Proposal of mechanics of liquid crystals and development of liquid crystalline microactuators

We propose a research field “mechanics of liquid crystals,” in which liquid crystals are studied from a mechanical viewpoint. The unsteady behaviors of a liquid crystal between parallel plates under an electric field are investigated. The imposition of the electric field on the liquid crystal induces flows, whose profile and magnitude strongly depend on the twist angle of the director at the plates. A visualization experiment confirms the generation of flows. The mechanism of such generation can be explained by considering that the rotation of molecules generated by the imposition of the electric field induces a local velocity gradient

Molecular dynamics simulation of backflow generation in nematic liquid crystals

The mechanism of backflow generation in nematic liquid crystals under the application of an electric field is investigated by molecular dynamics simulation, and the roles of intermolecular interaction in the generation of bulk velocity are investigated. It is confirmed that the reorientation of molecules by the application of an electromagnetic field induces a transient “S-shaped” bulk velocity profile. The rotation and rearrangement of molecules during the reorientation process generate a local bulk velocity gradient

原子層物質における非平衡量子現象とトポロジカル超伝導

京都大学新制・課程博士博士(理学)甲第22988号理博第4665号新制||理||1669(附属図書館)京都大学大学院理学研究科物理学・宇宙物理学専攻(主査)教授 柳瀬 陽一, 教授 田中 耕一郎, 教授 石田 憲二学位規則第4条第1項該当Doctor of ScienceKyoto UniversityDFA

On the use of dexamethasone-loaded liposomes to induce the osteogenic differentiation of human mesenchymal stem cells

Article first published online: 7 Oct. 2013Stem cells have received considerable attention by the scientific community because of their potential for tissue engineering and regenerative medicine. The most frequently used method to promote their differentiation is supplementation of the in vitro culture medium with growth/differentiation factors (GDFs). The limitations of that strategy caused by the short half-life of GDFs limit its efficacy in vivo and consequently its clinical use. Thus, the development of new concepts that enable the bioactivity and bioavailability of GDFs to be protected, both in vitro and in vivo, is very relevant. Nanoparticle-based drug delivery systems can be injected, protect the GDFs and enable spatiotemporal release kinetics to be controlled. Liposomes are well-established nanodelivery devices presenting significant advantages, viz. a high load-carrying capacity, relative safety and easy production, and a versatile nature in terms of possible formulations and surface functionalization. The main objective of the present study was to optimize the formulation of liposomes to encapsulate dexamethasone (Dex). Our results showed that the optimized Dex-loaded liposomes do not have any cytotoxic effect on human bone marrow-derived mesenchymal stem cells (hBMSCs). More importantly, they were able to promote an earlier induction of differentiation of hBMSCs into the osteogenic lineage, as demonstrated by the expression of osteoblastic markers, both phenotypically and genotypically. We concluded that Dex-loaded liposomes represent a viable nanoparticle strategy with enhanced safety and efficacy for tissue engineering and regenerative medicine.The authors thank the Portuguese Foundation for Science and Technology for a PhD grant (No. SFRH/BD/62465/2009, to N. S. Monteiro). This work was partly supported by the FIND and BIND Project (No. NMP4-SL-2009-229292) and the OsteoGraphy Project (No. PTDC/EME-MFE/2008)

Two-qubit gate using conditional driving for highly detuned Kerr-nonlinear parametric oscillators

A Kerr-nonlinear parametric oscillator (KPO) is one of the promising devices to realize qubits for universal quantum computing. The KPO can stabilize two coherent states with opposite phases, yielding a quantum superposition called a Schr\"{o}dinger cat state. Universal quantum computing with KPOs requires three kinds of quantum gates: $R_z, R_x$, and $R_{zz}$ gates. We theoretically propose a two-qubit gate $R_{zz}$ for highly detuned KPOs. In the proposed scheme, we add another two-photon drive for the first KPO. This leads to the $R_{zz}$ gate based on the driving of the second KPO depending on the first-KPO state, which we call "conditional driving." First, we perform simulations using a conventional KPO Hamiltonian derived from a superconducting-circuit model under some approximations and evaluate the gate fidelity. Next, we also perform numerical simulations of the two-qubit gate using the superconducting-circuit model without the approximations. The simulation results indicate that two-qubit gates can be implemented with high fidelity ($>99.9\%$) for rotation angles required for universality.Comment: 9 pages, 7 figure

Mapping QTLs for grain dormancy on wheat chromosome 3A and the group 4 chromosomes, and their combined effect

application/pdfA major QTL for grain dormancy, QPhs.ocs-3A.1, derived from the highly dormant wheat Zenkoujikomugi (Zen), has been identified in a study made under a controlled environment. Further investigations were needed to dissect the precise position and expression of QPhs.ocs-3A.1 under different field conditions because the ability to detect genetic loci for grain dormancy traits is compromised by environmental effects and genotype/environment interactions. Group 4 chromosomes have also been shown to be possible sites of QTLs for grain dormancy. The objectives of this study were (1) to locate additional molecular markers in the QPhs.ocs-3A.1 region, (2) to identify QTLs on the group 4 chromosomes and (3) to elucidate their combined effects. We examined the recombinant inbred lines (RILs) from a cross between Chinese Spring (CS) and Zen over a 3-year period in one location and 1 year in a different location. In an interval mapping study QPhs.ocs-3A.1 was mapped to within the 4.6 cM region flanked by Xbarc310 and Xbcd907 at the proximal end of the short arm of chromosome 3A. QPhs.ocs-3A.1 was confirmed to be the predominant dormancy QTL since it explained a large portion (11.6-44.8%) of the phenotypic variation, and was strongly displayed under dormancy-breaking conditions or at low germination temperatures. For QPhs.ocs-4A.1, identified on the long arm of chromosome 4A, and QPhs.ocs-4B.1, on the centromeric region of the long arm of Chr 4B, the LOD peak positions and the desirable allele were consistent between the trials, while the LOD scores and contribution to the phenotypic variation varied. Transgressive segregants were observed among the 125 RILs and most of them had a combination of the three alleles conferring a higher dormancy: the Zen alleles at QPhs.ocs-3A.1 and QPhs.ocs-4A.1 and the CS allele at QPhs.ocs-4B1. This demonstrated a combined effect of the desirable alleles on accelerating grain dormancy, with their total effect being superior to that of Zen.journal articl

FACILE AND SENSITIVE HPLC-UV METHOD FOR DETERMINATION OF NINTEDANIB IN RAT PLASMA

Objective: In this study, a facile and sensitive high-performance liquid chromatographic method for determination of nintedanib in rat plasma was developed and validated.Methods: After plasma protein was precipitated by addition of acetonitrile, the supernatant underwent centrifugation. An aliquot was then injected into a high-performance liquid chromatographic system with a Mightysil RP-18 GP II ODS column (250 × 3.0 mm, length by inner diameter, 5-μm particle size) maintained at 50 °C. A mobile phase mixture of 20 mmol phosphate buffer (pH 3.0) and acetonitrile (7:3, v/v) was used at a flow rate of 0.6 mL/min, with UV detection at a wavelength of 390 nm for isocratic separation and detection of nintedanib, its main metabolite (BIBF1202), and p-nitrophenol as an internal standard.Results: The quantitative range of nintedanib concentration in this method was 12.5–400 ng/ml, and the calibration curves were linear. The intra-and inter-day accuracy values (relative errors) were in the range of −3.65%–4.00% and −3.65%–3.64%, respectively. The intra-and inter-day precision values (relative standard deviations) were<5.9% and 8.36%, respectively. The method was successfully applied to a pharmacokinetic analysis of nintedanib in rats after intravenous administration.Conclusion: In this study, a rapid, sensitive, and simple HPLC-UV method for the quantitation of nintedanib in rat plasma was developed and validated. The method was shown to be accurate and precise and was successfully applied to a pharmacokinetic study

Clinical and Parasitological Effects of Aspilia africana (Pers.) C.D. Adams in Fifteen Patients with Uncomplicated Malaria

This paper reports the findings of a clinical study of a herbal preparation of Aspilia africana (Pers.) C.D. Adams against malaria, corroborated by in vitro antiplasmodial and cytotoxicity tests. In a non-controlled prospective design, 15 patients with uncomplicated malaria were administered with the herbal preparation and assessed for clinical manifestations of malaria, parasitaemia and global quality of life using the Kanorfsky Performance Scale. Antiplasmodial activity of extracts against the chloroquine-resistant strain of Plasmodium falciparum Dd2 was determined using the [3H]-hypoxanthine radioactive method while cytotoxicity against human urinary bladder carcinoma (ECV-304) and human hepatocellular carcinoma (HepG2) cell lines was determined using the MTT assay. Remarkable clinical improvements occurred 3 to 21 days after initiation of treatment. Forty nine days after starting treatment, all 15 patients had complete resolution of malaria symptoms and were cleared of parasitaemia and attained a Karnofsky Performance score of 100. The petroleum ether/ethyl acetate extract possessed in vitro antiplasmodial activity (IC50 30μg/ml) but no remarkable cytotoxicity. The A. africana preparation shows potential as an alternative for the management of uncomplicated malaria.East and Central African Journal of Pharmaceutical Sciences Vol. 12 (2009) 37-4