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Se estudiaron las oscilaciones locales de las velocidades Doppler en la penumbra de la mancha solarAR12186. Para ello, se alinearon las imágenes usando el método Enhanced Correlation Coefficient (ECC),ECC+Rotación y el método propuesto por Griñón-Marín et al. (2020). Se utilizó la transformada de waveletpara extraer las potencias wavelet. Analizando la distribución de los períodos de oscilación de las potenciasde wavelet de forma local y global, no se identificó un periodo dominante en dichas potencias. También, seobtuvo una atenuación en las potencias Doppler del 22,1% y 41,6% respecto a las potencias obtenidas através del método ECC+Rotación para las potencias encontradas usando el método ECC y el método deGriñón-Marín et al. (2020). Además, no se encontró una correlación entre las potencias correspondientes alas velocidades Doppler y magnitud del campo magnético en la línea de la visión para los tres métodos dealineación.

Resumen Introducción y objetivos: El trauma cardiaco en países subdesarrollados es de predominio penetrante, con altas tasas de mortalidad extrahospitalaria, pero con mortalidad intrahospitalaria que dependerá en parte de si el paciente se encuentra taponado o no. Las técnicas mínimamente invasivas para practicar la ventana pericárdica y la nueva interpretación del resultado positivo, han hecho variar paradigmas previamente establecido, lo cual ha llevado a realizar un cambio en el abordaje inicial de los pacientes con trauma precordial penetrante estables hemodinámicamente. Por lo cual, queremos mostrar nuestra experiencia en el manejo mínimamente invasivo de pacientes estables hemodinámicamente llevados a ventana pericárdica por trauma precordial. Materiales: En un periodo entre el 2018 y el 2019, se evaluaron 5 pacientes con herida penetrante precordial al servicio de trauma Hospital Universitario del Valle Evaristo García lo cuales fueron manejados por cirugía mínimamente invasiva. Resultados: Pacientes con e-FAST(tomado de las siglas en inglés, Extended Focused Assessment with Sonography in Trauma) positivo subxifoideo; llevados a ventana pericárdica por toracoscopia y laparoscopia, todas positivas con identificación de lesiones en pericardio, aurícula derecha , ventrículo izquierdo y auricula izquierda no sangrante, manejadas con lavado con SSN 500 cc hasta obtener líquido claro, aspiración de coágulos. Drenaje de hemotórax y Toracostomía cerrada para abordaje torácico. 72 horas retiro de tubo de tórax y egresó sin complicaciones documentadas. Conclusiones: La cirugía mínimamente invasiva en trauma resulta ser efectiva y segura para el manejo del trauma penetrante precordial en el paciente estable hemodinámicamente. Evitando toracotomías y esternotomías innecesarias.

Este artículo presenta los resultados de una investigación acerca de los costos de producción de la miel de abeja, su rentabilidad y el impacto que produce la explotación en la Provincia del Guayas, donde existen 49 apicultores según el último censo realizado por el MAG en el 2018; la metodología y herramientas que se utilizó para realizar la investigación se obtuvo mediante información estadística y encuestas que permitieron el estudio de mercado aplicadas a productores donde se encontró como resultado que los tres segmentos apícolas no cuentan con las herramientas necesarias para optimizar el proceso productivo además de la falta de educación financiera, y sobre la utilidad se pudo concluir que mientras más grande es el segmento, mayor es su rentabilidad.

En Honduras, los estudios sobre murciélagos son escasos y se desconoce cómo la actividad de los murciélagos filostómidos es influenciada por factores ambientales. Describimos patrones de actividad de especies de murciélagos filostómidos en Ciudad Universitaria, Francisco Morazán (centro de Honduras). Realizamos 21 jornadas y capturamos murciélagos con 2 redes de niebla del 26 de febrero de 2015 al 29 de abril de 2016. En total, se registraron 114 individuos en 1,428.24 horas/red/metro. Con base en el análisis ANOVA, los murciélagos filostómidos se encontraron entre 58 % y 93.5 % de humedad relativa del aire, y entre 17.4 ºC y 22.8 ºC de temperatura del aire. Nuestros resultados indican diferencias interespecíficas en la actividad de los murciélagos filostómidos en el área de estudio. Este es el primer intento en describir sus patrones de actividad en un bosque seco en Honduras.

Soil leachates from di(2-ethylhexyl)phthalate-contaminated soil to groundwater could potentially cause toxicity, depending on the physical and chemical properties of the soil, and modifications in the phthalate, thus affecting health in nearby human populations. For this reason, the following study was accomplished, evaluating the effectiveness of soil remediation based on the Toxicity Characteristic Leaching Procedure-like leachates from treated soil. Since there are not any environmental regulations for this emerging contaminant in country, simply reducing the DEHP concentration in soil or leachates was not sufficient for regulatory purposes to assure regulators of remediation success. As an alternative, acute toxicity was used as the cleanup criterion. This was done using the filter paper test of Organization for Economic Cooperation and Development Protocol No. 207 with earthworms, which was applicable, since the country in which the study was done is a member of the Organization for Economic Cooperation and Development, and accepts its test protocols. In contaminated soil leachates, the earthworms exhibited a ruptured body wall with bloody wounds and expulsion of coelomic fluid, and those surviving worms showed a reduction in movement with practically null response to stimulus. Contaminated soil treated by chemical oxidation with 2.5% of hydrogen peroxide showed the greatest toxicity reduction, up to 94%, demonstrating the technical feasibility of this treatment method. The soil treated by bioremediation (simulation of landfarm operation) was also effective after five months of treatment, showing no significant difference with the negative control (uncontaminated soil).

Se analizaron tres alternativas para la estabilización de taludes: estabilización con material reciclable (llantas), muros de contención y bermas; se consideraron factores económicos, sociales, culturales y constructivos, donde resultó que la construcción de bermas es la solución más factible, técnica y económica. Con suelos de tres diferentes características geotécnicas encontrados en el talud adyacente al hospital Luis Moscoso Zambrano del cantón Piñas, provincia de El Oro, el cual se ha declarado como zona vulnerable, se realizó el análisis estático de estabilidad de talud mediante la aplicación del programa Geo Slope. Se incluyó los métodos Ordinario de Fellenius, de Bishop, de Janbu, de Morgenstern y Price y de Spencer. La investigación bibliográfica de diversas fuentes como revistas, artículos, libros, sitios web, periódicos, entre otros, conllevo a un análisis cimentado. Por medio del análisis de forma directa se ejecutó 3 perforaciones a una profundidad de 1,40 metros y luego realizar los ensayos de comprensión simple, granulometría y límites de Atterberg; se procedió a la extracción de la topografía del terreno mediante Global Mapper para importarlo en Civil 3D, donde se trazó un alineamiento que permitió la obtención de 7 perfiles, con la finalidad de obtener los datos requeridos por Geo Slope. Se efectuó el diseño de la alternativa seleccionada fundamentado por la investigación bibliográfica, además se implementó un diseño de drenaje como protección a las bermas. Por último, se presenta el presupuesto determinado por el cálculo de volúmenes de obra y los planos.

El presente estudio se realizó con el objetivo de obtener información geotécnica de parte de la zona sur-este de la ciudad de Machala, y en base a tal información definir la alternativa técnica adecuada de cimentación para una edificación de tres plantas del tipo residencial. Para el procedimiento de exploración del suelo se implementó la Norma Ecuatoriana de la Construcción NEC respecto a “Geotecnia y cimentaciones”, en la cual define que para una edificación de tres plantas y según las cargas de servicio es necesario analizar el suelo a una profundidad de 6m (NEC – 2015). El estudio tuvo en general una cobertura 160 Ha de superficie, se realizó en cuatro sectores: Ciudadela “San Ramón”, terreno en Avenida Colón Tinoco y Alejandro Castro Benítez, Ciudadela “García Guillen” y Lotización “Francisco Abad Vallejo”, se realizó una perforación en cada sector mencionado, formando los cuatro puntos de exploración un polígono, esto pretendiendo estimar la secuencia de los estratos de los sectores y definir una carta estratigráfica georreferenciada que sirva para prever el tipo de suelo existente en determinado punto dentro del polígono analizado. La exploración se realizó con el equipo SPT, obteniendo muestras inalteradas durante la exploración y que fueron ensayadas en laboratorio. Los resultados del estudio de suelos presentaron que bajo estas zonas el terreno sería del tipo arcilloso, limoso, arenas finas, con rango de carga admisible entre 2 a 6 Ton/m2, nivel freático entre 1 a 2 m respecto al nivel del suelo natural. Por lo cual, fue necesario mejorar el suelo de soporte y para la cimentación se eligió definitivamente un sistema ortogonal de vigas de cimentación con zapatas de un metro.

Actualmente se han desarrollado diferentes estudios para lograr el aprovechamiento de agregados no convencionales en la preparación de mezclas de concreto, en este caso en particular se han analizado los efectos de la fibra natural de caña de azúcar como medrador de las características físicas y mecánicas en el hormigón. El presente trabajo experimental se inició con una previa investigación bibliográfica de la dosificación requerida para la elaboración de probetas de hormigón que cumplan con los requisitos establecidos en la normativa vigente en el país. Una vez estudiada dicha información se procedió con el procesamiento de la caña de azúcar, removiendo las fibras naturales de su tallo, posteriormente las fibras fueron cortadas y lavadas tanto en agua fría como caliente en reiteradas ocasiones para luego secarlas de forma natural durante una semana, asegurando así la total eliminación de los azucares e impurezas propias de la caña. Finalmente, se distribuyeron dentro de la mezcla de forma homogénea en un equivalente de 2.37 kg/m3 en función al peso del cemento. Analizando los resultados obtenidos se evidenciaron variaciones relativamente bajas en relación a las presentadas por el hormigón utilizado para las muestras de control, tanto en trabajabilidad, como consistencia. Sin embargo, los ensayos demostraron que las mejoras si fueron notables en la resistencia a la compresión, pues se demostró que las fibras naturales de la caña de azúcar mejoran la respuesta mecánica del hormigón.

Objective To assess the diagnostic performance of high-sensitivity troponin T (hs-TnT) in patients with suspected non-ST elevation acute coronary syndrome (NSTE-ACS); confirm whether it shortens the time to diagnosis; and analyze the clinical consequences derived from its use. Method A prospective, longitudinal observational study was carried out in 5 emergency care departments. Patients seen for chest pain with suspected of NSTE-ACS were consecutively included. Patient care followed the internal protocols of the center, based on the consensus guidelines of the European Society of Cardiology. Serial conventional cardiac troponin (cTn) and hs-TnT determinations were made. Results A total of 351 patients were included in the study. A final diagnosis of acute myocardial infarction (AMI) was established in 77 patients, with unstable angina in 102, and no acute coronary syndrome in 172 patients. The hs-TnT values were above percentile 99% in a large number of patients without AMI. In the initial determination, the diagnostic sensitivity of the hs-TnT was significantly greater than that of cTn (87.0% vs. 42.9%), which led to a negative predictive value of 95.1%. Conclusions High-sensitivity troponin T improves diagnostic performance compared with conventional troponin assay, shortens the time to diagnosis, and identifies a larger number of patients with smaller myocardial infarctions.

Measurement(s) spatial region Technology Type(s) occurrent Sample Characteristic - Organism Mammalia center dot Chiroptera sp. BOLD:AAA2524 Sample Characteristic - Environment cave system center dot karst cave Sample Characteristic - Location Global Understanding biodiversity patterns as well as drivers of population declines, and range losses provides crucial baselines for monitoring and conservation. However, the information needed to evaluate such trends remains unstandardised and sparsely available for many taxonomic groups and habitats, including the cave-dwelling bats and cave ecosystems. We developed the DarkCideS 1.0 (), a global database of bat caves and species synthesised from publicly available information and datasets. The DarkCideS 1.0 is by far the largest database for cave-dwelling bats, which contains information for geographical location, ecological status, species traits, and parasites and hyperparasites for 679 bat species are known to occur in caves or use caves in part of their life histories. The database currently contains 6746 georeferenced occurrences for 402 cave-dwelling bat species from 2002 cave sites in 46 countries and 12 terrestrial biomes. The database has been developed to be collaborative and open-access, allowing continuous data-sharing among the community of bat researchers and conservation biologists to advance bat research and comparative monitoring and prioritisation for conservation.

Resumen Los autores presentan un caso de hematoma subcapsular roto y del cuarto segmento del hígado en una mujer de 26 años, en la semana 36 del embarazo, complicada por preeclampsia. Los signos clínicos de preeclampsia se asociaron con dolor en el hipocondrio derecho y hallazgos de laboratorio compatibles con un verdadero síndrome HELLP. Se realizó una laparotomía de emergencia con rotura hepática y hemoperitoneo. Se realizó una cirugía de control de daños, con drenaje de hemoperitoneo, packing hepático y uso de una bolsa de Bogotá. El desempaque se realizó a las 24 horas y la colocación de la terapia de VAC asociada con la malla con el posterior cierre de la fascia dentro de los 10 días. Se presentan diferentes opciones terapéuticas que incluyen intervenciones médicas, quirúrgicas y radiológicas. No se puede definir una estrategia única. El enfoque multidisciplinario parece obligatorio. La cirugía debe permanecer lo menos agresiva posible.

Honduras health workers are reduced; doctors and nurses are getting infected by COVID-19. The primary purpose of this project is the design and development of software that performs facial recognition and temperature registration for patients. The incremental model was used to develop the software. The algorithm was trained with 5 images per face for the first test and 10 images per face for the second, with a total sample of 80 participants. At a maximum distance of 1.4 meters from the camera, the system obtained 72% and 82% accuracy for each of the tests. Finally, the authors conclude that the system can be implemented in health areas such as laboratories, hospitals, and clinics so that contact between patients and doctors can be reduced.

Background Agroforestry bridges the gap that often separates agriculture and forestry by building integrated systems that address both environmental and socio-economic objectives. Agroforestry can improve the resiliency of agricultural systems and mitigate the impacts of climate change. Existing research suggests that integrating trees on farms can prevent environmental degradation, improve agricultural productivity, increase carbon sequestration, generate cleaner water, and support healthy soil and healthy ecosystems while providing stable incomes and other benefits to human welfare. Although these claims are becoming more widely accepted as the body of agroforestry research increases, systematic understanding of the evidence supporting them remains lacking for high-income countries. This systematic map will address this research need by providing a tool for identifying and visualizing the existing evidence demonstrating the impacts of agroforestry practices and interventions on agricultural productivity, ecosystem services, and human well-being. The results will be useful for informing policy decisions and future research by making the evidence easily accessible and highlighting the gaps in knowledge as well as areas with enough evidence to conduct systematic reviews. Methods This systematic map will identify, collect, display, and describe available evidence on the impacts of agroforestry on agricultural productivity, ecosystem services, and human well-being in high-income countries. The search strategy will cover 5 primary databases and 24 organizational websites using a pre-defined search string designed to capture studies relating agroforestry practices and interventions to outcomes in high-income countries. The searches will all be conducted in English. We will screen the identified studies for inclusion or exclusion in stages, first on title and abstract and then on full-text. We will collect data from studies included at the full-text stage to form the map and associated database. For inclusion, the study in question must assess the impacts of the deliberate promotion and/or actual integration of woody perennials (trees, shrubs, palms, bamboos, etc.) on the same land management unit as agricultural crops and/or animals.

Las alteraciones morfológicas de la próstata, por las que se realiza cribado son la hiperplasiaprostática benigna (HPB) y el cáncer de próstata (CaP). La HPB es el tumor benigno más frecuenteen varones mayores de 50 años, se caracteriza por el aumento del volumen de la glándula y usualmente acompañado de síntomas urinarios. El CaP es la segunda causa de muerte relacionada con cáncer en Estados Unidos y Europa en mayores de 70 años, su incidencia por debajo de los 50 es rara. El cribado o pruebas de detección, tiene como meta el hallar el cáncer antes de la aparición de síntomas, el cribado no se realiza en pacientes por sospechar que tienen cáncer, sino como un método de pesquisa. El objetivo de este artículo, es efectuar una revisión a los referentes teóricos, y proponer un nuevo algoritmo diagnóstico de alteraciones morfológicas de la próstata, basado en la evidencia.

In the late years, the use of acellular dermal matrix (ADM) has extended rapidly in the field of breast reconstruction. However, with the follow-up visits, we discovered some deformities on the lateral part of the lower pole, due to the folding of the ADM. The aim of this letter is to share some tricks developed in our clinical practice that would permit the surgeon to avoid getting these irregularities in the aesthetic result of breast reconstruction with ADM. This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

During the construction of many roads, slope stability problems can occur, resulting in a delayed completion of the construction as well as an increased final budget. However, there is still limited data collected that reveals the actual costs of geotechnical issues. The Diezma landslide, affecting the A-92 highway (Granada, SE Spain), is a great example of this situation. The construction project, which was started in 1988, did not identify the geotechnical instabilities of this zone, thus no preventive measures were recommended. The landslide-induced disruption of the highway involved economic losses related to the implementation of corrective measures and to indirect costs. In this paper, an evaluation of direct and indirect costs induced by the landslide is developed, and as a result, the potential cost savings of an adequate geotechnical survey are obtained.

We have probed the pulsating variable star content of the isolated Local Group dwarf galaxy, DDO210 (Aquarius), using archival Advanced Camera for Surveys/$Hubble$ $Space$ $Telescope$ imaging in the F475W and F814W passbands. We find a total of 32 RR Lyrae stars (24 ab-type, 8 c-type) and 75 Cepheid variables. The mean periods of the ab-type and c-type RR Lyrae stars are calculated to be $\langle$P$_{\mathrm{ab}}\rangle = 0.609\pm0.011$ and $\langle$P$_{\mathrm{c}}\rangle = 0.359\pm0.025$ days, respectively. The light curve properties of the fundamental mode RR Lyrae stars yield a mean metallicity of $\langle$[Fe/H]$\rangle$ = -1.63$\pm$0.11 dex for this ancient population, consistent with a recent synthetic colour-magnitude diagram analysis. We find this galaxy to be Oosterhoff-intermediate and lacking in high-amplitude, short-period ab-type RR Lyrae, consistent with behavior recently observed for many dwarf spheroidals and ultra-faint dwarfs in the Local Group. We find a distance modulus of $\mu = 25.07\pm 0.12$ as determined by the RR Lyrae stars, slightly larger but agreeing with recent distance estimates from the red giant branch tip. We also find a sizable population of Cepheid variables in this galaxy. We provide evidence in favor of most if not all of these stars being short-period classical Cepheids. Assuming all of these stars to be classical Cepheids, we find that most of these Cepheids are $\sim$300 Myr old, with the youngest Cepheids being offset from the older Cepheids and the centre of the galaxy. We conclude that this may have resulted from a migration of star formation in DDO210., Comment: Accepted for publication into MNRAS, 17 pages, 13 figures, 4 tables

To assess the diagnostic performance of high-sensitivity troponin T (hs-TnT) in patients with suspected non-ST elevation acute coronary syndrome (NSTE-ACS); confirm whether it shortens the time to diagnosis; and analyze the clinical consequences derived from its use.A prospective, longitudinal observational study was carried out in 5 emergency care departments. Patients seen for chest pain with suspected of NSTE-ACS were consecutively included. Patient care followed the internal protocols of the center, based on the consensus guidelines of the European Society of Cardiology. Serial conventional cardiac troponin (cTn) and hs-TnT determinations were made.A total of 351 patients were included in the study. A final diagnosis of acute myocardial infarction (AMI) was established in 77 patients, with unstable angina in 102, and no acute coronary syndrome in 172 patients. The hs-TnT values were above percentile 99% in a large number of patients without AMI. In the initial determination, the diagnostic sensitivity of the hs-TnT was significantly greater than that of cTn (87.0% vs. 42.9%), which led to a negative predictive value of 95.1%.High-sensitivity troponin T improves diagnostic performance compared with conventional troponin assay, shortens the time to diagnosis, and identifies a larger number of patients with smaller myocardial infarctions.

En la actualidad se acepta que el daño oxidativo juega un papel esencial en la patogénesis del síndrome metabólico. Estudios recientes proponen al daño oxidativo como diana terapéutica frente al síndrome metabólico. Precisamente nuestro objetivo fue mejorar el estatus total antioxidante (TAS) de mujeres con síndrome metabólico mediante ejercicio aeróbico. Participaron voluntariamente 100 mujeres con síndrome metabólico de acuerdo con los criterios del National Cholesterol Educational Program (Adult-Treatment-Panel-III) distribuidas aleatoriamente en grupo experimental (n = 60) y control (n = 40). El grupo experimental desarrolló un programa de entrenamiento aeróbico sobre tapiz rodante de intensidad ligera/moderada de 12 semanas (5 sesiones/semana). La determinación del TAS plasmático se realizó mediante espectrofotometría utilizando kits comercializados por Randox Lab. Este protocolo fue aprobado por un Comité de Etica Institucional. Tras completar el programa de entrenamiento se incrementó significativamente el TAS (0.79 ± 0.05 vs.1.01 ± 0.03 mmol/l; p = 0.027). No hubo cambios en grupo control. El ejercicio aeróbico de intensidad ligera/moderada aumenta las defensas antioxidantes en mujeres con síndrome metabólico. Son necesarios futuros estudios longitudinales para conocer su impacto en la evolución clínica.A 12-week training protocol increased antioxidant defense system in young adult women with metabolic syndrome. It is generally accepted that oxidative stress is implicated in the pathogenesis of metabolic syndrome. Furthermore, recent studies have reported that stress may be acting as a therapeutic target in metabolic syndrome. Consequently, this study was designed to explore whether aerobic training may increase plasmatic total antioxidant status in women with metabolic syndrome. A total of 100 young adult women with metabolic syndrome according to the criteria reported by the National Cholesterol Education Program (Adult-Treatment-Panel-III) volunteered for this study. Of them, 60 were randomly included in the experimental group to enter a 12-week aerobic training program, 5 days/week, at low/moderate intensity. The control group included 40 age, sex and body mass index (BMI)-matched women with metabolic syndrome who did not enter any training program. Total antioxidant status (TAS) was assayed in plasma using colorimetric Randox kits. This protocol was approved by an Institutional Ethics Committee. When compared to baseline, plasmatic TAS was significantly increased (0.79 ± 0.05 Vs 1.01 ± 0.03 mmol/l; p = 0.027). No changes were found in controls. A 12-week aerobic training program increased plasmatic TAS in adult women with metabolic syndrome. Further long-term well-conducted studies are required in order to highlight the potential clinical benefits of TAS improvement.

Resumen Mas alla del papel en el transporte reverso de colesterol de las lipoproteinas de alta densidad (HDL), en la ultima decada se han descrito nuevos mecanismos antiaterogenicos de las HDL. Dos de estos mecanismos, estrechamente relacionados, son la capacidad de las HDL para prevenir la oxidacion de las lipoproteinas de baja densidad (LDL) y su actividad antiinflamatoria. Algunas propiedades antiinflamatorias de la HDL son mediadas por el contenido en algunos lipidos, como el colesterol no esterificado o la esfingosina-1- fosfato; sin embargo, la principal actividad antiinflamatoria de las HDL la ejercen las apolipoproteinas (apo) y enzimas asociadas. Proteinas como apo A-I, proteina transferidora de esteres de colesterol, paraoxonasa, acetilhidrolasa del factor activador plaquetario y apo J actuan coordinadamente para transferir los peroxidos lipidicos, potentes agentes oxidantes, desde las LDL oxidadas hasta las HDL, captarlos y degradarlos generando productos no inflamatorios. El contenido relativo de estas proteinas en las diferentes subfracciones de HDL determina el potencial antiinflamatorio de cada subfraccion.

We report a new analysis protocol for HCN hyperfine data, based on the PYSPECKIT package, and results of using this new protocol to analyse a sample area of seven massive molecular clumps from the Census of High- and Medium-mass Protostars (CHaMP) survey, in order to derive maps of column density for this species. There is a strong correlation between the HCN integrated intensity, IHCN, and previously reported IHCO+ in the clumps, but IN2H+ is not well correlated with either of these other two "dense gas tracers". The four fitted parameters from PYSPECKIT in this region fall in the range of VLSR = 8-10 km/s, {\sigma} V = 1.2-2.2 km/s, Tex = 4-15 K, and {\tau} = 0.2-2.5. These parameters allow us to derive a column density map of these clouds, without limiting assumptions about the excitation or opacity. A more traditional (linear) method of converting IHCN to total mass column gives much lower clump masses than our results based on the hyperfine analysis. This is primarily due to areas in the sample region of low I, low Tex, and high {\tau} . We conclude that there may be more dense gas in these massive clumps not engaged in massive star formation than previously recognized. If this result holds for other clouds in the CHaMP sample, it would have dramatic consequences for the calibration of the Kennicutt-Schmidt star formation laws, including a large increase in the gas depletion time-scale in such regions.

Accessibility to the Ecuadorian Amazonian region is critical due to its high level of isolation and lack of infrastructure, which restricts people’s mobility to long walks, river boats, small planes or a combination of them. Building roads in the Amazon region will expedite accessibility and socio-economic development; however it has a high environmental impact. Finding alternative solutions for transportation without endangering the Amazon ecosystem is a challenge for sustainability. Using the extensive network of rivers in the Amazon is becoming a potential solution for transportation. However, this mean of mobility faces its own drawbacks related to fuel cost and availability, environmental impacts and fuel smuggling through the border impacting national security. Electric canoes coupled with renewable energy systems represent an alternative that has been successfully applied in several parts of the world, including Galapagos-Ecuador. Therefore, this paper aims to present a technical-economic analysis of solar canoes to be used in rivers of the southern part of the Ecuadorian Amazonian where more than 500 indigenous families live. These communities now have electricity, through individual photovoltaic systems from the “Yatsa Ii Etsari” project developed by the local utility. The results show that solar canoes are a technical and economical option for autonomous navigation up to 4 hours, representing a sustainable alternative for river transportation in the Ecuadorian Amazon.

We have tested the reliability of the red giant branch (RGB) as a metallicity indicator accounting for observational errors as well as the complexity of star formation histories (SFHs) and chemical evolution histories observed in various stellar systems. We generate model color-magnitude diagrams (CMDs) produced with a variety of evolutionary histories and compare the resultant metallicity estimates from the colors and magnitudes of RGB stars to the true input metallicities. We include realistic models for photometric errors and completeness in our synthetic CMDs. As expected, for simple simple stellar populations dominated by old stars, the RGB provides a very accurate estimate of the modular metallicity value for a population. An error in the age of a system targeted for this type of study may produce metallicity errors of a few tenths of a dex. The size of this metallicity error depends linearly on the age error, and we find this dependence to be stronger with more precise photometry. If the population has experienced any significant star formation within the last $\sim$6 Gyr, the metallicity estimates, [M/H], derived from the RGB may be in error by up to $\sim$0.5 dex. Perhaps the most important consideration for this technique is an accurate, independent estimate of the average age for the target stellar system, especially if it is probable that a significant fraction of the population formed less than $\sim$6 Gyr ago., Accepted for publication in AJ

Nowadays, there are many types of holographic recording medium some of them are photopolymer systems that generally consist of a polymeric host matrix, photopolymerizable momomer, photosensitizing dye and charge transfer agent but some of them have an undesirable feature, the toxicity of their components. Therefore, the present research study material recording, vinyl acetate is selected as polymeric matrix and natural dye from “muicle plant” is used as the photoinitiation these components are not toxic. The films are fabricated using gravity settling method at room temperature by this method, uniform films is obtained with good optical quality. To characterize the medium, been obtained when the coherent reed light (632.8 nm) was sent normally to the grating.