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Aims. We report the discovery of very shallow ($\Delta F/F \approx 3.4\times 10^{-4}$), periodic dips in the light curve of an active $V = 11.7$G9V star observed by the CoRoT  satellite, which we interpret as caused by a transiting companion. We describe the 3-colour CoRoT data and complementary ground-based observations that support the planetary nature of the companion.

Context. CoRoT is a space telescope dedicated to stellar seismology and the search for extrasolar planets. The mission is led by the CNES in association with French laboratories and has a large international participation. The European Space Agency (ESA), Austria, Belgium, and Germany contribute to the payload, and Spain and Brazil contribute to the ground segment. Development of the spacecraft, which is based on a PROTEUS low earth orbit (LEO) recurrent platform, commenced in October 2000, and the satellite was launched on December 27, 2006.

AbstractThe growth (increase in body mass) and development (progression to specific instar) of the bertha armyworm, Mamestra configurataWalker, were examined using up to 14 plant lines from five species of brassicaceous plants. Varietal and breeding lines of Brassica napusL., B. junceaL., B. rapaL., B. carinataL., and Sinapis albaL. were selected on the basis of differing seed and foliar glucosinolate levels. No-choice feeding experiments were conducted with larvae isolated on leaf discs, individual leaves, or entire plants of each line. The no-choice tests showed that M. configurataweight gain and development varied significantly among host plants tested. Two B. juncealines (AC Vulcan and H-Allyl) and the S. albalines (AC Pennant and L-GS) were the poorest hosts in terms of larval weight gain, and the two B. juncealines also significantly slowed development relative to the other lines tested. Mamestra configuratafeeding preference, which was examined using a series of paired leaf disc choice tests, was also significantly different among the lines examined. Two B. juncealines (AC Vulcan and H-Allyl) were significantly less preferred than all the other lines examined. The data extends previous work indicating that specific foliar glucosinolates, such as sinigrin, which is predominant in B. juncea, and sinalbin, which is abundant in S. alba, may provide brassicaceous crops with some protection from M. configurata. Thus, it may be possible to use foliar glucosinolate levels as predictors of M. configuratafeeding damage in the development of breeding lines for the genus Brassica.

A novel silicon-based linkage and cleavage strategy for solid-phase synthesis of aromatic organic compounds has been developed. The method is based on the following steps:  (i) attachment of silanes of the formula type R¹R²(R³O)Si(CH2)nNCH2CH2N(R⁴)CH2CH2 (R¹ = aryl; R² = aryl, alkyl; R³, R⁴ = alkyl; n = 1, 3) to a Merrifield resin via R⁴, (ii) reactions with the resin-linked silanes (chemical transformations of the aryl group R¹; R¹ → → → R^1*), and (iii) treatment of the R^1*R²(R³O)Si(CH2)nNCH2CH2N(R⁴)CH2CH2-containing resin with 1,2-dihydroxybenzene in acetonitrile at 50 °C to give the cleavage products R^1*H (release of the target molecules in a traceless fashion), R²H, and R³OH, along with the resin-linked zwitterionic pentacoordinate silicate of the formula type (1,2-C6H4O2)2Si(CH2)nN(H)CH2CH2N(R⁴)CH2CH2.

A traffic sign detection and recognition approach is presented in this paper. This project is a part of the European research project PROMETHEUS(PROgraM for a European Traffic with Highest Efficiency and Unprecedented Safety) and is being developed by DAIMLER BENZ in collaboration with various university labs. Intensity segmentation, shape and traffic sign recognition have been joined together in a processing chain. Uncertainty handling, combining and propagation using Dernpster-Shafer rules fonn the heart of the shape recognition method. Multiple Knowledge Sources extract infonnation from the segmented image and increase knowledge about undefined shapes. Recognized shapes are transmitted to a high-level processing stage which perfonns model-based traffic sign recognition.

Summary 2,3-diphosphoglycerate, favoring the deoxyconfiguration of the hemoglobin molecule, accelerates the oxidation of hemoglobin to methemoglobin by potassiumferricyanide both in hemolysates from adult and cord blood. Hemoglobin oxidation is less enhanced in cord blood hemolysates.

Field and laboratory studies investigated the preimaginal developmental time, adult emergence phenology, mating behavior, and weevil hosts of Necremnus tidius (Walker) (Hymenoptera: Eulophidae), a solitary ectoparasitoid of coleopteran larvae. In addition, changes in parasitism levels of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae), by N. tidius were determined during 2003-2005 in commercial fields of canola (Brassica rapa L. and Brassica napus L.) in southern Alberta and Saskatchewan, Canada. Mean ± SE developmental time from egg to adult was 18.3 ± 0.23 d for specimens reared at 21°C and a photoperiod of 12:12 (L:D) h. Emergence began in late July in commercial fields near Lethbridge, AB, and 20 d later 81% of the population had emerged. Emergence was completed by the end of August. Mating was preceded by a complex courtship behavior with the male standing on the dorsum of the mesosoma and gaster of the female, flapping its wings without flight, leaning forward and stroking its antennae over the antennae of the female, leaning back, and repeating the sequence several times. The native weevil Ceutorhynchus neglectus Blatchley was determined to be an alternate host of N. tidius in central and northern Alberta. N. tidius was found in few commercial canola fields in 2003, but in 2004, it occurred over hundreds of thousands of hectares of canola cropland, reaching peak parasitism levels of 45%. In 2005, N. tidius was still common, but parasitism declined relative to that observed in 2004.

Since the description of Ceutorhynchus subpubescens LeConte (Coleoptera: Curculionidae) >125 yr ago, very little information has been published on its biology, taxonomy, or distribution. We conducted studies in southern Alberta, Canada, to investigate aspects of its life history and host plant feeding preferences. Preimaginal life stages of C. subpubescens were described for the first time, and data were compiled on its North American distribution. Ceutorhynchus subpubescens was univoltine. Adults emerged from overwintering sites in shelterbelts in late April to early May, and first occurred on host plants in May. Eggs were laid into apical stem regions of flixweed, Descurainia sophia (L.) Webb (Brassicaceae), and hatched to larvae that mined the stems, feeding primarily on pith tissue. Three instars developed within D. sophia. When mature, the final instar bored an exit hole in the primary stem, just below the juncture of a lateral shoot. Developmental time from eggs to final instars required only 35–45 d, an adaptation that accommodated the rapid development of D. sophia hosts. Setal numbers on the mouthparts and head capsule distinguished final instars of C. subpubescens from its sympatric congeners, Ceutorhynchus neglectus Blatchley and Ceutorhynchus obstrictus (Marsham). New distribution records for the species include Alberta, Arizona, Montana, Nebraska, New Mexico, Oregon, Saskatchewan, South Dakota, and Washington. C. subpubescens has adapted to exploit a resource-rich habitat, where larvae are free from interference from predators and parasitoids; however, its relatively rare occurrence in western North America is surprising given the abundance of its host plants.

The spring emergence biology of Ceutorhynchus obstrictus (Marsham) was investigated in 2003 and 2004 in relation to habitat type, vegetative cover, and soil temperature in the Mixed Grassland Ecoregion of western Canada. Although total emergence extended over 10–12 wk, emergence patterns were very similar in both years with limited emergence occurring for several weeks before and after a large emergence peak of comparatively short duration. In 2003, peak emergence occurred during a 3-wk period from 28 May to 13 June when 97.6% of C. obstrictus were collected; and in 2004, emergence of 55.6% of weevils occurred during the 1-wk period before 4 June. Peak emergence occurred as mean ground temperature (5 cm in depth) reached 15°C. The greatest number of weevils recorded from a single 1-m2 emergence trap was 956. Significantly more weevils emerged from sheltered and intermediately sheltered locations than from open grassy habitats; sheltered areas were predominantly shelterbelts and yard sites of caragana and poplar trees. No weevils emerged from 14 of 106 cages, and all cages were in open grassy habitat. Spring emergence of weevils in open grassy areas occurred slightly before those in sheltered and intermediately sheltered areas. Cages in open grassy habitat had the highest mean temperature as well as the highest maximum and lowest minimum temperatures in each sampling period. Significantly more males than females emerged early in the season, although during peak emergence there was no difference in sex ratio; and after peak emergence, significantly more females than males emerged.

Survival, development, and oviposition of the polyphagous insect Mamestra configurata Walker (Lepidoptera: Noctuidae) were compared on different host plant species of the families Brassicaceae [Brassica rapa L., Brassica napus L., Brassica juncea (L.) Cosson, Sinapis alba L., and Thlaspi arvense L.], Compositae [Cirsium arvense (L.) Scop.], Leguminosae (Pisum sativum L. and Medicago sativa L.), Linaceae (Linum usitatissimum L.), and Chenopodiaceae (Chenopodium album L.). Larvae developed faster on intact host plant tissue of all species than they did on excised leaf tissue. First instars of M. configurata did not survive on leaves of T. arvense. Although 97% of larvae survived to the sixth instar on M. sativa, complete mortality was observed on this host plant before pupation. On the other host plants studied, survival rates to sixth instar and pupation were similar. C. album was significantly more preferred than all other species in larval feeding choice experiments, whereas B. juncea and M. sativa were significantly less preferred than the other species. Pupal weights were highest on C. album and S. alba and were lowest on P. sativum and B. juncea. Larval development was most rapid on C. album and was slowest on B. juncea. C. album was significantly more preferred for oviposition than B. napus, B. rapa, C. arvense, and B. juncea. The ovipositional and feeding preferences for C. album suggest that species of Chenopodiaceae were important hosts of M. configurata before vast monocultures of B. napus and B. rapa were introduced to western North America.