Temperature-induced pupil movements in insect superposition eyes

2000 ◽  
Vol 203 (4) ◽  
pp. 685-692 ◽  
Author(s):  
P. Nordstrom ◽  
E.J. Warrant
Keyword(s):  
High Temperatures ◽  
Cydia Pomonella ◽  
Codling Moth ◽  
Light Level ◽  
Agrotis Segetum ◽  
Effect Of Temperature ◽  
Activation Temperature ◽  
Ambient Light Level ◽  
Wide Range ◽  
Response To Temperature

In this paper, we describe the hitherto largely overlooked effect of temperature on the pupil of insect compound eyes. In the turnip moth Agrotis segetum and in two other nocturnal insects with superposition eyes, the lacewing Euroleon nostras and the codling moth Cydia pomonella, the pupil not only opens and closes with changes in the ambient light level, as expected, but also with changes in temperature in the absence of light. In complete darkness, the pupil of A. segetum responds over a wide range of temperatures, with the pupillary pigments migrating to a light-adapted position when the animal is exposed to either low or high temperatures. At temperatures between 21.0 and 22.7 C, the pigments migrate to the fully dark-adapted position, resulting in an open pupil and maximal eye glow. Pupil closure at high temperatures shows two distinct thresholds: the first at 23.8+/−0.7 C and a second some degrees higher at 25.7+/−1.2 C (means +/− s.d., N=10). Temperatures exceeding the first threshold (the activation temperature, T(a)) initiate a closure of the pupil that is completed when the temperature exceeds the second threshold (the closure temperature, T(c)), which causes rapid and complete migration of pigment to the light-adapted position. All temperatures above T(a) affect the pupil, but only temperatures exceeding T(c) result in complete closure. Temperatures between T(a) and T(c) cause a slow, partial and rather unpredictable closure. The lacewing and the codling moth both show very similar responses to those of A. segetum, suggesting that this response to temperature is widespread in superposition eyes. The possibility that the ambient temperature could be used to pre-adapt the eye to different light intensities is discussed.

Effects of juvenile hormone mimics on the codling moth Cydia Pomonella (L.) (Lep., Olethreutidae)

1973 ◽  
Vol 63 (1) ◽  
pp. 7-16 ◽  
Author(s):  
I. Gelbič ◽  
F. Sehnal
Keyword(s):  
Juvenile Hormone ◽  
Laboratory Experiments ◽  
Cydia Pomonella ◽  
Codling Moth ◽  
The Other ◽  
Wide Range ◽  
Juvenile Hormone Analogues ◽  
Juvenile Hormone Mimics

AbstractLaboratory experiments with juvenile hormone analogues on Cydia pomonella (L.) showed that Cecropia C17 juvenile hormone (methyl 10,ll-epoxy-3,7,ll-trimethyl-2,6-dodecadienoate) was the most active of the 28 compounds tested. When applied to four-hour-old eggs at 0.1 μg/egg, the hormone caused 100% failure in embryogenesis, while the other compounds were at least five times less effective. Depending on the time since ecdysis and the dose, juvenile hormone mimics applied to last-instar larvae resulted in a wide range of intermediate forms. Against three-day-old last-instar larvae, the Cecropia C17 hormone gave 100% inhibition of development at a dose of 1 μg/larva, while three other compounds (methyl 10,11-epoxy-3,7,11-trimethyl-2,6-dodecadienoate, ethyl 11-chloro-3,7,11-trimethyl-2-dodecenoate and ethyl 3,7,11-tri-methyl-2,4-dodecadienoate) gave the same effect at 2–5 μg/larva. Against newly emerged adults, the last two compounds at 10–50 μg/insect reduced fecundity and fertility to 0–81% and 0–50%, respectively, of their normal levels.

Effect of Temperature in Superplastic Forming in Al6063/SiCp Composites

2012 ◽  
Vol 538-541 ◽  
pp. 1111-1114 ◽  
Author(s):  
S. Vijay Ananth ◽  
M Kumerasan ◽  
K Kalaichelvan
Keyword(s):  
Liquid Phase ◽  
High Temperatures ◽  
Superplastic Forming ◽  
High Strength ◽  
Grain Boundary Sliding ◽  
Effect Of Temperature ◽  
Dome Height ◽  
High Ductility ◽  
Wide Range ◽  
Boundary Sliding

Superplastic forming in Al6063/SiCp composites having a wide range of applications in aerospace and automobile industries due to the high strength and wear resistance[7]. High percentage of elongation was obtained only at high temperatures. At high temperatures liquid phase will form in the grain boundaries. Due to the liquid phase, grain boundary sliding was easy to get the Newtonian viscous flow[1]. In composites high ductility was obtained only the temperature more than 560°C. The maximum dome height of 19 mm was obtained at 580°C. Temperature is more than 600°C the material was failed, fracture was occurred.

scholarly journals Visual Comfort of Tablet Devices under a Wide Range of Ambient Light Levels

2021 ◽  
Vol 11 (18) ◽  
pp. 8679
Author(s):  
Hsin-Pou Huang ◽  
Minchen Wei ◽  
Hung-Chung Li ◽  
Li-Chen Ou
Keyword(s):  
Evaluation Model ◽  
Light Level ◽  
White Background ◽  
Psychophysical Experiment ◽  
Visual Comfort ◽  
Ambient Light ◽  
Viewing Condition ◽  
Light Levels ◽  
Ambient Light Level ◽  
Wide Range

E-reading devices are becoming more and more common in our daily life, and they are used under a wide range of ambient light levels, from completely dark to extremely bright conditions. In this study, a psychophysical experiment is carried out to investigate how ambient light level affects the visual comfort of an e-reading device. Human observers compare the visual comfort of pairs of different text-background lightness combinations on a tablet device under three ambient light levels (i.e., 150, 1500, and 15,000 lx). With our previous work, the experimental results show that the trend of visual comfort interval scales below 1500 lx (i.e., Dark, 150, 300, and 1500 lx) are similar to each other but not for those under illuminance above the 1500 lx (i.e., 3000 and 15,000 lx). For the same lightness difference between text and background, the observers tend to read the text with a white background compared to a black background, especially for 3000 and 15,000 lx. Moreover, a black text on a light-gray background is the most comfortable combination under these two illuminance levels. An evaluation model is proposed based on ambient illuminance, screen parameters, and visual estimation to design an optimal viewing condition when reading on the tablet display.

scholarly journals Effect of temperature on flight initiation in Mastrus ridens

2014 ◽  
Vol 67 ◽  
pp. 325-325
Author(s):  
V.A. Davis ◽  
W.R.M Sandanayaka ◽  
A. Chhagan ◽  
J.G. Charles
Keyword(s):  
Cydia Pomonella ◽  
Codling Moth ◽  
Early Spring ◽  
Apple Orchard ◽  
Effect Of Temperature ◽  
Host Stage ◽  
Different Temperatures ◽  
Net Cage ◽  
Mastrus Ridens ◽  
Flight Initiation

Mastrus ridens (Horstmann) (Hymenoptera Ichneumonidae) is a gregarious ectoparasitoid of cocooned larvae of codling moth Cydia pomonella (L) (Lepidoptera Tortricidae) This host stage is available for parasitism by M ridens (which is not known to diapause) throughout winter and early spring A study was conducted at ambient field temperatures during this period to investigate the minimum temperature required for flight initiation by M ridens Ten female and 10 male adults (37 days old) from the laboratory were transferred into two containers and placed in an apple orchard for 1 h for temperatures to equilibrate The container was then opened inside a large net cage and the numbers of parasitoids that flew into the cage at different temperatures were recorded The experiment release periods while establishing the parasitoid throughout New Zealand and (2) determine when the females are first active in spring before the codling moth larvae pupate

The results of field trials of the codling moth pheromone preparations in 2020

2020 ◽  
Author(s):  
S.V. Dmitriyeva ◽  
◽  
I.M. Mityushev
Keyword(s):  
Russian Federation ◽  
Central Region ◽  
Cydia Pomonella ◽  
Codling Moth ◽  
Field Trials ◽  
Field Screening ◽  
Tube Type ◽  
The Russian Federation ◽  
Polyethylene Dispenser

This article presents the results of field screening of pheromone preparations of the codling moth, Cydia pomonella L., conducted in 2020 under conditions of the Central Region of the Russian Federation. The new «Tube» type dispensers were tested vs. standard foil-polyethylene dispenser.

scholarly journals Membrane Lipid Composition of the Moderately Thermophilic Ammonia-Oxidizing Archaeon “Candidatus Nitrosotenuis uzonensis” at Different Growth Temperatures

2019 ◽  
Vol 85 (20) ◽  
Author(s):  
Nicole J. Bale ◽  
Marton Palatinszky ◽  
W. Irene C. Rijpstra ◽  
Craig W. Herbold ◽  
Michael Wagner ◽  
...  
Keyword(s):  
Lipid Composition ◽  
Strong Influence ◽  
Thermal Spring ◽  
Membrane Lipid ◽  
Effect Of Temperature ◽  
Environmental Niche ◽  
Membrane Lipid Composition ◽  
Moderately Thermophilic ◽  
Wide Range ◽  
Membrane Spanning

ABSTRACT “Candidatus Nitrosotenuis uzonensis” is the only cultured moderately thermophilic member of the thaumarchaeotal order Nitrosopumilales (NP) that contains many mesophilic marine strains. We examined its membrane lipid composition at different growth temperatures (37°C, 46°C, and 50°C). Its lipids were all membrane-spanning glycerol dialkyl glycerol tetraethers (GDGTs), with 0 to 4 cyclopentane moieties. Crenarchaeol (cren), the characteristic thaumarchaeotal GDGT, and its isomer (crenʹ) were present in high abundance (30 to 70%). The GDGT polar headgroups were mono-, di-, and trihexoses and hexose/phosphohexose. The ratio of glycolipid to phospholipid GDGTs was highest in the cultures grown at 50°C. With increasing growth temperatures, the relative contributions of cren and crenʹ increased, while those of GDGT-0 to GDGT-4 (including isomers) decreased. TEX86 (tetraether index of tetraethers consisting of 86 carbons)-derived temperatures were much lower than the actual growth temperatures, further demonstrating that TEX86 does not accurately reflect the membrane lipid adaptation of thermophilic Thaumarchaeota. As the temperature increased, specific GDGTs changed relative to their isomers, possibly representing temperature adaption-induced changes in cyclopentane ring stereochemistry. Comparison of a wide range of thaumarchaeotal core lipid compositions revealed that the “Ca. Nitrosotenuis uzonensis” cultures clustered separately from other members of the NP order and the Nitrososphaerales (NS) order. While phylogeny generally seems to have a strong influence on GDGT distribution, our analysis of “Ca. Nitrosotenuis uzonensis” demonstrates that its terrestrial, higher-temperature niche has led to a lipid composition that clearly differentiates it from other NP members and that this difference is mostly driven by its high crenʹ content. IMPORTANCE For Thaumarchaeota, the ratio of their glycerol dialkyl glycerol tetraether (GDGT) lipids depends on growth temperature, a premise that forms the basis of the widely applied TEX86 paleotemperature proxy. A thorough understanding of which GDGTs are produced by which Thaumarchaeota and what the effect of temperature is on their GDGT composition is essential for constraining the TEX86 proxy. “Ca. Nitrosotenuis uzonensis” is a moderately thermophilic thaumarchaeote enriched from a thermal spring, setting it apart in its environmental niche from the other marine mesophilic members of its order. Indeed, we found that the GDGT composition of “Ca. Nitrosotenuis uzonensis” cultures was distinct from those of other members of its order and was more similar to those of other thermophilic, terrestrial Thaumarchaeota. This suggests that while phylogeny has a strong influence on GDGT distribution, the environmental niche that a thaumarchaeote inhabits also shapes its GDGT composition.

scholarly journals Effect of Temperature on the Development and Survival of Feltiella Acarisuga (Vallot) (Diptera: Cecidomyiidae) Preying on Tetranychus Urticae (Koch) (Acari: Tetranychidae)

Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 508
Author(s):  
Yong-Seok Choi ◽  
Sung-Hoon Baek ◽  
Min-Jung Kim
Keyword(s):  
Developmental Stages ◽  
Gall Midge ◽  
Mass Rearing ◽  
Immature Stage ◽  
Development Rate ◽  
Effect Of Temperature ◽  
Thermal Constant ◽  
Fundamental Information ◽  
Threshold Temperatures ◽  
Response To Temperature

The predatory gall midge, Feltiella acarisuga (Vallot) (Diptera: Cecidomyiidae), is an acarivorous species that mainly feeds on spider mites (Acarina: Tetranychidae). Because of its cosmopolitan distribution and predation efficacy, it is considered an important natural enemy available as a biological agent for augmentative biocontrol. However, despite its practical use, the thermal development and survival response to temperature have not yet been fully studied. In this study, we investigated the stage-specific development and survival of F. acarisuga at seven temperatures (11.5, 15.7, 19.8, 23.4, 27.7, 31.9, and 35.4 °C) to examine the effect of temperature on its lifecycle. All developmental stages could develop at 11.5–31.9 °C, but the performance was different according to the temperature. From the linear development rate models, the lower development threshold and thermal constant of the total immature stage were estimated at 8.2 °C and 200 DD, respectively. The potential optimal and upper threshold temperatures for the total immature stage were estimated as 29.3 and 35.1 °C using a non-linear development model. The operative thermal ranges for development and survival at 80% of the maximum rate were 24.5–32.3 and 14.7–28.7 °C, respectively. Thus, it was suggested that 24.5–28.7 °C was suitable for the total immature stage. In contrast, conditions around 8 °C and 35 °C should be avoided due to the lower development rate and high mortality. Our findings provide fundamental information for an effective mass-rearing and releasing program of F. acarisuga in an augmentative biocontrol program and help to predict phenology.

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