190 research outputs found
The post-stocking behaviour of hatchery-reared brown troup (Salmo trutta L.)
Stocking, transfer and introductions of hatchery-reared salmonids are commonly used to enhance recreational or commercial fisheries and to preserve or re-establish threatened populations (Cowx, 1994). Whilst a lot of effort has been directed toward understanding the production and stocking methods of hatchery-reared salmonids, relatively little is known about the post-stocking survival and behaviour of these fish (Hickley, 1994). In particular there is little available information concerning the post-stocking dietary habits, dispersion
and behaviour of hatchery-reared brown trout; particularly following release into standing waters. Consequently, a study was instigated to examine the relative post-stocking dispersion and temporal changes in the diets of hatchery-reared brown trout released to support a commercial recreational fishery, Carron Valley Reservoir. Further laboratory studies examined if resident brown trout display a prior-resident competitive advantage over
stocked conspecifics, if hatchery-reared brown trout display non-cost effective aggressive behaviour and the short-term changes in the feeding efficiency of naive hatchery-reared brown trout when experiencing novel prey.
1000 commercially produced hatchery-reared brown trout were marked with a subcutaneous
alcian blue tattoo and released into Carron Valley Reservoir at the start of the 1999 fishing season. Stomach samples were taken from angler recaptured hatchery-reared fish along with consecutively captured resident brown trout. The diets of the two groups were compared to assess the relative post-stocking temporal changes in the diets of the hatchery-reared brown trout. This study found hatchery-reared brown trout to consume lower weights and numbers of prey, and they appeared to exhibit a preconditioned `look up' dietary response to surface prey immediately following release than resident conspecifics. It was further observed that although hatchery-reared brown trout did not immediately adapt to natural diets, their relative foraging efficiency increased over the sample period. In laboratory experiments naive hatchery-reared brown trout further demonstrated the improved feeding efficiency with experience.
1000 commercially produced hatchery-reared brown trout were tagged with a combination
of Visible Implant (VI) and `Floy' style tags prior to release during the 1998,1999 and 2000 fishing seasons. An angler survey programme was instigated to record the reported recapture positions of these tagged fish in order to assess the post-stocking gross dispersion patterns of hatchery-reared brown trout in Carron Valley Reservoir. A further 3 trout were radiotagged to elucidate the fine scale post-stocking dispersion of these fish. This study found hatchery-reared brown trout to disperse quickly from their respective release sites,
although over a relatively restricted area. Individual hatchery-reared brown trout were
observed to exhibit high levels of activity immediately following release, during which period they covered relatively large total distances within a relatively restricted area.
In an artificial stream environment, established wild brown trout displayed a prior-resident competitive advantage over later introductions of both hatchery-reared and wild conspecifics. Established wild fish initiated more aggressive acts and maintained home stations closer to a point source of feed than introduced trout. Introduced hatchery-reared brown trout were more aggressive and exhibited a lower mean specific growth rate than simultaneously stocked wild conspecifics, suggesting that excessive expenditure of energy for
unnecessary aggression may contribute to the poor post-stocking survival in hatchery-reared brown trout
The estimation of a preference-based measure of health from the SF-36
This paper reports on the findings of a study to derive a preference-based measure of health from the SF-36 for use in economic evaluation. The SF-36 was revised into a six-dimensional health state classification called the SF-6D. A sample of 249 states defined by the SF-6D have been valued by a representative sample of 611 members of the UK general population, using standard gamble. Models are estimated for predicting health state valuations for all 18,000 states defined by the SF-6D. The econometric modelling had to cope with the hierarchical nature of the data and its skewed distribution. The recommended models have produced significant coefficients for levels of the SF-6D, which are robust across model specification. However, there are concerns with some inconsistent estimates and over prediction of the value of the poorest health states. These problems must be weighed against the rich descriptive ability of the SF-6D, and the potential application of these models to existing and future SF-36 data set
Fixing the Election Process: Lessons Learned From States and Localities
America is currently ranked 30 out of 35 countries in voter turnout among its peers in the Organization for Economic Cooperation and Development. When you delve deeper, participation in American democracy appears even more problematic, as certain socioeconomic and demographic groups are significantly less likely to participate than others, potentially skewing results. Several new reforms are being implemented across the country in different states to help remedy these perceived problems. These changes have come in the form of new electoral systems such as Ranked Choice Voting (RCV), new public financing systems such as the Democracy Voucher program in Seattle and the nine-to-one matching funds program in New York City, the expansion of convenience voting across the country, and new voter ID laws. By implementing these reforms, governments intend to increase turnout and allow for more accurate and equitable participation. Opponents argue that these reforms are intended to sway elections in a partisan manner and will result in increased instances of voter fraud.
The research analyzes case studies in Maine, San Francisco, Seattle, New York City, and multiple other states and localities to determine the impact these reforms have had on voter turnout as a whole, as well as changes in turnout across different demographics and socioeconomic groups. This research finds that the implementation of RCV results in higher turnout, more cordial campaigns, and higher voter satisfaction. Additionally, both Seattle and New York City’s public financing methods are ultimately effective at increasing participation but are primarily utilized by groups that are traditionally already likely to participate. Finally, convenience voting measures such as Same Day Registration and All-Mail voting increase turnout but again are utilized primarily by those demographics who are already likely to participate. Beyond this, there is no evidence of increased instances of voter fraud as a result of these reforms. Ultimately, the thesis recommends that it would be beneficial for states and the federal government to implement these reforms to make American democracy more equitable
Developing low-cost household water supply options: the potential of self supply in Ethiopia
Ethiopia has launched a Universal Access Plan (UAP) to achieve safe water supply and sanitation for the
country’s 77 million people by 2012. This would mean providing safe water service to 50.9 million new
users in just 7 years. The government recently reviewed the progress of UAP and concluded that it would
be challenging to achieve its targets with the existing implementation approach. The review strongly
recommended that lowcost
options need to be pursued to accelerate progress. Self Supply is proposed to
be one such approach, providing safe water supply to households without external subsidy. This paper
briefly discusses the practice and potential of Self Supply approach; and proposes key next steps needed
to help achieve the UAP target for safe water supply in Ethiopia
The triple quasar Q1115+080A, B, C - A quintuple gravitational lens image
Spectroscopy and direct imaging of Qll 15+080A,B,C with a CCD camera supports the hypothesis that they are gravitational images of a single object. Spectroscopy of the C III] λ1909 emission line shows all the images to have identical spectra and redshifts (to within 100 km s^(-1)),
except that Bis slightly redder. The position and brightness of the three images has been accurately measured; the images A, B, and Care magnitudes 16.30,18.64, and 18.17, respectively, in the r band, B is 1". 77 from A in position angle 266°, and C is 2".28 away at position angle 322°. A and C have the same color, but B is redder by 0.23 mag in (g-r). There is no trace of a lens galaxy, which
must have a surface brightness of less than 29 mag arcsec^(-2) at a distance of 5" -8" from Q1115+080. Three bright galaxies lie near Q1115+080, apparently forming a small group. Gravitational lens imaging by a massive spiral galaxy is explored, and we find a quintuple image model
resembling Q1115+080 A,B,C. In this model, Q1115+080A is a highly magnified close pair of images oriented in position angle 23°. An elongation of Q1115+080A at this angle is seen in the CCD pictures
Designing water supply and sanitation projects to meet demand in rural and peri-urban communities - Book 2: Additional notes for policy makers and planners
These guidelines are the result of two years collaborative research undertaken by WEDC with partners in Africa and South Asia. They demonstrate how water supply and sanitation projects in rural and peri-urban areas can be designed to meet user demand. The aim is to improve the use and sustainability of the services provided. The guidelines consist of three books: Book 1: Concept, Principles and Practice, Book 2: Additional Notes for Policy Makers and Planners, Book 3: Ensuring the Participation of the Poor. This book has been written for policy makers and planners responsible for water supply and sanitation in rural and peri-urban areas. Potential readers include government staff at national, state and local levels, senior managers in non-governmental organisations and the private sector, and donor staff and advisers. This book supplements Book 1 of these guidelines. Readers should ensure they are familiar with the contents of Book 1 before reading this volume
Designing water supply and sanitation projects to meet demand in rural and peri-urban communities - Book 3: Ensuring the participation of the poor
These guidelines are the result of two years collaborative research undertaken by WEDC with partners in Africa and South Asia. They demonstrate how water supply and sanitation projects in rural and peri-urban areas can be designed to meet user demand. The aim is to improve the use and sustainability of the services provided.The guidelines consist of three books: Book 1: Concept, Principles and Practice, Book 2: Additional Notes for Policy Makers and Planners, Book 3: Ensuring the Participation of the Poor. This booklet is designed to be read in conjunction with books 1 and 2 of the Designing to Meet Demand guidelines. Whilst these describe a number of practical approaches, this third booklet focuses on a single albeit very important issue: how to ensure the participation of the poor within a demand responsive approach. If this is not done, those in most need of improved services stand every chance of being further marginalised
Designing water supply and sanitation projects to meet demand in rural and peri-urban communities - Book 1: Concept, principles and practice
These guidelines are the result of two years collaborative research undertaken by WEDC with partners in Africa and South Asia. They demonstrate how water supply and sanitation projects in rural and peri-urban areas can be designed to meet user demand. The aim is to improve the use and sustainability of the services provided. The guidelines consist of three books: Book 1: Concept, Principles and Practice Book, 2: Additional Notes for Policy Makers and Planners, Book 3: Ensuring the Participation of the Poor. Concepts, Principles and Practice is intended for practitioners - engineers, social facilitators, financial specialists and managers - implementing water supply and sanitation projects in rural and peri-urban areas. This book is divided into two parts. The concept of demand is introduced in Part I, explaining what demand is and how it can be used to guide project design. Part II shows how the concept and principles described in Part I can be translated into practice, ensuring that vulnerable groups are included in the process
Evolution FP7 funded project: body structure design strategies using new composite and aluminium materials and enabled technologies
Based on Pininfarina Nido EV concept, EVolution aims to reduce the vehicle weight through new materials and process technologies, focused on five demonstrators: underbody, front crossbeam, mechanical subframe, shotgun system and door. This paper refers to body structure design strategies using new composite, Al materials and enabled technologies, focusing in particular on demonstrators design and manufacturing. The new front crossbeam geometry of the front shell is adapted starting from the Nanotough design, while the rear shell is specific for EVolution. The subframe demonstrator is redesigned to fulfil mechanical requirements of the part and manufacturing feasibility either. The EVolution door concept consists of two semistructural composite skins including a structural Al frame. The underbody is conceived through an integrated approach, optimising each element for its function. The shotgun component is designed to link parts obtained with different manufacturing technologies and several aluminium alloys in one single component: the structural node demonstrator.The research leading to these results has received funding from the European Union
Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 314744
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