α8β1 integrin regulates nutrient absorption through an Mfge8-PTEN dependent mechanism.

Coordinated gastrointestinal smooth muscle contraction is critical for proper nutrient absorption and is altered in a number of medical disorders. In this work, we demonstrate a critical role for the RGD-binding integrin α8β1 in promoting nutrient absorption through regulation of gastrointestinal motility. Smooth muscle-specific deletion and antibody blockade of α8 in mice result in enhanced gastric antral smooth muscle contraction, more rapid gastric emptying, and more rapid transit of food through the small intestine leading to malabsorption of dietary fats and carbohydrates as well as protection from weight gain in a diet-induced model of obesity. Mechanistically, ligation of α8β1 by the milk protein Mfge8 reduces antral smooth muscle contractile force by preventing RhoA activation through a PTEN-dependent mechanism. Collectively, our results identify a role for α8β1 in regulating gastrointestinal motility and identify α8 as a potential target for disorders characterized by hypo- or hyper-motility

Development of Rockburst Research: A Comprehensive Review

Rockburst is a difficult problem in underground resource development and infrastructure construction. With scientific and technological progress, more research technologies and methods to prevent rockburst have been proposed and applied. Research content has become more comprehensive, and positive progress and achievements have been made. However, due to the complexity of rockburst control factors and the sudden occurrence of rockburst, the occurrence mechanism and accurate prediction of occurrence intensity and time are still difficult worldwide problems. In this paper, the research development and achievements of rockburst are reviewed. Firstly, various definitions and types of rockburst are briefly summarized. Then, research progress and achievements in four aspects are comprehensively reviewed, including methods and techniques of rockburst research (theoretical research, numerical simulation, physical model tests and in situ monitoring), mechanism of rockburst, classification and prediction of rockburst (empirical criteria, in situ monitoring, mathematical model approaches and rockburst chart) and prevention and control of rockburst. Of particular significance is that the classification and prediction with prevention and control are summarized in detail. Finally, limitations, deficiencies and some promising directions for future research are listed

Studies of gas-liquid two-phase flows in horizontal mini tubes using 3D reconstruction and numerical methods

In order to study the characteristics of 3D gas-liquid interfaces, flow pattern transitions, and void fraction in mini tubes, virtual multi-vision experiments and numerical simulations are conducted in a 5.16 mm horizontal tube with air as the dispersed phase and water as the continuous phase. Air and water flow velocities range from 0.024 to 12.330 m/s and from 0.039 to 0.942 m/s, respectively. A simple setup is adopted to capture images synchronously from two orthogonal views with a prism. 3D gas-liquid interfaces of bubbly, slug, and annular flows in horizontal mini tubes are reconstructed in Matlab based on the captured images. Flow pattern transitions and void fractions with 3D interfaces are comprehensively investigated both experimentally and numerically. The numerical results fit well with experimental data in terms of 3D interfaces, cross-sectional and volumetric void fractions. The results show that three flow patterns (bubbly, slug, and annular) are observed experimentally and numerically. The increases in both bubble size and interfacial fluctuation are the main reasons for flow pattern transitions. Two peaks are observed in the Probability Density Functions figures for intermittent flows, while only one peak is obtained for annular flow. The volumetric void fraction fits well with the homogenous model when the gas quality is lower than 0.8, while the slip ratio is around 1. The velocity difference between the two phases increases dramatically at a higher gas quality, leading to a lower void fraction than the predicted value by the homogenous model. The results agree well with empirical correlations with a mean average deviation about 10%, which validates the experimental and numerical methods in the present work

EMD-GM-ARMA Model for Mining Safety Production Situation Prediction

In order to improve the prediction accuracy of mining safety production situation and remove the difficulty of model selection for nonstationary time series, a grey (GM) autoregressive moving average (ARMA) model based on the empirical mode decomposition (EMD) is proposed. First of all, according to the nonstationary characteristics of the mining safety accident time series, nonstationary original time series were decomposed into high- and low-frequency signals using the EMD algorithm, which represents the overall trend and random disturbances, respectively. Subsequently, the GM model was used to predict high-frequency signal sequence, while the ARMA model was used to predict low-frequency signal sequence. Finally, aiming to predict the mining safety production situation, the EMD-GM-ARMA model was constructed via superimposing the prediction results of each subsequence, thereby compared to the ARIMA model, wavelet neural network model, and PSO-SVM model. The results demonstrated that the EMD-GM-ARMA model and the PSO-SVM model hold the highest prediction accuracy in the short-term prediction, and the wavelet neural network has the lowest prediction accuracy. The PSO-SVM model’s prediction accuracy decreases in medium- and long-term predictions while the EMD-GM-ARMA model still can maintain high prediction accuracy. Moreover, the relative error fluctuations of the EMD-GM-ARMA model are relatively stable in both short-term and medium-term predictions. This shows that the EMD-GM-ARMA model can provide high-precision predictions with high stability, proving the model to be feasible and effective in predicting the mining safety production situation

Additional file 1: of Neoadjuvant everolimus plus letrozole versus fluorouracil, epirubicin and cyclophosphamide for ER-positive, HER2-negative breast cancer: study protocol for a randomized pilot trial

SPIRIT Checklist. Checklist of the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) guidelines. (DOCX 49 kb