Located just east of Missoula, Montana, Milltown Dam stood from 1908 to 2008 immediately downstream of the Clark Fork River’s confluence with the Blackfoot River. After the discovery of arsenic-contaminated groundwater in the nearby community of Milltown, as well as extensive deposits of contaminated sediment in the dam’s upstream reservoir, in 1981, the area was designated a Superfund site – along with much of the Upper Clark Fork Watershed. This motivated the eventual decision to remove the dam, perform environmental remediation, and reconstruct approximately five kilometers of the Clark Fork River and its floodplain. This study is part conceptual and part empirical. It describes a state-and-transition framework equipped to investigate channel evolution as well as the adjustment trajectories of other socio-biophysical landscapes. This framework is then applied to understand the post-restoration channel evolution of the Clark Fork River’s mainstem, secondary channels, and floodplain. Adopting a state-and-transition framework to conceptualize landscape evolution lets environmental managers more effectively anticipate river response under multiple disturbence scenarios and therefore use more improvisational and adaptive management techniques that do not attempt to guide the landscape toward a single and permanent end state. State-and-transition models can also be used to highlight the spatially explicit patterns of complex biophysical response. The state-and-transition models developed for the Clark Fork River demonstrate the possibility of multiple evolutionary trajectories. Neither the secondary channels nor the main channel have responded in a linear, monotonic fashion, and future responses will be contingent upon hydrogeomorphic and climatic variability and chance disturbances. The biogeomorphic adjustments observed so far suggest divergent evolutionary trajectories and that in some instances the long-term fates of the mainstem, floodplain, and secondary channels are inescapably enmeshed with one another.

Organic and inorganic nanostructured materials, nano- and mesoscale objects and devices, and their integration into existing microelectronic technologies have been at the center of recent fundamental and applied research in nanotechnology. One of the critical needs is to develop an enhanced predictive capability of structure-property correlations and enable robust high performance systems by design. My thesis work was concerned with the theoretical and experimental studies of electronic and mechanical properties of chemically functionalized nanowires. I will describe a theoretical approach for investigating structure-property correlations in atomic-sized metallic wires based on the Density Functional Theory (DFT) for structure calculations and the Non-equilibrium Green's Function (NEGF) technique for electronic transport properties simulations. This synergistic approach is shown to yield the atomic structure of the smallest niobium nanowires. Furthermore, the method was applied to simulate electronic properties of chemically functionalized graphene nanoribbons. Further, I will demonstrate an experimental technique for simultaneous measurements of force and conductance in atomic-size objects based on quartz tuning fork piezoelectric sensors. A peculiar scaling effect, relevant for a broad range of test and measurement applications, namely the squeeze film effect, was observed during the development of the sensors. Using theoretical analysis based on finite element simulations of the hydrodynamic behavior of the sensors in a broad range of ambient conditions, I explain the observed phenomenon.

Orientador: Daniel Mario Ugarte / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin / Made available in DSpace on 2018-08-15T02:39:35Z (GMT). No. of bitstreams: 1 Oiko_VitorToshiyukiAbrao_M.pdf: 7596860 bytes, checksum: c9ed7c1eff25bf830795b90b88bdc6fa (MD5) Previous issue date: 2010 / Resumo: O estudo de nano-sistemas tem atraído grande atenção nos últimos anos, principalmente devido às suas possíveis e novas aplicações tecnológicas. Muitos esforços têm sido feitos nessa área, porém há ainda várias questões em aberto com relação à compreensão de nanoestruturas. Um dos principais desafios diz respeito à manipulação e o posicionamento controlado de nano-objetos, juntamente com a quantificação das forças envolvidas e a caracterização das propriedades mecânicas em nanoescala. Muitos avanços foram atingidos com a combinação de técnicas de microscopia de força atômica (AFM). Infelizmente nestes experimentos o sensor de forças também é utilizado para gerar uma imagem da amostra. Assim não é possível visualizar o nano-sistema ao mesmo tempo em que ele é submetido a algum esforço mecânico. Outros experimentos são realizados in situ em microscópios eletrônicos onde são utilizados porta-amostras especiais com sensores de força de microscópios de AFM.Combina-se dessa forma a capacidade de se observar diretamente o nano-sistema com a de aplicar e medir forças em sistemas nanométricos. Nesta dissertação é estudada então uma alternativa para a fabricação de um sensor de forças baseado no uso de diapasões de quartzo (tuning forks). Esse sensor deverá ser utilizado em experimentos de nanomanipulação. Este projeto abordou todos os aspectos necessários à instrumentação, desenho, construção e implementação do sensor. O sensor foi acoplado a um nanomanipulador que opera dentro de um microscópio eletrônico de varredura de alta resolução. Com essa montagem, realizaram-se experimentos preliminares de manipulação e deformação de nanofios semicondutores (InP, de alguns mícrons de comprimento, e de 50-200 nm de diamêtro). As forças foram quantificadas baseando-se nas imagens de microscopia dos fios sendo deformados e utilizando um modelo teórico de deformações elásticas. Esses valores foram correlacionados com as variações das curvas de ressonância do tuning fork, para finalmente obter a calibração do sensor de forças. O sistema permite medir forças com uma sensibilidade de 0:5m N baseando-se somente nas mudanças dos sinais elétricos utilizados para alimentar o diapasão de quartzo / Abstract: The study of nanosystems has attracted great attention in recent years, mainly due to their novel possible technological applications. Many efforts have been made in this area, however there are still several open questions concerning the comprehension of such systems. One of the biggest challenges is the manipulation and the controlled positioning of nano-objects, together with the quantification of the forces involved and the mechanical characterization at the nanoscale. Many advances have been achieved with the combination of atomic force microscopy (AFM) techniques. Unfortunately, in these experiments the force sensor is also applied to generate the sample's images. It doesn't allow the system's visualization simultaneously with the stress application. Other experiments are performed in situ electron microscopes where special sample-holders with AFM cantilevers are used. It combines then the ability of observing the nanosystem directly to the possibility of applying and measuring forces in nanometric scale. In this dissertation it is studied an alternative to the fabrication of a force sensor based on quartz tuning forks. This sensor will be used on nanomanipulation experiments. The project covered all the aspects necessary to the sensor's instrumentation, design, construction and implementation. The sensor was attached to a nanomanipulator that operates inside a high resolution scanning electron microscope. Semiconductor nanowires (InP, a few microns in length and 50-200nm in diameter) were manipulated and deformed with this experimental setup. The force quantification was based on microscopy images of the deformed nanowires and on theoretical model of elastic deformations. The force values were correlated with the variations of tuning fork's resonant curves in order to obtain a calibration curve for the sensor. Sensitivity of 0:5m N were achieved based only on changes on electrical signals fed to the quartz tuning fork / Mestrado / Física da Matéria Condensada / Mestre em Física

This thesis describes the implementation of a source to source compiler that translates Fork language to REPLICA baseline language. The Fork language is a high-level programming language designed for the PRAM (Parallel Random Access Machine) model. The baseline language is a low-level parallel programming language for the REPLICA architecture which implements the PRAM computing model. To support the Fork language on REPLICA, a compiler that translates Fork to baseline is built.  The Fork to baseline compiler is built in compatibility with the Fork implementation for SB-PRAM. Moreover, the libraries that support Fork's features are built using baseline language.The evaluation result verifies that the features of the Fork language are supported in the implementation. The evaluation also shows the scalability of our implementation and shows that the overhead introduced by Fork-to-baseline translation is small.

Hand Arm Vibration Syndrome (HAVS) is a collective term for the symptoms arising from the prolonged use of vibrating hand tools. An investigation into the literature on available screening tools for HAVS was conducted. A screening tool is used for the quick identification of certain symptoms without a full medical check up, and is for use by mine medical personnel for the determination of workers with HAVS symptoms and those without. Twenty-two non-exposed volunteers were tested with the screening tools and forty-two rock drill operators. Only the rock drill operators had a medical examination and standardised tests for HAVS diagnoses, to determine their HAVS diagnosis and severity. This diagnosis was used as the standard for the evaluation, of existing screening tools and for developed screening tool, sensitivity for the detection of HAVS symptoms. The screening tools chosen were a traditional tuning fork, a similar tuning fork but mounted into a box with a set excitation unit and a two-point discriminator set a 3mm, 6mm, and 10mm apart. The results showed that a screening questionnaire that specifically focuses on the symptoms of HAVS has better sensitivity and specificity to identify cases. A two-point discriminator with variable distance points, where patients have to distinguish between one pin prick and two, was able to identify HAVS cases when the distance was set at 3mm. However, the sensitivity of the two-point discriminator was lower than the sensitivity of the questionnaire. / Dissertation (MSc)--University of Pretoria, 2007. / Industrial and Systems Engineering / Unrestricted

Orientadores: Daniel Mario Ugarte, Varlei Rodrigues / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-24T10:25:30Z (GMT). No. of bitstreams: 1 Oiko_VitorToshiyukiAbrao_D.pdf: 44112591 bytes, checksum: 93cb68b7fac3caf690848f58147ff259 (MD5) Previous issue date: 2014 / Resumo: O estudo de nano-sistemas tem atraído grande atenção nos últimos anos, principalmente devido às suas possíveis e novas aplicações tecnológicas. Muitos esforços tem sido feitos nessa área, porém há ainda várias questões em aberto com relação a compreensão de nanoestruturas. Um dos principais desafios diz respeito à manipulação e o posicionamento controlado de nanoobjetos, juntamente com a quantificação das forças envolvidas e a caracterização das propriedades mecânicas em nanoescala. Muitos avanços foram atingidos combinando-se a microscopia eletrônica de varredura (SEM) e a de força atômica (AFM), realizando experimentos in situ que aproveitam a resolução e a formação de imagens do SEM, e a capacidade de medir forças em sistemas nanométricos do AFM. Nesta tese discutimos a quantificação de forças de intensidade < N, aplicadas em experimentos de nanomanipulação in situ de SEM, através do desenvolvimento de um sensor baseado no uso de diapasões de quartzo (tuning fork). Abordamos os aspectos técnicos relevantes à construção do sensor e seu funcionamento, desde o problema de se medir forças da ordem de nN em nano-objetos individuais, até sua aplicação em sistemas dessa dimensão. Pontos fundamentais do desenvolvimento como a definição da sua configuração, da eletrônica de aquisição e da metodologia de calibração e de aplicação são tratados em detalhe. Um processo de calibração baseado na deformação in situ de cantilevers de AFM é utilizado para permitir a quantificação da força. Subsequentemente a medida dos valores é feita exclusivamente através das curvas de ressonância do tuning fork, independendo completamente das imagens de microscopia. Forças no intervalo de 1-100 nN foram medidas, e a aplicação do sensor foi dada no intervalo de 4-40 nN. A precisão obtida na quantificação foi de alguns nN, ?F ?1-4 nN. O sistema foi testado em experimentos de deformação de bundles de nanotubos de carbono in situ em um SEM, nos quais medimos quantitativamente a influência das forças de van der Waals no atrito dinâmico durante o escorregamento entre nanotubos. As forças obtidas nesses experimentos variaram entre 14-35 nN / Abstract: The study of nanosystems has attracted many attention in recent years, mainly due to their novel possible technological applications. Many efforts have been made in this area, however several open questions regarding the comprehension of such structures remain. A major challenge concerns the manipulation and the controlled positioning of nano-objects, together with the quantification of the involved forces and the mechanical characterization at the nanoscale. Many advances have been achieved by combining the scanning electron microscopy (SEM) and the atomic force microscope (AFM), conducting thus in situ experiments that profit from SEM¿s resolution and imaging and from AFM¿s ability to measure forces in nanoscale systems. In this thesis we treat the quantification of forces with intensity < N applied during in situ nanomanipulation experiments performed inside a SEM by developing a force sensor based on quartz tuning forks. Our approach comprises the technical aspects relevant to the sensor¿s assembly and its operation, from the issue of measuring forces of the order of nN on individual nano-objects, to its application on nanosystems. Key points of development such as the sensor¿s design, electronics, calibration and applications are described in details. A calibration process based on the in situ bending AFM cantilevers is carried out to enable the force quantification. Subsequently the force measurement is done exclusively by the TF¿s resonance curve, being completely independent of the microscopy images. Forces in the range of 1-100 nN were measured, and the sensor¿s application was considered between 4 nN and 40 nN. The precison acquired was of a few nN, ?F ?1-4 nN. To test the sensor in situ strain experiments were performed on bundles of carbon nanotubes from which we measured quantitatively the van der Waals¿ influence on the dynamic friction during the sliding of adjacent bundles. The forces acquired were then in the range of 14-35 nN / Doutorado / Física / Doutor em Ciências

Des stress réplicatifs sont rencontrés à chaque phase S du cycle cellulaire et différents mécanismes permettent leur prise en charge. La recombinaison homologue (RH) tient un rôle important dans le maintien de la stabilité du génome au cours de la réplication. En effet, la RH escorte la progression des fourches et prévient les défauts mitotiques. Toutefois, le lien moléculaire entre le stress réplicatif et les défauts mitotiques n’est pas élucidé. De façon générale, les fourches de réplication bloquées peuvent être sauvées grâce à leur fusion avec la fourche convergente ou au redémarrage de fourche par la RH. Le laboratoire a développé un essai génétique reposant sur l’utilisation d’une barrière de réplication conditionnelle afin d’étudier le mécanisme par lequel la RH contribue au sauvetage des fourches de réplication bloquées. L’équipe a montré que le redémarrage des fourches bloquées par la RH est conditionné par l’exposition d’un ADNsb et non d’une cassure double-brin. Ainsi, les fonctions de la RH au cours de la gestion du stress réplicatif peuvent être adressées indépendamment de sa fonction de réparation des cassures (fonction relativement bien documentée). Les travaux décrits dans ce manuscrit s’inscrivent autour des mécanismes que la RH engage afin d’assurer la stabilité génétique en réponse au stress réplicatif. Plus précisément, je me suis intéressée à l’implication des facteurs de la RH dans la protection des fourches de réplication bloquées au niveau moléculaire et cellulaire. En absence de la recombinase Rad51 ou de son chargeur Rad52, le blocage d’une seule fourche de réplication est suffisant pour induire des défauts mitotiques, incluant des ponts anaphasiques (lien physique entre chromatides sœurs). Il s’avère que les fourches bloquées sont extensivement dégradées par la nucléase Exo1 en absence de Rad51/Rad52. De manière intéressante, l’accumulation excessive d’ADNsb à la fourche est à l’origine de la non-disjonction des chromatides sœurs en mitose et ce malgré l’arrivée de fourches convergente. Ainsi, les fourches de réplication non protégées sont le siège de terminaison pathologique mettant à mal la ségrégation des chromosomes. La RH étant impliquée dans la protection et le redémarrage des fourches de réplication, l’utilisation du mutant de séparation de fonction Rad51-3A a permis de montrer que ces deux fonctions sont génétiquement séparables. Les fourches de réplication protégées et incapables d’être redémarrées par la RH ne présentent pas de symptômes de terminaison pathologique. Ainsi, au-delà de sa capacité à redémarrer les fourches inactivées, les facteurs de la RH assurent la complétion de de la réplication en maintenant les fourches de réplication dans une conformation propice à une fusion avec la fourche convergente. Ces résultats contribuent à une meilleure compréhension des mécanismes moléculaires invoqués par la RH afin de maintenir la stabilité génétique au cours du stress réplicatif. / At each cell cycle, cells undertaking the DNA replication process face several sources of replication stress (RS) compromising the progression of the replicating forks and threatening both chromosome duplication fidelity and their correct segregation during mitosis. Replication stresses emerged as a major source of genetic instability and cancer development. Several mechanisms, among which homologous recombination (HR), operate to buffer the deleterious effects of RS. HR acts as an escort to fork progression and prevents mitotic defects. Nonetheless, the molecular connection between replication stress and mitotic defects remains elusive. A conditional replication fork barrier (RFB) acting in a polar manner was developed in the lab to terminally-arrest fork progression. In this system, HR functions handling replication stress can be assessed independently of its well-known function in double strand break repair. The work described here aims to understanding the mechanism that HR performs to ensure genetic stability in response to replication stress. In general, blocked replication forks can be rescued either by fork convergence or by active HR-mediated fork restart. However, in absence of Rad51 recombinase or it loader Rad52, a single activated RFB is sufficient to induce mitotic abnormalities including anaphase bridges. The involvement of HR factors in fork protection was explored at the molecular and cellular levels. It turns out that terminally-arrested forks are extensively resected by the Exo1 nuclease in the absence of Rad51/Rad52. Interestingly, the excess of ssDNA accumulation at the fork triggers sister chromatid non-disjunction in mitosis despite the arrival of an uncorrupted converging fork to rescue replication. Thus, unprotected replication forks are prone to pathological termination threatening chromosome segregation. HR being involved in fork protection and restart, the use of a Rad51 mutant showed that these two functions are genetically separable. Indeed, protected forks unable to restart by HR do not show any pathological termination. Thus, beyond their ability to restart inactivated forks, HR factors ensure replication completion by maintaining the forks in a suitable conformation for a fusion with the converging fork. Overall, these results shed light on the molecular events engaged by RH to ensure genome stability in response to replication stress.

This master's thesis deals with design of equatorial fork mount for astronomical telescope. The issue of space object watching equipment is deeply analysed. The enclosures of analysis are used in design project. Important aspects are accuracy of motion and high resolution of mount. These parameters are compared with series manufactured equatorial mounts.

This paper analyses the EU’s European Green Deal and the changes to Food production it seeks to implement in its Farm to Fork Strategy, introduced in 2019. Attempting to establish whether or not it will enable them to succeed in meeting their goal of a 55% reduction of Green House Gas Emissions by 2030. The analysis on the EU’s food production system is done using a theory which looks at the production efficiency, the shift of diets and the reduction of food waste that the strategy seeks to implement. Arguing that specific shifts in these categories must be made if the EU’s climate goals are to be met. This is then compared to the actual policies implemented in the Farm to Fork Strategy. The thesis concludes that, while the EU succeeds in its food waste preventions as well as some aspects of its production efficiency, it is lacking in its strategy regarding shifting diets and that, in order to meet its climate goals, substantial shifts will need to be made in this category.

The project set out to develop a non-typological approach to public space in a poly-centric city. The principle of third space was used to conceptualise an interface for public life that would potentiate both public and private realms, and mitigate the issues currently related to contemporary public space. The notion of third space was also considered for the projects programmatic response in order to achieve an authentic urban experience. In essence a bridge between industrial typology and retail space was proposed to remedy the state of the unconscious consumer as well as establish the cross-fertilisation that occurs when a larger demographic of users are present. / Mini Dissertation (MArch (Prof))--University of Pretoria, 2020. / Architecture / MArch (Prof) / Unrestricted