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Betel palms and mango plantations are two crucial commercial crops in tropical agricultural areas. Accurate spatial distributions of these two crops are essential in tropical agricultural regional planning and management. However, the characteristics of small patches, scattering, and perennation make it challenging to map betel palms and mango plantations in complex tropical agricultural regions. Furthermore, the excessive features of very-high-resolution (VHR) imaging might lead to a reduction in classification accuracy and an increase in computation times. To address these challenges, we selected five feature selection (FS) methods (random forest means a decrease in accuracy (RFMDA), ReliefF, random forest-recursive feature elimination (RFE), aggregated boosted tree (ABT), and logistic regression (LR)) and four machine learning algorithms (random forest (RF), support vector machine (SVM), classification and regression tree (CART), and adaptive boosting (AdaBoost)). Then, the optimal combinations of FS and machine learning algorithms suited for object-oriented classification of betel palms and mango plantations were explored using VHR Gaofen-2 imagery. In terms of overall accuracy, all optimal classification schemes exceeded 80%, and the classifiers using selected features increased the overall accuracy between 1% and 4% compared with classification without FS methods. Specifically, LR was appropriate to RF and SVM classifiers, which produced the highest classification accuracy (89.1% and 89.88% for RF and SVM, respectively). In contrast, ABT and ReliefF were found to be suitable FS methods for CART and AdaBoost classifiers, respectively. Overall, all four optimal combinations of FS methods and classifiers could precisely recognize mango plantations, whereas betel palms were best depicted by using the RF-LR method with 26 features. The results indicated that combination of feature selection and machine learning algorithms contributed to the object-oriented classification of complex tropical crops using Gaofen-2 imagery, which provide a useful methodological reference for precisely recognizing small tropical agricultural patterns. [ABSTRACT FROM AUTHOR]

Rechargeable Zn-MnO2 batteries with mild and nearly neutral aqueous electrolytes have shown great potential for large-scale energy storage because of their high safety, low cost, environmental friendliness and high energy density. However, MnO2 cathode materials usually have disadvantages such as low capacity and poor cycling stability, which limit the development of Zn-MnO2 batteries. In this study, mesoporous MnO2 nanospheres were prepared by in situ Mg ion pre-intercalation via a simple chemical method. The prepared MnO2 shows a high reversible capacity (247 mA h g−1 at 0.3 A g−1), excellent cycling stability (a capacity retention of 93% over 800 cycles at 0.8 A g−1) and good rate performance. The GITT, in situ EIS, ex situ XRD, ex situ XPS and ex situ SEM show that the zinc storage mechanism of MnO2 should be H+/Zn2+ co-intercalation/de-intercalation. This research could provide specific inspiration and promotion for the development and mechanism research of high-performance rechargeable Zn-MnO2 batteries. [ABSTRACT FROM AUTHOR]

It was the first time to report the aggregation induced emission (AIE) of acetaldehyde (AA) on the surface of carbonized polymer dots (CPDs) with the auxiliary of Tb3+. Based on the AIE of AA, a turn-off–on fluorescence method was established for AA detection using the porous CPDs-Tb3+ system. The one-pot hydrothermal method was used to obtain CPDs, using milk and polyethyleneimine (PEI) as precursors. In the presence of Tb3+, CPDs aggregated immediately and even forming precipitate, and the fluorescence intensity decreased obviously. AA can effectively embed on the surface of CPDs-Tb3+ due to the porous structure. AA displayed obviously blue fluorescence with excitation wavelength at 370 nm (emission peak at 460 nm), while there was no fluorescence peak when excited at 460 nm. In the CPDs-Tb3+ solution, AA exhibits obvious fluorescence enhancement effect (λex 460 nm, λem 545 nm). And then, AA can be determined by the turn-off–on system based on the linear relationship between fluorescence enhancement and the concentration of AA ranging from 0.04 mM to 42.48 mM. The limit of detection (LOD) was 0.02 mM. The turn-off–on system was successfully applied to determine AA in wine samples. The strategy may be exploited to monitor AA in more drinking or foodstuff samples. [ABSTRACT FROM AUTHOR]

Emotions are generally considered to be important elements of consumer behavior, but little research has investigated the link between emotions and consumers' adoption behavior relating to electric vehicles (EVs). To address this gap, this study examines the roles of emotions in EV adoption intention by focusing on pride and guilt and explores the impact of perceived value on these causal processes. We proposed a research model and empirically tested it using 405 survey responses collected from China. The structural equation modeling analysis results indicate that both pride and guilt significantly affect EV adoption intention, and the effect of pride is stronger than that of guilt. Perceived value mediates the relationships between emotions and EV adoption behavior. We also found differences between men and women. The findings of this study contribute to a better understanding of the role of emotions in consumers' EV adoption behavior, and provide recommendations for the promotion of EVs. [ABSTRACT FROM AUTHOR]

Camurati‐Engelmann disease (CED) is a rare autosomal‐dominant skeletal dysplasia caused by mutations in the transforming growth factor‐β1 (TGFB1) gene. In this study, a retrospective review of patients with CED evaluated at Peking Union Medical College Hospital in Beijing, China, between November 30, 2000 and November 30, 2020 was conducted. Data including demographic data, manifestations, and examination results were characterized. Furthermore, bone geometry, density, and microarchitecture were assessed and bone strength was estimated by HR‐pQCT. Results showed the median age at onset was 2.5 years. Common manifestations included pain in the lower limbs (94%, 17/18), abnormal gait (89%, 16/18), genu valgum (89%, 16/18), reduced subcutaneous fat (78%, 14/18), delayed puberty (73%, 8/11), muscle weakness (67%, 12/18), hearing loss (39%, 7/18), hepatosplenomegaly (39%, 7/18), exophthalmos or impaired vision or visual field defect (33%, 6/18), and anemia (33%, 7/18). Twenty‐five percent (4/16) of patients had short stature. Serum level of alkaline phosphatase was elevated in 41% (7/17) of patients whereas beta‐C‐terminal telopeptide was elevated in 91% of patients (10/11). Among 12 patients, the Z‐scores of two patients were greater than 2.5 at the femur neck and the Z‐scores of five patients were lower than −2.5 at the femur neck and/or lumbar spine. HR‐pQCT results showed lower volumetric BMD (vBMD), altered bone microstructure and lower estimated bone strength at the distal radius and tibia in patients with CED compared with controls. In addition, total volume bone mineral density and cortical volumetric bone mineral density at the radius were negatively correlated with age in patients with CED, but positively correlated with age in controls. In conclusion, the largest case series of CED with characterized clinical features in a Chinese population was reported here. In addition, HR‐pQCT was used to investigate bone microstructure at the distal radius and tibia in nine patients with CED, and the alteration of bone density, microstructure, and strength was shown for the first time. © 2021 American Society for Bone and Mineral Research (ASBMR). [ABSTRACT FROM AUTHOR]

Polyethyleneimine (PEI) has been extensively used as a common gene carrier due to its high gene transfection efficiency. PEI1.8k shows significantly lower cytotoxicity than its high molecular weight counterparts. However, it also has the problem of low gene transfection efficiency. To address the dilemma, a highly effective crosslinker (DTME) was synthesized to react with PEI1.8k to obtain CS-PEI1.8k. The reaction showed several advantages, such as a fast process in room temperature within nine hours with the product which can directly complex with DNA after removing the solvent. The ability of CS-PEI1.8k to agglomerate with DNA was proven by particle size, zeta potential, and gel retardation assays. The cytotoxic in vitro transfection ability and cell internalization capacity of CS-PEI1.8k were tested to verify the transfection capacity of CS-PEI1.8k. Moreover, we also studied the mechanism of the relatively high level of gene transfection by this binary complex compared with PEI25k. [ABSTRACT FROM AUTHOR]

With the increasing number of underground engineering construction projects such as coal mining, tunnel, and subway, water inrush disasters occur more and more frequently. Inspired by the phenomenon of microbial mineralization and diagenesis, microbial-induced calcium carbonate precipitation (MICP) is used to repair cracks in cement-based materials, which provides a new idea to solve the problem of water inrush. To investigate the self-healing properties of microbial capsules, this paper selected epoxy resin E-51 cured by DMP-30 as the wall material and Bacillus pasteurii as the core materials for experiments. In this paper, a single-factor method was adopted to determine the optimal preparation process of microbial capsules and the oil-phase separation method to prepare the microbial capsules. The effects of various factors on the experimental results under different core-wall ratios, reaction time, reaction temperatures, and agitation rates were analyzed. Microbial capsules were analyzed by Fourier transform infrared spectroscopy and optical microscopy to explore the functional groups and features of microbial capsules. The experimental results showed that the microbial capsules achieved the best performance with a core-to-wall ratio of 1 : 3, a reaction temperature of 50°C, a reaction time of 40 min, and a stirring rate of 300 rpm. Meanwhile, we determined the spore survival rate of microbial capsules and finally studied the waterproofness, storage stability, and rupture under the pressure of microbial capsules. We concluded that microbial capsules have high-efficiency and self-healing properties. [ABSTRACT FROM AUTHOR]

Artificial meat offers a potential solution to consumer demand for meat, given global environmental concerns, public health problems, sustainability, and animal welfare problems. Although artificial meat may supplement or even replace traditional meat, it is still a challenge to reproduce muscle tissue's hierarchical structure. This review focused on the research history of artificial meat, the current technological challenges and possible solutions, and analyzed consumer attitudes toward artificial meat. Key findings and conclusions : With the rapid development of tissue engineering and bioreactor engineering, the new technologies for cultured meat have been continuously developed and improved. Extrusion, shear cell, and spinning are the main techniques for plant-based meat and its market has been expanding. Consumer attitudes toward cultured and plant-based meat vary by demographics and across cultures. There are some problems still needed to be overcome, including technology barriers and sensory, nutritional, health, and safety challenges in further developing the alternative meat market. ● The artificial meat market is expanding rapidly to meet consumer demands. ● The technologies for artificial meat have been continuously developed and improved. ● The sensory, nutritional, health, and safety of artificial meat remain hurdles. ● Consumer attitude towards artificial meat varies across demographics and cultures. [ABSTRACT FROM AUTHOR]

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This paper aimed to explore the risk factors of peripherally inserted central catheter (PICC) related thrombosis (PICC-RT) in tumor patients mediated by ultrasound images under minimum variance (MV) algorithm and put forward the corresponding nursing intervention methods based on the risk factors. The smoothing algorithm, diagonal loading algorithm, and coherence factor algorithm were optimized via MV algorithm. The optimized algorithm was compared with other algorithms to analyze its image quality and image processing speed. Literature retrieval was conducted to analyze the risk factors of PICC-RT in tumor patients. Tumor patients who received PICC for chemotherapy in the hospital from June 2018 to December 2019 were selected. Patients who were accepted before the experiment were taken as the controls, and there were control group (89 cases) and observation group (91 cases). Exercise, average flow rate of axillary vein per unit time, and PICC-RT were compared between the two groups. The results showed that the optimized algorithm (MV-N) had better image resolution, image contrast, and calculation speed than other algorithms. Gender, body mass index (BMI), pathological type, clinical stage, disease history, fibrinogen (FIB), and use of anticoagulant drugs were risk factors for PICC-RT in tumor patients. The number of PICC-RT and complications in the observation group was notably lower in contrast to the control group (P < 0.05). It indicated that a novel algorithm was successfully established, which could increase the ultrasonic image quality and computing speed, and upper limb exercise could reduce the incidence of PICC-RT and its complications in tumor patients. [ABSTRACT FROM AUTHOR]

Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may persist in patients with coronavirus disease 2019 (COVID-19) despite receiving standard care. Methods: In this pilot study of hospitalized adult patients (≥18 years of age), with radiologically confirmed pneumonia who were SARS-CoV-2 positive for more than 28 days despite standard care, were assigned to receive standard of care (SOC, grp I) or leflunomide + SOC (grp 2). After 2 weeks, grp 1 and grp 2 patients who continued to be SARS-CoV-2-positive received leflunomide for 14 days while continuing SOC. The primary outcomes were the rate of and time to SARS-CoV-2 clearance and the 14-day and 30-day hospital discharge rate. Results: 12 patients were enrolled in grp 1 and 15 patients were in grp 2. The 14 days SARS-CoV-2 viral clearance rate was 80.0% (12/15) for grp 2 patients receiving leflunomide vs. 16.7% for grp 1 patients (2/12) (p = 0.002). By day 14, the median time to SARS-CoV-2 clearance was 6.0 days (range 1–12, IQR 1–12) for grp 2 patients. In grp 1, two patients converted to viral negative on days 1 and 6 (p = 0.002). The 14-day discharge rate was 73.3% (11/15) for the grp 2 vs. 8.3% (1/12) for grp 1 (p = 0.001). The 30 days discharge rate was 100% (15/15) for the grp 2 vs. 66.7% (8/12) for grp 1. No severe adverse events or deaths were reported. Conclusion: Leflunomide may improve the SARS-CoV-2 clearance rate and discharge rate in patients with refractory COVID-19. The tolerability of the 14–28 days course of treatment with leflunomide is acceptable. These preliminary observations need to be verified by a large sample size and randomized controlled trial. [ABSTRACT FROM AUTHOR]

In this study, 16 groups of tests were designed by the orthogonal test method, and a PU grouting material was prepared, which can be used for the construction of sealing wall in mined-out area of coal mine. The basic properties of the material were measured. Firstly, the viscosity of four groups of samples with different polyether polyol contents was measured by a dynamic rheometer. Secondly, the uniaxial compressive strength of pure slurry samples and sand-containing samples was measured by a universal testing machine. Finally, the failure process of sand-containing samples was monitored by acoustic emission equipment. Through the above research and analysis, a PU grouting material with excellent performance has been obtained. That is, when the ratio of polyether triol:polyether tetraol:catalyst:surfactant:chain extender:plasticizer is 11 : 9 : 0.5 : 1.0 : 1.2 : 6.0, PU grouting material has higher injectability and ideal compressive strength, which has been proved in grouting experiments. [ABSTRACT FROM AUTHOR]

In order to explore the law of groundwater evolution, the water source connection between faults and aquifers and the main sources of mine water inrush in the deep mining area of Yangcheng Coal Mine in Jining City, 40 groups of hydrochemical samples were collected and analyzed by Piper Diagram and Durov Diagram. The results showed that the fluidity of groundwater developing to the deep became weaker, the value of total dissolved solids (TDS) became larger. So, the roof and floor of coal seam were more similar in water quality types due to the conduction of faults. Using principal component analysis (PCA) to the raw data, two principal components were extracted, and the principal component scores were used as clustering variables for hierarchical cluster analysis (HCA), 5 groups of abnormal water samples were eliminated and 3 clustering groups M1, M2 and M3 were obtained from the other water samples on the tree diagram. The results showed that the combination of HCA and hydrochemical analysis was more effective in screening water samples, and the 3 clustering groups could be qualified samples to represent 3 major aquifers (Taiyuan Formation limestone aquifer, Shanxi Formation sandstone aquifer and Ordovician limestone aquifer). Finally, taking M1, M2 and M3 as grouping variables, the discriminant functions f 1 , f 2 and f 3 of the 3 aquifers were obtained, the results of stepwise discrimination analysis (SDA) showed that the discrimination model established by using 25 groups of standard water samples could discriminate the known water samples with the correct rate of 96%, 10 groups of unknown water samples collected at the fault are identified as Taiyuan Formation limestone water samples, which was consistent with the classification results of HCA, proving that the water inrush of fault DF53 was from Taiyuan Formation limestone aquifer, while the fault had little influence on Ordovician limestone aquifer. [ABSTRACT FROM AUTHOR]

Malnutrition in patients with gastric cancer (GC) with normal body mass index (BMI) is often ignored. This study aimed to explore the role of sarcopenia in predicting postoperative complication and long‐term survival in patients with GC with normal BMI. We included patients with normal BMI (18.5 kg/m2 ≤ BMI < 23 kg/m2) who underwent radical gastrectomy between July 2014 and December 2016. Sarcopenia was assessed by muscle mass, handgrip strength, and gait speed. Kaplan–Meier survival analysis was used to analyze the association between sarcopenia and the prognosis of patients with GC. Univariate and multivariate analyses were used to identify risk factors contributing to postoperative complications and long‐term survival. Overall, 267 patients with GC with normal BMI were included in this study; of which 49 (18.35%) patients were diagnosed with sarcopenia. Patients with sarcopenia had higher incidence of a major postoperative complication, longer postoperative hospital stays, and greater hospital costs. The Kaplan–Meier survival analysis showed that patients with sarcopenia had poorer overall survival than non‐sarcopenia patients. Univariate and multivariate analyses showed that sarcopenia was an independent predictor for postoperative complication and long‐term survival in such patients. Sarcopenia is an independent predictor for postoperative complications and long‐term survival in patients with normal BMI after radical gastrectomy for GC. We recommend that patients with normal BMI should perform nutritional risk screening by sarcopenia. [ABSTRACT FROM AUTHOR]

Background. Accurate delineation of tumor margin is essential for complete resection of early gastric cancer (EGC). The objective of this study is to assess the performance of magnifying endoscopy with narrow-band imaging (ME-NBI) for the accurate demarcation of EGC margins. Methods. We searched PubMed, EMBASE, Web of Science, and Cochrane Library databases up to March 2020 to identify eligible studies. The diagnostic accuracy of ME-NBI for EGC margins was calculated, and subgroup analyses were performed based on tumor size, depth of tumor invasion, tumor-occupied site, macroscopic type, histological type, Helicobacter pylori (H. pylori), and endoscopists' experience. Besides, we also evaluated the negative and positive resection rates of the horizontal margin (HM) of EGC after endoscopic submucosal dissection (ESD) and surgery. Results. Ten studies comprising 1018 lesions were eligible in the databases. The diagnostic accuracy of ME-NBI for the demarcation of EGC margins was 92.4% (95% confidence interval (CI): 86.7%-96.8%). According to ME-NBI subgroup analyses, the rate of accurate evaluation of EGC margins was not associated with H. pylori infection status, tumor size, depth of tumor invasion, tumor-occupied site, macroscopic type, histological type, and endoscopists' experience, and no statistical differences were found in subgroup analyses. Moreover, the negative and positive resection rates of HM after ESD and surgery were 97.4% (95% CI: 92.1%-100%) and 2.6% (95% CI: 0.02%-7.9%), respectively. Conclusions. ME-NBI enables a reliable delineation of the extent of EGC. [ABSTRACT FROM AUTHOR]

We proposed with excitement a novel molecular co-assembly (MCSA) that can effectively overcome the agglomeration of energetic materials. Through the coordinated self-assembly of polymethyl methacrylate-polyvinyl acetate (PMMA-PVA) with honeycomb-like structure and nanoparticles, a controlled and orderly distribution of nitroamine explosive (cyclotetramethylenetetranitramine, HMX; cyclotrimethylenetrinitramine, RDX; and hexanitrohexaazaisowurtzitane, CL-20) structure was achieved, above all, resolving the agglomeration problem availably. The modification ability of PMMA to RDX, HMX, and CL-20 at different temperatures was simulated by Materials Studio, which provided guidance for the ambient temperature of collaborative self-assembly. In order to compare the priority of the morphology and performance, RDX/PMMA-PVA, HMX/PMMA-PVA, and CL-20/PMMA-PVA composite particles with the same PMMA content were also fabricated by water suspension coating method, respectively. Structural characterizations and thermal stability of the composites were systematically studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), fourier-transform infrared (FT-IR) spectra, and differential scanning calorimeter (DSC). Moreover, the safety performance was analyzed by qualitative testing of impact sensitivity and friction sensitivity. The solid spherical PBX prepared via collaborative self-assembly all exhibited a perfect spherical structure, smooth, and flat coating, without any agglomeration. They had the same crystalline structure as the uncoated explosives, simultaneously demonstrating lower impact sensitivity and higher energy performance. The application of collaborative self-assembly technology has broken through the key technical bottleneck of the shell material being easy to form a separate phase in the desensitization coating of explosives, availably resolved the problems of particle exposure and low coverage during the coating, thus possessing vital significance for reference in the design and fabrication of PBXs with core-shell structure. [ABSTRACT FROM AUTHOR]

The photocatalysis of titanium dioxide (TiO2) exerts excellent degradation performance against contaminants in the environment. However, it prefers to absorb ultraviolet light rather than visible light, which significantly constrains its widespread use under visible light. Here, we prepared oxygen vacancy-containing TiO2via Ag-modification and N-doping. The utilization of visible light for phenol degradation was significantly enhanced by Ag/N co-doping. The characterization results showed a shuttle-like material coupled with multiple oxygen vacancies, and a well-designed experiment demonstrated that the Ti : N : Ag ratio of 1 : 0.45 : 0.32 presented optimal performance for phenol degradation. The batch experiment results also proved the modified TiO2 as a potent photocatalyst against phenol degradation with an 80.8% degradation efficiency within 5 hours under visible light and with a 99.3% degradation efficiency within 2 hours under ultraviolet light. What is more, we also demonstrated that hydroxyl radical was the mainly effective radical in the mineralization of phenol and put forward a possible degradation pathway based on the observed intermediates. Lastly, the cycling tests indicated that the proposed photocatalyst is durable with a fair phenol degradation ability after recycling 5 times. [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID‐19) poses a serious threat to human health and lives. The virus is still spreading throughout the world, and the cumulative number of confirmed cases is increasing. After patients with COVID‐19 are treated and discharged, some have repeated clinical symptoms and become positive for nucleic acid tests a second time. Through analysis and review of the existing literature, the proportion of repositive patients in the discharged patient population and their clinical characteristics were systematically described for the first time. Furthermore, an in‐depth analysis of the causes of repositive nucleic acid tests and the potential transmission of the disease provides the basis for the management and protection of discharged patients with COVID‐19. [ABSTRACT FROM AUTHOR]

Background: The objective of this study was to investigate the relationship between clinical characteristics, as well as dosimetric parameters, and the risk of treatment‐related lymphopenia in esophageal squamous cell carcinoma (ESCC) treated with definitive chemoradiotherapy (CRT). Materials and Methods: Clinical characteristics and dosimetric parameters were collected from 436 patients with ESCC who received definitive CRT from 2010 through 2017. Absolute lymphocyte counts (ALCs) were obtained before, during, and 1 month after CRT. Grade 4 (G4) lymphopenia was defined as ALC <0.2 × 109/L during CRT. Logistic regression analysis was used to evaluate the effect of each factor on predicting G4 lymphopenia. The relationship between lymphopenia and overall survival (OS) was examined, and a nomogram was developed to predict OS. Results: G4 lymphopenia was observed in 103 patients (23.6%) during CRT. Multivariate analysis indicated that planning target volume (PTV), lung V10, heart V10, performance status, and pretreatment lymphopenia were significant risk factors for G4 lymphopenia. Patients with G4 lymphopenia had significantly worse survival than those without. Based on multivariate analysis, clinical TNM stage, radiotherapy modality, pretreatment ALC, and G4 lymphopenia were predictive of OS and were incorporated into the nomogram, yielding a concordance index of 0.71. Conclusions: G4 lymphopenia during definitive CRT was associated with larger PTVs, higher lung V10 and heart V10, and worse survival. Implications for Practice: The purpose of this study was to investigate the relationship between clinical characteristics, as well as dosimetric parameters, and the risk of treatment‐related lymphopenia in 436 patients with esophageal squamous cell carcinoma who received definitive chemoradiotherapy. Grade 4 (G4) lymphopenia was observed in 23.6% of patients during radiotherapy. G4 lymphopenia was associated with larger planning target volumes, higher lung V10 and heart V10, and worse survival. Then, a nomogram was built based on multivariate analysis, yielding excellent performance to predict overall survival. Prospective studies are needed to investigate potential approaches for mitigating severe lymphopenia, which may ultimately convert into survival benefits. This study explored the relationship between clinical characteristics, as well as dose‐volume histogram parameters, and the risk of treatment‐related lymphopenia in patients with esophageal squamous cell carcinoma treated with definitive chemoradiotherapy. This article evaluates whether lymphopenia is associated with patient outcomes and describes a nomogram built to predict survival. [ABSTRACT FROM AUTHOR]

Goaf sealing wall is set in the roadway close to the stop line of working face in an underground coal mine. However, the sealing wall is prone to crack or fracture under serious mining stress, resulting in water and air leakage from goaf. In this study, the combination of polymethylene polyphenyl polyisocyanate (PAPI) and methylene diphenyl diisocyanate (MDI) as component A and polyether polyols, catalysts, surfactants, chain extenders, and plasticizers as component B were investigated to optimize the exothermic, foaming, and mechanical properties of modified polyurethane (PU) as the filling material for goaf sealing wall. Firstly, the reaction temperature of specimens with different contents of polyether polyols was monitored using a dynamic acquisition system; secondly, the effect of polyether polyols, catalysts, and surfactants on foaming property was studied; then, uniaxial compression tests were developed to obtain compressive behavior; finally, the microstructure after uniaxial compression was observed by using a scanning electron microscope (SEM). The results indicate that the pure chemical slurry is superior to the combination of chemical slurry and sand in compressive strength and deformation behavior. The optimal mass ratio of polyether triols, polyether tetraols, catalysts, surfactants, chain extenders, and plasticizers is 11 : 9 : 1.0 : 0.5 : 1.2: 6 in component B due to the maximum reaction temperature of 121.4°C, the expansion ratio of 2.6, and the compressive strength of 7.97 MPa at the strain of 10% in this study. The research provides a solution for the construction of the sealing wall, which is of great significance to safety production in an underground coal mine. [ABSTRACT FROM AUTHOR]

Background/Aims: The aim of this study was to develop a tool to predict multidrug-resistant bacteria infections among patients with biliary tract infection for targeted therapy. Patients and Methods: We conducted a single-center retrospective descriptive study from January 2016 to December 2018. Univariate and multivariable logistic regression analysis were used to identify independent risk factors of multidrug-resistant bacterial infections. A nomogram was constructed according to multivariable regression model. Moreover, the clinical usefulness of the nomogram was estimated by decision curve analysis. Results: 121 inpatients were randomly divided into a training cohort (n = 79) and validation cohort (n = 42). In multivariate analysis, 5 factors were associated with biliary tract infections caused by multidrug-resistant bacterial infections: aspartate aminotransferase (Odds ratio (OR), 13.771; 95% confidence interval (CI), 3.747-64.958; P < 0.001), previous antibiotic use within 90 days (OR, 4.130; 95% CI, 1.192-16.471; P = 0.032), absolute neutrophil count (OR, 3.491; 95% CI, 1.066-12.851; P = 0.046), previous biliary surgery (OR, 3.303; 95% CI, 0.910-13.614; P = 0.079), and hemoglobin (OR, 0.146; 95% CI, 0.030-0.576; P = 0.009). The nomogram model was constructed based on these variables, and showed good calibration and discrimination in the training set [area under the curve (AUC), 0.86] and in the validation set (AUC, 0.799). The decision curve analysis demonstrated the clinical usefulness of our nomogram. Using the nomogram score, high risk and low risk patients with multidrug-resistant bacterial infection could be differentiated. Conclusions: This simple bedside prediction tool to predict multidrug-resistant bacterial infection can help clinicians identify low versus high risk patients as well as choose appropriate, timely initial empirical antibiotics therapy. This model should be validated before it is widely applied in clinical settings. we can differentiate between [ABSTRACT FROM AUTHOR]

Introduction: Gene expression association studies of tumor samples have uncovered several long non-coding RNAs (lncRNAs) closely related to various types of cancer. Several lncRNAs have been reported to play essential roles in the progression of papillary thyroid carcinoma (PTC). Novel lncRNA inhibiting proliferation and metastasis (lnc-NLIPMT) is a known regulator of mammary cell proliferation and motility, but its involvement in PTC is unclear. Materials and Methods: We investigated the role of lnc-NLIPMT in PTC by quantitative real-time polymerase chain reaction (qRT-PCR) on various PTC tissue samples and cell lines. We assessed the effects of overexpression or knockdown of lnc-NLIPMT on the proliferation, migration, and invasion of PTC cells using CCK-8, cell clone formation, and transwell assays. Changes in the expression of N-cadherin and vimentin were detected by immunoblotting. Results: Our results revealed a downregulation of the expression of lnc-NLIPMT in PTC and a negative correlation between lnc-NLIPMT expression and tumor size (P=0.006). Overexpression of lnc-NLIPMT in TPC-1 and B-CPAP cells significantly suppressed cell proliferation, migration, and invasion, while lnc-NLIPMT knockdown had the opposite effect. In addition, lnc-NLIPMT played an important role in the regulation of the expression of N-cadherin and vimentin. Conclusion: lnc-NLIPMT inhibits cell proliferation and metastasis of PTC cells and is a potential diagnostic and prognostic biomarker in PTC. [ABSTRACT FROM AUTHOR]

Background: With the effective prevention and control of COVID‐19 in China, the number of cured cases has increased significantly. Further monitoring of the disease prognosis and effective control of the "relapse" of the epidemic has become the next focus of work. This study analysed the clinical prognosis of discharged COVID‐19 patients by monitoring their SAR‐CoV‐2 nucleic acid status, which provided a theoretical basis for medical institutions to formulate discharge standards and follow‐up management for COVID‐19 patients. Methods: We included 13 discharged COVID‐19 patients who were quarantined for 4 weeks at home. The patient's daily clinical signs were recorded and sputum and faecal specimens were regularly sent for detection of SARS‐CoV‐2 nucleic acid. Results: The time between initial symptoms and meeting discharge criteria was 18 to 44 days with an average of 25 ± 6 days. The faecal samples of two patients still tested positive after meeting the discharge criteria and the sputum samples of four patients returned positive 5 to 14 days after discharge. The rate of the recurring positive test result in samples from the respiratory system was 31% (4/13). Conclusion: Under the present discharge criteria, the high presence of SARS‐CoV‐2 nucleic acid in faecal and respiratory samples of discharged COVID‐19 patients indicates potential infectivity. Therefore, we suggest that faecal virus nucleic acid should be tested as a routine monitoring index for COVID‐19 and a negative result be added to the criteria. Simultaneously, we should strengthen the regular follow‐up of discharged patients with continuous monitoring of the recurrence of viral nucleic acid. Highlights: The positive rate of SARS‐CoV‐2 nucleic acid in faeces and respiratory tract of discharged COVID‐19 patients both were high, which indicate potential infectivity. [ABSTRACT FROM AUTHOR]

Acrylamide (ACR) is a common chemical used in various industries and it said to have chronic neurotoxic effects. It is produced during tobacco smoking and is also generated in high-starch foods during heat processing. Notoginsenoside R1 (NR1) is a traditional Chinese medicine, which is used to improve the blood circulation and clotting. The objective of this study was to investigate the mechanism of ACR-triggered neurotoxicity and to identify the protective role of NR1 by upregulating thioredoxin-1 (Trx-1). Our results have shown that NR1 could block the spatial and cognitive impairment caused by ACR administration. Bioinformatics analysis revealed that Trx-1 regulated autophagy via Integrin alpha V (ITGAV). NR1 could resist the ACR-induced neurotoxicity by upregulating thioredoxin-1 in PC12 cells and mice. The autophagy-related proteins like autophagy-related gene (ATG) 4B, Cathepsin D, LC3 II, lysosomal-associated membrane protein 2a (LAMP2a), and ITGAV were restored to normal levels by NR1 treatment in both PC12 cells and mice. Besides, we also found that overexpression of Trx-1 resisted ACR-induced autophagy in PC12 cells and downregulation of Trx-1 triggered autophagy induced by ACR in PC12 cells. Therefore, it could be concluded that Trx-1 was involved in the autophagy pathway. Besides, we also found that ITGAV was an intermediate node linking Trx-1 and the autophagy pathway. [ABSTRACT FROM AUTHOR]

Respirable coal dust accounts for heart and respiratory diseases of coal miners such as asthma, pneumoconiosis, and black lung disease. What is more, coal dust explosion seriously affects coal mine safety production and coal miners' life safety. Generally, dust suppressants are commonly applied in coal mines. However, current dust suppressants are not working effectively. To develop a better dust suppressant, we attempt to explore the factors affecting the wettability of coal dust under different metamorphic levels from the essence of coal dust wetting mechanism in this paper. Specifically, we use Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) to reveal the microstructure of coal from two aspects of functional group and carbon skeleton structure and obtain the micro information of the surface functional group types, quantity, and carbon structure of coal with different degrees of metamorphism, as well as the change rule of functional group of coal sample with coal rank and the law of carbon increase and deoxidization of coal metamorphism. After that, we acquired the structural parameters of coal by the NMR experiments and fitted the quantitative mathematical relationship between the microstructure parameters and wettability of coal through SPSS and ORIGIN software. Finally, this paper constructs an evaluation model for the influencing factors of coal dust wettability, explains the influence degree of different coal dust structure on coal dust wettability, improves the coal dust wettability mechanism, and provides more quantitative research ideas and methods for the control of coal dust. [ABSTRACT FROM AUTHOR]

Microbial Induced Calcite Precipitation (MICP) is a biochemical process widely found in nature, also known as microbial mineralization. This paper investigates whether this process can help promote the intelligent reinforcement and repair of underground projects such as mines and tunnels. We selected Bacillus sphaericus and Bacillus mucilaginosus as the research objects. The former has an outstanding urease production ability, and the latter can secrete carbonic anhydrase in vitro. Bacillus mucilaginosus was introduced into the culture solution of Bacillus sphaericus in the most suitable culture environment, and the changes of mineralization rate and mineralization yield of Bacillus sphaericus were observed and analyzed. The results revealed that, to maintain the highest growth rate of Bacillus sphaericus, the optimal pH value was between 7 and 8, the optimal urea concentration was 0.5 mol/L, the optimal Ca2+ concentration was 0.6 mol/L, and the optimal Luria-Bertani (LB) culture concentration was 20 g/L. The amount of biomineralized calcium carbonate precipitated in the double bacteria solution can reach 1.89 times the amount of the precipitation in the Bacillus sphaericus solution under the same conditions. It concludes that the introduction of Bacillus mucilaginosus can effectively increase the mineralization yield of Bacillus sphaericus without affecting the mineralized products. [ABSTRACT FROM AUTHOR]

Gastric cancer (GC) patients with metastasis had limited treatment options and dismal outcome. We have previously reported the aberrant expression of Zic family member 1 (Zic1) in GC. However, the functional roles and underlying mechanism of Zic1 in GC metastasis remain unknown. Here, we demonstrate that lower expression of Zic1 was correlated with more lymph node metastasis and poor outcome of GC patients. Ectopic expression of Zic1 suppressed both lung metastasis and peritoneal tumor dissemination of GC in mice. The metastatic suppressing ability of Zic1 was mediated by regulating the process of cell invasion, adhesion and epithelial‐mesenchymal transition (EMT). Mechanistically, Zic1 could downregulate Wnt targets including c‐Myc and Cyclin D1 by inhibiting LEF transcriptional activity in GC cells. Notably, Zic1 was inversely related to the expression of Cyclin D1 in GC tissues tested. In addition, Zic1 could physically interact with β‐catenin/transcription factor 4 (TCF4) and disrupt their complex formation, while not affecting β‐catenin nuclear localization. Collectively, our study indicated that Zic1 suppressed GC metastasis through attenuating Wnt/β‐catenin signaling and the EMT process. Our work may provide novel therapeutic strategies for the metastasis of GC. [ABSTRACT FROM AUTHOR]

Cycloaddition reactions such as intramolecular Diels–Alder (IMDA) are extremely important in constructing multicyclic scaffolds with diverse bioactivities. Using MycB as a biomarker, three new polyketides – Chaetolivacines A (1), B (3), and C (4) – with one known compound Myceliothermophin E (2) comprising of decalin and 4-hydroxy-2-pyridones were obtained from the culture of Chaetomium olivaceum SD-80A under the guidance of gene mining. The structures of these compounds were established using detailed 1D, 2D NMR, and high-resolution electron spray ionization mass spectroscopy (HRESIMS) analysis. The relative and absolute configurations of the compounds 1 , 3 , and 4 were elucidated by NOESY and ECD. The biosynthesis pathways of these compounds were proposed, which involves in three key genes ChaA [polyketide synthase-non-ribosomal peptide synthetases (PKS-NRPS)], ChaB , and ChaC. Compounds 1 – 4 were tested for their antimicrobial activities, and compounds 2 and 3 showed moderate bioactivity against Staphylococcus aureus (SA) and methicillin-resistant S. aureus (MRSA) with MIC values of 15.8 and 27.1 μM. The results showed that configuration of C-21 in 3 and 4 is important for anti-SA and anti-MRSA activities. This study reveals the significant potential of the genus Chaetomium in producing new PKS-NRPS, therefore increasing the speed in the mining for new sources of antimicrobial agents. [ABSTRACT FROM AUTHOR]

A series of quinazoline derivatives with benzylidene hydrazine carboxamide were designed and synthesised as EGFR inhibitors. Most compounds exhibited exceptional anti-proliferative activity against A549, HepG2, MCF-7 and H1975 cells. Furthermore, six compounds demonstrated excellent inhibition activity against EGFRWT with the IC50 value both less than 2 nM. Among the six compounds, 44 exhibited the strongest activity (0.4 nM) and potently inhibited EGFRL858R/T790M (0.1 μM). Excitingly, the most potent compound 14 showed excellent enzyme inhibitory activity with 6.3 nM and 8.4 nM for both EGFRWT and EGFRT790M/L858R. The result of AO single staining and Annexin V/PI staining showed that the compound 14 and 44 could induce remarkable apoptosis of A549 cells. The compound 14 arrested the cell cycle at the S phase and compound 44 arrested the cell cycle at the G0 phase in A549 cells. These preliminary results demonstrate that compound 14 and 44 may be promising lead compound-targeting EGFR. [ABSTRACT FROM AUTHOR]

To study two-phase flows occurring in the process of coaxially electrospinning core-shell composite nanofibers, a mathematic physical model was proposed with shear-thinning fluid properties, surface tension, and electric fields specially considered. Numerical results showed three flow patterns: slug, slug-annular transitional, and annular flows. According to a flow pattern model based on the Weber number, slug-annular transitional flows were predicted to occur when the Weber number was between 0.5 and 26, whereas the slug and annular flows were to be expected when the Weber number was less than 0.5 and greater than 26, respectively. Body forces (induced by electric fields) and surface tension forces had more explicit effects on the flow patterns than forces due to viscosity and permeability gradients on interfaces. To form an annular flow pattern with smooth core-shell interfaces, which is favored in engineering practice, the applied electric field should be stronger than 100 kv/m. [ABSTRACT FROM AUTHOR]

This article is part of the Topical Collection on Image of the month A 5-year-old boy with left parapharyngeal space mass was scheduled to a PET/CT examination for disease diagnosis. Overall, this case proposed a method using LAFOV PET/CT to salvage an examination which would otherwise have been lost due to involuntary movement of a child without sedation and avoided extra dose to the patient. [Extracted from the article]

Goals: The development of new treatment for drug abuse requires identification of targetable molecular mechanisms. The pathology of glutamate neurotransmission system in the brain reward circuit is related to the relapse of multiple drugs. Glutamate transporter regulates glutamate signaling by removing excess glutamate from the synapse. And the mechanisms between glutamate transporter and drug addiction are still unclear. Methods: A systematic review of the literature searched in Pubmed and reporting drug addiction in relation to glutamate transporter. Studies were screened by title, abstract, and full text. Results: This review is to highlight the effects of drug addiction on glutamate transporter and glutamate uptake, and targeting glutamate transporter as an addictive drug addiction treatment. We focus on the roles of glutamate transporter in different brain regions in drug addiction. More importantly, we suggest the functional roles of glutamate transporter may prove beneficial in the treatment of drug addiction. Conclusion: Overall, understanding how glutamate transporter impacts central nervous system may provide a new insight for treatment of drug addiction. [ABSTRACT FROM AUTHOR]

The effects of partially replacing NaCl with sodium substitutes (SS) on the lipid and protein oxidation and flavor development of Harbin dry sausage was investigated. There were three salt formulations, including a control (100% NaCl), NaCl partially substituted with KCl (SS1) (70% NaCl and 30% KCl), and NaCl partially substituted with KCl combined with other components (SS2) (70% NaCl, 20% KCl, 4% lysine, 1% alanine, 0.5% citric acid, 1% Ca-lactate and 3.5% maltodextrin). The levels of lipid and protein oxidation increased in all sausages during fermentation (P < 0.05). In addition, lower oxidation of lipids and proteins were found in the SS2 treatment (P < 0.05) due to the lower NaCl concentration. The SS, especially the SS2, promoted the formation of volatile compounds originated from carbohydrate and amino acid metabolism, β-lipid oxidation and esterification; however, this substitute inhibited the formation of volatile compounds originated from lipid autooxidation (P < 0.05). Overall, SS2 could improve the flavor development of Harbin dry sausage and reduce NaCl by 30%. • Sausage with sodium substitute SS2 had a higher water activity and a lower pH. • Sodium substitute (SS) reduced the lipid and protein oxidation in dry sausages. • SS promoted the formation of 3-hydroxy-2-butanone, 1-octen-3-ol and ethyl acetate. • SS reduced 30% NaCl and improved the flavor in Harbin dry sausage. [ABSTRACT FROM AUTHOR]

The effect of partial replacement of NaCl by using sodium substitutes (SS) on the physical, microbial and sensory characteristics of Harbin dry sausage was investigated. There were three salt formulations, including control (100% NaCl), NaCl partly substituted by KCl (SS1) (70% NaCl and 30% KCl), and NaCl partly substituted by KCl combined with other components (SS2) (70% NaCl, 20% KCl, 3.5% maltodextrin, 4% L-Lys, 1% L-Ala, 0.5% citric acid and 1% Ca-lactate). After a 12-day fermentation, the higher moisture content and Aw and lower pH were found in the SS2 treatment, compared to the control and SS1 treatments (P <.05). A decreased microbial diversity during fermentation was found in all sausages, and Staphylococcus spp. and Lactobacillus spp. became the dominant genera. Additionally, the SS2 treatment showed a higher L *-value and lower hardness and chewiness values (P <.05). Therefore, the formulation of SS2 could achieve a NaCl reduction of 30% in Harbin dry sausages with a better sensory acceptability. • Sausages with sodium substitutes had higher moisture content and water activity. • Lactobacillus and Staphylococcus became the dominant bacteria in the sausages. • Sodium substitute SS2 could replace 30% NaCl in Harbin dry sausage. [ABSTRACT FROM AUTHOR]

This study investigated the purification and biochemical characteristics of the protease produced by Pediococcus pentosaceus isolated from Harbin dry sausages. The optimized fermented conditions were as follows: fermentation time 36 h, initial pH 5 and fermentation temperature 30 °C. A 29.6 kDa extracellular protease was purified using ammonium sulphate deposition, ion exchange layer system and gel filtration. The protease produced by P. pentosaceus had a certain pH and thermal stability at pH 6 and 30 °C. The microbial protease activity could be inhibited by ethylene diamine tetraacetic acid disodium salt (EDTA). V max and K m of the protease were 43.9 mg/min and 8.3 mg/mL, respectively. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) reflected the ability of the protease to hydrolyse sarcoplasmic and myofibrillar proteins, particularly those of myosin heavy chain, paramyosin, actin, phosphorylase and creatine kinase-M types. 3D structure modelling of the P. pentosaceus protease found two domains in the protease protein and the correlation of the active sites with protease properties and substrate specificity. In conclusion, P. pentosaceus can be used as a starter culture or enzyme producing strain for inoculation in Harbin dry sausages. • Fermentation conditions were optimized for the protease production from strain. • Enzymatic properties of the purified protease were investigated. • P. pentosaceus protease can hydrolyse myofibrillar and sarcoplasmic protein. • P. pentosaceus protease structures were simulated by homology modelling. [ABSTRACT FROM AUTHOR]

To explore a new algorithm and strategy for rhythm analysis during chest compressions (CCs), and to improve the efficiency of cardiopulmonary resuscitation (CPR) by minimizing interruptions. The clinical data and ECG of patients with sudden cardiac arrest (CA) from three hospitals in China were collected with Philips MRx monitor/defibrillators. The length of each analyzed ECG segment was 23 s, the first 11.5 s was selected to contain CPR compressions, the next 5 s had no compressions, and the last 6.5 s had no requirement. Three experienced emergency doctors annotated the ECG segments without compression artifacts. A two-step analysis through CPR (ATC) algorithm was applied to the selected data. The first step was analysis during chest compressions. If a shockable rhythm was not detected, compression-free analysis followed. The results of the ATC algorithm were compared with the annotations by the physicians, to determine the sensitivity and specificity of the algorithm. In total 166 CA patients were included with 100 out-of-hospital cardiac arrest (OHCA) patients and 66 in-hospital cardiac arrest (IHCA) patients. A total of 1578 ECG segments were analyzed, including 115 (7.3%) shockable rhythms, 1278 (81.0%) non-shockable rhythms, and 185 (11.7%) intermediate/unknown rhythms. The specificity of all non-shockable rhythms was 99.8% at the end of chest compressions, and 99.5% after analysis without compression artifact. 70.5% of ventricular fibrillation (VF) rhythms were detected by the end of chest compressions. After the CC-free analysis, 93.6% of VF was identified. The ATC algorithm achieved sensitivity of 93.6% and specificity of 99.5% after the two-step analysis, and 70.5% of the patients with shockable rhythms did not require CC-free analysis. Such an approach has the potential to substantially reduce CC interruptions when identifying shockable rhythms. [ABSTRACT FROM AUTHOR]