Suppression of the rate of growth of dynamic heterogeneities and its relation to the local structure in a supercooled polydisperse liquid

The relationship between the microscopic arrangement of molecules in a supercooled liquid and its slow dynamics at low temperature near glass transition is studied by molecular dynamics simulations. A Lennard-Jones liquid with polydispersity in size and mass of constituent particles is chosen as the model system. Our studies reveal that the local structure (that varies with polydispersity) plays a crucial role both in the slowing down of dynamics and in the growth of the dynamic heterogeneities, besides determining the glass forming ability of the system. Increasing polydispersity at fixed volume fraction is found to suppress the rate of growth of dynamic correlations, as detected by the growth in the peak of the nonlinear density response function, χ4(t). The growth in dynamical correlation is manifested in a stronger than usual breakdown of Stokes-Einstein relation at lower polydispersity at low temperatures and also leads to a decrease in the fragility of the system with polydispersity. We show that the suppression of the rate of growth of the dynamic heterogeneity can be attributed to the loss of structural correlations (as measured by the structure factor and the local bond orientational order) with polydispersity. While a critical polydispersity is required to avoid crystallization, we find that a further increase in polydispersity lowers the glass forming ability

Vibrational dynamics and boson peak in a supercooled polydisperse liquid

Vibrational density of states (VDOS) in a supercooled polydisperse liquid is computed by diagonalizing the Hessian matrix evaluated at the potential energy minima for systems with different values of polydispersity. An increase of polydispersity leads to an increase in relative population of the localized high-frequency modes. At low frequencies, the density of states show an excess compared to the Debye squared-frequency law, which has been identified with the boson peak. The height of the boson peak increases with polydispersity. The values of the participation ratio as well as the level spacing statistics demonstrate that the modes comprising the boson peak are largely delocalized. Interestingly, the intensity of the boson peak shows a rather narrow sensitivity to changes in temperature and is seen to persist even at high temperatures. Study of the difference spectrum at two different polydispersity reveals that the increase in the height of boson peak is due to a population shift from modes with frequencies above the maximum in the VDOS to that below the maximum, indicating an increase in the fraction of the unstable modes in the system. The latter is further supported by the facilitation of the observed dynamics by polydispersity. Since the strength of the liquid increases with polydispersity, the present result provides an evidence that the intensity of boson peak correlates positively with the strength of the liquid, as observed earlier in many experimental systems

The Impact of Screen Time and Mobile Dependency on Cognition, Socialization and Behaviour Among Early Childhood Students During the Covid Pandemic- Perception of the Parents

Digital technology systems are adopted rapidly throughout the globe for the virtual learning process especially with the outbreak of the Covid-19 pandemic. Digital screen-based gadgets are integrated to provide a seamless interactive medium of learning even before the initiation of formal education. Studies on the technology use of younger children are critical as uncontrolled gadget use affects their developmental stages yet these studies are still in the infancy stage. This study analyses the psychoeducational impact of extended use of digital gadgets and mobile dependency on early childhood manifested through their cognition, socialization and behaviour. This descriptive study is based on the random responses of 511 parents about their young children of 3-6 years distributed at five civil districts of Kerala State. From the analysis, it is found that the extended use of digital gadgets influenced young children’s mobile dependency, socialization process, cognition and behaviour patterns. The young children exhibited alienation tendencies and behavioural deviations which are correlated to their screen time. Both male and female reported similar results.  Significant differences were observed with respect to the age of the children and their parental characteristics. Their mobile dependency mediated their extended digital Screen Time to the Behaviour. Significant relation was predicted by extended Screen Time on Behaviour of the students with a partial sequential path through mobile Dependency, Cognition and Socialization. The study shed light on the urgency of parental care and implementation of a balanced gadget usage system to reduce the detrimental impacts of psychoeducational factors

Energy Landscape, Anti-Plasticization and Polydispersity Induced Crossover of Heterogeneity in Supercooled Polydisperse Liquids

Polydispersity is found to have a significant effect on the potential energy landscape; the the average inherent structure energy with temperature decreases with polydispersity. Increasing polydispersity at fixed volume fraction decreases the glass transition temperature and the fragility of glass formation analogous to the antiplasticization seen in some polymeric melts. An interesting temperature dependent crossover of heterogeneity with polydispersity is observed at low temperature due to the faster build-up of dynamic heterogeneity at lower polydispersity.Comment: 17 pages, 4 figures (Submitted to Phys. Rev. Lett.

Disease-modifying therapies alter gut microbial composition in MS.

Objective:To determine the effects of the disease-modifying therapies, glatiramer acetate (GA) and dimethyl fumarate (DMF), on the gut microbiota in patients with MS. Methods:Participants with relapsing MS who were either treatment-naive or treated with GA or DMF were recruited. Peripheral blood mononuclear cells were immunophenotyped. Bacterial DNA was extracted from stool, and amplicons targeting the V4 region of the bacterial/archaeal 16S rRNA gene were sequenced (Illumina MiSeq). Raw reads were clustered into Operational Taxonomic Units using the GreenGenes database. Differential abundance analysis was performed using linear discriminant analysis effect size. Phylogenetic investigation of communities by reconstruction of unobserved states was used to investigate changes to functional pathways resulting from differential taxon abundance. Results:One hundred sixty-eight participants were included (treatment-naive n = 75, DMF n = 33, and GA n = 60). Disease-modifying therapies were associated with changes in the fecal microbiota composition. Both therapies were associated with decreased relative abundance of the Lachnospiraceae and Veillonellaceae families. In addition, DMF was associated with decreased relative abundance of the phyla Firmicutes and Fusobacteria and the order Clostridiales and an increase in the phylum Bacteroidetes. Despite the different changes in bacterial taxa, there was an overlap between functional pathways affected by both therapies. Interpretation:Administration of GA or DMF is associated with differences in gut microbial composition in patients with MS. Because those changes affect critical metabolic pathways, we hypothesize that our findings may highlight mechanisms of pathophysiology and potential therapeutic intervention requiring further investigation

Future Ambulance

In March 2014, the Digital Health & Care Institute (DHI) Experience Labs collaborated with the Scottish Ambulance Service (SAS) to prototype what the ambulance of the future could be like. The ‘Future Ambulance’ project was informed by prior research carried out by the Glasgow School of Art, and utilised a ‘3-Cubed’ methodology, in which participants collaborated in small groups consisting of two designers paired with an SAS paramedic. Eleven ambulance crew members of different levels of seniority and experience, from both rural and urban regions, took part in the Experience Labs, which were held in the Alexander Graham Bell Centre for Life Sciences at Moray College UHI in Elgin. Four spaces were created: Studio (group activities); Control (video monitoring, observation and recording); and Interview Rooms (individual interviews and focus group activity). The Experience Labs included three elements: acting out real-life scenarios provided by the ambulance crews; group discussion; and semi-structured interviews. The outputs included photographs; film; and graphical and written outputs, which were analysed for emerging themes and findings

MRI Analysis of White Matter Myelin Water Content in Multiple Sclerosis: A Novel Approach Applied to Finding Correlates of Cortical Thinning

A novel lesion-mask free method based on a gamma mixture model was applied to myelin water fraction (MWF) maps to estimate the association between cortical thickness and myelin content, and how it differs between relapsing-remitting (RRMS) and secondary-progressive multiple sclerosis (SPMS) groups (135 and 23 patients, respectively). It was compared to an approach based on lesion masks. The gamma mixture distribution of whole brain, white matter (WM) MWF was characterized with three variables: the mode (most frequent value) m1 of the gamma component shown to relate to lesion, the mode m2 of the component shown to be associated with normal appearing (NA) WM, and the mixing ratio (λ) between the two distributions. The lesion-mask approach relied on the mean MWF within lesion and within NAWM. A multivariate regression analysis was carried out to find the best predictors of cortical thickness for each group and for each approach. The gamma-mixture method was shown to outperform the lesion-mask approach in terms of adjusted R2, both for the RRMS and SPMS groups. The predictors of the final gamma-mixture models were found to be m1 (β = 1.56, p \u3c 0.005), λ (β = −0.30, p \u3c 0.0005) and age (β = −0.0031, p \u3c 0.005) for the RRMS group (adjusted R2 = 0.16), and m2 (β = 4.72, p \u3c 0.0005) for the SPMS group (adjusted R2 = 0.45). Further, a DICE coefficient analysis demonstrated that the lesion mask had more overlap to an ROI associated with m1, than to an ROI associated with m2 (p \u3c 0.00001), and vice versa for the NAWM mask (p \u3c 0.00001). These results suggest that during the relapsing phase, focal WM damage is associated with cortical thinning, yet in SPMS patients, global WM deterioration has a much stronger influence on secondary degeneration. Through these findings, we demonstrate the potential contribution of myelin loss on neuronal degeneration at different disease stages and the usefulness of our statistical reduction technique which is not affected by the typical bias associated with approaches based on lesion masks

Sinapis arvensis-Wild Mustard as an Anti-inflammatory Agent: An In-vitro Study

Introduction: Inflammation is body’s immune response to harmful stimulus. Commonly used conventional anti-inflammatory agents are Non-Steroidal Anti-inflammatory Drugs (NSAIDs). But on prolonged long-term use, it causes serious adverse events. So, the search towards natural agents which have anti-inflammatory property are increasing nowadays. Sinapis arvensis is an annual flowering plant which has proven multipurpose medicinal phytoconstituents. Aim: To evaluate in-vitro anti-inflammatory effects of flower extracts of Sinapis arvensis with diclofenac as standard. Materials and Methods: This in-vitro study assessed the laboratory based anti-inflammatory activity, performed using Bovine Serum Albumin (BSA) assay in December 2021 at Sree Balaji Medical College and Hospital, Chennai, Tamil Nadu, India. BSA at pH of 6.8 generated denatured proteins. The anti-inflammatory activity of the sample (flower extracts of Sinapis arvensis) and standard (Diclofenac) was assessed by adding to BSA and percentage of inhibition of denaturation were calculated using the formula based on the absorbance measured. Descriptive statistics was used for analysis of collected data. Results: The concentration-dependent inhibition of protein denaturation was observed for both Sinapis arvensis and Diclofenac. At 100 μg concentration, percentage of inhibition reached up to 81.8% and 100% for Sinapis arvensis and Diclofenac, respectively. Conclusion: The present study showed that flower extracts of Sinapis arvensis exhibited concentration dependent anti-inflammatory property invitro which proves to be nearly equivalent with that of the standard Diclofenac

Supervillin Binding to Myosin II and Synergism with Anillin Are Required for Cytokinesis

Cytokinesis, the process in which cytoplasm is apportioned between dividing daughter cells, requires coordination of myosin II function, membrane trafficking and central spindle organization. Most known regulators act during late cytokinesis; a few, including the myosin II-binding proteins anillin and supervillin, act earlier. Anillin\u27s role in scaffolding the membrane cortex with the central spindle is well established, but the mechanism of supervillin action is relatively uncharacterized. We show here that two regions within supervillin affect cell division: residues 831-1281, which bind central spindle proteins, and residues 1-170, which bind the myosin II heavy chain (MHC) and the long form of myosin light chain kinase (l-MLCK). MHC binding is required to rescue supervillin deficiency, and mutagenesis of this site creates a dominant-negative phenotype. Supervillin concentrates activated and total myosin II at the furrow, and simultaneous knockdown of supervillin and anillin additively increase cell division failure. Knockdown of either protein causes mislocalization of the other, and endogenous anillin increases upon supervillin knockdown. Proteomic identification of interaction partners recovered using a high-affinity GFP nanobody suggest that supervillin and anillin regulate the myosin II- and actin cortical cytoskeletons through separate pathways. We conclude that supervillin and anillin play complementary roles during vertebrate cytokinesis

Agricultural and empowerment pathways from land ownership to women's nutrition in India.

Land size is an important equity concern for the design of 'nutrition-sensitive' agricultural interventions. We unpack some of the pathways between land and nutrition using a cross-sectional baseline survey data set of 4,480 women from 148 clusters from the 'Upscaling Participatory Action and Videos for Agriculture and Nutrition' trial in Keonjhar district in Odisha, India. Variables used are household ln-land size owned (exposure) and maternal dietary diversity score out of 10 food groups and body mass index (BMI; kg/m2 ) (outcomes); and mediators investigated are production diversity score, value of agricultural production, and indicators for women's empowerment (decision-making in agriculture, group participation, work-free time and land ownership). We assessed mediation using a non-parametric potential outcomes framework method. Land size positively affects maternal dietary diversity scores [β 0.047; 95% confidence interval (CI) (0.011, 0.082)] but not BMI. Production diversity, but not value of production, accounts for 17.6% of total effect mediated. We observe suppression of the effect of land size on BMI, with no evidence of a direct effect for either of the agricultural mediators but indirect effects of β -0.031 [95% CI (-0.048, -0.017)] through production diversity and β -0.047 [95% CI (-0.075, -0.021)] through value of production. An increase in land size positively affects women's decision-making, which in turn negatively affects maternal BMI. The positive effect of work-free time on maternal BMI is suppressed by the negative effect of household land size on work-free time. Agriculture interventions must consider land quality, women's decision-making and implications for women's workload in their design