Comparison of perceptual learning of real and virtual line orientations: An event-related potential study

AbstractWhen investigating perceptual learning (PL), most researchers use real figures as stimuli, but PL can occur when subjects are trained with virtual stimuli or even without any visual stimuli at all. Here, we first demonstrated that virtual lines have the same perceptual attributes as real lines by confirming that there is also an oblique effect in virtual lines (formed by a pair of circles) in an orientation discrimination task. Then, our ERP study showed that orientation discrimination learning and its transfer across real and virtual lines were associated with more negative parietal–occipital P1–N1 (reduced P1 and enhanced N1), which indicated the involvement of high-level stages of visual information processing or the involvement of top-down influences. At the same time, the specific ERP changes in the frontal ERP components were differently associated with real versus virtual line orientation learning. That is, real line learning was characterized by an early and short-lasting frontal N1 (120–140ms) reduction, in contrast to a much later, widespread, and long-lasting P150–300 decrease in virtual line learning. These results contribute to the understanding of the neural basis of perceptual learning and the distinction between real and virtual stimulus learning

A study on the extraction and purification technology of tea sapogenin

In order to extract and purify tea sapogenin, first the extraction liquid is obtained using mechanically pressed tea-seeds as raw material, which will be decreased by organic solvent. When the conditions like the methanol volume fraction is 75v/v, solid-liquid is 1:4 and the ultrasonic frequency is 25.8 Hz, extract them for 30 min. After this, collect the extraction liquid and slowly add in Hz-841 macroporous resin column, then elute it with 0.3% NaOH. The third step is to elute with ethanol of different concentrations after the coloring pigment is got rid of, and then detect it with thin layer chromatography (TLC). It is discovered that there is only tea sapogenin in the 35 – 95v/v ethanol elution liquid. The last step is to collect the 95% ethanol elution liquid and vacuum condense it; and then tea-Tea sapogenin with a purity of 96% can be obtained

The psychometric properties of the quick inventory of depressive symptomatology-self-report (QIDS-SR) in patients with HBV-related liver disease

Background: Comorbid depression in Hepatitis B virus (HBV) is common. Developing accurate and time efficient tools to measure depressive symptoms in HBV is important for research and clinical practice in China. Aims: This study tested the psychometric properties of the Chinese version of the 16-item Quick Inventory of Depressive Symptomatology (QIDS-SR) in HBV patients. Methods: The study recruited 245 depressed patients with HBV and related liver disease. The severity of depressive symptoms was assessed with the Montgomery-Asberg Depression Rating Scale (MADRS) and the QIDS-SR. Results: Internal consistency (Cronbach’s alpha) was 0.796 for QIDS-SR. The QIDS-SR total score was significantly correlated with the MADRS total score (r=0.698, p. Conclusions: The QIDS-SR (Chinese version) has good psychometric properties in HBV patients and appears to be useful in assessing depression in clinical settings

Automated identification of 2612 late-k and M dwarfs in the LAMOST commissioining data using the classification template fits

We develop a template-fit method to automatically identify and classify late-type K and M dwarfs in spectra from the LAMOST. A search of the commissioning data, acquired in 2009-2010, yields the identification of 2612 late-K and M dwarfs. The template fit method also provides spectral classification to half a subtype, classifies the stars along the dwarf-subdwarf metallicity sequence, and provides improved metallicity/gravity information on a finer scale. The automated search and classification is performed using a set of cool star templates assembled from the Sloan Digital Sky Survey spectroscopic database. We show that the stars can be efficiently classified despite shortcomings in the LAMOST commissioning data which include bright sky lines in the red. In particular we find that the absolute and relative strengths of the critical TiO and CaH molecular bands around 7000A are cleanly measured, which provides accurate spectral typing from late-K to mid-M, and makes it possible to estimate metallicities in a way that is more efficient and reliable than with the use of spectral indices or spectral-index based parameters such as zeta. Most of the cool dwarfs observed by LAMOST are found to be metal-rich dwarfs. We use a calibration of spectral type to absolute magnitude and estimate spectroscopic distances for all the stars; we also recover proper motions from the SUPERBLINK and PPMXL catalogs. Our analysis of the estimated transverse motions suggests a mean velocity and standard deviation for the UVW components of velocity to be: U=-9.8 km/s; V=-22.8 km/s; W=-7.9 km/s. The resulting values are general agreement with previous reported results, which yields confidence in our spectral classification and spectroscopic distance estimates, and illustrates the potential for using LAMOST spectra of K and M dwarfs for investigating the chemo-kinematics of the local Galactic disk and halo.Comment: 18 pages,16 figures,accepted for publication A

Second-order-like cluster-monomer transition within magnetic fluids and its impact upon the magnetic susceptibility

The low-field (below 5 Oe) ac and dc magnetic response of a magnetic fluid [MF] sample in the range of 305 to 360 K and 410 to 455 K was experimentally and theoretically investigated. We found a systematic deviation of Curie's law, which predicts a linear temperature dependence of inverse initial susceptibility in the range of our investigation. This finding, as we hypothesized, is due to the onset of a second-order-like cluster-to-monomer transition with a critical exponent which is equal to 0.50. The susceptibility data were well fitted by a modified Langevin function, in which cluster dissociation into monomers, at the critical temperature [T*], was included. In the ac experiments, we found that T* was reducing from 381.8 to 380.4 K as the frequency of the applied field increases from 123 to 173 Hz. In addition, our ac experiments confirm that only monomers respond for the magnetic behavior of the MF sample above T*. Furthermore, our Monte Carlo simulation and analytical results support the hypothesis of a thermal-assisted dissociation of chain-like structures