261 research outputs found

    Analysis of human physical vulnerability using static equilibrium techniques of a Hazard flood for the determination of unsafe areas in the city of Catacaos - Piura, Peru

    Get PDF
    Heavy rains and El Nio phenomenon are recurring natural phenomena at a national level. These can cause floods due to the overflowing of rivers, which, when close to cities, can cause both human and material losses. The district of Catacaos, located in the city of Piura, was the one with the highest number of injuries due to the flood caused by El Nio phenomenon in 2017. This phenomenon causes a large amounts of rainfalls due to the presence of abnormally warm waters along the northern coast of Peru [1]. It is for this reason that the need arose to carry out an analysis of the physical vulnerability due to instability of people through static equilibrium, in said district, in order to present maps of unsafe areas in the face of this phenomenon. In this investigation, flood hazard maps are generated simulating the one presented in 2017, using 2D hydraulic modeling. For the generation of vulnerability curves, the instability analysis is performed by moment and drag force. Finally, maps with unsafe areas are made using ArcGis software. Where the results obtained indicate that 29.37% of the city was flooded. Likewise, the vulnerability maps generated show us that women and men over 18 years of age in the city of Catacaos would be vulnerable to dragging and overturning in the face of floods in 16.54% and 13.21%, respectively, of the total studied area. This information will be useful for the development of future evacuation plans during floods, carried out by national entities. © Published under licence by IOP Publishing Ltd

    Levantamento geofísico no "Abanico el Paso" Cochabamba-Bolívia

    Get PDF
    Vertical electrical soundings were measured in the Cochabamba sedimentary basin at several alluvial fans (locally called "abanicos"). This paper presents data from the Abanico El Paso. This research attempted to correlate geophysical data with the presence of paleo-channels inside the alluvial fans. These fans, mostly concentrated at the foot of the Cordilheira Ocidental, are about 1 km across and up to 4 km long. Data from deep wells were used to establish a correlation between the geophysical and hydrogeological data. The specific yield of the deep wells can be correlated with the grain size of the sediments. Apparent resistivity values of the vertical electrical soundings, for several AB/2 spacings were used to construct resistivity profiles, were the distance between each measured points corresponds to the distance between the points where a vertical electrical sounding was measured. Once again, the eletro-resitivity method demonstrated its potentiality as an exploration tool.Na bacia sedimentar de Cochabamba-Bolívia, localizada na província de mesmo nome, encontra-se situada a cidade de Cochabamba que utiliza grande volume de água subterrânea para seu abastecimento e irrigação da zona agrícola. Trata-se de uma bacia intramontana limitada pelas Cordilheiras Ocidental e Oriental. Nos sopés da Cordilheira Ocidental encontram-se localizados vários leques alimonares (abanicos) constituídos de material grosseiro, mesclado com material mais fino, representando importantes fontes de água subterrânea. Um levantamento geofísico empregando a eletrorresistividade, em seu procedimento de sondagem elétrica vertical, foi executado com o objetivo de verificar a possibilidade de serem detectadas as presenças de paleo-canais. Estes paleo-canais correspondem às melhores partes para a construção de poços profundos, dadas às altas permeabilidades e porosidades aí reinantes. Para a aferição dos dados geofísicos, foram utilizados dados de poços perfurados no local, onde foram determinadas as porcentagens de cascalho areia e argila. Procurou-se estabelecer uma correlação entre a vazão específica dos poços e seus teores de areia + cascalho. Com dados de resistividade aparente das sondagens elétricas verticais, foram construidos gráficos de caminhamento elétrico, para diferentes espaçamentos AB/2 (como se diversos caminhamentos tivessem sido realizados com pontos de medida a cada ponto da sondagem elétrica vertical). Estes perfis mostram a distribuição lateral da resistividade que pode ser correlacionada com a litologia e por conseguinte, com as possibilidades de determinar locais mais favoráveis à construção de poços profundos

    Novel evolutionary algorithm identifies interactions driving infestation of triatoma dimidiata, a chagas disease vector

    Get PDF
    Chagas disease is a lethal, neglected tropical disease. Unfortunately, aggressive insecticide-spraying campaigns have not been able to eliminate domestic infestation of Triatoma dimidiata, the native vector in Guatemala. To target interventions toward houses most at risk of infestation, comprehensive socioeconomic and entomologic surveys were conducted in two towns in Jutiapa, Guatemala. Given the exhaustively large search space associated with combinations of risk factors, traditional statistics are limited in their ability to discover risk factor interactions. Two recently developed statistical evolutionary algorithms, specifically designed to accommodate risk factor interactions and heterogeneity, were applied to this large combinatorial search space and used in tandem to identify sets of risk factor combinations associated with infestation. The optimal model includes 10 risk factors in what is known as a third-order disjunctive normal form (i.e., infested households have chicken coops AND deteriorated bedroom walls OR an accumulation of objects AND dirt floors AND total number of occupants 3 5 AND years of electricity 3 5 OR poor hygienic condition ratings AND adobe walls AND deteriorated walls AND dogs). Houses with dirt floors and deteriorated walls have been reported previously as risk factors and align well with factors currently targeted by Ecohealth interventions to minimize infestation. However, the tandem evolutionary algorithms also identified two new socioeconomic risk factors (i.e., households having many occupants and years of electricity 3 5). Identifying key risk factors may help with the development of new Ecohealth interventions and/or reduce the survey time needed to identify houses most at risk

    Liver-specific methionine adenosyltransferase MAT1A gene expression is associated with a specific pattern of promoter methylation and histone acetylation: implications for MAT1A silencing during transformation

    Get PDF
    Methionine adenosyltransferase (MAT) is the enzyme that catalyzes the synthesis of S-adenosylmethionine (AdoMet), the main donor of methyl groups in the cell. In mammals MAT is the product of two genes, MAT1A and MAT2A. MAT1A is expressed only in the mature liver whereas fetal hepatocytes, extrahepatic tissues and liver cancer cells express MAT2A. The mechanisms behind the tissue and differentiation state specific MAT1A expression are not known. In the present work we examined MAT1A promoter methylation status by means of methylation sensitive restriction enzyme analysis. Our data indicate that MAT1A promoter is hypomethylated in liver and hypermethylated in kidney and fetal rat hepatocytes, indicating that this modification is tissue specific and developmentally regulated. Immunoprecipitation of mononucleosomes from liver and kidney tissues with antibodies mainly specific to acetylated histone H4 and subsequent Southern blot analysis with a MAT1A promoter probe demonstrated that MAT1A expression is linked to elevated levels of chromatin acetylation. Early changes in MAT1A methylation are already observed in the precancerous cirrhotic livers from rats, which show reduced MAT1A expression. Human hepatoma cell lines in which MAT1A is not expressed were also hypermethylated at this locus. Finally we demonstrate that MAT1A expression is reactivated in the human hepatoma cell line HepG2 treated with 5-aza-2'-deoxycytidine or the histone deacetylase inhibitor trichostatin, suggesting a role for DNA hypermethylation and histone deacetylation in MAT1A silencing

    Dog skin parasite load, TLR-2, IL-10 and TNF-α expression and infectiousness

    Get PDF
    Visceral leishmaniosis is a zoonotic disease that is transmitted by Lutzomyia longipalpis sandflies. Dogs are the main peri-urban reservoir of the disease, and progression of canine leishmaniosis is dependent on the type of immune response elaborated against the parasite. Type 1 immunity is characterized by effective cellular response, with production of pro-inflammatory cytokines such as tumour necrosis factor alpha (TNF-α). In contrast, Type 2 immunity is predominantly humoral, associated with progression of the disease and mediated by anti-inflammatory cytokines such as interleukin 10 (IL-10). Although seemly important in the dynamics of leishmaniosis, other gene products such as toll-like receptor 2 (TRL-2) and inducible nitric oxide synthase (iNOS) exert unclear roles in the determination of the type of immune response. Given that the dog skin serves as a micro-environment for the multiplication of Leishmania spp., we investigated the parasite load and the expression of TLR-2, iNOS, IL-10 and TNF-α in the skin of 29 infected and 8 control dogs. We found that increased parasite load leads to upregulation of TLR-2, IL-10 and TNF-α, indicating that abundance of these transcripts is associated with infection. We also performed a xenodiagnosis to demonstrate that increased parasitism is a risk factor for infectiousness to sandflies

    EPDR1 up-regulation in human colorectal cancer is related to staging and favours cell proliferation and invasiveness

    Get PDF
    The finding of novel molecular markers for prediction or prognosis of invasiveness in colorectal cancer (CRC) constitutes an appealing challenge. Here we show the up-regulation of EPDR1 in a prospective cohort of 101 CRC patients, in a cDNA array of 43 patients and in in silico analyses. EPDR1 encodes a protein related to ependymins, a family of glycoproteins involved in intercellular contacts. A thorough statistical model allowed us to conclude that the gene is significantly up-regulated in tumour tissues when compared with normal mucosa. These results agree with those obtained by the analysis of three publicly available databases. EPDR1 up-regulation correlates with the TNM staging parameters, especially T and M. Studies with CRC cell lines revealed that the methylation of a CpG island controls EPDR1 expression. siRNA knocking-down and overexpression of the gene following transient plasmid transfection, showed that EPDR1 favours cell proliferation, migration, invasiveness and adhesion to type I collagen fibres, suggesting a role in epithelial to mesenchymal transition. Both statistical and functional analysis correlated EPDR1 overexpression with invasiveness and dissemination of tumour cells, supporting the inclusion of EPDR1 in panels of genes used to improve molecular subtyping of CRC. Eventually, EPDR1 may be an actionable target.Fil: Gimeno Valiente, F.. No especifíca;Fil: Riffo Campos, Á. L.. Universidad de La Frontera; ChileFil: Ayala, G.. Universidad de Valencia; EspañaFil: Tarazona, N.. Universidad de Valencia; EspañaFil: Gambardella, V.. Universidad de Valencia; EspañaFil: Rodríguez, Fernanda Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Huerta, M.. Universidad de Valencia; EspañaFil: Martínez-Ciarpaglini, C.. Universidad de Valencia; EspañaFil: Montón Bueno, J.. Universidad de Valencia; EspañaFil: Roselló, S.. Universidad de Valencia; EspañaFil: Roda, D.. Universidad de Valencia; EspañaFil: Cervantes, A.. Universidad de Valencia; EspañaFil: Franco, L.. Universidad de Valencia; EspañaFil: López Rodas, G.. Universidad de Valencia; EspañaFil: Castillo, J.. Universidad de Valencia; Españ

    Adjuvant nivolumab versus ipilimumab (CheckMate 238 trial): Reassessment of 4-year efficacy outcomes in patients with stage III melanoma per AJCC-8 staging criteria

    Get PDF
    Nivolumab was approved as adjuvant therapy for melanoma based on data from CheckMate 238, which enrolled patients per American Joint Committee on Cancer version 7 (AJCC-7) criteria. Here, we analyse long-term outcomes per AJCC-8 staging criteria compared with AJCC-7 results to inform clinical decisions for patients diagnosed per AJCC-8
    corecore