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The aim of this work was to assess effect of saturated constructed wetland-Microbial fuel cell system on dissolved oxygen gradient, electricity generation and ammonium removal. Two laboratory-scale systems, one planted with Schoenoplectus californicus (SCW1-MFC) and other without plant (SCW2-MFC), were fed discontinuously with synthetic wastewater over 90 days. Both systems were operated at different organic loading rate (12 and 28 g COD/m2d) and ammonium loading rate (1.6 and 3.0 g NH4+- N/m2 d) under open circuit and close circuit mode. The results indicate that between lower and upper zones of wetlands the average values were in the range of 1.22 ± 0.32 to 1.39 ± 0.27 mg O2/L in SCW1-MFC and 1.28 ± 0.24 to 1.56 ± 0.31 mg O2/L in SCW2-MFC. The effect of operating mode (closed and open circuit) and vegetation on DO was not significant (p > 0.05). Chemical oxygen demand (COD) removal efficiencies, fluctuated between 90 and 95% in the SCW1-MFC and 82 and 94% in the SCW2-MFC system. Regarding NH4+- N, removal efficiencies were above 85% in both systems reaching values maximus 98%. The maximum power density generated was 4 and 10 mW/m2 in SCW1-MFC, while SCW2-MFC recorded the highest values (12 and 22 mW/m2).

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One of the environmental challenges that is currently negatively affecting the ecosystem is the continuous discharge of untreated industrial waste into both water sources and soils. For this reason, one of the objectives of this qualitative study of exploratory-descriptive scope was the review of scientific articles in different databases-Scopus, Web of Science, and Science Direct-published from 2010 to 2021 on the use of fruit peels as a sustainable waste in the removal of heavy metals present in industrial wastewater. For the selection of articles, the authors used the PRISMA guide as a basis, with which 210 publications were found and 93 were compiled. Considering the reported work, a content analysis was carried out using NVivo 12 Plus and VOSviewer 1.6.17 software. The results show that the fruits mentioned in these publications are lemon, banana, mango, tree tomato, pineapple, passion fruit, orange, coconut, avocado, apple, lulo, and tangerine. However, no studies were found with lulo and tree tomato peels. On the other hand, the heavy metals removed with the selected fruit peels were Pb+2, Cr+3, Cr+6, Ni+2, Cd+2, As+5, Cu+2, and Zn+2.

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Some of the diverse agro-industrial waste generated in primary or secondary stages have proved to be promising biomaterials for treating aqueous effluents contaminated, in this case, with heavy metals. Therefore, it is necessary to know their optimal operating conditions and the regeneration or reusability of the solid by-product, an aspect related to desorption. Considering the above, this article presents the findings of a preliminary study related to the desorption process of coffee pulp without physicochemical modification (Castilla variety), an agricultural waste used as a sorbent of Cr(III and VI) ions in synthetic wastewater. The desorption efficiency of four eluting agents at defined concentrations (0.10M)-HC1, HNO3, H2SO4, and EDTA-was evaluated in a time interval of 1 to 9 days. Likewise, the proposals for the sorption and/or desorption mechanisms proposed and reported in the literature with respect to the use of biosorbents derived from the coffee crop are presented. With respect to the results, the coffee pulp used in previous studies of the adsorption of chromium species mentioned (optimal conditions in synthetic water of particle size 180 µm, dose 20 g·L-1, agitation 100 RPM, room temperature, time of 90 to 105 min) showed efficiencies in the removal of Cr(III) and Cr(VI) of 93.26% and 74.80%, respectively. Regarding the extracting substances used, H2SO4 0.10 M was the one that presented the highest desorption percentage in both chromic species, with a desorption of 45.75% Cr(VI) and 66.84% Cr(III) in periods of 5 and 9 days, respectively, with agitation of 100 RPM and room temperature. Finally, the dissemination of preliminary results on the desorption of coffee pulp contaminated with chromic species without physicochemical modification is novel in this study, as similar work with this specific material has not yet been reported in the literature. On the other hand, the limitations of the study and future research are related to the evaluation at different concentrations and of other extractor solutions that allow improving the efficiency of desorption of these chemical species in a shorter time from the coffee pulp (with and without modification) as well as the reuse cycles. As a result, the desorption of coffee pulp used as an adsorbent material in real water could help researchers identify the possible interfering factors that affect the process (foreign anions and cations, organic matter, environmental conditions, among others).

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Gastric cancer (GC) is a leading cause of cancer death in Chile. Although recommended in international guidelines since 2006, perioperative chemotherapy was not available to patients in the public health system in Chile until 2016. We conducted an observational study to assess the feasibility of this strategy in public hospitals in Chile (Observational Study of Perioperative Chemotherapy in Locally Advanced Gastric Cancer - PRECISO). Patients with locally advanced, operable GC were offered to receive preoperative chemotherapy with Epirubicin + Cisplatin + Capecitabine (ECX) for three cycles followed by curative surgery. Staging included abdominal CT scan and laparoscopy if peritoneal carcinomatosis was suspected. Postoperative ECX for three cycles was recommended. Between August 2010 and March 2013, 110 patients were screened and 61 enrolled. Median age was 62 years (23-76 years) and most patients had good performance status at baseline (Eastern Cooperative Oncology Group performance status score (ECOG) 0: 42, ECOG 1: 19). Tumour site was proximal in 32 (52%) and medial and distal in 29 (48%) patients. All but four patients (n = 57, 93%) completed three cycles of preoperative chemotherapy. Fifty-six patients were operated and 54 (89%) had a curative resection. Thirty-three patients (54%) had pT0-2, and 18 (30%) had pN0 tumours, with two patients achieving a complete response. As of 20 December 2020, 39 patients died, 32 due to GC, one within 30 days of surgery, two due to intestinal obstruction at 5 and 3 months after surgery and four due to other causes. Five-year survival rate was 38%. We conclude that perioperative chemotherapy is feasible in public hospitals in Chile and should be offered to patients with locally advanced GC.

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BACKGROUND: Helicobacter pylori (HP) is the most widespread chronic human infection worldwide and the most important pathogenic factor of gastric cancer. The calculated prevalence at the Clinical Hospital of the University of Chile from 2002 to 2005 was 44.9%. AIM: To determine the current prevalence of HP in patients undergoing an upper gastrointestinal endoscopy (UGI) and analyze its distribution according to age and endoscopic findings. MATERIAL AND METHODS: We reviewed 3.433 UGI performed during the year 2015, selecting those in which rapid urease test (RUT) was done. A positive RUT or a positive gastric biopsy (GB) were considered as HP infection. RESULTS: RUT was done in 1862 UGI (55%) performed in patients aged 51 ± 17 years, (66% women). In 23% of these endoscopies, the RUT was positive. A GB was obtained 43% of endoscopies and 30% were positive for HP. In 105 patients the RUT was negative and the GB positive (rendering a 19.5% false negative rate). HP was detected by RUT and GB in 29% of endoscopies. The highest prevalence of infection (38.1%) was found between 40 and 49 years. HP infection had odds ratio of 4.24 for nodular gastropathy, 2.63 for gastric ulcer and 2.14 for duodenal ulcer (p < 0.05). CONCLUSIONS: HP prevalence in our center decreased significantly from 44.9% to 28.9% in 11 years. False negative RUT results may bias this finding. The use of proton pump inhibitors and antimicrobials that can interfere with the detection of HP should be registered to properly analyze the results of the RUT.

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INTRODUCCIÓN: El dolor lumbar crónico genera alta disfuncionalidad, su tratamiento es complejo y en algunos casos se presenta refractariedad a tratamientos convencionales. El síndrome de sensibilización central por dolor lumbar involucra presencia de síntomas ansiosos, depresivos, trastorno del sueño, fatiga, alteraciones del apetito y disfuncionalidad en actividades de la vida diaria. El manejo del dolor lumbar crónico con síndrome de sensibilización central es dificultoso, requiere de intervenciones multidimensionales y esquemas farmacológicos atípicos. OBJETIVO: Se describe el uso de topiramato como fármaco coadyuvante en el manejo de pacientes con dolor lumbar crónico resistente a tratamiento standard en 25 pacientes. MATERIALES Y MÉTODO: Seguimiento a 12 semanas y evaluación de funcionalidad, sintomatología ansiosa-depresiva, control del dolor y fatiga a través de múltiples escalas. Resultados: La dosis mediana fue de 300mg. El 72 por ciento (18 pacientes) presenta mejoría estadística en síntomas angustiosos, depresivos, sueño, EVA de dolor y fatiga y funcionalidad. Solo el 16 por ciento (4 pac) presentan reacciones adversas que obligan a suspensión del fármaco. El 12 por ciento (3 pacientes) no presentaron respuesta terapéutica. DISCUSIÓN: El topiramato podría ser una opción coadyuvante para el manejo del síndrome de dolor lumbar crónico con síndrome de sensibilización central.

INTRODUCTION: The chronic low back pain causes severe dysfunction, treatment is complex and in some cases it can be refractory to usual treatment. Central Sensitivity syndrome secondary to chronic low back pain is characterized by anxious, depressive, sleep disorders, fatigue, eating disorders and damage in daily activities life. Management of this syndrome must be integrative and multidimensional. OBJECTIVES: Describe the use of topiramate in 25 patients with chronic low back pain for pain relief in refractory patients to standard treatment, during 12 weeks. MATERIALS AND METHODS: Following during 12 weeks, multiples Assessments about anxiety, depression, functionality, sleep quality, VAS pain and fatigue. Results: Median doses 300mg. 72 percent got pain relief, and decrease in anxious depressive symptoms, improve sleep quality, daily function. 16 percent didn't get pain relief and suffered adverse effects forcing suspension of the drug. 12 percent didn't get pain relief without adverse effects. DISCUSSION: Topiramate might be a treatment option for pain relief in these patients.

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Background and aims The prevalence of chronic non-cancer pain has not been specifically reported in Chile. Methods In order to assess its prevalence and impact, we designed a tool based on previously published survey studies. We analyzed a sample of 784 subjects to determine the prevalence of chronic non-cancer pain, with a maximum variability of 50%, a confidence interval (CI) of 95%, and an estimation error of 3.5%. Finally, a cross-sectional cell phone survey was conducted on a nationally representative probability sample of 865 subjects of over 18 years, in November 2013. The prevalence of chronic non-cancer pain was estimated by using expansion factors according to national projections by age group and gender, from the Chilean National Institute of Statistics for the year 2010. Results The estimated prevalence of chronic non-cancer pain was 32.1% (95% CI: 26.5-36.0). The respondents with chronic non-cancer pain presented the following results: 65.7% had moderate pain, and 20.8%, severe pain; 65.6% had somatic pain, 31.7% neuropathic pain, and 2.7% visceral pain. Approximately 70% reported they were receiving some kind of pharmacological treatment with certain frequency. In 64.9%, medication was prescribed by a physician. The prevalence of sick leave in workers was 30.22%, with a median duration of 14 days (interquartile range: 14; range: 1-60). Conclusions Chronic non-oncological pain occurs in 32% of Chilean adults. These figures provide the first measurement of chronic non-cancer pain in the Chilean population. Implications Chronic non-oncological pain impact as a public health problem is revealed, given the high prevalence found, and the elevated private and social costs involved.

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Background: Helicobacter pylori (HP) is the most widespread chronic human infection worldwide and the most important pathogenic factor of gastric cancer. The calculated prevalence at the Clinical Hospital of the University of Chile from 2002 to 2005 was 44.9%. Aim: To determine the current prevalence of HP in patients undergoing an upper gastrointestinal endoscopy (UGI) and analyze its distribution according to age and endoscopic findings. Material and Methods: We reviewed 3.433 UGI performed during the year 2015, selecting those in which rapid urease test (RUT) was done. A positive RUT or a positive gastric biopsy (GB) were considered as HP infection. Results: RUT was done in 1862 UGI (55%) performed in patients aged 51 ± 17 years, (66% women). In 23% of these endoscopies, the RUT was positive. A GB was obtained 43% of endoscopies and 30% were positive for HP. In 105 patients the RUT was negative and the GB positive (rendering a 19.5% false negative rate). HP was detected by RUT and GB in 29% of endoscopies. The highest prevalence of infection (38.1%) was found between 40 and 49 years. HP infection had odds ratio of 4.24 for nodular gastropathy, 2.63 for gastric ulcer and 2.14 for duodenal ulcer (p < 0.05). Conclusions: HP prevalence in our center decreased significantly from 44.9% to 28.9% in 11 years. False negative RUT results may bias this finding. The use of proton pump inhibitors and antimicrobials that can interfere with the detection of HP should be registered to properly analyze the results of the RUT.

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Resumen Introducción: La biorremediación, se ha convertido en una alternativa atractiva y prometedora a las tradicionales técnicas físico-químicas para la remediación de los compuestos que contaminan el ambiente. Objetivo: Revisión sobre la aplicación de la biorremediación y su aporte en el al cumplimiento de uno de los objetivos de desarrollo sostenible. Materiales y métodos: Estudio descriptivo mediante la revisión documental sobre las posibilidades y limitaciones que presenta esta biotecnología en el tratamiento de problemas de contaminación. Resultados: Entre las principales tecnologías que se han registrado desde la década de 1970, la biorremediación ha demostrado ser rentable y eficiente en la remoción de determinados contaminantes. Conclusión: A pesar de los beneficios de las tecnologías de biorremediación, existen algunas dificultades en la aplicación debido a las restricciones impuestas por el sustrato y variabilidad ambiental, el potencial limitado de biodegradación y la viabilidad de los microorganismos de origen natural, entre otras.

Abstract Introduction: Bioremediation is an alternative to traditional physico-chemical techniques for the remediation of compounds that pollute the environment. Objective: To review the application of bioremediation and its contribution to the fulfillment of one of the objectives of sustainable development. Materials and methods: A descriptive study was made by means of documentary review about the possibilities and limitations of biotechnology in the treatment of problems of contamination. Results: Among the main technologies that have been registered since the decade of 1970, bioremediation has proven to be profitable and efficient in the removal of certain pollutants. Conclusions: Despite the benefits of bioremediation technologies, there are some difficulties in the application due to the restrictions imposed by the substrate and environmental variability, the limited potential of biodegradation and the viability of microorganisms of natural origin, among others.

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Resumen Introducción: Este artículo considera una propuesta de un modelo de aprovechamiento de residuos sólidos orgánicos para el departamento de Cundinamarca, el cual responde a la necesidad de una herramienta que apoye en la toma de decisiones para la planificación y gestión de los residuos sólidos orgánicos. Objetivo: Realizar una aproximación de un modelo de optimización conceptual, técnico y matemático para el apoyo en la toma de decisiones con el fin de minimizar impactos ambientales. Materiales y métodos: El tipo de investigación aplicada en este trabajo se considera descriptiva, dado que se presentan algunas características fundamentales del fenómeno homogéneo estudiado y se considera adicionalmente cuasi experimental. El cálculo del modelo para plantas del departamento está basado en tres ejes (ambiental, económico y social), presentes en la ecuación general de optimización. Resultados: Se obtiene un modelo de aprovechamiento de residuos sólidos orgánicos en las técnicas de tratamiento biológico de compostaje aeróbico y lombricultivo, optimizando el sistema con el ahorro de emisiones de gases efecto invernadero emitidos a la atmósfera, y en la reducción total del costo de disposición final de residuos sólidos orgánicos en relleno sanitario. Basándose en el principio económico de utilidad que determina la viabilidad ambiental y sostenibilidad en las plantas de aprovechamiento de residuos sólidos orgánicos para el departamento, los abonos orgánicos como el compost y humus capturan carbono e nitrógeno que reducen las toneladas de CO2.

Abstract Introduction: This article considers a proposal of a model of use of organic solids waste for the department of Cundinamarca, which responds to the need for a tool to support decision-making for the planning and management of organic solids waste. Objective: To perform an approximation of a conceptual technical and mathematician optimization model to support decision-making in order to minimize environmental impacts. Materials and methods: A descriptive study was applied due to the fact that some fundamental characteristics of the studied homogeneous phenomenon are presented and it is also considered to be quasi experimental. The calculation of the model for plants of the department is based on three axes (environmental, economic and social), that are present in the general equation of optimization. Results: A model of harnessing organic solids waste in the techniques of biological treatment of composting aerobic and worm cultivation is obtained, optimizing the system with the emissions savings of greenhouse gases spread into the atmosphere, and in the reduction of the overall cost of final disposal of organic solids waste in sanitary landfill. Based on the economic principle of utility that determines the environmental feasibility and sustainability in the plants of harnessing organic solids waste to the department, organic fertilizers such as compost and humus capture carbon and nitrogen that reduce the tons of CO2.

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