303 research outputs found
Adjusting Cutter Numbers for Composers at the University of Southern Mississippi Libraries
In music cataloging, two primary methods are used for assigning Cutter numbers for composers. Some libraries maintain a list of composer Cutter numbers and then assign the same number to a composer in all music classes, i.e., Yale University’s Composer Cutter List at www.library.yale.edu/cataloging/music/cutter. Other libraries, including the Library of Congress, do not assign fixed Cutter numbers to individual composers, and are only consistent within single music classifications (Smiraglia 2008). There are advantages and disadvantages to the use of fixed Cutter numbers. Catalogers tend to memorize the numbers for major composers. This saves time as catalogers do not have to check the shelflist to find the specific number for a composer within a music class. A disadvantage is that some Cutter numbers would tend to become long (over three digits) due to the need to allow for the possibility of numerous composers with similar names and to keep their Cutters consistent from class number to class number
Metrics that matter for assessing the ocean biological carbon pump
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Buesseler, K. O., Boyd, P. W., Black, E. E., & Siegel, D. A. Metrics that matter for assessing the ocean biological carbon pump. Proceedings of the National Academy of Sciences of the United States of America, (2020): 201918114, doi: 10.1073/pnas.1918114117.The biological carbon pump (BCP) comprises wide-ranging processes that set carbon supply, consumption, and storage in the oceans’ interior. It is becoming increasingly evident that small changes in the efficiency of the BCP can significantly alter ocean carbon sequestration and, thus, atmospheric CO2 and climate, as well as the functioning of midwater ecosystems. Earth system models, including those used by the United Nation’s Intergovernmental Panel on Climate Change, most often assess POC (particulate organic carbon) flux into the ocean interior at a fixed reference depth. The extrapolation of these fluxes to other depths, which defines the BCP efficiencies, is often executed using an idealized and empirically based flux-vs.-depth relationship, often referred to as the “Martin curve.” We use a new compilation of POC fluxes in the upper ocean to reveal very different patterns in BCP efficiencies depending upon whether the fluxes are assessed at a fixed reference depth or relative to the depth of the sunlit euphotic zone (Ez). We find that the fixed-depth approach underestimates BCP efficiencies when the Ez is shallow, and vice versa. This adjustment alters regional assessments of BCP efficiencies as well as global carbon budgets and the interpretation of prior BCP studies. With several international studies recently underway to study the ocean BCP, there are new and unique opportunities to improve our understanding of the mechanistic controls on BCP efficiencies. However, we will only be able to compare results between studies if we use a common set of Ez-based metrics.We thank the many scientists whose ideas and contributions over the years are the foundation of this paper. This includes A. Martin, who led the organization of the BIARRITZ group (now JETZON) workshop in July 2019, discussions at which helped to motivate this article. We thank D. Karl for pointing us in the right direction for this paper format at PNAS and two thoughtful reviewers who through their comments helped to improve this manuscript. Support for writing this piece is acknowledged from several sources, including the Woods Hole Oceanographic Institution’s Ocean Twilight Zone project (K.O.B.); NASA as part of the EXport Processes in the global Ocean from RemoTe Sensing (EXPORTS) program (K.O.B. and D.A.S.). E.E.B. was supported by a postdoctoral fellowship through the Ocean Frontier Institute at Dalhousie University. P.W.B. was supported by the Australian Research Council through a Laureate (FL160100131)
Phase I and II enzyme induction and inhibition by secoisolariciresinol diglucoside and it's aglycone
The flaxseed lignan, secoisolariciresinol diglucoside (SDG), and its aglycone, secoisolariciresinol (SECO), have demonstrated benefits in the treatment and/or prevention of cancer, diabetes and cardiovascular disease. In order for the lignans to be used therapeutically, the safety of administration alone and in conjunction with other drugs must be determined. The primary cause of drug interactions is induction and inhibition of cytochrome P450 (CYP) and phase II enzymes. A preliminary screen was conducted to assess the potential for SECO and SDG to cause CYP inhibition. A method was established to assess for CYP, glutathione-S-transferase (GST) and uridine diphosphate-glucuronosyltransferase (UGT) induction in rat primary hepatocytes by real-time reverse transcription-polymerase chain reaction (RT-PCR).Preliminary assessments of inhibition measured the metabolism of testosterone to 6β-, 16α- and 2α-hydroxytestosterone, which corresponds to CYP3A, 2B/2C11 and 2C11 enzyme activity in rat hepatic microsomes by a validated high performance liquid chromatography (HPLC) method. Irreversible inhibition studies found that SDG is not an inhibitor of these isoforms up to 1000 μM. Secoisolariciresinol caused reversible inhibition of 6β-hydroxytestosterone at all testosterone concentrations, with an IC50 (inhibitor concentration causing 50% inhibition of enzyme) between 400 and 800 μM. Over the range of SECO concentrations tested, 10 – 1600 μM, 6β-hydroxytestosterone formation was reduced to 95 – 29% of control levels at 50 μM testosterone.Secoisolariciresinol caused a concentration-dependent increase in 16α-hydroxytestosterone formation at 50 μM testosterone. At 10 μM SECO, there was 90% of control activity, but at 1600 μM metabolite formation was 172% of control. The formation of 2α-hydroxytestosterone was not affected at any testosterone or inhibitor concentration. Thus, SECO appears to be a CYP3A inhibitor and a CYP2B activator at testosterone KM levels. The mechanism of reversible inhibition could not be determined due to the possibility of non-Michaelis-Menten kinetics observed with CYP3A inhibition and CYP2B activation. The gold standard in vitro model to assess induction is primary hepatocytes. A method was established that allowed for the isolation and culture of these cells. Positive controls caused induction of CYP mRNA levels after 24 hours treatment, demonstrating the ability of enzyme induction in the test system. Primers for real-time RT-PCR were designed that amplified CYP1A1, 1A2, 2B1, 2C11, 2C13, 2D1, 2D2, 3A1 and 3A2, GSTA2, A5 and P1, and UGT1A1, 1A7, 1A8, 2B1 and 2B12 genes. A preliminary assessment of transcriptional upregulation of drug metabolizing enzymes by SECO and SDG can be assessed in isolated and cultured rat primary hepatocytes
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Extracting the Density Profile of an Electronic Wave Function in a Quantum Dot
We use a model of a one-dimensional nanowire quantum dot to demonstrate the feasibility of a scanning probe microscope (SPM) imaging technique that can extract both the energy of an electron state and the amplitude of its wave function using a single instrument. This imaging technique can probe electrons that are buried beneath the surface of a low-dimensional semiconductor structure and provide valuable information for the design of quantum devices. A conducting SPM tip, acting as a movable gate, measures the energy of an electron state using Coulomb blockade spectroscopy. When the tip is close to the nanowire dot, it dents the wave function of the quantum state, changing the electron's energy by an amount proportional to . By recording the change in energy as the SPM tip is moved along the length of the dot, the density profile of the electronic wave function can be found along the length of the quantum dot.Engineering and Applied Science
Modeling Ablation of Charring Heat Shield Materials for Non-continuum Hypersonic Flow
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97121/1/AIAA2012-532.pd
Evaluation of Finite-Rate Surface Chemistry Models for Simulation of the Stardust Reentry Capsule
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97086/1/AIAA2012-2874.pd
Modeling of the Electric Field in a Hypersonic Rarefied Flow
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/83620/1/AIAA-2010-635-332.pd
Simulation of Reactions Involving Charged Particles in Hypersonic Rarefied Flows
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77265/1/AIAA-2009-267-646.pd
Concept Maps in the Family Science Classroom
This presentation will illustrate the usefulness and variability of concept maps in family science classrooms. This poster will define concept maps, demonstrate examples of effective use of concept maps in teaching family science, and delineate scholarly-based information on how to maximize their effectiveness. It also will illustrate the importance of student involvement in constructing and using this visual aid
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