5,829 research outputs found

    Healing Thyself: What Barriers Do Psychologists Face When Considering Personal Psychotherapy and How Can They Be Overcome?

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    Most mental health professionals seek personal psychotherapy at least once in their careers (Phillips, 2011), and at a much higher rate than the general population (Norcross & Guy, 2005). While one-fourth of the general adult population has received mental health services, three-fourths of mental health professionals have done so (Bike, Norcross, & Schatz, 2009; Norcross & Guy, 2005). A wealth of studies have explored why psychologists have sought personal psychotherapy — often for the same reason that the rest of the world seeks therapy, such as coping with loss, dealing with depression or anxiety, or struggling with a personal crisis. However, more research is needed about the potential barriers that psychologists may experience when considering such treatment. In this article, we discuss the research exploring why psychologists may benefit from psychotherapy and report on the findings of our own national survey, which explored independent practitioners\u27 perceived barriers to psychological care

    Breach of Posterior Wall of Frontal Sinus: Management with Preservation of the Sinus

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    ObjectiveTo analyze outcomes after the management of mild (<1 mm) and moderately severe (>1 mm and <5 mm) breaches of the posterior wall of the frontal sinus with a goal of maintaining or restoring the functional status of the sinus.MethodsA retrospective analysis of prospectively accrued data was performed on patients with mild and moderately severe breaches of the posterior wall of their frontal sinus who were managed with the intent to preserve the frontal sinus. Data on presenting features, pathology, details on breaches of the posterior wall, management, outcome, and complications were collected from medical records and neuroimages.ResultsForty-two cases met inclusion criteria. Diagnostic categories included trauma in 34 cases, infection in 3, and other categories in another 5 cases. Five presented with cerebrospinal fluid rhinorrhea, and 26 had radiographic evidence of obstruction of a nasofrontal duct at time of presentation. Fifteen patients were managed without surgical intervention, and 27 underwent surgery. No complications occurred in the patients managed without surgery and 4 postoperative cerebrospinal leaks that were managed successfully with a period of drainage occurred in the surgical group. No patient developed meningitis or mucocele.ConclusionsMany patients with mild to moderately severe breaches of the posterior wall of the frontal sinus can be managed safely and effectively by techniques that preserve the anatomy and function of the frontal sinus

    Future of the Virginia Oyster Industry

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    CHESAPEAKE BAY has long been famous for its oysters. Shared by Maryland and Virginia, this natural resource contributes greatly to the economic life of about thirty Tidewater counties. Virginia oyster grounds extend approximately half way up the bay and reach far up the numerous tributaries. In addition, there are thousands of acres of oyster grounds on the Sea Side of the Eastern Shore. Despite the magnitude of the acreage adapted for growing oysters, comparatively little effort has been made to find out just how valuable the industry is to the state or to explore its possibilities for development. Federal statistics indicate that Virginia ranks as the No. 1 oyster-producing state, the yield amounting to at least 5,000,000 bushels annually. Still, it is recognized that the state\u27s oyster grounds are capable of a much higher level of production than is witnessed toda

    Spitzer observations of Bow Shocks and Outflows in RCW 38

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    We report Spitzer observations of five newly identified bow shocks in the massive star-forming region RCW 38. Four are visible at IRAC wavelengths, the fifth is visible only at 24 microns. Chandra X-ray emission indicates that winds from the central O5.5 binary, IRS~2, have caused an outflow to the NE and SW of the central subcluster. The southern lobe of hot ionised gas is detected in X-rays; shocked gas and heated dust from the shock-front are detected with Spitzer at 4.5 and 24 microns. The northern outflow may have initiated the present generation of star formation, based on the filamentary distribution of the protostars in the central subcluster. Further, the bow-shock driving star, YSO 129, is photo-evaporating a pillar of gas and dust. No point sources are identified within this pillar at near- to mid-IR wavelengths. We also report on IRAC 3.6 & 5.8 micron observations of the cluster DBS2003-124, NE of RCW 38, where 33 candidate YSOs are identified. One star associated with the cluster drives a parsec-scale jet. Two candidate HH objects associated with the jet are visible at IRAC and MIPS wavelengths. The jet extends over a distance of ~3 pc. Assuming a velocity of 100 km/s for the jet material gives an age of about 30,000 years, indicating that the star (and cluster) are likely to be very young, with a similar or possibly younger age than RCW 38, and that star formation is ongoing in the extended RCW 38 region.Comment: 27 pages, 6 figures, accepted to Ap

    Semileptonic Decays of Heavy Lambda Baryons in a Quark Model

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    The semileptonic decays of Lambda_c and Lambda_b are treated in the framework of a constituent quark model. Both nonrelativistic and semirelativistic Hamiltonians are used to obtain the baryon wave functions from a fit to the spectra, and the wave functions are expanded in both the harmonic oscillator and Sturmian bases. The latter basis leads to form factors in which the kinematic dependence on q^2 is in the form of multipoles, and the resulting form factors fall faster as a function of q^2 in the available kinematic ranges. As a result, decay rates obtained in the two models using the Sturmian basis are significantly smaller than those obtained using the harmonic oscillator basis. In the case of the Lambda_c, decay rates calculated using the Sturmian basis are closer to the experimentally reported rates. However, we find a semileptonic branching fraction for the Lambda_c to decay to excited Lambda* states of 11% to 19%, in contradiction with what is assumed in available experimental analyses. Our prediction for the Lambda_b semileptonic decays is that decays to the ground state Lambda_c provide a little less than 70% of the total semileptonic decay rate. For the decays Lambda_b to Lambda_c, the analytic form factors we obtain satisfy the relations expected from heavy-quark effective theory at the non-recoil point, at leading and next-to-leading orders in the heavy-quark expansion. In addition, some features of the heavy-quark limit are shown to naturally persist as the mass of the heavy quark in the daughter baryon is decreased.Comment: 51 pages, 8 figures, submitted to Physical Review

    Ant colony optimisation and local search for bin-packing and cutting stock problems

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    The Bin Packing Problem and the Cutting Stock Problem are two related classes of NP-hard combinatorial optimization problems. Exact solution methods can only be used for very small instances, so for real-world problems, we have to rely on heuristic methods. In recent years, researchers have started to apply evolutionary approaches to these problems, including Genetic Algorithms and Evolutionary Programming. In the work presented here, we used an ant colony optimization (ACO) approach to solve both Bin Packing and Cutting Stock Problems. We present a pure ACO approach, as well as an ACO approach augmented with a simple but very effective local search algorithm. It is shown that the pure ACO approach can compete with existing evolutionary methods, whereas the hybrid approach can outperform the best-known hybrid evolutionary solution methods for certain problem classes. The hybrid ACO approach is also shown to require different parameter values from the pure ACO approach and to give a more robust performance across different problems with a single set of parameter values. The local search algorithm is also run with random restarts and shown to perform significantly worse than when combined with ACO

    Satellite laser ranging work at the Goddard Space Flight Center

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    Laser ranging systems, their range and accuracy capabilities, and planned improvements for future systems are discussed, the systems include one fixed and two mobile lasers ranging systems. They have demonstrated better than 10 cm accuracy both on a carefully surveyed ground range and in regular satellite ranging operations. They are capable of ranging to all currently launched retroreflector equipped satellites with the exception of Timation III. A third mobile system is discussed which will be accurate to better than 5 cm and will be capable of ranging to distant satellites such as Timation III and LAGEOS

    The Structure of the Star-forming Cluster RCW 38

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    We present a study of the structure of the high mass star-forming region RCW~38 and the spatial distribution of its young stellar population. Spitzer IRAC photometry 3-8um are combined with 2MASS near-IR data to identify young stellar objects by IR-excess emission from their circumstellar material. Chandra X-ray data are used to identify class III pre-main sequence stars lacking circumstellar material. We identify 624 YSOs: 23 class 0/I and 90 flat spectrum protostars, 437 Class II stars, and 74 Class III stars. We also identify 29 (27 new) O star candidates over the IRAC field. Seventy-two stars exhibit IR-variability, including seven class 0/I and 12 flat spectrum YSOs. A further 177 tentative candidates are identified by their location in the IRAC [3.6] vs. [3.6]-[5.8] cmd. We find strong evidence of subclustering in the region. Three subclusters were identified surrounding the central cluster, with massive and variable stars in each subcluster. The central region shows evidence of distinct spatial distributions of the protostars and pre-main sequence stars. A previously detected IR cluster, DB2001_Obj36, has been established as a subcluster of RCW 38. This suggests that star formation in RCW 38 occurs over a more extended area than previously thought. The gas to dust ratio is examined using the X-ray derived hydrogen column density, N_H and the K-band extinction, and found to be consistent with the diffuse ISM, in contrast with Serpens & NGC1333. We posit that the high photoionising flux of massive stars in RCW 38 affects the agglomeration of the dust grains.Comment: 98 pages, 15 figure

    Spitzer Observations of NGC 1333: A Study of Structure and Evolution in a Nearby Embedded Cluster

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    We present a comprehensive analysis of structure in the young, embedded cluster, NGC 1333 using members identified with Spitzer and 2MASS photometry based on their IR-excess emission. In total, 137 members are identified in this way, composed of 39 protostars and 98 more evolved pre-main sequence stars with disks. Of the latter class, four are transition/debris disk candidates. The fraction of exposed pre-main sequence stars with disks is 83% +/- 11%, showing that there is a measurable diskless pre-main sequence population. The sources in each of the Class I and Class II evolutionary states are shown to have very different spatial distributions relative to the distribution of the dense gas in their natal cloud. However, the distribution of nearest neighbor spacings among these two groups of sources are found to be quite similar, with a strong peak at spacings of 0.045 pc. Radial and azimuthal density profiles and surface density maps computed from the identified YSOs show that NGC 1333 is elongated and not strongly centrally concentrated, confirming previous claims in the literature. We interpret these new results as signs of a low velocity dispersion, extremely young cluster that is not in virial equilibrium.Comment: 59 pages, 20 figures, accepted to ApJ, verion with full resolution figures available at http://www.cfa.harvard.edu/~rgutermuth/preprints/gutermuth_ngc1333.pdf . Updated to fix astro-ph figure garblin
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