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First-principles calculations to investigate structural,electronic,magnetic,optical and thermodynamic properties of RE_(2)Rh_(3)Ge(RE=Pr,Sm)

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Journal of Rare Earths 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier R.Masrour M.Hamedoun J.Kharbach A.Rezzouk A.Hourmatallah n.Benzakour K.Bouslykhane Laboratory of Solid Physics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equipe de Physique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In this paper,we analyzed the physical characteristics of the ternary alloys RE_(2)Rh_(3)Ge(RE=Pr and Sm)using the first principles calculation based on functional density theory integrated in the Wien2k *** calculated formation energies of Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge are−5.3827 and−5.2782 eV/atom,respectively,showing that these alloys may exist *** results of the band structure and density of states indicate that all of the compounds tested are magnetic metals,and their magnetism is mostly related to the contribution of Pr and Sm *** total magnetic moments of Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge are 4.07245 and 11.16161μB/f.u,*** parameters such as heat capacity at constant pressure,entropy,Debye temperature,lattice volume,compressibility coefficients,and Grüneisen parameter alloys were calculated using the Gibbs algorithm and studied in depth over a large temperature range of 0-900 *** Debye temperature increases with increasing pressure and decreases with decreasing ***,the Debye temperatures calculated at p=0 GPa and T=300 K are equal to be 342 and 322 K for Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge,*** optical characteristics such as the real and imaginary portions of the dielectric function,the absorption coefficient,the energy-loss function,and the refractive index were investigated and discussed in more depth.

关键词： Magnetic metals Functional density theory Density of states Magnetic moment Optical and thermodynamic properties Rare earths

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.Sardar M.D.Hossain M.S.Sikder M.n.I.Khan M.R.Rahman Physics Discipline Khulna UniversityKhulna9208Bangladesh Department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Department ofComputer Science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh Material Science Division Atomic Energy CentreDhaka1000Bangladesh

Spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FESEM),energy dispersive X-ray(EDX),vibrating sample magnetometer(VSM),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XRD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTIR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FESEM images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EDX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EDX Resistivity

Doppler Effect: A Look from Biology Aging

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Advances in Aging Research 2024年第4期13卷 75-84页

作者： Jorge Barragán Sebastián Sánchez Department of Histology Universidad del Gran Rosario Rosario Argentina

The Doppler effect can be defined as the frequency shift suffered by a wave phenomenon, when there is a difference in relative speed between the waves generated and their source. We know that it occurs in the case of mechanical and electromagnetic waves. We propose to generalize the Doppler effect to the case of frequency changes of certain oscillatory variables in biology before and after puberty, starting from the basis that a metabolically accelerated system is equivalent to a mechanically accelerated system. We then established the following objectives: To verify if there is an average difference in heart and respiratory rates, before and after puberty. To verify the association of these frequency differences with the metabolic activity estimated as basal metabolic rate or BMR. We studied heart and respiratory rate data from healthy people of both sexes, verifying the frequency distribution before and after puberty. We also study the relationship of the frequency distribution with the evolution of the basal metabolic rate throughout life. Analysis of the results shows that the highest heart and respiratory rates occur before puberty, while the lowest rates occur after puberty. A high correlation of the evolution of the variables studied with the evolution of the metabolic acceleration of the system throughout life is also evident. Taking into account that a mechanically accelerated system is equivalent to a metabolically accelerated system, we can conclude that the frequency distribution found is the expression of a generalization of the Doppler effect in the case of biological physical systems.

关键词： Oscillatory Variables Metabolic Acceleration Mechanical Acceleration Equivalence Principle non-Inertial System Rate of Change

Accuracy of tree mapping based on hand-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests

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Journal of Forestry Research 2024年第5期35卷 14-25页

作者： Frederico Tupinambá-Simões Adrián Pascual Juan Guerra-Hernández Cristóbal Ordóñez Tiago de Conto Felipe Bravo iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIAValladolidSpain Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA Forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349‑017 LisbonPortugal

The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high *** confirm the con-sistency in the retrieval of forest structural parameters using hand-held laser scanning(HLS),before operationalizing the method,confirming the data is *** analyzed the per-formance of tree-level mapping based on HLS under differ-ent phenology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus *** area was surveyed twice during the growing season(July 2022)and once in the deciduous season(February 2022)using several scan-ning *** reference data(418 trees,15 snags)was used to calibrate the HLS data and to assess the influence of phenology when converting 3D data into tree-level attrib-utes(DBH,height and volume).The HLS-based workflow was robust at isolating tree positions and recognizing stems despite changes in ***-six percent of all pairs matched below 65 *** DBH,phenology barely altered *** observed a strong agreement when comparing HLS-based tree height *** values exceeded 2 m when comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous *** volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).HLS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed phenology conditions.

关键词： Precision forestry Forest monitoring Mobile laser scanning Forest inventory

Improving the nutritional values of yellow mealworm Tenebrio molitor(Coleoptera: Tenebrionidae) larvae as an animal feed ingredient: a review

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Journal of Animal Science and Biotechnology 2024年第1期15卷 35-52页

作者： Linggawastu Syahrulawal Magnhild Oust Torske Rumakanta Sapkota Geir næss Prabhat Khanal Animal Science Production and Welfare DivisionFaculty of Biosciences and AquacultureNord UniversitySkolegata 22Steinkjer 7713Norway Department of Environmental Science Faculty of Technical SciencesAarhus UniversityFrederiksborgvej 399Roskilde 4000Denmark

Yellow mealworm larvae(YML;Tenebrio molitor) are considered as a valuable insect species for animal feed due to their high nutritional values and ability to grow under different substrates and rearing conditions. Advances in the understanding of entomophagy and animal nutrition over the past decades have propelled research areas toward testing multiple aspects of YML to exploit them better as animal feed sources. This review aims to summarize various approaches that could be exploited to maximize the nutritional values of YML as an animal feed ingredient. In addition, YML has the potential to be used as an antimicrobial or bioactive agent to improve animal health and immune function in production animals. The dynamics of the nutritional profile of YML can be influenced by multiple factors and should be taken into account when attempting to optimize the nutrient contents of YML as an animal feed ingredient. Specifically, the use of novel land-based and aquatic feeding resources, probiotics, and the exploitation of larval gut microbiomes as novel strategies can assist to maximize the nutritional potential of YML. Selection of relevant feed supplies, optimization of ambient conditions, the introduction of novel genetic selection procedures, and implementation of effective post-harvest processing may be required in the future to commercialize mealworm production. Furthermore, the use of appropriate agricultural practices and technological improvements within the mealworm production sector should be aimed at achieving both economic and environmental sustainability. The issues highlighted in this review could pave the way for future approaches to improve the nutritional value of YML.

关键词： Alternative protein source Feed application nutritional value Yellow mealworm

Habitat and food preferences of European rabbits in core and edge populations along the invasion front PatagoniaMonte,Argentina

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Current Zoology 2024年第3期70卷 310-319页

作者： Sabrina Yasmin Bobadilla María A.Dacar Fabián M.Jaksic Ricardo A.Ojeda María Fernanda Cuevas Ecología de Mamíferos de Tierras Secas IADIZACCT-Mendoza CONICETAv.Ruiz Leal s/nParque General San MartínMendoza 5500MendozaArgentina Laboratorio de Filogeografía Taxonomía Integrativa y Ecología(LFTIE)IADIZACCT-Mendoza CONICETAv.Ruiz Leal s/nParque General San MartínMendoza 5500MendozaArgentina Center of Applied Ecology and Sustainability(CAPES) Pontifcia Universidad Católica de ChileAv.Libertador Bernardo O'Higgins 340Santiago 8320000Región MetropolitanaChile

The European rabbit Oryctolagus cuniculus is an exotic herbivorous mammal undergoing an active phase of geographical expansion in the arid ecosystems of *** Adaptive Flexibility Hypothesis states that populations at the range edge(new populations)will exhibit greater fexibility in the use of resources compared with populations located in the range core(older populations).The objective of this work was to compare the rabbit’s use of spatial and trophic resources in relation to the establishment time of their *** sampling was carried out for 2 years(2017 and 2018)in sites with different establishment times for rabbit *** sampling stratifed by type of habitat was applied using 115 fxed strip transects of 1,000 m^(2) laid out across the study *** rabbit signs were recorded in each transect,and environmental and anthropic variables were *** results show that the individuals from the range edge are more selective in the use of habitat than those from the range *** the microhabitat level,we observed a pattern in the particular components of habitat use by rabbits mainly linked to food availability and proximity to *** a trophic perspective,rabbits could show fexible adjustment to novel conditions and environments in the range *** variability in resource use by the European rabbit confrms its ecological fexibility,pivotal for their advance toward new environments in Argentina.

关键词： Arid ecosystems invasive species novel environments range invasion spatial use trophic use

Connecting cellular mechanisms and extracellular vesicle cargo in traumatic brain injury

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neural Regeneration Research 2024年第10期19卷 2119-2131页

作者： nikita Ollen-Bittle Austyn D.Roseborough Wenxuan Wang Jeng-liang D.Wu Shawn n.Whitehead Department of Anatomy and Cell Biology Western UniversityLondonONCanada Schulich School of Medicine and Dentistry Western UniversityLondonONCanada Deparment of Clinical neurological Sciences Western UniversityLondonONCanada

Traumatic brain injury is followed by a cascade of dynamic and complex events occurring at the cellular level. These events include: diffuse axonal injury, neuronal cell death, blood-brain barrier break down, glial activation and neuroinflammation, edema, ischemia, vascular injury, energy failure, and peripheral immune cell infiltration. The timing of these events post injury has been linked to injury severity and functional outcome. Extracellular vesicles are membrane bound secretory vesicles that contain markers and cargo pertaining to their cell of origin and can cross the blood-brain barrier. These qualities make extracellular vesicles intriguing candidates for a liquid biopsy into the pathophysiologic changes occurring at the cellular level post traumatic brain injury. Herein, we review the most commonly reported cargo changes in extracellular vesicles from clinical traumatic brain injury samples. We then use knowledge from animal and in vitro models to help infer what these changes may indicate regrading cellular responses post traumatic brain injury. Future research should prioritize labeling extracellular vesicles with markers for distinct cell types across a range of timepoints post traumatic brain injury.

关键词： axonal injury biomarkers blood-brain barrier chronic traumatic encephalopathy extracellular vesicles glial activation neuroinflammation traumatic brain injury

Interindividual Age-Independent Differences in Human CX43 Impact Ventricular Arrhythmic Risk

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Research 2024年第3期6卷 417-432页

作者： Laura García-Mendívil María Pérez-Zabalza Antoni Oliver-Gelabert JoséMaría Vallejo-Gil Javier Fañanás-Mastral Manuel Vázquez-Sancho Javier AndréBellido-Morales Alexánder Sebastián Vaca-núñez Carlos Ballester-Cuenca Emiliano Diez Laura Ordovás Esther Pueyo Biomedical Signal Interpretation and Computational Simulation group(BSICoS) Aragón Institute of Engineering ResearchUniversity of ZaragozaZaragoza 50018Spain BSICoS Instituto de Investigación Sanitaria Aragón(IISA)Zaragoza 50018Spain Centro Universitario de la Defensa(CUD) Zaragoza 50090Spain. Department of Cardiovascular Surgery University Hospital Miguel ServetZaragoza 50009Spain. Institute of Experimental Medicine and Biology of Cuyo(IMBECU) CONICETMendoza 5500Argentina. Fundación Agencia Aragonesa para la Investigación y el Desarrollo(ARAID) Zaragoza 50018Spain. Biomedical Research networking Center in Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)Zaragoza 50018Spain.

Connexin 43 (CX43) is one of the major components of gap junctions, the structures responsible for the intercellular communication and transmission of the electrical impulse in the left ventricle. There is limited information on the histological changes of CX43 with age and their effect on electrophysiology, especially in humans. Here, we analyzed left ventricular biopsies from living donors starting at midlife to characterize age-related CX43 remodeling. We assessed its quantity, degree of lateralization, and spatial heterogeneity together with fibrotic deposition. We observed no significant age-related remodeling of CX43. Only spatial heterogeneity increased slightly with age, and this increase was better explained by biological age than by chronological age. Importantly, we found that CX43 features varied considerably among individuals in our population with no relevant relationship to age or fibrosis content, in contrast to animal species. We used our experimental results to feed computational models of human ventricular electrophysiology and to assess the effects of interindividual differences in specific features of CX43 and fibrosis on conduction velocity, action potential duration, and arrhythmogenicity. We found that larger amounts of fibrosis were associated with the highest arrhythmic risk, with this risk being increased when fibrosis deposition was combined with a reduction in CX43 amount and/or with an increase in CX43 spatial heterogeneity. These mechanisms underlying high arrhythmic risk in some individuals were not associated with age in our study population. In conclusion, our data rule out CX43 remodeling as an age-related arrhythmic substrate in the population beyond midlife, but highlight its potential as a proarrhythmic factor at the individual level, especially when combined with increased fibrosis.

关键词： CX43 rhythm Independent

Making bridges between preclinical and clinical insights into age-related cognitive decline

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neural Regeneration Research 2025年第8期20卷 2321-2322页

作者： David VC Brito Clévio nóbrega Algarve Biomedical Center-Research Institute(ABC-RI) Campus GambelasFaroPortugal Algarve Biomedical Center-(ABC) Campus GambelasFaroPortugal Faculty of Medicine and Biomedical Sciences(FMCB) University of AlgarveGambelas CampusFaroPortugal

With people living longer,the societal impact of age-related cognitive decline is becoming more pronounced(Crimmins,2015).Thus,it is increasingly important to comprehend the cognitive shifts linked to aging-whether th... 详细信息

关键词： bridges becoming insight