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In this letter, a broadband millimeter-wave (mm-wave) continuous-mode Class-F power amplifier (PA) based on the deembedded transistor model is proposed for the fifth-generation (5G) applications. To design the output matching network at the intrinsic current-generator plane, an $S$ -parameter fitting method is proposed to extract the parasitic parameters of nonpackaged transistors over a wide frequency range. The PA is implemented in the 0.13- $\mu \text{m}$ SiGe BiCMOS process, which occupies only 0.42 mm2. By controlling the even and odd harmonics impedance, the PA achieves a 78.2% −3-dB small-signal gain fractional bandwidth from 21.1 to 48.2 GHz. The −1-dB $P_{\mathrm {sat}}$ bandwidth covers 21–43 GHz (68.8% fractional bandwidth) and the saturated output powers are 17.2–18.1 dBm. Meanwhile, the designed PA provides a 24.1%–32.1% peak power-added efficiency (PAE) over the band.

Nonreciprocal components such as circulators, isolators, and gyrators play vital roles in modern communication systems. However, all of them are limited to 0.1 terahertz (THz) due to their poor performances in terms of linearity, loss, and noise at high frequency, making them not amenable for the potential sub-THz/THz operation. In this letter, a 210-GHz nonreciprocal isolator based on the resistor-free unidirectional ring resonators is implemented in a 130-nm SiGe BiCMOS process ( $f_{T}/f_{\mathrm {max}} = 300$ /500 GHz). Thanks to the proposed resistor-free ring resonators, the isolator achieves 1.40-dB loss, 6.7-dB noise figure (NF)/unit, 21.2-dB isolation, and superior linearity. Even compared with the nonreciprocal components operating at a much lower frequency, this structure also exhibits a good performance.

A positive feedback gain-enhanced technique for power amplifiers has been introduced in this Letter. With the proposed circuit design method for optimal inductive feedback, a 180 GHz high-gain single-stage cascode power amplifier in a 130 nm SiGe process is implemented. The measurement results show a power gain of 10 dB and 20 GHz bandwidth with 110 mW dc power are achieved, and 6.5 dBm of output power referred to P 1dB and 3.5% collector efficiency are attained. The chip area of the power amplifier is only 0.50 × 0.48 mm2.

In this work, we reported a nitrogen-doped porous carbon (NPC) that was prepared from waste polyurethane (PU) foams through hydrothermal carbonization and further activation. The possible reactions...

Background. Immune dysfunction can occur after neoadjuvant chemotherapy (NAC) and surgery for cancer. We investigated whether preoperative oral carbohydrate affected the postoperative percentages of T cells (CD4+ and CD8+) and natural killer (NK) cells in patients with cervical cancer treated with NAC and surgery. Methods. This prospective cohort study enrolled consecutive patients with cervical cancer treated by radical hysterectomy with PLND at the Gynecologic Oncology Department of Fujian Provincial Cancer Hospital (China) between January 2018 and December 2018. Patients were divided into three groups according to the treatment method: NAC (two cycles, surgery 1 month later), NAC+CHO (chemotherapy and surgical methods same as with the NAC group but with 300 mL of oral carbohydrate administered 2 h before surgery), and non-NAC (surgery alone). Percentages of NK, CD3+, CD4+, and CD8+ cells were evaluated by flow cytometry the day after the first admission, just before surgery, immediately after tracheal tube removal, and the day after surgery. This trial is registered with NCT03872635 at clinicaltrials.com. Results. The final analysis included 77 patients (non-NAC group, n=26; NAC group, n=25; and NAC-CHO group, n=26). Baseline characteristics and preoperative NK, CD3+, CD4+, and CD8+ cell percentages were similar between groups. Postoperatively, all groups exhibited reductions in NK, CD3+, and CD4+ cell percentages and increases in CD8+ cell percentages (all P<0.05). The changes in NK, CD3+, CD4+, and CD8+ cell percentages were attenuated in the NAC-CHO group (P<0.05 vs. both other groups). Conclusion. Preoperative oral carbohydrate can improve the postoperative populations of NK and T cells after the treatment of cervical cancer by NAC and surgery.

The finite element (FE) simulation is employed to predict the residual stresses, which is induced by the welding and the temperature alternating load. The simulation of 5A90 Al-Li alloy T-joint welded by the dual laser beam bilateral synchronous welding (DLBSW) is carried out. Then the evolution of the residual stresses is obtained under the temperature alternating load which is achieved by changing the ambient temperature on T-joint. In addition, the accuracy of simulation model has been verified by comparing the experimental results with the simulation results. According to the comparison, the simulation results are consistent with the experimental results, which shows that the residual stresses of 5A90 T-joints decrease under the temperature alternating load. Besides, the FE simulation is a relatively efficient and accurate method to predict the change of residual stresses under the temperature alternating load.

This study was aimed to investigate the influence of miR-33-5p on the M1/M2 polarization of microglia and the underlying mechanism. Transcriptome sequencing was performed using microglia from miR-33-5p mimic and control groups. In total, 507 differentially expressed genes, including 314 upregulated genes and 193 downregulated genes, were identified. The subnetwork of module A, which was extracted from the protein-protein interaction networks, mainly contained the downregulated genes.

The entrance section of the high-speed railway tunnel in southern China has been in a state of high temperature for a long time and is subject to alternating temperature changes. The surrounding rock is heterogeneous characteristics. Under a large temperature difference environment, temperature stress will occur between mineral particles and mineral particles. When the temperature stress is greater than the tensile strength of the surrounding rock, it will cause the rock to crack. In order to analyze the mechanism of the tunnel surrounding rock crack disease:(1)Based on thermoelastic mechanics and Weibull distribution, considering heterogeneous of the coefficient of thermal expansion(CTE) of mineral cells, an improved hightemperature initiation mechanical model of heterogeneous rock is established.(2)Aiming at the heterogeneous of thermal conductivity(TC) of mineral cells, the Agari series-parallel model is introduced to improve the thermal conductivity of the model.(3)By changing the degree of heterogeneous of CTE and TC, considering the joint action of the local temperature gradient of the rock, the macroscopic and mesoscopic laws of the initiation mechanism of rock are studied.(4)Analyze the maximum principal stress and crack initiation temperature regions of sandstone and granite through engineering calculation examples. The results show that with the continuous increase of temperature load, the internal stress of the rock continues to increase. Under the action of temperature load, the peak strength of the rock increases with the increase of the rock homogeneity coefficient. Local

Aedes albopictus (Skuse) is a vector of several arboviruses, such as dengue, chikungunya, West Nile, and Zika viruses. At present, the use of synthetic insecticides is the main vector control strategy. However, the widespread and long-term use of insecticides has aroused several problems, including insecticide resistance, environmental pollution, and non-target species effects, thereby encouraging researchers to search for new alternatives derived from natural products. In recent decades, essential oils (EOs) as natural alternatives to control mosquitoes have received increasing attention. In the initial larvicidal activity screen, two Rutaceae plants (Citrus aurantium and Citrus paradisi) EOs were selected and evaluated for killing Ae. albopictus larvae. The LC50 values of C. aurantium and C. paradisi EOs against Ae. albopictus were 91.7 and 100.9 ppm, respectively. The main components of C. aurantium EO include diethyl o-phthalate (37.32%), limonene (10.04%), and methyl dihydrojasmonate (6.48%). The main components of C. paradisi EO include limonene (60.51%), diethyl o-phthalate (11.75%), linalool (7.90%), and styralyl acetate (6.28%). Among these main components of the two EOs, limonene showed potent larvicidal activity, with the LC50 value of 39.7 ppm. The nanoemulsions of limonene were prepared and characterized. The duration of larvicidal activity was greater in the limonene nanoemulsions than when limonene was applied in solvent. This study demonstrates that EOs of plants in family Rutaceae are a potential resource to develop new larvicides, and nanoemulsification is an effective method for improving the physicochemical properties and efficacy of natural products as larvicides.

Refereed/Peer-reviewed Perfluorooctane sulfonate (PFOS) is a highly persistent contaminant of emerging concern causing harmful effects to human and ecosystem health. In this study, a novel MOF-808 metal–organic framework (MOF) was prepared and evaluated for adsorptive removal of PFOS from aqueous solution. The MOF-808 had high specific surface area (SSA; 1610 m²/g) and was structurally stable in aqueous medium for 7 days under different pH conditions. The MOF-808 reached PFOS adsorption equilibrium within 30 min (at 500 mg/L initial PFOS) and attained the maximum adsorption capacity of 939 mg/g at pH 4.1 – 5.4 (with 50 – 500 mg/L initial PFOS). The PFOS adsorption capacity of MOF-808 was unaffected at pH 2 to 7, but gradually decreased at pH > 7. High SSA, favorable pore size and abundant active adsorption sites on MOF-808 triggered high PFOS adsorption onto the adsorbent. The PFOS adsorption process was endothermic and spontaneous in nature. Electrostatic interaction between the cationic central cluster ([Zr₆O₄(OH)₄]¹²⁺) of MOF-808 and PFOS anion was identified as the key mechanism of PFOS adsorption onto MOF-808, as evident from the infrared spectroscopic investigation of the adsorbent. This study suggests that MOF-808 can be considered as a highly efficient adsorbent for PFOS removal from water and warrants future research to evaluate the application and performance of the material under wastewater conditions.

Speeding is one of the leading causes of traffic crashes worldwide. Radar velocimeter is widely used in the capture monitoring of road overspeed violations, which can effectively reduce the probability of traffic accidents and protect people’s life and property safety to the greatest extent. As a new type of radar velocimeter, multitarget radar velocimeter (MTRV) can monitor the speed of more than two vehicles at the same time. However, the verification method and device of MTRV’s performance need to be studied. In order to solve the problem of performance verification for MTRV, a verification device based on echo signal simulation technology is developed in this paper. The measurement mechanism of MTRV with different performance including velocity, distance, and angle is first introduced. Then, a verification method based on the echo signal simulation technology is proposed. The verification device can receive the emission signal of MTRV and process the signal by echo simulation technology, including target generation, Doppler frequency shift, time delay, and angel control, and targets are simulated with nominal velocity, distance, and angle value. The processed echo signal with simulated nominal parameter values is reflected to the MTRV. After the echo signal is received and processed by MTRV, the measurement values of simulated velocity, distance, and angle for targets are obtained. Comparing the measured values of the MTRV with the simulated nominal values of the verification device, the measurement error of MTRV is obtained. The verification device of MTRV is realized to verify the accuracy and reliability of the MTRV measurement results. The simulated velocity range of the verification device is up to (-300~300) km/h, and the simulated distance range of the verification device is up to (10~45) m when the simulated incident angle range was within the range of (-60~60)°. The simulation target generation for the two targets of the device is also verified. And the maximum permissible error (MPE) of the simulated velocity was ±0.05 km/h, the MPE of simulated distance is ±0.3 m, and the MPE of simulated angle is ±0.2°. Finally, the verification and uncertainty evaluation results of the MTRV sample validated the effectiveness and feasibility of the proposed verification method and the developed verification device of MTRV.

The recent success of AlphaFold and RoseTTAFold has demonstrated the values of AI methods in predicting highly accurate protein structures. Despite the advances, their roles in the context of small-molecule drug discovery need to be thoroughly explored. In this study, we evaluated whether the AI-based models can lead to reliable three-dimensional structures of protein-ligand complexes. The structure we predicted was NLRP3, a challenging protein target in terms of obtaining the three-dimensional model both experimentally and computationally. The conformation of the binding pockets generated by the AI models were carefully characterized and compared with experimental structures. Further molecular docking results indicated that AI-predicted protein structures combined with molecular dynamics simulations can be useful in small-molecule drug discovery.

Considering the deep foundation pit of a car dumper room close to the Beijing–Baotou railway, the countermeasures of the foundation pit design are analyzed according to the surrounding environment and stratum conditions. Through Midas GTS software as well as field measured results, the construction effect on the adjacent railway subgrade is discussed. Therefore, the deformation characteristics of the foundation pit as well as the retaining structure, including the railway subgrade, caused by the excavation process, are revealed. The results show that the five-sided water-stop structure formed by cement piles around and at the bottom of the pit avoids the consolidation settlement of the adjacent railway subgrade caused by deep dewatering and also reduces the lateral displacement (i.e., in a horizontal direction) and the heave of the pit bottom. As a result, the lateral displacement near the railway side is larger than that of the retaining structure on the other side due to the subgrade on the pit side. The cross-lot bracing across the foundation pit will transfer the bias pressure of the subgrade to the retaining structure far away from the railway, while the transfer effect of the knee bracing is not obvious. The deformation of the railway subgrade and its evolution rate caused by the removal of internal bracing is significantly greater than the subgrade deformation and the change rate of deformation caused by excavation. The research results provide useful guidance for the deep foundation pit design.

This study investigated kitchen heat exposure and thermal comfort through full-scale experiments and computational fluid dynamics (CFD) simulations. Experiments were conducted in a kitchen-style climate chamber with three stove conditions, three exhaust flowrates of range hood, three external conditions and three makeup air sources. CFD simulations were conducted accordingly to explore more nuances aspects of kitchen thermal environment. The experimental results showed that as the existence of a high-temperature stove, the air temperatures around the cooking staff, the net thermal radiations and local skin temperatures at exposed body parts increased significantly during the cooking period. External conditions and the makeup air source can significantly affect thermal distributions across the kitchen space and the heat exposures around the cooking staff. By adding partitions, using induction cooktops, and turning on the kitchen air conditioner can help to reduce cooking staff’s heat exposure from the gas-burning stove. The CFD simulations were consistent with the measured experimental results. The heat exposure in the cooking zone is shown to be dominated by horizontal thermal asymmetry. The occupants’ thermal comfort in the kitchen can be improved if the makeup air source came from the cooler side with a higher flowrate of range hood.

To address flexural fractures and predict fatigue life, an ordinary state-based peridynamic (PD) fatigue model is proposed for the initiation and propagation of flexural fractures. The key to this model is to replace the traditional partial differential fracture model with a spatially integral peridynamic model. Based on the contact and slip theory, the nonlocal peridynamic contact algorithm is confirmed and the load transfer is through the contact area. With the 3D peridynamic J-integration and the energy-based bond failure criterion, the peridynamic fatigue model for flexural cracks’ initiation and propagation is constructed. The peridynamic solid consists of a pair of gear contact surfaces and the formation and growth of flexural fatigue cracks evolved naturally over many loading cycles. The repeated load is transferred from the drive gear to the follower gear using the nonlocal peridynamic contact algorithm. The improved adaptive dynamic relaxation approach is used to determine the static solution for each load cycle. The fatigue bending crack angle errors are within 2.92% and the cycle number errors are within 10%. According to the experimental results, the proposed peridynamic fatigue model accurately predicts the location of the crack without the need for additional criteria and the fatigue life predicted by the simulation agrees quite well with the experimental results.

The development of seasonal frozen region made the problems of soil pollution more complex. The shear strength characteristics of remolded loess are throughout investigated by direct shear tests with different concentrations of acid and alkali solution and are illustrated by the phenomena of the strength deterioration, which takes the freeze-thaw cycles into consideration. The experiment results show that the freeze-thaw cycle will cause the strength deterioration of soil, although the strength of soil has increased due to the pollution. The different type and adding order of solution will have a different impact on the strength deterioration when soil is under the freeze-thaw cycle. Moreover, the deterioration coefficient of internal friction angle (Kφ) does not change regularly with the increase of the freeze-thaw cycles, and it fluctuates up and down in a small area which does not change a lot. The deterioration coefficient of cohesion (Kc) changes regularly with the increase of the freeze-thaw cycles under all polluted conditions. The type, the adding order, and the concentration of solution all have an effect on the Kc. Strength deterioration model of remolded loess contaminated with acid and alkali solution under freeze-thaw cycles accords with an exponential function.

A novel nitrogen-containing graphitic mesoporous carbon was prepared through MnO-templated method using polyacrylonitrile (PAN) as both carbon and nitrogen sources, and MnCO3 as both template and catalyst precursors. The effects of preparation conditions on the physicochemical properties of obtained samples were systematically investigated. The results showed that as the decrease of the weight ratios of PAN and MnO (2:1–1:4), the increase of carbonization temperature (700–900 °C) and pre-oxidation temperature (180–200 °C), the samples had higher specific surface area, mesopores volume and ratios, up to 507 m2/g, 0.824 cm3/g and 96.83%, respectively. Moreover, the prepared samples presented relatively high graphitic degree and nitrogen contents (~2.21%). The adsorption capacity for acid red 88 (AR88) was as high as 309 mg/g, which were dramatically affected by the mesoporous properties and C- and N-containing groups on the surface of prepared carbon. The rich graphic carbon and pyridine-N in mesoporous carbon generated π-π dispersion and electrostatic interaction with AR88, respectively, which jointly were responsible for the adsorption process. The results of the isotherm and kinetic studies indicated that the AR88 adsorption on mesoporous carbon could be well depicted using Langmuir model and pseudo-2nd-order model.

Creating various fractured micro- and/or nano-structures in sponge-like conductive networks is a promising strategy for fabricating highly sensitive sensors. However, these structural designs will always involve complicated and time-consuming procedures, which severely hinder the application and development of the as-prepared sensors. Herein, an ultrafast and eco-friendly method assisted by microwave (MW) selective heating was proposed to prepare a highly sensitive sensing material, which facilitated the simultaneous reduction of graphene oxide (GO) and formation of a nano-fractured structure. A three-dimensional (3D) conductive network was first constructed by depositing GO and carbon nanotubes (CNTs) on a melamine (ME) sponge. The structural evolution of this coated GO/CNT@ME sponge during MW irradiation was thoroughly investigated. The uniformly distributed CNT served as the MW absorber, and was selectively and rapidly heated upon exposure to MW irradiation. The formed localized “hot spot” (nano-CNT) induced the degradation of the ME skeleton and the in situ reduction of GO, resulting in the construction of a 3D hollow sponge based on micro-fractured backbones covered with nano-voids in just 10 seconds. The final sensor was integrated using this cracked skeleton as the core framework and elastic polydimethylsiloxane (PDMS) as the packaging matrix. Benefitting from this unique multi-level structure, the resultant sensor exhibited an excellent electrical response to mechanical stretching with a wide strain range of 1–50% and a frequency range of 0.05–1 Hz. Besides, these flexible sensors were endowed with good stability and long-term reproducibility over 10 000 cycles. This study also demonstrated the versatile applications of these sensors in distinguishing large- and tiny-scale human motions, including finger bending, pulse beating and vocal vibrations. Thus, this advanced flexible and sensitive sensing material showed great potential in fields of human–machine interaction, health care and wearable devices.

This paper presents a broadband high-efficiency harmonic-tuned power amplifier (PA) with quasi-elliptic low-pass responses. A combination of continuous Class-F-1 and extended continuous Class-F PA modes is employed to significantly expand the design space. A quasi-elliptic low-pass matching network is proposed, which can realize a broadband impedance matching in the predefined optimal impedance region desired by the combination of PA modes. Furthermore, two transmission zeros are generated near the passband, exhibiting high skirt selectivity and providing rapid impedance transition from the passband to the stopband. A wide stopband covering up to the third harmonic is achieved which shows good harmonic suppression. Design procedures of the proposed broadband PA are presented. To verify the proposed methodology, the broadband PA is fabricated and measured. The implemented PA achieves a bandwidth of 145.2% from 0.5 to 3.15 GHz. Over this frequency range, the drain efficiency is measured as 58-74.9% with the output power of greater than 39.03 dBm and a large signal gain ranging from 8.43 to 15.67 dB. A wide stopband is realized from 3.4 to 10 GHz, showing excellent quasi-elliptic low-pass responses. The measured adjacent leakage ratios (ACLRs) using a 20-MHz LTE signal with digital pre-distortion are below -45.06 dBc.

Global climate change, temperature rise and some kinds of extreme meteorological disaster, such as the drought, threaten the development of the natural ecosystem and human society. Forecasting in drought is an important step toward developing a disaster mitigation system. In this study, we utilized the statistical, autoregressive integrated moving average (ARIMA) model to predict drought conditions based on the standardized precipitation index (SPI) and standardized precipitation evapotranspiration index (SPEI) in a major tributary in the lower reaches of Nu River. We employed data from 2001 to 2010 to fit the model and data from 2011 to 2013 for model validation. The results showed that the coefficients of determination (R2) was over 0.85 in each index series, and the root-mean-square error and mean absolute error were low, implying that the ARIMA model is effective and adequate for this region.

In this work, the properties of a two-tone signal driven concurrent power amplifier (CPA) are analyzed extensively. Firstly, the characteristics of two-tone signals are discussed to explain the nonlinearity and efficiency of two-tone signal driven CPA. Secondly, a method of how to solve the efficiency of a two-tone signal driven CPA is proposed in this paper with a detailed calculation procedure and complete theory. Finally, a general empirical expression to calculate the drain efficiency (DE) of CPA versus the frequency ratio and the amplitude ratio of the two carriers is proposed. Simulation results and experimental verifications are given to validate the proposed analytical formulation to predict the efficiency of CPAs when driven with balanced or imbalanced two-tone signals.

In this article, a novel nested-mode power amplifier (NMPA) is proposed for highly efficient multi-octave applications. By introducing a group of nested guaranteed regions (GRs) at the fundamental and harmonic frequencies as the target design space, the difficulties caused by frequency overlapping in harmonically tuned multi-octave power amplifiers (PAs) can be overcome, leading to a self-consistent theory of multi-octave PAs. Furthermore, the methodology of constructing the proposed nested GRs is demonstrated based on a simplified numerical model. According to the methodology, the desired nested GRs can be constructed by following several well-defined closed-form steps. In addition, a feasible design methodology of the NMPA is established based on a simplified deembedding technique of packaged devices. Based on the proposed theory and design method, a 1–3100-MHz NMPA is designed and measured. According to the measured results, the designed PA exhibits 57.5–73.9% drain efficiency and 39–42.6-dBm output power across the band. Moreover, the linearity and linearizability of the designed NMPA are verified using up to 20-MHz-bandwidth-modulated signals across the designed band accompanied with a digital predistortion (DPD) procedure. To the best of our knowledge, this is the state-of-the-art performance of multi-octave broadband PAs.

In this article, a modified beam-oriented digital predistortion (BO-DPD) utilizing the over-the-air diversity feedbacks (OTA DFBs) is proposed for linearizing the hybrid beamforming (HBF) large-scale array. The proposed DPD can solve the hardware implementation issue of conventional DPD architecture in HBF array by estimating and linearizing the main beam signal while avoiding the complex feedback configurations. Different from the far-field OTA measurements, the OTA feedback receivers are placed symmetrically inside the transmit array according to its geometric structure. Theoretical analysis proves that it is possible to derive the main beam signal from the OTA feedback information directly by adjusting the phase shifter of each branch using a relative simple procedure which allows the predistorter to be identified based on the estimated main beam signal. Furthermore, an iterative algorithm for eliminating uncorrelated coupling interference from other subarrays in the feedback signal is proposed. Measurement results on a $1 \times 4$ transmitter and a $2 \times 3$ transmitter as well as simulations on a $4 \times 64$ array are presented to benchmark the proposed DPD technique against the existing techniques. Better than 15-dB adjacent channel power ratio (ACPR) improvement has been realized with the proposed DPD.

A novel highly linear magnetless isolator based on weakly coupled nonreciprocal metamaterials is proposed in this article. Nonreciprocal devices, such as isolators and circulators, are widely used in modern microwave, optics. Nowadays, nonreciprocity is exclusively achieved with anisotropic magneto-optic material. Unfortunately, this material needs permanent magnetic bias and is typically bulky, which remains incompatible with technology for integrated circuit. In this article, we reveal that strong isolation can be achieved even under the weak coupling between the transmission line and magnetless nonreciprocal metamaterials (MNMs). Compared with previous magnetless nonreciprocal approaches, in this article, as the wave propagates from port 2 to port 1, the interaction between the incoming wave and nonlinear devices can be neglected due to the weak coupling, yielding low loss (|S12| = −1.03dB) and high linearity $({P}_{{1dB}}{>{17} {dBm}}$ , ${{OIP}}_{{3}}{=33.5 {dBm})}$ . As the wave propagates from port 2 to port 1, 36.2 – dB isolation can be achieved under the loop resonance. Furthermore, the frequency reconfiguration of MNMs has been investigated for the first time, leading to broadband and multiband isolators.

Sharp corners usually are used on glass contours to meet the highly increasing demand for personalized products, but they result in a broken wheel center toolpath in edge grinding. To ensure that the whole wheel center toolpath is of G1 continuity and that the grinding depth is controllable at the corners, a transition toolpath generation method based on a velocity-blending algorithm is proposed. Taking the grinding depth into consideration, the sharp-corner grinding process is planned, and a velocity-blending algorithm is introduced. With the constraints, such as traverse displacement and grinding depth, the sharp-corner transition toolpath is generated with a three-phase motion arrangement and with confirmations of the acceleration/deceleration positions. A piece of glass with three sharp corners is ground on a three-axis numerical-control glass grinding equipment. The experimental results demonstrate that the proposed algorithm can protect the sharp corners from breakage efficiently and achieve satisfactory shape accuracy. This research proposed a toolpath generation method based on a velocity-blending algorithm for the manufacturing of personalized glass products, which generates the transition toolpath as needed around a sharp corner in real time.

Directional modulation (DM) implemented at the transmitter side is a physical layer security technology based on the multi-antenna structure. Current DM methods paid little attention to the issue of the nonlinear distortion of power amplifiers (PAs), which may lead to poor amplifier efficiency and worsen the signal’s error vector magnitude (EVM). For the first time, we consider linearization of a DM transmitter using the digital predistortion (DPD) technique. We modify the paralleled DM DPD model to a novel cascaded model based on the characteristics of the DM transmitter. This modified method applies a common DPD to mitigate the nonlinear distortion of all paths and an auxiliary DPD to fine-tune each path, so as to significantly reduce the complexity. In order to validate this idea, two-element uniform linear array (ULA) and four-element ULA experiments were performed, in which 16QAM 20-MHz bandwidth signals with a peak-to-average power ratio (PAPR) of about 8.0 dB were generated for commercial part PAs. Experimental results show that the modified approach has almost the same linearization performance as the paralleled DM DPD technique but reduces the computational complexity significantly.

The multifunctional epoxy (EP) composites based on three-dimensional interconnected graphene and carbon nanotubes (CNT) were prepared, in which this carbon network was designed by depositing reduce...

IntroductionThis study investigated the relationships between differentially co-expressed gene pairs or links (DCLs) and transcription factors (TFs) in the gene transcription regulatory network (GTRN) to clarify the molecular mechanisms underlying the pathogenesis of Parkinson’s disease (PD).Material and methodsMicroarray dataset GSE7621 from Gene Expression Omnibus (GEO) was used to identify differentially expressed genes (DEGs) and perform Gene Ontology (GO) enrichment analysis. Differentially co-expressed genes (DCGs) and DCLs were identified by the DCGL package in R soft-ware. DCLs that were potentially related to the regulation mechanisms, and corresponding TFs, were identified using the DR sort function in the DCGL V2.0 package. The GTRN was constructed with these DCLs-TFs, and visualized with Cytoscape software.ResultsA total of 131 DEGs, including 77 up-regulated DEGs and 54 down-regulated DEGs, were identified, which were mainly enriched for plasma membrane, cell activities, and metabolism. We found that ICAM1-LTBP and CTHRC1-UTP3 might alter gene regulation relationships in PD. The GTRN was constructed with DCLs-TFs, including 348 nodes (118 TFs and 230 DCGs) and 1045 DCLs. These TFs (AHR, SP1, PAX5, etc.) could regulate many target genes (e.g. ICAM1 and LTBP) in the GTRN of PD.ConclusionsICAM1 and LTBP may play a role in PD symptom development and pathology, and might be regulated by important TFs (AHR, SP1, PAX5, etc.) identified in the GTRN of PD. These findings may help elucidate the molecular mechanisms underlying PD and find a novel drug target for this disease.

The aim of this study was to assess factors associated with conservative management failure in patients with symptomatic isolated mesenteric artery dissection.Patients with symptomatic isolated mesenteric artery dissection who underwent conservative therapy as first line treatment between February 2010 and May 2018 were included in this retrospective study. Conservative management failure was defined as the persistence or aggravation of symptoms and signs, increasing aneurysmal dilation, or new appearance of a dissecting aneurysm after conservative management. Univariable and multivariable analyses were performed to identify risk factors for failure of conservative management.A total of 123 patients (115 men, 8 women, mean age, 53.7 ± 6.1 years) were included in this study. Conservative management was successful in 89 (72.4%) patients but failed in the remaining 34 (27.6%) patients. Of the 89 for whom conservative management was successful, all of the symptoms were eliminated (n = 81) or relieved (n = 8) within 3.8 ± 0.7 days after conservative management. All of the 34 patients in whom conservative management failed underwent successful endovascular stenting. Failure of conservative management was associated with type II IMADs as defined by the Sakamoto classification (meaning that there is an entry tear, but no re-entry, and still no thrombosis of false lumen, odds ratio: 33.76; 95% confidence interval 8.65-131.85; p .001) and with ≥90% luminal stenosis (odds ratio 40.70; 95% confidence interval: 3.76-440.07; p .01).Conservative management can be used successfully in most patients with symptomatic isolated mesenteric artery dissection. Risk factors for failed conservative treatment were type II IMADs and degree of luminal stenosis ≥90%.

Objective: To compare the efficacy of kinesio taping on chronic non-specific low back pain with that of other general physical therapies. Methods: Relevant studies published up to 31 July 2018 were searched in electronic databases (PubMed, Web of Science, Science Direct, Physiotherapy Evidence Database (PEDro), Cochrane Library, Wanfang Data, Vip Data and China National Knowledge Infrastructure). The quality of included studies was assessed using a risk of bias assessment tool, as recommended by the Cochrane Collaboration. Data from visual analogue scales and Oswestry Disability Index were extracted as selected outcome indicators. Tests of heterogeneity were performed. Weight-ed mean difference (WMD) data with its 95% confidence intervals (95% CI) were used as a measure of effect sizes, in order to pool the results from each included study using either a fixed or random effects model (where appropriate and possible). Results: Eight studies fulfilled the inclusion and exclusion criteria. The quality of included studies was moderate. Patients with chronic non-specific low back pain in the kinesio taping group achieved better pain relief (WMD = –1.22; 95% CI –1.49 to –0.96, I2 = 91%, p

The vibration propagates through the shaft in the form of elastic waves. The propagation characteristics of the elastic waves are affected by the axial loads. The influence of the axial loads to the propagation characteristics of the elastic waves is studied in this paper. Firstly, the transfer matrix of the elastic waves for the non-uniform shaft with axial loads is deduced by combining the transfer matrix without axial load and the additional equation caused by the axial load. And then, a numerical method is used to study the influence of the axial load, non-uniformity and the rotating speed to the propagation characteristics of the elastic waves. It’s found that a new Stop Band will appear due to the axial force, and the central frequency of which will decrease as the increase of the force, while the band width of which remains the same. The central frequency of the new Stop Band will also increase as the increase of the cross-section area ratio; however, the rotating speed of the shaft doesn’t affect the propagation characteristics of the elastic waves obviously. Finally, an experimental rig is built up for further study, even though there are some small local errors, the results of experiments match well with the numerical ones, which indicates the validation of the theoretical results. The result can help to study the influence of the axial load to the dynamics of a non-uniform shaft and help to reveal the vibration propagating mechanism in such a shaft.

In this paper, a Ka/Q dual-band Doherty power amplifier (DPA) with simplified offset lines is implemented in a 0.1- $\mu \text{m}$ gallium arsenide (GaAs) process. It is found that the dual-band transmission lines (TLs) employed in the sub-6-GHz dual-band DPA are not suitable to be used as the offset lines in millimeter-wave (mm-wave) dual-band DPAs due to their large sizes and insert losses. An in-depth analysis reveals that the phase requirement of the offset lines can be relaxed, and the DPA exhibits a reasonable performance in a certain phase-shift range. A novel design method is proposed to realize offset lines using simple TLs, which can satisfy the phase-shift ranges in dual bands by choosing a proper electrical length. To enhance the gain of the DPA, a reversed uneven power splitter is adopted to deliver more power to the main power amplifier (PA). The fabricated DPA achieves an output power of 25.4/25.2 dBm, a peak power-added efficiency (PAE) of 33%/25%, and a 6-dB back-off PAE of 22%/17% at 29/46 GHz, respectively, with a compact size of 2.2 1.4 mm2. Applying a 20-MHZ 64-quadratic-amplitude modulation (QAM) signal with a 7.7-dB peak-to-average power ratio (PAPR), the measured average output power, PAE, and error vector magnitude (EVM) at 29/46 GHz are 18.4/19 dBm, 17%/15%, and 1.5%/1.1% after linearization, respectively. To the best of our knowledge, the proposed DPA is the first demonstration of mm-wave dual-band DPAs that do not require any additional switching or reconfiguration.

This paper is a literature review of field studies on fan-use rates and their effects on thermal comfort, energy conservation, and human productivity. In the assessed literature, fans are more popular in Asia, and more used in mixed-mode (MM) and naturally ventilated (NV) buildings than in air-conditioned (AC) buildings. On the basis of collected fan-use models, probit regression models of fan-use rates and ambient environments were obtained and indicate that the essential trigger of fan-use is a warm environment rather than building types. This result helps us to understand the control behaviors and comfort requirements of occupants. Also, fans could provide benefits in three aspects: widening neutral temperatures, saving energy, and improving occupants’ productivity. First, using fans in buildings elevates the neutral temperature and the upper limit of neutral zone (0.5 thermal sensation scale) averages by about 3 K in ranges from 25.7 °C to 28.7 °C and 27.5 °C to 30.7 °C, respectively. Second, fan-use reduces AC-use rates in MM buildings in summer. The regression models based on the collected AC-use rate models illustrate that, on average, AC-use is expected to be reduced by about 15% in summer when fans are used. Third, providing occupants access to fans could improve occupants’ productivity. Based on the limited data available, a 3-K temperature extension is achieved by fans ensuring productivity not decreasing. This review could shed some light on the extension of the neutral temperature range, predictions of MM buildings’ energy consumptions, and methods to enhance productivity. Additionally, this review suggests some valuable directions for future research on fans.

We measured indoor air speeds generated by ceiling fans in 78 full-scale laboratory tests. The factors were the room size, fan diameter, type, speed, direction (up or down), blade height, and mount distance (i.e. blade to ceiling height). We demonstrated the influence of these factors, showing that the most significant are speed, diameter and direction. With other factors fixed, the average room air speed in the occupied zone increases proportionally with fan air speed and diameter. Blowing fans upwards yields lower but far more uniform air speeds than downwards. We show that for the same fan diameter and airflow, fan type has little effect on the air speed distribution in the region outside the fan blades. We developed several new dimensionless representations and demonstrate that they are appropriate for comparisons over a wide range of fan and room characteristics. Dimensionless linear models predict the lowest, average, and highest air speeds in a room with a median (and 90th percentile) absolute error of 0.03 (0.08), 0.05 (0.13), and 0.12 (0.26) m/s respectively over all 56 downwards tests, representing common applications. These models allow designers to quickly and easily estimate the air speeds they can expect for a given fan and room. We include all measured data and analysis code in this paper.

The propagation mechanism of vibration in a media such as a non-uniform rotating shaft is an important topic since it can help to control the vibration of the media, or to reduce the noise. Vibration propagates in a non-uniform rotating shaft in the form of elastic waves and the propagation characteristics of the waves are affected by the non-uniform factors, the transverse cracks and the rotating speed, etc. This study deals with the propagation characteristics of the elastic waves in a non-uniform shaft with transverse cracks by adopting the Transfer Matrix method. First, the transfer matrix for a single non-uniform shaft is derived by constructing the motion equations derived with Equilibrium Equations. Second, the transfer matrix for a transverse crack is studied. Crack Mode III is adopted, and the transverse crack is modeled as a local spring, the local flexibility coefficient of which is deduced. The transfer matrix for the non-uniform shaft with transverse cracks is then derived by combining the individual matrixes. Finally, several numerical examples are used to illustrate the influence of different crack depths and alternative rotating speeds on the propagation characteristics of the elastic waves, which are compared with the results from the experimental analyses. It's shown that a new stop band will come out at lower frequency region when a transverse crack occurs and the bandwidth of which will be wider and wider as the increase of the depth of the crack, and the rotating speed mainly affects the first stop band, the central frequency of which will decrease as the increase of the rotating speed.

Objective The aim was to evaluate the outcomes of endovascular treatment with bare stents alone versus stent assisted coiling in isolated mesenteric artery dissection (IMAD) aneurysms. Methods Patients with an IMAD aneurysm who underwent endovascular stenting between February 2010 and February 2017 at one of three institutions were included in this study. Data regarding technical success, procedure time, symptom resolution, complications, changes in IMAD aneurysm, and stent patency were recorded. Results A total of 38 patients (35 men) were included, 27 treated with bare stents alone and 11 treated with stent assisted coiling. Technical success was achieved in 100% of patients treated with bare stents and in 81.8% of those treated with stent assisted coiling (p = 0.078). The mean procedure times were 62.6 ± 5.3 min for treatment with bare stents and 116.4 ± 8.4 min for stent assisted coiling (p Conclusions Bare stents alone and stent assisted coiling have high technical success rates and demonstrate good intermediate patency in patients with an IMAD aneurysm. Bare stents alone may serve as an alternative to stent assisted coiling for the management of IMAD aneurysm

This paper presents a broadband three-stage Doherty power amplifier (DPA) using impedance compensation for bandwidth extension. Different from the conventional design, an impedance-compensating load combiner is proposed to broaden the bandwidth of the three-stage DPA by employing the output impedances of the peaking amplifiers. Considering the load impedance of the peaking branch as an independent design variable, the Doherty load modulations are analyzed in theory, pointing out the optimized solution for the load combiner. To achieve the impedance compensation, the peaking output matching networks are deliberately designed with the dual-impedance matching topology. Experimental results show that a three-stage DPA is realized from 1.6 to 2.6 GHz (48% fractional bandwidth) with a measured efficiency of 50%–53% at 9.5-dB back-off and a saturated output power around 45.5 dBm. When stimulated by the 20- and 40-MHz modulated signals at an average output power of around 36.5 dBm, the proposed DPA can achieve the adjacent channel leakage ratio of −50 dBc over the whole frequency band after linearization, with an average efficiency of higher than 50%.