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Quantum Simulation Of High-Order Harmonic Spectra Of The Hydrogen Atom, A. D. Bandrauk, S. Chelkowski, Dennis J. Diestler, J. Manz, K.-J. Yuan

Department of Agronomy and Horticulture: Faculty Publications

Three alternative forms of harmonic spectra, based on the dipole moment, dipole velocity, and dipole acceleration, are compared by a numerical solution of the Schrödinger equation for a hydrogen atom interacting with a linearly polarized laser pulse, whose electric field is given by E(t)= E₀f(t)cos(ω₀t + η) with Gaussian carrier envelope f(t) = exp(−t² /δ²). The carrier frequency ω₀ is fixed to correspond to a wavelength of 800 nm. Spectra for a selection of pulses, for which the intensity I₀=cε₀E²₀, duration T∞ δ, …

Farmers And Nature Conservation: What Is Known About Attitudes, Context Factors And Actions Affecting Conservation?, Johan Ahnström, Jenny Höckert, Hanna L. Bergea, Charles A. Francis, Peter Skelton, Lars Hallgren

Department of Agronomy and Horticulture: Faculty Publications

Farmers’ attitudes towards viability of specific conservation practices or actions strongly impact their decisions on adoption and change. This review of ‘attitude’ information reveals a wide range of perceptions about what conservation means and what the impacts of adoption will mean in economic and environmental terms. Farmers operate in a tight financial situation, and in parts of the world they are highly dependent on government subsidies, and cannot afford to risk losing that support. Use of conservation practices is most effective when these are understood in the context of the individual farm, and decisions are rooted in land and resource …

Evaluation Of The Waxy Endosperm Trait In Proso Millet (Panicum Miliaceum), Robert A. Graybosch, D. D. Baltensperger

Department of Agronomy and Horticulture: Faculty Publications

The entire USDA-ARS maintained collection of 650 accessions of proso millet (Panicum miliaceum L.) was evaluated for the presence of accessions with waxy (amylose-free) endosperm starch. Six accessions, five of which derived from mainland China, were identified. Segregation ratios for waxy endosperm were evaluated in F₂ and F₃ populations derived from crosses between two waxy accessions, PI 436625 (Lung Shu 16) and PI 436626 (Lung Shu 18), and several wildtype accessions. The waxy trait was found to be under the control of duplicate recessive alleles at two loci, herein designated wx-1 and wx-2. Wild-type alleles at …

Light-Induced Fos Expression In Intrinsically Photosensitive Retinal Ganglion Cells In Melanopsin Knockout (Opn4-/-) Mice, Gary E. Pickard, Scott B. Baver, Malcolm D. Ogilvie, Patricia J. Sollars

School of Veterinary and Biomedical Sciences: Faculty Publications

Retinal ganglion cells that express the photopigment melanopsin are intrinsically photosensitive (ipRGCs) and exhibit robust synaptically driven ON-responses to light, yet they will continue to depolarize in response to light when all synaptic input from rod and cone photoreceptors is removed. The light-evoked increase in firing of classical ganglion cells is determined by synaptic input from ON-bipolar cells in the proximal sublamina of the inner plexiform layer. OFF-bipolar cells synapse with ganglion cell dendrites in the distal sublamina of the inner plexiform layer. Of the several types of ipRGC that have been described, M1 ipRGCs send dendrites exclusively into the …

Blood Sampling Reduces Annual Survival In Cliff Swallows (Petrochelidon Pyrrhonota) -- La Toma De Muestras De Sangre Reduce La Supervivencia Anual En Petrochelidon Pyrrhonota, Charles R. Brown, Mary Bomberger Brown

School of Biological Sciences: Faculty Publications

Researchers commonly collect blood samples from wild birds, and most workers assume that blood sampling has no adverse effect on the birds’ survival. Few studies, however, have done controlled comparisons among bled and non-bled individuals and estimated survival using modern statistical methodology. We used a data set on Cliff Swallows (Petrochelidon pyrrhonota) that included 2,945 bled and 7,822 non-bled birds captured at the same times and sites in southwestern Nebraska from 1986 to 2006 to estimate annual survival and recapture probabilities of each group. Blood was collected with brachial venipuncture in amounts varying from 0.3% to 1.2% of …

Long 3’-Utrs Target Wild-Type Mrnas For Nonsense-Mediated Mrna Decay In Saccharomyces Cerevisiae, Bessie W. Kebaara, Audrey L. Atkin

School of Biological Sciences: Faculty Publications

The nonsense-mediated mRNA decay (NMD) pathway,

present in most eukaryotic cells, is a specialized

pathway that leads to the recognition and rapid

degradation of mRNAs with premature termination

codons and, importantly, some wild-type

mRNAs. Earlier studies demonstrated that aberrant

mRNAs with artificially extended 3’-untranslated

regions (3’-UTRs) are degraded by NMD. However,

the extent to which wild-type mRNAs with long

3’-UTRs are degraded by NMD is not known.

We used a global approach to identify wild-type

mRNAs in Saccharomyces cerevisiae that have

longer than expected 3’-UTRs, and of these

mRNAs tested, 91% were degraded by NMD. We

demonstrate for the first …

Interactive Effects Of Time, Co2, N, And Diversity On Total Belowground Carbon Allocation And Ecosystem Carbon Storage In A Grassland Community, E. Carol Adair, Peter B. Reich, Sarah E. Hobbie, Johannes M.H. Knops

School of Biological Sciences: Faculty Publications

Predicting if ecosystems will mitigate or exacerbate rising CO2 requires understanding how elevated CO₂ will interact with coincident changes in diversity and nitrogen (N) availability to affect ecosystem carbon (C) storage. Yet achieving such understanding has been hampered by the difficulty of quantifying belowground C pools and fluxes. Thus, we used mass balance calculations to quantify the effects of diversity, CO₂, and N on both the total amount of C allocated belowground by plants (total belowground C allocation, TBCA) and ecosystem C storage in a periodically burned, 8-year Minnesota grassland biodiversity, CO₂, and N experiment …

Physiological And Taxonomic Description Of The Novel Autotrophic, Metal Oxidizing Bacterium, Pseudogulbenkiania Sp. Strain 2002, Karrie A. Weber, David B. Hedrick, Aaron D. Peacock, J. Cameron Thrash, David C. White, Laurie A. Achenbach, John D. Coates

School of Biological Sciences: Faculty Publications

A lithoautotrophic, Fe(II) oxidizing, nitratereducing bacterium, strain 2002 (ATCC BAA-1479; =DSM 18807), was isolated as part of a study on nitrate-dependent Fe (II) oxidation in freshwater lake sediments. Here we provide an in-depth phenotypic and phylogenetic description of the isolate. Strain 2002 is a gram-negative, non-spore forming, motile, rod-shaped bacterium which tested positive for oxidase, catalase, and urease. Analysis of the complete 16S rRNA gene sequence placed strain 2002 in a clade within the family Neisseriaceae in the order Nessieriales of the Betaproteobacteria 99.3% similar to Pseudogulbenkiania subflava. Similar to P. sublfava, predominant whole cell fatty acids were …

The Impact Of Co-Occurring Tree And Grassland Species On Carbon Sequestration And Potential Biofuel Production, Ramesh Laungani, Johannes Knops

School of Biological Sciences: Faculty Publications

We evaluated how three co-occurring tree and four grassland species influence potentially harvestable biofuel stocks and above- and belowground carbon pools. After 5 years, the tree Pinus strobus had 6.5 times the amount of aboveground harvestable biomass as another tree Quercus ellipsoidalis and 10 times that of the grassland species. P. strobus accrued the largest total plant carbon pool (1375 gCm -2 or 394 gCm -2 yr), while Schizachyrium scoparium accrued the largest total plant carbon pool among the grassland species (421 gCm -2 or 137 gCm -2 yr). Quercus ellipsoidalis accrued 850 gCm -2, Q. macrocarpa 370 gCm -2, …

Occurrence Of Trichosirocalus Horridus (Coleoptera: Curculionidae) On Native Cirsium Altissimum Versus Exotic C. Vulgare In North American Tallgrass Prairie, Masaru Takahashi, Svata M. Louda, Tom E. X. Miller, Charles W. O'Brien

School of Biological Sciences: Faculty Publications

Postrelease studies can provide data with which to evaluate expectations based on prerelease tests of biological control insects. In 2004, we observed Trichosirocalus horridus Panzer (Coleoptera: Curculionidae), the rosette weevil introduced into North America against Eurasian thistles, feeding on native tall thistle, Cirsium altissimum L. Spreng., in tallgrass prairie. In this study, we examined the rosette weevil's use of tall thistle, compared with its use of the co-occurring exotic bull thistle, C. vulgare (Savi) Tenore. For both thistle species, we quantified weevil frequency, abundance, and seasonal variation in incidence, using both timed observations at two sites over two growing seasons …

The Nuclear Receptor Nhr-25 Cooperates With The Wnt/Β-Catenin Asymmetry Pathway To Control Differentiation Of The T Seam Cell In C. Elegans, Martina Hajduskova, Marek Jindra, Michael A. Herman, Masako Asahina

School of Biological Sciences: Faculty Publications

Asymmetric cell divisions produce new cell types during animal development. Studies in Caenorhabditis elegans have identified major signal-transduction pathways that determine the polarity of cell divisions. How these relatively few conserved pathways interact and what modulates them to ensure the diversity of multiple tissue types is an open question. The Wnt/β-catenin asymmetry pathway governs polarity of the epidermal T seam cell in the C. elegans tail. Here, we show that the asymmetry of T-seam-cell division and morphogenesis of the male sensory rays require NHR-25, an evolutionarily conserved nuclear receptor. NHR-25 ensures the neural fate of the T-seam-cell descendants in cooperation …

Effects Of Social Interactions On Empirical Responses To Selection For Average Daily Gain Of Boars, C. Y. Chen, Rodger K. Johnson, S. Newman, Stephen D. Kachman, L. Dale Van Vleck

Department of Animal Science: Faculty Publications

Effects of social interactions on responses to selection for ADG were examined with records of 9,720 boars from dam lines (1 and 2) and sire lines (3 and 4) provided by Pig Improvement Company. Each line was analyzed separately. Pens contained 15 boars. Gains (ADG) were measured from about 71 to 161 d of age and weight from 31 to 120 kg. Models included fixed effects of contemporary groups and initial test age as a covariate, and random direct genetic (d), social genetic (c), social environmental (ce), and litter (lt) effects. Estimates of direct heritability with Model 1 (the full …

Evolution And Pleiotropy Of Trithorax Function In Arabidopsis, Zoya Avramova

School of Biological Sciences: Faculty Publications

The SET domain-containing genes of the TRITHORAX family encode epigenetic factors that maintain the expression of targeted genes. Trithorax homologs have been found in both animals and plants. Since these are thought to have evolved multicellularity independently, common mechanisms of epigenetic regulation must be evolutionarily ancient and derived from a common ancestor. In addition, each lineage has evolved unique mechanisms to expand the original repertoire of epigenetic functions. Phylogenetic analysis of SET domain proteins has outlined some intriguing evolutionary trends. In plants, epigenetic gene silencing mechanisms have been aggressively pursued. In contrast, studies of epigenetic mechanisms maintaining active gene expression …

Ecological Genomics Of Nematode Community Interactions: Model And Non-Model Approaches, Michael A. Herman, Joseph D. Coolon, Kenneth L. Jones, Timothy Todd

School of Biological Sciences: Faculty Publications

The effects of human-induced environmental change are evident at multiple levels of biological organization. To date, most environmental change studies have focused on effects at the ecosystem, community, and organismal levels. However, the ultimate controls of biological responses are located in the genome. Thus, genetic and genomic studies of organismal responses to environmental changes are necessary. Recent advances in genome analysis now make such analyses possible. In this chapter we describe a research approach and program that can begin to span this gap by using genome-enabled approaches to characterize organismal changes and then employing a genetically tractable model organism to …

Model Complexity Affects Transient Population Dynamics Following A Dispersal Event: A Case Study With Pea Aphids, Brigitte Tenhumberg, Andrew J. Tyre, Richard Rebarber

School of Biological Sciences: Faculty Publications

Stage-structured population models predict transient population dynamics if the population deviates from the stable stage distribution. Ecologists’ interest in transient dynamics is growing because populations regularly deviate from the stable stage distribution, which can lead to transient dynamics that differ significantly from the stable stage dynamics. Because the structure of a population matrix (i.e., the number of life-history stages) can influence the predicted scale of the deviation, we explored the effect of matrix size on predicted transient dynamics and the resulting amplification of population size. First, we experimentally measured the transition rates between the different life-history stages and the adult …

Animal Helminths In Human Archaeological Remains: A Review Of Zoonoses In The Past, Luciana Sianto, Marcia Chame, Cassius S. P. Silva, Marcelo L. C. Gonçalves, Karl Reinhard, Martín Horacio Fugassa, Adauto Araújo

Karl Reinhard Publications

The authors present a review of records of intestinal parasitic helminths from animals in human archaeological remains, reported since the emergence of paleopathological studies. The objective was to relate paleoparasitological findings to geographic, biotic, and abiotic factors from the environment in which the prehistoric populations lived, and understand some aspects related to the process of human dispersion and biological and cultural evolution. Modification of eating habits and the incorporation of new cultural practices are analyzed from the perspective of zoonoses from prehistory to the present day, especially in Brazilian indigenous populations. Three tables identifying the helminths, their natural hosts, dates, …

Ancient Leishmaniasis In A Highland Desert Of Northern Chile, Maria Antonietta Costa, Carney Matheson, Lucia Iachetta, Otto Appenzeller

Harold W. Manter Laboratory: Library Materials

Background

Leishmaniasis is an infectious disease endemic today in many areas of South America.

Methodology

We discovered morphologic and molecular evidence of ancient infections in four female skulls in the archaeological cemetery of Coyo Oriente, in the desert of San Pedro de Atacama, northern Chile. The boney facial lesions visible in the skulls could have been caused by a number of chronic infections including chronic Leishmaniasis. This diagnosis was confirmed using PCR-sequenced analyses of bone fragments from the skulls of the affected individuals. Leishmaniasis is not normally found in the high-altitude desert of northern Chile; where the harsh climate does …

Taxonomic Information Exchange And Copyright: The Plazi Approach, Donat Agosti, Willi Egloff

Harold W. Manter Laboratory: Library Materials

Background

A large part of our knowledge on the world's species is recorded in the corpus of biodiversity literature with well over hundred million pages, and is represented in natural history collections estimated at 2–3 billion specimens. But this body of knowledge is almost entirely in paper-print form and is not directly accessible through the Internet. For the digitization of this literature, new territories have to be chartered in the fields of technical, legal and social issues that presently impede its advance. The taxonomic literature seems especially destined for such a transformation.

Discussion

Plazi was founded as an association with …

A Redescription Of Three Species Of Monoecocestus (Cestoda: Anoplocephalidae) Including Monoecocestus Threlkeldi Based On New Material, Terry R. Haverkost, Scott Lyell Gardner

Scott L. Gardner Publications

Because we have new and detailed data on species in the genus, herein we redescribe both Monoecocestus macrobursatus and M. minor based on existing museum specimens. We also redescribe M. threlkeldi (Parra, 1952) using material collected in Bolivia. Based on the specimens representing M. thelkeldi, we affirm that Perutaenia Parra, 1953 should remain a junior synonym of Monoecocestus.

A Serological Survey Of Infectious Disease In Yellowstone National Park’S Canid Community, Emily S. Almberg, L. David Mech, Douglas W. Smith, Jennifer W. Sheldon, Robert L. Crabtree

USGS Northern Prairie Wildlife Research Center

Background: Gray wolves (Canis lupus) were reintroduced into Yellowstone National Park (YNP) after a .70 year absence, and as part of recovery efforts, the population has been closely monitored. In 1999 and 2005, pup survival was significantly reduced, suggestive of disease outbreaks.

Methodology/Principal Findings: We analyzed sympatric wolf, coyote (Canis latrans), and red fox (Vulpes vulpes) serologic data from YNP, spanning 1991–2007, to identify long-term patterns of pathogen exposure, identify associated risk factors, and examine evidence for disease-induced mortality among wolves for which there were survival data. We found high, constant exposure to canine …