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Fulltext Underwater Turbulence Detection Using Gated Wavefront Sensing Technique

Bi Y, Xu X, Chua SY, Chow EMT, Wang X

Sensors (Basel), 2018 Mar 07;18(3).
PMID: 29518889 DOI: 10.3390/s18030798

Laser sensing has been applied in various underwater applications, ranging from underwater detection to laser underwater communications. However, there are several great challenges when profiling underwater turbulence effects. Underwater detection is greatly affected by the turbulence effect, where the acquired image suffers excessive noise, blurring, and deformation. In this paper, we propose a novel underwater turbulence detection method based on a gated wavefront sensing technique. First, we elaborate on the operating principle of gated wavefront sensing and wavefront reconstruction. We then setup an experimental system in order to validate the feasibility of our proposed method. The effect of underwater turbulence on detection is examined at different distances, and under different turbulence levels. The experimental results obtained from our gated wavefront sensing system indicate that underwater turbulence can be detected and analyzed. The proposed gated wavefront sensing system has the advantage of a simple structure and high detection efficiency for underwater environments.
Fulltext Comparative pharmacokinetics of a proliposome formulation of Ginkgo biloba extract and Ginaton in rats by a sensitive ultra performance liquid chromatography-tandem mass spectrometry method

Zheng B, Xing G, Bi Y, Yan G, Wang J, Cheng Y, et al.

Saudi J Biol Sci, 2016 Jan;23(1):54-65.
PMID: 26858539 DOI: 10.1016/j.sjbs.2015.08.009

As a novel oral drug delivery system, proliposome was applied to improve the solubility of active components of Ginkgo biloba extract (GbE). There are currently few reports focusing on the pharmacokinetic characteristics of proliposome of GbE (GbP). A rapid and sensitive ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous quantification of active components of GbP and a commercial tablet product (Ginaton) in rat plasma was developed and successfully validated. The method was applied to the comparative pharmacokinetic evaluation of GbP and Ginaton in rat plasma. The results indicated that GbP has a significant effect on absorption, elimination and bioavailability of flavonoids and terpenoid lactones in comparison with Ginaton. The obtained results would be helpful for evaluating the absorption mechanism in the gastrointestinal tract in pharmacokinetic level and guiding the development of the novel oral drug delivery system.
High altitude species, high profits: Can the trade in wild harvested Fritillaria cirrhosa (Liliaceae) be sustained?

Cunningham AB, Brinckmann JA, Pei SJ, Luo P, Schippmann U, Long X, et al.

J Ethnopharmacol, 2018 Sep 15;223:142-151.
PMID: 29751123 DOI: 10.1016/j.jep.2018.05.004

ETHNOPHARMACOLOGICAL RELEVANCE: Fritillaria cirrhosa D. Don bulbs contain alkaloids and are one of the most intensively exploited alpine Himalayan medicinal species. In terms of proprietary medicines, our study shows that 210 F. cirrhosa products are offered by 46 suppliers, most of which (44) are situated in China and two in Nepal. A widespread commercial use is as one of the main ingredients in cough syrups. A well known example is "Nin Jiom Pei Pa Koa Herbal Cough & Throat Syrup", which typically contains more F. cirrhosa than any other herbal ingredient in the formulation. The biggest market for F. cirrhosa bulbs is China, where demand exceeds supply of this wild harvested species for use in traditional Chinese medicine (TCM). Cross-border trade from Nepal to China occurs in significant quantities. Bhutan also imports F. cirrhosa bulbs from Nepal. In addition, F. cirrhosa is registered as an active ingredient in traditional herbal medicinal preparations in Australia, Canada, Hong Kong SAR, Malaysia, Republic of Korea, Singapore and Taiwan. There is also an export trade in F. cirrhosa to Europe. Assessing how much F. cirrhosa is traded is complex, however, due to a "look-alike" challenge, as nine Chinese Fritillaria species are traded in Europe (Fritillaria cirrhosa, F. delavayi, F. hupehensis, F. pallidiflora, F. przewalskii, F. thunbergii, F. unibracteata, F. ussuriensis and F. walujewii).
AIMS OF THE STUDY: The aims of this review were to assess the scale of the global trade in F. cirrhosa, and to synthesise studies of the impacts of wild harvest on F. cirrhosa populations and on the extent of emerging cultivation initiatives as an alternative to wild harvest.
METHODS: Firstly, we reviewed published information on studies on impacts of wild F. cirrhosa harvest from across the geographic range of this species. Secondly, global trade data for F. cirrhosa were analysed.
RESULTS: The principal demand for F. cirrhosa bulbs is in China, where hundreds of different companies produce Fritillaria preparations. Trade data also show that in 2013, China exported over 44 tonnes of F. cirrhosa bulbs to Taiwan and 26.7 tonnes to the Republic of Korea. Extensive commercial use and limited wild stocks result in a high price (2000 - 3800 CNY per kg (around US$ 303 -560 per kg in 2017)) for F. cirrhosa bulbs. Prices of cultivated Fritillaria bulbs are much lower (600-680 CNY per kg in 2017) than wild harvested bulbs. But due to very specific growth requirements of F. cirrhosa, cultivation is not yet able to meet total demand. The consequence is continued exploitation of wild stocks. At the same time, however, an increasing proportion of the demand is met by cultivation of alternative Fritillaria species that are easier to grow than F. cirrhosa. The air-dry mass of F. cirrhosa bulbs varies between 0.0917 and 0.1116 g per bulb. This represents 8960 - 10,900 bulbs/kg or 8.9 - 10.9 million bulbs per tonne. Current demand therefore represents billions of bulbs per year.
CONCLUSIONS: Demand for F. cirrhosa bulbs, particularly from China, makes this species one of the most intensively harvested alpine Himalayan medicinal bulbs. Although F. cirrhosa is listed as a Class III protected species in China, billions of these tiny, wild harvested bulbs are sold per year. Due to demand exceeding supply, the price of F. cirrhosa bulbs has increased dramatically. Between 2002 and 2017, for example, the price of wild harvested F. cirrhosa bulbs increased over nine-fold, from the equivalent of US$60 in 2002 to US$560 per kg in 2017. To date, cultivation has been unable to meet the entire market demand for F. cirrhosa bulbs, although other Fritillaria species are successfully cultivated on a larger scale.
Potential of Producing Flavonoids Using Cyanobacteria As a Sustainable Chassis

Jin H, Wang Y, Zhao P, Wang L, Zhang S, Meng D, et al.

J Agric Food Chem, 2021 Oct 27;69(42):12385-12401.
PMID: 34649432 DOI: 10.1021/acs.jafc.1c04632

Numerous plant secondary metabolites have remarkable impacts on both food supplements and pharmaceuticals for human health improvement. However, higher plants can only generate small amounts of these chemicals with specific temporal and spatial arrangements, which are unable to satisfy the expanding market demands. Cyanobacteria can directly utilize CO2, light energy, and inorganic nutrients to synthesize versatile plant-specific photosynthetic intermediates and organic compounds in large-scale photobioreactors with outstanding economic merit. Thus, they have been rapidly developed as a "green" chassis for the synthesis of bioproducts. Flavonoids, chemical compounds based on aromatic amino acids, are considered to be indispensable components in a variety of nutraceutical, pharmaceutical, and cosmetic applications. In contrast to heterotrophic metabolic engineering pioneers, such as yeast and Escherichia coli, information about the biosynthesis flavonoids and their derivatives is less comprehensive than that of their photosynthetic counterparts. Here, we review both benefits and challenges to promote cyanobacterial cell factories for flavonoid biosynthesis. With increasing concerns about global environmental issues and food security, we are confident that energy self-supporting cyanobacteria will attract increasing attention for the generation of different kinds of bioproducts. We hope that the work presented here will serve as an index and encourage more scientists to join in the relevant research area.