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Chromatin condensation but not DNA integrity of pig sperm is greater in the sperm-rich fraction

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Journal of Animal Science and Biotechnology 2024年第1期15卷 171-181页

作者： Estel Viñolas-Vergés jordi Ribas-Maynou Isabel Barranco Camila Peres Rubio Sergi Bonet jordi Roca Marc Yeste Unit of Cell Biology Department of BiologyFaculty of SciencesUniversity of GironaGironaSpain Biotechnology of Animal and Human Reproduction(TechnoSperm) Institute of Food and Agricultural TechnologyUniversity of GironaGironaSpain Department of Medicine and Animal Surgery Faculty of Veterinary ScienceUniversity of MurciaMurciaSpain Catalan Institution for Research and Advanced Studies(ICREA) S08010 BarcelonaSpain

Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo *** some mammals,like pigs,ejaculates are emitted in three separate fractions:pre-sperm,sperm-rich(SRF)and post sperm-rich(PSRF).These fractions are known to vary in volume,sperm concentration and quality,as well as in the origin and composition of seminal plasma(SP),with differences being also observed within the SRF ***,whether disparities in the DNA integrity and chromatin condensation and pro-tamination of their sperm exist has not been *** This study determined chromatin protamination(Chromomycin A3 test,CMA_(3)),condensation(Dibromobi-mane test,DBB),and DNA integrity(Comet assay)in the pig sperm contained in the first 10 m L of the SRF(SRF-P1),the remaining portion of the sperm-rich fraction(SRF-P2),and the post sperm-rich fraction(PSRF).While chromatin protamination was found to be similar between the different ejaculate fractions(P>0.05),chromatin condensation was seen to be greater in SRF-P1 and SRF-P2 than in the PSRF(P=0.018 and P=0.004,respectively).Regarding DNA integrity,no differences between fractions were observed(P>0.05).As the SRF-P1 has the highest sperm concentra-tion and ejaculate fractions are known to differ in antioxidant composition,the oxidative stress index(OSi)in SP,calcu-lated as total oxidant activity divided by total antioxidant capacity,was tested and confirmed to be higher in the SRF-P1 than in SRF-P2 and PSRF(0.42±0.06 vs.0.23±0.09 and 0.08±0.00,respectively;P<0.01);this index,in addition,was observed to be correlated to the sperm concentration of each fraction(Rs=0.973;P<0.001).Conclusion While sperm DNA integrity was not found to differ between ejaculate fractions,SRF-P1 and SRF-P2 were observed to exhibit greater chromatin condensation than the *** could be related to the OSi of each fraction.

关键词： Chromatin Condensation DNA integrity Ejaculate fractions Pig Protamination Sperm

Developing kNN forest data imputation for Catalonia

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Journal of Forestry Research 2024年第4期35卷 142-155页

作者： Timo Pukkala Núria Aquilué Ariadna Just jordi Corbera Antoni Trasobares Forest Science and Technology Centre of Catalonia(CTFC) Crta.de St.Llorençde MorunysKm 225280 SolsonaSpain Cartographic and Geological Institute of Catalonia(ICGC) 08038 BarcelonaSpain

The combined use of LiDAR(Light Detection And Ranging)scanning and field inventories can provide spatially continuous wall-to-wall information on forest *** information can be used in many ways in forest mapping,scenario analyses,and forest manage-ment *** study aimed to find the optimal way to obtain continuous forest data for Catalonia when using kNN imputation(kNN stands for“k nearest neighbors”).In this method,data are imputed to a certain location from k field-measured sample plots,which are the most similar to the location in terms of LiDAR metrics and topographic *** multidimensional Euclidean distance was used as the similarity *** study tested two different methods to optimize the distance *** first method optimized,in the first step,the set of LiDAR and topographic variables used in the measure,as well as the transformations of these *** weights of the selected variables were optimized in the second *** other method optimized the variable set as well as their transformations and weights in one single *** two-step method that first finds the variables and their transfor-mations and subsequently optimizes their weights resulted in the best imputation *** the study area,the use of three to five nearest neighbors was *** and latitude turned out to be the most important variables when assessing the similarity of two locations of Catalan forests in the context of kNN data *** optimal distance measure always included both LiDAR metrics and topographic *** study showed that the optimal similarity measure may be different for different ***,it was suggested that kNN data imputation should always be started with the optimization of the measure that is used to select the k nearest neighbors.

关键词： Forest inventory Differential evolution Simulated annealing LiDAR

Latest Updates and Challenges in infections in intensive care medicine

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Journal of Intensive Medicine 2024年第1期4卷 1-2页

作者： jordi Rello Global Health eCore Vall d’Hebron University Hospital Campus08035 BarcelonaSpain Medicine Department Universitat Internacional de CatalunyaSant Cugat del VallesSpain

In a rapidly changing world,the role of intensive care has become increasingly *** care medicine was born during the polio pandemic nearly 50 years ago and the COVID-19 pandemic has stringed its *** this issue,a distinguished selection of the world’s leading experts will address some of the most intriguing issues,sharing their insights and experience in a collection of original articles,narrative reviews,and systematic reviews focusing on hot topics in intensive care units(ICU).Developing and tropical countries have particularities that need to be ***,dengue,and causes of unknown origin fever in this setting are detailed in three articles in the current issue.

关键词： visibility string insight

Bias-Free Solar-to-Hydrogen Conversion in a BiVO4/PM6:Y6 Compact Tandem with Optically Balanced Light Absorption

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Energy & Environmental Materials 2024年第4期7卷 231-238页

作者： Catarina G.Ferreira Constanza Sansierra Francisco Bernal-Texca Mingyu Zhang Carles Ros jordi Martorell ICFO–Institut de Ciències Fotòniques The Barcelona Institute of Science and Technology Departament de Física Universitat Politècnica de Catalunya

The high voltage required to overcome the thermodynamic threshold and the complicated kinetics of the water splitting reaction limit the efficiency of single semiconductor-based photoelectrochemistry.A semiconductor/solar cell tandem structure has been theoretically demonstrated as a viable path to achieve an efficient direct transformation of sunlight into chemical energy.

关键词： bismuth vanadate compact tandem organic solar cells photonic multilayers solar-to-hydrogen conversion

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原子生态学:原子与生态的耦合

Science Bulletin 2024年第1期69卷 11-16页

作者： jordi Sardans Josep Penuelas CSIC Global Ecology Unit Centre for Ecological Research and Forestry Applications(CREAF)-CSIC-Universitat Autònoma de Barcelona(UAB)Barcelona 08193Spain CREAF Barcelona 08193Spain

The functional roles of molecules in organisms and ecosystems are driven by the atoms that form them,including their threedimensional form,bond polarity,size,and *** advances in environmental and ecological sciences,such as ecological stoichiometry,ionomics,biochemistry,biogeochemical-niche studies,and omic ecological approaches,have provided substantial data and results that support the associations of the elements/atoms in organisms and ecosystems with their fundamental functioning and structure in nature.

关键词： polarity elements structure

Genetically-and environmentally-dependent processes drive interspecific and intraspecific divergence in the Chinese relict endemic genus Dipteronia

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Plant Diversity 2024年第5期46卷 585-599页

作者： Tao Zhou Xiaodan Chen jordi López-Pujol Guoqing Bai Sonia Herrando-Moraira Neus Nualart Xiao Zhang Yuemei Zhao Guifang Zhao Key Laboratory of Resource Biology and Biotechnology in Western China(Ministry of Education) College of Life SciencesNorthwest UniversityXi'an 710069China School of Pharmacy Xi'an Jiaotong UniversityXi'an 710061China College of Life Science Shanxi Normal UniversityTaiyuanChina Botanic Institute of Barcelona(IBB) CSIC-CMCNBBarcelona 08038CataloniaSpain Escuela de Ciencias Ambientales Universidad Espíritu Santo(UEES)Samborondón 091650Ecuador Shaanxi Engineering Research Centre for Conservation and Utilization of Botanical Resources Xi'an Botanical Garden of Shaanxi ProvinceXi'an 710061China School of Biological Sciences Guizhou Education UniversityGuiyangChina

China is a hotspot of relict plant species that were once widespread throughout the Northern *** research has demonstrated that the occurrence of long-term stable refugia in the mountainous regions of central and south-western China allowed their persistence through the late Neogene climate *** of these relict lineages is Dipteronia,an oligotypic tree genus with a fossil record extending to the ***,we investigated the genetic variability,demographic dynamics and diversification patterns of the two currently recognized Dipteronia species(Dipteronia sinensis and ***).Molecular data were obtained from 45 populations of Dipteronia by genotyping three cpDNA regions,two single copy nuclear genes and 15 simple sequence repeat *** genetic study was combined with niche comparison analyses on the environmental space,ecological niche modeling,and landscape connectivity *** found that the two Dipteronia species have highly diverged both in genetic and ecological *** the incipient speciation processes that can be observed in ***,the occurrence of long-term stable refugia and,particularly,a dispersal corridor along Daba Shan-west Qinling,likely ensured its genetic and ecological integrity to *** study will not only help us to understand how populations of Dipteronia species responded to the tectonic and climatic changes of the Cenozoic,but also provide insight into how Arcto-Tertiary relict plants in East Asia survived,evolved,and diversified.

关键词： Dipteronia Interspecific/intraspecific divergence Genetic structure Climatic niche divergence Dispersal corridor

Evolutionary history shapes variation of wood density of tree species across the world

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Plant Diversity 2024年第3期46卷 283-293页

作者： Fangbing Li Hong Qian jordi Sardans Dzhamal Y.Amishev Zixuan Wang Changyue Zhang Tonggui Wu Xiaoniu Xu Xiao Tao Xingzhao Huang Anhui Province Key Laboratory of Forest Resources and Silviculture Anhui Agricultural UniversityHefei 230036China State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA CREAF Cerdanyola del VallesBarcelona 08193Spain Global Ecology Unit CREAF-CSIC-UAB CSICBellaterraBarcelona 08193Spain Key Laboratory of Ecosystem Carbon Source and Sink China Meteorological Administration(ECSS-CMA)School of Applied MeteorologyNanjing University of Information Science&Technology219 Ningliu RoadNanjing 210044China Department of Natural Resources Management Lakehead UniversityThunder BayOntario P7B 5E1Canada School of Forestry&Landscape of Architecture Anhui Agricultural UniversityHefei 230036China Research Institute of Subtropical Forestry Chinese Academy of ForestryHangzhou 311400China

The effect of evolutionary history on wood density variation may play an important role in shaping variation in wood density,but this has largely not been *** a comprehensive global dataset including 27,297 measurements of wood density from 2621 tree species worldwide,we test the hypothesis that the legacy of evolutionary history plays an important role in driving the variation of wood density among tree *** assessed phylogenetic signal in different taxonomic(e.g.,angiosperms and gymnosperms)and ecological(e.g.,tropical,temperate,and boreal)groups of tree species,explored the biogeographical and phylogenetic patterns of wood density,and quantified the relative importance of current environmental factors(e.g.,climatic and soil variables)and evolutionary history(i.e.,phylogenetic relatedness among species and lineages)in driving global wood density *** found that wood density displayed a significant phylogenetic *** density differed among different biomes and climatic zones,with higher mean values of wood density in relatively drier regions(highest in subtropical desert).Our study revealed that at a global scale,for angiosperms and gymnosperms combined,phylogeny and species(representing the variance explained by taxonomy and not direct explained by long-term evolution process)explained 84.3%and 7.7%of total wood density variation,respectively,whereas current environment explained 2.7%of total wood density variation when phylogeny and species were taken into *** angiosperms and gymnosperms were considered separately,the three proportions of explained variation are,respectively,84.2%,7.5%and 6.7%for angiosperms,and 45.7%,21.3%and 18.6%for *** study shows that evolutionary history outpaced current environmental factors in shaping global variation in wood density.

关键词： Wood density Phylogeny Angiosperms Gymnosperms Climate factors Biophysical parameters

An unprotected vulnerable relict subtropical conifer-Keteleeria evelyniana: Its forests, populations, growth and endangerment by invasive alien plant species in China

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Plant Diversity 2024年第5期46卷 648-660页

作者： Cindy Q.Tang Min-Rui Du Huan-Chong Wang You-Cai Shi Jia-Le Zeng Shu-Li Xiao Peng-Bin Han Jian-Ran Wen Shi-Qian Yao Ming-Chun Peng Chong-Yun Wang Yong-Ping Li jordi López-Pujol Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityBuilding#3Guozhong DalouDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of Life Sciences Yunnan UniversityShengming Kexueyuan Building#2Chenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of Natural Resources Yunnan UniversityChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina Botanic Institute of Barcelona(IBB CSIC-CMCNC)Passeig del Migdia s/nBarcelona 08038CataloniaSpain Escuela de Ciencias Ambientales Universidad Espíritu Santo(UEES)Samborondon 091650Ecuador

Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien *** the crucial importance of understanding forest dynamics,knowledge gaps persist,particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria *** this study,we investigated the impact of invasive plants on the regeneration of forests dominated by ***,a subtropical relict species in southwestern *** this purpose,we characterized forest dynamics of 160 forest plots featuring *** as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of *** identified four distinct forest types in which *** was *** found that radial growth of *** trees is faster in younger ageclasses today than it was for older trees at the same *** population structure of *** in each forest type exhibited a multimodal age-class ***,three forest types lacked established saplings younger than 10 years old,a situation attributed to the dense coverage of the invasive alien Ageratina *** invasive species resulted in a reduction of understory species ***,our analysis uncovered a significant negative correlation in phylogenetic relatedness(net relatedness index)between native and invasive alien plant species in eastern *** suggests closely related invasive species face heightened competition,hindering successful *** together,our findings indicate that successful establishment and habitat restoration of *** seedling/saplings require effective measures to control invasive plants.

关键词： Keteleeria evelyniana Age structure Regeneration Species diversity Invasive alien species Phylogenetic relatedness

Analysis of an event study using the Fama–French five‑factor model:teaching approaches including spreadsheets and the R programming language

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Financial Innovation 2023年第1期9卷 2042-2075页

作者： Monica Martinez‑blasco Vanessa Serrano Francesc Prior jordi Cuadros IQS School of Management-Universitat Ramon Llull Via Augusta 39008017 BarcelonaSpain IQS School of Engineering-Universitat Ramon Llull Via Augusta 39008017 BarcelonaSpain

The current financial education framework has an increasing need to introduce tools that facilitate the application of theoretical models to real-world data and ***,only a limited number of free tools are available for this *** this lack of tools,the present study provides two approaches to facilitate the implementa-tion of an event *** first approach consists of a set of MS Excel files based on the Fama–French five-factor model,which allows the application of the event study methodology in a semi-automatic *** second approach is an open-source R-programmed tool through which results can be obtained in the context of an event study without the need for programming *** tool widens the calculus possibilities provided by the first approach and offers the option to apply not only the Fama–French five-factor model but also other models that are common in the finan-cial *** is a user-friendly tool that enables reproducibility of the analysis and ensures that the calculations are free of manipulation *** approaches are freely available and ready-to-use.

关键词： Event study Fama–French five-factor model Financial education Teaching innovation Spreadsheet R programming language