scholarly journals Ingestion and growth rates of Aurelia coerulea polyps fed naturally occurring copepods as food

2021 ◽  
Vol 38 (2) ◽  
pp. 15-19
Author(s):  
Haruto Ishii ◽  
Yoko Takahashi
Keyword(s):  
Growth Rates ◽  
Aurelia Coerulea ◽  
Naturally Occurring

scholarly journals Some observations on the influence of the micro-environment on loss of M substance in strains of Streptococcus pyogenes

1956 ◽  
Vol 54 (1) ◽  
pp. 89-98
Author(s):  
P. J. Wormald
Keyword(s):  
Streptococcus Pyogenes ◽  
Growth Rates ◽  
Liquid Media ◽  
Naturally Occurring ◽  
Nutrient Value ◽  
Type 3 ◽  
Selection Of ◽  
Apparently Healthy

1. An M-producing strain of Streptococcus pyogenes type-12 was shown to be carried on the surface of apparently healthy tonsils for at least 3 years.2. Loss of M substance in a strain of type-3 in a tonsillar carrier was shown to be by gradual replacement of matt forms by glossy variants. This pair of naturally occurring variants showed very different growth rates as mixtures in liquid media.3. Under suitable conditions, glossy variants regularly appeared and replaced the M-producing strain from which they were derived in these and all other strains of type-3 and type-12 tested from a wide variety of sources.4. It is suggested that the selection of variants by the differential nutrient value of the micro-environment is the deciding factor in carrier strains showing loss of M substance.

scholarly journals Virus transcript levels and cell growth rates after naturally occurring HPV16 integration events in basal cervical keratinocytes

2014 ◽  
Vol 233 (3) ◽  
pp. 281-293 ◽  
Author(s):  
Cinzia G Scarpini ◽  
Ian J Groves ◽  
Mark R Pett ◽  
Dawn Ward ◽  
Nicholas Coleman
Keyword(s):  
Cell Growth ◽  
Growth Rates ◽  
Transcript Levels ◽  
Naturally Occurring

scholarly journals Impact of the groundnut leafminer, Aproaerema modicella (Deventer) (Lepidoptera: Gelechiidae) on growth and yield of two groundnut cultivars

1995 ◽  
Vol 16 (1) ◽  
pp. 87-91
Author(s):  
T.G. Shanower ◽  
A.P. Gutierrez ◽  
J.A. Wightman
Keyword(s):  
Growth Rates ◽  
Untreated Control ◽  
Growth And Yield ◽  
Plant Mortality ◽  
Aproaerema Modicella ◽  
Naturally Occurring ◽  
Leaf Mining ◽  
Growth Development ◽  
The Impact ◽  
Stem Production

AbstractThe impact of larval defoliation by Aproaerema modicella (Deventer) on the growth, development and yield of two groundnut cultivars (Kadiri 3 and NC Ac 17090) was studied under a naturally occurring, high density infestation. Defoliation by leaf-mining larvae did not increase plant mortality in either cultivar. In both cultivars, leaf and stem production were significantly lower in untreated plots than in the treated plots. Unsprayed plants of both cultivars produced fewer flowers, pegs, and pods per plant compared to plants of the same cultivar protected with monocrotophos. Fruit growth rates, however, were marginally higher in control plots than in treated plots. Pod yields were 35 and 44% lower, and haulm yields 25 and 20% lower, in Kadiri 3 and NC Ac 17090, respectively in untreated control plots compared to plots treated with insecticide. A linear relationship between leafminer density and pod and haulm yields was observed, and differences between cultivars were not significant.

The Importance of Comparative Growth Rates in Determining the Canopy Composition of Tasmanian Rainforest

1995 ◽  
Vol 43 (3) ◽  
pp. 243 ◽  
Author(s):  
J Read
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
High Growth ◽  
Forest Stands ◽  
Lower Growth ◽  
Naturally Occurring ◽  
Significant Difference ◽  
Pot Trials ◽  
Canopy Composition ◽  
Study Sites

Growth rates of the rainforest canopy species Atherosperma moschatum Labill., Eucryphia lucida (Labill.) Baill., Nothofagus cunninghamii (Hook.) Oerst., Athrotaxis selaginoides D.Don and Phyllocladus aspleniifolius (Labill.) Hook.f. were measured in naturally-occurring seedlings and in seedlings grown in glasshouse pot trials. The highest field growth rates were recorded in N. cunninghamii on lowland sites on fertile, well-drained soils. On poorer soils, growth rates of N. cunninghamii were lower and there was little difference in growth rates between species. On the most acidic and probably infertile soil, the growth rate of P. aspleniifolius was 1.4 times higher than that of N. cunninghamii, although not significantly different at the 95% level. Similar trends in growth rates were recorded in pot trials. High growth rates were recorded in N. cunninghamii and E. lucida on fertile, well-drained soils, with generally lower growth rates in A. moschatum, P. aspleniifolius and A. selaginoides. No significant difference in growth rate was recorded among N. cunninghamii, E. lucida, A. moschatum and P. aspleniifolius when grown in poor soils or in low nutrient treatments. The trends in comparative growth rates correlate with the measured canopy composition of the study sites. Nothofagus cunninghamii dominates forest stands on sites where it has a clearly superior growth rate compared with co-occurring light-demanding species. Mixed canopies occur on sites where there is little or no difference between species' growth rates. However, not all patterns of canopy dominance can be explained by comparative growth rates alone. For example, P. aspleniifolius commonly dominates forest stands at low to mid-altitude where growth rates of all species are very low, but without necessarily a higher growth rate in P. aspleniifolius than in co-occurring species. The results of the growth rate studies are integrated with some other aspects of the biology of these species in a discussion of the mechanisms determining canopy composition of Tasmanian rainforests.

Variation in growth rates and aggressiveness of naturally occurring self-fertile and self-sterile isolates of the wilt pathogenCeratocystis albifundus

2015 ◽  
Vol 64 (5) ◽  
pp. 1103-1109 ◽  
Author(s):  
D. H. Lee ◽  
J. Roux ◽  
B. D. Wingfield ◽  
M. J. Wingfield
Keyword(s):  
Growth Rates ◽  
Naturally Occurring

Pathology of Bone Cells in Pigs with Experimental Turbinate Osteoporosis (Atrophic Rhinitis)

1971 ◽  
Vol 29 ◽  
pp. 304-305
Author(s):  
A. W. Fetter ◽  
C. C. Capen
Keyword(s):  
Mucous Membrane ◽  
Bone Cells ◽  
Atrophic Rhinitis ◽  
Infectious Agents ◽  
Metabolic Disturbances ◽  
Progressive Reduction ◽  
Naturally Occurring ◽  
Fundamental Cause ◽  
Osteocytic Osteolysis ◽  
Uncertain Etiology

Atrophic rhinitis in swine is a disease of uncertain etiology in which infectious agents, hereditary predisposition, and metabolic disturbances have been reported to be of primary etiologic importance. It shares many similarities, both clinically and pathologically, with ozena in man. The disease is characterized by deformity and reduction in volume of the nasal turbinates. The fundamental cause for the localized lesion of bone in the nasal turbinates has not been established. Reduced osteogenesis, increased resorption related to inflammation of the nasal mucous membrane, and excessive resorption due to osteocytic osteolysis stimulated by hyperparathyroidism have been suggested as possible pathogenetic mechanisms.The objectives of this investigation were to evaluate ultrastructurally bone cells in the nasal turbinates of pigs with experimentally induced atrophic rhinitis, and to compare these findings to those in control pigs of the same age and pigs with the naturally occurring disease, in order to define the fundamental lesion responsible for the progressive reduction in volume of the osseous core.

High Resolution Replication of Organoclay Surfaces

1982 ◽  
Vol 40 ◽  
pp. 576-577
Author(s):  
W. W. Barker ◽  
W. E. Rigsby ◽  
V. J. Hurst ◽  
W. J. Humphreys
Keyword(s):  
Clay Mineral ◽  
Organic Molecule ◽  
Organic Molecules ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
X Ray ◽  
Naturally Occurring ◽  
Silicate Layers ◽  
Mineral Identification

Experimental clay mineral-organic molecule complexes long have been known and some of them have been extensively studied by X-ray diffraction methods. The organic molecules are adsorbed onto the surfaces of the clay minerals, or intercalated between the silicate layers. Natural organo-clays also are widely recognized but generally have not been well characterized. Widely used techniques for clay mineral identification involve treatment of the sample with H2 O2 or other oxidant to destroy any associated organics. This generally simplifies and intensifies the XRD pattern of the clay residue, but helps little with the characterization of the original organoclay. Adequate techniques for the direct observation of synthetic and naturally occurring organoclays are yet to be developed.

SEM study of the morphological effects of kinetin and zeatin on the growth and development of the apical meristem in wheat

1995 ◽  
Vol 53 ◽  
pp. 978-979
Author(s):  
G. M. Hutchins ◽  
J. S. Gardner
Keyword(s):  
Growth And Development ◽  
Furfuryl Alcohol ◽  
Apical Meristem ◽  
Plant Cells ◽  
Triticum Aestivum L ◽  
Morphological Development ◽  
Naturally Occurring ◽  
Chinese Spring Wheat ◽  
Sem Study ◽  
Moist Environment

Cytokinins are plant hormones that play a large and incompletely understood role in the life-cycle of plants. The goal of this study was to determine what roles cytokinins play in the morphological development of wheat. To achieve any real success in altering the development and growth of wheat, the cytokinins must be applied directly to the apical meristem, or spike of the plant. It is in this region that the plant cells are actively undergoing mitosis. Kinetin and Zeatin were the two cytokinins chosen for this experiment. Kinetin is an artificial hormone that was originally extracted from old or heated DNA. Kinetin is easily made from the reaction of adenine and furfuryl alcohol. Zeatin is a naturally occurring hormone found in corn, wheat, and many other plants.Chinese Spring Wheat (Triticum aestivum L.) was used for this experiment. Prior to planting, the seeds were germinated in a moist environment for 72 hours.

Fine structure and properties of defects in naturally occurring silicates and oxides

1990 ◽  
Vol 48 (4) ◽  
pp. 460-461
Author(s):  
David R. Veblen
Keyword(s):  
Chemical Reactions ◽  
High Resolution Electron Microscopy ◽  
Extended Defects ◽  
Single Chain ◽  
Naturally Occurring ◽  
Resolution Electron ◽  
Fine Structures ◽  
Image Simulations ◽  
Similar Crystal Structure

Extended defects and interfaces control many processes in rock-forming minerals, from chemical reactions to rock deformation. In many cases, it is not the average structure of a defect or interface that is most important, but rather the structure of defect terminations or offsets in an interface. One of the major thrusts of high-resolution electron microscopy in the earth sciences has been to identify the role of defect fine structures in reactions and to determine the structures of such features. This paper will review studies using HREM and image simulations to determine the structures of defects in silicate and oxide minerals and present several examples of the role of defects in mineral chemical reactions. In some cases, the geological occurrence can be used to constrain the diffusional properties of defects.The simplest reactions in minerals involve exsolution (precipitation) of one mineral from another with a similar crystal structure, and pyroxenes (single-chain silicates) provide a good example. Although conventional TEM studies have led to a basic understanding of this sort of phase separation in pyroxenes via spinodal decomposition or nucleation and growth, HREM has provided a much more detailed appreciation of the processes involved.

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