The Stability of Collected Human Scent Under Various Environmental Conditions*,†

Abstract: Human scent evidence collected from objects at a crime scene is used for scent discrimination with specially trained canines. Storage of the scent evidence is usually required yet no optimized storage protocol has been determined. Storage containers including glass, polyethylene, and aluminized pouches were evaluated to determine the optimal medium for storing human scent evidence of which glass was determined to be the optimal storage matrix. Hand odor samples were collected on three different sorbent materials, sealed in glass vials and subjected to different storage environments including room temperature, ?80°C conditions, dark storage, and UVA/UVB light exposure over a 7‐week period. Volatile organic compounds (VOCs) in the headspace of the samples were extracted and identified using solid‐phase micro‐extraction–gas chromatography/mass spectrometry (SPME–GC/MS). Three‐dimensional covariance mapping showed that glass containers subjected to minimal UVA/UVB light exposure provide the most stable environment for stored human scent samples.     

Does Acceptability of Violence Impact the Relationship Between Satisfaction,Victimization, and Commitment Levels in Emerging Adult Dating Relationships?

This study examined the impact of acceptability of violence on dating violence victimization, relationship satisfaction, and relationship commitment. A survey administered to a sample of 155 male and 417 female college students showed that relationship satisfaction was significantly associated with relationship commitment, but that dating violence victimization was not. Moreover, acceptability of violence emerged as a significant moderator of the relationship between satisfaction and commitment in dating relationships when gender differences were assessed. Discussion of these findings and future research are included.

舆情控制化解群体性事件初探

2008年发生在贵州的翁安事件、云南的胶农事件,引起各级政府及民众的一片哗然,特别是给全国的公安机关敲响了警钟。随着我国进入社会转型期,加之全球经济危机的影响,各种社会矛盾日益凸现。一些地方政府片面追求经济效益,领导干部对群众的感情冷淡麻木,人民群众的利益诉求长期得不到解决,必然导致群体性事件发生。这不仅造成了严重的负面社会影响,而且还造成了巨大的经济财产损失。如何巧妙处置群体性事件,已成为对公安机关的严峻考验。笔者认为,可以在我国社会主义转型期建立舆情导控员制度,通过正确、合理引导群众舆论,来达到化解群体性事件发生的目的。     

毛泽东群众运动理论与中央苏区五次反“围剿”

五四运动后,中国革命的主体发生了重大转变,中国工人阶级取代民族资产者成为革命的领导者。毛泽东经过五四运动和组织领导湖南工农运动,在开辟井冈山和赣南闽西根据地的斗争中,初步形成了“工农武装割据”的群众运动理论,经历了中央苏区五次反“围剿”斗争的实践检验以后,成为他后来思考马克思主义中国化的出发点。     

Legislative strength and democratic satisfaction in presidential democracies

The gap between electoral winners and losers in democratic satisfaction has been well documented in the literature. Scholars further argue that in consensual systems, where the institutional design involves more power sharing, the winner-loser gap is smaller than in majoritarian systems. However, how the powers of legislatures, the primary national-level agency to impose restraints on the executive, affect the winner-loser gap has not been thoroughly studied. Utilizing data of 29 countries in the world over ten years, this paper verifies that in presidential democracies, when legislatures have more oversight power, the winner-loser gap in satisfaction tends to be reduced. The relationships are particularly evident when opposition parties have distinct policy platforms, as these oppositions are better able to utilize the legislative arena to voice their positions. Furthermore, the effect of legislative strength on losers’ consent is more pronounced among voters who are more interested in politics.     

Having a say or getting your way? Political choice and satisfaction with democracy

Citizen satisfaction with democracy is greater when parties offer choices that are congruent with voter preferences. But are citizens content with simply having a party that represents their views or does their satisfaction depend on whether that party can also be instrumental in implementing policies? We argue that instrumentality moderates the effect of ideological congruence on democratic satisfaction. Combining an analysis of cross-national survey data with an experimental conjoint design, we find that citizens able to vote for a congruent party with a chance of entering government are more satisfied with democracy, whereas congruence without instrumentality has no such effect.     

Desorption electrospray tandem MS (DESI-MSMS) analysis of methyl centralite and ethyl centralite as gunshot residues on skin and other surfaces

Abstract:  A direct and sensitive method for the detection of methyl centralite (MC) and ethyl centralite (EC) as gunshot residues (GSRs) has been developed. This method uses desorption electrospray ionization (DESI)-tandem mass spectrometry and directly desorbs and detects analytes from surfaces without any sampling process. Typical transitions for MC and EC, m/z 241 to m/z 134 and m/z 269 to m/z 148, respectively, were used to improve the assay sensitivity. It has been shown that MC and EC can be detected on various surfaces, with detection limits of 5–70 pg/cm². Interferences, detection time after shooting and the number of times hands were washed after shooting were also evaluated. None of the materials interfered with the results and the detection window for organic GSRs was up to 12 h and hands could be washed at least six times. Further samples were analyzed to confirm the reliability of this method, and showed that it could discriminate shooters from nonshooters. This method should be of significance in forensic science, especially in analyzing GSRs, because of its simplicity, high throughput, and the direct detection of MC and EC on suspects' hands, clothes, and hair.     

An investigation into the spatial elemental distribution within a pane of glass by time of flight secondary ion mass spectrometry

Advances in the technology employed for the manufacture of glass have resulted in a final glass product with little variability in terms of its physical and optical properties. For example, the refractive index of Australian float glass tends to lie between 1.5189 and 1.5194. It has therefore become necessary to complement physical and optical methods for forensic glass comparison with instrumental elemental analyses. In a previous study, time-of-flight secondary ion mass spectrometry has been shown to offer potential for the analysis of glass particles as small as a few tens of microns across. In this study, the three-dimensional homogeneity of a sheet of float glass is described, and consequences for forensic elemental analysis of glass particles of such size are explored. Variation in Si, Ca, Mg, and Na levels immediately under the nonfloat surface was observed, with the variance accompanied by a decrease in refractive index.     

A case study on the application of isotope ratio mass spectrometry (IRMS) in determining the provenance of a rock used in an alleged nickel switching incident

The application of isotope ratio mass spectrometry (IRMS) in forensic science to establish the provenance of a range of questioned substances including soils, drugs, explosives, currency, ivory and rhino horn has been widely documented. The present study wishes to highlight the applicability of IRMS and specifically stable carbon IRMS in determining the provenance of a carbonate rock that was switched for nickel metal exported from South Africa to Israel. The technique employed effectively argued against a South African origin for the rock whilst simultaneously supporting an Israeli origin, enabling investigators to focus their attention accordingly. The study represents the first documented instance known to the authors where IRMS has been employed in the forensic geo-location of a rock.     

析政治传播视角下的早间电视新闻节目

随道我国政治文化的逐渐发展,对于政治传播学的研究已越来越广泛,政治传播也已成为了我党宣传大政治方针,获取民意的一项重要手段。政治传播是与大众传播相依相伴的,不论是电视、报纸、广播、网络还是新媒体,都是政治传播的有效渠道,这里,我们主要探讨一下早间电视新闻节目的政治传播功能。