1,081 research outputs found

    Use of the Dominance Concept for Matching Raw Material Grades of Douglas-fir to Lumber Production Objectives

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    The concept of dominance, adopted from game theory, was applied to the problem of determining the most feasible Douglas-fir log grades for producing a given lumber product mix. Three sets of multiple objectives, representing three different broad categories of mills, were analyzed to assess how changes in the primary product mix affected the log buying and trading decisions. The mill categories examined were integrated mills producing both structural and nonstructural lumber, cutting mills producing nonstructural specialty lumber, and dimension mills producing structural lumber. In general, peeler log grades were most suitable for nonstructural lumber, while sawlogs were most suitable for structural lumber. Feasible log grades for the integrated mills included both peeler logs and sawlogs, but were predominantly second growth. Repeating the analyses with 1960 data indicated little change in log grade selections over time

    Back to basics- Are traditional teaching methods obsolete?

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    A survey requesting students to asses components of effective learning was presented in four forestry courses one at each undergraduate academic level. A total of 120 students received the survey and 118 returned it. Results clearly indicate that students rank instructor attitude and subject matter as the most significant factors to effective learning. Course style and format were much less important, although students have a clear preference for any format that provides hands-on experiences. While most students are familiar with some forms of teaching technology, they only rated it as somewhat effective to the learning process

    Stress Reduction Through Listening to Indian Classical Music During Gastroscopy

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    The purpose of this study was to examine the effects of music on elevated state of anxiety as many patients become stressed and anxious during diagnostic procedures. The study was conducted on 104 consecutive patients undergoing GI endoscopy for various reasons. Patients were randomly assigned to two groups regardless of sex, age and underlying disease. One group of 54 patients were made to listen to a recorded Indian classical instrumental music before and during the procedure, while the other group of 50 patients did not. Blood pressure, heart rate and respiratory rate were recorded at the beginning of consultation and end of procedure. Perception of procedure using a three point attitude scale was assessed. Our results indicate that the background Indian classical music is efficacious in reducing psychological distress during a gastroscopic examination. We suggest that music could be applied to other medical situations as well, which tend to generate undue psychological stress and anxiety. Music, as a familiar personal and culture medium, can be used to ease anxiety, to act as distractor, to increase discomfort and pain threshold

    Eigenmode Tomography of Surface Charge Oscillations of Plasmonic Nanoparticles by Electron Energy Loss Spectroscopy

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    Plasmonic devices designed in three dimensions enable careful tuning of optical responses for control of complex electromagnetic interactions on the nanoscale. Probing the fundamental characteristics of the constituent nanoparticle building blocks is, however, often constrained by diffraction-limited spatial resolution in optical spectroscopy. Electron microscopy techniques, including electron energy loss spectroscopy (EELS), have recently been developed to image surface plasmon resonances qualitatively at the nanoscale in three dimensions using tomographic reconstruction techniques. Here, we present an experimental realization of a distinct method that uses direct analysis of modal surface charge distributions to reconstruct quantitatively the three-dimensional eigenmodes of a silver right bipyramid on a metal oxide substrate. This eigenmode tomography removes ambiguity in two-dimensional imaging of spatially-localized plasmonic resonances, reveals substrate-induced mode degeneracy breaking in the bipyramid, and enables EELS for the analysis not of a particular electron-induced response but of the underlying geometric modes characteristic of particle surface plasmons.S.M.C. acknowledges support of a Gates Cambridge Scholarship. E.R. acknowledges support from the Royal Society's Newton International Fellowship scheme and a Trinity Hall Research Fellowship. We thank Ben Knappet for assistance with the synthesis of the silver bipyramids. We thank F.J. de la Peña for helpful discussions on the use of HYPERSPY. The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Program (No. FP7/2007-2013)/ERC Grant Agreement No. 291522-3DIMAGE and the European Union's Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483-ESTEEM2)This is the final version of the article. It was first available from ACS via http://dx.doi.org/10.1021/acsphotonics.5b0042

    Development of a High-Throughput Screening Assay Based on the 3-Dimensional Pannus Model for Rheumatoid Arthritis

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    Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.The 3-dimensional (3-D) pannus model for rheumatoid arthritis (RA) is based on the interactive co-culture of cartilage and synovial fibroblasts (SFs). Besides the investigation of the pathogenesis of RA, it can be used to analyze the active profiles of antirheumatic pharmaceuticals and other bioactive substances under in vitro conditions. For a potential application in the industrial drug-screening process as a transitional step between 2-dimensional (2-D) cell-based assays and in vivo animal studies, the pannus model was developed into an in vitro high-throughput screening (HTS) assay. Using the CyBi™-Disk workstation for parallel liquid handling, the main cell culture steps of cell seeding and cultivation were automated. Chondrocytes were isolated from articular cartilage and seeded directly into 96-well microplates in high-density pellets to ensure formation of cartilage-specific extracellular matrix (ECM). Cell seeding was performed automatically and manually to compare both processes regarding accuracy, reproducibility, consistency, and handling time. For automated cultivation of the chondrocyte pellet cultures, a sequential program was developed using the CyBio Control software to minimize shear forces and handling time. After 14 days of cultivation, the pannus model was completed by coating the cartilage pellets with a layer of human SFs. The effects due to automation in comparison to manual handling were analyzed by optical analysis of the pellets, histological and immunohistochemical staining, and real-time PCR. Automation of this in vitro model was successfully achieved and resulted in an improved quality of the generated pannus cultures by enhancing the formation of cartilage-specific ECM. In addition, automated cell seeding and media exchange increased the efficiency due to a reduction of labor intensity and handling time. (Journal of Biomolecular Screening 2007:956-965)BMBF, 0313604A, Verbundprojekt: Evaluierung eines interagierenden 3D Testsystems als Krankheitsmodell der rheumatoiden Arthritis (in vitro Pannus Modell) zur effektiven Prüfung von Wirkstoffen, Teilprojekt 1BMBF, 0313604B, Verbundprojekt: Entwicklung eines interagierenden 3D Testsystems als Krankheitsmodell der rheumatoiden Arthritis (in vitro Pannus Modell) zur effektiven Prüfung von Wirkstoffen, Teilprojekt

    Marked changes in electron transport through the blue copper protein azurin in the solid state upon deuteration

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    Measuring electron transport (ETp) across proteins in the solid-state offers a way to study electron transfer (ET) mechanism(s) that minimizes solvation effects on the process. Solid state ETp is sensitive to any static (conformational) or dynamic (vibrational) changes in the protein. Our macroscopic measurement technique extends the use of ETp meas-urements down to low temperatures and the concomitant lower current densities, because the larger area still yields measurable currents. Thus, we reported previously a surprising lack of temperature-dependence for ETp via the blue copper protein azurin (Az), from 80K till denaturation, while ETp via apo-(Cu-free) Az was found to be temperature de-pendent \geq 200K. H/D substitution (deuteration) can provide a potentially powerful means to unravel factors that affect the ETp mechanism at a molecular level. Therefore, we measured and report here the kinetic deuterium isotope effect (KIE) on ETp through holo-Az as a function of temperature (30-340K). We find that deuteration has a striking effect in that it changes ETp from temperature independent to temperature dependent above 180K. This change is expressed in KIE values between 1.8 at 340K and 9.1 at \leq 180K. These values are particularly remarkable in light of the previously reported inverse KIE on the ET in Az in solution. The high values that we obtain for the KIE on the ETp process across the protein monolayer are consistent with a transport mechanism that involves through-(H-containing)-bonds of the {\beta}-sheet structure of Az, likely those of am-ide groups.Comment: 15 pages, 3 figures, 2 Supplementary figure

    Generalized molecular solvation in non-aqueous solutions by a single parameter implicit solvation scheme

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    In computer simulations of solvation effects on chemical reactions, continuum modeling techniques regain popularity as a way to efficiently circumvent an otherwise costly sampling of solvent degrees of freedom. As effective techniques, such implicit solvation models always depend on a number of parameters that need to be determined earlier. In the past, the focus lay mostly on an accurate parametrization of water models. Yet, non-aqueous solvents have recently attracted increasing atten- tion, in particular, for the design of battery materials. To this end, we present a systematic parametrization protocol for the Self-Consistent Continuum Solvation (SCCS) model resulting in optimized parameters for 67 non-aqueous solvents. Our parametrization is based on a collection of ≈6000 experimentally measured partition coefficients, which we collected in the Solv@TUM database presented here. The accuracy of our optimized SCCS model is comparable to the well-known universal continuum solvation model (SMx) family of methods, while relying on only a single fit parameter and thereby largely reducing sta- tistical noise. Furthermore, slightly modifying the non-electrostatic terms of the model, we present the SCCS-P solvation model as a more accurate alternative, in particular, for aromatic solutes. Finally, we show that SCCS parameters can, to a good degree of accuracy, also be predicted for solvents outside the database using merely the dielectric bulk permittivity of the solvent of choice
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