La « biotransformation ruminale » est un concept qui regroupe l'ensemble des réactions se produisant dans le rumen (dégradation, synthèse et conversion). Ces réactions sont pilotées par trois forces motrices majeures : les lois de la cinétique chimique, de la thermodynamique et de la dynamique des populations microbiennes. Cette thèse a pour objectif d'étudier l'impact d'un facteur alimentaire (pourcentage de concentrés incorporés dans la ration, supplémentation en huile) sur le fonctionnement du rumen et la biotransformation ruminale des constituants alimentaires en termes de dynamique et d'intensité. Cette thèse a combiné trois types d'approches : un essai in vivo sur des chèvres en milieu de lactation, deux essais in vitro (méthode du gaz-test) et une approche de modélisation mécaniste. In vivo, les réactions de biotransformation ont été évaluées par un suivi de la dynamique postprandiale et des mesures de bilans duodénaux. De plus, nous avons étudié l'influence réciproque des phénomènes ruminaux et de l'animal-hôte (comportement d'ingestion, métabolisme, paramètres zootechniques, et qualité du lait) sur le long terme (6 semaines). Nos résultats sont en accord avec la plupart des études antérieures effectuées chez la chèvre ou la vache laitières. Les modifications du comportement d'ingestion observées après 6 semaines avec le régime riche en concentrés ont eu un effet sur les phénomènes digestifs ruminaux. Les flux duodénaux d'acides gras ont expliqué les profils en acides gras du lait. Les études in vitro ont donné des résultats très cohérents par rapport à l'in vivo lorsque les animaux donneurs recevaient les régimes incubés. Enfin, nous avons développé un modèle mécaniste de fonctionnement de rumen in vitro décrivant de manière spécifique les lois physico-chimiques expliquant les dynamiques d'évolution du pH et de formation de gaz. Ce modèle aboutit à des résultats satisfaisants et pourrait être intégré à un modèle de rumen plus complet. La modélisation semble être le meilleur moyen pour intégrer toutes les réactions de biotransformation observées lors d'expérimentations. / “Ruminal biotransformation” is a concept aggregating all the reactions occurring in the rumen (degradation, synthesis and conversion). These reactions are driven by three major driving forces: laws of chemical kinetics, thermodynamics and the dynamics of microbial populations. The principal objective of the thesis was to study how a dietary factor (percentage of concentrate in the ration, oil supplementation) can modify rumen function and the ruminal biotransformation of dietary components in terms of pattern and extent. To answer to this question, three approaches were used: an in vivo experiment on mid-lactation goats, two in vitro experiments (with the gas-test method) and the development of a mechanistic model. In vivo biotransformation reactions were assessed by post-feeding measurements or by duodenal flow determination. Further, the relationships between the rumen and the host animal (intake behaviour, metabolism, performance parameters, and milk quality) were studied over a period of 6 weeks. Our results were consistent with previous reports in goats and dairy cows. Animals adapted their intake behaviour in 6 weeks with the high-concentrate diet. As a consequence, modifications of ruminal digestion patterns were observed. Duodenal flow of fatty acids explained the milk fatty acid profile. The in vitro studies gave consistent results with the in vivo study when donor animals were fed the incubated diets. Finally, a mechanistic model of rumen functioning in in vitro devices was developed. It describes specifically the physicochemical laws explaining pH and gas production patterns. This model gives satisfying results and could be integrated to a larger mechanistic model of rumen. Modelling provides a logical framework within which to mathematically integrate all the biotransformation reactions observed in experiments.

This study try to understand which aspects were fundamental to indoor climate and how to obtain them in order to provide the best possible experience in the thermal comfort of individuals. Thus, arose the studies of Fanger, which was the seed for a new era of discoveries in the area and founded the knowledge our society have today in this globally used standards and norms. Referring to these fundamental aspects of the indoor comfort, data collection was taken in situ to show in details what was happening. This study was executed in order to demonstrate the differences between the data previous and after a process of retrofitting in dwellings built in the 60s and 70s of the century past, in the district of Tjärna Ängar, Borlänge, Sweden. The comparative results using criteria such as Predicted Mean Vote (PMV), Predicted Percentage Dissatisfied (PPD), Draft Rate (DR), air velocity, Mean Radiant Temperature (MRT), Relative Humidity (RH) and air temperature, showed an improvement in 6 of the 8 parameters analyzed. Confirming the expectation that through the retrofitting the residents will be more satisfied, obtain better quality of indoor climate comfort and also increase occupied area in these dwellings.

This study examined different funding methods for financing public education in order to solve the problems associated with large numbers of school districts and great disparities in property wealth without abandonment of property tax as the major revenue source. Using enrollment and State Property Tax Board data for the 1,061 school districts in Texas in 1986-87, four alternative funding plans were studied to compare the equity and fiscal impact of each on public school finance in Texas. The state and local shares of the total cost of education were computed using a combination of three per-pupil expenditure levels and four funding formulas. The per-pupil expenditure levels used were $3,850, $4,200, and $4,580. The formulas used were representative of a full state funding plan, a percentage equalization plan, a power equalization plan, and a foundation school program plan. Since each of the four plans used significantly higher per-pupil expenditure values, all required a greater monetary investment on the part of the state. However, all plans were found to be equalizing in nature if set per-pupil expenditure values were maintained and no local enrichment was permitted. In addition, each of the four plans, as studied, met the fiscal neutrality standard of the 1987 Edqewood v. Kirbv case. The percentage and power equalization plans required less monetary investment on the part of the state than either full state funding or the foundation school program. As a result of the study, it is recommended that the state consider a combination of plans. For example, the state could employ a full state funding model up to the $3,850 per-pupil expenditure level with added permissible local millage being limited and power equalized. In addition, while each of the plans studied reduces inequity, the increased cost of an adequate public school education suggests that the state consider other sources of revenue to fund public education. These could include personal or corporate income taxes.

The content of the thesis consists of a description of constructivist teaching of the topic of percentage in the primary school, that is the teaching in which not the teacher, but the pupil is in the center. The principles of constructivist teaching and the learning process in terms of the theory of generic models are described on the basis of literature. In accordance with these principles, a number of textbooks have been analyzed, in which the the topic of percentage is introduced, and experimental teaching based on the above principles has been prepared. Experimental teaching was realized in two classes of the 7th grade with a different experience with the teaching of mathematics in their 6th grade. The main goal of the work was to prepare, implement, describe and evaluate the teaching of percentage based on pupils' activity and their individual discovery. The lessons have been described and evaluated on the basis of audio recordings, notes from the lessons, records of pupilss solutions, interviews, notes and interviews with a teacher assistant, pre-tests and post-tests. The lessons were analyzed mainly in terms of pupils' involvement in teaching, their discoveries and knowledge acquisition, including its anchoring in the knowledge structure. In both classes, part of the pupils managed to find a...

Tese de mestrado. Engenharia de Segurança e Higiene Ocupacionais. Faculdade de Engenharia. Universidade do Porto. 2011

In den letzten Jahren wurden relativ komplexe Erosionsmodelle entwickelt, deren Teilprozesse immer mehr auf physikalisch begründeten Ansätzen beruhen. Damit verbunden ist eine höhere Anzahl aktueller Eingangsparameter, deren Bestimmung im Feld arbeits- und kostenaufwendig ist. Zudem werden die Parameter punktuell, also an bestimmten Stellen und nicht flächenhaft wie bei der Fernerkundung, erfasst. <br /> <br /> Im Rahmen dieser Arbeit wird gezeigt, wie Satellitendaten als relativ kostengünstige Ergänzung oder Alternative zur konventionellen Parametererhebung genutzt werden können. Dazu werden beispielhaft der Blattflächenindex (LAI) und der Bedeckungsgrad für das physikalisch begründete Erosionsmodell EROSION 3D abgeleitet. Im Mittelpunkt des Interesses steht dabei das Aufzeigen von existierenden Methoden, die die Basis für eine operationelle Bereitstellung solcher Größen nicht nur für Erosions- sondern allgemein für Prozessmodelle darstellen. Als Untersuchungsgebiet dient das primär landwirtschaftlich genutzte Einzugsgebiet des Mehltheuer Baches, das sich im Sächsischen Lößgefilde befindet und für das Simulationsrechnungen mit konventionell erhobenen Eingangsparametern für 29 Niederschlagsereignisse im Jahr 1999 vorliegen [MICHAEL et al. 2000].<br /> <br /> Die Fernerkundungsdatengrundlage bilden Landsat-5-TM-Daten vom 13.03.1999, 30.04.1999 und 19.07.1999. Da die Vegetationsparameter für alle Niederschlagsereignisse vorliegen sollen, werden sie basierend auf der Entwicklung des LAI zeitlich interpoliert. Dazu erfolgt zunächst die Ableitung des LAI für alle vorhandenen Fruchtarten nach den semi-empirischen Modellen von CLEVERS [1986] und BARET & GUYOT [1991] mit aus der Literatur entnommenen Koeffizienten. Des Weiteren wird eine Methode untersucht, nach der die Koeffizienten für das Clevers-Modell aus den TM-Daten und einem vereinfachten Wachstumsmodell bestimmt werden. Der Bedeckungsgrad wird nach ROSS [1981] aus dem LAI ermittelt. Die zeitliche Interpolation des LAI wird durch die schlagbezogene Anpassung eines vereinfachten Wachstumsmodells umgesetzt, das dem hydrologischen Modell SWIM [KRYSANOVA et al. 1999] entstammt und in das durchschnittliche Tagestemperaturen eingehen. Mit den genannten Methoden bleiben abgestorbene Pflanzenteile unberücksichtigt. Im Vergleich zur konventionellen terrestrischen Parametererhebung ermöglichen sie eine differenziertere Abbildung räumlicher Variabilitäten und des zeitlichen Verlaufes der Vegetationsparameter.<br /> <br /> Die Simulationsrechnungen werden sowohl mit den direkten Bedeckungsgraden aus den TM-Daten (pixelbezogen) als auch mit den zeitlich interpolierten Bedeckungsgraden für alle Ereignisse (schlagbezogen) durchgeführt. Bei beiden Vorgehensweisen wird im Vergleich zur bisherigen Abschätzung eine Verbesserung der räumlichen Verteilung der Parameter und somit eine räumliche Umverteilung von Erosions- und Depositionsflächen erreicht. Für die im Untersuchungsgebiet vorliegende räumliche Heterogenität (z. B. Schlaggröße) bieten Landsat-TM-Daten eine ausreichend genaue räumliche Auflösung. Damit wird nachgewiesen, dass die satellitengestützte Fernerkundung im Rahmen dieser Untersuchungen sinnvoll einsetzbar ist. Für eine operationelle Bereitstellung der Parameter mit einem vertretbaren Aufwand ist es erforderlich, die Methoden weiter zu validieren und möglichst weitestgehend zu automatisieren. / Soil erosion models become increasingly more complex and contain physically based components, resulting in changing requirements for their input parameters. The spatial and temporal dynamics of erosions forcing parameters thus produce high requirements on data availability (costs and manpower). Due to this fact, the use of complex erosion models for extensive regions is strongly limited by the high in-situ expense. Moreover, conventional measurement procedures provide parameters at certain points, while remote sensing is a two-dimensional retrieval method.<br /> <br /> This thesis demonstrates, how satellite data can be used as a cost-effective supplementation or alternative to conventional measurement procedures. Leaf area index (LAI) and soil cover percentage are examplarily derived for the EROSION 3D physically based soil erosion model. The main objective of this study is to summarise existing retrieval methods in order to operationally provide such paramaters for soil erosion models or for process models in general. The methods are applied to a catchment in the loess region in Saxony (Germany), that predominantly is agriculturally used. For comparison, simulations based on conventionally estimated parameters for 29 rainstorm events are available [MICHAEL et al. 2000]. <br /> <br /> The remote sensing parameters are derived from Landsat 5 TM data on the following dates: 13.03.1999, 30.04.1999, 19.07.1999. To get temporally continuous data for all events, they are interpolated between the acquisition dates based on the LAI development. Therefore, LAI is firstly calculated for all occurring crops by means of the semi-empirical models of CLEVERS [1986] and BARET & GUYOT [1991]. The coefficients appropriated to these models are taken from literature. Furthermore, a method is investigated that enables coefficient estimation for the Clevers model from Landsat data combined with a simplified growth model. Next, soil cover percentage is derived from LAI after ROSS [1981]. The LAI interpolation is performed by the simplified crop growth model from the SWIM hydrological model [Krysanova et al. 1999]. It has to be mentioned, that plant residue remains unconsidered by the used methods. In comparison to conventional measurement procedures, these methods supply a differentiated mapping of the spatial variability and temporal behaviour regarding the vegetation parameters.<br /> <br /> The simulations with EROSION 3D are carried out for the remotely sensed soil cover percentages, that are retrieved in two ways. Soil cover is directly derived from the remote sensing data for each pixel at the acquisition dates as well as estimated by means of the interpolation for each field on all rainstorm events. In comparison to conventionally determined soil cover, both methods provide an improved spatial allocation of this parameter and thus, a spatial reallocation of erosion and deposition areas. The used Landsat Data provide an adequate spatial resolution suitable for the spatial heterogeneity given in the test area (e. g. field size). These results show that satellite based remote sensing can be reasonably used within the scope of these investigations. In the future, operational retrieval of such remotely sensed parameters necessitates the validation of the proposed methods and in general the automation of involved sub-processes to the greatest possible extent

Expansive soils are a worldwide problem especially in the regions where climate is arid or semi arid. These soils swell when they are exposed to water and shrink when they dry. Cyclic swelling and shrinkage of clays and associated movements of foundations may result in cracking of structures. Several methods are used to decrease or prevent the swelling potential of such soils like prewetting, surcharge loading, chemical stabilization etc. Among these, one of the most widely used method is using chemical admixtures (chemical stabilization). Cyclic wetting and drying affects the swell &ndash / shrink behaviour of expansive soils. In this research, the effect of cyclic swell &ndash / shrink on swell percentage of a chemically stabilized expansive soil is investigated. Class C Fly Ash is used as an additive for stabilization of an expansive soil that is prepared in the laboratory environment by mixing kaolinite and bentonite. Fly ash was added to expansive soil with a predetermined percentage changing between 0 to 20 percent. Hydrated lime with percentages changing between 0 to 5 percent and sand with 5 percent were also used instead of fly ash for comparison. Firstly, consistency limits, grain size distributions and swell percentages of mixtures were determined. Then to see the effect of cyclic swell &ndash / shrink on the swelling behavior of the mixtures, swell &ndash / shrink cycles applied to samples and swell percentages were determined. Swell percentage decreased as the proportion of the fly ash increased. Cyclic swell-shrink affected the swell percentage of fly ash stabilized samples positively.

The Polytrauma/TBI Rehabilitation Center (PRC) of the Veterans Affairs Hospital (VAH) treats patients with Traumatic Brain Injury (TBI). These patients have major motor and cognitive disabilities. Most of the patients stay in the hospital for many months without major improvements. This suggests that patients, family and the VAH could benefit if healthcare provider had a way to better assess or "predict" patients' progression. The individual progress of patients over time is assessed using a pre-defined multi-component performance measure Functional Independence Measures (FIM) at admission and discharge, and a semi-quantitative documentation parameter Clinical Pathway (CP) at weekly intervals. This work uses already de-identified and transformed data to explore developing a clinical outcome predictive model for patients with TBI, as early as possible. The clinical outcome is measured as percentage of recovery using CP scores. The results of this research will allow healthcare providers to improve the current resource management (e.g. staff, equipment, space) through setting goals for each patient, as well as to provide the family more accurate and timely information about the status and needs of the patient.

One of the objectives of disaggregation in hierarchical production planning is to minimize the setup costs incurred when changing production from one family to another. In this research, the setup costs are reduced by determining a production schedule that minimizes the number of setups during the planning horizon. Previous solutions to the disaggregation problem have considered discrete-time, and more recently continuous-time formulations. This research extends the continuous time disaggregation approach by incorporating production schedules allowing backorder. A mathematical formulation and a solution algorithm are presented and the computational complexity and convergence properties of the algorithm are discussed. Experimental results, using both deterministic and stochastic demand patterns, which demonstrate the efficacies of the solution approach are provided.

In children the way of life, nutrition and recreation changed in recent years and as a consequence body composition shifted as well. It is established that overweight belongs to a global problem. In addition, German children exhibit a less robust skeleton than ten years ago. These developments may elevate the risk of cardiovascular diseases and skeletal modifications. Heredity and environmental factors as nutrition, socioeconomic status, physical activity and inactivity influence fat accumulation and the skeletal system. Based on these negative developments associations between type of body shape, skeletal measures and physical activity; relations between external skeletal robustness, physical activity and inactivity, BMI and body fat and also the progress of body composition especially external skeletal robustness in comparison in Russian and German children were investigated. In a cross-sectional study 691 German boys and girls aged 6 to 10 years were examined. Anthropometric measurements were taken and questionnaires about physical activity and inactivity were answered by parents. Additionally, pedometers were worn to determinate the physical activity in children. To compare the body composition in Russian and German children data from the years 2000 and 2010 were used. The study has shown that pyknomorphic individuals exhibit the highest external skeletal robustness and leptomorphic ones the lowest. Leptomorphic children may have a higher risk for bone diseases in adulthood. Pyknomorphic boys are more physically active by tendency. This is assessed as positive because pyknomorphic types display the highest BMI and body fat. Results showed that physical activity may reduce BMI and body fat. In contrast physical inactivity may lead to an increase of BMI and body fat and may rise with increasing age. Physical activity encourages additionally a robust skeleton. Furthermore external skeletal robustness is associated with BMI in order that BMI as a measure of overweight should be consider critically. The international 10-year comparison has shown an increase of BMI in Russian children and German boys. Currently, Russian children exhibit a higher external skeletal robustness than the Germans. However, in Russian boys skeleton is less robust than ten years ago. This trend should be observed in the future as well in other countries. All in all, several measures should be used to describe health situation in children and adults. Furthermore, in children it is essential to support physical activity in order to reduce the risk of obesity and to maintain a robust skeleton. In this way diseases are able to prevent in adulthood. / Die Lebens- und Ernährungsweise sowie die Freizeitaktivitäten von Kindern haben sich im Laufe der letzten Jahre verändert. Daraus resultieren Veränderungen der Körperzusammensetzung. Es ist hinreichend bekannt, dass Übergewicht ein globales Problem ist. Des Weiteren weisen deutsche Kinder ein weniger robustes Skelett auf als noch vor 10 Jahren. Diese Entwicklungen können zu unterschiedlichen Erkrankungen des Herz-Kreislauf-Systems bzw. des Skelettsystems führen. Neben genetischen Faktoren haben Umweltfaktoren wie Ernährung, sozialer Status, die körperliche Aktivität bzw. Inaktivität einen Einfluss auf die Fettakkumulation und das Skelettsystem. Aufgrund der negativen Entwicklungen wurden daher die Zusammenhänge zwischen dem Körperbautyp, Skelettmaßen und der körperlichen Aktivität; die Beziehungen zwischen der äußeren Skelettrobustizität, der körperlichen Aktivität bzw. Inaktivität, dem BMI und dem Körperfettanteil sowie die Entwicklung der Körperzusammensetzung insbesondere die äußere Skelettrobustizität von russischen Kindern im Vergleich zu deutschen Kindern überprüft. In einer Querschnittstudie wurden 691 Jungen und Mädchen im Alter von 6 bis 10 Jahren aus Berlin und Brandenburg untersucht. Es wurden anthropometrische Messungen vorgenommen, Fragebögen bezüglich der sportlichen Aktivität und Inaktivität beantwortet sowie ein Schrittzähler zur Bestimmung der körperlichen Aktivität von den Kindern getragen. Für den internationalen Vergleich der Körperzusammensetzung wurden Daten aus den Jahren 2000 und 2010 von deutschen und russischen Kindern verwendet. Es konnte gezeigt werden, dass der pyknomorphe Körperbautyp die höchste und der leptomorphe Typ die niedrigste äußere Skelettrobustizität aufweisen. Leptomorphe Kinder könnten daher das höchste Risiko für Knochenerkrankungen im Erwachsenenalter aufweisen. Tendenziell zeigen pyknomorphe Jungen eine höhere körperliche Aktivität als die anderen Typen. Dies ist positiv zu bewerten, da die pyknomorphen Typen den höchsten BMI und Körperfettanteil besitzen. Wie die Resultate ergeben, kann die körperliche Aktivität zur Reduktion bzw. Inaktivität zur Erhöhung des BMIs und des Körperfettanteils führen. Die körperliche Inaktivität steigt mit zunehmendem Alter. Die körperliche Aktivität unterstützt weiterhin den Aufbau eines robusten Skeletts. Die äußere Skelettrobustizität ist ebenfalls positiv mit dem BMI assoziiert, so dass dargelegt werden konnte, dass der BMI als Maß für Übergewicht kritisch betrachtet werden sollte. Im internationalen 10-Jahresvergleich zeigt sich eine Zunahme des BMIs bei russischen Kindern und deutschen Jungen. Zurzeit weisen die russischen Kinder immer noch ein robusteres Skelett auf als die Deutschen jedoch ist das Skelett bei russischen Jungen weniger robust als noch vor 10 Jahren. Diese negative Entwicklung sollte weiterhin beobachtet werden auch in anderen Ländern. Alles in allem, sollten immer mehrere Maße zur Beschreibung des Gesundheitszustandes herangezogen werden. Weiterhin ist einer Förderung der körperlichen Aktivität bei Kindern notwendig, um zum einen das Risiko für Übergewicht zu minimieren und zum anderen ein robustes Skelett aufzubauen, um somit Erkrankungen im Erwachsenenalter vorzubeugen.