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Freeze-thaw cycles and associated geomorphology in a post-glacial environment:current glacial,paraglacial,periglacial and proglacial scenarios at Pico de Orizaba volcano,Mexico

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Journal of Mountain Science 2024年第6期21卷 1954-1977页

作者： víctor soto Carlos M.WELSH R. Kenji YOSHIKAWA Hugo DELGADO GRANADOS Centro de Ciencias de la Tierra Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water and Environmental Research Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Department of Earth and Environmental Sciences Ludwig Maximilians UniversitätMunich 80333Germany

The glacial history of Pico de Orizaba indicates that during the Last Glacial Maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m asl.The retraction of the glacier has left behind an intense climatic instability that causes a high frequency of freeze-thaw cycles of great intensity;the resulting geomorphological processes are represented by the fragmentation of the bedrock that occupies the upper parts of the mountain.There is a notable lack of studies regarding the fragmentation and erosion occurring in tropical high mountains,and the associated geomorphological risks;for this reason,as a first stage of future continuous research,this study analyzes the freezing and thawing cycles that occur above 4000 m asl,through continuous monitoring of surface ground temperature.The results allow us to identify and characterize four zones:glacial,paraglacial,periglacial and proglacial.It was found that the paraglacial zone presents an intense drop of temperature,of up to~9℃ in only sixty minutes.The rock fatigue and intense freeze-thaw cycles that occur in this area are responsible for the high rate of rock disintegration and represent the main factor of the constant slope dynamics that occur at the site.This activity decreases,both in frequency and intensity,according to the distance to the glacier,which is where the temperature presents a certain degree of stability,until reaching the proglacial zone,where cycles are almost non-existent,and therefore there is no gelifraction activity.The geomorphological processes have resulted in significant alterations to the mountain slopes,which can have severe consequences in terms of risk and water.

关键词： Freeze-Thaw Gelifraction Mountain mechanical erosion Periglacial geomorphology Postglacial scenarios

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Biomaterial engineering strategies for modeling the Bruch's membrane in age-related macular degeneration

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Neural Regeneration Research 2024年第12期19卷 2626-2636页

作者： Blanca Molins Andrea Rodríguez víctor Llorenç Alfredo Adán Group of Ocular Inflammation:Clinical and Experimental Studies Institut d’Investigacions Biomèdiques AgustíPi I Sunyer(IDIBAPS)BarcelonaSpain Institut Clínic d’Oftalmologia(ICOF) Hospital Clínic BarcelonaSpain

Age-related macular degeneration,a multifactorial inflammatory degenerative retinal disease,ranks as the leading cause of blindness in the elderly.Strikingly,there is a scarcity of curative therapies,especially for the atrophic advanced form of age-related macular degeneration,likely due to the lack of models able to fully recapitulate the native structure of the outer blood retinal barrier,the prime to rget tissue of age-related macular degeneration.Standard in vitro systems rely on 2D monocultures unable to adequately reproduce the structure and function of the outer blood retinal barrier,integrated by the dynamic interaction of the retinal pigment epithelium,the Bruch's membrane,and the underlying choriocapillaris.The Bruch's membrane provides structu ral and mechanical support and regulates the molecular trafficking in the outer blood retinal barrier,and therefo re adequate Bruch's membrane-mimics are key for the development of physiologically relevant models of the outer blood retinal barrie r.In the last years,advances in the field of biomaterial engineering have provided novel approaches to mimic the Bruch's membrane from a variety of materials.This review provides a discussion of the integrated properties and function of outer blood retinal barrier components in healt hy and age-related macular degeneration status to understand the requirements to adequately fabricate Bruch's membrane biomimetic systems.Then,we discuss novel materials and techniques to fabricate Bruch's membrane-like scaffolds for age-related macular degeneration in vitro modeling,discussing their advantages and challenges with a special focus on the potential of Bruch's membrane-like mimics based on decellularized tissue.

关键词： age-related macular degeneration Bruch's membrane decellularization retinal pigment epithelium scaffold

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Myelin histology:a key tool in nervous system research

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Neural Regeneration Research 2024年第2期19卷 277-281页

作者： Óscar Darío García-García víctor Carriel Jesús Chato-Astrain Department of Histology Tissue Engineering GroupUniversity of Granada&Instituto de Investigación Biosanitaria ibs.GRANADAGranadaSpain

The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve fibers.Due to the complex structure and composition of myelin,various histological techniques have been developed over the centuries to evaluate myelin under normal,pathological or experimental conditions.Today,methods to assess myelin integrity or content are key tools in both clinical diagnosis and neuroscience research.In this review,we provide an updated summary of the composition and structure of the myelin sheath and discuss some histological procedures,from tissue fixation and processing techniques to the most used and practical myelin histological staining methods.Considering the lipoprotein nature of myelin,the main features and technical details of the different available methods that can be used to evaluate the lipid or protein components of myelin are described,as well as the precise ultrastructural techniques.

关键词： fluorescence microscopy histology light microscopy lipid histochemistry metallographic techniques myelin histochemistry myelin immunohistochemistry myelin structure&composition myelin ultrastructural evaluation tissue fixation&processing

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Cold and Fertile: Cryopreservation as an Innovative Tool in Addressing Challenges in Teratozoospermia

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Journal of Biosciences and Medicines 2024年第2期12卷 274-281页

作者： víctor Manuel soto-Márquez Jorge Mulia-Rodríguez Daniel Osorio-González Molecular Biophysics Laboratory Faculty of Sciences Autonomous University of State of Mexico Toluca Mexico

Teratozoospermia is an infertility issue that affects a significant number of couples of reproductive age. One of the potential causes contributing to the global decline in seminal quality includes factors such as diet, alcohol and tobacco consumption, high levels of stress, and environmental influences. This underscores the need to preserve the fertility of these patients through cryopreservation techniques. In this review, we explore the latest methods for freezing seminal samples, highlighting their advancements and advantages in addressing the challenge of perpetuating animal species, particularly in the context of human infertility.

关键词： Cryopreservation Teratozoospermia Infertility

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Bedrock outcropping in the accumulation zone of the largest glacier in Mexico(Glaciar Norte of Citlaltépetl),as evidence of a possible accelerated extinction

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Journal of Mountain Science 2023年第2期20卷 338-354页

作者： soto víctor Colegio de Geografía Facultad de EconomíaUniversidad VeracruzanaAv.Xalapa s/nObrero Campesina91020XalapaVer.México

The highest volcano in Mexico,at the same time the third largest mountain in North America(Citlaltépetl,5610 m a.s.l.),is home to the largest glacier in the country.Because of the extinction of the Popocatépetl glacier(5500 m a.s.l.)caused by eruptive activity,and the almost disappearance of the Iztaccíhuatl glaciers(5220 m a.s.l.)due to the lower elevation of the mountain,the Glaciar Norte of Citlatépetl has been the only glacier that has shown a certain degree of stability as a response to the altitude in which it is located.However,as occurs in almost all glaciers on the planet,the retreat of its glacier terminus has been continuous.Furthermore,during the last years the thickness of its upper part began to decrease rapidly until its bedrock was exposed for the first time in 2019.Due to its ecosystem importance and because it is the main glacier in Mexico,as well as the only one in the world located at latitude 19°N,in this work its current dimensions are updated,as well as the local climatology that governs the current state of the glacier is pointed out.The study was based on the analysis of high-resolution Sentinel-2 optical images,as well as through Sentinel-1 SAR images,with the support of climatological information from the study area.Therefore,the outcropping of the bedrock in the accumulation zone and the consequent horizontal retreat of the upper part of the glacier are documented;at the same time,the decrease in the thickness of the ice along it is noted.The rocky outcrop in the accumulation zone suggests that the flow dynamics of the ice towards the ablation zone will be considerably less,accelerating the retreat of the glacier terminus.Finally,the ascent of the glacial front to 5102 m a.***.l.and the modelled altitude of the equilibrium line to 5276 m a.***.l.are reported as a warning signal in terms of snow catchment and mass balance;likewise,the decrease of 23%of its surface is also indicated regarding the surface reduction monitoring that has been done until 2017.These findings may indicate that the

关键词： Bedrock outcrop Citlaltépetl glacier Glacial accumulation zone Glacier retreat Glacial thickness

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Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs víctor Cilleros-Mañé Laia Just-Borràs Marta Balanyà-Segura Aleksandra Polishchuk Laura Nadal Marta Tomàs Carolina Silvera-Simón Manel M.Santafé Maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and synapses.Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or strengthening.We have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse consolidation.The purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this process.In particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental competition.The dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific endings.We describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon terminals.The downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary synapses.Finally,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to reduce transmitter release and promote withdrawal o

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

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Exploring Alternatives to Create Digital Twins from and for Process Simulation

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Journal of Computer Science Research 2024年第1期6卷 16-30页

作者： Jaime Barbero-Sánchez Alicia Megía-Ortega víctor R.Ferro Jose-Luis valverde Department of Chemical Engineering University of Castilla La ManchaAvda.Camilo JoséCela 12Ciudad Real13071Spain Department of Chemical Engineering Autonomous University of MadridCantoblancoMadrid28049Spain

In this work,Digital Twins based on Neural Networks for the steady state production of styrene were generated.Thus,both the Aspen Technology AI Model Builder(alternative 1)and a homemade MS Excel vBA code connected to Aspen HYSYS and Aspen Plus(alternative 2)were used with this same aim.The raw data used for generating the Digital Twins were obtained from process simulations using Aspen HYSYS and/or Aspen Plus,which were connected through a recycle-like stream via automation for solving the entire simulation flowsheet.Aspen HYSYS was used for solving the pre-heating,reaction,and stabilization sections of the process whereas Aspen Plus ensured the computing of the separation and purification columns.Both alternatives led to an excellent prediction showing the capability of creating Digital Twins from and for process simulation.

关键词： Digital Twin Aspen Hybrid Model Builder Aspen HYSYS Aspen Plus Automation MS Excel-vBA

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Analysis of the Supply Chain in Industrial Companies in Guayaquil,Ecuador-A Secondary Publication

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Proceedings of Business and Economic Studies 2024年第1期7卷 242-255页

作者： Génesis Belén Linzán Soledispa Betty Janeth Soledispa Canarte víctor Alfonso ChávezSoledispa Oscar Rolando Fiallos González Universidad Politécnica Salesiana GuayaquilEcuador Universidad Estatal del Sur de Manabí ManabíEcuador Universidad Católica de Santiago de Guayaquil GuayaquilEcuador

This research clearly outlines the supply chain in a process of evolution and digital transformation,where the collaboration of its members is concentrated,having technological tools to help chain management.To analyze the advantages that this transformation produces in the supply chain,as well as its different processes,this study has a systemic perspective that involves precise elements for organizational development,such as the different phases of each process,operations,logistics,and distribution.It must be borne in mind that any strategy in industrial companies grants the automation of procedures in the supply chain and determines a product in any phase of production,making the organization more sensitive to any variation in orders.The methodology included a bibliographic and non-experimental review that allows a descriptive and analytical study,which details the various characteristics of the fact that is being investigated,collecting information through interviews with different people who are involved with industrial companies.Among the results obtained,it was identified that digital transformation helps reduce costs and generates greater profitability.In conclusion,it was obtained that the digital supply chain helps in each of the phases of the processes,these are supervised by devices that help to have fast and effective information.

关键词： Digital transformation Supply chain Industries 4.0 Sustainability

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Long-term effects of gestational diabetes mellitus on the pancreas of female mouse offspring

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World Journal of Diabetes 2024年第4期15卷 758-768页

作者： Enriqueta Muñoz-Islas Edgar David Santiago-SanMartin Eduardo Mendoza-Sánchez Héctor Fabián Torres-Rodríguez Laura Yanneth Ramírez-Quintanilla Christopher Michael Peters Juan Miguel Jiménez-Andrade Unidad Académica Multidisciplinaria Reynosa-Aztlán Universidad Autónoma de TamaulipasReynosa 88740TamaulipasMexico Department of Anesthesiology Wake Forest University School of MedicineWinston SalemNC 27101United States

BACKGROUND Prolonged fetal exposure to hyperglycemia may increase the risk of developing abnormal glucose metabolism and type-2 diabetes during childhood,adolescence,and adulthood;however,the mechanisms by which gestational diabetes mellitus(GDM)predisposes offspring to metabolic disorders remain unknown.AIM To quantify the nerve axons,macrophages,and vasculature in the pancreas from adult offspring born from mouse dams with GDM.METHODS GDM was induced by i.***.administration of streptozotocin(STZ)in ICR mouse dams.At 12 wk old,fasting blood glucose levels were determined in offspring.At 15 wk old,female offspring born from dams with and without GDM were sacrificed and pancreata were processed for immunohistochemistry.We quantified the density of sensory[calcitonin gene-related peptide(CGRP)]and tyrosine hydroxylase(TH)axons,blood vessels(endomucin),and macro-phages(CD68)in the splenic pancreas using confocal microscopy.RESULTS Offspring mice born from STZ-treated dams had similar body weight and blood glucose values compared to offspring born from vehicle-treated dams.However,the density of CGRP+and TH+axons,endomucin+blood vessels,and CD68+macrophages in the exocrine pancreas was significantly greater in offspring from mothers with GDM vs control offspring.Likewise,the microvasculature in the islets was significantly greater,but not the number of macrophages within the islets of offspring born from dams with GDM compared to control mice.CONCLUSION GDM induces neuronal,vascular,and inflammatory changes in the pancreas of adult progeny,which may partially explain the higher propensity for offspring of mothers with GDM to develop metabolic diseases.

关键词： Gestational diabetes mellitus Immunohistochemistry Confocal microscopy Pancreas Offspring

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Diversity of Saxicolous Lichens along an Aridity Gradient in Central México

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Phyton-International Journal of Experimental Botany 2022年第4期91卷 827-840页

作者： JoséCarmen soto-Correa Abraham Saldaña-vega víctor Hugo Cambrón-Sandoval Laura Concostrina-Zubiri Mariela Gómez-Romero Facultad de Ciencias Naturales Universidad Autónoma de QuerétaroQuerétaro73230México Departamento de Biología y Geología Física y Química Inorgánica Tulipán s/nUniversidad Rey Juan CarlosMóstolesMadrid28933España Cátedra CONACYT–Facultad de Biología Universidad Michoacana de San Nicolás de HidalgoMoreliaMichoacán58030México

Lichens are symbiotic organisms that comprise a fungus and a photosynthetic partner wich are recognized as a good indicator of climate change.However,our understanding of how aridity affects the diversity of saxicolous lichens in drylands is still limited.To evaluate the relationship between saxicolous lichen diversity and aridity in a central México dryland,a geographical transect was established of 100 km to build an aridity gradient in the semiarid zone of the State of Querétaro,Mexico,comprising ten sampling sites with a 10 km separation.Species richness,abundance and diversity of soil lichen species were recorded using two sampling methods:the quadrat-intercept and the line-intercept method,to compare their performance in assessing soil lichen diversity in drylands.The number of species and Shannon diversity of saxicolous lichens were higher at intermediate values of the aridity index(AI=0.10-0.34).Quadrat intercept and point intercept methods gave quite similar results,which means that the selected method does not influence the results in a significant way.This study confirms the role of saxicolous lichens as climate change indicators and reveals the importance of the sampling method selection in the evaluation of different parameters of soil lichen diversity in drylands.

关键词： Climate change drylands ecological indicators environmental stress precipitation temperature

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