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51.
A simple method for analyzing nitrite in urine has been developed to confirm and quantify the amount of nitrite in potentially adulterated urine samples. The method involved separation of nitrite by capillary electrophoresis and direct UV detection at 214 nm. Separation was performed using a bare fused silica capillary and a 25 mM phosphate run buffer at a pH of 7.5. Sample preparation consisted of diluting the urine samples 1:20 with run buffer and internal standard, and centrifuging for 5 min at 2500 rpm. The sample was hydrodynamically injected, then separated using -25 kV with the column maintained at 35 degrees C. The method had upper and lower limits of linearity of 1500 and 80 microg/mL nitrite, respectively, and a limit of detection of 20 microg/mL. The method was evaluated using the National Committee for Clinical Laboratory Standards (NCCLS) protocol (Document EP10-A2), and validated using controls, standards, and authentic urine samples. Ten anions, ClO-, CrO4(-2), NO3-, HCO3-, I-, CH3COO-, F-, SO4-, S2O8(-2), and Cl-, were tested for potential interference with the assay. Interferences with quantitation were noted for only CrO4(-2) and S2O8(-2). High concentrations of Cl- interfered with the chromatography. The method had acceptable accuracy, precision, and specificity.  相似文献   
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Frequency of analytical characteristics is best estimated on glass recovered at random. However, as such data were not available to us, we decided to use control windows for this estimation. In order to use such a database, one has to establish that the recovered fragment comes from a window. Therefore, elemental analysis was used both for classification and discrimination of glass fragments. Several articles have been published on the subject, but most methods alter the glass sample. The use of non destructive energy dispersive X-ray microfluorescence (microXRF) for the analysis of small glass fragments has been evaluated in this context. The refractive index (RI) has also been measured in order to evaluate the complementarity of techniques. Classification of fragments has been achieved using Fisher's linear discriminant analysis (LDA) and neural networks (NN). Discrimination was based on Hotelling's T2 test. Only pairs that were not differentiated by RI followed by the Welch test were studied. The results show that neural network and linear discriminant analysis using qualitative and semi-quantitative data establishes a classification of glass specimens with a high degree of reliability. For discrimination, 119 windows collected from crime scene were compared: using RI it was possible to distinguish 6892 pairs. Out of 129 remaining pairs, 112 were distinguished by microXRF.  相似文献   
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Supraphysiologic doses of testosterone are associated with increased aggression that is hypothesized to be a function of testosterone serum concentrations, mood, and personality. The study attempted to characterize this relationship among weightlifters who were users (n = 10) and nonusers (n = 18) of anabolic steroids. Participants were interviewed using the Modified Mania Rating Scale and Hamilton Rating Scale for Depression to assess mood, the Buss-Durkee Hostility Inventory (BDHI) and Point Subtraction Aggression Paradigm (PSAP) to assess aggression, and the Personality Disorder Questionnaire (PDQ-R) to assess personality. Blood samples were obtained for the determination of total, free, and weakly bound testosterone. Comparisons of continuous variables between testosterone users and non-users were performed with a parametric (unpaired t-test) or non-parametric (Mann-Whitney) test where appropriate. Correlations with testosterone were examined separately for testosterone users and non-users, using Spearman rank correlation. The subjective (BDHI) and objective (PSAP) assessments of aggression found that supranormal testosterone concentrations were associated with increased aggression. However, the PDQ-R results suggest that this finding was confounded by the personality disorder profile of the steroid users, because steroid users demonstrated Cluster B personality disorder traits for antisocial, borderline, and histrionic personality disorder.  相似文献   
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The Strategic Use of Evidence (SUE) approach is a framework for planning and executing suspect interviews with the aim of facilitating judgments of truth and deception. US law enforcement officers (N = 59) either received training in the SUE approach or did not. Each officer interviewed a mock suspect (N = 59) who had either committed a simulated security breach or had completed a benign task. The officers who received SUE training interviewed in line with the training: They questioned the suspect systematically, withheld the evidence and critical case information until after questioning, and relied on statement-evidence inconsistency to detect deceit. Consequently, SUE-trained interviewers achieved a higher deception detection accuracy rate (65%) compared to untrained interviewers (43%).  相似文献   
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This article offers an interpretation of the present conflictin Ituri based on social analysis. Other than the conventionalaccounts which depart from the presence of foreign troops onCongolese soil, reduce the war to a struggle for natural resourcesor see it as the result of age-old ethnichatreds, the authorstry to place this conflict into its social setting. The centralargument of this article is that the outbreak of violence inIturi has been the result of the exploitation, by local andregional actors, of a deeply rooted local political conflictfor access to land, economic opportunity and political power.Firstly, it is assumed that the destruction of the local socioeconomicfabric and the emergence of ethnicity as the main basis forpolitical mobilization has been the result of a long historicalprocess in which access to land, education, political positionsand economic dominance have played a crucial role. Secondly,it is asserted that, although foreign elements (i.e. the UPDFand RDF, formerly RPA) have contributed significantly to theescalation of the political crisis in Ituri, the war has alsoprovided a perfect platform for local political and economicactors to redefine their position in this new political andeconomic landscape. Eventually, this emerging political complexhas led to the development of a new political economy whichis characterized by a shift from traditional to military rule,to privatized, non-territorial networks of economic control,and to the consolidation of ethnic bonds in the economic andpolitical sphere.  相似文献   
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