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Aim: The aim of study was to examine whether there exists significant difference in problem behavior among children with the variation in socioeconomic status in the family and parent child relationship (mother-child and father-child relationship). Study Design: A cross-sectional analytical study. Place and Duration of Study: Data collected in group (maximum with 20 participants by maintaining necessary Covid protocols) at schools in Kolkata with special appointment and after taking consent from the school authority and the participants in November, 2021. Methodology: 100 Bengali parents as participants from Kolkata with 30 to 45 years of age and having children within 10 years of age were included following necessary inclusion criteria. The tools used for the study were an information schedule, modified Kuppuswamy SES scale, the Child Behaviour Checklist and parent child relationship scale. Results: Results revealed that the problem behavior in children differed significantly due to the variation in socioeconomic status of the family and parent child relationship (in terms of mother child and father child relationship). Thus, the impact of socioeconomic status and parent child relationship on problem behavior among children is significant (P< .001). Conclusion: The present study concludes that there are significant impact of socioeconomic status and parent child relationship on problem behavior of the children. The present study has implications in emphasizing that socioeconomic status of the family and nature of parent child relationship play a pivotal role in generating internalizing and externalizing problem behaviors sometimes separately and sometimes together which gradually may turn into developing chronic psychological disturbances. Therefore, immediate measures should be taken to develop concern and to implement psychological intervention.

Energy transfer from light-harvesting ketocarotenoids to light-driven proton pumps xanthorhodopsins has been previously demonstrated in two unique cases: an extreme halophilic bacterium1 and a terrestrial cyanobacterium2. Attempts to find carotenoids that bind and transfer energy to rhodopsin proton pumps from the abundant marine and freshwater photoheterotrophs have thus far failed3–5. Here, using functional metagenomics combined with chromophore extraction from the environment, we detected light energy transfer from the widespread hydroxylated carotenoids zeaxanthin and lutein to the retinal moiety of xanthorhodopsins and proteorhodopsins. The light-harvesting carotenoids transfer up to 42% of the harvested energy in the violet/blue-light range to the green-light absorbing retinal chromophore. Our data suggest that these antennas have a significant impact on rhodopsin phototrophy in the world’s lakes, seas and oceans.

Due to their unique excited state dynamics, acenes play a dominant role in optoelectronic and light-harvesting applications. Their optical and electronic properties are typically tailored by side-group engineering, which often result in distortion of the acene core from planarity. However, the effect of such distortion on their excited state dynamics is not clear. In this work, we investigate the effect of twisting on the photophysics of acenes, which are helically locked to a defined twist angle by tethers of different lengths. Ultrafast transient absorption and time resolved fluorescence show a clear dependence of the rate of intersystem crossing with twisting. This trend is explained using quantum chemical calculations, showing an increase of spin-orbit coupling (SOC). At much earlier times, structural reorganization in S

In π-conjugated macrocycles, there is a trade-off between the global and local expression of effects such as aromaticity, with the outcome of the trade-off determined by the geometry and aromaticity of the constituent units. Compared with other aromatic rings, the aromatic character of furan is relatively small, and therefore global effects in macrocyclic furans are expected to be more pronounced. Following our introduction of macrocyclic oligofuran, we present the first synthesis of a series of π-conjugated bifuran macrocycles of various ring sizes, from trimer to hexamer, and characterize them using both computational and experimental methods. The properties of macrocyclic oligofurans change considerably with size: The smaller trimer is rigid, weakly emissive and planar as revealed by its single crystal structure, and displays global antiaromaticity. In contrast, the larger pentamer and hexamer are flexible, emissive, have non-planar structures, and exhibit local aromaticity. The results are supported by NICS and ACID calculations that indicate the global antiaromaticity of planar furan macrocycles, and by transient absorption measurements showing sharp absorption band for the trimer and only the internal conversion decay pathway.

Despite decades of investigation, mechanistic details of aqueous permanganate photo-decomposition remain unclear. Here we follow photoinduced dynamics of aqueous permanganate with femtosecond spectroscopy. Photoexcitation of KMnO4(aq) in the visible unleashes a sub-picosecond cascade of non-radiative transitions, leading to a distinct species which relaxes to S0 with a lifetime of 16 ps. Tuning excitation to the UV shows increasing formation of a metastable intermediate, which outlives our ∼1 ns window of detection. Guided by electronic structure calculations and observations from three pulse excitation experiments, we assign the 16 ps species as the lowest Jahn–Teller component of the 3T1 triplet state and suggest a plausible sequence of radiationless transitions, which rapidly populate it. In conjunction with photodecomposition quantum yields obtained from the literature, these results demonstrate that aqueous permanganate photo-decomposition proceeds through a long-lived intermediate which is formed in parallel to the triplet in less than one ps upon UV absorption. The possibility that this is the postulated highly oxidative peroxo species, a fraction of which leads to the stable (MnO2− + O2) fragments, is discussed. Finally, periodic modulations detected in the pump–probe signal are assigned to ground-state vibrational coherences excited by impulsive Raman. Their wavelength-dependent absolute phases outline the borders between adjacent electronic transitions in the linear spectrum of permanganate.

Organic π-conjugated compounds showing polymorphic and mechanofluorochromic (MFC) behaviors are promising candidates for many potential applications in materials chemistry. Herein, we report two distinct molecular designs based on phenothiazine as a donor and triarylborane and cyanostilbene as acceptors, for example, an acceptor–donor–acceptor system (A–D–A; compound 3) and donor–acceptor (D–A; compound 4) moieties, in which 3 exhibits polymorphism with two distinct emissions (yellow and red). The single crystal X-ray diffraction analyses of 3 clearly show two conformational isomers. The color of the emission can be altered by a grinding or fuming process.

The present study investigates the photophysical properties of two highly conjugated pyrene and anthracene derivatives viz ( E )-4-(2-(pyren-1-yl) vinyl) benzonitrile (PyCN) and ( E )-4-(2-(anthracen-9-yl) vinyl) benzonitrile (AnCN) in the presence and absence of electron donors such as N , N -diethylaniline (DEA) and N , N -diphenylamine (DPA). The observed rates of back electron transfer (BET) in the case of PyCN-DEA and AnCN-DEA are 1.3 × 10 5 and 4.8 × 10 4 s −1 , respectively, which are 3–4 orders of magnitude lower compared to the well-known pyrene–amine and anthracene–amine systems. Mechanistic investigations indicate that the donor-acceptor systems undergo different pathways in presence of tertiary and the secondary amine. The results indicate that the design strategy is highly efficient in reducing the rate of back electron transfer, which results in long lived charge-separated excited states.

The aim of the study was to determine whether the general intelligence, cognitive processes, school achievement, and intelligence-achievement relationship of adolescents with subclinical levels of obsessive-compulsive symptoms differed from those of their normal counterparts. From an initial large pool of 14-year-old Bengali students in eighth grade, 110 girls and 100 boys were finally selected. The Children's Yale-Brown Obsessive Compulsive Scale and the Children's Obsessional Compulsive Inventory were used to exclude those with clinical levels of obsessive-compulsive disorder, and to identify those with subclinical levels of obsessive-compulsive symptoms as differentiated from the typically developed adolescents. The participants were administered the Standard Progressive Matrices for assessing general intelligence and Sumon's Attention Memory Module to assess memory-related variables and span of attention. School achievement was assessed from school records from the last two years. Intelligence-achieve...

Designing intramolecular charge-transfer (ICT)-based luminogenic ordered assemblies exhibiting significant electrical transport is a challenging task in the field of organic optoelectronics. In this context, a series of novel phenothiazine-based oligo(p-phenylenevinylene) (OPV1-6) derivatives were designed and their structure-property relationship was investigated. Upon examining their photophysical properties, all the OPVs were found to exhibit significant intramolecular charge-transfer characteristics in organic solvents. While inspecting the self-assembly behaviour, the OPV with a long alkyl chain on the central phenyl core (OPV4) underwent gelation in organic solvent mixtures through strong hydrophobic interactions of the long hexadecyl chains and π-interactions from their aromatic counterparts. Computational studies revealed a lamellar packing of molecules in the assembly. Interestingly, the degree of ICT and the gelation abilities of OPVs were significantly influenced by the electronic nature of the substituents appended to the peripheral phenothiazines. Further, the AC impedance results revealed an increase in storage and electronic transport for the fluorescent thin films prepared by an increase in the content of OPV4 in PMMA.

Organic materials generating pure white light emission have attracted considerable attention in recent times due to their potential applications in lighting and display devices. We have used anthracene carboxylic acid (AnA) and anthracene carbaldehyde (AnC) to generate white light using solvent induced selective self-assembly (SISSA). Mechanistically, SISSA prevents a fast intersystem crossing of the AnC monomer and generates an emissive state from the self-assembled AnC. While AnA emits in the blue region, the self-assembled AnC emits in the greenish yellow region with identical emission intensity. CIE coordinates (0.33, 0.33) of pure white light have been achieved by incorporating orange emitting rhodamine B. More importantly, the pure white light formation has been demonstrated at desired temperatures in both aqueous medium as well as in an agar–agar hydrogel.

Self-assembly of AB2 and AB3 type low molecular weight poly(aryl ether) dendrons that contain hydrazide units were used to investigate mechanistic aspects of helical structure formation during self-assembly. The results suggest that there are three important aspects that control helical structure formation in such systems with acyl hydrazide/hydrazone linkage: i) J-type aggregation, ii) the hydrogen-bond donor/acceptor ability of the solvent, and iii) the dielectric constant of the solvent. The monomer units self-assemble to form dimer structures through hydrogen-bonding and further assembly of the hydrogen-bonded dimers leads to macroscopic chirality in the present case. Dimer formation was confirmed by NMR spectroscopy and by mass spectrometry. The self-assembly in the system was driven by hydrogen-bonding and ?-? stacking interactions. The morphology of the aggregates formed was examined by scanning electron microscopy, and the analysis suggests that aprotic solvent systems facilitate helical fibre formation, whereas introduction of protic solvents results in the formation of flat ribbons. This detailed mechanistic study suggests that the self-assembly follows a nucleation-elongation model to form helical structures, rather than the isodesmic model. � 2015 Wiley-VCH Verlag GmbH & Co. KGaA.