The female athlete triad in student track and field athletes

Objectives: To explore the female athlete triad components in university track and field athletes, as well as calculate estimated energy availability.Design: Cross-sectional descriptive study design.Setting and subjects: Sixteen volunteer, white, female track and field athletes were recruited from North-West University.Outcome measures: Athletes completed a demographic, health and sport questionnaire; pathogenic body weight control questionnaire; menstrual history questionnaire; four 24-hour dietary recalls and one three-day diet and exercise record form. Body composition and bone mineral density (BMD) were assessed with dual energy X-ray absorptiometry. The bulimia, drive for thinness and body dissatisfaction subscales of the Eating Disorder Inventory, and the cognitive dietary restraint subscale of the Three-Factor Eating Questionnaire, was used to measure disordered eating behaviour. Estimated energy availability was calculated using a three-day dietary and exercise record form completed by the athlete on three heavy training days.Results: In the total group, 25% had menstrual pattern changes, 62.5% disordered eating behaviour, 73.3% (11/15) low estimated energy availability, and 12.5% reported stress fractures during the past two years. The average estimated energy availability was 18.5 (14.1-40.9) kcal/kg fat-free mass/day. Diet or fat-burning pills were the most popular pathogenic weight-control measures used by 37.5% athletes. Athletes with menstrual pattern changes had lower spine [1.043 (0.975-1.059) vs. 1.166 (1.090-1.234) g/cm2, p-value = 0.043] and femoral neck [0.905 ± 0.045 vs. 1.025 ± 0.027 g/cm2, p-value = 0.042) BMD. Altogether, 87.5% athletes presented with various components of.Conclusion: More than two thirds of this group of student track and field athletes had low estimated energy availability and more than three quarters were classified with various combinations of the components of the female athlete triad.Keywords: disordered eating, bone mineral density, energy availability, menstrual cycl

Assessment of the food available to cape anchovy during their spawning season

The Cape anchovy Engraulis capensis spawns serially between September and February each year on the western Agulhas Bank, South Africa. Food availability in terms of copepod biomass is important for successfulspawning and subsequent recruitment. This note investigates the variability within a spawning season (1993/94 and 1994/95) of copepod biomass on the western Bank and demonstrates that the food available to the Capeanchovy cannot be adequately assessed by a single mid-season estimate, as was the previous sampling strategy. The mid-season estimate of food availability failed to reveal important fluctuations, such as the small biomass of copepods in January 1994, which contributed to the early cessation of spawning and subsequent poor recruitment in 1994. A strategy, based on monthly sampling, is recommended for future sampling programmes

A consensus exercise identifying priorities for research into clinical effectiveness among children's orthopaedic surgeons in the United Kingdom

Aims: High-quality clinical research in children’s orthopaedic surgery has lagged behind other surgical subspecialties. This study used a consensus-based approach to identify research priorities for clinical trials in children’s orthopaedics. / Methods: A modified Delphi technique was used, which involved an initial scoping survey, a two-round Delphi process and an expert panel formed of members of the British Society of Children’s Orthopaedic Surgery. The survey was conducted amongst orthopaedic surgeons treating children in the United Kingdom and Ireland. / Results: A total of 86 clinicians contributed to both rounds of the Delphi process, scoring priorities from one (low priority) to five (high priority). Elective topics were ranked higher than those relating to trauma, with the top ten elective research questions scoring higher than the top question for trauma. Ten elective, and five trauma research priorities were identified, with the three highest ranked questions relating to the treatment of slipped capital femoral epiphysis (mean score 4.6/ 5), Perthes’ disease (4.5) and bone infection (4.5). / Conclusion: This consensus-based research agenda will guide surgeons, academics and funders to improve the evidence in children’s orthopaedic surgery and encourage the development of multicentre clinical trials

Four’s a crowd: social preferences for larger groups in golden mantella (Mantella aurantiaca) tadpoles

Group living results in various benefits and costs, which often depend on group size and ontogenetic state of the individual. Therefore, certain group sizes are favourable over others, often depending on individual age or intrinsic state. Under natural conditions many amphibians can be found in aggregations, especially during the larval stage. Yet, whether these aggregations are the result of active social preferences or are driven by environmental factors has only been tested in a limited number of taxa. This study explores social preferences and group size discrimination in golden mantella (Mantella aurantiaca) tadpoles. We gave tadpoles the choice between different numbers of conspecifics using a two-choice design. To test for general social tendency, tadpoles could either join a group of three or remain solitary (3 vs. 0). To test for group size preferences, we tested tadpoles in two different ratios: 2 vs. 1 and 4 vs. 2 conspecifics. We repeated the trials weekly until metamorphosis to determine potential shifts in preference through ontogeny. Tadpoles preferred being with a group over being alone, and the strength of this preference declined with increasing age. Furthermore, tadpoles preferred to be close to the larger of two groups. This preference was stronger in the 2 vs. 1 treatment. Mantella aurantiaca tadpoles, therefore, show clear social tendencies and possess the ability to spontaneously discriminate between group sizes. The lower preference at higher group sizes might indicate cognitive limitations or lower benefits of choosing the larger of two groups when overall group size is high. These findings are one of the few showing social preferences depending on group size in tadpoles and contribute to our understanding of social behaviour in amphibians in general

Lepton Acceleration in Pulsar Wind Nebulae

Pulsar Wind Nebulae (PWNe) act as calorimeters for the relativistic pair winds emanating from within the pulsar light cylinder. Their radiative dissipation in various wavebands is significantly different from that of their pulsar central engines: the broadband spectra of PWNe possess characteristics distinct from those of pulsars, thereby demanding a site of lepton acceleration remote from the pulsar magnetosphere. A principal candidate for this locale is the pulsar wind termination shock, a putatively highly-oblique, ultra-relativistic MHD discontinuity. This paper summarizes key characteristics of relativistic shock acceleration germane to PWNe, using predominantly Monte Carlo simulation techniques that compare well with semi-analytic solutions of the diffusion-convection equation. The array of potential spectral indices for the pair distribution function is explored, defining how these depend critically on the parameters of the turbulent plasma in the shock environs. Injection efficiencies into the acceleration process are also addressed. Informative constraints on the frequency of particle scattering and the level of field turbulence are identified using the multiwavelength observations of selected PWNe. These suggest that the termination shock can be comfortably invoked as a principal injector of energetic leptons into PWNe without resorting to unrealistic properties for the shock layer turbulence or MHD structure.Comment: 19 pages, 5 figures, invited review to appear in Proc. of the inaugural ICREA Workshop on "The High-Energy Emission from Pulsars and their Systems" (2010), eds. N. Rea and D. Torres, (Springer Astrophysics and Space Science series

Using Computer Simulation for Reducing the Appointment Lead-Time in a Public Pediatric Outpatient Department

Pediatric outpatient departments aim to provide a pleasant, effective and continuing care to children. However, a problem in these units is the long waiting time for children to receive an appointment. Prolonged appointment lead-time remains a global challenge since it results in delayed diagnosis and treatment causing increased morbidity and dissatisfaction. Additionally, it leads to an increased number of hospitalization and emergency department visits which augments the financial burden faced by healthcare systems. Despite these considerations, the studies directly concentrating on the reduction of appointment lead-time in these departments are largely limited. Therefore, this paper proposes the application of Discrete-event Simulation (DES) approach to evaluate potential improvement strategies aiming at reducing average appointment lead-time. Initially, the outpatient department is characterized to effectively identify the main activities, process variables, interactions, and system constraints. After data collection, input analysis is conducted through intra-variable independence, homogeneity and goodness-of-fit tests followed by the creation of a simulation model representing the real pediatric outpatient department. Then, Mann-Whitney tests are used to prove whether the model was statistically comparable with the real-world system. After this, the outpatient department performance is assessed in terms of average appointment lead-time and resource utilization. Finally, three improvement scenarios are assessed technically and financially, to determine if they are viable for implementation. A case study of a mixed-patient type environment in a public pediatric outpatient department has been explored to validate the proposed methodology. Statistical tests demonstrate that appointment lead-time in pediatric outpatient departments may be meaningfully minimized using this approach. © 2019, Springer Nature Switzerland AG

Entropy Projection Curved Gabor with Random Forest and SVM for Face Recognition

In this work, we propose a workflow for face recognition under occlusion using the entropy projection from the curved Gabor filter, and create a representative and compact features vector that describes a face. Despite the reduced vector obtained by the entropy projection, it still presents opportunity for further dimensionality reduction. Therefore, we use a Random Forest classifier as an attribute selector, providing a 97% reduction of the original vector while keeping suitable accuracy. A set of experiments using three public image databases: AR Face, Extended Yale B with occlusion and FERET illustrates the proposed methodology, evaluated using the SVM classifier. The results obtained in the experiments show promising results when compared to the available approaches in the literature, obtaining 98.05% accuracy for the complete AR Face, 97.26% for FERET and 81.66% with Yale with 50% occlusion

Subcellular localization of the antidepressant-sensitive norepinephrine transporter

<p>Abstract</p> <p>Background</p> <p>Reuptake of synaptic norepinephrine (NE) via the antidepressant-sensitive NE transporter (NET) supports efficient noradrenergic signaling and presynaptic NE homeostasis. Limited, and somewhat contradictory, information currently describes the axonal transport and localization of NET in neurons.</p> <p>Results</p> <p>We elucidate NET localization in brain and superior cervical ganglion (SCG) neurons, aided by a new NET monoclonal antibody, subcellular immunoisolation techniques and quantitative immunofluorescence approaches. We present evidence that axonal NET extensively colocalizes with syntaxin 1A, and to a limited degree with SCAMP2 and synaptophysin. Intracellular NET in SCG axons and boutons also quantitatively segregates from the vesicular monoamine transporter 2 (VMAT2), findings corroborated by organelle isolation studies. At the surface of SCG boutons, NET resides in both lipid raft and non-lipid raft subdomains and colocalizes with syntaxin 1A.</p> <p>Conclusion</p> <p>Our findings support the hypothesis that SCG NET is segregated prior to transport from the cell body from proteins comprising large dense core vesicles. Once localized to presynaptic boutons, NET does not recycle via VMAT2-positive, small dense core vesicles. Finally, once NET reaches presynaptic plasma membranes, the transporter localizes to syntaxin 1A-rich plasma membrane domains, with a portion found in cholera toxin-demarcated lipid rafts. Our findings indicate that activity-dependent insertion of NET into the SCG plasma membrane derives from vesicles distinct from those that deliver NE. Moreover, NET is localized in presynaptic membranes in a manner that can take advantage of regulatory processes targeting lipid raft subdomains.</p

Proximity curves for potential-based clustering

YesThe concept of proximity curve and a new algorithm are proposed for obtaining clusters in a finite set of data points in the finite dimensional Euclidean space. Each point is endowed with a potential constructed by means of a multi-dimensional Cauchy density, contributing to an overall anisotropic potential function. Guided by the steepest descent algorithm, the data points are successively visited and removed one by one, and at each stage the overall potential is updated and the magnitude of its local gradient is calculated. The result is a finite sequence of tuples, the proximity curve, whose pattern is analysed to give rise to a deterministic clustering. The finite set of all such proximity curves in conjunction with a simulation study of their distribution results in a probabilistic clustering represented by a distribution on the set of dendrograms. A two-dimensional synthetic data set is used to illustrate the proposed potential-based clustering idea. It is shown that the results achieved are plausible since both the ‘geographic distribution’ of data points as well as the ‘topographic features’ imposed by the potential function are well reflected in the suggested clustering. Experiments using the Iris data set are conducted for validation purposes on classification and clustering benchmark data. The results are consistent with the proposed theoretical framework and data properties, and open new approaches and applications to consider data processing from different perspectives and interpret data attributes contribution to patterns