The effect of temperature and photoperiod on the induction of embryonic diapause in the mosquito Aedes togoi (Theobald) (Diptera: Culicidae)

1987 ◽  
Vol 65 (9) ◽  
pp. 2266-2271 ◽  
Author(s):  
Brian E. Galka ◽  
Reinhart A. Brust
Keyword(s):  
Effect Of Temperature ◽  
Embryonic Diapause ◽  
Critical Photoperiod ◽  
Aedes Togoi

Aedes togoi (Theobald) from Vancouver, B.C., enters embryonic diapause when immatures, adults, and eggs are maintained at temperatures ranging from 22 to 28 °C, at photoperiods shorter than 15 h light/day. There was little to no embryonic diapause when the population was maintained at 24 °C and 17L:7D. The critical photoperiod was 14.4L:9.6D at 22 °C. A decrease in the frequency of diapause was observed as (i) temperature of the pupae, adults, and eggs increased from 18 to 28 °C when larvae were maintained at 24 °C 17L:7D; (ii) temperature of the egg stage increased from 15 to 30 °C, at 10L:14D, and stages preceding the egg stage were maintained at 24 °C 17L:7D; (iii) stages preceding the egg stage were maintained at 24 °C 17L:7D and the photoperiod was increased from 10L:14D to 18L:6D; (iv) temperature of the egg stage increased from 18 to 25 °C, at 10L:14D, and stages preceding the egg stage were maintained at 24 °C 17L:7D.

The effect of temperature and photoperiod on the induction of larval diapause in the mosquito Aedes togoi (Theobald) (Diptera: Culicidae)

1987 ◽  
Vol 65 (9) ◽  
pp. 2262-2265 ◽  
Author(s):  
Brian E. Galka ◽  
Reinhart A. Brust
Keyword(s):  
Larval Stage ◽  
Fourth Instar ◽  
Effect Of Temperature ◽  
Larval Diapause ◽  
Critical Photoperiod ◽  
Aedes Togoi

Aedes togoi (Theobald) from Vancouver, B.C., may enter diapause in either the egg or larval stage. Larval diapause occurred in the fourth instar, when immatures were maintained at 16 °C or less, at photoperiods shorter than 12 h light/day. The critical photoperiod was calculated as 10.9L:13.1D at 16 °C. Larvae that failed to pupate after 40 days following hatching were recorded as being in diapause. At light periods greater than 12 h at 16 °C, there was no larval diapause and, at 14 °C, 100% of the larvae diapaused at 10L:14D. Temperatures of 18 °C or higher, at 10L:14D, prevented larval diapause.

Geography of larval dormancy in the tree-hole mosquito, Aedes triseriatus (Say)

1981 ◽  
Vol 59 (6) ◽  
pp. 1014-1021 ◽  
Author(s):  
Christina M. Holzapfel ◽  
William E. Bradshaw
Keyword(s):  
Photoperiodic Response ◽  
Late Winter ◽  
Aedes Triseriatus ◽  
Embryonic Diapause ◽  
Rate Of Development ◽  
Larval Diapause ◽  
Tree Hole ◽  
Critical Photoperiod ◽  
Response To Temperature ◽  
Fail Safe

Among Aedes triseriatus from 30–40° N latitude, photoperiod and temperature mediate the onset and maintenance of larval diapause. Photoperiod has a significant effect not only on the initiation and maintenance of diapause but also on the rate of postdiapause development, both directly and by modifying response to temperature. The critical photoperiod for larval diapause is shorter than that for controlling rate of development. Over most of the range considered, both the critical photoperiod for the induction and maintenance of larval diapause and that for rate of development are shorter than the critical photoperiod governing embryonic diapause. Based on relative photoperiodic response and censuses of overwintering populations, we conclude that larval diapause in A. triseriatus is mainly a backup or fail-safe system for embryonic diapause and that the major adaptive significance of larval diapause relates to the modulation of late winter and spring development rather than to overwintering, per se.

Nucleation of Disorder in Fe3Al Alloys

1967 ◽  
Vol 25 ◽  
pp. 312-313
Author(s):  
P. R. Swann ◽  
W. R. Duff ◽  
R. M. Fisher
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Annealing Temperature ◽  
Antiphase Domain ◽  
Effect Of Temperature ◽  
Domain Structures ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Higher Temperature ◽  
The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

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 development of dormancy in bulblets of Lilium speciosum generated in vitro. II. The effect of temperature

1990 ◽  
Vol 80 (3) ◽  
pp. 431-436 ◽  
Author(s):  
Isabelle Delvallee ◽  
Annie Paffen ◽  
Geert-Jan De Klerk
Keyword(s):  
Effect Of Temperature ◽  
Lilium Speciosum

Effect of Temperature on ADP-Induced Platelet Aggregation

1973 ◽  
Vol 29 (01) ◽  
pp. 183-189
Author(s):  
C. A Praga ◽  
E. M Pogliani
Keyword(s):  
Platelet Aggregation ◽  
Incubation Period ◽  
Room Temperature ◽  
Important Variable ◽  
Practical Significance ◽  
Effect Of Temperature ◽  
Induce Platelet Aggregation ◽  
Cuvette Holder ◽  
Exact Temperature

SummaryTemperature represents a very important variable in ADP-induced platelet aggregation.When low doses of ADP ( < 1 (μM) are used to induce platelet aggregation, the length of the incubation period of PRP in the cuvette holder of the aggregometer, thermostatted at 37° C, is very critical. Samples of the same PRP previously kept at room temperature, were incubated for increasing periods of time in the cuvette of the aggregometer before adding ADP, and a significant decrease of aggregation, proportional to the length of incubation, was observed. Stirring of the PRP during the incubation period made these changes more evident.To measure the exact temperature of the PRP during incubation in the aggre- gometer, a thermocouple device was used. While the temperature of the cuvette holder was stable at 37° C, the PRP temperature itself increased exponentially, taking about ten minutes from the beginning of the incubation to reach the value of 37° C. The above results have a practical significance in the reproducibility of the platelet aggregation test in vitro and acquire particular value when the effect of inhibitors of ADP induced platelet aggregation is studied.Experiments carried out with three anti-aggregating agents (acetyl salicyclic acid, dipyridamole and metergoline) have shown that the incubation conditions which influence both the effect of the drugs on platelets and the ADP breakdown in plasma must be strictly controlled.

Effect of Temperature, Velocity Gradient and I.V. Heparin on in Vitro Blood Coagulation and Platelet Aggregation

1967 ◽  
Vol 17 (01/02) ◽  
pp. 112-119 ◽  
Author(s):  
L Dintenfass ◽  
M. C Rozenberg
Keyword(s):  
Blood Coagulation ◽  
Velocity Gradient ◽  
Elevated Temperatures ◽  
Morphological Changes ◽  
Effect Of Temperature ◽  
Clotting Time ◽  
Progressive Change ◽  
Aggregation Of Platelets ◽  
Microscopic Techniques

SummaryA study of blood coagulation was carried out by observing changes in the blood viscosity of blood coagulating in the cone-in-cone viscometer. The clots were investigated by microscopic techniques.Immediately after blood is obtained by venepuncture, viscosity of blood remains constant for a certain “latent” period. The duration of this period depends not only on the intrinsic properties of the blood sample, but also on temperature and rate of shear used during blood storage. An increase of temperature decreases the clotting time ; also, an increase in the rate of shear decreases the clotting time.It is confirmed that morphological changes take place in blood coagula as a function of the velocity gradient at which such coagulation takes place. There is a progressive change from the red clot to white thrombus as the rates of shear increase. Aggregation of platelets increases as the rate of shear increases.This pattern is maintained with changes of temperature, although aggregation of platelets appears to be increased at elevated temperatures.Intravenously added heparin affects the clotting time and the aggregation of platelets in in vitro coagulation.

Modeling fine particles and alkali metal compound behavior in a kraft recovery boiler

TAPPI Journal ◽  
2012 ◽  
Vol 11 (7) ◽  
pp. 9-14 ◽  
Author(s):  
AINO LEPPÄNEN ◽  
ERKKI VÄLIMÄKI ◽  
ANTTI OKSANEN
Keyword(s):  
Alkali Metal ◽  
Computational Models ◽  
Fine Particles ◽  
Black Liquor ◽  
Melting Behavior ◽  
Metal Compound ◽  
Effect Of Temperature ◽  
Particle Model ◽  
Boiler Furnace ◽  
Recovery Boiler

Under certain conditions, ash in black liquor forms a locally corrosive environment in a kraft recovery boiler. The ash also might cause efficiency losses and even boiler shutdown because of plugging of the flue gas passages. The most troublesome compounds in a fuel such as black liquor are potassium and chlorine because they change the melting behavior of the ash. Fouling and corrosion of the kraft recovery boiler have been researched extensively, but few computational models have been developed to deal with the subject. This report describes a computational fluid dynamics-based method for modeling the reactions between alkali metal compounds and for the formation of fine fume particles in a kraft recovery boiler furnace. The modeling method is developed from ANSYS/FLUENT software and its Fine Particle Model extension. We used the method to examine gaseous alkali metal compound and fine fume particle distributions in a kraft recovery boiler furnace. The effect of temperature and the boiler design on these variables, for example, can be predicted with the model. We also present some preliminary results obtained with the model. When the model is developed further, it can be extended to the superheater area of the kraft recovery boiler. This will give new insight into the variables that increase or decrease fouling and corrosion

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