Multi-cellular natural killer (NK) cell clusters enhance NK cell activation through localizing IL-2 within the cluster

1154Ysciescopu

Growth of superconducting MgB2 thin films via postannealing techniques

We report the effect of annealing on the superconductivity of MgB2 thin films as functions of the postannealing temperature in the range from 700 C to 950 C and of the postannealing time in the range from 30 min to 120 min. On annealing at 900 C for 30 min, we obtained the best-quality MgB2 films with a transition temperature of 39 K and a critical current density of ~ 10^7 A/cm^2. Using the scanning electron microscopy, we also investigated the film growth mechanism. The samples annealed at higher temperatures showed the larger grain sizes, well-aligned crystal structures with preferential orientations along the c-axis, and smooth surface morphologies. However, a longer annealing time prevented the alignment of grains and reduced the superconductivity, indicating a strong interfacial reaction between the substrate and the MgB2 film.Comment: 7 pages, 4 figures include

Ethanol Extract of Dianthus chinensis L. Induces Apoptosis in Human Hepatocellular Carcinoma HepG2 Cells In Vitro

Dianthus chinensis L. is used to treat various diseases including cancer; however, the molecular mechanism by which the ethanol extract of Dianthus chinensis L. (EDCL) induces apoptosis is unknown. In this study, the apoptotic effects of EDCL were investigated in human HepG2 hepatocellular carcinoma cells. Treatment with EDCL significantly inhibited cell growth in a concentration- and time-dependent manner by inducing apoptosis. This induction was associated with chromatin condensation, activation of caspases, and cleavage of poly (ADP-ribose) polymerase protein. However, apoptosis induced by EDCL was attenuated by caspase inhibitor, indicating an important role for caspases in EDCL responses. Furthermore, EDCL did not alter the expression of bax in HepG2 cells but did selectively downregulate the expression of bcl-2 and bcl-xl, resulting in an increase in the ratio of bax:bcl-2 and bax:bcl-xl. These results support a mechanism whereby EDCL induces apoptosis through the mitochondrial pathway and caspase activation in HepG2 cells

Gd and B Based Integral Neutron Absorber for Spent Fuel Transportation and Storage System

Department of Nuclear EngineeringThis study presents the development of a new integral type neutron absorber design, characterized by the gadolinium (Gd) and boron (B) containing structural materials that enhance criticality safety and capacity for spent fuel transportation and storage system. The Gd and B stainless steel could act as both a structural member and a neutron absorbing member. It would help increase the storage capacity at equal volumes and decrease the manufacturing costs from removing the welding process between separate neutron absorber and sheathing. The sensitivity studies were conducted for optimizing design parameters of the pitch between fuel assemblies, the inner width of the cell and the thickness of the cell wall in spent fuel transportation and storage system. The neutron multiplication factors reduce with increasing pitch and decreasing inner width due to the flux trap. The flux trap increases with increasing pitch and decreasing inner width. The flux trap enhances the neutron thermalization. However, the keff shows the minimum at optimum thickness according to the contents of neutron absorbing materials and design parameters. When thickness increases, the quantity of neutron absorbing materials increase and, on the other hand, the flux trap decreases. From competing for two phenomena, the optimum thickness is decided. For reducing reactivity, the pitch should be maximum, and the inner width should be minimum when neutron absorber exists. The thickness of the cell wall is needed to be analyzed for specific neutron absorber content. However, large pitch occupies a large space to store the same amount of fuel assemblies. Only if the subcriticality is maintained, the pitch should be reduced for effective storage. The new neutron absorber, Gd and B stainless steel with optimized dimension was applied to spent fuel transportation and storage cask and spent fuel pool storage rack. For the flux trap type transportation and storage system, the spent fuel pool of Shin-kori units 3 and 4 was selected for the spent fuel storage pool and the KORAD-21 was selected for spent fuel storage cask. The possible combination of Gd and B stainless steel and the optimized dimension were analyzed. Maintaining subcriticality for accident conditions is critical. For SFP rack, the fuel assembly dropped in the region I and misloading of fresh fuel in region II were considered. For SFP cask, the eccentric position of the fuel assembly, flooding at various water height, flooding between pellet and cladding and loading of damaged fuel were analyzed. All accident conditions maintain subcriticality. The Gd and B stainless steel could ensure regulatory limits for accident conditions. In conclusion, the Gd and B stainless steel with an optimized dimension could improve criticality control. This neutron absorber could applicable to both spent fuel cask and rack. Also, it could be stored more fuel assemblies in the same space.clos

Corticosteroid Therapy for Children in Pediatric Emergency Department

Corticosteroids are effective and established treatments in various inflammatory and autoimmune disorders. These drugs have a potent anti-inflammatory effect and can be administered systemically or by inhalation, which can be combined with other treatments in the pediatric emergency department. Despite their beneficial effects, however, corticosteroid therapy is associated with many well-known side effects. Many of these side effects can be minimized through the lowest effective dose and duration required for the management of underlying conditions. The objectives of this article are to review a practical guide to corticosteroid therapy in the emergency department

Non-emergency department models for pediatric after-hours care

After-hours care (AHC) provides urgent primary care at nighttime, weekends, and holidays. In Korea, individual primary care physicians seldom participate in AHC and many parents have difficulty in receiving primary care during non-office hours without going to an emergency department (ED). The ED is currently the only place to access a full range of services at any time. However, the ED is not optimized for AHC, and using it for AHC is not an efficient use of resources. Therefore, many countries are seeking a safe, efficient non-ED AHC model which provides the best care considering the limitations. Different models for AHC exist worldwide, varying from family doctor-based to hospital-based models, and some countries use several different models including 24-hr telephone triage and advice services (TTA). Common problems of AHC include the inaccessibility to primary care, discontinuity of care, expensive healthcare costs, and work dissatisfaction among health care professionals. These are the major reasons for the recent changes made to the AHC system in many countries, such as the integration into one single national TTA in the United Kingdom, support for group practices in Canada, reorganization of small practice rotation groups into large scaled, general practitioner cooperatives in the Netherlands, and rapid expansion of the urgent care industry in the United States. This review presents a brief overview of the current AHC in Korea and the need for an effective non-ED AHC model. An effective AHC system will improve the quality of care, financial saving, and job satisfaction of the health care professionals