Electroencephalogram-Based Emotion Recognition Using a Particle Swarm Optimization-Derived Support Vector Machine Classifier.

We sort human emotions using Russell's circumplex model of emotion by classifying electroencephalogram (EEG) signals from 25 subjects into four discrete states, namely, happy, sad, angry, and relaxed. After acquiring signals, we use a standard database for emotion analysis using physiological EEG signals. Once raw signals are pre-processed in an EEGLAB, we perform feature extraction using Matrix Laboratory and apply discrete wavelet transform. Before classifying we optimize extracted features with particle swarm optimization. The acquired set of EEG signals are validated after finding average classification accuracy of 75.25%, average sensitivity of 76.8%, and average specificity of 91.06%.

Wound healing promoting activity of stem bark extract of Semecarpus anacardium using rats.

The wound healing promoting property of stem bark methanol extract of Semecarpus anacardium was evaluated at three different dosages by excision, incision and dead space wound models using Wistar albino rats. Framycetin skin ointment was used as standard. LD(50) of methanol extract was determined to be 500 mg kg(-1). In methanol extract (20% ointment) treated group, epithelialisation of the incision wound was faster with a high rate of wound contraction. The tensile strength of the incision wound was significantly increased when compared to other treated groups. The histological examination of the dead space wound model granulation tissue of the methanol extract (100 mg kg(-1)) treated group showed increased cross-linking of collagen fibres and absence of monocytes as compared to control. Methanol extract at 100 mg kg(-1) exhibited significant wound healing activity but was lesser than standard; whereas, in animals treated with 50 and 75 mg kg(-1) showed moderate activity. This investigation supported the ethnomedicinal claims of S. anacardium.

Analgesic activity and acute toxicity study of Semecarpus anacardium stem bark extracts using mice.

BACKGROUND: The analgesic activity of petroleum ether, chloroform and methanol extracts of Semecarpus anacardium was investigated by tail flicking and writhing method using acetyl salicylic acid as the standard reference. MATERIALS AND METHODS: The staircase method was adopted for the determination of the acute toxicity. LD(50) of the petroleum ether extract and the chloroform extract was 700 mg/kg; however, the LD(50) for the methanol extract was 500 mg/kg. After 1 h of oral administration of the extracts, 0.6% acetic acid was administered intraperitoneally and the analgesic activity was evaluated. RESULTS: The number of writhing observed in the control group was 73.33 writhes. The methanol extract showed a significant analgesic activity, with 28.33 writhes, than the petroleum ether extract and the chloroform extract. But, all the extracts showed proved to be less potent than the standard drug which showed 2.33 writhes. Animals pretreated with saline did not show a signify cant effect on the latent period of tail-flick response. The analgesic effect of the petroleum ether extract was comparatively less evident. The maximum possible analgesia (MPA) increased up to 9.1% which remained elevated above the basal levels throughout the observation period. The MPA calculated for the chloroform extract increased to 14.03%. However, the analgesic effect of the methanol extract was also observed at 0.5 h following oral administration and the effect remained significant throughout the 3 h observation period, and was increased to 20.43%. CONCLUSION: Consistent analgesic activity of all the three S. anacardium extracts was observed by both the methods. The methanol extract was more potent than the petroleum ether and chloroform extracts but was less effective than the standard drug. This investigation supported the ethnomedicinal claims of S. anacardium.

Thermodynamic effects of replacements of Pro residues in helix interiors of maltose-binding protein.

Introduction of Pro residues into helix interiors results in protein destabilization. It is currently unclear if the converse substitution (i.e., replacement of Pro residues that naturally occur in helix interiors would be stabilizing). Maltose-binding protein is a large 370-amino acid protein that contains 21 Pro residues. Of these, three nonconserved residues (P48, P133, and P159) occur at helix interiors. Each of the residues was replaced with Ala and Ser. Stabilities were characterized by differential scanning calorimetry (DSC) as a function of pH and by isothermal urea denaturation studies as a function of temperature. The P48S and P48A mutants were found to be marginally more stable than the wild-type protein. In the pH range of 5-9, there is an average increase in T(m) values of P48A and P48S of 0.4 degrees C and 0.2 degrees C, respectively, relative to the wild-type protein. The other mutants are less stable than the wild type. Analysis of the effects of such Pro substitutions in MBP and in three other proteins studied to date suggests that substitutions are more likely to be stabilizing if the carbonyl group i-3 or i-4 to the mutation site is not hydrogen bonded in the wild-type protein.

Denaturant mediated unfolding of both native and molten globule states of maltose binding protein are accompanied by large deltaCp's.

Maltose binding protein (MBP) is a large, monomeric two domain protein containing 370 amino acids. In the absence of denaturant at neutral pH, the protein is in the native state, while at pH 3.0 it forms a molten globule. The molten globule lacks a tertiary circular dichroism signal but has secondary structure similar to that of the native state. The molten globule binds 8-anilino-1-naphthalene sulfonate (ANS). The unfolding thermodynamics of MBP at both pHs were measured by carrying out a series of isothermal urea melts at temperatures ranging from 274-329 K. At 298 K, values of deltaGdegrees , deltaCp, and Cm were 3.1+/-0.2 kcal mol(-1), 5.9+/-0.8 kcal mol(-1) K(-1) (15.9 cal (mol-residue)(-1) K(-1)), and 0.8 M, respectively, at pH 3.0 and 14.5+/-0.4 kcal mol(-1), 8.3+/-0.7 kcal mol(-1) K(-1) (22.4 kcal (mol-residue)(-1) K(-1)), and 3.3 M, respectively, at pH 7.1. Guanidine hydrochloride denaturation at pH 7.1 gave values of deltaGdegrees and deltaCp similar to those obtained with urea. The m values for denaturation are strongly temperature dependent, in contrast to what has been previously observed for small globular proteins. The value of deltaCp per mol-residue for the molten globule is comparable to corresponding values of deltaCp for the unfolding of typical globular proteins and suggests that it is a highly ordered structure, unlike molten globules of many small proteins. The value of deltaCp per mol-residue for the unfolding of the native state is among the highest currently known for any protein.