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21.
The authors present their experiences in assisting the government of Niger to develop automated information systems for health care management. They discuss the structure of the health system, the role of donor assistance, the process of initiating automated systems, and the technical requirements and costs of the system. Finally, they draw general conclusions that may be useful for those attempting similar efforts. 相似文献
22.
Z Kato N Shimozawa J Kokuzawa M Iwamura T Hirata A Yamagishi T Hayashi T Motoyoshi N Kondo 《Canadian Metallurgical Quarterly》1998,40(2):138-142
INTRODUCTION: Intervention studies to reduce cigarette sales to minors have been conducted primarily in suburban settings. Little is known about sociocultural factors influencing cigarette sales to minors in urban settings. This study sought to determine sociodemographic and cultural factors that may play a role in cigarette sales and in efforts to reduce sales to minors in urban areas. METHODS: Merchant education and follow-up surveys were conducted in small local stores in predominantly African-American urban census tracts in Baltimore. The stores had prior evidence of cigarette sales to minors. RESULTS: Merchants reported hostility (66%) and foul language (64%) when they requested youth identification. Youthful-oriented advertising of cigarettes was highly prevalent in all stores and moreso in stores owned and staffed by Asian merchants. Advertising with specific youthful content was predictive (OR = 3.97; 95% CI = 1.70, 9.23; P = .0014) of higher requests for cigarettes from minors. CONCLUSIONS: Youth-oriented cigarette advertising is a prevalent environmental risk for urban youth. Differences between Asian and African-American merchants suggest socioethnic factors may be an influential component of illegal sales and educational campaigns to reduce smoking among minors. 相似文献
23.
Yukari Totsuka Takashi Higuchi Toshio Imai Akiyoshi Nishikawa Takehiko Nohmi Tatsuya Kato Shuich Masuda Naohide Kinae Kyoko Hiyoshi Sayaka Ogo Masanobu Kawanishi Takashi Yagi Takamichi Ichinose Nobutaka Fukumori Masatoshi Watanabe Takashi Sugimura Keiji Wakabayashi 《Particle and fibre toxicology》2009,6(1):1-11
Background
Recently, manufactured nano/microparticles such as fullerenes (C60), carbon black (CB) and ceramic fiber are being widely used because of their desirable properties in industrial, medical and cosmetic fields. However, there are few data on these particles in mammalian mutagenesis and carcinogenesis. To examine genotoxic effects by C60, CB and kaolin, an in vitro micronuclei (MN) test was conducted with human lung cancer cell line, A549 cells. In addition, DNA damage and mutations were analyzed by in vivo assay systems using male C57BL/6J or gpt delta transgenic mice which were intratracheally instilled with single or multiple doses of 0.2 mg per animal of particles.Results
In in vitro genotoxic analysis, increased MN frequencies were observed in A549 cells treated with C60, CB and kaolin in a dose-dependent manner. These three nano/microparticles also induced DNA damage in the lungs of C57BL/6J mice measured by comet assay. Moreover, single or multiple instillations of C60 and kaolin, increased either or both of gpt and Spi- mutant frequencies in the lungs of gpt delta transgenic mice. Mutation spectra analysis showed transversions were predominant, and more than 60% of the base substitutions occurred at G:C base pairs in the gpt genes. The G:C to C:G transversion was commonly increased by these particle instillations.Conclusion
Manufactured nano/microparticles, CB, C60 and kaolin, were shown to be genotoxic in in vitro and in vivo assay systems. 相似文献24.
Macroporous organic–inorganic polymer hybrids were prepared from poly(vinyl pyrrolidone), and inorganic alkoxides. To a reaction mixture of poly(vinyl pyrrolidone) and tetramethoxysilane, extract from tea leafs and HCl aqueous solution in methanol were added. The resulting mixture was constantly stirred at room temperature for 1 h and heated at 60°C for two weeks. Consequently, the corresponding polymer hybrid became a macroporous material having a pore size from 3.26 to 20.86 μm. We succeeded in finding that the pruned tea leafs were able to utilize the synthesis of novel macroporous materials. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
25.
Sudu Siqing Hui Wu Hiroki Yamaguchi Takamichi Shinohara Osami Sakata Atsushi Takahara 《Polymer Bulletin》2013,70(1):105-115
Nanoimprint lithography (NIL) was carried out on precursor of polyimide (PI), poly(amic acid) film, and then hard baking to obtain imprinted PI film. The molecular aggregation states of imprinted PI films before and after hard baking were investigated by grazing-incidence wide-angle X-ray diffraction comparing with the one of flat PI film. It was found that NIL and hard baking can strongly affect the molecular aggregation states of PI film. Before hard baking, PI chain is aligned parallel to the line direction on the line. After hard baking, the alignment in ordered domain was changed to that the PI molecule of which chain axis is perpendicular to the line direction is significantly increased, while, PI molecule of which chain axis is parallel to the line direction is decreased after hard baking. Through comparing with the flat PI, crystallinity of imprinted PI film has been significantly enhanced. 相似文献
26.
Hidenori Okuzaki Kosuke Hosaka Hiroki Suzuki Takamichi Ito 《Reactive and Functional Polymers》2013,73(7):986-992
Free-standing films made of poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate) (PEDOT/PSS) with various PSS contents were newly prepared by casting water dispersion of the PEDOT/PSS colloidal particles in the presence of an extra PSS. Electrical conductivity, morphology, water vapor sorption, and electro-active polymer actuating behavior of the resulting films were investigated by means of four-point method, atomic force microscope (AFM), sorption isotherm, and electromechanical analyses. The maximum contraction of the film by application of an electric field increased with increasing both PSS content and relative humidity (RH), where the value attained 7% at 70% RH for the film with 93% of PSS. Since the isothermal sorption curve of the film was less dependent on the PSS content, the significant increase of the film contraction was explained by two mechanisms: (i) the extra PSS prevented from hydrogen bonding between adjacent PEDOT/PSS particles that suppressed dimensional changes of the film; and (ii) the higher the RH, the larger the degree of water vapor sorption, which led to the large film contraction by desorption of water vapor via Joule heating. On the basis of this phenomenon linear actuators utilizing PEDOT/PSS films were successfully developed and applied to leverage actuator and Braille cell. 相似文献
27.
Sound velocity values for 32 liquid metals at their melting point temperatures have been predicted using two models that we
presented; most of these metals are transition and rare earth metals. The sound velocities for most of these liquid metals
have yet to be measured experimentally. Dimensionless common parameters, denoted by
x\textT1/2 \xi_{\text{T}}^{1/2} and
x\textE1/2 , \xi_{\text{E}}^{1/2} , were determined on the basis of the predicted sound velocities. These common parameters, which characterize the liquid state
(i.e., an atom’s hardness or softness and its anharmonic motions), allow for better predictions of several thermophysical properties
(e.g., surface tension, viscosity, self-diffusivity, volume expansivity) of liquid metallic elements. The values of both the common
parameters
x\textT1/2 \xi_{\text{T}}^{1/2} and
x\textE1/2 \xi_{\text{E}}^{1/2} vary periodically with atomic number. Using our viscosity model in terms of the parameter
x\textT1/2 , \xi_{\text{T}}^{1/2} , values of melting point viscosity were calculated for liquid molybdenum and platinum. The agreement obtained between calculated
and experimental values is good when using predicted values of
x\textT1/2 \xi_{\text{T}}^{1/2} to calculate their viscosities. 相似文献
28.
Yoshiyuki Kobayashi Takamichi Takashima Mieko Hayashi Hiroshi Fujimoto 《IEEE transactions on neural systems and rehabilitation engineering》2005,13(1):53-59
Tactile ground surface indicators installed on sidewalks help visually impaired people walk safely. The visually impaired distinguish the indicators by stepping into its convexities and following them. However, these indicators sometimes cause the nonvisually impaired to stumble. This study examines the effects of these indicators by comparing the kinematic and kinetic variables of walking on paths with and without indicators. The results suggest that walking on the indicators causes extra movements of the lower extremities such as increased minimum toe heights during the midswing phase, increased peak hip flex moments, and increased peak hip heights. This study also suggests that a functional leg length discrepancy while walking on the indicators is one of the reasons for the extra movements of the lower extremities. Therefore, we designed a new recessed tactile surface to offset the differences of surface depth while walking on the path containing indicators, and found that the newly designed recessed tactile surface was effective in reducing the extra movements while walking on the path in which indicators were installed. These indicators may help both the visually impaired and elderly people with normal vision to walk safely. 相似文献
29.
Takamichi Ogino Yasuo Nishizawa Toshihiko Morioka Norio Naito Mamoru Tani Yushi Fujita 《Reliability Engineering & System Safety》1988,22(1-4)
This paper describes the MITI (Ministry of International Trade and Industry) projects for decision support systems for NPPs in Japan. Main attention is paid to the new project of an advanced man-machine system for nuclear power plants, of which a conceptual design was initiated in 1984. Some of the aspects of the design and the outline of the prototype system are discussed. 相似文献
30.