Previous studies show that the tip clearance loss limits the improvement of pumpjet propulsor (PJP) performance,and the tip clearance flow field is the most complicated part of PJP flow.In this work,the non-cavitation...Previous studies show that the tip clearance loss limits the improvement of pumpjet propulsor (PJP) performance,and the tip clearance flow field is the most complicated part of PJP flow.In this work,the non-cavitation and cavitation hydrodynamic performances of PJP with a tip clearance size of 1 mm are obtained by using the detached-eddy simulation (DES).At constant oncoming velocity,cavitation first occurs on the duct and then disappears with the decrease of the advance ratio.The rotor blade cavitation occurs at the low advance ratio and comprises tip clearance cavitation,tip leakage cavitation,and blade sheet cavitation.In the rotor region,the typical vortices include tip separation vortex,tip leakage vortex,trailing edge shedding vortex,and blade root horseshoe vortex.Combined with the pressure distribution,both the Q and λ2 criteria give reliable results of vortex identification.The cavitation causes an expansion of tip leakage vortex in the circumferential direction and decreases the intensities of tip separation vortex in the whole tip clearance area and tip leakage vortex in the cavitation area,and enhances the strength of tip leakage vortex in the downstream non-cavitation area.展开更多
Co-trimoxazole is a combination antibiotic made up of trimethoprim and sulphamethoxazole that is first line treatment for Pneumocystis jirovecii pneumonia (PJP). Hyperkalaemia is a relatively common side effect of the...Co-trimoxazole is a combination antibiotic made up of trimethoprim and sulphamethoxazole that is first line treatment for Pneumocystis jirovecii pneumonia (PJP). Hyperkalaemia is a relatively common side effect of the trimethoprim component of co-trimoxazole but it is not well recognised by clinicians. The mechanism of action causing hyperkalaemia due to trimethoprim is similar to the potassium sparing diuretic effect of amiloride. It has been suggested on this basis that the hyperkalaemia can be reversed by the administration of furosemide and 0.9% saline to promote kaliuresis. We present what we believe to be the first published case of successfully managing trimethoprim induced hyperkalaemia with furosemide and 0.9% saline allowing the continued use of co-trimoxazole to treat severe PJP.展开更多
基金the National Natural Science Foundation of China(Nos.51709229 and 51879220)the Natural Science Basic Research Plan in Shaanxi Province(No.2018JQ5092)the Fundamental Research Funds for the Central Universities of China(No.3102019HHZY030019)。
文摘Previous studies show that the tip clearance loss limits the improvement of pumpjet propulsor (PJP) performance,and the tip clearance flow field is the most complicated part of PJP flow.In this work,the non-cavitation and cavitation hydrodynamic performances of PJP with a tip clearance size of 1 mm are obtained by using the detached-eddy simulation (DES).At constant oncoming velocity,cavitation first occurs on the duct and then disappears with the decrease of the advance ratio.The rotor blade cavitation occurs at the low advance ratio and comprises tip clearance cavitation,tip leakage cavitation,and blade sheet cavitation.In the rotor region,the typical vortices include tip separation vortex,tip leakage vortex,trailing edge shedding vortex,and blade root horseshoe vortex.Combined with the pressure distribution,both the Q and λ2 criteria give reliable results of vortex identification.The cavitation causes an expansion of tip leakage vortex in the circumferential direction and decreases the intensities of tip separation vortex in the whole tip clearance area and tip leakage vortex in the cavitation area,and enhances the strength of tip leakage vortex in the downstream non-cavitation area.
文摘Co-trimoxazole is a combination antibiotic made up of trimethoprim and sulphamethoxazole that is first line treatment for Pneumocystis jirovecii pneumonia (PJP). Hyperkalaemia is a relatively common side effect of the trimethoprim component of co-trimoxazole but it is not well recognised by clinicians. The mechanism of action causing hyperkalaemia due to trimethoprim is similar to the potassium sparing diuretic effect of amiloride. It has been suggested on this basis that the hyperkalaemia can be reversed by the administration of furosemide and 0.9% saline to promote kaliuresis. We present what we believe to be the first published case of successfully managing trimethoprim induced hyperkalaemia with furosemide and 0.9% saline allowing the continued use of co-trimoxazole to treat severe PJP.
