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21.
The objective was to investigate color change and surface damage in dental resin composites exposed to high temperatures over different time intervals for comparative purposes. Samples were prepared using two resins - Z100(R) (R1) and Charisma (R2), heated at the following temperatures: 200 degrees C, 400 degrees C, 600 degrees C, 1000 degrees C, for 15, 30 and 45 min (n = 104 for each resin sample). Color (DeltaE) and brightness (DeltaL) changes were analyzed by spectrophotometry using the CIE Lab system and surface changes by Scanning Electron Microscopy (SEM). R1 showed more intense color changes after heat exposure than R2. DeltaL values were found to be the best parameter for evaluation of light and color change. A biphasic pattern after thermal exposure was detected, from dark brown to light white. SEM showed more intense alterations in R2 than in R1. These results indicate that the parameters observed in both resins are useful as a guide in forensic analyses.  相似文献   
22.
In Morgentaler v. R., the Supreme Court of Canada struck down the abortion provisions in the Criminal Code. In a five to two split, a majority of the Supreme Court judges found that section 251 offended a pregnant woman's constitutionally protected right not to be deprived of her "life, liberty, and security of the person." Sheilah Martin reviews the three majority judgments and focuses on the decision written by Madame Justice Wilson. She believes that Madame Justice Wilson's opinion merits special attention in several regards: her conclusions on the constitutional rights of pregnant women; her recognition and validation of women's perspectives on abortion; and her approach to balancing women's interests in reproductive self-determination against the state's interest in regulating reproduction. Sheilah Martin concludes that this decision will reverberate far into the future. Even though it fails to establish clear guidelines concerning governmental power to control access to abortion, its principles outline the legal framework in which future litigation will occur, and it will limit and shape the terms of any ensuing political debate. In addition, Madame Justice Wilson's judgment holds great promise for those looking to the Court to promote the rights of women and other historically disadvantaged groups.  相似文献   
23.
With few exceptions, prior explanations of racially disparate punishment have followed a dichotomous approach (i.e., African American versus Caucasian), due in part to the limitations of existing data. Researchers have either excluded Latino/a, defendants or treated them as a monolithic group. Consequently, there is not much on Latinos/as, whose experiences with the criminal and juvenile justice systems differ from those of African American and Caucasian. This article expands on current literature by providing a thorough overview of existing literature on Latino/as. It critiques this body of literature and lists ten common methodological flaws that may contribute to findings of equal treatment. Finally, it provides a concise summary of the main subgroups within the umbrella term ‘Latino/a’ to highlight the heterogeneity within this classification.  相似文献   
24.
This research examines whether women who have experienced intimate partner violence (IPV) during pregnancy have a higher child abuse potential than women who have not experienced IPV. Data were analyzed from a longitudinal investigation of IPV during pregnancy. This study recruited 88 pregnant women during prenatal care and followed them for 1(1/2) years. IPV was assessed using the Conflict Tactics Scale 2 (CTS2). The woman's potential for child abuse was assessed using the Child Abuse Potential Inventory (CAPI). There was a significant positive association between IPV and child abuse potential scores (p = .003), even after controlling for sociodemographics. The odds of having a high level of child abuse potential were 3 times greater for women who were victims of IPV compared to nonvictims. Higher child abuse potential scores of the victimized women resulted mainly from the Distress and Problems with Others CAPI scales.  相似文献   
25.
Abstract: Forensic laboratories around the world have seen an increase in the number of drug seizures containing methorphan. Levomethorphan is a narcotic and a controlled substance, and its enantiomer dextromethorphan is an antitussive agent used in over‐the‐counter medications. For the forensic analysis of seized drugs containing methorphan, it is important to report the stereochemical composition of the drug. Ideally, a method based on common forensic laboratory instrumentation is desirable. The use of the chiral derivatizing agent (?)‐menthyl chloroformate followed by routine gas chromatography–mass spectrometry analysis of the derivative was shown to successfully determine the stereochemical composition of methorphan. This approach was applied to a street seizure containing methorphan proving that it was pure dextromethorphan. The derivatives of dextro‐ and levomethorphan were subjected to mass spectroscopic and nuclear magnetic resonance analysis, which confirmed that the structure of the derivatives remained unchanged as a result of the derivatization process.  相似文献   
26.
A procedure has been developed to analyze the trace element concentrations in glass fragments using particle-induced X-ray emission (PIXE) spectrometry. This method involves using accelerated protons to excite inner-shell electronic transitions of target atoms and recording the resultant X-rays to characterize the trace element concentrations. The protocol was able to identify those glass fragments that originated from different sources based on their elemental analyses. The protocol includes specific approaches to calculating uncertainties and handling measurements below the level of detection. The results indicate that this approach has increased sensitivity for several elements with higher atomic number compared with X-ray fluorescence methods. While not as sensitive as laser-ablation or inductively coupled plasma mass spectrometry methods of dissolved samples, it is entirely nondestructive and entails a much simpler sample preparation process that may be used to presort glass fragments for more comprehensive elemental analysis. As such, the technique described may have a niche role in forensic glass analysis.  相似文献   
27.
We investigated agency directors' perspectives about how service goals should be prioritized for domestic violence and sexual assault service subtypes, including crisis, legal advocacy, medical advocacy, counseling, support group, and shelter services. A sample of 97 (94% response rate) North Carolina domestic violence and/or sexual assault agency directors completed a survey asking participants to rank the importance of service goals. Overall, participants considered emotional support provision to be a critical service goal priority across all service types. Social support and self-care service strategies were deemed less important. However, prioritization of other service goals varied depending on the service type. Statistically significant differences on service goal prioritization based on key agency characteristics were also examined, and agency characteristics were found to relate to differences in service goal prioritization.  相似文献   
28.
29.
Abstract: In this article, the authors discuss the problem of forensic authentication of digital audio recordings. Although forensic audio has been addressed in several articles, the existing approaches are focused on analog magnetic recordings, which are less prevalent because of the large amount of digital recorders available on the market (optical, solid state, hard disks, etc.). An approach based on digital signal processing that consists of spread spectrum techniques for speech watermarking is presented. This approach presents the advantage that the authentication is based on the signal itself rather than the recording format. Thus, it is valid for usual recording devices in police‐controlled telephone intercepts. In addition, our proposal allows for the introduction of relevant information such as the recording date and time and all the relevant data (this is not always possible with classical systems). Our experimental results reveal that the speech watermarking procedure does not interfere in a significant way with the posterior forensic speaker identification.  相似文献   
30.
There is a general acceptance that cellular material will transfer from one person to another person's fingernails through everyday contact. However, the level or degree of contact required to transfer sufficient cellular material in order to obtain a DNA profile is not known. This study examined swabs from the fingernails of 40 volunteers and compared the DNA profiles obtained to the daily activities of that individual. The majority (78%) of high level profiles obtained were associated with recent intimate contact. However, high level profiles were also obtained from the fingernails of individuals who shared accommodation with their partner, flatmates and/or children. Low level profiles and single profiles were associated with all levels of contact.  相似文献   
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