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2004

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Articles 2431 - 2460 of 2687

Full-Text Articles in Life Sciences

The Effects Of Lawn Management On Soil Microarthropods, Loren B. Byrne, Mary Anne Bruns Jan 2004

The Effects Of Lawn Management On Soil Microarthropods, Loren B. Byrne, Mary Anne Bruns

Arts & Sciences Faculty Publications

No abstract provided.


Scale Model Of A Soil Aggregate And Associated Organisms: A Teaching Tool For Soil Ecology, Mary Anne Bruns, Loren B. Byrne Jan 2004

Scale Model Of A Soil Aggregate And Associated Organisms: A Teaching Tool For Soil Ecology, Mary Anne Bruns, Loren B. Byrne

Arts & Sciences Faculty Publications

Soil is a complex habitat for diverse biota. A significant challenge in teaching soil ecology is our inability to observe organisms as they live and interact in the soil. The objective of this article is to describe an interactive class project to help students visualize the sizes of different groups of soil organisms and to relate these to soil structural components. This project was carried out by students in an upper-level undergraduate soil ecology class. It involved the design and construction of a 4000× scale model of a soil aggregate and its associated organisms. The body of the model was …


Testing For Resistance Of Pelagic Marine Copepods To A Toxic Dinoflagellate, Sean Colin, Hans G. Dam Jan 2004

Testing For Resistance Of Pelagic Marine Copepods To A Toxic Dinoflagellate, Sean Colin, Hans G. Dam

Arts & Sciences Faculty Publications

With few exceptions, the evolutionary consequences of harmful algae to grazers in aquatic systems remain unexplored. To examine both the ecological and evolutionary consequences of harmful algae on marine zooplankton, we used a two-fold approach. In the first approach, we examined the life history responses of two geographically separate Acartia hudsonica (Copepoda Calanoida) populations reared on diets containing the toxic dinoflagellate Alexandrium fundyense . One copepod population was from a region, Casco Bay, Maine, USA, that has experienced recurrent blooms of highly toxic Alexandrium spp. for decades; whereas the other population from Great Bay, New Jersey, USA, has never been …


Safety Performance On 20 Construction Sites In Dublin, Paul Mcevoy Jan 2004

Safety Performance On 20 Construction Sites In Dublin, Paul Mcevoy

Masters

Abstract The aim of this research was to assess factors affecting safety performance on twenty apartment construction sites in Dublin using qualitative and quantitative risk assessment techniques. The quantitative techniques involved observing compliance with recommended safety procedures. The qualitative techniques involved an assessment of site safety management documentation and semi structured interviews with site management regarding site safety procedures. The field work was carried out between November 2003 and October 2004. The results showed that five sites out of twenty had high standards of safety and prevented all possible falls from heights. The five best performing sites were characterised by …


An Examination Of Psychological Variables Affecting Injured Athletes Prior To Returning To Play, Jessica Marie Meyers Jan 2004

An Examination Of Psychological Variables Affecting Injured Athletes Prior To Returning To Play, Jessica Marie Meyers

College of Graduate Studies: Theses & Dissertations (1964–2006)

Injury occurs in a variety of different sports and affects athletes in a number of different ways. Following injury, athletic identity is often lost, bringing upon feelings of anger and depression (Brewer, 1993; Fortunato & Marchant, 1999). As athletes begin to re-enter sports, lower levels of sport-confidence are exhibited (Johnston & Carroll, 1998). Social support has been shown to motivate individuals as well as aid in the overall progress of rehabilitation (Ford & Gordon, 1999; Magyar & Duda, 2000). The purpose of the current study was to determine psychological factors that may influence returning to a sport in which injury …


Concentration Characteristics And Batting Performance In Collegiate Baseball And Softball, Daniel Samess Jan 2004

Concentration Characteristics And Batting Performance In Collegiate Baseball And Softball, Daniel Samess

College of Graduate Studies: Theses & Dissertations (1964–2006)

This study examined relationships between batting performance, trait anxiety, and concentration style. A predictive analysis was also formed to determine the combination of subscales that may best explain variance in batting performance. To accurately measure these variables, the Sport Competition Anxiety Test (SCAT; Martens, Vealey, & Burton, 1990) and the Batting-specific Test of Attentional and Interpersonal Style (B-TAIS; Albrecht & Feltz, 1987) were employed. Participants consisted of both male collegiate baseball and female collegiate sofitball players located in the southeastern section of the United States. Participants' 2003 batting statistics were utilized to assess batting performance, and participants must have compiled …


First Record Of A Npv Isolated From Spodoptera Littoralis (Boisd.) (Lepidoptera: Noctuidae) In Turkey And Its Molecular Identification According To The Partial Lef-8 Gene, Umut Toprak, M. Oktay Gürkan Jan 2004

First Record Of A Npv Isolated From Spodoptera Littoralis (Boisd.) (Lepidoptera: Noctuidae) In Turkey And Its Molecular Identification According To The Partial Lef-8 Gene, Umut Toprak, M. Oktay Gürkan

Turkish Journal of Biology

Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) is an important pest in Turkey and causes extensive economic losses in many cultivated crops. The viruses within the family Baculoviridae are specific pathogens of insects. The nucleopolyhedroviruses (NPVs), 1 of the 2 genera of this family, have been isolated from many insect orders, primarily from the lepidopterans. In our study, a local NPV was isolated from the larvae of Spodoptera littoralis fed in the cotton fields in southern Turkey (Mersin). For the molecular identification of the virus, polyhedra (occlusion bodies [OBs]) were isolated from insects and total DNA extraction was performed using a commercial …


Species Composition And Diversity Of Epipelic Algae In Çatal Lake (Şebinkarahisar-Giresun, Turkey), Bülent Şahi̇n Jan 2004

Species Composition And Diversity Of Epipelic Algae In Çatal Lake (Şebinkarahisar-Giresun, Turkey), Bülent Şahi̇n

Turkish Journal of Biology

The epipelic algae of Çatal Lake were studied between June and October 2002. Fifty-three taxa (39 belonging to Bacillariophyta, 8 to Chlorophyta, 5 to Cyanophyta and 1 to Euglenophyta) were determined. Based on the epipelic algal composition, Çatal Lake can be characterized as eutrophic.


Openness In The Face Of Systemic Constraints On Science, Public Participation, And The Western Australian Regional Forest Agreement, Martin Brueckner Jan 2004

Openness In The Face Of Systemic Constraints On Science, Public Participation, And The Western Australian Regional Forest Agreement, Martin Brueckner

Theses: Doctorates and Masters

The aim of this thesis is to explore the role of science and public participation in environmental policy-making processes in Australia. To this end, I analyse the Western Australian Regional Forest Agreement (RFA) process, a recent Australian Federal Government initiative designed to resolve a longstanding dispute over native forest use and management. Theoretically underpinned by an open systems approach, the thesis employs a case study method for the analysis of the RFA process, using data from three distinct sources; interviews, RFA-related literature, and media content. The analysis of the RFA occurs against the historical background to this policy process and …


The Role Of Farm Dams As Refugia For Aquatic Invertebrates In A Salinised Landscape, South Western Australia, Jean-Michel Benier Jan 2004

The Role Of Farm Dams As Refugia For Aquatic Invertebrates In A Salinised Landscape, South Western Australia, Jean-Michel Benier

Theses: Doctorates and Masters

In a salinised landscape farm dams may represent the last truly freshwater surface resource, and therefore provide refuge habitats for the biota of wetlands affected by increasing salinity. One wetland threatened by increased salinity in south-west Western Australia is Lake Toolibin. It is listed as a Wetland of International Importance under the Ramsar Convention in recognition of its high conservation value, and remediation actions to halt (and possibly reverse) further increases in salinity are being undertaken at this wetland. Farm dams act as aquatic refugia if they convey resistance and/or resilience to the biotic communities of a disturbed habitat. This …


The Use Of Proline To Determine Salt Tolerance In Eucalyptus Species And Clones, Andrew J. Woodward Jan 2004

The Use Of Proline To Determine Salt Tolerance In Eucalyptus Species And Clones, Andrew J. Woodward

Theses: Doctorates and Masters

There have been a number of studies that have examined the Eucalyptus spp. for their salt and waterlogging tolerance: but they have done so using conventional methods. A wide range of plants are known to produce greater amounts of proline when stressed, be it salt, temperature, 'drought or several other types of stress. This study looked at production of proline in salt stressed eucalypts to determine whether it can be used to differentiate between individuals andspecies. A range of Eucalyptus species and salt tolerant clones of E. camaldulensis were grown to investigate their proline response to salt stress.


Activation Kinetics Of Skinned Cardiac Muscle By Laser Photolysis Of Nitrophenyl-Egta, Hunter Martin, Marcus G. Bell, Graham C. Ellis-Davis, Robert J. Barsotti Jan 2004

Activation Kinetics Of Skinned Cardiac Muscle By Laser Photolysis Of Nitrophenyl-Egta, Hunter Martin, Marcus G. Bell, Graham C. Ellis-Davis, Robert J. Barsotti

PCOM Scholarly Works

The kinetics of Ca2+-induced contractions of chemically skinned guinea pig trabeculae was studied using laser photolysis of NP-EGTA. The amount of free Ca2+ released was altered by varying the output from a frequency-doubled ruby laser focused on the trabeculae, while maintaining constant total [NP-EGTA] and [Ca2+]. The time courses of the rise in stiffness and tension were biexponential at 23°C, Ph 7.1, and 200 Mm ionic strength. At full activation (pCa < 5.0), the rates of the rapid phase of the stiffness and tension rise were 56 ± 7 s-1 (n = 7) and 48 ± 6 s-1 (n = 11) while the amplitudes were 21 ± 2 and 23 ± 3%, respectively. These rates had similar dependencies on final [Ca2+] achieved by photolysis: 43 and 50 s-1 per Pca unit, respectively, over a range of [Ca2+] producing from 15% to 90% of maximal isometric tension. At all [Ca2+], the rise in stiffness initially was faster than that of tension. The maximal rates for the slower components of the rise in stiffness and tension were 4.1 ± 0.8 and 6.2 ± 1.0 s-1. The rate of this slower phase exhibited significantly less Ca2+ sensitivity, 1 and 4 s-1 per Pca unit for stiffness and tension, respectively. These data, along with previous studies indicating that the force-generating step in the cross-bridge cycle of cardiac muscle is marginally sensitive to [Ca2+], suggest a mechanism of regulation in which Ca2+ controls the attachment step in the cross-bridge cycle via a rapid equilibrium with the thin filament activation state. Myosin kinetics sets the time course for the rise in stiffness and force generation with the biexponential nature of the mechanical responses to steps in [Ca2+] arising from a shift to slower cross-bridge kinetics as the number of strongly bound cross-bridges increases.


The Control, Survival, And Growth Of Listeria Monocytogenes On Food Products, Richelle Lynn Beverly Jan 2004

The Control, Survival, And Growth Of Listeria Monocytogenes On Food Products, Richelle Lynn Beverly

LSU Doctoral Dissertations

Listeria monocytogenes, a ubiquitous foodborne pathogen, was recognized over 70 years ago. It is the source of the human disease listeriosis. The majority of Listeria monocytogenes that have been isolated from food product or human cases are of the serotypes ½ a, ½ b and 4b. Due to the recent outbreaks, recalls and deaths associated with Listeria monocytogenes in ready-to-eat meat products, the United States Department of Agriculture (USDA), Food Safety and Inspection Service (FSIS) on October 2, 2003 issued a directive for the control of Listeria monocytogenes on ready-to-eat products. The ready-to-eat food industry must impose a post-lethality treatment …


Spatial Econometric Analysis Of Louisiana Rural Real Estate Values, Patricia Soto Jan 2004

Spatial Econometric Analysis Of Louisiana Rural Real Estate Values, Patricia Soto

LSU Doctoral Dissertations

The general purpose of this study was to conduct a spatial analysis of the dynamics of rural land values in Louisiana. Specifically, spatial econometric procedures and hedonic price analysis were used to evaluate the impact of land characteristics on land prices across rural land markets in Louisiana. Initially, hedonic models were estimated by ordinary least squares (OLS) procedures to test for the presence of spatial autocorrelation using Lagrange Multiplier tests. Results suggested that there was spatial autocorrelation in the error terms. Hedonic models were then estimated using maximum likelihood (ML) spatial error techniques. Log likelihood numbers and likelihood ratio tests …


Examining The Relationships Between Ability Conceptions, Intrinsic Motivation, Presistence And Performance, Weidong Li Jan 2004

Examining The Relationships Between Ability Conceptions, Intrinsic Motivation, Presistence And Performance, Weidong Li

LSU Doctoral Dissertations

The purpose of this study was to examine the relationships between ability conceptions, intrinsic motivation, persistence, and performance using an interaction approach. The phase-one study revealed that participants who were more oriented toward incremental ability beliefs were likely to be more intrinsically motivated. For those who were more intrinsically motivated, they displayed more persistence and obtained better performance scores. Participants who were highly intrinsically motivated had lower performance scores as they were more oriented toward incremental ability beliefs. The phase-two study showed that participants who were more oriented toward incremental views were more intrinsically motivated, which provided evidence supporting the …


Phylogeny And Biogeography Of Wajira (Leguminosae): A Monophyletic Segregate Of Vigna Centered In The Horn Of Africa Region, Mats Thulin, Matt Lavin, Remy Pasquet, Alfonso Delgado-Salinas Jan 2004

Phylogeny And Biogeography Of Wajira (Leguminosae): A Monophyletic Segregate Of Vigna Centered In The Horn Of Africa Region, Mats Thulin, Matt Lavin, Remy Pasquet, Alfonso Delgado-Salinas

All Peer-Reviewed Publications

Evidence from chloroplast trnK and nuclear ribosomal ITS sequences and morphological data reveals that the monotypic legume genus Wajira is nested within a clade comprising the species of Vigna subgen. Macrorhynchus. This Wajira-containing clade is basally branching in a larger clade that contains many of the genera traditionally referred to as tribe Phaseoleae subtribe Phaseolinae. Wajira is thus recircumscribed to include Vigna subgen. Macrorhynchus. Given the heterogeneity of floral morphology of its constituent species, Wajira is apomorphically diagnosed by woody stems and a pollen brush that comprises an introrse linear array of unicellular hairs. This recircumscribed genus now comprises five …


Carotid Endothelial Responses To Proinflammatory Mediators, Susana M. Tente Jan 2004

Carotid Endothelial Responses To Proinflammatory Mediators, Susana M. Tente

Seton Hall University Dissertations and Theses (ETDs)

No abstract provided.


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 2004

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Front Matter Jan 2004

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Flow Cytometry Used To Assess Genetic Damage In Frogs From Farm Ponds, Bartholomew L. Bly, Melinda G. Knutson, Mark B. Sandheinrich, Brian R. Gray, Dean A. Jobe Jan 2004

Flow Cytometry Used To Assess Genetic Damage In Frogs From Farm Ponds, Bartholomew L. Bly, Melinda G. Knutson, Mark B. Sandheinrich, Brian R. Gray, Dean A. Jobe

Journal of the Iowa Academy of Science: JIAS

Flow cytometry (FC) is a laboratory method used to detect genetic damage induced by environmental contaminants and other stressors in animals, including amphibians. We tested FC methods on three species of ranid frogs collected from farm ponds and natural wetlands in southeastern Minnesota. We compared FC metrics for Rana clamitans between ponds with direct exposure to agricultural contaminants and reference (unexposed) ponds. Concentrations of atrazine in water from our farm ponds ranged from 0.04 to 0.55 ppb. We found that R. clamitans from exposed ponds had DNA content similar to frogs from unexposed ponds. Pond-averaged C-values (a measure of DNA …


Beach-Cast Wrack As A Determinant Of Macroinvertebrate Assemblages And Trophic Subsidy To Sandy Beach Ecosystems, Rebecca Ince Jan 2004

Beach-Cast Wrack As A Determinant Of Macroinvertebrate Assemblages And Trophic Subsidy To Sandy Beach Ecosystems, Rebecca Ince

Theses : Honours

The transport of detached macrophytes from seagrass meadows and reefs, otherwise known as wrack, has been identified in some parts of the world as a marine subsidy which can increase the productivity of coastal ecosystems. The aim of this study was to determine whether wrack deposits act as a marine subsidy on sandy beaches in Perth, by determining whether it influences the structure of, and is a source of nutrient to, the macroinvertebrate communities in this ecosystem. This was achieved by examining the abundance, composition and nutrient source of macrofauna, including epifauna, infauna and flying fauna, on three sandy beaches …


Growth Trends And Water Use Efficiency Of Pinus Pinaster Ait. In Response To Historical Climate And Groundwater Trends On The Gnangara Mound, Western Australia, Lindsay Bourke Jan 2004

Growth Trends And Water Use Efficiency Of Pinus Pinaster Ait. In Response To Historical Climate And Groundwater Trends On The Gnangara Mound, Western Australia, Lindsay Bourke

Theses : Honours

In Western Australia, groundwater accounts for about 57% of Perth's water supply. The majority of this is from the Gnangara Mound, the largest superficial aquifer on the Swan Coastal Plain. Prior to the mid 1970's groundwater of the superficial aquifer reached a semi-steady state, however since this period levels have been steadily falling. This decline coincides with a dramatic change in Perth's climate, groundwater abstraction and maturation of pine plantations. The influence of pine plantations upon groundwater recharge is well understood, however there is paucity of information about groundwater use, in particular whether pines directly access shallow groundwater resources. This …


Banksia Woodland Resilience To Groundwater Drawdown On The Gnangara Mound, Llewellyn Broun Jan 2004

Banksia Woodland Resilience To Groundwater Drawdown On The Gnangara Mound, Llewellyn Broun

Theses : Honours

Water is considered to be the major limiting resource to plant growth and survival in regions with a Mediterranean-type climate, particularly during dry summer periods when low water potentials develop (Poole et al., 1981; Miller et al., 1983-84; Mooney and Miller, 1985; Stock et al., 1992). The Swan Coastal Plain is situated within this climatic region and interactions between the climate, soil and geology has an important bearing on the water requirements of the associated Banksia woodlands (Dodd and Heddle, 1989). The assessment of the condition of any vegetative community and in this case, the resilience of Banksia woodlands to …


Seasonal Effects On Diet Of Two Arid Zone Dasyurids, Dasycercus Cristicauda And Ningaui Ridei (Dasyuridae, Marsupialia), Leisa Turner Jan 2004

Seasonal Effects On Diet Of Two Arid Zone Dasyurids, Dasycercus Cristicauda And Ningaui Ridei (Dasyuridae, Marsupialia), Leisa Turner

Theses : Honours

Seasonal fluctuations in rainfall and food availability are thought to change populations of arid zone mammals dramatically over time. Competition between similar species for limited food resources is believed to be a major factor in the evolution and maintenance of population assemblages. Animals foraging in arid regions must be responsive to the unreliable distribution of nutrients and food resources to ensure the survival of viable populations. Adaptive physiological traits and behavioural mechanisms of arid zone animals allow them to survive extreme conditions and the ability to switch between prey species in adverse conditions is an advantageous strategy. This study was …


The Effectiveness Of Post-Fire Weed Management And The Germination Ecology Of Selected Invasive Weed Species Of Bold Park, Brett Neasham Jan 2004

The Effectiveness Of Post-Fire Weed Management And The Germination Ecology Of Selected Invasive Weed Species Of Bold Park, Brett Neasham

Theses : Honours

Bold Park is a 437 hectare A class reserve with high conservation value. Bold park is located on the Swan Coastal Plain, approximately 11 km west of the Perth CBD. Bold park is one of the few remaining coastal bushland reserves on the Swan Coastal Plain. High levels of floristic and faunal diversity contribute to Bold Park's conservation value. Weed invasion in Bold Park is reducing floristic diversity and is modifying ecosystem processes. Principle in the modified ecosystem processes is fire. While fire is a natural disturbance event in the bushland of the south-west of Western Australia, altered fire regimes …


Investigation Into The Use Of Bait Stations For The Control Of The European Wild Rabbit (Oryctolagus Cuniculus) In The Urban Bushland Reserve Of Bold Park, Perth, Western Australia, Malin Kordes Jan 2004

Investigation Into The Use Of Bait Stations For The Control Of The European Wild Rabbit (Oryctolagus Cuniculus) In The Urban Bushland Reserve Of Bold Park, Perth, Western Australia, Malin Kordes

Theses : Honours

European rabbits in Australia have a significant impact on the environment and the economy. It is therefore necessary to implement control programs. In rural areas a number of methods including warren ripping and poisoning are frequently used. In urban areas though, rabbit control is not as easily accomplished because the use of many control methods is not appropriate. For example, the poison 1080 often cannot be used due to public health concerns and warren ripping cannot be used in conservation areas. Poisoning with pindone, an anticoagulant, is therefore one of few options available to the managers of urban reserves. However, …


Plant Surrogacy: An Evaluation Of Its Use And Application In The Effort To Conserve Ground Dwelling Invertebrates, Kerry Leigh Ironside Jan 2004

Plant Surrogacy: An Evaluation Of Its Use And Application In The Effort To Conserve Ground Dwelling Invertebrates, Kerry Leigh Ironside

Theses : Honours

A study conducted in the Ridges State Forest, Yanchep was designed to investigate the relationship between plant species richness, vegetation association and ground dwelling invertebrate species richness. Four plant communities were sampled at two scales of measurement. Two treatments were located in woodland and two in heath. Within each vegetation association, plant communities that were representative of both high and low species richness were selected. Three invertebrate orders, Araneae, Coleoptera and Araneae were sorted to morphospecies level. Ordinal richness was also investigated. Two-way ANOVAs indicated that there was no relationship between plant species richness, vegetation association· or the interaction between …


Effect Of Light Duration On Pulvinar Motor Organ Movements In Phaseolus Vulgaris, Thomas William Rinehart Jan 2004

Effect Of Light Duration On Pulvinar Motor Organ Movements In Phaseolus Vulgaris, Thomas William Rinehart

Presidential Scholars Theses (1990 – 2006)

With a well established model in place, the main objective of this study will be to determine if the pulvinar motor organs have a threshold radiation level to elicit paraheliotropic movements. Plants will be illuminated with full spectrum light at varying intensities and periods. Observation will take place minute-by-minute in an effort to denote certain lighting conditions which might trigger paraheliotropism.


Theoretical Neuroscience: Modeling The Activation Mechanism Of Potassium Channels In Neurons, Kevin Twedt Jan 2004

Theoretical Neuroscience: Modeling The Activation Mechanism Of Potassium Channels In Neurons, Kevin Twedt

Presidential Scholars Theses (1990 – 2006)

We have modeled the electrostatic interaction between the S4 segment of the potassium channel molecule and the surrounding water molecules on both the intracellular and extracellular sides of the neural axon cell membrane. Two methods were used to approximate this interaction: (i) a macroscopic evaluation in which the water was treated as a dielectric medium with dielectric constant 80; (ii) a microscopic evaluation considering the effects of each individual water molecule fixed in position within the water pockets surrounding the S4 segment. The potential energy of the S4 due to the water pockets was plotted against the rotation of the …


116th Annual Meeting Of The Iowa Academy Of Science [Program, 2004], Iowa Academy Of Science Jan 2004

116th Annual Meeting Of The Iowa Academy Of Science [Program, 2004], Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Notes Page --- 3
Friday Program Summary --- 4
Senior Academy Poster Presentation Titles --- 5
General Session Speakers --- 7
Symposia Programs --- 8
Saturday Program Summary --- 9
Section Meeting Programs (Alphabetical by Section) --- 9
2004 Awards --- 14
Abstracts (by Section) --- 15
Author Index --- 42