Electrical properties of HgCdTe epilayers doped with silver using an AgNO3 solution

We employed AgNO₃ solutions for doping Ag in liquid phase epitaxy (LPE) grown Hg_0.78Cd_0.22Te epilayers and found that the minority carrier lifetimes became longer so that the diode properties improved. After annealing LPE grown Hg(1-x)Cd(x)Te layers (x=0.22) in Hg atmosphere, the epilayers were immersed in an AgNO₃ solution at room temperature. The typical carrier concentrations of holes was 3 × 10¹⁶ cm⁻³ at 77K. These values were almost the same as for the nondoped wafers. Also, its acceptor level was 3 to 4 meV. This shows that the Ag was activated. The doped crystals have lifetimes several times longer than those of the nondoped crystals. Numerical fitting showed the lifetime was limited mostly by the Auger 7 process. The Shockley-Read-Hall recombination process was not effective. To examine the Ag-doped wafer, we fabricated photodiodes using standard planar technology. The diodes have an average zero-bias resistance of several MΩ and a shunt resistance of about 1 GΩ for a 10 μm cutoff wavelength at 78K. These values are about four times higher than those of nondoped diodes. The photo current is also two times higher at the same pixel size. This shows that the quantum efficiency is increased. The extension of the lifetime contributes to the high resistance and the high quantum efficiency of the photodiode.     

Room temperature continuous-wave operation of GaInNAs/GaAs VCSELsgrown by chemical beam epitaxy with output power exceeding 1 mW

The authors present a near 1200 nm wavelength vertical-cavity surface-emitting laser (VCSEL) the active region of which is formed by GaInNAs/GaAs quantum wells grown by chemical beam epitaxy. Room temperature continuous-wave operation has been demonstrated with a high slope efficiency of 0.23 W/A, a high output power of over 1.0 mW, and a singlemode output power of 0.34 mW. The fabricated devices with different aperture sizes show low threshold currents of 1.2-2.1 mA and a record low threshold current density of 2.6 kA/cm² in GaInNAs VCSELs     

Can food factors provide Us with the similar beneficial effects of physical exercise?

Metabolic diseases have got global health issues. Physical exercise as well as diet therapy is a potent strategy for fighting against the diseases. However, it is often difficult to continue to keep exercise regularly enough to take sufficient effect. Thus, good substitutes for the therapeutic exercise would be greatly beneficial. Recent studies have suggested that 5′AMP-activated protein kinase (AMPK) play important roles in the metabolic alterations by muscle contraction. The notion that AMPK mediates broad effects of physical exercise has been widely accepted, though it has been challenged by observations in some genetically AMPK-disrupted animals. We have demonstrated metabolome-wide significance of AMPK activation in contracting muscles. Thus, pharmacological activation of AMPK can be a promising way to obtain similar effects of the exercise. The relevance of AMPK will be introduced, and possible strategies for obtaining similar effects to the exercise from food factors will be discussed in the current review.     

Denatured-jacalin derivatives with selective recognition for O-linked glycosides (ST,T, Tn,and STn Type) on IgA1 hinge region

Immunoglobulin A1 (IgA1) concentration in the plasma of patients with IgA nephropathy (IgAN) as the cause of renal failure is higher than that in the plasma of normal controls. IgA1 with abnormal sugars is considered to deposit in the glomerular mesangium, aggravating nephritis in IgAN. Jacalin is a lectin that recognizes sugars on IgA1. However, its selective-recognition for normal-type (ST type, NeuAc-α(2,3)-Gal-β(1,3)-GalNAc) and abnormal-type (T type, Gal-β(1,3)-GalNAc; Tn type, GalNAc; STn type, NeuAc-α(2,6)-GalNAc) sugars α-O-linked to serine/threonine in IgA1 is weak. Therefore, jacalin cannot be used for recognizing specific sugar types on IgA1. We attempted to develop a new recognition method for specific sugar types on IgA1 by utilizing the multirecognition capability of jacalin. Its binding abilities were regulated by heat denaturation with suitable template sugar (galactose or N-acetylgalactosamine). Further, we successfully prepared denatured-jacalin derivatives, which recognized ST-/T-type sugars on IgA1, by sugar-immobilized affinity chromatography. Enzyme-linked immunosorbent assay of denatured-jacalin derivatives, showed the ratios of abnormal sugars on IgA1 in the plasma of IgAN patients and normal controls to be approximately 60% and 20%, respectively. The results proved that profiling of sugar types in IgAN can successfully be performed by solely using jacalin derivatives.     

Compact and power‐saving polysilicon data driver with common‐decoder DA converter (CD‐DAC)

Abstract— A common‐decoder architecture for a data‐driver circuit fabricated by using a polysilicon process has been developed. The architecture achieves a compact circuit and low‐power consumption. In application to an integrated polysilicon data driver for small‐sized displays, this architecture reduces the area of the data driver by removing the vertical bus lines that occupy a large area. It also suppresses the power consumption of the data bus by reducing the number of driven lines in the data bus during word‐to‐word transitions from six to two. By using a conventional 4‐μm design rule, we fabricated an active‐matrix OLED (AMOLED) panel with an integrated six‐bit data‐driver circuit with 384 outputs. The driver circuit had a height of 2.6 mm and a pitch between output lines of 84 μm. The maximum power consumption of the driver was only 5 mW, i.e., 3.8 mW for logic‐data transfer and 1.2 mW for reference‐voltage source. Furthermore, we also fabricated an active‐matrix LCD (AMLCD) panel including driver circuits of the same type as the integrated elements. Six‐bit full‐color images were successfully displayed on both panels.     

Growth of highly strained GaInAs-GaAs quantum wells on patterned substrate and its application for multiple-wavelength vertical-cavity surface-emitting laser array

We carried out the growth of highly strained GaInAs-GaAs quantum wells (QWs) on a patterned substrate for extending emission wavelength on a GaAs substrate. We examined the shift of photoluminescence wavelength of the QWs and showed a large wavelength shift due to the spatial modulation in well thickness and indium composition. We demonstrated a single-mode multiple-wavelength vertical-cavity surface-emitting laser (VCSEL) array on a patterned GaAs substrate covering a new wavelength window of 1.1-1.2 /spl mu/m. By optimizing pattern shape, we achieved multiple-wavelength operation with widely and precisely controlled lasing wavelengths. The maximum lasing span is as large as 77 nm. We carried out a data transmission experiment through 5-km of single-mode fiber with a 2.5 Gb/s/channel. The total throughput reaches 10 Gb/s. The VCSEL-based wavelength-division-multiplexing (WDM) source would be a good candidate for WDM-LAN beyond 10 Gb/s.     

An error evaluation scheme based on rotation of magnetic field in adaptive finite element analysis

The finite-element analysis is widely used in design stage of electromagnetic apparatuses. The analysis accuracy depends on the characteristics of the finite-element mesh, e.g., number of nodes, number of elements and shape of elements. Recently, the adaptive finite-element analysis is one of the most promising numerical analysis techniques. In process of the adaptive finite-element method, the error evaluation is one of the important schemes. In this paper, a new error evaluation scheme, which is suitable for electromagnetic problems, is proposed. The proposed error evaluation method is then applied to two-dimensional and three-dimensional magnetostatic field problems for its verification.     

The measurement of hydrogen activities in molten copper using an oxide protonic conductor

We have developed a hydrogen sensor for in situ measurements of hydrogen activities in molten copper. The sensor consists of a concentration cell utilizing a proton conductor, CaZr_0.9In_0.1O_3-δ, as the solid electrolyte. The electromotive force (emf) of the cell was generated by both hydrogen and oxygen activity gradients across the cell in a high-temperature region simulating the fire refining processes of copper. However, accurate hydrogen activity in molten copper could be evaluated from the emf if oxygen activity in molten copper was determined simultaneously by another concentration cell and if the hydrogen and the oxygen activities at the reference electrode were known. The performance of the sensor was studied under various conditions. The observed good response and reliability of the sensor show that it should be a powerful tool for improvement of the fire refining process of the molten copper. Theoretical treatment of the calculation of the emf of the concentration cells using a mixed ionic conductor, i.e., protonic and oxide ionic conductor, as solid electrolytes is also discussed briefly.     

Changes in microflora of the cloaca and oviduct of hens after intracloacal or intravaginal inoculation with Salmonella enteritidis

Quantitative and qualitative microbiological examination was carried out on cloacal and oviductal contents pre- and postinfection with Salmonella enteritidis (SE) intracloacally or intravaginally. Before inoculation with SE, the means +/- standard deviation (SD) of total bacterial counts, anaerobic bacterial counts, and aerobic bacterial counts in the cloaca were log10 7.7 +/- 0.7, 7.4 +/- 0.2, and 6.9 +/- 0.8 colony-forming units (CFU)/g, respectively. The predominant bacteria were Bacteroidaceae, Lactobacillus, and Escherichia coli. Before inoculation with SE, the means +/- SD of total bacterial counts, anaerobic bacterial counts, and aerobic bacterial counts in the vagina were log10 5.7 +/- 1.4, 5.5 +/- 1.3, and 3.6 +/- 2.7 CFU/g, respectively. Bacteroidaceae and Lactobacillus were predominant. Following inoculation with SE, only the cloacal population of Lactobacillus in hens inoculated intracloacally was significantly increased compared to that before the inoculation. Other indigenous microflora were stable even after the inoculation. In the uterus, very few bacteria, Lactobacillus and Staphylococcus, were isolated. Five of 20 eggs (25%) from hens inoculated with SE intravaginally were positive for SE, whereas no SE was recovered from 22 eggs in hens inoculated with SE intracloacally. SE was recovered from the uterus after intravaginal inoculation with SE and from the vagina after intracloacal inoculation with SE. Contamination may ascend from the cloaca into the lower parts of the oviduct and subsequently contaminated eggs may occur.     

Obstructive jaundice due to multiple hepatic abscesses

A 63-year-old Japanese male with diabetes mellitus developed obstructive jaundice following the onset of multiple hepatic abscesses. Percutaneous transhepatic cholangiography showed intrahepatic bile duct irregularity and dilatations accompanied by a complete obstruction of the right branch of the intrahepatic bile duct. Three kinds of organisms were cultured from the blood and the drained bile. The cholangiographic changes returned to the normal after the liver abscesses subsided following biliary drainage and the administration of intravenous antibiotics.