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921.
Rens Vliegenthart Stefaan Walgrave Brandon Zicha 《European Journal of Political Research》2013,52(3):390-418
In this article an integrated framework of agenda‐setting is proposed that incorporates the two main accounts of agenda‐setting: the information‐processing approach by Comparative Agenda Project scholars and the preference‐centred account advanced by Comparative Manifestoes Project scholars. The study claims that attention allocation is determined at the same time by preferences, information and institutions, and that attention allocation is affected by the interactions between these three factors. An empirical test is conducted that draws upon a dataset of parliamentary questions/interpellations in Belgium in the period 1993–2000. It is found that attention in parliament is indeed driven by preceding party manifestos (preferences), by available information (media coverage) and by institutional position (government or opposition party). The evidence establishes that agenda‐setting is also affected by the interactions between preferences, information and institutions. Actors, given their preferences, treat information in a biased fashion, and institutions moderate information's role. 相似文献
922.
《Critical Horizons》2013,14(2):127-155
AbstractFrom the late seventeenth century on the idea of culture underwent a gradual transformation. Originally this concept referred essentially to the “refined” way of life of the ruling social elite (which certainly included among others also such activities as listening and making music, reading works of literature, commissioning works of fine art). Popular culture, on the other hand, refers to the usually collective practices of groups of rural and urban workers taking the form of performance. They were not only excluded from refined culture, but it was regarded as completely unsuitable for them, potentially creating dangerous social aspirations. It is with the great social transformation from feudal to bourgeois society that the idea of refined culture was replaced by that of “high culture” encompassing both the arts and the sciences: works claiming universal human significance. This “high culture” for a considerable time coexisted with the remnants of popular culture. It has been only due to the great technical advances that its true opposite, “mass culture” emerged, at the turn to twentieth century, claiming an empirical universality: being understandable and truly interesting to everyone. In economic respect, there is a competitive relation between high and mass culture. However, it is argued that there can be no cultural competition between them. For they posit differing and potentially co-existing receptive attitudes. The characterisation of this difference and the discussion of the seeming exceptions to the so-articulated conceptual scheme occupies the concluding part of this essay. 相似文献
923.
In this study, δ13C values of six cocaine samples were identified and classified using a single quadrupole mass spectrometer and an isotope ratio mass spectrometry (IRMS) as simultaneous gas chromatography detectors. Our instrument modification is simple to use and is useful (i) when the sample is of limited size or can only be injected once, (ii) to help identify peaks in a complicated IRMS chromatogram, and (iii) to help differentiate very simple systems when impurity profiling is not possible. The EI-MS confirmed the identity of cocaine in each sample. The IRMS data distinguished 12 of the 15 possible pair-wise comparisons at the 95% CL. Three samples could not be differentiated by their δ13C ratios for cocaine. ANOVA demonstrated that the measurement variance was consistently larger than the sample variance. As the δ13C values clearly show, this technique enables the exclusion of a potential common source even when two samples have otherwise identical chemical and physical properties. 相似文献
924.
Successful DNA-based identification of mass disaster victims depends on acquiring tissues that are not highly degraded. In this study, multiple protocols for field preservation of tissues for later DNA analysis were tested. Skin and muscle samples were collected from decaying pig carcasses. Tissues were preserved using cold storage, desiccation, or room temperature storage in preservative solutions for up to 6 months. DNA quality was assessed through amplification of successively larger segments of nuclear DNA. Solution-based storage, including a DMSO/NaCl/EDTA mixture, alcohols, and RNAlater preserved DNA of the highest quality, refrigeration was intermediate, and desiccation was least effective. Tissue type and extent of decomposition significantly affected stored DNA quality. Overall, the results indicate that any tissue preservation attempt is far superior to delaying or forgoing preservation efforts, and that simple, inexpensive methods can be highly effective in preserving DNA, thus should be initiated as quickly as possible. 相似文献
925.
This study involved the comparative analysis and discrimination of 90 electrical tape adhesives. The objectives included the evaluation of the ability of individual techniques to discriminate samples and the assessment of the ability of the techniques combined to distinguish samples. The techniques utilized were stereomicroscopy, Fourier transform infrared spectroscopy (FTIR), pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS). Stereomicroscopy, to assess adhesive colors of black, clear/colorless, and clear adhesives with brown tint, resulted in a discrimination of 53%. FTIR analysis yielded eight distinct groups with a discrimination of 67%. Py-GC/MS analysis resulted in 16 groups with a discrimination of 83%. These analyses confirmed and further subdivided the FTIR groups. SEM/EDS resulted in five separate groups at 17% discrimination, increasing the overall discrimination to above 85%. 相似文献
926.
Porcine tissue samples shot with two different types of bullets, jacketed and nonjacketed, were collected in the fresh state and throughout moderate decomposition. Wound samples were microwave-digested and analyzed using inductively coupled plasma mass spectrometry (ICP-MS) to detect all elements present at measurable levels in gunshot residue (GSR). Elements detected included antimony (Sb), barium (Ba), and lead (Pb), which are considered characteristic of GSR, as well as iron (Fe) and copper (Cu). These five elements were used to differentiate shot tissue and unshot tissue, as well as tissue shot by the two different bullet types, both in the fresh state and throughout moderate decomposition. The concentrations of Cu, Sb, and Pb were able to distinguish the two bullet types in fresh tissue samples at the 95% confidence level. Cu and Pb were able to differentiate the bullet types throughout moderate decomposition at the 99% confidence level. 相似文献
927.
Shannon E. May M.A. 《Journal of forensic sciences》2011,56(1):3-9
Abstract: Cremains have become increasingly frequent in forensic contexts, while higher body mass in the general population has simultaneously made cremation a more cost‐effective mortuary practice. This study analyzed the relationship between body mass and bone mass, as reflected through cremation weight. Antemortem data were recorded for samples used in the multi‐regional data set. Each was rendered through commercial crematoriums and reweighed postincineration. Pearson’s correlation demonstrates clear association between body mass and cremation weight (r = 0.56; p < 0.0001). However, multiple linear regression revealed sex and age variables also have a significant relationship (t = 7.198; t = ?2.5, respectively). Regressed in conjunction, body mass, sex, and age contribute approximately 67% of all variation observed in cremation weight (r = 0.668). Analysis of covariance indicates significant regional variation in body and cremation weight. Explanations include bone modification resulting from increased loading stress, as well as glucose intolerance and altered metabolic pathways related to obesity. 相似文献
928.
Lubricating oil comparisons impact a variety of forensic investigations, including cases where oil was transferred from a suspect vehicle to the crime scene or victim. In this study, high-temperature gas chromatography/mass spectrometry was used to examine the influence of oil mixtures and oil changes over time on the comparison of known and questioned lubricating oils. Varying concentrations of oil mixtures were prepared and showed the potential for identifying individual components. Motor oils from 18 automobiles monitored over a 2-month period did not demonstrate significant changes in the chromatographic data. Chemometric analysis of motor oil mass spectral data provided little information regarding differentiation of, or changes in, the samples. Power steering fluid (PSF) from a naturally occurring leak collected from several locations was consistent with the PSF in the automobile's reservoir, and the PSF composition did not change over time. 相似文献
929.
目的建立血样中4种常见巴比妥类药物的固相萃取方法。方法采用Oasis MAX固相萃取柱对样品进行预处理,以2%氨水淋洗2,%甲酸-甲醇洗脱,GC/NPD定量检验,GC/MS定性检验。结果血样中4种常见巴比妥类药物平均萃取回收率达80%以上,以信噪比10/1计,最小定量限为1~2μg/mL,以信噪比3/1计,检出限为0.5~1μg/mL,在1~50μg/mL范围内,线性相关系数均在0.99以上。结论本文固相萃取方法检出限低,回收率高,选择性强,可应用于血样中4种常见巴比妥类药物的检测。 相似文献
930.
Abstract: A 15‐year‐old male orally consumed an unknown but fatal amount of sustained release hydromorphone. He was naïve to opioid use. No other drugs or alcohol were involved. The cause of death was acute aspiration‐related bronchopneumonia, secondary to hydromorphone ingestion; the manner of death was accidental. Hydromorphone and hydromorphone‐3‐glucuronide were quantified in postmortem fluids by tandem liquid chromatography–mass spectrometry. The hydromorphone concentrations in the peripheral blood, urine, and vitreous humor were 57, 4460, and 31 ng/mL, respectively. The hydromorphone‐3‐glucuronide concentrations in the corresponding three fluids were 459, 36,400, and 40 ng/mL. Hydromorphone‐3‐glucuronide accumulation probably did not contribute significantly to the opiate toxicity. The proposed minimum lethal hydromorphone blood concentration in the nontolerant user is in the vicinity of 60 ng/mL. 相似文献