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931.
L'Abbé EN 《Forensic science international》2005,151(2-3):201-206
In the spring of 2003, bush cutters discovered a large grain bag filled with human skeletal remains in a forest in South Africa. Differential taphonomic processes observed on the bones suggested that the individuals had not died at the same time or had decomposed under different circumstances. The remains were sorted using gross morphological techniques which included assessing the number of skeletal elements present, visual pair matching, articulation, process of elimination and taphonomy. Standard techniques were used to estimate age, sex, racial affinity and stature. A minimum number of individuals (MNI) of 10 was established, which included 7 adult males, 1 adult female and 2 juveniles. Trauma was observed on only one individual. Approximately, 80% of the skeletal remains were missing. These various skeletal elements may have been lost by accident, normal taphonomic processes or taken by scavengers. Possible origins for these skeletal remains include removal from a formal grave, found in the veldt or murdered. 相似文献
932.
The solution parameters associated with gradient elution reversed phase high-performance liquid chromatography (HPLC) were characterized by evaluating the electrospray ionization mass spectrometry (ESIMS) response of selected smokeless powder additives. Using direct liquid infusion, the positive ion ESIMS responses were determined for three general classes of powder constituents: dialkylphthalate acid esters, N,N'-dialkyl-N,N'-diphenyl urea based stabilizers and nitroso-, nitro-, and dinitro- derivatives of diphenylamine. The relative ESIMS intensities of the powder components were investigated as a function of three solution parameters: ammonium acetate concentration, pH, and percent methanol. The effect of the ammonium acetate concentration demonstrates that the electrolyte is required for efficient ionization and the ESIMS intensity was optimal at a concentration of 2mM for the selected compounds, except 2,4'-dinitrodiphenylamine. The aqueous solution pH, corresponding to the available protons in solution, did not have a significant effect on the ESIMS intensity of the analytes. The percent methanol was evaluated with both decreasing and constant electrolyte concentrations to demonstrate the effects of droplet stability and ion transfer into the gas phase. These findings were applied to the analysis of the selected smokeless powder additives using HPLC-ESIMS to illustrate increased sensitivity for the protonated molecules. 相似文献
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934.
Renita?R.?Glaser M.?Lee?Van.?Horn Michael?W.?ArthurEmail author J.?David.?Hawkins Richard?F.?Catalano 《Journal of Quantitative Criminology》2005,21(1):73-102
Prevention science has produced information about risk and protective factors that predict adolescent drug use and related problem behaviors. This paper investigates the Communities That Care Youth Survey that measures multiple risk and protective factors. Using a sample of 172,628 students who participated in surveys administered in seven states in 1998, analyses were conducted to test the factor structure of these risk and protective factors and to test the equivalence of the factor models across five racial/ethnic groups (African Americans, Asians or Pacific Islanders, Caucasians, Hispanic Americans, and Native Americans), four grade levels (6th, 8th, 10th, and 12th) and both gender groups. Results support the construct validity of the surveys risk and protective factor scales and indicate that the measures are equally reliable across males and females and five racial/ethnic groups. Implications of these findings for science-based prevention planning are discussed. 相似文献
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936.
S R Sherman 《Social security bulletin》1985,48(7):27-43
Most new retired workers in 1982 owned some type of asset, usually a savings, checking, or credit union account, according to data obtained by the Social Security Administration (SSA) in its New Beneficiary Survey. Many recently retired workers also owned their home, often mortgage-free. Homeownership was their most significant asset in terms of its median value. Comparatively few retirees owned property other than a home, though for owners of such property, the median value was substantial. Married couples, whose assets included those of both partners, more frequently owned assets and their assets had higher median values than did unmarried individuals. A comparison of retired workers with persons aged 65 or older who were enrolled in the Medicare program but who had not yet received retired-worker benefits showed that these Medicare-only enrollees were much better off, both in the likelihood of owning assets and in having higher median values for their assets. Individuals who retired before reaching age 65 and therefore received a reduced social security benefit were not as well off as those whose first benefit was paid at age 65 or older. Overall, the asset situation of new retired workers in 1982 was better than that of men and unmarried women aged 58-63 in 1969, even when the 1969 assets were adjusted to constant 1982 dollars. 相似文献
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