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.     

The Downstream Benefits of Experimentation

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.     

Driver and front seat passenger fatalities associated with air bag deployment. Part 2: A review of injury patterns and investigative issues

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.     

Analysis of ionic ratios in myocardial tissue and their relation to cardiac damage

The authors evaluated the usefulness of the postmortem biochemical analysis of ionic ratios in different parts of the heart and their relation to cardiac damage caused by chest trauma, as observed by anatomopathologic study. Fifty-nine 59 cases were studied, selected from routine necropsies, and samples were taken from different sites of cardiac tissue. The cause of death was trauma in 40 cases and nontraumatic causes in 19 cases. The object of this study was to analyze the levels of Na+, K+, Ca+2, Mg+2, and Zn+2 in different zones of the heart, and the relationship between intracellular and extracellular ion ratios and the different causes of death and any anatomopathologic alterations observed. The biochemical tests revealed a possible relation between the ionic values and cause of death. Alterations in cell membrane permeability and corresponding modification of the ionic ratios were produced earlier than histologic alterations, which need longer to establish themselves whether or not they follow a traumatic process.     

Hair analysis for delta(9)-THC,delta(9)-THC-COOH,CBN and CBD,by GC/MS-EI. Comparison with GC/MS-NCI for delta(9)-THC-COOH

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.     

STR data for the AmpFlSTR Profiler Plus loci from Greece

Allele frequencies for the nine STRs included in the AmpFlSTR Profiler Plus kit (D3S1358, VWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317 and D7S820) were estimated from a sample of 143 unrelated individuals living in different regions of Greece.     

Testing a Model of Resistance to Peer Pressure Among Mexican-Origin Adolescents

This study examined the factors associated with resistance to peer pressure toward antisocial behaviors among a sample of Mexican-origin adolescents (n=564) living in a large Southwestern city in the U.S. A model examining the influence of generational status, emotional autonomy from parents, and self-esteem on resistance to peer pressure was tested independently for boys and girls. Gender differences emerged in the factors that influenced resistance to peer pressure. Results indicated that resistance to peer pressure was influenced by generational status and emotional autonomy from parents for both boys and girls. However, self-esteem was found to influence resistance to peer pressure only for boys.Mayra Y. Bámaca is a graduate student in Family and Human Development at Arizona State University. Her research interests include adolescent development among ethnically diverse populations, the influence of contextual factors in development, parenting adolescents, and resiliency among Latino adolescents and their families. This work was based on the master’s thesis of the first author.Adriana J. Uma?a-Taylor received her Ph.D. from the University of Missouri-Columbia and is currently an Assistant Professor of Family and Human Development at Arizona State University. Her research interests include ethnic identity formation during adolescence and resilience among Latino adolescents and their families.This study was supported, in part, by a grant to the second author from the Fahs Beck Fund for Research and Experimentation of the New York Community Trust.     

Policy Gatekeepers in Latin American Legislatures

Legislators who control the congressional agenda have a significant advantage over the membership at large. Policy gatekeepers can restrict change to outcomes they prefer over the status quo and can use this prerogative to keep a legislative party or coalition unified. This article examines agenda-setting rules in 26 Latin American chambers, shows why the institutional structure is theoretically relevant, and reveals some implications for policymaking with evidence from Argentina, Chile, and Mexico. Majority leaders in the Argentine and Chilean lower chambers have successfully blocked passage of legislation opposed by most of their fellow partisans despite the lack of codified gatekeeping rights. Since 1997, none of the major Mexican parties has benefited from the gatekeeping rights established in the rules. Instead, the benefits have come from the parties' advantageous position with respect to the other parties on the steering committee setting the plenary agenda.