Cross sections of electron-loss in H(1s)+ H(1s) collisions and total collisional destruction of H(2s) in H(1s) 4- H(2s) collisions are calculatted by four-body classical-trajectory Monte Caylo (CTMC) meth...Cross sections of electron-loss in H(1s)+ H(1s) collisions and total collisional destruction of H(2s) in H(1s) 4- H(2s) collisions are calculatted by four-body classical-trajectory Monte Caylo (CTMC) method and compared with previous theoretical and experimental data over the energy range of 4-100 keV. For the former a good agreement is obtained within different four-body CTMC calculations, and for the incident energy Ep 〉 10 keV, comparison with the experimental data shows a better agreement than the results calculated by the impact parameter approx- imation. For the latter, our theory predicts the correct experimental behaviour, and the discrepancies between our results and experimental ones are less than 30%. Based on the successive comparison with experiments, the cross sections for excitation to H(2p), single- and double-ionization and H- formation in H(2s)+H(2s) collisions are calculated in the energy range of 4-100 keV for the first time, and compared with those in H(1s)+H(1s) and H(1s)+U(2s) collisions.展开更多
AIM To characterize radiological and clinical factors associated with subsequent surgical intervention in Crohn's disease(CD) patients with intra-abdominal fistulae.METHODS From a cohort of 1244 CD patients seen o...AIM To characterize radiological and clinical factors associated with subsequent surgical intervention in Crohn's disease(CD) patients with intra-abdominal fistulae.METHODS From a cohort of 1244 CD patients seen over an eight year period(2006 to 2014), 126 patients were identified as having intra-abdominal fistulae, and included in the study. Baseline patient information was collected from the medical records. Imaging studies were assessed for: anatomic type and number of fistulae; diameter of the inflammatory conglomerate; length of diseased bowel; presence of a stricture with pre-stenotic dilatation; presence of an abscess; lymphadenopathy; and the degree of bowel enhancement. Multivariate analysis for the prediction of abdominal surgery was calculated via Generalized Linear Models.RESULTS In total, there were 193 fistulae in 132 patients, the majority(52%) being entero-enteric. Fifty-nine(47%) patients underwent surgery within one year of the imaging study, of which 36(29%) underwent surgery within one month. Radiologic features that were associated with subsequent surgery included: multiple fistulae(P = 0.009), presence of stricture(P = 0.02), and an entero-vesical fistula(P = 0.01). Evidence of an abscess, lymphadenopathy, or intense bowel enhancement as well as C-reactive protein levels was not associated with an increased rate of surgery. Patients who were treated after the imaging study with combination immunomodulatory and anti-TNF therapy had significantly lower rates of surgery(P = 0.01). In the multivariate analysis, presence of a stricture [RR 4.5(1.23-16.3), P = 0.02] was the only factor that increased surgery rate.CONCLUSION A bowel stricture is the only factor predicting an increased rate of surgery. Radiological parameters may guide in selecting treatment options in patients with fistulizing CD.展开更多
The partial charge simulation method is presented to solve the characteristicimpedance of the transmission line of specific cross section with an offset inner conductor.Thismethod has a higher accuracy due to the accu...The partial charge simulation method is presented to solve the characteristicimpedance of the transmission line of specific cross section with an offset inner conductor.Thismethod has a higher accuracy due to the accurate satisfaction of the boundary condition on theouter conductor.The combined method of the Gauss elimination and optimization is used tosolve the equation of charge simulation,and it is an effective method for increasing the accuracyand assuring the convergence.The Green’s functions of five transmission lines(i.e,with circular,elliptic,rectangular,trough and slab conductor)are given.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 10434100, 10574018 and 10574020.
文摘Cross sections of electron-loss in H(1s)+ H(1s) collisions and total collisional destruction of H(2s) in H(1s) 4- H(2s) collisions are calculatted by four-body classical-trajectory Monte Caylo (CTMC) method and compared with previous theoretical and experimental data over the energy range of 4-100 keV. For the former a good agreement is obtained within different four-body CTMC calculations, and for the incident energy Ep 〉 10 keV, comparison with the experimental data shows a better agreement than the results calculated by the impact parameter approx- imation. For the latter, our theory predicts the correct experimental behaviour, and the discrepancies between our results and experimental ones are less than 30%. Based on the successive comparison with experiments, the cross sections for excitation to H(2p), single- and double-ionization and H- formation in H(2s)+H(2s) collisions are calculated in the energy range of 4-100 keV for the first time, and compared with those in H(1s)+H(1s) and H(1s)+U(2s) collisions.
文摘AIM To characterize radiological and clinical factors associated with subsequent surgical intervention in Crohn's disease(CD) patients with intra-abdominal fistulae.METHODS From a cohort of 1244 CD patients seen over an eight year period(2006 to 2014), 126 patients were identified as having intra-abdominal fistulae, and included in the study. Baseline patient information was collected from the medical records. Imaging studies were assessed for: anatomic type and number of fistulae; diameter of the inflammatory conglomerate; length of diseased bowel; presence of a stricture with pre-stenotic dilatation; presence of an abscess; lymphadenopathy; and the degree of bowel enhancement. Multivariate analysis for the prediction of abdominal surgery was calculated via Generalized Linear Models.RESULTS In total, there were 193 fistulae in 132 patients, the majority(52%) being entero-enteric. Fifty-nine(47%) patients underwent surgery within one year of the imaging study, of which 36(29%) underwent surgery within one month. Radiologic features that were associated with subsequent surgery included: multiple fistulae(P = 0.009), presence of stricture(P = 0.02), and an entero-vesical fistula(P = 0.01). Evidence of an abscess, lymphadenopathy, or intense bowel enhancement as well as C-reactive protein levels was not associated with an increased rate of surgery. Patients who were treated after the imaging study with combination immunomodulatory and anti-TNF therapy had significantly lower rates of surgery(P = 0.01). In the multivariate analysis, presence of a stricture [RR 4.5(1.23-16.3), P = 0.02] was the only factor that increased surgery rate.CONCLUSION A bowel stricture is the only factor predicting an increased rate of surgery. Radiological parameters may guide in selecting treatment options in patients with fistulizing CD.
文摘The partial charge simulation method is presented to solve the characteristicimpedance of the transmission line of specific cross section with an offset inner conductor.Thismethod has a higher accuracy due to the accurate satisfaction of the boundary condition on theouter conductor.The combined method of the Gauss elimination and optimization is used tosolve the equation of charge simulation,and it is an effective method for increasing the accuracyand assuring the convergence.The Green’s functions of five transmission lines(i.e,with circular,elliptic,rectangular,trough and slab conductor)are given.