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Caffeoylquinic acids (CQAs) are main constituents in many herbal medicines with various biological and pharmacological effects. However, CQAs will degrade or isomerize when affected by temperature, pH, light, etc. In this study, high-performance liquid chromatography with photodiode array detection (HPLC-PDA) and high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was utilized to study the stability and degradation of CQAs (three mono-acyl CQAs and four di-acyl CQAs) under various ordinary storage conditions (involving different temperatures, solvents, and light irradiation). The results indicated that the stability of CQAs was mainly affected by temperature and light irradiation, while solvents did not affect it in any obvious way under the conditions studied. Mono-acyl CQAs were generally much more stable than di-acyl CQAs under the same conditions. Meanwhile, the chemical structures of 30 degradation products were also characterized by HPLC-MSn, inferring that isomerization, methylation, and hydrolysis were three major degradation pathways. The result provides a meaningful clue for the storage conditions of CQAs standard substances and samples. [ABSTRACT FROM AUTHOR]

The classical Adomian decomposition method (ADM) is implemented to solve a model of HIV infection of CD4+T cells. The results indicate that the approximate solution by using the ADM is the same as that by using the Laplace ADM, but it can be obtained in a more efficient way. We also use Padé approximation and Laplace transform as a posttreatment technique to obtain the result of the ADM. The advantage of the posttreatment is illustrated by numerical experiments. [ABSTRACT FROM AUTHOR]

According to the status of a low borehole gas drainage concentration in a soft seam, small drainage quantity and borehole easycollapsed and jammed, a high efficient gas drainage technology with fast full length screen pipe for the borehole protection in the soft seam was provided and the related key equipment was introduced. The application in a typical mine site of Huainan Mining Area showed that with the application of the technology, 75% of the borehole could be realized and completed within one hour, all boreholes could be completed with two hours and 85% of the borehole screen pipe could be set to 81% of the borehole depth. A gas drainage volume fraction of a single bore-hole could be increased from 30% to 60% and the pure gas drainage volume could be increased from 0.03 m³/min to 0.06 m³/min. The unit gas drainage volume fraction was increased about 120% and pure gas drainage quantity was increased from 2.0 m³/min to 4.2 m³/ min. The application of the technology could eliminate borehole failure caused by borehole collapsed, could highly improve the reliability of borehole gas pre-drainage and could ensure the gas pre-drainage effect of coal mining face. [ABSTRACT FROM AUTHOR]

The article highlights study which provided supplementary content in response to some of the researchers' valuable comments, which will aid the understanding. It discusses that the transparent reporting of a multivariable prediction model for individual prognosis of diagnosis (TRIPOD) Statement, providing a detailed framework for reporting prediction models, has guided work.

Based on the remote sensing images of algae, the present work analyzes the horizontal distribution characteristics of algal blooms in Chaohu Lake, China, which also reveals the frequency of algal blooms under different wind directions. Further, an unstructured-grid, three-dimensional finite-volume coastal ocean model (FVCOM) is applied to investigate the wind-induced currents and the transport process to explain the reason why algal blooms occur at the detected places. We first deduce the primary distribution of biomass from overlaid satellite images, and explain the formation mechanism by analyzing the pollution sources, and simulating the flow field and transportation process under prevailing wind over Chaohu Lake. And then, we consider the adjustment action of the wind on the corresponding day and develop a two-time scale approach to describe the whole formation process of algae horizontal distribution in Chaohu Lake. That is, on the longer time scale, i.e., during bloom season, prevailing wind determines the primary distribution of biomass by inducing the characteristic flow field; on the shorter time scale, i.e., on the day when bloom occurs, the wind force adjusts the primary distribution of biomass to form the final distribution of algal bloom. [ABSTRACT FROM AUTHOR]