2,859 research outputs found

    Digital Preservation and Access of Natural Resources Documents

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    Digitization and preservation of natural resource documents were reviewed and the current status of digitization presented for a North American university. It is important to present the status of the digitation process for natural resources and to advocate for increased collections of digital material for ease of reference and exchange of information. Digital collections need to include both published documents and ancillary material for research projects and data for future use and interpretation. The methods in this paper can be applied to other natural resource collections increasing their use and distribution. The process of decision making for documents and their preservation and inclusion in ScholarWorks is presented as a part of the Forest Sciences Commons as a subset of the Life Sciences Commons of the Digital Commons Open Network launched and maintained by bepress. Digitization has increased the roles and skillsets needed for librarians and from libraries. This creates new challenges and opportunities for the library as publisher and as an advocate for open access. Digital curation melds together digitization and knowledge management and enhances community engagement. Digitization of collections are reviewed and natural resource documentation presented for faculty publications, Research Projects and Centers, eBooks, Journals, Galleries and electronic Theses and Dissertations (ETDs). Recommendations are made to increase the digital curation of the collection by encouraging community participation and use. Digital archives are important to natural resource professionals as society-ready natural resource graduates need to deal effectively with complex ecological, economic and social issues of current natural resources management. Natural resource research for the future needs to ensure that professionals have a greater breath of knowledge as they interpret and apply new knowledge, understanding, and technology to complex, transdisciplinary social and biological issues and challenges

    Basic mathematical programming applications to weed control in forestry

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    Many studies document herbicide performance for Heed and hardwood control in forestry. Few studies, hoHever, attemp t to develop optima l application strategies. Stand-level optindzation is presently limited due to lack of groHth and yield information. Forest-level optimization is possible, however, and has great potential to aid in planning forestry weed control prog rams

    Introduction to forestry investment analysis: Part I. Basic investment characteristics and financial criteria

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    Many forest landowners consider their forest to be an investment. Some of these landowners, however, and many new timberland investors, may not fully understand the basic ingredients that make up a forestry investment. Like all investments, forestry involves costs and revenues, and rates of return can be calculated. These rates of return can be compared with interest rates earned for other investments, but forest landowners should be sure to understand the unique characteristics of a forestry investment. Most of the cash flow from a forestry investment will result from timber sales. Timber sale revenue, of course, is a function of current stumpage prices, but also it is a function of the amount of wood removed from an acre. This is called forest yield

    Introduction to forestry investment analysis: Part II. Taxes, inflation, and other issues

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    Part I of this article covered the basics of compounding and discounting. You were introduced to forestry investment analysis. However, several complications were not discussed. What about inflation, taxes, and risk? Part II addresses basic complications. It also includes more detailed forestry investment analyses

    Implementation of Collaborative Learning as a High-Impact Practice in a Natural Resources Management Section of Freshman Seminar

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    Forestry and environmental science students enrolled in a one credit hour freshman seminar course participated in a land management evaluation and water quality sampling excursion using canoes and water sampling equipment. The purpose of this assessment was to engage students with hands-on, field based education in order to foster connections to their chosen profession and the resource. This culminated in poster symposium of the experience. Broad competency areas for high impact practices in natural resource management were emphasized for learning. Students were engaged in the exercise and commented that the project helped them develop a sense of place and forming connections within their peer group. The use of water quality sampling and collection of real-world data increased the teaching a learning effectiveness of the course

    The Sun's Preferred Longitudes and the Coupling of Magnetic Dynamo Modes

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    Observations show that solar activity is distributed non-axisymmetrically, concentrating at "preferred longitudes". This indicates the important role of non-axisymmetric magnetic fields in the origin of solar activity. We investigate the generation of the non-axisymmetric fields and their coupling with axisymmetric solar magnetic field. Our kinematic generation (dynamo) model operating in a sphere includes solar differential rotation, which approximates the differential rotation obtained by inversion of helioseismic data, modelled distributions of the turbulent resistivity, non-axisymmetric mean helicity, and meridional circulation in the convection zone. We find that (1) the non-axisymmetric modes are localised near the base of the convection zone, where the formation of active regions starts, and at latitudes around 30∘30^{\circ}; (2) the coupling of non-axisymmetric and axisymmetric modes causes the non-axisymmetric mode to follow the solar cycle; the phase relations between the modes are found. (3) The rate of rotation of the first non-axisymmetric mode is close to that determined in the interplanetary space.Comment: 22 pages, 18 figures. Accepted for publication in the Astrophysical Journa

    Low-Resistance Molecular Wires Propagate Spin-Polarized Currents

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    Spin based properties, applications, and devices are typically related to inorganic ferromagnetic materials. The development of organic materials for spintronic applications has long been encumbered by its reliance on ferromagnetic electrodes for polarized spin injection. The discovery of the chirality-induced spin selectivity (CISS) effect, in which chiral organic molecules serve as spin filters, defines a marked departure from this paradigm because it exploits soft materials, operates at ambient temperature, and eliminates the need for a magnetic electrode. To date, the CISS effect has been explored exclusively in molecular insulators. Here we combine chiral molecules, which serve as spin filters, with molecular wires that despite not being chiral, function to preserve spin polarization. Self-Assembled monolayers (SAMs) of right-handed helical (l-proline)8 (Pro8) and corresponding peptides, N-Terminal conjugated to (porphinato)zinc or meso-To-meso ethyne-bridged (porphinato)zinc structures (Pro8PZnn), were interrogated via magnetic conducting atomic force microscopy (mC-AFM), spin-dependent electrochemistry, and spin Hall devices that measure the spin polarizability that accompanies the charge polarization. These data show that chiral molecules are not required to transmit spin-polarized currents made possible by the CISS mechanism. Measured Hall voltages for Pro8PZn1-3 substantially exceed that determined for the Pro8 control and increase dramatically as the conjugation length of the achiral PZnn component increases; mC-AFM data underscore that measured spin selectivities increase with an increasing Pro8PZn1-3 N-Terminal conjugation. Because of these effects, spin-dependent electrochemical data demonstrate that spin-polarized currents, which trace their genesis to the chiral Pro8 moiety, propagate with no apparent dephasing over the augmented Pro8PZnn length scales, showing that spin currents may be transmitted over molecular distances that greatly exceed the length of the chiral moiety that makes possible the CISS effect

    Twisted molecular wires polarize spin currents at room temperature

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    A critical spintronics challenge is to develop molecular wires that render efficiently spin-polarized currents. Interplanar torsional twisting, driven by chiral binucleating ligands in highly conjugated molecular wires, gives rise to large near-infrared rotational strengths. The large scalar product of the electric and magnetic dipole transition moments ([Formula: see text]), which are evident in the low-energy absorptive manifolds of these wires, makes possible enhanced chirality-induced spin selectivity-derived spin polarization. Magnetic-conductive atomic force microscopy experiments and spin-Hall devices demonstrate that these designs point the way to achieve high spin selectivity and large-magnitude spin currents in chiral materials
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