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Based on the use of exiting testing equipment research, summarize the request of detection and analyze the existing problems. According to the signal characteristics of the aero-engine synthesis adjuster, designed a kind of test system based on virtual instrument for it, and developed a software system used for the adjuster in situ detection and offline testing. National Instruments launched Compact RIO platform. Adopted this platform as hardware system can realize test system open and integration designed very well, and simulated sensors for the offline test part of the system. This test system realized parameters calibrating, channel testing and fault diagnosis function etc. for the adjuster.

An objective analytical procedure for the investigation of damage mechanisms in the thermoplastic self-reinforced polyethylene (UHMWPE/PE) composites under quasi-static tensile load has been established, using Unsupervised Pattern Recognition (UPR) technique for the clustering task of Acoustic Emission (AE) signals. Focus is on the correlating between the obtained classes and their specific damage mechanisms. This was carried out by waveform visualization and Fast Fourier Transform analysis. Pure resin and fiber bundles were tested to collect typical waveforms of matrix cracking and fiber fracture respectively, in order to label the signal classes in the composites. The evolution process of various damage mechanisms in the composites revealed that the correlating method was effective. The AE characteristics of different damage modes found out in this study can be used as the reference for identifying unknown AE signals in the UHMWPE/PE composites. The established procedure is also potential in the investigation of failure mechanisms for composite materials with UPR technique.

Objective This study aimed to determine a contrast medium injection rate that ensures both accuracy for data and safety for operation by comparing hemodynamic parameters of brain CT perfusion imaging with varied injection rates. Methods Twenty-four healthy volunteers were divided into three groups based on contrast medium injection rates (4.5, 6.0, and 7.5 ml/s). For all subjects, CT perfusion scanning was started at 4 s after antecubital venous bolus of contrast media injection. A perfusion-analyzing software package was used to produce a time–density curve in the anterior cerebral artery and the superior sagittal sinus and calculate the regional cerebral blood flow (rCBF) in the gray matter and the white matter. The hemodynamic indices were compared among the three groups, and statistical analysis was carried out using the F test. Results The time for the arterial rise to reach the peak value for the 7.5-ml/s group was only 0.2 s ahead of the initiation time for the rise of the superior sagittal sinus. The differences of rCBF in the gray matter and the white matter among the three groups were statistically significant. rCBF in the gray matter and the white matter for the 7.5-ml/s group was 52.8 ml · min −1 100 g −1 · (±3.1) and 21.9 ml · min −1 · 100 g −1 (±2.4), respectively. Conclusions The use of the 7.5-ml/s injection rate can meet the prerequisite of the maximum slope model, and the resulting rCBF can be very close to that measured by positron emission tomography. Therefore, 7.5 ml/s was an ideal contrast medium injection rate.

Glomus tumors,also known as glomangiomas,are rare and originate in the neuromyoarterial glomus,a normal arteriovenous shunt which is abundantly supplied with nerve fibers and fulfills a temperature-regulating function.The classic location of glomus tumor is the subungual region,but the tumor can occur elsewhere in the skin,soft tissues,nerves,stomach,nasal cavity,and trachea.In the gastrointestinal(GI)tract the tumor occurs more often in the stomach than other parts,and typically occurs as a solitary submucosal nodule in the antrum.We reported a case of glomus tumor originating from the greater curvature of stomach which was studied with contrast-enhanced helical computed tomography (CT)and described the characteristic helical CT findings of the rare lesion.

The effects of silybin and tetrandrine on the survival of spontaneously hypertensive rats subjected to acute coronary artery occlusion were investigated. The mortality after acute coronary occlusion in spontaneously hypertensive rats (66.7%) was higher than that of control Wistar-Kyoto rats (20%, P < 0.05). Oral administration of silybin (300 mg/kg daily) for 8-12 days reduced mortality in spontaneously hypertensive rats (0, P < 0.01 in comparison with untreated spontaneously hypertensive rats). Administration of tetrandrine 40 mg/kg daily for 8-12 days reduced the mortality to some extent (22.2%, P = 0.051, as compared with control rats). Silybin reduced blood pressure and the incidence of post-occlusion arrhythmias in spontaneously hypertensive rats to the same extent as tetrandrine. Both silybin and tetrandrine decreased the severity of ventricular hypertrophy. Although there were significant decreases in risk zone and infarct zone in silybin- and tetrandrine-treated rats, the ratio of infarct to risk zone was not changed. The results implies that silybin may be beneficial when used in hypertensive patients who develop acute myocardial infarction.

To investigate the expression of midkine (MK) in eutopic and ectopic endometrium of patients with severe endometriosis and its clinical significance.Immunohistochemical streptavidin-biotin peroxidase (SP) method was used to detect MK expression and microvessel density (MVD) in eutopic and ectopic endometrium. Specimens of eutopic and ectopic endometrium were collected from 41 patients with serious endometriosis (study group) and 32 patients with uterine fibroid (control group).The positive rate of MK expression in the eutopic endometrium from study group was 63% (26/41). It was significantly higher than that in the ectopic endometrium from study group was 29% (12/41) and the eutopic endometrium from control group was 22% (7/32, P0.05). MK expression was positively correlated to microvessel density (r = 0.637, P0.05).Over-expression of MK protein is showed in the eutopic endometrium of patients with severe endometriosis and correlated to endometriotic angiogenesis. The change of MK expression in eutopic endometrium may be related to the pathogenesis of severe endometriosis.