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Recent research suggests a conditional relationship between states' domestic regimes or ideologies and their alliances. I argue that the likelihood that alliances will form along ideological lines increases with the fear among at least two governments of ideology I that they are threatened by transnational rival ideology J . Understanding the power of demonstration effects—that when J advances in one country it gains credibility in others— I -governments will have an incentive to enter an international agreement to oppose J domestically. Such domestic-security agreements will exacerbate the security dilemma, raising fears among J -governments that I -governments are forming a bloc directed at J and J -governments. J -governments will tend to respond by increasing cooperation among themselves, inducing corresponding fears among I -governments; the coalescing I - and J -blocs will tend to spiral into alliances. I - or J -governments wishing to avoid ideologically based alliances may signal an absence of rollback intentions through various means. I demonstrate this process of alliance formation with a lengthy case study of alliance formation in the Holy Roman Empire in the sixteenth century.  相似文献   
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Environmental samples from indoor surfaces can be confounded by dust, which is composed largely of human skin cells and has been documented to contain roughly tens of micrograms of total DNA per gram of dust. This study complements previous published work by providing estimates of the quantity of amplifiable human DNA found in environmental samples from a typical indoor environment, categorized by the intensity of human traffic and visible quantity of dust. Dust was collected by surface swabbing standard 576 cm2 areas in eight locations, and evaluated for total DNA quantity, presence of human DNA (mitochondrial and nuclear loci using conventional PCR), quantity of human nuclear DNA using quantitative PCR, and STR analysis. The total DNA content of 36 dust samples ranged from 9 to 28 ng/cm2, and contained 0.2–1.1 pg/cm2 of human DNA. Overall, human DNA was detected in 97% of 36 dust samples and 61% of samples yielded allele distributions of varying degrees of complexity when subjected to STR analysis. The implications of this study are twofold. First, the presence of dust in evidence can be a significant contamination source in forensic investigations because the human DNA component is of sufficient quality and quantity to produce allele calls in STR analysis. This can be effectively managed by implementing stringent protocols for collection and analysis of potential biological samples. A second implication is the use of dust as a source of evidence for identification of inhabitants within a defined location. In the latter case, a number of additional studies would be necessary to identify relevant pretreatments for environmental dust samples and to develop the necessary deconvolution techniques to separate the composite genotypes obtained.  相似文献   
4.
Abstract: We tested the hypotheses that foraging insects can acquire human DNA from the environment and that insect‐delivered human DNA is of sufficient quantity and quality to permit standard forensic analyses. Houseflies, German cockroaches, and camel crickets were exposed to dusty surfaces and then assayed for human mitochondrial and nuclear loci by conventional and qPCR, and multiplex STR amplification. Over two experiments, 100% of insect groups and 94% of dust controls tested positive for human DNA. Of 177 individuals, 33–67% tested positive and 13 yielded quantifiable human DNA (mean = 0.022 ± 0.006 ng; mean dust control = 2.448 ± 0.960 ng); four had at least one positive allele call for one or more locus; eight others showed multiple peaks at some loci. Results imply that application to routine forensic casework is limited given current detection methodology yet demonstrate the potential use of insects as environmental samplers for human DNA.  相似文献   
5.
A new method for the detection of caffeine in blood has been proposed based on the combination of extraction and freezing-out to eliminate the influence of sample matrix. Metrological characteristics of the method are presented. Selectivity of detection is achieved by optimal conditions of analysis by high performance liquid chromatography. The method is technically simple and cost-efficient, it ensures rapid performance of the studies.  相似文献   
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Although deterrence theory and social learning theory have been linked on many occasions and are compatible theoretical constructs, criminologists know very little about how the elements of deterrence operate among and between friends. The purpose of this study is to evaluate if similarities in the certainty of sanction, a main element of deterrence, are held between close friends in emerging adulthood. Using data from 1,077 friendship pairs, several confirmatory factor analyses are estimated that attempt to define a friendship-level certainty of sanction construct. Results indicate that friends do not share in common any tendency to perceive similar certainties of sanction. Not only does the certainty between friends fail to load unidimensionally, the two friends’ individual certainty constructs are nearly completely unrelated to each other. In terms of policy implications, peer-based programs targeting increases in sanction certainty tentatively appear to be unnecessary.  相似文献   
7.
A 31-year-old man with migraine-induced syncope and bradycardia with subsequent pacemaker implantation died unexpectedly. Clinically unsuspected cardiac anomalies were found at autopsy including myocardial bridging of the left anterior descending artery and shelf-like coronary artery ostia. Nortriptyline was identified by toxicologic analysis. A review of the autopsy findings, the historical information, and the effects of the possible arrhythmogenic circumstances is undertaken and the potential contributions to the death are discussed. Cardiac arrhythmias have been documented during migraines. Coronary artery bridging has been known to lead to ischemia and infarction, ventricular tachycardia, and sudden death; however, these are very rare sequelae. Congenital coronary artery anomalies have been linked to sudden cardiac death, but only rarely cause death in people younger than 31 years. Migraines and the autopsy findings described have been associated with cardiac arrhythmia and sudden death. Altogether, they led to the unexpected death of this young man.  相似文献   
8.

Purpose

Despite the peer delinquency measurement debate having profound implications for research, looming questions remain about the validity of various forms of peer delinquency operationalizations. This study examines whether perceptions of peer delinquency form identical latent constructs to both respondent and peer self-reported delinquency.

Methods

Using a dyadic dataset of friendship pairs, confirmatory factor analysis and model comparison tests are used to determine the degree of similarity between perceptions of peer delinquency, respondent self-reported delinquency, and peer self-reported delinquency.

Results

Peer self-reports and respondent perceptions of peer delinquency load on unique constructs across a number of different behaviors. For most behaviors, respondent perceptions of peer delinquency and respondent self-reports load on separate constructs. Results further indicate that respondent and peer self-reported delinquency are separate latent constructs. Finally, the strength of the association between respondent and peer delinquency is substantively smaller in magnitude, by as much as a factor of three in some instances, when peer delinquency is measured via peer self-reports in place of respondent perceptions.

Conclusions

Reports of peer delinquency provided directly from peers demonstrate strong discriminant validity in relation to self-reported delinquency, while perceptions of peer delinquency demonstrate poorer discriminant validity, particularly for theft and violence constructs.  相似文献   
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Abstract: This article presents the novel instrumentation of nanomanipulation coupled to nanospray ionization‐mass spectrometry, which is used to directly probe trace analytes found on individual fibers. The low detection limits and sample volumes associated with nanospray ionization‐mass spectrometry make it the ideal instrument to implement for trace analysis. Nanospray ionization‐mass spectrometry, coupled with the nanomanipulator, allows for the direct probing of trace particulates on fibers. The technique is demonstrated by dissolving an electrostatic particle of cocaine from a fiber, collecting the analyte solution in a nanospray tip, and transferring the tip directly to the mass spectrometer to complete analysis. The utility of this technique is evident through the minimal sample preparation and short analysis time. The use of nanomanipulation coupled to nanospray ionization‐mass spectrometry could improve on current trace particulate analysis by reducing both detection limits and sample size required to complete analysis.  相似文献   
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