Design and Dynamic Simulation of a Novel Traveling Wave Linear Ultrasonic Motor.

To overcome the problem of frequency consistency and simplify the design process of linear ultrasonic motor, a novel traveling wave linear ultrasonic motor with a ring-type stator is proposed in this paper. The combination of two orthogonal bending vibration modes with the same order is selected as the operating mode of the motor. A traveling wave along the side of the stator is utilized to drive the slider to move linearly. The stator adopts a ring symmetrical structure, which can effectively ensure that the resonance frequencies of the two vibration modes are consistent. Thus, we do not need to tune the frequencies of the two vibrations by constantly adjusting the shape of the stator or designing complex clamping parts to fix the stator without making any influence on the vibrations. Meanwhile, a three-dimensional finite element model of the motor is built. Using the model, we obtain the elliptical motion trajectories of the stator driving surface, the output performance of the motor, the sticking-slipping-separation contact characteristic between the stator and the slider and fabricate and measure a prototype of the proposed motor.

Association of mild to moderate kidney dysfunction with coronary artery calcification in patients with suspected coronary artery disease.

OBJECTIVES: To report the association between kidney dysfunction and coronary artery calcification (CAC) score (CACS) among patients with clinically suspected coronary artery disease (CAD). METHODS: We prospectively included 1,572 consecutive patients with clinically suspected CAD who underwent ECG-gated cardiac CT scans using 64-multidetector row computed tomography. CACS was quantified using a previously described method. Renal function was assessed by the estimated glomerular filtration rate (eGFR). Ordinal logistic regression and Pearson correlation were used to analyze the association between eGFR and CACS. RESULTS: Patients with higher CACS were older, more had a history of hypertension, diabetes and tobacco use, and they were more likely to have an atherogenic lipid profile, higher systolic blood pressure, diastolic blood pressure, hemoglobin A1c, body mass index and C-reactive protein (CRP) and lower eGFR when compared with those patients without CAC or with lower CACS. The unadjusted correlation coefficient of eGFR and CACS was -0.259 (p < 0.001). This remained significant after adjustment for age, gender, hypertension, diabetes, hyperlipidemia, tobacco use and CRP (R = -0.156, p < 0.001). Ordinal logistic regression analysis showed that age, hypertension, diabetes, CRP and eGFR exerted independent influences on CACS. CONCLUSIONS: Kidney dysfunction was an independent predictor of CACS in patients with clinically suspected CAD. Further prospective multicenter studies are needed to confirm this finding.

Low- to high-density lipoprotein cholesterol ratio followed by coronary computed tomography angiography improves coronary plaque classification accuracy.

Coronary computed tomography angiography (CCTA) is a noninvasive test for detection and analysis of coronary plaques morphology and classification. The low- to high-density lipoprotein cholesterol (L/H) ratio is associated with plaques vulnerability. The study aims to investigate the diagnostic accuracy of CCTA and L/H ratio for plaques classification. We enrolled 212 patients with coronary artery single-vessel disease who performed preoperative CCTA and Intravascular ultrasound (IVUS)-guided invasive coronary angiography. Patients were assigned to the acute coronary syndrome (ACS) group (n = 129) and stable angina pectoris (SAP) group (n = 83). CCTA showed that patients with ACS had more soft plaque and less calcific plaque than those with SAP. The plaque volume and remodeling index measured by CCTA showed good correlation with those measured by IVUS. IVUS identified 91 soft, 58 mixed and 63 calcific plaques in this cohort. For diagnosis of noncalcified plaque (soft and mixed), CCTA had the sensitivity and specificity of 87.9% and 90.4%, respectively. While refer to the further diagnosis of mixed plaque from noncalcified plaque, the sensitivity and specificity was 88.4% and 88.8%, respectively. The L/H ratio was gradually decreased from soft plaque to calcific plaque. If the patients had both the two characteristics (L/H ≥ 2.55 and CCTA), the sensitivity, and specificity were improved in diagnosing noncalcified plaque or mixed plaque. In conclusion, a combined application of CCTA and L/H ratio improves the diagnostic accuracy for coronary noncalcified plaque or mixed plaque as compared to CCTA along.

Anti-VEGF Therapy with Bevacizumab--limited cardiovascular toxicity.

PURPOSE: This analysis was conducted to evaluate cardiovascular toxicity of commonly used anti-VEGF therapeutic agent, bevacizumab, in treating patients with cancer. METHODS: Clinical studies evaluating the efficacy and safety of bevacizumab-based regimens on response and safety for patients with cancer were identified using a predefined search strategy, allowing cardiovascular toxicity and other side effects of treatment to be estimated. RESULTS: In bevacizumab based regimens, 4 clinical studies including 282 patients with advanced cancer (including gliomas, cervical, breast and ovarian cancer) were considered eligible for inclusion. These bevacizumab-based regimens included docetaxel, irinitecan and carboplatin. Systematic analysis suggested that, of 282 patients treated by bevacizumab based regimens, hypertension and thrombo-embolism occurred in 2.5% (7/282), while only 3 patients reported cardiovascular events (1.1%). No treatment related death occurred in bevacizumab based treatment. CONCLUSION: This systemic analysis suggests that bevacizumab based regimens are associated with reasonable and accepted cardiovascular toxicity when treating patients with gliomas, cervical, breast and ovarian cancer.