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The coronavirus disease 2019 (COVID-19) pandemic has led to significant strain on front-line healthcare workers.
In this multicentre study, we compared the psychological outcomes during the COVID-19 pandemic in various countries in the Asia-Pacific region and identified factors associated with adverse psychological outcomes.
From 29 April to 4 June 2020, the study recruited healthcare workers from major healthcare institutions in five countries in the Asia-Pacific region. A self-administrated survey that collected information on prior medical conditions, presence of symptoms, and scores on the Depression Anxiety Stress Scales and the Impact of Events Scale-Revised were used. The prevalence of depression, anxiety, stress and post-traumatic stress disorder (PTSD) relating to COVID-19 was compared, and multivariable logistic regression identified independent factors associated with adverse psychological outcomes within each country.
A total of 1146 participants from India, Indonesia, Singapore, Malaysia and Vietnam were studied. Despite having the lowest volume of cases, Vietnam displayed the highest prevalence of PTSD. In contrast, Singapore reported the highest case volume, but had a lower prevalence of depression and anxiety. In the multivariable analysis, we found that non-medically trained personnel, the presence of physical symptoms and presence of prior medical conditions were independent predictors across the participating countries.
This study highlights that the varied prevalence of psychological adversity among healthcare workers is independent of the burden of COVID-19 cases within each country. Early psychological interventions may be beneficial for the vulnerable groups of healthcare workers with presence of physical symptoms, prior medical conditions and those who are not medically trained.
Calcifying pseudoneoplasm of the neuraxis (CAPNON) is a rare tumor-like lesion with unknown pathogenesis. It is likely under-reported due to diagnostic challenges including the nonspecific radiographic features, lack of diagnostic markers, and often asymptomatic nature of the lesions.
We performed detailed examination of 11 CAPNON specimens diagnosed by histopathology, with the help of electron microscopy and immunohistochemistry.
Electron microscopy revealed the presence of fibrillary materials consistent with neurofilaments. In addition to some entrapped axons at the periphery of CAPNONs, we discovered that all specimens stained positive for neurofilament-light (NF-L) within the granular amorphous cores, but not neurofilament-phosphorylated (NF-p). CAPNONs also showed variable infiltration of CD8+ T-cells and a decreased ratio of CD4/CD8+ T-cells, suggesting an immune-mediated process in the pathogenesis of CAPNON.
NF-L and CD4/CD8 immunostains may serve as diagnostic markers for CAPNON and shed light on its pathogenesis.
Previous pharmacological, human genetical, and animal models have implicated the nicotinic acetylcholine receptor α4 subunit (CHRNA4) gene in the pathogenesis of ADHD. The objective of this study is to examine genetic association between single nucleotide polymorphisms (SNPs) in the CHRNA4 gene (rs2273502, rs1044396, rs1044397 and rs3827020 loci) and ADHD. Both case-control and family-based design were used in this study. Children aged 6 to 16 years were interviewed and assessed with the CBCL and CPRS-R to identify probands. No significant differences in frequency distribution of genotypes or alleles between the case and control groups were found. However, further haplotype analyses showed CCGG haplotype on risk for ADHD in 164 case-control sample and TDT analysis suggested that the allele C of rs2273502 over-transferred in 98 ADHD parent-offspring trios. Our findings suggest that CHRNA4 gene may play a role in the pathogenesis of ADHD, and further work is necessary to replicate and confirm what role the CHRNA4 gene may play in the etiology and pathogenesis of ADHD in large independent samples.
Studies suggest that alcohol consumption and alcohol use disorders have distinct genetic backgrounds.
We examined whether polygenic risk scores (PRS) for consumption and problem subscales of the Alcohol Use Disorders Identification Test (AUDIT-C, AUDIT-P) in the UK Biobank (UKB; N = 121 630) correlate with alcohol outcomes in four independent samples: an ascertained cohort, the Collaborative Study on the Genetics of Alcoholism (COGA; N = 6850), and population-based cohorts: Avon Longitudinal Study of Parents and Children (ALSPAC; N = 5911), Generation Scotland (GS; N = 17 461), and an independent subset of UKB (N = 245 947). Regression models and survival analyses tested whether the PRS were associated with the alcohol-related outcomes.
In COGA, AUDIT-P PRS was associated with alcohol dependence, AUD symptom count, maximum drinks (R2 = 0.47–0.68%, p = 2.0 × 10−8–1.0 × 10−10), and increased likelihood of onset of alcohol dependence (hazard ratio = 1.15, p = 4.7 × 10−8); AUDIT-C PRS was not an independent predictor of any phenotype. In ALSPAC, the AUDIT-C PRS was associated with alcohol dependence (R2 = 0.96%, p = 4.8 × 10−6). In GS, AUDIT-C PRS was a better predictor of weekly alcohol use (R2 = 0.27%, p = 5.5 × 10−11), while AUDIT-P PRS was more associated with problem drinking (R2 = 0.40%, p = 9.0 × 10−7). Lastly, AUDIT-P PRS was associated with ICD-based alcohol-related disorders in the UKB subset (R2 = 0.18%, p < 2.0 × 10−16).
AUDIT-P PRS was associated with a range of alcohol-related phenotypes across population-based and ascertained cohorts, while AUDIT-C PRS showed less utility in the ascertained cohort. We show that AUDIT-P is genetically correlated with both use and misuse and demonstrate the influence of ascertainment schemes on PRS analyses.
Lattice structures, defect structures, and deformation mechanisms of high-entropy alloys (HEAs) have been studied using atomistic simulations to explain their remarkable mechanical properties. These atomistic simulation techniques, such as first-principles calculations and molecular dynamics allow atomistic-level resolution of structure, defect configuration, and energetics. Following the structure–property paradigm, such understandings can be useful for guiding the design of high-performance HEAs. Although there have been a number of atomistic studies on HEAs, there is no comprehensive review on the state-of-the-art techniques and results of atomistic simulations of HEAs. This article is intended to fill the gap, providing an overview of the state-of-the-art atomistic simulations on HEAs. In particular, we discuss how atomistic simulations can elucidate the nanoscale mechanisms of plasticity underlying the outstanding properties of HEAs, and further present a list of interesting problems for forthcoming atomistic simulations of HEAs.
Deformation twinning has been frequently observed in body-centered cubic (BCC) high entropy alloys (HEAs), however, the underlying mechanism remains elusive. We perform molecular dynamics simulations on a representative BCC HEA nanopillar under high-symmetry compression, describe atomic details of deformation twinning, and propose a mechanism of twin nucleation from the surface. We find that twinned regions are formed by partial dislocations and that chemical heterogeneity can reduce local fault energy and promote stacking faults and twins. These results help to understand the propensity for stacking fault formation and twinning in HEAs and may guide the design of novel HEAs through control of active twinning mechanisms.
The insufficient depth of modelling to capture the flow physics within primary combustion zone is the prime reason behind limited accuracy of semi-empirical correlations. Flame volume concept establishes a better connection between LBO performance and flame parameters, which improves the modelling depth and hence the prediction accuracy. Nonetheless, estimation of flame parameters is a challenging task. In addition, the iterative loop to approach convergence for a single geometry demands several numerical simulation runs. In this study, the association of LBO performance has been extended to flow structures, they are uniquely associated with the geometric features and can efficiently relate global LBO performance with primary zone geometry. The lean blowout phenomenon was presented as a contest between igniting and extinction forces within Reverse Flow Zone. These forces were quantified by four performance parameters including area, minimum axial velocity, average temperature, and average velocity. Selected parameters provide valuable information regarding the size of recirculation bubble, the intensity of flow reversal and the amount of entrained hot gases. For the purpose of validation, 11 combustor geometries were selected. The RANS simulation was carried out to estimate performance parameters, and predicted performance was compared against experimental data. The excellent agreement highlights the efficiency and promising future for the proposed methodology. Moreover, the association of prediction process with flow structure, instead of geometric features/dimension, makes it universal prediction methodology for wide range of combustor configurations.
Angiostrongylus mackerrasae is a parasitic nematode of rats found in Australia. When first reported, it was referred to as A. cantonensis. Recent molecular studies, including the mitochondrial genome, indicate that it is highly similar to A. cantonensis. These studies did not include A. malaysiensis, another member of the A. cantonensis species complex, for comparison. The present study examined the genetic distance and phylogenetic relationship between the component taxa (A. cantonensis, A. mackerrasae and A. malaysiensis) of the A. cantonensis species complex, based on the 12 protein-coding genes (PCGs) of their mitochondrial genome. Both the nucleotide and amino acid sequences were analysed. Angiostrongylus mackerrasae and A. cantonensis are members of the same genetic lineage and both are genetically distinct from A. malaysiensis. The genetic distance based on concatenated nucleotide sequences of 12 mt-PCGs between A. mackerrasae and A. cantonensis from Thailand is p = 1.73%, while that between the Thai and Chinese taxa of A. cantonensis is p = 3.52%; the genetic distance between A. mackerrasae and A. cantonensis from China is p = 3.70%. The results indicate that A. mackerrasae and A. cantonensis belong to the same genetic lineage, and that A. mackerrasae may be conspecific with A. cantonensis. It remains to be resolved whether A. mackerrasae is conspecific with A. cantonensis or undergoing incipient speciation.
Femtosecond laser direct writing (FsLDW) in transparent materials is a laser-based precise three-dimensional (3D) micro/nanofabrication method that has shown great potential for applications. The advantages of FsLDW originate in the nonlinear nature of absorption in the multiphoton absorption process. Over the past few years, transparent material micro/nanofabrication using FsLDW has seen several developments in materials and applications. Specifically, two-photon polymerization has been widely used as a precision direct-writing process for fabrication of polymeric 3D micro/nanostructures; internal/surface ablation of polymer 3D structures based on multiphoton absorption has been demonstrated and developed as a promising subtractive manufacturing technique; and femtosecond laser multiphoton modification in glass has been intensively studied for refractive-index change and generation of nanogratings and microvoids. This article describes the latest research on FsLDW in polymers and glasses with specific applications for large-dimension fabrication, microelectromechanical systems, microphotonics, and microfluidics.
To investigate associations between eating frequency and energy intake, energy density, diet quality and body weight status in adults from the USA, combined data from the 2009–2010 and 2011–2012 National Health and Nutrition Examination Survey (NHANES) were used in this study. The first 24-h dietary recall data from eligible participants (4017 men and 3774 women) were used to calculate eating frequency, as well as energy intake, energy density and the Healthy Eating Index 2010 (HEI-2010), as a measure of diet quality. BMI and waist circumference were obtained from the NHANES body measures data. Adjusting for confounding socio-demographic characteristics and lifestyle factors, a higher eating frequency was significantly associated with higher energy intake in both men and women (both P<0·001). A higher eating frequency was also significantly associated with lower energy density in both men and women, regardless of whether beverage or water intake was included in the calculation of energy density (all P<0·01). Moreover, there was a significant positive association between eating frequency and the HEI-2010 total score in both men and women (both P<0·001). Eating frequency was inversely associated with BMI in women (P=0·003), as well as waist circumference in both men (P=0·032) and women (P=0·010). Results from the present study suggested that adults with a higher eating frequency in the USA had a healthier diet with lower energy density and better diet quality, and eating frequency was inversely associated with body weight status.
Introduction: Treatment of specific patterns of symptomatic hydrocephalus in the adult patient may be accomplished with endoscopic third ventriculostomy (ETV) as an alternative to insertion of a ventriculoperitoneal (VP) shunt. This review examines a single center experience with ETV to treat hydrocephalus in symptomatic adult patients. Methods: Adult patients (≥18 years) with a diagnosis of hydrocephalus who were treated with ETV in Calgary between January 1994 and July 2014 were reviewed using a clinic database and registry. Results: 163 patients were identified (male=92; female=71). Mean age at the time of ETV was 46.5 years (range 18-83.4 years). 118 underwent ETV as a primary treatment and 45 patients underwent treatment after presenting with VP shunt failure (secondary ETV). 113/163 patients had a diagnosis of aqueductal stenosis, 22/163 had a diagnosis of tumor. Mean followup was 8.2 years (range 0.3-18.4 years). Symptoms in 149/163 (91.4%) of ETV patients were better or unchanged at last followup. 104/118 (88.1%) of primary ETV patients were shunt free at last followup. 39/45 (86.7%) of secondary ETV patients were shunt free at last followup. Conclusion: Endoscopic (ETV) treatment is an effective long-term treatment for a select population of adult patients with hydrocephalus.
Introduction: Colloid cysts of the third ventricle are rare, histologically benign lesions that can be associated with obstructive hydrocephalus. Endoscopic removal developed as an alternative to microsurgical craniotomy as a less invasive surgical treatment. This review examines the endoscopic surgical experience for a consecutive series of patients with colloid cyst of the third ventricle. Methods: Patients with a diagnosis of “colloid cyst of the third ventricle” who were treated in Calgary between January 1994 and July 2014 were reviewed using a clinic database and registry. Results: 95 patients were identified. 30 patients without hydrocephalus underwent serial MRI and clinical observation with one patient developing hydrocephalus leading to surgical treatment. 65 patients underwent endoscopic treatment of their colloid cyst (male=34; female=31). The mean age at diagnosis was 45.5 years. 3 patients had been previously treated with other surgical approaches. All surgically treated patients had hydrocephalus and hydrocephalus resolved in all 65 patients. 1 patient sustained an injury to the internal capsule with transient hemiparesis. Mean followup was 8.2 years (range 0.1-19.3 years). 3 patients experienced colloid cyst recurrence treated with a second endoscopic removal. Conclusion: Endoscopic treatment of third ventricle colloid cysts can be performed with low risk as an alternative to microsurgical resection.
Transboundary haze pollution as a result of indiscriminate land clearance by fire has significant health and economic impacts on member states of the Association of South-east Asian Nations (ASEAN). Meanwhile the impact of the associated carbon emissions, ecological disturbance and biodiversity loss extends well beyond South-east Asia. This is despite the fact there are relatively well-established mechanisms to combat forest fires, and policy-level solutions have existed on paper for years. Although the fires are mostly in Indonesian territory, the involvement of multiple hierarchies of stakeholders in Indonesia, Malaysia and Singapore adds complexity to the quest for lasting solutions. A more robust approach is required from the region's governments, especially in instilling accountability among large companies, and this is feasible without increasing political tensions within ASEAN. Indonesia's ratification of the Haze Agreement is a significant development but needs to be complemented with actions at the local (e.g. grassroot initiatives in forest protection, firefighting, policing of illegal clearance practices), national (e.g. centralizing ministry-level control of forestry resources) and regional levels (e.g. implementing compliance mechanisms and legal standards to tackle haze and forest fires). Ultimately, actions to combat forest fires may also help secure the long-term conservation of biodiversity-rich peat swamps. Rather than being a source of discord, combating haze pollution could become South-east Asia's defining environmental project.
Global warming is a challenge to animal health, because of increased heat stress, with subsequent induction of immunosuppression and increased susceptibility to disease. Toll-like receptors (TLR) are pattern recognition receptors that act as sentinels of pathogen invasion and tissue damage. Ligation of TLRs results in a signaling cascade and production of inflammatory cytokines, which eradicate pathogens and maintain the health of the host. We hypothesized that the TLR signaling pathway plays a role in immunosuppression in heat-stressed pigs. We explored the changes in the expression of TLR2, TLR4 and the concentration of acute inflammatory cytokines, such as IL-2, IL-8, IL-12 and IFN-γ in Bama miniature pigs subjected to 21 consecutive days of heat stress, both in vitro and in vivo models. The results showed that heat stress induced the upregulation of cortisol in the plasma of pigs (P<0.05); TLR4 mRNA was elevated, but IL-2 was reduced in peripheral blood mononuclear cells (PBMC, P<0.05). The white blood cell count and the percentage of granulocytes (eosinophilic+basophilic) decreased significantly in heat-stressed pigs (P<0.05). In the in vitro model (PBMC heat shocked for 1 h followed by a 9 h recovery period), TLR2 and TLR4 mRNA expression also increased, as did the concentration of IL-12 in supernatants. However, IFN-γ was significantly reduced in PBMC culture supernatants (P<0.05). We concluded that a consecutive heat stress period elevated the expression of TLR2 and TLR4 in PBMC and increased the plasma levels of inflammatory cytokines. These data indicate that TLR activation and dysregulation of cytokine expression in response to prolonged heat stress may be associated with immunosuppression and increased susceptibility to antigenic challenge in Bama miniature pigs.
Mangroves are unique plant species found in tropical and subtropical estuarine and nearshore marine regions worldwide. Mangrove species have several physiological adaptations to saline, water-saturated soils, including viviparous or cryptoviviparous seeds that disperse by water, and salt-exclusion or salt-excretion capabilities to cope with high salt concentrations in nearshore saturated soils and sediments. Many species also have specialized aerial roots, or pneumatophores, that enable oxygenation of roots in water-logged soils. Species restricted to tropical intertidal habitat have been defined as “true mangrove” species, while those not exclusive to this habitat are sometimes referred to as “mangrove associates” (Lugo & Snedaker, 1974). Others include as mangroves any tree, shrub, palm, or ground fern exceeding 0.5 m in height and which normally grows in the intertidal zone of tropical coastal or estuarine environments (Duke, 1992). In view of the global variety of mangrove types and their floristics, there are approximately 70 species of mangroves, which are quite taxonomically diverse, as they represent 17 families (Table 2.1). The Mangrove Reference Database and Herbarium provides a larger overview of all known species, subspecies and hybrids (Massó i Alemán et al., 2010).
Recent ex situ observations of crystallization in both natural and synthetic systems indicate that the classical models of nucleation and growth are inaccurate. However, in situ observations that can provide direct evidence for alternative models have been lacking due to the limited temporal and spatial resolution of experimental techniques that can observe dynamic processes in a bulk solution. Here we report results from liquid cell transmission electron microscopy studies of nucleation and growth of Au, CaCO3, and iron oxide nanoparticles. We show how these in situ data can be used to obtain direct evidence for the mechanisms underlying nanoparticle crystallization as well as dynamic information that provide constraints on important energetic parameters not available through ex situ methods.
Epidemiological studies have revealed that soup consumption is associated with a lower risk of obesity. Moreover, intervention studies have reported that soup consumption aids in body-weight management. However, little is known about mechanisms that can explain these findings. The objective of the present study was to investigate associations between soup consumption and daily energy intake, dietary energy density (ED), nutrient intake and diet quality. Adults aged 19–64 years who participated in the National Health and Nutrition Examination Surveys during 2003–8 were included in the study. Soup consumers were identified from the first dietary recall using the United States Department of Agriculture food codes and combination food type from the dietary data. Compared with non-consumers (n 9307), soup consumers (n 1291) had a lower body weight (P= 0·002), a lower waist circumference (P= 0·001) and a trend towards a lower total energy intake (P= 0·087). Soup consumption was associated with a lower dietary ED (P< 0·001); this was independent of whether data on beverage or water consumption were included. Diet quality, as measured by the Healthy Eating Index 2005, was significantly better in soup consumers (P= 0·008). Soup consumption was also associated with a reduced intake of total fat and an increased intake of protein, carbohydrate and dietary fibre, as well as several vitamins and minerals (P< 0·05 for all). However, it was also associated with a higher intake of Na (P< 0·001). The relationship between soup consumption and body weight could be due to a reduced dietary ED and an improved diet quality. Consumers need to pay attention to their Na intake and choose low-Na products for a healthier diet.