Lymphatic plastic bronchitis and primary chylothorax: A study based on computed tomography lymphangiography

BACKGROUND This study presents an evaluation of the computed tomography lymphangio-graphy(CTL)features of lymphatic plastic bronchitis(PB)and primary chylotho-rax to improve the diagnostic accuracy for these two diseases.AIM To improve the diagnosis of lymphatic PB or primary chylothorax,a retrospective analysis of the clinical features and CTL characteristics of 71 patients diagnosed with lymphatic PB or primary chylothorax was performed.METHODS The clinical and CTL data of 71 patients(20 with lymphatic PB,41 with primary chylothorax,and 10 with lymphatic PB with primary chylothorax)were collected retrospectively.CTL was performed in all patients.The clinical manifestations,CTL findings,and conventional chest CT findings of the three groups of patients were compared.The chi-square test or Fisher's exact test was used to compare the differences among the three groups.A difference was considered to be statistically significant when P<0.05.RESULTS(1)The percentages of abnormal contrast medium deposits on CTL in the three groups were as follows:Thoracic duct outlet in 14(70.0%),33(80.5%)and 8(80.0%)patients;peritracheal region in 18(90.0%),15(36.6%)and 8(80.0%)patients;pleura in 6(30.0%),33(80.5%)and 9(90.0%)patients;pericardium in 6(30.0%),6(14.6%)and 4(40.0%)patients;and hilum in 16(80.0%),11(26.8%)and 7(70.0%)patients;and(2)the abnormalities on conven-tional chest CT in the three groups were as follows:Ground-glass opacity in 19(95.0%),18(43.9%)and 8(80.0%)patients;atelectasis in 4(20.0%),26(63.4%)and 7(70.0%)patients;interlobular septal thickening in 12(60.0%),11(26.8%)and 3(30.0%)patients;bronchovascular bundle thickening in 14(70.0%),6(14.6%)and 4(40.0%)patients;localized mediastinal changes in 14(70.0%),14(34.1%),and 7(70.0%)patients;diffuse mediastinal changes in 6(30.0%),5(12.2%),and 3(30.0%)patients;cystic lesions in the axilla in 2(10.0%),6(14.6%),and 2(20.0%)patients;and cystic lesions in the chest wall in 0(0%),2(4.9%),and 2(4.9%)patients.CONCLUSION CTL is well suited to clarify the characteristics of lymphatic PB and primary chylothorax.This method is an excellent tool for diagnosing these two diseases.

Effect of CaO/Al_(2)O_(3)on structure,viscosity,and surface tension of electroslag remelting-type CeO_(2)-bearing slag

The structure of electroslag remelting-type CaF_(2)–CaO–Al_(2)O_(3)–CeO_(2)slag with various CaO/Al_(2)O_(3)mass ratios and its correlation with viscosity and surface tension were investigated.The Raman analysis of the slag shows that with increasing CaO/Al_(2)O_(3)mass ratio from 0.70 to 1.29 in the slag,the polymerization degree of the slag decreased,which was because more complex[AlO_(4)]-tetrahedral units of Q_(Al)^(3) and Q_(Al)^(4)were depolymerized to form relatively simpler structural units Q_(Al)^(0),Q_(Al)^(1),and Q_(Al)^(2),and the excess oxygen ions introduced by CaO promoted the transformation of[AlO_(4)]-tetrahedral units to[AlO_(6)]-octahedral units.Increasing CaO/Al_(2)O_(3)mass ratio has an obvious effect on reducing the viscosity and activation energy for viscous flow of the slag,resulting from the depolymerization of the slag.Owing to the decrease in the polymerization degree and the increase in the total Ca^(2+)content of the slag,the surface tension of the slag increases with the increase in CaO/Al_(2)O_(3)mass ratio.The surface tension of the slag changes slightly with the temperature,irrespective of CaO/Al_(2)O_(3)mass ratio from 0.70 to 1.29 in the slag.

Evolution of MnS and MgO·Al_(2)O_(3) inclusions in AISI M35 steel during electroslag remelting

Thermodynamics and kinetics of dissociation and precipitation of MnS inclusions,as well as the effect of reoxidation in liquid steel on MgO·Al_(2)O_(3)inclusions in AISI M35 steel during electroslag remelting(ESR)process were investigated.The inclusions found in the consumable electrode were MnS,MgO·Al_(2)O_(3)and MnS adhering to MgO·Al_(2)O_(3).MnS inclusions were nearly spherical and ellipse in morphology,and most of them were less than 2μm in size.MgO·Al_(2)O_(3)inclusions were polygonal and nearly spherical and most about 1-4μm in size.The inclusions in ESR ingot observed by scanning electron microscopy-energy-dispersive X-ray spectrometer were polygonal and nearly spherical MgO·Al_(2)O_(3).MnS inclusions in the consumable electrode were completely dissociated before the liquid film dripping into molten slag pool.The controlling step of MnS inclusions dissociation was the mass transfer of[Mn]in the liquid steel.During the solidification process,the thermodynamic driving force could not meet MnS inclusions precipitation before the solid fraction exceeds 0.996,and the kinetics condition is too poor for the growth of MnS inclusions in the steel when the solid fraction is larger than 0.996.MgO·Al_(2)O_(3)inclusions in ESR ingot originated from the remained MgO·Al_(2)O_(3)inclusions in consumable electrode and the fresh ones formed by the reaction between dissolved magnesium,oxygen and aluminum in liquid steel.