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61.
62.
Lotteries, the state fiscal gimmick of the eighties, operate in jurisdictions encompassing substantially more than half the nation's population and enjoy considerable public acceptance. The revenue they generate is small, rarely more than two percent of state general revenue, it is subject to major year-to-year swings, and it is very expensive to generate, particularly when vendor commissions are recognized as part of cost. Furthermore, lotteries bear a high implicit excise tax rate and, because of the pattern of play across income classes, appears to worsen the overall equity of the revenue system. Their economic impact appears to be that of an internal transfer, although states with major lottery equipment suppliers have most to gain, particularly if they do not operate their own lottery. Lotteries are not destined to become mainstays of government finance, although their spread is likely, even with the fiscal questions they raise.  相似文献   
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Reviews     
AIDS in Africa: The Social and Policy Impact edited by Norman Miller and Richard C. Rockwell Edwin Mellen Press, Lewiston (New York) and Queenston (Ontario), 1988. xxxi plus 336 pp. including map, tables, figures, notes, appendices and selected bibliographies. $110,00.

The Politics of Africa's Economic Stagnation by Richard Sandbrook Cambridge University Press, Cambridge, 1985. xiii plus 180 pp. including map, tables, notes and index. R.25,50 paperback.

Imperialism and Dependency: Obstacles to African Development by Daniel A. Offiong Howard University Press, Washington, DC, 1982. 304 pp. including tables, bibliography and index. $6,95 paperback.

Early Field Recordings: A Catalogue of Cylinder Collections at the Indiana University Archives of Traditional Music edited by Anthony Seeger and Louise S. Spear Indiana University Press, Bloomington, 1987. xviii plus 198 pp. $22,50.

Western Sahara: The Roots of a Desert War by Tony Hodges Lawrence Hill and Co., Westport (Connecticut), 1983. xii plus 388 pp. including maps, illustrations, tables, notes, appendix, bibliography and index. £6,95 paperback.

Somalia: Nation in Search of a State by David D. Laitin and Said S. Samatar Westview Press, Boulder (Colorado), and Gower, London, 1987. xvii plus 198 pp. including maps, illustrations, figures, tables, notes and index. $28,00.

Superpower Diplomacy in the Horn of Africa by Samuel M. Makinda Croom Helm, London and Sydney, 1987. 242 pp. including notes, appendices, select bibliography and index. £22,50.

Industrialization in West Africa by J.O.C. Onyemelukwe Croom Helm, London, 1984. v plus 226 pp. including tables, figures, bibliography and index. £17,95.

Modern Kongo Prophets: Religion in a Plural Society by Wyatt MacGaffey Indiana University Press, Bloomington, 1983. xiii plus 285 pp. including tables, figures, illustrations, notes, references and index. $12,00 paperback.

Naissance du Mozambique: Résistance et Révoltes Anticoloniales, 1854–1918 (Two Volumes) by René Pélissier Editions Pélissier, Orgeval (France), 1984. 833 pp. including maps, tables, notes, bibliography and index. $45,00 paperback.

The Political Economy of Namibia: An Annotated, Critical Bibliography by Tore LinnÉ Eriksen with Richard Moorsom Scandinavian Institute of African Studies, Uppsala, 1985. 423 pp. including map and authors’ index. SEK 110.

The Bureaucratic Struggle for Control of US Foreign Aid: Diplomacy versus Development in Southern Africa by Caleb Rossiter Bowker Publishing Co., Epping (England), and Westview Press, Boulder (Colorado), 1985. xiii plus 250 pp. including figures, tables, notes, bibliography and index. $25,50 paperback.

The Politics of Economic Power in Southern Africa by Ronald T. Libby Princeton University Press, Princeton (New Jersey), 1987. xxiii plus 361 pp. including maps, tables, bibliography and index. $45,00. $14,50 paperback.

South Africa in Crisis edited by Jesmond Blumenfeld Croom Helm, London, 1987. x plus 207 pp. including tables, notes and index. £19,95.

Pass Controls and the Urban African Proletariat in South Africa By Doug Hindson Ravan Press, Johannesburg, 1987. xii plus 121 pp. including notes, bibliography and index. R 14,00 paperback.

Hidden Struggles in Rural South Africa: Politics and Popular Movements in the Transkei and Eastern Cape, 1890–1930 by William Beinart and Colin Bundy Ravan Press, Johannesburg, 1987. xxvi plus 326 pp. including illustrations, maps, notes and index. R24,00 paperback.  相似文献   

65.
The Downstream Benefits of Experimentation   总被引:1,自引:0,他引:1  
The debate about the cost-effectiveness of randomized fieldexperimentation ignores one of the most important potentialuses of experimental data. This article defines and illustrates"downstream" experimental analysis—that is, analysis ofthe indirect effects of experimental interventions. We arguethat downstream analysis may be as valuable as conventionalanalysis, perhaps even more so in the case of laboratory experimentation.  相似文献   
66.
Assessment of the role of air bag deployment in injury causation in a crash of any severity requires analysis of occupant, vehicle, and impact data. The potential injurious role of an air bag is independent of crash severity and is more obvious in minor collisions, particularly those involving "out-of-position" occupants. Factors such as occupant height and other constitutional and medical factors, intoxication, age, type, and proper use of other restraint systems, pre-impact braking and multiple impacts can contribute to an occupant being "out-of-position." Two injury mechanisms are described in out-of-position occupants: "punch-out" when the individual covers the air bag module before deployment and "membrane-force" when the occupant contacts a partly deployed air bag. Each mechanism is associated with injury patterns. In adults, "punch-out" can cause thoraco-abdominal trauma and "membrane-force" loading can lead to craniocervical injury. This can also occur in short-statured occupants including children subjected to both types of loading. In more severe collisions, other factors, e.g., intrusion, steering column and seatbelt loading and other occupant compartment contacts, can contribute to trauma.  相似文献   
67.
A 2-month-old infant girl died suddenly as a result of torsion of the uterine adnexa. The infant was found unresponsive in bed and was pronounced dead shortly after her arrival at a hospital. There were no antecedent signs of illness. At autopsy, the right ovary and right fallopian tube were twisted and were dark purple, swollen, and necrotic. The right ovary was enlarged by a follicle cyst 4 cm in diameter, which likely precipitated the torsion. The mechanism of death was unclear but may have resulted from the release of cytokines produced in response to necrotic adnexal tissue. Fatal uterine adnexal torsion has been reported rarely in infants; in all those cases there were antecedent symptoms. Torsion of the uterine adnexa should be included in the differential diagnosis of sudden death in infancy.  相似文献   
68.
A sensitive analytical method was developed for quantitative analysis of delta(9)-tetrahydrocannabinol (delta(9)-THC), 11-nor-delta(9)-tetrahydrocannabinol-carboxylic acid (delta(9)-THC-COOH), cannabinol (CBN) and cannabidiol (CBD) in human hair. The identification of delta(9)-THC-COOH in hair would document Cannabis use more effectively than the detection of parent drug (delta(9)-THC) which might have come from environmental exposure. Ketamine was added to hair samples as internal standard for CBN and CBD. Ketoprofen was added to hair samples as internal standard for the other compounds. Samples were hydrolyzed with beta-glucuronidase/arylsulfatase for 2h at 40 degrees C. After cooling, samples were extracted with a liquid-liquid extraction procedure (with chloroform/isopropyl alcohol, after alkalinization, and n-hexane/ethyl acetate, after acidification), which was developed in our laboratory. The extracts were analysed before and after derivatization with pentafluoropropionic anhydride (PFPA) and pentafluoropropanol (PFPOH) using a Hewlett Packard gas chromatographer/mass spectrometer detector, in electron impact mode (GC/MS-EI). Derivatized delta(9)-THC-COOH was also analysed using a Hewlett Packard gas chromatographer/mass spectrometer detector, in negative ion chemical ionization mode (GC/MS-NCI) using methane as the reagent gas. Responses were linear ranging from 0.10 to 5.00 ng/mg hair for delta(9)-THC and CBN, 0.10-10.00 ng/mg hair for CBD, 0.01-5.00 ng/mg for delta(9)-THC-COOH (r(2)>0.99). The intra-assay precisions ranged from <0.01 to 12.40%. Extraction recoveries ranged from 80.9 to 104.0% for delta(9)-THC, 85.9-100.0% for delta(9)-THC-COOH, 76.7-95.8% for CBN and 71.0-94.0% for CBD. The analytical method was applied to 87 human hair samples, obtained from individuals who testified in court of having committed drug related crimes. Quantification of delta(9)-THC-COOH using GC/MS-NCI was found to be more convenient than GC/MS-EI. The latter may give rise to false negatives due to the detection limit.  相似文献   
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