Ferroelectric Nematic Droplets in their Isotropic Melt

The isotropic to ferroelectric nematic liquid transition had been theoretically studied over one hundred years ago, but its experimental studies are rare. Here we present polarizing optical microscopy studies and theoretical considerations of ferroelectric nematic liquid crystal droplets coexisting with the isotropic melt. We find that the droplets have flat pancake-like shapes that are thinner than the sample thickness as long as there is a room to increase the lateral droplet size. In the center of the droplets a wing shaped defect with low birefringence is present that moves perpendicular to a weak in-plane electric field, and then extends and splits in two at higher fields. Parallel to the defect motion and extension, the entire droplet drifts along the electric field with speed that is independent of the size of the droplet and is proportional to the amplitude of the electric field. After the field is increased above 1V/mm the entire droplet gets deformed and oscillates with the field. These observations led us to determine the polarization field and revealed the presence of a pair of positive and negative bound electric charge due to divergences of polarization around the defect volume

Unmasking a potential crisis: an exploration of gaming addiction and depression in adolescents and young adults through a cross-sectional survey

Introduction: Gaming disorder is defined as a pattern of gaming behaviour characterised by impaired control over gaming, prioritisation of gaming over other activities to the point where gaming takes precedence over other interests and daily activities, and persistence or escalation of gaming despite negative consequences. Given the increasing global interest in videogames, particularly among adolescents and young adults, this study investigated the prevalence of gaming disorder and its associated factors among Sri Lankan adolescents and young adults, with a focus on factors associated with gaming addiction. Materials and Methods: A cross-sectional survey was conducted involving 401 Sri Lankan adolescents and young adults who played video games, through an anonymous online survey using snowball sampling. The survey comprised four sections: demographic data, influencing factors for game playing, the seven-item Game Addiction Scale and a validated depression scale (nine-item Patient Health Questionnaire). SPSS IBM (version 27) was used for data analysis, which includes means, standard deviations, frequencies, percentages, Pearson’s correlation and chi-square tests. Results: A total of 401 gamers participated, comprising adolescents (10-18 years; 9.5%) and young adults (19-35 years; 90.5%). The majority were non-gaming addicts (71.57%), and among the gaming addicts, 8.48% were classified as monothetic gaming addicts, while 19.5% were classified polythetic gaming addicts. Slightly more males were game addicts (52.63%) than females. There was a low positive correlation between videogame addiction and depression (r=0.321). More than half of the sample believed that visual triggers (58.6%) and frequent reward systems (56.1%) influenced their gameplay. There was a significant association (p <0.05) between gaming addiction and the three observed characteristics: visual triggers, audio triggers, and frequent rewards. Conclusions: Just under one-tenth of the study population sampled was classified as having a gaming addiction, with males having a slightly higher prevalence than females. The positive correlation between gaming disorder and depression suggests a consequential and potentially life-threatening outcome, wherein depression emerges as a serious consequence of addiction to gaming. When the structural characteristics of videogames, such as auditory, visual and frequent reward systems were considered, game addicts were more influenced by them

Low maternal education and socioeconomic status were associated with household food insecurity in children under five with diarrhoea in Bangladesh.

Household food insecurity (HFI) is insufficient access to nutritionally safe and adequate foods to meet the dietary needs for an active and healthy life. We examined the prevalence and determinants of HFI in Bangladeshi children under five with diarrhoea

Improving the Accuracy of Hydrodynamic Simulations in Data Scarce Environments Using Bayesian Model Averaging: A Case Study of the Inner Niger Delta, Mali, West Africa

In this paper, the study area was the Inner Niger Delta (IND) in Mali, West Africa. The IND is threatened by climate change, increasing irrigation, and dam operations. 2D hydrodynamic modelling was used to simulate water levels, discharge, and inundation extent in the IND. Three different digital elevation models (DEM) (SRTM, MERIT, and a DEM derived from satellite images were used as a source of elevation data. Six different models were created, with different sources of elevation data and different downstream boundary conditions. Given that the performance of the models varies according to the location in the IND, the variable under consideration and the performance criteria, Bayesian Model Averaging (BMA) was used to assess the relative performance of each of the six models. The BMA weights, along with deterministic performance measures, such as the Nash Sutcliffe coefficient (NS) and the Pearson’s correlation coefficient (r), provide quantitative evidence as to which model is the best when simulating a particular hydraulic variable at a particular location. After the models were combined with BMA, both discharge and water levels could be simulated with reasonable precision (NS > 0.8). The results of this work can contribute to the more efficient management of water resources in the IND

Comparative analysis of proximate compositions, mineral and functional chemical groups of 15 different seaweed species

Seaweed is a popular edible source and is associated with many foods and pharmaceutical industries around the world. The current research aims to provide information on the chemical composition of 15 seaweed species consisted of Chlorophyta, Ochrophyta/Phaeophyceae, and Rhodophyta macroalgae, collected from coastal areas of Sri Lanka. Seaweed samples were subjected to the analysis of lipids, proteins, ash and macro, micro, trace and ultra-trace elements. The highest protein content was recorded in the brown algae. Maximum dietary fiber and ash contents were recorded from green algae. The highest predominant fatty acids were observed from green seaweeds (Caulerpa racemosa); however, linoleic acid (C18:2n6) is the dominant fatty acid of all macroalgae. Mineral contents were highest in the red macroalga; however, copper, zinc and magnesium were also comparatively higher in green alga Ulva lactuca. In conclusion, 15 seaweed species belonging to the three different classes of seaweeds are investigated in detail to obtain their biochemical, mineral, and fatty acid compositions for the synthesis of novel therapeutic agents. In order to explore biorefinery processes for these seaweeds, as well as how they can potentially be cultivated, more extensive studies are required. Studying and determining the nutritional values of seaweeds will be beneficial with the potential for future industrial uses and research

Irreversible reorganization in a supercooled liquid originates from localised soft modes

The transition of a fluid to a rigid glass upon cooling is a common route of transformation from liquid to solid that embodies the most poorly understood features of both phases1,2,3. From the liquid perspective, the puzzle is to understand stress relaxation in the disordered state. From the perspective of solids, the challenge is to extend our description of structure and its mechanical consequences to materials without long range order. Using computer simulations, we show that the localized low frequency normal modes of a configuration in a supercooled liquid are causally correlated to the irreversible structural reorganization of the particles within that configuration. We also demonstrate that the spatial distribution of these soft local modes can persist in spite of significant particle reorganization. The consequence of these two results is that it is now feasible to construct a theory of relaxation length scales in glass-forming liquids without recourse to dynamics and to explicitly relate molecular properties to their collective relaxation.Comment: Published online: 20 July 2008 | doi:10.1038/nphys1025 Available from http://www.nature.com/nphys/journal/v4/n9/abs/nphys1025.htm

MERS-CoV antibody responses 1 Year after symptom onset, South Korea, 2015

We investigated the kinetics of the Middle East respiratory syndrome coronavirus (MERS-CoV) neutralizing and spike protein antibody titers over the course of 1 year in 11 patients who were confirmed by reverse transcription PCR to have been infected during the outbreak in South Korea in 2015. Robust antibody responses were detected in all survivors who had severe disease; responses remained detectable, albeit with some waning, for <1 year. The duration of viral RNA detection (but not viral load) in sputum significantly correlated with the antibody response magnitude. The MERS S1 ELISA antibody titers correlated well with the neutralizing antibody response. Antibody titers in 4 of 6 patients who had mild illness were undetectable even though most had evidence of pneumonia. This finding implies that MERS-CoV seroepidemiologic studies markedly underestimate the extent of mild and asymptomatic infection. Obtaining convalescent-phase plasma with high antibody titers to treat MERS will be challenging.published_or_final_versio

Comparison of serological assays in human Middle East respiratory syndrome (MERS)-coronavirus infection

Plaque reduction neutralisation tests (PRNT), microneutralisation (MN), Middle East respiratory syndrome (MERS)-spike pseudoparticle neutralisation (ppNT) and MERS S1-enzyme-linked immunosorbent assay (ELISA) antibody titres were compared using 95 sera from 17 patients with MERS, collected two to 46 days after symptom onset. Neutralisation tests correlated well with each other and moderately well with S1 ELISA. Moreover to compare antigenic similarity of genetically diverse MERS-CoV clades, the response of four sera from two patients sampled at two time periods during the course of illness were tested by 90% PRNT. Genetically diverse MERS-CoV clades were antigenically homogenous.published_or_final_versio

Does the addiction in online pornography affect the behavioral pattern of undergrad private university students in Bangladesh?

Anecdotal reports from Bangladesh indicated that some young adults were becoming addicted to online pornography similar to how others become addicted to gambling, drugs, and alcohol. Such behaviors can have social, academic, and behavioral implications in this population. This study investigated the association between consumption of online pornography and sociobehavioral patterns among students from a private university in Bangladesh.In total, 299 undergraduate students (70.6% male) at the First Capital University of Bangladesh were interviewed using a structured questionnaire. The questions included sociodemographic characteristics, online-based pornography consumption habits and sociobehavioral characteristics. Chi-square test and binary logistic regression analysis were performed to examine correlations between online pornography addiction and sociobehavioral factors such as socializing habits, nature of interactions, university attendance and study focus, sleeping habits, and consumption of main meals.The use of pornography was significantly higher among students who gathered late nights with their friends (58.4%, P < 0.001). Furthermore, those who frequently argue/fight with their friends (51.0%, P = 0.001) frequently fooled around with their friends (48.4%, P < 0.001) and those who did not go to bed on time (57.7%, P < 0.001) reported greater consumption of pornography. Students who fooled around with their friends and those did not go to bed on time were more than twice as likely to watch pornography than students who did not fool around, and those went to bed on time.The study provides the first overview of online pornography consumption. A significant proportion of male students consumed erotic materials online than females. Students who did not go to bed emerged to consume online pornography. Such behaviors can have negative impacts on studies education outcomes as well as wider social and moral impacts for students and the society as a whole. In this digital era, technology has invaded every aspect of our lives, with increasing access to the internet. Therefore, it is imperative to provide specifically designed pornography addiction education programs to educate students about the adverse effects of pornography. Furthermore, targeted treatment programs for sexual addiction, sexual abuse, and pornography abuse are needed to support the individuals who are addicted to pornography

Outcome of ACHD patients with non-inducible versus inducible IART undergoing cavo-tricuspid isthmus ablation: the role of empiric ablation

Purpose: Catheter ablation for supraventricular tachycardia (SVT) in adults with congenital heart disease (ACHD) is an important therapeutic option. Cavo-tricuspid isthmus (CTI)-dependent intraatrial re-entrant tachycardia (IART) is common. However, induction of sustained tachycardia at the time of ablation is not always possible. We hypothesised that performing an empiric CTI line in case of non-inducibility leads to good outcomes. Long-term outcomes of empiric versus entrained CTI ablation in ACHD patients were examined. / Methods: Retrospective, single-centre, case-control study over 7 years. Arrhythmia-free survival after empiric versus entrained CTI ablation was compared. / Results: Eighty-seven CTI ablations were performed in 85 ACHD patients between 2010 and 2017. The mean age of the cohort was 43 years and 48% were male. Underlying aetiology included ASD (31%), VSD (11.4%), AVSD (9.1%), AVR (4.8%), Fallot’s (18.4%), Ebstein’s (2.3%), Fontan’s palliation (9.2%) and atrial switch (13.8%). CTI-dependent IART was entrained in 59 patients whereas it was non-inducible in 28. The latter had an empiric CTI ablation. Forty-three percent of procedures were performed under general anaesthesia. There were no reported procedural complications. There was no significant difference in the mean procedure or fluoroscopy times between the groups (empiric vs entrained CTI; 169.1 vs 183.3 and 28.1 vs 19.9 min). Arrhythmia-free survival was 64.3% versus 72.8% (p value 0.44) in the empiric and entrained groups at 21 months follow-up. / Conclusions: Long-term outcomes after empiric and entrained CTI ablation for IART in ACHD patients are comparable. This is a safe and effective therapeutic option. In the case of non-inducibility of IART, an empiric CTI line should be considered in this cohort