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Brain 'Computer Interface (BCI) is an emerging technology for communication between human brain and external devices. The traditional feature extraction method based on time-frequency characteristics cannot reflect the nonlinear characteristics of EEG signals. In order to further improve the accuracy of classification, the pretreatment method of wave threshold denossing is firstly used to improve the signal-to-noise ratio of EEG signals. Then, the feature extraction of the three kinds of imaginary motion EEG signal is carried out by the parameter-sample entropy of nonlinear dynamics, and the nonlinear features of EEG signal are preserved. Among them, the research of Motor-Imagery (MI) EEG has always been the focus of BCI that is a highspeed development field. This paper studies three classifiers including support vector machine, LVQ neural network and BP neural network. The experimental results show that BP neural network has higher recognition rate for classification and recognition of EEG signal. [ABSTRACT FROM AUTHOR]

Mild cognitive impairment(MCI)has a high risk of progressing to dementia,with no recommended therapies.Recent studies have shown that meditation has huge potential to improve the cognitive function,with low cost and high safety,being suitable to be applied in the treatment of neurological and psychotic disorders.This paper reviews the application and prospects of meditation in treating MCI from the concept,clinical efficacy,and mechanism of meditation,aiming to provide reference for future clinical studies.

The vibrational energy transfer from vibrational levels of RbH(X 1sigma+, v = 0-2) by collision with H2 was determined using the integrated time-resolved laser induced fluorescence (LIF) in a five-arm crossed heat-pipe oven. Rb-H2 mixture was irradiated with pulses of 696.4 nm radiation from a OPO laser, populating 6D state by two-photon absorption. The vibrational levels of RbH(X 1sigma+) generated in the reaction of Rb(6D) and H2 were detected by LIF technique. The nascent quantum state distributions of RbH were obtained when the delay time between the pump and probe laser was 20 ns. The nascent RbH product molecules were found to populate the lowest three vibrational (v = 0, 1, 2) levels of the ground electronic state but could not be detected in any higher vibrational state. The integrated time-resolved LIF excited A 1sigma+ --> X 1sigma+ system in the presence of H2 was recorded with delay time from 0 to 10 micros. The RbH signal of v = 0, 1 levels first increased and then decreased on a larger time scale. RbH was created instantaneously then was quenched by collision and diffused. The rate equations for the population of the vibrational levels were given. The integrated profiles method permitted us to determine the rate coefficients for vibrational transfer of RbH(X 1sigma+, v = 0-2) by collision with H2. The rate coefficients for collisional transfer of RbH(X 1sigma+) by collisions with H2 are (in units of 10-(11) cm3 x s(-1)) 3.4 +/- 0.8 and 2.8 +/- 0.6 for v = 2 --> v = 1 and v = 1 --> v = 0 respectively. The diffusion rates of v = 0, 1, 2 are (in units of 10(5) s(-1)) 4.9 +/- 1.1, 1.0 +/- 0.3 and 0.6 +/- 10.2, respectively. The experiment showed that vibrational relaxation from RbH(X 1sigma+, v = 0-2) was more efficient compared to that of other vibrational levels studied here.

Pure potassium vapor or K-H2 mixture was irradiated in a glass fluorescence cell with pulses of 710 nm radiation from an OPO laser, populating K2 (1lambda(g)) state by two-photon absorption. Cross sections for 1lambda(g)-3lambda(g) transfer in K2 were determined using methods of molecular fluorescence. During the experiments with pure K vapor, the cell temperature was varied between 553 and 603 K. The K number density was determined spectroscopically by the white-light absorption measurement in the blue wing of the self-broadened resonance D2 line. The resulting fluorescence included a direct component emitted in the decay of the optically excitation and a sensitized component arising from the collisionally populated state. The decay signal of time-resolved fluorescence from1lambda(g) -->1 1sigma(u)+ transition was monitored. It was seen that just after the laser pulse the fluorescence of the photoexcited level decreased exponentially. The effective lifetimes of the 1lambda(g) state can be resolved. The plot of reciprocal of effective lifetimes of the 1lambda(g) state against K densities yielded the slope that indicated the total cross section for deactivation and the intercept that provided the radiative lifetime of the state. The radiative lifetime (20 +/- 2) ns was obtained. The cross section for deactivation of the K2(1lambda(g)) molecules by collisions with K is (2.5 +/- 0.3) x 10(-14) cm2. The time-resolved intensities of the K23lambda(g) --> 1 3sigma(u)+ (484 nm) line were measured. The radiative lifetime (16.0 +/- 3.2) ns and the total cross section (2.5 +/- 0.6) x 10(-14) cm2 for deactivation of the K2 (3lambda(g)) state can also be determined through the analogous procedure. The time-integrated intensities of 1lambda(g) --> 1 1sigma(u)+ and 3lambda(g) --> 1 3sigma(u)+ transitions were measured. The cross section (1.1 +/- 0.3) x10(-14) cm2 was obtained for K2 (1lambda(g))+ K --> K2 (3lambda(g)) + K collisions. During the experiments with K-H2 mixture, the cell temperature was kept constant at 553 K. The H2 pressure was varied between 40 and 400 Pa. The effects of K2-K collisions could not be neglected. These effects were subtracted out using the results of the pure K experiments. The cross section (2.7 +/- 1.1) x 10(-15) cm2 was obtained for K2 (1lambda(g)) + H2 --> K2 (3lambda(g))+H2 collisions. The cross section is (6.8 +/- 2.7) x 10(-15) cm2 for K2 (3lambda(g)) + H2 --> states out of K2 (3lambda(g)) + H2 collisions.

A low-power tunable laser was used to populate the Rb(5P(3/2)) hyperfine-structure levels in a pure optically thick vapour in the presence of a dissipative surface. The retrofluorescence intensities and spectrum profile for the 780 nm (5P(3/2)--> 5S(1/2)) and 795 nm (5P(1/2)-->5S(1/2)) lines were measured and analyzed. The glass-vapor interface was considered as two distinct regions, a wavelength-thickness vapor layer adjacent to the surface and a more remote vapor region The first region was analyzed as a spectral filter that annihilated the absorbed photons and the second one as a rich spectral light source. The authors discussed two possible mechanisms for the 5P(1/2) population in the cell [i.e., mechanism(1): collisions Rb(5P(3/2))+Rb(5S(1/2))-->Rb(5P(1/2))+Rb(5S(1/2)); mechanism(2): collisions Rb(5D)+Rb(5S)-->Rb(5P)+Rb(5P)]. For each one of the possible mechanisms considered, the authors gave the theoretical formulation of the retrofluorescence integrated signal associated with 795 nm(5P(1/2)-->5S(1/2)), which was compared with experiment. Two important characteristic aspects of retrofluorescence spectra must be taken into account when dealing with retrofluorescence signals for atomic process investigation: the retrofluorescence intensity dependence on laser power and sensitized laser retrofluorescence line shapes. When the laser frequency is scanned through the hyperfine resonance line, the sensitized retrofluorescence spectra signal corresponding to the 795 nm line has a profile similar to the profile of the retrofluorescence signal at the 780 nm. The authors have pointed out that mechanism(1) gives the linear dependence of the trtrofluorescence as a function of laser power and the spectrum profile. The population of the 5P(1/2) atomic level in an optically thick vapour can be principally explained by the fine-structure excitation transfer process [mechanism(1)]. It appears from our experimental and theoretical investigations that, the spectral properties of the laser-induced Rb 795 nm sensitized retrofluorescence in a pure optically thick vapour near a dissipative surface cannot be explained by the mechanism(2).

Objective: To construct RNAi recombinant adenoviral expressive vectors specific to glycogen synthase kinase-3beta (GSK-3beta) and to observe its gene knockdown effect on the expression of GSK-3beta, and to explore the effect of Wnt/beta-catenin pathway on the proliferation of human thyrocytes using the RNAi adenovirus vector., Methods: An adenovirus plasmid that contained the RNAi cassette targeting the GSK-3beta gene was constructed by homologous recombination and cloning techniques, transfected into human embryo kidney (HEK) 293A cells to product adenovirus, and then was used to infect the HEK293A cells to amplify the adenoviral stock. Plaque forming assay was used to titer the adenoviral stock. Normal human thyrocytes fart from thyroid adenoma were obtained during resection of adenoma, cultured, and infected by the GSK-3beta specific RNAi adenovirus. The GSK-3beta gene silencing effect induced by the RNAi adenovirus was detected by Western blotting 0, 24, 48, 72, 120, and 144 hours later. BrdU method was used to detect the cell proliferation. Another HEK293A cells were divided into 3 groups: infected with recombinant adenovirus plasmid Ad-1457, infected with un-recombinant framework plasmid pAd-DEST, and un-infected. 72 hours later Western blotting was used to examine the level of beta-catenin., Results: The GSK-3beta expression of the thyrocytes infected with the recombinant adenovirus plasmid Ad-1457 were significantly lower than those of the thyrocytes infected with Ad-DEST (all P<0.05). The expression of beta-catenin of the thyrocytes infected with Ad-DEST was significantly higher than those of the Ad-DEST group and un-infected group (both P<0.05). BrdU assay suggested that the proliferation rates 1, 3, 5, and 7 days after infection of the thyrocytes infected with Ad1457 plasmid were significantly higher than those of the thyrocytes infected with the plasmid pAd-DEST (all P<0.05)., Conclusion: RNAi adenovirus is an important tool inhibiting the expression of target gene efficiently. The Wnt/beta-catenin pathway plays an important role in the regulation of proliferation of human thyrocytes.

The radiation of a laser photoexcited Rb atoms from the ground state to the 5P3/2 level in a mixture of Rb vapor and hydrogen. The energy-pooling collision 5P3/2 + 5P3/2 --> 5S1/2 + 5D producted 5D state. The Rb (5P3/2) density and spatial distribution were mapped by monitoring the absorption of a counter-propagating laser beam, tuned to the 5P3/2 --> 7S1/2 transition, which could be translated parallel to the pump beam. In the presence of radiation trapping, the spontaneous radiation rate is multiplied by the transmission factor T5P3/2 --> 5S1/2, which describes the average probability that photons emitted within the fluorescence detection region can pass through the optically thick vapor without being absorbed. The T5P3/2 --> 5S1/2 is related to the frequency dependent absorption cross section and the density and spatial distribution of atoms in the level of the transition. The effective radiative rates of the Rb D2 line as a function of the H2 pressure were obtained. These quantities were combined with the measured excited atom density and fluorescence ratio to yield absolute energy-pooling rate coefficient. The quenching collision Rb (5P3/2) + H2 (v = 0) --> Rb(5S) + H2 (v = 2) producted state H2 (v= 2). This process is at least 16 times faster than the Rb (5P3/2) radiative decay rate. The reverse process of this process is relatively unlikely due to their large translational energy defect. The cross section for the process H2 (v = 2) + H2 (v = 0) --> H2 (vn = 1) + H2 (v = 0) + 3 920.2 cm(-1) is 7.7 x 10(-19) cm2. Hence the relaxation rate of this vibrational level is relatively slow and the nuclear spin statistics is conserved. The H2 (v = 2) density was determined by using the cross section for Rb (5P3/2)-H2 quenching. RbH was fromed by the Rb(5D) + H2 and Rb (5P3/2) + H2 (v = 2) reactions and observed by laser absorption. The ratio of 5D --> 5P3/2 to 5P3/2 --> 5S1/2 fluorescence was measured as a function of the H2 density. The absorption of the laser beam tuned to the X1sigma+ --> A1sigma+ line of RbH was also measured as a function of the H2 density. From these measurements we obtained the cross section of 4.02 x 10(-7) cm2 for the process Rb (5D) + H2 --> RbH + H. The cross section for Rb (5P3/2) + H2 (upsilon = 2) --> RbH + H is 1.00 x 10(-8) cm2. This experiment showed that under our experimental conditions, RbH molecules are not created by a direct interaction of Rb(5P) with H2 but through a two-step reaction.

Background & Objective: The chemokine receptor CXCR4 and its sole ligand stromal cell-derived factor-1 (SDF-1) not only actively participate in inflammation, hematopoiesis, infection of HIV, but also play a pivotal role in migration, invasion and metastasis of some malignant tumors. This study was to investigate the role of CXCR4/SDF-1 axis in mediating metastasis in cervical cancer cells through activating the mitogen-activated protein kinase (MAPK) pathway and its possible mechanism., Methods: Intracellular calcium mobilization was observed under laser scanning confocal fluorescence microscopy. The phospharylation of extracellular signal-regulated kinase (ERK) 1/2 in HeLa cells after binding of SDF-1alpha to CXCR4 was measured by Western blot. Adhesion of CXCR4/SDF-1 to cervical cancer cells and secretion of matrix metalloproteinase (MMP) were detected by adhesion assay and gelatin zymography, respectively., Results: After SDF-1alpha was bound to CXCR4, a rapid and robust mobilization of intracellular calcium in Hela cells was initiated. The difference between the average baseline fluorescence intensity (FI) and the peak FI was significant (P < 0.01). ERK-1/2 was rapidly phosphorylated in Hela cells after its exposure to SDF-1alpha, and the strongest phosphorylation occurred at 30 min. The adhesion ability of Hela cells to fibronectin (FN) and laminin (LN) was increased after SDF-1alpha treatment (P < 0.05 and P < 0.01, respectively), while pretreatment of Hela cells with an ERK-1/2 inhibitor, PD98059, decreased adhesion of Hela cells to extracellular matrix (ECM) with the presence of SDF-1alpha (P < 0.05). Increased amounts of active MMP-2 were secreted in response to increased SDF-1alpha concentrations. When the concentration of SDF-1alpha was 800ng/mL, the secretion of active MMP-2 reached the peak and started to decrease afterwards., Conclusion: CXCR4/SDF-1 participates in tumor invasiveness and metastasis in cervical cancer through regulating the adhesion ability by activating the MAPK signaling transduction pathway and promoting secretion of MMP-2.

The effective radiation rate for Cs (6P3/2) resonance level in the presence of helium was determined. A cell filled with Cs metal and He at pressure P(He) (0-500 Pa) was established at T = 300 K. The cell was heated in the temperature range between 330 and 370 K, which produced Cs number densities approximately in the range between 10(12) and 10(13) cm(-3). Cs atoms were excited to the 6P3/2 state using a single-mode diode laser(pump laser). The transmission of the medium at the center of the Doppler envelope of the strong h. f. component of the CsD2 line due to hyperfine pumping alone amounts to approximately 5%. The assumption that has been made is that the lower-state hyperfine levels are populated in a statistical ratio. The excited-atom density and spatial distribution were mapped by monitoring the absorption of a counterpropagating single-mode diode laser beam (probe laser) tuned to the 6P3/2 --> 8S1/2 transition which could be translated parallel to the pump beam. In the presence of radiation trapping, the spontaneous radiation rate is multiplied by the transmission factor T6P3/2 -->1/2, which describes the average probability that photons emitted within the fluorescence detection region can pass through the optically thick vapor without being absorbed. The T6P3/2 --> 6S1/2 is related to the frequency dependent absorption cross section and the density and spatial distribution of atoms at the level of the transition. Position dependent 6P3/2 state densities were combined with the collisional broadening rate of 6P3/2 <-- 6S1/2 line due to the perturbation of both helium and cesium to yield T6P3/2 --> 6S1/2. The effective radiation rates of the Cs D2 line as a function of the He pressure P(He) were obtained. The helium caused line broadening and therefore increased the effective radiation rate. The fluorescence intensity I852 of the 6P3/2 --> 6S1/2 emission was measured simultaneously. The measured fluorescence ratios determined the ratios of the effective radiation rates at different He density. These ratios are in agreement with theoretical evaluation.

Aim: To investigate the effect of the overall alkali of Traditional Chinese Medicine tongbiling(TBL) which comprises brucine and strychnine alkaloids on collagen induced-arthritis(CIA) and study its paharmacological mechanisms of cellular immunity., Methods: Bovine CII was emulsified in Freund's incomplete adjuvant. Wistar rats were injected with Type II collagen intradermally at the base of the tail. After swelling, CIA groups were, randomly divided into physiological saline group and treatment group. Then the swelling of the rats' hindlimbs was evaluated. The whole body of the rats treated on 35 th days was photographed by mammography X-Ray. 96 joints in erosion scoring system and 100 joints in joint spacing narrow(JSN) scoring system were used to observe the joint destruction of CIA from X-Ray comprehensively and objectively. After the rats were killed, the third proximal claw pad of the right hindlimb and left forelimb were stained by HE dying, Neutrophil, lymphocyte, plasmacyte infiltration and hyperplasia of synoviocytes were assessed. Then MTT and Western blot were used to determine the effect of the overall alkali of TBL on proliferation of Jurkat cells and ERK1/2 phosphorylation of Jurkat cells, respectively., Results: Inflammation of CIA joints was aggravated quickly. The swelling of CIA rats treated by MTX and overall alkali of TBL for 35 days was relieved (P<0.05). MTX and overall alkali of TBL inhibited the hyperplasia of synoviocytes. Overall alkali of TBL inhibited the infiltration of lymphocyteS and plasmacytes. Overall alkali of TBL inhibited the proliferation and ERK1/2 phosphorylation of Jurkat cells., Conclusion: Overall alkali of TBL could relieve joint inflammation and destruction of CIA rats by blocking the MAPK cell signalling pathway to inhibit the activation and proliferation of T cells. Our study might provide an experimental basis for treatment of rheumatoid arthritis with overall alkali of TBL.