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474992. Thermal independence of energy management in a tailed amphibian
- Creator:
- Baškiera, Senka and Gvoždík, Lumír
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- daily energy expenditure, energy allocation, locomotor activity, newt, and standard metabolic rate
- Language:
- English
- Description:
- The relationship between the minimum metabolic requirements (standard metabolic rate, SMR) and energy costs of non-mandatory physiological functions and behaviour is fundamental for understanding species responses to changing environmental conditions. Theory predicts that ectotherms manage their energy budget depending on whether the relationship between SMR and energy available for other tasks is negative (allocation model), neutral (independent model), or positive (performance model). Energy management has received more attention in endotherms than in ectotherms, where metabolic-behavioural relations may be affected by body temperature variation. We examined the predictions of energy management models at four body temperatures in alpine newts, Ichthyosaura alpestris, under laboratory conditions. High SMR reduced the amount of energy dedicated to food digestion and locomotor activity. The maximum metabolic rate for food digestion was positively related to SMR, while its relationship with locomotor activity was inconclusive. Body temperature affected the intercept but not the slope of these relationships. We conclude that (i) newts manage their energy budget according to the allocation model, (ii) energy management is insensitive to body temperature variation, and (iii) determining energy management models using indirect estimates may be misleading. These findings improve our understanding of the eco-evolutionary significance of SMR variation in tailed amphibians and other ectotherms.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474993. Thermal requirements for development and resource partitioning in aphidophagous guilds
- Creator:
- Dixon, Anthony F.G., Jarošík, Vojtěch , and Honěk , Alois
- Type:
- article, model:article, and TEXT
- Subject:
- Coccinellidae, Syrphidae, aphidophagous guilds, coexistence, intraguild predation, lower developmental threshold, phylogenetic constraint, cereals, and sycamore
- Language:
- English
- Description:
- The duration of the increase, peak and decline in abundance of the immature stages of sycamore and cereal aphids each year is ephemeral. These temporary resources are exploited by a sequence of aphidophagous insect predators. The temporal sequence in the appearance of the immature stages of coccinellids and syrphids in the sycamore and cereal aphid systems is defined. In spring in the sycamore aphid system and early summer in the cereal aphid system the immature stages of syrphids consistently appeared before those of coccinellids. In the case of the sycamore aphid the autumnal peak in abundance was on average larger than the spring peak, and although attacked by more syrphids, it was not exploited by coccinellids. These temporal patterns in the attack sequence are associated with a difference in the lower developmental thresholds (LDT) of these two groups of predators. The LDT of syrphids (4°C) enables them to be active at lower temperatures and to develop faster between 10° and 27°C than coccinellids, whose LDT is 10°C. As a consequence, early in the year, when temperatures are low but increasing, syrphids appear before and complete their development more quickly than coccinellids, and in the latter half of the year, when temperatures are generally lower and decreasing, only syrphids are likely to be able to complete their development before the aphids disappear. Thus, the niche shift between syrphids and coccinellids is possibly more a consequence of a phylogenetic constraint than a response to competition and or intraguild predation. The relevance of these findings for the ecology of intraguild predation is discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474994. Thermal requirements of Trissolcus grandis (Hymenoptera: Scelionidae), an egg parasitoid of sunn pest
- Creator:
- Iranipour, Shahzad, Nozad Bonab , Zahra, and Michaud, John P.
- Type:
- article, model:article, and TEXT
- Subject:
- Hymenoptera: Scelionidae, Trissolcus grandis, egg prasitoid, Hemiptera, Scutelleridae, Eurygaster integriceps, degree-day, development, sunn pest, fecundity, longevity, thermal constant, and thermal treshold
- Language:
- English
- Description:
- Trissolcus grandis is an important egg parasitoid of sunn pest, Eurygaster integriceps Puton (Hemiptera: Scutelleridae), the most serious pest of wheat in Iran. The thermal requirements of two populations of T. grandis were studied at five constant temperatures ranging from 20-32°C. Thermal thresholds for development were calculated using linear regression and degree-day models were determined by fitting non-linear equations to the data. The lower threshold for development was estimated to be 12.5 and 12.1°C, respectively, for males and females of the Bonab population, compared to 14.4 and 14.5°C for those of the Qaramalek population. Complete development required 143.8 and 162.8 degree-days, respectively, for males and females of the Bonab population and 116.9 and 124.6 for those of the Qaramalek population. Thus, wasps from the warmer region (Qaramalek) developed faster than those from the cooler region (Bonab), but had a higher thermal threshold for initiating development. Bonab females attained their highest fecundity (117.7 ± 7.2) at the lowest temperature tested (20°C), whereas the fecundity of Qaramalek females was maximal (96.8 ± 11.5) at 26°C. Biological control programmes that seek to augment wasp populations in wheat fields early in the spring, when natural rates of sunn pest parasitism tend to be low, should consider wasp thermal requirements to ensure the selection and release of locally-adapted parasitoids.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474995. Thermal-Heilbad Teplitz-Schönau: (älterster Kurort Böhmens)
- Publisher:
- Verlag des Kurausschusses der Stadtgemeinde
- Format:
- print and 44 s. : il. ; 20 cm + 1 barev. mapa (27 x 33 cm)
- Type:
- text, government publication, informační publikace, průvodce, model:monograph, and TEXT
- Subject:
- lázně, Česko, lázně--Česko, lázeňská zařízení, lázeňská zařízení--Česko, lázeňská péče, lázeňská péče--Česko, lázeňství, lázeňství--Česko, Šanov (Teplice, Česko), 615.8, 711, 725, and 614.2
- Language:
- German
- Description:
- Obsahuje rejstříky
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474996. Thermo-mechanical properties of NiTi closed coil springs--force degradation and force regeneration over time, viscous properties
- Creator:
- Bezrouk, Aleš, Balský, Libor, Smutný, Martin, Nosek, Tomáš, Záhora, Jiří, Hanuš, Josef, and Polma, Richard
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, časopisecké články, práce podpořená grantem, and TEXT
- Subject:
- pevnost v tlaku, elasticita, lidé, testování materiálů, nikl, ortodontické aparáty, pevnost v tahu, časové faktory, titan, and viskozita
- Language:
- English
- Description:
- INTRODUCTION: The aim of this study was to find out the impact of degradation and regeneration of force over time at NiTi springs on the value and course of the final acting force and to verify the possibility of using these phenomena for a directed transition to the reverse plateau and its maintaining. METHODS: Static and cyclic mechanical loadings were performed. At first unused springs were tested. Afterwards the springs were mechanically stabilized by stress cycling and finally tested again. The difference in shape of the working curves was assessed. For simulation and description of the force degradation the modified Voight model was used. RESULTS: New springs, mainly those with large hysteresis, showed a significant stress-strain curve movement and shape changes during the cycling. The effect of the stress-strain curve course change disappeared fully in the stabilized springs. Multiple loading led to an overall decrease of force value during the measurement. The effect of force degradation and regeneration over time by simple static loading varies in the range of percentage of the nominal force in the plateau area. The transition between stress-strain curve phases caused by the degradation or regeneration of the force wasn't observed in case of mechanically stabilized springs. CONCLUSIONS: Springs should be mechanically stabilized before their application. The degree of force degradation over time is insignificant for mechanically stabilized springs. Degradation or regeneration of force over time, mechanical stabilization or micromovements in the mouth don't cause any transition between individual stress-strain curve phases. and A. Bezrouk, L. Balský, M. Smutný, T. Nosek, J. Záhora, J. Hanus, R. Polma
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474997. Thermodynamic behaviour and the breakthrough capacity on the removal of brilliant green from aqueous solution by peels of prunus amygdalus: characterization and kinetic study :
- Creator:
- Usmani, S. Q.
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474998. Thermoperiodic effects on diapause of Sesamia nonagrioides (Lepidoptera: Noctuidae)
- Creator:
- Fantinou, Argyro A., Chatzoglou , Costas S., and Kagkou , Elena A.
- Type:
- article, model:article, and TEXT
- Subject:
- Sesamia nonagrioides, diapause induction, development, thermoperiod, and thermophotoperiod
- Language:
- English
- Description:
- The role of the thermophotoperiod on larval diapause induction and development of Sesamia nonagrioides was investigated under laboratory conditions. The incidences of diapause by TC 12 : 12 thermoperiods under DD, in which the thermophase was 30°C and cryophases varied from 10 to 25°C, were compared to the effects of thermophotoperiods with the same configuration. Higher incidences of diapause were recorded when larvae were exposed to thermophotoperiods with cryophases of 15-25°C, than under thermoperiods under constant darkness. In addition, larvae exhibited significantly lower percentages of diapause when exposed to cryophases < 15°C under either thermo- or thermophotoperiodic condition. Diapausing larvae when exposed to photoperiods 16L : 8D h and different temperatures of 25-30°C proceeded to development in 14-16 days. Moreover time needed for the pupation of diapausing larvae after their transfer to 12L : 12D h, was reduced from approximately 49 to 12 days depending on temperatures of exposures (25-30°C). Diapause termination was also compared under 12L : 12D h and constant temperature of 25°C or a thermoperiod of TC 12:12 (30°: 20°). Days needed for pupation at constant temperature or under the mentioned thermoperiodic regime, were approximately the same when the high temperature of the thermoperiod coincided with the scotophase, while with the co-occurrence of the high temperature of the thermoperiod and the photophase significantly additional time was needed for diapause development. Significantly shorter time was also needed for diapause development after exposure of diapausing larvae to continuous light, than to continuous darkness under 25°C. Thermoperiods of different amplitudes with the same mean temperatures proved that the higher temperature of scotophase led to higher rate of diapause development in spite of the relatively low temperature of the photophase tested. It is suggested that thermoperiod could hasten the time needed for diapause development, but it is not the crucial factor for the termination of diapause.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474999. Thermoregulation and the influence of body temperature on calling song parameters in Cicada orni (Hemiptera: Cicadidae)
- Creator:
- Sanborn, Allen F., Simões, Paula C., Phillips, Polly K., and Quartau, José A.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, bioacoustics, calling song, Cicada, Cicadidae, temperature, thermoregulation, 2, and 59
- Language:
- English
- Description:
- Measurements of body temperature in the field demonstrate that Cicada orni Linnaeus regulates body temperature through behavioral mechanisms. Behavior is used to regulate body temperature to a range necessary for calling. As predicted, results showed a general decrease of echeme duration and an increase in inter-echeme interval with rising body temperature. However, no statistically significant correlations of body temperature for any of the variables studied were found, giving evidence that there is more variability in call parameters between individuals than any effect of body temperature. and Allen F. Sanborn, Paula C. Simões, Polly K. Phillips, José A. Quartau.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
475000. Thersites vychovatelem
- Creator:
- Konrád, Edmond
- Format:
- electronic
- Type:
- model:article and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public