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241.
This study examined the in vitro stability of 6-acetylmorphine (6AM) in horse blood, sheep vitreous humour (VH) and homogenised deer muscle stored under different storage conditions. The stability of 6AM in horse blood is of interest because many toxicological laboratories utilise this matrix for the preparation of blood calibration and check standards and the latter are typically stored during routine use. Data on the storage stability of 6AM in human VH is extremely limited and no data has been reported in muscle. In the absence of human samples, 6AM stability was demonstrated in sheep vitreous and deer muscle. Blood and VH were stored with and without NaF at room temperature (RT), 4 and -18°C for 84 days. Muscle tissue homogenates were prepared in water with and without NaF and also in phosphate buffer (pH 6.0) containing NaF. Homogenates were stored for 31 days at RT, 4 and -18°C. Morphine and 6AM were extracted using SPE and quantified by GC-ion trap-MS/MS. In the absence of NaF, 6AM could not be detected after 7 and 14 days in blood stored at RT and 4°C, respectively. Although at -18°C 6AM was stable for 7 days (12% loss), only 54% was detected by day 84. The addition of NaF to horse blood increased 6AM stability substantially at every temperature. Further, the rate of degradation was found to be significantly slower in blood preserved with 2% NaF compared with 1% NaF (p=.05). 6AM was stable for the study period in preserved blood (1 and 2% NaF) stored at -18°C. For laboratories utilising horse blood in the preparation of standards, preservation with 1% NaF (minimum) and storage at -18°C is recommended. The addition of NaF to VH was essential for 6AM stability. Irrespective of temperature substantial losses (≥ 42%) were observed in unpreserved sheep VH by day 7. In preserved VH the concentration declined by only 22% on day 7 following storage at RT and no loss observed in VH stored at 4 and -18°C at the same time. In muscle, 6AM was stable for 7 days in preserved samples stored at RT and in all samples stored at 4°C and below. The addition of NaF increased the stability of 6AM substantially in muscle. The increased stability of 6AM in VH and muscle preserved with fluoride was attributed to inhibition of bacterial action and the subsequent reduction in the rate of putrefaction of these tissues.  相似文献   
242.
Fourier-transform infrared spectroscopy (FTIR), discriminate analysis, X-ray fluorescence spectrometry (XRF), and stereoscopic microscopy were used to separate black coral forensic evidence items from similarly appearing items manufactured from plastics, bovid keratin, and mangrove wood. In addition, novel observations were made of bromine and iodine relationships in black coral that have not been previously reported.  相似文献   
243.
This paper extends previous research and discussion on the use of multivariate continuous data, which are about to become more prevalent in forensic science. As an illustrative example, attention is drawn here on the area of comparative handwriting examinations. Multivariate continuous data can be obtained in this field by analysing the contour shape of loop characters through Fourier analysis. This methodology, based on existing research in this area, allows one describe in detail the morphology of character contours throughout a set of variables. This paper uses data collected from female and male writers to conduct a comparative analysis of likelihood ratio based evidence assessment procedures in both, evaluative and investigative proceedings. While the use of likelihood ratios in the former situation is now rather well established (typically, in order to discriminate between propositions of authorship of a given individual versus another, unknown individual), focus on the investigative setting still remains rather beyond considerations in practice. This paper seeks to highlight that investigative settings, too, can represent an area of application for which the likelihood ratio can offer a logical support. As an example, the inference of gender of the writer of an incriminated handwritten text is forwarded, analysed and discussed in this paper. The more general viewpoint according to which likelihood ratio analyses can be helpful for investigative proceedings is supported here through various simulations. These offer a characterisation of the robustness of the proposed likelihood ratio methodology.  相似文献   
244.
Although the importance of parental support for child sexual abuse victims is well documented, the nature of parental support for victims sexually abused by adolescents is less understood. In this exploratory study, we examine whether parents differ in their levels of blame or doubt for their child when sexually abused by adolescents versus adults. Data included 161 reports of child sexual abuse. Parental blame toward their child was higher when sexually abused by an adolescent versus an adult suspect. In the bivariate and multivariate analysis, parental blame was significantly higher as victim age increased, for Black, non-Hispanic children, and when there was an adolescent suspect. Practitioners need to recognize that high levels of blame and doubt could exist for adolescent victims of sexual abuse and when children are sexually abused by adolescents.  相似文献   
245.
Advocates, clinicians, policy makers, and survivors frequently cite intimate partner violence (IPV) as an immediate cause of or precursor to housing problems. Research has indicated an association between homelessness and IPV, yet few studies examine IPV and housing instability. Housing instability differs from homelessness, in that someone experiencing housing instability may currently have a place to live but faces difficulties with maintaining the residence. We present baseline findings from a longitudinal cohort study of 278 female IPV survivors with housing as a primary concern. Our analysis indicates the greater the number of housing instability risk factors (e.g., eviction notice, problems with landlord, moving multiple times), the more likely the abused woman reported symptoms consistent with PTSD (p < .001), depression (p < .001), reduced quality of life (p < .001), increased work/school absence (OR = 1.28, p < .004), and increased hospital/emergency department use (OR = 1.22, p < .001). These outcomes persist even when controlling for the level of danger in the abusive relationship and for survivors' drug and alcohol use. Importantly, both housing instability and danger level had stronger associations with negative health outcomes than other factors such as age, alcohol, and drug use; both make unique contributions to negative health outcomes and could contribute in different ways. Housing instability is an important and understudied social determinant of health for IPV survivors. These findings begin to address the literature gap on the relationship between housing instability, IPV, and survivors' health, employment, and utilization of medical care services.  相似文献   
246.
Research suggests that many women experience some form of sexual assault in their lifetime and that women who engage in substance abuse often have a higher incidence of past sexual assault than women in the general population. Given the documented rates of sexual assault among women in recovery from substance use, it is important to explore community interventions that promote positive recovery from substance use and sexual assault. One model that promotes successful substance use recovery is the Oxford House--a democratic, self-supported substance use recovery home. Research demonstrated that living in an Oxford House provides sober social support and that this increased social support may promote the use of positive coping strategies to strengthen recovery from substance use, however; the relationship between social support and sexual assault for women is unclear. Thus, the current study examines the Oxford House model for women in recovery from substance use who have experienced sexual assault. A cross-sectional sample of women living in Oxford Houses in the United States was obtained to examine the relationship among disclosure of sexual assault, social support, and self-esteem. Results suggested that many women used Oxford House as a setting in which to disclosure prior sexual assault. Results also indicated that women who disclosed their assault experience reported higher self-esteem and social support than women who had not disclosed. Possible implications include the value of substance abuse recovery homes as a safe, supportive environment for women to address issues related to sexual assault.  相似文献   
247.
A growing literature suggests that communication strategies can promote or inhibit intimate partner violence (IPV). Research on communication is still needed on a group ripe for early IPV intervention: high school-aged adolescents. This article revisits our previous analyses of young female reproductive clinic patients (Messinger, Davidson, & Rickert, 2011) by examining how the adolescent and young adult respondents differ. To explore replicability of the adolescent results across populations, they are compared to 487 adolescent female students sampled from four urban high schools. Across samples, all communication strategies were used more frequently within violent relationships. Multivariate analysis identified escalating strategies used and received as being positively associated with physical violence used and received in all three samples. Regarding verbal reasoning and temporary conflict avoidance, substantial differences appeared between the young adult and adolescent clinic samples, and results from the adolescent clinic sample were largely replicated with the adolescent school sample, suggesting that young adult samples in this literature are not adequate proxies for adolescents.  相似文献   
248.
Following the September 11, 2001 terrorist attacks, letters containing Bacillus anthracis were distributed through the United States postal system killing five people. A complex forensic investigation commenced to identify the perpetrator of these mailings. A novel liquid chromatography/mass spectrometry protocol for the qualitative detection of trace levels of meglumine and diatrizoate in dried spore preparations of B. anthracis was developed. Meglumine and diatrizoate are components of radiographic imaging products that have been used to purify bacterial spores. Two separate chromatographic assays using multiple mass spectrometric analyses were developed for the detection of meglumine and diatrizoate. The assays achieved limits of detection for meglumine and diatrizoate of 1.00 and 10.0 ng/mL, respectively. Bacillus cereus T strain spores were effectively used as a surrogate for B. anthracis spores during method development and validation. This protocol was successfully applied to limited evidentiary B. anthracis spore material, providing probative information to the investigators.  相似文献   
249.
A collaborative study on Raman spectroscopy and microspectrophotometry (MSP) was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on different dyed cotton fabrics. The detection limits of the two methods were tested on two cotton sets with a dye concentration ranging from 0.5 to 0.005% (w/w). This survey shows that it is possible to detect the presence of dye in fibres with concentrations below that detectable by the traditional methods of light microscopy and microspectrophotometry (MSP). The MSP detection limit for the dyes used in this study was found to be a concentration of 0.5% (w/w). At this concentration, the fibres appear colourless with light microscopy. Raman spectroscopy clearly shows a higher potential to detect concentrations of dyes as low as 0.05% for the yellow dye RY145 and 0.005% for the blue dye RB221. This detection limit was found to depend both on the chemical composition of the dye itself and on the analytical conditions, particularly the laser wavelength. Furthermore, analysis of binary mixtures of dyes showed that while the minor dye was detected at 1.5% (w/w) (30% of the total dye concentration) using microspectrophotometry, it was detected at a level as low as 0.05% (w/w) (10% of the total dye concentration) using Raman spectroscopy. This work also highlights the importance of a flexible Raman instrument equipped with several lasers at different wavelengths for the analysis of dyed fibres. The operator and the set up of the analytical conditions are also of prime importance in order to obtain high quality spectra. Changing the laser wavelength is important to detect different dyes in a mixture.  相似文献   
250.
The current study aimed to examine formal and informal help-seeking responses to interpersonal victimization among a national sample of Latino women. In addition, an examination of help-seeking by victimization type was undertaken. Data came from the Sexual Assault Among Latinas (SALAS) study that obtained help-seeking rates among a victimized subsample of Latino women (n = 714; 35.7% of a national sample). Results show a majority (76.6%) of the victimized participants engaged in some form of help-seeking with informal resources (68.9%) more often used than formal (32.5%). Medical attention was the type of formal help-seeking sought most often among victimized women who were injured (34.7%), and parents were the most common source of informal help-seeking (26.6%). However, logistic regression analyses show that help-seeking responses were significantly affected by type of victimization. Latino women who experienced childhood victimization were significantly less likely to engage in formal and informal help-seeking. Latino women who experienced stalking were significantly less likely to engage in formal help-seeking. Victimization with a weapon was significantly related to increased odds of formal help-seeking. Thus, women respond to violence in a way that is shaped by the dynamics of the victimization experience. Practice implications include the need to increase knowledge and availability of formal help-seeking venues.  相似文献   
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