Squatter settlements as social catalysts towards a sustainable urban development: a positive look at the case of Villa El Salvador, Lima-Perú

Se ha estimado que más de 900 millones de personas viven actualmente en asentamientos marginales en países en vías de desarrollo (Montgomery 2005); fenómeno que se originó a partir de un acelerado proceso de urbanización desencadenado por una masiva migración urbana (Johansson et al. 2011). El propósito de este documento es determinar e identificar aquellos atributos, factores, estrategias y políticas necesarias para aumentar la capacidad de auto-mejora de estos asentamientos para lograr convertirlos en lugares menos vulnerables, más resistentes y ambientalmente más responsables. El Caso de estudio de Villa El Salvador, ubicado en Lima-Perú, es analizado como evidencia de que las organizaciones de base y el modelo de ‘Auto-ayuda’ liderados por la propia comunidad son efectivos para un desarrollo urbano sustentable. Este análisis hace hincapié en la necesidad de cambiar la actitud hacia los ‘Pueblos Jóvenes’, descubriendo sus potencialidades para proveer vivienda asequible y desarrollo socio-económico para los más pobres. Las conclusiones intentan lograr un mejor entendimiento de esta problemática desde una perspectiva mucho más humana y positiva, con la esperanza de contribuir en el proceso de acrecentamiento e integración urbana de comunidades segregadas; una visión que demanda la incorporación de los pobladores como los catalizadores sociales necesarios para lograr un futuro más equitativo y sustentable.).It is estimated that more than 900 million of the total population of developing countries is living in squatter settlements (Montgomery 2005); phenomenon originated from the accelerated process of urbanisation unleashed by the massive migration of the poorer from rural to urban areas (Johansson et al. 2011). The purpose of this paper is to determine and identify those attributes, factors, strategies and policies necessary for boosting the upgrading capacity of slums in order to turn them into less vulnerable, more resilient and environmentally-oriented places. The case study of Villa El Salvador, a slum located in Lima-Peru, is analysed as a supporting evidence of effective grass-roots management and as an exemplary self-help model led by residents and community organisations. This analysis emphasizes the necessity to change the attitude towards squatter settlements, by unveiling their potential to provide affordable housing and socio-economic development to the poorer. Conclusions are intended to gain a better understanding of this problematic from a more positive and humanitarian perspective, with the hope of contributing with the accretion process and urban integration of segregated communities; a vision that demands the incorporation of dwellers as the social catalyst needed to achieve a more sustainable and equitable future.Eje 4: Construir las nuevas agendas socio-ambientales. Orientar y gestionar las transiciones y transformaciones urbanas.Facultad de Arquitectura y Urbanism

Squatter settlements as social catalysts towards a sustainable urban development: a positive look at the case of Villa El Salvador, Lima-Perú

Se ha estimado que más de 900 millones de personas viven actualmente en asentamientos marginales en países en vías de desarrollo (Montgomery 2005); fenómeno que se originó a partir de un acelerado proceso de urbanización desencadenado por una masiva migración urbana (Johansson et al. 2011). El propósito de este documento es determinar e identificar aquellos atributos, factores, estrategias y políticas necesarias para aumentar la capacidad de auto-mejora de estos asentamientos para lograr convertirlos en lugares menos vulnerables, más resistentes y ambientalmente más responsables. El Caso de estudio de Villa El Salvador, ubicado en Lima-Perú, es analizado como evidencia de que las organizaciones de base y el modelo de ‘Auto-ayuda’ liderados por la propia comunidad son efectivos para un desarrollo urbano sustentable. Este análisis hace hincapié en la necesidad de cambiar la actitud hacia los ‘Pueblos Jóvenes’, descubriendo sus potencialidades para proveer vivienda asequible y desarrollo socio-económico para los más pobres. Las conclusiones intentan lograr un mejor entendimiento de esta problemática desde una perspectiva mucho más humana y positiva, con la esperanza de contribuir en el proceso de acrecentamiento e integración urbana de comunidades segregadas; una visión que demanda la incorporación de los pobladores como los catalizadores sociales necesarios para lograr un futuro más equitativo y sustentable.).It is estimated that more than 900 million of the total population of developing countries is living in squatter settlements (Montgomery 2005); phenomenon originated from the accelerated process of urbanisation unleashed by the massive migration of the poorer from rural to urban areas (Johansson et al. 2011). The purpose of this paper is to determine and identify those attributes, factors, strategies and policies necessary for boosting the upgrading capacity of slums in order to turn them into less vulnerable, more resilient and environmentally-oriented places. The case study of Villa El Salvador, a slum located in Lima-Peru, is analysed as a supporting evidence of effective grass-roots management and as an exemplary self-help model led by residents and community organisations. This analysis emphasizes the necessity to change the attitude towards squatter settlements, by unveiling their potential to provide affordable housing and socio-economic development to the poorer. Conclusions are intended to gain a better understanding of this problematic from a more positive and humanitarian perspective, with the hope of contributing with the accretion process and urban integration of segregated communities; a vision that demands the incorporation of dwellers as the social catalyst needed to achieve a more sustainable and equitable future.Eje 4: Construir las nuevas agendas socio-ambientales. Orientar y gestionar las transiciones y transformaciones urbanas.Facultad de Arquitectura y Urbanism

The Augmented Lagrange Multiplier Method for Exact Recovery of Corrupted Low-Rank Matrices

This paper proposes scalable and fast algorithms for solving the Robust PCA problem, namely recovering a low-rank matrix with an unknown fraction of its entries being arbitrarily corrupted. This problem arises in many applications, such as image processing, web data ranking, and bioinformatic data analysis. It was recently shown that under surprisingly broad conditions, the Robust PCA problem can be exactly solved via convex optimization that minimizes a combination of the nuclear norm and the $\ell^1$-norm . In this paper, we apply the method of augmented Lagrange multipliers (ALM) to solve this convex program. As the objective function is non-smooth, we show how to extend the classical analysis of ALM to such new objective functions and prove the optimality of the proposed algorithms and characterize their convergence rate. Empirically, the proposed new algorithms can be more than five times faster than the previous state-of-the-art algorithms for Robust PCA, such as the accelerated proximal gradient (APG) algorithm. Moreover, the new algorithms achieve higher precision, yet being less storage/memory demanding. We also show that the ALM technique can be used to solve the (related but somewhat simpler) matrix completion problem and obtain rather promising results too. We further prove the necessary and sufficient condition for the inexact ALM to converge globally. Matlab code of all algorithms discussed are available at http://perception.csl.illinois.edu/matrix-rank/home.htmlComment: Please cite "Zhouchen Lin, Risheng Liu, and Zhixun Su, Linearized Alternating Direction Method with Adaptive Penalty for Low Rank Representation, NIPS 2011." (available at arXiv:1109.0367) instead for a more general method called Linearized Alternating Direction Method This manuscript first appeared as University of Illinois at Urbana-Champaign technical report #UILU-ENG-09-2215 in October 2009 Zhouchen Lin, Risheng Liu, and Zhixun Su, Linearized Alternating Direction Method with Adaptive Penalty for Low Rank Representation, NIPS 2011. (available at http://arxiv.org/abs/1109.0367

Squatter settlements as social catalysts towards a sustainable urban development: a positive look at the case of Villa El Salvador, Lima-Perú

Se ha estimado que más de 900 millones de personas viven actualmente en asentamientos marginales en países en vías de desarrollo (Montgomery 2005); fenómeno que se originó a partir de un acelerado proceso de urbanización desencadenado por una masiva migración urbana (Johansson et al. 2011). El propósito de este documento es determinar e identificar aquellos atributos, factores, estrategias y políticas necesarias para aumentar la capacidad de auto-mejora de estos asentamientos para lograr convertirlos en lugares menos vulnerables, más resistentes y ambientalmente más responsables. El Caso de estudio de Villa El Salvador, ubicado en Lima-Perú, es analizado como evidencia de que las organizaciones de base y el modelo de ‘Auto-ayuda’ liderados por la propia comunidad son efectivos para un desarrollo urbano sustentable. Este análisis hace hincapié en la necesidad de cambiar la actitud hacia los ‘Pueblos Jóvenes’, descubriendo sus potencialidades para proveer vivienda asequible y desarrollo socio-económico para los más pobres. Las conclusiones intentan lograr un mejor entendimiento de esta problemática desde una perspectiva mucho más humana y positiva, con la esperanza de contribuir en el proceso de acrecentamiento e integración urbana de comunidades segregadas; una visión que demanda la incorporación de los pobladores como los catalizadores sociales necesarios para lograr un futuro más equitativo y sustentable.).It is estimated that more than 900 million of the total population of developing countries is living in squatter settlements (Montgomery 2005); phenomenon originated from the accelerated process of urbanisation unleashed by the massive migration of the poorer from rural to urban areas (Johansson et al. 2011). The purpose of this paper is to determine and identify those attributes, factors, strategies and policies necessary for boosting the upgrading capacity of slums in order to turn them into less vulnerable, more resilient and environmentally-oriented places. The case study of Villa El Salvador, a slum located in Lima-Peru, is analysed as a supporting evidence of effective grass-roots management and as an exemplary self-help model led by residents and community organisations. This analysis emphasizes the necessity to change the attitude towards squatter settlements, by unveiling their potential to provide affordable housing and socio-economic development to the poorer. Conclusions are intended to gain a better understanding of this problematic from a more positive and humanitarian perspective, with the hope of contributing with the accretion process and urban integration of segregated communities; a vision that demands the incorporation of dwellers as the social catalyst needed to achieve a more sustainable and equitable future.Eje 4: Construir las nuevas agendas socio-ambientales. Orientar y gestionar las transiciones y transformaciones urbanas.Facultad de Arquitectura y Urbanism

Proliferation of cerebellar precursor cells is negatively regulated by nitric oxide in newborn rat.

The diffusible messenger, nitric oxide plays multiple roles in neuroprotection, neurodegeneration and brain plasticity. Its involvement in neurogenesis has been disputed, on the basis of results on models in vivo and in culture. We report here that pharmacological blockade of nitric oxide production in rat pups resulted, during a restricted time window of the first three postnatal days, in increased cerebellar proliferation rate, as assessed through tritiated thymidine or BrdU incorporation into DNA. This was accompanied by increased expression of Myc, a transcription factor essential for cerebellar development, and of the cell cycle regulating gene, cyclin D1. These effects were mediated downstream by the nitric oxide-dependent second messenger, cGMP. Schedules of pharmacological NO deprivation targeted to later developmental stages (from postnatal day 3 to 7), no longer increased proliferation, probably because of partial escape of the cGMP level from nitric oxide control. Though limited to a brief temporal window, the proliferative effect of neonatal nitric oxide deprivation could be traced into adulthood. Indeed, the number of BrdU-labeled surviving cells, most of which were of neuronal phenotype, was larger in the cerebellum of 60-day-old rats that had been subjected to NO deprivation during the first three postnatal days than in control rats. Experiments on cell cultures from neonatal cerebellum confirmed that nitric oxide deprivation stimulated proliferation of cerebellar precursor cells and that this effect was not additive with the proliferative action of sonic hedgehog peptide. The finding that nitric oxide deprivation during early cerebellar neurogenesis, stimulates a brief increase in cell proliferation may contribute to a better understanding of the controversial role of nitric oxide in brain development

N=1 de Sitter Supersymmetry Algebra

Recalling the universal covering group of de Sitter, the transformation properties of the spinor fields $\psi(x)$ and ${\bar\psi}(x)$, in the ambient space notation, are presented in this paper. The charge conjugation symmetry of the de Sitter spinor field is then discussed in the above notation. Using this spinor field and charge conjugation, de Sitter supersymmetry algebra in the ambient space notation has been established. It is shown that a novel dS-superalgebra can be attained by the use of spinor field and charge conjugation in the ambient space notation.Comment: 8 pages, LaTeX, some details adde

Long-term effect of neonatal inhibition of APP gamma-secretase on hippocampal development in the Ts65Dn mouse model of Down syndrome

Neurogenesis impairment is considered a major determinant of the intellectual disability that characterizes Down syndrome (DS), a genetic condition caused by triplication of chromosome 21. Previous evidence obtained in the Ts65Dn mouse model of DS showed that the triplicated gene APP (amyloid precursor protein) is critically involved in neurogenesis alterations. In particular, excessive levels of AICD (amyloid precursor protein intracellular domain) resulting from APP cleavage by gamma-secretase increase the transcription of Ptch1, a Sonic Hedgehog (Shh) receptor that keeps the mitogenic Shh pathway repressed. Previous evidence showed that neonatal treatment with ELND006, an inhibitor of gamma-secretase, reinstates the Shh pathway and fully restores neurogenesis in Ts65Dn pups. In the framework of potential therapies for DS, it is extremely important to establish whether the positive effects of early intervention are retained after treatment cessation. Therefore, the goal of the current study was to establish whether early treatment with ELND006 leaves an enduring trace in the brain of Ts65Dn mice. Ts65Dn and euploid pups were treated with ELND006 in the postnatal period P3-P15 and the outcome of treatment was examined at ~ one month after treatment cessation. We found that in treated Ts65Dn mice the pool of proliferating cells in the hippocampal dentate gyrus (DG) and total number of granule neurons were still restored as was the number of pre- and postsynaptic terminals in the stratum lucidum of CA3, the site of termination of the mossy fibers from the DG. Accordingly, patch-clamp recording from field CA3 showed functional normalization of the input to CA3. Unlike in field CA3, the number of pre- and postsynaptic terminals in the DG of treated Ts65Dn mice was no longer fully restored. The finding that many of the positive effects of neonatal treatment were retained after treatment cessation provides proof of principle demonstration of the efficacy of early inhibition of gamma-secretase for the improvement of brain development in DS

THGEM operation in Ne and Ne/CH4

The operation of Thick Gaseous Electron Multipliers (THGEM) in Ne and Ne/CH4 mixtures, features high multiplication factors at relatively low operation potentials, in both single- and double-THGEM configurations. We present some systematic data measured with UV-photons and soft x-rays, in various Ne mixtures. It includes gain dependence on hole diameter and gas purity, photoelectron extraction efficiency from CsI photocathodes into the gas, long-term gain stability and pulse rise-time. Position resolution of a 100x100 mm^2 X-rays imaging detector is presented. Possible applications are discussed.Comment: Submitted to JINST, 25 pages, 33 figure

Inhibition of oxidative metabolism leads to p53 genetic inactivation and transformation in neural stem cells

The final published version can be found here: http://dx.doi.org/10.1073/pnas.141316511

Molecular Architectures of Trimeric SIV and HIV-1 Envelope Glycoproteins on Intact Viruses: Strain-Dependent Variation in Quaternary Structure

The initial step in target cell infection by human, and the closely related simian immunodeficiency viruses (HIV and SIV, respectively) occurs with the binding of trimeric envelope glycoproteins (Env), composed of heterodimers of the viral transmembrane glycoprotein (gp41) and surface glycoprotein (gp120) to target T-cells. Knowledge of the molecular structure of trimeric Env on intact viruses is important both for understanding the molecular mechanisms underlying virus-cell interactions and for the design of effective immunogen-based vaccines to combat HIV/AIDS. Previous analyses of intact HIV-1 BaL virions have already resulted in structures of trimeric Env in unliganded and CD4-liganded states at ∼20 Å resolution. Here, we show that the molecular architectures of trimeric Env from SIVmneE11S, SIVmac239 and HIV-1 R3A strains are closely comparable to that previously determined for HIV-1 BaL, with the V1 and V2 variable loops located at the apex of the spike, close to the contact zone between virus and cell. The location of the V1/V2 loops in trimeric Env was definitively confirmed by structural analysis of HIV-1 R3A virions engineered to express Env with deletion of these loops. Strikingly, in SIV CP-MAC, a CD4-independent strain, trimeric Env is in a constitutively “open” conformation with gp120 trimers splayed out in a conformation similar to that seen for HIV-1 BaL Env when it is complexed with sCD4 and the CD4i antibody 17b. Our findings suggest a structural explanation for the molecular mechanism of CD4-independent viral entry and further establish that cryo-electron tomography can be used to discover distinct, functionally relevant quaternary structures of Env displayed on intact viruses