The Protective Effects of EMF-LTE against DNA Double-Strand Break Damage In Vitro and In Vivo

With the rapid growth of the wireless communication industry, humans are extensively exposed to electromagnetic fields (EMF) comprised of radiofrequency (RF). The skin is considered the primary target of EMFs given its outermost location. Recent evidence suggests that extremely low frequency (ELF)-EMF can improve the efficacy of DNA repair in human cell-lines. However, the effects of EMF-RF on DNA damage remain unknown. Here, we investigated the impact of EMF-long term evolution (LTE, 1.762 GHz, 8 W/kg) irradiation on DNA double-strand break (DSB) using the murine melanoma cell line B16 and the human keratinocyte cell line HaCaT. EMF-LTE exposure alone did not affect cell viability or induce apoptosis or necrosis. In addition, DNA DSB damage, as determined by the neutral comet assay, was not induced by EMF-LTE irradiation. Of note, EMF-LTE exposure can attenuate the DNA DSB damage induced by physical and chemical DNA damaging agents (such as ionizing radiation (IR, 10 Gy) in HaCaT and B16 cells and bleomycin (BLM, 3 μM) in HaCaT cells and a human melanoma cell line MNT-1), suggesting that EMF-LTE promotes the repair of DNA DSB damage. The protective effect of EMF-LTE against DNA damage was further confirmed by attenuation of the DNA damage marker γ-H2AX after exposure to EMF-LTE in HaCaT and B16 cells. Most importantly, irradiation of EMF-LTE (1.76 GHz, 6 W/kg, 8 h/day) on mice in vivo for 4 weeks reduced the γ-H2AX level in the skin tissue, further supporting the protective effects of EMF-LTE against DNA DSB damage. Furthermore, p53, the master tumor-suppressor gene, was commonly upregulated by EMF-LTE irradiation in B16 and HaCaT cells. This finding suggests that p53 plays a role in the protective effect of EMF-LTE against DNA DSBs. Collectively, these results demonstrated that EMF-LTE might have a protective effect against DNA DSB damage in the skin, although further studies are necessary to understand its impact on human health.     

超高压处理对羊骨胶原蛋白三级结构的影响

以羊骨胶原蛋白为研究对象，研究不同超高压压力对胶原蛋白微观形态、热变性温度、吡啶交联物以及空间结构的影响。试验结果表明:超高压处理的胶原蛋白的微观形态在压力100~300 MPa时出现短暂的聚合现象；当压力超过400 MPa时胶原蛋白结构又重新展开。差式扫描量热仪(DSC)结果显示:经超高压处理的胶原蛋白的变性温度由44.9 ℃(对照组)降为31.7 ℃；胶原蛋白吡啶交联物羟赖氨酸吡啶啉(HP)和赖氨酸吡啶啉(LP)的含量随超高压压力的增加、保压时间的延长而显著下降(P＜0.05)；HP和LP与超高压压力和保压时间呈极显著负相关(P＜0.01)。     

White polymer light-emitting diode materials with efficient electron injection backbone containing polyfluorene,oxadiazole and quinoxaline derivatives

Copolymer including dithienylquinoxaline (TQ) (<0.1 mol%) as a dopant and oxadiazole derivative as a side chain has been synthesized on a Polyfluorene (PF) backbone based on the Suzuki coupling reaction. The UV–vis spectra of polymers showed similar behaviors in the solution and on the film. However, PL spectra were similar to that of PF in solution, but the peak around 524 nm increased as the amounts of TQ were increased in the casting film. With increase in TQ, effective Forster energy transfer (from PF and PFOxd15 to TQ) was observed. According to CV measurement, HOMO and LUMO levels declined as the amount of oxadiazole derivative increased. In case of PFOxd15TQ10, the luminous efficiency and power efficiency were 1.23 cd/A and 0.64 lm/W, respectively with a maximum brightness of 6940 cd/m². CIE coordinates were close to pure white (0.33, 0.39).     

The comparison of joint kinematic error using the absolute and relative coordinate systems for human gait

Minimizing artifacts from skin movement is vital for acquiring more accurate kinematic data in human movement analysis. There are several stages that cause skin movement artifacts and these stages depend on the selection of the reference system, the error reduction method and the coordinate system in clinical gait analysis. Due to residual errors, which are applied to the Euler and Bryant angle methods in each stage, significant cumulative errors are generated in the motion analysis procedure. Thus, there is currently a great deal of research focusing on reducing kinematic errors through error reduction methods and kinematic error estimations in relation to the reference system. However, there have been no studies that have systematically examined the effects of the selected coordinate system on the estimation of kinematic errors, because most of these previous studies have been mainly concerned with the analysis of human movement using only the human models that are provided in the commercial 3D motion capture systems. Therefore, we have estimated the differences between the results of human movement analyses using an absolute coordinate system and a relative coordinate system during a gait, in order to establish which system provides a more accurate kinematic analysis at the ankle joint. Six normal adult subjects with no neurological or orthopedic conditions, lower extremity injuries, or recent history of lower extremity surgery were used in this study. The analysis was conducted at a walking speed of 1.35m/s. For the clinical estimation, we used a cardinal plane based on the segmental reference system and the differences were plotted on the planes. From this analysis, when a relative coordinate system was in the gait analysis, the average kinematic error occurring during the gait was determined to be 13.58mm, which was significantly higher than the error generated with an absolute coordinate system. Therefore, although the relative coordinate system can also be used to calculate the ankle joint center during the clinical gait analysis, the absolute coordinate system should be employed in order to obtain more accurate joint kinematic data. In addition, the results from this study can be used as a basis to select an appropriate coordinate system with regards to the diagnostic accuracy level required for various kinds of gait disorders. This paper was recommended for publication in revised form by Associate Editor Hong Hee Yoo Yong Hoon Rim received his B.S. and M.S degrees in Bio-Mechatronic engineering from Sungkyunkwan University in 2002 and 2004, respectively. Yong Hoon Rim is currently a Researcher at the Bio-Mechatronics center and also a candidate in the biomedical Ph.D. program at Sungkyunkwan University, Korea. His research interests are in the area of digital human modeling, workspace optimization and ergonomics in digital factory. Ahn Ryul Choi received his B.S. and M.S. degrees in Bio-Mechatronic engineering from Sungkyunkwan Univer-sity in 2005 and 2007, respectively. Ahn-Ryul Choi is curr-ently a Researcher at the Bio-Mechatronics center and also a candidate in the biomedical Ph.D. program at Sungkyunkwan University, Korea. His research interests are in the area of digital human modeling and simulation. Sang Sik Lee received his Ph.D. degree from Sungkyun-kwan Universi-ty in 2000. He is currently serving as a research professor at the Bio-Mechatronics center in Sungkyunkwan University. His research interests are in the area of digital human modeling and industrial ergonomics. Kyoung Kee Min received his Ph.D degree Sungkyunkwan University in 2008. Dr. Min is currently a researcher at the Bio-Mechatronics Center in Sungkyunkwan University. Dr. Min’s research interests are in the area of disease classification using artificial neural network, digital human modeling & control. Dong Hyuk Keum received his Ph.D. degree from Seoul National University in 1979. Dr. Keum is currently a Professor at the Department of Bio-Mechat- ronic engineering at Sungkyun-kwan University, Korea. He is currently serving as the chief of an evaluation committee of the Rural Development Administrator. Dr. Keum’s research interests are in the area of simulation of post-harvest systems, quality evaluation of food materials and the processing technology. Chang Hyun Choi received his Ph.D. degree from Iowa State University in 1988. Dr. Choi is currently a Professor at the Department of Bio-Mechatronic Engineering at Sungkyunkwan University, Korea. He is currently serving as an evaluation committee of the Rural Development Administration, Korea and Korea Industrial Technology Foundation. Dr. Choi’s research interests are in the area of nondestructive quality evaluation of foods, and automatic control of off-road machinery. Joung Hwan Mun received his Ph.D. degree majoring in mechanical engineering from the University of Iowa in 1998. Dr. Mun is currently a Professor at the Department of Bio-Mechat-ronic engineering at Sungkyun-kwan University in Suwon, Korea. He is currently serving as a director of the Bio-Mechatronics center with regard to an international IMS project. Dr. Mun’s research interests are in the area of digital human modeling, sports biomechanics, bio-electronics and digital factory for human oriented production system.     

Solvent Impregnated Polymers Loaded with Liquid-Like Nanoparticle Organic Hybrid Materials for Enhanced Kinetics of Direct Air Capture and Point Source CO2 Capture

Hybrid CO₂ capture materials, solvent impregnated polymers (SIPs), are developed based on a simple and scalable encapsulation technique to enhance CO₂ capture kinetics of water-lean solvents with high viscosity. Liquid-like nanoparticle organic hybrid materials functionalized with polyethylenimine (NOHM-I-PEI) are incorporated into a shell material and UV-cured to produce gas-permeable solid sorbents with uniform NOHMs loading (NPEI-SIPs). The CO₂ capture kinetics of NPEI-SIPs show a remarkable 50-fold increase compared to that of neat NOHM-I-PEI due to a large increase in the NOHMs-CO₂ interfacial surface area provided by the SIP design. The optimum NOHM-I-PEI loading and sorption temperature are found to be ≈49 wt% and 50 °C, respectively, and NPEI-SIPs exhibit great thermal stability over 20 CO₂ capture/sorbent regeneration temperature swing cycles. The pseudoequilibrium CO₂ loadings of NPEI-SIPs under humid conditions are as high as 3.1 mmol CO₂ g⁻¹_{NPEI − SIPs} for 15 vol% CO₂ (postcombustion capture) and 1.7 mmol CO₂ g⁻¹_{NPEI − SIPs} for 400 ppm (direct air capture). These findings suggest that NPEI-SIPs can effectively capture CO₂ from a wide range of CO₂ concentrations including direct air capture while allowing the flexible design of CO₂ capture reactors by combining the benefits of liquid solvents and solid sorbents.     

In the zone: Flow state and cognition in older adults.

The current study investigated the nature of the flow state among older adults. Flow is a pleasurable experiential state that occurs during full-capacity engagement in which an individual is performing at a level that is matched with the demands of the task. Each participant completed a scale assessing dimensions of flow in a particular activity selected by the participant. More cognitively demanding activities elicited higher levels of flow for those with higher fluid ability, but lower levels of flow for those with lower fluid ability. This pattern was reversed for activities that were low in demand. Our data highlight the potential importance of considering motivational states such as flow in understanding cognitive optimization in adulthood. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

A high image quality organic light‐emitting diode display with motion blur reduction for ultrahigh resolution and premium TVs

In this paper, we present a high image quality organic light‐emitting diode (OLED) display with motion blur reduction technology. Our latest work includes driving method that reduces motion blur using an adaptive black data insertion, brightness compensation technology, the simple structure pixel with low capacitance coupling for horizontal noise, and the multifunction integrated gate driver. The moving picture response time (MPRT) value of the OLED display panel with a fast response time was significantly affected by the frame frequency and the compensation driving method. The MPRT value of the large‐size OLED display panels was significantly decreased by using the integrated gate driver circuit with an MPRT reduction method. The decrease in the MPRT value originated from the turning of the emitting pixels off in advance resulting from providing black data. The integrated gate drivers were designed to achieve the normal display, the black data insertion, and the compensation mode. The MPRT value of the 65‐in. ultrahigh‐definition (UHD) OLED panels was decreased to 3.4 ms by using an integrated gate driver circuit. The motion blur of large‐size OLED display panels was significantly reduced due to a decrease in the MPRT value.