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Mortality pattern in the Emergency Paediatric Unit of Ahmadu Bello University Teaching Hospital, Zaria, Nigeria.

Three hundred and seven (307) deaths were recorded out of 3,155 admissions into the Emergency Paediatric Unit of Ahmadu Bello University Teaching Hospital Zaria between January 1st and December 31st 1986, giving a percentage mortality of 9.9 percent. 67 percent of the patients who died were aged between one month and twenty four months, and the overall male: female ratio of deaths was 1:1.04. Measles with complications was the commonest cause of death (24.1 percent) closely followed by protein energy malnutrition (23 percent) and respiratory tract infection (18 percent). Over half of the patients (57.6 percent) died less than 24 hours after admission. As most deaths resulted from preventable conditions, the implications of this finding, and suggestions on how to improve the situation are discussed.

Cause of Death↗

The importance of root gravitropism for inter-root competition and phosphorus acquisition efficiency: results from a geometric simulation model.

We have observed that low soil phosphorus availability alters the gravitropic response of basal roots in common bean (Phaseolus vulgaris L.), resulting in a shallower root system. In this study we use a geometric model to test the hypotheses that a shallower root system is a positive adaptive response to low soil P availability by (1) concentrating root foraging in surface soil horizons, which generally have the highest P availability, and (2) reducing spatial competition for P among roots of the same plant. The growth of nine root systems contrasting in gravitropic response over 320 h was simulated in SimRoot, a dynamic three-dimensional geometric model of root growth and architecture. Phosphorus acquisition and inter-root competition were estimated with Depzone, a program that dynamically models nutrient diffusion to roots. Shallower root systems had greater P acquisition per unit carbon cost than deeper root systems, especially in older root systems. This was due to greater inter-root competition in deeper root systems, as measured by the volume of overlapping P depletion zones. Inter-root competition for P was a significant fraction of total soil P depletion, and increased with increasing values of the P diffusion coefficient (De), with root age, and with increasing root gravitropism. In heterogenous soil having greater P availability in surface horizons, shallower root systems had greater P acquisition than deeper root systems, because of less inter-root competition as well as increased root foraging in the topsoil. Root P acquisition predicted by SimRoot was validated against values for bean P uptake in the field, with an r2 between observed and predicted values of 0.75. Our results support the hypothesis that altered gravitropic sensitivity in P-stressed roots, resulting in a shallower root system, is a positive adaptive response to low P availability by reducing inter-root competition within the same plant and by concentrating root activity in soil domains with the greatest P availability.

Computer Simulation↗

Program evaluation. Part 2: A responsive model proposal.

While program evaluation is necessary for understanding and improving educational programs in nursing, it is frequently surrounded by a climate of unease and perplexity. The first article (September/October 1990) in this two-part series reviewed models of program evaluation. This second article examines the state-of-the-art of program evaluation in nursing education and proposes implementation of a responsive model of evaluation in schools of nursing. The series aims to foster more dynamic, efficient program analysis, thereby enhancing the effectiveness of nursing education programs.

Education, Nursing↗

Do family planning programs affect fertility preferences? A literature review.

A literature review finds few studies about whether family planning programs have reduced fertility preferences. The strong and surprising evidence from Matlab, Bangladesh, demonstrated that this intensive program did not decrease preferences; however, it did crystallize latent demand for fewer children, resulting in a demand for contraception. One cross-national multivariate study was consistent with this finding. A few intracountry multivariate studies found small program effects, decreasing the number of children that couples want. An intensive multimethod study in India found plausible larger effects. Most studies of program media effects are flawed by possible selection bias, but one longitudinal study avoids this pitfall and finds large effects for one country. Program feedback effects are plausible but not yet demonstrated empirically. The effects of a coercive program are plausible, at least in China, but not definitively demonstrated. Several promising unpublished studies may strengthen the case for program effects in reducing fertility preferences, now often based on plausible but not conclusive evidence. Stronger generalizations require better studies of a wider range of locations.

Choice Behavior↗

Vision, visual needs, and quality of life of older people in rural environments: a report and synthesis of a meeting.

Vision as an aspect of rural aging was a major portion of the First International Conference on Rural Aging. Various perspectives on the relationship of vision to rural aging were presented in two symposia, two paper sessions, one workshop and the poster session (a total of 28 presentations). In summarizing this rich and varied material, the author emphasizes that: (a) vision is important to maintaining a healthy, active life as one ages; (b) impaired vision is generally preventable or treatable; (c) well-designed community programs can assist in prevention and treatment; and (d) assessing the effects of these programs requires evaluation of patients' quality of life. More research is needed to refine strategies for creating, maintaining and evaluating community-based eye care programs and integrating them with existing public health or other community programs.

Aged↗

Health of the nation: way forward in sexual health.

Sexual health is a wide concept encompassing education, health promotion and disease prevention, diagnosis and management of sexually transmitted diseases, screening and counselling for HIV antibodies, management of HIV infected patients, family planning, termination of pregnancy, psychosexual counselling, prevention of cervical and lower genital tract cancers, and sexual abuse. Implementation of The Health of the Nation (1992) will include assessing the current situation, views, alliances and interventions, need for research and development and within alliances setting challenging but achievable targets. The Health of the Nation includes a target for gonorrhoea which is a surrogate for partner change, sexually transmitted diseases in general and HIV infection, and a target for conceptions among those under 16 years of age. These targets need to be adjusted locally and may be staged. All interventions to achieve these targets must be available. Implementation of The Health of the Nation to achieve the main objectives which are to reduce the incidence of HIV infection and other sexually transmitted diseases as well as reducing the number of unwanted pregnancies and provision of effective family planning services will be challenging but sexual health gain will be well worthwhile.

Family Planning Services↗

Recovery of hidden information through synaptic dynamics.

The role of synaptic dynamics in processing neural information is investigated in a neural information channel with realistic model neurons having chaotic intrinsic dynamics. Our neuron models are realized in simple analogue circuits, and our synaptic connections are realized both in analogue circuits and through a dynamic clamp program. The information which is input to the first chaotic neuron in the channel emerges partially absent and partially 'hidden'. Part is absent because of the dynamical effects of the chaotic oscillation that effectively acts as a noisy channel. The 'hidden' part is recoverable. We show that synaptic parameters, most significantly receptor binding time constants, can be tuned to enhance the information transmission by the combination of a neuron plus a synapse. We discuss how the dynamics of the synapse can be used to recover 'hidden' information using average mutual information as a measure of the quality of information transport.

Animals↗

The impact of the Postponing Sexual Involvement curriculum among youths in California.

Postponing Sexual Involvement (PSI) is a widely implemented middle school curriculum designed to delay the onset of sexual intercourse. In an evaluation of its effectiveness among seventh and eighth graders in California, 10,600 youths from schools and community-based organizations statewide were recruited and participated in randomly assigned intervention or control groups; the curriculum was implemented by either adult or youth leaders. Survey data were collected before the program was implemented, and at three months and 17 months afterward. At three months, small but statistically significant changes were found in fewer than half of the measured attitudes, behaviors and intentions related to sexual activity; at 17 months, none of these significant positive effects of the PSI program had been sustained. At neither follow-up were there significant positive changes in sexual behavior; Youths in treatment and control groups were equally likely to have become sexually active, and youths in treatment groups were not less likely than youths in control groups to report a pregnancy or a sexually transmitted infection. The evaluation suggests that PSI may be too modest in length and scope to have an impact on youths' sexual behavior.

Adolescent↗

Education Now and Babies Later (ENABL): life history of a campaign to Postpone Sexual Involvement.

Education Now and Babies Later (ENABL), a statewide adolescent pregnancy prevention initiative, was inaugurated in California in June 1992. Developed by the state's Office of Family Planning, ENABL utilized a five-session intervention curriculum, Postponing Sexual Involvement (PSI), targeted at delaying the onset of sexual activity among youths aged 12-14. Schoolwide and community-based activities, along with a statewide media and public relations campaign, reinforced the intervention's message. Data collected from nearly 9,000 surveys, 75 individual interviews and 50 focus groups indicated that youths, parents and community representatives supported the initiative and endorsed its message, although most recommended changes to the curriculum. However, because no impact on sexual behavior could be demonstrated, the campaign was abruptly terminated in February 1996, despite recommendations that the program be retained and improved.

Adolescent↗

Innovative collaboration to prevent repeated adolescent pregnancies.

Nurse educators from a university setting and staff from the county health department collaborated to establish an innovative program to prevent repeated pregnancy in adolescents. Called Dollar-A-Day and patterned after the original in Denver, CO, the program was operated jointly for 5 years and today continues to operate under the auspices of the health department. Success of the venture is attributed to use of skills in assessment, building, managing, and evaluating, as described by Loxley (1997). These elements were used to construct a context for collaboration.

Adolescent↗

Viral genome organizer: a system for analyzing complete viral genomes.

The viral genome organizer (VGO) is designed to simplify the characterization and annotation of complete viral genomes (particularly those of large poxviruses) and to help researchers discover new genes and detect gene fragmentation. VGO is based on Genotator [Harris, N.L., 1997. Genome Res. 7, 754-762], an annotation workbench designed for the analysis of eukaryotic genomic sequences. VGO automates a number of database search routines (FASTA, BLASTP, PSI-BLAST and TBLASTN), processes the results through a multiple-alignment viewer (MView; [Brown, N.P., Leroy, C., Sander, C. , 1998. Bioinformatics 14, 380-381]) and serves to manage the hundreds of DNA, protein and database search results files that must be organized when dealing with large complete poxviral genomes. It also directs the generation a self-dotplot of the genome by Dotter [Sonnhammer, E.L.L., Durbin, R., 1995. A dot-matrix program with dynamic threshold control suited for genomic DNA and protein sequence analysis. Gene 167: GC1-10. http://www.sanger.ac. uk/Software/Dotter/] to uncover repeated genes and sequences and provides Internet links to programs for generation of restriction maps and analysis of potential PCR primers. The user-friendly graphical interface displays DNA and protein sequences, links to search results, ORFs, stop-start codons, restriction sites and flags of database searches. Currently, VGO and associated programs run in an X-windows environment on commonly available UNIX machines.

Databases, Factual↗

Fertility reduction and the quality of family planning services.

The purpose of this paper is to determine whether a focus on quality of family planning services is consistent with meeting demographic objectives. An analytical framework that links the six elements of quality with fertility is described. A review of existing literature and analysis suggest that improvements in quality of family planning services by enhancing the choice of contraceptive methods available in a country would increase the overall practice of contraception and thus would result in fertility reduction.

Contraception↗

Sex education and family planning services for young adults: alternative urban strategies in Mexico.

In Mexico, youth face difficulties in obtaining reliable information on sex education and family planning through existing community programs. Two alternative strategies to provide these services are being tested in poor urban areas of Monterrey. In one experimental area, Integrated Youth Centers were established, which provide sex education and family planning services as well as counseling, academic tutoring, and recreational activities. In another area, trained young adults and community counselors work through informal networks to provide sex education and family planning information. Both utilization and the cost of these services are examined in the context of plans for expanding coverage in Mexico-U.S. border areas.

Adolescent↗