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61.
Prospects for redeveloping the older areas of cities for residential use depend largely upon the extent to which consumers prefer central rather than outlying locations for new housing. The strength of the downtown core, the regional transportation system, and the proximity of vacant land influence this preference. Empirical studies of new housing in three contrasting regions provide a means of evaluating the importance of these factors and their effects upon rents, densities, and vacancy rates at central and outlying locations.  相似文献   
62.
Abstract

An equation has been developed to relate the viscosity of unbleached pulp to the residual alkali in the spent liquor, and the time-temperature profile of the cook (expressed as the G-factor). The equation is applicable to kraft, kraft-AQ and soda-AQ pulping and to a variety of wood species.  相似文献   
63.
The Wolf–Broad oxbow lake (417 ha) was evaluated by the Mississippi Department of Environmental Quality and included on the Mississippi 303(d) list of impaired waterbodies for total suspended solids (TSS). A study was undertaken for 2 years to evaluate and document changes to TSS (mg L?1) and overall lake turbidity (NTU) through best management practice implementation. These two objectives were analysed with routine monthly surface sampling events of turbidity (Eureka Manta 2, automated data sonde) as well as 20 random samples per sampling trip for TSS from June 2008 to June 2010. Results from a non‐parametric Kruskal–Wallis analysis indicated a significant month‐by‐year effect on turbidity and TSS (chi‐squared = 76.08, p = 0.001), but reach (chi‐squared = 2.45, p = 0.784) and depth by reach (chi‐squared = 2.44, p = 0.784) did not show significant effects on turbidity. There were no significant correlations between TSS concentrations and turbidity and 2 days and 7 days summed or mean rainfall for the duration of the evaluation. Spearman correlation analysis for TSS indicated significant correlations between TSS and mean two‐day (r2 = 0.62, p = 0.002) and seven‐day (r2 = 0.51, p = 0.014) wind speeds. All other variables used in the analysis did not show significant correlation with TSS ( p > 0.05). This suggests that wind conditions, rather than rainfall, predict the greatest variability in TSS and turbidity in Wolf Lake. These documented correlations between lake water column TSS, turbidity and wind highlight the difficulties of demonstrating success of management practices in the short temporal period between project initiation and completion. Unmanageable environmental conditions (wind speed and direction) and limited temporal monitoring scales (1 1/2 years post‐BMP implementation) limit the possibility of demonstrating successful water‐quality improvement within a 303(d) listed waterbody such as Wolf Lake. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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The psychometric characteristics of the Center for Epidemiologic Studies Depression Scale (CES–D) were investigated with American Indian boarding school students (N?=?188; Grades 9–12). The CES–D showed good internal consistency (α?=?.82). Its dimensional structure was different from that described for adults, both Indian and non-Indian. Of the Indian students, 58% were classified as depressed, using the standard cutoff score of 16 or more, consistent with past studies of this age group. Alternative scoring methods were considered, based on persistence of symptoms as well as derived Diagnostic and Statistical Manual of Mental Disorders (DSM-III) and Research Diagnostic Criteria algorithms. Major gender differences were observed in the prevalence of reported symptoms as well as patterns of endorsement for certain CES–D items. The CES–D should be used with caution with American Indian adolescents, given the observed variation in its dimensional structure and uncertainty regarding appropriate cutoff scores. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
66.
This study investigated the effects of early-rearing experiences on responsiveness to pups and on the pattern of c-fos activation in the brain of juvenile female rats. From Days 4 to 20, littermate females were reared with their mothers (MR) or artificially (AR). AR rats received minimal licking-like tactile stimulation (AR-min) or maximal stimulation (AR-max). On Day 20, rats were exposed to pups for 4 or 8 days, exposed to a playmate for 4 or 8 days, or left in isolation for 4 or 8 days. Compared with MR rats, pup-exposed AR rats engaged in less pup licking, and all AR rats showed significant reductions in c-fos immunoreactivity in the medial preoptic area and the parietal and piriform cortices. The AR-min group showed the greatest difference in Fos-lir compared with the MR groups. Possible mechanisms that mediate the effects of rearing on the development of neural circuits underlying maternal behavior are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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68.
A diode-laser pumped multitransverse-mode neodymium-doped fluoride fiber laser is shown to oscillate in the lowest-order transverse mode when the cavity conditions are optimized. The combination of good pump coupling efficiency, laser operating efficiency, and good overlap of the HE11 mode to that of a single-mode fiber, allows up to 12 mW of continuous wave (CW) power to be coupled into a standard single-mode fiber at a 1345-nm wavelength. Improved lens design should significantly increase the power injected into the single-mode fiber from the multimode fiber laser  相似文献   
69.
PURPOSE: We evaluated the clinical use of long-term intravesical oxybutynin chloride in the treatment of neurogenic bladder dysfunction in children with myelodysplasia who could not tolerate oral anticholinergics. MATERIALS AND METHODS: We retrospectively reviewed the records of all patients recommended for intravesical oxybutynin chloride therapy. A total of 12 girls and 18 boys 1 to 17 years old was recruited for study. Oxybutynin chloride (5 mg.) was instilled 2 times daily and pretreatment cystograms were compared to followup urodynamic studies. Duration of therapy was 2 to 26 months (mean 13, median 12). RESULTS: Mean total capacity plus or minus standard deviation increased from 209 +/- 103 to 282 +/- 148 ml. (p < 0.01), mean safe capacity increased from 157 +/- 105 to 234 +/- 147 ml. (p < 0.01) and mean age adjusted safe capacity increased from 76 +/- 36 to 115 +/- 62%. Of the 29 patients who were incontinent 3 (10%) achieved continence and 19 (65%) reported a decreased use of sanitary pads. None of the patients had systemic side effects related to intravesical treatment. CONCLUSIONS: We believe that intravesical oxybutynin chloride is a viable treatment option for patients with myelodysplasia in whom oral therapy fails.  相似文献   
70.
New techniques for modifying the surface of ink-jet papers are continuously being developed. The affordability of ink-jet printers has placed them in the forefront of home-use for digital printing technology. Thus, there is a demand on the paper substrate, whether coated or not, to respond to a variety of ink-jet operating conditions, while continuing to yield a product with high print quality. Coating formulations for ink-jet papers currently utilize precipitated or gelled silica with polyvinyl alcohol (PVOH) as the binder. This silica and PVOH formulation generates good optical, surface, and print qualities, yet leaves a lot to be desired from a runnability and coating preparation standpoint. The modified clay pigment offers potential as a substitute particle for the silica pigment in matte grades of ink-jet paper. The modified clay pigment offered significant improvements in coating preparation and runnability. The modified clay, however, could not match silica in producing the surface and bulk coating properties required for generating high print quality without the addition of a cationic additive. Presented at the 79th Annual Meeting of the Federation of Societies for Coatings Technology, Nov. 5–7, 2001, in Atlanta, GA. Dept. of Paper and Printing Science and Engineering, College of Engineering and Applied Sciences, Welborn Hall, Kalamazoo, MI 49008-5362.  相似文献   
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