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ImportanceVitamin D deficiency is commonly associated with sarcopenia; however, the latest International Clinical Practice Guidelines for Sarcopenia do not recommend vitamin D supplementation for sarcopenia owing to a lack of an apparent therapeutic effect on the indices of sarcopenia among participants with replete vitamin D concentration (ie, 25-hydroxyvitamin D [25(OH)D] level >20 ng/mL) from randomized clinical trials. While there is consensus in all vitamin D guidelines that serum levels of 25(OH)D less than 10 ng/mL should be corrected, approximately 30% of the world population's 25(OH)D levels range from 10 to 20 ng/mL, and it remains unclear whether such suboptimal levels can maintain optimal health, including sarcopenia risk.ObjectiveTo investigate the association of serum 25(OH)D level, especially suboptimal levels, with sarcopenia risk.Design, setting, and participantsThis genome-wide genetic association study was performed from August 2022 to February 2023 among the 295 489 unrelated European participants from the UK Biobank (2006-2010). Nonlinear and standard mendelian randomization analyses were used to examine the association of serum 25(OH)D concentration with sarcopenia risk.ExposuresA weighted genetic risk score using 35 unrelated single-nucleotide variants from the UK Biobank and weights from the SUNLIGHT Consortium was selected as an instrumental variable for serum 25(OH)D concentration.Main outcomes and measuresThe primary outcome was sarcopenia, and the secondary outcomes consisted of grip strength, appendicular lean mass index, and gait speed.ResultsThe final genetic analyses included 295 489 participants (mean [SD] age, 56.3 [8.1] years; 139 216 female [52.9%]). There was an L-shaped association between genetically predicted serum 25(OH)D concentration and sarcopenia risk. The risk of sarcopenia decreased rapidly as 25(OH)D concentration increased until 20 ng/mL and then leveled off. The odds ratio of sarcopenia for serum 25(OH)D level of 10 vs 20 ng/mL was 1.74 (95% CI, 1.17-2.59). Similar patterns were also observed when the association between serum 25(OH)D concentration and risks of each of the sarcopenia indices were evaluated.Conclusions and relevanceIn this mendelian randomization genetic association study of adults in the UK Biobank, the findings supported a nonlinear association between suboptimal 25(OH)D levels and sarcopenia risk. Randomized clinical trials among participants with suboptimal 25(OH)D levels are required to verify the potential causality.

为及时监测大豆预处理车间刮板输送机在生产中出现的断链、脱链等故障问题，保障刮板输送机的设备安全，分析了刮板输送机断链、脱链的故障原因，并提出了将刮板断链保护器应用于刮板输送机中。刮板断链保护器由速度传感器与信号处理器组成，当刮板输送机出现断链、脱链故障时，速度传感器所传输的脉冲信号频率会下降，信号处理器通过检测脉冲信号频率快速有效地作出反应，快速停机并发出声光报警，保障设备和生产安全。断链保护器结构简单，安装方便，并且不影响刮板输送机的正常运行，适合应用于一些传统企业中。In order to timely monitor broken chain, chain loss and other failure problems in the production of scraper conveyor in the soybean pretreatment workshop, to ensure the equipment safety of the scraper conveyor, the causes of the failure of the scraper conveyor broken chain and chain loss were analyzed, and the application of scraper broken chain protector to the scraper conveyor was put forward. Scraper broken chain protector consists of speed sensor and signal processor. When the scraper conveyor appears broken chain or chain loss failure, the frequency of the plulses transmitted by the speed sensor decreases, and the signal processor can quickly and effectively respond to the rapid shutdown and sound and light alarm by detecting the pluse frequency to protect the equipment and production safety. Broken chain protector is simple in structure, easy to install, and does not affect the normal operation of the scraper conveyor, suitable for application in some traditional enterprises.

石蜡加热器是浸出车间石蜡尾气回收工艺中的重要设备，石蜡加热器温度闭环系统是典型的非线性、时变、不确定性系统，难以建立精确的数学模型。为提高石蜡加热器电动调节阀温度闭环控制效果，以检测石蜡加热器的温度偏差（e）和温度偏差变化率（ec）为输入，模糊PID控制器的KP、KI、KD为输出，构造了二输入三输出的模糊PID控制器。以西门子S7-300 PLC为下位机，WINCC组态软件为上位机，采用STEP 7软件编写模糊PID控制的算法程序，并将程序下载到S7-300 PLC存储卡中,利用S7-300 PLC对电动调节阀开度进行调节，从而实现石蜡加热器温度闭环控制。模糊PID控制器应用于浸出车间石蜡加热器温度闭环控制系统可以减少系统超调量，具有响应速度快、稳定性高等优点，提高了石蜡加热器温度闭环控制系统的运行效率。 Paraffin heater is an important equipment of paraffin vent gas recovery process in leaching workshop. The temperature closed-loop system of paraffin heater is a typical nonlinear, time-varying and uncertain system, which is difficult to establish an accurate mathematical model. In order to improve the temperature closed-loop control effect of electric regulating valve of paraffin heater, taking the temperature deviation e and temperature deviation change rate ec of paraffin heater as inputs and KP, KI and KD of fuzzy PID controller as outputs, a two input three output fuzzy PID controller was constructed. Taking Siemens S7-300 PLC as the lower computer and WINCC configuration software as the upper computer, the algorithm program of fuzzy PID control was compiled with STEP 7 software, and the program was downloaded to S7-300 PLC memory card. S7-300 PLC was used to adjust the opening of electric regulating valve, so as to realize the temperature closed-loop control of paraffin heater. The fuzzy PID controller applied to the temperature closed-loop control system of paraffin heater in leaching workshop can reduce the overshoot of the system, and has the advantages of fast response speed and high stability, thus improving the operating efficiency of the temperature closed-loop control system of paraffin heater.