Impacts potentiels d’un changement climatique sur le pergélisol dans le nord canadien

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Les relations mères-enfants lorsqu'un enfant enfreint une règle : étude de l'impact des stratégies visant à renforcer les règles et du climat interpersonnel

La documentation sur les pratiques parentales suggère qu’afin de favoriser le développement optimal des enfants, les parents devraient utiliser des pratiques qui sont structurantes et qui soutiennent leur autonomie (Grolnick & Pomerantz, 2009). Dans certaines situations, par exemple lorsqu’un enfant enfreint une règle, il peut toutefois sembler difficile pour les parents d’adopter des stratégies parentales qui allient ces deux dimensions. Qui plus est, peu d’études se sont penchées sur la façon dont les parents peuvent renforcer la structure tout en tenant simultanément compte des besoins et de l’individualité des enfants. L’objectif de cette thèse est d’évaluer l’impact de trois stratégies visant à renforcer les règles (répéter la règle, donner une punition ou avoir recours à une conséquence logique) variant quant à leurs niveaux de structure et de soutien à l’autonomie, et de vérifier leurs effets lorsqu’elles sont employées au sein d’un climat interpersonnel soutenant l’autonomie ou d’un climat interpersonnel contrôlant. Le premier article s’intéresse à l’impact conjoint des stratégies visant à renforcer les règles et du climat interpersonnel sur des indicateurs de conformité et d’intériorisation rapportés par 221 enfants et leurs mères. Les résultats montrent que les mères considèrent les conséquences logiques utilisées dans un climat qui soutient l’autonomie comme étant les pratiques les plus efficaces et les plus acceptables (effet interactif). Les enfants pensent aussi qu’un climat interpersonnel qui soutient l’autonomie est plus efficace et plus acceptable qu’un climat interpersonnel contrôlant. De plus, les résultats suggèrent que les enfants considèrent les conséquences logiques comme des pratiques aussi efficaces, mais plus acceptables que les punitions. Le fait de répéter la règle est jugé comme étant acceptable, mais peu efficace comparativement aux autres stratégies. Pour les enfants, les résultats montrent qu’il n’y a pas d’interaction entre les stratégies visant à renforcer les règles et le climat interpersonnel. Le second article vise à documenter les réactions émotionnelles potentielles des mêmes enfants (N = 221) face aux trois stratégies visant à renforcer les règles et aux climats interpersonnels. Quatre émotions déterminantes dans le processus d’intériorisation sont étudiées, soit la colère, la tristesse, la culpabilité et la honte. Les résultats montrent d’abord qu’un climat interpersonnel contrôlant amènerait les enfants à vivre plus de colère, de tristesse et de honte qu’un climat soutenant l’autonomie. Par contre, les enfants rapportent autant de culpabilité au sein des deux climats interpersonnels. Les résultats suggèrent également que les punitions susciteraient plus de tristesse, de culpabilité et de colère que les conséquences logiques, que les conséquences logiques feraient vivre aux enfants plus de tristesse et de culpabilité que répéter la règle et que les punitions amèneraient les enfants à vivre davantage de honte que répéter la règle. Finalement, les résultats suggèrent que les effets des stratégies visant à renforcer les règles et du climat interpersonnel sont additifs; il n’y a pas d’interaction entre ces deux facteurs. Les contributions théoriques de cette thèse à la documentation sur les pratiques parentales et le développement des enfants, de même que ses implications pratiques pour les parents dans la socialisation des enfants sont discutées.

Heat stress response for physiological traits in dairy and dual purpose cattle populations on phenotypic and genetic scales

The main objective of this thesis was to determine the potential impact of heat stress (HS) on physiological traits of lactating cows and semen quality of bulls kept in a temperate climate. The thesis is comprised of three studies. An innovative statistical modeling aspect common to all three studies was the application of random regression methodology (RRM) to study the phenotypic and genetic trajectory of traits in dependency of a continuous temperature humidity index (THI). In the first study, semen quality and quantity traits of 562 Holstein sires kept on an AI station in northwestern Germany were analyzed in the course of THI calculated from data obtained from the nearest weather station. Heat stress was identified based on a decline in semen quality and quantity parameters. The identified general HS threshold (THI = 60) and the thermoneutal zone (THI in the range from 50 to 60) for semen production were lower than detected in studies conducted in tropical and subtropical climates. Even though adult bulls were characterized by higher semen productivity compared to younger bulls, they responded with a stronger semen production loss during harsh environments. Heritabilities (low to moderate range) and additive genetic variances of semen characteristics varied with different levels of THI. Also, based on genetic correlations genotype, by environment interactions were detected. Taken together, these findings suggest the application of specific selection strategies for specific climate conditions. In the second study, the effect of the continuous environmental descriptor THI as measured inside the barns on rectal temperatures (RT), skin temperatures (ST), vaginal temperatures (VT), respiration rates (RR), and pulse rate (PR) of lactating Holstein Friesian (HF) and dual-purpose German black pied cattle (DSN) was analyzed. Increasing HS from THI 65 (threshold) to THI 86 (maximal THI) resulted in an increase of RT by 0.6 °C (DSN) and 1 °C (HF), ST by 3.5 °C (HF) and 8 °C (DSN), VT by 0.3 °C (DSN), and RR by 47 breaths / minute (DSN), and decreased PR by 7 beats / minute (DSN). The undesired effects of rising THI on physiological traits were most pronounced for cows with high levels of milk yield and milk constituents, cows in early days in milk and later parities, and during summer seasons in the year 2014. In the third study of this dissertation, the genetic components of the cow’s physiological responses to HS were investigated. Heat stress was deduced from indoor THI measurements, and physiological traits were recorded on native DSN cows and their genetically upgraded crosses with Holstein Friesian sires in two experimental herds from pasture-based production systems reflecting a harsh environment of the northern part of Germany. Although heritabilities were in a low range (from 0.018 to 0.072), alterations of heritabilities, repeatabilities, and genetic components in the course of THI justify the implementation of genetic evaluations including heat stress components. However, low repeatabilities indicate the necessity of using repeated records for measuring physiological traits in German cattle. Moderate EBV correlations between different trait combinations indicate the potential of selection for one trait to simultaneously improve the other physiological attributes. In conclusion, bulls of AI centers and lactating cows suffer from HS during more extreme weather conditions also in the temperate climate of Northern Germany. Monitoring physiological traits during warm and humid conditions could provide precious information for detection of appropriate times for implementation of cooling systems and changes in feeding and management strategies. Subsequently, the inclusion of these physiological traits with THI specific breeding values into overall breeding goals could contribute to improving cattle adaptability by selecting the optimal animal for extreme hot and humid conditions. Furthermore, the recording of meteorological data in close distance to the cow and visualizing the surface body temperature by infrared thermography techniques might be helpful for recognizing heat tolerance and adaptability in cattle.

Relación entre los estilos de liderazgo y los niveles de resiliencia de los subordinados

El presente documento hace un análisis de la influencia que ejercen los diferentes tipos de liderazgo, carismático y transaccional, de un directivo de una organización sobre los subordinados de la misma, que a su vez afecta positiva o negativamente el nivel de resiliencia de los mismos. De la misma forma, se ha identificado la relación que existe entre el nivel de resiliencia de los subordinados de una organización y el cumplimiento de objetivos corporativos de la misma. Todo lo anterior se justifica en la economía globalizada de la que ahora hacemos parte que obliga a las empresas a generar nuevas estrategias de competitividad dentro de ambientes turbulentos y cambiantes donde, el desarrollar y motivar el recurso humano de la organización toma importancia para la ejecución exitosa de estrategias diferenciales.

Percepción de los trabajadores acerca del sistema de seguridad y salud en el trabajo en un hospital de III nivel, Bogotá-Colombia. 2014.

Objetivo: Evaluar la percepción que tienen los trabajadores acerca del sistema de seguridad y salud en el trabajo en la población asistencial y administrativa en un Hospital de III nivel de atención., Bogotá-Colombia. Materiales y métodos: Estudio de corte transversal en población de trabajadores asistenciales y administrativos. Se aplicó el “Cuestionario Nórdico Sobre Seguridad en el Trabajo NOSACQ 50 Spanish” validado. La muestra fue probabilística estratificada aleatoria, en 308 trabajadores (230 asistenciales y 78 administrativos). Resultados: El promedio de edad fue 39.5± 12 años, con mayor frecuencia de género femenino (74.68%), estado civil soltero (38.96%) y nivel educativo técnico (34.40%). La percepción que tienen los trabajadores acerca del sistema de seguridad y salud en el trabajo fue independiente de su tipo de actividad laboral administrativa y asistencial (p>0.05), la mayor percepción en ambos grupos fue la confianza de los trabajadores en la eficacia del sistema de seguridad (2.71 y 2.77), y las de menor percepción presentaron el empoderamiento de seguridad de gestión (2.35 y 2.46) y la seguridad como prioridad de los empleados y rechazo del riesgo (2.35 y 2.40). Conclusiones: Los trabajadores del Hospital tienen un nivel adecuado de buena percepción acerca de los aspectos de seguridad y salud en el trabajo donde se evidenció que la fortaleza es la confianza de los trabajadores en la eficacia del sistema y la debilidad del sistema se encuentra en la falta de empoderamiento y rechazo al riesgo.

Caracterización de la cultura organizacional y lineamientos de intervención para la implementación de procesos de cambio en las organizaciones. Caso empresa sector financiero

El presente Trabajo de Grado busca caracterizar la cultura organizacional de una empresa del sector Financiero en Colombia y realizar orientaciones de acciones para el cambio organizacional de acuerdo con la estrategia de perdurabilidad establecida por la Alta Dirección de dicha empresa. Para este fin, se realiza una cuidadosa revisión y actualización del estado del arte de los conceptos clave ¨Cultura Organizacional¨ y ¨Cambio Organizacional¨. Es de resaltar que para el primero de ellos, se toma como punto de partida el estado del arte sobre Cultura Organizacional realizado por el profesor Carlos Eduardo Méndez Álvarez y cuyo marco temporal abarca desde los orígenes del concepto en el siglo XIX hasta el año 2006. Asimismo, luego de una cuidadosa revisión de los Modelos de Cambio Organizacional existentes y de la realidad de la empresa objeto de estudio, se adopta el Modelo ADKAR que consta de cinco fases: Conciencia del Cambio, Deseo, Conocimiento, Capacidad – Habilidad y Refuerzo. Asimismo, a partir de la construcción de un fundamento teórico sólido y a través de la aplicación de la metodología para describir la Cultura Organizacional en Colombia MEDECO se busca una aproximación a la Cultura Organizacional de la empresa objeto de estudio con el fin de describir e identificar los rasgos predominantes de su cultura organizacional y entregar una propuesta final con los rasgos necesarios que alientan la consecución exitosa de los procesos de cambio.

Liderazgo y Clima Organizacional en un Colegio de Cundinamarca. Lineamientos Básicos para su Intervención

El propósito de este estudio fue describir y analizar el liderazgo de los directivos y el clima organizacional presentes en un Colegio de Cundinamarca y con base en ello, plantear algunos lineamientos para su intervención. Para tal fin se desarrolló un estudio descriptivo, donde el liderazgo y el clima organizacional se midieron a través de dos instrumentos: el Test de Adjetivos de Pitcher (PAT) (Pitcher, 1997) y la Escala del Clima Organizacional (ECO) (Fernándes, 2008), respectivamente. La aplicación de estos instrumentos se realizó de forma colectiva, para lo cual se trabajó con los directivos, los docentes y los estudiantes de los grados noveno, décimo y undécimo del Colegio, que constituyeron el grupo estudiado. Para el caso de los educandos, los test se aplicaron con previo consentimiento de los padres. De acuerdo con los resultados, el Colegio estudiado denota ciertas dificultades respecto al liderazgo y algunos problemas de Clima Organizacional que deben ser intervenidos de manera prioritaria. La comunidad educativa estudiada registra una inconformidad mayoritaria en la forma en que se ejerce el liderazgo, bien sea por ausencia del mismo, o por ejercerse de formas no deseadas a la luz de las teorías y de la práctica.

Relation between temperature and mortality in thirteen Spanish cities

In this study we examined the shape of the association between temperature and mortality in 13 Spanish cities representing a wide range of climatic and socio demographic conditions. The temperature value linked with minimum mortality (MMT) and the slopes before and after the turning point (MMT) were calculated. Most cities showed a V-shaped temperature-mortality relationship. MMTs were generally higher in cities with warmer climates. Cold and heat effects also depended on climate: effects were greater in hotter cities but lesser in cities with higher variability. The effect of heat was greater than the effect of cold. The effect of cold and MMT was, in general, greater for cardio-respiratory mortality than for total mortality, while the effect of heat was, in general, greater among the elderly

Perceção dos alunos e professores de Educação Física, relativamente ao clima motivacional

Os professores durante as aulas, através das suas formas de interação e de comunicação, promovem climas motivacionais que poderão envolver mais uma orientação para a tarefa, onde existe uma preocupação com a aprendizagem, com o progresso e a cooperação com os colegas ou um clima motivacional orientado para o ego, onde os alunos tentam comparar os resultados alcançados, o reconhecimento desigual e superar os pares. Os professores têm um entendimento do clima motivacional proporcionado durante aulas e os alunos têm uma perceção dos climas motivacionais empreendidos pelos professores. O objetivo geral deste estudo foi verificar se a perceção do clima motivacional que os professores têm das suas aulas, será análoga à dos alunos. A amostra foi organizada pelas quatro escolas do ensino básico do 2º e 3º ciclo, com 18 professores e 865 alunos pertencentes ao concelho de Silves. Os resultados apontam que os professores e os alunos têm a mesma orientação para a perceção do clima motivacional. Os professores na perceção para a tarefa apresentam valores superiores à dos alunos e na perceção para o ego os alunos têm valores superiores à dos professores. Existem diferenças significativas nas variáveis escola, ano de escolaridade e género.

The biometeorology of high-altitude insect layers.

Flight at high altitude is part of a migration strategy that maximises insect population displacement. This thesis represents the first substantial analysis of insect migration and layering in Europe. Vertical-looking entomological radar has revealed specific characteristics of high-altitude flight: in particular layering (where a large proportion of the migrating insects are concentrated in a narrow altitude band). The meteorological mechanisms underpinning the formation of these layers are the focus of this thesis. Aerial netting samples and radar data revealed four distinct periods of high-altitude insect migration: dawn, daytime, dusk, and night-time. The most frequently observed nocturnal profiles during the summertime were layers. It is hypothesised that nocturnal layers initiate at a critical altitude (200–500 m above ground level) and time (20:00–22:00 hours UTC). Case study analysis, statistical analysis, and a Lagrangian trajectory model showed that nocturnal insect layers probably result from the insects’ response to meteorological conditions. Temperature was the variable most correlated with nocturnal insect layer presence and intensity because insects are poikilothermic, and temperatures experienced during high-altitude migration in temperate climates are expected to be marginal for many insects’ flight. Hierarchical effects were detected such that other variables—specifically wind speed—were only correlated with insect layer presence and intensity once temperatures were warm. The trajectory model developed comprised: (i) insect flight characteristics; (ii) turbulent winds (which cause vertical spread of the layer); and (iii) mean wind speed, which normally leads to horizontal displacements of hundreds of kilometres in a single migratory flight. This thesis has revealed that there is considerable migratory activity over the UK in the summer months, and a range of fascinating phenomena can be observed (including layers). The UK has moved from one of the least studied to perhaps the best studied environments of aerial insect migration and layering in the world.

Crop yield reduction in the tropics under climate change: Processes and uncertainties

Many modelling studies examine the impacts of climate change on crop yield, but few explore either the underlying bio-physical processes, or the uncertainty inherent in the parameterisation of crop growth and development. We used a perturbed-parameter crop modelling method together with a regional climate model (PRECIS) driven by the 2071-2100 SRES A2 emissions scenario in order to examine processes and uncertainties in yield simulation. Crop simulations used the groundnut (i.e. peanut; Arachis hypogaea L.) version of the General Large-Area Model for annual crops (GLAM). Two sets of GLAM simulations were carried out: control simulations and fixed-duration simulations, where the impact of mean temperature on crop development rate was removed. Model results were compared to sensitivity tests using two other crop models of differing levels of complexity: CROPGRO, and the groundnut model of Hammer et al. [Hammer, G.L., Sinclair, T.R., Boote, K.J., Wright, G.C., Meinke, H., and Bell, M.J., 1995, A peanut simulation model: I. Model development and testing. Agron. J. 87, 1085-1093]. GLAM simulations were particularly sensitive to two processes. First, elevated vapour pressure deficit (VPD) consistently reduced yield. The same result was seen in some simulations using both other crop models. Second, GLAM crop duration was longer, and yield greater, when the optimal temperature for the rate of development was exceeded. Yield increases were also seen in one other crop model. Overall, the models differed in their response to super-optimal temperatures, and that difference increased with mean temperature; percentage changes in yield between current and future climates were as diverse as -50% and over +30% for the same input data. The first process has been observed in many crop experiments, whilst the second has not. Thus, we conclude that there is a need for: (i) more process-based modelling studies of the impact of VPD on assimilation, and (ii) more experimental studies at super-optimal temperatures. Using the GLAM results, central values and uncertainty ranges were projected for mean 2071-2100 crop yields in India. In the fixed-duration simulations, ensemble mean yields mostly rose by 10-30%. The full ensemble range was greater than this mean change (20-60% over most of India). In the control simulations, yield stimulation by elevated CO2 was more than offset by other processes-principally accelerated crop development rates at elevated, but sub-optimal, mean temperatures. Hence, the quantification of uncertainty can facilitate relatively robust indications of the likely sign of crop yield changes in future climates. (C) 2007 Elsevier B.V. All rights reserved.

Examining the interaction of growing crops with local climate using a coupled crop-climate model

This paper examines to what extent crops and their environment should be viewed as a coupled system. Crop impact assessments currently use climate model output offline to drive process-based crop models. However, in regions where local climate is sensitive to land surface conditions more consistent assessments may be produced with the crop model embedded within the land surface scheme of the climate model. Using a recently developed coupled crop–climate model, the sensitivity of local climate, in particular climate variability, to climatically forced variations in crop growth throughout the tropics is examined by comparing climates simulated with dynamic and prescribed seasonal growth of croplands. Interannual variations in land surface properties associated with variations in crop growth and development were found to have significant impacts on near-surface fluxes and climate; for example, growing season temperature variability was increased by up to 40% by the inclusion of dynamic crops. The impact was greatest in dry years where the response of crop growth to soil moisture deficits enhanced the associated warming via a reduction in evaporation. Parts of the Sahel, India, Brazil, and southern Africa were identified where local climate variability is sensitive to variations in crop growth, and where crop yield is sensitive to variations in surface temperature. Therefore, offline seasonal forecasting methodologies in these regions may underestimate crop yield variability. The inclusion of dynamic crops also altered the mean climate of the humid tropics, highlighting the importance of including dynamical vegetation within climate models.

Modelling European winter wind storm losses in current and future climate

Severe wind storms are one of the major natural hazards in the extratropics and inflict substantial economic damages and even casualties. Insured storm-related losses depend on (i) the frequency, nature and dynamics of storms, (ii) the vulnerability of the values at risk, (iii) the geographical distribution of these values, and (iv) the particular conditions of the risk transfer. It is thus of great importance to assess the impact of climate change on future storm losses. To this end, the current study employs—to our knowledge for the first time—a coupled approach, using output from high-resolution regional climate model scenarios for the European sector to drive an operational insurance loss model. An ensemble of coupled climate-damage scenarios is used to provide an estimate of the inherent uncertainties. Output of two state-of-the-art global climate models (HadAM3, ECHAM5) is used for present (1961–1990) and future climates (2071–2100, SRES A2 scenario). These serve as boundary data for two nested regional climate models with a sophisticated gust parametrizations (CLM, CHRM). For validation and calibration purposes, an additional simulation is undertaken with the CHRM driven by the ERA40 reanalysis. The operational insurance model (Swiss Re) uses a European-wide damage function, an average vulnerability curve for all risk types, and contains the actual value distribution of a complete European market portfolio. The coupling between climate and damage models is based on daily maxima of 10 m gust winds, and the strategy adopted consists of three main steps: (i) development and application of a pragmatic selection criterion to retrieve significant storm events, (ii) generation of a probabilistic event set using a Monte-Carlo approach in the hazard module of the insurance model, and (iii) calibration of the simulated annual expected losses with a historic loss data base. The climate models considered agree regarding an increase in the intensity of extreme storms in a band across central Europe (stretching from southern UK and northern France to Denmark, northern Germany into eastern Europe). This effect increases with event strength, and rare storms show the largest climate change sensitivity, but are also beset with the largest uncertainties. Wind gusts decrease over northern Scandinavia and Southern Europe. Highest intra-ensemble variability is simulated for Ireland, the UK, the Mediterranean, and parts of Eastern Europe. The resulting changes on European-wide losses over the 110-year period are positive for all layers and all model runs considered and amount to 44% (annual expected loss), 23% (10 years loss), 50% (30 years loss), and 104% (100 years loss). There is a disproportionate increase in losses for rare high-impact events. The changes result from increases in both severity and frequency of wind gusts. Considerable geographical variability of the expected losses exists, with Denmark and Germany experiencing the largest loss increases (116% and 114%, respectively). All countries considered except for Ireland (−22%) experience some loss increases. Some ramifications of these results for the socio-economic sector are discussed, and future avenues for research are highlighted. The technique introduced in this study and its application to realistic market portfolios offer exciting prospects for future research on the impact of climate change that is relevant for policy makers, scientists and economists.

Assessing nitrogen dynamics in European ecosystems, integrating measurement and modelling: conclusions

This contribution closes this special issue of Hydrology and Earth System Sciences concerning the assessment of nitrogen dynamics in catchments across Europe within a semi-distributed Integrated Nitrogen model for multiple source assessment in Catchments (INCA). New developments in the understanding of the factors and processes determining the concentrations and loads of nitrogen are outlined. The ability of the INCA model to simulate the hydrological and nitrogen dynamics of different European ecosystems is assessed and the results of the first scenario analyses investigating the impacts of deposition, climatic and land-use change on the nitrogen dynamics are summarised. Consideration is given as to how well the model has performed as a generic too] for describing the nitrogen dynamics of European ecosystems across Arctic, Maritime. Continental and Mediterranean climates, its role in new research initiatives and future research requirements.

Evaluating the century C model using long-term fertilizer trials in the Indo-Gangetic Plains, India

The GEFSOC Project developed a system for estimating soil carbon (C) stocks and changes at the national and sub-national scale. As part of the development of the system, the Century ecosystem model was evaluated for its ability to simulate soil organic C (SOC) changes in environmental conditions in the Indo-Gangetic Plains, India (IGP). Two long-term fertilizer trials (LTFT), with all necessary parameters needed to run Century, were used for this purpose: a jute (Corchorus capsularis L.), rice (Oryza sativa L.) and wheat (Triticum aestivum L.) trial at Barrackpore, West Bengal, and a rice-wheat trial at Ludhiana, Punjab. The trials represent two contrasting climates of the IGP, viz. semi-arid, dry with mean annual rainfall (MAR) of < 800 mm and humid with > 1600 turn. Both trials involved several different treatments with different organic and inorganic fertilizer inputs. In general, the model tended to overestimate treatment effects by approximately 15%. At the semi-arid site, modelled data simulated actual data reasonably well for all treatments, with the control and chemical N + farm yard manure showing the best agreement (RMSE = 7). At the humid site, Century performed less well. This could have been due to a range of factors including site history. During the study, Century was calibrated to simulate crop yields for the two sites considered using data from across the Indian IGP. However, further adjustments may improve model performance at these sites and others in the IGP. The availability of more longterm experimental data sets (especially those involving flooded lowland rice and triple cropping systems from the IGP) for testing and validation is critical to the application of the model's predictive capabilities for this area of the Indian sub-continent. (C) 2007 Elsevier B.V. All rights reserved.