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This cross-sectional study aimed to explore the characteristics of cellphone use in Chinese early adolescents and the moderating and mediating role of self-control in the relationships among sedentary behavior, physical exercise, and cellphone use time. Using convenience sampling, we selected eight middle schools in Guangzhou, China. Two classes in the first grade of each middle school were randomly selected as the survey subjects. A total of 715 early adolescents (ages 11–13) completed surveys about the purpose of using cellphones (i.e., learning, entertainment, and others), cellphone use scenarios (i.e., sitting, standing, and moving), sedentary behavior, physical exercise, cellphone use time, and self-control. The results showed that the mean total daily cellphone use was 36.44 ± 37.42 min/day in early adolescents, who used cellphones mainly for studying, and 91.7% of them were seated when using cellphones. Cellphone use time was positively correlated with sedentary behavior, not correlated with physical exercise, and negatively correlated with self-control. Self-control played a moderating (not mediating) role not only between sedentary behavior and cellphone use time but also between physical exercise and cellphone use time. This study revealed the complex relationships among sedentary behavior, physical exercise, self-control, and cellphone use time. Our findings have significance for preventing the overuse of cellphones among early adolescents.

Objectives The aims of this study were to use functional near-infrared spectroscopy (fNIRS) to determine whether cardiovascular fitness levels modulate the activation of the mirror neuron system (MNS) under table-setting tasks in non-exercise situation, to replicate the study that positive effect of acute moderate-intensity exercise on the MNS and investigate whether cardiovascular fitness levels modulates the effect of exercise on the activation of the MNS. Methods Thirty-six healthy college-aged participants completed a maximal graded exercise test (GXT) and were categorized as high, moderate, or low cardiovascular fitness. Participants then performed table-setting tasks including an action execution task (EXEC) and action observation task (OBS) prior to (PRE) and after (POST) either a rest condition (CTRL) or a cycling exercise condition (EXP). The EXP condition consisted of a 5-min warm-up, 15-min moderate-intensity exercise (65% VO2 max), and 5-min cool-down. Results No significant differences were observed for Oxy-Hb and Deoxy-Hb between different cardiovascular fitness levels in the EXEC or OBS tasks in the non-exercise session. But there were significant improvements of oxygenated hemoglobin (Oxy-Hb) in the inferior frontal gyrus (IFG) and pre-motor area (PMC) regions under the OBS task following the acute moderate exercise. Particularly, the improvements (Post-Pre) of Δ Oxy-Hb were mainly observed in high and low fitness individuals. There was also a significant improvement of deoxygenated hemoglobin (Deoxy-Hb) in the IPL region under the OBS task. The following analysis indicated that exercise improved Δ Deoxy-Hb in high fitness individuals. Conclusion This study indicated that the activation of MNS was not modulated by the cardiovascular fitness levels in the non-exercise situation. We replicated the previous study that moderate exercise improved activation of MNS; we also provided the first empirical evidence that moderate-intensity exercise positively affects the MNS activation in college students of high and low cardiovascular fitness levels.

The synthesis of β-keto lactone was completed using cyclohexanone as starting material. The α,β-unsaturated lactone was obtained through Reformatsky reaction and iodolactonization. The aforementioned lactone was converted into target compound (β-keto lactone) by Nef oxidation and Claisen condensation in six steps with 17.9% overall yield.

Under the experimental conditions, , specific PCR can can quickly and accurately separate the Streptococcus thermophilus from three categories of dairy products, 14.kinds of dairy products,Both primers CR1 and CR2 optimal annealing temperature was 58.0 °C, annealing temperature of CR3 is 50.0 °C, and those temperatures were used to ensure that the primer CR1, CR2 and CR3 with CRISPR sequences effective annealing, no other non-specific reaction. Gram-positive purple chain coccus, there are differences in morphology, from different samples .The CTAB method was used to extract DNA. After PCR amplification, obtaining 11 different CRISPR sequences amplification results. In six samples of yogurt, there are five kinds of CRISPR sequences, four milk samples obtain three kinds of CRISPR sequences, three kinds of cheese has three deferent CRISPR sequences.

To accurately detect deadlocks in Network-on-Chip (NoC) as early as possible, a novel deadlock detection mechanism called Backward-probing Deadlock Detection (BDD) is proposed in this work, which can detect and resolve all existing deadlocks. It was realized using probe systems that generate probes for deadlock detection. A probe system includes a probe System Manager (SM) for turning on probe system, a probe Generator (GEN) for generating probes, a Link Selection (LS) connected to a Switch Allocation (SA), which is used for copying the generated probes, transmitting probes backward, and discarding probes when the probes find that the traversal path is just a congestion not a deadlock or when probe congestion occurs. There is also a TB Calculation (TBC) in LS for TB settings. Finally, a probe comparator (PB Comparator) is used for claiming deadlocks. Note that each port except the local one in a router has its own probe system.

Supply chain management is ultimately charactering the complementation of economic process now and future. Those not only promote the trend of high gradation of cost system and the differences of cost utilities that determined by supply chain operations, but also eliminate the effectiveness of traditional cost control, which based on cost-saving and money-grubbing consciousness. Therefore, On the basis of a review and notarizing of traditional cost theories, this paper examines the origin and properties of the expectation disparity of traditional cost theory and its theoretic tendencies in supply chain management context, and Its conclusion puts forward a suggestion for optimising cost systems and eliminating disparity in modern economies.