Senior Recital:Ivory Sebastion, Clarinet

Kemp Recital Hall Friday Evening March 19, 2004 6:00p.m

Environmental technology development through industry partnership

The Coherent Laser Vision System (CLVS) is being developed to provide precision real-time 3D world views to support site characterization and robotic operations and during facilities Decontamination and Decommissioning. Autonomous or semiautonomous robotic operations requires an accurate, up-to-date 3D world view. Existing technologies for real-time 3D imaging, such as AM laser radar, have limited accuracy at significant ranges and have variability in range estimates caused by lighting or surface shading. Recent advances in fiber optic component technology and digital processing components have enabled the development of a new 3D vision system based upon a fiber optic FMCW coherent laser radar. The approach includes a compact scanner with no-moving parts capable of randomly addressing all pixels. The system maintains the immunity to lighting and surface shading conditions which is characteristic to coherent laser radar. The random pixel addressability allows concentration of scanning and processing on the active areas of a scene, as is done by the human eye-brain system. The precision measurement capability of the coherent laser radar (CLR) technology has already been demonstrated in the form of the CLR 3D Mapper, of which several copies have been delivered or are under order. The CLVS system, in contrast to the CLR 3D Mapper, will have substantially greater imaging speed with a compact no-moving parts scanner, more suitable for real-time robotic operations

SAVER: Surface Autonomous Vehicle for Emergency Rescue

The design, fabrication, and testing of an unmanned surface vehicle for the NASA Micro-G NExT SAVER challenge. This device features a radio direction finding phase array to autonomously navigate to an emergency distress beacon to deliver emergency supplies

Fem Kvinnor

Kemp Recital Hall Wednesday Evening March 31, 2004 6:00p.m

Evolutionary Interactions between N-Linked Glycosylation Sites in the HIV-1 Envelope

The addition of asparagine (N)-linked polysaccharide chains (i.e., glycans) to the gp120 and gp41 glycoproteins of human immunodeficiency virus type 1 (HIV-1) envelope is not only required for correct protein folding, but also may provide protection against neutralizing antibodies as a “glycan shield.” As a result, strong host-specific selection is frequently associated with codon positions where nonsynonymous substitutions can create or disrupt potential N-linked glycosylation sites (PNGSs). Moreover, empirical data suggest that the individual contribution of PNGSs to the neutralization sensitivity or infectivity of HIV-1 may be critically dependent on the presence or absence of other PNGSs in the envelope sequence. Here we evaluate how glycan–glycan interactions have shaped the evolution of HIV-1 envelope sequences by analyzing the distribution of PNGSs in a large-sequence alignment. Using a “covarion”-type phylogenetic model, we find that the rates at which individual PNGSs are gained or lost vary significantly over time, suggesting that the selective advantage of having a PNGS may depend on the presence or absence of other PNGSs in the sequence. Consequently, we identify specific interactions between PNGSs in the alignment using a new paired-character phylogenetic model of evolution, and a Bayesian graphical model. Despite the fundamental differences between these two methods, several interactions are jointly identified by both. Mapping these interactions onto a structural model of HIV-1 gp120 reveals that negative (exclusive) interactions occur significantly more often between colocalized glycans, while positive (inclusive) interactions are restricted to more distant glycans. Our results imply that the adaptive repertoire of alternative configurations in the HIV-1 glycan shield is limited by functional interactions between the N-linked glycans. This represents a potential vulnerability of rapidly evolving HIV-1 populations that may provide useful glycan-based targets for neutralizing antibodies

Coping with Viral Diversity in HIV Vaccine Design

The ability of human immunodeficiency virus type 1 (HIV-1) to develop high levels of genetic diversity, and thereby acquire mutations to escape immune pressures, contributes to the difficulties in producing a vaccine. Possibly no single HIV-1 sequence can induce sufficiently broad immunity to protect against a wide variety of infectious strains, or block mutational escape pathways available to the virus after infection. The authors describe the generation of HIV-1 immunogens that minimizes the phylogenetic distance of viral strains throughout the known viral population (the center of tree [COT]) and then extend the COT immunogen by addition of a composite sequence that includes high-frequency variable sites preserved in their native contexts. The resulting COT(+) antigens compress the variation found in many independent HIV-1 isolates into lengths suitable for vaccine immunogens. It is possible to capture 62% of the variation found in the Nef protein and 82% of the variation in the Gag protein into immunogens of three gene lengths. The authors put forward immunogen designs that maximize representation of the diverse antigenic features present in a spectrum of HIV-1 strains. These immunogens should elicit immune responses against high-frequency viral strains as well as against most mutant forms of the virus

Dieta low-carb no período perinatal de ratas sobre a preferência por bebida açucarada, consumo alimentar e peso corporal em prole de macho / Low-carb diet in perinatal rats on sugar-sweetened beverage preference, food consumption and body weight in male offspring

A busca por meios de estilos de vida mais saudáveis vem expandindo-se gradativamente. Em meio às inúmeras intervenções nutricionais destaca-se a dieta com baixo teor de carboidratos. Quando aplicada no período perinatal, essa dieta pode acarretar alterações no desenvolvimento do organismo, além de exercer influência na formação dos hábitos e preferências alimentares. Avaliar os efeitos da dieta low carb durante o período perinatal de ratas sobre os padrões de crescimento e maturação das características físicas da prole e sobre a preferência por bebida açucarada, consumo alimentar. Foram utilizadas 12 ratas albinas da linhagem Wistar e os machos de suas proles. Os animais foram divididos em dois grupos conforme dieta ofertada no período perinatal: Grupo Controle (C - alimentado com ração padrão, n=8), e Grupo low carb (LC - alimentado com ração com baixo teor de carboidratos, n=4). Foi quantificado peso gestacional e lactacional semanal, e consumo alimentar semanal das ratas. Após 24h do nascimento dos animais foi determinado o peso ao nascer da prole: Peso da ninhada/número dos filhotes. Os procedimentos de pesagem medidas murinómetricas foram realizados em dias ímpares, até o desmame. As medidas murinométricas tomadas foram: peso corporal, eixo longitudinal (EL), comprimento da cauda (CC), e eixos latero-lateral (ELLC) e ântero-posterior do crânio (EAPC). Foi mensurado, também, o desenvolvimento de características físicas como: abertura dos olhos, erupção dos incisivos inferiores e superiores e abertura do pavilhão auditivo. Após o desmame, os filhotes foram submetidos a dois testes de preferência com refrigerantes energético e não energético aos 30 e 60 dias de vida; também nestas idades foram avaliados: peso corporal, consumo alimentar e ingestão hídrica. Aos 70 dias, os filhotes foram sacrificados e foi feita a pesagem dos órgãos. Para análise estatística foram utilizados os testes “T” de Student’s considerando a significância p<0,05. As ratas durante a gestação e lactação não apresentam diferença no consumo e peso corporal. A prole macho do GLC apresentou maior peso corporal no 21º dia de vida. Foi observado maior ELLC nos 3º, 5º e 15º dias na prole do GLC. Quanto ao desenvolvimento de características físicas, foi evidenciado o adiantamento da erupção dos incisivos inferiores nos machos e superiores nas fêmeas. O LC apresentou menor peso corporal aos 60 dias, e menor percentual de ganho de peso aos 30 dias, mas maior aos 60 dias. Esses dados acabam nos remetendo à plasticidade fenotípica e ao efeito catch up, de modo que o organismo dos animais tenha se adaptado à demanda de nutrientes no período perinatal e aos mecanismos fisiológicos consecutivos a essa demanda, e que esses mecanismos tenham permanecido e influenciado nos parâmetros de crescimento e atraso no pico de crescimento (MUNIZ, 2013; LIMA, 2015). LC consumiu mais água em ambos os testes, maior quantidade de coca-cola zero no primeiro teste, assim como mais ração durante o segundo teste, o que acarretou um maior consumo energético também no segundo teste; O LC consumiu menos coca-cola aos 30 dias, já aos 60 dias não houve diferença entre os grupos. As bebidas carbonatadas adoçadas artificialmente possuem o dobro de sódio das bebidas carbonatadas açucaradas (FERRARI e SOARES, 2003), e esse maior aporte de sódio pelos animais geraria um maior apetite pelo aumento dos hormônios glicorticóides (SOUZA, 2018). Estudos em ratos demonstram que a privação rigorosa de carboidratos, durante o período perinatal gera menor sensibilidade aos mesmos (GRECO, 2017; LAUREANEO, 2013). Aos 60 dias a não diferença no consumo de refrigerante foi influenciado pela experiência e consequente habituação do paladar ao açúcar/carboidrato. Os pesos úmidos do coração e baço apresentaram-se menores no GLC, já o peso relativo da gordura visceral foi maior no GLC. A dieta low carb aplicada na gestação e lactação influencia no crescimento e desenvolvimento de características físicas na prole, assim como exerce influência na formação dos hábitos alimentares por diminuir a preferência por açúcar/carboidrato

Antisolvent crystallisation in oscillatory baffled platforms

Continuous manufacturing finds application in a variety of disciplines. It demonstrates a number of advantages, such as more controllable processes and allows particle attributes to be attained that would otherwise be unattainable. Antisolvent crystallisation is a widely used method of crystallisation in both academia and industry. It is employed to crystallise compounds that are not amenable to other techniques such as cooling crystallisation and can be utilised to produce crystal products with unique properties.;Oscillatory baffled crystallisers (OBCs) are platforms that generate intense mixing by the oscillatory motion of fluid through periodic constrictions, referred to as baffles. The oscillatory motion generates eddy currents through these baffles and induce highly turbulent and efficient mixing. By the superimposition of a net flow, the process can operate at near plug-flow conditions and is the principle of the continuous oscillatory baffled crystalliser (COBC). OBCs have been extensively studied for cooling crystallisations, but their application in antisolvent crystallisation has been limited.;The continuous antisolvent crystallisation of anthranilic acid in a COBC has been investigated for the first time as a function of antisolvent volume fraction and flow conditions, demonstrating the effects of a number of process variables on product outcomes. Metastable form II polymorph of anthranilic acid was consistently produced in a continuous unseeded antisolvent crystallisation from an ethanol and water solvent system.;The incorporation of process analytical technology (PAT) allowed for monitoring of various process conditions in real time, giving insight into the evolution of the antisolvent crystallisation process in continuous flow. Local mixing effects were deemed to be significant in the COBC at the point of contact of solution and antisolvent, such that variable flow rates at fixed antisolvent compositions resulted in different product sizes whilst resulting in the same final solution concentration.;Polymorph control in a moving baffle oscillatory baffled crystalliser (MBOBC) was demonstrated for the anthranilic acid system. By variation of seeding conditions and startup strategy, the continuous production of either stable form I or metastable form II polymorph could be controlled. This demonstrated a novel continuous nucleation platform for an antisolvent crystallisation process that could potentially be coupled with a COBC or other platform for reliable continuous production of a specified polymorph with targeted crystal attributes.;Growth and secondary nucleation kinetic parameters were determined by means of isothermal seeded batch experiments in a batch moving fluid oscillatory baffled crystalliser (MFOBC). Models were developed from these determined parameters, and further refined by the incorporation of a solvent factor that improved the fit of the model predictions to the experimentally measured attributes. The determined parameters were applied to the optimisation of a 30 m DN15 COBC with multiple antisolvent addition points and demonstrates the first such strategy utilising experimentally determined kinetic parameters.;This work has demonstrated novel approaches for the development of antisolvent crystallisation processes in continuous flow in oscillatory baffled crystallisers, detailing a number of control strategies and advancing the knowledge and understanding of such processes for future implementation.Continuous manufacturing finds application in a variety of disciplines. It demonstrates a number of advantages, such as more controllable processes and allows particle attributes to be attained that would otherwise be unattainable. Antisolvent crystallisation is a widely used method of crystallisation in both academia and industry. It is employed to crystallise compounds that are not amenable to other techniques such as cooling crystallisation and can be utilised to produce crystal products with unique properties.;Oscillatory baffled crystallisers (OBCs) are platforms that generate intense mixing by the oscillatory motion of fluid through periodic constrictions, referred to as baffles. The oscillatory motion generates eddy currents through these baffles and induce highly turbulent and efficient mixing. By the superimposition of a net flow, the process can operate at near plug-flow conditions and is the principle of the continuous oscillatory baffled crystalliser (COBC). OBCs have been extensively studied for cooling crystallisations, but their application in antisolvent crystallisation has been limited.;The continuous antisolvent crystallisation of anthranilic acid in a COBC has been investigated for the first time as a function of antisolvent volume fraction and flow conditions, demonstrating the effects of a number of process variables on product outcomes. Metastable form II polymorph of anthranilic acid was consistently produced in a continuous unseeded antisolvent crystallisation from an ethanol and water solvent system.;The incorporation of process analytical technology (PAT) allowed for monitoring of various process conditions in real time, giving insight into the evolution of the antisolvent crystallisation process in continuous flow. Local mixing effects were deemed to be significant in the COBC at the point of contact of solution and antisolvent, such that variable flow rates at fixed antisolvent compositions resulted in different product sizes whilst resulting in the same final solution concentration.;Polymorph control in a moving baffle oscillatory baffled crystalliser (MBOBC) was demonstrated for the anthranilic acid system. By variation of seeding conditions and startup strategy, the continuous production of either stable form I or metastable form II polymorph could be controlled. This demonstrated a novel continuous nucleation platform for an antisolvent crystallisation process that could potentially be coupled with a COBC or other platform for reliable continuous production of a specified polymorph with targeted crystal attributes.;Growth and secondary nucleation kinetic parameters were determined by means of isothermal seeded batch experiments in a batch moving fluid oscillatory baffled crystalliser (MFOBC). Models were developed from these determined parameters, and further refined by the incorporation of a solvent factor that improved the fit of the model predictions to the experimentally measured attributes. The determined parameters were applied to the optimisation of a 30 m DN15 COBC with multiple antisolvent addition points and demonstrates the first such strategy utilising experimentally determined kinetic parameters.;This work has demonstrated novel approaches for the development of antisolvent crystallisation processes in continuous flow in oscillatory baffled crystallisers, detailing a number of control strategies and advancing the knowledge and understanding of such processes for future implementation