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A novel electrochemical method has been developed, based on a covalent organic framework (COF) and reduced graphene oxide (rGO), to detect fentanyl and alfentanil. COF nanomaterials with chrysanthemum morphology obtained by solvothermal reaction contain rich active sites for electrochemical catalytic reaction, thus improving the detection performance of the designed sensor. Reduced graphene oxide improves the sensor's sensitivity due to enhanced electron transfer. Under optimized experimental conditions, the fabricated electrode presents a linear range of 0.02 to 7.26 μM for alfentanil and 0.1 to 6.54 μM for fentanyl, with detection limits of 6.7 nM and 33 nM, respectively. In addition, the sensor possesses excellent selectivity, outstanding reproducibility, and acceptable stability. The proposed sensor is feasible for the reliable monitoring of fentanyl and alfentanil in human serum samples, with acceptable reliability and high potential in real-world applications. Finally, the electrochemical characteristic fingerprint of fentanyl is investigated by studying the electrochemical behavior of alfentanil and fentanyl on the electrode surface. [ABSTRACT FROM AUTHOR]

In order to improve the effective guidance of martial arts movements, a decomposition method of martial arts movements based on image recognition is proposed. First of all, visual image target sampling of martial arts action is performed, and most of the noise background is eliminated through morphological gradient operation. Then, the contour edge of the human body is obtained, the contour edge of each frame of the video is extracted, and the accumulation is realized in the same image. Using accumulation, the edge image calculates the grid-based HOG to obtain the image action feature vector. Secondly, using the improved dynamic time warping theory combined with the characteristics of the angle change of each joint under the action time sequence, the joint change sequence among various martial arts movements can be identified in order to realize the decomposition process of martial arts actions based on image recognition. The experimental results show that the use of image recognition can effectively decompose martial arts movements. [ABSTRACT FROM AUTHOR]

Background: Human umbilical cord blood mesenchymal stem cells (HUCB‐MSCs) can exert a protective effect in rat models of acute liver failure (ALF). Vascular endothelial growth factor 165 (VEGF165) is the predominant VEGF isoform and possesses a strong pro‐angiogenic function. In the present study, HUCB‐MSC served as the gene delivery vehicle for the VEGF165 gene, and we explored the therapeutic effects of this system on ALF. Methods: HUCB‐MSCs were infected with an adenovirus expressing green fluorescent protein (GFP)‐VEFG fusion protein (Ad‐VEGF165) to overexpress VEGF165 or an adenovirus expressing GFP (Ad‐GFP) as control. The control and modified HUCB‐MSCs were then transplanted into ALF model rats. Liver function and liver pathological changes were assessed by biochemical tests and liver histology. Immunohistochemistry was carried out to determine the expression of, CD34, Ki67 and VEGF. Results: VEGF165 overexpression enhanced the multipotency of HUCB‐MSCs and promoted the homing and colonization of HUCB‐MSC in the liver tissues of ALF rats. Furthermore, although HUCB‐MSC transplantation ameliorated liver damage and promoted liver regeneration to some extent in ALF rats, Ad‐VEGF165‐HUCB‐MSC transplantation showed stronger therapeutic effects on ALF. Conclusions: In summary, transplantation of VEGF165‐modified HUCB‐MSCs exert stronger therapeutic effects on ALF than HUCB‐MSCs. The present study provides a novel therapeutic approach for ALF. [ABSTRACT FROM AUTHOR]

The purpose of our studies was to systematically assess the accuracy and clinical value of plasma calcitonin in patients with liver failure complicated with bacterial infection. In this study, we included prospective observational studies or randomized controlled trials on PCT. The quality of the studies was evaluated using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Heterogeneity, pooled diagnostic odds ratio (DOR), pooled sensitivity, pooled specificity, pooled positive likelihood ratio, pooled negative likelihood ratio, the area under the summary receiver operating characteristic curve (SROC), and metaregression analysis were performed using Stata16.0 software. Consequently, the studies revealed substantial heterogeneity (I2 = 96, 95% confidence interval (95% CI) = 94–99). The results of meta-analysis using random effect models suggested that the combined DOR was 10.67 (95% CI = 3.73–30.53). In addition, the threshold effect analysis showed that the threshold effect was 0.23 and the correlation coefficient was −0.48, indicating that there was no threshold effect. In the forest map, the DOR of each study and the combined DOR are not distributed along the same line, and Q = 2.2 × 1014, P ≤ 0.001. Furthermore, the metaregression analysis of PCT study design, bacterial infection site, and mean age displayed that the P values were >0.05. The combined sensitivity was 0.77 (95% CI = 0.54–0.90), the combined specificity was 0.76 (95% CI = 0.70–0.82), the combined positive likelihood ratio was 3.25 (95% CI = 2.33–4.52), the combined negative likelihood ratio was 0.30 (95% CI = 0.14–0.67), and the combined AUC was 0.80 (95% CI = 0.76–0.83). In conclusion, PCT has moderate diagnostic value for adult liver failure complicated with bacterial infection, and it is a better auxiliary diagnostic index for liver failure with bacterial infection. However, the results of procalcitonin must be carefully interpreted combined with medical history, physical examination, and microbiological assessment. [ABSTRACT FROM AUTHOR]

Scots pine (Pinus sylvestris L.) panels were modified with glutaraldehyde (GA) to various weight percent gains and subsequently coated with several commercial coatings. The drying rate and adhesion of the coatings on the modified wood were measured; the coated/modified woods were exposed outdoors to analyze how the wood modifications influence the coating deterioration. The results showed that GA modification caused an increase in the drying rate of the waterborne coatings, but had no influence on drying of tested solvent-borne coatings. GA-modification did not change the dry adhesion but reduced the wood strength in a pull-off test. Wet adhesion of waterborne coatings was improved, while that of the solvent-borne coatings tended to be somewhat reduced. During 22 months of outdoor weathering, the coated/modified samples exhibited lower moisture content than the coated/unmodified samples, but GA modification didn't contribute a substantially synergistic effect with surface coatings on resistance to weathering. [ABSTRACT FROM AUTHOR]

Radiata pine wood (W) was modified with acetic anhydride and glutaraldehyde (GA) resulting in WAc and WGA to various weight percent gains (WPGs), whereas in WAc the effect is due to grafting and in WGA, crosslinking. The heat of vaporization of bound water (BW) of the modified woods was studied by differential scanning calorimetry (DSC) and the mass loss (due to water loss) of the samples by thermogravimetry (TG). The temperature program was in both cases from 25 to 40°C with 10°C min−1. The adsorbed or condensed water in wood were observed via low-field nuclear magnetic resonance (LFNMR). At a comparable WPG level, the LFNMR analysis showed that the interaction of water with WGA was stronger than that with WAc. In both modified woods, a considerable reduction in the vaporization heat of BW was visible due to cell wall hydrophobization and bulking. The reduction of condensed water in micropores was lower for WGA than WAc, probably because BW needs more energy to evaporate from the crosslinked stiff WGA cell walls. [ABSTRACT FROM AUTHOR]