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Epidemiologic studies have shown alcohol plays a pivotal role in the development of osteonecrosis of the femoral head (ONFH). The aim of this study was to explore the underlying mechanism of alcohol-induced ONFH and the protective effect of pifithrin-α (PFTα). In vitro, we found ethanol treatment significantly activated p53, suppressed Wnt/β-catenin signaling and inhibited osteogenic-related proteins. Furthermore, by separating the cytoplasmic and nuclear proteins, we found ethanol inhibited osteogenesis by impairing the accumulation of β-catenin in both the cytoplasm and nucleus in human bone mesenchymal stem cells (hBMSCs), which resulted from activating glycogen synthase kinase-3β (GSK-3β). Therefore, PFTα, a p53 inhibitor, was introduced in this study to block the ethanol-triggered activation of p53 in hBMSCs and alcohol-induced ONFH in a rat model. In vivo, we established alcohol-induced ONFH in rats and investigated the protective effect of PFTα. Hematoxylin & eosin (H&E) staining combined with TdT-mediated dUTP nick end labeling (TUNEL), cleaved caspase-3 immunohistochemical staining, and micro-CT images revealed substantial ONFH in the alcohol-administered rats, whereas significantly less osteonecrosis developed in the rats injected with PFTα. Osteogenic-related proteins, including osteocalcin, osteopontin and collagen I, were significantly decreased in the alcohol-administered rats, whereas these results were reversed in the PFTα-injected rats. Fluorochrome labeling similarly showed that alcohol significantly reduced the osteogenic activity in the rat femoral head, which was blocked by the injection of PFTα. In conclusion, PFTα had an antagonistic effect against the effects of ethanol on hBMSCs and could be a clinical strategy to prevent the development of alcohol-induced ONFH.

The motion commands to feed drives constitute a major source for excitation of the vibrations. In this paper the vibration of feed drive caused by the motion commands is simulated by using a mathematic method. The mechanical transmission system is modeled as a dual inertia system. Three typical trajectories are used to analyze the effect of motion profiles on feed drive vibration by using a simulation model of feed drive controller.

Yi People Ancient Town of Chuxiong is a modern real estate development project with commercial, residential and cultural tourism. Based on inheriting traditional vernacular landscape features, its development and construction were built by modern technology, meanwhile, respected the original build system. This paper studied the Spatial Form of Yi People Ancient Town through the space analysis of street, node, building and spiritual culture from several aspects. This is very important reference value, academic value and practical significance for guiding the construction of modern urban environment scientifically.

The Pauwels angle has been used widely, however an accurate evaluation of this angle is difficult because of deformity of the affected lower extremity. Therefore we designed a new measurement of the orientation of femoral neck fracture and applied this in a retrospective study to assess: (1) its reproducibility, (2) its advantages compared with the Pauwels angle, (3) its relationship with the short-term prognosis treated with three cannulated compression screws.This new measurement is reproducible and has some reference meaning for the treatment of femoral neck fractures.Two hundred and twenty-eight patients with femoral neck fractures treated with three cannulated compression screws were retrospectively analyzed. The VN angle, which was the angle between the fracture line and the vertical of the neck axis, and the Pauwels angle were measured respectively. The method of ICC was performed to assess the reproducibility of the two angles, and the absolute value of difference in pre-operative and post-operative radiographs was used to evaluate the uniformity of the two angles. These fractures were divided into four groups according to VN angle (VN0° (n=92), 0°≤VN10° (n=82), 10°≤VN15° (n=26), VN≥15° (n=28)), and the short-term (within 6 months) fixation results of radiographs in these fractures were evaluated.The ICC of the VN angle and the Pauwels angle in pre-operative radiographs were 0.937 (95% confidence interval (CI): 0.922-0.950) and 0.942 respectively (95% CI: 0.914-0.970), indicating both angles had a good inter-rater reproducibility. However, there was a great difference between the Pauwels angle in pre-operative and post-operative radiographs (P=0.037), the absolute difference was 10.66±6.47 (range: 1.72-38.48), while no statistical difference for the VN angle (P=0.084) and the absolute difference was 2.20±1.63 (range: 0.05-7.56). The overall fixation failure rate which was defined as screw loosening, varus collapse, obvious fracture displacement or femoral neck shortening was 11.84%, and the mean failure rates according to VN angles were respectively 0%, 3.24% (95% CI: 1.64-4.84), 22.69% (95% CI: 16.43-28.96), 65.45% (95% CI: 59.36-71.53). The mean failure rates of fractures according to post-operative Pauwels angle (30°, 30-50°,50°) were respectively 0%, 1.46% (95% CI: 1.42-1.50) and 36.24% (95% CI: 34.93-37.54).The VN angle has a good inter-rater reproducibility, a higher reliability than the Pauwels angle and is closely related to the short-term prognosis of femoral neck fractures treated with cannulated compression screws.Level IV, retrospective diagnostic study.

In the condition monitoring and fault diagnosis, useful information about the incipient fault features in the measured signal is always corrupted by noise. Fortunately, the Kalman filtering technique can filter the noise effectively, and the impending system fault can be revealed to prevent the system from malfunction. This paper has discussed recent progress of the Kalman filters for the condition monitoring and fault diagnosis. A case study on the rolling bearing condition monitoring and fault diagnosis using Kalman filter and support vector machine (SVM) has been presented. The analysis result showed that the integration of the Kalman filter and SVM was feasible and reliable for the rolling bearing condition monitoring and fault diagnosis and the fault detection rate was over 96.5%.

Background The Pauwels angle has been used widely, however an accurate evaluation of this angle is difficult because of deformity of the affected lower extremity. Therefore, we designed a new measurement of the orientation of femoral neck fracture and applied this in a retrospective study to assess: 1) its reproducibility, 2) its advantages compared with the Pauwels angle, 3) its relationship with the short-term prognosis treated with three cannulated compression screws. Hypothesis This new measurement is reproducible and has some reference meaning for the treatment of femoral neck fractures. Methods Two hundred and twenty-eight patients with femoral neck fractures treated with three cannulated compression screws were retrospectively analyzed. The VN angle, which was the angle between the fracture line and the vertical of the neck axis, and the Pauwels angle were measured respectively. The method of ICC was performed to assess the reproducibility of the two angles, and the absolute value of difference in pre-operative and post-operative radiographs was used to evaluate the uniformity of the two angles. These fractures were divided into four groups according to VN angle (VN n = 92), 0° ≤ VN n = 82), 10° ≤ VN n = 26), VN ≥ 15° ( n = 28)), and the short-term (within 6 months) fixation results of radiographs in these fractures were evaluated. Results The ICC of the VN angle and the Pauwels angle in pre-operative radiographs were 0.937 (95% confidence interval [CI] 0.922–0.950) and 0.942 respectively (95% CI 0.914–0.970), indicating both angles had a good inter-rater reproducibility. However, there was a great difference between the Pauwels angle in pre-operative and post-operative radiographs ( P = 0.037), the absolute difference was 10.66 ± 6.47 (range, 1.72–38.48), while no statistical difference for the VN angle ( P = 0.084) and the absolute difference was 2.20 ± 1.63 (range, 0.05–7.56). The overall fixation failure rate which was defined as screw loosening, varus collapse, obvious fracture displacement or femoral neck shortening was 11.84%, and the mean failure rates according to VN angles were respectively 0%, 3.24% (95% CI 1.64–4.84) 22.69% (95% CI 16.43–28.96), 65.45% (95% CI 59.36–71.53). The mean failure rates of fractures according to post-operative Pauwels angle ( 50°) were respectively 0%, 1.46% (95% CI 1.42–1.50) and 36.24% (95% CI 34.93–37.54). Discussion The VN angle has a good inter-rater reproducibility, a higher reliability than the Pauwels angle and is closely related to the short-term prognosis of femoral neck fractures treated with cannulated compression screws. Level of evidence Level IV, retrospective diagnostic study.