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1.
Sensors (Basel) ; 23(12)2023 Jun 14.
Article in English | MEDLINE | ID: mdl-37420726

ABSTRACT

This paper proposes the design of a 360° map establishment and real-time simultaneous localization and mapping (SLAM) algorithm based on equirectangular projection. All equirectangular projection images with an aspect ratio of 2:1 are supported for input image types of the proposed system, allowing an unlimited number and arrangement of cameras. Firstly, the proposed system uses dual back-to-back fisheye cameras to capture 360° images, followed by the adoption of the perspective transformation with any yaw degree given to shrink the feature extraction area in order to reduce the computational time, as well as retain the 360° field of view. Secondly, the oriented fast and rotated brief (ORB) feature points extracted from perspective images with a GPU acceleration are used for tracking, mapping, and camera pose estimation in the system. The 360° binary map supports the functions of saving, loading, and online updating to enhance the flexibility, convenience, and stability of the 360° system. The proposed system is also implemented on an nVidia Jetson TX2 embedded platform with 1% accumulated RMS error of 250 m. The average performance of the proposed system achieves 20 frames per second (FPS) in the case with a single-fisheye camera of resolution 1024 × 768, and the system performs panoramic stitching and blending under 1416 × 708 resolution from a dual-fisheye camera at the same time.


Subject(s)
Acceleration , Algorithms , Autonomous Vehicles , Records
2.
Environ Toxicol ; 31(11): 1293-1306, 2016 Nov.
Article in English | MEDLINE | ID: mdl-25758670

ABSTRACT

Smoking increases the risk of cardiovascular disorders and leads to damage caused by inflammation and oxidative stress. The actin cytoskeleton is a key player in the response to inflammatory stimuli and is an early target of cellular oxidative stress. The purpose of this study was to investigate the changes in actin cytoskeleton dynamics in human endothelial EA.hy926 cells exposed to cigarette smoke extract (CSE). Immunostaining revealed that CSE exposure resulted in modification of the actin cytoskeleton and led to cell rounding in a dose- and time-dependent manner. In addition, the intracellular calcium concentration was increased by treatment with CSE. Pretreatment with antioxidants (lipoic acid, glutathione, N-acetyl cysteine, aminoguanidine, α-tocopherol, and vitamin C) significantly attenuated the CSE-induced actin cytoskeleton reorganization and cell rounding. Calcium ion chelators (EGTA, BAPTA-AM AM) and a potent store-operated calcium channel inhibitor (MRS 1845) also reduced CSE-induced intracellular calcium changes and attenuated actin cytoskeleton reorganization and cell morphology change. Moreover, the CSE-induced intracellular calcium increase was suppressed by pretreatment with the inositol trisphosphate receptor (IP3R) inhibitor xestospongin C, the phospholipase C (PLC) inhibitor U-73122, and the protein kinase C (PKC) inhibitor GF109203X. These results suggest that reactive oxygen species production and intracellular calcium increase play an essential role in CSE-induced actin disorganization and cell rounding through a PLC-IP3-PKC signaling pathway. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1293-1306, 2016.


Subject(s)
Actin Cytoskeleton/metabolism , Calcium Signaling , Inositol 1,4,5-Trisphosphate Receptors/metabolism , Nicotiana/chemistry , Smoke , Acetylcysteine/pharmacology , Actin Cytoskeleton/drug effects , Antioxidants/pharmacology , Calcium Signaling/drug effects , Cell Line , Chelating Agents/pharmacology , Endothelial Cells/cytology , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Estrenes/pharmacology , Glutathione/metabolism , Humans , Indoles/pharmacology , Inositol 1,4,5-Trisphosphate Receptors/antagonists & inhibitors , Macrocyclic Compounds/pharmacology , Maleimides/pharmacology , Microscopy, Fluorescence , Nitrendipine/analogs & derivatives , Nitrendipine/pharmacology , Oxazoles/pharmacology , Oxidative Stress/drug effects , Protein Kinase C/antagonists & inhibitors , Protein Kinase C/metabolism , Pyrrolidinones/pharmacology , Reactive Oxygen Species/metabolism , Nicotiana/metabolism , Type C Phospholipases/antagonists & inhibitors , Type C Phospholipases/metabolism
3.
J Agric Food Chem ; 58(19): 10364-72, 2010 Oct 13.
Article in English | MEDLINE | ID: mdl-20839771

ABSTRACT

Mature Basella alba L. fruit, with dark blue skin and deep red-violet flesh, is a potential source of natural colorants. Its pigment components and bioactivities deserve particular attention and investigation. In this study, fruit flesh was extracted with 80% methanol (containing 0.2% formic acid) and subjected to solid-phase extraction, semipreparative HPLC isolation, mass spectrophotometric analysis, and structural elucidation. The major red pigment was identified as gomphrenin I. Its quantity increased with the increase of fruit maturity. The gomphrenin I extract yield from ripe fruits was 36.1 mg/100 g of fresh weight. In addition to gomphrenin I, betanidin-dihexose and isobetanidin-dihexose were also detected. The antioxidant activities of gomphrenin I determined by Trolox equivalent antioxidant capacity (TEAC), α,α-diphenyl-ß-picrylhydrazyl (DPPH) radical scavenging activity, reducing power, and antioxidative capacity assays were equivalent to 534 µM Trolox, 103 µM butylated hydroxytoluene (BHT), 129 µM ascorbic acid, and 68 µM BHT at 180, 23, 45, and 181 µM, respectively. The anti-inflammatory function was tested at concentrations of 25, 50, and 100 µM in murine macrophages stimulated with lipopolysaccharide (LPS). The results revealed that gomphrenin I suppressed LPS-induced nitric oxide (NO) production in a dose-dependent manner and decreased PGE(2) and IL-1ß secretions at the highest concentration tested. The transcriptional inhibitory activities of gomphrenin I on the expression of inflammatory genes encoding iNOS, COX-2, IL-1ß, TNF-α, and IL-6 were also observed. It is of merit to identify gomphrenin I as a principal pigment of B. alba fruits and as a potent antioxidant and inflammatory inhibitor. These findings suggest that B. alba fruit is a rich source of betalains and has value-added potential for use in the development of food colorants and nutraceuticals.


Subject(s)
Betalains/analysis , Betalains/pharmacology , Ferns/chemistry , Fruit/chemistry , Pigments, Biological/analysis , Pigments, Biological/pharmacology , Animals , Anti-Inflammatory Agents/analysis , Anti-Inflammatory Agents/pharmacology , Antioxidants/analysis , Antioxidants/pharmacology , Betalains/chemistry , Drug Stability , Fruit/growth & development , Hot Temperature , Macrophages/drug effects , Mice , Pigments, Biological/chemistry
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