摘要:
An optically active block polyester copolymer formed of structural units represented by the following general formulas (I) and (II): ##STR1## wherein represents for an asymmetric carbon atom and m and n each represents a natural number in the range of from 300 to 5000 is obtained by subjecting an optically active butyrolactone and a species of lactone other than the optically active butyrolactone to sequential ringopening copolymerization in the presence of a catalyst. This optically active block polyester copolymer possesses a high molecular weight and a high melting point (not less than 130.degree. C.) and forms a biodegradable and hydrolyzable material of high strength capable of tolerating the impacts of actual use.
摘要:
The biodegradable composition comprises at least poly(beta-hydroxybutyric acid) or a biodegradable copolymer thereof and a stereospecifically regular block copolymer having the structure units of formula (I): ##STR1## where R1 is a hydrocarbon group having 1 to 14 carbon atoms, optionally including double bonds, oxygen atoms or both of them; and m and n are respectively an integer ranging from 300 to 5,000, or having the structure units of formula (II): ##STR2## where R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are either a hydrogen atom or a methyl group; and m and n are respectively an integer ranging from 300 to 5,000.
摘要:
The block copolymer of polyesters and polycarbonates comprises at least one of each of the constituting units of (I) and (II) having the general formulae: ##STR1## where the sign * indicates an asymmetric carbon atom; R.sub.1, R.sup.2, R.sup.3 and R.sup.4 are either a hydrogen atom or a methyl group; m and n are respective a natural numbers ranging from 300 to 5000: The block copolymer is obtained by successive ring-opening and copolymerization of optically active .beta.-butyrolactones and cyclic carbonates in the presence of a catalyst.The block polymer obtained has high molecular weight and high melting temperature, and can thus be used as a high strength material for practical use and which has bio-degradable and hydrolyzable nature.
摘要:
An electrophotographic photoreceptor comprising a charge transporting material containing at least one triphenylamine compound represented by general formula (1) and at least one compound selected from the group consisting of a hydrazone compound, a triphenylamine dimer compound and a distyryl compound: ##STR1## said charge transporting material being able to express high carrier mobility, being high in solubility in a binder polymer, and being able to form a homogeneous charge transporting layer.
摘要:
A microorganism represented by a strain K04-0144 belonging to Streptomyces sp. having ability to produce K04-0144 substance is cultured in the medium, and the isolated K04-0144A substance, K04-0144B substance and K04-0144C substance therefrom have strong antibacterial activities against Gram-positive bacteria including methicillin-resistant Streptococcus aureus (MRSA), consequently these are useful as the therapeutic agents for infectious disease caused by MRSA as well as infectious diseases caused by multidrug including β-lactam antibiotics resistant bacteria. Further, similarly, since the novel K04-0144D substance isolated from the cultured liquid has the action for enhancing the effect of β-lactam antibiotics, which are utilized as the antibacterial agents, in combination with them, it is useful as the therapeutic agent for infectious diseases caused by methicillin-resistant Staphylococcus aureus (MRSA) and multidrug including β-lactam antibiotics resistant bacteria.
摘要:
An image detecting apparatus has an edit function with good operability and compatibility. When a chapter mark key on a remote control is pressed while an image reproducing system including an MPEG video decoder, a video signal post-processing circuit, a combining circuit, and an NTSC encoder is reproducing image data recorded on a recording medium, a CPU obtains information for identifying the image being reproduced and displayed, and then records the information on the recording medium. With reference to the image provided with a chapter mark, a still image generating circuit displays reduced still images, for example, so that a target image can be specified. Reproduction and editing can be performed with reference to the specified image.
摘要:
A microorganism belonging to the genus Streptomyces and being capable of producing substance K01-0509-A1 and/or substance K01-0509-A2 is cultured in a medium. Then, the substance K01-0509-A1 and/or the substance K01-0509-A2 having been thus accumulated in the liquid culture medium are collected from the medium. It is expected that the obtained substances are efficacious as drugs which are selectively effective on pathogenic gram-negative bacteria having the type III secretion system.
摘要:
An contour correcting circuit for correcting the contour without deterioration of image quality of the video signal, comprising a first HPF for extracting the high frequency signal component of the video signal supplied from an input terminal Tin, a second HPF for differentiating the output of the first HPF additionally, and a correlator for synthesizing the output signals of the output and the inverted output of said first HPF, and the output of the second HPF to form a signal having a predetermined signal waveform, wherein the correlator forms a signal waveform of the preshoot portion and overshoot portion with the first order differential output which is relatively static at the inflection point of the video signal, synthesizes a second order differential waveform so as to be a sharp signal waveform at the middle portion, and performs sharpness processing of the video signal by use of the contour correction signal.
摘要:
In examining the progress of patients before and after a cataract operation, the morphology of cornea endothelium cells used in medical treatment, may be determined from a cornea endothelium cell image with less labor. Center points of two-dimensionally continuous cells of a cornea endothelium cell image are entered into a computer, and peripheral points obtained by determining peripheral points which are center points of the cells within a specified distance from one center point are sorted clockwise. If an angle formed by successive two peripheral points and the center point is less than a specified angle, the greater of the two peripheral points in distance from the center point is excluded from the peripheral points. If a distance between the first point and the third point of the obtained successive three peripheral points is shorter than a distance between the center point and the second point, the second point is excluded from the peripheral points, and average distances between the peripheral points and the center point are determined. A perpendicular line that proportionally divides a distance between a center point and its peripheral points by their average distances to the peripheral points is determined for each of the successive peripheral points, and intersection points of the resulting perpendicular lines are determined as vertices of the cells. Thus, morphological data are computed from the obtained vertices.