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The structure of natural languages as studied by linguists is connected in several ways with phenomena outside this domain. Problems of this kind are, to mention only three: (a) the acoustical and physiological interpretation of the primitive elements in which the sound structure is represented; (b) the conceptual or referential interpretation of the primitive elements that build up the meanings of the utterances; (c) the structural relationships that go beyond the single sentences, usually taken as the largest units to be analyzed linguistically, i.e., the question as to the conditions that two or more sentences must meet in order to form a connected text. ...
Continuum structure of Ca40
(1967)
The total S1- matrix of Ca40 has been calculated for excitation energies between 11 and 28 MeV. As typical results, the (γ, p0) and the total absorption cross sections are shown and compared with experiments. It is shown that the proper treatment of the one-particle, one-hole shell-model continuum accounts for most of the observed structures.
The theory of collective correlations in nuclei is formulated for giant resonances interacting with surface vibrations. The giant dipole states are treated in the particle-hole framework, while the surface vibrations are described by the collective model. Consequently, this treatment of nuclear structure goes beyond both the common particle-hole model (including its various improvements which take ground-state correlations into account) and the pure collective model. The interaction between giant resonances and surface degrees of freedom as known from the dynamic collective theory is formulated in the particle-hole language. Therefore, the theory contains the particle-hole structures and the most important "collective intermediate" structures of giant resonances. Detailed calculations are performed for 12C, 28Si, and 60Ni. A good detailed agreement between theory and experiment is obtained for all these nuclei, although only 60Ni is in the region where one would expect the theory to work well (50< A <110).
The ribonucleic acid of reovirus was extracted with 2 M sodium perchlorate solution and spread by the protein monolayer technique. Areas of the monolayer were transferred to support films, rotary shadowed, and observed in the electron microscope. Filaments of RNA obtained by extraction prior to spreading were similar in appearance and in distribution of contour lengths (0.2 to 1.2 μ) to those obtained by phenol extraction of the virus. Most of the filaments resulting from extraction of the virus suspension during spreading on a sodium perchlorate solution, however, were longer than 1 μ. The lengths of the longest filaments exceeded the 5 μ length predicted from chemical data for one single piece of complementary-stranded RNA in the reovirus particle.
The short filaments, 1.2 μ and less in length, fell into a tri-modal pattern of length distribution with peaks at 0.35 μ, 0.60 μ and 1.10 μ. These shorter lengths probably resulted from breakage of the intact RNA during the extraction procedures. The consistently observed pattern of length distribution suggests that they represent relatively stable subunits of the molecule.
Sodium perchlorate extracted reovirus RNA was thermally denatured in formaldehyde prior to spreading by the protein monolayer technique. Length distributions and relative numbers of filaments in the peaks of the tri-modal distribution pattern were similar to those found for unheated material when extracted prior to spreading. This similarity indicates that heating subsequent to extraction produced no further filament breakage. The thin, kinky appearance of the heated filaments, and the appearance of congruent pairs, indicated that heating had separated the strands of the complementary-stranded RNA subunits.
Fly larvae of the Anthomyiidae, Muscidae, Calliphoridae, and Sarcophagidae are scavengers and breed in filthy material such as animal dung, human feces, dead animals and decaying vegetables. Therefore, the presence of these larvae in our environment indicates defective sanitary conditions, and offers many problems from the standpoint of public health. Clinically, the larvae of some species cause myiasis in man and animals. On the other hand, in the field of legal medicine postmortem time of dead bodies is estimated in some cases by the species and age of larvae collected from them. Thus, the fly larvae are closely associated with our lives. Morphologic studies on larval stages of flies were started in the beginning of this century by Portchinsky (1910), Banks (1912), MacGregor (1914), and Keilin (1915 and 1917). Portchinsky first described chiefly the habits and metamorphosis, and later MacGregor emphasized structure of posterior spiracles in the identification of the larvae. Keilin (1917) discovered and emphasized the importance of the characteristic structures such as the cephalopharyngeal sclerite, anterior and posterior spiracles and other external and internal characters. Following them, many authors made comparative and systematic studies of fly larvae and there are many reports of such research. However, morphology, taxonomy and ecology of these fly larvae have not been studied systematically in Japan. During the period from 1915 to 1936, 10 or more accounts were made about fly larvae that caused intestinal myiasis in man. In 1937, Kodama and Yasuda reported Ophyra nigra Wied. asa cause of intestinal myiasis. Yasuda (1939) reported 12 species of fly larvae in Seoul, Korea with detailed drawings and descriptions. Lopes (1943 and 1946) reported sarcophagid larvae from Neotropical region. Hall (1947) described calliphorid larvae from North America in his publication "The blow flies of North America". In 1951, Roback used the characters of the larvae such as pharyngeal sclerites and posterior spiracles for the classification of the Calypterate, Diptera. In the same year, Zimin reported Russian muscoicllarvae in his publication "Fauna USSR, Muscidae" using the external characters such as spines, papillae, and anal plate on the body surface as well as anterior and posterior spiracles and cepahlopharyngeal sclerite. Fan (1957) reported some filth fly larvae from China. In Japan, Kana et a!. (1950-1958) described larvae of 39 species belonging to 4 families. In the present paper, the author describes 3rd stage larvae belonging to 70 species in 33 genera of 4 families. In addition, photographs of internal and external structures and keys to families and species of 3rd stage larvae are given. Moreover, 6 species belonging to Muscidae and 1 species ofSarcophagidae for which the larvae were not seen are cited from the descriptions and figures published by Keilin (1917), Zimin (1951), Kano and Sato (1951), and Fan (1957). Those species are also included in the keys of this paper.
LANGEVIN equations of the type dn× (t)/dtn+...+c × (t)=K (t) constitute the starting point of a phenomenological fluctuation theory of irreversible processes. These equations are not constructed from transport equations (as in the older theory), but via a generalized MASTER equation from phase space mechanics. The MARKOFF processes of first and higher order defined by the various LANGEVIN equations are studied by the prediction theory of stationary stochastic processes. Instead of the variation principle of the ONSAGEB–MACHLUP theory one has the minimization of the prediction error. The mean relaxation path and the entropy of the considered processes are calculated. It is shown that the entropy consists of one part which is given by the relaxation path and another which is determined by the prediction error.
Using the eigenchannel reaction theory we performed coupled-channel calculations for Si28 and computed the differential cross section for Al27(p, γ0)Si28 over the energy range 6 MeV<Ep <16 MeV. The obtained angular distributions are nearly constant over the whole energy range and agree with the experiment in that they are almost isotropic. Thus, it seems that in this framework we can give a natural explanation for the peculiar behavior of the Al27(p, γ0)Si28 cross section.