Journal articles: 'M-PBI'

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Kumar, V. Vijaya, C. Ramesh Kumar, A. Suresh, S. Jayalakshmi, U. Kamachi Mudali, and N. Sivaraman. "Evaluation of polybenzimidazole-based polymers for the removal of uranium, thorium and palladium from aqueous medium." Royal Society Open Science 5, no. 6 (June 2018): 171701. http://dx.doi.org/10.1098/rsos.171701.

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Four types of polybenzimidazole (PBI)-based polymers ( m -PBI, p -PBI, pyridine-based m -PBI and alkylated m -PBI) have been prepared and characterized. Extraction behaviour of heavy metal ions, viz. U(VI), Th(IV) and Pd(II), with these polymers was investigated. Distribution ratios for the extraction of these metal ions were measured as a function of nitric acid concentration. Extraction data reveal that, in general, p -PBI exhibits a higher distribution ratio for U(VI), Th(IV) and Pd(II) compared with the other polymeric resins evaluated in the present study. Column chromatography experiments were carried out with a solution of U(VI), Th(IV) and Pd(II) in dilute nitric acid media using columns packed with m - and p -PBI polymeric material for understanding the sorption and elution behaviour. The p -PBI-based resin has shown higher palladium sorption capacity (1.8 mmol g −1 ). The studies also established that p -PBI resin is a potential candidate material for the recovery of U(VI) and Th(IV) (capacity 0.22 mmol g −1 and 0.13 mmol g −1 ) from an aqueous stream, e.g. mine water samples.

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Xiao, Li, Jia Xu, Jing Chen, Jicheng Luan, Yi Yang, Bing Zhang, Jianxi Yao, and Songyuan Dai. "Interface modification effects using a halide-free lead source for perovskite solar cells." Sustainable Energy & Fuels 1, no. 6 (2017): 1358–65. http://dx.doi.org/10.1039/c7se00200a.

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The control over remnant PbI₂ at the m-TiO₂/CH₃NH₃PbI₃ interface by PbAc₂ solution provides an efficient way to reduce carrier recombination.

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Fuentes, Isabel, Andreu Andrio, Abel García-Bernabé, Jorge Escorihuela, Clara Viñas, Francesc Teixidor, and Vicente Compañ. "Structural and dielectric properties of cobaltacarborane composite polybenzimidazole membranes as solid polymer electrolytes at high temperature." Physical Chemistry Chemical Physics 20, no. 15 (2018): 10173–84. http://dx.doi.org/10.1039/c8cp00372f.

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Escorihuela, Jorge, Abel García-Bernabé, and Vicente Compañ. "A Deep Insight into Different Acidic Additives as Doping Agents for Enhancing Proton Conductivity on Polybenzimidazole Membranes." Polymers 12, no. 6 (June 18, 2020): 1374. http://dx.doi.org/10.3390/polym12061374.

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The use of phosphoric acid doped polybenzimidazole (PBI) membranes for fuel cell applications has been extensively studied in the past decades. In this article, we present a systematic study of the physicochemical properties and proton conductivity of PBI membranes doped with the commonly used phosphoric acid at different concentrations (0.1, 1, and 14 M), and with other alternative acids such as phytic acid (0.075 M) and phosphotungstic acid (HPW, 0.1 M). The use of these three acids was reflected in the formation of channels in the polymeric network as observed by cross-section SEM images. The acid doping enhanced proton conductivity of PBI membranes and, after doping, these conducting materials maintained their mechanical properties and thermal stability for their application as proton exchange membrane fuel cells, capable of operating at intermediate or high temperatures. Under doping with similar acidic concentrations, membranes with phytic acid displayed a superior conducting behavior when compared to doping with phosphoric acid or phosphotungstic acid.

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Bolland, M. D. A., and D. G. Allen. "Phosphorus sorption by sandy soils from Western Australia: effect of previously sorbed P on P buffer capacity and single-point P sorption indices." Soil Research 41, no. 7 (2003): 1369. http://dx.doi.org/10.1071/sr02098.

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Soil samples collected from 8 field experiments in Western Australia to which 5–8 amounts of superphosphate had been applied once only 13–23 years previously were used to measure the phosphorus (P) buffer capacity of soil (PBC) and P sorption by several single-point indices. PBC was estimated from well-defined P sorption curves when several levels of P were added to soil suspensions, and was the amount of P sorbed when the concentration of P in the final solution was raised from 0.25 to 0.35 mg P/L. The single-point P sorption indices were measured by adding one amount of P (10 mg P/L) to soil suspensions (1 : 20, soil : 0.02 M KCl or 0.01 M CaCl2). Three indices were calculated from the amount of P sorbed by soil (S, mg P/kg soil) and the amount of P in solution (c, mg P/L)—(1) the phosphorus retention index (PRI, S/c [L/kg]), (2) the Freundlich retention index (FRI, S/c0.35 [dimensionless]), and (3) the phosphorus sorption index (PSI, S/log10 [c × 1000] [dimensionless])—to provide PRI K & Ca, FRI K & Ca, and PSI K & Ca values. P sorption was also measured by the P buffer index (PBI), the new single-point P sorption index recommended for national use, to provide PBICa values. To estimate the previous P sorbed by soil (native soil P is negligible for these soils, so previously sorbed P originates from fertiliser P applied in a previous year), the amount of P extracted by 0.5 M sodium bicarbonate from soil (Colwell soil test P) was added to the amount of P sorbed by soil to calculate PRI*K & Ca, FRI*K & Ca, PSI*K & Ca, and PBI*Ca values. In addition, previously sorbed P was estimated using the q coefficient of the Freundlich equation; q was added to P sorption to calculate PSI**, FRI**, PSI** and PBI** values to take account of previously sorbed P.For the 8 experiments, PBC values significantly decreased where more fertiliser P had been applied to the soils 13–23 years previously. This indicated that the capacity of the 8 soils to sorb P decreased as more P was applied in a previous year, and a single-point P sorption index would need to reflect this decrease. As the amount of P applied to soil in the field plots increased, the following trends occurred : (1) Colwell soil test P always increased; (2) PRIK & Ca, FRIK & Ca, PSIK & Ca, and PBICa consistently decreased; (3) PRI*K & Ca, FRI*K & Ca, PSI*K & Ca, and PBI*Ca mostly increased, but with some values being unaffected or decreasing; (4) PRI**, FRI**, PSI**, and PBI** values were largely unaffected by the amount of P applied in a previous year. Evidently, either adding Colwell soil test P or q to P sorption to calculate the single-point P sorption indices mostly overestimated P sorption by the sandy, low P sorbing soils used, but the overestimate was larger for Colwell soil test P than for q.

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Parrondo, Javier, Chitturi Venkateswara Rao, Sundara L. Ghatty, and B. Rambabu. "Electrochemical Performance Measurements of PBI-Based High-Temperature PEMFCs." International Journal of Electrochemistry 2011 (2011): 1–8. http://dx.doi.org/10.4061/2011/261065.

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Acid-doped poly(2,2′-m-phenylene-5,5′-bibenzimidazole) membranes have been prepared and used to assemble membrane electrode assemblies (MEAs) with various contents of PBI (1–30 wt.%) in the gas diffusion electrode (GDE). The MEAs were tested in the temperature range of140∘C–200∘C showing that the PBI content in the electrocatalyst layer influences strongly the electrochemical performance of the fuel cell. The MEAs were assembled using polyphosphoric acid doped PBI membranes having conductivities of 0.1 Scm−1at180∘C. The ionic resistance of the cathode decreased from 0.29 to 0.14 Ohm-cm2(180∘C) when the content of PBI is varied from 1 to 10 wt.%. Similarly, the mass transfer resistance or Warburg impedance increased 2.5 times, reaching values of 6 Ohm-cm2. 5 wt.% PBI-based MEA showed the best performance. The electrochemical impedance measurements were in good agreement with the fuel cell polarization curves obtained, and the optimum performance was obtained when overall resistance was minimal.

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Paglia, L., V. Genova, M. P. Bracciale, C. Bartuli, F. Marra, M. Natali, and G. Pulci. "Thermochemical characterization of polybenzimidazole with and without nano-ZrO2 for ablative materials application." Journal of Thermal Analysis and Calorimetry 142, no. 5 (October 28, 2020): 2149–61. http://dx.doi.org/10.1007/s10973-020-10343-4.

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AbstractDuring the ballistic atmospheric re-entry, a space vehicle has to withstand huge thermo-mechanical solicitations because of its high velocity and the friction with the atmosphere. According to the kind of the re-entry mission, the heat fluxes can be very high (in the order of some MW m−2) ;thus, an adequate thermal protection system is mandatory in order to preserve the structure of the vehicle, the payload and, for manned mission, the crew. Carbon phenolic ablators have been chosen for several missions because they are able to dissipate the incident heat flux very efficiently. Phenolic resin presents satisfying performance but also environmental drawbacks. Thus, a more environmental-friendly solution was conceived: a high-performance thermoplastic material, polybenzimidazole (PBI), was employed instead of phenolic resin. In this work PBI-ablative material samples were manufactured with and without the addition of nano-ZrO2 and tested with an oxyacetylene flame. For comparison, some carbon-phenolic ablators with the same density were manufactured and tested too. Thermogravimetric analysis on PBI samples was carried out at different heating rates, and the obtained TG data were elaborated to evaluate the activation energy of PBI and nano-filled PBI. The thermokinetics results for PBI show an improvement in thermal stability due to the addition of nano-ZrO2, while the oxyacetylene flame test enlightens how PBI ablators are able to overcome the carbon phenolic ablators performance, in particular when modified by the addition of nano-ZrO2.

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Lee, Sangrae, Ki-Ho Nam, Kwangwon Seo, Gunhwi Kim, and Haksoo Han. "Phase Inversion-Induced Porous Polybenzimidazole Fuel Cell Membranes: An Efficient Architecture for High-Temperature Water-Free Proton Transport." Polymers 12, no. 7 (July 19, 2020): 1604. http://dx.doi.org/10.3390/polym12071604.

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To cope with the demand for cleaner alternative energy, polymer electrolyte membrane fuel cells (PEMFCs) have received significant research attention owing to their high-power density, high fuel efficiency, and low polluting by-product. However, the water requirement of these cells has necessitated research on systems that do not require water and/or use other mediums with higher boiling points. In this work, a highly porous meta-polybenzimidazole (m-PBI) membrane was fabricated through the non-solvent induced phase inversion technique and thermal cross-linking for high-temperature PEMFC (HT-PEMFC) applications. Standard non-thermally treated porous membranes are susceptible to phosphoric acid (PA) even at low concentrations and are unsuitable as polymer electrolyte membranes (PEMs). With the porous structure of m-PBI membranes, higher PA uptake and minimal swelling, which is controlled via cross-linking, was achieved. In addition, the membranes exhibited partial asymmetrical morphology and are directly applicable to fuel cell systems without any further modifications. Membranes with insufficient cross-linking resulted in an unstable performance in HT-PEMFC environments. By optimizing thermal treatment, a high-performance membrane with limited swelling and improved proton conductivity was achieved. Finally, the m-PBI membrane exhibited enhanced acid retention, proton conductivity, and fuel cell performance.

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Meng, Chao, Sheng Huang, Dongmei Han, Shan Ren, Shuanjin Wang, and Min Xiao. "Semi-interpenetrating Network Membrane from Polyethyleneimine-Epoxy Resin and Polybenzimidazole for HT-PEM Fuel Cells." Advances in Polymer Technology 2020 (December 29, 2020): 1–8. http://dx.doi.org/10.1155/2020/3845982.

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In the present work, a semi-interpenetrating network (semi-IPN) high-temperature proton exchange membrane based on polyethyleneimine (PEI), epoxy resin (ER), and polybenzimidazole (PBI) was prepared and characterized, aiming at their future application in fuel cell devices. The physical properties of the semi-IPN membrane are characterized by thermogravimetric analysis (TGA) and tensile strength test. The results indicate that the as-prepared PEI-ER/PBI semi-IPN membranes possess excellent thermal stability and mechanical strength. After phosphoric acid (PA) doping treatment, the semi-IPN membranes show high proton conductivities. PA doping level and volume swelling ratio as well as proton conductivities of the semi-IPN membranes are found to be positively related to the PEI content. High proton conductivities of 3.9 ∽ 7.8 × 10 − 2 S c m − 1 are achieved at 160°C for these PA-doped PEI-ER/PBI series membranes. H2/O2 fuel cell assembled with PA-doped PEI-ER(1 : 2)/PBI membrane delivered a peak power density of 170 mW cm-2 at 160°C under anhydrous conditions.

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Верещагин, А. Л., О. Б. Кудряшова, Е. А. Морозова, Н. В. Бычин, and А. Н. Паседкина. "SONOCHEMICAL SYNTHESIS OF LEAD IODIDE." Южно-Сибирский научный вестник, no. 2(36) (April 30, 2021): 31–39. http://dx.doi.org/10.25699/sssb.2021.36.2.025.

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Йодид свинца образовывался при дозировании 0,02 М раствора KI в эквивалентное количество 0,01 М Pb(CH3COO)2 при комнатной температуре (с добавлением уксусной кислоты) и при ультразвуковом облучении с интенсивностью 8 или 16 Вт/см2. Установлено, что морфология частиц PbI2 образующегося при ультразвуковом облучении определяется рН среды. При рН 2,8…2,9 имеет место увеличение размера частиц в результате сварки вследствие столкновения частиц. Методом сканирующей электронной микроскопии обнаружены следы оплавления частиц и следы соударений. При рН 4,5…4,6 происходит диспергирование частиц вследствие соногидролиза и образования PbI(OH). Морфология образующихся частиц также зависит от способа получения: при дозировании йодида калия в раствор ацетата свинца образуются звездообразные структуры, при перекристаллизации – гексагональные пластины – во всех случаях размером порядка 10 мкм. Lead iodide was formed by dosing 0.02 M KI solution into an equivalent amount of 0.01 M Pb (CH3COO) 2 at room temperature (with the addition of acetic acid) and under ultrasonic irradiation with an intensity of 8 or 16 W / cm2. It was found that the morphology of PbI2 particles formed under ultrasonic irradiation is determined by the pH of the medium. At pH 2.8 ... 2.9, there is an increase in the particle size as a result of welding due to the collision of particles. Scanning electron microscopy revealed traces of particle fusion and impact traces. At pH 4.5 ... 4.6, the particles are dispersed due to sonohydrolysis and the formation of PbI (OH). The morphology of the resulting particles also depends on the method of production: when dosing potassium iodide into a solution of lead acetate, star-shaped structures are formed, during recrystallization, hexagonal plates are formed, in all cases about 10 μm in size

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Kim, Sung-Kon. "Polybenzimidazole and Phosphonic Acid Groups-Functionalized Polyhedral Oligomeric Silsesquioxane Composite Electrolyte for High Temperature Proton Exchange Membrane." Journal of Nanomaterials 2016 (2016): 1–7. http://dx.doi.org/10.1155/2016/2954147.

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Here, we report composite membrane consisting of poly[2,2′-(m-phenylene)-5,5′-(bibenzimidazole)] (PBI) and polyhedral oligomeric silsesquioxane functionalized with phosphonic acid groups (PO(OH)2-POSS) for high temperature proton exchange membrane. ~7 phosphonic acid groups are incorporated into the phenyl rings of POSS via bromination in a high yield (~93%), followed by substitution of the bromine elements by phosphonate ester groupsviaa Pd(0) catalyzed P–C coupling reaction. Phosphonic acid groups are formed by the hydrolysis of the phosphonate ester groups in hydrobromic acid solution. At a 50 wt% of PA content in the membranes, PBI/PO(OH)2-POSS composite membrane shows larger proton conductivity of 3.2 × 10−3 S cm−1than 2.8 × 10−3 S cm−1of PBI membrane at 150°C and anhydrous conditions, owing to the multiple phosphonic acid groups of PO(OH)2-POSS that can function as proton transport medium at high temperature and low humidity conditions.

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Herranz, Daniel, Roxana E. Coppola, Ricardo Escudero-Cid, Kerly Ochoa-Romero, Norma B. D’Accorso, Juan Carlos Pérez-Flores, Jesús Canales-Vázquez, Carlos Palacio, Graciela C. Abuin, and Pilar Ocón. "Application of Crosslinked Polybenzimidazole-Poly(Vinyl Benzyl Chloride) Anion Exchange Membranes in Direct Ethanol Fuel Cells." Membranes 10, no. 11 (November 17, 2020): 349. http://dx.doi.org/10.3390/membranes10110349.

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Crosslinked membranes have been synthesized by a casting process using polybenzimidazole (PBI) and poly(vinyl benzyl chloride) (PVBC). The membranes were quaternized with 1,4-diazabicyclo[2.2.2]octane (DABCO) to obtain fixed positive quaternary ammonium groups. XPS analysis has showed insights into the changes from crosslinked to quaternized membranes, demonstrating that the crosslinking reaction and the incorporation of DABCO have occurred, while the 13C-NMR corroborates the reaction of DABCO with PVBC only by one nitrogen atom. Mechanical properties were evaluated, obtaining maximum stress values around 72 MPa and 40 MPa for crosslinked and quaternized membranes, respectively. Resistance to oxidative media was also satisfactory and the membranes were evaluated in single direct ethanol fuel cell. PBI-c-PVBC/OH 1:2 membrane obtained 66 mW cm−2 peak power density, 25% higher than commercial PBI membranes, using 0.5 bar backpressure of pure O2 in the cathode and 1 mL min−1 KOH 2M EtOH 2 M aqueous solution in the anode. When the pressure was increased, the best performance was obtained by the same membrane, reaching 70 mW cm−2 peak power density at 2 bar O2 backpressure. Based on the characterization and single cell performance, PBI-c-PVBC/OH membranes are considered promising candidates as anion exchange electrolytes for direct ethanol fuel cells.

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Arredondo, Marcial, Pilar Hurtado, Montserrat Sabaté, Carla Uriarte Chávarri, and Luis Botella. "Programa de Entrenamiento en Mindfulness Basado en Prácticas Breves Integradas (M-PBI)." Revista de Psicoterapia 27, no. 103 (March 1, 2016): 133–50. http://dx.doi.org/10.33898/rdp.v27i103.109.

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El programa de entrenamiento en Mindfulness basado en Prácticas Breves Integradas (M-PBI) es una propuesta que nace con el objetivo de hacer lo más accesible posible la práctica de mindfulness tanto a la población general como a personas que puedan estar en tratamiento psicológico sin tener un trastorno grave o en estar en fase aguda. Se ha diseñado un protocolo que conserva la estructura de los programas de entrenamiento en mindfulness y compasión de 8 semanas que han probado su eficacia y han sido validados. En este programa se han reducido los tiempos de prácticas habituales y se ha promovido el poder realizar las prácticas “allí donde sea posible”, al tiempo que se ha mantenido la eficacia del cambio demostrada en los programas validados. Para facilitar el proceso de aprendizaje, se ha diseñado una App (Mindfulness Focus Now) que incluye las prácticas formales del entrenamiento. El programa cuenta también con recursos en la web www.mindfulnessypsicologiabcn.com y se han incorporado varias Apps que facilitan la accesibilidad, mensurabilidad y guía de diferentes tipos de prácticas, incluyendo una medida de variabilidad de la frecuencia cardíaca (heart rate variability, HRV).

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Arredondo, Marcial, Montserrat Sabaté, Luis Botella, Pilar Hurtado Villar, and Lesly María Acosta Argueta. "Estudio Piloto del Programa de Entrenamiento en Mindfulness Basado en Prácticas Breves Integradas (M-PBI)." Revista de Psicoterapia 27, no. 103 (March 1, 2016): 151–68. http://dx.doi.org/10.33898/rdp.v27i103.110.

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El objetivo de este estudio es valorar los primeros resultados del programa de mindfulness basado en prácticas breves integradas (M-PBI) en cuanto a su efecto sobre la capacidad de mindfulness (mediante el Five Facet Mindfulness Questionnaire, FFMQ), descentramiento (Experiences Questionnaire-Decentering, EQ-D) y síntomas de depresión, ansiedad y estrés (Depression Anxiety and Stress Scale, DASS-21). Se incluyeron 74 participantes y la totalidad finalizaron el estudio. La media de edad fue de 38.9 años (DE = 9), el 74.3% fueron mujeres y el 87% estaban laboralmente en activo. Las puntuaciones medias del FFMQ y EQ-D aumentaron significativamente y las del DASS-21 disminuyeron de forma también significativa en la medición post-entrenamiento vs. pre-entrenamiento (p <.0001, en todos los casos). Los cambios más altos se dieron en el aumento de la capacidad de descentramiento (cambio medio de 7.6 puntos; IC95%: 5.8 a 9.4), disminución del estrés (-6.6; IC95%: -8.5 a -4.8) y en la mejoría de tres facetas del FFMQ (no juicio, no reactividad y capacidad de observación: 5.8 [IC95%: 4 a 8.1], 4.9 [IC95%: 3.5 a 6.5] y 5.3 [IC95%: 4.4 a 6.3] respectivamente). Estos cambios parecen no depender de la edad, sexo, estar en tratamiento psicológico, profesión o tener práctica de meditación y motivación para la realización del programa. Como conclusión, estos primeros resultados sugieren que el entrenamiento en el programa M-PBI conlleva un aumento de las capacidades de mindfulness y descentramiento y una reducción de los síntomas de estrés, ansiedad y depresión. No obstante se requieren futuros estudios con un diseño aleatorizado y grupo control para confirmar estos resultados y controlar los posibles factores de confusión, así como minimizar los sesgos.

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Sordini, Laura, João C. Silva, Fábio F. F. Garrudo, Carlos A. V. Rodrigues, Ana C. Marques, Robert J. Linhardt, Joaquim M. S. Cabral, Jorge Morgado, and Frederico Castelo Ferreira. "PEDOT:PSS-Coated Polybenzimidazole Electroconductive Nanofibers for Biomedical Applications." Polymers 13, no. 16 (August 19, 2021): 2786. http://dx.doi.org/10.3390/polym13162786.

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Bioelectricity drives several processes in the human body. The development of new materials that can deliver electrical stimuli is gaining increasing attention in the field of tissue engineering. In this work, novel, highly electrically conductive nanofibers made of poly [2,2′-m-(phenylene)-5,5′-bibenzimidazole] (PBI) have been manufactured by electrospinning and then coated with cross-linked poly (3,4-ethylenedioxythiophene) doped with poly (styrene sulfonic acid) (PEDOT:PSS) by spin coating or dip coating. These scaffolds have been characterized by scanning electron microscopy (SEM) imaging and attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy. The electrical conductivity was measured by the four-probe method at values of 28.3 S·m−1 for spin coated fibers and 147 S·m−1 for dip coated samples, which correspond, respectively, to an increase of about 105 and 106 times in relation to the electrical conductivity of PBI fibers. Human bone marrow-derived mesenchymal stromal cells (hBM-MSCs) cultured on the produced scaffolds for one week showed high viability, typical morphology and proliferative capacity, as demonstrated by calcein fluorescence staining, 4′,6-diamidino-2-phenylindole (DAPI)/Phalloidin staining and MTT [3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide] assay. Therefore, all fiber samples demonstrated biocompatibility. Overall, our findings highlight the great potential of PEDOT:PSS-coated PBI electrospun scaffolds for a wide variety of biomedical applications, including their use as reliable in vitro models to study pathologies and the development of strategies for the regeneration of electroactive tissues or in the design of new electrodes for in vivo electrical stimulation protocols.

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Chen, R. T., J. J. Rafalko, and L. C. Sawyer. "Characterization of high-performance polymer blends." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 350–51. http://dx.doi.org/10.1017/s0424820100153725.

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Blending of polymers, a method used to engineer materials to provide specific properties, has been extended to high performance materials being developed for composite applications in the aerospace industry. The high performance requirements of such blends demand a complete understanding of the chemistry and morphology as a function of end-use temperatures. Multidisciplinary protocols for characterization of blends include microscopy, infrared and thermal analysis. The major issues involved in such a study of polymer blends will be described.Recently the Hoechst Celanese polybenzimidazole, [poly-2,2′(m-phenylene)-5,5′ bibenzimidazole], PBI, and the General Electric aromatic polyether imide [poly(2,2′-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane-m-phenylenediimine], Ultem 1000, which are being evaluated for aerospace applications, were found to form miscible blends. The large parts are being fabricated from fibers spun from concentrated solutions (dopes).

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Hornecker, Else, Torsten Muuß, Hannelore Ehrenreich, and Rainer F. Mausberg. "A Pilot Study on the Oral Conditions of Severely Alcohol Addicted Persons." Journal of Contemporary Dental Practice 4, no. 2 (2003): 51–59. http://dx.doi.org/10.5005/jcdp-4-2-51.

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Abstract The aim of this study was to investigate the oral status, drinking, smoking, and oral hygiene habits of alcoholics. One hundred severely addicted alcoholics were examined during the in-patient treatment for detoxification (mean age: 44 years; 68 males/32 females) The study included a questionnaire and an oral examination that measured DMF-T, QHI, PBI, and CPI. The majority of alcoholics were heavy smokers (>30 cigarettes/day). Fifty-two percent of the alcoholics stated they frequently forgot to brush their teeth and 43% observed bleeding of their gums. The mean DMF-T was 20 (2 D-T, 9 M-T, 9 F-T), the mean QHI was 2.4, and the mean PBI was 1.8. Forty-nine percent of the sextants were scored CPI 3 or 4; about 25% were edentulous (CPI X). Our results indicate severe alcoholics have a high risk of periodontal break down and tooth loss. To what extent these findings were caused by general/oral neglect alone (in combination with nicotine abuse) is at present unknown. Citation Hornecker E, Muuß T, Ehrenreich H, et. al. A Pilot Study on the Oral Conditions of Severely Alcohol Addicted Persons. J Contemp Dent Pract 2003 May;(4)2:051-059.

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Lu, Mengxue, Chengwu Shi, Chengfeng Ma, Nannan Li, Long Li, and Guannan Xiao. "High concentration PbI 2 ·DMSO complex precursor solution of 1.7 M in DMF for high-thickness and full-coverage CH 3 NH 3 PbI 3−x Br x thin films." Journal of Materials Science: Materials in Electronics 28, no. 7 (December 19, 2016): 5603–8. http://dx.doi.org/10.1007/s10854-016-6228-0.

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Johnson, Frederick E., and Israel Cabasso. "Synthesis and Mechanism of PBI Phosphonate, Poly[2,2′-(-m-phenylene)-5,5′-Bibenzimidazole Phosphonate Ester], and its Polyphosphonic Acid Derivatives." Macromolecules 43, no. 8 (April 27, 2010): 3634–51. http://dx.doi.org/10.1021/ma100320w.

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Hauser, Ulrike, Heide Krahl, Helmut Peters, Volker Fingerle, and Bettina Wilske. "Impact of Strain Heterogeneity on Lyme Disease Serology in Europe: Comparison of Enzyme-Linked Immunosorbent Assays Using Different Species of Borrelia burgdorferi Sensu Lato." Journal of Clinical Microbiology 36, no. 2 (1998): 427–36. http://dx.doi.org/10.1128/jcm.36.2.427-436.1998.

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For the standardization of serological tests for Lyme borreliosis (LB) in Europe, the influence of the heterogeneity of Borrelia burgdorferi sensu lato must be assessed in detail. For this study four immunoglobulin M (IgM) and IgG enzyme-linked immunosorbent assays (ELISAs) with octyl-β-d-glucopyranoside extracts of strains PKo (Borrelia afzelii), PBi (Borrelia garinii), and PKa2 and B31 (both B. burgdorferi sensu stricto) were compared. Strains PKo, PBi, and PKa2 at the passages used for antigen preparations abundantly expressed outer surface protein C (OspC), whereas strain B31 at the passage used for antigen preparation did not express OspC. Sera (all from Germany) from 222 patients with clinically defined LB of all stages, 133 blood donors, and 458 forest workers were tested. None of the forest workers had symptoms consistent with LB at the time that the samples were collected. For IgM tests, receiver operating characteristic curves demonstrated that discrimination between sera from patients and blood donors was best with strain PKo and worst with strain B31. The discriminatory abilities of the four IgG ELISAs were similar in a diagnostically reasonable specificity range (90 to 100%). More than 20% of the sera from forest workers reacted strongly in the PKo IgG ELISA (optical density value, >1.5; other assays, less than 8%). Western blots of the sera with the most discrepant ELISA results revealed almost exclusive reactivity with p17. This highly immunogenic antigen is only expressed by strain PKo. This observation might be important for the development of assays enabling discrimination between asymptomatic or previous infection and active disease.

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Firdausi, Nurul Jannatul, and Agus Aan Adriansyah. "GAMBARAN MANAJEMEN TEMPAT TIDUR RAWAT INAP KELAS 3 DI RSUD Dr. M. SOEWANDHIE SURABAYA." Medical Technology and Public Health Journal 2, no. 2 (October 29, 2018): 167–74. http://dx.doi.org/10.33086/mtphj.v2i2.570.

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National Health Insurance (JKN) has encouraged utilization of Inpatient Department (IPD).The highest improvement by poor who funded by JKN-PBI scheme. Unbalancing supply and demandare potentially making queuesand effect to prolonged waiting times. The study aims to define bedmanagement in the 3rd class IPD of RSUD. Dr. M. Soewandhie Surabaya. Type of study wasobservasional-descriptive with cross sectional design. Study was conducted in The 3rd Class IPD ofRSUD. Dr. M Soewandhi beginning on June to August 2018. Sample was patients who have beendecided to discharged from IPD. Sampling technique by simple random sampling. The sample sizewere 104 patients. Data collection by observing process of patients discharge to preparation ofinpatient rooms (cleaning and put on the linen). Analysis dat in narrative and supported by graphsand tables. The results: the peak time of patient discharge and patient admission has gap about 4hour time. Room booking is centralized at Administration, but updating data is constrained due togathering information by telephone to nurses in IPD. Cycle time to provide a bed for 165 minutes(Takt Time = 52 minutes). The longest process is waiting for patient discharge and cleaning services.Provision of inpatient rooms still long, so the hospital management needs to improve patient flow,administration and information when patient discharge untill room cleaning.

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Arredondo, M., M. Sabaté, N. Valveny, M. Langa, R. Dosantos, J. Moreno, and L. Botella. "A mindfulness training program based on brief practices (M-PBI) to reduce stress in the workplace: a randomised controlled pilot study." International Journal of Occupational and Environmental Health 23, no. 1 (January 2, 2017): 40–51. http://dx.doi.org/10.1080/10773525.2017.1386607.

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Li, Shuo, J. R. Fried, John Colebrook, and Jonathan Burkhardt. "Molecular simulations of neat, hydrated, and phosphoric acid-doped polybenzimidazoles. Part 1: Poly(2,2′-m-phenylene-5,5′-bibenzimidazole) (PBI), poly(2,5-benzimidazole) (ABPBI), and poly(p-phenylene benzobisimidazole) (PBDI)." Polymer 51, no. 23 (October 2010): 5640–48. http://dx.doi.org/10.1016/j.polymer.2010.09.021.

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24

Martínez, Manuel A., Elisa E. Greciano, Jorge Cuéllar, José M. Valpuesta, and Luis Sánchez. "Globular Aggregates Stemming from the Self-Assembly of an Amphiphilic N-Annulated Perylene Bisimide in Aqueous Media." Nanomaterials 11, no. 6 (May 31, 2021): 1457. http://dx.doi.org/10.3390/nano11061457.

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Herein, we describe the synthesis of highly emissive amphiphilic N-annulated PBI 1 decorated with oligo ethylene glycol (OEG) side chains. These polar side chains allow the straightforward solubility of 1 in solvents of different polarity such as water, iPrOH, dioxane, or chloroform. Compound 1 self-assembles in aqueous media by π-stacking of the aromatic units and van der Waals interactions, favored by the hydrophobic effect. The hypo- and hypsochromic effect observed in the UV-Vis spectra of 1 in water in comparison to chloroform is diagnostic of H-type aggregation. Solvent denaturation experiments allow deriving the free Gibbs energy for the self-assembly process in aqueous media and the factor m that is indicative of the influence exerted by a good solvent in the stability of the final aggregates. The ability of compound 1 to self-assemble in water yields globular aggregates that have been visualized by TEM imaging.

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Matic, Sava, Mirjana Ivanovic, and Predrag Nikolic. "Evaluation of a prevention programme efficiency for patients with fixed orthodontic appliances." Vojnosanitetski pregled 68, no. 3 (2011): 214–19. http://dx.doi.org/10.2298/vsp1103214m.

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Background/Aim. Orthodontic treatment enables the establishment of functional occlusion and improvement of oral health, however, it increases the risk of periodontal disease development. The aim of this paper was to examine the efficiency of the applied programme for the prevention of gingivitis in children undergoing the fixed orthodontic appliance therapy and to determine the most efficient devices and techniques for maintaining oral hygiene during orthodontic treatment. Methods. The study included 80 patients of both genders - 60 patients comprised the experimental group and 20 patients comprised the control group. All of them were patients of the Clinic for Orthodontics at the School of Dentistry in Belgrade, aged between 13 and 18. The Silness-L?e Plaque Index (PI) was utilised for the assessment of oral hygiene quality and Silness-L?e Gingival Index (GI) and M?hlemann Papilla Bleeding Index (PBI) were utilised for the assessment of gingival state. Checkups were conducted as a single-blind study at the beginning and after the first, the third and the sixth month of the preventive and prophylactic programme. Results. During the observed period, a statistically significant change in PI, GI and PBI values was noticed (p < 0.005), as well as the difference in the dynamics of value changes during the periods between the observed groups. Conclusion. The preventive programme, applied to children undergoing the fixed orthodontic appliance therapy, had a positive effect both on oral hygiene quality and gingival state. The values of the examined parameters of the patients from the experimental group were significantly lower in comparison with those of the patients from the control group. The most efficient combination of devices for oral hygiene during orthodontic treatment was: a Curaprox CP5460 toothbrush, CD Ortho 60 orthodontic toothbrush and Curaprox CPS 14 interdental brush.

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Rama Rao, P. V. S., S. Tulasi Ram, K. Niranjan, D. S. V. V. D. Prasad, S. Gopi Krishna, and N. K. M. Lakshmi. "VHF and L-band scintillation characteristics over an Indian low latitude station, Waltair (17.7° N, 83.3° E)." Annales Geophysicae 23, no. 7 (October 14, 2005): 2457–64. http://dx.doi.org/10.5194/angeo-23-2457-2005.

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Abstract. Characteristics of simultaneous VHF (244 MHz) and L-band (1.5 GHz) scintillations recorded at a low-latitude station, Waltair (17.7° N, 83.3° E), during the low sunspot activity year of March 2004 to March 2005, suggest that the occurrence of scintillations is mainly due to two types, namely the Plasma Bubble Induced (PBI), which maximizes during the post sunset hours of winter and equinoctial months, and the Bottom Side Sinusoidal (BSS) type, which maximizes during the post-midnight hours of the summer solstice months. A detailed study on the spectral characteristics of the scintillations at both the frequencies show that the post-sunset scintillations are strong with fast fading (≈40 fad/min) and are multiple in nature in scattering, giving rise to steep spectral slopes, whereas the post-midnight scintillations, which occur mostly on the VHF signal with low fading rate (≈4 fad/min), are of the BSS type, often showing typical Fresnel oscillations with reduced roll off spectral slopes, indicating that the type of irregularity resembles a thin screen structure giving rise to weak scattering. Using the onset times of several similar scintillation patches across the two satellite (FLEETSAT 73° E, INMARSAT 65° E) ray paths (sub-ionospheric points are separated by 82 km), the East ward movement of the irregularity patches is found to vary from 150 to 250 m/s during the post sunset hours and decrease slowly during the post midnight hours. Further, the east-west extent of the PBI type of irregularities is found to vary from 100 to 500 km, while that of the BSS type extend up to a few thousand kilometers. Keywords. Ionosphere (Ionospheric irregularities; Auroral ionosphere; Electric fields and currents)

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Tsfasman, T. M., S. G. Markushin, I. I. Akopova, and Y. Z. Ghendon. "Molecular mechanisms of reversion to the ts+ (non-temperature-sensitive) phenotype of influenza A cold-adapted (ca) virus strains." Journal of General Virology 88, no. 10 (October 1, 2007): 2724–29. http://dx.doi.org/10.1099/vir.0.83014-0.

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A ts+ ca− (non-temperature-sensitive, non-cold-adapted) revertant of the A/Leningrad/134/47/57 ca strain influenza virus [A/Leningrad/134/47/ts+18/1957(H2N2)], obtained in our previous study, lost phenotypic manifestation of ts mutations by the PB2, NP and NS genes, although, according to sequencing data, it acquired only two true reversions of a mutation in the PB2 and PB1 genes. Direct sequencing showed the appearance of 27 additional mutations (13 coding) in the genes encoding the PB2, PB1, PA, NP, M and NS proteins of the revertant, along with the above-mentioned two true reversions. We conjecture that some of these mutations suppressed phenotypic manifestation of ts mutations in the NS and NP genes.

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Putra, Fauzan Junanda, Al-Hafiz Al-Hafiz, and Firdawati Firdawati. "Hubungan Karakteristik Pasien dengan Tingkat Kepuasan Pelayanan pada Pasien Operasi Sub Bagian Fasial Plastik dan Bedah Rekonstruksi Bagian THT-KL RSUP Dr. M. Djamil Tahun 2019." Jurnal Ilmu Kesehatan Indonesia 1, no. 3 (May 23, 2021): 278–88. http://dx.doi.org/10.25077/jikesi.v1i3.83.

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Hospitals play an important role in providing quality public services. The success of a hospital in providing services can be seen from the performance of health care provider and patient satisfaction. Patient satisfaction is the evaluative, emotional or affective response of the patient to the service provided by the health care provider and the expectation of the service. The satisfaction of each patient can be different depending on the expectations and reality obtained. This can be caused by several factors such as age, gender, occupation and education. This study was conducted to determine the relationship of these patient characteristics with the level of patient service satisfaction in the plastic facial and reconstructive surgery division of ENT department of Dr. M. Djamil hospital. This type of research is analytic research with cross sectional design. Respondents in this study were 37 people. Sampling was done using a purposive sampling method. This study used satisfaction questionnaires and medical record as an research instrument. The results showed that there were more subjects in the old adult age category (56.76%), female (51.35%), had a job (51.35%), had a high education (81.08%), and non PBI membership status (56,8%). The results of bivariate analysis showed that there was no relationship between age, sex, education and occupation with the level of satisfaction. P values obtained respectively p = 0.366, p = 0.692, p = 0.554 and p = 0.845. Whereas there are relationship between patient health assurance membership status with patient satisfaction by p values 0,033. Conclusion: that there is no relationship between patient characteristics with the level of service satisfaction in patients in the plastic facial and reconstructive surgery division in the ENT department of Dr. M. Djamil hospital except for health assurance membership status. Keywords: Education, Occupation, Health Assurance Membership Status, Satisfaction

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29

Doušová, Barbora, David Koloušek, Miloslav Lhotka, Martin Keppert, Martina Urbanová, Libor Kobera, and Jiří Brus. "Waste Brick Dust as Potential Sorbent of Lead and Cesium from Contaminated Water." Materials 12, no. 10 (May 20, 2019): 1647. http://dx.doi.org/10.3390/ma12101647.

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Adsorption properties of waste brick dust (WBD) were studied by the removing of PbII and CsI from an aqueous system. For adsorption experiments, 0.1 M and 0.5 M aqueous solutions of Cs+ and Pb2+ and two WBD (Libochovice—LB, and Tyn nad Vltavou—TN) in the fraction below 125 µm were used. The structural and surface properties of WBD were characterized by X-ray diffraction (XRD) in combination with solid-state nuclear magnetic resonance (NMR), supplemented by scanning electron microscopy (SEM), specific surface area (SBET), total pore volume and zero point of charge (pHZPC). LB was a more amorphous material showing a better adsorption condition than that of TN. The adsorption process indicated better results for Pb2+, due to the inner-sphere surface complexation in all Pb2+ systems, supported by the formation of insoluble Pb(OH)2 precipitation on the sorbent surface. A weak adsorption of Cs+ on WBD corresponded to the non-Langmuir adsorption run followed by the outer-sphere surface complexation. The leachability of Pb2+ from saturated WBDs varied from 0.001% to 0.3%, while in the case of Cs+, 4% to 12% of the initial amount was leached. Both LB and TN met the standards for PbII adsorption, yet completely failed for any CsI removal from water systems.

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Santos, Raimundo Nonato Viana, Luciana Lins Oliveira Santos, Luiz Junior Pereira Marques, Antônia Alice Costa Rodrigues, Maria José Pinheiro Correa, Mário Luiz Ribeiro Mesquita, and Maria Rosângela Malheiros Silva. "Influence of periods of coexistence of weeds on organic okra production." JANUARY 2021, no. 15(01):2021 (January 2, 2021): 41–47. http://dx.doi.org/10.21475/ajcs.21.15.01.2383.

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Weed management in okra grown in organic system minimizes crop yield losses. Thus, the objective of this study was to determine the period prior to weed interference in okra grown in organic system during the rainy and dry seasons in the state of Maranhão, northeastern Brazil. Experiments were conducted in the rainy and dry seasons in randomized block design with seven treatments and four replications. The treatments were T1 = weeds coexistence with okra for 7 days; T2 = coexistence for 14 days; T3 = coexistence for 21 days; T4 = coexistence for 28 days; T5 = coexistence for 35 days; T6 = coexistence for 42 days and, T7 = coexistence for 74 days). In addition to these treatments, we kept a control treatment with weed free until harvest to obtain maximum yield. At the end of each period of weed coexistence with the crop, three weed samples were collected in 0.25 m² to evaluate density, dry mass and to analise phytosociological parameters. The main weeds in both seasons were Commelina benghalensis, Cynodon dactylon, Eleusine indica, Alternanthera tenella and Amaranthus spinosus. The coexistence of weeds with the crop until harvest caused losses of 51% in the rainy season and 67% in the dry season compared to weed free control. In the rainy season, the period before weed interference (PBI) on okra crop of organic system was 12 days after emergence (DAE). In the dry season, 5% yield loss was observed 4 days after transplanting (DAT). Weed management in organic okra should be carried out earlier in the dry season than in the rainy season to avoid high yield losses

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Fan, Le-Qing, and Ji-Huai Wu. "NH4PbI3." Acta Crystallographica Section E Structure Reports Online 63, no. 11 (October 19, 2007): i189. http://dx.doi.org/10.1107/s1600536807050581.

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Single crystals of ammonium lead iodide, NH4PbI3, have been obtained by solid-state reactions. Each PbII ion is coordinated by six I− ions in a distorted octahedral environment. PbI6 octahedra are connected by common edges, forming a one-dimensional anion chain. All atoms except one H atom in a general position have site symmetry m.

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Moody, Philip W., Simon D. Speirs, Brendan J. Scott, and Sean D. Mason. "Soil phosphorus tests I: What soil phosphorus pools and processes do they measure?" Crop and Pasture Science 64, no. 5 (2013): 461. http://dx.doi.org/10.1071/cp13112.

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The phosphorus (P) status of 535 surface soils from all states of Australia was assessed using the following soil P tests: Colwell-P (0.5 m NaHCO3), Olsen-P (0.5 m NaHCO3), BSES-P (0.005 m H2SO4), and Mehlich 3-P (0.2 m CH3COOH + 0.25 m NH4NO3 + 0.015 m NH4F + 0.013 m HNO3 + 0.001 m EDTA). Results were correlated with soil P assays selected to estimate the following: soil solution P concentration (i.e. 0.01 m CaCl2 extractable P; Colwell-P/P buffer index); rate of P supply to the soil solution (i.e. P released to FeO-impregnated filter paper); sorbed P (i.e. Colwell-P); mineral P (i.e. fertiliser reaction products and/or soil P minerals estimated as BSES-P minus Colwell-P); the diffusive supply of P (i.e. P diffusing through a thin gel film, DGT-P); and P buffer capacity (i.e. single-point P buffer index corrected for Colwell-P, PBICol). Across all soils, Colwell-P and BSES-P were highly correlated with FeO-P (r = 0.76 and 0.58, respectively). Colwell-P was moderately correlated with mineral P (r = 0.24), but not solution P. Olsen-P and Mehlich-P were both highly correlated with FeO-P (r = 0.80 and 0.78, respectively) but, in contrast to Colwell-P and BSES-P, also showed moderate correlations with soil solution P (r = 0.29 and 0.34, respectively) and diffusive P supply (r = 0.31 and 0.49, respectively). Correlation coefficients with mineral P were r = 0.29 for Olsen-P and r = 0.17 for Mehlich-P. Soils were categorised according to their pH, clay activity ratio, content of mineral P and CaCO3 content, and the relationships between the empirical soil P tests examined for each soil category. Olsen-P and Colwell-P were correlated across all soil categories (r range 0.66–0.90), and a widely applicable linear equation was obtained for converting one soil test to the other. However, the correlations between other soil tests varied markedly between soil categories and it was not possible to develop such widely applicable conversion equations. Multiple step-up linear regressions were used to identify the key soil properties affecting soil solution P, P buffer capacity, and diffusive P supply, respectively. For all soil categories, solution P concentration (measured by CaCl2-P) increased as rate of P supply (measured as FeO-P) increased and P buffer capacity decreased. As an assay of sorbed P, Colwell-P alone did not significantly (P > 0.05) explain any of the variability in soil solution P, but when used in the index (Colwell-P/P buffer index), it was highly correlated (r = 0.74) with CaCl2-P. Soil P buffer capacity was dependent on different properties in different soil categories, with 45–65% of the variation in PBI accounted for by various combinations of Mehlich-Al, Mehlich-Fe, total organic C, clay content, clay activity ratio, and CaCO3 content, depending on soil category. The diffusive supply of P was primarily determined by rate of P supply (measured as FeO-P; r range 0.34–0.49), with significant (P < 0.05) small improvements due to the inclusion of PBICol and/or clay content, depending on soil category. For these surface soil samples, key properties of pH, clay activity ratio, clay content, and P buffer capacity varied so widely within individual Australian Soil Orders that soil classification was not useful for inferring intrinsic surface soil P properties such as P buffer capacity or the relationships between soil P tests.

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Wang, Long-Bai, Qiu-Yong Chen, Xue-Min Wu, Yong-Liang Che, Cheng-Yan Wang, Ru-Jing Chen, and Lun-Jiang Zhou. "Isolation of a Reassortant H1N2 Swine Flu Strain of Type “Swine-Human-Avian” and Its Genetic Variability Analysis." BioMed Research International 2018 (May 29, 2018): 1–10. http://dx.doi.org/10.1155/2018/1096079.

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We isolated an influenza strain named A/Swine/Fujian/F1/2010 (H1N2) from a pig suspected to be infected with swine flu. The results of electron microscopy, hemagglutination (HA) assay, hemagglutination inhibition (HI) assay, and whole genome sequencing analysis suggest that it was a reassortant virus of swine (H1N1 subtype), human (H3N2 subtype), and avian influenza viruses. To further study the genetic evolution of A/Swine/Fujian/F1/2010 (H1N2), we cloned its whole genome fragments using RT-PCR and performed phylogenetic analysis on the eight genes. As a result, the nucleotide sequences of HA, NA, PB1, PA, PB2, NP, M, and NS gene are similar to those of A/Swine/Shanghai/1/2007(H1N2) with identity of 98.9%, 98.9%, 99.0%, 98.6%, 99.0%, 98.9%, 99.3%, and 99.3%, respectively. Similar to A/Swine/Shanghai/1/2007(H1N2), we inferred that the HA, NP, M, and NS gene fragments of A/Swine/Fujian/F1/2010 (H1N2) strain were derived from classical swine influenza H3N2 subtype, NA and PB1 were derived from human swine influenza H3N2 subtype, and PB2 and PA genes were derived from avian influenza virus. This further validates the role of swine as a “mixer” for influenza viruses.

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Costa, Reginaldo Brito da, Marcos Deon Vilela de Resende, Paulo de Souza Gonçalves, Lincoln Carlos Silva de Oliveira, Luís Carlos Vinhas Ítavo, and Raul Alffonso Rodrigues Roa. "Seleção simultânea para porte reduzido e alta produção de látex em seringueira." Bragantia 67, no. 3 (2008): 649–54. http://dx.doi.org/10.1590/s0006-87052008000300013.

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Os objetivos deste trabalho foram avaliar a variabilidade genética e a possibilidade de sucesso na seleção simultânea para porte baixo e alta produção de látex considerando as variáveis relacionais: produtividade de látex por unidade de altura (PBA) e produtividade de látex por área basal das plantas (PBB) como novos caracteres no melhoramento da seringueira (Hevea brasiliensis). A seleção baseada nas referidas variáveis permitem a identificação de novos materiais genéticos destinados a plantios adensados. Vinte e duas progênies de meios-irmãos foram estabelecidas no município de Votuporanga (SP), sob delineamento de blocos ao acaso com 22 tratamentos, cinco repetições e dez plantas por parcela, no espaçamento de 3 x 2 m em linhas simples. Aos três anos de idade, as progênies foram avaliadas quanto aos caracteres em estudo. A combinação dos dois caracteres aumentou a variabilidade genética disponível para seleção sendo possível desenvolver eficiente melhoramento genético simultâneo para o aumento da produção de borracha e redução do porte da planta. Portanto, é possível melhorar os dois caracteres (PB e PBB) simultaneamente, não havendo prejuízo no caráter principal (PB). As altas correlações genéticas entre PBB e PBA (0,842) e entre PBB e altura (-0,578) revelam que a seleção baseada em PBB resultará em redução da altura. O tipo de seleção foi eficiente em aumentar a produção de borracha, reduzindo substancialmente a altura e pouco o perímetro do caule. Esses efeitos são desejáveis em um programa de melhoramento da seringueira visando à seleção de genótipos para plantios adensados.

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Siidra, O. I., D. Yu Zenko, A. N. Suknotova, and S. V. Krivovichev. "Crystal structure of a novel synthetic compound, Pb2O(OH)I, and structure refinement of ‘iodolaurionite’, Pb(OH)I: hydroxo- and oxocentred units in Pb minerals and synthetic compounds." Mineralogical Magazine 77, no. 8 (December 2013): 3239–48. http://dx.doi.org/10.1180/minmag.2013.077.8.14.

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AbstractYellow needles of 'iodolaurionite', Pb(OH)I, and a novel compound Pb2O(OH)I, have been prepared by hydrothermal reactions of PbO and PbI2 at 170°C. The crystal structure of 'iodolaurionite', Pb(OH)I (orthorhombic, Pnma, a = 7.8244(8), b = 4.2107(4), c = 10.4724(10) Å, V = 345.03(6) Å3, Z = 4) has been refined to R1 = 0.041 for 129 independent observed reflections. The structure is based on the OHPb3 triangles sharing common edges to produce single [OHPb]+ chains extending along the b axis and parallel to the ab plane. The three-dimensional integrity of the structure is provided by the Pb–I bonds and the O–H···I hydrogen bonding. The structure is isotypic with that of laurionite, Pb(OH)Cl. The crystal structure of Pb2O(OH)I (monoclinic, C2/m, a = 13.711(3), b = 4.0975(10), c = 9.584(2) Å, β = 110.64(1)°, V = 503.9(2) Å3, Z = 4), has been solved by direct methods and refined to R1 = 0.053 for 586 independent observed reflections. In the structure of Pb2O(OH)I, O(1)Pb4 tetrahedra link together by sharing edges and corners to form [OPb2]2+ chains similar to those observed in sidpietersite. The O(2) atoms belong to hydroxyl groups attached to both sides of the chains to produce novel [O(OH)Pb2]+ 1D units. The [O(OH)Pb2]+ units are extended parallel to the b axis and lie within the bc plane. The [O(OH)Pb2]+ units are linked together via hydrogen bonding in the (100) plane and by weak Pb–I bonds in the [100] direction. The [O(OH)Pb2]+ bands can be obtained from the [OPb] layer of OPb4 tetrahedra present in the structure of tetragonal PbO (litharge). The continuous [OPb] layer has to be broken into [O2Pb2] bands containing 3- and 4-coordinated O atoms in the 1:1 ratio with subsequent protonation of the 3-coordinated O sites. Relations of Pb(OH)I and Pb2O(OH)I to known Pb hydroxy- and oxyhalides are described briefly.

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Wasilenko, Jamie L., Chang Won Lee, Luciana Sarmento, Erica Spackman, Darrell R. Kapczynski, David L. Suarez, and Mary J. Pantin-Jackwood. "NP, PB1, and PB2 Viral Genes Contribute to Altered Replication of H5N1 Avian Influenza Viruses in Chickens." Journal of Virology 82, no. 9 (February 27, 2008): 4544–53. http://dx.doi.org/10.1128/jvi.02642-07.

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ABSTRACT The virulence determinants for highly pathogenic avian influenza viruses (AIVs) are considered multigenic, although the best characterized virulence factor is the hemagglutinin (HA) cleavage site. The capability of influenza viruses to reassort gene segments is one potential way for new viruses to emerge with different virulence characteristics. To evaluate the role of other gene segments in virulence, we used reverse genetics to generate two H5N1 recombinant viruses with differing pathogenicity in chickens. Single-gene reassortants were used to determine which viral genes contribute to the altered virulence. Exchange of the PB1, PB2, and NP genes impacted replication of the reassortant viruses while also affecting the expression of specific host genes. Disruption of the parental virus' functional polymerase complexes by exchanging PB1 or PB2 genes decreased viral replication in tissues and consequently the pathogenicity of the viruses. In contrast, exchanging the NP gene greatly increased viral replication and expanded tissue tropism, thus resulting in decreased mean death times. Infection with the NP reassortant virus also resulted in the upregulation of gamma interferon and inducible nitric oxide synthase gene expression. In addition to the impact of PB1, PB2, and NP on viral replication, the HA, NS, and M genes also contributed to the pathogenesis of the reassortant viruses. While the pathogenesis of AIVs in chickens is clearly dependent on the interaction of multiple gene products, we have shown that single-gene reassortment events are sufficient to alter the virulence of AIVs in chickens.

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Kawaguchi, Atsushi, Tadasuke Naito, and Kyosuke Nagata. "Involvement of Influenza Virus PA Subunit in Assembly of Functional RNA Polymerase Complexes." Journal of Virology 79, no. 2 (January 15, 2005): 732–44. http://dx.doi.org/10.1128/jvi.79.2.732-744.2005.

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ABSTRACT The RNA-dependent RNA polymerase of influenza virus consists of three subunits, PB1, PB2, and PA, and synthesizes three kinds of viral RNAs, vRNA, cRNA, and mRNA. PB1 is a catalytic subunit; PB2 recognizes the cap structure for generation of the primer for transcription; and PA is thought to be involved in viral RNA replication. However, the process of polymerase complex assembly and the exact nature of polymerase complexes involved in synthesis of the three different RNA species are not yet clear. ts53 virus is a temperature-sensitive (ts) mutant derived from A/WSN/33 (A. Sugiura, M. Ueda, K. Tobita, and C. Enomoto, Virology 65:363-373, 1975). We confirmed that the mRNA synthesis level of ts53 remains unaffected at the nonpermissive temperature, whereas vRNA synthesis is largely reduced. Sequencing of the gene encoding ts53 PA and recombinant virus rescue experiments revealed that an amino acid change from Leu to Pro at amino acid position 226 is causative of temperature sensitivity. By glycerol density gradient analyses of nuclear extracts prepared from wild-type virus-infected cells, we found that polymerase proteins sediment in three fractions: one (H fraction) consists of RNP complexes, another (M fraction) contains active polymerases but not viral RNA, and the other (L fraction) contains inactive forms of polymerases. Pulse-chase experiments showed that polymerases in the L fraction are converted to those in the M fraction. In ts53-infected cells, polymerases accumulated in the L fraction. These results strongly suggest that PA is involved in the assembly of functional viral RNA polymerase complexes from their inactive intermediates.

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Sharma, Kush, and Davinder Kumar Garg. "m-Associate PBIB designs using Youden-m squares." Communications in Statistics - Theory and Methods 47, no. 7 (September 27, 2017): 1653–62. http://dx.doi.org/10.1080/03610926.2017.1324990.

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Guo, Huihui, Yijie Fan, Haixia Guo, Jianfei Wu, Xiaoman Yu, Junmei Wei, Xin Lian, et al. "Somatic embryogenesis critical initiation stage‐specific m CHH hypomethylation reveals epigenetic basis underlying embryogenic redifferentiation in cotton." Plant Biotechnology Journal 18, no. 8 (January 30, 2020): 1648–50. http://dx.doi.org/10.1111/pbi.13336.

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Xing, Libo, Dong Zhang, Caiping Zhao, Youmei Li, Juanjuan Ma, Na An, and Mingyu Han. "Shoot bending promotes flower bud formation by mi RNA ‐mediated regulation in apple ( M alus domestica B orkh.)." Plant Biotechnology Journal 14, no. 2 (July 2, 2015): 749–70. http://dx.doi.org/10.1111/pbi.12425.

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Williams, Graham D., Amelia K. Pinto, Brittany Doll, and Adrianus C. M. Boon. "A North American H7N3 Influenza Virus Supports Reassortment with 2009 Pandemic H1N1 and Induces Disease in Mice without Prior Adaptation." Journal of Virology 90, no. 9 (March 2, 2016): 4796–806. http://dx.doi.org/10.1128/jvi.02761-15.

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ABSTRACTReassortment between H5 or H9 subtype avian and mammalian influenza A viruses (IAV) can generate a novel virus that causes disease and transmits between mammals. Such information is currently not available for H7 subtype viruses. We evaluated the ability of a low-pathogenicity North American avian H7N3 virus (A/shorebird/Delaware/22/2006) to reassort with mammalian or avian viruses using a plasmid-based competition assay. In addition to genome segments derived from an avian H7N9 virus, the H7N3 virus reassorted efficiently with the PB2, NA, and M segments from the 2009 pandemic H1N1 (PH1N1) virus.In vitroandin vivoevaluation of the H7N3:PH1N1 (7 + 1) reassortant viruses revealed that the PB2, NA, or M segments fromPH1N1 largely do not attenuate the H7N3 virus, whereas the PB1, PA, NP, or NS genome segments fromPH1N1 do. Additionally, we assessed the functionality of the H7N3:PH1N1 7 + 1 reassortant viruses by measuring the inflammatory responsein vivo. We found that infection with wild-type H7N3 resulted in increased inflammatory cytokine production relative to that seen with thePH1N1 strain and that the increase was further exacerbated by substitution ofPH1N1 PB2 but not NA or M. Finally, we assessed if any adaptations occurred in the individually substituted segments afterin vivoinoculation and found no mutations, suggesting thatPH1N1 PB2, NA, and M are genetically stable in the background of this H7N3 virus. Taking the data together, we demonstrate that a North American avian H7N3 IAV is genetically and functionally compatible with multiple gene segments from the 2009 pandemic influenza virus strain without prior adaptation.IMPORTANCEThe 2009 pandemic H1N1 virus continues to circulate and reassort with other influenza viruses, creating novel viruses with increased replication and transmission potential in humans. Previous studies have found that this virus can also reassort with H5N1 and H9N2 avian influenza viruses. We now show that several genome segments of the 2009 H1N1 virus are also highly compatible with a low-pathogenicity avian H7N3 virus and that these reassortant viruses are stable and not attenuated in an animal model. These results highlight the potential for reassortment of H1N1 viruses with avian influenza virus and emphasize the need for continued surveillance of influenza viruses in areas of cocirculation between avian, human, and swine viruses.

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Teh, Audrey Y‐H, Daniel Maresch, Katja Klein, and Julian K‐C Ma. "Characterization of VRC 01, a potent and broadly neutralizing anti‐ HIV m A b, produced in transiently and stably transformed tobacco." Plant Biotechnology Journal 12, no. 3 (November 21, 2013): 300–311. http://dx.doi.org/10.1111/pbi.12137.

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Kuo, Rei-Lin, and Robert M. Krug. "Influenza A Virus Polymerase Is an Integral Component of the CPSF30-NS1A Protein Complex in Infected Cells." Journal of Virology 83, no. 4 (December 3, 2008): 1611–16. http://dx.doi.org/10.1128/jvi.01491-08.

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ABSTRACT The NS1A protein of influenza A virus binds the cellular CPSF30 protein, thereby inhibiting the 3′-end processing of all cellular pre-mRNAs, including beta interferon pre-mRNA. X-ray crystallography identified the CPSF30-binding pocket on the influenza virus A/Udorn/72 (Ud) NS1A protein and the critical role of two hydrophobic NS1A amino acids outside the pocket, F103 and M106, in stabilizing the CPSF30-NS1A complex. Although the NS1A protein of the 1997 H5N1 influenza A/Hong Kong/483/97 (HK97) virus contains L (not F) at position 103 and I (not M) at position 106, it binds CPSF30 in vivo to a significant extent because cognate (HK97) internal proteins stabilize the CPSF30-NS1A complex in infected cells. Here we show that the cognate HK97 polymerase complex, containing the viral polymerase proteins (PB1, PB2, and PA) and the nucleocapsid protein (NP), is responsible for this stabilization. The noncognate Ud polymerase complex cannot carry out this stabilization, but it can stabilize CPSF30 binding to a mutated (F103L M106I) cognate Ud NS1A protein. These results suggested that the viral polymerase complex is an integral component of the CPSF30-NS1A protein complex in infected cells even when the cognate NS1A protein contains F103 and M106, and we show that this is indeed the case. Finally, we show that cognate PA protein and NP, but not cognate PB1 and PB2 proteins, are required for stabilizing the CPSF30-NS1A complex, indicating that the NS1A protein interacts primarily with its cognate PA protein and NP in a complex that includes the cellular CPSF30 protein.

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Nelson, Martha I., Susan E. Detmer, David E. Wentworth, Yi Tan, Aaron Schwartzbard, Rebecca A. Halpin, Timothy B. Stockwell, et al. "Genomic reassortment of influenza A virus in North American swine, 1998–2011." Journal of General Virology 93, no. 12 (December 1, 2012): 2584–89. http://dx.doi.org/10.1099/vir.0.045930-0.

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Revealing the frequency and determinants of reassortment among RNA genome segments is fundamental to understanding basic aspects of the biology and evolution of the influenza virus. To estimate the extent of genomic reassortment in influenza viruses circulating in North American swine, we performed a phylogenetic analysis of 139 whole-genome viral sequences sampled during 1998–2011 and representing seven antigenically distinct viral lineages. The highest amounts of reassortment were detected between the H3 and the internal gene segments (PB2, PB1, PA, NP, M and NS), while the lowest reassortment frequencies were observed among the H1γ, H1pdm and neuraminidase segments, particularly N1. Less reassortment was observed among specific haemagglutinin–neuraminidase combinations that were more prevalent in swine, suggesting that some genome constellations may be evolutionarily more stable.

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Azuma, Masaki, Hajime Hojo, Kengo Oka, Hajime Yamamoto, Keisuke Shimizu, Kei Shigematsu, and Yuki Sakai. "Functional Transition Metal Perovskite Oxides with 6s2 Lone Pair Activity Stabilized by High-Pressure Synthesis." Annual Review of Materials Research 51, no. 1 (July 26, 2021): 329–49. http://dx.doi.org/10.1146/annurev-matsci-080819-011831.

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Perovskite ABO3 oxides that have Bi and Pb at the A site and transition metals at the B site, when stabilized by high-pressure synthesis at several gigapascals, provide a rich parameter space of fascinating properties. Stereochemical 6 s2 lone pairs of Bi3+ and Pb2+ induce polar or antipolar distortions. 6 s2 and 6 s0 (Bi5+ and Pb4+) charge degree of freedom enable intermetallic charge transfer transitions. The structural distortion and the charge degree of freedom are coupled with magnetism of transition metals, resulting in various functionalities. In particular, we highlight magnetization reversal by electric field and polarization rotation in BiFe1− xCo xO3, negative thermal expansion in modified BiNiO3 and PbVO3, and systematic charge distribution changes in Pb MO3 ( M = 3 d transition metal).

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Gou, Jiqing, Smriti Debnath, Liang Sun, Amy Flanagan, Yuhong Tang, Qingzhen Jiang, Jiangqi Wen, and Zeng-Yu Wang. "From model to crop: functional characterization of SPL8 in M. truncatula led to genetic improvement of biomass yield and abiotic stress tolerance in alfalfa." Plant Biotechnology Journal 16, no. 4 (October 17, 2017): 951–62. http://dx.doi.org/10.1111/pbi.12841.

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Erdoğmuş, E., and İ. Pekgözlü. "Photoluminescence Properties of CaAlBO4:M (M: Pb2+, Dy3+, and Sm3+)." Journal of Applied Spectroscopy 81, no. 3 (July 2014): 394–98. http://dx.doi.org/10.1007/s10812-014-9943-4.

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48

Tomsig, J. L., and J. B. Suszkiw. "Pb2(+)-induced secretion from bovine chromaffin cells: fura-2 as a probe for Pb2+." American Journal of Physiology-Cell Physiology 259, no. 5 (November 1, 1990): C762—C768. http://dx.doi.org/10.1152/ajpcell.1990.259.5.c762.

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The effect of Pb2+ on catecholamine release was studied in isolated intact and permeabilized bovine chromaffin cells. Fura-2 was used to monitor intracellular Pb2+. A characterization of Pb2(+)-fura-2 interactions in solutions simulating intracellular ionic composition showed that Pb2+ forms a 1:1 Pb2(+)-fura-2 complex (apparent dissociation constant = 4.2 x 10(-12) M, pH 7.05) whose fluorescence resembles that of the Ca2(+)-fura-2 complex. Spectra recorded from fura-2-loaded cells indicate entry of Pb2+ into the cells. Intracellular Pb2+ concentrations were proportional to extracellular Pb2+ concentrations and were found to be 10(-11)-10(-12) M in cells exposed to micromolar Pb2+ concentrations. Pb2+ elicited the release of tritiated norepinephrine from fura-2-loaded cells, indicating the extraordinary effectiveness of Pb2+ as a releasing agent. Permeabilization of cells with digitonin showed that Pb2+ is able, in the absence of Ca2+, to produce exocytotic release at concentrations of 3.2 x 10(-10) M or higher (3 orders of magnitude lower than Ca2+). These results support the notion that Pb2+ can act as a potent Ca2+ surrogate in triggering secretion.

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POLARSKI, D. "CLASSICALITY OF PRIMORDIAL FLUCTUATIONS AND PRIMORDIAL BLACK HOLES." International Journal of Modern Physics D 10, no. 06 (December 2001): 927–34. http://dx.doi.org/10.1142/s021827180100161x.

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The production of Primordial Black Holes (PBH) from inflationary perturbations provides a physical process where the effective classicality of the fluctuations does not hold for certain scales. For adiabatic perturbations produced during inflation, this range of scales corresponds to PBH with masses M≪1015 g. For PBH with masses M ~ M H (te), the horizon mass at the end of inflation, the generation process during the preheating stage could be classical as well, in contrast to the formation of PBH on these scales by adiabatic inflationary perturbations. For the nonevaporated PBH, the generation process is essentially classical.

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Kolitsch, U., and D. Holtstam. "Barysilite from Garpenberg Norra, Dalarna, Sweden: occurrence and crystal structure refinement." Mineralogical Magazine 66, no. 2 (April 2002): 353–63. http://dx.doi.org/10.1180/0026461026620034.

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AbstractA new occurrence of barysilite, Pb8Mn(Si2O7)3, at the polymetallic Garpenberg Norra Zn-Pb deposit, Hedemora, Dalarna, Sweden, is described. The mineral, which forms colourless, transparent grains, is characterized by X-ray diffraction and electron-microprobe analyses. The assemblage includes tephroite, zincian jacobsite, manganoan diopside and others. The crystal structure of a barysilite crystal from Garpenberg Norra was redetermined using single-crystal X-ray diffraction data (Mo-Kα, CCD area detector) and has been refined in space group R3̄c with a = 9.804(1), c = 38.416(8)Å, V = 3197.8(8)Å3, to R1 = 2.32% for 1025 ‘observed’ reflections with Fo >4σ(Fo). A previous, low-precision structure determination (Lajzérowicz, 1965; R = 20%) is confirmed but improved considerably. The structure contains one distorted MnO6 polyhedron with six equivalent Mn–O bonds (2.224 Å), one Si2O7 disilicate unit with an Si–O–Si angle of 120.9°, and two non-equivalent Pb sites. The Pb1 site has a highly irregular, one-sided coordination with six O ligands, indicating a stereoactive 6s2 lone-electron pair on the Pb2+ ion, whereas the [6+3]-coordinated Pb2 site is fairly regular, with Pb–O distances of 2.540 (3×), 2.674 (3×) and 3.098 (3×) Å. The Pb2 site contains ~10% of Ca (+Ba) replacing Pb, corresponding to the structural formula Pb16(Pb,Ca)22Mn(Si2O7)3. This is the first direct proof that not only the M site in barysilite-type Pb8M(Si2O7)3 compounds can be replaced by divalent cations.

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Journal articles on the topic 'M-PBI'

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