2,738 research outputs found

    Evaluation of Faraday-shielded Stix coils for ion cyclotron resonance heating of a plasma Technical report no. 3

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    Faraday-shielded Stix coil evaluation including electric field waveform for ion cyclotron resonance heating of plasm

    Agronomic and economic evaluation of weed management methods in organic herb and vegetable production systems

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    Weed management is reported to be a major constraint in organic agriculture. Organic growers also report a lack of information about non-chemical weed control. A series of field trials was conducted in lettuce (Lactuca sativa L.) and echinacea (Echinacea purpurea (L.) Moench) crops to evaluate a range of weed control methods commonly used in organic herb and vegetable production systems. The criteria for evaluating the methods were weed growth, crop yield and cost effectiveness. Hand weeding, tillage and organic mulches (hay and pelletised paper) were effective to very effective at suppressing weeds. In general, good weed suppression was correlated with good crop yields; however, crop yields were reduced by tillage and paper mulch. Deducting the cost of the weed control method from the gross crop value caused a greater re-ranking of the treatment performance in lettuce than in echinacea. This is partly due to the different growing season lengths and market prices of the two test crops. The most cost effective methods for managing weeds in lettuce were tillage and hand weeding. When weed competition is low, the unweeded control treatment was also cost effective. In echinacea, hand weeding and hay mulch were consistently the most cost effective methods for managing weeds

    EPIC 219217635: A Doubly Eclipsing Quadruple System Containing an Evolved Binary

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    We have discovered a doubly eclipsing, bound, quadruple star system in the field of K2 Campaign 7. EPIC 219217635 is a stellar image with Kp=12.7Kp = 12.7 that contains an eclipsing binary (`EB') with PA=3.59470P_A = 3.59470 d and a second EB with PB=0.61825P_B = 0.61825 d. We have obtained followup radial-velocity (`RV') spectroscopy observations, adaptive optics imaging, as well as ground-based photometric observations. From our analysis of all the observations, we derive good estimates for a number of the system parameters. We conclude that (1) both binaries are bound in a quadruple star system; (2) a linear trend to the RV curve of binary A is found over a 2-year interval, corresponding to an acceleration, γ˙=0.0024±0.0007\dot \gamma = 0.0024 \pm 0.0007 cm s−2^{-2}; (3) small irregular variations are seen in the eclipse-timing variations (`ETVs') detected over the same interval; (4) the orbital separation of the quadruple system is probably in the range of 8-25 AU; and (5) the orbital planes of the two binaries must be inclined with respect to each other by at least 25∘^\circ. In addition, we find that binary B is evolved, and the cooler and currently less massive star has transferred much of its envelope to the currently more massive star. We have also demonstrated that the system is sufficiently bright that the eclipses can be followed using small ground-based telescopes, and that this system may be profitably studied over the next decade when the outer orbit of the quadruple is expected to manifest itself in the ETV and/or RV curves.Comment: Accepted for publication in MNRA

    Next Generation Network Real-Time Kinematic Interpolation Segment to Improve the User Accuracy

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    This paper demonstrates that automatic selection of the right interpolation/smoothing method in a GNSS-based network realtime kinematic (NRTK) interpolation segment can improve the accuracy of the rover position estimates and also the processing time in the NRTK processing center. The methods discussed and investigated are inverse distance weighting (IDW); bilinear and bicubic spline interpolation; kriging interpolation; thin-plate splines; and numerical approximation methods for spatial processes. The methods are implemented and tested using GNSS data from reference stations in the Norwegian network RTK service called CPOS.Data sets with an average baseline between reference stations of 60–70 kmwere selected. 12 prediction locations were used to analyze the performance of the interpolation methods by computing and comparing different measures of the goodness of fit such as the root mean square error (RMSE), mean square error, and mean absolute error, and also the computation time was compared. Results of the tests show that ordinary kriging with theMat´ern covariance function clearly provides the best results. The thin-plate spline provides the second best results of the methods selected and with the test data used

    Multivariate analysis of oestrogen receptor alpha, pS2, metallothionein and CD24 expression in invasive breast cancers

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    Determination of oestrogen receptor alpha (ER) represents at present the most important predictive factor in breast cancers. Data of ours and of other authors suggest that promising predictive/prognostic factors may also include pS2, metallothionein (MT) and CD24. Present study aimed at determining prognostic and predictive value of immunohistochemical determination of ER, pS2, MT, and CD24 expression in sections originating from 104 patients with breast cancer. An univariate and multivariate analysis was performed. Both univariate and multivariate analyses demonstrated that cytoplasmic-membranous expression of CD24 (CD24c-m) represents a strong unfavourable prognostic factor in the entire group and in most of the subgroups of patients. In several subgroups of the patients also a prognostic value was demonstrated of elevated expression of pS2 and of membranous expression of CD24. Our studies demonstrated that all patients with good prognostic factors (higher ER and pS2 expressions, lower MT expression, CD24c-m negativity) survived total period of observation (103 months). The study documented that cytoplasmic-membranous expression of CD24 represented an extremely strong unfavourable prognostic factor in breast cancer. Examination of the entire panel of the studied proteins permitted to select a group of patients of an exceptionally good prognosis

    Determination of the Her-2/neu gene amplification status in cytologic breast cancer specimens using automated silver-enhanced in-situ hybridization (SISH)

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    Silver-enhanced in-situ hybridization (SISH) is an emerging tool for the determination of the Her-2/neu amplification status in breast cancer. SISH is technically comparable to fluorescence in-situ hybridization (FISH) but does not require a fluorescence microscope for its interpretation. Although recent studies on histologic evaluations of SISH are promising, we aimed to evaluate its performance on 71 cytologic breast cancer specimens with the new combined Her-2/Chr17 probe. Her-2/neu status as routinely determined by FISH was available for all patients. We found SISH signals in cytologic cell blocks and smear specimens easy to evaluate in most cases. Small numbers of tumor cells and difficulties in identifying tumor cells in lymphocyte-rich backgrounds were limiting factors. Her-2/neu status, as determined by Her-2/Chr17 SISH, was basically identical to the results of the corresponding FISH. The discrepancies were mainly owing to the heterogeneity of Her-2/neu amplification in the tumor tissue. Interobserver agreement for the SISH evaluation was high (kappa value: 0.972). We conclude that Her-2/Chr17 SISH is a useful and accurate method for the evaluation of the Her-2/neu gene amplification status in cytologic breast cancer specimens, particularly in metastatic breast cancer lesions. The advantages of signal permanency and bright-field microscopic result interpretation make this technique an attractive alternative to the current FISH-based gold standard

    The Certification of the Mass Concentrations of Aluminium, Selenium and Zinc in Human Serum, BCR-637, BCR-638, BCR-639.

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    Abstract not availableJRC.D-Institute for Reference Materials and Measurements (Geel

    Cosmological implications of the KATRIN experiment

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    The upcoming Karlsruhe Tritium Neutrino (KATRIN) experiment will put unprecedented constraints on the absolute mass of the electron neutrino, \mnue. In this paper we investigate how this information on \mnue will affect our constraints on cosmological parameters. We consider two scenarios; one where \mnue=0 (i.e., no detection by KATRIN), and one where \mnue=0.3eV. We find that the constraints on \mnue from KATRIN will affect estimates of some important cosmological parameters significantly. For example, the significance of ns<1n_s<1 and the inferred value of ΩΛ\Omega_\Lambda depend on the results from the KATRIN experiment.Comment: 13 page
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