Search results for "33"
showing 10 items of 1917 documents
Long-term cropping systems and tillage management effects on soil organic carbon stocks and steady state level of C sequestration rates in a semiarid…
2010
A calcareous and clayey xeric Chromic Haploxerept of a long-term experimental site in Sicily (Italy) was sampled (0–15 cm depth) under different land use management and cropping systems (CSs) to study their effect on soil aggregate stability and organic carbon (SOC). The experimental site had three tillage managements (no till [NT], dual-layer [DL] and conventional tillage [CT]) and two CSs (durum wheat monocropping [W] and durum wheat/faba bean rotation [WB]). The annually sequestered SOC with W was 2·75-times higher than with WB. SOC concentrations were also higher. Both NT and CT management systems were the most effective in SOC sequestration whereas with DL system no C was sequestered. …
Depth profiling of Pu, 241Am and 137Cs in soils from southern Belarus measured by ICP-MS and alpha- and gamma-spectrometry
2003
The depth distribution of plutonium, americium, and Cs-137 originating front the 1986 accident at the Chernobyl Nuclear Power Plant (NPP) was investigated in several soil profiles in the vicinity from Belarus. The vertical migration of transuranic elements in soils typical of the 30 km relocation area around Chernobyl NPP was studied using inductively coupled plasma mass spectrometry (ICP-MS), alpha spectrometry, and gamma spectrometry. Transuranic concentrations in upper soil layers ranged from 6 x 10(-12) g g(-1) to 6 x 10(-10) g g(-1) for plutonium and from 1.8 x 10(-13) g g(-1) to 1.6 x 10(-11) g g(-1) for americium. These concentrations correspond to specific activities of Pu239+240 of…
Guardia y custodia compartida impuesta
2018
Cuando una pareja con hijos comunes menores de edad deja de convivir surge la necesidad de determinar las reglas o normas por las que se regirá la nueva situación familiar. Estas normas pueden ser de carácter económico o personal. Entre las personales, y una sobre las que más les cuesta decidir a los progenitores, es la relativa al cuidado de los hijos y a cómo se va a dar continuidad a las relaciones con ellos una vez se haya producido la separación. Lo mejor sería que los propios progenitores pudieran llegar a un acuerdo al respecto ya que ellos son los que mejor conocen a sus hijos y los mejores conocedores de la situación que están viniendo. Pero en defecto de acuerdo será necesario det…
A Methodology for Protection of Trees Against Lightning Strikes as a Measure to Prevent Fires and Loss of Human Life
2021
Some regions may be characterized by a very low annual lightning ground flash density, and yet lightning strikes seem to have been in those areas the cause of widespread wildfires in forested areas. Due to global climate change, these occurrences seem to be an increasing threat. In this paper, the authors discuss the withstand capability of trees against lightning and introduce the criteria for the deployment of tree lightning protection systems (TLPS) to protect forested areas, where deemed necessary by the tree risk assessment. This work analytically identifies the critical trunk radius of the tree below which the tree may explode in the case of a lightning strike and ignite the surroundi…
Evaluación en conductores de la capacidad de atención visual a través del desarrollo de los movimientos oculares
2015
La circulación vial es una realidad social, compleja y dinámica en las sociedades avanzadas, siendo la habilidad para conducir seguro el resultado de la interacción entre el individuo, el coche y el entorno. Dentro del factor humano las condiciones visuales, la capacidad cognitiva, y la habilidad, son determinantes para responder adecuadamente ante la multitarea compleja que implica al entorno cambiante de la conducción. A través de una óptima búsqueda y correcta atención se reconoce, analiza y procesa la información visual, lo cual permite comprender, organizar y actuar ante el espacio visual externo dinámico. Cualquier elemento o factor perturbador de la visión, bien sea por inducir distr…
Musculoskeletal ultrasound in hemophilia: Results and recommendations from a global survey and consensus meeting
2021
Abstract Introduction For persons with hemophilia, optimization of joint outcomes is an important unmet need. The aim of this initiative was to determine use of ultrasound in evaluating arthropathy in persons with hemophilia, and to move toward consensus among hemophilia care providers regarding the preferred ultrasound protocols for global adaptation. Methods A global survey of hemophilia treatment centers was conducted that focused on understanding how and why ultrasound was being used and endeavored to move toward consensus definitions of both point‐of‐care musculoskeletal ultrasound (POC‐MSKUS) and full diagnostic ultrasound, terminology to describe structures being assessed by ultrasou…
La elección de los modelos de costes de calidad: un análisis cualitativo
2001
El actual contexto empresarial promueve que las organizaciones desarrollen una cultura orientada a la mejora de la calidad. En este sentido, consideramos que los distintos modelos de costes de calidad propuestos por la Contabilidad de Gestión pueden realizar importantes aportaciones en el proceso de mejora continua. La tesis pretende mostrar a las organizaciones las características de los distintos modelos de costes de calidad existentes de forma que éstas puedan seleccionarlos en función del mejor ajuste a sus parámetros específicos. Para ello, previamente presentamos un marco de trabajo que aborda como las variables contextuales afectan el Sistema de Información de Contabilidad de Gestión…
Automated scoring of teachers’ pedagogical content knowledge : a comparison between human and machine scoring
2020
To validly assess teachers’ pedagogical content knowledge (PCK), performance-based tasks with open-response formats are required. Automated scoring is considered an appropriate approach to reduce the resource-intensity of human scoring and to achieve more consistent scoring results than human raters. The focus is on the comparability of human and automated scoring of PCK for economics teachers. The answers of (prospective) teachers (N = 852) to six open-response tasks from a standardized and validated test were scored by two trained human raters and the engine “Educational SCoRIng Toolkit” (ESCRITO). The average agreement between human and computer ratings, κw = 0.66, suggests a convergent …
Synthetic Inertia Impact on Inter-Area Oscillations of the Continental Europe Power System
2020
The overall kinetic energy reduction due to increasing share of converter-interfaced generation (CIG) has been investigated so far by several works for systems of different types and sizes. The so called synthetic inertia is one of the most common and reviewed solutions to the issue of system inertia reduction. The paper investigates the effects of synthetic inertia as frequency service provided by the CIG sources for the Continental Europe (CE) synchronous area using a detailed large scale dynamic model. The model - provided in the basic form by the System Protection & Dynamics (SP&D) group of the ENTSOE - is properly developed substituting a determined amount of synchronous machin…
Shared Situational Awareness in a Professional Soccer Team: An Explorative Analysis of Post-Performance Interviews
2020
Sport science research has done little to elaborate on the cognitive factors that turn a collection of individual players into a coordinated elite team. The purpose of this paper is to clarify if the players and coach of an elite soccer team express shared situational awareness. Ten players and one coach were exposed to twelve video pictures from a previous soccer match, and their statements for each picture were recorded and analyzed using a qualitative approach. Two of five game situations were with ball possession and three out of seven were without ball possession