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Waste bamboo fiber was obtained from the paper-making industry, and bamboo fiber-activated carbon was prepared by employing the KOH activation method. The bamboo fiber-activated carbon was used as the absorbent to absorb the crystal violet in water.

Visual servoing is a control method that utilizes image feedback to control robot motion, and it has been widely applied in unmanned aerial vehicle (UAV) motion control. However, due to field-of-view (FOV) constraints, visual servoing still faces challenges, such as easy target loss and low control efficiency. To address these issues, visual servoing control for UAVs based on the deep reinforcement learning (DRL) method is proposed, which dynamically adjusts the servo gain in real time to avoid target loss and improve control efficiency. Firstly, a Markov model of visual servoing control for a UAV under field-of-view constraints is established, which consists ofquintuplet and considers the improvement of the control efficiency. Secondly, an improved deep Q-network (DQN) algorithm with a target network and experience replay is designed to solve the Markov model. In addition, two independent agents are designed to adjust the linear and angular velocity servo gains in order to enhance the control performance, respectively. In the simulation environment, the effectiveness of the proposed method was verified using a monocular camera.

To ensure the success of large-scale sporting events, prevent the contamination of food by prohibited substances, and evaluate the risk of foodborne stimulants and other hormones in food, it is necessary to establish a high-throughput, rapid, and accurate detection method for foodborne stimulants and other hormones. In this study, a QuEChERS method is proposed for the simultaneous determination of 44 foodborne stimulants and 6 progestogens using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The analyzed foodborne stimulants include 19

Background: Primary biliary cholangitis (PBC) is a complex disease with high heritability. We investigated the association between human leukocyte antigen (HLA)-DRB1 alleles and PBC in families and sporadic cases to evaluate the genetic components of the disease. Methods: We performed whole exome sequencing in three PBC families. We genotyped HLA-DRB1 and calculated the association between HLA-DRB1 alleles and the encoding amino acid sequences with the clinical features. Results: Ten variants harboured the HLA-DRB1 gene associated with PBC. DRB1 x07:01, 14:01 and 14:05 were highly increased in PBC. Ten coding region polymorphisms were associated with PBC that encode the amino acid variants of HLA-DR beta 54, beta 59 and beta 66 located in the peptide-binding site of the MHC molecule. Glutamine at position 54 was confirmed as a risk amino acid, verifying the results of familial aggregation analysis of PBC families. Discussion: Familial aggregation analysis indicated that HLA-DRB1 is a candidate gene for the risk of disease course. Considering that amino acid variations are critical to peptide-binding properties, they underlie the major component of MHC association with PBC. (c) 2021 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Immune cell infiltration occurs in the tumor microenvironment (TME) and influences cancer progression through interaction with tumor cells. Runt-related transcription factors (RUNXs), RUNX1-3, are the master regulators of development and differentiation and are all important to the development of immune cells. However, the role of RUNXs in the immune cells of TME remains unclear. In this study, we first used online related databases and related LGG data from TCGA and CGGA to conduct bioinformatics analysis, which confirmed that RUNXs were significantly and positively correlated with immune infiltration in multiple tumors, especially in low-grade glioma (LGG) and there was the highest correlation between RUNXs and the progress and prognosis of LGG. Furthermore, the functional enrichment analysis revealed that RUNXs might be involved in the inflammatory and immune responses of the biological processes, and RUNXs were tightly associated with the multiple immune checkpoint molecules. Subsequent results confirmed that RUNX1, as an independent prognostic factor for LGG, may target interferon-gamma receptor 2 (IFNGR2) to regulate glioma cell proliferation, invasion, and migration. Besides,we also found that the expression levels of RUNX1 and IFNGR2 were significantly reduced, and their correlation was enhanced in the IDH-mutant subtype. Patients with a high expression of RUNX1 and/or IFNGR2 (HH/H) in the IDH-mutant subtype showed poorer prognosis and significantly increased infiltration of M2 macrophages. This finding implied the possible key role of RUNX1 in the differentiation of IDH mutant subtypes as well as in the formation of tumor microenvironment (TME) infiltration signatures by monitoring IFNGR2.

Alkaline phosphatase (ALP) is a type of enzyme that widely exists in various tissues of the human body; it plays an important role in regulating many cell functions. The development of a sensitive and accurate tool to detect the changes of ALP activity in organisms can contribute to research in the fields of biochemistry, cytology, clinical medicine, etc. In this paper, a small organic molecule-based ratiometric fluorescent probe (FCP) was designed based on the hydroxyl electron-donating group in fluorescein-coumarin protected by the phosphate group. ALP can trigger the fluorescence change through the enzyme-catalyzed cleavage of phosphoryl ester groups, and the ratio of ALP can be measured at wavelengths of 465 nm and 530 nm. The probe had high selectivity and sensitivity to ALP, and the detection limit measured under the optimal conditions in an aqueous medium reached 0.006 mU/mL. The ALP activity of human serum samples was determined using the probe and found to be in good agreement with that measured using commercial ALP kits. Finally, the probe was also successfully applied to image ALP in living hepatocytes with good selectivity and sensitivity.

The porous carbons with high specific surface area and excellent electrochemical properties were prepared using three types of green needle coke as raw materials. Electrochemical performances of the porous carbons derived from different microstructure green needle coke were investigated. The XRD and Raman spectra demonstrated that the content of the ordered carbon microcrystals were decreased and the content of amorphous and cross-linked structure were increased in the porous carbons with comparison to the raw materials. The results of N2 adsorption–desorption analysis verified that the content of ordered microcrystalline structure in the raw materials evidently influence the specific surface area and pore size distribution of the porous carbons. The porous carbon with 1665 m2 g−1 specific surface area and 2.89 nm average pore size has shown that the specific capacitance was 288 F g−1 at the current density 1 A g−1. Furthermore, the capacity retention was 94.93% and the Coulombic efficiency was 92.87% after 5000 charge/discharge cycles.

The use of quadrotors is proliferating across many civil applications, including those in the areas of the Internet of Things (IoT) and communications. Attitude control plays an important role in these applications, and designing a quadrotor attitude controller is a challenging task. Recently, several design methods for the attitude controller were presented with an accurate model. However, during the flying state, the quadrotor may be affected by several factors that cause unpredictable disturbances to the model. As a result, an accurate model of disturbances is difficult to establish. To address this problem, in this paper, a novel linear feedforward all-coefficient adaptive control (FACAC) strategy based on characteristic modeling is proposed. The contributions of our work are as follows. First, a second-order characteristic model of the quadrotor attitude control is established based on the dynamic equations. Second, an all-coefficient adaptive control (ACAC) controller that consists of the golden-section adaptive control law, the logic integral, and logic differential control laws is designed. The feedforward maintaining and tracking control law is integrated into the ACAC controller to shorten the settling time. Finally, extensive simulation results demonstrate that the performance of the proposed FACAC controller outperforms the state-of-the arts.

Matrix metalloproteinase 2 (MMP-2) is a crucial biomarker of tumor growth, invasion and metastasis. In the present study, a core-satellite magnetic-fluorescent-plasmonic nanosensor (FMNS@Au) was constructed through biological self-assembly to generate localized SERS "hot spots" and an efficient FRET system for the sensitive determination of MMP-2 activity in a SERS-fluorescence dual-mode assay. In this hybrid nanosensor, a biotin-labeled peptide containing a specific MMP-2 substrate (PLGVR) was employed as a bridge for the assembly of gold nanoparticles (AuNPs) and avidin functionalized fluorescent-magnetic nanospheres (FMNS). The modified RB on FMNS served as a Raman reporter and a donor of FRET, while the AuNPs assembled on FMNS acted as SERS substrates and acceptors of FRET. In the presence of MMP-2, the SERS "hot spot" effect was weakened and the FRET system was disrupted through enzymatic cleavage of PLGVR, resulting in a reduction of SERS signal and the recovery of fluorescence emission. Importantly, this combination of SERS and fluorescence assay methods in the dual-mode nanosensor broadened the detection range for MMP-2 to 1-200 ng mL

As a very serious problem for control systems, actuator saturation often leads to an unstable system. The maneuvering flight of quadrotors may lead to actuator saturation, which commonly affects the flight quality, including trajectory-tracking accuracy. Quadrotors usually adopt double-closed-loop control, of which the outer loop is the position control used to calculate the desired attitude angle and the inner loop is the attitude control used to generate control actions for the vehicle. To address actuator saturation during the maneuvering flight of quadrotors, an attitude controller based on the conditioned super-twisting algorithm (CSTA) was designed. The sign functions in CSTA were replaced by a hyperbolic tangent function, which suppresses the chattering of CSTA. In order to improve the rapidity of the improved controller, the tanh-CSTA (TCSTA), a gain adjustment factor was utilized. The rapidity and smoothness of the controller can be satisfied by adjusting the gain factor. Additionally, a sliding surface was designed according to the characteristics of the quadrotor control structure, so that the TCSTA controller can be applied to the second-order system. The performances of the designed improved controller were simulated using MATLAB, and the results showed that the designed controller is more robust than the PID controller. Moreover, compared with the CSTA controller, the chattering of the designed controller was obviously suppressed without reducing the control accuracy.

ObjectiveIt was to evaluate the anti-inflammatory effect of ursodeoxycholic acid (UDCA) on concanavalin A (ConA)-induced immune hepatitis in mice and determine the molecular mechanism. MethodsFemale C57BL/6J mice were randomly classified into Control, ConA, and ConA+UDCA groups. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured. Quantitative real-time polymerase chain reaction (qRT-PCR) was applied to detect the expression of hepatic inflammatory factor tumor necrosis factor-α (TNF-α), and receptor-interacting protein (RIP)3 mRNA. The percentages of immune cells in liver and spleen were detected and analyzed by flow cytometry. ResultsUDCA decreased the serum ALT and AST levels, down-regulated the expression of cytokine TNF-α mRNA and necroptosis marker RIP3 mRNA in the liver tissue, up-regulated the percentages of immunomodulatory myeloid-derived suppressor cells (MDSCs) in liver and spleen tissues, and down-regulated the accumulation of liver macrophages of mice with immune hepatitis. ConclusionsUDCA attenuates ConA-induced hepatic inflammation in mice by reducing the production of hepatic inflammatory factors, inhibiting the expression of necroptosis signal proteins in hepatocytes, down-regulating the accumulation of hepatic macrophages, and increasing the percentage of MDSCs with immunomodulatory properties.

The number of death due to cancer-related diseases each year is at the alarming level and is constantly growing. Tools that can effectively and conveniently detect cancer cell apoptosis can play a significant role in cancer research, cancer therapy, and other related industries. Herein, we fabricated, for the first time, an ultrasensitive, disposable, self-enhanced off-on electrochemiluminescence (ECL) biosensor based on ternary Ru-PEI@PCN-333(Al) system to determine caspase-3 activity, the biomarker of apoptosis. The biosensor had a low detection limit of 0.017 pg/mL and was able to enhance the ECL emission and stability. A solid-state (SS) ECL strategy was adopted to overcome the relatively weak ECL emission due to the long distance between electrochemiluminophore and electrode surface. The analysis requires only one incubation step, which can significantly reduce the operational complexity and time. The biosensor had higher sensitivity, and the off-on ECL mode was achieved using caspase-3 as a switch. The on-site and rapid detection capability of the biosensor was achieved by the introduction of disposable screen-printed electrodes (SPEs). This study lays a foundation for the development of more advanced, ingenious, portable and reliable ECL devices for biosensing not only caspase-3, but also other bioanalytes.

Due to the complex terrain of the electrical power plant, it is difficult for the inspection UAV to distinguish the landing site from the environment and achieve accurate landing in the process of inspection. Aiming at the above problems, this paper designs an accurate landing system based on vision guidance for the inspection UAV. Firstly, the black circular block is designed as the landing sign. Then, vision sensors and embedded processing units on the UAV are utilized to acquire images of the ground in real time, and the image filtering and the adaptive threshold segmentation are used to separate the landing sign from the background. Next, the position of the landing sign is detected by the ellipse detection algorithm, and the UAV is guided to land according to the position of landing signs. Finally, the autonomous landing experiments under different scenarios are carried out, the experimental results show that the system proposed in this paper has stable and reliable performance. Among them, the maximum landing deviation of the system is 11.5 cm, and the autonomous landing time is stable within one minute, which meets the requirements of specific projects.

Plasma sheath generated by fierce friction between hypersonic aircraft and air causes severe interference on communication between ground and aircraft once the frequency of electromagnetic wave is lower than the frequency of plasma. However, effects that plasma sheath exerts on antenna window can be mitigated via application of a sandwich structure which consists of alternant medium layers with positive and negative relative permittivity, where meta-material and plasma sheath serve as negative relative permittivity layer. Transmission performance of antenna window covered by plasma sheath will increase harshly within certain frequency range of wave propagation, which is known as window frequency. The typical effect of metamaterial surface on the transmission performance of antenna window in window frequency is discussed in the paper, and simulation results are included as validation of the effect.

Direct Z-scheme Bi

Introduction Traumatic spinal cord injury (SCI) is a life-altering event. Motor vehicle accidents and falls are common causes of traumatic SCI, and SCI outcomes may be affected by patients' ages and injury sites. This study aimed to investigate the factors associated with unfavorable in-hospital outcomes, focusing on the impact of patients' ages and SCI lesion sites. Methods Data of 25,988 patients hospitalized with traumatic SCI in the US National Inpatient Sample (NIS) database from 2005 to 2014 were extracted and analyzed. Univariate and multivariate logistic regression analyses were performed to determine the factors associated with SCI outcomes, including in-hospital deaths, adverse discharge, and prolonged hospital stays. Results Multivariate analysis revealed that the oldest ages (>65 years) were significantly associated with increased in-hospital mortality compared with the youngest ages at all lesion sites (cervical, odds ratio [OR]: 5.474, 95% confidence interval [CI]: 4.465 to 6.709; thoracic, OR: 5.940, 95% CI: 3.881 to 9.091; and lumbosacral, OR: 6.254, 95% CI: 2.920 to 13.394). Older ages were also significantly associated with increased adverse outcomes at all sites (cervical, OR: 2.460, 95% CI: 2.180 to 2.777; thoracic, OR: 2.347, 95% CI: 1.900 to 2.900; and lumbosacral, OR: 2.743, 95% CI: 2.133 to 3.527). Intermediate ages (35 to 64) were also significantly associated with increased in-hospital death and adverse discharge at cervical and thoracic SCIs, but not at lumbosacral sites. Discussion For hospitalized patients with traumatic SCI, older age independently predicts worse in-hospital outcomes, with greatest effects seen in patients aged 65 years and older. Study findings suggest that extra vigilance and targeted management strategies are warranted in managing SCI patients aged 65 years and older during hospitalization.

Research on characteristics of helicopter rotor blade tip vortex (BTV) is one of the key elements for helicopter rotor aerodynamic characteristics research. The existing traditional computational fluid dynamics (CFD) based detection methods of vortex core area in the flow field mainly use points or lines in the flow field for calculation. However, the traditional CFD-based model is complex, huge computational cost and without effective vortex core model. So the manual analysis will be necessary in some scenarios to simplify the work of vortex detection, such as vortex region detection for helicopter rotor BTV in domestic. In order to decrease the workload of manual analysis, we draw on the advanced research results in the field of computer vision and machine learning, especially target detection, and firstly propose a vortex region detection method in blade tip vortex based on You Only Look Once (YOLO) network. First of all, the vortex region is marked in flow field images under the guidance of domain experts to construct the vortex data set. Secondly, we propose an improved model based on yolo v3-tiny. Finally, the self-built vortex data set is used to train models. Experiments show that the CNN-based method has better result than traditional methods.

It has been universally believed that the soluble and insoluble components of coal tar pitch obtained by solvent extraction were good precursors to prepare mesophase cokes. The microstructure and macro properties of mesophase cokes derived from the soluble and insoluble components are varied in general. In order to study the differences and correlations between the microstructure and macro properties of mesophase cokes, 16 kinds of component in two categories have been prepared mesophase cokes as the raw materials. Briefly, Scanning electron microscope (SEM), Polarizing Microscope (PM), Raman spectroscopy, X-Ray Diffraction (XRD), thermogravimetry (TG) and Micro-strength intensity (MSI) have been used to characterize microstructure and macro properties of cokes. In fact, the graphite structure in extract-based cokes is larger and more orderly than that in residue-based cokes. The MSI of residue-based cokes (66 ∼ 81%) is higher than that of extract-based cokes (53 ∼ 60%), while Tmax (615 ∼ 645 ℃ and 680 ∼ 715 ℃) of the two are opposite. In a word, the results indicate that all data of the two categories of cokes go to bipolar distribution. And the results of this work were helpful for understanding and providing direction for the evaluation of cokes used to prepare isotropic and anisotropic graphite.