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Boswell, NE, United States

Doane College is a private liberal arts college in Crete, Nebraska, United States, with additional campuses located in Lincoln, Grand Island and Omaha. Wikipedia.

Durham Brooks T.L.,University of Wisconsin - Madison | Durham Brooks T.L.,Doane College | Miller N.D.,University of Wisconsin - Madison | Spalding E.P.,University of Wisconsin - Madison
Plant Physiology | Year: 2010

Plant development is genetically determined but it is also plastic, a fundamental duality that can be investigated provided large number of measurements can be made in various conditions. Plasticity of gravitropism in wild-type Arabidopsis (Arabidopsis thaliana) seedling roots was investigated using automated image acquisition and analysis. A bank of computer-controlled charge-coupled device cameras acquired images with high spatiotemporal resolution. Custom image analysis algorithms extracted time course measurements of tip angle and growth rate. Twenty-two discrete conditions defined by seedling age (2, 3, or 4 d), seed size (extra small, small, medium, or large), and growth medium composition (simple or rich) formed the condition space sampled with 1,216 trials. Computational analyses including dimension reduction by principal components analysis, classification by k-means clustering, and differentiation by wavelet convolution showed distinct response patterns within the condition space, i.e. response plasticity. For example, 2-d-old roots (regardless of seed size) displayed a response time course similar to those of roots from large seeds (regardless of age). Enriching the growth medium with nutrients suppressed response plasticity along the seed size and age axes, possibly by ameliorating a mineral deficiency, although analysis of seeds did not identify any elements with low levels on a per weight basis. Characterizing relationships between growth rate and tip swing rate as a function of condition cast gravitropism in a multidimensional response space that provides new mechanistic insights as well as conceptually setting the stage for mutational analysis of plasticity in general and root gravitropism in particular. © 2009 American Society of Plant Biologists. Source

Elwell A.L.,Morgridge Institute for Research | Gronwall D.S.,University of Wisconsin - Madison | Miller N.D.,University of Wisconsin - Madison | Spalding E.P.,University of Wisconsin - Madison | Durham Brooks T.L.,Doane College
Plant, Cell and Environment | Year: 2011

Plant growth and development is profoundly influenced by environmental conditions that laboratory experimentation typically attempts to control. However, growth conditions are not uniform between or even within laboratories and the extent to which these differences influence plant growth and development is unknown. Experiments with wild-type Arabidopsis thaliana were designed to quantify the influences of parental environment and seed size on growth and development in the next generation. A single lot of seed was planted in six environmental chambers and grown to maturity. The seed produced was mechanically sieved into small and large size classes then grown in a common environment and subjected to a set of assays spanning the life cycle. Analysis of variance demonstrated that seed size effects were particularly significant early in development, affecting primary root growth and gravitropism, but also flowering time. Parental environment affected progeny germination time, flowering and weight of seed the progeny produced. In some cases, the parental environment affected the magnitude of (interacted with) the observed seed size effects. These data indicate that life history circumstances of the parental generation can affect growth and development throughout the life cycle of the next generation to an extent that should be considered when performing genetic studies. © 2010 Blackwell Publishing Ltd. Source

Choi J.K.,University of Wyoming | Sargsyan G.,University of Wyoming | Shabbir-Hussain M.,University of Wyoming | Holmes A.E.,Doane College | Balaz M.,University of Wyoming
Journal of Physical Chemistry B | Year: 2011

Here, we report a highly sensitive and specific chiroptical detection method of condensed left-handed Z-DNA in the presence of canonical right-handed B-DNA. The selective formation of a left-handed cytosine - guanine oligonucleotide (CG ODN) in the presence of a right-handed adenine - thymine oligonucleotide (AT ODN) was induced by millimolar concentrations of NiCl 2 and confirmed by electronic circular dichroism. The nickel(II) induced B- to Z-DNA transition of the CG ODN was accompanied by the concurrent condensation of the Ni(II)-Z-DNA, as confirmed by resonance light scattering, transmission spectroscopy, and centrifugation. The selective condensation of the CG ODN allowed its separation from the AT ODN using centrifugation. No structural changes were observed for the AT ODN upon addition of Ni(II). Anionic nickel(II) meso-tetra(4-sulfonatophenyl) porphyrin (NiTPPS) spectroscopically detected the left-handed Z-DNA in the Z-DNA/B-DNA mixture via a strong exciton coupled circular dichroism (ECCD) signal induced in the porphyrin Soret band absorption region. The bisignate ECCD signal originates from the assembly of achiral porphyrins into helical arrays by intermolecular interactions with the condensed Z-DNA scaffold. No induced CD signal was observed for the Ni(II)-B-DNA-NiTPPS complex. Hence, an unambiguous spectroscopic recognition of Ni(II) induced condensed Z-DNA in the presence of B-DNA is possible. The sensitivity of this chiroptical method was as low as 5% of the Z-DNA (4.4 μmol base pair concentration) in the presence of 95% B-DNA (80 μmol). Thus, NiTPPS is a highly sensitive probe for applications in biosensing via the CD signal amplification. © 2011 American Chemical Society. Source

Laungani R.,Doane College | Knops J.M.H.,University of Nebraska - Lincoln
Oikos | Year: 2012

In many terrestrial ecosystems nitrogen (N) limits productivity and plant community composition is influenced by N availability. However, vegetation is not only controlled by N; plant species may influence ecosystem N dynamics through positive or negative effects on N cycling. We examined four potential mechanisms of plant species effects on nitrogen (N) cycling. We found no species differences in gross ammonification suggesting there are no changes in the ecosystem N cycling rate between the soil organic matter pool (SOM) and the plant/microbial pool. We also found weak differences among plant species in gross nitrification, thus plant species only marginally change the relative sizes of the NH 4 + and NO 3 - pools. Next, more than 90% of mineralized N was microbially immobilized, and microbial N immobilization was positively correlated with root biomass. Finally, while species differed in extractable soil NO3 - concentration, these differences were not related to root biomass suggesting that microbial immobilization drives net N mineralization and soil NO 3 - levels. Our results indicate that plant species do not cause feedbacks on the N cycling rate among the three major ecosystem N pools over nine years. However, plant carbon (C) inputs to the soil control microbial N immobilization and thereby change N partitioning between the plant and microbial N pools. Furthermore our results suggest that the SOM pool can act as a strong bottleneck for N cycling in these systems. © 2012 The Authors. Oikos © 2012 Nordic Society Oikos. Source

Moteki S.A.,University of Nebraska - Lincoln | Moteki S.A.,Kyoto University | Toyama K.,University of Nebraska - Lincoln | Liu Z.,Nanjing University | And 3 more authors.
Chemical Communications | Year: 2012

Systematic changes, first to the structure of the catalyst scaffold and then to the ligating groups, are used to fine tune supramolecular catalysts to achieve high regioselectivity (95-98%) and high enantioselectivity (94-97% ee) across a series of meta-substituted styrenes varying in electronic character. Source

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