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Immune challenge of mating effort:steroid hormone profile,dark ventral patch and parasite burden in relation to intrasexual competition in male Iberian red deer

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Integrative Zoology 2020年第4期15卷 262-275页

作者： Eva DE la PEÑA JoséMARTÍN Isabel BARJA Raúl PÉREZ-CABAllERO Isabel ACOSTA Juan CARRANZA Wildlife Research Unit University of CórdobaCórdobaSpain Department of Evolutionary Ecology National Museum of Natural Sciences(Spanish Research CouncilCSIC)MadridSpain Department of Biology Zoology UnitAutonomous University of MadridMadridSpain Biodiversity and Global Change Research Centre Autonomous University of MadridMadridSpain Parasitology and Parasitic Diseases Unit Animal Health DepartmentUniversity of CórdobaCórdobaSpain laboratory of Malaria Immunology and Vaccinology National Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMarylandUSA

Testosterone secretion may regulate the reproductive effort and the development of sexual traits,but it may also involve costs at the immunological and metabolic ***,the evidence for this trade-off in wild populations is *** also plays an important role in mediating the reproductive and immune *** this study,we analyzed whether the endoparasite burden relates to hormonal levels(fecal testosterone and cortisol metabolites)and/or morphological sexual traits(size of the dark ventral patch,a trait that indicates reproductive effort in males)in male Iberian red *** this purpose,we sampled male red deer harvested during hunting actions in 2 types of populations in south western Spain that differed in structure,affecting the level of male–male competition for *** used coprological analyses to estimate the parasite burden mainly of gastrointestinal and bronchopulmonary nematodes and of protozoa,and assessed testosterone and cortisol metabolite levels from fecal *** found a positive relationship of host parasitation with both testosterone levels and the size of the dark ventral patch,but these relationships depended on the intensity of male–male competition in the population,being only found under the high-competition *** results are discussed under the hypothesis of the testosterone immunocompetence handicap,suggesting a cost at the immunological level,and,therefore,higher susceptibility to parasite infection in males that make a greater reproductive ***,this effect seems to be modulated by the social environment(male–male competition)that might lead to different optima in testosterone production and sexual trait development.

关键词： dark ventral patch fecal testosterone metabolites intrasexual competition male Iberian red deer parasite burden

Digit Sets for Self-similar Tiles

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Acta Mathematicae Applicatae Sinica 2015年第2期31卷 493-498页

作者： Yu-Mei XUE la-na lI School of Mathematics and System Sciences and lMIB Beihang University

A new class of digit sets, which we called very weak product-form digit sets, is introduced and it is shown that they are tile digit set for self-similar tiles. This extends previous results about product-form and wea... 详细信息

关键词： self-similar tile product-form digit set weak product-form digit set very weak product-form digit set

Correlating the electronic structure of perovskite la_(1-x)SrxCoO_(3) with activity for the oxygen evolution reaction:The critical role of Co 3d hole state

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Journal of Energy Chemistry 2022年第2期31卷 637-645页

作者： Zechao Shen Mei Qu Jueli Shi Freddy E.Oropeza Victor A.de la Peña O’Shea Giulio Gorni C.M.Tian Jan P.hofmann Jun Cheng Jun li Kelvin h.l.Zhang State Key laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina Photoactivated Processes Unit IMDEA Energy InstituteParque Tecnológico de MóstolesAvda.Ramón de la Sagra 328935 MóstolesMadridSpain CEllS-AlBA Synchrotron Carrer de la Llum 2-2608290 Cerdanyola del VallèsSpain Surface Science laboratory Department of Materials and Earth SciencesTechnical University of Darmstadt Otto-Berndt-Strasse 364287 DarmstadtGermany

Perovskite laCoO_(3) is being increasingly explored as an effective low-cost electrocatalyst for the oxygen evolution reaction(OER).Sr doping in laCoO_(3)(la1-xSrxCoO_(3))has been found to substantially increase its catalytic *** this work,we report a detailed study on the evolution of the electronic structure of la1-xSrxCoO_(3) with 0≤x≤1 and its correlation with electrocatalytic activity for the OER.A combination of X-ray photoemission spectroscopy(XPS)and X-ray absorption spectroscopy(XAS)was used to unravel the electronic density of states(DOS)near the Fermi level(EF),which provide insights into the key electronic structure features for the enhanced OER catalytic *** analysis on the Co l-edge XAS suggest that laCoO_(3) has a low spin state with t_(2g)^(6) e_(g)^(0) configuration at room *** implies that the high OER catalytic activity of laCoO_(3) should not be rationalized by the occupancy of eg=1 *** Sr^(2+) for la^(3+) in laCoO_(3) induces Co4+oxidation states and effectively dopes hole states into the top of valence band.A semiconductor-to-metal transition is observed for x>0.2,due to the holeinduced electronic DOS at the EF and increased hybridization between Co 3 d and O 2 *** an electronic modulation enhances the surface adsorption of the*Oh intermediate and reduces the energy barrier for interfacial charge transfer,thus improving the OER catalytic activity in la_(1-x)Sr_(x)CoO_(3).In addition,we found that the la_(1-x)Sr_(x)CoO_(3) surface undergoes amorphization after certain period of OER measurement,leading to a partial deactivation of the *** Sr doping levels accelerated the amorphization process.

关键词： Perovskite oxide Oxygen evolution Cobalt Electronic structure

Truly optimal semi-active damping to control free vibration of a single degree of freedom system

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Theoretical & Applied Mechanics letters 2024年第2期14卷 142-145页

作者： Viet Duc la Ngoc Tuan Nguyen Institute of Mechanics Vietnam Academy of Science and TechnologyHanoi 10000Vietnam Graduate University of Science and Technology Vietnam Academy of Science and TechnologyHanoi 10000Vietnam

This paper studies a single degree of freedom system under free vibration and controlled by a general semiactive damping.A general integral of squared error is considered as the performance index.A one-time switching damping controller is proposed and *** pontryagin maximum principle is used to prove that no other form of semi-active damping can provide the better performance than the proposed one-time switching damping.

关键词： Analytical optimization Quadratic integral lyapunov equation Pontryagin maximum principle

Cosmology with Two Compactification Scales

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Chinese Physics letters 2000年第4期17卷 310-312页

作者： A.G.Agnese M.la Camera Dipartimento di Fisica delPUniversita di Genova Istituto Nazionale di Fisica NucleareSezione di Genova Via Dodecaneso 3316146 GenovaItaly

We consider a(4+d)-dimensional spacetime broken up into a(4-n)-dimensional Minkowski spacetime(where n goes from 1 to 3)and a compact(n+d)-dimensional *** the present time the n compactification radii are of the order... 详细信息

关键词： manifold. length. Minkowski

All-Ti3C2TA:MXene Based Flexible On-chip Microsupercapacitor Array

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Chemical Research in Chinese Universities 2020年第4期36卷 694-698页

作者： lI la ChEN Di ShEN Guozhen State Key laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of Sciences&Center of Materials Science and Optoelectronic EngineeringUniversity of Chinese Academy of SciencesBeijing 100083P.R.China School of Mathematics and Physics University of Science and Technology'BeijingBeijing 100083P.R.China

Flexible on-chip microsupercapacitors(MSCs)are highly desired for integrated wearable or portable elec-tromics due to their advantages of small size,high power density,easy integration,long lifespan,high security,and *** output voltage of MSCs can be improved by designing MSC arrays,which could further expand their application *** this work,we proposed a facile laser direct cutting method to prepare an on-chip flexible MSC array using TiC,T,MXene as both current collector and electrode *** designed MSC in PVAh2SO4 all-solid-state gel electrolvte exhibits a large volume/areal capacitance of 770.72 F/cm^3(46.24 mF/cm^2)at a scan rate of 20 mV/s,a high energy density of 68.51 mWh/cm^3 at a power density of 6.16 W/cm^3,excellent cveling stability with capacitance retention of 98.50%after 10000 charge/discharge *** MSC also shows superior flexibility and stabilitv even after repetition of charge/discharge cvcles under the convex and concave bending *** *** assembled MSC array(4 in series)provides a high voltage of 3.2 V,which could easily power a purple light-emitting diode more than 10 min,demonstrating its potential application in integrated portable/wearable devices.

关键词： Ti3C2Tx MXene Microsupercapacitor laser cutting Flexible energy storage

Two upper bounds for the Erdos-hooley Delta-function

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Science China Mathematics 2023年第12期66卷 2683-2692页

作者： Regis de la Breteche Gerald Tenenbaum Institut de Mathematiques Universite Paris CiteSorbonne UniversiteCNRSParis F-75013France Institut Elie Cartan Universite de LorraineVandoeuvre-les-NancyBP 70239France

For integer n≥1 and real u,let Δ(n,u):=|{d:d] n,e^(u)he Erdos-hooley Deltafunction is then defined by Δ(n):=Max_(u∈R)Δ(n,u).We improve the current upper bounds for the average and normal orders of ... 详细信息

关键词： concentration of divisors average order normal order Waring’s problem

Concentrations and sources of an emerging pollutant, decabromodiphenylethane (DBDPE), in sewage sludge for land application

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Journal of Environmental Sciences 2012年第3期24卷 558-563页

作者： De la Torre A Concejero M A Martínez M A Persistent Organic Pollutant Group Environment Department CIEMAT Avd. Complutense 22 Madrid 28040 Spain

The presence of an emerging brominated flame retardant, decabromodiphenylethane （DBDPE）, has been confirmed in Spanish sewage sludge. Thirty one samples from different urban wastewater treatment plants （WWTPs） were analyzed for this brominated flame retardant. DBDPE was positively identified and quantified in all samples at lower concentrations （47.0 ± 29.7 ng/g dry weight （dw）; mean ± SD） than those obtained for decabromodiphenyl ether （BDE-209）（290 ± 236 ng/g dw; mean ± SD） in a previous study. Influence of the WWTP characteristics in the pollutant levels was evaluated. No significant correlations were obtained between DBDPE concentrations and the population or sewage sludge production rate associated with the plants, neither wastewater treatment method. Sources of DBDPE in the sludge were also evaluated. Data indicate a common origin for DBDPE and BDE-209, which may be related to leaching processes during the use and disposal of consumer products containing these chemicals. Nevertheless, DBDPE contents are not influenced by industrial activities, which suggests that the infusion of DBDPE commercial mixture is not a source of this chemical into the environment, and indicates that the use of DBDPE in the Spanish industry is still low compared to deca-BDE.

关键词： decabromodiphenylethane polybrominated diphenyl ethers wastewater treatment plants sewage sludge

Frictional Behavior of a Micro-sized Superconducting Fiber in a low-Temperature Medium： Experimental and Computational Analysis

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Acta Mechanica Solida Sinica 2018年第4期31卷 405-415页

作者： Shiren la Jun Wang Xingyi Zhang Youhe Zhou Department of Mechanics and Engineering Sciences College of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China Key laboratory of Mechanics on Disaster and Environment in Western China Attached to the Ministry of Education of China Lanzhou University Lanzhou 730000 China

The purpose of the current study is to explore the frictional behavior of a micro- sized superconducting fiber at the low-temperature condition. At first, a highly precise tribometer composed of a superconducting fiber wrapping around a cylinder made of pure Cu was immersed in liquid nitrogen. The force and displacement resolutions of the experimental system were as high as 0.01 mN and 0.03 ~m, respectively. The NbTi fibers with diameters ranging from 22.9 to 115 ~m were used in the experiments, and their frictional behaviors in three media, i.e., liquid nitrogen, air and water, were systemically investigated. It was found that the frictional force in air showed a remarka.le size effect. The existence of water medium could significantly reduce the frictional force, but could not eliminate the size effect. For the samples with the same diameter, the frictional force in liquid nitrogen was about 1.4 times of that in air, accompanied with remark- able stick-slip phenomenon. Notably, the fiber＇s frictional behavior in liquid nitrogen showed no dependence on diameter. In order to interpret these phenomena, the frictional behaviors of the fibers in air, water and liquid nitrogen were simulated using a modified spring-slider model, by taking into account the influence of hydrophilicity on surface roughness, and the influence of surface roughness on the fiber＇s frictional behavior. The simulation results were consistent with the experimental data qualitatively.

关键词： Micro-sized superconducting fiber Frictional behavior Surface roughness hydrophilic-ity Stick-slip Size effect Modified spring-slider model