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Manipulation of bicarbonate concentration in sperm capacitation media improves in vitro fertilisation output in porcine species

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Journal of Animal Science and Biotechnology 2019年第2期10卷 375-389页

作者： Cristina Soriano-úbeda jon romero-aguirregomezcorta Carmen Matás Pablo E.Visconti Francisco A.García-Vázquez Department of Physiology Faculty of Veterinary ScienceInternational Excellence Campus for Higher Education and Research“Campus Mare Nostrum”University of Murcia30100 MurciaSpain Institute for Biomedical Research of Murcia(IMIB-Arrixaca) MurciaSpain Department of Physiology Faculty of Medicine and NursingUniversity of the Basque Country UPV/EHULeioaBizkaiaSpain.4Department of Veterinary and Animal SciencesUniversity of MassachusettsAmherstMAUSA.

Background: The in vivo concentration of bicarbonate(HCO3-), one of the essential sperm capacitating effectors,varies greatly in the different environments sperm go through from cauda epididymis to the fertilisation site. On the contrary, porcine in vitro sperm capacitation and fertilisation media usually contains a standard concentration of25 mmol/L, and one of the main problems presented is the unacceptable high incidence of polyspermy. This work hypothesised that by modifying the HCO3-concentration of the medium, the output of in vitro sperm capacitation and fertilisation could be ***: Once exposed to the capacitation medium, the intracellular pH(pHi) of spermatozoa increased immediately even at low concentrations of HCO3-, but only extracellular concentrations of and above 15 mmol/L increased the substrates protein kinase A phosphorylation(pPKAs). Although with a significant delay, 15 mmol/L of HCO3-stimulated sperm linear motility and increased other late events in capacitation such as tyrosine phosphorylation(Tyr-P) to levels similar to those obtained with 25 mmol/L. This information allowed the establishment of a new in vitro fertilisation(IVF)system based on the optimization of HCO3-concentration to 15 mmol/L, which led to a 25.3% increment of the viable zygotes(8.6% in the standard system vs. 33.9%).Conclusions: Optimising HCO3-concentrations allows for establishing an IVF method that significantly reduced porcine polyspermy and increased the production of viable zygotes. A concentration of 15 mmol/L of HCO3-in the medium is sufficient to trigger the in vitro sperm capacitation and increase the fertilisation efficiency in porcine.

关键词： Adcy10 Boar Monospermy PKA

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The importance of post-COVID condition phenotypes characterization to decipher the mechanisms underlying this post-viral syndrome

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World Journal of Pediatrics 2024年第6期20卷 633-634页

作者： jon Izquierdo-Pujol Sara Moron-Lopez IrsiCaixa and Institute for Health Science Research Germans Trias i Pujol(IGTP) Can Ruti CampusBadalonaSpain Biomedicine doctoral programme Faculty of BiologyUniversity of BarcelonaBarcelonaSpain CIBERINFEC MadridSpain

The coronavirus disease-19(COVID-19)outbreak,caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),was declared a global pandemic in March *** has affected over 700 million people worldwide and resulted in almost 7 million deaths,equating to a 1%mortality *** present,the majority of COVID-19 cases are either asymptomatic or mild,typically resolving within two ***,between 1%and 10%of COVID-19 survivors do not fully recover and experience a post-viral syndrome referred to as"long COVID","post-acute COVID-19 syndrome"(PASC),or"post-COVID condition"(PCC).This post-viral syndrome affects both adult and pediatric ***,most of the studies published to date evaluate the adult population,leaving a gap in our understanding of its impact on children and adolescents.

关键词： acute mortality respiratory

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High-temperature tribological performance of functionally graded Stellite 6/WC metal matrix composite coatings manufactured by laser-directed energy deposition

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Friction 2024年第3期12卷 522-538页

作者： Marta OSTOLAZA Alaitz ZABALA jon Inaki ARRIZUBIETA Iñigo LLAVORI Nagore OTEGI Aitzol LAMIKIZ Department of Mechanical Engineering University of the Basque Country UPV/EHUPlaza Torres Quevedo 1Bilbo 48013Spain Faculty of Engineering Mechanics and Industrial ProductionMondragon UnibertsitateaLoramendi 4Mondragon 20500Spain

Wear-driven tool failure is one of the main hurdles in the *** issue can be addressed through surface coating with ceramic-reinforced metal matrix ***,the maximum ceramic content is limited by *** this work,the tribological behaviour of the functionally graded WC-ceramic-particlereinforced Stellite 6 coatings is *** that end,the wear resistance at room temperature and 400°C is ***,the tribological analysis is supported by crack sensitivity and hardness evaluation,which is of utmost importance in the processing of composite materials with *** indicate that functionally graded materials can be employed to increase the maximum admissible WC content,hence improving the tribological behaviour,most notably at high ***,a shift from abrasive to oxidative wear is observed in high-temperature wear testing.

关键词： friction coating metal matrix composite functionally graded materials high temperature laserdirected energy deposition

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Implications for brainstem recovery from studies in primates after sensory loss from arm

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Neural Regeneration Research 2024年第3期19卷 479-480页

作者： Jamie L.Reed Hui-Xin Qi jon H.Kaas Department of Psychology Vanderbilt UniversityNashvilleTNUSA

For decades,researchers have known that when neurons lose their activating inputs,they can atrophy and even *** example,removing sensory nerve inputs from the arm to the spinal cord after amputation or cutting the spinal nerves can shrink the post-synaptic target zones(e.g.,Woods et al.,2000).From touch receptors for the hand and arm,primary nerve afferents enter the spinal cord,and axons travel in the dorsal columns to target the cuneate nucleus(Cu)of the brainstem on the same side of the body(Figure 1).When sensory loss is unilateral,the overwhelming result is for the associated primary target zone to shrink in total size(cross-sectional area),as compared to the size of the opposite side.

关键词： brainstem shrink removing

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Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems

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Journal of Mountain Science 2024年第1期21卷 33-48页

作者： Francis Levi A.DURANO jon Marx SARMIENTO Larry N.DIGAL Pedro A.ALVIOLA IV School of Management University of the Philippines MindanaoDavao City 8000Philippines

Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation

关键词： Cocoa farms Cobb-Douglas production function Elevation Philippines Stochastic frontier analysis Technical efficiency

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Enhancement of the CO_(2)adsorption and hydrogenation to CH_(4)capacity of Ru–Na–Ca/γ–Al_(2)O_(3)dual function material by controlling the Ru calcination atmosphere

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Journal of Environmental Sciences 2024年第6期140卷 292-305页

作者： Alejandro Bermejo-López Beñat Pereda-Ayo jon A.Onrubia-Calvo JoséA.González-Marcos Juan R.González-Velasco Department of Chemical Engineering Faculty of Science and TechnologyUniversidad del País Vasco UPV/EHUBarrio Sarrienas/n48940 LeioaBizkaiaSpain

Integrated CO_(2)capture and utilization(ICCU)technology requires dual functional materials(DFMs)to carry out the process in a single reaction *** influence of the calcination atmosphere on efficiency of 4%Ru-8%Na_(2)CO_(3)-8%CaO/γ-Al_(2)O_(3)DFM is *** adsorbent precursors are first co-impregnated onto alumina and calcined in ***,Ru precursor is impregnated and four aliquotes are subjected to different calcination protocols:static air in muffle or under different mixtures(10%H_(2)/N_(2),50%H_(2)/N_(2)and N_(2))*** are characterized by XRD,N_(2)adsorption-desorption,H_(2)chemisorption,TEM,XPS,H_(2)-TPD,H_(2)-TPR,CO_(2)-TPD and *** catalytic behavior is evaluated,in cycles of CO_(2)adsorption and hydrogenation to CH_(4),and temporal evolution of reactants and products concentrations is *** calcination atmosphere influences the physicochemical properties and,ultimately,activity of *** data and catalytic performance discover the acccomodation of Ru nanoparticles disposition and basic sites is mostly influencing the catalytic *** calcined under N_(2)flow(RuNaCa-N_(2))shows the highest CH_(4)production(449μmol/g at 370℃),because a well-controlled decomposition of precursors which favors the better accomodation of adsorbent and Ru phases,maximizing the specific surface area,the Ru-basic sites interface and the participation of different basic sites in the CO_(2)methanation ***,the calcination in a N_(2)flow is revealed as the optimal calcination protocol to achieve highly efficient DFM for integrated CO_(2)adsorption and hydrogenation applications.

关键词： CO_(2)methanation Integrated CO_(2)capture and utilization(ICCU) Dual functional material(DFM) Ru calcination atmosphere

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CHARTING TTHE ROAD AHEAD

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Beijing Review 2024年第31期67卷 18-19页

作者： jon Taylor University of Texas at San Antonio

The Communist Party of China(CPC)recently concluded the long-anticipated Third Plenary Session of the 20th CPC Central *** meeting brought together the Party's top leadership to discuss and articulate China's policy g... 详细信息

关键词： policy goals strategic

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Are gender inclusiveness and rural transformation interlinked?The case of Bangladesh

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Journal of Integrative Agriculture 2024年第6期23卷 2112-2126页

作者： Maria Fay Rola-Rubzen Mohammad Jahangir Alam jon Marx Sarmiento Ismat Ara Begum Al Amin Al Abbasi Subrata Saha UWA School of Agriculture and Environment The University of Western AustraliaPerth 6009Australia Department of Agribusiness and Marketing Bangladesh Agricultural UniversityMymensingh-2202Bangladesh Department of Agricultural Economics Bangladesh Agricultural UniversityMymensingh-2202Bangladesh

Gender inclusiveness is important in the rural transformation process of Bangladesh as rural women play key roles in both agricultural and non-agricultural *** inclusiveness also leads to gender *** empirically evaluate relationships between rural transformation and gender inclusiveness in *** consider three rural transformation indicators:high-value commodities’share in agricultural output values,non-farm employment’s share in rural labor employment,and non-agricultural GDP’s share in total *** capturing gender inclusiveness include the per capita rural income of males and females,ratio of investments into gender programs,female access to education,access to healthcare,employment participation,land ownership,and asset *** test the effect of the difference in per capita rural income of males and females and the ratio of their incomes and check for the robustness of the gender variables across different model *** 128 district-level observations from 32 districts of Bangladesh across four time periods(2000,2005,2010 and 2016),we use both ordinary least squares and fixed effects panel regression *** find that female land and asset ownership and access to education and healthcare are robust determinants of various stages of rural ***,our results suggest that improving women’s ownership of land and assets and investing in women’s education and healthcare will likely contribute to a more inclusive rural transformation.

关键词： rural transformation Bangladesh gender inclusiveness investments on women

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两种富含甘氨酸的RNA结合蛋白参与选择性剪接实现对水稻耐热性的昼夜节律调控

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Science Bulletin 2024年第1期69卷 59-71页

作者：杨闯罗安妮芦海平 Seth jon Davis 刘建祥 State Key Laboratory of Plant Environmental Resilience College of Life SciencesZhejiang UniversityHangzhou 310027China Department of Biology University of YorkYork YO105DDUK

Rice(Oryza sativa L.)production is threatened by global warming associated with extreme high temperatures,and rice heat sensitivity is differed when stress occurs between daytime and ***,the underlying molecular mechanism are largely *** show here that two glycine-rich RNA binding proteins,Os GRP3 and Os GRP162,are required for thermotolerance in rice,especially at *** rhythmic expression of Os GRP3/Os GRP162 peaks at midnight,and at these coincident times,is increased by heat *** is largely dependent on the evening complex component Os *** next found that the double mutant of Os GRP3/Os GRP162 is strikingly more sensitive to heat stress in terms of survival rate and seed setting rate when comparing to the wild-type ***,the defect in thermotolerance is more evident when heat stress occurred in nighttime than that in *** heat stress,the double mutant of Os GRP3/Os GRP162 displays globally reduced expression of heat-stress responsive genes,and increases of m RNA alternative splicing dominated by *** study thus reveals the important role of Os GRP3/Os GRP162 in thermotolerance in rice,and unravels the mechanism on how Os GRP3/Os GRP162 regulate thermotolerance in a diurnal manner.

关键词： Alternative splicing Diurnal regulation Glycine-rich protein Oryza sativa L. Thermotolerance

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Investigation of Hexavalent Chromium Reduction in Strong Saline and Acidic Nitro-Phosphate Solutions

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Journal of Analytical Sciences, Methods and Instrumentation 2024年第1期14卷 1-13页

作者： Deniz Avsar Niels Højmark Andersen Dag Øistein Eriksen jon Petter Omtvedt Department of Chemistry University of Oslo Oslo Norway

Phosphorus fertilizers from less pure sedimentary sources become increasingly important, due to depletion of phosphorus from igneous rock of high quality. Consequently, robust methods with potential to remove various types of hazardous elements are required. Among such impurities, hexavalent chromium (Cr(VI)) is very likely to become a future challenge. Different industrial ways to treat phosphate rock are currently being practised, and we have here studied how chromium behaves when using the nitro-phosphate process. The reduction mechanism of Cr (VI) in nitric acid and phosphoric acid solutions was investigated by measuring redox potential and UV-VIS spectra. The results show that Cr (VI) is not stable in strong nitric acid solutions. Reduction of Cr (VI) species decreased with decreasing temperature, NO2 concentration, ionic strength and absence of light. These findings support the proposed reduction reaction:The reduction rate was observed proportional to the nitric acid decomposition: .

关键词： Nitro-Phosphate Fertilizers Chromium (VI) Reduction Chromium Speciation Ultraviolet-Visible Spectroscopy

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