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In this study, deep eutectic solvents were used for the extraction of flavonoids from Spatholobus suberectus. The extraction effect was measured using UV spectrophotometer and found that the deep eutectic solvent consisting of choline chloride and triethylene glycol (1:2) was the best extraction. The solvent water content (%), liquid-to-material ratio (v/m), and extraction temperature (K) were optimized using the central composite bounded design response surface method in a single-factor experiment. The results showed that the extraction yield of chickweed flavonoids reached 96.01 (mg/g) at a liquid-to-material ratio of 39:1, a water content of 43% in DESs and an extraction temperature of 336.6 K for 5 min, which was 2.85 and 4.12 times higher than that of the control group (90 min extraction) using 60% ethanol and water, respectively. The antioxidant activity of the extracts was evaluated using 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazin-1-yl (DPPH) and it was found that the extracts inhibited DPPH by 89.765%, indicating the high content of flavonoids extracted. This study provides an idea for the extraction of functional components of biological origin.

The Au6 cluster can produce a variety of adsorption conformation complexes with carbon materials by physical or chemical adsorption. Such complexes are potential molecular switches. The adsorption behavior of the newly reported pure carbon ring cyclo [18] carbon (C18) with transition metal Au6 clusters is investigated based on density functional theory (DFT). The results show that the complexes are chemically bonded and have two stable conformations. An applied electric field can achieve the interconversion of the two dominant conformations. Various wave function analyses showed that the formation of the complexes reduced the delocalization of the carbon ring π electrons, and there were significant differences in the electron transfer modes and infrared spectra of the two stable conformations. The formation of complexes reduces the intrinsic reactivity of both fragments and can play a role in stabilizing both C18 and Au6 clusters. This study has positive implications for revealing the microscopic nature of the chemical processes between metals and C18 in the transition region.

Purpose BAT-26 is one of the representative markers for microsatellite instability evaluation and presents different polymorphisms in different ethnic populations. The current knowledge of its comparative polymorphism between healthy individuals and cancer patients in the Chinese population is insufficient. This study aims to analyze germline polymorphic variations of BAT-26 between healthy individuals and cancer patients in Chinese from Jiangsu province and the associated cancer risk implications. Methods The various BAT-26 alleles and their percentages in cervical cells from 500 healthy women were assessed by direct sequencing. Twenty of these samples were also analyzed by fragment analysis. BAT-26 of blood DNA from 24 healthy individuals and 247 cancer patients was analyzed by fragment analysis. Results Compared with the sequencing results, 122.6-122.9 bp, 123.4-123.8 bp and 124.1-124.8 bp corresponded to the A25, A26 and A27 alleles, respectively. The 524 healthy individuals showed 4.58%, 92.18% and 3.24% of A25, A26 and A27, respectively. The variant alleles A18, A24, A28, A29 and A32 were only found in cancer patients, accounting for 0.81%, 0.40%, 0.40%, 0.40% and 0.40%, respectively; the A25, A26 and A27 alleles in cancer patients accounted for 6.48%, 77.33% and 13.77%. Conclusions Healthy individuals had a stable BAT-26 profile within the quasimonomorphic variation range (QMVR), but cancer patients harbored variant alleles outside QMVR and showed a trend from quasimonomorph to polymonomorph, suggesting that variant alleles of BAT-26 in germline cells may be regarded as a potential marker of higher cancer risk in the Chinese population from Jiangsu province.

Various highly dispersed Mo supported catalysts with various carriers were prepared for deep hydrodesulphurization of diesel. The carriers included a high surface area and large pore volume γ-Al2O3, two types of meso-microporous composite molecular sieves prepared by incipient-wetness impregnation method. A new mesoporous MoSiOx catalyst synthesized with in situ composite method was also studied. The hydrodesulphurization experiments were carried out in a micro-reactor over different catalysts including Mo supported series and a commercial catalyst. Spectroscopic techniques (FT-IR and UV–vis DRS) were utilized to determine the structure of MoOx species. The catalyst characterizations of BET, XRD, FT-IR, UV–vis DRS and FTIR pyridine adsorption indicated that the existences of metal active component of Mo in the catalysts were highly dispersed nano MoO3 clusters and the Mo series catalysts had high surface areas and plenty of large pores which were propitious to the diffusions of reactant and product molecules. CatNiMo exhibited the highest B/L acidity ratio and higher total concentration of Bronsted acid sites and Lewis acid sites, and its HDS activity also gave the highest in this study to produce a sulphur-free diesel, which was verified by the sulphur content in products analyzed by GC–MS methods.

A behavior-based telecom customer churn prediction system is presented in this paper. Unlike conventional churn prediction methods, which use customer demographics, contractual data, customer service logs, call-details, complaint data, bill and payment as inputs and churn as target output, only customer service usage information is included in this system to predict customer churn using a clustering algorithm. It can solve the problems which traditional methods have to face, such as missing or non-reliable data and the correlation among inputs. This study provides a new way to solve traditional churn prediction problems.

The limitations of traditional examination modes to inspire active learning indicates the need for more a reasonable or comprehensive examination form in higher education. This article analyzes the advantages and disadvantages of the traditional examination method; while at the same time, providing a brief look at some of the other forms of assessment. A comprehensive examination mode is established to assess the teaching and learning outcomes in a Analytical Chemistry course. It provides a combination of varieties of exam methods. This more comprehensive mode focuses more on the concept of “student centered” learning, and serves the teaching purpose better.

Databases are used in many facets of society by an array of people. While the obvious platform for most database applications has been a relational Data Base management Systems (DBMS), the object-oriented programming languages which are widely used in software development are not well matched to their development. In many ways it is obvious that there is an ‘object-relational’ impedance and mismatch. There are currently only a few courses about object-oriented database development in universities. In this paper, an object-oriented database named db4o is introduced as a viable alternative to traditional database development methods. It is now used in our newly developed object-oriented database course. With a visual object management viewer, db4o helps students to understand basic object-oriented database conception and to grasp programming with the object-oriented programming language.