A vortex is intuitively recognized as the rotational/swirling motion of fluids,but a rigorous and universally-accepted definition is still not available.Vorticity tube/filament has been regarded equivalent to a vortex...A vortex is intuitively recognized as the rotational/swirling motion of fluids,but a rigorous and universally-accepted definition is still not available.Vorticity tube/filament has been regarded equivalent to a vortex since Helmholtz proposed the concepts of vorticity tube/filament in 1858 and the vorticity-based methods can be categorized as the first generation of vortex identification methods.During the last three decades,a lot of vortex identification methods,including 0,A,and Aci criteria,have been proposed to overcome the problems associated with the vorticity-based methods.Most of these criteria are based on the Cauchy-Stokes decomposition and/or eigenvalues of the velocity gradient tensor and can be considered as the second generation of vortex identification methods.Starting from 2014,the Vortex and Turbulence Research Team at the University of Texas at Arlington(the UTA team)focus on the development of a new generation of vortex identification methods.The first fruit of this effort,a new Omega(/2)vortex identification method,which defined a vortex as a connected region where the vorticity overtakes the deformation,was published in 2016.In 2017 and 2018,a Liutex(previously called Rortex)vector was proposed to provide a mathematical definition of the local rigid rotation part of the fluid motion,including both the local rotational axis and the rotational strength.Liutex/Rortex is a new physical quantity with scalar,vector and tensor forms exactly representing the local rigid rotation of fluids.Meanwhile,a decomposition of the vorticity to a rotational part namely Liutex/Rortex and an anti-symmetric shear part(RS decomposition)was introduced in 2018,and a universal decomposition of the velocity gradient tensor to a rotation part(7?)and a non-rotation part(NR、was also given in 2018 as a counterpart of the traditional Cauchy-Stokes decomposition.Later in early 2019,a Liutex/Rortex based Omega method called Omega-Liutex,which combines the respective advantages of both Liutex/Rortex and Omega methods,was dev展开更多
Reversible pump turbines are widely employed in the pumped hydro energy storage power plants. The frequent shifts among various operational modes for the reversible pump turbines pose various instability problems, e.g...Reversible pump turbines are widely employed in the pumped hydro energy storage power plants. The frequent shifts among various operational modes for the reversible pump turbines pose various instability problems, e.g., the strong pressure fluctuation, the shaft swing, and the impeller damage. The instability is related to the vortices generated in the channels of the reversible pump turbines in the generating mode. In the present paper, a new omega vortex identification method is applied to the vortex analysis of the reversible pump turbines. The main advantage of the adopted algorithm is that it is physically independent of the selected values for the vortex identification in different working modes. Both weak and strong vortices can be identified by setting the same omega value in the whole passage of the reversible pump turbine. Five typical modes（turbine mode, runaway mode, turbine brake mode, zero-flow-rate mode and reverse pump mode） at several typical guide vane openings are selected for the analysis and comparisons. The differences between various modes and different guide vane openings are compared both qualitatively in terms of the vortex distributions and quantitatively in terms of the areas of the vortices in the reversible pump turbines. Our findings indicate that the new omega method could be successfully applied to the vortex identification in the reversible pump turbines.展开更多
This paper presents an extensive survey of the most commonly used tools for diagnosing unbalanced flow in the atmosphere, namely the Lagrangian Rossby number, Psi vector, divergence equation, nonlinear balance equatio...This paper presents an extensive survey of the most commonly used tools for diagnosing unbalanced flow in the atmosphere, namely the Lagrangian Rossby number, Psi vector, divergence equation, nonlinear balance equation, generalized omega-equation, and departure from fields obtained by potential vorticity (PV) inversion. The basic thoery, assumptions as well as implementation and limitations for each of the tools are all discussed. These tools are applied to high—resolution mesoscale model data to assess the role of unbalanced dynamics in the generation of a mesoscale gravity wave event over the East Coast of the United States. Comparison of these tools in this case study shows that these various methods agree to a large extent with each other though they differ in details. Key words Unbalanced flow - Geostrophic adjustment - Gravity waves - Nonlinear balance equation - Potential vorticity inversion - Omega equations - Rossby number This research was conducted under support from NSF grant ATM-9700626 of the United States. The numerical computations described herein were performed on the Cray T90 at the North Carolina Supercomputing Center and the Cray supercomputer at the NCAR Scientific Computing Division, which also provided the initialization fields for the MM5. Thanks are extended to Mark Stoelinga at University of Washington for the RIP post-processing package.展开更多
In this paper,several commonly used vortex identification methods for marine hydrodynamics are revisited.In order to extract and analyse the vortical structures in marine hydrodynamics,the Q,λ2-criterion and modified...In this paper,several commonly used vortex identification methods for marine hydrodynamics are revisited.In order to extract and analyse the vortical structures in marine hydrodynamics,the Q,λ2-criterion and modified normalized Liutex/RortexΩR method are utilized for vortex identification for propeller open water test,ship drag test,ship propeller-rudder interaction,VIV of a marine riser and VIM of a Spar platform.The limitation of Q andλ2-criterion is discussed.The Liutex/RortexΩR method is promising for convenient and accurate vortex identification and visualization.However,care should be taken when choosing the small parameter b0 forΩR.We proposed recommended values of b0 for marine hydrodynamic problems.展开更多
Along with laser-indirect(X-ray)-drive and magnetic-drive target concepts,laser direct drive is a viable approach to achieving ignition and gain with inertial confinement fusion.In the United States,a national program...Along with laser-indirect(X-ray)-drive and magnetic-drive target concepts,laser direct drive is a viable approach to achieving ignition and gain with inertial confinement fusion.In the United States,a national program has been established to demonstrate and understand the physics of laser direct drive.The program utilizes the Omega Laser Facility to conduct implosion and coupling physics at the nominally 30-kJ scale and lasereplasma interaction and coupling physics at the MJ scale at the National Ignition Facility.This article will discuss the motivation and challenges for laser direct drive and the broad-based program presently underway in the United States.展开更多
To determine the replacement of fish oil with vegetable oils in the diet of juvenile Jade perch Scortum barcoo, four feeds with each a different oil （fish, sunflower, linseed and a mixture of 75% canola and 25% linse...To determine the replacement of fish oil with vegetable oils in the diet of juvenile Jade perch Scortum barcoo, four feeds with each a different oil （fish, sunflower, linseed and a mixture of 75% canola and 25% linseed oil）, were fed to Jade perch reared in recirculating aquaculture systems （RAS）. The trial lasted for 10 weeks and the fatty acid （FA） profile of both feed and fish muscle tissue were examined. There was no difference in growth, feed conversion rate （FCR） and mortality. The fish grew from 10 g to 110 g with a FCR of 1.25 and 0 mortality. The FA profile of the fish muscle tissue reflected the FA profile of the feed. The flesh of the fish that were fed the linseed oil diet, were extremely high in omega-3 （n-3） polyunsaturated FA （n-3 PUFA） with 3.75% of wet weight. This is one of the highest concentrations of n-3 PUFA ever recorded in fish flesh. In a finishing feeding test, the remaining vegetable oil fed fish were fed the fish oil diet for another two weeks immediately after the 10 weeks trial, to check for a possible recovery of n-3 highly unsaturated fatty acids （HUFA）. The wash out rate of FA towards n-3 HUFA in the muscle tissue was about 25% over this two weeks period.展开更多
The present paper presents comparisons of the vortex identification between the Omega method and the Q criterion based on the data of a classical flow.From the comparisons of the vortex structure together with the flo...The present paper presents comparisons of the vortex identification between the Omega method and the Q criterion based on the data of a classical flow.From the comparisons of the vortex structure together with the flow statistics,some important conclusions are drawn on the validity of the two methods,as follows.The Omega method can identify various kinds of vortices with different intensities(e.g.,the strong vortex,the medium vortex and the weak vortex).For the Q criterion,due to the subjective threshold selection,only the strong vortex with weak deformations could be identified.Finally,some emerging topics related with the advanced vortex identification methods are briefly discussed.展开更多
In order to obtain the inviscid dendrimers with more terminal amino\|groups than those of ω,ω′\| polyethylene glycol diamine, in the meanwhile to untilize the fine biocompatibility of polyethylene glycol,a series o...In order to obtain the inviscid dendrimers with more terminal amino\|groups than those of ω,ω′\| polyethylene glycol diamine, in the meanwhile to untilize the fine biocompatibility of polyethylene glycol,a series of polyamidoamine dendrimers with polyethylene glycol core were synthesized by Tomalia’s divergent method which invovled a repeated two\|step process:(1) exhaustive Micheal addition of ω,ω′\| polyethylene glycol diamine as the initiating core,with methyl acrylate and (2) exhaustive amidation of the resulting esters with a large excess of ethylenediamine. The structures of all generations of the dendrimer was identified by FT\|IR and elemental analysis, and the numbers of the terminal aminogroups of the integral generations of the dendrimer were determined by potentiometer titration.Although PEG\|NH\-2 and the integral generations had adsorption at ～3300 cm -1 in FT\|IR, the half generations did not have. It indicated that all the steps of Micheal addition took place thoroughly.On the other hand, the conversion of the half generations into their corresponding integral generations made the adsorption of the ester’s carbonyl at 1735～1740cm -1 disappear,it suggested that the conversion was complete.The results of elemental analysis also affirmed the above discussion.However the data of elemental analysis and potentiometer titration of PEG\|5\^0 and PEG\|6\^0 didn’t entirely coincide with their theoretical values,that may be due to the residue of the ingredients such as ethylenediamine which were bundled up by larger generations with more branches and difficult to remove.Except that PEG\|1\^0 and PEG\|2\^0 are solids,the other integral generations are viscous. Influences of the integral generations on coagulation and hemolysis were examined,and the results showed that the properties of coagulation and hemolysis of the integral generations of the dendrimer were similar to those of polyehylene glycol.展开更多
The vortex structure plays a significant role in the investigation of the turbulent drag reduction effect of the viscoelastic turbulent flow.This paper aims to find out an optimal vortex identification method for the ...The vortex structure plays a significant role in the investigation of the turbulent drag reduction effect of the viscoelastic turbulent flow.This paper aims to find out an optimal vortex identification method for the viscoelastic turbulent flows,and then studies the turbulent drag reduction mechanism by analyzing the characteristics of the identified vortex structures in the turbulent flows of the viscoelastic fluids.The Q,λ2,Liutex,Omega(Ω)and Omega-Liutex(ΩR)methods are adopted for the identification of vortex structures in the forced homogeneous isotropic turbulence(FHIT)with/without the polymer additive,respectively.The comparison among these five methods shows that the threshold values for the Q,λ2 and Liutex methods should be specially adjusted so as to suitably describe the strong and weak vortex structures in the FHIT of both the Newtonian and viscoelastic fluids,while a fixed threshold value of 0.52 for theΩandΩR methods is effective for both the Newtonian and viscoelastic fluids.The comparison between the identified vortex structures in the FHIT with and without the polymer additive indicates that theΩandΩR methods are more appropriate for the vortex identification because their dimensionless values with a fixed range from 0 to 1 can avoid the effect of the different ranges of the Q,λ2 and∣R∣(for the Liutex method)for the Newtonian and viscoelastic fluids.This also illustrates that theΩandΩR methods can be extended to identify the vortex structures in the turbulent flow of the viscoelastic fluid.Finally,the characteristics of the vortex structures in the FHIT of the viscoelastic fluid are analyzed by utilizing theΩandΩR methods.The results show that both the strong and weak vortex structures are inhibited by increasing the concentration of the polymer solution and by decreasing the Weissenberg number,especially for the weak vortex structures.展开更多
Bronchial asthma is a chronic inflammatory disease. Allergies are intensely related to bronchial asthma and to other respiratory diseases such as chronic sinusitis, middle ear infections, and nasal polyps. Treatment c...Bronchial asthma is a chronic inflammatory disease. Allergies are intensely related to bronchial asthma and to other respiratory diseases such as chronic sinusitis, middle ear infections, and nasal polyps. Treatment can vary from inhalers to oral medications to drugs delivered in a nebulizer or breathing machine. Besides, dietary involvement was a significant tool to reduce the severity of many chronic inflammatory diseases including asthma. Randomly assigned, double blind, and placebo controlled 290 adults with mild to moderately persistent bronchial asthma concluded in this study, were subjected to alternating phases of supplementation with omega-3 fatty acids, vitamin C and Zn either singly or in combination. Subjective symptom improvement, pulmonary function, and biochemical tests were carried out at the beginning of the study and at the end of each therapeutic phase. The study findings showed that nearly half of the cases were in age between 18 years to 40 years followed by 29.6 of the cases that fall in age range between 40 years and 60 years. It was clear that all the four supplements (ogema-3 fatty acids, vitamin C and Zn, and combination) contributed more than placebo in reducing the severity of bronchial asthma. However, omega 3 fatty acids and combined supplement significantly contributed in symptomatic improvement (p < 0.05). There was a significant improvement of pulmonary function and sputum inflammatory markers with diet supplementation (p < 0.05). So, the subjects with mild and moderately persistent bronchial asthma may get benefit from their dietary supplementation with omega 3 fatty acids, Zinc and vitamin C. It is evident from this study that omega 3 fatty acids and combined supplementation significantly improved the severity of bronchial asthma.展开更多
文摘A vortex is intuitively recognized as the rotational/swirling motion of fluids,but a rigorous and universally-accepted definition is still not available.Vorticity tube/filament has been regarded equivalent to a vortex since Helmholtz proposed the concepts of vorticity tube/filament in 1858 and the vorticity-based methods can be categorized as the first generation of vortex identification methods.During the last three decades,a lot of vortex identification methods,including 0,A,and Aci criteria,have been proposed to overcome the problems associated with the vorticity-based methods.Most of these criteria are based on the Cauchy-Stokes decomposition and/or eigenvalues of the velocity gradient tensor and can be considered as the second generation of vortex identification methods.Starting from 2014,the Vortex and Turbulence Research Team at the University of Texas at Arlington(the UTA team)focus on the development of a new generation of vortex identification methods.The first fruit of this effort,a new Omega(/2)vortex identification method,which defined a vortex as a connected region where the vorticity overtakes the deformation,was published in 2016.In 2017 and 2018,a Liutex(previously called Rortex)vector was proposed to provide a mathematical definition of the local rigid rotation part of the fluid motion,including both the local rotational axis and the rotational strength.Liutex/Rortex is a new physical quantity with scalar,vector and tensor forms exactly representing the local rigid rotation of fluids.Meanwhile,a decomposition of the vorticity to a rotational part namely Liutex/Rortex and an anti-symmetric shear part(RS decomposition)was introduced in 2018,and a universal decomposition of the velocity gradient tensor to a rotation part(7?)and a non-rotation part(NR、was also given in 2018 as a counterpart of the traditional Cauchy-Stokes decomposition.Later in early 2019,a Liutex/Rortex based Omega method called Omega-Liutex,which combines the respective advantages of both Liutex/Rortex and Omega methods,was dev
基金Project supported by the National Key R&D Program of China(Project No.2018YFB0604304-04)the National Natural Science Foundation of China(Grant No.51506051)
文摘Reversible pump turbines are widely employed in the pumped hydro energy storage power plants. The frequent shifts among various operational modes for the reversible pump turbines pose various instability problems, e.g., the strong pressure fluctuation, the shaft swing, and the impeller damage. The instability is related to the vortices generated in the channels of the reversible pump turbines in the generating mode. In the present paper, a new omega vortex identification method is applied to the vortex analysis of the reversible pump turbines. The main advantage of the adopted algorithm is that it is physically independent of the selected values for the vortex identification in different working modes. Both weak and strong vortices can be identified by setting the same omega value in the whole passage of the reversible pump turbine. Five typical modes（turbine mode, runaway mode, turbine brake mode, zero-flow-rate mode and reverse pump mode） at several typical guide vane openings are selected for the analysis and comparisons. The differences between various modes and different guide vane openings are compared both qualitatively in terms of the vortex distributions and quantitatively in terms of the areas of the vortices in the reversible pump turbines. Our findings indicate that the new omega method could be successfully applied to the vortex identification in the reversible pump turbines.
文摘This paper presents an extensive survey of the most commonly used tools for diagnosing unbalanced flow in the atmosphere, namely the Lagrangian Rossby number, Psi vector, divergence equation, nonlinear balance equation, generalized omega-equation, and departure from fields obtained by potential vorticity (PV) inversion. The basic thoery, assumptions as well as implementation and limitations for each of the tools are all discussed. These tools are applied to high—resolution mesoscale model data to assess the role of unbalanced dynamics in the generation of a mesoscale gravity wave event over the East Coast of the United States. Comparison of these tools in this case study shows that these various methods agree to a large extent with each other though they differ in details. Key words Unbalanced flow - Geostrophic adjustment - Gravity waves - Nonlinear balance equation - Potential vorticity inversion - Omega equations - Rossby number This research was conducted under support from NSF grant ATM-9700626 of the United States. The numerical computations described herein were performed on the Cray T90 at the North Carolina Supercomputing Center and the Cray supercomputer at the NCAR Scientific Computing Division, which also provided the initialization fields for the MM5. Thanks are extended to Mark Stoelinga at University of Washington for the RIP post-processing package.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51909160,51879159)the National Key Research and Development Program of China(Grant Nos.2019YFB1704200,2019YFC0312400)+2 种基金This work was supported by the Chang Jiang Scholars Program(Grant No.T2014099)the Shanghai Excellent Academic Leaders Program(Grant No.17XD1402300)the Innovative Special Project of Numerical Tank of Ministry of Industry and Information Technology of China(2016-23/09).
文摘In this paper,several commonly used vortex identification methods for marine hydrodynamics are revisited.In order to extract and analyse the vortical structures in marine hydrodynamics,the Q,λ2-criterion and modified normalized Liutex/RortexΩR method are utilized for vortex identification for propeller open water test,ship drag test,ship propeller-rudder interaction,VIV of a marine riser and VIM of a Spar platform.The limitation of Q andλ2-criterion is discussed.The Liutex/RortexΩR method is promising for convenient and accurate vortex identification and visualization.However,care should be taken when choosing the small parameter b0 forΩR.We proposed recommended values of b0 for marine hydrodynamic problems.
文摘Along with laser-indirect(X-ray)-drive and magnetic-drive target concepts,laser direct drive is a viable approach to achieving ignition and gain with inertial confinement fusion.In the United States,a national program has been established to demonstrate and understand the physics of laser direct drive.The program utilizes the Omega Laser Facility to conduct implosion and coupling physics at the nominally 30-kJ scale and lasereplasma interaction and coupling physics at the MJ scale at the National Ignition Facility.This article will discuss the motivation and challenges for laser direct drive and the broad-based program presently underway in the United States.
文摘To determine the replacement of fish oil with vegetable oils in the diet of juvenile Jade perch Scortum barcoo, four feeds with each a different oil （fish, sunflower, linseed and a mixture of 75% canola and 25% linseed oil）, were fed to Jade perch reared in recirculating aquaculture systems （RAS）. The trial lasted for 10 weeks and the fatty acid （FA） profile of both feed and fish muscle tissue were examined. There was no difference in growth, feed conversion rate （FCR） and mortality. The fish grew from 10 g to 110 g with a FCR of 1.25 and 0 mortality. The FA profile of the fish muscle tissue reflected the FA profile of the feed. The flesh of the fish that were fed the linseed oil diet, were extremely high in omega-3 （n-3） polyunsaturated FA （n-3 PUFA） with 3.75% of wet weight. This is one of the highest concentrations of n-3 PUFA ever recorded in fish flesh. In a finishing feeding test, the remaining vegetable oil fed fish were fed the fish oil diet for another two weeks immediately after the 10 weeks trial, to check for a possible recovery of n-3 highly unsaturated fatty acids （HUFA）. The wash out rate of FA towards n-3 HUFA in the muscle tissue was about 25% over this two weeks period.
文摘The present paper presents comparisons of the vortex identification between the Omega method and the Q criterion based on the data of a classical flow.From the comparisons of the vortex structure together with the flow statistics,some important conclusions are drawn on the validity of the two methods,as follows.The Omega method can identify various kinds of vortices with different intensities(e.g.,the strong vortex,the medium vortex and the weak vortex).For the Q criterion,due to the subjective threshold selection,only the strong vortex with weak deformations could be identified.Finally,some emerging topics related with the advanced vortex identification methods are briefly discussed.
文摘In order to obtain the inviscid dendrimers with more terminal amino\|groups than those of ω,ω′\| polyethylene glycol diamine, in the meanwhile to untilize the fine biocompatibility of polyethylene glycol,a series of polyamidoamine dendrimers with polyethylene glycol core were synthesized by Tomalia’s divergent method which invovled a repeated two\|step process:(1) exhaustive Micheal addition of ω,ω′\| polyethylene glycol diamine as the initiating core,with methyl acrylate and (2) exhaustive amidation of the resulting esters with a large excess of ethylenediamine. The structures of all generations of the dendrimer was identified by FT\|IR and elemental analysis, and the numbers of the terminal aminogroups of the integral generations of the dendrimer were determined by potentiometer titration.Although PEG\|NH\-2 and the integral generations had adsorption at ～3300 cm -1 in FT\|IR, the half generations did not have. It indicated that all the steps of Micheal addition took place thoroughly.On the other hand, the conversion of the half generations into their corresponding integral generations made the adsorption of the ester’s carbonyl at 1735～1740cm -1 disappear,it suggested that the conversion was complete.The results of elemental analysis also affirmed the above discussion.However the data of elemental analysis and potentiometer titration of PEG\|5\^0 and PEG\|6\^0 didn’t entirely coincide with their theoretical values,that may be due to the residue of the ingredients such as ethylenediamine which were bundled up by larger generations with more branches and difficult to remove.Except that PEG\|1\^0 and PEG\|2\^0 are solids,the other integral generations are viscous. Influences of the integral generations on coagulation and hemolysis were examined,and the results showed that the properties of coagulation and hemolysis of the integral generations of the dendrimer were similar to those of polyehylene glycol.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51706050,51806051).
文摘The vortex structure plays a significant role in the investigation of the turbulent drag reduction effect of the viscoelastic turbulent flow.This paper aims to find out an optimal vortex identification method for the viscoelastic turbulent flows,and then studies the turbulent drag reduction mechanism by analyzing the characteristics of the identified vortex structures in the turbulent flows of the viscoelastic fluids.The Q,λ2,Liutex,Omega(Ω)and Omega-Liutex(ΩR)methods are adopted for the identification of vortex structures in the forced homogeneous isotropic turbulence(FHIT)with/without the polymer additive,respectively.The comparison among these five methods shows that the threshold values for the Q,λ2 and Liutex methods should be specially adjusted so as to suitably describe the strong and weak vortex structures in the FHIT of both the Newtonian and viscoelastic fluids,while a fixed threshold value of 0.52 for theΩandΩR methods is effective for both the Newtonian and viscoelastic fluids.The comparison between the identified vortex structures in the FHIT with and without the polymer additive indicates that theΩandΩR methods are more appropriate for the vortex identification because their dimensionless values with a fixed range from 0 to 1 can avoid the effect of the different ranges of the Q,λ2 and∣R∣(for the Liutex method)for the Newtonian and viscoelastic fluids.This also illustrates that theΩandΩR methods can be extended to identify the vortex structures in the turbulent flow of the viscoelastic fluid.Finally,the characteristics of the vortex structures in the FHIT of the viscoelastic fluid are analyzed by utilizing theΩandΩR methods.The results show that both the strong and weak vortex structures are inhibited by increasing the concentration of the polymer solution and by decreasing the Weissenberg number,especially for the weak vortex structures.
文摘Bronchial asthma is a chronic inflammatory disease. Allergies are intensely related to bronchial asthma and to other respiratory diseases such as chronic sinusitis, middle ear infections, and nasal polyps. Treatment can vary from inhalers to oral medications to drugs delivered in a nebulizer or breathing machine. Besides, dietary involvement was a significant tool to reduce the severity of many chronic inflammatory diseases including asthma. Randomly assigned, double blind, and placebo controlled 290 adults with mild to moderately persistent bronchial asthma concluded in this study, were subjected to alternating phases of supplementation with omega-3 fatty acids, vitamin C and Zn either singly or in combination. Subjective symptom improvement, pulmonary function, and biochemical tests were carried out at the beginning of the study and at the end of each therapeutic phase. The study findings showed that nearly half of the cases were in age between 18 years to 40 years followed by 29.6 of the cases that fall in age range between 40 years and 60 years. It was clear that all the four supplements (ogema-3 fatty acids, vitamin C and Zn, and combination) contributed more than placebo in reducing the severity of bronchial asthma. However, omega 3 fatty acids and combined supplement significantly contributed in symptomatic improvement (p < 0.05). There was a significant improvement of pulmonary function and sputum inflammatory markers with diet supplementation (p < 0.05). So, the subjects with mild and moderately persistent bronchial asthma may get benefit from their dietary supplementation with omega 3 fatty acids, Zinc and vitamin C. It is evident from this study that omega 3 fatty acids and combined supplementation significantly improved the severity of bronchial asthma.
