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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.

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Implementation of a New Solution for the Preservation of Anatomical Specimens Made of Non-Toxic Substances

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Open Journal of Veterinary Medicine 2024年第3期14卷 56-67页

作者： Ma Reyes Pichardo-Molinero Samantha Jardon-Xicotencatl Misael R. Oliver-González Carlos G. García-Tovar Laboratorio de Apoyo Técnico a la Anatomía Facultad de Estudios Superiores Cuautitlán Universidad Nacional Autónoma de México Estado de México Mexico Unidad de Investigación Multidisciplinaria L4 (Morfología Veterinaria y Biología Celular) Facultad de Estudios Superiores Cuautitlán Universidad Nacional Autónoma de México Estado de México Mexico

The preservation of anatomical pieces in Veterinary Anatomy is essential since it is not possible to dissect all domestic species. Most techniques use reagents with high levels of toxicity such as formaldehyde. The objective of this work was to develop a new preservation technique that uses reagents with zero toxicity and that allows obtaining preserved pieces suitable for anatomical studies. The alcohol propylene glycol technique was developed, the method of which uses a fixation step with alcohol, sodium chloride, commercial vinegar and subsequently the impregnation of the preservation solution made from propylene glycol and commercial vinegar, which are non-toxic. As a result of this work, adequately preserved sheep hearts were obtained that preserved their morphology with slight changes in size and weight, which did not affect their external and internal anatomical structure. Its coloration was not substantially affected, remaining a little lighter. The pieces obtained showed flexibility which allowed dissections to be carried out. The time to develop the technique was 20 days. A comparative study was carried out with the phenolated glycerin technique that uses toxic reagents (formaldehyde and phenol) and the pieces obtained with the alcohol propylene glycol technique were of better quality, observing that the pieces with phenolated glycerin tend to darken and are more rigid. And the time to develop the technique is 24 days. In conclusion, a preservation technique for anatomical pieces was developed that allowed the preservation of the organs under study, which allow their use for anatomical studies, and which have been preserved without changes until the time of this publication (8 months) and there are pieces preserved with this technique for 2 years.

关键词： Veterinary Anatomy Heart Preservation Techniques Alcohol Propylene Glycol Technique Fixation Necropsy Toxic Chemicals

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Semi-exact Solutions of Konwent Potential

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Communications in Theoretical Physics 2019年第2期71卷 231-236页

作者：董茜董世山 Eduardo Hernández-Márquez Ramón Silva-Ortigoza 孙国华董世海 Laboratorio de Información Cuántica CIDETEC Instituto Politécnico NacionalUPALM Information and Engineering College Dalian University área de Mecatrónica CIDETEC Instituto Politécnico NacionalUPALM Catedrática CONACYT CIC Instituto Politécnico Nacional

In this work we study the quantum system with the symmetric Konwent potential and show how to find its exact solutions. We find that the solutions are given by the confluent Heun function. The eigenvalues have to be calculated numerically because series expansion method does not work due to the variable z ≥ 1. The properties of the wave functions depending on the potential parameter A are illustrated for given potential parameters V_0 and a. The wave functions are shrunk towards the origin with the increasing |A|. In particular, the amplitude of wave function of the second excited state moves towards the origin when the positive parameter A decreases. We notice that the energy levels ε_i increase with the increasing potential parameter |A| ≥ 1, but the variation of the energy levels becomes complicated for |A| ∈(0, 1), which possesses a double well. It is seen that the energy levels ε_i increase with |A| for the parameter interval A ∈(-1, 0), while they decrease with |A| for the parameter interval A ∈(0, 1).

关键词： exact solution Konwent potential confluent Heun function double well potential

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Gravity Fault Subsidence and Beach Ridges Progradation in Quinta-Cassino (RS) Coastal Plain, Brazil

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Open Journal of Geology 2024年第2期14卷 177-195页

作者： Bruno Silva da Fontoura Adelir José Strieder Iran Carlos Stalliviere Corrêa Paulo Rogério Mendes Alexandre Felipe Bruch Angélica Cirolini Programa de Pós-Graduaç &#227o em Geoci&#234ncias (PPGeo) Instituto de Geoci&#234ncias UFRGS Porto Alegre Brazil Engenharia Geológica Centro de Engenharias UFPel Pra&#231a Domingos Rodrigues 2 Pelotas Brasil HIDROSERV-Serviç os Geológicos e Geofísicos Ltda. Rua Senegal 152 Porto Alegre Brazil Colégio politécnico UFSM Santa Maria Brasil

Ground penetrating radar (GPR) surveys have being applied to investigate very near-surface stratification of sedimentary units in coastal plains and to define their depositional conditions. This paper presents, however, low-frequency GPR survey to investigate fault-related depositional systems at greater depths. The Quinta-Cassino area in the Rio Grande do Sul Coastal Plain (RGSCP, Brazil) shows a wide strandplain that is made off by very long, continuous, and linear geomorphic features (beach ridges). This strandplain extends for ~70 km southward. The beach ridges show low-angle truncations against the Quinta escarpment, and also truncations in the strandplain. The traditional approach points that RGSCP was developed by juxtaposition of four lagoons/barrier systems as consequence of sea level changes;previous model assumes that no deformational episode occurred in RGSCP. The geophysical and geological surveys carried out in this area showed the existence of listric fault controlling the beach ridges in the escarpments and hanging-wall blocks. The radargrams could distinguish Pleistocene basement unit anticlockwise rotation, thickening of beach ridges radarfacies close to listric normal faults, and horst structures. These deformational features indicate that the extensional zone of a large-scale gravity-driven structure controlled the mechanical subsidence, the Holocene sedimentation and its stratigraphic and geomorphic features in the Quinta-Cassino area to build up an asymmetric delta. The results point to a new approach in dealing with RGSCP Holocene evolution.

关键词： Gravity Tectonics Normal Faults Ground Penetrating Radar Survey Beach-Ridges Progradation

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A Structural and Morphological Study of LiCo_1-XSm_XO_Y Powders Obtained by the Sol-Gel Method

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Advances in Nanoparticles 2022年第1期11卷 1-12页

作者： Víctor H. Colín Calderón Antonieta García Murillo Felipe de Jesus Carrillo Romo Arturo Cervantes Tobón instituto politécnico nacional CIITEC Cerrada de Cecati s/n Azcapotzalco Santa Catarina México instituto politécnico nacional-ESIQIE Av. Instituto Politécnico Nacional s/n. Mexico City México

In this study, the synthesis of LiCo1-XSmXOy powders (X = 0.002, 0.004, 0.006, 0.008, and 0.1) by the sol-gel method and the influence of Sm on their structural and morphological properties is reported for the first time. The results of x-ray diffraction (XRD) studies show that LiCoO2 powders synthesized at temperatures up to 700°C present a characteristic hexagonal crystalline phase of the α-NaFeO2 type (space group R-3m), revealing a shift in the (0 0 3) Bragg reflection, which reflects the presence of Sm in the crystalline structure. The morphology was spheroidal and, on average, 122 nm in size. Based on the data obtained, LiCo1-XSmXOy powders (X = 0.002, 0.004, 0.006, 0.008, and 0.1) show promise as a material for use in the cathodes of lithium-ion batteries.

关键词： Cathode Batteries Samarium Sol-Gel Nanoparticles

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Liver disorders in COVID-19,nutritional approaches and the use of phytochemicals

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World Journal of Gastroenterology 2021年第34期27卷 5630-5665页

作者： Nancy Vargas-Mendoza Jazmín García-Machorro Marcelo Angeles-Valencia Marlet Martínez-Archundia Eduardo Osiris Madrigal-Santillán Ángel Morales-González Liliana Anguiano-Robledo JoséA Morales-González Laboratorio de Medicina de Conservacion Instituto Politécnico NacionalMéxico 11340Mexico Laboratorio de Diseño y Desarrollo de Nuevos Fármacos e Innovación Biotécnológica Instituto Politécnico NacionalMéxico 11340Mexico Superior de Medicina Instituto Politécnico NacionalMéxico 11340Mexico Escuela Superior de Cómputo Instituto Politécnico NacionalMéxico 07738Mexico Laboratorio de Farmacología Molecular Instituto Politécnico NacionalMéxico 11340Mexico Laboratorio Medicina de Conservación Escuela Superior de MedicinaInstituto Politécnico NacionalMéxico 11340Mexico

Coronavirus disease 2019(COVID-19),which is caused by severe acute respiratory syndrome-coronavirus-2(SARS-CoV-2),has affected millions of people globally.It was declared a pandemic by the World Health Organization in March 2020.The hyperinflammatory response to the entry of SARS-CoV-2 into the host through angiotensin-converting enzyme 2 is the result of a“cytokine storm”and the high oxidative stress responsible for the associated symptomatology.Not only respiratory symptoms are reported,but gastrointestinal symptoms(diarrhea,vomiting,and nausea)and liver abnormalities(high levels of aspartate aminotransferase,alanine aminotransferase transaminases,and bilirubin)are observed in at least 30%of patients.Reduced food intake and a delay in medical services may lead to malnutrition,which increases mortality and poor outcomes.This review provides some strategies to identify malnutrition and establishes nutritional approaches for the management of COVID-19 and liver injury,taking energy and nutrient requirements and their impact on the immune response into account.The roles of certain phytochemicals in the prevention of the disease or as promising target drugs in the treatment of this disease are also considered.

关键词： COVID-19 Infection Liver Nutrition therapy Phytochemicals

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Vanadium mineralization at Los Chihuidos sediment-hosted Cu-V deposit,Neuquén Basin,Argentina:An approach to vanadium ore forming processes

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Geoscience Frontiers 2024年第1期15卷 225-246页

作者： Ana L.Rainoldi Daniel Beaufort Marta B.Franchini Adolfo Giusiano Sabine Petit Patricia Patrier M.Josefina Pons Dpto.de Geología Universidad Nacional del Sur(UNS)8000 Bahía BlancaArgentina Consejo nacional de Investigaciones Científicas y Técnicas Centro Patagónico de Estudios MetalogenéticosArgentina Universitéde Poitiers IC2MPCNRS-UMR 7285HydrasaF-86022 Poitiers CedexFrance Universidad nacional del Comahue Facultad de IngenieríaDepartamento de Geología y Petróleo8300 NeuquénArgentina Consultant Geologist 8300 NeuquénArgentina Universidad nacional de Río Negro Instituto de Investigación en Paleobiología y GeologíaRío NegroArgentina

Vanadium mineralization at Los Chihuidos deposit of the Neuquén Basin is linked to the development of a redox front system related to the inflow of hydrocarbons into the red sandstone of the Huincul Formation.Interaction of hydrocarbons with oxidized red beds and connate water generated redox reactions where hematite was dissolved due to iron reduction resulting in the discoloration of the red strata.At the contact between oxidized red sandstone and reduced white sandstone,precipitation of specific mineral phases resulted in the V ore with minor amounts of Cu.With the implementation of the redox interface,abundant V-montmorillonite and V-hematite precipitated at the more oxidizing conditions and Cu-V-corrensite-type at the more reducing conditions of the redox front.As the redox front advanced with fluids constantly migrating into the reservoir,more reducing conditions were stablished,promoting chloritization and minor illitization with V-Cu incorporation and continuous upgrading of the ore.Main ore mineralogy consists of clay minerals including V-bearing montmorillonite,Cu-V-corrensite-type,V-di-trioctahedral chlorite and Cu-tri-trioctahedral chlorite with minor V-illite-smectite mixed-layer minerals and associated secondary V-hematite.Chloritization over illitization was favored due to high amounts of Fe and Mg in detrital clasts and in connate fluids and by low K availability related to low amounts of detrital K-feldspar.The spatial transition of V and/or Cu bearing clay minerals observed through the mineralized redox front at Los Chihuidos deposit(kaolinite→smectite→illite/smectite→corrensite-type→di-trioctahedral-chlorite→tri-trioctahedral-chlorite)and the related variation of V-Cu concentrations in bulk rock are indicative of increasing pH and decreasing Eh of resident solutions from red to white sandstones during the hypogene mineralization process.Late influx of Cu-rich oxidized basinal brines precipitated main copper ore with Cu-sulfides in the white sandstone up to the contact with the redox front in co

关键词： Clay minerals V-chlorite Redox front Bleaching Hydrocarbons

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Review: Neuronal Differentiation Protocols of Mesenchymal Stem Cells

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Advances in Bioscience and Biotechnology 2022年第1期13卷 15-71页

作者： Miguel A. Jiménez-Acosta Lory Jhenifer Rochín Hernández Mayte Lizeth Padilla Cristerna José Tapia-Ramírez Marco A. Meraz-Ríos Department of Molecular Biomedicine Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional Instituto Politécnico Nacional México City México Department of Genetic and Molecular Biology Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional Instituto Politécnico Nacional México City México

Mesenchymal stem cells (MSCs) are self-renewing cells found in almost all postnatal organs and tissues in the perivascular region. These cells present multiple characteristics that make them candidates to be applied in cell therapy for neurodegenerative diseases, such as their secretory action, migration to the lesion area, and immunomodulatory potential. These cells have a high capacity for mesodermal differentiation;however, numerous studies have shown that MSCs can also differentiate into neurons. However, despite positive results in multiple trials in which undifferentiated MSCs transplanted into animal models of neurodegenerative diseases, some studies suggest that the therapeutic effects obtained are enhanced by the use of MSCs differentiated towards the neuronal lineage before transplant. In this sense, there are several methods to induce in vitro reprogramming of MSCs towards the neuronal lineage, including chemical substances, growth factors, cocultures with neural lineage cells, transfection of genes, miRNAs, etc., and small molecules stand out. Therefore, this article compares multiple experimental tests in which these inducers promote neuronal differentiation of MSCs and identify those methods that originate an optimal neuronal differentiation. The analysis includes the percentage of differentiation, maturation, expression of neuronal markers, functionality, and cell survival considering the intrinsic characteristics of the MSCs used as the tissue of origin and the species from which they were isolated.

关键词： Mesenchymal Stem Cells Transdifferentiating Neuronal Differentiation Small Molecules miRNA Neural Induction

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Evaluate More General Integrals Involving Universal Associated Legendre Polynomials via Taylor's Theorem

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Communications in Theoretical Physics 2017年第8期67卷 177-180页

作者： G.Yaez-Navarro 孙国华孙东升陈昌远董世海 ESFM Instituto Politécnico Nacional Edificio 9 Unidad Profesional ALM Catedrtica CONACyT CIC Instituto Politécnico NacionalUPALM New Energy and Electronic Engineering Yancheng Teachers University Laboratorio de Información Cuntica CIDETEC Instituto Politécnico Nacional Unidad Profesional ALM

A few important integrals involving the product of two universal associated Legendre polynomials P_(l′)^(m′)(x),P_k^n′~′(x)and x^(2a)(1-x^2)^(-p-1),x^b(1±x)^(-p-1)and x^c(1-x^2)^(-p-1)(1±x)are evaluated using the operator form of Taylor’s theorem and an integral over a single universal associated Legendre polynomial.These integrals are more general since the quantum numbers are unequal,i.e.l~′≠k~′and m~′≠n~′.Their selection rules are also given.We also verify the correctness of those integral formulas numerically.

关键词：数值积分公式勒让德多项式泰勒定理估计选择规则量子数伴随

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Liver histological changes and lipid peroxidation in the amphibian Ambystoma mexicanum induced by sediment elutriates from the Lake Xochimilco

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Journal of Environmental Sciences 2016年第8期28卷 156-164页

作者： Esperanza Ortiz-Ordonez Eugenia López-López Jacinto Elías Sedeno-Díaz Esther Uría Ignacio Andrés Morales María Estela Pérez Mineko Shibayama instituto politécnico nacional Depto.de Formación Básica e InterdisciplinariaCICS-USTAv.de los Maestros s/n.Col.Sto instituto politécnico nacional Laboratorio de Evaluación de la Salud de Ecosistemas AcuáticosENCBProl.de Carpio y Plan de Ayala s/n.Col.Sto instituto politécnico nacional Coordinación Politécnica para la SustentabilidadEdificio de la Biblioteca Nacional3er PisoAv.Instituto Politécnico Nacional s/nesq.Wilfrido MassieuCol instituto politécnico nacional Laboratorio de HistologíaENCBProl.de Carpio y Plan de Ayala s/n.Col.Sto Unidad de Servicio Académico Acuario BiologíaFacultad de CienciasUniversidad Autónoma de MéxicoCiudad Universitaria Laboratorio de Infectómica Centro de Investigación y de Estudios Avanzados del IPNAv.Instituto Politécnico Nacional

Lacustrine sediments accumulate pollutants that input from the lake watershed and can be released to the water column by sediment resuspension; thus, pollutants can change their bioavailability and exert adverse effects to aquatic biota. Shallow-urban lakes are particularly susceptible to receive pollutants from urban discharges and sediment resuspension. Lake Xochimilco, in Mexico City, an urban-shallow lake, faces multiple problems： urban sprawl, overexploitation of aquifers, drying of springs, discharge of wastewater from treatment plants, and sediment resuspension. The aquatic biota living in this ecosystem is continuously exposed to the release of pollutants from the sediments. We assessed the risk that pollutants released from sediments from Lake Xochimilco, Touristic（TZ） and Agriculture zone（AZ）, can exert on a native amphibian species of the lake（Ambystoma mexicanum） through exposure bioassays to sediment elutriates. We evaluate alterations in the amphibian by three approaches： biochemical（level of lipid peroxidation,LPO）, cellular（ultrastructure） and the liver histology of A. mexicanum and we compare them with a batch control. Additionally, we assessed heavy metals（Pb, Cd and Hg） in elutriates.Elutriates from TZ showed the highest concentrations of the metals assessed. Organisms exposed to sediment elutriates from either study sites showed higher LPO values than control organisms（p 〈 0.05）. Organisms exposed to elutriates from the TZ showed the most conspicuous damages： hepatic vasodilation of sinusoids, capillaries with erythrocytes,leukocyte infiltration and cytoplasmic vacuolation in hepatocytes. The biological responses assessed reflected the risk that faces A. mexicanum when is exposed for prolonged periods to sediment resuspension in Lake Xochimilco.

关键词： Elutriates Amphibian Liver Histological alterations Ultrastructure Oxidative stress Metals Urban lake

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