Abundance and Flight Activity of Some Histeridae, Hydrophilidae and Scarabaeidae (Coleoptera) in Southern Quebec, Canada

We collected adult beetles with four unbaited flight intercept traps in southern Quebec, from early May through late October, in 1987, 1988 and 1989. We captured a total of 146 Histeridae (9 species), 668 Hydrophilidae (29 species) and 428 Scarabaeidae (25 species), including 25 Holarctic or introduced species in North America, mainly non-forest hydrophilids and scarabs.The Sphaeridiinae and Aphodiinae represented, respectively, 78% of hydrophilid catches and 86% of scarab captures. We suggest that adults of Aphodius prodromus, the most common scarab species, are generalist detritivores. Overwintered adults of this species, mainly females, flew in spring, and new generation adults occurred mainly in October. We also studied the seasonal flight activity of three histerid species (Aeletes politus, Geomysaprinus obsidianus, Margarinotus lecontei), ten hydrophilid species (Anacaena prob. lutescens, Cercyon analis, C. assecla, C. haemorrhoidalis, C. lateralis, C. minusculum, C. pygmaeus, Cryptopleurum minutum, Helophorus orientalis, Hydrobius fuscipes) and three other scarab species (Aphodius granarius, A. rufipes, Dichelonyx albicollis). All these species are probably univoltine in southern Quebec

Abundance and Seasonal Activity of Weevils (Coleoptera: Curculionidae) in a Raspberry Plantation and Adjacent Sites in Southern Quebec (Canada).

In a raspberry plantation and adjacent sites in southern Quebec, we collected weevils with unbaited pitfall traps and flight interception traps from early May througb late October in 1987-1989. We captured a total of 1592 weevils representing 65 species, including at least 21 Holarctic or introduced species in North America. In and around the raspberry plantation, the commonest species collected by the two methods were the short-nosed weevils of subfamilies Otiorhynchinae and Thylacitinae, mainly generalist species with root-feeding larvae. Ceutorhynchinae and Tychiinae species were also abundant in flight traps near the raspberry plantation, whereas Hylobius congener was the most abundant weevil active at the ground surface in an adjacent pine woods. Sciaphilus asperatus and Otiorhynchus ovatus, two introduced wing­ less weevils, were the most abundant species caught with pitfall traps in raspberry rows; the increase of their abundance in the young plantation was probably associated with the increase of raspberry root mass and canopy during the three study years. The weevil fauna at a woods-field boundary was quite variable in the relative abundance of species active in open sites or in wooded sites. We studied the seasonal activity of H. congener, O. ovatus, S. asperatus, Sitona lepidus, Trachyphloeus bifoveolatus, and nine other minor weevil species

Epigeal and Flight Activity of Coleoptera in a Commercial Raspberry Plantation and Adjacent Sites in Southern Quebec (Canada): Introduction and Nitidulidae

We studied the epigeal and flight activity of Coleoptera in a commercial raspberry plantation and adjacent sites in southern Quebec, from 1987-1989. In this first paper, we present the results for the Nitidulidae. Pitfall traps yielded 521 beetles representing 15 species; Glischrochilus quadrisignatus represented 86% of catches in raspberry rows (old and young plants), and Epuraea spp. were the most abundant nitidulids in a woods-field boundary and in a pine woods. Nitidulids in flight interception traps comprised 2179 individuals of 28 species; Meligethes nigrescens was the most abundant species in open sites around the raspberry plantation, while Epuraea avara and E. ovata were common in the boundary and pine woods. Species composition in the boundary was quite variable in the relative abundance of species flying either in open sites or in wooded sites. We studied the seasonal activity of Colopterus truncatus, E. avara, E. ovata, G. fasciatus, G. quadrisignatus, M nigrescens, and some other minor species. We suspect that during their mating period, overwintered adults of M nigrescens could playa role in raspberry pollinization

Faunal Composition, Wing Polymorphism and Seasonal Abundance of Some Flea Beetles (Coleoptera: Chrysomelidae) in Southern Quebec (Canada)

Chrysomelidae (51 taxa) were collected with flight intercept traps from May through October during 1987-1989, in four sites near a raspberry plantation in southern Quebec. More species and individuals of phytophagous flea beetles occurred in two open sites than at a pine woods-raspberry field boundary and in a pine woods. Longitarsus luridus complex, an immigrant taxon in North America, represented 58% of all captures in the two open sites where both Ranunculus acris and Plantago spp. are its main host plants; this species and Longitarsus rubiginosus were almost exclusively represented by jumping apterous adults in pans of flight intercept traps. The seven most abundant chrysomelid species from Johnville are probably all univoltine, and they are apparently not serious raspberry pests. Three life cycle types are apparent: L. luridus complex oviposit in autumn and overwinter as adults. Capraita subvittata, Chaetocnema minuta, Epitrix cucumeris, Phyllotreta striolata and Tricholochmaea alni also overwinter as adults but oviposition begins in spring. Longitarsus rubiginosus oviposits in autumn, overwintering in the egg and/or larval stage

Anomalous Surface Segregation Profiles in Ferritic FeCr Stainless Steel

The iron-chromium alloy and its derivatives are widely used for their remarkable resistance to corrosion, which only occurs in a narrow concentration range around 9 to 13 atomic percent chromium. Although known to be due to chromium enrichment of a few atoms thick layer at the surfaces, the understanding of its complex atomistic origin has been a remaining challenge. We report an investigation of the thermodynamics of such surfaces at the atomic scale by means of Monte Carlo simulations. We use a Hamiltonian which provides a parameterization of previous ab initio results and successfully describes the alloy's unusual thermodynamics. We report a strong enrichment in Cr of the surfaces for low bulk concentrations, with a narrow optimum around 12 atomic percent chromium, beyond which the surface composition decreases drastically. This behavior is explained by a synergy between (i) the complex phase separation in the bulk alloy, (ii) local phase transitions that tune the layers closest to the surface to an iron-rich state and inhibit the bulk phase separation in this region, and (iii) its compensation by a strong and non-linear enrichment in Cr of the next few layers. Implications with respect to the design of prospective nanomaterials are briefly discussed.Comment: 6 pages, 4 figure

Exploring the host environments of long-duration gamma-ray bursts

We have conducted the first dedicated spectroscopic survey of long-duration gamma-ray burst (LGRB) host galaxies at z < 1, and use these observations along with data from the literature to determine a wide range of ISM properties and a statistically robust mass-metallicity relation. LGRBs have been proposed as possible tracers of star formation at high redshift; however, such an association is dependent on a thorough understanding of the relationship between LGRB progenitors and their host environments. In particular, the metallicity of LGRB host galaxies has become a matter of hot debate in recent years. We conclude that LGRBs do exhibit a general trend toward lower-metallicity host galaxies, but also detect several high-metallicity hosts in our sample. We have also compared the energetic and environmental properties of the LGRBs in our sample, and find no statistically significant correlation between host metallicity and isotropic or beaming-corrected gamma-ray energy release. This is at odds with previous theoretical and observational predictions of an inverse correlation between gamma-ray energy release and host metallicity, and demonstrates that the complex role of metallicity in LGRB progenitor formation still remains unclear.Comment: 4 pages, 2 figures; to appear in AIP proceedings of "Gamma Ray Bursts 2010

The Host Galaxies of Long-Duration Gamma-Ray Bursts

Long-duration gamma-ray bursts (LGRBs) are the signatures of extraordinarily high-energy events occurring in our universe. Since their discovery, we have determined that these events are produced during the core-collapse deaths of rare young massive stars. The host galaxies of LGRBs are an excellent means of probing the environments and populations that produce their unusual progenitors. In addition, these same young stellar progenitors makes LGRBs and their host galaxies valuable potentially powerful tracers of star formation and metallicity at high redshifts. However, properly utilizing LGRBs as probes of the early universe requires a thorough understanding of their formation and the host environments that they sample. This review looks back at some of the recent work on LGRB host galaxies that has advanced our understanding of these events and their cosmological applications, and considers the many new questions that we are poised to pursue in the coming years.Comment: 33 pages, 4 figures, 1 table; invited review for PASP, in pres