Physical Sciences and Mathematics Commons^™

De Novo Synthesis And Degradation Of Lx And V Cycle Pigments During Shade And Sun Acclimation In Avocado Leaves, Britta Forster, C. Barry Osmond, Barry J. Pogson

Faculty of Science - Papers (Archive)

The photoprotective role of the universal violaxanthin cycle that interconverts violaxanthin (V), antheraxanthin (A), and zeaxanthin (Z) is well established, but functions of the analogous conversions of lutein-5,6-epoxide (Lx) and lutein (L) in the selectively occurring Lx cycle are still unclear. We investigated carotenoid pools in Lx-rich leaves of avocado (Persea americana) during sun or shade acclimation at different developmental stages. During sun exposure of mature shade leaves, an unusual decrease in L preceded the deepoxidation of Lx to L and of V to A+Z. In addition to deepoxidation, de novo synthesis increased the L and A+Z pools. …

Responses Of Plants In Polar Regions To Uvb Exposure : A Meta-Analysis, K. K. Newsham, Sharon A. Robinson

Faculty of Science - Papers (Archive)

We report a meta-analysis of data from 34 field studies into the effects of UV-B radiation on Arctic and Antarctic bryophytes and angiosperms. The studies measured plant responses to decreases in UV-B radiation under screens, natural fluctuations in UV-B irradiance, or increases in UV-B radiation applied from fluorescent UV lamps. Exposure to UV-B radiation was found to increase the concentrations of UV-B absorbing compounds in leaves or thalli by 7% and 25% (expressed on a mass or area basis, respectively). UV-B exposure also reduced aboveground biomass and plant height by 15% and 10%, respectively, and increased DNA damage by 90%. …

Using Lidar To Assess The Effect Of Fire And Floods On Upland Peat Bogs, Waterfall Gully, Mount Lofty Ranges, South Australia, Javier Leon Patino, Solomon Buckman, Robert P. Bourman, Rowena Morris, Katherine C. Brownlie

Faculty of Science - Papers (Archive)

A flood exceeding the 100 year average recurrence interval in November 2005 led to the failure of an upland peat bog in Waterfall Gully. The area is prone to severe bushfire and flood events and the control dam at the base of First Falls was filled with sediment sourced from Wilson Bog. A resistant quartzite bar at Fourth Falls has formed a natural constriction point against which burnt logs and debris have collected following previous fire events forming a natural dam resulting in sediment/peat accumulation upstream. The failure of the bog was inevitable as the vegetative material in the log-jam …

Nanoelectrodes: Energy Conversion And Storage, Gordon G. Wallace, Jun Chen, Attila J. Mozer, Maria Forsyth, Douglas R. Mcfarlane, Caiyun Wang

Faculty of Science - Papers (Archive)

Nanosized materials are known to take on peculiar properties compared to the bulk material. Their electronic and mechanical properties are known to improve e.g. higher electrical conductivity and greater strength. Their electrochemical redox properties can change dramatically, e.g. in the case of Ag°, the E° value for Ag°→Ag⁺ + e can change by up to half a volt as the particle size decreases. Nanodimensional materials also have an extraordinarily high surface area to volume ratio. All of these properties would bring beneficial effects if they could be retained when the material is assembled into a structure capable of being …

Paradox Between Public Transport And Private Car As A Modal Choice In Policy Formulation, Ahm Mehbub Anwar

SMART Infrastructure Facility - Papers

This paper presents the stance towards modal choice behavior between public transport and private car. To find out the probable solutions, this paper investigated the latent attitudes of the trip makers concerning modal choice between private car and public transport and the advantages and disadvantages of these two modes as a choice. It was also discussed in this paper that the public transport usage can be increased if the service of public transport is designed in a way that accommodates the level of services required by the customers. Even though, several factors, such as individual characteristics and lifestyle, the type …

An Ontology-Based Simulation Model Exploring The Social Contexts Of Psychostimulant Use Among Young Australians, Pascal Perez, Anne Dray, Paul Dietze, David Moore, Rebecca Jenkinson, Christine Siokou, Rachael Green, Susan L. Hudson, Lisa Maher, Gabriele Bammer

SMART Infrastructure Facility - Papers

The principal anthropogenic factors driving reef degradation have been known for years, if not decades. Overfishing, sedimentation and nutrient loads are just some of the key impacts of human activities in and around reef communities. Therefore, the future of reefs does not rely on generating new knowledge, but rather on implementing and integrating the knowledge we already have. This will require creating effective links between researchers, managers and communities to promote mutual learning, negotiation and collaborative action for reef management. Combining agent-based models and role-play games, through a technique known as Companion Modelling (ComMod), creates a dynamic and interactive setting …

Assessing The Impact Of Regulatory Impact Assessments, Mark Harrison

SMART Infrastructure Facility - Papers

No abstract provided.

Cultural Challenges Of A Maturing Bi Implementation, Craig Napier

SMART Infrastructure Facility - Papers

The University of Wollongong's business intelligence technical implementation has matured through cubes, data warehouses, Cognos 8 and TM1. The non-technical challenges have also evolved, revealing new issues and new opportunities. This presentation looks at what the goals are when you have passed the early milestones and at some of the techniques, issues and solutions facing a business intelligence competency centre as it moves to create a pervasive analytic culture.

Ontology-Based Collaborative Inter-Organizational Knowledge Management Network, Nelson K. Y. Leung, Seung Hwan Kang, S. Lau, Joshua P. Fan

Faculty of Informatics - Papers (Archive)

Knowledge management encourages organizations to create and use knowledge continuously to gain competitive advantage. Some knowledge management approaches are industry specific, theoretical and procedure-wise without consideration of system interoperation. The lack of interoperability means heterogeneous systems from different organizations are unable to communicate, cooperate, exchange, and reuse knowledge with one another. Thus a collaborative interorganizational network is necessary. In this paper, we propose the use of ontology for organizations to access and retrieve inter-organizational knowledge in a similar domain. The incorporation of ontology and its mediation methods in the network allows organizations to reuse the interorganizational knowledge to support individual …

Ranking Method For Optimizing Precision/Recall Of Content-Based Image Retrieval, Jun Zhang, Lei Ye

Faculty of Informatics - Papers (Archive)

The ranking method is a key element of content-based image retrieval (CBIR) system, which can affect the final retrieval performance. In the literature, previous ranking methods based on either distance or probability do not explicitly relate to precision and recall, which are normally used to evaluate the performance of CBIR systems. In this paper, a novel ranking method based on relative density is proposed to improve the probability based approach by ranking images in the class. The proposed method can achieve optimal precision and recall. The experiments conducted on a large photographic collection show significant improvements of retrieval performance.

Long-Term Liming Regime Increases Prime Lamb Production On Acid Soils, G Chen, G D. Li, M K. Conyers, B R. Cullis

Faculty of Informatics - Papers (Archive)

Prime lamb live weight response to lime application on pasture was measured in a grazing experiment in the high rainfall zone of the southwestern slopes of New South Wales, Australia. The pastures were limed every 6 years over 15 years. First cross South African Meat Merino lambs were used as test animals. Preand post-grazing pasture dry matter (DM) yield, botanical composition, feed quality and lamb live weight were monitored over 12 weeks in 2007. Results showed that liming significantly increased pastureDMyield of high quality species and improved overall pasture quality due to increased digestibility and metabolic energy content. As a …

Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Gully And Stream Bank Erosion In Three Pastures With Different Management In Southeast Iowa, George N. Zaimes, Richard C. Schultz, Mustafa Tufekcioglu

Journal of the Iowa Academy of Science: JIAS

Gully and stream banks can be major sources of sediment and nutrients to surface waters, both major water quality problems in the United States. Sediment may also carry phosphorus to surface waters, the primary limiting nutrient causing eutrophication. Overgrazing can induce gully and stream bank erosion by reducing vegetation cover that weakens bank soil resistance to stream water flow. This study examines stream and gully bank erosion adjacent to continuous (CP), rotational (RP) and intensive rotational (IP) pastures, grazed by beef cattle in southeast Iowa. Stream and gully bank erosion were measured by: a) surveying the extent of the severely …

Dr. Lois Hattery Tiffany (1924-2009): In Memoriam, Deborah Q. Lewis

Journal of the Iowa Academy of Science: JIAS

Dr. Lois Hartery Tiffany, Distinguished Professor Emerita, Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, Iowa, died on 6 September 2009. Dr. Tiffany was an outstanding mycologist and teacher. Held in high regard by the public as "Iowa's Mushroom Lady" and known by many students, colleagues and friends as "Dr. T.," she was the matriarch of the Botany Department (now the Department of Ecology, Evolution and Organismal Biology) at Iowa State.

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Som Loss And Soil Quality In The Clear Creek, Ia, A. N. Thanos Papanicolaou, Christopher G. Wilson, Ozan Abaci, Mohamed Elhakeem, Mary Skopec

Journal of the Iowa Academy of Science: JIAS

The Clear Creek, IA Experimental Watershed (CCEW), which drains to the Iowa River, experiences severe surface erosion due to a combination of high slopes, erodible soils, and extensive agriculture. Concurrent with soil loss is the removal of Soil Organic Matter (SOM). High values of SOM have been related to soil quality; therefore, excessive SOM loss corresponds to degrading soil health. Soil quality assessments are important tools for evaluating management practices in agricultural systems; however, it is difficult to measure soil quality directly at the watershed scale because it varies with a number of site-specific soil characteristics. The coupling of soil …

Aryl Ethers From Arenediazonium Tetrafluoroborate Salts: From Neat Reactions To Solvent-Mediated Effects, James A. Shriver, Daniel P. Flaherty, Cameron C. Herr

Journal of the Iowa Academy of Science: JIAS

A general procedure for the synthesis of various aryl ethers via the thermal decomposition of benzenediazonium tetrafluoroborate salts is described. Studies performed in neat alcohol at 60°C gave aryl ethers in yields ranging from 0-73%. Upon completion of a series of reactions, the effect of solvent was explored to expand the scope and relevance of this procedure. It was found that even solvents that are traditionally non-nucleophilic gave rise to products including bi-aryls and N-aryl acetamides. The utilization of an ionic liquid, l-butyl-4-methylpyridinium tetrafluoroborate, resulted in yields comparable to reactions performed in neat alcoholic solvents.

Biodegradation Of 17Β-Estradiol, Estrone And Testosterone In Stream Sediments, Paul Bradley, Larry Barber, Francis Chapelle, James Gray, Dana Kolpin, Peter B. Mcmahon

United States Geological Survey: Staff Publications

Biodegradation of 17β-estradiol (E2), estrone (E1), and testosterone (T) was investigated in three wastewater treatment plant (WWTP) affected streams in the United States. Relative differences in the mineralization of [4-¹⁴C] substrates were assessed in oxic microcosms containing saturated sediment or water-only from locations upstream and downstream of the WWTP outfall in each system. Upstream sediment demonstrated significant mineralization of the “A” ring of E2, E1, and T, with biodegradation of T consistently greater than that of E2 and no systematic difference in E2 and E1 biodegradation. “A” ring mineralization also was observed in downstream sediment, with E1 and …

Precise Location Of San Andreas Fault Tremors Near Cholame, California Using Seismometer Clusters: Slip On The Deep Extension Of The Fault?, David R. Shelly, William L. Ellsworth, Trond Ryberg, Christian Haberland, Gary S. Fuis, Janice Murphy, Robert M. Nadeau, Roland Bürgemann

United States Geological Survey: Staff Publications

We examine a 24-hour period of active San Andreas Fault (SAF) tremor and show that this tremor is largely composed of repeated similar events. Utilizing this similarity, we locate the subset of the tremor with waveforms similar to an identified low frequency earthquake (LFE) ‘‘master template,’’ located using P and S wave arrivals to be ~26 km deep. To compensate for low signal-to-noise, we estimate event-pair differential times at ‘‘clusters’’ of nearby stations rather than at single stations. We find that the locations form a near-linear structure in map view, striking parallel to the SAF and near the surface trace. …

A One-Dimensional Heat-Transport Model For Conduit Flow In Karst Aquifers, Andrew J. Long, Patrick C. Gilcrease

United States Geological Survey: Staff Publications

A one-dimensional heat-transport model for conduit flow in karst aquifers is presented as an alternative to two or three-dimensional distributed-parameter models, which are data intensive and require knowledge of conduit locations. This model can be applied for cases where water temperature in a well or spring receives all or part of its water from a phreatic conduit. Heat transport in the conduit is simulated by using a physically-based heat-transport equation that accounts for inflow of diffuse flow from smaller openings and fissures in the surrounding aquifer during periods of low recharge. Additional diffuse flow that is within the zone of …

Interbasin Flow In The Great Basin With Special Reference To The Southern Funeral Mountains And The Source Of Furnace Creek Springs, Death Valley, California, U.S., Wayne R. Belcher, M. S. Bedinger, Jennifer T. Back, Donald S. Sweetkind

United States Geological Survey: Staff Publications

Interbasin flow in the Great Basin has been established by scientific studies during the past century. While not occurring uniformly between all basins, its occurrence is common and is a function of the hydraulic gradient between basins and hydraulic conductivity of the intervening rocks. The Furnace Creek springs in Death Valley, California are an example of large volume springs that are widely accepted as being the discharge points of regional interbasin flow. The flow path has been interpreted historically to be through consolidated Paleozoic carbonate rocks in the southern Funeral Mountains. This work reviews the preponderance of evidence supporting the …

Structured Decision Making As A Conceptual Framework To Identify Thresholds For Conservation And Management, Julien Martin, Michael C. Runge, James D. Nichols, Bruce C. Lubow, William L. Kendall

United States Geological Survey: Staff Publications

Thresholds and their relevance to conservation have become a major topic of discussion in the ecological literature. Unfortunately, in many cases the lack of a clear conceptual framework for thinking about thresholds may have led to confusion in attempts to apply the concept of thresholds to conservation decisions. Here, we advocate a framework for thinking about thresholds in terms of a structured decision making process. The purpose of this framework is to promote a logical and transparent process for making informed decisions for conservation.

Specification of such a framework leads naturally to consideration of definitions and roles of different kinds …

Series That Probably Converge To One, Thomas J. Pfaff, Max Tran

Publications and Research

No abstract provided.

Appropriate Prosodic Variation Is Valued By Users, Rafael Escalante-Ruiz

Open Access Theses & Dissertations

Spoken dialog systems today do not vary the prosody of their utterances, although prosody is known to have many useful expressive functions. In a corpus of memory quizzes, I identified eleven dimensions of prosodic variation, each with its own expressive function. I identified the situations in which each was used, and how to detect these situations from the dialog context and the prosody of the interlocutor's previous utterance. I implemented the resulting response rules and had 21 users interact with two versions of the system. Overall they preferred the version in which the prosodic forms of the acknowledgments were chosen …

Sustainable Development Extension Plan (Sudex): Community Mobilization Through Proactive Participation And Synergistic Alliance To Alliviate Poverty And Achieve Sustainable Self Sufficiency, Stephen Forbes

Open Access Theses & Dissertations

This Dissertation describes a sustainable development extension plan (Sudex Plan) to help communities in developing countries achieve Goal 1 of the United Nation's Millennium Development Goals (MDG). Goal 1 focuses on reducing poverty and hunger by 50% by the year 2015, but all the MDG are interrelated and one can not be achieved without considering the others, and to attain any is an empty accomplishment without ways to ensure that they can be sustained and continuously improved with the means to pass on the information, knowledge and lessons learned from community to community, generation to generation. The Sudex Plan is …

New Algorithms For Optimal Portfolio Selection, Tanja Magoc

Open Access Theses & Dissertations

Over the past four thousand years, numerous techniques have been developed and used to address problems in Finance. These techniques include simple arithmetic calculations and probabilistic methods as well as intelligent systems techniques such as neural networks, genetic algorithms, multi-agent systems, and support vector machines. The techniques have been developed to accurately and quickly collect, validate, analyze, and integrate data that change dynamically.

The particular problem that we address in this Dissertation is the construction of efficient algorithms for the problem of an optimal portfolio selection, that is, algorithms that would accurately and in real time determine the best distribution …

Semi-Automated Frame Transformations Using Fft Analysis On 2-D Images, Francisco Javier Osuna

Open Access Theses & Dissertations

Cassini entered Saturn's orbit on July 1, 2004 beginning a four-year exploration of Saturn. In 2008 the mission was extended, and Cassini continues to collect and transmit images and data collected during its mission. In order to accurately interpret images, it is necessary to know the location and orientation of the camera provided the field of view when the image was collected. While the mission managers provide initial estimates of this orientation, scientific analysis requires better estimates than the initial data provided. Navigation is a process for improving the estimation of the true camera pointing vector as determined by features …

Pdi, Reactive Oxygen Species Stress And Polyphenolic Phytochemicals: Implications For Neurodegenerative Diseases, Rituraj Pal

Open Access Theses & Dissertations

PDI, protein disulfide isomerase, is one of the most versatile proteins and highly expressed in mammalian cells because there is a vast number of proteins that must undergo processing before secretion to their final destinations. PDI has several functions: oxidation of nascent proteins and isomerization of existing disulfide bonds. It also possesses chaperone activity and participates in protein degradation. Because of its structure, PDI can exist in a reduced or oxidized form. In mammalian cells it is mostly reduced due to the high demand of disulfide bond shuffling of secreted proteins within the ER, PDI a, a', and b' posses …

Computational Modeling Studies Of The Structures And Properties Of Organotin(Iv) And Stannyl-Thioether Systems With Comparisons To X-Ray Crystallography, Michelle R. Stem Joseph

Open Access Theses & Dissertations

Controlling the toxic effects of organotin(IV) compounds involves engineering the structure of the molecules to optimize their properties. Molecular engineering, coupled with improved capabilities to generate reliable computational optimization models (COMs), will enable researchers to have greater success at harnessing the highly specific cytotoxicity of organotins. For example, as the thio_n ligand phenyl groups were replaced with Cl atoms, the S-Sn intramolecularity was strengthened, the bond distance decreased, and the stannyl tetrahedral structure was deformed from its triphenyl conformation. With each substitution, conformation deformations lowered the damaging bioactivity levels of thio_n. Bonding various ligands to organotin(IV) compounds …