272 research outputs found

    ACCORD Glycemia Results Continue to Puzzle

    Get PDF

    Longitudinal associations between incident lumbar spine MRI findings and chronic low back pain or radicular symptoms: retrospective analysis of data from the longitudinal assessment of imaging and disability of the back (LAIDBACK)

    Get PDF
    BACKGROUND: There are few longitudinal cohort studies examining associations between incident MRI findings and incident spine-related symptom outcomes. Prior studies do not discriminate between the two distinct outcomes of low back pain (LBP) and radicular symptoms. To address this gap in the literature, we conducted a secondary analysis of existing data from the Longitudinal Assessment of Imaging and Disability of the Back (LAIDBACK). The purpose of this study was to examine the association of incident lumbar MRI findings with two specific spine-related symptom outcomes: 1) incident chronic bothersome LBP, and 2) incident radicular symptoms such as pain, weakness, or sensation alterations in the lower extremity. METHODS: The original LAIDBACK study followed 123 participants without current LBP or sciatica, administering standardized MRI assessments of the lumbar spine at baseline and at 3-year follow-up, and collecting information on participant-reported spine-related symptoms and signs every 4 months for 3 years. These analyses examined bivariable and multivariable associations between incident MRI findings and symptom outcomes (LBP and radicular symptoms) using logistic regression. RESULTS: Three-year cumulative incidence of new MRI findings ranged between 2 and 8%, depending on the finding. Incident annular fissures were associated with incident chronic LBP, after adjustment for prior back pain and depression (adjusted odds ratio [OR] 6.6; 95% confidence interval [CI] 1.2-36.9). All participants with incident disc extrusions (OR 5.4) and nerve root impingement (OR 4.1) reported incident radicular symptoms, although associations were not statistically significant. No other incident MRI findings showed large magnitude associations with symptoms. CONCLUSIONS: Even when applying more specific definitions for spine-related symptom outcomes, few MRI findings showed large magnitude associations with symptom outcomes. Although incident annular fissures, disc extrusions, and nerve root impingement were associated with incident symptom outcomes, the 3-year incidence of these MRI findings was extremely low, and did not explain the vast majority of incident symptom cases

    Age-specific trends in cardiovascular mortality rates in Australia between 1980 and 2005

    Full text link
    Aim: Recent analyses suggest the decline in coronary heart disease (CHD) mortality rates is slowing in younger age groups in countries such as the UK and US. We aimed to assess recent mortality rate trends in all circulatory disease and its subtypes in Australia. Methods: Annual all circulatory, CHD, and cerebrovascular disease mortality rates between 1980 and 2005 for Australia were analysed. Data were stratified by sex and ten-year age group (age 35 to 85+). The annual rate of change and significant changes in trends were identified using joinpoint Poisson regression. Results: Age standardised all circulatory disease mortality rates continue to decline in Australia, falling from 441 per 100,000 in 1980 to 145 per 100,000 in 2005 for males and from 264 per 100,000 to 96 per 100,000 for females. The rate of decline from both CHD and cerebrovascular disease appears to be stable or accelerating for individuals aged 55 years and over. However, the decline in young men and women aged 35-54 years is slowing for CHD and cerebrovascular disease mortality alike (except cerebrovascular disease mortality in males aged 35-44). For females aged 35-44 and 45-54 there has been no change in the cerebrovascular mortality rate since 1993 and 1999, respectively. Conclusions: In Australia, whilst in older adults the decline in cardiovascular mortality rates is generally accelerating, in younger adults it appears to be slowing. It will be important to identify the causes of these trends

    DESIGN OF NEW CASTING ALLOYS OF Al-Mg-Si-Mn SYSTEM WITH ALLOYING ADDITIONS, ITS STRUCTURE AND MECHANICAL PROPERTIES

    Get PDF
    The strength of Al-Mg-Si-Mn casting alloy strongly depends on Mg content in solid solution and precipitation of strengthening phases. Alloys with the nominal composition AlMg5Si2Mn with addition of Li and Ti+Zr were studied by means of differential scanning calorimetry (DSC), transmission electron microscopy (TEM) and energy dispersive X-Ray analysis (EDX). DSC measurements show that the eutectic melting temperature was about 595°C and it is higher than that of commercial A356 casting alloy. The macro- and microhardness tests show that in as-cast state hardness were higher than for A356 and continuously growth during artificial aging. TEM investigations reveal that during artificial aging three different precipitation types are forms in the alloy matrix. Two of them belong to the different structures of Mg2Si precipitates. Appearance of the third one identified as d’-Al3Li phase represent that Al-Mg-Si system can be successfully used for designing of Li-containing casting alloy which is not developed yet

    EFFECT OF ADDITIONAL ALLOYING AND HEAT TREATMENT ON THE PHASE COMPOSITION AND MORPHOLOGY IN Al-Mg-Si TYPE CASTING ALLOY

    Get PDF
    The structure of permanent mold and high pressure die castings of the AlMg5Si2Mn alloy after alloying with Li and Sc has been investigated by scanning and transmission electron microscopy, hardness and microhardness measurements, energy dispersive X-ray analysis. Three conditions, as cast, solution treated and aged, were investigated. It was shown that in as-cast state, the structure of an alloy having the nominal composition AlMg5Si2Mn consists of four phases: first – the Al based solid solution, second – the (Al)+(Mg2Si) eutectic, third – the primary Mg2Si crystals and fourth – the a-Al(Mn, Fe)Si phase. Similar phases were observed in the alloys containing Sc or Li. After two days of storing in an as-cast condition, the solid solution in all tested alloys decomposesand forms zebra-crossing shaped precipitates. TEM examinations revealed that these precipitates nucleate heterogeneously on dislocations. The solution treatment at 575.0°C results in spheroidization of the Mg2Si lamellas, dissolution of the precipitates and formation of a-Al(Mn, Fe)Si dispersoids, nucleating on the surfaces of Mg2Si lamellas. In the Sc containing alloys, the formation of Al3Sc was detected after 120 min soaking. Further heating resulted in the growth of these precipitates. Aging of the Al-Mg-Si alloys leads to an increase of hardness in all studied alloys. This effect is mainly related to precipitation strengthening, via solid solution decomposition and formation of b’’-phase. In Li-alloyed specimens, plates of b Mg2Si phase were observed together with small cubic-shaped d’ Al3Li precipitates. The structure of permanent mould and high pressure die castings of the AlMg5Si2Mn alloy after alloying with Li and Sc has been investigated by scanning and transmission electron microscopy, hardness and microhardness measurements, energy dispersive X-ray analysis. Three conditions, as cast, solution treated and aged, were investigated. It was shown that in as-cast state, the structure of an alloy having the nominal composition AlMg5Si2Mn consists of four phases: first - the Al based solid solution, second - the (Al)+(Mg2Si) eutectic, third - the primary Mg2Si crystals and fourth – the  phase. Similar phases were observed in the alloys containing Sc or Li. After two days of storing in an as-cast condition, the solid solution in all tested alloys decomposes and forms zebra-crossing shaped precipitates. TEM examinations revealed that these precipitates nucleate heterogeneously on dislocations. The solution treatment at 575.0°C results in spheroidization of the eutectic, dissolution of the precipitates and formation of  dispersoids, nucleating on the surfaces of Mg2Si lamellas. In the Sc containing alloys, the formation of Al3Sc was detected after 120 min soaking. Further heating resulted in the growth of these precipitates. Aging of the Al-Mg-Si alloys leads to an increase of hardness in all studied alloys. This effect is mainly related to precipitation strengthening, via solid solution decomposition and formation of bÂČ-phase. In Li-alloyed specimens, plates of b Mg2Si phase were observed together with small cubic-shaped dÂą Al3Li precipitates

    Central obesity as a precursor to the metabolic syndrome in the AusDiab study and Mauritius

    Full text link
    Evidence from epidemiologic studies that central obesity precedes future metabolic change and does not occur concurrently with the appearance of the blood pressure, glucose, and lipid abnormalities that characterize the metabolic syndrome (MetS) has been lacking. Longitudinal surveys were conducted in Mauritius in 1987, 1992, and 1998, and in Australia in 2000 and 2005 (AusDiab). This analysis included men and women (aged 25 years) in three cohorts: AusDiab 2000&ndash;2005 (n = 5,039), Mauritius 1987&ndash;1992 (n = 2,849), and Mauritius 1987&ndash;1998 (n = 1,999). MetS components included waist circumference, systolic blood pressure, fasting and 2-h postload plasma glucose, high-density lipoprotein (HDL) cholesterol, triglycerides, and homeostasis model assessment of insulin sensitivity (HOMA-S) (representing insulin sensitivity). Linear regression was used to determine which baseline components predicted deterioration in other MetS components over 5 years in AusDiab and 5 and 11 years in Mauritius, adjusted for age, sex, and ethnic group. Baseline waist circumference predicted deterioration (P &lt; 0.01) in four of the other six MetS variables tested in AusDiab, five of six in Mauritius 1987&ndash;1992, and four of six in Mauritius 1987&ndash;1998. In contrast, an increase in waist circumference between baseline and follow-up was only predicted by insulin sensitivity (HOMA-S) at baseline, and only in one of the three cohorts. These results suggest that central obesity plays a central role in the development of the MetS and appears to precede the appearance of the other MetS components.<br /

    A Prospective Study of Lupus and Rheumatoid Arthritis in Relation to Deployment in Support of Iraq and Afghanistan: The Millennium Cohort Study

    Get PDF
    The objective of this study was to prospectively assess the association between deployment in support of the operations in Iraq and Afghanistan and newly reported lupus and rheumatoid arthritis while also considering the effects of demographic, behavioral, and occupational characteristics. A total of 77,047 (2001–2003) and 31,110 (2004–2006) participants completed the baseline Millennium Cohort questionnaire and were resurveyed approximately every 3 years. Longitudinal analyses were used to assess the adjusted association between deployment to Iraq and Afghanistan with and without combat exposures and newly reported disease. After adjusting, deployment was not significantly associated with newly reported lupus compared with nondeployers. However, compared with nondeployers, deployers with and without combat exposures were significantly less likely to newly report rheumatoid arthritis. Women, non-Hispanic black, and Hispanic participants had a significantly elevated risk for both diseases. Overall, deployment was not associated with an increased risk of newly reported lupus or rheumatoid arthritis
    • 

    corecore