An Optimized Centrifugal Method for Separation of Semen from Superabsorbent Polymers for Forensic Analysis

Connection of a perpetrator to a sexual assault is best performed through the confirmed presence of semen, thereby proving sexual contact. Evidentiary items can include sanitary napkins or diapers containing superabsorbent polymers (SAPs), complicating spermatozoa visualization and DNA analysis. In this report, we evaluated the impact of SAPS on the current forensic DNA workflow, developing an efficient centrifugal protocol for separating spermatozoa from SAP material. The optimized filtration method was compared to common practices of excising the top layer only, resulting in significantly higher sperm yields when a core sample of the substrate was taken. Direct isolation of the SAP‐containing materials without filtering resulted in 20% sample failure; additionally, SAP material was observed in the final eluted DNA samples, causing physical interference. Thus, use of the described centrifugal‐filtering method is a simple preliminary step that improves spermatozoa visualization and enables more consistent DNA yields, while also avoiding SAP interference.     

Unusual sources of Sn in GSR. An experimental study by SEM and IBA

Gunshot Residue (GSR) produced by the discharge of a firearm often provides very useful information in criminal investigations in cases involving the use of firearms. Scanning Electron Microscopy equipped with an Energy Dispersive X-ray Spectrometer (SEM-EDS) is typically used worldwide to visualize micrometric particles constituting GSR and to analyse their elemental composition. The 2017 ASTM Standard guide for gunshot residue analysis by scanning electron microscopy/energy dispersive X-ray spectroscopy specifies that “Particles classified as characteristic of GSR will have one of the following elemental compositions: Lead, antimony, barium; Lead, barium, calcium, silicon, tin”. For the first time, the presence of an additional element, such as Sn, plays a key role in ASTM particle classification. It is known that some ammunitions, used for pistols, revolvers and rifles, contain tin foil discs for sealing the primer mixture into the cup, resulting in GSR particles containing Sn. The authors faced some cases in which Sn was unexpectedly found in GSR particles from a 0.22 Long Rifle derringer and from some 12 gauge shotguns. No tin foil discs are used in rimfire ammunitions and there is no published evidence of tin foil discs in shotshell ammunitions. Following a “case by case” approach, experimental research has been carried out to explain how Sn can be present in GSR particles when the last discharged cartridge also does not contain any Sn either in components and in the explosive charges.Moreover, the use of Particle Induced X-ray Emission (PIXE) showed the capability to overcome overlap ambiguity of Sb and Sn peaks in the X-ray spectra, being a possible key issue in real shooting cases if Sn quantities are below the lower limit of SEM detection, especially when Sb is also present.     

Market forces and private sector processes in government policy: The job training partnership act

This article examines those provisions of the Job Training Partnership Act designed to introduce the presumed efficiency of marketlike forces and incentives into federal employment and training programs. First, the JTPA replaced the administrative system used in earlier training programs (which emphasized detailed federal control and monitoring of the programs at the local level) with a system that, in effect, set a price for a prescribed level of performance and reduced oversight of the training process. Second, the Act gave people in private business some control over programs at the local level. According to available data, JTPA program performance is no different in local areas with a strong private-sector involvement than in areas where that involvement is weak and passive. The performance standards have had an effect, although the relationship between the standards and the goals of the JTPA is ambiguous at best. The article outlines the limitations of a market-oriented system for the administration of public policy.     

The demand revealing process: To distribute the surplus

Contrary to established, frequently repeated proposition that its budget surplus cannot be distributed to taxpayers without disturbing the incentive compatibility of the demand revealing process (DRP), the surplus can be distributed by reapplying the key concept of the DRP. There will remain an aggregate refund error that in a Bayesian sense is random with zero mean, and which vanishes O(1/N)² as the economy becomes large through replication. To dela with income effects. when one does not restrict the domain of the mechanism to separable utility functions, I suggest a variation of the DRP that preserves its incentive compatibility wgeb N is finite.     

Which way to the barricades?

Ann Curthoys, For and Against Feminism. A Personal Journey into Feminist Theory and History (Allen & Unwin) Sydney, 1988; Elizabeth Wilson, Hidden Agendas. Theory, Politics, and Experience in the Women's Movement (Tavistock) London & New York, 1986; Charlotte Bunch, Passionate Politics. Feminist Theory in Action (St. Martin's Press) New York, 1987.     

Signals from the Tenth Justice: The Political Role of the Solicitor General in Supreme Court Decision Making

Conventional explanations of the solicitor general's influence on the Supreme Court emphasize his expertise or experience. We articulate and test a more political account based on insights from signaling theory. We argue justices will be more receptive to signals from the solicitor general (S.G.) when either the justice and S.G. are ideologically proximate or the S.G.'s signal is contrary to his ideological predisposition. We test our account over the period from 1953 to 2002 using a newly developed interinstitutional measure of ideology that places executive and judicial actors on the same spatial scale. Our results highlight the political nature of the S.G.'s influence, challenging the received wisdom about the S.G.'s impact on the Supreme Court.