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Use of two-surfactants mixtures to attain specific HLB values for assisted TPH-diesel biodegradation

Journal of Environmental Sciences 2004年第6期16卷 950-956页

作者： luis G. Torres Neftalí Rojas Rosario Iturbe Instituto de Ingeniería Universidad Nacional Autó noma de México Coordinación de Ingeniería Ambiental Grupo Saneamiento de Suelos y Acuíferos Apartado Postal 70-472 Coyoacán 04510 México D.F. Mexico

In a surfactant assisted biodegradation process, the choice of surfactant(s) is of crucial importance. The question is: does the type of surfactant(i.e. chemical family) affect the biodegradation process at fixed hidrophillic-lypofillic balance(HLB) values? Microcosm assessments were developed using contaminated soil, with around of 5000 mg/kg of hydrocarbons as TPH-diesel. Mixtures of three nonionic surfactants were employed to get a wide range of specific HLB values. Tween20 and Span20 were mixed in the appropriate proportions to get HLB values between 8.6 and 16.7. Tween/Span60 mixtures reached HLB values between 4.7 and 14.9. Finally, Tween/Span80 combinations yielded HLB values between 4.3 and 15. TPH-diesel biodegradation was measured at the beginning, and after 8 weeks, as well as the FCU/gr soil, as a measure of microorganisms′ development during the biodegradation period. A second aim of this work was to assess the use of guar gum as a biodegradation enhancer instead of synthetic products. The conclusions of this work are that surfactant chemical family, and not only the HLB value clearly affects the assisted biodegradation rate. Surfactant's synergism was clearly observed. Regarding the use of guar gum, no biodegradation enhancement was observed for the three assessed concentrations, i.e., 2, 20, and 200 mg/kg, respectively. On the contrary, TPH-diesel removal was lower as the gum concentration increased. It is quite possible that guar gum was used as a microbial substrate.

关键词： aged soils enhanced bioremediation HLB mixtures Tween Span surfactants

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Multiple intrahepatic pseudocysts in acute pancreatitis

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World Journal of Gastroenterology 2007年第34期13卷 4655-4657页

作者： David Casado luis Sabater Julio Calvete Empar Mayordomo luis Aparisi Juan Sastre Salvador Lledo Department of Surgery Liver Biliary and Pancreatic Unit University of Valencia Spain Department of Pathology University of Valencia Spain Laboratory of Pancreatic Function Hospital Clinic University of Valencia Spain Department of Physiology University of Valencia Spain

Liver pseudocysts are a very rare complication in acute pancreatitis with only a few cases previously described. The lack of experience and literature on this condition leads to difficulties in the differential diagnosis and management. We report herein a case of acute pancreatitis who developed multiple intrahepatic pseudocysts. After complete imaging evaluation, the diagnosis was still unclear and the patient was operated on. The presence of liver lesions in patients with acute pancreatitis should raise the possibility of intrahepatic pseudocysts.

关键词： Pancreatic pseudocyst Liver pseudocyst Intrahepatic pseudocyst

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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

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Adding fifth dimension to optoacoustic imaging: volumetric time-resolved spectrally enriched tomography

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Light(Science & Applications) 2014年第1期3卷 330-334页

作者： Xose luis Dean-Ben Daniel Razansky Institute for Biological and Medical Imaging(IBMI) Technical University of Munich and Helmholtz Center Munich85764 NeuherbergGermany

Optoacoustics provides a unique set of capabilities for bioimaging,associated with the intrinsic combination of ultrasound-and light-related advantages,such as high spatial and temporal resolution as well as powerful spectrally enriched imaging contrast in biological *** demonstrate here,for the first time,the acquisition,processing and visualization of five-dimensional optoacoustic data,thus offering unparallel imaging capacities among the current bioimaging *** newly discovered performance is enabled by simultaneous volumetric detection and processing of multispectral data and is further showcased here by attaining time-resolved volumetric blood oxygenation maps in deep human vessels and real-time tracking of contrast agent distribution in a murine model in vivo.

关键词： biophotonics multispectral optoacoustic imaging photoacoustic tomography

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Symmetrization for Fractional Elliptic and Parabolic Equations and an Isoperimetric Application(Dedicated to Haim Brezis,great master of analysis,on his 70th birthday)

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Chinese Annals of Mathematics,Series B 2017年第2期38卷 661-686页

作者： Yannick SIRE Juan luis VAZQUEZ Bruno VOLZONE johns hopkins university Krieger Hall3401 N.Charles StBaltimoreM D21218USA. departamento de matemticas universidad autnoma de madrid28049 M adridSpain dipartimento di ingegneria universit degli studi di napoli"parthenope"80143 Italia.

This paper develops further the theory of symmetrization of fractional Laplacian operators contained in recent works of two of the authors. This theory leads to optimal estimates in the form of concentration comparison inequalities for both elliptic and parabolic equations. The authors extend the theory for the so-called restricted fractional Laplacian defined on a bounded domain Ω of R^N with zero Dirichlet conditions outside of Ω. As an application, an original proof of the corresponding fractional Faber-Krahn inequality is derived. A more classical variational proof of the inequality is also provided.

关键词： Symmetrization, Fractional Laplacian, Nonlocal elliptic and parabolicequations, Faber-Krahn inequality

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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

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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

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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

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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

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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

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