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Abstract Limited endoscopic sphincterotomy (EST) combined with endoscopic papillary balloon dilation (EPBD) is widely used. However, the optimal duration of small balloon dilation in choledocholithiasis remains controversial. We aimed to determine the optimal duration for 10 mm diameter balloon dilation after limited EST in choledocholithiasis. In this randomized controlled clinical trial, 320 patients were randomly assigned to receive small balloon dilation (10 mm in diameter) for 1 min (n = 160) or 3 min (n = 160) after deep bile duct cannulation. No significant difference in success rate of stone extraction between the two groups was observed. The incidence of post-ERCP pancreatitis (PEP) was higher in the 1 min group (10.6%) than in the 3 min group (4.4%) (P = 0.034). The logistic regression analysis showed that guidewire into the pancreatic duct, cannulation time > 5 min and 1 min balloon dilation were independent risk factors for PEP. There were no significant differences in other post-ERCP adverse events such as acute cholangitis, bleeding, perforation, etc. between the two groups. In conclusion, 3 min in duration was determined to be the optimal dilation condition for the removal of common bile duct stones.

Recently, serious concerns have been raised about potential safety risk posed by exogenous pesticide contaminants in herbal medicines. It is highly desirable to have reliable detection and determination of suspected pesticide residues for understanding of their overall quality. However, inherent metabolites abundant in herbal medicines typically make screening of trace-level pesticide residues arduous. Taking Lonicerae Japonicae Flos (LJF) as an example, the current study investigated the capability of a three-dimensional separation system, ultra high-performance liquid chromatography tandem ion mobility/quadrupole time-of-flight mass spectrometry (UPLC-IM/Q-TOF MS), for qualitative detection of numerous pesticides when suffering from complex matrix interferences. The comparison of collision gases was first performed to improve unwanted dissociations of pesticides, particularly labile ones, and nitrogen was ultimately chosen instead of argon. Further optimization of key MS parameters resulted a data-independent high-definition MSE (HDMSE) method was developed. Then, an in-house pesticide scientific library (PSL) containing 438 pesticides was constructed following a four-step workflow. Based on multi-dimensional information in this library, different identification criteria were compared and an enhanced qualitative screening approach for 432 targeted pesticides was finally proposed and validated. By its application to 104 batches of LJFs, the approach was demonstrated effective in resolving complex matrix interferences. Moreover, collision cross section (CCS) for identification purpose was favorable to improve detection sensitivity while maintain ideal accuracy.

BACKGROUND The determination of impurity elements in hydrometallurgical zinc sulfate solution is helpful to optimize the composition of electrolytes, reduce energy consumption, and accurately feed and improve the purity of smelting metal. Impurity elements in the wet zinc smelting process are usually determined by manual sampling. The sample needs to be diluted before the equipment analysis is performed due to high content of zinc and sulfuric acid, which is difficult to achieve automatic analysis. OBJECTIVES In order to determine the online analysis of impurity elements in the solution of zinc smelting process and meet the current requirements of the hydrometallurgical industry. METHODS An automatic industrial on-line filtration/dilution combined with inductively coupled plasma-optical emission spectrometry (ICP-OES) was used. By optimizing key parameters and selecting appropriate analysis lines, a method for the rapid determination of copper, cadmium, cobalt and iron in zinc smelting solution was developed. RESULTS The experimental results showed that the linear relationship of each element was good, the correlation coefficient was greater than 0.9998, the relative standard deviation was 0.72%-1.39% (n=6), and the spiked recovery was 95%-110%. CONCLUSIONS The factory on-line automatic analysis system can replace traditional manual sampling to achieve automatic analysis. The results of on-line analysis are compared with those of manual sampling in actual production, showing good consistency. This method can be used to fully achieve automatic analysis, simple operation, accurate and reliable results, and is suitable for the analysis of impurity elements in zinc smelting.

Based on different high-entropy alloys (HEAs) systems, the latest research progress in additive manufactured high-entropy alloys was reviewed. The rapid solidification microstructure, segregation and precipitation behaviors of high-entropy alloys fabricated by additive manufacturing with different compositions were described. Especially, the analysis was focused on the mechanical properties, deformation and strengthening mechanisms. It was pointed out that the appropriate additive manufacturing process should be selected for different high-entropy alloy systems, and the influencing factors of forming quality need to be further studied. Finally, it was proposed that high-entropy alloys with both excellent strength and high plasticity can be developed and prepared by additive manufacturing technology.

BackgroundEndoscopic retrograde cholangiopancreatography (ERCP) has become an important method to diagnose and treat biliary-pancreatic diseases. Perforations are infrequent but serious complications can occur during ERCPs. However, it is unclear which patients are suitable for surgery and when these patients should receive surgery.AimTo analyze the outcome of 45 patients with endoscopic retrograde cholangiopancreatography (ERCP) related perforation.Materials and methodsWe retrospectively reviewed all 45 patients with ERCP-related perforation between January 2003 and December 2017, and observed the location and causes of perforation, treatment strategies, and mortality.ResultsTwenty thousand four hundred and seventy-nine patients received ERCP procedures from January 2003 to December 2017 in our digestive endoscopy center. Forty-five patients suffered from ERCP-related perforations. The incidence rate of ERCP-related perforations was 0.22%. Twenty-six patients suffered from periampullary perforations, 15 patients suffered from duodenal wall perforations, 1 patient suffered from a fundus perforation, 1 patient suffered from a residual gallbladder duct perforation, 1 patient suffered from a papillary diverticulum perforation, and 1 patient suffered from an intrahepatic bile duct perforation. Six patients with duodenal perforations underwent surgery, and the other patients received conservative treatment. One patient with a duodenal perforation and ERCP-related pancreatitis died of heart failure, and all the other patients recovered. The mortality rate was 2.2%.ConclusionEndoscopic closure is seen as the first method for treating Stapfer type I perforations in the early phase, and surgery is seen as a remedial method when local treatment was failed. The Stapfer type II to type IV perforations can recover by conservative treatment.

Platycodon root, a medicinal food homology species which has been used in Asian countries for hundreds of years, is now widely cultivated in China. Treatment with paclobutrazol, a typical plant growth retardant, has raised uncertainties regarding the quality of Platycodon root, which have been rarely investigated. In the present study, metabolomic and lipidomic differences were revealed by ultra-high performance liquid chromatography coupled to ion mobility-quadrupole time of flight mass spectrometry (UPLC-IM-QTOF-MS). A significant decrease of platycodigenin-type saponins was observed in the paclobutrazol-treated sample. Carrying out a comprehensive quantitative analysis, the contents of total saponins and saccharides were determined to illustrate the mode of action of paclobutrazol on Platycodon root. This study demonstrated an exemplary research model in explaining how the exogenous matter influences the chemical properties of medicinal plants, and therefore might provide insights into the reasonable application of plant growth regulators.

Ionic migration degrades not only the characteristics of halide perovskite solar cells, but also those of perovskite X-ray detectors. Here Yang et al. employ heteroepitaxial BiOBr to passivate Cs2AgBiBr6 double perovskite, which suppresses ionic migration and obtain high performance X-ray detectors.

Recently, due to the development of big data and computer technology, artificial intelligence (AI) has received extensive attention and made great progress. Edge intelligence pushes the computing center of AI from the cloud to individual users, making AI closer to life, but at the same time puts forward higher requirements for the realization of hardware, especially for edge acceleration. Taking convolutional neural networks (CNNs) as an example, which show excellent problem‐solving capabilities in different fields of academia and industry, it still faces issues of enormous computing volume and complex mapping architecture. Based on the computing‐in‐memory property and parallel multiply accumulate (MAC) operations of the emerging nonvolatile memristor arrays, herein the recent research progress of the edge intelligence memristive convolution accelerator is summarized. Furthermore, aiming at improving memristive convolutional accelerators, two potential optimization schemes are also discussed: The compression methods represented by quantization show great potential for static image processing, and the combination of a CNN with a long short‐term memory (LSTM) neural network makes up for the CNN's shortcomings of dynamic target processing. Finally, the future challenges and opportunities of edge intelligence accelerators based on memristor arrays are also discussed.

The exact composition and structure of conductive filaments in hafnia-based memristors are still not fully understood, but recent theoretical investigations reveal that hexagonal HfOx phases close to the h.c.p. Hf structure are probable filament candidates. In this work we list h.c.p. Hf, Hf6O, Hf3O and Hf2O as possible phases for the filament in hafnia memristors. Their differences in lattice parameters, electronic structures and O charge states are studied in details. Migration of O ions for both in-plane and out-of-plane directions in these phases is investigated using first-principles calculations. Both single-phase supercells and filament-in-dielectric models are used for migration barrier calculations, while the latter is proven to be more accurate for the c-direction. The migration of O ions is fastest in metal Hf, while slowest in Hf2O. The existence of O interstitials in Hf tends to hinder the transport of O.

Doping engineering has been recognized as an effective strategy for improving the solar‐to‐hydrogen conversion efficiency of delafossite CuFeO2‐based photocatalysts. However, a comprehensive and systematic study on the doping effect in CuFeO2 is still needed to establish a universal law. To address this, we utilized density functional theory calculations to scrutinize the doping effects of various dopants at different lattice positions. Our findings revealed that Mn replacing Fe and N replacing O are the most readily achievable doping methods under oxygen‐rich and oxygen‐poor conditions, respectively, with a maximum doping concentration of 1020 cm−3 achievable at 900 K. Interestingly, we found that doping with N for O, F for O, and Ni for Cu generates impurity levels capable of capturing photogenerated holes at the top of the valence band, while Zn for Cu and Co for Fe engender impurity levels capable of capturing photogenerated electrons at the bottom of the conduction band, thereby facilitating the separation of photogenerated electron–hole pairs. However, it is worth highlighting that Mn replacing Fe results in impurity levels forming in the middle of the bandgap, acting as a recombination center for photogenerated electron–hole pairs. Furthermore, we discovered that Mg replacing Cu or Fe serves as an example of heterovalent doping capable of promoting the solar‐to‐hydrogen conversion efficiency of CuFeO2. In isovalent doping, dopants with more valence electrons than Cu, dopants with the same valence electron as Fe, and dopants with less valence electron than O can enhance the solar‐to‐hydrogen conversion efficiency of CuFeO2. Overall, this study provides a systematic analysis of the doping effects on CuFeO2‐based photocatalysts and can be applied to doping engineering of ABO2‐type delafossite photocatalytic materials. [ABSTRACT FROM AUTHOR]

Na2Ti3O7/C prepared by a simple acrylamide-assisted sol–gel method shows promising electro-chemical performance as an anode material for sodium-ion batteries. It maintains ca. 100 mAh·g−1 capacity after 100 cycles at 0.1C rate. What's more, it displays about 206.4, 181.2, 151.8, 129.0, 100.3, and 63.4 mAh g−1 at 0.1, 0.2, 0.5, 1, 2, and 5 C current rate, respectively. A capacity of 156.4 mAh·g−1 is recovered when the current density is back to 0.2 C. Density functional theory (DFT) together with molecular dynamics (MD) is used to reveal the Na+ intercalation and diffusion mechanism. Theoretical calculation shows highly active Na+ migration on the b–c planes, with a minimal 0.22 eV energy barrier and the highest diffusion coefficient of 3.8 × 10−7 cm2 s−1 along the b-axis, at the fully charged state. The high vitality of Na+ is maintained until the intercalation level x is more than 0.5. After that, the mobility of Na+ is greatly prohibited, leading to an energy barrier of more than 0.7 eV and a diffusion coefficient within the range 10−14–10−15 cm2 s−1 at the fully discharged state of Na4Ti3O7. The formation energy convex hull determined by means of cluster expansion enables the calculation of voltage profile and the variation of cell parameters, which reveals the low strain (< 1%) feature during the battery cycles. The calculation of electronic structure also reveals an insulator–metal transition upon the sodiation of the Na2Ti3O7 material. [ABSTRACT FROM AUTHOR]