Investigation on Qingdao, China Public Physical Fitness Activities and Skills

This paper investigates and analyses different groups of people’s physical fitness skills by using literature research and statistical treatment methods. The result of the investigation shows that physical fitness skill is one of the most important elements influencing physical fitness activities. Therefore, this paper suggests China need to perfect the system of community physical instructor, reform physical education in schools and finally improve national physical fitness skills. This paper also provides certain reasons for enhancing national physical fitness activities and the application of “National Fitness Program”.Key words: Fitness Activities; Fitness Skills; Situation;Investigatio

Continuity Enhancement Method for Real-Time PPP Based on Zero-Baseline Constraint of Multi-Receiver

Continuity is one of the metrics that characterize the required navigation performance of global navigation satellite system (GNSS)-based applications. Data outage due to receiver failure is one of the reasons for continuity loss. Although a multi-receiver configuration can maintain position solutions in case a receiver has data outage, the initialization of the receiver will also cause continuous high-precision positioning performance loss. To maintain continuous high-precision positioning performance of real-time precise point positioning (RT-PPP), we proposed a continuity enhancement method for RT-PPP based on zero-baseline constraint of multi-receiver. On the one hand, the mean time to repair (MTTR) of the multi-receiver configuration is improved to maintain continuous position solutions. On the other hand, the zero-baseline constraint of multi-receiver including between-satellite single-differenced (BSSD) ambiguities, zenith troposphere wet delay (ZWD), and their suitable stochastic models are constructed to achieve instantaneous initialization of back-up receiver. Through static and kinematic experiments based on real data, the effectiveness and robustness of proposed method are evaluated comprehensively. The experiment results show that the relationship including BSSD ambiguities and ZWD between receivers can be determined reliably based on zero-baseline constraint, and the instantaneous initialization can be achieved without high-precision positioning continuity loss in the multi-receiver RT-PPP processing

miR-148b-3p affects the pathogenesis of adjuvant-induced arthritis rats through the direct target DNMT1

Our previous study showed that up-regulated DNA methyltransferase-1 (DNMT1) played an important role in the hypermethylation modification of SFRP4 in adjuvant-induced arthritis (AIA) rats. This work focused on the role of disordered miR-148b-3p in RA pathology and its corresponding regulatory targets. The expression of miR-148b-3p and DNMT1, and the effect of miR-148b-3p on the DNMT1 expression were determined by real-time qPCR, western blotting and double luciferase reporter genes. The role of miR-148b-3p on the SFRP4 expression, the canonical Wnt signaling and the pathology of AIA rats was investigated using real-time qPCR, western blotting and methylation-specific PCR (MSP). The results showed that the expression of miR-148b-3p was significantly decreased, the expression of DNMT1 was significantly increased and the DNMT1 was the direct target of miR-148b-3p in AIA rats compared with normal group. Transfection of miR-148b-3p mimics up-regulated the SFRP4 expression, inhibited the canonical Wnt signaling and the pathogenesis of AIA rats by targeting the DNMT1. The role of miR-148b-3p knockdown was opposite to that of miR-148b-3p overexpression. These results suggest that miR-148b-3p may influence the pathogenesis of RA with the DNMT1 as a direct target and miR-148b-3p may be a potential diagnostic and therapeutic target for RA patients

The Initial Performance Evaluation of Mixed Multi-Frequency Undifferenced and Uncombined BDS-2/3 Precise Point Positioning under Urban Environmental Conditions

With the full operation of the global BeiDou navigation satellite system (BDS-3), positioning performance can be further enhanced by BDS-3 combined with the regional BeiDou navigation satellite system (BDS-2). However, due to satellite signals being out of lock and the limited visibility of satellites, the traditional multi-frequency BDS-2/3 precise point positioning (PPP) model is unable to maintain great positioning performance under urban environmental conditions. In this study, a mixed multi-frequency undifferenced and uncombined (UDUC) BDS-2/3 PPP model is presented to improve the positioning performance under urban environmental conditions by making full use of B1I, B1C, B2I, B2a, and B3I signals from all visible BDS satellites. In this model, BDS satellites with single-, dual-, triple- and quad-frequency observations all can participate in PPP. The static and kinematic experiments were carried out using the mixed multi-frequency UDUC BDS-2/3 PPP model to fully assess the positioning performance under urban environmental conditions with comparisons to the multi-frequency model. The static experiments indicated that the mixed multi-frequency UDUC BDS-2/3 PPP could continuously achieve decimeter-level positioning accuracy at a cut-off elevation angle of 40°, but part of the BDS-3 PPP would lose resolution due to limited visible satellites. Furthermore, the initial kinematic vehicle experiment showed that mixed multi-frequency UDUC BDS-2/3 PPP had better satellite geometry and more observation redundancy than the traditional multi-frequency model. Compared with the traditional multi-frequency BDS-2/3 model, the positioning accuracy of the mixed multi-frequency model was improved by 51.6, 35.5, and 39.1%, respectively, in east, north, and up directions. The convergence time was shortened by 40%

pSBMA-Conjugated Magnetic Nanoparticles for Selective IgG Separation

Two types of zwitterionic polymer-modified magnetic nanoparticles (NPs) are fabricated by conjugating pSBMA onto PEI-precoated NPs via either a one-step method (1S NPs) or two-step method (2S NPs). For both methods, divinyl sulfone is used as the linker molecule. Although 1S NPs were capable of resisting both IgG and BSA, 2S NPs exhibited specificity toward IgG adsorption in complex biological fluids, e.g., in a mixture of serums and IgG. The moderate interactions (<i>K</i>_d ≈ 1.2 μM) between IgG and 2S NPs are 3 orders of magnitude lower than IgG binding with protein A (<i>K</i>_d 10 nM). Through complementary characterizations and analyses, we rationalize that the surface developed herein with IgG specificity contains two key components: polyzwitterions with a short chain length and sulfone groups with a high density

Extractive Distillation Approach to the Separation of Styrene from Pyrolysis Gasoline Feedstock Coupled with Deep Desulfurization

The separation of mixtures with close boiling points is a critical task in the petrochemical industry, and one such mixture that requires separation is o-xylene/styrene. The STED process is used to separate o-xylene/styrene, which contains a certain amount of organic sulfur in the product due to the limitations of the process. In this study, the process underwent enhancements to attain the effective separation of styrene and accomplish deep desulfurization. A mixture of sulfolane (SUL) and N-methylpyrrolidone (NMP) was selected as the extraction solvent after calculating the UNIFAC group contributions. An orthogonal experiment was conducted to investigate the effects of the solvent/oil ratio, reflux ratio, water addition rate, and solvent ratio on the product. The correspondence between each factor and the indexes examined was determined, enabling the optimization and prediction of the styrene product quality. The final optimized conditions for the extractive distillation column are as follows: solvent/oil ratio of 7, reflux ratio of 4.5, water addition rate of 6000 kg/h, and a solvent ratio of 9:1. Under optimal conditions, the purity of the product was observed to be greater than that of the original process and the sulfur content of the product can be reduced to lower than 10 ppm at the cost of an increase of 12.31% in energy consumption

Intelligent Molecular Identification for High Performance Organosulfide Capture Using Active Machine Learning Algorithm

Machine learning and computer-aided approaches significantly accelerate molecular design and discovery in scientific and industrial fields increasingly relying on data science for efficiency. The typical method used is supervised learning which needs huge datasets. Semi-supervised machine learning approaches are effective to train unlabeled data with improved modeling performance, whereas they are limited by the accumulation of prediction errors. Here, to screen solvents for removal of methyl mercaptan, a type of organosulfur impurities in natural gas, we constructed a computational framework by integrating molecular similarity search and active learning methods, namely, molecular active selection machine learning (MASML). This new model framework identifies the optimal molecules set by molecular similarity search and iterative addition to the training dataset. Among all 126,068 compounds in the initial dataset, 3 molecules were identified to be promising for methyl mercaptan (MeSH) capture, including benzylamine (BZA), p-methoxybenzylamine (PZM), and N,N-diethyltrimethylenediamine (DEAPA). Further experiments confirmed the effectiveness of our modeling framework in efficient molecular design and identification for capturing methyl mercaptan, in which DEAPA presents a Henry\u27s law constant 89.4% lower than that of methyl diethanolamine (MDEA)