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Lupinus microcarpus Growing in Arsenic—Agricultural Soils from Chile: Toxic Effects and It Potential Use as Phytoremediator Plant

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Journal of Environmental Protection 2016年第1期7卷 116-128页

作者： Oscar P. Díaz Yasna tapia Rubén Pastene Marcia Cazanga Rodrigo Segura Santiago Peredo Department of Biology Faculty of Chemistry and Biology University of Santiago of Chile Santiago Chile faculty of Agricultural Science University of Chile Santiago Chile Department of Chemistry of Materials Faculty of Chemistry and Biology University of Santiago of Chile Santiago Chile Agrarian Management Department Technology Faculty University of Santiago of Chile Santiago Chile

Arsenic (As) is the most important contaminant of the environment in northern Chile. The purpose of the present work is to study As-toxicity symptoms on Lupino microcarpus (lupine), an annual legume plant that constitutes part of the desert community of the pre-Andean area of the Antofagasta Region, Chile. This plant species is cultivated in As-agricultural soil collected from Chiu Chiu (northern Chile) which is classified as arid soils. Control soil (0 - 20 cm depth) is collected from an area located in the central zone of Chile, which is classified as molli soil. The main physic-chemical characteristics of As-soil and the control soil are determined. Eighteen plastic pots of 1.6 L (fifteen for experimental and three for control) are filled with As-soil and control soil treatments. Two plants are cultivated in each pot and then separated leaves and roots for As-analysis. Visual As-toxicity symptoms such as foliar chlorosis, necrosis of the leaf tips and margins, leaf wilting and stunted are determined. Total As concentrations in soils where lupine is cultivated, reach levels between 5.3 - 14.2 mg·kg-1 d.w. (control soil As-level: 3.1 mg·kg-1). Roots show higher As-concentration than leaves, both experimental plants as control plants (2.28 - 9.1 mg·kg-1 d.w., and 0.76 mg·kg-1 d.w., respectively) and low values of transport index (TI) (0.16 - 0.34). All of visual As-toxicity symptoms determined is showed by lupin cultivated in As-agricultural soils. Neither control lupin plant suffers any toxicity symptoms. The results indicate that lupine plants do not resist contamination and accumulated higher levels of As in roots. Lupine can be used in the phytostabilisation of As immobilizing it by microbial activity in agricultural soil.

关键词： Lupinus microcarpus Arid As-Soil As-Toxicity Phytostabilization

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托管安全业务：从被动监控到主动防御

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网络电信 2007年第1期9卷 18-21页

作者： D．Gras f．Martinez G．Oualid S．tapia

由于故意的安全攻击所引起的网络服务宕机事件越来越频繁，这些事件以往则多半是由于系统故障所引起的。根据Gartner的调查报告，对于那些不采取主动安全防护措施的公司而言，由于软件系统故障所引起的系统宕机事件将在2008年增加至三倍。

关键词：主动防御安全威胁大型企业阿尔卡特安全业务监控 Gartner 能力

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Stressors in Nurse Students’ formation in the New Normality Post COVID-19

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Open Journal of Nursing 2023年第7期13卷 399-410页

作者： Nancy Stephany Viorato-Romero Graciela González-Juárez Alba Luz Robles-Mendoza Diana Cecilia tapia-Pancardo Student Doctoral Program in Nursing National Autonomous University of Mexico México City Mexico faculty of Nursing and Obstetrics National Autonomous University of Mexico Mexico City Mexico Career of Psychology Faculty of Higher Studies Iztacala National Autonomous University of Mexico Mexico City Mexico Graduate and Research Division Biomedicine Unit Faculty of Higher Studies Iztacala National Autonomous University of Mexico Tlalnepantla Mexico

Background: Mental health has been impaired and at risk due to the worldwide COVID-19 pandemic. The consequences due to confinement impacted every scenario, which directly influenced the daily routine of nurse students;in each setting students faced stressors that trigger fear, anxiety and others, since being in confinement learning of topics moved to the home, laboratory practices in hospitals were cancelled leaving the room that is uncertain up to their return to in-person activities. It is important to highlight the need for innovation and strengthening of theoretical-pedagogic aspects centered at the student’s context as a human being with their own needs and problems, who will interact with others in the continuous process of health-illness. Objective: the aim was to identify the stressors in the nurse students’ formation in the new normality post-COVID-19. Methods: Qualitative and phenomenological research with 27 participants aged 20 - 25 years, nurse students of a public university. The information collection was through four focal groups of 6-7 members each, data analysis was done according to Miles & Huberman after signed informed consent of each participant, and authorized by the chairperson of the Nurse’ career. Results: Category 1, Cumulative stressors with sub-categories 1.1 Uncertainty, 1.2 Isolation, 1.3 Invisibility, 1.4 Mockery, 1.5 Exclusion. Category 2, Expectancy states with sub-categories 2.1 Low self-esteem, 2.2 Insecurity, 2.3 Anxiety, 2.4 Depression, 2.5 Temporary leave, 2.6 Search for authenticity. Category 3, Internalization processes with sub-categories 3.1 Social rejection, 3.2 Self-censorship, 3.3 Discrediting, 3.4 Disempowerment. Category 4, Academic aspects affected with sub-categories 4.1 Deficient studying habits, 4.2 Deficient assimilations of knowledge, 4.3 Archived knowledge in the computer, 4.4 Absence of practice in previous semesters. Conclusion: Once identified the stressors in nurse students in the new normality post-COVID-1

关键词： Stressors Nurse Students’ formation New Normality Post COVID-19

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Economic Dispatch Considering Hourly Capacity Allocation with a Variable Renewable and Hydro-Based Generation Portfolio

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Energy and Power Engineering 2022年第10期14卷 594-614页

作者： Roney N. Vitorino Dorel S. Ramos Karen tapia-Ahumada Sergey Paltsev John M. Reilly Energy Research Office Rio de Janeiro Brazil Polytechnic School University of Sao Paulo Sao Paulo Brazil Massachusetts Institute of Technology Cambridge USA

The objective of this paper is to assess an economic dispatch considering a power system portfolio, which includes predominant amount of hydro power and increasing quantities of intermittent renewables in relation to the total electric capacity. With growing importance of intermittent wind and solar generation taking part into power systems worldwide, there is need for greater chronological resolution to estimate the flexibility of the power system to offer firm capacity. In this way, a linear optimization model operating hourly is developed to calculate the minimum power system cost, while stablishing the capacity allocation to meet the projected load throughout one-year simulation, as an estimation of how the hourly economic dispatch impacts the scheduling of generators belonging to a power system with this portfolio composition. A central focus is how to operate the available hydro capacity to back up intermittent renewables, evaluating the physical hydro operating constraints, monthly energy balance and maximum power availability. A case study was simulated based on the Brazil’s power system configuration, showing that existing hydro capacity provide hourly flexibility to back-up intermittent renewables, potentially saving 1.2 Billion R$, about 3.6% of total system cost referred to 2019. It is worthwhile to realize that the developed methodology can be employed to other power systems with similar capacity portfolio structure for the purpose of calculating its optimum allocation for a specified region and target year.

关键词： Economic Dispatch Energy Planning Operation flexibility Power System Transmission System Variable Renewable Energy

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Methodology for Precious Metal Recovery in Computer Printed Circuit

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Journal of Chemistry and Chemical Engineering 2013年第8期7卷 759-766页

作者： Miguel Aguilar Cortest Martha Lilia Dominguez Patifio Antonio Rodriguez Martinez Rene Guardian tapia[ Rosa Maria Melgoza Aleman Engineering and Applied Science Postgraduate School University of A utonomous Morelos State Morelos 62209 Mexico faculty of Chemical Sciences and Engineering University of 4utonomous Morelos State Morelos 62209 Mexico Engineering and Applied Sciences Research Centre University of A utonomous Morelos State Morelos 62209 Mexico

The life of electronic equipment is becoming increasingly shorter and its replacement always generates a quantity of waste increase, giving rise to a problem of environmental character and still needed new options of solid waste management that will contribute to global sustainable development. Parts of these waste are TCI （the card＇s printed circuit） which containing dangerous elements and turns them into a polluting material from the soil, water and air, being harmful to human health if there is to proper and responsible way, so the recycling of TCI to obtain precious metals is an example of industrial materials that can be recycled. Despite this, large quantities of these are not recycled and some others are not considered. The objective of this work is to present a systematic and ecological methodology for the recovery of valuable materials contained in parts of used in computers, circuit boards using a leaching process. The method determines a set of variables to evaluate the kinetics of the reaction and the leaching of metals that form the substrate of metal and to establish the parameters that affect the rate of leaching of metals through a sensitivity analysis, to identify design alternatives. It determines the quantity and percentages that constitutes the motherboard, processor, video cards, accelerator graphics, network and memory cards RAM, among others and its content of metals such as Cu, fe, Ag, Au and Pt.

关键词： Precious metals leaching waste electrical and electronic equipment printed circuit board.

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Detection of dengue virus serotype 3 in Cajamarca,Peru:Molecular diagnosis and clinical characteristics

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Asian Pacific Journal of Tropical Medicine 2021年第10期14卷 456-462页

作者： Miguel Angel Aguilar-Luis Hugo Carrillo-Ng Sungmin Kym Wilmer Silva-Caso Eduardo Verne Luis J.del Valle Jorge Bazán-Mayra Victor Zavaleta-Gavidia Daniel Cornejo-Pacherres Yordi Tarazona-Castro Ronald Aquino-Ortega Angela Cornejo-tapia Juana del Valle-Mendoza School of Medicine Research and Innovation Center of the Faculty of Health SciencesUniversidad Peruana de Ciencias AplicadasLimaPeru Laboratorio de Biologia Molecular Instituto de Investigación NutricionalLimaPeru facultad de Medicina Alberto Hurtado Universidad Peruana Cayetano HerediaLimaPeru Division of Infectious Diseases Department of Internal MedicineChungnam National University School of MedicineDaejeonRepublic of Korea Barcelona Research Center for Multiscale Science and Engineering Departament d'Enginyeria QuímicaEEBEUniversitat Politècnica de Catalunya(UPC)BarcelonaSpain Laboratorio Regional de Cajamarca Dirección Regional de Salud de Cajamarca(DIRESA)CajamarcaPeru

Objective:To describe and molecularly characterize an outbreak of dengue virus(DENV)infection in Cajamarca,an Andean region in ***:A total of 359 serum samples from patients with acute febrile illness were assessed for the presence of DENV via RT-PCR,ELISA NS1,Ig M and Ig G in Cajamarca,Peru from January 2017 to June *** evaluation of the different diagnostic tests and their applicability was ***:Dengue virus was detected in 24.7%of samples by ***,serological analysis detected 30.3%positive cases via ELISA NS1 antigen,16.7%via ELISA Ig G and 9.7%via ELISA Ig *** of the cases corresponded to DENV-3(77.5%).The use of RT-PCR performed better in primary infections(Pf ELISA Ig M performed better in secondary infections(Pf NS1 and Ig M performed better than the other assays in detecting primary(92.5%)and secondary infections(96.6%).The most frequent symptoms associated with fever were headaches,myalgias,and arthralgias across all ***:We report an important outbreak of dengue infection caused by DENV-3 in Cajamarca,*** findings encourage the use of NS1 antigen and Ig M *** findings demonstrate an increasing expansion of DENV-3 in Peru and highlight the importance of molecular diagnosis and serotype characterization among the clinically defined dengue cases to strengthen the Peruvian epidemiological surveillance.

关键词： Dengue DENV Arbovirus Diagnosis Peru

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Lipid Profile and Antioxidant Activity of Macadamia Nuts (<i>Macadamia integrifolia</i>) Cultivated in Venezuela

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Natural Science 2015年第12期7卷 535-547页

作者： Alejandra Rengel Elevina Pérez George Piombo Julien Ricci Adrien Servent María Soledad tapia Olivier Gibert Didier Montet Instituto de Ciencia y Tecnología de Alimentos Facultad de Ciencias Universidad Central de Venezuela Caracas Venezuela Cirad UMR Iate Campus de la Gaillarde 2 place Pierre Viala Montpellier France Cirad UMR 95 Qualisud TA B-95/16 73 rue Jean-Francois Breton Montpellier France

Macadamia nuts (Macadamia integrifolia) grown in Venezuela have showed an average total fat content of 70%. Oleic acid (18:1) was the main monounsaturated fatty acid (MUfA) (51.3%), followed by palmitoleic acid (16:1, 22.6%). The content of polyunsaturated fatty acids (PUfAs), C18:2 and C18:3 represented 5.4%. Thus, MUfAs and PUfAs together constituted more than 80% of the total fatty acids present. Trans-vaccenic acid was also present (3%). As regards to other phytochemical compounds, tocopherols and tocotrienols were not found in the sample, but the presence of squalene was *** antioxidant activity (44.2%) of the extract was produced by the phytochemicals present.

关键词： Lipids Antioxidant Activity fatty Acids Macadamia Nut Phytochemical Compounds

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Low serum levels of ghrelin are associated with gallstone disease

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World Journal of Gastroenterology 2006年第19期12卷 3096-3100页

作者： Nahum Méndez-Sánchez Guadalupe Ponciano-Rodríguez Luisa Bermejo-Martínez Antonio R Villa Norberto C Chávez-tapia Daniel Zamora-Valdés Raúl Pichardo-Bahena Blanca Barredo-Prieto Martha H Uribe-Ramos Martha H Ramos Héctor A Baptista-González Misael Uribe Liver Unit Biomedical Research Department Medica Sur Clinic and FoundationMexico CityMexico faculty of Medicine National Autonomous University of Mexico (UNAM) Mexico CityMexico Clinical Research Department National Institute of Perinatology Mexico CityMexico Clinical Epidemiology Unit National Institute of Medical Sciences and Nutrition Mexico CityMexico

AIM： To explore the role of ghrelin in gallstone disease. METHODS： We carried out a cross-sectional study in 150 subjects, 38 with gallstones （cases） and 112 controls. We also did a real-time PCR-RT study in twenty gallbladder samples each. Body mass index （BNI）, serum insulin, ghrelin, and serum lipids were measured. Logistic regression analyses （univariate and multivariate） were conducted to estimate the probability of gallstone disease associated with serum ghrelin concentrations. RESULTS： Cases were statistically different from controls in gender distribution （P = 0.01）, age （53 vs 44 yr, P = 0.002）, BNI （28 vs 25; P = 0.004）, and glucose （5.26 vs 4.98 mmol/L; P = 0.05）. The prevalence of ghrelin serum levels above the third tercile was lower in subjects without metabolic syndrome （P 〈 0.05）. In a multivariate model, we found a protective effect, when ghrelin values were higher than the median value （OR = 0.27, 95%CI 0.09-0.82, P = 0.02）. Twenty （20%） gallbladder specimens expressed ghrelin mRNA. CONCLUSION： Serum ghrelin concentrations are associated with a protective effect of GD.

关键词： Gallstones Obesity Ghrelin Gallbladder Gastrointestinal hormones

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On Redefining the Onset of Baseflow Recession on Storm Hydrographs

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Open Journal of Modern Hydrology 2013年第4期3卷 269-277页

作者： R. Pizarro-tapia f. Balocchi-Contreras P. Garcia-Chevesich K. Macaya-Perez Per Bro L. León-Gutiérrez B. Helwig R. Valdés-Pineda Department of Hydrology and Water Resources University of Arizona Tucson Arizona Dirección General de Aguas Santiago Chile. University of Talca Centro Tecnológico de Hidrología Ambiental Talca Chile University of Talca Centro Tecnológico de Hidrología Ambiental Talca Chile

Two methods that define the point of baseflow recession onset were compared using storm hydrograph data for 27 storm events that occurred between 1982-1995 in the Upeo watershed located in the Andes mountain range in central Chile (figure 1). Three well-known baseflow recession equations were used to determine whether the method we are proposing here, that defines baseflow recession onset as the third inflection point on the logarithmic graph of the falling limb of the storm hydrograph, more accurately models observed data than the most widely used method that defines baseflow onset as the second inflection point on the same graph. five time intervals were used to modify the recession coefficient in search of a more accurate fit. Results from the coefficient of determination, standard error, Mann-Whitney U test, and Bland-Altman test suggest that redefining baseflow recession onset via the proposed approach more accurately models baseflow recession behavior.

关键词： Baseflow Recession Hydrograph Separation Hydrologic Modeling Recession Analysis Baseflow Onset

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Study of the Copper,Chromium,Manganese and Zinc Contents in the Species Azorella spinosa(Apiaceae),Collected in the Maule Region,Chile

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Journal of Environmental Protection 2019年第5期10卷 601-613页

作者： Jaime tapia Jorge Cornejo Margarita Gutierrez Patricio Penailillo Ricardo Baettig Luis Vargas-Chacoff Jessica Espinoza Aurelio San Martin Institute of Natural Resources Chemistry University of TalcaTalcaChile Institute of Biological Sciences University of TalcaTalcaChile faculty of forestry Sciences University of TalcaTalcaChile Institute of Marine Science and Limnology University Austral of ChileValdiviaChile University of Magallanes Punta ArenasChile

The increase in prevalence of environmental pollution, especially soil contamination with toxic metals has led to their uptake in the human food chains through plant parts. Accumulation and magnification of heavy metals in human tissues through comsuption of herbal medicine can cause hazardous impacts on health. Therefore, chemical profiling of four heavy metals (Cu, Cr, Mn and Zn) was undertaken in samples of Azorella spinosa from coast and mountain of Maule Region in Chile. The Cu, Cr, Mn and Zn concentrations were determined in plants of the species Azorella spinosa and their soils of origin. for each plant, the metal contents in the stalk, leaves and soil were determined by flame atomic absorption spectroscopy. The methodology was validated using certified reference material: BIMEP-432 for the plant samples and MESS-1 for the soil samples. The concentration ranges found in the plant tissue were: Cu: 1.2 - 62.5;Cr: 0.2 - 3.2;Mn: 188.6 - 1345.1 and Zn: 7.5 - 55.9 mg·kg-1 (dry weight). for the soil samples, the ranges were: Cu: 6.4 - 81.5;Cr: 4.6 - 50.4;Mn: 335.6 - 1936.1 and Zn: 15.6 - 65.9 mg·kg-1 (dry weight). The results were evaluated statistically (two-way ANOVA) to correlate the Cu, Cr, Mn and Zn concentrations in Azorella spinosa plant tissues with those in the soil samples from the corresponding sampling areas.

关键词： Azorella spinosa Toxic Metals Atomic Absorption Maule Region

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