1,069 research outputs found

    Heat Capacity study of β\beta-FeSi2_2 single crystals

    Full text link
    Heat Capacity of needle-like [length=5mm, diameter=1 mm] β\beta-FeSi2_{2} single crystal, grown by chemical vapor transport has been measured. Two anomalies are found, a broad deviation centered around 160 K and a clear deviation at a temperature of 255 K approximately. We have attempted to relate these to the anomalies previously reported in the case of the resistivity data. The Transient Thermoelectric Effect [TTE] results lead us to the inference that the system under goes from single carrier system to at least two carrier system at 220 K-our heat capacity results seem to provide further independent evidence for this transition in this system.Comment: 8 pages, 5 figure

    A non-resonant RF cavity loaded with amorphous alloy for proton cancer therapy

    Get PDF
    A non-resonant RF cavity loaded with amorphous alloy cores has been designed and tested. The cavity has a re-entrant structure loaded with 8 amorphous alloy toroidal core and its characteristic impedance is designed as 450 Omega . The RF power is fed by 1 kW solid state amplifier using a step-up transformer with 1:9 impedance ratio. In the high power test, an accelerating gap voltage of more than 900 V was measured with input power of 1 kW in the frequency range of 1 to 10 MHz. The voltage standing wave ratio (VSWR) was less than 2.0. The results prove that the cavity may be used successfully within a compact proton synchrotron for a cancer therapy facility. (3 refs)

    Healthy aging: comparative analysis of local perception and diet in two health districts of Côte d'Ivoire and Japan

    Get PDF
    Context: Good health and longevity depend on dynamic interactions between biological, social, psychological, and environmental factors. Aging is globally a big challenge, particularly with the demographic transition, including population growth, and an emerging burden to society. Knowledge, behavior, diet, and consumption of animal source food were related to aging and emerged as the key factors modulating healthy aging. Objective: The study was designed to understand the main healthy aging factors, such as knowledge, social network, and diet of elders, and to derive mutual learning from it for healthy aging. Methods: A qualitative approach has been applied to explore health-related knowledge, attitude, and diet of elders from Ebetsu (Japan) and Tiassale (Cote d'Ivoire) health districts, using focus group discussions and comparative context analysis between high- and low-income countries. Results: The study shows that living longer is a common feature of people in Japan compared to Cote d'Ivoire, where the life expectancy is still low. Both groups of elders have social networks that support them, and both offer their gained experience to society. While Japanese elders depend on pension and insurance for income and medical treatments, Ivorians depend mostly on their children and social network in old age. The worries of elders differ between the two regions. In Ebetsu, elder members of the community are concerned about the future burden they pose for the younger generation if they develop ill-health, making them more resilient to aging. In Taabo, elders are considered to be culturally and socially useful to the society. Elders in Ebetsu pointed out that for healthy aging, education on diet at a younger age, physical activities, and access to basic social services are the key aspects. This was not observed in Taabo's context. Being inactive and dependent on others were described as the most worrying situations for elders in Ebetsu, as it is perceived to increase the risk of non-communicable diseases and anxiety. Elders in Ebetsu have good knowledge on what constitutes a healthy diet, and they believe that diversifying their diet, reducing portions, and substituting red meat with good animal and vegetable proteins are best eating practices to maintain good health. In Cote d'Ivoire, the diet is imbalanced and the whole family consumes the same meal made mainly with high-energy staples and little protein. However, it is observed in both societies that adopting a good diet is very expensive. Conclusion: The consciousness of aging is universal, but healthy aging varies according to the social systems, education, and knowledge on diet transition. Physical activities, protein-energy balance in diet, and social networks are the key for healthy aging in both contexts. The challenge is to find ways to increase knowledge regarding healthy aging and to strengthen the support system so that healthy aging becomes affordable

    Water Splitting Photovoltaic-Photoelectrochemical GaAs/InGaAsP - WO3/BiVO4 Tandem Cell with Extremely Thin Absorber Photoanode Structure

    Get PDF
    We demonstrate highly efficient solar hydrogen generation via water splitting by photovoltaicphotoelectrochemical (PV-PEC) tandem device based on GaAs/InGaAsP (PV cell) and WO3/BiVO4 core/shell nanorods (PEC cell). We utilized extremely thin absorber (ETA) concept to design the WO3/BiVO4 core/shell heterojunction nanorods and obtained the highest efficiencies of photo-induced charge carriers generation, separation and transfer that are possible for the WO3/BiVO4 material combination. The PV-PEC tandem shows stable water splitting photocurrent of 6.56 mA cm-2 under standard AM1.5G solar light that corresponds to the record solar-to-hydrogen (STH) conversion efficiency of 8.1%

    Prediction of Transcriptional Terminators in Bacillus subtilis and Related Species

    Get PDF
    In prokaryotes, genes belonging to the same operon are transcribed in a single mRNA molecule. Transcription starts as the RNA polymerase binds to the promoter and continues until it reaches a transcriptional terminator. Some terminators rely on the presence of the Rho protein, whereas others function independently of Rho. Such Rho-independent terminators consist of an inverted repeat followed by a stretch of thymine residues, allowing us to predict their presence directly from the DNA sequence. Unlike in Escherichia coli, the Rho protein is dispensable in Bacillus subtilis, suggesting a limited role for Rho-dependent termination in this organism and possibly in other Firmicutes. We analyzed 463 experimentally known terminating sequences in B. subtilis and found a decision rule to distinguish Rho-independent transcriptional terminators from non-terminating sequences. The decision rule allowed us to find the boundaries of operons in B. subtilis with a sensitivity and specificity of about 94%. Using the same decision rule, we found an average sensitivity of 94% for 57 bacteria belonging to the Firmicutes phylum, and a considerably lower sensitivity for other bacteria. Our analysis shows that Rho-independent termination is dominant for Firmicutes in general, and that the properties of the transcriptional terminators are conserved. Terminator prediction can be used to reliably predict the operon structure in these organisms, even in the absence of experimentally known operons. Genome-wide predictions of Rho-independent terminators for the 57 Firmicutes are available in the Supporting Information section
    corecore