A new glycoside, recurvataside (1) and six known compounds, quinovic acid (2), quinovic acid 28-O-β-D-glucopyranosyl ester (3), 3-O-β-D-glucopyranosylquinovic acid (4), 3-O-β-Dglucopyranosylquinovic acid 28-O-β-D-glucopyranosyl ester (5), pomolic acid (6), and ursolic acid (7) were isolated from aerial parts of Mussaenda recurvata. The structure of compound 1 was identified from its spectroscopic data and by comparison with the literature.Recurvataside represents the first occurrence of δ-oleanolic acid saponin bearing two Dglucose units at C-3 and C-28 in nature. This is the first time δ-oleanane-type saponin reported in the genus Mussaenda. Compounds 1-7 were evaluated the cytotoxicity against two cancer cell lines MCF-7 and HepG2. Among them, only compound 7 exhibited moderate activity against MCF-7 and HepG2 cell lines with IC 50 value of 16.97 ± 1.55 and 20.28 ± 1.00 μM, respectively. Compounds 1-7 were also tested for their inhibitory NO production in LPS-stimulated RAW264.7 cells. Compounds 3, 5, and 7 showed significant reduction of nitrite accumulation in LPS-stimulated RAW 264.7 cells with the IC 50 values of 8. 81 ± 0.48, 13.42 ± 0.84, and 18.37 ± 0.67 μM, respectively
Purpose
– The purpose of this paper is to present a low-cost, highly mobile system for performing street-level imaging. Street-level imaging and geo-location-based services are rapidly growing in both popularity and coverage. Google Street View and Bing StreetSide are two of the free, online services which allow users to search location-based information on interactive maps. In addition, these services also provide software developers and researchers a rich source of street-level images for different purposes – from identifying traffic routes to augmented reality applications. Currently, coverage for Street View and StreetSide is limited to more affluent Western countries with sparse coverage throughout south-east Asia and Africa. In this paper, we present a low-cost system to perform street-level imaging targeted towards the congested, motorcycle-dominant south-east Asian countries. The proposed system uses a catadioptric imaging system to capture 360-degree panoramic images which are geo-located using an on-board GPS. The system is mounted on the back of a motorcycle to provide maximum mobility and access to narrow roads. An innovative backwards remapping technique for flattening the images is discussed along with some results from the first 150 km which have been captured from Southern Vietnam.
Design/methodology/approach
– The design was a low-cost prototype design using low-cost off-the-shelf hardware with custom software and assembly to facilitate functionality.
Findings
– The system was shown to work well as a low-cost omnidirectional mapping solution targeted toward sea-of-motorbike road conditions.
Research limitations/implications
– Some of the pictures returned by the system were unclear. These could be improved by having artificial lighting (currently only ambient light is used), a gyroscope-stabilised imaging platform and a higher resolution camera.
Originality/value
– This paper discusses a design which facilitates low-cost, street-level imaging for a sea-of-motorcycle environment. The system uses a catadioptric imaging approach to give a wide field of view without excessive image storage requirements using dozens of cameras.
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