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71.
    
Spin is the current dominant form of political presentation in the UK. Politics and presentation are inseparable and before the 1980s, political presenters were less aggressive towards and more respectful of journalists as watchdogs of politics. Labour introduced spin as a defensive response to editorial hostility but since New Labour came to terms with Thatcherism, spin has been used for the offensive promotion of policy. Changes in journalism, particularly a blurring treatment of fact and opinion, were an incubatory environment for spin. Moreover, the term became part of lay language and its vocabulary is deployed as a scrutiny of politicians via ridicule and satire. Conceptually, ‘spin’ can be characterised as an exchange or contest between information and publicity, with contingencies influencing where any presentation lies on that continuum. Wherever it falls, spin demeans elected politicians and tends to reduce their status to celebrities. That reduction is a cost too high for privileging presentation over policy and ought to be reversed. Copyright © 2001 Henry Stewart Publications  相似文献   
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73.
    
Data recovery is an important component of digital forensic research. Although recovering data from hard drives or small-scale mobile devices has been well studied, solid-state disks (SSDs) have a very different internal architecture and some additional functions, and it is not clear whether these differences will have an effect on data recovery. Data scrambling is an additional function of an SSD controller which can improve data reliability, but makes data recovery difficult. In this research, the dedicated flash software was first introduced that can acquire the physical image of an SSD without destroying the device hardware. Based on the software, a validation experiment was presented to evaluate the effect of data scrambling on data recovery and the causes of the effect were analyzed. Then two approaches to descrambling the data in the flash chips were proposed and their advantages and disadvantages discussed. After that, a procedure to identify the scrambling seeds that are used to descramble the scrambled data was described. Finally, descrambling software was implemented based on the second descrambling method. The experiment shows that this software can successfully descramble the data from an SSD flash drive regardless of the internal structure of the scrambler in the SSD controller and can generate an unscrambled physical image on which most existing data-recovery techniques can be effective.  相似文献   
74.
    
Lawful Interception (LI) of data communications is an essential tool for Law Enforcement Agencies (LEA) in order to investigate criminal activities carried out or coordinated by means of Internet. However, the ability to secretly monitor the activities of citizens also has a great impact on civil rights. Therefore, democratic societies must prevent abuse and ensure that LI is only employed in specific cases with justifiable grounds or a probable cause. Nowadays, in many countries each interception must be authorized by a wiretap warrant, usually issued by a judge. However, this wiretap warrant is merely an administrative document that should be checked by the network or service operator before enabling the monitoring of its customers, whose communications are later handed over to a LEA in plaintext. This paper proposes the idea of employing a Digital Wiretap Warrant (DWW), which further protects the civil liberties, security and privacy of LI by ensuring that monitoring devices can only be enabled with a valid DWW, and by encrypting the captured data so only the authorized LEA is able to decrypt those communications. Moreover, in the proposed DWW framework all digital evidence is securely time-stamped and signed, thus guaranteeing that it has not been tampered with, and that a proper chain of custody has been met. In particular this paper proposes how to apply the DWW concept to the lawful interception framework defined by the ETSI LI Technical Committee, and evaluates how the additional security mechanisms could impact the performance and storage costs of a LI platform.  相似文献   
75.
    
Forensic practitioners and crime laboratories regularly collect and analyze fingernail evidence; however, the best techniques for processing such evidence have not been established. In this study, numerous aspects of fingernail evidence processing—collection of exogenous cells, transportation, purification of DNA, and STR analysis—were analyzed using fingernails harboring applied blood or epithelial cells from scratchings. Autosomal STR mixtures resulted when fingernails were soaked or swabbed, while scrapings rarely generated mixtures but exhibited allelic dropout. Y‐STRs yielded single source profiles, with scrapings again showing dropout. A silica‐based kit extraction recovered significantly more exogenous DNA than did organic extraction, neither of which was affected by nail polish. Swabbing nails in succession resulted in some cross‐contamination from exogenous material, while transporting nails together did not, although there was loss of exogenous cells. Optimized nail processing produced complete Y‐STR profiles of male volunteers from female fingernails following scratchings.  相似文献   
76.
    
Refractive indices of seven double‐paned vehicle windshields were measured to assess the variation across the pane of glass and to evaluate collection techniques for known glass standards by comparing false negative rates. Measurements were made using a Foster and Freeman GRIM3 instrument, and a minimum of 240 measurements were made per pane. The mean SD of the windshields was 0.00004. It was further determined that collecting a known sample from two different sections of a shattered windshield gave the lowest rate of false negatives when using ± 2 standard deviations to estimate the RI variation of the known glass. Additionally, refractive indices often were highest in the center of the windshield and decreased toward the left and right edges; in approximately half the sample set, the two panes of a single windshield were differentiated by one or more properties.  相似文献   
77.
以英美法系和我国司法实践中鉴定人角色差异为视野,深入探讨DNA证据应用领域中的三个经典命题的推导主体,明确鉴定人在DNA证据应用中的职责权限,避免DNA证据被错误解读和应用,并尝试以证据的相关性、可采性和证明力为基础,探讨我国司法实践中DNA证据正确应用的途径.  相似文献   
78.
    
Comparative analyses of 50 single‐layer white architectural paints were conducted to determine the discrimination power using standard techniques and to provide a basis for assessing significance when paints with limited features are not discriminated. Utilizing Fourier transform infrared spectroscopy (FTIR), 68 undifferentiated pairs resulted, yielding a discrimination of 94.45%. Adding stereomicroscopy, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and backscatter electron (BSE) imaging, and pyrolysis‐gas chromatography/mass spectrometry (Py‐GC/MS), the overall discrimination was 99.35%. The study included blind verification replicates, which resulted in the only pairs without indications of physical or chemical differences. The remaining groups of undifferentiated samples contained subtle differences by at least one technique, but were considered undifferentiated for the discrimination power evaluations. This study demonstrates a high degree of discrimination of single‐layer white architectural paints using methods of analysis often encountered in forensic science laboratories.  相似文献   
79.
    
Fibers are a commonly encountered evidence type and fiber comparisons are routinely conducted. When the characteristics of questioned and known fibers correspond, the probative value is limited because the characteristics compared are determined by their manufacture. It would be valuable to test the hypothesis that questioned fibers originated from a specific carpet. One means of testing this is to analyze fine particles on the fibers. A procedure was developed for removing adhering particles from fibers and preparing them for scanning electron microscopy/ energy dispersive X‐ray spectrometry (SEM/EDS) analysis. The efficacy of several fluids (acetone, ethanol, hexanes, aqueous ethanol, aqueous sodium hexametaphosphate) and agitation methods (sonication and vortexing) for removing particles from fibers was evaluated. The most effective method evaluated was sonication in ethanol for 10 min. The recovered particles were filtered onto a polycarbonate filter and analyzed by automated SEM/EDS analysis to generate data on the particle assemblage. This method makes possible future research to test the within‐item and between‐item variability of particle assemblages on fibers.  相似文献   
80.
    
Performance of likelihood ratio (LR) methods for evidence evaluation has been represented in the past using, for example, Tippett plots. We propose empirical cross‐entropy (ECE) plots as a metric of accuracy based on the statistical theory of proper scoring rules, interpretable as information given by the evidence according to information theory, which quantify calibration of LR values. We present results with a case example using a glass database from real casework, comparing performance with both Tippett and ECE plots. We conclude that ECE plots allow clearer comparisons of LR methods than previous metrics, allowing a theoretical criterion to determine whether a given method should be used for evidence evaluation or not, which is an improvement over Tippett plots. A set of recommendations for the use of the proposed methodology by practitioners is also given.  相似文献   
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