220 research outputs found

    Effects of Selenium on the Freshwater Alga Chlamydomonas reinhardtii with and Without the Proteasome Inhibitor MG132

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    Selenium is a required nutrient in animal life but has not been shown to be needed in plants. The model plant cell Chlamydomonas reinhardtii may be an exception as it appears to increase its growth rate in the presence of selenium. Because selenium has the same valence state as sulfur it may be incorporated into proteins as the modified amino acid selenocysteine. This incorporation of selenocysteine into protein may disrupt the disulfide bridges that give proteins the correct conformation. Misfolded proteins can wreak havoc on a cell. This stress can be measured through several parameters. Chlorophyll levels, glutathione levels, growth, and peroxidized lipid levels are just a few things that could be affected. This study is interested in the affects selenium has on those levels, and how they are affected when the proteasome is inhibited

    EC64-161 Common Range Plants in Nebraska

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    Extension Circular 64-161 This circular is about range plants in Nebraska. It describes their importance as well as some of the common range plants found in the state

    Factors Affecting the Chemical Composition of Range Forage Plants on the Edwards Plateau.

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    From Shared Governance to Shared Leadership: Our COVID Response to Faculty Evaluation, Support, and Advancement

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    As a state comprehensive university in a small, midwestern metropolitan area, “Students First” is more than a slogan. The preamble to our Faculty Constitution and our University’s mission statement both specify that students and their flourishing are the justification for our institution’s existence. We have learned, however, that a precondition to robust attention to students’ well-being is parallel attention to the well-being and development of our faculty. This article chronicles the principles and practices by which our shared leadership team responded to unique challenges presented by the COVID crisis and its ripple effects. A closing theme acknowledges that COVID revealed latent, pre-existing gaps in our care for faculty and students as well as introducing new and temporary challenges, and that some of our resulting solutions may require institutionalization as permanent fixtures

    Minimum Specific Energy and Critical Flow Conditions in Open Channels

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    In open channels, the relationship between the specific energy and the flow depth exhibits a minimum, and the corresponding flow conditions are called critical flow conditions. Herein they are re-analysed on the basis of the depth-averaged Bernoulli equation. At critical flow, there is only one possible flow depth, and a new analytical expression of that characteristic depth is developed for ideal-fluid flow situations with non-hydrostatic pressure distribution and non-uniform velocity distribution. The results are applied to relevant critical flow conditions : e.g., at the crest of a spillway. The finding may be applied to predict more accurately the discharge on weir and spillway crests

    Introducing Originality and Innovation in Engineering Teaching: The Hydraulic Design of Culverts

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    Recently the teaching of engineering design has become a presentation of standards and codes rather than the learning of sound design practices. Too many students request formulae and equations to solve a design exercise and they fail to develop any design originality. The present student attitude leads to young graduate engineers without critical ability and innovative flair. The writer has developed an innovative hydraulic design exercise based upon culvert design. Each design exercise could lead to more than one correct design per student in the class. Students have to learn basic design calculations based upon lecture material, notes, field visits and laboratory experiment. The practical component (laboratory, field visit) contributes significantly to their understanding of the complete system, including some basic safety and professional issues

    Unsteady Two-Dimensional Orifice Flow: A Large-Size Experimental Investigation

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    Orifice flows were used as water clocks since the Antiquity up to the 16-th century. Today orifices and nozzles are used for measuring discharges. Most works were conducted with steady flow conditions and there is little information on the unsteady flow pattern. In this study, the writers describe an experimental investigation of an unsteady orifice flow discharging vertically. The study was conducted in a large-size facility with a rectangular orifice (0.75-m by 0.07-m) discharging up to 1.2 m3 in about 10 seconds. The study presents new information on the unsteady flow patterns, the discharge capacity and the velocity field in the reservoir. The results are compared with 'classical' orifice flow results

    Hydraulic Performances of Minimum Energy Loss Culverts in Australia

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    Culverts are among the most common hydraulic structures. Modern designs do not differ from ancient structures and are often characterised by significant afflux at design flows. A significant advance was the development of the Minimum Energy Loss (MEL) culverts in the late 1950s. The design technique allows a drastic reduction in upstream flooding associated with lower costs. The development and operational performances of this type of structure is presented. The successful operation of MEL culverts for more than 40 years is documented with first-hand records during and after floods. The experiences demonstrate the design soundness while highlighting the importance of the hydraulic expertise of the design engineers
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