Modeling mechanism and extension of GM (1,1)

Firstly, the research progress of grey model GM （1,1） is summarized, which is divided into three development stages： assimilation, alienation and melting stages. Then, the matrix analysis theory is used to study the modeling mechanism of GM （1,1）, which decomposes the modeling data matrix into raw data transformation matrix, accumulated generating operation matrix and background value selection matrix. The changes of these three matrices are the essential reasons affecting the modeling and the accuracy of GM （1,1）. Finally, the paper proposes a generalization grey model GGM （1,1）, which is a extended form of GM （1,1） and also a unified form of model GM （1,1）, model GM （1,1,α）, stage grey model, hopping grey model, generalized accumulated model, strengthening operator model, weakening operator model and unequal interval model. And the theory and practical significance of the extended model is analyzed.

Cobalt phthalocyanine-based conjugated polymer as efficient and exclusive electrocatalyst for CO_(2) reduction to ethanol

Electrocatalytic conversion of carbon dioxide to high value-added chemicals is a promising method for solving the energy crisis and global warming.Electrochemical active metal-containing conjugated polymers have been widely studied for heterogeneous carbon dioxide reduction.In the present contribution,we designed and synthesized a stable cobalt phthalocyanine-based conjugated polymer,named CoPPc-TFPPy-CP,and also explored its electro-catalytic application in carbon dioxide reduction to liquid products in an aqueous solution.In the catalyst,cobalt phthalocyanine acts as building blocks connected with 1,3,6,8-tetrakis(4-formyl phenyl)pyrenes via imine-linkages,leading to mesoporous formation polymers with the pore size centered at 4.1nm.And the central co-balt atoms shifted to a higher oxidation state after condensation.With these chemical and structural natures,the catalyst displayed a remarkable electrocatalytic CO_(2) reduction performance with an ethanol Faradaic efficiency of 43.25%at-1.0V vs RHE.While at the same time,the electrochemical reduction process catalyzed by cobalt phthalocyanine produced only carbon monoxide and hydrogen.To the best of our knowledge,CoPPc-TFPPy-CP is the first example among organic polymers and metal-organic frameworks that produces ethanol from CO_(2) with a remarkable selectivity.

Injectable thermo-responsive nano-hydrogel loading triptolide for the anti-breast cancer enhancement via localized treatment based on “two strikes” effects

The clinical application of triptolide(TPL)in tumor therapy has been greatly limited by its toxicity and inefficient delivery.Herein,a localized and sustained-release thermo-sensitive hydrogel was developed for the intra-tumor administration of TPL.Based on the amphiphilic structure of poly(N-isopropylacrylamide-co-acrylic acid)-g-F68 copolymer,it was able to form nano-micelles to efficiently encapsulate TPL,and then turn into a hydrogel at 37C.TPL@nano-gel exhibited a sustained drug release profile in vitro and a stronger anticancer effect caused by"two strikes".The"first strike"was its enhanced cytotoxicity compared to free TPL,due to the enhanced pro-apoptosis effect observed in both MDA-MB-231 and MCF-7 cells caused by the regulation of endogenous mitochondrial pathways.Furthermore,TPL@nano-gel exhibited a"second-strike"through its anti-angiogenesis capabilities mediated through VEGFR-2 signaling inhibition.As expected,after intra-tumoral injection at a 0.45 mg/kg TPL-equivalent dose three times over 14 days in 4 T1 tumor-bearing mice,TPL@nano-gel led to lower systemic toxicity and higher antitumor efficacy compared to multiple injections of TPL.In this regard,these findings indicate that this injectable thermo-responsive hydrogel carries great potential for TPL as a safe and effective cancer therapy.

Alterations in gut microbiota and metabolites associated with altitude-induced cardiac hypertrophy in rats during hypobaric hypoxia challenge

The gut microbiota is involved in host responses to high altitude.However,the dynamics of intestinal microecology and their association with altitude-related illness are poorly understood.Here,we used a rat model of hypobaric hypoxia challenge to mimic plateau exposure and monitored the gut microbiome,short-chain fatty acids(SCFAs),and bile acids(BAs)over 28 d.We identified weight loss,polycythemia,and pathological cardiac hypertrophy in hypoxic rats,accompanied by a large compositional shift in the gut microbiota,which is mainly driven by the bacterial families of Prevotellaceae,Porphyromonadaceae,and Streptococcaceae.The aberrant gut microbiota was characterized by increased abundance of the Parabacteroides,Alistipes,and Lactococcus genera and a larger Bacteroides to Prevotella ratio.Trans-omics analyses showed that the gut microbiome was significantly correlated with the metabolic abnormalities of SCFAs and BAs in feces,suggesting an interaction network remodeling of the microbiome-metabolome after the hypobaric hypoxia challenge.Interestingly,the transplantation of fecal microbiota significantly increased the diversity of the gut microbiota,partially inhibited the increased abundance of the Bacteroides and Alistipes genera,restored the decrease of plasma propionate,and moderately ameliorated cardiac hypertrophy in hypoxic rats.Our results provide an insight into the longitudinal changes in intestinal microecology during the hypobaric hypoxia challenge.Abnormalities in the gut microbiota and microbial metabolites contribute to the development of high-altitude heart disease in rats.

Rapid determination of pesticide residues in Chinese materia medica using QuEChERS sample preparation followed by gas chromatography-mass spectrometry

Pesticide residue analysis plays an important role in the quality control of Chinese materia medica.This paper reports the development and validation of an analytical method for the quantitative determination of the residues of 39 pesticides in 12 different matrices of Chinese materia medica.Sample preparation utilized the QuEChERS method with acetonitrile:1% aqueous acetic acid(9:1,v/v)as extraction solvent followed by sample clean-up by dispersive solid phase extraction using primary secondary amine sorbent and graphitized carbon black.Extracts were then analysed by gas chromatography coupled with electron impact mass spectrometry in the selected ion monitoring mode.Limit of detection(LOD)and limit of quantitation(LOQ)values were in the ranges 0.5-50 ng/g and 1-100 ng/g,respectively.The recoveries of the 39 pesticides were in the range 75-112% with precision(as relative standard deviation,RSD)<15%.The results show that the modified QuEChERS method allows rapid and sensitive analysis of multiple pesticide residues in Chinese materia medica.

Synthesis of Cs_(2.5)H_(0.5)PW_(12)O_(40)/TiO_(2) Nanocomposites with Dominant TiO_(2){001}Facets and Related Photocatalytic Properties

TiO_(2)nanosheets with dominant{001}facets,coupled with Cs_(2.5)H_(0.5)PW_(12)O_(40),were successfully synthesized by a one-step hydrothermal reaction.The photocatalytic activity of nanocatalysts was evaluated by the degradation of Rhodamine B under UV light irradiation.The results showed that both the addition of Cs_(2.5)H_(0.5)PW_(12)O_(40)and the exposed{001}facets of TiO_(2)have a positive effect on the photocatalytic activity.The improved photoactivity of nanocomposites in comparison with that of TiO_(2)nanosheets could be attributed to the synergistic effect between Cs_(2.5)H_(0.5)PW_(12)O_(40)and TiO_(2)which facilitates the separation of photo-induced hole-electron pairs.

Synthesis and orientational assemblies of MgO nanosheets with exposed(111) facets

MgO nanosheets with exposed（111） facets were obtained through the preparation of Mg（OH）2 precursor by a hydrothermal method in the presence of oleylamine and subsequent calcination in air. The different preferred orientational assemblies of Mg O nanosheets, achieved by adjusting the polarity of dispersing solvents（ethanol and cyclohexane） during the sample preparation, show different structural and spectral features.