Photodynamic therapy(PDT)is a minimally invasive method for treating oral leukoplakia In this paper,we propose a portable PDT device consisting of a flexible circuit board with a liquid flow cooling module on the back...Photodynamic therapy(PDT)is a minimally invasive method for treating oral leukoplakia In this paper,we propose a portable PDT device consisting of a flexible circuit board with a liquid flow cooling module on the back.The light source size was 17 mm×11 mm×4 mm,and the iradiation area of the light source was up to 100mm'.The iradiance range of this device was from 10mW/cm^(2)to 100mW/cm^(2).Simulation and experimental results showed that the irradiance cofficient variation for a treatment area of 81 mm was less than 7%.At an irradiance of 100 mW/cm a device surface temperature of lower than 42℃ can be achieved to satisfy the safety requirements under the con-ditions that the temperature of cooling liquid is 10℃ and the liquid flow speed is above 12 mL/min.展开更多
Traditionally,optical microscopy is used to visualize the morphological features of pathogenic bacteria,of which the features are further used for the detection and ident ification of the bacteria.However,due to the r...Traditionally,optical microscopy is used to visualize the morphological features of pathogenic bacteria,of which the features are further used for the detection and ident ification of the bacteria.However,due to the resolution limitation of conventional optical microscopy as well as the lack of standard pattern library for bacteria identification,the ffectiveness of this optical microscopy-based method is limited.Here,we reported a pilot study on a combined use of Structured Illumination Microscopy(SIM)with machine learning for rapid bacteria identification.After applying machine learning to the SIM image datasets from three model bacteria(including Escherichia coli,Mycobacterium smegmatis,and Pseudomonas aeruginosa),we obtained a classifcation accuracy of up to 98%.This study points out a promising possibility for rapid bacterial identification by morphological features.展开更多
Optical microscopy promises researchers to soe most tiny substances directly.However,the resolution of conventional microscopy is resticted by the diffraction limit.This makes it a challenge to observe subcellular pro...Optical microscopy promises researchers to soe most tiny substances directly.However,the resolution of conventional microscopy is resticted by the diffraction limit.This makes it a challenge to observe subcellular processes happened in nanoscale.The development of super-resolution microscopy provides a solution to this challenge.Here,we briefly review several commonly used super-resolution techniques,explicating their basic principles and applications in biological science,especially in neuroscience.In addition,characteristics and limitations of each techrique are compared to provide a guidance for biologists to choose the most suitable tool.展开更多
The oxygen adsorption can drastically alter the electronic properties of the two-dimensional(2D)materials,which is usually dificult to be removed.In this work,we report the ultraviolet(UV)ilumination induced desorptio...The oxygen adsorption can drastically alter the electronic properties of the two-dimensional(2D)materials,which is usually dificult to be removed.In this work,we report the ultraviolet(UV)ilumination induced desorption of the O2 molecules from the monolayer MoS2 surface by using the atmosphere dependent transport measurement,Kelvin probe microscopy,photoluminescence spectroscopy and X-ray photoelectron spectroscopy.Obvious increasing of the conductivity,rising of the Fermi level,and red shift of the photoluminescence peaks of the MoS2 were observed after the UV ilumination in vacuum,indicating the elimination of the depletion effect from the oxygen adsorption.Such parameter changes can be reversibly recovered by the subsequent O2 exposure.Furthermore,obvious decreasing of the oxygen concentration after the UV ilumination was also observed by X-ray photoelectron spectroscopy.Thus the UV induced O2 photodesorption effect is evidenced.The photo-excited charge transfer mechanism is proposed to account for the photodesorption effect.These results provide a nondestructive way to clean the MoS2 surface and manipulate the performance of the MoS2 based devices.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.81773349)the Program for New Clinical Techniques and Therapies of Peking University School and Hospital of Stomatology(Grant No.PKUSSNCT-21A13).
文摘Photodynamic therapy(PDT)is a minimally invasive method for treating oral leukoplakia In this paper,we propose a portable PDT device consisting of a flexible circuit board with a liquid flow cooling module on the back.The light source size was 17 mm×11 mm×4 mm,and the iradiation area of the light source was up to 100mm'.The iradiance range of this device was from 10mW/cm^(2)to 100mW/cm^(2).Simulation and experimental results showed that the irradiance cofficient variation for a treatment area of 81 mm was less than 7%.At an irradiance of 100 mW/cm a device surface temperature of lower than 42℃ can be achieved to satisfy the safety requirements under the con-ditions that the temperature of cooling liquid is 10℃ and the liquid flow speed is above 12 mL/min.
基金supported by the National Key Research and Development Program of China(Grant No.2017-YFD0500303)the National Natural Science Foundation of China(Grant Nos.31371106,91640105)+1 种基金the China Agriculture Research System(No.CARS-36)the Huazhong Agricultural University Scienti¯c and Technological Self-innovation Foundation(Program No.52204-13002).
文摘Traditionally,optical microscopy is used to visualize the morphological features of pathogenic bacteria,of which the features are further used for the detection and ident ification of the bacteria.However,due to the resolution limitation of conventional optical microscopy as well as the lack of standard pattern library for bacteria identification,the ffectiveness of this optical microscopy-based method is limited.Here,we reported a pilot study on a combined use of Structured Illumination Microscopy(SIM)with machine learning for rapid bacteria identification.After applying machine learning to the SIM image datasets from three model bacteria(including Escherichia coli,Mycobacterium smegmatis,and Pseudomonas aeruginosa),we obtained a classifcation accuracy of up to 98%.This study points out a promising possibility for rapid bacterial identification by morphological features.
基金support from National Basic Research Program of China (973 Program) (2015CB352005)National Natural Science Foundation of China (No.6142780065,31571110,81527901)+1 种基金Natural Science Foundation of Zhejiang Province of China (No.Y16F050002)the Fundamental Research Funds for the Central Universities.
文摘Optical microscopy promises researchers to soe most tiny substances directly.However,the resolution of conventional microscopy is resticted by the diffraction limit.This makes it a challenge to observe subcellular processes happened in nanoscale.The development of super-resolution microscopy provides a solution to this challenge.Here,we briefly review several commonly used super-resolution techniques,explicating their basic principles and applications in biological science,especially in neuroscience.In addition,characteristics and limitations of each techrique are compared to provide a guidance for biologists to choose the most suitable tool.
基金This work is supported by the National Natural Science Foundation of China(Nos.11074142 and 11021464)Collaborative Innovation Center of Weak Signal-Detecting Materials and Devices Integration of Anhui University(No.01001795-201601)+1 种基金Fundam ental Research Funds for the Central Universities(No.FRP-TP-18-076A1)the China Postdoctoral Science Foundation(No.2017M610857).
文摘The oxygen adsorption can drastically alter the electronic properties of the two-dimensional(2D)materials,which is usually dificult to be removed.In this work,we report the ultraviolet(UV)ilumination induced desorption of the O2 molecules from the monolayer MoS2 surface by using the atmosphere dependent transport measurement,Kelvin probe microscopy,photoluminescence spectroscopy and X-ray photoelectron spectroscopy.Obvious increasing of the conductivity,rising of the Fermi level,and red shift of the photoluminescence peaks of the MoS2 were observed after the UV ilumination in vacuum,indicating the elimination of the depletion effect from the oxygen adsorption.Such parameter changes can be reversibly recovered by the subsequent O2 exposure.Furthermore,obvious decreasing of the oxygen concentration after the UV ilumination was also observed by X-ray photoelectron spectroscopy.Thus the UV induced O2 photodesorption effect is evidenced.The photo-excited charge transfer mechanism is proposed to account for the photodesorption effect.These results provide a nondestructive way to clean the MoS2 surface and manipulate the performance of the MoS2 based devices.
