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The moisture content of keratinous materials such as hoof horn is important as the presence of moisture has an inverse relationship on the mechanical properties of hoof horn and may have a subsequent effect on the function of the hoof. Methods previously used to dehydrate samples to calculate the moisture content of hoof horn vary considerably (Hopegood, 2002). Subsequent comparison of results is therefore unreliable. A comparison of different methods of dehydrating hoof horn was therefore carried out to establish a standardised protocol for dehydrating hoof horn to assess its moisture content. The moisture content of donkey hoof horn from normal animals and those with laminitis has not been reported. Maclean (1971) established that the moisture content of cattle suffering from laminitis was significantly higher than normal hooves. The resultant standardised protocol from the first part of this study was then used to compare the moisture content of hoof horn samples taken from horses, donkeys and those donkeys that had suffered from laminitis.
Advances in human genetics and genomics are beginning to move outside the traditional realm of medicine and into the classroom. How will educational officials react when asked to incorporate personalized genomic information into the educational program? This volume bridges the divide between science, education and ethics around the emergent integration of genomics and education. By pairing comprehensive analysis of the issues with primers on the underlying science, the authors put all relevant parties on a level field to facilitate thorough consideration and educated discussion regarding how to move forward in this new era, as well as how best to support the future of education and the future of all students. The volume is unique in bringing together not only scholarly experts but also parents and laypersons. In doing so, it gives voice and understanding to a broad spectrum of disciplines that have a stake in the future of education.
We have obtained 295 new radial velocities for the 112 giants in the globular cluster M3 previously observed by Gunn and Griffin. Our velocities have a typical accuracy of 0.8 km/s per measurement and have been combined with the Gunn and Griffin data in order to search for radial velocity variations over a time span of ten years. We find no convincing evidence that any of the giants observed are spectroscopic binaries with one notable exception, von Zeipel 164, which we believe is the first spectroscopic binary to be found in a globular cluster. Modelling of the velocity variations that would be expected in our data for a variety of binary populations confirms Gunn and Griffin's conclusion that binaries with separations of less than 10 AU must occur much less frequently among the giants of M3 than among the population I field stars.
Metallicities have been determined for a chemically unbiased sample of field halo dwarf stars. Their metallicity distribution function is similar to the predictions of a simple model of chemical evolution, but somewhat different from that of globular clusters.
Of all the different methods employed to estimate the mean absolute magnitude of RR Lyrae variables, only an analysis of the Baade-Wesselink type can determine this quantity directly. The distance to a globular cluster can therefore be measured by determining <MV>RR for that cluster instead of being forced to assume that <MV>RR is the same as that of the nearby field variables. This is important in that the field stars may have a different luminosity than cluster variables. In addition, since <MV>RR should depend on the composition (especially helium) and history of mass loss of these stars, this quantity may vary from cluster to cluster.
Binary stars appear to be a pervasive feature of the sidereal universe. In every stellar population or habitat that has been investigated, except globular clusters, from 10 to 40 percent of the objects observed prove to have variable radial velocities that suggest they are spectroscopie binaries. To extend the search for spectroscopie binaries in the globular cluster M3, we have obtained more than 300 new radial velocities for the 111 giants previously observed by Gunn and Griffin (1979). For one of the stars, von Zeipel 164, four observations spanning ten years show a velocity variation with an amplitude of at least 18 km s−1 and a period of perhaps a few years. We believe this is a strong candidate for the first spectroscopie binary to be found in a globular cluster.
Social context has a major influence on the detection and treatment of youth mental and substance use disorders in socioeconomically disadvantaged urban areas, particularly where gang culture, community violence, normalisation of drug use and repetitive maladaptive family structures prevail. This paper aims to examine how social context influences the development, identification and treatment of youth mental and substance use disorders in socioeconomically disadvantaged urban areas from the perspectives of health care workers.
Semi-structured interviews were conducted with health care workers (n=37) from clinical settings including: primary care, secondary care and community agencies and analysed thematically using Bronfenbrenner’s Ecological Theory to guide analysis.
Health care workers’ engagement with young people was influenced by the multilevel ecological systems within the individual’s social context which included: the young person’s immediate environment/‘microsystem’ (e.g., family relationships), personal relationships in the ‘mesosystem’ (e.g., peer and school relationships), external factors in the young person’s local area context/‘exosystem’ (e.g., drug culture and criminality) and wider societal aspects in the ‘macrosystem’ (e.g., mental health policy, health care inequalities and stigma).
In socioeconomically disadvantaged urban areas, social context, specifically the micro-, meso-, exo-, and macro-system impact both on the young person’s experience of mental health or substance use problems and services, which endeavour to address these problems. Interventions that effectively identify and treat these problems should reflect the additional challenges posed by such settings.
Sentinel species are increasingly used by disease managers to detect and monitor the prevalence of zoonotic diseases in wildlife populations. Characterizing home-range movements of sentinel hosts is thus important for developing improved disease surveillance methods, especially in systems where multiple host species co-exist. We studied ranging activity of major hosts of bovine tuberculosis (TB) in an upland habitat of New Zealand: we compared home-range coverage by ferrets (Mustela furo), wild deer (Cervus elaphus), feral pigs (Sus scrofa), brushtail possums (Trichosurus vulpecula) and free-ranging farmed cattle (Bos taurus). We also report in detail the proportional utilization of a seasonal (4-monthly) range area for the latter four species. Possums covered the smallest home range (<30 ha), ferrets covered ∼100 ha, pigs ∼4 km2, deer and cattle both >30 km2. For any given weekly period, cattle, deer and pigs were shown to utilize 37–45% of their estimated 4-month range, while possums utilized 62% during any weekly period and 85% during any monthly period of their estimated 4-month range. We suggest that present means for estimating TB detection kernels, based on long-term range size estimates for possums and sentinel species, probably overstate the true local surveillance coverage per individual.
Semiconductor nanocrystals (i.e., Quantum Dots, QDs) exhibit size-dependent emission properties and have synthetically adjustable ligand shells, making them interesting materials for applications ranging from luminescent displays to biomolecular tags. In this paper, the electrochemical properties of two types of nanocrystal are studied with an emphasis on the effect of core/shell vs core structures. The band gap energy of CdSe particles, measured using optical spectroscopy, was shown to increase slightly with the application of a ZnSe shell, as expected based on the increased energy required to transfer an electron through the shell material. The electrochemically determined band gaps are overestimated in the case of CdSe/ZnSe core/shell nanoparticles, reflecting the band gap of the ZnSe shell. Finally, QDs were self-assembled onto gold surfaces by electrostatic and covalent attachment, and their presence confirmed by fluorescence spectroscopy. The high intensity of emitted light shows that the QDs can be self-assembly onto metallic surfaces, without energy transfer quenching of the luminescence.
Speleological, stratigraphic, paleomagnetic and faunal data is presented for the Buffalo Cave fossil site in the Limpopo Province of South Africa. Speleothems and clastic deposits were sampled for paleomagnetic and mineral magnetic analysis from the northern part of the site, where stratigraphic relationships could be more easily defined and a magnetostratigraphy could therefore be developed for the site. This is also where excavations recovered the fossil material described. A comparison of the east and South African first and last appearance data with the Buffalo Cave fauna was then used to constrain the magnetostratigraphy to produce a more secure age for the site. The magnetostratigraphy showed a change from normal to reversed polarity in the basal speleothems followed by a short normal polarity period in the base of the clastic deposits and a slow change to reversed directions for the remainder of the sequence. The biochronology suggested an optimal age range of between 1.0 Ma and 600,000 yr based on faunal correlation with eastern and southern Africa. A comparison of the magnetobiostratigraphy with the GPTS suggests that the sequence covers the time period from the Olduvai event between 1.95 and 1.78 Ma, through the Jaramillo event at 1.07 Ma to 990,000 yr, until the Bruhnes–Matuyama boundary at 780,000 yr. The faunal-bearing clastic deposits are thus dated between 1.07 Ma and 780,000 yr with the main faunal remains occurring in sediments dated to just after the end of the Jaramillo Event at 990,000 yr.