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Perspectives Of Giant Magnetoresistance, Evgeny Y. Tsymbal, David G. Pettifor

Evgeny Tsymbal Publications

Giant magnetoresistance (GMR) is one of the most fascinating discoveries in thin-film magnetism, which combines both tremendous technological potential and deep fundamental physics. Within a decade of GMR being discovered in 1988 commercial devices based on this phenomenon, such as hard-disk read-heads, magnetic field sensors and magnetic memory chips, had become available in the market. These achievements would not have been possible without a detailed understanding of the physics of GMR, which requires a quantum-mechanical insight into the electronic spin-dependent transport in magnetic structures.

Major Herbicides In Ground Water: Results From The National Water-Quality Assessment, Jack . E. Barbash, Gail P. Thelin, Dana W. Kolpin, Robert J. Gilliom

United States Geological Survey: Staff Publications

To improve understanding of the factors affecting pesticide occurrence in ground water, patterns of detection were examined for selected herbicides, based primarily on results from the National Water-Quality Assessment (NAWQA) program. The NAWQA data were derived from 2227 sites (wells and springs) sampled in 20 major hydro- logic basins across the USA from 1993 to 1995. Results are presented for six high-use herbicides—atrazine (2-chloro-4-ethylamino-6-iso-propylamino- s-triazine), cyanazine (2-[4-chloro-6-ethylamino-1,3,5-triazin-2-yl]amino]-2-methylpropionitrile), simazine (2-chloro-4,6-bis- [ethylamino]-s-triazine), alachlor (2-chloro-N-[2,6-diethylphenyl]-N- [methoxymethyl]acetamide), acetochlor (2-chloro-N-[ethoxymethyl]- N-[ 2-ethyl-6-methylphenyl]acetamide), and metolachlor (2-chloro-N- [2-ethyl-6-methylphenyl]-N-[2-methoxy-1-methylethyl]acetamide)— as well as for prometon (2,4-bis[isopropylamino]-6-methoxy-s-triazine), a nonagricultural herbicide detected frequently during the study. Concentrations were <1 μg L^-1 at 98% …

Martineauian Sociology And Our Disciplinary Future, Michael R. Hill

Department of Sociology: Faculty Publications

I argue above, in concert with my colleagues, that we must take Harriet Martineau seriously, and that there are sound reasons for so doing. The history, sophistication, innovativeness, and continuing resonance of her work and ideas are dramatic, engaging, and impressive by all of the yardsticks used to assess the merit and importance of our sociological founders. We are asked, on occasion, "Yes, but what possible difference does Martineau make to sociology today?" Sheer impudence aside, it is a question to answer carefully, with probity, and our answers must be convincing rather than contrived. The gravity of the question comes …

Play Patterns And Gender, Carolyn P. Edwards, Lisa Knoche, Asiye Kumru

Department of Psychology: Faculty Publications

This cross-cultural analysis examines the gendered patterns of play seen in children worldwide. Play is a culturally universal activity through which children explore themselves and their environment, test out and practice different social roles, and learn to interact with other children and adults. Early in life, children identify themselves as a “girl” or a “boy,” and this basic self-categorization lays a foundation for their developing beliefs about with whom, what, how, and where they will play. Children play an active role in their own and their peers’ “gender socialization” (the process by which they come to acquire the knowledge, values, …

The Impact Of Childhood Sexual Abuse On Later Sexual Victimization Among Runaway Youth, Kimberly A. Tyler, Dan R. Hoyt, Les B. Whitbeck, Ana Mari Cauce

Department of Sociology: Faculty Publications

Path analysis was used to investigate the impact of childhood sexual abuse on later sexual victimization among 372 homeless and runaway youth in Seattle. Young people were interviewed directly on the streets and in shelters by outreach workers in youth service agencies. High rates of both childhood sexual abuse and street sexual victimization were reported, with females experiencing much greater rates compared with their male counterparts. Early sexual abuse in the home increased the likelihood of later sexual victimization on the streets indirectly by increasing the amount of time at risk, deviant peer affiliations, participating in deviant subsistence strategies, and …

Polarimetric Processing Of Coherent Random Noise Radar Data For Buried Object Detection, Yi Xu, Ram M. Narayanan, Xiojian Xu, John O. Curtis

Department of Electrical and Computer Engineering: Faculty Publications

Random noise polarimetry is a new radar technique for high-resolution probing of subsurface objects and interfaces. The University of Nebraska has developed a polarimetric random noise radar system based on the heterodyne correlation technique. Simulation studies and performance tests on the system confirm its ability to respond to phase differences in the received signals. In addition to polarimetric processing capability and the simplified system design, random noise radar also possesses other desirable features, such as immunity from radio frequency interference (RFI). The paper discusses the theoretical foundations of random noise polarimetry, and presents examples out of the entire data set …

Effect Of Creatine On Performance, Tom Smith

Graduate Research Papers

Among the nutritional substances that are suspected of having a performance-enhancing potential, creatine monohydrate has become one of the most popular in recent years. More than 2.5 million kg of creatine was estimated to being consumed in the past year. This can make evident that the expectations of the benefit of creatine by people is very high (Terjung, 2000).

The Olympic motto is "Citius, Altius, Fortius." These three Latin words, translated into English as Swifter, Higher, Stronger, symbolize the Olympic spirit and underlie the ultimate goal for Olympic and any athletes in their quest for sport success, which includes the …

A Survey Of Selected Drinking Behaviors Of Student-Koreans At Kook-Min University, Sangmin Kim

Graduate Research Papers

Students, aged 18 to 25, face many responsibilities and challenges such as social development, higher education activities, vocational activities, living arrangements, seeking marital bonds, and developing economic independence. For the college and university student, it is a major stage as a young adult to pursue a higher educational goal and to learn new ways of relating to other students before stepping into a real job environment (Prendergast, 1994). However, along with their responsibilities and personal development, young people might be exposed to negative sides of adulthood. While the majority of college students are responsible for maintaining positive health, it is …

Review Of Feels Like Far: A Rancher's Life On The Great Plains By Linda Hasselstrom, Nancy Zuercher

Great Plains Quarterly (through 2013)

Feels Like Far is a poignant autobiography. Linda Hasselstrom observes like a naturalist, contemplates like a philosopher, and writes like a poet as she pursues her central question: "Death washed away the solid bedrock of my life as I drove back and forth across the plains this year. ... Are these changes in my life vortical growth? Or the destructive confusion of a prairie twister ?" Flashbacks and reflections weave past and present together.

As she ponders her husband's death, her father's aging and death, her mother's decline, her best friend's death, her move from her ranch to Cheyenne, and …

Women's Sense Of Place On The American High Plains, Cary W. Dewit

Great Plains Quarterly (through 2013)

The plight of women on the American Great Plains is a familiar one to anyone who has explored the region's history. Account after account exists of women during the early years of Euro-American settlement who suffered hardship, persevered, and triumphed, or who succumbed to homesickness, lost their children or husbands, and sometimes descended into madness.² The women's historical situation on the Plains has also been popularized in fiction and dramatized or romanticized in dozens of films.³ But what of today's Plains women?

Few sources describe women's contemporary experience of Plains life. Some works have given us a glimpse …

Impact Of Climate And Parent Material On Chemical Weathering In Loess-Derived Soils Of The Mississippi River Valley, Daniel R. Muhs, E. A. Bettis Iii, J. Been, J. P. Mcgeehin

United States Geological Survey: Staff Publications

Peoria Loess-derived soils on uplands east of the Mississippi River the midcontinent of North America (Ruhe, 1969; Hall valley were studied from Louisiana to Iowa, along a south-to-north and Anderson, 2000), Alaska (Muhs et al., 2001), and gradient of decreasing precipitation and temperature. Major element China (Maher et al., 1994). Critical to paleoclimatic interanalyses of deep loess in Mississippi and Illinois show that the composi- pretations, using paleosols, are reliable climofunctions tion of the parent material is similar in the northern and southern for modern soils, which give an understanding of soil parts of the valley. We hypothesized that in …

Polyacrylamide For Surface Irrigation To Increase Nutrient-Use Efficiency And Protectwater Quality, Rodrick D. Lentz, Robert E. Sojka, Charles W. Robbins, Dennis C. Kincaid, Dale T. Westermann

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Furrow irrigation systems have a greater application capacity, are less costly, and use less energy than sprinkler systems but furrow irrigation produces greater runoff, erosion, and deep percolation losses. Phosphorus (P) and nitrogen (N) losses are associated with runoff sediment, and can be minimized by eliminating irrigationinduced erosion. Excessive leaching of inorganic and organic solutes commonly occurs at the inflow region of furrow irrigated fields where infiltration opportunity times are longer. In one conservation practice, a high molecular weight, anionic polyacrylamide (PAM) is applied to advancing furrow stream flows at a concentration of 10 mg L^-1. Because PAM …

Inhibition Of Erythrocyte Δ- Aminolevulinic Acid Dehydratase (Alad) Activity In Fish From Waters Affects By Lead Smelters, Christopher J. Schmitt, Colleen A. Caldwell, Bill Olsen, Dave Serdar

United States Geological Survey: Staff Publications

We assessed the effects on fish of lead (Pb) released to streams by smelters located in Trail, BC (Canada), E. Helena, MT, Herculaneum, MO, and Glover, MO. Fish were collected by electrofishing from sites located downstream of smelters and from reference sites. Blood from each fish was analyzed for δ-aminolevulinic acid dehydratase (ALAD) activity and hemoglobin (Hb), and samples of blood, liver, or carcass were analyzed for Pb, zinc (Zn), or both. Fish collected downstream of all four smelters sites had elevated Pb concentrations, decreased ALAD activity, or both relative to their respective reference sites. At E. Helena, fish from …

Remnant Colloform Pyrite At The Haile Gold Deposit, South Carolina: A Textural Key To Genesis, Nora Foley, Robert A. Ayuso, Robert R. Seal Ii

United States Geological Survey: Staff Publications

Auriferous iron sulfide-bearing deposits of the Carolina slate belt have distinctive mineralogical and textural features—traits that provide a basis to construct models of ore deposition. Our identification of paragenetically early types of pyrite, especially remnant colloform, crustiform, and layered growth textures of pyrite containing electrum and pyrrhotite, establishes unequivocally that gold mineralization was coeval with deposition of host rocks and not solely related to Paleozoic tectonic events. Ore horizons at the Haile deposit, South Carolina, contain many remnants of early pyrite: (1) fine-grained cubic pyrite disseminated along bedding; (2) finegrained spongy, rounded masses of pyrite that may envelop or drape …

2,3,7,8-Tetrachlorodibenzo-P-Dioxin Induces Apoptotic Cell Death And Cytochrome P4501a Expression In Developing Fundulus Heteroclitus Embryos, Barbara Holland Toomey, Susan Bello, Mark E. Hahn, Susannah Cantrell, Peggy Wright, Donald E. Tillitt, Richard T. Di Giulio

United States Geological Survey: Staff Publications

Fundulus heteroclitus embryos were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during early development using nanoinjection or water bath exposure. TCDD caused developmental abnormalities that included hemorrhaging, loss of vascular integrity, edema, stunted development and death. The LC₅₀ and LD₅₀ of TCDD for Fundulus embryos were ~19.7 ± 9.5 pg TCDD/µl (water bath) and 0.25 ± 0.09 ng TCDD/g embryo (nanoinjection). To identify a possible cause for these developmental abnormalities we analyzed the effects of TCDD on apoptotic cell death and cytochrome P4501A (CYP1A) expression in the embryos. TCDD exposure increased apoptotic cell death in several tissues including brain, …

Fluvial Processes And Passive Rehabilitation Of The Lisbon Bottom Side-Channel Chute, Lower Missouri River, Robert B. Jacobson, Mark S. Laustrup, Michael D. Chapman

United States Army Corps of Engineers, Omaha District

Multiple large floods in 1993-1997 on the Lower Missouri River carved a side-channel chute through the river bottom at Lisbon, Missouri. Although similar in some respects to engineered side-channel chutes designed for habitat rehabilitation projects, the Lisbon Bottom chute has been unique in that it was allowed to evolve for more than four years with minimal stabilization. During the wet years, 1996-1999, the chute was subjected to abnormally high discharges and passed as much as 20% of the total discharge of the Missouri River. Relatively unrestrained fluvial processes during this time created a wide channel with highly diverse habitats. The …

Origin Of Late Quaternary Dune Fields On The Southern High Plains Of Texas And New Mexico, Daniel R. Muhs, Vance T. Holliday

United States Geological Survey: Staff Publications

Mostly stabilized late Holocene eolian sands on the Southern High Plains of the United States were studied to determine their origins and to assess whether present dune stability depends more strongly on sediment supply, sediment availability, or transport limitations. Geomorphic, sedimentological, and geochemical trends indicate that late Holocene dunes formed under westerly paleowinds, broadly similar to those of today. Mineralogical and geochemical data indicate that the most likely source for the sands is not the Pecos River valley, but the Pleistocene Blackwater Draw Formation, an older, extensive eolian deposit in the region. These observations suggest that new sand is supplied …

Vegetation And Paleoclimate Of The Last Interglacial Period, Central Alaska, Daniel R. Muhs, Thomas A. Ager, James E. Begét

United States Geological Survey: Staff Publications

The last interglacial period is thought to be the last time global climate was signi"cantly warmer than present. New stratigraphic studies at Eva Creek, near Fairbanks, Alaska indicate a complex last interglacial record wherein periods of loess deposition alternated with periods of soil formation. The Eva Forest Bed appears to have formed about the time of or after deposition of the Old Crow tephra (dated to ~ 160 to ~ 120 ka), and is therefore correlated with the last interglacial period. Pollen, macrofossils, and soils from the Eva Forest Bed indicate that boreal forest was the dominant vegetation and precipitation …

Evolution Of Soils On Quaternary Reef Terraces Of Barbados, West Lndies, Daniel R. Muhs

United States Geological Survey: Staff Publications

Soils on uplifted Quaternary reef terraces of Barbados, ~125,000 to ~700,000 yr old, form a climo-chronosequence and show changes in physical, chemical, and mineralogical properties with terrace age. Parent materials are dust derived from the Sahara, volcanic ash from the Lesser Antilles island arc, and detrital carbonate from the underlying reef limestone. Although some terrace soils are probably eroded, soils or their remnants are redder and more clay-rich with increasing terrace age. Profile-average Al₂O₃ and Fe₂O₃ content increases with terrace age, which partially reflects the increasing clay content, but dithionite-extractable Fe also increases with …

Comparison Of Instream Methods For Measuring Hydrolic Conductivity In Sandy Streambeds, Matthew K. Landon, David L. Rus, F. Edwin Harvey

United States Geological Survey: Staff Publications

Streambed hydraulic conductivity (K) values were determined at seven stream transects in the Platte River Basin in Nebraska using different instream measurement techniques.

The Pacific Island Mapping Program Of The Us Geological Survey, Frank C. Whitmore Jr.

United States Geological Survey: Staff Publications

A little-known aspect of the U.S. Geological Survey history is its involvement in preparing terrain intelligence reports during World War II. The Survey's Military Geology Unit was in charge of compiling these reports on areas of possible military operations. Maps were the main part of' these studies; they were compiled from existing maps, geologic and soils literature, aerial and ground photographs, and travelers' accounts. Compiled geologic anti soils maps served as basic data for interpretative maps on such subjects as construction materials. water supply, road and airfield siting and construction, and cross-country movement by tanks.

Evidence For Millennial-Scale Climate Change During Marine Isotope Stages 2 And 3 At Little Lake, Western Oregon, U.S.A., Laurie D. Grigg, Cathy Whitlock, Walter E. Dean

United States Geological Survey: Staff Publications

Pollen and geochemical data from Little Lake, western Oregon, suggest several patterns of millennial-scale environmental change during marine isotope stage (MIS) 2 (14,100–27,600 cal yr B.P.) and the latter part of MIS 3 (27,600–42,500 cal yr B.P.). During MIS 3, a series of transitions between warm- and cold-adapted taxa indicate that temperatures oscillated by ca. 2±–4±C every 1000–3000 yr. Highs and lows in summer insolation during MIS 3 are generally associated with the warmest and coldest intervals. Warm periods at Little Lake correlate with warm sea-surface temperatures in the Santa Barbara Basin. Changes in the strength of the subtropical high …

Separation Of Notch1 Promoted Lineage Commitment And Expansion/Transformation In Developing T Cells, David M. Allman, Fredrick G. Karnell, Jennifer Punt, Sonia Bakkour

Biology Faculty Scholarship

No abstract provided.

Two Checkpoint Complexes Are Independently Recruited To Sites Of Dna Damage In Vivo, Justine Melo

Biology Faculty Scholarship

The Ddc1/Rad17/Mec3 complex and Rad24 are DNA damage checkpoint components with limited homology to replication factors PCNA and RF-C, respectively, suggesting that these factors promote checkpoint activation by "sensing" DNA damage directly. Mec1 kinase, however, phosphorylates the checkpoint protein Ddc2 in response to damage in the absence of all other known checkpoint proteins, suggesting instead that Mec1 and/or Ddc2 may act as the initial sensors of DNA damage. In this paper, we show that Ddc1 or Ddc2 fused to GFP localizes to a single subnuclear focus following an endonucleolytic break. Other forms of damage result in a greater number of …

Estimated Areal Extent Of Colonies Of Black-Tailed Prairie Dogs In The Northern Great Plains, John Sidle, Douglas Johnson, Betty Euliss

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

During 1997-1998, we undertook an aerial survey, with an aerial line-intercept technique, to estimate the extent of colonies of black-tailed prairie dogs (Cynomys ludovicianus) in the northern Great Plains states of Nebraska, North Dakota, South Dakota, and Wyoming. We stratified the survey based on knowledge of colony locations, computed 2 types of estimates for each stratum, and combined ratio estimates for high-density strata with average density estimates for low-density strata. Estimates of colony areas for black-tailed prairie dogs were derived from the average percentages of lines intercepting prairie dog colonies and ratio estimators. We selected the best estimator …

Occurrence Of Cyanazine Compounds In Groundwater: Degradates More Prevalent Than The Parent Compound, Dana Kolpin, E. Michael Thurman, S. Michael Linhart

United States Geological Survey: Staff Publications

A recently developed analytical method using liquid chromatography/mass spectrometry was used to investigate the occurrence of cyanazine and its degradates cyanazine acid (CAC), cyanazine amide (CAM), deethylcyanazine (DEC), and deethylcyanazine acid (DCAC) in groundwater. This research represents some of the earliest data on the occurrence of cyanazine degradates in groundwater. Although cyanazine was infrequently detected in the 64 wells across Iowa sampled in 1999, cyanazine degradates were commonly found during this study. The most frequently detected cyanazine compound was DCAC (32.8%) followed by CAC (29.7%), CAM (17.2%), DEC (3.1%), and cyanazine (3.1%). The frequency of detection for cyanazine or one …

Effect Of Scale On The Behavior Of Atrazine In Surface Waters, Paul Capel, Steven Larson

United States Geological Survey: Staff Publications

Field runoff is an important transport mechanism by which agricultural pesticides, including atrazine, move into the hydrologic environment. Atrazine is chosen because it is widely used, is transported in runoff relatively easily, is widely observed in surface waters, and has relatively little loss in the stream network. Data on runoff of atrazine from experimental plot and field studies is combined with annual estimates of load in numerous streams and rivers, resulting in a data set with 408 observations that span 14 orders of magnitude in area. The load as a percent of use (LAPU) on an annual basis is the …

Effects Of Landsat 5 Thematic Mapper And Landsat 7 Enhanced Thematic Mapper Plus Radiometric And Geometric Calibrations And Corrections On Landscape Characterization, James E. Vogelmann, Dennis Helder, Ron Morfitt, Michael J. Choate, James W. Merchant, Henry Bulley

United States Geological Survey: Staff Publications

The Thematic Mapper (TM) instruments on board Landsats 4 and 5 provide high-quality imagery appropriate for many different applications, including land cover mapping, landscape ecology, and change detection. Precise calibration was considered to be critical to the success of the Landsat 7 mission and, thus, issues of calibration were given high priority during the development of the Enhanced Thematic Mapper Plus (ETM+). Data sets from the Landsat 5 TM are not routinely corrected for a number of radiometric and geometric artifacts, including memory effect, gain/bias, and interfocal plane misalignment. In the current investigation, the effects of correcting vs. not correcting …

Growth, Structure, Electronic, And Magnetic Properties Of Mgo/Fe(001) Bilayers And Fe/Mgo/Fe(001) Trilayers, M. Klaua, D. Ullmann, J. Barthel, W. Wulfhekel, J. Kirschner, R. Urban, Theodore L. Monchesky, Axel Enders, John F. Cochran, Brett Heinrich

Axel Enders Publications

Single-crystal epitaxial MgO thin films were grown directly onto high-quality Fe single crystal and Fe whisker substrates and covered with Fe/Au layers. Reflection high-energy electron diffraction and low-energy electron diffraction patterns and scanning tunneling microscopy images showed that the growth of MgO proceeded pseudomorphically in a nearly layer-by-layer mode up to six monolayers. A misfit dislocation network is formed for MgO layers thicker than six monolayers. The thin MgO films were characterized electrically by scanning tunneling spectroscopy. The tunneling barrier in MgO was found to depend on the MgO layer thickness, starting from 2.5 eV at two monolayer thickness to …

Design Of A Laboratory Secondary Hazard Study, David A. Goldade, Peter J. Savarie, Jerome C. Hurley, Stanley A. Gaddis, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

Factors influencing the design and execution of a secondary hazard study are presented using the anticoagulant rodenticide, difethialone, as a model. Frequently, regulatory agencies require a determination of the potential hazard posed to non-target species by the application of pesticides. This hazard can occur through: 1) primary hazard, direct consumption of the bait or formulation containing the pesticide, or 2) secondary hazard, indirect consumption of the pesticide via ingestion of biological matrices such as animals or plants containing pesticide residues. In making this determination, the selection of appropriate test species as well as routes and level of exposure are critical. …