Spectroscopic Observation and Modeling of Photonic Modes in CeO2 Nanocubes

Photonic modes in dielectric nanostructures, e.g., wide gap semiconductor like CeO2 (ceria), has potential for various applications such as light harvesting and information transmission. To fully understand the properties of such phenomenon in nanoscale, we applied electron energy-loss spectroscopy (EELS) in scanning transmission electron microscope (STEM) to detect such modes in a well-defined ceria nanocube. Through spectra and mapping, we demonstrated a geometrical difference of mode excitation. By comparing various spectra taken at different location relative to the cube, we also showed the transmission properties of the mode. To confirm our observation, we performed EELS simulation with finite-element dielectric calculations in COMSOL Multiphysics. We also revealed the origin of the modes through the calculation. We purposed a simple analytical model to estimate the energy of photonic modes as well. In all, this work gave a fine description of the photonic modes' properties in nanostructures, while demonstrating the advantage of EELS in characterizing optical phenomena in nanoscale

Table_1_Efficacy and Safety of Radiofrequency Ablation vs. Endoscopic Surveillance for Barrett’s Esophagus With Low-Grade Dysplasia: Meta-Analysis of Randomized Controlled Trials.docx

Background and AimsBarrett’s esophagus with low-grade dysplasia (BE-LGD) carries a risk of progression to Barrett’s esophagus with high-grade dysplasia (BE-HGD) and esophageal adenocarcinoma (EAC). Radiofrequency ablation (RFA) appears to be a safe and efficacious method to eradicate Barrett’s esophagus. However, a confirmed consensus regarding treatment of BE-LGD with RFA vs. endoscopic surveillance is lacking. Therefore, this study aimed to elucidate the efficacy and safety for RFA vs. endoscopic surveillance in decreasing the risk of BE-LGD progression to BE-HGD or EAC.MethodsRelevant studies published before May 1, 2021 were identified by searching relevant medical databases. The primary outcome was the rate of progression BE-LGD to HGD and/or EAC after treatment with RFA and endoscopic surveillance. The secondary outcome was the rate of complete eradication of dysplasia (CE-D) and complete eradication of intestinal metaplasia (CE-IM) after treatment with RFA and endoscopic surveillance. Adverse events were also extracted and evaluated.ResultsThree randomized controlled trials were eligible for analysis. The pooled estimate of rate of neoplastic progression of BE-LGD to HGD or EAC was much lower in the RFA group than the endoscopic surveillance group (RR, 0.25; 95% CI, 0.07–0.93; P = 0.04), with moderate heterogeneity (I2 = 55%). Subgroup analysis based on progression grade was performed. The pooled rate of progression of BE-LGD to HGD was much lower in the RFA group than the endoscopic surveillance group (RR, 0.25; 95% CI, 0.07–0.71; P = 0.01), with low heterogeneity (I2 = 15%). Although the pooled risk of progression of BE-LGD to EAC was slightly lower in the RFA group than the endoscopic surveillance group (RR, 0.56; 95% CI, 0.05–6.76), the result was not statistically significant (P = 0.65). RFA also was associated a higher rate of CE-D and CE-IM both at the end of endoscopic treatment and during follow-up. However, the rate of adverse events was slightly higher after RFA treatment.ConclusionRFA decreases the risk of BE-LGD progression to BE-HGD. However, given the uncertain course of LGD and the potential for esophageal stricture after RFA, treatment options should be fully considered and weighed.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021266128, identifier PROSPERO (CRD42021266128).</p

Table_4_Efficacy and Safety of Radiofrequency Ablation vs. Endoscopic Surveillance for Barrett’s Esophagus With Low-Grade Dysplasia: Meta-Analysis of Randomized Controlled Trials.docx

Background and AimsBarrett’s esophagus with low-grade dysplasia (BE-LGD) carries a risk of progression to Barrett’s esophagus with high-grade dysplasia (BE-HGD) and esophageal adenocarcinoma (EAC). Radiofrequency ablation (RFA) appears to be a safe and efficacious method to eradicate Barrett’s esophagus. However, a confirmed consensus regarding treatment of BE-LGD with RFA vs. endoscopic surveillance is lacking. Therefore, this study aimed to elucidate the efficacy and safety for RFA vs. endoscopic surveillance in decreasing the risk of BE-LGD progression to BE-HGD or EAC.MethodsRelevant studies published before May 1, 2021 were identified by searching relevant medical databases. The primary outcome was the rate of progression BE-LGD to HGD and/or EAC after treatment with RFA and endoscopic surveillance. The secondary outcome was the rate of complete eradication of dysplasia (CE-D) and complete eradication of intestinal metaplasia (CE-IM) after treatment with RFA and endoscopic surveillance. Adverse events were also extracted and evaluated.ResultsThree randomized controlled trials were eligible for analysis. The pooled estimate of rate of neoplastic progression of BE-LGD to HGD or EAC was much lower in the RFA group than the endoscopic surveillance group (RR, 0.25; 95% CI, 0.07–0.93; P = 0.04), with moderate heterogeneity (I2 = 55%). Subgroup analysis based on progression grade was performed. The pooled rate of progression of BE-LGD to HGD was much lower in the RFA group than the endoscopic surveillance group (RR, 0.25; 95% CI, 0.07–0.71; P = 0.01), with low heterogeneity (I2 = 15%). Although the pooled risk of progression of BE-LGD to EAC was slightly lower in the RFA group than the endoscopic surveillance group (RR, 0.56; 95% CI, 0.05–6.76), the result was not statistically significant (P = 0.65). RFA also was associated a higher rate of CE-D and CE-IM both at the end of endoscopic treatment and during follow-up. However, the rate of adverse events was slightly higher after RFA treatment.ConclusionRFA decreases the risk of BE-LGD progression to BE-HGD. However, given the uncertain course of LGD and the potential for esophageal stricture after RFA, treatment options should be fully considered and weighed.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021266128, identifier PROSPERO (CRD42021266128).</p

Table_2_Efficacy and Safety of Radiofrequency Ablation vs. Endoscopic Surveillance for Barrett’s Esophagus With Low-Grade Dysplasia: Meta-Analysis of Randomized Controlled Trials.docx

Background and AimsBarrett’s esophagus with low-grade dysplasia (BE-LGD) carries a risk of progression to Barrett’s esophagus with high-grade dysplasia (BE-HGD) and esophageal adenocarcinoma (EAC). Radiofrequency ablation (RFA) appears to be a safe and efficacious method to eradicate Barrett’s esophagus. However, a confirmed consensus regarding treatment of BE-LGD with RFA vs. endoscopic surveillance is lacking. Therefore, this study aimed to elucidate the efficacy and safety for RFA vs. endoscopic surveillance in decreasing the risk of BE-LGD progression to BE-HGD or EAC.MethodsRelevant studies published before May 1, 2021 were identified by searching relevant medical databases. The primary outcome was the rate of progression BE-LGD to HGD and/or EAC after treatment with RFA and endoscopic surveillance. The secondary outcome was the rate of complete eradication of dysplasia (CE-D) and complete eradication of intestinal metaplasia (CE-IM) after treatment with RFA and endoscopic surveillance. Adverse events were also extracted and evaluated.ResultsThree randomized controlled trials were eligible for analysis. The pooled estimate of rate of neoplastic progression of BE-LGD to HGD or EAC was much lower in the RFA group than the endoscopic surveillance group (RR, 0.25; 95% CI, 0.07–0.93; P = 0.04), with moderate heterogeneity (I2 = 55%). Subgroup analysis based on progression grade was performed. The pooled rate of progression of BE-LGD to HGD was much lower in the RFA group than the endoscopic surveillance group (RR, 0.25; 95% CI, 0.07–0.71; P = 0.01), with low heterogeneity (I2 = 15%). Although the pooled risk of progression of BE-LGD to EAC was slightly lower in the RFA group than the endoscopic surveillance group (RR, 0.56; 95% CI, 0.05–6.76), the result was not statistically significant (P = 0.65). RFA also was associated a higher rate of CE-D and CE-IM both at the end of endoscopic treatment and during follow-up. However, the rate of adverse events was slightly higher after RFA treatment.ConclusionRFA decreases the risk of BE-LGD progression to BE-HGD. However, given the uncertain course of LGD and the potential for esophageal stricture after RFA, treatment options should be fully considered and weighed.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021266128, identifier PROSPERO (CRD42021266128).</p

Table_3_Efficacy and Safety of Radiofrequency Ablation vs. Endoscopic Surveillance for Barrett’s Esophagus With Low-Grade Dysplasia: Meta-Analysis of Randomized Controlled Trials.docx

Background and AimsBarrett’s esophagus with low-grade dysplasia (BE-LGD) carries a risk of progression to Barrett’s esophagus with high-grade dysplasia (BE-HGD) and esophageal adenocarcinoma (EAC). Radiofrequency ablation (RFA) appears to be a safe and efficacious method to eradicate Barrett’s esophagus. However, a confirmed consensus regarding treatment of BE-LGD with RFA vs. endoscopic surveillance is lacking. Therefore, this study aimed to elucidate the efficacy and safety for RFA vs. endoscopic surveillance in decreasing the risk of BE-LGD progression to BE-HGD or EAC.MethodsRelevant studies published before May 1, 2021 were identified by searching relevant medical databases. The primary outcome was the rate of progression BE-LGD to HGD and/or EAC after treatment with RFA and endoscopic surveillance. The secondary outcome was the rate of complete eradication of dysplasia (CE-D) and complete eradication of intestinal metaplasia (CE-IM) after treatment with RFA and endoscopic surveillance. Adverse events were also extracted and evaluated.ResultsThree randomized controlled trials were eligible for analysis. The pooled estimate of rate of neoplastic progression of BE-LGD to HGD or EAC was much lower in the RFA group than the endoscopic surveillance group (RR, 0.25; 95% CI, 0.07–0.93; P = 0.04), with moderate heterogeneity (I2 = 55%). Subgroup analysis based on progression grade was performed. The pooled rate of progression of BE-LGD to HGD was much lower in the RFA group than the endoscopic surveillance group (RR, 0.25; 95% CI, 0.07–0.71; P = 0.01), with low heterogeneity (I2 = 15%). Although the pooled risk of progression of BE-LGD to EAC was slightly lower in the RFA group than the endoscopic surveillance group (RR, 0.56; 95% CI, 0.05–6.76), the result was not statistically significant (P = 0.65). RFA also was associated a higher rate of CE-D and CE-IM both at the end of endoscopic treatment and during follow-up. However, the rate of adverse events was slightly higher after RFA treatment.ConclusionRFA decreases the risk of BE-LGD progression to BE-HGD. However, given the uncertain course of LGD and the potential for esophageal stricture after RFA, treatment options should be fully considered and weighed.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021266128, identifier PROSPERO (CRD42021266128).</p

Exotic Reaction Front Migration and Stage Structure in Lithiated Silicon Nanowires

Nanostructured silicon anodes, which possess extremely high energy density and accommodate large strain without pulverization, have been developed rapidly for high-power lithium ion batteries. Here, using in situ transmission electron microscopy, the lithiation behavior of silicon nanowires with diameters smaller than 60 nm was investigated. The study demonstrated a direct dependence of the self-limiting lithiation on the pristine diameter. A “punch-through” lithiation process at the core of nanowires with pristine diameters slightly larger than the self-limiting threshold is suggested to occur with the consequent formation of a stage structure. Our work demonstrates the crucial role of mechanical stress and local defects in determining the migration and geometry of the reaction front at the mesoscopic scale. This intriguing finding holds critical significance for the application of silicon nanostructures in high-power lithium ion batteries

Ayreshire cow judging at Interior Provincial Exhibition

Nanostructured silicon anodes, which possess extremely high energy density and accommodate large strain without pulverization, have been developed rapidly for high-power lithium ion batteries. Here, using <i>in situ</i> transmission electron microscopy, the lithiation behavior of silicon nanowires with diameters smaller than 60 nm was investigated. The study demonstrated a direct dependence of the self-limiting lithiation on the pristine diameter. A “punch-through” lithiation process at the core of nanowires with pristine diameters slightly larger than the self-limiting threshold is suggested to occur with the consequent formation of a stage structure. Our work demonstrates the crucial role of mechanical stress and local defects in determining the migration and geometry of the reaction front at the mesoscopic scale. This intriguing finding holds critical significance for the application of silicon nanostructures in high-power lithium ion batteries

Exotic Reaction Front Migration and Stage Structure in Lithiated Silicon Nanowires

Nanostructured silicon anodes, which possess extremely high energy density and accommodate large strain without pulverization, have been developed rapidly for high-power lithium ion batteries. Here, using <i>in situ</i> transmission electron microscopy, the lithiation behavior of silicon nanowires with diameters smaller than 60 nm was investigated. The study demonstrated a direct dependence of the self-limiting lithiation on the pristine diameter. A “punch-through” lithiation process at the core of nanowires with pristine diameters slightly larger than the self-limiting threshold is suggested to occur with the consequent formation of a stage structure. Our work demonstrates the crucial role of mechanical stress and local defects in determining the migration and geometry of the reaction front at the mesoscopic scale. This intriguing finding holds critical significance for the application of silicon nanostructures in high-power lithium ion batteries

Exsolution–Dissolution of Supported Metals on High-Entropy Co₃MnNiCuZnO<i>_x</i>: Toward Sintering-Resistant Catalysis

Herein, in situ generation of CuCoNi nanoalloys over a high-entropy oxide Co3MnNiCuZnOx matrix has been employed to generate a sintering-resistant metal-oxide interface for the CO2 hydrogenation reaction. The high-entropy Co3MnNiCuZnOx catalyst with a single reverse spinel structure was synthesized by a mechanochemical redox-based process and thermal treatment just at 600 °C. Interestingly, the entropy-driven force allows the exsolution and dissolution of CuCoNi alloys under reductive and oxidative recyles, which results in the dynamics confinement of the supported metals. With high temperature (500 °C) CO2 hydrogenation as a model reaction, the restriction of CuCoNi nanoparticles over a high-entropy Co3MnNiCuZnOx matrix guaranteed long-term thermal stability (>100 h). In comparison, binary CoMnOx as a control catalyst deactivated in 10 h. This high-entropy stabilization may inspire a number of sintering-resistant catalysts in the near future