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71.
This paper demonstrates the feasibility of using phase stepping and a multicore optical fiber to calculate an object's depth profile. An interference pattern is projected by an optical fiber onto the object. The distorted interference pattern containing the object information is captured by a CCD camera and processed using a phase step interferometry method. The phase step method is less computationally intensive compared to two-dimensional Fourier transform profilometry and provides more accuracy when measuring objects of high frequency spatial variations. 相似文献
72.
Julie Brown Julie Hatfield Wei Du Caroline F. Finch Lynne E. Bilston 《Accident; analysis and prevention》2010,42(6):2144-2148
This cross-sectional study provides population-referenced data on the restraints used and the extent of incorrect restraint use, among child vehicle passengers aged 0–12 years in NSW, Australia. A multistage stratified cluster sampling plan was used to randomly select vehicles from baby/child health clinics, pre-schools/day care centres, and primary schools across NSW to undergo detailed inspection of restraints used by child occupants within those vehicles. Overall, there were very high restraint usage rates (>99% of sampled children) but fewer than one quarter of children were using the correct size-appropriate restraints. Incorrect use (51.4%) was as common as inappropriate use (51.2%). Incorrect use was highest among users of dedicated child restraint systems (OR 16.0, 95% CI 6.9–36.0), and was more likely among those using size-appropriate restraints than those using inappropriate restraints (OR 1.8 95% CI 1.1–3.2); and among convertible restraints than those designed for a single mode of use (OR 1.5 95% CI 1.2–1.7). As incorrect use substantially reduces the protection from injury that is offered by child restraints, it is important that future strategies to reduce casualties among child occupants target both inappropriate and incorrect use. 相似文献
73.
Cox Dena S.; Cox Anthony D.; Sturm Lynne; Zimet Greg 《Canadian Metallurgical Quarterly》2010,29(1):29
Objective: To determine the most effective ways to present human papillomavirus (HPV) vaccine risk and benefit information to mothers in Hispanic, African American, and White communities, to increase mothers’ intentions to vaccinate their daughters against HPV. Design: The study used a 3 × 2 between-subjects factorial design, involving 3 different risk presentation formats (graphical HPV statistics, nongraphical HPV statistics, or no-statistics control) and the presence or absence of rhetorical questions (RQ). Data were collected from a national sample of 471 mothers of girls ages 11–16. Main Outcome Variables: The primary outcome variable was mothers’ intention to vaccinate their daughters against HPV. Secondary outcomes included mothers’ self-reported message comprehension and perceptions of daughters’ vulnerability to HPV infection, infection severity, vaccine efficacy, and obstacles to immunization. Results and Conclusion: Results showed that both risk presentation format and RQs had an overall positive effect on mothers’ intention to vaccinate their daughters. However, the interventions appear to be more effective when used separately than when used in combination. Each of these interventions is brief and could easily be implemented by health care providers as well as in patient health communication literature. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
Bon‐Cheol Ku Dae Kyom Kim Jun Seok Lee Alexandre Blumstein Jayant Kumar Lynne A. Samuelson 《Polymer Composites》2009,30(12):1817-1824
Water‐soluble single‐walled carbon nanotube‐polyacetylene [SWNT‐PA, SWNT‐P(2EPy‐MeTf)] nanocomposites have been synthesized by using the surface initiated “grafting‐from” method. The FT‐IR spectra confirmed the formation of an amide bond between the functionalized SWNTs and the initiator, 4‐(2‐Aminoethyl) pyridine, to polymerize N‐Methyl‐2‐ethynlypyridinium triflate (2EPy‐MeTf). UV‐vis spectroscopy indicated that the degree of polymerization of P(2EPy‐MeTf) in the SWNT‐polyacetylene composites is 15, based on the Lewis‐Calvin equation. The SWNT‐polyacetylene composites have been characterized by TGA, AFM, and TEM. From TGA analysis, the loading of SWNTs in the SWNT grafted ionic polyacetylenes is estimated to be 22%. AFM and TEM images clearly showed that the nanotube is wrapped with the PA. The SWNT‐polyacetylene composites displayed high water solubility (8 mg/ml). The room temperature electrical conductivity of the doped SWNT‐polyacetylene composites was found to be in the range of 10−3 to 10−4 S/cm, an order of magnitude of increase over neat P(2EPy‐MeTf) and a two order of magnitude increase over Dendrimer‐polyacetylen composites. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers 相似文献
75.
Sagnella SM Gong X Moghaddam MJ Conn CE Kimpton K Waddington LJ Krodkiewska I Drummond CJ 《Nanoscale》2011,3(3):919-924
We demonstrate that oral delivery of self-assembled nanostructured nanoparticles consisting of 5-fluorouracil (5-FU) lipid prodrugs results in a highly effective, target-activated, chemotherapeutic agent, and offers significantly enhanced efficacy over a commercially available alternative that does not self-assemble. The lipid prodrug nanoparticles have been found to significantly slow the growth of a highly aggressive mouse 4T1 breast tumour, and essentially halt the growth of a human MDA-MB-231 breast tumour in mouse xenografts. Systemic toxicity is avoided as prodrug activation requires a three-step, enzymatic conversion to 5-FU, with the third step occurring preferentially at the tumour site. Additionally, differences in the lipid prodrug chemical structure and internal nanostructure of the nanoparticle dictate the enzymatic conversion rate and can be used to control sustained release profiles. Thus, we have developed novel oral nanomedicines that combine sustained release properties with target-selective activation. 相似文献
76.
Demographic, health, cognitive, and sensory variables as predictors of mortality in very old adults.
Anstey Kaarin J.; Luszcz Mary A.; Giles Lynne C.; Andrews Gary R. 《Canadian Metallurgical Quarterly》2001,16(1):3
Cognitive and sensorimotor predictors of mortality were examined in the Australian Longitudinal Study of Ageing, controlling for demographic and health variables. A stratified random sample of 1,947 males and females aged 70 and older were interviewed, and 1,500 were assessed on measures of health, memory, verbal ability, processing speed, vision, hearing, and grip strength in 1992 and 1994. Analyses of incident rate ratios for mortality over 4- and 6-year periods were conducted using Cox hierarchical regression analyses. Results showed that poor performance on nearly all cognitive variables was associated with mortality, but many of these effects were explained by measures of self-rated health and disease. Significant decline in hearing and cognitive performance also predicted mortality as did incomplete data at Wave 1. Results suggest that poor cognitive performance and cognitive decline in very old adults reflect both biological aging and disease processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
A simple solution-based approach for depositing CIGS (Cu-In-Ga-Se/S) absorber layers is discussed, with an emphasis on film characterization, interfacial properties and integration into photovoltaic devices. The process involves incorporating all metal and chalcogenide components into a single hydrazine-based solution, spin coating a precursor film, and heat treating in an inert atmosphere, to form the desired CIGS film with up to micron-scaled film thickness and grain size. PV devices (glass/Mo/CIGS/CdS/i-ZnO/ITO) employing the spin-coated CIGS and using processing temperatures below 500 °C have yielded power conversion efficiencies of up to 10% (AM 1.5 illumination), without the need for a post-CIGS-deposition treatment in a gaseous Se source or a cyanide-based bath etch. Short-duration low-temperature (T < 200 °C) oxygen treatment of completed devices is shown to have a positive impact on the performance of initially underperforming cells, thereby enabling better performance in devices prepared at temperatures below 500 °C. 相似文献
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