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Current Zoology 2021年第5期67卷 519-530页

作者： Cintia Akemi OI Rafael Carvalho DA SILVA ian STEVEnS Helena Mendes FERREIRA Fabio Santos nASCIMEnTO Tom WEnSELEERS Laboratory of Socioecology and Social Evolution KU LeuvenLeuven 3000Belgium Faculdade de Filosofia Ciencias e Letras de Ribeirao PretoDepartamento de BiologiaUniversidade de Sao Paulo—USPRibeirao PretoSP 14040-901Brazil

In social insects,it has been suggested that reproduction and the production of particular fertilitylinked cuticular hydrocarbons(CHC)may be under shared juvenile hormone(JH)control,and this could have been key in predisposing such cues to later evolve into full-fledged queen pheromone ***,to date,only few studies have experimentally tested this“hormonal pleiotropy”***,we formally test this hypothesis using data from four species of Polistine wasps,Polistes dominula,Polistes satan,Mischocyttarus metathoracicus,and Mischocyttarus cassununga,and experimental treatments with JH using the JH analogue methoprene and the anti-JH *** line with reproduction being under JH control,our results show that across these four species,precocene significantly decreased ovary development when compared with both the acetone solvent-only control and the methoprene *** with the hormonal pleiotropy hypothesis,these effects on reproduction were further matched by subtle shifts in the CHC profiles,with univariate analyses showing that in *** and *** the abundance of particular linear alkanes and mono-methylated alkanes were affected by ovary development and our hormonal *** results indicate that in primitively eusocial wasps,and particularly in Polistes,reproduction and the production of some CHC cues are under joint JH *** suggest that pleiotropic links between reproduction and the production of such hydrocarbon cues have been key enablers for the origin of true fertility and queen signals in more derived,advanced eusocial insects.

关键词： Polistinae wasps fertility cues queen pheromones cuticular hydrocarbons juvenile hormone

Impaired gluconeogenesis in a porcine model of paracetamol induced acute liver failure

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World Journal of Gastroenterology 2011年第11期17卷 1457-1461页

作者： Konstantinos J Dabos Henry R Whalen Philip n newsome John A Parkinson neil C Henderson ian H Sadler Peter C Hayes John n Plevris Liver Cell Biology Laboratory Department of HepatologyUniversity of EdinburghEdinburghEH16 4SAUnited Kingdom Gastroenterology Unit Ioannina General Hospital Hatzikosta450-01 IoanninaGreece Gastroenterology Department Hatzikosta General HospitalLeoforos Makrygianni450-01 IoanninaGreece Department of Chemistry University of EdinburghEdinburghEH16 6AAUnited Kingdom

AIM:To investigate glucose homeostasis and in particular gluconeogenesis in a large animal model of acute liver failure(ALF).METHODS:Six pigs with paracetamol induced ALF under general anaesthesia were studied over 25 *** samples were withdrawn every five hours from a central *** animals were used as controls and were maintained under anaesthesia *** 1 H nMR spectroscopy we identified most gluconeogenic amino acids along with lactate and pyruvate in the animal plasma ***:no significant changes were observed in the concentrations of the amino acids studied in the animals maintained under anaesthesia *** we look at the ALF animals,we observed a statistically significant rise of lactate(Pnd pyruvate(Pnd of the *** also observed statistically significant rises in the concentrations of alanine(Pne(Pnine(Pne(Pnylalanine(Pnd isoleucine(Pne levels decreased significantly(PnCLUSIOn:Our pig model of ALF is characterized by an altered gluconeogenetic capacity,an impaired tricarboxylic acid(TCA)cycle and a glycolytic state.

关键词： Lactate Pyruvate Branch chain amino acids Aromatic amino acids

Isotopic and Petrographic Evidence as a Proxy in Paleoclimatic Reconstructions from Flowstones in Southern Spain

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Open Journal of Geology 2020年第6期10卷 597-611页

作者： Concepción Jiménez de Cisneros Antonio González-Ramón Cristina Sequero Bartolomé Andreo ian J. Fairchild Instituto Andaluz de Ciencias de la Tierra CSIC-UGR Granada Spain Instituto Geológico y Minero de Españ a IGME Granada Spain Departamento de Ciencias de la Tierra Universidad de Zaragoza Zaragoza Spain Departamento de Geología Centro de Hidrogeología Universidad de Málaga Campus de Teatinos Málaga Spain School of Geography Earth and Environmental Sciences University of Birmingham Birmingham UK

Changes in the morphology and mineralogy of speleothems (flowstones) clearly respond to climate-related phenomena, such as drip rate variability and temperature-modulated cave ventilation. Detailed petrographic observations have been coupled with nt-family:Verdana;white-space:normal;">nt-family:Verdana;white-space:normal;">δnt-family:Verdana;white-space:normal;">18O and δ13C values. Fabrics may show changes related to variations in supersaturation, drip rate or input of detrital particles or organic compounds. Fabrics formed under relatively constant and regular drips (columnar compact, open and elongated) show similar δ18O and δ13C values, which are more negative than those of micrite and microsparite. The combination of internal microstratigraphy studies and isotopic data (δ18O and δ13C) from two flowstones collected from two caves in the north of Almeria province (SE Spain), suggest a spectrum of environmental conditions ranging from wetter to drier periods. Both records constitute a very useful tool for screening and interpreting high-resolution paleoclimate reconstructions.

关键词： Speleothems Flowstones Fabrics Isotopic Characterization Cave Paleoclimatic Changes

Ammonia-oxidizing archaea and bacteria are structured by geography in biological soil crusts across north American arid lands

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Ecological Processes 2013年第1期2卷 98-107页

作者： Yevgeniy Marusenko Scott T Bates ian Anderson Shannon L Johnson Tanya Soule Ferran Garcia-Pichel School of Life Sciences Arizona State UniversityP.O.Box 874501TempeAZ 85287-4501USA Cooperative Institute for Researchin Environmental Sciences University of ColoradoBoulderCO80309USA Bioscience Division B-11Los Alamos National LaboratoryLos AlamosNM87545USA Department of Biology Indiana University-Purdue UniversityFort WayneINUSA

Introduction:Biological soil crusts(BSCs)can dominate surface cover in dry lands worldwide,playing an integral role in arid land biogeochemistry,particularly in n fertilization through fixation and *** is a characteristic and universal n transformation in BSCs that becomes important for the export of n beyond the microscopic bounds of the crust *** contribution of ammonia-oxidizing bacteria(AOB)in BSCs has been shown,but the role and extent of the recently discovered ammonia-oxidizing archaea(AOA)have ***:We sampled various types of crusts in four desert regions across the western United States and characterized the composition and size of ammonia-oxidizing communities using clone libraries and quantitative PCR targeting the amoA gene,which codes for the ammonia monooxygenase enzyme,universally present in ammonia-oxidizing ***:All archaeal amoA sequences retrieved from BSCs belonged to the Thaumarchaeota(nitrososphaera associated Group I.1b).Sequences from the Sonoran Desert,Colorado Plateau,and Great Basin were indistinguishable from each other but distinct from those of the Chihuahuan *** on amoA gene abundances,archaeal and bacterial ammonia oxidizers were ubiquitous in our survey,but the ratios of archaeal to bacterial ammonia oxidizers shifted from bacterially dominated in northern,cooler deserts to archaeally dominated in southern,warmer ***:Archaea are shown to be potentially important biogeochemical agents of biological soil crust n *** associated with different types of BSCs and biogeographical factors reveal a niche differentiation between AOA and AOB,possibly driven by temperature.

关键词： Biological soil crust Desert Arid amoA Ammonia oxidation nitrification nitrogen cycle Thaumarchaeota

Single-center experience with radium-223 in patients with castration-resistant prostate cancer and bone metastases

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Asian Journal of Andrology 2020年第4期22卷 437-438页

作者： Anil Kapoor nathan C Wong Yuding Wang Som Mukherjee Sebastien Hotte ian Dayes Himu Lukka Division of Urology Department of SurgeryMcMaster UniversityHamiltonON L8N 4A6U SA Department of Oncology McMaster UniversityHamiltonON L8N 4A6USA.

Dear Editor,Approximately 90%of men with metastatic castration-resistant prostate cancer(mCRPC)have bone metastases that can cause excruciating pain,bone fractures,disability,and death.13 Radium-223 is a radioactive isotope that mimics calcium and emits alpha particle radiation that selectively targets bone metastases.4,5 The results from the Alpharadin in Symptomatic Prostate Cancer Patients(ALSYMPCA)study,a phase 3 randomized controlled trial,showed that radium-223 improved overall survival(OS)and time to symptomatic skeletalrelated events(SRE)in men with mCRPC and bone metastases compared to placebo.6 Despite the FDA approval,radium-223 appears to be less utilized for the treatment of mCRPC compared to oral agents that target the androgen receptor pathway.

关键词： metastases cancer Cancer

Dry sliding tribological behavior of Zr-based bulk metallic glass

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Transactions of nonferrous Metals Society of China 2012年第3期22卷 585-589页

作者：吴宏 ian BAKER 刘咏吴晓蓝中南大学粉末冶金国家重点实验室 Thayer School of Engineering Dartmouth CollegeHanoverNH 03755-8000U.S.A

The tribological behavior of a Zr-based bulk metallic glass（BMG） was investigated using pin-on-disk sliding measurements in two different environments,i.e.,air and argon,against an yttria-stabilized zirconia *** was found that the wear of the Zr-based BMG was reduced by more than 45% due to the removal of oxygen from the test environment at two different loads,i.e.,16 n and 23 *** wear pins were examined using X-ray diffractometry,differential scanning calorimetry,scanning electron microscopy and optical surface profilometry.A number of abrasive particles and grooves presented on the worn surface of the pin tested in air,while a relatively smooth worn surface was observed in the specimens tested in *** wear mechanism of the pin worn in air was dominated by abrasive wear compared with an adhesive wear controlled process in the tests performed in argon.

关键词： bulk metallic glasses tribological behavior oxidation wear mechanism

Sex ratio of mirid populations shifts in response to hostplant co-infestation or altered cytokinin signaling

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Journal of Integrative Plant Biology 2017年第1期59卷 44-59页

作者： nora Adam Theresa Erler Mario Kallenbach Martin Kaltenpoth Grit Kunert ian T.Baldwin Meredith C.Schuman Department of Molecular Ecology Max Planck Institute for Chemical Ecology Hans-Knoll-Straβe 8 07745 Jena Germany German Centre for Integrative Biodiversity Research (iDiv) Deutscher Platz5e 04103 Leipzig Germany Max Planck Research Group Insect Symbiosis Max Planck Institute for Chemical Ecology Hans-Knoll-Straβe 8 07745 Jena Germany Department of Biochemistry Max Planck Institute for Chemical Ecology Hans-Knoll-Straβe 8 07745 Jena Germany

Herbivore species sharing a host plant often compete. In this study, we show that host plant-mediated interaction between two insect herbivores-a generalist and a specialist-results in a sex ratio shift of the specialist＇s offspring. We studied demographic parameters of the specialist Tupiocoris notatus（Hemiptera： Miridae）when co-infesting the host plant nicotiana attenuata（Solanaceae） with the generalist leafhopper Empoasca sp.（Hemiptera： Cicadellidae）. We show that the usually female-biased sex ratio of T. notatus shifts toward a higher male proportion in the offspring on plants coinfested by Empoasca sp. This sex ratio change did not occur after oviposition, nor is it due differential mortality of female and male nymphs. Based on pyrosequencing and PCR of bacterial 16 S rRnA amplicons, we concluded that sex ratio shifts were unlikely to be due to infection with Wolbachia or other known sex ratio-distorting endosymbionts. Finally, we used transgenic lines of *** to evaluate if the sex ratio shift could be mediated by changes in general or specialized host plant metabolites. We found that the sex ratio shift occurred on plants deficient in two cytokinin receptors（irCHK2/3）.Thus, cytokinin-regulated traits can alter the offspring sex ratio of the specialist ***.

关键词： Empoasca populations specialist offspring Hemiptera altered nicotiana specialized Solanaceae transgenic

Collective Perspective on Advances in Dyson–Schwinger Equation QCD

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Communications in Theoretical Physics 2012年第7期58卷 79-134页

作者： Adnan Bashir ian C.Clet Bruno El-Bennich Craig D.Roberts Peter C.Tandy Instituto de Física y Matemticas Universidad Michoacana de San Nicols de Hidalgo Edificio C-3Ciudad UniversitariaMoreliaMichoacn 58040Mxico Physics Division Argonne National Laboratory ArgonneIllinois 60439USA Center for nuclear Research Department of PhysicsKent State UniversityKent OH 44242USA CSSM and CoEPP School of Chemistry and Physics University of AdelaideAdelaide SA 5005Australia Laboratorio de Física Teórica e Computao Científica Universidade Cruzeiro do Sul01506-000 So PauloSPBrazil Instituto de Física Torica Universidade Estadual Paulista01140-070 So PauloSPBrazil Department of Physics Center for High Energy Physics and State Key Laboratory of Nuclear Physics and TechnologyPeking University Institut für Kernphysik Forschungszentrum JülichD-52425 JülichGermany Department of Physics Illinois Institute of TechnologyChicagoIllinois 60616-3793USA

We survey contemporary studies of hadrons and strongly interacting quarks using QCD's Dyson-Schwinger equations, addressing the following aspects: confinement and dynamical chiral symmetry breaking; the hadron spectrum; hadron elastic and transition form factors, from small-to large-Q2; parton distribution functions; the physics of hadrons containing one or more heavy quarks; and properties of the quark gluon plasma.

关键词： confinement dynamical chiral symmetry breaking Dyson-Schwinger equations hadron spectrum hadron elastic and transition form factors heavy mesons in-hadron condensates parton distribution functions quark gluon plasma UA(1)-problem

Stable isotope analysis of diet confirms niche separation of two sympatric species of namib Desert lizard

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Integrative Zoology 2016年第1期11卷 60-75页

作者： ian W.MURRAY Hilary M.LEASE Robyn S.HETEM Duncan MITCHELL Andrea FULLER Stephan WOODBORnE Brain Function Research Group School of PhysiologyFaculty of Health SciencesUniversity of the WitwatersrandJohannesburgSouth Africa Biology Department Whitman CollegeWalla WallaWashingtonUSA iThemba Laboratories GautengSouth Africa Stable Isotope Laboratory Mammal Research InstituteDepartment of Zoology and EntomologyUniversity of PretoriaPretoriaSouth Africa

We used stable isotopes of carbon and nitrogen to study the trophic niche of two species of insectivorous lizards,the Husab sand lizard Pedioplanis husabensis and Bradfield’s namib day gecko living sympatrically in the namib *** measured theδ13C andδ15n ratios in lizard blood tissues with different turnover times(whole blood,red blood cells and plasma)to investigate lizard diet in different *** also measured theδ13C andδ15n ratios in available arthropod prey and plant tissues on the site,to identify the avenues of nutrient movement between lizards and their *** the use of stable isotope mixing models,we found that the two lizard species relied on a largely non-overlapping but seasonally variable array of arthropods:*** primarily fed on termites,beetles and wasps,while *** fed mainly on ants,wasps and *** originating from C3 plants were proportionally higher for *** than for *** during autumn and late autumn/early winter,although not *** to the few available data estimating the trophic transfer of nutrients in ectotherms in mixed C3 and C4/crassulacean acid metabolism(CAM)plant landscapes,we found that our lizard species primarily acquired nutrients that originated from C4/CAM *** work adds an important dimension to the general lack of studies using stable isotope analyses to estimate lizard niche partitioning and resource use.

关键词： namib Desert niche partitioning Pedioplanis Rhoptropus stable isotopes