422 research outputs found
A method of strain measurement based on fiber Bragg grating sensors
The equi-intensity cantilever beam experiments are designed and performed based on the theoretical research of Fiber Bragg Grating (FBG) sensing technology in this paper. The FBG sensor and the strain gauge are pasted on the surface of cantilever beam, the strain is produced by adding weights. The measurement data is obtained by data acquisition and processing. Compared with the measurement data result by strain gauge method, the measurement data from the FBG strain measurement method is closer with the theoretical calculating values. And the data result by FBG method have the advantages of excellent linearity and high precision, thus the strain measurement method based on FBG is accurate and feasible
Enzyme-mediated surface modification of jute and its influence on the properties of jute/epoxy composites
Surface modification of jute fibers is necessary to improve the adhesion and interfacial compatibility between fibers and resin matrix before using fibers in polymer composites. In this study, dodecyl gallate (DG) was enzymatically grafted onto the jute fiber by laccase to endow the fiber with hydrophobicity. A hand lay-up technique was then adopted to prepare jute/epoxy composites. Contact angle and wetting time measurements showed that the surface hydrophobicity of the jute fabric was increased after the enzymatic graft modification. The water absorption and thickness swelling of the DG-grafted jute fabric/epoxy composite were lower than those of the other composites. The tensile and dynamic mechanical properties of the jute/epoxy composites were enhanced by the surface modification. Scanning electron microscopy images revealed stronger fibermatrix adhesion in composites with modified fibers. Therefore, the enzymatic graft modification increased the fibermatrix interface area. The fibermatrix adhesion was enhanced, and the mechanical properties of the composites were improved.Contract grant sponsor: National Natural Science Foundation of China; contract grant number: 51173071; contract grant sponsor: Program for New Century Excellent Talents in University; contract grant number: NCET-12-0883; contract grant sponsor: Fundamental Research Funds for the Central Universities; contract grant sponsor: JUSRP51312B.info:eu-repo/semantics/publishedVersio
Effect of immobilized cellulase enzyme treatment on properties of ramie fabric
In this study, Eudragit S-100 has been covalently bound to the cellulase enzyme to form immobilized cellulase enzyme and then the effect of the treatment on ramie fabric properties is studied. The ramie fabrics treated with immobilized cellulase enzyme show lower quantities of reducing sugar, weight loss, and higher tensile strength than native cellulase enzyme-treated fabrics. Scanning electron microscopic analysis shows that the surface of ramie fabrics treated with cellulase enzyme is smoother than that of the untreated sample. Furthermore, treatment by the immobilized cellulase enzyme is less damaging to the fibres. X-ray diffraction studies show that there is hardly any loss in the crystallinity of ramie fabrics. Low-stress mechanical properties evaluated by the Kawabata Evaluation System for Fabric indicate that immobilized cellulase enzyme treatment improves the softness, flexibility, and elastic recovery of the ramie fabrics
Theoretical Investigation of the Formation Mechanism of NH3 and HCN during Pyrrole Pyrolysis: The Effect of H2O
Coal is a major contributor to the global emission of nitrogen oxides (NOx). The NOx formation during coal utilization typically derives from the thermal decomposition of N-containing compounds (e.g., pyrrolic groups). NH3 and HCN are common precursors of NOx from the decomposition of N-containing compounds. The existence of H2O has significant influences on the pyrrole decomposition and NOx formation. In this study, the effects of H2O on pyrrole pyrolysis to form NOx precursors HCN and NH3 are investigated using the density functional theory (DFT) method. The calculation results indicate that the presence of H2O can lead to the formation of both NH3 and HCN during pyrrole pyrolysis, while only HCN is formed in the absence of H2O. The initial interaction between pyrrole and H2O determines the N products. NH3 will be formed when H2O attacks the C2 position of pyrrole with its hydroxyl group. On the contrary, HCN will be generated instead of NH3 when H2O attacks the C3 position of pyrrole with its hydroxyl group. In addition, the DFT calculations clearly indicate that the formation of NH3 will be promoted by H2O, whereas the formation of HCN is inhibite
The mechanism of NLRP3 inflammasome activation and its pharmacological inhibitors
NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3) is a cytosolic pattern recognition receptor (PRR) that recognizes multiple pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). Once activated, NLRP3 initiates the inflammasome assembly together with the adaptor ASC and the effector caspase-1, leading to caspase-1 activation and subsequent cleavage of IL-1β and IL-18. Aberrant NLRP3 inflammasome activation is linked with the pathogenesis of multiple inflammatory diseases, such as cryopyrinÂassociated periodic syndromes, type 2 diabetes, non-alcoholic steatohepatitis, gout, and neurodegenerative diseases. Thus, NLRP3 is an important therapeutic target, and researchers are putting a lot of effort into developing its inhibitors. The review summarizes the latest advances in the mechanism of NLRP3 inflammasome activation and its pharmacological inhibitors
Single-cell sequencing reveals CD133+CD44--originating evolution and novel stemness related variants in human colorectal cancer
BACKGROUND: Tumor heterogeneity of human colorectal cancer (CRC)-initiating cells (CRCICs) in cancer tissues often represents aggressive features of cancer progression. For high-resolution examination of CRCICs, we performed single-cell whole-exome sequencing (scWES) and bulk cell targeted exome sequencing (TES) of CRCICs to investigate stemness-specific somatic alterations or clonal evolution. METHODS: Single cells of three subpopulations of CRCICs (CD133+CD44+, CD133-CD44+, and CD133+CD44- cells), CRC cells (CRCCs), and control cells from one CRC tissue were sorted for scWES. Then, we set up a mutation panel from scWES data and TES was used to validate mutation distribution and clonal evolution in additional 96 samples (20 patients) those were also sorted into the same three groups of CRCICs and CRCCs. The knock-down experiments were used to analyze stemness-related mutant genes. Neoantigens of these mutant genes and their MHC binding affinity were also analyzed. FINDINGS: Clonal evolution analysis of scWES and TES showed that the CD133+CD44- CRCICs were the likely origin of CRC before evolving into other groups of CRCICs/CRCCs. We revealed that AHNAK2, PLIN4, HLA-B, ALK, CCDC92 and ALMS1 genes were specifically mutated in CRCICs followed by the validation of their functions. Furthermore, four predicted neoantigens of AHNAK2 were identified and validated, which might have applications in immunotherapy for CRC patients. INTERPRETATION: All the integrative analyses above revealed clonal evolution of CRC and new markers for CRCICs and demonstrate the important roles of CRCICs in tumorigenesis and progression of CRCs. FUNDING: A full list of funding bodies that contributed to this study can be found in the Acknowledgements section
Deep Learning based 3D Segmentation: A Survey
3D object segmentation is a fundamental and challenging problem in computer
vision with applications in autonomous driving, robotics, augmented reality and
medical image analysis. It has received significant attention from the computer
vision, graphics and machine learning communities. Traditionally, 3D
segmentation was performed with hand-crafted features and engineered methods
which failed to achieve acceptable accuracy and could not generalize to
large-scale data. Driven by their great success in 2D computer vision, deep
learning techniques have recently become the tool of choice for 3D segmentation
tasks as well. This has led to an influx of a large number of methods in the
literature that have been evaluated on different benchmark datasets. This paper
provides a comprehensive survey of recent progress in deep learning based 3D
segmentation covering over 150 papers. It summarizes the most commonly used
pipelines, discusses their highlights and shortcomings, and analyzes the
competitive results of these segmentation methods. Based on the analysis, it
also provides promising research directions for the future.Comment: Under review of ACM Computing Surveys, 36 pages, 10 tables, 9 figure
A New Insight into the Role of CART in Cocaine Reward: Involvement of CaMKII and Inhibitory G-Protein Coupled Receptor Signaling
Cocaine- and amphetamine-regulated transcript (CART) peptides are neuropeptides that are expressed in brain regions associated with reward, such as the nucleus accumbens (NAc), and play a role in cocaine reward. Injection of CART into the NAc can inhibit the behavioral effects of cocaine, and injecting CART into the ventral tegmental area (VTA) reduces cocaine-seeking behavior. However, the exact mechanism of these effects is not clear. Recent research has demonstrated that Ca2+/calmodulin-dependent protein kinase II (CaMKII) and inhibitory G-protein coupled receptor (GPCR) signaling are involved in the mechanism of the effect of CART on cocaine reward. Hence, we review the role of CaMKII and inhibitory GPCR signaling in the effect of CART on cocaine reward and provide a new insight into the mechanism of that effect. In this article, we will first review the biological function of CART and discuss the role of CART in cocaine reward. Then, we will focus on the role of CaMKII and inhibitory GPCR signaling in cocaine reward. Furthermore, we will discuss how CaMKII and inhibitory GPCR signaling are involved in the mechanistic action of CART in cocaine reward. Finally, we will provide our opinions regarding the future directions of research on the role of CaMKII and inhibitory GPCR signaling in the effect of CART on cocaine reward
- …