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Impact Of Lambdacyhalothrin On Arthropod Natural Enemy Populations In Irrigated Rice Fields In Southern Brazil, Leila Lucia Fritz, Elvis Arden Heinrichs, Vilmar Machado, Tiago Finger Andreis, Marciele Pandolfo, Silvia Martins De Salles, Jaime Vargas De Oliveira, Lidia Mariana Fiuza Jan 2013

Impact Of Lambdacyhalothrin On Arthropod Natural Enemy Populations In Irrigated Rice Fields In Southern Brazil, Leila Lucia Fritz, Elvis Arden Heinrichs, Vilmar Machado, Tiago Finger Andreis, Marciele Pandolfo, Silvia Martins De Salles, Jaime Vargas De Oliveira, Lidia Mariana Fiuza

Department of Entomology: Faculty Publications

The present study aimed to determine the selectivity of the pyrethroid lambdacyhalothrin on arthropod natural enemy populations in irrigated rice fields in Rio Grande do Sul, Brazil. The study was conducted at three sites: districts of Cachoeira do Sul, Eldorado do Sul and Capivari do Sul during the crop years of 2007/2008 and 2008/ 2009. Each site consisted of two subareas divided into four plots. One of the subareas received a spray application of 150 ml/ha of lambdacyhalothrin CS 50, while the other subarea was untreated. Arthropods were collected at 2, 15, 30 and 45 days after the application of …

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Does Risk-Neutral Skewness Predict The Cross Section Of Equity Option Portfolio Returns?, Turan G. Bali, Scott Murray Jan 2013

Does Risk-Neutral Skewness Predict The Cross Section Of Equity Option Portfolio Returns?, Turan G. Bali, Scott Murray

Department of Finance: Faculty Publications

We investigate the pricing of risk-neutral skewness in the stock options market by creating skewness assets comprised of two option positions (one long and one short) and a position in the underlying stock. The assets are created such that exposure to changes in the underlying stock price (delta) and exposure to changes in implied volatility (vega) are removed, isolating the effect of skewness. We find a strong negative relation between risk-neutral skewness and the skewness asset returns, consistent with a positive skewness preference. The returns are not explained by well-known market, size, book-to-market, momentum, short-term reversal, volatility, or option market …

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Holocene Variability In Hydrology, Vegetation, Fire, And Eolian Activity In The Nebraska Sand Hills, Usa, Jens Schmieder, Sherilyn C. Fritz, Eric C. Grimm, Kimberly C. Jacobs, Kendrick J. Brown, James Swinehart, Stephen C. Porter Jan 2013

Holocene Variability In Hydrology, Vegetation, Fire, And Eolian Activity In The Nebraska Sand Hills, Usa, Jens Schmieder, Sherilyn C. Fritz, Eric C. Grimm, Kimberly C. Jacobs, Kendrick J. Brown, James Swinehart, Stephen C. Porter

Department of Earth and Atmospheric Sciences: Faculty Publications

This study combined multiple aquatic and terrestrial proxies, including diatoms, pollen, grain size, and bulk-sediment chemistry to reconstruct the history of three lake sites located in the central Sand Hills of Nebraska, USA. Long-term changes in effective moisture are evident at all sites, with significant changes occurring at ~6000, ~4000, and ~ 2000 cal. yr BP. Both aquatic and terrestrial indicators suggest that effective moisture was low between 10,000 and ~6000 cal. yr BP, and that this time interval was the driest period of the Holocene. The dominance of benthic and tychoplanktic diatom taxa indicates relatively shallow lake-level, high sand …

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The Relative Influences Of Climate And Catchment Processes On Holocene Lake Development In Glaciated Regions, Sherilyn C. Fritz, N. J. Anderson Jan 2013

The Relative Influences Of Climate And Catchment Processes On Holocene Lake Development In Glaciated Regions, Sherilyn C. Fritz, N. J. Anderson

Department of Earth and Atmospheric Sciences: Faculty Publications

Following deglaciation, the long-term pattern of change in diatom communities and the inferred history of the aquatic environment are affected by a hierarchy of environmental controls. These include direct climate impacts on a lake’s thermal and hydrologic budgets, aswell as the indirect affects of climate on catchment processes, such as weathering, soil development, microbial activity, fire, and vegetation composition and productivity,which affect the transfer of solutes and particulates from the terrestrial ecosystem into the lake. Some of these catchment influences on lacustrine systems operate as time-dependent patterns of primary succession that are set in motion by glacier retreat. This paper …

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A Gridded Reconstruction Of Warm Season Precipitation For Asia Spanning The Past Half Millennium, Song Feng, Q. Steven Hu, Qianru Wu, Michael E. Mann Jan 2013

A Gridded Reconstruction Of Warm Season Precipitation For Asia Spanning The Past Half Millennium, Song Feng, Q. Steven Hu, Qianru Wu, Michael E. Mann

Department of Earth and Atmospheric Sciences: Faculty Publications

The authors reconstructed May–September precipitation over the Asian continent (5°–55°N, 60°–135°E) back to AD 1470 on the basis of tree-ring data, historical documentary records, ice core records, and the few long-term instrumental data series available in the region. They employed the method of Regularized Expectation Maximization (RegEM) and applied it to 44 subregions within the continent. Verification exercises demonstrate that the reconstruction is skillful over most of the study domain, with eastern China, India, and other regions of humid climate displaying the greatest skill. Lower reconstruction skill is observed in semiarid and arid regions, which was attributable at least in …

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Optimal Estimation For Global Ground-Level Fine Particulate Matter Concentrations, Aaron Van Donkelaar, Randall V. Martin, Robert J. D. Spurr, Eason Drury, Lorraine A. Remer, Robert C. Levy, Jun Wang Jan 2013

Optimal Estimation For Global Ground-Level Fine Particulate Matter Concentrations, Aaron Van Donkelaar, Randall V. Martin, Robert J. D. Spurr, Eason Drury, Lorraine A. Remer, Robert C. Levy, Jun Wang

Department of Earth and Atmospheric Sciences: Faculty Publications

We develop an optimal estimation (OE) algorithm based on top-of-atmosphere reflectances observed by the MODIS satellite instrument to retrieve near-surface fine particulatematter (PM2.5). The GEOS-Chem chemical transport model is used to provide prior information for the Aerosol Optical Depth (AOD) retrieval and to relate total column AOD to PM2.5. We adjust the shape of the GEOS-Chem relative vertical extinction profiles by comparison with lidar retrievals from the CALIOP satellite instrument. Surface reflectance relationships used in the OE algorithm are indexed by land type. Error quantities needed for this OE algorithm are inferred by comparison with AOD …

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Constraints On Aerosol Sources Using Geos-Chem Adjoint And Modis Radiances, And Evaluation With Multisensor (Omi, Misr) Data, Xiaoguang Xu, Jun Wang, Daven Henze, Wenjun Qu, Monika Kopacz Jan 2013

Constraints On Aerosol Sources Using Geos-Chem Adjoint And Modis Radiances, And Evaluation With Multisensor (Omi, Misr) Data, Xiaoguang Xu, Jun Wang, Daven Henze, Wenjun Qu, Monika Kopacz

Department of Earth and Atmospheric Sciences: Faculty Publications

We present a new top-down approach that spatially constrains the amount of aerosol emissions using satellite (Moderate Resolution Imaging Spectroradiometer (MODIS)) observed radiances with the adjoint of a chemistry transport model (GEOS-Chem). This paper aims to demonstrate the approach through applying it to a case study that yields the following emission estimates over China for April 2008: 1.73 Tg for SO2, 0.72 Tg for NH3, 1.38 Tg for NOx, 0.10 Tg for black carbon, and 0.18 Tg for organic carbon from anthropogenic sources, which reflects, respectively, a reduction of 33.5%, 34.5%, 18.8%, 9.1%, and 15% in comparison to the prior …

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Dietary Supplementation With Pollen Enhances Survival And Collembola Boosts Fitness Of A Web-Building Spider, Jason M. Schmidt, Julie A. Peterson, Jonathan Lundgren, James D. Harwood Jan 2013

Dietary Supplementation With Pollen Enhances Survival And Collembola Boosts Fitness Of A Web-Building Spider, Jason M. Schmidt, Julie A. Peterson, Jonathan Lundgren, James D. Harwood

Department of Entomology: Faculty Publications

Uncertainties exist about the value of non-prey food for predators that are commonly food-limited, and the dietary conditions where non-prey foods are beneficial for carnivorous species. Prior studies show that large quantities of pollen grains are intercepted in the webs of web-building spiders. We examined the nutritional benefits of pollen as a non-prey food for a common ground-dwelling, sheet web-building spider, Mermessus fradeorum (Berland) (Araneae: Linyphiidae). These predators were provided diets of prey or no prey in the presence and absence of pollen. Treatment effects were quantified by measuring predator body nutrient composition, survival, body size, and offspring production. Per …

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Bacillus Thuringiensis: Transgenic Crops, Julie A. Peterson, John J. Obrycki, James D. Harwood Jan 2013

Bacillus Thuringiensis: Transgenic Crops, Julie A. Peterson, John J. Obrycki, James D. Harwood

Department of Entomology: Faculty Publications

Bacillus thuringiensis (Bt) crops, genetically modified to express insecticidal toxins that target key pests of corn, cotton, rice, potato, and other crops, have been rapidly adopted and have become dominant fixtures in agroecosystems throughout the world. Due to the constitutive nature of Bt toxin expression, insecticidal proteins may be found in nearly all plant tissues, presenting multiple sources for Bt toxins to enter the environment, thus creating complex direct and indirect pathways for non-target organisms to be exposed to insecticidal proteins. The environmental impacts of Bt crops have been widely debated, although both benefits and risks do exist. Benefits of …

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The 72-H Webt Microvariability Observation Of Blazar S5 0716+714 In 2009, G Bhatta, Stéphane Vennes Jan 2013

The 72-H Webt Microvariability Observation Of Blazar S5 0716+714 In 2009, G Bhatta, Stéphane Vennes

Aerospace, Physics, and Space Science Faculty Publications

Context. The international Whole Earth Blazar Telescope (WEBT) consortium planned and carried out three days of intensive micro-variability observations of S5 0716+714 from February 22, 2009 to February 25, 2009. This object was chosen due to its bright apparent magnitude range, its high declination, and its very large duty cycle for micro-variations. Aims. We report here on the long continuous optical micro-variability light curve of 0716+714 obtained during the multi-site observing campaign during which the Blazar showed almost constant variability over a 0.5 mag range. The resulting light curve is presented here for the first time. Observations from participating observatories …

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Modeling The X-Ray Light Curves Of Cygnus X-3 Possible Role Of The Jet, Osmi Vilhu, Diana Carina Hannikainen Jan 2013

Modeling The X-Ray Light Curves Of Cygnus X-3 Possible Role Of The Jet, Osmi Vilhu, Diana Carina Hannikainen

Aerospace, Physics, and Space Science Faculty Publications

Context. We address the physics behind the soft X-ray light curve asymmetries in Cygnus X-3, a well-known microquasar. Aims. Observable eff ects of the jet close to the line-of-sight were investigated and interpreted within the frame of light curve physics. Methods. The path of a hypothetical imprint of the jet, advected by theWolf-Rayet-wind, was computed and its crossing with the line-of-sight during the binary orbit determined. We explored the possibility that physically this “imprint” is a formation of dense clumps triggered by jet bow shocks in the wind (“clumpy trail”). Models for X-ray continuum and emission line light curves were …

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Consumer Attitudes And Labeling Regime Key To The Market Potential Of Food Nanotechnology, Miah Tran, Amalia Yiannaka, Konstantinos Giannakas Jan 2013

Consumer Attitudes And Labeling Regime Key To The Market Potential Of Food Nanotechnology, Miah Tran, Amalia Yiannaka, Konstantinos Giannakas

CAFIO: Policy Research Group Policy Pagers

Research shows that, even though most consumers lack knowledge and understanding of the technology, they nevertheless have strong opinions as to its potential risks and benefits. Advocates are determined to not repeat the mistakes of biotechnology. Understanding the factors determining the market acceptance of food nanotechnology and its potential impact on the different interest groups involved can inform the design of effective policies and strategies governing food nanotechnology innovations.

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Country-Of-Origin-Labeling Creates Winners And Losers Among Consumers, Producers, And Retailers, Konstantinos Giannakas, Alejandro Plastina, Daniel Pick Jan 2013

Country-Of-Origin-Labeling Creates Winners And Losers Among Consumers, Producers, And Retailers, Konstantinos Giannakas, Alejandro Plastina, Daniel Pick

CAFIO: Policy Research Group Policy Pagers

Public Law 107-171, the United States Farm Security and Rural Investment Act of 2002, required country-of-origin labeling (COOL) for beef, lamb, pork, fish, perishable agricultural commodities, and peanuts. While the aim is to benefit domestic consumers by allowing them to make informed decisions, the effects of COOL have been the subject of a heated on-going debate. Advocates of COOL argue the existence of an “overwhelming” consumer support for country of origin information and benefits that substantially outweigh the costs of this labeling regime. Opposing groups have expressed concerns about the potential competitive disadvantage that non-integrated producers might face due to …

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Consumer-Oriented Gm Products Can Hurt Producers, Konstantinos Giannakas, Rim Lassoued Jan 2013

Consumer-Oriented Gm Products Can Hurt Producers, Konstantinos Giannakas, Rim Lassoued

CAFIO: Policy Research Group Policy Pagers

Despite their important agronomic benefits to agricultural producers, GM products (GMPs) have been facing a, rather strong, consumer opposition. This opposition varies significantly between countries and so does the countries’ regulatory response to products of biotechnology. While the US treats biotech products as substantially equivalent to their conventional counterparts and does not require their segregation and labeling, the European Union (EU), based on its “precautionary principle” and consumers’ “right to know,” has instituted a mandatory labeling regime that is regarded as the strictest in the world.

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Cafio-Prg Develops Novel Approach To Policy Research, Konstantinos Giannakas Jan 2013

Cafio-Prg Develops Novel Approach To Policy Research, Konstantinos Giannakas

CAFIO: Policy Research Group Policy Pagers

The University of Nebraska-Lincoln has received a grant from the United States Department of Agriculture under the Policy Research Centers Program. This grant has supported the establishment of a Policy Research Group (PRG) as part of the Center for Agricultural and Food Industrial Organization (CAFIO) in the Department of Agricultural Economics. CAFIO-PRG is led by the Project Director, Professor Konstantinos Giannakas, and its main focus is on the development of a novel, empirically relevant, integrated, multi-market framework of policy analysis.

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Food Labeling Standards Have Significant Welfare And Distributional Impacts, Konstantinos Giannakas, Nicholas Kalaitzandonakes, Alexandre Magnier Jan 2013

Food Labeling Standards Have Significant Welfare And Distributional Impacts, Konstantinos Giannakas, Nicholas Kalaitzandonakes, Alexandre Magnier

CAFIO: Policy Research Group Policy Pagers

Discussions on the appropriate regulatory norms for genetically modified (GM) foods date back to the early 1980s. Thirty years later, a consensus on what such norms should be remains elusive. Some countries, including the United States and Canada, consider GM foods substantially equivalent to their conventional counterparts and do not require segregation and labeling of these products. Others, including the European Union, Japan, South Korea, New Zealand, Australia, and China have introduced mandatory labeling regimes.

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Empathy Nudging Increases Conservation Of Farming Land, Natalia V. Czap, Hans J. Czap, Gary D. Lynne, Mark E. Burbach Jan 2013

Empathy Nudging Increases Conservation Of Farming Land, Natalia V. Czap, Hans J. Czap, Gary D. Lynne, Mark E. Burbach

CAFIO: Policy Research Group Policy Pagers

One of the major challenges of environmental policy with regard to conservation is that it must often rely on voluntary and non-selfish actions of individuals. Traditionally policy makers rely on direct regulation and financial incentives, but both approaches face problems. Regulations may lead to resentment and the costs of perfect enforcement are prohibitively high. Financial incentives can be perverse and may lead to unintended consequences, including crowding out of intrinsic motivation. In addition, behavioral economics and economic psychology studies demonstrate that the assumptions of the neoclassical economic models (such as self-interest only, rationality, and willpower) on which the policy design …

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2013 Farm Bill: An Experimental Test Of The Senate And House Proposals, Natalia V. Czap, Hans J. Czap, Gary Lynne, Mark E. Burbach Jan 2013

2013 Farm Bill: An Experimental Test Of The Senate And House Proposals, Natalia V. Czap, Hans J. Czap, Gary Lynne, Mark E. Burbach

CAFIO: Policy Research Group Policy Pagers

The 2008 Farm Bill currently guides agricultural and related environmental/conservation policy. Versions proposed by the United States Senate and the House of Representatives, to be implemented in the 2013 Farm Bill after differences are resolved, aim to achieve environmental (and other food related) goals, while also seeking significant spending cuts. While both versions propose to eliminate the Direct Payments program, they differ with respect to how other crop supports should work and whether crop insurance subsidies should be linked to conservation practices. The Senate Bill supports a policy design based on cross‐compliance, that is, crop insurance subsidies are conditional on …

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Azimuthal Anisotropy Of Π⁰ And Η Mesons In Au + Au Collisions At √Snn=200, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Marcus Hohlmann Jan 2013

Azimuthal Anisotropy Of Π⁰ And Η Mesons In Au + Au Collisions At √Snn=200, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Marcus Hohlmann

Aerospace, Physics, and Space Science Faculty Publications

The azimuthal anisotropy coefficients v₂ and v₄ of π⁰ and η mesons are measured in Au + Au collisions at √sNN=200 GeV as a function of transverse momentum pT (1-14 GeV/c) and centrality. The extracted v₂ coefficients are found to be consistent between the two meson species over the measured pT range. The ratio of v₄/v₂² for π⁰ mesons is found to be independent of pT for 1-9 GeV/c, implying a lack of sensitivity of the ratio to the change of underlying physics with pT. Furthermore, the ratio of v₄/v₂² is systematically larger in central collisions, which may reflect the …

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Properties Of The Thundercloud Discharges Responsible For Terrestrial Gamma-Ray Flashes, Joseph R. Dwyer, Ningyu Liu, Hamid K. Rassoul Jan 2013

Properties Of The Thundercloud Discharges Responsible For Terrestrial Gamma-Ray Flashes, Joseph R. Dwyer, Ningyu Liu, Hamid K. Rassoul

Aerospace, Physics, and Space Science Faculty Publications

The source of terrestrial gamma-ray flashes (TGFs) has been an active area of research since their discovery by Compton Gamma-Ray Observatory/Burst and Transient Source Experiment in 1994. These intense bursts of gamma rays originate within thunderclouds via the rapid production of relativistic runaway electrons, accelerated by thundercloud/lightning electric fields to multi-MeV energies. Recent studies have shown that electrical discharges within thunderclouds caused by these runaway electrons can generate currents that rival those of lightning and so could serve as an alternative discharge path for thunderclouds. In particular, the discharges responsible for TGFs produce some of the largest amplitude VLF-LF radio …

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Formation Of Sprite Streamers At Subbreakdown Conditions From Ionospheric Inhomogeneities Resembling Observed Sprite Halo Structures, Burcu C. Kosar, Ningyu Liu, Hamid K. Rassoul Jan 2013

Formation Of Sprite Streamers At Subbreakdown Conditions From Ionospheric Inhomogeneities Resembling Observed Sprite Halo Structures, Burcu C. Kosar, Ningyu Liu, Hamid K. Rassoul

Aerospace, Physics, and Space Science Faculty Publications

Modeling results of sprite streamer formation from large ionospheric inhomogeneities or patches (several tens to hundreds of meter wide) indicate that positive streamers can be initiated at subbreakdown conditions from the inhomogeneities with a density comparable to sprite halo densities. For spherical patches with a given radius, the minimum density required for streamer initiation decreases with increasing ambient field. For a given density, the minimum size of the inhomogeneity decreases with increasing ambient field. The modeling results on the associated optical emissions show that a luminous spherical-like cap appears around the lower tip of the ionization patch before streamer initiation, …

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Radio Emissions From Terrestrial Gamma-Ray Flashes, Joseph R. Dwyer, Steven A. Cummer Jan 2013

Radio Emissions From Terrestrial Gamma-Ray Flashes, Joseph R. Dwyer, Steven A. Cummer

Aerospace, Physics, and Space Science Faculty Publications

The theory of radio frequency (RF) emissions by terrestrial gamma-ray flashes (TGFs) is developed. These radio emissions, which are separate from the emission caused by lightning, are produced by the electric currents generated by runaway electrons and resulting low-energy electrons and ions. It is found from theory that the radio frequency pulses produced by TGFs are large enough to measure. Features of these signals depend strongly on certain aspects of the runaway acceleration process and so should provide additional information about the source mechanism(s) of this interesting atmospheric phenomenon. The RF emissions from several TGF models are calculated and compared …

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The Angular Distribution Of Energetic Electron And X-Ray Emissions From Triggered Lightning Leaders, M. M. Schaal, Joseph R. Dwyer, Hamid K. Rassoul, Jonathan David Hill, Douglas M. Jordan, Martin A. Uman Jan 2013

The Angular Distribution Of Energetic Electron And X-Ray Emissions From Triggered Lightning Leaders, M. M. Schaal, Joseph R. Dwyer, Hamid K. Rassoul, Jonathan David Hill, Douglas M. Jordan, Martin A. Uman

Aerospace, Physics, and Space Science Faculty Publications

We investigate individual X-ray bursts from lightning leaders to determine if energetic electrons at the source (and hence X-rays) are emitted isotropically or with some degree of anisotropy. This study was motivated by the work of Saleh et al. (2009), which found the falloff of X-rays in concentric radial annuli, covering all azimuthal directions in each annulus, from the lightning channel to be most consistent with an isotropic electron source. Here we perform a statistical analysis of angular and spatial distributions of X-rays measured by up to 21 NaI/PMT detectors at the International Center for Lightning Research and Testing site …

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Analysis Of The Experiment On Registration Of X-Rays From The Stepped Leader Of A Cloud-To-Ground Lightning Discharge, Leonid P. Babich, Igor M. Kutsyk, Evgeni N. Donsko, Joseph R. Dwyer Jan 2013

Analysis Of The Experiment On Registration Of X-Rays From The Stepped Leader Of A Cloud-To-Ground Lightning Discharge, Leonid P. Babich, Igor M. Kutsyk, Evgeni N. Donsko, Joseph R. Dwyer

Aerospace, Physics, and Space Science Faculty Publications

Using a Monte Carlo technique to simulate the transport of runaway electrons (REs) and X-rays in the atmosphere and through attenuators covering detectors, we have modeled the results of experiments to detect X-rays from triggered lightning and stepped leaders of a natural cloud-to-ground lightning. In the model, bremsstrahlung of high-energy runaway electrons (REs) generated at the leader front is assumed to be the origin of X-rays. Specific fluxes (per one RE) of photons and bremsstrahlung energy at the detectors were calculated. The analysis was executed with monoenergetic and exponential initial energy distributions of REs with different angular distributions. To reproduce …

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Radio Signals From Electron Beams In Terrestrial Gamma Ray Flashes, Valerie Connaughton, Joseph R. Dwyer, Eric Cramer Jan 2013

Radio Signals From Electron Beams In Terrestrial Gamma Ray Flashes, Valerie Connaughton, Joseph R. Dwyer, Eric Cramer

Aerospace, Physics, and Space Science Faculty Publications

We show that the rate of association between terrestrial gamma ray flashes (TGFs) observed by the Fermi gamma ray burst monitor and VLF discharges detected by the World Wide Lightning Location Network (WWLLN) depends strongly on the duration of the TGF, with the shortest TGFs having associated WWLLN events over 50% of the time, and the longest TGFs showing a less than 10% match rate. This correlation is stronger if one excludes the WWLLN discharges that are not simultaneous (within 200 ms) with the TGF. We infer that the simultaneous VLF discharges are from the relativistic electron avalanches that are …

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Modeling Terrestrial Gamma Ray Flashes Produced By Relativistic Feedback Discharges, Ningyu Liu, Joseph R. Dwyer Jan 2013

Modeling Terrestrial Gamma Ray Flashes Produced By Relativistic Feedback Discharges, Ningyu Liu, Joseph R. Dwyer

Aerospace, Physics, and Space Science Faculty Publications

This paper reports a modeling study of terrestrial gamma ray flashes (TGFs) produced by relativistic feedback discharges. Terrestrial gamma ray flashes are intense energetic radiation originating from the Earth’s atmosphere that has been observed by spacecraft. They are produced by bremsstrahlung interactions of energetic electrons, known as runaway electrons, with air atoms. An efficient physical mechanism for producing large fluxes of the runaway electrons to make the TGFs is the relativistic feedback discharge, where seed runaway electrons are generated by positrons and X-rays, products of the discharge itself. Once the relativistic feedback discharge becomes self-sustaining, an exponentially increasing number of …

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Effects Of Different Geomagnetic Storm Drivers On The Ring Current: Crcm Results, W. Douglas Cramer, Niescja E. Turner, M. C. Fok, N. Yu Buzulukova Jan 2013

Effects Of Different Geomagnetic Storm Drivers On The Ring Current: Crcm Results, W. Douglas Cramer, Niescja E. Turner, M. C. Fok, N. Yu Buzulukova

Aerospace, Physics, and Space Science Faculty Publications

The storm-time magnetic disturbance at the Earth’s equator, as commonly measured by the Dst index, is induced by currents in the near-Earth magnetosphere. The ring current is generally considered the most important contributor, but other magnetospheric currents have also been found to have significant effects. Of the two main types of solar geomagnetic storm drivers, Coronal Mass Ejections (CMEs) tend to have a much greater impact on Dst than Corotating Interaction Regions (CIRs). Ring current models have been found to underestimate Dst, particularly during storms driven by CIRs. One possible explanation is that the models neglect to handle some aspect …

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Making Horses Drink: Conceptual Change Theory And Federal Rule Of Evidence 502, Liesa L. Richter Jan 2013

Making Horses Drink: Conceptual Change Theory And Federal Rule Of Evidence 502, Liesa L. Richter

Faculty Articles

No abstract provided.

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Revisiting Omnicare: What Does Its Status 10 Years Later Tell Us?, Megan Wischmeier Shaner Jan 2013

Revisiting Omnicare: What Does Its Status 10 Years Later Tell Us?, Megan Wischmeier Shaner

Faculty Articles

No abstract provided.

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Re-Purposing The Dram Shop Law To Subordinate The Claims Of Reckless Bartenders Of Credit Drunks: In Bankruptcy, This One Should Be On The House, F. Stephen Knippenberg Jan 2013

Re-Purposing The Dram Shop Law To Subordinate The Claims Of Reckless Bartenders Of Credit Drunks: In Bankruptcy, This One Should Be On The House, F. Stephen Knippenberg

Faculty Articles

No abstract provided.

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