Patterns of racial differences in healthy days measures among adults age 60 and over in Pennsylvania

PUBLIC HEALTH SIGNIFICANCE. Older African Americans are more likely to report poorer self-rated health (SRH) than Caucasians even when individual-level characteristics, such as number of chronic conditions or education, are controlled. One explanation is health pessimism, which posits that African Americans are more pessimistic about their health because of non-health factors, such as perceived discrimination. We examined whether health pessimism or other factors explain the SRH differential between African Americans and Caucasians. METHOD. Research participants were members of the Community Research Registry of the Claude D. Pepper Center at the University of Pittsburgh. The cohort, recruited between 2005 and 2013 (n=2,483), is a convenience sample of residents aged 60+ living in western Pennsylvania. Participants completed the CDC Healthy Days module, which includes questions on SRH. We estimated hierarchical logistic regression models to examine demographic characteristics (race, age, gender, income, and education level), health characteristics (number of diseases), life style characteristics (current tobacco use, alcohol consumption, and physical activity), and perceived number of physically and mentally unhealthy days on reports of poor or fair health. RESULTS. African Americans were 1.6 times (95% CI=1.04, 2.45) more likely to report fair or poor SRH after controlling for demographic and health characteristics. Including lifestyle characteristics, especially physical activity and alcohol consumption attenuated the association, so that African Americans no longer differed from Caucasians in fair-poor SRH. Significant correlates of poorer SRH included male gender, less education, a greater number of diseases, number of reported unhealthy days, less physical activity, and no alcohol consumption. CONCLUSIONS. Health pessimism but also actual poorer health and greater number of behavioral risk factors may be responsible for greater likelihood of fair or poor SRH in older African Americans. Racial differences may partially be addressed through public health effects to improve prevention of disease and reduction of poor life style behaviors

INVESTIGATION OF TUNNELING IN SUPERCONDUCTORS USING A MILLIKELVIN SCANNING TUNNELING MICROSCOPE

In this thesis, I discuss my use of a millikelvin scanning tunneling microscope (STM) to investigate tunneling phenomena in superconductors. As part of an effort to construct an STM to measure the superconducting phase difference, I first describe how I modified a dual-tip scanning tunneling microscope by electrically connecting the two tips together with a short (3 mm) strip of flexible 25 µm thick Nb foil. I also discuss the technique I developed for keeping each tip in feedback when only the total tunnel current through both tips can be measured. I then describe simultaneous room-temperature imaging with both tips on samples of Au/mica and highly oriented pyrolytic graphite (HOPG). Next, I report single-tip results from scanning tunneling microscopy of 25 nm and 50 nm thick films of superconducting TiN at 0.5 K. I found large variations in the tip-sample conductance-voltage characteristics in these samples. At some locations the characteristics showed a clear superconducting gap, as expected for superconductor-normal (S-I-N) tunneling through a high barrier height. At other locations there was a distinct zero-voltage conductance peak, as expected for S-N Andreev tunneling through a low barrier height. I compare the data to the BlonderTinkham-Klapwijk (BTK) theory and the Dynes model of tunneling into a superconductor with broadened density of states. I find that the BTK model provides better fits and reveals a remarkable correlation between the superconducting gap ∆, the temperature T and the barrier height Z. Possible causes for this correlation, including local heating and surface contamination, are discussed. Finally, I describe measurements of I(V) characteristics of a Josephson junction formed by a scanning tunneling microscope with a Nb sample and a Nb tip at 50 mK and 1.5 K. To better understand the physics of this system, I generalized the multiple Andreev reflection (MAR) theory of Averin and Bardas to describe junctions having electrodes with different superconducting gaps. For tunneling resistance Rn between 10 MΩ and 100 kΩ, there was no observable supercurrent at 50 mK or 1.5 K. For Rn between 100 kΩ and about 10 kΩ, the junctions showed hysteretic behavior, with the forward-sweep switching current Is larger than the reverse-sweep retrapping current Ir. In this regime, the critical current I0 was suppressed and the current-voltage characteristics showed a relatively small non-zero resistance R0 at V = 0 that scaled with . For Rn less than the quantum resistance (∼ 12 kΩ), the I-V characteristics deviate from single channel MAR theory. In this limit, the tip makes contact with the sample, as revealed by the dependence of the junction conductance curves on the tip-sample separation. By fitting my two-gap MAR theory to the I(V) data, I obtain superconducting gaps of the tip and sample as a function of the tunnel resistance Rn. I find the sample has nearly the full gap of bulk Nb (∆∼ 1.5 meV), but the tip gap is only about 0.67 meV, and decreases for Rn ≤ 10 kΩ

Producing Daily and Embedded Hourly Rainfall Data Using a Novel Weather Generator

The number of worldwide extreme drought and flood events has risen significantly in recent years. Many studies confer that climate change may cause more intensive and extreme events. Simulating the impact of climate change often requires weather data as inputs to assessment models. Stochastic weather generators have been developed to produce weather data with the same temporal resolution based on the outputs of GCMs. Reservoir simulation normally uses operational rules in daily and hourly time steps for water supply and flood reduction, respectively. Simulating consecutive drought and flood events simultaneously requires a weather generator to produce different temporal resolution data. This work develops a continuous weather generator to generate daily and hourly precipitation data for regular wet days and severe storms, respectively. Daily rainfall data is generated for regular wet days using Exponential distribution or Weibull distribution, while the total rainfall data for severe storms is generated using the Pearson type III or Log Pearson type III distribution. Moreover, hourly rainfall is determined based on generated hyetographs. Simulation results indicate that the proposed continuous weather generator can generate daily and hourly rainfall reasonably. The proposed weather generator is thus highly promising for use in evaluating how climate change impacts reservoir operations that are significantly influenced by more frequent and intensive consecutive drought and flood events

A Comparison of Feature-Combination for Example-Based Super Resolution

[[abstract]]Super resolution (SR) in computer vision is an important task. In this paper, we compared several common used features in image super resolution of example-based algorithms. To combine features, we develop a cascade framework to both solve the problem of deciding weights among features and to improve computation efficiency. Finally, we modify the framework to have an adaptive threshold such that not only the computation load is much reduced but the modified framework is suitable to any query image as well as various image databases.[[sponsorship]]the 18th Pacific-Asia Conference on Knowledge Discovery and Data Mining (PAKDD)[[conferencetype]]國際[[conferencedate]]2014, 5/13 - 5/16[[booktype]]電子版[[iscallforpapers]]Y[[conferencelocation]]Tainan, Taiwa

The Exocyst Component Sec3 Controls Egg Chamber Development Through Notch During Drosophila Oogenesis

The exocyst complex plays multiple roles via tethering secretory or recycling vesicles to the plasma membrane. Previous studies have demonstrated that the exocyst contains eight components, which possibly have some redundant but distinct functions. It is therefore interesting to investigate the biological function of each component. Here, we found that Sec3, one component of exocyst complex, is involved in Drosophila egg chamber development. Loss of sec3 results in egg chamber fusion through the abolishment of cell differentiation. In addition, loss of sec3 increases cell numbers but decreases cell size. These defects phenocopy Notch pathway inactivation. In line with this, loss of sec3 indeed leads to Notch protein accumulation, suggesting that the loss of Sec3 inhibits the delivery of Notch onto the plasma membrane and accumulates inactive Notch in the cytoplasm. Loss of sec3 also leads to the ectopic expression of two Notch pathway target genes, Cut and FasciclinIII, which should normally be downregulated by Notch. Altogether, our study revealed that Sec3 governs egg chamber development through the regulation of Notch, and provides fresh insights into the regulation of oogenesis

Color-tunable mixed photoluminescence emission from Alq3 organic layer in metal-Alq3-metal surface plasmon structure

This work reports the color-tunable mixed photoluminescence (PL) emission from an Alq(3) organic layer in an Au-Alq(3)-Au plasmonic structure through the combination of organic fluorescence emission and another form of emission that is enabled by the surface plasmons in the plasmonic structure. The emission wavelength of the latter depends on the Alq(3) thickness and can be tuned within the Alq(3) fluorescent spectra. Therefore, a two-color broadband, color-tunable mixed PL structure was obtained. Obvious changes in the Commission Internationale d’Eclairage (CIE) coordinates and the corresponding emission colors of Au-Alq(3)-Au samples clearly varied with the Alq(3) thickness (90, 130, and 156 nm)

Reduced expression of alpha-1,2-mannosidase I extends lifespan in Drosophila melanogaster and Caenorhabditis elegans

Exposure to sub-lethal levels of stress, or hormesis, was a means to induce longevity. By screening for mutations that enhance resistance to multiple stresses, we identified multiple alleles of alpha-1,2-mannosidase I (mas1) which, in addition to promoting stress resistance, also extended longevity. Longevity enhancement is also observed when mas1 expression is reduced via RNA interference in both Drosophila melanogaster and Caenorhabditis elegans. The screen also identified Edem1 (Edm1), a gene downstream of mas1, as a modulator of lifespan. As double mutants for both mas1 and Edm1 showed no additional longevity enhancement, it appeared that both mutations function within a common pathway to extend lifespan. Molecular analysis of these mutants revealed that the expression of BiP, a putative biomarker of dietary restriction (DR), is down-regulated in response to reductions in mas1 expression. These findings suggested that mutations in mas1 may extend longevity by modulating DR

Preparation of TiO2 Nanocrystallite Powders Coated with 9 mol% ZnO for Cosmetic Applications in Sunscreens

The preparation of TiO2 nanocrystallite powders coated with and without 9 mol% ZnO has been studied for cosmetic applications in sunscreens by a co-precipitation process using TiCl4 and Zn(NO3)2·6H2O as starting materials. XRD results show that the phases of anatase TiO2 and rutile TiO2 coexist for precursor powders without added ZnO (T-0Z) and calcined at 523 to 973 K for 2 h. When the T-0Z precursor powders are calcined at 1273 K for 2 h, only the rutile TiO2 appears. In addition, when the TiO2 precursor powders contain 9 mol% ZnO (T-9Z) are calcined at 873 to 973 K for 2 h, the crystallized samples are composed of the major phase of rutile TiO2 and the minor phases of anatase TiO2 and Zn2Ti3O8. The analyses of UV/VIS/NIR spectra reveal that the absorption of the T-9Z precursor powders after being calcined has a red-shift effect in the UV range with increasing calcination temperature. Therefore, the TiO2 nanocrystallite powders coated with 9 mol% ZnO can be used as the attenuate agent in the UV-A region for cosmetic applications in sunscreens