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Load carrying capacity is one of the most important properties of aviation lubricating oils, which is evaluated by using the Ryder gear machine according to the FED-STD-791D Method 6508.2. However, the Ryder gear machine and test gears are not currently available to the public. In this study, commercially available FZG high-speed gear test machine and FZG test gears A20 and C-PT were used to establish a new method for evaluation of aviation lubricating oils. The test conditions were determined according to the Ryder gear test method and the FZG Ryder test method. Results show that the developed FZG-C HS test method using C-PT gears can distinguish among the aviation lubricating oils with different scuffing load capacities as the Ryder gear test method does. The FZG-C HS test can serve as an alternative test method to the Ryder gear test to evaluate the load carrying capacity of aviation lubricating oils. [ABSTRACT FROM AUTHOR]

[Objective] The dynamic change of leaf area index (LAI) and its response to climatic factors in Ulanqab City were studied in order to provide a scientific basis for rational resource allocation and ecological conservation. [Methods] Based on the Copernicus Climate Change Service PROBA-V LAI data and meteorological data from July to August during the period of 2000—2019, the spatiotemporal variation of LAI and its relationship with temperature, precipitation, and soil moisture in Ulanqab City were explored using linear trend analysis, coefficient of variation analysis and correlation analysis. [Results] ① Average LAI showed a fluctuating upward trend at a growth rate of 0.01 per year in Ulanqab City during the study period. Significant differences were found in the spatial distribution of LAI, which was characterized by high LAI in the southeast and low LAI in the northwest. ② Although 88.3% of the study area showed an increasing trend for LAI, the change of LAI was relatively unstable during the study period. A significant increasing trend was found in most of Xinghe County, the east of Fengzhen City, the west of Liangcheng County, the southwest of Siziwang Banner, and the central and northern parts of Chahar Right Middle Banner, while a slowly increasing or decreasing trend was found in most areas of Houshan Mountain in the north of Yinshan Mountain. ③ LAI showed a significant negative correlation with temperature, and a highly significant positive correlation with precipitation and soil moisture. The correlation of LAI with soil moisture was higher than that of precipitation and temperature. ④ No significant difference was found in the spatial distribution of correlation coefficients between LAI and temperature, precipitation, and soil moisture. Most areas had negative correlations between LAI and temperature, with 45.4% of the study area showing significant negative correlations. LAI had significant positive correlations with precipitation and soil moisture, and the area of significant correlation between LAI and soil moisture was larger than that of precipitation. [Conclusion] During 2000—2019, the LAI of vegetation in Ulanqab City showed an increasing trend and obvious spatial heterogeneity. Soil moisture was the decisive factor affecting vegetation growth.

Intracranial atherosclerotic disease tends to affect multiple arterial segments. Using whole-brain vessel wall imaging, we sought to study the differences in plaque features among various types of plaques in patients with a recent unilateral anterior circulation ischemic stroke. Sixty-one patients with unilateral anterior circulation ischemic stroke were referred to undergo whole-brain vessel wall imaging (before and after contrast) within 1 month of symptom onset for intracranial atherosclerotic disease evaluations. Each plaque was classified as a culprit, probably culprit, or nonculprit lesion, according to its likelihood of causing the stroke. The associations between plaque features (thickening pattern, plaque-wall contrast ratio, high signal on T1-weighted images, plaque contrast enhancement ratio, enhancement grade, and enhancement pattern) and culprit lesions were estimated using mixed multivariable logistic regression after adjustment for maximum wall thickness. In 52 patients without motion corruption in whole-brain vessel wall imaging, a total of 178 intracranial plaques in the anterior circulation were identified, including 52 culprit lesions (29.2%), 51 probably culprit lesions (28.7%), and 75 nonculprit lesions (42.1%). High signal on T1-weighted images (adjusted odds ratio, 9.1; 95% confidence interval, 1.9-44.1; P=0.006), grade 2 (enhancement ratio of plaque ≥ enhancement ratio of pituitary) contrast enhancement (adjusted odds ratio, 17.4; 95% confidence interval, 1.8-164.9; P=0.013), and type 2 (≥50% cross-sectional wall involvement) enhancement pattern (adjusted odds ratio, 10.1; 95% confidence interval, 1.3-82.2; P=0.030) were independently associated with culprit lesions. High signal on T1-weighted images, grade 2 contrast enhancement, and type 2 enhancement pattern are associated with cerebrovascular ischemic events, which may provide valuable insights into risk stratification.

Aims: This study aimed to investigate the impact of the triglyceride‐glucose index (TyG index) on clinical consequences in individuals with large vascular occlusion (LVO)‐induced acute ischemic stroke (AIS) following endovascular treatment (EVT). Methods: We conducted a single‐center retrospective cohort study, including AIS with LVO who underwent EVT. Patients were categorized into TyG index groups, calculated as "(fasting triglyceride [mg/dL] × fasting blood glucose [mg/dL]/2)." Clinical outcomes were assessed, including poor outcome (modified Rankin Scale [mRS] > 2 [3–6]) at 90 days, early neurological deterioration (END), symptomatic intracranial hemorrhage (sICH), and 90‐day mortality after EVT. Logistic regression and restricted cubic splines (RCS) were used to examine the relationship between the TyG index and clinical outcomes. Receiver operating characteristic (ROC) curve was constructed to evaluate the prognostic capacity of the TyG index. Results: A total of 424 patients were included. Higher TyG levels were associated with worse functional outcome at 90 days (per unit: p = 0.006), sICH (per unit: p = 0.002, T3 versus T1: p = 0.004), and 90‐day mortality (T2 versus T1: p = 0.011, T3 versus T1: p = 0.029) in logistic regression. A RCS model revealed a linear association between the TyG index and poor outcome at 90 days, sICH, and 90‐day mortality (p for nonlinearity > 0.05). In ROC curve analysis, the traditional risk factors model (area under the curve [AUC]: 0.824, 95% CI: 0.784–0.859) was outperformed by the conventional risk factors + TyG index model (AUC: 0.845, 95% CI: 0.807–0.878) in predicting poor outcome (p = 0.021). Conclusion: A higher TyG index is associated with worse clinical outcomes in LVO‐induced AIS patients after EVT. Additionally, the TyG index enhances risk prediction of traditional risk factors for poor outcome. [ABSTRACT FROM AUTHOR]

Our objective is to clarify the effects of acupuncture on hippocampal connectivity in patients with Alzheimer disease (AD) using functional magnetic resonance imaging (fMRI). Twenty-eight right-handed subjects (14 AD patients and 14 healthy elders) participated in this study. Clinical and neuropsychological examinations were performed on all subjects. MRI was performed using a SIEMENS verio 3-Tesla scanner. The fMRI study used a single block experimental design. We first acquired baseline resting state data during the initial 3 minutes and then performed acupuncture stimulation on the Tai chong and He gu acupoints for 3 minutes. Last, we acquired fMRI data for another 10 minutes after the needle was withdrawn. The preprocessing and data analysis were performed using statistical parametric mapping (SPM5) software. Two-sample t-tests were performed using data from the two groups in different states. We found that during the resting state, several frontal and temporal regions showed decreased hippocampal connectivity in AD patients relative to control subjects. During the resting state following acupuncture, AD patients showed increased connectivity in most of these hippocampus related regions compared to the first resting state. In conclusion, we investigated the effect of acupuncture on AD patients by combing fMRI and traditional acupuncture. Our fMRI study confirmed that acupuncture at Tai chong and He gu can enhance the hippocampal connectivity in AD patients.