The study aimed to determine the frequency of neoplasmas that were histopathologically diagnosed at the Pathology Laboratory of School of Veterinary Medicine, San Marcos University in the period 1996-2007. The retrospective study included 73 cases of neoplasms. Animals older than 9 years of age (49.3%) and females (72.9%) were the most affected. Tumors of epithelial origin were the most common type (53.5%), being mammary adenocarcinoma (21.1%) and lymphoma (16.9%) the most frequent.

El presente estudio tuvo como objetivo determinar la frecuencia de neoplasias diagnosticadas histopatológicamente en el Laboratorio de Patología Veterinaria de la Facultad de Medicina Veterinaria de la Universidad Nacional Mayor de San Marcos entre los años 1996-2007. Se hizo un estudio retrospectivo empleándose 73 registros de neoplasias. Los animales mayores de 9 años (49.3%) y las hembras (72.9%) fueron los más afectados. Asimismo, las neoplasias de origen epitelial fueron las más frecuentes (53.5%), siendo el adenocarcinoma mamario (21.1%) y el linfoma (16.9%) los de mayor presentación.

The characteristics of the precipitation under the influence of topography and surface wind flow are investigated over South America. Here the precipitating cloud systems (PCSs) are identified using the Global Precipitation Measurement Precipitation Radar (GPM-PR) data, which provides the three dimensional radar reflectivity factor (Ze), rain rate, drop size and droplet concentration. For each PCSs the surface wind properties are estimated using European Center for Medium-Range Weather Forecast Interim data. Based on the direction of surface flow the PCSs are classified into five categories. Over the South America the near surface wind flow transports the moisture from Amazon basin to east flank of Andes and validated here. The directional surface flow decides the occurrences of the PCSs, as upslope consists of the higher and larger PCSs at the peak of Andes compared to downslope flow. T...

A sensitivity study of the performance of the Weather Research and Forecasting regional model (WRF, version 3.7) to the use of different microphysics, cumulus, and boundary layer parameterizations for short- and medium-term precipitation forecast is conducted in the Central Andes of Peru. Lin-Purdué, Thompson, and Morrison microphysics schemes were tested, as well as the Grell–Freitas, Grell 3d, and Betts–Miller–Janjic cumulus parameterizations.

Objetivos. Es un estudio prospectivo multiinstitucional que conlleva, a su vez, tres subestudios y luego se hace el metaanálisis de estos estudios piloto en pacientes con cáncer de mama localmente avanzado que reciben quimioterapia preoperatoria con antraciclinas en densidad de dosis seguido de tres esquemas diferentes, teniendo como objetivo llegar a la respuesta patológica completa (pCR). Material y métodos. Participaron 150 pacientes, 28 pacientes en el primer grupo (4AC+4AT), 57 pacientes en el segundo grupo (4AC+4CptT) y 65 pacientes en el tercer grupo (4AC+12TXe), todos de inicio cánceres inoperables no metastásicos. Resultados. En el primer grupo la RPC fue de 28%, en el segundo grupo 20% y en el tercer grupo 24%, que se incrementó a 35%, 19% y 30%, respectivamente, cuando solo se tabuló los datos de las pacientes que culminaron todo el tratamiento y que no presentaron pro...

Objetivos. Es un estudio prospectivo multiinstitucional que conlleva, a su vez, tres subestudios y luego se hace el metaanálisis de estos estudios piloto en pacientes con cáncer de mama localmente avanzado que reciben quimioterapia preoperatoria con antraciclinas en densidad de dosis seguido de tres esquemas diferentes, teniendo como objetivo llegar a la respuesta patológica completa (pCR). Material y métodos. Participaron 150 pacientes, 28 pacientes en el primer grupo (4AC+4AT), 57 pacientes en el segundo grupo (4AC+4CptT) y 65 pacientes en el tercer grupo (4AC+12TXe), todos de inicio cánceres inoperables no metastásicos. Resultados. En el primer grupo la RPC fue de 28%, en el segundo grupo 20% y en el tercer grupo 24%, que se incrementó a 35%, 19% y 30%, respectivamente, cuando solo se tabuló los datos de las pacientes que culminaron todo el tratamiento y que no presentaron pro...

In the Central Andes of Peru, convective and stratiform rainfall occurs, frequently associated with convective storms. The raindrop size distributions (RSD), measured by a Parsivel-2 optical disdrometer, were characterized by the variation of their normalized parameters. The RSD dataset includes measurements corresponding to 18 months between 2017 and 2019. As a result, it was found that the mass-weighted mean diameter Dm and the Nw parameter present respectively high and low values, in the interval of 15-20 LST (local standard time), wherein deeper and more active clouds appear. The events including convective rainfall contribute 67.5% of the accumulated total, wherein 92% corresponds to the 15-20 LST interval. It is concluded that the spectral variability of the RSD is strongly controlled by the cloudiness configuration field developing over the west (convection over highlands) and eas...

The ability of the WRF-ARW (Weather Research and Forecasting-Advanced Research WRF) model to forecast extreme rainfall in the Central Andes of Peru is evaluated in this study, using observations from stations located in the Mantaro basin and GOES (Geostationary Operational Environmental Satellite) images. The evaluation analyzes the synoptic conditions averaged over 40 extreme event cases, and considers model simulations organized in 4 nested domains. We first establish that atypical events in the region are those with more than 27 mm of rainfall per day when averaging over all the stations. More than 50% of the selected cases occurred during January, February, and April, with the most extreme occurring during February. The average synoptic conditions show negative geopotential anomalies and positive humidity anomalies in 700 and 500 hPa. At 200 hPa, the subtropical upper ridge or “Bol...

The ability of the WRF-ARW (Weather Research and Forecasting-Advanced Research WRF) model to forecast extreme rainfall in the Central Andes of Peru is evaluated, using observations from stations located in the Mantaro basin and GOES (Geostationary Operational Environmental Satellite) images. The evaluation analyzes the synoptic conditions averaged over 40 extreme event cases, and considers model simulations organized in 4 nested domains. Simulation results show that the Weather Research and Forecasting (WRF) model underestimates rainfall totals in approximately 50–60% of cases. The analysis of two case studies shows that the underestimation by the model is probably due to three reasons: inability to generate convection in the upstream Amazon during early morning hours, limitations on describing mesoscale processes that lead to vertical movements capable of producing extreme rainfall, a...

The work carried out a characterization of tropospheric vertical profiles in rainy and dry seasons by behavior of thermodynamic indices obtained with the WRF model for the period January 2018–March 2019 on the central Andes of Peru and its relationship with rainfall in the region. A case study was also analyzed using sounding observation data. The precipitation observed were taken from 8 meteorological stations located in the Mantaro basin belonging to the National Meteorological Service of Peru. As a results, it was found that the behavior of the thermodynamic parameters responds to the general characteristics of each period. The level of condensation was always higher in the dry period, in which the lower troposphere was also more stable. The KI, TT, Sweat and CAPE indices were always higher in the rainy season, as was water vapor mixing ratio. The vertical shear was mostly higher in...

The life cycle of clouds consists of mainly into three phases, namely developing, mature, and dissipating phases. The information about the vertical structure of the precipitation during different phases of development will improve their representation in the cloud models. Whether specific regimes over Peru favor the formation or decay of the cloud systems and how their intensity varies during different phases of development will provide the insight into the precipitation structure over Peru. We used two satellite-based data, namely from Global Precipitation Measurement dual Precipitation Radar (GPM-DPR) and GOES (Geostationary Operational Environmental Satellite) to expose the vertical structure of precipitation during different phases of the precipitating cloud systems (PCSs). A PCS is defined using the GPM based near surface rainfall data and then GOES-based brightness temperature (BT...

El presente proyecto de investigación propone crear, desarrollar y comercializar un producto innovador llamado EcoDínamo, que parte sobre la base de las ya existentes baterías externas que se ofrecen en el mercado peruano e internacional, agregando como elemento diferenciador al dínamo; que a través del uso de una manivela en el dispositivo, permite abastecer y transformar la energía mecánica a energía eléctrica. Así mismo, favorece la cultura ambiental.

El presente proyecto de investigación propone crear, desarrollar y comercializar un producto innovador llamado EcoDínamo, que parte sobre la base de las ya existentes baterías externas que se ofrecen en el mercado peruano e internacional, agregando como elemento diferenciador al dínamo; que a través del uso de una manivela en el dispositivo, permite abastecer y transformar la energía mecánica a energía eléctrica. Así mismo, favorece la cultura ambiental.

The present study comes under the project “MAGNET-IGP: Strengthening the research line in physics and microphysics of the atmosphere (Agreement No 010-2017-FONDECYT)”. Yamina Silva-Vidal, Jose Luis Flores-Rojas and Jairo Valdivia-Prado would like to acknowledge the Peruvian PPR068 programme "Reducción de vulnerabilidad y atención de emergencias por desastres" for financial support of their work. This work was done using computational resources, HPC-Linux -Cluster, from Laboratorio de Dinámica de Fluidos Geofísicos Computacionales at Instituto Geofísico del Perú (Grants 101-2014-FONDECYT, SPIRALES2012, IRD-IGP, Manglares IGP-IDRC, PP068 program).

Information on the vertical structure of rain, especially near the surface is important for accurate quantitative precipitation estimation from weather and space-borne radars. In the present study, the rainfall characteristics, from a vertically pointed profile Radar in the Mantaro basin (Huancayo, Peru) are observed. In summary, diurnal variation of near-surface rainfall and bright band height, average vertical profiles of the drop size distribution (DSD), rain rate, radar reflectivity (Ze) and liquid water content (LWC) are investigated to derive the rainfall characteristics. Diurnal variation of rain rate and bright band height show the bimodal distribution, where frequent and higher rain rate occurred during the afternoon and nighttime, and more than 70% bright band height found between 4.3-4.7 km. The average vertical profiles of Ze show the opposite characteristics above and below ...

A set of instruments to measure several physical, microphysical, and radiative properties of the atmosphere and clouds are essential to identify, understand and, subsequently, forecast and prevent the effects of extreme meteorological events, such as severe rainfall, hailstorms, frost events and high pollution events, that can occur with some regularity in the central Andes of Peru. However, like many other Latin American countries, Peru lacks an adequate network of meteorological stations to identify and analyze extreme meteorological events. To partially remedy this deficiency, the Geophysical Institute of Peru has installed a set of specialized sensors (LAMAR) on the Huancayo observatory (12.04◦ S, 75.32◦ W, 3350 m ASL), located in the Mantaro river basin, which is a part of the central Andes of Peru, especially in agricultural areas. LAMAR consists of a set of sensors that are us...