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181.
We performed neutron polarization analysis (NPA) of extracted organic phases containing complexes, comprised of Zr(NO3)4 and tri-n-butyl phosphate, which enabled decomposition of the intensity distribution of small-angle neutron scattering (SANS) into the coherent and incoherent scattering components. The coherent scattering intensity, containing structural information, and the incoherent scattering compete over a wide range of magnitude of scattering vector, q, specifically when q is larger than q* ≈ 1/Rg, where Rg is the radius of gyration of scatterer. Therefore, it is important to determine the incoherent scattering intensity exactly to perform an accurate structural analysis from SANS data when Rg is small, such as the aforementioned extracted coordination species. Although NPA is the best method for evaluating the incoherent scattering component for accurately determining the coherent scattering in SANS, this method is not used frequently in SANS data analysis because it is technically challenging. In this study, we successfully demonstrated that experimental determination of the incoherent scattering using NPA is suitable for sample systems containing a small scatterer with a weak coherent scattering intensity, such as extracted complexes in biphasic solvent extraction systems. 相似文献
182.
The preparation of the highly refractive transparent TiO2-dispersed microspheres with uniform size was studied. These nanocomposite microspheres were prepared via TiO2 dispersion in an acrylic monomer and the emulsification by the Shirasu porous glass (SPG) membrane technique. Two kinds of the dispersion methods (bead mill dispersion with fine beads and ultrasonic dispersion) were carried out. The suspension prepared by bead mill included well-dispersed TiO2 nanoparticles and led to the uniformly sized TiO2-dispersed microspheres. It was indicated that the dispersibility of TiO2 in a monomer was the important factor in this process. 相似文献
183.
K Inamori T Saito D Iwaki T Nagira S Iwanaga F Arisaka S Kawabata 《Canadian Metallurgical Quarterly》1999,274(6):3272-3278
A 14-kDa lectin, named tachylectin-3, was newly identified from hemocytes of the Japanese horseshoe crab, Tachypleus tridentatus. This lectin exhibited hemagglutinating activity against human A-type erythrocytes, but not against the B- and O-types of erythrocytes and animal erythrocytes, including those of sheep, rabbit, horse, and bovine. The hemagglutinating activity of tachylectin-3 was equivalent to that of a previously identified lectin, named tachylectin-2, with affinity for N-acetyl-D-glucosamine or N-acetyl-D-galactosamine. However, the activity of tachylectin-3 was not inhibited by these two N-acetylhexosamines at 100 mM but was inhibited by a blood group A-pentasaccharide at a minimum inhibitory concentration of 0.16 mM. Furthermore, the hemagglutinating activity was strongly inhibited by bacterial S-type lipopolysaccharides (LPSs) from Gram-negative bacteria but not by R-type LPSs lacking O-antigens. One of the most effective S-type LPSs was from Escherichia coli O111:B4, with a minimum inhibitory concentration of 6 ng/ml. These data suggest that tachylectin-3 specifically recognizes Gram-negative bacteria through the unique structural units of O-antigens. Ultracentrifugation analysis revealed that tachylectin-3 is present in dimer in solution. A cDNA coding for tachylectin-3 was isolated from a hemocyte cDNA library. Tachylectin-3 consisted of two repeating sequences, each with a partial sequence similarity to rinderpest virus neuraminidase. Tachylectin-3 and three previously isolated types of tachylectins were all predominantly expressed in hemocytes and released from hemocytes in response to external stimuli. These lectins present at injured sites suggest that they probably serve synergistically to accomplish an effective host defense against invading microbes. 相似文献
184.
Recently, evolutionary robotics (ER) has been attracting a lot of attention in the field of robotics artificial life and so
on. ER approaches are expected to provide feasible methods to design controllers for autonomous mobile robots with less human
intervention. However, most of the conventional studies in ER have been aiming at obtaining very simple (trivial) behaviors
such as obstacle avoiding, wall following, and target approaching. To make the ER approach more fruitful, we should pay close
attention to obtaining nontrivial behaviors. Based on these considerations, in this paper we propose a method for obtaining
nontrivial behaviors using a developmental process with a carefully arranged grafting method. To verify the validity, we apply
our idea to the construction of neural controllers that can cope with rough terrain.
This work was presented, in part, at the Third International Symptosium on Artificial Life and Robotics, Oita, Japan, January
19–21, 1998 相似文献
185.
Current studies on physiological functions of certain plant seed oils containing conjugated trienoic acids as a major fatty acid component are indicative of the possible usefulness of these oils as a new type of functional oils. Here, we describe the potential health benefits of conjugated trienoic acids. 相似文献
186.
Masataka Furuta Toshiaki Shimizu Hiroaki Hayashi Itaru Miyazaki Hiroshi Yamamoto Michihiro Shibata Kiyoshi Kawade 《Annals of Nuclear Energy》2008
Activation cross sections of (n, p) and (n, α) reactions were measured by means of the activation method in the neutron energy range of 3.5–5.9 MeV using a deuterium gas target. The irradiated target isotopes were 27Al, 28,29Si, 41K, 51V, 61Ni, 65Cu, 64,67Zn, 69Ga, 79Br, 92Mo and 93Nb. The cross sections of the 29Si(n, p) 29Al, 67Zn(n, p) 67Cu, 69Ga(n, p) 69mZn, 79Br(n, p) 79mSe, and 69Ga(n, α) 66Cu reactions were obtained for the first time in the studied energy range. The d-D neutrons were generated by the deuterium gas target at the Van de Graaff accelerator (KN-VdG) at Nagoya University. All cross section values were determined relative to those of the 115In(n, n′)115mIn reaction. The activities induced by the low-energy neutrons were corrected. For the corrections, the neutron spectra and mean neutron energies at the irradiation positions were calculated taking into account the energy loss of incident deuterons, the angular differential cross section of the d-D reaction and the solid angle subtended by the sample. The systematics of the (n, p) reactions at the neutron energy of 5.0 MeV in the mass range between 27 and 92 were proposed for the first time. This systematics can predict the cross sections within an accuracy of a factor of 1.6. 相似文献
187.
Iwaki Akiyama 《International journal of imaging systems and technology》1997,8(5):432-437
This article proposes a tomographic reconstruction technique using divergent ultrasonic waves of a circular arc wavefront which are formed by one-dimensional thin-phased array. The projection data which are obtained by phasing of transmitting and receiving signals are applied to the filtered back projection algorithm so that the image at the spherical surface is reconstructed. The experiments using a small steel sphere and a layer phantom of agar gel are performed using a commercially available phased-array system. The divergent waves are formed by the slit in the front of the array. As a result, images with a space-invariant, high-resolution unlike conventional B-scan image are obtained. © 1997 John Wiley & Sons, Inc. Int J Imaging Syst Technol, 8, 432–437, 1997 相似文献
188.
Atsushi Kawase Ouka Takashima Satsuki Tanaka Hiroaki Shimada Masahiro Iwaki 《International journal of molecular sciences》2022,23(15)
Non-steroidal anti-inflammatory drugs (NSAIDs) such as diclofenac (DIC) frequently induce drug-induced liver injury (DILI). It is unclear whether macrophages such as M1 and M2 participate in NSAID-associated DILI; elucidating this relationship could lead to a better understanding of the detailed mechanism of DILI. We co-cultured human hepatoma HepG2 cells with M1 or M2 derived from human monocytic leukemia THP-1 cells to examine the roles of M1 and M2 in DIC-induced cytotoxicity. DIC was added to the direct or indirect co-cultures of HepG2 cells with M1 or M2 (HepG2/M1 or HepG2/M2, respectively) at cell ratios of (1:0, 1:0.1, 1:0.4, and 1:1). In both direct and indirect HepG2/M2 co-cultures (1:0.4), there was lower lactate dehydrogenase release compared with HepG2/M1 co-cultures. Other NSAIDs as well as DIC showed similar protective effects of DIC-induced cytotoxicity. There were only slight differences in mRNA levels of apoptosis- and endoplasmic reticulum stress-associated factors between M1 and M2 after DIC treatment, suggesting that other factors determined the protective effects of M2 on DIC-induced cytotoxicity. Levels of high mobility group box 1 (HMGB1) in the medium and the mRNA expression levels of HMGB1 receptors were different between M1 and M2 after DIC treatment. Increased HMGB1 concentrations and expression of toll-like receptor 2 mRNA in M1 were observed compared with M2 after DIC treatment. In conclusion, these results suggested that the HMGB1/TLR2 signaling axis can be suppressed in M2 but not M1, leading to the different roles of M1 and M2 in NSAID-induced cytotoxicity. 相似文献
189.
Chemical Synthesis of Side-Chain-Hydroxylated Vitamin D3 Derivatives and Their Metabolism by CYP27B1
Ryota Sakamoto Akiko Nagata Haruki Ohshita Yuka Mizumoto Miho Iwaki Dr. Kaori Yasuda Prof. Toshiyuki Sakaki Dr. Kazuo Nagasawa 《Chembiochem : a European journal of chemical biology》2021,22(19):2896-2900
1α,25-Dihydroxyvitamin D3 (abbreviated here as 1,25D3) is a hormonally active form of vitamin D3 (D3), and is produced from D3 by CYP27 A1-mediated hydroxylation at C25, followed by CYP27B1-mediated hydroxylation at C1. Further hydroxylation of 25D3 and 1,25D3 occurs at C23, C24 and C26 to generate corresponding metabolites, except for 1,25R,26D3. Since the capability of CYP27B1 to hydroxylate C1 of side-chain-hydroxylated metabolites other than 23S,25D3 and 24R,25D3 has not been examined, we have here explored the role of CYP27B1 in the C1 hydroxylation of a series of side-chain-hydroxylated D3 derivatives. We found that CYP27B1 hydroxylates the R diastereomers of 24,25D3 and 25,26D3 more effectively than the S diastereomers, but shows almost no activity towards either diastereomer of 23,25D3. This is the first report to show that CYP27B1 metabolizes 25,26D3 to the corresponding 1α-hydroxylated derivative, 1,25,26D3. It will be interesting to examine the physiological relevance of this finding. 相似文献
190.
Futaba Inoue Kenbun Sone Yusuke Toyohara Yu Takahashi Asako Kukita Aki Hara Ayumi Taguchi Michihiro Tanikawa Tetsushi Tsuruga Yutaka Osuga 《International journal of molecular sciences》2021,22(5)
Endometrial cancer is one of the most frequently diagnosed gynecological malignancies worldwide. However, its prognosis in advanced stages is poor, and there are only few available treatment options when it recurs. Epigenetic changes in gene function, such as DNA methylation, histone modification, and non-coding RNA, have been studied for the last two decades. Epigenetic dysregulation is often reported in the development and progression of various cancers. Recently, epigenetic changes in endometrial cancer have also been discussed. In this review, we give the main points of the role of DNA methylation and histone modification in endometrial cancer, the diagnostic tools to determine these modifications, and inhibitors targeting epigenetic regulators that are currently in preclinical studies and clinical trials. 相似文献