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Frontier of the Paleo-Tethys Ocean in the western mediterranean:Isotopic(Sm-Nd)constraints on sources of Devonian units from menorca Island

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Geoscience Frontiers 2024年第5期15卷 323-338页

作者： Ricardo Arenas Jose m.Fuenlabrada Cristian Timoner Rubén Díez Fernández Esther Rojo-Pérez Departamento de mineralogía y Petrología and Instituto de Geociencias(UCm CSIC)Universidad ComplutenseMadridSpain Unidad de Geocronología(CAI de Ciencias de la Tierra y Arqueometría) Universidad ComplutenseMadridSpain Bayerisches Geoinstitut University of BayreuthBayreuthGermany Instituto Geológico y minero de España–CSIC SalamancaSpain

The c.1000-m-thick pre-orogenic Devonian mainly metapelitic sequence of North menorca Island shows a fairly complete stratigraphic *** rocks of this sequence indicate gradually increasing deeper marine conditions of sedimentation towards its uppermost ***,the obtained sedimentary characteristics resemble those related to a deep and narrow basin-associated *** sills of Ti-augite-bearing alkaline gabbros occur within the Devonian *** intensity of Variscan deformation increases downwards through the *** to the characteristics of the Devonian sequence and its location within the Variscan Orogen,a correlation with similar units located in the southern sectors of the Central Iberian Zone(Iberian massif)is *** Devonian metapelitic rocks have geochemical characteristics suggesting that they represent moderately recycled mature siliciclastic sediments,generated from erosion of distant source areas belonging to an upper continental *** relatively narrow range of variation observed in initial^(143)Nd/^(144)Nd ratios supports a similar source for the menorcan slates(0.51165–0.51182).However,a marked trend is observed in these isotope ratios,from lower values at the base of the stratigraphic column(minimum value of 0.511941)to higher values at the top(maximum value of 0.512131).The^(147)Sm/^(144)Nd ratios vary between 0.1074 and 0.1238,within the range defined for siliciclastic rocks with felsic crustal *** Nd model ages define a narrow range between 1496 ma and 1754 ma(Late Paleoproterozoic–Early mesoproterozoic),and they are consistently younger *** data rule out a provenance from the erosion of the West Africa Craton,as they are more compatible with a provenance from regions located in the Trans-Saharan Belt or Sahara *** characteristics of the menorcan Devonian sequence are compatible with its deposition in a narrow and deep peri-Gondwanan transtensional basin,gener

关键词： Western Paleo-Tethys frontiers menorca Island Sm-Nd isotopic constraints Devonian sequence provenance in Gondwana

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Supply mix Optimization for Decentralized Energy Systems

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Open Journal of Applied Sciences 2013年第2期3卷 5-11页

作者： J. K. Gruber J. L. mínguez Fernández m. Prodanovic Electrical Systems Unit IMDEA Energy Institute Móstoles (Madrid) Spain

In recent years, the energy sector has undergone an important transformation as a result of technological progress and socio-economic development. The continuous integration of renewable energy sources forces a gradual transition from the traditional business model based on a reduced number of large power plants to a more decentralized energy production. The decentralization and the increased number of energy sources lead to a series of new challenges in the energy sector. This paper presents an approach to determine the optimal energy supply mix for small and medium sized buildings or installations. The optimization algorithm considers the electricity and heat demand and determines the optimal combination of energy sources by minimizing an economic index. The optimization problem can be solved for multiple demand profiles and takes into account the possibility to integrate accumulator systems. The proposed approach provides a high degree of flexibility and can be used to study the influence of the energy prices on the optimal energy supply mix. The performance of the proposed optimization approach is illustrated by the results obtained from a simulation example.

关键词： Energy Supply mix Optimal Configuration Decentralized Generation

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Environmental and Economic Impact of Forest Fires in Puerto Rico 2013-2014

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Open Journal of Forestry 2015年第4期5卷 353-363页

作者： méndez-Tejeda Rafael Santos-Corrada maría Ortiz-morales Sergio Claudio-Vargas Oscar Natural Science Department Atmospherical Science Laboratory University of Puerto Rico—Carolina Campus Carolina Puerto Rico School of Business and Entrepreneurship University of Turabo Gurabo Puerto Rico

This study presents an analysis of the impact of forest fires in Puerto Rico for the period from 2013-2014. The climatological factors analyzed included precipitation, temperature, relative humidity, and wind. Several factors have combined to the increase of these forest fires, among others, a decrease in precipitation during this period, as well as an increase in the human involvement in these fires from approximately 40% occurs in the night period (5:00 pm to 8:00 am), where the weather conditions do not favor the appearance of these phenomena. An increase in fires of 44% occurred in 2013 compared to 2014, causing an economic loss of $13.8 million. Fire also adversely affected the flora and fauna of the island, but this was not evaluated in this paper.

关键词： Fires Forest Wildfire Economic Impact of Forest fires Precipitation and Weather Conditions

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Outcomes of the Clean Development mechanism in Argentina

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American Journal of Climate Change 2016年第4期5卷 431-447页

作者： Gabriel Blanco Verónica Córdoba Romina Baldi mónica Fernández Estela Santalla Centro de Tecnologías Ambientales y Energía Facultad de Ingeniería UNCPBA Olavarría Argentina

This paper summarizes the results of the implementation of the CDm in Argentina during the first period of commitment of the Kyoto Protocol. From a total of sixty- five projects ideas, forty-four achieved registration under the CDm EB while the rest remained approved at national level (12), under evaluation (2), suspended (5) or rejected (2). most of the projects focused on the generation of electricity from renewable energy, mainly wind energy and the use of landfill gas and methane for energy. Emissions reductions achieved 33.4% of the expected CERs up to 2012 with strong differences among sectors. Results demonstrated that under the current Argentina’s energy policy framework, the income by the selling of CERs covered less than 6% of the incremental costs for renewable energy projects. A sensitivity analysis to evaluate the impact of CDm in the coverage of incremental costs for renewable energy based on the prices of both the energy in the local market and the CER demonstrated that the best conditions would only cover 15% of those costs. The contribution of CDm to technology transfer in Argentina was minor considering that 45% of the projects qualified as type III where technological learning and capacity building were limited at the level of operation and maintenance of a foreign technology. Domestic and external barriers that prevented a better performance of CDm projects in terms of GHG mitigation, technology transfer and the contribution to a sustainable development were also analyzed.

关键词： Clean Development mechanism GHG Emissions Incremental Cost Renewable Energy Argentina

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Learning to bag with a simulation‐free reinforcement learning framework for robots

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IET Cyber-Systems and Robotics 2024年第2期6卷 52-66页

作者： Francisco munguia-Galeano Jihong Zhu Juan David Hernández Ze Ji Cooper Group University of LiverpoolLiverpoolUK School of Physics Engineering and Technology University of YorkYorkUK School of Computer Science and Informatics Cardiff UniversityCardiffUK School of Engineering Cardiff UniversityCardiffUK

Bagging is an essential skill that humans perform in their daily ***,deformable objects,such as bags,are complex for robots to manipulate.A learning-based framework that enables robots to learn bagging is *** novelty of this framework is its ability to learn and perform bagging without relying on *** learning process is accomplished through a reinforcement learning(RL)algorithm introduced and designed to find the best grasping points of the bag based on a set of compact state *** framework utilises a set of primitive actions and represents the task in five *** our experiments,the framework reached 60% and 80% success rates after around 3 h of training in the real world when starting the bagging task from folded and unfolded states,***,the authors test the trained RL model with eight more bags of different sizes to evaluate its generalisability.

关键词： reinforcement learning robot learning robotics

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BSN:The First Light Curve Analysis of the Total Eclipse Binary System EL Tuc

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Research in Astronomy and Astrophysics 2024年第10期24卷 66-75页

作者： Elham Sarvari Eduardo Fernández Lajús Atila Poro Independent researcher TehranIran Instituto de Astrofísica de La Plata(CCT La Plata-CONICET-UNLP) La PlataArgentina BSN Project &Astronomy Department of the Raderon AI Lab.BurnabyBCCanada

We conducted the first light curve study of the binary star EL Tuc within the Binary Systems of South and North project's *** photometric observations were made using standard multiband BVR_cI_c filters at an observatory in *** presented a new ephemeris for EL Tuc and a linear fit to the O–C diagram,utilizing our extracted times of minima and additional *** employed the PHysics Of Eclipsing BinariEs Python code and the markov chain monte Carlo approach for the system's light curve *** target system's light curve solution required a cold starspot on the hotter *** conclude that EL Tuc is a total contact binary system with a low mass ratio of q=0.172±0.002,an orbital inclination of i=83°.74±0°.40,and a fillout factor of f=53.7%±1.6%.We used the P-a relationship and the Gaia Data Release 3 parallax method to determine the absolute parameters of EL Tuc to compare the precision of our *** system was classified as W-type based on the mass and effective temperature of the companion *** positions of the systems were depicted on the m-L,m-R,T-m,and *** relationship between the spectroscopic and photometric mass ratios of binaries was discussed.

关键词： (stars:)binaries:eclipsing stars:individual(EL Tuc) line:identification

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AN OPTImAL CONTROL PROBLEm FOR A LOTKA-VOLTERRA COmPETITION mODEL WITH CHEmO-REPULSION

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Acta mathematica Scientia 2024年第2期44卷 721-751页

作者： Diana I.HERNÁndez Diego A.RUEDA-GOmEZ Élder J.VILLAmIZAR-ROA Universidad Industrial de Santander Escuela de MatemáticasA.A.678BucaramangaColombia

In this paper we study a bilinear optimal control problem for a diffusive Lotka-Volterra competition model with chemo-repulsion in a bounded domain of ℝ^(ℕ),N=2,*** model describes the competition of two species in which one of them avoid encounters with rivals through a chemo-repulsion *** prove the existence and uniqueness of weak-strong solutions,and then we analyze the existence of a global optimal solution for a related bilinear optimal control problem,where the control is acting on the chemical ***,we derive first-order optimality conditions for local optimal solutions using the Lagrange multipliers ***,we propose a discrete approximation scheme of the optimality system based on the gradient method,which is validated with some computational experiments.

关键词： Lotka-Volterra chemo-repulsion optimal control optimality conditions

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Antibacterial Activity of <i>Bougainvillea Glabra, Eucalyptus Globulus, Gnaphalium Attenuatum</i>, and Propolis Collected in mexico

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Pharmacology & Pharmacy 2012年第4期3卷 433-438页

作者： Oswaldo Javier Enciso-Díaz Alfonso méndez-Gutiérrez Lourdes Hernández De Jesús Ashutosh Sharma maría Luisa Villarreal Alexandre Cardoso Taketa Centro de Investigación en Biotecnología Universidad Autónoma del Estado de Morelos Cuernavaca Morelos Mexico CIDHEm - Centro de Investigación y Docencia en Humanidades del Estado de morelos Morelos Mexico Departamento de Farmacia Escuela Nacional de Ciencias Biológicas Instituto Politécnico Nacional Ciudad de México Mexico

Bougainvillea glabra C., Eucalyptus globules Labill., and Gnaphalium attenuatum DC., as well as propolis, have been used in mexican traditional medicine as a remedy to treat respiratory illnesses. There are few biological reports of such material collected in mexico, despite the high demand for them as raw material for popular and industrial uses. The antibacterial activity of the plants and propolis studied here were evaluated against a panel of bacteria using three different methodologies: agar disc diffusion, macro and micro dilution methods. E. globules and G. attenuatum extracts showed the strongest active values (P > 0.05) in the agar disc diffusion method with a range of 8 - 22 mm inhibition zone, mIC values ranging from 25 - 250g/mL, and mBC values of 25 - 500g/mL obtained by macro and micro dilution methods. B. glabra extracts were active against E. coli, S. typhi, K. pneumoniae, S. aureus and S. agalactiae, with 8 - 13 mm inhibition zone, mICs ranging from 500 - 3000g/mL, and mBCs of 1000 - 3000g/mL. The propolis extract turned out to be active against E. coli, K. pneumoniae, S. aureus and S. agalactiae, with values of 7 - 12 mm, mICs of 1000 - 2000g/mL, and mBCs of 2000 - 2500g/mL. E. globules and G. attenuatum extracts were the most active in the three methodologies assayed. This is also the first time that the antibacterial activity of G. attenuatum has been experimentally demonstrated. The microdilution method showed to be more sensitive, less expensive and minor time-consuming technique compared with the other two.

关键词： Antibacterial Activity Bougainvillea Glabra Eucalyptus Globulus Gnaphalium Attenuatum mexican Ethnomedicine Propolis

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Endoscopic Sphinterotomy in Patients with mild Acute Biliary Pancreatitis, in <i>Situ</i>Gallbladder and Alithiasic Bile Duct: Is It Justified?

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Open Journal of Gastroenterology 2021年第7期11卷 118-133页

作者： mario Anselmi méndez Ana maría Gemmato Pascazi Julio Salgado Oyarzún maritza Flores Opazo General and Digestive Surgery Department School of Medicine University of Concepción Concepcion Chile Public Health Department School of Medicine University of Concepción Concepcion Chile

Objective: To compare the long-term results of the treatment of mild acute biliary pancreatitis in patients with gallbladder in situ, without stones in the bile duct, treated by cholecystectomy, and endoscopic sphincterotomy (ES) versus simple cholecystectomy in the prevention of recurrence of this pathology. Material and Methods: Between May 2008 and December 2012, 110 consecutive patients with a mild acute biliary pancreatitis (ABP) were prospectively studied. None had undergone cholecystectomy, and choledocholithiasis was ruled out by ERCP. Two groups of patients were created and randomized: Group I (n = 55) who underwent ERCP plus ES and Group II (n = 55) only had diagnostic ERCP. Patients were then referred for cholecystectomy. Follow up was completed in 101 patients. Group I was made up of 53 patients and Group II had 48 similar characteristics. Patients were followed for an average of 105 months. At the end of the follow-up, 12 (22.6%) from Group I and 6 (12.5%) from Group II (p = 0.143) remained with the gallbladder in situ. Resultsmily:Verdana;">: There were 53 patients in Group I (100%). Only 42 (87.5%) of those in Group II evolved without biliopancreatic complications (p = 0.0096). In the latter, 6 (12.5%) wer

关键词： Pancreatitis Endoscopic Sphincterotomy

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Food and Nutritional Insecurity before and during the COVID-19 Pandemic in Households of Women Belonging to a Social Program

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Food and Nutrition Sciences 2021年第7期12卷 742-758页

作者： monserrat méndez-Pérez Rebeca monroy-Torres Silvia Delgado-Sandoval Karen medina-Jiménez Laboratorio de Nutrición Ambiental y Seguridad Alimentaria. Departamento de medicina y Nutrición Universidad de Guanajuato Campus León Leon Mexico Observatorio Universitario de Seguridad Alimentaria y Nutricional del Estado de Guanajuato Leon Mexico División de Ciencias de la Salud e Ingenierías Universidad de Guanajuato Campus Celaya-Salvatierra Celaya México

Introduction: According to the National Health and Nutrition Survey, the mexican households in 2018 had food insecurity at 55.5% while in 2012 it was 70%. Food insecurity is a global health problem and now with the CO... 详细信息

Introduction: According to the National Health and Nutrition Survey, the Mexican households in 2018 had food insecurity at 55.5% while in 2012 it was 70%. Food insecurity is a global health problem and now with the COVID-19 pandemic, it has increased. Objective: To compare the levels of food and nutritional insecurity in women’s households from two Social Impulse Centers of the Secretary for Human Social Development (SEDESHU) before and during the COVID-19 pandemic. Methods: A comparative and cross-sectional study was carried out in 41 women participating in a nutritional intervention program in two social promotion centers. Food security was measured with the Latin American and Caribbean Food Security Scale (ELCSA), comparing it in a period from January to April 2020: before and during the health contingency. Socio-economic and demographic variables were also measured, as well as access to water during the COVID-19 pandemic. Results: Food insecurity levels during the COVID-19 contingency were found to have increased by more than 60% (from 31.7% to 93%);the main risk factors associated with unemployment and access to healthy food. The COVID-19 contingency reflects impacts on households, but because women participated in the nutritional intervention program, it could influence by observing that, at least, the use of food was adequate since apparently food waste was minimal. mil

关键词： Food Insecurity Access Water Loss Employment COVID-19 Social Pro-grams

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