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There are limited data regarding the safety and efficacy of cold snare polypectomy (CSP) for large colorectal polyps. We evaluated factors affecting the clinical outcomes of CSP for polyps between 5 and 15 mm in size. This was a prospective single-center observational study involving 1000 patients undergoing colonoscopy. Polyps (5–15 mm) were removed using CSP, and biopsies were taken from the resection margin. The primary outcome was the incomplete resection rate (IRR), and was determined by the presence of residual neoplasia on biopsy. Correlations between IRR and polyp size, morphology, histology, and resection time were assessed by generalized estimating equation model. A total of 440 neoplastic polyps were removed from 261 patients. The overall IRR was 2.27%, 1.98% for small (5–9 mm) vs 3.45% for large (10–15 mm) polyps (P =.411). In univariate analysis, the IRR was more likely to be related to sessile serrated lesions (odds ratio [OR], 6.93; 95% confidence interval [CI], 1.88–25.45; P =.004), piecemeal resection (OR, 11.83; 95% CI, 1.20–116.49; P =.034), and prolonged resection time >60 seconds (OR, 7.56; 95% CI, 1.75–32.69; P =.007). In multivariable regression analysis, sessile serrated lesions (OR, 6.45; 95% CI, 1.48–28.03; P =.013) and resection time (OR, 7.39; 95% CI, 1.48–36.96; P =.015, respectively) were independent risk factors for IRR. Immediate bleeding was more frequent with resection of large polyps (6.90% vs 1.42%; P =.003). No recurrence was seen on follow-up colonoscopy in 37 cases with large polyps. CSP is safe and effective for removal of colorectal polyps up to 15 mm in size, with a low IRR. (ClinicalTrials.gov ; Number: NCT03647176). [Display omitted] [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) graphene aerogel and its composite with interconnected pores have aroused continuous interests in energy storage field owning to its large surface area and hierarchical pore structure. Herein, we reported the preparation of 3D nitrogen-doped graphene/polyaniline (N-GE/PANI) composite foam for supercapacitive material with greatly improved electrochemical performance. The 3D porous structure can allow the penetration and diffusion of electrolyte, the incorporation of nitrogen doping can enhance the wettability of the active material and the number of active sites with electrolyte, and both the N-GE and PANI can ensure the high electrical conductivity of total electrode. Moreover, the synergistic effect between N-GE and PANI materials also play an important role on the electrochemical performance of electrode. Therefore, the as-prepared composite foam could deliver a high specific capacitance of 528 F g −1 at 0.1 A g −1 and a high cyclic stability with 95.9% capacitance retention after 5000 charge-discharge cycles. This study provides a new idea on improving the energy storage capacity of supercapacitors by using 3D graphene-based psedocapacitive electrode materials. [ABSTRACT FROM AUTHOR]

In this work, an excellent ternary visible-light all solid Z-scheme photocatalytic heterojunction of g-C 3 N 4 /GO/AgBr has been prepared by the attachment of graphene oxide (GO) to the surface of g-C 3 N 4 , followed by in-situ growth of AgBr nanoparticles on GO sheets. The g-C 3 N 4 /GO/AgBr heterojunction exhibits excellent photocatalytic efficiency for RhB degradation, which is about 17.5, 7.9, 3.5, 4.0 and 2.2 times as high as that of P25, g-C 3 N 4 , AgBr, g-C 3 N 4 /GO and g-C 3 N 4 /AgBr heterojunction, indicating the introduction of GO into the system largely improved the capability of the photocatalysis since GO acted as the charge transmission bridge between g-C 3 N 4 and AgBr. Moreover, the photocatalytic performance of g-C 3 N 4 /GO/AgBr just showed a slight decrease after 4 degradation cycles, demonstrating a high stability of the g-C 3 N 4 /GO/AgBr photocatalyst. The photocatalytic mechanism investigation indicated that O 2 − and h + are the major active species in the photocatalytic process. It is expected that the GO-inserted Z-scheme photocatalytic heterojunction could be applied to practical pollutant degradation. [ABSTRACT FROM AUTHOR]

SnPb-SnAgCu mixed solder joints with Sn-Pb soldering Sn-Ag-Cu Pb-free components are inevitably occurred in the high reliability applications. In this study, the interfacial behaviors in Sn-37Pb and Sn-3.0Ag-0.5Cu mixed solder joints was addressed and compared with Sn-37Pb solder joints and Sn-3.0Ag-0.5Cu solder joints with the influence from isothermal aging and electromigration. Considering the difference on the melting point between Sn-3.0Ag-0.5Cu and Sn-37Pb solder, two mixed solder joints: partial mixing and full mixing between Sn-Pb and Sn-Ag-Cu solders were reached with the peak reflowing temperature of 190 and 250 °C, respectively. During isothermal aging, the intermetallic compound (IMC) layer increased with aging time and its growth was diffusion controlled. There was also no obvious affect from the solder composition on IMC growth. After electromigration with the current density of 2.0 × 10 3 A/cm 2 , Sn-37Pb solder joints showed the shortest lifetime with the cracks observed at the cathode for the stressing time < 250 h. In Sn-3.0Ag-0.5Cu Pb-free solder joints, current stressing promoted the growth of IMC layer at the interfaces, but the growing rate of IMC at the anode interface was far faster than that at the cathode interface. Therefore, there existed an obvious polarity effect on IMC growth in Sn-Ag-Cu Pb-free solder joints. After Sn-37Pb was mixed with Sn-3.0Ag-0.5Cu Pb-free solder, whether the partial mixing or the full mixing between Sn-Pb and Sn-Ag-Cu can obviously depress both the crack formation at the cathode side and the IMC growth at the anode. [ABSTRACT FROM AUTHOR]