Microstructure of Interfacial Region Between Cold-Sprayed Copper Coating and AlN Substrate Coated with Sputtered Titanium and Copper

Cold spraying has been developed as a high-quality coating technique. In this article, copper is deposited on an AlN substrate coated by the sputtering of titanium and copper at a low pressure of less than 1.0 MPa, making this approach suitable for a wide range of engineering applications. In order to understand the adhesion mechanism at the atomic scale, the interfacial regions are carefully observed in thin foil samples from the cross sections of the specimens with a HREM. We find a unique wavy boundary between the sputtered titanium and the sputtered copper. It is assumed that the shear-instability phenomenon occurs due to the cold-spraying process and influences the adhesive strength. Furthermore, the cold-sprayed copper particles are connected directly without any oxidation layer due to the appearance of new metallic surfaces during the impact process. The TEM data clearly reveal the phenomena and mechanisms related to the impact of powder sprayed on the substrate.     

Intrarenal hemodynamic abnormalities in diabetic nephropathy measured by duplex Doppler sonography

Intrarenal hemodynamics were studied by duplex Doppler sonography in 112 inpatients with type II diabetes mellitus (DM; 65 males, 47 females, 58 +/- 13 years old). The resistive index (RI) and pulsatility index (PI) of the interlobar arteries were calculated. The patients were divided into four groups: group I consisted of patients with urinary albumin excretion (UAE) < 20 micrograms/min (N = 42), group II with 20 < or = UAE < 200 (N = 28), group III with UAE > or = 200 (N = 25), and group IV with serum creatinine > or = 1.5 mg/dl (N = 17). Both RI and PI values in groups II, III, and IV were significantly higher than those in the controls (age- and sex-matched healthy persons, N = 37; P < 0.001), and those in group IV were significantly higher than those in groups I, II, and III (P < 0.0001). Multiple regression analysis revealed that RI values in DM patients were significantly affected by creatinine clearance, age, and duration of diabetes (R2 = 0.554, P < 0.0001). When intima-medial thickness (IMT) of the femoral and carotid arteries were measured by B-mode ultrasonography, RI values were significantly correlated with both the femoral and carotid arterial IMT. These results demonstrate that intrarenal hemodynamic abnormalities are present in type II DM patients with nephropathy, and that intrarenal hemodynamics are affected by decreased glomerular function and also probably by advanced arteriosclerosis.     

The long-term results of percutaneous isolated hepatic perfusion for patients with advanced hepatocellular carcinoma

We studied the long-term outcome of percutaneous isolated hepatic perfusion (PIHP) for patients with hepatocellular carcinoma. This study included 31 patients with Stage IVA and 5 with IVB disease treated by PIHP until December, 1997. The mean age and tumor diameter were 55 and 7.7 cm, respectively. Twenty-two had portal vein invasion, 13 had hepatic vein invasion, and all patients had multiple intrahepatic metastases of more than 5 tumor foci. The PIHP with adriamycin or cisplatin was undertaken in a total of 50 treatments in these 36 patients. CR was observed in 6 and PR in 13 with an overall response rate of 59%, excluding 4 patients who were not evaluable. Five of 6 patients with CR remain free of disease at 7 to 54 months after the first treatment. The overall survival rate was 67% at 1 year and 32% at 5 years. The survival rates of Stage IVA patients (1-year = 71%, 5-year = 36%) were higher than Stage IVB patients (1-year = 20%, 5-year = 0%). The 5-year survival rates of patients with vascular invasion (Vp1-3 = 23%, Vv1-3 = 8%) were lower than those without it (Vp0 = 47%, Vv0 = 51%). These results indicated that PIHP achieved a 5-year survival rate of approximately 40% in patients with multiple advanced hepatocellular carcinoma in the absence of distant organ metastases and marked vascular invasion, and yielded complete long-term remission in some of these patients.     

A 16-Mbit DRAM with a relaxed sense-amplifier-pitch open-bit-linearchitecture

A 16-Mb dynamic RAM has been designed and fabricated using 0.5-μm CMOS technology with double-level metallization. It uses a novel trench-type surrounding high-capacitance cell (SCC) that measures only 3.3-μm² in cell size with a 63-fF storage capacitance. A novel relaxed sense-amplifier-pitch (RSAP) open-bit-line architecture used on the DRAM achieves a high-density memory cell array, while maintaining a large enough layout pitch for the sense amplifier. These concepts allow the small chip that measures 5.4×17.38 (93.85) mm² to be mounted in a 300-mil dual-in-line package with 65-ns RAS access time and 35-ns column address access time     

Decreased GA1 content caused by the overexpression of OSH1 is accompanied by suppression of GA 20-oxidase gene expression

We previously reported that overexpression of the rice homeobox gene OSH1 led to altered morphology and hormone levels in transgenic tobacco (Nicotiana tabacum L.) plants. Among the hormones whose levels were changed, GA1 was dramatically reduced. Here we report the results of our analysis on the regulatory mechanism(s) of OSH1 on GA metabolism. GA53 and GA20, precursors of GA1, were applied separately to transgenic tobacco plants exhibiting severely changed morphology due to overexpression of OSH1. Only treatment with the end product of GA 20-oxidase, GA20, resulted in a striking promotion of stem elongation in transgenic tobacco plants. The internal GA1 and GA20 contents in OSH1-transformed tobacco were dramatically reduced compared with those of wild-type plants, whereas the level of GA19, a mid-product of GA 20-oxidase, was 25% of the wild-type level. We have isolated a cDNA encoding a putative tobacco GA 20-oxidase, which is mainly expressed in vegetative stem tissue. RNA-blot analysis revealed that GA 20-oxidase gene expression was suppressed in stem tissue of OSH1-transformed tobacco plants. Based on these results, we conclude that overexpression of OSH1 causes a reduction of the level of GA1 by suppressing GA 20-oxidase expression.     

The effect of lead on intracellular water content of human red blood cells. Part 1. An experiment in vitro (author's transl)

We observed in vitro experiment that lead increased osmotic resistance of normal human erythrocytes and decreased mean corpuscular volume and intracellular potassium. Though the mechanism of the increased osmotic resistance of erythrocytes caused by lead has not yet been completely clarified, the following hypothesis could be accepted. Lead causes leakage of water from erythrocytes, which means that more water can enter the cell before hemolysis occurs. But there has been no report of direct measurement of the intracellular water content of erythrocytes treated with lead. This paper tried to clarify the relationship between intracellular water and osmotic resistance of lead treated erythrocytes in vitro experiment. The results were: 0.05 mumol/ml of lead increases osmotic resistance, trapped water content and plasma water content of normal human blood and decreases intracellular water content after incubation for 2 hours at 37 degrees C.     

Electron-microscopic imaging of single-walled carbon nanotubes grown on silicon and silicon oxide substrates

Direct imaging of single-walled carbon nanotubes (SWNTs) suspended on pillar-patterned Si or SiO2 substrates is investigated using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The suspended nanotubes are successfully observed by direct TEM imaging and it is seen that they have either individual or bundles of SWNTs. Low energy (< or =2 keV) SEM produces high contrast images of suspended SWNTs. On the contrary, when SWNTs contact a SiO2 substrate, they are imaged using electron-beam induced current. The image brightness depends on the length of SWNTs.     

A circuit technology for high-speed battery-operated 16-Mb CMOSDRAM's

A battery-operated 16-Mb CMOS DRAM with address multiplexing has been developed by using an existing 0.5-μm CMOS technology. It can access data in 36 ns when powered from a 1.8-V battery-source, and 20 ns at 3.3 V. However, this device requires a mere 57 mA of operating current for an 80-ns cycle time and only 5 μA of standby current at 3.3 V. To achieve both high-speed and low-power operation, the following four circuit techniques have been developed: 1) a parallel column access redundancy (PCAR) scheme coupled with a current sensing address comparator (CSAC), 2) an N&PMOS cross-coupled read-bus-amplifier (NPCA), 3) a gate isolated sense amplifier (GISA) with low V_T, and 4) a layout that minimizes the length of the signal path by employing the lead on chip (LOC) assembly technique     

Metal Complexes of π-Conjugated Polymers

π-Conjugated chelating polymers such as poly(2,2′-bipyridine-5,5′-diyl), poly(1,10-phenanthroline-3,8-diyl), and salophen polymers have been prepared by organometallic polycondensations. The obtained polymers form metal complexes with various metal species such as [Ru(bpy)₂]²⁺ and CuCl₂. Metal complexes of π-conjugated ligands are also polymerized by dehalogenative organometallic polycondensations. Some of the metal complexes of π-conjugated polymers exhibit electrical conducting nature and show catalytic activity for redox reactions.