7,988 research outputs found

    Electrical phase angle as a new method to measure fish condition

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    In this study, phase angle (the ratio of resistance and reactance of tissue to applied electrical current) is presented as a possible new method to measure fish condition. Condition indices for fish have historically been based on simple weight-at-length relationships, or on costly and timeconsuming laboratory procedures that measure specific physiological parameters. Phase angle is introduced to combine the simplicity of a quick field-based measurement with the specificity of laboratory analysis by directly measuring extra- and intracellular water distribution within an organism, which is indicative of its condition. Phase angle, which can be measured in the field or laboratory in the time it takes to measure length and weight, was measured in six species of fish at different states (e.g., fed vs. fasted, and postmortem) and under different environmental treatments (wild vs. hatchery, winter vs. spring). Phase angle reflected different states of condition. Phase angles 15° indicated fish that were in better condition. Phase angle was slightly affected by temperatures (slope = – 0.19) in the 0–8°C range and did not change in fish placed on ice for <12 hours. Phase angle also decreased over time in postmortem fish because of cell membrane degradation and subsequent water movement from intra- to extracellular (interstitial) spaces. Phase angle also reflected condition of specific anatomical locations within the fish

    A survey of quality control personnel in the Boston area March, 1955.

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    Thesis (M.B.A.)--Boston Universit

    Regional Regulation of Purkinje Cell Dendritic Spines by Integrins and Eph/Ephrins.

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    Climbing fibres and parallel fibres compete for dendritic space on Purkinje cells in the cerebellum. Normally, climbing fibres populate the proximal dendrites, where they suppress the multiple small spines typical of parallel fibres, leading to their replacement by the few large spines that contact climbing fibres. Previous work has shown that ephrins acting via EphA4 are a signal for this change in spine type and density. We have used an in vitro culture model in which to investigate the ephrin effect on Purkinje cell dendritic spines and the role of integrins in these changes. We found that integrins α3, α5 and β4 are present in many of the dendritic spines of cultured Purkinje cells. pFAK, the main downstream signalling molecule from integrins, has a similar distribution, although the intenstity of pFAK staining and the percentage of pFAK+ spines was consistently higher in the proximal dendrites. Activating integrins with Mg2+ led to an increase in the intensity of pFAK staining and an increase in the proportion of pFAK+ spines in both the proximal and distal dendrites, but no change in spine length, density or morphology. Blocking integrin binding with an RGD-containing peptide led to a reduction in spine length, with more stubby spines on both proximal and distal dendrites. Treatment of the cultures with ephrinA3-Fc chimera suppressed dendritic spines specifically on the proximal dendrites and there was also a decrease of pFAK in spines on this domain. This effect was blocked by simultaneous activation of integrins with Mn2+. We conclude that Eph/ephrin signaling regulates proximal dendritic spines in Purkinje cells by inactivating integrin downstream signalling

    Speckle observations with PISCO in Merate - V. Astrometric measurements of visual binaries in 2006

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    International audienceWe present relative astrometric measurements of visual binaries made during the first semester of 2006, with the Pupil Interferometry Speckle camera and COronagraph at the 102-cm Zeiss telescope of the Brera Astronomical Observatory, in Merate. Our sample contains orbital couples as well as binaries whose motion is still uncertain. We obtained 217 new measurements of 194 objects, with angular separations in the range 0.1-4.2arcsec, and an average accuracy of 0.01arcsec. The mean error on the position angles is 0.5°. About half of those angles could be determined without the usual 180° ambiguity by the application of triple-correlation techniques. We also present a revised orbit for ADS 277 for which the previously published orbit resulted in a large residual from our measurements

    Convergence and Psychometric Properties of Character Strengths Measures: The VIA-IS and the VIA-IS-R.

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    This study compares the German versions of the original measure of character strengths (VIA-IS) with its latest revision (VIA-IS-R) regarding reliability and convergent, discriminant, and criterion-related validity. A sample of 499 German-speaking adults (79% women, mean age: 33.3 years) provided self-reports of character strengths (VIA-IS, VIA-IS-R) and several criteria: Core virtues, thriving, and moral behaviors. Results suggested that both measures showed satisfactory internal consistency and converged well in a multitrait-multimethod analysis. Further, both measures were comparable regarding their relationships with the criteria. Overall, the results of the current study suggest that both questionnaires are reliable and valid, and that findings based on these instruments can be considered highly comparable

    The High Angular Resolution Multiplicity of Massive Stars

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    We present the results of a speckle interferometric survey of Galactic massive stars that complements and expands upon a similar survey made over a decade ago. The speckle observations were made with the KPNO and CTIO 4 m telescopes and USNO speckle camera, and they are sensitive to the detection of binaries in the angular separation regime between 0.03" and 5" with relatively bright companions (Delta V < 3). We report on the discovery of companions to 14 OB stars. In total we resolved companions of 41 of 385 O-stars (11%), 4 of 37 Wolf-Rayet stars (11%), and 89 of 139 B-stars (64%; an enriched visual binary sample that we selected for future orbital determinations). We made a statistical analysis of the binary frequency among the subsample that are listed in the Galactic O Star Catalog by compiling published data on other visual companions detected through adaptive optics studies and/or noted in the Washington Double Star Catalog and by collecting published information on radial velocities and spectroscopic binaries. We find that the binary frequency is much higher among O-stars in clusters and associations compared to the numbers for field and runaway O-stars, consistent with predictions for the ejection processes for runaway stars. We present a first orbit for the O-star Delta Orionis, a linear solution of the close, apparently optical, companion of the O-star Iota Orionis, and an improved orbit of the Be star Delta Scorpii. Finally, we list astrometric data for another 249 resolved and 221 unresolved targets that are lower mass stars that we observed for various other science programs.Comment: 76 pages, 6 figures, 11 table

    New high-sensitivity, milliarcsecond resolution results from routine observations of lunar occultations at the ESO VLT

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    (Abridged) Lunar occultations (LO) are a very efficient and powerful technique, that achieves the best combination of high angular resolution and sensitivity possible today at near-infrared wavelengths. Given that the events are fixed in time, that the sources are occulted randomly, and that the telescope use is minimal, the technique is very well suited for service mode observations. We have established a program of routine LO observations at the VLT observatory, especially designed to take advantage of short breaks available in-between other programs. We have used the ISAAC instrument in burst mode, capable of producing continuous read-outs at millisecond rates on a suitable subwindow. Given the random nature of the source selection, our aim has been primarily the investigation of a large number of stellar sources at the highest angular resolution in order to detect new binaries. Serendipitous results such as resolved sources and detection of circumstellar components were also anticipated. We have recorded the signal from background stars for a few seconds, around the predicted time of occultation by the Moon's dark limb. At millisecond time resolution, a characteristic diffraction pattern can be observed. Patterns for two or more sources superimpose linearly, and this property is used for the detection of binary stars. The detailed analysis of the diffraction fringes can be used to measure specific properties such as the stellar angular size and the presence of extended light sources such as a circumstellar shell. We present a list of 191 stars for which LO data could be recorded and analyzed. Results include the detection of 16 binary and 2 triple stars, all but one of which were previously unknown. The projected angular separations are as small as 4 milliarcseconds and magnitude differences as high as ?K=5.8 mag...Comment: 10 pages, 3 figures, to be published in A&

    The German version of the Humor Styles Questionnaire: Psychometric properties and overlap with other styles of humor

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    The Humor Styles Questionnaire (HSQ; Martin et al., 2003) is one of the most frequently used questionnaires in humor research and has been adapted to several languages. The HSQ measures four humor styles (affiliative, self-enhancing, aggressive, and self-defeating), which should be adaptive or potentially maladaptive to psychosocial well-being. The present study analyzes the internal consistency, factorial validity, and factorial invariance of the HSQ on the basis of several German-speaking samples combined (total N = 1,101). Separate analyses were conducted for gender (male/female), age groups (16–24, 25–35, &gt;36 years old), and countries (Germany/Switzerland). Internal consistencies were good for the overall sample and the demographic subgroups (.80–.89), with lower values obtained for the aggressive scale (.66–.73). Principal components and confirmatory factor analyses mostly supported the four-factor structure of the HSQ. Weak factorial invariance was found across gender and age groups, while strong factorial invariance was supported across countries. Two subsamples also provided self-ratings on ten styles of humorous conduct (n = 344) and of eight comic styles (n = 285). The four HSQ scales showed small to large correlations to the styles of humorous conduct (-.54 to .65) and small to medium correlations to the comic styles (-.27 to .42). The HSQ shared on average 27.5–35.0% of the variance with the styles of humorous conduct and 13.0–15.0% of the variance with the comic styles. Thus–despite similar labels–these styles of humorous conduct and comic styles differed from the HSQ humor styles.</p

    On the dimensionality of humorous conduct and associations with humor traits and behaviors

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    Abstract The aim of the present study is to explore higher-order dimensions of humorous conduct derived from 100 non-redundant and comprehensive statements. These dimensions are validated in self- and other-reports and their criterion validity is assessed by relating them to other humor concepts (temperamental basis of the sense of humor, attitudes towards laughter and being laughed at, humor appreciation and creation). Four broad dimensions (mean-spirited/earthy, entertaining, inept, and reflective/benign) were supported in self- and other-reports, and two narrower dimensions (laughter and canned) were found in self-reports. These dimensions covered affective, cognitive, and dysfunctional aspects of humorous conduct and spanned across humorous temperament, attitudes towards laughter and being laughed at as well as humor appreciation and creation. These six dimensions can serve as a reference framework and higher-order categories to which humor scales could be assigned. Future studies need to test the comprehensiveness of these dimensions and conduct further validation studies.</jats:p
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