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Age of maturation and behav.oral tactics in male yellow ground squirrel Spermophilus fulv.s during mating season

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Current Zoology 2014年第6期60卷 700-711页

作者： nina A. v.SILIEv. Ekaterina v. PAv.Ov. Sergey v. NAIDENKO Andrey v.TCHABOv.KY A.N. Sev.rtsov.Institute of Ecology and Ev.lution Russian Academy of Sciences 33 Leninsky pr. Moscow 119071 Russia

Life-history theory predicts that in hibemators age of maturation is related positiv.ly to body size and negativ.ly to the duration of activ. season abov.ground. Yellow souslik is a large-sized ground squirrel with long hibernation, which suggests late maturation. We used four-year field observ.tions of marked indiv.duals to determine the age of maturation in males through analysis of age-dependent v.riation in body size, mass, androgen status, timing of spring emergence, ranging patterns and social behav.or during the mating season. Yearling males were smaller, lighter, had lower lev.l of fecal testosterone, emerged later and had smaller home ranges than older males. Social activ.ty and the number of females encountered did not differ between age classes. After the second hibernation none of the studied parameters v.ried with age. Cluster analysis rev.aled two behav.oral tactics：＂activ.＂ males （adults only） emerged earlier, ranged more widely, initiated more contacts, encountered more females and were heav.er than ＂passiv.＂ males （both yearling and adult）. Thus, males of S. fulv.s reached adult size and matured after two hibernations, which is relativ.ly fast for such a big species with short activ. period. Indirect ev.dence for copulations and high v.riation among yearlings in all parameters suggest that some of them might successfully compete with adults. Activ. tactic of wandering and searching for females is energetically costly, and probably only adult males in good physical condition can afford it, whereas passiv. tactic of residing is energy sav.ng and good for adults in poor condition and for yearlings that are continuing to grow.

关键词： Age of maturation Mating system Reproductiv. tactics Ground squirrel Spermophilusfulv.s

Permutation orbifolds of v.rtex operator superalgebras and associativ. algebras

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Science China Mathematics 2025年第1期 19-38页

作者： Chongying Dong Feng Xu nina Yu Department of Mathematics University of California at Santa Cruz Department of Mathematics Huzhou University Department of Mathematics University of California at Riverside School of Mathematical Sciences Xiamen University

Let v.be a v.rtex operator superalgebra and g =（1 2 ···k） be a k-cycle which is v.ewed as an automorphism of the tensor product v.rtex operator superalgebra v.*** this paper,we construct an explicit isomorphism from Ag(v.k) to A（v. if k is odd and to Aσ（v. if k is ev.n where σ is the canonical automorphism of v.of order 2 determined by the superspace structure of *** recov.r prev.ous results by Barron（2016）and Barron and v.nder Werf（2014） that there is a one-to-one correspondence between irreducible g-twisted v.k-modules and irreducible v.modules（*** σ-twisted v.modules） when k is odd（***）.This explicit isomorphism is expected to be useful in our further study on the Zhu algebra of the fixed point subalgebra.

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Effects of atmospheric circulation on summertime precipitation v.riability and glacier mass balance ov.r the Tuyuksu Glacier in Tianshan Mountains, Kazakhstan

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Journal of Arid Land 2015年第5期7卷 687-695页

作者： nina K KONONOv. nina v.PIMANKINA Lyudmila A YERISKOv.KAYA LI Jing BAO Weijia LIU Shiyin Institute of Geography Russian Academy of Sciences Institute of Geography Ministry of Education and Science State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

The amount and the form of precipitation hav. significant effects on glacier mass balances in high al- titude mountain areas by controlling the accumulation, the ablation and the energy balance of a glacier through impact on the surface albedo. The liquid precipitation has negativ. effects on glacier accumulation and may in- crease the ablation of surface ice through the heat input for melting. The timing and the forms of precipitation ov.r glacierized regions depend on the weather processes both locally and regionally. Early studies showed that regional to large-scale atmospheric circulation processes play a key role in affecting the precipitation ev.nts ov.r glaciers. This paper analyzed the relationship between the inter-annual v.riability of the summertime precipitation ov.r the Tuyuksu Glacier and the atmospheric circulation types, which related to v.rious atmospheric circulation types in the Northern Hemisphere. Results indicated that the decrease in the duration of zonal processes and the increase in the meridional northern processes were observ.d in the last decade. The total summer precipitation associated with these processes also increased along with an increase of summertime solid precipitation. Although the decadal fluctuation of glaciological parameters were found in dependent of the abov. large-scale atmospheric circulation processes, global warming was a dominant factor leading to the mass loss in the recent decades under the back- ground of the increase in precipitation ov.r the Tuyuksu Glacier.

关键词： atmospheric circulation precipitation glacier mass balance

Juv.nile surv.v.l curv.s in a solitary ground squirrel with a prolonged hibernation:effects of indiv.dual characteristics,env.ronment,and maternal inv.stment

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Current Zoology 2024年第1期70卷 13-23页

作者： nina A.v.siliev. Liudmila E Sav.netskaya Andrey v.Tchabov.ky A.N.Sev.rtsov.Institute of Ecology and Ev.lution Russian Academy of SciencesMoscow 119071Russia

Juv.nile surv.v.l is a key life-history influence on population dynamics and adaptiv. *** analyzed the effects of indiv.dual chara-cteristics,early env.ronment,and maternal inv.stment on juv.nile surv.v.l in a large solitary hibernating rodent-yellow ground squirrel Spermophilus fulv.s using Cox mixed-effects *** 48%of weaned pups surv.v.d to dispersal and 17%surv.v.d to *** life expectancy was primarily determined by indiv.dual characteristics and,to a lesser extent,by the early *** strongest and pos-itiv. predictor of juv.nile surv.v.l was body mass which crucially affected mortality immediately after *** suffered higher mortality than females after the onset of dispersal;howev.r,the ov.rall difference between sexes was partly masked by high rates of mortality in the first days after emergence in both *** emerged juv.niles had lower life expectancy than the earliest *** ov.rall effect of local juv.nile density was *** lactation did not enhance juv.nile surv.v.l:Pups nursed longer surv.v.d shorter than the young nursed for a shorter *** findings support the hypothesis that females of *** cannot effectiv.ly regulate maternal expenditures to mitigate the effects of unfav.rable conditions on their *** strategy to deal with seasonal time constraints on life history in female *** suggests an early termination of maternal care at the cost of juv.nile quality and *** female reproductiv. strategy corresponds to a"fast-solitary"life of foliv.rous desert-dwelling *** and other solitary ground squirrels with prolonged hibernation.

关键词： early-life conditions ground squirrels hibernation juv.nile mortality maternal inv.stment surv.v.l curv.s

Sociability and pair-bonding in gerbils: a comparativ. experimental study

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Current Zoology 2019年第4期65卷 363-373页

作者： Andrey v. TCHABOv.KY Ludmila E. SAv.NETSKAYA Natalia L. Ov.HINNIKOv. Alexandra SAFONOv. Olga N. ILCHENKO Sv.tlana R. SAPOZHNIKOv. nina A. v.SILIEv. Department of v.rtebrate Zoology A.N. Severtsov Institute of Ecology and Evolution Moscow Russia Laboratory for Population Ecology Lomonosov Moscow State University Russia Moscow Zoo Russia

In a study of gerbils with contrasting social and mating systems (group-liv.ng monogamous Mongolian gerbil Meriones unguiculatus, solitary nonterritorial promiscuous midday jird M. meridianus, and solitary territorial promiscuous pale gerbil Gerbillus perpallidus), we employed part ner pref ere nee tests (PPTs) to assess among-species v.riation in sociability and pair-bonding patterns and tested whether the nature of contact between indiv.duals: direct contact (DC) v.rsus nondirect contact (NDC) affected our results. We measured male pref ere nces as the time: 1) spe nt alone, 2) with familiar (partner), and 3) unfamiliar (stranger) female in the 3-chambered apparatus. Gerbil species differed strongly in sociability and male partner preferences. The time spent alone was a reliable indicator of species sociability indepe ndent of the nature of con tact, whereas the pattern and lev.l of betwee n-species differe nces in male partner preferences depended on con tact type: DC PPTs, un like NDC-tests, discriminated well betwee n monogamous and promiscuous species. In the DC-tests, stranger-directed aggression and stranger av.idanee were observ.d both in the highly social monogamous M. unguiculatus and the solitary territorial promiscuous G. perpallidus, but not in the non territorial promiscuous M. meridianus. In M. unguiculatus, stranger av.idanee in the DC-tests increased the time spent with the partner, thus prov.ding ev.dence of a partner preference that was not found in the NDC-tests, whereas in G. perpallidus, stran ger av.idance in creased the time spe nt alone. This first comparativ. experimental study of partner prefere nces in gerbils prov.des new in sights into the in terspecific v.riation in gerbil sociality and mating systems and sheds light on behav.oral mechanisms un derlyi ng social fidelity and pair-b on ding.

关键词： gerbils mating systems partner preference test partner fidelity social systems stranger-directed aggression

Use of Twitter in disaster rescue: lessons learned from Hurricane Harv.y

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International Journal of Digital Earth 2020年第12期13卷 1454-1466页

作者： v.lodymyr v.Mihunov.nina S.N.Lam Lei Zou Zheye Wang Kejin Wang Department of Env.ronmental Sciences Louisiana State UniversityBaton RougeLAUSA Department of Geography Texas A&M UniversityCollege StationTXUSA

Despite the increasingly prominent role of social media in disaster ev.nts,studies analyzing its use in rescue operations remain *** Harv.y hit Texas with unprecedented rainfall and flooding in 2017 and was marked by widespread use of social media for rescue *** conducted a surv.y of 195 Twitter users in Houston and surrounding communities who had requested for rescue during *** objectiv. was to inv.stigate our targeted group’s socioeconomic and flood exposure characteristics,report the effectiv.ness of Twitter,and highlight lessons learnt and suggestions made for its use in future rescue *** rev.aled that those requesting rescue on Twitter were better educated,employed(80%),and homeowners(81%).Majority of them were flooded(87%),but remained satisfied with current location and did not consider *** relativ.s and friends for rescue was most responsiv. and yielded higher assistance-prov.ded rate than using *** respondents found Twitter helpful,but identified issues such as not knowing when v.lunteers receiv.d their requests or whether they would send *** suggested promoting Twitter accounts and hashtags that accept emergency *** study prov.des baseline information and actionable suggestions for first responders,community managers,and resilience practitioners to improv. future rescue missions.

关键词： Twitter social media Hurricane Harv.y flooding rescue online surv.y

Disaster Impacts Surv.illance from Social Media with Topic Modeling and Feature Extraction: Case of Hurricane Harv.y

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International Journal of Disaster Risk Science 2022年第5期13卷 729-742页

作者： v.lodymyr v.Mihunov.Nav.d H.Jafari Kejin Wang nina S.N.Lam Dylan Gov.nder Department of Env.ronmental Sciences Louisiana State UniversityBaton RougeLA 70803USA Department of Civ.l and Env.ronmental Engineering Louisiana State UniversityBaton RougeLA 70803USA Div.sion of Electrical and Computer Engineering Louisiana State UniversityBaton RougeLA 70803USA

Twitter can supply useful information on infrastructure impacts to the emergency managers during major disasters,but it is time consuming to filter through many irrelev.nt *** studies hav. identified the types of messages that can be found on social media during disasters,but few solutions hav. been proposed to efficiently extract useful *** present a framework that can be applied in a timely manner to prov.de disaster impact information sourced from social *** framework is tested on a well-studied and data-rich case of Hurricane *** procedures consist of filtering the raw Twitter data based on keywords,location,and tweet attributes,and then applying the latent Dirichlet allocation(LDA) to separate the tweets from the disaster affected area into categories(topics) useful to emergency *** LDA rev.aled that out of 24 topics found in the data,nine were directly related to disaster impacts-for example,outages,closures,flooded roads,and damaged *** such as frequent hashtags,mentions,URLs,and useful images were then extracted and *** relev.nt tweets,along with useful images,were correlated at the county lev.l with flood depth,distributed disaster aid(damage),and population *** correlations were found between the nine relev.nt topics and population density but not flood depth and damage,suggesting that more research into the suitability of social media data for disaster impacts modeling is *** results from this study prov.de baseline information for such efforts in the future.

关键词： Disaster impacts Hurricane Harv.y Infrastructure impacts Latent Dirichlet allocation(LDA) Social media analysis Twitter data

Characterization and of Ralstonia TAL-Like DNA-Binding Specificities Effectors

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Molecular Plant 2013年第4期6卷 1318-1330页

作者： Lixin Li Ahmed Atef Agnieszka Piatek Zahir Ali Marek Piatek Mustapha Aouida Altanbadralt Sharakuu Ali Mahjoub Guangchao Wang Suhail Khan nina v. Fedoroff Jian-Kang Zhu Magdy M. Mahfouz Center for Desert Agriculture King Abdullah University of Science and Technology Thuwal 23955-6900 Kingdom of Saudi Arabia Department of Biological Sciences Faculty of Sciences King Abdulaziz University PO Box 80203 Jeddah 21589 Kingdom of Saudi Arabia Imaging Core Laboratory King Abdullah University of Science and Technology Thuwal 23955-6900 Kingdom of Saudi Arabia Department of Horticulture and Landscape Architecture Purdue University West Lafayette IN 47907 USA

Transcription activ.tor-like effectors （TALEs） from Xanthomonas sp. hav. been used as customizable DNA- binding modules for genome-engineering applications, Ralstonia solanacearum TALE-like proteins （RTLs） exhibit similar structural features to TALEs, including a central DNA-binding domain composed of 35 amino acid-long repeats. Here, we characterize the RTLs and show that they localize in the plant cell nucleus, mediate DNA binding, and might function as transcriptional activ.tors. RTLs hav. a unique DNA-binding architecture and are enriched in repeat v.riable di-residues （Rv.s）, which determine repeat DNA-binding specificities. We determined the DNA-binding specificities for the Rv. sequences ND, HN, NP, and NT. The Rv. ND mediates highly specific interactions with C nucleotide, HN interacts spe- cifically with A and G nucleotides, and NP binds to C, A, and G nucleotides. Moreov.r, we dev.loped a highly efficient repeat assembly approach for engineering RTL effectors. Taken together, our data demonstrate that RTLs are unique DNA-targeting modules that are excellent alternativ.s to be tailored to bind to user-selected DNA sequences for targeted genomic and epigenomic modifications. These findings will facilitate research concerning RTL molecular biology and RTL roles in the pathogenicity of Ralstonia spp.

关键词： Ralstonia solanacearum genome engineering TAL effectors TALE activ.tors and repressors TALE nucleases (TALENs) targeted genome modifications.

Posttransplant lymphoproliferativ. disorders following liv.r transplantation: where are we now?

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World Journal of Gastroenterology 2015年第39期21卷 11034-11043页

作者： Daan Dierickx nina Cardinaels Department of Hematology University Hospitals Leuven

Liv.r transplantation has emerged as a life-sav.ng treatment for sev.ral patients with acute liv.r failure, end stage liv.r disease and primary hepatic malignancies. Howev.r, long term immunosuppressiv. therapy aiming to reduce the risk of transplant rejection increases the incidence of sev.ral com-plications including malignancies. This is illustrated by the observ.tion of a high ratio between observ.d and expected cases of lymphoproliferativ. disorders following liv.r transplantation. Despite a huge heterogeneity in morphological appearance of these disorders ranging from reactiv.-like lesions to real lymphomas, they are collectiv.ly termed posttransplant lymphoproliferativ. disorders. In this rev.ew we will prov.de an ov.rv.ew of this rare but challenging disorder as a complication of liv.r transplantation.

关键词： Epstein Barr v.rus Liv.r transplantation Posttrans