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251.
Validation of a recently proposed differentiation method for single poly (ethylene terephthalate) (PET) fibers, based on integration of IR absorption bands, is presented. IR microscopy in the transmission mode, differential scanning calorimetry and optical microscopy were employed. The reliability of the technique has been extended to the cases in which the fibers being compared have experienced long exposure to the elements, as may happen if these items are recovered from open-air crime scenes. The effect of immersion in water and irradiation by the sun for a three-month period have been considered. The fibers remained morphologically and structurally unaltered. The significance of comparisons between fibers kept in different environments is thus enhanced, because the detrimental effect of the elements can be ruled out. This further validation of the proposed technique contributes to render the data presented by the forensic scientist less vulnerable to context effect and bias.  相似文献   
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253.
Gelatin lifter is widely used for recovering shoeprints from crime scenes. Dusty shoeprints removed from paper with loose fibers, cloth or plasterboard, might be concealed by the detached fibers. A novel technique to clean the gelatin lifter from the interfering contaminations, using adhesive lifters, was developed. The adhesive lifter is applied directly on the surface of the gelatin lifter, and is removed instantly. The adhesive lifter removes the upper layer of the attached material on the gelatin lifter. After removing the concealing material from the hidden imprint, the quality of the visualized imprint is improved. The cleaning process can be applied as many times as needed and the optimum number is different for each substrate. The small dust particles comprising the shoeprint remained attached to the sticky side of the gelatin lifter even though the adhesion force applied by the adhesive lifter is great. Repeating the procedure too many times could harm the quality of the print severely, yet the advantages of this method are greater than the risks of relocation of image quality reduction.  相似文献   
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A collaborative study on Raman spectroscopy was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on three dyed fibers: two red acrylics and one red wool. Raman instruments from six different manufacturers were tested as well as nine different laser wavelengths ranging from blue (lambda = 458 nm) to near infrared-NIR (lambda = 1064 nm). This represents the largest comparison study of Raman analytical parameters carried out on identical fiber samples. For the chosen fiber and dye samples, red lasers (lambda = 633 and 685 nm) gave the poorest spectral quality whereas blue (458 nm), green (514 nm) and near infrared lasers (785, 830 and 1064 nm) provided average results. Blue (488 nm) and green lasers (532 nm) globally gave the best quality spectra. Fluorescence problems were often encountered with some of the excitation wavelengths and therefore a flexible Raman instrument equipped with different lasers can be recommended to measure forensic fiber samples. The instrument should also be equipped with a Raman microscope in order to be able to focus on a single fiber. This study shows that Raman spectroscopy usually enables the identification of the main dye present in a colored fiber; however, minor dye components are much more difficult to detect. SERRS (Surface Enhanced Resonance Raman Scattering) techniques give an improvement of the dye's spectral intensity but no spectral improvement was observed for the two red acrylic and red wool fibers tested.  相似文献   
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The U.S. Office of Personnel Management (OPM) is issuing a final regulation amending the Federal Employees Health Benefits (FEHB) Acquisition Regulation (FEHBAR). This regulation provides additional contract cost principles and procedures for FEHB Program experience-rated contracts and is intended to clarify our requirements and enhance our oversight of FEHB carriers.  相似文献   
258.
This paper describes an effort to develop a clinical tool for the continuous monitoring of risk for violence in forensic mental health clients who have left their institutions and who are dwelling in the community on a conditional release basis. The model is called Structured Outcome Assessment and Community Risk Monitoring (SORM). The SORM consists of 30 dynamic factors and each factor in SORM is assessed in two ways: The current absence, presence or partial och intermittent presence of the factors, which is an actuarial (systematized and 'objective') assessment. Secondly, the risk effect, i.e. whether the presence/absence of factors currently increases, decreases or is perceived as unrelated to violence risk, is a clinical (or impressionistic) assessment. Thus, the factors considered via the SORM can be coded as risk factors or protective factors (or as factors unimportant to risk of violence) depending on circumstances that apply in the individual case. Further, the SORM has a built-in module for gathering idiographical information about risk-affecting contextual factors. The use of the SORM and its potential as a risk monitoring instrument is illustrated via preliminary data and case vignettes from an ongoing multicenter project. In this research project, patients leaving any of the 9 participating forensic hospitals in Sweden is assessed at release on a variety of static background factors, and the SORM is then administered every 30 days for 2 years.  相似文献   
259.
The purpose of this article is to use the ideas of path dependency to understand why policies implemented by governments for health care in England were and are suboptimal in terms of the control of total costs, the equitable distribution of hospital services, and efficiency in delivery. We do this by relating the economic logic of achieving these objectives to the political logic of a state-hierarchical system in which ministers are accountable for the effects of policies and doctors largely decide the supply and demand of health care. The initial policy path of the National Health Service (NHS) controlled costs but lacked systems to achieve equity and efficiency in the funding of hospitals. Policies were introduced to achieve equity, but not efficiency, in the 1970s. The Thatcher government sought efficiency through a budgetary squeeze in the 1980s, which culminated in the NHS funding crisis of 1987 - 1988. The result was the policies of the NHS internal market, which promised efficiency by introducing a purchaser-provider split and a system of provider competition in which money would follow the patient. These promises justified an injection of extra funds for three years, but only a pallid model of the internal market was implemented. The Blair government abandoned the rhetoric of competition but maintained the purchaser-provider split and continued to constrain total NHS costs, which resulted in the funding crisis of 1998 - 1999. Current policies are to substantially increase spending on health care and reintroduce a system of provider competition in which money will follow the patient.  相似文献   
260.
Experimental data useful for the interpretation of paint evidence recovered during burglary cases were obtained. A population study was carried out on 41 blue crowbars seized on suspects in Switzerland and 37 blue paints traces found at burglary scenes. Paint traces were also searched on the blades of 207 crowbars seized by the police in Switzerland and 24 white traces were analysed: these paints were analysed using infrared spectroscopy (FTIR) in order to estimate relative frequencies of each paint type. Simulated contacts were carried out between crowbars and painted wood in order to study the phenomenon of transfer and to evaluate the amount of paint transferred: a total of 198 simulations were carried out including individual, successive and cross transfer. The paint properties such as the chemical composition and its age influenced the amount of paint transferred. Cross transfer from the tool paint to the wood and vice versa was regularly observed. Moreover, secondary transfer of paint coming from the preceding wooden surfaces was also systematically observed: this could establish links between several burglary scenes and a suspected tool. A scenario of a burglary case involving the cross transfer between tool and household paints is proposed as a numerical example: the evaluation of such case was formalised using likelihood ratios based on the experimental data obtained.  相似文献   
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