An Analysis of Hardwood Log Grading Systems in the Appalachian Region

This study identifies and describes various hardwood log grading systems historically used by the hardwood industry in the United States through a comprehensive literature review and analysis. Additionally, an industry sector survey (Appendix A) was designed and conducted to identify current log hardwood grading systems. Finally, based on the survey data, an analysis of the practices and techniques currently used for scaling and grading Appalachian hardwood logs is presented and discussed. In the first component of the study, books, journal articles, and papers pertaining to log grading are sorted and broached chronologically by the publication date and then separated into three chronological categories and review. Short summary abstracts of these studies are presented to briefly describe key findings of that study. In the second phase of the study, the results of a focused survey of hardwood sawmills, log yards, and other wood product producers in the Appalachian region is presented to profile current hardwood log grading and scaling practices. The survey consists of 18 major questions and eight sub-questions designed to characterize current scaling and grading practices used by the forest products industry in Appalachia (Appendix A). Survey results are summarized and analyzed to produce a statistical analysis of the current grading systems used by responding wood product producers. The results will be used to identify the commonly used hardwood log grading and scaling practices. Information developed from this study could be used as a means for the identification of barriers within the industry to a standardized log grading and scaling system. Ultimately, once the barriers are identified and addressed, the data could be used to develop scaling and grading protocols for anew hardwood log grading and system

In-situ measurements of oxygen, carbon monoxide and greenhouse gases from Ochsenkopf tall tower in Germany

We present 2.5 years (from June 2006 to December 2008) of in-situ measurements of CO2, O2, CH4, CO, N2O and SF6 mixing ratios sampled from 23, 90 and 163m above ground on the Ochsenkopf tower in the Fichtelgebirge range, Germany (50?0104900 N, 11?4803000 E, 1022ma.s.l.). In addition to the in-situ measurements, flask samples are taken at Ochsenkopf at approximately weekly intervals and are subsequently analysed for the mixing ratios of the same species, as well as H2, and the stable isotopes, ?13C, ?18O in CO2. The in-situ measurements of CO2 and O2 from 23m show substantial diurnal variations that are modulated by biospheric fluxes, combustion of fossil fuels, and by diurnal changes in the planetary boundary layer height. Measurements from 163m exhibit only very weak diurnal variability, as this height (1185ma.s.l.) is generally above the nocturnal boundary layer. CH4, CO, N2O and SF6 show little diurnal variation even at 23m owing to the absence of any significant diurnal change in the fluxes and the absence of any strong local sources or sinks. From the in-situ record, the seasonal cycles of the gas species have been characterized and the multi-annual trends determined. Because the record is short, the calculation of the trend is sensitive to inter-annual variations in the amplitudes of the seasonal cycles. However, for CH4 a significant change in the growth-rate was detected for 2006.5–2008.5 as compared with the global mean from 1999 to 2006 and is consistent with other recent observations of a renewed increasing global growth rate in CH4 since the beginning of 2007

Loop B is a major structural component of the 5-HT3 receptor

The 5-HT3 receptor belongs to a family of therapeutically important neurotransmitter-gated receptors whose ligand binding sites are formed by the convergence of six peptide loops (A-F). Here we have mutated 15 amino acid residues in and around loop B of the 5-HT3 receptor (Ser-177 to Asn-191) to Ala or a residue with similar chemical properties. Changes in [3H]granisetron binding affinity (Kd) and 5-HT EC50 were determined using receptors expressed in human embryonic kidney 293 cells. Substitutions at all but one residue (Thr-181) altered or eliminated binding for one or both mutants. Receptors were nonfunctional or EC50 values were altered for all but two mutants (S182T, I190L). Homology modeling indicates that loop B contributes two residues to a hydrophobic core that faces into the β-sandwich of the subunit, and the experimental data indicate that they are important for both the structure and the function of the receptor. The models also show that close to the apex of the loop (Ser-182 to Ile-190), loop B residues form an extensive network of hydrogen bonds, both with other loop B residues and with adjacent regions of the protein. Overall, the data suggest that loop B has a major role in maintaining the structure of the region by a series of noncovalent interactions that are easily disrupted by amino acid substitutions

The Wave Properties of Coronal Bright Fronts Observed Using SDO/AIA

Coronal bright fronts (CBFs) are large scale wavefronts that propagate though the solar corona at hundreds of kilometers per second. While their kinematics have been studied in detail, many questions remain regarding the temporal evolution of their amplitude and pulse width. Here, contemporaneous high cadence, multi-thermal observations of the solar corona from the Solar Dynamic Observatory (SDO) and Solar TErrestrial RElations Observatory (STEREO) spacecraft are used to determine the kinematics and expansion rate of a CBF wavefront observed on 2010 August 14. The CBF was found to have a lower initial velocity with weaker deceleration in STEREO observations compared to SDO (~340 km/s and -72 m/s/s as opposed to ~410 km/s and -279 m/s/s). The CBF kinematics from SDO were found to be highly passband-dependent, with an initial velocity ranging from 379+/-12 km/s to 460+/-28 km/s and acceleration ranging from -128+/-28 m/s/s to -431+/-86 m/s/s in the 335A and 304A passbands respectively. These kinematics were used to estimate a quiet coronal magnetic field strength range of ~1-2 G. Significant pulse broadening was also observed, with expansion rates of ~130 km/s (STEREO) and ~220 km/s (SDO). By treating the CBF as a linear superposition of sinusoidal waves within a Gaussian envelope, the resulting dispersion rate of the pulse was found to be ~8-13 Mm^2 s^-1. These results are indicative of a fast-mode magnetoacoustic wave pulse propagating through an inhomogeneous medium.Comment: 14 pages, 2 figures. Accepted for publication in The Astrophysical Journal Letter

Searching for the Magnetic Interactions in the Rare Earth Pyrochlore Oxide Yb₂Ti₂O₇

Various experiments on Yb₂Ti₂O₇ have shown evidence of strange magnetic behaviour at low temperatures. Specific heat measurements on powder samples of Yb₂Ti₂O₇ show evidence of a sharp peak, indicating the occurence of a first order phase transition. Meanwhile, neutron scattering, Mössbauer absorption, and μSR measurements find no evidence of long range order below the temperature of this phase transition, leaving the nature of the low temperature phase a mystery. Quantifying the magnetic interactions in this material should allow us to better understand the low temperature behaviour of this material. In this study, we fit a symmetry allowed nearest-neighbour bilinear exchange model to quasi-elastic neutron scattering data collected well above the temperature of the experimentally observed phase transition. This neutron scattering data shows evidence of rods of scattering intensity along the ⟨111⟩ crystallographic directions. Neutron scattering probes the correlations between magnetic moments in a material, so fitting an interaction model to the neutron scattering is equivalent to fitting the interactions to the magnetic correlations. These correlations are driven by the interactions between the magnetic moments, so the neutron scattering should give us direct access to the form of these interactions. Using this method we successfully identify an anisotropic nearest-neighbour bilinear exchange model that reproduces the experimentally observed quasi-elastic neutron scattering. With this model we then proceed to compute real space correlation functions, finding that the rods of neutron scattering arise from the presence of strong correlations along nearest-neighbour chains. We also compute the bulk susceptibility and local susceptibility, obtaining very good fits to experiment with no variation of the model determined from the neutron scattering. The success of these calculations provides a further independent confirmation of the success of our interaction model in describing the magnetic interactions in Yb₂Ti₂O₇. Finally, we present a brief summary of ongoing work based on our anisotropic exchange model, including mean field calculations to determine the low temperature ground state of this model and classical Monte Carlo simulations to study the phase transition present in this model. We also discuss potential further studies of this and other models

Family Legacies: Constructing Individual and Family Identity through Intergenerational Storytelling

The current study focused on discovering the ways in which the intergenerational transmission of family legacy stories both enables and constrains individual family members’ sense of their own identities. Using semistructured interviews, 17 third-generation family members identified a multitude of both positive and negative family legacies. Both positive and negative legacies were influenced by the storytelling context. Positive legacies portrayed families as hardworking, caring, and cohesive while negative legacies were more idiosyncratic. Individual family members typically responded to their family legacies by embracing the positive and rejecting the negative. However, individuals’ responses also pointed to additional complexities in accepting or rejecting family legacies. Specifically, some individuals embraced negative family legacies and rejected positive ones; others accepted only portions of the legacies; and some reported their legacies as unembraceable

Phase-resolved HST/STIS spectroscopy of the exposed white dwarf in the high-field polar AR UMa

Phase-resolved HST/STIS ultraviolet spectroscopy of the high-field polar AR UMa confirms that the WD photospheric Ly alpha Zeeman features are formed in a magnetic field of ~200 MG. In addition to the Ly alpha pi and sigma+ components, we detect the forbidden hydrogen 1s0->2s0 transition, which becomes ``enabled'' in the presence of both strong magnetic and electric fields. Our attempt in fitting the overall optical+UV low state spectrum with single temperature magnetic WD models remains rather unsatisfactory, indicating either a shortcoming in the present models or a new physical process acting in AR UMa. As a result, our estimate of the WD temperature remains somewhat uncertain, Twd=20000+-5000K. We detect a broad emission bump centered at ~1445A and present throughout the entire binary orbit, and a second bump near ~1650A, which appears only near the inferior conjunction of the secondary star. These are suggestive of low harmonic cyclotron emission produced by low-level (M-dot~1e-13 Msun/yr) accretion onto both magnetic poles. However, there is no evidence in the power spectrum of light variations for accretion in gas blobs. The observed Ly alpha emission line shows a strong phase dependence with maximum flux and redshift near orbital phase phi~0.3, strongly indicating an origin on the trailing hemisphere of the secondary star. An additional Ly alpha absorption feature with similar phasing as the Ly alpha emission, but a \~700km/s blueshift could tentatively be ascribed to absorption of WD emission in a moderately fast wind. We derive a column density of neutral hydrogen of NH=(1.1+-1.0)1e18 cm**-2, the lowest of any known polar.Comment: 26 pages, 10 figures, AAS TeX 5.0, accepted for publication in the Astrophysical Journa

Relationship Among Emotional Intelligence and/or Extrovert Bias on Perceived Stress Levels in DPT Students

Purpose/Hypothesis: Students in graduate level DPT programs function at varying levels. Some students thrive and others struggle to maintain required minimum levels of academic performance. When considering admission of applicants, and when assisting enrolled students, consideration of factors contributing to academic success is of interest. Stress has been shown to be prevalent in a wide range of students and has many negative effects including poor life satisfaction, increased clinical burnout, and reduced academic performance. Research has shown a correlation between higher emotional intelligence (EI) and decreased stress levels in medical, nursing, and undergraduate students. The purpose of this study was to examine if emotional intelligence (EI) and/or extrovert bias correlates with perceived stress levels in Doctor of Physical Therapy (DPT) students. It was hypothesized that students with higher emotional intelligence and more extroverted personalities would experience lower levels of perceived stress. Participants: After providing consent, a convenience sample of 60 first and second year DPT students (33 female) with age range 23 to 38 participated in the current study. Participation was voluntary and 60 of a possible 72 students chose to participate. Materials/Methods: After obtaining informed consent, participants completed Goldberg’s IPIP-Neo questionnaire (extraversion), Perceived Stress Scale (PSS) and Assessing Emotions Scale (emotional intelligence). Each of these tools have demonstrated validity and reliability for the respective areas measured. Surveys were administered to students and results were analyzed for possible relationships between extraversion and stress levels as well as EI and stress levels using a Spearman Correlation test. Results: Spearman Correlation analyses were conducted with a significant negative correlation between EI and perceived stress rs = -0.291, p= 0.026 and a non-significant negative correlation between extraversion and perceived stress rs = -1.36, p= 0.305. Discussion: In the current sample, EI had a significant negative relationship with perceived stress levels, with higher EI scores correlating to lower levels of stress. The relationship between extraversion and perceived stress was non-significant. Clinical Relevance: Doctorate level graduate programs can be considered intense and very stressful. Admission of qualified students equipped to meet the demands of a DPT program has great importance. Establishing a correlation between EI, introversion/extraversion bias, and stress may help DPT programs further assess prospective students. Consideration of factors correlated with higher perceived stress may be useful when providing resources to admitted students to facilitate academic success

Mass-Radius Relation for Magnetic White Dwarfs

Recently, several white dwarfs with very strong surface magnetic fields have been observed. In this paper we explore the possibility that such stars could have sufficiently strong internal fields to alter their structure. We obtain a revised white dwarf mass-radius relation in the presence of strong internal magnetic fields. We first derive the equation of state for a fully degenerate ideal electron gas in a magnetic field using an Euler-MacLaurin expansion. We use this to obtain the mass-radius relation for magnetic $^{4}$He, $^{12}$C, and $^{56}$Fe white dwarfs of uniform composition.Comment: 7 pages, 7 figures and 1 table, To appear in Ap