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Optimization of entropy generation and thermal mechanism of MHD hybrid nanoliquid flow in a sinusoidally heated porous cylindrical chamber
No full textThe present computational investigation explores the fluid and thermal characteristics along with entropy generation due to buoyancy-driven magnetohydrodynamic (MHD) convective flow of aqueous hybrid nanoliquid filled in a nonuniformly heated porous cylindrical chamber. The fluid motion in the enclosure is modeled by Brinkman - extended Darcy model. The modeled equations are resolved by finite difference approach. The computations are conducted for Rayleigh number (103-105), Hartmann number (0-50), Darcy number (10-5-10-1), different nanoparticle shapes and nanoparticle volume fraction (Ag/MgO: 0-0.05) to understand the characteristic of flow, thermal and irreversibility distribution. With vast numerical simulations, the outcomes reveal that though the buoyancy force is greater, the fluidity cannot be enhanced unless the permeability and magnetic field strength are optimally maintained. As Ra, Ha and Da is varied respectively from 103 to 105, 50 to 0 and 10-5 to 10-1, the fluidity has been enhanced by 99.39%, 83.26% and 99.79%. Among all considered parametric combinations, it has been noticed that the choice of Ha = 0, Ra = 105, Da = 10-1 with proper ratio of nanoparticles enhance the system efficiency. However, minimal entropy generation can be achieved with greater Hartmann and lower Darcy numbers. Furthermore, it has been found that blade shaped nanoparticles lead to increase the performance of thermal system
Investigation of Added Value in Regional Climate Models for East Asian Storm Track Analysis
No full textStudies have shown that regional climate models (RCMs) can simulate local climates at a higher resolution for specific regions compared to global climate models (GCMs), making dynamic downscaling using RCMs a more effective approach. Therefore, RCMs have become valuable tools for evaluating the potential impacts of climate change on specific regions and for informing local adaptation strategies. To fully understand the added value (AV) of RCMs, it is essential to understand how the characteristics differ between land and ocean. The complex topography of East Asia, including land and sea, makes it a suitable region for evaluating the AV of RCMs. In this study, we compared two regional simulations that integrated the same RCMs but employed different GCMs from the Coordinated Regional Climate Downscaling Experiment for their ability to simulate storm tracks in East Asia. The results of the RCMs for the period from 1982 to 2005 were compared with their host Coupled Model Intercomparison Project GCM projections and high-resolution reanalysis. In mountainous regions, the AV of the RCMs weakened the bias of the GCM and improved its agreement with the reanalysis due to the dynamical process near the high-resolution topography. In plains and coastal areas, owing to the increase in horizontal resolution and clearly determined coastline in RCMs, small-scale phenomena are well represented, and the storm track of RCMs shows similar values to that of the GCM in maritime regions. This study demonstrates the value of RCMs for improving the accuracy of climate projections in East Asia, informing adaptation strategies, and enhancing climate research
Experimental design for observation of long beam-plasma instabilities
No full textDepending on the electron beam parameters there can appear three beam-plasma instabilities which might be critical in beam-driven plasma wakefield accelerators. Those three instabilities are the self-modulation instability (SMI), hose instability (HI), and current filamentation instability (CFI) or for a long beam, oblique two-stream instability (OTSI), respectively. In majority of the cases, the classification of these instabilities is not clear unless any seed for an instability is given. As an experimental design, we suggest a simple switching method among the three instabilities by sweeping beam transverse emittance and radial size. Particularly, we investigate the mixed case of SMI and HI, and discuss the resonant condition of HI
Respiratory protection strategies for the public in emergency response
No full textA strategy was established to minimize the stochastic effects of internal and external exposure to radioactive substances by wearing respiratory protection equipment (RPE) during an emergency evacuation. During the evacuation of residents in the event of a nuclear power plant accident, the stochastic effects of internal exposure caused by the inhalation of radioactive aerosol and external exposure due to accumulated radioactive particles in the filter medium of a mask must be minimized. The radioactivity concentration along an evacuation route considers atmospheric dispersion and the resuspension of particles deposited on surfaces. The effective dose due to internal exposure is evaluated using inhalation dose coefficients for each particle diameter. When the face seal leakage and filter medium penetration ratio for each particle diameter of the RPE (N95) is taken into consideration, the internal dose is reduced by 97.2%. Furthermore, the accumulated radioactivity in the filter medium decreases by 91.4% when the respirator is replaced every 48 h
Utilizing a Siloxane-Modified Organic Semiconductor for Photoelectrochemical Water Splitting
No full textWeexplore the potential of employing diketopyrrolopyrrole (DPP)based pi-conjugated OSs as a hole transport layer material inheteroatom-doped hematite (Ti-Fe2O3/Ge-Fe2O3) photoanodes for efficient photoelectrochemicalwater splitting. The siloxane-modified pi-conjugated polymer(P-Si) with a high carrier mobility and crystallinity revealedgreat potential to extract holes by forming a built-in potential withhematite photoanodes while showing high stability in an alkaline electrolytefor photoelectrochemical water oxidation. Because of the easy holeextraction and subsequent fast hole transport property of the P-Si interlayer between NiFe-(OH)( x ) and Ge-doped porous Fe2O3(Ge-PH), NiFe-(OH)( x )/P-Si/Ge-PH showed a 1.8-fold increasein photocurrent density (4.57 mA cm(-2) at 1.23 V-RHE) with a cathodic shift of the onset potential (0.735 V-RHE) and good stability for 65 h compared to Ge-PH. This studydemonstrates the successful use of inherently unstable pi-conjugatedOSs as a hole extracting/transport medium in a photoanode, addressingthe intrinsic recombination issues of hematite for efficient and stablewater splitting
A Novel Screening, Brief Intervention, and Referral to Treatment (SBIRT) Based Model for Mental Health in Occupational Health Implemented on Smartphone and Web-Based Platforms: Development Study With Results From an Epidemiologic Survey
No full textBackground: While the importance of mental health is well-recognized in the field of occupational health, implementation of effective strategies in the workplace has been limited by gaps in infrastructure, program comprehensiveness, coverage, and adherence. authors developed a Screening, Brief Intervention, and Referral to Treatment (SBIRT) based occupational mental health intervention, and implemented in a web-based format with a smartphone application. Methods: The SBIRT-based intervention was developed by a multidisciplinary team, including occupational health physicians, nurses, psychiatrists, and software developers. The following mental health areas were included, based on outcomes of an epidemiological survey conducted: insomnia, depression, anxiety, problematic alcohol use, and suicidal The viability of the two-step evaluation process utilizing a combination of the brief version and the full-length version of the questionnaire was examined using responses from the survey. The intervention was adjusted according to the survey results and expert opinions. Results: The epidemiological survey included 346 employees who completed the long-form version of mental health scales. These data were the used to confirm the diagnostic value of using a combination of short-form and long-form version of the scales for screening in the SBIRT model. The model uses a smartphone application for screening, provision of psychoeducation, and for surveillance. The universal methods of the model ensure it can be implemented by all occupational managers, regardless of their specialization in mental health. In addition to the two-step screening procedure to identify employees at-risk for mental health problems, the model includes a stepped care approach, based on risk stratification, to promote mental health education, management, and follow-up for continuous care. Conclusion: The SBIRT model-based intervention provides an easy-to-implement approach for the management of mental health in the workplace. Further studies are required to examine the effectiveness and feasibility of the model
A single-cell, time-resolved profiling of Xenopus mucociliary epithelium reveals nonhierarchical model of development
No full textThe specialized cell types of the mucociliary epithelium (MCE) lining the respiratory tract enable continuous airway clearing, with its defects leading to chronic respiratory diseases. The molecular mechanisms driving cell fate acquisition and temporal specialization during mucociliary epithelial development remain largely unknown. Here, we profile the developing Xenopus MCE from pluripotent to mature stages by single-cell transcriptomics, identifying multipotent early epithelial progenitors that execute multilineage cues before specializing into late-stage ionocytes and goblet and basal cells. Combining in silico lineage inference, in situ hybridization, and single-cell multiplexed RNA imaging, we capture the initial bifurcation into early epithelial and multiciliated progenitors and chart cell type emergence and fate progression into specialized cell types. Comparative analysis of nine airway atlases reveals an evolutionary conserved transcriptional module in ciliated cells, whereas secretory and basal types execute distinct function-specific programs across vertebrates. We uncover a continuous nonhierarchical model of MCE development alongside a data resource for understanding respiratory biology
Isolation and identification of extracellular matrix proteins from oil-based CASPERized mouse brains for matrisomal analysis
No full textThe extracellular matrix (ECM) components present within all tissues and organs help to maintain the cytoskeletal architecture and tissue morphology. Although the ECM plays a role in cellular events and signaling pathways, it has not been well studied due its insolubility and complexity. Brain tissue has a higher cell density and weaker mechanical strength than other tissues in the body. When removing cells using a general decellularization method to produce scaffolds and obtain ECM proteins, various problems must be considered because tissues are easily damaged. To retain the brain shape and ECM components, we performed decellularization in combination with polymerization. We immersed mouse brains in oil for polymerization and decellularization via OCASPER (Oil-based Clinically and Experimentally Applicable Acellular Tissue Scaffold Production for Tissue Engineering and Regenerative Medicine) and then isolated ECM components using sequential matrisome preparation reagents (SMPRs), namely, RIPA, PNGase F, and concanavalin A. Adult mouse brains were preserved with our decellularization method. Western blot and LCMS/MS analyses revealed that ECM components, including collagen and laminin, were isolated efficiently from decellularized mouse brains using SMPRs. Our method will be useful to obtain matrisomal data and perform functional studies using adult mouse brains and other tissues
