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phosphatase and tensin homolog is a differential diagnostic marker between nonalcoholic and alcoholic fatty liver disease

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World Journal of Gastroenterology 2016年第14期22卷 3735-3745页

作者： Andrea sanchez-Pareja Sophie clément Marion Peyrou Laurent Spahr Francesco Negro Laura Rubbia-Brandt Michelangelo Foti Division of clinical Pathology University Hospital of Geneva Department of Cellular Physiology and Metabolism Faculty of Medicine University of Geneva Diabetes Center Faculty of Medicine University of Geneva Division of Gastroenterology and Hepatology University Hospital of Geneva

AIM: To investigate the protein expression of phosphatase and tensin homolog (PTEN) in human liver biopsies of patients with alcoholic and non-alcoholic liver ***: PTEN protein expression was assessed by immunohistochemistry in formalin-fixed, paraffin-embedded liver sections of patients with non-alcoholic fatty liver disease (NAFLD) (n = 44) or alcoholic liver disease (ALD) (n = 25). Liver resections obtained from 3 healthy subjects candidate for partial liver donation served as controls. Histological evaluations were performed by two experienced pathologists, and diagnoses established based on international criteria. The intensity of the PTEN staining in nuclei was compared between steatotic and non-steatotic areas of each liver fragment analyzed. For each liver specimen, the antibody-stained sections were examined and scored blindly by three independent observers, who were unaware of the patients’ clinical ***: In healthy individuals, PTEN immunostaining was intense in both the cytoplasm and nuclei of all hepatocytes. However, PTEN was strongly downregulated in both the nucleus and the cytoplasm of hepatocytes from steatotic areas in patients with NAFLD, independently of the disease stage. In contrast, no changes in PTEN protein expression were observed in patients with ALD, regardless of the presence of steatosis or the stage of the disease. The degree of PTEN downregulation in hepatocytes of patients with NAFLD correlated with the percentage of steatosis (r = 0.3061, P = 0.0459) and the BMI (r = 0.4268, P = 0.0043). Hovewer, in patients with ALD, PTEN expression was not correlated with the percentage of steatosis with or without obesity as a confounding factor (P = 0.5574). Finally, PTEN expression level in steatotic areas of ALD patients was significantly different from that seen in steatotic areas of NAFLD patients (P clUSION: PTEN protein expression is downregulated early in NAFLD, but not in ALD. PTEN imm

关键词： Fibrosis Phosphatase and tensin homolog Steatosis Non-alcoholic fatty liver disease Nonalcoholic steatohepatitis Alcoholic liver disease Cirrhosis Hepatocellular carcinoma

MEC-based architecture for interoperable and trustworthy internet of moving things

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Digital Communications and Networks 2023年第1期9卷 270-279页

作者： Jesus sanchez-Gomez Rafael Marin-Perez Ramon sanchez-Iborra Miguel Angel Zamora Department of Information and Communications Engineering University of MurciaMurciaSpain Odin Solutions S.L. MurciaSpain University Center of Defense San Javier Air Force BaseMurciaSpain

The expansion of the Internet of Moving Things(IoMT)leads to limitless and continuous working playgrounds exploited by highly dynamic end *** requires the adoption of multi-Radio Access Technologies(RATs)-based strategies to provide IoMT units with ubiquitous *** this end,the development of secure bootstrapping and authentication mechanisms is necessary to permit the secure operation of end *** the transmission and power limitations of these elements,current cryptographic solutions do not address these stringent *** that reason,in the study we present a Multi-Access Edge Computing(MEC)-based endto-end architecture that enables an efficient and secure authentication and key agreement between end devices and network servers over heterogeneous resource-limited networks such as the Low Power Wide Area Networks(LPWANs).Our proposal is based on the Authentication,Authorization,and Accounting(AAA)architecture and the recent Internet Engineering Task Force initiatives Static Context Header Compression and Low-Overhead *** results obtained from experimental tests reveal the validity of the proposal as it enables constrained IoMT devices to gain IPv6 connectivity as well as performs end-to-end secure authentication with notable reliability and controlled latency.

关键词： Internet of moving things LPWAN Authentication LO-CoAP-EAP SCHC

Reactive oxygen species and antioxidant properties from mushrooms

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Synthetic and Systems Biotechnology 2017年第1期2卷 13-22页

作者： Carmen sanchez Laboratory of Biotechnology Research Centre for Biological SciencesUniversidad Autonoma de TlaxcalaIxtacuixtlaTlaxcalaCP.90062Mexico

Preventive medicine and food industry have shown an increased interest in the development of natural antioxidants,since those most commonly used synthetic antioxidants may have restricted use in *** could explain why there is currently much research on the antioxidant properties from natural products such as *** mushrooms have been reported to possess antioxidant properties,which enable them to neutralize free *** oxygen molecule is a free radical,which lead to the generation of the reactive oxygen species and can damage the *** damage caused by free radicals appears to be a major contributor to aging and degenerative *** antioxidant components are found in fruit bodies,mycelium and culture both,which include polysaccharides,tocopherols,phenolics,carotenoids,ergosterol and ascorbic acid among *** bodies or mycelium can be manipulated to produce active compounds in a relatively short period of time,which represent a significant advantage in antioxidant compounds extraction from *** compounds may be extracted to be used as functional additives or mushrooms can be incorporated into our food regime,representing an alternative source of food to prevent damage caused by oxidation in the human body.

关键词： Antioxidant Fruit body Mushroom Mycelium Reactive oxygen species

Laplace plane and low inclination geosynchronous radar mission design

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Science China(Information Sciences) 2017年第6期60卷 62-71页

作者： Stephen HOBBS Joan Pau sanchez School of Aerospace Transport and Manufacturing Cranfield University

This study is inspired by the Laplace orbit plane property of requiring minimal station-keeping and therefore its potential use for long-term geosynchronous synthetic aperture radar(GEOSAR) imaging. A set of GEOSAR user requirements is presented and analysed to identify significant mission requirements. Imaging geometry and power demand are assessed as a function of relative satellite speed(which is determined largely by choice of orbit inclination). Estimates of the cost of station-keeping as a function of orbit inclination and right ascension are presented to compare the benefits of different orbit choices. The conclusion is that the Laplace plane(and more generally, orbits with inclinations up to 15°) are attractive choices for GEOSAR.

关键词： Laplace plane station-keeping geosynchronous inclination GEOSAR

Vee-tail conceptual design criteria for commercial transport aeroplanes

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Chinese Journal of Aeronautics 2019年第3期32卷 595-610页

作者： Alejandro sanchez-CARMONA Cristina CUERNO-REJADO Faculty of Aerospace Engineering Department of Aircraft and Spacecraft Technical University of Madrid (Universidad Poltécnica de Madrid)

Vee-tail configuration is an unconventional tail configuration for commercial transport aviation, the use of which could suppose reductions on CO2 emissions. The conceptual design criteria have been selected inspired on the certification requirements established by the aviation regulation in force. They are static stability in cruise, control after Critical Engine Failure(CEF),control in crosswind landing, and trim in these three conditions. The study is carried out through a combination of semi-empirical techniques and Vortex-Lattice Methods(VLM) and thus this analyses the consequences of applying these criteria to a reference aeroplane substituting its conventional tail by a parametrised Vee-tail configuration. The Vee-tail is defined by four parameters:span, root chord, taper ratio and dihedral angle. The results of the study establish a relation between the parameters in order to accomplish the proposed conceptual design criteria. To sum up, minimum and maximum limits are obtained for dihedral angle depending on the combination of the rest of parameters. In addition, a design restriction to the yawing trailing-edge tail control is reached when the results are analysed, demonstrating that its minimum size must be between 60%and 80% of the half-span of the tail, depending on the Vee-tail geometry.

关键词： Commercial transport aeroplane Conceptual aircraft design Tail design requirements Unconventional tail design Vee-tail

High-Efficiency DC-DC Converter for Large Input-Voltage Fluctuations in Solar Applications

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Chinese Journal of Electronics 2015年第3期24卷 502-507页

作者： AGUILLON-GARCIA Jacobo BANUELOS-sanchez Pedro SIST Sun Yat-sen University

In the solar energy systems the solar irradiance variation is partially engaged, limiting the converter’s transformation rate for a certain input amount and leaving the rest of energy unconverted. In order to utilize at its maximum the energy provided from a Photovoltaic(PVP) system, this manuscript proposed a topology that can cope with marginal input voltage variations from 60V(DC) up to 1050V(DC) for a steady output voltage of 700V(DC). This output voltage value is suitable for any interlink post-regulation architecture. Based on previous observations, this paper presents a wide-input voltage high-efficiency non-isolated single-control topology. Analysis, operating stages, simulations and experimental results for a 3k W prototype are presented.

关键词： DC-DC power converters Energy conversion Photovoltaic system Power conditioning Solar generation

Taxonomy-based differences in feeding guilds of fish

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Current Zoology 2020年第1期66卷 51-56页

作者： Javier sanchez-HERNANDEZ Departamento de Zooloxla Xenetica e Antropoloxfa FlsicaFacultade de BioloxfaUniversidade de Santiago de CompostelaCampus Vida s/nSantiago de CompostelaEspana

It has been taken for granted that feeding guilds and behavior in animals are linked to the taxonomic relatedness of species,but empirical evidence supporting such relationship is virtually *** examine the importance of taxonomy on trophic ecology,I here present the first well-resolved dietary taxonomy analysis based on feeding guilds(predation,herbivory,and filtering)among families and genera within the fish order *** relatedness in feeding did not vary with ecosystem dimension(marine ***).Although predation dominates among Perciformes fishes,this study shows that in most cases taxonomic units(family or genus)are composed by species with several feeding *** species are more similar in feeding compared with species that are taxonomically more distant demonstrating that there is a greater variation of feeding guilds within families than ***,there is no consistency in feeding guilds between family-and genus-level *** study provides empirical support for the notion that genera are more informative than families,underlining that family-level taxonomy should be avoided to infer feeding habits of fish species at finer taxonomic ***,the choice of taxonomic resolution(family or genus level)in ecological studies is key to avoid information loss and misleading results.I conclude that high-rank taxonomic units(i.e.,above the generic level)are not appropriate to test research hypotheses about the feeding of fish.

关键词： aquatic systems clades FishBase global datasets taxonomic sufficiency trophic ecology

Canopy arthropods community within and among oak species in central Mexico

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Current Zoology 2009年第2期55卷 132-144页

作者： Efraín TOVAR-sanchez CEAMISH Universidad Autónoma del Estado de MorelosAv. Universidad No. 1001Col. ChamilpaC. P.62209Cuernavaca MorelosMéxico

Quercus rugosa and *** are species that presents a wide geographical distribution range in temperate forests of Mexico. Oak canopies contain a considerable portion of arthropod diversity and the arthropods fauna fulfill a wide variety of ecological roles. We examined the effect of oak species and seasonal changes on some community structure parameters (diversity,composition,similarity,biomass,rare species,and density of arthropod fauna) of canopy arthropods. In total,40 oak canopies were fogged during rainy and dry season. A total of 614 identified arthropod morphospecies were recognized belonging to 22 orders associated with tree canopies. A separation of host tree species during both seasons,suggesting a different community structure on host plants species was demonstrated by the principal component analyses (PCA),therefore,differences between oak species results in phenotypes that structure the composition of the arthropod community. *** registered the highest densities,diversity index and number of rare species in comparison with ***. While arthropod biomass showed an inverse pattern. Trees more close to one another (spatial distance) register a more similar canopy arthropod fauna. This study suggests that the trees of *** could act as a center of biodiversity by the accumulation of arthropod fauna with a considerable number of rare species,which presents wide ecological roles or is involved in critical processes that maintain forest ecosystems.

关键词： Canopy arthropods Quercus Species diversity Species biomass Rare species

Neurotoxicity of the pesticide rotenone on neuronal polarization: a mechanistic approach

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Neural Regeneration Research 2019年第5期14卷 762-766页

作者： Mariano Bisbal Mónica sanchez Laboratory of Neurobiology Instituto Mercedes y Martín Ferreyra (INIMEC-CONICET) Universidad Nacional de Córdoba Instituto Universitario Ciencias Biomédicas Córdoba

Neurons are the most extensive and polarized cells that display a unique single long axon and multiple dendrites, which are compartments exhibiting structural and functional differences. Polarity occurs early in neuronal development and it is maintained by complex subcellular mechanisms throughout cell life. A well-defined and controlled spatio-temporal program of cellular and molecular events strictly regulates the formation of the axon and dendrites from a non-polarized cell. This event is critical for an adequate neuronal wiring and therefore for the normal functioning of the nervous system. Neuronal polarity is very sensitive to the harmful effects of different factors present in the environment. In this regard, rotenone is a crystalline, colorless and odorless isoflavone used as insecticide, piscicide and broad spectrum pesticide commonly used earlier in agriculture. In the present review we will summarize the toxicity mechanism caused by this pesticide in different neuronal cell types, focusing on a particular biological mechanism whereby rotenone could impair neuronal polarization in cultured hippocampal neurons. Recent advances suggest that the inhibition of axonogenesis produced by rotenone could be related with its effect on microtubule dynamics, the actin cytoskeleton and their regulatory pathways, particularly affecting the small RhoGTPase RhoA. Unveiling the mechanism by which rotenone produces neurotoxicity will be instrumental to understand the cellular mechanisms involved in neurodegenerative diseases influenced by this environmental pollutant, which may lead to research focused on the design of new therapeutic strategies.

关键词： rotenone environmental pollutants toxicity neuronal polarity RhoGTPase RhoA Lfc Arhgef1