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Energy-Saving Smart Windows with HPC/PAA Hybrid Hydrogels as Thermochromic Materials
No full textHydroxypropyl cellulose (HPC) hydrogels exhibit thermal-responsive transparency change due to their temperature-sensitive miscible–immiscible transitions, making them promising thermochromic materials for fabricating energy-saving smart windows. However, their transition temperatures, named lower critical solution temperature (LCST), are too high for building window applications, and it is also challenging to reduce LCST to comfortable room temperature range (e.g., 26–28 °C) in hot seasons. In this work, we report smart windows prepared using poly(acrylic acid) (PAA)-modified HPC hydrogels and demonstrate that the LCST of the resulting HPC/PAA hybrid hydrogels can be effectively tuned by solution pH, from 44 to 10 °C with decreasing pH from 6.0 to 1.0. At pH 2.5, an optimized LCST at 26.5 °C has been achieved. The sandwich-structured smart window, composed of two glass panes and an optimized HPC/PAA hydrogel in between, shows a high visible-light transmittance (Tlum = 90.1%), excellent solar energy modulation (ΔTsol = 47.5%), outstanding heat-shielding performance, and excellent stability after 100 heating and cooling cycles. These optical properties outperform the reported thermosensitive cellulose-based materials, vanadium oxide based smart windows, and other thermosensitive hydrogel-based smart windows. Furthermore, HPC/PAA hydrogels are easy to prepare, nontoxic, biocompatible, low-cost, and environmentally friendly, making them very promising materials for energy-saving and climate-adaptable smart windows
Infodemic: the effect of death-related thoughts on news-sharing
Get PDFResearch on the sharing of fake news has primarily focused on the manner in which fake news spreads and the literary style of fake news. These studies, however, do not explain how characteristics of fake news could affect people’s inclination toward sharing these news articles. Drawing on the Terror Management Theory, we proposed that fake news is more likely to elicit death-related thoughts than real news. Consequently, to manage the existential anxiety that had been produced, people share the news articles to feel connected to close others as a way of resolving the existential anxiety. Across three experimental studies (total N = 416), we found that it was not news type per se (i.e., real versus fake news) that influenced news-sharing intentions; instead, it was the increased accessibility to death-related thoughts elicited from the content of news articles that motivated news-sharing. The findings support the Terror Management framework and contribute to the existing literature by providing an empirical examination of the underlying psychological motive behind fake news-sharing tendencies
Associations between suboptimal sleep and smoking, poor nutrition, harmful alcohol consumption and inadequate physical activity (‘SNAP Risks’): A comparison of people with and without a mental health condition in an Australian community survey
Get PDFIntroduction: People with a mental health condition experience disproportionate morbidity and mortality compared to the general population. This inequity has been largely attributed to a higher prevalence of chronic disease risk behaviours including smoking, poor nutrition, harmful alcohol consumption and inadequate physical activity (‘SNAP risks’). Suboptimal sleep is highly prevalent among people with a mental health condition and, as an identified risk behaviour for several chronic diseases, has been implicated as an additional contributor to this health inequity. Research involving people without a mental health condition suggests associations between poor sleep and each SNAP risk; however, interactions with mental health status have not been reported in an Australian population. This study explored associations between suboptimal sleep and all four SNAP risks, and assessed whether they vary by mental health status. Materials and Methods: A descriptive study (n = 1265) was undertaken using self-report data from a cross-sectional telephone survey of Australian adults. Based on national guidelines and recommendations that indicate when someone might be at risk of adverse health effects, SNAP risks and sleep variables were reduced to two levels: ‘at risk’ or ‘not at risk’; and ‘appropriate’ or ‘suboptimal’, respectively. Chi square tests and multivariable logistic regression models explored associations between suboptimal sleep, SNAP risks and mental health status. Results: Fifteen per cent (n = 184) of participants identified as having a mental health condition in the past 12 months. Being at risk of adverse health effects due to smoking had the strongest association with several measures of suboptimal sleep (ps < 0.05). Two-way interactions revealed that being at risk of adverse health effects due to alcohol use and physical inactivity resulted in a significantly greater likelihood of suboptimal sleep duration (OR 3.06, 95% CI 1.41 to 6.64; OR 3.06, 95% CI 1.41 to 6.69) and nap duration (OR 7.96, 95% CI 1.90 to 33.22), respectively, for people with a mental health condition compared to those without. Conclusions: The findings suggest associations between suboptimal sleep and smoking, risky alcohol consumption and physical inactivity, with the latter two perhaps being stronger among people with a mental health condition compared to those without such a condition. Poor sleep should be considered in interventions to address smoking, alcohol and physical activity; and vice versa. This study lends further support for the value of multirisk lifestyle interventions to promote physical and mental health for people with mental health conditions
Wellbeing of breastfeeding women in Australia and New Zealand during the COVID-19 pandemic: A cross-sectional study
Get PDFDuring the COVID-19 pandemic, breastfeeding women have experienced restricted access to support, placing them at increased risk of mental health concerns and limited breastfeeding assistance. This study investigated the effect of the pandemic on feeding choices and maternal wellbeing amongst breastfeeding mothers living in Australian and New Zealand. We conducted a cross-sectional online survey that examined feeding methods, maternal mental wellbeing, worries, challenges, and positive experiences during the pandemic. Most women were exclusively breastfeeding (82%). Partial breastfeeding was associated with perceived low milk supply and longer pregnancy duration during the pandemic. Reduced mental health and wellbeing was associated with lower levels of family functioning, increased perceived stress, and perinatal anxiety. Longer pregnancy duration during the pandemic was associated with lower mental health wellbeing scores, while higher perceived stress scores were reported for regions with higher COVID-19 infection rates and women with perceived low milk supply. Women reported that the pandemic resulted in less pressure and more time for family bonding, while worries about the pandemic, family health, and parenting challenges were also cited. Mental health concerns of breastfeeding women appear to be exacerbated by COVID-19, highlighting a critical need for access to mental health and broader family support during the pandemic
Unraveling the optimum latent structure of Attention-Deficit/Hyperactivity Disorder: Evidence supporting ICD and HiTOP frameworks
Get PDFAttention Deficit/hyperactivity disorder (ADHD) is conceptualized differently in the Diagnostic and Statistical Manual (DSM-5), the International Classification of Diseases-10 (ICD-10), and the Hierarchical Taxonomy of Psychopathology (HiTOP) frameworks. This study applied independent cluster confirmatory factor analysis (ICM-CFA), exploratory structure equation model with target rotation (ESEM), and the S-1 bi-factor CFA approaches to evaluate seven ADHD models yielded by different combinations of these taxonomic frameworks. Parents and teachers of a community sample of children (between 6 and 12 years of age) completed the Disruptive Behavior Rating Scale (for ADHD symptoms) and the Strengths and Difficulties Questionnaire (for validation). Our findings for both parent and teacher ratings provided the most support for the S-1 bi-factor CFA model comprised of (i) a g-factor based on ICD-10 impulsivity symptoms as the reference indicators and (ii) inattention and hyperactivity as specific factors. However, the hyperactivity-specific factor lacked clarity and reliability. Thus, our findings indicate that ADHD is best viewed as a disorder primarily reflecting impulsivity, though with a separable inattention (but no hyperactivity) component, i.e., “ADID (attention deficit/impulsivity disorder).” This model aligns with the HiTOP proposals
Modelling mass crowd using discrete event simulation: A case study of integrated tawaf and sayee rituals during Hajj
Get PDFHajj is a mass gathering event that takes place annually in Makkah, Saudi Arabia. Typically, around three million people participate in the event and perform rituals that involve their movements within strict space and time restrictions. Despite efforts by the Hajj organisers, such massive crowd gathering and movement cause overcrowding related problems at the Hajj sites. Several previous simulation studies on Hajj focused on the rituals individually. Tawaf, followed by Sayee, are two important rituals that are performed by all the pilgrims at the same venue on the same day. These events have a strong potential for crowd buildup and related problems. As opposed the previous works in the literature, in this paper we study these two events jointly, rather than separately. We use ExtendSim, a Discrete Event Simulation tool, to integrate the Tawaf and Sayee rituals into one model. The validated model was applied to a wide range of scenarios where different percentages of pilgrims were allocated to the various Tawaf and Sayee areas. The effect of such allocations on the time to complete Tawaf and Sayee indicate strategies for managing these two key Hajj rituals
Mitochondrial mistranslation modulated by metabolic stress causes cardiovascular disease and reduced lifespan
Get PDFChanges in the rate and fidelity of mitochondrial protein synthesis impact the metabolic and physiological roles of mitochondria. Here we explored how environmental stress in the form of a high-fat diet modulates mitochondrial translation and affects lifespan in mutant mice with error-prone (Mrps12ep/ep) or hyper-accurate (Mrps12ha/ha) mitochondrial ribosomes. Intriguingly, although both mutations are metabolically beneficial in reducing body weight, decreasing circulating insulin and increasing glucose tolerance during a high-fat diet, they manifest divergent (either deleterious or beneficial) outcomes in a tissue-specific manner. In two distinct organs that are commonly affected by the metabolic disease, the heart and the liver, Mrps12ep/ep mice were protected against heart defects but sensitive towards lipid accumulation in the liver, activating genes involved in steroid and amino acid metabolism. In contrast, enhanced translational accuracy in Mrps12ha/ha mice protected the liver from a high-fat diet through activation of liver proliferation programs, but enhanced the development of severe hypertrophic cardiomyopathy and led to reduced lifespan. These findings reflect the complex transcriptional and cell signalling responses that differ between post-mitotic (heart) and highly proliferative (liver) tissues. We show trade-offs between the rate and fidelity of mitochondrial protein synthesis dictate tissue-specific outcomes due to commonly encountered stressful environmental conditions or aging
Factors influencing the dynamics of a collapsed blue swimmer crab (Portunus armatus) population and its lack of recovery
No full textIdentification of key drivers of population dynamics and prediction of rates of population recovery following stock decline are crucial aspects of fisheries management. The abundance of a blue swimmer crab population (Portunus armatus) in Cockburn Sound, Western Australia, which once supported the largest commercial fishery for this short-lived species in the State, declined markedly and has remained low despite two commercial fishery closures. This study employed state-space biomass dynamics models to explore evidence for potential factors contributing to the lack of stock recovery, including fishing pressure, changes in primary production (using chlorophyll-a as a proxy) and depensatory stock-recruitment dynamics. Likelihood ratio test results indicated better statistical fits for models with production functions modified to account for chlorophyll-a or both depensation and chlorophyll-a. Models incorporating both depensation and chlorophyll-a provided the most biologically-feasible results (e.g. estimated intrinsic increase, , not near zero) and the estimated biomass trajectories were less uncertain. For all models, estimated annual harvest rates peaked in the late 1990s, prior to the first major stock decline, and again in 2009−12, when the fishery was briefly re-opened with tight management restrictions. Results for models including both depensation and chlorophyll-a indicated that stock productivity is positively-related to chlorophyll-a. Thus, below-average chlorophyll-a concentrations in Cockburn Sound in recent years, in combination with some form(s) of depensation (e.g. associated with predation pressure), may be preventing stock recovery. Despite a sustained period of very limited recreational fishing and no commercial fishing, stock recovery appears highly uncertain under current environmental conditions. The results of this study highlight the value of incorporating environmental data and alternative stock-recruitment assumptions when fitting production models to explore key factors influencing population dynamics
Common variants in Alzheimer’s disease and risk stratification by polygenic risk scores
Get PDFGenetic discoveries of Alzheimer’s disease are the drivers of our understanding, and together with polygenetic risk stratification can contribute towards planning of feasible and efficient preventive and curative clinical trials. We first perform a large genetic association study by merging all available case-control datasets and by-proxy study results (discovery n = 409,435 and validation size n = 58,190). Here, we add six variants associated with Alzheimer’s disease risk (near APP, CHRNE, PRKD3/NDUFAF7, PLCG2 and two exonic variants in the SHARPIN gene). Assessment of the polygenic risk score and stratifying by APOE reveal a 4 to 5.5 years difference in median age at onset of Alzheimer’s disease patients in APOE ɛ4 carriers. Because of this study, the underlying mechanisms of APP can be studied to refine the amyloid cascade and the polygenic risk score provides a tool to select individuals at high risk of Alzheimer’s disease
The role of mobile phones as a possible pathway for pathogen movement, a cross-sectional microbial analysis
Get PDFIntroduction
Mobile phones are used the world over, including in healthcare settings. This study aimed to investigate the viable microbial colonisation of mobile phones used by healthcare personnel.
Methods
Swabs collected on the same day from 30 mobile phones belonging to healthcare workers from three separate paediatric wards of an Australian hospital were cultured on five types of agar plate, then colonies from each phone were pooled, extracted and sequenced by shotgun metagenomics. Questionnaires completed by staff whose phones were sampled assisted in the analysis and interpretation of results.
Results and discussion
All phones sampled cultured viable bacteria. Overall, 399 bacterial operational taxonomic units were identified from 30 phones, with 1432 cumulative hits. Among these were 58 recognised human pathogenic and commensal bacteria (37 Gram-negative, 21 Gram-positive). The total number of virulence factor genes detected was 347, with 1258 cumulative hits. Antibiotic resistance genes (ARGs) were detected on all sampled phones and overall, 133 ARGs were detected with 520 cumulative hits. The most important classes of ARGs detected encoded resistance to beta-lactam, aminoglycoside and macrolide antibiotics and efflux pump mediated resistance mechanisms.
Conclusion
Mobile phones carry viable bacterial pathogens and may act as fomites by contaminating the hands of their users and indirectly providing a transmission pathway for hospital-acquired infections and dissemination of antibiotic resistance. Further research is needed, but meanwhile adding touching mobile phones to the five moments of hand hygiene is a simple infection control strategy worth considering in hospital and community settings. Additionally, the implementation of practical and effective guidelines to decontaminate mobile phone devices would likely be beneficial to the hospital population and community at large