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Glyphosate Dissipation in Different Soils Under No-Till and Conventional Tillage

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Pedosphere 2019年第6期29卷 773-783页

作者： Elena OKADA Joséluis COSTA Francisco BEDMAR Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Balcarce 7620(Argentina Estación Experimental Agropecuaria Balcarce Instituto Nacional de Tecnología Agropecuaria(INTA)Balcarce 7620(Argentina Facultad de Ciencias Agrarias Universidad Nacional de Mar del PlataBalcarce 7620(Argentina

Glyphosate is the most used herbicide in Argentina, accounting for 62% of the commercialized pesticides on the market. It is used as a weed controller in no-till systems, and it is also applied to various genetically modified crops ( e.g., soybean, corn, and cotton). Although it has a high solubility in water, it tends to adsorb and accumulate in agricultural soils. The main objectives of this work were to compare the dissipation of glyphosate and the accumulation of its metabolite aminomethylphosphonic acid (AMPA) over time in three soils from agricultural areas of Argentina under long-term management with no-till (NT) and conventional tillage (CT) practices. There were no differences in dissipation between NT and CT, indicating that the glyphosate-degrading microflora was not modified by the different tillage managements. Moreover, tillage practices did not alter the general soil properties;therefore, glyphosate bioavailability was not affected by NT or CT practice. Forty percent of the applied glyphosate was degraded within the first three days in all soils, indicating a fast initial dissipation rate. However, the dissipation rate considerably decreased over time, and the degradation kinetics followed a bi-exponential (or two-compartment) kinetic model. No differences were found between tillage practices. Dissipation was not related to the microbial activity measured as soil respiration. The fast decrease in the concentration of glyphosate at the beginning of the dissipation study was not reflected in an increase in the concentration of AMPA. The estimated half-lives for glyphosate ranged between 9 and 38 d. However, glyphosate bioavailability decreases over time, as it is strongly adsorbed to the soil matrix. This increases its residence time, which may lead to its accumulation in agricultural soils.

关键词： Aminomethylphosphonic acid Bioavailability Biodegradation Herbicide Metabolite Pesticide Two-compartment kinetic model

Magnetofection as a new tool to study microglia biology

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Neural Regeneration Research 2019年第5期14卷 767-768页

作者： Jose luis Venero Miguel Angel Burguillos Instituto de Biomedicina de Sevilla (IBiS)/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla and Departamento de Bioquímica y Biología Molecular Facultad de Farmacia Universidad de Sevilla Department of Biochemistry University of Cambridge

Microglia are the resident macrophages of the brain,originally described by Pio del Rio-Hortega(a student of Santiago Ramon y Cajal)in a series of studies in *** those pioneering studies,many others have followed to describe microglia as complex and multitasking cells with many diverse roles under physiological(*** key role in synapse pruning during development)or diseased *** exist as sentinels or surveyors of the environment that surround neurons,becoming reactive upon a wide array of stimuli and consequently developing an appropriate inflammatory *** fact,a neuroinflammatory response driven by microglia is found in virtually every disease process that occurs within the central nervous ***,a better understanding of the mechanisms governing the microglia response is the key to improving the outcome of neurodegenerative conditions.

关键词： Magnetofection new tool study microglia biology

Perpendicularly Self-Oriented and Shape-Controlled L10-FePt Nanorods Directly Synthesized by a Temperature-Modulated Process

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Nano Research 2011年第7期4卷 666-674页

作者： Tiago luis da Silva Laudemir Carlos Varanda Colloidal Materials Group Instituto de Quimica de Sao Carlos Universidade de Sao Paulo--USP Sao Carlos PO Box 780 13566-590 Brazil

The synthesis and self-assembly of tetragonal phase-containing L10-Fe55Pt45 nanorods with high coercive field is described. The experimental procedure resulted in a tetragonal/cubic phase ratio close to 1：1 for the as-synthesized nanoparticles. Using different surfactant/solvent proportions in the process allowed control of particle morphology from nanospheres to nanowires. Monodisperse nanorods with lengths of 60 ＋ 5 nm and diameters of 2-3 nm were self-assembled in a perpendicular oriented array onto a substrate surface using hexadecylamine as organic spacer. Magnetic alignment and properties assigned, respectively, to the shape anisotropy and the tetragonal phase suggest that the self-assembled materials are a strong candidate to solve the problem of random magnetic alignment observed in FePt nanospheres leading to applications in ultrahigh magnetic recording （UHMR） systems capable of achieving a performance of the order of terabits/in2.

关键词： Magnetic materials data storage FePt nanorods self-assembl~ perpendicular magnetic alignment

Slope reliability and back analysis of failure with geotechnical parameters estimated using Bayesian inference

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第3期11卷 628-643页

作者： luis-Fernando Contreras Edwin T.Brown The University of Queensland St Lucia Campus

A Bayesian approach is proposed for the inference of the geotechnical parameters used in slope *** methodology involves the construction of posterior probability distributions that combine prior information on the parameter values with typical data from laboratory tests and site investigations used in *** posterior distributions are often complex,multidimensional functions whose analysis requires the use of Markov chain Monte Carlo(MCMC)*** procedures are used to draw representative samples of the parameters investigated,providing information on their best estimate values,variability and *** paper describes the methodology to define the posterior distributions of the input parameters for slope design and the use of these results for evaluation of the reliability of a slope with the first order reliability method(FORM).The reliability analysis corresponds to a forward stability analysis of the slope where the factor of safety(FS)is calculated with a surrogate model from the more likely values of the input *** Bayesian model is also used to update the estimation of the input parameters based on the back analysis of slope *** this case,the condition FS?1 is treated as a data point that is compared with the model prediction of *** analysis requires a sufficient number of observations of failure to outbalance the effect of the initial input *** parameters are updated according to their uncertainty,which is determined by the amount of data supporting *** methodology is illustrated with an example of a rock slope characterised with a Hoek-Brown rock mass *** example is used to highlight the advantages of using Bayesian methods for the slope reliability analysis and to show the effects of data support on the results of the updating process from back analysis of failure.

关键词： Bayesian analysis Hoek-Brown criterion Slope reliability Back analysis of failure

Black holes in asymptotic safety with higher derivatives:accretion and stability analysis

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Chinese Physics C 2021年第7期45卷 293-304页

作者： Fabian H.Zuluaga luis A.Sanchez Escuela de Fisica Universidad Nacional de ColombiaA.A.3840MedellinColombia

We review steady spherically symmetric accretion onto a renormalization group improved Schwarzschild space-time,which is a solution to an asymptotically safe theory(AS)containing high-derivative *** use a Hamiltonian dynamical system approach for the analysis of the accretion of four types of isothermal test fluids:ultra-stiff fluid,ultra-relativistic fluid,radiation fluid,and sub-relativistic *** important outcome of our study is that,contrary to the claim in a recent work,there are physical solutions for the accretion of an ultra-relativistic fluid in AS,which include subsonic,supersonic,and transonic ***,we study quantum corrections to the known stability of the accretion in general relativity(GR).To this end,we use a perturbative procedure based on the continuity equation with the mass accretion rate being the perturbed *** classes of perturbations are studied:standing and traveling *** find that quantum gravity effects either enhance or diminish the stability of the accretion depending on the type of test fluid and the radial distance to the central object.

关键词： asymptotic safety black holes accretion stability

Occurrence data may provide unreliable thermal preferences and breadth of species

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Current Zoology 2015年第6期61卷 972-982页

作者： Sara VILLEN-PEREZ luis M. CARRASCAL Department of Biogeography and Global Change National Museum of Natural Sciences MNCN-CSIC. C/José Gutiérrez Abascal 2 28006 Madrid Spain.

Accurate information on the thermal preference and specialization of species is needed to understand and predict spe- cies geographical range size and vulnerability to climate change. Here we estimate the position and breadth of species within thermal gradients based on the shape of the response curve of species abundance to temperature. The objective of the study is to compare the measurements of this approach based on abundance data with those of the classical approach using species＇ occur- rence data. The relationship between species＇ relative abundance and minimum winter temperature of 106 bird species wintering in the Iberian Peninsula is modeled at 100 Km2 resolution with quadratic logistic regressions. From these models we calculated the preferred temperature of species as the temperature at which the abundance is maximized, and the thermal breadth of species as the relative area under the temperature-abundance curve. We also estimated the thermal preferences and breadth of species as the average temperature and temperature range of the UTM cells in which the species are present. The abundance-temperature response curves reveal that birds prefer higher temperatures to overwinter, and are more thermally selective, than is measured by the classical approach. Moreover, response curves detect a higher inter-specific variability in both thermal preferences and ther- mal breadth of species. As occurrence data gives the same weight to cells with one or many individuals, the average temperature of the cells in which the species is present roughly reflects the average temperature in the region of study and not the environ- mental preferences of species .

关键词： Abundance-temperature response curve Birds Species occurrence Thermal breadth Thermal preferences Winter

Woodland Mediterranean birds can resist a dry extreme cold wave

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Current Zoology 2014年第4期60卷 429-437页

作者： Sara VILLEN-PEREZ luis M. CARRASCAL Department of Biogeography and Global Change Museo Nacional de Ciencias Naturales (CSIC) C/Jos6 Guti6rrez Abascal 228006 Madrid Spain

The ecological consequences of climate extreme events are still poorly understood, especially those related to cold episodes. Winter cold spells might imperil the energy balance of small passerines, thus compromising their survivorship. Here we analyze how the abundance and habitat use of three tree-gleaning passerine species wintering in a montane oakwood of central Spain at ca. 1,300 m a.s.1, was influenced by the cold wave that hit Europe in February 2012. We monitored temperature, wind and the relative abundance of great tit Parus major, blue tit Cyanistes caeruleus and long-tailed tit Aegithalos caudatus in 15 plots throughout three periods： before, during and after the cold wave. Our results clearly rule out widespread mortality and temporal migration of the studied passerine populations, as the abundance of these species did not diminish during the cold wave. Moreover, the species usually foraging higher in the tree canopy -and thus more exposed to windmoved to the less windy woodland plots （long-tailed tit） and reduced their foraging height above ground during the cold wave （long-tailed tit and blue tit）, probably to mitigate the deleterious effects of wind chill. Therefore, these forest birds were able to cope with a dry cold wave that was statistically extreme in terms of temperature and wind chill, according to the historic climate records of the region. It seems that, at least when foraging substrates are not heavily covered by snow or ice, Mediterranean birds can resist an extreme cold wave [Current Zoology 60 （4）： 429-437, 2014].

关键词： Cold wave Harsh weather Mediterranean oakwoods Temperature Tree-gleaning birds Wind chill

Risk factors for acute kidney injury after partial hepatectomy

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World Journal of Hepatology 2017年第18期9卷 815-822页

作者： luis Cesar Bredt luis Alberto Batista Peres Department of Surgical Oncology and Hepa- tobiliary Surgery University Hospital of Western Paraná State University of Western Paraná Department of Nephrology University Hospital of Western Paraná State University of Western Paraná

To identify risk factors for the occurrence of acute kidney injury (AKI) in the postoperative period of partial hepatectomies. METHODSRetrospective analysis of 446 consecutive resections in 405 patients, analyzing clinical characteristics, preoperative laboratory data, intraoperative data, and postoperative laboratory data and clinical evolution. Adopting the International Club of Ascites criteria for the definition of AKI, potential predictors of AKI by logistic regression were identified. RESULTSOf the total 446 partial liver resections, postoperative AKI occurred in 80 cases (17.9%). Identified predictors of AKI were: Non-dialytic chronic kidney injury (CKI), biliary obstruction, the Model for End-Stage Liver Disease (MELD) score, the extent of hepatic resection, the occurrence of intraoperative hemodynamic instability, post-hepatectomy haemorrhage, and postoperative sepsis. CONCLUSIONThe MELD score, the presence of non-dialytic CKI and biliary obstruction in the preoperative period, and perioperative hemodynamics instability, bleeding, and sepsis are risk factors for the occurrence of AKI in patients that underwent partial hepatectomy.

关键词： Kidney injury Hepatectomy Postoperative Liver Resection

Methylation of DAPK and THBS1 genes in esophageal gastric-type columnar metaplasia

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World Journal of Gastroenterology 2016年第18期22卷 4567-4575页

作者： Roberto Herrera-Goepfert luis F Onate-Ocana José luis Mosqueda-Vargas luis A Herrera Clementina Castro Julia Mendoza Rodrigo González-Barrios Department of Pathology Instituto Nacional de Cancerologia (INCan) 10480 Mexico DF Mexico Clinical Research Division Instituto Nacional de Cancerologia (INCan) 10480 Mexico DF Mexico Unidad de Investigacion Biomedica en Cancer Instituto Nacional de Cancerologia (INCan)-Instituto de Investigaciones Biomedicas (IIB) Universidad Nacional Autonoma de Mexico (UNAM) 14080 Mexico DF Mexico

AIM: To explore methylation of DAPK, THBS1, CDH-1, and p14 genes, and Helicobacter pylori(H. pylori) status in individuals harboring esophageal columnar ***: Distal esophageal mucosal samples obtained by endoscopy and histologically diagnosed as gastric-type(non-specialized) columnar metaplasia, were studied thoroughly. DNA was extracted from paraffin blocks, and methylation status of deathassociated protein kinase(DAPK), thrombospondin-1(THBS1), cadherin-1(CDH1), and p14 genes, was examined using a methyl-sensitive polymerase chain reaction(MS-PCR) and sodium bisulfite modification protocol. H. pylori cag A status was determined by ***: In total, 68 subjects(33 females and 35 males), with a mean age of 52 years, were included. H. pylori cag A positive was present in the esophageal gastric-type metaplastic mucosa of 18 individuals. DAPK, THSB1, CDH1, and p14 gene promoters were methylated by MS-PCR in 40(58.8%), 33(48.5%), 46(67.6%), and 23(33.8%) cases of the 68 esophageal samples. H. pyloristatus was associated with methylation of DAPK(P = 0.003) and THBS1(P = 0.019).CONCLUSION: DNA methylation occurs in cases of gastric-type(non-specialized) columnar metaplasia of the esophagus, and this modification is associated with H. pylori cag A positive infection.

关键词： DNA methylation Esophageal columnar metaplasia Thrombospondin-1 Death-associated protein kinase Helicobacter pylori cagA