Background:Alzheimer's disease(AD)is a progressive neurodegenerative disease with no effective therapies.It is well known that chronic neuroinflammation plays a critical role in the onset and progression of AD.Wel...Background:Alzheimer's disease(AD)is a progressive neurodegenerative disease with no effective therapies.It is well known that chronic neuroinflammation plays a critical role in the onset and progression of AD.Well-balanced neuronal-microglial interactions are essential for brain functions.However,determining the role of microglia—the primary immune cells in the brain—in neuroinflammation in AD and the associated molecular basis has been challenging.Methods:Inflammatory factors in the sera of AD patients were detected and their association with microglia activation was analyzed.The mechanism for microglial inflammation was investigated.IL6 and TNF-α were found to be significantly increased in the AD stage.Results:Our analysis revealed that microglia were extensively activated in AD cerebra,releasing sufficient amounts of cytokines to impair the neural stem cells(NSCs)function.Moreover,the ApoD-induced NLRC4 inflammasome was activated in microglia,which gave rise to the proinflammatory phenotype.Targeting the microglial ApoD promoted NSC self-renewal and inhibited neuron apoptosis.These findings demonstrate the critical role of ApoD in microglial inflammasome activation,and for the first time reveal that microglia-induced inflammation suppresses neuronal proliferation.Conclusion:Our studies establish the cellular basis for microglia activation in AD progression and shed light on cellular interactions important for AD treatment.展开更多
在采用高阶滤波器的三电平变流器中,载波同相层叠调制(phase disposition,PD)产生的开关频率次边带谐波易扩散到高阶滤波器固有谐振点附近,引起输出电流谐波增加或振荡,而载波交替反相层叠(alternative phase opposition disposition,AP...在采用高阶滤波器的三电平变流器中,载波同相层叠调制(phase disposition,PD)产生的开关频率次边带谐波易扩散到高阶滤波器固有谐振点附近,引起输出电流谐波增加或振荡,而载波交替反相层叠(alternative phase opposition disposition,APOD)所需滤波器总电感量较大。针对以上问题,在定量分析比较PD和APOD两种调制方式谐波分布及边带谐波扩散特点的基础上,给出了两种调制方式总电感量约束方程。为保有APOD调制谐波分布集中优点的同时减小APOD总电感量需求,研究了一种基于最优三次谐波注入的改进APOD调制策略,分析了不同三次谐波注入量对APOD电压谐波分布及总电感量需求的影响,进而给出了以总电感量需求最小为目标的三次谐波最优注入量的计算方法,该方法可以实时根据当前调制度自动计算需要注入的三次谐波最优幅值,实现最优三次谐波的在线注入。最后,仿真和实验结果表明,所提策略不仅可以有效地避开高阶滤波器的谐振点,而且可有效降低主导谐波电压幅值,从而减小所需滤波器总电感量。展开更多
A double-exposure fabrication method without any intensity shadow mask to fabricate arbitrarily apodized fiber Bragg gratings（ FBGs） with narrow bandwidth is demonstrated by controlling the total ultra violet （UV）...A double-exposure fabrication method without any intensity shadow mask to fabricate arbitrarily apodized fiber Bragg gratings（ FBGs） with narrow bandwidth is demonstrated by controlling the total ultra violet （UV） irradiation along the grating by varying the speed of a translation stage. The UV source used is a stable continuous intracavity frequency-doubled argonion laser. The parameters （such as length, apodization profile, average index change）of FBGs can be easily changed with this method. The total UV irradiation is kept constant in the doubleexposure process because of the precise control of the exposure time, which ensures that the apodized FBG＇s bandwidth can be extremely narrow. The full width at half maximum （FWHM） bandwidth of the 2-cm-long apodized FBG fabricated by this method is 0. 15 nm with a maximum reflectivity of more than 95%.展开更多
Sensors play an important role in shaping and monitoring human health.Exploration of methods to use Fiber Bragg Grating(FBG)with enhanced sensitivity has attracted great interest in the field of medical research.In th...Sensors play an important role in shaping and monitoring human health.Exploration of methods to use Fiber Bragg Grating(FBG)with enhanced sensitivity has attracted great interest in the field of medical research.In this paper,a novel apodization function is proposed and performance evaluation and optimization of the same have been made.A comparison was conducted between various existing apodization functions and the proposed one based on optical characteristics and sensor parameters.The results evince the implementation of the proposed apodization function for vital sign measurement.The optical characteristics considered for evaluation are Peak Resonance Reflectivity level,Side Lobes Reflectivity level and FullWidth HalfMaximum(FWHM).The proposed novel apodization novel function has better FWHM,which is narrower than the FWHM of uniform FBG.Sensor characteristics like a quality parameter,detection accuracy and sensitivity also show improvement.The proposed novel apodization function is demonstrated to have a better shift in wavelength in terms of temperature and pulse measurement than the existing functions.The sensitivity of the proposed apodized function is enhanced with a Poly-dimethylsiloxane coating of varying thickness,which is 6 times and 5.14 times greater than uniform Fiber Bragg grating and FBG with the proposed novel apodization function,respectively,enhancing its utilization in the field of medicine.展开更多
Sparrow criterion of resolution is used for assessment of the resolution of two object points of apodized optical systems under incoherent illumination of light. Semicircular arrays of circular aperture with discrete ...Sparrow criterion of resolution is used for assessment of the resolution of two object points of apodized optical systems under incoherent illumination of light. Semicircular arrays of circular aperture with discrete asymmetric apodization have suppressed side-lobes and a narrower central peak in the image plane termed as PSF good side on alternatively the right and left of the strong spectral point facilitates to detect the presence of weak spectral point in the vicinity of bright spectral point. The results of investigations on optimum discrete pupil function with semicircular arrays on the intensity distributions in the composite image of two object points with widely varying in their intensities under various degree of coherence of illumination have been studied. Sparrow resolution limits and the dip in central intensity as function of degree of coherence of the illumination (γ), intensity ratio (α), degree of asymmetric apodization (b) and number of discrete elements in semicircular array (n). The efficiency of aperture functions is discussed in terms of these parameters. Pupil function capabilities in redistribution of energy in composite image of two object points in close vicinity have been verified for different considerations. Current study has found an improvement in two-point resolution characteristics compared to their unapodized counter part. Fourier analytical properties of an optical system are presented for evaluation of this practical problem.展开更多
This paper numerically and analytically investigates the formation and propagation motion of optical soliton in the Bragg grating. We choose the fibre Bragg grating with hyperbolic tangent apodization in the middle se...This paper numerically and analytically investigates the formation and propagation motion of optical soliton in the Bragg grating. We choose the fibre Bragg grating with hyperbolic tangent apodization in the middle section in order to obtain slower solitons. Optical fibre soliton but not Bragg grating soliton is used as input pulse in the discussion, which is much more approximate to the light source for the practical purpose. We discuss in detail the effects of the soliton＇s velocity with some parameters in the process of transmission. The results show that by choosing special parameters, one can make the soliton slow-down with a little distortion and energy decay and obtain tunable time-delay on a small scale.展开更多
The point spread function(PSF)caused by a wavefront coding system with a cubic phase mask has big side-lobes which leads to bad image restoration.This paper proposes a novel apodized cubic phase mask to suppress the s...The point spread function(PSF)caused by a wavefront coding system with a cubic phase mask has big side-lobes which leads to bad image restoration.This paper proposes a novel apodized cubic phase mask to suppress the side-lobes of the PSF.Simulated annealing algorithm is used to optimize the cubic and the truncation parameter of the phase mask.The system with the novel phase mask has better performance in the modulation transfer function(MTF)especially in low-and-medium spatial frequency region.The simulation results show that the restored images with the novel phase mask are superior to the one with the classic cubic phase mask in contrast and ringing effect.The experimental results show that the side-lobes of the PSF are suppressed by using the apodized cubic phase mask.展开更多
Background:Breast cancer is the most common cancer,and abnormal lipid metabolism is associated with cancer.APOD expression is negatively correlated with various cancers related to tumor prognosis.DNA methylation may a...Background:Breast cancer is the most common cancer,and abnormal lipid metabolism is associated with cancer.APOD expression is negatively correlated with various cancers related to tumor prognosis.DNA methylation may affect APOD expression.Therefore,this paper aims to investigate the significance of APOD expression and APOD DNA methylation in breast cancer.Methods:This study utilized comprehensive bioinformatics analysis of APOD using Gene Expression database of Normal and Tumor tissues 2,UCSC Xena,etc.Clinical and survival information obtained from the The Cancer Genome Atlas and Gene Expression Omnibus datasets were extracted for data mining.Results:The correlation between APOD and breast cancer was examined,along with the connection between APOD DNA methylation and APOD expression.In the The Cancer Genome Atlas cohort,as well as GSE31448 and GSE65194 datasets,APOD expression decreased in breast cancer(P<0.0001).Clinical feature analysis results showed that APOD expression was correlated with the PAM50 subtype,with the lowest expression in the Basal subtype(P<0.0001).High APOD expression is a good prognostic marker for breast cancer(HR=0.71,P=0.037).APOD methylation level was significantly negatively correlated with expression level(R=−0.4770,P<0.001),and cg15231202,cg23720929,and cg05624196 were important regulatory targets.High APOD expression was associated with higher metabolism and extracellular matrix scores.Conclusion:APOD is an independent prognostic marker for breast cancer and is regulated by DNA methylation to modulate mRNA expression.展开更多
The coherence factor of a single parameter is difficult to simultaneously improve the resolution and contrast of ultrasound images in complex imaging scenarios.Therefore,an ultrasound imaging algorithm combining optim...The coherence factor of a single parameter is difficult to simultaneously improve the resolution and contrast of ultrasound images in complex imaging scenarios.Therefore,an ultrasound imaging algorithm combining optimal apodization function and multi-parameter composite conditional factor(OA-MCCF)is proposed to improve the overall image quality.Firstly,several sets of apodization window functions are weighted on the received echo signals,and the optimal apodization function is selected based on the principle of minimizing the variance of the beamformer output.Secondly,the selected apodization function is weighted onto the echo signals to obtain the optimized array signals,and the current conditional coherence is calculated by the signals at multiple sampling times.Finally,the weighted factor is obtained by composing the conditional factors with multiple parameters according to the global image coherence information.The simulated and experimental results demonstrate that,compared with the traditional delay-and-sum algorithm,the proposed OA-MCCF algorithm can significantly enhance image resolution and contrast.Specifically,the OA-MCCF algorithm can achieve the greatest improvements in full width at half maximum of 89.23%in the point-target simulation and 63.22%in the carotid longitudinal-section experiment.Compared with the traditional coherence factor algorithm,the proposed algorithm improves resolution performance while maintaining image contrast.展开更多
基金supported by the Guiding Science and Technology Development Grant in the Social Sector of Luoyang(2101083A)。
文摘Background:Alzheimer's disease(AD)is a progressive neurodegenerative disease with no effective therapies.It is well known that chronic neuroinflammation plays a critical role in the onset and progression of AD.Well-balanced neuronal-microglial interactions are essential for brain functions.However,determining the role of microglia—the primary immune cells in the brain—in neuroinflammation in AD and the associated molecular basis has been challenging.Methods:Inflammatory factors in the sera of AD patients were detected and their association with microglia activation was analyzed.The mechanism for microglial inflammation was investigated.IL6 and TNF-α were found to be significantly increased in the AD stage.Results:Our analysis revealed that microglia were extensively activated in AD cerebra,releasing sufficient amounts of cytokines to impair the neural stem cells(NSCs)function.Moreover,the ApoD-induced NLRC4 inflammasome was activated in microglia,which gave rise to the proinflammatory phenotype.Targeting the microglial ApoD promoted NSC self-renewal and inhibited neuron apoptosis.These findings demonstrate the critical role of ApoD in microglial inflammasome activation,and for the first time reveal that microglia-induced inflammation suppresses neuronal proliferation.Conclusion:Our studies establish the cellular basis for microglia activation in AD progression and shed light on cellular interactions important for AD treatment.
文摘在采用高阶滤波器的三电平变流器中,载波同相层叠调制(phase disposition,PD)产生的开关频率次边带谐波易扩散到高阶滤波器固有谐振点附近,引起输出电流谐波增加或振荡,而载波交替反相层叠(alternative phase opposition disposition,APOD)所需滤波器总电感量较大。针对以上问题,在定量分析比较PD和APOD两种调制方式谐波分布及边带谐波扩散特点的基础上,给出了两种调制方式总电感量约束方程。为保有APOD调制谐波分布集中优点的同时减小APOD总电感量需求,研究了一种基于最优三次谐波注入的改进APOD调制策略,分析了不同三次谐波注入量对APOD电压谐波分布及总电感量需求的影响,进而给出了以总电感量需求最小为目标的三次谐波最优注入量的计算方法,该方法可以实时根据当前调制度自动计算需要注入的三次谐波最优幅值,实现最优三次谐波的在线注入。最后,仿真和实验结果表明,所提策略不仅可以有效地避开高阶滤波器的谐振点,而且可有效降低主导谐波电压幅值,从而减小所需滤波器总电感量。
基金The Natural Science Foundation of Jiangsu Province(No.BK2004207)
文摘A double-exposure fabrication method without any intensity shadow mask to fabricate arbitrarily apodized fiber Bragg gratings（ FBGs） with narrow bandwidth is demonstrated by controlling the total ultra violet （UV） irradiation along the grating by varying the speed of a translation stage. The UV source used is a stable continuous intracavity frequency-doubled argonion laser. The parameters （such as length, apodization profile, average index change）of FBGs can be easily changed with this method. The total UV irradiation is kept constant in the doubleexposure process because of the precise control of the exposure time, which ensures that the apodized FBG＇s bandwidth can be extremely narrow. The full width at half maximum （FWHM） bandwidth of the 2-cm-long apodized FBG fabricated by this method is 0. 15 nm with a maximum reflectivity of more than 95%.
基金supported in part by Universiti Malaya,and ACU UK under Project No.IF063-2021.
文摘Sensors play an important role in shaping and monitoring human health.Exploration of methods to use Fiber Bragg Grating(FBG)with enhanced sensitivity has attracted great interest in the field of medical research.In this paper,a novel apodization function is proposed and performance evaluation and optimization of the same have been made.A comparison was conducted between various existing apodization functions and the proposed one based on optical characteristics and sensor parameters.The results evince the implementation of the proposed apodization function for vital sign measurement.The optical characteristics considered for evaluation are Peak Resonance Reflectivity level,Side Lobes Reflectivity level and FullWidth HalfMaximum(FWHM).The proposed novel apodization novel function has better FWHM,which is narrower than the FWHM of uniform FBG.Sensor characteristics like a quality parameter,detection accuracy and sensitivity also show improvement.The proposed novel apodization function is demonstrated to have a better shift in wavelength in terms of temperature and pulse measurement than the existing functions.The sensitivity of the proposed apodized function is enhanced with a Poly-dimethylsiloxane coating of varying thickness,which is 6 times and 5.14 times greater than uniform Fiber Bragg grating and FBG with the proposed novel apodization function,respectively,enhancing its utilization in the field of medicine.
文摘Sparrow criterion of resolution is used for assessment of the resolution of two object points of apodized optical systems under incoherent illumination of light. Semicircular arrays of circular aperture with discrete asymmetric apodization have suppressed side-lobes and a narrower central peak in the image plane termed as PSF good side on alternatively the right and left of the strong spectral point facilitates to detect the presence of weak spectral point in the vicinity of bright spectral point. The results of investigations on optimum discrete pupil function with semicircular arrays on the intensity distributions in the composite image of two object points with widely varying in their intensities under various degree of coherence of illumination have been studied. Sparrow resolution limits and the dip in central intensity as function of degree of coherence of the illumination (γ), intensity ratio (α), degree of asymmetric apodization (b) and number of discrete elements in semicircular array (n). The efficiency of aperture functions is discussed in terms of these parameters. Pupil function capabilities in redistribution of energy in composite image of two object points in close vicinity have been verified for different considerations. Current study has found an improvement in two-point resolution characteristics compared to their unapodized counter part. Fourier analytical properties of an optical system are presented for evaluation of this practical problem.
基金supported by the National Natural Science Foundation of China (Grant No. 60677003)
文摘This paper numerically and analytically investigates the formation and propagation motion of optical soliton in the Bragg grating. We choose the fibre Bragg grating with hyperbolic tangent apodization in the middle section in order to obtain slower solitons. Optical fibre soliton but not Bragg grating soliton is used as input pulse in the discussion, which is much more approximate to the light source for the practical purpose. We discuss in detail the effects of the soliton＇s velocity with some parameters in the process of transmission. The results show that by choosing special parameters, one can make the soliton slow-down with a little distortion and energy decay and obtain tunable time-delay on a small scale.
文摘The point spread function(PSF)caused by a wavefront coding system with a cubic phase mask has big side-lobes which leads to bad image restoration.This paper proposes a novel apodized cubic phase mask to suppress the side-lobes of the PSF.Simulated annealing algorithm is used to optimize the cubic and the truncation parameter of the phase mask.The system with the novel phase mask has better performance in the modulation transfer function(MTF)especially in low-and-medium spatial frequency region.The simulation results show that the restored images with the novel phase mask are superior to the one with the classic cubic phase mask in contrast and ringing effect.The experimental results show that the side-lobes of the PSF are suppressed by using the apodized cubic phase mask.
基金The study design,data collection,data analysis,manuscript preparation,and publication decisions of this work were supported by the Science and Technology Program of Zhejiang Province Traditional Chinese Medicine(2023ZL056,2023ZL409)the Foundation Project of Zhejiang Chinese Medical University(2022JKZKTS26,2022JKJNTZ16,2022JKJNTZ23).
文摘Background:Breast cancer is the most common cancer,and abnormal lipid metabolism is associated with cancer.APOD expression is negatively correlated with various cancers related to tumor prognosis.DNA methylation may affect APOD expression.Therefore,this paper aims to investigate the significance of APOD expression and APOD DNA methylation in breast cancer.Methods:This study utilized comprehensive bioinformatics analysis of APOD using Gene Expression database of Normal and Tumor tissues 2,UCSC Xena,etc.Clinical and survival information obtained from the The Cancer Genome Atlas and Gene Expression Omnibus datasets were extracted for data mining.Results:The correlation between APOD and breast cancer was examined,along with the connection between APOD DNA methylation and APOD expression.In the The Cancer Genome Atlas cohort,as well as GSE31448 and GSE65194 datasets,APOD expression decreased in breast cancer(P<0.0001).Clinical feature analysis results showed that APOD expression was correlated with the PAM50 subtype,with the lowest expression in the Basal subtype(P<0.0001).High APOD expression is a good prognostic marker for breast cancer(HR=0.71,P=0.037).APOD methylation level was significantly negatively correlated with expression level(R=−0.4770,P<0.001),and cg15231202,cg23720929,and cg05624196 were important regulatory targets.High APOD expression was associated with higher metabolism and extracellular matrix scores.Conclusion:APOD is an independent prognostic marker for breast cancer and is regulated by DNA methylation to modulate mRNA expression.
基金supported by the National Natural Science Foundation of China(62071074)the Chongqing Natural Science Foundation Project(CSTB2022NSCQ-MSX0298).
文摘The coherence factor of a single parameter is difficult to simultaneously improve the resolution and contrast of ultrasound images in complex imaging scenarios.Therefore,an ultrasound imaging algorithm combining optimal apodization function and multi-parameter composite conditional factor(OA-MCCF)is proposed to improve the overall image quality.Firstly,several sets of apodization window functions are weighted on the received echo signals,and the optimal apodization function is selected based on the principle of minimizing the variance of the beamformer output.Secondly,the selected apodization function is weighted onto the echo signals to obtain the optimized array signals,and the current conditional coherence is calculated by the signals at multiple sampling times.Finally,the weighted factor is obtained by composing the conditional factors with multiple parameters according to the global image coherence information.The simulated and experimental results demonstrate that,compared with the traditional delay-and-sum algorithm,the proposed OA-MCCF algorithm can significantly enhance image resolution and contrast.Specifically,the OA-MCCF algorithm can achieve the greatest improvements in full width at half maximum of 89.23%in the point-target simulation and 63.22%in the carotid longitudinal-section experiment.Compared with the traditional coherence factor algorithm,the proposed algorithm improves resolution performance while maintaining image contrast.
