Factors affecting match running performance of elite soccer players: shedding some light on the complexity.

Time-motion analysis is a valuable data-collection technique used to quantify the match running performance of elite soccer players. However, interpreting the reductions in running performance in the second half or temporarily after the most intense period of games is highly complex, as it could be attributed to physical or mental fatigue, pacing strategies, contextual factors or a combination of mutually inclusive factors. Given that research in this domain typically uses a reductionist approach whereby match-running performance is examined in isolation without integrating other factors this ultimately leads to a 1-dimensional insight into match performance. Subsequently, a cohesive review of influencing factors does not yet exist. The aim of this commentary is to provide a detailed insight into the complexity of match running performance and the most influential factors

Limited response of peatland CH4 emissions to abrupt Atlantic Ocean circulation changes in glacial climates

Ice-core records show that abrupt Dansgaard–Oeschger (D–O) climatic warming events of the last glacial period were accompanied by large increases in the atmospheric CH4 concentration (up to 200 ppbv). These abrupt changes are generally regarded as arising from the effects of changes in the Atlantic Ocean meridional overturning circulation and the resultant climatic impact on natural CH4 sources, in particular wetlands. We use two different ecosystem models of wetland CH4 emissions to simulate northern CH4 sources forced with coupled general circulation model simulations of five different time periods during the last glacial to investigate the potential influence of abrupt ocean circulation changes on atmospheric CH4 levels during D–O events. The simulated warming over Greenland of 7–9 °C in the different time periods is at the lower end of the range of 11–15 °C derived from ice cores, but is associated with strong impacts on the hydrological cycle, especially over the North Atlantic and Europe during winter. We find that although the sensitivity of CH4 emissions to the imposed climate varies significantly between the two ecosystem emissions models, the model simulations do not reproduce sufficient emission changes to satisfy ice-core observations of CH4 increases during abrupt events. The inclusion of permafrost physics and peatland carbon cycling in one model (LPJ-WHyMe) increases the climatic sensitivity of CH44 emissions relative to the Sheffield Dynamic Global Vegetation Model (SDGVM) model, which does not incorporate these processes. For equilibrium conditions this additional sensitivity is mostly due to differences in carbon cycle processes, whilst the increased sensitivity to the imposed abrupt warmings is also partly due to the effects of freezing on soil thermodynamics. These results suggest that alternative scenarios of climatic change could be required to explain the abrupt glacial CH4 variations, perhaps with a more dominant role for tropical wetland CH4 sources

Characterization of oxidation mechanisms in a family of polycrystalline chromia-forming nickel-base superalloys

The oxidation properties of a family of novel polycrystalline Ni-based superalloys with varying Ti:Nb ratio have been studied, which has shown a correlation between increasing titanium content and accelerated oxidation kinetics. High-resolution characterization of microstructure and chemistry was carried out on the resultant oxide layers using SEM/EDX and Atom Probe Tomography to precisely locate Ti segregation within chromia scales, in order to identify a potential mechanism to explain this correlation. Despite some spread in the data, levels of Ti dissolved in the chromia oxide scales showed little correlation with the nominal Ti concentration or the oxidation properties of each alloy, indicating that oxidation rates are not reliant on dopant levels within bulk chromia. A number of grain boundaries within the oxide scale were targeted for APT analysis, as these are known to act as short-circuit diffusion paths. Segregation of Ti, Nb and Ta to oxide grain boundaries was observed, suggesting that ion transport rates may instead be mediated by dopants present at grain boundaries rather than dissolved within the bulk

Climate change is an important predictor of extinction risk on macroevolutionary timescales

Anthropogenic climate change is increasing rapidly and already impacting biodiversity. Despite the importance for future projections, understanding of the underlying mechanisms by which climate mediates extinction remains limited. We present an integrated approach examining the role of intrinsic traits vs. extrinsic climate change in mediating extinction risk for marine invertebrates over the past 485 million years. We found that a combination of physiological traits and the magnitude of climate change are necessary to explain marine invertebrate extinction patterns. Our results suggest that taxa previously identified as extinction resistant may still succumb to extinction if the magnitude of climate change is great enough

Let me Google that for you:a time series analysis of seasonality in internet search trends for terms related to foot and ankle pain

BACKGROUND: The analysis of internet search traffic may present the opportunity to gain insights into general trends and patterns in information seeking behaviour related to medical conditions at a population level. For prevalent and widespread problems such as foot and ankle pain, this information has the potential to improve our understanding of seasonality and trends within these conditions and their treatments, and may act as a useful proxy for their true incidence/prevalence characteristics. This study aimed to explore seasonal effects, general trends and relative popularity of internet search terms related to foot and ankle pain over the past decade. METHODS: We used the Google Trends tool to obtain relative search engine traffic for terms relating to foot and ankle pain and common treatments from Google search and affiliated pages for major northern and southern hemisphere English speaking nations. Analysis of overall trends and seasonality including summer/winter differences was carried out on these terms. RESULTS: Searches relating to general foot pain were on average 3.4 times more common than those relating to ankle pain, and twice as common as searches relating to heel pain. Distinct seasonal effects were seen in the northern hemisphere, with large increases in search volumes in the summer months compared to winter for foot (p = 0.004, 95 % CI [22.2–32.1]), ankle (p = 0.0078, 95 % CI [20.9–35.5]), and heel pain (p = 0.004, 95 % CI [29.1–45.6]). These seasonal effects were reflected by data from Australia, with the exception of ankle pain. Annual seasonal effects for treatment options were limited to terms related to foot surgery and ankle orthoses (p = 0.031, 95 % CI [3.5–20.9]; p = 0.004, 95 % CI [7.6–25.2] respectively), again increasing in the summer months. CONCLUSIONS: A number of general trends and annual seasonal effects were found in time series internet search data for terms relating to foot and ankle pain. This data may provide insights into these conditions at population levels. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13047-015-0074-9) contains supplementary material, which is available to authorized users

Predicting Fluid Intelligence of Children using T1-weighted MR Images and a StackNet

In this work, we utilize T1-weighted MR images and StackNet to predict fluid intelligence in adolescents. Our framework includes feature extraction, feature normalization, feature denoising, feature selection, training a StackNet, and predicting fluid intelligence. The extracted feature is the distribution of different brain tissues in different brain parcellation regions. The proposed StackNet consists of three layers and 11 models. Each layer uses the predictions from all previous layers including the input layer. The proposed StackNet is tested on a public benchmark Adolescent Brain Cognitive Development Neurocognitive Prediction Challenge 2019 and achieves a mean squared error of 82.42 on the combined training and validation set with 10-fold cross-validation. In addition, the proposed StackNet also achieves a mean squared error of 94.25 on the testing data. The source code is available on GitHub.Comment: 8 pages, 2 figures, 3 tables, Accepted by MICCAI ABCD-NP Challenge 2019; Added ND

Comparative study of annealed and high temperature grown ITO and AZO films for solar energy applications

We present the optical and electrical properties of ITO and AZO films fabricated directly on silicon substrates under several growth and annealing temperatures, as well as their potential performance when used as low emissivity coatings in hybrid photovoltaic-thermal systems. We use broadband spectroscopic ellipsometry measurements (from 300 nm to 20 μm) to obtain a consistent model for the permittivity of each of the films. The best performance is found using the properties of the ITO film grown at 250 °C, with a state of the art resistivity of 0.2 mΩ-cm and an optimized thickness of 75 nm which leads to an estimated 50% increase in the extracted power compared to a standard diffused silicon solar cell. The Hall mobility and resistivity measurements of all the films are also provided, complementing and supporting the observed optical properties

Constrained evolution drives limited influenza diversity

H3N2 influenza A viruses have been widely circulating in human populations since the pandemic of 1968. A striking feature of the evolutionary development of this strain has been its 'canalized' nature, with narrow evolutionary trees dominated by long trunks with few branching, or bifurcation events and a consequent lack of standing diversity at any single point. This is puzzling, as one might expect that the strong human immune response against the virus would create an environment encouraging more diversity, not less. Previous models have used various assumptions in order to account for this finding. A new analysis published in BMC Biology suggests that this processive evolution down a single path can be recapitulated by a relatively simple model incorporating only two primary parameters - the mutation rate of the virus, and the immunological distance created by each mutation - so long as these parameters are within a particular narrow but biologically plausible range