Determination of total hemoglobin in forensic blood samples with special reference to carboxyhemoglobin analysis

For the determination of total hemoglobin (Hb) in blood containing elevated carboxyhemoglobin (COHb), a newly developed reagent containing a 100-fold concentration of ferricyanide (20 g/l) and a 2-fold concentration of Sterox SE was compared with a standard reagent (0.2 g/l ferricyanide), the reagent of van Kampen and Zijlstra, using forensic blood samples and experimentally heated blood samples. There were no significant differences between the spectra of hemiglobincyanide (HiCN) solution produced with our reagent and the van Kampen and Zijlstra reagent using experimentally heated blood samples. Although the spectra of HiCN changed gradually with increased heating time and with the passage of time after mixing, the absorbance at 540 nm (A540) did not change until at least 120 min for both the reagents. When forensic blood samples containing elevated COHb were mixed with the van Kampen and Zijlstra reagent, total-Hb concentrations determined 5 min after mixing were 10-20% higher than those determined after 180 min. The overestimates of total Hb determined after 5 min resulted in comparable underestimates of percentage saturation of COHb (COHb%) when COHb% was obtained from the ratio of COHb content, determined by gas chromatogrpahy, to total-Hb concentration in blood. However, there was an extremely good correlation between the values of total Hb in forensic blood samples determined with the van Kampen and Zijlstra reagent after 180 min and those determined with our reagent after 5 min. From the results obtained, our reagent proved to be suitable for the determination of total Hb in forensic science practice.     

Private Representation in Washington: Surveying the Structure of Influence

Despite the significance of interest representation to theories of law and politics, the social organization of interest representation has not received systematic empirical analysis. Based on interviews with 776 individuals engaged in the representation of private interests concerning national policies on agriculture, energy, health, and labor, this article reports some findings concerning the social and political characteristics of representatives, the nature of their work and their relationships with client organizations. Three models of the social organization of interest representation are developed and examined: a model based on substantive expertise, an institutional targets model, and a client-based model. The findings indicate that representation is predominately organized around client interests Although lawyers constitute a significant and distinctive group among representatives, they are neither as numerous nor as active in policy making as is commonly assumed. The analysis suggests that representatives are not likely to exercise influence in the policy-making process that is autonomous from client organizations.