I. CURRENT FLUCTUATIONS IN A SUPERCONDUCTING CIRCUIT CARRYING A CIRCULATING CURRENT - Persistent currents in superconducting lead are free from fluctuations to less than 1.1 x 10⁻⁹ of full shot noise at approximately 2.4 Mc/s. Superconducting currents are also unaffected by the surface condition of the metal to the same limit as stated above. II. A NEW ABSOLUTE NOISE THERMOMETER AT LOW TEMPERATURES - If three resistors, which are kept at different temperatures, are arranged in form of a π network and if two of the thermal noise voltages appearing across the if network are multiplied together and averaged with respect to time, then under certain conditions the correlation between those voltages can be made zero. This condition is used to calculate the temperature of one noise source provided all the resistance Values and the other temperatures are known. A noise thermometer of this kind was constructed which is capable of measuring temperatures below approximately 140°K. The boiling points of liquid oxygen and liquid nitrogen were determined absolutely within 0.2 percent using the ice-point as reference. Between 1.3°K and 4.2°K the thermometer had to be calibrated due to errors arising in the equipment and the measured temperatures were then accurate within ± 1 percent. III. QUASI-PERSISTENT CURRENTS IN RINGS COMPOSED OF SUPERCONDUCTING AND NON-SUPERCONDUCTING REGIONS - A number of rings composed of a superconductor (Pb, In) apart from a small insert of normal metal (Cu) perpendicular to the current flow have been investigated between 1.30°K and 4.33°K for Pb-Cu and between 1.30°K and 3.20°K for In-Cu. It was found that for samples with good electrical contact the decay of the magnetic field due to the current is exponential and that the effective resistance increased compared with the bulk resistance of Cu by approximately 2.1 for the Pb-Cu rings and by 18.5 for the In-Cu rings. Two different thicknesses of the Cu inserts (0.0125 cm and 0.0053 cm) were used and it was found that the resistivity of the thin Cu insert increased with respect to the thick foil by 16% for the Pb-Cu system and by 36% for the In-Cu system. Part of this relative increase can be explained as a size effect due to electron scattering in the Cu insert. The effective resistance of the Pb-Cu rings shows a maximum at approximately 3.4°K. The resistance of the In-Cu samples decreases by about 10% between 3.2°K and 1.3°K. The resistivity of the Cu foil when measured separately was constant for the above temperature range. For samples with "poor" electrical contact (probably due to some copper oxide on the insert) two definite relaxation times were observed. For these samples the effective resistance was current and temperature dependent and it was decreasing for decreasing currents and decreasing temperatures. This can be explained in terms of a rectification effect of the two oxide layers on the insert. The decay of the magnetic field of the ring is consistent with the decay of a current in an L-R circuit. IV. THE DESTRUCTION OF SUPERCONDUCTIVITY IN TANTALUM WIRES BY A CURRENT - The transition from the superconducting to the normal state of various pre-stretched tantalum wires carrying current was investigated. When the resistance of the wire jumps discontinuously from the superconducting to the normal or intermediate state as a current is passed through it, then this current is defined as the critical current I(c). For temperatures T < (T(c)-5 millidegrees K) the resistance of the wire jumps directly from zero resistance to its normal value at the critical current, such that the total cross section of the wire goes effectively into the normal state. Between (T(c)-5 millidegrees K) and T(c) the resistance of the wire jumps at I(c) to any fraction of the normal resistance between approximately zero and one. For constant temperatures the resistance-current plots show a large hysteresis effect. The transition temperature, T(c), of the various samples is strongly dependent upon their normal resistivity at helium temperatures. If the wires with a small constant current (4.2 ma) flowing in them are cooled from above the transition temperature, the resistance decreases above T(c) and approaches zero at approximately T(c) where T(c) is defined by the extrapolation of the I(c)-T curve to I(c) = 0. If the wires are heated from below T(c) the same resistance-temperature curves are reproduced. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

During the summer of 1969 a thermal drilling and deep ice-temperature measurement program was carried out on the Fox Glacier, Yukon Territory. The thermal drilling resulted in seven instrumented holes at six locations on the glacier, three reaching bedrock. Temperature measurements indicated that the glacier was below the pressure-melting point throughout and that memory of a disturbed thermal regime existed. Estimates of geothermal heat flow were determined and an anomalous value of 4.73 μcal/cm² sec obtained. Bottom temperature models were developed which indicate the possibility of basal melting. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

Temperature and heat transfer studies in a pilot-scale water immersion retort were performed. The temperature study investigated the temperature distribution and stability of the retort during the cook period. The investigation of heat transfer uniformity within the retort was based on heating and cooling parameters calculated from the heat penetration curves of food-simulating teflon transducers. The uniformity of sterilizing conditions within the retort was determined from process lethalities calculated for the transducers. Variable retort operating conditions consisted of two retort temperatures (115 and 125°C) and three weir heights (29.2, 31.2 and 34.6 cm). Mean standard deviations of thermocouple readings indicating temperature distribution during the cook period ranged from 0.19 to 0.22 C°. Slight temperature gradients were found between the upper and lower water channels and between the entrance and exit regions of water channels. The coldest locations (the exit regions of water channels 1 and 2) averaged approximately 0.6 C° lower than the hottest locations (the entrance and exit region of water channel 11 and the exit region of water channel 10). Mean standard deviations of thermocouple readings indicating temperature stability during the cook period ranged from 0.10 to 0.20 C°. Temperature stability was uniform between all water channels, except channel 11, which was less stable. The entrance and exit regions of water channels displayed similar stability. The existence of heat transfer variability within the water immersion retort was indicated. A retort temperature of 125°C produced smaller fh and fc values than 115°C. Variations in weir height influenced the distribution of fh values between trays. Weir height 2 (31.2 cm) exhibited uniform values between all trays. Weir height 1 (29.2 cm) exhibited uniform fh values between all trays, except for a significantly larger value for the very top tray. Although weir height 3 (34.6 cm) created the most variability between tray levels, weir height 1 displayed the widest range of fh values. More variability in fc values between trays was shown during the cool period. Weir height 2 displayed the most uniform fc values between trays, however, the range of fc values between trays was similar for all three weir heights. Within trays, a gradient of fh and fc values was found between the entrance, exit and middle positions, with the smallest values found in the entrance positions. In comparison, the largest fh values were found in the exit and middle positions of trays 1 and 10. The largest fc values were found in the middle positions of trays 1 and 3 and the middle and exit positions of tray 10. Weir heights 1 and 2 produced smaller jh values than weir height 3, variations in weir height had no influence on jc values. A gradient of jh values between tray levels was shown, with smaller values associated with upper trays and larger values with lower trays. Smaller jh and jc values were associated with the entrance positions of trays than with the middle and exit positions. A comparison with steam processing indicated larger fh values for the water immersion process and larger fc values for the cooling method used with the steam process. Calculation of process lethalities indicated variability of sterilizing conditions within the retort. Larger Fo values were associated with upper trays than with lower trays. Within trays, larger Fo values were found in the tray entrance positions than the middle and exit positions. The largest Fo values were exhibited in the entrance positions of the middle to upper trays, while the smallest values were found in the middle and exit positions of the bottom trays. Retort pressure studies indicated pressure stability during the cook period, however, during the initial minutes of the cool period, a significant pressure drop occurred, which the retort corrected. Pressure stability was maintained once the target pressure was re-established. / Land and Food Systems, Faculty of / Graduate

This project deals with design of universal system for temperature stabilization using a Peltier device, controlled by microcontroller. The result of this work is an autonomous equipment with automatic tuning of regulation constants, calculation of temperature stabilization limits, possibility of setting required modes and with interface for connection to PC. The regulator stabilise temperature with an accuracy of 0,1 °C within the range of temperature from 0 to 60 °C.

Bibliography: pages 143-154. / The relationships between interannual sea surface temperature variability (SST) of the oceans surrounding southern Africa and summer rainfall variations over South Africa are investigated using statistical, observational and mechanistic approaches. Positive correlations are identified between summer rainfall and SSTs of the Mozambique/ Agulhas Current region, the Agulhas Retroflection region and the northern Benguela Current system. These relationships are stronger when rainfall anomalies associated with the Southern Oscillation are not considered. The observation of significant lag relationships involving temperatures of the Agulhas Current system suggests that future prediction efforts for summer rainfall will benefit from a consideration of SST anomaly patterns east and south of Africa, in combination with other atmospheric indices. Surface winds, heat fluxes and atmospheric boundary layer characteristics are investigated using compositing analyses to assess pertinent ocean-atmosphere coupling mechanisms. Easterly wind anomalies across the southwest Indian Ocean and over source regions of the Agulhas Current accompany and precede the local oceanic "warm events" which correspond with higher rainfall. Thus a class of event is identified in which warmer waters along the east coast and stronger easterly wind forcing accompany wetter seasons over South Africa. The atmospheric boundary layer is considerably warmer and moister in association with positive SST anomalies along the east coast and increased tropical airflow. Consequently, moisture convergence and tropical convection are increased over the eastern interior near 20° to 25°S. South of Africa, positive SST anomalies generate surface heat flux anomalies, increasing instability and moisture levels within the boundary layer. Horizontal heat flux gradients are strengthened across the Agulhas/Subtropical Convergence SST front and the conditions necessary for cyclogenesis and westerly wave amplification are optimized. Tropical-temperate troughs account for most of the abnormal rainfall during local Agulhas "warm events". The presence of positive SST anomalies east and south of southern Africa increases the likelihood of their formation by intensifying tropical and temperate components. The contribution provided by each component is influenced by the position and magnitude of the SST anomaly as well as the season of occurrence. Conceptual models are presented which summarize the most important ocean-atmosphere coupling mechanisms associated with rainfall variations of southern Africa.

Erythromelalgia is a rare clinical syndrome characterized by heat, redness and intermittent pain in the extremities, being most frequent the bilateral development in the lower extremities. Local cooling brings relief to symptoms, while heating, physical exercises and use of stockings/socks intensify the discomfort. This condition can be primary or idiopathic or secondary to haematological disorders and vascular inflammatory and degenerative diseases. It is reported the case of an eighteen-year-old male who presented, at the early age of two, development of the symptoms of erythema, heat and pain followed by desquamation of hands and feet, in outbreaks, with intervals 4 to 5 years long between the crises.

Technological advances in clinical thermometers have resulted in a variety of minimally invasive devices that give rapid results but may not have the accuracy necessary for use in acutely ill adults. Inaccurate temperatures can result in missed opportunities for the early identification and treatment of infection and sepsis. Following the methodology outlined by Whittemore and Knafl, the purpose of this project was to conduct an integrative review of the research on the accuracy of clinical thermometers used for acutely ill adults. The evidence was categorized using the Hierarchy of Evidence for Interventional Studies, and the quality of the studies was appraised using the indicators described by Hooper and Andrews. Forty-seven studies met the inclusion criteria; the findings on device accuracy were contradictory. Device accuracy was found in 10 (n = 27) studies on the tympanic (TM), 2 (n = 8) on the chemical dot (CH), 7 (n = 19) on the temporal artery (TAT), and 3 (n = 13) on the axillary (AX) thermometers. Two of 2 studies found the no-touch (NT) device clinically inaccurate. Diagnostic accuracy was found in 3 (n = 8) and 0 (n = 5) studies on the TM and TAT, respectively. Only 22 studies had an acceptable quality grade of A or B, limiting the validity of the evidence. The evidence did not support the use of the NT and TAT thermometers or the AX route for acutely ill adults. The CH device should be use with caution, and abnormal temperatures should be validated with a more reliable device. For thermometers in use, appropriate training and technique are essential for the most accurate results. Closing the knowledge-to-practice gap on clinical thermometers can change the culture of nursing practice, improve early sepsis identification, and increase the quality of patient care.

A group of red-eared turtles (Pseudemys scripta elegans) was acclimated to 18-20˚C and artificial photo-period for 21 days. The animals were then individually placed in a thermal gradient and their selected temperatures were continuously recorded for 24 hours. A second group of turtles was acclimatized to 7.5-11.0˚C and natural photoperiods for 28 days, and subsequently tested in the same manner as the first group. Lastly, the turtles in the first group, after being acclimated to 3.0˚C and the previous artificial photoperiod for 14 days, were retested in the gradient.

Cotton production came to a halt in Southern Illinois in 1974 after the last crop was harvested. Many factors went into the death of cotton in Southern Illinois. My dissertation addresses the factors that halted cotton production in 1974, and new technologies that will enable farmers to grow cotton again in 2019. Temperature and rainfall are two important factors that affect the growth of cotton. Once cotton is re-introduced into Southern Illinois, an infrastructure with a well-trained workforce will need to be in place to sustain this new industry. This study was motivated by three research goals and questions: (1) Have Southern Illinois temperatures increased or decreased over the last 50 years? Specifically has Growing Degree Days or Heat Units increased over the last 50 years creating a more suitable environment for cotton production in Southern Illinois? (2) Was rainfall a limiting factor in the death of cotton in 1974 and the revival in 2018? How has rainfall changed in Southern Illinois over the last 50 years? (3) What impact would the cotton industry have on the Southern Illinois workforce? Specifically, what would education and training for a new cotton industry entail?

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