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Exploring the size of Andean condor foraging groups along an altitudinal and latitudinal gradient in the Tropical Andes: Ecological and conservation implications

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Current Zoology 2024年第2期70卷 225-232页

作者： diego Mendez Felix Hernan Vargas JoséHernan Sarasola Pedro P.Oleaa Departamento de Ecologia Universidad Autonoma de MadridCalle Darwin 228049MadridSpain Museo Nacional de Historia Natural Calle 26 s/nCota CotaLa PazBolivia The Peregrine Fund 5668 West Flying Hawk LaneBoiseID 83709USA Centro para el Estudio y Conservacion de Aves Rapaces en Argentina(CECARA) Universidad Nacional de La PampaAvda Uruguay 1516300 Santa RosaLa PampaArgentina Instituto de las Ciencias Ambientales y de la Tierra de La Pampa(INCITAP-CONICET) Avda.Uruguay 1516300 Santa RosaLa PampaArgentina Centro de Investigacion en Biodiversidad y Cambio Global(CIBC-UAM) Universidad Autonoma de MadridMadridCalle Darwin 228049Madrid Snain

Patterns of variation in the size of vulture foraging groups,and their ecological causes and consequences,remain litle explored despite strong links with the carrion recycling service that this key functional group provides.We documented the group size-frequency pattern of Andean con-dors Vultur gryphus gathered to feed on 42 equine carcasses experimentally placed in Bolivia,between 2012 and 2019,along an elevation range of 1,300-4,500 m asl.Based on the location(altitude and latitude)of the foraging groups,we examined the relationship between their size and species'population parameters(size and trend),habitat conditions,and livestock carcass availability and predictability.Condors utilized a high frequency(93%)of carcasses forming groups that ranged from 1 to 80 individuals(mean=25,median=18)and shaped a"lazy-J curve"typical pattern of size-frequency distribution whereby few groups(5,12%)were large(>55 individuals)and most(21,50%)were relatively small(<19 individuals).Group size related to altitude in that most larger groups formed at lower sites(below c.3,000 m asl),likely following an altitudinal gradient whereby larger groups are more likely to form around larger carcasses(i.e.,cattle),which are more likely to occur at lower elevations.Regardless of population size,group size could be an adaptive response of condors via local enhancement for improving individual scavenging efficiency.Many information gaps on this topic still exist,thus we provide a set of questions to address them,especially amidst the unrestricted impacts of human activities that condition vulture survival globally.

关键词： condor andino fusion-fission dynamics group size scavenger social foraging vultures.

Physical exercise and synaptic protection in human and pre-clinical models of multiple sclerosis

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Neural Regeneration Research 2024年第8期19卷 1768-1771页

作者： Federica Azzolini Ettore Dolcetti Antonio Bruno Valentina Rovella diego Centonze Fabio Buttari Unit of Neurology IRCCS NeuromedPozzilliItaly Department of System Medicine University of Tor VergataRomeItaly Synaptic Immunopathology Lab Department of Systems MedicineTor Vergata UniversityRomeItaly

In multiple sclerosis,only immunomodulato ry and immunosuppressive drugs are recognized as disease-modifying therapies.Howeve r,in recent years,several data from pre-clinical and clinical studies suggested a possible role of physical exe rcise as disease-modifying therapy in multiple sclerosis.Current evidence is sparse and often conflicting,and the mechanisms underlying the neuroprotective and antinflammatory role of exercise in multiple sclerosis have not been fully elucidated.Data,mainly derived from pre-clinical studies,suggest that exe rcise could enhance longterm potentiation and thus neuroplasticity,could reduce neuroinflammation and synaptopathy,and dampen astrogliosis and microgliosis.In humans,most trials focused on direct clinical and MRI outcomes,as investigating synaptic,neuroinflammato ry,and pathological changes is not straightfo rward compared to animal models.The present review analyzed current evidence and limitations in research concerning the potential disease-modifying therapy effects of exercise in multiple sclerosis in animal models and human studies.

关键词： disease-modifying behaviour endocannabinoid system long-term potentiation multiple sclerosis neuroplasticity neuroprotection physical exercise synaptopathy

Temporal stability and directional change in a color cline of a marine snail from NW Spain

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Current Zoology 2024年第2期70卷 163-173页

作者： Juan Gefaell Ramon Vigo A.Honorato Gonzalez-Vazquez Juan Galindo Emilio Rolan-alvarez Centro de Investigacion Marina Universidade de VigoDepartamento de BioquimicaGenetica e Inmunologia36310 VigoSpain

The evolution and maintenance of color clines is a classic topic of research in evolutionary ecology.However,studies analyzing the temporal dynamics of such clines are much less frequent,due to the difficulty of obtaining reliable data about past color distributions along environmen-tal gradients.In this article,we describe a case of decades-long temporal stability and directional change in a color cline of the marine snail Littorina saxatilis along the coastal inlet of the Ria de Vigo(NW Spain).L.saxatilis from this area shows a clear color cline with 3 distinct areas from the innermost to the more wave-exposed localities of the Ria:the inner,protected localities show an abundance of fawn-like individuals;the intermediate localities show a high diversity of colors;and the outer,wave-exposed localities show populations with a high frequency of a black and lineated morph.We compare data from the 1970s and 2022 in the same localities,showing that the cline has kept relatively stable for at least over half a century,except for some directional change and local variability in the frequency of certain morphs.Multiple regression analyses and biodiversity measures are presented to provide clues into the selective pressures that might be involved in the maintenance of this color cline.Future research avenues to properly test the explanatory power of these selective agents as well as the possible origins of the cline are discussed.

关键词： clinal variation color polymorphism ecological gradient Littorina saxatilis natural selection wave exposure.

Brent vs.West Texas Intermediate in the US petro derivatives price formation

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Petroleum Science 2024年第1期21卷 729-739页

作者： Alejandro Almeida Antonio A.Golpe Juan Manuel Martín-alvarez Jose Carlos Vides Universidad Internacional de La Rioja Department of Quantitative Methods for Economics and BusinessLa RiojaSpain University of Huelva Department of Economics and Centro de Estudios Avanzados en FisicaMatematicas y Computacion and ICEIHuelvaSpain Complutense University of Madrid Department of Applied and Structural Economics and History and ICEIMadridSpain

In this paper,we apply the spatial panel model to explore the relationship between the dynamic of two types of crude oil prices(WTI and Brent crude oil)and their refined products over time.Considering the turbulent months of 2011,when Cushing Oklahoma had reached capacity and the crude oil export ban removal in 2015 as breakpoints,we apply this method both in the full sample and the three resultant regimes.First,results suggest our results show that both WTI and Brent display very similar behaviour with the refined products.Second,when attending to each regime,results derived from the first and third regimes are quite similar to the full sample results.Therefore,during the second regime,Brent crude oil became the benchmark in the petrol market,and it influenced the distillate products.Furthermore,our model can let us determine the price-setters and price-followers in the price formation mechanism through refined products.These results possess important considerations to policymakers and the market participants and the price formation.

关键词： Crude oil prices Spatial panel model Refined products Price formation

Interplay between mesenchymal stromal cells and the immune system after transplantation: implications for advanced cell therapy in the retina

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Neural Regeneration Research 2024年第3期19卷 542-547页

作者： María Norte-Muñoz David García-Bernal diego García-Ayuso Manuel Vidal-Sanz Marta Agudo-Barriuso Grupo de Investigación Oftalmología Experimental Departamento de OftalmologíaOptometríaOtorrinolaringología y Anatomía PatológicaFacultad de MedicinaUniversidad de MurciaInstituto Murciano de Investigación Biosanitaria(IMIB)Campus de Ciencias de la Salud30120 MurciaSpain Grupo de Investigación Trasplante Hematopoyético y Terapia celular Departamento de Bioquímica e Inmunología.Facultad de MedicinaUniversidad de MurciaInstituto Murciano de Investigación Biosanitaria(IMIB)Campus de Ciencias de la Salud30120 MurciaSpain

Advanced mesenchymal stromal cell-based therapies for neurodegenerative diseases are widely investigated in preclinical models.Mesenchymal stromal cells are well positioned as therapeutics because they address the underlying mechanisms of neurodegeneration,namely trophic factor deprivation and neuroinflammation.Most studies have focused on the beneficial effects of mesenchymal stromal cell transplantation on neuronal survival or functional improvement.However,little attention has been paid to the interaction between mesenchymal stromal cells and the host immune system due to the immunomodulatory properties of mesenchymal stromal cells and the long-held belief of the immunoprivileged status of the central nervous system.Here,we review the crosstalk between mesenchymal stromal cells and the immune system in general and in the context of the central nervous system,focusing on recent work in the retina and the importance of the type of transplantation.

关键词： adaptive immunity cell therapy central nervous system immune system innate immunity mesenchymal stromal cells neuroregeneration preclinical studies retina transplantation

Laser-induced plasma formation in water with up to 400 mJ double-pulse LIBS

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Plasma Science and Technology 2024年第1期26卷 93-100页

作者： Marion HENKEL Michelle SIEMENS Ralf METHLING Benjamin EMDE Jörg HERMSDORF Steffen FRANKE diego GONZALEZ Leibniz Institute for Plasma Science and Technology(INP) Felix-Hausdorff-Straße 2Greifswald 17489Germany Laser Zentrum Hannover e.V.(LZH) Hollerithallee 8Hannover 30419Germany

Double-pulse LIBS is a promising technique for deep-sea applications.LIBS measurements in shallow water with up to 400 mJ each pulse were done to select laser parameters which promote optimized spectral line emission from plasma even at elevated pressures,where line broadening until loss of most of the spectral information can occur.Optical emission spectroscopy,using a Czerny-Turner spectrometer,has been applied to investigate the dependence of the emitted radiation on laser parameters and hydrostatic pressure.It has been found,that higher laser pulse energies,especially with short pulse delay as required in high water pressure,can also have an adverse effect on the measured spectrum.

关键词： double-pulse LIBS underwater plasma formation emission spectrosocpy

MicroRNAs in hepatocellular carcinoma treatment:Charting the path forward

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World Journal of Gastroenterology 2024年第11期30卷 1470-1474页

作者： Hong T Lin Antonio F alvarez Castaneda Somashekar G Krishna Khalid Mumtaz Division of Gastroenterology Hepatology and NutritionDepartment of MedicineThe Ohio State University Wexner Medical CenterColumbusOH 43210United States

MicroRNAs(miRNAs)are recognized for their involvement in the regulation of gene expression and exhibit significant potential in both the prognostic assessment and treatment of hepatocellular carcinoma(HCC).HCC,like other tumors,seldom occurs in isolation;instead,it evolves within a microenvironment featuring oncogenic and tumor-suppressive elements.When combined with suitable delivery vehicles,miRNA technology provides the capability to directly engage with these elements,thereby hindering tumor formation and progression.Ongoing research in this domain holds the promise of enabling a more efficacious and multi-modal treatment approach for HCC in the near future.

关键词： Hepatocellular carcinoma Tumor microenvironment MicroRNA Mesenchymal stem cell Exosome

AN OPTIMAL CONTROL PROBLEM FOR A LOTKA-VOLTERRA COMPETITION MODEL WITH CHEMO-REPULSION

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Acta Mathematica Scientia 2024年第2期44卷 721-751页

作者： Diana I.HERNÁNDEZ diego A.RUEDA-GOMEZ Élder J.VILLAMIZAR-ROA Universidad Industrial de Santander Escuela de MatemáticasA.A.678BucaramangaColombia

In this paper we study a bilinear optimal control problem for a diffusive Lotka-Volterra competition model with chemo-repulsion in a bounded domain of ℝ^(ℕ),N=2,3.This model describes the competition of two species in which one of them avoid encounters with rivals through a chemo-repulsion mechanism.We prove the existence and uniqueness of weak-strong solutions,and then we analyze the existence of a global optimal solution for a related bilinear optimal control problem,where the control is acting on the chemical signal.Posteriorly,we derive first-order optimality conditions for local optimal solutions using the Lagrange multipliers theory.Finally,we propose a discrete approximation scheme of the optimality system based on the gradient method,which is validated with some computational experiments.

关键词： Lotka-Volterra chemo-repulsion optimal control optimality conditions

Optimizing nutrition in hepatic cirrhosis:A comprehensive assessment and care approach

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World Journal of Gastroenterology 2024年第10期30卷 1313-1328页

作者： Osvely Mendez-Guerrero Anaisa Carranza-Carrasco Luis Alberto Chi-Cervera Aldo Torre Nalu Navarro-alvarez Department of Gastroenterology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico Clínica de Especialidades Gastrointestinales y Hepáticas Hospital Star MedicaMerida 97133YucatanMexico Molecular Biology Universidad Panamericana School of MedicineCampus MéxicoMexico City 03920Mexico Department of Surgery University of Colorado Anschutz Medical CampusDenverCO 80045United States

Cirrhosis is considered a growing cause of morbidity and mortality,which represents a significant public health problem.Currently,there is no effective treatment to reverse cirrhosis.Treatment primarily centers on addressing the underlying liver condition,monitoring,and managing portal hypertension-related complications,and evaluating the potential for liver transplantation in cases of decompensated cirrhosis,marked by rapid progression and the emer-gence of complications like variceal bleeding,hepatic encephalopathy,ascites,malnutrition,and more.Malnutrition,a prevalent complication across all disease stages,is often underdiagnosed in cirrhosis due to the complexities of nutritional assessment in patients with fluid retention and/or obesity,despite its crucial impact on prognosis.Increasing emphasis has been placed on the collaboration of nutritionists within hepatology and Liver transplant teams to deliver compre-hensive care,a practice that has shown to improve outcomes.This review covers appropriate screening and assessment methods for evaluating the nutritional status of this population,diagnostic approaches for malnutrition,and context-specific nutrition treatments.It also discusses evidence-based recommendations for supplementation and physical exercise,both essential elements of the standard care provided to cirrhotic patients.

关键词： Cirrhosis Nutritional diagnosis Treatment Diet Guidelines