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Phylog.netic alpha and beta diversity in tropical tree assemblag.s along.reg.onalscale environmental g.adients in northwest South America

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Journal of Plant Ecolog. 2014年第2期7卷 145-153页

作者： Sebastián g.nzález-Caro María natalia Umaña Esteban Álvarez Pablo R.Stevenson Nathan g.Swenson Ecosystem Services&Climate Chang. Lab Botanical Garden of MedellínMedellínAntioquia 050001Colombia Department of Plant Biolog. Michigan State UniversityEast LansingMI 48824USA Department of Ecolog. Universidad de AlcaláAlcaláMadrid 28801Spain Department of Biolog.cal Sciences Universidad de Los AndesBogotá7495Colombia

Aims Environmental g.adients are drivers of species diversity;however,we know relatively little about the evolutionary processes underlying.these relationships.A potentially powerful approach to studying.diversity g.adients is to quantify the phylog.netic structure within and between assemblag.s arrayed along.broad spatial and environmental ***,we evaluate the phylog.netic structure of plant assemblag.s along.an environmental g.adient with the expectation that the habitat specialization of entire lineag.s is an important evolutionary pattern influencing.the structure of tree communities along.environmental *** We evaluated the effect of several environmental variables on the phylog.netic structure of plant assemblag.s in 145 plots distributed in northwestern South America that cover a broad environmental *** phylog.netic alpha diversity was quantified for each plot and the phylog.netic beta diversity between each pair of plots was also *** the alpha and beta diversity measures were then related to spatial and environmental g.adients in the study *** Finding. We found that g.adients in temperature and potential evapotranspiration have a strong.relationship with the phylog.netic alpha diversity in our study system,with phylog.netic overdispersion in low temperatures and phylog.netic clustering.at hig.er ***,the phylog.netic beta diversity between two plots increases with an increasing.difference in temperature,whereas annual precipitation was not a sig.ificant predictor of community phylog.netic *** also found that the phylog.netic structure of the plots in our study system was related to the deg.ee of seasonal flooding.and seasonality in *** particular,more stressful environments such as dry forests and flooded forests showed phylog.netic ***,in contrast with previous studies,we find that phylog.netic beta diversity was not strong.y related to the spatial d

关键词： phylog.netic conservatism habitat filtering immig.ation environmental g.adient

The mystery of molten metal

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China Foundry 2010年第4期7卷 425-437页

作者： natalia Sobczak Jerzy Sobczak Rajiv Asthana Robert Purg.rt Foundry Research Institute Department of Eng.neering.& Technolog. University of Wisconsin-Stout Energ. Industries of Ohio

Recent advances in scientific understanding.of hig.-temperature materials processing.using.novel experimental methodolog.es have shed lig.t on the complex role of surface and interface phenomena. New in-situ studies on molten metal/solid ceramic interactions using.a unique experimental complex at the Foundry Research Institute, Krakow, have revealed a number of unusual observations in materials processing.at hig. temperatures. We present some such unusual observations and their explanation with reference to liquid metal processing.of Al, Ni, and Ti, and their alloys in contact with oxide ceramics. In particular, we focus on the following.aspects: primary oxidation of Al from residual water vapor or oxyg.n, capillary purification to remove surface oxide, substrate protection by CVD carbon, roug.ening.due to spinel whisker formation, inclusions in casting. due to mechanical detachment, floatation due to buoyancy forces, and seg.eg.tion due to directional solidifciation, modification of the solid surface morpholog. by metal vapor ahead of the liquid, and the complication due to multi-component alloys melted in crucibles made from complex oxide-based ceramics. In the case of Ti, rapid reactions with oxides result in undesirable volumetric chang.s that create difficulty in casting.hig.-quality Ti parts, particularly by investment casting. Nanoscale (e.g., colloidal) coating. based on Y2O3 protect crucibles and hold ladles ag.inst such attack. Practical insig.ts and recommendations for materials processing.emerg.ng.from the fundamental studies on hig.-temperature interfacial phenomena have been described.

关键词： molten metal hig.-temperature phenomena in-situ observation casting.defects

Facile synthesis of nanosized sodium mag.esium hydride,NaMg.3

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Prog.ess in Natural Science:Materials International 2013年第3期23卷 343-350页

作者： Hazel Reardon natalia Mazur Duncan H.g.eg.ry WestCHEM School of ChemistryJoseph Black BuildingUniversity of GlasgowGlasgow G12 8QQ ScotlandUK Department of Materials Science and Eng.neering Norwegian University of Science and TechnologyN-7491 TrondheimNorway

The ternary mag.esium hydride NaMg. 3 has been synthesised via reactive milling.*** method employed neither a reactive H2 atmosphere nor hig. pressure sintering.or other post-treatment *** formation of the ternary hydride was studied as a function of milling.time and ball:powder *** purity NaMg. 3 powder(orthorhombic space g.oup Pnma,a 5.437(2),b 7.705(5),c 5.477(2) ;Z 4) was prepared in 5 h at hig. ball:powder ratios and characterised by powder X-ray diffraction(PXD),Raman spectroscopy and scanning.electron microscopy/energ. dispersive X-ray spectroscopy(SEM/EDX).The products formed sub-micron scale(typically 200-400 nm in size) crystallites that were approximately isotropic in *** dehydrog.nation behaviour of the ternary hydride was investig.ted by temperature prog.ammed desorption(TPD).The nanostructured hydride releases hydrog.n in two steps with an onset temperature for the first step of 513 K.

关键词： Hydride Mechanochemistry Structure Hydrog.n storag. Raman

Sustained activation of P2X7 induces MMP-2- evoked cleavag. and functional purinoceptor inhibition

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Journal of Molecular Cell Biolog. 2018年第3期10卷 229-242页

作者： Christopher N. J. Young.natalia Chira Justyna Róg.Rasha Al-Khalidi Mag.lie Benard Ludovic g.las Philippe Chan David Vaudry Krzysztof Zablocki Dariusz C. g.recki School of Allied Health Sciences Faculty of Health and Life Sciences De Montfort University Leicester LE1 5RR UK Molecular Medicine Laboratory Institute of Biomedical and Biomolecular Sciences School of Pharmacy and Biomedical Sciences University of Portsmouth Portsmouth PO1 2DT UK Laboratory of Cellular Metabolism Department of Biochemistry Nencki Institute of Experimental Biology of the Polish Academy of Sciences Pasteur Str. 02- 093 Warsaw Poland PRIMACEN Cell Imaging Platform of Normandy Inserm IBiSA and PISSARO Proteomic Platform Institute for Research and Innovation in Biomedicine University of Rouen 76821 Mont-Saint-Aignan France

P2X7 purinoceptor promotes survival or cytotoxicity depending.on extraceUular adenosine triphosphate （ATP） stimulus Intensity controlling.its ion channel or P2X7-dependent larg. pore （LP） functions. Mechanisms g.verning.this operational diverg.nce and functional idiosyncrasy are ill-understood. We have discovered a feedback loop where sustained activation of P2X7 trig.ers release of active matrix metalloproteinase 2 （MMP-2）, which halts ion channel and LP responses via the MMP-2-dependent receptor cleavag.. This mechanism operates in cells as diverse as macrophag.s, dystrophic myoblasts, P2X7-transfected HEK293, and human tumour cells. g.ven that serum-born MMP-2 activity also blocked receptor functions, P2X7 responses in vivo may decrease in org.ns with permeable capillaries. Therefore, this mechanism represents an Important fine-tuning.of P2X7 functions, reliant on both cell-autonomous and extraneous factors. Indeed, it allowed evasion from the ATP-induced cvtotoxicity in macrophag.s and human cancer ceils with hig. P2X7 expression levels. Finally, we demonstrate that P2X7 ablation eliminated g.tatinase activity in inflamed dystrophic muscles in vivo. Thus, P2X7 antag.nists could be used as an alternative to hig.ly toxic MMP inhibitors in treatments of inflammatory diseases and cancers.

关键词： P2X7 MMP-2 DMD macrophag. β-dystrog.ycan CD44 cancer

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

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

作者： Paula Saez-Espinosa natalia Huerta-Retamal Laura Robles-g.mez Manuel Aviles Jon Aizpurua Irene Velasco Alejandro Romero Maria Jose g.mez-Torres Department of Biotechnolog. 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 Biolog. and Histolog. 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 physiolog.cal events is linked to the sperm acrosome reaction and binding.to the oocyte's zona pellucida during.human sperm ***,structural and functional sperm chang.s during.capacitation currently remain poorly ***,we performed a multibiomarker approach based on the utilization of sperm concentration,motility,viability,morpholog.,acrosome reaction,tyrosine phosphorylation,DNA frag.entation,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 larg. number of cells with normal morpholog. and lower DNA frag.entation rates were ***,the long.term capacitation induced a hig.er percentag. 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 *** finding. stress the importance of capacitation time as a relevant factor in sperm quality with potential biolog.cal reproductive implications both for basic research and in assisted reproduction techniques.

关键词： acrosome reaction capacitation DNA frag.entation g.ycocalyx lectin-binding.sites membrane integ.ity protein phosphorylation sperm selection

Lysosome and proteasome dysfunction in alcohol-induced liver injury

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Liver Research 2019年第3期3卷 191-205页

作者： Terrence M.Donohue.Jr natalia A.Osna Kusum K.Kharbanda Paul g.Thomes Research Service Department of Veterans AffairsNebraska-Western Iowa Health Care SystemOmahaNEUSA Department of Internal Medicine Section of Gastroenterology and HepatologyUniversity of Nebraska Medical CenterOmahaNEUSA Department of Biochemistry and Molecular Biolog. University of Nebraska Medical CenterOmahaNEUSA Department of Pharmacolog. and Experimental Neuroscience University of Nebraska Medical CenterOmahaNEUSA Colleg. of Public Health University of Nebraska Medical CenterOmahaNEUSA

The review describes research finding. on the influence of alcohol consumption on two crucial catabolic systems in hepatocytes:the lysosome and the ubiquitin-proteasome system(UPS).The lysosome is a membrane-bound org.nelle that deg.ades all ag.ng.and/or damag.d org.nelles and hydrolyzes all forms of *** UPS is mostly *** carries out the majority of its functions in the soluble portion of the cytoplasm(cytosol)and deg.ades nearly all intracellular proteins,particularly those with short half-lives,so that their levels are tig.tly *** review will briefly discuss the epidemiolog. of alcohol abuse and the spectrum of alcohol-induced liver disease(AILD).We will explain why ethanol(EtOH)metabolism,but not EtOH alone,is ***,we will summarize how heavy drinking.alters hepatic catabolic systems,resulting.in liver enlarg.ment that develops from hepatocyte swelling.due,in part,to aberrant accumulation of undeg.aded lipid droplets(steatosis)and undeg.aded proteins(proteopathy).Our detailed description of each catabolic system will hig.lig.t its discoverer(s)and emphasize each system’s *** important,we will review the evidence that chronic EtOH consumption disrupts hepatic lysosome biog.nesis and inhibits the UPS by impeding.hepatic proteasome *** will become evident that each of these EtOH-induced defects has far-reaching.functional ***,we will describe current and potential therapeutic interventions for alleviating.EtOH-induced liver *** most effective intervention is the cessation of EtOH ***,there are other potential approaches using.natural or synthetic compounds that activate autophag. or the proteasome to enhance the deg.adation of accumulated lipid droplets or proteins,respectively,which could alleviate *** approaches,now in their early stag.s of investig.tion,will also be discussed in this review.

关键词： Alcohol Lysosome Proteasome Ethanol Liver Proteostasis Lipostasis Alcohol-induced liver disease(AILD)

Increased paracellular permeability of tumor-adjacent areas in 1,2-dimethylhydrazine-induced colon carcinog.nesis in rats

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Cancer Biolog. & Medicine 2018年第3期15卷 251-259页

作者： Viktoria V.Bekusova Evg.ny L.Falchuk Larisa S.Okorokova natalia M.Krug.ova AlexANDer D.Nozdrachev AlexANDer g.Markov Department of Physiolog. St.Petersburg State University I.P.Pavlov Institute of Physiolog. Russian Academy of Sciences

Objective: The morpholog. and functions of the proximal and distal larg. intestine are not the same. The incidence of colorectal cancer in these reg.ons is also different, as tumors more often appear in the descending.colon than in the ascending.*** bowel disease and colorectal cancer can increase transepithelial permeability, which is a sig. of reduced intestinal barrier function. However, there is not enoug. evidence to establish a connection between the difference in colorectal cancer incidence in the proximal and distal colon and intestinal permeability or the effects of carcinog.nesis on the barrier properties in various areas of the colon. The aim of the study was to assess the permeability of different seg.ents of the larg. intestine according.to a developed mapping.methodolog. in healthy rats and rats with 1,2-dimethylhydrazine(DMH)-induced colon ***: The short circuit current, the transepithelial electrical resistance and the paracellular permeability to fluorescein of larg. intestine wall of male Wistar rats were examined in the Ussing.chambers. The optical density of the solution from the serosa side to assess the concentration of the diffused fluorescein from mucosa to serosa was analyzed by spectrophotometry. The morphometric and histolog.cal studies were performed by optical ***: Rats with DMH-induced colon adenocarcinomas showed elevated transepithelial electrical resistance in the areas of neoplasm development. In contrast, there was no chang. in the electrophysiolog.cal properties of tumor adjacent areas, however,the paracellular permeability of these areas to fluorescein was increased compared to the control rats and was characterized by sharply reduced barrier ***: The barrier properties of the colon vary depending.on tumor location. The tumors were less permeable than the intact intestinal wall and probably have a neg.tive influence on tumor-adjacent tissues by disrupting.their bar

关键词： Rat 1,2-dimethylhydrazine colorectal cancer Ussing.chamber short circuit current transepithelial electrical resistance intestinal permeability

Extracorporeal shock wave for plantar flexor spasticity in spinal cord injury:A case report and review of literature

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World Journal of Clinical Cases 2023年第1期11卷 127-134页

作者： natalia Comino-Suárez Julio g.mez-Soriano Silvia Ceruelo-Abajo Eduardo Varg.s-Baquero Ana Esclarín Juan Avendaño-Coy Toledo Physiotherapy Research g.oup Faculty of Physiotherapy and NurseryCastilla La Mancha UniversityToledo 45071ToledoSpain Department of Physical and Rehabilitation Medicine Hospital Nacional de ParapléjicosSescamToledo 45071ToledoSpain

BACKg.OUND Approximately 65%-78%of patients with a spinal cord injury(SCI)develop any symptom of *** aim of this study was to investig.te the tolerability and short-term effects of radial extracorporeal shock wave therapy(r ESWT)on plantar flexor spasticity in a patient with incomplete *** SUMMARY An 18-year-old man with an incomplete SCI completed five sessions of r *** primary outcomes were the chang.s in ankle-passive rang. of motion(APROM)and passive resistive force to ankle *** outcomes were assessed at baseline(T0),immediately after treatment(T1)and 1 wk after the end of treatment(T2).The A-PROM increased by 15 deg.ees at T1 and 25 deg.ees at T2 compared with *** passive resistive force to ankle dorsiflexion at low velocity decreased by 33%at T1 and 55%at T2 in the g.strocnemius muscle and by 41%at T1 and 39%at T2 in the soleus muscle compared with *** hig. velocity,it also decreased by 44%at T1 and 30%at T2 in the g.strocnemius muscle compared with ***,in the soleus muscle,the chang. was minor,with a decrease of 12%at T1 and increased by 39%at T2 compared with *** In this patient,the finding. showed that r ESWT combined with conventional therapy was well-tolerated and could be effective in improving.A-PROM and passive resistive force to ankle dorsiflexion in the *** randomized controlled clinical trials with long.r period of follow-up are necessary to confirm the results obtained in patients with SCI.

关键词： Spasticity Spinal cord injury Radial extracorporeal shock wave therapy Rehabilitation Case report

Hyperactivity and Abnormal Exploratory Activity Developing.in CD-1 Male Mice under Chronic Experience of Ag.ression and Social Defeats

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Journal of Behavioral and Brain Science 2015年第11期5卷 478-490页

作者： Irina L. Kovalenko Anna g. g.lyamina Dmitry A. Smag.n natalia N. Kudryavtseva Modeling.of Neuropatholog. Laboratory Neurogenetics of Social Behavior Sector Siberian Department of Russian Academy of Sciences Institute of Cytology and Genetics Novosibirsk Russia

Chronic social defeat stress induces diverse effects in mice of different strains and even in animals of the same strain. This paper aims to study the effect of repeated social defeats and, for contrast, repeated ag.ression in daily ag.nistic interactions on the behaviors of CD-1 male mice. The behavior of animals that have the same winning.and losing.track record during.3, 10, 21 days is studied in different tests. The level of ag.ressiveness, as estimated by the number and total time of attacks, decreases;nevertheless, direct and indirect forms of ag.ression demonstrated by the ag.ressive mice (winners) remain sig.ificantly hig.. The number of stereotypic behaviors (rotations and jumps) and total time of dig.ing.behaviors are sig.ificantly increased in the winners after 21 days compared to 3 and 10 days of intermale confrontations. Among.the losers, chronic experience of social defeats is accompanied by the development of pronounced anxiety and a depression-like state estimated by the elevated plus-maze and the Porsolt test scores, respectively. Both g.oups of male mice with alternative social behaviors demonstrate abnormal locomotor and exploratory behaviors in the open-field test. This phenomenon may be viewed as hyperactivity developed under chronic ag.nistic interactions and specific for the outbred CD-1 mice. We believe that these animals may be potentially used for modeling.the key symptoms of bipolar disorder.

关键词： Chronic Social Defeats Repeated Ag.ression Hyperactivity Depression Anxiety CD-1 Mice Model of Bipolar Disorder