Search

Jichan Shi,1,* Gexin Gao,2,* Zhijie Yu,3,* Kaihuai Wu,4 Youquan Huang,5 Lian-Peng Wu,6 Zhengxing Wu,1 Xinchun Ye,1 Chaochao Qiu,1 Xiangao Jiang1 1Department of Infectious Disease, Wenzhou Central Hospital, The Dingli Clinical Institute of Wenzhou Medical University, Wenzhou, Zhejiang, 325000, People’s Republic of China; 2Department of Nursing School, Wenzhou Medical University, Wenzhou, Zhejiang, 325000, People’s Republic of China; 3Department of Hematology, Wenzhou Key Laboratory of Hematology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, People’s Republic of China; 4Departments of Infectious Diseases, Taishun People’s Hospital, Wenzhou, 325000, People’s Republic of China; 5Departments of Infectious Diseases, Yongjia People’s Hospital, Wenzhou, 325000, People’s Republic of China; 6Department of Laboratory, Wenzhou Central Hospital, The Dingli Clinical Institute of Wenzhou Medical University, Wenzhou, Zhejiang, 325000, People’s Republic of China*These authors contributed equally to this workCorrespondence: Xiangao Jiang, Department of Infectious Disease of Wenzhou Central Hospital, The Dingli Clinical Institute of Wenzhou Medical University, 252 Baili East Road, Lucheng District, Wenzhou, Zhejiang, 325000, People’s Republic of China, Tel +86 13587691822, Fax +86 577 88070007, Email jiang_xiangao@126.comBackground: Tuberculosis (TB) is still the single pathogen infectious disease with the largest number of deaths worldwide. The relationship that intestinal microbiota disorder and de novo fatty acid synthesis metabolism have with disease progression in multi-drug resistant TB (MDR-TB) has not yet been fully studied.Objective: To investigate the effects of long periods of MDR-TB, pre-extensively drug-resistant TB (pre-XDR-TB), or rifampicin-resistant TB (RR-TB) on gut microbiome dysbiosis and advanced disease.Methods: The sample was chosen between March 2019 and September 2019 in Wenzhou Central Hospital and comprised 11 patients with pre-XDR-TB, 23 patients with RR-TB, and 28 patients with MDR-TB. Healthy individuals were chosen as the control group (CK group). An overnight fast blood sample was drawn via venipuncture into tubes without anticoagulant. For analysis, 300 mg of faeces from patients from the same group was mixed and analysed using DNA extraction, NGS sequencing, and bioinformatics. A QIAamp Fecal DNA Mini Kit was used to isolate the DNA. The extracted DNA was stored at − 20°C.Results: Advanced TB was concurrent with an elevated level of the proportions of acetyl-CoA carboxylase (ACC1) to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and fatty acid synthase (FASN) to GAPDH in de novo fatty acids synthesis, and Eubacterium, Faecalibacterium, Roseburia, and Ruminococcus were increased significantly in RR-TB patients compared to healthy individuals, whereas their abundance in the pre-XDR-TB and MDR-TB groups showed little change in comparison with the control group. Proteobacteria levels were greatly increased in the RR-TB and MDR-TB patient groups but not in the patients with pre-XDR-TB or the healthy subjects. The pre-XDR-TB group exhibited alterations of the intestinal microbiome: coliform flora showed the highest abundance of Verrucomicrobiales, Enterobacteriales, Bifidobacteriales and Lactobacillales. De novo fatty acids synthesis was enhanced in patients and was associated with the gut microbiome dysbiosis induced by the antimicrobials, with Bacteroidetes, Bacteroidales, and Bacteroidaceae displaying the most important correlations on a phylum, order, and family level, respectively.Conclusion: The progression to advanced TB was observed to be a result of the interaction between multiple interrelated pathways, with gut–lung crosstalk potentially playing a role in patients with drug-resistant TB.Keywords: multi-drug resistant TB disease, gut commensal, microbial imbalance, de novo fatty acids synthesis, microbiome biosignature alterations

Groundwater serving as a drinking water resource usually contains manganese ions (Mn2+) that exceed drinking standards. Based on the Mn biogeochemical cycle at the hydrosphere scale, bioprocesses consisting of aeration, biofiltration, and disinfection are well known as a cost-effective and environmentally friendly ecotechnology for removing Mn2+. The design of aeration and biofiltration units, which are critical components, is significantly influenced by coexisting iron and ammonia in groundwater; however, there is no unified standard for optimizing bioprocess operation. In addition to the groundwater purification, it was also found that manganese-oxidizing bacteria (MnOB)-derived biogenic Mn oxides (bioMnOx), a by-product, have a low crystallinity and a relatively high specific surface area; the MnOB supplied with Mn2+ can be developed for contaminated water remediation. As a result, according to previous studies, this paper summarized and provided operational suggestions for the removal of Mn2+ from groundwater. This review also anticipated challenges and future concerns, as well as opportunities for bioMnOx applications. These could improve our understanding of the MnOB group and its practical applications.

To evaluate the value of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) in the detection of drug resistance of Mycobacterium tuberculosis in re-treated patients.MALDI-TOF MS was used to detect the resistance of 202 cases of retreatment pulmonary tuberculosis infection strains to isoniazid (INH), rifampin (RFP), ethambutol (EMB), streptomycin (SM), ofloxacin (Ofx), moxifloxacin (Mfx), amikacin (Am), Kanamycin (Km) and capreomycin (Cm), and the results were compared with those of BACTEC 960 liquid culture detection to compare the coincidence rate of the two methods.MALDI-TOF MS detected 60 copies of Mtb gene mutation, and drug-resistant gene mutation strains accounted for 34.68% (60/173) of positive strains. Rifampicin-related rpoB gene mutations accounted for 86.67% (52/60), isoniazid-related katG + inhA gene mutations accounted for 80.00% (48/60) and inhA-15 gene mutations accounted for 8.33% (5/60), streptomycin-related rpsL gene mutations accounted for 28.33% (17/60), ethambutol-related embB gene mutations accounted for 45.00% (27/60), quinolone-related gyrA basic mutation accounted for 26.67% (16/60), ethyl/propylthiamine-related embB gene mutation accounted for 36.67% (22/60) and inhA-15 gene mutation accounted for 10.00% (6/60), aminoglycoside-related rrs gene mutation accounted for 26.67% (16/60), clofazimine Fazimine, bedaquiline related Rv0678 193 gene mutations accounted for 3.33% (2/60), pyrazinamide, p-aminosalicylate, linezolid were not seen mutated genes. Multi-gene mutant strains accounted for 63.33% (38/60) of drug-resistant strains.MALDI-TOF MS assay has good agreement with BACTEC960 liquid culture drug sensitivity test, which can be a rapid and effective method to screen for drug resistance of Mycobacterium tuberculosis, and has some clinical application value in patients with relapse tuberculosis.

Structural health monitoring (SHM) of the ball screw of machine tools relies on the repeated observation of the damage-sensitive features. The natural frequency is a characteristic inherent to the structure that is more robust than other signal features as a SHM index. However, a major problem is that regular changes in the operating conditions, such as the feed speeds, the worktable positions and other uncertain complex boundary conditions, also affect the natural frequencies, and these factors may mask the subtle variations induced by structural damage. Therefore, it is necessary to adopt an effective method to eliminate those effects to avoid false alarms during structural damage monitoring. In this article, Bayesian ridge regression modelling methods are developed to eliminate the effects of the worktable different positions and feed speeds on the natural frequencies. The proposed method can model the natural frequencies that are simultaneously affected by two dimensional operational factors and provide a rigorous quantitative assessment of the uncertainties associated with the complex boundary conditions of the ball screw drive system and the inevitable estimation errors. First, the different worktable positions and feed speeds were tested on the experimental bench to verify the proposed method. Then, two novel criteria were used as damage warning signals, which can reduce false alarm. Finally, this method was applied to monitor the wear of a ball screw of a CNC machining centre in an automobile factory. The validity of the method was provend using actual monitoring results.

In this paper, we mainly study the pose estimation based on feature matching and manipulator grasping control. Obtaining the pose information of the object is an important part of autonomous grasp of the manipulator. In order to obtain the precise pose information of the object, an improved algorithm is proposed based on the GMS (Grid-Based Motion Statistics) algorithm. Firstly, we use the RANSAC algorithm to remove the point pairs whose the distance error is more than 1.5 pixels after transformation. Secondly, the Euclidean distance of the coefficients is calculated between original image and object image. Some point pairs with a larger distance are removed because of the affine invariant principle. The correct correspondences are transformed from 2D pixel coordinate frame to 3D camera coordinate frame with depth image. The least square method combined with SVD algorithm is used to solve the rotation and translation matrices of the object relative to the camera coordinate frame. These matrices are used to estimate the pose of the object. The high accuracy of feature matching in the improved GMS algorithm is verified. The estimated error of the position $(x, y, z)^{T}$ is within ±2.4mm, and the orientation $(\text{Roll}, \text{Pitch}, \text{Yaw})^{T}$ is within ±1°. Finally, the performance of the algorithm is verified through the grasping experiments with the manipulator.

Carbide-derived carbons (CDC) represent a kind of typical and fascinating porous carbon materials (PCM) for broad applications but demand hazardous chlorine to fulfil the conversion into carbon. Here in this study, we report the facile fabrication of PCM with rich porosity from mild molten alkaline-treated calcium carbide (CaC2). Resulted PCM under optimized synthesis conditions exhibited large specific surface area (∼839 m2 g−1) and specific capacitance (403 F g−1 at current density of 0.5 A g−1). Meanwhile, fairly good rate capability of retaining over 63% capacitance at large current density of 5 A g−1, and robust cycling performance (∼5% fading after 5000 cycles at high rate of 5 A g−1) can be also obtainable. Our study rendered a simple but effective method to utilize CaC2 as carbon source and may have broad applications such as adsorbents, anode materials for Li/Na-ion batteries.

The change of machine tool structure will cause variation in the dynamic characteristics of the tool, which will result in changes to the stability of the tool and poor machining quality. Some researchers have studied that the dynamics of the MTS are expected to change with the slight change of position and speed of MTS. However, there is almost no effective way to estimate modal parameters, as existing methods of estimating the modal parameters of MTS based on computer-aided engineering and experimental modal analysis can not extend to different combinations of positions and speeds. Simultaneously, the vibration signals of different measurement points on the MTS under different combinations of positions and speeds are isolated each other and data access are too inconvenient, leading to an inefficient and time-consuming work. Furthermore, it is difficult to visually characterize high-dimensional position- and speed-dependent dynamics of machine tool structure. To overcome these issues, it is the first time that we propose to construct the dynamics of machine tool structure knowledge graph (DMTSKG) to associate entire data under different combinations of positions and speeds to visually characterize and predict high-dimensional dynamic characteristics. The analysis results show the effectiveness and performance of our proposed method.

The tool tip frequency response function (FRF), as one of the essential inputs to calculate the stability lobe diagram (SLD), varies with the position and speed of changes in the moving components within the machine tool work volume. How to predict the position- and speed-dependent tool tip dynamics accurately has become one of the most challenging tasks in obtaining SLDs while avoiding chatter. However, traditional finite element analyses or kinematic modelling-based methods are costly and time consuming. Data-driven machine learning methods require large amounts of labeled data to train a model, but labeled industrial data are limited and extremely valuable in real manufacturing industries. To minimize experimentation, an improved semi-supervised graph convolutional network (GCN) is proposed to predict position- and speed- dependent tool tip dynamics with limited labeled data. First, the inverse stability solution is applied to identify dominant modal parameters under cutting conditions to obtain labeled samples. Subsequently, both the limited labeled samples and large amounts of unlabeled samples are converted into graph data to train a GCN regression model integrated with a multilayer perceptron. To avoid overfitting under limited data conditions, the conventional GCN is extended by stacking a transposed GCN, which is utilized to reconstruct the initial node features. The results demonstrate an improved prediction performance by adding the unsupervised reconstruction error into the loss function. Compared with other machine learning methods, our proposed method has superior performance in predicting tool tip dynamics with only 20% of the labeled samples. Finally, the SLDs were reconstructed with predicted FRFs, and the accuracy of the SLDs was validated through chatter tests.

Improving specific energy of supercapacitors (SCs) at high power has been intensively investigated as a hot and challengeable topic. In this work, hierarchically porous carbon (HPC) materials with well-defined meso-/macro-pores are reported via the dehalogenation reaction of polyvinyl fluoride (PVDF) by NaNH2. The pore hierarchy is achievable mainly because of the coupled effects of NaNH2 activation and the template/bubbling effects of byproducts of NaF and NH3. Electron microscopy studies and Brunauer–Emmett–Teller (BET) measurements confirm that the structures of HPC samples contain multiple-scale pores assembled in a hierarchical pattern, and most of their volumes are contributed by mesopores. Aqueous symmetric supercapacitors (ASSCs) were fabricated using HPC-M7 materials, achieving an ultrahigh specific energy of 18.8 Wh kg−1 at specific power of 986.8 W kg−1. Remarkably, at the ultrahigh power of 14.3 kW kg−1, the HPC-ASSCs still output a very high specific energy of 16.7 Wh kg−1, which means the ASSCs can be charged or discharged within 4 s. The outstanding rate capacitive performance is mainly benefited from the hierarchical porous structure that allows highly efficient ion diffusion.

This article proposed a combination of two algorithms, principal component analysis (PCA) and support vector machine (SVM), which was developed for face recognition. In the proposed technique, the face images were compressed into matrices using PCA and classified using SVM. To test and evaluate the performance of recognizing human faces, this project selected three face image databases, including Yale database, ORL database and Extended Yale Face Database B. All the face recognition rates were reasonable, and the highest face recognition rate was 98.75% for ORL database which subjects to training set number is 8 and 222 dimensions.

An aqueous dispersion of graphene oxide (GO) nanosheets with different oxygen content was obtained from graphite via oxidation and ultrasonication. The effects of GO nanosheets on the microstructure and mechanical properties of hardened cement paste were determined by scanning electron microscope, X-ray diffractometer and tensile/flexural/compressive strength investigations. The results indicate that GO nanosheets can regulate the formation of flower-like crystals and distinctly improve the tensile, flexural and compressive strengths of the corresponding hardened cement paste: when the oxygen content of GO was 25·45% and its dosage was 0·02% by weight of cement, the tensile strength and flexural strength increased by 197·2% and 184·5% respectively. These results suggest that GO nanosheets can significantly improve the toughness of hardened cement paste. A working mechanism is proposed by which GO may regulate the formation of hydration crystals by a template effect and thus exhibit significantly enhanced flexibility. The research results provide a potential new pathway to improve the toughness and reduce the cracking of cement composites.

Preparation and characterization of polycarboxylate superplasticizers of IPCs (copolymer of itaconic acid and allyl polyoxyethylene ether) and MPCs (copolymer of maleic anhydride and allyl polyoxyethylene ether) are shown. The difference between IPCs and MPCs is that half of the carboxyl groups of IPCs indirectly connect to the main chains through methylene. The effects of the carboxyl group-main chain connection mode on the properties of IPCs and MPCs were investigated by assessing the paste fluidity and the pore diameters and compressive strength. The interaction between IPCs (MPCs) and cement were revealed by zeta-potential and the adsorption amount. The results indicated that the indirect connection mode favorably improved paste fluidity, decreased pore diameters, and increased the compressive strength compared with the direct connection mode. This is likely because that when carboxyl groups are connected to the main chains indirectly, more moving space allows easier adsorption on cement particles. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

A phenol copolymer was synthesized by the free-radical copolymerization of p-hydroxybenzaldehyde (HBA) and p-phenolsulfonate with horseradish peroxidase (HRP)/H2O2 as an initiator. The synthesis process included aldehyde protection via acetalization, enzymatic polymerization, and aldehyde deprotection via hydrolysis of acetals. The effects of the monomer ratio and the HRP and H2O2 composites on the properties of poly(p-hydroxybenzaldehyde-co-p-phenolsulfonate) [poly(HBA-co-PS)] were investigated by the determination of the shrink temperature (Ts) of tanned leather. The poly(HBA-co-PS) structure was characterized by Fourier transform infrared spectroscopy, NMR, UV spectroscopy, and gel permeation chromatography. The mechanism of enzymatic copolymerization, including initiation, H transfer, radical transfer, coupling, termination, differed from that of traditional free-radical polymerization. A remarkable characteristic was that poly(HBA-co-PS) had a large conjugated structure in its molecules that markedly improved the activity of the aldehyde and hydroxyl groups and showed easy crosslinking in the leather fibers. The applied results showed that the Ts of tanned leather with poly(HBA-co-PS) reached 83.6°C. Poly(HBA-co-PS) could be used as agent for tanning leather. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013