Telesurgery QoS improvement over SDN based on a Type‐2 fuzzy system and enhanced cuckoo optimization algorithm

Telemedicine is a new area based on the information and communication technology for collecting, storing, organizing, retrieving and exchanging medical information. One of the most important applications of telemedicine is indeed telesurgery in which an efficient telecommunication infrastructure between the surgery room and remote surgeons need to be established. One of the most important issues to be tackled in telesurgery is to find favorable links for routing as well as providing high Quality of Service (QoS). In this paper, an efficient model based on the hybridization of Type‐2 Fuzzy System (T2FS) and Cuckoo Optimization Algorithm (COA) over the Software Defined Networks (SDN) is proposed in order to achieve optimal and reliable routes for telesurgery application. Using T2FS, the fitness of the links is determined; then, a COA is conducted over the Constraint Shortest Path (CSP) problem to find the best routes. Delay is considered as a CSP problem which is satisfied by trying to find the paths with minimum cost. Due to the NP‐completeness of the CSP problem, an Enhanced COA (so‐called E‐COA) is proposed and utilized as a metaheuristic solver. To the best of our knowledge, this paper is the first SDN‐based communication model that applies both T2FS and E‐COA for assigning proper costs to the network's links, and solves the consequence CSP problem according to the QoS requirement for telesurgery. The model also recognizes and preserves the second‐best routes in order to keep the reliability for such a critical application. In addition to the simulations, the performance evaluation is also conducted on a real experimental scenario. Many comparisons are carried out between the proposed model and other conventional methods, and the evaluation study shows the superiority of the proposed model on all the three QoS‐related metrics, i.e. average end‐to‐end delay, packet loss ratio and PSNR.     

Kahweol inhibits adipogenesis of 3T3-L1 adipocytes through downregulation of PPARγ

Kahweol, a compound from Coffea arabica, possesses antioxidant, anti-inflammatory, and antitumour properties. However, an anti-adipogenic effect has not yet been reported. In this study, we have shown that kahweol has an anti-adipogenic effect on 3T3-L1 adipocytes. Kahweol significantly inhibited the differentiation of intracellular lipid accumulation in 3T3-L1 adipocytes, without being cytotoxic. It also downregulated the expression of adipogenesis-related gene, including an adipocytokine, adiponectin. This anti-adipogenic effect stems from an ability to inhibit key adipogenic regulators, including PPARγ and C/EBPα. These results demonstrate that kahweol significantly inhibits the differentiation of 3T3-L1 cells, and suggest that it has potential as a novel anti-obesity treatment.     

Using random forest to classify T-cell epitopes based on amino acid properties and molecular features

T-lymphocyte (T-cell) is a very important component in human immune system. T-cell epitopes can be used for the accurately monitoring the immune responses which activation by major histocompatibility complex (MHC), and rationally designing vaccines. Therefore, accurate prediction of T-cell epitopes is crucial for vaccine development and clinical immunology. In current study, two types peptide features, i.e., amino acid properties and chemical molecular features were used for the T-cell epitopes peptide representation. Based on these features, random forest (RF) algorithm, a powerful machine learning algorithm, was used to classify T-cell epitopes and non-T-cell epitopes. The classification accuracy, sensitivity, specificity, Matthews correlation coefficient (MCC), and area under the curve (AUC) values for proposed method are 97.54%, 97.22%, 97.60%, 0.9193, and 0.9868, respectively. These results indicate that current method based on the combined features and RF is effective for T-cell epitopes prediction.     

直觉I-Fuzzy拓扑空间的杨忠道定理

以L~*-格值上Lukasiewicz蕴含算子为工具引入了直觉I-Fuzzy拓扑空间中导集概念,接着给出它的一些性质,最后证明了直觉I-Fuzzy拓扑空间中导集的杨忠道定理.     

Concentration Dependence of NMR T1 in Agar Solutions

In this study, in order to explain solvent proton relaxation mechanism, the spin-lattice relaxation time (T1) of agar solutions was measured as a function of agar concentration. Relaxation measurements were carried out by a FT-NMR spectrometer operating at 60 MHz and inversion recovery pulse squence was used. Relaxation rate(1/T1a) was linearly proportional to concentration of agar solution (C), and the T1 mechanism of solvent water protons in agar solutions should be caused by the chemical exchange of water protons between free and bound water.     

Powder‐XRD and 14N magic angle‐spinning solid‐state NMR spectroscopy of some metal nitrides

Some metal nitrides (TiN, ZrN, InN, GaN, Ca₃N₂, Mg₃N₂, and Ge₃N₄) have been studied by powder X‐ray diffraction (XRD) and ¹⁴N magic angle‐spinning (MAS) solid‐state NMR spectroscopy. For Ca₃N₂, Mg₃N₂, and Ge₃N₄, no ¹⁴N NMR signal was observed. Low speed (ν_r = 2 kHz for TiN, ZrN, and GaN; ν_r = 1 kHz for InN) and ‘high speed’ (ν_r = 15 kHz for TiN; ν_r = 5 kHz for ZrN; ν_r = 10 kHz for InN and GaN) MAS NMR experiments were performed. For TiN, ZrN, InN, and GaN, powder‐XRD was used to identify the phases present in each sample. The number of peaks observed for each sample in their ¹⁴N MAS solid‐state NMR spectrum matches perfectly well with the number of nitrogen‐containing phases identified by powder‐XRD. The ¹⁴N MAS solid‐state NMR spectra are symmetric and dominated by the quadrupolar interaction. The envelopes of the spinning sidebands manifold are Lorentzian, and it is concluded that there is a distribution of the quadrupolar coupling constants Q_cc's arising from structural defects in the compounds studied. Copyright © 2015 John Wiley & Sons, Ltd.     

Combined prostate diffusion tensor imaging and dynamic contrast enhanced MRI at 3T — quantitative correlation with biopsy

The purpose of this work was to compare diagnostic accuracy of Diffusion Tensor Imaging (DTI), dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) and their combination in diagnosing prostate cancer. Twenty-five patients with clinical suspicion of prostate cancer underwent MRI, prior to transrectal ultrasound-guided biopsies. MRI data were correlated to biopsy results. Logistic regression models were constructed for the DTI parameters, DCE MRI parameters, and their combination. The areas under the receiver operator characteristic curves (AUC) were compared between the models. The nonparametric Wilcoxon signed rank test was used for statistical analysis. The sensitivity and specificity values were respectively 81% (74–87%) and 85% (79–90%) for DTI and 63% (55–70%) and 90% (85–94%) for DCE. The combination “DTI or DCE MRI” had 100% (97–100%) sensitivity and 77% (69–83%) specificity, while “DTI and DCE MRI” had 44% (37–52%) sensitivity and 98% (94–100%) specificity. The AUC for DTI+DCE parameters was significantly higher than that for either DTI (0.96 vs. 0.92, P=.0143) or DCE MRI parameters (0.96 vs. 0.87, P=.00187) alone. In conclusion, the combination of DTI and DCE MRI has significantly better accuracy in prostate cancer diagnosis than either technique alone.     

直拉单晶炉减薄型加热器的数值模拟与实验分析

在直拉单晶炉中使用一种减薄型加热器替代原加热器,改变了单晶炉的热场温度分布。通过有限元模拟分析软件对减薄型加热器进行模拟分析,模拟结果指出减薄型加热器对提升单晶拉速、降低单晶炉功耗具有促进作用。通过对比两种加热器装料量,并进行单晶生长对比实验,实验指出,减薄型加热器在引晶、等径、收尾阶段均降低了功耗,提升了拉速。最后,数据分析指出减薄型加热器的经济性比原加热器有一定提升。     

一种基于波导E-T结的新型功分器的设计方法

针对传统功分器的不足,提出了一种改进型波导E-T结功分器。通过三维电磁仿真软件CST对其进行了建模仿真,得到一个合理的设计方案,该结构具有高隔离度、低插入损耗、小体积、宽频带等优点。加工的实物经测试在12~17 GHz的频率范围内,该功分器的插入损耗＜0.12 dB,回波损耗＞18 dB,隔离度＞15 dB,具有良好的工程应用价值。     

柔性薄膜收发组件技术研究

采用有源相控阵技术的薄膜合成孔径雷达因其全天候、大范围、高精度的探测能力,受到各国广泛重视。柔性薄膜T/ R 组件,由于其重量轻、厚度薄、可弯曲的特性,可以满足天基预警雷达柔性薄膜天线的需要。柔性 薄膜收发组件作为薄膜合成孔径雷达的核心部件,成为薄膜合成孔径雷达(SAR)的关键。文中对柔性薄膜T/ R 组件的接收和发射电路、弯曲特性进行了仿真分析,并对该T/ R 组件样机进行测试验证,获得了工作频段为L 波段,接收增益大于24dB,噪声系数小于2dB,发射功率大于1W,弯曲对带内的损耗影响小于0. 1dB,对带内的相位影响小于2°的结果,其在噪声和接收性能上具有先进性,并对工程应用具有一定的实际参考意义。