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This article presents a new defected ground structure (DGS) and expands its application for designing high‐performance bandpass filters based on substrate integrated waveguide (SIW) platform. The presented DGS is consisted of two complementary stepped‐impedance E‐shaped structures and placed them together face‐to‐face. Such designed DGS is inserted into the top layer of a millimeter‐wave SIW to act as high‐frequency stopping property. Based on the proposed DGS, two high‐performance SIW bandpass filters with single‐band and dual‐band features are achieved, by fabricating prototypes and experimentally investigating the filtering performances. Good agreements between the simulations and experiments are obtained. Such proposed SIW bandpass filters based on the designed new DGS can be widely used in the upcoming 5G communication area. [ABSTRACT FROM AUTHOR]

The management of patients with triple‑negative breast cancer is challenging due to the lack of effective therapeutic options, aggressive behavior and relatively poor prognosis. Xi Huang pills (XHP) are a well‑known traditional Chinese medicine that demonstrate anticancer activities. The aim of the present study was to investigate the antitumor effects of XHP on MDA‑MB‑231 cells in vitro and in vivo, and its potential underlying molecular mechanisms. In the present study, an MTT assay was used to evaluate the antiproliferative activity of XHP on MDA‑MB‑231 cells. In order to investigate the effects further, cell cycle distribution, apoptosis and mitochondrial membrane potential assays were performed, as well as western blot analyses. In addition, a tumor xenograft model was employed to investigate the effects of XHP in vivo. The results of the MTT assay demonstrated that the viability of MDA‑MB‑231 cells was markedly inhibited by XHP in a dose-and time‑dependent manner. The inhibitory effect of XHP on the viability of MDA‑MB‑231 cells was greater when compared with MCF‑10A cells. An increase in apoptosis and loss of mitochondrial membrane potential was observed following 4, 8 and 12 mg/ml XHP treatment of MDA‑MB‑231 cells. The protein expression levels of cleaved caspase‑3 were increased by 1.62‑, 2.13‑ and 2.19‑fold, respectively, when compared with the untreated controls, whereas no effects on the expression of B‑cell lymphoma 2 (Bcl‑2) or Bcl‑2‑associated X protein (Bax) were observed. The results of the cell cycle distribution assay analysis demonstrated that XHP treatment arrested cells at the G2/M phase. In addition, XHP treatment decreased the expression of cyclin A and increased the expression of p21Cip1. In vivo experiments revealed that XHP inhibited the growth of MDA‑MB‑231 xenograft tumors without body weight loss, and demonstrated similar effects on the protein expression levels of cleaved caspase 3, cyclin A and p21Cip1 as observed in vitro. In conclusion, the viability of MDA‑MB‑231 cells was inhibited by XHP in a dose‑dependent, time‑dependent and cell‑selective manner in vitro, and the potential underlying mechanisms may involve apoptosis and cell cycle arrest at the G2/M phase. XHP may induce apoptosis in MDA‑MB‑231 cells via the intrinsic pathway, which does not involve the Bcl‑2/Bax ratio. G2/M phase arrest may have been due to the integrated action of decreased cyclin A expression and increased p21Cip1 expression. In addition, XHP inhibited the growth of xenograft tumors in the absence of body weight loss in vivo. [ABSTRACT FROM AUTHOR]

Deep learning techniques have received much attention in the area of image denoising. However, there are substantial differences in the various types of deep learning methods dealing with image denoising. Specifically, discriminative learning based on deep learning can ably address the issue of Gaussian noise. Optimization models based on deep learning are effective in estimating the real noise. However, there has thus far been little related research to summarize the different deep learning techniques for image denoising. In this paper, we offer a comparative study of deep techniques in image denoising. We first classify the deep convolutional neural networks (CNNs) for additive white noisy images; the deep CNNs for real noisy images; the deep CNNs for blind denoising and the deep CNNs for hybrid noisy images, which represents the combination of noisy, blurred and low-resolution images. Then, we analyze the motivations and principles of the different types of deep learning methods. Next, we compare the state-of-the-art methods on public denoising datasets in terms of quantitative and qualitative analyses. Finally, we point out some potential challenges and directions of future research. [ABSTRACT FROM AUTHOR]

The low hydraulic efficiency of the pump as turbine (PAT) poses a major challenge to the runner design. This paper introduces a new strategy for designing and optimizing the performance of PAT runner. The strategy process is mainly divided into four steps, namely blade parametric design, significance evaluation of parameters, construction of optimizing surrogate model and optimization of improved PSO algorithm. Compared with the current design methodologies, not only does this optimization strategy propose the system design and optimization process, but also it breaks down the process into well-defined steps and simplifies them. The hydraulic efficiency of PAT optimized by this optimization strategy reaches 84.76%, which improves 3.93%. A test bench has been built to test the optimizing strategy. The maximum difference of experimental data is 1.5%, which meets the requirements of practical engineering application, and verifies the reliability of the optimization strategy process. The optimizing strategy process can be extended to apply to pump, fan, conventional turbine and other blade fluid models, and it can be further extended to apply to the optimization design of 3D blades with a high specific speed. [Display omitted] [ABSTRACT FROM AUTHOR]

A double-row liquid–vapor separation microchannel condenser (D-LSMC) was presented, and its tube pass scheme was optimized using the theoretical method. A series of experiments were conducted to investigate the heat load, average heat transfer coefficient (AHTC), and pressure drop of the optimal D-LSMC. Experimental results were compared with an optimal common double-row parallel-flow microchannel condenser (D-PFMC). The findings showed that, at the inlet mass flux of 585 kgm −2  s −1 to 874 kgm −2  s −1 , the AHTC of the D-LSMC was 3.3%–14.4% higher than that of the D-PFMC. However, the pressure drop of the D-LSMC was only 43.4%–52.1% of that of the D-PFMC. The heat exchange capacity of the back row was weaker by almost half of that of the front row. In addition, the tube wall temperature of the back row decreased faster than that of the front row, which indicated that the back row had a larger pressure drop. The minimum entropy generation number (Ns) was used to evaluate the D-LSMC and the D-PFMC, which indicated the greater thermodynamic performance of the D-LSMC. [ABSTRACT FROM AUTHOR]

This study evaluates the thermal hydraulic performance of a novel liquid–vapor separation condenser (LSC). A series of experiments was performed to investigate the in-tube heat transfer coefficient and pressure drop of the LSC with varying average refrigerant quality at constant mass flux. The results were compared with the performance of a serpentine condenser (SC) and a parallel-flow condenser (PFC), with R134a as the refrigerant. Findings showed a very small change in the wall temperature of the LSC. The LSC had the lowest average condensation heat transfer coefficient among the three condensers at lower heat flux, but exceeded that of the PFC at higher heat flux. The pressure drop of the LSC was 77.1–81.4% lower than that of the SC and 57.5–64.6% lower than that of the PFC at a heat flux of 6.45 kWm − 2 . Moreover, heat flux and condensing temperature had little influence on the pressure drop of the LSC. Based on these experimental data, the three evaluation criteria (friction power ratio, penalty factor, and minimum entropy generation number) applied to the three condensers proved that the LSC had the best thermal hydraulic performance. The lowest irreversibility of the LSC resulted from the entropy generation rate of the refrigerant side, which was the lowest among the three condensers. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposed a computation program to predict the in-tube thermodynamic performance of the LSC (liquid–vapor separation condenser). The refrigerant circuit of the LSC was then optimized using the Penalty Factor with the predicted results. The proposed program was used to calculate a case and an optimized tube pass strategy was obtained under a fixed condition. Higher heat transfer coefficient and lower pressure drop appeared in a number of LSCs compared with an equivalent serpentine condenser under the same operating conditions. To verify the results of the proposed program, a group of corresponding experiments were conducted to measure the heat transfer and pressure drop of the LSC using the optimized circuit strategy. The results from most experimental data demonstrated that both heat transfer coefficient and pressure drop fell into the range of ±30%. [Copyright &y& Elsevier]