Matching Items (206)
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Many children born preterm exhibit frontal executive dysfunction, behavioral problems including attentional deficit/hyperactivity disorder and attention related learning disabilities. Anomalies in regional specificity of cortico-striato-thalamo-cortical circuits may underlie deficits in these disorders. Nonspecific volumetric deficits of striatal structures have been documented in these subjects, but little is known about surface

Many children born preterm exhibit frontal executive dysfunction, behavioral problems including attentional deficit/hyperactivity disorder and attention related learning disabilities. Anomalies in regional specificity of cortico-striato-thalamo-cortical circuits may underlie deficits in these disorders. Nonspecific volumetric deficits of striatal structures have been documented in these subjects, but little is known about surface deformation in these structures. For the first time, here we found regional surface morphological differences in the preterm neonatal ventral striatum. We performed regional group comparisons of the surface anatomy of the striatum (putamen and globus pallidus) between 17 preterm and 19 term-born neonates at term-equivalent age. We reconstructed striatal surfaces from manually segmented brain magnetic resonance images and analyzed them using our in-house conformal mapping program. All surfaces were registered to a template with a new surface fluid registration method. Vertex-based statistical comparisons between the two groups were performed via four methods: univariate and multivariate tensor-based morphometry, the commonly used medial axis distance, and a combination of the last two statistics. We found statistically significant differences in regional morphology between the two groups that are consistent across statistics, but more extensive for multivariate measures. Differences were localized to the ventral aspect of the striatum. In particular, we found abnormalities in the preterm anterior/inferior putamen, which is interconnected with the medial orbital/prefrontal cortex and the midline thalamic nuclei including the medial dorsal nucleus and pulvinar. These findings support the hypothesis that the ventral striatum is vulnerable, within the cortico-stiato-thalamo-cortical neural circuitry, which may underlie the risk for long-term development of frontal executive dysfunction, attention deficit hyperactivity disorder and attention-related learning disabilities in preterm neonates.

ContributorsShi, Jie (Author) / Wang, Yalin (Author) / Ceschin, Rafael (Author) / An, Xing (Author) / Lao, Yi (Author) / Vanderbilt, Douglas (Author) / Nelson, Marvin D. (Author) / Thompson, Paul M. (Author) / Panigrahy, Ashok (Author) / Lepore, Natasha (Author) / Ira A. Fulton Schools of Engineering (Contributor)
Created2013-07-03
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Recent advances in nonequilibrium statistical physics have provided unprecedented insight into the thermodynamics of dynamic processes. The author recently used these advances to extend Landauer’s semi-formal reasoning concerning the thermodynamics of bit erasure, to derive the minimal free energy required to implement an arbitrary computation. Here, I extend this analysis,

Recent advances in nonequilibrium statistical physics have provided unprecedented insight into the thermodynamics of dynamic processes. The author recently used these advances to extend Landauer’s semi-formal reasoning concerning the thermodynamics of bit erasure, to derive the minimal free energy required to implement an arbitrary computation. Here, I extend this analysis, deriving the minimal free energy required by an organism to run a given (stochastic) map π from its sensor inputs to its actuator outputs. I use this result to calculate the input-output map π of an organism that optimally trades off the free energy needed to run π with the phenotypic fitness that results from implementing π. I end with a general discussion of the limits imposed on the rate of the terrestrial biosphere’s information processing by the flux of sunlight on the Earth.

Created2016-04-13
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Description

Streptococcus pneumoniae still causes severe morbidity and mortality worldwide, especially in young children and the elderly. Much effort has been dedicated to developing protein-based universal vaccines to conquer the current shortcomings of capsular vaccines and capsular conjugate vaccines, such as serotype replacement, limited coverage and high costs. A recombinant live

Streptococcus pneumoniae still causes severe morbidity and mortality worldwide, especially in young children and the elderly. Much effort has been dedicated to developing protein-based universal vaccines to conquer the current shortcomings of capsular vaccines and capsular conjugate vaccines, such as serotype replacement, limited coverage and high costs. A recombinant live vector vaccine delivering protective antigens is a promising way to achieve this goal. In this review, we discuss the researches using live recombinant vaccines, mainly live attenuated Salmonella and lactic acid bacteria, to deliver pneumococcal antigens. We also discuss both the limitations and the future of these vaccines.

Created2015-01-07
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High proportions of autistic children suffer from gastrointestinal (GI) disorders, implying a link between autism and abnormalities in gut microbial functions. Increasing evidence from recent high-throughput sequencing analyses indicates that disturbances in composition and diversity of gut microbiome are associated with various disease conditions. However, microbiome-level studies on autism are

High proportions of autistic children suffer from gastrointestinal (GI) disorders, implying a link between autism and abnormalities in gut microbial functions. Increasing evidence from recent high-throughput sequencing analyses indicates that disturbances in composition and diversity of gut microbiome are associated with various disease conditions. However, microbiome-level studies on autism are limited and mostly focused on pathogenic bacteria. Therefore, here we aimed to define systemic changes in gut microbiome associated with autism and autism-related GI problems. We recruited 20 neurotypical and 20 autistic children accompanied by a survey of both autistic severity and GI symptoms. By pyrosequencing the V2/V3 regions in bacterial 16S rDNA from fecal DNA samples, we compared gut microbiomes of GI symptom-free neurotypical children with those of autistic children mostly presenting GI symptoms. Unexpectedly, the presence of autistic symptoms, rather than the severity of GI symptoms, was associated with less diverse gut microbiomes. Further, rigorous statistical tests with multiple testing corrections showed significantly lower abundances of the genera Prevotella, Coprococcus, and unclassified Veillonellaceae in autistic samples. These are intriguingly versatile carbohydrate-degrading and/or fermenting bacteria, suggesting a potential influence of unusual diet patterns observed in autistic children. However, multivariate analyses showed that autism-related changes in both overall diversity and individual genus abundances were correlated with the presence of autistic symptoms but not with their diet patterns. Taken together, autism and accompanying GI symptoms were characterized by distinct and less diverse gut microbial compositions with lower levels of Prevotella, Coprococcus, and unclassified Veillonellaceae.

ContributorsKang, Dae Wook (Author) / Park, Jin (Author) / Ilhan, Zehra (Author) / Wallstrom, Garrick (Author) / LaBaer, Joshua (Author) / Adams, James (Author) / Krajmalnik-Brown, Rosa (Author) / Biodesign Institute (Contributor)
Created2013-06-03
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Description
Freshwater is an essential component of life for most organisms on earth. "Civilization itself is built on a foundation of water (Fagan, 2011)," as people often congregate near water sources, and find innovative solutions to exploit these resources for food production and domestic needs. Rising demand for water due to

Freshwater is an essential component of life for most organisms on earth. "Civilization itself is built on a foundation of water (Fagan, 2011)," as people often congregate near water sources, and find innovative solutions to exploit these resources for food production and domestic needs. Rising demand for water due to altered lifestyles and population increase pose further stress on water availability. Alterations and pollution of freshwater ecosystems can dramatically compromise ecological services that many species, among them humans, depend on. Arid places are specifically vulnerable in regards to water, characterized by very low levels of precipitation, as well as many dry months, which are often followed by a short time of severe storms. Considering the interconnectedness of social and ecological systems in regards to freshwater services is crucial in order to sustainably manage freshwater resources and avoid ecological crises that in turn are likely to lead to social crises around the globe (Berkes et. al., 2003).
ContributorsHenenson, Einav (Author) / Anderies, M. John (Thesis director) / Aggarwal, Rimjhim (Committee member) / Golub, Aaron (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor)
Created2012-12
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Description
The purpose of my honors thesis project was to generate the tools needed for in vivo imaging by determining the optimal plasmid-fluorophore combination. To determine the optimal plasmid and fluorophore, asd plasmids were constructed with various promoters, origins of replications, and red fluorophores. The optimal asd plasmid for fluorescent in

The purpose of my honors thesis project was to generate the tools needed for in vivo imaging by determining the optimal plasmid-fluorophore combination. To determine the optimal plasmid and fluorophore, asd plasmids were constructed with various promoters, origins of replications, and red fluorophores. The optimal asd plasmid for fluorescent in vivo imaging was determined by the plasmid stability, growth rate, and growth phase dependence on fluorescent intensity. The end goal is to be able to use the asd plasmid in vaccine strains for the purpose of in vivo imaging of the recombinant attenuated Salmonella vaccine (RASV).
ContributorsEudy, L. Adam (Author) / Curtiss, Roy (Thesis director) / Roland, Kenneth (Committee member) / Forbes, Stephen (Committee member) / Barrett, The Honors College (Contributor) / College of Liberal Arts and Sciences (Contributor)
Created2012-12