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961.
Abstract: A 15‐year‐old male orally consumed an unknown but fatal amount of sustained release hydromorphone. He was naïve to opioid use. No other drugs or alcohol were involved. The cause of death was acute aspiration‐related bronchopneumonia, secondary to hydromorphone ingestion; the manner of death was accidental. Hydromorphone and hydromorphone‐3‐glucuronide were quantified in postmortem fluids by tandem liquid chromatography–mass spectrometry. The hydromorphone concentrations in the peripheral blood, urine, and vitreous humor were 57, 4460, and 31 ng/mL, respectively. The hydromorphone‐3‐glucuronide concentrations in the corresponding three fluids were 459, 36,400, and 40 ng/mL. Hydromorphone‐3‐glucuronide accumulation probably did not contribute significantly to the opiate toxicity. The proposed minimum lethal hydromorphone blood concentration in the nontolerant user is in the vicinity of 60 ng/mL.  相似文献   
962.
In estimating age of juveniles and adolescents, the teeth are employed primarily because of its low variability and less affection by endocrine and nutritional status in development. Demirjian established criteria for evaluating maturity of teeth and his method has been used throughout the world. However, several studies showed the inappropriateness of Demirjian's method on populations other than the one it is based on. Consequently some researchers modified Demirjian's method using data of several different populations. Demirjian himself also published a revised method to overcome other shortcomings of his original method. The aim of this study was to test the validity of Demirjian's and the modified methods (Demirjian's revised, Willems', Chaillet's and new Korean methods) for Korean juveniles and adolescents. 1483 digital orthopantomograms which consist of 754 males and 729 females in the age range of 3-16 years were collected. New age estimation method based on Korean population data was calculated. Dental age was estimated according to each method and the validity was evaluated using the differences between chronological and dental age. The inter- and intra-observer reliability was evaluated to be excellent. Statistically significant difference was observed between chronological and dental age in all the methods for both sexes except new Korean method for both sexes and Demirjian's revised method for males. However, when analyzing absolute and squared value of difference, Willems' method was found to be most accurate followed by new Korean method with slight difference for Korean population for both sexes. In conclusion, both Willems' method and new Korean method conducted by present study were proven to be suitable for Korean population.  相似文献   
963.
The quantitative analysis of 11-nor-D(9)-tetrahydrocannabinol-9-carboxylic acid (THCCOOH) in hair requires a sensitive method to detect a low-pg level. Before applying the method to real hair samples, the method was validated; in this study, we examined the uncertainty obtained from around the cut-off level of THCCOOH in hair. We calculated the measurement uncertainty (MU) of THCCOOH in hair as follows: specification of the measurand, identification of parameters using "cause and effect" diagrams, quantification of the uncertainty contributions using three factors, the uncertainty of weighing the hair sample, the uncertainty from calibrators and the calibration curve, and the uncertainty of the method precision. Finally, we calculated the degrees of freedom and the expanded uncertainty (EU). The concentration of THCCOOH in the hair sample with its EU was (0.60 ± 0.1) × 10(-4)ng/mg. The relative uncertainty percent for the measurand 0.60 × 10(-4)ng was 9.13%. In this study, we also selected different concentrations of THCCOOH in real hair samples and then calculated the EU, the relative standard uncertainty (RSU) of the concentration of THCCOOH in the test sample [u(r)(c0)], the relative uncertainty percent, and the effective degree of freedom (v(eff)). When the concentrations of THCCOOH approached the cut-off level, u(r)(c0) and the relative uncertainty percent increased but absolute EU and v(eff) decreased.  相似文献   
964.
In this study, we investigated the patterns of cannabis users (n=412) according to their sex, age, and the results of urinalysis and hair analysis, and classified the concentrations of THCCOOH in hair into three categories to examine the levels of cannabis use. We also compared the concentrations of THCCOOH in hair root, hair without the hair root and whole hair and examined the relationship among them according to the results of urinalysis. The hair samples were washed, digested with 1ml of 1M NaOH at 85°C for 30min and extracted with 2ml of n-hexane:ethyl acetate (9:1) two times after adding 1ml of 0.1N sodium acetate buffer (pH 4.5) and 200μl of acetic acid. The final mixture was derivatized with 50μl of PFPA and 25μl of PFPOH for 30min at 70°C. The solution was evaporated, and the residue was reconstituted in 40μl of ethyl acetate and transferred to an autosampler vial. One microlitre was injected into the GC/MS/MS-NCI system. The concentrations of THCCOOH ranged from 0.06 to 33.44pg/mg (mean 2.96; median 1.32) in hair from cannabis users who had positive urine results and ranged from 0.05 to 7.24pg/mg (mean 1.35; median 0.37) in hair from cannabis users who had negative urine results. The average concentration of THCCOOH in hair from cannabis users who had positive urine results was higher than that from cannabis users who had negative urine results. Male cannabis users in their forties were predominant. We classified the concentrations of THCCOOH in hair into three groups (low, medium and high), and could use the grouping of THCCOOH in hair as a guide for determining the level of use. The low, medium and high concentration ranges for THCCOOH in hair were 0.05-0.24, 0.25-2.60 and 2.63-33.44pg/mg, respectively. We also investigated 28 hair samples with the root. The highest concentrations of THCCOOH were seen in the hair root from 18 out of the 28 hair samples. The average concentrations of THCCOOH in hair root, hair without hair root and whole hair from cannabis users who had positive urine results were higher than those who had negative urine results.  相似文献   
965.
An investigation of a traffic accident involving a tractor-trailer and a passenger car that were traveling at high speed is presented. The cause was the fracture of a trailer axle. The investigation showed that the fracture was because of the fatigue failure. In addition, cracks were found in the remaining three trailer wheels. Hardness measurements showed that, because of inadequate heat treatment of the metal, they were prone to failure.  相似文献   
966.
Fiduciary law is in a state of flux. We know that the core obligationof a fiduciary is an obligation of loyalty, but we are lesssure what ‘fiduciary loyalty’ encompasses. We knowa fiduciary has duties not to profit or put himself in positionsof conflict, but how these duties interact with other non-fiduciaryduties (whether tortious or contractual or otherwise) is moredifficult to discern. Against this background, Conaglen hasmade a recent contribution to our understanding of the fiduciarydoctrine. He suggests that fiduciary loyalty offers a subsidiaryand prophylactic form of protection for non-fiduciary duties.This article considers his analysis, and argues that it is notsupported by case law and creates a number of inexplicable implicationsfor the fiduciary doctrine. In view of these difficulties, Conaglen'sanalysis should be rejected.  相似文献   
967.
We examined relationships between abuse, coping, and psychological health among 143 women who had experienced abuse in adult relationships. Measures included characteristics of the abuse, problem-focused and emotion-focused coping, Sense of Coherence, and four measures of psychological wellbeing--the SF-36 Mental Component Scale, the General Health Questionnaire, Center for Epidemiologic Studies Depression scale, and a measure of perceived negative effects of the abuse. Problem-focused coping was not related to psychological health, and the influence of emotion-focused coping on psychological health was indirect. Sense of coherence had significant direct effects on psychological health. Both emotion-focused coping and sense of coherence were related to aspects of the abusive experience. The concept of sense of coherence has parallels with the recently proposed concept of meaning-focused coping, and the data suggest that finding meaning in adverse events such as abuse is associated with better psychological well-being.  相似文献   
968.
Survey research is a common tool for assessing public opinions, perceptions, attitudes, and behaviors for analyses in many social science disciplines. Yet there is little knowledge regarding how specific elements of survey research methodology are applied in practice in public administration. This article examines five mainstream public administration journals over an eight‐year period regarding current methodological practice, organized around the total survey error framework. The findings show that survey research in the field of public administration features mainly small‐scale studies, heavy reliance on a single data collection mode, questionable sample selection procedures, and suspect sample frame quality. Survey data largely are analyzed without careful consideration of assumptions or potential sources of error. An informed evaluation of the quality of survey data is made more difficult by the fact that many journal articles do not detail data collection procedures. This study concludes with suggestions for improving the quality and reporting of survey research in the field.  相似文献   
969.
This article examines the relationship between electronic participation (e‐participation) and trust in local government by focusing on five dimensions of the e‐participationprocess: (1) satisfaction with e‐participation applications, (2) satisfaction with government responsiveness to e‐participants, (3) e‐participants’ development through the participation, (4) perceived influence on decision making, and (5) assessment of government transparency. Using data from the 2009 E‐Participation Survey in Seoul Metropolitan Government, this article finds that e‐participants’ satisfaction with e‐participation applications is directly associated with their development and their assessment of government transparency. The findings reveal that e‐participants’ satisfaction with government responsiveness is positively associated with their perceptions of influencing government decision making. Furthermore, there is a positive association between e‐participants’ perception of influencing government decision making and their assessment of government transparency. Finally, the article finds that there is a positive association between e‐participants’ assessment of government transparency and their trust in the local government providing the e‐participation program.  相似文献   
970.
A rapid and simple gas chromatography-mass spectrometry (GC-MS) method was developed and validated for the simultaneous detection and quantification of five psychotropic phenylalkylamines (amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, and norketamine) in toenails. After external decontamination, nail clippings were mechanically pulverized with a bead mill and then incubated in methanol under ultrasonication at 50°C for 1 h. The resulting solutions were evaporated to dryness, derivatized, and analyzed by GC-MS. The intra- and inter-day precisions were within 10.7% and 13.9%, respectively. The intra- and inter-day accuracies were -4.2% to 5.0% and -2.4% to 8.4%, respectively. Limits of detection and quantification for each analyte were lower than 0.024 and 0.08 ng/mg, respectively. The recoveries were in the range of 80.6-87.5%. The results indicated that the proposed method is a simple, rapid, accurate, and precise for quantification of five phenylalkylamines in nails. The method was successfully applied to the simultaneous detection and quantification of phenylalkylamines in nail samples of possible drug abusers.  相似文献   
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