Extreme waves generated by Typhoon Bolaven (201215) in Southern Korean waters

Unusual extreme waves were generated by Typhoon Bolaven (201215) in the Southern Korean Waters\ud (SKW) and gave destructive damages to the breakwaters of Seogwipo Harbor at Jeju Island. The waves were far\ud exceeding the design wave height (Hs50yrs 9.3m) and their duration was 14hours. The duration is a very significant\ud factor as much as the design wave height for breakwater armor stability in terms of cumulative damages. A significant\ud increase in strong typhoon intensity and duration in North West Pacific (NWP) due to global warming has been reported\ud and also in landfall typhoons on Korea/Japan in a recent decade. The frequency of typhoon passed SKW region had an\ud inter-annual and also a decadal variation and decreased in recent years, but several strong typhoons were occurred.\ud Bolaven was affected by high pressure distribution located above the warm eddy region to track toward NNW rather\ud than NE as usual in August. The extreme waves were analyzed with respect to typhoon genesis, evolution of the waves\ud through extensive measured data and model simulation. Numerical models of TC96 for the wind fields and WAM4.5.2\ud for the waves were used after calibration with measured data and correction of Cd in wave growth term. They produced\ud reasonably good results. It was found that the extreme waves were evolved by combination of distant large swell and\ud strong wind seas generated by consistent strong winds from front right quadrant of typhoon track for such a long time.\ud The variation of those waves was relatively small as 1-2m, which might be due to limitation of wave growth for\ud U>30m/s and bottom energy dissipation of long period waves in the region. It is essential to hindcast accurately the\ud extreme waves for design of the breakwaters and also for assessment of coastal flooding and coastal erosion in a\ud warming climate

Precision Measurement of the Proton Flux in Primary Cosmic Rays from Rigidity 1 GV to 1.8 TV with the Alpha Magnetic Spectrometer on the International Space Station

A precise measurement of the proton flux in primary cosmic rays with rigidity (momentum/charge) from 1 GV to 1.8 TV is presented based on 300 million events. Knowledge of the rigidity dependence of the proton flux is important in understanding the origin, acceleration, and propagation of cosmic rays. We present the detailed variation with rigidity of the flux spectral index for the first time. The spectral index progressively hardens at high rigidities.</p

Soft X-ray Absorption Spectroscopic Investigation of Li(Ni0.8Co0.1Mn0.1)O-2 Cathode Materials

Herein, we report the soft X-ray absorption spectroscopic investigation for Li(Ni0.8Co0.1Mn0.1) O-2 cathode material during charging and discharging. These measurements were carried out at the Mn L-, Co L-, and Ni L-edges during various stages of charging and discharging. Both the Mn and Co L-edge spectroscopic measurements reflect the invariance in the oxidation states of Mn and Co ions. The Ni L-edge measurements show the modification of the oxidation state of Ni ions during the charging and discharging process. These studies show that e(g) states are affected dominantly in the case of Ni ions during the charging and discharging process. The O K-edge measurements reflect modulation of metal-oxygen hybridization as envisaged from the area-ratio variation of spectral features corresponding to t(2g) and e(g) states.11Yscopu

Photoactive poly(3-hexylthiophene) nanoweb for optoelectrical stimulation to enhance neurogenesis of human stem cells

Optoelectrical manipulation has recently gained attention for cellular engineering; however, few material platforms can be used to efficiently regulate stem cell behaviors via optoelectrical stimulation. In this study, we developed nanoweb substrates composed of photoactive polymer poly(3-hexylthiophene) (P3HT) to enhance the neurogenesis of human fetal neural stem cells (hfNSCs) through photo-induced electrical stimulation. Methods: The photoactive nanoweb substrates were fabricated by self-assembled one-dimensional (1D) P3HT nanostructures (nanofibrils and nanorods). The hfNSCs cultured on the P3HT nanoweb substrates were optically stimulated with a green light (539 nm) and then differentiation of hfNSCs on the substrates with light stimulation was examined. The utility of the nanoweb substrates for optogenetic application was tested with photo-responsive hfNSCs engineered by polymer nanoparticle-mediated transfection of an engineered chimeric opsin variant (C1V1)-encoding gene. Results: The nanoweb substrates provided not only topographical stimulation for activating focal adhesion signaling of hfNSCs, but also generated optoelectrical stimulation via photochemical and charge-transfer reactions upon exposure to 539 nm wavelength light, leading to significantly enhanced neuronal differentiation of hfNSCs. The optoelectrically stimulated hfNSCs exhibited mature neuronal phenotypes with highly extended neurite formation and functional neuron-like electrophysiological features of sodium currents and action potentials. Optoelectrical stimulation with 539 nm light simultaneously activated both C1V1-modified hfNSCs and nanoweb substrates, which upregulated the expression and activation of voltage-gated ion channels in hfNSCs and further increased the effect of photoactive substrates on neuronal differentiation of hfNSCs. Conclusion: The photoactive nanoweb substrates developed in this study may serve as platforms for producing stem cell therapeutics with enhanced neurogenesis and neuromodulation via optoelectrical control of stem cells. © Ivyspring International Publisher1111sciescopu

Construction of a Novel In Vitro Atherosclerotic Model from Geometry-Tunable Artery Equivalents Engineered via In-Bath Coaxial Cell Printing

As the main precursor of cardiovascular diseases, atherosclerosis is a complex inflammatory disorder that preferentially occurs in stenotic, curved, and branched arterial regions. Although various in vitro models are established to understand its pathology, reconstructing the native atherosclerotic environment that involves both co-cultured cells and local turbulent flow singling remains challenging. This study develops an arterial construct via in-bath coaxial cell printing that not only facilitates the direct fabrication of three-layered conduits with tunable geometry and dimensions but also maintains structural stability. Functional vascular tissues, which respond to various stimulations that induce endothelial dysfunction, are rapidly generated in the constructed models. The presence of multiple vascular tissues under stenotic and tortuous turbulent flows allows the recapitulation of hallmark events in early atherosclerosis under physiological conditions. Furthermore, the fabricated models are utilized to investigate the individual and synergistic functions of cell co-culture and local turbulent flows in regulating atherosclerotic initiation, as well as the dose-dependent therapeutic effect of atorvastatin. These outcomes suggest that the constructed atherosclerotic model via a novel fabrication strategy is a promising platform to elucidate the pathophysiology of atherosclerosis and seek effective drugs and therapies. ? 2020 Wiley-VCH GmbH11Nsciescopu