Dissertations / Theses on the topic 'Koala growth and behaviour'
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1
Logan, Murray. "Nutritional stresses and the feeding behaviour and activity patterns of free-ranging koalas (Phascolarctos cinereus : Goldfuss)." Monash University, School of Biological Sciences, 2003. http://arrow.monash.edu.au/hdl/1959.1/9593.
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Ma, Xun 1952. "Sintering and grain growth behaviour of Si3N4 ceramics." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=56789.
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During sintering, $ rm Si sb3N sb4$ transforms through a liquid phase from the metastable $ alpha$ phase to the stable $ beta$ phase. In this work, $ rm Y sb2O sb3, Al sb2O sb3$ and AlN were added as liquid-forming additives, which react with surface SiO$ sb2$ on the $ rm Si sb3N sb4$ particles. The mechanism of pressureless sintering $ rm Si sb3N sb4$ with these additives was a combination of particle rearrangement, solution-precipitation and elimination of closed porosity. The rate of densification and $ alpha$-$ beta$ phase transformation were strongly influenced by the amount and viscosity of liquid phase. The kinetics suggested that the rate of densification increased with $ rm Al sb2O sb3$ content, since the higher viscosity of the liquid provided more capillary pressure. On the other hand, the rate of transformation was improved by a higher $ rm Y sb2O sb3$ content, because of the increased rate of solution and diffusion in the low viscosity liquid environment. In addition, AlN decreased the rates of both densification and transformation, due to its low solubility in the liquid phase.A morphology analysis was carried out on the samples sintered in the range 1600$ sp circ$C to 1900$ sp circ$C and at 1850$ sp circ$C for various soaking times. The coarsening process of the $ beta$ grains occurred with increasing temperature. Moreover, the $ beta$ grain aspect ratio and size distribution also increased with prolonged sintering. The formation of $ beta$ phase indeed improved the mechanical properties of the materials, however, excessive grain growth led to microcracking, which decreased the strength. The best values were obtained at 1850$ sp circ$C for one hour and corresponded with 98% theoretical density and 100% $ beta$ structure. At higher temperature, the strength decreased, due to decomposition of the $ rm Si sb3N sb4.$
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Howard, Simon William. "Effects of trout on galaxiid growth and antipredator behaviour." Thesis, University of Canterbury. Biological Sciences, 2007. http://hdl.handle.net/10092/1438.
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The introduction of trout has been implicated in the declines in native fish fauna in New Zealand and worldwide. Since the introduction of brown (Salmo trutta) and rainbow (Oncorhynchus mykiss) trout to New Zealand in 1867, their distribution has spread and they have been implicated in the fragmentation of native fish distributions, particularly native non-migratory galaxiids. However, in the Upper Waimakariri basin the co-occurrence of trout and galaxiid populations is relatively common, even in streams where trout reach sizes known to be piscivorous. To investigate mechanisms that may regulate trout and galaxiid co-occurrence, I investigated differences in antipredator behaviour and growth rate between stream types with varying levels of trout presence. Using quantitative survey data collected between 1997 and 2006, I found that trout abundance was low and varied annually in frequently disturbed sites compared their high abundance in stable streams. This finding was used to classify streams into three population types, barrier (trout absent), disturbed (trout presence intermittent) and sympatric (constant trout presence). Using this classification, I tested the effects of trout chemical cues on galaxiid activity and refuge use in artificial channels. There were no differences in activity or refuge use between trout odour and there were no effects of population type or galaxiid size during both the day and the night. Using otolith weight-fish length relationships in galaxiids collected from each population type, I found that galaxiid growth rate was higher in disturbed streams than in stable streams either with or without trout. An experiment manipulating trout size and presence, over two months in a natural stream, found galaxiids from treatments without trout grew slower than those with trout. Slow growth rates in galaxiids above trout-migration barriers and in sympatry, combined with low growth rates in treatments without trout suggest that the mechanisms that regulate galaxiid growth are more complex than previously thought.
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Wang, Fei. "Austenite grain growth behaviour of HSLA steel during reheating treatment." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7415/.
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The grain growth behaviour during reheating between 950 ºC and 1300 ºC of as-cast Al-Nb steel (containing 0.019 wt% Nb and 0.057 wt% Al) and rolled Nb-containing steel (containing 0.028 wt% Nb and 0.031 wt% Al) have been investigated. In particular the role of microalloying element segregation during casting and, hence the spatial distribution of microalloying precipitates, on grain boundary pinning during reheating has been considered. The Al-Nb containing steel has been examined in separate initial conditions, including as-cast (segregated structure), homogenised and forged (reduced separation of segregated bands) samples. It was found that microalloy segregation occurred between the dendritic and interdendritic regions, where the secondary dendrite arm spacing (SDAS) was 150 ± 50 μm. Nb showed strong segregation into the interdendritic regions resulting in a higher number density of Nb(C,N) precipitates (2.64 × 104 /mm2) compared to the dendritic region (0.73 × 104 /mm2). However, Al did not show strong segregation resulting in relatively well-distributed AlN precipitates in the matrix (1.29× 104 /mm2 in the interdendritic region and 1.89× 104 /mm2 in the dendritic region). After forging, the separation between the segregated bands was reduced to 65 ± 10 μm from the previous 150 ± 50 μm in the as-cast sample. The increased Nb content in the rolled Nb-containing steel compared to the Al-Nb steel gave a greater extent of segregation in the solute-enriched regions resulting in a larger number density of Nb(C,N) present (5.9× 104 /mm2), whilst the separation between in the segregated bands in the as-rolled Nb-containing steel was 35 ± 10 μm.
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Whiteman, G. R. "Filamentous and dispersed growth in anaerobic contact systems." Thesis, University of Newcastle Upon Tyne, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354402.
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Shi, Wei. "Growth and Behaviour : Epigenetic and Genetic Factors Involved in Hybrid Dysgenesis." Doctoral thesis, Uppsala universitet, Zoologisk utvecklingsbiologi, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4784.
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In mammals, the most frequently observed hybrid dysgenesis effects are growth disturbances and male sterility. Profound defects in placental development have been described and our work on hybrids in genus Mus has demonstrated putative hybrid dysgenesis effects that lead to defects in lipid homeostasis and maternal behavior. Interestingly, mammalian interspecies hybrids exhibit strong parent-of-origin effects in that offspring of reciprocal matings, even though genetically identical, frequently exhibit reciprocal phenotypes. Recent studies have provided strong link between epigenetic regulation and growth, behavior and placental development. Widespread disruption of genomic imprinting has been described in hybrids between closely related species of the genus Peromyscus. The studies presented in this thesis aim to investigate the effects of disrupted epigenetics states on altered growth, female infanticide and placental dysplasia observed in Mus hybrids. We showed that loss-of-imprinting (LOI) of a paternally expressed gene, Peg1, was correlated with increased body weight of F1 hybrids. Furthermore, we investigated whether LOI of Peg1 in F1 females would interfere with maternal behavior. A subset of F1 females indeed exhibited highly abnormal maternal behavior in that they rapidly attacked and killed the pups. By microarray hybridization, a large number of differentially expressed genes in the infanticidal females as compared to normally behaving females were identified. In addtion to Peg1 LOI, we studied allelic expression of numerous imprinted genes in adult Mus interspecies hybrids. In contrast to the study from Peromyscus, patterns of LOI were not consistent with a direct influence of altered expression levels of imprinted genes on growth. Finally, we investigated the allelic interaction between an X-linked locus and a paternally expressed gene, Peg3, in placental defects in Mus hybrids. This study further strengthened the notion that divergent genetic and epigenetic mechanisms may be involved in hybrid dysgenesis in diverse groups of mammals.
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Murtaza, Ghulam. "Corrosion fatigue short crack growth behaviour in a high strength steel." Thesis, University of Sheffield, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.734606.
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Wang, Chun Hui. "The effect of mean stresses on short fatigue crack growth behaviour." Thesis, University of Sheffield, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364694.
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Gadagkar, Sudhindra R. "Social behaviour and growth rate variation in cultivated tilapia, Oreochromis niloticus." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq24740.pdf.
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Huang, Shuwen. "Molecular genetic epidemiological studies of smoking behaviour and growth promoting genes." Thesis, University of Southampton, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.484852.
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Objectives: 1. Smoking is a major cause of death and often initiates in adolescence. Raploinsufficiency of CYP2A6 in adults is associated with lower cigarette consumption, lower cotinine level and higher quit rates. Other genes are also implicated in smoking behaviour. I explored genotypes of CYP2A6 and other genes in relation to smoking behaviour and cotinine levels in the UK-wide School Heart and Health Study (SHHS). 2. The associations between low birthweight and adult disorders have been widely investigated. Environmental factors have been widely investigated but there has been less focus on genetic factors. There is however evidence that GH-CSH influences adult OR level, one year weight, metabolic syndrome traits and bone loss. I focused on major growth genes in relation to birthweight and other metabolic traits in the SHHS cohort. 3. Results from previous studies led to the hypothesis that some ACE D allele phenotypic associations may represent proxy marking of causal factors located in the GH-CSHgene cluster. I tested this hypothesis for cardiac muscle growth response to exercise and ACE level in a British army heart study cohort. Methods: 1. 1,520 subjects from the SHHS were genotyped for CYP2A6 alleles *lA, *IB, *2, *4, *5, *9 and *12 to classify predicted nicotine metabolism rate. DBB, MAOA, DRD4 and 5HT2A markers were also studied. 2. Microsatellites CSHI.OI and IGFI(CA)n were genotyped and analysed in relation to birthweight and other metabolic traits in the SHHS cohort. 3. Combined analyses ofACEYD and GH-CSHBgl IlB in relation to exercise induced left ventricular mass (LVM) change and serum ACE activity were investigated in a group of Caucasian males in the UK. Linkage disequilibrium (LD) analysis and other genetic statistical analysis were carried out. Results: 1. Those predicted to be half normal metabolisers due to haploinsufficiency ofCYP2A6 (carriers of one fully inactive allele, i.e. *2, *4, or *5) were more likely to be a current smoker at age 18 years. Current versus ever odds ratio was 1.95 (95% C.I. 1.03-3.68). Salivary cotinine levels in current smokers were significantly lower in the 'normal' group compared with 'slow' or 'very slow' group. 2. The CSHI.OI IT genotype in the SHHS boys showed a higher birthweight compared with those DIDI or D2D2 genotype. There was no evidence for association ofthe IGFI(CA)n genotype with birthweight in the SHHS, but boys of 1921192bp genotype did show a leg length 0.65cm greater (p=0.05) than those not homozygous for allele I92bp. 3. A significant association between GH-CSHBgl lIB and ACE activity was detected but only through its LD with ACEYD. No association between GH-CSHBgl lIB and LVM change was found. Conclusions: 1. CYP2A6 haploinsufficiency increases likelihood of continuing smoking in teenagers. 2. My study provides evidence for effects ofGH-CSHon birthweight in males. Complexities ofmy data relative to previous data are discussed. 3. Cardiac muscle growth response to exercise and ACE levels both appear to be attributable to ACE polymorphism and not to nearby GH-CSHpolymorphism, although this does not exclude otherACE attributed phenotypes being due to GH-CSHvariation.
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Cooke, Julie Elaine. "The control of mouse primordial germ cell behaviour by growth factors." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338133.
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McBain, Vikki A. "Small applied electric fields, growth factors and corneal epithelial cell behaviour." Thesis, University of Aberdeen, 1999. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU123848.
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Wounding of the cornea generates lateral electric fields (EFs) and initiates the expression of hepatocyte growth factor (HGF) and keratinocyte growth factor (KGF; Chiang et al., 1992; Wilson et al., 1999a). Therefore, these biologically generated EFs and endogenous growth factors may be of particular significance during wound healing. In the presence of an EF (150 mV/mm) cultured corneal epithelial cells (CECs) oriented perpendicular, directed cathodally and migrated at an enhanced rate. The induction times, induction thresholds and response patterns for these behaviours in increasing field strengths, indicated that they may operate through separate and parallel pathways. The application of either HGF or KGF enhanced the rate of CEC migration but neither affected the extent of CEC orientation or directionality. The distribution of HGF receptors (HGFR) was found to be exclusive to the cell body in the presence of an EF, the receptors accumulated cathodally. Moreover, the asymmetrical accumulation of HGFR in the presence of an EF correlated with the direction of CEC migration. The application of both HGF and an EF activated extracellular-signal regulated kinase (ERK) a mitogen-activated protein kinase. Furthermore, in the presence of an EF the observed ERK activation was greater in the cathodal facing half of the CECs. Inhibition of ERK reduced the extent of HGF and EF-enhanced CEC migration rate but did not alter EF-induced CEC cathodal directionality or perpendicular orientation. The HGF- and EF-enhancement of CEC migration rate may involve the activation of ERK and with the downstream liberation of leukotrienes and phosphorylation of MLCK, would culminate in actin contraction and polymerisation respectively. The potential clinical relevance for this work would concern the topical application of HGF and exogenous application of EFs to corneal epithelial wounds in order to augment healing in patients where this process is slow or deficient.
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Fang, Chizhou. "Influence of oxide growth along grain boundaries on the crack growth behaviour of a nickel-based superalloy." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8518/.
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Stress-assisted grain boundary oxidation (SAGBO) is one potential mechanism accounting for the detrimental effect of oxygen on dwell fatigue crack growth behaviour. This mechanism is assumed to weaken the grain boundaries by formation of oxide intrusion along the grain boundary ahead of the crack tip. In this thesis, finite element analyses of oxide formation along grain boundary ahead of a stationary crack have been carried out to study the stress-assisted oxidation behaviour and the corresponding evolution of stress state near the crack tip during oxide formation. A coupled stress-reaction model was established, of which the mechanical constitutive behaviour was represented by a microstructure-explicit constitutive model and the oxide formation by multicomponent diffusion and thermodynamics. Two microstructures with different particle distribution were involved in the simulations to study the effect of microstructure on the oxide formation. A criterion for oxide fracture was proposed. In combination with finite element simulations, it was used for prediction of crack growth rate during dwell period. The predicted results were in the same order of magnitude as experimental data and indicates a same trend of the influence of microstructure on crack growth rate as what was observed in literature.
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Roberts, Jane Andrea Eileen. "The dynamic behaviour of micro-organisms in continuous culture." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238731.
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Jiang, Bo. "Solidification behaviour of magnesium alloys." Thesis, Brunel University, 2013. http://bura.brunel.ac.uk/handle/2438/8407.
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Magnesium alloys have been extensively used for structural and functional applications due to their low densities. In order to improve the mechanical properties, grain refinement of the microstructures of magnesium alloys has been studied for many years. However, an effective and efficient grain refiner or refinement technique hasn’t been achieved yet, especially for those with aluminium contained. In this study, solution for this problem has been discovered through further understanding of the solidification process, including the potency and the efficiency of nucleation particles, the role of solute, and the role of casting conditions. First of all, the study suggested that MgO particles can act as nuclei in magnesium alloys by measuring and analyzing the differences in cooling curves with various amount of endogenous MgO particles. The differences indicated that the number density of MgO particles has a huge influence on the microstructure. This idea has been fatherly proved by the inoculation of MgO particles in magnesium alloys because the microstructures have been significantly refined after the inoculation. A new kind of refiner (AZ91D-5wt%MgO) has been developed based on such understandings. Secondly, the study discovered that the role of solute has much smaller effect on the grain size than it was suggested in traditional understandings. The inverse-proportional relationship between the grain size and the solute is highly suspected and the major role of solute is to cause columnar- equiaxed transition. The role of casting conditions has also been studied in order to provide experimental evidence for the existence of melt quenching effect in magnesium alloys. It is shown that various casting conditions, such as pouring temperatures and mould temperatures, have large influence on the critical heat balance temperature after rapid pouring. In this study, a theoretical model based on the analysis of cooling curves is presented for grain size prediction. An analytical model of the advance of equiaxed solidification front is developed based on the understanding of the role of casting conditions. Eventually, all these understandings have been applied to magnesium direct-chill (DC) casting. The refined microstructure of DC cast ingots can further assist in understanding the mechanism of advanced shearing achieved by MCAST unit. The comparison of the ingots with and without melt shearing indicated that the advance shearing device can disperse MgO film into individual particles.
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Thompson, L. "The influence of radiation quality on the behaviour of grassland species." Thesis, Bangor University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234470.
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Faitrouni, Taha A. "Effects of structure on the fatigue behaviour of ABS polymers." Thesis, Cranfield University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.237557.
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Varli, Aziz Egemen. "Fatigue Crack Growth Behaviour Of Aa6013 Aluminum Alloy At Different Aging Conditions." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/2/12607440/index.pdf.
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The effect of different aging treatments on fatigue crack growth behavior of AA6013 aluminum alloy was investigated. C(T) (Compact Tension) specimens were prepared in L-T and T-L direction for fatigue crack growth tests. Samples were in T651 as received, T42 which is solution heat treated at 538 ºC for 90 minutes, water quenched and aged in room temperature for 96 hours, and one group of samples were overaged at 245 º
C for 12 hours after T42 condition was achieved. Hardness and conductivity measurements were achieved for all conditions after the heat treatments. Fatigue crack growth tests were performed at as received condition T651, T42 and 245 º
C aged samples in laboratory air with sinusoidal loading of stress ratio R=0.1 and at a frequency of 1 Hz. The highest fatigue crack growth resistance is observed for T651 T-L and 245 º
C overaged L-T condition.
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Dennis, Roger James. "Mechanistic modelling of deformation and void growth behaviour in superalloy single crystals." Thesis, Imperial College London, 2000. http://hdl.handle.net/10044/1/11302.
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In this work the constitutive behaviour and the influence of casting defects on the failure of Ni-base single crystal (SC) superalloy components is investigated. It is well known that the presence of casting-related porosities can lead to the nucleation of microcracks under both creep and fatigue conditions and thus, ultimately produce component failure. A rate dependent crystallographic formulation is introduced to describe the inelastic deformation behaviour of the latest generation of single crystal superalloys. The evolution of the current dislocation and obstacle network is described through appropriate slip resistance and internal or back stress variables for each slip system. Good correlations are obtained between experimental data and numerical predictions within the 750◦C .- 950◦C temperature range and for < 001 > and < 111 > crystallographic orientations. The formulation is then numerically implemented into the FE method and used to investigate the deformation of a representative material volume containing a spherical void of approximately 20 micrometers diameter. The functional dependence of the void growth rates in terms of material anisotropy, stress state, temperature and interaction with a free surface is determined. It is shown that the rate of growth of casting defects in an infinite single crystal medium is strongly dependent on the applied triaxiality and relative orientation between the crystallographic axes and the applied stresses. Furthermore, it has been found that, for the acceleration of the defect growth rate as the result of its proximity to a free-surface to be non-negligible, the void needs to be within two diameters of the free surface. Based on the above results, a framework is proposed to describe the growth of embedded casting defects within superalloy single crystals under a given applied multiaxial stress state. The framework provides an explicit link between the mesoscopic (at the level of the voids) and the macroscopic length scales. A number of blunt notch bar creep specimens and thermo-mechanical cyclic stress-strain specimens were tested to validate both the rate dependent crystallographic formulation and the micro-mechanics void growth model. In addition microstructural analysis of the blunt notch bars provided necessary data for the development of a micro-crack initiation criterion. A life assessment methodology combining these models is developed and applied in the analysis of an actual gas turbine blade. It is expected that the understanding of defect growth kinetics and the corresponding damage accumulation will be beneficial in the design and life prediction of superalloy components.
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Zheng, Junhua. "Characterisation of the fatigue crack growth behaviour of advanced aero-engine alloys." Thesis, University of Portsmouth, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310400.
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Prentice, Garry Raymond. "Assessing undergraduate students' drug attitudes and behaviour change using latent growth modelling." Thesis, University of Ulster, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252415.
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Tsunoda, Katsuhiko. "The role of visco-elasticity on the crack growth behaviour of rubber." Thesis, Queen Mary, University of London, 2001. http://qmro.qmul.ac.uk/xmlui/handle/123456789/28950.
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This thesis concerns crack growth phenomena in rubber. It is widely known that a relationship exists between the magnitude of the stored energy release rate available to drive a crack, called the tearing energy (7'), and the resultant crack growth rate. For rubbers this basic relationship is said to be a characteristic of the material. The magnitude of T is related to both the visco-elastic losses and the crack tip diameter (d) However the actual size of d and its relationship with the viscoelastic losses is not clear. This thesis examines the crack growth behaviour in relation to d and the visco-elastic losses for a wide range of rubbers, whose visco-elastic properties are altered either by swelling in a liquid, altering the test temperature or the cross-link density and by the incorporation of fillers. Static, constant T, crack growth tests were carried out. These revealed that two different crack growth processes exist. For the fast crack growth process, T is determined by variations in the visco-elastic losses alone. For the slow crack growth process, T is determined by variations in both the visco-elastic losses and d. It is proposed here that the factors, which alter d, are associated with cavitation ahead of the crack tip for unfilled materials and with strength anisotropy for carbon black filled materials. In cyclic crack growth tests, the crack growth per cycle, dc/dn, can be considered to result from the sum of time and cyclic dependent crack growth components. For the first time, the detailed magnitudes of the contribution of each of these components to dc/dn have been determined, for a wide range of materials and mechanisms responsible for this behaviour are postulated. Also crack growth tests, both static and cyclic, were extended to very large extensions. Lastly this investigation revealed that the tensile strength for both ciystallising and noncrystallising rubber can be predicted using the tearing energy concept for a variety of loading regimes.
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Upton, Caroline. "Factors controlling root growth in heterogeneous substrates : physical structures and root behaviour." Thesis, Abertay University, 2016. https://rke.abertay.ac.uk/en/studentTheses/f556f1fc-0529-4555-b985-320f853780c6.
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Roots are essential for nutrient uptake and anchorage for the plant, however there is published evidence to suggest that the physical structure of soil has a strong influence on their abilities to grow and develop healthily. Observing roots in 3-dimensions, in situ and non-destructively is important for understanding the complex nature of the physical root/soil relationship, however roots are notoriously difficult to observe due to the opaque nature of soil. This problem can be partially negated by using techniques such as X-ray micro-computed tomography, but is an expensive and time-consuming technique. Furthermore, soil is a growth medium prone to spatial and temporal variation in terms of water, nutrient availability, and microbial populations, making it difficult to observe the effects of soil physical structure alone. The development of transparent soil (TS) by Downie et al. (2012) has brought about a new era in the study of root/soil interactions. TS is a growth medium with the transparency of agar and some of the physical heterogeneity of soil. TS has particles and pores, so roots can explore it in much the same way as they would soil, however the water and nutrient levels can be better controlled and microbial influences are less of an issue, due to the semi-sterile conditions that transparent soil cores are kept under. Downie et al (2012) used TS to study root growth of small Arabidopsis thaliana roots and also imaged Psuedomonas fluorescens colonising lettuce seedling roots. This project scaled the TS system up in order to image larger root systems of Hordeum vulgare (barley) seedlings under different physical conditions. Comparisons of barley roots growing in soil and TS were made, and it was found that roots grew longer in natural soil than in TS. The TS was then sieved into different particle size ranges and it was found that barley roots grew more successfully in the smaller particles (850-1250 μm) than the larger particles (>1676 μm). Vertically stratified split pots, containing large particles down one side and small particles down the other were also used and non-destructively imaged at 24-hour intervals. It was found that the presence of the large particles had an inhibitory effect on root growth across the entire root system, including the roots that were growing in the smaller particles. Finally a device was designed which allowed the application of compression to the TS system. It was found that root growth decreased proportionally with the level of pressure that was applied to the TS cores. Manipulation of TS structure and the development of techniques to quantitatively record root growth and physical soil conditions from 3-D images has enabled us to measure root growth in barley roots under different physical conditions. The results showed that root growth is heavily influenced by particle size, pore structure and soil strength. Root/soil contact was consistently observed as an important soil property for root growth across experiments.
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Appleby, Bradley. "Attitudes toward Urban Living, Landscape, and Growth at the Dawn of Greater Toronto's Growth Management Era." Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/2898.
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The Greater Toronto Area (GTA) is Canada's largest metropolitan area and principal destination for international migration and investment. Over the next 25 years, the GTA is anticipated to grow by approximately 2. 5 million people to a population of almost 8 million. While many view this growth as a symbol of economic prosperity, others see it as a threat to Toronto's economic, environmental and social well-being due to the dispersed, automobile-oriented way in which the city has accommodated its growth since the 1950s. Over the last two decades, planners have focused much energy on ameliorating the shortcomings of post World War II urbanization by developing policy measures such as Smart Growth, Growth Management, and New Urbanism that aim to alter the way in which cities are built and thereby effect change in the lifestyles that have precipitated from this landscape. In Ontario, the Provincial Government recently launched a Growth Management campaign for the Toronto area called Places to Grow. Although many have attempted to define this relationship between environment and behaviour, little attention has been given to attitudes, preferences, and behavioural tendencies of those who will be most directly affected by such policies: the general public.
This study surveys residents from six GTA neighbourhoods in order to understand their attitudes and preferences toward urban living and accommodating urban growth and thereby shed light on where support may be found for implementing Places to Grow. Academic literature suggests that residents generally oppose changes to the physical landscape that do not conform to prevailing cultural values and attitudes. The results of this work indicate that people generally support development that is in keeping with the landscape to which they are habituated. Given that most Torontonians live a suburban lifestyle and that most of Toronto's growth occurs in the suburbs, municipalities may be challenged to implement Places to Grow which stands to impact the suburban landscape more than other areas of the region. If Places to Grow is to be successful, planners must have a better understanding of residents' preferences and motivations in order to attract and maintain their interest in community development throughout the entire planning process.
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Xu, Yigeng. "Closure assessment and overload transient behaviour in damage tolerant airframe materials." Thesis, University of Southampton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390752.
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Servetti, Guido. "Modelling and predicting fatigue crack growth behaviour in weld induced residual stress fields." Thesis, Cranfield University, 2011. http://dspace.lib.cranfield.ac.uk/handle/1826/5617.
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In the last few decades, new design concepts and manufacture processes have
been developed in order to reduce the maintenance and manufacturing costs,
and structural weight of aircraft components. The integral metallic structure
with welding processes is one of the most promising solutions. The exclusion of
fasteners and overlapping joints in the airframe reduces the costs, the weight, and
eliminates stress concentrations near the holes. The research and development
of welding processes for large civil aircraft is in the early stages, thus assessment
of their impact on damage tolerance (DT) design must be carried out before the
technology can be applied for large civil aircraft. Cont/d.
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Sherratt, Jo. "The effect of thermoplastics melt flow behaviour on the dynamics of fire growth." Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/4788.
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The UK Health & Safety Executive are responsible for advising on ways to ensure the safety of employees within the workplace. One of the main areas of concern is the potential problem of unwanted fire, and it has been identified that within the area of large-scale storage in warehouses, there is an uncertainty posed by large quantities of thermoplastic. Some forms of thermoplastic exhibit melt-flow behaviour when heated, and a large vertical array exposed to a fire may melt and ignite forming a pool fire in addition to a wall fire. This project is largely experimental, and aimed at quantifying the effect of a growing pool fire fuelled by a melting wall on overall fire growth rate. The pool fire has been found to increase melting and burning rates, producing a much faster growing fire. It has also been found that - 80% of flowing and burning material will enter a potential pool fire, with only 20 - 25% of total mass loss actually burning from the original array. During the project 400+ small-scale tests and several medium-scale experiments have been undertaken at both Edinburgh University and the HSE's Fire & Explosion Laboratory, Buxton. The experiments have confirmed the main parameters governing pool fire development are molecular weight degradation rate and mechanism, which control flow viscosity. There have also been investigations into other influences, the most significant of which was found to be flooring substrate. These parameters then form the basis of a simple 1-D model. A semi-infinite heat transfer approximation is used to determine temperature profile through a thermoplastic exposed to its own flame flux, with extrapolated temperature dependant material properties. The derived profile is then inserted into a gravity driven flow model, to produce estimates of flow rate and quantity for plastics undergoing either random or end chain scission thermal degradation processes. The model identifies property data which are required to permit its use as a hazard assessment tool.
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Garfield, Alastair S. "Investigating the roles of mouse Grb10 in the regulation of growth and behaviour." Thesis, University of Bath, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442877.
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Thorley, Jack. "The life history of Damaraland mole-rats, Fukomys damarensis : growth, ageing and behaviour." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/284920.
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The social mole-rats have often been typecast as extreme examples of mammalian sociality. With their pronounced reproductive skew, status-related contrasts in lifespan and morphology, and the suggestion of a division of labour amongst helpers, mole-rat societies have repeatedly been likened to the structurally complex societies of some eusocial insects. However, because few studies of mole-rats have quantified individual variation in growth and behaviour across long periods of development, it has remained unclear the extent to which mole-rat societies, and the features of individuals within them, should be considered unique amongst social vertebrates. In this thesis, I examine life history variation in Damaraland mole-rats Fukomys damarensis from three perspectives- growth, behaviour, and ageing- to explore how individual developmental trajectories contribute to, and are influenced by, the structure of mole-rat societies. First, I use a large longitudinal dataset to test for the presence of behavioural specialisation in non-breeding mole-rat helpers. I find no indication of individual specialisation in cooperative activities. Instead, individual differences in helping behaviour are largely the result of age-related changes in the extent to which individuals commit to all forms of helping (Chapter 3); refuting the notion of helper castes. I then focus on the variation in growth across non-breeders, developing a novel biphasic model to accurately quantify sex differences in growth and explore the influence of social effects on growth trajectories (Chapter 4). Despite the proposition of intense intrasexual competition in mole-rat societies, there was no clear signature of sex-specific competition on helper growth trajectories. A more conspicuous form of socially-mediated growth in mole-rats is the secondary growth spurt displayed by females that have acquired the dominant breeding position, causing them to become larger and more elongated. By experimentally controlling reproduction in age-matched siblings, I show that rather than being stimulated by the removal from reproductive suppression, this adaptive morphological divergence is achieved through a lengthening of the lumbar vertebrae when breeding is commenced (Chapter 5). With contrasts in size and shape following the acquisition of the breeding role, this status-related growth pattern shares similarities with growth in naked mole-rats and other social vertebrates. Breeders also show a twofold greater lifespan than non-breeders in Fukomys mole-rats, prompting the suggestion that the transition to dominance also sets individuals onto a slower ageing trajectory. To date, there is little evidence to support a physiological basis to lifespan extension in breeders. This assertion is bolstered by the absence of longer telomeres or slower rates of telomere attrition in breeding females compared to non-breeding females residing in groups (Chapter 6), each of which might be expected if breeders age more slowly. I argue that previous studies exploring status-related ageing in captive Fukomys mole-rats have overlooked the importance of demographic processes (and associated behavioural influences) on mortality schedules. Irrespective of the proximate basis of the longer lifespan of breeders, at an interspecific level the social mole-rats are unusually long-lived for their size. A recent large-scale comparative analysis concluded that prolonged lifespan is a general characteristic of all mammalian cooperative breeders, but this conclusion is premature, as in most of the major clades containing both cooperative and non-cooperative species there is no consistent trend towards lifespan extension in cooperative species (Chapter 7). In the case of mole-rats, it seems more likely that their exceptional longevity arises principally from their subterranean habits and related reductions in extrinsic mortality. Overall, these findings demonstrate that cooperative breeding has important consequences for individual life histories, but there is no strong basis for the claim that Damaraland mole-rat societies are markedly different in form than other cooperative breeding societies.
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Kasese-Hara, Mambwe C. "Feeding behaviour and appetite in young children with non-organic failure to thrive." Thesis, Durham University, 1997. http://etheses.dur.ac.uk/4635/.
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The study reported in this thesis was aimed at investigating taste preferences and caloric compensation in one to two year old children with non-organic failure to thrive (FTT) as compared to normally developing children of the same age. The sample studied included 28 cases with non-organic FTT, and 28 controls with normal growth. The study comprised two experiments. The first tested the child's relative preference for sucrose sweetened solutions versus water. The test session included six 60 second presentations of tastant at three levels of concentration n i.e. water, 0.2 Mol sucrose solution, and 0.4 Mol sucrose solution, with at least 30 second intervals between presentations. The second experiment measured caloric compensation, by testing the child's intake from a standard meal on two occasions, after a pre-load of no-calorie or high-calorie drink. In addition meal time behavioural observations were made, and information about the child’s feeding history was obtained from parent reports. All children regardless of whether they were failing to thrive or not preferred 0.2 Mol sucrose solution to 0.4 Mol sucrose and to water. The energy intake of children with FTT was lower than that of controls, and meal-time behaviours showed some differences between groups in both the child and parent behaviours. Unlike the controls the FTT children showed no caloric compensation, but showed a trend towards the opposite of compensation. Analysis of growth data showed that FTT in the sample studied was present from birth.
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Griffin, David. "Studies of and modelling of the fracture behaviour of composite materials." Thesis, Northumbria University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245214.
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Donahoe, D. M. "The role of differentiation in the genesis of malignancy." Thesis, University of Oxford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234969.
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Harvey, Roy Edward. "The effect of high temperature on yeast fermentations." Thesis, Heriot-Watt University, 1988. http://hdl.handle.net/10399/1000.
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Franks, Antony John. "Heterogeneity in human gliomas : in vitro and in vivo studies of astrocytic neoplasia." Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/18891.
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Li, Weizhong. "A numerical investigation on the behaviour of a rising bubble in a quiescent hot liquid." Thesis, Nottingham Trent University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369237.
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Abhishek, Mishra Swati. "A study of diversification behaviour, growth and market structure of the Indian software industry." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445561.
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Machin, Franklin Qasim. "Development of a system for high throughput screening of agrochemicals affecting plant growth behaviour." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31117.
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Why don’t crop plants grow as fast as they should? In optimal conditions, elite crop varieties routinely outperform those grown in the average field. The vast majority of this reduction in growth activity is due to abiotic stresses such as drought, heat, and nutrient limitation. Abiotic stress reduces plant growth by triggering a reduction of meristem size and causing premature differentiation of proliferating cells. Differentiated cells are no longer able to divide, and smaller meristems have a reduced capacity to restore growth when the abiotic stress passes. We have designed and evaluated a novel high-throughput screening system to identify compounds able to reduce or prevent this premature differentiation in order to retain modest growth capacity in stressful conditions and enable rapid recovery from stress. Such chemicals can be applied to crop plants using existing agricultural methods, and because there is no need for genetic modification, it is widely applicable to many different crop species. Using the novel technique of flow sorting followed by protoplast culture, we have developed a high-throughput automated confocal imaging method to screen chemicals for their effects upon cell differentiation. Meristem protoplasts isolated from the root tips of pROW1:GFP Arabidopsis plants were monitored for differentiation when exposed to different chemicals. To evaluate this system, a library of biologically active small molecules provided by Syngenta was screened against protoplasts and whole plants. Several compounds were identified with the ability to improve Arabidopsis root growth in in vitro growth conditions. Two subsets of these chemicals were identified: a subset of chemicals that improved stress tolerance through modulation of post-meristem differentiation, and a subset of chemicals that improve growth rate by increasing rates of cell division in the root apical meristem. This screening system is able to detect the subset of chemicals that was shown to affect postmeristem differentiation, but not the other subset. No false positives were detected. These results suggest that this single-cell screening system is a powerful, high-throughput method suitable for the detection of molecules for use in crop protection.
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He, Binyan. "Fatigue crack growth behaviour in a shot peened low pressure steam turbine blade material." Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/388077/.
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Enefalk, Åsa. "Fine stream wood : effects on drift and brown trout (Salmo trutta) growth and behaviour." Doctoral thesis, Karlstads universitet, Institutionen för miljö- och livsvetenskaper, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-44537.
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Stream ecosystems and their riparian zones have previously been regarded as two different ecosystems, linked through numerous reciprocal subsidies. Today, ecologists agree that the stream and the riparian zone should be regarded as one system, the stream-riparian ecosystem, which is characterised largely by the subsidies between land and water. The terrestrial subsidies to the stream affect stream-living biota in several ways, some of which are well-known while others less so. The input of wood to the stream from the riparian zone is believed to play an important role in the population dynamics of stream-living fish. In this doctoral thesis, I explore effects of fine stream wood (FW, <10 cm diameter) on wild stream-living young-of-the-year brown trout (Salmo trutta) by reporting and discussing results from laboratory, semi-natural and field experiments. My results show that the local density of drifting prey is higher in the presence of FW than in its absence, and also that young-of-the-year brown trout decrease their diurnal foraging time and prey capture success when FW is added to their habitat. I show that trout decrease their swimming activity in the presence of FW, aggregate in FW bundles, and have lower growth rates than trout without FW access. Also, the degree of sheltering in FW bundles was higher during day than at night in a study performed at low water temperatures; moreover, the presence of an ectothermic nocturnal predator (burbot, Lota lota) did not affect the degree of sheltering in FW bundles by trout. Taken together, my results indicate that young-of-the-year brown trout with access to FW bundles spend considerable amounts of time sheltering in the FW, and by doing so they miss the opportunity for higher growth and foraging rates outside of the shelter. The most probable explanation for this behaviour is that growth is traded off against survival, i.e., the predation risk is higher outside of the shelter.Stream ecosystems and their riparian zones have previously been regarded as two different ecosystems, linked through numerous reciprocal subsidies. Today, ecologists agree that the stream and the riparian zone should be regarded as one system, the stream-riparian ecosystem, which is characterised largely by the subsidies between land and water. In this doctoral thesis, I explore one such subsidy – the input of fine stream wood (FW) to streams. Wild stream-living young-of-the-year brown trout (Salmo trutta) was chosen as study species. My results show that the local density of drifting prey is higher in the presence of FW than in its absence, and that young-of-the-year brown trout decrease their diurnal foraging time and prey capture success when FW is added to their habitat. I show that trout decrease their activity in the presence of FW, aggregate in FW bundles, and have lower growth rates than trout without FW access. Taken together, my results indicate that young-of-the-year brown trout spend considerable amounts of time in FW bundles, and by doing so they miss the opportunity for higher growth and foraging rates outside of the shelter. The most probable explanation for this behaviour is that growth is traded off against survival.
Artikel 3 publicerades i avhandlingen som manuskript med samma titel.
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Arab, Tala Mustapha. "The effect of supplementary light on the behaviour and performance of cattle." Thesis, Bangor University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245311.
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Riou, Samuel. "Regulation of parental effort and chick growth in manx shearwaters : behaviour, physiology and environmental variability." Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511176.
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Gandossi, L. "Crack growth behaviour in austenitic stainless steel components under combined thermal fatigue and creep loading." Thesis, Swansea University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637024.
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This thesis describes the work carried out in an investigation of crack growth behaviour in 316L steel hollow cylindrical components subjected to conditions of thermal fatigue interacting with creep. Type 316L austenitic stainless steel is a widely used material for high-temperature structural components such as heat exchangers. A thorough knowledge of its behaviour in the presence of severe cyclic loading with dwell times at high temperature and under the superimposition of sustained mechanical loads is highly desirable. A review of the relevant literature background, necessary to understand both the fatigue and creep mechanisms in relation to crack initiation and growth, is given. Physical and mechanical properties of the material under examination are then presented. The design and construction of a unique experimental facility able to reproduce the required conditions of creep/thermal fatigue interaction is described. In order to generate the required temperature gradients, induction heating was used to cyclically heat the external surface of thick-walled cylindrical component between 80° and 600°C while the internal surface was cooked by water flow. A mechanical load could be axially introduced in the specimen by means of a dead-weight creep machine. Artificial defects, simulating actual stress concentrators in real components, acted as crack starters. The direct current potential drop method was used for in-situ real-time crack growth monitoring. A significant experimental activity was completed under a combination of varying experimental parameters, such as hold time, severity of the thermal shock and primary load. Numerical methodologies were applied to predict stress fields during cycling and to assess cracking rates. Fracture mechanics crack tip parameters were evaluated. An "effective" stress intensity factor range proved to yield satisfactory results in correlating the experimental data. A general discussion in which the experimental results are analysed is given. Finally, the principal findings are summarised and some areas for future investigation proposed.
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Lee, William (Chun-To). "Harvesting Philosopher's Wool: A Study in the Growth, Structure and Optoelectrical Behaviour of Epitaxial ZnO." Thesis, University of Canterbury. Electrical and Computer Engineering, 2008. http://hdl.handle.net/10092/2507.
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This thesis is about the growth of ZnO thin films for optoelectronic applications. ZnO thin films were grown using plasma assisted molecular beam epitaxy and were studied using various conventional and novel characterisation techniques. The significance of different growth variables on growth efficiency was investigated. The growth rate of ZnO films was found to be linearly dependent on the Zn flux under O-rich growth conditions. Under Zn-rich conditions, the growth rate was dependent on both atomic and molecular oxygen flux. By characterising the oxygen plasma generated using different RF power and aperture plate designs and correlating the results with the growth rates observed, it was found that atomic oxygen was the dominant growth species under all conditions. Molecular oxygen also participated in the growth process, with its importance dependent on the aperture plate design. In addition, an increase in growth temperature was found to monotonically decrease the growth rate. A growth rate of 1.4 Å/s was achieved at a growth temperature of 650 ℃ by using an oxygen flow rate of 1.6 standard cubic centimetres utilising a plasma source with a 276 hole plate operating at 400 W, and a Zn flux 1.4✕10¹⁵ atoms/cm²⋅s. Characterisation of the MBE grown thin films revealed that the qualities of ZnO thin films were dependent on the growth conditions. Experimental evidence suggested that a maximum adatom diffusion rate can be achieved under Zn-rich conditions, giving samples with the best structural quality. O-rich conditions in general led to statistical roughening which resulted in rough and irregular film surfaces. Experimental results also suggested that by increasing the atomic oxygen content and decreasing the ion content of the plasma, the excitonic emission of the ZnO thin films can possibly be improved. It was also found that the conductivity of the films can possibly be reduced by increasing the plasma ion content. By investigating the evolution of the buffer layer surface during the early stages of growth, dislocation nucleation and surface roughening were found to be important strain relief mechanisms in MBE grown ZnO thin films that affected the crystal quality. The usage of LT-buffer layers was found to improve substrate wetting, and was shown to significantly reduce dislocation propagation. Further strain reduction was achieved via the application of a 1 nm MgO buffer layer, and a significant reduction of carrier concentration and improvement in optical quality was subsequently observed. A carrier concentration of <1✕10¹⁶ cm⁻³ and a near band emission full width half maximum of 2 meV was observed for the best sample. The study of electrical characteristics using the variable magnetic field Hall effect confirmed the existence of a degenerate carrier and a bulk carrier in most MBE grown ZnO thin films. The bulk carrier mobility was measured to be ~120 - 150 cm²/Vs for most as-grown samples, comparable to the best reported value. A typical bulk carrier concentration of ~1✕10¹⁶ - 1✕10¹⁸ cm⁻³ was observed for as-grown samples. Annealing was found to increase the mobility of the bulk carrier to ~120 - 225 cm²/Vs and decrease the bulk carrier concentration by two orders of magnitude. Using time resolved photoluminescence, it was found that the radiative recombination in MBE grown ZnO thin films was dominated by excitonic processes, and followed a T³⁄² trend with temperature. A maximum radiative lifetime of 10 ns was observed for as-grown samples. The non-radiative lifetime in ZnO thin films was dominated by the Shockley-Read-Hall recombination processes. The modelling of the temperature dependence of the non-radiative lifetime suggested that an electron trap at ~0.065 eV and a hole trap at ~0.1 eV may be present in these samples. The application of time resolved photoluminescence also allowed the direct observation of carrier freeze-out in these ZnO films at low temperature.
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Laurenson, Gillian. "An investigation into the behaviour and growth of the snail Helix aspersa in artificial environments." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247343.
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Wang, Shiyuan. "Fatigue crack threshold and growth behaviour in a near fully-lamellar gamma based titanium aluminides." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/6347/.
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Fatigue crack threshold (\(D\)K\(_{th}\)) and fatigue crack growth of a near fully-lamellar \(y\)-TiAl alloy (Ti-4522XD alloy) have been investigated in air at room temperature, 400, 650, 700 and 750 oC and at three R ratios (0.1, 0.5 and 0.8). Studies were carried out on both corner-cracked specimens and smooth specimens. A combination of a \(D\)K- increasing loading method and growing a crack from notch were applied throughout the tests. As a consequence of consistent material microstructure, use of standardized testing procedure and a sufficient number of tests, some trends in fatigue threshold and crack growth have been established, including: trends include: lack of dependence of (\(D\)K\(_{th}\)) values on test temperature; average (\(D\)K\(_{th}\)) values decrease with increasing R ratio; a strong dependence of crack growth rate on K\(_{max}\) values at RT; a reduced dependence of crack growth rate on K\(_{max}\) values and increased plasticity at elevated temperatures; crack blunting causes a reduction of fatigue crack growth rate at R=0.8 and at elevated temperatures; and little effect of test temperature on ‘fracture toughness’ values. Above all, the origins of naturally initiated cracks under cyclic loading are often found to be centered on up to four colonies which have failed by interlamellar fracture.
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Li, Shu-Xin. "High temperature creep-fatigue and crack growth behaviour of a single crystal nickel base superalloy." Thesis, University of Bristol, 1993. http://hdl.handle.net/1983/5b2c321c-1c74-450e-be61-a392c419eeb7.
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Taha, Rosna Mat. "Studies on the cellular behaviour of roots of Vicia faba L. in vivo and in vitro." Thesis, Cardiff University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277206.
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Calais, Andreas. "Is personality dependent of growth rate in red junglefowl (Gallus gallus)?" Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-95482.
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Personality has been reported in a large variety of animal species, but it is not obvious why animals have personality. Variation in physiological traits, such as growth rate, should theoretically affect variation in behaviours and thus can explain why we observe variation in personalities. Growth rate is, theoretically, positively correlated with active personality types. Empirical studies have reported this pattern in different fish species, but there are not yet many studies on endothermic animals. I have therefore scored behaviours of 100 red junglefowl (Gallus gallus) chicks in four personality assays; novel arena, novel object, tonic immobility, and a proactive-reactive test, together with recording variation in growth rate of these individuals. The chicks individual growth rate (% day-1) were calculated and the relationship between personality and growth rate investigated. There was significant difference in growth rate between the sexes, where males grew faster than females, detected already at one week of age. However, no significant correlations between behavioural traits and growth rate were observed, indicating that personality seem to be independent of growth rate. Further studies should therefore investigate the generality of this finding, and alternative underlying mechanisms for variation in personality should be explored.
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Solic, Nicola. "A comparative study of the mitogenic and morphogenic effects of epidermal growth factor and amphiregulin on colonic carcinoma cells." Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300825.
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Malleau, Anne Elizabeth. "Effects of a simulated brooding cycle on the behaviour and growth of broiler and layer chicks." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ31850.pdf.
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