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201.
This paper examines a central regulatory mechanism that shapes food economies. Food safety regulations in the United States rely on a science‐based transnational regulatory system known as Hazard Analysis and Critical Control Point (HACCP), which bears central features of what Sabel and Zeitlin identified as experimentalist governance: a new form of regulation that is flexible, responsive, and involves stakeholders in iterative and direct democratic deliberation. The core theoretical question the paper examines is what the reliance on science means for the promise of an experimentalist policy regime to enable a new form of democratic politics. Based on a case study of the HACCP system implemented by the US Department of Agriculture's Food Safety and Inspection Service since the late 1990s, HACCP's reliance on food science has acted as an effective divider between producers who were able to take advantage of the system's flexibility and others for whom this was challenging. There is clear evidence that HACCP posed a disproportionate burden on small processors and that some of them were unable to adapt to the requirements of the regulatory system. In so far as the HACCP‐based food safety regulations delineated the kind of producer that thrived in the system and contributed to the demise of another set of producers, the regulatory system shaped market outcomes.  相似文献   
202.
The spatial expression of urban centrality in big cities is generally associated with several urban nodes. The major purpose of this article is to identify the spatial pattern of urban sub‐centres in Mexico City during the period 1989–2009 and how changes in urban centrality have given way to a more polycentric urban structure. A double‐threshold method was used for comparing the polycentric structure of a single city over time examining the variables of number of jobs and tertiary employment density; this approach for identifying employment centres is proven in a megacity of a developing country.  相似文献   
203.
In this article, I argue that kin states can play major roles in international mediation processes involving their kin communities. Although kin states may be naturally biased toward their kin, kin states are sometimes actively involved in mediation processes and such involvement is even encouraged by third‐party mediators. In this study, I divide the various roles assumed by kin states in mediation into four main conceptual categories: promoter, quasi‐mediator, powerbroker, and enforcer. My analysis presumes that a kin state can use its close ties with its kin community to make third‐party mediation more successful. I support and illustrate this model using cases of kin‐state involvement in peace processes and examine both the benefits and complications that kin‐state mediation can entail. This study contributes to scholarship examining the effectiveness of biased mediators. I conclude that the role a kin state assumes in a mediation is often context‐dependent, but that third‐party mediators and the international community can use their leverage over kin states to improve the peace process.  相似文献   
204.
The usage of herbal incenses containing synthetic cannabinoids has caused an increase in medical incidents and triggered legislations to ban these products throughout the world. Law enforcement agencies are experiencing sample backlogs due to the variety of the products and the addition of new and still‐legal compounds. In our study, proton nuclear magnetic resonance (NMR) spectroscopy was employed to promptly screen the synthetic cannabinoids after their rapid, direct detection on the herbs and in the powders by direct analysis in real time mass spectrometry (DART‐MS). A simple sample preparation protocol was employed on 50 mg of herbal sample matrices for quick NMR detection. Ten synthetic cannabinoids were discovered in fifteen herbal incenses. The combined DART‐MS and NMR methods can be used to quickly screen synthetic cannabinoids in powder and herbal samples, serving as a complementary approach to conventional GC‐MS or LC‐MS methods.  相似文献   
205.
Time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) is a well‐established surface technique that provides both elemental and molecular information from several monolayers of a sample surface while also allowing depth profiling or image mapping to be performed. Static TOF‐SIMS with improved performances has expanded the application of TOF‐SIMS to the study of a variety of organic, polymeric, biological, archaeological, and forensic materials. In forensic investigation, the use of a minimal sample for the analysis is preferable. Although the TOF‐SIMS technique is destructive, the probing beams have microsized diameters so that only small portion of the questioned sample is necessary for the analysis, leaving the rest available for other analyses. In this study, TOF‐SIMS and attenuated total reflectance Fourier transform infrared (ATR‐FTIR) were applied to the analysis of several different pen inks, red sealing inks, and printed patterns on paper. The overlapping areas of ballpoint pen writing, red seal stamping, and laser printing in a document were investigated to identify the sequence of recording. The sequence relations for various cases were determined from the TOF‐SIMS mapping image and the depth profile. TOF‐SIMS images were also used to investigate numbers or characters altered with two different red pens. TOF‐SIMS was successfully used to determine the sequence of intersecting lines and the forged numbers on the paper.  相似文献   
206.
In forensic science, biological material is typically collected from evidence via wet/dry double swabbing with cotton swabs, which is effective but can visibly damage an item's surface. When an item's appearance must be maintained, dry swabbing and tape‐lifting may be employed as collection techniques that are visually nondestructive to substrates' surfaces. This study examined the efficacy of alternative swab matrices and adhesive lifters when collecting blood and fingerprints from glass, painted drywall, 100% cotton, and copy paper. Data were evaluated by determining the percent profile and quality score for each STR profile generated. Hydraflock® swabs, BVDA Gellifters®, and Scenesafe FAST? tape performed as well as or better than cotton swabs when collecting fingerprints from painted drywall and 100% cotton. Collection success was also dependent on the type of biological material sampled and the substrate on which it was deposited. These results demonstrated that alternative swabs and adhesive lifters can be effective for nondestructive DNA collection from various substrates.  相似文献   
207.
One of the crucial factors determining the cyanoacrylate deposit quality over latent fingerprints appeared to be the extent of the humidity. This work focuses on the enhancement/refreshment of age‐degraded latent fingerprints by irradiating the samples with UV, X‐ray, or thermal neutrons prior to the cyanoacrylate (CA) fuming. Age degradation of latent fingerprints deposited on glass surfaces was examined through the decrease in the number of characteristic minutiae counts over time. A term “critical day” was introduced for the time at which the average number of identifiable minutiae definitions drops to one‐half. Fingerprints older than their “critical day” were exposed to either UV, X‐ray, or thermal neutrons. Identical reference samples were kept unexposed. All samples, both reference and irradiated, were developed during a single CA fuming procedure. Comparative latent fingerprint analysis showed that exposure to ionizing radiation enhances the CA fuming, yielding a 20‐30% increase in average minutiae count.  相似文献   
208.
Concerns over the toxic by‐products produced by traditional ammunition have led to an increase in popularity of nontoxic ammunition. In this work, the chemical composition of six brands of nontoxic ammunition was investigated and compared to that of a road flare, which served as an environmental source with similar composition. Five rounds of each brand were fired while a further five were disassembled and the primer alone was fired. Particles collected from all samples, including the road flare, were analyzed by scanning electron microscopy with energy dispersive X‐ray analysis. Common elements among the different ammunition brands included aluminum, potassium, silicon, calcium, and strontium. Spectra were then subjected to principal components analysis in which association of the primer to the intact ammunition sample was generally possible, with distinction among brands and from the road flare sample. Further, PCA loadings plots indicated the elements responsible for the association and discrimination observed.  相似文献   
209.
210.
Estimation of time of death is an indispensible requirement of every medico‐legal autopsy, but unfortunately, there is not a single method by which it could be determined accurately. This study focused on the temperature‐dependent postmortem degradation of cardiac troponin‐T and its association with postmortem interval (PMI) in human. The analysis involved extraction of the protein, separation by denaturing gel electrophoresis (SDS‐PAGE), and visualization by Western blot using cTnT‐specific monoclonal antibodies. The area of the bands within a lane was quantified by scanning and digitizing the image using Gel Doc (Universal Hood). The results indicate a characteristic banding pattern among human cadavers (n = 6) and a pseudo‐linear relationship between percentage of cTnT degradation and the log of the time since death (r > 0.95), which can be used to estimate the postmortem interval. The data presented demonstrate that this technique can provide an extended time range during which PMI can be more accurately estimated.  相似文献   
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