We study the feasibility of endoscopic optical Doppler tomography with a micro-electro-mechanical system(MEMS) mirror based probe. The additional phase shifts introduced by the probe are tracked and formulated.The sup...We study the feasibility of endoscopic optical Doppler tomography with a micro-electro-mechanical system(MEMS) mirror based probe. The additional phase shifts introduced by the probe are tracked and formulated.The suppression method of the probe phase shifts is proposed and validated by fluid flow detection experiments.In vivo blood flow detection is also implemented on a hairless mouse. The velocities of the blood flow in two directions are obtained to be-8.1 mm/s and 6.6 mm/s, respectively.展开更多
The optical rotational Doppler effect associated with orbital angular momentum provides a new means for rotational velocity detection.In this paper,we investigate the influence of atmospheric turbulence on the rotatio...The optical rotational Doppler effect associated with orbital angular momentum provides a new means for rotational velocity detection.In this paper,we investigate the influence of atmospheric turbulence on the rotational Doppler effect.First,we deduce the generalized formula of the rotational Doppler shift in atmospheric turbulence by mode decomposition.It is found that the rotational Doppler signal frequency spectrum will be broadened,and the bandwidth is related to the turbulence intensity.In addition,as the propagation distance increases,the bandwidth also increases.And when C_(n)^(2)≤5×10^(-15)m^(-2/3)and 2z≤2 km,the rotational Doppler signal frequency spectrum width d and the spiral spectrum width d_(0)satisfy the relationship d=2d_(0-1).Finally,we analyze the influence of mode crosstalk on the rotational Doppler effect,and the results show that it destroys the symmetrical distribution of the rotational Doppler spectrum about 2l·Ω/2π.This theoretical model enables us to better understand the generation of the rotational Doppler frequency and may help us better analyze the influence of the complex atmospheric environment on the rotational Doppler frequency.展开更多
Acute tubular necrosis(ATN)induced by ischemia is the most common insult to donor kidneysdestined for trarsplantation.ATN results from sweling and subsequent damage to cells lining thelkidney tubules.In this study,we ...Acute tubular necrosis(ATN)induced by ischemia is the most common insult to donor kidneysdestined for trarsplantation.ATN results from sweling and subsequent damage to cells lining thelkidney tubules.In this study,we demonstrate the capability of optical coherence tomography(OcT)to image the renal microst ructures of living human donor kidneys and potentially providea measure to det ermine the extent of A TN.We also found that Doppler-based OCT(i.e.,DOCT)reveals renal blood flow dynamics that is another major factor which could relate to post-transplant renal finction.All OCT/DoCT oberva tions were performed in a noninvasive,sterileand timely manner on intact human kidneys both prior to(er vivo)and following(in vivo)theirtransplantation.Our results indicate that this imaging model provides transplant surgeons withan objective visualization of the transplant lidneys prior and immediately post transplantation.展开更多
An iterative physical optics（IPO） model is proposed to solve extra large scale electric electromagnetic（EM） scattering from randomly rough surfaces. In order to accelerate the convergence of the IPO model, the for...An iterative physical optics（IPO） model is proposed to solve extra large scale electric electromagnetic（EM） scattering from randomly rough surfaces. In order to accelerate the convergence of the IPO model, the forward-backward methodology and its modification with underrelaxation iteration are developed to simulate the rough surface scattering; the local iteration methodology and the fast far field approximation（Fa FFA） in the matrix-vector product are proposed to reduce greatly the computational complexity. These techniques make Monte Carlo simulations possible. Thus, the average Doppler spectra of backscattered signals obtained from the simulations are compared for different incident angles and sea states. In particular, the simulations show a broadening of the Doppler spectra for a more complicated sea state at a low grazing angle（LGA）.展开更多
In order to overcome the adverse effects of Doppler wavelength shift on data transmission in the optical satellite networks,a dynamic routing and wavelength assignment algorithm based on crosslayer design( CL-DRWA) is...In order to overcome the adverse effects of Doppler wavelength shift on data transmission in the optical satellite networks,a dynamic routing and wavelength assignment algorithm based on crosslayer design( CL-DRWA) is introduced which can improve robustness of the network. Above all,a cross-layer optimization model is designed,which considers transmission delay and wavelength-continuity constraint,as well as Doppler wavelength shift. Then CL-DRWA is applied to solve this model,resulting in finding an optimal light path satisfying the above constraints for every connection request. In CL-DRWA,Bellman-Ford method is used to find an optimal route and a distributed relative capacity loss method is implemented to get an optimal wavelength assignment result on the optimal route. Moreover,compared with the dynamic routing and wavelength assignment algorithm based on minimum delay strategy( MD-DRWA),CL-DRWA can make an improvement of 5. 3% on the communication success probability. Meanwhile,CL-DRWA can meet the requirement of transmission delay for real-time services.展开更多
Cancer(malignant tumor)is one of the serious threats to human life,causing 13%of all human deaths.A crucial step in the metastasis cascade of cancer is hematogenous spreading of tumor cells from a primary tumor.Thus,i...Cancer(malignant tumor)is one of the serious threats to human life,causing 13%of all human deaths.A crucial step in the metastasis cascade of cancer is hematogenous spreading of tumor cells from a primary tumor.Thus,isolation and identification of cells that have detached from the primary tumor and circulating in the bloodstream(circulating tumor cells,CTCs)is considered to be a potential alternation to detect,characterize,and monitor cancer.Current methods for isolating CTCs are limited to complex analytic approaches that generate very low yield and purity.Here,we propose a high throughput 3D structured microfluidic chip integrated with surface plasmon resonance(SPR)sensor to isolate and identify CTCs from peripheral whole blood sample.The microfluidic velocity-field within the channel of the chip is mediated by an array of microposts protruding from upper surface of the channel.The height of microposts is shorter than that of the channel,forming a gap between the microposts and the lower surface of the channel.The lower surface of the channel also acts as the SPR sensor which can be used to identify isolated CTCs.Microfluidic velocity-field under different parameters of the arrayed microposts is studied through numerical simulation based on finite element method.Measurement on one of such fabricated microchips is conducted by our established optical Doppler tomography technique benefiting from its noninvasive,noncontact,and high-resolution spatialresolved capabilities.Both simulation and measurement of the microfluidic velocity-field within the structured channel demonstrates that it is feasible to introduce fluidic mixing and causes perpendicular flow component to the lower surface of the channel by the 3D structured microposts.Such mixing and approaching capabilities are especially desirable for isolation and identification of CTCs at the coated SPR sensor.展开更多
In experiments on newbom rats with stress related intracrani al hemorhage(ICH)using Doppler optical coberence tomognaphy(DOCT)we have shown that latent stage of ICH(4 h after stress)is characterized by decrease of ven...In experiments on newbom rats with stress related intracrani al hemorhage(ICH)using Doppler optical coberence tomognaphy(DOCT)we have shown that latent stage of ICH(4 h after stress)is characterized by decrease of venous blood outflow and the loss of sensitivity of sagittal vein to vasoconstrictor ffect of adrenaline.The incidence of ICH(24 h after stress)was accompanied by progressi on of early pathological changes in cerebral venous blood flow(CVBF)and development of venous insufficiency.Taking into consideration of this fact,we suggest that the suppression of CVBF related to the severity to the deleterious effect of stress on the brain hemodynamics in newborn rats.These facts allow us to conclude that the venous insufficiency with the loss of vasoconstrictor response to adrenaline is an informative and sensitive component of pattern of CVBF that can be important diagnostic criteria of risk of ICH development in newborns.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 61705199the Natural Science Foundation of Henan Province under Grant No 162300410317+2 种基金the Henan Science and Technology Project under Grant Nos 162102310576and 172102210542the Zhengzhou Science and Technology Project under Grant No 153PKJGG125the US National Science Foundation under Grant No 1002209
文摘We study the feasibility of endoscopic optical Doppler tomography with a micro-electro-mechanical system(MEMS) mirror based probe. The additional phase shifts introduced by the probe are tracked and formulated.The suppression method of the probe phase shifts is proposed and validated by fluid flow detection experiments.In vivo blood flow detection is also implemented on a hairless mouse. The velocities of the blood flow in two directions are obtained to be-8.1 mm/s and 6.6 mm/s, respectively.
基金Project supported by the Research Plan Project of the National University of Defense Technology(Grant No.ZK18-0102)the National Natural Science Foundation of China(Grant No.61871389)+1 种基金the State Key Laboratory of Pulsed Power Laser Technology(Grant No.KY21C604)the Postgraduate Scientific Research Innovation Project of Hunan Province(Grant Nos.CX20220007 and CX20230024)。
文摘The optical rotational Doppler effect associated with orbital angular momentum provides a new means for rotational velocity detection.In this paper,we investigate the influence of atmospheric turbulence on the rotational Doppler effect.First,we deduce the generalized formula of the rotational Doppler shift in atmospheric turbulence by mode decomposition.It is found that the rotational Doppler signal frequency spectrum will be broadened,and the bandwidth is related to the turbulence intensity.In addition,as the propagation distance increases,the bandwidth also increases.And when C_(n)^(2)≤5×10^(-15)m^(-2/3)and 2z≤2 km,the rotational Doppler signal frequency spectrum width d and the spiral spectrum width d_(0)satisfy the relationship d=2d_(0-1).Finally,we analyze the influence of mode crosstalk on the rotational Doppler effect,and the results show that it destroys the symmetrical distribution of the rotational Doppler spectrum about 2l·Ω/2π.This theoretical model enables us to better understand the generation of the rotational Doppler frequency and may help us better analyze the influence of the complex atmospheric environment on the rotational Doppler frequency.
文摘Acute tubular necrosis(ATN)induced by ischemia is the most common insult to donor kidneysdestined for trarsplantation.ATN results from sweling and subsequent damage to cells lining thelkidney tubules.In this study,we demonstrate the capability of optical coherence tomography(OcT)to image the renal microst ructures of living human donor kidneys and potentially providea measure to det ermine the extent of A TN.We also found that Doppler-based OCT(i.e.,DOCT)reveals renal blood flow dynamics that is another major factor which could relate to post-transplant renal finction.All OCT/DoCT oberva tions were performed in a noninvasive,sterileand timely manner on intact human kidneys both prior to(er vivo)and following(in vivo)theirtransplantation.Our results indicate that this imaging model provides transplant surgeons withan objective visualization of the transplant lidneys prior and immediately post transplantation.
基金supported by the National Natural Science Foundation of China(61372033)
文摘An iterative physical optics（IPO） model is proposed to solve extra large scale electric electromagnetic（EM） scattering from randomly rough surfaces. In order to accelerate the convergence of the IPO model, the forward-backward methodology and its modification with underrelaxation iteration are developed to simulate the rough surface scattering; the local iteration methodology and the fast far field approximation（Fa FFA） in the matrix-vector product are proposed to reduce greatly the computational complexity. These techniques make Monte Carlo simulations possible. Thus, the average Doppler spectra of backscattered signals obtained from the simulations are compared for different incident angles and sea states. In particular, the simulations show a broadening of the Doppler spectra for a more complicated sea state at a low grazing angle（LGA）.
基金Supported by the National Natural Science Foundation of China(No.61675033,61575026,61675232,61571440)the National High Technology Research and Development Program of China(No.2015AA015504)
文摘In order to overcome the adverse effects of Doppler wavelength shift on data transmission in the optical satellite networks,a dynamic routing and wavelength assignment algorithm based on crosslayer design( CL-DRWA) is introduced which can improve robustness of the network. Above all,a cross-layer optimization model is designed,which considers transmission delay and wavelength-continuity constraint,as well as Doppler wavelength shift. Then CL-DRWA is applied to solve this model,resulting in finding an optimal light path satisfying the above constraints for every connection request. In CL-DRWA,Bellman-Ford method is used to find an optimal route and a distributed relative capacity loss method is implemented to get an optimal wavelength assignment result on the optimal route. Moreover,compared with the dynamic routing and wavelength assignment algorithm based on minimum delay strategy( MD-DRWA),CL-DRWA can make an improvement of 5. 3% on the communication success probability. Meanwhile,CL-DRWA can meet the requirement of transmission delay for real-time services.
基金supported by National High Technology Research and Development Program of China(2006AA02Z4E0)Natural Science Foundation of China(60878057,60978037).
文摘Cancer(malignant tumor)is one of the serious threats to human life,causing 13%of all human deaths.A crucial step in the metastasis cascade of cancer is hematogenous spreading of tumor cells from a primary tumor.Thus,isolation and identification of cells that have detached from the primary tumor and circulating in the bloodstream(circulating tumor cells,CTCs)is considered to be a potential alternation to detect,characterize,and monitor cancer.Current methods for isolating CTCs are limited to complex analytic approaches that generate very low yield and purity.Here,we propose a high throughput 3D structured microfluidic chip integrated with surface plasmon resonance(SPR)sensor to isolate and identify CTCs from peripheral whole blood sample.The microfluidic velocity-field within the channel of the chip is mediated by an array of microposts protruding from upper surface of the channel.The height of microposts is shorter than that of the channel,forming a gap between the microposts and the lower surface of the channel.The lower surface of the channel also acts as the SPR sensor which can be used to identify isolated CTCs.Microfluidic velocity-field under different parameters of the arrayed microposts is studied through numerical simulation based on finite element method.Measurement on one of such fabricated microchips is conducted by our established optical Doppler tomography technique benefiting from its noninvasive,noncontact,and high-resolution spatialresolved capabilities.Both simulation and measurement of the microfluidic velocity-field within the structured channel demonstrates that it is feasible to introduce fluidic mixing and causes perpendicular flow component to the lower surface of the channel by the 3D structured microposts.Such mixing and approaching capabilities are especially desirable for isolation and identification of CTCs at the coated SPR sensor.
基金This work was supported in part by RF Govern-mental contracts 11.519.11.2035,14.B37.21.0728,14.B37.21.056314.B37.21.0216 and grants:FiDiPro,TEKES Program(40111/11),Finland+1 种基金SCOPES EC,Uzb/Switz/RF,Swiss NSF,IZ74ZO_137423/1RF President's grant"Scientific Schools",1177.2012.2.,Russian Foundation for Basic Research Grant No.12-02-31204 mol-a and No.a-11-02-00560.
文摘In experiments on newbom rats with stress related intracrani al hemorhage(ICH)using Doppler optical coberence tomognaphy(DOCT)we have shown that latent stage of ICH(4 h after stress)is characterized by decrease of venous blood outflow and the loss of sensitivity of sagittal vein to vasoconstrictor ffect of adrenaline.The incidence of ICH(24 h after stress)was accompanied by progressi on of early pathological changes in cerebral venous blood flow(CVBF)and development of venous insufficiency.Taking into consideration of this fact,we suggest that the suppression of CVBF related to the severity to the deleterious effect of stress on the brain hemodynamics in newborn rats.These facts allow us to conclude that the venous insufficiency with the loss of vasoconstrictor response to adrenaline is an informative and sensitive component of pattern of CVBF that can be important diagnostic criteria of risk of ICH development in newborns.
