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121.
Predictors of engagement in mothers receiving home visitation in the first year of service was examined. Early engagement was studied in three ways: (1) length of time active in the program during the first year of service (duration), (2) number of visits received (quantity), and (3) gaps in service between visits (consistency). Examined visits received in 515 first-time mothers in a Healthy Families America (HFA) program. Parameters of engagement were investigated, and predictors of engagement were identified using demographics and the Kempe Family Stress Inventory. Inclusive of the Assessment Visit, 31.8% of mothers disengaged prior to the first month of service. Remaining active in the program was associated with being Caucasian, and increased parenting risk (mental health/substance abuse history, low social support, increased stress). Most mothers had fewer home visits than prescribed. Gaps in prescribed service were common, with 89.4% of mothers experiencing gaps between visits of 1 month, and dropping to 16.4% having gaps of 2 months. In contrast to findings from clinic-based interventions, early engagement in home visitation is associated with lower levels of functioning and acute needs. These findings add to a growing body of literature suggesting that increased adversity promotes engagement in prevention programs in general, and home visitation programs in particular. To the extent that mothers who are actively engaged in home visitation are likely to have increased psychosocial needs, curricula may require modification and augmentation to address these needs and optimize program effectiveness.  相似文献   
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The Scent Transfer Unit (STU-100) is a portable vacuum that uses airflow through a sterile gauze pad to capture a volatiles profile over evidentiary items for subsequent canine presentation to assist law enforcement personnel. This device was evaluated to determine its ability to trap and release organic compounds at ambient temperature under controlled laboratory conditions. Gas chromatography-mass spectrometry (GC-MS) analyses using a five-component volatiles mixture in methanol injected directly into a capture pad indicated that compound release could be detected initially and 3 days after the time of collection. Additionally, 15 compounds of a 39-component toxic organic gaseous mixture (10-1000 parts per billion by volume [p.p.b.(v)]) were trapped, released, and detected in the headspace of a volatiles capture pad after being exposed to this mixture using the STU-100 with analysis via GC-MS. Component release efficiencies at ambient temperature varied with the analyte; however, typical values of c. 10% were obtained. Desorption at elevated temperatures of reported human odor/scent chemicals and colognes trapped by the STU-100 pads was measured and indicated that the STU-100 has a significant trapping efficiency at ambient temperature. Multivariate statistical analysis of subsequent mass spectral patterns was also performed.  相似文献   
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Initial reports of domestic violence are generally made to law enforcement officers who must respond and intervene. A subset of these episodes involves cases in which the victim, and, in many instances her child(ren), have been taken hostage by her husband or partner. Moreover, there are indications that the number of such incidents is growing. The purpose of this project was twofold: (1) to provide one of the first reports on the prevalence and characteristics of these events, and (2) to more closely analyze domestic crisis (hostage) situations using actual case examples. All information was obtained from the Hostage Barricade Database System (HOBAS) of the FBIs Crisis Negotiation Unit. HOBAS is a postincident information collection tool which stores historical data from law enforcement agencies across the nation on hostage/barricade incidents. An examination of this database yielded different types of domestic hostage-taking acts and outcomes (e.g., tactical vs. negotiated resolutions, survival vs. death/injury of perpetrator and/or victim[s]). Implications of the findings, for future crisis negotiation efforts directed toward nonviolent resolution of these high-risk critical incidents, are discussed.  相似文献   
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This article based, on 38 in-depth interviews with Rotterdam cocaine retail dealers, aims to present a clearer picture of how cocaine supply lines in the Netherlands are organized in order to fine-tune policy with respect to crime, public order and safety on the different trade levels. On the retail level the market for cocaine is strictly separated in a market for crack cocaine versus a market for powder cocaine. The crack dealers are often hard drug users themselves living in relatively poor circumstances. Although dealing cocaine is their main activity, they tend to be involved in other activities related to the drug scene, e.g. smuggling cocaine via Amsterdam airport. The cocaine distribution line for supply on the local market is seldom more than two steps. Because the supply for the Rotterdam cocaine retailers comes mainly from small-scale imports, successful police operations against large-scale imports of cocaine will have little influence on the local cocaine supply in the Netherlands.  相似文献   
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Improved detection of forensic evidence by combining narrow band photographic images taken at a range of wavelengths is dependent on the substance of interest having a significantly different spectrum from the underlying substrate. While some natural substances such as blood have distinctive spectral features which are readily distinguished from common colorants, this is not true for visualization agents commonly used in forensic science. We now show that it is possible to select reagents with narrow spectral features that lead to increased visibility using digital cameras and computer image enhancement programs even if their coloration is much less intense to the unaided eye than traditional reagents. The concept is illustrated by visualising latent fingermarks on paper with the zinc complex of Ruhemann's Purple, cyanoacrylate-fumed fingerprints with Eu(tta)(3)(phen), and soil prints with 2,6-bis(benzimidazol-2-yl)-4-[4'-(dimethylamino)phenyl]pyridine [BBIDMAPP]. In each case background correction is performed at one or two wavelengths bracketing the narrow absorption or emission band of these compounds. However, compounds with sharp spectral features would also lead to improved detection using more advanced algorithms such as principal component analysis.  相似文献   
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