The ecology of Cheimophila salicella Hbn. (Lepidoptera: Oecophoridae), a blueberry leaf-tier was studied on high-bush blueberry, Vaccinium corymbosum L., in Richmond, British Columbia. The females frequently laid their eggs in the lichen Xanthoria sp., an oviposition site not previously reported for this species. The possible microclimatic advantages of such behaviour are discussed. In the Field, females required longer than males to complete their 6th instar, so females were usually bigger than males in that instar. The leaf shelter made by the larvae modified their microenvironment in the field. On clear and sunny days, measurements of shelter temperature were 6-7°C above those of ambient air. The shelter temperature remained warmer than the air as long as the incoming radiation levels were high. As the radiation levels dropped, the shelter temperature fell to, or a little below, air temperature. On cloudy days, there was no significant difference between the daily maximum shelter and air temperatures. Under clear skies, the daily amplitude of temperature fluctuations was greater inside the shelter than outside. A laboratory investigation of the effects of such fluctuations on development showed that a large amplitude increased the developmental rate of the lst-4th instars. This increase in rate of development was probably due to an accumulation of extra thermal units (Yeargan 1980) occurring in the large-amplitude regime. However, the high temperature of this regime retarded pupation, and the later instars required longer to complete their development. Overall, larvae in the small and large amplitude regimes required the same amount of time to develop from hatching to pupation. A third regime, "medium amplitude", slowed larval development, probably because the length of its thermophase was longer than that which the insect normally encountered in the field. Fifth- and sixth-instar females took longer than males to complete their development, both in the laboratory and in the field. The larger amplitude regime produced heavier pupae; females were, on average, 12.7 mg heavier than males. The microclimate of the shelter provides the larvae with more degree-days than if they were subjected to ambient air and therefore promotes faster development. Without the extra degree-days provided by the shelter, C. salicella would not be able to complete its larval development before the first lethal autumn frost. / Land and Food Systems, Faculty of / Graduate

A total of 670 critical thermal maxima (CTMax) and minima (CTMin) were determined for three freshwater fishes acclimated to three constant temperatures and a diel regimen cycling between the lowest and highest acclimation temperatures. In all species temperature tolerance was directly related to acclimation temperature and slopes relating these variables indicate that acclimation temperature has a greater influence on tolerance of low rather than high temperatures. CTMax and CTMin values generated following exposure to 32 days of oscillating temperatures indicate that in general, fishes had temperature tolerance acclimation states consistent with the average temperature and not either the highest or lowest temperature of the diel cycle.

In Pyrococcus furiosus (Pfu), a hyperthermophile archaeon, two transcription factor Bs, TFB1 and TFB2 are encoded in the genomic DNA. TFB1 is the primary TFB in Pfu, and is homologous to transcription factor IIB (TFIIB) in eukaryotes. TFB2 is proposed to be a secondary TFB that is compared to TFB1, TFB2 lacks the conserved B-finger / B-reader / B-linker regions which assist RNA polymerase in transcription start site selection and promoter opening functions respectively. P. furiosus, like all Archaea, encodes a single transcription factor E (TFE), that is homologous to the N-terminus of transcription factor II E (TFIIE) α subunit in eukaryotes. TFE stabilizes the transcription bubble when present, although it is not required for in vitro transcription. In this study, in vitro transcription is used to reveal how TFB2 responds to different temperature (65 °C, 70 °C, 75 °C, 80 °C, and 85 °C) at promoters for three different kinds of gene: non-temperature responsive, heat-shock induced, and cold-shock induced in the absence or presence of TFE. The activity of transcription complexes formed by TFB2 is always lower than by TFB1 in all temperatures and promoters. However, with heat-shock gene promoters, the activity of transcription complexes formed by TFB2 increases more than those formed with TFB1 with increasing temperatures. The temperature-dependent activities of TFB1 and TFB2 are similar with the non-temperature responsive gene promoter. With the cold-shock gene promoter, the activity of transcription complexes formed by both TFB1 and TFB2 has the highest activity in lower temperatures. When TFE is present, the activity of transcription complexes formed by TFB2 is enhanced with heat-shock gene promoters particularly at lower temperatures, and makes TFB2 behave more similarly to TFB1. With the non-temperature responsive gene promoter, TFB2 still behaves similarly to TFB1 when TFE is present. However, with the cold-shock gene promoter, most of the activity of transcription complexes formed by TFB1 and TFB2 remain the same, but only the activity of TFB1 decreases at 75 °C. The results suggest that TFB2 may play a role in heat-shock response through its increased sensitivity to temperature, and that TFE can modulate this temperature response.

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Uncertainty in accurately knowing applied internal heat transfer coefficients inside of a cooling passage can lead to variability in predicting low cycle fatigue life of a turbine vane or blade. Under-predicting a life value for a turbine part can have disastrous effects on the engine as a whole, and can negate efforts in innovative design for advanced cooling techniques for turbine components. Quantification of this fatigue life uncertainty utilizing a computational framework is the primary objective of this thesis. Through the use of probabilistic design methodologies a process is developed to simulate uncertainties of internal heat transfer coefficient, which are then applied to the aft section of a non-rotating turbine blade component, internally cooled through a multi-pass serpentine channel. While keeping all other parameters constant internal heat transfer coefficients are varied according to a prescribed uncertainty range throughout the passages. The effect on the low cycle fatigue life of the airfoil is then evaluated at three discrete locations: near the base of the airfoil, towards the tip, and at mid-span. A generic low cycle fatigue life prediction model is used for these evaluations. Even though the probabilistic design process uses independent random numbers to simulate the variation, in reality, heat transfer coefficients at points located closely together should be correlated. For this reason, an autocorrelation function is implemented. By changing the value of this function the strength of the correlation of iv neighboring internal heat transfer coefficients to each other over a certain distance can be controlled. In order to test the effect that this correlation strength has on the low cycle fatigue life calculation, low and high values are chosen and analyzed. The magnitude of the prescribed uncertainty range of the internal heat transfer coefficient variation is varied to further study the effects on life. Investigated values include 5%, 10% and 20% for the straight ribbed passages and 10%, 20%, and 40% for both the tip and hub turns. As expected there is a significant dependence of low cycle fatigue life to the variation in internal heat transfer coefficients. For the 20/40% case, variations in life as high as 50-60% are recorded, furthermore a trend is observed showing that as the magnitude of the uncertainty range of internal heat transfer coefficients narrows so does the range of the low cycle fatigue life uncertainty.

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The results of this investigation may serve as the basis for some conclusions with regard to the curing of Portland cement concrete. Some of the more important conclusions are as follows l. A concrete, if it may be classed as such, consisting of fine aggregate, cement, and water, is not subject to the extreme effects of freezing as is a true concrete containing a coarse aggregate. 2. Maximum loss of strength, which is evidently long-enduring is suffered by concrete frozen in an extremely green stage when frost enters mortar paste. 3. Freezing may be harmful at any time within the first week. However, in most cases a recovery is indicated. 4. Steam curing, if not carefully controlled at optimum conditions, will result in loss of strength in a concrete. 5. The expansion and drying which occur at the temperatures in the steam chamber apparently are the cause of harmful results in steam.curing. It must be borne in mind that the limitations of data gathered make these conclusions more indicative than conclusive. There is still much room.for further research at this institution along the line of both problems presented herein. / Master of Science

The effects of temperature and humidity cycling on mechanical properties of AS4/3501-6 quasi-isotropic composites prepared from unstitched, Kevlar 29 stitched, and S-2 glass stitched uniweave fabric were determined. Data presented include compression strengths and compression-compression fatigue results for environmentally cycled and uncycled composites. Ten1perature cycling ranged from 60°C to -55°C. The relative humidity varied between 95 percent at the high temperature and a percent at the low temperature. Microcracks which were found predominantly around individual stitches were recorded using photomicrographs taken at the end of each cycling period. The glass stitched and Kevlar stitched laminates showed significant microcracking before cycling. The unstitched uniweave material developed microcracks only after cycling. The glass stitched material had lower baseline compression strength than the unstitched and Kevlar stitched materials. Temperature and humidity cycling reduced the static compression strength of the unstitched and Kevlar stitched uniweave materials nearly 10 percent. Under the same conditions the glass stitched uniweave material lost 3 percent of its baseline strength. Combined temperature and humidity cycling did not effect the fatigue properties of the uniweave materials when the test specimens were dried to their original weights before testing. / Master of Science