AC Response to Humidity and Propane of Sprayed Fe-Zn Oxide Films

Iron-zinc oxide films with different Zn contents were ultrasonically sprayed on glass substrates and inter-digital gold electrodes were evaporated upon them. Films were deposited from solutions containing 2, 10 and 30 at. % Zn. Hematite, amorphous and Franklinite structures turned out, respectively. They were assessed as humidity and propane detectors under alternating-current conditions for frequencies from 1 to 105 Hz and temperatures 30 and 250 oC. Their impedances in dry air, humid air and humid air plus propane were determined from voltage measurements with a Lock-In amplifier. Sensitivities to humidity (53 % RH.) and 189, 500 and 786 ppm of propane from the response of the resistance, reactance and also the total impedance were determined as functions of frequency. The maximum sensitivity to humidity ranges from 24 % up to 308 %. For propane, the maximum sensitivity ranges from 45 % up to 711 %. The largest sensitivity values correspond in all cases to reactance. From the dynamical response, the response and recovery times are determined, along with the concentration-dependence of the sensitivity. The sensing mechanisms are commented

The perception of construction professionals on sustainable building issues in México and Chile

El crecimiento poblacional se encuentra directamente ligado a la edificación; por tal motivo, resulta fundamental ser eficientes con los recursos, pues todo en un marco de desarrollo sustentable y su adopción dentro de los procesos constructivos es un tema de investigación importante. Mientras que investigaciones basadas en encuestas postocupación (POE) son una forma común de abordar el tema, poco se conoce de la forma como los actores de la construcción perciben e incorporan las prácticas de uso eficiente de los recursos para con sus actividades. En el presente trabajo se muestran los resultados de una encuesta pre-ocupación (EPO) diseñada a partir de las certificaciones LEED y BREEAM, la norma mexicana NMX-AA-164-SCFI-2013, el Programa de Construcción de Edificaciones Sustentables (PCES), la Certificación de Edificaciones Sustentables (CES) y la Certificación de Estándares de Construcción Sustentable en Chile (ECSC). La encuesta estuvo dirigida a profesionales de la construcción en México y Chile, y a raíz de ella se encontró que hay bajo conocimiento y poco empleo de tácticas de edificación sustentable entre la población objeto de estudio; cabe concluir que las técnicas que utilizan están orientadas a la optimización de costo.Population growth is directly linked to construction, for this reason it is essential to be efficient with resources, all within a framework of sustainable development, and its adoption within construction processes is an important research topic. While research based on Post-Occupancy Surveys (POE) is a common way to address the issue, little is known about the way in which construction stakeholders perceive and incorporate efficient resource use practices into their activities. This paper shows the results of a Pre-Occupancy Survey (EPO) designed based on the LEED and BREEAM certifications, the Mexican standard NMX-AA-164-SCFI-2013, the Sustainable Building Construction Program (PCES), the Certification of Sustainable Buildings (CES) and Sustainable Construction Standards in Chile (ECSC). The survey was aimed at construction professionals in Mexico and Chile, finding that there is low knowledge and use of sustainable building tactics and it is concluded that the techniques they use are oriented to cost optimization

Empagliflozin in Patients with Chronic Kidney Disease

Background The effects of empagliflozin in patients with chronic kidney disease who are at risk for disease progression are not well understood. The EMPA-KIDNEY trial was designed to assess the effects of treatment with empagliflozin in a broad range of such patients. Methods We enrolled patients with chronic kidney disease who had an estimated glomerular filtration rate (eGFR) of at least 20 but less than 45 ml per minute per 1.73 m(2) of body-surface area, or who had an eGFR of at least 45 but less than 90 ml per minute per 1.73 m(2) with a urinary albumin-to-creatinine ratio (with albumin measured in milligrams and creatinine measured in grams) of at least 200. Patients were randomly assigned to receive empagliflozin (10 mg once daily) or matching placebo. The primary outcome was a composite of progression of kidney disease (defined as end-stage kidney disease, a sustained decrease in eGFR to < 10 ml per minute per 1.73 m(2), a sustained decrease in eGFR of & GE;40% from baseline, or death from renal causes) or death from cardiovascular causes. Results A total of 6609 patients underwent randomization. During a median of 2.0 years of follow-up, progression of kidney disease or death from cardiovascular causes occurred in 432 of 3304 patients (13.1%) in the empagliflozin group and in 558 of 3305 patients (16.9%) in the placebo group (hazard ratio, 0.72; 95% confidence interval [CI], 0.64 to 0.82; P < 0.001). Results were consistent among patients with or without diabetes and across subgroups defined according to eGFR ranges. The rate of hospitalization from any cause was lower in the empagliflozin group than in the placebo group (hazard ratio, 0.86; 95% CI, 0.78 to 0.95; P=0.003), but there were no significant between-group differences with respect to the composite outcome of hospitalization for heart failure or death from cardiovascular causes (which occurred in 4.0% in the empagliflozin group and 4.6% in the placebo group) or death from any cause (in 4.5% and 5.1%, respectively). The rates of serious adverse events were similar in the two groups. Conclusions Among a wide range of patients with chronic kidney disease who were at risk for disease progression, empagliflozin therapy led to a lower risk of progression of kidney disease or death from cardiovascular causes than placebo