Transpancreatic Sphincterotomy After Double Guidewire Technique Was Noninferior to Primary Transpancreatic Sphincterotomy in Difficult Biliary Cannulation.

BACKGROUND: When unintentional pancreatic duct access occurs during difficult biliary cannulation, the double guidewire (DGW) or transpancreatic sphincterotomy (TPS) may be utilized. DGW can be easily switched to TPS due to the existing guidewire in the pancreatic duct. However, the efficacy of TPS after DGW, named sequential DGW-TPS technique, versus primary TPS has not been assessed. AIMS: Our aim was to compare the benefits and adverse events of sequential DGW-TPS technique and primary TPS. METHODS: We performed a comparative retrospective cohort study that enrolled a total of 117 patients with native papillae. The patients were divided into one of 2 groups according to the primary bile duct access technique (sequential DGW-TPS or primary TPS), both with pancreatic stenting. RESULTS: Between November 2017 and May 2023, a total of 84 patients were grouped into sequential DGW-TPS and 33 into primary TPS. The overall post-ERCP pancreatitis (PEP) rate was 4.3% in the entire cohort, with no statistical differences were observed between the groups in terms of PEP rates (P = 0.927), PEP severity (P = 1.000), first biliary cannulation success (P = 0.621), overall cannulation success (P = 1.000), hyperamylasemia incidence (P = 0.241), elevated amylase levels (P = 0.881), and postoperative hospital stay (P = 0.185). Furthermore, these results remained consistent in multivariable regression analysis. CONCLUSIONS: The sequential DGW-TPS technique showed a comparable safety and biliary cannulation success rate to primary TPS in difficult biliary cannulation. Given the potential long-term complications associated with TPS, DGW should be first if inadvertent pancreatic access occurs, with TPS serving as second only if DGW fails.

Accurate and Rapid Diagnosis of Complex Mitral Valve Aneurysm with Neoplasm via Real-time 3D Transesophageal Echocardiography.

Mitral valve leaflet aneurysm (MVA) is a rare and potentially devastating complication of infective endocarditis. Here, we report the case of a 49-year-old man with mitral endocarditis who had an anterior MVA without aortic morphologic change and only mild regurgitation. By real-time 3D transesophageal echocardiography (TOE), we found two perforations and a hard mass in the aneurysm accompanied with severe regurgitation. The patient underwent valve replacement surgery combined with anti-infection treatment and was successfully discharged. In addition to the case report and literature review related to MVA, we also summarize the application value of RT-3D TOE in these cases.

Molecular Dynamics Simulation and Gas Generation Tracking of Pyrolysis of Bituminous Coal.

To study the generation rules of organic molecules or fragments and the generation paths of some hydrocarbon gases (C2H2/C2H4) and inorganic gases (CO2/H2O/H2/H2S) in the pyrolysis process of bituminous coal at 1000-5000 K, the ReaxFF molecular dynamics module in AMS software was used to simulate the pyrolysis behavior of the Hongqingliang model, Gaojialiang model, and Wiser model. With the increase of temperature, the system potential energy decreases, the endothermic efficiency increases first and then decreases, the fragments of C1-C4 fragments increase, and the gas molecules generated increase. In the pyrolysis process, the oxygen-containing functional groups and hydrogen groups formed H2O and H2 with the increase of temperature. H2S as an intermediate product is always maintained in dynamic equilibrium. CO2 comes from the decarboxylation of the carboxyl groups. When the temperature is lower than 3000 K, C2H4 and C2H2 are mainly formed by the adjacent carbon structure in coal molecules, and C2H4 is formed from the ethyl side chain, the naphthenic structure, and the unstable aromatic rings. C2H2 is formed from naphthene structures and aromatic rings with multiple side chains. When the temperature is higher than 3000 K, C2H4 and C2H2 are mainly formed by the random combination of free radicals generated by the crushing of coal molecules. The research results are of great significance to coal pyrolysis and clean utilization of coal.

Experimental research on the spontaneous combustion of Yangquan coal induced by electrochemical oxidation of pyrite.

The 15# coal seam of Yangmei No.5 Mine, which produces anthracite, which is the least prone to spontaneous combustion, has a serious hidden danger of spontaneous combustion due to the high sulfur content in the coal. Based on the better conductivity of anthracite, we designed an electrolysis experiment to accelerate the electrochemical oxidation of pyrite in coal. Through experiments and analysis of thermodynamic characteristic parameters, it is obtained that the electrochemical oxidation of pyrite and its main products Fe3+ and Fe2+ have a coupled catalytic effect on the spontaneous combustion of high-sulfur coal in Yangquan. Combined with the FTIR test and analysis, it is found that the electrochemical process causes spatial polarization in the coal, so that polar groups such as -OH undergo spatial diversion and increase the activity. Due to the high content of -OH in Yangquan anthracite, the electrochemical process has the greatest effect on promoting -OH oxidation. Fe3+ and Fe2+ act as strong oxidants and free radicals to promote the -CH2- reaction to generate C=O and promote the generation of CO. This research provides a new direction for the exploration of the spontaneous combustion mechanism of high-sulfur anthracite.

Molecular simulation of gases competitive adsorption in lignite and analysis of original CO desorption.

To study the adsorption characteristics of CO, CO2, N2, O2, and their binary-components in lignite coal, reveal the influence of CO2 or N2 injection and air leakage on the desorption of CO in goafs, a lignite model (C206H206N2O44) was established, and the supercell structure was optimized under temperatures of 288.15-318.15 K for molecular simulation. Based on molecular dynamics, the Grand Canonical Monte Carlo method was used to simulate the adsorption characteristics and the Langmuir equation was used to fit the adsorption isotherms of gases. The results show that for single-components, the order of adsorption capacity is CO2 > CO > O2 > N2. For binary-components, the competitive adsorption capacities of CO2 and CO are approximate. In the low-pressure zone, the competitive adsorption capacity of CO2 is stronger than that of CO, and the CO is stronger than N2 or O2. From the simulation, it can be seen that CO2, N2 or O2 will occupy adsorption sites, causing CO desorption. Therefore, to prevent the desorption of the original CO in the goaf, it is not suitable to use CO2 or N2 injection for fire prevention, and the air leakage at the working faces need to be controlled.

Mechanical analysis of the structure of longwall mining hydraulic support.

Existing studies of the structural strength of longwall mining hydraulic support are mainly focused on the force acting on individual supports instead of the general mechanical characteristics of the support group in a fully mechanized coal seam working face. This study combines theoretical analyses and experiments to investigate the mechanical characteristics of a longwall mining hydraulic support group and the stiffness of key support components under different working conditions. The theory of a beam on an elastic foundation was applied to construct a mechanical model for the hydraulic support group. The location and the size of loads on the top beam were determined. Field tests yielded data on the deflection of the roof and loading on the support group along the working face, where the stiffness of end supports varies. The transverse load distribution of the top beam and the offset loading coefficient at different locations along the working-face direction were obtained. A three-dimensional model was constructed for the support group while assembling virtual hydraulic supports using modern virtual modeling theories and methods. Finite element analysis was used to analyze the strength of the hydraulic support. The weakest areas of key components were found to be pinholes connecting the column cylinder to the base and roof of the mine. These results can be applied to achieve secure and stable operations of hydraulic supports in the working face of a thin coal seam, thereby improving the safety and production efficiency of mining operations.

Research on adsorption characteristics of H2S, CH4, N2 in coal based on Monte Carlo method.

In order to study the adsorption characteristics of H2S, CH4 and N2 by coal under different conditions, the new macromolecular structure model of Dongqu No. 2 was constructed, and the grand canonical Monte Carlo (GCMC) method was used to simulate the adsorption process of three types of gases in coal. The dependence of adsorption capacity of coal on its temperature, pressure and moisture content was analyzed. The results show that with the increase of pressure and temperature, adsorption isotherms of all the three gases follow Langmuir model. For pressure greater than 2 MPa, the influence of temperature on adsorption capacity was greater than that of pressure. With rise in temperature, the decrease in rate of H2S adsorption was least and drops in the heat of adsorption of H2S most. This indicates that the adsorption of H2S on coal is more stable than those of CH4 and N2. As the water content of coal increased, its adsorption capacity for the present three gases decreased linearly, and the capacity for H2S (1.77 mmol/g) changed the most. The reduction of free volume linearly and preferential occupation of adsorption sites by water molecules are the main reasons for the highest change in the adsorbed amount of H2S gas.

[Analysis of Causes and Condition of Blood Donation Reaction Under Collective Emergency Blood Donation].

OBJECTIVE: To explore the causes and specific conditions of blood donation reaction under the collective emergency unpaid blood donation, and to provide theoretical basis and decision-making reference for drafting the collective emergency unpaid blood donation and blood donation safety. METHODS: Through a combination of prospective and retrospective models, and statistical methods were used to analyze the causes and conditions of the blood donation response of 10401 people participating in collective emergency unpaid blood donation during 2016.1-2018.8. RESULTS: A total of 10401 person-times donated blood in a sitting manner, and a total of 293 blood donation reactions occurred. By improving the blood donation services year by year, the moderate blood donation reaction during the year 2017 and 2018 was significantly lower than that in 2016 (P＜0.05). In the actual blood donation group of≤100, 200, 300 and 400 ml, the incidence of blood donation reaction was statistically significant (P＜0.05); the incidence of blood donation reaction in the blood donors for 1,2,3 and ＞3 drnations was also statistically significant (P＜0.05); the blood donation reactions rate of B antigen containers was significantly different from the donors without B antigen (P＜0.05); the incidence of blood donation reaction with related to the weight of the donor. CONCLUSION: The blood donation reaction of collective emergency unpaid blood donation closely relates with mental factors, blood donation service, blood donation frequency and body weight of the blood donor. The first blood donation is more likely to produce blood donation reaction. The blood donation volum≤ 100 ml from blood donors is resulted mostly from blood donation reactions.

Protein subcellular localization prediction for Gram-negative bacteria using amino acid subalphabets and a combination of multiple support vector machines.

BACKGROUND: Predicting the subcellular localization of proteins is important for determining the function of proteins. Previous works focused on predicting protein localization in Gram-negative bacteria obtained good results. However, these methods had relatively low accuracies for the localization of extracellular proteins. This paper studies ways to improve the accuracy for predicting extracellular localization in Gram-negative bacteria. RESULTS: We have developed a system for predicting the subcellular localization of proteins for Gram-negative bacteria based on amino acid subalphabets and a combination of multiple support vector machines. The recall of the extracellular site and overall recall of our predictor reach 86.0% and 89.8%, respectively, in 5-fold cross-validation. To the best of our knowledge, these are the most accurate results for predicting subcellular localization in Gram-negative bacteria. CONCLUSION: Clustering 20 amino acids into a few groups by the proposed greedy algorithm provides a new way to extract features from protein sequences to cover more adjacent amino acids and hence reduce the dimensionality of the input vector of protein features. It was observed that a good amino acid grouping leads to an increase in prediction performance. Furthermore, a proper choice of a subset of complementary support vector machines constructed by different features of proteins maximizes the prediction accuracy.

Soap-HT-BLAST: high throughput BLAST based on Web services.

SUMMARY: A high throughput Basic Local Alignment Search Tool (BLAST) system based on Web services is implemented. It provides an alternative BLAST service and allows users to perform multiple BLAST queries at one run in a distributed, parallel environment through the Internet. AVAILABILITY: It is available at http://mammoth.bii.a-star.edu.sg/webservices/htblast/index.html and at http://www.bii.a-star.edu.sg/jiren/download.html

G-PRIMER: greedy algorithm for selecting minimal primer set.

UNLABELLED: G-PRIMER, a web-based primer design program, has been developed to compute a minimal primer set specifically annealed to all the open reading frames in a given microbial genome. This program has been successfully used in the microarray experiment for analyzing the expression of genes in the Xanthomonas campestris genome. AVAILABILITY: It is available at http://mammoth.bii.a-star.edu.sg/gprimer/. Its source code is available upon request.