BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require furt...BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require further clinical evaluation and investigation.AIM To explore the application value of the"five steps four quadrants"modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients.METHODS A total of 52 patients who underwent LPD via the"five steps four quadrants"modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively.The patients'body mass index(BMI),preoperative laboratory indices,intraoperative variables and postoperative complications were recorded.The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed.RESULTS Among the 52 patients,36 were males and 16 were females,and the average age was 62.2±11.0 years.There were 26 patients with pancreatic head cancer,16 patients with periampullary cancer,and 10 patients with distal bile duct cancer.The BMI was 22.3±3.3 kg/m²,and the median total bilirubin(TBIL)concentration was 57.7(16.0-155.7)µmol/L.All patients successfully underwent the"five steps four quadrants"modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage.Correlation analysis revealed significant associations between preoperative BMI(r=0.3581,P=0.0091),TBIL level(r=0.2988,P=0.0341),prothrombin time(r=0.3018,P=0.0297)and lymph node dissection time.Moreover,dissection time was significantly correlated with intraoperative blood loss(r=0.7744,P<0.0001).Further stratified analysis demonstrated that patients with a preoperative BMI≥21.9 kg/m²and a TIBL concentration≥57.7μmol/L had significantly longer lymph node dissection times(both P<0.05).CONCLUSION The"five steps four quadrants"modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD.This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve;thus,it is worthy of further clinical promotion and application.展开更多
In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements ha...In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements have been applied for establishing, the stoichiometry and whenever possible, the stability constants of the chelates formed. The method of continuous variations was necessary to determine first whether, the metal ion and the ligand ethylene diamine form one or more than one chelate, when more than one chelate formed, the results obtained depend on the wavelength and for meaningful conclusions the wavelengths were carefully selected. The empirical formulae of the chelates were further substantiated by the molar ratio method. The effect of time and temperature on the formation and stability of these chelates in solution is also studied. The stability constants, K1 and K2 for the copper (II) chelates were calculated, though reliable, and are comparable to literature values.展开更多
The chloroaluminate ionic liquid,composed of AlCl3 and 1-butyl-3-methylimidazolium chloride(Cl),is used as the solvent and catalyst to synthesize α-hydroxy esters from alkene and glyoxylate via the glyoxylateene re...The chloroaluminate ionic liquid,composed of AlCl3 and 1-butyl-3-methylimidazolium chloride(Cl),is used as the solvent and catalyst to synthesize α-hydroxy esters from alkene and glyoxylate via the glyoxylateene reaction.Under the reaction conditions of 15 ℃,4 h,and AlCl3/Cl molar ratio of 2,the ethyl α-hydroxy-4-phenyl-4-pentenoate with high yield(95.2%) is obtained in the reaction of α-methyl styrene and ethyl glyoxylate.Other α-hydroxy esters can also be obtained in high yields through the glyoxylate-ene reaction.Moreover,the chloroaluminate ionic liquid can be reused several times.展开更多
In order to extend the eN method to general three-dimensional boundary layers, the conservation law of the imaginary parts for the wave parameters with a fixed wave vector is deduced. The compatibility relationship ...In order to extend the eN method to general three-dimensional boundary layers, the conservation law of the imaginary parts for the wave parameters with a fixed wave vector is deduced. The compatibility relationship (CR) and the general theory of ray tracing (RT), which have been extensively used in conservative systems, are applied to a general three-dimensional boundary layer belonging to non-conservative systems. Two kinds of eN methods, i.e., the eN-CR method and the eN-RT method, are established. Both the two kinds of methods can wavenumber and the amplitude of the be used to predict the evolutions of the spanwise disturbances in general three-dimensional boundary layers. The reliability of the proposed methods is verified and validated by performing a direct numerical simulation (DNS) in a hypersonic general three-dimensional boundary layer over an aircraft model. The results are also compared with those obtained by other eN methods, indicating that the proposed methods have great potential applications in improving the transition prediction accuracy in general three-dimensional boundary layers.展开更多
AIM: To evaluate the efficacy of circumferential endoscopic mucosal resection (EMR) with a tissue-anchoring device in comparison to forceps precut EMR and conventional endoscopic submucosal dissection (ESD). METHODS: ...AIM: To evaluate the efficacy of circumferential endoscopic mucosal resection (EMR) with a tissue-anchoring device in comparison to forceps precut EMR and conventional endoscopic submucosal dissection (ESD). METHODS: The study was designed as a prospective, randomized, ex vivo study. Fresh ex vivo specimens were harvested from adult white Yorkshire pigs weighing 30-50 kg. Seventy-five standardized, artificial lesions measuring 3 cm × 3 cm were created by methy- lene blue tattoo at the greater curvature in fresh ex vivo stomachs using the EASIE-R simulator platform (Endosim LLC, Berlin, MA, United States). The three advanced endoscopists performed the three resection techniques such as circumferential EMR using the tissue-anchoring device (TA-EMR), forceps precut EMR (FP-EMR), and endoscopic submucosal dissection. The endoscopists and the type of cutting methods were determined randomly by grouped randomized selection.The resection bed was grossly inspected to determine whether the lesion was resected "en-bloc " (defined as no remaining mucosal tattoo remaining on specimen). The resection bed was also probed for evidence of perforation. The procedural time of circumferential resection, submucosal dissection, and injection frequency were recorded by an independent observer.RESULTS: All 75 created lesions were successfully resected by three advanced endoscopists using the three techniques. The mean ± SD size of resected specimens (long axis) were 39.5 ± 5.6 mm, 36.5 ± 7.3 mm, and 44.6 ± 5.6 mm for TA-EMR, FP-EMR, and ESD respectively. The overall mean dissection time of both the TA- EMR and FP-EMR was significant shorter than ESD (TA- EMR: 5.1 ± 3.3 min, FP-EMR: 3.5 ± 2.0 min vs ESD: 15.8 ± 9.5 min, P < 0.001, P < 0.001). The overall mean total procedure time of both the tissue-anchoring and forceps circumferential EMR was significantly shorter than ESD (TA-EMR: 17.5 ± 6.0 min, FP-EMR: 16.6 ± 6.6 min vs ESD: 28.6 ± 13.9 min, P < 0.001, P < 0.001). The en-bloc resection rate of ESD was 100% (25/25) and the en-bloc resection rate of the TA-EMR (84.0%, 21/25) was higher than for the FP-EMR (60.0%, 15/25), yet not statistically significant (P = 0.18). The perforation rate of each technique was 8.0% (2/25). CONCLUSION: TA-EMR appears to be quicker than ESD, and there was a trend towards improved en bloc resection rate with the TA-EMR when compared to the FP-EMR.展开更多
Among six major types of tea(white,green,oolong,yellow,black,and dark teas)from Camellia sinensis,oolong tea,a semi-fermented tea,with its own unique aroma and taste,has become a popular consumption as indicated by th...Among six major types of tea(white,green,oolong,yellow,black,and dark teas)from Camellia sinensis,oolong tea,a semi-fermented tea,with its own unique aroma and taste,has become a popular consumption as indicated by the increasing production.Representing the characteristic flavonoids of oolong tea,theasinensins are dimeric flavan-3-ols.Many recent studies have indicated that oolong tea and theasinensins possess several health benefit properties.We consider it significant and necessary to have a comprehensive review in the recent advances of oolong tea.Therefore,the aim of the present review is to provide a new perspective on oolong tea and its characteristic phytochemicals,theasinensins associated with health benefits,molecular action pathway,and chemical mechanism of theasinensin formation from scientific evidences available on the literature.Furthermore,the chemical characterization of the oxidation products and the model oxidation system to the chemical changes of theasinensins are also discussed.展开更多
BACKGROUND Single loop reconstruction(SLR) was routine in our institution for patients undergoing pancreatico-duodenectomy(PD). Roux-en Y reconstruction with an isolated gastric limb(RIGL) recently became the reconstr...BACKGROUND Single loop reconstruction(SLR) was routine in our institution for patients undergoing pancreatico-duodenectomy(PD). Roux-en Y reconstruction with an isolated gastric limb(RIGL) recently became the reconstruction of choice.AIM To evaluate the impact of RIGL on incidence and severity of delayed gastric emptying(DGE).METHODS This is a single institution, retrospective analysis of patients undergoing PD. All patients undergoing PD from July 2010 through December 2016 were included in the study. Outcome of RIGL were compared to SLR. Primary measure of outcome included incidence and severity of DGE. Secondary measures of outcome were overall complications and postoperative mortality.RESULTS One hundred and seventy-nine patients were included in the study. Fifty-two had RIGL, 127 had SLR. Overall complication rate was 40.2%, patients in the RIGL group experienced lower rates of DGE(15.4% vs 59.1%, P = 0.001). Other patient related outcomes were also significantly reduced: day of nasogastric tube removal(3 vs 5, P < 0.001), regain of normal diet(8 vs 9, P < 0.001). On multivariate analysis RIGL was associated independently with reduced rates of DGE(P < 0.001, OR 0.14)CONCLUSION The current study shows that RIGL reduces the rate of DGE after PD. Further prospective randomized controlled trials are required to affirm the current data.展开更多
The development of electrical engineering and electronic, communications, smart power grid, and ultra-high voltage transmission technologies have driven the energy system revolution to the next generation: the energy ...The development of electrical engineering and electronic, communications, smart power grid, and ultra-high voltage transmission technologies have driven the energy system revolution to the next generation: the energy internet. Progressive penetration of intermittent renewable energy sources into the energy system has led to unprecedented challenges to the currently wide use of coal-fired power generation technologies. Here, the applications and prospects of advanced coal-fired power generation technologies are analyzed. These technologies can be summarized into three categories:(1) large-scale and higher parameters coal-fired power generation technologies, including 620/650/700 oC ultra-supercritical thermal power and double reheat ultra-supercritical coal-fired power generation technologies;(2) system innovation and specific, highefficiency thermal cycles, which consist of renewable energy-aided coal-fired power generation technologies, a supercritical CO_2 Brayton cycle for coal-fired power plants, large-scale air-cooling coal-fired power plant technologies, and innovative layouts for waste heat utilization and enhanced energy cascade utilization;(3) coal-fired power generation combined with poly-generation technologies, which are represented by integrated gasification combined cycle(IGCC) and integrated gasification fuel cell(IGFC) technologies. Concerning the existing coal-fired power units, which are responsible for peak shaving, possible strategies for enhancing flexibility and operational stability are discussed. Furthermore, future trends for coal-fired power plants coupled with cyber-physical system(CPS) technologies are introduced. The development of advanced, coal-fired power generation technologies demonstrates the progress of science and is suitable for the sustainable development of human society.展开更多
We investigate the absorption properties of cyclotrimethylene trinitramine(RDX) single crystals from ~15 to150 cm^(-1) using the terahertz time-domain spectroscopy. We observe that all the absorption modes exhibit str...We investigate the absorption properties of cyclotrimethylene trinitramine(RDX) single crystals from ~15 to150 cm^(-1) using the terahertz time-domain spectroscopy. We observe that all the absorption modes exhibit strong anisotropic behavior in terms of the crystal orientations. We demonstrate that the anharmonic phonon model can well describe the temperature-dependent behaviors of these absorption modes. These results indicate that the intermolecular interaction plays a major role in the collective motion of large number of RDX molecules. Our findings provide important information for understanding and controlling the dynamic properties in the explosive materials.展开更多
To analyze the effects of width and thickness of each composition element of mixed steel U-rib-stiffened plates on the welding residual stress distribution, the distribution of the U-rib and the plate residual stress ...To analyze the effects of width and thickness of each composition element of mixed steel U-rib-stiffened plates on the welding residual stress distribution, the distribution of the U-rib and the plate residual stress was calculated using a simplified calculation method. The method involved welding the mixed steel U-rib-stiffened plates for a structure with different sizes and different strength ratios of U-rib to plate. Based on a welding residual stress numerical simulation method validated by the blind hole method test, the distribution law of the mixed steel U-rib stiffened plate was studied. The results showed that the change of plate width has little impact on the welding residual stress and that the ratio of the thicknesses of the plate to U-rib stiffeners, the thickness of the plate, and the thickness of the U-rib has a great influence on the distribution of the welding residual stress. The thickness of plate and steel strength also greatly influenced the distribution width of the residual tensile stress. While analyzing the compression capacity of U-rib-stiffened plates, the simplified distribution of welding residual stress was used.展开更多
Two new pentacyclic triterpene acids, 1a, 3b-dihydroxyl-olean-12-en-28-oic acid and 1a, 2a, 3b-trihydroxyl-olean-12-en-28-oic acid, were isolated from the arial parts of Sabia parviflora.
Abiotic stress poses a great threat to plant growth and can lead to huge losses in yield. Gene enolase2 (EN02) is important in resistance to abiotic stress in various organisms. ENO2 T-DNA insertion mutant (enoZ) ...Abiotic stress poses a great threat to plant growth and can lead to huge losses in yield. Gene enolase2 (EN02) is important in resistance to abiotic stress in various organisms. ENO2 T-DNA insertion mutant (enoZ) plants of Arabidopsis thaliana showed complete susceptibility to sodium chloride treatment when were analyzed either as whole plants or by measuring root growth during NaCl treatment. Quantitative real-time RT-PCR (RT-qPCR) was performed to investigate the expression profile of EN02 in response to NaCl stress in Arabidopsis. The transcript level of EN02 was rapidly elevated in 300 mmol L-1 NaCl treatment. ENO2 also responded to 300 mmol L 1 NaCl treatment at the protein level. To illuminate the mechanism underlying EN02 resistance to salt at the transcriptional level, we studied the wild-type and enoZ Arabidopsis lines that were treated with 300 mmol L 1 NaCl for 18 h using 454 GS FLX, which resulted in an expressed sequence tag (EST) dataset. A total of 961 up-regulated and 746 down-regulated differentially expressed genes (DEGs) were identified in the pairwise comparison w-r-18 h:eno2^-18 h. The DEGs were identified and functionally annotated using the databases of Gene Ontology (GO) and the Kyoto encyclopedia of genes and genomes (KEGG). The identified unigenes were subjected to GO analysis to determine biological, molecular, and cellular functions. The biological process was enriched in a total of 20 GO terms, the cellular component was enriched in 13 GO terms, and the molecular function was enriched in 11 GO terms. Using KEGG mapping, DEGs with pathway annotations contributed to 115 pathways. The top 3 pathways based on a statistical analysis were biosynthesis of the secondary metabolites (KO01110), plant-pathogen interactions (KO04626), and plant hormone signal transduction (KO04075). Based on these results, EN02 contributes to increased resistance to abiotic stress. In particular, EN02 is involved in some of the metabolic stress response pathways in Arabidopsis. Our work also demonstrates that this EST dataset will be a powerful resource for further studies of EN02, such as functional analyses, investigations of biological roles, and molecular breeding. Additionally, 3-phosphoglycerate kinase (PGK), 3-phosphoglycerate kinase 1 (PGK1), triosephosphate isomerase (TPI), and pyruvate kinase (PK) in glycolysis interactions with ENO2 were verified using the yeast two-hybrid experiment, and EN02 may regulate the expression of PGK, PGK1, TPI, and PK. Taken together, the results from this study reflects that EN02 gene has an important role in the response to the high salt stress.展开更多
Three new triterpenes, 3β,21α-dihydroxylupen-18(19)-en (1), 3β,25-dihydroxytirucalla- 7,23(24)-dien (2), and 21α-hydroxy-19α-hydrogentaraxastero1-20(30)-en (3) were obtained from an ethyl acetate extr...Three new triterpenes, 3β,21α-dihydroxylupen-18(19)-en (1), 3β,25-dihydroxytirucalla- 7,23(24)-dien (2), and 21α-hydroxy-19α-hydrogentaraxastero1-20(30)-en (3) were obtained from an ethyl acetate extract of the whole plant of Siyekucai (Ixeris chinensis). The structures of 1-3 were determined by spectroscopic methods (EIMS, IR, 1D and 2D NMR).展开更多
In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores....In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores.The thermodynamic model was constructed and the solubility of malachite Cu2(OH)2CO3 in the ammonia-ammonium chloride-ethylenediamine(En)-water system was calculated using the exponential computation method based on both mass balance and charge balance.It is found that the solubility of copper can be increased and the free ammonia concentration can be decreased by submitting partial ammonia with ethylenediamine.The lower free ammonia concentration in the solution is a guarantee to the lower evaporating rate of ammonia.The conditions of malachite Cu2(OH)2CO3 converting to atacamite Cu(OH)1.5Cl0.5 were also studied.A group of experiments were designed to validate the veracity of the results of the thermodynamic calculation.It is found that the thermodynamic model is reliable and it can guide the leaching process.展开更多
基金Supported by Health Research Program of Anhui,No.AHWJ2022b032。
文摘BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require further clinical evaluation and investigation.AIM To explore the application value of the"five steps four quadrants"modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients.METHODS A total of 52 patients who underwent LPD via the"five steps four quadrants"modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively.The patients'body mass index(BMI),preoperative laboratory indices,intraoperative variables and postoperative complications were recorded.The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed.RESULTS Among the 52 patients,36 were males and 16 were females,and the average age was 62.2±11.0 years.There were 26 patients with pancreatic head cancer,16 patients with periampullary cancer,and 10 patients with distal bile duct cancer.The BMI was 22.3±3.3 kg/m²,and the median total bilirubin(TBIL)concentration was 57.7(16.0-155.7)µmol/L.All patients successfully underwent the"five steps four quadrants"modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage.Correlation analysis revealed significant associations between preoperative BMI(r=0.3581,P=0.0091),TBIL level(r=0.2988,P=0.0341),prothrombin time(r=0.3018,P=0.0297)and lymph node dissection time.Moreover,dissection time was significantly correlated with intraoperative blood loss(r=0.7744,P<0.0001).Further stratified analysis demonstrated that patients with a preoperative BMI≥21.9 kg/m²and a TIBL concentration≥57.7μmol/L had significantly longer lymph node dissection times(both P<0.05).CONCLUSION The"five steps four quadrants"modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD.This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve;thus,it is worthy of further clinical promotion and application.
文摘In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements have been applied for establishing, the stoichiometry and whenever possible, the stability constants of the chelates formed. The method of continuous variations was necessary to determine first whether, the metal ion and the ligand ethylene diamine form one or more than one chelate, when more than one chelate formed, the results obtained depend on the wavelength and for meaningful conclusions the wavelengths were carefully selected. The empirical formulae of the chelates were further substantiated by the molar ratio method. The effect of time and temperature on the formation and stability of these chelates in solution is also studied. The stability constants, K1 and K2 for the copper (II) chelates were calculated, though reliable, and are comparable to literature values.
文摘The chloroaluminate ionic liquid,composed of AlCl3 and 1-butyl-3-methylimidazolium chloride(Cl),is used as the solvent and catalyst to synthesize α-hydroxy esters from alkene and glyoxylate via the glyoxylateene reaction.Under the reaction conditions of 15 ℃,4 h,and AlCl3/Cl molar ratio of 2,the ethyl α-hydroxy-4-phenyl-4-pentenoate with high yield(95.2%) is obtained in the reaction of α-methyl styrene and ethyl glyoxylate.Other α-hydroxy esters can also be obtained in high yields through the glyoxylate-ene reaction.Moreover,the chloroaluminate ionic liquid can be reused several times.
基金supported by the National Natural Science Foundation of China(No.11332007)the Natural Science Foundation of Tianjin(No.15JCYBJC19500)
文摘In order to extend the eN method to general three-dimensional boundary layers, the conservation law of the imaginary parts for the wave parameters with a fixed wave vector is deduced. The compatibility relationship (CR) and the general theory of ray tracing (RT), which have been extensively used in conservative systems, are applied to a general three-dimensional boundary layer belonging to non-conservative systems. Two kinds of eN methods, i.e., the eN-CR method and the eN-RT method, are established. Both the two kinds of methods can wavenumber and the amplitude of the be used to predict the evolutions of the spanwise disturbances in general three-dimensional boundary layers. The reliability of the proposed methods is verified and validated by performing a direct numerical simulation (DNS) in a hypersonic general three-dimensional boundary layer over an aircraft model. The results are also compared with those obtained by other eN methods, indicating that the proposed methods have great potential applications in improving the transition prediction accuracy in general three-dimensional boundary layers.
文摘AIM: To evaluate the efficacy of circumferential endoscopic mucosal resection (EMR) with a tissue-anchoring device in comparison to forceps precut EMR and conventional endoscopic submucosal dissection (ESD). METHODS: The study was designed as a prospective, randomized, ex vivo study. Fresh ex vivo specimens were harvested from adult white Yorkshire pigs weighing 30-50 kg. Seventy-five standardized, artificial lesions measuring 3 cm × 3 cm were created by methy- lene blue tattoo at the greater curvature in fresh ex vivo stomachs using the EASIE-R simulator platform (Endosim LLC, Berlin, MA, United States). The three advanced endoscopists performed the three resection techniques such as circumferential EMR using the tissue-anchoring device (TA-EMR), forceps precut EMR (FP-EMR), and endoscopic submucosal dissection. The endoscopists and the type of cutting methods were determined randomly by grouped randomized selection.The resection bed was grossly inspected to determine whether the lesion was resected "en-bloc " (defined as no remaining mucosal tattoo remaining on specimen). The resection bed was also probed for evidence of perforation. The procedural time of circumferential resection, submucosal dissection, and injection frequency were recorded by an independent observer.RESULTS: All 75 created lesions were successfully resected by three advanced endoscopists using the three techniques. The mean ± SD size of resected specimens (long axis) were 39.5 ± 5.6 mm, 36.5 ± 7.3 mm, and 44.6 ± 5.6 mm for TA-EMR, FP-EMR, and ESD respectively. The overall mean dissection time of both the TA- EMR and FP-EMR was significant shorter than ESD (TA- EMR: 5.1 ± 3.3 min, FP-EMR: 3.5 ± 2.0 min vs ESD: 15.8 ± 9.5 min, P < 0.001, P < 0.001). The overall mean total procedure time of both the tissue-anchoring and forceps circumferential EMR was significantly shorter than ESD (TA-EMR: 17.5 ± 6.0 min, FP-EMR: 16.6 ± 6.6 min vs ESD: 28.6 ± 13.9 min, P < 0.001, P < 0.001). The en-bloc resection rate of ESD was 100% (25/25) and the en-bloc resection rate of the TA-EMR (84.0%, 21/25) was higher than for the FP-EMR (60.0%, 15/25), yet not statistically significant (P = 0.18). The perforation rate of each technique was 8.0% (2/25). CONCLUSION: TA-EMR appears to be quicker than ESD, and there was a trend towards improved en bloc resection rate with the TA-EMR when compared to the FP-EMR.
基金This study was made possible by Naresuan University,Phisanulok,Thailand under the International Research University(IRU)program and Anhui Major Demonstration Project for Leading Talent Team on Tea Chemistry and Health,Anhui Department of Education,Hefei,China.
文摘Among six major types of tea(white,green,oolong,yellow,black,and dark teas)from Camellia sinensis,oolong tea,a semi-fermented tea,with its own unique aroma and taste,has become a popular consumption as indicated by the increasing production.Representing the characteristic flavonoids of oolong tea,theasinensins are dimeric flavan-3-ols.Many recent studies have indicated that oolong tea and theasinensins possess several health benefit properties.We consider it significant and necessary to have a comprehensive review in the recent advances of oolong tea.Therefore,the aim of the present review is to provide a new perspective on oolong tea and its characteristic phytochemicals,theasinensins associated with health benefits,molecular action pathway,and chemical mechanism of theasinensin formation from scientific evidences available on the literature.Furthermore,the chemical characterization of the oxidation products and the model oxidation system to the chemical changes of theasinensins are also discussed.
文摘BACKGROUND Single loop reconstruction(SLR) was routine in our institution for patients undergoing pancreatico-duodenectomy(PD). Roux-en Y reconstruction with an isolated gastric limb(RIGL) recently became the reconstruction of choice.AIM To evaluate the impact of RIGL on incidence and severity of delayed gastric emptying(DGE).METHODS This is a single institution, retrospective analysis of patients undergoing PD. All patients undergoing PD from July 2010 through December 2016 were included in the study. Outcome of RIGL were compared to SLR. Primary measure of outcome included incidence and severity of DGE. Secondary measures of outcome were overall complications and postoperative mortality.RESULTS One hundred and seventy-nine patients were included in the study. Fifty-two had RIGL, 127 had SLR. Overall complication rate was 40.2%, patients in the RIGL group experienced lower rates of DGE(15.4% vs 59.1%, P = 0.001). Other patient related outcomes were also significantly reduced: day of nasogastric tube removal(3 vs 5, P < 0.001), regain of normal diet(8 vs 9, P < 0.001). On multivariate analysis RIGL was associated independently with reduced rates of DGE(P < 0.001, OR 0.14)CONCLUSION The current study shows that RIGL reduces the rate of DGE after PD. Further prospective randomized controlled trials are required to affirm the current data.
基金supported by the National Nature Science Foundation of China(Grant No.51821004)supported by National Soft Science Projects:"Frontier tracking research on science and technology in the field of energy" program
文摘The development of electrical engineering and electronic, communications, smart power grid, and ultra-high voltage transmission technologies have driven the energy system revolution to the next generation: the energy internet. Progressive penetration of intermittent renewable energy sources into the energy system has led to unprecedented challenges to the currently wide use of coal-fired power generation technologies. Here, the applications and prospects of advanced coal-fired power generation technologies are analyzed. These technologies can be summarized into three categories:(1) large-scale and higher parameters coal-fired power generation technologies, including 620/650/700 oC ultra-supercritical thermal power and double reheat ultra-supercritical coal-fired power generation technologies;(2) system innovation and specific, highefficiency thermal cycles, which consist of renewable energy-aided coal-fired power generation technologies, a supercritical CO_2 Brayton cycle for coal-fired power plants, large-scale air-cooling coal-fired power plant technologies, and innovative layouts for waste heat utilization and enhanced energy cascade utilization;(3) coal-fired power generation combined with poly-generation technologies, which are represented by integrated gasification combined cycle(IGCC) and integrated gasification fuel cell(IGFC) technologies. Concerning the existing coal-fired power units, which are responsible for peak shaving, possible strategies for enhancing flexibility and operational stability are discussed. Furthermore, future trends for coal-fired power plants coupled with cyber-physical system(CPS) technologies are introduced. The development of advanced, coal-fired power generation technologies demonstrates the progress of science and is suitable for the sustainable development of human society.
文摘We investigate the absorption properties of cyclotrimethylene trinitramine(RDX) single crystals from ~15 to150 cm^(-1) using the terahertz time-domain spectroscopy. We observe that all the absorption modes exhibit strong anisotropic behavior in terms of the crystal orientations. We demonstrate that the anharmonic phonon model can well describe the temperature-dependent behaviors of these absorption modes. These results indicate that the intermolecular interaction plays a major role in the collective motion of large number of RDX molecules. Our findings provide important information for understanding and controlling the dynamic properties in the explosive materials.
文摘To analyze the effects of width and thickness of each composition element of mixed steel U-rib-stiffened plates on the welding residual stress distribution, the distribution of the U-rib and the plate residual stress was calculated using a simplified calculation method. The method involved welding the mixed steel U-rib-stiffened plates for a structure with different sizes and different strength ratios of U-rib to plate. Based on a welding residual stress numerical simulation method validated by the blind hole method test, the distribution law of the mixed steel U-rib stiffened plate was studied. The results showed that the change of plate width has little impact on the welding residual stress and that the ratio of the thicknesses of the plate to U-rib stiffeners, the thickness of the plate, and the thickness of the U-rib has a great influence on the distribution of the welding residual stress. The thickness of plate and steel strength also greatly influenced the distribution width of the residual tensile stress. While analyzing the compression capacity of U-rib-stiffened plates, the simplified distribution of welding residual stress was used.
文摘Two new pentacyclic triterpene acids, 1a, 3b-dihydroxyl-olean-12-en-28-oic acid and 1a, 2a, 3b-trihydroxyl-olean-12-en-28-oic acid, were isolated from the arial parts of Sabia parviflora.
基金funded by the National Natural Science Foundation of China (31470399 and 31270365)
文摘Abiotic stress poses a great threat to plant growth and can lead to huge losses in yield. Gene enolase2 (EN02) is important in resistance to abiotic stress in various organisms. ENO2 T-DNA insertion mutant (enoZ) plants of Arabidopsis thaliana showed complete susceptibility to sodium chloride treatment when were analyzed either as whole plants or by measuring root growth during NaCl treatment. Quantitative real-time RT-PCR (RT-qPCR) was performed to investigate the expression profile of EN02 in response to NaCl stress in Arabidopsis. The transcript level of EN02 was rapidly elevated in 300 mmol L-1 NaCl treatment. ENO2 also responded to 300 mmol L 1 NaCl treatment at the protein level. To illuminate the mechanism underlying EN02 resistance to salt at the transcriptional level, we studied the wild-type and enoZ Arabidopsis lines that were treated with 300 mmol L 1 NaCl for 18 h using 454 GS FLX, which resulted in an expressed sequence tag (EST) dataset. A total of 961 up-regulated and 746 down-regulated differentially expressed genes (DEGs) were identified in the pairwise comparison w-r-18 h:eno2^-18 h. The DEGs were identified and functionally annotated using the databases of Gene Ontology (GO) and the Kyoto encyclopedia of genes and genomes (KEGG). The identified unigenes were subjected to GO analysis to determine biological, molecular, and cellular functions. The biological process was enriched in a total of 20 GO terms, the cellular component was enriched in 13 GO terms, and the molecular function was enriched in 11 GO terms. Using KEGG mapping, DEGs with pathway annotations contributed to 115 pathways. The top 3 pathways based on a statistical analysis were biosynthesis of the secondary metabolites (KO01110), plant-pathogen interactions (KO04626), and plant hormone signal transduction (KO04075). Based on these results, EN02 contributes to increased resistance to abiotic stress. In particular, EN02 is involved in some of the metabolic stress response pathways in Arabidopsis. Our work also demonstrates that this EST dataset will be a powerful resource for further studies of EN02, such as functional analyses, investigations of biological roles, and molecular breeding. Additionally, 3-phosphoglycerate kinase (PGK), 3-phosphoglycerate kinase 1 (PGK1), triosephosphate isomerase (TPI), and pyruvate kinase (PK) in glycolysis interactions with ENO2 were verified using the yeast two-hybrid experiment, and EN02 may regulate the expression of PGK, PGK1, TPI, and PK. Taken together, the results from this study reflects that EN02 gene has an important role in the response to the high salt stress.
文摘Three new triterpenes, 3β,21α-dihydroxylupen-18(19)-en (1), 3β,25-dihydroxytirucalla- 7,23(24)-dien (2), and 21α-hydroxy-19α-hydrogentaraxastero1-20(30)-en (3) were obtained from an ethyl acetate extract of the whole plant of Siyekucai (Ixeris chinensis). The structures of 1-3 were determined by spectroscopic methods (EIMS, IR, 1D and 2D NMR).
基金Project(2007CB613604)supported by the National Basic Research Program of ChinaProject(50674104)supported by the National Natural Science Foundation of China
文摘In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores.The thermodynamic model was constructed and the solubility of malachite Cu2(OH)2CO3 in the ammonia-ammonium chloride-ethylenediamine(En)-water system was calculated using the exponential computation method based on both mass balance and charge balance.It is found that the solubility of copper can be increased and the free ammonia concentration can be decreased by submitting partial ammonia with ethylenediamine.The lower free ammonia concentration in the solution is a guarantee to the lower evaporating rate of ammonia.The conditions of malachite Cu2(OH)2CO3 converting to atacamite Cu(OH)1.5Cl0.5 were also studied.A group of experiments were designed to validate the veracity of the results of the thermodynamic calculation.It is found that the thermodynamic model is reliable and it can guide the leaching process.