Role of living conditions and socioenvironmental factors on chronotype in adolescents

An individual's chronotype, defined as the preference for rest and activity at different times of the day, is linked to several physiological and psychological outcomes. Research on environmental determinants of chronotype has focussed mostly on geographic location, whereas other socioenvironmental determinants have been neglected. We aimed to investigate the association between other previously unrecognized socioenvironmental factors and chronotypes in adolescents. We analysed data of 1916 Bengali adolescents (aged between 13-14 years, 47% girls). Chronotype was determined by the reduced morningness-eveningness questionnaire (rMEQ), and socioenvironmental factors were identified through a structured questionnaire. Associations were analysed using multinomial logistic regression models. Our findings demonstrated that living in urban areas, the presence of a smoker at home, and higher parental education were associated with a higher evening activity (eveningness), while the use of biomass cooking media (compared to liquefied petroleum gas) and assisting parents in farming were associated with higher morningness in adolescents. This is the first study to identify the association between previously unrecognized socioenvironmental factors and chronotypes delineating the interaction between environment and sleep in adolescents and might help the parents to understand the importance of a proper sleep-activity rhythm of their kids through a comprehensive understanding of their surrounding environment and other factors

Chronotype assessment of the Bengalese adolescents: an observational study using a Bengali version of the reduced Morningness-Eveningness Questionnaire (rMEQ)

Chronotype or morningness orientation is an interpersonal characteristic that influence human physiology and psychology and less is known about the chronotype of the Bengalese adolescents in India. We aimed to study the chronotype of this population by using a translated version of a previously established questionnaire. 471 Bengali-speaking adolescents (13–14 years) (boys = 268, girls = 203) of West Bengal, India were included in this study and their chronotype was assessed using an interviewer-administered Bengali version of the reduced Morningness–eveningness Questionnaire (rMEQ). The reliability of the translated instrument was assessed using Cronbach’s α. Chi-squared test was used to observe the chronotype distribution between the boys and girls. rMEQ scores of all the participants ranged between 5 and 25 with a median value of 17 (25–75th percentile: 15–20). Cronbach’s α was 0.751. Using cut off scores, we found 47% of our study participants were of morning chronotype, whereas the intermediate and evening types were of 50% and 3%, respectively. Chi-squared test demonstrated a significantly higher morningness among boys than the girls. The study describes the morningness orientation pattern of the Bengalese adolescents that may have some defined influence on their physiological and psychological characteristics including health and disease.This study was partially supported by the unrestricted internal research grant of the Allergy & Asthma Research Centre, Kolkat

Defined tetra-allelic gene disruption of the 4-coumarate:coenzyme A ligase 1 (Pv4CL1) gene by CRISPR/Cas9 in switchgrass results in lignin reduction and improved sugar release

Abstract Background The development of genome editing technologies offers new prospects in improving bioenergy crops like switchgrass (Panicum virgatum). Switchgrass is an outcrossing species with an allotetraploid genome (2n = 4x = 36), a complexity which forms an impediment to generating homozygous knock-out plants. Lignin, a major component of the plant cell wall and a contributor to cellulosic feedstock’s recalcitrance to decomposition, stands as a barrier to efficient biofuel production by limiting enzyme access to cell wall polymers during the fermentation process. Results We developed a CRISPR/Cas9 genome editing system in switchgrass to target a key enzyme involved in the early steps of monolignol biosynthesis, 4-Coumarate:coenzyme A ligase (4CL). Three 4CL genes, Pv4CL1, Pv4CL2, and Pv4CL3, were identified in switchgrass. Expression analysis revealed that Pv4CL1 transcripts were more abundant in the stem than in the leaf, while Pv4CL2 transcripts were barely detectable and Pv4CL3 was mainly expressed in the leaf. Pv4CL1 was selected as the target for CRISPR/Cas9 editing because of its preferential expression in highly lignified stem tissues. Specific guide RNA was constructed to target Pv4CL1. After introducing the construct into switchgrass calli, 39 transgenic plants were regenerated. Using two rounds of PCR screening and sequencing, four plants were confirmed to have tetra-allelic mutations simultaneously. The Pv4CL1 knock-out plants had reduced cell wall thickness, an 8–30% reduction in total lignin content, a 7–11% increase in glucose release, and a 23–32% increase in xylose release. Conclusion This study established a successful CRISPR/Cas9 system in switchgrass with mutation efficiency reaching 10%. The system allows the precise targeting of the selected Pv4CL1 gene to create switchgrass knock-out mutant plants with decreased lignin content and reduced recalcitrance

Thermodynamically stable octahedral MoS2 in van der Waals hetero-bilayers

Reversible switching of the structural ground state of a solid is a fundamental goal in materials engineering, which has not been achieved in atomically thin layers of van der Waals crystals. This is particularly important for the transition metal dichalcogenides, such as molybdenum disulphide (MoS2), where the higher-energy octahedral polymorphs exhibit a wide range of fascinating properties. Here we show that thermodynamically stable octahedral phase of monolayer MoS2 can be achieved in coexistence with the 1H phase, at temperatures below similar to 500 K, by forming a van der Waals hybrid with another layered solid, such as hexagonal boron nitride (hBN) or graphene. Spatial mapping and temperature-dependence of the zone-folded Raman modes reveal that the octahedral phase exists only within the heterostructure region, and exhibits remarkable stability to repeated thermal cycling. A concurrent shift in the out-of-plane A1(g) vibrational mode of MoS2, and near-absence of the octahedral phase in homo-epitaxial structures, suggest likely role of local lattice relaxation due to incommensurability-driven stress fields. Our experiment establishes van der Waals hetero-epitaxy as a new tool for crystal structure engineering in atomic membranes

Prevalence and risk factors of asthma and allergy-related diseases among adolescents (PERFORMANCE) study: rationale and methods

Despite a considerable number of international reports on allergic diseases among children, information about the prevalence and risk factors of asthma and allergy-related diseases among Indian adolescents is relatively sparse. The Prevalence and Risk Factors of Asthma and Allergy-Related Diseases among Adolescents (PERFORMANCE) study has been conceived to study the aetiology of asthma and allergic diseases including rhinoconjunctivitis, atopic eczema and food allergies among adolescents in West Bengal, India, using standardised methods and collaborations. The aims of the study are: 1) to estimate the prevalence and risk factors of asthma and allergic diseases among the adolescents residing in rural, suburban and urban areas of West Bengal; 2) to obtain information about the possible role of lifestyle factors (smoking, diet and physical activity) on the disease prevalence; and 3) to create a network for further investigation on social, environmental and genetic factors affecting the diseases. The PERFORMANCE study comprises two phases. The phase I study will investigate the prevalence and possible contributing factors of asthma and allergic diseases in a defined population. The phase II study will be performed as a follow-up of phase I to assess the incidence of asthma and allergic diseases