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31.
Journal of Quantitative Criminology - We aim to test the applicability of crime pattern theory in an Indian urban context by assessing the effects of offender residence, prior offending locations...  相似文献   
32.
A rapid and sensitive determination of cannabinoids in urine is important in many fields, from workplace drug testing over toxicology to the fight against doping. The detection of cannabis abuse is normally based on the quantification of the most important metabolite 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THCA) in urine. In most fields THCA needs to be present at a concentration of exceeding 15 ng/mL before a positive result can be reported.The method described in this paper, combines a 4 min GC–MS/MS method with a fast sample preparation procedure using microwave assisted derivatisation in order to complete the quantification of THCA in urine in 30 min, using only 1 mL of urine.The method is selective, linear over the range 5–100 ng/mL and shows excellent precision and trueness and hence, the estimated measurement uncertainty at the threshold level is small. The method also complies with applicable criteria for mass spectrometry and chromatography. Therefore the method can be used for rapid screening and confirmatory purposes.  相似文献   
33.
Soil can play an important role in forensic cases in linking suspects or objects to a crime scene by comparing samples from the crime scene with samples derived from items. This study uses an adapted ED‐XRF analysis (sieving instead of grinding to prevent destruction of microfossils) to produce elemental composition data of 20 elements. Different data processing techniques and statistical distances were evaluated using data from 50 samples and the log‐LR cost (Cllr). The best performing combination, Canberra distance, relative data, and square root values, is used to construct a discriminative model. Examples of the spatial resolution of the method in crime scenes are shown for three locations, and sampling strategy is discussed. Twelve test cases were analyzed, and results showed that the method is applicable. The study shows how the combination of an analysis technique, a database, and a discriminative model can be used to compare multiple soil samples quickly.  相似文献   
34.

Objectives

The crime and place literature lacks a standard methodology for measuring and reporting crime concentration. We suggest that crime concentration be reported with the Lorenz curve and summarized with the Gini coefficient, and we propose generalized versions of the Lorenz curve and the Gini coefficient to correct for bias when crime data are sparse (i.e., fewer crimes than places).

Methods

The proposed generalizations are based on the principle that the observed crime concentration should not be compared with perfect equality, but with maximal equality given the data. The generalizations asymptotically approach the original Lorenz curve and the original Gini coefficient as the number of crimes approaches the number of spatial units.

Results

Using geocoded crime data on two types of crime in the city of The Hague, we show the differences between the original Lorenz curve and Gini coefficient and the generalized versions. We demonstrate that the generalizations provide a better representation of crime concentration in situations of sparse crime data, and that they improve comparisons of crime concentration if they are sparse.

Conclusions

Researchers are advised to use the generalized versions of the Lorenz curve and the Gini coefficient when reporting and summarizing crime concentration at places. When places outnumber crimes, the generalized versions better represent the underlying processes of crime concentration than the original versions. The generalized Lorenz curve, the Gini coefficient and its variance are easy to compute.
  相似文献   
35.
The aim of this five-wave longitudinal study of 923 early to middle adolescents (50.7% boys; 49.3% girls) and 390 middle to late adolescents (43.3% boys and 56.7% girls) is to provide a comprehensive view on change and stability in identity formation from ages 12 to 20. Several types of change and stability (i.e., mean-level change, rank-order stability, and profile similarity) were assessed for three dimensions of identity formation (i.e., commitment, in-depth exploration, and reconsideration), using adolescent self-report questionnaires. Results revealed changes in identity dimensions towards maturity, indicated by a decreasing tendency for reconsideration, increasingly more in-depth exploration, and increasingly more stable identity dimension profiles. Mean levels of commitment remained stable, and rank-order stability of commitment, in-depth exploration, and reconsideration did not change with age. Overall, girls were more mature with regard to identity formation in early adolescence, but boys had caught up with them by late adolescence. Taken together, our findings indicate that adolescent identity formation is guided by progressive changes in the way adolescents deal with commitments, rather than by changes in the commitments themselves.  相似文献   
36.
This study investigated age- and gender-specific associations between parental support and parental knowledge of the child’s whereabouts, on the one hand, and sexual experience and sexual health (the ability to have safe and pleasurable sexual experiences) on the other hand. A representative Dutch sample of 1,263 males and 1,353 females (aged 12–25 years), who had previously engaged in sexual intercourse, completed a questionnaire that included measures of these constructs. Both parental support and knowledge were positively associated with contraceptive use, social skills in sexual interactions, sexual satisfaction, and delay of sexual debut. Findings also revealed that the majority of correlations between parental support and sexual experience and sexual health are attributable to the relationship between a supportive family environment and parental knowledge of the child’s whereabouts. Parental knowledge thus appeared to be more important for healthy sexual development than parental support.  相似文献   
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38.
Higher self-concept clarity is related to several adjustment indices and may be promoted by open communication with parents, while problems with self-concept clarity development could enhance internalizing problems (i.e., depressive and anxiety symptoms) in adolescence. This longitudinal study examined linkages between self-concept clarity, adolescents’ open communication with parents, and adolescent depressive and anxiety symptoms. Dutch youths (N = 323; 51.1 % girls; mean age Time 1 = 13.3 years) reported on these constructs over four consecutive annual measurements. Concurrent positive links between open communication and self-concept clarity were found at Time 1. Over time, higher levels of open communication with parents predicted higher self-concept clarity only in middle adolescence (mean age between 14 and 15 years). We also found concurrent associations between self-concept clarity and both depressive and anxiety symptoms. Longitudinally, lower self-concept clarity predicted relatively higher levels of depressive symptoms across all waves, and also higher anxiety levels from Time 1 to Time 2. Conversely, higher levels of anxiety also predicted lower levels of self-concept clarity during the first three waves. Self-concept clarity did not mediate the longitudinal associations between open communication and internalizing symptoms. This study is one of the first to investigate self-concept clarity across adolescence. It highlights the possible importance of both anxiety symptoms and communication with parents in understanding the development of a clear self-concept, and demonstrates an association between lower self-concept clarity and higher levels of later depressive and anxiety symptoms.  相似文献   
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40.
Adolescents at-risk for problem behaviors can have more difficulties in developing a firm sense of personal identity. Hence the purpose of this prospective longitudinal study was to scrutinize how externalizing problems in early adolescence impact identity development in middle to late adolescence. Participants were 443 (43.12 % female) Dutch adolescents. Teachers rated their externalizing problem behaviors when participants were 11 or 12 years old and their identity formation was studied during five consecutive years (from 14 to 18 years of age). The sample was divided into four groups: boys and girls with a high versus a low-risk for externalizing problem behaviors. Participants completed a self-report measure of identity commitment, in-depth exploration, and reconsideration of commitment. Multi-group Latent Growth Curve and profile stability analyses were used to evaluate identity development across adolescence. Findings indicated that high-risk boys and girls reported a less structured identity, with lower levels of commitment and higher levels of reconsideration of commitment. Since externalizing problems behaviors and lack of a coherent sense of identity might reinforce each other, early intervention for high-risk adolescents might foster positive youth development.  相似文献   
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