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The field of isomerization reactions for colloidal semiconductor magic-size clusters (MSCs) remains largely unexplored. Here, we show that MSCs isomerize via two fundamental pathways that are regulated by the acidity and amount of an incoming ligand, with CdTeSe as the model system. When MSC-399 isomerizes to MSC-422 at room temperature, the peak red-shift from 399 to 422 nm is continuous (pathway 1) and/or stepwise (pathway 2) as monitored in situ and in real time by optical absorption spectroscopy. We propose that pathway 1 is direct, with intracluster configuration changes and a relatively large energy barrier. Pathway 2 is indirect, assisted by the MSC precursor compounds (PCs), from MSC-399 to PC-399 to PC-422 to MSC-422. Pathway 1 is activated when PC-422 to MSC-422 is suppressed. Our findings unambiguously suggest that when a change occurs directly on a nanospecies, its absorption peak continuously shifts. The present study provides an in-depth understanding of the transformative behavior of MSCs via ligand-induced isomerization upon external chemical stimuli.

Colloidal semiconductor ternary CdTeS magic-size clusters (MSCs) have not been reported. Here, we present the first synthesis of CdTeS MSCs at room temperature and our understanding of the evolution pathway. The MSCs exhibit sharp optical absorption peaking at 381 nm and are labeled MSC-381. CdTeS MSC-381 evolves when pre-nucleation-stage samples of binary CdTe and CdS that do not contain quantum dots (QDs) are separately prepared and then mixed and incubated at room temperature. We propose that CdTeS MSC-381 evolves from its precursor compound (PC) via quasi-isomerization. Synchrotron-based small-angle X-ray scattering suggests that PCs/MSCs of CdTe and CdTeS are similar in sizes. We propose further that the CdTeS PC forms from the substitution reaction between the CdTe PC and the CdS monomer/fragment (Mo/Fr). The present study paves the way to the room-temperature evolution of ternary MSCs and provides an in-depth understanding of the PC to MSC transformation.

A rarely studied transformation in colloidal ternary magic-size clusters (MSCs) is addressed. We report the first observation of the transformation from ternary CdTeSe MSC-399 to MSC-422, which occurs at room temperature. These two MSC types display sharp optical absorption resonances at 399 and 422 nm, respectively, and are related in that they are quasi isomers, together with their counterpart precursor compounds (PCs). Binary CdTe and CdSe samples were prepared in the prenucleation stage also called the induction period (IP). After they were mixed and placed in a mixture of toluene and octylamine, the transformation was found to take place and to be assisted by the addition of the CdSe IP sample. A binary IP sample contains corresponding binary PCs and monomers (Mo) and fragments (Fr). We argue that the transformation pathway is enabled by the corresponding ternary PCs, involving the substitution reaction, namely CdTeSe PC-399 + CdSe (Mo/Fr)-1 ⇒ CdTeSe PC-422 + CdSe (Mo/Fr)-2. The present study provides an in-depth understanding of the formation characteristics of the MSCs.

Mounting studies demonstrated both chronic hepatitis B virus (HBV) and chronic hepatitis C virus (HCV) infection might be associated not only with an increased risk of hepatocellular carcinoma but also extrahepatic malignancies, i.e., gastric cancer (GC). However, a quantitative result addressing the association between HBV/HCV infection and GC development is scarce. A systematic search to identify the eligible studies was performed in four databases, including MEDLINE, EMBASE, Cochrane Library, and the PsychINFO. The relationship between HBV/HCV infection and the risk of GC was quantified by calculating the hazard ratio (HR) with a 95% confidence interval (CI). More methodologies of this study were available in the PROSPERO (ID: CRD42021243719). Thirteen included studies involving 7,027,546 individuals (mean age, 42.6-71.9 years) were enrolled in the pooled analyses. Two articles provided the clinical data of both HBV and HCV infections. The proportion of high methodological quality studies was 76.9% (10/13). Synthetic results from 10 eligible studies of HBV showed that HBV infection was associated with a significantly higher risk of GC when compared with the healthy controls without HBV infection (pooled HR, 1.26; 95% CI, 1.08–1.47; P = 0.003; heterogeneity, I2 = 89.3%; P< 0.001). In line with this finding, the combined effect derived from five included studies of HCV also supported a significant positive association between chronic HBV infection and GC development (pooled HR, 1.88; 95% CI, 1.28–2.76; P = 0.001; heterogeneity, I2 = 74.7%; P = 0.003). In conclusion, both chronic HBV and HCV infections were related to a high risk of GC. The plausible mechanisms underlying such association might be correlated to HBV/HCV infection-induced persistent inflammation, immune dysfunction, and cirrhosis.Systematic Review RegistrationPROSPERO (http://www.crd.york.ac.uk/PROSPERO), identifier (CRD42021243719).