Based on patient computerized tomography data,we segmented a region containing an intracranial hematoma using the threshold method and reconstructed the 3D hematoma model.To improve the efficiency and accuracy of iden...Based on patient computerized tomography data,we segmented a region containing an intracranial hematoma using the threshold method and reconstructed the 3D hematoma model.To improve the efficiency and accuracy of identifying puncture points,a point-cloud search arithmetic method for modified adaptive weighted particle swarm optimization is proposed and used for optimal external axis extraction.According to the characteristics of the multitube drainage tube and the clinical needs of puncture for intracranial hematoma removal,the proposed algorithm can provide an optimal route for a drainage tube for the hematoma,the precise position of the puncture point,and preoperative planning information,which have considerable instructional significance for clinicians.展开更多
The period-3 behaviors of 105 exons from 20 genes in human were studied by Fourier power spectrum. The results indicated that not all exons show the period-3 behavior. The exons were adjusted in order to make them acc...The period-3 behaviors of 105 exons from 20 genes in human were studied by Fourier power spectrum. The results indicated that not all exons show the period-3 behavior. The exons were adjusted in order to make them accord with the order of the protein translated, and we found that the period-3 character is relation to the length of exons and the bases distribution in the three codon position. Furthermore, as long as the exons with period-3 behavior accord with the order of protein translated, they would exhibit the synonymous codons usage preference, and the codons with g/c at the third position are used in higher frequency. The results are significant to the gene prediction and the research on the introns.展开更多
Gyllenberg and Yan(Discrete Contin Dyn Syst Ser B 11(2):347–352,2009)presented a system in Zeeman’s class 30 of 3-dimensional Lotka-Volterra(3D LV)competitive systems to admit at least two limit cycles,one of which ...Gyllenberg and Yan(Discrete Contin Dyn Syst Ser B 11(2):347–352,2009)presented a system in Zeeman’s class 30 of 3-dimensional Lotka-Volterra(3D LV)competitive systems to admit at least two limit cycles,one of which is generated by the Hopf bifurcation and the other is obtained by the Poincaré-Bendixson theorem.Yu et al.(J Math Anal Appl 436:521–555,2016,Sect.3.4)recalculated the first Liapunov coefficient of Gyllenberg and Yan’s system to be positive,rather than negative as in Gyllenberg and Yan(2009),and pointed out that the Poincaré-Bendixson theorem is not applicable for that system.Jiang et al.(J Differ Equ 284:183–218,2021,p.213)proposed an open question:“whether Zeeman’s class 30 can be rigorously proved to admit at least two limit cycles by the Hopf theorem and the Poincaré-Bendixson theorem?”This paper provides four systems in Zeeman’s class 30 to admit at least two limit cycles by the Hopf theorem and the Poincaré-Bendixson theorem and gives an answer to the above question.展开更多
The rapid synthesis of 3-bromocarbarole-N-acetic acid was performed using microwave irradiation. Under the optimal conditions the yield was 85.6% . The crystal structure showed that the carboxylic groups form bifurcat...The rapid synthesis of 3-bromocarbarole-N-acetic acid was performed using microwave irradiation. Under the optimal conditions the yield was 85.6% . The crystal structure showed that the carboxylic groups form bifurcated hydrogen bonds and the hydroxyl oxygen atoms serve as proton donors and also acceptor. Each carboxylic group was involved in four hydrogen bonds. The package of crystal was dominated by links of these hydrogen bonds.展开更多
The problem of nonlinear forced oscillations for elliptical sandwich plates is dealt with. Based on the governing equations expressed in terms of five displacement components, the nonlinear dynamic equation of an elli...The problem of nonlinear forced oscillations for elliptical sandwich plates is dealt with. Based on the governing equations expressed in terms of five displacement components, the nonlinear dynamic equation of an elliptical sandwich plate under a harmonic force is derived. A superpositive-iterative harmonic balance (SIHB) method is presented for the steady-state analysis of strongly nonlinear oscillators. In a periodic oscillation, the periodic solutions can be expressed in the form of basic harmonics and bifurcate harmonics. Thus, an oscillation system which is described as a second order ordinary differential equation, can be expressed as fundamental differential equation with fundamental harmonics and incremental differential equation with derived harmonics. The 1/3 subharmonic solution of an elliptical sandwich plate is investigated by using the methods of SIHB. The SIHB method is compared with the numerical integration method. Finally, asymptotical stability of the 1/3 subharmonic oscillations is inspected.展开更多
BACKGROUND Coronary intervention for bifurcation lesions is still challenging for interventional cardiologists.Left main(LM)bifurcation lesions have a higher risk due to the vast blood supply in this area and treatmen...BACKGROUND Coronary intervention for bifurcation lesions is still challenging for interventional cardiologists.Left main(LM)bifurcation lesions have a higher risk due to the vast blood supply in this area and treatment choice is difficult.Ostial compromise of the side branch decreases patient prognosis,and its management is still an issue despite the different strategies and devices available.CASE SUMMARY A 42-year-old male patient was admitted to hospital due to chest pain and syncope.Coronary angiography showed acute LM occlusion.Following thrombus aspiration,a LM bifurcation lesion remained.Coronary angiography was repeated one week later,and at the same time,3D optical coherence tomography(OCT)was carried out to better show the geometry of the bifurcation,which confirmed that the stenosis in the ostial left circumflex artery was caused by a long carina.After assessment of the plaque characteristics and the minimum lumen area,the cross-over strategy,kissing balloon inflation and proximal optimization technique were chosen to treat the bifurcation lesion.A“moving”carina was found twice during the intervention.Good stent apposition and expansion were confirmed by OCT after proximal optimization technique.The three-month follow-up showed good recovery and normal cardiac function.CONCLUSION 3D-OCT can facilitate decision-making for coronary interventions in patients with critical bifurcation lesions.展开更多
We consider perturbations which may or may not depend explicitly on time for the three-dimensional homoclinic systems. We obtain the existence and bifurcation theorems for transversal homoclinic points and homoclinic ...We consider perturbations which may or may not depend explicitly on time for the three-dimensional homoclinic systems. We obtain the existence and bifurcation theorems for transversal homoclinic points and homoclinic orbits, and illustrate our results with two examples.展开更多
In this paper, we use a qualitative method to study global and local bifurcations in a disturbedHamiltonian vector field approaching a Poincare map in the 3:1 resonant case. We give explicitcalculation formulas to det...In this paper, we use a qualitative method to study global and local bifurcations in a disturbedHamiltonian vector field approaching a Poincare map in the 3:1 resonant case. We give explicitcalculation formulas to determine bifurcation parameters and draw various bifurcations and phaseportraits in the phase plane.展开更多
In this paper,the third model of four(3+1)-dimensional nonlinear evolution equations,generated by the Jaulent-Miodek hierarchy,is investigated by the bifurcation method of planar dynamical systems.The 2-parameters dif...In this paper,the third model of four(3+1)-dimensional nonlinear evolution equations,generated by the Jaulent-Miodek hierarchy,is investigated by the bifurcation method of planar dynamical systems.The 2-parameters different bifurcation regions are obtained.According to the different phase portraits in 2-parameters different bifurcation regions,we obtain kink(anti-kink)wave solutions,solitary wave solutions and periodic wave solutions for the third of these models in the different subsets of 4-parameters space by dynamical system method.Furthermore,the explicit exact expressions of these bounded traveling waves are obtained.All these wave solutions are characterized by distinct physical structures.展开更多
基金funded by the National Science Foundation of China,Nos.51674121 and 61702184the Returned Overseas Scholar Funding of Hebei Province,No.C2015005014the Hebei Key Laboratory of Science and Application,and Tangshan Innovation Team Project,No.18130209B.
文摘Based on patient computerized tomography data,we segmented a region containing an intracranial hematoma using the threshold method and reconstructed the 3D hematoma model.To improve the efficiency and accuracy of identifying puncture points,a point-cloud search arithmetic method for modified adaptive weighted particle swarm optimization is proposed and used for optimal external axis extraction.According to the characteristics of the multitube drainage tube and the clinical needs of puncture for intracranial hematoma removal,the proposed algorithm can provide an optimal route for a drainage tube for the hematoma,the precise position of the puncture point,and preoperative planning information,which have considerable instructional significance for clinicians.
基金This work was supported by the National Natural Science Foundation of China(Grants 20475068)the Natural Science Foundation of Guangdong Province(Contact No.031577)the Opening Foundation of State Key Laboratory of Chem/Biosensing and Chemometrics of Hunan University(2003).
文摘The period-3 behaviors of 105 exons from 20 genes in human were studied by Fourier power spectrum. The results indicated that not all exons show the period-3 behavior. The exons were adjusted in order to make them accord with the order of the protein translated, and we found that the period-3 character is relation to the length of exons and the bases distribution in the three codon position. Furthermore, as long as the exons with period-3 behavior accord with the order of protein translated, they would exhibit the synonymous codons usage preference, and the codons with g/c at the third position are used in higher frequency. The results are significant to the gene prediction and the research on the introns.
基金the National Natural Science Foundation of China(NSFC)under Grant No.12171321.
文摘Gyllenberg and Yan(Discrete Contin Dyn Syst Ser B 11(2):347–352,2009)presented a system in Zeeman’s class 30 of 3-dimensional Lotka-Volterra(3D LV)competitive systems to admit at least two limit cycles,one of which is generated by the Hopf bifurcation and the other is obtained by the Poincaré-Bendixson theorem.Yu et al.(J Math Anal Appl 436:521–555,2016,Sect.3.4)recalculated the first Liapunov coefficient of Gyllenberg and Yan’s system to be positive,rather than negative as in Gyllenberg and Yan(2009),and pointed out that the Poincaré-Bendixson theorem is not applicable for that system.Jiang et al.(J Differ Equ 284:183–218,2021,p.213)proposed an open question:“whether Zeeman’s class 30 can be rigorously proved to admit at least two limit cycles by the Hopf theorem and the Poincaré-Bendixson theorem?”This paper provides four systems in Zeeman’s class 30 to admit at least two limit cycles by the Hopf theorem and the Poincaré-Bendixson theorem and gives an answer to the above question.
文摘The rapid synthesis of 3-bromocarbarole-N-acetic acid was performed using microwave irradiation. Under the optimal conditions the yield was 85.6% . The crystal structure showed that the carboxylic groups form bifurcated hydrogen bonds and the hydroxyl oxygen atoms serve as proton donors and also acceptor. Each carboxylic group was involved in four hydrogen bonds. The package of crystal was dominated by links of these hydrogen bonds.
文摘The problem of nonlinear forced oscillations for elliptical sandwich plates is dealt with. Based on the governing equations expressed in terms of five displacement components, the nonlinear dynamic equation of an elliptical sandwich plate under a harmonic force is derived. A superpositive-iterative harmonic balance (SIHB) method is presented for the steady-state analysis of strongly nonlinear oscillators. In a periodic oscillation, the periodic solutions can be expressed in the form of basic harmonics and bifurcate harmonics. Thus, an oscillation system which is described as a second order ordinary differential equation, can be expressed as fundamental differential equation with fundamental harmonics and incremental differential equation with derived harmonics. The 1/3 subharmonic solution of an elliptical sandwich plate is investigated by using the methods of SIHB. The SIHB method is compared with the numerical integration method. Finally, asymptotical stability of the 1/3 subharmonic oscillations is inspected.
基金Supported by National Natural Science Foundation of China,No.81570360Beijing Lisheng Cardiovascular Grant,No.LHJJ201612425
文摘BACKGROUND Coronary intervention for bifurcation lesions is still challenging for interventional cardiologists.Left main(LM)bifurcation lesions have a higher risk due to the vast blood supply in this area and treatment choice is difficult.Ostial compromise of the side branch decreases patient prognosis,and its management is still an issue despite the different strategies and devices available.CASE SUMMARY A 42-year-old male patient was admitted to hospital due to chest pain and syncope.Coronary angiography showed acute LM occlusion.Following thrombus aspiration,a LM bifurcation lesion remained.Coronary angiography was repeated one week later,and at the same time,3D optical coherence tomography(OCT)was carried out to better show the geometry of the bifurcation,which confirmed that the stenosis in the ostial left circumflex artery was caused by a long carina.After assessment of the plaque characteristics and the minimum lumen area,the cross-over strategy,kissing balloon inflation and proximal optimization technique were chosen to treat the bifurcation lesion.A“moving”carina was found twice during the intervention.Good stent apposition and expansion were confirmed by OCT after proximal optimization technique.The three-month follow-up showed good recovery and normal cardiac function.CONCLUSION 3D-OCT can facilitate decision-making for coronary interventions in patients with critical bifurcation lesions.
文摘We consider perturbations which may or may not depend explicitly on time for the three-dimensional homoclinic systems. We obtain the existence and bifurcation theorems for transversal homoclinic points and homoclinic orbits, and illustrate our results with two examples.
基金The project supported by the National Natural Science Foundation of China
文摘In this paper, we use a qualitative method to study global and local bifurcations in a disturbedHamiltonian vector field approaching a Poincare map in the 3:1 resonant case. We give explicitcalculation formulas to determine bifurcation parameters and draw various bifurcations and phaseportraits in the phase plane.
基金the National Natural Science Foundation of China through Grant No.11772007the Natural Science Foundation of Beijing through Grant No.1172002+2 种基金the International Science and Technology Cooperation Program of China through Grant No.2014DFR61080the Research Fund for Higher Education of Gansu No.2018B-48the Research Fund for 13th Five-Year Plan for Educational Science of Gansu No.GS[2018]GHBBK072.
文摘In this paper,the third model of four(3+1)-dimensional nonlinear evolution equations,generated by the Jaulent-Miodek hierarchy,is investigated by the bifurcation method of planar dynamical systems.The 2-parameters different bifurcation regions are obtained.According to the different phase portraits in 2-parameters different bifurcation regions,we obtain kink(anti-kink)wave solutions,solitary wave solutions and periodic wave solutions for the third of these models in the different subsets of 4-parameters space by dynamical system method.Furthermore,the explicit exact expressions of these bounded traveling waves are obtained.All these wave solutions are characterized by distinct physical structures.