We present a graphics processing unit (GPU) cluster-based Monte Carlo simulation of photon transport in multi-layered tissues. The cluster is composed of multiple computing nodes in a local area network where each node is a personal computer equipped with one or several GPU(s) for parallel computing. In this study, the MPI (Message Passing Interface), the OpenMP (Open Multi-Processing) and the CUDA (Compute Unified Device Architecture) technologies are employed to develop the program. It is demonstrated that this designing runs roughly N times faster than that using single GPU when the GPUs within the cluster are of the same type, where N is the total number of the GPUs within the cluster.

We developed a novel method for real-time monitoring of alteration of the local epithelium vessel/capillary and blood oxygenation spatial pattern in epithelium exploiting a compact fibre sensor system based on spatially and spectrally resolved diffuse reflectance. The method is based on collection of spatially resolved diffuse reflectance R（λ） by fiber sensors. The spatial resolution is provided as a dependence of R（λ） on a set of distances ρ between the source and detector (attenuation curve). It is expected that the new method can reasonably extract the minor spatial deviations of oxygenation and local blood volume fraction — parameters, directly related to the local vessel density and capillary spatial patterns in the epithelium. Light scattering in visible range is naturally taken into account in the proposed method.

The precise classification for the electroencephalogram (EEG) in different mental tasks in the research on brain-computer interface (BCI) is the key for the design and clinical application of the system. In this paper, a new combination classification algorithm is presented and tested using the EEG data of right and left motor imagery experiments. First, to eliminate the low frequency noise in the original EEGs, the signals were decomposed by empirical mode decomposition (EMD) and then the optimal kernel parameters for support vector machine (SVM) were determined, the energy features of the first three intrinsic mode functions (IMFs) of every signal were extracted and used as input vectors of the employed SVM. The output of the SVM will be classification result for different mental task EEG signals. The study shows that mean identification rate of the proposed algorithm is 95%, which is much better than the present traditional algorithms.

Nasopharyngeal carcinoma (NPC) is a prevalent cancer in some areas of southern Asia. To explore the potential of photodynamic therapy (PDT) for the treatment of NPC, a small molecule prodrug 5-aminolevulinic acid (ALA) and its methyl ester (MAL) mediated PDT was studied in vitro. The results showed that human NPC cells were sensitive to both ALA- and MAL-mediated PDT. However, ALA was more effective than MAL, possiblly due to a higher efficiency of ALA on producing endogenous protoporphyrin (PpIX) in NPC cells. Neither ALA nor MAL caused any significant genotoxicity. The ALA-based PDT might be a useful modality in the treatment ofNPC.

This paper presents a novel biosensor for bitter substance detection on the basis of light addressable potentiometric sensor (LAPS). Taste receptor cells (TRCs) were used as sensitive elements, which can respond to different bitter stimuli with extreme high sensitivity and speci- ficity. TRCs were isolated from the taste buds of rats and cultured on the surface of LAPS chip. Due to the unique advantages such as single-cell recording, light addressable capability, and noninvasiveness, LAPS chip was used as secondary transducer to monitor the responses of TRCs by recording extracelluar potential changes. The results indicate LAPS chip can effectively record the responses of TRCs to different bitter substances used in this study in a real-time manner for a long-term. In addition, by performing principal component analysis on the LAPS recording data, different bitter substances tested can be successfully discriminated. It is suggested this TRCs-LAPS hybrid biosensor could be a valuable tool for bitter substance detection. With further improvement and novel design, it has great potentials to be applied in both basic research and practical applications related to bitter taste detection.

To increase the application potential in manufacturing process, such as monitoring the processing performance, the profile measurement should be provided in real-time display and with high resolution simultaneously. We propose a line-field Fourier-domain interferometric method (LFI), which combines the line-field microscope with spectral interferometer, for the surface cross-sectional profile measurement with no scan needed. The white light and objectives are employed to offer high axial and lateral resolution, respectively. In our system setup, the measurement could be implemented in real-time display of 10 frame/s, and the resolutions of the LFI system in X; Y , and Z directions are ~8 μm, ~3.2 μm, and ~1.4 μm, respectively. As a demonstration, the cross-sectional profiles of a microfluidic chip are tested. The graphics processing unit is also used to accelerate the reconstruction algorithm to achieve the real-time display of the cross-sectional profiles.

Collagen is an endogenous fluorophore that accounts for about 70% of all proteins of human skin, so it can be an optical marker for structural abnormalities in tissues registered by laser fluorescent diagnostics in vivo. Using the examples of such abnormalities as scars, scleroderma and basal cell carcinoma, this study shows the differences between coefficients of fluorescent contrast kf e-T of abnormalities from the ones for healthy tissues at fluorescent excitation wavelength 360-380 nm. It is shown that scars and dysplasia are characterized by reduced values of kf e-T for collagen. Due to high turbidity and phase heterogeneousness as well as variation of parameters of blood microcirculation and concentrations of other related chromophores, there is no mathematical model that precisely calculates the concentration of collagen in tissues only with the use of the value of fluorescent signal intensity. So, probably, the best marker of the pathological process is a comprehensive representation of kf e-T for all endogenous fluorophores, i.e., for all used visible wavelengths. In this case identification of abnormal tissues is quite possible by detecting some deviations of coefficients kf e-T for the optically identical and symmetrical regions of the human body.

Multiwave laser medical device "Livadia" has been developed for bactericidal and therapeutic impact on the affected organism parts. This device is on the diode pumped solid-state laser and main wavelength radiation conversion 1064 nm into the second harmonic 532 nm and fourth harmonic 266 nm. It has been shown that UV radiation on the wavelength 266 nm on bronchia mucosa with various inflammation types improves regenerative processes in bronchia tissues which decreases treatment deadline.