37 research outputs found
Impact of coffee crop renewal program on small producers in department cundinamarca (colombia)
The modernization of crops through renewal is a vital option for the restoration of the productivity and competitiveness of the coffee crop. The Federación Nacional de Cafeteros (National Federation of Coffee) is banking on a strategy that promotes renewal by providing resources to stimulate growers. As a result of the implementation of the program, it is hoped that it will reverse the aging process of coffee crops, consolidate a productive and competitive market, provide appropriate ages and densities and promote the use of coffee rust resistant varieties. Similarly, it is expected that small producers, who constitute the majority of farmers and who presumably suffer major limitations to independent renewal, will be the main beneficiaries
Regulatory T Cells in the Pathogenesis and Healing of Chronic Human Dermal Leishmaniasis Caused by Leishmania (Viannia) Species
The immune inflammatory response is a double edged sword. During infectious diseases, regulatory T cells can prevent eradication of the pathogen but can also limit inflammation and tissue damage. We investigated the role of regulatory T cells in chronic dermal leishmaniasis caused by species of the parasite Leishmania that are endemic in South and Central America. We found that although individuals with chronic lesions have increased regulatory T cells in their blood and at skin sites where immune responses to Leishmania were taking place compared to infected individuals who do not develop disease, their capacity to control the inflammatory response to Leishmania was inferior. However, healing of chronic lesions at the end of treatment was accompanied by an increase in the number and capacity of regulatory T cells to inhibit the function of effector T cells that mediate the inflammatory response. Different subsets of regulatory T cells, defined by the expression of molecular markers, were identified during chronic disease and healing, supporting the participation of distinct regulatory T cells in the development of disease and the control of inflammation during the healing response. Immunotherapeutic strategies may allow these regulatory T cell subsets to be mobilized or mitigated to achieve healing
Structure and non-structure of centrosomal proteins
Here we perform a large-scale study of the structural properties and the expression of proteins that constitute the human Centrosome. Centrosomal proteins tend to be larger than generic human proteins (control set), since their genes contain in average more exons (20.3 versus 14.6). They are rich in predicted disordered regions, which cover 57% of their length, compared to 39% in the general human proteome. They also contain several regions that are dually predicted to be disordered and coiled-coil at the same time: 55 proteins (15%) contain disordered and coiled-coil fragments that cover more than 20% of their length. Helices prevail over strands in regions homologous to known structures (47% predicted helical residues against 17% predicted as strands), and even more in the whole centrosomal proteome (52% against 7%), while for control human proteins 34.5% of the residues are predicted as helical and 12.8% are predicted as strands. This difference is mainly due to residues predicted as disordered and helical (30% in centrosomal and 9.4% in control proteins), which may correspond to alpha-helix forming molecular recognition features (α-MoRFs). We performed expression assays for 120 full-length centrosomal proteins and 72 domain constructs that we have predicted to be globular. These full-length proteins are often insoluble: Only 39 out of 120 expressed proteins (32%) and 19 out of 72 domains (26%) were soluble. We built or retrieved structural models for 277 out of 361 human proteins whose centrosomal localization has been experimentally verified. We could not find any suitable structural template with more than 20% sequence identity for 84 centrosomal proteins (23%), for which around 74% of the residues are predicted to be disordered or coiled-coils. The three-dimensional models that we built are available at http://ub.cbm.uam.es/centrosome/models/index.php
Evaluación del programa de salud ocupacional de Una empresa transformadora de papel en la Ciudad de Cali, planta 1
La calidad y nivel de vida de los hombres en una sociedad están claramente
determinados por las posibilidades que cada individuo tiene y aprovecha para
satisfacer sus necesidades es así como el trabajo es la principal actividad diaria
que realizan el hombre y la mujer y a través de éste, la humanidad ha logrado su
desarrollo, sin embargo, el tipo y las condiciones de trabajo influyen
significativamente en la salud, privilegiándola o deteriorándola.
La salud y el trabajo son hechos históricos; tienen realidades sociales concretas
que se encuentran en estado de permanente cambio. Las formas de organización
y las condiciones de trabajo varían históricamente y con ellas las circunstancias
que agreden o favorecen la salud de los trabajadores. En este sentido resulta
evidente que las condiciones de trabajo y las agresiones a la salud que enfrenta
un trabajador en la antigüedad, son muy distintas a las que enfrenta uno de esta
época. Así mismo, el tipo de enfermedad difiere entre los trabajadores
históricamente; un ejemplo es que la alta incidencia de enfermedades infecciosas
que sufrían los trabajadores en épocas pasadas, ha cedido su lugar a la neurosis
ocupacional y a otros trastornos mentales de la sociedad capitalista moderna, fruto
en gran parte de tareas sumamente repetitivas, monótonas o de los extenuantes y
rotativos turnos1.Justificación2.Objetivos3.Información general de la empresa4.Marco teórico5. Metodologia de la investigación6.Estructura7.Evaluación de la estructura8.Resultados de la estructuraPregradoProfesional en Seguridad y Salud en el Trabaj
A General-Purpose Element-Based Approach to Compute Dispersion Relations in Periodic Materials with Existing Finite Element Codes
The numerical determination of dispersion relations in periodic materials via the finite element method is a difficult task in most standard codes. Here, we propose a novel technique which allows the computation of these band structures from local elemental subroutines in contrast with existing methods which impose Bloch boundary conditions on the global arrays. The proposed local approach is thus readily applicable to several physical contexts and space dimensionalities. Here we present the details of this element-based algorithm and provide verification results for three different kinematic assumptions applied to phononic crystals in a classical and a micropolar elastic medium. The paper also includes in the form of supplementary material, a fully-coded user subroutine and a test-problem to be used in a commercial finite element code. © 2019 IMACS
The Cali meteorite fall: A new H/L ordinary chondrite
10 pages, 6 figures, 5 tablesThe fall of the Cali meteorite took place on 6 July 2007 at 16 h 32 ± 1 min local time (21 h 32 ± 1 min UTC). A daylight fireball was witnessed by hundreds of people in the Cauca Valley in Colombia from which 10 meteorite samples with a total mass of 478 g were recovered near 3°24.3'N, 76°30.6'W. The fireball trajectory and radiant have been reconstructed with moderate accuracy. From the computed radiant and from considering various plausible velocities, we obtained a range of orbital solutions that suggest that the Cali progenitor meteoroid probably originated in the main asteroid belt. Based on petrography, mineral chemistry, magnetic susceptibility, fhermoluminescence, and bulk chemistry, the Cali meteorite is classified as an H/L4 ordinary chondrite brecciaThis work was partially supported by NASA Cosmochemistry grants NNH05AB65I to JNG and NNG06GF95G to AER and NASA Discovery Data Analysis grant NNX08G17G to DWGS. JMTR also thanks CSIC for a JAE-Doc research contractPeer Reviewe