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1
Pickens, Rebecca Crinean. "Michael Vick’s Pit Bulls & Dogfighting: Ramifications of Media Coverage." Journal of Student Research 2, no. 1 (May 31, 2013): 17–21. http://dx.doi.org/10.47611/jsr.v2i1.137.
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According to The Humane Society of the United States from 2006 to 2008 there were more than 3,000 pit bulls removed from dogfighting rings. The majority of surviving dogs were euthanized upon confiscation by authorities. The purpose of this research was to examine the possible impact of Michael Vick’s dogfighting case on print media coverage of pit bull-type dogs. The research questions were whether the extensive coverage of his dogfighting charges would change how media portray these dogs, and whether the issue of dogfighting would become a more widely-covered topic. The research process included a literature review of scholarly works written about pit bulls, and a qualitative analysis of articles from The New York Times, The Wall Street Journal, and USA Today published one year before and after the Vick case broke, using “pit bull” as the key phrase. Articles were divided into different categories depending on the contextual use of the term “pit bull.” Findings were based on the analysis of those categories. The results indicated positive portrayals of pit bulls and discussions of dogfighting were primarily isolated to the coverage of Vick’s case and dogs. The more than 200 other recorded raids on dogfighting rings that same year went unmentioned, but six stories about aggressive pit bull-type dogs were covered. This indicates media coverage of pit bulls did not change. Media can learn there is more to cover than limiting the focus on celebrity dogfighters and the cliché of pit bulls as vicious. These changes in coverage could lead to an overall positive change in the public’s perception of pit bull-type dogs.
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Fomin, Sergey, and George Lusztig. "Coordinate rings and birational charts." Representation Theory of the American Mathematical Society 26, no. 1 (January 5, 2022): 1–16. http://dx.doi.org/10.1090/ert/592.
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Let G G be a semisimple simply connected complex algebraic group. Let U U be the unipotent radical of a Borel subgroup in G G . We describe the coordinate rings of U U (resp., G / U G/U , G G ) in terms of two (resp., four, eight) birational charts introduced by Lusztig [Total positivity in reductive groups, Birkhäuser Boston, Boston, MA, 1994; Bull. Inst. Math. Sin. (N.S.) 14 (2019), pp. 403–459] in connection with the study of total positivity.
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NASR-ISFAHANI, A. R. "REVERSIBLE SKEW GENERALIZED POWER SERIES RINGS." Bulletin of the Australian Mathematical Society 84, no. 3 (July 21, 2011): 455–57. http://dx.doi.org/10.1017/s0004972711002450.
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AbstractIn this note we show that there exist a semiprime ring R, a strictly ordered artinian, narrow, unique product monoid (S,≤) and a monoid homomorphism ω:S⟶End(R) such that the skew generalized power series ring R[[S,ω]] is semicommutative but R[[S,ω]] is not reversible. This answers a question posed in Marks et al. [‘A unified approach to various generalizations of Armendariz rings’, Bull. Aust. Math. Soc.81 (2010), 361–397].
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Danchev, Peter V. "Quasi invo-clean rings." Bulletin of the Transilvania University of Brasov Series III Mathematics and Computer Science 1(63), no. 1 (October 7, 2021): 71–80. http://dx.doi.org/10.31926/but.mif.2021.1.63.1.6.
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An element v of an arbitrary ring R is called aninvolution if v2= 1 and a quasi-involution if either v or 1−vis an involution. We thereby define R to be quasi invo-cleanas the one whose elements are written in the form ofa sum of an idempotent and a quasi-involution. This considerably extends the class of invo-clean rings introduced by the present author in Commun. Korean Math. Soc. (2017) and the class of weakly tripotent rings introducedby Breaz and Cˆımpean in Bull. Korean Math. Soc. (2018). We, more-over, prove the curious fact that the newly defined class of quasi invo-cleanrings actually coincides with the class of weakly invo-clean rings defined by Danchev in Afr. Mat. (2017).
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Izelgue, L., and O. Ouzzaouit. "Hilbert rings and G(oldman)-rings issued from amalgamated algebras." Journal of Algebra and Its Applications 17, no. 02 (January 23, 2018): 1850023. http://dx.doi.org/10.1142/s0219498818500238.
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Let [Formula: see text] and [Formula: see text] be two rings, [Formula: see text] an ideal of [Formula: see text] and [Formula: see text] be a ring homomorphism. The ring [Formula: see text] is called the amalgamation of [Formula: see text] with [Formula: see text] along [Formula: see text] with respect to [Formula: see text]. It was proposed by D’anna and Fontana [Amalgamated algebras along an ideal, Commutative Algebra and Applications (W. de Gruyter Publisher, Berlin, 2009), pp. 155–172], as an extension for the Nagata’s idealization, which was originally introduced in [Nagata, Local Rings (Interscience, New York, 1962)]. In this paper, we establish necessary and sufficient conditions under which [Formula: see text], and some related constructions, is either a Hilbert ring, a [Formula: see text]-domain or a [Formula: see text]-ring in the sense of Adams [Rings with a finitely generated total quotient ring, Canad. Math. Bull. 17(1) (1974)]. By the way, we investigate the transfer of the [Formula: see text]-property among pairs of domains sharing an ideal. Our results provide original illustrating examples.
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Boua, A., L. Oukhtite, and A. Raji. "On generalized semiderivations in 3-prime near-rings." Asian-European Journal of Mathematics 09, no. 02 (April 15, 2016): 1650036. http://dx.doi.org/10.1142/s1793557116500364.
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There is a large body of evidence showing that the existence of a suitably-constrained derivation on a 3-prime near-ring forces the near-ring to be a commutative ring. The purpose of this paper is to study generalized semiderivations which satisfy certain identities on 3-prime near-ring and generalize some results due to [H. E. Bell and G. Mason, On derivations in near-rings, North-Holland Math. Stud. 137 (1987) 31–35; H. E. Bell, On prime near-rings with generalized derivation, Int. J. Math. Math. Sci. 2008 (2008), Article ID: 490316, 5[Formula: see text]pp; A. Boua and L. Oukhtite, Some conditions under which near-rings are rings, Southeast Asian Bull. Math. 37 (2013) 325–331]. Moreover, an example is given to prove that the necessity of the 3-primeness hypothesis imposed on the various theorems cannot be marginalized.
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Danchev, Peter. "Isomorphism Characterization of Divisible Groups in Modular Abelian Group Rings." gmj 16, no. 1 (March 2009): 49–54. http://dx.doi.org/10.1515/gmj.2009.49.
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Abstract Suppose G is an abelian group with a p-subgroup H and R is a commutative unitary ring of prime characteristic p with trivial nil-radical. We give a complete description up to isomorphism of the maximal divisible subgroups of 1 + I(RG;H) and (1 + I(RG;H))=H, respectively, where I(RG;H) denotes the relative augmentation ideal of the group algebra RG with respect to H. This paper terminates a series of works by the author on the topic, first of which are [Danchev, Rad. Mat. 13: 23–32, 2004] and [Danchev, Bull. Georgian Acad. Sci. 174: 238–242, 2006].
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ANDRUSZKIEWICZ, R. R., and M. WORONOWICZ. "ON SI-GROUPS." Bulletin of the Australian Mathematical Society 91, no. 1 (September 12, 2014): 92–103. http://dx.doi.org/10.1017/s0004972714000641.
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AbstractThis paper presents new results concerning the structure of $\text{SI}$-groups and refines and purifies the results obtained in this field by Shalom Feigelstock [‘Additive groups of rings whose subrings are ideals’, Bull. Aust. Math. Soc.55 (1997), 477–481]. The structure theorem describing torsion-free $\text{SI}$-groups is proved in the associative case. Numerous examples of $\text{SI}$-groups are given. Some inconsistencies in Feigelstock’s article are noted and corrected.
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Chatterjee, Tapan K. "The Character of Embedded Rings." Symposium - International Astronomical Union 186 (1999): 194. http://dx.doi.org/10.1017/s0074180900112549.
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It is well known that, under favorable conditions, tidal interactions between a spiral galaxy and a more compact elliptical leads to the formation of embedded rings in the disk (e.g. Chatterjee 1979, Bull. Astron. Soc. India, 7, 32); in addition there are also nuclear rings whcih do not seem to have a tidal origin (e.g. Buta 1986, ApJ, 306, 768). The two types of rings occur in different regions of the spirals, which can be explained on the basis of the tidal hypothesis by extending the previous research work of Chatterjee (1984, Ap&SS, 106, 309). In this context, using the same theory, we study many normal on-axis collisions (as rings are best formed for this orientation) between a disk galaxy, modeled as an exponential disk with a polytropic n = 0,3,4, bulge (mass being equally distributed amongst the polytropic indices), and a compact spherical intruder, modeled with a polytropic n = 2, 3, 4, distribution (mass being equally distributed amongst the polytropic indices). The internal energy changes suffered by the disk, have a direct bearing on the sharpness of the rings, and are directly obtained from the relationship, for the fractional change in internal energy of the disk, as fE = γβ, where β is a function of the galactic models and the collision parameter γ = G(σs/V2) ∝ σs/V2 (where σs is the projected velocity of collision). We find that sharp rings form for fE ≥ 0.5; beyond this value of fE the intensity contrast of the rings diminish. However, fairly sharp rings (from an observational point of view) form for fE ≥ 1/3, which corresponds to 7 ≥ 0.01; which corresponds to a density maximum near a region ~ (1/3)R (R being the radius of the disk galaxy), so that rings of tidal origin are not expected to be prominent at a distance interior to ~ 1/3 of the radius of the disk galaxy. They are not expected to form interior to ~ 1/10 of the radius of the disk.
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Vyas, Kunj N., and Mehul I. Solanki. "Penile strangulation by a metal ring: an easy and unique thread method for removal of the ring." International Surgery Journal 6, no. 2 (January 28, 2019): 623. http://dx.doi.org/10.18203/2349-2902.isj20190418.
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Penile incarceration is a rare but serious problem. Rapid treatment is necessary to prevent penile infarction. Glass bottles, metal rings, steel nuts and bull rings have been reported as constricting agents. Depending on the type of material, various tools such as diamond drills, bolt cutters and glass saws have been used to remove the objects. Penile strangulation by metal ring is a rare surgical emergency situation which requires urgent intervention to avoid vascular and urethral injury. It is usually associated with an attempt to improve sexual act and/or to prolong erection, psychosexual disorder. It is difficult to cut a metal ring as the edema was out of proportion and metal ring had made pressure ulcer at pen scrotal junction. The treatment of penile strangulation is decompression of the constricted penis to facilitate free blood flow and micturition. It requires no particular skill but does require resourcefulness to perform the removal simply and effectively, and with as little discomfort for the patient as possible. Here, author presented a case of penile strangulation in which metal ring was removed by silk thread.
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Ghouili, Afef, Ameni Brahmia, and Rached Ben Hassen. "Polymorphism in 3-acetyl-4-hydroxy-2H-chromen-2-one." Acta Crystallographica Section C Structural Chemistry 71, no. 10 (September 18, 2015): 873–77. http://dx.doi.org/10.1107/s2053229615016083.
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A new polymorph (denoted polymorph II) of 3-acetyl-4-hydroxy-2H-chromen-2-one, C11H8O4, was obtained unexpectedly during an attempt to recrystallize the compound from salt–melted ice, and the structure is compared with that of the original polymorph (denoted polymorph I) [Lyssenko & Antipin (2001).Russ. Chem. Bull.50, 418–431]. Strong intramolecular O—H...O hydrogen bonds are observed equally in the two polymorphs [O...O = 2.4263 (13) Å in polymorph II and 2.442 (1) Å in polymorph I], with a slight delocalization of the hydroxy H atom towards the ketonic O atom in polymorph II [H...O = 1.32 (2) Å in polymorph II and 1.45 (3) Å in polymorph I]. In both crystal structures, the packing of the molecules is dominated and stabilized by weak intermolecular C—H...O hydrogen bonds. Additional π–π stacking interactions between the keto–enol hydrogen-bonded rings stabilize polymorph I [the centres are separated by 3.28 (1) Å], while polymorph II is stabilized by interactions between α-pyrone rings, which are parallel to one another and separated by 3.670 (5) Å.
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Ostapski, W., T. Wierzchoń, J. Rudnicki, and S. Dowkontt. "Erratum to: Simulation and bench studies of the constructively and technologically modernized high performance piston aircraft engine. Stage I." Bulletin of the Polish Academy of Sciences Technical Sciences 65, no. 2 (April 1, 2017): 273–75. http://dx.doi.org/10.1515/bpasts-2017-0031.
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Abstract In Ostapski et al., Bull. Pol. Ac.: Tech 65(1), 93-105 (2017), doi: 10.1515/bpasts-2017-0012, an analysis of tribological wear of an assembly composed of cylinder liner and piston rings in a piston aircraft engine was presented. In place of the previously used technology of gas nitriding of the cylinder liner (made out of 38CrAlMo6-10 steel), formation of multi-component or composite layers by nitriding in plasma discharge environment was proposed. Also, a modification of the previously used chromium coating of the piston rings by plasma nitriding was proposed. A study on the structure and properties of surface layer diffusion manufactured by utilizing the phenomenon of cathode sputtering was carried out. Wear resistance tests were performed on a specially designed bench, with the use of isotope markers. Verification of each of the friction couples was based on using the wear of the ring as a function of the distance trip, and the roughness of the cylinder liner and ring. This note corrects flaws in illustrations published in the original paper.
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Horrell, I., P. A’Ness, S. A. Edwards, and I. Riddoch. "Nose-rings influence feeding efficiency in pigs." Animal Science 71, no. 2 (October 2000): 259–64. http://dx.doi.org/10.1017/s1357729800055090.
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AbstractNose-rings are often fitted to outdoor commercial pigs to inhibit rooting and reduce consequent pasture damage. During ethological observations of the behaviour of ringed pigs at pasture, subjective impressions suggested that pigs with nose-rings picked up their normal feed, in the form of large nuts (‘roll nuts’), more tentatively than unringed pigs. The observed pigs were gestating sows under one of three treatments: unringed controls (UR), multiple wire ‘clip-rings’ through the upper rim of the snout (CR), or rigid ‘bull-rings’ through the nasal septum (BR). For formal assessment of feeding efficiency eight randomly selected pigs from each condition were timed and video-recorded, in individual feeder stalls, as they ate 20 3-cm long roll-nuts laid out in a standard rectilinear array in a steel-sided tray under each of five conditions: on a hard surface, on the surface of soil, on the surface of turf, embedded in soil, or embedded in turf. All groups took longer to eat up their test meal from the plain surface than from the surfaces of either soil or turf and longer still when the nuts were embedded. In all conditions, ringed pigs took longer to eat their 20 nuts than did controls, with BR > CR > UR (overall mean times, pooling data from the different feeding conditions: 118·6, 69·9 and 56·7 s respectively: P < 0·001). The difference between groups was greatest when nuts were embedded. Also, when nuts were embedded, ringed pigs were more reluctant to root: the latency to their first rooting action was delayed (mean latency across both embedded’ conditions: 29·6, 87·9 and 106·8 s for UR, CR and BR pigs, respectively: P < 0·01 with soil and turf conditions combined) and, even after starting, a smaller proportion of the residual trial time was spent rooting (0·11, 0·27 and 0·62 of the total time by BR, CR and UR pigs respectively; P < 0·001). It is concluded that nose-ringing depresses the efficiency with which pigs feed on solid food, especially if they have to root for it. The threat to welfare inherent in this will be greatest when ringed pigs are in direct competition with unringed pigs.
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Stewart, Kirsty. "Redetermination ofL-tryptophan hydrobromide." Acta Crystallographica Section E Structure Reports Online 65, no. 6 (May 14, 2009): o1291—o1292. http://dx.doi.org/10.1107/s1600536809017322.
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The redetermined crystal structure of the title compound, C11H13N2O2+·Br−, is reported. Data collection at 100 K about three crystallographic axes resulted in a crystal structure with significantly higher precision in comparison to the two-dimensional data collected at 176 K [Takigawaet al.[(1966)Bull. Chem. Soc. Jpn,39, 2369–2378]. The carboxyl group and indole ring system are planar, with maximum deviations of 0.002 (2) and 0.007 (2) Å, respectively, and make an angle of 70.17 (1)° with each other. The molecules are arranged in double layers of carboxyl and amino groups parallel to theabplane, stabilized by an extensive network of N—H...Br and O—H...Br hydrogen bonds. The polar layer is held together by a network of three N—H...Br hydrogen bonds and one O—H...Br hydrogen bond. In the non-polar layer, the indole rings are linked mainly by electrostatic N—H...C interactions between the polarized bond N—H (H is δ+) of the pyrrole unit and two of the ring C atoms (δ−) of the benzene rings of adjacent molecules. The distances of these electrostatic interactions are 2.57 and 2.68 Å, respectively. C—H...O and C—H...π interactions are also present.
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Edwards, S. A., E. Anssems, R. I. Horrell, P. A. Ness, and J. Eddison. "The effect of nose ringing of outdoor sows on foraging behaviour and pasture damage." Proceedings of the British Society of Animal Science 1996 (March 1996): 194. http://dx.doi.org/10.1017/s1752756200593867.
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Nose ringing of outdoor sows is widely practiced to reduce pasture damage, but may have both short and longer term implications for animal welfare. This study was carried out to assess the effectiveness of different forms of nose ring and the extent of behavioural modification which they caused.Six groups of 5 sows were allocated between three treatments: unrung (U), rung with three traditional boss-rings through the upper rim of the nasal disc (TR) or rung with a single bull-ring through the nasal septum (BR). Groups were placed in adjacent paddocks on undamaged grass leys at a stocking rate of 38 sows/ha. Pasture damage was assessed weekly by measuring proportions of grass, bare earth and overturned earth in 20 half-metre square quadrats per paddock on a fixed sampling pattern.
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Edwards, S. A., E. Anssems, R. I. Horrell, P. A. Ness, and J. Eddison. "The effect of nose ringing of outdoor sows on foraging behaviour and pasture damage." Proceedings of the British Society of Animal Science 1996 (March 1996): 194. http://dx.doi.org/10.1017/s0308229600031573.
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Nose ringing of outdoor sows is widely practiced to reduce pasture damage, but may have both short and longer term implications for animal welfare. This study was carried out to assess the effectiveness of different forms of nose ring and the extent of behavioural modification which they caused.Six groups of 5 sows were allocated between three treatments: unrung (U), rung with three traditional boss-rings through the upper rim of the nasal disc (TR) or rung with a single bull-ring through the nasal septum (BR). Groups were placed in adjacent paddocks on undamaged grass leys at a stocking rate of 38 sows/ha. Pasture damage was assessed weekly by measuring proportions of grass, bare earth and overturned earth in 20 half-metre square quadrats per paddock on a fixed sampling pattern.
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Airoldi, Annalisa, Piergiorgio Bettoni, Monica Donnola, Gianluca Calestani, and Corrado Rizzoli. "Crystal structure of zwitterionic 3-(2-hydroxy-2-phosphonato-2-phosphonoethyl)imidazo[1,2-a]pyridin-1-ium monohydrate (minodronic acid monohydrate): a redetermination." Acta Crystallographica Section E Crystallographic Communications 71, no. 1 (January 1, 2015): 51–54. http://dx.doi.org/10.1107/s2056989014026863.
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In a previous study, the X-ray structure of the title compound, C9H12N2O7P2·H2O, was reported [Takeuchiet al., (1998).Chem. Pharm. Bull.46, 1703–1709], but neither atomic coordinates nor details of the geometry were published. The structure has been redetermined with high precision as its detailed knowledge is essential to elucidate the presumed polymorphism of minodronic acid monohydrate at room temperature. The molecule crystallizes in a zwitterionic form with cationic imidazolium[1,2a]pyridine and anionic phosphonate groups. The dihedral angle formed by the planes of the pyridine and imidazole rings is 3.55 (9)°. A short intramolecular C—H...O contact is present. In the crystal, molecules are linked by O—H...O, N—H...O and C—H...O hydrogen bonds and π–π interactions [centroid-to-centroid distance = 3.5822 (11) Å], forming a three-dimensional structure.
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Horrell, RI, P. J. A'Ness, S. A. Edwards, and J. C. Eddison. "The Use of Nose-Rings in Pigs: Consequences for Rooting, Other Functional Activities, and Welfare." Animal Welfare 10, no. 1 (February 2001): 3–22. http://dx.doi.org/10.1017/s0962728600023228.
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AbstractCommercial pigs kept outdoors are often given nose-rings, to inhibit rooting and minimize pasture damage. If rooting is a ‘behavioural need’ in the pig, and ringing is effective because it renders rooting painful, nose-ringing may be a threat to welfare. Thirty gestating sows were assigned to one of three conditions: unringed controls (UR); sows ringed with three, wire ‘clip’ rings through the snout rim (CR); or sows with one, rigid ‘bull’ ring (BR). They were observed on grass for 7h day−1 at intervals over 6 months. Ringing almost totally abolished penetration of the ground by rooting during the month after ringing (UR, CR and BR sows respectively spent 5.6%, 0.1% and 0.1 % of scan observations dig-rooting during this month; P < 0.001). These differences in recorded rooting were reflected in a much greater extent of pasture damage in paddocks containing UR sows. Rooting remained largely suppressed throughout the 6 months of observations in BR sows; but substantial recovery of this function occurred in CR sows by the sixth month, although much of this may be attributed to the fact that most sows lost at least some of their rings. Ringing also partially inhibited grazing (which accounted for 26.2%, 27.1% and 21.9 % of scans over the whole project in UR, CR and BR sows respectively; P < 0.05), nosing in straw, digging out wallows and stone-chewing (18.3%, 9.5% and 9.2% respectively of all scans in UR, CR and BR sows; P < 0.001). Ringed sows spent more time standing but otherwise inactive than did controls (0.8%, 1.7% and 4.0% of all scans in UR, CR and BR sows respectively; P < 0 .001), and displayed more straw-chewing, vacuum-chewing and digging at soil with the forepaw. We conclude that nose-ringing in pigs inhibited a range of functional activities, as well as rooting, and elicited more behaviours that suggest a degree of reduced welfare. BR sows displayed more of these effects than did CR ones, although these differences may be largely, but not entirely, due to a loss of clip rings over time.
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A. Gosalia, Umang, Manish Srivastava, Neetu Yaduvanshi, Shivangi Jaiswal, Sonika Jain, Dharma Kishore, Jaya Dwivedi, and Swapnil Sharma. "One-pot mediated synthesis of pyrimidine and quinazoline annulated derivatives of nitrogen containing five membered rings through their nitrile derivatives as antibacterial agents." Bulletin of the Chemical Society of Ethiopia 37, no. 5 (June 30, 2023): 1193–208. http://dx.doi.org/10.4314/bcse.v37i5.12.
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ABSTRACT. Novel five-membered ring (pyrrole, pyrazole and imidazole)-based pyrimidine and quinazoline derivatives were synthesized by one-pot domino approach. This approach has the advantages of high yield, mild reaction conditions and a simple work-up procedure. The structure of the synthesized compound was elucidated by spectroscopy technique and elemental analysis. The synthesized compound were examined for antimicrobial activity against four bacteria (E. coli, S. pyogenes, S. aureus, and P. aeruginosa) and two fungi (C. albicans and A. clavatus) and most of the synthesized compound exhibited moderate to good activity against reference drug ampicillin, ciprofloxacin, norfloxacin, gentamycin, nystatin and griseofulvin, respectively.
KEY WORDS: One-pot, Pyrrole, Pyrazole, Imidazole, Pyrimidine, Quinazoline, Antimicrobial activity
Bull. Chem. Soc. Ethiop. 2023, 37(5), 1193-1208.
DOI: https://dx.doi.org/10.4314/bcse.v37i5.12
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E. Olalekan, Temitope, Eric O. Akintemi, Bernardus Van Brecht, and Gareth M. Watkins. "Synthesis, characterization and DFT studies of Schiff bases of p-methoxysalicylaldehyde." Bulletin of the Chemical Society of Ethiopia 37, no. 3 (March 6, 2023): 675–88. http://dx.doi.org/10.4314/bcse.v37i3.11.
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ABSTRACT. Five new Schiff bases synthesized by the reaction between 2-(methylthio)aniline derivatives and p-methoxysalicylaldehyde are presented as MtH-1 (R = H), MtH-2 (R = CH3), MtH-3 (R = OCH3), MtH-4 (R = Cl) and MtH-5 (R = Br). They were characterized by CHNS analyses, NMR (1H, 13C, DEPT135, COSY and HSQC), FTIR and UV-Vis spectroscopic techniques. FT-IR, elemental analyses and NMR data supported the formation of the Schiff bases, with the chemical shifts of azomethine and phenol protons showing sensitivity to ring substitution. The crystal structure of MtH-1 featured the alignment of the phenyl rings to each other and to the C=N group with dihedral angles >170o. The DFT calculations corroborated the bond lengths and angles of MtH-1. The HOMO-LUMO energies, dipole moments and other reactivity parameters were calculated. The methyl-substituted MtH-2 was the least polar of the compounds. With calculated energy band gaps of almost 4 eV, the compounds may have applications in the semiconductors field.
KEY WORDS: Schiff bases, p-methoxysalicylaldehyde, Crystal structure, Spectroscopic properties, DFT calculations
Bull. Chem. Soc. Ethiop. 2023, 37(3), 675-688.
DOI: https://dx.doi.org/10.4314/bcse.v37i3.11
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Taha Saad, Suad. "Co(II) and Ni(II) complexes with bis(4-((E)-(4,5-diphenyl-1H-imidazol-2-yl)diazenyl) phenyl)methane: synthesis, characterization and anti-corrosion effect investigation." Bulletin of the Chemical Society of Ethiopia 38, no. 4 (April 30, 2024): 963–71. http://dx.doi.org/10.4314/bcse.v38i4.12.
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Bright coloured Co (II) and Ni (II) complexes of an azo ligand were synthesized. This ligand was previously synthesized from the coupling reaction between 4,5-diphenyl imidazole and 4,4-diaminodiphenylmethane in 1:2 molar ratio (4,4-diaminodiphenylmethane and 4,5-diphenyl imidazole). The synthesis process of the complexes involved the reflux reaction between the azo ligand with both metal salts. The synthesized complexes were characterized by FTIR, UV.-Visible, molar conductivity and atomic absorption. From the obtained characteristic data of the FTIR spectra, the coordination between the two metals and the azo ligand occurs by the coordination with the nitrogen atom of the azo group and one of the nitrogen atoms in the imidazole both rings. The molar conductivity test confirm the non- electrolytic nature of both complexes, while the atomic absorption agrees with the expected complexes formula. Therefore, the octahedral structure for the two complexes is suggested. The anti-corrosion activity of the synthesized compounds were investigated under two temperatures (298 and 308 K) with 0.03 gm of each compound was tested. According to the results cobalt (II) complex shows a better anti-corrosion activity (93%) in comparison with the ligand and nickel (II) complex. KEY WORDS: Cobalt(II) and nickel(II) azo complexes, Imidazole derivative, Anti-corrosion effect Bull. Chem. Soc. Ethiop. 2024, 38(4), 963-971. DOI: https://dx.doi.org/10.4314/bcse.v38i4.12
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Subbaiah, K. Venkata, D. V. R. Sai Gopal, and M. Krishna Reddy. "First Report of a Tospovirus on Sunflower (Helianthus annus L.) from India." Plant Disease 84, no. 12 (December 2000): 1343. http://dx.doi.org/10.1094/pdis.2000.84.12.1343b.
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Virus-like symptoms were observed on sunflower in and around Tirupati during January 1998. Infected plants exhibited severe mosaic, systemic necrosis along the stem and floral heads, leaf distortion, and ringspots on leaves. The causal virus, mechanically transmissible from sunflower to sunflower cvs. Morden, MHSF8, MHSF18, KBHS1, and Cargil, developed symptoms like those in the original plant. The virus caused chlorotic and necrotic spots on Chenopodium amaranticolor, chlorotic and necrotic rings on cowpea cv. C-152, chlorotic spots on Datura metal and Petunia hybrida, chlorotic rings and systemic infection on Gomphrena globosa, tarlike symptoms on Catharanthus roseus, and local brown lesions on Cassia tora (1). Virus was isolated from infected sunflower leaves (2), and particles in negatively stained preparations were enveloped and 80 to 90 nm in diameter. Cytopathic effects included accumulation of virus particles in the endoplasmic reticulum, the formation of viroplasm, and aggregates consisting of nonenveloped viral nucleocapsids in the cytoplasm of ultrathin sections of infected sunflower leaves. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of capsid protein resolved as a single band of 31 kD. The dsRNA isolated from infected sunflower leaves resolved as three bands of 9, 4.9, and 3 kb in 2% agarose gel electrophoresis. In enzyme-linked immunosorbent assay, the purified virus reacted with homologous and Peanut bud necrosis virus (PBNV-ICRISAT, India) antisera and not to polyclonal antibodies to Iris yellow spot virus (Netherlands), Tomato spotted wilt virus-T (Georgia), Impatiens necrotic spot virus, and several isolates of Cucumber mosaic virus (CMV-B, CMV-C, CMV-To). In western blotting analysis, the virus coat protein reacted with homologous and PBNV antisera corresponding to coat protein band of 31 kD. In reverse transcription polymerase chain reaction, the viral RNA was amplified by using primers derived from NP gene sequence of PBNV and Watermelon silver mottle virus (WSMV). Based on these properties, the virus causing sunflower mosaic followed by necrosis in India was identified as a tospovirus, which may be as a distinct isolate of sero group IV. References: (1) A. A. Brunt et al. Viruses of Plants Online. 1996. Australian National University, Canberra, 1996. (2) D. V. R. Reddy et al. Bud necrosis virus: A disease of peanut caused by Tomato spotted wilt virus. ICRISAT Inf. Bull. No. 31, 1991.
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Bilousova, A. A., N. V. Cherevach, O. A. Dregval, L. P. Golodok, and T. V. Sklyar. "Sanitary and Microbiological Research of Fish Products Sold in Dnipro city." Ukraïnsʹkij žurnal medicini, bìologìï ta sportu 5, no. 6 (December 12, 2020): 336–41. http://dx.doi.org/10.26693/jmbs05.06.336.
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Fish is a valuable food product that has a high biological value, but spoils quickly because its muscle tissue contains a lot of moisture and can be contaminated with microflora through the intestines, mucus of the skin and gills. Insufficiently fresh fish can cause serious diseases: toxicoinfections and toxicosis, intestinal infectious diseases caused by Shigella, Salmonella, Escherichia coli, Proteus, Clostridia, various coccal microflora. The urgency of this problem encourages the study of sanitary-indicative microorganisms of fish and seafood to prevent foodborne infections. The purpose of the work was to study the microbial contamination of ready-to-eat fish and seafood sold in the retail chains of the city of Dnipro, to determine the compliance of product quality with sanitary requirements. Material and methods. 53 samples of fish and seafood of different brands were analyzed: 23 samples of low-salt products, among which were preserves from fish "Herring", preserves from mussels, salted low-salt and 30 dried products: dried squid, dried squid rings and dried bull. The number of mesophilic aerobic and facultative anaerobic microorganisms, Escherichia coli bacteria, the presence of coccal microflora, mold and anaerobes were determined in each of the samples. Results and discussion. The results of the sanitary-microbiological study showed that 43.4% of the analyzed samples (23 samples) did not meet the normative indicators. The largest deviations from the norm were found in the content of mesophilic aerobic and facultative anaerobic microorganisms and Escherichia coli bacteria. The study showed that in 39.6% of samples the number of mesophilic aerobic and facultative anaerobic microorganisms was exceeded, and in 32.0% - the number of Escherichia coli bacteria. Most contaminated products were found among the samples of dried squid – 50% of samples, preserves from fish "Herring" – 36.4% and preserves from mussels – 36.4%, dried squid rings – 33.3%. It was found that 18.8% of samples of fish and fish products contained Staphylococcus aureus, 7.5% of samples – sulfate-reducing clostridia. Conclusion. The obtained results indicated the non-compliance of a large number of fish and seafood with the normative indicators. This may be due to the condition of the reservoirs in which the catch was made, improper processing of raw materials, non-compliance with storage conditions, transportation of the product. Therefore, it is important to further improve the quality of fish products by controlling raw materials, compliance of production technology with international and national standards. The solution of this problem is possible under the condition of state involvement in the process of quality control of fish products on the market of Ukraine. The results of research can be used to monitor the quality of fish and seafood sold in retail chains
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Haider, Rehan. "Wilson's Disease." Cancer Research and Cellular Therapeutics 7, no. 3 (July 24, 2023): 01–08. http://dx.doi.org/10.31579/2640-1053/149.
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In 1912, Kinnear Wilson was the first to describe an inherited fatal disease associated with progressive lenticular degeneration, chronic liver disease and cirrhosis (Wilson 1912) [1]. In the same year, Kayser and Fleischer found that patients with Wilson's disease (WD) often had brownish deposits of copper on the cornea, now called Kayser-Fleischer rings (Fleischer 1912) [2]. WD is an autosomal recessive metabolic disorder. Its ATP7B gene encodes a copper-transporting ATPase (Bull 1993, Tanzi 1993, Petrukhin 1993, Yamaguchi 1993) [3,4,5,6]. A genetic defect in the ATP7B protein reduces Biliary excretion of copper leads to accumulation of copper in the cornea and various organs, including the liver, brain, and kidneys. Alteration of the ATP7B protein also reduces copper incorporation into ceruloplasmin. The corresponding presence of ceruloplasmin APO (ceruloplasmin without copper incorporation) results in decreased circulating levels of ceruloplasmin due to the shortened half-life of the APO protein. Thus, despite the accumulation of copper in many organs, circulating levels of copper and ceruloplasmin are reduced in most patients with WD. The prevalence of WD is rare, estimated at 3 per 100,000 in the general population (Friedman 1990) [7]. The clinical picture may vary. Some patients with WD are diagnosed with liver problems, while others have neurological or psychiatric symptoms; many patients show both liver and neurologic disease (Figure 1). Episodes of hemolysis and renal abnormalities may also occur. WD typically affects children and younger. Adults and is rarely seen in adults over 40 years of age. WD is fatal if not treated appropriately. Medications to treat WD are copper chelators. such as penicillamine and trientine (Walshe 1956) [8]. Lately, zinc has been. it is used to reduce the intestinal absorption of copper and to detoxify free circulating copper. Patients with fulminant liver failure or decompensated cirrhosis. may need a liver transplant (LTX) to cure WD.
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Sharma, M., R. Ghosh, U. N. Mangla, K. B. Saxena, and S. Pande. "Alternaria tenuissima Causing Alternaria Blight on Pigeonpea in India." Plant Disease 96, no. 6 (June 2012): 907. http://dx.doi.org/10.1094/pdis-01-12-0060-pdn.
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Pigeonpea (Cajanus cajan (L.) Millsp.) is a major grain legume of the tropics and subtropics worldwide. In India, pigeonpea is the third most important food legume after chickpea and field pea. Blight symptoms on pigeonpea were observed in alarming proportion during the 2009 through 2011 crop seasons in Andhra Pradesh state in India. Disease incidence ranged from 20 to 80% irrespective of cultivars sown. Infected plants in the field showed symptoms on all aerial parts of the plant (leaves, stems, buds, and pods) irrespective of age of the plant and leaves. Symptoms on leaves were small, circular, necrotic spots that developed quickly forming typical concentric rings (1). Later, these spots coalesced and caused blighting of leaves. Spots were initially light brown and later turned dark brown. On stems, spots were sunken with concentric rings. In severe infection, defoliation and drying of infected leaves, branches, and flower buds was observed. The fungus was successfully isolated from all the infected plant parts (leaves, stem, buds, and pods) on potato dextrose agar (PDA) medium. After 4 to 5 days of incubation at 28 ± 1°C with a 12-h photoperiod, the fungus produced colonies that were regular and flat. The periphery of the colony was olive green with a black center. Monoconidial isolations were used to establish a pure culture of the fungus. Conidiophores were short, arising singly, and were 8.86 mm long and 2.97 mm thick. Conidia varied from 15.78 to 28.70 mm long and 8.03 to 13.47 mm wide. Very small beak (1.6 to 3.2 mm) or no beak was observed. Horizontal and vertical septations of conidia varied from four to six and two to four, respectively. The pathogenicity test was conducted on 8- to 10-day-old pigeonpea plants of cultivar ICPL 87119 by spraying with a conidial suspension (5 × 105 conidia/ml). Inoculated plants were covered with polythene bags and kept in a greenhouse at 28 ± 1°C with a 12-h photoperiod. After 48 h, the polythene bags were removed. Ten days after inoculation, symptoms were similar to those observed in fields. This experiment was conducted twice with two independent sets of plants. No symptoms were observed in water-inoculated control plants. The fungus was reisolated from the inoculated plants. On the basis of the morphological characteristics, the pathogen was tentatively identified as Alternaria tenuissima. The identification was further confirmed by the rDNA and internal transcribed spacer (ITS) primer. The ITS region of rDNA was amplified with ITS 1 and ITS 4 primers. Both orientation sequenced amplicons (481 bp) were submitted to GenBank (Accession No. JQ074094). A BLASTn search revealed 99% similarity to A. tenuissima (Accession No. HQ343444). To our knowledge, this is the first report of molecular identification of A. tenuissima causing Alternaria blight in pigeonpea in India. Reference: (1) Kannaiyan, J. and Nene, Y. L. 1977. Trop. Grain Legume Bull. 9:34.
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Yamada, Hiroko, and Hironobu Hayashi. "(Invited) On-Surface Synthesis of Higher Acenes Using Precursors." ECS Meeting Abstracts MA2022-01, no. 10 (July 7, 2022): 793. http://dx.doi.org/10.1149/ma2022-0110793mtgabs.
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Acenes are polycyclic aromatic hydrocarbons made up of linearly fused benzene rings. They are the smallest units of graphene and graphene nanoribbons, and have been extensively studied as organic semiconductor materials. Higher acenes are expected to have smaller band gaps required for practical use as organic electronic materials, but those with more than six benzene rings are poorly soluble in common organic solvents and unstable in aerobic condition to be synthesized and purified with traditional organic synthesis method. To overcome the obstacles, a precursor approach is a useful technique, where the soluble and stable precursors are purified enough and then converted to less-soluble and unstable target acenes in-situ.[1,2] Recently surface-assisted synthesis of higher acenes using precursors have attracted much attentions. Under ultra-high vacuum atmosphere, unstable acenes can be prepared from precursors by annealing, photoirradiation, or scanning tunneling microscopy (STM)-tip treatment on metal surface. We were successful to synthesize bis-diketone precursors of heptacene and nonacene. [3-6] The precursors were vacuum-deposited on Au(111) surface and converted to heptacene and nonacene by photoirradiation. Through combined STM, non-contact atomic force microscopy(nc-AFM) and scanning tunneling spectroscopy (STS) measurements, together with state-of-the-art first principles calculations, insight into the chemical and electronic structure of these elusive compounds was successful. It was revealed that nonacene has open-shell biradical structure in the ground state on Au(111). We were also successful to prepare tetraazaundecacene on Au(111) surface from bicyclo[2.2.2]octadiene (BCOD) precursor. [7] The tip-induced release of the protecting group can be employed to produce the targeted tetraazaundecacene species. The experimental frontier orbital gap, derived from the difference between PIR and NIR, is 1.35 eV. In this talk, the attraction and possibility of the “precursor approach” for the synthesis and application of acene compounds will be overviewed. References M. Suzuki, T. Aotake, Y. Yamaguchi, N. Noguchi, H. Nakano, K. Nakayama, H. Yamada, J. Photochem. Photobiol. C: Photochem. Rev. 2014, 18, 50-70. H. Yamada, D. Kuzuhara, M. Suzuki, H. Hayashi, N. Aratani, Bull. Chem. Soc. Jpn. 2020, 93, 1234-1267. J. I. Urgel, S. Mishra, H. Hayashi, J. Wilhelm, C. A. Pignedoli, M. Di Giovannantonio, R. Widmer, M. Yamashita, N. Hieda, P. Ruffieux, H. Yamada, R. Fasel, Nat. Commun. 2019, 10, 861–864. J. I. Urgel, H. Hayashi, M. Di Giovannantonio, C. A. Pignedoli, S. Mishra, O. Deniz, M. Yamashita, T. Dienel, P. Ruffieux, H. Yamada, R. Fasel, J. Am. Chem. Soc. 2017, 139, 11658–11661. J. I. Urgel, M. Di Giovannantonio, G. Gandus, Q. Chen, X. Liu, H. Hayashi, P. Ruffieux, S. Decurtins, A. Narita, D. Passerone, H. Yamada, S.-X. Liu, K. Müllen, C. A. Pignedoli, R. Fasel, ChemPhysChem 2019, 20, 2360-2366. C. G. Ayani, M. Pisarra, J. I. Urgel, J. J. Navarro, C. Díaz, H. Hayashi, H. Yamada, F. Calleja, R. Miranda, R. Fasel, F. Martín, A. L. Vázquez de Parga, Nanoscale Horiz. 2021, 6, 744-750. K. Eimre, J. I. Urgel, H. Hayashi, M. D. Giovannantonio, P. Ruffieux, S. Sato, S. Ohtomo, Y. S. Chan, N. Aratani, D. Passerone, O. Gröning, H. Yamada, R. Fasel, C. A. Pignedoli, Nat. Commun. 2021. in press.
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Савельєв, О. К., О. П. Сєкерська, and О. О. Грицюта. "Оброблена кістка та ріг із Тіри-Білгорода римського та ранньомодерного часу (матеріали розкопок 2020—2021 рр.)." Arheologia, no. 4 (December 5, 2023): 90–101. http://dx.doi.org/10.15407/arheologia2023.04.090.
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In 2020—2021, during excavations in the Civil Courtyard of the Akkerman Fortress, a collection of 26 bone items was collected, which are being published in the following article. The objects come from the layers and complexes mainly of the Modern (16th — 18th centuries) and Roman times and according to their functional purpose belong to several categories. The household items and the items for games (buckle fragments of knife handles, hookah mouthpieces, gambling or divination astragals, and a button), weapon products (rings for pulling back the bowstring), and work tools, facing plates, blanks and production waste are singled out. Items made of bone and horns are one of the main categories of material for the reconstruction of various aspects of the economy, everyday life and spiritual life of the ancient population. The analysed bone and horn objects are a small part of the collection of bone artefacts from the Tyras-Bilhorod excavations of the antique and modern periods, but they provide insight into the production of specialised crafts and manufacturing of bone products in individual households. Despite the small number of finds, the collection includes such categories of material as raw materials, blanks, production waste and finished items, which is one of the signs of the bone-cutting production presence directly on the territory of the city. Characterising the raw material base of the bone-cutting production, we should point out that the material for manufacturing was bones and horns of animals that were bred or obtained by the inhabitants of the city — a horse, a domestic bull, a sheep, a European deer and roe deer, as well as bone rays of the pectoral fins of sturgeon. During production, the peculiarities of the structure of bone raw materials were taken into account, which made it possible to use the shape of the bone/horn the best possible way to manufacture a specific object/tool. Certain types of bone objects existed in a rather wide chronological range (astragals for the game, plates — covers of knife handles etc.) The obtained results are important for the reconstruction of the bone-cutting and complement the existing ideas about the daily life of the inhabitants of Tyras-Bilhorod in the Roman and Modern times.
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Marques, Ricardo, Lukas Jelinek, Manuel J. Freire, Juan Domingo Baena, and Mikhail Lapine. "Bulk Metamaterials Made of Resonant Rings." Proceedings of the IEEE 99, no. 10 (October 2011): 1660–68. http://dx.doi.org/10.1109/jproc.2011.2141970.
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Hlushkova, Diana, and Valeriy Bagrov. "Research of surface layer properties of piston rings after gas thermal spraying." Bulletin of Kharkov National Automobile and Highway University, no. 94 (December 16, 2021): 18. http://dx.doi.org/10.30977/bul.2219-5548.2021.94.0.18.
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Today, one of the important problems of mechanical engineering is to increase the reliability and durability of machines. A special place in this matter is occupied by increasing the wear resistance of parts. As for diesel construction, the problem of increasing the hardness and wear resistance of piston rings is very important. Goal. The goal is study of the structure and nature of changes in the hardness of the surface layer obtained by gas-thermal combined spraying, after grinding, running-in and mileage of the diesel engine, i. e., at all stages of the production cycle. Methodology. The coating on the rings was applied by the method of two-wire metallization with independent supply of wires made of 11X18M steel and molybdenum. Metallographic analysis was used to study the structure of the obtained coating. The condition of the surface layer after coating, grinding, running-in and diesel run was studied by measuring the microhardness. Results. Metallographic analysis of the interface between steel and molybdenum coating – cast iron for many rings and different parts of one ring shows that the coating interacts closely with the substrate along the entire application profile. The structure of molybdenum particles demonstrates their fineness. This is due to the fact that the rapid crystallization under pressure contributes to the creation of a fine-grained structure. Comparison of the microhardness of molybdenum and steel wires with steel-molybdenum coating indicates a significant strengthening of molybdenum and steel particles during spraying, due to the processes of structure formation. Experimental data indicate the stability of the hardness of both molybdenum particles and steel particles, which is important for the coating in operation. Originality. Features of formation of a gas-thermal covering at a simultaneous electric arc spraying of molybdenum and 11Х18М steel on piston rings from pig-iron are established. It is shown that a layered structure is formed, which consists mainly of steel and molybdenum particles. The reasons for the wide range of properties of steel and molybdenum particles have been clarified. It is proved that the operational properties of steel-molybdenum coating are due to its antifriction properties, porosity, which provides self-lubrication of the friction surface, good adhesion to the substrate, which increases by 3–4 times compared to traditional methods. Practical value. The proposed technology of gas-thermal spraying significantly increases the service life of piston rings operating in wear conditions.
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Hlushkova, D. B., and A. I. Stepanyuk. "TREATMENT OF PISTON RINGS WITH HIGH ENERGY SOURCES." Bulletin of Kharkov National Automobile and Highway University, no. 82 (December 23, 2018): 51. http://dx.doi.org/10.30977/bul.2219-5548.2018.82.0.51.
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Qureshi, A. Aziz, K. E. Lawande, Sibi Mani, and Vaishali B. Patil. "Colour and tissue differences in distribution of quercetin in Indian onions (Allium cepa)." Indian Journal of Agricultural Sciences 82, no. 7 (July 11, 2012): 629–31. http://dx.doi.org/10.56093/ijas.v82i7.21688.
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The above investigation revealed that quercetin content varied spatially in the bulb portions as well as in the rings of short-day Indian onions. It was high in top portion of bulb or in the outer rings. Dark coloured bulbs had greater amounts of quercetin in comparison to white bulbs. These findings would provide essential information for majority of people in India, South Asia and Gulf who consume onion in salads about the coloured bulbs that it contains more quercetin levels. Hence, consumption of coloured bulbs particularly the top portion or outer rings is more beneficial in meeting the dietary requirement of quercetin, which is an essential health compound.
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Hlushkova, Diana. "Study of the influence of vacuum-arc coating on the wear-resistance of piston rings." Bulletin of Kharkov National Automobile and Highway University, no. 94 (December 16, 2021): 59. http://dx.doi.org/10.30977/bul.2219-5548.2021.94.0.59.
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The effect of a multilayer vacuum-arc nanostructured Ti-Mo-N coating, its application parameters on the wear resistance of piston rings is studied. The effect of the parameters of vacuum-arc deposition on the nanohardness is established.
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Duchoslavová, J., I. Širučková, E. Zapletalová, M. Navrátil, and D. Šafářová. "First Report of Brown Rot Caused by Monilinia fructicola on Various Stone and Pome Fruits in the Czech Republic." Plant Disease 91, no. 7 (July 2007): 907. http://dx.doi.org/10.1094/pdis-91-7-0907b.
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Monilinia fructicola, a causal agent of brown rot, is one of the most important fungal pathogens of stone fruits. The disease causes major crop losses in peach, plum, prune, nectarine, and apricot. M. fructicola is commonly present in Asia, North and South America, and Australia. This is a quarantined pathogen in Europe; restricted occurrence has been observed in Austria and France. Recently, it was detected in Hungary and Switzerland on peach and nectarine fruits imported from Italy and Spain (1,4). During a survey in the summer of 2006, 56 samples were tested for the presence of Monilinia spp. M. fructicola was detected in 15 samples from 11 locations in the western area (Bohemia) of the Czech Republic, mainly on peaches (Prunus persica), apples (Malus × domestica), and sweet and sour cherries (Cerasus avium and C. vulgaris) and rarely on flowering plum (Prunus triloba) and Malus × moerlandsii cv. Liset. On the other hand, the pathogen was not detected on fruits of apricot (Prunus armeniaca) or pear (Pyrus communis). In all cases, M. fructicola was detected on fruits except for a single occurrence of the pathogen on a shoot of the Malus × domestica. The pathogen was always detected in mixed infections with M. fructigena and/or M. laxa. On both fruits and the shoot, symptoms appeared as brown, sunken lesions covered with grayish pustules. Many infected fruits became dry and mummified because rot progressed through the fruit surface. The infected shoot died back (3). M. fructicola was identified by means of colony and conidial morphology and molecular characteristics. The colonies cultivated on potato dextrose agar were entire and the colony surface was even. The color of the colony was gray, and sporulating colonies showed concentric rings that changed to a hazel color. Conidia were ellipsoid, hyaline, and 13.5 to 17.7 × 8.3 to 10.5 μm. Preliminary morphological identification was confirmed by PCR (2) on DNA isolated directly from mycelium on the examined fruits. A product that was 280 bp long was obtained in all cases. The BLAST analysis of our PCR product sequences showed 100% homology to sequences of M. fructicola (GenBank Accession Nos. DQ491506, AY2891185, Z73778, and AB125615). One sequence from our study was deposited in GenBank (Accession No. EF378628). To our knowledge, this is the first report of the quarantined fungus M. fructicola in the Czech Republic. References: (1) E. Bosshard et al. Plant Dis. 90:1554, 2006. (2) K. J. D. Hughes et al. EPPO Bull. 30:507, 2000. (3) J. M. Ogawa et al., eds. Compendium of Stone Fruit Diseases. The American Phytopathological Society, St. Paul, MN, 1995. (4) M. Petróczy and L. Palkovics. Plant Dis. 90:375, 2006.
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Hlushkova, D. "Laser processing for increasing the durability of the piston rings." Bulletin of Kharkov National Automobile and Highway University 1, no. 88 (October 9, 2020): 91. http://dx.doi.org/10.30977/bul.2219-5548.2020.88.1.91.
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Fidrovskay, Natalia, Sergey Hursenko, and Oleg Bobonec. "Substantiation of feasibility of installing rigidity rings in mine drums." Bulletin of Kharkov National Automobile and Highway University 2, no. 88 (December 18, 2020): 67. http://dx.doi.org/10.30977/bul.2219-5548.2020.88.2.67.
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Semkov, Krumm, Nikolai Kolev, and Vladimír Staněk. "Theoretical and experimental investigation of the function of the wall flow deflecting ring. The determination of the optimum distance between deflecting rings." Collection of Czechoslovak Chemical Communications 52, no. 10 (1987): 2438–46. http://dx.doi.org/10.1135/cccc19872438.
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Based on the earlier published mathematical model the problem has been solved of the optimum distance between the wall flow deflecting rings. These rings of small width placed near the wall of a packed column provide for the equality of the integral mean densities of irrigation in region near the column wall and in the bulk of the packing. An equation has been derived for the optimum distance between the wall flow deflecting rings convenient for practical calculations. A practical example has been used to show that the wall flow deflecting rings substantially improve the distribution of liquid in the column.
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Arsénio, António J., Francisco Ferreira da Silva, João F. P. Fernandes, and Paulo J. Costa Branco. "Optimization of the Guiding Stability of a Horizontal Axis HTS ZFC Radial Levitation Bearing." Actuators 10, no. 12 (November 26, 2021): 311. http://dx.doi.org/10.3390/act10120311.
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This document presents a study on the optimization of the 3D geometry of a horizontal axis radial levitation bearing with zero-field cooled (ZFC) high-temperature superconductor (HTS) bulks in the stator, and radially magnetized permanent magnet (PM) rings in the rotor. The optimization of component dimensions and spacing to minimize the volume or cost concerning only the maximization of the levitation force was previously studied. The guidance force and guiding stability depend on the spacing between PM rings in the rotor and between the rings of HTS bulks in the stator. This new optimization study aims to find the optimum spacing that maximize the guidance force with given HTS bulk and PM ring dimensions while maintaining the minimum required levitation force. Decisions are taken using the non-dominated sorting genetic algorithm (NSGA-II) over 3D finite element analysis (FEA). A simplified electromagnetic model of equivalent relative permeability is used on 3D FEA to reduce numerical processing and optimization time. Experimental prototypes were built to measure magnetic forces and validate appropriate values of equivalent magnetic permeability. An analysis of stable and unstable geometry domains depending on the spacing between rings of HTS bulks and PM rings is also done for two HTS bulk sizes.
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Hlushkova, D. B. "INCREASE OF LONGNESS OF PISTON RINGS METHOD OF TWO-WIRE METALIZATION." Bulletin of Kharkov National Automobile and Highway University, no. 82 (December 23, 2018): 27. http://dx.doi.org/10.30977/bul.2219-5548.2018.82.0.27.
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AL-badri, A. M. S. "Macroscopic study of syrinx in the common bulbul (Pycnontus barbatus) and indigenous pigeon (Columba domestica)." Al-Qadisiyah Journal of Veterinary Medicine Sciences 13, no. 1 (June 30, 2014): 88. http://dx.doi.org/10.29079/vol13iss1art284.
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In this study, syrinx of five male common bulbuls (Pycnontus barbatus) weighing (25.93 ±0.89 g) and five male indigenous pigeons (Columba domestica) weighing (286±0.73 g) were examined for macroscopic structure. The results showed the anatomical positions of the syrinx. The syrinx was observed ventral to the esophagus exactly on the base of heart in the common bulbul, whilst in pigeon; the syrinx was hidden by the heart. The morphological structure of the syrinx in both species could be classified as tracheobronchial type. The number of tracheo-syringeal rings could not be determined certainly in common bulbul, while in the pigeon, tracheo-syringeal part was composed of the two cartilaginous rings (T1 and T2). These two cartilaginous rings were different in diameters and joined each other at the middle. In the common bulbul, tympanum which is the middle part of syrinx has the bilateral bulla; while tympanum of pigeon does not have bulla. Furthermore, the broncho-syringeal cartilages from the caudal part of a syrinx, which is composed of five C-shaped rings in both species. The caudal syringeal part of common bulbul has intrabronchial foramen, which absents in a pigeon.
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Latorre, B. A., G. A. Díaz, A. L. Valencia, P. Naranjo, E. E. Ferrada, R. Torres, and J. P. Zoffoli. "First Report of Monilinia fructicola Causing Brown Rot on Stored Japanese Plum Fruit in Chile." Plant Disease 98, no. 1 (January 2014): 160. http://dx.doi.org/10.1094/pdis-06-13-0647-pdn.
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In autumn 2013, fruit of Japanese plum (Prunus salicina) cvs. Angelino and Black Kat developed an unusual brown and soft rot after 2 months in cold storage (0°C) on nearly 1% of the fruit. Fruit showed small, circular, light brown spots that eventually destroyed the entire fruit. Small sporodochia appeared on the fruit surface. Fruit was harvested from orchards located near San Francisco de Mostazal (33°59′ S, 70°41′ W), Chile. Small pieces of diseased tissue were selected from margins of lesions of surface disinfected (96% ethanol) fruit (n = 7) and placed on acidified potato dextrose agar (PDA) plates for 5 days at 20°C. Light brown colonies with even margins and concentric rings of spores were obtained. The conidia of five isolates were one-celled, hyaline, lemon-shaped, (min. 10.7) 14.9 ± 1.5 (max. 18.6) × (min. 8.1) 9.4 ± 0.8 (max. 10.8) μm (n = 30), and borne in branched monilioid chains. This fungus was identified as Monilinia fructicola (G. Winter) Honey (1). Identification was confirmed by amplifying and sequencing the ribosomal ITS1-5.8S-ITS2 region using ITS1 and ITS4 primers (3). BLAST analysis of Chilean plum isolates (GenBank Accession Nos. KF148610 and KF148611) were 99 to 100% identical to isolates of M. fructicola originating from the United States (DQ314727 and HQ846966, respectively) and 100% identical to the first Chilean isolate (JN001480) found in nectarines originating from California at the supermarkets in Santiago in June 2009. Koch's postulates were fulfilled by reproducing brown rot symptoms on mature wounded Japanese plums cv. Angelino (n = 8) inoculated with 10 μl of a conidial suspension (105 conidia/ml) or with a mycelium plug (5-mm diameter). After 2 days in humid chambers (>80% relative humidity) at 25°C, all inoculated fruit developed brown rot symptoms with necrotic lesion means of 15.8 and 21.5 mm in diameter in fruit inoculated with conidia and mycelium, respectively. Non-inoculated control fruit remained healthy. Re-isolations were performed on PDA and the presence of M. fructicola was morphologically confirmed in 100% of the symptomatic fruits. To our knowledge, this is the first report demonstrating the presence of M. fructicola causing brown rot in stored Japanese plums in Chile after its first interception in 2009 in Chile, suggesting that this pathogen has been established in the field. Currently, M. fructicola is a quarantine organism under official control, restricted to Prunus orchards between Santiago and Nancagua in central Chile (2). References: (1) EPPO. EPPO Bull. 39:337, 2009. (2) Servicio Agrícola y Ganadero, SAG, Ministerio de Agricultura, Gobierno de Chile. www.sag.cl , accessed 15 November 2013. (3) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, NY, 1990.
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Charalambous, M., R. Koch, A. D. Kent, and W. T. Masselink. "Hall magnetometry measurements of bulk single crystalline rings ofYBa2Cu3O7." Physical Review B 58, no. 14 (October 1, 1998): 9510–23. http://dx.doi.org/10.1103/physrevb.58.9510.
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Hsu, Hsiang-Wen, Jürgen Schmidt, Sascha Kempf, Frank Postberg, Georg Moragas-Klostermeyer, Martin Seiß, Holger Hoffmann, et al. "In situ collection of dust grains falling from Saturn’s rings into its atmosphere." Science 362, no. 6410 (October 4, 2018): eaat3185. http://dx.doi.org/10.1126/science.aat3185.
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Saturn’s main rings are composed of >95% water ice, and the nature of the remaining few percent has remained unclear. The Cassini spacecraft’s traversals between Saturn and its innermost D ring allowed its cosmic dust analyzer (CDA) to collect material released from the main rings and to characterize the ring material infall into Saturn. We report the direct in situ detection of material from Saturn’s dense rings by the CDA impact mass spectrometer. Most detected grains are a few tens of nanometers in size and dynamically associated with the previously inferred “ring rain.” Silicate and water-ice grains were identified, in proportions that vary with latitude. Silicate grains constitute up to 30% of infalling grains, a higher percentage than the bulk silicate content of the rings.
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KACHRU, SHAMIT. "QUANTUM RINGS AND RECURSION RELATIONS IN 2D QUANTUM GRAVITY." Modern Physics Letters A 07, no. 16 (May 30, 1992): 1419–25. http://dx.doi.org/10.1142/s0217732392001099.
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I study tachyon condensate perturbations to the action of the two-dimensional string theory corresponding to the c=1 matrix model. These are shown to deform the action of the ground ring on the tachyon modules, confirming a conjecture of Witten. The ground ring structure is used to derive recursion relations which relate (N+1) and N tachyon bulk scattering amplitudes. These recursion relations allow one to compute all bulk amplitudes.
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Costello, John H., Sean P. Colin, Brad J. Gemmell, and John O. Dabiri. "Hydrodynamics of Vortex Generation during Bell Contraction by the Hydromedusa Eutonina indicans (Romanes, 1876)." Biomimetics 4, no. 3 (July 5, 2019): 44. http://dx.doi.org/10.3390/biomimetics4030044.
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Swimming bell kinematics and hydrodynamic wake structures were documented during multiple pulsation cycles of a Eutonina indicans (Romanes, 1876) medusa swimming in a predominantly linear path. Bell contractions produced pairs of vortex rings with opposite rotational sense. Analyses of the momentum flux in these wake structures demonstrated that vortex dynamics related directly to variations in the medusa swimming speed. Furthermore, a bulk of the momentum flux in the wake was concentrated spatially at the interfaces between oppositely rotating vortices rings. Similar thrust-producing wake structures have been described in models of fish swimming, which posit vortex rings as vehicles for energy transport from locations of body bending to regions where interacting pairs of opposite-sign vortex rings accelerate the flow into linear propulsive jets. These findings support efforts toward soft robotic biomimetic propulsion.
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Zhong, Xin, Yanchao Wang, Feng Peng, Hanyu Liu, Hui Wang, and Yanming Ma. "Pressure stabilization of long-missing bare C6 hexagonal rings in binary sesquicarbides." Chem. Sci. 5, no. 10 (2014): 3936–40. http://dx.doi.org/10.1039/c4sc01383b.
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Schirarend, C. "Baas, P.; Vetter, R. E. (Eds.), Growth Rings in Tropical Trees. Proceedings of the joint session of IUFRO P 5.05 Tree Ring Analysis and IAWA on Aga and Growth Rate Determination in Tropical Trees, IAWA Bull. n. ser. 10 (2), S. 95-174, 120 Abb., 9 Tab. Lei." Feddes Repertorium 101, no. 11-12 (April 18, 2008): 590. http://dx.doi.org/10.1002/fedr.19901011103.
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Stanković, I., A. Bulajić, A. Vučurović, D. Ristić, K. Milojević, D. Nikolić, and B. Krstić. "First Report of Tomato spotted wilt virus on Chrysanthemum in Serbia." Plant Disease 97, no. 1 (January 2013): 150. http://dx.doi.org/10.1094/pdis-08-12-0778-pdn.
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In July 2011, greenhouse-grown chrysanthemum hybrid plants (Chrysanthemum × morifolium) with symptoms resembling those associated with tospoviruses were observed in the Kupusina locality (West Bačka District, Serbia). Disease incidence was estimated at 40%. Symptomatic plants with chlorotic ring spots and line patterns were sampled and tested by double antibody sandwich (DAS)-ELISA using polyclonal antisera (Bioreba AG, Reinach, Switzerland) against the two of the most devastating tospoviruses in the greenhouse floriculture industry: Tomato spotted wilt virus (TSWV) and Impatiens necrotic spot virus (INSV) (2). Commercial positive and negative controls and extracts from healthy chrysanthemum tissue were included in each ELISA. TSWV was detected serologically in 16 of 20 chrysanthemum samples and all tested samples were negative for INSV. The virus was mechanically transmitted from ELISA-positive chrysanthemum samples to five plants each of both Petunia × hybrida and Nicotiana tabacum ‘Samsun’ using chilled 0.01 M phosphate buffer (pH 7) containing 0.1% sodium sulfite. Inoculated plants produced local necrotic spots and systemic chlorotic/necrotic concentric rings, consistent with symptoms caused by TSWV (1). The presence of TSWV in ELISA-positive chrysanthemum plants and N. tabacum‘Samsun’ was further confirmed by conventional reverse transcription (RT)-PCR. Total RNAs were extracted with an RNeasy Plant Mini Kit (Qiagen, Hilden, Germany). RT-PCR was performed with the One-Step RT-PCR Kit (Qiagen) using primers TSWVCP-f/TSWVCP-r specific to the nucleocapsid protein (N) gene (4). A Serbian isolate of TSWV from tobacco (GenBank Accession No. GQ373173) and RNA extracted from a healthy chrysanthemum plant were used as positive and negative controls, respectively. An amplicon of the correct predicted size (738-bp) was obtained from each of the plants assayed, and that derived from chrysanthemum isolate 529-11 was purified (QIAqick PCR Purification Kit, Qiagen) and sequenced (JQ692106). Sequence analysis of the partial N gene, conducted with MEGA5 software, revealed the highest nucleotide identity of 99.6% (99% amino acid identity) with 12 TSWV isolates deposited in GenBank originating from different hosts from Italy (HQ830186-87, DQ431237-38, DQ398945), Montenegro (GU355939-40, GU339506, GU339508), France (FR693055-56), and the Czech Republic (AJ296599). The consensus maximum parsimony tree obtained on a 705-bp partial N gene sequence of TSWV isolates available in GenBank revealed that Serbian TSWV isolate 529-11 from chrysanthemum was clustered in the European subpopulation 2, while the Serbian isolates from tomato (GU369723) and tobacco (GQ373172-73 and GQ355467) were clustered in the European subpopulation 1 denoted previously (3). The distribution of TSWV in commercial chrysanthemum crops is wide (2). To our knowledge, this is the first report of TSWV infecting chrysanthemum in Serbia. Since chrysanthemum popularity and returns have been rising rapidly, the presence of TSWV may significantly reduce quality of crops in Serbia. References: (1) Anonymous. OEPP/EPPO Bull. 34:271, 2004. (2) Daughtrey et al. Plant Dis. 81:1220, 1997. (3) I. Stanković et al. Acta Virol. 55:337, 2011. (4) A. Vučurović et al. Eur. J. Plant Pathol. 133:935, 2012.
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Zheng, Y. X., C. C. Chen, and F. J. Jan. "First Report of Carnation mottle virus in Phalaenopsis Orchids." Plant Disease 95, no. 3 (March 2011): 354. http://dx.doi.org/10.1094/pdis-10-10-0757.
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In November 2003, two Phalaenopsis orchids from two different nurseries with symptoms of chlorotic rings on leaves were observed in Changhua County of central Taiwan. Symptomatic plants were collected and examined for the presence of viruses. Electron microscopic examination of ultrathin sections of leaf tissues from the symptomatic orchids found isometric virions of 32 nm in diameter. Subsequently, an isolate (herein designated as ‘92-orchid-1’) with particles of similar size were isolated from one symptomatic orchid and established in Chenopodium quinoa (3). After indirect ELISA tests using antisera against Carnation mottle virus (CarMV), Cucumber mosaic virus, Cymbidium ringspot virus, Tomato bushy stunt virus, Capsicum chlorosis virus, Impatiens necrotic spot virus, Tomato spotted wilt virus, Tomato ringspot virus, and Lisianthus necrosis virus, this isolate reacted positively with the antiserum produced against CarMV (1). CarMV-TW-infected and healthy C. quinoa were used as positive and negative controls, respectively. To further characterize this virus, the conserved region of the polymerase gene (ORF1RT) of Carmoviruses was amplified with degenerate primer pairs, FJJ2003-17 (5′-TATATCTCGAGCAA(A/C)TAGGGG(G/T)GCCT) and FJJ2003-18 (5′-TATAGGATCCCC(C/T)A(A/T)(A/G)GC(A/T)GTGTTCA), by reverse transcription (RT)-PCR using the total RNA isolated from the leaves of 92-orchid-1-, CarMV-TW-infected, and healthy C. quinoa (3). The 894-nt ORF1RT conserved region of isolate 92-orchid-1 (GenBank Accession No. HQ117873) shared 97.1, 65.6, 61.7, and 63.5% nucleotide identities and 98.3, 70.2, 66.1, and 64.7% amino acid identities with those of CarMV (X02986), Pelargonium flower break virus (NC_005286), Saguaro cactus virus (NC_001780), and Angelonia flower break virus (NC_007733), respectively. The sequence comparison of the ORF1RT conserved region indicated that 92-orchid-1 was a carmovirus related to CarMV. Sequence analyses of the coat protein (CP) gene (GenBank Accession No. HQ117872) amplified with the specific CP primer pairs of CarMV (FJJ2004-53: 5′-ACTGCGCTCGAGCTACTCTGTTGACAGTTCTA, and 2004-54: 5′-ATATATGGATCCCGTCCCGCCGTGTGTGTCTA) showed the isolate shared 95.8 to 98.8% nucleotide identities and 96.8 to 98.9% amino acid identities with those of 40 CarMV isolates. Furthermore, the CP gene shared 96.9, 97.0, and 98.8% nucleotide identities and 98.0, 95.7, and 98.3% amino acid identities with isolates from carnation (GenBank Accession No. AY383566) (1), calla lily (GenBank Accession No. HQ117870) (2), and lisianthus (GenBank Accession No. FJ843021), respectively, in Taiwan. These results suggested that this isolate was CarMV but distinct from the above-mentioned three isolates and designated CarMV-Ph. From 2004 to 2007, a further survey of 280 symptomatic Phalaenopsis plants by ELISA using CarMV polyclonal antibodies (1) found that approximately 4% of those tested were infected. To our knowledge, this is the first report of CarMV in Phalaenopsis orchids and the occurrence has substantial implications for the important nursery and floral industry in Taiwan. References: (1) C. C. Chen et al. Plant Pathol. Bull. 12:199, 2003. (2) C. C. Chen et al. Plant Dis. 87:1539, 2003. (3) Y. X. Zheng et al. Eur. J. Plant Pathol. 121:87, 2008.
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Staniulis, J., J. Stankiene, K. Sasnauskas, and A. Dargeviciute. "First Report of Sharka Disease Caused by Plum Pox Virus in Lithuania." Plant Disease 82, no. 12 (December 1998): 1405. http://dx.doi.org/10.1094/pdis.1998.82.12.1405c.
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Plum pox (sharka) disease caused by plum pox potyvirus (PPV) is considered the most important virus disease of stone fruit trees in Europe and the Mediterranean region. Nearly all those countries that produce stone fruits are affected (3). The causal virus of the disease is a European Plant Protection Organization A2 quarantine pathogen. Symptoms of leaf mottling, diffuse chlorotic spots, rings, and vein banding of varied intensity characteristic for plum pox virus infection were observed in the plum (Prunus domestica) orchard tree collection of the Lithuanian Institute of Horticulture in Babtai in 1996. Presence of this virus in the diseased trees was confirmed by double antibody sandwich-enzyme-linked immunosorbent assay (DAS-ELISA) with kits from BIOREBA (Reinach, Switzerland) and by polyclonal antibodies raised against a Moldavian isolate of PPV courtesy of T. D. Verderevskaya (Institute of Horticulture, Kishinev, Moldova). ELISAs with both sources of antiserum were positive for presence of PPV. Electron microscopy revealed the presence of potyvirus-like particles averaging 770 nm in extracts of mechanically inoculated plants of Chenopodium foetidum (chlorotic LL [local lesions]) and Pisum sativum cvs. Rainiai and Citron (mottling). For molecular diagnosis and characterization of this isolate, PPV-971, reverse transcription-polymerase chain reaction (RT-PCR) was employed. Total RNA from the leaves of infected pea was isolated as described (2). High molecular weight RNA selectively precipitated with 2 M lithium chloride was used for RT-PCR amplification of the coat protein encoding sequence by use of specific primers complementary to 5′ and 3′ parts of PPV coat protein L1 (GenBank accession no. X81081). Amino acid sequence comparison with GenBank data indicated 98.2% similarity with coat protein of PPV potyvirus isolated by E. Mais et al. (accession no. X81083) and 97.3% with PPV strain Rankovic (1).The specific DNA fragment, corresponding to predicted coat protein sequence size, was cloned into Escherichia coli pUC57 for DNA sequencing. Expression of the cloned sequence in bacteria and yeast expression systems is under investigation. The presence of PPV in plum trees in the 9-year-old collection at Babtai was confirmed by DAS-ELISA in 1997 and again in 1998. PPV was then detected in 20% of symptomatic trees of three cultivars. The Lithuanian PPV isolate reacted positively with “universal” Mab.5b and with a Mab (Mab.4DG5) specific for PPV-D. No reaction was observed with Mabs specific for PPV-M (Mab.AL), PPV-C (Mab.AC and Mab.TUV), and PPV-El Amar (Mab.EA24). PPV-971 seems to be a typical member of the less aggressive Dideron strain cluster of PPV (D. Boscia, personal communication). This is the first report of PPV in Lithuania and confirms the necessity for continuing the precautionary measures established in this country for indexing of nursery plum trees used for graft propagation. References: (1) S. Lain et al. Virus Res. 13:157, 1989. (2) J. Logemann et al. Anal. Biochem. 163:16, 1987. (3) M. Nemeth. OEPP/EPPO Bull. 24:525, 1994.
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Khanal, Pawan, Karthik R. Peddireddy, Juexin Marfai, Ryan McGorty, and Rae M. Robertson-Anderson. "DNA topology dictates emergent bulk elasticity and hindered macromolecular diffusion in DNA-dextran composites." Journal of Rheology 66, no. 4 (July 2022): 699–715. http://dx.doi.org/10.1122/8.0000447.
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Polymer architecture plays critical roles in both bulk rheological properties and microscale macromolecular dynamics in entangled polymer solutions and composites. Ring polymers, in particular, have been the topic of much debate due to the inability of the celebrated reptation model to capture their observed dynamics. Macrorheology and differential dynamic microscopy (DDM) are powerful methods to determine entangled polymer dynamics across scales; yet, they typically require different samples under different conditions, preventing direct coupling of bulk rheological properties to the underlying macromolecular dynamics. Here, we perform macrorheology on composites of highly overlapping DNA and dextran polymers, focusing on the role of DNA topology (rings versus linear chains) as well as the relative volume fractions of DNA and dextran. On the same samples under the same conditions, we perform DDM and single-molecule tracking on embedded fluorescent-labeled DNA molecules immediately before and after bulk measurements. We show DNA-dextran composites exhibit unexpected nonmonotonic dependences of bulk viscoelasticity and molecular-level transport properties on the fraction of DNA comprising the composites, with characteristics that are strongly dependent on the DNA topology. We rationalize our results as arising from stretching and bundling of linear DNA versus compaction, swelling, and threading of rings driven by dextran-mediated depletion interactions.