369 research outputs found

    Report on the Alternative Platform Observer Program in North Carolina: March 2006 to March 2007

    Get PDF
    In February 2006, an Alternative Platform Observer Program (APP) was implemented in North Carolina (NC) to observe commercial gillnet trips by small vessels [<24 ft (7.2 m)] in nearshore waters out to three nm (5.6 km). Efforts began with outreach to the fishing industry while simultaneously gathering information to be incorporated in a Database of Fishermen. From 30 March 2006 through 31 March 2007, 36 trips were observed. Observed trips of the NC nearshore gillnet fishery targeted seven species: kingfish (Menticirrhus spp.), Spanish mackerel (Scomberomorus maculatus), spiny dogfish (Squalus acanthias), spot (Leiostomus xanthurus), spotted seatrout (Cynoscion nebulosus), striped bass (Morone saxatilis), and weakfish (Cynoscion regalis). Of the 36 trips, 20 (55.6%) were with vessels that were new to the Northeast Fisheries Observer Program (NEFOP), having never carried an observer. Based on the landings data for small vessels from North Carolina Division of Marine Fisheries (NCDMF), the APP has achieved 10.1% coverage by number of trips and 4.0% by pounds landed. No incidental takes of bottlenose dolphins were observed by the APP, although bottlenose dolphins were sighted during 19 (52.8%) observed trips. The APP has drastically increased the number of observed trips of small vessels in the nearshore waters of NC. When combined with trips observed by NEFOP (n=205), the APP resulted in a 15.6% increase in the number of observed gillnet trips. (PDF contains 34 pages

    Improved Acid Stress Survival of Lactococcus lactis Expressing the Histidine Decarboxylation Pathway of Streptococcus thermophilus CHCC1524

    Get PDF
    Background: Degradative amino acid decarboxylation pathways in bacteria have diverse physiological functions. Results: A histidine decarboxylation pathway introduced in L. lactis improves acid stress survival, and synergy with the glycolytic pathway is demonstrated. Conclusion: The physiological benefit of the new pathway is strongly dependent on the properties of the host organism. Significance: Acquisition of the histidine decarboxylation pathway mimics successful horizontal gene transfer

    Morphological asymmetry and interspecific hybridization: A case study using hylid frogs

    Get PDF
    The limited studies addressing developmental stability of interspecific hybrids suggest a positive association between the level of fluctuating asymmetry and 1) the degree of divergence between parental species, and 2) the recency of the contact zone. To evaluate these associations, we examined asymmetry in a recentlyestablished hybrid population of treefrogs (Hyla cinerea and H. gratiosa) that show marked structural gene divergence. Fluctuating asymmetry (FA), directional asymmetry, and antisymmetry were assessed for eight paired osteometric traits in allozymically-defined parental and hybrid categories. FA levels varied considerably among traits. Nonetheless, for any given trait, the hybrid categories did not demonstrate elevated levels of FA compared to the parental categories, or compared to frogs from a non-hybridizing parental population. The only trait that differed statistically among categories (pterygoid length) involved a significantly lower FA value for the Fl hybrids. Thus, observed FA values do not support expectations that the hybrid categories should experience decreased developmental stability

    Morphological asymmetry and interspecific hybridization: A case study using hylid frogs

    Get PDF
    The limited studies addressing developmental stability of interspecific hybrids suggest a positive association between the level of fluctuating asymmetry and 1) the degree of divergence between parental species, and 2) the recency of the contact zone. To evaluate these associations, we examined asymmetry in a recentlyestablished hybrid population of treefrogs (Hyla cinerea and H. gratiosa) that show marked structural gene divergence. Fluctuating asymmetry (FA), directional asymmetry, and antisymmetry were assessed for eight paired osteometric traits in allozymically-defined parental and hybrid categories. FA levels varied considerably among traits. Nonetheless, for any given trait, the hybrid categories did not demonstrate elevated levels of FA compared to the parental categories, or compared to frogs from a non-hybridizing parental population. The only trait that differed statistically among categories (pterygoid length) involved a significantly lower FA value for the Fl hybrids. Thus, observed FA values do not support expectations that the hybrid categories should experience decreased developmental stability

    Differences in demographic traits of four butterflyfish species between two reefs of the Great Barrier Reef separated by 1,200 km

    Get PDF
    Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Coral Reefs 31 (2012): 169-177, doi:10.1007/s00338-011-0838-z.Many species demonstrate variation in life history attributes in response to gradients in environmental conditions. For fishes, major drivers of life history variation are changes in temperature and food availability. This study examined large-scale variation in the demography of four species of butterflyfishes (Chaetodon citrinellus, C. lunulatus, C. melannotus, and C. trifascialis) between two locations on Australia’s Great Barrier Reef (Lizard Island and One Tree Island, separated by approximately 1200km). Variation in age-based demographic parameters was assessed using the re-parameterised von Bertalanffy growth function. All species displayed measurable differences in body size between locations, with individuals achieving a larger adult size at the higher latitude site (One Tree Island) for three of the four species examined. Resources and abundances of the study species were also measured, revealing some significant differences between locations. For example, for C. trifascialis, there was no difference in its preferred resource or in abundance between locations, yet it achieved a larger body size at the higher latitude location, suggesting a response to temperature. For some species, resources and abundances did vary between locations, limiting the ability to distinguish between a demographic response to temperature as opposed to a response to food or competition. Future studies of life histories and demographics at large spatial scales will need to consider the potentially confounding roles of temperature, resource usage and availability, and abundance / competition in order to disentangle the effects of these environmental variables.This work was supported by a National Science Foundation (USA) Graduate Research Fellowship (MLB) and by PADI Project A.W.A.R.E. (MLB).2012-11-1

    Balanceren tussen wonen en werken:Een onderzoek naar mobiliteitsreduktie in de vervoerregio Groningen via aanpassingen van de woon-werkbalans

    Get PDF
    Centraal thema in dit onderzoek is de vraag of door een andere spreiding van werkgelegenheid of woonfuncties een wezenlijke bijdrage kan worden geleverd aan de doelstelling van de (auto)mobiliteitsreductie. Aan de hand van enquĂȘtes onder werknemers van bedrijven is nagegaan welke (ruimtelijke) maatregelen de meeste invloed kunnen hebben op het woon-werkverkeer in de Vervoerregio Groningen. Daarnaast is nog een afzonderlijke enquĂȘte uitgezet om bedrijfsspecifieke gegevens te verzamelen

    Evidence of Two Functionally Distinct Ornithine Decarboxylation Systems in Lactic Acid Bacteria

    Get PDF
    Biogenic amines are low-molecular-weight organic bases whose presence in food can result in health problems. The biosynthesis of biogenic amines in fermented foods mostly proceeds through amino acid decarboxylation carried out by lactic acid bacteria (LAB), but not all systems leading to biogenic amine production by LAB have been thoroughly characterized. Here, putative ornithine decarboxylation pathways consisting of a putative ornithine decarboxylase and an amino acid transporter were identified in LAB by strain collection screening and database searches. The decarboxylases were produced in heterologous hosts and purified and characterized in vitro, whereas transporters were heterologously expressed in Lactococcus lactis and functionally characterized in vivo. Amino acid decarboxylation by whole cells of the original hosts was determined as well. We concluded that two distinct types of ornithine decarboxylation systems exist in LAB. One is composed of an ornithine decarboxylase coupled to an ornithine/putrescine transmembrane exchanger. Their combined activities results in the extracellular release of putrescine. This typical amino acid decarboxylation system is present in only a few LAB strains and may contribute to metabolic energy production and/or pH homeostasis. The second system is widespread among LAB. It is composed of a decarboxylase active on ornithine and L-2,4-diaminobutyric acid (DABA) and a transporter that mediates unidirectional transport of ornithine into the cytoplasm. Diamines that result from this second system are retained within the cytosol.
    • 

    corecore