Image analysis of gunshot residue on entry wounds. II--A statistical estimation of firing range.

A statistical investigation of the relationship between firing range and the amount and distribution of gunshot residue (GSR), used automated image analysis (IA) to quantify GSR deposit resulting from firings into pig skin, from distances ranging between contact and 45 cm. Overall, for a Ruger .22 semi-automatic rifle using CCI solid point, high velocity ammunition, the total area of GSR deposit on the skin sections decreased in a non-linear fashion with firing range. More specifically there were significant differences in the amount of GSR deposited from shots fired at contact compared with shots fired from distances between 2.5 and 45 cm; and between shots fired from a distance of 20 cm or less, with shots fired at a distance of 30 cm or more. In addition, GSR particles were heavily concentrated in the wound tract only for contact and close range shots at 2.5 cm, while the particle distribution was more uniform between the wound tract and the skin surfaces for shots fired from distances greater than 2.5 cm. Consequently, for future scientific investigations of gunshot fatalities, once standards have been established for the weapon and ammunition type in question, image analysis quantification of GSR deposited in and around the gunshot wound may be capable of providing a reliable, statistical basis for estimating firing range.     

Hypoxic/ischaemic brain damage, especially pallidal lesions, in heroin addicts.

The occurrence of pallidal lesions with or without other hypoxic/ischaemic brain injuries was evaluated in 100 intravenous (i.v.) heroin addicts. The brains were collected consecutively from forensic autopsies during the period from January 1995 to June 1996. The autopsies were required by the police and performed at The Institute of Forensic Medicine, The National Hospital, Oslo. There were 21 women and 79 men, median age 32 (range 21-47) and 34 (19-60) years, respectively. Of 38 brains with abnormalities, twenty-five cases showed isolated or combined lesions of hypoxic/ischaemic origin. Pallidal lesions were found in nine brains; six lesions were old, one was subacute (a couple of weeks), and two were part of recent, generalized hypoxia/ischaemia. Six persons had old infarcts in the hippocampal formation, and one of them in combination with old pallidal infarcts. In seven brains small and old infarcts were found in watershed areas in the cerebellum. Between five and ten percent of i.v. heroin addicts might have pallidal infarcts, either as the sole lesion, or combined with other manifestations of hypoxic/ischaemic brain injury. This might give severe mental disturbances in the affected persons.     

Industry, occupation, and disability insurance beneficiary work return.

This article uses the New Beneficiary Data System to describe the first job held after award of Disability Insurance benefits, in terms of occupation and industry. It examines work activity within sectors of employment, and looks at the issues of whether work return in certain industries and occupations varies according to the demographic characteristics of the beneficiaries. The article also presents data on sector-specific employer accommodations that can aid in sustained work return. Postentitlement work was fairly evenly distributed across occupational and industrial sectors. Persons with higher levels of educational attainment were found to be in white-collar employment sectors. There were noticeable differences in the availability of employer accommodations across postentitlement occupations and industries.     

Specificity versus representativeness: methodological approaches to the study of Mexico-U.S. migration

"This article compares two sources of data on Mexico-U.S. migration, based on radically different methodologies: the Mexican Migration Project (Promig) and the National Survey of Population Dynamics (Enadid).... This comparative study shows that a micro-social design drawing on multiple community samples, such as Promig, can solve the methodological conflict between specificity and representativeness.... The authors' research also highlights the problem of selectivity and specificity entailed by traditional surveys such as Enadid as a result of restricting their samples to international residents in Mexico and attempting to explain such a complex, socioeconomic process using a limited number of variables." (EXCERPT)     

Why do people vote? An experiment in rationality

The study presents the findings of an experiment conducted during the 1993 Canadian fedeal election campaign. Students in two universities were exposed to a ten-minute presentation about the rational model of voting and the ‘paradox’ that so many people vote when it is apparently irrational on a cost-benefit basis. Our data indicate that exposure to the presentation decreased turnout in the election by seven percentage points. This result contributes to the debate abut the effect of rational-choice models on real political behavior. More important, the experimental panel data permit the presentation's effect to be decomposed, and this helps explain why people do vote. In this study, turnout was reduced mainly because the presentation diminished the respondents' sense of duty, an effect that was indirect, because there was no reference in the presentation to such motives. Framing the voting act in rational-choice terms induced some students to reconsider whether they should feel obliged to vote.