Meditations

My early work was very much influenced by the energetic and emotional qualities found in Louise Fishman’s and Joan Mitchell’s paintings. I wanted my work to draw the viewer into the depths of the painting; however the sudden deaths of my grandfather and father within months of each other had an extremely profound effect on me and my artwork. I was no longer able to invite the viewer beyond the surface of my work, because I was too afraid to delve deeper into my own emotions. While pursuing my MFA at Rochester Institute of Technology, I was able to refine and simplify my work through influences from Process Art, Minimalism, and Abstract Expressionism. A final body of work developed, which employed the use of multiple canvases in each piece with a monochromatic color palette and undulating lines that wound across and over their edges, suggesting connectedness between parts. The final body of work became therapeutic and representative of artifacts and maps, which allowed me to examine both my past and places where I had been while also suggesting pathways into the future. For me, the practice of making art became a form of meditation, a way for me to free myself from disruptive thoughts, hesitation, and emotion. It allowed me to tap into my intuition, and let the composition of the work develop without premeditation. By focusing on the meditative qualities of producing a final body of work, I was able to become a more complete and healthy version of myself

Applications of the Ashtekar gravity to four dimensional hyperk\"ahler geometry and Yang-Mills Instantons

The Ashtekar-Mason-Newman equations are used to construct the hyperk\"ahler metrics on four dimensional manifolds. These equations are closely related to anti self-dual Yang-Mills equations of the infinite dimensional gauge Lie algebras of all volume preserving vector fields. Several examples of hyperk\"ahler metrics are presented through the reductions of anti self-dual connections. For any gauge group anti self-dual connections on hyperk\"ahler manifolds are constructed using the solutions of both Nahm and Laplace equations.Comment: 9pages, Figures are not include

Protein processing characterized by a gel-free proteomics approach

We describe a method for the specific isolation of representative N-terminal peptides of proteins and their proteolytic fragments. Their isolation is based on a gel-free, peptidecentric proteomics approach using the principle of diagonal chromatography. We will indicate that the introduction of an altered chemical property to internal peptides holding a free α-N-terminus results in altered column retention of these peptides, thereby enabling the isolation and further characterization by mass spectrometry of N-terminal peptides. Besides pointing to changes in protein expression levels when performing such proteome surveys in a differential modus, protease specificity and substrate repertoires can be allocated since both are specified by neo-N-termini generated after a protease cleavage event. As such, our gel-free proteomics technology is widely applicable and amenable for a variety of proteome-driven protease degradomics research

Deformation of NaCoF3 perovskite and post-perovskite up to 30 GPa and 1013 K: implications for plastic deformation and transformation mechanism

Texture, plastic deformation, and phase transformation mechanisms in perovskite and post-perovskite are of general interest for our understanding of the Earth's mantle. Here, the perovskite analogue NaCoF3 is deformed in a resistive-heated diamond anvil cell (DAC) up to 30 GPa and 1013 K. The in situ state of the sample, including crystal structure, stress, and texture, is monitored using X-ray diffraction. A phase transformation from a perovskite to a post-perovskite structure is observed between 20.1 and 26.1 GPa. Normalized stress drops by a factor of 3 during transformation as a result of transient weakening during the transformation. The perovskite phase initially develops a texture with a maximum at 100 and a strong 010 minimum in the inverse pole figure of the compression direction. Additionally, a secondary weaker 001 maximum is observed later during compression. Texture simulations indicate that the initial deformation of perovskite requires slip along (100) planes with significant contributions of {110} twins. Following the phase transition to post-perovskite, we observe a 010 maximum, which later evolves with compression. The transformation follows orientation relationships previously suggested where the c axis is preserved between phases and hh0 vectors in reciprocal space of post-perovskite are parallel to [010] in perovskite, which indicates a martensitic-like transition mechanism. A comparison between past experiments on bridgmanite and current results indicates that NaCoF3 is a good analogue to understand the development of microstructures within the Earth's mantle

Anti-self-dual Maxwell solutions on hyperk\"ahler manifold and N=2 supersymmetric Ashtekar gravity

Anti-self-dual (ASD) Maxwell solutions on 4-dimensional hyperk\"ahler manifolds are constructed. The N=2 supersymmetric half-flat equations are derived in the context of the Ashtekar formulation of N=2 supergravity. These equations show that the ASD Maxwell solutions have a direct connection with the solutions of the reduced N=2 supersymmetric ASD Yang-Mills equations with a special choice of gauge group. Two examples of the Maxwell solutions are presented.Comment: 9 page

Biomechanical Simulation of Electrode Migration for Deep Brain Stimulation

International audienceDeep Brain Stimulation is a modern surgical technique for treating patients who suffer from affective or motion disorders such as Parkinson's disease. The efficiency of the procedure relies heavily on the accuracy of the placement of a micro-electrode which sends electrical pulses to a specific part of the brain that controls motion and affective symptoms. However, targeting this small anatomical structure is rendered difficult due to a series of brain shifts that take place during and after the procedure. This paper introduces a biomechanical simulation of the intra and postoperative stages of the procedure in order to determine lead deformation and electrode migration due to brain shift. To achieve this goal, we propose a global approach, which accounts for brain deformation but also for the numerous interactions that take place during the procedure (contacts between the brain and the inner part of the skull and falx cerebri, effect of the cerebro-spinal fluid, and biomechanical interactions between the brain and the electrodes and cannula used during the procedure). Preliminary results show a good correlation between our simulations and various results reported in the literature

Spatialization of climate, physical and socioeconomic factors that affect the dairy goat production in Brazil and their impact on animal breeding decisions.

Abstract: Brazil has high climate, soil and environmental diversity, as well as distinct socioeconomic and political realities, what results in differences among the political administrative regions of the country. The objective of this study was to determine spatial distribution of the physical, climatic and socioeconomic aspects that best characterize the production of dairy goats in Brazil. Production indices of milk per goat, goat production, milk production, as well as temperature range, mean temperature, precipitation, normalized difference vegetation index, relative humidity, altitude, agricultural farms; farms with native pasture, farms with good quality pasture, farms with water resources, farms that receive technical guidance, family farming properties, non-familiar farms and the human development index were evaluated. The multivariate analyses were carried out to spatialize climatic, physical and socioeconomic variables and so differenciate the Brazilian States and Regions. The highest yields of milk and goat production were observed in the Northeast. The Southeast Region had the second highest production of milk, followed by the South, Midwest and North. Multivariate analysis revealed distinctions between clusters of political-administrative regions of Brazil. The climatic variables were most important to discriminate between regions of Brazil. Therefore, it is necessary to implement animal breeding programs to meet the needs of each region. [Espacialização de fatores climáticos, físicos e socioeconômicos que afetam a produção de caprinos leiteiros no Brasil e seu impacto sobre as decisões em melhoramento animal]. Resumo: O Brasil possui diversidade edafoclimática e realidades socioeconômicas e políticas distintas. Isto contribui para diferenciar as regiões político administrativas do país. Objetivou-se espacializar os fatores físicos, climáticos e socioeconômicos que melhor discriminam a produção de caprinos leiteiros no Brasil. Foram analisados índice de produção de leite por cabra; índice de produção de caprinos; índice de produção de leite, amplitude da temperatura; temperatura média; precipitação; índice normalizado de diferença vegetativa; umidade relativa do ar; altitude; estabelecimentos agropecuários; estabelecimentos com pastagem nativa; estabelecimentos com pastagens de boa qualidade; estabelecimentos com recursos hídricos; estabelecimentos que recebem orientação técnica; estabelecimentos de agricultura familiar; estabelecimentos de agricultura não familiar e índice de desenvolvimento humano. Foram realizadas análises multivariadas para espacializar as variáveis climáticas, físicas e socioeconômicas e, assim, discriminar os Estados e Regiões brasileiras. As maiores produções de caprinos e de leite foram observadas na região Nordeste. A região Sudeste apresentou segunda maior produção de leite, seguido pelo Sul, Centro-Oeste e Norte. As médias para produtividade mostraram que as regiões Centro-Oeste e Sudeste apresentaram animais mais especializados a produção de leite. As análises multivariadas evidenciaram distinções entre clusters das regiões político-administrativas do Brasil. As variáveis climáticas foram as mais importantes para discriminar entre as regiões brasileiras. A heterogeneidade dos componentes climáticos, físicos e socioeconômicos evidenciou peculiaridades em cada região. Portanto, é preciso implementar programas de melhoramento genético animal que atendam as necessidades de cada região

Seleção de tamanho de partículas por bovinos Nelore em confinamento e sua relação com características de carcaça.

Pesquisas apresentam a existência de variação individual em relação ao comportamento alimentar de bovinos confinados, mesmo estando na mesma baia de confinamento. Objetivou-se avaliar se a seletividade por tamanho de partícula no cocho tem relação com as características de carcaça de bovinos Nelore Mocho. O experimento foi realizado na área de confinamento de junho a novembro de 2012. Foram utilizados 18 animais, com idade e peso médio iniciais de 21 meses e 335 kg, respectivamente, provenientes do rebanho da marca OB. Os animais foram abatidos com idade e o peso médio de 23 meses e 535 kg, e espessura de gordura mínima de 5 mm. Foi mantido um registro diário do ofertado e das sobras recolhidas, por animal. Avaliou-se o tamanho médio de partículas restantes no cocho pelo método Penn State a cada quatro horas diárias. Fez-se uso de análises de Cluster para agrupar os animais conforme seletividade por partículas consumidas. As médias foram ajustadas pelo método dos mínimos quadrados e comparadas por meio do teste de Tukey a 5% de probabilidade. Apesar do comportamento seletivo diferenciado, em relação ao tamanho de partículas, não houve diferença estatística significativa entre os grupos de seleção alimentar (p>0,05) para as características de carcaça dos animais. Conclui-se que a seletividade por tamanho de partículas no cocho não implicam em alterações nas características de carcaça de bovinos de corte em confinamento. Abstract: Studies with feedlot livestock have identified quantitative and qualitative differences as it relates to individual food intake. The objective of this study was to evaluate if the food selection based on particle size in the trough was associated carcass characteristics of Nelore Mocho cattle. The experiment was conducted in the confinement, from June to November 2012. Eighteen OB brand animals were studied, with respective baseline age and average weight of 21 months and 335 kg. The animals were slaughtered at an average age and weight of 23 months and 515 kg, and minimal subcutaneous thickness of 5 mm. A registry of the daily intake was kept. The Penn State method and leftover scores were used to analyze the average size of the particles at four hour a day of feeding. Cluster analysis was used to group animals according to particle size selectivity for food intake. Least square method was used to adjust averages and Tukey?s test was used for comparison at 5% probability level. Despite the different selective behavior related to particle sizes, there were no statistically significant differences (p>0.05) among carcass characteristics. It was concluded particle size selectivity not affect carcass characteristics of confined beef cattle

Seleção de tamanho de partículas por bovinos Nelore Mocho e sua relação com o desempenho animal em confinamento.

Em estudos com animais de produção em confinamento são verificadas diferenças individuais em relação ao consumo alimentar, tanto em quantidade como qualidade, entretanto, pouco se sabe da influencia da seleção no desempenho. Assim, objetivou-se avaliar se a seletividade por tamanho de partícula no cocho tem relação com o desempenho de bovinos Nelore Mocho. O experimento foi realizado na área de confinamento de junho a novembro de 2012. Foram utilizados 18 animais, com idade e peso médio iniciais de 21 meses e 335 kg, respectivamente, provenientes do rebanho da marca OB. Os animais foram abatidos com idade e o peso médio de 23 meses e 535 kg, e espessura de gordura mínima de 5 mm. Foi mantido um registro diário do ofertado e das sobras recolhidas, por animal. Avaliou-se o tamanho médio de partículas restantes no cocho pelo método Penn State a cada quatro horas diárias. Fez-se uso de análises de Cluster para agrupar os animais conforme seletividade por partículas consumidas. As médias foram ajustadas pelo método dos mínimos quadrados e comparadas por meio do teste de Tukey a 5% de probabilidade. Apesar do comportamento seletivo diferenciado, em relação ao tamanho de partículas, não houve diferença estatisticamente significativa entre os grupos de seleção alimentar (p>0,05) para as características de desempenho dos animais. Conclui-se que a seletividade por tamanho de partículas no cocho não implicam em alterações no desempenho de bovinos de corte em confinamento. Abstract: Studies with feedlot livestock have identified quantitative and qualitative differences as it relates to individual food intake. The objective of this study was to evaluate if the food selection based on particle size in the trough was associated with the performance of Polled Nelore cattle. The experiment was conducted in the confinement, from June to November 2012. Eighteen OB brand animals were studied, with respective baseline age and average weight of 21 months and 335 kg. The animals were slaughtered at an average age and weight of 23 months and 535 kg, and minimal subcutaneous thickness of 5 mm. A registry of the daily intake was kept. The Penn State method and leftover scores were used to analyze the average size of the particles at four hour a day of feeding. Cluster analysis was used to group animals according to particle size selectivity for food intake. Least square method was used to adjust averages and Tukey?s test was used for comparison at 5% probability level. Despite the different selective behavior related to particle sizes, there were no statistically significant differences (p>0.05) among all animal performance characteristics. It was concluded particle size selectivity not affect performance variables of confined beef cattle

Multiple factor analysis to identify correlated variable among microclimate, thermal comfort and infrared thermography in agroforestry systems.

Goal was to use the Multiple Factor Analysis to reduce dimensionality of variables, to identify groups of correlated variables and to obtain a common assessment tool to evaluate microclimate, thermal comfort and infrared thermography in agroforestry systems. The experiment was conducted at the Embrapa Beef Cattle, Campo Grande, MS, from July 2015 to February 2016, corresponding to winter and summer seasons, in two agroforestry systems with different tree densities and spatial arrangements of native and planted trees. Readings were made from 8:00 a.m. to 4:00 p.m., for microclimate parameters (air temperature, dew point temperature, black globe temperature, relative humidity, wind speed, global solar radiation, photosynthetically active radiation and luminosity), thermal comfort (Temperature and Humidity Index, Black Globe and Humidity Index, Radiation Thermal Load), and infrared thermography (temperature and humidity of tree crown and soil surface), under full sun and shadow projection. Multiple Factor Analysis found three Synthetic Analytical Dimensions that explained 55.5% of the total observed variance. Strong and positive associations between infrared thermography, microclimate, thermal comfort and radiation were found. Thus, it is suggested that infrared thermography is a potential tool to be used for microclimate prediction and thermal comfort under agroforestry systems