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71.
Robert M. Bond Jaime E. Settle Christopher J. Fariss Jason J. Jones James H. Fowler 《政治交往》2017,34(2):261-281
Which individuals are most responsive to get-out-the-vote (GOTV) messages that emphasize the social aspects of voting? Recent literature has shown that GOTV messages that emphasize the social environment in which an individual is embedded are particularly effective at increasing voting rates. Until now, we have not had good estimates for the types of people for whom social GOTV messages are most effective. We report a new set of disaggregated results of a randomized controlled trial of political mobilization messages delivered to 61 million Facebook users during the 2010 U.S. Congressional elections. The results suggest that social endorsement cues are differentially effective for different types of political behaviors—political expression, information seeking, and voting—and for different kinds of people, based on both demographic and social characteristics, raising new questions about the mechanisms explaining social pressure effects. 相似文献
72.
For 50 years after World War II, Latvia was incorporated into the former Soviet Union. Although in theory the use of regional languages was not discouraged, in practice knowledge of Russian was obligatory. Since restoration of the country’s independence in 1991, Latvian has again become the official language, and knowledge of Russian is widespread but optional. These political events have created a natural experiment in the possible effects of almost universal bilingualism on a language. In this study, we examine the phonetic characteristics of the Latvian syllable intonations across generations. Native speakers of Latvian, ranging from retirement age to teens, were recorded reading a word list, sentences, and a short narrative. We find that younger speakers who used Latvian only about half of the time showed fading in their pronunciation of the intonations. 相似文献
73.
The effect of electrostatic fingerprint visualization on integrated ballistic identification systems
Visualization of fingerprint corrosion on spent brass cartridge cases by the application of a high electrical potential and conducting carbon powder is becoming an accepted method of fingerprint enhancement. However, to date, no examination has been made of any effect this technique has on ballistic identification. To resolve this, images of the breech face and firing pin marks were captured on six plated nickel and six brass primer cup spent cartridge cases. Three nickel and three brass cases were then subjected to the application of a potential of +2500 V for a period of 1 min. The remaining cases were additionally subjected to the application of carbon powder. These latter cases were then washed to remove all traces of powder. Each case was recaptured with the same ballistic identification apparatus and imaging procedure. None of the twelve cases showed any visual difference after the application of the potential or conducting powder. 相似文献
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75.
Lisa Reid B.Sc. Kal Chana C.Chem. John W. Bond D.Phil. Matthew J. Almond Ph.D. Stuart Black Ph.D. 《Journal of forensic sciences》2010,55(3):753-756
Abstract: The collection efficiency of two widely used gunshot residue (GSR) collection techniques—carbon‐coated adhesive stubs and alcohol swabs—has been compared by counting the number of characteristic GSR particles collected from the firing hand of a shooter after firing one round. Samples were analyzed with both scanning electron microscopy and energy dispersive X‐rays by an experienced GSR analyst, and the number of particles on each sample containing Pb, Ba, and Sb counted. The adhesive stubs showed a greater collection efficiency as all 24 samples gave positive results for GSR particles whereas the swabs gave only positive results for half of the 24 samples. Results showed a statistically significant collection efficiency for the stub collection method and likely reasons for this are considered. 相似文献
76.
This paper examines how the legal design of a leasing arrangementaffects the value of the leased asset. The model focuses onthe incentive problems that arise when the ownership and useof an asset are separated. The results suggest that an efficientlydesigned lease may involve elements of property law, contractlaw, or both. This conclusion helps explain why the law of leaseshas historically occupied the nexus between these two areasof the common law. 相似文献
77.
Abstract: Latent fingerprint visualization on discharged shell casings can provide good forensic evidence, particularly if the casing is recovered at the scene of a crime where a firearm has been discharged. Unfortunately, visualization of such latent fingerprints when they were deposited prior to discharge of the firearm is problematic as both increased temperature and abrasive friction can inhibit fingerprint visualization with conventional techniques. We present a case study that demonstrates latent fingerprint visualization on a discharged shell casing recovered 14 years ago from the scene of a homicide. Previous cyanoacrylate fuming of the casing had failed to reveal any fingerprints. We use a visualization technique in which a conducting carbon powder adheres preferentially to latent fingerprint corrosion of the casing surface, following the application of a potential of 2.5 kV to the casing. This technique presents opportunities for the review of old cases and for consideration of its use in current cases. 相似文献
78.
Fingerprint sweat from 40 donors was deposited onto samples of five α and α + β phase brasses, comprising five alloys with different copper and zinc concentrations, two of which also had the addition of small concentrations of lead. Visual grading of the visibility of the corrosion revealed that brasses with the least amount of zinc produced the most visible and fully formed fingerprints from the most donors. Consideration of previously reported mechanisms for the corrosion of brass suggests red copper (I) oxide as a likely corrosion product for low zinc brasses, and a consideration of the color, composition, and solubility of fingerprint sweat corrosion products suggests that copper (I) oxide produces good contrast and visibility with the brass substrate. Scanning electron microscope images of the corrosion of all five alloys confirmed the enhanced contrast between corroded and uncorroded areas for low zinc alloys. 相似文献
79.
Pipe bombs made from 1 mm thick copper pipe were detonated with a low explosive power powder. Analysis of the physical characteristics of fragments revealed that the copper had undergone work hardening with an increased Vickers Hardness of 107HV1 compared with 80HV1 for unexploded copper pipe. Mean plastic strain prior to fracture was calculated at 0.28 showing evidence of both plastic deformation and wall thinning. An examination of the external surface showed microfractures running parallel with the length of the pipe at approximately 100 μm intervals and 1–2 μm in width. Many larger fragments had folded “inside out” making the original outside surface inaccessible and difficult to fold back through work hardening. A visual examination for fingerprint corrosion revealed ridge details on several fragments that were enhanced by selective digital mapping of colors reflected from the surface of the copper. One of these fingerprints was identified partially to the original donor. 相似文献
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Emily Sonnex Ph.D. Matthew J. Almond D.Phil. John W. Bond O.B.E. D.Phil. 《Journal of forensic sciences》2016,61(4):1100-1106
A method has been developed for the visualization of latent fingerprints on fabrics, which is based upon cyanoacrylate (superglue) fuming followed by imaging using an infrared microscope. Results show that imaging on smooth, shiny fabrics such as polyester, silk, nylon, and acetate of different colors and patterns can give an improvement over existing enhancement methods. Results for cotton and polycotton were less successful and it is thought this may be due a combination of the presence of the carbonyl functional group in these fabrics as well as their absorbency to fingerprint sweat. The carbonyl peak (1700 cm?1) provided the optimum spectroscopic feature to map and image a fingerprint. Comparisons between infrared mapping at a specific frequency range and principal component analysis showed that improved imaging was obtained with principal component analysis. 相似文献