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Full-Text Articles in American Studies

Review Of Conspecific Attraction And Area Sensitivity Of Grassland Birds, David R.W. Bruinsma, Nicola Koper Oct 2012

Review Of Conspecific Attraction And Area Sensitivity Of Grassland Birds, David R.W. Bruinsma, Nicola Koper

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Many species of grassland birds are area sensitive, which may exacerbate the ecological effects of the extensive loss and fragmentation of grasslands that has taken place across the northern Great Plains. However, the reasons for this area sensitivity are unclear, as vegetation structure, matrix composition, and restriction of movements among patches do not seem to provide viable explanations for species native to grasslands. Con specific attraction, whereby species are behaviorally stimulated to select habitat or establish territories near individuals of the same species, may help explain this area sensitivity. We review and discuss theoretical and empirical research on avian conspecific …


New Distributional Records Of Great Plains Pseudo Scorpions (Arachnida: Pseudoscorpiones), Paul O. Cooney, James A. Kalisch Oct 2012

New Distributional Records Of Great Plains Pseudo Scorpions (Arachnida: Pseudoscorpiones), Paul O. Cooney, James A. Kalisch

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Pseudoscorpions are tiny, oval, brown, flattened arachnids that possess large "pinchers" in front of the body for capturing smaller prey. They generally live in forested habitats in soil litter or beneath loose bark. It has been presumed that pseudoscorpions are scarce in the Great Plains, except for along rivers, due to harsh climatic conditions. However, new records of pseudo scorpions from the Great Plains were derived from identification of specimens obtained from university and college collections, and from specimens collected by the first author. Records provided new revelations about distributions of not only the more commonly known pseudoscorpion species but …


Initial Changes In Species Cover Following Savanna Restoration Treatments In Western Iowa, David A. Mckenzie, Thomas B. Bragg, David M. Sutherland Oct 2012

Initial Changes In Species Cover Following Savanna Restoration Treatments In Western Iowa, David A. Mckenzie, Thomas B. Bragg, David M. Sutherland

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Study areas in the Iowa Loess Hills were used to evaluate short-term responses of understory species to three treatment methods designed to facilitate restoration of Quercus macrocarpa savanna. Treatments included burning alone, burning with thinning, and burning with clear-cutting. Plant abundance and diversity were compared before treatment and one year after treatment. Ninety-nine plant species were identified during the study, of which 40 were new following treatment, although most of these were forest associates. Increases in diversity of understory species were observed after treatment, particularly in plots with combined burning and thinning. The forb group was most consistent in response …


Pillar, Samantha R. (Fa 162), Manuscripts & Folklife Archives Jul 2012

Pillar, Samantha R. (Fa 162), Manuscripts & Folklife Archives

Folklife Archives Finding Aids

Finding aid and full-text scan of paper (Click on “Additional Files” below) for Folklife Archives Project 162. This collection contains a paper entitled “Going Hog Wild in Logan County,” about William Warren Morton Sr. and his work in the swine industry. This paper was written by Samantha Pillar as a part of a class at Western Kentucky University in the fall of 1994. Several photocopied images are included in the paper.


Analysis Of Variable Effects On Presence Of Cryptosporidium Oocysts And Giardia Cysts In Effluent Water From Wastewater Treatment Utilities In Florida From 1998 To 2010, Katherine Jane Barkan Jul 2012

Analysis Of Variable Effects On Presence Of Cryptosporidium Oocysts And Giardia Cysts In Effluent Water From Wastewater Treatment Utilities In Florida From 1998 To 2010, Katherine Jane Barkan

USF Tampa Graduate Theses and Dissertations

The concern of a Cryptosporidium or Giardia waterborne outbreak due to treated wastewater has had water treatment utilities using some of the highest water cleansing technologies available. Cryptosporidiosis and Giardiasis are severe diarrheal diseases which can lead to death, thus it is important that appropriate steps are taken to assure these parasites are not present in the effluent of treated wastewater. This study examined the results of 863 assays for Giardia and Cryptosporidium on the effluent of wastewater treatment facilities and found that county of collection, watershed of collection, and laboratory analyzing the sample have the most significant impact on …


Effects Of Short Shoot Number And Presence Of An Apical Meristem On Rhizome Elongation, New Short Shoot Production, And New Rhizome Meristem Production Of Thalassia Testudinum Banks And Solander Ex König Planting Units In Tampa Bay., Michael Vearl Meads Jul 2012

Effects Of Short Shoot Number And Presence Of An Apical Meristem On Rhizome Elongation, New Short Shoot Production, And New Rhizome Meristem Production Of Thalassia Testudinum Banks And Solander Ex König Planting Units In Tampa Bay., Michael Vearl Meads

USF Tampa Graduate Theses and Dissertations

Thalassia testudinum Banks and Solander ex König is the dominant seagrass in the Gulf of Mexico, Caribbean and the West Coast of Florida, yet little rhizome elongation, new short shoot production, or new rhizome meristem production data has been collected via direct measurement. A study of the rhizome growth of T. testudinum was completed in December 2004 in southern Tampa Bay that determined growth after 26.5 months. Two PVC planting frames each containing four rhizomes with 2 short shoots, two rhizomes with 4 short shoots, and two rhizomes with 8 short shoots were planted next to existing T. testudinum beds …


Reproductive Biology Of The Southern Dwarf Siren, Pseudobranchus Axanthus, In Southern Florida, Zachary Cole Adcock Jul 2012

Reproductive Biology Of The Southern Dwarf Siren, Pseudobranchus Axanthus, In Southern Florida, Zachary Cole Adcock

USF Tampa Graduate Theses and Dissertations

The salamander family Sirenidae is composed of two extant genera, Siren and Pseudobranchus, each with two known species. Several questions regarding Sirenidae life history persist, and much of the available life history data for Pseudobranchus are attributed to studies of P. axanthus in northern Florida. Information on the reproductive biology of P. axanthus is limited, and historical references often suggest contradictory results. This study was undertaken to clarify information and expand on the limited data regarding P. axanthus reproductive biology, specifically for southern Florida populations. The study population was most likely the P. a. belli subspecies. P. axanthus in southern …


Systematic Review Of Core Muscle Electromyographic Activity During Physical Fitness Exercises, Jason Martuscello Jul 2012

Systematic Review Of Core Muscle Electromyographic Activity During Physical Fitness Exercises, Jason Martuscello

USF Tampa Graduate Theses and Dissertations

Activating the core muscles through exercise training programs is believed to be important for athletic performance. Considerable attention has been credited to the lumbar multifidus, transverse abdominis, and quadratus lumborum in designing exercise training programs. Numerous core exercise claims and recommendations abound in the fitness and physical therapy communities touting a superior core challenge for these muscles. The plethora of core activation literature with conflicting outcomes has convoluted the process of choosing exercises for an optimal core training approach. Although an abundance of research studies have quantified the muscle activity, collectively, a consensus on the type of exercise that elicits …


Availability And Quality Of Vegetation Affects Reproduction Of The Gopher Tortoise (Gopherus Polyphemus) In Improved Pastures, Anna Louise Hathaway Jun 2012

Availability And Quality Of Vegetation Affects Reproduction Of The Gopher Tortoise (Gopherus Polyphemus) In Improved Pastures, Anna Louise Hathaway

USF Tampa Graduate Theses and Dissertations

As part of a state-funded Gopher Tortoise (Gopherus polyphemus Daudin) translocation project, I monitored actively grazed improved pastures to determine if they could serve as suitable recipient sites for the threatened Gopher Tortoise displaced by human development. For cattle ranches to be considered suitable recipient sites females must be able to acquire sufficient energy to produce a clutch of viable eggs, and sufficiently high quality vegetation must be available to support juvenile recruitment into the population. Vegetation surveys were conducted to determine the composition and percent cover of plant species, especially those containing high amounts of nutrients, specifically nitrogen. Resident …


The Role And Regulation Of Nsars: A Cell-Envelope Stress Sensing Two-Component System In Staphylococcus Aureus, Stacey Lynn Kolar Jun 2012

The Role And Regulation Of Nsars: A Cell-Envelope Stress Sensing Two-Component System In Staphylococcus Aureus, Stacey Lynn Kolar

USF Tampa Graduate Theses and Dissertations

Abstract

S. aureus has 16 predicted two-component systems (TCS) that respond to a range of environmental stimuli, and allow for adaptation to stresses. Of these 16, three have no known function, and are not homologous to any other TCS found in closely related organisms. NsaRS is one such element, and belongs to the intramembrane-sensing histidine kinase (IM-HK) family, which is conserved within the Firmicutes. The regulators are defined by a small sensing domain within their histidine kinase, suggesting that they do not sense external signals, but stress in or at the membrane. Our characterization of NsaRS in this work reveals …


The Role Of Argininosuccinate Synthase Serine 328 Phosphorylation In Nitric Oxide Production, Ricci Haines Jun 2012

The Role Of Argininosuccinate Synthase Serine 328 Phosphorylation In Nitric Oxide Production, Ricci Haines

USF Tampa Graduate Theses and Dissertations

Until recently, the main mechanism of argininosuccinate synthase (AS) regulation was described to exist mainly at the level of transcription. Transcriptional regulation of AS has been shown to be coordinate with eNOS in response to shear stress, hypoxia, tumor necrosis factor á (TNF-á), and PPAR ã agonist troglitizone. However, it is now understood that one level of NO regulation is cellular control of arginine availability to eNOS via post-translational modifications of AS such as phosphorylation. The purpose of this investigation was to determine under what conditions AS is phosphorylated at S328, identify the pathway that AS phosphorylation at S328 plays …


A Study Of The Eastern Oyster, Crassostrea Virginica, In Tampa Bay: Effects Of Perkinsus Marinus On Reproduction And Condition, Bridgit Melora Mccrickard Jun 2012

A Study Of The Eastern Oyster, Crassostrea Virginica, In Tampa Bay: Effects Of Perkinsus Marinus On Reproduction And Condition, Bridgit Melora Mccrickard

USF Tampa Graduate Theses and Dissertations

Abstract

Five sites in Tampa Bay, Florida, were sampled monthly from February 2006 to January 2007. These sites were located at the mouth of the Alafia River, in an inlet of Cross Bayou, on the easement of Gandy Bridge, near mangrove in Manatee County, and an inlet of Salt Creek, off Bayboro Harbor. Standard methods were used to determine shell height and Condition Index (CI). Intensity and prevalence of Perkinsus marinus were analyzed using Ray's Thioglycollate medium test, while Haplosporidium nelsoni was studied by histological examination. Histological methods were also used to determine sex ratios, reproductive phases, and egg diameters. …


Sigma Factor N (Σn): A Novel Regulator Of Extreme Acid Resistance In Enterohemorrhagic E. Coli O157:H7, Pamela Ann Fay Jun 2012

Sigma Factor N (Σn): A Novel Regulator Of Extreme Acid Resistance In Enterohemorrhagic E. Coli O157:H7, Pamela Ann Fay

USF Tampa Graduate Theses and Dissertations

Extreme acid resistance contributes to the successful transmission of enterohemorrhagic E. coli (EHEC) through acidic food matrices and the stomach, allowing it to gain access to the intestine and elicit disease in humans. Alternative sigma factor N (σN, encoded by rpoN) was previously identified as a novel regulator of extreme acid resistance in EHEC. This study investigated the role for σN and co-expressed products of the rpoN operon in the acid resistance phenotype of EHEC. The results revealed that σN primarily controls acid resistance through repression of the glutamate-dependent acid resistance (GDAR) system through control …


Systematics Of Harrisia (Cactaceae), Alan R. Franck Jun 2012

Systematics Of Harrisia (Cactaceae), Alan R. Franck

USF Tampa Graduate Theses and Dissertations

The genus Harrisia Britton (Cactaceae) comprises species of columnar cacti that are united by a unique seed morphology. The species range in form from prostrate shrubs to large trees and are native to South America and the Caribbean region. Harrisia is placed in an unresolved position within subtribe Trichocereinae of tribe Cereeae of subfamily Cactoideae. Relationships among the species within Harrisia are also poorly understood. In this study, several species of Harrisia were sequenced for as many as seven different regions of nuclear and plastid DNA. Species in the Caribbean were also examined with amplified fragment length polymorphisms. The morphology …


Investigation Into The Mechanism Of Salicylate-Associated Genotypic Antibiotic Resistance In Staphylococcus Aureus, Nada Salah Helal Jun 2012

Investigation Into The Mechanism Of Salicylate-Associated Genotypic Antibiotic Resistance In Staphylococcus Aureus, Nada Salah Helal

USF Tampa Graduate Theses and Dissertations

Growth of Staphylococcus aureus with the NSAID salicylate increases phenotypic resistance (SAPAR), and the frequency at which heritable resistance occurs to various antibiotics (SAGAR). This study describes the effect of salicylate on heritable and phenotypic resistance to a set of antibiotics for laboratory and multi-drug resistant strains of S. aureus and investigates the link between resistance and SAGAR. Drug gradient plates were used to determine phenotypic resistance to antibiotics targeting DNA replication, transcription, translation and the cell wall in the presence or absence of salicylate. To measure heritable resistance, mutation frequencies were determined for each antibiotic in the presence and …


Dissolved Inorganic Carbon Uptake In Thiomicrospira Crunogena Xcl–2 Is Atp–Sensitive And Enhances Rubisco–Mediated Carbon Fixation, Kristy Jae Menning May 2012

Dissolved Inorganic Carbon Uptake In Thiomicrospira Crunogena Xcl–2 Is Atp–Sensitive And Enhances Rubisco–Mediated Carbon Fixation, Kristy Jae Menning

USF Tampa Graduate Theses and Dissertations

Many autotrophic organisms living in environments with episodically low dissolved inorganic carbon (DIC) concentrations compensate for these fluctuations by employing a carbon concentrating mechanism (CCM). By utilizing a CCM, these organisms can generate intracellular DIC concentrations much higher than extracellular, thereby providing sufficient substrate for carbon fixation. Carbon concentrating mechanisms have been well-studied in cyanobacteria but studies are lacking in other autotrophs. The gammaproteobacterium Thiomicrospira crunogena XCL-2 is a hydrothermal vent chemolithoautotroph that has a CCM, which is functionally similar to that of cyanobacteria. At hydrothermal vents, DIC concentrations and pH values fluctuate over time, with CO2 concentrations ranging from …


Biomechanical Testing On Cadaveric Spines For Different Treatments That Affect Lumbar Stability, Sabrina Alejandra Gonzalez Blohm May 2012

Biomechanical Testing On Cadaveric Spines For Different Treatments That Affect Lumbar Stability, Sabrina Alejandra Gonzalez Blohm

USF Tampa Graduate Theses and Dissertations

Stenosis is one of the most common causes for spinal surgery. Laminectomy decompression and fusion are surgical procedures prescribed for this condition. The intention of this work was to investigate the effects of a laminectomy decompression, followed by fusion, on a lumbar functional spinal unit (FSU) through in vitro dynamic (±8Nm at 0.125Hz) and quasi-static (±7.5Nm at 0.1Hz) biomechanical tests, for flexion, extension, bending and rotation motions.

Six FSUs where disarticulated from four human cadaveric lumbar spines (63 ± 12 years) and were tested under the following sequence: (1) intact, (2) laminectomy decompression, and (3) Pedicle Screw System (PSS), using …


The Ecological Role Of Rhizophytic Green Algae In Soft-Bottom Habitats, Laura Bedinger May 2012

The Ecological Role Of Rhizophytic Green Algae In Soft-Bottom Habitats, Laura Bedinger

USF Tampa Graduate Theses and Dissertations

Rhizophytic algae are large, abundant primary producers throughout tropical and subtropical areas worldwide where they grow as an understory in seagrass beds, as well as form mixed or monospecific beds of exclusively rhizophytic algal species. In this dissertation, "rhizophytic algae" refers to coenocytic green algae (Chlorophyta) in the order Bryopsidales that use a net of rhizoids to anchor in unconsolidated sediments. In the development of seagrass beds, rhizophytic algae colonize bare patches and are thought to facilitate seagrass colonization by stabilizing sediments and providing organic matter. However, despite their prominence little is known about many aspects of the ecology of …


The Role Of Hsp70 In Cancer: A Study Of The Hsp70 / Akt Relationship, John Koren Apr 2012

The Role Of Hsp70 In Cancer: A Study Of The Hsp70 / Akt Relationship, John Koren

USF Tampa Graduate Theses and Dissertations

The Hsp70 family of molecular chaperones is essential for

protein folding, re-folding misfolded client proteins, clearance

of aberrant client proteins, and can also inhibit programmed

cell death. There are two major cytosolic members of this

family: the constitutive Hsc70, and the inducible Hsp72. Under

stress conditions the Hsp70 family protects the cell from

protein related damage by the induction of Hsp72. Hsc70 and

Hsp72 are highly homologous with minor differences in

substrate binding. In cancers, Hsp72 is commonly induced and

this induction is thought to aid in cancer cell survival. In these

studies we demonstrate the differential regulation of the …


Paleobiological Assessment Of Controls Underlying Long-Term Diversity Dynamics, Andrés L. Cárdenas Apr 2012

Paleobiological Assessment Of Controls Underlying Long-Term Diversity Dynamics, Andrés L. Cárdenas

USF Tampa Graduate Theses and Dissertations

Deciphering the factors underlying both long-term patterns of diversity and taxonomic turnover rates (i.e., extinction, and origination) has been one of Paleobiology's major foci for the past three decades. The importance of documenting these components is that they will expand our ability to interpret and model the evolutionary processes underlying those trends, highlight the evolutionary impact of historical events, and contribute to the formulation of robust predictions about the future of global diversity in response to the current anthropologically driven environmental changes. Accordingly, the first part of this study examines the possible occurrence of global marine evolutionary environmental controls into …


Fishermen, Politics, And Participation: An Ethnographic Examination Of Commercial Fisheries Management In St. Croix, U.S. Virgin Islands, Cynthia Grace-Mccaskey Apr 2012

Fishermen, Politics, And Participation: An Ethnographic Examination Of Commercial Fisheries Management In St. Croix, U.S. Virgin Islands, Cynthia Grace-Mccaskey

USF Tampa Graduate Theses and Dissertations

Currently, there is widespread debate regarding the overall status of the world's fisheries, with some researchers projecting their total collapse in only a few decades, and others concluding the situation is not quite as bleak. Additional debates include what strategies should be used to manage fisheries at various scales, and further research is needed to determine which strategies are most appropriate for use in particular situations and locales, as context is critical.

Recently, prominent common pool resources scholars have expressed the need for ethnographic approaches to studying resource management institutions in order to move beyond the current focus of simply …


A Spatially Explicit Agent Based Model Of Muscovy Duck Home Range Behavior, James Howard Anderson Apr 2012

A Spatially Explicit Agent Based Model Of Muscovy Duck Home Range Behavior, James Howard Anderson

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Research in GIScience has identified agent-based simulation methodologies as effective in the study of complex adaptive spatial systems (CASS). CASS are characterized by the emergent nature of their spatial expressions and by the changing relationships between their constituent variables and how those variables act on the system's spatial expression over time. Here, emergence refers to a CASS property where small-scale, individual action results in macroscopic or system-level patterns over time. This research develops and executes a spatially-explicit agent based model of Muscovy Duck home range behavior. Muscovy duck home range behavior is regarded as a complex adaptive spatial system …


Enhancing The Immune Response Through Ikkbeta-Induced Activation Of Nf-Kappab, Emily Hopewell Apr 2012

Enhancing The Immune Response Through Ikkbeta-Induced Activation Of Nf-Kappab, Emily Hopewell

USF Tampa Graduate Theses and Dissertations

Nuclear factor-κB (NF-κB) is one of the main regulators of inflammatory and immune responses. It is a family of transcription factors composed of five members: RelA, RelB, cRel, NF-κB1 (p105/p50), and NF-κB2 (p100/p52). Homo- and hetero-dimers of family members are inhibited by inhibitor of &klappaB (IκB) family members and activated by IκB kinase (IKK) family members. The IKK family is comprised of IKKα, IKKΒ, and IKKγ. The focus of my dissertation delves into the role of NF-κB activation by IKKΒ in both an immunotherapy setting and its role in T cell mediated anti-tumor immune responses.

A central focus of immunotherapy …


Protein Profiling Of Adenine Nucleoside And Nucleotide Analogs Binding Proteins Using N6-Biotinylated-8-Azidoadenosine Analogs As Affinity Based Protein Profiling Probes, Shikha Mahajan Apr 2012

Protein Profiling Of Adenine Nucleoside And Nucleotide Analogs Binding Proteins Using N6-Biotinylated-8-Azidoadenosine Analogs As Affinity Based Protein Profiling Probes, Shikha Mahajan

USF Tampa Graduate Theses and Dissertations

Identification of differential expressions of proteins in proteomic profiles of biological samples shows great potential as a valuable technique for the early diagnosis of various diseases. An important challenge in modern protein profiling approaches is to reduce the complexity of the samples by limiting the number of proteins that need to be evaluated for distinction in the expression between normal and deceased cells. In this research, an affinity based approach for the enrichment of nucleotide and nucleoside binding proteins from a complex cell proteome has been developed. To achieve this goal, new N6-biotinylated-8-azido-adenosine probes (AdoRs) have been designed and synthesized …


Regulation Of Natural Killer Cells: Ship-1, 2b4, And Immunomodulation By Lenalidomide, Nicole Renee Fortenbery Apr 2012

Regulation Of Natural Killer Cells: Ship-1, 2b4, And Immunomodulation By Lenalidomide, Nicole Renee Fortenbery

USF Tampa Graduate Theses and Dissertations

Natural Killer cells (NK) are critical components of the innate immune system. Often referred to by their morphology, these large granular lymphocytes (LGLs) are bone marrow-derived lymphocytes and can be found throughout the body. NK cells reside in the liver, lymph nodes, spleen, thymus, and mucosal-associated lymphoid tissues (MALT). Importantly, NK cells also circulate throughout the blood where they function as surveyors of the body and are armed to eliminate malignant, infected, damaged, or foreign cells.

NK cells function by a dual receptor system. That is, NK receptors are broadly categorized as inhibitory or activating. It is a fine balance, …


1-Deoxy-D-Xylulose-5-Phosphate Synthase (Dxs) Mechanistic Study And Its Implication In The Development Of Novel Antibiotics And Antimalarials, Sumit Handa Apr 2012

1-Deoxy-D-Xylulose-5-Phosphate Synthase (Dxs) Mechanistic Study And Its Implication In The Development Of Novel Antibiotics And Antimalarials, Sumit Handa

USF Tampa Graduate Theses and Dissertations

Isoprenoids are the largest family of biologically active compounds, synthesized by five carbon subunits namely isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP). For long time the mevalonate-dependent (MVA) pathway has been considered as the sole source of IPP and DMAPP, until recently a new non-mevalonte dependent (NMVA) pathway was discovered. This new pathway utilizes entirely different set of enzymes for isoprenoids synthesis and don't have any homologues in humans. NMVA pathway is the only source of isoprenoids for certain eubacteria, parasite and plants. Absence of the NMVA pathway in higher organisms has opened a new platform for the development of …


Reproduction And Population Characteristics Of White-Tailed Jackrabbits In South Dakota, Charles Dieter, Dustin Schaible Apr 2012

Reproduction And Population Characteristics Of White-Tailed Jackrabbits In South Dakota, Charles Dieter, Dustin Schaible

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

We evaluated the reproductive biology of314 white-tailed jackrabbits (Lepus townsendii) in 44 counties throughout South Dakota from June 2004 to September 2005. We classified jackrabbits as juveniles or adults based on the closure of the proximal epiphysis of the humerus using X-ray analysis. We determined annual reproductive activity through fluctuations in measured weights of reproductive organs for both sexes. The 2005 breeding season started in late February and proceeded until mid-July, approximately 142 days, allowing for females to potentially produce 3.3 litters. We found four distinct breeding periods by the overlap of estimated conception and parturition dates. Mean …


A Conceptual Model To Facilitate Amphibian Conservation In The Northern Great Plains, David M. Mushet, Ned H. Euliss Jr., Craig A. Stockwell Apr 2012

A Conceptual Model To Facilitate Amphibian Conservation In The Northern Great Plains, David M. Mushet, Ned H. Euliss Jr., Craig A. Stockwell

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

As pressures on agricultural landscapes to meet worldwide resource needs increase, amphibian populations face numerous threats including habitat destruction, chemical contaminants, disease outbreaks, wetland sedimentation, and synergistic effects of these perturbations. To facilitate conservation planning, we developed a conceptual model depicting elements critical for amphibian conservation in the northern Great Plains. First, we linked upland, wetland, and landscape features to specific ecological attributes. Ecological attributes included adult survival; reproduction and survival to metamorphosis; and successful dispersal and recolonization. Second, we linked ecosystem drivers, ecosystem stressors, and ecological effects of the region to each ecological attribute. Lastly, we summarized information on …


Parochlus Kiefferi (Garrett, 1925) In Nebraska (Diptera: Chironomidae), Barbara Hayford Apr 2012

Parochlus Kiefferi (Garrett, 1925) In Nebraska (Diptera: Chironomidae), Barbara Hayford

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

A rare species of nonbiting aquatic midge, Parochlus kiefferi (Garrett, 1925), was discovered in Squaw Creek in the Pine Ridge of northwest Nebraska. Parochlus is a genus of midge found throughout the Southern Hemisphere and is only represented by this one species in the Northern Hemisphere. The typical North American species distribution of P. kiefferi includes high alpine and northern latitude streams, so the collection of P. kiefferi from a low elevation and low-latitude stream in Nebraska represents a range extension for the species. A survey for P. kiefferi from 83 samples from 53 stream sites in northern Nebraska yielded …


Adaptation Of Annual Forage Legumes In The Southern Great Plains, John A. Guretzky, Twain J. Butler, Jim P. Muir Apr 2012

Adaptation Of Annual Forage Legumes In The Southern Great Plains, John A. Guretzky, Twain J. Butler, Jim P. Muir

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Our objective was to evaluate adaptation and compatibility of cool-season annual legumes overseeded into perennial grasses in the southern Great Plains. Freeze damage, vigor, and standing crop of 14 annual legume species were evaluated during spring at three locations in Oklahoma and Texas from 2006 to 2008. Across locations and years, standing crop of hairy vetch (Vicia villosa Roth) and Austrian winter pea (Pisum sativum L. ssp. arvense (L.) Poir.] averaged 3,513 and 3,210 kg dry matter (DM) ha-1, respectively. Standing crop of crimson clover (Trifolium incarnatum L.) and arrowleaf clover (T. vesiculosum Savi) averaged …