Showing papers by "Kyushu University published in 1978"

Studies on protein folding, unfolding, and fluctuations by computer simulation. II. A. Three‐dimensional lattice model of lysozyme

Abstract: A three-dimensional lattice model of protein designed to assimilate lysozyme is introduced. An attractive interaction is assumed to work between preassigned specific pairs of units, when they occupy the nearest-nighbor lattice points. The behavior of this lattice lysozyme is studied by a Monte Carlo simulation method. Because of the specific interunit interactions,“native state” of the lattice lysozyme is stable at low temperatures. Conformational fluctuations in the native state are observed to occur at both termini and loop regions of the main chain existing on the surface. The process of unfolding and denatured states of this model are discussed. Complete refolding from a denatured state was not observed. However, by starting from partially folded structures, the native conformation could be attained. From these observation it is concluded that, in the process of folding of proteins as simplified in a lattice model, nulceation is a rate-limiting factor. The artificial character of this model and possible improvement are discussed.

Visual observations of the flow past a sphere at Reynolds numbers between 10 4 and 10 6

Abstract: The wake configuration of a sphere has been determined by means of the surface oil-flow method, the smoke method and the tuft-grid method in a wind tunnel at Reynolds numbers ranging from 104 to 106. It was found that the wake performs a progressive wave motion at Reynolds numbers between 104 and 3·8 × 105, and that it forms a pair of stream wise line vortices at Reynolds numbers between 3·8 × 105 and 106.

Study of metal oxide catalysts by temperature programmed desorption. 4. Oxygen adsorption on various metal oxides

Abstract: Temperature-programmed desorption of oxygen from 16 metal oxides showed that no significant desorption occurred at 10/sup 0/-560/sup 0/C from V/sub 2/O/sub 5/, MoO/sub 3/, Bi/sub 2/O/sub 3/, WO/sub 3/, and Bi/sub 2/O/sub 3/.2MoO/sub 3/ (Group A); that varying amounts of oxygen, always amounting to a few per cent of surface coverage, desorbed with up to four desorption peaks from the transition metal oxides Cr/sub 2/O/sub 3/, MnO/sub 2/, Fe/sub 2/O/sub 3/, Co/sub 3/O/sub 4/, NiO, and CuO (Group B); and that oxygen desorbed from TiO/sub 2/, ZnO, SnO/sub 2/, Al/sub 2/O/sub 3/, and SiO/sub 2/ only after evacuation at 600/sup 0/C and oxygen treatment near room temperature (Group C). The desorbed oxygen was probably associated with surface defects such as vacancies, edges, and corners. The amount of oxygen desorbed from Group B and C oxides decreased with increasing heat of oxide formation. Adsorption on silica and alumina was probably physisorption. Adsorption of oxygen on Group A oxides was probably followed by migration into the bulk and incorporation into the lattice. On Group C oxides, the O/sub 2/(-1) ion was directly identified by ESR spectroscopy.

Electroencephalographic studies myoclonus.

Abstract: Electroencephalographic studies were carried out in 30 patients with various kinds of myoclonus. It was confirmed that the technique of jerk-locked averaging with a backward averaging program was useful for detecting cortical spikes in association with the spontaneously occurring myoclonus, which are not recognized on the convential polygraph, and for evaluating the temporal and topographical relationship between the spike and the myoclonus. By this technique, cortical spikes were shown to precede the myoclonus of a contralateral upper extremity muscle by 7 to 15 ms ith progressive myoclonic epilepsy showed a high amplitude somatosensory evoked potential (SEP) in response to electrical stimulation of the median nerve. The N33 component of this high amplitude SEP was found to be similar to the myoclonus-related cortical spike in their wave form, time relationship and topographical distribution, suggesting an involvement of similar physiological mechanisms in the genesis of both phenomena. Myoclonus in these patients is compatible with "pyramidal" or "cortical loop reflex" type.

Clinical studies of the movement-related cortical potential (MP) and the relationship between the dentatorubrothalamic pathway and readiness potential (RP).

Abstract: In order to investigate the influence of basal ganglia and cerebellar involvement on the preparatory state of the cerebral cortex for voluntary movement, the cortical potential preceding finger movement was studied in 20 patients with Parkinson's disease and 20 patients with cerebellar ataxia. Readiness potential (RP) was abnormal in 90% of the Parkinson group and in 55% of the cerebellar ataxia group. The most frequent abnormality was a depressed amplitude and earlier onset of RP in both groups. The most remarkable finding in the present study was the complete absence of RP with dyssynergia cerebellaris myoclonica (presumed Ramsay Hunt syndrome) whereas normal RP was obtained with cerebellar cortical degeneration. In addition, RP was absent or severely depressed in patients with a unilateral vascular lesion of the midbrain (Benedikt's syndrome) and in patients with Parkinson's disease who underwent unilateral intermedioventral (Vim) thalamotomy. These facts suggest a possible important role of the dentatorubrothalamic or dentatothalamic pathway in the physiogenesis of RP.

Protandrous hermaphroditism in six species of the anemonefish genus Amphiprion in Japan

Abstract: Population structure and gonad histology were investigated in six species of the anemonefish genus Amphiprion occurring in Japanese waters.Species investigated included Amphiprion frenatus,A.clarkii,A.polymnus,A.perideraion,A.sandracinos,and A.ocellaris. All six species occur around their host anemones in small social groups that include a monogamous pair of sexually functional adults and from zero to three sexually non-functional subadults and juveniles.In all species,the single female in a particular social group is larger than her mate,considerably so in some species.Histological examination of gonads indicated that all individuals of all six species are ambosexual as juveniles.At first only testicular tissues mature.Under certain conditions these may later degenerate and the gonads change to ovaries.Field studies supported histological results.A strict dominance hierarchy exists in each social group.The largest fish is always the single female,and the second largest fish is invariably a functional male.Only the two largest fish are sexually functional.Two functional males of A.clarkii under study in the field changed to females after the loss of their previous mates.The six Amphiprion species in Japan present examples of socially controlled protandrous sex inversion. In the course of field studies of anemonefishes at Sesoko Island,Okinawa,in 1975,it was found that Amphiprion frenatus Brevoort usually appeared around the host anemone in social groupings that included an adult pair and one or two juveniles,and that a remarkable size difference consistently appeared among the adults,with females considerably larger than males.A similar but less obvious female/male size ratio had previously been described for Amphiprion clarkii(Bennett)by Moyer and Sawyers(1973).Late in 1976,two individuals of A.clarkii at Miyakejima,Izu Islands,were noted to have changed from males to females.These facts indicated the possibility of protandrous hermaphroditism in these species,and led to investigations of other Amphiprion species in the Ryukyu Islands. Subsequently,Fricke(1976)and Fricke and Fricke(1977)described protandrous sex inversion in Amphiprion bicinctus Riippell from the Gulf of Aqaba,Red Sea,and in A.akallopisos Bleeker from Aldabra in the Indian Ocean.Ross(1978)noted a similar sex change in A.melano pus Bleeker from Guam. The present study describes the social structure of six species of anemonefishes from Japan and reports the results of histological studies of their gonads. Materials and Methods From 1975-1977,field observations of the social behavior and social structures of Amphiprion frenatus,A.clarkii,A.polymnus (Linnaeus),A.perideraion Bleeker,A.sandracinos Allen,and A.ocellaris Cuvier were made using SCUBA or by snorkeling in the waters of Sesoko Island,Okinawa Island,Miyako Island,Ikema Island,and Kuroshima in the Ryukyu Islands,and at Miyake-jima in the lzu Islands.Specimens were collected using hand and screen nets,and were preserved in 10% formalin after weighing and measuring. In specimens larger than 41 mm in standard length,gonads were removed and prepared in 7p paraffin sections.In specimens of 40 mm or less in standard length,cross sections of the entire abdominal region were prepared after decalcification in 5% formic acid.The sexes of the fishes were determined under a microscope after staining with haematoxylin and eosin.Fish specimens are deposited at the Tatsuo Tanaka Memorial Biological Sta.tion (TMBS),Miyake-jima,and gonad preparations are in the Fishery Research Laboratory of Kyushu University.

Deoxyribonucleic Acid Relatedness between Bacillus anthracis, Bacillus cereus and Bacillus thuringiensis

Abstract: proved as distinct taxa (1, 2), as they are different in pathogenicity and in some other properties. However it is also widely accepted that they are quite similar. In fact some pathogens may produce non-pathogenic offsprings that are hardly distinguishable from normal B. cereus. Some B. cereus strains share some flagella antigens with B. thuringiensis (6; Ohba and Aizawa, unpublished data), and the formation of intracellular protein crystals, which has been considered as another characteristic of the latter, is now known in Bacillus subtilis (4) too. In their comprehensive studies Smith et al (9, 10) and Gordon et al (3) emphasized their similarities rather than difference and took a view that they are from academic viewpoint the different varieties of B. cereus. Since DNA homology was introduced as a new taxonomic criterion, Somerville and Jones (11) made some DNA-DNA competition experiments and suggested close interrelatendness of the three, though their data do not appear very clearcut. DNADNA hybridisation studies by Azuma (personal communication) and by Seki et al

Regulation by Dietary Fats of 3-Hydroxy-3-Methylglutaryl-Coenzyme a Reductase in Rat Liver

Abstract: TAKASHI IDE, HIROSHI OKAMATSU ANDMICHIHIRO SUGANOLaboratory of Nutrition Chemistry, Department of FoodScience and Technology, Kyushu University School ofAgriculture, Fukuoka 812 JapanABSTRACT The effects of various dietary fats on the activity of3-hydroxy-3-methylglutaryl-Coenzyme A (HMG-CoA ) reducA­asein rat livermicrosomes, the rate-limiting enzyme in cholesterogenesis, were examined.A series of experiments demonstrated the dependency of the HMG-CoAreducA­aseactivity on the nature of dietary fats. When saturated fats withchain length of 12 to 18 were the dietary sources and were fed at the 10%level for 19 days, feeding fats with shorter chain fatty acids caused a lowerenzyme activity compared to those with longer chain fatty acids. Theactivity was also regulated by the degree of unsaturation of dietary fats;when safflower oil, camellia oil or tristearin were fed at the 10% level for18 days, the higher the unsaturation, the lower the activity. When tri-myristin or tripalmitin were fed at the 10% level for 14 days, addition ofessential fatty acid, at the level of minimum daily requirement (1% wasreplaced by safflower oil), did not affect the enzyme activity. Though therate of incorporation of mevalonate into cholesterol in the 12,500 X gsupernatant fraction of the liver was also found to be influenced by thetypes of dietary fats, the extent of the response appeared much smallerthan that of HMG-CoA reductase. No consistent correlation between theHMG-CoA reductase activity and the content of microsomal cholesterol orcholesteryl ester and the fatty acid composition of microsomal lipids wasobserved. J. Nutr. 108: 601-612, 1978.INDEXING KEY WORDS hepatic cholesterogenesis •HMG-CoAreductase •dietary fats •essential fatty acid •microsomal cholesterol3-Hydroxy-3-methylglutaryl-Coenzyme A etary corn oil stimulated the enzyme ac-(HMG-CoA) reductase [EC 1.1.1.34] is tivity in proportion to the amount addedknown to be the rate-limiting enzyme of to a fat-free diet. In the hamster dietarycholesterogenesis in animal tissues. The ethyl palmitate stimulated, whereas ethylactivity of hepatic HMG-CoA reductase is linoleate, depressed, hepatic HMG-CoA re-controlled by the nutritional and hormonal ductase (6). Further information on thestate of the animals (1-3). One of the nu- effects of differences in the composition oftntional factors controlling the activity of dÂiet fats Qn th e actiyify of thethis enzyme in the liver is the amount and ,. , ., ,, u, . .A“nature of dietary fat. Craig et al. (4) ob- Ilver arf not available although there areserved in rats a decrease in the activity by some data showing that hepatic choles-changing the diets from a closed formula, terogenesis measured using acetate as anon-purified stock diet to a fat-free diet.

Affinity Purification and Properties of Cathepsin-E-Like Acid Proteinase from Rat Spleen

Abstract: A unique acid proteinase different from cathepsin D was purified from rat spleen by a method involving precipitation at pH 3.5, affinity chromatography on pepstatin-Sepharose 4B and concanavalin A-Sepharose 4B, chromatography on Sephadex G-100 and DEAE-Sephacel, and isoelectric focusing. A purification of 4200-fold over the homogenate was achieved and the yield was 11%. The purified enzyme appeared to be homogeneous on electrophoresis in polyacrylamide gels. The isoelectric point of the enzyme was determined to be 4.1-4.4. The enzyme hydrolyzed hemoglobin with a pH optimum of about 3.1. The molecular weight of the enzyme was estimated to be about 90000 by gel filtration on Sephadex G-100. In sodium dodecylsulfate polyacrylamide gel electrophoresis, the purified enzyme showed a single protein band corresponding to a molecular weight of about 45000. The hydrolysis of bovine hemoglobin by the enzyme was much higher than that of serum albumin. Various synthetic and natural inhibitors of the enzyme were tested. The enzyme was inhbited by Zn2+, Fe3+, Pb2+, cyanide, p-chloromercuribenzoate, iodoacetic acid and pepstatin, whereas 2-mercaptoethanol, phenylmethyl-sulfonyl fluoride and leupeptin showed no effect.

A new conditional lethal mutator (dnaQ49) in Escherichia coli K12.

Abstract: A conditional lethal mutator, dnaQ49, was found in Escherichia coli K12. The dnaQ49 mutation caused stimulation of rifampicin-, nalidixic acid- and streptomycin-resistant mutation frequencies 100 to 2000 fold at 30°C and the frequencies were further increased 50 to 100 fold at 35°C or higher temperatures. Cells carrying dnaQ49 were unable to grown in salt-free L-broth at 44.5°C, and DNA synthesis but not protein synthesis of the cells was suppressed under the restrictive conditions. The dnaQ gene was located at about 5 min on the E. coli linkage map and the order of the genes residing in this region was determined to be on A-dnaE-metD-dnaQ-proA.

The passage of spermatozoa through the vitelline membrane in the domestic fowl, Gallus gallus

Abstract: The developing outer layer of the vitelline membrane of the ovum in the posterior part of the infundibulum of the domestic fowl contains many spermatozoa in nearly parallel orientation with its inner layer. When the acrosomal region of a spermatozoon approaches or contacts the inner layer, promptly undergoes the acrosome reaction. The outer acrosomal membrane and overlying plasma membrane fuse together and the apical region of the acrosome opens, so that the acrosomal contents are released. Meanwhile the spermatozoon remains a time in contact with the surface of the inner layer, and the network of the inner layer just under the tip of the sperm head begins to be dissolved. This dissolution extends downward forming a tunnel, approximately 9 μm in diameter. The spermatozoon then passes through the inner layer obliquely via the central region of the tunnel and arrives at the perivitelline space.

Theory of Early Stage Spinodal Decomposition in Fluids near the Critical Point. II

Abstract: In Figs. 3, 4, 5 and 6 the experimental points and the dashed lines of LBM have been taken from Ref. 1). Recently Professor Goldburg and Dr. Schwartz communicated to us that in Ref. 1) an error of factor 2 in time scale occurred in plotting the LBM results corresponding to 2-r=!"LBM· This is also true in our work provided that L=L (or r=1), and the lines of LBM should be shifted to the left accordingly. On the other hand, if L~L" as in our case, we have 2r-r=rLBM and the factor 2r is 1 r=1/2 as in our work. Then this error dissappears. In our work we have regarded the LBM results to be applicable to the model in which L=L" (that is, the renormalization contribution to L comes from fluctuations with k>A=tr:) and long-range hydrodynamic interactions are absent. On the other hand, in drawing the LBM curve in Fig. 5 and the LBM curve with c=1/ v3 ( _,_) in Fig. 10 we have chosen r=L Thus, in order to be consistent with the above-mentioned interpretation of the LBM results, these curves ought to be moved appropriately to the right.

Evolution of overlapping genes.

Abstract: THE nucleotide sequence of the DNA of φX174 phage established by Sanger's group1,2 has revealed that this phage has two overlapping genes in which the same stretch of DNA can code for two proteins which are translated in different reading frames. That two overlapping genes occur in the same DNA genome suggests that this overlapping expression is not unique to φX174 but of more general significance, at least in organisms with small DNA molecules. Once the overlapping expression is established, all mutations in one gene would also alter the other gene within the region of overlap. Some of these mutations, however, may affect one protein but not the other because of codon degeneracy. In general, the evolutionary constraints on a sequence representing both proteins must be very severe. In this report we estimate the extent to which the evolution of a gene is reduced by the acquisition of overlapping expression.

Visual Observations of the Flow past a Circular Cylinder Performing a Rotatory Oscillation

Abstract: The flow around a circular cylinder performing a rotatory oscillation about its axis in a uniform flow has been investigated experimentally by means of flow visualization methods at Reynolds numbers between 30 and 300 and Strouhal numbers between 0 and 55. It has been found that the dead water region is reduced as the frequency of the oscillation is increased, and that the critical Strouhal number at which the dead water region vanishes is approximately proportional to the reciprocal of the angular amplitude of oscillation, but is independent of the Reynolds number. It has also been found that when the Strouhal number is much higher than the critical Strouhal number the flow past the cylinder is strongly accelerated.

The effects of acetylcholine on the membrane and contractile properties of smooth muscle cells of the rabbit superior mesenteric artery

Abstract: 1 Effects of acetylcholine (ACh) on the membrane potential and mechanical properties of rabbit superior mesenteric artery were investigated by the use of microelectrode and isometric tension recording methods. The membrane potential was -62.5 +/- 3.0 mV (s.d.). The maximum slope of the membrane depolarization produced by tenfold increase in [K](0) plotted on a log scale was 48 mV. Excess [K](0) and low [K](0) depolarized the membrane and produced contraction (contracture). The minimum depolarization to produce contraction was 10 mV.2 Low concentrations (10 and 100 ng/ml) of ACh hyperpolarized the membrane. Increased concentrations of ACh (1 and 10 mug/ml) hyperpolarized the membrane further in adult rabbit, while increased concentrations of ACh produced a smaller hyperpolarization in young rabbit. These potential changes produced by ACh in immature and adult rabbits were suppressed by treatment with atropine (0.1 mug/ml).3 ACh (10 ng to 1 mug/ml) consistently generated contraction in Krebs solution. However, ACh relaxed the contraction induced by either K(+) or noradrenaline in the adult rabbit, and it enhanced contraction produced by this treatment in the immature rabbit. In Ca-free EGTA solution, the action of ACh on the mechanical response was markedly suppressed, although high concentrations of ACh still evoked contraction. However, treatment with atropine (1 mug/ml) completely prevented these actions of ACh.4 ACh-induced relaxation during either K(+)-induced or noradrenaline-induced contraction was not caused by the hyperpolarization of the membrane.5 It is concluded that ACh possesses dual actions on smooth muscle cells of the rabbit superior mesenteric artery in Krebs solution, i.e. ACh hyperpolarizes the membrane, while it consistently generates contraction. These ACh actions on the muscle cells were modified by aging.

Thermodynamic studies on adsorption at interfaces. II. One surface-active component system: Tetradecanol at hexane/water interface

Abstract: In order to show that the thermodynamic [ J. Colloid Interface Sci. 64 , 348 (1978)] treatment developed in Part I is useful in studying the adsorption of surface-active substances at interfaces, comparison has been made with a system consisting of water and dilute solution of tetradecanol in hexane. As the system is trivariant, we have chosen the temperature, pressure, and mole fraction of tetradecanol in hexane for the thermodynamic independent variables and measured the interfacial tension as their functions. By means of the thermodynamic equations derived in Part I, the interfacial concentration of tetradecanol and thermodynamic quantities of interface formation have been determined from the experimental results. Further, the partial molar thermodynamic quantity changes at the adsorption have been calculated. It has been observed that the thermodynamic quantities of interface formation decrease, while the interfacial concentration increases with increasing the mole fraction of tetradecanol. The results are explicable in terms of negative values of the partial molar quantity changes.

Melting and crystallization of poly(vinylidene fluride) under high pressure

Abstract: Precise melting and crystallization temperatures of extended-chain and folded-chain crystals of form I and folded-chain crystals of form II poly(vinylidene fluoride) under high pressure have been obtained by microdifferential thermal analysis (DTA). Upon heating at pressures above 4000 kg/cm2, the micro-DTA thermogram of form II crystallized from the melt at atmospheric pressure shows melting of the form II structure and the melting of the folded-chain and extended-chain crystals of form I, formed through recrystallization processes. These features were clarified by supplemental methods. The bandwidth seen in electron micrographs of the extended-chain crystal of form I obtained by crystallization under high pressure was in the range of 1500 to 2000 A. At atmospheric pressure, the extended-chain crystal of form I melted at 207°C, approximately 17°C higher than the folded-chain crystal of form I and 31°C higher than the folded-chain crystal of form II.

Population Structure, Reproductive Behavior and Protogynous Hermaphroditism in the Angelfish.

Abstract: Population structure,reproductive behavior and protogynous sex inversion of the angelfish Centropyge interruptus was studied in the waters of Miyake-jima,Japan.A single male dominates a harem of from one to four females,with the size of the harem being dependent upon the nature of the substrate.Females are controlled by aggressive herding by the single male.Six action patterns associated with maintenance of dominance by the male and with courtship are described.These include(1)rushing,(2)circling,(3) soaring,(4)mutual soaring,(5)nuzzling,and(6)spawning.Spawning usually takes place almost every day at approximately sunset during the period from May to October. Removal of the male resulted in sex change by the ranking female.Histological examination of the gonads confirmed field observations of protogynous sex inversion.The histology of the gonads of females,males and intermediate individuals is described. Studies of reproductive strategies and population structures of pomacanthid fishes are scarce.Lobel(1975),Shen and Liu(1976)and Suzuki et al.(1977)have reported on various aspects of reproduction in the genera Centropyge and Genicanthus.Most of these studies have been based mainly on aquarium observations and do not cover all aspects of reproductive behavior.Population structure remains unknown for any of the Pomacanthidae (Ehrlich,1975). Since the taxonomic revision of the angelfishes by Fraser-Brunner(1933),considerable controversy has appeared in the literature concerning the classification of angelfishes. Yasuda and Tominaga(1970)united Genicanthus with Holacanthus;however,Randall(1975) preferred to follow Fraser-Brunner(1933)in separating them into two genera.Centropyge interruptus(Tanaka)was long erroneously identified as C.fisheri Snyder.Holacanthus interruptus was resurrected by Tominaga and Yasuda(1973);however,Randall and Wass (1974)placed the species in Centropyge, partly on the basis of feeding habits.We have followed Randall and Wass(1974)as a result of observations reported in this paper. Detailed studies of both the reproductive units and courtship behavioral patterns of representatives of the various angelfish genera may eventually provide useful tools for classification of this difficult family. The population structure and reproductive behavior of Centropyge interruptus were studied near the Tatsuo Tanaka Memorial Biological Station(TMBS)at Miyake-jima(34•‹05'N, 139'30'E),one of the Izu Islands,from early July,1976,to the end of the spawning season in October,1977.Histological studies of gonads were made at the Fishery Research Laboratory of Kyushu University.This paper reports the results of these investigations. Methods and materials The social behavior of Centropyge interruptus was investigated daily from July to September, 1976-77.Observations were limited to 2-3 dives per week from September to June in both years.More than 300 hours of observations in nature were made using SCUBA. Social interactions were recorded while lying on the bottom within the territory of the social group under study.Individual fish were not marked,but could be identified by location,individual variations in color patterns,and individual behavior.Water temperatures were read from commercial diving guages.Forty specimens ranging from 86 to

Clear cell sarcoma of tendons and aponeuroses: a comparative study of 13 cases with a provisional subgrouping into the melanotic and synovial types.

Abstract: Electron microscopy of two cases of clear cell sarcoma of tendons and aponeuroses showed different fine structures. On the basis of these differences a proposed division is made of melanotic and synovial types of the tumor. A subsequent comparative histological study carried out on these tumors showed that there were histological criteria to separate the melanotic and synovial types of sarcoma. Using these histological criteria eleven further cases of clear cell sarcoma in the files of the Tumor Registry were subdivided. Review of the Tumor Registry material showed that eight were melanotic type tumors and one was a further synovial type tumor. Using these histological criteria there are two further cases in the Tumor Registry which are not clearly classifiable into either group. The present observations indicate that the majority of the so-called clear cell sarcomas are in reality "melanomas of soft parts" with a minority of this type of tumor being of "synovial type".

Thermodynamic Study on the Adsorption of 1-Octadecanol at Hexane/Water Interface

Abstract: The interfacial tension α between water and hexane solution of 1-octadecanol has been measured as functions of temperature T, pressure p, and mole fraction of 1-octadecanol in hexane x10 by the pendant drop method. The curves of γ vs. T, γ vs. p, and γ vs. x10 show noticeable break points. Calculated thermodynamic quantities such as energy changes, entropy changes, and volume changes associated with the adsorption show the points of discontinuity at a certain temperature, pressure, and composition, corresponding to the above breaking points. It has been clarified that the first order phase transition between the expanded and condensed states takes place at the interface like that of monomolecular films spread on water surfaces. The expanded state is characterized by a relatively high energy, high entropy, and large volume, while the condensed state by low energy, low entropy, and small volume.

Karyotype analysis in rice

Abstract: Mitotic chromosomes of rice, Oryza sativa L. (2n=24), were all identified by a newly developed technique. A new technique of cell suspending and flame-drying made chromosomes possible to be well flattened and spreaded. Tissue treatment with KCl and enzyme caused segmental differentiation in chromosome stainability with Giemsa. All chromosomes were able to be identified in a single prometaphase nucleus by individual characteristics. Twelve pairs of chromosomes were gradually different in length and composed of 5 metacentrics, 5 sub-metacentrics and 2 sub-telocentrics including a satellited pair.