We are indebted to Profs. Victor Fernandez-Viagas and Weibo Liu for generously sharing their code and for guiding us on the reimplementation of their tiebreakers. We are very grateful to the referees, for their valuable comments on earlier versions of this paper. This research has been partially supported by the Fondo Nacional de Desarrollo Cient?fico, Tecnol?gico y de Innovaci?n Tecnol?gica (FONDECYT) and the World Bank through projects Kusisqa (014/2019 - FONDECYT - BM - INC.INV) and Het-FSSP (445/2019 - FONDECYT - PIB); and by the supercomputing center ?Inkari? of the Universidad Nacional de San Agust?n de Arequipa.

The current socio-economic situation creates similar conditions and rules for companies in various industries around the world.in this vein, the study and educate the retention factors of the company are of a great importance.  The task of staff productivity increase and the overall effectiveness of its activities is relevant. The most important role in addressing the issue of employee productivity and performance increasing, as well as his retention is played by employee engagement. The researchers studying engagement at work recognize that this phenomenon is multifaceted and define it as an employee's physical, cognitive and emotional state, causing excessive performance of his functional duties. Involvement is interconnected with the motivational potential of work, therefore, the conditions for the engagement development are the following ones: work significance and diversity, the co...

The objective of the present studywas to evaluate the Somatic Cell Count (SCC) in milk in dairy herds of theArequipa region.Milk samples were collected every twoweeks throughout the year 2005 from 15 dairy farms located in the irrigated area ofMajes, Santa Rita, and La Joya districts. Milk farms were stratified according to their technological level as high, medium, and low. The average SCCin the studywas 505 x 103 ± 150 x 103 cel/ ml, and for high, medium and lowtechnological level were 353, 559 y 603 x 103 cel/ml, respectively. Significant differences were found between levels of technology (p<0.05). The study showed an increase in SCC as the level of technology in the herd decreased.

The current socio-economic situation creates similar conditions and rules for companies in various industries around the world.in this vein, the study and educate the retention factors of the company are of a great importance.  The task of staff productivity increase and the overall effectiveness of its activities is relevant. The most important role in addressing the issue of employee productivity and performance increasing, as well as his retention is played by employee engagement. The researchers studying engagement at work recognize that this phenomenon is multifaceted and define it as an employee's physical, cognitive and emotional state, causing excessive performance of his functional duties. Involvement is interconnected with the motivational potential of work, therefore, the conditions for the engagement development are the following ones: work significance and diversity, the co...

El presente estudio tuvo como objetivo evaluar el recuento de células somáticas (RCS) en establos lecheros de la zona deArequipa. Se recolectaron muestras quincenales de leche en el 2005 de 15 establos lecheros de las irrigaciones deMajes, Santa Rita y La Joya. Los establos se estratificaron de acuerdo a su nivel tecnológico en alta, media y baja. El promediogeneral de células somáticas fue de 505 x 103 ± 150 x 103 cel/ml, y para los niveles tecnológicos de alta,media y baja fueron de 353, 559 y 603 x 103 cel/ml, respectivamente, habiendo diferencias significativas entre niveles tecnológicos (p<0.05). El estudio demuestra un incremento en el número de células somáticas en la leche a medida que disminuye el nivel tecnológico de los establos.

En una primera parte se sitúa la zona estudiada en el medio físico. Posteriormente, en el capítulo de la hidrogeología, se incluye: un resumen de las informaciones obtenidas, concretadas en diferentes cuadros y gráficos. La exposición y comentario de las principales características deducidas del análisis de dichas informaciones. Recomendaciones prácticas a fin de facilitar el desarrollo de la etapa final. La presentación de todo este contenido se ha facilitado con una clasificación arbitraria, por zonas que comprenden grupos de pozos y propiedades agrícolas.

The objective of the present study was to evaluate the frequency of ?-lactams and tetracyclines in raw milk samples contaminated with antibiotics in the dairy area of Arequipa. A total of 616 milk samples were collected in October 2007, and 99 of them were contaminated with antibiotics. Among them, the frequency of samples containing ? - lactams and tetracyclines was 88.8 and 61.6% respectively. The number of samples contaminated with b-lactams was statistically higher as compared to those contaminated with tetracyclines (p<0.01). The study showed that antibiotics belonging to the ?-lactams group are an important source of contamination of milk in the dairy area of Arequipa.

The objective of the present study was to evaluate the frequency of ?-lactams and tetracyclines in raw milk samples contaminated with antibiotics in the dairy area of Arequipa. A total of 616 milk samples were collected in October 2007, and 99 of them were contaminated with antibiotics. Among them, the frequency of samples containing ? - lactams and tetracyclines was 88.8 and 61.6% respectively. The number of samples contaminated with b-lactams was statistically higher as compared to those contaminated with tetracyclines (p<0.01). The study showed that antibiotics belonging to the ?-lactams group are an important source of contamination of milk in the dairy area of Arequipa.

Realiza un estudio de las posibilidades de explotación de las aguas del subsuelo del barrio de la Merced (distrito de Comas, provincia de Lima).

5 páginas.

3 páginas.

This study is a geochemical investigation of the Andean and Foreland basins of the Amazon River at high spatial and time resolution, carried out within the framework of the HYBAM research program (Hydro-geodynamics of the Amazon Basin). Monthly sampling was carried out at 27 gauging stations located in the upper tributaries of the Amazon Basin (from north to south: the Napo, Marañon, Ucayali, Madre de Dios-Beni and Mamore Rivers). The aim of this paper is to estimate the present-day chemical weathering rate (CWR), as well as the flux of CO2 consumption from total and silicate weathering in the Andes and Foreland Amazon basins, and to discuss their distribution as a function of geomorphic and structural parameters. Based on the forward method, the Napo and other Ecuadorian basins present high silicate weathering rates in comparison with the other basins. We confirm that the Marañon and ...