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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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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

作者： Cristina Soriano-Úbeda jon romero-aguirregomezcorta Carmen Matás Pablo E.Visconti Francisco Department of Physiology， Faculty of Veterinary Science， International Excellence Campus for Higher Education and Research "Campus Mare Nostrum"， University of Murcia Institute for Biomedical Research of Murcia (IMIB-Arrixaca) Department of Physiology，Faculty of Medicine and Nursing， University of the Basque Country UPV EHU Department of Veterinary and Animal Sciences，University of Massachusetts，Amherst， MA， USA

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Influence of in vitro capacitation time on structural and functional human sperm parameters

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Asian Journal of Andrology 2020年第5期22卷 447-453页

作者： Paula Saez-Espinosa Natalia Huerta-Retamal Laura Robles-Gomez Manuel Aviles jon Aizpurua Irene Velasco Alejandro romero Maria Jose Gomez-Torres Department of Biotechnology Faculty of ScienceUniversity of AlicanteAlicante 03080Spain FISABI0-University Hospital of San Juan de Alicante Service of Gynecology and ObstetricsSan Juan de Alicante 03550Spain Departm ent of Cell Biology and Histology Faculty of MedicineUniversity of Murcia and IMIB-ArrixacaMurcia 30100Spain IVF Spain Reproductive MedicineAlicante 03540Spain University Hospital of San Juan de Alicante Service of Gynecology and ObstetricsSan Juan de Alicante 03550Spain Human Fertility Cathedra University of AlicanteAlicante 03080Spain.

A cascade of dramatic physiological events is linked to the sperm acrosome reaction and binding to the oocyte's zona pellucida during human sperm ***,structural and functional sperm changes during capacitation currently remain poorly ***,we performed a multibiomarker approach based on the utilization of sperm concentration,motility,viability,morphology,acrosome reaction,tyrosine phosphorylation,DNA fragmentation,and lectin-binding sites to analyze the impact caused by swim-up selection times(uncapacitated,1 h capacitated,and 4 h capacitated)on sperm function and structure in normozoospermic *** found that a 4 h swim-up capacitation increased sperm quality,because a large number of cells with normal morphology and lower DNA fragmentation rates were ***,the long-term capacitation induced a higher percentage of cells with tyrosine phosphorylation of the principal piece as well as a redistribution of lectin-binding ***,the multivariate biomarkers analyzed showed a less variable distribution on spermatozoa recovered after 4 h capacitation than that with the shorter capacitation *** findings stress the importance of capacitation time as a relevant factor in sperm quality with potential biological reproductive implications both for basic research and in assisted reproduction techniques.

关键词： acrosome reaction capacitation DNA fragmentation glycocalyx lectin-binding sites membrane integrity protein phosphorylation sperm selection

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Multiscale assessment of ground,aerial and satellite spectral data for monitoring wheat grain nitrogen content

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Information Processing in Agriculture 2023年第4期10卷 504-522页

作者： Joel Segarra Fatima Zahra Rezzouk Nieves Aparicio jon González-Torralba Iker Aranjuelo Adrian Gracia-romero Jose Luis Araus Shawn C.Kefauver Integrative Crop Ecophysiology Group Plant Physiology SectionFaculty of BiologyUniversity of BarcelonaBarcelona 08028Spain AGROTECNIO(Center for Research in Agrotechnology) Lleida 251981Spain Agro-technological Institute of Castilla y León(ITACyL) Valladolid 47071Spain Grupo AN Tajonar 31192NavarreSpain Instituto de Agrobiotecnología(IdAB) CSIC-Gobierno de NavarraMutilva Baja 31192PamplonaNavarreSpain

Wheat grain quality characteristics have experienced increasing attention as a central factor affecting wheat end-use products quality and human ***,in the last decades a reduction in grain quality has been ***,it is central to develop efficient quality-related phenotyping *** this sense,one of the most relevant wheat features related to grain quality traits is grain nitrogen content,which is directly linked to grain protein content and monitorable with remote sensing ***,the relation between nitrogen fertilization and grain nitrogen content(protein)plays a central role in the sustainability of *** aiming to develop efficient phenotyping tools using remote sensing instruments and to advance towards a field-level efficient and sustainable monitoring of grain nitrogen status,this paper studies the efficacy of various sensors,multispectral and visible red-greenblue(RGB),at different scales,ground and unmanned aerial vehicle(UAV),and phenological stages(anthesis and grain filling)to estimate grain nitrogen *** models were calculated using vegetation indices at each sensing level,sensor type and phenological ***,this study explores the up-scalability of the best performing model to satellite level Sentinel-2 equivalent *** found that models built at the phenological stage of anthesis with UAV-level multispectral cameras using red-edge bands outperformed grain nitrogen content estimation(R2=0.42,RMSE=0.18%)in comparison with those models built with RGB imagery at ground and aerial level,as well as with those built with widely used ground-level multispectral *** also demonstrated the possibility to use UAV-built multispectral linear models at the satellite scale to determine grain nitrogen content effectively(R2=0.40,RMSE=0.29%)at actual wheat fields.

关键词： Wheat Remote sensing Sentinel-2 Grain nitrogen content Phenotyping

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Combining in-situ water quality and remotely sensed data across spatial and temporal scales to measure variability in wet season chlorophyll-a:Great Barrier Reef lagoon(Queensland,Australia)

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Ecological Processes 2013年第1期2卷 328-349页

作者： Michelle J Devlin Eduardo Teixeira da Silva Caroline Petus Amelia Wenger Daniel Zeh Dieter Tracey Jorge GÁlvarez-romero jon Brodie Catchment to Reef Research Group TropWaterJames Cook UniversityTownsvilleQLD4811Australia Australian Research Council Centre of Excellence for Coral Reef Studies James Cook UniversityTownsvilleQLDAustralia School of Marine and Tropical Biology James Cook UniversityTownsvilleQLDAustralia

Introduction:Combining in-situ data from single-point time series with remotely sensed spatial data allowed a greater elucidation of changes in chlorophyll-a concentrations through wet season conditions in the Great Barrier Reef coastal ***:Single-point time-series data were collected from 2006 to 2012 during high river flow conditions to assess changes in phytoplankton biomass(measured as chlorophyll-a).Additionally,three flood plume water types,derived from classified true-colour Aqua moderate resolution imaging spectroradiometer(MODIS)images,were used to group single-point time-series data for the phytoplankton biomass ***:Survey data illustrate the heterogeneity of chlorophyll-a distribution over seasonal and inter-annual cycles and the difficulty in describing community responses through the wet *** spatial data demonstrate distinct regional differences throughout the Great Barrier *** high chlorophyll-a concentrations measured in flood plume waters immediately adjacent to the inshore,highly turbid‘inner’flood plume are a product of sufficient light,given most of the suspended solids have settled from the plume,and the availability of sufficient nutrients,which drive higher phytoplankton production and characterise the formation of secondary stage flood *** formation and extent of these secondary flood plumes were mapped using MODIS true-colour satellite *** distance and the location of the secondary plume water are reliant on flow,coastal hydrodynamics,and biological ***:The combination of in-situ data and remotely sensed data provides information on the complexity of these coastal processes during the wet season and offers managers a more comprehensive understanding of the extent of nutrient enrichment in the Great Barrier Reef coastal area and the potential influence of flood plumes on coastal marine ecosystems.

关键词： Chlorophyll-a Great barrier reef Phytoplankton Monitoring Remote sensing MODIS

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On the rate of convergence of the maximum likelihood estimator of a k-monotone density

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Science China Mathematics 2009年第7期52卷 1525-1538页

作者： WELLNER jon A Department of Statistics University of Washington

Bounds for the bracketing entropy of the classes of bounded k-monotone functions on [0,A] are obtained under both the Hellinger distance and the Lp(Q) distance,where 1 p < ∞ and Q is a probability measure on [0,A].The result is then applied to obtain the rate of convergence of the maximum likelihood estimator of a k-monotone density.

关键词： bracketing metric entropy maximum likelihood estimator Hellinger distance 62G05 46B50

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Varieties for Cohomology with Twisted Coefficients

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Acta Mathematica Sinica,English Series 1999年第1期15卷 81-92页

作者： jon F.Carlson Department of Mathemtics University of GeorgiaAthensGA 30602 USA

Let G be a finite group and k a field of characteristic p>*** this paper we consider the support variety for the cohomology module ExtkG*（M,N） where M and N are *** is the subvariety of the maximal ideal spectrum of H*（G,k） of the annihilator of the cohomology module. For modules in the principal block we show that that the variety is contained in the intersections of the varieties of M and N and the difference between the that intersection and the support variety of the cohomology module is contained in the group theoretic *** other blocks a new nucleus is defined and a similar theorem is *** in the case of modules in a nonprincipal block several new difficulties are highlighted by some examples.

关键词： Group Cohomology Support varieties Cohomological varieties Annihilators of cohomology

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Phenotypic plasticity of labile traits in the wild

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Current Zoology 2013年第4期59卷 485-505页

作者： jon E. BROMMER Department of Biology University Hill 20014 University of Turku Finland ARONIA Research and Development Institute Novia Applied University and Abo Akademi University Raseborgsvaigen 9 10600 Ekenas Finland

Individual-based studies allow quantification ofphenotypic plasticity in behavioural, life-history and other labile traits The study of phenotypic plasticity in the wild can shed new light on the ultimate objectives （1） whether plasticity itself can evolve or is constrained by its genetic architecture, and （2） whether plasticity is associated to other traits, including fitness （selection）. I describe the main statistical approach for how repeated records of individuals and a description of the environment （E） allow quantification of variation in plasticity across individuals （IxE） and genotypes （GxE） in wild populations. Based on a literature review of life-history and behavioural studies on plasticity in the wild, I discuss the present state of the two objectives listed above. Few studies have quantified GxE of labile traits in wild populations, and it is likely that power to detect statistically sig- nificant GxE is lacking. Apart from the issue of whether it is heritable, plasticity tends to correlate with average trait expression （not fully supported by the few genetic estimates available） and may thus be evolutionary constrained in this way. Individ- ual-specific estimates of plasticity tend to be related to other traits of the individual （including fitness）, but these analyses may be anti-conservative because they predominantly concern stats-on-stats. Despite the increased interest in plasticity in wild popula- tions, the putative lack of power to detect GxE in such populations hinders achieving general insights. I discuss possible steps to invigorate the field by moving away from simply testing for presence of GxE to analyses that ＇scale up＇ to population level proce-sses and by the development of new behavioural theory to identify quantitative genetic parameters which can be estimated

关键词： Individual-level plasticity Life history Animal personality Linear mixed model Animal model Wild population Longitudinal study

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No trade-off between trichome production and tolerance to leaf and inflorescence damage in a natural population of Arabidopsis lyrata

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Journal of Plant Ecology 2014年第4期7卷 373-383页

作者： Adriana Puentes jonÅgren Department of Plant Ecology and Evolution Evolutionary Biology Centre(EBC)Uppsala UniversityNorbyvägen 18DSE-75236 UppsalaSweden

Aims Early models of plant defense conceived resistance and tolerance to herbivore damage as mutually exclusive *** for this idea has been equivocal and studies on these two strategies are still needed to understand the evolution of defenses in natural *** Arabidopsis lyrata,the production of trichomes,a documented resistance trait,has been associated with a fitness cost in the absence of *** examined whether trichome production is also associated with reduced tolerance to simulated herbivore *** We conducted a field experiment in a natural swedish population of *** where we inflicted leaf(0 vs.50%of the area of each leaf removed)and inflorescence damage(0 vs.50%of inflores-cences removed)to trichome-producing and glabrous plants in a factorial *** examined the response(survival,growth and reproduction)of the plants to the imposed damage over 2 *** Findingstrichome-producing plants were not less tolerant than glabrous plants to simulated herbivore damage(no significant morph×leaf damage or morph×inflorescence damage interactions).Inflorescence and leaf damage had independent negative effects on the performance of damaged *** damage reduced rosette size the year of damage,but effects on reproductive output in the year of damage,and on survival and reproductive performance the following year were weak and not statistically *** damage significantly reduced the number of flowers,fruits and seeds the year of damage,but not in the following *** of morph,the study population was more tolerant to leaf than to inflorescence *** results indicated no trade-off between trichome production and tolerance,suggesting that these two defense mechanisms have the potential to evolve indepen-dently in this *** population.

关键词： plant defense fitness costs resistance traits defoliation florivory

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Some paradoxical observations about spheroidal graphite degeneracy

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China Foundry 2018年第6期15卷 457-463页

作者： Jacques Lacaze jon Sertucha CIRIMAT Université de ToulouseBP 44362F-31030ToulouseFrance Investigaeiòn y Desarrollo de Procesos Metalúrgicos IK4-AzterlanAliendalde auzunea 6E-48200Durango(Bizkaia)Spain

Differential thermal analysis experiments have been performed on samples machined from Y2-blocks cast with different high-silicon spheroidal graphite irons. Depending on magnesium, silicon, cerium and antimony content, the as-cast microstructure showed various levels of chunky graphite in the central part of the blocks. In contrast, the microstructure of the materials after remelting and resolidification during differential thermal analysis consisted of lamellar or compacted graphite. The formation of chunky graphite in the as-cast microstructure is rationalized using an index or silicon equivalent that has been recently suggested. The differences in the microstructures after differential thermal analysis are discussed in terms of available free magnesium. Emphasis is finally put on the striking differences in characteristic size of the microstructures made of compacted graphite as compared to lamellar graphite and chunky graphite. This leads to tentative conclusions about growth of compacted and chunky graphite which would be worthy of further experimental investigations.

关键词： high-silicon spheroidal graphite iron graphite degeneracy compacted graphite chunky graphite

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