Showing papers by "University of Tsukuba published in 1975"

On the bed configuration in alluvial channels; their types and condition of formation with reference to bars

Abstract: Among various types of bed forms in alluvial channels, many researchers paid much effort to clarity the condition of the formation of bars, since the hydraulic characteristics of natural streams cannot be fully understood without a knowledge of basic principles that govern the formation of bars. To date, however, there has been no satisfactory explanation for the formation of various types of bars. Through the flume experiments, the author recognized 4 types of bed configuration de-fined by bar development, each of which appears according to the different hydraulic regimen (Ikeda, 1973). In this paper, the author attempts to classify the configuration of alluvial channels into these 4 types and examine the condition of bar formations, using the same parameters as in the flume experiments. The lower Omoi River, Tochigi Pref., was chosen for a study area where a detailed field observation was made along 4 reaches (from No. 1 to No. 4 in down-stream direction, Figs. 1 A, 2 B) which represent above mentioned 4 types of bed configu-rations respectively. No. 1 reach: corresponding to Type 1; The type of multiple bars, consisting of a set of linguoid and diagonal bars, is generally regarded to be features of channels of low sinuosity, with high width-to-depth ratio and steep slope. At low flow, higher parts of each bar emerge as mid- and side-shoals, dividing the stream (Fig. 5). These bars correspond to braid bars (Allen, 1968), spool bars (Krigstrom, 1962) and channel bars (Thornbury, 1954). Figures 10, 11 and 18 show the features of similar channel configuration. No. 2 reach: corresponding to Type 2; The type of alternate bars, consisting of diagonal bars with sharp crest lines which migrate downstream (Fig. 6). A sharp avalanche face of their downstream edge and abrupt change of talweg from one side to the other constitute a characteristic feature of this type of bed configuration. At low flow, because of the alter-nate arrangement of side shoals, alternation of riffles and pools are seen. No. 3 reach: corrresponding to Type 3; The type of alternate bars, consisting of diagonal bars with obscure crest lines, often arises in channels of sandy bed. It resembles to type 2 in plan (Fig. 7), but relief of bars is much smaller, therefore riffles and pools do not appeareven at low flow, and talweg meanders continuously from one bank to the other. No. 4 reach: corresponding to Type 4; No bars are formed. Although alternate de-pressions are formed at low flow even in the straight No. 4 reach (Fig. 8), the maximum relief in the bed is less than 50 cm. It is regarded, therefore, that bars are not created in such channels of gentle slope and very small width-to-depth ratio, as channels of delta plain (See also Figs. 12 & 14). The median grain size of bed materials in the upper part of the study area is 10_??_20 mm in diameter, while at 14 km below the junction of Sugata River, it decreases suddenly to 1 mm (Fig. 2 B). And the channel slope decreases downstream in accordance with the change of grain size of bed materials mentioned above (Fig. 2 A). Further, the channel configuration of the lower Omoi River also changes downstream accordantly to the decrease of channel slope and grain size of bed materials (Figs. 3 & 4). This relation is schematically illustrated in Fig. 9. In order to clarify the hydraulic conditions of formation for each 4 types of bed configu-ration, two parameters, U*/ U*c (flow intensity) and S•W/D (channel form index) were obtained by dimensional analysis based on similarity-law of distorted models. Here U* is shearing velocity at bed, U*c is critical shearing velocity for bed materials, S denotes slopes, and as the channel forming discharge is here approximated by the bankfull discharge, the bankfullwidth and -depth are used for W and D respectively (Table 1).

Heterogeneity of the minimum functional unit of hemocyanins from the spider (Argiope bruennichii), the scorpion (Heterometrus sp.), and the horseshoe crab (Tachypleus tridentatus).

Abstract: The heterogeneity of arthropod hemocyanins was studied by polyacrylamide gel electrophoresis and immunochemical techniques. The spider (Argiope bruennichii), the scorpion (Heterometrus sp.), and the horseshoe crab (Tachypleus tridentatus) were found to have 4, 5, and 5 minimum functional units of hemocyanin, respectively, the apparent molecular weights of which were 79,000, 81000, and 80,000, respectively, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Application of the Gutzwiller Method to Antiferromagnetism

Abstract: The method of Gutzwiller in the problem of electron correlation in the Hubbard model / is extended to the antiferromagnetic state It is shown that the transition from the para­ magnetic to the antiferromagnetic state occurs at a certain value of U (intraatomic Coulomb energy) for a fixed value of the electron concentration In contrast to the result in the Hartree-Fock approximation, this ~alue of U does not vanish even in the case when the magnetic zone boundary coincides with the Fermi surface For extremely large values of U, the critical electron concentration is shown to approach to 1/2 Special care is taken in the case of the half-filled band, and our ground state energy is compared with that in the Hartree-Fock approximation It is shown that for large value of U the Hartree-Fock energy is lower, but that for intermediate value of U our energy be­ comes lower for the special band structure

Giant olivine chondrule as a possible later-stage product in the nebula

Abstract: ABUNDANCES of trace elements, in particular, of rare-earth elements (REE) in the Allende Chondrite and its inclusions have attracted increasing attention from geochemists1–4. Based on the abundance characteristics of major elements and trace elements (including REE), Martin and Mason3 distinguished four distinct groups among the aggregates and chondrules of the Allende Meteorite. We report here on the presence of an olivine chondrule in Allende with REE abundance features quite different from those of any inclusions previously reported.

Partial Structure of a Spore Germination Inhibitor from a Cellular Slime Mold, Dictyostelium discoideum

Abstract: The partial structure of a spore germination inhibitor from a cellular slime mold, Dictyostelium descoideum was investigated. The molecular weight of this substance is 412 daltons. It contains at least N-(3-methyl-2-butenyl)adenine and an unknown α-amino acid residue. At the concentration of ~0.03 μg/ml (~10−8m), this compound completely inhibited the spore germination of this organism.

Effects of calcium ionophore (A-23187) on glucose oxidation and iodide transport in dog thyroid slices.

Abstract: A calcium ionophore (A-23187, 20 mug/ml) stimulted 14C-1-glucose oxidation in dog thyroid slices to an extent equivalent to that obtained by the optimal concentration of dibutyryl cyclic AMP (1mM). Furthermore, the ionophore augmented the stimulation by dibutyryl cyclic AMP much more than the simple additive effect. The ionophore also enhanced the effect of TSH, but to a lesser extent. Under conditions where organic binding was blocked, T/M ratio of radioiodine concentration was lowered in slices by the ionophore; the findings similar to those obtained with TSH and dibutyryl cyclic AMP. The ionophore exhibited a slightly depressive effect on the basal cyclic AMP level. The elevation by TSH of cyclic AMP levels was also slightly depressed by the ionophore, but statistically insignificant in most cases. These results indicate that calcium ion may play an important role in the TSH regulation of iodide transport and glucose metabolism in the thyroid, in some cases by augmenting the effects of cyclic AMP.

On the structure of commutative affine group schemes over a non-perfect field

Abstract: Let k be a non-perfect field of characteristic p>O with a p-basisB and ks the algebraic separable closure of k. Starting from the ring of Schoeller D B [3] and the topological Galois group II of ks over k, we construct a new ring Ф such that the category of commutative affine k-group schemes is anti-equivalent to the category ofeffaceable left Ф-modules. (The effaceability is defined in the text).

Gentzen-type formal, system representing properties of function and its implementation

Abstract: We describe a theorem-prover (called TKP 1), which is based on a Gentzen-type formal system (14). TKP 1 can directly deal with functionals and the composition of functionals, it comprises the fixed point operator and a kind of facility for induction. Let us attempt to prove P(F(x, y)) for F(x, y) such that F(x, y) =Vn-0∞ fn(x,y) Provided that P(F(x, y)) can be obtained from P ffn(x, y)) n = 0, 1, 2,.,., TKP 1 automatically gives the induction hypothesis P (fn (x, y)), and then prove P(fn-1, (x, y)). It. can efficiently make proving procedure for properties of recursive programs. We can supply assumptions and definitions at will. TKP 1 displays an easily read proof-figure.

Hypoelliptic Degenerate Evolution Equations of the Second Order

Abstract: For degenerate parabolic differential operators, the study of hypoellipticity has been made by many authors (see [1]~[9]). But for degenerate ]?-parabolie differential operators, its study has not been made so detailed (see F. Treves [10]). So we shall give a sufficient condition for the operator given by (0.1) to be hypoelliptic by constructing very regular parametrices of the operator (see Y. Kato [2], T. Matsuzawa [8]). The operator considered here is a special one, but we want to give an elementary relation between the order of degeneracy of the co-

On the areal variation of land and its utilization patterns in the state of praiba, northeastern brazil

Abstract: This paper is an approach to the analysis of land and its utilization patterns in Northeastern Brazil. It was based on the field observations of the multiple relationship existing between natural environment and human activities. The Department of Geography, Tokyo Kyoiku University, planned a field study of Northeastern Brazil, and sent the research missions to this area three times, sponsored by the Japanese Ministry of Education. The first field study was carried on from December, 1966 to February, 1967, the second from January to March, 1971, and the third from December, 1972 to February, 1973. This report outlines the results of field observation in the third field study, mainly in the state of Paralba. Many geographers have established the areally corresponding relationship between natural environmental factors and land use. Our research group, including myself, proposes a division of land use regions in the state of ParaIba. This consists of three regions and ten subregions as follows: 1) Zona da Mata a) Coastal lowland. b) Tabuleiros. c) Varzea (Rio de Acucar). 2) Agreste d) Peripheral Tabuleiros. e) Depression Zone (low relief plain formed on crystaline rock). f) Borborema Massif. g) Brejos. 3) Sertao h) Cariris. i) Piranhas basin. j) Alto-Sertao.

Effect of Glucose Adenosine on 3', 5'-Monophosphate Levels in Rat Pancreatic Islets

Abstract: Time course of the changes in insulin release and cyclic AMP levels in isolated rat islets incubated in media containing 5 or 16.7 mM of glucose were followed. The higher glucose concentration caused a slight but significant increase of cyclic AMP levels after 10 min incubation, but not 5 min incubation, whereas the stimulation of insulin release by 16.7 mM of glucose was apparent in both incubation times. Theophylline increased cyclic AMP levels markedly but did not stimulate insulin release when the glucose concentration was 5 mM. A slight augmentation by theophylline of insulin release was observed in the incubation medium containing 16.7 mM glucose. All these findings suggest that the elevation of cyclic AMP in islets may not play a role for the initiation of the insulin release induced by glucose, though it may act to modulate the glucose effect.

Determination of Paleotemperature by the Oxygen Isotope Analysis

Abstract: The oxygen isotope technique introduced since last two decades, has become more extensively used than any other geochemical technique for paleotemperature determination. In this paper, representative studies using this technique and the principle of the method are briefly presented and problems posed directly and indirectly from this technique are discussed. In 1947, H. C. UREY found that the ratio of stable oxygen isotopes in calcium carbonate varies with temperature at which this carbonate is produced from water. He suggested that the variation in isotope concentration can be used as a geological thermometer. UREY et al. (1951) first published a paper on paleotemperature determination. Since then many paleotemperature measurements have been published by various workers who used calcium carbonate-bearing fossil as basic materials. Few paleotemperature data from the Paleozoic Group are available at present. Those of Mesozoic paleotemperature are given by BOWEN (1966, et al.) and many other workers. As the result of the values of the Mesozoic temperature based on the belemnite shells collected from various localities in the world, the paleotemperature trend in Europe differs from those in Australia. The Tertiary temperature is known only in Australia (DORMAN, 1966), New Zealand (DEvEREux, 1967), and Northwest Pacific (DOUGLAS et al., 1971). The paleotemperature change in the Quaternary was discussed by many workers. Among others, EMILIANI (1966) showed the generalized climatic curve during these 450,000 years. The middle Pleistocene temperature in the Boso Peninsula is calculated by the writer and his colleagues based on the oxygen isotopic composition of the pelecypod shell. The results give the temperature ranging from

Classification and Chronology of Monthly Mean Topography Patterns at the 100mb-Level in the Northern Hemisphere

Abstract: An attempt was made to classify the monthly mean topography patterns of the 100mb-level in the Northern Hemisphere from January 1956 to December 1970. The winter types are classified into eight by the range and height of circumpolar low pressure and by the range and height of high pressure area in middle or lower latitudes. The summer types are classified into five by the absolute height of anticyclone in the Eastern Hemisphere and its latitudinal range. According to this classification criteria, the chronology was made and the normal annual change of the types was shown. Lastly, discussions about the relations between the types at the 100mb-level and at the 500mb-level, 50mb-level and 10mb-level are presented. It was made clear that some winter types at the 100mb-level have a close relation to the zonal or meridional circulation types of the 500mb-level. A positional relation of the centers of the circumpolar low pressure was found between the 50mb-level and 100mb-level. Among the relationships as far as analysed, the phenomena shown as the topography patterns at the 100mb-level occur earlier than those shown as the circulation type at the 10mb-level with some exception.

Lamb-Shift Polarized Ion Source with Spin Filter

Abstract: Performances of our 1st Lamb-shift polarized ion source with spin filter was reported in the Conference held at Brookhaven National Laboratory in 1971. Here we present the design of the 2nd polarized ion source of the same type, which will be operated in connection with the 12UD Pelletron tandem accelerator of University of Tsukuba.