Polysaccharides as excipients for colon-specific coatings. Permeability and swelling properties of casted films

Oligosaccharides such as inulin (In) and polysaccharides such as galactomannans, combined with polymethacrylates on isolated films for film coatings, were obtained from aqueous-based solvents and investigated as potential vehicles for colonic drug delivery. These compositions, which are susceptible to fermentation by colonic microflora, constitute promising excipients for the development of new colon-specific therapeutic systems. The characteristics of several compositions have been demonstrated in permeability and swelling studies on isolated films composed of a polymethacrylate associated with In or galactomannans of mesquite seed gum (MSG). Results reported prove a dependency of the properties of mixed films on the polymethacrylate-polysaccharide concentration ratio and on the composition of the dissolution media. An increase in permeability through the mixed films was observed in a simulated colonic environment for the following compositions: Eudragit®RS30D-MSG 70 : 30 w/w; Eudragit® RS30D-In 90 : 10 w/w; Eudragit®RS30D-In 76 : 24 w/w.     

Breaking Ability and Interrupting Phenomena of a Circuit Breaker Equipped with a Parallel Resistor or Capacitor

This paper discusses the breaking ability of an air blast circuit breaker (ABB) or SF6 gas circuit breaker (GCB), and the interrupting phenomena around current zero in the case where a resistor or capacitor is connected in parallel with its interrupter to improve the breaking ability. It has been clarified that the use of a parallel resistor for ABB, and that of a parallel capacitor for GCB are the most effective methods to improve the breaking abilities; the parallel resistor not only serves to reduce the rate of rise of the transient recovery voltage (rrrV), but also shifts the current from the interrupter to itself around the current zero, thus reducing the stress for interruption. The improvement of the breaking ability is achieved by reducing the initial average rrrV between zero and 1 microseconds (inherent value), when the parallel capacitor is used with the GCB.     

Fatigue behavior of carburized steel with internal oxides and nonmartensitic microstructure near the surface

The characteristic fatigue behavior of carburized and quenched steel with internal oxides and non-martensitic microstructure near the surface was presented through rotating bending fatigue test. The S-N diagram revealed two knees and the specimens continued to fail over 10⁷ stress cycles. The fatigue limit could not be obtained even at 10⁸ stress cycles. The test results were compared to those for the specimens without surface structure anomalies to show the effect of structure anomalies on the fatigue behavior of carburized steel.     

Lung phosphatidylcholine and fasting in male and female rats

Lung from male and female rats fasted for 4 days were used. Phospholipid, phosphatidylcholine and its molecular species were analyzed in lungs from these rats and effects of fasting upon the biosynthesis of phosphatidylcholine in lungs from both sexes were determined using radioactive choline. The molecular species of phosphatidylcholine in both male and female rats did not differ with fasting except the monoenoic species. Incorporation of choline into phosphatidylcholine in both male and female rats significantly increased after fasting, but distribution of radioactivity in phosphatidylcholine yielded similar values in each group. These results suggest that the decrease of saturated phosphatidylcholine content after fasting may be not due to specific change in saturated phosphatidylcholine.     

Phase relationship on Mo-S system at high temperatures

Changing the partial pressure of sulfur Ps₂ at temperatures of 750° and 950°C, phase equilibria on the Mo-S system by solid-gas reaction were investigated. Hexagonal 2H-MoS₂ and monoclinic Mo₂S₃ phases were identified from the x-ray powder diffraction pattern. The 2H-MoS₂ had a slight homogeneity range, i.e. MoS_1.978 to MoS_2.0 at 950°C, MoS_1.983 to MoS_2.0 at 750°C. No remarkable variation of lattice parameters for the MoS₂ was observed. The composition of the Mo₂S₃ phase was not stoichiometric MoS_1.5 but MoS_1.457 at 950°C. At 750°C the composition of the Mo₂S₃ phase could not be determined since it was quite difficult to establish the equilibrium state between the gas and the condensed phases. This finding agreed well with the result of Morimoto and Kullerud.     

Illumination normalization with time-dependent intrinsic images for video surveillance

Variation in illumination conditions caused by weather, time of day, etc., makes the task difficult when building video surveillance systems of real world scenes. Especially, cast shadows produce troublesome effects, typically for object tracking from a fixed viewpoint, since it yields appearance variations of objects depending on whether they are inside or outside the shadow. In this paper, we handle such appearance variations by removing shadows in the image sequence. This can be considered as a preprocessing stage which leads to robust video surveillance. To achieve this, we propose a framework based on the idea of intrinsic images. Unlike previous methods of deriving intrinsic images, we derive time-varying reflectance images and corresponding illumination images from a sequence of images instead of assuming a single reflectance image. Using obtained illumination images, we normalize the input image sequence in terms of incident lighting distribution to eliminate shadowing effects. We also propose an illumination normalization scheme which can potentially run in real time, utilizing the illumination eigenspace, which captures the illumination variation due to weather, time of day, etc., and a shadow interpolation method based on shadow hulls. This paper describes the theory of the framework with simulation results and shows its effectiveness with object tracking results on real scene data sets.     

Speech recognition using pulse-coupled neural networks with a radial basis function

We have developed a novel pulse-coupled neural network (PCNN) for speech recognition. One of the advantages of the PCNN is in its biologically based neural dynamic structure using feedback connections. To recall the memorized pattern, a radial basis function (RBF) is incorporated into the proposed PCNN. Simulation results show that the PCNN with a RBF can be useful for phoneme recognition. This work was presented in part at the 7th International Symposium on Artificial Life and Robotics, Oita, Japan, January 16–18, 2002     

The effects of ce additions on the high temperature corrosion behavior of Fe-30Cr-5Al alloy in 80 Pet Na2SO4-20 Pct NaCI molten salt

High temperature corrosion tests in 80 pct Na₂SO₄-20 pct NaCI were made on five Fe-30 wt pct Cr-5 wt pct Al alloys containing various amounts of cerium up to 0.68 pct. After the corrosion tests, samples were examined metallographically and by X-ray diffraction and X-ray microanalysis. It was found that the surface scale formed on each sample decreased in thickness as the Ce content increased. Electron probe microanalyses suggest that this retarding behavior is related to the early formation of a Ce-induced protective scale of α-Al₂O₃. The role of Ce in promoting the formation of the α-Al₂O₃ scale is discussed.     

Delivery of medical multimedia contents through the TCP/IP network using RealSystem

We developed a low cost, user-friendly multimedia delivery system, to provide medical lectures saved as multimedia contents to persons engaged in medicine. This system was created using the RealSystem package with the TCP/IP network. Users can review lectures and medical meeting presentations with video and audio through the Internet, whenever convenient. Each medical source of video and slide has been clearly displayed on a screen. Members of medical associations or medical students can easily review the most interesting parts of these files. This system is being used efficiently in distance learning and aids the diffusion of the latest information and technology to busy physicians and medical students.     

Scanning electron microscopy of food-poisoning bacterium Bacillus cereus using a variable-pressure SEM

A variable-pressure scanning electron microscopy (VP-SEM) with a cooling stage permits long hours of observation of water-containing specimens in their natural or close to natural state, without the conventional specimen preparations of fixation, dehydration, drying and metal coating. It reduces water vaporization and beam damage by keeping the specimens at a low temperature. We observed Bacillus cereus colonies on nutrient agar, which would shrink significantly if any conventional specimen preparation technique were used. We also studied the growing process of the bacteria on raw and steamed rice using the VP-SEM without conventional preparation techniques. Original specimens were directly mounted onto specimen holders and their backscattered electron images observed under the following conditions: specimen stage temperature, -10 degrees C; specimen chamber vacuum level, 30-70 Pa; and accelerating voltage, 15-20 kV. We recognized that the VP-SEM minimized deformation of the colonies due to shrinkage of the nutrient agar, and successfully imaged the morphology of the colonies and bacteria without a decline in bacteria number, which is apt to occur during fixation and dehydration. Also, the growth process of the bacteria on raw or steamed rice could be observed promptly, since there is no specimen preparation step.