Compaction caused by certain intensive forest management practices can reduce tree growth, but the causes of growth reduction are usually complex interactions between soil properties and tree species. We used a 7 by 7 factorial greenhouse experiment to create a matrix of bulk density ((Ï b)) and volumetric water content (θv) to determine soil compaction effects on seedling growth of: (i) ponderosa pine (Pinus ponderosa Dougl. ex Laws) grown on Dome and Cohasset soils from California; (ii) shortleaf pine (Pinus echinata) on a Clarksville soil from Missouri; and (iii) loblolly pine (Pinus taeda) on an Argent soil from South Carolina. We also characterized soil physical properties and determined compaction effects on soil strength, air/water balance and least limiting water range (LLWR) for each of the soils. Optimum water content for compaction varied from 19%(Argent) to 34%(Cohasset). Compactive effort curves varied for the four soils;maximum Ï b were 1.33, 1.52, 1.58 and 1.65 Mg m-3 for the Cohasset, Dome, Clarksville, and Argent soils, respectively. Compression indices ranged from 0.33 to 0.38. In general, soil strength increased linearly with a θv decrease at the higher Ï b levels, but the effect varied with each soil type. Cohasset, with the lowest BD, had the highest soil strength (3.5 MPa), while strengths exceeding 2.0 MPa were not found for the Argent soil. Compaction affected the soil water retention curves and associated air/water balance parameters for all soils, particularly the Cohasset and Dome soils. Aeration porosity became limiting at Ï b of 1.3, 1.42, 1.44 and 1.55 Mg m-3 for the Cohasset, Dome, Clarksville and Argent soils respectively. The LLWR was lowest for the Dome and Argent soils (0.3 cm 3 cm-3 ) and in some cases increased with compaction. Models of root growth opportunity were developed using multiple regression. The general model of root length density (RLD) = b0 + b1 θv + b2 Ï b + b3 θv2 described rooting response for the Clarksville-shortleaf and Argent-loblolly soil-species combinations (p = 0.005). However, the root response of ponderosa pine on Cohasset was linear and pine roots in the Dome soil responded to an interaction between θv and Ï b. No model adequately described oak seedling growth as a function of BD and VW. High soil strength at low water contents and low aeration porosity at high water contents limited root growth. Shoot mass of seedlings growing within the least limiting water range (LLWR) was greater than those growing outside the range for all soil-species combinations except the Argent-loblolly pine (p = 0.05). The loblolly pines had greater shoot mass at volumetric water contents above the upper LLWR limits (aeration limiting). The LLWR is a promising method for integrating compaction's influence on soil properties and thus root growth potential since single factors did not appear to adequately explain each soil's compressibility. Furthermore, response surface models of RLD as a function of VW and BD in conjunction with the LLWR and seasonal site water data have potential for determining compaction- induced soil limitations for tree growth, but need to be calibrated for both soil and species. / Master of Science

The master's thesis deals with the steel structures in building industry. The aim of this paper is to propose and statically evaluate the load-bearing steel structure of railway station in Vsetín. After solving the construction load by the roof cladding and external cladding, it follows by an assessment of individual elements of construction, including an assessment of their joints. From a static perspective, the roof structure consists of two diagonal arches which are joined into each other in the top and two longitudinals frames. The entire structure is designed with an emphasis on freedom of internal layout independent of the load-bearing structure.

No description available.

The limiting current technique has widely been used to study liquid-solid mass transfer in various reactor configurations. In the present contribution several underlying physical aspects have been investigated in order to improve the design of mass transfer experiments. Experimentally, the significant influence of electrolyte composition and hydrodynamic conditions have been studied and quantified to ensure conditions of high reproducibility. In the course of single phase COMSOL simulations, different electrode configurations have been examined with emphasis on concentration fields and electric current distribution showing a large sensitivity of the experimental configuration on the absolute current values.

Understanding variation in key functional traits across gradients in high diversity systems and the ecology of community changes along gradients in these systems is crucial in light of conservation and climate change. We examined inter- and intraspecific variation in leaf mass per area (LMA) of sun and shade leaves along a 3330-m elevation gradient in Peru, and in sun leaves across a forest-savanna vegetation gradient in Brazil. We also compared LMA variance ratios (T-statistics metrics) to null models to explore internal (i.e., abiotic) and environmental filtering on community structure along the gradients. Community- weighted LMA increased with decreasing forest cover in Brazil, likely due to increased light availability and water stress, and increased with elevation in Peru, consistent with the leaf economic spectrum strategy expected in colder, less productive environments. A very high species turnover was observed along both environmental gradients, and consequently, the first source of variation in LMA was species turnover. Variation in LMA at the genus or family levels was greater in Peru than in Brazil. Using dominant trees to examine possible filters on community assembly, we found that in Brazil, internal filtering was strongest in the forest, while environmental filtering was observed in the dry savanna. In Peru, internal filtering was observed along 80% of the gradient, perhaps due to variation in taxa or interspecific competition. Environmental filtering was observed at cloud zone edges and in lowlands, possibly due to water and nutrient availability, respectively. These results related to variation in LMA indicate that biodiversity in species rich tropical assemblages may be structured by differential niche-based processes. In the future, specific mechanisms generating these patterns of variation in leaf functional traits across tropical environmental gradients should be explored.

ABSTRACT RATE-LIMITING STEP OF CONE PHOTOTRANSDUCTION RECOVERY AND OGUCHI DISEASE MECHANISMS By Frank Sungping Chen Advisor: Ching-Kang Jason Chen, Ph.D. Retinal photoreceptors provide the first gateway in which light information from the environment is transformed into neuronal signals. The cone and rod photoreceptors are responsible for day and night vision, respectively. Understanding rod and cone phototransduction is to figure out how these cells differ in their temporal and spatial sensitivities to allow perception of a broad dynamic range of stimuli. Phototransduction is mediated through a Gprotein signaling cascade. Light absorption by visual pigment triggers the isomerization of 11- cis-retinal covalently attached to these pigments, which are heptahelical transmembrane Gprotein- coupled receptors. Isomerization of 11-cis-retinal to all-trans-retinal activates the receptor, which catalyzes the exchange of GDP for GTP on the α subunit of heterotrimeric Gprotein called transducin. Activated transducin relieves inhibitory constraint on cGMP-PDE, leading to rapid hydrolysis of cGMP, closure of cGMP gated cation channels, and membrane hyperpolarization. In order for photoreceptor to be responsive to light again, this robust phototransduction pathway must be deactivated in a timely fashion and this involves several reactions simultaneously. First, the activated opsin must be phosphorylated by G-protein-coupled receptor kinases (GRKs) and capped by arrestin binding. Second, activated transducin must hydrolyze bound GTP through intrinsic GTPase activity, which is accelerated by a GTPase accelerating protein (GAP) complex comprised of RGS9-1/Gβ5-L/R9AP. Mutations in human genes involved in these reactions cause various visual defects. Cone, by and large, uses the same set of genes for pigment and transducin deactivations but it has lower sensitivity and faster kinetics than rod and is responsible for high visual acuity. During phototransduction recovery in which multiple reactions take place, the slowest reaction will determine the overall rate of recovery. In rod, this so-called, rate-limiting step has been determined to be transducin deactivation. It is unknown whether cone transducin deactivation also controls the timing of conerecovery, although we and others have shown that cone possesses a higher level of GAP concentration. In this thesis, the rate-limiting step in cone phototransduction recovery has been unequivocally determined by overexpressing RGS9-1 by 2.7 fold in mouse cones, which results in accelerated cone recovery. Complementarily, we find that ectopically expressing a human cone opsin kinase GRK7 in mouse cones does not affect cone recovery. These results altogether demonstrate that the rate-limiting step of cone recovery is the GTP-hydrolysis of cone transducin, not the opsin phosphorylation by GRKs. By elucidating the rate-limiting step of photoreceptor recovery, we have revealed the importance of G-protein cycling in timing of both rod and cone photoreceptors. This may further be generalized to other physiological processes controlled by heterotrimeric G-proteins. The proper shutoff of phototransduction is essential for normal vision as recovery defects lead to visual impairment. Even though the reaction catalyzed by GRK1 is not rate-limiting, mutations of this important gene render rhodopsin phosphorylation and deactivation the slowest step in rod recovery and create a pathological condition. GRK1 mutations have been found in Oguchi disease patients, who suffer from congenital stationary night blindness. One of the mutations, V380D, is investigated in detail in this study. Transgenic expression of GRK1 V380D mutant in rods reveals a kinase with reduced expression and catalytic activity. While V380D GRK1 is found capable of inactivating rhodopsin, the reduction in kinase activity leads to a delayed dark adaptation, and is congruent with the night blindness phenotype observed in Oguchi disease patients. Finally, we have also investigated the role of post-translational isoprenylation on GRK1 function. We found that isoprenylation is required for GRK1 membrane association and outer segment targeting. Altogether our data add significantly to understanding the structure and function of GRK1, which is one of the least understood molecules involved in vertebrate phototransduction.

Les bactéries du genre Deinococcus sont des microorganismes qui présentent des propriétés remarquables de résistance aux conditions extrêmes telles que les radiations ionisantes, les stress oxydatifs, la dessiccation ou encore les températures extrêmes. L’exploitation de leurs capacités présente donc un réel intérêt pour les procédés biotechnologiques de production de métabolites d’intérêt, les biocarburants. Néanmoins, la physiologie et le métabolisme de ces microorganismes ont été très peu étudiés à ce jour. L’objectif de ce travail est d’identifier les exigences nutritionnelles d’une souche de déinocoques, Deinococcus geothermalis, dans le but de définir la composition d’un milieu synthétique permettant une croissance sans limitation. L’étude statistique de quarante huit formulations de milieux de culture a mis en évidence la variabilité qualitative et quantitative des compositions des milieux utilisés pour leur culture. Il ressort que l’ajout de facteurs stimulant la croissance, sous forme d’extrait de levure, est indispensable à la croissance non limitée de la souche Deinococcus geothermalis DSM 11300. En bioréacteur à 45 °C, sur un milieu complexe et substrat glucose, une concentration finale de 2,7 gMS.L-1 a été obtenue en six heures avec un taux de croissance égal à 0,65 h 1. Les résultats ont montré une variabilité intra-espèce importante ; parmi les trois souches de Deinococcus geothermalis étudiées, DSM 11300, DSM 11301 et DSM 11302, la souche Deinococcus geothermalis DSM 11302 présente la meilleure croissance en termes de nombre de générations, en milieu défini ou complexe. L’étude de l’influence des étapes de préparation de l’inoculum a permis de standardiser les conditions de préparation de l’inoculum préalablement aux cultures en bioréacteur. La souche Deinococcus geothermalis DSM 11302 présente une croissance exponentielle durant quatre heures en bioréacteur sur un milieu défini avec 10 g.L-1 de glucose ; le taux de croissance de 0,25 h-1 ne se maintient pas sur une durée plus longue. Le rendement de production de biomasse à partir du glucose atteint 0,25 gX.gGlc-1 soit 0,30 CmolX.CmolGlc-1. L’ajout de sources carbonées, sources soufrées, vitamines ou autres facteurs de croissance ne permet pas d’améliorer la croissance de la souche dans ces conditions. Sur ces bases, la quantification de la physiologie de Deinococcus geothermalis DSM 11302 a été étudiée lors d’une culture en mode discontinu alimenté avec une stratégie d’apport de deux substrats, l’extrait de levure et le glucose. Le mode de conduite a permis de révéler que le glucose n’est pas la source de carbone assimilée préférentiellement et que l’extrait de levure peut être consommé comme source azotée organique et/ou comme source carbonée. Les déinocoques sont caractérisés par un métabolisme principalement protéolytique : il a été possible de confirmer que l’extrait de levure est indispensable à la croissance non limitée de Deinococcus geothermalis DSM 11302. Avec cette stratégie d’alimentation co-substrats, 253 g d’extrait de levure et 26 g de glucose ont été ajoutés pour produire 99 gMS de biomasse soit 9,6 gMS.L-1 en six heures. Les vitesses spécifiques maximales de consommation des substrats, extrait de levure et glucose, atteignent respectivement 0,68 et 0,39 Cmol.CmolX-1.h-1. Le taux de croissance exponentiel maximal obtenu est égal à 1.05 h-1, meilleur résultat décrit à ce jour pour un déinocoque. Ces résultats contribuent ainsi à implémenter l’état des connaissances sur la physiologie et les exigences nutritionnelles de Deinococcus geothermalis et donnent accès aux valeurs de paramètres cinétiques et de rendements, données absentes de la littérature / Bacteria belonging to Deinococcaceae family are microorganisms with exceptional resistance properties to extreme environmental conditions such as ionizing radiations, oxidative stress, dehydration or extreme temperatures. These properties make them interesting targets for biotechnological processes for metabolite production like biofuels. Nevertheless, physiological behaviour and metabolism of these microorganisms have been little studied to date. The main objective of this work was to study the nutritional requirements for the growth of a Deinococcaceae strain, Deinococcus geothermalis, in order to define a synthetic medium sufficient for a non-limiting growth of this strain. The statistical study of 48 culture media formulations highlighted a lot of variability between the compositions used for their growth. A limiting growth of the strain Deinococcus geothermalis DSM 11300 was obtained on the defined medium DM chosen for this work, in Erlenmeyer flasks and in bioreactor, unless yeast extract was added to the medium. Cultivated in a bioreactor at 45 °C, on a complex medium with glucose (CMG), the biomass concentration reached 2.7 gMS.L-1 in six hours with a growth rate of 0.65 h-1. The results showed intra-specie variability; the strain Deinococcus geothermalis DSM 11302 exhibits the best number of generation in both complex and defined media. The study of the influence of inoculum preparation steps allowed standardizing the conditions of inoculum preparation before cultures in bioreactor. The strain Deinococcus geothermalis DSM 11302 has a four hours exponential growth when cultured in bioreactor on the defined medium DM at 45 °C, but the maximal growth rate of 0.28 h-1 decreases rapidly. The yield of biomass production on glucose reached 0.25 gX.gGlc-1 (0.30 CmolX.CmolGlc-1). Oxygen uptake and glucose specific uptake rates were 3.3 mmol.L-1.h-1 and 0.57 CmolGlc.CmolX.h-1 respectively. None of the carbon sources, sulfur sources or growth factors added to the defined medium DM could improve growth results of the strain Deinococcus geothermalis DSM 11302. For the quantification of Deinococcus geothermalis DSM 11302 physiology, a fed batch culture strategy with a yeast extract and glucose co-substrate feed was chosen. This strategy revealed that glucose is not the preferential carbon source for biomass production. In addition, yeast extract can be consumed as organic nitrogen source and/or as carbon source. Deinococcaceae are mainly proteolytic microorganisms, yeast extract is an essential element to obtain a non-limiting growth of Deinococcus geothermalis DSM 11302. With this co substrate feed strategy, 253 g of yeast extract and 26 g of glucose were added to produce 99 gMS of biomass or 9.6 gMS.L-1 in six hours. The maximal yeast extract and glucose specific uptake rate reached respectively 0.68 and 0.39 Cmol.CmolX 1.h 1. The maximal exponential growth rate is 1.05 h-1, which is the best result describes to date for a Deinococcaceae strain. These results implement the knowledge on physiology and nutritional requirements of Deinococcus geothermalis and give access to quantitative values for characteristic kinetic parameters and conversion yields

Sob a égide de um Direito Penal garantista, calcado, sobretudo, no respeito aos princípios constitucionais, e com o fim de coadunar o mal da pena com o cerne de todo o sistema que é a máxima da dignidade da pessoa humana, novos temas emergem da realidade social, provocando reflexões no sentido de se atualizar o Direito e seus institutos com as necessidades de uma sociedade que está cada vez mais dinâmica em suas relações. Devido à amplitude e importância de seu conceito, a culpabilidade vem sendo objeto de estudo, afinal, de acordo com a sistemática adotada pelo Código Penal brasileiro, este instituto corresponde ao cerne da Teoria do Delito. A partir dos estudos sobre a culpabilidade, surge a teoria da coculpabilidade que, por sua abrangência conceitual, hoje se considera princípio de origem constitucional. A reflexão parte da gritante desigualdade socioeconômica que se vislumbra atualmente dentro do grupo social, a qual se reforça pela omissão do Estado na efetivação das políticas públicas que possibilitam o acesso dos cidadãos aos direitos sociais, e do fato incontroverso que o meio no qual a pessoa vive condiciona a formação de sua personalidade e, consequentemente, a eleição de seus comportamentos. Atrela-se a isso o caráter seletivo que o sistema penal assume quando se verifica na realidade fenomênica sua utilização equivocada como mecanismo corretor de problemas como a incapacidade estatal de cumprir os deveres constitucionais no que atine à concreção do bem comum. A coculpabilidade, então, coloca o Estado e a sociedade para dividirem a culpabilidade pelo crime com a pessoa do delinquente, uma vez que se constate no caso concreto que esta foi privada do acesso aos seus direitos fundamentais por negligência estatal; essa divisão de responsabilidade pelo delito se dá na limitação do direito de punir. O reconhecimento do princípio da coculpabilidade como vigente no Estado Democrático de Direito apresenta-se um tanto controverso ainda na jurisprudência e na doutrina penal brasileira. Tem por objeto a presente pesquisa analisar o alcance de referido princípio e sua aptidão de atenuar ou mesmo excluir a pena, situando-o na Teoria do Delito como mecanismo eficaz para a concreção do Direito Penal mínimo. / Under the aegis of a criminal garantista law, trampled, especially in respect to constitutional principles, and consistent with the end of the of the penalty with the evil core of the whole system which is the maximum of human dignity, new themes emerge from the social reality, causing reflections in order to update the law and its institutions to the needs of a society that is increasingly dynamic in their relationship. Due to the breadth and importance of its concept, culpability has been the object of study, after all, according to the system adopted by the Brazilian Penal Code; this corresponds to the core Theory of Crime institute. Based on the studies on the guilt arises the co culpability theory which in conceptual comprehensiveness, today it is considered a constitutional principle of origin. The reflection part of whopping socioeconomic inequality that can be seen today within the social group, which is reinforced by the omission of the state in the fulfillment of public policies that enable citizens\' access to social rights, and the incontrovertible fact that the way in which a person lives affects the formation of his personality and therefore the election of their behaviors. It attaches itself to the selective character the penal system assumes that when there is in fact phenomenalistic use as mistaken a mechanism broker problems such as the inability to meet the state constitutional duties concerning the concretion of the common good. The co culpability then puts the state and society sharing culpability by crime with the person of the delinquent, since it is found in this case was deprived of access to their fundamental rights by state neglect, this division of responsibility for the crime occurs on limiting the right of punishing. The recognition of the principle of co culpability as existing in a democratic state has become somewhat controversial even in Brazilian criminal jurisprudence and doctrine. Aims at the present research to analyze the scope of this principle and its capacity to mitigate or even delete the sentence, placing it on the Theory of Crime as an effective mechanism for the concretion of minimal Criminal Law.

Neste trabalho, com objetivo de desenvolvermos dispositivos de limitação óptica, estudamos o processo de absorção de estado excitados em um grupo de tetrapiridil porfirinas com diferentes substituintes centrais (2H+, Zn2+, Ni2+, Cu2+). Para isso utilizamos a técnica de varredura – Z com pulsos de femto e picossegundos bem como com trem de pulsos. Desta forma, determinamos a dinâmica de absorção de estados excitados, para estas moléculas, obtendo parâmetros espectroscópicos tais como tempo de cruzamento intersistema, e as seções de choque de absorção dos primeiros estados excitados singleto e tripleto. Além disso, visando aproveitar os processos ópticos acumulativos de alguns materiais não lineares, em aplicação de limitação óptica, desenvolvemos uma nova geometria óptica denominada de limitador óptico de múltiplas passagens, a qual utiliza dois espelhos esféricos confocais e um espelho plano posicionado paralelamente a linha que une os espelhos esféricos. / In this work, aiming to develop optical limiting devices, we have studied excited state absorption process in a group of tetrapyridyl porphyrins with different central substitutes (2H+, Zn2+, Ni2+, Cu2+). We have employed Z-scan technique with femto and picosecond pulses as well as with pulse trains to determine the excited state absorption dynamics and obtain some spectroscopic parameters like intersystem crossing time and triplet and singlet excited state absorption cross-sections. Moreover, we have developed a new geometry for an optical limiter, named multipass optical limiter. It is formed by two confocal spherical mirrors together with a plane mirror placed in parallel with the line joining them.

Neste trabalho, consideramos os efeitos de um campo magnético ressonante externo sobre o plasma confinado em um tokamak. Este campo magnético pode ser produzido quer por condutores helicoidais ou por um limitador magnético caótico. O principal propósito desse campo magnético ressonante é criar uma região de linhas de força caóticas na borda da coluna de plasma que pode melhorar o confinamento do plasma. O campo magnético de equilíbrio foi obtido resolvendo-se a equação de GRAD-SHAFRANOV em um sistema de coordenadas intrinsecamente toroidal (as coordenadas polares toroidais). Obtivemos o campo magnético, gerado pelos condutores helicoidais, através da solução explícita da equação de LAPLACE no mesmo sistema de coordenadas. A partir desse campo magnético, tomando o termo de mais baixa ordem, obtivemos analiticamente um mapa estroboscópico simplético para um conjunto de anéis limitadores magnéticos caóticos. Calculamos esse mapa estroboscópico simplético usando uma formulação hamiltoniana e adotando a. ação dos limitadores magnéticos caóticos como uma sequência de pulsos do tipo função delta. Com esse mapa estroboscópico simplético, caracterizamos algumas ilhas magnéticas ressonantes e a transição para um regime de caos global através da superposição das mesmas. Usamos esse mapa estroboscópico simplético para estudar o transporte das linhas de força na borda da coluna de plasma. A perda de linhas de força caóticas, que atingem a parede interna do tokamak, segue uma distribuição de POISSON. Calculamos, ainda, o número médio de voltas, ao redor da câmara de vácuo, necessárias para que uma linha de força caótica atinja a parede da câmara. / In this work, we have considered the effects of an external resonant magnetic field on the plasma confined in a tokamak. This resonant field can be produced by helical windings or by a chaotic magnetic limiter. The main purpose of this resonant magnetic field is to create a region of chaotic field lines at the edge of the plasma that can improve the confinement of the plasma. The equilibrium tokamak field was obtained by solving the GRAD-SHAFRANOV equation in an intrinsically toroidal coordinate system (the toroidal polar coordinates). We have obtained the magnetic field which has been generated by helical windings through an explicit solution of the LAPCACE equation in the same coordinate system. From this magnetic field, taken in its lowest order, we have analytically obtained a sympletic stroboscopic map for a set of chaotic magnetic limiters. We have calculated this sympletic stroboscopic map by using a Hamiltonian formulation and by supposing the action of the chaotic magnetic limiters as a sequence of delta-function pulses. With this sympletic stroboscopic map we have characterized some resonant magnetic islands and the onset of global chaos through their overlap. We have used this sympletic stroboscopic map in order to study the transport of the field lines at the edge of the plasma. The loss of chaotic field lines that reach the inner wall of the tokamak follows a POISSON distribution. We have also calculated the average number of toroidal turns for a chaotic field line to reach the inner wall of the tokamak.