Substrateless Packaging for a D-Band MMIC Based on a Waveguide with a Glide-Symmetric EBG Hole Configuration

This paper presents a novel substrateless packaging solution for the D-band active e mixer MMIC module, using a waveguide line with a glide-symmetric periodic electromagnetic bandgap (EBG) hole configuration. The proposed packaging concept has the benefit of being able to control signal propagation behavior by using a cost-effective EBG hole configuration for millimeter-wave- and terahertz (THz)-frequency-band applications. Moreover, the mixer MMIC is connected to the proposed hollow rectangular waveguide line via a novel wire-bond wideband transition without using any intermediate substrate. A simple periodical nail structure is utilized to suppress the unwanted modes in the transition. Additionally, the presented solution does not impose any limitations on the chip\u27s dimensions or shape. The packaged mixer module shows a return loss lower than 10 dB for LO (70-85 GHz) and RF (150-170 GHz) ports, achieving a better performance than that of traditional waveguide transitions. The module could be used as a transmitter or receiver, and the conversion loss shows good agreement in multiple samples. The proposed packaging solution has the advantages of satisfactory frequency performance, broadband adaptability, low production costs, and excellent repeatability for millimeter-wave- and THz-band systems, which would facilitate the commercialization of millimeter-wave and THz products

Building up Graphene-Based Conductive Polymer Composite Thin Films Using Reduced Graphene Oxide Prepared by γ

In this paper, reduced graphene oxide (RGO) was prepared by means of γ-ray irradiation of graphene oxide (GO) in a water/ethanol mix solution, and we investigated the influence of reaction parameters, including ethanol concentration, absorbed dose, and dose rate during the irradiation. Due to the good dispersibility of the RGO in the mix solution, we built up flexible and conductive composite films based on the RGO and polymeric matrix through facile vacuum filtration and polymer coating. The electrical and optical properties of the obtained composite films were tested, showing good electrical conductivity with visible transmittance but strong ultraviolet absorbance

Preparation of Hydroxyapatite/Tannic Acid Coating to Enhance the Corrosion Resistance and Cytocompatibility of AZ31 Magnesium Alloys

Hydroxyapatite/tannic acid coating (HA/TA) were prepared on AZ31 magnesium alloys (AZ31) via chemical conversion and biomimetic methods. The characterization and properties of the coating were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), corrosion testing, MC3T3-E1 cell proliferation assay, and MC3T3-E1 cell morphology observation. The results showed that tannic acid as an inducer increased the number of nucleation centers of hydroxyapatite and rendered the morphology more uniform. Compared to bare AZ31 magnesium (Mg) alloys (Ecorr = −1.462 ± 0.006 V, Icorr = (4.8978 ± 0.2455) × 10−6 A/cm2), the corrosion current density of the HA/TA-coated magnesium alloys ((5.6494 ± 0.3187) × 10−8 A/cm2) decreased two orders of magnitude, and the corrosion potential of the HA/TA-coated Mg alloys (Ecorr = −1.304 ± 0.006 V) increased by about 158 mV. This indicated that the HA/TA coating was effectively protecting the AZ31 against corrosion in simulated body fluid (SBF). Cell proliferation assays and cell morphology observations results showed that the HA/TA coating was not toxic to the MC3T3-E1 cells

Effectiveness of Chinese medicine formula Huashibaidu granule on mild COVID-19 patients: A prospective, non-randomized, controlled trial

Background: The effectiveness and safety of Huashibaidu granule (HSBD) in treating mild Corona Virus Disease 2019 (COVID-19) patients infected with SARS-CoV-2 remain to be identified. We aimed to evaluate the effectiveness of HSBD in mild COVID-19 patients. Methods: A prospective, non-randomized, controlled study in mild COVID-19 patients was conducted in Shanghai, from April 8 to May 6, 2022. The enrolled patients were diagnosed as mild COVID-19. Finally, 360 patients received HSBD, and 368 patients received TCM placebo (administered orally 20 g twice daily for 7 days). The primary endpoints were the negative conversion rate of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and the negative conversion time. Secondary endpoints included the hospitalized days and the improvement in the clinical condition. Results: The negative conversion rate of SARS-CoV-2 at 7 days posttreatment in the HSBD group was higher than that in the control group (95.28% vs. 82.61%, P < 0.001). The median negative conversion time in the HSBD group was markedly decreased by 2 days compared with the control group (3 [3–6] vs. 5 [4–7], P < 0.001). In addition, the median hospitalized day was shortened in the HSBD group by 1 day compared with the control group (6 [4–7] vs. 7 [5–9], P < 0.001). The clinical improvement rate (275/360 [76.39%]) in the HSBD group within 7 days was significantly higher than that (203/368 [55.16%]) in the control group (P < 0.001). The improvement of symptom scores in the HSBD group was higher than that in the control group (2 [1–4] vs. 1 [1–2], P < 0.001). No severe adverse events occurred. Conclusions: Our study suggested that HSBD effectively increased the negative conversion rate of SARS-CoV-2 and shortened the negative conversion time and hospitalized days in mild COVID-19 patients. Clinical trial registration: Chinese Clinical Trial Registry, ChiCTR220005866

Multi-Relation Attention Network for Image Patch Matching

International audienceDeep convolutional neural networks attract increasing attention in image patch matching. However, most of them rely on a single similarity learning model, such as feature distance and the correlation of concatenated features. Their performances will degenerate due to the complex relation between matching patches caused by various imagery changes. To tackle this challenge, we propose a multi-relation attention learning network (MRAN) for image patch matching. Specifically, we propose to fuse multiple feature relations (MR) for matching, which can benefit from the complementary advantages between different feature relations and achieve significant improvements on matching tasks. Furthermore, we propose a relation attention learning module to learn the fused relation adaptively. With this module, meaningful feature relations are emphasized and the others are suppressed. Extensive experiments show that our MRAN achieves best matching performances, and has good generalization on multi-modal image patch matching, multi-modal remote sensing image patch matching and image retrieval tasks

Cross-Flow Catalysis Behavior of a PVDF/SiO2@Ag Nanoparticles Composite Membrane

A blend of Polyvinylidene Fluoride (PVDF) and SiO2 microspheres in N,N-Dimethylformamide (DMF) underwent phase inversion to form a PVDF/SiO2 membrane with SiO2 microspheres in the membrane’s pores. Subsequently, the SiO2 microspheres have been used as platforms for in site Ag nanoparticles (NPs) synthesis, forming a composite membrane. Benefitting from the full exposure of Ag NPs to the reactants, the composite membrane shows high catalytic reactivity when catalyzing the reduction of p-nitrophenol under a cross-flow. The catalytic reaction follows the first-order kinetics, and the reaction rate increases with an increase in the amount of Ag NPs in the membrane, the reaction temperature, and the operating pressure. What is more, highly purified products can be produced and separated from the reactants in a timely manner by using the composite membrane

Ancient Herbal Formula Mahuang Lianqiao Chixiaodou Decoction Protects Acute and Acute-on-Chronic Liver Failure via Inhibiting von Willebrand Factor Signaling

Background: Acute liver failure (ALF) and acute-on-chronic liver failure (ACLF) are characterized by systemic inflammation and high mortality, but there is no effective clinical treatment. As a classic traditional Chinese medicine (TCM) formula, MaHuang-LianQiao-ChiXiaoDou decoction (MHLQD) has been used clinically for centuries to treat liver diseases. Methods: The LPS/D&minus;GalN-induced ALF mice model and the CCl4+LPS/D&minus;GalN-induced ACLF mice model were used to observe the therapeutic effects of MHLQD on mice mortality, hepatocytes death, liver injury, and immune responses. Results: MHLQD treatment significantly improved mice mortality. Liver injury and systemic and hepatic immune responses were also ameliorated after MHLQD treatment. Mechanistically, proteomic changes in MHLQD-treated liver tissues were analyzed and the result showed that the thrombogenic von Willebrand factor (VWF) was significantly inhibited in MHLQD-treated ALF and ACLF models. Histological staining and western blotting confirmed that VWF/RAP1B/ITGB3 signaling was suppressed in MHLQD-treated ALF and ACLF models. Furthermore, mice treated with the VWF inhibitor ADAMTS13 showed a reduced therapeutic effect from MHLQD treatment. Conclusions: Our study indicated that MHLQD is an effective herbal formula for the treatment of ALF and ACLF, which might be attributed to the protection of hepatocytes from death via VWF/RAP1B/ITGB3 signaling

A Study on the Degree of Amidoximation of Polyacrylonitrile Fibers and Its Effect on Their Capacity to Adsorb Uranyl Ions

Amidoximation of polyacrylonitrile (PAN) fibers was studied by reacting them with hydroxylamine. The chemical structure, mechanical intensity, and morphologies of PAN and amidoximated PAN (AO-PAN) fibers were evaluated by Fourier transform infrared spectroscopy, tensile tests, dynamic mechanical analysis, and scanning electron microscopy, respectively. A higher degree of amidoximation resulted in a higher conversion ratio (CR) of the nitrile group and a higher density of the amidoxime group, while also reducing the mechanical intensity of the fibers. During amidoximation, a hydrogel layer formed on the fiber surface by bonding with H₂O molecules, increasing the diameter of the AO-PAN fibers. The layer thickness increased as the CR of the AO-PAN fibers’ nitrile group was increased. The hydrogel layer decreased the adsorption capability by hindering the diffusion of uranyl ions to the interior of the AO-PAN fibers. Therefore, a CR of about 10.8% would provide an appropriate balance between the mechanical properties and the adsorption capability

Graphene Oxide Transparent Hybrid Film and Its Ultraviolet Shielding Property

Herein, we first reported a facile strategy to prepare functional Poly­(vinyl alcohol) (PVA) hybrid film with well ultraviolet (UV) shielding property and visible light transmittance using graphene oxide nanosheets as UV-absorber. The absorbance of ultraviolet light at 300 nm can be up to 97.5%, while the transmittance of visible light at 500 nm keeps 40% plus. This hybrid film can protect protein from UVA light induced photosensitive damage, remarkably