Renewable power for lean desktops in media applications

An integration of solar microgeneration to supply a low-power IT desktop, using the Power over Ethernet standards IEEE 802.3af/at as a low power distribution network avoiding transformer losses from DC generation to mains power AC and back to low-voltage DC and hence maximising efficiency. The resulting design points to applications in media technology where reducing grid power consumption is critical for improving sustainability, or where there are supply constraints, and indicates new directions in how we manage and consume power for IT devices

Prism vergence measurements following adaptation to a base out prism

This study examines the effect of adaptation on the prism vergence range following an induced deviation. Five young adult subjects, with normal binocular functions, underwent fusional verfence testing to base in prisms before and after wearing a 10(Δ) base out Fresnel prism. The Fresnel prism was worn for a period of 2, 5, or 10 min on each of three separate occasions. The base in fusional vergence showed no statistical difference before or after adaptation, for any of the time periods. Also there was no difference in the ranges obtained over the three time periods. It was concluded that, even after a 2 min period of adaptation, fusional vergences return to a similar level as before the horizontal deviation was induced

Eileen Tuff Diaries, 1920-1947

Iowa native whose family settled near Rugby, North Dakota in 1899. Eileen Tuff kept diaries of her life on the farm, spanning from 1920 to 1947. Her diaries give us a detailed description of life on a farm in North Dakota during the first half of the twentieth century. They show how independent the family was, especially in terms of growing their own food

The Effects of Kindling on GABA-mediated Inhibition in the Dentate Gyrus of the Rat

Brief, localized electrical stimulation of the brain can elicit a short electrographic afterdischarge (AD). In the rat, repeated stimulation permanently increases the duration of the AD and can lead to the development of a generalized motor seizure. This process has been labelled "kindling" and has been utilized as a model of epilepsy and neural plasticity. Hypotheses concerning the mechanism of the neural change produced by kindling typically specify either an excitatory enhancement or an inhibitory decrement. Of the inhibitory neurotransmitters that are likely to be involved, Υ-aminobutyric acid (GABA) is probably the least studied. The hypothesis that GABA hypofunction contributes to the establishment of the kindled response was tested by the experiments in this thesis. GABA is known to mediate recurrent inhibition in the dentate gyrus of the hippocampus, a structure ideally suited for electrophysiological investigation. Double pulse stimulation of the perforant path input to the dentate gyrus was used in the following experiments to produce paired pulse depression in that site. This depression effect provided an estimate of GABA-mediated recurrent inhibition. The depression was, for example, enhanced by GABA agonist drugs and attenuated by drugs which block GABA transmission. Paired pulse depression was significantly increased following amygdala kindling and was further enhance to near maximal levels by subsequent kindling in the dentate. These results indicated that kindling increased, rather than reduced, inhibition in the dentate gyrus. In addition, kindling did not increase the rate at which inhibition fails under conditions of excessive activation. Trains of 5 Hz stimulation, applied to the perforant path, caused paired pulse depression to disappear and elicited a brief AD. Following kindling, the latency to AD onset tended to be increased rather than shortened, suggesting an enhanced resistance to inhibitory failure. Finally, receptor binding estimates of the number of GABA and associated benzodiazepine (Bz) receptors were made in several brain regions following kindling. While the number of GABA receptors, as measured by both ³H-GABA and ³H-Muscimol binding, was unaltered by kindling, Bz receptors were significantly increased in kindled amygdala and hippocampus. As the Bz receptor apparently functions to enhance GABA transmission, this finding suggests a possible mechanism for the enhanced inhibition observed in the evoked potential experiments. Taken together, the results indicate that kindling does not produce a decrement in GABA-mediated inhibition in the hippocampus and, in fact, enhances it in an apparently compensatory manner. A possible mechanism for this long-term inhibitory potentiation is suggested to be the up-regulation of the Bz receptor.Doctor of Philosophy (PhD

Shape coexistence at the proton drip-line: First identification of excited states in 180Pb

Excited states in the extremely neutron-deficient nucleus, 180Pb, have been identified for the first time using the JUROGAM II array in conjunction with the RITU recoil separator at the Accelerator Laboratory of the University of Jyvaskyla. This study lies at the limit of what is presently achievable with in-beam spectroscopy, with an estimated cross-section of only 10 nb for the 92Mo(90Zr,2n)180Pb reaction. A continuation of the trend observed in 182Pb and 184Pb is seen, where the prolate minimum continues to rise beyond the N=104 mid-shell with respect to the spherical ground state. Beyond mean-field calculations are in reasonable correspondence with the trends deduced from experiment.Comment: 5 pages, 4 figures, submitted to Phys.Rev.

Mechanisms and Geochemical Models of Core Formation

The formation of the Earth's core is a consequence of planetary accretion and processes in the Earth's interior. The mechanical process of planetary differentiation is likely to occur in large, if not global, magma oceans created by the collisions of planetary embryos. Metal-silicate segregation in magma oceans occurs rapidly and efficiently unlike grain scale percolation according to laboratory experiments and calculations. Geochemical models of the core formation process as planetary accretion proceeds are becoming increasingly realistic. Single stage and continuous core formation models have evolved into multi-stage models that are couple to the output of dynamical models of the giant impact phase of planet formation. The models that are most successful in matching the chemical composition of the Earth's mantle, based on experimentally-derived element partition coefficients, show that the temperature and pressure of metal-silicate equilibration must increase as a function of time and mass accreted and so must the oxygen fugacity of the equilibrating material. The latter can occur if silicon partitions into the core and through the late delivery of oxidized material. Coupled dynamical accretion and multi-stage core formation models predict the evolving mantle and core compositions of all the terrestrial planets simultaneously and also place strong constraints on the bulk compositions and oxidation states of primitive bodies in the protoplanetary disk.Comment: Accepted in Fischer, R., Terasaki, H. (eds), Deep Earth: Physics and Chemistry of the Lower Mantle and Core, AGU Monograp

Geologic history of Martian regolith breccia Northwest Africa 7034: Evidence for hydrothermal activity and lithologic diversity in the Martian crust

The timing and mode of deposition for Martian regolith breccia Northwest Africa (NWA) 7034 were determined by combining petrography, shape analysis, and thermochronology. NWA 7034 is composed of igneous, impact, and brecciated clasts within a thermally annealed submicron matrix of pulverized crustal rocks and devitrified impact/volcanic glass. The brecciated clasts are likely lithified portions of Martian regolith with some evidence of past hydrothermal activity. Represented lithologies are primarily ancient crustal materials with crystallization ages as old as 4.4 Ga. One ancient zircon was hosted by an alkali-rich basalt clast, confirming that alkalic volcanism occurred on Mars very early. NWA 7034 is composed of fragmented particles that do not exhibit evidence of having undergone bed load transport by wind or water. The clast size distribution is similar to terrestrial pyroclastic deposits. We infer that the clasts were deposited by atmospheric rainout subsequent to a pyroclastic eruption(s) and/or impact event(s), although the ancient ages of igneous components favor mobilization by impact(s). Despite ancient components, the breccia has undergone a single pervasive thermal event at 500–800°C, evident by groundmass texture and concordance of ~1.5 Ga dates for bulk rock K-Ar, U-Pb in apatite, and U-Pb in metamict zircons. The 1.5 Ga age is likely a thermal event that coincides with rainout/breccia lithification. We infer that the episodic process of regolith lithification dominated sedimentary processes during the Amazonian Epoch. The absence of pre-Amazonian high-temperature metamorphic events recorded in ancient zircons indicates source domains of static southern highland crust punctuated by episodic impact modification

Nitrate-Dependent Iron Oxidation: A Potential Mars Metabolism

This work considers the hypothetical viability of microbial nitrate-dependent Fe2+ oxidation (NDFO) for supporting simple life in the context of the early Mars environment. This draws on knowledge built up over several decades of remote and in situ observation, as well as recent discoveries that have shaped current understanding of early Mars. Our current understanding is that certain early martian environments fulfill several of the key requirements for microbes with NDFO metabolism. First, abundant Fe2+ has been identified on Mars and provides evidence of an accessible electron donor; evidence of anoxia suggests that abiotic Fe2+ oxidation by molecular oxygen would not have interfered and competed with microbial iron metabolism in these environments. Second, nitrate, which can be used by some iron oxidizing microorganisms as an electron acceptor, has also been confirmed in modern aeolian and ancient sediment deposits on Mars. In addition to redox substrates, reservoirs of both organic and inorganic carbon are available for biosynthesis, and geochemical evidence suggests that lacustrine systems during the hydrologically active Noachian period (4.1–3.7 Ga) match the circumneutral pH requirements of nitrate-dependent iron-oxidizing microorganisms. As well as potentially acting as a primary producer in early martian lakes and fluvial systems, the light-independent nature of NDFO suggests that such microbes could have persisted in sub-surface aquifers long after the desiccation of the surface, provided that adequate carbon and nitrates sources were prevalent. Traces of NDFO microorganisms may be preserved in the rock record by biomineralization and cellular encrustation in zones of high Fe2+ concentrations. These processes could produce morphological biosignatures, preserve distinctive Fe-isotope variation patterns, and enhance preservation of biological organic compounds. Such biosignatures could be detectable by future missions to Mars with appropriate instrumentation

Famous Battles of the Civil War

A set of one hundred collecting cards featuring images from Battle of the American Civil War. The set is enclosed in a sealed package.https://scholarsjunction.msstate.edu/fvw-artifacts/3101/thumbnail.jp

Antecedents and Outcomes of Sports Coaches’ Interpersonal Behaviours: Examining External and Internal Control from a Self-Determination Theory Perspective.

Grounded in Self-Determination Theory, the aim of this thesis was to examine the antecedents and outcomes of internally and externally controlling coach behaviours. Despite the known presence of controlling behaviours within sport, there has been an absence of research on these two controlling dimensions and their co-occurrence within a competitive environment. These limitations were addressed through three separate studies that included athletes and coaches from university sport clubs. Study 1 applied a Person-Centred Approach (PCA) to identify coaches’ perceptions of their combined use of autonomy-supportive, internally, and externally controlling behaviours, and associations with their basic psychological needs, motivation, and pressures within their working environment. Study 2 used a PCA to examine the three coaching behaviours from the athlete’s perspective, exploring their predictive utility for adaptive and maladaptive outcomes. Finally, study 3 investigated the relationships of negative athlete outcomes, with congruent and incongruent coach-athlete dyad perceptions of internally and externally controlling coach behaviours. The emergence of a range of coach behaviour profiles in study 1 and 2 supports the importance of adopting a PCA to explore the distinct controlling dimensions; finding combinations of external control and autonomy-support were associated more positively with outcomes in comparison to the use of internal control. Study 2 and 3 revealed that moderate perceptions of internally and externally controlling coach behaviours were more positively associated with athlete outcomes, in contrast to lower perceptions. Therefore, implying that the different controlling coaching behaviours must always be considered and understood when identifying the most adaptive profile in relation to athlete being coached. Additionally, an initial indication of the need for future research to continue to explore relationships among congruent and incongruent coach-athlete dyad perceptions was supported. Across the three studies, support for the distinctive presence that both internal and external control have within the competitive sport environment was evident