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Role of hyperfine mixing in b→c semileptonic decays of doubly-heavy baryons

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chinese Physics c 2010年第9期34卷 1488-1490页

作者： c.Albertus E.hernández J.Nieves Departamento de Física Fundamental e IUFFyM Universidad de Salamanca Instituto de Física corpuscular (IFIc) Centro Mixto CSIC-Universidad de ValenciaInstitutos de Investigación de Paterna

We analyze the effects of hyperfine mixing in b → c semileptonic decays of doubly heavy *** qualitatively confirm the results by *** and *** in ***.A,2009,24： 2401– 2413,finding that mixing has a great impact on those ***,predictions without mixing differ by a factor of 2 and this discrepancy translates to the mixed case where large differences in decay widths are observed between the two calculations.

关键词： doubly-heavy baryons semileptonic decay hyperfine mixing

A photoswitchable organocatalyst controls trimethylene carbonate and δ-valerolactone copolymerization

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Science Bulletin 2018年第22期63卷 1460-1461页

作者： Madeline N.Riffel Zachary c.hern Paula L.Diaconescu Department of chemistry and Biochemistry University of California

Switchable catalysts can be reversibly altered to produce two (or more)states displaying orthogonal *** use of compounds containing a "switchable"unit in ring opening polymerization (ROP)of cyclic esters and ethers has been an attractive area of research due to the biosourced and biodegradable nature of the polymers produced and enhanced control of the polymer structure. Such systems for ROP have been reported using various stimuli such as temperature [1],redox [2-6] or chemical reagents [7,8], electrodes [9],and,recently,light [10].

关键词：催化剂状态

Design of multilayer hybrid sol-gel coatings with bifunctional barrier-bioactive response on the Elektron 21 magnesium alloy for biomedical applications

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Journal of Magnesium and Alloys 2021年第6期9卷 2097-2112页

作者： K.S.Durán N.hernández L.M.Rueda c.A.hernández-Barrios A.E.coy F.Viejo Grupo de Investigación en Desarrollo y Tecnología de Nuevos Materiales(GIMAT) Universidad Industrial de Santander9 Cra.27Colombia Grupo de Investigación de las ciencias de las Ingenierías(GIcI) Universidad de San BuenaventuraCartagenaCalle Real de TerneraDiagonal 32#30-966Colombia

The present study aims to develop multilayer barrier-bioactive hybrid sol-gel coatings from a mixture of the silane precursors tetraethylorthosilicate(TEOS)and glycidoxypropyltriethoxysilane(GPTMS)deposited on the Elektron 21 magnesium *** purpose of the inner layer(barrier coating)was to provide corrosion protection to the magnesium alloy,whereas the outer layer(bioactive coating)was doped with different ca and Mg contents to produce a bioactive *** coatings were characterised using scanning electron microscopy(SEM)and their corrosion behaviour was evaluated by anodic polarisation and electrochemical impedance spectroscopy after immersion in simulated body fluid(SBF)at 37±0.5°*** experimental results showed that the multilayer coatings increased the corrosion resistance of the alloy up to three orders of magnitude during immersion in SBF *** the other hand,the presence of ca and Mg in the bioactive coating promoted the growth of apatite-like ***,an increment of salt content favoured the formation of porous coatings,which allowed the access of the electrolyte to the substrate leading to their rapid *** the latter,this research endorses the premise that the TEOS-GPTMS hybrid system represents a promising alternative to produce bifunctional barrier-bioactive coatings.

关键词： Magnesium bioactivity coating sol-gel EIS corrosion

Thrombin activation and liver inflammation in advanced hepatitis c virus infection

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World Journal of Gastroenterology 2016年第18期22卷 4427-4437页

作者： Emilio González-Reimers Geraldine Quintero-Platt candelaria Martín-González Onán Pérez-hernández Lucía Romero-Acevedo Francisco Santolaria-Fernández Servicio de Medicina Interna Hospital Universitario de Canarias Universidad de La Laguna

Hepatitis c virus(HcV) infection is associated with increased thrombotic risk. Several mechanisms are involved including direct endothelial damage by the HcV virus, with activation of tissue factor, altered fibrinolysis and increased platelet aggregation and activation. In advanced stages, chronic HcV infection may evolve to liver cirrhosis, a condition in which alterations in the portal microcirculation may also ultimately lead to thrombin activation, platelet aggregation, and clot formation. Therefore in advanced HcV liver disease there is an increased prevalence of thrombotic phenomena in portal vein radicles. Increased thrombin formation may activate hepatic stellate cells and promote liver fibrosis. In addition, ischemic changes derived from vascular occlusion by microthrombi favor the so called parenchymal extinction, a process that promotes collapse of hepatocytes and the formation of gross fibrous tracts. These reasons may explain why advanced HcV infection may evolve more rapidly to end-stage liver disease than other forms of cirrhosis.

关键词： coagulation Liver cirrhosis Hepatitis c virus Fibrogenesis Parenchymal extinction Portal thrombosis Protein c

chemical-Structural changes of Organic Matter in a Semi-Arid Soil After Organic Amendment

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Pedosphere 2012年第3期22卷 283-293页

作者： c.NIcOLS G.MAScIANDARO T.hernndez c.GARcIA centro de Edafología y Biología Aplicada del Segura (cEBAS-cSIc) Department of Soil and Water Conservation and Organic Wastes ManagementCampus Universitario de EspinardoP.O.160Murcia 3010 (Spain) consiglio Nazionale delle Ricerche (cNR) Istituto per lo Studio degli Ecosistemi (ISE)-Sezione di Chimica del SuoloArea della RicercaVia Moruzzi 1Pisa 56124 (Italy)

A 9-month incubation experiment using composted and non-composted amendments derived from vine pruning waste and sewage sludge was carried out to study the effects of the nature and stability of organic amendments on the structural composition of organic matter (OM) in a semi-arid *** changes of soil OM,both in the whole soil and in the extractable carbon with pyrophosphate,were evaluated by pyrolysis-gas chromatography and chemical *** the end of the experiment,the soils amended with pruning waste exhibited less organic carbon loss than those receiving sewage *** non-composted residues increased the aliphatic-pyrolytic products of the OM,both in the whole soil and also in the pyrophosphate extract,with the products derived from peptides and proteins being significantly *** 9 months,in the soils amended with pruning waste the relative abundance of phenolic-pyrolytic products derived from phenolic compounds,lignin and proteins in the whole soil tended to increase more than those in the soils amended with sewage ***,the extractable OM with pyrophosphate in the soils amended with composted residues tended to have higher contents of these phenolic-pyrolytic products than that in non-composted ***,despite the stability of pruning waste,the composting of this material promoted the incorporation of phenolic compounds to the soil *** pyrolytic indices (furfural/pyrrole and aliphatic/aromatic ratios) showed the diminution of aliphatic compounds and the increase of aromatic compounds,indicating the stabilization of the OM in the amended soils after 9 *** conclusion,the changes of soil OM depend on the nature and stability of the organic amendments,with composted vine pruning waste favouring humification.

关键词： degraded soil pyrolysis-gas chromatography pyrophosphate extract sewage sludge vine pruning waste

Management of betablocked patients after sustained virological response in hepatitis c cirrhosis

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World Journal of Gastroenterology 2019年第21期25卷 2665-2674页

作者： Marta Abadía María Luisa Montes Dolores Ponce consuelo Froilán Miriam Romero Joaquín Poza Teresa hernández Rubén Fernández-Martos Antonio Olveira Antonio Olveira Servicio de Aparato DigestivoHospital Universitario La PazMadrid 28046Spain Unidad VIH Servicio de Medicina InternaHospital Universitario La PazMadrid 28046Spain Servicio de Radiología Hospital Universitario La PazMadrid 28046Spain cIBERehd IdiPAZ Madrid 28029Spain

BAcKGROUND current guidelines do not address the post–sustained virological response management of patients with baseline hepatitis c virus (HcV) cirrhosis and oesophageal varices taking betablockers as primary or secondary prophylaxis of variceal bleeding. We hypothesized that in some of these patients portal hypertension drops below the bleeding threshold after sustained virological response, making definitive discontinuation of the betablockers a safe option. AIM To assess the evolution of portal hypertension, associated factors, non-invasive assessment, and risk of stopping betablockers in this population. METHODS Inclusion criteria were age > 18 years, HcV cirrhosis (diagnosed by liver biopsy or transient elastography > 14 kPa), sustained virological response after directacting antivirals, and baseline oesophageal varices under stable, long-term treatment with betablockers as primary or secondary bleeding prophylaxis. Main exclusion criteria were prehepatic portal hypertension, isolated gastric varices, and concomitant liver disease. Blood tests, transient elastography, and upper gastrointestinal endoscopy were performed. Hepatic venous pressure gradient (HVPG) was measured five days after stopping betablockers. Betablockers could be stopped permanently if gradient was cretion of the attending physician. RESULTS Sample comprised 33 patients under treatment with propranolol or carvedilol: median age 64 years, men 54.5%, median Model for End-Stage Liver Disease (MELD) score 9, child-Pugh score A 77%, median platelets 77.000 × 103/μL, median albumin 3.9 g/dL, median baseline transient elastography 24.8 kPa, 88% of patients received primary prophylaxis. Median time from end of antivirals to gradient was 67 wk. Venous pressure gradient was ciated factor was a MELD score decrease from baseline. On endoscopy, variceal size regressed in 19/27 patients (70%), although gradient was

关键词： Hepatitis c virus Oesophageal varices Portal hypertension Betablocker Variceal bleeding

Effect of retained austenite and nonmetallic inclusions on the thermal/electrical properties and resistance spot welding nuggets of Si-containing TRIP steels

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International Journal of Minerals,Metallurgy and Materials 2019年第1期26卷 52-63页

作者： V.H.Vargas I.Mejía V.H.Baltazar-hernández c.Maldonado Metallurgy and Materials Research Institute Universidad Michoacana de San Nicolás de Hidalgo Edificio "U" Ciudad Universitaria Materials Science and Engineering Program Autonomous University of Zacatecas

Five advanced high-strength transformation-induced plasticity(TRIP) steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical properties and the characteristics of the resistance spot welding nuggets. Electrical and thermal properties and equilibrium phases of TRIP steels were predicted using the JMatPro? software. Retained austenite and nonmetallic inclusions were quantified by X-ray diffraction and saturation magnetization techniques. The nonmetallic inclusions were characterized by scanning electron microscopy. The results show that the contents of Si, c, Al, and Mn in TRIP steels increase both the retained austenite and the nonmetallic inclusion contents. We found that nonmetallic inclusions affect the thermal and electrical properties of the TRIP steels and that the differences between these properties tend to result in different cooling rates during the welding process. The results are discussed in terms of the electrical and thermal properties determined from the chemical composition and their impact on the resistance spot welding nuggets.

关键词： transformation-induced plasticity steel retained austenite non-metallic inclusions magnetic saturation electrical properties thermal properties resistance spot welding nugget

Addition of Urban Waste to Semiarid Degraded Soil:Long-term Effect

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Pedosphere 2007年第5期17卷 557-567页

作者： F.BASTIDA J.L.MORENO c.GARc■A T.hernndez Department of Soil and Water conservation centro de Edafologia y Biologia Aplicada del Segura (cEBAS-cSIc) Campus Universitario de Espinardo30100 EspinardoMurcia (Spain).

The addition of municipal solid wastes （MSW） is considered as a possible strategy for soil rehabilitation in southeast Spain. The objective of this study was to evaluate the long-term （17 years） effect of five doses of MSW addition on the microbiological, biochemical, and physical properties of semiarid soil. Increased values of several parameters that serve as indicators of general microbiological activity, such as, basal respiration, adenosine triphosphate （ATP） or dehydrogenase activity; microbial population size （microbial biomass c）, and extracellular hydrolase activity related to macronutrient cycles, such as, urease, 3-glucosidase, and N-a-benzoyl-L-argininamide protease, were observed in the amended soils. The highest MSW doses showed the highest values in these hydrolase activities. The incorporation of municipal waste resulted in a more dense development of the plant cover, 50% greater in higher doses than in the control treatment, which generated a substantial increase in several c fractions. Total organic carbon reached 12 g kg^-1 soil with the highest MSW doses, compared to 4.30 g kg^-1 soil in the control treatment. The physical properties of the soil were also improved, showing greater percentage of stable aggregates and water holding capacity. Positive correlation coefficients between c fractions and parameters related to microbial activity and aggregate stability were observed. Although these improvements were greater in the soils receiving the highest doses of organic amendment, the increases were not proportional to the amount added, demonstrating the existence of a threshold, above which an increase in the amount of organic matter added is not reflected in an increase in the soil＇s physical, biochemical, and microbiological properties. However, the addition of municipal solid wastes proved its suitability for improving soil quality, thereby indicating the potential of such an amendment, to prevent desertification in Mediterranean areas such as th

关键词： enzyme activities long-term effect microbial biomass c municipal solid waste respiration

Use of δ^(18)O, δ^(13)c and NO_(3)^(-) to identify hydrogeochemical processes related to contamination in an aquifer located in central Mexico

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Acta Geochimica 2022年第3期41卷 367-392页

作者： JoséIván Morales-Arredondo María Aurora Armienta hernández Fátima Juárez-Aparicio Jorge Federico Landa-Arreguín Itzamna Zaknite Flores-Ocampo Natural Resources Department Institute of GeophysicsNational Autonomous University of MexicoCiudad Universitaria No.3000Col.Copilco UniversidadCoyoacan Delegation04360 MexicoCDMXMexico Earth Sciences Postgraduate Program University National Autonomous of MexicoUniversity City No.3000Col.Copilco UniversityCoyoacán Delegation04510 MexicoCDMXMexico

In this work,an isotopic analysis of δ^(18)O,δ^(13)c,and NO_(3)^(-) concentrations was carried out to identify the origin and the processes related to the contamination of an aquifer located in the state of Guanajuato,*** research identified the possible sources of δ^(13)c in *** groundwater flow,cO_(2) participates in different hydrogeochemical reactions in which the dissolution of carbonates or biochemical processes related to biodegradation stand *** data of δ^(13)c,δ^(18)O,and the hydrogeochemical behavior of NO_(3)^(-) and HcO_(3)^(-) in water,in addition to isotopic data and the chemical composition of limestones in the study area,were determined to establish the isotopic signature and the processes undergone by the *** isotopic signature of rock and water samples indicated that metamorphic limestones contributed with carbon dioxide to deep groundwater,while in the upper aquifer,bacterial metabolic reactions during nitrification–denitrification could modify the isotopic signature of δ^(13)c in some wells,although atmospheric contribution also plays a *** modification of the carbon isotopic component is related to the precipitation of calcite in specific regions of the study area,input of atmospheric cO_(2),and soil(*** possible participation of c4-type plants in the assimilation-release of carbon).This process is not confirmed or completely ruled out in this study since agriculture is excessively developed throughout the *** joint interpretation of isotopic values and the hydrogeochemical behavior of major and conservative elements help in identifying possible pollution processes in which different carbon sources are related.

关键词： ^(18)O and^(13)c isotopes Groundwater pollution Nitrate Limestone