750 research outputs found
Advanced superalloy protection systems evaluation Final report
Metalliding parameters developed for sequential deposition of manganese, aluminum, and tantalum alloys as protective coatings for superalloy
Commercialization of the land remote sensing system: An examination of mechanisms and issues
In September 1982 the Secretary of Commerce was authorized (by Title II of H.R. 5890 of the 97th Congress) to plan and provide for the management and operation of the civil land remote sensing satellite systems, to provide for user fees, and to plan for the transfer of the ownership and operation of future civil operational land remote sensing satellite systems to the private sector. As part of the planning for transfer, a number of approaches were to be compared including wholly private ownership and operation of the system by an entity competitively selected, mixed government/private ownership and operation, and a legislatively-chartered privately-owned corporation. The results of an analysis and comparison of a limited number of financial and organizational approaches for either transfer of the ownership and operation of the civil operational land remote sensing program to the private sector or government retention are presented
Frailty and Risk of Falls, Fracture, and Mortality in Older Women: The Study of Osteoporotic Fractures
Background. A standard phenotype of frailty was associated with an increased risk of adverse outcomes including mortality in a recent study of older adults. However, the predictive validity of this phenotype for fracture outcomes and across risk subgroups is uncertain. Methods. To determine whether a standard frailty phenotype was independently associated with risk of adverse health outcomes in older women and to evaluate the consistency of associations across risk subgroups defined by age and body mass index (BMI), we ascertained frailty status in a cohort of 6724 women ≥ 69 years and followed them prospectively for incident falls, fractures, and mortality. Frailty was defined by the presence of three or more of the following criteria: unintentional weight loss, weakness, self-reported poor energy, slow walking speed, and low physical activity. Incident recurrent falls were defined as at least two falls during the subsequent year. Incident fractures (confirmed with x-ray reports), including hip fractures, and deaths were ascertained during an average of 9 years of follow-up. Results. After controlling for multiple confounders such as age, health status, medical conditions, functional status, depressive symptoms, cognitive function, and bone mineral density, frail women were subsequently at increased risk of recurrent falls (multivariate odds ratio = 1.38, 95% confidence interval [CI], 1.02-1.88), hip fracture (multivariate hazards ratio [MHR] = 1.40, 95% CI, 1.03-1.90), any nonspine fracture (MHR = 1.25, 95% CI, 1.05-1.49), and death (MHR = 1.82, 95% CI, 1.56-2.13). The associations between frailty and these outcomes persisted among women ≥ 80 years. In addition, associations between frailty and an increased risk of falls, fracture, and mortality were consistently observed across categories of BMI, including BMI ≥ 30 kg/m2. Conclusion. Frailty is an independent predictor of adverse health outcomes in older women, including very elderly women and older obese wome
UK Housing Market: Time Series Processes with Independent and Identically Distributed Residuals
The paper examines whether a univariate data generating process can be identified which explains the data by having residuals that are independent and identically distributed, as verified by the BDS test. The stationary first differenced natural log quarterly house price index is regressed, initially with a constant variance and then with a conditional variance. The only regression function that produces independent and identically distributed standardised residuals is a mean process based on a pure random walk format with Exponential GARCH in mean for the conditional variance. There is an indication of an asymmetric volatility feedback effect but higher frequency data is required to confirm this. There could be scope for forecasting the index but this is tempered by the reduction in the power of the BDS test if there is a non-linear conditional variance process
Epidemiology of fractures in Armenia: development of a country-specific FRAX model and comparison to its surrogate
Summary: Fracture probabilities derived from the surrogate FRAX model for Armenia were compared to those from the model based on regional estimates of the incidence of hip fracture. Disparities between the surrogate and authentic FRAX models indicate the importance of developing country-specific FRAX models. Despite large differences between models, differences in the rank order of fracture probabilities were minimal. Objective: Armenia has relied on a surrogate FRAX model based on the fracture epidemiology of Romania. This paper describes the epidemiology of fragility fractures in Armenia used to create an Armenia-specific FRAX model with an aim of comparing this new model with the surrogate model. Methods: We carried out a population-based study in two regions of Armenia (Ararat and Vayots Dzor representing approximately 11% of the country’s population). We aimed to identify all low-energy fractures: retrospectively from hospital registers in 2011–2012 and prospectively in 2013 with the inclusion of primary care sources. Results: The differences in incidence between the surveys with and without data from primary care suggested that 44% of patients sustaining a hip fracture did not receive specialized medical care. A similar proportion of forearm and humeral fractures did not come to hospital attention (48 and 49%, respectively). Only 57.7% of patients sustaining a hip fracture were hospitalized. In 2013, hip fracture incidence at the age of 50 years or more was 201/100,000 for women and 136/100,000 for men, and age- and sex-specific rates were incorporated into the new “authentic” FRAX model for Armenia. Compared to the surrogate model, the authentic model gave lower 10-year fracture probabilities in men and women aged less than 70 years but substantially higher above this age. Notwithstanding, there were very close correlations in fracture probabilities between the surrogate and authentic models ( >  0.99) so that the revisions had little impact on the rank order of risk. Conclusion: A substantial proportion of major osteoporotic fractures in Armenia do not come to hospital attention. The disparities between surrogate and authentic FRAX models indicate the importance of developing country-specific FRAX models. Despite large differences between models, differences in the rank order of fracture probabilities were minimal
Epidemiology of hip fracture in Belarus: development of a country-specific FRAX model and its comparison to neighboring country models
Summary
Fracture probabilities resulting from the newly generated FRAX model for Belarus based on regional estimates of the hip fracture incidence were compared with FRAX models of neighboring countries. Differences between the country-specific FRAX patterns and the rank orders of fracture probabilities were modest.
Objective
This paper describes the epidemiology of hip fractures in Belarus that was used to develop the country-specific fracture prediction FRAX® tool and illustrates its features compared to models for the neighboring countries of Poland, Russia, and Lithuania.
Methods
We carried out a population-based study in a region of Belarus (the city of Mozyr) representing approximately 1.2% of the country’s population. We aimed to identify all hip fractures in 2011–2012 from hospital registers and primary care sources. Age- and sex-specific incidence and national mortality rates were incorporated into a FRAX model for Belarus. Fracture probabilities were compared with those derived from FRAX models in neighboring countries.
Results
The estimated number of hip fractures nationwide in persons over the age of 50 years for 2015 was 8250 in 2015 and is predicted to increase to 12,918 in 2050. The annual incidence of fragility hip fractures in individuals aged 50 years or more was 24.6/10,000 for women and 14.6/10,000 for men, standardized to the world population. The comparison with FRAX models in neighboring countries showed that hip fracture probabilities in men and women in Belarus were similar to those in Poland, Russia, and Lithuania. The difference in incidence rates between the surveys including or excluding data from primary care suggested that 29.1% of patients sustaining a hip fracture were not hospitalized and, therefore, did not receive specialized medical care.
Conclusion
A substantial proportion of hip fractures in Belarus does not come to hospital attention. The FRAX model should enhance accuracy of determining fracture probability among the Belarus population and help guide decisions about treatment
The effects of moderate alcohol supplementation on estrone sulfate and DHEAS in postmenopausal women in a controlled feeding study
BACKGROUND: We have demonstrated that moderate alcohol consumption (15 g/d, 30 g/d) for 8 weeks resulted in significantly increased levels of serum estrone sulfate and DHEAS in 51 postmenopausal women in a randomized, placebo-controlled trial. We now report on the relationships between serum estrone sulfate and dehydroepiandrosterone sulfate (DHEAS) levels after 4 weeks of moderate alcohol supplementation, and compare the results to the 8 weeks data to elucidate time-to-effect differences. METHODS: Postmenopausal women (n = 51) consumed 0 (placebo), 15 (1 drink), and 30 (2 drinks) g alcohol (ethanol)/ day for 8 weeks as part of a controlled diet in a randomized crossover design. Blood samples were drawn at baseline, at 4 weeks and at 8 weeks. Changes in estrone sulfate and DHEAS levels from placebo to 15 g and 30 g alcohol per day were estimated using linear mixed models. RESULTS AND DISCUSSION: At week 4, compared to the placebo, estrone sulfate increased an average 6.9% (P = 0.24) when the women consumed 15 g of alcohol per day, and 22.2% (P = 0.0006) when they consumed 30 g alcohol per day. DHEAS concentrations also increased significantly by an average of 8.0% (P < 0.0001) on 15 g of alcohol per day and 9.2% (P < 0.0001) when 30 g alcohol was consumed per day. Trend tests across doses for both estrone sulfate (P = 0.0006) and DHEAS (P < 0.0001) were significant. We found no significant differences between the absolute levels of serum estrone sulfate at week 4 versus week 8 (P = 0.32) across all doses. However, absolute DHEAS levels increased from week 4 to week 8 (P < 0.0001) at all three dose levels. CONCLUSIONS: These data indicate that the hormonal effects due to moderate alcohol consumption are seen early, within 4 weeks of initiation of ingestion
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