Showing papers by "Academia Sinica published in 1975"

Establishment of an efficient medium for anther culture of rice through comparative experiments on the nitrogen sources

Abstract: The experiments have revealed that (NH4)2SO4 combined with KNO3 at low concentration is of advantage to the formation, growth and differentiation of pollen callus in rice, whereas the high concentration of (NH4)2SO4, whether used separately or in combination with KNO3, obviously inhibits the pollen callus formation. The optimum NH4+ concen- tration is about 7.0 mM (equal to 3.5 mM (NH4)2SO4). A basic medium containing 3.5 mM (NH4)2SO4 and 28 mM KNO3 as nitrogen sources has been established. On such medium the frequency of the pollen callus formation is higher than that on Millers me- dium, and the differentiation of shoot from pollen callus is satisfactory.

Theory and design of microperforated panel sound-absorbing constructions

Abstract: Theory and design of perforated panel sound-absorbing constructions are well developed,but the difficulties in adjusting the acoustic resistance part of such constructions curtailtheir usefulness. In this paper, a revolutionary idea is proposed that the perforations areto be reduced to submillimetre level so that they themselves will provide sufficient acousticresistance while the low acoustic mass is retained, and so the difficulty of acoustic resis-tances is resolved. Practice shows that this idea is correct. Such panels are now namedmicroperforated panels. Their features are predictable absorption characteristics, simplestructures and in addition, wide frequency bands of absorption. The elimination of porousmaterials makes the microperforated panel constructions windproof and waterproof, andalso heatproof and even flameproof for short time if they are fabricated with sheet metalor other fireproof materials. Theyefore, the problem of wide band, high coefficient soundabsorber for severe circumstances is solved for good. Acoustical properties and unifiedformulae for perforations of all sizes are derived; the theory and characteristics of themicroperforated panel constructions as well as design charts are given to facilitate the prae-tical design work. Ordinary perforated panel constructions are given as a special case.

Phytotoxic substances in twelve subtropical grasses

Abstract: Aqueous extracts of 12 subtropical grasses inhibited seed germination and radicle growth ofLactuca sativa var. Great Lakes at osmotic concentrations as low as 10 milliosmol.Acroceras macrum,Chloris gayana, Digitaria decumbens, andPanicum maximum exhibited the highest inhibition, whileCortaderia selloana revealed the least. Toxic spots were found on chromatograms of the ether fraction of aqueous extracts.Cynodon dactylon, Setaria sphacelata, andTripsacum laxum showed more than six toxic spots, whileAndropogon nodosum,Bracharia mutica, andChloris gayana gave less than three toxic spots. The phytotoxins ferulic, syringic,p-coumaric, vanillic,p-hydroxybenzoic, ando-hydroxyphenylacetic acids were identified. These compounds are differentially distributed in the 12 grasses studied. Additionally, most of these compounds were also found in the associated soils; the control (nonherb-growth) soil provided the toxic compounds in significantly less amount than did the grass soils.

Two polypeptide chain constituents of the major protein of the cornified layer of newborn rat epidermis.

Abstract: The insoluble component of stratum corneum of rat epidermis yields two major bands after extraction with 8 M urea-mercaptoethanol-dithiothreitol. The ratio of these two bands is about 1:1 in terms of protein stain intensity and S-[14C]carboxymethyl label. Both polypeptides were purified to homogeneity by DE-52-cellulose, sodium dodecyl sulfate hydroxylapatite C column chromatography, and preparative DodSO4-polyacrylamide gel electrophoresis. The heavier polypeptide contains 30% alpha helix and the lighter contains 27% alpha helix as determined by circular dichroism studies. Both are sensitive to Pronase and resistant to trypsin, collagenase, and elastase. The lighter chain is stable to pepsin but the heavier can be partially degraded to a smaller polypeptide with a molecular weight similar to that of light chain. Amino acid analysis shows that the light chain contains 12 more tyrosine residues than does the heavy chain, suggesting that the light chain is not generated from the heavy chain. However, the two chains may have a common peptide region. Antiserum prepared against the heavier polypeptide can be completely absorbed by purified lighter polypeptide and vice versa indicating that both chains have some common antigenic determinants. Antibody against either chain can cross-react with the stratum corneum and keratohyalin granules in the epidermis of newborn rat as indicated by fluorescent microscopic observation. Similarly, this antibody also cross-reacts with the cell surface or the contents of spinous and granular cells, and very weakly with basal cells, indicating that the two proteins may be present in the lower strata as well as the stratum corneum.

The Induction of Populus Pollen-Plants

Abstract: Haploid plantlets were successfully induced from Populus nigra anthers cultured in vitro on synthetic medieum.

On the distribution of almost primes in an interval

Abstract: In this paper we shall prove that for a large positive number x there exist at least two integers n in the interval x-x~(1/2)n≤x having at most two prime factors.

Identification of a Sex Pheromone of the Female Brown Dog Tick, Rhipicephalus sanguineus

Abstract: A sex pheromone and an antioxidant compound isolated from the female brown dog tick, Rhipicephalus sanguineus (Latreille), were identified as 2,6-dichlorophenol and 2,6- di-tert-butyl-4-methyl phenol by GC and GC-MS. Amount of 2,6-dichlorophenol present was ca. 2–3 ng per female.

Discovery of a gigantopithecus tooth from bama district in kwangsi

Abstract: In 1973, a lower third molar of Gigantopithecus associated with mammalian fos-sils was unearthed in a limestone cave in Bama district of Kwangsi. The BamaGigantopithecus is of Middle Pleistocene, colltemporary to the Wuming Gigantopithecusand later than Liucheng and Hupei Gigantopithecus in age. A comparision of the lower third molar of Bama Gigantopithecus with those ofGigantopithecus from various localitis, including Bilarspur, Liucheng, Hupei andWuming, shows a tendency that the molar increased in size from Early Pleistoceneor even Middle Pliocene to Middle Pleistocene. It does not support Weidenreich'sview that the molars of Gigantopithecus had a tehdency to diminish as evolutionadvances. Tberefore, there is no strong reason to assume Gigantopithecus as a directhominid ancestor.

On the representation of every large even integer as a sum of a prime and an almost prime

Abstract: In this paper, we give a modified proof of Chen's theorem "every sufficiently large even inte- ger is a sum of a prime and a product of at most 2 primes".

Chapter 8 – automorphisms of semisimple lie algebras†

Abstract: Publisher Summary This chapter focuses on automorphisms of semisimple Lie algebras. All derivations of a semisimple Lie algebra g are inner. Clearly, g1 is a linear space and commutation is linear in regard to both elements. The group of inner automorphisms Ad g of a semisimple Lie algebra g is the component of the identity of Aut g, thus it is a closed subgroup of Aut g. The centers of Aut g and Ad q of a semisimple Lie algebra g are {e}. The chapter also discusses the group of outer automorphisms of a semisimple Lie algebra. The group of outer automorphisms of a semisimple Lie algebra g is isomorphic to a finite group G that consists of all equivalent mappings of a fundamental system of roots Π onto itself.

A theory of poggendorff illusion

Abstract: In a previous paper (Chiang, 1968), the Poggendorff illusion was explained on the basis of the optical image blurring in the retina, and other illusions of the crossing lines type have in turn been explained by the Poggendorff effect. The result of optical blurring is that when two objects are presented to the eyes, the optical image of the objects on the retina do not quite correspond to the physical shapes of the objects, and the lines AC and BC (see Fig. 1) converge before they really reach the intersection points. Thus lines BC and EH seem to be misaligned. The contribution of the optical blurring to the illusion has been experimentally verified by Coren (1969). However, many authors (for example Cumming, 1968; Pressey & den Heyer, 1968; Restle, 1969, Fame, 1970) have pointed out that the optical blurring effect alone is insufficient to explain all the feature of the illusion. Von Bekesy (1967), Ganz (1966) and Blakemore, Carpenter and Georgeson (1970) have proposed lateral inhibition as a source for the illusion; Coren (1970) has shown that when possible sources of inhibitory interactions are removed, the illusion still remains. Gillam (1971) and Gregory (1963) have used the perspective theory to explain the illusion. Weintraub and Krantz (1971) have cited evidence that the stability of vertical and horizontal orientations, and assimilation towards the vertical or horizontal also contribute to

Chapter 7 – classification of simple lie algebras

Abstract: Publisher Summary This chapter focuses on the classification of simple Lie algebras Π is said to be a simpler system if it cannot be decomposed into the union of two mutually orthogonal n subsystems For each vector in a π system Π, construct a point on the plane If the angle between two vectors is 120°, 135° or 150°, then connect their corresponding points by 1, 2, or 3 line segments, respectively The diagram obtained in this way is said to be the angle diagram of the π system Π The diagram of a π system Π is connected iff Π is a simple π system It is proved that lengths of vectors in a simple system can at most take two values and that the ratio of the squares of these two different lengths is either 2:1 or 3:1

Recherches sur le nombre des valeurs deficientes et le nombre des directions de borel des fonctions meromorphes

Abstract: Principelement sont etablies les propositions: (1) Soit f(z) une fonction meromerphe d'ordre ρ(0ρ+∞) dans le plan ouvertSi Vondesigne par p le nombre des valeurs deficientes de f(z), et par q le nombre des directions de Borelde f(z), alors on a p≤q (2) Si l'on conserve les hypotheses du(1), et suppose que ρp/2,alors on a p≤q-1

The Influence of Temperature On the Ability of Aphelenchoides Besseyi To Survive Dehydration

Abstract: Experiments with rice (Oryza sativa var. Taipei 309) florets and grains at the milk stage showed that, compared to the treatments at 20°-30° C, dehydrations at temperatures below 15° significantly reduced survival of the infecting Aphelenchoides besseyi. No difference in nematode survival was detected between the higher temperatures tested. However, in the treatments between 15°-5°, ability of the nematode to survive desiccation was progressively reduced with decreasing temperature. Investigations with nematode aggregates revealed that only the initial stages of dehydration were sensitive to chilling. Once desiccated to a certain extent at room temperature, the nematodes appeared to be no longer sensitive to subsequent dehydration at low temperatures. Nematodes in the hydrated condition were insensitive to chilling. It is suggested that lipids in the nematodes' membranes undergo phase transition which if accompanied by desiccation becomes irreversible resulting in loss of subcellular compartmentation.

Primary production in the Kuroshio current surrounding Taiwan

Abstract: Primary production in the Kuroshio current flowing around Taiwan Island was measured by using the radiocarbon method. High values of the daily primary production were found in both the aquacultural area at the western coast and the polluted area with raw rubbish heaps at the Keelung-Patoutzu coast. In the upwelling region of southeastern coast, low values of the primary production were observed. In the eastern coast, the rate of photosynthesis for an unit amount of chlorophylla under the saturated light was in the range of 1.2±0.2 mg C/mg chlorophylla/hr. Some discussions are made on the observed results.

Theory of i * -functor in algebraic topology——real topology of fiber squares

Abstract: Mathematics has for its objects of study space forms and quantitative relations in the exteriorworld. For algebraic topology in particular, the space forms involved are the various kinds oftopological spaces. Its main tools and methods consist of making correspondences usually calledfunctors to such spaces, certain kinds of quantities expressed in terms of algebraic structuresas numbers, groups, rings, algebras, etc. by means of which properties of spaces and also theirvariations are investigated. In [10],we have shown that from the theory of minimal models ofDGA-algebras due to Sullivan, we can introduce a new functor I * , which has the advantage overthe classical homotopy functor π, homology functor H, and more recently the functors J, K inbeing "calculable" in some sense and therefore easier to handle. The present paper is the detailedproofs of a part of the results announdced [10].

Chapter 9 – representations of lie algebras

Abstract: This chapter discusses the representations of Lie algebras. Representation spaces of equivalent representations have the same dimensions. Representations are understood to be linear representations. A basic problem of the representation theory of Lie algebras is to find all the representations (up to equivalence) of a Lie algebra. A representation ρ of g is said to be irreducible if the representation space V is irreducible under ρ(g) . Otherwise, ρ is said to be reducible. If a representation ρ of g is reducible, then the representation space contains a proper invariant subspace V 1 . If ρ is the direct sum of some irreducible representations, then it is said to be completely reducible. Invariant subspaces of the regular representation are ideals of g . If g is semisimple, then the regular representation is completely reducible.

Studies on the mechanism of insulin action i. the interactions op insulin and its analogs with insulin receptor

Abstract: The receptor-binding properties of insulin and its analogs with modified C-terminal peptide sequence of the B-chain have been studied in liver cells and fat cells. The results show that despentapeptide insulin has the same binding capacity as that of insulin; deshexapeptide insulin and its analog with B_(23)-glycine replaced by D-alanine have definite binding effect; desoctapeptide insulin has a very weak binding effect; the A-chain of insulin, ACTH and glucagon do not bind with insulin receptor. On this basis, the possible involvement of B_(24) aromatic ring in the binding site has been discussed and it has been proposed that the hydrophobic surface formed by B_(12), B_(16), B_(24) and B_(25) may be an important element of the binding site and the B_(20)-B_(23) U turn and A_(21)... B_(22) salt linkage may have a stabilizing effect on the hydrophobio structure, and that the binding of insulin with the receptor protein may be similar to the formation of the insulin dimer from the two monomers.

Forme mesurable de la theorie des ensembles sousliniens,applications a la theorie de la mesure

Abstract: On introduit, dans tout espace mesurable (F, ?), la notion d'ensemble ?-souslinien, distinctede celle d'ensemble ?-analitique, et la notion de mesure normale, correspondant dans le cas abstraita celle de mesure de Radon sur un espace topologique et equivalente a celle de mesure parfaite ausens de Kolmogorov-Gnedenko. On etablit, sous une forme mesurable au lieu de la forme topologi-que usuelle, la theorie des ensembles sousliniens et obtient quelques resultats nouvaux sur les ensem-bles sousliniens.

π-NUCLEUS CHARGE EXCHANGE REACTIONS

Abstract: Hadron inducced nuclear reactions are discussed by using the multiple diffractiontheory. The higher order terms are evaluated by adopting the method of separation ofvariables, which enables us to estimate the influence of the general nuclear structure configura-tions on the reaction cross sections. This method is used to obtain the amplitudes of πnucleus single- and double charge exchange reactions. The reaction cross sections forO18 (π+,π0)F18 and O18(π+,π-) Ne18 between isospin analogue states are evaluated by usingthe pure configurations of the shell model and the SU3 wave functions respectively.Theresults show that the influence of the nuclear structure on the cross sections is quiteimportant.

Two Convenient Isolation Methods for Mesophyll Cells used in Plant Cell Culture

Abstract: This paper reports two isolation methods for mesophyll cells used in plant cell culture. These methods of isolation are by hand grinding and by electro-magnetic stirring. The advantages and disadvantages of these methods as compared to the routine enzyme isolation method are discussed. Their application in protoplasts isolation and cytological researches are tested and discussed.

Chapter 13 – poincaré-birkhoff-witt theorem and its applications to representation theory of semisimple lie algebras

Abstract: This chapter discusses the Poincare–Birkhoff–Witt theorem and its applications to representation theory of semisimple Lie algebras. Let g be a Lie algebra over C and A be an associative algebra with identity 1 over C . If f is a representation from g to A and { f(g) , 1} is a set of generators of A , then A is said to be an enveloping algebra (relative to f ) of g . The uniqueness of the universal enveloping algebra is shown. The existence of the universal enveloping algebra is also shown. Always consider T / J as the unique universal enveloping algebra of g . If g is a Lie algebra and U is the universal enveloping algebra of g , then q is one-one.