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This paper proposes a new, fully automatic and robust approach to generating triangular meshes directly from volumetric data (scanned images), particularly when these images contain multiple adjacent labels. Current meshing techniques produce a number of mesh elements directly related to the number of components (voxels) in the image. This number can be considerable if the image is large. The proposed methodology is significantly less dense in terms of the number of elements compared to marching cube methods. The proposed method presents no configuration ambiguity and is faithful to the original morphology of the images regardless of the thinness of the topologies or the presence of possible erratic morphological configurations that may lead to geometric interpretation indecisions. [Display omitted] • New fully automatic and robust approach to generate triangular meshes directly from volumetric data, in particular when these images contain adjoining multiple-label. • The proposed methodology is significantly less dense in terms of the number of elements compared to Marching Cube Methods. • The proposed method presents no configuration ambiguity and is faithful to the original morphology of the images regardless of the thinness of the topologies or the presence of possible erratic morphological configurations that may lead to geometric interpretation indecisions. [ABSTRACT FROM AUTHOR]

ABSTRACT Gravity modes present in γ Doradus stars probe the deep stellar interiors and are thus of particular interest in asteroseismology. Mode identification will improve the knowledge of these stars considerably and allow an understanding of the issues with current pulsational models. A frequency analysis followed by a mode identification were done based on the high-resolution spectroscopic data of two γ Doradus stars: HD 189631 and HD 40745. Extensive spectroscopic data sets are obtained by three instruments: HARPS, FEROS and HERCULES. We obtained 422 spectra for HD 189631 and 248 spectra for HD 40745. The pulsational frequencies were determined by four methods: analysis of the variation in equivalent width, variation in radial velocity, asymmetry of the line profile and the pixel-by-pixel frequency analysis. The mode identification was done using the recently developed Fourier Parameter Fit method. Without achieving the same degree of confidence for all results, we report the identification of four pulsational modes in HD 189631: ( ℓ= 1; m =+1) at f1= 1.67 d−1; (3; −2) at f2= 1.42 d−1; (2; −2) at f3= 0.07 d−1; and (4; +1) at f4= 1.82 d−1; and two modes in HD 40745: (2; −1) at f1= 0.75 d−1 and (3; −3) at f2= 1.09 d−1. This study provides the first pulsational analysis based on spectroscopy of HD 189631 and HD 40745. We discuss the performance of current methods of analysis and outline the difficulties presented by γ Doradus stars. [ABSTRACT FROM AUTHOR]

We are undertaking an extensive observational campaign of a number of non-radially pulsating stars using the high-resolution HERCULES spectrograph on the 1.0-m telescope at the Mt John University Observatory. This is part of a large world-wide multi-site campaign to improve mode-identification techniques in non-radially pulsating stars, particularly for g-mode pulsators. This paper outlines our campaign and presents preliminary results for one γ Doradus star, HD 40745, and one β Cephei star, HD 61068. We have used a representative cross-correlation line-profile technique presented by Wright in 2008 to extract line profiles and these have then been analyzed using the FAMIAS package due to Zima published in 2006 to derive a spectroscopic mode identification. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides are used extensively in agriculture and, as a consequence, are now detectable in nearby aquatic environments. Few studies have evaluated the effects of neonicotinoids on amphibians in these aquatic environments. In the present study, we examined the effects of 2 commercial formulations of neonicotinoids (active ingredients clothianidin and thiamethoxam) on survival and life‐history traits of wood frogs (Lithobates sylvaticus) and northern leopard frogs (Lithobates pipiens). We used artificial pond mesocosms to assess the effects of these neonicotinoids, at nominal concentrations of 2.5 and 250 µg/L, on amphibian larval development through metamorphosis. We found no differences between controls and neonicotinoid exposure for any of the endpoints assessed for either wood frogs or leopard frogs. The present study suggests that concentrations meeting or exceeding observed levels of clothianidin and thiamethoxam in surface waters will not directly affect metamorphosis in 2 amphibians. Environ Toxicol Chem 2019;38:1967–1977. © 2019 SETAC. [ABSTRACT FROM AUTHOR]