another’s life. Such actions have an extremely negative effect on the mental health of these people, just as much as physical abuse. It can destroy a person from the inside, ruin self-esteem and a feeling of self-worth, create the situation of absolute dependence such victim from an abuser, including financial dependence etc.. It often happens that psychological abuse takes place against the backdrop of demonstrations of care and love. So you've got this story about the wolf and the hare, that are right next to each other, and the shield between two of them is a repression - a psychological defense mechanism, when a person turns a blind eye to such offences, that take place in his or her own life and towards him or her. And this person considers this as normal, doesn't realize, doesn't have a resource to realize, that it is a crime. Most importantly - doesn’t feel anything, as a repression takes place. But a body responds in a right way - from a certain point of the existence of such a toxic situation the response “fight or flight” is launched in a body at full, in other words - the fear and anxiety with the associated symptoms. The third allegorical tale I called “Defective suit”, which I read in the book of Clarissa Pinkola Estés with the name “Running With the Wolves". “Once one man came to a tailor and started to try on a suit. When he was standing in front of a mirror, he saw that the costume had uneven edges. - Don’t worry, - said the tailor. - If you hold the short edge of the suit by your left hand - nobody notices it. But then the man saw that a lapel of a jacket folded up a little bit. - It's nothing. You only need to turn your head and to nail it by your chin. The customer obeyed, but when he put on trousers, he saw that they were pulling. - All right, so just hold your trousers like this by your right hand - and everything will be fine, - the tailor comforts him. The client agreed with him and took the suit. The next day he put on his new suit and went for a walk, while doing everything exactly in the way that the tailor told him to. He waddled in a park, while holding the lapel by his chin, and holding the short edge of the suit by his left hand, and holding his trousers by his right hand. Two old men, who were playing checkers, left the game and started to watch him. - Oh, God! - said one of them. - Look at that poor cripple. - Oh, yes - the limp - is a disaster. But I'm wondering, where did he get such a nice suit?” Clarissa wrote: “The commentary of the second old man reflects the common response of the society to a woman, who built a great reputation for herself, but turned into a cripple, while trying to save it. “Yes, she is a cripple, but look how great her life is and how lovely she looks.” When the “skin” that we put on ourselves towards society is small, we become cripples, but try to hide it. While fading away, we try to waddle perky, so everyone could see that we are doing really well, everything is great, everything is fine”. As for me, this tale is also about the process of forming a symptom in a situation when one person tries very hard to match to another one, whether it is a husband, a wife or parents. It’s about a situation when such a person always tries to support the other one, while giving up his or her own needs and causing oneself harm in such a way by feeling a tension every day, that becomes an inner normality. And so this person doesn’t give oneself a possibility to relax, to be herself (or himself), to be spontaneous, free. As a result, in this situation the person, who was supported, looks perfect from the outside, but those who tried to match, arises some visible defect, like a limp - a symptom. And so this person lives like a cripple, under everyday stress and tension, trying to handle it, while sacrificing herself (or himself) and trying to maintain this situation, so not to lose the general picture of a beautiful family and to avoid shame. The tailor, who made this defective suit and tells how to wear the suit properly, in order to keep things going as they are going, often is a mother who raised a problematic child and then tells another person how to deal with her child in the right way. It is the situation when a mother-in-law tells her daughter-in-law how to treat her son properly. In other words, how to support him, when to keep silent, to handle, how to fit in, so that her problematic son and this relationship in general looks perfect. Or vice versa, when a mother-in-law tells her son-in-law how to support her problematic daughter, how to fit in etc.. When, for example, a woman acts like this in her marriage and with her husband, with these excessive efforts to fit in - then after a while everybody will talk like: “Look at this lovely man: he lives with his sick wife, and their family seems perfect!”. But when such a woman becomes brave enough to relax and to just let the whole thing go, everybody will see that the relationship in her marriage isn’t perfect, and it is the other one who has problems. Each time when someone tries excessively to match up to another one, while turning oneself in some kind of a cripple, - he or she, on the one hand, supports the comfort of that person, to whom he or she tries to match up, and on the other hand - such a situation always arises in that person such conditions as a continuous tension, anxiety, fear to act spontaneously. A symptom - is like a visible defect, that shows itself through the body (and may look like some kind of injury). It is the result of a hidden inner prison. As a result of evolution, a pain tells us about a problem that is needed to be solved. When we repress our pain we can’t see our needs and our problems at full. And then a body starts to talk to us via a symptom. Psychotherapy aims for providing a movement from a symptom to a resumption of sensitivity to feelings, a resumption of the ability to feel your psychological pain, so you can realize your own toxic story. In this perspective another fairy-tale looks interesting to analyze - it is Andersen's fairytale “Princess and the Pea”. In the tale a prince wanted to find a princess to marry. There was one requirement for women candidates, so the prince could select her among commoner - high level of sensitivity, as the real princess would feel a pea through the mountain of mattresses, and so she could have the ability to feel discomfort, to be in a good contact with her body, to tell about her discomfort without such feeling as shame and guilt, and to refuse that discomfort, so to have the readiness to solve her problems and to demand from others the respect for her needs. It is common for our culture that the expression “a princess on a pea” very often uses for a negative meaning. So people who are in good contact with their body and who can demand comfort for themselves are often called capricious. At the same time the heroes who are ready to suffer and to tolerate their pain, who are able to repress (stop to feel) their pain represents a good example to be followed in our society. So, we may see the next algorithm in cases of various anxiety disorders: the existence of some toxic situation that brings some danger to a person. And we need not to be confused: a danger exists not for a body, but for a personality. A toxic live situation as well as having a panic attack is not a threat for the health of a body (that is what medical examinations show), and vice versa - it’s like every day intensive sport training, that could be good for your health only to some degree. A toxic situation destroys a person as a personality, who longs for one self’s expression; the existence of such a defense mechanism as repression - it’s a life with closed eyes, in pink glasses, when there is inability (or the absence of the desire) to see its own toxic story; 3.the presence of a symptom - a healthy response of a body “fight or flight” to some toxic situation; displacement - it’s replacement of the attention from the situation to a symptom, when a person starts to see and search for the problem in some other place, not where it really is. A symptom takes as some spare, pathological reaction that we need to get rid of. The readiness to fight the symptom arises, and that is the goal of such methods of therapy as pharmacological therapy, CBT and many others; the absence of adequate actions that are directed towards the change of a toxic situation itself. The absence of the readiness to show aggression when it comes to protect its space. All of it is a mechanism of formation of primary anxiety and preparation for launch of secondary anxiety. A complete anxiety disorder is the interaction between a primary and a secondary anxiety.

AbstractWe have investigated the defect structure and protonic transport properties of nonstoichiometric complex perovskite-type compounds of the type A3B'1+xNb2-xO9-δ. where A and B' are both divalent ions. Protons are incorporated by treatment in H2O vapor and their presence is manifested by the appearance of an OH band in the IR spectra, as well as by the large increase in electrical conductivity to produce excellent protonic conductors, with lower activation energies. A non-classical isotope effect, in which the Arrhenius plots for D+ and H+ cross over, can be explained by a modification of the classical ART hopping theory.

ABSTRACTX-ray induced optical absorption has been studied on silica glasses densified by hot isostatic pressing. Density of the glass increases up to about 1% in proportion to the operating pressure. Two main absorption bands centered at 5.8eV(215nm) and 4.8eV(260nm) are induced both in the densified and undensified glasses under the irradiation of X-rays at room temperature. The 5.8eV band is enhanced with the increase in density for the glass with low-OH content(<˜200ppm), but is decreased slightly for the glass with high-OH content(>˜200ppm). On the other hand, the 4.8eV band decreases with the increase in density irrespective of OH content, and reaches at a constant value above the densification of about 0.5%. It is found that these absorption bands originate in point defects in the glass and that the densification improves the optical durability of the glass against X-rays when hydroxyl impurities are contained in the glass.

Purpose The purpose of this paper is to study the variations of composition and properties of the passive film on 316 L stainless steel surface in 80°C, 0.5 mol L-1 H2SO4 + 2 mg L-1 NaF solution, is helpful to understand the mechanisms of corrosion resistancethe of plated Pd on 316 L ss. Design/methodology/approach The variations of composition and properties of the passive film on 316 L stainless steel surface in 80°C, 0.5 mol L-1 H2SO4 + 2 mg L-1 NaF solution after connected to Pd electrode were studied with methods of potential monitor, X-ray photoelectron spectroscopy analysis and electrochemical impedance spectrum (EIS) measurement. Findings By connecting to a Pd electrode, the potential of the SS sample increased from the active region to the passive region. By connecting to the Pd electrode, the contents of Cr, Cr(OH)3 and Fe3O4 in passive film increased obviously. With increased Pd/SS area ratio, the Cr(OH)3 content in passive film increased but the Fe3O4 content changed little. The results show that after connecting to Pd the corrosion resistance of the passive film on 316 L stainless steel increases obviously, which may be attributed to the more compact passive film because of higher Cr, Cr(OH)3 and Fe3O4 contents and less point defects in the film. Originality/value The effects and mechanism of Pd on passivation of SS was studied.

ABSTRACTThe polishing technology used for manufacturing ultraflat and smooth Si surfaces on a large scale is the chemomechanical polishing (CMP) technique. This technique combines the chemical corrosive removal of silicon atoms and the mechanical transport of the agents. The removal rates strongly depend on the interaction of mechanical parameters and the chemistry involved in the polishing process like the pH of the alkaline polishing slurry used. Removal of Si during CMP is explained by a nucleophilic attack of OH− to silicon atoms catalyzing the corrosive reaction of H2O resulting in cleavage of silicon backbonds. Characterization of the surface chemistry of the silicon wafer after polishing by X-Ray Photoelectron Spectroscopy and High-Resolution Electron Energy Loss Spectroscopy reveals an oxide free, predominantly hydride covered silicon surface displaying hydrophobic properties. Morphological features like microroughness as well as localized surface irregularities on the silicon surface, also referred to as Light Point Defects, depend on different strongly interacting process parameters. Microroughness is reduced by CMP by several orders of magnitude as characterized by lightscattering techniques and Atomic Force Microscopy.

Summary A 33-year-old gentleman of Egyptian heritage presented with a 21 years history of unexplained and recurrent hypercalcaemia, nephrolithiasis, nephrocalcinosis, and myocarditis. A similar history was also found in two first-degree relatives. Further investigation into the vitamin D metabolism pathway identified the biochemical hallmarks of infantile hypercalcaemia type 1 (IIH). A homozygous, likely pathogenic, variant in CYP24A1 was found on molecular genetic analysis confirming the diagnosis. Management now focuses on removing excess vitamin D from the metabolic pathway as well as reducing calcium intake to achieve serum-adjusted calcium to the middle of the reference range. If undiagnosed, IIH can cause serious renal complications and metabolic bone disease. Learning points Infantile hypercalcaemia type 1 (IIH) is an autosomal recessive disorder characterised by homozygous mutations in the CYP24A1 gene that encodes the 24-hydroxylase enzyme used to convert active vitamin D metabolites such as 1,25-(OH)2-vitamin D into their inactive form. IIH should be questioned in individuals presenting with a history of unexplained hypercalcaemia, especially if presenting from childhood and/or where there is an accompanying family history of the same in first and/or second degree relatives, causing complications such as nephrocalcinosis, pericarditis, and calcium-based nephrolithiasis. Associated biochemistry of IIH is persistent mild to moderate hypercalcaemia, normal or raised 25-(OH)-vitamin D and elevated 1,25-(OH)2-vitamin D. An elevated ratio of 25-(OH)-vitamin D to 24,25-(OH)2-vitamin D can be a useful marker of defects in the 24-hydroxylase enzyme, whose measurement can be facilitated through the supra-regional assay service. Management should focus on limiting the amount of vitamin D introduced into the body either via sunlight exposure or supplementation in addition to calcium dietary restriction to try and maintain appropriate calcium homeostasis

AbstractA conventional light management approach on a photo-catalyst is to concentrate photo-intensity to enhance the catalytic rate. We present a counter-intuitive approach where light intensity is distributed below the electronic photo-saturation limit under the principle of light maximization. By operating below the saturation point of the photo-intensity induced hydroxide growth under reactant gaseous H2+CO2 atmosphere, a coating of defect engineered In2O3-x(OH)y nanorod Reverse Water Gas Shift solar-fuel catalyst on an optical waveguide outperforms a coated plane by a factor of 2.2. Further, light distribution along the length of the waveguide increases optical pathlengths of the weakly absorptive green and yellow wavelengths, which increases CO product rate by a factor of 8.1-8.7 in the visible. Synergistically pairing with thinly doped silicon on the waveguide enhances the CO production rate by 27% over the visible. In addition, the persistent photoconductivity behavior of the In2O3-x(OH)y system enables CO production at a comparable rate for 2 h after turning off photo-illumination, enhancing yield with 44-62% over thermal only yield. The practical utility of persistent photocatalysis was demonstrated through outdoor solar concentrator tests, which after a day-and-night cycle showed CO yield increase of 19% over a day-light only period.

Background: The rupture of the suture in the abdominal wall, but with integrity of the cutaneous suture, results in a condition known as incisional hernia. It is characterized by the protrusion of the abdominal viscera through orifices or areas of the abdominal wall. In most of the cases these defects in the abdominal wall are iatrogenic. The incisional hernia occurs in an intact wall that is weakened by surgical incisions. The available literature on the incidence of incisional hernias in animals is scarce. With the aim to contribute to the information about incisional hernia in animals, it was decided to describe the case of incisional hernia in a female dog after performing ovariohysterectomy (OH).Case: An adult mongrel shelter bitch, of unknown age, weighing 9.5 kg was admitted for OH in a practical class of the veterinary surgical technical discipline. Once the anesthetic condition was established, a retro-umbilical cutaneous incision was made. After opening the abdominal cavity, the bitch was castrated routinely. The abdominal wall was sutured including peritoneum, muscle fascia, and rectus abdominis muscle with nylon thread and U-stitches. The subcutaneous tissue was then sutured with the same thread using Cushing suture. Ten days after the surgery, when the stitches were removed, the bitch revealed an increase in volume at the region of the surgical scar. Incisional hernia was diagnosed after careful palpation. For correction of the hernia, the bitch was submitted to surgical procedure. After the skin opening, an intense inflammatory reaction was observed in the subcutaneous tissue. The inflamed skin and subcutaneous tissue were removed. The abdominal cavity was closed with nylon thread by means of U-stitches. The subcutaneous and skin sutures were the same as the first surgery. Ten days after the second surgery, stitches were removed, and the bitch had fully recovered. Discussion: One of the factors that may have contributed to the occurrence of the hernia was carrying out the surgical procedure in a practical class. The difficulties shown by students are related to the long learning curve, the complexity of the invasive technique, and the lack of ability. The apprentice surgeon can cause injuries in the tissues due to excessive manipulation. Post-incision hernias are acquired and formed when a cavity wall closed by surgery is ruptured. Another factor that may have contributed to the occurrence of the hernia described here is unsatisfactory postoperative care, which may be considered as one of the factors for acute cases of incisional hernias. Information on postoperative care after the patient was returned to the shelter is not available. Therefore, it cannot be ruled out that the patient, in contact with other animals by means of games or even fights, could have ruptured the points, thus causing dehiscence of the suture in the abdominal wall. However, it was concluded that the most probable factors involved in the etiology of the hernia in question were nutritional deficiencies along with the inexperience of the surgeon. The treatment adopted in the patient (herniorrhaphy) was adequate for the correction of the hernia. The technique and the material to be used in the procedure are of great importance, since it must be resistant enough to avoid recurrences. In the patient in question, nylon thread was used in separate U-shaped stitches. In the literature, there are reports that unabsorbable yarns used at separate points present the lowest rate of dehiscence and relapse in the abdominal wall sutures. The incisional hernia can be prevented by preparing the patient for surgery, improving the nutritional requirements, and by a more intense training of the students performing the surgical procedure in the neutering program of dogs and cats during practical classes.

In a recent book, the neuroscientist Antonio Damasio used the phrase “No body, never mind” to sum up the ways in which Spinoza prefigured much recent neurobiology in his conception of a psychophysical parallelism. As Damasio (213) explains, Spinoza “is stating that the idea of an object in a given mind cannot occur without the existence of the body; or without the occurrence of certain modifications on that body as caused by the object, No body, never mind”. Given that education is generally understood as a cognitive process with a focus on the mind at the expense of the body, Spinoza’s insights are particularly interesting. We tend to forget the bodily dimension of learning; how, as children beginning to write, we had to labour over forming letters, using the appropriate pen grip and sitting correctly. While the physicality of literate practice may have long since been obscured by the habituation of these skills, at times we are still reminded of the visceral nature of learning, such as, when we have to apply ourselves to a task but lack the motivation to do so. I know that I develop an unsettled feeling, a certain restlessness, that seems to pervade my body leading me to engage in a range of diversionary tactics such as ringing a friend, making a coffee or rechecking my email. I don’t seem to be able to muster the physical effort to apply myself; I simply lack the necessary interest to start work. To the psychologist, Silvan Tomkins, interest is crucial. Coupled with excitement, it is one of the nine affects he identifies as innate to humans. He explains, “without interest the development of thinking and the conceptual apparatus would be seriously impaired” (Tomkins 343). As an affect, interest has a physiological basis and it is with this that I want to engage. Drawing briefly on an empirical study related to these issues in primary school classrooms, I want to examine how interest is generated by the particular practices that teachers employ. While my focus is the early years of school, this study has relevance to all levels of education. With innovation in this area conceived in terms of on-line delivery (Brabazon) and student-directed learning, contemporary pedagogy is witnessing a marginalisation of the teacher (McWilliam). What I want to do here is to reassert the importance of their role by demonstrating how teachers can engender interest and to consider the ways this affects student learning. In his discussion of interest, Tomkins begins by making reference to Darwin’s work on emotions, a term Tomkins avoids in favour of affect (1). He points out that while Darwin managed to catalogue surprise and meditation, he neglected to include interest within his typology. Tomkins feels this omission was a result of Darwin misinterpreting the affect, viewing the interest and excitement he invested in his work as simply a function of thinking. Darwin’s mistake was to fuse the corporeal with the cognitive or, rather, to collapse the former into the latter, ignoring how thought arises, as Spinoza points out, from some impact or modification of the body. This should not be understood in terms of simple causality or an account of the interaction between body and mind. As Spinoza (2) explains, “the body cannot determine the mind to thinking and the mind cannot determine the body to motion, to rest, or to anything else”. As far as Spinoza was concerned, the mind and the body are one and the same thing (7S). They exist in an isomorphic relation which allows for an analytic distinction to be made between the two. Spinoza’s ontology meshes nicely with Tomkins’ notion of affect. As Gibbs (340) writes in her account of Tomkins, he “makes clear that there can be no ‘pure cognition’ no cognition uncontaminated by the richness of the sensate experience, including affective experience”. Thought, therefore, can be understood as a product of affect; a function of our bodily reactions to everyday experience. While there is considerable complementarity between Spinoza and Tomkins in terms of affect and conceptions of the mind/body relation, what I find particularly useful about Spinoza is that in his discussion of affect he makes a distinction between what he calls affectus and affectio. The former refers to the force or the impact of an affecting body; the latter denotes the actual state of the affected body: affect as process and product (Deleuze 49). This seems a useful distinction in theorising pedagogy as it provides a mechanism for understanding how what teachers do in classrooms impacts upon students’ bodies and minds. The notion of affectio also seems to imply that affects are not fleeting – having only transitory effect – although they may be. Rather, it suggests affects can accumulate to become dispositions providing, at one and the same time, the content of mind and the impetus for action. Although never providing any detailed elaboration of these ideas, the early 20th century Russian psychologist, Lev Vygotsky, displayed a similar interest in affect. A leading figure in the field of child language development, Vygotsky (Collected Works 50) was interested in the relationship between intellect and affect. He remarked that, “Among the most basic defects of traditional approaches to the study of psychology has been the isolation of the intellectual from the volitional and affective aspects of consciousness”. Vygotsky was critical of psychology’s neglect of the body and found Spinoza’s psychophysical parallelism and his notion of affect useful in explaining how consciousness functions as an embodied phenomenon (Vygotsky, Emotions). Within education, however, Vygotsky is best known for his theory of the Zone of Proximal Development (ZPD) which refers to the gap between children’s actual development determined by independent problem solving and their potential development achieved when assisted (Vygotsky, Thought 187). The form of assistance Vygotsky intended was not simply that which results from peer collaboration. Although he felt the support of more knowledgeable peers could be beneficial, he placed strong emphasis on the role of the teacher and the power of instruction (Vygotsky, Thought 157). This relationship between affect and the ZPD is particularly interesting yet, due to his untimely death, this was something Vygotsky was never able to pursue. It seems possible, however, that the enhanced performance a child achieves when assisted could be related to the interest that a teacher induces given, as Tomkins explains, that interest has “a physiological function as an aid to sustained effort” (Tomkins 33). It was these ideas that came to mind as I was interviewing one of fifteen teachers as part of a study into teaching desire. As less and less emphasis seems to be placed on whole-class instruction, with a preference for independent and group-based learning, I was keen to investigate which pedagogic modes teachers considered the most effective and which gave them the greatest sense of satisfaction. I began by asking teachers about their practice and having them identify their pedagogy as being either more teacher or student-directed. As with most of the teachers in the study, Nerida, a Year 2 teacher, saw her approach to teaching as more student-directed or progressivist in design. She displayed a reluctance to foreground her role in the classroom and her involvement in her students’ learning. As the interview progressed, however, and she began to discuss specific examples of her practice, it became clear that her desire to teach was more obviously realised through whole-class instruction; the actual performance of teaching and engaging with students. She took great delight in describing a lesson on syllable poems that had taken place on the day of the interview. She explained, today it was just one of those lessons where it was like, ‘Wow’, I wish everyday was like that. And, we made one up together and they were coming up with all these fantastic descriptive words and this whole year I’ve been drumming it into them. She then provided more detail about her role in the lesson: Well, we made it quite fun. Like I was hopping in and out of them and walking in amongst them and I‘m going, ‘Okay, what’s another descriptive word about this?’, and then they would all cheer and I’d write it on the board. And do you know what I mean? I suppose it is your personality that comes through. In explaining the effect of the lesson on both herself and the class, she pointed out that you have the same feeling I think as the kids because they are excited about a particular activity, or a particular experience and you think ‘Oh’! You are excited for them because what you wanted them to learn is what they’re actually learning … Yeah. And so they did it and it was just like you could see the kids’ faces. I mean I know it’s like the cliché thing but you could just tell that they were so into it. In her account of this lesson Nerida effectively captures the way in which her pedagogy impacts upon her students. In teaching the class she was not only assisting them to arrive at a bank of words they could use in their own poems, with this input acting as an aid to cognition, the highly performative nature of her delivery imbued her students with the interest to engage in the task, with the arousal of this affect providing additional stimulus for academic endeavour. To Nerida, this interest was displayed on her students’ faces, the site on which Tomkins explains, affect is most clearly evident. While Nerida is probably referring to the students’ wide-eyed smiles, an expression of their joy at her performance, Tomkins points out how a faraway look may also be diagnostic of interest signalling an individual is tracking a memory or idea and is engaged in exploring her/his own thoughts (Tomkins 339). This point is significant in relation to criticisms of teacher-directed learning as passive pedagogy. It suggests that even without the kind of enthusiastic delivery that Nerida provides, instruction can be interesting with passivity indicating cognitive activity rather than a lack of engagement in learning. The interest that Nerida encourages in her students also seems a function of contagion. Tomkins (297) and more recently Brennan explore this aspect of affect and it seems of particular relevance within a classroom context. The intercorporeal dynamic of teacher and students is heightened with a mass of bodies participating in a common activity. Interest is intensified by the corporate nature of learning which, given Nerida’s comments, seemed to provide the necessary stimulus for students to then complete their work on an individual basis. It is important to note, however, that it is not only this single performance by Nerida that enables her students to successfully complete their work. Their interest needs to be sustained and this is dependent on students already possessing the ability to complete the task. Interest and ability operate in tandem and it is the accumulation of interest that supplies the necessary effort to acquire ability. In addition to igniting her students’ interest, Nerida supplied the foundation whereby this affect would prove effective. As she explains, “this whole year I’ve been drumming it into them”. Students could write expressive poems as they had embodied the knowledge to do so and the pedagogy their teacher employed ensured they had the interest required to apply what they had learned. The affects that Nerida generated have a corporeal basis and it is this affective transaction between teacher and student that provided the impetus for learning. In theorising pedagogy it is useful to consider the bodily nature of learning and to engage with what Damasio points out, namely, “No body, never mind”. References Brabazon, Tara. Digital Hemlock. Sydney: UNSW Press, 2002. Brennan, Teresa. The Transmission of Affect. Ithaca: Cornell UP, 2004. Damasio, Antonio. Looking for Spinoza: Joy, Sorrow and the Feeling Brain. London: William Heinemann, 2003. Deleuze, Gilles. Spinoza: Practical Philosophy. Trans. Robert Hurley. San Francisco: City Lights Books, 1988. Gibbs, Anna. “Disaffected.” Continuum: Journal of Media and Cultural Studies 16.3 (2002): 335-41. McWilliam, Erica. “Admitting Impediments: Or Things to Do with Bodies in the Classroom.” Cambridge Journal of Education 26.2 (1996): 367-78. Probyn, Elspeth. Blush, Faces of Shame. Sydney: UNSW Press, 2005. Spinoza, Baruch. “The Ethics.” In E. Curley (Ed. & Trans.), A Spinoza Reader: The Ethics and Other Works: Benedict de Spinoza. Princeton: Princeton UP, 1994. Tomkins, Silvan. Affect, Imagery and Consciousness. New York: Springer, 1962. Vygotsky, Lev. “Spinoza’s Theory of the Emotions in Light of Contemporary Psychoneurology.” Society Studies in Philosophy 10 (1972): 362-82. Vygotsky, Lev. “The Problem and the Method of Investigation.” In R.W. Rieber & A.S. Carton, eds., The Collected Works of L.S. Vygotsky 1 (1987): 43-51. Vygotsky, Lev. Thought and Language. Cambridge, Massachusetts: MIT P, 1996. Citation reference for this article MLA Style Watkins, Megan. "No Body, Never Mind: Interest, Affect and Classroom Practice." M/C Journal 8.6 (2005). echo date('d M. Y'); ?> <http://journal.media-culture.org.au/0512/06-watkins.php>. APA Style Watkins, M. (Dec. 2005) "No Body, Never Mind: Interest, Affect and Classroom Practice," M/C Journal, 8(6). Retrieved echo date('d M. Y'); ?> from <http://journal.media-culture.org.au/0512/06-watkins.php>.

The word “prosthetic” has its origins as a mathematical term. According to scholar Brandon W. Hawk, Plato uses the words prosthesis and prostithenai in Phaedo to mean "addition, add to, to place", and Aristotle uses it in a similar, algebraic sense in the Metaphysics. Later, as the word appears in classical Latin, it is used as a grammatical and rhetorical term, in the sense of a letter or syllable that is added on to a word, usually the addition of a syllable to the beginning of a word, hence pro-thesis (Hawk). This is the sense of the word that was “inherited … by early modern humanists”, says Hawk, but when it appears in Edward Phillips's The New World of English Words: Or, a General Dictionary (1706), we can see how, with advances in technology, it changes from a grammatical/linguistic term into a medical term. What was once word is now made flesh:Prosthesis, a Grammatical Figure, when a Letter or Syllable is added to the beginning of a Word, as Gnatus for natus, tetuli for tuli, &c. In Surgery, Prosthesis is taken for that which fills up what is wanting, as is to beseen in fistulous and hollow Ulcers, filled up with Flesh by that Art: Also themaking of artificial Legs and Arms, when the natural ones are lost.Hawk also points to P. Dionis in Course Chirurg (a 1710 textbook detailing the art of chirurgy, or surgery, as it’s known now), who uses the word to denote one type of surgical operation; that is, prosthesis becomes not a word, but an act that “adds what is deficient”, an act that repairs loss, that “fills up what is wanting”, that fills up what is “hollow”, that “fills up with flesh”. R. Brookes, in his Introduction to Physic and Surgery (1754), is the first to define prosthesis as both an act and also as a separate, material object; it is “an operation by which some instrument is added to supply the Defect of a Part which is wanting, either naturally or accidentally”. It is not until the twentieth century (1900, to be exact), though, that the word begins to refer solely to a device or object that is added on to somehow “supply the defect”, or fill up what which is “wanting”. So etymologically we move from the writer creating a new literary device, to the scientist/doctor acting in order to fix something, then back to the device again, this time as tangible object that fills a gap where there is lack and loss (Hawk).This is how we most often see the word, and so we have the notion of prosthetic used in this medicalised sense, as an "instrument", in relation to people with missing or disfunctional limbs. Having a prosthetic arm or leg in an ableist society instantly marks one as "missing" something, or being "disabled". Wheelchairs and other prosthetic accoutrements also serve as a metonymic shorthand for disability (an example of this might be how, on reserved parking spots in North America, the image on the sign is that of a person in a wheelchair). In the case of deaf people, who are also thought of as "disabled", but whose supposed disability is invisible, hearing aids and cochlear implants (CIs) serve as this kind of visible marker.* Like artificial limbs and wheelchairs, these "instruments" (they are actually called “hearing instruments” by audiologists) are sometimes added on to the purportedly “lacking” body. They are objects that “restore function to” the disabled deaf ear. As such, these devices, like wheelchairs and bionic arms, also serve as a shorthand in American culture, especially in film and visual media, where this kind of obvious, material symbolism is very helpful in efficiently driving narrative along. David L. Mitchell and Sharon T. Snyder call this kind of disability shorthand "narrative prosthesis". In their 2001 book of the same name, they demonstrate that disability and the markers of disability, far from being neglected or omitted (as has been claimed by critics like Sarah Ruiz-Grossman), actually appear in literature and film to the point where they are astonishingly pervasive. Unlike other identities who are vastly underrepresented, Mitchell and Snyder note, images of disability are almost constantly circulated in print and visual media (this is clearly demonstrated in older film studies such as John Schuchman's Hollywood Speaks and Martin Norden's Cinema of Isolation, as well). The reason that this happens, Mitchell and Snyder say, is because almost all narrative is structured around the idea of a flaw in the natural order, the resolution of that flaw, and the restoration of order. This flaw, they show, is more often than not represented by a disabled character or symbol. Disability, then, is a "crutch upon which literary narratives lean for their representational power, disruptive potentiality and analytical insight" (49). And, in the end, all narrative is thus dependent upon some type of disability used as a prosthetic, which serves not only to “fill in” lack, but also to restore and reinforce normalcy. They also state that concepts of, and characters with, disability are therefore used in literature and film primarily as “opportunist metaphorical device(s)” (205). Hearing aids and CIs are great examples of "opportunist" devices used on television and in movies, mostly as props or “add-ons” in visual narratives. This "adding on" is done, more often than not, to the detriment of providing a well rounded narrative about the lived experience of deaf people who use such devices on a daily basis. There are countless examples of this in American television shows and films (in an upward trend since 2000), including many police and crime dramas where a cochlear implant device-as-clue stands in for the dead victim’s identity (Kincheloe "Do Androids"). We see it in movies, most notably in 2018’s A Quiet Place, in which a CI is weaponized and used to defeat the alien monster/Other (as opposed to the deaf heroine doing it by herself) (Kincheloe "Tired Tropes"). In 2019's Toy Story 4, there is a non-signing child who we know is deaf because they wear a CI. In the 2019 animated Netflix series, Undone, the main character wears a CI, and it serves as one of several markers (for her and the viewer) of her possible psychological breakdown.It seems fairly obvious that literal prostheses such as hearing aids and CI devices are used as a form of media shorthand to connote hearing ideas of “deafness”. It also might seem obvious that, as props that reinforce mainstream, ableist narratives, they are there to tell us that, in the end, despite the aesthetic nervousness that disability produces, "things will be okay". It's "fixable". These are prosthetics that are easily identified and easily discussed, debated, and questioned.What is perhaps not so obvious, however, is that American Sign Language (ASL), is also used in media as a narrative prosthetic. Lennard Davis' discussion of Erving Goffman’s idea of “stigma” in Enforcing Normalcy supports the notion that sign language, like hearing aids, is a marker. When seen by the hearing, non-signing observer, sign language "stigmatizes" the signing deaf person (48). In this sense, ASL is, like a hearing aid, a tangible "sign" of deaf identity. I would then argue that ASL is, like hearing aids and CIs, used as a "narrative prosthesis" signifying deafness and disability; its insertion allows ableist narratives to be satisfyingly resolved. Even though ASL is not a static physical device, but a living language and an integral part of deaf lived experience, it is casually employed almost everywhere in media today as a cheap prop, and as such, serves narrative purposes that are not in the best interest of realistic deaf representation. Consider this example: On 13 April 2012, Sir Paul McCartney arranged for a special event at his daughter Stella McCartney’s ivy-covered store in West Hollywood. Stars and friends like Jane Fonda, Gwyneth Paltrow, Chris Martin, Quincy Jones, and Reese Witherspoon sipped cucumber margaritas and nibbled on a spread of vegetarian Mexican appetizers. Afterwards, McCartney took them all to a tent set up on the patio out back, where he proudly introduced a new video, directed by himself. This was the world premiere of the video for "My Valentine", a song from his latest (some might say oddly titled) album, Kisses from the Bottom, a song he had originally written for and sung to new wife Nancy Shevell, at their 2011 wedding.The video is very simply shot in black and white, against a plain grey backdrop. As it begins, the camera fades in on actor Natalie Portman, who is seated, wearing a black dress. She stares at the viewer intently, but with no expression. As McCartney’s voiced-over vocal begins, “What if it rained/We didn’t care…”, she suddenly starts to mouth the words, and using sign language. The lens backs up to a medium shot of her, then closes back in on a tight close up of just her hands signing “my valentine” on her chest. There is then a quick cut to actor Johnny Depp, who is sitting in a similar position, in front of a grey backdrop, staring directly at the camera, also with no expression. There is a fade back to Portman’s face, then to her body, a close up of her signing the word “appear”, and then a cut back to Depp. Now he starts signing. Unlike Portman, he does not mouth the words, but stares ahead, with no facial movement. There is then a series of jump cuts, back and forth, between shots of the two actors’ faces, eyes, mouths, hands. For the solo bridge, there is a closeup on Depp’s hands playing guitar – a cut to Portman’s face, looking down – then to her face with eyes closed as she listens. here is some more signing, we see Depp’s impassive face staring at us again, and then, at the end, the video fades out on Portman’s still figure, still gazing at us as well.McCartney told reporters that Stella had been the one to come up with the idea for using sign language in the video. According to the ASL sign language coach on the shoot, Bill Pugin, the choice to include it wasn’t that far-fetched: “Paul always has an interpreter on a riser with a spot for his concerts and Stella loves sign language, apparently” ("The Guy Who Taught Johnny Depp"). Perhaps she made the suggestion because the second stanza contains the words “I tell myself that I was waiting for a sign…” Regardless, McCartney advised her father to “ring Natalie up and just ask her if she will sign to your song”. Later realizing he wanted another person signing in the video, Paul McCartney asked Johnny Depp to join in, which he did. When asked why he chose those two actors, McCartney said, “Well, they’re just nice people, some friends from way back and they were just very kind to do it”. A week later, they all got together with cinematographer Wally Pfister, who filmed Inception and The Dark Knight, behind the camera. According to the official press release about the video, posted on McCartney’s website, the two actors then "translate[d] the lyrics of the song into sign language – each giving distinctly different performances, making ... compelling viewing" ("Paul McCartney Directs His Own"). The response to the video was quite positive; it immediately went viral on YouTube (the original posting of it got over 15 million views). The album made it to number five on the Billboard charts, with the single reaching number twenty. The album won a 2013 Grammy Award for Best Traditional Pop Vocal album, and the video Best Music Film (“Live Kisses”). McCartney chose to sing that particular song from the album on the award show itself, and four years later, he featured both the song and video as part of his 31 city tour, the 2017 One on One concert, in which he made four million dollars a city. All told the video has served McCartney quite well.But…For whom the sign language? And why? The video is not meant for deaf eyes. When viewed through a deaf lens, it is not, by any stretch of the imagination, “compelling”; it isn’t even comprehensible. It is so bad, in fact, that the video, though signed, is also captioned for the deaf and hard of hearing. To the untrained, “hearing” eye, the signing seems to be providing a “deaf translation” of what is being sung. But it is in fact a pantomime. The actors are quite literally “going through the motions”. One egregious example of this is how, at the end of the video, when Depp thinks he’s signing “valentine”. it looks like he's saying “fuck-heart” (several media sources politely reported that he’d signed “enemy”). Whatever he did, it’s not a sign. In response to criticism of his signing, Depp said nonchalantly, “Apparently, instead of ‘love' I might have said, ‘murder'” ("Johnny Depp Says"). That wasn’t the only point of confusion, though: the way Portman signs “then she appears” was misunderstood by some viewers to be the sign for “tampon”. She actually signed it correctly, but media sources from MTV.com, to the Washington Post, “signsplained” that she had just gotten a bit confused between ASL and BSL signs (even though the BSL for “appears” bears no resemblance to what she did, and the ASL for tampon, while using the same classifier, is also signed quite differently). Part of the problem, according to sign coach Pugin, was that he and Depp “had about fifteen minutes to work on the song. I signed the song for hours sitting on an apple box under the camera for Johnny to be able to peripherally see me for each take. I was his “human cue card”. Johnny’s signing turned out to be more theatrical and ‘abbreviated’ because of the time issue” ("The Guy Who Taught").Portman, perhaps taking more time to rehearse, does a better job, but “theatrical and abbreviated” indeed; the signing was just not good, despite Pugin's coaching. But to hearing eyes, it looks fine; it looks beautiful, it looks poignant and somehow mysterious. It looks the way sign language is “supposed” to look.Remember, the McCartney website claimed that the actors were “translating” the lyrics. Technically speaking, “translation” would mean that the sense of the words to the song were being rendered, fluently, from one language (English) into another (SL), for an audience receptive to the second language. In order to “translate”, the translator needs to be fluent in both of the languages involved. To be clear, what Depp and Portman were doing was not translation. They are hearing people, not fluent in sign language, acting like signers (something that happens with dismaying regularity in the entertainment industry). Depp, to his credit, knew he wasn’t “translating”, in fact, he said "I was only copying what the guy showed me”. “But”, he says, "it was a gas – sign language is apparently very interpretive. It's all kind of different" (italics mine) ("Johnny Depp Passes the Buck"). Other than maybe being an embellishment on that one line, “I tell myself that I was waiting for a sign…”, the sentiments of McCartney’s song have absolutely nothing to do with ASL or deaf people. And he didn’t purposefully place sign language in his video as a way to get his lyrics across to a deaf audience. He’s a musician; it is fairly certain that the thought of appealing to a deaf audience never entered his or his daughter’s mind. It is much more likely that he made the decision to use sign language because of its cool factor; its emo “novelty”. In other words, McCartney used sign language as a prop – as a way to make his song “different”, more “touching”, more emotionally appealing. Sign adds a je ne sais quoi, a little “something”, to the song. The video is a hearing person’s fantasy of what a signing person looks like, what sign language is, and what it does. McCartney used that fantasy, and the sentimentality that it evokes, to sell the song. And it worked. This attitude toward sign language, demonstrated by the careless editing of the video, Depp’s flippant remarks, and the overall attitude that if it’s wrong it’s no big deal, is one that is pervasive throughout the entertainment and advertising industries and indeed throughout American culture in the U.S. That is, there is this notion that sign language is “a gas”. It’s just a “different” thing. Not only is it “different”, but it is also a “thing”, a prop, a little exotic spice you throw into the pot. It is, in other words, a "narrative prosthesis", an "add-on". Once you see this, it becomes glaringly apparent that ASL is not viewed in mainstream American culture as the language of a group of people, but instead is widely used and commodified as a product. The most obvious form of commodification is in the thousands of ASL products, from Precious Moment figurines, to Baby Signing videos, to the ubiquitous “I LOVE YOU” sign seen on everything from coffee mugs to tee shirts, to Nike posters with “Just Do It” in fingerspelling. But the area in which the language is most often commodified (and perhaps most insidiously so) is in the entertainment industry, in visual media, where it is used by writers, directors and actors, not to present an accurate portrait of lived deaf experience and language, but to do what Paul McCartney did, that is, to insert it just to create a “different”, unique, mysterious, exotic, heartwarming spectacle. Far too often, this commodification of the language results in weirdly distorted representations of what deaf people and their language actually are. You can see this everywhere: ASL is a prominent narrative add-on in blockbuster films like the aforementioned A Quiet Place; it is used in the Oscar winning The Shape of Water, and in Wonderstruck, and Baby Driver as well; it is used in the indie horror film Hush; it is used in a lot of films with apes (the Planet of the Apes series and Rampage are two examples); it is displayed on television, mostly in police dramas, in various CSI programs, and in series like The Walking Dead and Castle Rock; it is used in commercials to hawk everything from Pepsi to hotel chains to jewelry to Hormel lunchmeat to fast food (Burger King, Chik Fil A); it is used and commented on in interpreted concerts and music videos and football halftime shows; it is used (often misused) in PSAs for hurricanes and police stops; it is used in social media, from vlogs to cochlear implant activation videos. You can find ASL seemingly everywhere; it is being inserted more and more into the cultural mainstream, but is not appearing as a language. It is used, nine times out of ten, as a decorative ornament, a narrative prop. When Davis discusses the hearing perception of ASL as a marker or visible stigma, he points out that the usual hearing response to observing such stigma is a combination of a Freudian attraction/repulsion (the dominant response being negative). Many times this repulsion results from the appeal to pathos, as in the commercials that show the poor isolated deaf person with the nice hearing person who is signing to them so that they can now be part of the world. The hearing viewer might think to themselves "oh, thank God I'm not deaf!"Davis notes that, in the end, it is not the signer who is the disabled one in this scenario (aside from the fact that many times a signing person is not in fact deaf). The hearing, non signing observer is actually the one “disabled” by their own reaction to the signing “other”. Not only that, but the rhetorical situation itself becomes “disabled”: there is discomfort – wariness of language – laughter – compulsive nervous talking – awkwardness – a desire to get rid of the object. This is a learned response. People habituated, Davis says, do not respond this way (12-13). While people might think that the hearing audience is becoming more and more habituated because ASL is everywhere, the problem is that people are being incorrectly habituated. More often than not, sign language, when enfolded into narratives about hearing people in hearing situations, is put into service as a prop that can mitigate such awkward moments of possible tension and conflict; it is a prosthetic that "fills the gap", allowing an interaction between hearing and deaf people that almost always allows for a positive, "happy" resolution, a return to "normalcy", the very purpose of the "narrative prosthetic" as posited by Mitchell and Snyder. Once we see how ASL is being employed in media mostly as a narrative prosthesis, we can, as Mitchell and Snyder suggest we do (what I hope this essay begins to do), and that is, to begin to “undo the quick repair of disability in mainstream representations and beliefs; to try to make the prosthesis show; to flaunt its imperfect supplementation as an illusion” (8). In other words, if we can scrutinize the shorthand, and dig deeper, seeing the prosthetic for what it is, all of this seemingly exploitative commodification of ASL will be a good thing. Maybe, in “habituating” people correctly, in widening both hearing people’s exposure to ASL and their understanding of its actual role in deaf lived experience, signing will become less of a prosthetic, an object of fetishistic fascination. Maybe hearing people, as they become used to seeing signing people in real signing situations, will be less likely to walk up to deaf people they don’t know and say things like: “Oh, your language is SO beautiful”, or say, “I know sign!” (then fingerspelling the alphabet with agonising slowness and inaccuracy while the deaf person nods politely). However, if the use of ASL as a prosthetic in popular culture and visual media continues to go on unexamined and unquestioned, it will just continue to trivialise a living, breathing language. This trivialisation can in turn continue to reduce the lived experiences of deaf people to a sort of caricature, further reinforcing the negative representations of deaf people in America that are already in place, stereotypes that we have been trying to escape for over 200 years. Note* The word "deaf" is used in this article to denote the entire range of individuals with various hearing losses and language preferences, including Deaf persons and hard of hearing persons, etc. For more on these distinctions please refer to the website entry on this published by the National Association of the Deaf (NAD).ReferencesDavis, Lennard. Enforcing Normalcy. New York: Verso, 1995."The Guy Who Taught Johnny Depp and Natalie Portman Sign Language." Intimate Excellent: The Fountain Theater Blog. 18 Mar. 2012. <https://intimateexcellent.com/2012/04/18/the-guy-who-taught-johnny-depp-and-natalie-portman-sign-language-in-mccartney-video/>.Fitzgerald, Roisin. "Johnny Depp Says Sign Language Mishap Isn't His Fault." HiddenHearing Blog 14 Apr. 2012. <https://hiddenhearingireland.wordpress.com/2012/05/29/johnny-depp-says-sign-language-mishap-isnt-his-fault/>.Hawk, Brandon W. “Prosthesis: From Grammar to Medicine in the Earliest History of the Word.” Disability Studies Quarterly 38.4 (2018).McCartney, Paul. "My Valentine." YouTube 13 Apr. 2012.McGinnis, Sara. "Johnny Depp Passes the Buck on Sign Language Snafu." sheknows.com 10 May 2012. <https://www.sheknows.com/entertainment/articles/959949/johnny-depp-passes-the-buck-on-sign-language-snafu/>.Miller, Julie. "Paul McCartney on Directing Johnny Depp and Natalie Portman." Vanity Fair 14 Apr. 2012. <https://www.vanityfair.com/style/2012/04/paul-mccartney-johnny-depp-natalie-portman-my-valentine-music-video-gwyneth-paltrow>.Mitchell, David T., and Sharon L. Snyder. Narrative Prosthesis: Disabilities and the Dependencies of Discourse. Ann Arbor: U of Michigan P. 2000.Norden, Martin. F. The Cinema of Isolation: A History of Physical Disability in Movies. Rutgers UP: 1994."Paul McCartney Directs His Own My Valentine Video." paulmccartney.com 14 Apr. 2012. <https://www.paulmccartney.com/news-blogs/news/paul-mccartney-directs-his-own-my-valentine-videos-featuring-natalie-portman-and>.Ruiz-Grossman, Sarah. "Disability Representation Is Seriously Lacking in Television and the Movies: Report." Huffington Post 27 Mar. 2019. <https://www.huffpost.com/entry/disability-representation-movies-tv_n_5c9a7b85e4b07c88662cabe7>.Schuchman, J.S. Hollywood Speaks: Deafness and the Film Entertainment Industry. U Illinois P, 1999.