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Juvenile survival curves in a solitary ground squirrel with a prolonged hibernation:effects of individual characteristics,environment,and maternal investment

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Current Zoology 2024年第1期70卷 13-23页

作者： Nina A.vasilieva Liudmila e Savinetskaya Andrey v.Tchabovsky A.N.Severtsov Institute of ecology and evolution Russian Academy of SciencesMoscow 119071Russia

Juvenile survival is a key life-history influence on population dynamics and adaptive evolution.We analyzed the effects of individual chara-cteristics,early environment,and maternal investment on juvenile survival in a large solitary hibernating rodent-yellow ground squirrel Spermophilus fulvus using Cox mixed-effects models.Only 48%of weaned pups survived to dispersal and 17%survived to hibernation.early life expectancy was primarily determined by individual characteristics and,to a lesser extent,by the early environment.The strongest and pos-itive predictor of juvenile survival was body mass which crucially affected mortality immediately after weaning.Males suffered higher mortality than females after the onset of dispersal;however,the overall difference between sexes was partly masked by high rates of mortality in the first days after emergence in both sexes.Later emerged juveniles had lower life expectancy than the earliest pups.The overall effect of local juvenile density was positive.Prolonged lactation did not enhance juvenile survival:Pups nursed longer survived shorter than the young nursed for a shorter period.Our findings support the hypothesis that females of S.fulvus cannot effectively regulate maternal expenditures to mitigate the effects of unfavorable conditions on their offspring.The strategy to deal with seasonal time constraints on life history in female S.fulvus suggests an early termination of maternal care at the cost of juvenile quality and survival.This female reproductive strategy corresponds to a"fast-solitary"life of folivorous desert-dwelling S.fulvus and other solitary ground squirrels with prolonged hibernation.

关键词： early-life conditions ground squirrels hibernation juvenile mortality maternal investment survival curves

emission colour tuning in KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)phosphor

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Journal of Rare earths 2024年第1期42卷 57-65,I0002页

作者： Janani K Gayathri e vijayatha v Ramasubramanian S Thiyagarajan P Department of Science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of Sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of Physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction technique.For each of the Yb^(3+)/er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and dopants.Upconversion luminescence emissions of green and red colour were detected for the synthesized phosphors.The changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared phosphors.In the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green emission.The rare-earth er/Ho doped KYbF4shows strong red emission compared to other hosts.KYF_(4):Yb,er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,er-doped KGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 mW.Downshifting photoluminescence studies and decay curve analysis were carried out using Uv light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)sample.This study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths energy transfer upconversion Downshifting Colour coordinates

The multi-impurity system in CdSe nanoplatelets:electronic structure and thermodynamic properties

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Communications in Theoretical Physics 2024年第3期76卷 165-173页

作者： D A Baghdasaryan v A Harutynyan e M Kazaryan H A Sarkisyan Russian-Armenian University H Emin 1230051YerevanArmenia Institute of Applied Problems of Physics 25 Nersisyan St0014YerevanArmenia

This paper theoretically studies the impurity states and the effects of impurity concentration and configuration on the optical,electrical,and statistical properties of CdSe nanoplatelets(NPLs).An image charge-based model of electron-impurity interaction is proposed.The charge-carrier energy spectra and corresponding wave functions depending on the impurity number and configuration are calculated.The electron binding energies are calculated for different NPL thicknesses.It is shown that the image charge-based interaction potential that arises due to the dielectric constants mismatch is much stronger than the interaction potential that does not take such a mismatch into account.Also,it is demonstrated that the binding energies are increasing with the number of impurities.We calculate the canonical partition function using the energy levels of the electron,which in turn is used to obtain the mean energy,heat capacity,and entropy of the non-interacting electron gas.The thermodynamic properties of the non-interacting electron gas that depend on the geometric parameters of the NPL,impurity number,configuration,and temperature are studied.

关键词： nanoplateletes thermodynamic properties impurity states

Nanomotion of bacteria to determine metabolic profile

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Nanotechnology and Precision engineering 2024年第1期7卷 1-9页

作者： S.N.Pleskova e.v.Lazarenko N.A.Bezrukov R.N.Kriukov A.v.Boryakov M.e.Dokukin S.I.Surodin Research Laboratory of Scanning Probe Microscopy Lobachevsky State University of Nizhny NovgorodNizhny Novgorod 603950Russia Department of Nanotechnology and Biotechnology Nizhny Novgorod State Technical University n.a.R.E.AlekseevNizhny Novgorod 603950Russia Sarov Physics and Technology Institute National Research Nuclear University MEPhISarov 607186Russia

In addition to their visible motion such as swimming(e.g.,with the help ofﬂagella),bacteria can also exhibit nanomotion that is detectable only with highly sensitive instruments,and this study shows that it is possible to detect bacterial nanomotion using an AFM detection system.The results show that the nanomotion characteristics depend on the bacterial strain,and that nanomotion can be used to sense the metabolic activity of bacteria because the oscillations are sensitive to the food preferences of the bacteria and the type of surrounding medium.

关键词： Nanomotion Bacteria Cantilever Oscillation Atomic force microscopy Metabolism

Long-Term Trends of Carbon Monoxide Total Columnar Amount in Urban Areas and Background Regions:Ground-and Satellite-based Spectroscopic Measurements

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Advances in Atmospheric Sciences 2018年第7期35卷 785-795页

作者： Pucai WANG N.F.eLANSKY Yu.M.TIMOFeev Gengchen WANG G.S.GOLITSYN M.v.MAKAROvA v.S.RAKITIN Yu.SHTABKIN A.I.SKOROKHOD e.I.GReCHKO e.v.fokeeva A.N.SAFRONOv Liang RAN Ting WANG LAGeO Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China A.M.Obukhov Institute of Atmospheric Physics Russian Academy of SciencesMoscow 119017Russia St.Petersburg State University Saint-Petersburg 198904Russia

A comparative study was carried out to explore carbon monoxide total columnar amount（CO TC） in background and polluted atmosphere, including the stations of ZSS（Zvenigorod）, ZOTTO（Central Siberia）, Peterhof, Beijing, and Moscow,during 1998–2014, on the basis of ground-and satellite-based spectroscopic measurements. Interannual variations of CO TC in different regions of eurasia were obtained from ground-based spectroscopic observations, combined with satellite data from the sensors MOPITT（2001–14）, AIRS（2003–14）, and IASI Met Op-A（2010–13）. A decreasing trend in CO TC（1998–2014） was found at the urban site of Beijing, where CO TC decreased by 1.14% ± 0.87% yr^（-1）. Meanwhile, at the Moscow site, CO TC decreased remarkably by 3.73% ± 0.39% yr^（-1）. In the background regions（ZSS, ZOTTO, Peterhof）, the reduction was 0.9%–1.7% yr^（-1） during the same period. Based on the AIRSv6 satellite data for the period 2003–14, a slight decrease（0.4%–0.6% yr^（-1）） of CO TC was detected over the midlatitudes of eurasia, while a reduction of 0.9%–1.2% yr^（-1） was found in Southeast Asia. The degree of correlation between the CO TC derived from satellite products（MOPITTv6 Joint, AIRSv6 and IASI Met Op-A） and ground-based measurements was calculated, revealing significant correlation in unpolluted regions.While in polluted areas, IASI Met Op-A and AIRSv6 data underestimated CO TC by a factor of 1.5–2.8. On average, the correlation coefficient between ground-and satellite-based data increased significantly for cases with PBL heights greater than 500 m.

关键词： carbon monoxide trend spectroscopic measurement MOPITT AIRS IASI

Simple collective model for nuclear chiral mode

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Frontiers of physics 2024年第2期19卷 1-5页

作者： R.v.Jolos e.A.Kolganova D.R.Khamitova Joint Institute for Nuclear Research 141980 DubnaMoscow regionRussia Dubna State University 141982 DubnaMoscow RegionRussia

A simple semi-analytical collective model that takes into account the limitations of the variation interval of the collective variable is suggested to describe the chiral dynamics in triaxial odd−odd nuclei with a fixed particle−hole configuration.The collective Hamiltonian is constructed with the potential energy obtained using the postulated ansatz for the wave function symmetric with respect to chiral transformation.By diagonalizing the collective Hamiltonian the wave functions of the lowest states are obtained and the evolution of the energy splitting of the chiral doublets in transition from chiral vibration to chiral rotation regime is demonstrated.

关键词： collective model nuclear chiral

Supplementation of vitamin e or a botanical extract as antioxidants to improve growth performance and health of growing pigs housed under thermoneutral or heat-stressed conditions

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1101-1118页

作者： Ysenia v.Silva‑Guillen Consuelo Arellano Jeffrey Wiegert R.Dean Boyd Gabriela e.Martinez eric van Heugten Department of Animal Science North Carolina State UniversityRaleighNC 27695USA Department of Statistics North Carolina State UniversityRaleighNC 27695USA Department of Animal Science Texas A&M UniversityCollege StationTX 77843USA Animal Nutrition Research LLCAlvatonKY 42122USA.

Background Heat stress has severe negative consequences on performance and health of pigs,leading to significant economic losses.The objective of this study was to investigate the effects of supplemental vitamin e and a botanical extract in feed or drinking water on growth performance,intestinal health,and oxidative and immune status in grow-ing pigs housed under heat stress conditions.Methods Duplicate experiments were conducted,each using 64 crossbred pigs with an initial body weight of 50.7±3.8 and 43.9±3.6 kg and age of 13-week and 12-week,respectively.Pigs(n=128)were housed individually and assigned within weight blocks and sex to a 2×4 factorial arrangement consisting of 2 environments(thermo-neutral(21.2℃)or heat-stressed(30.9℃))and 4 supplementation treatments(control diet;control+100 IU/L of D-α-tocopherol in water;control+200 IU/kg of DL-α-tocopheryl-acetate in feed;or control+400 mg/kg of a botanical extract in feed).Results Heat stress for 28 d reduced(P≤0.001)final body weight,average daily gain,and average daily feed intake(-7.4 kg,-26.7%,and-25.4%,respectively)but no effects of supplementation were detected(P>0.05).Serum vitamin e increased(Pvitamin e supplementation in water and in feed(1.64 vs.3.59 and 1.64 vs.3.24),but not for the botanical extract(1.64 vs.1.67 mg/kg)and was greater when supplemented in water vs.feed(P=0.002).Liver vitamin e increased(Pvitamin e supplementations in water(3.9 vs.31.8)and feed(3.9 vs.18.0),but not with the botanical extract(3.9 vs.4.9 mg/kg).Serum malondialdehyde was reduced with heat stress on d 2,but increased on d 28(interaction,Peater(Pementation compared to control.Cellular proliferation was reduced(P=0.037)in the jejunum under heat stress,but increased in the ileum when vitamin e was supplemented in feed and water under heat stress(interaction,P=0.04).Tumor necrosis factor-αin jejunum and ileum mucosa decreased by heat stress(Peduced by vitamin e sup-plementations under heat

关键词： Botanical extract Growing pigs Heat stress Immune status Oxidative status Tocopherol Water

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Antibacterial HA-coatings on bioresorbable Mg alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1965-1985页

作者： K.v.Nadaraia D.v.Mashtalyar M.A.Piatkova A.I.Pleshkova I.M.Imshinetskiy M.S.Gerasimenko e.A.Belov v.v.Kumeiko D.N.Kozyrev K.A.Fomenko v.v.Mostovaya B.R.Torpanov A.R.Biktimirov I.S.Osmushko S.L.Sinebryukhov S.v.Gnedenkov Institute of Chemistry FeB RAS Far eastern Federal University A.v.Zhirmunsky National Scientific Center of Marine Biology FeB RAS Regional Clinical Dermatovenerological Dispensary NMIC “Treatment and Rehabilitation Center”

In this study, a calcium-phosphate coating was formed on a Mg-Mn-Ce alloy by the plasma electrolytic oxidation(PeO). The antibiotic vancomycin, widely used in the treatment of infections caused by Staphylococcus aureus(S. aureus), was impregnated into the coating.Samples with vancomycin showed high bactericidal activity against S. aureus. The mechanical and electrochemical properties of the formed coatings were studied, as well as in vitro cytotoxicity tests and in vivo tests on mature male rats were performed. According to SeM,eDS, XRD and XPS data, coatings had a developed morphology and contained hydroxyapatite, which indicates high biocompatibility.The analysis of roughness of coatings without and with vancomycin did not reveal any differences, confirming the high roughness of the samples. During electrochemical tests, an increase in corrosion resistance by more than two times after the application of PeO coatings was revealed. According to the results of an in vivo study, after 28 days of the implantation of samples with calcium phosphate PeO coating and vancomycin, no signs of inflammation were observed, while an inflammatory reaction developed in the area of implantation of bare alloy,followed by encapsulation. Antibiotic release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day 28. Throughout the experiment, no significant deviations in the condition and behavior of the animals were observed; clinical tests did not reveal a systemic toxic reaction.

关键词： Bioactive coatings Biocompatibility Mg alloy Plasma electrolytic oxidation Hydroxyapatite vancomycin

MicroRNAs as potential biomarkers for diagnosis of schizophrenia and influence of antipsychotic treatment

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Neural Regeneration Research 2024年第7期19卷 1523-1531页

作者： Bridget Martinez Philip v.Peplow Department of Pharmacology University of Nevada-RenoRenoNVUSA Department of Medicine University of Nevada-RenoRenoNVUSA Department of Anatomy University of OtagoDunedinNew Zealand

Chara cterized by positive symptoms(such as changes in behavior or thoughts,including delusions and hallu cinations),negative symptoms(such as apathy,anhedonia,and social withdrawal),and cognitive impairments,schizophrenia is a chro nic,severe,and disabling mental disorder with late adolescence or early adulthood onset,Antipsychotics are the most commonly used drugs to treat schizophrenia,but those currently in use do not fully reverse all three types of symptoms characte rizing this condition.Schizophrenia is frequently misdiagnosed,resulting in a delay of or inappropriate treatment.Abnormal expression of microRNAs is connected to brain development and disease and could provide novel biomarkers for the diagnosis and prognosis of schizophrenia.The recent studies reviewed included microRNA profiling in blood-and urine-based materials and nervous tissue mate rials.From the studies that had validated the preliminary findings,potential candidate biomarkers for schizophrenia in adults could be miR-22-3p,-30e-5p,-92a-3p,-148b-5p,-181a-3p,-181a-5p,-181b-5p,-199 b-5p,-137 in whole blood,and miR-130b,-193a-3p in blood plasma.Antipsychotic treatment of schizophrenia patients was found to modulate the expression of certain microRNAs including miR-130b,-193a-3p,-132,-195,-30e,-432 in blood plasma.Further studies are warranted with adolescents and young adults having schizophrenia and consideration should be given to using animal models of the disorder to investigate the effect of suppressing or overexpressing specific microRNAs.

关键词： antipsychotics biomarkers blood exosomes blood plasma brain tissue exosomes brain tissues leukocytes microRNAs neural stem cells olfactory neuroepithelium schizophrenia whole blood