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91.
R.G. Poulos J. Hatfield C. Rissel L.K. Flack S. Murphy R. Grzebieta A.S. McIntosh 《Accident; analysis and prevention》2015
This paper examines self-reported prospectively collected data from 2038 adult transport and recreational cyclists from New South Wales (Australia) to determine exposure-based incident crash and injury rates. During 25,971 days of cycling, 198 crashes were reported, comprising approximately equal numbers of falls and collisions. The overall crash rate was 0.290 (95% CI, 0.264–0.319) per 1000 km or 6.06 (95% CI, 5.52–6.65) per 1000 h of travel. The rate of crashes causing any injury (self-treated, or medically attended without overnight hospital stay) was 0.148 (95% CI, 0.133–0.164) per 1000 km or 3.09 (95% CI, 2.79-3.43) per 1000 h of travel. The rate of crashes causing a medically attended injury (without overnight hospital stay) was 0.023 (95% CI, 0.020–0.027) per 1000 km or 0.49 (95% CI, 0.43-0.56) per 1000 h of travel. No injuries requiring an overnight stay in hospital were reported on days meeting the inclusion criteria. After adjustment for exposure in hours, or for the risks associated with different infrastructure utilisation, the rates of crashes and medically attended injuries were found to be greater for females than males, less experienced than more experienced cyclists, and for those who rode mainly for transport rather than mainly for recreation. Comparison of estimated crash and injury rates on different infrastructure types were limited by the small number of events, however findings suggest that the separation of cyclists from motorised traffic is by itself not sufficient to ensure safe cycling. 相似文献
92.
93.
S. Iyer J. McIntosh A. Bandyopadhyay N. Langrana A. Safari S. C. Danforth R. B. Clancy C. Gasdaska P. J. Whalen 《International Journal of Applied Ceramic Technology》2008,5(2):127-137
We present processing (green and sintered), part shrinkage and warping, microstructural characterization, and mechanical properties of Si3 N4 made by fused deposition of ceramics (FDC), using optical microscopy, scanning electron microscopy, and X-ray diffraction. The mechanical properties (fracture strength, fracture toughness, and Weibull modulus) are also reported. Proper FDC build parameters resulted in dense, homogeneous, near-net-shape Si3 N4 , with microstructures and mechanical properties similar to conventionally processed material. Mechanical properties are shown to be isotropic, while there is some degree of microstructural texturing (preferred β-Si3 N4 grain orientation) in sintered components. 相似文献
94.
95.
The application of a luminescent down-shifting (LDS) layer has been proposed as a method for improving the poor spectral response (SR) of solar cells to short-wavelength light. The LDS layer absorbs photons, typically in the 300-500 nm range, and re-emits them at a longer wavelength where the photovoltaic (PV) device exhibits a significantly better response. This paper reviews the progress in this area over the last three decades, starting from early experiments that yielded promising results but being limited by the luminescent materials available at the time, to modern materials that exhibit higher luminescent quantum efficiencies and better photostability. The candidate materials are considered and their potential is reviewed for a wide range of PV technologies. A particular opportunity is the ability to use the existing polymer encapsulation layer of certain PV technologies as a LDS layer as well. 相似文献
96.
97.
Barbara P. Atshaves Avery L. McIntosh Stephen M. Storey Kerstin K. Landrock Ann B. Kier Friedhelm Schroeder 《Lipids》2010,45(2):97-110
Since liver fatty acid binding protein (L-FABP) facilitates uptake/oxidation of long-chain fatty acids in cultured transfected
cells and primary hepatocytes, loss of L-FABP was expected to exacerbate weight gain and/or obesity in response to high dietary
fat. Male and female wild-type (WT) and L-FABP gene-ablated mice, pair-fed a defined isocaloric control or high fat diet for
12 weeks, consumed equal amounts of food by weight and kcal. Male WT mice gained weight faster than their female WT counterparts
regardless of diet. L-FABP gene ablation enhanced weight gain more in female than male mice—an effect exacerbated by high
fat diet. Dual emission X-ray absorptiometry revealed high-fat fed male and female WT mice gained mostly fat tissue mass (FTM).
L-FABP gene ablation increased FTM in female, but not male, mice—an effect also exacerbated by high fat diet. Concomitantly,
L-FABP gene ablation decreased serum β-hydroxybutyrate in male and female mice fed the control diet and, even more so, on
the high-fat diet. Thus, L-FABP gene ablation decreased fat oxidation and sensitized all mice to weight gain as whole body
FTM and LTM—with the most gain observed in FTM of control vs high-fat fed female L-FABP null mice. Taken together, these results
indicate loss of L-FABP exacerbates weight gain and/or obesity in response to high dietary fat. 相似文献
98.
TJ Marten 《Canadian Metallurgical Quarterly》1999,103(1):224-236
Many patients seeking rejuvenation of their foreheads have high hairlines and are troubled by the prospect that surgery will worsen the deformity. Hairline elevation occurs in both coronal and endoscopic foreheadplasty techniques and is at least part of the reason that many surgeons do not always recommend these procedures when otherwise indicated. Although a pretrichial "hairline" incision prevents hairline retro-displacement, it results in forehead shortening only and not true hairline lowering. When a pretrichial incision is used in combination with a posterior scalp advancement flap, however, true hairline lowering is possible. Experience with this technique encompasses 27 procedures performed over a 5-year period. Patients ranged in age from 35 to 71 years. A significant improvement was demonstrable in all cases and corresponded with a high degree of patient satisfaction. No serious complications were seen. A high hairline must be recognized as the source of both a disproportionate and aged appearance. The ability to lower the hairline and place it in a more proportionate, youthful relationship with the rest of the face adds a new dimension to foreheadplasty equal to or greater in importance to an overall improved appearance as other maneuvers typically performed during the procedure. For many patients, the benefits of hairline lowering far outweigh the trade-off of a more anteriorly situated, and possibly more visible, scar. 相似文献
99.
100.
Protein kinase C (PKC) acutely increases calcium currents in Aplysia bag cell neurons by recruiting calcium channels different from those constitutively active in the plasma membrane. To study the mechanism of PKC regulation we previously identified two calcium channel alpha1-subunits expressed in bag cell neurons. One of these, BC-alpha1A, is localized to vesicles concentrated primarily in somata and growth cones. We used antibodies to BC-alpha1A to analyze its expression in the bag cell neurons of juvenile Aplysia at a developmental stage at which PKC-sensitive calcium currents have previously been shown to be low. We find that vesicular BC-alpha1A staining is generally reduced in juvenile bag cell neurons but that its expression level can vary among juvenile animals. In 17 bag cell clusters examined, the percentage of neurons that displayed punctate alphaBC-alpha1A staining ranged from 0 to 85%. Sampling of calcium currents from cells of the same clusters by whole cell patch-clamp techniques revealed that the PKC-sensitive calcium current density is significantly correlated with the degree of vesicular staining. In contrast, no correlation of basal calcium current levels with aBC-alpha1A staining was found. These results strongly suggest that BC-alpha1A, a member of the ABE-subfamily of calcium channels, carries the PKC-sensitive calcium current in bag cell neurons. They are consistent with a model in which PKC recruits channels from the vesicular pool to the plasma membrane. 相似文献