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The ultra large aspect ratio gear structure is increasingly widely used in gearboxes for aerospace, high-speed equipment, and heavy equipment to meet the performance requirements of narrow center distance and high torque. The conventional gear specification calculation accuracy is difficult to meet the performance requirements of ultra large aspect ratio gears. The article comprehensively summarizes the current mainstream methods for gear modification and dynamic performance research. It is recommended to use the finite element method to calculate the bending deformation, shear deformation, compression deformation, gear matrix deformation, Hertz contact deformation, and gear meshing stiffness of the gear teeth, coupled with the bending and torsional deformation of the gear shaft under bearing constraints. In the presence of uncertain factors such as manufacturing and installation, accurate gear contact deformation and modification results can be calculated. Furthermore, a robust optimization method for uncertain systems is adopted to reduce the transmission error fluctuations of gears from the source of gearbox vibration, in order to achieve robust dynamic optimization effects.

Objective To analyze the genotypes and characteristics of HIV - 1 transmission network of newly reported HIV/ AIDS cases aged 50 and above in Yubei District of Chongqing and provide evidence for effective HIV - 1 transmission prevention in Yubei District. Methods Blood sample of newly reported cases aged 50 and above in 2020 - 2023 were collected for genetic analysis, partial Pol gene sequences were obtained to construct molecular transmission network. The factors associated with the subjects entering network and characteristics of cluster were further analyzed. Results A total of 351 Pol gene sequences were obtained and 9 HIV - 1 genotypes were detected. CRF07_BC (57. 0%, 200/351 ) was the major subtypes, followed by CRF08_BC( 19. 4%, 68/351), the rate of network entry was 57. 3%, and 44 clusters were formed. The number of nodes in clusters was between 2 - 25. People aged 60 and above ( 60 - 69years old : aOR = 2. 25, 95% CI $ 1. 34 -3. 80; 70 - 79years old $ aOR =2. 93,95% CI : 1. 52 - 5. 65 ), with local household registration in Yubei ( aOR = 3. 10, 95% CI : 1.4-5.52) and genotype CRF07_BC ( aOR = 2. 57, 95% CI: 1.47 -4.50) were more likely to have internet access. The proportion of high - risk spreaders was higher among males than among females. Conclusion CRF07_BC and CRF08_BC are the major genotypes of HIV/AIDS in people aged 50 years and above in Yubei District, and CRF07_BC is the genotype of key transmission cluster with high transmission risk. We should strengthen the intervention for the high - risk elderly, and monitor the molecular network dynamically to guide the precise intervention. [ABSTRACT FROM AUTHOR]

In recent years, the research on symptom management in peritoneal dialysis (PD) patients has shifted from a single symptom to symptom clusters and network analysis. This study collected and evaluated unpleasant symptoms in PD patients and explored groups of symptoms that may affect PD patients with a view to higher symptom management. The symptoms of PD patients were measured using the modified Dialysis Symptom Index. The symptom network and node characteristics were assessed by network analysis, and symptom clusters were explored by factor analysis. In this study of 602 PD patients (mean age 47.8 ± 16.8 years, 47.34% male), most had less than 2 years of dialysis experience. Five symptom clusters were obtained from factor analysis, which were body symptom cluster, gastrointestinal symptom cluster, mood symptom cluster, sexual disorder symptom cluster, and skin-sleep symptom cluster. Itching and decreased interest in sex may be sentinel symptoms, and being tired or lack of energy and feeling anxious are core symptoms in PD patients. This study emphasizes the importance of recognizing symptom clusters in PD patients for better symptom management. Five clusters were identified, with key symptoms including itching, decreased interest in sex, fatigue, and anxiety. Early intervention focused on these symptom clusters in PD patients holds promise for alleviating the burden of symptoms. [ABSTRACT FROM AUTHOR]

Objective: This study aims to explore the potential contribution of angiographic characteristics in the increased stroke risk among pediatric patients. Methods: This study retrospectively enrolled pediatric patients with ischemic, hemorrhagic, and asymptomatic moyamoya disease. Their hemispheres were categorized into five groups for the analysis of angiographic characteristics, which included Suzuki's stage, moyamoya vessels, lenticulostriate artery, thalamotuberal artery, thalamoperforating artery, anterior choroidal arteries, posterior choroidal arteries, and posterior cerebral artery involvement. Results: Two hundred and nineteen pediatric patients with four hundred and thirty-eight hemispheres were enrolled. There was no significant difference in collateral dilatation between asymptomatic and hemorrhagic hemispheres. However, asymptomatic hemispheres had significantly lower incidence of posterior cerebral artery involvement and Suzuki's stage compared to hemorrhagic (p = 0.008, p = 0.004) and ischemic hemispheres (p = 0.026, p < 0.001). Multivariate analysis revealed that Suzuki's stage (p = 0.002, 95% CI 1.261–2.867) is a risk factor for ischemia, while age (p < 0.001, 95% CI 0.712–2.014) and posterior cerebral artery involvement (p = 0.037, 95% CI 0.087–13.377) are risk factors for hemorrhage. Interpretation: Angiographic features in children with asymptomatic moyamoya disease resemble those observed in the hemorrhagic pediatric patients, indicating that greater attention should be focused on the risk of future hemorrhage in these patients, rather than on ischemia. Additionally, studies have demonstrated a correlation between posterior cerebral artery involvement and age with the incidence of hemorrhage. Monitoring angiographic characteristics may assist in tracking the transition from asymptomatic to symptomatic hemispheres. [ABSTRACT FROM AUTHOR]

BACKGROUND: Chronic excessive alcohol consumption can lead to alcoholic fatty liver, posing substantial health risks. l‐Theanine (LTA) and epigallocatechin gallate (EGCG) in tea exert antioxidant and hepatoprotective effects. However, the combined effects of LTA and EGCG on rats with alcoholic fatty liver, and the underlying mechanisms of such effects, remain unclear. In this study, Sprague Dawley (SD) rats were fed with alcohol for 6 weeks to induce alcoholic fatty liver. Subsequently, for another 6 weeks, the rats were administered LTA (200 mg kg−1 day−1), EGCG (200 mg kg−1 day−1), or a combination of LTA with EGCG (40 mg kg−1 day−1l‐Thea +160 mg kg−1 day−1 EGCG), respectively. RESULTS: The combined use of LTA and EGCG for alcoholic fatty liver disease had more significant effects than their individual administration. This combination reduced the activity of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) as well as the levels of hepatic triglyceride (TG), malondialdehyde (MDA), and reactive oxygen species (ROS) in the rats. The combined intervention also increased hepatic superoxide dismutase (SOD) and glutathione peroxidase activity. Reductions in hepatic fat accumulation and inflammatory responses were observed. The mechanism underlying these effects primarily involved the inhibition of fatty acid synthesis and the alleviation of lipid peroxidation through the downregulation of the mRNA and protein expression of TNF‐α, SREBP1c, and CYP2E1 and the upregulation of the mRNA and protein expression of ADH1, ALDH2, Lipin‐1, PPARαPPARα, AMPK, and PGC‐1α, thereby promoting the oxidative decomposition of fatty acids and reducing the synthesis of cholesterol and glucose. CONCLUSION: l‐Theanine and EGCG appear to be able to alleviate alcoholic fatty liver by modulating lipid metabolism and ameliorating oxidative stress, indicating their potential as natural active ingredients in anti‐alcoholic fatty liver food products. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This article discusses the establishment of a novel severe asthma canine model for research on respiratory intervention therapies. The researchers aimed to create a large animal model of asthma that closely mimics the clinical signs and features of severe asthma in humans. They exposed adult beagles to Toluene diisocyanate (TDI) via aerosol inhalation and observed pronounced asthma clinical signs, airway inflammation, and remodeling. The model also demonstrated the efficacy of respiratory intervention therapy. This model provides a valuable tool for studying the mechanisms and effectiveness of interventional pulmonological therapies for severe asthma. [Extracted from the article]