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

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

作者： Victor Almanza Luis Gerardo Ruiz-Suárez Ricardo Torres-Jardón Agustín García-Reynoso iván Y.Hernández-Paniagua Institute for Atmospheric Sciences and Climate Change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the COVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation 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 investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis 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 synergistic 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 Megalopolis.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 regional regimes.This contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency estimations.Given the Megalopolis contribution to economic and societal development at national scale,our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes.A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： COVID-19 Mexico Megalopolis Ozone Factor Separation Process Analysis

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Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems

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Journal of Mountain Science 2024年第1期21卷 33-48页

作者： Francis Levi A.DURAnO Jon Marx SARMIEnTO Larry n.DIGAL Pedro A.ALVIOLA iv School of Management University of the Philippines MindanaoDavao City 8000Philippines

Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation areas.

关键词： Cocoa farms Cobb-Douglas production function Elevation Philippines Stochastic frontier analysis Technical efficiency

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Mental health in organizations from a healthcare analytics framework:taxonomic model,trends,and impact of COVID-19

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Journal of Management Analytics 2024年第1期11卷 62-86页

作者： Jorge iván Pérez Rave Carlos Mario Zapata Jaramillo Gloria Patricia Jaramillo Álvarez IDInnOV research group IDINNOV S.A.SMedellínColombia Department of Computing and Decision Sciences Universidad Nacional de ColombiaMedellínColombia

Mental disorders negatively affect employee well-being and organizational performance.Organizations face a challenge in terms of how to manage mental health.This paper clarifies three issues(underlying patterns,trends,and impact of COVID-19)regarding the scientific study of mental health in organizations from a healthcare analytics framework.The framework comprises eight stages considering a text-driven approach with scientific corpora assisted by linguistic/computational and statistical resources.This study discovers a new taxonomic model comprising five patterns in the scientific discourse on the topic.Trend analyses reveal imbalances and concerns regarding the interests associated with the patterns,which is reinforced by examining patterns“before”and“during”COVID-19.This paper complements psychological/epidemiological studies on mental health in organizations from a healthcare analytics perspective.

关键词： Healthcare analytics healthcare management analytics mental health scientific discourse text analytics taxonomy COVID-19 management analytics

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Empirical Model to Calculate the Thermodynamic Wet-Bulb Temperature of Moist Air

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Engineering（科研） 2014年第9期6卷 500-506页

作者： Melitón Estrada-Jaramillo iván vera-romero José Martínez-Reyes Agustina Ortíz-Soriano Edgar Barajas-Ledesma Trajectory of Educational Innovation University of the Ciénega of Michoacán State Sahuayo México Trajectory of Energy Engineering University of the Ciénega of Michoacán State Sahuayo México

An equation model for calculating the adiabatic temperature of the wet-bulb thermometer has been obtained empirical fit through a meteorological database, specificly a trough relative humidity and air temperature. A comparison of the results of calculations with the use of this equation and from meteorological database was made. The model deducted of the comparison is valid for a dry bulb temperature range of 3°C to 35°C and for relative humidity percentage in a range of 7% to 97%. normalized errors are less than 5.5%. It means a maximum variation of 0.55°C from data. However, this variation from error represents only 3.6% of the data sample. The equation model was satisfactory.

关键词： Wet-Bulb Temperature Equation Dry-Bulb Temperature Relative Humidity Dry Solar Technologies Humidified Gas Turbines

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Degradation of nucleic acids and nucleotides in several conditions with perspectives of retrieval: A review

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Advances in Bioscience and Biotechnology 2014年第1期5卷 36-39页

作者： José Martínez Reyes Lenin Ejecatl Medina Orozco Melitón Estrada Jaramillo iván vera romero Agustina Ortiz Soriano Trajectory of Educational Innovation University of the Ciénega of Michoacán State Sahuayo Méxio Trajectory of Energy Engineering University of the Ciénega of Michoacán State Sahuayo Méxio Trajectory of Food Genomics University of the Ciénega of Mi-choacán State Sahuayo Méxio

Deoxyribonucleic acid (DnA) or oligonucleotides, can be modified in several ways as chemical degradation by electrophilic reaction, attack of radicals, hydrolytic deamination or oxidative damage caused by ionizing radiation. This work discussed these degradation mechanisms, determining the effects on these biomolecules. The actual knowledge about DnA damages only permits partial enzymatic repair treatments.

关键词： DnA Chemical Degradation

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Biogas Estimation as a Basis for the Implementation of an Intermunicipal Landfill: Michoacan, Mexico

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Journal of Environmental Protection 2014年第7期5卷 577-582页

作者： iván vera-romero José Martínez Reyes Claudio C. Espíritu-Barragán Melitón Estrada-Jaramillo Agustina Ortiz-Soriano Lenin E. Medina-Orozco Trajectory of Educational Innovation University of the Cienega of Michoacan State Sahuayo Mexico Trajectory of Energy Engineering University of the Cienega of Michoacan State Sahuayo Mexico Trajectory of Food Genomics University of the Cienega of Michoacan State Sahuayo Mexico

Municipal solid waste (MSW) generated in the municipalities of Sahuayo, Jiquilpan and Venustiano Carranza in Michoacan, is deposited in open dumps becoming hot spots for health and the environment. The total population in the three municipalities is 130,497 habitants, with a per capita waste production estimated in 0.718 kg·hab-1·day-1 (34,203 t·yr-1). The aim of this study was to estimate the formation of biogas for power generation from the decomposition of waste. The model used was the mexican model of biogas (version 2.0), assuming a useful life of 21 years of the landfill at a cost of 0.19 USD per kWh, the average CFE rate for municipal public lighting. Four possible scenarios were evaluated: one optimal recovering 68% of the biogas (10,095 tonnes of methane in 20 years), having a savings concept in electricity of 8,015,252 USD;in the second case (optimistic intermediate), it is assumed that it obtains 61% of biogas (9046 tonnes of methane) with benefits in power generation for 7,159,679 USD;the third case (pessimistic intermediate) estimating 48% of biogas recovered, being captured 7118 tonnes of methane with profits of 5,633,846 USD into electrical energy, the latter case (pessimistic), assuming 40% of biogas recovered, transforming 4672 tonnes of methane resultant in an economic benefit of 3,697,324 USD for electricity generation. The results justify the investment of the landfill and it is a measure to mitigate climate change and disease prevention.

关键词： Municipal Street Lighting Alternative Energy Public Health

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new trends in diagnosis and management of gallbladder carcinoma

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 13-29页

作者： Efstathios T Pavlidis Ioannis n Galanis Theodoros E Pavlidis ^(nd)Propedeutic Department of Surgery Hippokration General HospitalSchool of MedicineAristotle University of ThessalonikiThessaloniki 54642Greece

Gallbladder(GB)carcinoma,although relatively rare,is the most common biliary tree cholangiocarcinoma with aggressiveness and poor prognosis.It is closely associated with cholelithiasis and long-standing large(>3 cm)gallstones in up to 90%of cases.The other main predisposing factors for GB carcinoma include molecular factors such as mutated genes,GB wall calcification(porcelain)or mainly mucosal microcalcifications,and GB polyps≥1 cm in size.Diagnosis is made by ultrasound,computed tomography(CT),and,more precisely,magnetic resonance imaging(MRI).Preoperative staging is of great importance in decisionmaking regarding therapeutic management.Preoperative staging is based on MRI findings,the leading technique for liver metastasis imaging,enhanced three-phase CT angiography,or magnetic resonance angiography for major vessel assessment.It is also necessary to use positron emission tomography(PET)-CT or ^(18)F-FDG PET-MRI to more accurately detect metastases and any other occult deposits with active metabolic uptake.Staging laparoscopy may detect dissemination not otherwise found in 20%-28.6%of cases.Multimodality treatment is needed,including surgical resection,targeted therapy by biological agents according to molecular testing gene mapping,chemotherapy,radiation therapy,and immunotherapy.It is of great importance to understand the updated guidelines and current treatment options.The extent of surgical intervention depends on the disease stage,ranging from simple cholecystectomy(T1a)to extended resections and including extended cholecystectomy(T1b),with wide lymph node resection in every case or iv-V segmentectomy(T2),hepatic trisegmentectomy or major hepatectomy accompanied by hepaticojejunostomy Roux-Y,and adjacent organ resection if necessary(T3).Laparoscopic or robotic surgery shows fewer postoperative complications and equivalent oncological outcomes when compared to open surgery,but much attention must be paid to avoiding injuries.In addition to surgery,novel targeted treatment along with immunotherapy and recen

关键词： Biliary tract neoplasms Extrahepatic cholangiocarcinoma Gallbladder carcinoma Gallbladder diseases Biliary tree diseases Gastrointestinal malignancies

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Standardizing MI-TLIF, a Proposal for a Reproducible Technique

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Open Journal of Modern neurosurgery 2024年第2期14卷 91-103页

作者： iván Ulises Sámano López Jesús Alberto Pérez Contreras Emmanuel Cantú Chávez Diana Chávez Lizárraga Ana Sofía Peña Blesa Thania Karina Gutiérrez Anchondo Á ngeles Pedregal Ciudad de México México

Background: Minimally invasive transforaminal lumbar interbody fusion (MI TLIF) is a widely known and performed technique, however its versatility among different physicians continues to hinder its replication and results. Therefore, this study aimed to provide a step-by-step surgical guide to perform a safe MI-TLIF, based on the results obtained in patients operated on by a single surgeon over a period of 12 years. Patients and methods: A retrospective, single center, longitudinal, and observational cohort study was conducted with 931 patients who underwent MI TLIF by a single surgeon between 2010 and 2022 using the technique described on this paper, each with a minimum follow-up of 12 months. Criteria included Schizas classification, listhesis according to Meyerding classification, number of levels treated, cage size, and complications (screw repositioning or cerebrospinal fluid leak). Patient clinical outcomes were assessed using the Oswestry Disability Index (ODI), Visual Analog Scale (VAS) for pre- and postoperative radicular pain. Thin slice CT scans were used to assess the progression of the fusion using the Bridwell classification. In the statistical analysis, percentages, median, and interquartile range (IQR) were calculated. Results: nine hundred and thirty one patients underwent MI TLIF using the technique described, eight hundred and eighty (94.5%) had a single level treated and fifty one (5.5%) had a 2 level procedure (982 levels), an 8mm cage was placed on five hundred and seventeenlevels (52.7%), six hundred and sixty three levels(67.6%) achieved grade I fusion, two hundred and sixty six levels (27.1%) achieved grade II fusion, 52 levels (5.3) achieved grade III fusion and one level (0.1) achieved a grade iv fusion or non-union. Revision surgery was performed on 3 patients (0.3%) for screw repositioning, cerebrospinal fluid leak was present on 2 patients during surgery and treated before closure. VAS scores and ODI were improved at 12 months postop (VAS from 8.70 to 2.30 and ODI from 34.2 to 14.1,

关键词： MITLIF Lumbar Interbody Fusion Technique Pain Relief and Disability

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Management of obstructed colorectal carcinoma in an emergency setting:An update

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 598-613页

作者： Efstathios T Pavlidis Ioannis n Galanis Theodoros E Pavlidis 2nd Propedeutic Department of Surgery Hippokration General HospitalSchool of MedicineAristotle University of ThessalonikiThessaloniki 54642Greece

Colorectal carcinoma is common,particularly on the left side.In 20%of patients,obstruction and ileus may be the first clinical manifestations of a carcinoma that has advanced(stage II,III or even iv).Diagnosis is based on clinical presentation,plain abdominal radiogram,computed tomography(CT),CT colonography and positron emission tomography/CT.The best management strategy in terms of short-term operative or interventional and long-term oncological outcomes re-mains unknown.For the most common left-sided obstruction,the first choice should be either emergency surgery or endoscopic decompression by self-expen-dable metal stents or tubes.The operative plan should be either one-stage or two-stage resection.One-stage resection with on-table bowel decompression and irrigation can be accompanied or not accompanied by proximal defunctioning stoma(colostomy or ileostomy).Primary anastomosis is more convenient but has increased risks of anastomotic leakage and morbidity.Two-stage resection(Hart-mann’s procedure)is safer and the most widely used despite temporally affecting quality of life.Damage control surgery in high-risk frail patients is less frequently performed since it can be successfully substituted with endoscopic stenting or tubing.For the less common right-sided obstruction,one-stage surgical resection is more beneficial than endoscopic decompression.The role of minimally invasive surgery(laparoscopic or robotic)is a subject of debate.Emergency laparoscopic-assisted management is advantageous to some extent but requires much expertise due to inherent difficulties in dissecting the distended colon and the risk of rup-ture and subsequent septic complications.The decompressing stent as a bridge to elective surgery more substantially decreases the risks of morbidity and mortality than emergency surgery for decompression and has equivalent medium-term overall survival and disease-free survival rates.Its combination with neoadjuvant chemotherapy or radiation may have a positive effect on long-term oncological outcomes

关键词： Acute abdomen Obstructive ileus Colorectal carcinoma Emergency surgery Colectomy Intraluminal metal stents

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Academic Stress Assessment Using Virtual Reality as an Educational Tool in Spine Surgery

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Open Journal of Modern neurosurgery 2024年第2期14卷 114-123页

作者： Diana Chávez Lizárraga Jesús Alberto Pérez Contreras Fernando Alvarado Gómez Evelyn Quintero Medina Emmanuel Cantú Chávez iván Ulises Sámano López Ana Sofía Peña Blesa Department of neurosurgery ángeles Pedregal Ciudad de México México Department of Traumatology and Orthopedics Hospital Santa Fe Bogotá Colombia

Introduction: The evaluation of academic stress in medical students and residents is a topic of significant interest, given the considerable challenges they face during their learning process with traditional teaching methods. The use of technologies like virtual reality presents an opportunity to enhance their skills through simulations and training. The main objective of this study is to qualitatively assess the stress levels experienced by medical students and residents by integrating virtual reality into their current learning methods, aiming to improve their ability to manage stressors in their practice. Material and Methods: A questionnaire was conducted with 12 medical students and 12 Traumatology and orthopedics residents. The purpose of the questionnaire was to evaluate the levels of academic stress using the SISCO inventory. The stress levels were calculated by transforming average values into percentages, and the following criteria were assigned: 0 to 33% for Mild Stress, 34 to 66% for Moderate Stress, and 67 to 100% for Deep Stress. Then, a virtual reality class focused on spine surgery was provided. Both medical students and residents were trained using the non nocere SharpSurgeon software platform and Oculus Quest 2 virtual reality glasses. At the end of the session, a second questionnaire related to the practice with virtual reality was conducted with the same evaluation criteria and a comparative analysis was carried out. Results: 12 undergraduate students from Hospital Angeles Mexico, CDMX and 12 traumatology and orthopedics residents at Hospital Santa Fe, Bogota were evaluated. The students in CDMX reported an average qualitative stress of 28.50% during habitual practices, which decreased to an average of 14.67% after virtual reality practice. Residents in Bogotá experienced an average qualitative stress of 30.50% with their current learning methods but this reduced to an average of 13.92% after using virtual reality. These findings indicate that the use of virtual reality has a positive impact

关键词： Virtual Reality Academic Stress Learning Strategies Spine Surgery Training

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