9,170 research outputs found
Vulnerability of the agricultural sector to climate change: The development of a pantropical Climate Risk Vulnerability Assessment to inform sub-national decision making
As climate change continues to exert increasing pressure upon the livelihoods and agricultural sector of many developing and developed nations, a need exists to understand and prioritise at the sub national scale which areas and communities are most vulnerable. The purpose of this study is to develop a robust, rigorous and replicable methodology that is flexible to data limitations and spatially prioritizes the vulnerability of agriculture and rural livelihoods to climate change. We have applied the methodology in Vietnam, Uganda and Nicaragua, three contrasting developing countries that are particularly threatened by climate change. We conceptualize vulnerability to climate change following the widely adopted combination of sensitivity, exposure and adaptive capacity. We used Ecocrop and Maxent ecological models under a high emission climate scenario to assess the sensitivity of the main food security and cash crops to climate change. Using a participatory approach, we identified exposure to natural hazards and the main indicators of adaptive capacity, which were modelled and analysed using geographic information systems. We finally combined the components of vulnerability using equal-weighting to produce a crop specific vulnerability index and a final accumulative score. We have mapped the hotspots of climate change vulnerability and identified the underlying driving indicators. For example, in Vietnam we found the Mekong delta to be one of the vulnerable regions due to a decline in the climatic suitability of rice and maize, combined with high exposure to flooding, sea level rise and drought. However, the region is marked by a relatively high adaptive capacity due to developed infrastructure and comparatively high levels of education. The approach and information derived from the study informs public climate change policies and actions, as vulnerability assessments are the bases of any National Adaptation Plans (NAP), National Determined Contributions (NDC) and for accessing climate finance
Evaluation of control strategies for the spread of citrus greening
Huanglongbing, also known as citrus greening, is a vector-based disease in citrus (with no cure known to date) that has drastically affected the citrus production in Florida in less than a decade and has been recently detected in Texas and California. In this paper, an epidemic model of the spatial spread of the disease is implemented among commercial and residential groves by taking into consideration the diffusion patterns of the psyllid vectors. A system of differential equations resembling one for malaria infection in humans is derived to evaluate different control methods such as quarantine, treatment, removal, foliar treatment, and pest control, among others. Using numerical techniques to analyze location data we determine the optimal techniques for limiting the spread of the disease. Finally, we measure the effect non-commercial trees have in carrying the infection over longer distances even if control measures have been established in commercial groves
Notes on the proof of the van der Waerden permanent conjecture
The permanent of an matrix with real entries is defined by the sum where denotes the symmetric group on the -element set . In this creative component we survey some known properties of permanents, calculation of permanents for particular types of matrices and their applications in combinatorics and linear algebra. Then we follow the lines of van Lint\u27s exposition of Egorychev\u27s proof for the van der Waerden\u27s conjecture on the permanents of doubly stochastic matrices. The purpose of this component is to provide elementary proofs of several interesting known facts related to permanents of some special matrices. It is an expository survey paper in nature and reports no new findings
Social class, marginality and self-assessed health: a cross-sectional analysis of the health gradient in Mexico
<p>Abstract</p> <p>Background</p> <p>Examining the association between social inequality and health is not new. However, there is little empirical evidence of this association in the Latin American literature, much less from the Mexican scholars. Its research, including the one conducted in Mexico, has mostly followed a theoretical approach and has not been able to provide strong empirical evidence of their important theoretical and conceptual contributions, mainly because reliable, complete and valid data are unavailable.</p> <p>Methods</p> <p>To empirically examine the gradient effect of social class on self-rated health in Mexico, a secondary cross-sectional mixed-level analysis was designed. Using individual level data from the Second National Health Survey (ENSA II), social class categories were specified following a stratification approach according to the occupation and education indicators available from ENSA II. Two types of categories were made, one for t urban and one for the rural labor force. Two indicators of perceived health status were used as health outcomes: self-assessed health and reported morbidity. Furthermore, the marginality index, an indicator of relative deprivation was used to examine its contextual effect at the state and regional level. The analysis was conducted using logistic multivariate models.</p> <p>Results</p> <p>The cross-sectional analysis showed a gradient effect of social class for good assessed-health. Relative to the low urban class, the odds ratio (OR) for a good perception of health for individuals belonging to the high urban class was 2.9 (95% confidence interval: 2.1–3.9). The OR for the middle high class was 2.8 (95% confidence interval: 2.4–3.4), while the OR for the middle low class was 1.8 (95% confidence interval: 1.6–2.1). However, for the rural labour force an OR of 1.5 was only significant between the high class who considered their health as good relative to the low class (95% confidence interval: 1.02–2.2). At the aggregate level, the results also showed individuals living in deprived regions were less likely to report their health as good than individuals living in relatively less deprived ones, OR = 0.6 (95% confidence interval: 0.4–0.7).</p> <p>Conclusion</p> <p>Overall, the findings of this study provided empirical evidence that social inequality negatively influences health through a differential exposure and an unequal distribution of resources across the class spectrum: the lower the social class, the poorer the perception of health. The results also showed that living in more deprived regions had a further negative effect on health. From a policy perspective, the gradient effects of social class suggest that non-targeted policies should be designed to address both material conditions at the individual level as well as deprived living conditions at higher levels of aggregation to improve health across the social spectrum.</p
Memoria del Taller de Priorización de Prácticas de Tecnologías de Agricultura Sostenible Adaptadas al Clima (ASAC) en El Salvador
El Programa de Investigación de CGIAR en Cambio Climático, Agricultura y Seguridad Alimentaria (CCAFS), liderado por el Centro Internacional de Agricultura Tropical, bajo el marco del proyecto FIDA “Un viaje en común” en conjunto con el Ministerio de Agricultura y Ganadería (MAG) desarrolló el 1er taller de priorización de prácticas y tecnologías de Agricultura Sostenible Adaptada al Clima (ASAC) en la ciudad de San Salvador, El Salvador, con el propósito de reforzar acciones y alianzas a nivel institucional y gubernamental y lograr incidir en la formulación e implementación de políticas para lograr dicha transformación del sistema alimentario convencional, así como generar información clave para promover oportunidades de inversión para la adaptación al cambio climático en el Corredor Seco del país.The CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS), led by the International Center for Tropical Agriculture, under the framework of the IFAD project “A common journey” in conjunction with the Ministry of Agriculture and Livestock (MAG ) developed the first workshop on prioritization of climate-smart agriculture (CSA) practices and technologies in the city of San Salvador, El Salvador, with the purpose of strengthening actions and alliances at the institutional and governmental level and influencing the formulation and implementation of policies to achieve such transformation of the conventional food system, as well as generate key information to promote investment opportunities for adaptation to climate change in the country's Dry Corridor
Memoria del Taller de Priorización de Prácticas de Tecnologías de Agricultura Sostenible Adaptadas al Clima (ASAC) en Honduras
El Programa de Investigación de CGIAR en Cambio Climático, Agricultura y Seguridad Alimentaria (CCAFS), liderado por el Centro Internacional de Agricultura Tropical, bajo el marco del proyecto FIDA “Un viaje en común” en conjunto con la Secretaría de Agricultura y Ganadería (SAG) de Honduras, desarrollo el 1er taller de priorización de prácticas y tecnologías de Agricultura Sostenible Adaptada al Clima (ASAC) en la ciudad de Tegucigalpa, Honduras, con el propósito de reforzar acciones y alianzas a nivel institucional y gubernamental y lograr incidir en la formulación e implementación de políticas para lograr dicha transformación del sistema alimentario convencional, así como generar información clave para promover oportunidades de inversión para la adaptación al cambio climático en el Corredor Seco del país.The CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS), led by the International Center for Tropical Agriculture, under the framework of the IFAD project "A common journey" in conjunction with the Ministry of Agriculture and Livestock (SAG) of Honduras, developed the 1st workshop of prioritization of practices and technologies of Climate-Smart Agriculture (CSA) in the city of Tegucigalpa, Honduras, with the purpose of strengthening actions and alliances at the institutional and governmental level and to influence the formulation and implementation of policies to achieve such transformation of the conventional food system, as well as generating key information to promote investment opportunities for climate change adaptation in the country's Dry Corridor
Intervenciones de enfermería durante la atención prenatal de bajo riesgo en el sector número 1 del Policlínico Trinidad Guevara Narváez del municipio de Matagalpa segundo semestre 2016
Después de desarrollar este tema, la problemática sobre las intervenciones de enfermería en la atención prenatal se llegó a la conclusión que existe todavía mucha dificultad para la elaboración de un control prenatal con calidad y calidez.
El control prenatal es un conjunto de acciones y procedimientos muy importantes destinados a la prevención de la morbimortalidad materna y perinatal, así como la preparación de la madre para el parto y cuido del recién nacido.
También sirve para detectar y manejar adecuadamente factores de riesgos y problemas que resulten durante el embarazo, parto y puerperio.
El propósito de nuestra investigación fue relacionar las intervenciones de enfermería según la norma y la aplicación de esta durante la atención prenatal en el centro de salud Trinidad Guevara Narváez de Matagalpa durante el segundo semestre del año 2016. Una vez por semana desde agosto hasta noviembre del 2016 se visitó el sector 1 de este centro de salud para observar la calidad de la atención prenatal en mujeres con embarazos de bajo riesgo.
Se observó que en la mayoría de los controles prenatales se realizaron de acuerdo a las normativas Minsa, pero también existen muchas dificultades en el cumplimiento del 100% de dichas normativas protocolos de atención, debido a diferentes factores, tanto como tiempo lugar de la entrevista, recursos necesarios y disposición del personal de enfermería y paciente. Por lo que es de suma importancia que el personal de enfermería se involucre más en la docencia para una atención de calida
Throttling positive semidefinite zero forcing propagation time on graphs
Zero forcing is a process on a graph that colors vertices blue by starting
with some of the vertices blue and applying a color change rule. Throttling
minimizes the sum of the size of the initial blue vertex set and the number of
the time steps needed to color the graph. We study throttling for positive
semidefinite zero forcing. We establish a tight lower bound on the positive
semidefinite throttling number as a function of the order, maximum degree, and
positive semidefinite zero forcing number of the graph, and determine the
positive semidefinite throttling numbers of paths, cycles, and full binary
trees. We characterize the graphs that have extreme positive semidefinite
throttling numbers.Comment: 20 pages, 7 figures, in press, Discrete Appl. Mat
A Flipped SO(10) GUT Model and the Fermion Mass Hierarchy
We present a viable flipped version of the SO(10) model consistent with the
phenomenological requirements of having a non-trivial quark mixing matrix,
natural doublet-triplet splitting, and a single pair of light electroweak Higgs
doublet scalar bosons. In the presence of suitable non-renormalizable
superpotential terms the model can reproduce the hierarchy observed in quark
masses and mixings as well as an acceptable neutrino mass generated via the
seesaw mechanism needed to explain dark matter and solar neutrino data.Comment: tex file, 20 page
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