Large or transmural defects induced by gastrointestinal endoscopic manipulations are difficult to close, although complete closure is recommended for better recovery. Endoscopic purse-string assisted suturing (EPSS) has been used in clinical practice and has proven to be an effective and safe technique for the closure of large mucosal defects. However, details regarding the efficacy of endoscopic pre-purse-string suture (P-EPSS) are unknown, especially that it offers several advantages over conventional EPSS (C-EPSS).To elucidate the outcomes of EPSS-assisted closure in different clinical situations, and evaluate the efficacy of P-EPSS.This retrospective observational study included a total of 180 patients who underwent closure assisted by P-EPSS (n = 63) or C-EPSS (n = 117) between July 2014 and June 2020. The P-EPSS and C-EPSS groups were compared and the intergroup differences in aspects such as the lesion size, location, and mor-phology, incidence of complete closure, intraoperative perforation, and delayed adverse events were evaluated. Data on the features and clinical course of cases with adverse events were collected for further analysis.Patients with lesion size larger than 3 cm, lesions located at the fundus of stomach, or submucosal tumors originating from the deep mucosa were more likely to undergo P-EPSS-assisted closure. The P-EPSS group showed a sign-ificantly higher proportion of intraoperative perforation (56% vs 17%) and a much shorter procedure time (9.06 ± 6.14 min vs 14.84 ± 7.25 min). Among adverse events, the incidence of delayed perforation (5% vs 4%; P = 0.82) and delayed bleeding (3% vs 4%; P = 0.96) did not differ significantly between the groups. Multivariate analysis revealed that lesions with incomplete closure [odds ratio (OR) = 21.33; 95% confidence interval (CI): 5.45-83.45; P < 0.01] or size greater than 3 cm (OR = 3.14; 95%CI: 1.08-9.18; P = 0.039) showed a statistical tendency to result in an increase in delayed adverse events.The present study revealed that EPSS could achieve secure complete closure of mucosal defect. P-EPSS could shorten the procedure and yield complete closure of mucosal defects. Rather than closure-type selection, incomplete closure or lesion size larger than 3 cm were associated with worse outcomes.
Abstract In the present study, petroleum‐free production of alkylated phenols from glycerol was achieved by judicious use of microbial biosynthesis and heterogeneous catalysis with the aim to advance biomass conversion to industrially relevant chemical products. First, metabolically engineered bacterium Escherichia coli was adopted to convert glycerol to phenol. Biophenol was then extracted from the cell culture using select polymeric resins. Desorption of phenol was achieved with tertiary butyl alcohol, which serves also as a reactant in subsequent heterogeneous catalytic reaction. The adopted resins were also compared as catalysts for alkylation of phenol to tert‐butyl phenolic products. Interestingly, the resins exhibited different phenol adsorption and catalytic reactivities. The holistic approach developed by this study offers a unique opportunity to synthesize end products directly from glycerol that cannot be achieved in such an efficient manner (i.e., low temperature, low pressure, and high selectivity) by using microbial biosynthesis or heterogeneous catalysis approaches alone.
Abstract Nitrogen transport from terrestrial to aquatic environments could cause water quality deterioration and eutrophication. By sampling in the high- and low-flow periods in a highly disturbed coastal basin of southeast China, hydrochemical characteristics, nitrate stable isotope composition, and the Bayesian mixing model were combined to determine the sources and transformation of nitrogen. Nitrate was the main form of nitrogen. Nitrification, nitrate assimilation, and NH4+volatilization were the main nitrogen transformation processes, whereas denitrification was limited due to the high flow rate and unsuitable physicochemical properties. For both sampling periods, non-point source pollution from the upper to the middle reaches was the main source of nitrogen, especially in the high-flow period. In addition to synthetic fertilizer, atmospheric deposition and sewage and manure input were also major nitrate sources in the low-flow period. Hydrological condition was the main factor determining nitrate transformation in this coastal basin, despite the high degree of urbanization and the high volume of sewage discharge in the middle to the lower reaches. The findings of this study highlight that the control of agricultural non-point contamination sources is essential to pollution and eutrophication alleviation, especially for watersheds that receive high amounts of annual precipitation.
Based on the requirements of growth and development of Brazilian upland ratooning rice(IAPAR-9) for the climate conditions and the experimental results of introduced rationing rice in Guangxi,the climate division indexes for planting of brazilian upland ratooning rice were determined.The spatial computative model for the climate division index was established by the methods of mathematics statistics.And the correlative values of climatic elements were worked out on small grid of l km x l km with GIS.By the function of spatial analyses and multi_overlapping method of GIS,Fitting region were partitioned for planting brazilian upland ratooning rice in Guangxi,The scientific basis with reasonable distribution of developing brazilian upland ratooning rice were provided in Guangxi according to the result.
This study analyzed the anthropogenic influences on the hydrochemical composition characteristics of the groundwater in Xiamen City, Fujian province, China, and their evolution. Based on the hydrochemical data of the groundwater of 1993 and 2019–2021, this study identified the indices of the anthropogenic influences using mathematical and statistical analysis methods, such as contrast coefficient, standard deviation, and Mahalanobis distance. The analytical results are summarized as follows: (1) the number of the indices affecting the groundwater quality in Xiamen increased from nine in 1993 to 15 in 2019, and the six increased indicators included NO3−, Pb, NH4+, Al3+, NO2− and Cu (the contribution rates to poor-quality were 26.0%, 16.3%, 10.6%, 4.1%, 0.8% and 0.8%, respectively) which were related to the input of human activities. During this period, the number of hydrochemical types increased from 19 in 1993 to 28 in 2019, with a decrease in the water of the HCO3 type and an increase in the water of Cl and SO4 types; (2) In 2019, NO3− had higher content than SO42− in the groundwater and became a major anion, forming the water of NO3 type; (2) as indicated by the analytical results obtained using the Mahalanobis distance method, areas with strong anthropogenic influences include densely populated areas and areas with intensively distributed industrial enterprises, while anthropogenic influences are very weak in the northern forest land area.
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