790 research outputs found

    Assessing a forestry education: The Northern Arizona University experience

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    In an attempt to provide students with a strong generalist education, the faculty at Northern Arizona University\u27s School of Forestry has presented its undergraduate forestry education in a unique, integrated, team-taught approach for over 20 years. Over this same period of time, higher education has experienced profound changes. Within the discipline, the technical knowledge expected of undergraduates has expanded greatly. Simultaneously the demand for accountability in higher education has increased. Students, parents, state legislators, governing boards, and taxpayers alike have questioned the importance, relevance, and value of higher education. The so-called student-as-consumer model in higher education is but one manifestation of this increased demand for accountability. A fundamental question arises: How well does the forestry program at NAU prepare students educationally as foresters? Assessing student academic achievement with respect to educational outcomes provides one way of answering this question. Such a process can help determine how well students master a set of defined skills, knowledges, and competencies. Such an approach requires a defined set of desired educational outcomes

    How Children and Adults Make Judgments About Who To Trust

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    Beauty is Good Stereotype : Higher attractive individuals are thought to be more intelligent, more successful, and happier overall. They also obtain more visual attention and are deemed more trustworthy. Making a choice based on a person\u27s appearance and attributes might lead to dangerous consequences and lead to being deceived. We investigated how the appearance of male and female experts influence whether children and adults trust statements made by the expert, establish what that expert knows and determine that expert\u27s attributes (warmth and competence). The results of this study will help us better determine what cues children and adults use when making trustworthiness decisions.https://digitalscholarship.unlv.edu/durep_posters/1085/thumbnail.jp

    49Cr: Towards full spectroscopy up to 4 MeV

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    The nucleus 49Cr has been studied analysing gamma-gamma coincidences in the reaction 46Ti(alpha,n)49Cr at the bombarding energy of 12 MeV. The level scheme has been greatly extended at low excitation energy and several new lifetimes have been determined by means of the Doppler Shift Attenuation Method. Shell model calculations in the full pf configuration space reproduce well negative-parity levels. Satisfactory agreement is obtained for positive parity levels by extending the configuration space to include a nucleon-hole either in the 1d3/2 or in the 2s1/2 orbitals. A nearly one-to-one correspondence is found between experimental and theoretical levels up to an excitation energy of 4 MeV. Experimental data and shell model calculations are interpreted in terms of the Nilsson diagram and the particle-rotor model, showing the strongly coupled nature of the bands in this prolate nucleus. Nine values of K(pi) are proposed for the levels observed in this experiment. As a by-result it is shown that the values of the experimental magnetic moments in 1f7/2 nuclei are well reproduced without quenching the nucleon g-factors.Comment: 13 pages, 8 figure

    Lifetime measurements in 63^{63}Co and 65^{65}Co

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    Lifetimes of the 9/219/2^-_1 and 3/213/2^-_1 states in 63^{63}Co and the 9/219/2^-_1 state in 65^{65}Co were measured using the recoil distance Doppler shift and the differential decay curve methods. The nuclei were populated by multi-nucleon transfer reactions in inverse kinematics. Gamma rays were measured with the EXOGAM Ge array and the recoiling fragments were fully identified using the large-acceptance VAMOS spectrometer. The E2 transition probabilities from the 3/213/2^-_1 and 9/219/2^-_1 states to the 7/27/2^- ground state could be extracted in 63^{63}Co as well as an upper limit for the 9/217/219/2^-_1\rightarrow7/2^-_1 BB(E2) value in 65^{65}Co. The experimental results were compared to large-scale shell-model calculations in the pfpf and pfg9/2pfg_{9/2} model spaces, allowing to draw conclusions on the single-particle or collective nature of the various states.Comment: 8 pages, 8 figures, 1 table, accepted for publication in Physical Review

    Lifetime determination of excited states in Cd-106

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    Two separate experiments using the Differential Decay Curve Method have been performed to extract mean lifetimes of excited states in 106 Cd. The inedium-spin states of interest were populated by the Mo-98(C-12, 4n) Cd-106 reaction performed at the Wright Nuclear Structure Lab., Yale University. From this experiment, two isomeric state mean lifetimes have been deduced. The low-lying states were populated by the Mo-96(C-13, 3n)Cd-106 reaction performed at the Institut fur Kernphysik, Universitat zu Koln. The mean lifetime of the I-pi = 2(1)(+) state was deduced, tentatively, as 16.4(9) ps. This value differs from the previously accepted literature value from Coulomb excitation of 10.43(9) ps

    Hard X-ray Imaging for Measuring Laser Absorption Spatial Profiles on the National Ignition Facility

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    Hard x-ray (''Thin wall'') imaging will be employed on the National Ignition Facility (NIF) to spatially locate laser beam energy deposition regions on the hohlraum walls in indirect drive Inertial Confinement Fusion (ICF) experiments, relevant for ICF symmetry tuning. Based on time resolved imaging of the hard x-ray emission of the laser spots, this method will be used to infer hohlraum wall motion due to x-ray and laser ablation and any beam refraction caused by plasma density gradients. In optimizing this measurement, issues that have to be addressed are hard x-ray visibility during the entire ignition laser pulse with intensities ranging from 10{sup 13} to 10{sup 15} W/cm{sup 2}, as well as simultaneous visibility of the inner and the outer laser drive cones. In this work we will compare the hard x-ray emission calculated by LASNEX and analytical modeling with thin wall imaging data recorded previously on Omega and during the first hohlraum experiments on NIF. Based on these calculations and comparisons the thin wall imaging will be optimized for ICF/NIF experiments

    Electronic Structure and Vibrational Spectra of C2B10-Based Clusters and Films

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    The electronic structure, total energy, and vibrational properties of C2B10H12 (carborane)molecules and C2B10 clusters formed when the hydrogen atoms are removed from carborane molecules are studied using density functional methods and a semiempirical model. Computed vibrational spectra for carborane molecules are shown to be in close agreement with previously published measured spectra taken on carborane solids. Semiconducting boron carbide films are prepared by removing hydrogen from the three polytypes of C2B10H12 deposited on various surfaces. Results from x-ray and Raman scattering measurements on these films are reported. Eleven vibrationally stable structures for C2B10 clusters are described and their energies and highest occupied and lowest unoccupied molecular orbital gaps tabulated. Calculated Raman and infrared spectra are reported for the six lowest-energy clusters. Good agreement with the experimental Raman spectra is achieved from theoretical spectra computed using a Boltzmann distribution of the six lowest-energy free clusters. The agreement is further improved if the computed frequencies are scaled by a factor of 0.94, a descrepancy which could easily arise from comparing results of two different systems: zero-temperature free clusters and roomtemperature films. Calculated energies for removal of hydrogen pairs from carborane molecules are reported
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