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Aims: General anesthesia has been used in surgical procedures for approximately 180 years, yet the precise mechanism of anesthetic drugs remains elusive. There is significant anatomical connectivity between the ventral tegmental area (VTA) and the prelimbic cortex (PrL). Projections from VTA dopaminergic neurons (VTADA) to the PrL play a role in the transition from sevoflurane anesthesia to arousal. It is still uncertain whether the prelimbic cortex pyramidal neuron (PrLPyr) and its projections to VTA (PrLPyr‐VTA) are involved in anesthesia‐arousal regulation. Methods: We employed chemogenetics and optogenetics to selectively manipulate neuronal activity in the PrLPyr‐VTA pathway. Electroencephalography spectra and burst‐suppression ratios (BSR) were used to assess the depth of anesthesia. Furthermore, the loss or recovery of the righting reflex was monitored to indicate the induction or emergence time of general anesthesia. To elucidate the receptor mechanisms in the PrLPyr‐VTA projection's impact on anesthesia and arousal, we microinjected NMDA receptor antagonists (MK‐801) or AMPA receptor antagonists (NBQX) into the VTA. Results: Our findings show that chemogenetic or optogenetic activation of PrLPyr neurons prolonged anesthesia induction and promoted emergence. Additionally, chemogenetic activation of the PrLPyr‐VTA neural pathway delayed anesthesia induction and promoted anesthesia emergence. Likewise, optogenetic activation of the PrLPyr‐VTA projections extended the induction time and facilitated emergence from sevoflurane anesthesia. Moreover, antagonizing NMDA receptors in the VTA attenuates the delayed anesthesia induction and promotes emergence caused by activating the PrLPyr‐VTA projections. Conclusion: This study demonstrates that PrLPyr neurons and their projections to the VTA are involved in facilitating emergence from sevoflurane anesthesia, with the PrLPyr‐VTA pathway exerting its effects through the activation of NMDA receptors within the VTA. [ABSTRACT FROM AUTHOR]

Background: Breast fibroadenoma poses a significant health concern, particularly for young women. Computer-aided diagnosis has emerged as an effective and efficient method for the early and accurate detection of various solid tumors. Automatic segmentation of the breast fibroadenoma is important and potentially reduces unnecessary biopsies, but challenging due to the low image quality and presence of various artifacts in sonography. Methods: Human learning involves modularizing complete information and then integrating it through dense contextual connections in an intuitive and efficient way. Here, a human learning paradigm was introduced to guide the neural network by using two consecutive phases: the feature fragmentation stage and the information aggregation stage. To optimize this paradigm, three fragmentation attention mechanisms and information aggregation mechanisms were adapted according to the characteristics of sonography. The evaluation was conducted using a local dataset comprising 600 breast ultrasound images from 30 patients at Suining Central Hospital in China. Additionally, a public dataset consisting of 246 breast ultrasound images from Dataset_BUSI and DatasetB was used to further validate the robustness of the proposed network. Segmentation performance and inference speed were assessed by Dice similarity coefficient (DSC), Hausdorff distance (HD), and training time and then compared with those of the baseline model (TransUNet) and other state-of-the-art methods. Results: Most models guided by the human learning paradigm demonstrated improved segmentation on the local dataset with the best one (incorporating C3ECA and LogSparse Attention modules) outperforming the baseline model by 0.76% in DSC and 3.14 mm in HD and reducing the training time by 31.25%. Its robustness and efficiency on the public dataset are also confirmed, surpassing TransUNet by 0.42% in DSC and 5.13 mm in HD. Conclusions: Our proposed human learning paradigm has demonstrated the superiority and efficiency of ultrasound breast fibroadenoma segmentation across both public and local datasets. This intuitive and efficient learning paradigm as the core of neural networks holds immense potential in medical image processing. [ABSTRACT FROM AUTHOR]

Straw biorefinery offers economical and sustainable production of chemicals. The merits of cell immobilization technology have become the key technology to meet d-lactic acid production from non- detoxified corn stover. In this paper, Low acyl gellan gum (LA-GAGR) was employed first time for Lactobacillus bulgaricus T15 immobilization and applied in d-lactic acid (D-LA) production from non-detoxified corn stover hydrolysate. Compared with the conventional calcium alginate (E404), LA-GAGR has a hencky stress of 82.09 kPa and excellent tolerance to 5-hydroxymethylfurfural (5-HMF), ferulic acid (FA), and vanillin. These features make LA-GAGR immobilized T15 work for 50 days via cell-recycle fermentation with D-LA yield of 2.77 ± 0.27 g/L h, while E404 immobilized T15 can only work for 30 days. The production of D-LA from non-detoxified corn stover hydrolysate with LA-GAGR immobilized T15 was also higher than that of free T15 fermentation and E404 immobilized T15 fermentation. In conclusion, LA-GAGR is an excellent cell immobilization material with great potential for industrial application in straw biorefinery industry. [ABSTRACT FROM AUTHOR]

In this study, nano‐alumina/graphene oxide (GO‐Al2O3) nanohybrids were synthesized and incorporated into a ceramic matrix to enhance the anticorrosion performance of chemically bonded ceramic coatings. The interaction between GO and nano‐Al2O3 was investigated using Fourier transform infrared spectroscopy, Raman spectroscopy, and scanning electron microscopy. Results showed that nano‐Al2O3 was successfully decorated on the surface of GO through chemical bonds, which improved the bonding strength between GO and the ceramic matrix through the reaction of the aluminum phosphate binder with nano‐Al2O3. The unique structures of the GO‐Al2O3 nanohybrids endowed the ceramic coatings with superior anticorrosion properties as compared to the untreated substrate and pure ceramic coatings. The best corrosion resistance of coatings was achieved when the content of the GO‐Al2O3 nanohybrids was 0.6 wt%, which led to the highest protection efficiency (93.4%) and the smallest corrosion current (icorr). The improvement in the corrosion resistance of the ceramic coatings was attributed to the excellent compatibility and dispersibility of the GO‐Al2O3 nanohybrids in the ceramic matrix. In addition, the greater bonding strength between the GO‐Al2O3 nanohybrids and ceramic matrix could enable more fracture energy to be consumed. This in turn could block or change the diffusion pathway of cracks, resulting in higher corrosion resistance. [ABSTRACT FROM AUTHOR]

In our previous study, human fibroblast growth factor 1 was successfully fused with oleosomes, energy-storing organelles of seeds, which are considered to be excellent "expression carriers" for substances with a convenient purification process. The present work aimed to explore the beneficial effects of oleosomes fused with human fibroblast growth factor 1 (OLAF) on wound healing. The data showed marked improvements in terms of the angiogenesis, vascular integrity, collagen and inflammation on the wound sites of rats with a full-thickness skin defect. Moreover, the positive role of OLAF in promoting angiogenesis and its possible pathways were clarified in vivo and in vitro. The results showed that the number, length and branches of the blood vessels of the chick embryo chorioallantoic membrane were markedly increased after OLAF treatment. Meanwhile, the in vitro results also revealed that 100 ng/mL OLAF exhibited a promoting effect on the proliferation, migration and tube formation of human umbilical vein endothelial cells. In addition, the potential of OLAF to improve wound angiogenesis was demonstrated to be associated with an up-regulated PI3K/Akt pathway by transcriptome sequencing analysis and the introduction of a PI3K/Akt pathway inhibitor (LY294002). These findings suggest that OLAF has many prospects in the development of drugs for wound healing. [ABSTRACT FROM AUTHOR]

The presence of near-surface karst voids is an extremely difficult issue in the construction of a high-speed rail (HSR) foundation. Seismic constant-offset profile (COP) method is one of the shallow geophysics technologies which may be used for the detection of karst voids. Although a COP image does not directly reveal the characters related to the anomalies in a karst terrain, the dominant frequency of the COP image in a karst terrain is significantly lower than the dominant frequency over the background without karstification or voids. This dominant-frequency anomaly is due to the strong attenuation effect when seismic waves propagate through any karst voids. Thus, we propose using the dominant-frequency anomalies of the COP image to directly detect near-surface karst voids in a karst terrain. First, we generate a high-resolution time–frequency spectrum for each COP trace, using the modified Wigner-Ville distribution (WVD) algorithm which combines WVD with a multichannel maximum entropy method. Second, we estimate a high-precision dominant-frequency function which varies along the reflection time, based on the corresponding high-resolution time–frequency spectrum. Finally, we detect the geological anomalies by analyzing low-frequency distributions in the dominant-frequency image for all traces. We demonstrate this procedure with a case study for the detection of karst voids within the high-speed rail foundation in a karst terrain, and verify the interpretation of hidden voids, cavities, clays and peats directly with drilling cores. [ABSTRACT FROM AUTHOR]

Wearable health monitoring sensors, when employed to monitor pulse and sweat volume in real‐time during human physical activity, serve as an effective preventative measure against abnormal health conditions, such as elevated heart rate or excessive dehydration. Herein, a dual‐functional sensor based on a sandwich structure composed of polyvinylidene fluoride hexafluoropropylene / conductive carbon black perforated film (named PCp film) and corncob sponge is designed to monitor pulse and sweat volume. The PCp film prepared by the breath figure method serves as a piezoresistive sensor with high sensitivity (0.06 kPa−1), a fast response time (0.9 ms), and high reusability for pulse monitoring. Furthermore, the PCp film has excellent water permeability (27.3 L m−2 h−1); thus, the sweat permeating through the PCp film can be absorbed by the corncob sponge. The sandwich‐structured capacitive sensor is also highly sensitive (6.021 pF nL−1) to the absorbed sweat and is highly reusable. In addition, the dual‐functional sensor is successfully integrated into a sports bracelet system to display real‐time pulse and sweat‐volume data of the wearer. This approach provides a dependable foundation for the advancement of multifunctional sensors in the field of sports monitoring. [ABSTRACT FROM AUTHOR]

Background: The neuropeptide orexin promotes arousal from general anaesthesia, however the neuronal circuits that mediate this effect have not been defined. We investigated whether orexinergic neurones modulate the basal forebrain (BF) and locus coeruleus (LC) in emergence from anaesthesia.Methods: Hcrtcre rats were generated using a CRISPR/Cas9-based approach. Viruses encoding optogenetic probes were injected into the perifornical lateral hypothalamic (PeFLH) area, optogenetic fibres were embedded in the PeFLH, BF, or LC, and changes in anaesthesia state under 1.4 vol% or 0.8 vol% isoflurane were determined.Results: In the PeFLH, 98.8% (0.4%) of orexin-A-positive cells expressed tdTomato, and 91.9% (2.2%) of tdTomato cells were orexin-A-positive. Under 1.4 vol% isoflurane anaesthesia, compared with control groups, burst suppression ratio was less, and emergence time was shorter in groups with optogenetic activation of orexinergic cell bodies in the PeFLH (923 [162] vs 493 [68] s, P=0.0003) or orexinergic terminals in the BF (937 (122) vs 674 (108) s, P=0.0049) or LC (913 [128] vs 742 [76] s, P=0.022). Optical stimulation of orexinergic terminals in the BF and LC also improved the movement scores of rats under 0.8 vol% isoflurane anaesthesia.Conclusions: Activation of orexinergic terminals in the FB or LC mediates facilitation of emergence from anaesthesia by orexinergic neurones during isoflurane anaesthesia. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) decorated multi-walled carbon nanotubes (MWCNTs) hybrid material was prepared to improve the tribological performance of chemically bonded ceramic coatings. TEM results reveal that ZnO has been successfully fabricated on the surface of MWCNTs. The tribological performance of the ceramic coatings with MWCNTs–ZnO hybrid material was investigated using a ball-on-disc method. The results show that the friction coefficient and wear rate of the ceramic coatings decrease with the increase of MWCNTs–ZnO hybrid material. The ceramic coatings with MWCNTs-ZnO hybrid material shows a smooth worn surface with less cracks and delamination. In addition, the worn surface of the counterpart ball shows a smaller worn area and a smooth surface. The excellent wear resistance of the ceramic coatings is attributed to the good bonding strength between MWCNTs–ZnO hybrid material and ceramic matrix. [ABSTRACT FROM AUTHOR]

The following conclusions can be drawn: Under partially submerged flow conditions, the prediction accuracies of both Wingate software and the identification method suggested by the original paper were the best, followed by the empirical relationship method by Wu (2008) and the dimensionless method by Bijankhan et al. (2013), in that order. The identification method proposed by the original paper significantly improved the discharge prediction accuracies and the maximum error was only 23%, wherein the constant parameters were re-calibrated by the least squares fitting (Guo et al., [6]). Discharge calibration for gates is certainly a research area that merits a great deal of attention in order to improve discharge measurement and automatic control. [Extracted from the article]

Graphene oxide (GO) decorated by titanium dioxide (TiO2) was fabricated and introduced into the chemically bonded ceramic coatings as a nanofiller. The analysis of the results of thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electronic microscopy (SEM), and transmission electron microscopy (TEM) show that TiO2 has decorated on the surface of GO by chemical bonds. Furthermore, the effect of incorporating GO-TiO2 on properties of ceramic coatings was investigated. The results show that GO-TiO2 achieved a homogeneous dispersion and compatibility in ceramic matrix without obvious cracks. The potentiodynamic polarization test was conducted to investigate the influence of GO-TiO2 on the corrosion behavior. The results demonstrated that corrosion resistance of ceramic coatings remarkably enhanced by adding GO-TiO2. Furthermore, the anticorrosive mechanisms of ceramic coatings with GO-TiO2 were tentatively discussed. [ABSTRACT FROM AUTHOR]

Tanshinone IIA (TSA), a principal component derived from the Traditional Chinese Medicine Danshen has been suggested to exert neuroprotective effect against experimental cerebral ischemic/reperfusion injury. But the associated underlying mechanisms still have not been understood. The current study characterized the role of nuclear factor erythroid two-related factor-induced antioxidant response in the neuroprotective efficacy of TSA treatment. The focal cerebral ischemia/reperfusion model was established by 60-minute middle cerebral artery occlusion. At the onset during reperfusion, mice were treated with 10 mg/kg TSA intraperitoneally. The mRNA and nuclear factor erythroid 2 (Nrf2) protein expression, the antioxidant enzymes, and oxidative production levels were measured. To further verify the role of Nrf2 in the neuroprotective effect induced by TSA, the Nrf2 small silenced RNA and Nrf2 knockout mice were used, the neurological function, brain infarct volume, and cellular apoptosis examination were assessed. TSA treatment improved neurological scores, reduced infarct volume, and attenuated the cellular apoptosis. TSA treatment upregulated the expression of Nrf2 mRNA and the contents of Nrf2 protein in nuclear extract. Nrf2 activation by TSA treatment increased the contents of antioxidant enzymes, and reduced the generation of oxidative productions. Either Nrf2 knockdown or Nrf2 knockout abolished the antioxidative and neuroprotective effect of TSA treatment. These results demonstrate that the Nrf2 activation contributes to TSA-induced neuroprotection from experimental ischemic stroke through maintaining antioxidant effect. [ABSTRACT FROM AUTHOR]

With thermal chemical reaction, the chemically bonded ceramic coatings are prepared on A3 steel. Influence of zinc oxide on corrosion resistance of the coating is investigated by corrosion polarization analysis. It is found that the chemically bonded ceramic coatings show the outstanding corrosion resistance. In addition, the coating with zinc oxide possesses a smaller reaction rate and corrosion current density than the coating without zinc oxide. Scanning electron microscope (SEM) analysis and X-ray diffraction (XRD) analysis are conducted to find the reason. Without adding zinc oxide, AlPO is the main binding phase connecting with the particles in the coating, and the micro structure of the particles can be seen clearly. However, with adding zinc oxide, a new binding phase Zn3(PO) is found in the coating. Besides, the particles in the coating are fully covered with Zn(PO) and AlPO, and the micro structure of the particles cannot be clearly seen. The particles have a better cover with the binding phase compared with the particles without zinc oxide. Therefore, adding zinc oxide makes the coating more compact that hinders access of HO, O, and Cl to the substrate with the compact coatings, which improves the corrosion resistance of the chemically bonded ceramic coatings. [ABSTRACT FROM AUTHOR]

This paper analyzes the influence of the Miller effect on the gain performance of the cascode stage. A passive compensation network is proposed to cancel Cbc at the millimeter-wave range without distinct penalty on noise figure and stability. Using this passive compensation network, the cascode stage can achieve a higher gain in a wider bandwidth than other cascode topologies. Furthermore, a W-band amplifier based on the new cascode stage is designed and fabricated using the 0.13-\mum BiCMOS process successfully. The proposed passive compensation network has a potential to be used in other building blocks, which need improvement through Miller effect cancellation. [ABSTRACT FROM PUBLISHER]

In recent years, transition-metal silicon-based high temperature materials have attracted more and more attention due to their excellent physical and chemical properties. In this paper, we explored the phase stability, mechanical, anisotropy and thermodynamic properties of TM 5 Si 4 (TM = Sc, Y, Ti, Zr and Hf) compounds by first-principles calculations. The results indicate that TM 5 Si 4 compounds exhibit the thermodynamical and dynamical stability. And Hf 5 Si 4 exhibits the best phase stability among five compounds. The orthorhombic Sc 5 Si 4 and Y 5 Si 4 are ductile, but the tetragonal Ti 5 Si 4 , Zr 5 Si 4 and Hf 5 Si 4 are brittle. The elastic anisotropies of TM 5 Si 4 were demonstrated by the 3D contours and 2D projections of elastic modulus. The results confirm that the order of anisotropy is as follows: Zr 5 Si 4 < Hf 5 Si 4 < Ti 5 Si 4 < Sc 5 Si 4 < Y 5 Si 4. TM-Si bonds can be formed in TM 5 Si 4 silicides for the strong localized hybridization between TM-d and Si-3p states. Moreover, the thermal parameters confirm that five TM 5 Si 4 silicides display the better thermal stability at elevated temperature. • The mechanical, and thermodynamic properties of TM 5 Si 4 compounds were explored. • The results showed that the TM 5 Si 4 compounds exhibit the phase stability. • The orthorhombic Sc 5 Si 4 and Y 5 Si 4 s exhibit ductile behavior. • The elastic anisotropies of TM 5 Si 4 were intuitively demonstrated. [ABSTRACT FROM AUTHOR]

In present work, the effects of vacancy defects on the mechanical and thermodynamic properties of Cr 5 Si 3 have been investigated using the first-principles. The occupation mechanism of oxygen atoms in Cr 5 Si 3 is also carefully analyzed and discussed. The vacancy formation, lattice vibrations, electronic structure, elasticity and thermodynamic parameters of Cr 5 Si 3 were calculated separately. The results show that Cr 5 Si 3 is stable and irrespective of the presence of vacancies or oxygen atoms occupation in it. In addition, the Si vacancies cause Cr 5 Si 3 to undergo a brittle to ductile transition, which originates the weak hybridization between Cr and Si atoms. Importantly, when the Si -Va2 vacancy is occupied by oxygen atom, Cr 5 Si 3 undergoes a brittle to ductile transition despite its poor hardness and resistance to deformation, which is attributed to the formation of weak Cr–O bonds. Furthermore, both the presence of vacancy defects and the introduction of oxygen atoms result in Cr 5 Si 3 exhibiting the greater phase stability and better thermal properties. • The influence of vacancies defects and oxygen atoms occupation on physical properties of Cr 5 Si 3 is studied. • These models are stable in Cr 5 Si 3. • The vacancies defects and oxygen atoms occupation induced brittle-to-ductile transition. [ABSTRACT FROM AUTHOR]

In this study, poly (ether ether ketone) (PEEK)/polytetrafluoroethylene (PTFE) composites reinforced with carbon fibers (CFs) and graphite (Gr) were fabricated by compressive molding technology. The friction and wear properties of the PEEK/PTFE composites sliding against Si3N4 balls were investigated using ball-on-disk configuration under dry sliding conditions, and the morphologies of the worn surfaces were also observed with a scanning electron microscope (SEM) and a three-dimensional morphometer. The results indicated that the introduction of CFs significantly improved the tribological properties of the composites, but the friction coefficient of the PEEK/PTFE/CFs composites were higher than the pure PEEK/PTFE composites. However, it was found that a combinative addition of CFs and Gr creates an obvious synergetic effect of improving the friction-reducing and anti-wear abilities of the composites. The mechanisms of the improved tribological properties of the PEEK/PTFE/CFs/Gr composites were discussed based on the analysis of the worn surfaces and tribofilms. [ABSTRACT FROM AUTHOR]

Sophisticated stage-discharge rating curves for radial gates are essential to modernization efforts in water conservancy and irrigation projects. However, it is a challenging hydraulic issue to accurately determine discharges through radial gates, especially when subjected to highly submerged flow conditions. According to the variation trend of jet Froude number and the mechanism of energy dissipation subjected to submerged flows, a new criterion was proposed to subdivide submerged flow into partially submerged and totally submerged flows. Thus, the three stage-discharge equations were developed for free flow, partially submerged flow and totally submerged flow, respectively. With the aid of the experimental data of single radial gate and the field data of multi-radial gates, the proposed discharge calibration method, referred to as the identification method, was tested and verified. The results indicated the discharge prediction accuracies were satisfactory, in which the mean absolute percentage errors were less than 10%. The proposed method is feasible and easily programmed. • Submerged flows through gates are classified as partially and totally submerged flow conditions. • Jet Froude numbers are important indicators to distinguish submerged flow conditions. • Variations of jet Froude number are related to both relative gate openings and submergence ratios. • Stage-discharge relationships should be calibrated for parallel radial gates in practice. [ABSTRACT FROM AUTHOR]

In this article, the differential inductor, widely used as an inductive element, is modified as a resonator. This differential drive inductor resonator (DDIR) can achieve miniature size and extension of second-order mode based on the different electric field distributions on different modes. The second- and fourth-order bandpass filters (BPFs) are designed and fabricated with DDIRs at the promising 5G frequency band of 700-MHz spectrum. The low-loss platform substrate integrated suspended line (SISL) is adopted. The filters are centered at 0.76 GHz/ 0.77 GHz. The footprint areas are only 0.0023 and $0.0052\lambda g^{2}$ without using any lumped elements or substrate with high permittivity. The second-order mode is 5.7/3.92 times the working band without introducing any extra method to broaden the stopband. To improve the rejection of stopband, a T-shaped coupling structure is first proposed on SISL to get the desired location of zeros by weakening the electric coupling and enhancing the magnetic coupling. The comparable version of second- and fourth-order BPFs with T-shaped coupling structure are designed and fabricated. The 20-dB roll-off rate has been decreased by 58.8% and 66.1%. [ABSTRACT FROM AUTHOR]

In this article, an effective method to characterize microwave connectors over temperature is presented, which can be useful for accurate characterization of devices or materials under temperature stress. First, calibration standards made of thermal-stable RF laminate are used, allowing for assuming constant standard coefficients over temperatures and greatly simplifying the process. Second, all the standards are measured concurrently with a four-port VNA for each temperature of interest, avoiding additional errors due to temperature difference or uncertainties caused by connector reconnections in a sequential measurement. Finally, a linear characterization formulation is employed, enabling an error sensitivity analysis. From the analysis, one is able to identify error-resilient standard-equation combinations, to do the data sanity check, and more importantly to determine the optimal standard length toward a wide effective bandwidth. An end-launch connector is characterized at 0 °C–100 °C, showing the effectiveness and usefulness of the proposed method. [ABSTRACT FROM AUTHOR]

Depression has emerged as the predominant psychiatric affliction affecting individuals. Prior research has substantiated the antidepressant properties exhibited by numerous anesthetics. Sevoflurane, a widely utilized inhalant anesthetic in clinical practice, remains relatively uncharted in terms of its specific antidepressant effects. In this study, we used open field test, forced swimming test and novelty-suppressed feeding test to investigate the anxiety and depression-like behaviors in C57BL/6 mice following the inhalation of sevoflurane. We then used western blotting to scrutinized the expression levels of proteins associated with the brain-derived neurotrophic factor (BDNF)-tryosine receptor kinase B (TrkB) pathway in the hippocampus and prefrontal cortex. To further investigate whether sevoflurane exerts antidepressant-like effects via the BDNF-TrkB pathway, we downregulated TrkB expression by administering siRNA into the lateral ventricle. We found that the inhalation of 2.5 % sevoflurane exerted a significant antidepressant-like effect, accompanied by an elevation in p-TrkB expression levels in the hippocampus and prefrontal cortex. Intriguingly, this antidepressant-like effect was abrogated following the downregulation of TrkB expression through the microinjection of siRNA into the lateral ventricle. In conclusion, this study provides evidence supporting the notion that sevoflurane exerts its antidepressant-like effect via the BDNF-TrkB signaling pathway. [ABSTRACT FROM AUTHOR]

To achieve fully flexible microwave devices, we investigated flexible polymers in terms of chemical, mechanical, and electrical properties. Moreover, the fabrication techniques for polymer-based microwave devices have been developed to address chemical adhesion and demolding issues. Finally, based on formulated criteria, we have developed recipes for low-loss (0.001), low-Dk (1.73) flexible dielectric materials and have applied them to the microstrip and CPW transmission lines. The transmission losses of the microstrip and CPW lines are as low as 0.065 and 0.034 dB/cm at 2.5 GHz, respectively, which are comparable to those for rigid PCBs. The effects of various materials on microwave performance have been analyzed, from which we show that the acceptable frequency limits for using our fully flexible microwave devices are 7 GHz for microstrip lines and 10 GHz for CPW lines. The proposed molding process allows us to step out from 2-D PCB designs and build 3-D structures or hybrid PCB-3-D components with a certain freedom in material properties. The new material exhibits unique mechanical properties, which extend the material’s application to other fields. In addition, it has been found that the polymer-based devices have significant performance improvements at elevated temperatures, which can be exploited in a high-temperature application. [ABSTRACT FROM AUTHOR]

We aim to evaluate the safety and feasibility of novel elbow biopsy forceps with a prebent head for sampling biliary strictures in our institution. A total of 24 patients (15 males and 9 females) with biliary stricture who underwent biliary biopsy during endoscopic retrograde cholangiopancreatography (ERCP) using novel elbow biopsy forceps from June 2019 to August 2020 were retrospectively included. The novel biopsy forceps had a head angulation of 30 degrees and were able to cannulate the bile duct and approach the biliary strictures easily to obtain adequate samples. The technical success rate, incidence of adverse events, and consistency of pathological and surgical specimens were assessed. This device was used successfully in all patients. A total of 52 biopsy specimens were obtained from 24 patients, and all specimens could be used for histopathological examination. Seventeen patients were diagnosed with malignancy based on biopsies, and all of them underwent surgical treatment. The histopathological findings of the biopsy specimens were in accordance with the postoperative pathology diagnoses. One of the seven patients was diagnosed with a benign lesion that was proven to be malignant during surgical treatment in the follow-up period. Two patients experienced a single episode of acute pancreatitis and recovered shortly after appropriate treatment. No patients experienced biliary perforation or biliary bleeding. Biopsy using novel elbow forceps in patients with biliary stenosis is feasible and safe. The novel device and related biopsy technique may be widely applied for biliary disease differentiation. [ABSTRACT FROM AUTHOR]

Background: Genome-wide association studies (GWASs) of a large cohort of subjects with chronic obstructive pulmonary disease (COPD) have successfully identified multiple risk genes, including fibroblast growth factor 7 (FGF7). However, the underlying molecular mechanism influencing function of FGF7 and risk of COPD remains further study. Methods: In this study, we replicated the genetic association of variants near the FGF7 gene in 258 Chinese Han patients with COPD and 311 healthy controls. Additionally, we functionally evaluated a candidate causal variant upstream of the FGF7 gene. Results: The most significant association was observed at rs12905203 (P = 5.9 × 10− 3, odd ratio, OR = 1.516) that explains associations of previously reported variants at the FGF7 locus. Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation-quantitative polymerase chain reaction (ChIP-qPCR) assays showed that the risk allele of the variant was bound to activator protein 1 transcription factors (c-Fos and c-Jun) with a significantly reduced affinity and associated with decreased mRNA expression of FGF7 in fibroblast cells at both resting and PMA/Ionomycin-stimulated conditions. Overexpression of c-Fos and c-Jun proteins or stimulation with PMA/Ionomycin significantly increases mRNA expression of FGF7 in fibroblast cells. Bioinformatic analysis showed that the variant overlaps with multiple genetic regulatory marks, suggesting the regulatory DNA element might function as an enhancer for the FGF7 gene. Luciferase enhancer activity assays demonstrated that the DNA sequences carrying the variant produce enhancer activity while the risk allele of the variant reduces its activity. Conclusions: In this study, we demonstrated a consistent association of the FGF7 gene with COPD and mechanistically characterized a candidate functional variant upstream of the FGF7 gene. These data highlighted the important role of the risk variant and the FGF7 gene in influencing risk for COPD. [ABSTRACT FROM AUTHOR]

In this article, full-metal ridged waveguide magic tees are designed and fabricated based on 3-D printing technology. Two kinds of prototypes with different structures and performances are proposed and compared. First, a wideband design based on double-ridged waveguide (DRWG) transmission lines was proposed, and it achieved a measured operational bandwidth of 27%. However, this component has to be split into two parts that are printed separately and then assembled together by screws because the overhang structure cannot satisfy the 3-D printing rules. To overcome this problem, a novel magic tee based on pyramidal ridged waveguide (PRWG) is proposed. In spite of a narrower bandwidth of 8.6%, this design requires a simpler fabrication method and has a lower profile. To the best of our knowledge, the PRWG prototype is the first full-metal magic tee that is fabricated as a whole part without involving any assembling or tuning and, thus, saves processing time and manual work. [ABSTRACT FROM AUTHOR]

A wideband circularly polarized (CP) waveguide array antenna is proposed in this article. The proposed array antenna consists of four antipodally ridged elements and a compact feeding network with two orthogonal septa inserted to a stepped cavity. Both the components are wideband and they can work independently or together. The proposed topology gives a good solution to feed a $2 \times 2$ waveguide subarray which is the basis of large-scale arrays. It exhibits a larger working bandwidth than the array antennas fed by high-order mode cavities. A prototype is fabricated using 3-D printing and milling technologies. Measured results demonstrate a bandwidth of 40.3% from 9.9 to 14.9 GHz, in terms of the reflection coefficients less than −15 dB and the axial ratios smaller than 3 dB. An expanded $8 \times 8$ CP array antenna is explored based on the proposed $2 \times 2$ subarray to show the potentials of our design, and a total efficiency over 78% within a bandwidth of 38.7% is obtained by simulation. [ABSTRACT FROM AUTHOR]

General anaesthetics have been widely applied to induce reversible loss and recovery of consciousness in clinical practice and have been shown to have reliably safe profiles. Since brief exposure to general anaesthetics can result in long-lasting and global changes in neuronal structures and function, these drugs also exhibit strong therapeutic potential for mood disorders. Preliminary and clinical studies have suggested that the inhalational anaesthetic drug sevoflurane might relieve symptoms of depression. However, the antidepressant effects of sevoflurane and the underlying mechanisms remain elusive. In the present study, we confirmed that the antidepressant and anxiolytic effects of inhaling 2.5% sevoflurane for 30 min were comparable to those of ketamine and could be sustained for 48 h. Activation of GABAergic (γ-aminobutyric acidergic) neurons in the nucleus accumbens core by chemogenetics was shown to mimic the antidepressant effects of inhaled sevoflurane, whereas inhibition of these neurons significantly prevented these effects. Considered together, these results suggested that sevoflurane might exert rapid and long-lasting antidepressant effects via modulation of neuronal activities in the nucleus accumbens core nucleus. [ABSTRACT FROM AUTHOR]

Botanical molluscicides for controlling the invasive snail Pomacea canaliculata have attracted worldwide attention because of their cost and environmental friendliness. Aqueous extracts from discarded tobacco leaf (Nicotiana tobacum) were evaluated for molluscicidal activity against different-sized P. canaliculata under laboratory conditions. The results showed that over 90% of the snails died in 1 g/L tobacco extract within 4 days, and the survival of P. canaliculata was inversely proportional to the snail size, tobacco extract concentration and length of exposure time. Adult males were more susceptible to tobacco extract than females. The snails had few chances to feed or mate in 0.5 g/L tobacco extract, and reproduction was greatly limited in 0.2 g/L. The growth of juvenile snails was inhibited in 0.2 g/L tobacco extract, but adults were unaffected. The antioxidant capacity of P. canaliculata in response to tobacco extract can be size- and sex-dependent, and the activities of superoxide dismutase, catalase, and acetylcholinesterase and the contents of glutathione and malondialdehyde were increased in adult males. These results suggest that discarded tobacco leaves can be useful as a molluscicide for controlling the invasive snail P. canaliculata based on its effects on survival, behaviour, food intake, growth performance and antioxidant capacity. [ABSTRACT FROM AUTHOR]

To improve tribological performance of chemically bonded phosphate ceramic coatings, the graphene nano-platelets (GNPs) were selected as the reinforcement. Tribological experiment and the analysis of SEM, EDS and Raman were conducted to clarify the mechanism of graphene on the improvement of tribological performance. It was found that, the worn surface of the coating with GNPs is smoother than the one without GNPs, and these GNPs were extruded out and adhered to the worn surface forming the lubricating tribofilm. Besides, the wear volume decreases with the introduction of GNPs. The reason behind this is that these GNPs can lead to the absorption of the fracture energy, which further can improve the mechanical property of the ceramic. This improvement makes the ceramic more tolerant to damage during the wear. Additionally, the decrease of the internal stress of contact surface because of the large contact surface induced by the smooth worn surface results in the lower wear. The friction coefficient shows the similar trends with the wear volume. The lubricant effect of the adhered lubricating tribofilm stemming from the weak interfacial shear strength between graphene platelets dominantly leads to the decrease in friction coefficient. Besides, the smaller internal stress induced by the smooth surface also contributes to the low friction coefficient because of the direct proportionality between the interfacial shear strength and the contact pressure. [ABSTRACT FROM AUTHOR]

In this study, carbon fiber was modified by 3-Aminopropyl triethoxysilane (KH550) and employed as a functional filler to enhance the wear resistance of chemically bonded ceramic coatings on AISI 304L stainless steel. The chemical structure and morphology of silane-treated carbon fiber (CF) were characterized using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). It was found that the surface of CF became rough due to the grafting of KH550, which improved the bonding strength between CF and ceramic matrix. The tribological performance of the ceramic coatings with silane-treated CF was evaluated using a ball-on-disc method. The results showed that the friction coefficient and wear rate of the ceramic coatings decreased with the increase of the content of silane-treated CF. These improvements were attributed to the strong bonding strength between silane-treated CF and ceramic matrix, which could consume more fracture energy and block the diffusion pathway of cracks. This study provides new insights into the design and optimization of wear-resistant ceramic coatings reinforced with modified carbon fiber for potential engineering applications. [ABSTRACT FROM AUTHOR]

• Calycosin had neuroprotection on neurons injured by oxygen-glucose deprivation reperfusion in vitro. • Calycosin exerts neuroprotective effects against ischemia–reperfusion injury in vivo. • The ERK signaling pathway participates in the neuroprotective role of calycosin. Calycosin is a natural product extracted from some plant families and exhibits various biological properties. But the effect of calycosin on cerebral ischemia–reperfusion injury has not been fully elucidated. In this study, the neuroprotective effect of calycosin treatment on the differentiated SH-SY5Y cells exposed to OGD was evaluated using MTT and flow cytometry. Rats that were pretreatment with calycosin were subjected to MCAO, neurological behavior scores and brain infarct volume were evaluated. The protein expression of pERK/ERK were assessed using Western blot. siRNA-pERK and U0126 were administered to investigate the impact of the ERK pathway on calycosin preconditioning. The results demonstrated the neuronal viability in the calycosin-treated SH-SY5Y cells increased significantly, and the rate of apoptosis decreased compared with the Oxygen-glucose deprivation only SH-SY5Y cells. Calycosin pretreatment reduced infarct volume and improved neurological outcome in rats subjected to MCAO. Administration of calycosin increased the ratio of pERK/ERK expression, which was down-regulated in ischemia–reperfusion group. Down-regulation of pERK/ERK significantly attenuated the neuroprotective effect induced by calycosin pretreatment in vitro and in vivo. We concluded calycosin treatment could induce a neuroprotective effect against ischemia, which was related to the regulation of the ERK1/2 pathway. [ABSTRACT FROM AUTHOR]

Geographic visualization is essential for explaining and describing spatiotemporal geographical processes in flow fields. However, due to multi-scale structures and irregular spatial distribution of vortices in complex geographic flow fields, existing two-dimensional visualization methods are susceptible to the effects of data accuracy and sampling resolution, resulting in incomplete and inaccurate vortex information. To address this, we propose an adaptive Line Integral Convolution (LIC) based geographic flow field visualization method by means of rotation distance. Our novel framework of rotation distance and its quantification allows for the effective identification and extraction of vortex features in flow fields effectively. We then improve the LIC algorithm using rotation distance by constructing high-frequency noise from it as input to the convolution, with the integration step size adjusted. This approach allows us to effectively distinguish between vortex and non-vortex fields and adaptively represent the details of vortex features in complex geographic flow fields. Our experimental results show that the proposed method leads to more accurate and effective visualization of the geographic flow fields. [ABSTRACT FROM AUTHOR]

A neural network (NN)-based hybrid physical model for gallium nitride high-electron-mobility transistors (GaN HEMTs) is proposed. In this model, the artificial NN (ANN) is used to construct the terminal charge densities, which is linked with device model’s RF and dc performance using the MIT Virtual Source (MVS) theory. A detailed parameter extraction and optimization method for this hybrid model is proposed as well. The parameter extraction starts from S-parameters with the consideration of access region resistances. The particle swarm optimization (PSO) is used to optimize extraction results. After that, a two-hidden-layer ANN is constructed to model the obtained source-end terminal charge density ($q_{\mathrm {is}}$) and drain-end terminal charge density ($q_{\mathrm {id}}$). Then, the ANN-based $q_{\mathrm {is}}$ and $q_{\mathrm {id}}$ are used to construct the hybrid model under the framework of the MVS theory. The trapping effects and self-heating effects are also considered in this hybrid model. This hybrid model is built and verified in the Advanced Design System (ADS). The proposed hybrid model has better scalability than the traditional ANN-based models. It is also more accurate than the traditional MVS-based physical model. This hybrid model presents satisfactory agreement between measured and simulated current–voltage (IV), S-parameters, load—pulls, and power sweeps. [ABSTRACT FROM AUTHOR]

The process of J / ψ → Λ Λ ̄ is studied using 1. 0 × 1 0 1 2 J / ψ Monte Carlo (MC) events at s = 3. 0 9 7  GeV with a fast simulation software at future Super Tau Charm Facility (STCF). The statistical sensitivity for CP violation is determined to be the order of (1 0 − 4) by measuring the asymmetric parameters of the Λ decay. Furthermore, the decay of J / ψ → Λ Λ ̄ also serves as a benchmark process to optimize the detector responses using the interface provided by the fast simulation software. [ABSTRACT FROM AUTHOR]

Anesthesia inhibits neural activity in the brain, causing patients to lose consciousness and sensation during the surgery. Layers 2/3 of the cortex are important structures for the integration of information and consciousness, which are closely related to normal cognitive function. However, the dynamics of the large-scale population of neurons across multiple regions in layer 2/3 during anesthesia and recovery processes remains unclear. We conducted simultaneous observations and analysis of large-scale calcium signaling dynamics across multiple cortical regions within cortical layer 2/3 during isoflurane anesthesia and recovery in vivo by high-resolution wide-field microscopy. Under isoflurane-induced anesthesia, there is an overall decrease in neuronal activity across multiple regions in the cortical layer 2/3. Notably, some neurons display a paradoxical increase in activity during anesthesia. Additionally, the activity among multiple cortical regions under anesthesia was homogeneous. It is only during the recovery phase that variability emerges in the extent of increased neural activity across different cortical regions. Within the same duration of anesthesia, neural activity did not return to preanesthetic levels. To sum up, anesthesia as a dynamic alteration of brain functional networks, encompassing shifts in patterns of neural activity, homogeneousness among cortical neurons and regions, and changes in functional connectivity. Recovery from anesthesia does not entail a reversal of these effects within the same timeframe. [Display omitted] • Innovative simultaneous observation of cortical neuron ensemble dynamics across brain regions in vivo. • Cortical layer 2/3 neuron ensembles exhibit different classification features across states of consciousness. • Homogeneous activity among cortical regions under anesthesia contrasts with increased variability during recovery. • Large-scale neural activity shows that cortical connectivity changes dynamically during anesthesia and recovery. [ABSTRACT FROM AUTHOR]

The overall effectiveness of nonlinear optical processes along extended nonlinear media highly depends on the fulfillment of the phase‐matching condition for pump and generated fields. This is traditionally accomplished by exploiting the birefringence of nonlinear crystals requiring long interaction lengths (cm‐scale). For nonbirefringent media and integrated photonic devices, modal phase matching can compensate the index mismatch. Here, the various interacting waves propagate in transverse modes with appropriate phase velocities, but they suffer from a low refractive index contrast and cm‐scale interaction lengths. This work harnesses modal phase matching for third‐harmonic generation (THG) in plasmonic waveguides using an organic polymer (poly[3‐hexylthiophene‐2,5‐diyl]) as the nonlinear medium. One demonstrates experimentally an effective interaction area as small as ≈ 0.11 µm2 and the phase‐matched modal dispersion results in THG efficiency as high as ≈ 10–3 W‐2 within an effective length scale of ≈ 4.3 µm. THG also shows a strong correlation with the polarization of the incident laser beam, corresponding to the excitation of the antisymmetric plasmonic modes, corroborating that plasmonic modal phase matching is achieved. This large reduction in device area of orders of magnitude is interesting for various applications where space is critical (e.g., device integration or on‐chip applications). [ABSTRACT FROM AUTHOR]

In the research topic of three-dimensional (3-D) synthetic aperture radar (SAR) imaging, the sparsity-enforcing techniques offer promise in shortening the sensing time and improving the reconstruction accuracy. However, many of them only explore the sparse prior of 3-D SAR images, which leads to biased estimations in cases of non-sparse scenarios. To remedy this problem, we propose a new network with learned low-rank and sparse priors, i.e., LLRS-Net, to obtain improved reconstructions from sparsely sampled 3-D SAR echoes. In our scheme, a two-stage reconstruction algorithmic framework (LSRA) is derived based on sparse and low-rank priors, wherein the first stage recovers the measurements from their limited observations by exploring the low-rank prior, while the second estimates the final 3-D SAR images with a fast iterative optimization. Theoretically inspired by LRSA, the LLRS-Net is designed into a cascaded network structure. In LLRS-Net, the trainable weights serve as independent variables and control the algorithmic hyperparameters via regularizing functions, ensuring a well-conditioned updating tendency. By end-to-end training, the network weights are updated automatically under the guidance of a compound loss function constraining both the outputs of two stages. Finally, the methodology is validated on simulations and measured experiments. These results show that the proposed framework outperforms many state-of-the-art imaging algorithms in recovering 3-D SAR images from incomplete echo data. [ABSTRACT FROM AUTHOR]

A compact and cost-effective antenna array that enables a 2-D full 90° cone-metric-space beam-scanning is designed in this article. To achieve this unique function, a resonant-type phase-shifter, which is characterized by small size and large phase-shifting ability, is proposed. Primary and secondary feed networks are designed in series configurations, in which resonant-type phase-shifters are periodically inserted. The beam-scanning of this antenna array is solely controlled by frequency in one dimension, while it is controlled by a combination of frequency and resonant-type phase-shifter in the other dimension. A validation is demonstrated by a $6\times12$ antenna array prototype operating from 4.45 to 4.95 GHz. Measurement results indicate a full 360° scanning range in the azimuth plane and a ±45° scanning range in the elevation plane. When the beam is toward the broadside direction, the radiation efficiency is estimated to be around 29%, while measured sidelobe levels (SLLs) are smaller than −19 dB in both E-plane and H-plane. Thanks for the proposed control mechanism of simplified 2-D beam-scanning, this method is considered cost-effective and very suitable to be deployed in low-cost systems. [ABSTRACT FROM AUTHOR]

The potential of oleosins to act as carriers for recombinant foreign proteins in plant cells has been established. Using the oleosin fusion technology, the protein can be targeted to oil bodies in oilseeds by fusing it to the N- or C-terminus of oleosin. In this study, aFGF was expressed in Arabidopsis thaliana seeds via oleosin fusion technology. A plant-preferred aFGF gene was synthesized by optimizing codon usage and was fused to the C-terminus of the A. thaliana 18.5 kDa oleosin gene. The fusion gene was driven by the phaseolin promoter to confer seed-specific expression of the human acidic fibroblast growth factor in A. thaliana . The T-DNA region of the recombinant plasmid pKO-aFGF was introduced into the genome of Arabidopsis thaliana by the floral dip method. The aFGF protein expression was confirmed by SDS-PAGE and western blotting. The biological activity showed that oil bodies fused to aFGF stimulated NIH/3T3 cell proliferation activity. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a miniaturized rat-race coupler with harmonic suppression. The proposed coupler only takes 15.1% of the area of the corresponding conventional rat-race coupler. By replacing the traditional transmission line with the proposed stub-loaded transmission line equivalently, the coupler performances can be retained and size can be reduced significantly at the same time. In addition, due to the transmission zero introduced by the stubs, the harmonic suppression is also improved. To verify the effectiveness of the substitution, the design equations are derived for analysis. Finally, the proposed coupler is fabricated for experimental verification, and a good match is found between the simulation and measurement results. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:190-193, 2015 [ABSTRACT FROM AUTHOR]

Background: As a crucial node of the corticolimbic model, the striatum has been demonstrated in modulating emotional cues in pediatric bipolar disorders (PBD), the striatal distinction in structure and function between PBD-I and PBD-II remains unclear.Methods: MRI data of 36 patients in PBD-I, 22 patients in PBD-II and 19 age-gender matched healthy controls (HCs) were processed. Here, we investigated structural and functional alterations of 8 subregions of striatum (bilateral nucleus accumbens, caudate, putamen and globus pallidus) by analyzing MRI data.Results: We found volume reduction of the right pallidum, the significant positive correlation between the number of episodes and the functional connectivity between left pallidum and right caudate in PBD-I patients, abrupted prefrontal-striatal-thalamic functional connectivity in PBD-I group and decreased functional connectivity in PBD-II relative to HCs and PBD-I.Limitations: Future studies should enroll more subjects and adopt a longitudinal perspective, which could help to discover striatum structural or functional alterations during subject-specific clinical progress in different states.Conclusions: Results of the present study confirmed that structural and functional abnormality of striatum may be helpful in identifying PBD clinical types as distinctive biomarkers. The interruptions of the prefrontal-striatal-thalamic circuits may provide advantageous evidence for expounding the role of striatum in bipolar disorders etiology. Thus, potential mechanisms of dysfunction striatum need to be formulated and reconceptualized with multimodal neuroimaging studies in future. [ABSTRACT FROM AUTHOR]

The real-time accurate description of all spatial features of railway and their spatiotemporal relationships is a crucial factor in realizing comprehensive management and related decision-making within the entire life cycle of railways. Nevertheless, available spatiotemporal data models mainly use static historical sequence data, which are insufficient to support multi-source heterogeneous real-time sensed data; they lack a systematic depiction of the interactive relationships among multiple feature entities, and are limited to low-level descriptive analysis. Therefore, this study proposes a data-model-knowledge integrated representation data model for a digital twin railway, which explicitly describes the spatiotemporal, and interaction relationships among railway features through a conceptual knowledge graph. This study first analyzes the characteristics of railway features from above ground to underground, and then constructs a conceptual model to clearly describe the complex relationships among railway features. Secondly, a logical model is developed to illustrate the basic data structure. Thirdly, an ontology model is constructed as a basic framework for further deepening the domain knowledge graph. Finally, considering the prevention of landslides as an example, it demonstrates the abundant spatiotemporal relationships among railway related features. The results of this study bring more clear understanding of the complex interactive relationships of railway entities. [ABSTRACT FROM AUTHOR]

A 60 GHz 8 × 8 dual‐polarized aperture‐coupled magneto‐electric (ME) dipole antenna array in low temperature co‐fired ceramic (LTCC) technology is proposed. Taking advantage of the LTCC technology of high integration, the antenna array is composed of three parts, including the wideband ME dipole elements, dual‐polarized strip‐line series feeding network and low‐loss gap waveguide (GWG) feeding network. The ME dipole antenna element is fed by aperture coupling with 45° rotation. Two separate orthogonal strip lines are located right below the aperture to realize dual polarization performance. The simulated −10 dB impedance bandwidth of the dual‐polarized antenna element is 50–66.5 GHz with an isolation lower than −20 dB for two input ports. By employing the proposed radiating element, a 4 × 4 wide‐band dual‐polarized antenna subarray is realized by using strip‐line series‐feed technology. A compact hybrid low‐loss feeding network is realized by combing the GWG technology with the strip‐line series feed technology. For demonstration, one prototype was fabricated. The measured impedance bandwidth is 14.2% and 16.7% respectively for dual polarizations with |S11| < −8 dB, and the port isolation is lower than −20 dB over the entire frequency band of interest. [ABSTRACT FROM AUTHOR]

Geometry-induced resonant modes with intrinsic broad beam coverage are synthesized within step-shaped dielectric resonator antennas (DRAs). Following the idea of mode fusion, a synthesized mode inherits and combines the modal features from several conventional ones of regular DRAs. Superior flexibility and design freedom in beam shaping are thus obtained, leading to a 3 dB beamwidth exceeding 200° in both main planes. To form such a broad-beam mode, three regular higher-order modes from rectangular DRAs are chosen and merged. Their modal radiation patterns have fine complementation, meanwhile, they are readily excited by a shared feed. To further demonstrate the mechanism of mode fusion, the modal field distribution of the presented DRAs is analyzed. A design guide is presented as well. [ABSTRACT FROM AUTHOR]

Alterations of brain signal complexity may reflect brain functional abnormalities. In adolescent bipolar disorder (ABD) distribution of brain regions showing abnormal complexity in different mood states remains unclear. We aimed to analyze brain entropy (BEN) alteration of functional magnetic resonance imaging (fMRI) signal to observe spatial distribution of complexity in ABD patients, as well as the relationship between this variation and clinical variables. Resting-state fMRI data were acquired from adolescents with bipolar disorder (BD) who were in manic (n = 19) and euthymic (n = 20) states, and from healthy controls (HCs, n = 17). The differences in BEN among the three groups, and their associations with clinical variables, were examined. Compared to HCs, manic and euthymic ABD patients showed increased BEN in right parahippocampal gyrus (PHG) and left dorsolateral prefrontal cortex (DLPFC). There was no significant difference of BEN between the manic and the euthymic ABD groups. In manic ABD patients, right PHG BEN exhibited significantly positive relationship with episode times. Increased BEN in right PHG and left DLPFC in ABD patients may cause dysfunction of corticolimbic circuitry which is important to emotional processing and cognitive control. The positive correlation between PHG BEN and episode times of manic ABD patients further expressed a close association between brain complexity and clinical symptoms. From the perspective of brain temporal dynamics, the present study complements previous findings that have reported corticolimbic dysfunction as an important contributor to the pathophysiology of BD. BEN may provide valuable evidences for understanding the underlying mechanism of ABD. • Adolescent bipolar disorder(ABD) showed increased brain entropy(BEN) in parahippocampal gyrus/dorsolateral prefrontal cortex. • There is a close association between brain complexity(BEN) and clinical symptom(episode times) in manic ABD. • Altered brain temporal dynamics of the present study provided further proof of vital role of corticolimbic dysfunction in ABD. • BEN alteration may be not mood state specific, and it provide valuable evidence for the underlying mechanism of ABD. [ABSTRACT FROM AUTHOR]

Anal fistula is a common and serious complication of Crohn's disease (CD). A sufficiently suitable animal model that may be used to simulate this disease is yet to be established. The aim of the present review was to summarize the different characteristics and experimental methods of commonly used animal models of CD with anal fistula. Electronic databases were searched for studies reporting on the use of this type of animal model. A total of 234 related articles were retrieved, of which six articles met the inclusion criteria; these were used as references for the present review article. The characteristics of the animal models, the advantages and disadvantages of the modeling methods and the similarities with patients with CD and anal fistula were summarized and analyzed. The evidence suggests that a sufficiently suitable animal preclinical model requires to be established. [ABSTRACT FROM AUTHOR]

In this communication, a novel 2-D beam scanning antenna array is designed and fabricated in metallic 3-D printed technology with high integration and reduced fabrication complexity in millimeter waves. The array is composed of four leaky wave antennas and a Butler matrix based on groove gap waveguide (GWG) technology. One dimension of the beam scanning performance is realized by moving one row of pins along the groove based on the GWG concept. Meanwhile, the sidelobe levels of the radiation patterns are reduced to −20 dB by controlling the height and distance of pins along groove. The beam direction of the low sidelobe leaky wave antenna changes from 110° to 140°, while the frequency shifts from 25 to 35 GHz. Another dimension of the beam scanning capability is realized with the Butler matrix in groove GWGs. The design of this Butler matrix is based on the coupling between multilayered groove GWGs. By this means, the low sidelobe leaky wave antennas are connected directly to the Butler matrix with no more transition structures. The main beam direction of the antenna array shifts from −41° to 41°, when the exciting ports change in order. The simulated and measured port isolations are lower than −15 dB over the frequency band of 27–35 GHz, and they match well with each other. [ABSTRACT FROM AUTHOR]

A compact bandpass filter (BPF) with a wide upper stopband using a short‐circuited microstrip coupled‐line hairpin resonator is presented. The equivalent transmission‐line circuit model is developed to analyse the performances of the proposed filter. The feeding lines are capacitively coupled to the resonator at the point which divides the fingers of the hairpin into two segments at a ratio of 1:2. As a result, the first harmonic appears at the frequency which is five times the fundamental frequency. In the final design with a grounding via hole, three transmission zeros are generated to improve the skirt effect. Therefore, a compact BPF with a wide upper stopband could be achieved. Finally, the proposed filter is fabricated to verify the design principles, and the measured results agree well with the predicted ones. [ABSTRACT FROM AUTHOR]

This article analyzes the bias dependence of gate‐drain capacitance (Cgd) and gate‐source capacitance (Cgs) in the AlGaN/GaN high electron mobility transistors under a high drain‐to‐source voltage (Vds) from the perspective of channel shape variation, and further simplifies Cgd and Cgs to be gate‐to‐source voltage (Vgs) dependent only at high Vds. This method can significantly reduce the number of parameters to be fitted in Cgd and Cgs and therefore lower the difficulty of model development. The Angelov capacitance models are chosen for verifying the effectiveness of simplification. Good agreement between simulated and measured small‐signal S‐parameters, large‐signal power sweep, and power contours comprehensively proves the accuracy of this simplification method. [ABSTRACT FROM AUTHOR]

Dynamic evolution of ponatinib-resistant mutations in BCR-ABL1-positive leukaemias revealed by next-generation sequencing Keywords: BCR-ABL1; tyrosine kinase inhibitors; next-generation sequencing; drug-resistant mutation; compound mutations EN BCR-ABL1 tyrosine kinase inhibitors next-generation sequencing drug-resistant mutation compound mutations e113 e116 4 12/07/20 20201201 NES 201201 Tyrosine kinase inhibitors (TKIs) targeting BCR-ABL1 oncoprotein revolutionized the therapy of leukaemias carrying this fusion. The black line represents the BCR-ABL1 transcript level (%). gl Case 2 (Fig 1B) was a seven-year-old boy with a diagnosis of BCR-ABL1-positive B-ALL. With the increase of CML patients who underwent long-term TKI therapy and the increasing application of TKIs in BCR-ABL1-positive B-ALL, as well as the extensive use of sequential TKIs, the dynamics of resistant clones has become more complicated. [Extracted from the article]