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Electroencephalogram (EEG)-based emotion recognition is receiving significant attention in research on brain-computer interfaces (BCI) and health care. To recognize cross-subject emotion from EEG data accurately, a technique capable of finding an effective representation robust to the subject-specific variability associated with EEG data collection processes is necessary. In this paper, a new method to predict cross-subject emotion using time-series analysis and spatial correlation is proposed. To represent the spatial connectivity between brain regions, a channel-wise feature is proposed, which can effectively handle the correlation between all channels. The channel-wise feature is defined by a symmetric matrix, the elements of which are calculated by the Pearson correlation coefficient between two-pair channels capable of complementarily handling subject-specific variability. The channel-wise features are then fed to two-layer stacked long short-term memory (LSTM), which can extract temporal features and learn an emotional model. Extensive experiments on two publicly available datasets, the Dataset for Emotion Analysis using Physiological Signals (DEAP) and the SJTU (Shanghai Jiao Tong University) Emotion EEG Dataset (SEED), demonstrate the effectiveness of the combined use of channel-wise features and LSTM. Experimental results achieve state-of-the-art classification rates of 98.93% and 99.10% during the two-class classification of valence and arousal in DEAP, respectively, with an accuracy of 99.63% during three-class classification in SEED.

Although Codonopsis pilosula (C. pilosula) has long been considered as an important herbal medicine, no analytical method of marker compounds for quality assessment is registered in the Korean Pharmacopoeia. We developed a simple and robust analytical method of three marker components lobetyolin (1), lobetyol (2), and tangshenoside I (3) using HPLC-UV method. We also confirmed the three marker components using UPLC-qTOF/MS method. Various extraction conditions were optimized to achieve three marker compounds with faster extraction kinetics and higher recovery. The analytical condition was then validated by determining the linearity, accuracy, precision, limit of detection, limit of quantification, recovery, repeatability, robustness, and stability. By this method, the three markers were successfully quantified in 38 commercial samples along with three related species that are sometimes used as alternatives to C. pilosula. Finally, principal component and hierarchical clustering analyses were conducted to show the practicality of the method developed for the quality evaluation of C. pilosula.

The breast cancer resistance protein (BCRP) is a member of the ATP-binding cassette transporters. The aim of the present study was to identify genetic variants of BCRP in Koreans and to assess the functional consequences of BCRP polymorphisms. Twenty single nucleotide polymorphisms (SNP), including four nonsynonymous SNP, were identified by DNA sequencing of the BCRP gene in 92 Korean subjects. BCRP V12M, Q141K, P269S, and Q126Stop were detected at frequencies of 23, 28, 0.2, and 1.9%, respectively. These four coding variants were also screened in Chinese and Vietnamese subjects; the allelic frequencies among the three populations were compared; and predictions were made as to the potential frequency of each variant. In vitro functional analyses of the P269S protein and the promoter SNP -19031C>T (mutated in the hypoxia-inducible factor-1alpha binding site) were performed and compared with those of the wild type. P269S exhibited a 35 to 40% decrease in vesicular uptake of [(3)H]estrone-3-sulfate and [(3)H]methotrexate compared with the wild type. The promoter SNP -19031C>T did not affect BCRP promoter activity in either the presence or absence of chemical-induced hypoxic stress. Our results suggest that the P269S variant could be a functionally altered variant. Genotyping of this variant in clinical studies is needed to address its phenotypic role. Genetic polymorphisms of BCRP were found to be very common in Koreans, as well as in other ethnic groups. Comparative analyses among three Asian populations revealed different frequencies for the four functional BCRP variants.