45 research outputs found

    Equipamiento ecoeficiente energético integrado al diseño arquitectónico del mercado minorista modelo de Chimbote - 2018

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    La presente investigación tuvo como propósito demostrar los beneficios del equipamiento ecoeficiente energético aplicada al diseño arquitectónico del mercado minorista modelo, mediante celdas fotovoltaicas multicristalinas aplicado en la cobertura de la edificación, mejorando el confort Térmico y haciéndolo energéticamente eficiente al edificio. La conversión de la radiación solar en electricidad sin partes móviles y sin combustible adicional, es una de las características que la hacen insustituible, reduce los costos de electricidad y es amigable con el medio ambiente. Para este proyecto se seleccionó un diseño de investigación de tipo descriptiva y con una propuesta de diseño no experimental, asimismo Transversal. El resultado esperado de esta solución fue eficiente, demostrando la factibilidad de un proyecto de este tipo en la ciudad favoreciendo el desarrollo económico, tecnológico, social y ambiental, dando de esta forma a la ciudad, una identidad cultural, reforzando su historia, tradición y costumbres, que permanecerá y será parte de la memoria colectiva de la población y visitantes. Dando respuestas favorables a las problemáticas, tanto en los aspectos económicos, tecnológicos, sociales y medio ambientales, tales como un excesivo consumo eléctrico, por la falta de conocimiento del potencial energético de la luz solar, aplicado adecuadamente en la arquitectura, por la falta de interés de nuestros gobernantes hacia la ecoeficiencia.Tesi

    Short-term amiodarone therapy after reversion of persistent atrial fibrillation reduces recurrences at 18 months

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    Background: The aim of this study was to compare the outcome of 3 months vs. 18 months of amiodarone treatment after atrial fibrillation (AF) conversion in patients who experienced the first episode of persistent AF. Methods: We included 51 patients who experienced the first episode of persistent AF receiving amiodarone (600 mg) daily for 4–6 weeks. If AF persisted, electrical cardioversion (ECV) was performed. All patients received amiodarone (200 mg daily) for 3 months and then were randomized to amiodarone (Group I) or placebo (Group II) and followed for 15 months. The control group comprised 9 untreated patients undergoing ECV. Treatment effectiveness was evaluated using a Bayesian model. Results: Eighteen months after AF reversion, 22 (81.5%) patients in Group I, 13 (54.2%) patients in Group II, and 1 (11.1%) patient in the control group remained in sinus rhythm. No differences were found between Group I patients who required ECV and Group II patients. Sinus rhythm was preserved in all Group I patients when it was achieved during amiodarone administration. Limiting adverse effects occurred in 3 (11.1%) patients in Group I. Conclusions: In patients regaining sinus rhythm after the first episode of persistent AF, a 3-month amiodarone treatment after reversion is a reasonable option for rhythm control.

    Automated Axial Right Ventricle to Left Ventricle Diameter Ratio Computation in Computed Tomography Pulmonary Angiography

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    Background and Purpose Right Ventricular to Left Ventricular (RV/LV) diameter ratio has been shown to be a prognostic biomarker for patients suffering from acute Pulmonary Embolism (PE). While Computed Tomography Pulmonary Angiography (CTPA) images used to confirm a clinical suspicion of PE do include information of the heart, a numerical RV/LV diameter ratio is not universally reported, likely because of lack in training, inter-reader variability in the measurements, and additional effort by the radiologist. This study designs and validates a completely automated Computer Aided Detection (CAD) system to compute the axial RV/LV diameter ratio from CTPA images so that the RV/LV diameter ratio can be a more objective metric that is consistently reported in patients for whom CTPA diagnoses PE. Materials and Methods The CAD system was designed specifically for RV/LV measurements. The system was tested in 198 consecutive CTPA patients with acute PE. Its accuracy was evaluated using reference standard RV/LV radiologist measurements and its prognostic value was established for 30-day PE-specific mortality and a composite outcome of 30-day PE-specific mortality or the need for intensive therapies. The study was Institutional Review Board (IRB) approved and HIPAA compliant. Results The CAD system analyzed correctly 92.4% (183/198) of CTPA studies. The mean difference between automated and manually computed axial RV/LV ratios was 0.03±0.22. The correlation between the RV/LV diameter ratio obtained by the CAD system and that obtained by the radiologist was high (r=0.81). Compared to the radiologist, the CAD system equally achieved high accuracy for the composite outcome, with areas under the receiver operating characteristic curves of 0.75 vs. 0.78. Similar results were found for 30-days PE-specific mortality, with areas under the curve of 0.72 vs. 0.75. Conclusions An automated CAD system for determining the CT derived RV/LV diameter ratio in patients with acute PE has high accuracy when compared to manual measurements and similar prognostic significance for two clinical outcomes.Madrid-MIT M+Vision Consortiu

    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

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    Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

    Full factorial design applied to the synthesis of Pd-?Ag nanobars by the polyol method and the perspective for ethanol oxidation

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    Full factorial design methodology was applied to the synthesis and optimization of Pd–Ag nanobars usingthe polyol process as the reducer. The concentration of Br? ions, the temperature and the reaction timewere selected as factors to study, whereas the yield (% nanobars) was the response to be analyzed. Thenanoparticles were characterized by X-ray diffraction, energy-dispersive X-ray spectroscopy,transmission electron microscopy, high-resolution transmission electron microscopy and X-rayphotoelectron spectroscopy. The nanoparticles were also tested for the ethanol electro-oxidationreaction by cyclic voltammetry in alkaline solution. The three factors had a positive effect onthe response: the nanobar yield increased as the level of the variables changed from ?1 to +1. Thetemperature and reaction time were the most determinant variables (main and interacting) on thenanobar yield, whereas the concentration of Br? influenced the yield to a lesser extent. After designingthree optimum experiments, a maximum nanobar yield of 47.3% was obtained. The more negativeelectro-oxidation onset, higher current density and more negative current peak potential show that theincorporation of Ag into Pd nanobars improves the kinetic and thermodynamic behavior towards theethanol electro-oxidation reaction compared with that obtained with nanometrically pure Pd nanobars.This improvement is the result of surface modification caused by the incorporation of Ag in theformation of Pd–Ag bimetallic nanobars with (200) surfaces

    Aislamiento y control microbiológico de leuconostoc mesenteroides, en un ingenio para optimizar el rendimiento de azucar y etanol.

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    La caña de azúcar (Saccharum officinarum L) es exprimida para obtenersu jugo que después de ser purificado y neutralizado, deja cristalizar elazúcar Considerando la importancia que representa la caña de azúcarpara la industria azucarera, se hace necesario incrementar el contenido desacarosa libre de dextrana (destrucción de sacarosa causada por la acciónde microorganismos acompañantes de la caña, siendo uno de los másimportantes Leuconostoc mesenteroides). En este trabajo de investigaciónse determinó la inhibición de la bacteria ácido-láctica L. mesenteroidesaislada en un ingenio azucarero del Valle del Cauca mediante la utilizaciónde microorganismos antagonistas. Para esto, se realizaron aislamientos ycultivos de L. mesenteroides provenientes deljugo de la caña y se realizaronlas diferentes pruebas bioquímicas y microbiológicas en el laboratorio parael aislamiento y la identificación de las cepas tanto de Leuconostoc me¬senteroides, como las cepas bacterianas antagonistas a ella. Se comprobóque las cepas de los hongos Metharhizium anisopliae y Trichoderma sp,fueron las mas eficientes en el control de crecimiento de L. mesenteroi¬des; mostrando significativamente un mayor porcentaje de inhibición encomparación de los hongos filamentosos Colletotrichum sp, Thichodermaviridae, Rhizoctonia sp; y las bacterias Bacillus subtilis y Serratia marcensesy las levaduras Rhodothorula Rubra y KIoeckera japónica, no presentaroninhibición del crecimiento de Lmesenteroides. Además, se identificó a loshongos Aspergillus sp, Botrytis sp y Streptomyces sp como antagonistasnaturales y habituales presentes en el jugo de caña de los Ingenios

    Controlled drop emission by wetting properties in driven liquid filaments

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    The controlled formation of micrometre-sized drops is of great importance to many technological applications1, 2, 3, 4, 5. Here we present a wetting-based destabilization mechanism of forced microfilaments on either hydrophilic or hydrophobic stripes that leads to the periodic emission of droplets. The drop emission mechanism is triggered above the maximum critical forcing at which wetting, capillarity, viscous friction and gravity can balance to sustain a stable driven contact line. The corresponding critical filament velocity is predicted as a function of the static wetting angle, which can be tuned through the substrate behaviour, and shows a strong dependence on the filament size. This sensitivity explains the qualitative difference in the critical velocity between hydrophilic and hydrophobic stripes, and accounts for previous experimental results of splashing solids6. We demonstrate that this mechanism can be used to control independently the drop size and emission period, opening the possibility of highly monodisperse and flexible drop production techniques in open microfluidic geometries
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