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A reflection approach utilizing an open-ended rectangular waveguide (ORW) for dielectric constant characterization of low-loss slab materials is presented. A calibration technique is proposed to reduce the effects of the higher order mode fields in dominant-mode analysis. In addition, the effects of undesired reflections caused by the finite-sized flange are also reduced in the extraction of the dielectric constant. Moreover, a small perturbation is introduced in the calculation of the reflection coefficient to eliminate the singularities as well. The dielectric constant of material under test (MUT) is extracted utilizing the measured reflection coefficient by assuming that the loss tangent of MUT is zero. Simulation results are presented to validate the calibration process. The selection of suitable airgap thickness and the effects of lossy MUT are also discussed. The measured dielectric constants of MUT made of polymethyl methacrylate (PMMA) and polytetrafluoroethylene (PTFE) are presented as well, which agrees excellently with the results achieved from the free-space method.

Currently, revealing how to prevent and control hyperuricemia has become an essential public health issue. Sulforaphane hasawiderangeofapplications in the management of hyperuricemia.The study objective was to verify the uric acid-lowering effects and the regulation of the gut-kidney axis mediated by sulforaphane and identify host-microbial co-metabolites in hyperuricemia.A hyperuricemia model was established by administering feedstuffs with 4% potassium oxonate and 20% yeast. Forty male Sprague-Dawley rats were randomly divided into the normal control, hyperuricemia, allopurinol, and sulforaphane groups. Animals were treated by oral gavage for six consecutive weeks, and then phenotypic parameters, metabolomic profiling, and metagenomicsequencing were performed.Sulforaphane could lower uric acid by decreasing urate synthesis and increasing renal urate excretion in hyperuricemic rats (P＜0.05). We identified succinic acid and oxoglutaric acid as critical host-gut microbiome co-metabolites. Moreover, sulforaphane improved the diversity of microbial ecosystems and functions, as well as metabolic control of the kidney. Notably, sulforaphane exerted its renoprotective effect through epigenetic modification of Nrf2 and interaction between gut microbiota and epigenetic modification in hyperuricemic rats.We revealed that sulforaphane could ameliorate the progression of hyperuricemia by reprogramming the gut microbiome and metabolome. Our findings may provide a good means for efficiently preventing and treating hyperuricemia.

To investigate the behavior of plasma generated in the shock tube, microwave reflectometry is proposed to extract the permittivity $\epsilon _{r}$ of plasma. To remove the influence of parasitic reflections caused by the surroundings, a calibration process is introduced and the unknown calibration coefficients are determined by utilizing microwave interferometry as the reference technique. The shock tube is modeled as a three-layered medium to calculate the reflection coefficient. A time-dependent reconstruction algorithm is applied and theoretically validated to eliminate the multiple solutions in the inverse problem. By comparing the permittivities extracted with microwave reflectometry and interferometry, the effects of plasma diffusion are demonstrated with a modified analytical model in the beginning time region of experiments. In addition, the nonuniform flow in the generated plasma located near the end time region is also observed. The determination of the effective time region for electron density $N_{e}$ and collision frequency $v_{e}$ extraction is discussed as well. Finally, the differences between microwave reflectometry and interferometry in terms of averaged $N_{e}$ < $1{\times }10^{17} m^{-3}$ and averaged $v_{e}$ < $1.5{\times }10^{9} s^{-1}$ are investigated in the effective time region

Nowadays, developing effective intervention substances for hyperuricemia has become a public health issue. Herein, the therapeutic ability of anserine, a bioactive peptide, was validated through a comprehensive multiomics analysis of a rat model of hyperuricemia. Anserine was observed to improve liver and kidney function and modulate urate-related transporter expressions in the kidneys. Urine metabolomics showed that 15 and 9 metabolites were significantly increased and decreased, respectively, in hyperuricemic rats after the anserine intervention. Key metabolites such as fructose, xylose, methionine, erythronic acid, glucaric acid, pipecolic acid and trans-ferulic acid were associated with ameliorating kidney injury. Additionally, anserine regularly changed the gut microbiota, thereby ameliorating purine metabolism abnormalities and alleviating inflammatory responses. The integrated multiomics analysis indicated that Saccharomyces, Parasutterella excrementihominis and Emergencia timonensis were strongly associated with key differential metabolites. Therefore, we propose that anserine improved hyperuricemia via the gut–kidney axis, highlighting its potential in preventing and treating hyperuricemia.

At present, uncovering how to preventandcontrol hyperuricemia has become an important public health issue. Fermented traditionalChinesemedicine has exhibited promising applications in the clinical management of hyperuricemia. In this study, we generated a hyperuricemic mouse model to explore the potent therapeutic ability of Bacillus subtilis-fermented Astragalus membranaceus (BFA) on this condition by multi-omics analysis. We found that the serum uric acid level was decreased in hyperuricemic mice after BFA treatment. BFA effectively attenuated renal inflammation and regulated the expression of urate transporters. Additionally, we found that BFA could increase the abundances of butyrate-producing bacteria, including Butyricimonas synergistica, Odoribacter splanchnicus, and Collinsella tanakaei, and probiotics, including Lactobacillus intestinalis and Bacillus mycoides, in hyperuricemic mice. Therefore, we believe that BFA has the potential to become a novel safe and valid functional food for addressing hyperuricemia.

Objective: To understand the reason for low implementation of clinical and home-based rehabilitation robots and their potential.Design: Online questionnaire (November 2020 and February 2021).Subjects: A total of 100 professionals in stroke rehabilitation area were involved (Physiotherapists n = 62, Occupation therapists n = 35).Interventions: Not applicable.Main Measures: Descriptive statistics and thematic content analysis were used to analyze the responses: 1. Participants' details, 2. Professionals' views and experience of using clinical rehabilitation robots, 3. Professionals' expectation and concerns of using home-based rehabilitation robots.Results: Of 100 responses, 37 had experience of rehabilitation robots. Professionals reported that patients enjoyed using them and they increased accessibility, autonomy, and convenience especially when used at home. The main emergent themes were: “aims and objectives for rehabilitation robotics,” “requirements” (functional, software, and safety), “cost,” “patient factors” (contraindications, cautions, and concerns), and “staff issues” (concerns and benefits). The main benefits of rehabilitation robots were that they provided greater choice for therapy, increased the amount/intensity of treatment, and greater motivation to practice. Professionals perceived logistical issues (ease of use, transport, and storage), cost and limited adaptability to patients' needs to be significant barriers to tier use, whilst acknowledging they can reduce staff workload to a certain extent.Conclusion: The main reported benefit of rehabilitation robots were they increased the amount of therapy and practice after stroke. Ease of use and adaptability are the key requirements. High cost and staffing resources were the main barriers.

Robotic-assisted therapy is a well-studied method for post-stroke upper limb rehabilitation demonstrating improvements in arm function. The majority of rehabilitation robots are designed for clinical settings to which it is challenging for patients to travel to receive adequate amounts of therapy. One solution is home-based rehabilitation robots which can enable patients to engage with intensive and frequent useful therapy. Nowadays, most home-based upper limb rehabilitation robots promote planar movement, while the motion of upper limb is a three-dimensional movement in daily life. The aim of this paper is therefore, to design and optimize a conceptual design which is suitable for the home environment with three-dimensional movement promotion. Firstly, the mechanical structure of this robot is presented; secondly, the kinematic analysis of this robot is introduced and the workspace is simulated by MATLAB; finally, the topology optimization is used to reduce the robot mass while keeping the strength and stiffness. The total estimated mass of the robot has been reduced from 14.9Kg to 12.5Kg, a reduction of 15.7% of the original design. This research presents a novel lightweight home-based upper limb rehabilitation robot with 4 degrees of freedom, which provides a suitable solution for home-based rehabilitation. This research demonstrates the potential of topology optimization combined with additive manufacturing techniques to reduce the mass of home-based rehabilitation robots a key design requirement.

Social VR has been widely promoted and popularized in recent years. Due to the immersion characteristic of VR, although people do not have physical contact in the virtual space, they still have judgements on distance and may feel annoyed when their personal space is intruded. Social VR users want to communicate with their virtual friends in the space. Meanwhile, keep a comfortable distance from other avatars and protect their personal space. In this paper, we evaluate user’s perception and comfortable level of personal distance and compare four different methods to protect personal space in social VR.

In a modern Intelligent Transportation System (ITS), traffic prediction exerts an enormous function in alleviating traffic congestion and path planning. Due to the complex dynamic spatial-temporal dependence of traffic data, the traditional prediction methods have some limitations in the spatial-temporal correlation modeling, and cannot effectively predict both long-short term traffic conditions. In this paper, a novel deep learning framework Spatial-Temporal Graph Wavelet Attention Neural Network (ST-GWANN) is proposed for long-short term traffic prediction, which can comprehensively capture the spatial-temporal features. In the framework, the graph wavelet neural network and attention mechanism are integrated into the spatial gated block, which can obtain the spatial dependence of the road network. By combining the Gated Linear Units (GLU) and the temporal transformer layer, the local and global dependence of the time dimension are obtained. The proposed framework experimented on two real-world datasets, the results show that ST-GWANN outperforms state-of-art methods in traffic prediction tasks.

The time-varying property of traffic networks has brought a problem of modeling large-scale dynamic networks. Based on the real-time traffic sensing data of the road network, community division and prediction can effectively reduce the complexity of local management in urban regions. However, traffic-based communities have complex topology and real-time dynamic features, and traditional community division and topology prediction cannot effectively be applied to this structure. Therefore, we propose a dynamic traffic community prediction model based on hierarchical graph attention network. It uses the hierarchical features fusion with spatiotemporal convolution and the ADGCN proposed in this paper to compose a hierarchical graph attention architecture. In which, each layer component coordinates to perform different features extraction for capturing traffic community of road network in different time periods respectively. Finally, the output features of each layer are combined to represent the dynamically divided regions in the traffic network. The effectiveness of the model was verified in experiments on the Xi'an urban traffic dataset.

Background: Home-based robotic therapy is a trend of post-stroke upper limb rehabilitation. Although home-based upper limb rehabilitation robots have been developed over several decades, no design specification has been published. Objectives: To identify and synthesize design requirements considering user and technology needs for a home-based upper limb rehabilitation robot through a scoping review. Method: Studies published between 1 January 2000 and 10 June 2020 in Scopus, Web of Science and PubMed database regarding design requirements for upper limb rehabilitation robots from of stroke survivors or therapists were identified and analyzed. We use 'requirement' as something that is needed or wanted. Two physiotherapists ranked the requirements identified from literature review. Results: Nine studies were selected for review. They identified 42 requirements regarding functionality (n = 11, 26.2% of total requirements), usability (n = 16, 38.0% of total requirements), software (n = 14, 33.3% of total requirements) and safety (n = 1, 2.4% of total requirements). The main implementation barriers with respect to adherence and monitoring were space, operation, and cost. Conclusion: This is the first research to summarize the design requirements for home-based upper limb rehabilitation robots for stroke survivors. The need for a safe, comfortable, easy to use device which can be individualized and promote specific movements and tasks emerged. The result of this paper captures the design requirements that can be used in future for the development of a design specification. It provides designers and researchers guidance about the real-world needs for home-based upper limb rehabilitation robots for stroke.

A non-interventional plasma diagnosis method based on millimeter transmission theory over W-band is proposed in this paper. The attenuation and phase change of electromagnetic wave through plasma were measured by the w-band transmission measurement system. The transient change curves of electron density and collision frequency in the shock tube are obtained by the test data. Moreover, the effects of air pressure and the speed of shock wave on the plasma are analyzed.

A switchable rasorber with high selectivity is proposed. The rasorber is composed of a frequency selective surface (FSS) and a resistive layer. Both FSS and resistive layers are loaded with a PIN diode. When diodes are turned off, a low loss transmission band between two absorption bands is obtained. When diodes are turned on, the transmission band is closed, making the rasorber into an absorber. A Third-order FSS is adopted to enhance the selectivity of the transmission band. The proposed switchable rasorber can be used to design the smart radome.

In this paper, a super Wadati-Konno-Ichikawa (WKI) hierarchy associated with a 3×3 matrix spectral problem is derived with the help of the zero-curvature equation. We obtain the super bi-Hamiltonian structures by using of the super trace identity. Infinitely, many conserved laws of the super WKI equation are constructed by using spectral parameter expansions.

This work presents a millimeter-wave transceiving systems for the investigation of plasma in shock tube. To deal with the supersonic plasma shock wave, the system utilizes a high-speed analog-to-digital (ADC) converter to improve the time resolution. In addition, a high dynamic range is also designed for the system to extend the measurement range of plasma electron density. The measured amplitude and phase of the reflection measurement demonstrates the effects of plasma in shock tube, which can be utilized to investigate the mm-wave properties of plasma.

A microwave reflection method is presented to determine the complex permittivity of time-varying plasma. Due to the existing of multiple solutions in the extraction of permittivity from reflection coefficient, a linear variation approximation is proposed with two unknown timing coefficients to be defined with the Simplex algorithm. At last, the measurement results of shock-tube excited plasma are presented.

In this paper, the performance of a new dual-band Frequency Selective Surface (FSS) structure based on square ring and three-pole loading was presented. Two applications which were carried out to verify the feasibility of the FSS structure are using the FSS as the high impedance surface to design absorbing material and as the radome to reduce the antenna Radar Cross Section (RCS). The wave-transparent rate of the FSS is given when a plane wave is incident at some angle. Simulation results shows that the performance of the FSS is stable. In the first application, the absorbing material only designed with the FSS structure and FR4 is thinner than the traditional absorbing material, and the total thickness is low to 3.6 mm. Bandwidth of the artificial electromagnetic material (the absorptivity is more than 80%) is nearly 5.2%. Frequency Selective Radome not only can reduce the RCS, but also can resist external interference to maintain a good working environment for antenna. In the following content, we build an ideal model of antenna and radome system to discuss the influence of the Frequency Selective Radome on the conformal antenna. The results of RCS and antenna performance were compared between cylindrical conformal antenna array with radome or not. It's worth noting that the FSS radome has little effect on the performance of conformal antenna array, moreover it has a significant RCS reduction in pass band. Simulation results show that the FSS can be used to design efficient electromagnetic absorber and radome that all can be applied in RCS reduction.

The paper uses Analytical Hierarchy Process(AHP) to analyze the primary elements that affect the country's textile and garment export.Then the target market of China's textile and garment export trade is determined.Then it can have the referential meaning and application value to ourcountry's textile and garment export enterprises and departments which may do scientific decisions.

A microwave reflection measurement method is proposed to determine the dielectric constant of dielectric slabs without knowing their exact thickness. The expression of dielectric constant is derived according to the transmission line theory, in which the loss of material is neglected. Error analysis for lossy dielectric slabs has also been conducted. In-house measurement results on commercial polymethyl methacrylate, polytetrafluoroethylene, and FR4 samples have been presented to validate the proposed method. Excellent agreement has been achieved between the proposed method and the conventional free-space method. The proposed method is suitable for the dielectric constant characterization of thin-slab materials with low loss and low dielectric constant.

Plasma has been of great interest to engineers and scientists during the past few decades due to its wide applications. Besides, the plasma-sheath-caused lose of communication (i.e. re-entry blackout) that happens when a spacecraft re-enters the earth atmosphere is still a problem to be solved. The microwave characterisation of shock tube excited plasma has been an important method for exploring the transmission and reflection of microwave signals in plasma. The existing frequency sweep or multi-frequency technologies are not desirable for the characterisation of high-speed time-varying plasma generated in shock tubes. Hence, in this paper a novel signal-frequency approach is proposed to measure both electron density and collision frequency of plasma in shock tube. As frequency sweep is not required in this method, it is extremely suitable for characterising the shock tube excited high-speed time-varying plasma. The genetic algorithm is applied to extract electron density and collision frequency from the reflection coefficient. Simulation results demonstrate excellent accuracy for electron density within 1 0 10 ∼ 1 0 12 c m − 3 and collision frequency within 5 × 1 0 10 ∼ 1 0 12 H z . This work paves the way for a fast and compact microwave reflection measurement of shock tube generated plasma.