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The disorder flow of seeds caused by the collision in the seed-guiding tube is one of the important reasons for the reduction of seeding uniformity. For this problem, a seed-guiding tube with brachistochrone considering the influence of friction was presented in this paper. By analyzing kinetics and rotating the equation coordinate system, brachistochrone under the condition of friction was obtained and applied to the design of the structural parameters of the grain conductor of T-groove furrowing device, and a discrete element model of the grain conductor and wheat was established, thus single-factor simulation analysis and quadratic regression orthogonal rotation combination simulation tests were conducted to explore the optimal combination of parameters. The test results showed that the seed-guiding tube had a brachistochrone radius of 14.708 mm, a linear length of 500 mm and a working speed of 4 km/h, and the seed spacing offset dispersion degree and the seed lateral offset dispersion degree were 12.26 and 8.53 respectively, which had a high seeding uniformity. The results of the bench validation test showed that the coefficients of variation of the two test evaluation indexes between the bench test results and the virtual simulation results were 10.20% and 8.62% respectively, therefore the simulation results could be used for the optimization of the seed guide tube.

What Is Known and Objective. CYP2C19 is an important influencing factor for voriconazole trough plasma concentration (Cmin); however, it is not verified in Child–Pugh C (CP-C) cirrhosis patients, and no voriconazole dosage regimen is recommended for these patients in the package insert. This retrospective study identified CYP2C19 and other factors influencing voriconazole Cmin for CP-C cirrhosis, and obtained an appropriate method of application of voriconazole for them. Methods. A total of 66 patients with CP-C cirrhosis who accepted voriconazole therapy were involved. The voriconazole Cmin, clinical characteristics, CYP2C19 genotype, and adverse effects (AEs) were recorded and analyzed. Results. Unlike other research studies, voriconazole Cmin was not different among normal metabolizers (NMs), intermediate metabolizers (IMs), and poor metabolizers (PMs) of the CYP2C19 enzyme in CP-C cirrhosis ( P > 0.05). The maintenance dose regimen for voriconazole was the only independent influencing factor for Cmin ( P = 0.045; OR = 3.753; 95% CI, 1.029–13.694). At about 1/3 of the recommended maintenance dose, only 16.7% (8/48) had Cmin >5.5 μg/mL, 4.5% (3/48) had Cmin

Chemoresistance remains a major challenge in gastric cancer (GC). Chromodomain helicase DNA-binding protein 4 (CHD4) mediated chromatin remodeling plays critical roles in various tumor types, but its role in chemoresistance in GC remains uncharacterized.CHD4 expression was examined by immunohistochemistry and Western blotting. The role of CHD4 on cell proliferation and chemoresistance of GC was examined in vitro and in vivo. Immunoprecipitation and liquid chromatography-mass spectrometry were used to identify CHD4-binding proteins and a proximity ligation assay was used to explore protein-protein interaction.Chemoresistance is associated with upregulation of CHD4 in the tumor tissues of GC patients. Overexpression of CHD4 increased chemoresistance and cell proliferation. Knockdown of CHD4 induced cell apoptosis and cell cycle arrest. CHD4 mediates the decrease of the intracellular concentration of cisplatin by inducing drug efflux. Additionally, CHD4 promotes the interaction between ERK1/2 and MEK1/2, resulting in continuous activation of MEK/ERK pathway. Knockdown of CHD4 in GC increased sensitivity to chemotherapy and suppressed tumor growth in a mouse xenograft model.This study identifies CHD4 dominated multi-drug efflux as a promising therapeutic target for overcoming acquired chemoresistance in GC.

Water-evaporation-induced electricity generation provides an ideal strategy to solve growing energy demand and supply power for self-powered systems because of its advantages of a highly spontaneous process, continuous power generation, and low cost. However, the reported evaporation-induced generators are limited to working only in deionized (DI) water, leading to a low output power. Herein, we utilize a modified multiple ion mode to demonstrate that the streaming potential can be optimized in microchannels filled with salt solution and achieve an enhanced evaporation-induced output power in salt solution by a generator based on honeycomb-structured reduced graphene oxide (rGO) film with abundant interconnected microchannels. This generator enables an around 2-fold open-circuit voltage (Voc) and a 3.3-fold power density of 0.91 μW cm-2 in 0.6 M NaCl solution compared to that in DI water. Experiments evidence that the honeycomb structure with abundant interconnected microchannels plays a key role in achieving high and stable output power in salt solution because of its large specific surface area and excellent ion-exchange capacity. Notably, it can work at all times of day and night for more than 240 h in natural seawater, delivering a stable Voc of ∼0.83 V with a power density of 0.79 μW cm-2. This study expands a working solution for water-evaporation-induced electricity generation from DI water to natural seawater, advancing a great step toward practical applications.

Recently, Co2P has been deemed to be a low-cost and fruitful activator for promoting photocatalytic hydrogen (H2) production activity for graphitic carbon nitride (g-C3N4). Nevertheless, almost all...

Electrochemical nitrogen fixation provides an environmentally friendly strategy for producing ammonia (NH3) under ambient conditions. However, an inexpensive and efficient electrocatalyst for the electrocatalytic nitrogen reduction reaction (NRR) under ambient conditions is still needed. Herein, we report an efficient non-noble-metal electrocatalyst consisting of large scaled-up monocrystalline 3R MoS2, which is first utilized as an electrocatalyst for the NRR under ambient conditions. The NRR performance can be optimized via improving the electrochemically active surface area (ECSA) of MoS2. The NH3 yield rate and FE of MoS2-700 reach 8.8 μg h−1 mgcat−1 and 1.9%, respectively. Notably, 3R MoS2-700 shows excellent stability, with the negligible fluctuation of electrocatalytic activity after being recycled seven times. This study may provide a new strategy for structuring efficient electrocatalysts for the NRR.

The diffuse-type gastric cancer (DGC) is a subtype of gastric cancer (GC) associated with low HER2 positivity rate and insensitivity to chemotherapy and immune checkpoint inhibitors. Here, we identify urokinase-type plasminogen activator receptor (uPAR) as a potential therapeutic target for DGC. We have developed a novel anti-uPAR monoclonal antibody, which targets the domains II and III of uPAR and blocks the binding of urokinase-type plasminogen activator to uPAR. We show that the combination of anti-uPAR and anti–Programmed cell death protein 1 (PD-1) remarkably inhibits tumor growth and prolongs survival via multiple mechanisms, using cell line–derived xenograft and patient-derived xenograft mouse models. Furthermore, uPAR chimeric antigen receptor–expressing T cells based on the novel anti-uPAR effectively kill DGC patient–derived organoids and exhibit impressive survival benefit in the established mouse models, especially when combined with PD-1 blockade therapy. Our study provides a new possibility of DGC treatment by targeting uPAR in a unique manner.

O-glycosylation is a widespread post-translational modification of proteins. Aberrant O-glycosylation is a hallmark of cancer. Here, we show that the polypeptide N-acetylgalactosamine-transferase 1 (

Limb motion capture is essential in human motion-recognition, motor-function assessment and dexterous human-robot interaction for assistive robots. Due to highly dynamic nature of limb activities, conventional inertial methods of limb motion capture suffer from serious drift and instability problems. Here, a motion capture method with integral-free velocity detection is proposed and a wearable device is developed by incorporating micro tri-axis flow sensors with micro tri-axis inertial sensors. The device allows accurate measurement of three-dimensional motion velocity, acceleration, and attitude angle of human limbs in daily activities, strenuous, and prolonged exercises. Additionally, we verify an intra-limb coordination relationship exists between thigh and shank in human walking and running, and establish a neural network model for it. Using the intra-limb coordination model, dynamic motion capture of human lower limbs including thigh and shank is tactfully implemented by a single shank-worn device, which simplifies the capture device and reduces cost. Experiments in strenuous activities and long-time running validate excellent performance and robustness of the wearable device in dynamic motion recognition and reconstruction of human limbs., Current wearable motion capture technologies are unable to accurately detect dynamic motion of human limbs due to drift and instability problems. Here, the authors report a wearable motion capture device combining tri-axis velocity sensor and inertial sensors for accurate 3D limb motion capture.

In order to make full use of the diversity of sample information in the tracking process and improve the generalization ability of the tracker, this paper integrates the object model prediction results on the basis of the Staple algorithm, and applies weighted bands to the simple linearity of different predictive response results in the algorithm. To the uncertainties, a new adaptive response factor graph fusion method with weight coefficients is proposed, which effectively improves the reliability of the video target tracking algorithm. Theoretical analysis and experimental simulation show that the proposed algorithm is more accurate and robust than the classical Staple algorithm, and it maintains high real-time performance.

Low solar light absorption and high electron–hole pair recombination are still the main challenges for solar energy conversion. Here, we design a plasmonic nanoparticle (NP)-film with a unique structure combining the advantages of a Au NP and film, which exhibits strong broadband absorption from the visible to near-infrared (NIR) wavelength range. In addition, the high density of sub-1 nm inter-particle gaps in the Au NP-film supports electromagnetic field enhancement of several orders of magnitude that greatly promotes the generation and separation of electron–hole pairs. Accordingly, the plasmonic NP-film-assisted photocatalyst (TiO2/90Au/TiO2) leads to an 88-fold increase in the photocurrent density at 0.75 V vs. RHE in 25% methanol solution under visible-NIR light irradiation (λ > 420 nm) compared to a TiO2 film, which is higher than those of the ever reported Au/TiO2 photocatalysts in the entire visible-NIR range. Our finding indicates a promising way to explore full solar spectrum photocatalysts, which can be easily extended to other energy conversion applications.

Precision planting has been proven to be an effective method for seeding row crops with uniform seed spacing, which favors crop yields. However, most precision planters were developed for low field operating speeds. In this study, a mechanical seed-metering device was developed with double-setting seed pickers, which allows high-quality planting at high field operating speeds. A discrete element model (DEM) was used to examine the effects of the design parameters on the metering performance, as indicated by the quality index (Iq), miss index (Imiss), and multiples index (Imult). Based on the model results, a seed-metering device was fabricated with the optimal design parameters and tested in laboratory conditions for model validation. Results showed that the critical parameters for the seed picker design were the lengths of the first and second setting plates (L1 and L2, respectively) and the seed cell and seed holder angles (a and ß, respectively). The Iq was generally high and the Imiss and Imult were generally low over the ranges of L1 from 15.5 to 17.5 mm, L2 from 4.6 to 5.5 mm, a from 57.5° to 65.0°, and ß from 50.0° to 70.0°. The most influential factors were ß and L2 and their interactions. The best performance, represented by the highest Iq, occurred at L2 = 5.18 mm and ß = 61.9°, where the Iq was 99.59%. The model results agreed well with the test results, as demonstrated by the low relative error (2.5%). Keywords: DEM, Modeling, Precision metering, Quality index, Seed, Travel speed.

Recently, direct formic acid fuel cells (DFAFCs) which possess superior advantages such as a low operating temperature, light environmental pollution and high energy density, have been considered as one of the power generation technologies with a bright prospect. Herein, bimetallic PdAg nanoparticles (NPs) with different particle sizes were successfully produced via an easy one-pot solvothermal co-reduction synthetic route and their electrocatalytic performance for formic acid oxidation (FAO) were further investigated. In our strategy, the size of PdAg NPs can be easily controlled by only varying the concentration of precursors. The larger sized PdAg alloy (9.5 nm, noted as PdAg-L) was obtained at a low concentration of precursors, while the smaller PdAg alloy (3.7 nm, named as PdAg-S) was separated from the reaction system with higher solubility by centrifugation. The electrocatalytic activity and stability of the obtained PdAg NPs could be well optimized when incorporated with carbon (C), which is owing to a synergetic effect. The PdAg-S/C exhibits the highest mass activity with around 1.6 times that of PdAg-L/C and 2 times that of commercial Pd/C, which can be attributed to its larger ECSA and lower adsorption energy of the intermediate to facilitate the direct oxidation of HCOOH molecule.

To describe the epidemiological and clinical characteristics of patients with Corona Virus Disease 2019 (COVID-19) in Beijing. To analyze the application of corticosteroids in patients with severe pneumonia. We collected information on demographic characteristics, exposure history, clinical characteristics, corticosteroids use, and outcomes of the 65 confirmed cases of COVID-19 at Fifth Medical Center of PLA General Hospital from Jan 20 to Feb 23, 2020. The final follow-up date observed was April 15th, 2020. The number of patients with mild, general, severe, and critical type were 10 (15.38%), 32 (49.23%), 8 (12.31%), and 15 (23.08%), respectively. The median incubation period was 6 days. Notable outliers were 1 patient at 16 days and 1 patient at 21 days. In lymphocyte subgroup analysis, decreases in total, T, CD4, and CD8 lymphocytes were more common as the disease worsened (All P P = 0.0215) but did not affect T lymphocyte (P = 0.0796). There was no significant difference between patients using lower dose (≤ 2 mg/kg day) and higher dose (> 2 mg/kg day) mPSL in inhibiting IL-6 production (P = 0.5856). Thirty of 31 patients (96.77%) had stopped mPSL due to improvement of pneumonia. Virus RNA clearance time lengthened with disease progression (P = 0.0001). In general type, there was no significant difference in virus clearance time between patients with (15, 12–19 days) and without (14.5, 11–18 days) (P = 0.7372) mPSL use. Lymphocyte, especially T lymphocyte, in severe and critical patients showed a dramatic decrease. Application of lower dose corticosteroids (≤ 2 mg/kg day) could inhibit IL-6 production (a representative of cytokines) as effectively as a higher dose. Proper use corticosteroids in general type patients did not delay virus clearance.

Electrochemical nitrogen reduction reaction (NRR) provides a facile and sustainable strategy to produce ammonia (NH3) at ambient conditions. However, the low NH3 yield and Faradaic efficiency (FE) are still the main challenges due to the competitive hydrogen evolution reaction (HER). Herein, a three‐phase electrocatalyst through in situ fabrication of Au nanoparticles (NPs) located on hydrophobic carbon fiber paper (Au/o‐CFP) is designed. The hydrophobic CFP surface facilitates efficient three‐phase contact points (TPCPs) for N2 (gas), electrolyte (liquid), and Au NPs (solid). Thus, concentrated N2 molecules can contact the electrocatalyst surface directly, inhibiting the HER since the lowered proton concentration and overall enhancing NRR. The three‐phase Au/o‐CFP electrocatalyst presents an excellent NRR performance with high NH3 yield rate of 40.6 µg h−1 mg−1 at −0.30 V and great FE of 31.3% at −0.10 V versus RHE (0.1 m Na2SO4). The N2‐bubble contact angle result and cyclic voltammetry analysis confirm that the hydrophobic interface has a relatively strong interaction with N2 bubble for enhanced NRR and weak electrocatalytic activity for HER. Significantly, the three‐phase Au/o‐CFP exhibits excellent stability with a negligible fluctuation of NH3 yield and FE in seven‐cycle test. This work provides a new strategy for improving NRR and simultaneously inhibiting HER., A three‐phase electrocatalyst with abundant three‐phase contact points (TPCPs) is achieved by direct in situ fabrication of Au NPs on hydrophobic carbon fiber electrode, demonstrating high ammonia yield rate (40.6 µg h−1 mg−1) and high Faradaic efficiency (31.3%).

Objective To describe the epidemiological and clinical characteristics of patients with Corona Virus Disease 2019 (COVID19) in Beijing. To analyze the treatment strategies especially the application of corticosteroids in patients with severe pneumonia.Methods We collected information on demographic characteristics, exposure history, clinical characteristics, treatment and outcomes of the 65 confirmed cases of COVID19 at the 5th Medical Center of PLA General Hospital from Jan 20 to Feb 23, 2020. The final follow-up date observed was Feb 29, 2020. Results The number of patients with mild, general, severe, and critical type were 10 (15.38%), 32 (49.23%), 8 (12.31%), and 15 (23.08%), respectively. The median incubation period was 6 days. Notable outliers were 1 patient at 16 days and 1 patient at 21 days. In lymphocyte subgroup analysis, decreases in total, T, CD4, and CD8 lymphocytes were more common as the disease worsened (All PP=0.0215) but did not affect T lymphocyte (P=0.0796). There was no significant difference between patients using lower dose (≤2mg/kg.d) and higher dose (>2mg/kg.d) methylprednisolone in inhibiting IL-6 production (P=0.5856). Thirty of 31 patients (96.77%) had stopped methylprednisolone due to improvement of pneumonia. Virus RNA clearance time lengthened with disease progression (P=0.0001). In general type, there was no significant difference in virus clearance time between patients with (15, 12-19 days) and without (14.5, 11-18 days) (P=0.7372) methylprednisolone use. Conclusions Lymphocyte, especially T lymphocyte, in severe and critical patients showed a dramatic decrease. Application of lower dose corticosteroids (≤2mg/kg.d) could inhibit IL-6 production (a representative of cytokines) as effectively as a higher dose. Proper use corticosteroids in general type patients did not delay virus clearance. Authors Fangfang Liu and Chengcheng Ji contributed equally to this work.

AP65 doped with different elements are rolled into the anode plates for Mg-air battery and higher-power seawater activated battery. The discharge and corrosion behaviour of their cross- section surfaces (CS) and rolling surfaces (RS) is systematically studied and the results show that the RS consisting of (0001) crystallographic planes have lower corrosion rates and inhibit the self- discharge at 180 mA cm−2, whereas the CS with ( 11 2 ¯ 0 ) and ( 10 1 ¯ 0 ) planes provide higher anodic efficiencies at 10 mA cm−2 and possess stronger discharge activity. Furthermore, the dissolution mechanisms of different surfaces are also elucidated based on microstructure characterization and electrochemical response.

In this letter, a robust object tracking method is proposed, which is divided into two parts: robust tracker based on complementary feature fusion with channel reliability, and reliable validator based on convolutional neural network. Compared with the existing tracking algorithms, our algorithm tracks the target more robustly and accurately, and suppresses template drift problems effectively. Experimental results on the standard benchmark show that our algorithm can compete with advanced algorithms and achieve a better level.

Solar energy has been considered as one of the most promising sustainable energy sources to meet the current energy demands. Plasmonic metal nanostructures, possessing unique localized surface plasmon resonance effects, hold particular strengths in enhancing incident light trapping and extending optical response range across the full solar spectrum. The integration of plasmonic metal nanostructures into photocatalyst systems offers huge opportunities to maximize the utilization of solar energy and improve the conversion efficiency of solar energy into available chemical energy, especially hydrogen fuel cells. Herein, recent research efforts on the applications of plasmonic metal nanostructures in photocatalytic, photoelectrochemical (electro‐assisted photocatalytic), and photo‐assisted electrocatalytic water splitting, including the hydrogen evolution reaction and the oxygen evolution reaction, are highlighted. In addition, the relevant structure design, mechanism exploration, and performance promotion are summarized and discussed.

Here we describe a plasmon-enhanced fluorescence substrate based on poly(methyl methacrylate) (PMMA)-coated, large-area Au@Ag nanorod arrays. The use of a PMMA medium enables precise control of the competition between enhancing and quenching processes as a function of the distance between Au@Ag nanorods and dye molecules. At the optimal PMMA layer thickness of 56 nm (for which the distance between nanoparticles and dye molecules is 16 nm), a maximum enhancement of fluorescence of up to ∼ 27 times is measured. The competition mechanism between enhancing and quenching processes depends on the thickness of the PMMA layer, which has been confirmed by consistent experimental and theoretical modeling results. Notably, the micropatterned metal-enhanced fluorescence (MEF) substrate exhibits high uniformity and reproducibility. The simple spin-coating process described herein provides an attractive, scalable, and low-cost strategy to produce uniform and reproducible large-area MEF substrates that can potentially be used in many fields, such as biochips, diagnostics, and photonics.

Building a complex structure system of conductive polymers without a complicated fabricating process is a long-awaited goal to improving the functional photoresponse properties of conductive polymers. In this study, we demonstrate that the photoresponse of polypyrrole (PPy)-based photodetector devices with an ultrathin polymer layer can be chemically modulated by simply immersing the devices into an alkaline solution. After alkaline treatment, the pyrrole unit transforms into a quinoid structure. Characteristics of current–voltage reveal an increased photosensitivity with several orders of magnitude when decreasing the applied bias voltage. Furthermore, ultrathin PPy belts with a width of 100 nm exhibit ultra-high photosensitivites of roughly 1000 (unit) and photoresponsivities of 54.3 A W−1 due to the high surface area ratio of the nanobelts.

Infrared small target detection plays a significant role in modern infrared search and track systems(IRST) and has also received much attention. Based on this background, a novel approach to detect infrared small target based on salient region extraction (SRE) and gradient vector processing (GVP) is proposed in this paper. This approach consists of three parts: pre-processing based on fast median filtering, SRE based on spectral residual algorithm (SRA) processing and similarity analysis algorithm (SAA) processing, and target detection in infrared gradient vector field (IGVF). Both theory and experimental have shown that the proposed algorithm can detect the target more robustly and accurately, and spend less time processing compared with the existing infrared small target detection algorithm. It is a small infrared target detection method with superior performance and good application prospect.