Blast Suppression Foam,Aqueous Gel Blocks,and their Effect on Subsequent Analysis of Forensic Evidence*

In addition to having blast mitigation properties, aqueous foam concentrate AFC-380 blast suppression foam is designed to capture aerosolized chemical, biological, and radioactive particles during render-safe procedures of explosive devices. Exposure to aqueous environments and surfactants may negatively affect forensic evidence found at the scene, but the effects of AFC-380 foam and aqueous gel on the preservation and subsequent analysis of forensic evidence have not previously been investigated. Sebaceous finger and palm prints and DNA samples on paper, cardboard, tape, and various metal and plastic items, along with hairs, carpet and yarn fibers, and inks and documents, were exposed to AFC-380 foam. Similar mock evidence was also exposed to a superabsorbent gel of the type found in aqueous gel blocks used for shrapnel containment. Exposure to foam or aqueous gel was associated with a dilution effect for recovered DNA samples, but quality of the samples was not substantially affected. In contrast, exposure to AFC-380 foam or gel was detrimental to development of latent finger and palm prints on any substrate. Neither the hair nor the fiber samples were affected by exposure to either the foam or gel. Indented writing on the document samples was detrimentally affected by foam or gel exposure, but not inks and toners. The results from this study indicate that most types of forensic evidence recovered after being exposed to aqueous gel or blast suppression foam can be reliably analyzed, but latent finger and palm prints may be adversely affected.     

When Do Low Roll Rates Indicate Party Influence? Evidence from Counterfactual Roll Rates

A simulation-based counterfactual is one way to solve the observational equivalence challenge that seemingly “partisan” majority-party roll rates can be observed in the absence of any actual party influence. We simulate no-partisan-agenda-control counterfactual roll rates and apply them across sessions of the US House of Representatives and 86 state legislative chambers to evaluate the extent to which observed roll rates provide evidence for party influence on the legislative agenda. After assessing and controlling for the baseline risk of majority-party rolls, there is significant evidence of party influence on roll rates in some state legislatures, particularly those with rules that grant parties more agenda power, and in the post-Reed’s-rules House of Representatives. Institutional rules interact with the (simulated) risk of a majority roll to shape observed roll rates across chambers and across time.     

Experts and evidence in deliberation: scrutinising the role of witnesses and evidence in mini-publics,a case study

Policy Sciences - Experts hold a prominent position in guiding and shaping policy-making; however, the nature of expert input to decision-making is a topic of public debate. A key aspect of...     

Do Animals Have an Interest in Liberty?

Proponents of justice for animals often argue that non-human animals have an interest in liberty. Furthermore, they usually claim that this animal interest in liberty is intrinsic rather than instrumental; that is to say, liberty is regarded to be good for animals in itself, irrespective of its contribution to the achievement of other goods, such as pleasure. For this reason they argue that legislating to improve welfare standards in zoos, circuses, laboratories and agriculture is inadequate. Instead, they claim that such practices are analogous to human slavery, necessarily harmful and must be abolished. In this article I refute this assertion and claim that for most animals, their interest in liberty can only ever be instrumental. In doing so I outline and reject two different arguments in favour of an intrinsic animal interest in liberty: first, that liberty is an intrinsic interest of animals because they possess preference autonomy; and second, that it is good for animals to be free, where freedom is defined as the ability to exercise one's natural functionings. I conclude that most animals do not possess an intrinsic interest in liberty because they are not autonomous in the relevant sense; that is, they cannot frame, revise and pursue their own conception of the good. If my conclusion is correct, this would have important effects on our obligations to non-human animals. I end the article by introducing some of these possible implications. Specifically, I propose that for most animals, our obligations do not consist of liberating them, and that it might be permissible to use and interfere with animals more often than other proponents of justice for animals have suggested. If this is the case, not all of the ways we keep and use animals need to be abolished. Nevertheless, many need to be reformed to improve welfare standards.     

Making Short Politics Placements Work

Short placements can provide an important and meaningful experience of politics in action for students who are unable to benefit from the generally lengthy placements currently on offer. This article is based on the findings of the three-year HEFCE-funded project The Scholarship of Engagement for Politics and explores the potential of short, local, research-based placements, which are embedded in modules, supported by online journaling and effectively assessed, to enrich students' understanding of politics and enhance their employability.     

Effect of Victimization on Impulse Control and Binge Drinking among Serious Juvenile Offenders from Adolescence to Young Adulthood

A vast literature has found longitudinal effects of early life stress on substance use and self-regulatory processes. These associations may vary by period-specific development among youth involved in the juvenile justice system. The current study used an accelerated longitudinal design and auto-regressive latent trajectory with structure residuals (ALT-SR) model to examine the within-person cross-lagged associations between binge drinking, impulse control, and victimization from 15 to 25 years of age. A large sample (N?=?1100) of justice-involved youth were followed longitudinally for 7 years (M _{age baseline} ?=?15.8, M _{age conclusion} ?=?22.8). In general, the sample was ethnically diverse (41% Black, 34% Hispanic, 21% White, 4.3% Other) and primarily male (87.2%). Participants reported on their frequency of binge drinking, impulse control, and frequency of victimization at each time point. The results indicated that, during adolescence, victimization and binge drinking attenuated impulse control, which resulted in more binge drinking and victimization during young adulthood. The current study highlights the importance of assessing developmental processes and period-specific transitions among at risk youth, especially for youth experiencing early life stress.     

A Community-Level Comparison of Terrorism Movements in the United States

The aim of this article is to identify characteristics of communities where persons indicted under terrorism charges lived, planned, and prepared prior to carrying out a terrorist act. Guided by a model of community deterioration and using data from the Terrorism and Extremist Violence in the United States database, findings indicate: (1) half of all census tracts where terrorists planned and prepared for attacks were located in the western United States; nearly one fourth were in the Northeast; (2) nationally, terrorist pre-incident activity is more likely to occur in census tracts with lower percentages of high school graduates for Al Qaeda and associated movements (AQAM) terrorism but not for far-right terrorism, higher percentages of households living below the poverty level, more urban places, and more unemployed; and (3) communities with terrorist pre-incident activity are different types of places compared to those where there was no pre-incident activity, generally between different regions of the country, and specifically in terms of differences across far-right and AQAM terrorist movements.     

Computer‐Assisted Keyword and Document Set Discovery from Unstructured Text

The (unheralded) first step in many applications of automated text analysis involves selecting keywords to choose documents from a large text corpus for further study. Although all substantive results depend on this choice, researchers usually pick keywords in ad hoc ways that are far from optimal and usually biased. Most seem to think that keyword selection is easy, since they do Google searches every day, but we demonstrate that humans perform exceedingly poorly at this basic task. We offer a better approach, one that also can help with following conversations where participants rapidly innovate language to evade authorities, seek political advantage, or express creativity; generic web searching; eDiscovery; look‐alike modeling; industry and intelligence analysis; and sentiment and topic analysis. We develop a computer‐assisted (as opposed to fully automated or human‐only) statistical approach that suggests keywords from available text without needing structured data as inputs. This framing poses the statistical problem in a new way, which leads to a widely applicable algorithm. Our specific approach is based on training classifiers, extracting information from (rather than correcting) their mistakes, and summarizing results with easy‐to‐understand Boolean search strings. We illustrate how the technique works with analyses of English texts about the Boston Marathon bombings, Chinese social media posts designed to evade censorship, and others.