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Previous behavioral research has proved that individuals process own- and other-race faces differently. One well-known effect is the other-race effect (ORE), which indicates that individuals categorize other-race faces more accurately and faster than own-race faces. The existed functional magnetic resonance imaging (fMRI) studies of the other-race effect mainly focused on the racial prejudice and the socio-affective differences towards own- and other-race face. In the present fMRI study, we adopted a race-categorization task to determine the activation level differences between categorizing own- and other-race faces. Thirty one Chinese participants who live in China with Chinese as the majority and who had no direct contact with Caucasian individual were recruited in the present study. We used the group independent component analysis (ICA), which is a method of blind source signal separation that has proven to be promising for analysis of fMRI data. We separated the entail data into 56 components which is estimated based on one subject using the Minimal Description Length (MDL) criteria. The components sorted based on the multiple linear regression temporal sorting criteria, and the fit regression parameters were used in performing statistical test to evaluate the task-relatedness of the components. The one way anova was performed to test the significance of the component time course in different conditions. Our result showed that the areas, which coordinates is similar to the right FFA coordinates that previous studies reported, were greater activated for own-race faces than other-race faces, while the precuneus showed greater activation for other-race faces than own-race faces.

The purpose of this paper is to compare between EEG source localization and fMRI during emotional processing. 108 pictures for EEG (categorized as positive, negative and neutral) and 72 pictures for fMRI were presented to 24 healthy, right-handed subjects. The fMRI data were analyzed using statistical parametric mapping with SPM2. LORETA was applied to grand averaged ERP data to localize intracranial sources. Statistical analysis was implemented to compare spatiotemporal activation of fMRI and EEG. The fMRI results are in accordance with EEG source localization to some extent, while part of mismatch in localization between the two methods was also observed. In the future we should apply the method for simultaneous recording of EEG and fMRI to our study.

We propose a new method for the analysis of functional magnetic resonance imaging (fMRI) which is called functional feature subspace mapping (FFSM). We mainly focused on the experimental design with periodic stimuli which can be described by a number of Fourier coefficients in the spectral domain. Then the subspace is obtained through the dimension reduction technique. Finally, the presence of activated time series is identified by the clustering method. Experiments with simulated data and the real human experiments are conducted to demonstrate that the algorithm we proposed is feasible. Although we focus on analyzing periodic fMRI data, the approach could be extended to analyze non-periodic fMRI data (event-related fMRI) by replacing the spectral analysis with a wavelet analysis.

Clinical application shows that the Q-switched laser therapy on pigmented lesions based on the principle of selective thermolysis is good in efficiency. But the mechanism of this method of treatment remains unclear yet. Elementary researches are up to date restricted to the levels of morphological observation mainly. The beginning split second process within which laser pulse is interaction with dermal tissues has not been investigated in detail. This process also includes a series of sub processes of super high intensity of photo thermotics, plasma shock wave, super express boil inflation, et. Researches of experimental tests to the momentary processes mentioned above have been performed in this project. The results suggest that laser ablation impact and shock wave induced by laser play important rules in the process.

Experimental investigation on cerebral damage of adult SD rats induced by 532nm CW laser was performed. Tissue heat conductive equation was set up based on two-layered structure model. Finite difference algorithm was utilized to numerically simulate the temperature distribution in the brain tissue. Allowing for tissue response to temperature variation, free boundary model was used to discuss tissue thermal coagulation formation in brain. Experimental observations show that thermal coagulation and necrosis can be caused due to laser light absorption. The result of the calculation shows that the process of the thermal coagulation of the given mode comprises two stages: fast and slow. At the first stage, necrosis domain grows fast. Then necrosis domain growth becomes slower because of the competition between the heat diffusion into the surrounding undamaged tissue and the heat dissipation caused by blood perfusion. At the center of coagulation area no neuron was observed and at the transitional zone few nervous cells were seen by microscope. The research can provide reference data for developing clinical therapy of some kind of encephalic diseases by using 532nm laser, and for making cerebral infarction models in animal experiment.

With the increase of people’s living standard and the changes of living form, the number of people who suffer from hypercholesterolemia is increasing. It is not only harmful to heart and blood vessel, but also leading to obstruction of cognition. The conventional blood detection technology has weakness such as complex operation, long detecting period, and bad visibility. In order to develop a new detection method that can checkout hypercholesterolemia conveniently, spectroscopy of cholesterol in hypercholesterolemia serum is obtained by the multifunctional grating spectrograph. The experiment results indicate that, under the excitation of light-emitting diode (LED) with the wavelength at 407 nm, the serum from normal human and the hypercholesterolemia serum emit different fluorescence spectra. The former can emit one fluorescence region with the peak locating at 516 nm while the latter can emit two more regions with peaks locating at 560 nm and 588 nm. Moreover, the fluorescence intensity of serum is non-linear increasing with the concentration of cholesterol increases when the concentration of cholesterol is lower than 13.8 mmol/L, and then, with the concentration of cholesterol increase, the fluorescence intensity decreases. However, the fluorescence intensity is still much higher than that of serum from normal human. Conclusions can be educed from the experiments: the intensity and the shape of fluorescence spectra of hypercholesterolemia serum are different of those of normal serum, from which the cholesterol abnormal in blood can be judged. The consequences in this paper may offer an experimental reference for the diagnosis of the hypercholesterolemia.

In order to investigating the effect of wavelength on laser blood therapy, we test the fluorescent spectra of human blood. The wavelengths of exciting lights are 530 nm and 632.8 nm respectively. The result indicates that the light of 530 nm induces much stronger fluorescence, and the emitting spectra induced by 632.8 nm is rather different from the spectra induced by the light of 530 nm. This result suggests that the processes of interaction between laser and blood vary with the wavelength of the radiating lights, so the biological effects of the light to blood can differ with wavelength. These facts might have some meanings to the further research for explaining mechanisms of the laser blood therapy.

The technique of fluorescence spectroscopy is applied to study thioredoxin reductast (TrxR) in the cells of human brain. Experimental results show that, by the ultraviolet light irradiation (λmax=253.7nm), TrxR is able to emit two striking spectral bands of 287nm to 484nm and 560nm to 720nm. The spectral profile also consists of some narrow spike-like bands atop these two broad bands. With the concentration of TrxR decreases, the narrow spike-like bands disappear little by little. Furthermore, physical and biochemical mechanisms of fluorescence production for ultraviolet light-induced TrxR spectra and its characteristics are analyzed. The new spectroscopic information suggested in this paper may represent an effort of better understanding of the structure and conformation changes of TrxR.

Native fluorescence spectral characteristics of red blood cells were studied in the visible region in this paper. Blood samples were collected from normal small albino rats. Native fluorescence spectra of the erythrocyte were induced using Light Emitting Diode (LED) at yellow wavelength about 570+/- 16 nm ((Delta) (lambda) 0.5approximately equals 32nm). As the rat's erythrocyte content of in physiological water is increasing, the fluorescent primary emission peak is red shifted from 588 nm to above 615 nm. Furthermore, the fluorescence intensity at about 600 nm was found to be maximal while the rat's erythrocyte consistence is 1%. Moreover, it is shown in large numbers of experiments that LED-induced fluorescence spectra of the erythrocyte are similar with the whole blood. It may make sense for low- intensity light therapy.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.