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The transport of chemical components in homogeneous snowpacks on Urumqi Glacier No.1, eastern Tianshan Mountains, Central Asia

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Journal of Arid Land 2015年第5期7卷 612-622页

作者： YOU Xiaoni LI Zhongqin ross EDWARDS WANG Lixia Key Laboratory of Cryosphere and Environment/Tianshan Glaciological Station/Laboratory of Ice Core and Cold Regions Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Tianshui Normal University Imaging and Applied Physics Curtin University of Technology

Chemical records from alpine ice cores provide an invaluable source of paleoclimatic and environ- mental information. Not only the atmospheric chemical composition but also depositional and post-depositional processes are recorded within snow/tim strata. To interpret the environmental and climatic significance of ice core records, we studied the variability of glacier snowpack chemistry by investigating homogeneous snowpacks from October 2003 to September 2006 on Urumqi Glacier No. 1 in eastern Tianshan Mountains, Central Asia. Principle Component Analysis of ionic species in dry and wet seasons revealed the impact of meltwater in redistributing ions in the snowpacks. The 1st, 2nd and 3rd principle components for dry seasons differ significantly, reflecting complex associations between depositional or/and post-depositional processes. The variability trend of ionic concentrations during the wet seasons was found to fit a Gauss Function with significant parameters. The elution factor revealed that more than half of ions are leached out during the wet seasons. Differences with respect to ion snowpack mo- bility were found. Of the ions studied SO42- was the most mobile and Mg2＋ the least mobile. A threshold relationship between air temperatures and the elution process was investigated over the study period. The results indicate that the strong melt/ablation processes and iconic redistribution occur at a threshold air temperature of 0℃. The study found that surface melt on the snowpacks is the main factor causing the alteration of the snowpack chemistry. Rainfall also has an impact on the chemistry but plays a less significant role than the surface melt.

关键词： Urumqi Glacier No. 1 snowpack meltwater air temperature precipitation

Differential modulation of bradykinin-induced relaxation of endothelin-1 and phenylephrine contractions of rat aorta by antioxidants

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Acta Pharmacologica Sinica 2007年第10期28卷 1566-1572页

作者： Ogechukwu ANOZIE Richonda ross Adebayo O OYEKAN Momoh A YAKUBU Vascular Biology UnitCenter for Cardiovascular Diseases College of Pharmacy and Health Sciences Texas Southern University Houston Texas 77004 USA

Aim:We tested the hypothesis that bradykinin （BK）-induced relaxation of phe-nylephrine （PE） and endothelin-1 （ET-1） contractions can be differentially modu-lated by reactive oxygen species （ROS）.Methods:Aortic rings isolated fromSprague-Dawley rats were used for the *** contribution of ROS to PE(1×10-9-1×10-5mol/L)-and ET-1 (1×10-10-1×10-8mol/L)-induced contractions andthe influence of ROS in BK (1×10-9-1×10-5mol/L) relaxation of PE (1×10-7mol/L) orET-1 (1×10-9mol/L)-induced tension was evaluated in the aorta in the presence orabsence of the following antioxidants:catalase （CAT,300 U/mL）,superoxidedismutase （SOD,300 U/mL）,and vitamin C (1×10-4mol/L).Results:Tension gen-erated by ET-1 (1×10-9mol/L) or PE (1×10-7mol/L) was differentially relaxed by BK(1×10-5mol/L),producing a maximal relaxation of 75%±5% and 35±4%,*** BK (1×10-5mol/L)-induced relaxation of PE (1×10-7mol/L) tension was signifi-cantly enhanced from 35%±4% （control） to 56%±9%,60%±5%,and 49%±6% bySOD,CAT,and vitamin C,respectively （P<0.05,n=8）.However,the relaxation ofET-1 (1×10-9mol/L) tension was significantly attenuated from 75%±5% （control）to 37%±9%,63%±4%,and 39%±7% by SOD,CAT,and vitamin C,respectively（P<0.05,n=8）.On the other hand,CAT had no effect on PE-induced tension,whileSOD enhanced PE-induced tension （36%,P<0.05,n=10） and vitamin C attenuated（66%,P<0.05,n=8） the tension induced by *** contrast,SOD or vitamin C hadno effect,but CAT attenuated （44%,P<0.05,n=9） the tension induced by ***:We have demonstrated that O2-and H2O2differentially modulate BKrelaxation in an agonist-specific manner.O2-attenuates BK-induced relaxation ofPE contraction,but contributes to the relaxation of ET-1 contraction.O2-seems toinhibit PE contraction,while H2O2contributes to ET-1-induced ***,ROS differentially modulate vascular tone depending on the vasoactive agentthat is used to generate the tone.

关键词： bradykinin endothelin-1 phenylephrine reactive oxygen species superoxide hydrogen peroxide relaxation contraction antioxidants

Heat tolerance may determine activity time in coprophagic beetle species (Coleoptera:Scarabaeidae)

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Insect Science 2021年第4期28卷 1076-1086页

作者： Nonofo Gotcha Honest Machekano ross N.Cuthbert Casper Nyamukondiwa Department of Biological Sciences and Biotechnology Botswana International University of Science and TechnologyPalapyeBotswana GEOMAR Helmholtz-Zentrum fur Ozeanforschung KielKielGermany

Although reports have documented loss of species diversity and ecological services caused by stressful temperature changes that result from climate change,some species cope through behavioral *** temperatures and magnitudes of temperature extremes increase,animals should compensate to maintain fitness(such as through temporary behavioral shifts in activity times).Appropriate timing of activity helps avoid competition across *** coprophagic dung beetles exhibit species-specific temporal activity times,it is unknown whether temperature drives evolution of these species-specific temporal activity *** nine dung beetle species(three each of diurnal,crepuscular,and nocturnal species),we explored differences in heat stress tolerance measured as critical thermal maxima(CTmax;the highest temperature allowing activity)and heat knockdown time(HKDT;survival time under acute heat stress)across these species,and examined the results using a phylogenetically informed *** results showed that day-active species had significantly higher CTmax(diurnal>crepuscular=nocturnal species),whereas crepuscular species had higher HKDT(crepuscular>nocturnal>diurnal species).There was no correlation between heat tolerance and body size across species with distinct temporal activity,and no significant phylogenetic constraint for *** with higher CTmax did not necessarily have higher HKDT,which indicates that species may respond differently to diverse heat tolerance *** heat tolerance for diurnal beetles indicates that this trait may constrain activity time and,under high acute temperatures with climate change,species may shift activity times in more benign *** results contribute to elucidate the evolution of foraging behavior and management of coprophagic beetle ecosystem services under changing environments.

关键词： biodiversity climate change dung beetle ecosystem services thermal tolerance

Sex differences in cognition and their relationship to male mate choice

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Current Zoology 2019年第3期65卷 285-293页

作者： Jason KEAGY ross MINTER Robin M.TINGHITEELLA Department of Animal Biology School of Integrative Biology University of Illinois at Urbana-Champaign Urbana IL USA Linda Crnic Institute for Down Syndrome University of Colorado School of Medicine Aurora CO USA Department of Biological Sciences University of DenverDenverCOUSA

Male cognition has gained recognition as an important potential player in sexual selection. A number of studies have found positive correlations between male sexual signals and cognitive performance an d/or female pref ere nces for males with better cog nitive performance, although other studies have not fou nd these relati on ships. Sex roles can differ dramatically, and sex differen ces in selection on cog nition likely follow from the different tasks associated with these sex roles. Here, using threespine stickleback Gasterosteus aculeatus, a species with clearly diverge nt sex roles and mutual mate choice, we focus on the cognitive trait inhibitory control because males must differentially respond to reproductive females versus other sticklebacks while defending territories and refrain from eating eggs and fry while performing paternal care. We presented fish with a detour task four times over a period of 7 days, allowing us to assess initial inhibitory control and improvement over time. We ask 1) whether there are sex differences in inhibitory control and 2) whether male mate choice is associated with female inhibitory control. Although males outperformed females on three different measures of detour task performance across four trials, these differences were largely explained by males being less neophobic than females. Females took more trials to successfully solve the detour task, even after accounting for sex differences in neophobia. Female cognitive abilities, however, were unrelated to the vigor with which males courted them. The equivocal results regarding sex differences in cognitive ability suggest further study given the very different selection pressures each sex experiences.

关键词： cognition detour task mutual mate choice sexual selection threespine stickleback

Geographic variability of Twitter usage characteristics during disaster events

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Geo-Spatial Information Science 2017年第3期20卷 231-240页

作者： Kiran Zahra Frank O.Ostermann ross S.Purves Department of Geography University of ZurichZurichSwitzerland Faculty of Geo-Information Science and Earth Observation(ITC) University of TwenteEnschedeThe Netherlands

Twitter is a well-known microblogging platform for rapid diffusion of views,ideas,and *** disasters,it has widely been used to communicate evacuation plans,distribute calls for help,and assist in damage *** reliability of such information is very important for decision-making in a crisis situation,but also difficult to *** is little research so far on the transferability of quality assessment methods from one geographic region to *** main contribution of this research is to study Twitter usage characteristics of users based in different geographic locations during *** examine tweeting activity during two earthquakes in Italy and *** compare the granularity of geographic references used,user profile characteristics that are related to credibility,and the performance of Naive Bayes models for classifying Tweets when used on data from a different region than the one used to train the *** results show similar geographic granularity for Myanmar and Italy earthquake events,but the Myanmar earthquake event has less information from locations nearby when compared to ***,there are significant and complex differences in user and usage characteristics,but a high performance for the Naive Bayes classifier even when applied to data from a different geographic *** research provides a basis for further research in credibility assessment of users reporting about disasters.

关键词： Geographic feature granularity Volunteered Geographic Information(VGI) Naive Bayes Twitter credibility Geonames

Numerical Modeling of Shallow Water Table Behavior with Lisse Effect

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Chinese Geographical Science 2011年第2期21卷 249-256页

作者： ZHANG Jinga GONG Huili Mark A ross LI Xiaojuan ZHOU Demin Key Laboratory of Resource Environment and GIS of Beijing Capital Normal University Beijing 100048 China Department of Civil and Environmental Engineering University of South Florida 4202 E. FowlerAve ENB 118 Tampa FL 33620 USA

Air entrapment is an important consideration in environments with shallow water tables and sandy soil, like the condition of highly conductive sandy soils and flat topography in Florida, USA. It causes water table rises in soils, which are significantly faster and higher than those in soils without air entrapment. Two numerical models, Integrated Hydrologic Model (IHM) and HYDRUS-1D (a single-phase, one-dimensional Richards′ equation model) were tested at an area of west central Florida to help further understanding the shallow water table behavior during a long term air entrapment. This investigation employed field data with two modeling approaches to quantify the variation of air pressurization values. It was found that the air pressurization effect was responsible at time up to 40 cm of water table rise being recorded by the observation well for these two models. The values of air pressurization calculated from IHM and HYDRUS-1D match the previously published values. Results also indicated that the two numerical models did not consider air entrapment effect (as the predictive parameters remain uncertain) and thus results of depth to water table from these models did not compare to the observations for these selected periods. Incorporating air entrapment in prediction models is critical to reproduce shallow water table observations.

关键词： shallow water table Lisse effect air entrapment Integrated Hydrologic Model (IHM) HYDRUS-1D Florida

Effects of native and invasive Prosopis species on topsoil physiochemical properties in an arid riparian forest of Hormozgan Province,Iran

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Journal of Arid Land 2022年第10期14卷 1099-1108页

作者： Maryam MOSLEHI JOUYBARI Asgahr BIJANI Hossien PARVARESH ross SHACKLETON Akram AHMADI Research Division of Natural Resources Hormozgan Agricultural and Natural Resources Research and Education CenterAgricultural ResearchEducation and Extension Organization(AREEO)Bandar Abbas ***Iran Department of Environmental Sciences Bandar Abbas BranchIslamic Azad UniversityBandar Abbas ***Iran Swiss Federal Institute for Forest Snow and Landscape Research(WSL)Birmensdorf 8903Switzerland Centre for Invasion Biology Department of Botany&ZoologyStellenbosch UniversityStellenbosch 7602South Africa Research Division of Natural Resources Golestan Agricultural and Natural Resources Research and Education CenterAgricultural ResearchEducation and Extension Organization(AREEO)Gorgan ***Iran

Biological invasions can alter soil properties within the range of their introduced,leading to impacts on ecosystem services,ecosystem functions,and *** better understand the impacts of biological invasions on soil,we compared topsoil physiochemical properties at sites with invasive alien tree species(Prosopis juliflora),native tree species(Prosopis cineraria,Acacia tortilis,and Acacia ehrenbergiana),and mixed tree species in Hormozgan Province of Iran in May *** this study,we collected 40 soil samples at a depth of 10 cm under single tree species,including ***,***,***,and ***,as well as under mixed tree *** results showed that organic matter,moisture,potassium,calcium,nitrogen,and magnesium in topsoil at sites with *** and *** growing in combination with *** were higher than that at sites where *** was present(P<0.05).Sodium at sites with *** and *** growing in combination with *** and *** was lower as compared to that at sites with just *** and *** conductivity was lower at sites with *** and *** growing in combination with ***,and it was higher at sites with mixed Acacia and *** *** on the generally more positive effect of native Acacia and *** on topsoil physiochemical properties as compared to the ***,afforestation with native tree species is preferable for soil *** addition,due to the negative effects of *** on soil properties,*** spread should be better managed.

关键词： Prosopis juliflora Prosopis cineraria tree species invasion topsoil physiochemical properties Iran

Impact of source tissue and ex vivo expansion on the characterization of goat mesenchymal stem cells

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Journal of Animal Science and Biotechnology 2015年第2期6卷 230-251页

作者： Nuradilla Mohamad-Fauzi Pablo J ross Elizabeth A Maga James D Murray Department of Animal Science University of California Institute of Ocean and Earth Sciences University of Malaya Department of Population Health and Reproduction University of California

Background： There is considerable interest in using goats as models for genetically engineering dairy animals and also for using stem cells as therapeutics for bone and cartilage repair. Mesenchymal stem cells （MSCs） have been isolated and characterized from various species, but are poorly characterized in goats. Results： Goat MSCs isolated from bone marrow （BM-MSCs） and adipose tissue （ASCs） have the ability to undergo osteogenic, adipogenic and chondrogenic differentiation. Cytochemical staining and gene expression analysis show that ASCs have a greater capacity for adipogenic differentiation compared to BM-MSCs and fibroblasts. Different methods of inducing adipogenesis also affect the extent and profile of adipogenic differentiation in MSCs. Goat fibroblasts were not capable of osteogenesis, hence distinguishing them from the MSCs. Goat MSCs and fibroblasts express CD90, CD105, CD73 but not CD45, and exhibit cytoplasmic localization of OCT4 protein. Goat MSCs can be stably transfected by Nucleofection, but, as evidenced by colony-forming efficiency （CFE）, yield significantly different levels of progenitor cells that are robust enough to proliferate into colonies of integrants following G418 selection. BM-MSCs expanded over increasing passages in vitro maintained karyotypic stability up to 20 passages in culture, exhibited an increase in adipogenic differentiation and CFE, but showed altered morphology and amenability to genetic modification by selection. Conclusions： Our findings provide characterization information on goat MSCs, and show that there can be significant differences between MSCs isolated from different tissues and from within the same tissue. Fibroblasts do not exhibit trilineage differentiation potential at the same capacity as MSCs, making it a more reliable method for distinguishing MSCs from fibroblasts, compared to cell surface marker expression.

关键词： Adipose Bone marrow Characterization Differentiation Goat Mesenchymal stem cells

Morality and modernity

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