Differential fitness of Eucalyptus defense phenotypes under altered nutrient and light conditions

Producing defensive chemicals is a cost for a plant. Scientists have hypothesized that there is always a trade-off between investment in chemical defence and plant physiological and developmental growth processes. It has been proposed that plants growing under high resource availability should use their carbon budget for plant growth rather than defence and that when plants are growing under resource-limited environmental conditions plants use their available carbon budget for the differentiation processes such as the production of defensive chemicals, rather than plant growth. Eucalyptus is the dominant genus of trees in Australian forests and their leaves are the main food source for many herbivores including insects and some arboreal marsupials. However, trees from the genus Eucalyptus possess a complex mixture of plant secondary metabolites (PSM), including formylated phloroglucinol compounds such as sideroxylonal, and a range of water-soluble phenolics. These compounds vary qualitatively and quantitatively between species and quantitatively within species. These plants are extensively studied for the great chemical variation they possess. However, few experiments have been conducted to test for the existence of trade-offs between growth and defence in these plants. The defensive chemistry of Eucalyptus species is mainly constitutively determined and phenotypic plasticity across the environmental variation is less well understood. I aimed to find out under which environmental circumstances this proposed trade-off will take place in Eucalyptus and also the nature of such trade-offs, under different conditions of light and nutrient availability. Eucalyptus melliodora and Eucalyptus camaldulensis seeds were grown under three different light conditions and E. melliodora seedlings were grown under two nutrient conditions and changes in growth parameters and sideroxylonal and total phenolic concentrations of seedlings were observed. Plants under different light and nutrient treatments varied greatly in their growth parameters and foliar PSM concentrations as well. Plants that were grown under higher light levels contained more sideroxylonal and more total phenolics than plants under low light conditions. Plants grown under higher nutrient levels possessed higher sideroxylonal but lower total phenolics compared to low nutrient plants. However, no trade-offs were identified between growth parameters and defensive chemical concentrations under any environmental conditions. Contrary to expectations, positive relationships between growth and concentrations of sideroxylonal were identified between and within many environmental treatments

A clinico-pathological study of the prostate gland: with special reference to its response to experimental injury

SECTION I. A Clinico-pathological Study of Prostatic Carcinoma. • SECTION II, A Combined Morbid Anatomical and Histological Study of Unsuspected Prostatic Carcinoma. • SECTION III, The Response of the Prostate Gland to Experimental Injur

DEVELOPMENT OF MICROCHIP ELECTROPHORESIS BASED METHODS TO PROFILE CELLULAR NITROSATIVE STRESS

Nitric oxide (NO) is the main reactive nitrogen species (RNS) produced by immune cells. NO reacts with superoxide to produce peroxynitrite (ONOO-). These two RNS are capable of nitration, nitrosylation and oxidation of intracellular biomolecules that can alter various biochemical processes. To help maintain cellular redox homeostasis in nitrosative and oxidative stress, antioxidant molecules are present in the cells. However, excessive nitrosative stress can alter the balance between antioxidants and prooxidants and therefore it plays an important role in cancer, cardiovascular and neurodegenerative diseases. A method for the simultaneous detection of prooxidants and antioxidants associated with nitrosative stress in biological samples would be beneficial for better understanding of their role in disease states. Therefore, in this dissertation a separation-based approach is described that makes it possible to detect and quantify cellular antioxidants and prooxidants such as NO, ONOO-, glutathione and ascorbic acid. Microchip electrophoresis (ME) was selected as the separation method due to its fast analysis times, compatibility with low sample volumes and potential future application to chemical cytometry. Most prooxidants and antioxidants are electrochemically active and therefore, electrochemical detection was used as the primary detection mode. First, a ME method with in-channel amperometric detection that employed an isolated potentiostat was developed for the detection of NO, ONOO-, and other biologically important molecules associated nitrosative stress. Separation of these species was achieved in less than 35 s, which made it possible to detect prooxidants before they significantly degraded. Following this, two dual electrode configurations were developed and evaluated for better identification of reactive species in standard mixtures and cell lysates using voltammetric characterization. The ME-amperometric method was then used for detection and quantification of NO2- and NO in macrophage cells under native and LPS stimulated conditions. Glutathione, a cellular antioxidant, was also measured in these studies and compared with the prooxidant levels in the cells. For further confirmation of NO production in these cells, ME with laser induced fluorescence detection was used for the determination of NO using diaminofluorofluorescein. This same probe and separation was also used to investigate the heterogeneity of NO production in single cells using a cytometric device in collaboration with the Culbertson group. The main future goal of this project is to monitor macrophage cellular heterogeneity during nitrosative stress using an electrochemical cytometric device

Strong and selective biomimetic receptors for water-soluble guests through cooperative enhancement and molecular imprinting

This dissertation presents two types of synthetic receptors that mimic their biological counterparts in molecular recognition. The first type is cooperatively enhanced receptors (CERs) that utilize intrahost interactions to magnify their guest binding. The enhancement in binding was achieved by eliminating unfavorable repulsion within the host by the guest. The second type is molecularly imprinted nanoparticles (MINPs) that resemble protein receptors in size, water solubility, and template-specific binding sites. Functionalized with benzoxaborole binding groups, the MINPs could be tailored to bind mono- and oligosaccharides in high affinity and selectivity

Fostering independent learning and critical thinking in management higher education using an information literacy framework

Independent learning and critical thinking are perhaps equally blessed and cursed in the academe. As management academics we strive to foster these capabilities in our students, particularly our undergraduates, and we are often frustrated by our lack of success or impact. The thesis of this paper is that information literacy frameworks provide a ‘way in’ to constructing engaging, independent learning journeys as summative and formative assessment tasks. A model for doing this is proposed using the Australian and New Zealand Information Literacy Framework. A case study is then provided of how this approach was applied in an Operations Management subject at The Queensland University of Technology, Australia, in a partnership involving academics and library staff. Far from being merely about library skills, the conclusion of the paper is that information literacy offers a rich platform for fostering independent learning and critical thinking that has for too long been ignored or undervalued

Environmental Overreach: The EU’s Carbon Tax on International Aviation

On November 27, 2012—without the fanfare of a Rose Garden ceremony—President Obama signed into law a bill that forbids United States airlines from participating in the European Union Emissions Trading Scheme (“EU ETS”). Environmental organizations bemoaned the President’s decision after having urged him to veto the bill. Supporters of the law hailed the passage as a win for American sovereignty, preventing an illegitimate and disingenuous environmental tax on U.S. carriers and passengers. This article addresses the aviation industry’s role in global climate change, and offers an in-depth analysis of the EU ETS and the European Commission’s decision to include international aviation in the ETS. It also discusses the legal implications of the EU’s Aviation Directive and the legal challenge before the European Court of Justice. Finally, this article discusses the aforementioned legislation and exposes the pitfalls of the EU’s unilateral action

Identification of key players in networks using multi-objective optimization and its applications

Identification of a set of key players, is of interest in many disciplines such as sociology, politics, finance, economics, etc. Although many algorithms have been proposed to identify a set of key players, each emphasizes a single objective of interest. Consequently, the prevailing deficiency of each of these methods is that, they perform well only when we consider their objective of interest as the only characteristic that the set of key players should have. But in complicated real life applications, we need a set of key players which can perform well with respect to multiple objectives of interest. In this dissertation, a new perspective for key player identification is proposed, based on optimizing multiple objectives of interest. The proposed approach is useful in identifying both key nodes and key edges in networks. Experimental results show that the sets of key players which optimize multiple objectives perform better than the key players identified using existing algorithms, in multiple applications such as eventual influence limitation problem, immunization problem, improving the fault tolerance of the smart grid, etc. We utilize multi-objective optimization algorithms to optimize a set of objectives for a particular application. A large number of solutions are obtained when the number of objectives is high and the objectives are uncorrelated. But decision-makers usually require one or two solutions for their applications. In addition, the computational time required for multi-objective optimization increases with the number of objectives. A novel approach to obtain a subset of the Pareto optimal solutions is proposed and shown to alleviate the aforementioned problems. As the size and the complexity of the networks increase, so does the computational effort needed to compute the network analysis measures. We show that degree centrality based network sampling can be used to reduce the running times without compromising the quality of key nodes obtained

Transformations and analysis of parallel real time programs

The problem of schedulability analysis of a set of real time programs form a NP complete problem. The exponential complexity of analysis is a direct result of the complexity in the real time programs, as a combinatorial explosion takes place when trying to determine access patterns of shared resources. Thus, to transform the original programs to a less complex form, while preserving its timing characteristics, is the only viable solution. By using such transformations to reduce the complexity of real time programs, it is possible to schedulability analyze programs at compile time efficiently, without adding an unnecessary overhead to the compilation time. A set of suitable transformations and run time scheduling algorithms are introduced and implemented in C++. A library of transformations and analysis routines are provided. The library routines can be used to build prototype schedulability analyzers for testing various analysis techniques. These transformations and the scheduling algorithm will be an integral part of the real time compiler for the real time language RTL. The RTL compiler will not only produce fast and efficient code for an arbitrarily specified real time hardware architecture, but also will provide the worst case timing characteristics for the programs

DEVELOPMENT OF BIOINFORMATICS TOOLS AND ALGORITHMS FOR IDENTIFYING PATHWAY REGULATORS, INFERRING GENE REGULATORY RELATIONSHIPS AND VISUALIZING GENE EXPRESSION DATA

In the era of genetics and genomics, the advent of big data is transforming the field of biology into a data-intensive discipline. Novel computational algorithms and software tools are in demand to address the data analysis challenges in this growing field. This dissertation comprises the development of a novel algorithm, web-based data analysis tools, and a data visualization platform. Triple Gene Mutual Interaction (TGMI) algorithm, presented in Chapter 2 is an innovative approach to identify key regulatory transcription factors (TFs) that govern a particular biological pathway or a process through interaction among three genes in a triple gene block, which consists of a pair of pathway genes and a TF. The identification of key TFs controlling a biological pathway or a process allows biologists to understand the complex regulatory mechanisms in living organisms. TF-Miner, presented in Chapter 3, is a high-throughput gene expression data analysis web application that was developed by integrating two highly efficient algorithms; TF-cluster and TF-Finder. TF-Cluster can be used to obtain collaborative TFs that coordinately control a biological pathway or a process using genome-wide expression data. On the other hand, TF-Finder can identify regulatory TFs involved in or associated with a specific biological pathway or a process using Adaptive Sparse Canonical Correlation Analysis (ASCCA). Chapter 4 presents ExactSearch; a suffix tree based motif search algorithm, implemented in a web-based tool. This tool can identify the locations of a set of motif sequences in a set of target promoter sequences. ExactSearch also provides the functionality to search for a set of motif sequences in flanking regions from 50 plant genomes, which we have incorporated into the web tool. Chapter 5 presents STTM JBrowse; a web-based RNA-Seq data visualization system built using the JBrowse open source platform. STTM JBrowse is a unified repository to share/produce visualizations created from large RNA-Seq datasets generated from a variety of model and crop plants in which miRNAs were destroyed using Short Tandem Target Mimic (STTM) Technology