Differences In Temperature Responses Research Articles

P.1.116 Carbohydrate-rich diet in experimental models of depression

The hypercholinergic Flinders Sensitive Line (FSL) rat was significantly more sensitive than the Flinders Resistant Line (FRL) rat to the biotelemetrically recorded hypothermic effects of oxotremorine, a direct-acting muscarinic agonist, and diisopropyl fluorophosphate (DFP), an anticholinesterase agent. The effects of these agents on heart rate and motor activity, also recorded biotelemetrically, indicate either small differences (DFP) or no significant effect (oxotremorine) between the lines. These findings confirm the dramatic differences in temperature responses to cholinergic compounds between FSL and FRL rats, for which they were selectively bred, but suggest that a general increase in the sensitivity of the FSL rats to all muscarinic-mediated responses may not occur.

Temperature Response of Fragaria Species

Plants of a diverse collection of Fragaria clones from a range of native habitats representing F. chiloensis, F. virginiana, F. virginiana glauca, and F. vesca, were grown in a controlled environment at one of three day/night temperatures, 15/15, 23/15, or 31/15°C. Relative growth rate (RGR) and net assimilation rate (NAR) were estimated from plant leaf areas and total dry weights. At 23/15°C, the species mean RGR and NAR values were comparable although clones within species exhibited significant variation. At 15/15 and 31/15°C, RGR and NAR for species were lower than at 23/15°C. At 31/15°C, chiloensis and vesca mean values were reduced more than the others, to less than 50% the 23/15°C values. Also, NAR declined most for chiloensis, to 45% the 23/15°C value. At 15/15°C, virginiana had much higher RGR and NAR values than the other species, and its NAR mean value was greater than at 23/15°C. Although the species means would suggest that there are interspecific differences in temperature response, intraspecific variability was also large. Thus, classifying Fragaria species by temperature response may be an over-generalization.

Autonomic and behavioral responses of selectively bred hypercholinergic rats to oxotremorine and diisopropyl fluorophosphate

The hypercholinergic Flinders Sensitive Line (FSL) rat was significantly more sensitive than the Flinders Resistant Line (FRL) rat to the biotelemetrically recorded hypothermic effects of oxotremorine, a direct-acting muscarinic agonist, and diisopropyl fluorophosphate (DFP), an anticholinesterase agent. The effects of these agents on heart rate and motor activity, also recorded biotelemetrically, indicate either small differences (DFP) or no significant effect (oxotremorine) between the lines. These findings confirm the dramatic differences in temperature responses to cholinergic compounds between FSL and FRL rats, for which they were selectively bred, but suggest that a general increase in the sensitivity of the FSL rats to all muscarinic-mediated responses may not occur.

Oxygen evolution in clones of Ficus benjamina L. grown in different environmental conditions

Two clones of Ficus benjamina L. known to differ in growth rate were grown at 18, 20, 24 and 30°C and at PPFDs of 70, 140 and 200 μmol m −2 s −1. Light response curves were measured at growth temperature and at lower and higher temperature conditions in order to estimate differences in clonal responses. Values of maximum rate of photosynthesis (P max), apparent quantum yield (φ), saturating PPFD (I s) and apparent quantum efficiency were used to evaluate the state of the photosynthetic apparatus. No clonal differences were found, when plants were grown or measured at suboptimal temperatures (18°C), and only small differences were caused by different irradiances during growth. With higher cultivation temperature, clonal differences in P max became pronounced. Apparent quantum yield (φ) was lowest at 18°C, but increased with temperature. The results stress that observed differences in gas exchange after pretreatment form a complex pattern owing to basic differences in gas exchange and differences in temperature response. However genetic differences in photosynthesis were most clearly expressed in P max. This fact may be useful to include in greenhouse climate control models.

Rhodococcus equi foal pneumonia: protective effects of immune plasma in experimentally infected foals.

The immunoprophylactic capacity of specific immune plasma was evaluated in pony foals infected experimentally with Rhodococcus equi. Immune plasma, produced by repeated parenteral administration of viable R. equi to adult horses, was harvested and frozen. Group I (six control foals) and Group II (six principal foals) received lactated Ringers solution and immune plasma respectively at three and five days of age. R. equi were aerosolised into a caudal lung lobe of all foals at seven days of age. Clinical signs, haematological alterations, immune responses, thoracic radiographs and technetium99m pulmonary perfusion scans were monitored. All foals were destroyed and complete post mortem examinations performed. All foals developed pneumonia as evidenced by clinical, radiographic and perfusion alterations, but the survival rate of principal foals was significantly (P less than 0.01) greater than that of control foals. Five control foals developed terminal disease, whereas all principal foals recovered. There was no significant (P greater than 0.05) difference in temperature response, or peripheral blood leucocyte, neutrophil or fibrinogen concentrations between groups. ELISA values for R. equi antibody were significantly (P less than 0.001) greater in principal foals following treatment, but there was no significant (P greater than 0.05) difference in IgG or IgM concentrations between groups. Results of the haemolysis inhibition assay indicated that equi factor neutralising antibodies were transferred by immune plasma to the principal foals. Post mortem examinations of five control foals destroyed at approximately three weeks post infection because of terminal disease, revealed severe pyogranulomatous pneumonia. One control and all principal foals were either free of lesions or had resolving lesions and/or minimal scar formation at three months post infection.(ABSTRACT TRUNCATED AT 250 WORDS)

RAPS-a rapid thermal processor simulation program

Rapid thermal processors using incoherent light illumination have become an important semiconductor processing tool for implantation anneal, oxidation, and alloying. The application in ohmic contact alloying, however, has to be made very cautiously, for the thin metal layer drastically changes the optical characteristics and thus the thermal response of the contact region. A rapid thermal processor simulation (RAPS) program has been developed to study the difference in temperature response during rapid thermal annealing for various substrate materials and the effect of thin metal coating the substrates with films. The results are correlated with experimental observations. The results suggest that users of commercial rapid thermal processors should be cautious about the temperature-sensor setup, the application area, and the interpretation of the measured temperature. >

Uncoupling of Somatic and Otolith Growth Rates in Arctic Char (Salvelinus alpinus) as an Effect of Differences in Temperature Response

Experiments were conducted to study the effect of temperature, fish size, and somatic growth rate on mean daily otolith growth rate in Arctic char (Salvelinus alpinus) fry fed maximum rations. Long-term experiments at two different temperatures (8 and 13 °C) showed exponential relationships between otolith weight and fish wet weight, with the exponent of wet weight for the higher temperature being significantly higher than for the lower temperature. Increasing exponents at each sampling date indicated a difference in growth rates of the char and its otoliths. Short-term experiments showed that specific growth rate of the fry at six different temperatures was that of an optimum curve whereas the otolith growth rate continued to increase with increasing temperatures. A clear uncoupling between otolith growth rate and fish growth rate was demonstrated whereas temperature and fish wet weight modeled otolith growth rate reasonably well. It was found that otolith growth rate expressed as daily increase in weight gave a model with better fit and higher generality than growth rate along various radii. Several examples of uncoupling between fish growth rate and otolith growth rate in the literature were reexamined, and an explanation of otolith growth rate in terms of a metabolic expression was suggested.

キュウリ果実の生長に及ぼす果実温度の影響

The effect of fruit temperature on the growth of cucumber fruit at the early stage of development was investigated. Cucumber fruits attached on the vine were put in chambers controlled at temperatures ranging from 5° to 30°C.Relative growth rate (RGR) increased as the fruit temperature was raised to 30°C, and was estimated to be 0 at about 5°C. The multiple regressions of RGR on fruit temperature and fruit volume gave high multiple correlation coefficients for different seasons and cultivars. Partial correlation was positive between RGR and fruit temperature and negative between RGR and fruit volume. This indicated that the RGR of fruits at the same volume is almost linearly related to fruit temperature. However, an Arrhenius plot of RGR gave a line with a break point near 12°C, at which point a qualitative change in fruit growth was suggested to occur.Q10 of RGR was about 2 between 15° and 30°C regardless of the growing season, but for fruits at the same temperature, RGR was higher in spring than in winter. From this result it was suggested that a seasonal difference in RGR could be brought about by a difference in carbon concentration of phloem sap, while the influx rate of the phloem sap was determined by fruit temperature.There was no difference in temperature response of RGR between cultivars.

The genetic control of basic vegetative phase in early-maturing native rice varieties of Japan.

既報(佐藤・林 1985)で述べた感光相(PSP)が短かく基本栄養生長期間(BVP)も短かい早生品種群に属する日本の在来イネ品種について，到穂日数の温度反応(感温性)および基本栄養生長期間(BVP)の品種間差異とその遺伝様式を調べた.供試した早生24品種は，生育期間中の温度が高いほど到穂日数が減少し温度反応を示したが，その品種間差は小さかった.早生品種群内には到穂日数がさらに短かいもの，やや長いものの2群が存在した.BVPの長さを支配するEf-1b遺伝子との相同性検定の結果，多くの早生品種はEf-1b遺伝子とこの作用を強める複数の変更遺伝子をもつと推定されたが，一部の品種はEf-1b以外の早生遺伝子をもつと考えられた.Ef-1b遺伝子は，北海道から鹿児島に至る日本の各地に分布した.これらのことから北部日本の早生品種は必ずしもイネの北進の過程で自然淘汰の結果分化したとは限らず，むしろイネの日本への伝播の初期にすでに分化していた早生品種が選抜されて北上したと考えるほうがよいと結論された.

Temperature response of oxygen uptake in brain mitochondria from normal and ischemic rats

Mitochondria isolated from rat brains following 30 min of complete (decapitation) ischemia showed a 3-fold increase in free fatty acid content, but no significant decreases in the total fatty acid or phospholipid content. This free fatty acid increase was associated with an altered mitochondrial function: a 50% inhibition of state 3 (+ ADP) respiration and a decrease in the respiratory control ratio from 5.5 to 3 to 24°C. The P:O ratio remained unchanged at 3, and there was no increase in stage 4 respiration. When glutamate and malate supported respiration was determined as a function of temperature in control mitochondria, the resulting Arrhenius plot of the state 3 respiration was biphasic with a transition temperature around 30°C, while ischemic mitochondria exhibited a linear Arrhenius plot with energy of activation (approximately 10 kcal/mol) similar to that of control mitochondria below the transition temperature. The difference in temperature response between control and ischemic mitochondria reflects a change in mitochondrial lipid composition, and is therefore a functional manifestation of the altered cerebral lipid composition commonly observed during ischemia.

Wingstroke frequency of dragonflies (Odonata: Anisoptera) in relation of temperature and body size

1. Wingstroke frequency during pre-flight warm-up, fixed flight, and self-supported flight on a tether was measured at several body temperatures (Tb) in anisopterous dragonflies. 2. Frequency increases as body size (mass or wing length) decreases and asTb increases. The change in frequency for a given change in size is greater during flight than warm-up at any givenTb, while the rate of increase with temperature is greater during warm-up, regardless of size. 3. The relationship of frequency during flight to wing length departs significantly from that predicted by the harmonic oscillator model of Greenewalt (1960), but the discrepancy can be explained in part by the absence of geometric similarity among dragonflies. Scaling of frequency during warm-up is substantially further still from predictions of the model, and in these circumstances the fundamental harmonic frequency probably is not realized. 4. Among flying insects generally, the fit to the oscillator model is somewhat better than in dragonflies alone and is markedly improved if differences in wing-loading are also taken into account. 5. Linear regressions of frequency onTb fit the data about as well as exponential regressions. Regardless of the regression model used, temperature sensitivity of wingstroke frequency during flight is lower than that of most biological processes. The difference in temperature response between warm-up and flight frequencies is consistent with the different functions of these behaviors. 6. During warm-up the quantity of heat produced per wingstroke increases with increasingTb in small but not in large dragonflies.

Supraoptimal Temperature Effects upon Agrostis palustris

Abstract Agrostis palustris sods were grown sequentially in a controlled environment chamber at 20–10, 25–15, 30–20, 35–25, and 40–30°C day‐night temperature regimes. Leaves grown at 40–30°C contained 53% more ethanol soluble and 51% more water soluble carbohydrate than those grown at the 4 lower temperature regimes. The increase in ethanol and water soluble carbohydrate in leaves at 40–30°C could not be attributed to a blockage in translocation of photoassimilate to lower plants parts based on quantitative carbohydrate analyses on stem and stolon tissue.Manometric measurements of photosynthesis indicated that leaf blades grown at the five temperature regimes exhibited different rate capabilities when tested under non‐limiting light and carbon dioxide levels. Oxygen evolution increased directly with temperature from 20 to 40°C and was 8 to 11 fold greater than the rate of carbon dioxide evolution. Both quantitative and qualitative differences in the photosynthetic rate were postulated in the leaf blade tissue tested. The quantitative difference was attributed to a possible difference in the number of cells per unit area and their size. The qualitative difference was attributed to greater thermal stability of leaf proteins when plants were grown at supraoptimal temperatures.Manometric respiratory rate studies did not indicate similar differences in temperature response in leaf blade tissue grown at the five temperature regimes. The cause of decreased shoot growth at supraoptimal temperatures could not be attributed to decreased and limiting C‐6 carbohydrate synthesis.

The effect of temperature and genetic background on the phenotypic expression of several vestigial strains of Drosophila melanogaster.

The eightvestigial strains,vg, vg-co-iso,vg;se-co-iso,vg-ms-1-co-iso,vg-ms-1; 3-co-iso,vg-ms-co-iso,vg-ms;se andvg-ms;se-co-iso showed various temperature responses. The five strains of thevg-ms group showed a greater response to temperature than did the three strains of thevg group. This tendency became more pronounced the higher the temperature was. The difference in temperature response between thevg-ms-1; 3-co-iso andvg-ms-co-iso strains indicates that the phenotypic expression ofvestigial is influenced by a modifier or modifiers located on the second chromosome of the Oregon(iso) strain. It was found that the X chromosome of the Oregon(iso) strain showed a slight modifier action in females but not in males of thevg-ms mutant.

Thermal Acclimation and Peptic Digestive Capacity in the Black Bullhead, Ictalurus melas (Raf.)

A study was carried out to determine whether the black bullhead demonstrates a compensating peptic digestive capacity influ- enced by thermal acclimation. Crude pepsinogen extracts from entire stomachs of two groups of fish were used. One group was acclimated to 12C, the other group to 24C (all for more than 60 days). It was found that the extract from the group of fish acclimated to 24C showed higher peptic activity than that from the 1 2C acclimated fish. The high peptic activity in the 24C acclimated fish group seemed to repre- sent a reversed compensation. A slight difference between responses to substrate pH was observed. There were no detectable differences in temperature responses between the peptic extracts from the two labora- tory-acclimated fish groups. It was concluded that black bullheads probably have greatest digestive capacity during the summer months. During the winter they most likely exist at reduced activity levels on stored fat and glycogen. The results of previous investigations on digestive capacities in poi- kilotherms have varied with the species and with the particular digestive enzyme under investigation. Mews (1957) found that Carassius carassius (Lin.) had greatest alkaline proteolytic activity after being acclimated to summer temperatures. Leonard (1941) found that the feces of brook trout captured during the winter were made up of an undigested mass of organisms, some of which were alive. Amia calva Lin. and species of Lepomis have lower digestive capacities during the winter than during the summer (Riddle, 19095. The salamander, Necturus sp., was found to have a higher digestive capacity in December than in March. Riddle compared his findings with those of Gillespie (quoted by Riddle) who had found that the

The effect of temperature on mitosis and on the action of colchicine in root meristem cells of Vicia faba

1. 1. The effect of temperature on the mitotic rate, and on the duration of mitotis and the mitotic cycle, in Vicia faba root meristem cells, has been studied by means of the colchicine technique. 2. 2. The relative change in the duration of mitosis and of interphase are shown to differ with change in temperature. This difference in temperature response between these parameters results in differences in the Mitotic Index at the different temperatures. 3. 3. The rate of cell progress, or mitotic rate, throughout the mitotic cycle increases linearly with increase in temperature between the range 3 °C to 25 °C. 4. 4. The effect of an increase in temperature on the action of colchicine is expressed in two ways. Firstly by a reduction in the time required before colchicine effectively blocks all cells at metaphase, i.e. a reduced lag time, and secondly by the more rapid expression of the toxic action of the drug.

The magnetochemistry of vitamins

Freezing is a limiting factor for plant life, as it can cause damage of living tissues and embolism formation in conduits. Ice formation in plant tissues is usually detected by exotherm analysis. In this study, a new method based on changes in ultrasonic properties of wood was used to monitor xylem freezing. Ultrasound propagation velocities and attenuation were measured with an ultrasonic emission analysis system in branches of three conifer and three angiosperm tree species by signal induction via auto sensor test (AST) or lead break (LB: Hsu–Nielsen source). In all species under study, ultrasound velocity was 1.2–3.6-times higher in frozen xylem (−10 °C) compared to samples at 10 °C. In Picea abies, velocities of AST signals increased from 2193 to 3085 m s−1 and in Fagus sylvatica from 2369 to 3009 m s−1, while signal attenuation decreased in both species. The crystalline structure of ice with slower molecular movements and strong hydrogen bonding caused the faster propagation and reduced attenuation of acoustic waves after xylem freezing. Xylem anatomy also influenced acoustic properties as demonstrated by inter-species differences in temperature responses. The analysis of ultrasonic properties provides a new method for the detection of ice in the xylem of trees and may be used to monitor stress intensities and estimate physiological effects in situ.

Temperature Tolerance in Young Pacific Salmon, Genus Oncorhynchus

Lethal limits of high and low temperatures were determined for the young of five species of Pacific salmon, the spring (Oncorhynchus tshawytscha), the pink (O. gorbuscha), the sockeye (O. nerka), the chum (O. keta) and the coho (O. kisutch).For acclimation temperatures ranging from 5° to 24 °C. significant differences between species in their resistance to high temperatures was obtained. The spring and coho were most resistant. The pink and chum salmon were least resistant, and the sockeye was distinguishable from the latter two by greater resistance for prolonged exposure to high temperatures. No species could tolerate temperatures exceeding 25.1 °C. when exposed for one week.A fanning-out of the opercula was shown to be directly correlated with the onset of death from a low temperature. By use of this criterion mixed lethal effects at low temperatures were demonstrated and found to be influenced by the size of the fish and by the salinity of the water. None of the species could withstand temperatures lower than 4 °C. when acclimated to 20 °C. and above. When taken from holding troughs as low as 5 °C., coho and sockeye could not tolerate long exposure (four days) to 0 °C.In a vertical gradient little difference in preferred temperature was observed, either between species or for different acclimation temperatures. The 12° to 14 °C. stratum was the region of greatest concentration.Specific differences in temperature responses are in keeping with taxonomic and ecological distinctions.