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491.
This study compares ex ante estimates of the direct costs of individual regulations to ex post assessments of the same regulations. For total costs the results support conventional wisdom, namely that the costs of regulations tend to be overestimated. This is true for 14 of the 28 rules in the data set discussed, while for only 3 rules were the ex ante estimates too low. For unit costs, however, the story is quite different. At least for EPA and OSHA rules, unit cost estimates are often accurate, and even when they are not, overestimation of abatement costs occurs about as often as underestimation. In contrast, for those rules that use economic incentives, unit costs are consistently overestimated. The difference between the total‐cost and the unit‐cost results is caused by frequent errors in estimates of the effects of individual rules, which suggests, in turn, that the rule's benefits may also be overestimated. The quantity errors are driven both by difficulties in determining the baseline and by incomplete compliance. In cases of unit‐cost overestimation, unanticipated technological innovation appears to be an important factor — especially for economic incentive rules, although procedural and methodological explanations may also apply. © 2000 by the Association for Public Policy and Management.  相似文献   
492.
The effects of dose–death interval on the detection of acute fentanyl exposure in fresh and decomposed skeletal tissues (marrow and bone), by automated enzyme-linked immunosorbent assay (ELISA) are described. Rats (n = 14) were administered fentanyl acutely at a dose of 0 (n = 2) or 60 μg/kg (n = 12) by intraperitoneal injection, and euthanized within 20, 45, 135, or 225 min. Femora and tibiae were extracted from the fresh corpses and marrow was isolated from the femoral and tibial medullary cavities. The remains were then allowed to decompose outdoors to the point of complete skeletonization, and vertebrae, pelvi and miscellaneous (humeri and scapulae) were recovered for analysis. In all cases, bones were cleaned in alkaline solution and then ground into a fine powder. Marrow was homogenized in alkaline solution. Fentanyl was extracted from ground bone by methanolic extraction. Extracts were adjusted to pH 6 and analyzed by ELISA. Perimortem heart blood was also collected and diluted in phosphate buffer prior to screening by ELISA. The effect of tissue type on ELISA response was examined through determination of binary classification test sensitivity and the relative decrease in absorbance (%DA, drug-positive tissues vs. drug-free controls) in each tissue type. Overall, the %DA varied significantly between extracts from different skeletal tissues at a given dose–death interval, according to the general order of marrow > decomposed bone > fresh bone. Binary classification test sensitivity values for fentanyl in marrow, fresh epiphyseal (femoral and tibial) bone, fresh diaphyseal (femoral and tibial) bone, decomposed vertebrae, decomposed pelvic bone, and decomposed miscellaneous bone were 67–100%, 0–33%, 0–33%, 0–67%, 0–67% and 0–33%, respectively, over all dose–death intervals. Although group mean %DA values showed a strong negative correlation with dose–death interval in marrow, fresh epiphyseal bone, decomposed vertebrae, pelvic and miscellaneous bone (r = ?0.989, ?0.930, ?0.955, ?0.903, and ?0.974, respectively), the high variability in both fresh and decomposed bone precluded differentiation of the dose–death intervals based on %DA value alone. Overall, the results suggested that the type of skeletal tissue sampled may not be as important as the amount of residual marrow remaining in skeletonized remains.  相似文献   
493.
494.
Recent evidence suggests parent-adolescent discrepancies regarding adolescent disclosure can provide insight into parent-child relations and adolescent adjustment. However, pathways linking discrepancies to adjustment are not well known. We tested a model linking parent-adolescent discrepancies in disclosure to adolescent substance use through affiliation with deviant peers. Using three annual waves of data from a community-based study (N?=?357; 91% African American; 53% female; Mage?=?13.13 years, SD?=?1.62 years at baseline), findings revealed that adolescent-reported secrecy and deviant peer affiliation were positively associated with substance use one and two years later, respectively, but there was no evidence of mediation. The results highlight associations of adolescent secrecy and adjustment, and the role peers play in adolescent substance use behaviors.  相似文献   
495.
One of the most common motifs surrounding sports, sports teams, and sports stars is “the scandal.” One typifying feature of mediated scandals is the ease with which they can be presented as, or massaged into, an unfolding narrative. Although some research has been conducted into the initial stages of these narratives, there is significantly less that focusses on the ways in which the “transgressor” can be rehabilitated in a separate but linked part of that overarching story. This article addresses that gap by analysing two television commercials that significantly assisted the Melbourne Storm rugby league franchise in encouraging and maintaining identification and, coterminously, overcoming disidentification with its membership. Furthermore, we contend that the Melbourne Storm purposively used rhetorical strategies to emphasise the socially desirable aspects of its identity to repair damage done to its organisational image. Using rhetorical analysis, the article explicates the various techniques through which this was accomplished.  相似文献   
496.
497.
This study evaluated psychometric properties of the Timeline Followback interview—Children’s Exposure to Partner Violence (TLFB-CEPV), an event history calendar interview designed to assess children’s exposure to daily patterns of intimate partner violence. Participants were men (N = 107) entering batterer’s treatment, their female partners, and a custodial child (6–16 years). The TLFB-CEPV asked about days of partner physical aggression and children’s exposure to these episodes, and was administered to partners at pretreatment, posttreatment, 6 and 12 months. At each assessment, the percentage of days of any child exposure (PAE) and of children’s direct exposure (PDE) to violence were calculated. Parents completed measures of partner aggression and social desirability; parents, teachers, and children completed measures of children’s adjustment. TLFB-CEPV scores had excellent temporal stability and strong evidence of concurrent, discriminant, and criterion validity. Interrater agreement for TLFB-CEPV scores was moderate at initial assessment, but high at subsequent follow-up interviews. This project was supported, in part, by grants from the National Institute on Drug Abuse (R01DA12189, Fals-Stewart), the Alpha Foundation, and Old Dominion University.  相似文献   
498.
The identification of forensically important blowflies of the genus Chrysomya (Diptera: Calliphoridae) may be hampered by their close morphological similarities, especially as immatures. In contrast to most previous studies, the utility of a nuclear rather than mitochondrial genetic marker was investigated to solve this problem. The second internal transcribed spacer (ITS2) of ribosomal DNA (rDNA) was amplified and sequenced from all nine Chrysomya species known from Australia. Difficulties encountered with direct sequencing of ITS2 for Chrysomya flavifrons necessitated cloning prior to sequencing for this species, which revealed a low level (0-0.23%) of intraindividual variation. Five restriction enzymes (DraI, BsaXI, BciVI, AseI and HinfI) were identified that were able to differentiate most members of the genus by polymerase chain reaction (PCR) restriction fragment length polymorphism (PCR-RFLP). The PCR-RFLP analysis revealed characteristic restriction profiles for all species except the closely related species pairs Chrysomya latifrons+Chrysomya semimetallica and Chrysomya incisuralis+Chrysomya rufifacies. Ch. incisuralis and Ch. rufifacies were able to be separated using the size differences resulting from amplification of the entire ITS region. The lack of intraspecific ITS2 sequence variation among eight Ch. incisuralis specimens was verified by the identical restriction profiles generated from these specimens. A DNA-based approach, such as PCR-RFLP, has the capacity to be useful for the identification of forensic entomological evidence in cases where morphological characters are unreliable.  相似文献   
499.
500.
Filial piety has remained a cornerstone of aged care in Chinese communities for at least 2,000 years. This paper reviews understandings and practices of filial piety in China and among Chinese migrants to western countries. Five dimensions of filial piety are considered: living arrangements, support, respect, ancestral worship and gender norms. Although the meaning of and practices associated with filial piety may have changed over time, the ideal of filial piety is still highly relevant to aged care in Chinese communities today.  相似文献   
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