Optimal algorithms for the online time series search problem

AbstractIn the problem of online time series search introduced by El-Yaniv et al. (2001) [1], a player observes prices one by one over time and shall select exactly one of the prices on its arrival without the knowledge of future prices, aiming to maximize the selected price. In this paper, we extend the problem by introducing profit function. Considering two cases where the search duration is either known or unknown beforehand, we propose two optimal deterministic algorithms respectively. The models and results in this paper generalize those of El-Yaniv et al. (2001) [1]

Gastroprotective effect of the root extract of Alpinia officinarum Hance (Zingiberoside) against acute indomethacin-induced gastric injuries in rats: Involvement of H+/K+-ATPase and prostaglandin E receptors

Purpose: To investigate the protective effects of Alpinia officinarum root ethanol extract (AOE) and galangin against acute indomethacin-induced injury on rat gastric mucosaMethods: Sprague-Dawley rats were daily treated with bismuth potassium citrate (0.08 g/kg), AOE at doses of 0.09, 0.18 and 0.36 g/kg; and galangin (0.2 g/kg) for 15 days. Then, gastric injury on rats was induced by intragastric administration of indomethacin (30 mg/kg). Blood flow and thickness of gastric mucosa were determined using neutral red clearance test and Alcian blue staining. The activity of H+/K+-ATPase was assayed using a biochemical kit. Prostaglandin E receptor expressions were assayed by western blotting.Results: High doses of ethanol extract of Alpinia officinarum root significantly inhibited H+/K+-ATPase activity by 8.12 % (p < 0.01), increased gastric mucosal blood flow (p < 0.001), enhanced mucus thickness (p < 0.05), and elevated the activities of prostaglandin E receptors 1 and 4 (p < 0.05).Galangin significantly inhibited H+/K+-ATPase activity by 4.82 % (p < 0.05) and increased gastric mucosal blood flow (p < 0.01).Conclusion: The ethanol extract of Alpinia officinarum root attenuates indomethacin-induced gastric injury by reinforcing gastric mucosal barrier and inhibiting excessive gastric acid secretion. Thus, the extract can be potentially developed for management of gastric injuries. Keywords: Galangin, Gastric mucosal barrier, Gastric acid, Prostaglandin, Indomethaci

Isolation and identification of two galangin metabolites from rat urine and determination of their in vitro hypolipidemic activity

Purpose: To investigate the lipid-lowering activity of two metabolites of galangin, namely, galangin-3-O-β-D-glucuronic acid (GG-1) and galangin-7-O-β-D-glucuronic acid (GG-2).Methods: Female Sprague-Dawley rats were orally administered with galangin. The two metabolites of galangin were isolated from urine sample and purified using Sephadex LH-20 and semi-preparative high performance liquid chromatography (HPLC). The structures of the metabolites were identified by analyzing spectroscopic data. Hypolipidemic activity was evaluated in HepG2 cells. The down- or upregulation of lipogenic genes was detected using real-time quantitative polymerase chain reaction (qPCR).Results: Both metabolites of galangin showed hypolipidemic activity. These  activities are closely associated with the down-regulation of lipogenic genes such as SREBP-1a, SREBP-1c, and SREBP-2 transcription factors, and the downstream genes such as FAS, ACC, and HMGR were revealed by realtime qPCR data.Conclusion: The results show that both metabolites possess better lipid-lowering activities than galangin. These hypolipidemic activities are closely associated with inhibiting key genes or proteins that regulated the biosynthesis of both cholesterol and triglycerides.Keywords: Galangin, Galangin-3-O-β-D-glucuronic acid, Galangin-7-O-β- D-glucuronic acid, Hypolipidemic, Lipogenic genes, Metabolite

Study on the Effect of Regional Water Pollution—Take Huaxi River in Chongqing as an Example

Water pollution management plays a crucial role in China’s ecological environment development. It has evolved from being solely the responsibility of the government to a collaborative effort involving multiple entities. This paper presents findings from a field survey conducted around the collaborative capacity and effectiveness of wastewater treatment in Huaxi River, Chongqing. The study collected 427 valid questionnaires and employed SPSS26.0 software and AMOS24.0 software, utilizing structural equation modelling and regression analysis to verify the relationship between the variables. The results highlight that synergy mechanism acts as a mediating variable between synergy capability and synergy governance effect, underscoring the role of mechanism in the relationship between capability and governance effect. The conclusion emphasizes the importance of enhancing synergistic capacity and synergistic mechanism to effectively promote synergistic governance effect in the water pollution management of Huaxi River in Chongqing. This can be achieved by improving the abilities of multiple stakeholders in managing water pollution, enhancing cooperation among parties, and encouraging participation of social organizations, the public, and enterprises in the management process to achieve sustainable development of ecological civilization

Inkjet printing of polyimide insulators for the 3D printing of dielectric materials for microelectronic applications

In this article, we report the first continuous fabrication of inkjet-printed polyimide films, which were used as insulating layers for the production of capacitors. The polyimide ink was prepared from its precursor poly(amic) acid, and directly printed on to a hot substrate (at around 160 °C) to initialize a rapid thermal imidization. By carefully adjusting the substrate temperature, droplet spacing, droplet velocity, and other printing parameters, polyimide films with good surface morphologies were printed between two conducting layers to fabricate capacitors. In this work, the highest capacitance value, 2.82 ± 0.64 nF, was achieved by capacitors (10 mm × 10 mm) with polyimide insulating layers thinner than 1 μm, suggesting that the polyimide inkjet printing approach is an efficient way for producing dielectric components of microelectronic devices. © 2016 The Authors Journal of Applied Polymer Science Published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43361