<p> This work contributes to the study of magnetic interactions in the low-dimensional antiferromagnets <i>M</i>(Sb,Ta)₂O₆, where <i> M</i> is a transition metal. By virtue of the trirutile structure, <i> M-O-O-M</i> chains propagate along [110] at <i>z</i> = 0 and [1<span style="text-decoration:overline">1</span>0] at <i>z</i> = 1/2 of the unit cell. These chains are separated along [001] by sheets of weakly-interacting diamagnetic ions. The spin-exchange coupling perpendicular to the chains is weak, permitting the low-dimensional classification. Single crystals have been grown using chemical vapor deposition and the floating zone method. Magnetization, in-field heat capacity, and high-resolution thermal expansion measurements have been performed along various axes, revealing significant anisotropy due to the peculiar magnetic structures and low dimensionality.</p><p> The Neel temperature, <i>T_N,</i> at which long-range order occurs is found to be unstable against the application of magnetic field above 2 T. Large fields tend to lower <i>T_N</i> of the set of moments with projections along the applied field. Moments which are aligned perpendicular to the field are significantly less affected. This can lead to the formation of a secondary peak in heat capacity when magnetic field is along either [110] or [1<span style="text-decoration:overline">1</span>0]. The change in heat capacity at the location of the newly formed peak means there is a change in entropy, which depends upon the direction of applied field with respect to the magnetic moments. Consequently, an anisotropic magnetocaloric effect arises due to the unique magnetic structure. The anisotropic nature of this effect has potential applications in magnetic refrigeration.</p>

Class of 2009 Abstract / OBJECTIVES: The objective of this study was to investigate the effects of temperature excursions on insulin during standard shipping from mail-order pharmacies. METHODS: Twelve vials of insulin (six of regular and six of neutral protamine hagedorn (NPH)) were sampled at baseline and then the six experimental vials (three regular and three NPH) were shipped through the mail system from a Tucson, Arizona post office to a Tucson, Arizona residence. The other six vials were used as controls and left in a refrigerator at 5°C. Samples were taken daily and then measured for degradation using high performance liquid chromatography (HPLC). Also, samples from control vials were put in a lab oven at a constant temperature of 48°C and analyzed at Day 0 and Day 2. RESULTS: Temperatures spiked daily to near or over 50°C with a peak of 51.5°C. The low temperature never dropped under 21°C. The area under the curve (AUC) for each individual sample drawn was used to calculate a percentage of its original concentration with Day 1 set as 100%. On Day 6, both experimental vials and control vials had similar results and were within 10% of the original concentrations measured. In the oven, NPH samples that were heated for two days lost about 4% of its concentration while the regular insulin sample lost 14%. Particle sizing data of regular insulin heated in the oven was consistent with this HPLC data, and showed significant shifts in peak position. CONCLUSIONS: Insulin appears to maintain its stability after being shipped through the mail and remaining in a mailbox for an additional five days at high summer temperatures in Arizona. However, when exposed to constant high temperatures in a laboratory oven, heat appears to affect its stability.

Correlative and regression analyses of daily ERA-Interim reanalysis data for three separate solarmaximum periods confirm the existence of a temperature response to short-term (mainly ∼27 day) solarultraviolet variations at tropical latitudes in both the lower stratosphere and troposphere. The response,which occurs at a phase lag of 6–10 days after the solar forcing peak, consists of a warming in the lowerstratosphere, consistent with relative downwelling and a slowing of the mean meridional (Brewer-Dobson)circulation, and a cooling in the troposphere. The midtropospheric cooling response is most significant inthe tropical Pacific, especially under positive El Niño–Southern Oscillation conditions and may be relatedto a reduction in the number of Madden-Julian oscillation events that propagate eastward into the centralPacific following peaks in short-term solar forcing.

The extent of weathering incongruency during soil formation from rock controls local carbon and nutrient cycling in ecosystems, as well as the evolution of hydrologic flow paths. Prior studies of basalt weathering, including those that have quantified the dynamics of well-mixed, bench-scale laboratory reactors or characterized the structure and integrated response of field systems, indicate a strong influence of system scale on weathering rate and trajectory. For example, integrated catchment response tends to produce lower weathering rates than do well mixed reactors, but the mechanisms underlying these disparities remain unclear. Here we present pore water geochemistry and physical sensor data gathered during two controlled rainfall-runoff events on a large-scale convergent model hillslope mantled with 1 m uniform depth of granular basaltic porous media. The dense sampler and sensor array (1488 samplers and sensors embedded in 330 m(3) of basalt) showed that rainfall-induced dissolution of basaltic glass produced supersaturation of pore waters with respect to multiple secondary solids including allophane, gibbsite, ferrihydrite, birnessite and calcite. The spatial distribution of saturation state was heterogeneous, suggesting an accumulation of solutes leading to precipitation of secondary solids along hydrologic flow paths. Rapid dissolution of primary silicates was widespread throughout the entire hillslope, irrespective of up-gradient flowpath length. However, coherent spatial variations in solution chemistry and saturation indices were observed in depth profiles and between distinct topographic regions of the hillslope. Colloids (110-2000 nm) enriched in iron (Fe), aluminum (Al), and phosphorus (P) were mobile in soil pore waters.

This thesis examines the roles of endothermy and body size in the thermal biology of solitary bees (Hymenoptera: Apoidea) within the species Anthophora plumipes (Anthophoridae) Amegilla sapiens (Anthophoridae) and Creightonellafrontalis (Megachilidae), within the genus Anthophora, and over the Apoidea as a whole. The effects of body size, climate and sexual interactions on the biology of Anthophora plumipes were investigated in Oxford between 1987 and 1989. Both ambient temperature and body size had a significant effect on females' ability to forage, what time they initiated foraging in the morning, and the type and mass of provisions collected. The behaviour of males was also strongly dependent on ambient temperature, which affected not only when they emerged from their nest tunnels, but also how long they spent basking, when and where they fed, and whether they showed courtship behaviour. The activity patterns and behaviour of male and female A. plumipes over time were shown to correlate with a complex array of factors. Activity patterns of females depended on the quality of floral resources available at foraging sites, body mass, ambient temperature, the position of the female in her nest-provisioning cycle, and levels of male interference at foraging sites. Male behaviour not only depended on body size and ambient temperature, but also on which other bees (particularly male and female conspecifics) were encountered while patrolling food sources and at the nest site. Endothermy in bees is much more widespread than previously thought, and warm-up before flight was present to some degree in all the species examined. Levels of thermoregulation achieved, however, varied considerably between species. Warm-up rates in bees, and thoracic temperatures in free and tethered flight, are shown to depend on ambient temperature and body mass within a species (for temperate and tropical examples), across members of the genus Anthophora and across the Apoidea as a whole. The persistence of these relationships over a range of comparative levels suggests that they are of fundamental importance. The form of these relationships differs between families in the Apoidea, and significant patterns only emerge when a comparative technique controlling for phylogeny is applied. Furthermore, body temperatures may also depend, in at least some cases, on sex and there may be differences within a group of related species between provisioning and parasitic forms. The interaction of all these factors is complex, and the predictive value of a variable such as body mass does not always emerge unless sophisticated techniques are used to control for other variables. The errors associated with two common methods in the measurement of insect body temperatures have often been loosely discussed but rarely quantified. This thesis examines (a) the magnitude and possible effects of errors in 'grab-and-stab' measurement of body temperature, and (b) the errors in measurement of body temperature using fixed sensors linked by thermally conducting leads to measuring devices. In neither case do the demonstrated errors preclude use of the technique, but care with interpretation is required. In both cases, measurement of thoracic temperature in small bees involves the largest errors, and this is the most serious obstacle to comparisons of endothermic and thermoregulatory abilities over the full range of body sizes found in the Apoidea.

One of the purposes of this work is to investigate modifications that have to be made to a standard source-modulation microwave spectrograph so that it can be used to study gases at various temperatures. Another objective in this work is to determine experimentally the function of temperature that describes how the line widths of microwave spectral lines vary with changing temperature. The most important segment of the study is the temperature dependence of the line width since from an accurate knowledge of this temperature dependence one is able to determine what molecular force fields are present and the relative importance of parts of the molecular force field.

Interference competition is widely considered to structure ant communities. Competition’s effect, however, may be contingent upon disturbance or the abiotic environment. The interaction of temperature and competition is implicit in a wide body of ant community research; however, very few studies have experimentally manipulated these variables. To investigate the role of competition and temperature on ant communities, I (i) employed null models to investigate how species partition their spatial, temporal, and thermal environments in disturbed and undisturbed forests, (ii) used pairwise behavioral experiments to construct a Markov chain model to predict relative abundance patterns and correlated behavioral indices to species co-occurrence patterns, and (iii) conducted a shade, physiological thermal tolerance, and fully factorial shade and removal experiment to investigate the interaction of competition and temperature on ant community structure. The results of these studies are summarized below. First, I took advantage of a natural experiment, the 2002 Biscuit Fire, to investigate how species partition their temporal, thermal, and spatial environments in disturbed and undisturbed forests with null models. I found that most sites displayed a high degree of temporal niche overlap and species aggregation along the thermal axis. Half of the sites, however, had regular spacing of the temperature at which species obtain maximum activity. Species co-occurrence patterns in space modulated with diurnal temperature variations. Unburned sites had more spatial segregation of species than burned sites. Overall, it appears as though species activity is regulated, at least in part, by the thermal niche axis, and ant communities may repeatedly assemble and disassemble throughout the day. Second, I used data from pairwise behavioral experiment to generate transition probabilities for a Markov chain model. Assuming the landscape represents a large number of patches, the model predicted the relative abundance of an assemblage. I compared Markov chain predictions of relative abundance to relative abundance measurements on the local and regional scale. I used the same pairwise behavioral data to predict species co-occurrence values in three sites. Neither model accurately predicted community patterns. The only significant result was the Markov chain prediction of bait occurrence on the local scale; however, the relationship was opposite of the prediction. Finally, I conducted a shade experiment to investigate how communities respond to an altered thermal environment and associated their response to results from physiological thermal tolerance experiments. I then conducted a fully-factorial shade and Formica moki removal experiment to investigate if thermal responses were mediated by competitive effects. The addition of shade tables greatly reduced temperatures in the field, and Temnothorax nevadensis abundance was consistently lower in shade treatments. Decreased abundance at shade stations did not appear to be an indirect effect of F. moki activity. Physiological thermal tolerance was strongly associated with changes in abundance in shade treatments: the lower a species thermal tolerance, the greater its positive change in abundance after shade additions. The only species with a strong foraging response to F. moki removal was T. nevadensis, a species who was often cooccurred with F. moki on baits. I did not find evidence for the interaction of competition and temperature, and it appears as though physiological differences strongly influence the foraging activity of Siskiyou ant communities.

The change of ionospheric absolute reflection heights h of low-frequency (LF) radio waves at oblique incidence in the course of the day is measured at Collm Observatory (51.3°N, 13.0°E) using 1.8 kHz sideband phase comparisons between the sky-wave and the ground wave of a commercial 177 kHz transmitter (Zehlendorf, reflection point 52.1°N, 13.2°E). Plasma scale height estimates H are calculated from the decrease/increase of h in the morning/evening. The day-to-day variations of H are compared with those of daily mean temperatures at 90 km, measured with a VHF meteor radar (36.2 MHz) at Collm utilising the amplitude decay of meteor reflections. A good qualitative correspondence is found between the two data sets. Since mesospheric long-period temperature variations are generally accepted to be the signature of atmospheric planetary waves, this shows that LF reflection height measurements can be used for monitoring the dynamics of the upper middle atmosphere.

In 2010 the housing stock was responsible for 30.5% of all energy consumed in the UK. The UK government has set a transition target to reduce the energy used from space heating in dwellings by 29% by 2020 as part of their drive to lower CO2 emissions and mitigate the risks of global climate change. Housing stock energy models have been developed as research tools to identify pathways to a low energy future. These tools use assumptions about how homes are heated that may reduce their effectiveness at making accurate energy predictions. This thesis describes the collection and analysis of temperature data from over 300 homes in Leicester to develop better understanding of how dwellings are heated. The temperature measurements were assessed for error and a final sample of 249 dwellings was established. Mean winter temperatures (December February) were found to be 18.5°C and 17.4°C for living rooms and bedrooms which are comparable with temperatures reported in previous studies. Statistically significant relationships were established between seven descriptors; three technical (house type, house age and wall type) and four social (household size, employment status, age of oldest occupants and tenure). Only 24% of the variation in mean winter temperature could be explained by these descriptors. Ten heating practice metrics were developed to give insight into how homes are heated; these included the duration of the heating period and the average temperature when heated. Statistically significant relationships were found between the heating practices and a number of technical and social household descriptors. It is concluded that the variation in heating practices which relates to social household descriptors will result in models being unable to make accurate predictions at the regional of city scale. Furthermore, this work has shown flaws in the idealised temperature profile as used in BREDEM. It is suggested that the findings of this work are considered in the development of future stock models.

INTRODUCTION: Cardiovascular drift is a phenomenon, which appears after 10 - 20 minutes of prolonged moderate - intensity exercise (50 - 75% VO2max). CVD appears in a neutral or hot environment. It is characterized by a decline in stroke volume and systemic mean arterial pressures and a parallel increase in heart rate. Cardiac output is maintained nearly constant. The theory of CVD shows increase of core temperature and sympathetic nervous system as cause of increase of heart rate. GOALS: The goal of this thesis was find out the change of heart rate depending on time. Then we found out changes of oral, tympanic, axillary, vaginal and superficial skin temperature. We found out correlation between vaginal temperature and heart rate and then between skin temperature and vaginal temperature. METHODS: Blood pressure, heart rate, oral, tympanic, axillary, vaginal and superficial skin temperature were measured during 60 minutes of cycling (intensity 55% VO2max; 1,99 ± 0,14 W/kg). It was measured at 13 women (25,5 ± 1,3 years; 69,1 ± 7,7 kg). RESULTS and CONCLUSION: There was statistically significant increase of heart rate compared to value from 10. minute. during. There was increase of tympanic temperature compared to value from 10. minute only at the end of exercise. There was significant increase of vaginal and...