An analytical study of the effect of a support geometry on frequency shift and support loss of piezoelectric ring-shaped resonators for healthcare and environmental applications

Ring-shaped resonators with one support have been designed in this work. The ring-shaped resonator reacts with a mass perturbation to provide eigenstate or frequency shifts which could transfer to electrical signals by piezoelectric effect. The aforementioned ring-shaped resonator is mainly comprised with a multilayer of Pt/Ti/PZT/Pt/Ti/SiO₂ deposited on the silicon-on-insulator wafer and expected to be a contour mode. In order to estimate the sensitivity of the ring-shaped resonator against the mass perturbation, the theoretical analysis was conducted by ANSYS from two aspects including: (a) the effect of support geometry on frequency shift and support loss (from view point of vibration mode shape); and (b) the mass application methodology. It is found that low-amplitude vibration area is smaller at narrow support, and frequency shift of trapezoid support is higher than that of rectangle support.     

Passive piezoelectric single-side MEMS DC current sensor with five parallel PZT plates applicable to two-wire DC electric appliances without using cord separator

A passive (power-less), non-contact macro-scale piezoelectric bimorph DC current sensor to satisfy the increasing needs of DC power supply for monitoring the electricity consumption by either one-wire or two-wire appliance cord was proposed at our laboratory previously. In present study however, a MEMS-scale piezoelectric single-side DC current sensor, comprised of five parallel PZT plates, was further proposed and micro-fabricated for preliminarily examination. A micro magnet was fixed by manipulator onto the PZT cantilever tip to the theoretically pinpointed position of the center plate. Different from the results of the macro-scale piezoelectric bimorph DC current sensor, impulsive piezoelectric output voltages accompanying with a gradual decrease in decay were detected when the applied DC electric current was varied from 0.5 to 2.5 A. A linear relationship between the detected peak value of the impulse output voltage and the applied DC electric current was also obtained but with a higher slope compared to the result of the macro-scale piezoelectric bimorph DC current sensor.     

VHL gene and TSC 2 gene

Hereditary cancer is rare, but it has served as a useful model in the understanding of carcinogenesis. A number of cancer genes have been identified by the study of hereditary human cancers and implicated in sporadic forms of the some tumors. In this article, I reviewed von Hippel-Lindau disease (VHL) gene and tuberous sclerosis 2 (TSC 2) gene.     

Control of chip flow with guide grooves for continuous chip disposal and chip-pulling turning

This paper presents a new chip control method with guide grooves formed on the rake face to realize continuous chip disposal and chip-pulling turning. Chips are conventionally broken using chip breakers during turning operations for disposal. However, chips of highly ductile materials or thin chips generated in finishing can not be broken easily. In order to prevent the chips from jamming up, the authors propose to continuously guide the chips away from the cutting point. Special tool tips were developed and tested for guiding the chip. Chip controllability and mechanics of the chip-guided cutting are discussed in the present research.     

An anaerobic bacterium isolated from Japanese spiny lobster Panulirus japonicus

Eight strains of bacteria which could not grow under aerobic conditions, were isolated from Japanese spiny lobster. All the strains were Gram-positive, non-sporeforming cocci, and grew well under anaerobic conditions. The strains required a decreased oxygen tension rather than an increased CO₂ tension. Catalase, oxidase, nitrate reductase and urease were not produced. The strains fermented glucose, cellobiose, trehalose and levulose. Indole and H₂S were not produced. Macromolecule substances including starch, esculin, casein, gelatin and chitin were not hydrolyzed. Lactic acid was the sole product from peptone-yeast extract-Fildes solution-glucose broth. Fermentable carbohydrates were not required. The strains could grow at 20 to 37°C, and required NaCl for growth. From the above results, the strains were identified as anaerobic (aerotolerant) Streptococcus sp.     

Evidence for Altered Phosphoinositide Signaling-Associated Molecules in the Postmortem Prefrontal Cortex of Patients with Schizophrenia

Phosphoinositides (PIs) play important roles in the structure and function of the brain. Associations between PIs and the pathophysiology of schizophrenia have been studied. However, the significance of the PI metabolic pathway in the pathology of schizophrenia is unknown. We examined the expression of PI signaling-associated proteins in the postmortem brain of schizophrenia patients. Protein expression levels of phosphatidylinositol 4-phosphate 5-kinase type-1 gamma (PIP5K1C), phosphatidylinositol 4-kinase alpha (PIK4CA, also known as PIK4A), phosphatase and tensin homolog deleted from chromosome 10 (PTEN), protein kinase B (Akt), and glycogen synthase kinase 3β (GSK3β) were measured using enzyme-linked immunosorbent assays and multiplex fluorescent bead-based immunoassays of the prefrontal cortex (PFC) of postmortem samples from 23 schizophrenia patients and 47 normal controls. We also examined the association between PIK4CA expression and its genetic variants in the same brain samples. PIK4CA expression was lower, whereas Akt expression was higher, in the PFC of schizophrenia patients than in that of controls; PIP5K1C, PTEN, and GSK3β expression was not different. No single-nucleotide polymorphism significantly affected protein expression. We identified molecules involved in the pathology of schizophrenia via this lipid metabolic pathway. These results suggest that PIK4CA is involved in the mechanism underlying the pathogenesis of schizophrenia and is a potential novel therapeutic target.     

Effect of different features to drill-wear prediction with back propagation neural network

In this paper, a back propagation neural network (BPNN) has been applied to predict the corner wear of a high speed steel (HSS) drill bit for drilling on different workpiece materials. Specially defined static and dynamic features extracted by a wavelet packet transform (WPT) from the resultant force converted from thrust and torque together with the cutting conditions (workpiece material, spindle speed, drill diameter, feed rate) are used as inputs to train the network to obtain a better output, drill corner wear. Drilling experiments have been carried out over a wide range and, features newly defined and conventional ones, features extracted from different frequency bands are compared.     

Hydrogen storage properties of lithium silicon alloy synthesized by mechanical alloying

A lithium silicon alloy was synthesized by mechanical alloying method. Hydrogen storage properties of this Li-Si-H system were studied. During hydrogenation of the lithium silicon alloy, lithium atom was extracted from the alloy and lithium hydride was generated. Equilibrium hydrogen pressures for desorption and absorption reactions were measured in a temperature range from 400 to 500 °C to investigate the thermodynamic characteristics of the system, which can reversibly store 5.4 mass% hydrogen with smaller reaction enthalpy than simple metal Li. Li absorbing alloys, which have been widely studied as a negative electrode material for Li ion rechargeable batteries, can be used as hydrogen storage materials with high hydrogen capacity.     

Intragenic Tsc2 somatic mutations as Knudson''s second hit in spontaneous and chemically induced renal carcinomas in the Eker rat model

Membrane conductances during hypoosmotic swelling were characterized in rat astrocytes in primary tissue culture. Using whole cell patch clamp techniques, mean +/- SEM cell conductance in isoosmotic phosphate-buffered saline (PBS) was 55.6 +/- 5.8 pS/pF. Cell conductance (mean +/- SEM) increased from this initial value to 187 +/- 46%, 561 +/- 188%, and 1216 +/- 376% within 9 min of exposure to 220 mOsm, 190 mOsm, and 145 mOsm PBS, respectively. With each of these hypoosmotic exposures, no change occurred in membrane capacitance. When CsCl replaced KCl in the microelectrode solution, a similar conductance increase was obtained at each osmolality. However, when gluconate salts were used in place of chloride salts in the electrode solution, no significant conductance increase was observed with 190 mOsm PBS. With a KCl microelectrode solution, all conductance increase which occurred in 190 mOsm PBS was inhibited by 200 microM niflumic acid, but not by 5 mM BaCl(2). Both niflumic acid and BaCl(2) inhibited 60-80% of the conductance increase of cells in 145 mOsm PBS. Using a microelectrode solution containing taurine as the major anion, membrane conductance increased 5-fold when cells were placed in 250 mOsm medium. This conductance increase was completely inhibited by 200 microM niflumic acid. Thus, independent chloride and potassium conductances are activated by hypoosmotic swelling of cultured astrocytes while plasma membrane area is unaltered. The chloride conductance pathway is activated at a significantly lower degree of hypoosmotic exposure than that which activates the potassium pathway and may be permeable to anionic taurine. These conductance pathways may mediate diffusive loss of potassium, chloride, and taurine from these cells during volume regulation following hypoosmotic swelling.     

STORAGE OF PITCHING YEAST FOR PRODUCTION OF WHISKY

The viability of pitching yeast stored at 5°C and at 20°C was compared. The viability of the yeast stored at 5°C was about 80% after 54 d storage and its CO₂ producing activity also remained high. The ethanol production rate of yeast stored for a long period at 5°C was unaffected in a subsequent fermentation test, even though the viability was only about 50%. The ethanol production rate of yeast stored at 20°C decreased in proportion to a rapid decrease in viability during storage. The concentration of intracellular sulphur compounds, important for the production of aromatic components of whisky, of yeast stored at 5°C was higher than that of yeast stored at 20°C. Therefore, the storage of yeast at 5°C seems appropriate for production both of ethanol and aroma.