• Natural Product Sciences
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• v.17 no.1
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• pp.10-13
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• 2011

As parts of our continuing search for biologically active compounds from medicinal plants, we investigated the constituents of the seeds of Amomum xanthioides and isolated a sesquiterpenoid, a nerolidol derivative from its MeOH extract. The chemical structure was determined by spectroscopic methods, including 1D and 2D NMR to be ($2S^*$,$2'R^*$,$5'S^*$)-2-(5'-ethenyltetrahydro-5'-methylfuran-2'-yl)-6-methylhept-5en-2-ol (1). Compound 1 was isolated for the first time from nature source. Compound 1 exhibited a good cytotoxicity against SK-OV-3 and SK-MEL-2 cells ($IC_{50}$: 16.7 and $8.6\;{\mu}M$, respectively) using a SRB bioassay. In this study, we also determined the absolute configuration of 2 reported in previous paper.

• Archives of Pharmacal Research
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• v.29 no.2
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• pp.131-134
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• 2006

A new compound 2 and two known guaiane-type sesquiterpenoids were isolated from the methylene chloride-soluble fraction of the methanolic extract of the fruits of Torilis japonica (Umbelliferae) through repeated silica gel and Sephadex LH-20 column chromatography. Their chemical structures were elucidated as torilin (1), 11-acetoxy-8-angeloyloxy-$1{\beta}$-hydroxy-4-guaien-3-one ($1{\beta}$-hydroxytorilin, 2), and 11-acetoxy-8-angeloyloxy-$1{\alpha}$-hydroxy-4-guaien-3-one ($1{\alpha}$-hydroxytorilin, 3) by spectroscopic analysis. Compounds 1-3 exhibited cytotoxicity against human A549, SK-OV-3, SK-MEL-2, and HCT15 tumor cells.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.256.1-256.1
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• 2002

We investigated the anti-proliferative effects of a new compound. ircinin-1. from the sponge Sarcotragus sp. on SK-MEL -2 human skin cancer cells. From the data of MTT assay, cell viability was decreased by ircinin-1 in a dose-dependent manner. We observed that the anti-proliferative effect of ircinin-1 was due to the induction of apoptosis, which was confirmed by observing the morphological changes. the increased ratio of pro-apoptotic protein Bax to anti-apoptotic protein Bcl-2, and cleavage of poly(ADP-ribose) polymerase protein, via activation of caspase-3. (omitted)

• Journal of Information Processing Systems
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• v.20 no.1
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• pp.13-23
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• 2024

Music brings pleasure and relaxation to people. Therefore, it is necessary to classify musical genres based on scenes. Identifying favorite musical genres from massive music data is a time-consuming and laborious task. Recent studies have suggested that machine learning algorithms are effective in distinguishing between various musical genres. However, meeting the actual requirements in terms of accuracy or timeliness is challenging. In this study, a hybrid machine learning model that combines a deep residual auto-encoder (DRAE) and support vector machine (SVM) for musical genre recognition was proposed. Eight manually extracted features from the Mel-frequency cepstral coefficients (MFCC) were employed in the preprocessing stage as the hybrid music data source. During the training stage, DRAE was employed to extract feature maps, which were then used as input for the SVM classifier. The experimental results indicated that this method achieved a 91.54% F1-score and 91.58% top-1 accuracy, outperforming existing approaches. This novel approach leverages deep architecture and conventional machine learning algorithms and provides a new horizon for musical genre classification tasks.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.46 no.1
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• pp.28-33
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• 2009

In the research of speech recognition, locating the beginning and end of a speech utterance in a background of noise is of great importance. The conventional methods for speech endpoint detection are based on two simple time-domain measurements-short-time energy, and short-time zero-crossing rate, which couldn't guarantee the precise results if in the low signal-to-noise ratio environments. This paper proposes a novel approach that finds the Lyapunov exponent of time-domain waveform. This proposed method has no use for obtaining the frequency-domain parameters for endpoint detection process, e.g. Mel-Scale Features, which have been introduced in other paper. Accordingly, this algorithm is low complexity and suitable for Digital Isolated Word Recognition System.

• Archives of Pharmacal Research
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• v.15 no.4
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• pp.356-359
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• 1992

The activity-oriented fractionation of Psoralea corylifolia led to an isolation of a (+) bakuchio 1 as an activ eprinciple of its antitumoral property in vitro 1 was observed to exhibit a mild cytotoxicity against five kinds of cultured human cancer cell lines, i. e. the A549, SK-OV-3, SK-MEL-2, XF-498 and HCT15. The synthesized 2, 3-epoxide of (+)-bakuchiol 3 showed the similar activity as the (+) bakuchiol 1, whereas the other oxidation derivatives 4 and 5 including the acetyl (+) bakuchiol 2 showed a decreased activity.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.190.1-190.1
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• 2003

A bioassay-guided fractionation of the stem bark extract of Eucommia ulmoides Oliver (Eucommiaceae) led to the isolation of three iridoid constituents, genipin (1), geniposide (3), geniposidic acid (4) as well as (${\pm}$)-guaiacylglycerol (2) and fatty acid mixtures as active ingredients of the extract responsible for the antitumoral property. The EtOAc soluble part and BuOH soluble part of the extract demonstrated a significant inhibition on the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system) and HCT-15 (colon) in vitro, whereas the remaining water soluble part exhibited a poor inhibition. (omitted)

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.570-580
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• 1996

Design and synthesis of novel 4-phenyl-1-arylsulfonylimidazolones 3 and 4-phenyl-3-arylsulfonylimidazolones 4 and evaluation of their cytotoxic activity against eleven human cancer cell lines and two murine leukemia cell lines in vitro were performed. As a result, a series of 4-phenyl-1(N)-arylsulfonylimidazolones (3) has been found to be the potential anticancer agent. Compounds 3b, 3c, and 3d exhibit strong activity as indicated by their $IC_{50}$ values 0.39, 3.19, $0.31{\mu}g/mL$ against A549 and 0.80, 0.48, $0.0007{\mu}g/mL$against SK-Mel-2, respectively. These compounds also possess much more potent activity (10-1000 times) than LY186641 against eleven other cell lines.

• Archives of Pharmacal Research
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• v.26 no.10
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• pp.840-845
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• 2003

Temperature change is one of the major environmental factors that influence the human skin. However, the relationship between temperature and melanogenesis has received little attention. In the present study, we investigated the effects of temperature change on melanogenesis in a mouse melanocyte cell line (Mel-Ab), and primary cultured human melanocytes. We found that Mel-Ab cells cultured at low temperatures (31 and 34$^{\circ}C$) produce less melanin than cells at 37$^{\circ}C$. These results were confirmed by experiments upon human melanocytes, demonstrating that the hypopigmenting effect of low temperatures is not cell type dependent. The observed melanin production was found to be accompanied by tyrosinase activity at each temperature, indicating that tyrosinase activity is regulated by temperature. We further examined whether the incubation period at low temperatures plays an important role in the regulation of melanogenesis. Short exposures to 27$^{\circ}C$ for 1 h or 3 h did not affect tyrosinase activity or melanin synthesis, whereas long exposures to 31$^{\circ}C$ for 2 days or 6 days significantly reduced tyrosinase activity and melanin synthesis in a duration-dependent manner. Our results suggest that exposure to low temperature and the duration of this exposure are important regulators of melanogenesis.

• Journal of Electrical Engineering and Technology
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• v.12 no.1
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• pp.373-377
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• 2017

This paper presents a voice-activity detection (VAD) method for sound sequences with various SNRs. For real-time VAD applications, it is inadequate to employ a post-processing for the removal of burst clippings from the VAD output decision. To tackle this problem, building on the bi-level hidden Markov model, for which a state layer is inserted into a typical hidden Markov model (HMM), we formulated a robust method for VAD not requiring any additional post-processing. In the method, a forward-inference-ratio test was devised to detect the speech endpoints and Mel-frequency cepstral coefficients (MFCC) were used as the features. Our experiment results show that, regarding different SNRs, the performance of the proposed approach is more outstanding than those of the conventional methods.