Congruence Matters: Volunteer Motivation, Value Internalization, and Retention

Volunteer research suggests that both altruistic and non-altruistic motivations may improve retention. We challenge the assumption that this is true for all volunteer work. Drawing on congruity theory of attitude change, we argue that volunteer motivation may lead to high (or low) retention when the volunteer experience is perceived as congruent (or incongruent) with their motivation. Specifically, altruistic motivation can lead to a low retention during a non-altruistic event, while non-altruistic motivation can increase the retention. Using data from a mega sports event, our findings demonstrate a negative effect of altruistic motivation on retention in a non-altruistic event. We discuss implications of the role of motivation-experience congruence in volunteer retention

The reemergence of long-term potentiation in aged Alzheimer's disease mouse model

Mouse models of Alzheimer’s disease (AD) have been developed to study the pathophysiology of amyloid β protein (Aβ) toxicity, which is thought to cause severe clinical symptoms such as memory impairment in AD patients. However, inconsistencies exist between studies using these animal models, specifically in terms of the effects on synaptic plasticity, a major cellular model of learning and memory. Whereas some studies find impairments in plasticity in these models, others do not. We show that long-term potentiation (LTP), in the CA1 region of hippocampal slices from this mouse, is impared at Tg2576 adult 6–7 months old. However, LTP is inducible again in slices taken from Tg2576 aged 14–19 months old. In the aged Tg2576, we found that the percentage of parvalbumin (PV)-expressing interneurons in hippocampal CA1-3 region is significantly decreased, and LTP inhibition or reversal mediated by NRG1/ErbB signaling, which requires ErbB4 receptors in PV interneurons, is impaired. Inhibition of ErbB receptor kinase in adult Tg2576 restores LTP but impairs depotentiation as shown in aged Tg2576. Our study suggests that hippocampal LTP reemerges in aged Tg2576. However, this reemerged LTP is an insuppressible form due to impaired NRG1/ErbB signaling, possibly through the loss of PV interneurons

High Density, Localized Quantum Emitters in Strained 2D Semiconductors

Two-dimensional chalcogenide semiconductors have recently emerged as a host material for quantum emitters of single photons. While several reports on defect and strain-induced single photon emission from 2D chalcogenides exist, a bottom-up, lithography-free approach to producing a high density of emitters remains elusive. Further, the physical properties of quantum emission in the case of strained 2D semiconductors are far from being understood. Here, we demonstrate a bottom-up, scalable, and lithography-free approach to creating large areas of localized emitters with high density (~150 emitters/um2) in a WSe2 monolayer. We induce strain inside the WSe2 monolayer with high spatial density by conformally placing the WSe2 monolayer over a uniform array of Pt nanoparticles with a size of 10 nm. Cryogenic, time-resolved, and gate-tunable luminescence measurements combined with near-field luminescence spectroscopy suggest the formation of localized states in strained regions that emit single photons with a high spatial density. Our approach of using a metal nanoparticle array to generate a high density of strained quantum emitters opens a new path towards scalable, tunable, and versatile quantum light sources.Comment: 45 pages, 20 figures (5 main figures, 15 supporting figures

Numerical Investigation of the Effect of Supersonic Air Temperature on the Mixing Characteristics of Liquid Fuel

The effect of supersonic air temperature on the mixing characteristics of liquid hydrocarbon fuel injected into three different supersonic airflows elevated in three steps from 373 K to 673 K was investigated numerically. Compressible Reynolds-averaged Navier–Stokes (RANS) equations were solved together with species conservation equation using ANSYS Fluent for two-phase flow simulations including fuel droplet breakup and evaporation. The turbulence model needed to close the RANS equations used the Shear Stress Transport (SST) k-ω model. The Eulerian–Lagrangian model was employed to track fuel droplets in mainstream air, and the Kelvin–Helmholtz and Rayleigh–Taylor (KH-RT) models were used to simulate the droplet breakup process. Numerical solutions were validated using experimental data. The higher the air temperature, the stronger the streamwise vortices downstream of the pylon. When the air temperature was 373 K, the liquid fuel hardly evaporated, but as the air temperature increased, and the mass fraction of the vaporized fuel and the mixing efficiency increased linearly downstream of the pylon. At air temperatures of 523 K and 673 K, the mixing efficiencies were 10% and 51% at the combustor outlet, respectively. The total pressure loss decreased slightly due to droplet evaporation as the temperature increased from 373 K to 673 K

Comparative analysis of the oral microbiome of burning mouth syndrome patients

Burning mouth syndrome (BMS) is a chronic pain condition accompanied by unpleasant burning sensations of the oral mucosa. While multiple factors were proposed for the etiology, evidence suggested a neuropathic pain origin while others suspected the use of antibiotics as the underlying cause. Interestingly, several reports demonstrated the intimate interaction of the nervous system and the microbiome. The current study aims to elucidate the correlation of the oral microbiome with the pathophysiology of the primary BMS. Microbiome samples obtained from the unstimulated whole saliva of 19 primary BMS patients and 22 healthy controls were sequenced and analyzed of the V3-V4 region of 16S rRNA gene. There was a distinct difference in the microbial composition between the BMS and the control groups at all taxonomic levels. Alpha diversity indexes of the oral microbiome were significantly lower in the BMS group. The samples were readily distinguished by multidimensional scaling analysis and linear discriminant analysis effect size. Streptococcus, Rothia, Bergeyella, and Granulicatella genus were dominant in the BMS group, while Prevotella, Haemophilus, Fusobacterium, Campylobacter, and Allorevotella genus were more abundant in the healthy group. Distinct microbiome signatures of BMS patients suggested a diagnostic value and a potential role in the pathogenesis of BMS.Y

Experimental Study on Efficiency of Floating Vertical Axis Wind Turbine with Variable-Pitch

This paper presents the efficiency of a floating vertical axis wind turbine with variable-pitch. A model was designed to use the lift force and drag force for blades with various pitch angles. The blade's pitch angle is controlled by the stopper. To validate the efficiency of the wind turbine discussed in this paper, a model test was carried out through a single model efficiency experiment and wave tank experiment. The parameters of the single model efficiency experiment were the wind speed, electronic load, and pitch angle. The wave tank experiment was performed using the most efficient pitch angle from the results of the single model efficiency experiment. According to the results of the wave tank experiment, the surge and pitch motion of a structure slightly affect the efficiency of a wind turbine, but the heave motion has a large effect because the heights of the wind turbine and wind generator are almost the same

Serum N-terminal proBNP, not troponin I, at presentation predicts long-term neurologic outcome in acute charcoal-burning carbon monoxide intoxication

<p><b>Objective:</b> This study aimed to investigate whether the serum N-terminal pro-brain natriuretic peptide (NT-proBNP) and troponin I levels at emergency department (ED) presentation predict long-term neurologic outcomes after acute charcoal-burning carbon monoxide (CO) poisoning.</p> <p><b>Methods:</b> This retrospective study included 220 patients suffering from charcoal-burning CO poisoning. The demographics, serum NT-proBNP and troponin I levels at ED presentation, treatment, clinical course during hospitalization, and long-term neurologic outcomes were collected.</p> <p><b>Results:</b> The median serum NT-proBNP level at presentation was 48.8 (16.5–259) pg/mL, and 78 patients (35.5%) had elevated troponin I (>0.04 ng/mL) after acute charcoal-burning CO poisoning. The upper NT-proBNP and elevated troponin I groups had higher prevalences of respiratory failure, hypotension, and myocardial injury during hospitalization and altered mentality (GCS ≤14) at discharge than the lower NT-proBNP and normal troponin I groups. The incidence of persistent severe neurologic sequelae at 25 months after acute CO poisoning was 10.9%. The upper NT-proBNP and elevated troponin I groups had a higher incidence of poor long-term neurologic outcome than the counterpart groups. Log-transformed NT-proBNP and elevated troponin I were associated with poor long-term neurologic outcome in the univariate analysis, but only the adjusted log-transformed NT-proBNP remained an independent factor in the multivariate analysis. Compared with a predictive model including previously proposed predictors, the addition of log NT-proBNP improved the diagnostic accuracy for predicting poor long-term neurologic outcome. The serum NT-proBNP values for predicting poor long-term neurologic outcome were 74.6 and 32.7 pg/mL at fixed sensitivities of 95 and 99%, respectively.</p> <p><b>Conclusions:</b> Elevated serum NT-proBNP at ED presentation is correlated with a risk of poor long-term neurologic outcome after discharge in cases of acute charcoal-burning CO poisoning. NT-proBNP could significantly improve the risk stratification of patients who will experience poor long-term neurologic outcome after CO poisoning. This potentially valuable marker should be further validated.</p

Theory for plasticity of face-centered cubic metals

The activation of plastic deformation mechanisms determines the mechanical behavior of crystalline materials. However, the complexity of plastic deformation and the lack of a unified theory of plasticity have seriously limited the exploration of the full capacity of metals. Current efforts to design high-strength structural materials in terms of stacking fault energy have not significantly reduced the laborious trial and error works on basic deformation properties. To remedy this situation, here we put forward a comprehensive and transparent theory for plastic deformation of face-centered cubic metals. This is based on a microscopic analysis that, without ambiguity, reveals the various deformation phenomena and elucidates the physical fundaments of the currently used phenomenological correlations. We identify an easily accessible single parameter derived from the intrinsic energy barriers, which fully specifies the potential diversity of metals. Based entirely on this parameter, a simple deformation mode diagram is shown to delineate a series of convenient design criteria, which clarifies a wide area of material functionality by texture control.X112622sciescopu

Effect of Metal Electrodes on Aging-Induced Performance Recovery in Perovskite Solar Cells.

For commercialization of perovskite solar cells (PSCs), it is important to substitute the alternative electrode for Au to decrease the unit cost. From the early stage, Ag exhibits a potential to be a good counter electrode in PSCs; however, there is an abnormal s-shaped J-V curve with the Ag electrode, and it is recovered as time passes. The perception of the aging-induced recovery process and refutation of the raised stability issues are required for commercial application of Ag electrodes. Herein, we compared the aging effect of PSCs with Ag and Au electrodes and found that only devices with Ag electrodes have a dramatical aging-induced recovery process. We observed the change of photoelectronic properties only in the devices with Ag electrodes as time passes, which mainly contributes to recovery of the s-shaped J-V curve. We verified the work function change of an aged Ag electrode and its mechanism by photoelectron spectroscopy analysis. By comparing the light stability under 1 sun intensity illumination, we can assure the practical stability of Ag electrodes in case of being encapsulated. This work suggests the profound understanding of the aging-induced recovery process of PSCs and the possibility of commercial application of Ag electrodes