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371.
372.
Abstract: Samples containing the toxic castor bean protein ricin have been recently seized in connection with biocriminal activity. Analytical methods that enable investigators to determine how the samples were prepared and to match seized samples to potential source materials are needed. One commonly described crude ricin preparation method is acetone extraction of crushed castor beans. Here, we describe the use of solid‐phase microextraction and headspace analysis to determine whether castor beans were processed by acetone extraction. We prepared acetone‐extracted castor bean mash, along with controls of unextracted mash and mash extracted with nonacetone organic solvents. Samples of acetone‐extracted mash and unextracted mash were stored in closed containers for up to 109 days at both room temperature and ?20°C, and in open containers at room temperature for up to 94 days. Acetone‐extracted bean mash could consistently be statistically distinguished from controls, even after storage in open containers for 94 days.  相似文献   
373.
Abstract: The Food and Drug Administration does not require surgical sutures to be tracked by manufacturer, physician, or patient; thereby, surgical sutures have been of little use to forensic practitioners who are tasked with establishing a positive identification with biological evidence. This study demonstrates the investigative process used to pinpoint suture manufacturers by presenting a case where surgical sutures were a distinctive characteristic that aided in the positive identification of skeletal remains. The suture’s manufacturer, construction material and structure, size, and medical use was determined by contacting a local surgical suture and orthopedic implant manufacturer and utilizing publicly available manufacturer websites, which provide catalogs and specific product details. This research was one of many lines of evidence used to establish the positive identification of a 47‐year‐old male.  相似文献   
374.

Abstract:

An alarming number of drownings occur in lifeguarded swimming areas, where one might presume swimmers are protected from injury. One reason drownings occur in lifeguarded swimming areas is because lifeguard surveillance is a highly difficult task. Observational research suggests lifeguards are usually alert, but researchers also report egregious examples of inattention. We offer three strategies that have initial empirical support to reduce risk of drowning at lifeguarded swimming areas: (a) regular training to help lifeguards recognize they are vulnerable to drowning events and to raise their confidence; (b) regular practice via simulated emergency responses, and (c) addressing staff schedules so lifeguards can devote full attention to protecting swimmer safety while on duty. ‎  相似文献   
375.
Polydimethylsiloxane (PDMS) is commonly used to lubricate condoms. The detection of PDMS on swabs from complainants can be used to support an allegation of sexual assault. Previous research has focused on establishing analytical techniques for detecting PDMS. This research examined the persistence of PDMS on the penis, in the vagina, in the mouth, and on skin. The longest PDMS detection times were 20 h on the penis, 35 h in the vagina, and 52 h on skin. PDMS was detected up to 4 h in the mouth if the participant did not eat or drink and up to 9 h if the participant slept. PDMS was not detected in the mouth after eating or drinking. The presence of biological fluids had no detrimental effect on the analysis. Aqueous extraction of swabs for DNA did not remove any significant amount of PDMS; hence, swab remains could be subsequently analyzed for PDMS.  相似文献   
376.
State and local governments are designing programs to prevent child maltreatment at an increasing rate. A relatively small portion of families offered these programs go on to engage in and complete services. Workers in a child maltreatment prevention program implemented across 21 sites in 1 state documented outreach efforts in logs maintained by program evaluators. Additionally, evaluators interviewed 23 outreach workers and supervisors who were developing and refining outreach strategies in this prevention program. Data from logs and responses to interviews speak to challenges in navigating prevention outreach with families to achieve engagement and buy-in, particularly when “cold-calling” about screened-out reports of child maltreatment. This paper presents a summary of barriers and facilitators of family engagement in outreach for prevention services, guidance from the public health literature on improving outreach strategies for at-risk populations, and suggested practice, policy, and research implications.  相似文献   
377.
Perceptions of children's credibility were studied in two experiments wherein participants watched a videotape of a 4- to 5- or a 6- to 7-year old child report details of a play session that had been experienced once (single-event) or was the last in a series of four similar play sessions (repeat-event). The child's report was classified as high or low accurate. In Experiments 1 and 2, reports of repeat-event children were judged to be less believable on several measures. In Experiment 1, younger children were viewed as less credible than older children. In both experiments, neither undergraduates nor community members correctly discriminated between high- and low-accurate reports. Content analysis in Study 3 revealed the relationship between age and event frequency and children's credibility ratings was mediated by the internal consistency of children's reports. Recent research on children's reports of instances of repeated events has identified several challenges facing children who report repeated abuse. These data bring to light another potential difficulty for these children.  相似文献   
378.
On 13 December 2000, British Telecom (BT) filed what must be one of the more unlikely patent infringement actions to have come before the courts recently. As a result of a routine review of its global patent portfolio, BT made the somewhat serendipitous discovery that it owns an old US patent which, according to BT, covers the concept of hyperlinking. The patent was granted in 1989 and is due to run until 2006. Similar patents were filed around the world, but have all now expired. This article explores the passage of the dispute in the US courts and explains how BT’s case came to flounder at the first hurdle.  相似文献   
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380.
As a first step in developing a molecular method for the individualization of marijuana samples, we evaluated a plant DNA extraction kit. The QIAGEN plant DNeasy method uses a spin column format for recovery of DNA and is effective for obtaining high molecular weight DNA from leaf, flower (bud), and seed samples of marijuana. The average DNA yield was 125-500 ng per 100 milligrams of fresh plant tissue. The recovered DNA was of polymerase chain reaction (PCR) quality as measured by the ability to generate reproducible amplified fragment length polymorphism (AFLP) profiles. AFLP is a technique used to create a DNA profile for plant varieties and is being applied to marijuana samples by the authors to link growers and distributors of clonal material. The QIAGEN plant DNeasy method was simple, efficient, and reproducible for processing small quantities of marijuana into DNA.  相似文献   
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