1,056 research outputs found
Special Geometry and Twisted Moduli in Orbifold Theories with Continuous Wilson Lines
Target space duality symmetries, which acts on K\"ahler and continuous Wilson
line moduli, of a () 2-dimensional subspace of the moduli
space of orbifold compactification are modified to include twisted moduli.
These spaces described by the cosets are
K\"ahler, a fact which is exploited in deriving the extension of tree
level duality transformation to include higher orders of the twisted moduli.
Also, restrictions on these higher order terms are derived.Comment: 13 page
Nutrition is Perceived as an Ecosystem Service of the Mangrove by Rural People in Ecuador
The mangrove ecosystem is considered as the source of livelihood, particularly for coastal areas. This study explores the perception of the inhabitants of Puerto El Morro and the island of Costa Rica (Ecuador) against the ecosystem services of the mangrove. Seven quantitative variables were used on the Likert scale by performing exploratory factor analysis. The results were based on a sample of 94 participants finding 2 factors, tourism (29.07% of variance) and nutritious food production (25.45% of variance remaining). The reliability of the questionnaire was acceptable according to Cronbach’s Alpha 0.654. A confirmatory factor analysis is necessary to revalidate the items of the factors.
Keywords: coastal communities, eating, mangroves, livelihoods, nutrition.
Resumen
El ecosistema de manglar se considera fuente de medios de vida, en particular para zonas costeras. Este estudio explora la percepción de los habitantes de Puerto El Morro y la isla Costa Rica (Ecuador) frente a los servicios ecosistémicos del manglar. Se utilizaron 7 variables cuantitativas en escala de Likert realizando análisis factorial exploratorio. Los resultados parten de una muestra de 94 participantes, hallando 2 factores: turismo (29,07% de varianza) y producción alimentos nutritivos (25,45% de varianza restante). La confiabilidad del cuestionario fue aceptable según el Alfa de Cronbach 0.654. Es necesario un análisis factorial confirmatorio para revalidar los Ãtems de los factores.
Palabras Clave: comunidades costeras; alimentación; manglares; medios de vida; nutrición
Clothoid-Based Three-Dimensional Curve for Attitude Planning
Interest in flying robots, also known as unmanned aerial vehicles (UAVs), has grown during last years in both military and civil fields [1, 2]. The same happens to autonomous underwater vehicles (AUVs) [3]. These vehicles, UAVs and AUVs, offer a wide variety of possible applications and challenges, such as control, guidance or navigation [2, 3]. In this sense, heading and attitude control in UAVs is very important [4], particularly relevant in airplanes (fixed-wing flying vehicles), because they are strongly non-linear, coupled, and tend to be underactuated systems with non-holonomic constraints. Hence, designing a good attitude controller is a difficult task [5, 6, 7, 8, 9], where stability must be taken into account by the controller [10]. Indeed, if the reference is too demanding for the controller or non-achievable because its dynamics is too fast, the vehicle might become unstable. In order to address this issue, autonomous navigation systems usually include a high-level path planner to generate smooth reference trajectories to be followed by the vehicle using a low-level controller. Usually a set of waypoints is given in GPS coordinates, normally from a map, in order to apply a smooth point-to-point control trajectory [11, 12]
Sistema computacional de integración del método de despliegue de la función de calidad y de la lógica difusa
Este artÃculo presenta un programa computacional que integra el método de despliegue de la función de calidad con la teorÃa de conjuntos difusos. El programa permite estimar los niveles de impacto que las caracterÃsticas de ingenierÃa de un producto pueden tener sobre la satisfacción del usuario. La teorÃa de conjuntos difusos se usa para tener en cuenta la incertidumbre de la información. Los grados de importancia de los atributos del usuario y las relaciones entre éstos y las caracterÃsticas de ingenierÃa se representan mediante números difusos triangulares. Se utiliza el nuevo promedio difuso ponderado para evitar que la imprecisión de los resultados sea innecesariamente alta. Se presenta un ejemplo de aplicación para ilustrar el uso del software
Neutrino-less Double Beta Decay and Particle Physics
We review the particle physics aspects of neutrino-less double beta decay.
This process can be mediated by light massive Majorana neutrinos (standard
interpretation) or by something else (non-standard interpretations). The
physics potential of both interpretations is summarized and the consequences of
future measurements or improved limits on the half-life of neutrino-less double
beta decay are discussed. We try to cover all proposed alternative realizations
of the decay, including light sterile neutrinos, supersymmetric or left-right
symmetric theories, Majorons, and other exotic possibilities. Ways to
distinguish the mechanisms from one another are discussed. Experimental and
nuclear physics aspects are also briefly touched, alternative processes to
double beta decay are discussed, and an extensive list of references is
provided.Comment: 96 pages, 38 figures. Published versio
Biofilm-inhibiting effect and anti-infective activity of N,C-linked aryl isoquinolines and the use thereof
Anti-infective and biofilm-inhibiting activities of aryl isoquinoline-derivatives of the general formulae 1 to 3
Figure US08173673-20120508-C00001
are described
Aspirin for evidence-based preeclampsia prevention trial: effect of aspirin in prevention of preterm preeclampsia in subgroups of women according to their characteristics and medical and obstetrical history.
Objective: To examine whether there are differences in the effect of aspirin on the incidence of preterm-PE in the ASPRE trial in subgroups defined according to maternal characteristics and medical and obstetrical history.
Study design: This was a secondary analysis of data from the ASPRE trial. In ASPRE women with singleton pregnancies had screening by means of an algorithm that combines maternal factors and biomarkers at 11-13 weeks’ gestation. Those with an estimated risk for preterm-PE of >1 in 100 were invited to
participate in a double-blind trial of aspirin (150 mg/day) vs. placebo from 11 to 14 until 36 weeks’ gestation. Aspirin was associated with a significant reduction in the incidence of preterm-PE with delivery at 90% of the prescribed medication. Results are presented as forest plot with P values for the
interaction effects, group sizes, event counts and estimated odds ratios. We examined whether the test of interaction was significant at the 5% level with a Bonferroni adjustment for multiple comparisons.
Results: There was no evidence of heterogeneity in the aspirin effect in subgroups defined according to maternal characteristics and obstetrical history. In participants with chronic hypertension preterm-PE occurred in 10.2% (5/49) in the aspirin group and in 8.2% (5/61) in the placebo group (adjusted odds ratio 1.29, 95% confidence interval, 0.33 to 5.12); the respective values in those without chronic hypertension were 1.1% (8/749) in the aspirin group and 3.9% (30/761) in the placebo group (adjusted odds ratio 0.27, 95% confidence interval, 0.12 to 0.60). In all participants with adherence of >90% the adjusted odds ratio in the aspirin group was 0.24 (95% CI 0.09 to 0.65), in the subgroup with chronic hypertension it was 2.06 (95% CI 0.40 to 10.71) and in those without chronic hypertension it was 0.05 (95% CI 0.01 to 0.41). For the complete data set the test of interaction was not significant at the 5% level (p=0.055), but in those with adherence >90%, after adjustment for multiple comparisons, the interaction was significant at the 5% level (p=0.0019).
Conclusions: The beneficial effect of aspirin in the prevention of preterm preeclampsia may not apply in pregnancies with chronic hypertension. There was no evidence of heterogeneity in the aspirin effect in subgroups defined according to maternal characteristics and obstetrical history
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