Abstract
The default mode network (DMN) plays an important role in age-related cognitive decline. This study aims to explore the modulation effect of two mind–body interventions (Tai Chi Chuan and ...Baduanjin) on DMN in elderly individuals. Participants between 50 and 70 years old were recruited and randomized into a Tai Chi Chuan, Baduanjin or control group. The Wechsler Memory Scale-Chinese Revision and resting-state fMRI scans were administered at baseline and following 12 weeks of exercise. Seed-based resting-state functional connectivity (rsFC) was calculated. We found that (i) compared to the Baduanjin group, Tai Chi Chuan was significantly associated with increased rsFC between the medial prefrontal cortex (mPFC) and right putamen/caudate and (ii) compared to the control group, Tai Chi Chuan increased posterior cingulate cortex rsFC with the right putamen/caudate, while Baduanjin decreased rsFC between the mPFC and orbital prefrontal gyrus/putamen. Baseline mPFC rsFC with orbital prefrontal gyrus was negatively correlated with visual reproduction subscore. These results suggest that both Tai Chi Chuan and Baduanjin can modulate the DMN, but through different pathways. Elucidating the mechanisms underlying different mind–body interventions may shed light on the development of new methods to prevent age-related diseases as well as other disorders associated with disrupted DMN.
We report the structure, magnetic and electrical/thermal transport properties of the antiferromagnet MnSn2. Importantly, the existence of the two antiferromagnetic states below TN2 (∼320 K) is ...confirmed by magnetism and electrical transport measurements. An unsaturated positive magnetoresistance up to 150% at ∼9 T was observed at 5 K, whereas the magnetoresistance becomes negative in the whole range at high temperatures (T > 74 K). Systematic investigations of the Hall transport and thermoelectric properties reveal that the hole-type carriers are the majority carriers in MnSn2. The kink around 320 K in the Seebeck coefficient originates from the effect of the antiferromagnetic phase on the band structure, while the pronounced peak around 231 K is attributed to the phonon-drag effect. The results suggest that the spin arrangement plays a vital role in the magnetic, electrical, and thermal transport properties in MnSn2.
Tai Chi Chuan was used for stroke survivors with balance impairments. However, even a short-form of Tai Chi Chuan includes forms that make the exercise challenging for the stroke survivors. Tai Chi ...Yunshou (wave hands in the cloud) is the "mother" form and the fundamental form of all Tai Chi Chuan styles, which is considered more suitable and feasible for stroke survivors with balance impairments. So this study was designed to evaluate the effects of Tai Chi Yunshou exercise on community-based stroke patients with balance dysfunctions.
A total of 250 participants from 10 community health centers (5 per arm) were selected and randomly allocated into Tai Chi Yunshou exercise group (TC group) or a balance rehabilitation training group (control group) in an equal ratio. Participants in the TC group were received Tai Chi Yunshou exercise training five times per week for 12 weeks and those in control group were received balance rehabilitation training five times per week for 12 weeks. Outcome assessments including Berg Balance Scale (BBS), Time up to go test (TUGT), Modified Barthel Index (MBI) were measured at baseline, 4 weeks, 8 weeks, 12 weeks and followed-up 6 weeks (18 weeks), 12 weeks (24 weeks). Intention-to-treat analysis was performed. Analysis of variance of repeated measures was used to assess between-group differences.
A total of 244 participants, 120 in the TC group and 124 in the rehabilitation group, were included in final analysis. There was no siginificant difference in Tai Chi Yunshou and balance rehabilitation training on the improvement of balance ability and mobility (
= 0.531 and
= 0.839, respectively) after adjustment for baseline. However, there was significant difference between two groups on improvement of motor funtion (
= 0.022), fear of falling (
< 0.001) and depression (
= 0.035) for the post stroke patients. No adverse events were reported during the study.
Tai Chi Yunshou and balance rehabilitation training led to improved balance ability and functional mobility, and both are suitable community-based programs that may benefit for stroke recovery and community reintegration. Our data demonstrated that a 12-week Tai Chi Yunshou intervention was more effective in motor function, fear of falling and depression than balance rehabilitation training. Future studies examining the effectiveness of Tai Chi Yunahou as a balance ability improvement strategy for community-dwelling survivors of stroke are recommended.
Chinese Clinical Trail Registry: ChiCRT-TRC-13003641. Registration date: 22 August, 2013.
The frequent occurrence of price cheating on remanufactured products has seriously affected the healthy development of remanufactured products market. And there are many uncertainties in society that ...greatly affect the behavioral decisions of market participants. Therefore, it is necessary to study the price cheating of remanufactured products under random interference. Firstly, we introduce Gaussian white noise as random interference and construct a stochastic evolutionary game of sellers, consumers and the government. Secondly, we analyze stability conditions of the system by using the stability discriminant theorem for stochastic differential equation. Finally, we numerically solve the model using Milstein method and perform numerical simulations to analyze the factors affecting evolutionary paths of the system. Some important results are obtained. i) Decisions of sellers, consumers and the government fluctuate up and down by random interference. The greater the intensity of random interference is, the greater the fluctuations of decisions are. ii) Under same conditions, sellers are the fastest to evolve to choose not to disguise, the government is the second fastest to evolve to choose not to strictly inspect, and consumers are the slowest to evolve to choose green consumption. iii) Increasing consumer acceptance of remanufactured products, consumers' willingness to pay for remanufactured products, and consumer discrimination can prompt sellers to choose not to disguise.
It is of great significance to analyze and predict the trend of crude oil price for international political pattern and economic development. Considering the nonlinear and non-stationary ...characteristics of crude oil price, this paper proposes an interval prediction model of crude oil spot price driven by data characteristics. Firstly, to separate the complex features in the sequences, the crude oil price interval sequences and sequences of the variables with the predictive ability to the crude oil price were decomposed simultaneously by multiple empirical mode decomposition method. Secondly, the sequences were reconstructed into two subsequences of low-frequency and high- frequency respectively according to the complexity of the sequence after decomposition. Then, autoregressive integrated moving average model with input variables and multiple support vector regression model were used to predict the low-frequency and high- frequency subsequences of reconstructed crude oil prices respectively. Finally, the results of the two parts are linear integrated to get the interval forecast results. The empirical results show that the performance of the proposed model is better than the selected comparison model, which can provide some reference value for relevant decision-makers.
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•The domain-averaged PM2.5 in North China decreased significantly from 2013 to 2017.•Firstly established two automatic algorithms to identify regional pollution types and events.•The ...relationships of synoptic circulations and regional PM2.5 levels were quantified.•Starting areas, synoptic and local meteorological mechanisms were analyzed based on persistent regional pollution events.•Quantifying the effects of weather changes on the interannual PM2.5 variations.
In the last decade, North China (NC) has been one of the most populated and polluted regions in the world. The regional air pollution has had a serious impact on people’s health; thus, all levels of government have implemented various pollution prevention measures since 2013. Based on multi-city in situ environmental and meteorological data, as well as the meteorological reanalysis dataset from 2013 to 2017, regional pollution characteristics and meteorological formation mechanisms were analyzed to provide a more comprehensive understanding of the evolution of PM2.5 in NC. The domain-averaged PM2.5 was 79 ± 17 µg m−3 from 2013 to 2017, with a decreasing rate of 10 μg m−3 yr−1. Two automatic computer algorithms were established to identify 6 daily regional pollution types (DRPTs) and 48 persistent regional pollution events (PRPEs) over NC during 2014–2017. The average PM2.5 concentration for the Large-Region-Pollution type (including the Large-Moderate-Region-Pollution and Large-Severe-Region-Pollution types) was 113 ± 40 µg m−3, and more than half of Large-Region-Pollution days and PRPEs occurred in winter. The PRPEs in NC mainly developed from the area south of Hebei. The number of Large-Region-Pollution days decreased notably from 2014 to 2017, the annual number of days varying between 194 and 97 days, whereas a slight decline was observed in winter. In addition, the averaged PM2.5 concentrations and the numbers and durations of the PRPEs decreased. Lamb-Jenkinson weather typing was used to reveal the impact of synoptic circulations on PM2.5 across NC. Generally, the contributions of the variations in circulation to the reduction in PM2.5 levels over NC between 2013 and 2017 were 64% and 45% in summer and winter, respectively. The three most highly polluted weather types were types C, S and E, with an average PM2.5 concentration of 137 ± 40 µg m−3 in winter. Furthermore, three typical circulation dynamics were categorized in the peak stage of the PRPEs, namely, the southerly airflow pattern, the northerly airflow pattern and anticyclone pattern; the averaged relative humidity, recirculation index, wind speed and boundary layer height were 63%, 0.33, 2.0 m s−1 and 493 m, respectively. Our results imply that additional emission reduction measures should be implemented under unfavorable meteorological situations to attain ambient air quality standards in the future.
The biggest challenge to recommendation systems based on user preferences is how to improve the ability of the recommendation system to mine and analyse user preferences and behaviours. In this ...process, we must not only consider the continuation of the user's long-term preference but also improve the system's ability to accommodate short-term preferences and discrete preferences. To this end, we focus on the performance of time factors of user preferences. However, the issue we are concerned about has not received much attention in the existing research. We propose a new recommendation model based on the perspective of user sessions, namely GACOforRec. This model can handle long-term and stable preferences at the same time and preserve the hierarchy of potential preferences. We conducted a large number of comparative experiments on two real datasets, and the results show that GACOforRec is significantly better than other state-of-the-art methods in the study of user sessions.
•Stainless steel bipolar plates with square mesh flow field (SMFF) and obstruction mesh flow field (OMFF) structures were designed.•Stainless steel bipolar plates with square mesh flow field (SMFF) ...and obstruction mesh flow field (OMFF) structures were fabricated by selective laser melting (SLM).•The SMFF and the OMFF bipolar plates were assembled into single cells and polarization experiments were carried out•The current density distribution, gas velocity distribution and water distribution in the SMFF and the OMFF fuel cells were revealed by Computational Fluid Dynamics (CFD).
The bipolar plate is a key component of the proton exchange membrane fuel cell (PEMFC), as it connects each cell electrically, supplies reactant gases to both the anode and the cathode, and removes reaction products from the cell. In this work, stainless steel bipolar plates with different flow field structures were prepared by the selective laser melting (SLM) technique, and assembled into a single PEMFC to implement the polarization test. Finally, the operating parameters of CFD multiphase flow numerical simulation were set. The differences of current density distribution, gas diffusion characteristics and water distribution characteristics of different flow field structures and their influences on the performance of PEMFC were analyzed. Results show that the bipolar plates prepared by the SLM technology show high forming quality. The square mesh flow field (SMFF) is superior to the obstruction mesh flow field (OMFF). The power density of SMFF reaches 387.9 mW cm−2 at 0.3 V, which is ∼30% higher than OMFF. The gas and water distribution of SMFF is more uniform, and the electrical conductivity is higher, reducing its ohmic loss, and improving the output performance of PEMFC.
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Asthma is one of the common chronic respiratory diseases in children, which poses a serious threat to children's quality of life. Respiratory infection is a risk factor for asthma. Compared with ...healthy children, children with early respiratory infections have a higher risk of asthma and an increased chance of developing severe asthma. Many clinical studies have confirmed the correlation between respiratory infections and the pathogenesis of asthma, but the underlying mechanism is still unclear. The gut microbiome is an important part of maintaining the body's immune homeostasis. The imbalance of the gut microbiome can affect the lung immune function, and then affect lung health and cause respiratory diseases. A large number of evidence supports that there is a bidirectional regulation between intestinal flora and respiratory tract infection, and both are significantly related to the development of asthma. The changes of intestinal microbial components and their metabolites in respiratory tract infection may affect the occurrence and development of asthma through the immune pathway. By summarizing the latest advancements in research, this review aims to elucidate the intricate connection between respiratory tract infections and the progression of asthma by highlighting its bridging role of the gut microbiome. Furthermore, it offers novel perspectives and ideas for future investigations into the mechanisms that underlie the relationship between respiratory tract infections and asthma.
It is beneficial to use user review as a preference expression because they contain information that is not in the interaction record. However, most current research on recommendation systems only ...models the explicit records of users and items. It does not mine more personalized information from the review texts generated simultaneously with the interaction records. In this article, we proposed a heterogeneous fusion recommendation model for extracting fine-grained product attributes and user behavior from the review texts. The model we proposed is called TextOG. In the first half of the model, we used two blocks to learn user reviews and item reviews, one of which is dedicated to learning user behavior using reviews written by users, and the other block determines product attributes from reviews written for products. In the second half of the model, we connected the latent factors learned by users and items to perform spatial convolution on the graph. That way, implicit features can perform complex interactions in non-Euclidean spaces. We conducted experiments on a large review data set, and the results show that TextOG performs better than the baseline recommendation methods on various datasets.
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