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At least 199 records · Page 11Linked to original sources
PubMed1985

Population trends of Soviet cities, 1970-84.

This article contains a time series for the population of cities of the Soviet Union for the period 1970-1984. The data are from the Soviet censuses of 1970 and 1979 and from official estimates for 1974 and 1984. The article is designed as a continuation of an earlier time series developed by Chauncy D. Harris for the period 1897-1967. "The updated material consists of a series of tables following the patterns of the earlier material, a methodological explanation, and a discussion of significant trends in the population size of Soviet cities."

Demography↗
PubMed1997

Maternal mortality in rural Zambia.

OBJECTIVE: To assess maternal mortality. DESIGN: Sisterhood method survey and hospital data. SETTING: Communities in Kalabo District, a very remote rural area in western Zambia; Kalabo District Hospital. RESULTS: The number of respondents in the sisterhood method survey was 1,978. The estimated maternal mortality ratio derived from this survey was 1,238 per 100,000 live births. The hospital study involved 2,474 deliveries of 2,374 live babies. The official number of maternal deaths was 13. Further investigation of files revealed an additional 15 maternal deaths, bringing the institutional maternal mortality rate from 548 to 1,179 per 100,000 live births. The major causes of direct maternal deaths were obstructed labor and sepsis. In 71% of all cases substandard care factors contributed. CONCLUSIONS: Maternal mortality in rural Zambia is among the highest as reported in the world. Official hospital data tend to underestimate maternal mortality in the community due to underreporting. The sisterhood method survey is an efficient indirect method to assess maternal mortality in rural areas of developing countries.

Adolescent↗
PubMed1992

The synthesis economic fertility model: a latent variable investigation of some critical attributes.

"This study uses Nicaraguan data to estimate a latent variable system of reduced-form demands for births, infant mortality, contraception, nutrition and breastfeeding. The estimates support some of the synthesis extensions to the standard fertility model, such as the concurrent increase of contraception, health, nutrition and fertility and decline in breastfeeding with income increases from initial low levels.... The initial stages of development may experience an increase in family size despite an increase in contraceptive use...as well as a profertility impact of reduced breastfeeding." Data are from a survey of women aged 15-45 that was conducted in Nicaragua from 1977 to 1978.

Americas↗
PubMed1991

Desired and excess fertility in Europe and the United States: indirect estimates from World Fertility Survey data.

This paper presents indirect estimates of desired family size and unwanted births for married and cohabiting women in 12 European countries and the US. An econometric model for censored discrete data is used to estimate the distribution of desired family size from individual observations on children ever-born and total expected births. The data are from the UNECE Comparative Fertility Study of WFS surveys for Europe and the US and originated in national surveys between April 1975-December 1979. Estimates of the bivariate distribution of cumulative and desired fertility are used to compute the proportion of women with excess fertility and the average number of unwanted births for each country. The indirect estimates are compared with those from an analysis of survey responses to questions about desired and unwanted births. Multivariate modes that control for the effects of marriage duration, age at marriage, education, employment status, work experience, and total family income are also reported.

Americas↗
PubMed1993

The cost of the district hospital: a case study in Malawi.

Described in an analysis of the cost to the Ministry of Health of providing district health services in Malawi, with particular emphasis on the district hospital. District resource allocation patterns were assessed by carefully disaggregating district costs by level of care and hospital department. A strikingly low proportion of district recurrent costs was absorbed by salaries and wages (27-39%, depending on the district) and a surprisingly high proportion by medical supplies (24-37%). The most expensive cost centre in the hospital was the pharmacy. A total of 27-39% of total recurrent costs were spent outside the hospital and 61-73% on hospital services. The secondary care services absorbed 40-58% of district recurrent costs. Unit costs by hospital department varied considerably by district, with one hospital being consistently the most expensive and another the cheapest. A total of 3-10 new outpatients could be treated for the average cost of 1 inpatient-day, while 34-55 could be treated for the average cost of 1 inpatient. The efficiency of hospital operations, the scope for redistributing resources districtwide, and the costing methodology are discussed.

Capital Expenditures↗
PubMed2006

Assessment of imaging studies used with radiosurgery: a volumetric algorithm and an estimation of its error. Technical note.

The Gamma Knife has played an increasingly important role in the neurosurgical treatment of patients. Intracranial lesions are not removed by radiosurgery. Rather, the goal of treatment is to induce tumor control. During planning, the creation of dose-volume histograms requires an accurate volumetric analysis of intracranial lesions selected for radiosurgery. In addition, an accurate follow-up imaging analysis of tumor volume is essential for assessing the results of radiosurgery. Nevertheless, sources of volumetric error and their expected magnitudes must be properly understood so that the operator may correctly interpret apparent changes in tumor volume. In this paper, the authors examine the often-neglected contributions of imaging geometry (principally image slice thickness and separation) to overall volumetric error. One of the fundamental sources of volumetric error is that resulting from the geometry of the acquisition protocol. The authors consider the image sampling geometry of tomographic modalities and its contribution to volumetric error through a simulation framework in which a synthetic digital tumor is taken as the primary model. Because the exact volume of the digital phantom can be computed, the volume estimates derived from tomographic "slicing" can be directly compared precisely and independently from other error sources. In addition to providing empirical bounds on volumetric error, this approach provides a tool for guiding the specification of imaging protocols when a specific volumetric accuracy, or volume change sensitivity, for particular structures is sought a priori. Using computational geometry techniques, the volumetric error associated with image acquisition geometry was shown to be dependent on the number of slices through the region of interest (ROI) and the lesion volume. With a minimum of five slices through the ROI, the volume of a compact lesion could be calculated accurately with less than 10% error, which was the predetermined goal for the purposes of computing accurate dose-volume histograms and determining follow-up changes in tumor volume. Accurate dose-volume histograms can be generated and follow-up volumetric assessments performed, assuming accurate lesion delineation, when the object is visualized on at least five axial slices. Volumetric analysis based on fewer than five slices yields unacceptably larger errors (that is, > 10%). These volumetric findings are particularly relevant for radiosurgical treatment planning and follow-up analysis. Through the application of this volumetric methodology and a greater understanding of the error associated with it, neurosurgeons can better perform radiosurgery and assess its outcome.

Algorithms↗
PubMed1982

Fetal hemoglobin: optimum conditions for its estimation by alkali denaturation.

Alkali denaturation is the most commonly used technic to estimate fetal hemoglobin in red blood cells. The Betke and colleagues method (Nature 184: 1959; 1877-78) using cyanmethemoglobin (HiCN) was recommended by an International Committee for Standardization in Hematology for fetal hemoglobin levels between 2 and 40%. We showed that precision with samples containing up to 5% fetal hemoglobin can be considerably improved by measuring the absorbance of HiCN at 420 nm rather than at 540 nm because the molar absorptivity is 10 times greater in the Soret band. To determine optimum conditions for the assay, we studied the kinetics and stoichiometry of conversion of hemoglobin to HiCN with various concentrations and mixtures of ferricyanide, kinetics of alkali denaturation, ammonium sulfate precipitation of denatured HiCN, filtration as opposed to centrifugation for separating denatured HiCN, stability of HiCn in water and KCN solutions, and linearity of absorbance in the Soret band. With our modified procedure, the CV with normal amounts (less than 1%) of fetal hemoglobin improved from 28% to 8.7%. The CVs with 6.8% and 55% fetal hemoglobin were 7.0-4.4% respectively, and linear estimates were obtained with cells containing up to 50% fetal hemoglobin. We conclude that our modified alkali denaturation procedure yields reliable and reproducible estimates of fetal hemoglobin over a wide range of concentrations.

Adult↗
PubMed2002

Technical notes for age estimation using the femur: influence of various analytical conditions on D-aspartic acid contents.

In order to make a better estimate of the individual age using bone samples, we evaluated the effects of various criteria on the analytical measurement of D-aspartic acid contents. Using compact bone from a male femur, we varied six analytical conditions (sample volume, sample particle size, hydrolysis temperature, hydrolysis time, hydrochloric acid volume during hydrolysis, and hydrochloric acid concentration during hydrolysis). D-form/L-form ratios were affected most by hydrolysis temperature (estimated age differences were 3.03 years/ degrees C), followed in order by hydrochloric acid volume (1.44 years/ml) and hydrochloric acid concentration (0.69 years/0.1 M). Larger sample particle sizes and hydrochloric acid volumes during hydrolysis tended to result in lower racemization rates. Nonetheless, within a range of 5-50 mg, sampling volume did not affect the detected D-aspartic acid contents. Since the racemization reaction rate in femur compact bone is slower than in dentin, bone samples seem to be more greatly influenced by analytic conditions than dentin. Tests must therefore be performed with caution, especially with regard to the hydrolysis temperature, hydrochloric acid volume and concentration when estimating age using femur samples.

D-Aspartic Acid↗
PubMed1997

Technical note. Comparison between estimated worn clothing insulation and required calculated clothing insulation in moderately cold environments (0 degree C < or = ta < or = +15 degrees C).

Six female and 33 male workers of the food industry (16-55 years), divided into three groups according to climatic conditions at the workplaces, were monitored during a typical shift. Fourteen subjects worked continuously in 0-7 degrees C, 18 in 13-15 degrees C and seven moved frequently between these climatic areas. Mean metabolic rates, heart rates, rectal temperatures and skin temperatures at the trunk and at the feet were similar between each of the three groups. Considerable differences between estimated clothing insulations worn and calculated required clothing insulations (IREQneutral) were statistically analyzed. The results suggest that--apart from a limited overestimation--this discrepancy is mainly related to the difference between time-adjusted averages of metabolic rates of the single activities and the respective daily minimum suggesting the need for an adequate weighting for the metabolic rates, particularly if workers are at least temporarily exposed to air temperatures of more than 7-13 degrees C.

Adolescent↗