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HL-3 is a new medium-sized copper conducting tokamak, which is dedicated to the plasma shaping control for plasma high performance and flexible operation, especially the advanced divertor configurations. According to the physics needs of the project, three types of magnetic pickup coils are designed and developed on HL-3 for magnetic field measurements. The coils emphasize different geometry sizes and array layouts. The coils are installed carefully by using high-precision positioning equipment to ensure the measurement accuracy of the system. After calibration, the magnetic field measurements are supplied for real-time equilibrium reconstruction and plasma control, e.g., with snowflake-shaped divertor configuration reconstruction. Mirnov coils satisfy the requirements for physical analysis, including determining the mode number from raw signals and detecting the magnetohydrodynamic instabilities. [ABSTRACT FROM AUTHOR]

Externally generated, axial magnetic fields used to confine high-current plasma beams in compact linear devices are usually 0.5 Tesla or less and can be insufficient to suppress plasma instabilities. Such an issue is addressed in this study by closely winding the current-carrying cable around a small chamber attached to the end of a linear device. The magnetic field generated inside the small chamber during the high-current pulse reached 0.8 Tesla at the peak current of 10.83 kA. Formation of a steady plasma beam through a mixture of argon, hydrogen and helium was photographed by a high-speed camera at the instant of the peak current. The beam width profile starts from over 24.8 mm at the upstream location and becomes thinner with distance down-stream. At the location of laser-interferometer measurement, at the right-most viewing window on the test chamber, the beam width was estimated as 7.4 mm and plasma density was evaluated to be 1.0 × 1022 m−3, an increase of two orders of magnitude compared to a previous study. A simple relationship was derived for the plasma density as a function of beam width. Based on examination of the metal target at the far end, the final beam width was estimated as 50 µm, with the plasma density evaluated to be 4.31 × 1022 m−3, with a calculated ion energy of 4.35 keV, consistent with x-ray spectrum measurements. [ABSTRACT FROM AUTHOR]

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A novel push-pull modulator based scheme to generate W-band millimeter-wave (mm-wave) vector signal was proposed and experimentally demonstrated. Related to an I/Q modulator, push-pull modulator has the advantages of simple architecture, small insertion loss and low cost. Through combining one 40 GHz upper sideband (USB) using a quadrature-phase-shift-keying (QPSK) modulation with a −40 GHz unmodulated lower sideband (LSB), a QPSK modulated 4 G-Baud 80 GHz single sideband vector mm-wave signal was successfully generated. [ABSTRACT FROM AUTHOR]

This paper reports an innovative pattern recognition technique for fracture microstructure images based on Bi-dimensional empirical mode decomposition (BEMD) and nonconvex penalty minimization Lq (q = 0.5) regular sparse representation-based classification (NPMLq-SRC) algorithm. The detailed procedures of this work can be divided into three steps, i.e., the preprocessing stage, the feature extraction stage and the image classification stage. We test and validate the proposed method through real data from metallic alloy fracture images. The case verification results show that our proposal can obtain a much higher recognition accuracy than the conventional Back Propagation Neural Networks (BPNN for short), the L1-norm minimization sparse representation-based classification (L1-SRC) and the BEMD combined with L1-norm minimization sparse representation-based classification (BEMD+L1-SRC) methods, respectively. Specifically, the proposed BEMD+NPMLq-SRC (q = 0.5) method outperforms the BEMD+L1-SRC method by 3.33% improvement of the average recognition accuracy, and outperforms L1-SRC method by 14.06% improvement of the average recognition accuracy, respectively. [ABSTRACT FROM AUTHOR]

Ahigh-frequency magnetic probe system is designed, calibrated and constructed on the HL-2A tokamak. To investigate the factors which affect the probe frequency response, the inductance and capacitance in the probe system are analyzed using an equivalent circuit. Suitable sizes and turn number of the coil, and the length of transmission cable are optimized based on the theory and detailed test in the calibration. To deal with the frequency response limitation and bake-out, the ceramic grooved technique is used and the probe is wound with a bare copper wire. A cascade filter is manufactured with a suitable bandwidth as well as a good phase consistency between channels. The system has been used in the experiment to measure high frequency (≤300 kHz) magnetohydrodynamic fluctuations, which can meet the requirement of physical analysis on HL-2A. [ABSTRACT FROM AUTHOR]

A physics-based analytical model to assess residual stresses in additive manufacturing made of metallic materials is presented and validated experimentally. The model takes into consideration the typical multi-pass aspect of additive manufacturing. First, the thermal signature of the process is assessed by predicting the temperature for the problem of a moving heat source, then, the thermally induced stresses in a homogenous semi-infinite medium are determined. Taking the thermal stresses as input, the residual stresses are calculated analytically to obtain the distribution across the depth. Good agreement is obtained between the analytical prediction and X-ray measurements made on Selective Laser Melted 316L Stainless Steel. In addition, the analytical approach enables in-depth interpretations of results with basis in the true mechanisms of the process. Thus, the present model appears as a promising tool for optimization of process parameters in additive manufacturing, which in turn will improve the understanding of process parameters and their effect on properties of the final product. [ABSTRACT FROM AUTHOR]

What is known and objectives Voriconazole is a triazole antifungal agent and is extensively metabolized via cytochrome P450 ( CYP450); therefore, special precautions need to be taken when co-administered with a known CYP450 inducer, which may lead to treatment failure. The influence of some CYP450 inducers on the pharmacokinetics of voriconazole has been described in previous studies, but a systematic review was lacking. In this study, we carried out a systematic review to assess the influence of CYP450 inducers on the pharmacokinetic ( PK) parameters of voriconazole. Methods Pubmed, Embase, Cochrane Library, Clinicaltrials.gov and three Chinese databases ( CNKI, CBM and WanFang) were searched through January 2016. Interventional and observational studies comparing the PK parameters of voriconazole used alone or with CYP450 inducers in healthy volunteers and patients were included. The outcomes included were the area under the plasma concentration-time curve ( AUC), peak plasma concentrations ( Cmax) and trough plasma concentrations ( Cmin). The quality of the included studies was assessed using Cochrane's risk of bias tool, Newcastle-Ottawa Scale ( NOS) and a modified risk of bias tool for pharmacokinetic before-and-after studies. Results and discussion Sixteen studies were included in this review: three randomized controlled trials ( RCTs), five single-arm before-after studies ( SBAs), six cohort studies and two case reports. All studies except case reports had moderate to high quality. Of the 11 inducers reviewed, efavirenz, ritonavir (chronic use), phenytoin, rifampin and rifabutin significantly decreased mean AUC and Cmax of voriconazole; St John's wort significantly decreased only mean AUC; rifampin, rifabutin, phenobarbital and carbamazepine significantly decreased mean Cmin. Etravirine and Ginkgo biloba did not reveal any such influence. The influence of glucocorticoids may depend on its type and dose. What is new and conclusions To conclude, the combination use of high-dose efavirenz, high-dose ritonavir, St John's wort, rifampin, phenobarbital, or carbamazepine with voriconazole is contraindicated as instructed in the drug label. Low-dose efavirenz, low-dose ritonavir, rifabutin and phenytoin may be used together with voriconazole provided TDM and dose adjustment of voriconazole. Moreover, this study shows there is low risk of drug-drug interactions when voriconazole is co-administered with etravirine or G. biloba; however, whether the use of glucocorticoids has a clinically significant effect on voriconazole still requires more evidence. This study also highlights the lack of clinical studies and future high-quality studies assessing the influence of CYP450 inducers on voriconazole. PK parameters and dosing optimization should be designed to provide a more definitive answer regarding the necessity of TDM and the recommendations for dose adjustment of voriconazole. [ABSTRACT FROM AUTHOR]

The effects of process parameters on micro-texture evolution of Al alloy 7075 in machining under extreme conditions were investigated. For the first time, the process parameters in machining are related to the micro-texture evolution below the machined surface, through a computational modeling framework verified by robust experimentation. Finite element analyses (FEA) were performed to obtain the mechanical loads that the material experiences due to chip removal. The viscoplastic self-consistent (VPSC) approach was used to follow the evolution in texture due to the applied loads. The most outstanding texture component, which was seen in the case of increased feed rate, is closely followed by the texture evolution model. The observed discrepancy in experimental and computational results of texture evolution in a few studied cases is believed to be due to the activation of other microstructural evolution phenomena rather than dislocation slip, as a result of the ultra-high levels of exerted strain and strain rates to the machined surface. [ABSTRACT FROM AUTHOR]

OBJECTIVE: G protein-coupled receptor, family C, group 6, member A, (GPRC6A) is a prostate cancer (PCa) susceptibility gene and has been shown to regulate PCa progression. However, its role in PCa metastasis is largely unknown. The aim of this study was to confirm the association between GPRC6A and aggressive PCa in a case-control analysis, and to explore the function of GPRC6A in PCa metastasis in vitro. PATIENTS AND METHODS: The association of 14 single nucleotide polymorphisms (SNPs) of GPRC6A and linked to GPRC6A were evaluated with PCa risk and aggressive PCa in 916 subjects. Metastasis behavior was determined in GPRC6A knockdown PC3 cells, and the expressions of matrix metalloproteinase (MMP)2 and MMP9 were detected. Bone transcription factor runt-related transcription factor 2 (RUNX2) and epithelial-mesenchymal transition (EMT) marker genes were examined in the GPRC6A overexpression PC3 cells. RESULTS: Among the 14 SNPs tested in PCa patients and controls, 4 were associated with aggressive PCa (p = 0.032-0.037, odds ratio = 1.38-1.41). Both the migration and invasion abilities were reduced in PC3 cells that were transiently transfected with GPRC6A short interfering RNA (siRNA). The GPRC6A knockdown cells showed reduced activity levels of MMP2 and MMP9. Furthermore, RUNX2, EMT and ERK signaling were shown to be up-regulated in GPRC6A overexpression cells. CONCLUSIONS: These findings suggest that GPRC6A is associated with aggressive PCa. GPRC6A knockdown inhibits the PCa cells migration and invasion, and GPRC6A overexpression promotes the EMT. It is suggested that GPRC6A may serve as a potential therapeutic target for metastatic PCa. [ABSTRACT FROM AUTHOR]

The understanding of cutting temperature distribution at the presence of tool wear can aid in addressing important metal cutting issues such as part surface integrity, tool life and dimensional tolerance under practical operating conditions. The effect of tool wear on the cutting temperature distribution was first modelled by Chao and Trigger and there have been very few followers since. In Chao's model, the primary heat source was assumed to have no effect on the workpiece temperature rise and the chip temperature rise was treated as a bulk quantity. This paper analytically quantifies the tool wear effect by taking into account the contributions of the primary heat source and considering the distribution of chip temperature rise. On the chip side, the primary shear zone is modelled as a uniform moving oblique band heat source and the secondary shear zone as a non-uniform moving band heat source within a semi-infinite medium. On the tool side, the effects of both the secondary and the rubbing heat sources are modelled as non-uniform static rectangular heat sources within a semi-infinite medium. For the workpiece side, the study models the primary shear zone as a uniform moving oblique band heat source and the rubbing heat source as a non-uniform moving band heat source within a semi-infinite medium. The proposed model is verified based on the published experimental data in the orthogonal cutting of Armco iron. Furthermore, a comparison case is presented on the temperature variation with respect to cutting speed, feed rate and flank wear length. [ABSTRACT FROM AUTHOR]

The reliability of a bearing is typically established by repeated life testing which provides valuable information on the fatigue mechanisms from crack initiation, crack propagation to flake or spall. Under nominal operating conditions, life testing often consumes a significant amount of time and resources, due to the comparatively high bearing mean lifetime before failure (M TBF), rendering the procedures expensive and impractical. Therefore, the technology of accelerated life testing (ALT), which is widely used in manufacturing practice, offers the attractive benefit of requiring relatively less investment in terms of time and resources. Data from tests at high stress levels (e.g. temperature, voltage, pressure, corrosive media, etc.) can be extrapolated, through a physically reasonable statistical model, to obtain life estimates at lower, normal stress levels. In this study, a methodology to predict bearing lifetime under a corrosive environment has been developed based on accelerated life testing data and the application of the inverse power law. Bearing life tests under various corrosion stress levels were performed for model identification followed by additional independent bearing life tests conducted for model verification. The experimental result shows that the accelerated life test model can effectively assess the life probability of a bearing based on accelerated environmental testing, even with extrapolation to untested stress levels. [ABSTRACT FROM AUTHOR]

Bearing condition monitoring has been the focus of a wide range of studies over the past years. Current monitoring techniques that focus on the identification of faults present in a bearing have various limitations. Typically they are applicable only under well-defined, specific and precalibrated operating conditions, thereby preventing continuous monitoring of a system operating in a variant environment. They are often limited in damage severity estimation and prognostic capability. This, in turn, prevents the development of optimal maintenance scheduling in favour of overall system safety and productivity. Research presented in this paper has yielded results that have extended bearing diagnostics and prognostics to address these limitations and to achieve optimal machinery maintenance scheduling. This paper discusses the current research status on the development of a new signal processing method with noise cancellation capability to provide early defect detection, the establishment of a diagnostic model to estimate bearing defect severity under variant conditions and the formulation of an adaptively tuned defect propagation model to track the time-variant nature of defect growth for the forecasting of bearing remaining utility. [ABSTRACT FROM AUTHOR]

Discusses the identification of cutter axis tilt in end milling process via cutting force analysis. How does cutter axis tilt operates; Description of the mathematical representation of chip thickness variation as a result of tilt; Estimation of tilt magnitude and orientation.

PURPOSE: Given the likely proliferation of targeted testing and treatment strategies for cancer, a better understanding of the utilization patterns of human epidermal growth factor receptor 2 (HER2) testing and trastuzumab and newer gene expression profiling (GEP) for risk stratification and chemotherapy decision making are important. STUDY DESIGN: Cross-sectional. METHODS: We performed a medical record review of women age 35 to 65 years diagnosed between 2006 and 2007 with invasive localized breast cancer, identified using claims from a large national health plan (N = 775). RESULTS: Almost all women received HER2 testing (96.9%), and 24.9% of women with an accepted indication received GEP. Unexplained socioeconomic differences in GEP use were apparent after adjusting for age and clinical characteristics; specifically, GEP use increased with income. For example, those in the lowest income category (< $40,000) were less likely than those with an income of $125,000 or more to receive GEP (odds ratio, 0.34; 95% CI, 0.16 to 0.73). A majority of women (57.7%) with HER2-positive disease received trastuzumab; among these women, differences in age and clinical characteristics were not apparent, although surprisingly, those in the lowest income category were more likely than those in the high-income category to receive trastuzumab (P = .02). Among women who did not have a positive HER2 test, 3.9% still received trastuzumab. Receipt of adjuvant chemotherapy increased as GEP score indicated greater risk of recurrence. CONCLUSION: Identifying and eliminating unnecessary variation in the use of these expensive tests and treatments should be part of quality improvement and efficiency programs.

Life testing under nominal operating conditions of mechanical parts with high mean lifetime between failure (MTBF) often consumes a significant amount of time and resources, rendering such procedures expensive and impractical. As a result, the technology of accelerated life testing (ALT) has been developed for testing at high stress levels (e.g. temperature, voltage, pressure, corrosive media, load, vibration amplitude, etc.) so that it can be extrapolated—through a physically reasonable statistical model—to obtain estimations of life at lower, normal stress levels or even limit stress levels. However, the issue of prediction accuracy associated with extrapolating data outside the range of testing, or even to a singularity level (no stress), has not yet been fully addressed. In this research, an accelerator factor is introduced into an inverse power law model to estimate the life distribution in terms of time and stresses. Also, a generalized Eyring model is set up for singularity extrapolation in handling limit stress level conditions. The procedure to calibrate the associated shape factors based on the maximum likelihood principle is also formulated. The methodology implementation, based on a one-main-step, multiple-step-stress test scheme, is experimentally illustrated with tapered roller bearing under the stress of environmental corrosion as a case study. The experimental results show that the developed accelerated life test model can effectively evaluate the life probability of a bearing based on accelerated testing data when extrapolating to the stress levels within or outside the range of testing. [Copyright &y& Elsevier]