ABSTRACT
The establishment of a heterojunction is a crucial strategy to design highly effective nonnoble metal nanocatalysts for the photocatalytic nitrogen reduction reaction (PNRR). Heteropoly blues (r-POMs) can act as electron-transfer mediators in PNRR, but its agglomeration limits the further promotion of PNRR productivity. In this work, we construct a protonation-modified surface of N-vacancy g-C3N4 (HV-C3N4), achieving the high dispersion of r-POMs via the surface modification strategy. Enlightened by the synergy effect of the nitrogenase, r-POMs were anchored onto HV-C3N4 nanosheets through an electrostatic self-assembly method for preparing r-POMs-based protonation-defective graphitic carbonitride (HV-C3N4/r-POMs). As an electron donor, r-PW12 can match with the energy level of HV-C3N4 to build a heterojunction. The electron redistribution of the heterojunction facilitates the optimization of the electronic structure for enhancing the performance of PNRR. HV-C3N4/r-PW12 exhibits the best PNRR efficiency of 171.4 µmol L-1 h-1, which is boosted by 94.39% (HV-C3N4) and 86.98% (r-PW12). The isotope 15NH4+ experiment proves that ammonia is derived from N2, not carbon nitride. This study opens up a crucial view to achieve the high dispersion of r-POMs nanoparticles and develop high-efficiency nonnoble metal photocatalysts for the PNRR.
ABSTRACT
BACKGROUND: Noninvasive biomarkers have been developed to predict hepatitis B virus (HBV) related fibrosis owing to the significant limitations of liver biopsy. Both serum biomarkers and imaging techniques have shown promising results and may improve the evaluation of liver fibrosis. However, most of the previous studies focused on the diagnostic effects of various imaging techniques on fibrosis in all chronic liver diseases. AIM: To compare the performance of common imaging methods and serum biomarkers for prediction of significant fibrosis caused only by HBV infection. METHODS: A systematic review was conducted on the records available in PubMed, EMBASE, and the Cochrane Library electronic databases until December 2018. We systematically assessed the effectiveness of two serum biomarkers and three imagine techniques in predicting significant fibrosis solely caused by HBV infection. The serum biomarkers included aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis index based on the 4 factors (FIB-4). The three imaging techniques included acoustic radiation force impulse (ARFI), FibroScan, and magnetic resonance elastography (MRE). Three parameters, the area under the summary receiver operating characteristic curve (AUSROC), the summary diagnostic odds ratio, and the summary sensitivity and specificity, were used to examine the accuracy of all tests for liver fibrosis. RESULTS: Out of 2831 articles evaluated for eligibility, 204 satisfied the predetermined inclusion criteria for this current meta-analysis. Eventually, our final data contained 81 studies. The AUSROCs of serum biomarkers of APRI and FIB-4 were both 0.75. For imaging techniques (ARFI, FibroScan, and MRE), the areas were 0.89, 0.83, and 0.97, respectively. The heterogeneities of ARFI and FibroScan were statistically significant (I 2 > 50%). The publication bias was not observed in any of the serum biomarkers or imaging methods. CONCLUSION: These five methods have attained an acceptable level of diagnostic accuracy. Imaging techniques, MRE in particular, demonstrate significant advantages in accurately predicting HBV-related significant fibrosis, while serum biomarkers are admissible methods.
ABSTRACT
Noninvasive biomarkers have been developed to predict hepatitis B virus (HBV)-related fibrosis owing to the significant limitations of liver biopsy. Those biomarkers were initially derived from evaluation of hepatitis C virus (HCV)-related fibrosis, and their accuracy among HBV-infected patients was under constant debate. A systematic review was conducted on records in PubMed, EMBASE and the Cochrane Library electronic databases, up until April 1st, 2013, in order to systematically assess the effectiveness and accuracy of these biomarkers for predicting HBV-related fibrosis. The questionnaire for quality assessment of diagnostic accuracy studies (QUADAS) was used. Out of 115 articles evaluated for eligibility, 79 studies satisfied the pre-determined inclusion criteria for meta-analysis. Eventually, our final data set for the meta-analysis contained 30 studies. The areas under the SROC curve for APRI, FIB-4, and FibroTest of significant fibrosis were 0.77, 0.75, and 0.84, respectively. For cirrhosis, the areas under the SROC curve for APRI, FIB-4 and FibroTest were 0.75, 0.87, and 0.90, respectively. The heterogeneity of FIB-4 and FibroTest were not statistically significant. The heterogeneity of APRI for detecting significant fibrosis was affected by median age (Pâ=â0.0211), and for cirrhosis was affected by etiology (Pâ=â0.0159). Based on the analysis we claim that FibroTest has excellent diagnostic accuracy for identification of HBV-related significant fibrosis and cirrhosis. FIB-4 has modest benefits and may be suitable for wider scope implementation.
