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npj Computational Materials 2023年第1期9卷 1469-1481页

作者： Kate l.M.Elder joel Berry Aurélien Perron Brandon Bocklund Jibril Shittu Connor J.Rietema Hunter B.Henderson Scott K.McCall Joseph T.McKeown Materials Science Division Lawrence Livermore National LaboratoryLivermoreCA 94550USA.✉

Here the discovery of refractory multi-principal element alloys(MPEAs)with high-temperature strength and stability is pursued within a constrained and application-relevant design space.A comprehensive approach is developed and applied to explore all 165 ternary systems in the Al-Ce-Fe-Hf-Mo-Nb-Ta-Ti-V-W-Zr family.A subset of ternary systems that contain large areas in composition–temperature space with high strength and robust BCC phase stability is *** sets of high-performing alloys are identified,each set optimized for one combination of phase constraint,optimization target,and temperature *** mechanical tests support the viability of the *** work highlights the importance of considering phase stability,exploring non-equiatomic regions of composition space,and applying application-relevant *** I and II provide three down-selection techniques for identifying high-performing BCC refractory MPEAs,design guidelines,and many candidates predicted to have BCC phase stability and strengths 2–3 times higher than any reported to date.

关键词： alloys element ternary

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Attenuation of gastric mucosal inflammation induced by aspirin through activation of A_(2A) adenosine receptor in rats

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World Journal of Gastroenterology 2006年第4期12卷 568-573页

作者： MasaruOdashima MichiroOtaka MarioJin KogaKomatsu IsaoWada YouheiHorikawa TamotsuMatsuhashi NatsumiHatakeyama JinkoOyake ReinaOhba SumioWatanabe joel linden Department of Gastroenterology Akita University School of MedicineAkitaJapan Cardiovascular Research Center University of VirginiaCharlottesvilleVAUnited States

AIM： To determine whether a specific adenosine A2A receptor agonist （ATl-146e） can ameliorate aspirin-induced gastric mucosal lesions in rats, and reduce neutrophil accumulation and production of pro-inflammatory cytokines. METHODS： Gastric lesions were produced by oral gavage of aspirin （200 mg/kg） and HCI （0.15 mol/l, 8.0 ml/kg）. 4-{3-[6-Amino-9-（5-ethylcarbamoyl-3,4- dihydroxy-tetrahydro-furan-2-yl）-9H-purin-2-yl]-prop-2- ynyl}-cyclohexanecarboxylic acid methyl ester （ATl-146e, 2.5-5μg/kg, IP） was injected 30 min before the administration of aspirin. Tissue myeloperoxidase （MPO） concentration in gastric mucosa was measured as an index of neutrophil infiltration. Gastric mucosal concentrations of tumor necrosis factor-α （TNF-α） and interleukin-1β （Il-1β） were determined by ElISA. Also, we examined the effect of ATl-146e on tissue prostaglandin E2 （PGE2） production and gastric secretion. RESUlTS： Intragastric administration of aspirin induced multiple hemorrhagic erosions in rat gastric mucosa. The total length of gastric erosions （ulcer index） in control rats was 29.8±7.75 mm and was reduced to 3.8±1.42 mm alter pretreatment with 5.0 g/kg ATl-146e （P〈 0.01）. The gastric contents of MPO and pro-inflammatory cytokines were all increased after the administration of aspirin and reduced to nearly normal levels by ATl-146e. Gastric mucosal PGE2 concentration was not affected by intraperitoneal injection of ATl-146e. CONClUSION： The specific adenosine A2A receptor agonist, ATl-146e, has potent anti-ulcer effects presumably mediated by its anti-inflammatory properties.

关键词： Aspirin Pro-inflammatory cytokine Adenosine A2A receptor ATl-146e Gastric injury

Shade shelters increase survival and photosynthetic performance of oak transplants at abandoned fields in semi-arid climates

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Journal of Forestry Research 2013年第1期24卷 23-28页

作者： Claudia González-Salvatierra Ernesto Iván Badano joel Flores Juan Pablo Rodas División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaA.C.Camino a la Presa San José 2055C.P. 78216San Luis PotosíS.L.P.México.

Forest restorations conducted in semiarid, seasonally dry climates must deal with the intense drought stress that affects tree seedlings during the dry season. Although this water deficit is the most commonly invoked source of mortality for seedlings, several other environmental factors may also preclude survival of transplants. For instance, it has been widely reported that excessive light reduces the efficiency of the photosynthetic apparatus, hence decreasing plant survival, but most seedling transplants in deforested areas are conducted under these light conditions. This study is focused in determining whether excessive light affects the photosynthetic performance and survival of Quercus coccolobifolia, a Mexican oak species, when their seedlings are transplanted in semiarid deforested areas. Further, this study tests the possibility of using artificial shade shelters to improve the ecophysiological performance and survival of seedlings. Oak seedlings were transplanted under full sunlight conditions and beneath artificial shade shelters of two different colors： white and black. To reduce water stress, and hence isolate the effects of light treatments, a drip irrigation system was implemented at each experimental plot. Seedling survival was monitored weekly for 128 days and photosynthetic performance was assessed by measuring chlorophyll fluorescence at three opportunities during the experiment. Sun-exposed seedlings showed lower photosynthetic performance and survival rates than those beneath shelters of both colors. These results suggest that sunlight damage can reduce seedling survival when they are transplanted in exposed sites, and that shade shelters can improve the success of forest restoration programs in semiarid climates.

关键词： chlorophyll fluorescence light stress photoinhibition reforestation forest restoration

Tree diversity and nectar composition affect arthropod visitors on extrafloral nectaries in a diversity experiment

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Journal of Plant Ecology 2017年第1期10卷 201-212页

作者： Michael Staab joel Methorst Jan Peters Nico Blüthgen Alexandra-Maria Klein Faculty of Environment and Natural Resources Chair of Nature Conservation and Landscape EcologyUniversity of FreiburgTennenbacher Straße 479106 FreiburgGermany Institute of Ecology Leuphana University of LüneburgScharnhorststraße 121335 LüneburgGermany Ecological Network Group Department of BiologyTechnical University DarmstadtSchnittspahnstraße 1064287 DarmstadtGermany

Aims Plants with extrafloral nectaries(EFNs)are common in tropical and subtropical habitats and,despite many other arthropods also forage for EFN,most studies solely focused on the defense mutualisms between EFN plants and *** study aims at a quantitative assessment of the entire arthropod community that visits EFN trees to compare visitor communities between different tree species to disentangle the mechanisms that may drive EFN visitor community *** also test for tree diversity effects on EFN visitors,as it is unknown if local tree species richness relates to the abundance and species richness of arthropods foraging for *** We sampled EFN-visiting arthropods in the experimental tree species richness gradient of the BEF-China Experiment,the currently largest forest diversity experiment in the world,and tested if tree species richness affects EFN visitors and if visitor community composition differs between EFN tree *** a second step,we analyzed the EFN of Ailanthus altissima and Triadica cochinchinensis,the two EFN tree species with highest visitor abundance,for sugars and amino acids(AA)to test if tree species-specific differences in nectar chemistry translate to differing visitor ***,we conducted a choice experiment using different artificial nectar solutions to test if nectar quality affects foraging decisions of ants,the most frequent EFN visitors in our study *** Findings EFN trees in young successional forests in subtropical South-East China are visited by a diverse assemblage of arthropods including ants,beetles,flies,and *** ants accounted for about 75%of all individuals,non-ant visitors were by far more species *** abundance and species richness declined with increasing tree species richness,suggesting a resource dilution effect,because plots with more tree species had proportionally less EFN tree individuals and thus lower nectar *** altissima and ***

关键词： amino acids BEF-China choice experiment formicidae HPlC chemical analysis

Bacterial microcosms obey Taylor’s law:effects of abiotic and biotic stress and genetics on mean and variance of population density

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Ecological Processes 2012年第1期1卷 77-82页

作者： Oliver Kaltz Patricia Escobar-Páramo Michael E Hochberg joel E Cohen Institut des Sciences de l’Evolution UMR CNRS-UM2-IRD5554CC 065UniversitéMontpellier 2Place Eugène BataillonMontpellier Cedex 0534095France Centro Internacional de Física(CIF) Biotechnology GroupUniversidad Nacional de ColombiaCra 30 N°45-03BogotáDCColombia laboratory of Populations Rockefeller and Columbia Universities1230 York AvenueBox 20New YorkNY10065-6399USA

Introduction:According to the empirical regularity called Taylor’s law,the variance of population density in samples of populations is a power of the mean population *** exponent is often between 1 and *** experiments investigated how genetics,evolution,and environment shape Taylor’s ***:Genetically different strains(wild type and hypermutator)of the bacterium Pseudomonas fluorescens evolved and were assayed under different environmental conditions(with and without antibiotic rifampicin and bacteriophage SBW252,separately and in combination).Results:Experimental treatments altered the exponent b,but not the power law form,of the relation between variance and mean population *** populations treated only with rifampicin had a narrow range of mean population densities and exponent b=*** exposed to rifampicin plus phage had b=*** ancestral,control,and phage-exposed populations,mean abundance varied widely and b was not significantly different from *** factors(mutation rate,selection)and ecological factors(abiotic,biotic)jointly influenced ***:Taylor’s power law relationship accurately and robustly described variance as a function of mean population density,with overall exponent b=*** and other experiments with different factors acting on bacterial population size support the relevance of models that predict‘universal’patterns of fluctuation scaling.

关键词： Taylor’s law Pseudomonas fluorescens rifampicin bacteriophage genetics

Facilitation by nurse plants contributes to vegetation recovery in human-disturbed desert ecosystems

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Journal of Plant Ecology 2016年第5期9卷 485-497页

作者： Ernesto I.Badano Omar R.Samour-Nieva joel Flores Josél.Flores-Flores Jorge A.Flores-Cano Juan P.Rodas-Ortíz División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaA.C.Camino a la Presa San José2055Colonia Lomas 4ta SecciónC.P.78216San Luis PotosíMéxico Instituto de Investigación de Zonas Desérticas Universidad Autónoma de San Luis PotosíAltair 200Fraccionamiento del LlanoC.P.78377San Luis PotosíMéxico Facultad de Agronomía Universidad Autónoma de San Luis PotosíKm.14.5 Carretera San Luis-MatehualaApdo.Postal 32Soledad de Graciano SánchezC.P.78321San Luis PotosíMéxico

Aims Facilitation by nurse plants is a common interaction in harsh environments and this positive plant-plant interaction may promote vegetation recovery in ecosystems affected by human *** the relevance of this process,however,requires assessing how nurse plants influence the establishment of other species,as well as the proportion of species in the regional species pool that would benefit from the presence of nurse plants in human-disturbed ***,since vegetation recovery is a time-dependent process,the community-level consequences of facilitation are likely to vary among landscapes with different disturbance ***,an integrative perspective of the relevance of nurse plants for vegetation recovery could be obtained by measuring their effects across different human-disturbed landscapes of the target *** study focuses on these issues and uses a regional-scale approach to assess the community-level effects of a widespread nurse plant of American deserts,the creosotebush(larrea tridentata).Methods This study was conducted in the southernmost portion of Chihuahuan Desert because most floodplain valleys of this region have been affected by human activities during the past *** this study,we selected 10 floodplain valleys differing in their age(*** time elapsed after human activities were ceased).At each landscape,we measured the cover of creosotebushes and the proportion of plant species positively associated with them,as well as the density of seeds in the soil beneath creosotebush *** these data were regressed against the age of the ***,to assess whether positive association patterns were due to facilitation or other processes,we conducted field experiments and measured the ecophysiological performance of plant species established beneath and outside creosotebush *** Findings Most plant species from the target region were positively associated to creosotebushes,and our field

关键词： Chihuahuan desert community-level effects community succession positive interactions Mexico

A tabletop X-ray tomography instrument for nanometer-scale imaging: reconstructions

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Microsystems & Nanoengineering 2023年第2期9卷 249-259页

作者： Zachary H.levine Bradley K.Alpert Amber l Dagel Joseph W.Fowler Edward S.Jimenez Nathan Nakamura Daniel S.Swetz Paul Szypyt Kyle R.Thompson joel N.Ulom National Institute of Standards and Technology GaithersburgMD 20899USA National Institute of Standards and Technology BoulderCO 80305USA Sandia National laboratories AlbuquerqueNM 87123USA Department of Physics University of ColoradoBoulderCO 80309USA

We show three-dimensional reconstructions of a region of an integrated circuit from a 130 nm copper *** reconstructions employ x-ray computed tomography,measured with a new and innovative high-magnification x-ray *** instrument uses a focused electron beam to generate x-rays in a 100 nm spot and energy-resolving x-ray detectors that minimize backgrounds and hold promise for the identification of materials within the *** x-ray generation target,a layer of platinum,is fabricated on the circuit wafer itself.A region of interest is imaged from a limited range of angles and without physically removing the region from the larger *** reconstruction is consistent with the circuit's design file.

关键词： process removing platinum

Electrospun polyvinyl alcohol fibres incorporating an antimicrobial gel for enzymatically controlled reactive oxygen species release

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Bio-Design and Manufacturing 2024年第6期7卷 899-925页

作者： joel Yupanqui Mieles Cian Vyas Evangelos Daskalakis Mohamed Hassan James Birkett Abdalla M.Omar Gavin Humphreys Carl Diver Paulo Bartolo Department of Mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchester M139PLUK Singapore Centre for 3D Printing School of Mechanical and Aerospace EngineeringNanyang Technological UniversitySingapore 639798Singapore Department of Chemistry University of ManchesterManchester M139PLUK Division of Pharmacy and Optometry University of ManchesterManchester M139PLUK Department of Engineering Manchester Metropolitan UniversityManchester M139PLUK

Wounds pose a risk to the skin,our body's primary defence against *** rise of antibiotic resistance has prompted the development of novel ***-101^(■)is an antimicrobial gel that delivers therapeutic levels of hydrogen peroxide(H_(2)O_(2)),a reactive oxygen species,directly to the wound *** this study,electrospinning was used to incorporate RO-101^(■)into a polyvinyl alcohol(PVA)sub-micron fibrous mesh that can act as a delivery agent,achieve a sustained release profile,and provide a barrier against *** incorporation of this gel into sub-micron fibres was confirmed via nuclear magnetic resonance ***,scanning electron microscopy exhibited smooth and uniform meshes with diameters in the 200-500 nm ***/RO-101 electrospun meshes generated H_(2)O_(2) in concentrations exceeding 1 m M/(g·m l)(1 m M=1 mmol/l)after 24 h,and the role of sterilisation on H_(2)O_(2) release was ***/RO-101meshes exhibited antimicrobial activity against both Gram-positive Staphylococcus aureus(***)and Gram-negative Pseudomonas aeruginosa(***)bacteria,achieving viable count reductions of up to 1 log unit CFU/mm^(2)(CFU:colony-forming units).Moreover,these meshes were capable of disrupting biofilm formation,even against multidrug-resistant organisms such as methicillin-resistant ***(MRSA).Furthermore,increasing the RO-101^(■)concentration resulted in higher H_(2)O_(2) production and an enhanced antimicrobial effect,while fibroblast cell viability and proliferation tests showed a concentration-dependent response with high cytocompatibility at low RO-101^(■)*** study therefore demonstrates the potential of highly absorbent PVA/RO-101 meshes as potential antimicrobial wound dressings.

关键词： Antimicrobial Electrospinning Hydrogen peroxide Polyvinyl alcohol Reactive oxygen species Tissue engineering Wound dressing

子痫前期及大脑二者关系可能与后期痴呆相关,需要深入研究

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英国医学杂志中文版 2019年第5期22卷 249-250页

作者： joel G Ray Alison l Park 李洁(译) 毛晨晖(校) Departments of Medicine Health Policy Management and Evaluationand Obstetrics and GynecologySt Michael' s HospitalTorontoONCanada Institute for Clinical Evaluative Sciences University of TorontoTorontoONCanada 北京协和医院神经科

在一篇相关的文章里(doi:10.1136/bmj.k4109,摘要见本期第251页),Basil及他的同事研究伴或不伴子痫前期病史的女性患痴呆的风险在中位数为21.1年的随访过后,他们报道至少一次妊娠中患有子痫前期的女性相较于没有此病史的女性患有血管性... 详细信息

在一篇相关的文章里(doi:10.1136/bmj.k4109,摘要见本期第251页),Basil及他的同事研究伴或不伴子痫前期病史的女性患痴呆的风险在中位数为21.1年的随访过后,他们报道至少一次妊娠中患有子痫前期的女性相较于没有此病史的女性患有血管性痴呆的风险高岀3.5倍(共105例),患有阿尔茨海默病的风险高1.5倍(676例),患有其他或非特异性痴呆的风险高1.4倍(947例)。

关键词：血管性痴呆子痫前期大脑阿尔茨海默病非特异性风险中位数女性

Genome-Wide SNPs Identification and Determination of Proteins Associated with Stress Response in Sorghum (<i>Sorghum bicolor</i>l. Monech) Accessions

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American Journal of Plant Sciences 2017年第7期8卷 1624-1631页

作者： Hind Emad Fadoul marmar A. El Siddig Abdel Wahab H. Abdalla Adil A. El Hussein Department of Botany Faculty of Science University of Khartoum Sudan Department of Agronomy Faculty of Agriculture University of Khartoum Sudan

Current efforts in sorghum breeding programs are exploiting genotyping-by-sequencing (GBS) data to provide full-genome scans for desired traits. The aim of this study was to utilize GBS approach for the identification of genomic regions associated with stress response in sorghum (Sorghum bicolor l. Monech) accessions. DNA samples of twenty sorghum accessions, having different response to drought, were used to prepare GBS libraries for sequencing. SNPs were called using the TASSElGBS pipeline and the tags that present at least 10 times in the dataset were considered and aligned to the reference genome of Sorghum bicolor. The identified SNPs were all compared with the published sorghum transcript related to stress response gene activity. Overall;94.40% tags were aligned and 69,736 putative SNPs positions were identified. Blast search revealed homology to annotated heat and drought–tolerance associated genes which code for ATPases, Peroxidase, Hydrophobic protein lTI6A, Aquaporin SIP2-1, Aconitate hydratase and phosphatidylinositol-4-phosphate-5-kinase. The phylogeny of the 20 accessions was constructed using the generated SNPs data. Phylogenetic analysis data showed that the phenotypically tolerant line (El9)?makes a separate cluster and the same for the accessions HSD8653 and HSD5612 near to the cluster that includes most accessions with known post-flowering drought tolerance (HSD7410, HDS10033, HSD8552, GESHEISH and HSD8849). Post-flowering drought sensitive accessions (Tabat, Wadahmed, HSD6468 and HSD6478) formed a separate cluster while the sensitive accession HSD9959 and the tolerant accessions HSD8511 and HSD9566 were distributed between the two clusters. Thus, cluster analysis confirmed the variation among accessions in post-flowering drought tolerance. With further validation, these markers may be used for marker assisted selection for breeding new sorghum genotypes with stress adaptation.

关键词： SNPs Sorghum Stress Response GBS