1
artículo
Publicado 2017
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In this study, we investigate changes in the glaciated surface and the formation of lakes in the headwater of the Querococha watershed in Cordillera Blanca (Peru) using 24 Landsat images from 1975 to 2014. Information of glacier retreat was integrated with available climate data, the first survey of recent depositional dynamics in proglacial Yanamarey Lake (4600m a.s.l.), and a relatively short hydrological record (2002-2014) at the outlet of Yanamarey Lake. A statistically significant temperature warming (0.21°C decade-1 for mean annual temperature) has been detected in the region, and it caused a reduction of the glacierized area since 1975 from 3.5 to 1.4km-2. New small lakes formed in the deglaciated areas, increasing the flooded area from1.8ha in 1976 to 2.8ha in 2014. A positive correlation between annual rates of glacier recession and runoff was found. Sediment cores revealed a h...
2
artículo
Publicado 2015
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This work analysed the changes in air temperature in 25 meteorological stations in the Altiplano and the surrounding Andean slopes of Bolivia and Peru, and their relationship with El Niño-Southern Oscillation (SO) and the Pacific Decadal Oscillation (PDO). The analysis focused on annual, warm season (DJF) and cold season (JJA) maximum and minimum temperatures. All analyses were undertaken during 1965-2012, but some analyses were also from 1945 and 1955 when data were available. Principal component analysis was applied to the annual and seasonal series to identify spatial differences of changes in maximum and minimum air temperature. There was an overall increase of temperatures since the mid-20th century. The most intense and spatially coherent warming was observed for annual and warm season maximum temperature, with warming rates from 0.15 to 0.25 °C decade-1. Changes in the cold seas...
3
tesis de grado
Publicado 2019
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OBJETIVO: Determinar las complicaciones maternas y perinatales en primigestas del tercer trimestre con infección del tracto urinario atendidas en el Hospital Regional Hermilio Valdizán Medrano. Huánuco, 2018. METODOLOGÍA: Estudio descriptivo, básica no experimental, de corte transversal y retrospectivo, cuya población fue de 440 gestantes con diagnóstico de infección del tracto urinario atendidas en el Hospital Regional Hermilio Valdizán Medrano. Huánuco, 2018. Mediante un muestreo no probabilístico por conveniencia, con criterios de inclusión y exclusión se obtuvo una muestra de 158 primigestas del tercer trimestre con infección del tracto urinario. RESULTADOS: Las características sociodemográficas de las gestantes con infección del tracto urinario fueron, la mayoría tuvieron las edades entre 11 a 19 años (54.4%), estado civil conviviente (63.9%), grado de instrucció...
4
artículo
La aplicación de las técnicas de la biología molecular y el éxito del Proyecto Genoma Humano ha abierto una nueva era tanto en Medicina como en Nutrición. Hasta la fecha, al menos, 1.000 genes humanos causantes de en fermedades han sido identificados y parcialmente carac terizados, el 97% de los cuales sabemos ahora que son causantes de enfermedades monogénicas. Sin embargo, otras patologías como la obesidad, enfermedad cardio vascular, diabetes, cáncer se deben a complejas interac ciones entre diversos genes y factores ambientales. A pe sar de los numerosos estudios de asociación, más de 600 publicados desde 2002, la base molecular de las enferme dades crónicas es todavía incierta. La información sobre polimorfismos de nucleótidos y mapas de haplotipos son recursos adicionales para identificar genes involucrados en enfermedades.
5
artículo
Publicado 2022
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In this research, the influence of the stiffness irregularity and the p-delta effect on the structural behavior of a reinforced concrete building is analyzed. The main objective is to determine the impact of the stiffness irregularity and the p-delta effect on the structural behavior in regular and irregular buildings. First, the linear dynamic analysis procedure is performed in order to determine the structural response in terms of drifts, shear force and moments per floor. Subsequently, we proceed with the nonlinear static analysis procedure to obtain the capacity curve of the structure. The post elastic stiffness and the overall ductility of the structure are determined from the capacity curve. Finally, a comparative analysis of the responses from the linear and nonlinear analysis is carried out to determine the percentage variation of the results. When analyzing the structures that c...
6
artículo
Publicado 2022
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A systematic review of the diagnostic methods described in the literature for the identification and characterization of species of the genus Salmonella was carried out. The review was carried out using publications from 2015 to 2021 registered in the NCBI/PubMed, ScienceDirect, Scopus, SciELO, Google Scholar and Springer databases and applying the PRISMA methodology. In total, 61 articles were analysed, grouping the data according to country of origin, type of sample, technique, microbiology protocol and genes used in molecular tests. The microbiology protocols are based on performing pre-enrichment in peptone water and enrichment in tetrathionate (TT) and Rappaport-Vassiliadis (RV) broths, especially with faecal or environmental samples, to subsequently carry out isolations in selective and differential media. The identification of some Salmonella sp serovars that cause disease in poul...
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This study assessed changes in the maximum and minimum surface air temperatures across Peru during the period 1964–2014. For this purpose, we employed the most complete records of air temperature series that were also subjected to a rigorous quality control and homogenization protocol. Based on the homogenized series, we created a monthly gridded data set of maximum and minimum air temperatures at a 5 × 5 km grid spacing. The results suggest a general warming trend in surface air temperature across Peru, albeit with clear spatial and seasonal variation. Our results also reveal some differences in the detectable trends between maximum and minimum air temperatures. Maximum air temperature trends mainly increased during the austral summer (DJF), but cold season minimum air temperature trends showed an opposite pattern, with the strongest warming being recorded in the austral winter (JJA)...
8
artículo
Publicado 2016
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This study detects climate trends and variability from precipitation and temperature observations in Ecuador and assesses their links to the El Niño Southern Oscillation (ENSO) for the period 1966–2011, using the El Niño 1+2 and El Niño 3.4 indices. Excluding the Amazonian region (for which there is a lack of data), two main regions were distinguishable in terms of variability and trends among climate variables, especially for precipitation. In general, there was no trend in precipitation for the coastal region, and a very close relationship between the magnitude and seasonal distribution of precipitation and the El Niño 1+2 variability was found. In contrast, for the mountainous region (the Andes), there was an increase of precipitation during the study period, and a signal of El Niño 3.4 influence was detected. Temperatures were spatially homogeneous and showed an intense warmin...
9
artículo
Seasonal and annual extreme precipitation over the Peruvian Andes have been mapped for the first time. Maps were developed using the most complete, quality-controlled and homogenous daily precipitation records in Peru from 1973 to 2016. For each observed rain gauge series, we defined parameters as the de-clustered daily intensity, total precipitation duration, total magnitude and dry-spell length. Then, we fitted the seasonal and annual series of these variables to a Generalized-Pareto distribution using a peak-over-threshold approach. We estimated the distribution parameters and validated the performance of different thresholds to obtain the best estimation of precipitation probability. We also mapped the distribution parameters obtained for the different meteorological stations using the universal kriging algorithm, accounting for elevation and the distance to the Pacific Ocean as co-v...