Public space and well-being: an empirical study of Central Park in Old Louisville.

Urban green spaces have been receiving attention in urban planning and the health profession in the 21st century as environmental elements that contribute to well-being. This dissertation explored the relationship between green space usage and individuals’ physical, mental, and social well-being. This empirical research focused on Central Park in Old Louisville to examine how residents use the park and whether it contributes to the well-being of residents. After exploring the existing literature, I identified four well-being indices: (1) perceived health (PHI), (2) health outcome (HOI), (3) mental well-being (MWI), and (4) social well-being (SWI). Frequent Park usage is expected to positively impact these measures. The survey questionnaires were distributed to all residential units (single and multi-family houses, apartments, and senior housing) in the study area. This survey collected information regarding individuals’ park usage patterns, activities, physical, mental, and social well-being status, and socioeconomic characteristics. The multi-linear regression results showed that frequent park usage has positive but insignificant, impacts on participants’ physical, mental, and social well-being. Implementing interaction terms to assess the impact of frequent park usage on well-being measures, did not improve the results, either. However, using Central Park for socializing and attending social events contributes significantly to individuals’ social well-being. The log-linear regression models revealed consistent positive impacts of frequent park usage for social events on residents’ social well-being. Further, one of the log-linear models (Model 3) also uncovered positive and significant (at the 5% significant level) impacts on the health outcome index. The results of both models suggest that gender, age, and income played statistically significant roles in promoting respondents’ general health, health outcomes, mental and social well-being

ATR protects the genome against CGG·CCG-repeat expansion in Fragile X premutation mice

Fragile X mental retardation syndrome is a repeat expansion disease caused by expansion of a CGG·CCG-repeat tract in the 5′ UTR of the FMR1 gene. In humans, small expansions occur more frequently on paternal transmission while large expansions are exclusively maternal in origin. It has been suggested that expansion is the result of aberrant DNA replication, repair or recombination. To distinguish amongst these possibilities we crossed mice containing 120 CGG·CCG-repeats in the 5′ UTR of the mouse Fmr1 gene to mice with mutations in ATR, a protein important in the cellular response to stalled replication forks and bulky DNA lesions. We show here that ATR heterozygosity results in increased expansion rates of maternally, but not paternally, transmitted alleles. In addition, age-related somatic expansions occurred in mice of both genders that were not seen in ATR wild-type animals. Some ATR-sensitive expansion occurs in postmitotic cells including haploid gametes suggesting that aberrant DNA repair is responsible. Our data suggest that two mechanisms of repeat expansion exist that may explain the small and large expansions seen in humans. In addition, our data provide an explanation for the maternal bias of large expansions in humans and the lower incidence of these expansions in mice

Utopia in Kurt Vonnegut's Cat's Cradle

Utopia is a universal concept, as manifested by the fact that it has attracted readers of five centuries and has influenced numerous writers. It is obvious that people, recognizing the abundant stupidities, corruptions, and injustice prevalent in their society, should attempt to plan a better system for living together. Whether they can reach such a society or not is the fundamental question found in most Vonnegut’s works. The utopian schemes in Vonnegut’s works such as the settlement of San Lorenzo in Cat's Cradle, almost always backfire, often bringing about more problems than they promise to solve. Therefore, in this paper, it is aimed to emphasize Vonnegut's Cat's Cradle regarding the concepts of utopia and dystopia as well as apocalyptical notions. Apocalypse can be investigated in Cat’s Cradle and it gives a serious quality to Vonnegut's work. The emptiness of mere survival is painfully described in Cat's Cradle, in which the earth is locked in frozen death

Predicting the future of atomic clocks using the Theory of Evolution

Thesis (S.M.)--Massachusetts Institute of Technology, System Design and Management Program, 2008.Includes bibliographical references (leaves 59-60).The trend of technology evolution plays a very important role to understand how and why products evolve over time and define strategies of further improvements of products. The trend of evolution is based on the fact that all the products, process or technical systems will evolve over time. A cesium atomic clock is the most accurate realization of a reference unit that mankind has yet achieved. The commercial cesium atomic clock is very mature and the demand for this type of clocks expected to be flat. A size reduction is possible due to new physics improvement by using optical pumping technique, but no major changes in performance and prices are expected. The masers outperform the high performance cesium clocks for a time period of sub seconds to one day. The hydrogen maser is very mature product like cesium and the design has remained the same for the last 30 years. The product is expected to remain as presently available. Rubidium atomic clocks provide enhanced accuracy, stability and timing precision compared to quartz-based technologies. This market is large enough to support continuing technological innovation. The world's first commercially available miniature developed by Symmetricom in 2008 marks a major step toward in the evolution of rubidium atomic clocks. It is predicted that future of rubidium oscillators will be based on coherent population trapping technology. The miniature rubidium clocks will be smaller, cheaper, and will be operated by small batteries.by Ben Entezam.S.M

Electron beam irradiation method to change polypropylene application: Rheology and thermomechanical properties

Irradiation of polymers is one of the most effective and economical methods for modifying their properties and for changing their applications. In this study, an extrusion grade polypropylene (PP) was treated by electron beam irradiation to produce a PP suitable for injection molding. Irradiation was carried out at different doses (0-80 kGy) under atmosphere air and at ambient temperature. Melt flow index (MFI) measurements showed PP samples irradiated in the range of 10 to 40 kGy are suitable to use in injection molding. Electron beam irradiation decreased the viscosity and the shear thinning rheological behavior of PP. The differential scanning calorimetry (DSC) analysis revealed that electron beam irradiation increased the crystallinity percentage and temperature of PP, but decreased the melting temperature. Among all treated samples, the PP20, irradiated at the dose of 20 kGy, showed the highest impact resistance. It had higher Young’s modulus and tensile strength, but lower elongation-at-break in comparison with untreated PP

Purification and Characterization of Carrageenan Extracted from Persian Gulf Laurencia snyderiae Red Algae

Abstract   Background and Objective: Carrageenans can be found in a group of red algae called Carrageenophytes (Gigartinaceae, Solieriaceae, Hypneaceae and Furcellariaceae); howe-ver, this substance has not been investigated in Laurencia species. In this study, two native species of Laurencia within the Persian Gulf were investigated to extract carrageenans. Therefore, the major aims of this study included extraction, optimization and purification of carrageenans from Laurencia snyderiae, a native red algae of Persian Gulf. Material and Methods: Laurencia snyderiae and Laurencia papillosa were identified based on their morphological characteristics. An experimental design was carried out using Design Expert Software to produce and optimize extraction of semi-refined carrageenans. The software programmed 18 treatments based on temperature, boiling time and KOH concentration. Products of the treatments were prepared for rheometric analyses (viscosity measurements). Optimization was carried out using the software based on the maximum viscosity. Refined carrageenan efficiency was assessed using four extraction methods. Moreover, Fourier-transform infrared spectroscopy and nuclear magnetic resonance spectroscopy spectra were compared. Laurencia snyderiae was selected for further inves-tigation. Results and Conclusion: Based on the rheometric analyses, a semi-refined carrageenan solution was identified as a non-Newtonian pseudo-plastic fluid. The optimum treatment was investigated for Laurencia snyderiae at 65 °C for 35 min at KOH concentration of 7% w/v. Results of these two analyses showed that the refined carrageenans from Laurencia snyderiae included the lambda type. The highest efficiency was achieved using dialysis method (37%). Based on the abundance of the Laurencia snyderiae on the Persian Gulf coasts in all seasons, further studies on carrageenan with higher purities enable use of these substance in various industries. Broader rheological studies can precisely assess characteristics of the investigated carrageenans. Conflict of interest: The authors declare no conflict of interest

Repeat-induced epigenetic changes in intron 1 of the frataxin gene and its consequences in Friedreich ataxia

Friedreich ataxia (FRDA), the most common hereditary ataxia, is caused by mutations in the frataxin (FXN) gene. The vast majority of FRDA mutations involve expansion of a GAA•TTC-repeat tract in intron 1, which leads to an FXN mRNA deficit. Bisulfite mapping demonstrates that the region adjacent to the repeat was methylated in both unaffected and affected individuals. However, methylation was more extensive in patients. Additionally, three residues were almost completely methylation-free in unaffected individuals but almost always methylated in those with FRDA. One of these residues is located within an E-box whose deletion caused a significant drop in promoter activity in reporter assays. Elevated levels of histone H3 dimethylated on lysine 9 were seen in FRDA cells consistent with a more repressive chromatin organization. Such chromatin is known to reduce transcription elongation. This may be one way in which the expanded repeats contribute to the frataxin deficit in FRDA. Our data also suggest that repeat-mediated chromatin changes may also affect transcription initiation by blocking binding of factors that increase frataxin promoter activity. Our results also raise the possibility that the repeat-mediated increases in DNA methylation in the FXN gene in FRDA patients are secondary to the chromatin changes