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The coronavirus disease 2019 (COVID-19) pandemic has resulted in shortages of personal protective equipment (PPE) underscoring the urgent need for simple, efficient, and inexpensive methods to decontaminate SARS-CoV-2-exposed masks and respirators. We hypothesized that methylene blue (MB) photochemical treatment, which has various clinical applications, could decontaminate PPE contaminated with coronavirus.
The two arms of the study included: 1) PPE inoculation with coronaviruses followed by MB with light (MBL) decontamination treatment, and 2) PPE treatment with MBL for 5 cycles of decontamination (5CD) to determine maintenance of PPE performance.
MBL treatment was used to inactivate coronaviruses on three N95 filtering facepiece respirator (FFR) and two medical mask (MM) models. We inoculated FFR and MM materials with three coronaviruses, including SARS-CoV-2, and treated with 10 µM MB and exposed to 50,000 lux of white light or 12,500 lux of red light for 30 minutes. In parallel, integrity was assessed after 5CD using multiple US and international test methods and compared to the FDA-authorized vaporized hydrogen peroxide plus ozone (VHP+O3) decontamination method.
Overall, MBL robustly and consistently inactivated all three coronaviruses with 99.8 - to >99.9% virus inactivation across all FFRs and MMs tested. FFR and MM integrity was maintained after 5 cycles of MBL treatment, whereas one FFR model failed after 5 cycles of VHP+O3.
MBL treatment decontaminated respirators and masks by inactivating three tested coronaviruses without compromising integrity through 5CD. MBL decontamination is effective, low-cost and does not require specialized equipment, making it applicable in all-resource settings.
Accents in second language speech have multiple perceptual consequences, including breakdown in communication and undesirable judgments about accented speakers. Whereas perceived accents are likely influenced by various acoustic variables, it is not clear which acoustic variables influence the perceived accents the most and whether such important predictors of accents change as learners’ proficiency develops. Here we report a study that has examined acoustic sources of foreign accent in second language Japanese produced by American learners at different instructional levels, including beginning and intermediate late learners and early bilinguals. We collected speech samples from these learners as well as a control group of native speakers and measured 27 segmental and prosodic variables. These acoustic variables were related to accent rating scores obtained from native listeners. Confirmatory analyses showed that 24 out of 27 variables tested were reliably associated with listeners’ accentedness judgements. Exploratory analyses showed that prosodic features were most predictive of beginning to intermediate late learners’ accents, whereas vowel features were most predictive of early bilinguals’ accents. These results shed light on issues related to the acoustic sources of foreign accent and the development of second language speech.
Childhood trauma is a vulnerability factor for the development of obsessive–compulsive disorder (OCD). Empirical findings suggest that trauma-related alterations in brain networks, especially in thalamus-related regions, have been observed in OCD patients. However, the relationship between childhood trauma and thalamic connectivity in patients with OCD remains unclear. The present study aimed to examine the impact of childhood trauma on thalamic functional connectivity in OCD patients.
Magnetic resonance imaging resting-state scans were acquired in 79 patients with OCD, including 22 patients with a high level of childhood trauma (OCD_HCT), 57 patients with a low level of childhood trauma (OCD_LCT) and 47 healthy controls. Seven thalamic subdivisions were chosen as regions of interest (ROIs) to examine the group difference in thalamic ROIs and whole-brain resting-state functional connectivity (rsFC).
We found significantly decreased caudate-thalamic rsFC in OCD patients as a whole group and also in OCD_LCT patients, compared with healthy controls. However, OCD_HCT patients exhibited increased thalamic rsFC with the prefrontal cortex when compared with both OCD_LCT patients and healthy controls.
Taken together, OCD patients with high and low levels of childhood trauma exhibit different pathological alterations in thalamic rsFC, suggesting that childhood trauma may be a predisposing factor for some OCD patients.
Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
We explore R&D subsidies in a hybrid growth model which may exhibit semi-endogenous growth or fully endogenous growth. We consider two types of subsidies on variety-expanding innovation and quality-improving innovation. R&D subsidies on quality-improving innovation only have effects in the fully endogenous-growth regime, in which more subsidies cause an earlier activation of quality-improving innovation and increase the transitional/steady-state growth rate. R&D subsidies on variety-expanding innovation have contrasting effects in the two regimes. In the semi-endogenous-growth regime, more subsidies on variety-expanding innovation increase transitional growth but have no effect on steady-state growth. In the fully endogenous-growth regime, more subsidies on variety-expanding innovation continue to increase short-run growth but delay the activation of quality-improving innovation and reduce long-run growth. Increasing subsidies on variety-expanding (quality-improving) innovation makes the semi-endogenous-growth (fully endogenous-growth) regime more likely to emerge. Finally, we calibrate the model and find that under reasonable parameter values, the fully endogenous-growth regime is more likely to emerge.
Our objective was to examine the performance characteristics of a bladder stimulation technique for urine collection among infants presenting to the emergency department (ED).
This prospective cohort study enrolled a convenience sample of infants aged ≤ 90 days requiring urine testing in the ED. Infants were excluded if critically ill, moderately to severely dehydrated, or having significant feeding issues. Bladder stimulation consisted of finger tapping on the lower abdomen with or without lower back massage while holding the child upright. The primary outcome was successful midstream urine collection within 5 minutes of stimulation. Secondary outcomes included sample contamination, bladder stimulation time for successful urine collection, and perceived patient distress on a 100-mm visual analog scale (VAS).
We enrolled 151 infants and included 147 in the analysis. Median age was 53 days (interquartile range [IQR] 27–68 days). Midstream urine sample collection using bladder stimulation was successful in 78 infants (53.1%; 95% confidence interval [CI] 45–60.9). Thirty-nine samples (50%) were contaminated. Most contaminated samples (n = 31; 79.5%) were reported as “no significant growth” or “growth of 3 or more organisms”. Median bladder stimulation time required for midstream urine collection was 45 seconds (IQR 20–120 seconds). Mean VAS for infant distress was 22 mm (standard deviation 23 mm).
The success rate of this bladder stimulation technique was lower than previously reported. The contamination rate was high, however most contaminated specimens were easily identified and had no clinical impact.
Multiple cortical and subcortical regions have been shown to exhibit altered transcriptional states in association with schizophrenia (SZ) through gene expression studies. Select nuclei of the thalamus, a subcortical region, have been previously shown to have neuron and volume loss. These thalamic regions are reciprocally connected with areas of cortex which have been implicated in SZ. The thalamic anterior nucleus (AN) is of particular interest due to its reciprocal connectivity with the SZ-associated anterior cingulate cortex (ACC). To identify SZ-related gene expression changes we used whole genome microarray screening to compare transcriptional profiles of two thalamic regions, the AN and VPL (a lateral tier nucleus not considered SZ-impacted) in the same subject with SZ. The same microarray screening comparison was performed with the same regions in non-psychiatric controls (NC) subjects. Differentially expressed genes common to both analyses were removed from the SZ list to sharpen focus on disease-related genes. One-hundred thirty-six gene expression changes were identified. This list was used with DAVID functional annotation and Ingenuity pathway tools which indicated their involvement in endocytosis, neuron projection morphogenesis, and cytoskeleton organization. These findings further support the notion of schizophrenia being a “disease of the synapse.”
In this article, Si nanoparticle (NP) films were prepared by pulsed laser ablation (PLA) in the argon atmosphere of 10 Pa at room temperature under different pulse repetition rates from 1 to 40 Hz without the baffle. Different from the conventional PLA method, the substrates were placed below and parallel to the ablated plume axis. The obtained films containing NPs were characterized by scanning electron microscopy and Raman spectrometer. The experimental results under constant laser fluence demonstrate the strong dependence of the mean size and the area number density of NPs on the repetition rate. Specifically, with the increase of pulse repetition rate, the mean size of the NPs in the film first decreases and reaches its minimum at 20 Hz, and then increases after 20 Hz, and decreases again till 40 Hz. The area number density shows the contrary trend versus mean size. The in situ diagnostic results of Langmuir probe denote the ablated Si ion density increases monotonously with the increase of repetition rate, while the temperature is almost constant. Combining with the nucleation probability, the growth/aggregation duration of NPs in the “nucleation region” and the effect of the baffle, the influence of pulse repetition rate on the formation of NPs is addressed. It is found that the repetition rate impacts the growth modes of NPs (i.e., growth and aggregation). 1–20, 20–30, and 30–40 Hz, respectively, correspond to growth-, aggregation-, and growth-controlled rate ranges without the baffle; however, 1–10, 10–20, and 20–40 Hz, respectively, correspond to growth-controlled, aggregation/growth-coexisted, and aggregation-controlled rate ranges with the baffle.
The air gap technique (AGT) is an approach to radiation dose optimisation during fluoroscopy where an “air gap” is used in place of an anti-scatter grid to reduce scatter irradiation. The AGT is effective in adults but remains largely untested in children. Effects are expected to vary depending on patient size and the amount of scatter irradiation produced.
Fluoroscopy and cineangiography were performed using a Phillips Allura Fluoroscope on tissue simulation anthropomorphic phantoms representing a neonate, 5-year-old, and teenager. Monte Carlo simulations were then used to estimate effective radiation dose first using a standard recommended imaging approach and then repeated using the AGT. Objective image quality assessments were performed using an image quality phantom.
Effective radiation doses for the neonate and 5-year-old phantom increased consistently (2–92%) when the AGT was used compared to the standard recommended imaging approaches in which the anti-scatter grid is removed at baseline. In the teenage phantom, the AGT reduced effective doses by 5–59%, with greater dose reductions for imaging across the greater thoracic dimension of lateral projection. The AGT increased geometric magnification but with no detectable change in image blur or contrast differentiation.
The AGT is an effective approach for dose reduction in larger patients, particularly for lateral imaging. Compared to the current dose optimisation guidelines, the technique may be harmful in smaller children where scatter irradiation is minimal.
Viral pneumonia is an important cause of death and morbidity among infants worldwide. Transmission of non-influenza respiratory viruses in households can inform preventative interventions and has not been well-characterised in South Asia. From April 2011 to April 2012, household members of pregnant women enrolled in a randomised trial of influenza vaccine in rural Nepal were surveyed weekly for respiratory illness until 180 days after birth. Nasal swabs were tested by polymerase chain reaction for respiratory viruses in symptomatic individuals. A transmission event was defined as a secondary case of the same virus within 14 days of initial infection within a household. From 555 households, 825 initial viral illness episodes occurred, resulting in 79 transmission events. The overall incidence of transmission was 1.14 events per 100 person-weeks. Risk of transmission incidence was associated with an index case age 1–4 years (incidence rate ratio (IRR) 2.35; 95% confidence interval (CI) 1.40–3.96), coinfection as initial infection (IRR 1.94; 95% CI 1.05–3.61) and no electricity in household (IRR 2.70; 95% CI 1.41–5.00). Preventive interventions targeting preschool-age children in households in resource-limited settings may decrease the risk of transmission to vulnerable household members, such as young infants.
Abnormal effort-based decision-making represents a potential mechanism underlying motivational deficits (amotivation) in psychotic disorders. Previous research identified effort allocation impairment in chronic schizophrenia and focused mostly on physical effort modality. No study has investigated cognitive effort allocation in first-episode psychosis (FEP).
Cognitive effort allocation was examined in 40 FEP patients and 44 demographically-matched healthy controls, using Cognitive Effort-Discounting (COGED) paradigm which quantified participants’ willingness to expend cognitive effort in terms of explicit, continuous discounting of monetary rewards based on parametrically-varied cognitive demands (levels N of N-back task). Relationship between reward-discounting and amotivation was investigated. Group differences in reward-magnitude and effort-cost sensitivity, and differential associations of these sensitivity indices with amotivation were explored.
Patients displayed significantly greater reward-discounting than controls. In particular, such discounting was most pronounced in patients with high levels of amotivation even when N-back performance and reward base amount were taken into consideration. Moreover, patients exhibited reduced reward-benefit sensitivity and effort-cost sensitivity relative to controls, and that decreased sensitivity to reward-benefit but not effort-cost was correlated with diminished motivation. Reward-discounting and sensitivity indices were generally unrelated to other symptom dimensions, antipsychotic dose and cognitive deficits.
This study provides the first evidence of cognitive effort-based decision-making impairment in FEP, and indicates that decreased effort expenditure is associated with amotivation. Our findings further suggest that abnormal effort allocation and amotivation might primarily be related to blunted reward valuation. Prospective research is required to clarify the utility of effort-based measures in predicting amotivation and functional outcome in FEP.
Better understanding of interplay among symptoms, cognition and functioning in first-episode psychosis (FEP) is crucial to promoting functional recovery. Network analysis is a promising data-driven approach to elucidating complex interactions among psychopathological variables in psychosis, but has not been applied in FEP.
This study employed network analysis to examine inter-relationships among a wide array of variables encompassing psychopathology, premorbid and onset characteristics, cognition, subjective quality-of-life and psychosocial functioning in 323 adult FEP patients in Hong Kong. Graphical Least Absolute Shrinkage and Selection Operator (LASSO) combined with extended Bayesian information criterion (BIC) model selection was used for network construction. Importance of individual nodes in a generated network was quantified by centrality analyses.
Our results showed that amotivation played the most central role and had the strongest associations with other variables in the network, as indexed by node strength. Amotivation and diminished expression displayed differential relationships with other nodes, supporting the validity of two-factor negative symptom structure. Psychosocial functioning was most strongly connected with amotivation and was weakly linked to several other variables. Within cognitive domain, digit span demonstrated the highest centrality and was connected with most of the other cognitive variables. Exploratory analysis revealed no significant gender differences in network structure and global strength.
Our results suggest the pivotal role of amotivation in psychopathology network of FEP and indicate its critical association with psychosocial functioning. Further research is required to verify the clinical significance of diminished motivation on functional outcome in the early course of psychotic illness.
Background: This is an updated on-line survey of the awareness and knowledge of stroke and heart disease amongst Chinese-Canadians carried out in 2017. Methods: 1001 randomnly selected Chinese-Canadians from Toronto and Vancouver area. Results: 46% were > 45 years old and male to female ratio was: 49.3 : 50.8, with native language being Cantonese in 40%, Mandarin 24% and 31% English. 82% were Canadian citizens and 31% had been in Canada < 10 years. 44% were from Mainland China, 37% Hong Kong , 6% Taiwan and 12% were borned in Canada. 85% were able to name at least one symptom of heart attack (p=0.005) while 80% were able to name at least one symptom of stroke (p=0.0008). 85% would call 911 in response to symptoms of heart attack or stroke compared to only 20% in a previous 2004 telephone survey (p=0.00001) . Conclusions: There is a dramatic improvement in the awareness and knowledge of stroke and heart disease amongst Chinese-Canadians compared to a previous telephone survey in 2004. This significant change could be due to difference in survey technique, but these improvements could also be due to the ongoing health promotion efforts by the Chinese-Canadian Council in support of the Heart & Stroke Foundation.
Oats can be processed in a variety of ways ranging from minimally processed such as steel-cut oats (SCO), to mildly processed such as large-flake oats (old fashioned oats, OFO), moderately processed such as instant oats (IO) or highly processed in ready-to-eat oat cereals such as Honey Nut Cheerios (HNC). Although processing is believed to increase glycaemic and insulinaemic responses, the effect of oat processing in these respects is unclear. Thus, we compared the glycaemic and insulinaemic responses elicited by 628 kJ portions of SCO, OFO, IO and HNC and a portion of Cream of Rice cereal (CR) containing the same amount of available-carbohydrate (23 g) as the oatmeals. Healthy males (n 18) and females (n 12) completed this randomised, cross-over trial. Blood was taken fasting and at intervals for 3 h following test-meal consumption. Glucose and insulin peak-rises and incremental AUC (iAUC) were subjected to repeated-measures ANOVA using Tukey’s test (two-sided P<0·05) to compare individual means. Glucose peak-rise (primary endpoint, mean (sem) mmol/l) after OFO, 2·19 (sem 0·11), was significantly less than after CR, 2·61 (sem 0·13); and glucose peak-rise after SCO, 1·93 (sem 0·13), was significantly less than after CR, HNC, 2·49 (sem 0·13) and IO 2·47 (sem 0·13). Glucose iAUC was significantly lower after SCO than CR and HNC. Insulin peak rise was similar among the test meals, but insulin iAUC was significantly less after SCO than IO. Thus, the results show that oat processing affects glycaemic and insulinaemic responses with lower responses associated with less processing.
TAOS II is a next-generation occultation survey with the goal of measuring the size distribution of the small end of the Kuiper Belt (objects with diameters 0.5–30 km). Such objects have magnitudes r > 30, and are thus undetectable by direct imaging. The project will operate three telescopes at San Pedro Mártir Observatory in Baja California, México. Each telescope will be equipped with a custom-built camera comprised of a focal-plane array of CMOS imagers. The cameras will be capable of reading out image data from 10,000 stars at a cadence of 20 Hz. The telescopes will monitor the same set of stars simultaneously to search for coincident occultation detections, thus minimising the false-positive rate. This talk described the project, and reported on the progress of the development of the survey infrastructure.
This study explores the growth and welfare effects of monetary policy in a scale-invariant Schumpeterian growth model with endogenous human capital accumulation. We model money demand via a cash-in-advance (CIA) constraint on research and development (R&D) investment. Our results can be summarized as follows. We find that an increase in the nominal interest rate leads to a decrease in R&D and human capital investment, which, in turn, reduces the long-run growth rates of technology and output. This result stands in stark contrast to the case of exogenous human capital accumulation in which the long-run growth rates of technology and output are independent of the nominal interest rate. Simulating the transitional dynamics, we find that the additional long-run growth effect under endogenous human capital accumulation amplifies the welfare effect of monetary policy. Decreasing the nominal interest rate from 10% to 0% leads to a welfare gain that is equivalent to a permanent increase in consumption of 2.82% (2.38%) under endogenous (exogenous) human capital accumulation.
This paper highlights experimental and theoretical efforts dedicated to developing plasmonic-enhanced electrodes for the photo-electrochemical ethanol oxidation reaction (EOR) at room temperature in alkaline media. However, decoupling the electrocatalytic dark response from the plasmon-enhanced improvement presents a difficult challenge. To understand the plasmonic-enhancement of the photo-electrochemical EOR, multiple Au-Fe2O3 were fabricated and evaluated in parallel with discrete dipole approximation (DDA) modeling. Different Au-Fe2O3 were synthesized with Au nanoparticles located at variable positions within and/or on the Fe2O3 layer(s). The configurations investigated include thin film, embedded, surface and sandwich layered electrodes to facilitate optimal electrode design considerations for plasmonic-enhancement. The design strategies and configurations were guided by DDA simulations to assess absorption, scattering, and near-field enhancements within or near the semiconductor band edge, as well as the solution/electrode interface. For the different Fe2O3 loadings and Au nanoparticle sizes/distributions considered, it is determined that the Au-Fe2O3 surface configurations significantly enhanced the EOR in terms of a large positive current density enhancement, an increased photo-voltage and a lower onset potential relative to the other electrode designs.
In linear system, in-plane motions are decoupled from out-of-plane motions for planar frame structures. A theoretical method is proposed that permits the efficient calculations of modal characteristics of planar multi-story frame structures. There are 3 × m beam components for a planar m-story frame structure. By analyzing the transverse and longitudinal motions of each component simultaneously and considering the compatibility requirements across each frame joint, the undetermined variables of the entire m-story frame structure system can be reduced to six, regardless of the number of stories, and that can be determined by the application of the boundary conditions. The main feature of this method is to decrease the dimensions of the matrix involved in the finite element methods and certain other analytical methods.