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Chromium Adsorption in Different Mineralogical Fractions from Subtropical Soils

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Pedosphere 2017年第1期27卷 106-111页

作者： Jovana BAVArESCO Jesse r. FINK Maria Lucia K. rODrIGUES Clesio GIANELLO Vidal BArrON jose TOrrENT Department of Soils Federal University of Rio Grande do Sul 91540-000 Porto Alegre Rio Grande do Sul (Brazil) Laboratory of Soils Federal Institute of Parand 85555-000 Palmas Parand (Brazil) Department of research and Laboratory Environmental Protection Foundation of Rio Grande do Sul State 90620-090 Porto AlegreRio Grande do Sul (Brazil) Department of Agronomy University of Cdrdoba C4 Building Campus of Rabanales 14071 C6rdoba (Spain)

Safe application of chromium （Cr）-containing organic industrial wastes to soil requires considering the ability of the soil to adsorb Cr. In this study, the maximum Cr adsorption capacity was assessed for the bulk samples and their clay and iron-free clay fractions of four subtropical soils differing in mineralogy. To this end, the samples were supplied with Cr（Ⅲ） nitrate solutions at pH 4.5 or 5.5. The results of Cr（Ⅲ） adsorption fitted to a Freundlich equation and the adsorption capacity was positively correlated with soil organic matter and iron oxide contents. The clay fractions adsorbed more Cr per unit mass than the bulk soils and the iron-free clay fractions. The Cr（Ⅲ） adsorption capacity increased with increasing soil pH due to more charges on adsorbing surfaces. Our results suggest that the soils rich in organic matter and iron oxides and having a pH above 4.5 are suitable for application of Cr（Ⅲ）-loaded industrial wastes.

关键词： adsorption capacity environmental contamination iron-free clay fractions iron oxides point of zero charge specificsurface area

Analysis and Validation for an Inverter-side Current Controller in LCL Grid-connected Power Systems

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Journal of Modern Power Systems and Clean Energy 2020年第2期8卷 387-398页

作者： jose MSosa Panfilo r.Martinez-rodriguez Gerardo Escobar Gerardo Vazquez Andres A.Valdez-Fernandez Juan F.Martinez-Garcia the Tecnologico Nacional de Mexico/ITS de Irapuato(TecNM/ITESI) IrapuatoGTO 36821Mexico the School of Sciences Autonomous University of San Luis Potosi(UASLP)San Luis PotosiSLP 78290Mexico Tecnologico de Monterrey N.L.64849Mexico

Transformerless grid-connected inverters offer greater efficiencies when transferring power from renewable energy sources to the electrical *** the grid-inverter connection is done with an LCL filter,high attenuation of switching harmonics is achieved while preserving a small-size output ***,damping must be included in the controller to assure closed-loop *** paper proposes a reference computation methodology for the inverter-side current feedback in a photovoltaic(PV)generation system connected to the grid through an LCL *** analysis of the closed-loop system stability and of the steady-state performance are presented as well as experimental validation of the closed-loop *** feedback controller includes active damping and relies on a resonant control structure which improves the ability of dealing with grid harmonic *** controller uses a reduced set of measurements,which requires the inverter-side current and grid voltage only,and assures a power factor close to unity.

关键词： LCL filter transformerless inverter grid connection inverter-side current feedback

Efficacy and safety of Chlorella supplementation in adults with chronic hepatitis C virus infection

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World Journal of Gastroenterology 2013年第7期19卷 1085-1090页

作者： jose Azocar Arley Diaz Northgate Medical Center SpringfieldMA01103United States

AIM:To evaluate the safety and efficacy of Chlorella in 18 patients chronically infected with hepatitis C virus(HCV) genotype ***:Eighteen adults with chronic infection by HCV genotype 1 received daily oral supplementation of Chlorella for 12 *** in the rNA levels of HCV,as well as those of aspartate aminotransferase(AST) and alanine aminotransferase(ALT) levels were evaluated following this treatment *** t tests were conducted to compare the means of the different variables at the beginning and end of the *** effects and quality of life aspects were also compared between weeks 0 and 12 of the study ***:A majority 84.61% of the patients had a significant decrease in their ALT levels from week 0 to week *** of side effects showed that Chlorella was well *** of life assessment showed that 76.9 of the participants reported an improvement in their energy levels and 46.1% reported an improvement in their perception of general *** 69.23% also showed a decrease in their AST levels,this was not statistically *** patients that exhibited an improvement in their ALT and AST levels also showed a tendency toward a decreased HCV viral *** HCV rNA levels showed a decrease in 69.23% of the patients,which along with changes in AST/ALT ratios from week 0 to week 12,these results were not statistically ***:Chlorella supplementation was well tolerated in patients with chronic HCV and associated with a significant decrease in ALT liver enzyme levels.

关键词： Chlorella Hepatitis C virus Interferon Aspartate and alanine aminotransferase ratio

An Invasive Succulent Plant (Kalanchoe daigremontiana) Influences Soil Carbon and Nitrogen Mineralization in a Neotropical Semiarid Zone

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Pedosphere 2018年第4期28卷 632-643页

作者： Ileana HErrErA jose r. FErrEr-PArIS Diana BENZO Saul FLOrES Belkis GArCIA Jafet M. NASSAr Ecuela de Ciencias Ambientales Universidad Espiritu Santo Guayaquil 091650 (Ecuador) Centro de Ecologla Instituto Venezolano de Investigaciones Cientificas (IVIC) Caracas 1020 (Venezuela) Centro de Estudios Botdnieos y Agroforestales Instituto Venezolano de Investigaeiones Cientificas Maracaibo 4005 (Venezuela)

It has long been recognized that plant invasions may alter carbon （C） and nitrogen （N） cycles, but the direction and magnitude of such alterations have been rarely quantified. In this study, we quantified the effects caused by the invasion of a noxious exotic plant, Kalanchoe daigrernontiana （Crassulaceae）, on C and N mineralization and enzymatic and microbial activities in the soil of a semiarid locality in Venezuela. We compared soil parameters associated with these processes （C and N mineralization time and the cumulative values, fluorescein diacetate hydrolytic activity, and activities of dehydrogenase, β-glucosidase, glucosaminidase, and urease） between invaded and adjacent non-invaded sites. In addition, correlations among these parameters and the soil physical-chemical properties were also examined to determine if a positive feedback exists between nutrient availability and K. daigremontiana invasion. Overall, our results showed that C mineralization and transformation of organic compounds to NH4^＋ were favored at sites colonized by K. daigrernontiana. With this species, we found the highest cumulative amounts of NH4^＋-N and C and the lowest mineralization time. These results could be explained by higher activities of urease and glueosaminidase in soils under the influence of K. daigremontiana. In addition, higher amounts of organic matter and moisture content in invaded soils might favor C and N mineralization. In conclusion, invasion of Neotropical semiarid zones by K. daigrernontiana may influence the chemical and biological properties of the soils covered by this species, increasing nutrient bioavailability, which, in time, can facilitate the invasion process.

关键词： Akaike Information Criterion C and N pools enzymatic activity NH4^+-N NO3^--N nutrient availability plant invasion

The Effect of Laser Ablation Pulse Width and Feed Speed on Necrosis and Surface Damage of Cortical Bone

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Chinese Journal of Mechanical Engineering 2022年第3期35卷 106-122页

作者： jose A.robles‑Linares Kieran Winter Zhirong Liao Faculty of Engineering University of NottinghamNottingham NG72RDUK

Bone cutting is of importance in orthopaedic surgery but is also challenging due to its nature of brittleness—where severe mechanical and thermal damages can be introduced easily in conventional *** machining is a new technology that can allow for complex cut geometries whilst minimising surface defects i.e.,smearing,which occur in mechanical ***,comparative studies on the influence of lasers with different pulse characteristics on necrotic damage and surface integrity have not been reported *** paper for the first time investigates the effects of laser type on the necrotic damage and surface integrity in fresh bovine cortical bone after ex-situ laser *** lasers of different pulse widths,i.e.,picosecond,nanosecond and continuous wave lasers have been investigated with different feed speeds tested to study the machining *** cutting temperature,and geometrical outputs have been measured to investigate the thermal influence on the cooling behaviour of the bone samples while high-speed imaging was used to compare the material removal mechanisms between a pulsed and continuous wave ***,an in-depth histological analysis of the subsurface has revealed that the nanosecond laser caused the largest necrotic depth,owing to the high pulse frequency limiting the dissipation of *** has also been observed that surface cracks positioned perpendicular to the trench direction were produced after machining by the picosecond laser,indicative of the photomechanical effect induced by plasma ***,the choice of laser type(i.e.,in terms of its pulse width and frequency)needs to be critically considered for appropriate application during laser osteotomy with minimum damage and improved healing.

关键词： Bone cutting Necrosis Surface damage Laser machining Histology

Structural performance assessment of GFrP elastic gridshells by machine learning interpretability methods

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Frontiers of Structural and Civil Engineering 2022年第10期16卷 1249-1266页

作者： Soheila KOOKALANI Bin CHENG jose Luis Chavez TOrrES Department of Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Civil Engineering Technical University of LojaLoja 110102Ecuador

The prediction of structural performance plays a significant role in damage assessment of glass fiber reinforcement polymer(GFrP)elastic gridshell *** learning(ML)approaches are implemented in this study,to predict maximum stress and displacement of GFrP elastic gridshell *** ML algorithms,including linear regression(Lr),ridge regression(rr),support vector regression(SVr),K-nearest neighbors(KNN),decision tree(DT),random forest(rF),adaptive boosting(AdaBoost),extreme gradient boosting(XGBoost),category boosting(CatBoost),and light gradient boosting machine(LightGBM),are implemented in this *** features of structural performance considered in this study are the maximum stress as f1(x)and the maximum displacement to self-weight ratio as f2(x).A comparative study is conducted and the Catboost model presents the highest prediction ***,interpretable ML approaches,including shapely additive explanations(SHAP),partial dependence plot(PDP),and accumulated local effects(ALE),are applied to explain the *** is employed to describe the importance of each variable to structural performance both locally and *** results of sensitivity analysis(SA),feature importance of the CatBoost model and SHAP approach indicate the same parameters as the most significant variables for f1(x)and f2(x).

关键词： machine learning gridshell structure regression sensitivity analysis interpretability methods

Invasive-invaded system of non-Lipschitz porous medium equations with advection

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International Journal of Biomathematics 2021年第7期14卷 299-327页

作者： jose Luis Diaz Palencia Escuela Politecnica Superior Universidad Francisco de Vitoria Ctra.Pozuelo-Majadahonda Km 1 80028223Pozuelo de AlarconMadrid

This work provides analytical results towards applications in the field of invasive-invaded systems modeled with nonlinear diffusion and with *** results focus on showing regularity,existence and uniqueness of weak solutions using the condition of a nonlinear slightly positive parabolic operator and the reaction-absorption monotone *** coupling in the reaction-absorption terms,that characterizes the species interaction,impedes the formulation of a global comparison principle that is shown to exist ***,this work provides analytical solutions obtained as selfsimilar minimal and maximal profiles.A propagating diffusive front is shown to exist until the invaded specie notes the existence of the *** the desertion of the invaded st arts,the diffusive front vanishes globally and the nonlinear diffusion concentrates only on the propagating tail which exhibits finite ***,the invaded specie is shown to exhibit an exponential decay along a characteristic *** exponential decay is not trivial in the nonlinear diffusion case and confirms that the invasive continues to feed on the invaded during the desertion.

关键词： Nonlinearity reaction absorption coupled system diffusion porous media

Methanol extract of Desmodium gangeticum DC root mimetic post-conditioning effect in isolated perfused rat heart by stimulating muscarinic receptors

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Asian Pacific Journal of Tropical Medicine 2012年第6期5卷 448-454页

作者： Gino A Kurian jose Paddikkala Medical Biochemistry School of Chemical and BiotechnologySASTRA UniversityThirumalaisamudramThanjavurTamil NaduIndiaPin:613402 Department of Plant Biotechnology Amala Cancer Research CenterAmalanagarTrichurKeralaIndia

Objective:To evaluate pharmacological mimetic action of herbal extract Desmodium gangeticum (DC) roots on ischemia reperfusion ***:With the help of Langendroff perfusion technique,ischemic post condition(POC) mimetic action of DG methanol root extract was evaluated and compared by using standard drugs that acts as muscarinic receptor agonist and antagonist,namely acetylcholine(Ach) and atropine(Atr) respectively in an isolated rat heart. results:The physiological parameters like left ventricular developed pressure,end diastolic pressure and working index of isolated rat heart showed significant recovery in DG root extract administrated rat heart,similar to the recovery by *** results showed muscarinic receptor agonist like action for DG methanol root extract,confirmed in rat heart by muscarnic receptor agonist(acetylcholine) and anatoginst(atropine).Administration of DC root extract prior to reperfusion showed better antioxidant status in myocardial tissue homogenate and mitochondrial,complemented by the levels of cardiac specific marker proteins in myocardial tissue and *** though DG methanol root extract mimics its action similar to that of Ach,the myocardial protection mediated by the extract was superior to Ach,due to the presence of antioxidants in the crude ***:DG methanol root extract provides myocardial protection towards IrI by stimulating muscarinic receptors.

关键词： Myocardial ischemia reperfusion Ischemic precondition Ischemic post conditioning Acetyl choline Desmodium gangeticum Muscarinic receptor

Decay of a Mass-Less Field Far from Horizon of a Black Hole

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Communications in Theoretical Physics 2011年第3期55卷 445-448页

作者： jose L. Martinez-Moralest Institute of Mathematics National Autonomous University of Mexico A.P. 273 Admin. De Correos #3 CuernavacaMO 62251 Mexico

Far from the horizon of a black hole of even space dimension n, a mass-less field decays as t1-2t-n in the time, where 1 is a harmonic mode of the sphere.

关键词： black hole horizon even space dimension mass-less field