Life Sciences Commons^™

Water Productivity Of Rainfed Maize And Wheat: A Local To Global Perspective, Juan I. Rattalino Edreira, Nicolas Guilpart, Victor Sadras, Kenneth G. Cassman, Martin K. Van Ittersum, Rene L.M. Schils, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Water productivity (WP) is a robust benchmark for crop production in relation to available water supply across spatial scales. Quantifying water-limited potential (WPw) and actual on-farm (WPa) WP to estimate WP gaps is an essential first step to identify the most sensitive factors influencing production capacity with limited water supply. This study combines local weather, soil, and agronomic data, and crop modeling in a spatial framework to determine WPw and WPa at local and regional levels for rainfed cropping systems in 17 (maize) and 18 (wheat) major grain-producing countries representing a wide range of cropping systems, from intensive, highyield maize …

Optogenetic Examination Of Salt Taste In Mice, Martin Raymond

Master's Theses and Doctoral Dissertations

This thesis describes a series of experiments designed to evaluate the hypothesis that Type I taste receptor cells play a critical role in the detection and transduction of sodium taste via of epithelial sodium channels (ENaCs). Experiment 1 validated the function of a simple and affordable behavioral apparatus (hardware and software) for testing taste preference and taste aversion in mice. Experiment 2 demonstrated a pharmacological method for rapid induction of salt appetite in mice. Experiment 3 showed that optogenetic stimulation of Type I taste receptor cells (TRCs) in transgenic mice could drive consumption of tap water under conditions of salt …

Epigenomic Plasticity Of Arabidopsis Msh1 Mutants Under Prolonged Cold Stress, Sunil Kumar Kenchanmane Raju, Mon-Ray Shao, Yashitola Wamboldt, Sally A. Mackenzie

Department of Agronomy and Horticulture: Faculty Publications

Dynamic transcriptional and epigenetic changes enable rapid adaptive benefit to environmental fluctuations. However, the underlying mechanisms and the extent to which this occurs are not well known. MutS Homolog 1 (MSH1) mutants cause heritable developmental phenotypes accompanied by modulation of defense, phytohormone, stress‐response, and circadian rhythm genes, as well as heritable changes in DNA methylation patterns. Consistent with gene expression changes, msh1 mutants display enhanced tolerance for abiotic stress including drought and salt stress, while showing increased susceptibility to freezing temperatures. Despite changes in defense and biotic stress‐response genes, msh1 mutants showed increasing susceptibility to the bacterial pathogen Pseudomonas syringae. …

Nocturnally-Migrating Birds Traverse Earth's Most Light-Polluted Regions, And Bright Lights Confound Their Habitat Use En Route, Jeffrey J. Butler, James D. Mclaren, Sergio A. Cabrera-Cruz, Jaclyn A. Smolinsky, Timothy D. Schreckengost, Matthew E. Boone, E. Emiel Van Loon, Deanna K. Dawson, Eric L. Walters

Biological Sciences Faculty Publications

No abstract provided.

Towards Understanding The Role Of Small Mammals In The Transmission Of Lyme Disease In Virginia, Usa, Robert K. Rose, Laura Bitzer, Wayne Hynes, Holly D. Gaff, Robyn Nadolny, Jory Brinkerhoff

Biological Sciences Faculty Publications

Larvae and nymphs of many species of ticks select small mammals, reptiles, and birds as hosts. Since 2011, we have examined more than 1,000 small mammals of 10 species and collected a small tissue sample as well as all visible ticks; rates of infestation range from 18% in harvest mice to 53% in meadow voles. Identification of immature ticks is challenging and requires molecular or genetic methods beyond classification as being from the genus Ixodes or another genus. Ixodes ticks include Ixodes scapularis, the species that transmits the Lyme disease-causing bacterium Borrelia burgdorferi to humans. Of the approximately 2,300 ticks …

Energy-Rich Mesopelagic Fishes Revealed As A Critical Prey Resource For A Deep-Diving Predator Using Quantitative Fatty Acid Signature Analysis, Chandra Goetsch, Melinda G. Conners, Suzanne M. Budge, Yoko Mitani, William A. Walker, Jeffrey F. Bromaghin, Samantha E. Simmons, Colleen Reichmuth, Daniel P. Costa

Biological Sciences Faculty Publications

Understanding the diet of deep-diving predators can provide essential insight to the trophic structure of the mesopelagic ecosystem. Comprehensive population-level diet estimates are exceptionally difficult to obtain for elusive marine predators due to the logistical challenges involved in observing their feeding behavior and collecting samples for traditional stomach content or fecal analyses. We used quantitative fatty acid signature analysis (QFASA) to estimate the diet composition of a wide-ranging mesopelagic predator, the northern elephant seal (Mirounga angustirostris), across five years. To implement QFASA, we first compiled a library of prey fatty acid (FA) profiles from the mesopelagic eastern North Pacific. Given …

Interesting, Provocative, And Enigmatic: Morphological Observations On Southeastern Quillworts (Isoetes Isoetaceae, Lycopodiophyta, Rebecca D. Bray, Peter W. Schafran, Lytton J. Musselman

Biological Sciences Faculty Publications

The unique morphology of quillworts has received limited attention, and such studies have been limited to only a few species. Our extensive field work during the past two decades has revealed variation in the structures of the plant, including the rhizomorph, scales, phyllopodia, and abscission caps. Polarity of the axes of southeastern quillwort rhizomorphs varies from discoid (most species), to elongate, to upright with axis branching in several species. In species of intermittent streams, these branched rhizomorphs produce plantlets that break off in running water. Scales are tiny brown or black structures in alternating whorls with sporophylls (leaves). They are …

Better Living Through Chemistry: Addressing Emerging Antibiotic Resistance, Nathan P. Coussens, Ashley L. Molinaro, Kayla J. Culbertson, Tyler Peryea, Gergely Zahoránszky-Köhalmi, Matthew D. Hall, Dayle A. Daines

Biological Sciences Faculty Publications

The increasing emergence of multidrug-resistant bacteria is recognized as a major threat to human health worldwide. While the use of small molecule antibiotics has enabled many modern medical advances, it has also facilitated the development of resistant organisms. This minireview provides an overview of current small molecule drugs approved by the US Food and Drug Administration (FDA) for use in humans, the unintended consequences of antibiotic use, and the mechanisms that underlie the development of drug resistance. Promising new approaches and strategies to counter antibiotic-resistant bacteria with small molecules are highlighted. However, continued public investment in this area is critical …

Range Expansion Of Tick Disease Vectors In North America: Implications For Spread Of Tick-Borne Disease, Daniel E. Sonenshine

Biological Sciences Faculty Publications

Ticks are the major vectors of most disease-causing agents to humans, companion animals and wildlife. Moreover, ticks transmit a greater variety of pathogenic agents than any other blood-feeding arthropod. Ticks have been expanding their geographic ranges in recent decades largely due to climate change. Furthermore, tick populations in many areas of their past and even newly established localities have increased in abundance. These dynamic changes present new and increasing severe public health threats to humans, livestock and companion animals in areas where they were previously unknown or were considered to be of minor importance. Here in this review, the geographic …

Adiposity And Fat Metabolism During Combined Fasting And Lactation In Elephant Seals, Melinda Fowler, Cory Champagne, Daniel Croker

Biological Sciences Faculty Publications

Animals that fast depend on mobilizing lipid stores to power metabolism. Northern elephant seals (Mirounga angustirostris) incorporate extended fasting into several life-history stages: development, molting, breeding and lactation. The physiological processes enabling fasting and lactation are important in the context of the ecology and life history of elephant seals. The rare combination of fasting and lactation depends on the efficient mobilization of lipid from adipose stores and its direction into milk production. The mother elephant seal must ration her finite body stores to power maintenance metabolism, as well as to produce large quantities of lipid and protein rich …

Do Avian Blood Parasites Influence Hypoxia Physiology In A High Elevation Environment?, Farah Ishtiaq, Sahas Barve

Biological Sciences Faculty Publications

BACKGROUND: Montane birds which engage in elevational movements have evolved to cope with fluctuations in environmental hypoxia, through changes in physiological parameters associated with blood oxygen-carrying capacity such as haemoglobin concentration (Hb) and haematocrit (Hct). In particular, elevational migrants which winter at low elevations, encounter varying intensities of avian haemosporidian parasites as they traverse heterogeneous environments. Whilst high intensity parasite infections lead to anaemia, one can expect that the ability to cope with haemosporidian infections should be a key trait for elevational migrants that must be balanced against reducing the oxygen-carrying capacity of blood in response to high elevation. In …

Review: Application Of Tick Control Technologies For Blacklegged, Lone Star, And American Dog Ticks, Alexis White, Holly Gaff

Biological Sciences Faculty Publications

Tick population control technologies have been studied for several decades but no method is successful in all situations. The success of each technology depends on tick species identity and abundance, host species identity and abundance, phenology of both ticks and hosts, geographic region, and a multitude of other factors. Here we review current technologies, presenting an overview of each and its effect on three common tick species in the eastern United States: blacklegged ticks (Ixodes scapularis (Say; Ixodida: Ixodidae)), lone star ticks (Amblyomma americanum (Linnaeus; Ixodida: Ixodidae)), and American dog ticks (Dermacentor variabilis (Say; Ixodida: Ixodidae)). Moreover, …

The Spatial Context Of “Winning” In Mpa Network Design: Location Matters, Andrew S. Kough, Claire B. Paris, Mark J. Butler Iv

Biological Sciences Faculty Publications

(First paragraph) Chollett et al. (2017) make the case that a local network of marine protected areas (MPAs) enhances fisheries for Caribbean spiny lobster (Panulirus argus) off the coast of Honduras. However, their simulation focused on one ecoregion where self-recruitment is predicted to be among the highest in the Caribbean (Cowen, Paris, & Srinivasan, 2006). The shallow banks and scattered cays of the Honduran-Nicaraguan Rise, separating the Cayman and Colombian basins, create an obstacle to the powerful southern Caribbean jet (Richardson, 2005), fostering an ideal location for topographically steered eddies and larval retention. Local management,whether based on traditional …

Muscle Activation Analysis With Kinematic Comparison Between Wind-Up And Stretch Pitching With Respect To The Upper And Lower Extremities, Megan M. Smidebush

Theses and Dissertations--Kinesiology and Health Promotion

Introduction: Baseball pitching is considered one of the most intense aspects within the game of baseball, as well as the most complicated dynamic throwing task in all of sports. The biomechanics of pitching have been heavily investigated in an attempt to identify optimal pitching mechanics in terms of pitching performance. Previous quantified upper body kinetics research has concluded that improved muscle strength is needed in attempting to achieve adequate upper body kinetics and efficient pitching performances. Therefore, it is the purpose of this research study to compare the lower extremity muscle and upper extremity muscle activation patterns and kinematic variables …

The Effect Of Sleep Quantity And Quality On Direct Current Potential In Collegiate American Football Players, Erik D. Korem

Theses and Dissertations--Kinesiology and Health Promotion

Direct current (DC) potential is an objective measure of the functional state of the human organism. It is a sensitive and accurate indicator of short- and long-term adaptations to stress, adaptive capacities, and it is an important marker of athlete readiness. Sleep is posited to be the most efficacious strategy for improving recovery to enhance sport performance, and adequate sleep is considered vital to normal psycho-physiological function. Thus, optimal sleep may enhance the functional state, in turn enhancing an athlete’s adaptability to training stress. However, little is known about the relationship between sleep and DC potential. Therefore, the purpose of …

Muscle Synergy During A Single Leg Standing Test In Ambulatory Children With Cerebral Palsy, Brennan L. Smith

Theses and Dissertations--Kinesiology and Health Promotion

INTRODUCTION: Cerebral Palsy (CP) is a sensorimotor disorder characterized by dysfunctional motor coordination, balance problems, and loss of selective motor control. Motor coordination exhibited as co-contraction, has been subjectively quantified using gait analysis, but recent studies have begun to objectively analyze the amount of co-contraction by collecting electromyography (EMG) data. Center of pressure excursion (COPE) measurements collected during a single leg standing test (SLST) have shown to be more valid measurements of balance in populations with motor disabilities than a SLST alone. A recent study has correlated increased COPE velocity with a lower fall risk as determined by reported fall …

Effects Of High Fat Exposure On Skeletal Muscle Autophagy And Endoplasmic Reticulum Stress, Adrienne Rose Herrenbruck

Theses and Dissertations--Kinesiology and Health Promotion

Autophagy is a major degradation mechanism, responsible for clearing damaged and dysfunctional organelles, including the endoplasmic reticulum, a structure essential for protein synthesis and myocellular hypertrophy. Alterations in autophagy throughout various tissues of the body have been linked to various negative side effects such as decreased myocellular hypertrophy and insulin resistance. High fat diets lead to changes (both increases and decreases) in autophagy in various tissues throughout the body in a tissue-specific manner.

Skeletal muscle autophagy is decreased in myotubes cultured from obese women, however the mechanism by which this occurs is unknown. As the largest organ system in the …

Role Of Skeletal Muscle Mass In Sex-Dependent Power Output During Flywheel Resistance Training, Paul A. Baker

Theses and Dissertations--Kinesiology and Health Promotion

Background: To determine the role of muscle mass in sex-dependent differences in power output during flywheel resistance training (FRT).

Methods: Twenty recreationally active (≥ 2 resistance exercise bouts per week), subjects (10 M, 10 F) completed 2 bouts of resistance exercise using a flywheel resistance training (FRT) device (Exxentric kbox 4 Pro) separated by at least one week. Each session consisted of 3 sets of 4 exercises (squat, bent-over row, Romanian deadlift, and biceps curl) with varying moments of inertia (0.050, 0.075, and 0.100 kg/m², respectively) in random order. Each set consisted of 5 maximal effort repetitions with …

The Biomechanical Impact Of Weight On The Lower Extremity, Amanda Lee Ransom

Theses and Dissertations--Kinesiology and Health Promotion

Background: Obesity is a chronic disease characterized by a body mass index (BM1) of ≥ 30 kg/m² which negatively impacts the musculoskeletal system and has been found to be a major contributing factor to obesity-induced biomechanical alterations during activities of daily living (ADLs). A certain level of mobility is required for all populations to maintain independence and a good quality of life becomes more difficult with excess weight. Using a reduced weight-bearing activity, such as the Alter Gravity treadmill, would be beneficial in an obese population to reduce the load on the joints and potentially decrease the risk of …

Effects Of Inertial Load On Sagittal Plane Kinematics During Flywheel-Based Resistance Training Squats, Katherine Sara Worcester

Theses and Dissertations--Kinesiology and Health Promotion

Background: Training to increase muscular power is essential for improving athletic performance in most sports. Weight training (WT) is a common means for training muscular power. Another modality, flywheel resistance training (FRT), may be superior for improving muscular power. However, few studies have examined if FRT is kinematically similar to WT, or if FRT kinematics change with increasing inertial load. The purposes of this study were to determine how sagittal plane joint kinematics are affected by increasing inertial load during FRT squats, and to determine how FRT squat joint kinematics compare to WT squat joint kinematics.

Methods: Subjects (n=9) completed …

Association Of Dietary Intake With Suicidal Ideation Or Suicide Attempts In Adolescents, Zenobia J. Bryant

Walden Dissertations and Doctoral Studies

Suicide is among the leading cause of adolescent deaths worldwide and thus a significant public health concern. Risk factors for suicidal behavior include drinking alcohol, smoking, and engaging in risky sexual behaviors. One area of concern is dietary patterns and their association with depressive symptoms and suicidal ideation. Bandura's social cognitive theory emphasizes the assumption that one can perform specific actions to bring about desired outcomes. The primary research questions for this quantitative, retrospective, cross-sectional study concerned whether there is a statistically significant interaction between fruit and vegetable intake and suicidal ideation or suicide attempts. Data from 71,776 adolescents in …

Individual Understanding Of The Risks Associated With Polypharmacy, Michelle Patricia Mchenry

Walden Dissertations and Doctoral Studies

With many individuals experiencing multimorbidity, individuals are being prescribed more medications. Although there are benefits to taking medications to manage symptoms and treat disease processes, there are also risks to taking multiple medications. The purpose of this phenomenological study was to explore participants' understanding of the risks associated with practicing polypharmacy. Game theory, credibility theory, and belief bias were the conceptual frameworks used to explain how individuals experienced their care and being prescribed 5 or more medications. Eight participants residing in subsidized housing in a small Midwest city, who were taking 5 or more medications volunteered to take part in …

A Phenomenological Investigation Of Adult Daughters Of Childhood Paternal Abandonment, Mary Spencer

Walden Dissertations and Doctoral Studies

A father's abandonment of his minor daughter can leave an indelible impression on her psyche -- one that can forever affect her intimate romantic relationships. The purpose of this qualitative phenomenological study was to explore where women who were abandoned by their fathers prior to the age of 18 are today as adults in terms of their intimate romantic relationships and how they develop and engage in these relationships. The research questions examined how a daughter being abandoned by her father prior to the age of 18 relates to where she is today in her adult intimate romantic relationships and …

Teaching Heart Failure Patients A Low-Sodium Diet, Karen Faye Wright

Walden Dissertations and Doctoral Studies

Congestive heart failure (CHF) is a progressive medical condition affecting more than 7 million people in the United States (US) with 700,000 new cases reported annually. More than half of those treated for CHF are readmitted at least once a year. The problem addressed by this quality improvement initiative was lack of adherence to low sodium diet (LSD) among CHF patients, knowledge and skill deficit, and excessive 30-day CHF readmissions. The health belief model and the self-care deficit theory guide nurses in acquiring the skills needed to teach LSD. Twelve months of data were selected from 93 CHF readmissions from …

Education Models For Teaching Adults About Modifying Dietary Carbohydrate And Controlling Weight, Vincient Cleamons

Walden Dissertations and Doctoral Studies

The prevalence of diabetes and other pathophysiological conditions has been correlated with the incidence of obesity. A large portion of an adult community in the northwestern United States suffers from excessive weight that has been linked to premature mortality rates and certain forms of diabetes. Excess calories from carbohydrate have been shown to increase weight. Therefore, diets that are modified in carbohydrate and calories may help mitigate weight and obesity comorbidities. This qualitative, single case study's purpose was to explore the methods health care professionals use for teaching adults about controlling weight. Altheide and Johnson's analytic realism theory, in which …

Immunoglobulin Therapy And Primary Immunodeficient Patients' Health-Related Quality Of Life And Well-Being, Niedre Heckman

Walden Dissertations and Doctoral Studies

Individuals born with primary immune deficiency diseases (PIDD) have a dysfunctional immune system, and many are treated by lifelong injections of immunoglobulin therapy. Studies have shown that these patients have low health-related quality of life (HRQOL) and well-being (WB) and that these outcomes might be improved by the availability of therapy innovated according to preferences for fewer needle sticks or a shorter infusion time. Regulators at the U.S. Food and Drug Administration (FDA) have approved therapies innovated per these preferences. However, there is limited data demonstrating how these innovations impact HRQOL and WB. Using the biopsychosocial model, the purpose of …

Effect Of Attentional Capture And Cross-Modal Interference In Multisensory Cognitive Processing, Michael Jennings

Walden Dissertations and Doctoral Studies

Despite considerable research, the effects of common types of noise on verbal and spatial information processing are still relatively unknown. Three experiments, using convenience sampling were conducted to investigate the effect of auditory interference on the cognitive performance of 24 adult men and women during the Stroop test, perception of object recognition and spatial location tasks, and the perception of object size, shape, and spatial location tasks. The data were analyzed using univariate analysis of variance and 1-way multivariate analysis of variance. The Experiment 1 findings indicated reaction time performance for gender and age group was affected by auditory interference …

The Effects Of Daily Ginger Tea Consumption In Reducing Period Discomfort, Kristy Valencia, Sherllie Kartika

Loma Linda University Research Reports

Background

Ginger has been known for its medicinal purposes which includes treating inflammation.⁶ Researchers have observed the effects of ginger capsules to alleviate dysmenorrhea, but few studies have investigated the use of ginger tea.^6,7,9,10,11 The effects of ginger tea on adolescent females have been studied and researchers concluded that ginger reduces menstrual discomfort.^1,2

Objective

The purpose of our study was to observe the effects of daily ginger tea consumption on menstrual discomfort in non-adolescent menstruating women.

Design

Our study was a quantitative, interventional study.

Participants/setting

Subjects were females aged 18 years and above. Participants were mostly students …

Polar Gigantism And Sea Spiders: A Study Of Respiratory Scaling, Steven Joseph Lane

Graduate Student Theses, Dissertations, & Professional Papers

All animals must breathe to survive. The types of primary respiratory structures vary across the metazoa, and the overall size and components of these structures scale with body size. The scaling of respiratory structures has been well studied in vertebrate lungs and gills, but very few, if any studies, have looked at it in terms of cutaneous gas exchange, the process where oxygen moves across the outer integument via diffusion. My dissertation has sought to fill this gap in knowledge by studying animals that use cutaneous respiration, and my work has determined both how the components of their respiratory surfaces …

Lewis’S Woodpecker Nest Success And Habitat Selection In Cottonwood Floodplain Versus Burned Conifer Forests, William M. Blake

Graduate Student Theses, Dissertations, & Professional Papers

Breeding habitat selection influences reproductive outcomes. Habitat selection may be adaptive and benefit populations, but it can also be maladaptive with negative consequences for populations. Understanding habitat selection and its influence on reproductive success, especially in species of concern, is critical for effective management. Lewis’s Woodpecker (Melanerpes lewis) is a Species of Concern that has experienced national population declines. We studied its abundance and reproductive success in two commonly selected breeding forest types (i.e., cottonwood floodplain and mixed-conifer burned), and nest-site characteristics (nest availability, food availability, and vegetation attributes) that have the potential to yield strong differences in …