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Theses/Dissertations

2013

Social and Behavioral Sciences

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Articles 91 - 120 of 142

Full-Text Articles in Life Sciences

Distributed Activity Patterns For Objects And Their Features: Decoding Perceptual And Conceptual Object Processing In Information Networks Of The Human Brain, Marc N. Coutanche Jan 2013

Distributed Activity Patterns For Objects And Their Features: Decoding Perceptual And Conceptual Object Processing In Information Networks Of The Human Brain, Marc N. Coutanche

Publicly Accessible Penn Dissertations

How are object features and knowledge-fragments represented and bound together in the human brain? Distributed patterns of activity within brain regions can encode distinctions between perceptual and cognitive phenomena with impressive specificity. The research reported here investigated how the information within regions' multi-voxel patterns is combined in object-concept networks. Chapter 2 investigated how memory-driven activity patterns for an object's specific shape, color, and identity become active at different stages of the visual hierarchy. Brain activity patterns were recorded with functional magnetic resonance imaging (fMRI) as participants searched for specific fruits or vegetables within visual noise. During time-points in which ...


Stress, Monoamines, And Cognitive Flexibility, Kevin Snyder Jan 2013

Stress, Monoamines, And Cognitive Flexibility, Kevin Snyder

Publicly Accessible Penn Dissertations

Stress has been implicated in psychiatric disorders that are characterized by impaired executive function, which is mediated by the prefrontal cortex (PFC). The stress-related neuropeptide, corticotropin-releasing factor (CRF) regulates monoamine systems that project to the PFC, including the locus coeruleus norepinephrine (LC-NE) system and the dorsal raphe-serotonin (DRN-5-HT) system. CRF actions on these systems may underlie cognitive symptoms of stress-related disorders. The age at which stress occurs can determine its impact, and adolescent stress has been linked to adult psychopathology. This dissertation explores the role of CRF in stress-induced modulation of the LC-NE and DRN-5-HT systems and the developmental time ...


The Neural Representation Of Value And Individual Differences In Human Intertemporal Choice, Nicole Cooper Jan 2013

The Neural Representation Of Value And Individual Differences In Human Intertemporal Choice, Nicole Cooper

Publicly Accessible Penn Dissertations

Intertemporal choices, or decisions that involve tradeoffs between rewards and time, are ubiquitous in our daily lives. The tendency to devalue, or discount, future rewards has been linked to maladaptive long-term health and financial outcomes. Despite their broad clinical relevance, individual differences in discounting preferences are poorly understood. In this thesis, we make progress on the understanding of the neural basis of these decisions and factors that affect individual differences. The first two chapters focus on neurobiology. Chapter 2 investigates the decision-related variables that best explain the observed patterns of BOLD activity in ventromedial prefrontal cortex (VMPFC) and ventral striatum ...


Change And Impact Of Microrna Modification With Age In Drosophila Melanogaster, Masashi Abe Jan 2013

Change And Impact Of Microrna Modification With Age In Drosophila Melanogaster, Masashi Abe

Publicly Accessible Penn Dissertations

microRNAs (miRNAs) are 20~24nt small RNAs that are critical for many biological aspects, from development to age-associated processes. Starting from the identification of the first miRNA, lin-4, hundreds of miRNAs have been discovered across species. To reveal the role of miRNAs in aging, studies have profiled changes in miRNA levels with age. However, increasing evidence suggests that miRNAs show heterogeneity in length and sequence in different biological contexts. Despite the observation of such heterogeneity, it is largely unknown how such heterogeneity is generated, and whether it is biologically regulated or important. Here we report the characterization of a novel ...


Learning And Power In International Farmer Exchanges, Stephen August Lauer Jan 2013

Learning And Power In International Farmer Exchanges, Stephen August Lauer

Graduate Theses and Dissertations

The "Bridging the Gap" program provides an opportunity to explore the relationships between learning and power in international agricultural development partnerships. A USAID-funded partnership between Iowa State University and Volunteer Efforts for Development Concerns, this farmer-to-farmer program sent groups of Iowan women farmers to Uganda to teach Ugandan women farmers with the objectives that Ugandans would move from subsistence to commercial farming and that both groups would benefit from the cultural exchange. Data were collected primarily through semi-structured qualitative interviews of 28 Ugandan farmers, 7 Iowan farmers, and several program staff, and were analyzed using a grounded-theory approach. This thesis ...


Green Roof Biodiversity In Design: Influence Of Local And Contextual Attributes On Bird Usage, Henry Narigon Jan 2013

Green Roof Biodiversity In Design: Influence Of Local And Contextual Attributes On Bird Usage, Henry Narigon

Graduate Theses and Dissertations

This purpose of this research is to identify how species of birds use urban green roofs in Iowa with the intent to eventually develop a set of guidelines for optimizing habitat on green roofs. Ten green roofs were observed for bird usage five times each between May to August, 2013 for a total of fifty observations. Birds were identified by species and their behavior was recorded during the duration of the observations. Data shows that birds use green roofs for a number of uses including foraging and gathering nest material. Bird diversity data was then compared with both green roof ...


Validation And Calibration Of Self-Report Methods: The Youth Activity Profile, Pedro Frederico De Saint-Maurice Maduro Jan 2013

Validation And Calibration Of Self-Report Methods: The Youth Activity Profile, Pedro Frederico De Saint-Maurice Maduro

Graduate Theses and Dissertations

The development of more accurate and precise methods of assessing physical activity behavior is an important public health research priority. Objective monitoring devices have advantages but the high cost and burden of data processing make them impractical for large scale applications. Subjective (survey-based) tools are inexpensive and easy to use but these suffer from questionable validity. Objective measures are often used to validate less accurate measures such as subjective instruments but this does not directly improve the accuracy or precision of the self-report instrument. The proposed line of research developed and tested a calibration equation approach that enabled data from ...


Immunosenescence And Exercise-Mediated Modulation Of The Innate Immune Response To Influenza Infection In Mice, Shibani Naik Jan 2013

Immunosenescence And Exercise-Mediated Modulation Of The Innate Immune Response To Influenza Infection In Mice, Shibani Naik

Graduate Theses and Dissertations

Influenza virus is a negative sense, single stranded RNA virus that can cause severe respiratory tract infections in humans (along with other host animals such as horses, swine and poultry). Certain populations such as very young children, aged individuals, pregnant women and immunosuppressed individuals are more susceptible to influenza infections. One reason for the increased susceptibility to infection in the aged is a decreased efficacy of the seasonal influenza vaccine. As this particular section of our population continues to increase worldwide, research to improve vaccine efficacy is expanding along with efforts to identify lifestyle changes and interventions that can improve ...


Smallholder Farmer Assets, Extension And Marketing In Uganda, Qian Sun Jan 2013

Smallholder Farmer Assets, Extension And Marketing In Uganda, Qian Sun

Graduate Theses and Dissertations

The study was initiated to understand how asset building, combined with appropriate extension services, can enable smallholder farmers to address marketing problems. Interviews were conducted in 2009 with 317 farm households in Kamuli district, Eastern Uganda, who were participants in a sustainable rural livelihoods program, led by an indigenous non-governmental organization with support from Ugandan and U.S. universities. Training and support provided opportunities to improve production of crops and livestock, income, nutrition and well-being. Key research questions are: (i) How is the level of smallholders' assets associated with access to extension services? (ii) What influence do assets and extension ...


Mechanization Potential For Expanding Midwestern Fruit And Vegetable Enterprises, Nicholas Jon Pates Jan 2013

Mechanization Potential For Expanding Midwestern Fruit And Vegetable Enterprises, Nicholas Jon Pates

Graduate Theses and Dissertations

Midwestern fruit and vegetable farmers face challenges in expanding their farms. Growing fruit and vegetables remains a labor intensive industry and most of the country's commercial production takes place on large scale farms in the Western United States. Mechanization may aid farmers in scaling up production by offsetting labor costs. This report uses a six-farm case study and a survey to examine the trends of both labor and machine use over different levels of production. Larger farms tended to use more labor and machinery but machinery seems to exhibit a degree of labor savings potential. The context of expansions ...


A Remote Sensing And Gis-Based Wetland Analysis In Canaan Valley, West Virginia, Yisha Shi Jan 2013

A Remote Sensing And Gis-Based Wetland Analysis In Canaan Valley, West Virginia, Yisha Shi

Theses, Dissertations and Capstones

With the increasing influence in climate change and human activity, more and more people have begun to recognize the benefits of wetlands. However, there was a continuous annual net loss in the wetlands area since 1980s. Many programs have been implemented to monitor the status and trend of wetlands recently. In West Virginia, the wetlands area is a small portion of the State’s land, but it plays a key role in the whole ecosystem. This research aimed to detect the land cover and vegetation changes focusing on Canaan Valley area, which represents the greatest wetlands area of West Virginia ...


The Trade Effects, Protectionism, And Political Economy Of Non-Tariff Measures, Yuan Li Jan 2013

The Trade Effects, Protectionism, And Political Economy Of Non-Tariff Measures, Yuan Li

Graduate Theses and Dissertations

Non-tariff measures (NTMs) have become increasingly present in markets whereas border tariffs have been reduced from successive rounds of General Agreement on Tariffs and Trade (GATT) and the World Trade Organization (WTO). This emergence of NTMs, especially standards like NTMs, has been also motivated by concerns about market imperfections to address asymmetric information and external effects. Sorting protectionism from legitimate market intervention has been difficult and attempts have lack formalism. In addition, the empirical evidence on the impact of these NTMs on trade flows has been cluttered with few obvious implications for policy design. The first essay takes a meta-analysis ...


Fringe Benefits, Catherine Brinkley Jan 2013

Fringe Benefits, Catherine Brinkley

Publicly Accessible Penn Dissertations

This study tests the hypothesis that increased rugosity (the ratio between urban perimeter and farmland area) of the rural-urban fringe allows farms to create greater value for their regions through greater access to urban markets. Findings show that increased rugosity is not associated with farmland loss despite correlating with greater population growth. Rugosity is, instead, associated with higher agricultural sales per acre and more farm-to-city networks. Using the urban interface as a variable to understand farm production and stabilization, this paper includes a spatial statistical analysis of county-level metro-area farm products, farmland loss, and demographics in relation to the concentricity ...


Ovarian Hormone-Induced Neural Plasticity In The Hypothalamic Ventromedial Nucleus, Sarah L. Ferri Jan 2013

Ovarian Hormone-Induced Neural Plasticity In The Hypothalamic Ventromedial Nucleus, Sarah L. Ferri

Publicly Accessible Penn Dissertations

Ovarian hormones act throughout the brain and body to influence a range of functions and behaviors. Estrogens and progesterone are neuroprotective and have important health implications. However, our understanding of the mechanisms underlying many of their actions is incomplete. The goal of this thesis is to elucidate details of ovarian hormone-induced neural plasticity, specifically as it relates to female reproductive behavior and dendritic morphology in the hypothalamic ventromedial nucleus (VMH). First, I tested the hypothesis that the mechanisms of female receptivity are conserved across two species with very different mating strategies: prairie voles, which exhibit monogamy, induced estrous, and induced ...


Effects Of Uncertainty On Perceived And Physiological Stress And Psychological Outcomes In Stroke-Survivor Caregivers, Eeeseung Byun Jan 2013

Effects Of Uncertainty On Perceived And Physiological Stress And Psychological Outcomes In Stroke-Survivor Caregivers, Eeeseung Byun

Publicly Accessible Penn Dissertations

Caregiver status is a known risk factor for morbidity and mortality. In the time period immediately after a stroke, high levels of uncertainty about the family member's recovery and the sudden assumption of a new caregiver role may be acutely stressful. Little is known, however, about caregivers' experiences in the very early period of caregiving or how caregiver stress may contribute subsequently to health. The purpose of this study was to examine the effect of uncertainty on caregiver perceived and physiological stress and psychological outcomes (burden, health-related quality of life [HRQOL] and depressive symptoms) within 2 weeks poststroke (baseline ...


Application Of Remote Sensing In Aquatic Ecosystems, Foad Yousef Jan 2013

Application Of Remote Sensing In Aquatic Ecosystems, Foad Yousef

Dissertations, Master's Theses and Master's Reports - Open

I utilized state the art remote sensing and GIS (Geographical Information System) techniques to study large scale biological, physical and ecological processes of coastal, nearshore, and offshore waters of Lake Michigan and Lake Superior. These processes ranged from chlorophyll a and primary production time series analysies in Lake Michigan to coastal stamp sand threats on Buffalo Reef in Lake Superior. I used SeaWiFS (Sea-viewing Wide Field-of-view Sensor) satellite imagery to trace various biological, chemical and optical water properties of Lake Michigan during the past decade and to investigate the collapse of early spring primary production. Using spatial analysis techniques, I ...


Integrated Classroom Physical Activity: Examining Perceived Need Satisfaction And Academic Performance In Children, Miriam Ann Blom Skrade Jan 2013

Integrated Classroom Physical Activity: Examining Perceived Need Satisfaction And Academic Performance In Children, Miriam Ann Blom Skrade

Graduate Theses and Dissertations

Physical activity is related to better academic performance and prevention of childhood obesity. Classroom-based physical activities, based on recent research studies, seem to target both areas successfully. Move for Thought (M4T) is a recently developed kit that integrates physical activities into academic lessons in the classroom. This thesis is the first to examine the kit's impact on children's motivation and math performance. The study aimed to see (a) if eight weeks of M4T integrated with math, compared to traditional lessons (control), would elicit a gain in math performance and (b) if the basic psychological needs in math (autonomy ...


Essays On Agricultural, Financial Economics And Education, Juan Manuel Murguia Baysse Jan 2013

Essays On Agricultural, Financial Economics And Education, Juan Manuel Murguia Baysse

Graduate Theses and Dissertations

This dissertation is devoted to the study of three different topics under the advice of three different mayor professors. The only thing these topics have in common is the interest and curiosity of the author to explain real life events, using applied econometric techniques. Chapter 2 applies financial tools to assess whether stock values reacted across world markets to the announcement of indexes that synthesize the environmental performance of the world's largest publicly-traded companies. The environmental index selected for this purpose is the "Global 100 Ranking" (G100), a ranking of the 100 largest public companies by market capitalization. The ...


Corn Yield Variability On The Des Moines Lobe Of Iowa: Assessment Of Extent And Soil-Related Causes, Matthew Thomas Streeter Jan 2013

Corn Yield Variability On The Des Moines Lobe Of Iowa: Assessment Of Extent And Soil-Related Causes, Matthew Thomas Streeter

Graduate Theses and Dissertations

Precision agriculture techniques are an essential component to modern row crop agriculture in Iowa and can be used to create crop yield variability maps via geographic information systems. The first objective of this thesis was to explore the methodology that could be used to locate significant long-term corn yield variability on the Iowa Des Moines Lobe. A 158-ha site, consisting mainly of Clarion, Nicollet and Webster soil map units and containing multiple years of geo-referenced corn (Zea mays) yield data was selected. A cluster analysis tool was performed to locate spatially consistent corn yield variability (high, low and mean yield ...


Influences Of Ecological Light Pollution On Advertisement Calls Of Spea Multiplicata (Amphibia: Anura: Scaphiopodidae) In Rural And Urban Populations In The Northern Chihuahuan Desert And An Evaluation Of Hybrid S. Bombifrons X S. Multiplicata Calls, Katie Anderson Jan 2013

Influences Of Ecological Light Pollution On Advertisement Calls Of Spea Multiplicata (Amphibia: Anura: Scaphiopodidae) In Rural And Urban Populations In The Northern Chihuahuan Desert And An Evaluation Of Hybrid S. Bombifrons X S. Multiplicata Calls, Katie Anderson

Open Access Theses & Dissertations

Spea is a genus of toad-like, arid adapted frogs distributed throughout much of the western U.S. and northern Mexico. Two species, (S. Bombifrons and S. Multiplicata) are syntopic throughout most of the northern Chihuahuan Desert, a region that is experiencing rapid urbanization. For this study, I examined 936 male advertisement calls from urban and rural populations of S. multiplicata, and a rural population of S. bombifrons in west Texas and south-central New Mexico. Advertisement calls from urban and rural S. multiplicata were compared against light level to assess the potential influence ecological light pollution plays in sexual selection at ...


Guilty By Association: Time-Dependent Memory Consolidation And The Generalization Of Person-Specific Traits To Other Group Members, Luke R. Enge Jan 2013

Guilty By Association: Time-Dependent Memory Consolidation And The Generalization Of Person-Specific Traits To Other Group Members, Luke R. Enge

Open Access Theses & Dissertations

The following study investigated the extent to which time-dependent memory consolidation facilities the generalization of person-specific traits (individuated targets) to other, familiar social group members (familiar targets) Sixty-Nine (N = 69) participants learned to distinguish between two arbitrary groups, one positive and one negative. Participants learned the negative or positive information about a subset of the group members (individuated targets) and no individuating information about the familiar targets. Participants returned either without a time-delay containing sleep (2-6 hours after learning) or a time-delay with sleep (48 hours after learning). Results demonstrated that only after a time-delay containing sleep, negative information was ...


An Intra-Individual Event-Related Potential-Based Concealed Attitude Test, David R. Herring Jan 2013

An Intra-Individual Event-Related Potential-Based Concealed Attitude Test, David R. Herring

Open Access Theses & Dissertations

The evaluative oddball is an implicit measure for detecting (concealed) attitudes. In evaluative oddball studies, low occurrence stimuli such as negative pictures are presented among high occurrence context stimuli such as positive pictures. Late positive potentials (LPPs) of the event-related potential (ERP) are larger to evaluatively incongruent stimuli such as negatives compared to congruent stimuli such as positives with the context (e.g., positives). In prior evaluative oddball paradigms, this evaluative congruity effect of the LPP was reduced when participants concealed compared to truthfully reported attitudes. Because prior evaluative oddballs have been focused on the group level analysis, it has ...


A Revision Of The New World Ants Of The Genus Platythyrea Roger 1863 (Hymenoptera: Formicidae), Mayra Janett Leyva Jan 2013

A Revision Of The New World Ants Of The Genus Platythyrea Roger 1863 (Hymenoptera: Formicidae), Mayra Janett Leyva

Open Access Theses & Dissertations

The genus Platythyrea consists of arboreal ants that are rarely collected. The genus was last partially revised in 1975 by Brown. Since that revision two additional species have been described. The New World genus Platythyrea now includes nine species: P. angusta Forel, P. exigua Kempf, P. lenca De Andrade, P. pilosula (Smith), P. prizo Kugler, P. punctata (Smith), P. sinuata (Roger), P. strenua Wheeler and P. zodion Brown. A new key, illustrations, diagnoses and distributions of the ants are provided.


Assessing Naturalistic Decision Making By Experienced And Inexperienced Interrogators In High Stakes Interviews, Amy Bethany Ross Jan 2013

Assessing Naturalistic Decision Making By Experienced And Inexperienced Interrogators In High Stakes Interviews, Amy Bethany Ross

Open Access Theses & Dissertations

The current thesis aimed to improve the ecological validity of human intelligence interrogation research. Although field practitioners and researchers have worked together to improve the scientific validity and practical execution of interrogation techniques, research has yet to understand how, when and why interrogators implement such techniques. This thesis investigated the active decision making processes of interrogators that occur during high value interrogations. The theory of Naturalistic Decision Making was used to capture the naturalistic characteristics of high value interrogations- ambiguity, time pressure and high stakes. To capture the decision-making processes that are associated with skilled performance, this research conducted in-depth ...


Economic Optimization And Precision Agriculture: A Carbon Footprint Story, Rachael M. Brown Jan 2013

Economic Optimization And Precision Agriculture: A Carbon Footprint Story, Rachael M. Brown

Theses and Dissertations--Agricultural Economics

This thesis examines the economic and environmental impacts that precision agriculture technologies (PATs) can have on the carbon footprint of a grain farm. An analysis is offered using two manuscripts. The first examines the impacts of three PATs and compares the findings to a conventional farming method. It was found that all three PATs investigated showed a potential Pareto improvement over conventional farming. The second manuscript expanded the model used previously to in order to develop a process to construct a carbon efficient frontier (CEF). The model employed examined uniform and variable rate technologies. In addition to the CEF, a ...


Experiments To Measure The Effects Of Timber Harvesting Equipment On Surface Lithic Scatters, Douglas J. Baughman Jan 2013

Experiments To Measure The Effects Of Timber Harvesting Equipment On Surface Lithic Scatters, Douglas J. Baughman

All Master's Theses

The importance of cultural resource preservation cannot be overstated; however local economies are at least as important. Due to conservative archaeological site protection practices in Region 5 of the United States Forest Service, the economy of Northeastern California is being adversely affected. In an attempt to help the Forest Service make more informed management decisions and improve the Northeastern California economy, I undertook experiments on the effects of timber harvesting on lithic scatters on Modoc National Forest. The experiments involved placement of 225 glass tiles (proxy lithics) in each of three plots subject to vehicle traffic and log dragging by ...


Methylmercury Exposure Affects Risk-Taking Behaviors In Zebra Finches: Tradeoffs Between Eating And Being Eaten, Megan Elizabeth Kobiela Jan 2013

Methylmercury Exposure Affects Risk-Taking Behaviors In Zebra Finches: Tradeoffs Between Eating And Being Eaten, Megan Elizabeth Kobiela

Dissertations, Theses, and Masters Projects

No abstract provided.


Plough Deep While Sluggards Sleep; And You Shall Have Corn To Sell And To Keep: An Analysis Of Plow Ownership In Eighteenth Century York County Virginia, Zachary John Waske Jan 2013

Plough Deep While Sluggards Sleep; And You Shall Have Corn To Sell And To Keep: An Analysis Of Plow Ownership In Eighteenth Century York County Virginia, Zachary John Waske

Dissertations, Theses, and Masters Projects

No abstract provided.


The Effect Of Brand And Caloric Information On Flavor Perception And Food Consumption In Restrained And Unrestrained Eaters, Kevin Vincent Cavanagh Jan 2013

The Effect Of Brand And Caloric Information On Flavor Perception And Food Consumption In Restrained And Unrestrained Eaters, Kevin Vincent Cavanagh

Dissertations, Theses, and Masters Projects

No abstract provided.


Prenatal Stress, Depression, And Herpes Viral Titers, Pao-Chu Hsu Jan 2013

Prenatal Stress, Depression, And Herpes Viral Titers, Pao-Chu Hsu

Graduate Theses and Dissertations

Recent studies suggest that some cases of prenatal depression may be associated with reactivation of latent infections of the herpesvirus family. The possible relationships among stress, prenatal depression, and herpes viral reactivation in pregnancy are understudied and the molecular pathways such as the neuroimmune biogenic amine pathway are unidentified. Chronic stress shifts the T helper-1 cell (Th1) cytokine profile to a Th2 profile, which favors virus induced pathogenesis and survival. Pregnancy is also associated with a similar Th2 dominance. In non-pregnant individuals, exposure to psychological or physical stress may be associated with latent herpes viral reactivation and could result in ...