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Chemical communication in wild Norway rats (Rattus norvegicus Berkenhout)Landete-Castillejos, Tomás January 1997 (has links)
This study examined the urine and faecal scent marking behaviour and investigatory responses of wild Norway rats (Rattus norvegicus Berkenhout) kept in large, semi-natural enclosures to assess the role these scents play in their communication system. For the first time, this study has shown that Norway rats deposit faecal scent marks in response to odour cues and form latrines. The spatial distribution of faeces was highly uneven. Most faeces deposited in open areas were found in clusters occupying less than 1 m2 which were termed latrines. Rats spent more time at feeders and in other areas which were almost devoid of faeces than at these latrines. This suggests that latrines were created deliberately, perhaps for communication. Rats discriminated among faeces from different donors with respect to their investigation, presumably using olfactory cues. They faecal marked in response to urine cues from rats belonging to other colonies, although they did not faecal mark in response to their own urine cues or to a novel non-social stimulus (clean tiles). Investigation and faecal marking was aimed mainly towards urine from individuals of the marker's own sex. This suggests that faecal marking may play a role in communication between competitors. Urine was deposited as discrete marks around the enclosures, in an uneven distribution. The highest density of marks was found by the enclosure walls and nest areas. Rats showed a greater urine marking response towards introduced clean surfaces than towards surfaces they had already marked, ensuring that their home area was always covered with their urine marks. Close monitoring of urine marking on clean surfaces showed that male -rats had a marking rate three times greater than that of females. This could not be attributed solely to weight differences between males and females. Rats also urine marked in response to urine deposited by rats from other colonies. Urine from unfamiliar rats of the subject's own sex stimulated more investigation than urine from the opposite sex, though donors were immature. These results suggest that urine marking also plays a role in communication between competitors. Testing individuals in their home enclosure, using scent marks deposited naturally by rats, and the contexts in which scent stimuli are deposited by donors (e. g. as part of their home range) and found by residents (e. g. finding intruder's home range marks in the resident's home range) were essential factors in determining their response to olfactory cues. The importance of these factors is discussed.
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Genetic studies of incubation behaviour and Mendelian traits in chickensBasheer, Atia January 2013 (has links)
Finding the genes that underlie variation in production and developmental traits has important economic applications. Incubation behaviour represents a loss of production in conventional breeds of chicken adapted to local conditions and was what motivated this thesis. The Mendelian traits of comb type, crest, Silkie and normal feathers, feathered leg, fibromelanosis, comb colour, skin and shank colour, feather colour and patterns are of interest because of the insight they give to genes and development and were also investigated in the thesis. We used White Leghorn and Silkie lines of chicken to detect the genetic loci controlling incubation behaviour and Mendelian traits using linkage based analysis in an F2 cross. The evidence for QTL affecting incubation status over the whole period on chromosome 5 was strong (P<0.05). After the addition of 218 new informative SNP markers across the genome including chromosome 5 the 95% confidence interval spanned a region around 45 cM having previously been 95 cM. Three other suggestive QTL for incubation status were found after the addition of SNP markers on chromosome 1, 18, 19, E22C19W28 at 70, 0, 1 and 13cM respectively. The mode of action of the incubation status QTL indicates that the White Leghorn allele was either promoting incubation behaviour or that heterozygotes have performance that exceeds the homozygotes except the QTL on chromosome 1 where the Silkie allele is promoting incubation behaviour as might be expected. A highly significant QTL (P<0.01) for early incubation behaviour (25-30 weeks) was found on chromosome 8 at 18 cM. This QTL has an additive effect with the possession of a Silkie allele increasing the likelihood of incubation behaviour. Other suggestive QTL for early incubation behaviour were found on chromosome 26 and 1 at 0 and 66cM respectively. For Mendelian traits, genome wide significant (P<0.01) genetic loci for comb type, crest type and feather type was found on chromosome 7 at 77cM, linkage group E22C19W28 at 7cM and on chromosome 3 at 169cM respectively. Significant genetic loci (P<0.01) for leg colour and skin colour were found on chromosome 20 at 56cM and 60cM respectively. In the present study, loci for all feather patterns were found on E22C19W28 even after removing animals carrying the dominant white alleles, suggesting dominant white or another allele at the locus was still influential. Comb type and incubation behaviour were investigated at the gene level. Thyroid stimulating hormone receptor (TSHR) is believed to be involved in the process of domestication and was found at the peak position of the most significant QTL on chromosome 5 for incubation behaviour. Functional exploration of Wnt genes as a candidate gene for comb type was investigated by in-situ hybridization in Silkie and White Leghorn embryos. The Wnt6 gene showed expression in the region of the presumptive comb development of embryos. In conclusion, for the first time genetic loci that explain maternal behaviour have been described. The coincidence of the incubation behaviour locus on chromosome 5 with the site of the strongest selective sweep in poultry, the TSHR, and the coincidence of QTL on chromosome 1 and 8 with thyroid hormone activity it would appear that the thyrotrophic axis may be critical to the loss of incubation behaviour and improved reproductive performance with domestication. Further analysis of these loci should be able to produce markers that can reduce the propensity for birds to incubate. Comb type marker might allow introgression of this trait to prevent comb damage in commercial hens.
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Capable special school environments for behaviour that challengesLavan, Gary January 2012 (has links)
Numerous interventions have been identified by research as being effective in reducing the severity of some of the core impairments and challenging behaviours of young people with autistic spectrum disorders (ASDs) and learning difficulties. However, the literature cites significant disparity between what is demonstrated to be effective in supporting young people with ASD and challenging behaviour and the support young people and families actually receive in practice. Paper 1 examines the extent to which evidence-based practice translates into actual practice in special schools in the UK for young people with ASD, severe learning difficulties (SLD) and challenging behaviour. A questionnaire survey targeting 64 special schools in the Midlands was used in conjunction with a series of follow-up semi-structured interviews of school staff. The findings indicate that: 1) the ideal of eclectic provision is potentially undermined by a limited range of training received by staff in evidence-based approaches; 2) mechanisms for supporting staff emotional reactions are inconsistently implemented; 3) limited mechanisms exist for developing staff understandings of challenging behaviour. Furthermore, staff attributions regarding challenging behaviour are pivotal to the consistency and effectiveness of any support programme. Implications and future research directions are discussed.
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Analysing the choice of Malaysia as a long-haul tourist destinationMuda, Muhamad January 1992 (has links)
The purpose of this study was to investigate how the British tourists move through a decision process in choosing Malaysia as a long-haul holiday destination. The purchase of a long-haul holiday is thought to be complex with high involvement and deliberation as well as being more expensive and bought less frequently (may be once a year). As such, a five-stage decision process is used: i) problem recognition, ii) information search, iii) evaluation of alternatives, iv) purchase decision and v) postpurchase behaviour. The research was conducted at two levels. The first level was self-administered tourists' survey questionnaire carried-out over a three-month period in Malaysia. The second level involved a British tour operators' survey which was supplemented by personal interview in order to get a better insight into the problems and potentials of Malaysia as a long-haul destination. "In search of new experience," "rest and relaxation",and "cultural attraction" were ranked as the three most important motivational factors influencing the decision to travel long-haul. Personal sources of information seemed to dominate in every stage of the decision process. Tourists evaluated Malaysia very favourably only on two tourist-attracting attributes - entertainment and shopping facilities; but these attributes were less important to them when selecting their holiday destinations. Husbands and wives were found to be in agreement on nine of the eleven subdecisions. Generally, tourists expressed high satisfaction with their holiday experience in Malaysia. Nevertheless some significant differences were found between independent and packaged tourists. Independent tourists were more satisfied with all the "product and service superiority" factors compared to the packaged tourists. With local services, independent tourists were significantly more satisfied than the packaged tourists with pleasant attitudes of the people and the personal security aspects of the "health and safety" factor. With regards to overall value for money and overall satisfaction, the independent tourists were significantly more satisfied than the packaged tourists. Comparison between destinations within the region also revealed different satisfaction levels across various dimensions. The study provides useful empirical support which enable tourism planners in making specific improvements in order to maintain and/or increase tourist satisfaction. For tourism marketers, creation of unrealistic tourist expectation through excessive promotional exaggeration should be avoided to circumvent tourist dissatisfaction.
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The measurement of the deformation properties of Cowden Till at small strainsYung, Peter Chiu Yin January 1988 (has links)
The work described in this thesis was firstly concerned with developing and evaluating automated soil testing equipment and associated instrumentation. The equipment consists principally of a triaxial stress path cell of the Bishop-Wesley type, a microcomputer and two pressure controllers. Inductive displacement transducers have been mounted inside the cell to measure axial and radial strains locally on the specimen boundary and axial strains between the end caps. The local axial strain measurements have proved superior to the end cap measurements which can be adversely affected by bedding errors and misalignment of the transducers relative to the loading axis. Following the development, the system was used to investigate the stress-strain behaviour of Cowden Till, particularly at small strains (0.01 - 0.10%). Cylindrical blocks of 250mm diameter were retrieved from the site and stored under isotropic stress. Eight specimens of 100mm diameter were trimmed from these blocks and subjected to either a drained or undrained compression test under load-controlled conditions. Cowden Till has been shown to exhibit strongly non-linear stress strain behaviour, even at small strains, and most of the shear strain is irreversible. The stress-strain characteristics were in acceptable agreement with those derived from a 865mm diameter plate loading test with under-plate instrumentation. Although the interpretation of the plate test is still being investigated, it is concluded that plate tests provide no better information about the stiffness of the material than triaxial tests of the type described in this thesis. The experimental stress-strain behaviour during compressive loading has been compared with the predictions of some mathematical models. The nonlinear elastic model of Atkinson (1973) appears to be applicable to Cowden Till, for which the behaviour is approximately isotropic. Simple stiffness predictions on the basis of critical state soil mechanics are inadequate at small strains. However, the model of Pender (1978) predicts the behaviour reasonably well. (ii) An attempt has been made to analyse the compression (bedding error) which occurs at the end of a triaxial specimen as the axial strain is increased. A quantification of the compression is hindered by the random nature of surface variations and by the limitations of present theories.
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Intrauterine effects of male mouse fetuses on the adult reproductive physiology of their female siblingsJones, Geraint Vaughan January 1993 (has links)
No description available.
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Heterogeneity in human gliomas : in vitro and in vivo studies of astrocytic neoplasiaFranks, Antony John January 1989 (has links)
No description available.
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The functional analysis of displayPaton, Douglas January 1982 (has links)
No description available.
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The neural control of masculine reproductive and social behaviours in the common marmoset (Callithrix jacchus)Lloyd, S. A. C. January 1989 (has links)
No description available.
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Sexual conflict in the bean weevil, Callosobruchus maculatusCrudgington, Helen Sarah January 2001 (has links)
No description available.
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