Multi-Nozzle Biopolymer Deposition for Freeform Fabrication of Tissue Constructs

Advanced freeform fabrication techniques have been recently used for the construction of tissue scaffolds because of the process repeatability and capability of high accuracy in fabrication resolution at the macro and micro scales. Among many applicable tissue scaffolding materials, polymeric materials have unique properties in terms of the biocompatibility and degradation, and have thus been widely utilized in tissue engineering applications. Hydrogels, such as alginate, has been one of the most important polymer scaffolding materials because of its biocompatibility and internal structure similarity to that of the extracellular matrix of many tissues, and its relatively moderate processing. Three-dimensional deposition has been an entreating freeform fabrication method of biopolymer and particularly hydrogel scaffolds because of its readiness to deposit fluids at ambient temperatures. This paper presents a recent development of biopolymer deposition based freeform fabrication for 3-diemnsinal tissue scaffolds. The system configuration of multi-nozzles used in the deposition of sodium alginate solutions and Poly-?- Caprolactone (PCL) are described. Studies on polymer deposition feasibility and structural formability are conducted, and the preliminary results are presented.Mechanical Engineerin

Seevolution: visualizing chromosome evolution

Summary: Genome evolution underpins all of biology, yet its principles can be difficult to communicate to the non-specialist. To facilitate broader understanding of genome evolution, we have designed an interactive 3D environment that enables visualization of diverse genome evolution processes. The system can intuitively and interactively animate mutation histories involving genome rearrangement, point mutation, recombination, insertion and deletion. Multiple organisms related by a phylogeny can be visualized simultaneously. As methods to infer evolutionary histories of genomes become increasingly complex, visualization of the evolutionary process will not only be useful for communication, but will also serve as an exploratory tool for discovering new patterns of genome evolution

On the X-ray Properties of OH Megamaser Sources: Chandra Snapshot Observations

We present Chandra snapshot observations for a sample of 7 sources selected from the Arecibo OH megamaser (OHM) survey at z~0.13-0.22 and with far-infrared luminosities in excess of 10^{11} L_sun. In contrast with the known H2O megamasers, which are mostly associated with powerful Active Galactic Nuclei (AGN), the situation is far less clear for OHMs, which have been poorly studied in the X-ray band thus far. All of the observed sources are X-ray weak, with only one OHM, IRAS FSC 03521+0028 (z=0.15), being detected by Chandra (with 5 counts). The results from this pilot program indicate that the X-ray emission, with luminosities of less than ~10^{42} erg/s, is consistent with that from star formation (as also suggested in some cases by the optical spectra) and low-luminosity AGN emission. If an AGN is present, its contribution to the broad-band emission of OHM galaxies is likely modest. Under reasonable assumptions about the intrinsic X-ray spectral shape, the observed count distribution from stacking analysis suggests absorption of ~10^{22} cm^{-2}.Comment: 8 pages, 3 figures, accepted for publication in MNRA

Exploring Factors of Non-Compliance for Adolescents with Celiac Disease

Individuals with celiac disease face many challenges when navigating the world around them. Adolescents with celiac disease must face the challenge of standing out in a world that is heavily influenced by peers and the pressure to fit in. The purpose of this project was to explore factors of non-compliance for adolescents with celiac disease. Using a qualitative design, two adolescent female volunteers participated in a focus group regarding factors in their lives that led them to not comply with the gluten-free diet. Data were analyzed and the focus group responses were then linked to previous related literature. The findings indicated that the respondents were in fact able to comply with the gluten-free diet based on the severity of their symptoms, support from others, knowledge of others about the gluten-free diet, and their own knowledge. These findings highlight the importance of support and knowledge and point out the need for a greater effort to offer continued support and research for celiac disease

Children\u27s Awareness of Environmental Pollution

The purpose of this study was to determine children\u27s awareness of environmental pollution and the effect of environmental education on the awareness of preschool children. Data for this study were collected by individually interviewing 20 preschool, 20 first grade and 20 third grade children. These 60 children were presented 15 colored slides and 9 words denoting various types of pollution and environmental symbols and slogans. The slides varied from litter on a beach, chimneys emitting black smoke, and polluted water to such environmental symbols as Smokey Bear, Johnny Horizon, and Woodsy Owl. In addition, the environmental symbols were also presented verbally, accompanied by such words as litter, pollution, and ecology. The children\u27s responses were evaluated and used to indicate the effect of age and sex upon children\u27s awareness, the relationship between children\u27s responses to pictorial and verbal stimuli, and the effects of an environmental education program on the awareness of preschool children. The findings of this study indicate that there are differences in awareness of environmental pollution between different ages of children, but not between males and females. As children become older, there is both an increasing awareness of environmental pollution and an increasing correlation between the recognition of visual and verbal stimuli. An environmental education unit was also found to influence the environmental awareness of preschool children. While the experimental group, which was involved in an environmental education unit showed significant increases in environmental awareness, the control group did not