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Living On The Edge-Plants And Global Change In Continental And Maritime Antarctica, Sharon A. Robinson, J. Wasley, A. K. Tobin

Faculty of Science - Papers (Archive)

Antarctic terrestrial ecosystems experience some of the most extreme growth conditions on Earth and are characterised by extreme aridity and sub-zero temperatures. Antarctic vegetation is therefore at the physiological limits of survival and, as a consequence, even slight changes to growth conditions are likely to have a large impact, rendering Antarctic terrestrial communities sensitive to climate change. Climate change is predicted to affect the high latitude regions first and most severely. In recent decades, the Antarctic has undergone significant environmental change, including the largest increases in ultraviolet B (UV-B; 290-320nm) radiation levels in the world and, in the maritime region …

Transport And Survival Of Water Quality Indicator Microorganisms In The Ground Water Environment Of Florida: Implications For Aquifer Storage And Waste Disposal, David E. John

USF Tampa Graduate Theses and Dissertations

Ground water resources are heavily used for drinking water supply and often as a receptacle for waste water. One concern is the possible contamination of wetland areas by ground water receiving septic system infiltration. To investigate this, two tracer studies were performed using the bacteriophage PRD-1 by seeding septic systems adjacent to wetlands with the phage and monitoring migration towards wetland areas. Transport velocities were evaluated based on appearance of tracer in sampling wells at various distances from the injection point. Velocities were estimated to be 0.25 m/d and 0.4 m/d at the two sites. Some retardation with respect to …

Temperature, Stress, And Corrosive Sensing Apparatus Utilizing Harmonic Response Of Magnetically Soft Sensor Element (S), Craig A. Grimes, Keat Ghee Ong

Chemical and Materials Engineering Faculty Patents

A temperature sensing apparatus including a sensor element made of a magnetically soft material operatively arranged within a first and second time-varying interrogation magnetic field, the first time-varying magnetic field being generated at a frequency higher than that for the second magnetic field. A receiver, remote from the sensor element, is engaged to measure intensity of electromagnetic emissions from the sensor element to identify a relative maximum amplitude value for each of a plurality of higher-order harmonic frequency amplitudes so measured. A unit then determines a value for temperature (or other parameter of interst) using the relative maximum harmonic amplitude …

Auroral Source Region: Plasma Properties Of The High-Latitude Plasma Sheet, C. A. Kletzing, J. D. Scudder, E. E. Dors, Carina Curto

Department of Mathematics: Faculty Publications

Statistical results from a survey of 93 passes through the high-latitude extension of the plasma sheet of electron data from the Hydra instrument on the Polar spacecraft show that the values for electron density can range from 0.01 to 0.5 cm^–3 with an average value around 0.1 cm^–3 on the poleward side and 0.3 cm^–3 on the equatorward side. Electron mean energy is found to have an average value near 900 eV on the equatorward side and 400 eV on the poleward side but varies from 100 eV to 4 keV. These values for density and mean …

Epidemiology Of Ustilago Bullata Berk. On Bromus Tectorum L. And Implication For Biological Control, Toupta Boguena

Theses and Dissertations

The seedling-infecting pathogen Ustilago bullata Berk. is a naturally occurring biological control agent for cheatgrass (Bromus tectorum L.). The effects of temperature and nutrients on pathogen teliospore germination behavior and the effects of temperature on host seed germination were examined. The effects of temperature on sporidial proliferation, host infection in a temperature-controlled environment and in a field setting for eight populations were investigated. The infection success of Ustilago bullata on Bromus tectorum in cultivated fields as a function of seeding date, inoculation method, inoculum density, supplemental watering, and litter was also investigated. Teliospores germinated faster on potato dextrose agar than …

Dielectric Permittivity And Electric Modulus In Bi2ti4o11, Jianjun Liu, Chun-Gang Duan, Wei-Guo Yin, Wai-Ning Mei, Robert W. Smith, John R. Hardy

Physics Faculty Publications

Frequency and temperature dependences of dielectric permittivity and electric modulus of pure and Ba-doped Bi2Ti4O11 were studied in the ranges of 1021–106 Hz and 2150–350 °C, respectively. We found that the antiferroelectric phase transition temperature of Bi2Ti4O11 decreases with Ba doping. In the permittivity studies, we also observed dielectric relaxation peaks shift to higher temperature with increasing frequency. Furthermore, in the electric modulus formalism, conducting peaks were uncovered above 150 °C in addition to the dielectric relaxation peak. We discussed the mechanisms for the dielectric relaxation and conduction processes based on TiO6 octahedra distortion and a space-charge model.

Cool Temperatures Elicit Reproduction In A Biologically Invasive Predator, The Brown Treesnake (Boiga Irregularis), Tom Mathies, Lowell A. Miller

USDA Wildlife Services: Staff Publications

Two different temperature regimes for eliciting reproduction in male and females of the Guam form of the brown treesnake were investigated. Males and females maintained at 24°C followed by a 60-day cool period at 19°C exhibited substantial reproductive activity, and the females that produced clutches did so during a brief period after return to 24°C. In contrast, individuals maintained at 28°C followed by an identical 19°C cooling period exhibited relatively little reproductive activity, and although some females became vitellogenic, none produced eggs. Reproductive activity was virtually absent in all individuals in both groups 7 months after the end of the …

Influence Of Storage Duration, Temperature, And Oxygen On Quality Of Stored Dehydrated Foods, Omima Ali Darag

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was undertaken to determine the effect of oxygen absorber packets (OAP) (AGELESS Z.300 E) in improving the shelf-life of selected dried food products, including dried potato pearls, dried sliced apple, dried carrot, white rice, nonfat dry milk, all purpose flour, rolled oats, and wheat. Items were stored at four different temperatures (-20, 10, 21, and 29.5°C) over a period of 24 months with observations at 6-month intervals. Hunter colorimeter, thiobarbituric acid reactive substance (TBARS) germination rate, gluten weight, and volume were parameters used as quality indicators of various dried foods.

Statistical analysis indicated a significant time and temperature …

Influence Of Strain Rate And Temperature Of Hot Tension Testing On Mechanical Properties Of Medium Carbon Steel S48c, Dedi Priadi, Iwan Setyadi, Eddy S. Siradj

Makara Journal of Technology

Influence of Strain Rate and Temperature of Hot Tension Testing on Mechanical Properties of Medium Carbon Steel S48C. The characterization of S48C by hot tension testing was done to understanding the influence of temperature and strain rate for S48C flow stress, that close relationship with its forge ability. The hot tension testing was performed on temperatures and strain rates variation (T 850, 900, 950 0C and έ 0,01;1 s-1). The result of hot tension testing showed that increasing temperature decreases ultimate tensile strength (UTS) and flow stress of S48C. The higher decreasing of UTS is on 950 0C about 85% …

Einstein Oscillators In Thallium Filled Antimony Skutterudites, Raphaël P. Hermann, Rongying Jin, Werner Schweika, Fernande Grandjean, David G. Mandrus, Brian C. Sales, Gary J. Long

Chemistry Faculty Research & Creative Works

Heat capacity measurements were performed on Tl_0.8Co₄Sb₁₁Sn. An Einstein vibrating behavior for the thallium atoms was found. The inelastic neutron scattering measurements on T_0.8Co₄Sb₁₁Sn, Tl_0.5Co_3.5Fe_0.5Sb₁₂, and Tl_0.8Co₃FeSb₁₂ showed a localized vibrational mode, which confirmed this Einstein vibrational behavior. Furthermore, the 56±2 K temperature of the Einstein vibrational mode obtained from the heat capacity measurements showed excellent agreement with the 5 meV energy or 57±2 K values obtained from the neutron scattering measurements.

Two Arabidopsis Circadian Oscillators Can Be Distinguished By Differential Temperature Sensitivity, Todd P. Michael, Patrice A. Salome, C. Robertson Mcclung

Dartmouth Scholarship

Circadian rhythms are widespread in nature and reflect the activity of an endogenous biological clock. In metazoans, the circadian system includes a central circadian clock in the brain as well as distinct clocks in peripheral tissues such as the retina or liver. Similarly, plants have distinct clocks in different cell layers and tissues. Here, we show that two different circadian clocks, distinguishable by their sensitivity to environmental temperature signals, regulate the transcription of genes that are expressed in the Arabidopsis thaliana cotyledon. One oscillator, which regulates CAB2 expression, responds preferentially to light–dark versus temperature cycles and fails to respond to …

Crop Updates 2003 - Geraldton, David Stephens, James Fisher, Ian Edwards, Dennis Wise, Andrew Young, Robert Loughman, Ciara Beard, Greg Shea, Blakely Paynter, Roslyn Jettner, Kevin Young, Kevin Walden, Geoff Thomas, Robin Wilson, Iain Barclay, Robyn Mclean, Jenny Garlinge, Bill Lambe, Neil Venn, Peter Clarke, Martin Harries, Bob French, Wayne Parker, Murray Blyth, Peter Norris, Greg Lyle, Katheryn Steadman, Amanda Ellery, Sally C. Peltzer, Kari-Lee Falconer, Russell Speed, Terry Piper, Harmohinder Dhammu, Bindi Webb, Paul Blackwell, Phil Logue, Nigel Moffat, Rohan Ford, Miles Obst, Frances Hoyle, Leanne Schulz, Judith Devenish, Peter Newman, Grant Morrow, Ian Foster, Darshan Sharma, Marnie Thomas, Graham Walton, Hasan Zaheer, Paul Carmody, Mike Clarke, Paul Raper

Crop Updates

This session covers twenty eight papers from different authors

1. Seasonal Outlook: What is in store for 2003, David Stephens, Department of Agriculture

2. Examining The Management Options For Wheat Crops In The Coming Season, James Fisher, Department of Agriculture

3. GMO’s – what do they offer? Ian Edwards, Grain Bio Tech Australia Pty Ltd

4. The Big Gamble – Wheat prices for 2003, Dennis Wise, Profarmer

5. Market outlook for other grains, Andrew Young, General Manager Agricorp

6. Stripe rust – where to now for the WA wheat industry? Robert Loughman, Ciara Beard and Greg Shea, Department of Agriculture

7. Baudin …

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Disorder-Induced Rounding Of Certain Quantum Phase Transitions, Thomas Vojta

Physics Faculty Research & Creative Works

We study the influence of quenched disorder on quantum phase transitions in systems with overdamped dynamics. For Ising order-parameter symmetry disorder destroys the sharp phase transition by rounding because a static order parameter can develop on rare spatial regions. This leads to an exponential dependence of the order parameter on the coupling constant. At finite temperatures the static order on the rare regions is destroyed. This restores the phase transition and leads to a double exponential relation between critical temperature and coupling strength. We discuss the behavior based on Lifshitz-tail arguments and illustrate the results by simulations of a model …

Crop Updates - 2003 Oilseeds, Peter Nelson, Graham Walton, Hasan Zaheer, Paul Carmody, J. A. Fortescue, D. W. Turner, Janet Wroth, Wallace Cowling, Anh-Van Pham, R. F. Brennan, Glen Riethmuller, Greg Hamilton, Jo Hawksley, C. M. Zaicou-Kunesch, D. Eksteen, Françoise A. Berlandier, Christiaan Valentine, Owain Edwards, Roger Jones, Brenda Coutts, Lisa Smith, Jenny Hawkes, Ravjit Khangura, Moin Salam, Art J. Diggle, Martin J. Barbetti, Kevin Walden

Crop Updates

This session covers fifteen papers from different authors

ACKNOWLEDGMENTS

VARIETIES

1. Large scale canola varietal evaluation in WA, Peter Nelson, Oilseeds WA

2. Performance of IT and TT canola varieties in the medium and high rainfall agzones of WA 2001-02, Graham Walton, Hasan Zaheer and Paul Carmody, Department of Agriculture

QUALITY

1. Reproductive biology, cotyledon development and oil accumulation in canola, J.A. Fortescue and D.W. Turner, School of Plant Biology, Faculty of Natural and Agricultural Sciences, The University of Western Australia

2. Plant and environmental factors affecting oil concentration in canola – a mini-review, D.W. Turner, School of Plant Biology, …

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Factors Affecting The Concentration And Flux Of Materials In Two Southern Everglades Mangrove Wetlands, Stephen E. Davis Iii, Daniel L. Childers, John W. Day Jr., David T. Rudnick, Fred H. Sklar

FCE LTER Journal Articles

Concentrations and fluxes of C, N, and P were measured in dwarf and fringe mangrove wetlands along the Taylor River, Florida, USA from 1996 to 1998. Data from these studies revealed considerable spatial and temporal variability. Concentrations of C, N, and P in the dwarf wetland showed seasonal trends, while water source was better at explaining concentrations in the fringe wetland. The total and dissolved organic carbon (TOC and DOC), total nitrogen (TN), and total phosphorus (TP) content of both wetlands was higher during the wet season or when water was flowing to the south (Everglades source). Concentrations of nitrate …

Pliocene Summer Sea Surface Temperature Reconstruction Using Silicoflagellates From Southern Ocean Odp Site 1165, Jason M. Whitehead, Steven M. Bohaty

Department of Earth and Atmospheric Sciences: Faculty Publications

In the modern marine environment the silicoflagellate genus Dictyocha is rare, or absent, south of the Antarctic polar front (APF); the genus Distephanus, in contrast, is dominant. In sediments recovered from ODP Site 1165, 1600 km south of the front, however, three intervals where Dictyocha is abundant are interpreted to represent Pliocene warm events. Comparison of our data with Ciesielski and Weaver’s [1974] modern core top silicoflagellate relationship with sea surface temperature (SST) indicates that at Site 1165 mean annual SST was approximately 5C at 3.7 Ma (event I), and approximately 4C at 4.3–4.4 Ma (event II) and 4.55–4.8 …

Temperature And Mold Size Effects On Density Gradients And Mechanical Properties In A Polyurethane Foam System, Dacia J Jackovich

UNLV Retrospective Theses & Dissertations

Rigid polyurethane foams can be used as a thermal or vibration insulator and energy absorption material. They are often molded directly in place, where a smooth, thin skin forms between the mold and the cellular structure of the foam. Density gradients and the skin are shown to have an effect on the mechanical properties of the foam; This work will investigate the effects of processing temperature and mold size on the average density, density gradient, compressive modulus, and compressive strength, for a molded free rise, water blown polyurethane foam system. Four processing temperatures are used during foam fabrication: 25°C, 40°C, …

Identification Of Dynamic Properties Of Materials For The Spent Nuclear Fuel Package At Elevated Temperatures, Sirisha Dusi

UNLV Retrospective Theses & Dissertations

This thesis attempts to experimentally identify the dynamic properties of materials for the spent nuclear fuel package at elevated temperatures. The implementation of the project involves a number of steps. First, candidate materials for the nuclear fuel package and the appropriate testing systems were identified [15]. Second, fixtures for tensile testing at elevated temperatures using two machines, namely MTS and Instron Dynatup testing machines were designed and manufactured to make them compatible with the room temperature fixture. Third, experimental procedures for elevated temperature testing of materials are proposed for the two testing machines. Finally, impact testing for the candidate materials …

Thermal Time: Body Size, Food Quality And The 10c Rule, Eric Charnov, James Gillooly

Biology Faculty & Staff Publications

Developmental rates of ectotherms (y) are often linearly related to temperature (Tc in C) within some biologically relevant range of temperatures as y = (1/S)(Tc - Tb), where Tb is the estimated temperature at zero development, and the thermal constant S is the development time multiplied by the temperature above Tb (i.e. degree days above Tb). Among similar species, it has been widely shown that S and Tb are negatively related across environments, that S is positively related to body size, and that Tb is independent of body size but increases with mean environmental temperature. Here we present a model …

Polyadenylation Regulates The Stability Of Trypanosoma Brucei Mitochondrial Rnas, Christopher M. Ryan, Kevin T. Militello, Laurie K. Read

Biology

Polyadenylation of RNAs plays a critical role in modulating rates of RNA turnover and ultimately in controlling gene expression in all systems examined to date. In mitochondria, the precise mechanisms by which RNAs are degraded, including the role of polyadenylation, are not well understood. Our previous in organello pulse-chase experiments suggest that poly(A) tails stimulate degradation of mRNAs in the mitochondria of the protozoan parasite Trypanosoma brucei (Militello, K. T., and Read, L. K. (2000) Mol. Cell. Biol. 21, 731-742). In this report, we developed an in vitro assay to directly examine the effects of specific 3′-sequences on RNA degradation. …

Preliminary Summary Of Existing Biological Monitoring Data From Capisic Brook In Portland, Me, Susanne Meidel Meidel, Leon Tsomides

Publications

No abstract provided.

Nf03-582 Early Season Extentstion Using Hotcaps, Laurie Hodges

University of Nebraska-Lincoln Extension: Historical Materials

Hotcaps are covers used to protect individual plants from low temperature stress early in the season. There are three common hotcap designs: opaque plastic milk jugs, waxed paper, and plastic water-filled tubes. They are usually used by home gardeners or market gardeners with limited production. Growers with more acres or more extensive production tend to use row covers or high tunnels that protect more than one plant.

This NebFact discusses the study methodology, findings, and conclusions to using hotcaps in the garden.

Cockroach Infestation In Some Hospitals In Trabzon, Turkey, Bi̇lal Kutrup

Turkish Journal of Zoology

The distribution and abundance of cockroaches were investigated in six hospitals in Trabzon. A total of 4756 (692 females, 652 males and 3412 nymphs) cockroaches were caught between 1^{st} October 1999 and 30^{th} January 2000. It was found that three cockroach species were present in hospitals. Of these, Blattella germanica was the predominant species with 98.25%, followed by Blatta orientalis (1.12%) and Periplaneta americana (0.63%). Although the German cockroach, Blattella germanica, was found in all areas of the hospitals, Blatta orientalis and Periplaneta americana were only caught in kitchens. When comparing the population density of German cockroaches in different places …