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Optimal Desig. of Hybrid Microg.id in Isolated Communities of Ecuador

Journal of Modern Power Systems and Clean Energ. 2024年第2期12卷 488-499页

作者： luis A.Pesantes Ruben Hidalg.-León Johnny Reng.fo Mig.el torres Jorg. Arag.ndi JoséCordova-g.rcia luis F.Ug.rte Facultad de Ing.niería en Electricidad y Computación of Escuela Superior Politécnica del Litoral(ESPOL)University GuayaquilEcuador Department of Electrical Eng.neering.at Universidad Técnica Federico Santa María SantiagoChile IEEE

In rural territories, the communities use energ. sources based on fossil fuels to supply themselves with electricity, which may address two main problems: g.eenhouse g.s emissions and hig. fuel prices. Hence, there is an opportunity to include renewable resources in the energ. mix. This paper develops an optimization model to determine the optimal sizing. the total annual investment cost in renewable g.neration, and other operating.costs of the components of a hybrid microg.id. By running.a k-means clustering.alg.rithm on a meteorolog.cal dataset of the community under study, the hourly representative values become input parameters in the proposed optimization model. The method for the optimal desig. of hybrid microg.id is analyzed in six operating.scenarios considering.(1) 24-hour continuous power supply;(2) load shedding.percentag.;(3) diesel power g.nerator(g.nset) curtailment;(4) the worst meteorolog.cal conditions;(5) the use of renewable energ. sources including.battery energ. storag. systems(BESSs);and(6) the use of g.nset. A mathematical prog.amming.lang.ag.(AMPL) tool is used to find solutions of the proposed optimization model. Results show that the total costs of microg.id in the scenarios that cover 100% of the load demand(without considering.the scenario with 100% renewables) increase by over 16% compared with the scenario with g.nset operation limitation. For the desig.s with power supply restrictions, the total cost of microg.id in the scenario with load shedding.is reduced by over 27% compared with that without load shedding.

关键词： Battery energ. storag. system(BESS) isolated community microg.id renewable energ. optimization

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Influence of biomass burning.on ozone levels in the Meg.lopolis of Central Mexico during.the COVID-19 lockdown

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Journal of Environmental Sciences 2024年第9期143卷 99-115页

作者： Victor Almanza luis g.rardo Ruiz-Suárez Ricardo torres-Jardón Ag.stín g.rcía-Reynoso Iván Y.Hernández-Paniag.a Institute for Atmospheric Sciences and Climate Chang. National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropog.nic emissions resulting.from the COVID-19 lockdown provided a unique opportunity to evaluate the effect of mitig.tion measures aiming.to abate air pollution.In Mexico,the total lockdown period took place during.the dry-hot season when biomass burning.activity is enhanced.Here,we investig.te the role of biomass burning.emissions on reg.onal ozone levels in the Meg.lopolis of Central Mexico.The studied period covers the lockdown phases 2 and 3,and the first month of the New Normal.We applied a factor separation technique and process analysis to estimate the pure and synerg.stic contributions of emission reductions under lockdown and that from biomass burning.to daily ozone maximum concentrations in 7 metropolitan areas of different states in the Meg.lopolis.The results revealed that biomass burning.plumes likely masked the effect of massive reductions from mobile emissions,impacted the PBL development during.phase 3 and favored transition and mixed NO_(x)-limited and VOC-limited reg.onal reg.mes.This contributed to increased ozone production in the middle to lower PBL by chang.ng.the reg.onal backg.ound levels which potentially could bias hig. ozone production efficiency estimations.g.ven the Meg.lopolis contribution to economic and societal development at national scale,our study sug.ests that ozone mitig.tion measures during.the dry-hot season targ.ting.mainly mobile emissions will likely be offset by biomass burning.plumes.A reg.onal and synerg.c policy aiming.to control biomass burning.would help to reduce the occurrence of hig. ozone levels in Central Mexico with the co-benefit of tackling.short-lived climate pollutants.

关键词： COVID-19 Mexico Meg.lopolis Ozone Factor Separation Process Analysis

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Use of two-surfactants mixtures to attain specific HLB values for assisted TPH-diesel biodeg.adation

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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 Ing.niería 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.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. 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 biodeg.adation process, the choice of surfactant(s) is of crucial importance. The question is: does the type of surfactant(i.e. chemical family) affect the biodeg.adation 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 g.t a wide rang. of specific HLB values. Tween20 and Span20 were mixed in the appropriate proportions to g.t 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 biodeg.adation was measured at the beg.nning. and after 8 weeks, as well as the FCU/g. soil, as a measure of microorg.nisms′ development during.the biodeg.adation period. A second aim of this work was to assess the use of g.ar g.m as a biodeg.adation 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 biodeg.adation rate. Surfactant's synerg.sm was clearly observed. Reg.rding.the use of g.ar g.m, no biodeg.adation 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 g.m concentration increased. It is quite possible that g.ar g.m was used as a microbial substrate.

关键词： ag.d soils enhanced bioremediation HLB mixtures Tween Span surfactants

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Colon Adenocarcinoma in a Retrog.ade Intussusception: A Case Report and Literature Review

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Open Journal of g.stroenterolog. 2024年第5期14卷 153-160页

作者： Carlos Hernández Brito Pedro Arredondo Ruiz Brenda Paola Sáenz Dávila Arsenio torres Delg.do luis Eduardo Méndez Turrubiates luis Áng.l Amezcua Toledo Omar Josué Herrera López Surg.cal Oncolog. Department Centro Oncol&#243gico Onkolid Veracruz Mexico Clinical Oncolog. Department Centro Oncol&#243gico Onkolid Veracruz Mexico g.neral and Laparoscopic Surg.ry Corporativo M&#233dico-Quir&#250rgico Torres Veracruz Mexico Radiation Oncolog. Department Centro Oncol&#243gico Onkolid Veracruz Mexico Radiolog. Department Centro Oncol&#243gico Onkolid Veracruz Mexico Anatomical Patholog. Department Centro Oncol&#243gico Onkolid Veracruz Mexico

Backg.ound: Intussusception is defined as a telescoping.of a proximal g.strointestinal seg.ent with its mesentery to a distal one, only 5% occur in adults and in colon the probability that it is caused by a malig.ant disease is up to 65%. Only 1% occurs in a retrog.ade manner, the rest occur in an anterog.ade manner. Aim: Describe the clinical presentation of an intussusception in the adult patient as well as its most frequent causes and possible complications that influence decision making.for a definitive treatment. Case Presentation: A 66-year-old woman diag.osed with colon adenocarcinoma who underwent elective transverse colectomy and colonic anastomosis with an incidental finding.of a transverse colon tumor in a retrog.ade intussusception was studied. Conclusion: In any adult patient with an intussusception especially in colon a neoplasia should be suspected and the affected seg.ent should be resected without being.reduced due to the risk of perforation and tumor dissemination.

关键词： Colon Cancer Colon Adenocarcinoma Colonic Intussusception Intussusception

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Use of Prosopis laevig.ta Seed g.m and Opuntia ficus-indica Mucilag. for the Treatment of Municipal Wastewaters by Coag.lation-Flocculation

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Natural Resources 2012年第2期3卷 35-41页

作者： luis g. torres Sandra L. Carpinteyro-Urban Department of Bioprocesses Unidad Profesional Interdisciplinaria de Biotecnología UPIBI-Instituto Politécnico Nacional Mexico

Prosopis laevig.ta and Opuntia ficus-indica g.ow in arid and semiarid reg.ons of Mexico and other countries. Both produce biopolymers with interesting.characteristics from the rheolog.cal point of view as well as because of their coag.lating.flocculating.capabilities. Prosopis produce g.lactomannans inside the endosperm, very similar to those found in g.ar, locust bean, and tara g.ms. Opuntia sp. produces mucilag. that contains polyg.lacturonic acid and five neutral sug.rs. Prosopis seed g.m has not been proposed to be used as coag.lant-flocculant before. In the case of Opuntia mucilag., some authors have sug.ested its use in the treatment of waters, using.either the mucilag. or the whole cladode powder. The use of these products in the treatment of municipal or even industrial wastewaters could g.ve rise to diverse benefits. From the environmental point of view, treated waters with neither Fe nor Al, nor synthetic polymers would be obtained (with less toxicity risk). Besides, the produced sludg.s would be smaller in amount, with better biodeg.adability, and lower metals content. From the economical point of view, the use of these biopolymers would g.ve an added value to the Opuntia and Prosopis culture in Mexico, helping.small communities to enhance their incomes by producing.environmental-friendly products. This work shows that both Prosopis g.lactomannan and Opuntia mucilag. can be used to treat municipal wastewaters with an initial org.nic charg. of about 827 mg.L as COD by the coag.lation-flocculation process, with COD removals for the mesquite seed g.m of up to 90% (pH 10, dose of 75 mg.L) and of 60% (pH 7, doses of 50 and 150 mg.L). In the case of mucilag., 65% of the initial COD was removed at pH 10 (dose of 50 mg.L). These fig.res are very promising.for the treatment of wastewaters, with environmental-friendly products.

关键词： Biopolymers Coag.lation Flocculation Opuntia ficus Mucilag. Prosopis laevig.ta Seed g.m Wastewaters

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Risk Factors Associated with Unsuccessful Vag.nal Birth after One Cesarean (VBAC-1) in Puerto Rico

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Open Journal of Obstetrics and g.necolog. 2024年第6期14卷 888-902页

作者： Irazú g.inan Marjorie Suárez Fabiola Ang.lo luis Mayol Paula Suárez Lisandris Dominicci Nathalie Chang.Saribel torres Antonio Rodríg.ez Raymond L. Tremblay Maricarmen Colón-Díaz Department of Physiolog. and Patholog. San Juan Bautista School of Medicine Caguas USA

Backg.ound: Cesarean section (CS) has increased steadily over the last decade, with an estimated one-third of women delivering.by cesarean section worldwide. Objective: Our study aimed to investig.te the demog.aphic and associated factors influencing.vag.nal birth after one cesarean (VBAC-1) success focusing.on variables like pre-preg.ancy BMI, diabetes, hypertension, education, and smoking. Study Desig. and Methods: In this retrospective study, we analyzed 285 cases (81 unsuccessful VBAC-1, 204 successful VBAC-1) from San Juan City Hospital (Puerto Rico) between January 1, 2019, and December 31, 2020. We used odds ratios and model selection comparison to assess the impact of variables on successful VBAC-1, using.a sig.ificance threshold of 95% CI. Model selection assessed binomial model combinations using.a g.neralized linear approach to identify key risk factors. Results: Unsuccessful VBAC-1 (a repeat cesarean), was associated with diabetes (OR: 0.376, p = 0.086), hypertension (OR: 0.23, p = 0.006), and university-educated women (OR: 1.372, p = 0.711). Hig. school-educated women had an OR of 3.966 (p = 0.105), while overweig.t women were 0.481 times more likely to have unsuccessful VBAC-1 (p = 0.041). Sig.ificant associations were not found with obesity (OR: 0.574, p = 0.122), underweig.t/normal (OR: 1.01, p = 0.810), or smoking.(OR: 1.227, p = 0.990). Conclusion: Results revealed women with hig.er education levels, hypertension, or diabetes are less likely to have a successful VBAC-1. Understanding.the complex interactions affecting.these outcomes is aimed at establishing.g.idelines for healthcare professionals to conduct systematic risk/benefit assessments. This study lays a foundation for evidence-based practices and policies, offering.initial insig.ts into VBAC-1 success factors in Puerto Rico.

关键词： Diabetes Hypertension Obesity Trial of Labor Vag.nal Birth after Cesarean

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Ca-alg.nate spheres behavior in presence of some solvents and water-solvent mixtures

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Advances in Bioscience and Biotechnolog. 2011年第1期2卷 8-12页

作者： luis g. torres Ang.lica Velasquez Marco A. Brito-Arias 不详

Immobilization systems more frequently used are calcium alg.nate spheres. These biocatalysts have many potential applications in the immobilization of enzymes, prokaryotic cells, veg.tal and animal cells, alg.e, org.nelles and mixtures of these living.components. Other applications of immobilized cells imply the use of non aqueous systems. Some bioconversions are carried out in the presence of solvents such as hexane acetone or acetonitrile, or mixtures water-solvents. The aim of this work was to investig.te the behaviour of Ca-alg.nate spheres when put in contact with different solvents (water, diesel, ethanol, methanol, acetone, n-hexane, isopropyl alcohol, THF, acetonitrile, and toluene), or solvent-water mixtures (i.e., ethanol-water), reg.rding.the resistance of the alg.nate spheres after days of contact. Calcium alg.nate particles suffered different damag.s, depending.on the solvent they were put in contact. Water did not damag.d the Ca-alg.nate structure with or without Ca present. On the other hand different solvents lost a proportion of volume, i.e., n-hexane (16%), methanol (19%), ethanol (19.5%), toluene (22%), diesel (34%), acetone (765), isopropyl alcohol (80%), THF and acetonitrile (total loss, total destruction). Nor the dielectric constant nor the polarity indexes were capable of explaining.the difference on the volume loss or total sphere destruction, except for water-ethanol mixtures.

关键词： Dielectric Constant Ca-Alg.nate Immobilization Solvents Spheres Polarity Index

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Endoscopic ultrasound-g.ided g.stroenterostomy for g.stric outlet obstruction in Mexico

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World Journal of Surg.cal Procedures 2024年第3期14卷 15-20页

作者： Massiel Madelin Rosario-Morel Rodrig. Soto-Solis Katia Picazo-Ferrera Miriam Idalia torres-Ruiz JoséAlberto Estradas-Trujillo Mario Alberto g.llardo-Ramírez g.rardo Akram Darwich-del Moral luis Ariel Waller-g.nzález Department of Endoscopy Centro Médico Nacional“20 de Noviembre”ISSSTEMexico City 03229Mexico Department of g.stroenterolog. HospitalÁngeles PedregalMexico City 10700Mexico Department of Endoscopy Centro Médico ABCMexico City 01120Mexico Department of Endoscopy Hospital General de México“Dr.Eduardo Liceaga”Mexico City 06720Mexico

BACKg.OUND Endoscopic ultrasound-g.ided g.stroenterostomy(EUS-g.)has recently emerg.d as an alternative treatment for g.stric outlet obstruction(g.O)in selected patients.AIM To report the initial experience of EUS-g. in patients with g.O.METHODS This study was a retrospective,observational,multicenter study in which the data from 10 patients who underwent EUS-g. due to g.O between September 2021 and May 2023 were collected.We analyzed technical success,clinical success,adverse events,and survival.Technical success was defined as adequate positioning.and deployment of the stent.Clinical success was defined as the patient’s ability to tolerate oral intake without vomiting.7 d after the procedure.Postprocedural adverse events were recorded.RESULTS Eleven procedures in 10 patients with g.O were included.The mean ag. of the patients was 67.5 years(rang.:56-77 years).Malig.ant g.O was present in 9 patients.Technical success was achieved in 9/11 procedures(82%).Among.them,clinical success was achieved in 9 patients(100%).Adverse events occurred in 1 patient(9%).The median survival was 3 months(n=7;rang.:1-8 months).CONCLUSION EUS-g. is a feasible therapeutic option in the treatment of g.O.

关键词： Endoscopic ultrasound-g.ided g.stroenterostomy g.stric outlet obstruction Lumen apposing.metal stent Interventional endoscopic ultrasound g.strojejunostomy Duodenal stenting

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Structural performance assessment of g.RP elastic g.idshells by machine learning.interpretability methods

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Frontiers of Structural and Civil Eng.neering 2022年第10期16卷 1249-1266页

作者： Soheila KOOKALANI Bin CHENg.Jose luis Chavez torres Department of Civil Eng.neering Shanghai Jiao Tong UniversityShanghai 200240China Department of Civil Eng.neering Technical University of LojaLoja 110102Ecuador

The prediction of structural performance plays a sig.ificant role in damag. assessment of g.ass fiber reinforcement polymer(g.RP)elastic g.idshell structures.Machine learning.ML)approaches are implemented in this study,to predict maximum stress and displacement of g.RP elastic g.idshell structures.Several ML alg.rithms,including.linear reg.ession(LR),ridg. reg.ession(RR),support vector reg.ession(SVR),K-nearest neig.bors(KNN),decision tree(DT),random forest(RF),adaptive boosting.AdaBoost),extreme g.adient boosting.Xg.oost),categ.ry boosting.CatBoost),and lig.t g.adient boosting.machine(Lig.tg.M),are implemented in this study.Output features of structural performance considered in this study are the maximum stress as f1(x)and the maximum displacement to self-weig.t ratio as f2(x).A comparative study is conducted and the Catboost model presents the hig.est prediction accuracy.Finally,interpretable ML approaches,including.shapely additive explanations(SHAP),partial dependence plot(PDP),and accumulated local effects(ALE),are applied to explain the predictions.SHAP is employed to describe the importance of each variable to structural performance both locally and g.obally.The results of sensitivity analysis(SA),feature importance of the CatBoost model and SHAP approach indicate the same parameters as the most sig.ificant variables for f1(x)and f2(x).

关键词： machine learning g.idshell structure reg.ession sensitivity analysis interpretability methods

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Surfactant-Enhanced Washing.of Soils Contaminated with Wasted-Automotive Oils and the Quality of the Produced Wastewater

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Journal of Environmental Protection 2013年第12期4卷 1495-1501页

作者： Montserrat Zacarias-Salinas Mabel Vaca Mig.el A. Flores Erick R. Bandala luis g. torres Departamento de Ing.niería Civil y Ambiental Escuela de Ing.niería Universidad de las Américas-Puebla. Sta. Catarina Mártir Cholula Puebla México Laboratorio de Calidad de Ag.a y Residuos Universidad Autónoma Metropolitana-Unidad Azcapotzalco México UPIBI-Instituto Politécnico Nacional. Av. Acueducto s.n. Colonia Barrio la Lag.na Ticomán. México DF México

An old automotive industrial site located at Mexico City with many years of operation and contaminated with heavy oil hydrocarbons, particularly spent oils, was assessed for restoration using.the surfactant enhanced soil washing.(SESW) process. The main g.al of this study was to characterize the contaminated soil in terms of TPHs, BTEX, PAHs, and metals contents as well as microbiolog.cally (total heterotrophs and specific deg.ading.microorg.nisms). We also aimed to determine the surfactant type and concentration to be used in the SESW process for the automotive waste oil contaminated soil. At the end, sixteen kg.of contaminated soil were washed and the produced wastewater (approximately 40 L) was characterized in terms of COD, BOD;solids, and other physico-chemical parameters. The soil contained about 14,000 mg.of TPH/kg.soil (heavy fraction), 0.13 mg.kg.of benzo (k) fluoranthene and 0.07 mg.kg.of benzo (a) pyrene as well as traces of some metals. Metals concentrations were always under the maximum concentration levels sug.ested by Mexican reg.lations. 15 different surfactants were used to identify the one with the capability to achieve the hig.est TPH removal. Surfactants included 5 anionics, 2 zwitterionic, 5 nonionics and 3 natural g.ms. Sulfopon 30 at a concentration of 0.5% offered the best surfactant performance. The TPH removals employing.the different surfactants were in the rang. from 38% to 68%, in comparison to the soil washing.with water (10% of TPH removal). Once the surfactant was selected, 70 kg.of soil were washed and the resulting.water contained approximately 1300 mg.L of COD, 385 mg.L of BOD (BOD/COD = 0.29), 122 mg.L of MBAS, and 212 mg.L of oil and g.eases, among.other contaminants.

关键词： Wasted Automotive Oils Surfactants Soil Washing Waste Water

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