Formation and investigation of nanostructured thin films

Small devices, in the range of nanometers, are playing a major role in today's technology. The field of nanotechnology is concerned with materials and systems whose structures and components exhibit novel and significantly improved physical, chemical and biological properties, phenomena and processes due to their small nanoscale size. Researches more and more are finding that structural features in the range of about 1 to 100 nanometers behave quite differently than isolated molecules (1 nanometer) or bulk materials. For comparison, a 10 nanometer structure is 1000 times smaller than the diameter of a human hair. The virtues of working in the nanodomain are increasingly recognized by the scientific community and discussed in the popular press. The use of such devices is expected to revolutionize our industries and lives. ^ This work mainly focuses on the fabrication, characterization and discovery of new nanostructured thin films. This research consists of the design of a new high-deposition rate nanoparticle machine for depositing nanostructured films from beams of nanoparticles and investigation film's unique optical and physical properties.^ A high-deposition rate nanoparticle machine was designed, built and successfully tested. Different nanostructured thin films were deposited from Copper, Gold, Iron and Zirconium targets with the grain size of between 1 to 20 nm under different conditions. Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), and x-ray diffraction (XRD) confirmed nanoscale grain size structures of deposited films. The optical properties of the nanostructured films deposited from copper, Iron and Zirconium targets were significantly different from optical properties of bulk and thin films. Zr, Cu and Fe films were transparent. Gold films revealed an epitaxial contact with the silicon substrate with interesting crystal structures. ^ The new high-deposition rate nanoparticle machine was able to deposit new nanostructured films with different properties from bulk and thin films reported in the literatures. ^

Ecophysiology and biomechanics of Equisetum giganteum in South America

Equisetum giganteum L., a giant horsetail, is one of the largest living members of an ancient group of non-flowering plants with a history extending back 377 million years. Its hollow upright stems grow to over 5 m in height. Equisetum giganteum occupies a wide range of habitats in southern South America. Colonies of this horsetail occupy large areas of the Atacama river valleys, including those with sufficiently high groundwater salinity to significantly reduce floristic diversity. The purpose of this research was to study the ecophysiological and biomechanical properties that allow E. giganteum to successfully colonize a range of habitats, varying in salinity and exposure. Stem ecophysiological behavior was measured via steady state porometry (stomatal conductance), thermocouple psychrometry (water potential), chlorophyll fluorescence, and ion specific electrodes (xylem fluid solutes). Stem biomechanical properties were measured via a 3-point bending apparatus and cross sectional imaging. Equisetum giganteum stems exhibit mechanical characteristics of semi-self-supporting plants, requiring mutual support or support of other vegetation when they grow tall. The mean elastic moduli (4.3 Chile, 4.0 Argentina) of E. giganteum in South America is by far the largest measured in any living horsetail. Stomatal behavior of E. giganteum is consistent with that of typical C3 vascular plants, although absolute values of maximum late morning stomatal conductance are very low in comparison to typical plants from mesic habitats. The internode stomata exhibit strong light response. However, the environmental sensitivity of stomatal conductance appeared less in young developing stems, possibly due to higher cuticular conductance. Exclusion of sodium (Na) and preferential accumulation of potassium (K) at the root level appears to be the key mechanism of salinity tolerance in E. giganteum. Overall stomatal conductance and chlorophyll fluorescence were little affected by salinity, ranging from very low levels up to half strength seawater. This suggests a high degree of salinity stress tolerance. The capacity of E. giganteum to adapt to a wide variety of environments in southern South America has allowed it to thrive despite tremendous environmental changes during their long tenure on Earth.

Imah on the bimah: Gender and the roles of Latin American Conservative congregational rabinas

The aim of this research is to analyze the impact of gender on the work of Latin American rabinas within Conservative congregations in Latin America. The fact that women’s roles in Latin America and in Judaism have been traditionally linked to nurturing and caring serves as the point of departure for my hypothesis, which is that the role rabinas play within their congregations is also linked to those traits. In this research I utilize a social scientific approach and qualitative methodology, conducting personal interviews with the rabinas. While this work proves that Conservative congregations in Latin America are gendered, my research demonstrates that this gendered division of labor does not have a negative impact on the work of rabinas. On the contrary, by embracing attributes of womanhood and motherhood rabinas become imah (mother) on the bimah (pulpit), educating, caring, and nurturing their congregations in a special and unique way.^

Judging psychology experts: Can judges and attorneys distinguish between clinical and experimental psychologists?

A trial judge serves as gatekeeper in the courtroom to ensure that only reliable expert witness testimony is presented to the jury. Nevertheless, research shows that while judges take seriously their gatekeeper status, legal professionals in general are unable to identify well conducted research and are unable to define falsifiability, error rates, peer review status, and scientific validity (Gatkowski et al., 2001; Kovera & McAuliff, 2000). However, the abilities to identify quality scientific research and define scientific concepts are critical to preventing "junk" science from entering courtrooms. Research thus far has neglected to address that before selecting expert witnesses, judges and attorneys must first evaluate experts' CVs rather than their scientific testimony to determine whether legal standards of admissibility have been met. The quality of expert testimony, therefore, largely depends on the ability to evaluate properly experts' credentials. Theoretical models of decision making suggest that ability/knowledge and motivation are required to process information systematically. Legal professionals (judges and attorneys) were expected to process CVs heuristically when rendering expert witness decisions due to a lack of training in areas of psychology expertise.^ Legal professionals' (N = 150) and undergraduate students' (N = 468) expert witness decisions were examined and compared. Participants were presented with one of two versions of a criminal case calling for the testimony of either a clinical psychology expert or an experimental legal psychology expert. Participants then read one of eight curricula vitae that varied area of expertise (clinical vs. legal psychology), previous expert witness experience (previous experience vs. no previous experience), and scholarly publication record (30 publications vs. no publications) before deciding whether the expert was qualified to testify in the case. Follow-up measures assessed participants' decision making processes.^ Legal professionals were not better than college students at rendering quality psychology expert witness admissibility decisions yet they were significantly more confident in their decisions. Legal professionals rated themselves significantly higher than students in ability, knowledge, and motivation to choose an appropriate psychology expert although their expert witness decisions were equally inadequate. Findings suggest that participants relied on heuristics, such as previous expert witness experience, to render decisions.^

Wage matters & globalization: South Florida's low-wage immigrant plant nursery workers and business protectionism in the age of neoliberalism

Ornamental plant production in the State of Florida is an anomaly with respect to current theories of globalization and particularly their explanation of the employment of low-wage, immigrant labor. Those theories dictate that unskilled jobs that do not need to be performed within highly developed countries are outsourced to where labor is cheaper and more flexible. However, the State of Florida remains an important site of ornamental plant production in the US amidst a global economic environment of outsourcing and transnational corporate expansion. This dissertation relies on 50 semi-structured interviews with insiders of the Florida plant nursery industry, focus groups, and participant observation to explain how US trade, labor, and migration policy-making at local levels are not removed from larger global processes taking place in the world since the 1970s. In Florida, elite market players of the plant nursery industry have been able to resist global trends in free trade, operating instead in a protected market. They have done this by appealing to scientific justifications and through arbitrary implementations of neoliberal ideology that keeps small and middle range business alive, while maintaining a seemingly endless supply of marginalized and exploited low-wage, immigrant workers.^

Commitment language as a predictor of alcohol and marijuana use outcomes among adolescents in school -based group treatment

Despite widespread recognition of the problem of adolescent alcohol and other drug (AOD) abuse, research on its most common treatment modality, group work, is lacking. This research gap is alarming given that outcomes range from positive to potentially iatrogenic. This study sought to identify change mechanisms and/or treatment factors that are observable within group treatment sessions and that may predict AOD use outcomes. This NIH (F31 DA 020233-01A1) study evaluated 108, 10-19 year olds and the 19 school-based treatment groups to which they were previously assigned (R01 AA10246; PI: Wagner). Associations between motivational interviewing (MI) based change talk variables, group leader MI skills, and alcohol and marijuana use outcomes up to 12-months following treatment were evaluated. Treatment session audio recordings and transcripts (1R21AA015679-01; PI: Macgowan) were coded using a new discourse analysis coding scheme for measuring group member change talk (Amrhein, 2003). Therapist MI skills were similarly measured using the Motivational Interviewing Treatment Integrity instrument. Group member responses to commitment predicted group marijuana use at the 1-month follow up. Also, group leader empathy was significantly associated with group commitment for marijuana use at the middle and ending stages of treatment. Both of the above process measures were applied in a group setting for the first time. Building upon MI and social learning theory principles, group commitment and group member responses to commitment are new observable, in-session, process constructs that may predict positive and negative adolescent group treatment outcomes. These constructs, as well as the discourse analysis method and instruments used to measure them, raise many possibilities for future group work process research and practice.

Ecophysiology and Biomechanics of Equisetum Giganteum in South America

Equisetum giganteum L., a giant horsetail, is one of the largest living members of an ancient group of non-flowering plants with a history extending back 377 million years. Its hollow upright stems grow to over 5 m in height. Equisetum giganteum occupies a wide range of habitats in southern South America. Colonies of this horsetail occupy large areas of the Atacama river valleys, including those with sufficiently high groundwater salinity to significantly reduce floristic diversity. The purpose of this research was to study the ecophysiological and biomechanical properties that allow E. giganteum to successfully colonize a range of habitats, varying in salinity and exposure. Stem ecophysiological behavior was measured via steady state porometry (stomatal conductance), thermocouple psychrometry (water potential), chlorophyll fluorescence, and ion specific electrodes (xylem fluid solutes). Stem biomechanical properties were measured via a 3-point bending apparatus and cross sectional imaging. Equisetum giganteum stems exhibit mechanical characteristics of semi-self-supporting plants, requiring mutual support or support of other vegetation when they grow tall. The mean elastic moduli (4.3 Chile, 4.0 Argentina) of E. giganteum in South America is by far the largest measured in any living horsetail. Stomatal behavior of E. giganteum is consistent with that of typical C3 vascular plants, although absolute values of maximum late morning stomatal conductance are very low in comparison to typical plants from mesic habitats. The internode stomata exhibit strong light response. However, the environmental sensitivity of stomatal conductance appeared less in young developing stems, possibly due to higher cuticular conductance. Exclusion of sodium (Na) and preferential accumulation of potassium (K) at the root level appears to be the key mechanism of salinity tolerance in E. giganteum. Overall stomatal conductance and chlorophyll fluorescence were little affected by salinity, ranging from very low levels up to half strength seawater. This suggests a high degree of salinity stress tolerance. The capacity of E. giganteum to adapt to a wide variety of environments in southern South America has allowed it to thrive despite tremendous environmental changes during their long tenure on Earth.

Wage Matters & Globalization: South Florida’s Low-Wage Immigrant Plant Nursery Workers and Business Protectionism in the Age of Neoliberalism

Ornamental plant production in the State of Florida is an anomaly with respect to current theories of globalization and particularly their explanation of the employment of low-wage, immigrant labor. Those theories dictate that unskilled jobs that do not need to be performed within highly developed countries are outsourced to where labor is cheaper and more flexible. However, the State of Florida remains an important site of ornamental plant production in the US amidst a global economic environment of outsourcing and transnational corporate expansion. This dissertation relies on 50 semi-structured interviews with insiders of the Florida plant nursery industry, focus groups, and participant observation to explain how US trade, labor, and migration policy-making at local levels are not removed from larger global processes taking place in the world since the 1970s. In Florida, elite market players of the plant nursery industry have been able to resist global trends in free trade, operating instead in a protected market. They have done this by appealing to scientific justifications and through arbitrary implementations of neoliberal ideology that keeps small and middle range business alive, while maintaining a seemingly endless supply of marginalized and exploited low-wage, immigrant workers.