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The bronze bug Thaumastocoris peregrinus Carpintero & Dellapé (Hemiptera: Thaumastocoridae) was detected infesting Eucalyptus trees in Brazil in 2008, in the states of Sao Paulo, Rio Grande do Sul and Minas Gerais and in 2009 was found in the state of Espírito Santo, Mato Grosso do Sul, Rio de Janeiro and Paraná. Details about geographical spread, means of introduction, impact in Eucalyptus plantations and natural enemies observed in the field are discussed.

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Data for the quenching of the fluorescence of two anthracene-derived amphiphilic fluorescence probes (ethyldimethyl-(I) and trimethyl[3-(9-anthracenyl)propyl]a"onium bromide (II)) in aqueous micellar solutions of the quencher detergents N-hexadecylpyridinium chloride (HPCl), bromide (HPBr), and nitrate (HPNO,) are analyzed in terms of a photophysical model which assumes static quenching of the micelle-incorporated probe and dynamic quenching of the residual fluorescence of the unincorporated probe by free detergent monomer and free counterions. This analysis provides values for the ground-state probe incorporation coefficient K, which are compatible with independent estimates based on the quenching of the emission of the micelle-excluded R~(bpy),~+ ion by I under the same conditions. The results of the present study clearly show that K, for incorporation of a charged amphiphilic substrate into the micellar phase of a like-charged detergent is quite sensitive to the concentration of detergent and added salt present. In addition to this general salt dependence, which can be ascribed to the effects of intermicellar ionic strength and intermicellar interactions on the micellar surface potential, the magnitude of K, also exhibits a significant specific salt (counterion) dependence. Consideration of the consequences of selectivity in counterion exchange at the micelle surface on the effective micellar surface potential provides an analytical expression which rationalizes the observed specific counterion effects on K, for this type of substrate. The implications for the quantitative analysis of ground-state reactions and equilibria in ionic micellar solution are pointed out and methods for estimating K, under diverse experimental conditions suggested.

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The photobehavior of 2,2-diphenyl-3-methyl-2H-azirine (15) and 2-methyl-2,3-diphenyl-2ff-azirine ( 14) was investigated in solution at 298 K. Both azirines undergo ready ring opening on exposure to UV light to give nitrile ylides which can be trapped with methyl acrylate or methanol. In the absence of a trapping reagent, the ylide derived from azirine 15 undergoes 1,5-electrocyclization followed by a 1,3-sigmatropic hydrogen shift to give an isoindole derivative. The transient absorption spectra obtained after pulsed laser photolysis of azirines 14,15, and 2,3-diphenyl-2ff-azirine ( 13) in isooctane at 298 K are in good agreement with those obtained at 77 K in a 3-methylpentane glass. Absolute quenching rate constants for reaction of the ylides derived from azirines 13-15 with acrylonitrile and fumanitrile are consistent with competitive quenching studies. The Arrhenius behavior for the reaction of the ylide derived from azirine 13 with methyl acrylate and diethyl fumarate gives evidence for reversible formation of an ylide-olefin complex.

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