235 research outputs found

    Can competition with pasture be used to manipulate bellyache bush (Jatropha gossypiifolia L.) population biology?

    Get PDF
    Bellyache bush (Jatropha gossypiifolia L.) is an invasive weed that poses economic and environmental problems in northern Australia. Competition between pasture and bellyache bush was examined in North Queensland using combinations of five pasture treatments (uncut (control); cut as low, medium, and high pasture; and no pasture) and four bellyache bush densities (0, 2, 6 and 12plantsm(-2)) in a buffel grass (Cenchrus ciliaris L.) dominated pasture. The pasture treatments were applied approximately once per year but no treatments were applied directly to the bellyache bush plants. Measurements of bellyache bush flowering, seed formation, and mortality were undertaken over a 9-year period, along with monitoring the pasture basal cover and plant species diversity. Maximum flowering rates of bellyache bush occurred after 9 years (97%) in plots containing no pasture, with the lowest rates of 9% in uncut control plots. Earliest flowering (322 days after planting) and seed formation (411 days) also occurred in plots with no pasture compared with all other pasture treatments (range 1314-1393 days for seed formation to occur). No seeds were produced in uncut plots. At the end of 9 years, mortality rates of bellyache bush plants initially planted averaged 73% for treatments with some pasture compared with 55% under the no-pasture treatment. The percentage of herbaceous plant basal cover in uncut plots was increased 5-fold after 9 years, much greater than the average 2% increase recorded across the low, medium, and high pasture treatments. The number of herbaceous species in uncut plots remained largely unchanged, whereas there was an average reduction of 46% in the cut pasture treatments. Buffel grass remained the species with the greatest basal cover across all cut pasture treatments, followed by sabi grass (Urochloa mosambicensis (Hack.) Dandy) and then red Natal grass (Melinis repens (Willd.) Ziska). These results suggest that grazing strategies that maintain a healthy and competitive pasture layer may contribute to reducing the rate of spread of bellyache bush and complement traditional control techniques such as the use of herbicides

    Postdischarge symptoms and rehabilitation needs in survivors of COVID‐19 infection: A cross‐sectional evaluation

    Get PDF
    Background: There is currently very limited information on the nature and prevalence of post‐COVID‐19 symptoms after hospital discharge. Methods: A purposive sample of 100 survivors discharged from a large University hospital were assessed 4 to 8 weeks after discharge by a multidisciplinary team of rehabilitation professionals using a specialist telephone screening tool designed to capture symptoms and impact on daily life. EQ‐5D‐5L telephone version was also completed. Results: Participants were between 29 and 71 days (mean 48 days) postdischarge from hospital. Thirty‐two participants required treatment in intensive care unit (ICU group) and 68 were managed in hospital wards without needing ICU care (ward group). New illness‐related fatigue was the most common reported symptom by 72% participants in ICU group and 60.3% in ward group. The next most common symptoms were breathlessness (65.6% in ICU group and 42.6% in ward group) and psychological distress (46.9% in ICU group and 23.5% in ward group). There was a clinically significant drop in EQ5D in 68.8% in ICU group and in 45.6% in ward group. Conclusions: This is the first study from the United Kingdom reporting on postdischarge symptoms. We recommend planning rehabilitation services to manage these symptoms appropriately and maximize the functional return of COVID‐19 survivors

    Signatures of Star-planet interactions

    Full text link
    Planets interact with their host stars through gravity, radiation and magnetic fields, and for those giant planets that orbit their stars within ∌\sim10 stellar radii (∌\sim0.1 AU for a sun-like star), star-planet interactions (SPI) are observable with a wide variety of photometric, spectroscopic and spectropolarimetric studies. At such close distances, the planet orbits within the sub-alfv\'enic radius of the star in which the transfer of energy and angular momentum between the two bodies is particularly efficient. The magnetic interactions appear as enhanced stellar activity modulated by the planet as it orbits the star rather than only by stellar rotation. These SPI effects are informative for the study of the internal dynamics and atmospheric evolution of exoplanets. The nature of magnetic SPI is modeled to be strongly affected by both the stellar and planetary magnetic fields, possibly influencing the magnetic activity of both, as well as affecting the irradiation and even the migration of the planet and rotational evolution of the star. As phase-resolved observational techniques are applied to a large statistical sample of hot Jupiter systems, extensions to other tightly orbiting stellar systems, such as smaller planets close to M dwarfs become possible. In these systems, star-planet separations of tens of stellar radii begin to coincide with the radiative habitable zone where planetary magnetic fields are likely a necessary condition for surface habitability.Comment: Accepted for publication in the handbook of exoplanet

    Searching for star-planet magnetic interaction in CoRoT observations

    Full text link
    Close-in massive planets interact with their host stars through tidal and magnetic mechanisms. In this paper, we review circumstantial evidence for star-planet interaction as revealed by the photospheric magnetic activity in some of the CoRoT planet-hosting stars, notably CoRoT-2, CoRoT-4, and CoRoT-6. The phenomena are discussed in the general framework of activity-induced features in stars accompanied by hot Jupiters. The theoretical mechanisms proposed to explain the activity enhancements possibly related with hot Jupiter are also briefly reviewed with an emphasis on the possible effects at photospheric level. The unique advantages of CoRoT and Kepler observations to test these models are pointed out.Comment: Invited review paper accepted by Astrophysics and Space Science, 13 pages, 5 figure

    To what extent can online mapping be decolonial? A journey throughout Indigenous cartography in Canada

    Get PDF
    In this paper, we describe and reflect upon our journey through Indigenous online mapping in Canada. This journey has been planned according to an academic goal: assessing the potential of online cartography for decolonial purposes. To reach this goal, we have followed methodological directions provided by Indigenous scholar Linda Tuhiwai Smith to review 18 Indigenous web-mapping sites across Canada. Supported by a series of ten interviews, this content analysis enabled us to sketch some of the contours of contemporary Indigenous cartography. On one hand, Indigenous communities largely control the data that are shared on these websites. They also partially control the way these data are represented through the mobilization of digital storytelling technologies that are better aligned with Indigenous ways of envisioning relationships to places than conventional maps. On the other hand, they do not have much control over the technological aspects of these projects, for which they remain heavily dependent on non-Indigenous partners. Throughout this journey, we noticed that women’s voices remained marginal in most of these mapping projects, but we also identified evidence supporting the idea that these voices are starting to play a vital role in the on-going effort of decolonizing mapping processes

    Transgressing the moral economy: Wheelerism and management of the nationalised coal industry in Scotland

    Get PDF
    This article illuminates the links between managerial style and political economy in post-1945 Britain, and explores the origins of the 1984–1985 miners' strike, by examining in longer historical context the abrasive attitudes and policies of Albert Wheeler, Scottish Area Director of the National Coal Board (NCB). Wheeler built on an earlier emphasis on production and economic criteria, and his micro-management reflected pre-existing centralising tendencies in the industries. But he was innovative in one crucial aspect, transgressing the moral economy of the Scottish coalfield, which emphasised the value of economic security and changes by joint industrial agreement

    An investigation into E-business service in the UK telecommunication manufacturing industry

    Get PDF
    Nowadays, suppliers’ product and service quality has risen in importance with a manufacturer’s push to develop core competencies and capitalise on global operations and markets. However, due to the complex features of business service, suppliers are facing significant challenges in providing service effectively and developing business collaboration. This is further complicated by the development of information and communication technologies (ICTs). This paper thus attempts to investigate the factors influencing buyers’ e-service (EBS) requirements and the impact of these requirements on business collaboration. Based on a questionnaire survey with 500 UK telecommunication manufacturers, this research identifies buyers’ different EBS requirements for different types of suppliers and the impact of ICTs on EBS requirements. While for suppliers our findings provide insights into buyers’ EBS requirements, they can help buyers to develop appropriate supplier selection criteria. The findings also contribute to a better understanding of the development of buyer and supplier business collaboration

    Geochemical Sourcing of New Zealand Obsidians by Portable X-Ray Fluorescence from 2011 to 2018

    Get PDF
    This dataset includes 4,582 obsidian artefacts matched to their natural geological source from 45 archaeological sites in New Zealand (Aotearoa). It is a compilation of a number of independent projects conducted in the laboratories of the University of Auckland and University of Otago from 2011 to 2018 [1–13]. It combines previously published studies [3, 5–13], an MA thesis [1], a BA(Hons) dissertation [2], a site report [4], and other previously unpublished primary data. The dataset has high reuse potential for future non-destructive studies of artefacts and social network analyses.   Funding statement: This database began as part of a project funded by Royal Society of New Zealand Marsden Grant (UOA1619) and the support of Te PĆ«naha Matatini

    Sensitivity to Gravitational Waves from Compact Binary Coalescences Achieved during LIGO's Fifth and Virgo's First Science Run

    Get PDF
    We summarize the sensitivity achieved by the LIGO and Virgo gravitational wave detectors for compact binary coalescence (CBC) searches during LIGO's fifth science run and Virgo's first science run. We present noise spectral density curves for each of the four detectors that operated during these science runs which are representative of the typical performance achieved by the detectors for CBC searches. These spectra are intended for release to the public as a summary of detector performance for CBC searches during these science runs.Comment: 12 pages, 5 figure
    • 

    corecore