A 2-DIMENSIONAL VIDEO BASED MODEL FOR USE IN ERGOMETER ROWING KINEMATICS

Motion capture of the rowing stroke using accurate 3D opto-reflective systems has been limited by the constraints of the surrounding hydrodynamic environment. As a consequence 2D lower-extremity kinematic models have been used in an attempt to counter these logistical issues (Lamb, 1989). Despite this, there is limited research supporting the accuracy of a 2D video based model (2DVBM) for motion capture of the rowing stroke. The purpose of this study was to assess the accuracy of a 2DVBM against the conventional gait model using a 3D opto-reflective system

THE EFFECT OF CAMERA PAN ON THE TWO-DIMENSIONAL DIRECT LINEAR TRANSFORMATION AND SCALAR RECONSTRUCTION TECHNIQUES WHEN APPLIED TO ERGOMETER ROWING

Changes in camera pan may affect reconstruction accuracy of two-dimensional (2D) kinematic data collected in on-water rowing testing. The 2D direct linear transformation (2D-DLT) may assist in improving reconstruction accuracy of rowing kinematics when a perpendicular camera changes position. Accuracy of the 2D-DLT and scalar reconstruction techniques was compared using coefficient of multiple correlations (CMCs), range of motion difference (ROMDiff) and root mean square error (RMSE). 2DDLT was found to have significantly greater accuracy (CMC and RMSE;

Patterns in hydraulic ripples with binary granular mixtures

An experimental study of a binary granular mixture submitted to a transient shear flow in a cylindrical container is reported. The formation of ripples with a spiral shape is observed. The appearance of phase segregation in those spiral patterns is shown. The relative grain size bewteen sand species is found to be a relevant parameter leading to phase segregation. However, the relative repose angle is an irrelevant parameter. The formation of sedimentary structures is also presented. They result from a ripple climbing process. The ``sub-critical'' or ``super-critical'' character of the lamination patterns is shown to depend on the rotation speed of the container.Comment: 9 pages, 9 figures, LateX (using elsart package), submitted to Phys.

Noninvasive Sphenopalatine Ganglion Block for Acute Headache in the Emergency Department: A Randomized Placebo-Controlled Trial

Study objective We seek to test the efficacy of noninvasive sphenopalatine ganglion block for the treatment of acute anterior headache in the emergency department (ED) using a novel noninvasive delivery device. Methods We conducted a randomized, double-blind, placebo-controlled trial evaluating bupivacaine anesthesia of the sphenopalatine ganglion for acute anterior or global-based headache. This study was completed in 2 large academic EDs. Bupivacaine or normal saline solution was delivered intranasally (0.3 mL per side) with the Tx360 device. Pain and nausea were measured at 0, 5, and 15 minutes by a 100-mm visual analog scale. The primary endpoint was a 50% reduction in pain at 15 minutes. Telephone follow-up assessed 24-hour pain and nausea through a 0- to 10-point verbal scale and adverse effects. Results The median reported baseline pain in the bupivacaine group was 80 mm (IQR 66 mm - 93 mm) and 78.5 mm (IQR 64 mm to 91.75 mm) in the normal saline solution group. A 50% reduction in pain was achieved in 48.8% of the bupivacaine group (20/41 patients) versus 41.3% in the normal saline solution group (19/46 patients), for an absolute risk difference of 7.5% (95% confidence interval [CI] –13% to 27.1%). As a secondary outcome, at 24 hours, more patients in the bupivacaine group were headache free (24.7% difference; 95% CI 2.6% to 43.6%) and more were nausea free (16.9% difference; 95% CI 0.8% to 32.5%). Conclusion For patients with acute anterior headache, sphenopalatine ganglion block with the Tx360 device with bupivacaine did not result in a significant increase in the proportion of patients achieving a greater than or equal to 50% reduction in headache severity at 15 minutes compared with saline solution applied in the same manner

Soil radium, soil gas radon and indoor radon empirical relationships to assist in post-closure impact assessment related to near-surface radioactive waste disposal

Least squares (LS), Theil’s (TS) and weighted total least squares (WTLS) regression analysis methods are used to develop empirical relationships between radium in the ground, radon in soil and radon in dwellings to assist in the post-closure assessment of indoor radon related to near-surface radioactive waste disposal at the Low Level Waste Repository in England. The data sets used are (i) estimated 226Ra in the <2 mm fraction of topsoils (eRa226) derived from equivalent uranium (eU) from airborne gamma spectrometry data, (ii) eRa226 derived from measurements of uranium in soil geochemical samples, (iii) soil gas radon and (iv) indoor radon data. For models comparing indoor radon and (i) eRa226 derived from airborne eU data and (ii) soil gas radon data, some of the geological groupings have significant slopes. For these groupings there is reasonable agreement in slope and intercept between the three regression analysis methods (LS, TS and WTLS). Relationships between radon in dwellings and radium in the ground or radon in soil differ depending on the characteristics of the underlying geological units, with more permeable units having steeper slopes and higher indoor radon concentrations for a given radium or soil gas radon concentration in the ground. The regression models comparing indoor radon with soil gas radon have intercepts close to 5 Bq m−3 whilst the intercepts for those comparing indoor radon with eRa226 from airborne eU vary from about 20 Bq m−3 for a moderately permeable geological unit to about 40 Bq m−3 for highly permeable limestone, implying unrealistically high contributions to indoor radon from sources other than the ground. An intercept value of 5 Bq m−3 is assumed as an appropriate mean value for the UK for sources of indoor radon other than radon from the ground, based on examination of UK data. Comparison with published data used to derive an average indoor radon: soil 226Ra ratio shows that whereas the published data are generally clustered with no obvious correlation, the data from this study have substantially different relationships depending largely on the permeability of the underlying geology. Models for the relatively impermeable geological units plot parallel to the average indoor radon: soil 226Ra model but with lower indoor radon: soil 226Ra ratios, whilst the models for the permeable geological units plot parallel to the average indoor radon: soil 226Ra model but with higher than average indoor radon: soil 226Ra ratios

Assessing Two-Mode Semantic Network Story Representations Using a False Memory Paradigm

This paper describes a novel method of representing semantic networks of stories (and other text) as a two-mode graph. This method has some advantages over traditional one-mode semantic networks, but has the potential drawback (shared with n-gram text networks) that it contains paths that are not present in the text. An empirical study was devised using a false memory paradigm to determine whether these induced paths are remembered as being true of a set of stories. Results indicate that participants report false memories consistent with the induced paths. Implications for further research and two-mode semantic representations are discussed

DO GYMNASTS EXPERIENCE SYMMETRICAL LIMB LOADING WHEN PERFORMING FOUNDATION GYMNASTICS SKILLS?

Uneven asymmetrical landings in artistic gymnastics is considered a risk factor for injury. The aim of this research was to investigate if gymnasts experience asymmetrical upper and lower limb loading when performing foundation gymnastics skills on floor. Sixteen competitive level gymnasts (male= 8, female= 8) performed seven different gymnastics skills while wearing four inertial measurement units located bilaterally on the distal forearm and tibias. Every gymnastics skill showed significant inter-limb asymmetry (range z= -5.8, -6.0,

Midwifery one-to-one support in labour: More than a ratio

Objective: To explore midwifery one-to-one support in labour in a real world context of midwife-led birth environments. Design: Ethnographic study. Data was collected from 30 observations inside and outside the birth environments in three different birth settings. Semi-structured interviews were completed following the births with 29 low-risk women and 30 midwives with at least one year labour support experience to gain their perspectives. Twenty-seven maternity records were also analysed. Setting: An alongside midwife-led unit, freestanding midwife-led unit and women's homes in England. Findings: Six components of care were identified that required balance inside midwife-led birth environments: (1) presence, (2) midwife-woman relationships, (3) coping strategies, (4) labour progress, (5) birthing partners and (6) midwifery support. Midwives used their knowledge, experience and intuitive skills to synchronise their care for the six components to work in balance. Balancing of the six components have been translated into continuums representing the labour care and requirements. Conclusion and implications for practice: Midwifery one-to-one support in labour is more than a ratio when translated into clinical practice. When the balance of the six components were tuned into the needs of women, women were satisfied with their labour and birth experience, even when it did not go to plan. A one midwife to one woman ratio should be available for all women in labour

Consequences of non-random species loss for decomposition dynamics: experimental evidence for additive and non-additive effects

1.   Although litter decomposition is a fundamental ecological process, most of our understanding comes from studies of single-species decay. Recently, litter-mixing studies have tested whether monoculture data can be applied to mixed-litter systems. These studies have mainly attempted to detect non-additive effects of litter mixing, which address potential consequences of random species loss – the focus is not on which species are lost, but the decline in diversity per se . 2.   Under global change, species loss is likely to be non-random, with some species more vulnerable to extinction than others. Under such scenarios, the effects of individual species (additivity) as well as of species interactions (non-additivity) on decomposition rates are of interest. 3.   To examine potential impacts of non-random species loss on ecosystems, we studied additive and non-additive effects of litter mixing on decomposition. A full-factorial litterbag experiment was conducted using four deciduous leaf species, from which mass loss and nitrogen content were measured. Data were analysed using a statistical approach that first looks for additive identity effects based on the presence or absence of species and then significant species interactions occurring beyond those. It partitions non-additive effects into those caused by richness and/or composition. 4.   This approach addresses questions key to understanding the potential effects of species loss on ecosystem processes. If additive effects dominate, the consequences for decomposition dynamics will be predictable based on our knowledge of individual species, but not statistically predictable if non-additive effects dominate. 5.   We found additive (identity) effects on mass loss and non-additive (composition) effects on litter nitrogen dynamics, suggesting that non-random species loss could significantly affect this system. We were able to identify the species responsible for effects that would otherwise have been considered idiosyncratic or absent when analysed by the methods used in previous work. 6.   Synthesis . We observed both additive and non-additive effects of litter-mixing on decomposition, indicating consequences of non-random species loss. To predict the consequences of global change for ecosystem functioning, studies should examine the effects of both random and non-random species loss, which will help identify the mechanisms that influence the response of ecosystems to environmental change.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73943/1/j.1365-2745.2007.01346.x.pd

Design of quadrature rules for Müntz and Müntz-logarithmic polynomials using monomial transformation

A method for constructing the exact quadratures for Müntz and Müntz-logarithmic polynomials is presented. The algorithm does permit to anticipate the precision (machine precision) of the numerical integration of Müntz-logarithmic polynomials in terms of the number of Gauss-Legendre (GL) quadrature samples and monomial transformation order. To investigate in depth the properties of classical GL quadrature, we present new optimal asymptotic estimates for the remainder. In boundary element integrals this quadrature rule can be applied to evaluate singular functions with end-point singularity, singular kernel as well as smooth functions. The method is numerically stable, efficient, easy to be implemented. The rule has been fully tested and several numerical examples are included. The proposed quadrature method is more efficient in run-time evaluation than the existing methods for Müntz polynomial