Photo-inhibition Effect from Strong Electron Withdrawing Nitro Group in N-[(E)(4-Bromophenyl)Methylidene]-4 Nitroaniline

Light induced effect of N-[(E)-(4-bromophenyl)methylidene]-4nitroaniline was investigated using UV-Vis spectrophotometer. This study revealed that the presence of strong electron withdrawing nitro group inhibited the photo-reactivity of the compound. Mainly, molecular structure and functional groups have tremendous influence on chromophoric compounds. The photoisomerization effect was not found in this compound, due to the photo-inhibition of nitro group present in the molecular system

Emotion classification in Parkinson's disease by higher-order spectra and power spectrum features using EEG signals: A comparative study

Deficits in the ability to process emotions characterize several neuropsychiatric disorders and are traits of Parkinson's disease (PD), and there is need for a method of quantifying emotion, which is currently performed by clinical diagnosis. Electroencephalogram (EEG) signals, being an activity of central nervous system (CNS), can reflect the underlying true emotional state of a person. This study applied machine-learning algorithms to categorize EEG emotional states in PD patients that would classify six basic emotions (happiness and sadness, fear, anger, surprise and disgust) in comparison with healthy controls (HC). Emotional EEG data were recorded from 20 PD patients and 20 healthy age-, education level- and sex-matched controls using multimodal (audio-visual) stimuli. The use of nonlinear features motivated by the higher-order spectra (HOS) has been reported to be a promising approach to classify the emotional states. In this work, we made the comparative study of the performance of k-nearest neighbor (kNN) and support vector machine (SVM) classifiers using the features derived from HOS and from the power spectrum. Analysis of variance (ANOVA) showed that power spectrum and HOS based features were statistically significant among the six emotional states (p < 0.0001). Classification results shows that using the selected HOS based features instead of power spectrum based features provided comparatively better accuracy for all the six classes with an overall accuracy of 70.10% ± 2.83% and 77.29% ± 1.73% for PD patients and HC in beta (13-30 Hz) band using SVM classifier. Besides, PD patients achieved less accuracy in the processing of negative emotions (sadness, fear, anger and disgust) than in processing of positive emotions (happiness, surprise) compared with HC. These results demonstrate the effectiveness of applying machine learning techniques to the classification of emotional states in PD patients in a user independent manner using EEG signals. The accuracy of the system can be improved by investigating the other HOS based features. This study might lead to a practical system for noninvasive assessment of the emotional impairments associated with neurological disorders

Crystal structure of methyl 1-methyl-2-oxospiro[indoline-3,2′-oxirane]-3′-carboxylate

Acknowledgements The authors thank Dr Babu Vargheese, SAIF, IIT, Madras, India, for the data collection.Peer reviewedPublisher PD

Synthesis of New Liquid Crystals Embedded Gold Nanoparticles for Photoswitching Properties

A new series of liquid crystals decorated gold nanoparticles is synthesized whose molecular architecture has azobenzenes moieties as the peripheral units connected to gold nanoparticles (Au NPs) via alkyl groups. The morphology and mesomorphic properties were investigated by field emission scanning electron microscope, high-resolution transmission electron microscopy, differential scanning calorimetry and polarizing optical microscopy. The thiolated ligand molecules (3a–c) showed enantiotropic smectic A phase, whereas gold nanoparticles (5a–c) exhibit nematic and smectic A phase with monotropic nature. HR-TEM measurement showed that the functionalized Au NPs are of the average size of 2 nm and they are well dispersed without any aggregation. The trans-form of azo compounds showed a strong band in the UV region at ∼378 nm for the π-π∗ transition, and a weak band in the visible region at ∼472 nm due to the n-π∗ transition. These molecules exhibit attractive photoisomerization behaviour in which trans-cis transition takes about 15 s whereas the cis-trans transition requires about 45 min for compound 5c. The extent of reversible isomerization did not decay after 10 cycles, which proved that the photo-responsive properties of 5c were stable and repeatable. Therefore, these materials may be suitably exploited in the field of molecular switches and the optical storage devices

Synthesis and liquid crystalline behaviour of substituted (E)-phenyl-4-(phenyldiazenyl) benzoate derivatives and their photo switching ability

Azobenzene derivatives containing phenyl/4-halogen-phenyl 4-{(E)-[4-(pent-4-en-1-yloxy)phenyl] diazenyl}benzoate group with different electronegative substituent (H, F, Cl, Br and I) at other end was synthesised. These azo-based benzoate derivatives have been characterised by FTIR, 1H-NMR, 13C-NMR, elemental analyser, POM and UV-Vis spectroscopy. Photosaturation at 358 nm obtained after 82 s of UV irradiation and the longest thermal back relaxation time of 45 h recorded by UVVis. The azo derivative could be possible photolock under UV light, as observed by the improved thermal back relaxation time. The resulting photolockable chain of azobenzene might prove valuable in the development of optical device application. These azobenzene moieties also exhibit liquid crystalline behaviour with respect to the halogen substitution as an electron withdrawing group shows that strong structure property relationship exists among them

Ethyl 4-(4-bromo­phen­yl)-6-r-phenyl-2-oxocyclo­hex-3-ene-1-t-carboxyl­ate

In the title compound, C21H19BrO3, the cyclo­hexene ring adopts an envelope conformation, with all substituents equatorial. The plane through its five coplanar atoms makes dihedral angles of 28.88 (10) and 71.94 (10)° with the bromo­benzene and phenyl rings, respectively. The dihedral angle between the latter two rings is 51.49 (15)°. Inter­molecular C—H⋯O hydrogen bonds are found in the crystal structure; a C—H⋯π inter­action is also present

The Effect of Lateralization of Motor Onset and Emotional Recognition in PD Patients Using EEG

The objective of this research was to investigate the relationship between emotion recognition and lateralization of motor onset in Parkinson’s disease (PD) patients using electroencephalogram (EEG) signals. The subject pool consisted of twenty PD patients [ten with predominantly leftsided (LPD) and ten with predominantly rightsided (RPD) motor symptoms] and 20 healthy controls (HC) that were matched for age and gender. Multimodal stimuli were used to evoke simple emotions, such as happiness, sadness, fear, anger, surprise, and disgust. Artifactfree emotion EEG signals were processed using the auto regressive spectral method and then subjected to repeated ANOVA measures. No group differences were observed across behavioral measures? however, a significant reduction in EEG spectral power was observed at alpha, beta and gamma frequency oscillations in LPD, compared to RPD and HC participants, suggesting that LPD patients (inferred righthemisphere pathology) are impaired compared to RPD patients in emotional processing. We also found that PD related emotional processing deficits may be selective to the perception of negative emotions. Previous findings have suggested a hemispheric effect on emotion processing that could be related to emotional response impairment in a subgroup of PD patients. This study may help in clinical practice to uncover potential neurophysiologic abnormalities of emotional changes with respect to PD patient’s motor onset

3′-[Hy­droxy(4-oxo-4H-chromen-3-yl)meth­yl]-2-oxospiro­[indoline-3,2′-pyrrolidine]-3′-carbonitrile

In the title compound, C23H19N3O4, the pyran ring adopts a half-chair conformation, while the pyrrolidine (with a C atom as the flap atom) and the five-membered ring in the indoline (with a C atom as the flap atom) ring system adopt slight envelope conformations. The pyrrolidine ring makes dihedral angles of 83.3 (1) and 60.4 (1)° with the mean plane through all non-H atoms of the indoline and chromene ring systems, respectively. In the crystal, mol­ecules are connected by two unique N—H⋯O and O—H⋯O hydrogen-bonding inter­actions, which form centrosymmetric patterns described by graph-set motifs R 2 2(18) and R 2 2(14). These two motifs combine to form a hydrogen-bonded chain which propagates in the a-axis direction. The crystal structure is also stablized by C—H⋯O inter­actions and by aromatic π–π stacking inter­actions between the pyran and benzene rings of neighbouring mol­ecules [centroid–centroid distance = 3.755 (1) Å and slippage = 1.371 (2) Å]