1,598 research outputs found

    The foraging ecology of greyheaded mollymawks at Marion Island: in relation to known longline fishing activity

    Get PDF
    Incidental mortality due to longline fishing has been implicated as the main cause for the global population decline in grey-headed mollymawks (Thalassarche chrysostoma). Two of these fisheries, within the potential foraging range of grey-headed mollymawks breeding on Marion Island, have increased drastically over the past 5–10 years. In order to understand the impacts of these fisheries on the grey-headed mollymawk population breeding on Marion Island, we studied their foraging ecology by tracking their foraging trips and sampling their diets. During the incubation stage, birds made long foraging trips, mostly towards the subtropical convergence and sub-Antarctic zones, bringing them into contact with areas of intense southern blue-fin tuna (Thunnus maccoyii) longline fishing. Females spent a higher proportion of their time within these areas than males, thus exposing themselves to a higher risk of incidental mortality from this fishery. During the early chick-rearing stage, foraging trips were shorter and to the southwest of the island in the Polar frontal and Antarctic zones, thus avoiding any contact with the southern blue-fin tuna industry. However, short foraging trips (<2 days) were made within the boundary of known Patagonian toothfish (Dissostichus eleginoides) longline sets around Marion Island. Males made a higher proportion of short foraging trips and spent more time within the boundaries of the toothfish fishery than females. These differences may account for the male-biased mortality of grey-headed mollymawks observed in the toothfish fishery around Marion Island. Although a decrease in the annual breeding population has not been detected on Marion Island as yet, we warn that the methods used to detect these changes are inaccurate in measuring short term population changes (<10 years) and that the impacts of these fisheries may already have altered the demographic structure of this population

    A pilot study on bacterial isolates associated with purulent vaginal discharge in dairy cows in the south‐west region of Western Australia

    Get PDF
    This study aimed to determine the bacterial isolates associated with postpartum endometritis among dairy cows in Western Australia and their antimicrobial susceptibility profiles. A cross-sectional study was conducted between June–October 2020. Endometritis was defined as evidence of mucopurulent to purulent vaginal discharge 60–100 days postpartum. Vaginal discharge samples were obtained, cultured, identified and tested for antimicrobial susceptibility. A total of 118 bacterial isolates were grown from 46 animals, representing 36 species. The bacteria isolated from both aerobic and anaerobic cultures included Bacillus (60.2%), Streptococcus (12.7%), Trueperella (10.1%), Escherichia (6.7%) and Staphylococcus (5.9%). The remaining genera <5% were Histophilus, Aeroccocus, Enterococcus and Moraxella. Resistance was variable between isolates, but the highest resistance levels were observed in Streptococcal and Bacillus isolates to enrofloxacin, clindamycin and erythromycin, respectively. All Streptococcal isolates exhibited 100% resistance to enrofloxacin, and the greatest resistance levels were found in Streptococcus luteinises to trimethoprim-sulfamethoxazole 83%, clindamycin 66% and 33% quinupristin-dalfopristin. There was 84.5% resistance to clindamycin and 35.2% to erythromycin in the Bacillus isolates, with the highest resistance found in Bacillus licheniformis and Bacillus subtilis. Escherichia coli exhibited 12.5% resistance to gentamycin, ceftiofur, whereas amoxicillin-clavulanic acid exhibited 37.5%. Within the Staphylococcal isolates, 28.5%, 28.5%, 42.8% and 14.2% resistance to ceftiofur, erythromycin, cefoxitin, penicillin and tetracycline were observed, respectively. The presence of resistance to important antimicrobials for human use, such as cephalosporins, macrolides and fluoroquinolones, highlights the need for judicious use of antimicrobials in dairy cattle

    Molecular analysis of fungal communities and laccase genes in decomposing litter reveals differences among forest types but no impact of nitrogen deposition

    Full text link
    The fungal community of the forest floor was examined as the cause of previously reported increases in soil organic matter due to experimental N deposition in ecosystems producing predominantly high-lignin litter, and the opposite response in ecosystems producing low-lignin litter. The mechanism proposed to explain this phenomenon was that white-rot basidiomycetes are more important in the degradation of high-lignin litter than of low-lignin litter, and that their activity is suppressed by N deposition. We found that forest floor mass in the low-lignin sugar-maple dominated system decreased in October due to experimental N deposition, whereas forest floor mass of high-lignin oak-dominated ecosystems was unaffected by N deposition. Increased relative abundance of basidiomycetes in high-lignin forest floor was confirmed by denaturing gradient gel electrophoresis (DGGE) and sequencing. Abundance of basidiomycete laccase genes, encoding an enzyme used by white-rot basidiomycetes in the degradation of lignin, was 5–10 times greater in high-lignin forest floor than in low-lignin forest floor. While the differences between the fungal communities in different ecosystems were consistent with the proposed mechanism, no significant effects of N deposition were detected on DGGE profiles, laccase gene abundance, laccase length heterogeneity profiles, or phenol oxidase activity. Our observations indicate that the previously detected accumulation of soil organic matter in the high-lignin system may be driven by effects of N deposition on organisms in the mineral soil, rather than on organisms residing in the forest floor. However, studies of in situ gene expression and temporal and spatial variability within forest floor communities will be necessary to further relate the ecosystem dynamics of organic carbon to microbial communities and atmospheric N deposition.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72825/1/j.1462-2920.2007.01250.x.pd

    An evaluation of the stimulants and impediments to innovation within PFI/PPP projects

    Get PDF
    This paper identifies the theoretical stimulants and impediments associated with the implementation of PFI/PPP (Private Finance Initiative/Public Private Partnership) projects. A current defect of this procurement approach is the unintentional constraint upon the innovations incorporated into the development of PFI projects. A critical evaluation of the published literature has been utilized to synthesize a theoretical model. The paper proposes a theoretical model for the identification of potential innovation stimulants and impediments within this type of procurement. This theoretical model is then utilised to evaluate four previously completed PFI projects. These project case-studies have been examined in detail. The evaluation demonstrates how ineffective current procedures are. The application of this model before project letting could eliminate unintentional constraints and stimulate improved innovation within the process. The implementation of the model could improve the successful delivery of innovation within the entire PFI/PPP procurement process

    Higher bone resorption excretion in South Asian women vs. White Caucasians and increased bone loss with higher seasonal cycling of vitamin D: Results from the D-FINES cohort study

    Get PDF
    Few data exist on bone turnover in South Asian women and it is not well elucidated as to whether Western dwelling South Asian women have different bone resorption levels to that of women from European ethnic backgrounds. This study assessed bone resorption levels in UK dwelling South Asian and Caucasian women as well as evaluating whether seasonal variation in 25-hydroxyvitamin D [25(OH)D] is associated with bone resorption in either ethnic group. Data for seasonal measures of urinary N-telopeptide of collagen (uNTX) and serum 25(OH)D were analysed from n = 373 women (four groups; South Asian postmenopausal n = 44, South Asian premenopausal n = 50, Caucasian postmenopausal n = 144, Caucasian premenopausal n = 135) (mean (± SD) age 48 (14) years; age range 18–79 years) who participated in the longitudinal D-FINES (Diet, Food Intake, Nutrition and Exposure to the Sun in Southern England) cohort study (2006–2007). A mixed between-within subjects ANOVA (n = 192) showed a between subjects effect of the four groups (P < 0.001) on uNTX concentration, but no significant main effect of season (P = 0.163). Bonferroni adjusted Post hoc tests (P ≀ 0.008) suggested that there was no significant difference between the postmenopausal Asian and premenopausal Asian groups. Season specific age-matched-pairs analyses showed that in winter (P = 0.04) and spring (P = 0.007), premenopausal Asian women had a 16 to 20 nmol BCE/mmol Cr higher uNTX than premenopausal Caucasian women. The (amplitude/mesor) ratio (i.e. seasonal change) for 25(OH)D was predictive of uNTX, with estimate (SD) = 0.213 (0.015) and 95% CI (0.182, 0.245; P < 0.001) in a non-linear mixed model (n = 154). This showed that individuals with a higher seasonal change in 25(OH)D, adjusted for overall 25(OH)D concentration, showed increased levels of uNTX. Although the effect size was smaller than for the amplitude/mesor ratio, the mesor for 25(OH)D concentration was also predictive of uNTX, with estimate (SD) = − 0.035 (0.004), and 95% CI (− 0.043, − 0.028; P < 0.001). This study demonstrates higher levels of uNTX in premenopausal South Asian women than would be expected for their age, being greater than same-age Caucasian women, and similar to postmenopausal Asian women. This highlights potentially higher than expected bone resorption levels in premenopausal South Asian women which, if not offset by concurrent increased bone formation, may have future clinical and public health implications which warrant further investigation. Individuals with a larger seasonal change in 25(OH)D concentration showed an increased bone resorption, an association which was larger than that of the 25(OH)D yearly average, suggesting it may be as important clinically to ensure a stable and steady 25(OH)D concentration, as well as one that is high enough to be optimal for bone health

    Alpha scattering and capture reactions in the A = 7 system at low energies

    Get PDF
    Differential cross sections for 3^3He-α\alpha scattering were measured in the energy range up to 3 MeV. These data together with other available experimental results for 3^3He +α+ \alpha and 3^3H +α+ \alpha scattering were analyzed in the framework of the optical model using double-folded potentials. The optical potentials obtained were used to calculate the astrophysical S-factors of the capture reactions 3^3He(α,Îł)7(\alpha,\gamma)^7Be and 3^3H(α,Îł)7(\alpha,\gamma)^7Li, and the branching ratios for the transitions into the two final 7^7Be and 7^7Li bound states, respectively. For 3^3He(α,Îł)7(\alpha,\gamma)^7Be excellent agreement between calculated and experimental data is obtained. For 3^3H(α,Îł)7(\alpha,\gamma)^7Li a S(0)S(0) value has been found which is a factor of about 1.5 larger than the adopted value. For both capture reactions a similar branching ratio of R=σ(Îł1)/σ(Îł0)≈0.43R = \sigma(\gamma_1)/\sigma(\gamma_0) \approx 0.43 has been obtained.Comment: submitted to Phys.Rev.C, 34 pages, figures available from one of the authors, LaTeX with RevTeX, IK-TUW-Preprint 930540
    • 

    corecore