34 research outputs found

    Hair Whorls and Monozygosity

    Get PDF

    Precise characterization of nanometer-scale systems using interferometric scattering microscopy and Bayesian analysis

    Full text link
    Interferometric scattering microscopy (iSCAT) can image the dynamics of nanometer-scale systems. The typical approach to analyzing interferometric images involves intensive processing, which discards data and limits the precision of measurements. We demonstrate an alternative approach: modeling the interferometric point spread function (iPSF) and fitting this model to data within a Bayesian framework. This approach yields best-fit parameters, including the particle's three-dimensional position and polarizability, as well as uncertainties and correlations between these parameters. Building on recent work, we develop a model that is parameterized for rapid fitting. The model is designed to work with Hamiltonian Monte Carlo techniques that leverage automatic differentiation. We validate this approach by fitting the model to interferometric images of colloidal nanoparticles. We apply the method to track a diffusing particle in three dimensions, to directly infer the diffusion coefficient of a nanoparticle without calculating a mean-square displacement, and to quantify the ejection of DNA from an individual lambda phage virus, demonstrating that the approach can be used to infer both static and dynamic properties of nanoscale systems

    The Health Informatics Trial Enhancement Project (HITE): Using routinely collected primary care data to identify potential participants for a depression trial

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Recruitment to clinical trials can be challenging. We identified anonymous potential participants to an existing pragmatic randomised controlled depression trial to assess the feasibility of using routinely collected data to identify potential trial participants. We discuss the strengths and limitations of this approach, assess its potential value, report challenges and ethical issues encountered.</p> <p>Methods</p> <p>Swansea University's Health Information Research Unit's Secure Anonymised Information Linkage (SAIL) database of routinely collected health records was interrogated, using Structured Query Language (SQL). Read codes were used to create an algorithm of inclusion/exclusion criteria with which to identify suitable anonymous participants. Two independent clinicians rated the eligibility of the potential participants' identified. Inter-rater reliability was assessed using the kappa statistic and inter-class correlation.</p> <p>Results</p> <p>The study population (N = 37263) comprised all adults registered at five general practices in Swansea UK. Using the algorithm 867 anonymous potential participants were identified. The sensitivity and specificity results > 0.9 suggested a high degree of accuracy from the algorithm. The inter-rater reliability results indicated strong agreement between the confirming raters. The Intra Class Correlation Coefficient (Cronbach's Alpha) > 0.9, suggested excellent agreement and Kappa coefficient > 0.8; almost perfect agreement.</p> <p>Conclusions</p> <p>This proof of concept study showed that routinely collected primary care data can be used to identify potential participants for a pragmatic randomised controlled trial of folate augmentation of antidepressant therapy for the treatment of depression. Further work will be needed to assess generalisability to other conditions and settings and the inclusion of this approach to support Electronic Enhanced Recruitment (EER).</p

    End of organised atheism. The genealogy of the law on freedom of conscience and its conceptual effects in Russia

    Get PDF
    In the current climate of the perceived alliance between the Russian Orthodox Church and the state, atheist activists in Moscow share a sense of juridical marginality that they seek to mitigate through claims to equal rights between believers and atheists under the Russian law on freedom of conscience. In their demands for their constitutional rights, including the right to political critique, atheist activists come across as figures of dissent at risk of the state's persecution. Their experiences constitute a remarkable (and unexamined in anthropology) reversal of political and ideological primacy of state-sponsored atheism during the Soviet days. To illuminate the legal context of the atheists’ current predicament, the article traces an alternative genealogy of the Russian law on freedom of conscience from the inception of the Soviet state through the law's post-Soviet reforms. The article shows that the legal reforms have paved the way for practical changes to the privileged legal status of organized atheism and brought about implicit conceptual effects that sideline the Soviet meaning of freedom of conscience as freedom from religion and obscure historical references to conscience as an atheist tenet of Soviet ethics

    Age Estimation on Two Mediterranean Populations Using Rib Histomorphology

    No full text
    One of the crucial steps for the creation of the biological profile of an individual is the estimation of age at death. The choice of the method depends on the nature of the remains, the equipment available and the expertise of the forensic anthropologist, among others. In cases of very fragmented remains, microscopic methods remain one of the only approaches that can be applied. This study presents the results obtained from a histological analysis of rib thin-sections from two Mediterranean populations. The sample consists of 88 standard ribs from two Modern samples (Cretan and Greek-Cypriot Collections, N=88, Mean age=60, SD=17.90). The costal elements were processed histologically according to standard protocols. Thirteen variables (both qualitative and quantitative parameters) were assessed. Technical Error Measurement (TEM) analysis was performed to test the repeatability of the histological parameters. A validation study was performed by applying four existing microscopic methods to verify whether a formula is required for the sample at hand. The correlation between the variables and age was examined through different statistical approaches. The results were used for the generation of linear models using the whole sample and the sample divided by sexes and populations. Intra- and inter-observer errors demonstrated that the variables presented different levels of agreement. Three out of four of the methods exhibited a systematic underestimation of the individuals producing high error rates. Most of the variables demonstrated a significant correlation with age and some differences were observed between sexes and samples (Cretans and Greek-Cypriots). A total of 41 models were generated and 12 were selected as the most accurate with a standard error of the estimate ranging from 12 to 8 years. A comparison between the Mediterranean samples and other populations exhibited different patterns on bone remodeling, with the Cretan sample having the lowest Osteon Population Density (OPD) among others. This research demonstrates the use of quantitative histology for the estimation of age at death, producing accuracy rates similar to those provided by macroscopic methods. The poor results obtained by the existing histological formulas confirmed the need for a population-specific equation for Cretans and Cypriots. Possible intrinsic and extrinsic factors may be the cause of the observed inter-population variation, with differences in nutrition and genetics being considered as the potential causes. Thus, interesting patterns on remodeling rates provided a new insight on bone histological parameters for the sample under study

    Additional file 2 of Sociodemographic differences in 24-hour time-use behaviours in New Zealand children

    No full text
    Additional file 2: Supplemental Figure S1. Ternary plots showing the difference between gender, for activity intensity (top) and activity type (bottom). The small points represent individual participants, the large points and crosshairs represent the compositional means for each group, while the polygon indicates the 95% confidence ellipse. The axis units are proportions (%) of time. Supplemental Figure S2. Ternary plots showing the difference among ethnicities, for activity intensity (top) and activity type (bottom). The small points represent individual participants, the large points and crosshairs represent the compositional means for each group, while the polygon indicates the 95% confidence ellipse. The axis units are proportions (%) of time. Supplemental Figure S3. Ternary plots showing the difference among household income groups, for activity intensity (top) and activity type (bottom). The small points represent individual participants, the large points and crosshairs represent the compositional means for each group, while the polygon indicates the 95% confidence ellipse. The axis units are proportions (%) of time
    corecore