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Objective: A method for the determination of 7 synthetic colorants in freshly prepared beverages by high performance liquid chromatography dual （HPLC） wavelength method with automatic solid phase extraction was established. Methods: Extraction conditions: The sample was extracted 2 times with pure water, and then the supernatant combined after centrifugation. The pH of the supernatant was adjusted to 3~4. After activation by an automatic solid-phase extraction device, loading, rinsing, and elution of the sample were carried out on the Poly-sery synthetic colorant solid-phase extraction column. The eluent was concentrated to 200 μL by nitrogen blowing, and then fixed to 1.0 mL with 50% mobile phase A+50% mobile phase B. Instrument conditions: The column was C18 column. The mobile phase was 20 mmol/L ammonium acetate-methanol, gradient elution. The flow rate was 1.0 mL/min. The injection volume was 10 μL. The detection wavelength were 254 nm and 628 nm. Results: The correlation coefficient of each substance in the range of 0.5～50 μg/mL was greater than 0.999 9, the detection limit of the method was 0.023～0.179 mg/kg, the quantitative limit was 0.078～0.598 mg/kg, the standard recovery was 92.4%～96.8%, and the relative standard deviation （RSD） was 1.2%～4.2%. Conclusion: This method has low consumption of toxic reagents, simple operation steps, high degree of automation, good recovery and repeatability, and it is suitable for the determination of large quantities of samples.

To provide teaching assistance to secondary school mathematics teachers in ethnic areas and improve the teaching effectiveness of mathematics courses, a hybrid teaching model based on deep learning algorithms is proposed. Convolutional neural networks and joint probability matrix decomposition are fused to design teaching resource recommendation methods, and hybrid teaching is carried out according to three stages: before, during, and after class. The overall mean of the questionnaire for the experimental class improved from 2.39 to 3.01, and the pass rate, merit rate, and mean score of mathematics scores increased by 13.79%, 9.02%, and 15.17 points, respectively. This method enables educational technology to be effective in mathematics curriculum and improve the quality and information of mathematics education in ethnic areas.

Intestinal ischemia‐reperfusion (IR) injury is a common gastrointestinal disease that induces severe intestinal dysfunction. Intestinal myenteric neurons participate in maintaining the intestinal function, which will be severely injured by IR. Macrophages are widely reported to be involved in the pathogenesis of organ IR injury, including intestine, which is activated by NLRP3 signaling. Lonicerin (LCR) is a natural extracted monomer with inhibitory efficacy against the NLRP3 pathway in macrophages. The present study aims to explore the potential protective function of LCR in intestinal IR injury. Myenteric neurons were extracted from mice. RAW 264.7 cells were stimulated by H/R with or without 10 μM and 30 μM LCR. Remarkable increased release of IL‐6, MCP‐1, and TNF‐α were observed in H/R treated RAW 264.7 cells, along with an upregulation of NLRP3, cleaved‐caspase‐1, IL‐1β, and EZH2, which were sharply repressed by LCR. Myenteric neurons were cultured with the supernatant collected from each group. Markedly decreased neuron number and shortened length of neuron axon were observed in the H/R group, which were signally reversed by LCR. RAW 264.7 cells were stimulated by H/R, followed by incubated with 30 μM LCR with or without pcDNA3.1‐EZH2. The inhibition of LCR on NLRP3 signaling in H/R treated RAW 264.7 cells was abolished by EZH2 overexpression. Furthermore, the impact of LCR on neuron number and neuron axon length in myenteric neurons in the H/R group was abated by EZH2 overexpression. Collectively, LCR alleviated intestinal myenteric neuron injury induced by H/R treated macrophages via downregulating EZH2. [ABSTRACT FROM AUTHOR]

This paper presents a multi-algorithm fusion model (StackingGroup) based on the Stacking ensemble learning framework to address the variable selection problem in high-dimensional group structure data. The proposed algorithm takes into account the differences in data observation and training principles of different algorithms. It leverages the strengths of each model and incorporates Stacking ensemble learning with multiple group structure regularization methods. The main approach involves dividing the data set into K parts on average, using more than 10 algorithms as basic learning models, and selecting the base learner based on low correlation, strong prediction ability, and small model error. Finally, we selected the grSubset + grLasso, grLasso, and grSCAD algorithms as the base learners for the Stacking algorithm. The Lasso algorithm was used as the meta-learner to create a comprehensive algorithm called StackingGroup. This algorithm is designed to handle high-dimensional group structure data. Simulation experiments showed that the proposed method outperformed other R2, RMSE, and MAE prediction methods. Lastly, we applied the proposed algorithm to investigate the risk factors of low birth weight in infants and young children. The final results demonstrate that the proposed method achieves a mean absolute error (MAE) of 0.508 and a root mean square error (RMSE) of 0.668. The obtained values are smaller compared to those obtained from a single model, indicating that the proposed method surpasses other algorithms in terms of prediction accuracy. [ABSTRACT FROM AUTHOR]

A simple, sensitive, and accurate stability-indicating analytical method has been developed and validated using ultra high performance liquid chromatography. The developed method is used to evaluate the related substances of eplerenone (EP). The degradation behavior of EP under stress conditions was determined, and the major degradants were identified by ultra high performance liquid chromatography with tandem mass spectrometry. The chromatographic conditions were optimized using an impurity-spiked solution, and the samples, generated from forced degradation studies. The resolution of EP, its potential impurities, and its degradation products was performed on a Waters UPLC BEH C18 column (50 × 2.1 mm, 1.7 μm) by linear gradient elution using a mobile phase consisting of 10 mmol/L ammonium acetate adjusted to pH 4.5, methanol and acetonitrile. A photo-diode array detector set at 245 nm was used for detection. The flow rate was set at 0.3 mL/min. The procedure had good specificity, linearity (0.02-3.14 μg/mL), recovery (96.1-103.9%), limit of detection (0.01-0.02 μg/mL), limit of quantitation (0.03-0.05 μg/mL), and robustness. The correction factors of the process-related substances were calculated. [ABSTRACT FROM AUTHOR]

Abstract: In this work, the upgrading reactions of high-boiling fraction (HBF) of bio-oil were carried out over a series of supported mono- and bi-metallic catalysts under the supercritical methanol condition. During these reactions, esterification and cracking (alcoholysis and hydrocracking) were the two dominant processes. PtNi/MgO exhibited good performance, and gave a high yield (72.4wt.%) of refined oil. The acid–base properties of the supports have an important effect on the coke deposition on the catalyst surface. The acidic catalysts gave the somewhat lower product yields, but tended to inhibit coking reaction. This would improve the life of the catalysts in the practical applications. The refined oil is believed to be a potential substitute or partial substitute for the fossil transportation fuel. [Copyright &y& Elsevier]

Abstract: In this work, the low-boiling fraction (LBF) of bio-oil was used as feed stock. LBF is a very complex mixture, and the three groups in LBF: acids, aldehydes and phenols, are primarily responsible for deterioration in the quality. The upgrading reactions were carried out over Pt/Al2(SiO3)3, Pt/C or Pt/MgO in supercritical methanol. It is demonstrated that supercritical condition can greatly facilitate the esterification process, and after 6h reaction, all the acids can be converted into esters even without adding any catalyst. The total amount of the three groups left in products was much less exhibited on Pt supported on active carbon and MgO in the presence of hydrogen. By investigating the model reactions, the relations between the representative compounds and major products were identified, and the conversion scheme of the upgrading reactions is proposed. [Copyright &y& Elsevier]

Patients with severe intestinal injury caused by trauma and malignant intestinal diseases require an artificial anus to be established through enterostomy to replace the original perineal anus for defecation. Although enterostomy has brought a new way of defecation to patients, the nursing requirements for an intestinal stoma after enterostomy are high. If complications arise from improper postoperative wound care, the quality of life of patients will be seriously reduced, and the psychological burden will be aggravated. This study compared the nursing effect of wet dressings and traditional dry dressings on patients undergoing enterostomy. Results showed that compared to patients using dry dressings, patients who used wet dressings had significantly lower postoperative dressing change frequency and complication rate, less pain during dressing change, and shorter hospital stays and intestinal stoma incision healing time. This suggests that wet dressings can promote wound healing in patients with enterostomy. In addition, it was found that compared to patients using dry dressings, the postoperative sleep quality, mood score, and quality of life of patients using wet dressings were significantly better. Evaluation of patient care comfort and satisfaction revealed that patients who used wet dressings felt significantly more comfortable and satisfied with their care than those who used dry dressings. Therefore, this study argues that wet dressings can facilitate the wound healing of the intestinal stoma in patients with enterostomy more than dry dressings, and better alleviate the bad moods and improve the quality of life of patients. Wet dressing can be used as a preferred nursing method for patients undergoing enterostomy., Competing Interests: None., (AJTR Copyright © 2021.)

Background: There has been a considerable focus on the changes of functional connections between brain regions in patients with type 2 diabetes mellitus (T2DM) by previous resting-state functional magnetic resonance imaging (rs-fMRI) studies. However, little is known about the function of brain information integration between the two hemispheres of the brain. This study explores differences in interhemispheric coordination between T2DM patients and normal control (NC) subjects using the voxel-mirrored homotopic connectivity (VMHC) method. We also assess whether differences in VMHC were relevant to cognitive dysfunction in T2DM patients., Methods: Sixty-nine T2DM patients and 69 NC subjects were enrolled (matched for age, sex and education level). All participants underwent cognitive assessments. VMHC between brain regions was obtained by rs-fMRI analysis. Partial correlation analysis (after controlling for age, sex and education level) was used to explore the correlation between VMHC value and neuropsychological tests., Results: Compared with NC subjects, T2DM patients exhibited significantly lower VMHC in the medial orbitofrontal gyrus cortex (mOFC), anterior cingulate gyrus, inferior parietal lobe, superior and middle temporal gyrus (MTG), middle occipital gyrus, and superior occipital gyrus. Moreover, after applying Bonferroni correction, the Montreal Cognitive Assessment (MoCA) score and VMHC value for the MTG were significantly positively correlated in T2DM patients. In contrast, T2DM patients exhibited higher VMHC in the cerebellum posterior lobe and tonsil and inferior temporal gyrus than the NCs., Conclusions: Our study indicates that functional coordination between homotopic brain regions is generally impaired in T2DM patients. In brain regions with decreased VMHC in the default mode network (DMN), MTG impairment could serve as a critical node for T2DM-related cognitive dysfunction. Furthermore, the increased VMHC observed in the cerebellum and inferior temporal gyrus might indicate a functional coordination mechanism.