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1.
In this treatise the author describes two species from the Lias, and four from the Dogger. One liassic species is already known (Reinholdella macfadyeni [Ten Dam]) from the Upper Lias (Bifrons-Zone), England, the other one was found by Dr.Bartenstein in Luxemburg, Lias δ Grenze ε, and has been namedReinholdella pachyderma nov. spec. The species from the Dogger areReinholdella dreheri (Bartenstein) and three new species, viz.Reinholdella brandi nov. spec.,Reinholdella ornata nov. spec. andReinholdella epistominoides nov. spec. The genusReinholdella has obviously derived from the genusConorboides Hofker (1951) and the speciesR. epistominoides proves that the genusEpistomina is related withReinholdella. It may be thatReinholdella is related withAsterigerina; but the large gap in the Cretaceous, where noReinholdella is found nor any species ofAsterigerina, contradicts this view.  相似文献   

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Tests ofEpistomaria semi-marginata (D’ORBIGNY) are analysed; a complicated toothplate is present and the marginal foramen is homologised with that ofEpistomina, whereas the supplementary sutural foramina are connected with the toothplate also. The taxonomy of the Epistominidae can be established on the basis of the development of the toothplate inReinholdella, Epistomina, Epistomaria, Cushmanella, Pseudobulimina, Robertina andRobertinoides. Species with coarse pores, double septal walls, spaces between which form supplementary chambers closed ventrally by porous plates, and lacking a toothplate in the chambers do not belong toEpistomaria but are closely allied toGavelinella from the Upper Crateceous. They are joined in the genusEpistomaroides Uchio. Two of them,E. separans (LE CALVEZ) andE. punctata (SAID) are analysed in this paper. The type-species,E. polystomelloides has been analysed 1927 (Siboga I, p. 35–37, Tafel 16, Fig. 1–6).  相似文献   

3.
Electric impedance measurements on systems consisting of nonuniform elements (e.g. nerve bundles, cell suspensions, imperfect dielectrics)_can be interpreted if the impedance characteristics of the individuals and their impedance distribution are known. Conversely, given the observed overall impedance,z(p), the impedance distribution of the individuals is not uniquely determined in both phase angle and static capacitance. If all individual phase angles are equal, the distribution,D(τ), is the solution of Stieltjes' integral equation
$$F[z(p)] = \int_0^\infty {\frac{{D(\tau )d\tau }}{{1 + p\tau }}} ,$$  相似文献   

4.
E. Karrer 《Protoplasma》1933,18(1):475-489
Muscle belongs to a class of highly elastic gels typified by rubber. Results of studies of certain properties of gels seem applicable.
  1. 1.
    The change of fluidity with temperature is logarithmic: log φ=A?Q/TT is absolute temperature. The change of the constants with concentration and mastication suggests that rubber contains long filamentous molecules.  相似文献   

5.
The isometric length-tension diagram for individual fibers and for whole muscle is considered, and it is proposed that the tensionp may be represented for any muscle whose fibers are parallel and not in series, in the form
$$p = f\left( x \right) + \beta \phi \left( {\alpha ,l,x} \right),$$  相似文献   

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Author cultivated fermenting cells (Scccharomyces spec.) in must of grapes and measured the various vital phenomena. The data thus received described in a rectangular co-ordinate as a function of time, found three kinds of characteristic curves in every vital phenomenon (whether belonging to the group of feeding, growth or that of increase): I. the curve described bySachs in 1873 and called the curve of the great period of evolution (Fig. 1:s). 2. the one described byM. G. Harting in 1845, and the curve of individual or ontogenetic evolution (Fig. 1:S). 3. the undulatory curve similar to a sinus-cosinus function, deduced in theory by author and later on, in 1915, also found on an experimental basis (Fig. 3). — Analysing these curves, author demonstrates that they are in the closest relationship with each other. The course ofSachs' great period is identical with the function of the aperiodically mitigated vibromotion; the course ofHarting's ontogenetic curve is identical with the integral of the previous aperiodic function; the undulatory curve discovered by the author, and the one belonging to the philogenesis of evolution, consist of two details, one of the members is formed from the function of aperiodically mitigated vibromotion, and the other from a function of periodically mitigated vibration. — Mitigated vibromotion, according to our present knowledge can only arise if a body capable of vibration is simultaneously affected by a force establishing movement and a resistance mitigating the movement. In the living organism, on this basis, there is also a force and a resistance. The living organism obtains this force from food while the resistance is rooted in the construction of the cell. The author proves that the cells which no longer divide (the so-called permanent tissueforming cells) follow an aperiodical vibromotor course in their development while in the development of the continually dividing, so-called meristematic cells, owing to the periodic change of division and regeneration, the potential of the energy accommodates itself to the periodic vibromotor course. Both forms of development are derived from the identical differential equation: d2s/dt2=?w2s?2r ds/dt, the only difference between the two phenomena is that by aperiodic oscillation it is r2>w2 while by periodic it is r22 and this brings about the difference in the development of the cells. Thus the laws of ?biomotoric energy” following vibromotion constitute the most general law in living organism. The organism lives as long as the biomotoric energy is active, if the action of this energy ceases, death ensues. The most essential result of this research work is that we have become acquainted in regard to both cases with the w, r, v0 factors regulating the qualities of two chief types of living cells, the meristematic and those incapable of division as in these equations, the constants changing according to the biological conditions, and that we can accurately follow the course of the phenomena with the method of theoretic physics and furthermore, that we have found the connection between these two chapters of evolution.  相似文献   

8.
Etiolated plants must be irradiated before chlorophyll can form in them. Chlorophyll develops most readily in young irradiated plants. More carotene develops in seedlings grown from young seeds than in seedlings grown from older ones. There may be a relationship between the viability of seeds and the potential power to produce carotene. Carotinoid-pigment formation precedes chlorophyll formation. Probably some necessary substance is translocated in the plant for the formation of pigment. Carotene and xanthophyll may be precursors of chlorophyll. They probably form a respiratory mechanism for the plant. Carotene may be a precursor of auxin.  相似文献   

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