Caractéristiques biodémographiques d'un acarien oribate (Carabodes willmanni) des pelouses xérophiles

1990 ◽  
Vol 68 (10) ◽  
pp. 2221-2229 ◽  
Author(s):  
A. Bellido
Keyword(s):  
Strong Influence ◽  
Postembryonic Development ◽  
Egg Laying ◽  
Adult Survival ◽  
Immature Stages ◽  
Small Species ◽  
Natural Conditions ◽  
Experimental Conditions ◽  
Influence Of Temperature ◽  
Influence Of Temperature On

An analysis of biodemographic characteristics was undertaken under experimental conditions in Carabodes willmanni, the first study of its kind in the superfamily Carabodoidea. The species dominates the microarthropod fauna of dry Cladonia cover. Immature stages have a very soft integument and live within the decomposing lichen layer. The population is characterized by the following: (i) low fecundity, strongly density dependent; (ii) relatively long postembryonic development for such a small species, lasting 117 days at 20 °C; (iii) extended premoulting stage (pupation), lasting 28% of postembryonic development; (iv) high but very variable longevity, with values varying from 200 to 600 days between egg laying and death of the adult; (v) strong influence of temperature on fecundity, adult survival, and duration of embryonic and postembryonic developments: development is inhibited at 10 °C. Based on previously acquired information on the phenology of the population, a model for the life cycle under natural conditions is proposed. Periods favorable to development being greatly shortened by environmental factors, the duration of the cycle is lengthened and probably takes as much as 1 year under the harshest conditions. The success of C. willmanni in such an environment can be explained by the capacity of the immature stages to take advantage of the lichen substrate both as a source of food and as a means of protection against desiccation.[Journal translation]

scholarly journals The influence of temperature on the absorption of water by seeds of hordeum vulgare in relation to the temperature coefficient of chemical change

1912 ◽  
Vol 85 (582) ◽  
pp. 546-553 ◽  
Keyword(s):  
Hordeum Vulgare ◽  
Aqueous Solutions ◽  
Temperature Coefficient ◽  
Chemical Change ◽  
Experimental Conditions ◽  
Influence Of Temperature ◽  
Suitable Medium ◽  
Influence Of Temperature On

Attention has previously been directed by one of us to the existence of a differential septum enclosing the seeds of Hordeum (barley). When the seeds are immersed in aqueous solutions of most electrolytes, and of many non-electrolytes, this covering behaves as a very efficient differential septum, water alone entering the seeds under the attractive influence of the finely granulated contents. The rate at which the water enters is considerably affected if substances are dissolved in it, being increased by some and diminished by others; it is also markedly dependent on the temperature of the water or solution in which the seeds are immersed. Variations of the rate at which water enters with alterations of the experimental conditions are presumably due mainly to changes in the water, and the seeds of Hordeum would thus appear to be a very suitable medium for the investigation of the nature of the changes produced in water by the presence of dissolved substances or by alterations of temperature.

The influence of temperature on the succession of redial and cercarial generations of Fasciola gigantica in a snail host

Parasitology ◽  
1964 ◽  
Vol 54 (1) ◽  
pp. 59-65 ◽  
Author(s):  
J. A. Dinnik ◽  
N. N. Diknik
Keyword(s):  
Larval Development ◽  
Low Temperatures ◽  
First Generation ◽  
Cold Season ◽  
Snail Host ◽  
Fasciola Gigantica ◽  
Natural Conditions ◽  
Influence Of Temperature ◽  
Cercarial Production ◽  
Influence Of Temperature On

Experiments on the larval development of Fasciola gigantica carried out under natural conditions have shown that at temperatures of 16° C. or less the rediae did not produce cercariae. The first-generation rediae, developed from the sporocyst, and all the rediae of subsequent generations produced only daughter rediae and did not change over to the production of cercariae as long as the low temperatures of the cold season lasted.As soon as the cold season ended and the temperature of the water in the aquaria containing the infected snails rose to a mean maximum of 20° C. all the rediae switched from redial to cercarial production.

Effect of Temperature on the Predator, (Reuter) (Hemiptera: Anthocordiae) Feeding on Cryptolestes pusillus (Schon.) (Coleoptera: Cucujidae)

1970 ◽  
Vol 15 ◽  
pp. 41-46 ◽  
Author(s):  
MM Rahman ◽  
W Islam ◽  
KN Ahmed
Keyword(s):  
Life History ◽  
Insect Pest ◽  
Developmental Time ◽  
Effect Of Temperature ◽  
Hatching Rate ◽  
Immature Stages ◽  
Egg Hatching ◽  
Influence Of Temperature ◽  
Influence Of Temperature On ◽  
Cryptolestes Pusillus

Xylocoris flavipes (Reuter) is one of the dominant predators of many stored product insect pest including Cryptolestes pusillus. The influence of temperature on predator development, survival and some selected life history parameters was determined. Eggs laid/female (27.27±2.52) and egg hatching rate (%) (88.25±2.19) were highest at 30°C and lowest at 20°C (5.43±1.19 and 30.79±4.63%) respectively but no eggs laid at 15°C. Mortality among immature stages (%) was highest (51.71±1.48) at 35°C and lowest (24.25c±1.14) at 25°C. Developmental times decreasing with the increasing of temperature. Maximum numbers of progeny/female/day (3.55±0.76) were produced at 25°C and minimum (0.83±0.04) were at 20°C.The sex ratios (% female) of X. flavipes were 47.04, 56.68, 51.66 and 50.07 for 20, 25, 30 and 35°C respectively. Survivorship of ovipositing females was highest at 25°C but lowest at 35°C respectively. Key words: Xylocoris flavipes, Cryptolestes pusillus, life history, temperature, developmental time   doi: 10.3329/jbs.v15i0.2201 J. bio-sci. 15: 41-46, 2007

Temperature Coefficient of Vulcanization on a Litharge Compound

1929 ◽  
Vol 2 (4) ◽  
pp. 505-516
Author(s):  
J. R. Sheppard
Keyword(s):  
Temperature Coefficient ◽  
Experimental Conditions ◽  
Influence Of Temperature ◽  
Influence Of Temperature On ◽  
Exact Relationship

Abstract THE influence of temperature on vulcanization is too well known to require emphasis—it has been generally recognized for quite a number of years that the relation between temperature and time for ordinary curing ranges was logarithmic although there has been no unanimity as to the exact relationship. This doubtless is in part due to the varying experimental conditions employed by the investigators and possibly in some cases to less precise measurements. Table I, a partial bibliography, shows some values for the temperature coefficient which have been obtained and the conditions used. It will be seen that values ranging from 8 to 25 have been reported for the coefficient (in terms of degrees Fahrenheit required to double the rate of cure). It is the purpose of this paper to recount the writer's determination of the temperature coefficient for a given litharge stock in press cures—it is not safe perhaps to infer from the present results what might hold under certain other conditions.

Influence of temperature on the liquid-to-liquid extraction of ethanol from (water + ethanol + 1,2-dichloroethane)

1992 ◽  
Vol 70 (8) ◽  
pp. 2310-2313 ◽  
Author(s):  
Horacio N. Sólimo ◽  
José L. Zurita
Keyword(s):  
Experimental Data ◽  
Conjugate Points ◽  
Liquid Equilibrium ◽  
Experimental Conditions ◽  
Influence Of Temperature ◽  
Equilibrium Data ◽  
Tie Lines ◽  
Influence Of Temperature On ◽  
Tie Line ◽  
System Water

To evaluate the influence of temperature on the extraction of ethanol from aqueous solutions with 1,2-dichloroethane, liquid–liquid equilibrium data for the system water + ethanol + 1,2-dichloroethane were obtained at 298.15, 308.15, and 318.15 K. The binodal curves were determined by the cloud-point method, and conjugate points on the tie-lines were obtained by correlating the refractive index of these curves as a function of composition. The tie-line data at each temperature were satisfactorily correlated using the method of Othmer and Tobias, and the plait-point coordinates were estimated. The experimental data were also compared to values calculated by the UNIFAC group contribution method for the activity coefficients using the isoactivity conditions as restraint equations, and with the NRTL and UNIQUAC models. The UNIFAC method proved to be more accurate than the NRTL and UNIQUAC equations fitted to the experimental data. Under the experimental conditions used, ethanol extraction by 1,2-dichloroethane appears to be independent of the temperature.

The effect of temperature on high-resolution TEM image contrast

1995 ◽  
Vol 53 ◽  
pp. 640-641
Author(s):  
T. Geipel ◽  
W. Mader ◽  
P. Pirouz
Keyword(s):  
Form Factor ◽  
Inelastic Scattering ◽  
Accurate Method ◽  
Waller Factor ◽  
Effect Of Temperature ◽  
Specimen Thickness ◽  
Influence Of Temperature ◽  
Debye Waller Factor ◽  
Influence Of Temperature On ◽  
Atomic Form Factor

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).

The Influence of Temperature on Successful Reproductions of Burbot, Lota Lota (L.) Under Hatchery Conditions

2010 ◽  
Vol 25 (1) ◽  
pp. 93-105 ◽  
Author(s):  
Daniel Żarski ◽  
Dariusz Kucharczyk ◽  
Wojciech Sasinowski ◽  
Katarzyna Targońska ◽  
Andrzej Mamcarz
Keyword(s):  
Lota Lota ◽  
Influence Of Temperature ◽  
Influence Of Temperature On
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