Physical and Biological Factors Affecting the Longevity and Oviposition of Engorged Rhipicephalus sanguineus Female Ticks

1967 ◽  
Vol 53 (2) ◽  
pp. 432 ◽  
Author(s):  
Gordon K. Sweatman
Keyword(s):  
Rhipicephalus Sanguineus ◽  
Biological Factors ◽  
Factors Affecting

scholarly journals FAKTOR-FAKTOR YANG MEMPENGARUHI TOKSISITAS BAHAN PENCEMAR TERHADAP ORGANISME PERAIRAN

OSEANA ◽  
2019 ◽  
Vol 42 (2) ◽  
pp. 12-22
Author(s):  
Triyoni Purbonegoro
Keyword(s):  
Environmental Factors ◽  
Physicochemical Properties ◽  
Aquatic Environment ◽  
Aquatic Ecosystems ◽  
Physiological Condition ◽  
Aquatic Organisms ◽  
Combined Effects ◽  
Biological Factors ◽  
Factors Affecting ◽  
Major Factors

FACTORS THAT AFFECTING THE TOXICITY OF POLLUTANTS TO AQUATIC ORGANISMS. There are a large number of pollutants in aquatic environment with various characteristics and factors that can modify and affect the toxicity of pollutants in this environment. The major factors affecting pollutant toxicity include physicochemical properties of pollutants, mode of exposure, time, environmental factors, and biological factors. Moreover, organisms in an aquatic ecosystem are seldom exposed to only single pollutant, and most cases the stress of pollution on aquatic ecosystems is related to the interaction and combined effects of many chemicals. The combined effects may be synergistic or antagonistic, depending on the pollutants and the physiological condition of the organism involved.

Biological factors affecting enflagellation of Naegleria fowleri

1982 ◽  
Vol 152 (2) ◽  
pp. 803-808
Author(s):  
T W Woodworth ◽  
D T John ◽  
S G Bradley
Keyword(s):  
Population Density ◽  
Stationary Phase ◽  
Culture Medium ◽  
Actinomycin D ◽  
Suitable Model ◽  
Naegleria Fowleri ◽  
Biological Factors ◽  
Factors Affecting ◽  
Nægleria Fowleri ◽  
Amoeboid Cells

Naegleria fowleri is a pathogenic amoeboflagellate that can be evoked to transform from amoebae to flagellates by subculture to nonnutrient buffer. More than half of the amoebae of strains KUL, nN68, and Lovell became enflagellated 300 min after subculture to amoeba-saline, whereas no amoebae of strains NF66, NF69, and HB4 did. N. fowleri nN68 enflagellated best when grown at 32 or 37 degrees C and subcultured to amoeba-saline at 37 or 42 degrees C. Amoebae from the stationary phase of growth enflagellated more readily than did actively growing amoebae. Incubation in expended culture medium from stationary-phase cultures enhanced the capability of growing amoebae to enflagellate after subculture to amoebasaline. Enflagellation was more extensive when the population density in amoebasaline did not exceed 2 x 10(5) amoebae per ml. Cycloheximide at 1 microgram/ml and actinomycin D at 25 micrograms/ml inhibited growth of N. fowleri nN68. Cycloheximide at 0.5 microgram/ml and actinomycin D at 25 micrograms/ml completely prevented enflagellation when added at time zero. Cycloheximide at 0.5 microgram/ml, added 120 to 300 min after initiation of enflagellation, prevented further differentiation and caused existing flagellates to revert to amoeboid cells. Similarly, actinomycin D at 25 micrograms/ml, added 90 to 300 min after initiation of enflagellation, retarded differentiation and caused flagellates to revert. Radiolabeled precursors were incorporated into macromolecules during differentiation in nonnutrient buffer. Enflagellation of N. fowleri is a suitable model for studying regulation of a eucaryotic protist.

scholarly journals Biological factors affecting long-term results of valvular heterografts

1969 ◽  
Vol 58 (4) ◽  
pp. 467-483 ◽  
Author(s):  
Alain Carpentier ◽  
Guy Lemaigre ◽  
Ladislas Robert ◽  
Sophie Carpentier ◽  
Charles Dubost ◽  
...  
Keyword(s):  
Long Term Results ◽  
Biological Factors ◽  
Factors Affecting

Chemical and biological factors affecting mutagen potency

1998 ◽  
Vol 400 (1-2) ◽  
pp. 479-492 ◽  
Author(s):  
Michael E. Colvin ◽  
Frederick T. Hatch ◽  
James S. Felton
Keyword(s):  
Biological Factors ◽  
Factors Affecting

Factors Affecting Parasitization of Spodoptera exigua (Lepidoptera: Noctuidae) and Sex Ratio of the Parasitoid Cotesia marginiventris (Hymenoptera: Braconidae)

2001 ◽  
Vol 36 (2) ◽  
pp. 188-198 ◽  
Author(s):  
P. Glynn Tillman
Keyword(s):  
Sex Ratio ◽  
Adult Female ◽  
Spodoptera Exigua ◽  
Beet Armyworm ◽  
Cotesia Marginiventris ◽  
Biological Factors ◽  
Female Progeny ◽  
Factors Affecting ◽  
Lepidoptera Noctuidae

Biological factors hypothesized to affect parasitization by Cotesia marginiventris (Cresson) (Hymenoptera: Braconidae), an endoparasitoid of larvae of the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), as well as its sex ratio, were examined in the laboratory. Highest parasitization occurred when (1) adult female parasitoids were closely associated with hosts, (2) adult female parasitoids were 1 day old, (3) a host:female parasitoid ratio of between 10:1 and 30:1 was maintained, (4) second-instar beet armyworms were used as hosts, and (5) adult female parasitoids were exposed to hosts for 24 h. Percentage of female progeny was higher when females were closely associated with second instars.

Physicochemical and biological factors affecting atmospheric methane oxidation in gray forest soils

Microbiology ◽  
2005 ◽  
Vol 74 (2) ◽  
pp. 216-220 ◽  
Author(s):  
I. K. Kravchenko ◽  
V. M. Semenov ◽  
T. V. Kuznetsova ◽  
S. A. Bykova ◽  
L. E. Dulov ◽  
...  
Keyword(s):  
Methane Oxidation ◽  
Forest Soils ◽  
Atmospheric Methane ◽  
Biological Factors ◽  
Factors Affecting ◽  
Gray Forest Soils

The importance of biological factors affecting trace metal concentration as revealed from accumulation patterns in co-occurring terrestrial invertebrates

2004 ◽  
Vol 127 (3) ◽  
pp. 335-341 ◽  
Author(s):  
Frederik Hendrickx ◽  
Jean-Pierre Maelfait ◽  
Nicolas Bogaert ◽  
Catarina Tojal ◽  
Gijs Du Laing ◽  
...  
Keyword(s):  
Trace Metal ◽  
Metal Concentration ◽  
Trace Metal Concentration ◽  
Biological Factors ◽  
Factors Affecting ◽  
Terrestrial Invertebrates
Sign in / Sign up

Export Citation Format

Share Document