Image classification using spectral and spatial information basedon MRF models

A new criterion for classifying multispectral remote sensing images or textured images by using spectral and spatial information is proposed. The images are modeled with a hierarchical Markov Random Field (MRF) model that consists of the observed intensity process and the hidden class label process. The class labels are estimated according to the maximum a posteriori (MAP) criterion, but some reasonable approximations are used to reduce the computational load. A stepwise classification algorithm is derived and is confirmed by simulation and experimental results.     

Changes in the heparin affinity of extracellular-superoxide dismutase in patients with coronary artery atherosclerosis

Extracellular-superoxide dismutase [EC 1.15.1.1] (EC-SOD) is a secretory glycoprotein with high affinity for heparin. This enzyme locates in blood vessel walls at a high enough level to suppress oxidative stress under normal conditions. EC-SOD is the major SOD isozyme in plasma, anchored to heparan sulfate proteoglycans in the glycocalyx of endothelial cell surfaces. Plasma EC-SOD is heterogeneous in heparin affinity and can be divided into five fractions, I to V, by heparin-HPLC. It has been suggested that EC-SOD form V is the primary form synthesized in the body and that EC-SOD forms with reduced heparin affinity are the result of proteolytic truncation of the C-terminal end of EC-SOD form V which is responsible for the binding with heparin. Recently, we reported that only plasma EC-SOD form V, with the highest heparin affinity, was increased by intravenous injection of heparin. The heparin affinity of plasma EC-SOD in patients with coronary atherosclerosis (CA+ patients) was compared in this study. The increase of plasma EC-SOD form V after heparin injection in CA+ patients was significantly less than that in subjects without evidence of stenosis in their major coronary arteries (CA- subjects). On the other hand, in CA+ patients, EC-SOD forms I to III, with low heparin affinity, were significantly increased compared to those in CA- subjects. EC-SOD in plasma apparently forms an equilibrium between the plasma phase and endothelial cell surface, and EC-SOD on the endothelial cell surface contributes to protecting the vessel wall against oxidative stress. These findings suggest that the quantitative and qualitative changes of EC-SOD, i.e., the decrease of bound EC-SOD on the endothelial cell surface, might suppress the defense systems against oxidative stress, which causes in part the development of coronary artery atherosclerosis.     

Clinical survey of congenital cytomegalovirus infection in Japan

Contrast media-induced nephropathy is one of the leading causes of hospital-acquired renal failure, occurring most frequently in patients with pre-existing renal insufficiency. We prospectively studied 55 patients with chronic renal insufficiency (serum creatinine concentration 1.4 to 3.5 mg/dl) who underwent abdominal aortography and arteriography of the lower extremities. The patients were randomized into two groups. Group 1, 28 patients, received dopamine 2.5 mcg/kg beginning 1 hour before arteriography and continuing for 12 hours. Group 2 received an equal volume of saline for the same period of time. Serum creatinine and 12-hour creatinine clearance were measured before arteriography and for 4 consecutive days afterward. Acute contrast-induced decrease in renal function was defined as increase in the baseline serum creatinine concentration > or = 0.5 mg/dl. On day 1 postarteriography the serum creatinine increased from baseline .193 mg/dl for controls while the dopamine group decreased slightly from baseline .018 mg/dl (p = 0.002). Excepting day 1 postarteriography, there was no statistical difference between groups, and serum levels for both groups increased linearly from baseline across time (dopamine p = 0.028, control p = 0.025). In patients with pre-arteriography baseline serum levels greater than or equal to 2.0 mg/dl, however, the increase in serum creatinine from baseline levels was consistently and significantly greater in the control group through the fourth day (0.012 < or = p < or = 0.049). Creatinine clearance did not change significantly from baseline after arteriography in the dopamine group (baseline versus days 1 through 4, 0.238 < or = p < or = 0.968); however, the control group showed a significant linear decrease in creatinine clearance from baseline through the fourth day after arteriography (p = 0.016). Dopamine infusion prevented a rise in serum creatinine 24 hours after angiography in patients with pre-existing renal insufficiency, and protected against contrast-induced decrease in renal function in patients whose baseline serum creatinine was > or = 2.0 mg/dl.     

Tubulin Photoaffinity Labeling with Biotin‐Tagged Derivatives of Potent Diketopiperazine Antimicrotubule Agents

NPI‐2358 ( 1 ) is a potent antimicrotubule agent that was developed from a natural diketopiperazine, phenylahistin, which is currently in Phase I clinical trials as an anticancer drug. To understand the precise recognition mechanism of tubulin by this agent, we focused on its potent derivative, KPU‐244 ( 2 ), which has been modified with a photoreactive benzophenone structure, and biotin‐tagged KPU‐244 derivatives ( 3 and 4 ), which were designed and synthesized for tubulin photoaffinity labeling. Introduction of the biotin structure at the p′‐position of the benzophenone ring in 2 exhibited reduced, but significant biological activities with tubulin binding, tubulin depolymerization and cytotoxicity in comparison to the parent KPU‐244. Therefore, tubulin photoaffinity labeling studies of biotin‐derivatives 3 and 4 were performed by using Western blotting analysis after photoirradiation with 365 nm UV light. The results indicated that tubulin was covalently labeled by these biotin‐tagged photoprobes. The labeling of compound 4 was competitively inhibited by the addition of diketopiperazine 1 or colchicine, and weakly inhibited by the addition of vinblastine. The results suggest that photoaffinity probe 4 specifically recognizes tubulin at the same binding site as anticancer drug candidate 1 , and this leads to the disruption of microtubules. Probe 4 serves well as a useful chemical probe for potent antimicrotubule diketopiperazines, much like phenylahistin, and it also competes for the colchicine‐binding site.     

Error grid analysis of noninvasive glucose monitoring via gingival crevicular fluid.

In order to realize a noninvasive blood glucose monitor, we monitored the gingival crevicular fluid (GCF). In this paper, the clinical evaluations were performed on not only normal subjects but also diabetic subjects using a GCF-glucose monitor to determine blood glucose levels. Meal load tests were carried out and the time-course changes in blood glucose level and GCF glucose level were measured continuously. A positive correlation of more than 0.9 was found between blood glucose level and GCF glucose level, necessitating the calibration of individual correlations for every subject. Finally, the performance of the GCF-glucose monitor was evaluated using Error Grid Analysis. As the results, significant information for the glucose level decision was obtained not only for normal subjects, but also for diabetic subjects.     

Driving simulator experiment on the moving stability of an automobile under strong crosswind

In expanding expressway networks in Japan, various types of structures have been constructed, e.g., long span bridges and bridges with high piers. The expressway structures are well designed for the external dynamic forces, e.g., earthquakes and strong winds. However, for further safety promotion of the expressway networks, it is important to evaluate the drivers’ responses under strong dynamic disturbances. The present authors have investigated the moving stability of a vehicle under seismic motion based on both numerical simulation and virtual experiments using a driving simulator. Strong crosswind is considered as another factor that makes it difficult for drivers to control their vehicles. This study investigates the moving stability of a vehicle under strong crosswind based on numerical analyses and driving simulator experiments. To predict the future position of a moving vehicle including the reaction of a driver, the second-order predictable correction model is used in the numerical analyses. The results obtained from the numerical and experimental studies are compared and the validity of the driver model is discussed. It is expected that this research is helpful for the decision-making of expressway closure under strong wind and the design of wind barriers.     

Requirements for high-frequency LD FM response in an optical CPFSKheterodyne delay demodulation system

The required high-frequency laser diode (LD) FM responses for a continuous phase frequency shift keying (CPFSK) heterodyne delay modulation system were investigated. The degradations due to insufficient high-frequency FM response are evaluated, considering the FSK waveform distortion, which gives undesired phase error at the demodulation circuit. From the phase error, bit error rate (BER) degradation is calculated. The calculated results indicate that the delay-time adjustment for the demodulation circuit is effective in minimizing the power penalty. The theoretical evaluation, including the demodulation circuit optimization, explains the experimental results fairly well. Using the same evaluation procedure, required high-frequency LD FM responses are derived. The results, together with the required low-frequency FM responses, give guidelines for transmitter LD selection for coherent CPFSK systems     

Preparation of a transparent alumina film doped with CdS and its nonlinear optical properties

We have examined the preparation of transparent alumina film and CdS-doped alumina film prepared by the sol-gel process using aqueous sol starting from AlCl₃. The resulting alumina films obtained by sol-gel transformation are transparent in the visible and near infrared up to 1000 °C. Homogeneous solution of alumina sol and Cd(CH₃COO)₂ was converted into gel film by dehydration. Then, on exposure to H₂S stream at 250–600 °C, a CdS-doped film was obtained. It shows relatively sharp blue-shifted visible absorption that is attributed to size quantization effect. Large nonlinear absorption and refractive index have been obtained, because high concentration of CdS particles can be achieved by using this method.