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Observation about the Classical Electromagnetic Gauge Transformation and Its Quantum Correspondence

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Journal of Modern Physics 2024年第4期15卷 474-479页

作者： Gustavo V. l.pez Jorge A. lizarraga Departamento de Física Universidad de Guadalajara Guadalajara Mexico

Using the landau and symmetric gauges for the vector potential of a constant magnetic field and the quantum problem of a charged particle moving on a flat surface, we show the classical electromagnetic gauge transformation does not correspond to a one-dimensional unitary group transformation U(1) of the wave function for the quantum case. In addition, with the re-examination of the relation between the magnetic field B and its vector potential A, we found that, in order to have a consistent formulation of the dynamics of the charged particle with both expressions, we must have that B=∇×A if and only if B≠0.

关键词： Gauge Transformation Harmonic Oscillator Quantum Hall Effect Electromagnetic Potentials

Electrifying Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ) for focalized heating in oxygen transport membranes

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Journal of Energy Chemistry 2024年第4期91卷 99-110页

作者： Marwan laqdiem Julio García-Fayos laura Almar Alfonso J.Carrillo Álvaro Represa JoséM.l.pez Nieto Sonia Escolástico David Catalán-Martinez Jose M.Serra Instituto de Tecnología Química(Universitat Politècnica de València–Consejo Superior de Investigaciones Científicas) Av.Los Naranjos s/nE-46022 ValenciaSpain

Industry decarbonization requires the development of highly efficient and flexible technologies relying on renewable energy resources,especially biomass and solar/wind *** the case of pure oxygen production,oxygen transport membranes(OTMs)appear as an alternative technology for the cryogenic distillation of air,the industrially-established process of producing ***,OTMs could provide oxygen from different sources(air,water,CO_(2),etc.),and they are more flexible in adapting to current processes,producing oxygen at 700^(-1)000℃.Furthermore,OTMs can be integrated into catalytic membrane reactors,providing new pathways for different *** first part of this study was focused on electrification on a traditional OTM material(Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)),imposing different electric currents/voltages along a capillary *** to the emerging Joule effect,the membrane-surface temperature and the associated O_(2) permeation flux could be ***,the OTM is electrically and locally heated and reaches 900℃on the surface,whereas the surrounding of the membrane was maintained at 650℃.The O_(2)permeation flux reached for the electrified membranes was~3.7 Nml min^(-1)cm^(-2),corresponding to the flux obtained with an OTM non-electrified at 900℃.The influence of depositing a porous Ce_(0.8)Tb_(0.2)O_(2-δ) catalytic/protective layer on the outer membrane surface revealed that lower surface temperatures(830℃)were detected at the same imposed electric ***,the electrification concept was demonstrated in a catalytic membrane reactor(CMR)where the oxidative dehydrogenation of ethane(ODHE)was carried *** reaction is very sensitive to temperature,and here,we demonstrate an improvement of the ethylene yield by reaching moderate temperatures in the reaction chamber while the O_(2) injection into the reaction can be easily fine-tuned.

关键词： Oxygen permeation Oxidative dehydrogenation of ethane Oxygen transport membranes Joule effect Mixed ionic-electronic conductors Catalytic membrane reactors

Twenty years of population dynamics in European beech-oak forest at their rear range margin anticipate changes in its structure and composition

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Forest Ecosystems 2024年第3期11卷 358-370页

作者： álvaro Rubio-Cuadrado Iciar Alberdi Isabel Canellas Fernando Montes Jesús Rodríguez-Calcerrada Rosana l.pez Guillermo G.Gordaliza María Valbuena-Carabana Nikos Nanos Ramón Perea luis Gil Departamento de dinamica y gestion forestal Instituto de Ciencias Forestales(ICIFOR-INIA)CSICCtra.La Coruna km 7.528040MadridSpain Departamento de Sistemas y Recursos Naturales Escuela Tecnica Superior de Ingeniería de MontesForestal y del Medio NaturalUniversidad Politecnica de Madrid.Ciudad Universitaria s/n28040MadridSpain School of Forestry and Natural Environment Aristotle University of ThessalonikiUniversity Campus54124ThessalonikiGreece

There is an increasing interest in restoring degraded forests,which occupy half of the forest *** the forms of restoration,passive restoration,which involves the elimination of degrading factors and the free evolution of natural dynamics by applying minimal or no management,is gaining *** dynamics is difficult to predict due to the influence of multiple interacting factors such as climatic and edaphic conditions,composition and abundance of species,and the successional character of these ***,we study the natural dynamics of a mixed forest located in central Spain,which maintained an open forest structure,due to intensive use,until grazing and cutting were banned in the *** most frequent woody species in this forest are Fagus sylvatica,Quercus petraea,Quercus pyrenaica,Ilex aquifolium,Sorbus aucuparia,Sorbus aria and Prunus avium,with contrasting shade and drought *** species are common in temperate European deciduous forest and are found here near their southern distribution limit,except for *** order to analyze forest dynamics and composition,three inventories were carried out in 1994,2005 and *** results show that,despite the Mediterranean influence,the natural dynamics of this forest has been mainly determined by different levels of shade *** the abandonment of grazing and cutting,*** expanded rapidly due to its lower shade tolerance,whereas after canopy closure and forest densification,shade-tolerant species gained ground,particularly ***,despite its lower drought and late-frost *** the current dynamics continue,*** will overtake the rest of the species,which will be relegated to sites with shallow soils and steep ***,all the multi-centennial beech trees,which are undergoing a rapid mortality and decline process,will disappear.

关键词： Forest succession Secondary forest Woodland Mixed forest Competition Recruitment

The relationship between DNA fragmentation and the intensity of morphologically abnormal human spermatozoa

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Asian pacific Journal of Reproduction 2024年第1期13卷 22-27页

作者： Mercedes González-Martínez Pascual Sánchez-Martín Carmen l.pez-Fernández Stephen D.Johnston Jaime Gosálvez Clínica Ginemed Unidad de ReproducciónSevillaSpain Department of Biology Universidad Autónoma de MadridCantoblancoMadridSpain School of Environment The University of QueenslandGattonAustralia School of Veterinary Science The University of QueenslandGattonAustralia

Objective:To determine the relationship between teratozoospermia and sperm DNA fragmentation(SDF)in the human ***:This retrospective study included 100 normozoospermic men as a control cohort(abnormal forms>14%),210 patients with a high level of abnormal forms(≤4%)and 65 patients presenting with a moderate level of abnormal forms(>4%to≤14%)based on the World Health Organization *** morphology was assessed using bright field *** DNA fragmentation was assessed using the sperm chromatin dispersion ***-parametric analyses were conducted to examine the relationship between abnormal sperm morphology and sperm DNA fragmentation;receiver operating characteristic(ROC)analyses were conducted to assess sensitivity and specificity of this ***:A correlation analysis revealed that the higher the proportion of abnormal spermatozoa in the ejaculate,the higher the level of SDF(Spearman's Rho=-0.230;Pll cohorts were compared(Plso retained when the different cohorts were compared *** analysis showed a moderate but significant predictive value for SDF to differentiate patients with different levels of ***:Although analysis of a more continuous range of values for teratozoospermia would help further clarify any causal relationship with SDF,there is clearly a synergistic or coincident affiliation between these variables that needs to be acknowledged by the clinician when interpreting the spermiogram.

关键词： Teratozoospermia Sperm morphology Sperm DNA fragmentation Male factor Human reproduction Human fertility

Evaluation of Clinical Characteristics and Plasma Cortisol Concentrations in Individuals with COVID-19 and Post-COVID Syndrome

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Case Reports in Clinical Medicine 2024年第1期13卷 12-24页

作者： David Alejandro García l.pez Stephania Ramos Hernández Yamile l.pez-Hernández María Argelia l.pez luna Elena Donaji Ramírez Alvarado Rosa María Ramírez Santoyo Sergio Hugo Sánchez Rodríguez laboratorio de Biología Celular y Neurobiología Universidad Autónoma de Zacatecas México Zacatecas Unidad Académica de Ciencias Químicas Universidad Autónoma de Zacatecas México Zacatecas laboratorio de Metabolómica y Proteómica Universidad Autónoma de Zacatecas México Zacatecas laboratorio de Bacterias y Hongos filamentosos Universidad Autónoma de Zacatecas México Zacatecas

COVID-19 generates systematic alterations in humans both in active stages of infection and over time, called post-COVID syndrome. Cortisol is a hormone that is overexpressed in inflammation and cellular stress processes. Its main function is to return to physiological homeostasis, so its evaluation together with other clinical parameters can allow us to determine the degree of systemic affectation by COVID-19. Objective: To evaluate changes in clinical parameters and plasma cortisol concentrations in patients with active COVID-19 and post-COVID syndrome. Material and Methods: Healthy patients, in stages of mild infection, critical and with post-COVID syndrome, were recruited, obtaining, through clinical diagnoses and interviews, their main clinical characteristics, in addition to plasma, in which cortisol concentrations were determined using competitive ElISA. Results: The critical stage group had higher frequencies of comorbidities, clinical symptoms, as well as more altered laboratory parameters compared to the other subgroups. In the post-COVID syndrome group after the initial infection, most laboratory parameters recovered, however, several clinical symptoms remained latent over time. The determination of cortisol showed an increase in its concentration, being higher in patients in critical stage and with post-COVID syndrome. Conclusion: COVID-19 disease generates clinical alterations that trigger an increase in plasma cortisol. These alterations increase as the stages of infection become more severe and some of them remain altered in patients with post-COVID syndrome.

关键词： COVID-19 Cortisol Post-COVID Syndrome

Increased CO2 levels during the First Half of Incubation at High Altitude Modifies Embryonic Development of Fertile leghorn Breeder Eggs

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Food and Nutrition Sciences 2024年第7期15卷 524-547页

作者： Marco A. Juárez-Estrada Erik I. l.pez-Ruiz Sonia l.pez-Cordova Guillermo Tellez-Isaias Omar F. Prado-Rebolledo Departamento de Medicina y Zootecnia de Aves Facultad de Medicina Veterinaria y Zootecnia Universidad Nacional Autnoma de Mxico Ciudad de Mxico Mxico Department of Poultry Science Division of Agriculture University of Arkansas Fayetteville USA Facultad de Medicina Veterinaria y Zootecnia Universidad de Colima Tecomn Mxico

The exchange of oxygen (O2) and carbon dioxide (CO2) within an incubator has a significant impact on embryonic development (ED) and hatching processes. This study examines the influence of non-ventilation (NV) conditions during the first ten days of incubation at high altitudes on leghorn hens hatching eggs. Five hundred four hatching eggs were equally divided into three treatment groups and placed in twelve incubators (R = 4). The first group was subjected to standard ventilated conditions (V) during the setting phase. The ventilation inlet holes of the remaining incubators in the NV treatments were closed with either micropore (M) or polypropylene (P) tape, referred to as NVM and NVP groups, respectively. These two different airtight settings were intended to allow for a gradual rise in CO2 naturally generated by the embryos. Results indicate that carbon dioxide concentration gradually increased during the first half of incubation, reaching 1.42% in the NVM group and 1.20% in the NVP group, while the V condition group remained at 0.15%. From 10 days of incubation onwards, normal V conditions were restored in all incubators. The highest hatchability of fertile eggs (HFE) was shown by the NVP group (55.7%), followed by the V (52.6%) and NVM (38.6%) groups. The NVP group showed a greater yolk-free body mass (YFBM) from 10 days of incubation until the hatch basket transfer. NV conditions during the first 10 days of incubation at high altitude produced higher YFBM with gradually decreasing yolk sac mass. In comparison to the NVM and V conditions, the particular NVP condition showed a beneficial impact on the quality of hatched chicks. Sustaining NVP condition (1.2% of CO2) throughout the first half of incubation at high altitude generated the optimal environment in the incubator ensuring the best hatchability results. This study highlights how important it is for hatchery managers to recognize the influence of low O2 and high levels of CO2 on the development trajectori

关键词： Non-Ventilation Hypercapnia Hypoxia Egg Mass loss Hatchability Embryonic Mortality Hatchling Chick Quality

Neuroprotective effects of G9a inhibition through modulation of peroxisome-proliferator activator receptor gamma-dependent pathways by miR-128

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Neural Regeneration Research 2024年第11期19卷 2532-2542页

作者： Aina Bellver-Sanchis Pedro AAvila-l.pez Iva Tic David Valle-García Marta Ribalta-Vilella luis labrador Deb Ranjan Banerjee Ana Guerrero Gemma Casadesus Coralie Poulard Mercè Pallàs Christian Grinán-Ferré Department of Pharmacology and Therapeutic Chemistry Institut de Neurociències-Universitat de BarcelonaBarcelonaSpain Department of Biochemistry and Molecular Genetics Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Institute of Biotechnology National Autonomous University of MexicoCuernavacaMexico Department of Pharmacology and Therapeutics Health Science Center-University of FloridaGainesvilleFLUSA Department of Chemistry National Institute of Technology DurgapurM G AvenueDurgapurWest BengalIndia Cancer Research Cancer lyon Universitéde LyonLyonFrance Inserm U1052 Centre de Recherche en Cancérologie de LyonLyonFrance CNRS UMR5286 Centre de Recherche en Cancérlogie de LyonLyonFrance Centro de Investigación en Red Enfermedades Neurodegenerativas(CIBERNED)Instituto de Salud Carlos IIIMadridSpain Neuroimmunology Department National Institute of Neurology and Neurosurgery“Manuel Velasco Suárez”Mexico CityMexico

Dysregulation of G9a,a histone-lysine N-methyltransferase,has been observed in Alzheimer’s disease and has been correlated with increased levels of chronic inflammation and oxidative ***,microRNAs are involved in many biological processes and diseases playing a key role in pathogenesis,especially in multifactorial diseases such as Alzheimer’s ***,our aim has been to provide partial insights into the interconnection between G9a,microRNAs,oxidative stress,and *** better understand the biology of G9a,we compared the global microRNA expression between senescence-accelerated mouse-prone 8(SAMP8)control mice and SAMP8 treated with G9a inhibitor *** found a downregulation of miR-128 after a G9a inhibition treatment,which interestingly binds to the 3′untranslated region(3′-UTR)of peroxisome-proliferator activator receptor γ(PPARG)***,Pparg gene expression levels were higher in the SAMP8 group treated with G9a inhibitor than in the SAMP8 control *** also observed modulation of oxidative stress responses might be mainly driven Pparg after G9a *** confirm these antioxidant effects,we treated primary neuron cell cultures with hydrogen peroxide as an oxidative *** this setting,treatment with G9a inhibitor increases both cell survival and antioxidant ***,up-regulation of PPARγby G9a inhibitor could also increase the expression of genes involved in DNA damage responses and *** addition,we also described that the PPARγ/AMPK axis partially explains the regulation of autophagy markers ***,PPARγ/GADD45αpotentially contributes to enhancing synaptic plasticity and neurogenesis after G9a ***,we propose that pharmacological inhibition of G9a leads to a neuroprotective effect that could be due,at least in part,by the modulation of PPARγ-dependent pathways by miR-128.

关键词： aging cognitive decline epigenetics G9a inhibition microRNAs miR-128 peroxisome-proliferator activator receptorγ(PPARγ) PPARG SAMP8

Mental health in the virtual world:Challenges and opportunities in the metaverse era

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World Journal of Clinical Cases 2024年第17期12卷 2939-2945页

作者： Yolanda l.pez del Hoyo Matilde Elices Javier Garcia-Campayo Department of Psychology and Sociology University of ZaragozaZaragoza 50009Spain Mental Health Research Group Hospital del Mar Medical Research InstituteBarcelona 08003Spain Department of Psychiatry Miguel Servet HospitalAragon Institute for Health ResearchUniversity of ZaragozaZaragoza 50009Spain

Current rates of mental illness are *** illness mainly affects females and younger age *** use of the internet to deliver mental health care has been growing since 2020 and includes the implementation of novel mental health treatments using virtual reality,augmented reality,and artificial intelligence.A new three dimensional digital environment,known as the metaverse,has emerged as the next version of the *** intelligence,augmented reality,and virtual reality will create fully immersive,experiential,and interactive online environments in the *** will use a unique avatar to do anything they do in their“real”lives,including seeking and receiving mental health *** this opinion review,we reflect on how the metaverse could reshape how we deliver mental health treatment,its opportunities,and its challenges.

关键词： Metaverse Virtual world Artificial intelligence Mental health Virtual reality Augmented reality Technology

Metastatic pancreatic and lung cancer patient in complete remission following immunotherapy: A case report and review of literature

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2233-2240页

作者： Joaquina Martínez-Galán Cristina Jiménez-luna Isabel Rodriguez Elisabeth Maza Carlos García-Collado Antonio Rodríguez-Fernández Javier luis l.pez-Hidalgo Octavio Caba Department of Medical Oncology Virgen de las Nieves University HospitalGranada 18014Spain Instituto de Investigación Biosanitaria Ibs.GranadaGranada 18012Spain Institute of Biopathology and Regenerative Medicine(IBIMER) University of GranadaGranada 18016Spain Pharmacogenetics Unit Virgen de las Nieves University HospitalGranada 18014Spain Department of Medicina Nuclear Virgen de las Nieves University HospitalGranada 18014Spain Department of Anatomía Patológica Virgen de las Nieves University HospitalGranada 18014Spain

BACKGROUND Metastatic pancreatic ductal adenocarcinoma(PDAC)is a lethal malignancy with dispiriting survival *** is a promising approach to many cancer types,but achieves poor outcomes in advanced PDAC due to its immunosuppressive tumor *** describe a case of metastatic PDAC effectively treated with *** SUMMARY We report the case of a 67-year-old woman with unresectable locally advanced PDAC,treated with gemcitabine plus nab-paclitaxel followed by radiotherapy plus *** nine months,pancreatic tumor progression was observed at the level of the hepatic hilum with the appearance of a new pulmonary nodule suggestive of a second primary,confirmed by left lung *** immunotherapy was then initiated with pembrolizumab,an immune checkpoint inhibitor targeting programmed cell death protein-1 that covers the two tumor *** patient showed a complete metabolic response that was maintained throughout the *** patient continues to be disease-free at 5.6 years since the start of *** These results suggest that the administration of pembrolizumab after chemoradiotherapy has a beneficial effect in patients with metastatic *** our knowledge,this is the first reported case of a patient with metastatic PDAC and metastatic lung cancer showing such a long-lasting complete response after pembrolizumab treatment without curative *** studies are required to determine biomarkers that identify PDAC patients most likely to benefit from this immunotherapy.

关键词： Pancreatic ductal adenocarcinoma lung cancer Immunotherapy Pembrolizumab Programmed cell death protein-1 Case report