The Family Name as Socio-Cultural Feature and Genetic Metaphor: From Concepts to Methods

A recent workshop entitled The Family Name as Socio-Cultural Feature and Genetic Metaphor: From Concepts to Methods was held in Paris in December 2010, sponsored by the French National Centre for Scientific Research (CNRS) and by the journal Human Biology. This workshop was intended to foster a debate on questions related to the family names and to compare different multidisciplinary approaches involving geneticists, historians, geographers, sociologists and social anthropologists. This collective paper presents a collection of selected communications

Theory of the circular closed loop antenna in the terahertz, infrared, and optical regions

Modern antenna theory forms the bulwark of our knowledge of how radiation and metallic structures interact in the radio frequency (RF) and microwave (MW) regions. The theory has not yet penetrated the terahertz, infrared, and optical regions to the same degree. In this paper, we provide a rigorous analysis of closed circular loop antennas from first principles. Using antenna theory, we tie together their long wavelength behavior with their behavior at short wavelengths through the visible region. We provide analytic forms for the input impedance, current, quality factor, radiation resistance, ohmic loss, and radiation efficiency. We provide an exact circuit model for the closed loop in the RF and MW regions, and extend it through the optical region. We also provide an implicit analytic form for the determination of all modal resonances, allowing prediction of the resonance saturation wavelength for loops. Through simulations, we find that this behavior extends to hexagonal and square loops. All results are applicable to loop circumferences as short as 350 nm. Finally, we provide a precise analytic model of the index of refraction, as a tool in these computations, which works equally well for metals and semi-conductors.This work has been partially supported by the Australian Research Council and the Australian Solar Institute

Maximum Likelihood Estimation for Single Particle, Passive Microrheology Data with Drift

Volume limitations and low yield thresholds of biological fluids have led to widespread use of passive microparticle rheology. The mean-squared-displacement (MSD) statistics of bead position time series (bead paths) are either applied directly to determine the creep compliance [Xu et al (1998)] or transformed to determine dynamic storage and loss moduli [Mason & Weitz (1995)]. A prevalent hurdle arises when there is a non-diffusive experimental drift in the data. Commensurate with the magnitude of drift relative to diffusive mobility, quantified by a P\'eclet number, the MSD statistics are distorted, and thus the path data must be "corrected" for drift. The standard approach is to estimate and subtract the drift from particle paths, and then calculate MSD statistics. We present an alternative, parametric approach using maximum likelihood estimation that simultaneously fits drift and diffusive model parameters from the path data; the MSD statistics (and consequently the compliance and dynamic moduli) then follow directly from the best-fit model. We illustrate and compare both methods on simulated path data over a range of P\'eclet numbers, where exact answers are known. We choose fractional Brownian motion as the numerical model because it affords tunable, sub-diffusive MSD statistics consistent with typical 30 second long, experimental observations of microbeads in several biological fluids. Finally, we apply and compare both methods on data from human bronchial epithelial cell culture mucus.Comment: 29 pages, 12 figure

A new quality of life consultation template for patients with venous leg ulceration

OBJECTIVE: Chronic venous leg ulcers (CVLUs) are common and recurrent, however, care for patients predominantly has a focus which overlooks the impact of the condition on quality of life. The aim of this study was to develop a simple, evidence-based consultation template, with patients and practitioners, which focuses consultations on quality of life themes. METHOD: A nominal group was undertaken to develop a new consultation template for patients with CVLUs based on the findings of earlier qualitative study phases. RESULTS: A user-friendly two-sided A4 template was designed to focus nurse-patient consultations on the quality of life challenges posed by CVLUs. CONCLUSION: CVLUs impact negatively on the quality of life of the patient but this receives inadequate attention during current consultations. This new template will help to ensure that key concerns are effectively raised, explored and addressed during each consultation. DECLARATION OF INTEREST: The NHS West Midlands Strategic Health Authority funded this study. The authors have no conflicts of interest to declare.NHS West Midlands Health Authorit

Asymptotic Analysis of Microtubule-Based Transport by Multiple Identical Molecular Motors

We describe a system of stochastic differential equations (SDEs) which model the interaction between processive molecular motors, such as kinesin and dynein, and the biomolecular cargo they tow as part of microtubule-based intracellular transport. We show that the classical experimental environment fits within a parameter regime which is qualitatively distinct from conditions one expects to find in living cells. Through an asymptotic analysis of our system of SDEs, we develop a means for applying in vitro observations of the nonlinear response by motors to forces induced on the attached cargo to make analytical predictions for two parameter regimes that have thus far eluded direct experimental observation: 1) highly viscous in vivo transport and 2) dynamics when multiple identical motors are attached to the cargo and microtubule

Fingerprinting Soft Materials: A Framework for Characterizing Nonlinear Viscoelasticity

We introduce a comprehensive scheme to physically quantify both viscous and elastic rheological nonlinearities simultaneously, using an imposed large amplitude oscillatory shear (LAOS) strain. The new framework naturally lends a physical interpretation to commonly reported Fourier coefficients of the nonlinear stress response. Additionally, we address the ambiguities inherent in the standard definitions of viscoelastic moduli when extended into the nonlinear regime, and define new measures which reveal behavior that is obscured by conventional techniques.Comment: 10 pages, 3 figures, full-page double-space preprint forma

Repeated sleep-quality assessment and use of sleep-promoting interventions in ICU.

To describe sleep quality using repeated subjective assessment and the ongoing use of sleep-promoting interventions in intensive care. It is well known that the critically ill experience sleep disruption while receiving treatment in the intensive care unit. Both the measurement and promotion of sleep is challenging in the complex environment of intensive care unit. Repeated subjective assessment of patients' sleep in the intensive care unit and use of sleep-promoting interventions has not been widely reported. An observational study was conducted in a 58-bed adult intensive care unit. Sleep quality was assessed using the Richards-Campbell Sleep Questionnaire (RCSQ) each morning. intensive care unit audit sleep-promoting intervention data were compared to data obtained prior to the implementation of a sleep guideline. Patients answered open-ended questions about the facilitators and deterrents of their sleep in intensive care unit. The sample (n = 50) was predominately male (76%) with a mean age: 62.6±16.9 years. Sleep quality was assessed on 2 days or more for 21 patients. The majority of patients (98%) received sleep-promoting interventions. Sleep quality had not improved significantly since the guideline was first implemented. The mean Richards-Campbell Sleep Questionnaire score was 47.9±24.1 mm. The main sleep deterrents were discomfort and noise. Frequently cited facilitators were nothing (i.e. nothing helped) and analgesia. The Richards-Campbell Sleep Questionnaire was used on repeated occasions, and sleep-promoting interventions were used extensively. There was no evidence of improvement in sleep quality since the implementation of a sleep guideline. The use of the Richards-Campbell Sleep Questionnaire for the subjective self-assessment of sleep quality in intensive care unit patients and the implementation of simple-promoting interventions by intensive care unit clinicians is both feasible and may be the most practical way to assess sleep in the intensive care unit context

Renewal reward perspective on linear switching diffusion systems

In many biological systems, the movement of individual agents is commonly characterized as having multiple qualitatively distinct behaviors that arise from various biophysical states. This is true for vesicles in intracellular transport, micro-organisms like bacteria, or animals moving within and responding to their environment. For example, in cells the movement of vesicles, organelles and other cargo are affected by their binding to and unbinding from cytoskeletal filaments such as microtubules through molecular motor proteins. A typical goal of theoretical or numerical analysis of models of such systems is to investigate the effective transport properties and their dependence on model parameters. While the effective velocity of particles undergoing switching diffusion is often easily characterized in terms of the long-time fraction of time that particles spend in each state, the calculation of the effective diffusivity is more complicated because it cannot be expressed simply in terms of a statistical average of the particle transport state at one moment of time. However, it is common that these systems are regenerative, in the sense that they can be decomposed into independent cycles marked by returns to a base state. Using decompositions of this kind, we calculate effective transport properties by computing the moments of the dynamics within each cycle and then applying renewal-reward theory. This method provides a useful alternative large-time analysis to direct homogenization for linear advection-reaction-diffusion partial differential equation models. Moreover, it applies to a general class of semi-Markov processes and certain stochastic differential equations that arise in models of intracellular transport. Applications of the proposed framework are illustrated for case studies such as mRNA transport in developing oocytes and processive cargo movement by teams of motor proteins.Comment: 35 pages, 6 figure