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We examined the feasibility of externally marking insects with the liquid fluorescent forensic theft deterrent, SmartWater (SmartWater CSI, LLC.). We sprayed captive Lygus hesperus (Knight) (Hemiptera: Miridae), Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), and Hippodamia convergens Guérin-Méneville (Coleoptera: Coccinellidae) with SmartWater fluorophore, and then qualitatively examined them for fluorescence by visual inspection under ultraviolet (UV) light and quantitatively measured them with a multiwavelength microplate fluorometer. The results indicate that this product has enormous potential as a taggant for L. hesperus and B. tabaci. However, the marking efficiency for H. convergens was only adequate. The advantages and limitations of using SmartWater as a biological marker for arthropod mark-release-recapture research are discussed.

Vernonia [Vernonia galamensis (Cass.) Less.] (Asterales: Asteraceae) was examined as a potential trap crop for the cotton (Gossypium hirsutum L., Malvales: Malvaceae) arthropod complex. Four rows of vernonia were embedded within a 96-row cotton field. The abundance of true bug pests, true bug predators, and spiders were determined by whole-plant and sweep net sampling procedures during the early, middle, and late phases of the cotton-growing season. The census data showed that the arthropods had a strong preference for the vernonia trap crop throughout the cotton-growing season. The movement of the arthropods from the trap crop into cotton was also measured using the protein immunomarking technique as a mark–capture procedure. The arthropods inhabiting the vernonia trap crop were marked directly in the field with a broadcast spray application of egg albumin (protein) during each phase of the study. In turn, the captured specimens were examined for the presence of the mark by an egg albumin-specific enzyme-linked immunosorbent assay. Very few marked specimens were captured beyond the vernonia trap crop 1, 3, and 6 d after each marking event. The arthropods’ strong attraction and fidelity to vernonia indicate that it could serve as a trap crop for cotton pests and a refuge for natural enemies.

The amplitude and phase modulation observed in a significant fraction of the RR Lyrae variables - the Blazhko effect - represents a long-standing enigma in stellar pulsation theory. No satisfactory explanation for the Blazhko effect has been proposed so far. In this paper we focus on the Stothers (2006) idea, in which modulation is caused by changes in the structure of the outer convective zone, caused by a quasi-periodically changing magnetic field. However, up to this date no quantitative estimates were made to investigate whether such a mechanism can be operational and whether it is capable of reproducing the light variation we observe in Blazhko variables. We address the latter problem. We use a simplified model, in which the variation of turbulent convection is introduced into the non-linear hydrodynamic models in an ad hoc way, neglecting interaction with the magnetic field. We study the light curve variation through the modulation cycle and properties of the resulting frequency spectra. Our results are compared with Kepler observations of RR Lyr. We find that reproducing the light curve variation, as is observed in RR Lyr, requires a huge modulation of the mixing length, of the order of +/-50 per cent, on a relatively short time-scale of less than 40 days. Even then, we are not able to reproduce neither all the observed relations between modulation components present in the frequency spectrum, nor the relations between Fourier parameters describing the shape of the instantaneous light curves.

We present Kepler satellite photometry of KIC 10661783, a short-period binary star system which shows total eclipses and multi-periodic delta Scuti pulsations. A frequency analysis of the eclipse-subtracted light curve reveals at least 68 frequencies of which 55 or more can be attributed to pulsation modes. The main limitation on this analysis is the frequency resolution within the 27-day short-cadence light curve. Most of the variability signal lies in the frequency range 18 to 31 c/d, with amplitudes between 0.1 and 4 mmag. One harmonic term (2.f) and a few combination frequencies (f_i+f_j) have been detected. From a plot of the residuals versus orbital phase we assign the pulsations to the primary star in the system. The pulsations were removed from the short-cadence data and the light curve was modelled using the Wilson-Devinney code. We are unable to get a perfect fit due to the residual effects of pulsations and also to the treatment of reflection and reprocessing in the light curve model. A model where the secondary star fills its Roche lobe is favoured, which means that KIC 10661783 can be classified as an oEA system. Further photometric and spectroscopic observations will allow the masses and radii of the two stars to be measured to high precision and hundreds of delta Scuti pulsation frequencies to be resolved. This could lead to unique constraints on theoretical models of delta Scuti stars, if the evolutionary history of KIC 10661783 can be accounted for.