2,261 research outputs found
Mechanisms of NOx formation and control: alternative and petroleum-derived liquid fuels
Journal ArticlePetroleum-, coal- and shale-derived liquid fuels were burned in a downfired tunnel furnace to assess the impact of fuel properties on the formation and control of NOx emissions. A nitrogen-free oxidant mixture (Ar, C02 , 02) was used to isolate fuel NOx formation. Under excess air conditions fuel NOx correlated well with total fuel nitrogen content for both the petroleum and alternate fuels. Under staged combustion conditions the influence of fuel nitrogen content was much less pronounced but equally highly correlated except in the case of a coal-derived liquid
Imaging of canine neoplastic reproductive disorders
Diagnostic imaging plays an essential role in the diagnosis and management of reproductive neoplasia in dogs and cats. The initial diagnosis, staging, and planning of surgical and ra-diation treatment and the response to therapy all involve imaging to varying degrees. Routine ra-diographs, ultrasound, nuclear medicine, and crossâsectional imaging in the form of computed tomography (CT) and magnetic resonance imaging (MRI) are routinely used in canine reproductive disorders. The choice of imaging modality depends on many factors, including the level of referral and the pathological information required. The biological behaviour of the tumour also guides the choice of imaging in cancer staging, and imaging may play an important role in guiding serial tumour biopsy during the course of therapy. The sophistication of imaging modalities is in-creasing exponentially. Each modality has advantages and disadvantages in terms of cost, availa-bility, sensitivity, specificity, and qualities of anatomic versus functional imaging
Veterinary practitionersâ selection of diagnostic tests for the primary evaluation of colic in the horse
The aim of this study was to survey veterinary practitionersâ selection of diagnostic tests for horses with clinical signs of abdominal pain. A questionnaire was distributed to veterinary surgeons involved in the primary evaluation of horses with abdominal pain, including the respondent's demographics, selection of diagnostic tests and factors affecting decision-making. Data analysis included descriptive analysis, categorisation of free text and simple univariable correlations to explore the relationships between independent variables and the relative self-estimated frequency that diagnostic tests were performed. A total of 228 responses were analysed. Participants worked in mixed practice (55.7 per cent), first opinion equine (22.8 per cent), first and second opinion equine (17.9 per cent) and referral practice (3.1 per cent). The majority (48.2 per cent, 105/218) were very confident managing a colic case (confidence level 4/5). The most frequently used diagnostic tests were âresponse to analgesiaâ (87.2±24.0 per cent cases), rectal examination (75.9±21.2 per cent) and nasogastric intubation (43.8±27.6 per cent). Approach varied between practitioners, and for all diagnostic tests with frequency of use ranging from 0 to 100 per cent of cases. âRisk to personal safetyâ was the most common reason for not using rectal examination. Practitioner's opinion of their confidence level in managing a colic case was associated with how frequently they used different diagnostic tests. There was marked variation in practitionersâ approaches, highlighting the need for further evidence to support decision-making
Ultrasonography of the prostate gland and testes in dogs
Ultrasonographic imaging is an important diagnostic tool because it allows assessment of the shape, size, position, margination and internal architecture of organs, as well as facilitating the study of vascular supply and vascularisation. Recently, there has been considerable development of B-mode, Doppler and contrast-enhanced ultrasonography for examination of the reproductive tract of dogs, both for studying normal physiology and in the clinical setting. This article describes the practical examination of the canine prostate gland and testes using a variety of ultrasound techniques, and details the normal appearance and blood flow of these organs as well as changes that may be observed with common reproductive disorders
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To be or not to be an auctioneer: Some thoughts on the legal nature of online eBay auctions and the protection of consumers
This paper discusses the legal classification of online âeBayâ auctions. The discussion has key implications on the scope of consumer protection law as sale by auctions are, for example, excluded from the scope of the Consumer Protection (Distance Selling) Regulations 2000. The paper uncovers that online âeBayâ auctions cannot always be considered as traditional auctions and that eBay, as an intermediary, is not to be considered as an auctioneer. This creates difficulties associated with a distributive application of consumer protection laws such as the Consumer Protection (Distance Selling) Regulations 2000. Another set of difficulties is associated with a lenient legal regime applicable to the liability of eBay under the Electronic Commerce (EC Directive) Regulations 2002 . The paper concludes that there is an urgent need to clarify the legal classification of online auctions and to rethink the liability of online auction sites to better protect consumers
Environmental chemicals in dog testes reflect their geographical source and may be associated with altered pathology
In humans and dogs, a temporal decline in semen quality and increased incidence of testicular cancer is hypothesised to be associated with exposure to anthropogenic chemicals, particularly during fetal development. Human studies suggest that differential exposures to environmental chemicals may be associated with geographical differences in male reproductive health. Here we investigate testicular chemical profiles and pathologies in dogs residing in the UK [West Midlands (WM), East Midlands (EM), South East (SE)], Denmark (Copenhagen) and Finland (Vantaa). Testes, surplus from routine castrations, contained region specific differences in relative concentrations of diethylhexyl phthalate (DEHP), polybrominated diphenyl ethers (PBDE) and polychlorinated biphenyls (PCB). Relative to UK regions, testes from dogs living in Finland and Denmark had higher concentrations of PBDE and lower concentrations of DEHP and PCBs. Regional differences in the UK in PCB concentrations were also observed. Dog testes from Finland had fewer pathologies, reduced testicular area stained for Sertoli and germ cells and evidence of reduced cellular proliferation. Since the geographical differences in testis pathologies in dogs parallel reports of regional differences in human testicular cancer, we postulate that this may reflect chemical effects within the testis and that this may be related to environmental influences on male reproductive function.Peer reviewe
Going places
Journeys. We all make them. Often they take us to exotic places. Sometimes they take us even further. They might take us through time. Or they might take us into a new way of life. There are times too, when we go all over the world and back again only to find that home is, after all, where itâs all happening.
This book contains stories about many different types of journey. We hope you will enjoy travelling into it and finding a world that suits you
Characterization of the material response in the granular ratcheting
The existence of a very special ratcheting regime has recently been reported
in a granular packing subjected to cyclic loading \cite{alonso04}. In this
state, the system accumulates a small permanent deformation after each cycle.
After a short transient regime, the value of this permanent strain accumulation
becomes independent on the number of cycles. We show that a characterization of
the material response in this peculiar state is possible in terms of three
simple macroscopic variables. They are defined that, they can be easily
measured both in the experiments and in the simulations. We have carried out a
thorough investigation of the micro- and macro-mechanical factors affecting
these variables, by means of Molecular Dynamics simulations of a polydisperse
disk packing, as a simple model system for granular material. Biaxial test
boundary conditions with a periodically cycling load were implemented. The
effect on the plastic response of the confining pressure, the deviatoric stress
and the number of cycles has been investigated. The stiffness of the contacts
and friction has been shown to play an important role in the overall response
of the system. Specially elucidating is the influence of the particular
hysteretical behavior in the stress-strain space on the accumulation of
permanent strain and the energy dissipation.Comment: 13 pages, 20 figures. Submitted to PR
BMQ
BMQ: Boston Medical Quarterly was published from 1950-1966 by the Boston University School of Medicine and the Massachusetts Memorial Hospitals
Enhancing the early student experience
This paper is concerned with identifying how the early student experience can be enhanced in order to improve levels of student retention and achievement. The early student experience is the focus of this project as the literature has consistently declared the first year to be the most critical in shaping persistence decisions. Programme managers of courses with high and low retention rates have been interviewed to identify activities that appear to be associated with good retention rates. The results show that there are similarities in the way programmes with high retention are run, with these features not being prevalent on programmes with low retention. Recommendations of activities that appear likely to enhance the early student experience are provided
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