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Assessing above-ground biomass-functional diversity relationships in temperate forests in northern mexico

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Forest Ecosystems 2021年第1期8卷 95-108页

作者： Benedicto Vargas-Larreta Jorge Omar López-martínez Edgar J.González joséJavier Corral-Rivas Francisco Javier Hernández Tecnológico Nacional de méxico/Instituto Tecnológico de El Salto 34942 El SaltoDurangoMexico Cátedras CONACYT1582Av.Insurgentes SurCiudad de MéxicoMexico El Colegio de la Frontera Sur 77014ChetumalQuintana RooMexico Departamento de Ecología y Recursos Naturales Facultad de CienciasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMexico Facultad de Ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120 DurangoMexico

Background:Studies on the relationship between biodiversity and ecosystem productivity have suggested that species richness and functional diversity are the main drivers of ecosystem *** patterns on this relationship have been found,including positive,unimodal,negative,and neutral trends,keeping the issue *** this study,taxonomic diversity and functional diversity as drivers of above-ground biomass(AGB)were compared,and the mechanisms that influence biomass production were investigated by testing the complementarity and the mass-ratio ***:Using data from 414 permanent sample plots,covering 23%of temperate forest in the Sierra madre Oriental(méxico),we estimated the above-gound biomass(AGB),taxonomic and functional diversity indices,as well as community weighted mean values(CWm)for three functional traits(maximum height,leaf size and wood density)for trees≥7.5 cm DBH,in managed and unmanaged *** compare taxonomic diversity differences between managed and unmanaged stands we carried out a rarefaction ***,we evaluated the relationship between AGB and taxonomic and functional diversity metrics,as well as CWm traits throught spatial autoregressive ***:We found a hump-shaped relationship between AGB and species richness in managed and unmanaged *** of maximum height was the most important predictor of AGB in both stands,which suggested that the mechanism underlaying the AGB-diversity relationship is the dominance of some highly productive species,supporting the mass-ratio ***-ground biomass was significantly correlated with three of the five functional diversity metrics,CWm maximum height and species *** results show the importance of taking into account spatial autocorrelation in the construction of predictive models to avoid spurious patterns in the AGBdiversity ***:Species richness,maximum height,functional richness,functional dispersion and Rao

关键词： Taxonomic diversity Functional diversity Complementarity hypothesis mass-ratio hypothesis

Phenolic metabolism and molecular mass distribution of polysaccharides in cellulose-deficient maize cells

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Journal of Integrative Plant Biology 2017年第7期59卷 475-495页

作者： maría de Castro Romina martínez-Rubio josé L.Acebes Antonio Encina Stephen C.Fry Penélope García-Angulo área de Fisiología Vegetal.Dpto.Ingenieríay Ciencias Agrarias.Facultad de Biologíay Ciencias Ambientales.Universidad de León The Edinburgh Cell Wall Group Institute of Molecular Plant Sciences School of Biological Sciences Daniel Rutherford BuildingThe King's Buildings

As a consequence of the habituation to low levels of dichlobenil （DCB）, cultured maize cells presented an altered hemicellulose cell fate with a lower proportion of strongly wall-bound hemicelluloses and an increase in soluble extracellular polymers released into the culture medium. The aim of this study was to investigate the relative molecular mass distributions of polysaccharides as well as phenolic metabolism in cells habituated to low levels of DCB （1.5 μm）. Generally, cell wall bound hemicelluloses and sloughed polymers from habituated cells were more homogeneously sized and had a lower weight-average relative molecular mass. In addition, polysaccharides underwent massive cross-linking after being secreted into the cell wall, but this cross-linking was less pronounced in habituated cells than in non-habituated ones. However, when relativized, ferulic acid and p-coumaric acid contents were higher in this habituated cell line. Feasibly, cells habituated to low levels of DCB synthesized molecules with a lower weight-average relative molecular mass, although cross-linked, as a part of their strategy to compensate for the lack of cellulose.

关键词： Phenolic metabolism and molecular mass distribution of polysaccharides in cellulose-deficient maize cells were for

The paradigm of protein acetylation in Parkinson's disease

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Neural Regeneration Research 2019年第6期14卷 975-976页

作者： Sokhna m.S.Yakhine-Diop Guadalupe martínez-Chacón Elisabet Uribe-Carretero mireia Niso-Santano Rosa A.González-Polo josé m.Fuentes Universidad de Extremadura Departamento de Bioquímicay Biología Moleculary GenéticaFacultad de Enfermeríay Terapia Ocupacional Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED) Instituto de Investigación Biosanitaria de Extremadura (INUBE)

Acetylation is a post-translational modification that is regulated by two antagonistic enzymes,histone acetyltransferases(HATs)and histone deacetylases(HDACs).HATs transfer the acetyl group from acetyl-CoA to lysine residues of proteins while HDACs remove it(Yakhine-Diop et al.,2018b).The impairment of HAT or HDAC activity elicits changes in the protein acetylation status which disturb several cellular processes,among others,gene expression,autophagy etc.,leading finally to cell *** enzymes are associated with Parkinson’s disease(PD)*** dopaminergic cells,neurotoxins provoke apoptotic cell death by increasing histone acetylation *** paraquat(Song et al.,2011)and rotenone(Feng et al.,2015)reduce HDAC activity,dieldrin(Song et al.,2010)enhances HAT *** in vivo,paraquat-induced upregulation ofα-synuclein triggers histone hypoacetylation.

关键词： Parkinson protein α-synuclein HDACs cells gene is

Processing of Aerosol Particles in Convective Cumulus Clouds:Cases Study in the mexican East Pacific

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Advances in Atmospheric Sciences 2010年第6期27卷 1331-1343页

作者： josé C.JImnez-ESCALONA Oscar PERALTA ESImE UP Ticomán National Polytechnic Institute Chemistry Faculty National Autonomous University of MexicoCiudad Universitaria

In the mexican Intertropical Convergence Zone, particle size distributions within 500 m of cloud boundaries at altitudes of 1000, 2500, and 4200 m, were compared against size distributions at the same levels but 1500 m away from the clouds. The differences in the distributions near and far from the cloud are related to processes that may change particle properties inside the cloud. Chemical changes in the aerosols are deduced from the particles＇ refractive index, as derived from comparisons with the scattering coeflcient measured by a nephelometer. An analysis of ten cloud systems indicates that vertical transport of cloud base aerosol followed by entrainment/detrainment is the cloud processing signature most frequently observed in the comparisons （65%）. Changes in the chemical composition are observed in approximately 20% of the cases and another 20% of the cases showed removal by precipitation. About 5% of the comparisons showed clear evidence of changes by coalescence. The principal effect of these cloud-processed aerosols is observed in the increase of optical depth in the layer from 30 m to 4200 m in the near-cloud regions, in comparison with the atmosphere further from clouds.

关键词： cloud processing cloud interaction scattering redistribution entrainment

In vivo testing of mucus-permeating nanoparticles for oral insulin delivery using Caenorhabditis elegans as a model under hyperglycemic conditions

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Acta Pharmaceutica Sinica B 2021年第4期11卷 989-1002页

作者： Ana Lmartínez-López Carlos JGonzález-Navarro Paula Aranaz joséLVizmanos Juan mIrache NANO-VAC Research Group Department of Chemistry and Pharmaceutical TechnologySchool of Pharmacy and NutritionUniversity of NavarraPamplona 31080Spain Center for Nutrition Research School of Pharmacy and NutritionUniversity of NavarraPamplona 31080Spain Department of Biochemistry&Genetics School of ScienceUniversity of NavarraPamplona 31080Spain Navarra Institute for Health Research(IdiSNA) Pamplona 31080Spain

The aim was to evaluate the potential of mucus-permeating nanoparticles for the oral administration of *** nanocarriers,based on the coating of zein nanoparticles with a polymer conjugate containing PEG,displayed a size of 260 nm with a negative surface charge and an insulin payload of 77 mg/*** intestinal pig mucus,the diffusivity of these nanoparticles(PPA-NPs)was found to be 20-fold higher than bare nanoparticles(NPs).These results were in line with the biodistribution study in rats,in which NPs remained trapped in the mucus,whereas PPA-NPs were able to cross this layer and reach the epithelium *** therapeutic effcacy was evaluated in Caenorhabditis elegans grown under high glucose *** this model,worms treated with insulin-loaded in PPA-NPs displayed a longer lifespan than those treated with insulin free or nanoencapsulated in *** finding was associated with a signifcant reduction in the formation of reactive oxygen species(ROS)as well as an important decrease in the glucose and fat content in *** effects would be related with the mucus-permeating ability of PPA-NPs that would facilitate the passage through the intestinal peritrophic-like dense layer of worms(similar to mucus)and,thus,the absorption of insulin.

关键词： Nanoparticles Oral delivery mucus-permeating Biodistribution Insulin Caenorhabditis elegans ROS

Yield models for predicting aboveground ectomycorrhizal fungal productivity in Pinus sylvestris and Pinus pinaster stands of northern Spain

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Forest Ecosystems 2019年第4期6卷 414-426页

作者： mariola Sánchez-González Sergio de-miguel Pablo martin-Pinto Fernando martínez-Pe?a maría Pasalodos-Tato Juan Andrés Oria-de-Rueda Juan martínez de Aragón Isabel Ca?ellas josé Antonio Bonet Spanish National Institute for Agricultural and Food Research and Technology (INIA)

Background: Predictive models shed light on aboveground fungal yield dynamics and can assist decision-making in forestry by integrating this valuable non-wood forest product into forest management planning. However, the currently existing models are based on rather local data and, thus, there is a lack of predictive tools to monitor mushroom yields on larger ***: This work presents the first empirical models for predicting the annual yields of ectomycorrhizal mushrooms and related ecosystem services in Pinus sylvestris and Pinus pinaster stands in northern Spain, using a long-term dataset suitable to account for the combined effect of meteorological conditions and stand *** were fitted for the following groups of fungi separately: all ectomycorrhizal mushrooms, edible mushrooms and marketed mushrooms. Our results show the influence of the weather variables(mainly precipitation) on mushroom yields as well as the relevance of the basal area of the forest stand that follows a right-skewed unimodal curve with maximum predicted yields at stand basal areas of 30–40 m2·***: These models are the first empirical models for predicting the annual yields of ectomycorrhizal mushrooms in Pinus sylvestris and Pinus pinaster stands in northern Spain, being of the highest resolution developed to date and enable predictions of mushrooms productivity by taking into account weather conditions and forests’ location, composition and structure.

关键词： mushrooms Fungi Non-wood forest products mixed models Hurdle models

Suicidal Behaviours in Sickle Cell Patients at the Douala Sickle Cell Care Centre in Cameroon

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Open Journal of Psychiatry 2024年第3期14卷 265-281页

作者： Christian Eyoum Léonce Kengno Kologne Charlotte Eposse Ekoube Annick mélanie magnerou joséphine manga Befolo Cindy Laura Ndepa Daniel Gams massi Aurore Nzesseu Djomo Guy Jonas Basseguin Atchou Guy Calvin mbongo’O Rihta mbono mbekoto Iyawa Hassanatou Fabiola Tchouankeu Kounga Christiane medi Sike josiane Essola Jacques Narcisse Doumbe Erero Njiengwe Callixte Kuate Tegueu Faculty of medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Laquintinie Hospital Douala Cameroon Faculty of Health Sciences University of Buea Buea Cameroon Faculty of medicine and Biomedical Sciences University of Yaound&#233 1 Yaound&#233 Cameroon

Introduction: Sickle cell anaemia is a hereditary disease that combines physical and psychological manifestations, including suicidal tendencies. So far, to our knowledge, no study has been conducted on suicidal behaviours among people with sickle cell disease in Cameroon. This is what justifies our study on the prevalence and factors related to suicidal behaviors in our study population. methods: We conducted a cross-sectional, analytical study of 171 sickle cell patients aged from 12 years upwards who came to the sickle cell disease care service of the Laquintinie Hospital in Douala, over a period of 6 months, that is, from 1 January to 31 June 2022. Data were collected using a structured questionnaire with questions on suicidal behaviours based on the “mINI” (mini International Neuropsychiatric Interview). The data were processed using the SPSS 26.0 software. The related factors were studied in both a bivariate and multivariate analysis. Results: Female sickle cell patients accounted for 60.2% of the sample. The mean age was 23.36 ± 8.42 years. Suicidal ideation was prevalent in 56% of cases and 13% attempted suicide. The factors most associated with suicidal ideation were: primary level of education (OR = 0.08 (0.09 - 0.79);p = 0.03), feeling unworthy of life (OR = 0.40 (0.08 - 1.96);p = 0.02), not often being considered by those around them (OR = 2.97 (1.26 - 6.99);p = 0.01), lack of family support (OR = 0.34 (0.15 - 0.77);p = 0.01). meanwhile, the factors associated with suicide attempts were: the fact of being rarely exposed to suicide-related media (OR = 4.17 (1.40 - 71.80);p = 0.03), and a constant feeling of sadness when returning home (OR = 18.02 (1.59 - 20.55);p = 0.01). Conclusion: more than half of sickle cell patients had had suicidal thoughts and 1/6 had made at least one suicide attempt, women and young adults being the most concerned. It is therefore necessary to ensure optimum psychological care for patients with sickle cell disease.

关键词： Sickle Cell Disease Suicidal Behaviours Self-Harm

Endoscopic ultrasound-guided gastroenterostomy for gastric outlet obstruction in mexico

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World Journal of Surgical Procedures 2024年第3期14卷 15-20页

作者： massiel madelin Rosario-morel Rodrigo Soto-Solis Katia Picazo-Ferrera miriam Idalia Torres-Ruiz joséAlberto Estradas-Trujillo mario Alberto Gallardo-Ramírez Gerardo Akram Darwich-del moral Luis Ariel Waller-González Department of Endoscopy Centro Médico Nacional“20 de Noviembre”ISSSTEMexico City 03229Mexico Department of Gastroenterology HospitalÁngeles PedregalMexico City 10700Mexico Department of Endoscopy Centro Médico ABCMexico City 01120Mexico Department of Endoscopy Hospital General de México“Dr.Eduardo Liceaga”Mexico City 06720Mexico

BACKGROUND Endoscopic ultrasound-guided gastroenterostomy(EUS-GE)has recently emerged as an alternative treatment for gastric outlet obstruction(GOO)in selected *** To report the initial experience of EUS-GE in patients with *** This study was a retrospective,observational,multicenter study in which the data from 10 patients who underwent EUS-GE due to GOO between September 2021 and may 2023 were *** analyzed technical success,clinical success,adverse events,and *** success was defined as adequate positioning and deployment of the *** success was defined as the patient’s ability to tolerate oral intake without vomiting 7 d after the *** adverse events were *** Eleven procedures in 10 patients with GOO were *** mean age of the patients was 67.5 years(range:56-77 years).malignant GOO was present in 9 *** success was achieved in 9/11 procedures(82%).Among them,clinical success was achieved in 9 patients(100%).Adverse events occurred in 1 patient(9%).The median survival was 3 months(n=7;range:1-8 months).CONCLUSION EUS-GE is a feasible therapeutic option in the treatment of GOO.

关键词： Endoscopic ultrasound-guided gastroenterostomy Gastric outlet obstruction Lumen apposing metal stent Interventional endoscopic ultrasound Gastrojejunostomy Duodenal stenting

Sticky-martINI as a reactive coarse-grained model for molecular dynamics simulations of silica polymerization

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npj Computational materials 2022年第1期8卷 467-479页

作者： AndréP.Carvalho Sérgio m.Santos Germán Pérez-Sánchez joséD.Gouveia joséR.B.Gomes miguel Jorge CICECO-Aveiro Institute of materials Department of ChemistryUniversity of AveiroCampus Universitário de Santiago3810-193AveiroPortugal Department of Chemical and Process Engineering University of Strathclyde75 Montrose StreetGlasgowG11XJUK

We report a molecular modeling paradigm to describe silica polymerization reactions in aqueous solutions at conditions that are representative of realistic experimental processes like biosilicification or porous silica synthesis–*** close to ambient temperatures and over a wide range of *** key point is to describe the Si-O-Si chemical bond formation and breakage processes through a continuous potential with a balance between attractive and repulsive interactions between suitably placed virtual sites and sticky *** simplicity of the model,its applicability in standard parallelized molecular dynamics codes,and its compatibility with the widely used martINI coarse-grained force-field allows for the study of systems containing millions of atoms over microsecond time *** model is calibrated to match experimental results for the temporal evolution of silica polymerization in aqueous solution close to the isoelectric point,and can describe silica polymerization and self-assembly processes during encapsulation of a surfactant micelle.

关键词： silica polymerization dynamics