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The shift from natural to controlled fertility: a cross-sectional analysis of ten Indian states.

This study investigates the causes of the transition from natural to controlled fertility in India by comparing couples who have ever used contraception with those who remained under natural fertility conditions. Using sample study data this paper considers the relative effects of the factors involved in the shift to controlled fertility among ten early-transitional Indian States in 1970. The results indicate that it is primarily improvements in child mortality and its effects through intervening factors that account for the transition. The implication is that the success of a family planning program is largely a function of improvements in child health.

Child, Preschool↗

A survey of attitudes concerning contraception and the resolution of teenage pregnancy.

This study reports the results of a survey of 498 respondents in a large midwestern community concerning their attitudes toward making contraceptive services available to teenagers and the manner in which a teenage pregnancy should be resolved. The results indicated that the large majority of respondents approved of the practice of making contraceptives available to teenagers but there were also significant differences in attitudes expressed which were dependent upon demographic characteristics of the respondent. There was also considerable variability in the attitudes expressed concerning the resolution of a teenage pregnancy. The preferred method of resolution depended again on the demographic characteristics of the respondent. Keeping the baby and placing the baby for adoption were the most frequent choices. These results are discussed with relation to the present strong political conservative movement in the nation.

Abortion, Induced↗

A dynamic phantom for radionuclide renography.

The aim of the study was to develop and test a dynamic phantom simulating radionuclide renography. The phantom consisted of five partly lead covered plastic containers simulating kidneys, heart, bladder and background (soft tissues, liver and spleen). Dynamics were performed with multiple movable steel plates between containers and a gamma camera. Control of the plates is performed manually with a stopwatch following exact time schedules. The containers were filled with activities (99mTc) which produce count rates close to clinical situations. Count rates produced by the phantom were compared with ten clinical renography cases: five 99mTc MAG3 and five 99mTc DTPA examinations. Two phantom simulations were repeated three times with separate fillings, acquisitions and analyses. Precision errors as a coefficient of variation (CV) of repeated measurements were calculated and theoretical values were compared with the corresponding measured ones. A multicentre comparison was made between 19 nuclear medicine laboratories and three clinical cases were simulated with the phantom. Correlations between count rates produced by the phantom and clinical studies were r = 0.964 for 99mTc MAG3 (p < 0.001) and 0.961 for 99mTc DTPA (p < 0.001). The precision error was 4.5 +/- 3.2% and the percentage difference between theoretical and measured values for Tmax was 4.0 +/- 1.6%. Images and curves of the scanned phantom were close to a real patient in all 19 laboratories but calculated parameters varied: the difference between theoretical and measured values for Tmax was 6.8 +/- 6.2%. The difference between laboratories is most probably due to variations in acquisition protocols and analysis programs: 19 laboratories with 18 different protocols and 8 different programs. The dynamics were found to be repeatable and suitable for calibration purposes for radionuclide renography programs and protocols as well as for multicentre comparisons.

Finland↗

Demography of the Juang tribal population of Orissa.

Demographic analysis of genealogical data collected in 1954 for 23 Juang villages was undertaken employing indirect estimation techniques and computer projection methodology. Results indicated that this group did not feature the historically high fertility levels associated with Indian tribal groups, although fertility was higher than previously reported for the Juang. The population did feature a mortality differential, with worse mortality conditions than the Indian national population at this time. Reversed sexual mortality differentials, common in South Asian populations, were also present for the Juang. Computer projection investigation revealed a steadily growing population, in contrast to some Indian tribal groups faced with extinction.

Adolescent↗

Recent changes in the sociodemographic profile of sterilization acceptors in Nepal.

The records of 8056 Nepalese males and 9291 females sterilized from 1979-1983 were analyzed. Compared with data from previous studies (1970-1976), significant decreases occurred in the average age of female acceptors (30.6 vs. 33.1, P less than 0.01) and wives of male acceptors (28.4 vs. 31.7, P less than 0.01). Also, the average number of living children per couple decreased by one child (4.9-3.9, P less than 0.01) for male acceptors and 0.6 (4.8-4.2, P less than 0.01) for female acceptors. Finally in 83.2% of the cases, the operation was performed within 3 years of the last delivery.

Adult↗

Evaluating the impact of a theory-based sexuality and contraceptive education program.

A controlled field study involving 1,444 adolescent males and females 13-19 years of age was performed to compare a sexuality education program based on the health belief model and social learning theory with several publicly funded community-based and school-based interventions. Among males who had never had intercourse prior to participating in the study, those in the experimental program were more likely than those in the comparison programs to maintain abstinence over the next year; there was no program effect, however, among females. Among female adolescents who initiated intercourse after the start of the study, attendees of the comparison programs were more likely to have used an effective contraceptive at most recent intercourse and to have used an effective method more consistently than were those who attended the experimental program; no such association was seen among comparable young men. Both experimental and comparison programs significantly increased the consistent use of effective methods among teenagers who had been coitally active before attending the programs. Among males, however, when preintervention contraceptive efficiency was held constant, the experimental program led to significantly greater contraceptive efficiency during the follow-up year than did the comparison programs; among females, the two approaches produced an equivalent degree of improvement. Finally, prior exposure to sexuality education was associated with greater contraceptive efficiency at the one-year follow-up among almost all sexual-experience and gender groups, regardless of the type of intervention program attended.

Adolescent↗

Ethnic differences in contraceptive use in Sri Lanka.

In Sri Lanka in 1975, the majority Sinhalese had a much higher use of contraception than either the Sri Lanka Tamils or the Moors. This study uses a national sample of women of childbearing age gathered by the Sri Lanka World Fertility Survey in 1975 to assess four possible reasons for differential contraceptive use: (1) differences in socioeconomic position; (2) cultural differences; (3) minority status; and (4) differential access to family planning services. The first three explanations focus on differences in the demand for contraception while the fourth explanation focuses on differences in the availability of contraceptives. The socioeconomic, cultural, and minority status hypotheses fail to explain the higher contraceptive use among the Sinhalese. The evidence is consistent with the idea that ethnic differences in contraceptive use were largely caused by differential access to family planning services.

Adult↗

Prosocial effects of entertainment television in India.

The study examines the prosocial effects of Hum Log (We People), India's 1st long running television soap opera. Hum Log was a prosocial TV program that was designed to promote women's status in Indian society. Regression analysis was used to measure the degree to which exposure to Hum Log affected viewers' (1) awareness of certain prosocial beliefs promoted by the series, (2) level of TV dependency, (3) involvement with the characters of Hum Log, and (4) adherence to 3 prosocial beliefs promoted by Hum Log. Exposure to Hum Log was positively associated with viewer's awareness of the program's prosocial messages, TV dependency, and involvement with TV characters in the series. Viewers who were more exposed to Hum Log were also more likely to believe in women's equality and women's freedom of choice, but not in family planning. The implications of these findings are discussed in terms of present and future research on the use of prosocial TV programs for development in Asia.

Advertising↗

High performance computing in biology: multimillion atom simulations of nanoscale systems.

Computational methods have been used in biology for sequence analysis (bioinformatics), all-atom simulation (molecular dynamics and quantum calculations), and more recently for modeling biological networks (systems biology). Of these three techniques, all-atom simulation is currently the most computationally demanding, in terms of compute load, communication speed, and memory load. Breakthroughs in electrostatic force calculation and dynamic load balancing have enabled molecular dynamics simulations of large biomolecular complexes. Here, we report simulation results for the ribosome, using approximately 2.64 million atoms, the largest all-atom biomolecular simulation published to date. Several other nano-scale systems with different numbers of atoms were studied to measure the performance of the NAMD molecular dynamics simulation program on the Los Alamos National Laboratory Q Machine. We demonstrate that multimillion atom systems represent a 'sweet spot' for the NAMD code on large supercomputers. NAMD displays an unprecedented 85% parallel scaling efficiency for the ribosome system on 1024 CPUs. We also review recent targeted molecular dynamics simulations of the ribosome that prove useful for studying conformational changes of this large biomolecular complex in atomic detail.

Computational Biology↗

CONV--convolution for responses to a finite diameter photon beam incident on multi-layered tissues.

A convolution program (CONV) solving responses to a collimated finite diameter photon beam perpendicularly incident on a multi-layered tissue has been coded in ANSI Standard C, hence, the program can be executed on various computers. The program, employing an extended trapezoidal rule for integration, convolves the responses to an infinitely narrow photon beam computed by a companion program (MCML). Dynamic data allocation is used for CONV as well as MCML, therefore, the number of tissue layers and grid elements of the grid system can be varied at run time. The potential error due to not scoring the first photon-tissue interactions separately is illustrated. The program, including the source code, has been in the public domain since 1992 and can be downloaded from the web site at http:(/)/biomed.tamu.edu/-lw.

Computer Simulation↗

The correlation between family planning program inputs and contraceptive use in Indonesia.

Using 1980 Census and 1986 service statistics program inputs, this paper evaluates the net correlation of socioeconomic, region, and program variables with 1987 contraceptive prevalence and method-specific use rates for Indonesian regencies and municipalities. The region variables--primarily, though not exclusively, reflecting program design and maturity--correlate most strongly with the contraceptive prevalence rates. Field-worker activities, field-worker supervisor activities, and community-based distributors also have a correlation with these rates. Pill use is highest in the areas that are predominantly Islamic and least developed, whereas the pattern is reversed for use of the IUD, condom, and other modern methods (mainly female sterilization). The findings are assessed in terms of their implications for policymaking.

Community Health Services↗