A variety of nanostructures of tin (IV) oxide (TO) are synthesized using two fabrication methods: a solution spin-coating method followed by post-annealing in an oxygen flow and a newly developed catalyst-assisted pulsed laser deposition (PLD) technique. The spin-coating method is used to fabricate granular TO films with monodisperse, stable, ultra-small nanocrystallites (4-5 nm in size), the size of which is found to increase exponentially with post-anneal above 500??C. These nanocrystalline films are conductive and highly transparent, and their bandgap shows broadening due to a high carrier concentration. Their resistivity behavior as a function of temperature in the 50-280 K range can be explained by a two-medium transport model, i.e. transport through the crystalline grains and across the grain boundaries, and through the charge-depletion layer, where a potential barrier is found for transport across the grain boundaries. Electronic transport in these films follows a 3D-variable range hopping model, which reveals an increase in the localization length of carriers with increasing the TAnneal above the onset of exponential growth at TAnneal= 500??C. By homogenously doping Eu3+ in these nanocrystalline films up to a high doping level of ~ 8%, optical luminescence and magnetic orderings can be introduced into these nanocrystalline TO films. Both characteristic Eu3+ emission and defect-related TO emissions are observed in the otherwise transparent TO films upon UV-excitation. In spite of the non-magnetic nature of Eu3+ ions, magnetic orderings appear in the highly doped TO films below 50 K upon the emergence of Eu2Sn2O7 phase. In the second part of this work, we employ a layer of gold nanoislands with controlled sizes (10-50 nm) as catalysts for pulsed laser deposition of TO nanostructures. Highly crystalline TO nanobricks, cuboid nanoparticles, nanowires and nanobelts are obtained for the first time through vapour-solid or vapour-liquid-solid (VLS) mechanisms. Of particular interest are the micron long one-dimensional (1D) nanowires and nanobelts, with the smallest square and rectangular cross-sections, respectively, ever reported. These single-crystalline nanostructures are obtained at relatively low temperatures of 600??C, for nanowires, and 500??C, for nanobelts, and their cross-sectional sizes can be easily controlled by the size of the gold nanoislands. The nanobelts are found to grow along the [100] and [101] axes, while the nanowires appear to grow along the [100] axis. The growth evolution of the nanobelts are also investigated in detail revealing their VLS growth mode and their single-crystalline structure throughout the growth, which opens the prospect of controlling their growth axis and consequently their side-surface planes by pinning the base to the substrate at the desired crystalline orientation. Together, the two fabrication methods developed in the present work offer facile approaches to growing two scientifically and technologically important classes of TO nanostructures, i.e., nanocrystalline film and 1D nanostructures. Thorough characterization of the resulted nanostructured materials using advanced microscopic, spectroscopic and other techniques, including Helium Ion Microscopy, has been provided. Modification of structure, morphology and physical properties of these functional nanostructured materials are also illustrated by controlling the growth parameters and by (Eu-)doping, which pave the way for introducing new properties for applications in chemical sensing, (opto)electronics and displays.

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Taking into account the expected increase in global energy demands and increasing climate change issues, there is a pressing need to develop new environmentally sustainable energy systems. Nuclear energy will play a major role in being part of the energy mix since it offers a relatively clean, safe and reliable source of electrical energy. However, opportunities for building new generation nuclear systems will depend on their economic and safety attractiveness as well as their flexibility in design to adapt in different countries and situations. Keeping these objectives in mind, a framework for international cooperation was set forth in a charter of Generation IV International Forum (GIF) (GIF Charter, 2002) and six design concepts were selected for further development. To achieve high thermal efficiencies of up to 45 ??? 50%, the use of SuperCritical Fluids (SCFs) as working fluids in heat transfer cycles is proposed Generation IV designs. An important aspect towards development of SCF applications in novel Gen IV Nuclear Power Plant (NPP) designs is to understand the thermodynamic behavior and prediction of Heat Transfer Coefficients (HTCs) at supercritical (SC) conditions. In addition to the nuclear power industry applications; SCFs are also expected to play a vital role in a number of other important technologies such as refrigeration systems, and geothermal systems, to name a few. Given the potential for vast number of applications of SCFs in industry, the objective of this work was to gain an understanding on the behavior of SCFs and to develop a fundamental knowledge of the heat-transfer processes and correlations for SC Water and SC CO2 flowing in bare circular tubes. Experimental datasets for SC Water and SC CO2 were compiled and used to obtain a basic 1-D empirical correlation that can predict HTC in bare circular tubes during the transient phases. The accuracy of these correlations was also analyzed using statistical techniques. Limitations and applications for 1-D correlations are discussed as well. The new correlations showed promising results for HTC and Tw calculations for the reference dataset with uncertainty of about ??25% for HTC values and about ??10-15% for the calculated wall temperature.

Objective. This thesis examines the extent to which an intelligence test, the Reynolds Intellectual Assessment Scales (RIAS), aligned with the Carroll-Horn-Cattell theory of intelligence in children ages 4-18 who are either typically-developing or who have a variety of clinical impairments. Other aspects of the RIAS’s construct validity were also evaluated, including its relationship with the Wechsler Intelligence Scales for Children – Fourth Edition (WISC-IV) and whether the RIAS measures intelligence in the same way in typically-developing children as in children with traumatic brain injury (TBI). Methods. Confirmatory factor analysis was used to evaluate the fit of one-factor (g) and two-factor (Verbal Ability and Non-Verbal ability) models in each sample. Configural and measurement invariance of each model were evaluated across the typically-developing group and a group of children with TBI. Correlations between scores on the RIAS and WISC-IV were examined in a group of children with clinical disorders. Results. The two-factor model fit the data of both groups while the one-factor model provided good fit to only the typically-developing group`s data. Both models showed configural invariance across groups, measurement invariance of the two-factor model, and partial measurement invariance of the one-factor model (What`s Missing subtest unconstrained), but scalar invariance was not established for either model. RIAS’s verbal subtests and indexes correlated with theoretically consistent WISC-IV indexes but the RIAS’s nonverbal subtests and indexes did not correlate highly with WISC-IV performance subtests. All RIAS index scores were higher than WISC-IV index scores. Conclusions. Evidence for the interpretability of the NIX and VIX as separate indexes was not found. The VIX is a valid index of crystallized abilities but the NIX does not adequately measure fluid intelligence. The CIX appears to provide a valid measure of g, but may be overly reliant on verbal abilities. The RIAS has significant validity issues that should limit its use in making important decisions. / Graduate

This study investigates the effects that commercial computer games have on young individuals social comfort and learning progress. As a systematic study of literature, scholarly articles have been analysed in order to illuminate the positive as well as negative effects on social comfort and learning progress that may come with playing computer games. The social effects have mainly been discussed with role-playing games, such as World of Warcraft, as starting point, while the learning effects have been coupled with strategy games, such as Civilization IV. The study does not simply declare how these games can be good for these factors, but also in what respect computer games may prevent the development of young individuals socials skills and learning progress. The study showed that in spite of perpetual prejudices against computer games in the technological age, computer games might actually be good to use as a tool in order to authorize the development of young individuals regarding learning and social aspects. However, computer games may as well become the source of problems regarding time, family and school results.

Plant breeding and the development of new or better varieties of plants are essential parts of modern agronomy, horticulture and forestry. The basis for such improvement is a knowledge of the factors and principles of genetics. A number of genetic studies have been made with barley in recent years. This is partly because of the many distinct heritable characters of barley plants. The cultivated species of barley offers the plant breeder and geneticist a wealth of material for genetic studies. Varieties differ in a great many readily distinguishable characters, species hybridize readily, and their small number of chromosomes make it good material for inheritance studies. The barley genetic work has been divided among the principal workers in the U.S., each being responsible for one linkage group. This station has been assigned group IV of which this study is a part. A study of the inheritance of other genes not located in linkage group IV, but appearing in the crosses used, has also been made. This investigation is a by-product of the cereal breeding and improvement program being carried on the Utah Agricultural Experiment Station.

Rectification phenomena in two specific mesoscopic systems are reviewed. The phenomenon is called ratchet effect, and such systems are called ratchets. In this thesis, particularly a rocked quantum-dot ratchet, and a tunneling ratchet are considered. The origin of the name is explained in a brief historical background. Due to rectification, there is a net non-vanishing electronic current, whose direction can be reversed by changing rocking amplitude, the Fermi energy, or applying magnetic field to the devices (for the rocked ratchet), and tuning the temperature (for the tunneling ratchet). In the last part, a theoretical examination based on the Landauer-B&uuml / ttiker formalism of mesoscopic quantum transport is presented.

Catalysts play a vital role in almost every aspect of our lives and are used in the production of fuels, polymers, chemicals, foods, and pharmaceuticals. One challenge facing the heterogeneous catalysis community is the targeted synthesis of dispersed catalyst ensembles. The Barnes research group has developed a general methodology for the synthesis of nanostructured silicate building block supports and heterogeneous catalysts. This methodology provides researchers with the ability to control the dispersion of surface functionality, the dispersion of metal cation centers, the number of linkages from the metal cation center to the support, the surface area of the support, and the porosity of the support. This dissertation describes work aimed at synthesizing and characterizing nanostructured silicate building block supports and heterogeneous catalysts. Nanostructured silicate building block supports were synthesized by reacting SiCl4py2 with Si8O12(OSnMe3)8. The resulting supports contained spatially isolated Me3Sn groups and the density of Me3Sn groups was targeted by varying the stoichiometric ratio of reactants. The stoichiometric ratio of reactants also controlled the surface area and porosity of the supports. Nanostructured heterogeneous catalysts with isolated tungsten(VI) or zirconium(IV) centers were synthesized by reacting a limiting amount of a metal chloride with either Si8O12(OSnMe3)8 or a premade silicate building block support. Two types of catalysts ensembles were targeted: embedded and surface. Embedded ensembles were successfully targeted using WOCl4 and ZrCl4 while the reaction between WCl6 and the building block did not result in the preparation of the targeted ensemble. However the resulting ensemble was thoroughly characterized even though the targeted ensemble was not produced. In all three cases a single type of catalyst ensembles was synthesized and a high surface area silicate support was generated around the embedded ensembles without disrupting the ensemble itself. Surface ensembles were successfully targeted using ZrCl4. The reaction between the tungsten chlorides (WOCl4 and WCl6) and the premade support did not result in the preparation of the targeted ensembles however the resulting ensembles were thoroughly characterized.

Mental illness is common, and usually starts early in life. However, the majority of those affected never seek mental health care. The overall aim of this thesis was to increase knowledge about help-seeking young adults with mental illness in order to improve diagnostic procedures in clinical psychiatry. A group of young adult psychiatric out-patients (n=217) were consecutively invited to participate in the study between October 2002 and September 2003. Altogether 200 (92%) agreed to participate. Among them, there were 161 (80%) women and 39 (20%) men. Participants’ mean age was 22.4±1.9 years. All participants were carefully and comprehensively assessed with respect to axes I, II, IV and V in the DSM-IV. Psychiatric disorders and personality disorders were assessed using the Structured Clinical Interview for DSM-IV for axis I disorders and the Structured Clinical Interview for DSM-IV for axis II disorders. Psychosocial and environmental problems (axis IV) were evaluated through structured interviewing by a social worker and by self-assessment with a questionnaire. Professional and patient ratings on the Global Assessment of Functioning scale were compared before and after treatment. Patients also reported on the Swedish universities Scales of Personality, the Child and Adolescent Psychiatric Screening Inventory-Retrospect and the Coddington’s life event scale. Taken together, the young adult, psychiatric outpatients were characterized by an early onset of their mental disorders, by co-morbidity, by being female and by having mood or anxiety disorders. There were no significant differences between self-referred and those referred by medical professionals according to either number of current or lifetime diagnoses. Childhood onset of depression was associated with more severe symptoms, more psychosocial risk factors, and more childhood developmental delays. Axis IV psychosocial stress categories were related to the presence of axis I disorders, personality disorders, co-morbidity, and impaired functioning. Agreement between patients’ and professionals’ ratings on the GAF scale was good before treatment and excellent after treatment. In summary, the findings suggest that direct self-referral to specialized psychiatric care does not seem to be associated with overutilization of such care. Childhood onset of depression is associated with a more complex illness. The revised axis IV according to DSM-IV seems to have concurrent validity, but is still hampered by limited reliability. And finally, the results support the usefulness of the self-report GAF instrument for measuring outcome in psychiatric care.

Antibiotic-resistant bacteria are increasingly a major healthcare problem but very few new classes of antibiotics have been discovered or launched in recent decades. Approaches to dealing with the problem include learning how bacteria evolve to resistance and improving dosing regimens with current antibiotics so as to reduce the selection of resistant bacteria. This thesis presents studies examining whether antibiotic dosing at high levels can prevent the selection of fluoroquinolone-resistant mutants in Escherichia coli. It also addresses the genetics of fluoroquinolone resistance in E. coli in relation to fitness costs for the resistant bacteria, and the evolution of E. coli to reduce the costs of resistance. The mutant prevention concentration (MPC) of ciprofloxacin was measured for a set of clinical urinary tract infection E. coli strains showing that MPC could not be predicted from the minimum inhibitory concentration (MIC). Results from an in vitro kinetic model showed that an AUC/MPC >22 for ciprofloxacin was the single best pharmacodynamic index that predicted prevention of resistance emergence in the wild-type. Simulating currently approved dosing regimens for three different fluoroquinolones it was found that only a few were effective in preventing the selection of a small sub-population of pre-existing mutants. Step-wise selection of fluoroquinolone resistance showed that the accumulation of mutations usually reduced bacterial fitness in vitro and in vivo. Systematic construction of isogenic resistant strains confirmed this result and revealed that some combinations of resistance mutations mutually compensate and increase both resistance and fitness. It was discovered that mutations altering RNA polymerase could ameliorate the fitness costs of fluoroquinolone resistance. Thus, the major fitness cost of fluoroquinolone resistance is due to defective transcription. The finding that fluoroquinolone resistance mutations can increase resistance while mutually compensating their fitness costs, shows that resistance to fluoroquinolones can continue to evolve in the absence of antibiotic selection.