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Journal of Environmental Sciences 2012年第5期24卷 912-918页

作者： Tatiana Garrido Jorge Mendoza francisco Arriagada Faculty of Chemical Sciences and Pharmacy Department of Inorganic and Analytical Chemistry University of Chile

The effect of mine tailings and sewage sludge was evaluated on sorption, desorption, availability and distribution of copper in two soils, one high （sandy soil） and one low in copper （clay soil）. In both soils contaminated by mine tailings the copper sorption capacity and the affinity of the substrate for the metal decreased substantially compared to the uncontaminated soils, however, the sorption remained always high in the clay soil substrates. In the substrates with sandy soil, the high Cu content and lower clay content were determining factors in the lower magnitude of the sorption. Similarly, metal desorption was closely related to these two parameters, and it was higher in clay soil with lower pH. In general, the application of sewage sludge favored the sorption of Cu in soils contaminated and uncontaminated with mine tailings, and in all cases desorption decreased, an effect that remained for at least 30 days. Simple extraction of Cu with CaCl2 and diethylenetriaminepentaacetic acid gave contradictory results, so a careful choice of the procedure is required, depending on the level of metal in the soil and on the acting principle of the extracting agent. In that relation, more complete information on the changes in the metal forms was obtained by application of the sequential extraction procedure proposed by the European Community Bureau of Reference.

关键词： sewage sludge copper sorption mine tailings copper desorption European Community Bureau of Reference sequential extraction

Ecophysiology of egg rejection in hosts of avian brood parasites:new insights and perspectives

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Current Zoology 2021年第6期67卷 631-638页

作者： francisco RUIZ-RAYA Centro de Investigación Marina Universidade de VigoGEAVigo 36310Spain

Egg rejection is the most effective and widespread defense used by host species to counteract the extreme fitness costs frequently imposed by obligate avian brood ***,the proximate mechanisms underlying between-and within-individual variation in host responses remain poorly *** evidence suggests that egg rejection is dependent on individual physiological states,and draws attention to the role of hormones as mediators of flexible antiparasitic *** this perspective article,I outline recent advances in our understanding of the proximate factors that mediate egg rejection.I also point out some areas where knowledge remains still lacking,especially those related to the development and maintenance of effective cognitive functions,the potential role of oxidative stress,immunological state,and developmental stressors.I propose new hypotheses that stimulate future research on behavioral host responses toward brood parasitism.

关键词： cognitive performance condition-dependence corticosterone flexible responses prolactin

Work Ability Index and Work Ability Score: A Comparation between both Scores in a Persistent COVID-19 Cohort

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Occupational Diseases and Environmental Medicine 2024年第1期12卷 49-57页

作者： Carmen muñoz-Ruiperez Diego Alvaredo Rodrigo Daniel Arroyo-Sánchez Juan francisco Álvarez Zarallo Ignacio Sánchez-Arcilla Conejo José Lorenzo Bravo Grande Department of Occupational Health Hospital Universitario 12 de Octubre Madrid Spain Instituto de Investigación Biomédica Hospital 12 de Octubre (Imas12) Madrid Spain Department of Occupational Health Hospital Universitario Virgen Macarena Andalucía Sevilla Spain Department of Occupational Health Hospital Universitario Gregorio Mara&#241ón Madrid Spain Department of Occupational Health Complejo Asistencial Universitario de Salamanca Castilla y León Salamanca Spain

Aims: The present study aims to compare the assessment of work ability based on the use of the Work Ability Index (WAI) with another questionnaire base only on the use of WAI’s first item, termed as the “Work Ability Score” (WAS). Study design: A cohort of 384 Spanish workers included in a Post COVID-19 condition or persistent COVID-19 multicenter research was utilized. Place and Duration of Study: This cohort was enlisted in four hospitals (Hospital Universitario 12 de Octubre, Madrid;Hospital Universitario Virgen Macarena, Sevilla, Andalucía;Hospital Universitario Gregorio Marañón, Madrid and Complejo Asistencial Universitario de Salamanca, Castilla y León), since 2021 until 2022. Methodology: 384 Spanish workers (176 men and 208 women;aged 20 to 70 years) with Post COVID-19 condition or persistent COVID-19 were included. Descriptive analysis of primary scores was conducted. Given the non-normal distribution of data, the Mann-Whitney and Kruskal-Wallis tests were employed. Spearman and Kendall correlations were employed to assess the relationship between WAI and WAS, also used weighted Kappa to estimate the degree agreement between WAI and WAS. Logistic regression models were utilized to study determinants influencing WAI and WAS, categorized as poor or moderate. Results: WAI had an average score of 32.98 (SD = 10.28), whereas WAS had an average of 5.95 (SD = 2.77). Significant differences were observed in both WAI and WAS across the same variables. Strong and statistically significant correlations were evident between WAI and WAS (rs = 0.83, p < 0.001). All the variables used in the logistic regression model (gender, the sector employment, and previous chronic diseases) were statistically significant in both questionnaires. Conclusion: WAS questionnaire could be used as a tool for reliable assessment of work ability among Spanish workers with Post COVID-19 condition or Persistent CO-VID-19.

关键词： Work Ability Index Work Ability Score Post COVID-19 Condition Occupational Health Occupational Medicine

Different patterns of intestinal response to injury after arterial,venous or arteriovenous occlusion in rats

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World Journal of Gastroenterology 2009年第31期15卷 3901-3907页

作者： francisco Javier Guzmán-de la Garza Carlos Rodrigo Cámara-Lemarroy Gabriela Alarcón-Galván Paula Cordero-Pérez Linda Elsa muoz-Espinosa Nancy Esthela Fernández-Garza Department of Physiology Autonomous University of Nuevo LeónSchool of Medicine Pathologic Anatomy and Cytopathology Service "José Eleuterio González" University Hospital Liver Unit Department of Internal MedicineAutonomous University of Nuevo LeónSchool of Medicine

AIM： To investigate the differences in injury patterns caused by arterial, venous or arteriovenous mesenteric occlusion. METHODS： Male Wistar rats were separated equally into four groups. Occlusion was performed by clamping the superior mesenteric artery （A）, the mesenteric vein （V） or both （AV） for 30 min, followed by 60 min of reperfusion. A control group received sham surgery only. Intestinal sections were examined for histological damage and serum tumor necrosis factor-α （TNF-α）, endothelin-1 （ET-1）, P-selectin, antithrombin Ⅲ （AT Ⅲ） and soluble intracellular adhesion molecule-1 （ICAM-1） concentrations were measured. RESULTS： All groups showed significant mucosal injury compared to controls. Furthermore, mucosal injury was significantly more severe in the V and AV groups compared to the A group （3.6 ± 0.55, 3.4 ± 0.55 and 2± 0.71, respectively, P = 0.01）. ICAM-1 was similarly elevated in all groups, with no significant differences between the groups. P-selectin levels were significantly elevated in the V and AV groups but not the A group （1.4 ± 0.5 ng/mL, 2.52 ± 0.9 ng/mL and 0.02± 0.01 ng/mL, respectively, P = 0.01） and ET-1 was significantly elevated in the A and V groups but not the AV group （0.32 ± 0.04 pg/mL, 0.36 ± 0.05 pg/mL and 0.29 ± 0.03 pg/mL, respectively, P = 0.01） compared to sham controls. ATⅢ levels were markedly depleted in the V and AV groups, but not in the A group （29.1 ± 5.2 pg/mL, 31.4 ±21.8 pg/mL and 55.8± 35.6 pg/mL, respectively, P = 0.01）, compared to controls. Serum TNF-α was significantly increased in all groups compared to sham controls （1.32 ± 0.87 ng/mL, 1.79 ± 0.20 ng/mL and 4.4 ± 0.69 ng/mL, for groups A, V and AV, respectively, P = 0.01）, with higher values in the AV group. CONCLUSION： Different patterns of response to ischemia/reperfusion are associated with venous, arterial or arteriovenous occlusion. Venous and arteriovenous occlusion was associated with the most severe alterations

关键词： Arterial occlusion Rat Intestine Ischemia/ reperfusion Venous occlusion

Symplectic feedback using Hamiltonian Lie algebra and its applications to an inverted pendulum

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控制理论与应用（英文版） 2013年第2期11卷 275-281页

作者： J. Lorca ESPIRO C. munoz POBLETE Departamento de Ciencias Fisicas Facultad de Ingenieria Ciencias y Administracion Universidad de La FronteraAvenida Francisco Salazar 01145 Casilla 54-D Temuco Chile Departamento de Ingenieria Electrica Facultad de Ingenieria Ciencias y Administracion Universidad de La FronteraAvenida Francisco Salazar 01145 Casilla 54-D Temuco Chile

From the symplectic representation of an autonomous nonlinear dynamical system with holonomic con- straints, i.e., those that can be represented through a symplectic form derived from a Hamiltonian, we present a new proof on the realization of the symplectic feedback action, which has several theoretical advantages in demonstrating the uniqueness and existence of this type of solution. Also, we propose a technique based on the interpretation, construction and character- ization of the pull-back differential on the symplectic manifold as a member of a one-parameter Lie group. This allows one to synthesize the control law that governs a certain system to achieve a desired behavior; and the method developed from this is applied to a classical system such as the inverted pendulum.

关键词： Hamiltonian systems Symplectic structures Lie algebra Nonlinear dynamical systems Geometric con-trol

Hydrolysis of Urea to Produce Ammonia Dircio francisco Xavier Fatima Ximenes

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Hydrolysis of Urea to Produce Ammonia Dircio Francisco Xavie...

作者： Dircio francisco Xavier Fatima Ximenes（弗朗西斯科）华东理工大学

学位级别：硕士

氮氧化物（NOx）引起了巨大的环境问题,是目前世界上最大的环境污染物之一,随着对NOx法规的逐步收紧,世界各国都在积极开展减少NOx污染的研究。目前已开发利用了多种技术,其中选择性催化还原（SCR）和选择性非催化还原（SNCR）具有较高... 详细信息

氮氧化物（NOx）引起了巨大的环境问题,是目前世界上最大的环境污染物之一,随着对NOx法规的逐步收紧,世界各国都在积极开展减少NOx污染的研究。目前已开发利用了多种技术,其中选择性催化还原（SCR）和选择性非催化还原（SNCR）具有较高的脱硝效率。在SCR和SNCR工艺中,还原剂被注入烟气中,将NOx还原为无害氮（N2）。目前最常用的还原剂是氨（NH3）。尿素催化水解制氨在氨基脱氮过程中起着重要作用。本论文的目标有三个。首先,对尿素水解的催化剂进行筛选,其中均相催化剂表现出了良好的性能,因此本文用选择该类催化剂来进行尿素催化水解反应,然后尿素水解的转化率采用滴定法来进行分析。第二是设计了四因素,三水平Box-Behnken实验,结合响应面法对工艺条件进行优化,研究反应温度,反应时间,反应压力和催化剂用量对尿素水解制氨的影响及其交互作用。建立了尿素水解率的相关模型。第三是采用物料平衡方程,热量平衡方程,化学平衡方程及相平衡方程组成的非线性方程组来构建开口体系内尿素水解过程的热力学模型和动力学模型,并引入修正的Lewis-Randall方程和修正的Herry方程来描述水解反应器内NH3-CO2-H2O-（NH2）2CO（ACWU）四元多自由度气液平衡关系,气液两相的非理想性则分解采用PR状态方程和扩展UNIQUAC模型进行修正。结果表明,采用催化活性较好的乙酸钠（7g）催化剂对工艺条件进行优化,响应面法最优化的合成条件为;反应温度160℃,反应时间4h,反应压力0.4MPa和催化剂用量0.034wt%,在此工艺条件下尿素水解的转化率为98.620%,同时建立了尿素水解制氨的二次数学模型,该模型对实验结果有良好的预测作用。

关键词：尿素水解制氨热力学动力学

Impact of ZnSO_(4)^(-)and ZnO Nanoparticles on Seed Germination and Seedling Growth of Lettuce

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Phyton-International Journal of Experimental Botany 2023年第6期92卷 1831-1840页

作者： Adalberto Benavides-Mendoza Rebeca Betancourt-Galindo Nazario francisco-francisco Departamento de Horticultura Universidad Autónoma Agraria Antonio NarroSaltillo25315México Departamento de Materiales Avanzados Centro de Investigación en Química AplicadaSaltillo25294México Departamento de Agricultura Sustentable y Protegida Universidad Tecnológica de TehuacánTehuacán75859México

Micronutrient nanoparticles(NPs)are currently an option for chemical fertilization and biostimulation in ***,there is little information on the phytotoxic or biostimulatory effects of NPs at low concentrations of some elements,such as *** this study,the effect of low concentrations of Zn oxide(ZnO)NPs on germination,growth variables,and nutritional attributes of lettuce(Lactuca sativa L.)was evaluated in comparison to Zn *** lettuce seeds were treated with ZnSO_(4)^(-)×7H_(2)O and ZnO NPs at Zn molar concentrations of 1×10^(−3),5×10^(−3),1×10^(−4),5×10^(−4),1×10^(−5),5×10^(−5),1×10^(−6),and 5×10^(−6).The seeds treated with ZnSO4−at 5×10^(−6)registered the highest radicle length,73%more than the control *** seeds treated with ZnSO4−at 5×10^(−3)registered the lowest values,with 50%less than the control *** NPs at 5×10^(−6)significantly increased content of chlorophyll A and B and total *** results indicate the possible existence of a mechanism related to the intrinsic nanoparticle properties,especially at low concentrations.

关键词： Micronutrients biostimulation nanotechnology nanofertilizers germination chlorophyll total phenols

The quest for selective Cs^(+) transport in plants

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Molecular Plant 2021年第4期14卷 552-554页

作者： Manuel Nieves-Cordones francisco Rubio Departamento de Nutricion Vegetal Centro de Edafologia y Biologia Aplicada del Segura-CSICCampus de Espinardo30100 MurciaSpain

Nuclear accidents have led to the release to the environment of radioactive isotopes,mainly radioactive cesium(Cs^(+)),contaminating large areas of soil for very long periods of time(Burger and Lichtscheidl,2018).These contaminated soils contain^(134)Cs^(+)and^(137)Cs^(+)radioisotopes that are readily accumulated into plants and that,through the food chain,are transferred to animals and humans,causing important health problems(Burger and Lichtscheidl,2018).

关键词： readily release transport

SPLITTING SCHEMES FOR A NAVIER-STOKES-CAHN-HILLIARD MODEL FOR TWO FLUIDS WITH DIFFERENT DENSITIES

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Journal of Computational Mathematics 2014年第6期32卷 643-664页

作者： francisco Guillen-Gonzalez Giordano Tierra Departamento de Ecuaciones Diferenciales y Andlisis Numgrico and ImuS Universidad de Sevilla 41012 Seville Spain Department of Applied and Computational Mathematics and Statistics University of Notre Dame Notre Dame IN 46556 USA

In this work, we focus on designing efficient numerical schemes to approximate a ther- modynamically consistent Navier-Stokes/Cahn-Hilliard problem given in [3] modeling the mixture of two incompressible fluids with different densities. The model is based on a diffuse-interface phase-field approach that is able to describe topological transitions like droplet coalescense or droplet break-up in a natural way. We present a splitting scheme, decoupling computations of the Navier-Stokes part from the Cahn-Hilliard one, which is unconditionally energy-stable up to the choice of the potential approximation. Some nu- merical experiments are carried out to validate the correctness and the accuracy of the scheme, and to study the sensitivity of the scheme with respect to different physical pa- rameters.

关键词： Two-phase flow Diffuse-interface phase-field Cahn-Hilliard Navier-Stokes,Energy stability Variable density Mixed finite element Splitting scheme.

Increasing Powers in a Degenerate Parabolic Logistic Equation

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Chinese Annals of Mathematics,Series B 2013年第2期34卷 277-294页

作者： Jos francisco RODRIGUES Hugo TAVARES Department of Mathematics and CMAF Universidade de LisboaAvenida Professor Gama Pinto 21649-003 LisboaPortugal

The purpose of this paper is to study the asymptotic behavior of the positive solutions of the problem tu- △u=au-b（x）up in Ω×R＋,u（0）=u0,u（t ）｜ Ω=0, as p→ ＋∞, where Ω is a bounded domain, and b（x） is a nonnegative function. The authors deduce that the limiting configuration solves a parabolic obstacle problem, and afterwards fully describe its long time behavior.

关键词： Parabolic logistic equation Obstacle problem Positive solution Increasing power Subsolution and supersolution