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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   

2.
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.
This member of the vitamin-B complex is necessary in human diet to prevent soreness of mouth, lips and nose, and inflammation of the cornea. It is commercially produced from the fungi Ashbya gossypiiand Eremothecium ashbyii,and is used to enrich various foods and animal feedstuffs.  相似文献   

5.
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   

6.
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   

7.
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   

8.
Berlandiera is revised to includeB. subacaulis, B. pumila, B. texana, andB. lyrata with its varietieslyrata andmacrophylla. All species may be induced to interbreed readily, producing F1 progeny which are vigorous but with reduced fertility. Sympatric species produce natural hybrids which are proposed here asB. Xhumilis (=B. pumila XB. subacaulis) andB. Xbetonicifolia (=B. pumila XB. texana). All taxa investigated hadn = 15 chromosomes, including new counts forB. subacaulis and all six F1 hybrids.  相似文献   

9.
An integral equation is established applicable to many types of metabolizing systems. The equation is applied to first order chemical reactions and to some biological systems.  相似文献   

10.
The spatial variability of the photochemical efficiency of phytoplankton photosystem II was analyzed in two contrasting regions of the Black Sea: the western part of the deepwater region and a region influenced by the Danube River discharge. The fluorescence values for open (F0) and closed (Fm) photosystem II reaction centers in the investigated areas varied by an order of magnitude and correlated closely. The potential photochemical efficiency of phytoplankton photosystem II (Fm ? F0)/Fm varied from 0.16 to 0.70. Three types of the vertical distribution of this index were found. In the first type, the values increased from the surface to the top of the thermocline and then remained stable down to the bottom of the euphotic zone; in the second type, they increased from the surface to the bottom of the euphotic zone; in shallow areas, they were stable within the euphotic zone. With an increase in light intensity, the phytoplankton photochemical efficiency decreased. The light inhibition of the photosystem II efficiency was more intense in the deeper than in the upper layers of the euphotic zone.  相似文献   

11.
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   

12.
On the basis of the winter bread wheat cultivar Obryi, two independent disomic addition lines BC12F with the chromosome of the E. sibiricus St genome are created. A practical algorithm for determining the probabilities of transmission of the odd chromosome separately through male and female gametes in selfpollination of hemizygous hybrids from the equation p2–(1 + f1f4) × p + f1 = 0 is proposed, where p is the probability of the formation of viable gametes with the considered chromosome and f1 and f4 are the empirical frequencies of the corresponding homozygotes with and without the trait. The probability of transmission of an alien univalent chromosome through pollen (p) is associated with the frequency of its transmission through the egg cell (p) in backcrosses and in self-pollination (1–f4) by the equation p = 1–f4/(1–p). The calculated empirically dependent estimates of the probabilities of transmission of the added chromosome through the egg cell p = 18.7% and through pollen p = 4.3% correspond to the empirical frequencies obtained for backcrosses. The coefficients of the gamete selection V = 0.748 and V = 0.172 are calculated, and the expected segregation for the alien trait controlled by a dominant gene located in the added chromosome is determined—with the trait: without the trait is 0.222: 0.778 in F2; 0.187: 0.813 in equational and 0.043: 0.957 in certational backcrosses.  相似文献   

13.
14.
15.
The population genetic structure of plant pathogenic fungus Pyrenophora tritici-repentis was examined using microsatellite (SSR) markers. According to the geographical origin of the pathogen populations, they were designated as North Caucasian (S, 33 isolates), northwest (Nw, 39), and Omsk (Om, 43). The populations were analyzed at the nine most polymorphic SSR loci, at which 75 alleles were identified. To characterize the genetic variation within and between populations, the AMOVA algorithm as implemented in the Arlequin v. 3.5 software program was used. The number of alleles per locus ranged from 5 to 12 and their sizes varied within the range from 180 to 400 bp. The mean gene diversity at SSR loci was high for all populations (H = 0.58–0.75). The populations were considerably different in the frequencies of individual alleles of the SSR loci. Most isolates in the populations were represented by unique haplotypes. The within-population variation of the isolates at molecular markers was 86.4%; among the populations, 13.6%. Substantial interpopulation differences were found between the Om and S (Fst = 0.16) and between the Om and Nw (Fst = 0.20) populations, whereas between the S and Nw populations, these differences were small (Fst = 0.05). Thus, it was demonstrated that the population of P. tritici-repentis from Omsk oblast had the independent status of the geographical population; northwest and North Caucasian populations differed in the allelic diversity of SSR loci, and despite the low Fst value (0.05), they also belonged to independent geographical populations.  相似文献   

16.
Classic heterotaxy consists of congenital heart defects with abnormally positioned thoracic and abdominal organs. We aimed to uncover novel, genomic copy-number variants (CNVs) in classic heterotaxy cases. A microarray containing 2.5 million single-nucleotide polymorphisms (SNPs) was used to genotype 69 infants (cases) with classic heterotaxy identified from California live births from 1998 to 2009. CNVs were identified using the PennCNV software. We identified 56 rare CNVs encompassing genes in the NODAL (NIPBL, TBX6), BMP (PPP4C), and WNT (FZD3) signaling pathways, not previously linked to classic heterotaxy. We also identified a CNV involving FGF12, a gene previously noted in a classic heterotaxy case. CNVs involving RBFOX1 and near MIR302F were detected in multiple cases. Our findings illustrate the importance of body patterning pathways for cardiac development and left/right axes determination. FGF12, RBFOX1, and MIR302F could be important in human heterotaxy, because they were noted in multiple cases. Further investigation into genes involved in the NODAL, BMP, and WNT body patterning pathways and into the dosage effects of FGF12, RBFOX1, and MIR302F is warranted.  相似文献   

17.
Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is an important disease of wheat worldwide. Host resistance is the best way to control the disease. Genetic analysis of F2 and F2:3 populations from an Avocet S/Jimai 22 cross indicated that stripe rust resistance in Jimai 22 was conferred by a single dominant gene, tentatively designated YrJ22. A total of 377 F2 plants and 127 F2:3 lines were tested with Chinese Pst race CYR32 and genotyped with simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers. A linkage map was constructed with five SSR and two SNP markers. Xwmc658 and IWA1348 flanked YrJ22 at genetic distances of 1.0 and 7.3 cM, proximally and distally, respectively. The chromosomal location was confirmed using Chinese Spring nulli-tetrasomic, ditelosomics and deletion lines. Seedling reactions to 21 Pst races demonstrated differences in specificity between YrJ22 and other resistance genes on chromosome 2AL, indicating that YrJ22 is likely to be a new wheat stripe rust resistance gene.  相似文献   

18.
The reduction kinetics of the photo-oxidized primary electron donor P700 in photosystem I (PS I) complexes from cyanobacteria Synechocystis sp. PCC 6803 were analyzed within the kinetic model, which considers electron transfer (ET) reactions between P700, secondary quinone acceptor A1, iron-sulfur clusters and external electron donor and acceptors – methylviologen (MV), 2,3-dichloro-naphthoquinone (Cl2NQ) and oxygen. PS I complexes containing various quinones in the A1-binding site (phylloquinone PhQ, plastoquinone-9 PQ and Cl2NQ) as well as F X-core complexes, depleted of terminal iron–sulfur F A/F B clusters, were studied. The acceleration of charge recombination in F X-core complexes by PhQ/PQ substitution indicates that backward ET from the iron–sulfur clusters involves quinone in the A1-binding site. The kinetic parameters of ET reactions were obtained by global fitting of the P700 + reduction with the kinetic model. The free energy gap ΔG 0 between F X and F A/F B clusters was estimated as ?130 meV. The driving force of ET from A1 to F X was determined as ?50 and ?220 meV for PhQ in the A and B cofactor branches, respectively. For PQ in A1A-site, this reaction was found to be endergonic (ΔG 0?=?+75 meV). The interaction of PS I with external acceptors was quantitatively described in terms of Michaelis–Menten kinetics. The second-order rate constants of ET from F A/F B, F X and Cl2NQ in the A1-site of PS I to external acceptors were estimated. The side production of superoxide radical in the A1-site by oxygen reduction via the Mehler reaction might comprise ≥0.3% of the total electron flow in PS I.  相似文献   

19.

Key message

The shortening of Aegilops speltoides segment did not facilitate recombination between stem rust resistance genes Sr36 and Sr39 . Robustness of marker rwgs28 for marker-assisted selection of Sr39 was demonstrated.

Abstract

Stem rust resistance genes Sr39 and Sr36 were transferred from Aegilops speltoides and Triticum timopheevii, respectively, to chromosome 2B of wheat. Genetic stocks RL6082 and RWG1 carrying Sr39 on a large and a shortened Ae. speltoides segments, respectively, and the Sr36-carrying Australian wheat cultivar Cook were used in this study. This investigation was planned to determine the genetic relationship between these genes. Stem rust tests on F3 populations derived from RL6082/Cook and RWG1/Cook crosses showed tight repulsion linkage between Sr39 and Sr36. The genomic in situ hybridization analysis of heterozygous F3 family from the RWG1/Cook population showed that the translocated segments do not overlap. Meiotic analysis on the F1 plant from RWG1/Cook showed two univalents at the metaphase and anaphase stages in a majority of the cells indicating absence of pairing. Since meiotic pairing has been reported to initiate at the telomere, pairing and recombination may be inhibited due to very little wheat chromatin in the distal end of the chromosome arm 2BS in RWG1. The Sr39-carrying large Ae. speltoides segment transmitted preferentially in the RL6082/Cook F3 population, whereas the Sr36-carrying T. timopheevii segment over-transmitted in the RWG1/Cook cross. Genotyping with the co-dominant Sr39- and Sr36-linked markers rwgs28 and stm773-2, respectively, matched the phenotypic classification of F3 families. The RWG1 allele amplified by rwgs28 was diagnostic for the shortened Ae. speltoides segment and alternate alleles were amplified in 29 Australian cultivars. Marker rwgs28 will be useful in marker-assisted pyramiding of Sr39 with other genes.
  相似文献   

20.
In order to assist breeding and gene pool conservation in tropical Acacias, we aimed to develop a set of multipurpose SSR markers for use in both Acacia mangium and A. auriculiformis. A total of 51 SSR markers (developed in A. mangium and natural A. mangium x A. auriculiformis hybrid) were tested. A final set of 16 well-performing SSR markers were identified, six of which were species diagnostic. The markers were optimized for assay in four multiplex mixes and used to genotype range-wide samples of A. mangium, A. auriculiformis, and putative F1 hybrids. Simulation analysis was used to investigate the power of the markers for identifying the pure species and their F1, F2, and backcross hybrids. The six species diagnostic markers were particularly powerful for detecting F1 hybrids from pure species but could also discriminate the pure species from F2 and backcross progenies in most cases (97 %). STRUCTURE analysis using all 16 markers was likewise able to distinguish these cross types and pure species sets. Both sets of markers had difficulties in distinguishing F2 and backcross progenies. However, identifying F1 from pure species is the current primary concern in countries where these species are planted. The SSR marker set also has direct application in DNA profiling (probability of identity?=?4.1?×?10?13), breeding system analysis, and population genetics.  相似文献   

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