Temperature Dependence of the Raman Spectrum in Lithium Oxide Single Crystal

Temperature dependence of the Raman spectrum of lithium oxide single crystal has been measured over a temperature range of 80 to 1073 K. The frequency shift and the line width of the Raman spectrum in lithium oxide were about 531 and 4.5 cm^-1 at 80 K, respectively. At 1073 K, the frequency shift and the line width attained the values of 464 and 112 cm^-1, respectively. The strong temperature dependence of the frequency shift and line width was compared with data from some crystals with a fluorite structure.     

REM sleep deprivation potentiates the effects of imipramine and desipramine but not that of clomipramine in the forced swimming test

The human amnestic syndrome associated with lesions of the hippocampus and amygdala is characterized by a selective impairment of recent (explicit, episodic) memory. Benzodiazepine (BZ) treated normal subjects demonstrate similar, marked impairments in episodic memory, but in addition, BZ also induces sedation and inattention. Thus, the amnestic effects of BZ may be secondary to drug-induced sedation. However, when subjects were pretreated with the specific BZ receptor antagonist, flumazenil, the sedative and attentional effects of diazepam were blocked, but a marked impairment in episodic memory still occurred. This demonstrates that, using neuropharmacological methods, it is possible to produce a dissociation of memory impairment from inattention and sedation. Such distinct patterns of cognitive dysfunction may serve as models for clinical cognitive syndromes.     

Effective sludge solubilization treatment by simultaneous use of ultrasonic and electrochemical processes.

Sludge disintegration treatment by using simultaneously ultrasonic irradiation and electrolysis was investigated experimentally. A lab-scale diaphragm cell irradiated with ultrasound at a constant oscillating frequency of 20 kHz was used as a reactor. The batch experiments were carried out under different conditions of electric outputs of the ultrasonic generator, electric current for the electrolysis and different initial SS concentrations. A simultaneous treatment in the cathodic compartment without any chemical doses considerably facilitated the sludge solubilization, compared to the sonication alone. An increase in the electric current up to 400 mA under a constant ultrasonic density decreased the specific energy by 55% within the experimental range. The specific energy consumption was also reduced when the initial SS concentration increased. In addition, before carrying out the simultaneous treatment, a brief electrolysis was effective for further reduction of the specific energy and the acceleration of soluble COD generation.     

Changes in the thermomechanical behavior of epoxy glasses under the state of strain aging

Changes in thermomechanical behavior with structural relaxation taking place in epoxy glasses were studied. Differential scanning calorimetry measurements and thermostimulated strain recovery tests were performed for specimens deformed and then aged under fixed strain. In the course of heating, the specimens started to absorb thermal energy, whereas plastic strain was still stable. At higher temperatures, plastic strain started recovery, which was accompanied by exothermic behavior of the specimen. With an increase in the aging duration, the endothermic peak signified and moved to a higher temperature. These results indicated that the longer the aging duration was, the harder the plastic strain and strain energy were frozen in the glassy structure. This freeze‐strain phenomenon was observed for crosslinked epoxy glass, as well as polymeric glasses with linear molecular structures, aged under strain. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Roles of the JAK-STAT system in signal transduction via cytokine receptors

JAK-STAT signaling pathways are known to play an essential role in the specific activation of interferon-inducible genes. Many cytokines interacting with the cytokine receptor superfamily also appear to activate these pathways. Recent evidence indicates that JAKs play an essential role(s) in cytokine receptor signaling, including both specific pathways linked to STATs and general pathways regulating cell growth and functions.     

Surgical treatment of ventricular tachycardia after surgical repair of tetralogy of Fallot. Relation between intraoperative mapping and histological findings

BACKGROUND: The mechanism of ventricular tachycardia (VT) after correction of tetralogy of Fallot (TF) is poorly understood. The purpose of this study was to examine the histopathology of the arrhythmogenic area detected by intraoperative mapping. METHODS AND RESULTS: The patients were three men who underwent radical surgery for TF at age 3, 3, or 5 years, respectively. VT developed at 8, 9, or 11 years, respectively, after surgery, and shock developed during VT in every case. The ECG revealed monomorphic VT in two cases and polymorphic VT in one case. Induction of VT resulted in a wide left-axis deviation-pattern QRS with cycle lengths varying between 260 and 330 milliseconds. The VT origin was identified at the right ventricular outflow tract (RVOT). A radical operation was performed with the patient under cardiopulmonary bypass. On epicardial mapping, delayed activation of the RVOT was recorded during sinus rhythm, and clockwise circus movement of the macroreentry current during VT on the right ventricular free wall was documented in each case. The VTs were treated successfully by surgical resection and cryoablation of the myocardium. In every patient, histology of the myocardial specimens showed degeneration, adiposis, fibrosis, inflammatory cell infiltration, and scattered myocyte islets. These lesions corresponded anatomically to the area of myocardium in which delayed activation was evident during epicardial mapping. CONCLUSIONS: The results of this study indicate that patients with VT after radical correction of the TF have abnormal histopathological findings at the site of the prior right ventriculotomy scar. These lesions were noted within the region of delayed activation found during epicardial mapping and were found to be a part of the reentrant circuit.     

X-ray Photoelectron Spectroscopy Investigation on the Low-Temperature Degradation of 2 mol% Y2O3-ZrO2 Ceramics

2 mol% Y₂O₃-ZrO₂ polycrystals were annealed in water and under vacuum to highlight the effect of the presence of H₂O on the low-temperature degradation transformation. The specimen surfaces with monoclinic phases transformed during annealing in the different environments were analyzed by X-ray photoelectron spectroscopy with special interest on the electron binding energy change of the constituent ions of the 2 mol% Y₂O₃-ZrO₂ ceramics after the degradation transformation. It was found that no change occurred for the electron-bonding energies of core levels of zirconium ions after the transformation, whereas Y-OH bonds were formed during annealing in water. This result suggested a possibility that the preferred hydration of yttrium took place at the surface of Y₂O₃-partially-stabilized ZrO₂, which is likely to be the reason for the low-temperature degradation accelerated by the presence of H₂O.     

Cloning, functional expression and tissue distribution of rabbit alpha 1d-adrenoceptor

We attempt to determine the utility of CERAD in detecting early Alzheimer's disease (AD). CERAD battery was administered to a group of 14 control subjects, 12 patients with possible dementia prodromes and to patients with Alzheimer's disease stratified according to severity (16 mild, 8 moderate). Other measures as some subtest of the Wechsler memory scale and the Rey Complex Figure Test were also applied. Delayed recall as well as logical memory of Wechsler memory scale were found to be the best discriminators for detecting very mild cases of AD (Prodromes) (p < 0.05). None of the memory test proved of value in staging the disorder. Visuospatial functions are better determinants of the progression of the illness. Fluency also distinguish between control subjects and very mild cases. These findings suggest that delayed recall memory and probably executive function are the most useful and sensitive indicators of Alzheimer's disease.     

A novel technique for a DC brushless motor without position sensors

A dc brushless motor is a kind of synchronous motor driven by an inverter and requires sensors to detect the rotor position. As one of the methods, the induced voltages of a brushless motor have been utilized in practice. However, there are some problems in this method, e.g., the motor can obtain insufficient torque due to the low induced voltages in a low-speed range. This paper proposes a new method which controls the inverter angular frequency ω₁ by using inherent characteristics wherein the torque current i_r is almost proportional to the internal phase angle φ where the primary flux of a synchronous motor is controlled to be constant. If the parameters of a motor are given exactly, the speed regulation is quite small and the transient characteristics with high response and high starting torque are obtained. Furthermore, it is possible to operate a synchronous motor in the field-weakening range. Here, the principle of the control method and the performance characteristics of a dc brushless motor having no position sensors are discussed. The simulation and the experimental results of the tested machine show that the proposed method is very useful for practical applications.