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991.
Tay R 《Accident; analysis and prevention》2005,37(5):922-929
This study re-evaluated the effectiveness of the anti-drink driving and anti-speeding enforcement and publicity campaigns implemented in the Australian State of Victoria which have thus far yielded mixed results in several evaluations. As opposed to previous evaluations, this study focused on the effects of these campaigns on young male drivers who formed the primary target and examined the combined effects of the campaigns on the total number of serious crashes. Our results showed that the anti-drink driving enforcement and publicity campaigns had a significant independent effect in reducing crashes but their interactive effect was anti-complementary. Conversely, the anti-speeding enforcement and publicity campaigns had no independent effect but their interactive effect was significant in reducing serious crashes involving young male drivers. 相似文献
992.
Wavelet analysis of speckle patterns with a temporal carrier 总被引:5,自引:0,他引:5
A novel temporal phase-analysis technique that is based on wavelet analysis and a temporal carrier is presented. To measure displacement on a vibrating object by using electronic speckle pattern interferometry, one captures a series of speckle patterns, using a high-speed CCD camera. To avoid ambiguity in phase estimation, a temporal carrier is generated by a piezoelectric transducer stage in the reference beam of the interferometer. The intensity variation of each pixel on recorded images is then analyzed along the time axis by a robust mathematical tool, i.e., a complex Morlet wavelet transform. After the temporal carrier is removed, the absolute displacement of a vibrating object is obtained without the need for temporal or spatial phase unwrapping. The results obtained by a wavelet transform are compared with those from a temporal Fourier transform. 相似文献
993.
The three-dimensional pore structures in waste activated sludge floc were identified using the fluorescence in situ hybridization (FISH) and confocal laser scanning microscope (CLSM) images. The meshes of the three-dimensional porous configuration of a sludge floc were constructed from the CLSM series images. The intrafloc flow field was simulated for the constructed floc model when it was subjected to a uniform flow field, based on which the Darcy's permeability was estimated. The permeability (kDL) of original floc was estimated as . Flocculated flocs had higher kDL due to their large pore size, while the corresponding values of kDL of the freeze/thawed flocs were lower. The calculated results indicate that a few large pores in the floc determine the permeability. The fractal dimension and compactness, however, are not correlated with the permeability of the flocs. 相似文献
994.
Gregory K. L. Goh Christine S. S. Tay Kelvin Y. S. Chan N. Gosvami 《Journal of Electroceramics》2006,16(4):575-579
Crystalline CeO2 films grown in aqueous solutions at 45∘C on glass slides formed by the island growth mode. The film had a refractive index of 1.83 and indicated that the film had
a porosity of 41.3%, which significantly lowered the elastic stiffness of the film. The film cracked only after drying in
a mud crack pattern when it reached a critical thickness. This indicated that the film cracked under tensile stress due to
the accumulation of tensile strains generated from grain coalescence during growth, thermal expansion mismatch during cooling
and capillary stress during drying. 相似文献
995.
We have compared the effects of sevoflurane and halothane on the discharge frequencies of 19 slowly adapting and four rapidly adapting lung receptors in the rabbit by recording from single vagal fibres. Both agents reduced the discharge frequency of slowly adapting receptors during expiration (P < 0.0005), halothane having a greater effect than sevoflurane (P < 0.0005). Neither agent had any effect on discharge frequency at the end of inspiration when discharge frequency is at a maximum. Neither agent affected the discharge frequency of rapidly adapting receptors. 相似文献
996.
OM Hanniffy AS Shashkov SN Senchenkova SV Tomshich NA Komandrova LA Romanenko YA Knirel AV Savage 《Canadian Metallurgical Quarterly》1998,307(3-4):291-298
An acidic O-specific polysaccharide was obtained by mild acid degradation of the lipopolysaccharide isolated by phenol-water extraction of Pseudoalteromonas haloplanktis strain KMM 223 (44-1). L-Iduronic acid (IdoA) was found to be a component of the polysaccharide and identified by NMR spectroscopy and after carboxyl-reduction followed by acid hydrolysis and acetylation, by GLC-MS as 2,3,4-tri-O-acetyl-1,6-anhydroidose. On the basis of 1H and 13C NMR spectroscopic studies, including 1D NOE, 2D NOESY, HSQC and HMBC experiments, the following structure of the branched pentasaccharide repeating unit of the polysaccharide was established: -->4)-beta-D-GlcpAI-(1-->4)-beta-D-GlcpAII-(1-->3)-beta-D-++ +QuipNHb4NHbII- (1-->2)-alpha-L-IdopA-(-->4 increases 1 alpha-D-QuipNAc4NAcI where QuiNAc4NAc and QuiNHb4NHb are 2,4-diacetamido-2,4,6-trideoxyglucose and 2,4,6-tri-deoxy-2,4- di[(S)-3-hydroxybutyramido]glucose, respectively. This is the first report of L-iduronic acid in a lipopolysaccharide and of D-QuiNHb4NHb in nature. 相似文献
997.
Few family therapists have expertise in the psychology of giftedness, and little research has been conducted to determine the effectiveness of family therapy with talented children and their families. The purposes of this paper are: (1) to provide family therapists with information on the unique psychosocial stressors associated with giftedness and (2) to stimulate further research and development on the efficacy of family therapy in alleviating distress and actualizing potential in gifted and talented children and their families. The paper provides a critical overview of the existing research literature on gifted children and their families. First, current conceptualizations of giftedness are described. Then the research literature on the characteristics of intellectually and creatively gifted children and their families is reviewed with an emphasis on the endogenous (individual) and exogenous (systemic) factors that can create or exacerbate psychosocial problems. Finally, we suggest an eclectic, eco-systemic approach to three common concerns that bring gifted children and their families to therapy. 相似文献
998.
Twenty-nine patients referred consecutively to a cancer clinic because of recurrent metastatic malignant melanoma were given 5 mg of Connaught Laboratories bacillus Calmette-Guérin (BCG) by multiple cutaneous puncture at weekly and later at monthly intervals. Eight were also treated with autologous tumour vaccine and three with intralesional BCG. This group was compared with a retrospective control group of 54 patients treated with surgery and radiotherapy alone after recurrence. Prognostic features such as site of primary and of first metastasis, disease-free interval, age and sex were similar in the two groups. However, the median survival from the time of first recurrence was 12 months in the control group but 21 months in the BCG-treated group. The major improvement was in patients with disease limited to the regional lymph nodes: the median survival was 16 months in the control group but over 32 months in the BCG-treated group. Autologous tumour vaccine appeared to have no effect on survival. Serial testing of immunocompetence did not offer any prognostic advantage, although the results of some tests correleated well with extent of disease. 相似文献
999.
1000.
Rouleaux are formed by the aggregation of red blood cells in the presence of macromolecules that bridge the membranes of adherent erythrocytes. We compute the size and degree of branching of rouleaux for macroscopic systems in thermal equilibrium in the absence of fluid flow. Using techniques from statistical mechanics, analytical expressions are derived for (a) the average number of rouleaux consisting of n cells and having m branch points; (b) the average number of cells per rouleau; (c) the average number of branch points per rouleau; and (d) the number of rouleaux with n cells, n = 1, 2, ..., in a system containing a total of N cells. We also present the results of numerical evaluations to establish the validity of asymptotic expressions that simplify our formal analytic results. 相似文献