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Tree encroachment into savannas alters soil microbiological and chemical properties facilitating forest expansion

Journal of forestry Research 2016年第5期27卷 1047-1054页

作者： Davi Rodrigo Rossatto Everlon cid Rigobelo Departamento de Biologia Faculdade de Ciencias Agrairias e veterinàrias Univ. Estadual Paulista UNESP Via de Acesso Prof. Paulo Donatto Castellane S/N Vila IndustrialJaboticabal - SP 14884-900 Brazil Departamento de Producao Vegetal Faculdade de Ciencias Agrairias e Veterinarias Univ. Estadual Paulista UNESP Viade Acesso Prof. Paulo Donatto Castellane S/N VilaIndustrial Jaboticabal - SP 14884-900 Brazil

Abstract forests have been expanding over typical savanna sites for the past 3000 years in the Neotropics. Such invasion can produce a series of environmental modifications on typical savanna; however, it remains unclear how modifications in soil properties, caused by the encroachment of woody species, facilitate the expansion of forest ecosystems under dystrophic conditions. Here we examined chemical and microbiological changes associ- ated with tree encroachment in oxisols of a Neotropical Savanna at Assis Ecological Station, Southeastern Brazil. We predicted that tree encroachment caused by typical forest species would cause significant changes in the chemical and microbiological properties of savanna soils. Soils were sampled at Assis Ecological Station, from savanna sites differing in tree encroachment （typical, dense and forested savanna） caused by decades of fire exclusion. We analysed vegetation leaf area index and leaf litter volume deposited in the studied plots and chemical （pH,organic matter, P, K, Ca, mg, A1, NO3-, NH4＋） and microbiological （microbial C biomass and dehydrogenase activity） properties of soils under distinct encroachment conditions. most soil chemical properties did not change along the tree encroachment gradient; however, total P, soil organic matter, soil microbial C and dehydrogenase activity increased from typical savanna to forested savanna. The changes in soil organic matter and dehydrogenase activity were correlated with the values of leaf area index and litter volume along the encroachment gradient. Our results demonstrate that forest species can increase carbon and phosphorus supplies in tropical savanna soils.

关键词： Dystrophic Encroachment - forest - Litter microbiological activity

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Perspectives in the treatment of pancreatic adenocarcinoma

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World Journal of Gastroenterology 2015年第31期21卷 9297-9316页

作者： Angel cid-Arregui Victoria Juarez German Cancer Research Center Trans- lational ImmunologyTumor Immunology Program Asteria Pharma GmbH 68723 OftersheimGermany

Pancreatic ductal adenocarcinoma(PDAC) is an incurable lethal disease whose incidence rate is growing. There is no effective screening for detection of early stage tumors and,in most cases,PDAC is diagnosed at advanced disease stages,when radical pancreatic resection is not possible. The aggressive nature of pancreatic tumor cells lies in the complex genetic mechanisms behind their uncontrolled capability to grow and metastasize,which involve essential adaptive changes in cellular metabolism,signaling,adhesion and immunoediting. In addition,PDAC cells promote a dense functional stroma that facilitates tumor resistance to chemotherapy and radiation. During the last two decades,gemcitabine has been the reference for the systemic treatment of PDAC. However,recently,a regimen combining fluorouracil,irinotecan,oxaliplatin,and leucovorin(fOLfIRINOx) and another combining albumin-bound paclitaxel with gemcitabine have shown clear therapeutic advantage in advanced PDAC,with survival outcomes of 11.3 and 8.5 mo on phase Ⅲ trials,respectively,over singleagent gemcitabine. With the pending issue of their higher toxicities,these regimens set the reference for ongoing and future clinical studies in advanced PDAC. In addition,the efficacy of oral fluoropyrimidine(S-1) has been well documented in Asiatic PDAC patients. The development of therapeutic approaches other than cytotoxic drugs has proven difficult in the past,with only one drug(erlotinib) approved to date. Besides,a number of agents targeting signaling pathways in tumor or stroma cells are being investigated. Likewise,immunotherapies that target PDAC in various ways are the subject of a number of clinical trials. The search for reliable biomarkers with diagnostic and prognostic value using genomics and mass spectrometry methods may facilitate monitoring and refinement of therapies. This review focuses on current understanding of the pathogenesis of PDAC and the latest developments in the treatment of advanced PDAC.

关键词： Pancreatic adenocarcinoma Tumor sur-veillance Biom

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Validation of kinetic modeling of progesterone release from polymeric membranes

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Asian Journal of Pharmaceutical Sciences 2018年第1期13卷 54-62页

作者： Analia Irma Romero mercedes Villegas Alicia Graciela cid mónica Liliana Parentis Elio Emilio Gonzo José maría Bermúdez Instituto de Investigaciones para la Industria Química Universidad Nacional de Salta – Consejo Nacional de Investigaciones Científicas y Técnicas facultad de Ingeniería Universidad Nacional de Salta

mathematical modeling in drug release systems is fundamental in development and optimization of these systems, since it allows to predict drug release rates and to elucidate the physical transport mechanisms involved. In this paper we validate a novel mathematical model that describes progesterone(Prg) controlled release from poly-3-hydroxybutyric acid(PHB) membranes. A statistical analysis was conducted to compare the fitting of our model with six different models and the Akaike information criterion(AIC) was used to find the equation with best-fit. A simple relation between mass and drug released rate was found,which allows predicting the effect of Prg loads on the release behavior. Our proposed model was the one with minimum AIC value, and therefore it was the one that statistically fitted better the experimental data obtained for all the Prg loads tested. furthermore, the initial release rate was calculated and therefore, the interface mass transfer coefficient estimated and the equilibrium distribution constant of Prg between the PHB and the release medium was also determined. The results lead us to conclude that our proposed model is the one which best fits the experimental data and can be successfully used to describe Prg drug release in PHB membranes.

关键词： mathematical models model validation Drug delivery/release mass transfer coefficient Equilibrium distribution constant

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fluid flow simulation of industrial fixed bed mixed-flow grain dryer using k-ω SST turbulence model

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International Journal of Agricultural and Biological Engineering 2021年第2期14卷 226-230页

作者： Anderson Rodrigo Visconcini cid marcos Gonçalves Andrade Alexandre marconi de Souza Costa Post-graduation Department of mechanical Engineering University of MaringáAv.Colombo3790-Bloco 14-Sala 2487020-900Maringá-PRBrazil

The fluid dynamics analysis on industrial,mixed-flow grain dryers with fixed bed using computational techniques is necessary to assist the design of such equipment contributing to cost reduction in the dryer projects and agricultural drying operations that involve the production of grains in the *** study presents a Computational fluid Dynamic(CfD)solution for air flow analysis in an industrial *** air flow at the inlet and outlet of the dryer was investigated using the k-ωSST turbulence *** dryer region with soybean was considered as a laminar porous medium flow in the permanent and isothermal regime,having for the model a simplified geometry with the tower considered as a porous medium and the air inlet and outlet as a turbulent fluid *** flow was treated with a permanent and isothermal *** flow and pressures were used according to design *** validate the k-ωSST turbulence model,the velocity profile at the dryer inlet was obtained experimentally,which presented results with good agreement between the numerical and the experimental *** model obtained satisfactory results of the computational validation of the air flow in the dryer with good convergence requiring a minimum of computational effort,being suitable for the simulation of industrial-scale dryers,as to its air flow through a tower,operating with fixed bed soybean in the steady and isothermal regime.

关键词： computational methods fixed bed porous medium soybean dryer turbulent flow

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Numerical Solution for a Non-fickian Diffusion in a Periodic Potential

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Communications in Computational Physics 2013年第2期13卷 502-525页

作者： Adérito Araújo Amal K.Das cidália Neves Ercília Sousa CmUC Department of MathematicsUniversity of Coimbra3001-454 CoimbraPortugal Department of Physics DalhousieUniversityHalifaxNova Scotia B3H3J5Canada ISCAC Polytechnic Institute of Coimbra3040-316 CoimbraPortugal

Numerical solutions of a non-fickian diffusion equation belonging to a hyperbolic type are presented in one space *** Brownian particle modelled by this diffusion equation is subjected to a symmetric periodic potential whose spatial shape can be varied by a single *** consider a numerical method which consists of applying Laplace transform in time;we then obtain an elliptic diffusion equation which is discretized using a finite difference *** analyze some aspects of the convergence of the *** results for particle density,flux and mean-square-displacement(covering both inertial and diffusive regimes)are presented.

关键词： Numerical methods Laplace transform telegraph equation periodic potential non-fickian diffusion

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Daily expression of sodium-dependent glucose cotransporter-1protein in jejunum during rat ontogeny

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Animal Nutrition 2019年第3期5卷 290-296页

作者： Juan I.Baston fabricio D.cid Enrique Caviedes-vida. Juan G.Chediack Laboratorio de fisiopatología Endometrial Instituto de Biología y Medicina Experimental(IByME)CONICETCiudad Autoonoma de Buenos AiresC1428ADNArgentina Laboratorio de Biología Integrativa“Prof.E.Caviedes Codelia” Facultad de QuímicaBioquímica y FarmaciaUniversidad Nacional de San LuisSan LuisD5700HHWArgentina Instituto multidisciplinario de Investigaciones en Biología-San Luis(ImIBIO-SL CCT-SL)CONICETSan Luis D5700HHWArgentina

It is widely known that intestinal capacities such as the enzymatic hydrolysis of carbohydrates,lipids and proteins,and the subsequent absorption of the hydrolyzed *** evolutionary matched to dietary loads and feeding *** this study,we demonstrate that the protein expression of apically located sodium-dependent glucose cotransporter-1(SGLT-1)throughout rat ontogeny is daily adjusted to afford glucose uptake when the load of this metabolically essential monosaccharide in the intestinal lumen is *** jejunal expression of SGLT-1 protein in 14 one-day-old suckling pups was found to increase at dark and early light phase(Pmother *** weaning21-d-old and juvenile 28-d-old rats,the cotransporter expression was high throughout the entire day(Pfinally,adult 90-d-old rats showed a well-developed circadian rhythm for SGLT-1 protein(Pxpression increased at late light and dark phase when the highest intestinal glucose load was *** our knowledge,these results are the first reporting the daily profile of SGLT-1 expression during rat early developmental stage and may contribute to understand the biological significance of a well-established molecular capacity to deal with the crucial increase of glucose load in the diet during the weaning process.

关键词： Intestinal SGLT-1 Protein expression Daily rhythms Ontogeny Rat

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Synthesis of activated carbons from black sapote seeds,characterization and application in the elimination of heavy metals and textile dyes

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Chinese Journal of Chemical Engineering 2020年第2期28卷 613-623页

作者： Alejandra Alicia Peláez-cid Vincent Romero-Hernández Ana maría Herrera-González Alejandro Bautista-Hernández Oscar Coreno-Alonso facultad de Ingeniería Benemérita Universidad Autónoma de PueblaMexico Instituto de Ciencias Básicas e Ingeniería Universidad Autónoma del Estado de HidalgoMexico División de Ingenierías Universidad de GuanajuatoMexico

many different techniques may be used to remove industrial pollutants from wastewater. Adsorption using activated carbon has been reported to be an effective method. This work proposes the use of a vegetable residue(black sapote seeds) as a raw material for its synthesis. These carbons were chemically activated using phosphoric acid and carbonized at 673 and 873 K. Adsorption isotherms were constructed for the textile dyes on the carbons, and this data was treated using Langmuir’s equation to quantitatively describe the adsorption process. The synthesized carbons were characterized using fTIR, EA, SEm, Nitrogen adsorption(specific surface areas of 879 and 652 m2·g-1), and their points of zero charge(2.1 and 2.3). It was possible to adsorb both heavy metals and textile dyes present in aqueous solutions and wastewaters using these activated carbons. Heavy metals were adsorbed almost completely by both carbons. Cationic dyes where adsorbed(58–59.8 mg·g-1) in greater amounts compared to anionic dyes(10–58.8 mg·g-1). The amount of anionic dyes adsorbed increased almost 30% by changing the pH of the solutions. One of the carbons was thermally regenerated on three occasions without losing its adsorption capacity and it was proved in a flow system.

关键词： Activated carbons Black sapote seeds Heavy metal adsorption Textile dye adsorption Wastewater treatment

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Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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Journal of Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： S.Pérez-Rodríguez m.Gutiérrez-Roa C.Giménez-Rubio D.Ríos-Ruiz P.Arévalo-cid m.V.martínez-Huerta A.Zitolo m.J.Lázaro D.Sebastián Instituto de Carboquímica(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y Petroleoquímica(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. for comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 m KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide

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Hypothalamic circuits and aging:keeping the circadian clock updated

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Neural Regeneration Research 2024年第9期19卷 1919-1928页

作者： Rosa Vázquez-Lizarraga Lucia mendoza-Viveros Carolina cid-Castro Sareni Ruiz-montoya Erick Carreño-Vázquez Ricardo Orozco-Solis Instituto Nacional de medicina Genómica(INmEGEN) México CityMéxico Centro de Investigacíon sobre el Envejecimiento Centro de Investigacíon y de Estudios Avanzados(CIE-CINVESTAV)México CityMéxico Instituto de Investigaciones Biomédicas Universidad Nacional Autónoma de México UNAMMéxico CityMéxico

Over the past century,age-related diseases,such as cancer,type-2 diabetes,obesity,and mental illness,have shown a significant increase,negatively impacting overall quality of *** on aged animal models have unveiled a progressive discoordination at multiple regulatory levels,including transcriptional,translational,and post-translational processes,resulting from cellular stress and circadian *** circadian clock emerges as a key regulator,sustaining physiological homeostasis and promoting healthy aging through timely molecular coordination of pivotal cellular processes,such as stem-cell function,cellular stress responses,and inter-tissue communication,which become disrupted during *** the crucial role of hypothalamic circuits in regulating organismal physiology,metabolic control,sleep homeostasis,and circadian rhythms,and their dependence on these processes,strategies aimed at enhancing hypothalamic and circadian function,including pharmacological and non-pharmacological approaches,offer systemic benefits for healthy *** brain-directed drug administration represents a promising avenue for effectively targeting specific brain regions,like the hypothalamus,while reducing side effects associated with systemic drug delivery,thereby presenting new therapeutic possibilities for diverse age-related conditions.

关键词： aging astrocytes cellular stress responses circadian clock hypothalamus intranasal drug administration metabolic control nutrient sensor SIRT1 sleep homeostasis

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fecal immunochemical test accuracy in average-risk colorectal cancer screening

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World Journal of Gastroenterology 2014年第4期20卷 1038-1047页

作者： Vicent Hernandez Joaquin Cubiella m Carmen Gonzalez-mao felipe Iglesias Concepción Rivera m Begoa Iglesias Lucía cid Ines Castro Luisa de Castro Pablo Vega Jose Antonio Hermo Ramiro macenlle Alfonso martínez-Turnes David martínez-Ares Pamela Estevez Estela cid m Carmen vida. Angeles López-martínez Elisabeth Hijona marta Herreros-Villanueva Luis Bujanda Jose Ignacio Rodriguez-Prada the COLONPREV study investigators Department of Gastroenterology Complexo Hospitalario Universitario de Vigo Department of Gastroenterology Complexo Hospitalario Universitario de Ourense Department of Clinical Analysis Complexo Hospitalario Universitario de Vigo Department of Pathology Complexo Hospitalario Universitario de Vigo Department of Gastroenterology Donostia Hospital Biodonostia Institute University of the Basque Country UPV/EHU

AIm: To assess the fecal immunochemical test (fIT) accuracy for colorectal cancer (CRC) and advanced neoplasia (AN) detection in CRC screening.

关键词： Colorectal neoplasms Early detection of cancer Sensitivity and specificity Adenoma Occult blood Cost-benefit analysis

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