¿La mano dura disminuye los homicidios? El caso de Venezuela

Este artículo examina la eficacia de las políticas de «mano dura» en la reducción de homicidios –en particular las que implican la violencia policial– a partir del estudio del caso de Venezuela en el período 2012-2015. Aun cuando las políticas de mano dura suponen un conjunto de estrategias y discursos en torno al delito y la respuesta institucional frente a él, en este trabajo se atiende exclusivamente a las intervenciones policiales que implican un aumento de la coacción y la violencia como fórmula para enfrentar la criminalidad. Durante estos años, se han ensayado en Venezuela políticas que implican un aumento de la violencia policial con el pretexto de batir los altos niveles de violencia delictiva; sin embargo, lejos de los esperados efectos de reducción de la violencia y los homicidios, estos se han incrementado significativamente

Selfish and Altruistic Bacterial Populations Maximize Fitness Under Stress by Local Segregation

Landscapes in ecology have a profound influence on the adaption and evolution of competing populations for resources. We are interested in how altruistic populations survive in the presence of selfish individuals in a non-stirred, closed and complex nutrient landscape. Well-stirred (landscape-free) but closed environments have a depressing future when selfish individuals arise in a population, a fate known as the tragedy of the Commons. Over-exploitation of a well-stirred communal habitat by selfish individuals which do not follow rules of communal self-regulation ends up in the elimination (extinction) of both the original altruistic inhabitants and the selfish population. In the context of bacterial population, the Commons tragedy that occurs is the consumption of limited resources by the individuals, resulting in metabolic stressing of the bacteria and growth advantages to be gained by defection from a ``social contract" of altruistic cooperation. There is no avoidance of this tragedy and the collapse of an original altruistic wild-type population by an emergent selfish population in a well-stirred but closed environment is inevitable. However, there is a fundamental difference between resource exploitation in a well-stirred homogenous commons and in a heterogenous landscape of nutrients which is not stirred. We show here using a non-stirred nanofabricated habitat landscape that altruists and selfish bacteria can in fact coexist, that they can maintain phenotype diversity and avoid the tragedy of the Commons. This emergent spatial segregation of competing populations under stress greatly changes, we believe, our perception of the true sophistication of bacterial response to stress and competition, and has broad implications for the adaptive strategies of higher organisms under stress in complex environments

Population dynamics of the rat tapeworm, 'Hymenolepis Diminuta'

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Adaptive response and enlargement of dynamic range

Many membrane channels and receptors exhibit adaptive, or desensitized, response to a strong sustained input stimulus, often supported by protein activity-dependent inactivation. Adaptive response is thought to be related to various cellular functions such as homeostasis and enlargement of dynamic range by background compensation. Here we study the quantitative relation between adaptive response and background compensation within a modeling framework. We show that any particular type of adaptive response is neither sufficient nor necessary for adaptive enlargement of dynamic range. In particular a precise adaptive response, where system activity is maintained at a constant level at steady state, does not ensure a large dynamic range neither in input signal nor in system output. A general mechanism for input dynamic range enlargement can come about from the activity-dependent modulation of protein responsiveness by multiple biochemical modification, regardless of the type of adaptive response it induces. Therefore hierarchical biochemical processes such as methylation and phosphorylation are natural candidates to induce this property in signaling systems.Comment: Corrected typos, minor text revision

Large Quark Rotations, Neutrino mixing and Proton Decay

Right-handed (RH) rotations do not play a role in the Standard Model, and only the differences of the LH mixing angles are involved in {\bf V}_{\scr \textrm{CKM}}. This leads to the huge freedom in the fermionic mass matrices. However, that is no more true in extensions of the Standard Model. For example in GUTs large RH rotations of the quarks can be related to the observed large neutrino mixing or in particular, all mixing angles are relevant for the proton decay. We present a simple realistic non-SUSY SO(10) GUT with large RH and LH mixing and study the corresponding nucleon decay rates.Comment: Latex2e file with 3 PS figures, minor corrections,the final version to be published in Nucl. Phys.

Exact asymptotic analysis for metapopulation dynamics on correlated dynamic landscapes

We compute the mean patch occupancy for a stochastic, spatially explicit patch-occupancy metapopulation model on a dynamic, correlated landscape, using a mathematically exact perturbation expansion about a mean-field limit that applies when dispersal range is large. Stochasticity in the metapopulation and landscape dynamics gives negative contributions to patch occupancy, the former being more important at high occupancy and the latter at low occupancy. Positive landscape correlations always benefit the metapopulation, but are only significant when the correlation length is comparable to, or smaller than, the dispersal range. Our analytical results allow us to consider the importance of spatial kernels in all generality. We find that the shape of the landscape correlation function is typically unimportant, and that the variance is overwhelmingly the most important property of the colonisation kernel. However, short-range singularities in either the colonisation kernel or landscape correlations can give rise to qualitatively different behaviour

Solar Calendar, And Other Ways of Marking Time

At the end of his life, Pierre Hadot was a professor at the Collège de France — a “professor’s professor” — and he helped Michel Foucault, most famously, conceptualize ethics. Hadot devoted his career to recovering the ancient conception of philosophy, according to which the discourses of universities are but a fragment of what philosophy is. His engagement with this theme helped Bendik-Keymer understand and develop a personal counter-culture to his academic work, a kind of original academics truer to the idea of the philosophical school Plato first developed in his Ἀκαδήµεια. But while Plato’s school developed a useful form of life, it had an ambivalent relation to democracy and to everyday people. Whereas Plato was in some ways one of the first egalitarians by merit (especially concerning women), he was also deeply classist in his categorization of intellectual potentials. He effectively thought some people were stupid by nature, having no philosophical worth. Hence the Ἀκαδήµεια existed outside the city, in practice exclusive and somewhat sequestered. To some extent, Plato’s vision of philosophy — at least as explained by Hadot — had the practical point of philosophy right, but this point still needed to be rendered thoroughly democratic in the polyphony and multiple intelligences of people. Doing so coheres with what Foucault was after in his application of Hadot. It is also what Bendik-Keymer is after — to extract what is good from original academics and make it democratic, as opposed to dumbing people down

A Minimal Participatory Condition on Democratic Right

There are two problems that plagued the construction of representation in the U.S. constitution leading up to its ratification, and these two problems could conceivably be addressed through a single, practical condition on democratic participation. The first problem is the problem of poor judgment. The second problem is the problem of remote representation. In this essay, I will propose that both problems be partially but substantially addressed through a minimum participatory condition on democratic right. Let me first set up each problem textually