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

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

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基于等效框架模型的无筋砌体结构非线性模拟方法研究

基于等效框架模型的无筋砌体结构非线性模拟方法研究

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2024年工程结构抗震技术交流会

作者：桑笑晗 PERE roca 孔庆钊

等效框架模型是模拟砌体墙平面力学性能的一种宏观方法,砌体墙的墙柱和墙梁之间的连接区域视为刚体区域,同时墙柱和墙梁考虑了非线性弯曲变形与剪切变形。与文献中广泛使用的截面纤维模型不同,本文基于ANSYS软件采用了纵向弹簧模型与横... 详细信息

等效框架模型是模拟砌体墙平面力学性能的一种宏观方法,砌体墙的墙柱和墙梁之间的连接区域视为刚体区域,同时墙柱和墙梁考虑了非线性弯曲变形与剪切变形。与文献中广泛使用的截面纤维模型不同,本文基于ANSYS软件采用了纵向弹簧模型与横向弹簧模型来分别实现了弯曲行为与剪切行为的模拟。本文比较了两个开洞二层无筋砌体结构的非线性有限元分析结果和试验结果,同时与文献中采用截面纤维模型的有限元结果进行对比。对比的结果表明,在静力加载条件下模拟结果与试验结果吻合较好,同时此方法相较于截面纤维模型在后屈曲强度的模拟上具有更高的准确性。

关键词：无筋砌体等效框架模型弹簧单元力学性能 ANSYS软件

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Effects of the Pesticide <i>Furadan</i>on Traits Associated with Reproduction in Wild Potato Species

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American Journal of Plant Sciences 2012年第11期3卷 1608-1612页

作者： Alfonso del Rio John Bamberg Ruth Centeno-Diaz Alberto Salas william roca David Tay International Potato Center (CIP) Lima Peru International Potato Center (CIP) Lima Peru. USDA/Agriculture Research Service US Potato Genebank Wisconsin USA

Natural populations of wild potato species are the backups for the diversity held in genebanks for research and breeding. Some potato species are known to grow in close proximity to cultivated fields, thus are potentially impacted by human activity, including exposure to pesticides. The present study tested the effects of a common pesticide on reproductive traits of potatoes known to grow in or near pesticide-treated fields in central Peru. Furadan? 4F, an insecticide— nematicide (common name = carbofuran) was applied at two different rates to populations representing 15 wild potato species in a greenhouse environment in Peru. Flowering duration of these populations was usually significantly reduced in comparison to a water control, and in a few cases, percent viable pollen also was. These findings suggest that agrichemicals may be having unintentional effects on wild potato populations in ways that could compromise their genetic diversity.

关键词： Potato Species Pesticide Contamination Genetic Drift Reproductive Capacity

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An expandable chamber for safe brain retraction: new technologies in the field of transcranial endoscopic surgery

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2023年第4期24卷 326-335页

作者： Elena roca Anna GOBETTI Giovanna CORNACCHIA Oscar VIVALDI Barbara BUFFOLI Giorgio RAMORINO Head and Neck Department NeurosurgeryIstituto Ospedaliero Fondazione Poliambulanza25124 BresciaItaly Technology for Health PhD Program University of Brescia25124 BresciaItaly Materials Science and Technology at Department of Mechanical and Industrial Engineering University of Brescia25123 BresciaItaly Metallurgy at Department of Mechanical and Industrial Engineering University of Brescia25123 BresciaItaly Anatomy and Physiopathology Division Department of Clinical and Experimental SciencesUniversity of Brescia25123 BresciaItaly

Neurosurgery is a highly specialized field:it often involves surgical manipulation of noble structures and cerebral retraction is frequently necessary to reach deep-seated brain *** are still no reliable methods preventing possible retraction *** objective of this study was to design work chambers well suited for transcranial endoscopic surgery while providing safe retraction of the surrounding brain *** chamber is designed to be inserted close to the intracranial point of interest;once it is best placed it can be *** should guarantee an appreciable workspace similar to that of current neurosurgical *** experimental aspect of this study involved the use of a force sensor to evaluate the pressures exerted on the brain tissue during the retraction *** pterional craniotomy,pressure measurements were made during retraction with the use of a conventional metal spatula with different *** that,although the force values necessary for retraction and exerted on the spatula by the neurosurgeon are the same,the local pressure exerted on the parenchyma at the edge of the spatula at different inclinations varied greatly.A new method of cerebral retraction using a chamber retractor(CR)has been designed to avoid any type of complication due to spatula edge overpressures and to maintain acceptable pressure values exerted on the parenchyma.

关键词： Brain retraction Spatula Brain retractor design Brain retraction injury Retraction complication Transcranial endoscopic surgery

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Oxytocin in pig seminal plasma is positively related with in vivo fertility of inseminated sows

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Journal of Animal Science and Biotechnology 2022年第2期13卷 430-440页

作者： Lorena Padilla Marina López-Arjona Silvia Martinez-Subiela Heriberto Rodriguez-Martinez Jordi roca Isabel Barranco Department of Medicine and Animal Surgery Faculty of Veterinary MedicineUniversity of MurciaE-30100 MurciaSpain Department of Biomedical&Clinical Sciences(BKV) BKH/Obstetrics&GynaecologyFaculty of Medicine and Health SciencesLinköping UniversitySE-58185 LinköpingSweden Department of Veterinary Medical Sciences University of BolognaIT-40064 Ozzano dell’EmiliaBolognaItaly

Background:Identification of relevant in vivo biomarkers for fertility remains a challenge for the livestock *** of the small peptide hormone oxytocin(OXT),involved in male reproductive function and present in the seminal plasma(SP)of several species could be a robust *** study characterized concentrations of SPOXT in ejaculates from boars used in artificial insemination(AI)programs aiming to evaluate its relationship with sperm quality variables and in vivo fertility of their liquid-stored *** OXT concentrations(ng/mL)were measured in 169 ejaculates from 61 boars of the Duroc,Pietrain,Landrace and Large White breeds using a direct competitive immunoassay test based on AlphaLISA®***(ejaculate volume,sperm concentration,total sperm count)and sperm parameters(motility,viability,intracellular generation of reactive oxygen species,plasma membrane fluidity)were assessed at 0 h and 72 h in AI-semen samples stored at 17℃.In vivo fertility included only 18 Large White and Landrace boars whose AI-semen was used to inseminated>100 sows and evaluated both farrowing rate and litter size of 3,167 ***:The results showed that SP-OXT differed between boars and between ejaculates within boar(P<0.05)but not between breeds(Duroc,Pietrain,Landrace and Large White).Ejaculates with higher SP-OXT concentration/mL(hierarchically grouped;P<0.001)had larger volume and came from younger boars(P<0.05).Ejaculates of boars showing positive farrowing rate deviation exhibited higher(P<0.05)SP-OXT concentration/mL than those with negative farrowing rate ***:The SP concentrations of OXT are boar,ejaculate and age dependent,and positively related with ejaculate volume and farrowing rates of liquid-stored semen AI-doses.

关键词： Artificial insemination Ejaculate Fertility Oxytocin Pig Semen quality Seminal plasma

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Predicting the returns of the US real estate investment trust market:evidence from the group method of data handling neural network

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Financial Innovation 2023年第1期9卷 2668-2700页

作者： Wendi Zhang Bin Li Alan Wee‑Chung Liew Eduardo roca Tarlok Singh Department of Accounting Finance and EconomicsGriffith Business SchoolGriffith UniversityNathan CampusBrisbaneQLDAustralia Institute for Integrated and Intelligent Systems Griffith UniversityNathanBrisbaneQLDAustralia

Purpose:The Group Method of Data Handling(GMDH)neural network has demon-strated good performance in data mining,prediction,and *** have used it to forecast stock and real estate investment trust(REIT)returns in some coun-tries and region,but not in the United States(US)REIT *** primary goal of this study is to predict the US REIT market using GMDH and then compare its accuracy with that derived from the traditional prediction ***/methodology/approach:To forecast the return on the US REIT index,this study used the GMDH neural network and the generalized autoregressive conditional heteroscedasticity(GARCH)*** this test,the training samples,testing samples,and kernel functions of the GMDH model are controlled to investigate their impact on the accuracy of the machine learning *** experiments were performed using the GARCH model,and the accuracies of these two approaches were ***:Compared with GARCH,GMDH’s accuracy is much higher,indicating that the machine learning approach can provide a highly accurate prediction of REIT *** size of the training samples and the kernel functions in the GMDH model affect the accuracy of the prediction *** particular,the kernel function has a signifi-cant impact on prediction *** linear and linear covariance kernel functions are simple to train and yield accurate predictions,whereas the quadratic function is difficult to *** with small training samples,GMDH can outperform GARCH in prediction *** limitations/implications:Although GMDH shows good performance in predicting the US REIT return,it is still a black-box model,and the algorithm is difficult for financial analysts to develop and *** data used in this study come from the US REIT market,which is the world’s largest and most liquid *** implications:This research shows that the GMDH model outperforms the GARCH model in forecasting REIT ***,

关键词： REIT prediction Machine learning GMDH GARCH Accuracy

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Metabolomic fingerprinting of pig seminal plasma identifies in vivo fertility biomarkers

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Journal of Animal Science and Biotechnology 2022年第2期13卷 473-487页

作者： Yentel Mateo-Otero Pol Fernández-López Ariadna Delgado-Bermúdez Pau Nolis Jordi roca Jordi Miró Isabel Barranco Marc Yeste Biotechnology of Animal and Human Reproduction(TechnoSperm) Institute of Food and Agricultural TechnologyUniversity of GironaES-17003 GironaSpain Department of Biology Unit of Cell BiologyFaculty of SciencesUniversity of GironaES-17003 GironaSpain Centre d’Estudis Avançats de Blanes(CEAB) Spanish Research Council(CSIC)ES-17300 GironaSpain Magnetic Nuclear Resonance Facility Autonomous University of BarcelonaBellaterraES-08193 Cerdanyola del VallèsSpain Department of Animal Medicine and Surgery Faculty of Veterinary MedicineUniversity of MurciaES-30100 MurciaSpain Equine Reproduction Service Department of Animal Medicine and SurgeryFaculty of Veterinary MedicineAutonomous University of BarcelonaBellaterraES-08193 Cerdanyola del VallèsSpain Department of Veterinary Medical Sciences University of BolognaIT-40064 Ozzano dell’EmiliaBolognaItaly

Background:Metabolomic approaches,which include the study of low molecular weight molecules,are an emerging-omics technology useful for identification of *** this field,nuclear magnetic resonance(NMR)spectroscopy has already been used to uncover(in)fertility biomarkers in the seminal plasma(SP)of several mammalian ***,NMR studies profiling the porcine SP metabolome to uncover in vivo fertility biomarkers are yet to be carried ***,this study aimed to evaluate the putative relationship between SPmetabolites and in vivo fertility *** this end,24 entire ejaculates(three ejaculates per boar)were collected from artificial insemination(AI)-boars throughout a year(one ejaculate every 4 months).Immediately after collection,ejaculates were centrifuged to obtain SP-samples,which were stored for subsequent metabolomic analysis by NMR *** outcomes from 1525 inseminations were recorded over a year,including farrowing rate,litter size,stillbirths per litter and the duration of ***:A total of 24 metabolites were identified and quantified in all *** operating characteristic(ROC)curve analysis showed that lactate levels in SP had discriminative capacity for farrowing rate(area under the curve[AUC]=0.764)while carnitine(AUC=0.847),hypotaurine(AUC=0.819),sn-glycero-3-phosphocholine(AUC=0.833),glutamate(AUC=0.799)and glucose(AUC=0.750)showed it for litter ***,citrate(AUC=0.743),creatine(AUC=0.812),phenylalanine(AUC=0.750),tyrosine(AUC=0.753)and malonate(AUC=0.868)levels had discriminative capacity for stillbirths per litter;and malonate(AUC=0.767)and fumarate(AUC=0.868)levels for gestation ***:The assessment of selected SP-metabolites in ejaculates through NMR spectroscopy could be considered as a promising non-invasive tool to predict in vivo fertility outcomes in ***,supplementing AI-doses with specific metabolites should also be envisaged as a way to improve their f

关键词： Artificial insemination in vivo fertility Metabolomics NMR Pregnancy outcomes Seminal plasma

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Determining indoor air quality and identifying the origin of odour episodes in indoor environments

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Journal of Environmental Sciences 2009年第3期21卷 333-339页

作者： Eva Gallego Xavier roca Jose Francisco Perales Xavier Guardino Environmental Centre Laboratory Polytechnic University of Catalonia (LCMA-UPC) Avda Diagonal 647 E 08028 Barcelona Spain National Centre of Work Conditions (INSHT) Dulcet 2-10 E 08034 Barcelona Spain

A methodology for identifying volatile organic compounds （VOCs） and determining air quality of indoor air has been developed. The air samples are collected using pump samplers by the inhabitants when they perceive odorous and/or discomfort episodes. Glass multi-sorbent tubes are connected to the pump samplers for the retention of VOC. The analysis is performed by automatic thermal desorption （ATD） coupled with gas chromatography-mass spectrometry （GC/MS）. This methodology can be applied in cases of sick building syndrome （SBS） evaluation, in which building occupants experience a series of varied symptoms that appear to be linked to time spent in the building. Chemical pollutants concentrations （e.g., VOC） have been described to contribute to SBS. To exemplify the methodology, a qualitative determination and an evaluation of existing VOC were performed in a dwelling where the occupants experienced the SBS symptoms. Higher total VOC （TVOC） levels were detected during episodes in indoor air （1.33 ±1.53 mg/m^3） compared to outdoor air （0.71± 0.46 mg/m^3）. The concentrations of individual VOCs, such as ethanol, acetone, isopropanol, 1-butanol, acetic acid, acetonitrile and 1-methoxy-2-propanol, were also higher than the expected for a standard dwelling. The external source of VOC was found to be an undeclared activity of storage and manipulation of solvents located at the bottom of a contiguous building.

关键词： indoor air thermal desorption TVOC VOC sick building syndrome

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Urban agriculture in Kathmandu as a catalyst for the civic inclusion of migrants and the making of a greener city

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Frontiers of Architectural Research 2020年第1期9卷 169-190页

作者： Maurice Mitchell Amara roca lglesias CASS School of Art Architecture and DesignLondon Metropolitan UniversityUK

This research explores the opportunities offered for the creation of a green city on the recently secured Bagmati riverbanks in Kathmandu,which is subject to rapid inward migration from landless rural *** research asks what architectural theory and practice can contribute to this setting to support the fit between emergent bottom-up initiatives and topdown city *** this end,it deepens and extends loose fit theory,research methods,and reflective practices to investigate latent possibilities,assemble a narrative of embedded change,and create spatial imaginaries of topographical change on the Bagmati ***,it argues that architectural theory and practice can play a vital role in integrating migrants into civic institutions and helping generate a highly green city by making the relation-ships between setting and occupant explicit,stimulating and representing alternative imaginaries,and framing a civic discourse.

关键词： Architecture Urban agriculture Urban rivers Urban migrants Loose-fit city Kathmandu

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Juxtacrine interaction of macrophages and bone marrow stromal cells induce interleukin-6 signals and promote cell migration

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Bone Research 2015年第2期3卷 100-111页

作者： Jia Chang Amy J Koh Hernan roca Laurie K McCauley Department of Periodontics and Oral Medicine University of Michigan School of Dentistry Department of Periodontology University of Florida College of Dentistry Department of Pathology University of Michigan Medical School

The bone marrow contains a heterogeneous milieu of cells, including macrophages, which are key cellular mediators for resolving infection and inflammation. Macrophages are most well known for their ability to phagocytose foreign bodies or apoptotic cells to maintain homeostasis; however, little is known about their function in the bone microenvironment. In the current study, we investigated the in vitro interaction of murine macrophages and bone marrow stromal cells （BMSCs）, with focus on the juxtacrine induction of IL-6 signaling and the resultant effect on BMSC migration and growth. The juxtacrine interaction of primary mouse macrophages and BMSCs activated IL-6 signaling in the co-cultures, which subsequently enhanced BMSC migration and increased BMSC numbers. BMSCs and macrophages harvested from IL-6 knockout mice revealed that IL-6 signaling was essential for enhancement of BMSC migration and increased BMSC numbers via juxtacrine interactions. BMSCs were the main contributor of IL-6 signaling~ and hence activation of the IL-6/ gp130/STAT3 pathway. Meanwhile, macrophage derived IL-6 remained important for the overall production of IL-6 protein in the co-cultures. Taken together, these findings show the function of macmphages as co-inducers of migration and growth of BMSCs, which could directly influence bone formation and turnover.

关键词： BMSCs IL bone STAT cell

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