330 research outputs found
Developmental origins of midlife grip strength: findings from a birth cohort study
No full textBACKGROUND: There is growing evidence that the prenatal environment has long-term effects on adult grip strength, but little is known about the effects of the postnatal environment. We tested whether prepubertal growth, pubertal growth, or the development of motor and cognitive capabilities was associated with midlife muscle strength independently of other determinants of grip strength. METHODS: Handgrip strength and body size were measured in a representative British sample of 1406 men and 1444 women 53 years old with prospective childhood data. Normal regression models were used to examine the effects of birth weight, postnatal height and weight gain before 7 years and between 7 and 15 years, motor milestones and cognitive ability on grip strength at age 53, taking account of lifetime social class, current physical activity, and health status. RESULTS: Birth weight and prepubertal height gain were associated with midlife grip strength, independently of later weight and height gain and other determinants. Pubertal growth was also independently associated with midlife grip strength; for men weight gain during puberty was beneficial, whereas for women it was height gain. Those participants with earlier infant motor development had better midlife grip strength, which was partly confounded by the growth trajectory. CONCLUSIONS: This study showed that components of prenatal, prepubertal, and pubertal growth have long-term effects on midlife grip strength. To the extent that these associations are modifiable, interventions in childhood that help to build muscle mass and strength, such as increased physical exercise, may have long-term beneficial effects on adult muscle strength and may help to prevent sarcopenia, disability, and frailty in later lif
Developmental origins of midlife physical performance: evidence from a British birth cohort
No full textThe authors hypothesized that 1) physical growth, as a marker of the early development of muscle fibers, and 2) advanced childhood motor and cognitive abilities, as markers of central nervous system development, would be positively related to midlife standing balance and chair rising, independently of later life experiences. They tested these hypotheses in a representative British sample of 1,374 men and 1,410 women aged 53 years in 1999 with prospective childhood measures of heights and weights, age at first standing and walking, cognitive ability, and motor coordination. Weight gain before age 7 years was positively related to adult performance in men but not women, independently of later body size, social class, physical activity, and health status. Attainment of motor milestones at the modal age and higher scores on tests of cognitive ability and motor coordination were associated with better performance, independently of other factors. This study is the first to show that childhood growth and development affect midlife performance; prevention of disability and frailty in later life may need to start earl
From intervention to impact: modelling the potential mortality impact achievable by different long-lasting, insecticide-treated net delivery strategies.
No full textBACKGROUND: The current target of universal access to long-lasting, insecticide-treated nets (LLIN) is 80% coverage to reduce malaria deaths by 75% by 2015. So far, campaigns have been the main channel for large-scale delivery of LLINs, however the World Health Organization has recommended that equal priority should be given to delivery via routine antenatal care (ANC) and immunization systems (EPI) to target pregnant women and children from birth. These various channels of LLIN delivery are targeted to children of different ages. Since risk of mortality varies with child age and LLIN effectiveness declines with net age, it was hypothesized that the age at which a child receives a new LLIN, and therefore the delivery channel, is important in optimizing the health impact of a net. METHODS: A simple dynamic mathematical model was developed of delivery and impact of LLINs among children under five years of age and their household members, incorporating data on age-specific malaria death rates, net use by household structure, and net efficacy over time. RESULTS: The presented analysis finds that supplementing a universal mass campaign with extra ANC delivery would achieve a 1.4 times higher mortality reduction than campaign delivery alone, reflecting that children born in the years between campaigns would otherwise have access to old nets or no nets at an age of high risk. The relative advantage of supplementary ANC delivery is still present though smaller if malaria transmission levels are lower or if there is a strong mass effect achieved by mass campaigns. CONCLUSION: These results indicate that LLIN delivery policies must take into account the age of greatest malaria risk. Emphasis should be placed on supporting routine delivery of LLINs to young children as well as campaigns
How typology allows for a new analysis of the verb phrase in Burmese
No full textInternational audienceBurmese has been studied by westerner scholars since 18e century. Recent works containing good description of the language (or part of the language) are Allott (1965), Okell (1969), Bernot (1980), Wheatley (1982), Bernot et al (2001), Allott &. Okell (2001). However comparison of the description made by these authors leads to different analysis of the verbal phrase. For instance the list of optional verbal morphemes (particles and auxiliaries) varies depending of the criteria used by the author for his analysis. Moreover, as in many Asian languages, groups of verbs not separated by connectors exist in Burmese. These verbal phrases composed by several verb roots have identical form in surface. However, they cannot be analyzed in the same way. They can correspond to lexical expressions, or compounds and be listed in dictionaries. The verbal phrase may be analyzed as a prototypical serial verbs construction (SVC), here is to say, part of one clause only which refers to a unique event. Third possibility : some of the verb roots can be grammaticalized and be considered as auxiliaries. Given the identical surface forms and the different under-laying structures, we look for a model allowing us to treat together phenomenon traditionally analyzed separately. Therefore, the notion of serial verbs construction (CVS) recently developed by Déchaine (1993), Durie (1997) or, Aikhenvald & Dixon (in press) among others help us to build the adequate frame for a more global approach of the VP in Burmese
Factors associated with episodes of low back pain in elite alpine ski racers: A prospective case series
No full textBackground and Aim
Given the high risk of low back pain (LBP) in alpine ski racers, this study investigated episodes of LBP over a competitive ski season and examined associated factors.
Methods
A prospective non-consecutive case series (n = 5) of international alpine ski racers was conducted over 36 weeks. Participant characteristics, previous injury, and measure of trunk strength were collected at the start of the season whilst information on LBP was collected fortnightly. Descriptive statistics and odds ratio (OR) from a generalised linear model are presented.
Results
Three female and two male cases were involved. Response rates ranged from 83 to 94%. All cases reported experiencing LBP (6.7–88.0% of responses). Most cases continued normal training or competition, though training was reduced (cases 2 and 5) or stopped (case 5) due to LBP in some cases. All but one case reported LBP impacting performance (minor to major) extent. Older (OR = 0.43, p = 0.048) and male (OR = 0.09, p < 0.001) racers had less odds of an episode of LBP. Taller individuals (OR = 1.39, p = 0.004), the pre-season phase (OR = 5.12, p = 0.045) and on-snow training hours (OR = 1.07, p = 0.192) were associated with greater odds ofepisodes of LBP. Inconclusive associations were found for trunk strength, competition, and off-snow training (OR = 0.54–1.01, p = 0.215–0.602).
Conclusion
Alpine ski racers commonly report low back pain, necessitating training modifications and impacting performance. Practitioners working in alpine skiing should consider strategies to better manage the pre-season period and prolonged periods of on-snow training, particularly for athletes with known risk factors (e.g. taller individuals) or a history of LBP
Dual-calibrated fMRI measurement of absolute cerebral metabolic rate of oxygen consumption and effective oxygen diffusivity
No full textDual-calibrated fMRI is a multi-parametric technique that allows for the quantification of the resting oxygen extraction fraction (OEF), the absolute rate of cerebral metabolic oxygen consumption (CMRO 2 ), cerebral vascular reactivity (CVR) and baseline perfusion (CBF). It combines measurements of arterial spin labelling (ASL) and blood oxygenation level dependent (BOLD) signal changes during hypercapnic and hyperoxic gas challenges. Here we propose an extension to this methodology that permits the simultaneous quantification of the effective oxygen diffusivity of the capillary network (D C ). The effective oxygen diffusivity has the scope to be an informative biomarker and useful adjunct to CMRO 2 , potentially providing a non-invasive metric of microvascular health, which is known to be disturbed in a range of neurological diseases. We demonstrate the new method in a cohort of healthy volunteers (n = 19) both at rest and during visual stimulation. The effective oxygen diffusivity was found to be highly correlated with CMRO 2 during rest and activation, consistent with previous PET observations of a strong correlation between metabolic oxygen demand and effective diffusivity. The increase in effective diffusivity during functional activation was found to be consistent with previously reported increases in capillary blood volume, supporting the notion that measured oxygen diffusivity is sensitive to microvascular physiology
Early motherhood and mental health in midlife: a study of British and American cohorts.
No full textOBJECTIVES: Examine the relationship between early age at first birth and mental health among women in their fifties. METHODS: Analysis of data on women from a British 1946 birth cohort study and the U.S. Health and Retirement Study birth cohort of 1931-1941. RESULTS: In both samples a first birth before 21 years, compared to a later first birth, is associated with poorer mental health. The association between early first birth and poorer mental health persists in the British study even after controlling for early socioeconomic status, midlife socioeconomic status and midlife health. In the U.S. sample, the association becomes non-significant after controlling for educational attainment. CONCLUSIONS: Early age at first birth is associated with poorer mental health among women in their fifties in both studies, though the pattern of associations differs
A general framework for optimizing arterial spin labeling MRI experiments
No full textPurpose: Arterial spin labeling (ASL) MRI is a non‐invasive perfusion imaging technique that is inherently SNR limited, so scan protocols ideally need to be rigorously optimized to provide the most accurate measurements. A general framework is presented for optimizing ASL experiments to achieve optimal accuracy for perfusion estimates and, if required, other hemodynamic parameters, within a fixed scan time. The effectiveness of this framework is then demonstrated by optimizing the post‐labeling delays (PLDs) of a multi‐PLD pseudo‐continuous ASL experiment and validating the improvement using simulations and in vivo data.
Theory and Methods: A simple framework is proposed based on the use of the Cramér‐Rao lower bound to find the protocol design which minimizes the predicted parameter estimation errors. Protocols were optimized for cerebral blood flow (CBF) accuracy or both CBF and arterial transit time (ATT) accuracy and compared to a conventional multi‐PLD protocol, with evenly spaced PLDs, and a single‐PLD protocol, using simulations and in vivo experiments in healthy volunteers.
Results: Simulations and in vivo data agreed extremely well with the predicted performance of all protocols. For the in vivo experiments, optimizing for just CBF resulted in a 48% and 15% decrease in CBF errors, relative to the reference multi‐PLD and single‐PLD protocols, respectively. Optimizing for both CBF and ATT reduced CBF errors by 37%, without a reduction in ATT accuracy, relative to the reference multi‐PLD protocol.
Conclusion: The presented framework can effectively design ASL experiments to minimize measurement errors based on the requirements of the scan
Submicroscopic infection in Plasmodium falciparum-endemic populations: a systematic review and meta-analysis.
No full textINTRODUCTION: Light microscopy examination of blood slides is the main method of detecting malaria infection; however, it has limited sensitivity. Low-density infections are most likely to be missed, but they contribute to the infectious reservoir. Quantifying these submicroscopic infections is therefore key to understanding transmission dynamics and successfully reducing parasite transmission. METHODS: We conducted a systematic review of endemic population surveys in which P. falciparum prevalence had been measured by both microscopy and a more-sensitive polymerase chain reaction (PCR)-based technique. The combined microscopy:PCR prevalence ratio was estimated by random-effects meta-analysis, and the effect of covariates was determined by meta-regression. RESULTS: Seventy-two pairs of prevalence measurements were included in the study. The prevalence of infection measured by microscopy was, on average, 50.8% (95% confidence interval [CI], 45.2%-57.1%) of that measured by PCR. For gametocyte-specific detection, the microscopy prevalence was, on average, 8.7% (95% CI, 2.8%-26.6%) of the prevalence measured by PCR. A significantly higher percentage of total infections was detected by microscopy in areas of high, compared with low, transmission (74.5% when the prevalence determined by PCR was >75% versus 12.0% when the prevalence determined by PCR was <10%). DISCUSSION: Microscopy can miss a substantial proportion of P. falciparum infections in surveys of endemic populations, especially in areas with low transmission of infection. The extent of the submicroscopic reservoir needs to be taken into account for effective surveillance and control
Review of "The universal Burmese-English-Pali dictionary"
No full textStudents of Burmese in the English speaking world have been blessed with a new Burmese-English dictionary: The Universal Burmese-English-Pali Dictionary by U Hoke Sein (for details see References below). The preface reveals that we nearly missed it. The author's intention was to write a Burmese-Pali dictionary, a sequel to his Pali-Burmese dictionary, but the Ara-sahlciut Hsaya-daw (long may he flourish) seems to have provided the stimulus that led U Hoke Sein (HS) to insert an English gloss between the Burmese entry and the Pali equivalent (p.ja). The result is the present Burmese-English-Pali dictionary. Its author is a distinguished lawyer, and the dictionary took him 30 years to compile (p.1066). For its last seven years he worked at it full time (p.ja).Published versio
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