1,723,147 research outputs found
β-diversity of deep-sea holothurians and asteroids along a bathymetric gradient (NE Atlantic)
Full text linkMeasuring and understanding patterns of ?-diversity remain major challenges in community ecology. Recently, ?-diversity has been shown to consist of 2 distinct components: (1) spatial turnover and (2) species loss leading to nestedness. Both components structure deep-sea macrofaunal assemblages but vary in importance among taxa and ocean basins and with energy availability. Here, we present the first evidence for turnover and nestedness along a bathymetric gradient in 2 major megafaunal taxa, holothurians and asteroids. Turnover is the dominant component of ?-diversity throughout bathyal and abyssal zones in both taxa, despite major differences in ?-diversity and trophic composition. High spatial turnover suggests a role for evolutionary adaptation to environmental circumstances within depth bands. This pattern differs fundamentally from those in some macrofaunal groups in low-energy environments where abyssal nestedness is high and diversity low, with diversity maintained partly by source-sink dynamics
Long-term change in the abyssal NE Atlantic: The ‘Amperima Event’ revisited
Full text linkThe results from a time series study (1989–2005) at a depth of 4850 m on the Porcupine Abyssal Plain, NE Atlantic, are presented, showing radical changes in the density of large invertebrates (megafauna) over time. Major changes occurred in a number of different taxa between 1996 and 1999 and then again in 2002. One species of holothurian, Amperima rosea, was particularly important, increasing in density by over three orders of magnitude. There were no significant changes in total megafaunal biomass during the same period. Peaks in density were correlated to reductions in mean body size, indicating that the increases were related to large-scale recruitment events. The changes occurred over a wide area of the Porcupine Abyssal Plain. Comparisons made with changes in the density of protozoan and metazoan meiofauna, and with macrofauna, showed that major changes in community structure occurred in all size fractions of the benthic community at the same time. This suggests that the faunal changes were driven by environmental factors rather than being stochastic population imbalances of one or two species. Large-scale changes in the flux of organic matter to the abyssal seafloor have been noted in the time series, particularly in 2001, and may be related to the sudden mass occurrence of A. rosea the following year. Time-varying environmental factors are important in influencing the occurrence of megafauna on the abyssal seafloor
The ergonomics and design of an inclusive best-fit solution to workbenches
No full textThis thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.In a time when the developed world, is trying to reduce the human and economic
costs of musculo-skeletal disorders (MSDs), any contribution to such an endeavour
would be welcome. These economic costs are estimated to be in the tens of billions of
Euro in the EU countries and similarly in the USA, the cost in human pain has not
been measured. It may surprise many that in spite of all the advancements in science
and technology, that two generations of people, who are very significantly taller than the people of a century ago, are still working in industry and in education at benches, which have not changed, either in height or design in centuries. Some, like wheelchair users do not have the opportunity to work at a bench at all. At the outset this research project, had the primary objective of determining an ergonomic best-fit, for a broad range of users of workbenches. These included the young school going population (12-13 year olds), the senior students (16 plus years old), adults, and a cohort of surrogate wheelchair users. The research also endeavoured to determine if adolescents, who were of the same stature as adults, had the same workbench ergonomics requirements. The secondary objective, which was completely dependant on the first, was to design a bench, which would suit the
ergonomic requirements of this diverse group.
The research has identified the best-fit workbench heights for the total cohort, while
recognising the individual differences in relation to bench height ergonomics, for each
of the sub-groups tested. The findings of the research have shown, that using surrogate wheelchair users to determine ergonomic data for this type of activity is fully justified. In combining the raw data for a similar number of wheelchair users, a best-fit bench height has been confirmed at 100 mm above knee height. There are no significant differences between the
ergonomic requirements for males and females at workbenches. Body part discomfort has been reduced significantly, for the wheelchair users, at the identified height and endurance has been extended. Importantly the career options for wheelchair users
have been extended, empowering them to make broader career choices. The outcomes of the research relating to three groups making up the able-bodied cohort have shown that an ergonomic best-fits possible, which suits the needs of this diverse group. A height of 150 mm under elbow height has been identified as best-fit, and this reduces the discomfort considerably while extending endurance. Robust working heights have been identified, but the female working heights at
workbenches, are not as robust as for the males. For all groups it has been shown that bench height has a significant effect on body part discomfort and endurance, and while there were differences in efficiency, which were not quite significant, it is suggested that working in an ergonomically compromising position must, in the long term, in addition to increasing the risk of MSDs, likely also influence productivity, and quality of work. An inclusive test-workbench has been designed and built which satisfies the ergonomic needs of the diverse user group described above
Billett, S, VX53189
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/371790Surname: BILLETT
Given Name(s) or Initials: S
Military Service Number or Last Known Location: VX53189
Missing, Wounded and Prisoner of War Enquiry Card Index Number: 37984182710
Item: [2016.0049.04117] "Billett, S, VX53189
RRS Charles Darwin Cruise 179, 14 Apr - 17 May 2006. Hotspot ecosystem research in the Setúbal, Lisbon, Cascais and Nazaré canyons on the Portuguese continental margin
Full text linkRRS Charles Darwin Cruise 179 was one of a series of cruises studying the biology, geology, biogeochemistry and physical oceanography of the Portuguese margin canyons. The cruise contributed to the European Union Framework Programme VI Integrated Project HERMES (Hotspot Ecosystem Research on the Margins of European Seas). Four key canyon areas on the European margin are being studied in HERMES: the Portuguese margin, the Irish margin and the Western and Eastern Mediterranean. On the Portuguese margin four canyons had been selected for multidisciplinary studies by the HERMES community: the Nazaré Canyon, Setúbal Canyon, Lisbon Canyon and the Cascais Canyon.RRS Charles Darwin cruise 179 was divided into two legs (Cartagena to Lisbon, 14 April to 1 May 2006; Lisbon to Falmouth, 1 to 17 May 2006). Leg 1 focused on the upper and middle parts of the Setúbal and Lisbon canyons, which join together at a depth of about 2000m, and the upper and middle Cascais Canyon. Leg 2 sampled the lower Cascais and Setúbal canyons and a wide variety of depths in the Nazaré Canyon. The principal sampling activities were seabed photographic and video imaging (NOCS SHRIMP system), deep-tow 30 kHz sidescan sonar imaging (NOCS TOBI system), coring (Megacorer, Piston Corer and Box Corer), trawling (Agassiz Trawl), and benthic boundary layer particulate biogeochemistry using CTD-mounted Stand Alone Pump Systems (SAPS).Seabed photo-transects at depths between 300 and 4500m confirmed that large parts of all the canyons were covered in a sediment drape, with little evidence of epifaunal megafauna within the canyon axis, but with localised communities of suspension feeding sponges, cnidarians (soft and stony corals), crinoids and asteroids on rocky ledges around the thalweg (central channel) of the canyons. Photo-transects across the thalwegs of the canyons revealed fascinating changes in the nature of the seabed (e.g. ripple patterns) and fauna (e.g. xenophyophores (giant protozoans) on the flanks of the Nazaré Canyon thalweg). New sidescan sonar images were obtained of the Lisbon and Cascais canyons and the base of the continental slope in the vicinity of the Cascais and Setúbal canyons. Coring and trawling focused on comparable sites at c. 3400m and 4400m in the lower canyons. Burrowing holothurians were evident in all three canyons at c. 3400m, but only in the Nazaré Canyon were they superabundant.This was the penultimate scientific cruise of RRS Charles Darwin. The ship has given UK and European marine science many years of excellent service. She will be greatly missed, and will be succeeded by RRS James Cook in 2006
Billett, R V, NX19642
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/371788Surname: BILLETT
Given Name(s) or Initials: R V
Military Service Number or Last Known Location: NX19642
Missing, Wounded and Prisoner of War Enquiry Card Index Number: 4070182708
Item: [2016.0049.04115] "Billett, R V, NX19642
Learning Across Working Life: Educative Experiences
No full textKnowing more fully what constitutes learning across working life and how negotiating transitions might be best supported and guided is important for working age adults, their workplaces, and communities. Central to that negotiation are the experiences that adults are afforded and how they engage with them. Drawing on an investigation of adult Australians’ worklife learning, the concept of educative experiences emerged as an explanatory basis for elaborating, understanding and supporting that learning. That is, the range of experiences that are educative in so far as they afford opportunities, support participation, and guide and augment that learning. These experiences are more expansive and inclusive than those afforded through (lifelong) educational programs and being taught or facilitated by others as intentional learning experiences. Together, with the concept of personal curriculum (see Billett, S. (this volume). Learning across working life: A product of ‘personal curriculum’. In S. Billett, H. Salling-Olesen & L. Filliettaz (Eds.), Sustaining employability through work-life learning: Practices and policies. Springer Nature), these explanatory bases offer ways to capture and understand what constitutes learning through experiences across working life. The aim of this chapter is to reappraise what constitutes lifelong education, advance a broader concept and position it more inclusively with the societal affordances that support and guide adults learning and development, drawing on data from 66 worklife history interviewsNo Full Tex
Billett, B H, TX3756
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/371789Surname: BILLETT
Given Name(s) or Initials: B H
Military Service Number or Last Known Location: TX3756
Missing, Wounded and Prisoner of War Enquiry Card Index Number: 30370182709
Item: [2016.0049.04116] "Billett, B H, TX3756
The sustained observatory over the Porcupine Abyssal Plain (PAP): Insights from time series observations and process studies (preface)
No full textOceanographic research in the past 20 years has highlighted the importance of understanding decadal-scale variation in the oceans in order to predict how the ocean will respond to climate change. Climate factors control many of the processes that regulate the input of nutrients to the euphotic zone, primary productivity, zooplankton responses, the downward flux of organic matter, the biomass and composition of seabed communities and, ultimately, the burial of carbon in deep-sea sediments. A critical part of our understanding of the interdependence of these many elements comes from long-term Eulerian observations, such as the Hawaii Ocean Time series (HOT) (Karl et al., 2003), the Bermuda Atlantic Time Series (BATS) (Steinberg et al., 2001), the NE Pacific Station M (Smith and Druffel, 1998) and the NE Atlantic Porcupine Abyssal Plain site (PAP) ([Billett and Rice, 2001] and [Lampitt et al., 2001]). Each time series site is considered as representing a different oceanic setting and each has a different suite of observations and history. However, the unifying theme of them all is to understand the time varying properties and processes of the oceanic environment. Only at Station M and PAP have water column and seabed observations been integrated, a feature of some considerable advantage. This special issue presents the latest work at PAP
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