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Purpose Previous studies have indicated that the prevalence rate of hypertension in adolescents is high, but it has not received much attention and the influencing factors are unclear, especially in Yunnan Province, China. Materials and methods A cluster sampling method was used to investigate 4781 freshmen in a college in Kunming, Yunnan Province from November to December. Demographic and lifestyle data were collected using questionnaires, and height, weight and blood pressure were measured. Decision tree model of hypertension in college students was established by Chi-square automatic interactive detection method. Results Prevalence of prehypertension of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were detected in 33.9% and 32.1%, respectively. Prevalence of hypertension of SBP and DBP was detected in 1.2% and 7.2%, respectively. The hypertension and prehypertension decision tree of SBP has gender (χ2 = 728.64, p

Sapphire optical components are widely used in various industrial sectors. However, they are currently not available through efficient and highly accurate ultra-precision cutting. Therefore, this paper investigates the effect of cutting speed, a key factor in ultra-precision cutting, on the removal behaviour of sapphire materials. The plunge-cuts tests at different cutting speeds (10, 20 and 30 mm/s) have been conducted. The groove surface morphology, critical cutting depth for ductile-brittle transition, cutting force and tool wear of each plunge-cuts test with various cutting speed test were analysed. The experimental results shown that increasing the cutting speed is beneficial to obtain less defective machined surfaces and increase the critical cutting depth for ductile-brittle transition. However, at the same time, the cutting force increases dramatically in the brittle removal mode during high-speed cutting, which leads to severe tool wear. Therefore, increasing the cutting speed to meet the requirements of ultra-precision cutting and machining within the critical cutting depth is a highly efficient measure for obtaining sapphire optical surfaces.

In view of the deficiencies of GPS in the urban environment, such as signal occlusion, multipath and Non-LOS, this paper proposes a solution that using a low-cost monocular camera instead of inertial navigation system to combine with GPS. Firstly, considering that the actual road conditions of the vehicle are mostly plane and in order to reduce the computational resources of visual odometer (VO), this paper establishes a VO solving model based on plane constraint; then the VO&GPS loose coupling model is proposed. The position error and yaw angle error of the two sensors are taken as input, and the errors are filtered by the adaptive Kalman filter. Experiments show that the positioning effect of VO&GPS loose coupling system is better than that of single GPS, and it can suppress the drift of VO, which can meet the positioning requirements when satellite signals are interfered in a short time.

BACKGROUND Few reports have focused on the association between apparent treatment-resistant hypertension (aTRH) and cardiovascular (CV) mortality in peritoneal dialysis (PD) population, thus we conducted this retrospective cohort to explore it. METHODS This was a retrospective cohort study conducted from January 2011 to January 2020 with PD patients in 4 Chinese dialysis centers. aTRH was defined according to the American College of Cardiology and American Heart Association guidelines. aTRH duration was calculated as the total number of months when patients met the diagnostic criteria in the first PD year. The primary outcome was CV mortality, and the secondary outcomes were CV events, all-cause mortality, combined endpoint (all-cause mortality and transferred to hemodialysis [HD]), and PD withdrawal (all-cause mortality, transferred to HD, and kidney transplantation). Cox proportional hazards models were used to assess the association. RESULTS A total of 1,422 patients were finally included in the analysis. During a median follow-up period of 26 months, 83 (5.8%) PD patients incurred CV mortality. The prevalence of aTRH was 24.1%, 19.9%, and 24.6% at 0, 3, and 12 months after PD initiation, respectively. Overall, aTRH duration in the first PD year positively associated with CV mortality (per 3 months increment, adjusted hazards ratio [HR], 1.29; 95% confidence interval 1.10, 1.53; P  = 0.002). After categorized, those with aTRH duration more than 6 months presented the highest adjusted HR of 2.92. Similar results were found for secondary outcomes, except for the CV event. CONCLUSIONS Longer aTRH duration in the first PD year is associated with higher CV mortality and worse long-term clinical outcomes. Larger studies are warranted to confirm these findings. CLINICAL TRIALS REGISTRATION There is no clinical trial registration for this retrospective study. [ABSTRACT FROM AUTHOR]

Simple Summary: Tibetan sheep are integral to the ecosystems and livelihoods of the Tibetan Plateau; however, their breeding practices limit their production and growth. Candidate genes myostatin (MSTN)and Callipyge have been recognized as important for improving growth traits in livestock. This research examined the polymorphic loci of these genes in Tibetan sheep and their association with growth traits. The results indicated that SNP loci of MSTN could potentially be utilized as a molecular indicator for early growth traits in Tibetan sheep. Tibetan sheep are vital to the ecosystem and livelihood of the Tibetan Plateau; however, traditional breeding methods limit their production and growth. Modern molecular breeding techniques are required to improve these traits. This study identified a single nucleotide polymorphism (SNP) in myostatin (MSTN) and Callipyge in Tibetan sheep. The findings indicated notable associations between MSTN genotypes and growth traits including birth weight (BW), body length (BL), chest width (ChW), and chest circumference (ChC), as well as a particularly strong association with cannon circumference (CaC) at 2 months of age. Conversely, Callipyge polymorphisms did not have a significant impact on Tibetan sheep. Moreover, the analyses revealed a significant association between sex and BW or hip width (HW) at 2 months of age and ChW, ChC, and CaC at 4 months of age. Furthermore, the study's results suggested that the genotype of MSTN as a GA was associated with a notable sex effect on BW, while the genotype of Callipyge (CC) showed a significant impact of sex on CaC at 2 months of age. These results indicated that the SNP of MSTN could potentially serve as a molecular marker for early growth traits in Tibetan sheep. [ABSTRACT FROM AUTHOR]

As a major agricultural province, understanding the spatial distribution characteristics of non-point source pollution in Liaoning Province plays a crucial role in preventing and controlling non-point source pollution. This paper uses the pollution discharge coefficient method to calculate the TN and TP load of non-point source pollution in each city of Liaoning Province in 2019. The results indicate that: (1) In 2019, the emissions of TN and TP from non-point source pollution in Liaoning Province were 245.6 thousand t and 23.2 thousand t, respectively. Livestock and poultry farming is the main source of TN and TP pollution. (2) The total amount of standard pollution load was 361.269 billion m3. TN is the main source of non-point source pollution, with TN and TP accounting for 67.96% and 32.04%, respectively. Overall, pollution in the central and western regions is more serious than in the eastern regions, while pollution in the plain areas is worse than in the mountainous and hilly areas. Chaoyang should be a key focus in terms of the prevention and control of non-point source pollution, and the abundant total water resources play a crucial role in reducing pollution levels. [ABSTRACT FROM AUTHOR]

In this paper, the fixed-time multi-switch combination–combination synchronization (FTMSCCS) of fractional-order chaotic systems with uncertainties and external disturbances is studied. The appropriate sliding mode surface and controller are proposed based on a Lyapunov theorem, and fixed-time multi-switching combination–combination synchronizations between four fractional-order chaotic systems are realized. The Lyapunov function is designed to prove the feasibility of the controller theoretically, and the effectiveness and robustness of the synchronization mechanism are further verified by numerical simulations. The advantage of this article is that it extends fixed-time synchronization to multi-switch combination–combination synchronization, enabling synchronization for a limited time, while increasing the complexity of the synchronization mechanism and improving its confidentiality in communication applications. [ABSTRACT FROM AUTHOR]