Effect of Argon-Based Atmospheric Pressure Plasma Treatment on Hard Tissue Formation on Titanium Surface

In this paper, we suggest that the atmospheric pressure plasma treatment of pure titanium metal may be useful for improving the ability of rat bone marrow cells (RBMCs) to induce hard tissue differentiation. Previous studies have reported that the use of argon gas induces a higher degree of hard tissue formation. Therefore, this study compares the effects of plasma treatment with argon gas on the initial adhesion ability and hard tissue differentiation-inducing ability of RBMCs. A commercially available titanium metal plate was used as the experimental material. A plate polished using water-resistant abrasive paper #1500 was used as the control, and a plate irradiated with argon mixed with atmospheric pressure plasma was used as the experimental plate. No structural change was observed on the surface of the titanium metal plate in the scanning electron microscopy results, and no change in the surface roughness was observed via scanning probe microscopy. X-ray photoelectron spectroscopy showed a decrease in the carbon peak and the formation of hydroxide in the experimental group. In the distilled water drop test, a significant decrease in the contact angle was observed for the experimental group, and the results indicated superhydrophilicity. Furthermore, the bovine serum albumin adsorption, initial adhesion of RBMCs, alkaline phosphatase activity, calcium deposition, and genetic marker expression of rat bone marrow cells were higher in the experimental group than those in the control group at all time points. Rat distal femur model are used as in vivo model. Additionally, microcomputed tomography analysis showed significantly higher results for the experimental group, indicating a large amount of the formed hard tissue. Histopathological evaluation also confirmed the presence of a prominent newly formed bone seen in the images of the experimental group. These results indicate that the atmospheric pressure plasma treatment with argon gas imparts superhydrophilicity, without changing the properties of the pure titanium plate surface. It was also clarified that it affects the initial adhesion of bone marrow cells and the induction of hard tissue differentiation.     

Deuterium atomic density estimation in recombining plasmas using self‐absorption spectroscopy

Deuterium atomic density in the divertor region of fusion reactors is an important parameter. In this study, atomic density is estimated in the divertor simulator NAGDIS‐T by use of an absorption effect of Lyman‐β, of which the wavelength is in the vacuum ultraviolet (VUV). The calibration of the spectrometer in the VUV wavelength was performed by using a branching ratio method. The intensity ratio of Lyman‐β to Balmer‐α significantly decreased in detached plasmas because of radiation trapping. The atomic density was estimated by use of self‐absorption effect. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Study on the Gelling Behaviour of Low Concentration Gelatin Solutions in the Cooling Process

Abstract

The authors have already reported the examination of the gelling characteristics of gelatin solution by a thermal sensor method. At solution concentrations below 4%, the gelling process was studied by optical rotatory power measurement. In this paper, the cltanges of the molecular iveight distribution (MWD) in the gelling process during the cooling period were investigated. The MWD of the gelatin solution was measured at the gelling temperature by gel permeation chromatography. The concentration of the gelatin solution was more related to the gelling phenomena than the cooling temperature. Some differences were observed in the changes of MWD among the types of gelatins.     

Sol-gel transition of a mixture of gelatin and κ-carrageenan

Abstract

The characteristics of sol-gel transition of a mixture made by mixing two kinds of gelling agents of different nature, i.e. gelatin and carrageenan were examined. The sample solutions consisted of 3.00 wt % gelatin solution, 1.00 wt % κ-carrageenan solution and 4.00 wt% mixed solution which was prepared by mixing the said gelatin and carrageenan solutions in the ratio 3:1. In the experiment, the optical rotation and the dynamic viscoelasticity were measured under the same temperature change program. As the sample solutions were cooled, the carrageenan solution started to show a change in the specific rotation in the first place, followed by the mixed solution and finally the gelatin solution. The gelatin and the mixed solutions had the same increasing tendency in the specific rotation, whereas the carrageenan solution changed a little. When the mixed solution was chilled to set, it turned into a highly elastic gel. In the mixed solution, the gelation of carrageenan was found to precede that of gelatin.     

Emission spectrometry for discharge plasma diagnosis

Emission spectrometry in the atmospheric pressure discharge was carried out to understand the reaction mechanisms of active species because the discharge plasma process is significantly affected by gas components. In this research, N₂ second positive band and two band systems of NO such as NO-β band and NO-γ band were investigated by using a digital controlled spectrometer and an ICCD camera. When the dielectric pellets were placed on the needle-plate type electrode, emissions from both N₂ second positive band and NO-γ band were reduced along the electrode axis. The emissionratio between N₂ second positive band and NO-γ band was significantly different due to the existence of dielectric pellets. One dimensional analysis of emission spectral showed that NO-g band and N₂ second positive band lay between the needle-plate electrodes, while emission spectral of NO-β band existed around the needle electrode. Two-dimensional analysis of the emission spectrum showed that NO-γ band and N₂ second positive band exist between needle-plate electrodes. Observation by the time resolution of the emission spectrum showed that N₂ second positive band emission was extinguished within 200 ns, while that from NO-γ band continued for more than 1 μs.     

晶圆干燥缺陷的机理与控制

长期以来,人们对于硅片在经过HF湿法处理之后出现的水印早已有所认识,尤其是图形包含亲水和疏水层时最为明显。我们系统地研究了经过HF后道处理之缺陷形成的机理,并确认了与先前报道的水印截然不同的缺陷类型。根据X射线和其它分析表明,认为这些缺陷与周围环境残余的汽相HF和随后的晶圆表面反应有关。根据反应腔室HF浓度的不同可以产生不同类型的缺陷。由于水印是由硅在水中的氧化和随后产生的氧化物的分解形成的,少量的HF具有加速这个过程的效果。形成不同缺陷的条件,还有避免这些缺陷的策略均得以认定。正确的排空管理是一个关键的因素。最后发现,重参杂的硅更易产生缺陷。     

Hybrid peptides constructed from RES-701-1, an endothelin B receptor antagonist, and endothelin; binding selectivity for endothelin receptors and their pharmacological activity

Hybrid peptides were constructed from endothelin B receptor (ET(B)) selective antagonist RES-701-1 (1) and endothelin (ET-1). They have N-terminal 10 amino acids derived from 1 and C-terminal 10 amino acids derived from ET-1. RES-701-1(1-10)-[Ala15]ET-1(12-21) and its analogues substituted or truncated at the residues derived from RES-701-1 had proved to possess high receptor binding activity selective for ETB as well as 1. Substitutions at the residues derived from ET-1 had produced some analogues that possessed high affinity not only for ETB but for ETA. Although all analogues had antagonistic effects on ETA, some analogues had proved to function as agonist on ETB confirmed by the changes in intracellular calcium concentrations of ET receptor-transfected COS-7 cells. We have found four types of ET receptor-binding peptides: (1) ETB-selective agonist with weak ETA antagonism (3, KT7421); (2) ETB-selective antagonist with weak ETA antagonism (29, KT7539); (3) ETB agonist with potent ETA antagonism (27, KT7538); and (4) non-selective ETA/ETB antagonist (26, KT7540).     

Comparative conformational analyses of mu-selective dermorphin and delta-selective deltorphin-II in aqueous solution by 1H-NMR spectroscopy

Two-dimensional 1H-NMR methods have been used to obtain complete proton resonance assignments and possible solution conformations of dermorphin (H-Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2) and deltorphin-II (H-Tyr-D-Ala-Phe-Glu-Val-Val-Gly-NH2), naturally occurring mu- and delta-selective opioids, respectively, in order to examine the conformational characteristics that are closely related to the selectivities towards mu/delta-opioid receptors. With the use of the proton-proton distances derived from ROESY measurements in aqueous solution, 50 possible 3D structures are generated by means of distance geometry calculations. The conformers which satisfy the distance constraints and the torsion angles estimated from JNHC alpha H vicinal coupling constants within the allowable range are then subjected to molecular dynamics simulations for 10 ps after equilibration. Although dermorphin and deltorphin-II are both in equilibrium among many flexible conformers, some conformational differences are observed between these peptides: many conformers of dermorphin show a structure rounded at the N-terminal Tyr-D-Ala-Phe-Gly-Tyr and C-terminal Gly-Tyr-Pro-Ser-NH2 moieties, which are almost at right angles to each other, while those of deltorphin-II are characterized by a 'hook'-shaped backbone structure in which the nearly extended conformation of the Val-Val-Gly-NH2 sequence is located under the folded conformation of the N-terminal Tyr-D-Ala-Phe-Glu sequence. The possible relationship between these conformational characteristics and the mu/delta-opioid receptor selectivities is discussed.