Determining the role of tumor-derived leukemia inhibitory factor in cancer cachexia using a genetic approach

Cachexia is a multifactorial metabolic wasting syndrome that affects a large percentage of cancer patients and results in the involuntary loss of skeletal muscle and adipose tissue. The consequences of this condition include metabolic imbalances and fatigue, which are strongly associated with poor prognosis. While the specific mechanism for skeletal muscle wasting is still undefined, LIF secreted by C26 colon carcinoma cells has recently be found to induce atrophy in treated myotubes. The purpose of this study is to determine the necessity of LIF for inducing atrophy in mouse myotubes by producing a knockout of Lif in C26 cells using CRIPSR-Cas9. Media was collected from these cells and used to treat myotubes. Measurements of myotube diameters were made and atrophy was compared between myotubes that received medium from C26 and C26Lif-/- cells. A dosage of recombinant mouse LIF was also added to LIF-deficient medium in order to determine if LIF alone was sufficient to induce atrophy. At study endpoint, myotubes that were treated with media taken from C26 cells showed significant signs of atrophy compared to myotubes that were treated C26Lif-/- media. LIF was also shown to be sufficient to induce myotube atrophy on its own, with atrophy being rescued in myotubes that received a dosage of LIF added to C26Lif-/- media. These results demonstrate that LIF is required for atrophy to be induced in mouse myotubes treated with media taken from cancer cells, and can do so independent of other secreted factors

The Effects Of Secondary Task Demandon The Assessment Of Threat

Threat perception is an important issue in today\u27s world. As the line between hostile and non-hostile entities is blurred, it becomes more important for individuals to clearly distinguish between those who would present danger and those who would not. This series of experiments tested whether observers engaged in a dual-task paradigm perceived a greater amount of threat from target stimuli than they did when they were engaged in the threat task alone. The first experiment revealed that observers rated targets as more threatening when they were engaged in the additional task than when they only rated the targets themselves. Response time to the targets was also slower when a secondary task was present. This difference was more pronounced when the secondary task was presented via the auditory channel. Participants also rated overall workload higher when performing a secondary task, with the highest ratings being associated with the dual-task auditory condition. In the second experiment, the design crossed sensory modality with the presence or non-presence of threat. Inter-stimulus interval was also manipulated. The presence of threat was associated with faster response times, though when both tasks had threat components, response time was not the fastest. Additionally, when images came first in the stimulus pairs, observers were slower to respond to the first stimulus than when the sounds were presented first. Results supported the conclusion that additional task loading can affect the perception of threat. The modality of the additional task seems to also play a role in threat assessment performance. Results also led to the conclusion that threat-related visual stimuli are more challenging to process than threat-related auditory stimuli. Future research can now investigate how different types of tasks affect the threat perception task. Implications for better training of soldiers and for the design of automated systems are presented

Principal points, principal curves and principal surfaces

The idea of approximating a distribution is a prominent problem in statistics. This dissertation explores the theory of principal points and principal curves as approximation methods to a distribution. Principal points of a distribution have been initially introduced by Flury (1990) who tackled the problem of optimal grouping in multivariate data. In essence, principal points are the theoretical counterparts of cluster means obtained by the k-means algorithm. Principal curves defined by Hastie (1984), are smooth one-dimensional curves that pass through the middle of a p-dimensional data set, providing a nonlinear summary of the data. In this dissertation, details on the usefulness of principal points and principal curves are reviewed. The application of principal points and principal curves are then extended beyond its original purpose to well-known computational methods like Support Vector Machines in machine learning

Saigon to Baghdad : comparing combat correspondents' experiences in Vietnam and Iraq

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file (viewed on September 2, 2008)Thesis (M.A.) University of Missouri-Columbia 2008.This study compared the responses of journalists who covered the Vietnam War with responses of reporters who covered the conflict in Iraq to measure differences and similarities. The comparison showed that reporters working in Iraq faced more constraints in accessing the news because of greater physical danger and less cooperation from the military. Vietnam era journalists had fewer dangers and worked with a military more willing to facilitate coverage. The rules covering embedded journalists in Iraq were more limiting than what journalists in Vietnam encountered. Vietnam era journalists were more likely to use confidential sources than those who covered Iraq. Reporters in Iraq had the benefit of improved technology that enabled them to deliver news more quickly and reliably. This also enabled troops in the field to see what reporters were writing about them. Journalists said the technological improvements should make coverage more accurate. Vietnam era reporters were more likely to have had prior military experience, a difference that might have given them more insight into what was happening. Reporters who covered both wars were drawn to the challenge of tackling the "big story" despite the danger. Journalists in both conflicts said they bonded with the troops they covered and formed personal views of the wars. They said they did not believe these relationships or beliefs affected their reporting.Includes bibliographical reference

Resilience and Emotional Depletion as Predictors of Dyadic Satisfaction of Psychologists in Pennsylvania

Although psychologists have been practicing for nearly one hundred years, relatively little research has been conducted on the impact of the profession upon the psychologist\u27s personal life. Historically, most studies have attempted to determine whether the practice of psychology leads to burnout or impairment rather than what helps a psychologist to function well. A growing body of research on self-care places an emphasis on the personhood of the clinician and his or her ability to function well in practice and personal life (Alterman, 1998). The purpose of this study is to add to the growing body of literature that addresses clinician self-care by investigating the relationship between resilience, emotional depletion, sources of stress in clinical practice and dyadic satisfaction. A sample of 190 doctoral level licensed psychologists from Pennsylvania who were also members of the American Psychological Association (APA), were surveyed using the Well-Functioning Questionnaire, Revised Dyadic Adjustment Scale, Maslach Burnout Inventory - Third Edition, Sources of Stress in Clinical Practice, and About You, a demographic survey. No evidence was found to indicate that practicing psychology has an effect upon dyadic satisfaction. However, the data support a positive relationship among Resilience, Personal Accomplishment and Dyadic Satisfaction. Findings suggest that there are eight behaviors and or characteristics that consistently contribute greatly to the well-functioning of psychologists, and three factors, physical rest, emotional restoration and belief in efficacy that are essential to managing stress in clinical practice. Further research on self-care and the well-functioning of psychologists is needed

The organizational environment and its effects on organizational processes

The objectives of this research were to (1) examine the historical and social science literature on the effects of environmental dynamics on social units, (2) examine and resolve the methodological problems associated with empirically assessing the impact of a multidimensional concept on other variables and (3) develop and empirically evaluate a theoretical model of the effects of perceived environmental uncertainty on organizational structures and processes. The research found a clear progression of thought through the classical social philosophers emphasizing the effects of environmental dynamics. The major problem of reliability estimation for multidimensional concepts was resolved through an application of a relatively unknown psychometric technique and its application to Joreskog\u27s confirmatory factor analysis method, Fuller\u27s errors-in-variables regression method and least squares regression is developed. Finally, a theoretical model of perceived environmental uncertainty was developed and tested using bivariate and multivariate structural equation modeling techniques. The findings clearly show the importance of the concept of environmental uncertainty in organizational research

Habitat Selection by Mexican Spotted Owls in Northern Arizona

We compared use of seven habitat types to availability of those types within the home ranges of eight radio-tagged Mexican Spotted Owls (Strix occidentalis lucida). When all habitat types were considered simultaneously, habitat use differed from habitat availability for each owl. Patterns of habitat use varied among individuals and with respect to activity. Owls generally foraged more than or as frequently as expected in virgin mixed-conifer and ponderosa pine (Pinus ponderosa) forests, and less than expected in managed forests. Owls roosted primarily in virgin mixed-conifer forests. We also compared habitat characteristics among foraging, roosting, and randomly available sites. Habitat characteristics differed significantly among plot types. Both roosting and foraging sites had more big logs, higher canopy closure, and greater densities and basal areas of both trees and snags than random sites. Roosting sites had greater canopy closure, more big logs, and greater densities of both trees and snags than foraging sites. Mature forests appear to be important to owls in this region, and different forest types may be used for different activities

Arctic Standards: Recommendations on Oil Spill Prevention, Response, and Safety in the U.S. Arctic Ocean

Oil spilled in Arctic waters would be particularly difficult to remove. Current technology has not been proved to effectively clean up oil when mixed with ice or when trapped under ice. An oil spill would have a profoundly adverse impact on the rich and complex ecosystem found nowhere else in the United States. The Arctic Ocean is home to bowhead, beluga, and gray whales; walruses; polar bears; and other magnificent marine mammals, as well as millions of migratory birds. A healthy ocean is important for these species and integral to the continuation of hunting and fishing traditions practiced by Alaska Native communities for thousands of years.To aid the United States in its efforts to modernize Arctic technology and equipment standards, this report examines the fierce Arctic conditions in which offshore oil and gas operations could take place and then offers a summary of key recommendations for the Interior Department to consider as it develops world-class, Arctic-specific regulatory standards for these activities. Pew's recommendations call for improved technology,equipment, and procedural requirements that match the challenging conditions in the Arctic and for full public participation and transparency throughout the decision-making process. Pew is not opposed to offshore drilling, but a balance must be achieved between responsible energy development and protection of the environment.It is essential that appropriate standards be in place for safety and for oil spill prevention and response in this extreme, remote, and vulnerable ecosystem. This report recommends updating regulations to include Arctic specific requirements and codifying temporary guidance into regulation. The appendixes to this report provide substantially more detail on the report's recommendations, including technical background documentation and additional referenced materials. Please refer to the full set of appendixes for a complete set of recommendations. This report and its appendixes offer guidelines for responsible hydrocarbon development in the U.S. Arctic Ocean