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2001

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Major Nutrient Distribution In Relation To The Physical Structure Of The Gulf Of Alaska Shelf, Amy Ruehs Childers Aug 2001

Major Nutrient Distribution In Relation To The Physical Structure Of The Gulf Of Alaska Shelf, Amy Ruehs Childers

Oceanography

The northern Gulf of Alaska is a biologically productive downwelling shelf. Nutrient sources supporting such productivity have not been adequately studied. Thirteen primary stations were occupied twelve times throughout 1998 and 1999 in an attempt to clarify nutrient distributions and sources. The shelf waters were warmer, fresher, lower in nitrate, and higher in phytoplankton biomass in the spring of 1998 compared to 1999. Nitrate, silicate, and phosphate were positively correlated with salinity indicating an offshore nutrient source. The largest rates of new production, estimated from nitrate drawdown in the upper layer between March and July/August, were 2.6 mmole nitrate m⁻² …

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Investigation Of North Pacific Sea Ice Anomalies In The Context Of Atmospheric And Oceanic Variability, Adrienne Tivy Aug 2001

Investigation Of North Pacific Sea Ice Anomalies In The Context Of Atmospheric And Oceanic Variability, Adrienne Tivy

Atmospheric Sciences

This study investigates the main mode of variability in North Pacific sea ice and examines the relationship between sea ice concentration and northern hemispheric climate variability for the period 1968-1997. Through empirical orthogonal function (EOF) analysis, correlations, and composite analysis, it was found that the seesaw pattern (first EOF of wintertime sea ice concentrations) between ice concentrations in the Bering Sea and the Sea of Okhotsk, generally used to characterize North Pacific sea ice, does not adequately address variability in the Sea of Okhotsk. Relationships between the sea ice dipole and the large-scale circulation were investigated and were found to …

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Portrayal Vs. Reality: Images Of African Americans In Magazine Advertisements, Catherine Elizabeth Davis Aug 2001

Portrayal Vs. Reality: Images Of African Americans In Magazine Advertisements, Catherine Elizabeth Davis

Communication

The images of African Americans in magazine advertisements are changing. As these images change, researchers question whether or not African American socioeconomic and familial status are being accurately represented. George Gerbner's cultivation theory suggests that media play a role in shaping people's perceptions of minority groups. Using content analysis, this study compares the portrayal of African American socioeconomic and familial status in magazine advertisements with 1999 United States Census Bureau socioeconomic statistics of African Americans in the United States. This study found that a discrepancy exists between the portrayal and the reality of African American socioeconomic and familial status than …

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Neuroprotection In The Hibernating Brain: Tissue Trauma And Glutamate Studied By Microdialysis, Fang Zhou Aug 2001

Neuroprotection In The Hibernating Brain: Tissue Trauma And Glutamate Studied By Microdialysis, Fang Zhou

Chemistry and Biochemistry

Hibernation, a natural model of tolerance to 'cerebral ischemia', represents a state of pronounced fluctuation in cerebral blood flow where no brain damage occurs. This study systematically investigates the brain tissue response of hibernating and euthermic arctic ground squirrels to CNS trauma, modeled by insertion of microdialysis probes. The effect of glutamate, an excitatory amino acid neurotransmitter, on the cellular response and the origin of the significant amount of gltuamate were determined by quantitative microdialysis study. The present results indicate in euthermic brain tissue a typical inflammatory tissue response evidenced by the presence of activated microglia and astrocytes and the …

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Assessment Of Total Mercury And Methyl Mercury In Selected Subsistence Fish In Western Alaska, Xiaoming Zhang Aug 2001

Assessment Of Total Mercury And Methyl Mercury In Selected Subsistence Fish In Western Alaska, Xiaoming Zhang

Chemistry and Biochemistry

Total Hg (THg) and methylmercury (MeHg) were examined in muscle and liver samples of salmon species (Chinook: Oncorhynchus tshawytscha; Chum: O. keta; Sockeye: O. nerka; Coho: O. kisutch) and freshwater fish species (Pike: Esox lucius; Grayling: Thymallus arcticus; Whitefish: Caregonus nelsoni) collected in 1999 and 2000 from the Western Alaska rivers (Yukon, Kuskokwim, Nushagak and Kvichak). The THg in salmon muscles has a mean value of 62 ng/g (ww). In Pike muscles, THg has a mean value of 879 ng/g. The mean concentrations of THg in Grayling and Whitefish muscle are 153 ng/g and 32 ng/g respectively. In salmon muscle …

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L-Cysteine-Mediated Destabilization Of Dinitrosyl Iron Complexes In Proteins, Paul A. Rogers, Huangen Ding Aug 2001

L-Cysteine-Mediated Destabilization Of Dinitrosyl Iron Complexes In Proteins, Paul A. Rogers, Huangen Ding

Faculty Publications

Nitric oxide is a signaling molecule in intercellular communication as well as a powerful weapon used by macrophages to kill tumor cells and pathogenic bacteria. Here, we show that when Escherichia coli cells are exposed to nitric oxide, its ferredoxin [2Fe-2S] cluster is nitrosylated, forming the dinitrosyl iron complex with a characteristic EPR signal at gav = 2.04. Such formed ferredoxin dinitrosyl iron complex is efficiently repaired in E. coli cells even in the absence of new protein synthesis. However, the repair activity is completely inactivated once E. coli cells are disrupted, indicating that repairing the ferredoxin dinitrosyl iron complex …

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Bioavailability And Chemical Characterization Of Soil Organic Matter In Arctic Soils, Xiaoyan Dai Aug 2001

Bioavailability And Chemical Characterization Of Soil Organic Matter In Arctic Soils, Xiaoyan Dai

Natural Resources

The purpose of this research was to evaluate bioavailability and chemical characteristics of soil organic matter (SOM) in Arctic tundra soils. Five soil horizons in three different sites located in the Arctic Slope of Alaska were used for this research. This thesis comprises five chapters, each of which described a method that can be used to study the bioavailability and chemical characteristics of SOM in these samples. Chapter One used laboratory incubation technique to determine CO2 evolution from the soils. The cumulative CO2 respired from the samples during the incubation period was used as index of bioavailability of SOM. Chapter …

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Radiative Transfer Modeling In The Coupled Atmosphere-Ocean System And Its Application To The Remote Sensing Of Ocean Color Imagery, Banghua Yan Aug 2001

Radiative Transfer Modeling In The Coupled Atmosphere-Ocean System And Its Application To The Remote Sensing Of Ocean Color Imagery, Banghua Yan

Physics

Ocean color is the radiance emanating from the ocean due to scattering by chlorophyll pigments and particles of organic and inorganic origin. Thus, it contains information about chlorophyll concentrations which can be used to estimate primary productivity. Observations of ocean color from space can be used to monitor the variability in marine primary productivity, thereby permitting a quantum leap in our understanding of oceanographic processes from regional to global scales. Satellite remote sensing of ocean color requires accurate removal of the contribution by atmospheric molecules and aerosols to the radiance measured at the top of the atmosphere (TOA). This removal …

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Seasonal Reproductive Endocrinology And Anatomy Of Steller Sea Lions (Eumetopia Jubatus), Heather Louise Harmon Aug 2001

Seasonal Reproductive Endocrinology And Anatomy Of Steller Sea Lions (Eumetopia Jubatus), Heather Louise Harmon

Fisheries

The decline of western Alaskan Steller sea lions (SSLs) may be related to changes in reproductive rates. However, our understanding of SSL reproductive biology is poor. My objectives were to determine if saliva samples are a valid alternative to plasma samples for measurements of peripheral progesterone and testosterone, to describe annual cycles of steroid concentrations, and to provide anatomical verification of reproductive endocrinology. Samples were collected from adult, captive and wild SSLs. Progesterone and testosterone concentrations in paired plasma and saliva samples were highly correlated (96% and 84%, respectively). Captive SSLs had seasonal variations in these steroids that did not …

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An Age Structured Model For Assessment And Management Of Copper River Chinook Salmon, James W. Savereide Aug 2001

An Age Structured Model For Assessment And Management Of Copper River Chinook Salmon, James W. Savereide

Fisheries

Chinook salmon in Alaska support human uses through a variety of fisheries. Age-structured assessment models are rarely used for estimating the abundance of exploited stocks. This thesis develops a model for the Copper River chinook salmon population to show its advantages over typical assessment models. Information consists of catch-age data from three fisheries (commercial, recreational, subsistence), and two sources of auxiliary data (escapement index, spawner-recruit relationship). Four approaches utilizing different information sources are explored. Results suggest that an approach utilizing pooled catch-age data with time-varying brood-year proportions produces the best estimates, although retrospective and sensitivity analyses suggest that all four …

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The Effects Of Windchill Exposure On The Snow Crab, Chionoecetes Opilio, Jonathan J. Warrenchuk Aug 2001

The Effects Of Windchill Exposure On The Snow Crab, Chionoecetes Opilio, Jonathan J. Warrenchuk

Fisheries

Millions of snow crabs, 'Chionoecetes opilio, ' are aerially exposed during sorting in the annual Bering Sea commercial fishery. A laboratory experiment measured snow crab responses to windchill exposure. Crabs were exposed to 8 to 16 m/s windspeed and air temperatures from -2 to -10 C̊ for 5 minutes. Mortality, autonomy, and righting response were assessed for seven days post-treatment. Crabs experienced 40% to 100% mortality at windchill from -10 to 16 C̊. Reduced exposure time significantly reduced mortality. Autonomy was variable but pronounced below -10 C̊ windchill. The righting response was impaired after all but the least severe treatment. …

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Feeding Ecology Of Maturing Sockeye Salmon (Oncorhynchus Nerka) In Nearshore Waters Of The Kodiak Archipelago, Bruce Charles Mcintosh Aug 2001

Feeding Ecology Of Maturing Sockeye Salmon (Oncorhynchus Nerka) In Nearshore Waters Of The Kodiak Archipelago, Bruce Charles Mcintosh

Fisheries

The diet and feeding behavior of maturing sockeye salmon (Oncorhynchus nerka) were investigated during the final marine phase of the spawning migration, prior to reentering natal streams. The stomach contents of commercially caught sockeye salmon, migrating within the nearshore waters of the Kodiak Archipelago during 1998 and 1999, were examined to determine the level of feeding activity and taxa of dominant prey items. Samples were collected throughout the majority of the migration (early June to late August) from areas known to be used principally as migration corridors, and from areas proximate to several natal streams. Dominant prey of sockeye salmon …

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Natural Resource News, Vol. 01, No. 2 (August 2001), N/A N/A Aug 2001

Natural Resource News, Vol. 01, No. 2 (August 2001), N/A N/A

Natural Resource News

No abstract provided.

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Factors Influencing Zooplankton Populations In Alaskan Sockeye Salmon (Oncorhynchus Nerka) Nursery Lakes: Insights From Limnological And Paleolimnological Analyses, Jon N. Sweetman Aug 2001

Factors Influencing Zooplankton Populations In Alaskan Sockeye Salmon (Oncorhynchus Nerka) Nursery Lakes: Insights From Limnological And Paleolimnological Analyses, Jon N. Sweetman

Marine Biology

The relative importance of sockeye salmon, invertebrate predators, and other environmental factors in structuring the size and abundance of zooplankton populations was examined in a series of 23 lakes from southern Alaska. Zooplankton abundance was strongly related to sockeye density, along with nutrient availability and alkalinity. The mean size of Bosmina longirostris, the dominant herbivorous cladoceran, was positively correlated with the abundance of the predatory copepod, Cyclops columbianus. Changes in the size and abundance of Bosmina remains over the past 300-500 years were then determined for sediments from two lakes on Kodiak Island, Alaska. The zooplankton communities showed varying responses …

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A Will To Measure, William S. Murray Aug 2001

A Will To Measure, William S. Murray

The US Army War College Quarterly: Parameters

No abstract provided.

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Professional Education: The Key To Transformation, Henry H. Shelton Aug 2001

Professional Education: The Key To Transformation, Henry H. Shelton

The US Army War College Quarterly: Parameters

No abstract provided.

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Book Reviews, Parameters Editors Aug 2001

Book Reviews, Parameters Editors

The US Army War College Quarterly: Parameters

No abstract provided.

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China's Hunger: The Consequences Of A Rising Demand For Food And Energy, Thomas M. Kane, Lawrence W. Serewicz Aug 2001

China's Hunger: The Consequences Of A Rising Demand For Food And Energy, Thomas M. Kane, Lawrence W. Serewicz

The US Army War College Quarterly: Parameters

No abstract provided.

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Summer Mustang, August 16, 2001 Aug 2001

Summer Mustang, August 16, 2001

Cal Poly Student Newspaper

Student newspaper of California Polytechnic State University, San Luis Obispo, CA.

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Wireless Network, Computers, Student-Run Business To Greet Ud Students When They Return To Campus Aug. 22, University Of Dayton Aug 2001

Wireless Network, Computers, Student-Run Business To Greet Ud Students When They Return To Campus Aug. 22, University Of Dayton

News Releases

News release announces that a wireless computer network will be the latest high-tech initiative to greet University of Dayton students when they arrive for the first day of class.

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Cubesat: The Development And Launch Support Infrastructure For Eighteen Different Satellite Customers On One Launch , Jordi Puig-Suari, Clark Turner, Robert Twiggs Aug 2001

Cubesat: The Development And Launch Support Infrastructure For Eighteen Different Satellite Customers On One Launch , Jordi Puig-Suari, Clark Turner, Robert Twiggs

Small Satellite Conference

Stanford University and California Polytechnic State University have combined efforts to develop a means of launching small picosatellites called CubeSat. The CubeSat is a 10cm cube weighting 1 kg or less. The launching system developed will provide launches for three satellites in one launcher tube. The first mission for this launcher will be to fly six tubes to launch as many as 24 CubeSats in May 2002 on a Kosmotras, Dnepr ELV from Bikinour, Ukraine. Stanford and Cal Poly are providing active technical support for the CubeSat developers, which are mostly universities. Once the CubeSats have been developed by the …

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Design Of A Long-Distance Martian Rover, Elizabeth Butt Aug 2001

Design Of A Long-Distance Martian Rover, Elizabeth Butt

Small Satellite Conference

Martian spacecraft have played a vital part in educating scientists about the Mars environment. Specifically, they have allowed us to believe that there are traces of water present on certain parts of the planet. One major scientific objective goal, based on this discovery, is to further explore these potential water sources. One way to achieve this goal is to send a long-distance Martian rover to Mars so that it can inspect these water sites. Although rovers have had successful missions on Mars, the idea of a long-distance rover involves re-designing many aspects of the past rovers. This paper explores the …

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Eastern Progress - 15 Aug 2001, Eastern Kentucky University Aug 2001

Eastern Progress - 15 Aug 2001, Eastern Kentucky University

Eastern Progress 2001-2002

No abstract provided.

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2001-2002, Collin College Aug 2001

2001-2002, Collin College

Course Catalogs

Contains information on courses and class descriptions as well as campus resources at Collin College.

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Wst2309-001: Women, Men, Culture, Robin Murray Aug 2001

Wst2309-001: Women, Men, Culture, Robin Murray

Fall 2001

No abstract provided.

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Observations Of Scent-Marking And Discriminating Self From Others By A Domestic Dog (Canis Familiaris): Tales Of Displaced Yellow Snow, Marc Bekoff Aug 2001

Observations Of Scent-Marking And Discriminating Self From Others By A Domestic Dog (Canis Familiaris): Tales Of Displaced Yellow Snow, Marc Bekoff

Ethology Collection

Little is known about what stimuli trigger urinating or scent-marking in domestic dogs, Canis familiaris, or their wild relatives. While it is often suggested that the urine of other animals influences urinating and scent-marking patterns in canids, this has not been verified experimentally. To investigate the role of urine in eliciting urinating and marking, in this pilot study I moved urine-saturated snow (‘yellow snow’) from place-to-place during five winters to compare the responses of an adult male domestic dog, Jethro, to his own and others’ urine. Jethro spent less time sniffing his own urine than that of other males or …

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Commentary: Considerations For Use Of Racial/Ethnic Classification In Etiologic Research, Jay S. Kaufman, Richard S. Cooper Aug 2001

Commentary: Considerations For Use Of Racial/Ethnic Classification In Etiologic Research, Jay S. Kaufman, Richard S. Cooper

Faculty Publications

Numerous authors have critiqued the use of race as an etiologic quantity in medical research. Despite this criticism, the use of variables encoding racial/ethnic categorization has increased in epidemiology, and most researchers agree that important variation in disease risk is captured by this classification system. Previous discussions have generally neglected to articulate guidelines for appropriate use of racial/ethnic information in etiologic research. The authors summarize the logical, conceptual, and practical problems associated with the "ethnic paradigm" as currently applied in biomedical sciences and offer a set of methodological recommendations toward more valid use of racial/ethnic classification in etiologic studies. These …

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Kaufman And Copper Respond To "Race,'Racism,And The Practice Of Epidemiology, Jay S. Kaufman, Richard S. Cooper Aug 2001

Kaufman And Copper Respond To "Race,'Racism,And The Practice Of Epidemiology, Jay S. Kaufman, Richard S. Cooper

Faculty Publications

No abstract provided.

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Soundings 2001-08-10 (V.14 No.15), N/A N/A Aug 2001

Soundings 2001-08-10 (V.14 No.15), N/A N/A

Soundings

No abstract provided.

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Use Common Sense, Awareness To Reduce Risk Of Shark Attack, Mitchell Diggs Aug 2001

Use Common Sense, Awareness To Reduce Risk Of Shark Attack, Mitchell Diggs

University of Mississippi News

UNIVERSITY, Miss. -- Visitors to Gulf Coast beaches no doubt are thinking a little more about the possibility of encountering a shark following two widely publicized attacks last month, but the chance of becoming a victim remains pretty slim, a University of Mississippi biologist said.

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