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Akira Inaba

Publications and source records attributed to Akira Inaba.

8 recordsLinked to original sources
PubMed2005

Alkane/Alcohol mixed monolayers at the solid/liquid interface.

In this work, we present the behavior of solid monolayers of binary mixtures of alkanes and alcohols adsorbed on the surface of graphite from their liquid mixtures. We demonstrate that solid monolayers form for all the combinations investigated here. Differential scanning calorimetry (DSC) is used to identify the surface phase behavior of these mixtures, and elastic neutron incoherent scattering has been used to determine the composition of the mixed monolayers inferred by the calorimetry. The mixing behavior of the alcohol/alkane monolayer mixtures is compared quantitatively with alkane/alkane and alcohol/alcohol mixtures using a regular solution approach to model the incomplete mixing in the solid monolayer with preferential adsorption determining the surface composition. This analysis indicates the preferential adsorption of alcohols over alkanes of comparable alkyl chain length and even preferential adsorption of shorter alcohols over longer alkanes, which contrasts strongly with mixtures of alkane/alkane and alcohol/alcohol of different alkyl chain lengths where the longer homologue is always found to preferentially adsorb over the shorter. The alcohol/alkane mixtures are all found to phase separate to a significant extent in the adsorbed layer mixtures even when molecules are of a similar size. Again, this contrasts strongly with alkane/alkane and alcohol/alcohol mixtures where, although phase separation is found for molecules of significantly different size, good mixing is found for similar size species.

Journal Article↗
PubMed2005

Unusual Gruneisen and Bridgman parameters of low-density amorphous ice and their implications on pressure induced amorphization.

The low-temperature limiting value of the Grüneisen parameter for low-frequency phonons and the density dependence of the thermal conductivity (Bridgman parameter) of low-density amorphous (LDA) ice, high-density amorphous (HDA) ice, hexagonal ice Ih, and cubic ice Ic were calculated from high-pressure sound velocity and thermal conductivity measurements, yielding negative values for all states except HDA ice. LDA ice is the first amorphous state to exhibit a negative Bridgman parameter, and negative Grüneisen parameters are relatively unusual. Since Ih, Ic, and LDA ice all transform to HDA upon pressurization at low temperatures and share the unusual feature of negative Grüneisen parameters, this seems to be a prerequisite for pressure induced amorphization. We estimate that the Grüneisen parameter increases at the ice Ih to XI transition, and may become positive in ice XI, which indicates that proton-ordered ice XI does not amorphize like ice Ih on pressurization.

Journal Article↗
PubMed2003

Layer-by-layer surface freezing of linear alcohols at the graphite/liquid interface.

Differential scanning calorimetry (DSC), incoherent elastic neutron scattering, and neutron diffraction are used to demonstrate the presence of adsorbed solid multilayers of linear alcohols at the graphite-liquid alcohol interface. All alcohols studied (C(5)-C(18)) are found to form at least one monolayer. In addition all the even alcohols investigated (C(6)OH to C(18)OH) show multilayer formation. However, only the short odd alcohols (C(5)OH to C(11)OH) clearly exhibit additional features indicating multilayer formation.

Journal Article↗
PubMed2003

Glucose hypometabolism in medial frontal cortex of patients with apraxia of lid opening.

PURPOSE: To determine whether regional cerebral functional abnormalities exist in patients with apraxia of lid opening (ALO). METHODS: Cerebral glucose metabolism was examined by positron emission tomography (PET) in 11 patients (8 women and 3 men, age 48-69 years); 10 with ALO accompanied by blepharospasm and 1 patient with pure ALO. Eleven normal volunteers (6 women and 5 men, age 45-66 years) were examined as controls. A comprehensive ophthalmological examination, magnetic resonance imaging (MRI), and PET were performed. The cerebral glucose metabolism was evaluated by the relative uptake of [fluorine-18]fluorodeoxyglucose by PET. The mean +/- two standard deviations of the normal controls was defined as the normal range for cerebral glucose metabolism. RESULTS: MRI revealed no particular lesion except for an infarction in the unilateral basal ganglia in two patients. Decreased glucose metabolism was observed in a wide area of the medial frontal lobe (six cases) and primary visual cortex (PVC) (four cases). Group multiple comparisons revealed a significant decrease ( P<0.0035) in the bilateral anterior cingulate gyrus, left supplementary motor area (SMA), and bilateral PVC. CONCLUSION: The results support the hypothesis that ALO is associated with hypofunction in the SMA and/or anterior cingulate gyrus.

Aged↗
PubMed2003

Construction of gene expression system in hop (Humulus lupulus) lupulin gland using valerophenone synthase promoter.

The promoter region of the valerophenone synthase (VPS) gene was isolated from hop (Humulus lupulus). VPS, a member of the chalcone synthase (CHS) super-family, catalyzes the biosynthesis reaction of the hop resin that significantly accumulates in the cone's secretory gland called the "lupulin gland". The typical H-box and G-box sequences, which exist in many plants' CHS promoters and act as cis-elements for tissue specificity, UV-light induction, etc., were not found in the isolated VPS promoter, although the H-box-like sequence (CCTTACC, CCTAACC) and the core sequence (ACGT) of the G-box were observed. The transformation experiment using the VPS promoter-UIDA gene fusion revealed that the promoter acts not only in the lupulin gland but also in the glands of leaf and stem. On the other hand, the VPS promoter activity was not induced by UV-irradiation.

Acyltransferases↗
PubMed2003

[Two distinct types of neuropathy associated with Sjögren's syndrome developed in one patient. The importance of the selection of an appropriate therapeutic regimen].

A 62-year-old woman was admitted to our hospital because of muscle weakness and sensory disturbance in extremities. She showed weakness, muscle atrophy and sensory abnormality in four limbs with patchy distribution, suggesting involvement of multiple peripheral nerve trunks. Serum titers of anti-SS-A, SS-B, and antinuclear antibody were elevated. Sural nerve biopsy showed recanalization and lymphocytic infiltration in the epineural small vessels, suggesting the presence of vasculitis. She was diagnosed as having vasculitic neuropathy complicated with Sjögren's syndrome. Methylprednisolone pulse therapy followed by oral prednisolone was started and these symptoms gradually improved in one month. At age 63, she felt dysesthesia in the right lower limb and this sensory abnormality spreaded to upper limbs. Two years later, she was admitted again due to clumsiness of hands and gait disturbance. Neurological examination showed decreased vibration and position sense of lower limbs and limb ataxia in addition to dysesthesia. Electrophysiological studies demonstrated significant decrease in amplitude of sensory nerve action potentials and delayed somatosensory evoked potentials after N13, indicating impairment of dorsal root ganglions. She was treated with intravenous immunoglobulin (400 mg/kg, total 15 g/day) for 5 days. One week later, sensory ataxia was improved. It has been known that Sjögren's syndrome is often complicate with various types of neuropathies including vasculitic neuropathy and sensory neuropathy. Our patient developed these two different types of neuropathies which were dramatically improved after two different therapeutic regimens; indicating the importance to select a suitable treatment regimen in accordance with the mechanism of neuropathy associated with Sjögren's syndrome.

Adrenal Cortex Hormones↗
PubMed2002

Electrophysiological evaluation of conduction in the most proximal motor root segment.

Root conduction time (RCT), defined as the time difference between M-wave latency by cervical magnetic stimulation (CMS) and the total peripheral motor conduction time calculated from the shortest F-wave latency, was investigated in patients with inflammatory demyelinating neuropathies (IDP) and amyotrophic lateral sclerosis (ALS). The minimal threshold for CMS also was studied. In the IDP patients, conduction in the proximal motor root segment was considered abnormal in 52% by the RCT and in 47% by the minimal threshold for CMS, whereas both were normal in 85% of the ALS patients. These findings suggest that the RCT and minimal threshold for CMS might be additional parameters for evaluating motor nerve conduction in IDP.

Action Potentials↗