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131.
132.
Beth N. Orcutt Timothy D'Angelo C. Geoff Wheat Elizabeth Trembath-Reichert 《Environmental microbiology》2021,23(7):3923-3936
Subseafloor oceanic crust is a vast yet poorly sampled habitat for life. Recent studies suggest that microbial composition in crustal habitats is variable in space and time, but biogeographic patterns are difficult to determine due to a paucity of data. To address this, we deployed hundreds of mineral colonization experiments at and below the seafloor for 4–6 years at North Pond, a borehole observatory network in cool (<10°C) and oxic oceanic crust on the western flank of the Mid-Atlantic Ridge. The overall community composition of mineral incubations reveals that colonization patterns are site dependent, with no correlation to mineral type. Only a few members of the Thioalkalispiraceae and Thioprofundaceae exhibited a mineral preference pattern, with generally higher abundance on metal sulphides compared to silicates, while taxa of the Gammaproteobacteria and Deltaproteobacteria were common in the colonization experiments. In comparison to datasets from other crustal habitats, broader biogeographic patterns of crustal communities emerge based on crustal habitat type (surface-attached communities versus fluid communities), redox environment and possibly crustal age. These comparisons suggest successional biogeography patterning that might be used as an indicator of how recently permeable pathways were established within oceanic crust. 相似文献
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Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of preventable nosocomial infections and is endemic in hospitals worldwide. The effectiveness of infection control policies varies significantly across hospital settings. The impact of the hospital context towards the rate of nosocomial MRSA infections and the success of infection control is understudied. We conducted a modelling study to evaluate several infection control policies in surgical, intensive care, and medical ward specialties, each with distinct ward conditions and policies, of a tertiary public hospital in Sydney, Australia. We reconfirm hand hygiene as the most successful policy and find it to be necessary for the success of other policies. Active screening for MRSA, patient isolation in single-bed rooms, and additional staffing were found to be less effective. Across these ward specialties, MRSA transmission risk varied by 13% and reductions in the prevalence and nosocomial incidence rate of MRSA due to infection control policies varied by up to 45%. Different levels of infection control were required to reduce and control nosocomial MRSA infections for each ward specialty. Infection control policies and policy targets should be specific for the ward and context of the hospital. The model we developed is generic and can be calibrated to represent different ward settings and pathogens transmitted between patients indirectly through health care workers. This can aid the timely and cost effective design of synergistic and context specific infection control policies. 相似文献
136.
Harvesting of wildlife by humans is commonly known to impact target species’ demography, life history and behaviour. Yet in the context of invasive and pest species control, behavioural shifts have received very little attention. The introduced common myna, Acridotheres tristis, is undergoing intensive control efforts in some areas of its Australian distribution. In order to investigate whether myna populations respond to harvesting, we compared the behaviour of free-ranging common mynas in areas of high and low trapping pressure. Behavioural analyses revealed that mynas in high trapping risk areas stayed closer to refuges, tended to form smaller groups, and were overall less detectable. Behavioural differences between high and lowly trapped areas were not attributable to variation in population density. Overall, these results are consistent with the hypothesis that common mynas have the potential to adjust their behaviour in response to heightened anthropic risk in the environment. Behavioural shifts in invasive alien species could modify their ecological impact and may interfere not only with the effectiveness of control measures, but also with how their effectiveness is assessed. Future research should aim to isolate behavioural mechanisms underpinning compensatory responses to control so that any potential effects can be mitigated. 相似文献
137.
Kevin A. Wood Julia L. Newth Geoff M. Hilton Eileen C. Rees 《European Journal of Wildlife Research》2018,64(4):38
Assessments of body condition can provide useful information on changes in the state of individuals within a population, which may in turn help to inform conservation efforts. For example, decreases in body condition over time can indicate reduced food resources. Mass and skull length measures recorded for 195 adult and 467 first winter (cygnets) Bewick’s Swans (Cygnus columbianus bewickii) at wintering sites in the UK between winters 1966/1967 and 2017/2018 therefore were analysed to determine whether a ca. 40% decline in numbers in the Northwest European Bewick’s Swan population between 1995 and 2010 corresponded with poorer body condition from the mid-1990s onwards. Parents and siblings were known for all individuals, allowing us to account for shared genetic factors and rearing environment in our analysis. We used linear mixed-effects models and an information-theoretic approach to test different models of temporal variation in scaled body mass index (SBMI). Within our study population, although SBMI values varied both within and between years, we found no evidence of any directional trends in body condition. Of our competing time models of swan SBMI, a model in which age-specific body condition was constant over time received the greatest support in the data. Body condition was greater for adults than cygnets, but did not vary between sexes or wintering sites. Our findings suggest no connection between the recent declines in population size and body condition. Population decline is therefore unlikely to be caused by inadequate food supplies. 相似文献
138.
Hagai Levine Hideo Mohri Anders Ekbom Liliana Ramos Geoff Parker Eduardo Roldan Luca Jovine Sabine Koelle Anna Lindstrand Simone Immler Sharon Mortimer David Mortimer Gerhard van der Horst Sumio Ishijima Natalie Aneck-Hahn Elisabetta Baldi Roelof Menkveld Susan A Rothmann Aleksander Giwercman Yvonne Giwercman Mats Holmberg Ulrik Kvist Lars Björndahl Rebecka Holmberg Stefan Arver John Flanagan Joël R Drevet 《Andrologie》2018,28(1):13
On the occasion of the XIIIth International Symposium on Spermatology held from 9 to 13 May 2018 in Stockholm (Sweden), participants (guest speakers and audience) collectively felt the need to make a public statement on the general issue of male reproductive health. Our intention is to raise awareness of what we believe is a neglected area of research despite alarming situations around the world. The disclosure strategy desired by the co-authors is to bring it to the attention of the greatest number partly by considering co-publication in the various periodicals dealing with Reproductive Biology and Andrology. BaCA’s editorial office accepted this mission and found it natural that our periodical, the official journal of the French Andrology Society (SALF), should carry this message. 相似文献
139.
Impacts of the invasive fungus Austropuccinia psidii (myrtle rust) on three Australian Myrtaceae species of coastal swamp woodland 下载免费PDF全文
Laura Fernandez Winzer Angus J. Carnegie Geoff S. Pegg Michelle R. Leishman 《Austral ecology》2018,43(1):56-68
Exotic fungal pathogens can substantially affect individuals and populations of susceptible native plant species, potentially resulting in changes in community structure and composition. Austropuccinia psidii (myrtle rust) is a pathogenic fungus native to South America that affects species in the plant family Myrtaceae. The pathogen was introduced accidentally to Australia and first detected in NSW in April 2010. Ecological impacts have been poorly studied in the native range of A. psidii and even less in its Australian introduced range. In order to assess the potential impact of A. psidii on coastal swamp woodland, two glasshouse experiments were conducted using three co‐occurring species: Melaleuca quinquenervia, Leptospermum laevigatum and Baeckea linifolia. Plants of each species were grown individually (Experiment 1) and in mixed species assemblages (Experiment 2), with half inoculated with A. psidii and the other half remaining as controls. Infection level was assessed and impact on seedling survival and growth recorded. In both experiments L. laevigatum and M. quinquenervia seedlings were heavily infected and showed high degrees of susceptibility with negative effects on growth (height, biomass and number of leaves). In contrast, no B. linifolia seedling presented visible symptoms of disease, although seedlings showed reduced growth. Melaleuca quinquenervia seedlings had greater infection levels and suffered greater growth reductions than L. laevigatum in both experiments. However, there was no significant difference in the relative abundance of the three species in the mixed‐species experiment. This study provides a better understanding of the potential impacts of A. psidii in this vegetation community and has significant implications for the conservation and management of Australian Myrtaceae‐dominated plant communities generally. 相似文献
140.
A new species of Taeniastrotos is described from an ariid host, Cathrops spixii, caught in southern Brazil. It is the first member of the genus to be recorded from the Atlantic Ocean and can be distinguished from its four known congeners by the setation of the terminal endopodal segment of the fourth leg. 相似文献