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1.
Douglas Snow 《The Annals of applied biology》1945,32(1):40-44
Isolations were made of mould species actively growing on a variety of feeding stuffs stored at fixed humidities between too and 65% for periods of up to 4 years. The factors influencing the species of moulds isolated were: (1) die relative humidity of the atmosphere; (2) the length of the storage period before the isolations were made; (3) the type and origin of die feeding stuffs from which the isolates were obtained.
A critical humidify existed for each species below which the development of mould spores could not take place. At relative humidities (R.H.) between 100 and 90% a large variety of moulds were able to develop. Members of die Mucorales and the Fungi Imperfecti were not isolated below 90% R.H. and, although ***Pemicillium app. flourished between 100 and 85% R.H., they were not isolated below 75% R.H. ***Aspergilhes app., on the other hand, were able to develop under conditions of very restricted moisture supply. Some members of the A. ***glaucus group were able to grow at humidities as low as 65-70%.
In general, the moat commonly occurring moulds on the feeding stuffs used in these trials were small ***ascospored species of the A. ***glaucus group, particularly A. ***repens and A. ruber. It is considered that it is these species that will most frequently cause mould damage to feeding stuffs in commercial stores. 相似文献
A critical humidify existed for each species below which the development of mould spores could not take place. At relative humidities (R.H.) between 100 and 90% a large variety of moulds were able to develop. Members of die Mucorales and the Fungi Imperfecti were not isolated below 90% R.H. and, although ***Pemicillium app. flourished between 100 and 85% R.H., they were not isolated below 75% R.H. ***Aspergilhes app., on the other hand, were able to develop under conditions of very restricted moisture supply. Some members of the A. ***glaucus group were able to grow at humidities as low as 65-70%.
In general, the moat commonly occurring moulds on the feeding stuffs used in these trials were small ***ascospored species of the A. ***glaucus group, particularly A. ***repens and A. ruber. It is considered that it is these species that will most frequently cause mould damage to feeding stuffs in commercial stores. 相似文献
2.
Summary A newSalmonella type (S. haarlem) with the antigenic formula 9,12: z: e,n,x, is described. *** DIRECT SUPPORT *** A1365006 00016 相似文献
3.
Michael Nee 《Brittonia》1982,34(1):85-88
Solanum citrinum from northeastern Mexico is described, figured and discussed. *** DIRECT SUPPORT *** A01CT119 00006 相似文献
4.
Robert W. Schery 《Economic botany》1947,1(1):20-25
A plant which in one form contains deadly prussic acid and in other forms nourishes thousands of primitive people and furnishes tapioca to modern man. *** DIRECT SUPPORT *** A02QO001 00002 相似文献
5.
Cytochalasin D, an inhibitor of actin polymerization, interferes with ascogonial differentiation in the fertilefluffy mutant ofNeurospora crassa. As the total level of actin and its mRNA remain unchanged, this suggests that it is in its microfilamentous form (F-form)
that actin is stringently required for female differentiation. *** DIRECT SUPPORT *** A00EN042 00011 相似文献
6.
Dagmar Dykyjová 《Folia Geobotanica》1979,14(3):267-325
A comparative review of the elementary chemical composition of aquatic vascular plants is presented together with the author’s own results. Attention is focussed on the specific genotypic, onthogenetic and between-organs variability of the selective uptake and accumulation of mineral ions in macrophytes in relation to trophic conditions of habitat. The concentration factors and atomic ratios are also considered. Numerical tables presenting comparative data are arranged alphabetically according to plant species, with indications of geographical situation, phenology, part of plant tissues analyzed, nutrient status in biotopes and appropriate bibliography. *** DIRECT SUPPORT *** A01DO054 00003 相似文献
7.
Jiří Soják 《Folia Geobotanica》1971,6(2):217-219
Einige alpine, balkanische, mediterrane und kaukasische Arten der GattungHieracium werden in die GattungPilosella versetzt. Es werden 60 neue nomenklatorische Kombinationen vorgeschlagen. *** DIRECT SUPPORT *** A01DO021 00005 相似文献
8.
Barbara Ertter 《Brittonia》1988,40(4):398-399
A new variety,Ivesia aperta var.canina, is described from Dog Valley, Sierra County, Nevada. It differs from the typical variety and approachesI. sericoleuca in its larger, paler yellow petals; longer filaments and styles; and decumbent-ascending vs ascending-erect stems. *** DIRECT SUPPORT *** A01CT146 00004 相似文献
9.
LARS RAMSKÖLD 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1988,21(4):307-318
New material of early growth stages of the Silurian (Llandovery) trilobite Acernaspis is described. Pre-adult ontogenetic stages of this genus closely resemble adults of the post-Llandovery genus ***Ananaspis. A heterochronic descent of Ananaspis from Acernaspis is proposed. ***Ananaspis is interpreted as pae-domorphic, having arisen largely through neoteny. Neotenic changes already appear in the lineage in the last Acernaspis species, and Ananaspis then underwent continuous ncotcnic change throughout its known Silurian history. ▭ Heterochrony, neoteny, Silurian, Trilobita, Phacopidae, Acernaspis. Ananaspis. 相似文献
10.
Epinigericin toxicity towards Tetrahymena pyriformis GL; changes in cell volume and intracellular pH
A study of the toxicity of epinigericin, an antibiotic ionophor, towards the ciliate Tetrahymena pyriformis showed that this molecule stopped cell division, increased cell volume and led to a more basic intracellular pH. The action of epinigericin was probably linked to its function as an ionophor. The ionic selectivity of this molecule is still not known. The raising of the intracellular pH of ciliates by this antibiotic may be linked to its toxic action and its ion-transport mechanism in Tetrahymena. *** DIRECT SUPPORT *** AG903066 00009 相似文献
11.
The energy charge ofAzotobacter vinelandii was measured and found to be poised at a value of 0.3. This value was expected in view of the rate of oxygen consumption
observed in these resting cells. Adenine nucleotides and poly-β-hydroxybutyric acid were also determined and the relative
amounts of these were used as a basis for speculation on long term survival ofAzotobacter cysts in soil. *** DIRECT SUPPORT *** A01R4012 00003 相似文献
12.
Eva Papastergiadou Spyros Dafis Panayotis Dimopoulos Thalia Lazaridou 《Folia Geobotanica》1997,32(3):335-341
A review of the vegetation of Greece, following the hierarchical system of four main syntaxonomic levels (association, alliance, order, class) is presented and the correspondence of the high-ranked syntaxa with the Habitat Types included in Annex I of the Directive 92/43/EEC has been prepared. The syntaxonomic list of the vegetation units of Greece (up to alliance level) is composed of 41 classes, 56 orders, and 91 alliances. Of the 226 Habitat Types listed in Annex I of Directive 92/43/EEC, 111 different Habitat Types are present in Greece, of which 26 are Priority Types. The establishment of a syntaxonomic typology for the Habitat Types recorded in Greece is essential for the sake of vegetation mapping and nature conservation. A habitat coding system, as applied in Spain, is proposed for Greece for mapping purposes. *** DIRECT SUPPORT *** A02DO015 00007 相似文献
13.
14.
N. Rashevsky 《Bulletin of mathematical biology》1949,11(1):15-17
When the functionQ in the equation ∇2c +Q(c) = 0 is positive and is of a specified kind, the equation admits of a centrally spherical solution such thatc is positive everywhere, tending to zero at infinity anddc/dr=0 atr=0. Physically this corresponds to a local concentration of the solute in an infinite medium without any membranes present.
This result would indicate the possibility of the formation of spontaneous concentrations and non-uniformities in non-linear
diffusion fields. Possible biological implications are mentioned. *** DIRECT SUPPORT *** A01E2041 00002 相似文献
15.
Leo Marx 《Journal of the history of biology》1992,25(3):449-468
Conclusion Recent anxieties about the deterioration of the global environment have had the effect of intensifying the ambiguity that surrounds the social roles of scientists and engineers. This has happened not merely, as suggested at the outset, because the environmental crisis has made their roles more conspicuous. Nor is it merely because recent disasters have alerted us to new, or hitherto unrecognized, social consequences of using the latest science-based technologies. What also requires recognition is that ideas about the social role of modern science and engineering are embedded in, hence mediated by, larger views of the world. Within such American worldviews, moreover, the status of science and engineering is closely bound up with their perceived effect upon the environment.In the dominant culture, accordingly, the respect given to scientists and engineers is in large measure dependent on their ability to play the central role assigned to them in the historical narrative about progress. As the ostensible heroes of that popular story, they are expected to lead the way in realizing the promise of prosperity and general well-being. The environmental crisis surely has diminished the credibility of that story, thereby causing the social role of science and engineering to seem more dubious — more ambiguous. To be sure, the crisis also may have the effect, for very different reasons, of increasing the power and responsibility of organized science. But the late twentieth-century task of damage control cannot possibly elicit anything like the respect accorded to organized science by the earlier belief in progress.It also is important to recall, finally, that the narrative of progress itself has undergone a disillusioning transformation. The early Enlightenment version of the story depicted scientists and engineers working in the service of a social and political ideal that all people could share. But the later technocratic concept of progress, with its sterile instrumentalist notion of advancing the power of science-based technology as an end in itself, is far less likely to inspire trust. Its patent inadequacies have had the effect of enhancing the appeal, if only by contrast, of the seemingly anti-science ideologies of pastoralism and primitivism. All of which might be taken to suggest that if the scientific and engineering professions want to recover some of the respect and status they once had, they would be well advised to join with sympathetic humanists and social scientists in recuperating some of the idealism that the project of modern science formerly derived from its place within the ideology of progress. That might entail the sacrifice of their technocratic posture of neutrality, dissociating themselves from people and institutions responsible for environmental degradation, and their help in formulating a new concept — which is to say, new criteria — of progress to which they might commit themselves. A primary test of any proposed social policy under this new dispensation surely would be whether it would improve, or at a minimum protect, the life-enhancing capacities of the global ecosystem. *** DIRECT SUPPORT *** A8402064 00011 *** DIRECT SUPPORT *** A8402064 00012 *** DIRECT SUPPORT *** A8402064 00013 相似文献
16.
Effect of nickel and aluminium was studied on aflatoxin and lipid production by two strains ofAspergillus flavus in a sucrose—asparagine—salts medium. Inclusion of aluminium in the medium established an inverse relationship between aflatoxin
and lipid production. At lower concentrations aluminium stimulated aflatoxin production, whereas at higher concentrations
it stimulated total lipid production. Nickel at higher concentrations resulted in an increase in total aflatoxin production.
However, no definite correlation was observed between total aflatoxin and total lipid production when nickel was included
in the medium. *** DIRECT SUPPORT *** A00FP116 00002 相似文献
17.
Zdenko Polák 《Biologia Plantarum》1965,7(5):363-367
Investigating weeds for viruses in ruderal localities of Greater Prague two forms of mosaic diseases inSisymbrium loeselii Jusl. were demonstrated (green and yellowish-green mosaic). Transmission tests carried out on differential host plants showed that the green mosaic is caused by cabbage black ringspot virus (CBRV) and the yellowish green by mixed infection of CBRV and tobacco mosaic virus (TMV). TMV—isolate is characterized as an unusual necrotic strain; its capability to reproduce in cruciferous plant in nature is unique. It was ascertained that green mosaic was commonly spread overSisymbrium plants in ruderal ***DIRECT SUPPORT *** A01GP029 00004 associations on Prague territory; epidemiological significance of this discovery is discussed. 相似文献
18.
Susan M. Billings 《Journal of the history of biology》1971,4(2):275-305
Conclusion It was thus the combination of observational and experimental approaches that ultimately led to confirmation of the outgrowth theory. The observational method was essential for defining various possible methods of nerve fiber development. The multicellular, protoplasmic bridge and outgrowth theories were each postulated to explain purely observational evidence. However, the lack of truly suitable equipment and techniques to study the developing nervous system made it impossible to agree on a single theory on this basis alone. The experimental method provided a means of choosing between these theories. Without the preceding observations that had led to the formulation of various hypotheses, however, the experimental approach might not have been so successful, for the power of this method is more of selection than of generation.Therefore it is impossible to weigh separately the contributions of the observational and experimental approaches to the question of nerve fiber development. Both were necessary for the ultimate acceptance of the outgrowth theory. *** DIRECT SUPPORT *** A8402051 00004 相似文献
19.
Z. Bouček 《BioControl》1964,9(1):9-15
Summary The author reviews the European species of the Pteromalid genusCallitula
Spinola and keys them out. All four species develop as parasites, probably all on small Diptera: two species [pyrrhogaster (Walk.) andbicolor
spin.] on Cecidomyids and Chloropids in grass stems, two species are associated withPhragmites communis [C. ferrierei sp. n. andelongatus (Thoms)]. From the latter two one is described as new and in the other (elongatus) the so-far-unknown male is described. *** DIRECT SUPPORT *** A5180147 00002
相似文献
20.
Richard M. Straw 《Brittonia》1984,36(1):67-67
Penstemon apateticus Straw is found to be synonymous withP. miniatus Lindl.Penstemon miniatus subsp.apateticus andP. miniatus subsp.townsendianus are presented as new combinations. *** DIRECT SUPPORT *** A01CT127 00005 相似文献