189 research outputs found
Scan2Drawing: Use of Deep Learning for As-Built Model Landscape Architecture
This paper presents an innovative and fully automatic solution of generating as-built computer-aided design (CAD) drawings for landscape architecture (LA) with three dimensional (3D) reality data scanned via drone, camera, and LiDAR. To start with the full pipeline, 2D feature images of ortho-image and elevation-map are converted from the reality data. A deep learning-based light convolutional encoder–decoder was developed, and compared with U-Net (a binary segmentation model), for image pixelwise segmentation to realize automatic site surface classification, object detection, and ground control point identification. Then, the proposed elevation clustering and segmentation algorithms can automatically extract contours for each instance from each surface or object category. Experimental results showed that the developed light model achieved comparable results with U-Net in landing pad segmentation with average intersection over union (IoU) of 0.900 versus 0.969. With the proposed data augmentation strategy, the light model had a testing pixel accuracy of 0.9764 and mean IoU of 0.8922 in the six-class segmentation testing task. Additionally, for surfaces with continuous elevation changes (i.e., ground), the developed algorithm created contours only have an average elevation difference of 1.68 cm compared to dense point clouds using drones and image-based reality data. For objects with discrete elevation changes (i.e., stair treads), the generated contours accurately represent objects’ elevations with zero difference using light detection and ranging (LiDAR) data. The contribution of this research is to develop algorithms that automatically transfer the scanned LA scenes to contours with real-world coordinates to create as-built computer-aided design (CAD) drawings, which can further assist building information modeling (BIM) model creation and inspect the scanned LA scenes with augmented reality. The optimized parameters for the developed algorithms are analyzed and recommended for future applications
Efficient Multi-Scale Attention Module with Cross-Spatial Learning
Remarkable effectiveness of the channel or spatial attention mechanisms for
producing more discernible feature representation are illustrated in various
computer vision tasks. However, modeling the cross-channel relationships with
channel dimensionality reduction may bring side effect in extracting deep
visual representations. In this paper, a novel efficient multi-scale attention
(EMA) module is proposed. Focusing on retaining the information on per channel
and decreasing the computational overhead, we reshape the partly channels into
the batch dimensions and group the channel dimensions into multiple
sub-features which make the spatial semantic features well-distributed inside
each feature group. Specifically, apart from encoding the global information to
re-calibrate the channel-wise weight in each parallel branch, the output
features of the two parallel branches are further aggregated by a
cross-dimension interaction for capturing pixel-level pairwise relationship. We
conduct extensive ablation studies and experiments on image classification and
object detection tasks with popular benchmarks (e.g., CIFAR-100, ImageNet-1k,
MS COCO and VisDrone2019) for evaluating its performance.Comment: Accepted to ICASSP202
α-Synuclein: A Multifunctional Player in Exocytosis, Endocytosis, and Vesicle Recycling
α-synuclein (α-Syn) is a presynaptic enriched protein involved in the pathogenesis of Parkinson’s disease. However, the physiological roles of α-Syn remain poorly understood. Recent studies have indicated a critical role of α-Syn in the sensing and generation of membrane curvature during vesicular exocytosis and endocytosis. It has been known to modulate the assembly of SNARE complex during exocytosis including vesicle docking, priming and fusion steps. Growing evidence suggests that α-Syn also plays critical roles in the endocytosis of synaptic vesicles. It also modulates the availability of releasable vesicles by promoting synaptic vesicles clustering. Here, we provide an overview of recent progresses in understanding the function of α-Syn in the regulation of exocytosis, endocytosis, and vesicle recycling under physiological and pathological conditions
Clinical Study Simple and Robust Analysis of Cefuroxime in Human Plasma by LC-MS/MS: Application to a Bioequivalence Study
A simple, robust LC-MS/MS assay for quantifying cefuroxime in human plasma was developed. Cefuroxime and tazobactam, as internal standard (IS), were extracted from human plasma by methanol to precipitate protein. Separation was achieved on a Zorbax SB-Aq (4.6 × 250 mm, 5 m) column under isocratic conditions. The calibration curve was linear in the concentration range of 0.0525-21.0 g/mL ( = 0.9998). The accuracy was higher than 90.92%, while the intra-and interday precision were less than 6.26%. The extraction procedure provides recovery ranged from 89.44% to 92.32%, for both analyte and IS. Finally, the method was successfully applied to a bioequivalence study of a single 500 mg dose of cefuroxime axetil in 22 healthy Chinese male subjects under fasting condition. Bioequivalence was determined by calculating 90% Cls for the ratios of max , AUC 0− , and AUC 0−∞ values for the test and reference products, using logarithmic transformed data. The 90% Cls for the ratios of max (91.4%∼104.2%), AUC 0− (97.4%∼110.9%), and AUC 0−∞ (97.6%∼111.1%) values were within the predetermined range. It was concluded that the two formulations (test for capsule, reference for tablet) analyzed were bioequivalent in terms of rate and extent of absorption and the method met the principle of quick and easy clinical analysis
Research Advances in the Refining of Polysaccharides and the Mechanism for Its Effect on Reducing the Toxicity and Enhancing the Efficacy of Cyclophosphamide
Anticancer chemotherapy with cyclophosphamide (CTX) is accompanied by toxic side effects such as bone marrow suppression and intestinal mucosal injury, which seriously affects the treatment tolerance and prognosis of patients. In recent years, polysaccharides have been used as detoxifying and synergistic adjuncts for antitumor drugs due to their anticancer, anti-inflammatory, and immunoregulatory activities. This paper systematically summarizes polysaccharide purification technologies, elaborates on the detoxification mechanism of polysaccharides on CTX from multiple perspectives such as immunomodulation, antioxidation, intestinal protection, liver and kidney protection, and reproductive system protection, and discusses the synergistic effect of polysaccharides with CTX by directly or indirectly killing tumors. Furthermore, the regulatory pathways of polysaccharides in cancer chemotherapy are summarized from two aspects: toxicity reduction and efficacy enhancement. We hope that this review could provide a reference for research on the mechanism of action of polysaccharides in reducing the toxicity and enhancing the efficacy of CTX, and provide new directions for reducing the toxic side effects of CTX
Independent Association of Serum Fibroblast Growth Factor 21 Levels With Impaired Liver Enzymes in Hyperthyroid Patients
Fibroblast growth factor 21 (FGF21) is identified as a potential biomarker for liver diseases. However, information is limited regarding serum FGF21 and impaired liver function in hyperthyroidism. We aim to determine the potential association of serum FGF21 levels with impaired liver enzymes in hyperthyroid patients. In this case-control study, 105 normal subjects and 122 overt hyperthyroid patients were included. Among them, 41 hyperthyroid patients who obtained euthyroid status after thionamide treatment received second visit. Serum FGF21 levels were determined using the ELISA method. Compared to the normal subjects, patients with hyperthyroidism had significantly elevated serum liver enzymes, including alanine transaminase (ALT) (p < 0.001), aspartate aminotransferase (AST) (p < 0.001) levels, as well as FGF21 levels (p < 0.001). Further analysis showed serum FGF21 (p < 0.05), as well as thyroid hormone (TH) free T3 (p < 0.05), free T4 (p < 0.05) levels were higher in hyperthyroid patients with impaired liver enzymes than in those with normal liver enzymes. After reversal of hyperthyroid state, elevated serum FGF21 levels in hyperthyroid patients declined significantly (p < 0.001), with a concomitant decrease in serum ALT (p < 0.001), AST (p < 0.001) levels. Correlation analysis showed close correlation between FGF21 and ALT (p < 0.002), AST (p < 0.012), free T3 (p < 0.001), free T4 (p < 0.001). Further logistic regression analysis revealed FGF21 is significantly associated with elevated ALT [Odds Ratio, OR 1.79, (95% confidence interval, CI), (1.30–2.47), P < 0.001], AST [1.59 (1.07–2.34), p < 0.020]. After adjustment of potential confounders, the association between FGF21 and elevated ALT remained significant [1.42 (1.01–1.99), p < 0.043]. In conclusion, serum FGF21 is independently associated with impaired liver enzymes in hyperthyroid patients
Enhancement of Er3+ emission from an Er-Si codoped Al 2O3 film by stacking Si-doped Al2O3 sublayers
A multilayer film (multi-film), consisting of alternate Er-Si-codoped Al2O3 (ESA) and Si-doped Al2O3 (SA) sublayers, is synthesized by co-sputtering from separated Er, Si, and Al 2O3 targets. The dependence of Er3+ related photoluminescence (PL) properties on annealing temperatures over 700-1100°C is studied. The maximum intensity of Er3+ photoluminance (PL), about 10 times higher than that of the monolayer film, is obtained from the multi-film annealed at 950°C. The enhancement of Er3+ PL intensity is attributed to the energy transfer from the silicon nanocrystals (Si-NCs) to the neighboring Er3+ ions. The effective characteristic interaction distance (or the critical ET length) between Er and carriers (Si-NCs) is ∼3 nm. The PL intensity exhibits a nonmonotonic temperature dependence. Meanwhile, the PL integrated intensity at room temperature is about 30% higher than that at 14 K. © 2011 Chinese Physical Society and IOP Publishing Ltd.Peer Reviewe
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