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Full-Text Articles in Life Sciences

Recent Decline Of Lowland Populations Of The Western Gray Squirrel In The Los Angeles Area Of Southern California, Daniel S. Cooper, Alan Muchlinski Jul 2105

Recent Decline Of Lowland Populations Of The Western Gray Squirrel In The Los Angeles Area Of Southern California, Daniel S. Cooper, Alan Muchlinski

Bulletin of the Southern California Academy of Sciences

We provide an overview of the distribution of lowland and otherwise isolated populations of the western gray squirrel (Sciurus griseus) in the Los Angeles area of southern California, an area that has experienced a recent and ongoing invasion by the non-native eastern fox squirrel (Sciurus niger), an urban-adapted species introduced a century ago. Away from its strongholds in the western Santa Monica Mountains, San Gabriel Mountains, and Santa Ana Mountains, the western gray squirrel is resident locally in both the Santa Susana and the Verdugo Mountains, in Griffith Park, in low hills at the eastern periphery of the San Gabriel ...


An Orange Fluorescent Protein Tagging System For Real-Time Pollen Tracking, J. Rice, R. Mundell, R. Millwood, O. Chambers, L. Abercrombie, H. Davies, C. Stewart Dec 2102

An Orange Fluorescent Protein Tagging System For Real-Time Pollen Tracking, J. Rice, R. Mundell, R. Millwood, O. Chambers, L. Abercrombie, H. Davies, C. Stewart

C. Neal Stewart Jr.

Background Monitoring gene flow could be important for future transgenic crops, such as those producing plant-made-pharmaceuticals (PMPs) in open field production. A Nicotiana hybrid (Nicotiana. tabacum × Nicotiana glauca) shows limited male fertility and could be used as a bioconfined PMP platform. Effective assessment of gene flow from these plants is augmented with methods that utilize fluorescent proteins for transgenic pollen identification. Results We report the generation of a pollen tagging system utilizing an orange fluorescent protein to monitor pollen flow and as a visual assessment of transgene zygosity of the parent plant. This system was created to generate a tagged ...


Effect Of External Energy On The Atomic, Crystalline, And Powder Characteristics Of Antimony And Bismuth Powders, Mahendra Kumar Trivedi Sep 2099

Effect Of External Energy On The Atomic, Crystalline, And Powder Characteristics Of Antimony And Bismuth Powders, Mahendra Kumar Trivedi

Mahendra Kumar Trivedi

Next to atoms and molecules the powders are the smallest state of matter available in high purities and large quantities. The effect of any external energy on the shape, morphology and structure can thus be studied with relative ease. The present investigation deals with the effect of a non-contact external energy on the powders of antimony and bismuth. The characteristics of powders treated by external energy are compared with the as received powders (control). The average particle sizes, d50 and d99, the sizes below which 99% of the particles are present showed significant increase and decrease indicating that the energy ...


Potential For Climate Induced Methane Hydrate Dissociation, Graham Macwilliams Jan 2018

Potential For Climate Induced Methane Hydrate Dissociation, Graham Macwilliams

Pomona Senior Theses

Methane hydrates are frozen deposits of methane and water found in high pressure or low temperature sediments. When these deposits destabilize, large quantities of methane can be emitted into the atmosphere. This is significant to climate change because methane has 25 times more greenhouse gas potential than Carbon Dioxide. Worldwide, it is estimated there are between 2500 and 10000 gigatons of methane stored in hydrate deposits. This represents more carbon than all fossil fuels on Earth. It is estimated that between 200 and 2000 gigatons of methane are stored in hydrates in Arctic waters acutely vulnerable to greenhouse warming. Over ...


Tea Induction Of Cyp6a8 Promoter In Drosophila Melanogaster, Fiona Retzer Dec 2017

Tea Induction Of Cyp6a8 Promoter In Drosophila Melanogaster, Fiona Retzer

University of Tennessee Honors Thesis Projects

No abstract provided.


Superresolution Imaging Identifies That Conventional Trafficking Pathways Are Not Essential For Endoplasmic Reticulum To Outer Mitochondrial Membrane Protein Transport., Kyle Salka, Shivaprasad Bhuvanendran, Kassandra Wilson, Petros Bozidis, Mansi Mehta, Kristin Rainey, Hiromi Sesaki, George H Patterson, Jyoti K. Jaiswal, Anamaris M. Colberg-Poley Dec 2017

Superresolution Imaging Identifies That Conventional Trafficking Pathways Are Not Essential For Endoplasmic Reticulum To Outer Mitochondrial Membrane Protein Transport., Kyle Salka, Shivaprasad Bhuvanendran, Kassandra Wilson, Petros Bozidis, Mansi Mehta, Kristin Rainey, Hiromi Sesaki, George H Patterson, Jyoti K. Jaiswal, Anamaris M. Colberg-Poley

Integrative Systems Biology Faculty Publications

Most nuclear-encoded mitochondrial proteins traffic from the cytosol to mitochondria. Some of these proteins localize at mitochondria-associated membranes (MAM), where mitochondria are closely apposed with the endoplasmic reticulum (ER). We have previously shown that the human cytomegalovirus signal-anchored protein known as viral mitochondria-localized inhibitor of apoptosis (vMIA) traffics from the ER to mitochondria and clusters at the outer mitochondrial membrane (OMM). Here, we have examined the host pathways by which vMIA traffics from the ER to mitochondria and clusters at the OMM. By disruption of phosphofurin acidic cluster sorting protein 2 (PACS-2), mitofusins (Mfn1/2), and dynamin related protein 1 ...


J. C. Penney: The Man, The Store And American Agriculture (Under Contract), David Delbert Kruger May 2017

J. C. Penney: The Man, The Store And American Agriculture (Under Contract), David Delbert Kruger

David Delbert Kruger

No abstract provided.


Does Personality Similarity In Bottlenose Dolphin Pairs Influence Dyadic Bond Characteristics?, Kelsey R. Moreno May 2017

Does Personality Similarity In Bottlenose Dolphin Pairs Influence Dyadic Bond Characteristics?, Kelsey R. Moreno

Master's Theses

Social structures are critical to the success of many species and have repercussions on health, well-being, and adaptation, yet little is known about the factors which shape these structures aside from ecology and life history strategies. Dyadic bonds are the basis of all social structures; however, mechanisms for formations of specific bonds or patterns in which individuals form which types of bonds have yet to be demonstrated. There is a variety of evidence indicating personality may be a factor in shaping bonds, but this relationship has not been explored with respect to bond components and is yet to be demonstrated ...


Do Pinnipeds Have Personality? Coding Harbor Seal (Phoca Vitulina) And California Sea Lion (Zalophus Californianus) Behavior Across Contexts., Amber J. De Vere May 2017

Do Pinnipeds Have Personality? Coding Harbor Seal (Phoca Vitulina) And California Sea Lion (Zalophus Californianus) Behavior Across Contexts., Amber J. De Vere

Master's Theses

Personality has now been studied in species as diverse as chimpanzees (King & Figueredo, 1997) and cuttlefish (Carere et al., 2015), but marine mammals remain vastly underrepresented in this area. A broad range of traits have been assessed only in the bottlenose dolphin (Highfilll & Kuczaj, 2007), while consistent individual differences in a few specific behaviors have been identified in grey seals (Robinson et al., 2015; Twiss & Franklin, 2010; Twiss, Culloch & Pomeroy, 2011; Twiss, Cairns, Culloch, Richards & Pomeroy, 2012). Furthermore, the context component of definitions of personality is not often assessed, despite evidence that animals may show individual patterns of consistency (Kuczaj, Highfill & Byerly, 2012). The current study therefore aimed to assess underlying personality factors and consistency across contexts in two unstudied marine mammal species, using behavioral coding.

Two California sea lion and three harbor seal personality factors were extracted using exploratory factor analysis. Two factors were broadly similar across species; the first, Boldness, resembled human Extraversion, and to some extent Openness. The second factor was labeled Routine Activity, and contained some Conscientiousness-like traits. Excitable-Interest emerged as a third factor in seals, but had low reliability. Species-specific patterns were also identified for interactive behaviors across two contexts. However, there was substantial individual variation in the frequency of these behaviors, as well as some animals who did not conform to species-level trends. This study therefore provides novel evidence for broad personality factors and ...


Heterogeneity Of Avian Breeding Habitat On Grazing Lands Of The Northern Great Plains, Maggi S. Sliwinski May 2017

Heterogeneity Of Avian Breeding Habitat On Grazing Lands Of The Northern Great Plains, Maggi S. Sliwinski

Dissertations & Theses in Natural Resources

Native rangelands in the Great Plains are largely privately owned and used for beef production. Vegetation heterogeneity is important for maintaining biodiversity, but private land may be more homogenous than desired. My research had two components: 1) to examine whether a variety of grazing strategies created vegetation heterogeneity in a large, intact rangeland, and 2) to understand beef producers’ attitudes about vegetation heterogeneity.

First, I sampled vegetation structure, composition, and bird abundance at multiple plots on eleven management units in Cherry County, Nebraska. Units were managed with commonly used grazing strategies (e.g., short-duration grazing and season-long continuous grazing). I ...


From Disaster To Sustainability: The Story Of The Pacific Groundfish, Matthew Richards May 2017

From Disaster To Sustainability: The Story Of The Pacific Groundfish, Matthew Richards

All Graduate Plan B and other Reports

This paper reviews the circumstances that led to the collapse of the Pacific groundfish fishery and the steps that fishery managers took to curb over-harvesting and bring the fishery back to sustainability. Fishery managers utilized various management tools such as a vessel buyback program, regulatory mechanisms, and market strategies to improve the available data on the fishery, improve safety for fishermen, and reduce harvest rates and overcapitalization. By employing a diverse range of measures, managers developed a system by with they successfully balanced conservation objectives and minimized adverse impacts to fishing communities. Overcapitalization and overharvest continue to degrade the health ...


Sparking A Dolphin's Curiosity: Individual Differences In Dolphins' Reactions To Surprising And Expectation-Violating Events, Malin Katarina Lilley May 2017

Sparking A Dolphin's Curiosity: Individual Differences In Dolphins' Reactions To Surprising And Expectation-Violating Events, Malin Katarina Lilley

Master's Theses

Non-scientific literature consistently describes dolphins as “curious animals,” but there has been little systematic research on curiosity in dolphins. Curiosity in humans and certain non-human animal species, including birds and non-human primates, has been studied by examining individual differences in exploration and reactions to novel stimuli. Additionally, research has explored how human infants and non-human animals react when an event violates their expectations. The present study explored dolphins’ reactions to spontaneously surprising and expectation-violating stimuli. The reactions of dolphins, 15 bottlenose (Tursiops truncatus) and 6 rough-toothed (Steno bredanensis), at Gulf World Marine Park were analyzed in response to events that ...


White-Ch6-Groundingreligion2.Pdf, Carol W. White Apr 2017

White-Ch6-Groundingreligion2.Pdf, Carol W. White

Carol White


One effective way of addressing race and ethnicity within the paradigm of ecology and religion is through the lens of religious naturalism. Religious naturalism shifts our thinking back to ourselves as natural processes, encouraging us to question our values, behaviors, and resource uses as we conceive and enact our relationalitywith each other and the more-than-human worlds.
 
I first describe the presence of white supremacy in United States to help contextualize historical and current problems related to race and ethnicity in ecological movements, as well as the lack of full religious reflection and problematic responses to them. I also discuss key ...


Stem Cell Derived Osteoprogenitors And Their Role In Bone Repair Using Morphogenic Activators, Angelina Miller, Sylvanna Islas, George Washington Brownridge Iii, Warren Hoeffler Apr 2017

Stem Cell Derived Osteoprogenitors And Their Role In Bone Repair Using Morphogenic Activators, Angelina Miller, Sylvanna Islas, George Washington Brownridge Iii, Warren Hoeffler

Scholarly & Creative Works Conference 2017

Bone constantly cycles through a dynamic process of breakdown and remodeling. Osteoblasts are the specialized mesenchymal stem cells that have a major role in bone formation and the remodeling process whereas their counterpart osteoclasts, handle bone resorption. Embryonic stem cells can be partially differentiated into Progenitor cells, and we worked with #18, a candidate for being an osteoprogenitor that has the potential to respond to morphogenic activators. In the case of bone remodeling, TGF-β 2, BMP-2 and an abundance of CA++ have been shown to be potential activators of differentiation into osteoblasts. Eight different trials were conducted with the cells ...


Spinal Cord Injuries And Evaluation Of Treatments, Amanda Nelson Apr 2017

Spinal Cord Injuries And Evaluation Of Treatments, Amanda Nelson

Biology: Student Scholarship & Creative Works

Spinal cord injuries (SCI) are common injuries that do not currently have a fully successful treatment. These injuries cause many physical, psychological, and social burdens for the injured person and any close friends or family members. Older treatment options include surgery, pharmacotherapy, and physical therapy, while newer treatment options include stem cell therapy, bionics, and electrical stimulation. After a full evaluation of the treatments, it was concluded that the best treatment for today is pharmacotherapy, but with more research, stem cell therapy will become the ideal treatment for SCI in the future.


Eassistant: Cognitive Assistance For Identification And Auto-Triage Of Actionable Conversations, Hamid R. Motahari Nezhad, Kalpa Gunaratna, Juan Cappi Apr 2017

Eassistant: Cognitive Assistance For Identification And Auto-Triage Of Actionable Conversations, Hamid R. Motahari Nezhad, Kalpa Gunaratna, Juan Cappi

Kno.e.sis Publications

The browser and screen have been the main user interfaces of the Web and mobile apps. The notification mechanism is an evolution in the user interaction paradigm by keeping users updated without checking applications. Conversational agents are posed to be the next revolution in user interaction paradigms. However, without intelligence on the triage of content served by the interaction and content differentiation in applications, interaction paradigms may still place the burden of information overload on users. In this paper, we focus on the problem of intelligent identification of actionable information in the content served by applications, and in particular in ...


The Behavior And Ecology Of Cursorial Predators And Dangerous Prey: Integrating Behavioral Mechanisms With Population-Level Patterns In Large Mammal Systems, Aimee Tallian Apr 2017

The Behavior And Ecology Of Cursorial Predators And Dangerous Prey: Integrating Behavioral Mechanisms With Population-Level Patterns In Large Mammal Systems, Aimee Tallian

All Graduate Theses and Dissertations

Driving into Yellowstone National Park for the first time is a moving experience. Gazing over the sweeping landscapes, seeing a geyser erupt 80 feet into the air, and having your first ‘wildlife encounter’, whether that be a 2 ton bull bison aggressively wallowing on his dirt mound, snorting and kicking up dust, or watching a pack of 6 wolves move through a valley off in the distance, pausing to howl in search of their companions. Yellowstone staff wishes to manage our park in a way that preserves these remarkable experiences. In order to effectively manage this dynamic ecosystem, it is ...


Precision Drought Stress In Orchards: Rootstock Evaluation, Trunk Hydration And Canopy Temperature, Lance V. Scott Apr 2017

Precision Drought Stress In Orchards: Rootstock Evaluation, Trunk Hydration And Canopy Temperature, Lance V. Scott

All Graduate Theses and Dissertations

In many areas, over half of all diverted water is used for irrigation. Tree fruit crops use a lot of water, but water productivity can be increased using properly-timed precision water stress. In addition to water conservation, increases in water productivity arise from better fruit quality, increased storage life and reductions in pruning and maintenance. One major hurdle to applying precision water stress in orchards is the lack of a reliable, automated method of determining tree water status. However, the influence of physiological characteristics such as rootstock vigor on water productivity are also important. Selecting the most appropriate rootstocks and ...


Effects Of Gestational Dietary Intake On Calf Growth And Early Feedlot Performance Of Offspring, Jose Gardner Apr 2017

Effects Of Gestational Dietary Intake On Calf Growth And Early Feedlot Performance Of Offspring, Jose Gardner

All Graduate Theses and Dissertations

Fetal programming is a relatively new and quickly growing field of research in the livestock industry. The concept of fetal programming is simply defined as the effects a change in maternal nutritional intake has on offspring, whether it be a genetic or physical change. The intention of this study was to specifically look at the effects of nutrient restriction of cows during the second trimester of gestation on the growth and performance of the resulting calves.

In this study, thirty-two cows of predominantly angus influence from the Utah state university herd were chosen, naturally bred to a pure bred angus ...


Intentional Mentoring Through 4-H: The Role Of 4-H In A Successful Mentoring Program Between Youth And Adults, Emily Ann Shepperd Apr 2017

Intentional Mentoring Through 4-H: The Role Of 4-H In A Successful Mentoring Program Between Youth And Adults, Emily Ann Shepperd

All Graduate Theses and Dissertations

4-H Youth and Families with Promise (4-H YFP) is a one to one youth mentoring program that aims to help youth obtain skills that will help them to be successful. The purpose of this research was to determine if any positive outcomes were shown of youth participating in 4-H YFP. Positive outcomes were identified as peer social competence, greater ability to make positive choices, the development of effective communication skills, building connections, and contributing to the community. Results show that these outcomes positively increased among youth participants in the 4-H YFP program- but the changes were too small to be ...


Seasonal And Rotational Influences On Corn Nitrogen Fertilization In Southwest Iowa, John Sawyer, Daniel Barker Mar 2017

Seasonal And Rotational Influences On Corn Nitrogen Fertilization In Southwest Iowa, John Sawyer, Daniel Barker

John E. Sawyer

This project was designed to study the nitrogen (N) fertilization needs in continuous corn (CC) and corn rotated with soybean (CS) as influenced by location and climate. Multiple rates of fertilizer N were spring applied, with the intent to measure yield response to N within each rotation on a yearly basis for multiple years at multiple sites across Iowa. This will allow determination of N requirements for each rotation, differences that exist between the two rotations, responses to applied N across different soils and climatic conditions, and evaluation of tools used to adjust N application.


Corn Yield Response To Nitrogen Fertilizer Application Timing In Northeast Iowa, John Lundvall, Dan Barker, John Sawyer Mar 2017

Corn Yield Response To Nitrogen Fertilizer Application Timing In Northeast Iowa, John Lundvall, Dan Barker, John Sawyer

John E. Sawyer

The objective of this project was to measure corn yield response to fertilizer nitrogen (N) application timing (spring pre-plant or at-planting vs. split/side-dress) across multiple N rates (0 to 250 lb total-N/acre). Results were determined through fitting yield response to N-rate regression equations and calculation of economic optimum nitrogen rate (EONR) based on a 0.10 N fertilizer price-to-corn price ratio.


Corn Yield Response To Nitrogen Fertilizer Application Timing In Southwest Iowa, John Lundvall, Dan Barker, John Sawyer Mar 2017

Corn Yield Response To Nitrogen Fertilizer Application Timing In Southwest Iowa, John Lundvall, Dan Barker, John Sawyer

John E. Sawyer

The objective of this project was to measure corn yield response to fertilizer nitrogen (N) application timing (spring pre-plant or at-planting vs. split/side-dress) across multiple N rates (0 to 250 lb total-N/acre). Results were determined through fitting yield response to N-rate regression equations and calculation of economic optimum nitrogen rate (EONR) based on a 0.10 N fertilizer price-to-corn price ratio.


Enhancing Corn Yield In A Winter Cereal Rye Cover Crop System In Northeast Iowa, John Lundvall, Swetabh Patel, John Sawyer Mar 2017

Enhancing Corn Yield In A Winter Cereal Rye Cover Crop System In Northeast Iowa, John Lundvall, Swetabh Patel, John Sawyer

John E. Sawyer

Water quality impairment related to nitrogen (N) is a concern in Iowa, including meeting nitrate (NO3) drinking water standards and reducing the amount of N lost to the Gulf of Mexico. The Iowa Nutrient Reduction Strategy science assessment identified a rye cover crop as an important in-field management practice for reducing N and phosphorus (P) loss from fields (31% NO3-N and 29% P), and for reducing soil erosion. However, the science assessment identified a corn yield reduction of 6 percent when grown following a rye cover crop. Lower corn yield with use of a cover crop is unacceptable to farmers ...


Enhancing Corn Yield In A Winter Cereal Rye Cover Crop System In Southwest Iowa, John Lundvall, Swetabh Patel, John Sawyer Mar 2017

Enhancing Corn Yield In A Winter Cereal Rye Cover Crop System In Southwest Iowa, John Lundvall, Swetabh Patel, John Sawyer

John E. Sawyer

Water quality impairment related to nitrogen (N) is a concern in Iowa, including meeting nitrate (NO3) drinking water standards and reducing the amount of N lost to the Gulf of Mexico. The Iowa Nutrient Reduction Strategy science assessment identified a rye cover crop as an important in-field management practice for reducing N and phosphorus (P) loss from fields (31% NO3-N and 29% P), and for reducing soil erosion. However, the science assessment identified a corn yield reduction of 6 percent when grown following a rye cover crop. Lower corn yield with use of a cover crop is unacceptable to farmers ...


Impact Of 4r Management On Crop Production And Nitrate-Nitrogen Loss In Tile Drainage, Matthew Helmers, John Sawyer, Carl Pederson Mar 2017

Impact Of 4r Management On Crop Production And Nitrate-Nitrogen Loss In Tile Drainage, Matthew Helmers, John Sawyer, Carl Pederson

John E. Sawyer

Corn Belt corn and soybean producers are increasingly challenged to maximize crop production while addressing the contributions farm practices make to Gulf hypoxia. Based on the need for nitrate-N reductions in surface water systems to meet water quality goals, new management practices are needed to reduce nitrate-N losses at minimal cost and maximum economic benefits. This three-year field research and demonstration project is evaluating various promising N management methods and technologies by documenting the nitrate-N export and crop yield from various systems.


Enhancing Corn Yield In A Winter Cereal Rye Cover Crop System In Southeast Iowa, John Lundvall, Swetabh Patel, John Sawyer Mar 2017

Enhancing Corn Yield In A Winter Cereal Rye Cover Crop System In Southeast Iowa, John Lundvall, Swetabh Patel, John Sawyer

John E. Sawyer

Water quality impairment related to nitrogen (N) is a concern in Iowa, including meeting nitrate (NO3) drinking water standards and reducing the amount of N lost to the Gulf of Mexico. The Iowa Nutrient Reduction Strategy science assessment identified a rye cover crop as an important in-field management practice for reducing N and phosphorus (P) loss from fields (31% NO3-N and 29% P), and for reducing soil erosion. However, the science assessment identified a corn yield reduction of 6 percent when grown following a rye cover crop. Lower corn yield with use of a cover crop is unacceptable to farmers ...


Seasonal And Rotational Influences On Corn Nitrogen Fertilization In Northeast Iowa, John Sawyer, Daniell Barker Mar 2017

Seasonal And Rotational Influences On Corn Nitrogen Fertilization In Northeast Iowa, John Sawyer, Daniell Barker

John E. Sawyer

This project was designed to study the N fertilization needs in continuous corn (CC) and corn rotated with soybean (CS) as influenced by location and climate. Multiple rates of fertilizer N were spring applied, with the intent to measure yield response to N within each rotation on a yearly basis for multiple years at multiple sites across Iowa. This will allow determination of N requirements for each rotation, differences that exist between the two rotations, responses to applied N across different soils and climatic conditions, and evaluation of tools used to adjust N application.


Enhancing Corn Yield In A Winter Cereal Rye Cover Crop System In Northwest Iowa, John Lundvall, Swetabh Patel, John Sawyer Mar 2017

Enhancing Corn Yield In A Winter Cereal Rye Cover Crop System In Northwest Iowa, John Lundvall, Swetabh Patel, John Sawyer

John E. Sawyer

Water quality impairment related to nitrogen (N) is a concern in Iowa, including meeting nitrate (NO3) drinking water standards and reducing the amount of N lost to the Gulf of Mexico. The Iowa Nutrient Reduction Strategy science assessment identified a rye cover crop as an important in-field management practice for reducing N and phosphorus (P) loss from fields (31% NO3-N and 29% P), and for reducing soil erosion. However, the science assessment identified a corn yield reduction of 6 percent when grown following a rye cover crop. Lower corn yield with use of a cover crop is unacceptable to farmers ...


Seasonal And Rotational Influences On Corn Nitrogen Fertilization In Northwest Iowa, John Sawyer, Daniel Barker Mar 2017

Seasonal And Rotational Influences On Corn Nitrogen Fertilization In Northwest Iowa, John Sawyer, Daniel Barker

John E. Sawyer

This project was designed to study the N fertilization needs in continuous corn (CC) and corn rotated with soybean (SC) as influenced by location and climate. Multiple rates of fertilizer N were spring applied, with the intent to measure yield response to N within each rotation on a yearly basis for multiple years at multiple sites across Iowa. This will allow determination of N requirements for each rotation, differences that exist between the two rotations, responses to applied N across different soils and climatic conditions, and evaluation of tools used to adjust N application.