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近年来,随着我国高速公路的不断延伸,参与高速公路化危品槽车突发事故的抢险救援工作已成为各级消防部队面临的一个新课题,本文从分析掌握高速公路化危品槽车突发事故的特点等5个方面入手,就应采取的抢险救援对策进行了深入探讨。  相似文献   
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Maslen and colleagues offer an excellent model for regulating cognitive enhancement devices (CEDs), and we largely endorse their approach of extending medical device policy to include CEDs. Maslen et al. argue that since the risks and benefits of CEDs can be identified, consumers are best placed to evaluate the impact of these effects on their own wellbeing: ‘experts are to assess what the risks are, the consumer how much they matter’. In principle, we agree: consumers should be allowed to decide what risks are worth taking, but the situation is somewhat more complicated, for the evidence that consumers are in a strong position to evaluate the many risks associated with CED use is lacking. Indeed, a glance at online forums on CEDs suggests that undue risks are already being taken. Importantly, given the ease with which devices can be built using easily obtainable parts, overly tough regulation will not effectively curtail use, but rather push it underground. For these reasons, we suggest that any regulatory framework be buttressed by principles of harm reduction, providing real-world users with expert-backed recommendations for safe use. We argue for the development of tools that facilitate this dialogue, while recognizing the challenges in so doing.  相似文献   
44.
Maslen et al. (2013) have provided us with a comprehensive overview of the current legislation regulating non-clinical cognitive enhancement devices (CEDs) in the European Union and have proposed a specific model whereby CEDs would be regulated in the same way as medical devices. An alternative model would be to require manufacturers to quantify risks only. Irrespective of the purported ‘benefits’ of a product, this would allow the consumer freedom of choice to use the product at their will and allow the periodic review of worthwhile indications and unexpected adverse events. Although this departs from the standard Cochrane-type assessment, it takes into account the facts that (i) the evaluation of clinically used cognitive enhancement techniques may not be as rigorous as one might expect, (ii) variations and case-by-case use might be widespread, and (iii) independent variables of significance and useful endpoints may not be obvious ab initio. We consider cerebrospinal fluid diversion techniques which are widely used clinically to enhance cognition in patients with normal pressure hydrocephalus despite any large-scale clinical studies demonstrating substantial benefit, and the real risks of paralysis and death from these invasive procedures. The risks of CEDs which have been available for some time need to be kept in perspective: are the risks really more than using conventional cognitive enhancement techniques such as imbibing too caffeinated drinks? Furthermore, the loss of Europe as a market for CEDs which do not comply with the proposed regulatory model implies a potential gain in the market for other parts of the world. This could impact on the ability of companies in Europe being able to compete in an evolving market demand for CEDs. Legislation to regulate CEDs should be guided by the principle of ‘do no harm’ and allow for innovation and competition.  相似文献   
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潜血印迹显现方法研究进展   总被引:1,自引:0,他引:1  
潜血印迹一般出现在恶性刑事案件当中,能够反映与案件有关的多方面信息,对于同一认定和分析判断案情具有十分重要的作用,这就使得其显现成为现场勘查的一项必不可少的工作。然而,这也正是公安实践工作当中的难点所在。经过多年的实验研究,目前国内外针对于潜血印迹的显现方法主要包括光学显现法和化学显现法。综述了这些常用显现方法的研究进展,并且讨论了每种显现方法在实践工作当中的优势和不足。  相似文献   
47.
An unknown, viscous, opaque, white liquid with a strong, unpleasant odor was submitted with a request for identification. It was analyzed using infrared (IR) spectroscopy, gas chromatography–mass spectrometry, and X‐ray fluorescence spectroscopy. It was found to contain glycerin as well as another compound. IR and mass spectral data were readily obtained for this second component, but it was not easily identified as common instrument libraries had no matching spectra. After an extensive literature search, the unknown compound was identified as spiromesifen, a recently introduced pesticide. The IR spectrum and electron impact mass spectrum of spiromesifen are presented here as these are not available in the published literature. This case report also provides useful approaches for searching for and identifying an unknown compound when it is not found in a laboratory's spectral libraries.  相似文献   
48.
Urea nitrate (uronium nitrate, UN) is a powerful improvised explosive, frequently used by terrorists in the Israeli arena. It was also used in the first World Trade Center bombing in New York in February 1993. It is difficult to identify UN in postexplosion debris, because in the presence of water it readily decomposes to its original components, urea and nitric acid. A method for the recovery and detection of urea nitrate in traces is described. The residues are extracted with hot acetone, and the extract chromatographed on chromosorb G-HP. The eluent is analyzed by liquid chromatography mass spectrometry using atmospheric pressure chemical ionization (APCI). By applying this technique, we were able to identify urea nitrate in actual exhibits. It was found that UN can be also formed during the analytical procedure, by certain combinations of urea, nitrate ions, and a source of protons and, hence, the presence of the characteristic adduct ion does not necessarily indicate an "authentic" urea nitrate. Several solutions are suggested to overcome this ambiguity.  相似文献   
49.
Fourier transform infrared (FTIR) chemical imaging allows the collection of fingerprint images from backgrounds that have traditionally posed problems for conventional fingerprint detection methods. In this work, the suitability of this technique for the imaging of fingerprints on a wider range of difficult surfaces (including polymer banknotes, various types of paper, and aluminum drink cans) has been tested. For each new surface, a systematic methodology was employed to optimize settings such as spectral resolution, number of scans, and pixel aggregation in order to reduce collection time and file-size without compromising spatial resolution and the quality of the final fingerprint image. The imaging of cyanoacrylate-fumed fingerprints on polymer banknotes has been improved, with shorter collection times for larger image areas. One-month-old fingerprints on polymer banknotes have been successfully fumed and imaged. It was also found that FTIR chemical imaging gives high quality images of cyanoacrylate-fumed fingerprints on aluminum drink cans, regardless of the printed background. Although visible and UV light sources do not yield fingerprint images of the same quality on difficult, nonporous backgrounds, in many cases they can be used to locate a fingerprint prior to higher quality imaging by the FTIR technique. Attempts to acquire FTIR images of fingerprints on paper-based porous surfaces that had been treated with established reagents such as ninhydrin were all unsuccessful due to the swamping effect of the cellulose constituents of the paper.  相似文献   
50.
Two months after the fatal re-entering into the Earth's atmosphere of Columbia flight STS-107, the remains of Israeli astronaut Colonel Ilan Ramon's Crew Notebook were found strewn in a field in San Augustine County, TX. The random pile of papers was found to have survived the calamity of the Shuttle's disintegration remarkably well. Most of the papers recovered were torn and/or washed out to varying degrees but only mildly charred around the edges. The sheets of paper could be categorized into four groups: Group I: eight sides of paper written while in space in black ink and in pencil--Ramon's personal diary; the writing on these eight sides of paper survived well and is only missing where the pages were torn. Small fragments found in the field were physically matched to holes in the pages thus locating their original positions in the text. Group II: six sides of technical preparation notes written by Ramon before the mission. The writing on these pages was washed out entirely, but much of it was visualized using infrared luminescence. Group III: eight sides of personal notes prepared by Ramon before the mission written in blue ink. The writing on these pages was barely visible to the naked eye and not visualized by infrared luminescence, but was made largely legible by digital enhancement imaging. Group IV: a few sides of printed technical information. These pages were mostly intact and were not examined at length as they contained standard printed material. After completion of examinations at the Questioned Document Laboratory of the Israel Police, the diary was transferred to the Paper Conservation Department of the Israel Museum for preservation and strengthening treatments.  相似文献   
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