Sea-level constraints on the amplitude and source distribution of Meltwater Pulse 1A.

During the last deglaciation, sea levels rose as ice sheets retreated. This climate transition was punctuated by periods of more intense melting; the largest and most rapid of these—Meltwater Pulse 1A—occurred about 14,500 years ago, with rates of sea-level rise reaching approximately 4 m per century1, 2, 3. Such rates of rise suggest ice-sheet instability, but the meltwater sources are poorly constrained, thus limiting our understanding of the causes and impacts of the event4, 5, 6, 7. In particular, geophysical modelling studies constrained by tropical sea-level records1, 8, 9 suggest an Antarctic contribution of more than seven metres, whereas most reconstructions10 from Antarctica indicate no substantial change in ice-sheet volume around the time of Meltwater Pulse 1A. Here we use a glacial isostatic adjustment model to reinterpret tropical sea-level reconstructions from Barbados2, the Sunda Shelf3 and Tahiti1. According to our results, global mean sea-level rise during Meltwater Pulse 1A was between 8.6 and 14.6 m (95% probability). As for the melt partitioning, we find an allowable contribution from Antarctica of either 4.1 to 10.0 m or 0 to 6.9 m (95% probability), using two recent estimates11, 12 of the contribution from the North American ice sheets. We conclude that with current geologic constraints, the method applied here is unable to support or refute the possibility of a significant Antarctic contribution to Meltwater Pulse 1A

Differential Geometry for Model Independent Analysis of Images and Other Non-Euclidean Data: Recent Developments

This article provides an exposition of recent methodologies for nonparametric analysis of digital observations on images and other non-Euclidean objects. Fr\'echet means of distributions on metric spaces, such as manifolds and stratified spaces, have played an important role in this endeavor. Apart from theoretical issues of uniqueness of the Fr\'echet minimizer and the asymptotic distribution of the sample Fr\'echet mean under uniqueness, applications to image analysis are highlighted. In addition, nonparametric Bayes theory is brought to bear on the problems of density estimation and classification on manifolds

Subclonal TP53 copy number is associated with prognosis in multiple myeloma

Multiple myeloma (MM) is a genetically heterogeneous cancer of bone marrow plasma cells with variable outcome. To assess the prognostic relevance of clonal heterogeneity of TP53 copy number, we profiled tumors from 1777 newly diagnosed Myeloma XI trial patients with multiplex ligation-dependent probe amplification (MLPA). Subclonal TP53 deletions were independently associated with shorter overall survival, with a hazard ratio of 1.8 (95% confidence interval, 1.2-2.8; P = .01). Clonal, but not subclonal, TP53 deletions were associated with clinical markers of advanced disease, specifically lower platelet counts (P < .001) and increased lactate dehydrogenase (P < .001), as well as a higher frequency of features indicative of genomic instability, del(13q) (P = .002) or del(1p) (P = .006). Biallelic TP53 loss-of-function by mutation and deletion was rare (2.4%) and associated with advanced disease. We present a framework for identifying subclonal TP53 deletions by MLPA, to improve patient stratification in MM and tailor therapy, enabling management strategies

HIV, STI prevalence and risk behaviours among women selling sex in Lahore, Pakistan

<p>Abstract</p> <p>Background</p> <p>More than 340 million cases of curable sexually transmitted infections (STIs) were estimated to have occurred worldwide in 1995. Previous studies have shown that the presence of other concomitant STIs increases the likelihood of HIV transmission. The first national study of STIs conducted in Pakistan in 2004 revealed a high burden of STIs among women selling sex. The HIV epidemic in Pakistan has thus far followed the "Asian epidemic model". Earlier studies among women selling sex have shown a low prevalence of HIV coupled with a low level of knowledge about AIDS. The aim of our study was to estimate the prevalence of HIV and STIs, and assess knowledge and risk behaviours related to HIV/STI, among women selling sex in Lahore, Pakistan.</p> <p>Methods</p> <p>A total of 730 participants were recruited through respondent-driven sampling. The participants were women selling sex in three areas (referred to as "A", "B", and "C") of Lahore. A structured questionnaire addressing demographic information, sexual life history, sexual contacts, and knowledge and practices related to HIV/STI prevention was administered by face-to-face interview. Biological samples were obtained from all participants and tested for HIV, <it>Treponema pallidum</it>, <it>Neisseria gonorrhoeae</it>, <it>Chlamydia trachomatis </it>and <it>Trichomonas vaginalis</it>. Pearson's chi-square and multivariable logistic regression analysis were performed to test associations between potential risk factors and specified diagnosed infections.</p> <p>Results</p> <p>The prevalence of HIV infection was 0.7%, <it>T pallidum </it>4.5%, <it>N gonorrhoeae </it>7.5%, <it>C trachomatis </it>7.7% and <it>T vaginalis </it>5.1%. The participants had been selling sex for a median period of seven years and had a median of three clients per day. Sixty five percent of the participants reported that they "Always use condom". The median fee per sexual contact was Rs. 250 (3 Euro). Compared to Areas A and C, women selling sex in Area B had a significantly higher risk of chlamydial infection, gonorrhoea and trichomoniasis. Among the participants, 37% had correct knowledge about HIV/AIDS transmission and its prevention.</p> <p>Conclusions</p> <p>The prevalence of HIV was <1%, and of any other STI 18.5% among participating women selling sex in Lahore, Pakistan. A reasonably high condom use, a relatively low number of sexual partners, and a relatively low prevalence of STIs might have contributed to the low HIV prevalence.</p

Measuring inequality: tools and an illustration

BACKGROUND: This paper examines an aspect of the problem of measuring inequality in health services. The measures that are commonly applied can be misleading because such measures obscure the difficulty in obtaining a complete ranking of distributions. The nature of the social welfare function underlying these measures is important. The overall object is to demonstrate that varying implications for the welfare of society result from inequality measures. METHOD: Various tools for measuring a distribution are applied to some illustrative data on four distributions about mental health services. Although these data refer to this one aspect of health, the exercise is of broader relevance than mental health. The summary measures of dispersion conventionally used in empirical work are applied to the data here, such as the standard deviation, the coefficient of variation, the relative mean deviation and the Gini coefficient. Other, less commonly used measures also are applied, such as Theil's Index of Entropy, Atkinson's Measure (using two differing assumptions about the inequality aversion parameter). Lorenz curves are also drawn for these distributions. RESULTS: Distributions are shown to have differing rankings (in terms of which is more equal than another), depending on which measure is applied. CONCLUSION: The scope and content of the literature from the past decade about health inequalities and inequities suggest that the economic literature from the past 100 years about inequality and inequity may have been overlooked, generally speaking, in the health inequalities and inequity literature. An understanding of economic theory and economic method, partly introduced in this article, is helpful in analysing health inequality and inequity

Changes in joint coupling and variability during walking following tibialis posterior muscle fatigue

<p>Abstract</p> <p>Background</p> <p>The tibialis posterior muscle is believed to play a key role in controlling foot mechanics during the stance phase of gait. However, an experiment involving localised tibialis posterior muscle fatigue, and analysis of discrete rearfoot and forefoot kinematic variables, indicated that reduced force output of the tibialis posterior muscle did not alter rearfoot and forefoot motion during gait. Thus, to better understand how muscle fatigue affects foot kinematics and injury potential, the purpose of this study was to reanalyze the data and investigate shank, rearfoot and forefoot joint coupling and coupling variability during walking.</p> <p>Methods</p> <p>Twenty-nine participants underwent an exercise fatigue protocol aimed at reducing the force output of tibialis posterior. An eight camera motion analysis system was used to evaluate 3 D shank and foot joint coupling and coupling variability during treadmill walking both pre- and post-fatigue.</p> <p>Results</p> <p>The fatigue protocol was successful in reducing the maximal isometric force by over 30% and a concomitant increase in coupling motion of the shank in the transverse plane and forefoot in the sagittal and transverse planes relative to frontal plane motion of the rearfoot. In addition, an increase in joint coupling variability was measured between the shank and rearfoot and between the rearfoot and forefoot during the fatigue condition.</p> <p>Conclusions</p> <p>The reduced function of the tibialis posterior muscle following fatigue resulted in a disruption in typical shank and foot joint coupling patterns and an increased variability in joint coupling. These results could help explain tibialis posterior injury aetiology.</p