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Neuroscience Bulletin 2012年第5期28卷 517-531页

作者： S.espíndola A Vilches-Flores e.hernández-echeagaray Unidad de Biomedicina FES-I Universidad Nacional Autónoma de México Los Reyes IztacalaC. P. 54090 TlalnepantlaMéxico

Objective The aim of the present study was to determine the changes in the mRNA levels of neurotrophins and their receptors in the striatal tissue of mice treated with 3-nitropropionic acid （3-NP）. Methods At 1 and 48 h after the last drug administration, the mRNA expression of nerve growth factor, brain-derived neurotrophic factor, neurotrophin-3 and neurotrophin-4/5 as well as their receptors p75, TrkA, TrkB and TrkC, was evaluated using semi-quantitative （semi- Q） and real-time RT-PCR. β-actin mRNA and ribosomal 18S （18S rRNA） were tested as internal controls. Results 3-NP treatment did not affect mRNA expression of all neurotrophins and their respective receptors equally. Also, differences in neurotrophin and receptor mRNA expression were observed between semi-Q and real-time RT-PCR. Real-time RT-PCR was more accurate in evaluating the mRNA expression of the neurotrophins than semi-Q, and 18S rRNA was more reliable than β-actin as an internal control. Conclusion Neurotrophins and their receptors expression is differentially affected by neuronal damage produced by inhibition of mitochondrial respiration with 3-NP treatment in low, sub-chronic doses in vivo.

关键词： neurotrophins striatum neurodegenerative disease PCR 18S 3-nitropropionic acid

Attaching CF3 groups to organic molecules using trifluoroacetates via ion-shielding photoelectrocatalysis

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Science China Chemistry 2024年第11期67卷 3495-3497页

作者： Paula Visiedo-Jiménez Francisco Juliá-hernández Departamento de Química Inorgánica Facultad de Química Universidad de MurciaCampus de Espinardo

Fluorinated molecules play a protagonist role in pharmaceuticals, agrochemicals, and materials. The incorporation of fluoroalkyl groups into organic compounds provides them with unique chemical properties that are key...

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Litterfall production modeling based on climatic variables and nutrient return from stands of eucalyptus grandis Hill ex Maiden and Pinus taeda L.

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Journal of Forestry Research 2024年第5期35卷 26-36页

作者： Andrés Baietto Andrés Hirigoyen Jorge.hernández Amabelia del Pino Forest Department Faculty of AgronomyUniversity of the Republic12900 MontevideoUruguay National Research Program of Forest Production National Agriculture Research InstituteINIA97000 TacuarembóUruguay Soil and Water Department Faculty of AgronomyUniversity of the Republic12900 MontevideoUruguay

Native grasslands in the Pampas of South America are increasingly being replaced by eucalyptus and Pinus *** short rotation regimes used for the stands require high nutrient levels,with litterfall being a major source of nutrient *** model the litterfall production using climatic variables and assess the nutrient return in 14-year-old eucalyptus grandis and Pinus taeda stands,we measured litter production over 2 years,using conical litter traps,and monitored climatic *** temperature,accumulated precipitation,and mean maximum vapor pres-sure deficit at the seasonal level influenced litterfall produc-tion by ***;seasonal accumulated precipitation and mean maximum temperature affected litterfall by *** regression tree modeling based on these climatic vari-ables had great accuracy and predictive power for ***(N=33;MAe(mean absolute error)=0.65;RMSe(root mean square error)=0.91;R^(2)=0.71)and ***(N=108;MAe=1.50;RMSe=1.59;R^(2)=0.72).The nutrient return followed a similar pattern to litterfall deposition,as well as the order of importance of macronutrients(***:Ca>N>K>Mg>P;***:N>Ca>K>Mg>P)and micronutrients(*** and ***:Mn>Fe>Zn>Cu)in both *** study constitutes a first approximation of factors that affect litterfall and nutrient return in these systems.

关键词： Afforestation Litterfall Nutrient recycling Climate modeling Myrtaceae Pinaceae

The dark side of cyclooctatetraene(COT):Photophysics in the singlet states of“self-healing”dyes

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Chinese Chemical Letters 2024年第8期35卷 225-228页

作者： Supphachok Chanmungkalakul Syed Ali Abbas Abedi Federico J.hernández Jianwei Xu Xiaogang Liu Fluorescence Research Group Singapore University of Technology and DesignSingapore 487372Singapore Department of Chemistry University College LondonLondon WC1H 0AJUnited Kingdom Institute of Sustainability for Chemicals Energy and Environment(ISCE2)Agency for ScienceTechnology and Research(A^(∗)STAR)Jurong Island 627833Singapore

Cyclooctatetraene(COT)attachment to fluorophores(“self-healing”dyes)is known for quenching reac-tive triplet states via triplet-state energy transfer(TeT),enhancing ***,COT’s impact on singlet states remains *** calculations reveal that COT induces energy transfer to dark states in deep blue dyes while promoting photoinduced electron transfer(PeT)and intersystem crossing(ISC)in visible dyes,potentially compromising brightness and/or *** address this,we pro-pose the use of △e descriptor to optimize COT’s *** findings uncover COT’s multifaceted *** insights will guide the development of superior triplet state quenchers and photostable dyes.

关键词： Cyclooctatetraene Photostability Triplet state quencher energy transfer electron transfer

Using fused filament fabrication to improve the tribocorrosion behaviour of 17-4 PH SS in comparison to other metal forming techniques

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Friction 2024年第10期12卷 2325-2343页

作者： Cristina GARCÍA-CABeZÓN Juan Alfonso NARANJO Celia GARCÍA-hernÁndez Cristina BeRGeS Gemma HeRRANZ Fernando MARTÍN-PeDROSA Materials engineering E.I.I.Universidad de ValladolidValladolid 47011Spain INeI-escuela Técnica Superior de Ingeniería Industrial(eTSII) Universidad de Castilla La ManchaCastilla-La Mancha 13071Spain

Fused filament fabrication(FFF)is one of the additive manufacturing processes which has gained more interest because of its simplicity and *** technology is similar to the conventional metal injection moulding(MIM)process,consisting of the feedstock preparation of metal powder and polymer binders,followed by layer-by-layer 3D printing(FFF)or injection(MIM)to create green parts and,finally,debinding and ***,both technologies provide near-dense *** work presents an in-depth study of the processing method’s *** porosity,microstructure,hardness,corrosion,and tribocorrosion behaviour are compared for 17-4 PH SS samples processed from powder by additive manufacturing using FFF and MIM,as well as conventional powder metallurgy(PM)*** samples exhibited the highest macro and microhardness,while corrosion behaviour was similar for both MIM and FFF samples,but superior in comparison to conventional PM ***,the FFF-as fabricated samples displayed a significant improvement in tribocorrosion resistance that could be explained by the higher proportion of delta ferrite and retained austenite in their microstructure.

关键词： 17-4 PH SS fused filament fabrication(FFF) metal injection moulding(MIM) corrosion behaviour powder metallurgy(PM) tribocorrosion behaviour

DNA metabarcoding reveals seasonal changes in diet composition across four arthropod-eating lizard species(Phrynosomatidae:Sceloporus)

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Integrative Zoology 2024年第3期19卷 480-495页

作者： Mauricio hernÁndez Stephanie HeReIRA-PACHeCO Antton ALBeRDI Aníbal H.DÍAZ De LA VeGA-PÉReZ Arturo eSTRADA-TORReS Sergio ANCONA Yendi e.NAVARRO-NOYA Doctorado en Ciencias Biológicas Centro Tlaxcala de Biología de la ConductaUniversidad Autónoma de TlaxcalaTlaxcalaMexico estación Científica La Malinche Centro Tlaxcala de Biología de la ConductaUniversidad Autónoma de TlaxcalaTlaxcalaMexico Center for evolutionary Hologenomics The Globe InstituteUniversity of CopenhagenCopenhagenDenmark Consejo Nacional de Ciencia y Tecnología-Centro Tlaxcala de Biología de la Conducta Universidad Autónoma de TlaxcalaTlaxcalaMexico Departamento de ecología evolutiva Instituto de EcologíaUniversidad Nacional Autónoma de MéxicoMexico CityMexico Laboratorio de Interacciones Bióticas Centro de Investigación en Ciencias BiológicasUniversidad Autónoma de TlaxcalaSan Felipe IxtacuixtlaTlaxcalaMexico

Diet composition and its ecological drivers are rarely investigated in coexisting closely related *** used a molecular approach to characterize the seasonal variation in diet composition in four spiny lizard species inhabiting a mountainous *** metabarcoding revealed that the lizards Sceloporus aeneus,***,***,and *** mostly consumed arthropods of the orders Hemiptera,Araneae,Hymenoptera,and *** terrestrial lizards *** and *** mostly predated ants and spiders,whereas the arboreal–saxicolous *** and saxicolous *** largely consumed grasshoppers and *** taxonomic and phylogenetic diversity of the prey was higher during the dry season than the rainy season,likely because reduced prey availability in the dry season forced lizards to diversify their diets to meet their nutritional *** and phylogenetic composition varied seasonally depending on the species,but only dietary composition varied with *** dietary turnover was greater in *** than in ***,suggesting site-specific seasonal variability in prey availability;no other differences among species were ***,which lives at the highest altitude in our study site,displayed interseasonal variation in diet *** differences were correlated with the species’feeding strategies and elevational distribution,which likely contributed to the coexistence of these lizard species in the studied geographic area and beyond.

关键词： arthropod-eating lizards diet breadth environmental barcoding mountainous ecosystem seasonal dietary shifts

BaTiO3 solid solutions co-doped with Gd3+ and eu3+:Synthesis,structural evolution and dielectric properties

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Journal of Rare earths 2024年第10期42卷 1920-1926页

作者： R.Martínez-López M.Pérez-Labra J.A.Romero-Serrano F.R.Barrientos-hernández M.Reyes-Pérez M.I.Valenzuela-Carrillo G.Urbano-Reyes V.e.Reyes-Cruz G.I.Dávila-Pulido Academic Area of earth Sciences and Materials Autonomous University of Hidalgo State Metallurgy and Materials Department ESIQIE-IPNUPALM Autonomous University of Coahuila Boulevard Adolfo López Mateos S/n

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO3solid solutions codoped with rare earth elements(Gd3+and eu3+) prepared using the solid-state reaction method are *** pure precursor powders of BaCl3,TiO2,Gd2O3,and eu2O3were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 MPa and sintered at 1300℃ in air atmosphere for 6 h to obtain Ba1-3xGd2xTi1-3xeu4xO3（x=0,0.0015,0.01 and0.1）.X-ray diffraction（XRD） and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO3for the samples with x=0,0.0015 and 0.01, as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd3+and eu3+in the BaTiO3structure is reached for the sample with x>0.01,and the orthorhombic eu2TiO5and monoclinic BaTi2O5secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO3around 716 cm-1（LO of A1 symmetry）,515 cm-1（TO of A1 symmetry）,and 305 cm-1（B1）.The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃ with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and eu homogeneously distributed in the *** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO3 Doping europium Gadolinium Rare earths Synthesis

Role of hyperfine mixing in b→c semileptonic decays of doubly-heavy baryons

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Chinese Physics C 2010年第9期34卷 1488-1490页

作者： C.Albertus e.hernández J.Nieves Departamento de Física Fundamental e IUFFyM Universidad de Salamanca Instituto de Física Corpuscular (IFIC) Centro Mixto CSIC-Universidad de ValenciaInstitutos de Investigación de Paterna

We analyze the effects of hyperfine mixing in b → c semileptonic decays of doubly heavy *** qualitatively confirm the results by *** and *** in ***.A,2009,24： 2401– 2413,finding that mixing has a great impact on those ***,predictions without mixing differ by a factor of 2 and this discrepancy translates to the mixed case where large differences in decay widths are observed between the two calculations.

关键词： doubly-heavy baryons semileptonic decay hyperfine mixing

Semileptonic bc to cc and bb to bc baryon decays and heavy quark spin symmetry

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Chinese Physics C 2010年第9期34卷 1364-1367页

作者： J.Nieves J.M.Flynn e.hernández Instituto de Física corpuscular (IFIC) Centro Mixto Universidad de Valencia-CSICInstitutos de Investigación de Paterna School of Physics and Astronomy University of Southampton Departamento de Física Fundamental e IUFFyM Universidad de Salamanca

We study the semileptonic decays of the lowest-lying bc baryons to the lowest-lying cc baryons （Ξ （＊） bc → Ξ （＊） cc and Ω （＊） bc → Ω （＊） cc ）,in the limit m b,m c Λ QCD and close to the zero recoil *** separate heavy quark spin symmetries make it possible to describe all these decays using a single form *** also show how these constraints can be used to test the validity of different quark model *** to bc baryon decays are also discussed.

关键词： heavy quark spin symmetry semileptonic decays constituent quark modelsIf

Annual variation of adult survival of a south-temperate House Wren population in Argentina

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Avian Research 2024年第2期15卷 229-237页

作者： Gustavo J.Fernandez Mariana e.Carro Paulo e.Llambías Grupo de Investigacion en ecofisiología de Fauna Silvestre INIBIOMA-CONICETAsentamiento Universitario San Martín de los Andes(AUSMA)Universidad Nacional Del ComahuePasaje de la Paz 235(8370)San Martín de los AndesNeuquenArgentina Grupo de Investigacion de Biología de Aves IADIZA CCT-MendozaUniversidad Nacional de CuyoAvenida RuizLeal s/n Parque General San Martin5500MendozaArgentina

Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population *** numerous studies on this subject in north-temperate environments,there is a lack of equivalent studies at similar latitudes in the ***,we used a 14-year dataset of capture,banding,and resighting to estimate the annual variation in the apparent adult survival probability of a south-temperate population of House Wrens(Troglodytes aedon bonariae).We evaluated temporal variation in sur-vival and the effect of environmental(climatic)and demographic variables(adult abundance,total number of fledglings produced during each breeding season)on survival *** found that the probability of adult survival decreased as the abundance of breeding adults *** density-dependent effect could be related to the resident lifestyle of southern House Wrens,which could determine an intense competition for territories and resources that ultimately would affect their survival.

关键词： Annual variation CJS Density-dependence Survival Troglodytes aedon bonariae