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Optically noninvasive measurement of the light transport properties of human meridians

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chinese Optics Letters 2008年第12期6卷 928-931页

作者：谢树森杨洪钦郭周义李晖刘颂豪 key laboratory of Optoelectronic science and Technology for medicine of Ministry of Education Fujian Provincial key laboratory of photonic Technology Institute of Laser and Optoelectronics TechnologyFujian Normal University laboratory of photonic Traditional chinese medicine and key laboratory of laser life science of Ministry of Education South China Normal University

To confirm the existence and properties of human meridians, the optical transport properties along the pericardium meridian and tissues around the pericardium meridian are studied noninvasively on twenty healthy volunteers in vivo and then compared with each other. Our study shows that the light propagating along the meridian and non-meridian directions both conform to the Beer＇s exponential attenuation law. However, statistical analysis of the results suggests that the optical transport properties of human meridian differ from those of the surrounding tissues over a low modulated frequency range （P 〈 0.01）, and light attenuation along the pericardium meridian is significantly less than that along the non-meridian direction. These findings not only indicate the existence of acupuncture meridian from the point of view of biomedical optics, but also shed new light on an approach to investigation of human meridians.

关键词： Beverages Histology Light

photonic band structures of quadrangular multiconnected networks

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chinese Physics B 2010年第7期19卷 313-321页

作者：宋欢欢杨湘波 moe key laboratory of laser life science & Institute of laser life science South China Normal University

By means of the network equation and generalized dimensionless Floquet-Bloch theorem, this paper investigates the properties of the band number and width for quadrangular multiconnected networks （QMNs） with a different number of connected waveguide segments （NCWSs） and various matching ratio of waveguide length （MRWL）. It is found that all photonic bands are wide bands when the MRWL is integer. If the integer attribute of MRWL is broken, narrow bands will be created from the wide band near the centre of band structure. For two-segment-connected networks and three-segment-connected networks, it obtains a series of formulae of the band number and width. On the other hand, it proposes a so-called concept of two-segment-connected quantum subsystem and uses it to discuss the complexity of the band structures of QMNs. Based on these formulae, one can dominate the number, width and position of photonic bands within designed frequencies by adjusting the NCWS and MRWL. There would be potential applications for designing optical switches, optical narrow-band filters, dense wavelength-division-multiplexing devices and other correlative waveguide network devices.

关键词： multiconnected network waveguide photonic band structure

Band rules for the frequency spectra of three kinds of aperiodic photonic crystals with negative refractive index materials

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chinese Physics B 2009年第12期18卷 5313-5325页

作者：全小林杨湘波 moe key laboratory of laser life science & Institute of laser life science South China Normal University

By means of the theory of electromagnetic wave propagation and transfer matrix method, this paper investigates the band rules for the frequency spectra of three kinds of one-dimensional （1D） aperiodic photonic crystals （PCs）, generalized Fibonacci GF（p, 1）, GF（1,2）, and Thue Morse （TM） PCs, with negative refractive index （NRI） materials. It is found that all of these PCs can open a broad zero-n gap, TM PC possesses the largest zero-n gap, and with the increase of p, the width of the zero-n gap for GF（p, 1） PC becomes smaller. This characteristic is caused by the symmetry of the system and the open position of the zero-n gap. It is found that for GF（p, 1） PCs, the possible limit zero-n gaps open at lower frequencies with the increase of p, but for GF（1,2） and TM PCs, their limit zero-n gaps open at the same frequency. Additionally, for the tbree bottom-bands, we find the interesting perfect self-similarities of the evolution structures with the increase of generation, and obtain the corresponding subband-number formulae. Based on 11 types of evolving manners Qi （i = 1, 2,... , 11） one can plot out the detailed evolution structures of the three kinds of aperiodic PCs for any generation.

关键词： negative refractive index photonic crystals generalized Fibonacci photonic crystal Thue-Morse photonic crystal

Optical transmission through basic-structural-unit superlattices

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chinese Physics B 2010年第9期19卷 627-633页

作者：张国刚杨湘波 moe key laboratory of laser life science & Institute of laser life science South China Normal University

In this paper, by the transparent-component-decimation （TCD） method we obtain three kinds of new basic- components （BCs） through simplifying and decomposing the BCs of three-component Thue-Morse （3CTM） sequence. Based on these new BCs we propose a type of basic-structural-units （BSUs） and investigate the optical transmission of the one-dimensional （1D） superlattices composed of these BSUs. It is found that if the substrates of the 1D BSU superlattices are certain, the optical transmission at the central wavelength （CW） will be determined completely by the number and the type of BSUs and has nothing to do with the marshalling sequence. In particular, if the substrates are identical, the numbers of different types of BSUs are all the same and the middle two elements of BSUs constitute a cycle, then no matter whether the system is periodic, or quasiperiodic, or aperiodic, or unordered, or even random, it will be transparent at the CW. The conclusion is confirmed by the numerical results. Similar to the even layers of neighbourhood identical elements in TCD method, such a kind of optical BSU subsystem can also be decimated from the chain in the process of transmission investigation. There would be a potential application in the designing of some interesting optical devices.

关键词： optical transmission basic-structural-units superlattices

Influence of Deviation on Optical Transmission through Aperiodic Superlattices

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chinese Physics Letters 2007年第11期24卷 3129-3132页

作者：殷海龙杨湘波兰胜胡巍 moe key laboratory of laser life science and Institute of laser life science South China Normal University Guangzhou 510631 laboratory of photonic Information Technology South China Normal University Guangzhou 510631

We propose a deviation model and study the influences of the relative error and sensitivity of a machine on the transmission coefficients （TCs） of Fibonacci superlattices. It is found that for a system with fewer layers, the influence of deviation can be ignored. When superlattices become more complicated, they may be fabricated by a machine with suitable relative error and possess the designed value of TO. However, when the number of system layers exceeds some critical value, superlattices should be manufactured only by precise machines. The influence of the sensitivity is also discussed.

关键词： coated conductor buffer layer self-epitaxy CeO2

Fast Microwave-Induced Thermoacoustic Tomography Based on Multi-Element Phase-Controlled Focus Technique

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chinese Physics Letters 2006年第5期23卷 1215-1218页

作者：曾吕明邢达谷怀民杨迪武杨思华向良忠 moe key laboratory of laser life science and Institute of laser life science South China Normal University Guangzhou 510631

We develop a fast microwave-induced thermoacoustic tomography system based on a 320-element phase-controlled focus linear transducer array. A 1.2-GHz microwave generator transmits microwave with a pulse width of 0.5 μs and an incident energy density of 0. 45 mJ/cm^2, and the microwave energy is delivered by a rectangular waveguide with a cross section of （80.01 ± 0.02） × 10^-4 m^2. Compared to single transducer collection, the system with the multi-element linear transducer array can eliminate the mechanical rotation of the transducer, hence can effectively reduce the image blurring and improve the image resolution. Using a phase-controlled focus technique to collect thermoacoustic signals, the data need not be averaged because of a high signal-to-noise ratio, resulting in a total data acquisition time of less than 5 s. The system thus provides a rapid and reliable approach to thermoacoustic imaging, which can potentially be developed as a powerful diagnostic tool for early-stage breast caners.

关键词： LINEAR TRANSDUCER ARRAY BIOLOGICAL TISSUES SYSTEM WAVES ALGORITHM

In Vivo Monitoring of Neovascularization in Tumour Angiogenesis by Photoacoustic Tomography

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chinese Physics Letters 2007年第3期24卷 751-754页

作者：向良忠邢达谷怀民周非凡杨迪武曾吕明杨思华 moe key laboratory of laser life science and Institute of laser life science South China Normal University Guangzhou 510631

Photoacoustic tomography （PAT） is presented to in vivo monitor neovascularization in tumour angiogenesis with high resolution and high contrast images in a rat. With a circular scan system, the photoacoustic signal, generated by laser pulses at a wavelength of 532nm from a Q-switched Nd：YAG laser is captured by a hydrophone with a diameter of 1 mm and a sensitivity of 850nV/Pa. The vascular structure around the rat tumour is imaged clearly, with optimal contrast, because blood has strong absorption near this wavelength. Serial noninvasive photoacoustic images of neovascularization in tumour angiogenesis are also obtained consecutively from a growing tumour implanted under the skin of a rat over a period of two weeks. This work demonstrates that PAT can potentially provide a powerful tool for tumour angiogenesis detection in cancer research. It will bring us closer to clinical applications for tumour diagnosis and treatment monitoring.

关键词： ONCOLOGY

Second-harmonic generation as a DNA malignancy indicator of prostate glandular epithelial cells

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chinese Physics B 2010年第4期19卷 492-496页

作者：庄正飞刘汉平郭周义卓双木喻碧英邓小元 moe key laboratory of laser life science South China Normal University key laboratory of Optoelectronic science and Technology for medicine Ministry of EducationFujian Normal University

This paper first demonstrates second-harmonic generation （SHG） in the intact cell nucleus, which acts as an optical indicator of DNA malignancy in prostate glandular epithelial cells. Within a scanning region of 2.7 μm×2.7μm in cell nuclei, SHG signals produced from benign prostatic hyperplasia （BPH） and prostate carcinoma （PC） tissues （mouse model C57BL/6） have been investigated. Statistical analyses （t test） of a total of 405 measurements （204 nuclei from BPH and 201 nuclei from PC） show that SHG signals from BPH and PC have a distinct difference （p 〈 0.05）, suggesting a potential optical method of revealing very early malignancy in prostate glandular epithelial cells based upon induced biochemical and/or biophysical modifications in DNA.

关键词： nonlinear microscopy multiharmonic generation diagnostic applications of nonlinear optics

How Many Methanol Molecules Can Solvate a Glycine: a PBE1PBE Approach

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chinese Journal of Structural Chemistry 2011年第11期30卷 1656-1671页

作者：王红磊邹昊胡勇军 moe key laboratory of laser life science & Institute of laser life science College of Biophotonics South China Normal University

Microsolvation of glycine in methanol clusters is explored by the use of DFT calculation method. The lowest energy conformations within 16.72 kJ·mol^-1 of the glycine clustering with one to six methanol molecules, which are obtained at the B3LYP/6-31＋G（d） level of theory, are reoptimized at PBE1PBE/6-311＋G（d,p）. The calculated results agree with our previous results with B3LYP （Chin. J. Chem. Phys. 22 （2009） 577） that the clusters of two forms （Z- and N-form） tend to be isoenergetic when the number of the solvate molecules reaches six. Furthermore, this result is in good agreement with the experiment of the tryptophan-methanol clusters, implying that the present treatments are reasonable and reliable. The results also indicate that nine methanol molecules are not enough to fully solvate a glycine molecule, and a tentative estimation is obtained that ten methanol molecules may fully solvate a glycine molecule, which consists with the experiment results.

关键词： DFT microsolvation gibbs free energy amino acid glycine