Metallo-Anti-aromatic Al4Na4 and Al4Na3- compounds: A theoretical investigation

We propose a theoretical investigation in this paper to understand the bonding and structural properties of neutral Al4Na4 and anion Al4Na3- clusters. We show that the Al4 species in Al4Na4 and Al4Na3- clusters is a rectangular planar structure with alternate pi-bonds and hence satisfying the basic criteria for anti-aromaticity. We prove that the Al4Na4 and Al4Na3- clusters are metallo-anti-aromatic compounds

Time Series, Stochastic Processes and Completeness of Quantum Theory

Most of physical experiments are usually described as repeated measurements of some random variables. The experimental data registered by on-line computers form time series of outcomes. The frequencies of different outcomes are compared with the probabilities provided by the algorithms of quantum theory (QT). In spite of statistical predictions of QT a claim was made that the theory provided the most complete description of the data and of the underlying physical phenomena. This claim could be easily rejected if some fine structures, averaged out in standard statistical descriptive analysis, were found in the time series of experimental data. To search for these structures one has to use more subtle statistical tools which were developed to study time series produced by various stochastic processes. In this talk we review some of these tools. As an example we show how the standard descriptive statistical analysis of the data is unable to reveal a fine structure in a simulated sample of AR(2) stochastic process. We emphasize once again that the violation of Bell inequalities gives no information on the completeness or the non locality of QT. The appropriate way to test the completeness of quantum theory is to search for fine structures in time series of experimental data by means of the purity tests or by studying the autocorrelation and partial autocorrelation functions.Comment: 7 pages, 3 figures, to be published in AQT Proceedings Vaxjo 2010, AIP Conference Serie

Changes in handgrip force and blood lactate as response to simulated climbing competition

The aim of the study was to estimate post-competition changes in handgrip strength and blood lactate in climbers and relationships of the studied variables with declared climbing ability of the tested athletes. Twenty one male climbers volunteered to take part in the experiment. Each subject took part in simulated lead climbing competition on the artificial wall – (difficulty 7a in French scale). The blood lactate concentration was measured pre-climbing and then 3 min and 30 min post-climbing. Grip force of both hands (dominant and non-dominant) was measured twice – pre-climbing and 1 min post-climbing (semi-final). Maximum heart rate during climbing reached 181.4±7.7 beats per minute. Lactate concentration amounted to 6.35±1.50 mmol/l and 2.28±0.66 mmol/l 3 min and 30 min post-climbing, respectively. Handgrip force related to body mass (averaged for both hands) decreased significantly from 7.39±1.30 N/kg pre-climbing to 6.57±1.05 N/kg 1 min post-climbing. Self reported climbing ability was correlated with lactate concentration and handgrip force, as well. It was demonstrated that athletes reporting higher climbing ability showed better lactate recovery

APPLICATION OF ALLOMETRY FOR DETERMINATION OF STRENGTH PROFILE IN YOUNG FEMALE ATHLETES FROM DIFFERENT SPORTS

The goal of the study was to determine a strength profile in young female athletes practising different sports and to use allometry to evaluate muscular strength with respect to body mass. The study included 42 women who practised taekwondo (n = 10), weightlifting (n = 10), canoeing (n = 14) and speed skating (n = 8). Measurements of maximal muscle torques under static conditions in 10 groups of flexors and extensors of the elbow, shoulder, hip, knee and trunk were carried out. The MANCOVA procedure was employed to compare means between the groups. A logarithm of body mass was adopted as a covariate. Relationships between body mass and muscle torques in each muscle group were determined using a procedure of linear regression. The analysis of residuals was employed for the evaluation of maximal muscle torques. Mean values of logarithms of maximal muscle torques were significantly different for the representatives of individual sports and they depended on the logarithm of body mass. It was proposed to use a mean of residuals normalized for individual muscle groups as a synthetic strength index (mean of the strength profile). The women practising canoeing were characterized by the highest strength index. Its lowest values were obtained by weightlifting and taekwondo athletes. Differences in strength profiles in the tested athletes were attributed to the specific nature of their sports. It is suggested to use an allometric relationship scaled by body mass for strength assessment

Sinus versus nonsinus tachycardia in the emergency department: Importance of age and heart rate

BACKGROUND: The emergency department diagnosis of sinus versus nonsinus tachycardia is an important clinical challenge. The objective of this study was to identify subjects with a high prevalence of nonsinus tachycardia. METHODS: Heart rate and cardiac rhythm were prospective reviewed in 500 consecutive patients with heart rate ≥ 100 beats/min in a busy emergency department. A predictive model based on age and heart rate was then developed to identify the probability of nonsinus tachycardia. RESULTS: As age and heart rate increased, nonsinus tachycardias became more frequent. The probability of nonsinus tachycardia in a subject ≥ 71 years with heart rate ≥ 141 beats/minute was 93%, compared to only three percent in a subject ≤ 50 years with heart rate 100–120 beats/minute. A simple point score system based on age and heart rate helps predict the probability of sinus tachycardia versus nonsinus tachycardia. CONCLUSION: Nonsinus tachycardia is significantly more common than sinus tachycardia in elderly patients in the emergency department. The diagnosis of sinus tachycardia becomes much less likely as age and heart rate increase

Automated Atrial Fibrillation Detection from Electrocardiogram

In this study, a novel Atrial Fibrillation (AFib) detection algorithm is presented based on Electrocardiography (ECG) signals. In particular, the spectrogram of ECG signal is used as an input to a Convolutional Neural Network (CNN) to classify normal and AFib ECG signals. This model is shown to perform well with an accuracy of 92.91% and a value of 0.9789 for the area under the ROC curve (AUC). This study demonstrated the potential of using image classification methods and CNN model to detect abnormal biosignals with noise

Study protocol for a randomised controlled trial evaluating the effect of prenatal omega-3 LCPUFA supplementation to reduce the incidence of preterm birth: The ORIP trial

Introduction: Preterm birth accounts for more than 85% of all perinatal complications and deaths. Seventy-five per cent of early preterm births (EPTBs) occur spontaneously and without identifiable risk factors. The need for a broadly applicable, effective strategy for primary prevention is paramount. Secondary outcomes from the docosahexaenoic acid (DHA) to Optimise Mother Infant Outcome trial showed that maternal supplementation until delivery with omega-3 (ω-3) long chain polyunsaturated fatty acid (LCPUFA), predominantly as DHA, resulted in a 50% reduction in the incidence of EPTB and an increase in the incidence of post-term induction or post-term prelabour caesarean section due to extended gestation. We aim to determine the effectiveness of supplementing the maternal diet with ω-3 LCPUFA until 34 weeks’ gestation on the incidence of EPTB. Methods and analysis: This is a multicentre, parallel group, randomised, blinded and controlled trial. Women less than 20 weeks’ gestation with a singleton or multiple pregnancy and able to give informed consent are eligible to participate. Women will be randomised to receive high DHA fish oil capsules or control capsules without DHA. Capsules will be taken from enrolment until 34 weeks’ gestation. The primary outcome is the incidence of EPTB, defined as delivery before 34 completed weeks’ gestation. Key secondary outcomes include length of gestation, incidence of post-term induction or prelabour caesarean section and spontaneous EPTB. The target sample size is 5540 women (2770 per group), which will provide 85% power to detect an absolute reduction in the incidence of preterm birth of 1.16% (from 2.45% to 1.29%) between the DHA and control group (two sided α=0.05). The primary analysis will be based on the intention-to-treat principle. Trial registration number: Australia and New Zealand Clinical Trial Registry Number: 2613001142729; Pre-results

Subaqueous geomorphology: options, tasks, needs

The purpose of the paper is to present the potentialities of current non-invasive methods for bottom surveys, including cartometric presentation of its relief and structure in both marine and inland reservoirs. The paper presents examples of results obtained in the Maritime Institute in Gdańsk during surveys carried out at the bottom of seas, lakes and rivers with the use of the same apparatus: primarily, a multibeam echosounder (MBES) to obtain a digital terrain model (DTM); a side-scan sonar (SSS) to obtain a general image of the nature of the bottom (its “roughness”); and seismic profiling (sub-bottom profiler, sediment echo sounder [SES]) to recognise the structure of the bottom. The obtained results constitute a necessary basis for carrying out further specialist surveys (non-invasive or invasive) when needed. Current bottom survey options that use MBES, SSS and SES may be treated as subaqueous equivalents of the subaerial potentialities of a land surface survey using LiDaR and GPR (Ground Penetration Radar)