Abstract: An object is to provide a means which is useful for the development of an anti-malaria agent. It was found that a mitochondrial DNA polymerase of falciparum malaria shows a bivalent iron ion requirement. Thus, disclosed is a method for measuring the activity of a DNA polymerase, including the steps of: (1) incubating a solution containing a bivalent iron ion, a mitochondrial DNA polymerase of falciparum malaria, template DNA, and at least one deoxyribonucleoside triphosphate or deoxyribonucleoside triphosphate derivative; (2) detecting the synthesized double-stranded DNA; and (3) calculating the activity of the DNA polymerase from the result of the detection carried out in step (2).

Abstract: Provided is an elastic polyurethane fiber comprising a polyurethane obtained by copolymerizing a polymer diol (A), an organic diisocyanate (B) and a chain extender (C);said polymer diol (A) that constitutes the polyurethane being a polyester diol and/or polyesterpolycarbonate diol having an average molecular weight of 1,000 to 6,000, and satisfying the following condition (I); ##EQU1## wherein the total number of carbon atoms means the number of the carbon atoms contained in the polymer diol and excluding those contained in the ester bonds and carbonate bonds thereof;the diol units that constitute said polymer diol containing branched diols in an amount of at least 10 mol %;said polyurethane constituting said elastic fiber satisfying the following conditions (II) and (III)45%.ltoreq.long chain hard segment content.ltoreq.

Abstract: Provided is an elastic polyurethane fiber having excellent hot water resistance, elastic recovery at low temperatures and elongation, prepared from a polyurethane obtained by copolymerization of a high polymer diol obtained from 3-methyl-1,5-pentanediol and an aliphatic dicarboxylic acid, an organic diisocyanate and a chain extender.

Abstract: Provided is an artificial hair made of a copolyester comprising polyethylene terephthalate copolymerized with an improving compound represented by ##STR1## in an amount of 1 to 8 mol %, which can be headset for giving shapes such as curls or waves at a low temperature causing no migration or sublimation of disperse dyes, the shapes thus given being kept stably.Also provided is a process for producing such artificial hair, which can by employment of specific techniques keep the dry heat shrinkage at 170.degree. C. of the obtained artificial hair below 10%. Then the resulting artificial hair exhibits good operatability of the heatsetting procedure.

Abstract: Disclosed herein is polyester-based aritifical hair composed of individual filaments having a thickness of 30 to 70 denier, with a deviation of plus and minus 20 denier, and a roughened surface formed such that the average intervals of adjacent pits are 0.1 to 1.5 .mu.m and the density of pits is 5 to 100 pits in a planer distance of 10 .mu.m. The artificial hair looks like natural hair and keeps its hair style and color unchanged when used both indoors and outdoors.

Abstract: There is provided an improved polyester fiber said improvement comprising (a) said fiber containing a density increasing amount of particles having a specific gravity higher than the polyester polymer from which the fiber is made and (b) a roughened surface thereby providing improved drape and silhouette to woven and knitted fabrics made therefrom.

Abstract: A surface-modified synthetic fiber is provided by plasma irradiating a synthetic fiber containing fine particles. Recesses and projections are formed on the surface of the fiber. The recesses are formed by being etched with plasma in the portion not shielded by the fine particles; the projections are formed by not being etched in the portion shielded by the fine particles. The resulting fiber has an irregular surface such that the distance between the center points of adjacent projections is between approximately 0.03 and 1 microns and the number of projections is between approximately 1 and 200 per square micron.

Abstract: A polyester fiber having an irregularly uneven random surface, having nonuniform recesses and projections forming said surface satisfying the requirement 0.2 micron<X<0.7 micron where X is the planar distance from the deepest point of a recess to the deepest point of another recess located adjacently thereof in the circumferential direction perpendicular to the fiber axis and being present at the density of 10 to 50 in each planar distance of 10 microns in the circumferential direction perpendicular to the fiber axis. Said recesses and projections constituting the random surface have additional microfine recesses and projections within the size range of 50 to 200 millimicrons. A method for producing a polyester synthetic fiber having the above surface structure is also described. The fiber thus obtained features excellent dyeability, i.e. the development and depth of color, and an excellent surface hand.