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41.
The concept 'community' is underspecified in the political theory literature — it must have a more specific reference than just some collectivity or some network of social relations. But attempts to specify what is specific about the relation of community are unsatisfactory. And references to 'actual physical' communities overlook the symbolic and imagined aspects of community, which furthermore destabilise putative communities as much as they stabilise them. Analysis of social relations and networks, and theories of what patterns of relations are conducive to human flourishing should deploy more precise sociological categories. 相似文献
42.
Melvin L. De Fleur 《Society》1988,25(2):72-81
His many publications include Theories of Mass Communication; Understanding Mass Communication; Milestones in Mass Communication Research;and, with Otto N. Larsen, The Flow of Information. 相似文献
43.
44.
Samyn N De Boeck G Wood M Lamers CT De Waard D Brookhuis KA Verstraete AG Riedel WJ 《Forensic science international》2002,128(1-2):90-97
In a double-blind placebo controlled study on psychomotor skills important for car driving (Study 1), a 75 mg dose of +/- 3,4-methylenedioxymethamphetamine (MDMA) was administered orally to 12 healthy volunteers who were known to be recreational MDMA-users. Toxicokinetic data were gathered by analysis of blood, urine, oral fluid and sweat wipes collected during the first 5h after administration. Resultant plasma concentrations varied from 21 to 295 ng/ml, with an average peak concentration of 178 ng/ml observed between 2 and 4h after administration. MDA concentrations never exceeded 20 ng/ml. Corresponding MDMA concentrations in oral fluid, as measured with a specific LC-MS/MS method (which required only 50 microl of oral fluid), generally exceeded those in plasma and peaked at an average concentration of 1215 ng/ml. A substantial intra- and inter-subject variability was observed with this matrix, and values ranged from 50 to 6982 ng/ml MDMA. Somewhat surprisingly, even 4-5h after ingestion, the MDMA levels in sweat only averaged 25 ng/wipe. In addition to this controlled study, data were collected from 19 MDMA-users who participated in a driving simulator study (Study 2), comparing sober non-drug conditions with MDMA-only and multiple drug use conditions. In this particular study, urine samples were used for general drug screening and oral fluid was collected as an alternative to blood sampling. Analysis of oral fluid samples by LC-MS/MS revealed an average MDMA/MDEA concentration of 1121 ng/ml in the MDMA-only condition, with large inter-subject variability. This was also the case in the multiple drug condition, where generally, significantly higher concentrations of MDMA, MDEA and/or amphetamine were detected in the oral fluid samples. Urine screening revealed the presence of combinations such as MDMA, MDEA, amph, cannabis, cocaine, LSD and psilocine in the multiple-drug condition. 相似文献
45.
Everyone likes a winner: An empirical test of the effect of electoral closeness on turnout in a context of expressive voting 总被引:1,自引:0,他引:1
Under instrumental voting closer elections are expected to have higher turnout. Under expressive voting, however, turnout may increase with decreasing closeness when voters have a preference for winners. An empirical test using data on Belgian municipal elections supports this. We find that turnout reaches a local maximum when the largest party in the election obtains just over 52% of the seats and then falls (supporting the “instrumental” closeness-argument). There is, however, another turning point: the presence of a highly dominating party (receiving at least two-thirds of the votes) stimulates turnout despite the fact that dominance implies lower closeness. 相似文献
46.
47.
Clauwaert KM Van Bocxlaer JF Lambert WE De Leenheer AP 《Forensic science international》2000,110(3):157-166
Hair samples of eight postmortem cases were analyzed in segments of 1 to 3 cm for cocaine, benzoylecgonine and cocaethylene. Samples were prepared for analysis by digestion in 0.1 M HCl and subsequent extraction with mixed-mode solid-phase extraction columns. Measurement was made by reversed-phase, narrow-bore HPLC and fluorescence detection using two laboratory-made internal standards. The concentrations were in the region of 0.29-316 ng/mg of hair for cocaine, 0.43-141 ng/mg of hair for benzoylecgonine and 0.93-1.83 ng/mg of hair for cocaethylene. All eight investigated cases had cocaine-positive segments. In six of the cases, all segments were positive, suggesting regular cocaine use and two showed in-between negative segments indicating an interruption or a change of the abuse intensity. The results showed a second, remarkable observation, i.e. enormous concentration differences (factor >150) for both cocaine and benzoylecgonine between the different subjects. Furthermore, interindividual cocaine/benzoylecgonine ratios ranged from 0.02 to 8.43. We believe these observations could in part be attributed to both some of the still existing limitations in the analytical approach(es), especially the mandatory hair washing steps, and in our still too limited knowledge of the hair incorporation processes. Nevertheless, in some cases, segmental analysis proved to be an important tool to distinguish, together with postmortem examination, deadly chronic abuse from single acute drug overdosage. 相似文献
48.
ABSTRACTFactories remain significant sites of employment, crucial to capitalism. In the twentieth century, scholars registered achievements in documenting their history, but since the late 1980s, and for a generation, the field lost impetus within labour history although insights continued to accumulate through work in adjacent disciplines. The factory has not featured on the agenda of ‘transnational’ and ‘global’ labour history, but we suggest that it can and should contribute to that broader global project, reinvigorating labour history, not least by contributing a dimension close to workers’ everyday experience. 相似文献
49.
Three-dimensional cranio-facial reconstruction in forensic identification: latest progress and new tendencies in the 21st century 总被引:3,自引:0,他引:3
Three-dimensional (3D) cranio-facial reconstruction can be useful in the identification of an unknown body. The progress in computer science and the improvement of medical imaging technologies during recent years had significant repercussions on this domain. New facial soft tissue depth data for children and adults have been obtained using ultrasound, CT-scans and radiographies. New guidelines for facial feature properties such as nose projection, eye protrusion or mouth width, have been suggested, but also older theories and "rules of thumbs" have been critically evaluated based on digital technology. New fast, flexible and objective 3D reconstruction computer programs are in full development. The research on craniofacial reconstruction since the beginning of the 21st century is presented, highlighting computer-aided 3D facial reconstruction. Employing the newer technologies and permanently evaluating and (re)questioning the obtained results will hopefully lead to more accurate reconstructions. 相似文献
50.
De Greef S Claes P Mollemans W Loubele M Vandermeulen D Suetens P Willems G 《Journal of forensic sciences》2005,50(6):1282-1288
A mobile and fast, semi-automatic ultrasound (US) system was developed for facial soft tissue depth registration. The system consists of an A-Scan ultrasound device connected to a portable PC with interfacing and controlling software. For 52 cephalometric landmarks, the system was tested for repeatability and accuracy by evaluating intra-observer agreement and comparing ultrasound and CT-scan results on 12 subjects planned for craniofacial surgery, respectively. A paired t-test evaluating repeatability of the ultrasound measurements showed 5.7% (n = 3) of the landmarks being significantly different (p < 0.01). US and CT-scan results showed significant differences (p < 0.01) using a Wilcoxon signed rank test analysis for 11.5% (n = 6) of the landmarks. This is attributed to a difference in the volunteer's head position between lying (CT) and sitting (US). Based on these tests, we conclude that the proposed registration system and measurement protocol allows relatively fast (52 landmarks/20 min), non-invasive, repeatable and accurate acquisition of facial soft tissue depth measurements. 相似文献