Rotavirus infections and climate variability in Dhaka, Bangladesh: a time-series analysis.

Attempts to explain the clear seasonality of rotavirus infections have been made by relating disease incidence to climate factors; however, few studies have disentangled the effects of weather from other factors that might cause seasonality. We investigated the relationships between hospital visits for rotavirus diarrhoea and temperature, humidity and river level, in Dhaka, Bangladesh, using time-series analysis adjusting for other confounding seasonal factors. There was strong evidence for an increase in rotavirus diarrhoea at high temperatures, by 40.2% for each 1 degrees C increase above a threshold (29 degrees C). Relative humidity had a linear inverse relationship with the number of cases of rotavirus diarrhoea. River level, above a threshold (4.8 m), was associated with an increase in cases of rotavirus diarrhoea, by 5.5% per 10-cm river-level rise. Our findings provide evidence that factors associated with high temperature, low humidity and high river-level increase the incidence of rotavirus diarrhoea in Dhaka

Evaluation of the hydrogen solubility and diffusivity in proton-conducting oxides by converting the PSL values of a tritium imaging plate

Proton-conducting oxides have potential applications in hydrogen sensors, hydrogen pumps, and other electrochemical devices including the tritium purification and recovery systems of nuclear fusion reactors. Although the distribution of hydrogen (H) in such oxide materials is an important aspect, its precise measurement is difficult. In the present study, the hydrogen solubility and diffusivity behavior of BaZr0.9Y0.1O2.95 (BZY), BaZr0.955Y0.03Co0.015O2.97 (BZYC), and CaZr0.9In0.1O2.95 (CZI) were studied using tritiated heavy water vapor i.e., DTO (~2 kPa, tritium (T) = 0.1%) by converting the photostimulated luminescence (PSL) values of the imaging plate (IP). The samples were exposed to DTO vapor at 673 K for 2 h or at 873 K for 1 h. The disc-shaped oxide specimens (diameter ~7.5 mm; thickness ~2.3 mm; theoretical density (TD) > 98 %) were prepared by conventional powder metallurgy. The IP images of the specimen surfaces of all the three materials T-exposed revealed that BZY showed the most uniform T distribution with the highest tritium activity. The cross-sectional T concentration profiles of the cut specimens showed that T diffused deeper into BZY and BZYC than into CZI. The hydrogen solubility and diffusivity in the CZI specimen were lower than that in the BZY and BZYC specimens. This suggested that barium zirconates were more favorable proton conductors than calcium zirconates.Comment: 19 pages, 12 figure

Critical enhancement of thermopower in a chemically tuned polar semimetal MoTe2_{\bf 2}

Ferroelectrics with spontaneous electric polarization play an essential role in today's device engineering, such as capacitors and memories. Their physical properties are further enriched by suppressing the long-range polar order, as is exemplified by quantum paraelectrics with giant piezoelectric and dielectric responses at low temperatures. Likewise in metals, a polar lattice distortion has been theoretically predicted to give rise to various unusual physical properties. So far, however, a "ferroelectric"-like transition in metals has seldom been controlled and hence its possible impacts on transport phenomena remain unexplored. Here we report the discovery of anomalous enhancement of thermopower near the critical region between the polar and nonpolar metallic phases in 1T'-Mo$_{1-x}$Nb$_{x}$Te$_2$ with a chemically tunable polar transition. It is unveiled from the first-principles calculations and magnetotransport measurements that charge transport with strongly energy-dependent scattering rate critically evolves towards the boundary to the nonpolar phase, resulting in large cryogenic thermopower. Such a significant influence of the structural instability on transport phenomena might arise from the fluctuating or heterogeneous polar metallic states, which would pave a novel route to improving thermoelectric efficiency.Comment: 26 pages, 4 figure

Dynamic Centrifuge Tests on Sea Revetment with Multi-Anchors

In the construction of sea revetment, composite type of revetment has been frequently used in Japan, in which huge sized concrete caissons are placed on gravel mound to sustain earth pressure induced by sea reclamation. There are several case records of serious disaster with large displacement of the caisson in huge earthquake. This requires research efforts to find a new type of sea revetment having better static and dynamic performances. A sort of tieback caisson is an idea for the requirement, in which a concrete caisson with relatively small width is reinforced by many anchors. Authors started to study the applicability of this new type of caisson to sea revetment construction, in which a series of centrifuge test has been conducted to investigate its static and dynamic behaviors. In the dynamic tests, the model ground was subjected to several earthquake motions at a 50 g centrifugal acceleration field until the ground failed. The model tests were conducted changing the caisson width and the number and length of anchors. Simple calculations incorporating with the anchor force were also conducted to evaluate stability of the caisson. This paper describes the model ground preparation, test results and calculated results in detail

Oxygen and carbon isotope imaging of organics from Y793495 (CR2) and Murchison (CM2).

第2回極域科学シンポジウム/第34回南極隕石シンポジウム 11月17日（木） 国立国語研究所 2階講