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Vaccines and therapeutics are urgently needed for the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we screen human monoclonal antibodies (mAb) targeting the receptor binding domain (RBD) of the viral spike protein via antibody library constructed from peripheral blood mononuclear cells of a convalescent patient. The CT-P59 mAb potently neutralizes SARS-CoV-2 isolates including the D614G variant without antibody-dependent enhancement effect. Complex crystal structure of CT-P59 Fab/RBD shows that CT-P59 blocks interaction regions of RBD for angiotensin converting enzyme 2 (ACE2) receptor with an orientation that is notably different from previously reported RBD-targeting mAbs. Furthermore, therapeutic effects of CT-P59 are evaluated in three animal models (ferret, hamster, and rhesus monkey), demonstrating a substantial reduction in viral titer along with alleviation of clinical symptoms. Therefore, CT-P59 may be a promising therapeutic candidate for COVID-19., Therapies and vaccines for COVID-19, caused by the SARS-CoV-2 viral pandemic, are urgently needed. Here the authors establish and screen an antibody library from a convalescent COVID-19 patient to isolate a neutralizing antibody with the ability to reduce viral titer and alleviate symptoms in ferret, hamster, and rhesus monkey infection models.

To investigate the mechanism of vascular endothelial growth factor (VEGF)-induced endothelin-1 production in human umbilical vein endothelial cells (HUVECs).Endothelin-1 levels were measured in conditioned medium of women with preeclampsia HUVECs were treated with different concentrations of VEGF(165) and at various time intervals. Next, we measured endothelin-1 levels after HUVECs were also incubated with VEGF and endothelin-converting enzyme-1 (ECE-1) inhibitor or tissue inhibitors of matrix metalloproteinase-2 (TIMP-2). Additionally, the circulating levels of total and free VEGF, matrix metalloproteinase-2 (MMP-2), and endothelin-1 were measured in 20 preeclamptic patients and 20 healthy pregnant controls.HUVECs treated with VEGF increased their endothelin-1 production in a concentration and time-dependent manner. The production of endothelin-1 was inhibited by TIMP-2, but not by the ECE-1 inhibitor. Total VEGF, MMP-2, and endothelin-1 concentrations were higher in preeclampsia and showed significant positive correlations between them.These findings suggest that VEGF-induced endothelin-1 production might be mediated by MMP-2 rather than by ECE-1 upregulation.

Microwave heating was utilized for low-temperature crystallization of amorphous Si (a-Si) films. Microwave heating lowered the annealing temperature and reduced the annealing time. By microwave heating the hydrogen in the amorphous films was diffused out long before the nucleation of polycrystalline Si (poly-Si). The combination of NiCl 2 coating on a-Si and microwave heating greatly reduced crystallization temperature. The combination of metal-induced crystallization and microwave-induced crystallization might be a useful technique to develop high-quality poly-Si films at low temperature.

Microwave heating was utilized for solid phase crystallization of amorphous silicon films. The amorphous silicon thin films were deposited in the temperature range of 100–400 °C by plasma enhanced chemical vapor deposition and annealed by microwave heating at 550 °C in nitrogen. Microwave heating lowered the annealing temperature and reduced the annealing time for complete crystallization. For example, the a-Si film deposited at 400 °C was fully crystallized in 3 h at 550 °C. On microwave heating, the hydrogen in the amorphous films diffused out very quickly, but there was no change in structural disorder following hydrogen evolution. The lower temperature crystallization of a-Si films compared to conventional furnace annealing is due to the interaction between microwave and silicon atoms. The grain size of the crystallized silicon films was in the range of 0.55–0.78 μm, depending on the deposition temperature. These grain sizes are not so small compared to those of Si films crystallized by conventional f...

Hydrogenated microcrystalline (Μc) silicon films were prepared by plasma enhanced chemical vapour deposition using an Ar-diluted SiH4 gas at various deposition conditions. The substrate temperature and RF power were varied from 150 to 400 ‡C and from 10 to 120 W, respectively. Structure and microstructure were examined by X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. Hydrogen bonding and optical properties were investigated by FTIR spectra and UV transmission spectra. The crystal fraction of the films increased as the deposition temperature decreased and RF power increased. More definite columnar morphology was developed with increasing crystal fraction. The existence of Μc-Si above a critical RF power (>30 W) suggests that SiH2 radical in plasma plays an important role for the formation of columnar morphology and Μc-Si. IR absorption analysis showed that the SiH2/SiH bonding ratio in the silicon films increased as the crystal fraction increased. The UV absorption coefficient of the films became smaller as the deposition temperature and RF power increased.

We found that a combination of the phalloidin (specific to F-actin) and the DAPI staining methods was a reliable method to distinguish primo vessels from vascular and lymphatic vessels. Also, we traced primo vessels in the mesentery of a mouse with a combination of the phalloidin and the DAPI staining methods and a whole mounting technique. We showed that primo vessels with a threadlike structure were distributed like a network in the mesentery between the colon and the root of the mesentery and were extended into the colon walls or fat tissues

We studied transparent organic light emitting diode (TOLED) with semitransparent cathode, Ca-Ag and optical enhanced passivation layer by annealing. The 8-hydroxyquinolatolithium (Liq) passivation layer improves the stability of Ca/Ag double layer, resulting in substantial increase of the efficiency by the enhanced transmittance and change brightness as electrode. Fabricated device was composed as followed structure, glass/ITO/2TNATA/α-NPD/Alq3:C545T (1%)/Bebq2/Ca-Ag. The passivation layer, Liq (40nm) was deposited on the device without broken vacuum before encapsulation with transparent glass sheets. Thermal annealing was carried out in oven at 80oC after encapsulation. At the device without passivation layer, annealing process made device to be deteriorated, such as to increase driving voltage from 6.8 V to 9.0 V at 10 mA/cm 2 and to drop efficiency 14.89 cd/A to 10.81 cd/A as bottom view. This drop of properties was caused by oxidation of cathode. However, the organic passivation layer played enough roles to protect oxidation of cathode. The efficiency as bottom side view of device with passivation layer, it can be observed that the efficiency and driving voltage were improved from 13.95 cd/A (@ 6.45 V) to 15.32 cd/A (@ 4.60 V) at 10 mA/cm 2 by annealing. Annealing process, in the device with passivation layer, made to increase the asymmetry of brightness through anode and cathode. So the ratio BBot/BTop of the emitted light through each electrode was changed from 2.26 to 4.33.

Solid phase crystallization of amorphous silicon films for poly-Si thin film transistors (TFTs) has advantages of low cost and excellent uniformity, but the crystallization temperature is too high. Using a microwave annealing method, we lowered the crystallization temperature and shortened the crystallization time. The complete crystallization time at 550/spl deg/C was within 2 h. The device parameters of TFTs with the poly-Si films crystallized by microwave annealing were similar to those of TFTs with the poly-Si films crystallized by conventional furnace annealing. The new crystallization method seems attractive because of low crystallization temperature, short crystallization time, and comparable film properties.

Solid phase crystallization has the advantages of low cost and excellent uniformity but the crystallization temperature is too high to use glass as a substrate. Using microwave annealing, we crystallized a-Si films at 550 °C within 3 h, which is much shorter than the annealing time at 600 °C of furnace annealing. We fabricated TFTs with poly-Si films crystallized by microwave annealing at low temperature and obtained the characteristics slightly better than or at least comparable to the TFTs by furnace annealing in spite of smaller grain size. This may be due to the improvement of surface roughness of poly-Si film. The poly-Si TFTs with PECVD a-Si film showed better characteristics than the TFTs with LPCVD a-Si film because of larger grain size and smoother Si/SiO2 interface.

We investigate the time series of the segments from a Korean traditional song ``Gwansanyungma'' and a western song ``La Mamma Morta'' using chaotic analysis techniques. It is found that the phase portrait in the reconstructed state space of the time series of the segment from the Korean traditional song has a more complex structure in comparison with the segment from the western songs. The segment from the Korean traditional song has the correlation dimension 4.4 and two positive Lyapunov exponents which show that the dynamic related to the Korean traditional song is a high dimensional hyperchaotic process. On the other hand, the segment from the western song with only one positive Lyapunov exponent and the correlation dimension 2.5 exhibits low dimensional chaotic behavior., Comment: 23 pages including 10 eps figures, latex, to appear in J. Acoust. Soc. Am

Microwave heating was utilized for the first time for solid phase crystallization of amorphous silicon films. Microwave heating lowered annealing temperature and reduced the annealing time for complete crystallization. For example, the amorphous silicon film deposited at 400 °C was fully crystallized in 3 h at 550 °C below which glass is available as a substrate. On microwave heating, the hydrogen in the amorphous films diffused out very quickly, but there was no change in structural disorder following hydrogen evolution. The lower temperature crystallization of a-Si films compared to conventional furnace annealing is due to the interaction between microwave and silicon atoms. The grain size of the crystallized silicon films was in the range of 0.55 to 0.78 μm, depending on the deposition temperature. These grain sizes are not so small comparing those of Si films by conventional furnace heating, while the crystallization processing time is much shorter.

We analyzed the color stability of blue phosphorescent organic light emitting diodes (phOLEDs) as device operation. In the blue phOLEDs, color stability is one of the most important factors during operation for commercialization. Therefore, we measure the electroluminance spectrum in the as-dep. state and after the lifetime test. The reference device with the whole emission layer doped shows a severe color change during the device operation owing to the degradation of the hole blocking property of the electron transport layer (ETL) and a shift of the emission region to ETL. After the lifetime test, the green peak increased and the width of the peak increased. The adoption of an undoped layer near the interface of ETL/emitting layer (EML) impeded the degradation of ETL thus so these devices show a stable color and a long lifetime. On the other hand, in the case of the undoped layer, the interface of hole transport layer (HTL)/EML shows an increased efficiency owing to the blocking of the movement of triplet energy from the doped layer to HTL, but does a color change that is similar to that of the reference device.

We investigated the solid phase crystallization (SPC) behavior of 1000 Å amorphous Si (a- Si) films deposited by plasma enhanced chemical vapor deposition (PECVD) at various temperatures and were able to enhance the grain size of the crystallized polysilicon films using double layers of a-Si filns. The deposition temperature of monolayer a-Si films varied from 200 to 400 °C and the films were recrystallized at 600 °C in nitrogen. As the deposition temperature increased, the incubation time was decreased and both the nucleation rate and growth rate were increased. Especially, the nucleation rate strongly depended on the deposition temperature.Since the Si-SiO2 interface provides a large number of nucleation sites, it is desirable to suppress nucleation at the interface. As an idea we employed a structure with double layer a-Si films. The bottom a-Si layer deposited at lower temperature could suppress the nucleation at the Si-SiO2 interface while the top a-Si layer deposited at higher temperature could nucleate with a smaller number of nucleation sites. The incubation time and transformation behavior were determined by the deposition temperature of the top layer. As an example, the grain size of the double layer film deposited sequentially at 150 °C and 200 °C enhanced to 1.8 μm while that of the monolayer film deposited at 200 °C was 1.4 μm.

The crystallization mechanism of amorphous Si films deposited on glass substrates by plasma enhanced chemical vapor deposition method was investigated. The deposition temperature varied from 200 to 400° C and the films were crystallized at 600° C in nitrogen. As the deposition temperature increased the nucleation rate was increased, but the nucleation activation energy was independent of the deposition temperature with a value of 3.8 eV. The results suggest that the pre-exponential factor in Arrhenius equation is dependent on the deposition temperature. The dependence of nucleation rate on deposition temperature was mainly due to the increased structural disorder during hydrogen evolution. The grain size was increased by introducing a double-layer structure of amorphous Si film, where the nucleation occurred other than at the Si/SiO2 interface.

We developed a new process for low-temperature crystallization of amorphous Si films, by adsorbing metal ions on the films. Amorphous Si films were deposited by low-pressure chemical vapor deposition, spin-coated by metal solutions and subsequently annealed in Ar atmosphere. The amorphous Si films coated with Cu and Au from 1000 ppm solutions almost completely crystallized at 530°C after 20 h. The fractal size of the Cu-adsorbed Si films was 30–50 µm at 530°C within 10 h. The application of Ag, Zn, Fe, Cr and Al solutions did not enhance crystallization of amorphous Si films. The enhancement of low-temperature crystallization by Cu and Au adsorption was deduced from the electronegativity, eutectic temperature and diffusion length. Secondary ion mass spectroscopy analysis indicated that the adsorbed Cu induced crystallization of amorphous Si films. The field-effect mobility of polycrystalline silicon thin-film transistors fabricated using the annealed Si films with Cu adsorption was 6–10 cm2/V·s before hydrogen passivation.