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Las inundaciones se encuentran entre los peligros naturales más recurrentes y devastadores, al afectar vidas humanas y causar graves daños económicos en todo el mundo. Las regiones áridas y semiáridas son particularmente vulnerables a tormentas intensas en periodos cortos debido a que provocan inundaciones súbitas. Estas regiones representan un 30% del área mundial y están habitadas por 20% de la población. El objetivo principal del presente estudio es estimar la tormenta de diseño para los periodos de retorno de 20, 50, 100 y 500 años en la región semiárida de la subcuenca del Río Nuevo, a fin de determinar las áreas de inundación del cauce principal. Se propone un modelo integrado, que consiste en desarrollar un acoplamiento del modelo hidrológico e hidráulico para diferentes periodos de retorno, alimentados con un Análisis Regional de Frecuencia (ARF), utilizando el enfoque de los L-momentos, empleando los programas HEC-HMS y HEC-RAS. Las áreas de inundación obtenidas de 190.55 a 237.83 ha y profundidades desde 0.10 hasta 6.0 metros comprometen la infraestructura urbana de la ciudad. Los resultados de esta investigación pueden ser utilizados por organismos encargados de la planeación urbana para disminuir riesgos de inundación.

In this examination of Mexican-American bilingual college writers, it is argued that implicit language ideologies, common misconceptions about bidialectalism/bilingualism, and the classroom attitudinal domain subvert the success of ethnolinguistic minority students. The author designed and conducted a randomized language attitude survey (N = 195) of 1st-year composition students on the assumption that language attitudes, reflective of the social/ethnic/linguistic polarization of south Texas, exist inside the English classroom. Findings correlate the multiple ethnolinguistic identities of this student population with language myth adherence. Results reveal the tendency among college writers for subscription to various language myths: dialect misconception, English bias, language purity myth, literacy myth, misconception of oral performance. [ABSTRACT FROM AUTHOR]

In the Amazon basin, indigenous forest-dwelling communities typically suffer from a high burden of infectious diseases, including malaria. Difficulties in accessing these isolated ethnic groups, such as the semi-nomadic Yanomami, make official malaria data largely underestimated. In the current study, we longitudinally surveyed microscopic and submicroscopic malaria infection in four Yanomami villages of the Marari community in the northern-most region of the Brazilian Amazon. Malaria parasite species-specific PCR-based detection of ribosomal and non-ribosomal targets showed that approximately 75% to 80% of all malaria infections were submicroscopic, with the ratio of submicroscopic to microscopic infection remaining stable over the 4-month follow-up period. Although the prevalence of malaria infection fluctuated over time, microscopically-detectable parasitemia was only found in children and adolescents, presumably reflecting their higher susceptibility to malaria infection. As well as temporal variation, the prevalence of malaria infection differed significantly between villages (from 1% to 19%), demonstrating a marked heterogeneity at micro-scales. Over the study period, Plasmodium vivax was the most commonly detected malaria parasite species, followed by P. malariae, and much less frequently P. falciparum. Consecutive blood samples from 859 out of the 981 studied Yanomami showed that malaria parasites were detected in only 8% of the previously malaria-positive individuals, with most of them young children (median age 3 yrs). Overall, our results show that molecular tools are more sensitive for the identification of malaria infection among the Yanomami, which is characterized by heterogeneous transmission, a predominance of low-density infections, circulation of multiple malaria parasite species, and a higher susceptibility in young children. Our findings are important for the design and implementation of the new strategic interventions that will be required for the elimination of malaria from isolated indigenous populations in Latin America.

Se presentan los resultados que demuestran la influencia del efecto de borde al emplear modelos híbridos Wavelet Neuronal o Wavelet neurodifuso para pronosticar series de tiempo mensuales de lámina de precipitación con un mes de anticipación. Para la implementación de los modelo se utiliza la información de la estación climatológica ubicada en la presa Emilio López Zamora en la ciudad de Ensenada, al noroeste del Estado de Baja California, México. El estudio combina cuatro métodos: a) Transformada Wavelet Discreta con el algoritmo de Mallat (DWT): b) Transformada Wavelet Discreta de Máxima Superposición (MODWT); c) Feed Forward Back Propagation (FFBP), y, d) Adaptive-Networkbased Fuzzy Inference System (ANFIS). Se utilizan dos enfoques de preprocesamiento utilizados en la actualidad en la literatura para pronosticar series climáticas de variables hidrológicas. En el primer enfoque se emplean cuatro métodos para realizar la convolución de la transformada y se discute su relación con el fenómeno del efecto de borde. Los resultados muestran que el modelo híbrido utilizado influye de manera significativa para mejorar el entrenamiento de la red con fines de predicción, sin embargo, para la etapa de pronóstico sucede lo contrario debido al efecto de borde. En el segundo enfoque se encuentra que la serie de tiempo se tiene que reconstruir con coeficientes wavelet de escalas, que corresponden a un periodo de cinco años, y los resultados muestran que existe una componente de ruido significativa en la señal. Por último, se encontró que ANFIS autónomo es el método más sencillo y recomendable de utilizar para este tipo de series de tiempo.

Latin America and the Caribbean (LAC) has the least carbon-intensive electricity sector of any region in the world, as hydropower remains the largest source of electricity. But are current plans consistent with the international climate change goals laid out in the Paris Agreement? In this paper, we assess committed CO _2 emissions from existing and planned power plants in LAC. Those are the carbon emissions that would result from the operation of fossil-fueled power plants during their typical lifetime. Committed emissions from existing power plants are close to 6.9 Gt of CO _2 . Building and operating all power plants that are announced, authorized, being procured, or under construction would result in 6.7 Gt of CO _2 of additional commitments (for a total of 13.6 Gt of CO _2 ). Committed emissions are above average IPCC assessments of cumulative emissions from power generation in LAC consistent with international temperature targets. To meet average carbon budgets from IPCC, 10%–16% of existing fossil-fueled power plants would need to be closed before the end of their technical lifespan. Our results suggest that building more fossil-fueled power plants in the region could jeopardize the achievement of the Paris Agreement temperature targets.

Writing program administrators need to be as concerned about sustaining the cultural ecologies of our communities as we are about the material economies of our institutions -- we need to attend to the diverse linguistic and rhetorical ecologies within which twenty-first century student writers are exercising agency. In order to respond productively, ethically, and appropriately to the increasingly diverse language and literacy practices of 21st century college writers, this profile will focus on a program that reconfigures the intellectual operating spaces of Composition Studies by training junior writing program administrators in how to promote rhetorical action alongside the study of composition pedagogy and praxis and by advocating on behalf of ethno-linguistically diverse communities within and beyond the university. [ABSTRACT FROM AUTHOR]