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231.
Four multi-elementary metal and metalloid quantification methods using inductively coupled plasma mass spectrometry (ICP-MS) were developed and validated in human whole blood, plasma, urine and hair by means of a single preparation procedure for each sample. The ICP-MS measurements were performed using a Thermo Elemental X7CCT series and PlasmaLab software without a dynamic reaction cell. With this procedure 27-32 elements can be simultaneously quantified in biological matrices: Li, Be, B, Al, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Mo, Pd, Ag, Cd, Sn, Sb, Te, Ba, W, Pt, Hg, Tl, Pb, Bi, U. Whole blood, plasma and urine samples (0.4 ml each) were diluted with purified water, acid, triton X100 and butanol. Rhodium was used as internal standard. The urine sample results were corrected for enzymatic creatinine determination. Twenty-five milligrams hair samples were acid mineralized after a decontamination procedure and diluted as previously described for biological fluids. To be validated, each element had to show linearity with a correlation coefficient higher than 0.99. The intra-assay and inter-assay inaccuracy, measured as the variation coefficient, were below 5 and 10% respectively. Global performance was assessed by a quality control program. Our laboratory is a registered participant of the Institut National de Santé Publique du Québec (Sainte-Foy, Canada) inter-laboratory comparison program for whole blood, urine, and beard hair of non-occupationally exposed individuals spiked with selected elements. In our study multi-element metal and metalloid analysis was assessed for 27 elements in whole blood, 27 elements in plasma, 30 elements in urine and 32 elements in hair, from 0 to 25, or 250 to 1000 ng/ml, depending on the element. Quantification limits ranged from 0.002 ng/ml (U) to 8.1 ng/ml (Al) for whole blood, from 0.002 ng/ml (U) to 7.7 ng/ml (Al) for plasma, from 0.001 ng/ml (U) to 2.2 ng/ml (Se) for urine, and from 0.2 pg/mg (Tl) to 0.5 ng/mg (B) for hair. Normal values were determined in whole blood (n=100), plasma (n=100), urine (n=100), and hair (n=45) of healthy volunteers, leading to approximately 10,000 analyses. All results are presented and discussed. Clinical toxicology and forensic toxicology applications are also reported. ICP-MS has made significant advances in the field of clinical biology, particularly in toxicological analysis. This is due to the use of extremely effective equipment that permits better clinical and forensic toxicological analysis of metal and metalloid status of each individual patient.  相似文献   
232.
A qualitative and quantitative analytical method was developed and validated for the determination of 49 licit and illicit drugs in oral fluid. Small oral fluid samples, volume 1mL, were collected from volunteers using a modified Omni-Sal device and the analytes were extracted from an oral fluid/buffer mixture using a single Bond Elut Certify solid phase extraction cartridge. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) and gas chromatography-repetitive full scan mass spectrometry (GC-MS) were used in parallel to analyze the extracts for the targeted drugs. Extracts were analyzed by GC-MS in their underivatized form and as their pentafluoropropionyl derivatives. Deuterated internal standards were used for quantification of drugs of abuse by LC-MS-MS to minimize matrix effects. Methadone-d(9) and tumoxetine were used as the internal standards for quantification of non-derivatized and derivatized analytes respectively by GC-MS. Linearity was demonstrated over the range 5-200 ng/mL and limits of detection were less than 4 ng/mL for each drug analyzed. The method demonstrated acceptable recoveries for most of the analytes and good intra- and inter-day precision. Acquisition of data by repetitive full scan GC-MS allows the addition of further analytes to the target menu.  相似文献   
233.
In the spring of 2003, bush cutters discovered a large grain bag filled with human skeletal remains in a forest in South Africa. Differential taphonomic processes observed on the bones suggested that the individuals had not died at the same time or had decomposed under different circumstances. The remains were sorted using gross morphological techniques which included assessing the number of skeletal elements present, visual pair matching, articulation, process of elimination and taphonomy. Standard techniques were used to estimate age, sex, racial affinity and stature. A minimum number of individuals (MNI) of 10 was established, which included 7 adult males, 1 adult female and 2 juveniles. Trauma was observed on only one individual. Approximately, 80% of the skeletal remains were missing. These various skeletal elements may have been lost by accident, normal taphonomic processes or taken by scavengers. Possible origins for these skeletal remains include removal from a formal grave, found in the veldt or murdered.  相似文献   
234.
Prevention science has produced information about risk and protective factors that predict adolescent drug use and related problem behaviors. This paper investigates the Communities That Care Youth Survey that measures multiple risk and protective factors. Using a sample of 172,628 students who participated in surveys administered in seven states in 1998, analyses were conducted to test the factor structure of these risk and protective factors and to test the equivalence of the factor models across five racial/ethnic groups (African Americans, Asians or Pacific Islanders, Caucasians, Hispanic Americans, and Native Americans), four grade levels (6th, 8th, 10th, and 12th) and both gender groups. Results support the construct validity of the surveys risk and protective factor scales and indicate that the measures are equally reliable across males and females and five racial/ethnic groups. Implications of these findings for science-based prevention planning are discussed.  相似文献   
235.
236.
This study addresses the as yet unaddressed question of the nature of the effects of religiosity and authoritarianism upon endorsement of abstract democratic values. Findings obtained through the analyses of structural equations show that, despite the unsettled political and security atmosphere, Israelis believe in democratic values to a considerable extent. Furthermore, findings do not fully support the theoretical expectation that religiosity is likely to decrease support for democratic values; namely, in and of itself, religiosity has a negligible impact on endorsement of democratic values. Yet again, analyses lend credence to theory on authoritarianism—the negative effect of religiosity on endorsement of democratic values results from the mediation of authoritarianism. These findings are understood and discussed with regard to theoretical implications. The major conclusion, then, in contrast to existing assumptions regarding religiosity and negation of democracy linkage, is that religiosity cannot be considered the sole direct root cause of negation of democracy.  相似文献   
237.
The importance of the relation between impulsivity and deviance is well-acknowledged among criminologists. However, differences in the representations of impulsivity, some merely titular and others substantive, may cloud our understanding of these relations. The current study examines the argument, offered by Whiteside and Lynam Pers. Individuals Diff. (2000) 30: 669–689, that there may be four distinct personality pathways through which impulsive behavior may be manifested. Across three samples (two undergraduate, one community), we examine the validity of a four-factor structure of impulsivity, test whether these four pathways manifest divergent relations with various forms of deviant behavior such as crime and substance use, as well as laboratory manifestations of aggressive and impulsive behavior, and examine the invariance of these results across gender. The results support the existence of a four-factor model of impulsivity, the importance of two specific personality pathways in relation to self-reports of deviance (lack of premeditation and sensation seeking), as well as actual behavior, and suggest that these pathways are important for both men and women.  相似文献   
238.
Police officers are the only professionals mandated by society to use discretionary coercive physical force as a necessary component of fulfilling their duty to maintain public safety and uphold the law. If community policing is to prevail as an effective and credible style of law enforcement, the legitimate use of competent police authority will continue to be a vital issue. This article analyzes the types of officer problems and problem officers that can harm community policing efforts. These include (1) individual factors, such as attitudes, personality traits, and psychological disorders; (2) police-citizen interaction factors, such as interpersonal dynamics and community attitudes; and (3) organizational factors, such as training and supervision, departmental philosophy, and the “cop culture.” The article then offers practical strategies for improving officer performance, including (1) selection and screening of officers; (2) training and supervision; (3) fitnessfor-duty evaluations; (4) effective supervision and discipline; (5) coaching and counseling strategies; and (6) the most productive use of psychological services. Throughout this discussion, the concept of the police officer as a law enforcement professional is emphasized as essential for guiding public safety policy into the 21st century.  相似文献   
239.
The present study investigated the possibility of statistically linking arson cases based on consistency of behaviors from one crime scente to another. Serial and spree arson cases were studied to differentiate underlying themes and to link cases committed by the same offender. The material consisted of 248 arson cases which formed 42 series of arsons. A content analysis using 45 dichotomous variables was carried out and principal compnents (PCA) analysis was performed to identify underlying themes. Summary scores reflecting the themes were calculated. Linking effectiveness was tested with a discriminant analysis using the summary scores. The PCA analysis was successful and underlying themes which were in accordance with previous studies could be identified. Six factors were retained, in the PCA. The linking of the arson cases was possible to a satisfactory level: 33% of the cases could be correctly linked and for over 50% of the cases, the series they actually belonged to was among the ten series identified as most probable on the basis of the linking analysis. From a practical point of view, the results could be used as a basis for developing support systems for police investigations of arson. This research was financially supported by the Finnish Ministry of Interior and by Grant 54456 from the Academy of Finland.  相似文献   
240.
This study reports an analysis of Bartol's (1991) Immaturity Index and Hargrave and associates' (1988) Aggressiveness Index as a measure of police conduct. The correlations between the supervisory ratings and the Immaturity and Aggressiveness indices were examined for 1020 law enforcement officers. The results showed that Immaturity Index was related to termination for failure to complete training and insubordination. The Aggressiveness Index was related to a termination for failure to complete training and several other problematic police behaviors, but was not found to be specifically linked with acts of aggression. Implications for using these two indices in law enforcement selection are discussed. Authors' Note: Cary Rostow, Ph.D. is president of Matrix, Inc., Baton Rouge, Louisiana, and is in private practice in Baton Rouge. Robert Davis, Ph.D., is executive vice-president and director of science, research, and development for Matrix, Inc., and has a private practice in Baton Rouge. James B. Pinston, Ph.D., is a clinical neuropsychologist within the department of neurology at the Louisiana State University Health Sciences Center and School of Medicine in Shreveport, Louisiana. Dennis R. Combs, Ph.D., is an assistant professor of psychology at the University of Tulsa. Dennis R. Dixon, M.A., is currently a doctoral student at Louisiana State University.  相似文献   
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