Una mirada antropológica sobre el conflicto, la desigualdad y los procesos de reinserción social en Colombia

For more than half of a century, Colombia has been living in a state of violence, a nationwide political violence. As the time goes by, this situation gets even worse. Now the violence is implanted for different interests, such as personal, political, social and economical interests. For this reason, the information for this thesis was gathered from the time of the independence, through the era of violence until today; considering a reflection that begins with the perspective of Marx, passing by a theoretical compilation of the conflict, with an anthropological, psychological, biological and sociological perspective. In addition, different theories about violence have been studied to recognize the ideological approach of the different armed movements that have emerged in Colombia. Statistical, economical and social data including class struggle, social stratification, exclusion and gender perspective among others, have been considered from an anthropological and interdisciplinary approach for studying the violence. A strong interest in the social reintegration process, through an ethnographic study, based on the actors backgrounds, their lives, experiences and their geographical location have provided information that will allow to know the reality of those who are living in the process, those who survive it and those who go on with their lives in society, and those who after doing it return to the armed groups. Population displaced by violence, refugees, has contributed to this study about their possibilities to return to the society or to be excluded by it. With this purpose, a theoretical and a documentary analysis as well as fieldwork have been done, trying to bring forward tools and guidelines to make some progress in developing effective solutions for social integration of Colombian armed conflict victims.

Diffraction by random Ronchi gratings

In this work, we obtain analytical expressions for the near-and far-field diffraction of random Ronchi diffraction gratings where the slits of the grating are randomly displaced around their periodical positions. We theoretically show that the effect of randomness in the position of the slits of the grating produces a decrease of the contrast and even disappearance of the self-images for high randomness level at the near field. On the other hand, it cancels high-order harmonics in far field, resulting in only a few central diffraction orders. Numerical simulations by means of the Rayleigh–Sommerfeld diffraction formula are performed in order to corroborate the analytical results. These results are of interest for industrial and technological applications where manufacture errors need to be considered.

Macroglial and retinal changes in hypercholesterolemic rabbits after normalization of cholesterol levels

This study evaluates hypercholesterolemic rabbits, examining the retinal changes in Müller cells and astrocytes as well as their variations after a period of normal blood-cholesterol values induced by a standard diet. New Zealand rabbits were divided into three groups: G0, fed a standard diet; G1A, fed a 0.5% cholesterol-enriched diet for 8 months; and G1B, fed as G1A followed by standard diet for 6 months. Eyes were processed for transmission electron microscopy and immunohistochemistry (GFAP). While G1B resembled G0 more than did G1A, they shared alterations with G1A: a) as in G1A, Müller cells were GFAP+, filled spaces left by axonal degeneration, formed glial scars and their nuclei were displaced to the nerve-fibre layer. The area occupied by the astrocytes associated with the nerve-fibre bundles (AANFB) and by perivascular astrocytes (PVA) in G1A and G1B was significantly lower than in controls. However, no significant differences in PVA were found between G1A and G1B. In G1B, type I PVA was absent and replaced by hypertrophic type II cells; b) Bruch's membrane (BM) was thinner in G1B than in G1A; c) the retinal pigment epithelium (RPE) cytoplasm contained fewer lipids in G1B than in G1A; d) in G1A and G1B choriocapillaris and retinal vessel showed alterations with respect to G0; e) cell death and axonal degeneration in the retina were similar in G1A and G1B. The substitution of a hyperlipemic diet by a standard one normalizes blood-lipid levels. However, the persistence of damage at retinal vessels and BM-RPE could trigger chronic ischemia.