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"Wang, Ren-Wei"
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Automated Optical Inspection for Defect Identification and Classification in Actual Woven Fabric Production Lines
This paper presents a turnkey integrated system that can be operated in real time for real textile manufacturers. Eight types of defects in woven fabric, including stain, broken end, broken weft, hole, nep, double pick, kinky weft and float can be recognized and classified. First, an image is captured by a CMOS industrial camera with a pixel size of 4600 × 600 above the batcher at 20 m/min. After that, the four-stage image processing procedure is applied to detect defects and for classification. Stage 1 is image pre-processing; the filtration of the image noise is carried out by a Gaussian filter. The light source is corrected to reduce the uneven brightness resulting from halo formation. The improved mask dodging algorithm is used to reduce the standard deviation of the corrected original image. Afterwards, the background texture is filtered by an averaging filter, and the mean value is corrected for histogram shifting, so that this system is robust to the texture and color changes of woven fabric. The binary segmentation threshold is determined using the mean value and standard deviation of an image with a normal sample. Stage 2 uses adaptive binarization for separation of the background and defects and to filter the noise. In Stage 3, the morphological processing is used before the defect contour is circled, i.e., four features of each block, including the defect area, the aspect ratio of the defect, the average gray level of the defect and the defect orientation, which are calculated according to the range of contour. The image defect recognition dataset consists of 2246 images. The results show that the detection success rate is 96.44%, and the false alarm rate is 3.21%. In Stage 4, the defect classification is implemented. The support vector machine (SVM) is used for classification, 230 defect images are used as training samples, and 206 are used as test samples. The experimental results show that the overall defect recognition rate is 96.60%, providing that the software and hardware equipment designed in this study can implement defect detection and classification for woven fabric effectively.
Journal Article
Automatic marking point positioning of printed circuit boards based on template matching technique
The traditional global template matching is time consuming, has low accuracy, and cannot be adapted to rotation and scale change. The template matching technique proposed in this study improves the time, accuracy and robustness for printed circuit boards (PCB). In order to shorten the image positioning time, the image preprocessing is implemented on PCB image and the image blocks are labeled to obtain the tagged image, and the feature vector is extracted and the marking point region image is selected. The feature vector with rotation change and scale change robustness is extracted from the tagged image after labeling in the PCB image by using artificial neural network, combined with image moments for training. The marking point region image in the PCB image is selected. The scale value of the marking point region image is estimated by parametric template vector matching. The deflection angle of marking point region image is calculated by Hough transform. The obtained scale value and deflection angle value are used for fast template matching to determine the marking point positioning. The three-dimensional (3D) parabolic curve fitting is implemented in marking point positioning and adjacent pixel position to reach the sub-pixel level accuracy. The experiment showed that the proposed template matching technique for the PCB image with or without noise or angle rotation, the average position accuracy error of each translated image is lower than 7 \\[\\upmu \\]m, and the error standard deviation is lower than 5 \\[\\upmu \\]m. The rotation angle error average and standard deviation of angular error of Hough transform are lower than 0.2\\[^{\\circ }\\], more accurate than orientation code (OC) method. The scale value estimation, relative error average and error standard deviation are lower than 0.004 and 0.006 for the image with or without noise. The average complete positioning time of PCB image at resolution of \\[2500\\times 2500\\] is only 0.55 s, which is better than the 3.97 s of traditional global template matching. The results prove that the template matching technique of this study not only has sub-pixel level high accuracy and short computing time, but also has the robustness of rotation change and scale change interference. It can implement rapid, efficient and accurate positioning.
Journal Article
Motor cortex stimulation ameliorates parkinsonian locomotor deficits: effectual and mechanistic differences from subthalamic modulation
Subthalamic deep brain stimulation (STN DBS) has been a therapeutic choice for Parkinson’s disease (PD). We found that epidural motor cortex stimulation (MCS) with sustained positive (hyperpolarizing) currents could also consistently ameliorate the locomotor deficits in parkinsonian animals, rectifying the pathological paucity in both discharging unit varieties and movement-dependent spatiotemporal activity pattern changes in motor cortex (MC). Mechanistically, MCS hyperpolarizes both glutamatergic pyramidal neurons (PN) and GABAergic interneurons (IN) and consequently partly relieves PN from IN’s control. MC discharging units are thus enlarged with enhanced PN burst discharges against a relatively silenced background, presumably compensating for the hypoactive striatal selection to restore the MC activity changes upon movement. Behaviorally, MCS retains interim short pauses like normal locomotor behaviors, in contrast to the propensity of abnormal “restlessness” with STN DBS. Individually designed MCS, alone or in combination with STN DBS and dopaminergic therapy, may provide an optimal therapeutic approach for PD.
Journal Article
Deep brain stimulation rectifies the noisy cortex and irresponsive subthalamus to improve parkinsonian locomotor activities
The success of deep brain stimulation (DBS) therapy indicates that Parkinson’s disease is a brain rhythm disorder. However, the manifestations of the erroneous rhythms corrected by DBS remain to be established. We found that augmentation of α rhythms and α coherence between the motor cortex (MC) and the subthalamic nucleus (STN) is characteristically prokinetic and is decreased in parkinsonian rats. In multi-unit recordings, movement is normally associated with increased changes in spatiotemporal activities rather than overall spike rates in MC. In parkinsonian rats, MC shows higher spike rates at rest but less spatiotemporal activity changes upon movement, and STN burst discharges are more prevalent, longer lasting, and less responsive to MC inputs. DBS at STN rectifies the foregoing pathological MC-STN oscillations and consequently locomotor deficits, yet overstimulation may cause behavioral restlessness. These results indicate that delicate electrophysiological considerations at both cortical and subcortical levels should be exercised for optimal DBS therapy.
Journal Article
Effectiveness of LiuZiJue Qigong versus traditional core stability training for poststroke patients complicated with abnormal trunk postural control: study protocol for a single-center randomized controlled trial
Background
Trunk function in stroke patients with hemiplegia is associated with respiration and core stability and is also found to be associated with balance and postural control and activities of daily living. LiuZiJue Qigong (LQG) is a traditional Chinese method of fitness based on breath pronunciation. The purpose of this study is to compare the clinical efficacy of LQG and traditional core stability training in the treatment of stroke patients with abnormal trunk posture. This protocol is written according to the SPIRIT 2013 statement.
Methods/design
This study is a single-center randomized controlled trial in which 160 stroke patients are randomly divided into a study group and a control group. Patients in the study group will receive LQG combined with conventional rehabilitation therapy, and patients in the control group will receive traditional core stability training combined with conventional rehabilitation therapy. All treatments will be done for 45 min/day, five times per week, for 2 weeks. The primary outcome (Trunk Impairment Scale) and secondary outcomes (Berg Balance Scale, Fugl-Meyer Assessment, Modified Barthel Index, Maximum Phonation Time, Dynamic and Static balance testing, and thickness and the mobile degrees of diaphragm) will be measured at baseline, 2 weeks, and the end of the rehabilitation course.
Discussion
The aim purpose of this research study is to compare the clinical efficacy of LQG and traditional core stability exercise in the treatment of stroke patients with abnormal trunk posture.
Trial registration
Chinese Clinical Trial Register,
ChiCTR1800014864
. Registered on 24 November 2018.
Journal Article
Effect of charged amino acid side chain length on lateral cross-strand interactions between carboxylate- and guanidinium-containing residues in a β-hairpin
β-Sheet is one of the major protein secondary structures. Oppositely charged residues are frequently observed across neighboring strands in antiparallel sheets, suggesting the importance of cross-strand ion pairing interactions. The charged amino acids Asp, Glu, Arg, and Lys have different numbers of hydrophobic methylenes linking the charged functionality to the backbone. To investigate the effect of side chain length of guanidinium- and carboxylate-containing residues on lateral cross-strand ion pairing interactions at non-hydrogen-bonded positions, β-hairpin peptides containing Zbb-Agx (Zbb = Asp, Glu, Aad in increasing length; Agx = Agh, Arg, Agb, Agp in decreasing length) sequence patterns were studied by NMR methods. The fraction folded population and folding energy were derived from the chemical shift deviation data. Peptides with high fraction folded populations involved charged residue side chain lengths that supported high strand propensity. Double mutant cycle analysis was used to determine the interaction energy for the potential lateral ion pairs. Minimal interaction was observed between residues with short side chains, most likely due to the diffused positive charge on the guanidinium group, which weakened cross-strand electrostatic interactions with the carboxylate side chain. Only the Aad-Arg/Agh interactions with long side chains clearly exhibited stabilizing energetics, possibly relying on hydrophobics. A survey of a non-redundant protein structure database revealed that the statistical sheet pair propensity followed the trend Asp-Arg < Glu-Arg, implying the need for matching long side chains. This suggested the need for long side chains on both guanidinium-bearing and carboxylate-bearing residues to stabilize the β-hairpin motif.
Journal Article
Helix formation and capping energetics of arginine analogs with varying side chain length
Arginine (Arg) has been used for recognizing negatively charged biological molecules, cell penetration, and oligosaccharide mass signal enhancement. The versatility of Arg has inspired the need to develop Arg analogs and to research the structural effects of incorporating Arg analogs. Accordingly, we investigated the effect of Arg side chain length on helix formation by studying 12 Ala-based peptides containing the Arg analogs (
S
)-2-amino-6-guanidino-hexanoic acid (Agh), (
S
)-2-amino-4-guanidinobutyric acid (Agb), and (
S
)-2-amino-3-guanidinopropionic acid (Agp). Solid phase guanidinylation with orthogonal protection strategies was necessary to synthesize Agb- and Agp-containing peptides using Fmoc-based chemistry. The fraction helix for the peptides was determined by circular dichroism spectroscopy, and used to derive the statistical mechanical parameters and energetics for N-capping, C-capping, and helix propagation (propensity). All four Arg analogs were unfavorable for N-capping. The C-cap parameter followed the trend Agp < Agb < Arg < Agh, showing more favorable C-cap energetics with increasing side chain length. In contrast, helix propensity followed the trend Agp < Agb < Arg > Agh, highlighting the uniqueness of the Arg side chain length in helix formation. Molecular mechanics calculations and a survey on protein structures were consistent with the experimental results. Furthermore, calculations and survey both showed that the
g
– conformation for the χ
1
dihedral was present for the first two residues at the N-terminus of helices, but not favored in the center or C-terminus of helices due to sterics. These results should serve as the foundation for developing Arg-related bioactive compounds and technologies.
Journal Article
Effect of side chain length on intrahelical interactions between carboxylate- and guanidinium-containing amino acids
The charge-containing hydrophilic functionalities of encoded charged amino acids are linked to the backbone via different numbers of hydrophobic methylenes, despite the apparent electrostatic nature of protein ion pairing interactions. To investigate the effect of side chain length of guanidinium- and carboxylate-containing residues on ion pairing interactions, α-helical peptides containing Zbb–Xaa (
i
,
i
+ 3), (
i
,
i
+ 4) and (
i
,
i
+ 5) (Zbb = carboxylate-containing residues Aad, Glu, Asp in decreasing length; Xaa = guanidinium residues Agh, Arg, Agb, Agp in decreasing length) sequence patterns were studied by circular dichroism spectroscopy (CD). The helicity of Aad- and Glu-containing peptides was similar and mostly pH independent, whereas the helicity of Asp-containing peptides was mostly pH dependent. Furthermore, the Arg-containing peptides consistently exhibited higher helicity compared to the corresponding Agp-, Agb-, and Agh-containing peptides. Side chain conformational analysis by molecular mechanics calculations showed that the Zbb–Xaa (
i
,
i
+ 3) and (
i
,
i
+ 4) interactions mainly involved the
χ
1
dihedral combinations (
g
+,
g
+) and (
g
−,
g
+), respectively. These low energy conformations were also observed in intrahelical Asp–Arg and Glu–Arg salt bridges of natural proteins. Accordingly, Asp and Glu provides variation in helix characteristics associated with Arg, but Aad does not provide features beyond those already delivered by Glu. Importantly, nature may have chosen the side chain length of Arg to support helical conformations through inherent high helix propensity coupled with stabilizing intrahelical ion pairing interactions with the carboxylate-containing residues.
Journal Article
Successful Renal Transplantation in a Patient with Atypical Hemolytic Uremic Syndrome Treated with Eculizumab in China
Hemolytic uremic syndrome （HUS） is a rare disease characterized by thrombocytopenia and acute renal failure. Atypical HUS （aHUS） accounts for approximately 10% of all HUS cases. The pathogenesis of aHUS is mainly associated with gene mutations in complement factor H, complement factor I, and membrane cofactor protein （MCP）. The prognosis of aHUS is generally poor.
Journal Article