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We propose a nonvolatile, reconfigurable, and narrowband mid-infrared bandpass filter based on surface lattice resonance in phase-change material Ge2Sb2Te5. The proposed filter is composed of a two-dimensional gold nanorod array embedded in a thick Ge2Sb2Te5 film. Results show that when Ge2Sb2Te5 transits from the amorphous state to the crystalline state, the narrowband reflection spectrum of the proposed filter is tuned from 3.197 &mu, m to 4.795 &mu, m, covering the majority of the mid-infrared regime, the peak reflectance decreases from 72.6% to 25.8%, and the corresponding quality factor decreases from 19.6 to 10.3. We show that the spectral tuning range can be adjusted by varying the incidence angle or the lattice period. By properly designing the gold nanorod sizes, we also show that the quality factor can be greatly increased to 70 at the cost of relatively smaller peak reflection efficiencies, and that the peak reflection efficiency can be further increased to 80% at the cost of relatively smaller quality factors. We expect that this work will advance the engineering of Ge2Sb2Te5-based nonvalatile tunable surface lattice resonances and will promote their applications especially in reconfigurable narrowband filters.

Here we report a tunable polarization-independent broadband absorber in the terahertz regime. The proposed structure consists of periodic all-dielectric array on a gold substrate, sandwiched by a monolayer graphene and an epsilon-near-zero layer. Simulation results show that the absorption that is independent from the incident polarization remains above 90% over a broadband spectral range from 1.6 THz to 4.1 THz, corresponding to a bandwidth of 2.5 THz and a relative bandwidth of 87.7%. By varying the graphenes Fermi energy from 0.2 eV to 0.5 eV, the absorption bandwidth can be turned from 1.5 THz to 2.5 THz. We expect this polarization- independent absorber with dynamically tunable bandwidth can be used a filters in applications such as terahertz detectors.

Xuejun Qiu,1 Xinru You,2 Xing Chen,2 Haolin Chen,1 Arvind Dhinakar,3 Songhao Liu,1 Zhouyi Guo,1 Jun Wu,2,4 Zhiming Liu1 1SATCM Third Grade Laboratory of Chinese Medicine and Photonics Technology, College of Biophotonics, South China Normal University, 2Guangdong Provincial Key Laboratory of Sensor Technology and Biomedical Instrument, School of Engineering, Sun Yat-Sen University, Guangzhou, Guangdong, People’s Republic of China; 3Faculty of Engineering, University of Waterloo, Waterloo, ON, Canada; 4Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Sun Yat-Sen University, Guangzhou, Guangdong, People’s Republic of China Abstract: The rapid development of near-infrared surface-enhanced Raman scattering (NIR SERS) imaging technology has attracted strong interest from scientists and clinicians due to its narrow spectral bandwidth, low background interference, and deep imaging depth. In this report, the graphene oxide (GO)-wrapped gold nanorods (GO@GNRs) were developed as a smart and robust nanoplatform for ultrafast NIR SERS bioimaging. The fabricated GO@GNRs could efficiently load various NIR probes, and the in vitro evaluation indicated that the nanoplatform could exhibit a higher NIR SERS activity in comparison with traditional gold nanostructures. The GOs were prepared by directly pyrolyzing citric acid for greater convenience, and GO@GNRs were fabricated via a facile synthesis strategy. Higher NIR SERS activity, facile synthesis method, excellent biocompatibility, and superb stability make the GO@GNRs/probe complex promising nanoprobes for NIR SERS-based bioimaging applications. Keywords: gold nanorods, graphene oxide, near-infrared bioimaging, surface-enhanced Raman scattering

We report the design an ultra-broadband highly reflective subwavelength grating that covers almost the entire visible region. Results show that high reflectivity above 90% covering 450–700 nm can be achieved, corresponding to Δλ/λ=43%. We also provide intuitive physical insights into the broadband high reflection performance of reflector. We expect that this ultra-thin, ultra-broadband and highly reflective all-dielectric reflector can find applications in hyperspectral imaging based on tunable etalon filters.

In this paper, a new type of educational robot is devised to invigorate the kid’s mathematics education by taking the printed arithmetic equation as input and showing the result in form of 7-segment display method. An open source, Robotic Operating System ROS is applied to Pioneer 3, a differential drive robot from Omron Corporation, to identify image input and perform specific object relocation tasks. For the image processing module, a Kinect-based segmentation and recognition method is adopted. For the robotic motion module, a series of robotic perception and localization algorithm with PID control is implemented.

We propose a novel configuration for nonvolatile and reconfigurable tuning of surface lattice resonances (SLRs) based on thin films of phase-change material Ge2Sb2Te5 (GST). The configuration is composed of gold nanorod array embedded in a thin GST film. Results show that, an extremely wide SLR wavelength tuning range reaching 1600 nm, large tuning figure of merit of 21, and high SLR quality factors of 47 and 17 can be achieved in the mid-infrared regime when GST transits from the amorphous state into the crystalline state. The effects of the GST layer thicknesses on the SLR tuning performance are discussed, and the performances of several modified configurations are compared. We expect this work will advance the engineering of SLR tuning based on phase-change materials and promote its applications especially in nanolasing and narrowband filtering.

A surface plasmon resonance sensor based on a U-shaped photonic crystal fiber with a rectangular lattice has been designed through finite element method. The U-shaped fiber exhibits not only stronger mechanical strength but also better sensor performance than our previous scheme. The upper detection limit extends to higher analyze refractive index, 1.384, for phase interrogation. We introduce a ratio to evaluate the impact of higher order plasmonic mode. For wavelength modulation scheme, the parameter to describe the performance of a sensor is chosen to be the figure of merit, which can be up to 533.8[RIU−1] around complete coupling condition.

We report the design of broadband highly reflective subwavelength high-index-contrast gratings (HCGs) for both TE and TM polarizations in the visible regime. Results show that high reflectivity above 99% covering 544–726 nm or 510–666 nm can be achieved, corresponding to a fractional bandwidth of Δλ/λ0 = 28.7% or 26.5% for the TM or TE polarization, respectively. We reveal that these broad high-reflectivity bands originate from a blend of multiple leaky modes, similar to the counterparts operating in the near-infrared regime. By investigating the effects of the grating height, period, and width, we find that the broadband high reflectivity requires careful optimization. We expect that this work will advance the engineering of broadband HCG reflectors and promote their applications in the visible regime.

In this paper, we provide some new logarithm and polynomial approximations, inequalities and rates of convergence of Glaisher–Kinkelin’s and Bendersky–Adamchik’s constants. To demonstrate the superiority of our new convergent sequences over the classical sequences and Mortici’s sequences, some numerical computations are also given at the end of this paper.

The chirality of photons plays a fundamental role in light-matter interactions. However, a limiting factor in photonic integrated circuits is the lack of a miniaturized component, which can distinguish the chirality in a low cost and integrated manner. Herein we numerically demonstrate a chirality-distinguishing beamsplitter that can address this challenge. It consists of an integrated polarization rotator and a linear polarization beamsplitter, which together can fulfill the task of distinguishing and splitting left- and right-handed quasi-circularly polarized modes on a chip with an ultra-broadband operation range from 1.45 μm to 1.65 μm. Owning to the reciprocity, the device can emit photons with selectable spin angular momentum depending on the chosen feeding waveguide. The device is compatible with complementary metal-oxide semiconductor technology and it may open up new avenues in the fields of on-chip nano-photonics, bio-photonics and quantum information science.

Gears are rotating machines, meshing with each other by teeth to transmit torque. Interestingly, the rotating directions of two meshing gears are opposite, clockwise and counterclockwise. Although this opposite handedness motion has been widely investigated in machinery science, the analogue behavior of light remains undiscovered. Here, we present a simple nanophotonic directional coupler structure which can generate two light beams with opposite handedness of polarization states-optical gears. Due to the abrupt phase shift effect and birefringence effect, the angular momentum (AM) states of photons vary with the propagation distance in two adjacent waveguides of the coupler. Thus, by the choice of coupling length, it is able to obtain two light beams with opposite handedness of polarization, confirming the appearance of optical gears. The full control in the handedness of output beams is achieved via tuning the relative phase between two orthogonal modes at the input port. Optical gears thus offer the possibility of exploring light-matter interactions in nanoscale, opening up new avenues in fields of integrated quantum computing and nanoscale bio-sensing of chiral molecules.

Data storage with ultrahigh density, ultralow energy, high security, and long lifetime is highly desirable in the 21st century and optical data storage is considered as the most promising way to meet the challenge of storing big data. Plasmonic coupling in regularly arranged metallic nanoparticles has demonstrated its superior properties in various applications due to the generation of hot spots. Here, the discovery of the polarization and spectrum sensitivity of random hot spots generated in a volume gold nanorod assembly is reported. It is demonstrated that the two-photon-induced absorption and two-photon-induced luminescence of the gold nanorods adjacent to such hot spots are enhanced significantly because of plasmonic coupling. The polarization, wavelength, and spatial multiplexing of the hot spots can be realized by using an ultralow energy of only a few picojoule per pulse, which is two orders of magnitude lower than the value in the state-of-the-art technology that utilizes isolated gold nanorods. The ultralow recording energy reduces the cross-talk between different recording channels and makes it possible to realize rewriting function, improving significantly both the quality and capacity of optical data storage. It is anticipated that the demonstrated technology can facilitate the development of multidimensional optical data storage for a greener future.

A novel full-duplex radio-over-fiber system is proposed and demonstrated, in which an external modulator and an optical interleaver are used to generate dual octupling-frequency optical millimeter waves for two base stations and wavelength reuse for uplink connection. This scheme is simplified and low-cost because no additional laser is utilized for uplink connection at two base stations and one laser at central office works for two base stations simultaneously. The frequency of local oscillator signal is reduced largely due to frequency octupling. The theorem about how to generate optical millimeter waves is analyzed. The simulation results show that the bidirectional 5 Gb/s system has a perfect performance because the power penalty for the downlink and uplink signals of two base stations are less than 0.6 dB after successful transmission over 60 km standard single mode fiber.

To explore the characteristics of light propagation along the Pericardium Meridian and its surrounding areas at human wrist by using optical experiment and Monte Carlo method.An experiment was carried out to obtain the distribution of diffuse light on Pericardium Meridian line and its surrounding areas at the wrist, and then a simplified model based on the anatomical structure was proposed to simulate the light transportation within the same area by using Monte Carlo method.The experimental results showed strong accordance with the Monte Carlo simulation that the light propagation along the Pericardium Meridian had an advantage over its surrounding areas at the wrist.The advantage of light transport along Pericardium Merdian line was related to components and structure of tissue, also the anatomical structure of the area that the Pericardium Meridian line runs.

Nanoscience is a grand and wide science, and there are many kinds of nanomaterials. In this paper nanomaterials are divided into three: the naturial nanocrystals, the artificial nano structural materials and the functional polymer materials. Carbon nanotechnologies which are in the fast-development areas are reviewed in detail including their structural features, opto-electronic properties and its applications used as optoelectronic devices. And the graphene are introduced in detail. Especially emphasize is put on the the carbon nanotechnology development and its importance.

Nanophotonic waveguides are the building blocks of integrated photonics. To date, while quarter-wave plates (QWPs) are widely used as common components for a wide range of applications in free space, there are almost no reports of Integratable QWPs being able to manipulate the angular momentum (AM) of photons inside nanophotonic waveguides. Here, we demonstrate two kinds of Integratable QWPs respectively based on the concept of abrupt phase change and birefringence effect. The orientation of the equivalent optical axis of an Integratable QWP is designable. Remarkably, a combination of two integratable QWPs with different equivalent optical axes leads to an integrated system that performances one-way AM conversion. Moreover, this system can be used as a point source that can excite different patterns on a metal surface via directional excitation of surface plasmon polaritons (SPP). These results allow for the control of AM of light in nanophotonic waveguides, which are crucial for various applications with limited physical space, such as on-chip bio-sensing and integrated quantum information processing.

Mid-Ultraviolet (UVB) has a significant influence on human health. In this study, human erythrocytes were exposed to UVB to investigate the effects of UVB radiation on erythrocytes membrane. And Micro-Raman spectroscopy was employed to detect the damage. Principal component analysis (PCA) was used to classify the control erythrocytes and the irradiated erythrocytes. Results showed that the erythrocytes membrane was damaged by Mid-Ultraviolet (UVB) radiation. The intensity of the Raman peaks at 1126 cm(-1) and 1082 cm(-1) were used to calculate the Longitudinal Order-Parameters in Chains (S(trans)) which can present the liquidity and ionic permeability of erythrocyte membrane. After UVB radiation for 30 min, both the liquidity and ionic permeability decreased. At the same time, the intensity of the peaks at 1302 cm(-1) (α-helix), 1254 cm(-1) (random coil), 1452 cm(-1) and 1430 cm(-1) (CH(2)/CH(3) stretch) have also changed which indicated the membrane protein also been damaged by UVB. In the whole process of radiation, the more UVB radiation dose the more damage on the erythrocyte membrane.

The aim was to test whether the typical NPC cell lines of 5-8F (high tumorigenesis and metastasis) and 6-10B (low tumorigenesis and metastasis) could be differentiated by polarization sensitive optical coherence tomography (PS-OCT). We imaged the two types of low cellular differentiated NPC cell lines 5-8F and 6-10B pellets using PS-OCT; then extracted the optical parameters of attenuate coefficient and anisotropy from the A-scan lines based on the multiple scattering model; and compared their phase retardation. The fitting scattering coefficients were μs=10.91±0.45 and μs=11.33±0.27 cm(-1) for 5-8F and 6-10B pellets (p

We have developed a mouse squamous cell carcinomas (SCC) model by diniethylbenzanthracene (DMBA) and ultraviolet (UVB). A silver colloid as SERS-active substrates is used for detecting the blood plasma of mouse. The relative intensity of the band at 942 and 1499 cm−1 is higher in SCC model than in healthy one. Therefore, it can be used as an important “fingerprint” in order to diagnose these diseases. Results show us how to get high signal-to-noise ratio of biological macromolecules surface-enhanced Raman scattering spectra in blood plasma. And also offer useful help for understanding the rich molecular structure information in biological tissues. It provides a molecular spectroscopy way for early detection of disease in blood plasma.

We tried to explore the intrinsic differences in the optical properties of the four representative NPC cell lines on the models of radiobiology and metastasis by OCT. The scattering coefficients and anisotropies were extracted by fitting the average a-scan attenuation curves based on the multiple scatter effect. The values of scattering coefficients and anisotropy factors were 5.21 ± 0.11, 5.30 ± 0.09, 5.92 ± 0.21, 6.97 ± 0.22, and 0.892 ± 0.009, 0.886 ± 0.006, 0.884 ± 0.009, 0.86 ± 0.01 for CNE1, CNE2, 5-8F and 6-10B pellets (p < 0.05, P = 0.07 for CNE1 and CNE2), respectively. The results showed that the radiobiology and metastasis cell's model could be distinguished obviously; which implied that the corresponding types of NPC tissue might be potentially differentiated by OCT. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Research on Mobile-Assisted Language Learning (MALL) has mostly focused on investigating the effectiveness and physical nature of mobile technology or the psychological conditions of learners. Studies of MALL that associate the fundamental principles of the human cognitive learning process is comparatively less common. Despite years of formal instruction, speaking a second language remains a challenge for beginner learners of Chinese as a Second Language (CSL) in Malaysian International Schools. To help explain this, a framework of Mobile-Assisted Second Language Learning (MASLL) is developed to explain the cross-channel mental representation process in acquiring the speaking skills of a second language, using mobile phones. A total of 30 middle-year school learners from Malaysian International Schools underwent a quantitative, quasi-experimental pilot study. Learners with only the auditory stimuli outscored learners with the auditory-visual stimuli, with a mean difference of 4.87 in the gain scores. Whilst recognising the importance of auditory-visual stimuli during the learning phase, these findings highlight the importance of activating cross-channel mental representation during the interface and acquisition phases. A larger sample is needed to further validate these findings. Future studies on neuroscience, which localise the brainwave analysis, will be useful in providing visual explanation of the human cognitive processes and memory coding in acquiring the speaking skills of a second language.

Objective To observe the clinical effects in the treatment of prostatic hyperplasia by laser radiation on acupoints.

The S parameter expression of high-frequency models of the high electron mobility transistors (HEMTs) with basic feedback structure, especially the transmission gain S21, is presented and analyzed. In addition, an improved feedback structure and its theory are proposed and demonstrated, in order to obtain a better gain-flatness through the mutual interaction between the series inductor and the parallel capacitor in the feedback loop. The optimization solution for the feedback amplifier can eliminate the negative impacts on transmission gain S21 caused by things such as resonance peaks. Furthermore, our theory covers the shortage of conventional feedback amplifiers, to some extent. A wideband low-noise amplifier (LNA) with the improved feedback technology is designed based on HEMT. The transmission gain is about 20 dB with the gain variation of 1.2 dB from 100 MHz to 6 GHz. The noise figure is lower than 2.8 dB in the whole band and the amplifier is unconditionally stable.

Detection efficiency is one of the key parameters that affect the performance of gated-mode avalanche photodiodes in quantum key distribution. In this paper, the impact of the waveform of faint picosecond laser pulses on detection efficiency is investigated both experimentally and analytically. Two kinds of laser pulses are attenuated to the single photon level to measure and plot single photon detection efficiency versus synchronous delay between the detector and the laser source. The results show that the narrower laser pulse with single peak can be detected with about 9% higher detection efficiency and lead to a lower QBER than the pulse with subpeak and a broadened pedestal.

To observe the influence of acupoint catgut-embedding therapy on the quality of life (QOL), the reproductive endocrine and bone metabolism of postmenopausal women.A total A total of 65 women with climacteric syndrome were enrolled and randomly assigned to two groups, thirty-three in the treatment group on whom acupoint catgut-embedding was performed with Shenshu (BL23), Sanyinjiao (SP6) and Guanyuan (CV4) as main acupoints, and thirty-two in the control group who were only medicated with Fufuchun Capsule (妇复春胶囊). The treatment course for both groups was 3 months. Before and after Before and after treatment, the clinical symptoms, the QOL score, serum follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E(2)), testosterone (T), osteocalcin (BGP), parathyroid hormone (PTH), calcitonin (CT) and alkaline phosphatase (AKP) were measured. In addition, another 28 women with childbearing potential and normal regular menstrual cycle were selected and the reproductive endocrine hormone were tested in the ovulatory period as controls.The levels of serum FSH and LH of postmenopausal women were higher, and serum E(2) and T were lower than those of normal women (P0.01). After treatment, the levels of serum E(2) In both groups and T in the treatment group were increased, while in the control group the serum E(2) increase was more significant than that in the treatment group (P0.05), and serum T showed no statistical difference. The levels of serum FSH, LH, BGP, CT, PTH and AKP were reduced significantly in both groups after treatment (P0.05). The QOL scores were Increased remarkably in both groups on physiological functioning, bodily pain, general health, vitality, and mental health after treatment (P0.05),but the improvement of bodily pain and mental health in the treatment group were better than those in the control group (P0.01). There was no significant difference in the therapeutic effect between the two groups after treatment (P0.05).Acupoint catgut-embedding showed an obvious effect on climacteric syndrome, and enhanced the QOL in postmenopausal women. The therapy could regulate the hypothalamic-pituitary-ovarian axis to raise the serum E(2) level which may be significant in preventing and curing the osteoporosis in postmenopausal women.

Here we examined the effect of human normal breast (NB) and breast cancer (BC) tissues in vitro after treatment with glycerol in conjunction with ultrasound (surgeonperformed, SP) by OCT for functional imaging to monitor. 60% glycerol (G) and SP was simultaneously applied for 5 min. Depth- and time-resolved profiles for OCT signal enhancement were presented. The results show that OCT imaging depth of breast tissues after treatment with 60% G in combined with SP more obviously improved than that after application of glycerol alone. The permeability coefficient of 60% glycerol in 60% G/NB, 60% G/BC, 60% G/SP/NB, and 60% G/SP/BC were (0.91±0.02)×10-5 cm/s, (3.22±0.09)×10-5 cm/s, (1.63±0.04)×10-5 cm/s, and (7.98±0.19)×10-5 cm/s, respectively. The permeability coefficient of glycerol in 60% G/SP/NB was 1.84-fold than that in 60% G/NB, but there was 2.54-fold on permeability coefficient comparing 60% G/SP/BC with that in 60% G/BC. The results from this study indicated that the permeability coefficient of glycerol not only in normal breast tissues, but also in breast cancer tissues after treatment with ultrasound is larger than that in tissues without ultrasound.

Optical coherence tomography (OCT) holds great promise as a routine research tool for analysis of identifying the boundaries between normal and diseased breast tissue in vitro and in vivo. However, despite the depth penetration afforded by this imaging modality, light attenuation in tissues imposes limitations. Here we studied the optical clearing effect of glycerol in human cancer and normal breast tissues with OCT for functional imaging to monitor. Depth- and time-resolved profiles for OCT signal enhancement were presented. The results show that the OCT imaging depth and imaging contrast of breast tissues have been improved after application of 60% glycerol in the 2-D OCT images. The OCT slope signals of breast tissues decreased as glycerol diffusion into tissues, therefore, the water and intercellular fluids were drawn out from tissues. Then the reverse process due to water was drawn back into the cells as a result of its affinity for water. The permeability coefficient of 60% glycerol was (3.14±0.07)×10-5 cm/s in breast cancer tissues, and (0.89±0.02)×10-5 cm/s in normal breast tissues, respectively. The permeability coefficient of glycerol in cancer tissues was 3.54-fold than that in normal tissues. These results demonstrate that the optical clearing of normal and cancer breast tissues are improved after application of glycerol.

This study aimed to investigate the effect of low-intensity pulsed laser (LIPL; 650 nm, 2 mW) irradiation on mRNA expression of receptor activator of NF-kappaB ligand (RANKL) and osteoprotegerin (OPG) in rat calvarial cells.Cultured cells were treated with LIPL irradiation of 1.14 J/cm(2) (group A) or 2.28 J/cm(2) (group B), and non-irradiated cells (group C) were used as controls. The changes in cell numbers, alkaline phosphatase (ALP) activity, RANKL, and OPG mRNA expression in the three study groups was determined using MTT, UV/VIS spectrophotometry, and RT-PCR analyses.The cell numbers in groups A and B increased significantly (7.52% and 8.80%, respectively), as did ALP activity (71.95% and 88.20%, respectively), compared with group C (p0.001). Meanwhile, RANKL and OPG mRNA expression in group A were 51.06% lower and 3.35 times higher, respectively, than those seen in the controls (p0.05), and the RANKL:OPG mRNA ratio in group A was 81.82% lower than that in group C (p0.005).LIPL irradiation may directly promote osteoblast proliferation and differentiation, and indirectly inhibit osteoclast differentiation, by downregulating the RANKL:OPG mRNA ratio in osteoblasts. Thus LIPL irradiation may play an important role in bone remodeling, and should be valuable for the treatment of bone diseases such as osteoporosis.

Photobiomodulation (PBM) is a modulation of laser irradiation or monochromatic light (LI) on biosystems, which stimulates or inhibits biological functions but does not result in irreducible damage. LI might be of low intensity LI (LIL) (about 10 mW/cm2), or moderate intensity LI (MIL) (102-103 mW/cm2). PBM of LIL or MIL (LPBM or MPBM) is studied from the homeostatic viewpoint in this paper. Homeostasis is rede.ned as the function-specific homeostasis (FSH), a negative-feedback response of a biosystem which maintains the function-specific conditions inside it. PBM is classified into two kinds, the FSH-specific PBM (fPBM) and developmental PBM (dPBM). For fPBM, there is no PBM of LI on the function in FSH, but there is PBM of LI on the function far from FSH. dPBM can disrupt FSH. It can be found that LPBM is an fPBM, and whether MPBM is fPBM or dPBM depends on MIL dose and cell sensitivity. Low level LI therapy is just clinical applications of fPBM, so that it is a cellular rehabilitation.

We demonstrate experimentally an intrinsically stable polarization coding and decoding system composed of optical-fiber Sagnac interferometers with integrated phase modulators for quantum key distribution. An interference visibility of 98.35% can be kept longtime during the experiment without any efforts of active compensation for coding all four desired polarization states.

Based on the constant coefficients of Ginzburg-Landau equation that considers the influence of the doped fiber retarded time on the evolution of self-similar pulse, the parabolic asymptotic self-similar solutions were obtained by the symmetry reduction algorithm. The parabolic asymptotic amplitude function, phase function, strict linear chirp function and the effective temporal pulse width of self-similar pulse are given in this paper. And these theoretical results are consistent with the numerical simulations.

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 (Pl0.01), 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.

Error reconciliation is a necessary step for quantum key distribution process. In this paper, the correction ability of error reconciliation procedure which is called Winnow protocol is analyzed and estimated, moreover, it gives some expressions about it. The experiment results proved the capability of Winnow protocol are excellent. It is also indicates that the smallest N has the most correction efficiency where from the communication times between the legitimate parties and the data remaining efficiency consideration.

The bandgap properties of 2D 8-fold symmetric photonic quasicrystals (PQCs) composed of a set of rods are numerically investigated for various fill factors, dielectric constants and propagation angles using the finite difference time domain (FDTD) method. Some interesting properties are found besides the known results: (i) the central frequency of the bandgap shifts to low frequency as r/a increases; (ii) an optimum fill factor to obtain the largest gap width exists, which decreases with increasing dielectric constant; (iii) compared with the behavior for a given fill factor, the variation of bandgap width for the optimum fill factor increases much more significantly with the dielectric constant. Selection guidelines for 8-fold symmetric PQC designs are provided for optimum fill factors and variation of the relative bandgap width at different dielectric constants.

This study aims to characterize and classify serum surface-enhanced Raman spectroscopy (SERS) spectra between bladder cancer patients and normal volunteers by genetic algorithms (GAs) combined with linear discriminate analysis (LDA). Two group serum SERS spectra excited with nanoparticles are collected from healthy volunteers (n = 36) and bladder cancer patients (n = 55). Six diagnostic Raman bands in the regions of 481–486, 682–687, 1018–1034, 1313–1323, 1450–1459 and 1582–1587 cm−1 related to proteins, nucleic acids and lipids are picked out with the GAs and LDA. By the diagnostic models built with the identified six Raman bands, the improved diagnostic sensitivity of 90.9% and specificity of 100% were acquired for classifying bladder cancer patients from normal serum SERS spectra. The results are superior to the sensitivity of 74.6% and specificity of 97.2% obtained with principal component analysis by the same serum SERS spectra dataset. Receiver operating characteristic (ROC) curves further confirmed the efficiency of diagnostic algorithm based on GA-LDA technique. This exploratory work demonstrates that the serum SERS associated with GA-LDA technique has enormous potential to characterize and non-invasively detect bladder cancer through peripheral blood.

Confocal micro-Raman spectroscopy was used to distinguish human xanthelasma skin (HXS) from the human normal skin (HNS). Results showed that intensive Raman peaks at 1,269, 1,336, 1,448, and 1,656 cm(-1) increased obviously. Both 1,269 and 1,656 cm(-1) peaks showed that the proteins in HXS were mostly in the anti-parallel ß sheet conformation. While the intensities of bands at 1,032, 1,087, 1,300, and 1,448 cm(-1) belonged to lipids were enhanced in HXS spectrum compared to those in HNS spectrum. There were main intercellular lipids alkyl chains with minor proteins contribution at 1,087 cm(-1) and phenylalanine at 1,032 cm(-1) . To quantitative analysis of the difference, the ratio of I852/I829 was calculated, which was 1:1.04 ± 0.04 and 1:1.11 ± 0.02 for HNS and HXS (p 0.01), respectively. The data indicated that some tyrosine residues, which form a hydrogen bond with H2 O prior to aggregation, were captured by strong hydrogen-bond acceptors in the aggregate. The decreased ratio of I852/I829 indicated more hydrophobic in HXS than HNS. Principal component analysis showed a one-to-one relationship between human xanthelasma skin and the corresponding Raman spectra. It could be given useful help for the diagnostication of xanthelasma.