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Application of a new reagent for analysis of oxygen presence in a lowcarbon steel wire rod

Journal of Iron and Steel Research(International) 2021年第6期28卷 729-738页

作者： M.I.Dávila-Pérez H.J.vergara-Hernández o.vázquez-gómez F.Reyes-Calderón E.López-Martínez J.M.Salgado-López National Technology of Mexico/T.I.of Morelia Morelia 58120MichoacanMexico National Council for Science and Technology CoNACYT Mexico City 03940Mexico Isthmus University Santo Domingo TehuantepecOaxaca 70760Mexico Engineering and Industrial Development Center CIDESI Santiago de Queretaro 76125QueretaroMexico

A microstructural analysis was performed to determine the presence of oxygen in a wire rod section of AISI 1008 steel with a surface mechanical failure produced during wire drawing.The failure zone was analyzed by comparison using three different attack reagents:alkaline sodium chromate(ASC),ASC with hydrogen peroxide and amyl alcohol,and a solution of nitric acid in ethyl alcohol.The reagents were applied in samples in the failure zone,showing different types of zones in regions with internal and superficial defects such as carbides,pores,cracks,deformation,and detachment zones,indicating the possible presence of oxygen.The areas identified were observed by means of an optical microscope and were correlated with the content of elements that were present in the region using a scanning electron microscope and a scattered X-ray energy spectrometer,which determined that the areas identified by chromate sodium correspond to regions with a high concentration of oxygen and slag-forming elements such as silicon,aluminum,and iron;this is associated with the presence of oxygen in the oxide form.It was also observed that the ASC and the modified ASC solution with hydrogen peroxide and amyl alcohol could identify areas with a high presence of oxides,while the nitric acid solution only identified the steel microstructure.The modified ASC solution is an alternative to identify the presence of chemical variants of oxygen because the co.ventional formulation is unstable and has a too short shelf life,and therefore,its application must be carried out at the time of preparation.

关键词： Etching Alkaline sodium chromate oxide presence Internal defect

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Hypothalamic circuits and aging:keeping the circadian clock updated

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Neural Regeneration Research 2024年第9期19卷 1919-1928页

作者： Rosa vázquez-Lizarraga Lucia Mendoza-viveros Carolina Cid-Castro Sareni Ruiz-Montoya Erick Carreño.vázquez Ricardo orozco-Solis Instituto Nacional de Medicina genómica(INMEgEN) México CityMéxico Centro de Investigacíon sobre el Envejecimiento Centro de Investigacíon y de Estudios Avanzados(CIE-CINVESTAV)México CityMéxico Instituto de Investigaciones Biomédicas Universidad Nacional Autónoma de México UNAMMéxico CityMéxico

over the past century,age-related diseases,such as cancer,type-2 diabetes,obesity,and mental illness,have shown a significant increase,negatively impacting overall quality of life.Studies on aged animal models have unveiled a progressive discoordination at multiple regulatory levels,including transcriptional,translational,and post-translational processes,resulting from cellular stress and circadian derangements.The circadian clock emerges as a key regulator,sustaining physiological homeostasis and promoting healthy aging through timely molecular coordination of pivotal cellular processes,such as stem-cell function,cellular stress responses,and inter-tissue communication,which become disrupted during aging.given the crucial role of hypothalamic circuits in regulating organismal physiology,metabolic control,sleep homeostasis,and circadian rhythms,and their dependence on these processes,strategies aimed at enhancing hypothalamic and circadian function,including pharmacological and non-pharmacological approaches,offer systemic benefits for healthy aging.Intranasal brain-directed drug administration represents a promising avenue for effectively targeting specific brain regions,like the hypothalamus,while reducing side effects associated with systemic drug delivery,thereby presenting new therapeutic possibilities for diverse age-related conditions.

关键词： aging astrocytes cellular stress responses circadian clock hypothalamus intranasal drug administration metabolic control nutrient sensor SIRT1 sleep homeostasis

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Targeting epidermal growth factor receptor signaling to facilitate cortical injury repair?

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Neural Regeneration Research 2024年第5期19卷 935-936页

作者： Ricardo gómez-oliva Pedro Nunez-Abades Carmen Castro Área de Fisiología Facultad de Medicina Universidad de CádizCadizSpain Instituto de Investigación e Innovación en Biomedicina de Cádiz CadizSpain Departamento de Fisiología Facultad de FarmaciaUniversidad de SevillaSevilleSpain

The existence of neural stem cells(NSC)in specific areas of the adult mammalian brain leads to the generation of new neurons invo.ved in homeostatic mechanisms.This is the case of the NSC of the subventricular zone(SvZ)that produces olfactory bulb(oB)neurons.These neurons integrate into circuits to modulate sensory information and participate in olfactory processing(Bragado Alonso et al.,2019).A series of hierarchical events need to take place to produce oB neurons from NSC of the SvZ.First,the activation of quiescent NSC is necessary to produce intermediate transit amplifying progenitors(TAP),which will generate neuroblasts.The latter are cells that maintain a proliferative phenotype while in an immature phase.However,once they initiate migration toward the oB,they progressively undergo their differentiation into neurons(Kjell et al.,2020).

关键词： ventricular maintain

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High Co_(2)permeation using a new Ce_(0.85)gd_(0.15)o_(2-δ)-LaNio_(3)composite ceramic–carbonate dual-phase membrane

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Journal of Environmental Sciences 2024年第6期140卷 219-229页

作者： Daniela gonzález-varela JFrancisco gómez-garcía gustavo Tavizon Heriberto Pfeiffer Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCd.UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMéxico Departamento de Física y Química Teórica Facultad de QuímicaUniversidad Nacional Autónoma de MéxicoCd.UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMéxico 不详

This work shows the synthesis,characterization and evaluation of dense-ceramic membranes made of Ce_(0.85)gd_(0.15)o_(2-δ)-LaNio_(3)(Cg-LN)composites,where the fluorite-perovskite ratio(Cg:LN)was varied as follows:75:25,80:20 and 85:15 wt.%.Supports were initially characterized by XRD,SEM and electrical conductivity(using vacuum and oxygen atmospheres),to determine the composition,microstructural and ionic-electronic conductivity properties.Later,supports were infiltrated with an eutectic carbonates mixture,producing the corresponding dense dual-phase membranes,in which Co_(2)permeation tests were conducted.Here,Co_(2)permeation experiments were performed from 900 to 700℃,in the presence and absence of oxygen(flowed in the sweep membrane side).Results showed that these composites possess high Co_(2)permeation properties,where the o_(2)addition significantly improves the ionic conduction on the sweep membrane side.Specifically,the gC80-LN20 composition presented the best results due to the following physicochemical characteristics:high electronic and ionic conductivity,appropriate porosity,interconnected porous channels,as well as thermal and chemical stabilities between the composite support and carbonate phases.

关键词： Co_(2)permeation Doped Ceo_(2) LaNio_(3) Impedance Ceramic carbonate membrane

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Pollen analysis reveals the effects of uncovered interactions,pollen-carrying structures,and pollinator sex on the structure of wild bee-plant networks

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Insect Science 2024年第3期31卷 971-988页

作者： Clément Tourbez Carmelo gómez-Martínez MiguelÁngel gonzalez-Estévez Amparo Lazaro Mediterranean Institute for Advanced Studies(UIB-CSIC) Global Change Research GroupEsporlesBalearic IslandsSpain Department of Biology Ecology AreaUniversity of the Balearic/slandsPalmaSpain

Pollination networks are increasingly used to model the complexity of interactions between pollinators and flowering plants in communities.Different methods exist to sample these interactions,with direct observations of plant-pollinator contacts in the field being by far the most common.Although the identification of pollen carried by pollinators allows uncovering interactions and increasing sample sizes,the methods used to build pollen-transport networks are variable and their effect on network structure remains unclear.To understand how interaction sampling influences the structure of networks,we analyzed the pollen found on wild bees from eight communities across Mallorca Island and investigated the differences in pollen loads between bee body parts(scopa vs.body)and sexes.We then assessed how these differences,as well as the uncovered interactions not detected in the field,influenced the structure of wild bee-plant networks.We identified a higher quantity and diversity of pollen in the scopa than in the rest of the female body,but these differences did not lead to differences in structure between plant-pollination(excluding scopa pollen)and bee-feeding interaction(including scopa pollen)networks.However,networks built with pollen data were richer in plant species and interactions and showed lower modularity and specialization(H2'),and higher nestedness than visitation networks based on field observations.Female interactions with plants were stronger compared to those of males,although not richer.Accordingly,females were more generalist(low d')and tended to be more central in interaction networks,indicating their more key role structuring pollination networks in comparison to males.our study highlights the importance of palynological data to increase the resolution of networks,as well as to understand important ecological questions such as the differences between plant-pollination and bee-feeding interaction networks,and the role of sexes in pollination.

关键词： palynology pollen-transport networks pollination role of bee sexes sampling methodology visitation networks

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Predicting intensive care unit-acquired weakness:A multilayer perceptron neural network approach

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World Journal of Clinical Cases 2024年第12期12卷 2023-2030页

作者： Carlos Martin Ardila Daniel gonzález-Arroyave Mateo Zuluaga-gómez Department of Basic Sciences University of AntioquiaMedellín 52-59Colombia Department of Surgery Pontificia Universidad BolivarianaMedellín 0057Colombia Department of Emergency Universidad Pontificia BolivarianaMedellín 0057Colombia

In this editorial,we comment on the article by Wang and Long,published in a recent issue of the World Journal of Clinical Cases.The article addresses the challenge of predicting intensive care unit-acquired weakness(ICUAW),a neuromuscular disorder affecting critically ill patients,by employing a novel processing strategy based on repeated machine learning.The editorial presents a dataset comprising clinical,demographic,and laboratory variables from intensive care unit(ICU)patients and employs a multilayer perceptron neural network model to predict ICUAW.The authors also performed a feature importance analysis to identify the most relevant risk factors for ICUAW.This editorial contributes to the growing body of literature on predictive modeling in critical care,offering insights into the potential of machine learning approaches to improve patient outcomes and guide clinical decision-making in the ICU setting.

关键词： Intensive care units Intensive care unit-acquired weakness Risk factors Machine learning Computer neural network

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Physical activity and amyloid beta in middle-aged and older adults:A systematic review and meta-analysis

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Journal of Sport and Health Science 2024年第2期13卷 133-144页

作者： María Rodriguez-Ayllon Patricio Solis-Urra Cristina Arroyo-ávila Miriam álvarez-ortega Pablo Molina-garcía Cristina Molina-Hidalgo Manuel gómez-Río Belinda Brown Kirk I.Erickson Irene Esteban-Cornejo Department of Epidemiology Erasmus University Medical Center RotterdamRotterdamGD 3015the Netherlands Department of Physical Education and Sports Faculty of Sport SciencesSport and Health University Research Institute(iMUDS)University of GranadaGranada 18071Spain Faculty of Education and Social Sciences Universidad Andres BelloVina del Mar 2531015Chile Department of Nuclear Medicine Virgen de las Nieves University HospitalInstitute of Biosanitary Research of Granada(IBS)Granada 18014Spain Physical Medicine and Rehabilitation Service Virgen de las Nieves University HospitalInstitute of Biosanitary Research of Granada(IBS)Granada 18014Spain Department of Psychology University of PittsburghPittsburghPA 15260USA Centre for Healthy Ageing Health Futures InstituteMurdoch UniversityMurdochWA 6150Australia School of Medical and Health Sciences Edith Cowan UniversityJoondalupWA 6027Australia Advent Health Research Institute Neuroscience Institute OrlandoOrlandoFL 32803USA Physiopathology of obesity and Nutrition Research Center(CIBERobn) Institute of Health Carlos Ⅲ(ISCⅢ)Madrid 28029Spain

Background:one of the pathological hallmarks distinguishing Alzheimer’s disease from other dementias is the accumulation of amyloid beta(Aβ).Higher physical activity is associated with decreased dementia risk,and one potential path could be through Aβlevels modulation.We aimed to explore the relationship between physical activity and Aβin middle-aged and older adults.Methods:A systematic search of PubMed,Web of Science,PsycINFo,Cochrane Central Register of Controlled Trials,and SPoRTDiscus was performed from inception to April 28,2022.Studies were eligible if they included physical activity and Aβdata in adults aged 45 years or older.Multi-level metaanalyses of intervention and observational studies were performed to examine the role of physical activity in modulating Aβlevels.Results:In total,37 articles were included(8 randomized controlled trials,3 non-randomized controlled trials,4 prospective longitudinal studies,and 22 cross-sectional studies).The overall effect size of physical activity interventions on changes in blood Aβwas medium(pooled standardized mean difference=-0.69,95%confidence interval(95%CI):-1.41 to 0.03;I^(2)=74.6%).However,these results were not statistically significant,and there were not enough studies to explore the effects of physical activity on cerebrospinal fluid(CSF)and brain Aβ.Data from observational studies were examined based on measurements of Aβin the brain using positron emission tomography scans,CSF,and blood.Higher physical activity was positively associated with Aβonly in the CSF(Estimate r=0.12;95%CI:0.05-0.18;I^(2)=38.00%).Conclusion:Physical activity might moderately reduce blood Aβin middle-aged and older adults.However,results were only near statistical significance and might be interpreted with caution given the methodological limitations observed in some of the included studies.In observational studies,higher levels of physical activity were positively associated with Aβonly in CSF.Therefore,further research is needed to understand the modulating role of physical act

关键词： Aging Cognitive impairment Dementia Exercise PET

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Ductal carcinoma in situ within a fibroadenoma:A case report and review of literature

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World Journal of Radiology 2024年第3期16卷 58-68页

作者： Yazmin olivares-Antúnez Yesika Janett Dávila-Zablah JoséRaúl vázquez-Ávila gabriela Sofía gómez-Macías María Teresa Mireles-Aguilar Margarita Lilia garza-Montemayor Department of Diagnostic Breast Imaging Center Hospital Zambrano HellionTecnológico de MonterreyNuevo León 66260Mexico Department of Patology Service Hospital San JoséTecnológico de MonterreyNuevo León 64710Mexico Department of Faculty of Medicine Hospital Universitario de la UANLNuevo León 64710Mexico. Department of Breast Surgery Center Hospital Zambrano HellionTecnológico de MonterreyNuevo León 66260Mexico

BACKgRoUND Fibroadenoma(FA)is the most common tumor found in young women,although it can occur in any age group.Ductal carcinoma in situ(DCIS)that is confined in a FA is rare;it is most frequently reported as an incidental finding.CASE SUMMARY We report a case of DCIS within a FA in a 46-year-old female without cancerrelated personal and family histories.The patient was diagnosed with a breast conglomerate of nodules and was followed for 1 year.In the current control image study,we found suspicious microcalcification,as a new finding,within one of the nodules.Consequently,a core biopsy of the tumor,which appeared hypoechoic,oval,and circumscribed,was performed.The pathological diagnosis was ductal carcinoma in situ within a fibroepithelial lesion.The patient underwent breastconserving surgery and received radiotherapy as well as endocrine therapy(tamoxifen).CoNCLUSIoN We recommend a multidisciplinary approach for adequate treatment and followup.

关键词： Carcinoma in situ Fibroadenoma Mammography Ultrasound Magnetic resonance imaging Radiology Case report

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Spark Plasma Sintering of Boron Carbide Using Ti_(3)SiC_(2) as a Sintering Additive

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 645-650页

作者： Hülya Biçer Mustafa Tuncer Hasan göçmez Iurii Bogomol valerii Kolesnichenko Andrey Ragulya Kutahya Dumlupinar University School of EngineeringDepartment of Metallurgical and Materials EngineeringKütahya 43100Tur-key Boron Based Advanced Ceramics Application and Research Center Kütahya Dumlupınar UniversityKütahya 43100Turkey Advanced Technologies Center(İLTEM) Kütahya Dumlupınar UniversityKütahya 43000Turkey Department of High-Temperature Ma-terials and Powder Metallurgy National Technical University of Ukraine“Igor Sikorsky Kyiv Polytechnic Institute”Kyiv 03056Ukraine Frantsevich Institute for Problems of Materials Science National Academy of Sciences of UkraineKyiv 03056Ukraine

Boron carbide has unique properties for wide application possibilities;however,poor sinterability limits its applications.one approach to overcome this limitation is the addition of secondary phases into boron carbide.Boron carbide based composite ceramics are produced by the direct addition of secondary phases into the structure or via reactive sintering using a sintering additive.The present study investigated the effect of Ti_(3)SiC_(2) addition to boron carbide by reactive spark plasma sintering in the range of 1700-1900℃.Ti_(3)SiC_(2) phase decomposed at high temperatures and reacted with B4C to form secondary phases of TiB2 and SiC.The results demonstrated that the increase of Ti_(3)SiC_(2) addition(up to 15 vol%)effectively promoted the densification of B4C and yielded higher hardness.However,as the amount of Ti_(3)SiC_(2) increased further,the formation of microstructural inhomogeneity and agglomeration of secondary phases caused a decrease in hardness.

关键词： reactive sintering SPS boron carbide MAX phase

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Digital Social Connectedness as a Lifeline for older People: Use and Non-use of vinclesBCN During the Pandemic

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International Journal of Disaster Risk Science 2024年第2期15卷 251-264页

作者： Israel Rodríguez-giralt Daniel López-gómez Roser Beneito-Montagut CareNet IN3 Universitat Oberta de Catalunya School of Social Sciences Cardiff University

This article presents the results of a study that evaluated vinclesBCN during CovID-19. This digital-based public social service aims to prevent loneliness and isolation in +65-year-old adults living in Barcelona. Through service user(N = 12) and professional(N = 6) interviews and a questionnaire with service users(N = 255), we demonstrate the pivotal role of digital connectedness in transforming vinclesBCN into a lifeline during the pandemic. The analysis revealed the importance of sociability, social support, and, especially, entertainment in coping with pandemic fatigue and facilitating social connectivity and support among users. Users engaged in activities such as sharing images, songs, memes, and daily greetings to provide proximity, sociability, and care among users, whether they belonged to preexisting groups or were newly introduced to the platform. It also facilitated the identification of individuals who needed companionship, comfort, or more specialized support. The findings emphasize the significance of entertainment as a resilience-building strategy during times of uncertainty. Despite the positive impact, not all users equally used the platform. Non-use was strongly associated with being a woman, having a low educational level, having preexisting social relationships, less time of enrolment in the platform, as well as a high perception of loneliness, poor self-reported health, and low mood. The article underscores the need for further research into older adults' digital engagement during crises, its role in building resilience, and advocating for inclusive digital interventions that take into account diverse older adults' needs and experiences in crisis contexts.

关键词： Barcelona CovID-19 pandemic Digital social connectedness Entertainment older adult resilience Public digital service

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