Digital Commons Network^™

Quantifying The Adaptive Cycle, David G. Angeler, Craig R. Allen, Ahjond S. Garmestani, Lance H. Gunderson, Olle Hjerne, Monika Winder

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The adaptive cycle was proposed as a conceptual model to portray patterns of change in complex systems. Despite the model having potential for elucidating change across systems, it has been used mainly as a metaphor, describing system dynamics qualitatively. We use a quantitative approach for testing premises (reorganisation, conservatism, adaptation) in the adaptive cycle, using Baltic Sea phytoplankton communities as an example of such complex system dynamics. Phytoplankton organizes in recurring spring and summer blooms, a well-established paradigm in planktology and succession theory, with characteristic temporal trajectories during blooms that may be consistent with adaptive cycle phases. We used long-term …

Measuring Usability In The Database Review Process: Results From A Pilot, Ilana Stonebraker

Libraries Faculty and Staff Scholarship and Research

The objective of this study is to examine the impact of incorporating user experience study methods into library database purchase and renewal. Purdue University Libraries introduced a heuristic evaluation into an existing yearly database review. Commonly used in usability and human factors engineering, heuristic evaluation is an innovative and dynamic method for librarians to evaluate electronic resources and provide expert feedback to database vendors. A form was developed to streamline the process for the librarians involved. In total, eight librarians evaluated 37 databases as a pilot project. This paper describes the outcome of the pilot.

The Effect Of Insularity On The Seasonal Population Structure Of Mesobuthus Gibbosus (Scorpiones: Buthidae), Dimitris Kaltsas, Iasmi Stathi, Moysis Mylonas

Euscorpius

We compared the population structure of Mesobuthus gibbosus from autumn to mid-summer at two similar phryganic ecosystems, one in continental Greece (Thessalia, near Volos city) and one in insular Greece (eastern Crete). Data were collected monthly using the capture-recapture method. At both sites, density was low during the cold period and increased towards summer. During the samplings, only a small percentage of each population was present. Population density and co-occurrence of scorpions with scorpions or other animals was higher in Crete than in Volos, probably due to the higher inter- and intraspecific competition in Volos. The population structure of the …

Divergent Responses Of Cryptic Invasive Watermilfoil To Treatment With Auxinic Herbicides In A Large Michigan Lake, Syndell R. Parks

Masters Theses

Invasive plants are a major concern for environmental managers. Cryptic invasive taxa present additional challenges because of their potential to respond differently to management efforts. Invasive Eurasian watermilfoil (Myriophyllum spicatum) and hybrid watermilfoil (Myriophyllum spicatum x Myriophyllum sibiricum) cannot be reliably distinguished based on morphological characters and are therefore cryptic taxa. Laboratory studies show that on average, hybrid watermilfoil grows faster, branches more, and is less responsive to standard control measures developed for Eurasian watermilfoil. These laboratory results predict less effective control of hybrid watermilfoil in mixed populations treated uniformly with one of these control measures. However, to date there …

Population Status And Habitat Preferences Of Critically Endangered Dipterocarpus Littoralis In West Nusakambangan, Indonesia, Iyan Robiansyah, Anthony John Davy

Makara Journal of Science

The conservation of the endemic tree species Dipterocarpus littoralis (Bl.) Kurz. is hampered by the paucity of information on its population biology and ecology. Consequently, a targeted survey was carried out in the West Nusakambangan Nature Reserve to assess its population size and structure as well as habitat preferences. In total, 676 individuals of D. littoralis were located at 52 locations, with an extent of occurrence of 3.66 km2 and an area of occupancy of 1.71 km2. The population had an inverse-J-shaped distribution of diameter at breast height (DBH), with 63% of individuals in the 0-5 cm class and another …

The Evolutionary Selective Pressures Exerted On A3 Actinobacteriophages, Cheyenne Weeks-Galindo

Masters Theses, 2010-2019

This study identified evolutionary selective pressures within subcluster A3 actinobacteriophages. These phages are able to infect the clinically important genus Mycobacterium. Understanding the selective pressures on genes in these phage genomes is a step toward understanding the adaptations that result from short-term and long-term associations of phages and bacteria that have been co-evolving for perhaps billions of years. In this study 149 phamilies (phage protein families) of homologous gene sequences were analyzed using Datamonkey. Complete data were obtained for 57 phamilies. Of these, eleven phamilies were affected by recombination, three showed evidence of predominantly diversifying selection, and twenty-four have …

Prioritizing The Management Of Arundo Donax: Recommendations For Removal And Revegetation In California Riparian Habitats, Matthew S. Waterworth

Master's Projects and Capstones

The highly invasive grass species, giant reed (Arundo donax), has been a major contributor to riparian habitat degradation in California for over 50 years. Several modes of vegetative reproduction have allowed this alien species to take advantage of fluvial processes and rapidly spread within California watersheds. A. donax dramatically alters hydrologic regimes, displaces native vegetation, and removes food and habitat for native wildlife. It is widely accepted that removal of this invasive on a watershed scale is critical to restore natural riparian processes and facilitate the reestablishment of native flora and fauna. The following study analyzed the efficacy of …

Utilizing Ecological Connectivity In California Desert Wilderness Preservation, Lauren Kahal

Master's Projects and Capstones

The Wilderness Act of 1964 gave the federal land management agencies—the National Park Service, United States Forest Service, U.S Fish and Wildlife Service, and Bureau of Land Management—the authority to identify, propose, and manage lands as wilderness. Wilderness, once approved by Congress for inclusion in the National Wilderness Preservation System, is offered the highest form of land preservation in the nation. However, the wilderness identification process used by the implementing agencies is based on a half-century old statute with an aging definition of wilderness. While designated wilderness can protect the plant and wildlife communities within its borders from direct anthropogenic …

Trophic Pathways Supporting Juvenile Chinook And Coho Salmon In The Glacial Susitna River, Alaska: Patterns Of Freshwater, Terrestrial, And Marine Resource Use Across A Seasonally Dynamic Habitat Mosaic, Kristin M. Rine

Biological Sciences

In large, seasonally dynamic and spatially complex watersheds, the availability and relative importance of various food resources for stream fishes can be expected to vary substantially. While numerous studies have attempted to uncover the trophic linkages that support stream salmonids, much of these efforts have occurred at small scales that disregard variability of food resources inherent in lotic systems. This study aimed to determine large-scale patterns in the contributions of freshwater, terrestrial, and marine-derived food resources to juvenile Chinook and Coho salmon (Oncorhynchus tshawytscha and O. kisutch) in the large, glacially influenced Susitna River, Alaska. I quantified diet patterns both …

Sea-Ice Habitat Preference Of The Pacific Walrus (Odobenus Rosmarus Divergens) In The Bering Sea: A Multiscaled Approach, Alexander Edward Sacco

Geosciences

The goal of this thesis is to define specific parameters of mesoscale sea-ice seascapes for which walruses show preference during important periods of their natural history. This research thesis incorporates sea-ice geophysics, marine-mammal ecology, remote sensing, computer vision techniques, and traditional ecological knowledge of indigenous subsistence hunters in order to quantitatively study walrus preference of sea ice during the spring migration in the Bering Sea. Using an approach that applies seascape ecology, or landscape ecology to the marine environment, our goal is to define specific parameters of ice-patch descriptors and mesoscale seascapes in order to evaluate and describe potential walrus …

Population Density Of The Florida Scrub Lizard (Sceloporus Woodi) In Managed Sand Pine Scrub And Longleaf Pine Sandhill Habitats, Matthew D. Kaunert, Lance D. Mcbrayer

Biology: Faculty Publications

Studies investigating managed landscapes are of increasing importance, as fragmentation is a known cause of biodiversity loss. From June to September 2012, we sampled populations of the rare, endemic Florida Scrub Lizard (Sceloporus woodi) across the Ocala National Forest (ONF) to compare lizard density across two managed habitat types. Florida Scrub habitat in the ONF is clearcut and roller-chopped, whereas Longleaf Pine habitat is managed via prescribed burning. We sampled 10 stands of Florida Scrub (2–3 y post disturbance) and 10 stands of Longleaf Pine (1 y post-disturbance) for lizards. We compared lizard density between the interior of …

Dietary Patterns And Prostate Cancer Aggressiveness In African-American And European-American Men, Lara Ryan Schneider

Theses and Dissertations

Several foods and nutrients have been linked to prostate cancer risk, but the effect of overall diet on prostate cancer outcomes is not well understood. Previous research has primarily examined a posteriori dietary patterns in relation to prostate cancer; studies that have used a priori dietary patterns and their relationship with prostate cancer have been inconclusive. Furthermore, racial differences in prostate cancer incidence and aggressiveness are not well understood. Data from the case-only North Carolina-Louisiana Prostate Cancer Project (PCaP) was used to examine the association between overall dietary pattern, as measured by the Mediterranean Diet (MED) score and the Dietary …

Oxidative Stress In Avian Embyros, Toshi Tsunekage

Dissertations

Oxidative stress has been implicated in mediating trade-offs in the evolution of life histories. Oxidative stress results from an imbalance in the production of free radicals and an organism’s antioxidant defenses. Higher metabolic rates associated with more rapid growth and shorter development periods may increase oxidative stress and accumulated cellular damage in embryonic tissues. In my dissertation I explored oxidative stress and antioxidant defenses in avian embryos. I measured levels of oxidative stress in tissues of different stage embryos of Japanese quail (Coturnix japonica), and tested if patterns of lipid peroxidation could be explained by changes in the developing embryo’s …

Connectivity Of Coastal And Oceanic Ecosystems: Pelagic Habitat Use By Juvenile Reef Fishes In The Gulf Of Mexico, Katie Bowen

HCNSO Student Theses and Dissertations

The assemblage structure, abundance, biomass, and vertical distribution of juvenile reef fishes in the offshore pelagic habitat of the northern Gulf of Mexico are described as part of the NOAA-supported Offshore Nekton Sampling and Analysis Program. The results presented here are from a 3-month, continuous sampling series in 2011 in which discrete depth strata from 0 to 1500 m were sampled using a 10-m² MOCNESS midwater trawl. This is the first study to examine pelagic juvenile reef fish distributions across the entire oceanic northern Gulf of Mexico seaward of the continental shelf break after the Deepwater Horizon Oil Spill. …

Reframing The Debate About The Socialization Of Children: An Environmental Paradigm, Barbara Bennett Woodhouse

University of Chicago Legal Forum

No abstract provided.

A Qualitative Study Of Epiphytic Algae (Diatom) On Some Aquatic Plants In Al-Auda Marshes Within Maysan Province / Southern Iraq, Jinan S. Al Hassany, Alaa I. M. Al-Bueajee

Baghdad Science Journal

The study conducted on the compositions of epiphytic diatoms on three taxa of aquatic plants were selected (Phragmites australis Trin ex stand , Ceratophyllum demersum L. and Typha domengensis Pers) in three sites within Al-Auda Marsh, from autumn 2013 to summer 2014 . The study was measured physical and chemical factors of all the study sites, such as: air temperature, power of hydrogen (pH), electrical conductivity (EC), salinity (S‰), total hardness(TH), dissolved oxygen (DO), and plant nutrient. The results showed that water of marsh was oxygenated and it was very hard. A total of 111 taxa of phytoplankton were identified, …

Spatial And Dietary Overlap Creates Potential For Competition Between Red Snapper (Lutjanus Campechanus) And Vermilion Snapper (Rhomboplites Aurorubens), William T. Davis, J. Marcus Drymon, Sean P. Powers

University Faculty and Staff Publications

Understanding the complex nature of direct and indirect species interactions is a critical precursor to successful resource management. In the northern Gulf of Mexico fisheries ecosystem, red snapper (Lutjanus campechanus) and vermilion snapper (Rhomboplites aurorubens) are two commercially harvested species within a larger reef fish complex. These two species share similar habitats and diets; however, little is known about how these species partition habitat and dietary resources. In this study we examined the extent of spatial and dietary overlap between red snapper and vermilion snapper, and experimentally compared their feeding behavior. Field data from multiple gear …

Object-Based Crop Classification With Landsat-Modis Enhanced Time-Series Data, Qingting Li, Cuizhen Wang, Bing Zhang, Linlin Lu

Faculty Publications

Cropland mapping via remote sensing can provide crucial information for agri-ecological studies. Time series of remote sensing imagery is particularly useful for agricultural land classification. This study investigated the synergistic use of feature selection, Object-Based Image Analysis (OBIA) segmentation and decision tree classification for cropland mapping using a finer temporal-resolution Landsat-MODIS Enhanced time series in 2007. The enhanced time series extracted 26 layers of Normalized Difference Vegetation Index (NDVI) and five NDVI Time Series Indices (TSI) in a subset of agricultural land of Southwest Missouri. A feature selection procedure using the Stepwise Discriminant Analysis (SDA) was performed, and 10 optimal …

Total Dietary Fiber Content Of Selected Traditional Beverages In Egypt: A Brief Profile, Basil H. Aboul-Enein

Health & Wellness Department Faculty Publications and Research

Escalating obesity rates have become a major public health concern in North Africa and the Middle East. Culturally-congruent dietary health education and strategies continue to be warranted to address this increasing public health crisis. Knowledge and familiarity with traditional foods and their nutritive value would assist public health practitioners in becoming culturally competent when educating on healthy eating patterns. The aim of this study is to provide a brief dietary profile of the total dietary fiber (TDF) contents of selected traditional beverages in Egypt. Five cookbooks for Egyptian food recipes were reviewed for traditional beverages. Beverage recipes (n = …

Lead Exposure In Children Through Water And Soil, Sravya Maru

Environmental Management & Risk Assessment (PH 560)

Lead is a metal which has the ability to spread in the earth’s crust and has corrosive property. It is a naturally occurring metal which is soft in nature. Lead exposure in children is through various pathways and the major concentrated sources are the soil and drinking water. Children are most susceptible to lead exposure is due to their growing/developing bodies which are very sensitive to lead. Lead poisoning in children is a preventable environmental disease affecting many children around the world. This paper discusses how soil and water plays a major role in lead exposure to children’s routine life. …

Mens Life History, Testosterone, And Health, Louis Calistro Alvarado

Anthropology ETDs

Testosterone is hypothesized to mediate life history trade-offs between reproduction and survival in men, promoting mating effort over other forms of investment, which entails energetic and mortality costs. Sexually dimorphic musculature represents one form of somatic investment in mating. Favorable energy availability is posited to promote preferential investment in mating effort through upregulated testosterone production and augmented musculature, whereas nutritional constraint is predicted to downregulate testosterone to facilitate a diminished, thriftier phenotype. Furthermore, life history trajectories influencing mens testosterone levels have important health implications for androgen-sensitive disease. Here, I examine broad features of men's life history and health, and their …

Effects Of Short-Term Soil Conditioning By Cheatgrass And Western Wheatgrass, James J. O'Connor, Janet S. Prevey

The Prairie Naturalist

The exotic grass Bromus tectorum (cheatgrass) is a ubiquitous invader in the western USA. Cheatgrass is a proficient competitor, frequently displacing native plants, forming monotypic stands and reducing biodiversity in ecosystems it invades. Our experiment tested whether short-term soil modification by cheatgrass and a predominant native grass, Pascopyrum smithii (western wheatgrass), affected subsequent growth of both species. We compared productivity of cheatgrass and western wheatgrass by harvesting aboveground biomass of plants grown in either cheatgrass- or western wheatgrass-conditioned soils over two simulated growing seasons. Results indicated that cheatgrass soils do not inhibit the productivity of the native grass, but do …

Remembering Paul B. Kannowski, Robert Seabloom

The Prairie Naturalist

I am saddened to report that Dr. Paul Kannowski passed away 3 September 2015, succumbing to cancer. He was 88. A native of Grand Forks, Paul attended the University of North Dakota for his B.S. and M.S. degrees, and the University of Michigan for his Ph.D. He joined the University of North Dakota Biology Department in 1957, retiring in 1990 after 33 years of service

Paul chaired UND’s Biology Department twice, totaling 13 years, considered to be a remarkable achievement by many of us who have been exposed to that task! His leadership was instrumental in the nearly exponential growth …

The Impact Of Temperature, Ph And Environmental Heterogeneity On Prokaryotic Diversity In Yellowstone National Park Thermal Springs, Xiaoben Jiang

Biology ETDs

Yellowstone National Park (YNP) is one of the largest and most diverse hydrothermal areas on Earth. Extensive culture-independent studies in YNP thermal springs have shown dramatic taxonomic and metabolic diversity in microbial communities. We conducted a survey of bacterial communities along temperature gradients in three alkaline springs with similar geochemistries at the local scale. With these data, we investigated the influence of environmental variables on bacterial community diversity and assemblages along a broad temperature range using high throughput 454 pyrosequencing. Previous studies have suggested that pH is the driver of microbial diversity in thermal springs among geographical regions or at …

Sampling Terrestrial Arthropod Biodiversity: A Case Study In Arkansas, Michael Joseph Skvarla

Graduate Theses and Dissertations

The Interior Highlands is a biodiversity hotspot, with at least 200 known endemic species, but is understudied compared to hotspots, such as the Southern Appalachians. In order to begin to rectify this issue, a nine month study was conducted from mid-March through early December at a 4 ha site at Steel Creek, Buffalo National River, in Newton County, Arkansas. Thirteen collecting methods were employed, including three colors of Lindgren funnel trap, five colors of pan trap, Malaise traps, canopy traps with upper and lower collectors, pitfall traps, and Berlese-Tullgren extraction of leaf litter, which resulted in the collection of 1311 …

Nephrology Care Prior To End-Stage Renal Disease And Outcomes Among New Esrd Patients In The Usa, Brenda W. Gillespie, Hal Morgenstern, Elizabeth Hedgeman, Anca Tilea, Natalie Scholz, Tempie Shearon, Nilka R. Burrows, Vahakn B. Shahinian, Jerry Yee, Laura Plantinga, Neil R. Powe, William Mcclellan, Bruce Robinson, Desmond E. Williams, Rajiv Saran

Nephrology Articles

BACKGROUND: Longer nephrology care before end-stage renal disease (ESRD) has been linked with better outcomes.

METHODS: We investigated whether longer pre-end-stage renal disease (ESRD) nephrology care was associated with lower mortality at both the patient and state levels among 443 761 incident ESRD patients identified in the USA between 2006 and 2010.

RESULTS: Overall, 33% of new ESRD patients had received no prior nephrology care, while 28% had received care for >12 months. At the patient level, predictors of >12 months of nephrology care included having health insurance, white race, younger age, diabetes, hypertension and US region. Longer pre-ESRD nephrology …

Safe Sleep Education And Staff Compliance, Shayla M. Hadley

The Eleanor Mann School of Nursing Undergraduate Honors Theses

The purpose of this project was to evaluate compliance with the teaching and documentation of safe sleep practices within a pediatric unit. The objective was to increase the percentage of the charts of patients one year of age and younger that have documented safe sleep teaching at the level of compliance with the department policy. This change in compliance was measured by determining the percentage of patient charts having documented safe sleep teaching at the level of compliance prior to the implementation of mandatory staff education as compared to the percentage of charts with documented safe sleep teaching at the …

Ecosystem Response To Recent Climate Change In Alpine Environments, Patrick Shawn Sawyer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recent variations in meteorological conditions indicate the earth’s climate is changing in ways that can impact delicate ecological balances in sensitive regions. These impacts threaten the essential services provided by such ecosystems. Determining how climate changes are affecting the biosphere is essential to adapt and mitigate harmful consequences. In order to mitigate the negative effects of climate change and adapt to shifting ecological resource constraints, it is imperative to locate such changes and determine vulnerability of ecological resources to changing environmental conditions.

Identifying climate driven ecological changes faces numerous challenges given the reliance on vegetation indices as the primary measure …

Modelling Water Uptake Provides A New Perspective On Grass And Tree Coexistence, Michael G. Mazzacavallo, Andrew Kulmatiski

Wildland Resources Faculty Publications

Root biomass distributions have long been used to infer patterns of resource uptake. These patterns are used to understand plant growth, plant coexistence and water budgets. Root biomass, however, may be a poor indicator of resource uptake because large roots typically do not absorb water, fine roots do not absorb water from dry soils and roots of different species can be difficult to differentiate. In a sub-tropical savanna, Kruger Park, South Africa, we used a hydrologic tracer experiment to describe the abundance of active grass and tree roots across the soil profile. We then used this tracer data to parameterize …

Prevalence Of Tick-Borne Pathogens In Small Mammals And White-Tailed Deer In Southeast Nebraska, Tim M. Hotaling

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

The prevalence of tick-borne diseases has been increasing in the United States for the past couple decades. Studies have been conducted throughout the US identifying tick-borne disease pathogens as well as their hosts and prevalence. Research was conducted in Nebraska to determine the presence of some tick-borne disease pathogens, their vectors, and their hosts, with emphasis made on Borrelia spp., Rickettsia rickettsii, and Ehrlichia chaffeensis.

Small rodents in southeast Nebraska were trapped and sampled at eight study sites using live capture traps. Captured rodents were assessed for active parasitism by ticks which were collected and placed in alcohol. …