Control of multi-joint arm movements for the manipulation of touch in keystroke by expert pianists

Background  

Production of a variety of finger-key touches in the piano is essential for expressive musical performance. However, it remains unknown how expert pianists control multi-joint finger and arm movements for manipulating the touch. The present study investigated differences in kinematics and kinetics of the upper-limb movements while expert pianists were depressing a key with two different touches: pressed and struck. The former starts key-depression with the finger-tip contacting the key, whereas the latter involves preparatory arm-lift before striking the key. To determine the effect of individual muscular torque (MUS) as well as non-muscular torques on joint acceleration, we performed a series of inverse and forward dynamics computations.     

Formation of mono(8-hydroxyquinoline) lithium(I) complex in smectites by solid-solid reactions

Lithium quinolate including mono(8-hydroxyquinoline) lithium(I) complex (Liq) formed in the interlayer spaces of two smectites via solid-solid reactions and in situ complex formation by reacting Li-smectites (Li(I)-synthetic saponite and Li(I)-montmorillonite) with 8-hydroxyquinoline at room temperature. The incorporation of 8-hydroxyquinoline into Li(I)-smectites was proved by powder X-ray diffraction, infrared spectroscopy, thermal and elemental (CHN) analysis. UV-vis absorption and photoluminescence spectra indicated that 8-hydroxyquinoline ligand formed Liq chelate in the interlayer spaces of smectites. The higher luminescence intensity of the Liq complex in synthetic saponite confirmed the very low content of quenching impurities such as iron in the synthetic saponite. The variation of the photoluminescence bands supported the difference in molecular packing and/or crystal structure of the complex formed in the interlayer spaces of smectites.     

Thermal behaviour of the thermotropic cubic mesogen 4'-n-hexadecyloxy-3'-nitrobiphenyl-4-carboxylic acid (ANBC-16) under hydrostatic pressure

The phase behaviour of 4'-n-hexadecyloxy-3'-nitrobiphenyl-4-carboxylic acid (ANBC-16) was investigated under hydrostatic pressures up to 200 MPa using high pressure differential thermal analysis. The phase transition sequence crystal 4 (Cr4)-crystal 3 (Cr3)-crystal 2 (Cr₂)-crystal 1 (Cr₁)-smectic C (SmC)-Cubic (Cub)-smectic A (SmA)-'structured liquid' (I₁)-isotropic liquid (I₂) was observed for a virgin sample on heating at atmospheric pressure. The stable temperature region of the optically isotropic cubic phase becomes narrower on increasing pressure and disappears at pressures above 65 MPa. The T vs. P phase diagram exhibits the existence of a triple point (65 MPa, 207.6°C) for the cubic phase, a new mesophase (X), and the SmA phase, indicating the upper limit for the cubic phase. The new mesophase, denoted here as X, appears in place of the cubic phase at pressures above 65 MPa. The phase diagram also indicates that the Cr₄-Cr₃, Cr₃-Cr₂, and Cr₂-Cr₁ transition lines merge at about 40-50 MPa and then only the Cr₄-Cr₁ transition is observed in the solid state at higher pressures. Thus the phase transition process on heating changes from the sequence Cr₄-Cr₃-Cr₂-Cr₁-SmC-Cub-SmA-I₁-I₂ at atmospheric pressure to Cr₄-Cr₁-SmC-X-SmA-I₁-I₂ in the high pressure region above 65 MPa, via Cr₄-Cr₃-Cr₂-Cr₁-SmC-(X)-Cub-SmA-I₁-I₂ in the low pressure region.     

Two routes to polycrystalline CoSi2 thin films by co-sputtering Co and Si

Two processes for the fabrication of polycrystalline CoSi₂ thin films based on the codeposition of Co and Si by sputtering were studied and compared. The first process involved “annealing after deposition”, where Co and Si are codeposited at ambient temperature and then crystallized by annealing. This process yielded randomly oriented plate-like CoSi₂ grains with a grain size that is governed by the nanostructure of the as-deposited film. Polycrystalline CoSi₂ thin films were obtained at a process temperature of 170 °C, which was much lower than the annealing temperature of 500 °C needed for Co/Si bilayers. The second process involved “heating during deposition”, where Co and Si are codeposited on heated substrates. This process yielded CoSi₂ grains with a columnar structure, and the grain size and degree of (1 1 1) orientation are temperature dependent. The sheet resistance of the resulting films was determined by the preparation temperature regardless of the deposition process used, i.e. “annealing after deposition” or “heating during deposition”. Temperatures of 500 °C and higher were needed to achieve CoSi₂ resistivity of 40 μΩ cm or lower for both processes.     

Nature of copper(II)-lanthanide(III) magnetic interactions and generation of a large magnetic moment with magnetic anisotropy of 3d-4f cyclic cylindrical tetranuclear complexes [CuIILLnIII(hfac)2]2, (H3L = 1-(2-hydroxybenzamido)-2-(2-hydroxy-3-methoxybenzylideneamino)ethane and Hhfac = hexafluoroacetylacetone,LnIII = Eu,Gd, Tb,Dy)

A cyclic cylindrical 3d-4f tetranuclear structure, in which the 3d and 4f magnetic ions are arrayed alternately, has been found to be a suitable molecular design to produce a large magnetic moment and large magnetic anisotropy. Complexes 3-10 with the chemical formula [MLLn(hfac)2]2 ((MII, LnIII) = (Cu, Eu) (3), (Cu, Gd) (4), (Cu, Tb) (5), (Cu, Dy) (6), (Ni, Eu) (7), (Ni, Gd) (8), (Ni, Tb) (9), (Ni, Dy) (10)) have been synthesized, where H3L = 1-(2-hydroxybenzamido)-2-(2-hydroxy-3-methoxybenzylideneamino)ethane and Hhfac = hexafluoroacetylacetone. The powder X-ray diffractions and FAB-mass spectra demonstrated that these complexes assume a similar tetranuclear structure. The crystal structures of 4 and 5 showed that each complex has a cyclic cylindrical tetranuclear CuII2LnIII2 structure, in which the CuII complex functions as a "bridging ligand-complex" to two adjacent LnIII ions. The temperature-dependent magnetic susceptibilities from 2 to 300 K and the field-dependent magnetizations at 2 K from 0 to 5 T have been measured for four pairs of CuII2LnIII2 and NiII2LnIII2, in which compound NiII2LnIII2 containing diamagnetic NiII ion was used as the reference complex to evaluate the CuII-LnIII magnetic interaction. Comparison of the magnetic properties of the CuII2LnIII2 complex with those of the corresponding NiII2LnIII2 complex showed that the magnetic interaction between CuII and EuIII ions is weakly ferromagnetic and that between CuII and either of GdIII, TbIII, and DyIII ions is ferromagnetic. Complex CuII2GdIII2, 4, has an S = 8 spin ground state, due to the ferromagnetic spin coupling between SGd = 7/2 and SCu = 1/2 with coupling constants of J1 = +3.1 cm-1 and J2 = +1.2 cm-1. The magnetic measurements showed that compounds 5 and 6, CuII2LnIII2 (LnIII = Tb, Dy), exhibit large magnetic moments and large magnetic anisotropy due to the LnIII ion.     

Preparation and some properties of organically modified layered alkali titanates with alkylmethoxysilanes

The silylation of K2Ti4O9 x nH2O with organosilanes (methyl, n-butyl, n-octyl, n-dodecyl, n-octadecyltrimethoxysilanes and n-octadecyldimethylmethoxysilane) was conducted using the octylammonium-exchanged form as the intermediate. The surface coverage of the octadecylsilylated derivative was controlled by changing the employing amounts of octadecyltrimethoxysilane. The swelling behaviors of the octyl, dodecyl, and octadecylsilylated derivatives in organic solvents were investigated to show that the degree of the swelling varies depending on the kind of solvents, the alkyl chain length of the attached alkylsilyl groups, and the surface coverage. The octadecylsilylated derivative with the largest surface coverage was converted to film with a thickness of ca. 500 nm by casting the chloroform suspension on a substrate. The octadecylsilylated derivative showed a reversible thermoresponsive change of the basal spacing by ca. 0.5 nm in the temperature range between 15 and 60 degrees C.     

Intermediate as catalyst: catalytic asymmetric conjugate addition of nitroalkanes to α,β-unsaturated thioamides

Catalytic asymmetric conjugate addition of nitroalkanes to α,β-unsaturated thioamides is promoted by a mesitylcopper/(R)-DTBM-Segphos precatalyst, affording γ-nitrothioamides in moderate to high syn-selectivity and excellent enantioselectivity. The intermediate Cu-thioamide enolate functions as a soft Lewis acid/hard Br?nsted base cooperative catalyst to drive the catalytic cycle efficiently under proton transfer conditions.     

Selective trifluorination of alkyl aryl sulfides using IF5

In the reaction of IF₅ with alkyl aryl sulfides in heptane under reflux conditions, the arylthio group migrated once and three fluorine atoms were selectively introduced on the alkyl chain. In order to find the reason why the reaction stopped at the trifluorination step, we examined the oxidation potentials of the starting material, a reaction intermediate, and the product, and the time course of the reactions.     

Lewis acid-catalyzed tri- and difluoromethylation reactions of aldehydes

The first Lewis acid-catalyzed trifluoromethylation reactions of aldehydes with Me3SiCF3 under TiF4/DMF, Ti(O iPr)4/DMF and Cu(OAc)2/dppp/toluene conditions are described. We have successfully applied this methodology to the difluoromethylation of aldehydes using Me3SiCF2SePh, Me3SiCF2P(O)OEt2 and Me3SiCF2SPh.     

Development of a flow-injection analysis (FIA) enzyme sensor for fructosyl amine monitoring

An enzyme-sensor system with flow-injection analysis (FIA) has been developed for the detection of fructosyl amine compounds; the sensor utilizes fructosyl amine oxidase isolated from the marine yeast Pichia sp. N1-1 strain. With this FIA system 0.2 to 10 mmol L(-1) fructosyl valine can be determined. The sensor is approximately five times more sensitive to fructosyl valine, a model compound for glycated hemoglobin HbA1c, than to N(epsilon)-fructosyl lysine, a model compound for glycated albumin. This FIA system can also be used to detect fructosyl dipeptides. The operational stability of the sensor enabled more than 120 consecutive sample injections over a period of approximately 20 h.