Chiral Modification of the Tetrakis(pentafluorophenyl)borate Anion with Myrtanyl Groups

The synthesis and characterization of chiral [B(C6F5)4]– derivatives bearing a myrtanyl group instead of a fluoro substituent in the para position are described. These new chiral borates were isolated as their bench‐stable lithium, sodium, and cesium salts. The corresponding trityl salts were prepared and tested as catalysts in representative counteranion‐directed Diels–Alder reactions and Mukaiyama aldol additions but no enantioselectivity was obtained. Preformation of a chalcone‐derived silylcarboxonium ion with the chiral borate as counteranion did not lead to any asymmetric induction in a reaction with cyclohexa‐1,3‐diene.TU Berlin, Open-Access-Mittel - 201

Lone Female Headship and Welfare Policy in Canada

The principal qualifying condition for welfare in Canada, unlike the US, is financial need - there are no demographic criteria. We use a time-series of annual, national cross-sections for the period 1981 through 1993 to estimate a model of lone-female headship. Our findings do not support the hypothesis that welfare benefit levels for one-parent and two-parent families are important determinants of the likelihood that a Canadian woman is a lone mother. In all models with provincial fixed effects, the coefficients for welfare benefits are small, statistically insignificant and often of the unexpected sign. We do find that the probability that a woman is a lone mother is generally associated in the expected fashion with her earnings capacity and the earnings capacity of her potential male partner, and with her age and schooling.

Acceleration Methodology for the Implementation of Scientific Applications on Reconfigurable Hardware

The role of heterogeneous multi-core architectures in the industrial and scientific computing community is expanding. For researchers to increase the performance of complex applications, a multifaceted approach is needed to utilize emerging reconfigurable computing (RC) architectures. First, the method for accelerating applications must provide flexible solutions for fully utilizing key architecture traits across platforms. Secondly, the approach needs to be readily accessible to application scientists. A recent trend toward emerging disruptive architectures is an important signal that fundamental limitations in traditional high performance computing (HPC) are limiting break through research. To respond to these challenges, scientists are under pressure to identify new programming methodologies and elements in platform architectures that will translate into enhanced program efficacy. Reconfigurable computing (RC) allows the implementation of almost any computer architecture trait, but identifying which traits work best for numerous scientific problem domains is difficult. However, by leveraging the existing underlying framework available in field programmable gate arrays (FPGAs), it is possible to build a method for utilizing RC traits for accelerating scientific applications. By contrasting both hardware and software changes, RC platforms afford developers the ability to examine various architecture characteristics to find those best suited for production-level scientific applications. The flexibility afforded by FPGAs allow these characteristics to then be extrapolated to heterogeneous, multi-core and general-purpose computing on graphics processing units (GP-GPU) HPC platforms. Additionally by coupling high-level languages (HLL) with reconfigurable hardware, relevance to a wider industrial and scientific population is achieved. To provide these advancements to the scientific community we examine the acceleration of a scientific application on a RC platform. By leveraging the flexibility provided by FPGAs we develop a methodology that removes computational loads from host systems and internalizes portions of communication with the aim of reducing fiscal costs through the reduction of physical compute nodes required to achieve the same runtime performance. Using this methodology an improvement in application performance is shown to be possible without requiring hand implementation of HLL code in a hardware description language (HDL) A review of recent literature demonstrates the challenge of developing a platform-independent flexible solution that allows access to cutting edge RC hardware for application scientists. To address this challenge we propose a structured methodology that begins with examination of the application\u27s profile, computations, and communications and utilizes tools to assist the developer in making partitioning and optimization decisions. Through experimental results, we will analyze the computational requirements, describe the simulated and actual accelerated application implementation, and finally describe problems encountered during development. Using this proposed method, a 3x speedup is possible over the entire accelerated target application. Lastly we discuss possible future work including further potential optimizations of the application to improve this process and project the anticipated benefits

Penn State Extension Services and Plain People: An Inside Perspective on a Trust-based Relationship

This perspective on Penn State Extension Services and plain people is based on my personal experiences as a plain person, in which I interacted with Extension Services first as a farmer, and then (while working on a doctorate) as a part of the Extension system. Penn State Extension started over a century ago and was deliberate in reaching out to plain (conservative Anabaptist) farmers since the beginning, which led to a history of trust-based cooperation. For all these successes there remain challenges to effective cooperation with certain plain individuals and subgroups. I suggest these challenges are broadly similar to those experienced in other cross-cultural interactions, such as those that span broader cultural divides within the United States, and I discuss them within the categories of personal and social, technological, and philosophical differences. In general these differences are less problematic in typical Extension work that is well-defined in scope, such as management of specific insects or diseases, while successful cooperation on more open-ended topics, such as food safety, agricultural runoff, and (especially in the early years) the Extension System itself, relies heavily on trust-based personal relationships that arise from commonalities and mutual understandings that extend beyond the subject matter. More broadly, building on the history of trust-based cooperation, I present a vision of farmers (both plain and non-plain) and the scientific community as collaborators in the production of nutritious and affordable food, with Extension personnel as key communicators in that farming-science interface. [Abstract by author.

Structural studies of titanyl and zirconyl sulphate hydrates

The aim of this thesis was to use a combination of computer simulations and experimental methods to gain insight into the unknown structure of the material titanyl sulphate dihydrate, TiOSO4*2H2O.Samples of TiOSO4*2H2O, along with TiOSO4*H2O, were produced and analysed using X-ray and neutron diffraction at both laboratory and synchrotron facilities. Both ex-situ and in-situ experiments were performed in order to analyse both the structure and growth of the crystals. The diffraction data resulting from these experiments was then used in various structure determination programs. A unit cell was able to be determined from the synchrotron X-ray diffraction patterns, and the first neutron diffraction pattern of a TiOSO4*2D2O sample was produced. In-situ synchrotron X-ray diffraction studies showed that the formation of the crystals followed a single step process, and indicated the possibility of meta-stable phases being present in the sample.In parallel with the experimental studies, computer modelling was used to develop and create candidate TiOSO4*2H2O structures. Initially both forcefield and first principles techniques were validated against a series of test cases. These included the first such calculations for the TiOSO4 and TiOSO4*H2O structures. The candidate structures of TiOSO4*2H2O thus produced were then used as input into the structural determination step.Structure determination was attempted with multiple approaches, using the determined unit cell and a variety of space group settings. Despite a thorough treatment and validation of the method using the diffraction data and known structure of TiOSO4*H2O, the structure was unable to be solved. However, structural motifs consistent with a layered, needle-like morphology, as observed in experimental studies, were commonly found to be present in solutions offered by these approaches. Future use of techniques such as the substitution of isotopic titanium in neutron diffraction may provide enough information to more accurately determine atomic positions

Inattention, Learning Incentives, and Future Returns

I implement an empirical measure of investors’ ex-ante learning incentives based on the theoretical learning index described in Van Nieuwerburgh and Veldkamp’s (2009) rational inattention theory of investors’ learning decisions, which I call the average learning incentive (ALI). I validate ALI by testing three predictions made about it in NV (2009): that it is negatively associated with future returns; positively associated with analyst coverage; and associated with home bias in a quadratic, inverted-U shape. I find support for each prediction. Drawing on accounting theory regarding the cost of capital, I then move beyond the predictions in NV (2009) and test the association between ALI and future factor-adjusted returns in a series of subsamples, and find that while ALI is generally negatively associated with future returns, the reverse relation holds for firms with imperfect equity markets and poor information environments. I also find that the well-established negative association between accrual quality and future returns is mediated by investor learning incentives, and that it only appears when ALI is low, indicating that investors can disentangle poor quality reporting when their motivation to do so is high.Doctor of Philosoph

A review of knowledge of the potential impacts of GMOs on organic agriculture

The organic movement believes that organic agriculture, by its nature, cannot involve the use of genetically modified organisms (GMOs). This has been incorporated into EU regulations which state that there is no place in organic agriculture for GMOs. The aim in this review is to consider the ways in which the use of GMOs in agriculture in the UK and internationally might impact on organic farming. It does not address the controversy about the rights or wrongs of GMO’s per se. The subjects covered are based on a set of questions raised at the beginning of the study. The review is based primarily on evidence from peer-reviewed literature. The report is based on a number of themes, as follows: • Fate of DNA in soil • Fate of DNA in livestock feed and possible impact of GM feed • Fate of DNA in slurry, manure, compost and mulch • Impact of herbicide tolerant crops • Impact of pest and disease resistant crops • Safety of promoters • DNA transfer in pollen and seeds • Horizontal gene transfer • Impact of scale The report’s Executive Summary includes summaries of the findings on each of these themes

Comparison between RF and electrical signals from the partial discharge activity of twisted pair cables at reduced pressures

A pressure-controlled test facility has been set up that allows the PD behaviour of polymer insulated twisted pair samples exposed to 50 Hz AC voltages in the range of 0 to 10 kV to be characterised. Resulting PD activity is quantified using the methods defined in IEC standard 60270 and by using a simple monopole antenna to detect the RF signals excited inside the pressure vessel by the discharges. This paper gives the results of preliminary tests performed on samples of wire insulated with Ethylenetetraflourethylene, Silicon Rubber and Polyvinylchloride in the pressure range between 103 and 105 Pa in atmospheric air. The dependence of PD inception voltage on the environmental pressure is reported. Changes in the behaviour of the PD activity; the correlations between the RF and electrical measurements and the frequency components of the RF signals as the applied voltage and pressure are varied are characterised and discussed