102 research outputs found
Notes on the Hamiltonian formulation of 3D Yang-Mills theory
Three-dimensional Yang-Mills theory is investigated in the Hamiltonian
formalism based on the Karabali-Nair variable. A new algorithm is developed to
obtain the renormalized Hamiltonian by identifying local counterterms in
Lagrangian with the use of fictitious holomorphic symmetry existing in the
framework with the KN variable. Our algorithm is totally algebraic and enables
one to calculate the ground state wave functional recursively in gauge
potentials. In particular, the Gaussian part thus calculated is shown to
coincide with that obtained by Leigh et al. Higher-order corrections to the
Gaussian part are also discussed.Comment: 26 pages, LaTeX; discussions on IR regulators and local counterterms
improved, references adde
The development of “Ultimate Rudder” for EEDI
EEDI (Energy Efficiency Design Index) came into effect mandatory in Jan.
2013, and the ship owners definitely required a higher efficiency propulsion system than ever
before. Hence, the shipyards have been conducting an optimization of ESD (Energy Saving Device)
system in self-propulsion test for each project. As the results, the shipyards have
installed a rudder bulb as an effective ESD.
The rudder bulb is a popular ESD system from a long time ago. Mewis1) described that the rudder
bulb was developed by Costa in 1952 and the efficiency improve by the rudder bulb for a container
vessel was 1% on average. Fujii et al.2) developed “MIPB (Mitsui Integrated Propeller Boss)” as an
advanced rudder bulb. The feature of MIPB was a streamlined profile from propeller cap to rudder.
According to their paper, the efficiency improve by installing MIPB was 2-4%.
Recently, NAKASHIMA PROPELLER Co., Ltd. developed ECO-Cap (economical propeller
cap)3) as a new ESD with FRP (Fiber Reinforced Plastics). The strength of FRP is higher than that
of NAB (Nickel Aluminium Bronze), therefore ECO-Cap was able to adopt thin fins on propeller
caps for low resistance. Although the material used for the energy- saving propeller cap
was generally NAB, the research results on FRP showed that FRP could be used as ESD due to their
properties such as lightweight and flexibility.
As explained above, the authors thought that there was a possibility to evolve the rudder bulb
profile using the easily moldable FRP compared with NAB. This paper described about the development
of “Ultimate Rudder” of new design concept by FRP. The authors optimized the profile of “Ultimate
Rudder” by CFD and confirmed the efficiency increase from 4.9 to
5.4% in self-propulsion test
Study on the rudder characteristics of ultimate rudder by numerical calculation
The authors invented Ultimate Rudder3) as the rudder with bulb. The authors
calculated the rudder characteristics of the normal rudder and Ultimate Rudder by CFD
at several steering angles and compared these values. The result showed that regardless of the
presence or absence of the bulb, signs of separation appear on the control surface
with a steering angle of 20 deg. to 30 deg. and regarding the steering torque coefficient, it was
found that the steering torque coefficient of Ultimate Rudder is larger than the normal Rudder when
the steering angle is less than 20 deg. and also the steering torque coefficient can be decreased
by changing the shape of the rudder bulb
Functional expression of thiocyanate hydrolase is promoted by its activator protein, P15K
AbstractThiocyanate hydrolase (SCNase) is a cobalt-containing enzyme with a post-translationally modified cysteine ligand, γCys131-SO2H. When the SCNase α, β and γ subunits were expressed in Escherichia coli, the subunits assembled to form a hetero-dodecamer, (αβγ)4, like native SCNase but exhibited no catalytic activity. Metal analysis indicated that SCNase was expressed as an apo-form irrespective of the presence of cobalt in the medium. On the contrary, SCNase co-expressed with P15K, encoded just downstream of SCNase genes, in cobalt-enriched medium under the optimized condition (SCNase(+P15K)) possessed 0.86 Co atom/αβγ trimer and exhibited 78% of the activity of native SCNase. SCNase(+P15K) showed a UV–Vis absorption peak characteristic of the SCNase cobalt center. About 70% of SCNase(+P15K) had the γCys131-SO2H modification. These results indicate that SCNase(+P15K) is the active holo-SCNase. P15K is likely to promote the functional expression of SCNase probably by assisting the incorporation of cobalt ion
A Novel Reagent for the Synthesis of Branched-chain Functionalized Sugars. Dichloromethyllithium
A few novel branched-chain functionalized sugars, which have important functions such as hydroxyl, hydro, chloro, or azido at quaternary carbon were prepared in good yield via the same intermediary spiro chloroepoxide derivative by use of dichloromethyllithium
Expression of human mutant cyclin dependent kinase 4, Cyclin D and telomerase extends the life span but does not immortalize fibroblasts derived from loggerhead sea turtle (Caretta caretta)
Conservation of the genetic resources of endangered animals is crucial for future generations. The loggerhead sea turtle (Caretta caretta) is a critically endangered species, because of human hunting, hybridisation with other sea turtle species, and infectious diseases. In the present study, we established primary fibroblast cell lines from the loggerhead sea turtle, and showed its species specific chromosome number is 2n = 56, which is identical to that of the hawksbill and olive ridley sea turtles. We first showed that intensive hybridization among multiple sea turtle species caused due to the identical chromosome number, which allows existence of stable hybridization among the multiple sea turtle species. Expressions of human-derived mutant Cyclin-dependent kinase 4 (CDK4) and Cyclin D dramatically extended the cell culture period, when it was compared with the cell culture period of wild type cells. The recombinant fibroblast cell lines maintained the normal chromosome condition and morphology, indicating that, at the G1/S phase, the machinery to control the cellular proliferation is evolutionally conserved among various vertebrates. To our knowledge, this study is the first to demonstrate the functional conservation to overcome the negative feedback system to limit the turn over of the cell cycle between mammalian and reptiles. Our cell culture method will enable the sharing of cells from critically endangered animals as research materials
The Synthetic Curcumin Analogue GO-Y030 Effectively Suppresses the Development of Pressure Overload-induced Heart Failure in Mice
Curcumin is a naturally occurring p300-histone acetyltransferase (p300-HAT) inhibitor that suppresses cardiomyocyte hypertrophy and the development of heart failure in experimental animal models. To enhance the therapeutic potential of curcumin against heart failure, we produced a series of synthetic curcumin analogues and investigated their inhibitory activity against p300-HAT. The compound with the strongest activity was further evaluated to determine its effects on cardiomyocyte hypertrophy and pressure overload-induced heart failure in mice. We synthesised five synthetic curcumin analogues and found that a compound we have named GO-Y030 most strongly inhibited p300-HAT activity. Furthermore, 1 μM GO-Y030, in a manner equivalent to 10 µM curcumin, suppressed phenylephrine-induced hypertrophic responses in cultured cardiomyocytes. In mice undergoing transverse aortic constriction surgery, administration of GO-Y030 at a mere 1% of an equivalently-effective dose of curcumin significantly attenuated cardiac hypertrophy and systolic dysfunction. In addition, this low dose of GO-Y030 almost completely blocked histone H3K9 acetylation and eliminated left ventricular fibrosis. A low dose of the synthetic curcumin analogue GO-Y030 effectively inhibits p300-HAT activity and markedly suppresses the development of heart failure in mice
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