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191.
Although the topic of recidivism invariably elicits much interest, there appears to be considerable conflict and uncertainty as to even crude estimates of the recidivism rate for persons released from prison. The purpose of this research was to examine the extent to which this apparent confusion may be explained by different methodological choices of criterion measure or length of follow-up. Through the cooperation of the Federal Bureau of Investigation, rap sheet follow-up information for a six-year period was obtained for a relatively large random sample of federal prisoners released in 1970. This data enabled calculation of recidivism rates using various criterion measures and follow-up periods applied to the same sample. The effect of varying these definitions on the recidivism rate obtained can then be directly observed. 相似文献
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193.
Schneider PM Bender K Mayr WR Parson W Hoste B Decorte R Cordonnier J Vanek D Morling N Karjalainen M Marie-Paule Carlotti C Sabatier M Hohoff C Schmitter H Pflug W Wenzel R Patzelt D Lessig R Dobrowolski P O'Donnell G Garafano L Dobosz M De Knijff P Mevag B Pawlowski R Gusmão L Conceicao Vide M Alonso Alonso A García Fernández O Sanz Nicolás P Kihlgreen A Bär W Meier V Teyssier A Coquoz R Brandt C Germann U Gill P Hallett J Greenhalgh M 《Forensic science international》2004,139(2-3):123-134
Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak height and balance as well as the occurrence of artefacts. A number of common problems were identified based on these results such as strong peak imbalance in heterozygous genotypes for the larger short tandem repeat (STR) fragments after increased PCR cycle numbers, artefact signals and allelic drop-out. Based on the observations, strategies are discussed to overcome these problems. The strategies include careful balancing of the amount of template DNA and the PCR cycle numbers, the reaction volume and the amount of Taq polymerase. Furthermore, a careful evaluation of the results of the fragment analysis and of automated allele calling is necessary to identify the correct alleles and avoid artefacts. 相似文献
194.
195.
Der Beitrag geht der Frage nach, wie national unterschiedliche politökonomische Institutionen die Leistungskraft entwickelter Marktwirtschaften beeinflussen und ob institutionelle Komplementaritäten in der Makroökonomie existieren. Der Ansatz der ?Spielarten des Kapitalismus“ behauptet, dass es diese Komplementaritäten gibt und sich die Länder entsprechend dem in den ökonomischen Sphären vorherrschenden Modus der Koordination in klare Gruppen unterscheiden lassen. In dem Artikel werden die Kernaussagen des Ansatzes einer Reihe von empirischen Tests unterzogen, die auf einer zusammenfassenden Analyse einer Reihe von Fallbeispielen beruht, Die empirischen Ergebnisse bestätigen die Annahmen in überzeugender Weise. Dieliberalen undkoordinierten Marktwirtschaften variieren systematisch entsprechend dem relativen Verhältnis zwischen marktförmiger und strategischer Koordination. Institutionelle Komplementaritäten finden sich in beiden Typen, und sie bringen gesamtwirtschaftliche Leistungszuwächse hervor. Abschließend werden die Muster des institutionellen Wandels in den entwickelten politischen Ökonomien analysiert und einige politische Implikationen der Befunde diskutiert. 相似文献
196.
The purpose of this study was to evaluate the ability of two amphetamine class screening reagents to exclude ephedrine (EPH), pseudoephedrine (PSEPH), and phenylpropanolamine (PPA) from falsely producing positive immunoassay screening results. The study also sought to characterize the prevalence and concentration distributions of EPH, PSEPH, and PPA in samples that produced positive amphetamine screening results. Approximately 27,400 randomly collected human urine samples from Navy and Marine Corps members were simultaneously screened for amphetamines using the DRI and Abuscreen online immunoassays at a cutoff concentration of 500 ng/mL. All samples that screened positive were confirmed for amphetamine (AMP), methamphetamine (MTH), 3,4-Methylenedioxyamphetamine (MDA), 3,4-Methylenedioxymethamphetamine (MDMA), EPH, PSEPH, and PPA by gas chromatography/mass spectrometry (GC/MS). The DRI AMP immunoassay identified 1,104 presumptive amphetamine positive samples, of which only 1.99% confirmed positive for the presence of AMP, MTH, MDA, or MDMA. In contrast, the online AMP reagent identified 317 presumptive amphetamine positives with a confirmation rate for AMP, MTH, MDA, or MDMA of 7.94%. The presence of EPH, PSEPH, or PPA was confirmed in 833 of the 1,104 samples that failed to confirm positive for AMP, MTH, MDA, or MDMA; all of the 833 samples contained PSEPH. When compared to the entire screened sample set, PSEPH was present in approximately 3%, EPH in 0.9%, and PPA in 0.8% of the samples. The results indicate that cross reactivities for EPH, PSEPH, and PPA are greater than reported by the manufacturer of these reagents. The distribution of concentrations indicates that very large concentrations of EPH, PSEPH, and PPA are common. 相似文献
197.
Padosch SA Schmidt PH Schyma C Hirsch RD Kröner LU Dettmeyer RB Madea B 《Archiv für Kriminologie》2004,214(5-6):149-162
The second part of the paper on suicides by gunshots to the head in the presence of witnesses focuses on relevant morphological autopsy findings such as entrance site, signs of close range or contact shots, bullet path etc. and also discusses selected aspects of ascertaining gunshot residues. For the identification of the shooter an integral medicolegal assessment of all the facts including the investigation results and the autopsy findings is essential. However, the morphological findings alone do not allow safe diagnosis, as for example in a homicide the temporal region, which was affected in all our cases, may have been deliberately chosen by the perpetrator as a localization typical of suicide. Thus methods to ascertain gunshot residues on the firing hand (by means of adhesive films and the polyvinyl-alcohol collection method--PVAL) are of great practical importance. In seven cases adhesive films and/or the polyvinyl-alcohol collection method were used. In one case the gunshot residues (GSR) were analysed by means of tape lifts and subsequent scanning electron microscopy (SEM). It was found that especially the combined application of topographical (adhesive tape/PVAL) and cumulative (SEM) methods allowed for the doubtless identification of the shooter, thus usually confirming the suicide. By the example of one case it is demonstrated that without the immediate collection of evidence at the scene objective reconstruction of the event becomes impossible. On the basis of the reported cases recommendations are finally given for a differentiated approach in the medicolegal evaluation of alleged witnessed suicide by gunshot (to the head). 相似文献
198.
199.
In this paper, we describe the development of a device for fuming fingerprints with cyanoacrylate (Super Glue) to enable police tactical units to obtain fingerprint evidence from suspicious packages using a remote-controlled robot. Through a series of initial experiments and preliminary designs, we show that effective cyanoacylate fuming requires sufficient heat, humidity, and airflow. This work led to the development of a final working prototype, called robot accessory for fuming fingerprint evidence (RAFFE), which is currently being field tested by the Calgary Police Service. 相似文献
200.
An HPLC-APCI-MS(/MS) method for the (trace) analysis of the most commonly encountered peroxide explosives, hexamethylenetriperoxidediamine (HMTD) and triacetonetriperoxide (TATP), has been developed. With this method, HMTD and TATP have been analyzed in the same run. (Pseudo-)molecular ions of these peroxides have been obtained as base peak under the same condition. A series of product ions was produced from these pseudo-molecular ions ([HMTD - 1]+ and [TATP + NH4]+) in the MS/MS analysis. We also pioneered in showing that a TATP molecular ion [TATP + H]+ can be observed with HPLC-MS/MS. The limit of detection for HMTD and TATP was 0.26 and 3.3 ng, respectively, on column by HPLC-MS in the Full Scan mode and 0.08 and 0.8, respectively, by HPLC-APCI-MS/MS in Selected Reaction Monitoring (single mass unit) mode. The method presented has been applied successfully for the identification of peroxides in the bulk solid state (powder sample), as well as in post-blast extracts originating from a forensic case. For the post-blast extracts, the use of tandem MS has been shown clearly to be of crucial importance for the identification and detection of the peroxide explosives. 相似文献