Abstract
In this study, not only the flow field but the aerodynamic sound field around the axial flow fan were directly simulated using the lattice Boltzmann method (LBM). To validate the LBM results ...obtained in this study, they were compared with the experimental results in terms of the pressure rise performance characteristics. In order to investigate the change in the flow and sound fields due to different operating points, calculations were conducted at two operating points; one is the low flow rate point where the fan is stalled and the other is the high flow rate point where the flow field in the fan is sound. In the comparison of the performance characteristics, the calculation results showed good agreement with the experimental results, and the flow fields were well reproduced with high accuracy. The analysis in terms of the vortical flow structures and the relative velocity distributions showed that the tip vortex was generated by the pressure difference between both sides of the fan blade at the high flow rate point while at the low flow rate point the flow field near the fan tip was covered with the low velocity region and the leading edge separation occurred on the tip side of the fan blade. Therefore, it was confirmed from the flow field as well as the performance that the fan blade was stalled with the blade loading lost at the low flow rate point. Large pressure fluctuations on the fan blade surface were caused by the interaction with the tip vortex from the adjacent blade at the high flow rate point and the occurrence of leading edge separation at the low flow rate point. With regard to the comparison of the far field sound spectrum, the calculation results for both two flow rate points were in good agreement with the experimental results in a low frequency range, and the aerodynamic sounds generated from the fan were predicted well with the LBM simulation.
Summary
Background
Gender disparities in adult patients with asthma regarding its prevalence and severity are mainly due to enhanced type 2 T‐helper (Th2) cytokine production in female patients ...compared to that in male patients. However, the pathways mediating this effect remain unclear.
Objective
We aimed to determine the roles of two major subsets of dendritic cells (DCs) in females, specifically those displaying CD11b or CD103, during enhanced Th2 priming after allergen exposure, using an ovalbumin‐induced asthma mouse model.
Methods
Sex‐based differences in the number of DCs at inflamed sites, costimulatory molecule expression on DCs, and the ability of DCs to differentiate naïve CD4+ T cells into Th2 population were evaluated after allergen exposure in asthmatic mice. In addition, we assessed the role of 17β‐oestradiol in CD103+ DC function during Th2 priming in vitro.
Results
The number of CD11bhigh DCs and CD103+ DCs in the lung and bronchial lymph node (BLN) was increased to a greater extent in female mice than in male mice at 16 to 20 hours after ovalbumin (OVA) inhalation. In BLNs, CD86 and I‐A/I‐E expression levels and antigen uptake ability in CD103+ DCs, but not in CD11bhigh DCs, were greater in female mice than in male mice. Furthermore, CD4+ T cells cultured with CD103+ DCs from female mice produced higher levels of interleukin (IL)‐4, IL‐5, and IL‐13, compared with CD4+ T cells cultured with CD103+ DCs from male mice. The 17β‐oestradiol‐oriented enhancement of CD86 expression on CD103+ DCs after allergen exposure induced the enhanced IL‐5 production from CD4+ T cells.
Conclusions and Clinical Relevance
These findings suggest that with regard to asthma, enhanced Th2 cytokine production in females might be attributed to 17β‐oestradiol‐mediated Th2‐oriented CD103+ DCs in the BLN.
Background
Although neighborhood environmental factors have been found to be associated with cognitive decline, few longitudinal studies have focused on their effect among older adults living in ...rural areas. This longitudinal study aimed to investigate the effect of neighborhood environmental factors on cognitive decline among rural older adults.
Methods
The data of 503 older adults aged > 60 years who were living in Unnan City in Japan and had participated in two surveys conducted between 2014 and 2018 were analyzed. Cognitive function was assessed using the Cognitive Assessment for Dementia, iPad version 2. Elevation, hilliness, residential density, and proximity to a community center were measured using geographic information system. Logistic regression examined the effect of each neighborhood environmental factor (in quartiles: Q1-Q4) on cognitive decline.
Results
A total of 57 (11.3%) participants demonstrated a decrease in cognitive function at follow up. Elevation (Odds ratio (OR): 3.37, 95% Confidence Interval (CI): 1.11-10.20 for Q3 vs. Q1; OR: 5.43, 95% CI: 1.89-15.56 for Q4 vs. Q1) and hilliness (OR: 3.45, 95% CI: 1.46-8.11 for Q4 vs. Q1) were associated with a higher likelihood of cognitive decline. Residential density and distance to a community center were not associated with cognitive decline.
Conclusions
Elevated and hilly environments may increase risk of cognitive decline among rural older adults.
Key messages
Residents in mountainous regions tend to have limited accessibility to various living centers.
Those who live in elevated and hilly areas within the mountainous regions may have further limited accessibility and availability of locations where they can interact with others.
We sought to optimize a method for quantification of the calcium in the aortic-valvar complex for the prediction of significant paravalvular leak (PVL) after transcatheter aortic valve implantation ...(TAVI).
All patients had severe symptomatic aortic stenosis and were treated with balloon-expandable TAVI (Sapien/Sapien-XT, Edwards Lifesciences LLC, Irvine, CA, USA). In order to correct for precise annular sizing, only patients with available contrast computed tomography (CT) data for measurements were included (n = 198). Paravalvular leak was quantified using peri-procedural transoesophageal echocardiography by Valve Academic Research Consortium-2 (VARC-2) criteria (grade ≥ moderate was considered significant). A detailed region-of-interest methodology separated quantification of calcium in each of the aortic leaflets to that in the left ventricular outflow tract (LVOT) and was used to predict PVL in receiver operator characteristic curve analyses. For non-contrast scans, the greatest discriminatory value for PVL was seen at the 450 Hounsfield Unit (HU) threshold for detection (volume ≥626 mm(3)), whereas for contrast scans it was at 850 HU (≥235 mm(3)). Left ventricular outflow tract calcium predicted PVL but only as a binary variable with no incremental value of quantification. In a multivariable binary logistic regression model, annulus area ≥ prosthesis area (OR 3.5, 95% CI 1.5-8.2, P = 0.005), contrast leaflet calcium volume (850-HU threshold) ≥235 mm(3) (OR 2.8, 95% CI 1.2-6.7, P = 0.023), and presence of LVOT calcium (OR 2.8, 95% CI 1.2-7.0, P = 0.022) were independent predictors for PVL ≥ moderate.
Both leaflet and LVOT calcium are significant predictors of PVL and exert an important synergistic influence on this complication, even in appropriately sized valves. With careful attention to thresholds for detection, clinically relevant leaflet calcium volumes can be identified with either non-contrast or contrast CT scans.
Macroporous particle photocatalysts can be produced using polystyrene latex (PSL) colloidal templating (see figure), which can be used for organic waste degradation. The rate of degradation is ...similar to that of nanoparticles. Macroporous particles have lower mechanical mobilities than nanoparticles and can be easily collected and recovered for repeated use.
The peak of the luminescence spectrum of zinc oxide (ZnO) is usually observed above 500 nm (yellow region). By in‐situ growth of ZnO nanoparticles in a poly(ethylene glycol) (PEG) matrix, we have ...succeeded in producing ZnO/polymer composites with stable luminescence peaks down to 465 nm (blue region). The unbalanced precursor molarity approach, where the molarity of one precursor (LiOH) is several times larger than the molarity represented by a chemical reaction balance, was used. The blue luminescence, which was accompanied by an enhancement of luminescence intensity, was observed at very high LiOH concentrations. This was probably due to the simultaneous reduction in the crystalline size and improvement in the crystallinity. Doping ZnO nanoparticles with europium also generated a red luminescence at 616 nm, due to the 5D0 →7F2 transition of Eu ions.
Luminescent polymer–electrolyte nanocomposites containing nanoparticles as luminescent centers have been produced. Europium‐doped zinc oxide nanoparticles were used, which were grown in‐situ in a poly(ethylene glycol) matrix. Under ultraviolet irradiation between 320 and 380 nm, the emission color of the composite varies in the blue–yellow region, depending on the ZnO crystal size (see Figure). Red emission was produced under 466 nm excitation.
The progress of caries has conventionally been evaluated by checking changes in mineral density using transverse microradiography (TMR). Recent advances have seen development of a new measurement ...system, using in-air micro proton induced X-ray/gamma-ray emission (PIXE/PIGE). PIXE/PIGE enables analysis of distributions and concentrations of multiple mineral elements in a carious lesion. The aim of this study was to evaluate the effectiveness of PIXE/PIGE for investigating the development of root caries. In summary, we successfully established a multi-elemental sequential measuring method using in-air micro-PIXE/PIGE to identify the dynamic distributions and concentrations of Ca and F in human root dentin. The PIXE/PIGE potentially offers a useful advantageous technique for studying carious development by using as a combination with conventional techniques such as TMR and Micro-computed tomography (µCT).
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Controllability of particle size,chemical composition, and crystallinity are offered by the simple, general method for the synthesis of nanoparticles described here. A modified aerosol decomposition ...process is utilized in which salts are added to separate the nanocrystallites, resulting in nanoparticles of narrow size distribution (see Figure) and superior properties.
Distribution functions of annual income of companies are analyzed based on two company databases. A clear power law distribution consistent with the Zipf's law can be confirmed for Japanese companies ...over more than three decades in income scale. Similar distributions can be confirmed in some other countries. It is confirmed that such power laws hold in most of job categories with slightly modified exponents. An annual income of a company is about two orders of magnitude smaller than its total assets, and the growth rate distribution of income is nearly independent of the income size in contrast to the case of growth rate of assets.
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