Las migraciones bolivianas en la encrucijada interdisciplinar : evolución, cambios y tendencias

Esta obra reúne los trabajos de un conjunto de investigadoras e investigadores que, desde diversas disciplinas (sociología, geografía, historia, demografía) y aproximaciones metodológicas, han abordado el estudio de las migraciones bolivianas y sus impactos. A partir de estudios de caso llevados a cabo en diferentes contextos, los autores de esta obra cubren un amplio espectro de zonas geográficas y permiten avanzar hacia una comprensión transnacional de las dinámicas migratorias, desde un campo de observación que asume que las personas migrantes están inmersas en espacios sociales transnacionales, multi-locales, que afectan tanto a quienes emigran como a los que permanecen en las zonas de origen

Crustal thickness and velocity structure across the Moroccan Atlas from long offset wide-angle reflection seismic data: The SIMA experiment

The crustal structure and topography of the Moho boundary beneath the Atlas Mountains of Morocco has been constrained by a controlled source, wide-angle seismic reflection transect: the SIMA experiment. This paper presents the first results of this project, consisting of an almost 700 km long, high-resolution seismic profile acquired from the Sahara craton across the High and the Middle Atlas and the Rif Mountains. The interpretation of this seismic data set is based on forward modeling by raytracing, and has resulted in a detailed crustal structure and velocity model for the Atlas Mountains. Results indicate that the High Atlas features a moderate crustal thickness, with the Moho located at a minimum depth of 35 km to the S and at around 31 km to the N, in the Middle Atlas. Upper crustal shortening is resolved at depth through a crustal root where the Saharan crust underthrusts the northern Moroccan crust. This feature defines a lower crust imbrication that, locally, places the Moho boundary at 40-41 km depth in the northern part of the High Atlas. The P-wave velocity model is characterized by relatively low velocities, mostly in the lower crust and upper mantle, when compared to other active orogens and continental regions. These low deep crustal velocities together with other geophysical observables such as conductivity estimates derived from MT measurements, moderate Bouguer gravity anomaly, high heat flow, and surface exposures of recent alkaline volcanism lead to a model where partial melts are currently emplaced at deep crustal levels and in the upper mantle. The resulting model supports the existence of a mantle upwelling as mechanism that would contribute significantly to sustain the High Atlas topography. However, the detailed Moho geometry deduced in this work should lead to a revision of the exact geometry and position of this mantle feature and will require new modeling effortsThis work has been primarily funded by the Spanish MEC project CGL2007–63889. Additional funding was provided by projects CGL2010–15416, CSD2006-00041, and GL2009–09727 (Spain), CGL2008–03474-E, 07-TOPO_EUROPE_FP-006 (ESF Eurocores) and EAR-0808939 (US, NSF).Peer reviewe

Inhibición de Crecimiento Bacteriano en Agar de 2 Cepas Bacterianas por un Producto para la Higiene Íntima Femenina de pH Ácido y otro de pH Básico Comparados con Agua Destilada

Se realizó un estudio de la inhibición de crecimiento in vitro de cepas de Staphylococcus epidermidis y Staphylococcus aureus frente a 2 formulaciones indicadas para la higiene íntima femenina; una de pH ácido (pH 3,83) y otra de pH ligeramente básico (pH 8,0) por el método de difusión con discos. Se utilizó como comparador el agua destilada (pH 7,0). Los resultados demostraron que la exposición in vitro de los microorganismos S. aureus y S. epidermidis al producto de pH ácido resultó en inhibición de su crecimiento. La formulación de pH ligeramente alcalino, asociado a extracto de bardana (antiséptico), en ambas placas sembradas, resultó con halo de inhibición difuso y presentó colonias bacterianas en su interior. El disco con pH 7,0 no presentó halo de inhibición.Abstract BACTERIAL GROWTH INHIBITION TESTED WITH AGAR DISK-DIFFUSION METHOD OF TWO BACTERIAL STRAINS BY TWO PRODUCTS FOR FEMALE GENITAL HYGIENE, ONE OF ACID pH AND ANOTHER ONE WITH SLIGHTLY BASIC pH, COMPARED AGAINST DISTILLED WATER This study was based on the qualitative evaluation of bacterial growth inhibition of S. aureus and S. epidermidis by two different products for female genital hygiene, one with acidic pH (pH 3,83) and another one with slightly basic pH (pH 8,0) compared against distilled water (pH 7,0) by the disk-diffusion method on agar. The results showed that in vitro exposure of the microorganisms S. aureus and S. epidermidis to the acidic pH resulted in growth inhibition. The slightly alkaline product, associated with the antiseptic burdock extract, resulted in a diffuse inhibition zone with some bacterial colonies within. The disc with pH 7,0 distilled water showed no inhibition zone in any of the two tested bacterial strains

Total Nitrogen and Phosphorus From Tributary Rivers to the Lake of Maracaibo System, Venezuela

Nitrogen and phosphorus are primary nutrients, common constituents of fertilizers, detergents, and domestic and industrial wastewater discharges. These unloadings to rivers and subsequently to Lake Maracaibo cause nutrient and mineral enrichment, producing a secondary eutrophication on rivers and detained waters at deltas. Lake Maracaibo system is a basin of extraordinary importance because of its energetic resources, biodiversity and the wide number of aquatic organisms, which represents an important economic source for the country. However, activities being developed on the basin such as agricultural, cattle raising, mining and industrials, have modified the physical, chemical and biological characteristics of both water and soil generating an accelerated eutrophication process, as well as, the appearance of dense populations of the aquatic weed Lemna obscura, generating social, environmental and economic impacts. The following river basins were evaluated: Limón, Palmar, Santa Ana, Catatumbo, Escalante, Chama, Motatán, Misoa, Machango and Pueblo Viejo. These rivers contribute with 80% of the freshwater to the Lake Maracaibo system, being the Catatumbo river contribution 60% of the volume. Total nitrogen and total phosphorus average of rivers that drain to the Lake, was 1.20 and 0.84 mgl-1, respectively, contributing significantly with the process of eutrophication, that combined with the expansion of the agricultural borders, have caused deforestation, erosion and contamination, altering landscape and water availability, as well as an important increase of nutrients in Lake Maracaibo

Dynamic Structural Transformation of Resveratrol-Modified Stearate Liposomes Led to a Spontaneous Drug Release System

[[abstract]]A mono-substituted resveratrol derivative, resveratrol-modified stearate (RMS), was synthesized by selectively coupling of stearic acid to the monohroxyphenyl of resveratrol in order to enhance both the stability and bioavailability of resveratrol. The RMS self-assembles into liposomes and a series of suprastructural transformations into metastable helical ribbon, linear wire-like structures, and inert spherical nanoparticles were detected that may be induced by the hydrogen-bonding interactions. As a model for drug-release investigations, gold nanoparticles (AuNPs) were encapsulated successfully by RMS to generate vesicles and succeed to release AuNPs druing the transformation to a ribbon-like metastable stucture at ambient temperature.[[incitationindex]]SCI[[booktype]]電子