Flow-Induced Voltage Generation Over Monolayer Graphene in the Presence of Herringbone Grooves

While flow-induced voltage over a graphene layer has been reported, its origin remains unclear. In our previous study, we suggested different mechanisms for different experimental configurations: phonon dragging effect for the parallel alignment and an enhanced out-of-plane phonon mode for the perpendicular alignment (Appl. Phys. Lett. 102:063116, 2011). In order to further examine the origin of flow-induced voltage, we introduced a transverse flow component by integrating staggered herringbone grooves in the microchannel. We found that the flow-induced voltage decreased significantly in the presence of herringbone grooves in both parallel and perpendicular alignments. These results support our previous interpretation

Strengthening the role of pediatric emergency centers in Korea

Since 2016, the pediatric emergency centers (PECs) have been selected by the Korean Ministry of Health and Welfare, but there are still many problems in their designation and operation. The authors, affiliated with the policy research team in the Korean Society of Pediatric Emergency Medicine, sought to identify the current status and plans for improvement of PECs in Korea. The problems in the designation and operation are the disproportionate regional distribution of the PECs, financial difficulties in meeting the designation criteria, and recruitment of dedicated pediatric emergency specialists. To improve this, it is necessary to designate additional PECs and analyze the appropriateness of insurance cost, to strengthen the role other than the community practice, and to reinforce back-up treatment by pediatric sub-specialists in PECs

Prevalence of Adrenal Insufficiency in Korean Patients undergoing Total Knee Arthroplasty

Background This study investigated the prevalence of adrenal insufficiency among patients admitted for total knee arthroplasty (TKA) due to osteoarthritis and identified factors contributing to adrenal insufficiency. Methods We divided the patients into two groups based on the results of preoperative standard-dose short synchronous stimulation tests: group 1 (adrenal insufficiency) and group 2 (normal adrenal function). We also assessed the prevalence of adrenal insufficiency and compared the numbers of patients who received oral steroids, the frequency of previous steroid injection use, and the frequency of systemic symptoms of steroid depletion such as fatigue and loss of appetite between the two groups. Multiple regression analysis was performed to identify factors related to adrenal insufficiency. Results The prevalence of adrenal insufficiency was 60.0% (120/200). Group 1 had higher numbers of previous steroid injections (12.8±10.2 vs. 6.8±7.9) and patients taking oral steroids (18/120 vs. 3/80) (p<0.001 and p=0.011, respectively). The frequency of systemic symptoms of steroid depletion, such as fatigue and loss of appetite, was also higher in group 1 (94/120 vs. 42/80, p<0.001). Recent steroid injections and loss of appetite were associated with adrenal insufficiency (p=0.002 and p=0.009, respectively). Conclusions The results of this study revealed a high prevalence of adrenal insufficiency in Korean patients hospitalized for TKA due to end-stage osteoarthritis. Recent steroid injections were causally related to the development of adrenal insufficiency. Therefore, adrenal function should be assessed preoperatively to prevent postoperative complications related to adrenal insufficiency

Visible emission from Ce-doped ZnO nanorods grown by hydrothermal method without a post thermal annealing process

Visible light-emitting Ce-doped ZnO nanorods [NRs] without a post thermal annealing process were grown by hydrothermal method on a Si (100) substrate at a low temperature of 90°C. The structural investigations of Ce-doped ZnO NRs showed that the Ce3+ ions were successfully incorporated into the ZnO lattice sites without forming unwanted Ce-related compounds or precipitates. The optical investigation by photoluminescence spectra shows that the doped Ce3+ ions in the ZnO NRs act as an efficient luminescence center at 540 nm which corresponds to the optical transition of 5d → 4f orbitals in the Ce3+ ions. The photoluminescence intensity of the Ce-doped ZnO NRs increased with the increasing content of the Ce-doping agent because the energy transfer of the excited electrons in ZnO to the Ce3+ ions would be enhanced by increased Ce3+ ions

Understanding NK cell biology for harnessing NK cell therapies: targeting cancer and beyond

Gene-engineered immune cell therapies have partially transformed cancer treatment, as exemplified by the use of chimeric antigen receptor (CAR)-T cells in certain hematologic malignancies. However, there are several limitations that need to be addressed to target more cancer types. Natural killer (NK) cells are a type of innate immune cells that represent a unique biology in cancer immune surveillance. In particular, NK cells obtained from heathy donors can serve as a source for genetically engineered immune cell therapies. Therefore, NK-based therapies, including NK cells, CAR-NK cells, and antibodies that induce antibody-dependent cellular cytotoxicity of NK cells, have emerged. With recent advances in genetic engineering and cell biology techniques, NK cell-based therapies have become promising approaches for a wide range of cancers, viral infections, and senescence. This review provides a brief overview of NK cell characteristics and summarizes diseases that could benefit from NK-based therapies. In addition, we discuss recent preclinical and clinical investigations on the use of adoptive NK cell transfer and agents that can modulate NK cell activity

Determining the influence of ship hull deformations caused by draught change on shaft alignment application using FE analysis

This paper was to address the shortcomings of current design practice to evaluate the stability of the shaft alignment for a 300,000 DWT Very Large Crude Oil Carrier. An enhanced approach using FE was applied to identify the influence of hull deformation on the alignment of the shafting system. The effectiveness of this method was demonstrated in comparison with Jack up technique. Analysis results showed that the hull deformation could be a key factor affecting the offset distortion of each bearing supporting the shaft line. Moreover, it was confirmed that the deformation pattern of cargo hold was opposite to the deformation of engine room structure when hull deformation occurred due to draught change of the case ship. As new research findings, they are believed to contribute significantly to the prevention of shaft damage associated with hull deformations, thereby improving the reliability of shaft alignment for similar types of vessels

Electronic structures of hexagonal RMnO3 (R = Gd, Tb, Dy, and Ho) thin films

We investigated the electronic structure of multiferroic hexagonal RMnO3 (R = Gd, Tb, Dy, and Ho) thin films using both optical spectroscopy and first-principles calculations. Using artificially stabilized hexagonal RMnO3, we extended the optical spectroscopic studies on the hexagonal multiferroic manganite system. We observed two optical transitions located near 1.7 eV and 2.3 eV, in addition to the predominant absorption above 5 eV. With the help of first-principles calculations, we attribute the low-lying optical absorption peaks to inter-site transitions from the oxygen states hybridized strongly with different Mn orbital symmetries to the Mn 3d3z2-r2 state. As the ionic radius of the rare earth ion increased, the lowest peak showed a systematic increase in its peak position. We explained this systematic change in terms of a flattening of the MnO5 triangular bipyramid

Patterned Si thin film electrodes for enhancing structural stability

A patterned film (electrode) with lozenge-shaped Si tiles could be successfully fabricated by masking with an expanded metal foil during film deposition. Its electrochemical properties and structural stability during the charge-discharge process were examined and compared with those of a continuous (conventional) film electrode. The patterned electrode exhibited a remarkably improved cycleability (75% capacity retention after 120 cycles) and an enhanced structural stability compared to the continuous electrode. The good electrochemical performance of the patterned electrode was attributed to the space between Si tiles that acted as a buffer against the volume change of the Si electrode