645 research outputs found
Thermoelectric properties of the layered Pd oxide R_2PdO_4 (R = La, Nd, Sm and Gd)
We prepared polycrystalline samples of RPdO (R = La, Nd, Sm and Gd)
using a NaCl-flux technique. The measured resistivity is of the order of
10 cm at room temperature, which is two orders of magnitude
smaller than the values reported so far. We further studied the substitution
effects of Ce for Nd in NdCePdO, where the substituted Ce
decreases the resistivity and the magnitude of the thermopower. The activation
energy gap of 70-80 meV and the effective mass of 15 evaluated from the
measured data are suitable for thermoelectric materials, but the mobility of
10 cm/Vs is much lower than a typical value of 1-10 cm/Vs for
other thermoelectric oxides.Comment: 5 pages, 5 figures, to appear in J. Phys. Soc. Jp
Effect of base–acid properties of the mixtures of water with methanol on the solution enthalpy of selected cyclic ethers in this mixture at 298.15 K
The enthalpies of solution of cyclic ethers: 1,4-
dioxane, 12-crown-4 and 18-crown-6 in the mixture of
water and methanol have been measured within the whole
mole fraction range at T = 298.15 K. Based on the obtained
data, the effect of base–acid properties of water–
methanol mixtures on the solution enthalpy of cyclic ethers
in these mixtures has been analyzed. The solution enthalpy
of cyclic ethers depends on acid properties of water–
methanol mixtures in the range of high and medium water
contents in the mixture. Based on the analysis performed, it
can be assumed that in the mixtures of high methanol
contents, cyclic ethe
High susceptibility to lipopolysaccharide-induced lethal shock in encephalomyocarditis virus-infected mice
Secondary bacterial infection in humans is one of the pathological conditions requiring clinical attention. In this study, we examined the effect of lipopolysaccharide (LPS) on encephalomyocarditis virus (EMCV) infected mice. All mice inoculated with EMCV at 5 days before LPS challenge died within 24 h. LPS-induced TNF-α mRNA expression was significantly increased in the brain and heart at 5 days after EMCV infection. CD11b+/TLR4+ cell population in the heart was remarkably elevated at 5 days after EMCV infection, and sorted CD11b+ cells at 5 days after EMCV infection produced a large amount of TNF-α on LPS stimulation in vivo and in vitro. In conclusion, we found that the infiltration of CD11b+ cells into infected organs is involved in the subsequent LPS-induced lethal shock in viral encephalomyocarditis. This new experimental model can help define the mechanism by which secondary bacterial infection causes a lethal shock in viral encephalomyocarditis
Hypertensive patients' perceptions of their physicians' knowledge about them: a cross-sectional study in Japan
<p>Abstract</p> <p>Background</p> <p>In order to evaluate the difference in quality of primary care provided by physicians between the types of medical institutions in Japan, we examined whether the physicians' comprehensive knowledge of their patients is perceived differently by the patients seen at clinics and hospitals.</p> <p>Methods</p> <p>Patients with prescriptions for hypertensive drugs were approached sequentially at 13 pharmacies, and were administered a questionnaire on their perception of their physician's knowledge about them. Data were obtained for 687 patients (362 from clinics and 325 from hospitals). A physician's knowledge of his or her patients was assessed according to six aspects: their medical history, their current medications, history of allergy, what worries patients most about their health, patients' values and beliefs on their health, and patients' roles and responsibilities at work, home, or school. Responses were scored from 1 through 6 (1: knows very well; 6: doesn't know at all).</p> <p>Results</p> <p>Patients treated in clinics were seen more frequently, for a longer period, and had fewer complications than the patients who were treated in hospitals. Among the six aspects of physicians' knowledge assessed, 79.3% of the patients reported that their physicians knew their complete list of medications "very well or well," while 28.3% reported the same about their roles and responsibilities at work, home, or school. Physicians in clinics were considered to know their patients' worries about their health (p = 0.004) and the roles and responsibilities of the patients at work, home, or school (p = 0.028) well. Multiple regression analysis showed that the type of medical institutions remained as a significant variable only for the aspect of patients' worries about their health. The factor that consistently affected the patients' perception of physicians' knowledge about them was the patients' age.</p> <p>Conclusions</p> <p>Hypertensive patients' perceptions of their physicians' knowledge about them did not differ significantly between clinics and hospitals in Japan for most of the aspects. In order to differentiate the roles of physicians in hospitals and clinics better and ensure the quality of primary care, the establishment of a standardized educational system to train primary care physicians better is recommended.</p
Animated molecular dynamics simulations of hydrated caesium-smectite interlayers
Computer animation of center of mass coordinates obtained from 800 ps molecular dynamics simulations of Cs-smectite hydrates (1/3 and 2/3 water monolayers) provided information concerning the structure and dynamics of the interlayer region that could not be obtained through traditional simulation analysis methods. Cs(+ )formed inner sphere complexes with the mineral surface, and could be seen to jump from one attracting location near a layer charge site to the next, while water molecules were observed to migrate from the hydration shell of one ion to that of another. Neighboring ions maintained a partial hydration shell by sharing water molecules, such that a single water molecule hydrated two ions simultaneously for hundreds of picoseconds. Cs-montmorillonite hydrates featured the largest extent of this sharing interaction, because interlayer ions were able to inhabit positions near surface cavities as well as at their edges, close to oxygen triads. The greater positional freedom of Cs(+ )within the montmorillonite interlayer, a result of structural hydroxyl orientation and low tetrahedral charge, promoted the optimization of distances between cations and water molecules required for water sharing. Preference of Cs(+ )for locations near oxygen triads was observed within interlayer beidellite and hectorite. Water molecules also could be seen to interact directly with the mineral surface, entering its surface cavities to approach attracting charge sites and structural hydroxyls. With increasing water content, water molecules exhibited increased frequency and duration of both cavity habitation and water sharing interactions. Competition between Cs(+ )and water molecules for surface sites was evident. These important cooperative and competitive features of interlayer molecular behavior were uniquely revealed by animation of an otherwise highly complex simulation output
Gamma-Ray Spectroscopy in Lambda Hypernuclei
The present status of hypernuclear gamma-ray spectroscopy with Hyperball is
summarized. We observed two gamma transitions of 16-Lambda-O(1- -> 1-,0-) and
obtained the strength of the Lambda-N tensor force. In 10B(K-,pi- gamma) data,
we did not observe the spin-flip M1 transition of 10-Lambda-B(2- -> 1-), but
gamma rays from hyperfragments such as 7-Lambda-Li(7/2+ -> 5/2+) and
9-Lambda-Be(3/2+ ->1/2+) were observed. In 11B(pi+,K+ gamma) data, we observed
six gamma transitions of 11_Lambda-B. We also attempted an inclusive gamma-ray
measurement with stopped K- beam.Comment: 10 pages, 9 figures, 8th International Conference on Hypernuclear and
Strange Particle Physics (HYP2003), Newport News, Virginia, 14-18 Oct 2003,
to appear in Nuclear Physics
- …