Lumbar spine stenosis(LSS)is a narrowing of the spinal canal that results in pressure on the spinal nerves.This orthopedic disorder can cause severe pain and dysfunction.LSS is a common disabling problem amongst elder...Lumbar spine stenosis(LSS)is a narrowing of the spinal canal that results in pressure on the spinal nerves.This orthopedic disorder can cause severe pain and dysfunction.LSS is a common disabling problem amongst elderly people.In this paper,we developed a finite element model(FEM)to study the forces and the von Mises stress acting on the spine when people bend down.An artificial lumbar spine(L3)was generated from CT data by using the FEM,which is a powerful tool to study biomechanics.The proposed model is able to predict the effect of forces which apply to the lumbar spine.In addition,FEM allows us to investigate the tests into the lumbar spine instead of applying the tests to the real spine in humans.The proposed model is highly accurate and provides precise information about the lumbar spine(L3).We investigate the behavior of humans in daily life which effects to the lumbar spine in a normal person and a patient with LSS.The computational results revealed high displacement levels around the spinal canal and lower displacement levels in the spinal body when bending down.The total displacement of the axial load in a normal person was higher when compared with patients with LSS.Higher degree bends resulted in a lower total displacement when compared with lower degree bends,while the von Mises stress decreased as the bending degree increased.展开更多
In this paper,we developed a mathematical model for Streptococcus suis,which is an epidemic by considering the moisture that affects the infection.The disease is caused by Streptococcus suis infection found in pigs wh...In this paper,we developed a mathematical model for Streptococcus suis,which is an epidemic by considering the moisture that affects the infection.The disease is caused by Streptococcus suis infection found in pigs which can be transmitted to humans.The patients of Streptococcus suis were generally found in adults males and the elderly who contacted pigs or who ate uncooked pork.In human cases,the infection can cause a severe illness and death.This disease has an impact to the financial losses in the swine industry.In the development of models for this disease,we have divided the population into 7 related groups which are susceptible pig compartment,infected pig compartment,quarantined pig compartment,recovered pig compartment,susceptible human compartment,infected human compartment,and recovered human compartment.After that,we use this model and a quarantine strategy to analyze the spread of the infection.In addition,the basic reproduction number R0 is determined by using the next-generation matrix which can analyze the stability of the model.The numerical simulations of the proposed model are illustrated to confirm the results from theorems.The results showed that there is an effect from moisture to the disease transmission.When the moisture increases the disease infection also increases.展开更多
基金This research was supported by the Basic Research Fund of Khon Kaen University.This research was also financially supported by Mahasarakham University。
文摘Lumbar spine stenosis(LSS)is a narrowing of the spinal canal that results in pressure on the spinal nerves.This orthopedic disorder can cause severe pain and dysfunction.LSS is a common disabling problem amongst elderly people.In this paper,we developed a finite element model(FEM)to study the forces and the von Mises stress acting on the spine when people bend down.An artificial lumbar spine(L3)was generated from CT data by using the FEM,which is a powerful tool to study biomechanics.The proposed model is able to predict the effect of forces which apply to the lumbar spine.In addition,FEM allows us to investigate the tests into the lumbar spine instead of applying the tests to the real spine in humans.The proposed model is highly accurate and provides precise information about the lumbar spine(L3).We investigate the behavior of humans in daily life which effects to the lumbar spine in a normal person and a patient with LSS.The computational results revealed high displacement levels around the spinal canal and lower displacement levels in the spinal body when bending down.The total displacement of the axial load in a normal person was higher when compared with patients with LSS.Higher degree bends resulted in a lower total displacement when compared with lower degree bends,while the von Mises stress decreased as the bending degree increased.
文摘In this paper,we developed a mathematical model for Streptococcus suis,which is an epidemic by considering the moisture that affects the infection.The disease is caused by Streptococcus suis infection found in pigs which can be transmitted to humans.The patients of Streptococcus suis were generally found in adults males and the elderly who contacted pigs or who ate uncooked pork.In human cases,the infection can cause a severe illness and death.This disease has an impact to the financial losses in the swine industry.In the development of models for this disease,we have divided the population into 7 related groups which are susceptible pig compartment,infected pig compartment,quarantined pig compartment,recovered pig compartment,susceptible human compartment,infected human compartment,and recovered human compartment.After that,we use this model and a quarantine strategy to analyze the spread of the infection.In addition,the basic reproduction number R0 is determined by using the next-generation matrix which can analyze the stability of the model.The numerical simulations of the proposed model are illustrated to confirm the results from theorems.The results showed that there is an effect from moisture to the disease transmission.When the moisture increases the disease infection also increases.
