85 research outputs found
Variable control tool in MATLAB for energy transformation processes
During the stages of transformation of energy in a process, exercise control over the variables that intervene in it, improve its performance, and identify undesirable conditions in these. Thus, this study is developed as a graphical interface to implement a methodology for controlling variables of energy conversion processes, such as internal combustion engines. The control tool developed in MATLAB variables is based on multivariate statistics. The methods for developing this tool of Graphic User Interface is based on the statistics of principal component analysis and failure statistics such as T! Hotelling and the Q statistic that allows the control of anomalies presented in the operation's behavior. About the methodology, first, the input data are normalized, achieving standardization of the observation matrix vs. variables, then the spectral decomposition of the normalized data is performed, reaching the generation of the matrix of auto-values, allowing the age of the projection space of the data. With this based and delimited, it is possible to establish the ranges of observation of the mentioned statisticians. The result obtained from this research corresponds to software that allows the constant observation and analysis of the behavior of each variable of the generation engine. It describes the upper limit, lower limit, arithmetic mean, principal components, graphics of the statistics, and detects the failures in real times
Fuzzy logic methodology to study the behavior of energy transformation processes based on statistics t2 and q
In the processes of energy transformation, to carry out an adequate follow-up of the process parameters represent an opportunity to propose strategies to improve the processes' performance. For this reason, it is essential to analyze the behavior of process variables under the quantitative and qualitative optics supported by the experts. Thus, this work proposes a methodology of fuzzy Mandani type logic that allows the analysis of energy transformation processes (such as internal combustion engines) based on T2 and Q statistics, as a way to identify whether the operation limits are kept within the normal or exceed the limits, achieving to identify the anomaly in the process. In the initial stage, MATLAB implements two diffuse systems; the first system aims to determine the impact variables have on the generation of an anomaly, without identifying the type of defect. In the second stage, it's defined as a function of the number guests, the kind of monster that occurs in the observations made from the transition range in the operation of the system analyzed, until the last measurement obtained. In the third stage, the statistics T2, Q, and its limits are determined from the operating variables of the selected system. Finally, the previously calculated statistics are graphically processed in the diffuse systems. The results obtained in this work show that the analysis of processes or phenomena based on qualitative observations, the methodology implemented, is a useful tool for decision making in the industrial sector
Geographical variability of bacterial communities of cryoconite holes of Andean glaciers
Cryoconite holes, ponds full of melting water with sediment on the bottom, are hotspots of biodiversity on glacier surfaces and host dynamic micro-ecosystems. They have been extensively investigated in different areas of the world (e.g., the Arctic, Antarctic, Alps, and Himalaya), but so far no study has described the bacterial communities of the glaciers in the Andes, the world’s longest mountain range. In this study, we describe the bacterial communities of three small (< 2 km2) high-elevation (< 4200 m a.s.l.) glaciers of the Central Andes (Iver, East Iver and Morado glaciers) and two large (> 85 km2) glaciers of the Patagonian Andes (Exploradores and Perito Moreno glaciers) whose ablation tongues reach low altitude (< 300 m a.s.l.). Results show that the bacterial communities were generally similar to those observed in the cryoconite holes of other continents, but with few cyanobacteria (0.5% of sequences). The most abundant orders were Betaproteobacteriales, Cytophagales, Chitinophagales, Acetobacterales, Frankiales, Armatimonadales, Sphingobacteriales, Rhizobiales, Bacteroidales, Sphingomonadales, and Micrococcales. The bacterial communities differed between glaciers and both water pH and O2 concentration appeared to influence the bacterial community composition. This work thus provides the first description of the bacterial communities in cryoconite holes of South American glaciers
Estado Ecológico de la Laguna de Usphaq’ocha, Santuario Nacional de Ampay, Abancay – Apurímac
Se evaluó el estado ecológico de la laguna de Usphaq’ocha, ubicada en el Santuario Nacional del Ampay, durante el periodo de noviembre de 2017 a febrero de 2018. La profundidad máxima registrada fue de 7.5 m. Se identificaron 6 géneros de fitoplancton pertenecientes a 4 divisiones, mientras que los macrófitos fueron representados por 34 especies circundantes, con las familias más abundantes siendo Asteraceae, Brassicaceae, Berberidaceae, Lamiaceae, Melastomataceae, Rosaceae y Urticaceae. En cuanto a la fauna, se identificaron 7 familias de macroinvertebrados de 3 clases, así como 8 especies de aves terrestres y acuáticas. Durante el periodo de estudio, no se observaron peces, anfibios, reptiles ni mamíferos silvestres asociados a la laguna. La evaluación física y química del cuerpo de agua reveló una temperatura promedio de 14 °C, un pH de 8, una concentración de oxígeno disuelto de 7.4 mg/L, una conductividad eléctrica de 170 µS/cm, y niveles de fósforo total de 0.2 mg/L y nitrógeno total de 0.1 mg/L. No se detectó la presencia de coliformes fecales, evidenciando la ausencia de descargas contaminantes al agua (<1000 NMP/100 ml). Según la valoración de los indicadores morfológicos, el estado fue clasificado como “bueno”; los indicadores biológicos como “malo”; y los indicadores físicos, químicos y bacteriológicos como “bueno/muy bueno”. El estado ecológico de la laguna Usphaq’ocha es de “bueno”
Rapid NO conversion with an enhanced Sm+3-TiO2 photocatalyst
Nitrogen oxides (NOx) are known for having a significant greenhouse effect and provoking several health issues. Because of that, it is necessary to find an effective manner to remove them from polluted air. In this study, samarium-doped titania was synthesized via sol-gel using two different synthesis routes and varying the calcination temperature and the Sm3+ content. The main difference between the two syntheses was the pH solution. The acidic pH favored the presence of the anatase crystalline phase, the most photoactive and interesting for photocatalytic applications. Furthermore, these catalysts were evaluated in a lab-scale UV photoreactor following the NO conversion via chemiluminescence, according to the ISO standard 22197–1. The Sm content positively affected the NO removal. The highest NO conversion was 92 %, with the doped titania obtained at a calcination temperature of 500 ◦C and with 0.5 % wt. of samarium. This result was congruent with the reported literature’s energy bandgap estimated (2.98 eV)
Consenso peruano para el uso de la resonancia magnética en el diagnóstico y seguimiento de pacientes con esclerosis múltiple
The use of Magnetic Resonance Imaging (MRI) in the diagnosis and follow-up of patients with Multiple Sclerosis (MS) has optimized the care of the affected patients. Several international working groups have tried to clarify and standardize the global use of MRI but, on many occasions, data are extrapolated from other regions, do not contemplate local realities or are difficult to implement. Objective: To reach a consensus on aspects related to the use of MRI in the diagnosis and follow-up of patients with MS in Peru. Material and Methods: A group of Peruvian experts (neurologists and radiologists) worked on the elaboration of the consensus using a remote survey round methodology. Results: The recommendations, established on the basis of published evidence and on the experts’ criteria, focused on the role of both, the conventional MRI techniques and the measurement of brain atrophy in MS patients both at the time of diagnosis and during the follow-up period. Conclusions: The consensual recommendations could potentially assist in the standardization and optimization of the care and follow-up of patients with MS in our country.El uso de la resonancia magnética (RM) en el diagnóstico y seguimiento de pacientes con esclerosis múltiple (EM) ha optimizado el cuidado de los pacientes afectados. Diversos grupos internacionales de trabajo han intentado clarificar y normatizar el uso global de la RM pero, en muchas ocasiones, se extrapolan datos de otras regiones que no contemplan la realidad de cada lugar o son difíciles de implementar. Objetivo: Consensuar aspectos relacionados con el uso de RM en el diagnóstico y seguimiento de pacientes con EM en el Perú. Material y Métodos: Un grupo de expertos peruanos, conformado por neurólogos y radiólogos, condujo la elaboración del consenso mediante metodología de ronda de encuestas a la distancia. Resultados: Las recomendaciones, basadas en la evidencia publicada y en el criterio de los expertos, enfocaron tanto el rol de las técnicas convencionales de RM como el de la medición de la atrofia cerebral en pacientes con EM al momento del diagnóstico y durante el periodo de seguimiento. Conclusiones: Las recomendaciones del consenso podrán potencialmente homogenizar y optimizar el cuidado y seguimiento de pacientes con EM en nuestro país
Global, regional, and national age-sex specific all-cause and cause-specific mortality for 240 causes of death, 1990-2013: A systematic analysis for the Global Burden of Disease Study 2013
Background Up-to-date evidence on levels and trends for age-sex-specific all-cause and cause-specific mortality is essential for the formation of global, regional, and national health policies. In the Global Burden of Disease Study 2013 (GBD 2013) we estimated yearly deaths for 188 countries between 1990, and 2013. We used the results to assess whether there is epidemiological convergence across countries. Methods We estimated age-sex-specific all-cause mortality using the GBD 2010 methods with some refinements to improve accuracy applied to an updated database of vital registration, survey, and census data. We generally estimated cause of death as in the GBD 2010. Key improvements included the addition of more recent vital registration data for 72 countries, an updated verbal autopsy literature review, two new and detailed data systems for China, and more detail for Mexico, UK, Turkey, and Russia. We improved statistical models for garbage code redistribution. We used six different modelling strategies across the 240 causes; cause of death ensemble modelling (CODEm) was the dominant strategy for causes with sufficient information. Trends for Alzheimer's disease and other dementias were informed by meta-regression of prevalence studies. For pathogen-specific causes of diarrhoea and lower respiratory infections we used a counterfactual approach. We computed two measures of convergence (inequality) across countries: the average relative difference across all pairs of countries (Gini coefficient) and the average absolute difference across countries. To summarise broad findings, we used multiple decrement life-tables to decompose probabilities of death from birth to exact age 15 years, from exact age 15 years to exact age 50 years, and from exact age 50 years to exact age 75 years, and life expectancy at birth into major causes. For all quantities reported, we computed 95% uncertainty intervals (UIs). We constrained cause-specific fractions within each age-sex-country-year group to sum to all-cause mortality based on draws from the uncertainty distributions. Findings Global life expectancy for both sexes increased from 65·3 years (UI 65·0-65·6) in 1990, to 71·5 years (UI 71·0-71·9) in 2013, while the number of deaths increased from 47·5 million (UI 46·8-48·2) to 54·9 million (UI 53·6-56·3) over the same interval. Global progress masked variation by age and sex: for children, average absolute differences between countries decreased but relative differences increased. For women aged 25-39 years and older than 75 years and for men aged 20-49 years and 65 years and older, both absolute and relative differences increased. Decomposition of global and regional life expectancy showed the prominent role of reductions in age-standardised death rates for cardiovascular diseases and cancers in high-income regions, and reductions in child deaths from diarrhoea, lower respiratory infections, and neonatal causes in low-income regions. HIV/AIDS reduced life expectancy in southern sub-Saharan Africa. For most communicable causes of death both numbers of deaths and age-standardised death rates fell whereas for most non-communicable causes, demographic shifts have increased numbers of deaths but decreased age-standardised death rates. Global deaths from injury increased by 10·7%, from 4·3 million deaths in 1990 to 4·8 million in 2013; but age-standardised rates declined over the same period by 21%. For some causes of more than 100 000 deaths per year in 2013, age-standardised death rates increased between 1990 and 2013, including HIV/AIDS, pancreatic cancer, atrial fibrillation and flutter, drug use disorders, diabetes, chronic kidney disease, and sickle-cell anaemias. Diarrhoeal diseases, lower respiratory infections, neonatal causes, and malaria are still in the top five causes of death in children younger than 5 years. The most important pathogens are rotavirus for diarrhoea and pneumococcus for lower respiratory infections. Country-specific probabilities of death over three phases of life were substantially varied between and within regions. Interpretation For most countries, the general pattern of reductions in age-sex specific mortality has been associated with a progressive shift towards a larger share of the remaining deaths caused by non-communicable disease and injuries. Assessing epidemiological convergence across countries depends on whether an absolute or relative measure of inequality is used. Nevertheless, age-standardised death rates for seven substantial causes are increasing, suggesting the potential for reversals in some countries. Important gaps exist in the empirical data for cause of death estimates for some countries; for example, no national data for India are available for the past decade. Funding Bill & Melinda Gates Foundation
A difference between sexes: temporal variation in the diet of Carollia perspicillata (Chiroptera, Phyllostomidae) at the Macaregua cave, Santander (Colombia)
Organisms adjust their foraging strategies to optimize the energetic costs during foraging with respect to benefits gained. These strategies are usually different in males and females due to their specific requirements during reproduction. Knowing the temporal dietary composition and variation may help us understand how intrinsic factors can influence diet during the breeding season. Seba’s short–tailed fruit bat (Carollia perspicillata) plays an important role in seed dispersal throughout the Neotropics. Seasonal dietary changes related to resource availability have been documented but dietary differences between males and females have not been analyzed. We tested the hypothesis that dietary breadth increases and varies between males and females of Carollia perspicillata during the breeding season. We collected 295 fecal samples (from 236 males and 182 females) between June 2012 and April 2013 at the Macaregua cave (Santander, Colombia). Sex, diet and overlap were recorded. Time series analysis of dietary variation were estimated and related to food (fruits and flowers) availability. Males were found to include 18 seed morphospecies within their diet, while females included 16 seed morphospecies. Ficus, Vismia and Acacia were the most commonly consumed plant genera within the diet of both males and females. The time series analysis throughout the year indicated that males had greater dietary diversity than females. Dietary richness for males peaked multiple times, while dietary richness for females peaked only once during the transition period between pregnancy and lactation. We recorded significant sex differences in the value of importance of plants in the diet, evenness, and dominance of plant species consumed, as well as differential consumption over the seasons. Knowing the variations in the diet allows us to address the differences between the foraging strategies that females and males use in response to energy demands, movement patterns and habitat use. This is essential to understand all those processes that organisms must carry out for their survival and maintenance.</jats:p
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Fidelity of Implementation (FOI) of the Grade 10 English Curriculum: Developing a FOI Framework for Curriculum Delivery
Fidelity of implementation (FOI) is employed to probe into the implementation of the curriculum by English teachers as intended by developers through the curriculum guide. This explanatory-sequential paper sought to probe into the fidelity of implementation practice of high school English teachers using the dimensions of adherence, duration and quality of delivery. Data were gathered using the Curriculum Fidelity of Implementation Survey-Questionnaire, focus group discussion and document analysis. Data analyses were conducted using quantitative and qualitative approaches. Findings revealed that teachers mostly implement the curriculum with average adherence but cited several reasons for not accomplishing the learning competencies. Overall, high quality of delivery was observed and the required time allotment for the Grade 10 English subject was implemented; however, these did not translate to the full implementation of the curriculum. Reasons such as lack of orientation on the learning competencies, intervening and other-teaching related activities, professional development programs during class days, among others resort to teachers’ backlogged discussion of the competencies. Implications of and recommendation for the study were provided for future researchers and empirical discussion
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