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Long-term monitoring of cycles in Clethrionomys rutilus in the Yukon boreal forest

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Integrative Zoology 2024年第1期19卷 27-36页

作者： charles J.KREbS Alice J.KENNEY b.Scott GILbERT Rudy bOONSTRA Department of Zoology University of British ColumbiaVancouverBritish ColumbiaCanada Renewable Resources Management Program Yukon UniversityWhitehorseYukonCanada Department of biological Sciences University of Toronto ScarboroughTorontoOntarioCanada

baseline studies of small rodent populations in undisturbed ecosystems are *** report here 50 years of mon-itoring and experimentation in Yukon of a dominant rodent species in the North American boreal forest,the red-backed vole Clethrionomys *** voles breed in summer,weigh 20–25 g,and reach a maximum density of 20 to 25 per *** populations have shown consistent 3–4-year cycles for the last 50 years with the only change being that peak densities averaged 8/ha until 2000 and 18/ha since that *** the last 25 years,we have measured food resources,predator numbers,and winter weather,and for 1-year social interactions,to estimate their contribution to changes in the rate of summer increase and the rate of overwinter *** these potential limiting factors could contribute to changes in density,and we measured their relative contributions statistically with multiple *** rate of winter decline in density was related to both food supply and winter *** rate of summer increase was related to summer berry crops and white spruce cone *** measure of predator numbers was related to winter or summer changes in vole *** was a large signal of climate change effects in these *** is no density dependence in summer population growth and only a weak one in winter population *** of our results provide a clear understanding of what generates 3–4-year cycles in these voles,and the major missing piece may be an understanding of social interactions at high density.

关键词： boreal forest climate change density dependence population cycles predation winter severity

Synchronization and firing mode transition of two neurons in a bilateral auditory system driven by a high–low frequency signal

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Chinese Physics b 2024年第5期33卷 722-735页

作者： charles Omotomide Apata 唐浥瑞周祎凡蒋龙裴启明 School of Physics and Optoelectronic Engineering Yangtze UniversityJingzhou 434023China

The FitzHugh–Nagumo neuron circuit integrates a piezoelectric ceramic to form a piezoelectric sensing neuron,which can capture external sound signals and simulate the auditory neuron *** piezoelectric sensing neurons are coupled by a parallel circuit consisting of a Josephson junction and a linear resistor,and a binaural auditory system is *** the non-singleness of external sound sources,the high–low frequency signal is used as the input signal to study the firing mode transition and synchronization of this *** is found that the angular frequency of the high–low frequency signal is a key factor in determining whether the dynamic behaviors of two coupled neurons are *** they are in synchronization at a specific angular frequency,the changes in physical parameters of the input signal and the coupling strength between them will not destroy their *** addition,the firing mode of two coupled auditory neurons in synchronization is affected by the characteristic parameters of the high–low frequency signal rather than the coupling *** asynchronous dynamic behavior and variations in firing modes will harm the auditory *** findings could help determine the causes of hearing loss and devise functional assistive devices for patients.

关键词： piezoelectric ceramic Josephson junction auditory neuron synchronization

bulk geochemistry,Rb-Sr,Sm-Nd,and stable O-H isotope systematics of the Metzimevin high-grade iron ore deposit,Mbalam iron ore district,southern Cameroon

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Acta Geochimica 2024年第4期43卷 677-706页

作者： Samndong Cyril Tufoin Cheo Emmanuel Suh Tabod charles Tabod George Lemewihbwen Ngiamte Department of Geology Mining and Environmental ScienceThe University of BamendaB.P.39BambiliNorth West RegionCameroon Economic Geology Unit Department of GeologyUniversity of BueaP.O.63BueaSouth West RegionCameroon Department of Physics Faculty of ScienceThe University of BamendaB.P.39BambiliNorth West RegionCameroon Department of Geology Pan-African University Life and Earth Sciences Institute(PAULESI)University of IbadanIbadanNigeria

bulk geochemistry,Sr,Nd,and O-H isotope systematics are reported for the first time on banded iron formation(bIF)-hosted high-grade iron ore at the northwestern segment of Congo Craton(CC).Located in Mbalam iron ore district,Southern Cameroon,Metzimevin iron ore deposit is a hematite-magnetite bIF system,dominated by SiO_(2)+Fe_(2)O_(3)(97.1 to 99.84 wt%),with low concentrations of clastic elements e.g.,Al_(2)O_(3),TiO_(2),and HFSE,depicting a nearly pure chemical *** REE+Y signature of the iron deposit displays strong positive Eu anomaly,strong negative Ce anomaly,and chondritic to superchondritic Y/Ho ratios,suggestive of formation by mixed seawater-high temperature hydrothermal fluids in oxidising ***^(87)Sr/^(86)Sr ratios of the bIF are higher than the maximum^(87)Sr/^(86)Sr evolution curves for all Archean reservoirs(bulk silicate earth,Archean crust and Archean seawater),indicating involvement of continentally-derived components during bIF formation and ***Ɛ_(Nd)(t)(+2.26 to+3.77)and Nd model age indicate that chemical constituents for the bIF were derived from undifferentiated crustal source,between 3.002 and 2.88 *** variable and diverse O and H isotope data(−1.9‰to 17.3‰and−57‰to 136‰respectively)indicate that the Metzimevin iron ore formed initially from magmatic plumes and later enriched by magmatic-metamorphic-modified meteoric *** balance calculations indicate mineralisation by combined leaching and precipitation,with an average iron enrichment factor of>2.67 and SiO_(2)depletion factor of>*** is associated with an overall volume reduction of 28.27%,reflecting net leaching and volume collapse of the bIF protholith.

关键词： bulk geochemistry Rb-Sr Sm-Nd Mitzimevin High-grade iron ore

Pleistocene glaciation advances the cryptic speciation of Stellera chamaejasme *** a major biodiversity hotspot

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Journal of Integrative Plant biology 2024年第6期66卷 1192-1205页

作者： Santosh Kumar Rana Hum Kala Rana Jacob bLandis Tianhui Kuang Juntong Chen Hengchang Wang Tao Deng charles C.Davis Hang Sun CAS Key Laboratory for Plant Diversity and biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Arkansas biosciences Institute Arkansas State UniversityJonesboroArkansas 72401USA School of Integrative Plant Science Section of Plant Biology and the L.H.Bailey HortoriumCornell UniversityIthacaNew York 14853USA bTI Computational biology Center Boyce Thompson InstituteIthacaNew York 14853USA CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Chinese Academy of SciencesWuhan Botanical GardenWuhan 430074China Department of Organismic and Evolutionary biology HerbariaHarvard UniversityCambridgeMassachusetts 02138USA

The mountains of Southwest China comprise a significant large mountain range and biodiversity hotspot imperiled by global climate *** high species diversity in this mountain system has long been attributed to a complex set of factors,and recent large-scale macroevolutionary investigations have placed a broad timeline on plant diversification that stretches from 10 million years ago(Mya)to the *** our increasing understanding of the temporal mode of speciation,finer-scale populationlevel investigations are lacking to better refine these temporal trends and illuminate the abiotic and biotic influences of cryptic *** is largely due to the dearth of organismal sampling among closely related species and populations,spanning the incredible size and topological heterogeneity of this *** study dives into these evolutionary dynamics of speciation using genomic and ecomorphological data of Stellera chamaejasme *** identified four previously unrecognized cryptic species having indistinct morphological traits and large metapopulation of evolving lineages,suggesting a more recent diversification(~2.67-0.90 Mya),largely influenced by Pleistocene glaciation and biotic *** factors likely influenced allopatric speciation and advocated cyclical warming–cooling episodes along elevational gradients during the *** study refines the evolutionary timeline to be much younger than previously implicated and raises the concern that projected future warming may influence the alpine species diversity,necessitating increased conservation efforts.

关键词： cryptic speciation glacial-interglacial Hengduan Mountains north-south migration Stellera chamaejasme

Temporal trends and practice variation of paediatric diagnostic tests in primary care:retrospective analysis of 14 million tests

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Family Medicine and Community Health 2024年第4期12卷 1-8页

作者： Elizabeth T Thomas Diana R Withrow Cynthia wright Drakesmith Peter J Gill Rafael Perera-Salazar Carl Heneghan Centre for Evidence-based Medicine Nuffield Department of Primary Care Health SciencesUniversity of OxfordOxfordUK Nuffield Department of Primary Care Health Sciences University of OxfordOxfordUK Department of Pediatrics University of TorontoTorontoOntarioCanada Hospital for Sick Children TorontoOntarioCanada

Objective The primary objective was to investigate temporal trends and between-practice variability of paediatric test use in primary *** and analysis This was a descriptive study of population-based data from Clinical Practice Research Datalink Aurum primary care consultation records from 1 January 2007 to 31 December *** aged 0–15 who were registered to one of the eligible 1464 general practices and had a diagnostic test code in their clinical record were *** primary outcome measures were(1)temporal changes in test rates measured by the average annual percent change,stratified by test type,gender,age group and deprivation level and(2)practice variability in test use,measured by the coefficient of *** 14299598 diagnostic tests were requested over 27.8 million child-years of observation for 2542101 *** test use increased by 3.6%/year(95%CI 3.4 to 3.8%)from 399/1000 child-years to 608/1000 child-years,driven by increases in blood tests(8.0%/year,95%CI 7.7 to 8.4),females aged 11–15(4.0%/year,95%CI 3.7 to 4.3),and children from the most socioeconomically deprived group(4.4%/year,95%CI 4.1 to 4.8).Tests subject to the greatest temporal increases were faecal calprotectin,fractional exhaled nitric oxide and vitamin *** classified as high-use and high-practice variability were iron studies,coeliac testing,vitamin b12,folate,and vitamin *** In this first nationwide study of paediatric test use in primary care,we observed significant temporal increases and practice variability in *** reflects inconsistency in practice and diagnosis rates and a scarcity of evidence-based *** test use generates more clinical activity with significant resource implications but conversely may improve clinical *** research should evaluate whether increased test use and variability are warranted by exploring test indications and test results and directly examine how increased test use impacts

关键词： vitamin nationwide stratified

Aging impairs the osteocytic regulation of collagen integrity and bone quality

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bone Research 2024年第1期12卷 78-94页

作者： charles A.Schurman Serra Kaya Neha Dole Nadja M.Maldonado Luna Natalia Castillo Ryan Potter Jacob P.Rose Joanna bons Christina D.King Jordan b.burton birgit Schilling Simon Melov Simon Tang Eric Schaible Tamara Alliston Department of Orthopaedic Surgery University of CaliforniaSan FranciscoCA 94143USA UC berkeley/UCSF Graduate Program in bioengineering San FranciscoCA 94143USA buck Institute for Research on Aging NovatoCA 94945USA Washington University in St Louis Department of OrthopedicsSt.LouisMO 63130USA Advanced Light Source Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Poor bone quality is a major factor in skeletal fragility in elderly *** molecular mechanisms that establish and maintain bone quality,independent of bone mass,are unknown but are thought to be primarily determined by *** hypothesize that the age-related decline in bone quality results from the suppression of osteocyte perilacunar/canalicular remodeling(PLR),which maintains bone material *** examined bones from young and aged mice with osteocyte-intrinsic repression of TGFβsignaling(TβRII^(ocy−/−))that suppresses *** control aged bone displayed decreased TGFβsignaling and PLR,but aging did not worsen the existing PLR suppression in male TβRII^(ocy−/−)*** relationship impacted the behavior of collagen material at the nanoscale and tissue scale in macromechanical *** effects of age on bone mass,density,and mineral material behavior were independent of osteocytic TGFβ.We determined that the decline in bone quality with age arises from the loss of osteocyte function and the loss of TGFβ-dependent maintenance of collagen integrity.

关键词： maintain primarily integrity

Simultaneous determination of typical toxic aldehydes formed during food frying and digestion using isotope dilution UHPLC-QqQ-MS/MS

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Grain & Oil Science and Technology 2024年第1期7卷 42-49页

作者： Feng Wang Yun Cui Dongjie Liu charles brennan Soottawat benjakul Weiwei Cheng Gengsheng Xiao Lukai Ma Key Laboratory of Green Processing and Intelligent Manufacturing of Lingnan Specialty Food of Ministry and Rural Affairs College of Light Industry and FoodZhongkai University of Agriculture and EngineeringGuangzhou 510225China School of Science Royal Melbourne Institute of Technology UniversityMelbourneAustralia International Center of Excellence in Seafood Science and Innovation Faculty of Agro-IndustryPrince of Songkla UniversitySongkhla 90110Thailand College of Food Science and Technology Zhejiang University of TechnologyHangzhou 310014China

An isotope dilution ultra-performance liquid chromatography-triple quadrupole mass spectrometry method was developed to simultaneously detect two typical kinds ofα,β-unsaturated aldehydes,namely 4-hydroxy-2-hexenal(4-HHE)and 4-hydroxy-2-nonenal(4-HNE),in *** proposed method exhibited a linear range of 10-1000 ng/mL with a limit of detection of 0.1-2.0 ng/g and a limit of quantification of 0.3-5.0 ng/*** recovery rates of these typical toxic aldehydes(i.e.,4-HHE,4-HNE)and their d3-labeled analogues were 91.54%-105.12%with a low matrix ***,this proposed method was successfully applied to a real frying system and a simulated digestion system,wherein the contents of 4-HHE and 4-HNE were determined for ***,the obtained results provide strong support for further research into the production of 4-HHE and 4-HNE resulting from foods during oil digestion and frying.

关键词： UHPLC-QqQ-MS/MS 4-Hydroxy-2-hexenal 4-Hydroxy-2-nonenal Frying Simulated digestion

Intravenous immune globulin suppresses angiogenesis in mice and humans

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Signal Transduction and Targeted Therapy 2016年第1期1卷 141-148页

作者： Reo Yasuma Valeria Cicatiello Takeshi Mizutani Laura Tudisco Younghee Kim Valeria Tarallo Sasha bogdanovich Yoshio Hirano Nagaraj Kerur Shengjian Li Tetsuhiro Yasuma benjamin J Fowler charles b wright Ivana Apicella Adelaide Greco Arturo brunetti balamurali K Ambati Sevim barbasso Helmers Ingrid E Lundberg Ondrej Viklicky Jeanette HW Leusen J Sjef Verbeek bradley D Gelfand Ana bastos-Carvalho Sandro De Falco Jayakrishna Ambati Department of Ophthalmology and Visual Sciences University of KentuckyLexingtonKYUSA Department of Ophthalmology Nagoya University Graduate School of MedicineNagoyaJapan Angiogenesis Lab Institute of Genetics and Biophysics—CNRNaplesItaly bio-Ker MultiMedica GroupNaplesItaly Department of Physiology University of KentuckyLexingtonKYUSA Department of Advanced biomedical Sciences University of Naples‘Federico II’NaplesItaly CEINGE—biotecnologie Avanzate s.c.ar.l.NaplesItaly Department of Ophthalmology and Visual Sciences Moran Eye CenterUniversity of Utah School of MedicineSalt Lake CityUTUSA Department of Ophthalmology Veterans Affairs Salt Lake City Healthcare SystemSalt Lake CityUTUSA Rheumatology Unit Department of MedicineKarolinska InstitutetKarolinska University HospitalStockholmSweden Department of Nephrology Institute for Clinical and Experimental MedicinePrague 4Czech Republic Immunotherapy Laboratory Laboratory for Translational ImmunologyUniversity Medical Center UtrechtUtrechtThe Netherlands Department of Human Genetics Leiden University Medical CenterLeidenThe Netherlands Department of biomedical Engineering University of KentuckyLexingtonKYUSA Department of Microbiology Immunologyand Molecular GeneticsUniversity of KentuckyLexingtonKYUSA IRCCS MultiMedica MilanoItaly

Human intravenous immune globulin(IVIg),a purified IgG fraction composed of~60%IgG1 and obtained from the pooled plasma of thousands of donors,is clinically used for a wide range of *** biological actions of IVIg are incompletely understood and have been attributed both to the polyclonal antibodies therein and also to their IgG(IgG)Fc ***,we demonstrated that multiple therapeutic human IgG1 antibodies suppress angiogenesis in a target-independent manner via FcγRI,a high-affinity receptor for *** we show that IVIg possesses similar anti-angiogenic activity and inhibited blood vessel growth in five different mouse models of prevalent human diseases,namely,neovascular age-related macular degeneration,corneal neovascularization,colorectal cancer,fibrosarcoma and peripheral arterial ischemic *** was mediated by the Fc region of IVIg,required FcγRI and had similar potency in transgenic mice expressing human Fcγ***,IVIg therapy administered to humans for the treatment of inflammatory or autoimmune diseases reduced kidney and muscle blood vessel *** data place IVIg,an agent approved by the US Food and Drug Administration,as a novel angioinhibitory drug in doses that are currently administered in the clinical *** addition,they raise the possibility of an unintended effect of IVIg on blood vessels.

关键词： doses inhibited degeneration

Extinction of Light in the Galactic Halo: First Observational Evidence of the Interaction of Light and Dark Matter

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Journal of Modern Physics 2024年第8期15卷 1144-1198页

作者： charles H. McGruder III Department of Physics and Astronomy Western Kentucky University Bowling Green USA

We study the distribution of quasars on the celestial sphere according to ground-based SDSS and space-based WISE and Gaia observations. All distributions as a function of galactic latitude, b, exhibit a decrease in quasar frequency well outside the dust in and near the galactic plane. We prove that the observed decrease in quasar frequency at high galactic latitudes is not accompanied by reddening, meaning that it can not be caused by dust. The scattering of light by the circumgalactic gas is negligible because the Thomson scattering cross section is very small. We conclude the observed scattering of light must be caused by dark matter in the galactic halo. We determine the mass and charge of dark matter particles. If the dark matter particle is a fermion its mass, mDMand charge eDM=δe, where e is the elementary charge are: mDM=3.2×10−2eV and δ=3.856×10−5. If however the dark matter particle is spinless then: mDM=0.511eV and δ=2.132×10−4. These values for the charge of a dark matter particle are orders of magnitude higher than the upper limit of the neutrino charge according to laboratory experiments. Consequently, dark matter particles are not charged neutrinos. Since dark matter particles are charged, they must emit and absorb electromagnetic radiation. However, PDM~δ2, or: PDM~1.487×10−9Pe, where Peis the power output of a single electron.

关键词： Milky Way Dark Matter Halo (1049)