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When fabricating a metal powder filter with a double-layered pore structure, which includes a microporous layer, by coating flake-shaped powder using the Wet Powder Spray (WPS) process, it is crucial to ensure that the coating is applied parallel to the surface of the metal powder filter. Failure to do so can result in a non-uniform pore structure, leading to a rapid decline in particle filtration efficiency. Therefore, it is necessary to improve the alignment of the coated flake-shaped powder on the filter surface. In this study, a metal powder filter with a double-layered pore structure was fabricated by applying a flake-shaped metal powder coating to a tube-shaped SUS316L powder filter using the WPS process. In order to improve the flake-shaped powder orientation of coating layer, the impact of the rolling process was investigated. The characteristics of the pores were analyzed based on the powder size and the rolling time. The microstructure of the fabricated metal powder filter was observed using an optical microscope, surface roughness, variations in thickness, and air permeability were analysed. [ABSTRACT FROM AUTHOR]

Generally, when fabricating porous filters using metal powder, about 1 to 2 wt% of a binder is added to increase the formability of the metal powder. If the binder is not completely removed through a debinding and sintering process, however it can cause defects such as discoloration and the generation of fine particles. In this study, a study was conducted to fabricate a plate-type porous stainless steel powder filter with a different pore structure without the use of a biner. First, the metal powder is charged into a ceramic mold to form a plate-shaped powder filter, and then covered with a ceramic top plate. In order to observe the pore properties according to the pressure, the unpressurized specimen and the specimen pressurized with a pressure of 30 MPa were then sintered at 1050? for one hour in a high vacuum atmosphere furnace. The microstructure of the sintered plate-shaped powder filter was observed through an optical microscope and in order to analyze its pore properties as a filter, gas permeability and porosity were measured using a capillary flow porometer and Archimedes' law. [ABSTRACT FROM AUTHOR]

In this study, a flake-shaped metal powder was coated on a tube shaped pre-sintered 316L stainless steel support using a wet powder spraying process to fabricate a double pore structure, and the pore characteristics were analyzed according to coating time and tube rotation speed. The thickness of the coated layer was checked via optical microscopy, and porosity was measured using image analysis software. Air permeability was measured using a capillary flow porometer. As a result of the experiment, the optimal rotation speed of the support tube was established as 200 rpm. When the rotation speed was fixed, the coating thickness and the coating amount of the double pore structure increased as the coating time increased. The porosity of the double pore structure was increased due to the irregular arrangement of the flake-shaped powder. The air permeability of the double pore structure decreased with increasing fine pore layer thickness. [ABSTRACT FROM AUTHOR]

Recently, 3D printing processes have been used to manufacture metal powder filters with manufacturing complex-shape. In this study, metal powder filters of various shapes were manufactured using the metal extrusion additive manufacturing (MEAM) process, which is used to manufacture three-dimensional structures by extruding a filament consisting of a metal powder and a binder. Firstly, filaments were prepared by appropriately mixing SUS316 powder with sizes ranging from 7.5 pm to 50 pm and a binder. These filaments were extruded at temperatures of 100°C to 160°C depending on the type of filament being manufactured, to form three types of cylindrical filter. Specimens were sintered in a high vacuum atmosphere furnace at 850°C to 1050°C for 1 hour after debinding. The specimens were analyzed for permeability using a capillary flow porometer, porosity was determined by applying Archimedes' law and microstructure was observed using SEM. [ABSTRACT FROM AUTHOR]

Background: Korea, as one of the fastest-aging countries worldwide, requires an improved healthcare service model for older adults. We evaluated the current healthcare system and developed a service model based on information and communication technologies (ICT) for use in older patients in long-term care facilities (LTCF). Methods: We conducted a qualitative literature review, focus group interviews (FGIs), and structured survey to identify the current technology use and status of healthcare systems. We then developed a web-based platform with necessary, high-priority, and usable content for the care of older patients in LTCF. Results: We reviewed 60 (23 hypertension, 18 diabetes, and 19 heart failure) articles on iinformation and communication technologies (ICT)-based disease management for clinical effectiveness and improved patient satisfaction. FGIs and structured surveys were used to evaluate the inconvenience in patient and medical information transfer between hospitals and cost and time required for its process. Accordingly, we confirmed the unmet need for an ICT-based service model for management, monitoring, and consultation among older patients and developed the Health-RESPECT (integrated caRE Systems for elderly PatiEnts using iCT), a service platform for older patients residing in LTCF. The medical information exchange system was used to transfer medical information. Health-RESPECT includes an established algorithm for evidence-based comprehensive geriatric assessment and customized management; chronic disease management; management of potentially inappropriate medications; rehabilitation; and consultation and videoconferencing. Conclusion: This study identified the current status and unmet needs of healthcare systems for older adults. We developed an ICT-based system to manage older institutionalized patients. However, the Health-RESPECT service model requires further validation. [ABSTRACT FROM AUTHOR]

A new relay-aided non-orthogonal multiple access (NOMA) technique is proposed for multi-cell uplink cellular networks in which each cell supports K single-antenna users by its respective base station (BS) equipped with N(4Z ≪K) antennas. Cooperative relaying transmission is used to accommodate more than one user per orthogonal resource block in the context of interference-limited cellular networks. With the proposed relayaided NOMA, an Alamouti structure of the desired symbol can further be generated at each BS free of interference, which gives rise to diversity gain of two. The proposed scheme does not require any channel state information (CSI) at users. Further, only limited CS! is required at relays and BSs, which can greatly reduce the control overhead. [ABSTRACT FROM PUBLISHER]

CpG, 5'-C-phosphate-G-3', islands (CGIs) have long been known for their association with enhancers, silencers, and promoters, and for their epigenetic signatures. They are maintained in embryonic stem cells (ESCs) in a poised but inactive state via the formation of bivalent chromatin containing both active and repressive marks. CGIs also occur within coding sequences, where their functional role has remained obscure. Intragenic CGIs (iCGIs) are largely absent from housekeeping genes, but they are found in all genes associated with organ development and cell lineage control. In this paper, we investigated the epigenetic status of iCGIs and found that they too reside in bivalent chromatin in ESCs. Cell type-specific DNA methylation of iCGIs in differentiated cells was linked to the loss of both the H3K4me3 and H3K27me3 marks, and disruption of physical interaction with promoter regions, resulting in transcriptional activation of key regulators of differentiation such as PAXs, HOXs, andWNTs. The differential epigenetic modification of iCGIs appears to be mediated by cell type-specific transcription factors distinct from those bound by promoter, and these transcription factors may be involved in the hypermethylation of iCGIs upon cell differentiation. iCGIs thus play a key role in the cell type-specific regulation of transcription. [ABSTRACT FROM AUTHOR]

We recently proposed an analytical model of a two-dimensional acoustic trapping of polystyrene beads in the ray acoustics regime, where a bead diameter is larger than the wavelength used. As its experimental validation, this paper demonstrates the transverse (or lateral) trapping of individual polystyrene beads in the near field of focused ultrasound. A 100 lm bead is immobilized on the central beam axis by a focused sound beam from a 30MHz single element lithium niobate transducer, after being laterally displaced through hundreds of micrometers. Maximum displacement, a longest lateral distance at which a trapped bead can be directed towards the central axis, is thus measured over a discrete frequency range from 24 MHz to 36MHz. The displacement data are found to be between 323.7 lm and 470.2 lm, depending on the transducer's driving frequency and input voltage amplitude. The experimental results are compared with their corresponding model values, and their relative errors lie between 0.9% and 3.9%. The results suggest that this remote maneuvering technique may be employed to manipulate individual cells through solid microbeads, provoking certain cellular reactions to localized mechanical disturbance without direct contact. [ABSTRACT FROM AUTHOR]

We fabricated a gas ionization sensor based on 3-D single-walled carbon nanotube (SWNT) networks suspended between ZnO nanorods using a chemical vapor deposition method. ZnO nanorods were grown on the pyramid-like protrusions of a textured Si substrate. The breakdown voltages and stability of the 3-D SWNT networks were measured and compared with those of a SWNT film synthesized on Si substrate. Our results show that 3-D SWNT networks on ZnO nanorods enable ionization gas sensors to be sensitive, selective, and highly stable devices. [ABSTRACT FROM PUBLISHER]