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Cutaneous Dengue Virus Inoculation Triggers Strong B Cell Reactions but Contrastingly Poor T Cell Responses

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Virologica Sinica 2020年第5期35卷 575-587页

作者： Edith Marcial-Juárez Julio garcía-Cordero Raúl antonio Maqueda-Alfaro Rafael Eduardo Saucedo-López Luvia Enid Sánchez-Torres Leticia Cedillo-Barrón Leopoldo Flores-Romo Department of Cell Biology Center for Advanced Research(CINVESTAV-IPN)The National Polytechnic Institute07360 Mexico CityMexico Department of Molecular Biomedicine Center for Advanced Research(CINVESTAV-IPN)The National Polytechnic Institute07360 Mexico CityMexico Immunology Department The National School of Biological Sciences(ENCB-IPN)The National Polytechnic Institute11340 Mexico CityMexico

Dengue is a global health problem without current specific treatment nor safe vaccines *** severe dengue is related to pre-existing non-neutralizing dengue virus(DENV)antibodies,the role of T cells in protection or pathology is *** cutaneous DENV infection in immunocompetent mice we previously showed the generation of PNA+germinal centers(GCs),now we assessed the activation and proliferation of B and T cells in draining lymph nodes(DLNs).We found a drastic remodelling of DLN compartments from 7 to 14 days post-infection(dpi)with greatly enlarged B cell follicles,occupying almost half of the DLN area compared to*24%in na?ve *** clusters of proliferating(Ki-67+)cells inside B follicles were found 14 dpi,representing*33%of B cells in DLNs but only*2%in noninfected *** GCs,we noticed an important recruitment of tingle body macrophages removing apoptotic *** contrast,the percentage of paracortex area and total T cells decreased by 14–16 dpi,compared to *** randomly distributed Ki-67+T cells were found,similar to non-infected ***69 expression by CD4+and CD8+T cells was minor,while it was remarkable in B cells,representing 1764.7%of change from basal levels 3 *** apparent lack of T cell responses cannot be attributed to apoptosis since no significant differences were observed compared to noninfected *** study shows massive B cell activation and proliferation in DLNs upon DENV *** contrast,we found very poor,almost absent CD4+and CD8+T cell responses.

关键词： Dengue virus(DENV) B and T cells proliferation Lymphocyte activation Lymph nodes In vivo cutaneous infection Immunocompetent mice

Alpha2-adrenergic receptor activation reinstates motor deficits in rats recovering from cortical injury

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Neural Regeneration Research 2023年第4期18卷 875-880页

作者： Gabriela garcía-Díaz Laura ERamos-Languren Carmen Parra-Cid Joel Lomelí Sergio Montes Camilo Ríos antonio Bueno-Nava Ignacio Valencia-Hernández Rigoberto González-Piña Department of Pharmacology Section of Postgraduate Studies and ResearchHigh Medical SchoolInstituto Politécnico NacionalSalvador Díaz MirónAlcaldía Miguel HidalgoMexico CityMexico Department of Neurobiology of Aging and Brain Damage Coordination of Psychobiology and NeurosciencesFaculty of PsychologyNational Autonomous University of MexicoAv.Universidad 3040Col.Copilco UniversidadAlcaldía CoyoacánMexico CityMexico Direction of Research National Institute of Rehabilitation LGIICalz.Mexico-Xochimilco 289Col.Arenal de GuadalupeAlcaldía TlalpanMexico CityMexico Department of Pharmacology Multidisciplinary Academic Unit Reynosa-Aztlan ReynosaAutonomous University of Tamaulipascalle 16 y lago de ChapalaCol.AztlánTamaulipasMexico Department of Neurochemistry National Institute of Neurology and Neurosurgery MVSAv.Insurgentes Sur 3877Col.La FamaAlcaldia TlalpanMexico CityMexico Department of Special Education University of the AmericasPuebla 223Col.RomaAlcaldía CuauhtémocMexico CityMexico

Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous *** of norepinephrine release by clonidine is correlated with motor deficits after motor cortex *** aim of this study was to analyze the role ofα-adrenergic receptors in the restoration of motor deficits in recovering rats after brain *** rats were randomly assigned to the sham and injury groups and then treated with the following pharmacological agents at 3 hours before and 8 hours,3 days,and 20 days after ferrous chloride-induced cortical injury:saline,clonidine,efaroxan(a selective antagonist ofα-adrenergic receptors)and clonidine+*** sensorimotor score,the immunohistochemical staining forα-adrenergic receptors,and norepinephrine levels were *** hours post-injury,the sensorimotor score and norepinephrine levels in the locus coeruleus of the injured rats decreased,and these effects were maintained 3 days ***,20 days later,clonidine administration diminished norepinephrine levels in the pons compared with the sham *** effect was accompanied by sensorimotor *** effects were blocked by *** conclusion,an increase inα-adrenergic receptor levels was observed after *** restores motor deficits in rats recovering from cortical injury,an effect that was prevented by *** underlying mechanisms involve the stimulation of hypersensitiveα-adrenergic receptors and inhibition of norepinephrine activity in the locus *** results of this study suggest thatαreceptor agonists might restore deficits or impede rehabilitation in patients with brain injury,and therefore pharmacological therapies need to be prescribed cautiously to these patients.

关键词： alpha2-adrenoceptors ambulatory behavior clonidine cortical injury efaroxan functional recovery immunohistochemistry motor deficit norepinephrine sensorimotor score

Litter production and leaf nutrient concentration and remobilization in response to climate seasonality in the central Amazon

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Journal of Forestry Research 2024年第3期35卷 131-141页

作者： Ricardo antonio Marenco Saul Alfredo Antezana-Vera Daniela Pereira Dias Luiz antonio Candido Instituto Nacional de Pesquisas da Amazonia Coordenagao de Uso da Terra e Mudanca ClimaticaAv.Andre Araujo 2936ManausAM69067-375Brazil Programa de pos-Graduagao em Agricultura no Tropico Umido Instituto Nacional de Pesquisas da Amazonia-INPAManausAMBrazil Unidade Academica de Ciencias Agrarias Universidade Federal de JataiBR 364km 195JataiGO 75801-615Brazil

Litterfall is the largest source of nutrients to for-est soils of tropical ***,variability in lit-terfall production,nutrient remobilization,and changes in leaf nutrient concentration with climate seasonality remain largely unknown for the central *** study meas-ured litterfall production,leaf nutrient remobilization,and leaf area index on a forest plateau in the central *** was measured at monthly intervals during 2014,while nitrogen,phosphorus,potassium,calcium and mag-nesium concentrations of leaf litter and canopy leaves were measured in the dry and rainy seasons,and remobilization rates *** area index was also recorded in the dry and rainy *** litterfall varied from 33.2(in the rainy season)to 87.6 g m^(-2) in the dry season,while leaf area index increased slightly in the rainy *** seasonality had no effect on concentrations of nitrogen,calcium,and magnesium,whereas phosphorous and potassium responded to rainfall seasonality *** phosphorous increased,potassium decreased during the dry *** seasons,nitrogen,potassium,and phosphorous decreased in leaf litter;calcium increased in leaf litter,while magnesium remained unaffected with leaf ***,the five nutrients had similar remobilization rates over the *** absence of climate seasonality on nutrient remobilization suggests that the current length of the dry season does not alter nutrient remobilization rates but this may change as dry periods become more prolonged in the future due to climate change.

关键词： Throughfall Nutrient cycling Climatic seasonality Leaf mass per area

Seismic performance of a reinforced concrete building retrofitted with self-centering shape memory alloy braces

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Earthquake Engineering and Engineering Vibration 2022年第3期21卷 785-809页

作者： Massimiliano Ferraioli antonio Concilio Carmine Molitierno Department of Engineering University of Campania“Luigi Vanvitelli”via Roma 2981031 Aversa(CE)Italy Adaptive Structures Div. the Italian Aerospace Research Centre(CIRA)via Maiorise81043 Capua(CE)Italy Department of Structures for Engineering and Architecture University of Naples“Federico Ⅱ”via Claudio 2180125NapoliItaly

Self-centering earthquake-resistant structures have received increased attention due to their ability to reduce post-earthquake residual deformations and,thus,repair time and *** stimulated the development of recentering shape memory alloy(SMA)dampers that use superelastic nitinol wires to dissipate energy and self-center the ***,there are still a few case studies applications on full-scale RC buildings in the ***,general guidelines or even simplified approaches for the practical design of SMA damped braces are still *** paper focuses on evaluating the effect of using self-centering shape memory alloy dampers for buckling-restrained braces applied for the seismic retrofit of a complex RC building structure.A design method originally proposed for elastoplastic dampers was implemented to size the SMA dampers to be placed on selected spans and stories of a *** effectiveness of the design procedure was demonstrated by nonlinear time-history analyses under different sets of earthquake strong ground *** analysis results show that the recentering shape memory alloy bracing system is effective in limiting the maximum transient inter-story drifts and reducing the residual inter-story drifts after strong seismic events,due to its excellent recentering behavior together with its not negligible energy dissipation capacity.

关键词： RC buildings seismic retrofit buckling-restrained braces shape memory alloys dampers self-centering

Surrogacy in Reproductive Medicine: Ethical and Legal Analysis of the Procedure

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Journal of Biosciences and Medicines 2016年第6期4卷 46-51页

作者： José antonio garcía Pereañez Astrid Elena Lince Echavarría Medicine Faculty Universidad de Antioquia American University Corporation Medellin Colombia Medicine Faculty Universidad de Antioquia Legal Office of the American University Corporation Medellin Colombia

This text sets out the different arguments regarding surrogacy as a reproductive medicine tech-nique in Colombia. The procedure is described, as well as the legal matters that this issue generates. Gestational carriers appear as an alternative for couples who want to have a child but they are not able to conceive because of infertility issues and do not want to go through an adoption process. Therefore, they adhere to surrogacy as an alternative of assisted human reproduction;a procedure that in Colombia faces serious legal gaps and causes ethical dilemmas in the collective imagery. These situations suggest an open discussion through a dialectics between the scientific progress advances, the lack of legal regulation and the constants against ethical positions that the surrogacy procedure causes in Colombia and other parts of the world.

关键词： Reproductive Medicine Gestational Carrier Ethics Legal Colombia

Ligninolytic Peroxidase-Like Activity of a Synthetic Metalloporphine Immobilized onto Mercapto-Grafted Crosslinked PVA Inspired by the Active Site of Cytochrome P450

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催化学报 2011年第11期32卷 1663-1666页

作者： Paolo ZUCCA antonio RESCIGNO Enrico SANJUST Dipartimento di Scienze e Tecnologie Biomediche Università di Cagliari Monserrato 09042 Italy Consorzio per lo Sviluppo dei Sistemi a Grande Interfase Sesto Fiorentino 50019 Italy

A synthetic metalloporphine was immobilized onto a PVA-based and mercapto-grafted solid support, emulating the active site of cytochrome P450. Its ligninolytic peroxidase-like catalytic activity was studied. The coordinated mercapto ligand significantly affected the catalytic features of the catalyst because the oxidation of lignin-model compounds was very slow by comparison with imidazoleand pyridine-coordinated immobilized metalloporphines. Conversely, the catalyst efficiently bleached several industrial dyes and thus demonstrated promising activity for this application. Based on this altered substrate specificity the oxygen-donor catalytic route seems to be more favorable than a single electron oxidation pathway.

关键词： porphine porphyrin lignin peroxidase cytochrome P450 biomimetic

Mechanics of tubular helical assemblies:ensemble response to axial compression and extension

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Acta Mechanica Sinica 2021年第2期37卷 173-186页

作者： Jacopo Quaglierini Alessandro Lucantonio antonio DeSimone Department of Excellence in Robotics and AI The BioRobotics InstituteScuola Superiore Sant'Anna56127 PisaItaly SISSA-Scuola Intemazionale Superiore di Studi Avanzati 34136 TriesteItaly

Nature and technology often adopt structures that can be described as tubular helical ***,the role and mechanisms of these structures remain *** this paper,we study the mechanical response under compression and extension of a tubular assembly composed of 8 helical Kirchholf rods,arranged in pairs with opposite chirality and connected by pin joints,both analytically and *** first focus on compression and find that,whereas a single helical rod would buckle,the rods of the assembly deform coherently as stable helical shapes wound around a common ***,we investigate the response of the assembly under different boundary conditions,highlighting the emergence of a central region where rods remain circular ***,we study the effects of different hypotheses on the elastic properties of rods,i.e.,stress-free rods when straight versus when circular helices,Kirchhoff’s rod model versus Sadowsky’s ribbon *** up,our findings highlight the key role of mutual interactions in generating a stable ensemble response that preserves the helical shape of the individual rods,as well as some interesting features,and they shed some light on the reasons why helical shapes in tubular assemblies are so common and persistent in nature and technology.

关键词： Computational mechanics Helical assemblies Kirchhoff rod Sadowsky ribbon Ensemble response

Exploring seven hundred years of transhumance, climate dynamic, fire and human activity through a historical mountain pass in central Spain

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Journal of Mountain Science 2016年第7期13卷 1139-1153页

作者： José antonio LóPEZ-SáEZ Francisca ALBA-SáNCHEZ Sandra ROBLES-LóPEZ Sebastián PéREZ-DíAZ Daniel ABEL-SCHAAD Silvia SABARIEGO-ruiz Arthur GLAIS Research Group Archaeobiology Institute of History CSIC Dept.Botany Faculty of Sciences University of Granada Dept.of Plant Biology Faculty of Biology Complutense University LETG CAEN GEOPHEN-UMR 6554 CNRS University of Caen-Normandie

A high-altitude peat sequence from the heart of the Spanish Central System(Gredos range) was analysed through a multi-proxy approach to determine the sensitivity of high-mountain habitats to climate, fire and land use changes during the last seven hundred years, providing valuable insight into our understanding of the vegetation history and environmental changes in a mountain pass close to a traditional route of transhumance. The pollen data indicate that the vegetation was dominated by shrublands and grasslands with scattered pines in high-mountain areas, while in the valleys cereals, chestnut and olive trees were cultivated. Strong declines of high-mountain pines percentages are recorded at 1540, 1675, 1765, 1835 and 1925 cal AD, which may be related to increasing grazing activities and/or the occurrence of anthropogenic fires. The practice of mountain summer farming and transhumance deeply changed and redesigned the landscape of the high altitudes in central Spain(Gredos range) since the Middle Ages, although its dynamics was influenced in some way by climate variability of the past seven centuries.

关键词： Climate and human impacts Fire Late Holocene Gredos range Vegetation history

Hybrid first and second order attention Unet for building segmentation in remote sensing images

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Science China(Information Sciences) 2020年第4期63卷 69-80页

作者： Nanjun HE Leyuan FANG antonio PLAZA College of Electrical and Information Engineering Hunan University Hyperspectral Computing Laboratory Department of Technology of Computers and CommunicationsEscuela Politecnica University of Extremadura

Recently, building segmentation(BS) has drawn significant attention in remote sensing applications. Convolutional neural networks(CNNs) have become the mainstream analysis approach in this field owing to their powerful representative ability. However, owing to the variation in building appearance, designing an effective CNN architecture for BS still remains a challenging task. Most of CNN-based BS methods mainly focus on deep or wide network architectures, neglecting the correlation among intermediate *** address this problem, in this paper we propose a hybrid first and second order attention network(HFSA)that explores both the global mean and the inner-product among different channels to adaptively rescale intermediate features. As a result, the HFSA can not only make full use of first order feature statistics, but also incorporate the second order feature statistics, which leads to more representative feature. We conduct a series of comprehensive experiments on three widely used aerial building segmentation data sets and one satellite building segmentation data set. The experimental results show that our newly developed model achieves better segmentation performance over state-of-the-art models in terms of both quantitative and qualitative results.

关键词： building segmentation(BS) convolutional neural networks(CNNs) remote sensing high order pooling attention