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Zhang, Ling. "DOES POPULATION AGEING INFLUENCE ECONOMIC GROWTH?" OpenSIUC, 2019. https://opensiuc.lib.siu.edu/theses/2642.
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Hayward, Christina Elizabeth. "Influence of maternal growth on placental growth, development and function in teenage pregancies." Thesis, University of Manchester, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.516732.
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The UK has the highest incidence of teenage pregnancy in Western Europe, accounting for -7% of all births in England and Wales. Teenagers are more susceptible than adults to delivering small for gestational age (SGA) and growth restricted infants. These infants are at an increased risk of perinatal morbidity and mortality, and chronic health problems in later life. The reasons for teenagers' susceptibility to reduced fetal growth are unknown. Previous studies implicate continued maternal growth as a potential risk factor. In support of this, growing adolescent sheep deliver growth restricted fetuses due to impaired placental growth and nutrient transfer to the fetus. However, a recent prospective observational study (the About Teenage Eating Study; ATE) of 500 pregnant teenagers in the UK demonstrated that maternal growth was not detrimental to fetal growth. One third of teenagers continued to grow during pregnancy and these teenagers delivered fewer SGA (13.1 % vs. 19.5%) and more large for gestational age (10.7% vs. 4.1 %) infants than nongrowing teenagers. The birthweight profile of infants delivered to growing teenagers resembles that in a normal adult population suggesting they can overcome the inherent susceptibility for SGA birth related to young maternal age. My PhD investigated potential placental mechanisms linking maternal and fetal growth, and tested the hypothesis that differences in pregnancy outcome between growing and non-growing teenagers were associated with alterations in placental growth, development and/or function. Placentas were collected from a subset of teenagers recruited to the ATE study. The impact of maternal growth was examined on placental villous morphometry and cell turnover; expression and activity of the amino acid transporter, system A; and maternal- and placental-derived growth factors. The aim was to explore the link between maternal growth factors and placental system A activity. Maternal growth had no major effects on placental weight, morphometry or cell turnover, and thus could not explain the difference in infant birthweight between growing and non-growing teenagers. However, growing teenagers, had higher birthweightplacental weight ratios than non-growing teenagers, suggesting that they have placentas which are more efficient. To determine whether this was due to increased nutrient transport, placental system A activity was assessed. Placental system A activity was lower in teenagers than adults, when comparing those who delivered infants that were appropriately grown for gestational age (AGA). This was consistent with reduced placental mRNA expression of system A transporters, slc38a 1, 2 and 4, in AGA infants delivered to teenagers compared with adults and indicated that placental system A transport, was inherently reduced in teenagers. In contrast, placental system A activity was higher in growing compared to non-growing teenagers, and was equivalent to the levels measured in adults. This could not be explained by changes in mRNA expression of the slc38a genes, indicating up-regulation of system A in growing teenagers at the level of activity. This suggests that growing teenagers were able to overcome inherently reduced placental system A activity. To explore the potential mechanisms, maternal plasma concentrations of insulin-like growth factor (IGF)-I, previously shown to stimulate of system A activity, were compared between growing and non-growing teenagers. Higher concentrations of IGF-I were detected in growing teenagers. However, short term application of IGF-I did not stimulate system A activity in placental villous fragments in vitro. Recent studies suggest that maternal growth is beneficial, rather than detrimental, to fetal growth, and that non-growing teenagers are more susceptible to SGA births. The current study provides evidence of inherently reduced placental nutrient transfer in teenagers, which may contribute to teenagers' susceptibility to SGA births. However, growing teenagers appear able to overcome this susceptibility with increased placental nutrient transport, which may be the result of a maternal hormonal milieu that is conducive to fetal growth. These studies indicate maternal growth primarily impacts placental nutrient transport rather than development. Further studies are required to delineate the underlying mechanisms and identify potential therapeutic strategies to improve pregnancy outcome in the teenage population.
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Zhang, Xunzhong. "Influence of Plant Growth Regulators on Turfgrass Growth, Antioxidant Status, and Drought Tolerance." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30739.
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A series of studies were conducted to examine the antioxidant status, drought and disease tolerance, and growth response to foliar application of soluble seaweed (Ascophyllum nodosum) extracts (SE) and humic acid (HA; 25% active HA or 2.9% active HA) in tall fescue (Festuca arundinacea Schreb), Kentucky bluegrass (Poa pratensis L.) and creeping bentgrass (Agrostis palusttis Huds.) grown under low (-0.5 MPa) and high (-0.03 MPa) soil moisture environments.
Foliar application of humic acid (2.9 % active HA) at 23.7 and 47.4 l/ha improved leaf water status, shoot and root development in tall fescue, Kentucky bluegrass and creeping bentgrass grown under drought. Humic acid (2.9% active HA) at 15.5 l/ha or SE at 326 g/ha significantly reduced dollarspot incidence and improved turf quality in creeping bentgrass.
Drought stress induced an increase of antioxidants alpha-tocopherol and ascorbic acid concentrations in the three turfgrass species. In the experiment with Kentucky bluegrass, drought stress increased beta-carotene concentration, but did not significantly influence superoxide dismutase (SOD) activity.
Foliar application of humic acid (25% active HA) at 5 l/ha and/or SE at 326 g/ha consistently enhanced alpha-tocopherol and ascorbic acid concentrations, leaf water status, and growth in the three cool-season turfgrass species grown under low and high soil moisture environments. In the experiment with Kentucky bluegrass, application of HA at 5 l/ha plus SE at 326 g/ha also increased beta-carotene content and SOD activity under low and high soil moisture environments. There were close positive correlations between the antioxidant status and shoot or root growth in the three turfgrass species regardless of soil moisture levels.
The antioxidant SOD activity, photosynthetic capacity in terms of Fvm690, and chlorophyll content in terms of Fm730/Fm690 exhibited a seasonal fluctuation in endophyte [Neotiphodium coenophialum (Morgan Jones and Gams) Glenn, Bacon, Price and Hanlin] -free and endophyte-infected tall fescue. Application of SE enhanced SOD activity, photosynthetic capacity, and chlorophyll content in tall fescue, especially at 4 weeks after SE treatment. The SOD activity, photosynthetic capacity and chlorophyll content were not significantly influenced by the endophyte infection. A close positive correlation between SOD and photosynthetic capacity during the summer was found in endophyte-free and endophyte-infected tall fescue.<br>Ph. D.
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Murray, Dianne Hamilton. "Influence of growth rate on the immature skeleton." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/25009.
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To investigate how bone architecture is modulated by growth rate, morphometric, biochemical and genetic comparisons were made between tibiae from broiler chickens with either fast or slow growth potentials. Both strains of chickens were kept under identical conditions, and fed ad-libitum standard broiler feed. Tibiae were removed and tested by three-point bending to determine stiffness and breaking strength and cross sections of the tibia were examined histomorphologically. Bone stiffness and breaking strength were higher in the rapidly growing birds, but after adjustment for body weight the bones were inherently weaker. Cortical porosity periosteally, but not endosteally, was increased. Sections reacted for ALP and TRAP activity, and others stained for cement (reversal) lines indicated the absence of primary osteon remodelling in the periosteal region. This suggests that the increased periosteal porosity is due to slower infilling of the primary osteons in the rapidly growing birds. To directly quantify the rate of osteon infilling, tibiae were removed from 21-day-old chicks, which had been double labelled with calcein (80 and 8 h before death). The mineral apposition rate was higher in the slow growing chickens, and confirmed the previous histomorphometry results. Osteocyte density within the circumferential lamellae of the cortical bone was higher in the rapidly growing birds but unchanged within the newly laid down bone of the primary osteons. Immunohistochemical staining of cortical bone sections from chickens injected with bromodeoxyuridine located proliferating pre-osteoblast cells to the osteogenic layer of the periosteum. A lower labelling index in the rapidly growing birds was seen across four circumferential areas of the periosteum (anterior = fast growing area, posterior = slow growing area, medial and lateral = intermediate growing areas), even though the osteogenic layer of the periosteum was thicker in the fast strain. Blood vessel numbers within the periosteum was similar between strains but differed between regions habitually loaded in tension (anterior) or in compression (posterior).
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Deaton, Brady J. "The influence of communications infrastructure on agricultural growth." Thesis, Virginia Tech, 1993. http://hdl.handle.net/10919/46149.
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Lott, Whitney Meghan. "Influence of Growth Factors on Bovine Embryo Development." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/34481.
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Many attempts have been made to improve the in vitro production of cattle embryos by refining in vitro maturation (IVM) and culture systems. Cysteine supplementation to IVM media of bovine oocytes increases cellular glutathione production, which reduces reactive oxygen species (ROS). Similarly, beneficial effects of growth factors for improving the rate of blastocyst development have been reported, but combined effects are unknown. This study was conducted to determine the additive effect of the antioxidant cysteine with epidermal growth factor (EGF) and/or insulin-like growth factor-I (IGF-I) on subsequent embryo development. Bovine oocytes from slaughterhouse ovaries were matured in TCM-199 (control), with or without the addition of 0.6 mM cysteine (C) at 0 or 12 h of maturation. After in vitro fertilization, embryos were allocated to culture treatments containing synthetic oviductal fluid medium. Culture treatments included fetal calf serum (FCS, 4%) alone; IGF-I (100 ng/mL); EGF (10 ng/mL); and IGF-I+EGF (100 ng/mL+10 ng/mL) for all IVM treatments. Although rates for blastocysts development were not different among treatments, an increased proportion of embryos attaining morula formation was achieved when cysteine was added to the IVM media (12 h C IGF-I+EGF, 41.4%; 0 h C EGF, 40.0%) as compared to control (FCS: 34.6%). When cysteine treatments were combined, percent cleavage was greater for IGF-I+EGF (70.8%) compared to FCS (61.2%). The abundance of mRNA from the apoptotic genes, Bax and Bcl-2, and the oxidative stress genes, copper (Cu)-zinc (Zn) superoxide dismutase (SOD; SOD1) and manganese (Mn) SOD (SOD2) in embryos was assessed. No significant treatment effect was observed on the expression of apoptotic and oxidative stress genes. Bax was expressed strongly (4-fold) in morulae with the addition of IGF-I, but was less prevalent in all other morula and blastocyst groups relative to FCS. There was slightly less expression of both SOD1 and SOD2 with treatments compared to FCS in morulae and blastocysts, indicative of low mitochondrial activity and/or a low level of oxidative stress in treatments. There was no significant treatment effect on total cell number, apoptotic nuclei, or apoptotic index. In conclusion, supplementation of cysteine during IVM of oocytes, in conjunction with growth factors could effectively be used as a replacement for FCS.<br>Master of Science
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Rouse, H. "Retinotectal projections influence optic tectum growth in zebrafish." Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1466628/.
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In the zebrafish visual system, the retina and optic tectum grow in register throughout life. Both regions add new neurons from proliferation zones at their margins, with newly differentiated retinal ganglion cells projecting to, and making new synapses in the tectum. Retinal ganglion cell axon innervation appears to regulate size of the target tissue, because the contralateral tectum is reduced in size when an eye is removed. The mechanisms by which the retina affects cell proliferation and/or survival in the optic tectum remain to be elucidated. In this thesis I use the atoh7 mutant, lakritz, and unilateral eye enucleations to investigate the effect of lack of retinal input on growth of the optic tectum. Without retinal ganglion cell innervation, tectal cell proliferation and survival is reduced, yet proliferating cells in non-innervated tectal lobes still migrate away from the germinal margins and differentiate as occurs in innervated tecta. A candidate approach of innervated versus non-innervated brains suggests that retinal ganglion cell axons activate axin2 expression in the tectum. In addition, a novel transgenic approach to silence retinal ganglion cell activity was designed to test the effect of neuronal activity from retinal ganglion cell axons but, as yet, has failed to provide conclusive results. Together, these results show that retinal afferents into the optic tectum regulate tectal cell proliferation and survival.
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Deaton, Brady James. "The influence of communications infrastructure on agricultural growth /." This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-12052009-020226/.
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Powell, Shelly Evans. "Commitment in Marriage: An Influence for Moral Growth." BYU ScholarsArchive, 2009. https://scholarsarchive.byu.edu/etd/2225.
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Marriage continues to be one of the most important relationships to today's Americans (Fowers, 2000), generating numerous studies on the physical, emotional, mental and financial outcomes of marriage (Waite & Gallagher, 2000). Yet, little research has been done to explore the moral outcomes of marriage. Examining how marriage may contribute to individual spouses' moral development is compatible with recent studies on marital virtues that aim to provide a more complete as well as less individualistic view of marriage (Hawkins, Fowers, Carroll, & Yang, 2007). This study adopts a moral personality approach to examine marriage's role in adult moral development. Taking a moral personality approach when studying marriage's influence allows for a broader understanding of moral development that includes character virtues and identity constructs. In order to examine how marriage may exert such a moral influence, it is necessary to focus on aspects of marriage that are characteristically different from those of other relationships. Commitment is one aspect of marriage thought to set it apart as distinct from other relationships (Adams & Jones, 1997). This study examines how commitment may play a role in the moral development of individual spouses themselves. The purpose of the present study was to examine, using qualitative methods, how married individuals experience commitment and how that commitment may be associated with a greater motivation to be moral. Couples were interviewed on how they experience commitment in their marriages. Interviews were recorded, transcribed and analyzed using grounded theory methods. Themes that emerged were organized into the following seven categories: (1) What marriage means; (2) What commitment in marriage means; (3) Examples of the influence of marriage; (4) Moral traits and the influence of spouses; (5) Themes relating to identity; (6) Commitment, challenges, and personal growth; and (7) Other influences on moral development. Themes are discussed in terms of their relation to past literature and how they might be integrated into a conceptual model. Implications for practitioners and suggestions for future research are given.
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Dzotefe, S. A. "Influences on small firm growth rates in Ghana : factors which influence small firm growth rates and which are important in distinguishing rapid-growth small firms from slow-growth small firms." Thesis, University of Bradford, 2008. http://hdl.handle.net/10454/4457.
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Although the development of small businesses is generally considered important for income generation and job creation, there has been relatively little research in developing countries such as Ghana on understanding why some small firms succeed and grow rapidly while others do not in. This thesis investigates the influences on small firm growth rates in Ghana using data from a random sample of 252 manufacturing and services firms from the database of the Association of Ghana Industries. The general hypothesis is that, growth is a function of the characteristics of the entrepreneur; characteristics of the firm; strategic factors; environmental factors; and cultural factors. Consequently, the research tests 36 hypotheses drawn from the five main categories of variables using the turnover and the employment growth measures. It also uses logistic regression analysis to isolate significant factors differentiating rapid-growth firms from slow-growth firms. Overall, the research finds strong evidence which suggests that, perception of a market opportunity; university education; multiple founders; entrepreneurs with marketing skills; workforce training; new product development; presence of a clear vision and mission statement; majority non-family members in management and membership of professional or business associations were associated with rapid-growth firms. iv Factors which were significant in discriminating between rapid-growth and slow-growth firms but were more likely to be associated with slow-growth firms included threat of unemployment or actual unemployment as a motivation for starting a business; production skills; legal form (limited liability companies); access to external equity (post-formation); exporting; access to public or external aid; unionization and frequent management meetings.
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Mainda, Mofya, and Philip Wernstedt. "Influence of loading on bone growth at the growth plates in immature rat metatarsals." Thesis, KTH, Mekanik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-233542.
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Growth of different bones in children is facilitated by different mechanisms according to the anatomical site and function of the bone. Longitudinal bone formation in long and short bones occurs in the cartilaginous growth plates located at each end of the growing bone through a process known as endochondral ossification. This growth continues until a child becomes full-grown at which point the growth plate calcifies to solid bone [1]. It is still unclear how mechanical and biological factors affect bone growth. For the purpose of this study, immature rat metatarsals have been subjected to varying number of cycles (1, 5, 10 and 50 cycles) in order to better understand the effect that mechanical loading has on bone growth. This has been done using two consecutive trials. The trends in these trials were analyzed and compared. Specimens subjected to 5 cycles exhibited the most prominent effect of loading over the course of 16 days. The results of the trials reveal that immature bones are sensitive to cyclic compressive loading. The results revealed a potential threshold below which the loading resulted in an increased growth. Furthermore, simulations of longitudinal bone growth using a thermal-structural coupled analysis, with the findings from the experiment, has been performed. The model results in a stress free structure that is comparable to the growth of the experiments to a certain extent. The model also allowed incorporation of the bent growth that is observed in the experiments.
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Longlands, Sarah L. J. "The Growth Prerogative : how does an objective of economic growth influence local planning policy?" Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7327/.
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This research aimed to explore the privileging of growth and its influence on planning in England. The research examined two contrasting case studies: Middlesbrough Borough Council and Cambridge City Council. The analysis of growth privileging is rooted within a constructionist ontology which argues that planning is about the way in which people construct value relative to the function of land. This perspective enables the research to position growth privileging as a social construction; a particular mental frame for understanding and analyzing place based challenges and an approach which has been increasingly absorbed by the UK planning community. Through interviews with a range of planning actors, the first part of the research examined the state of planning in the current political and economic context and the influence that a privileging of growth has on planning. The second part of the research investigated the merits and feasibility of the capabilities approach as an alternative mental frame for planning, an approach developed through the work of Amartya Sen and Martha Nussbaum. The research results disaggregate the concept of economic growth, based on the responses of interviewees and conclude that it is characterized by homogeneity. Growth is valued, not only because of its economic role, for example, supporting jobs and income but its potential in creating diversity, enriching culture and precipitating transformative change. Pursuing growth as an objective has a range of influences upon planning. In particular, it supports a utilitarian framework for decision-making which values spatial decisions on their ability to support aggregate economic growth. The research demonstrates the feasibility and merits of the capabilities approach as a means with which to better understand the relationship between planning and human flourishing. Based on this analysis, the research proposes that the capabilities approach can provide an alternative ‘mental frame’ for planning which privileges human flourishing as the primary objective or ‘final end’ instead of economic growth.
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Woolford, Timothy James. "The influence of growth factors on neuromuscular junction regeneration." Thesis, University of Leicester, 1997. http://hdl.handle.net/2381/29403.
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Peripheral motor nerve injury frequently results in significant morbidity even after repair employing micro-surgical techniques. Following such an injury the trophic effect of the motor nerve is lost, leading to degeneration of the neuromuscular junction, muscle atrophy and eventually irreversible muscle fibrosis.;Several neurotrophic growth factors (including insulin-like growth factor-I and fibroblast growth factor-I) have been identified. These have been shown to facilitate regeneration of peripheral nerve in-vivo, however less is known regarding any trophic action at the neuromuscular junction.;In this series of experiments the ability of insulin-like growth factor-I and fibroblast growth factor-I to facilitate neuromuscular junction regeneration in atrophic muscle was studied. The growth factors were delivered to the nerve/muscle interface of a nerve implant either as a bolus dose using a fibrin glue carrier or by continuous infusion with a mini-osmotic pump. The animal model employed was the rat lower limb model. Functional testing of the regenerated neuromuscular junctions was performed by measuring muscle twitch force following nerve implantation.;Both growth factors were shown to facilitate neuromuscular junction regeneration in atrophic muscle equally effectively. Despite histological evidence of neuromuscular junction regeneration, functional testing did not demonstrate any significant difference between growth factor treatment groups and controls.
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LaRue, James Edward. "The Influence of Residual Stress on Fatigue Crack Growth." MSSTATE, 2005. http://sun.library.msstate.edu/ETD-db/theses/available/etd-04072005-095303/.
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This thesis discusses the analysis of fatigue crack growth in the presence of residual stresses to determine a suitable method for fatigue life predictions. In the research discussed herein, the prediction methodologies are compared to determine the most accurate prediction technique. Finite element analysis results are presented as well as laboratory test data. The validity of each methodology is addressed and future work is proposed.
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Conley, Travis B. "Growth response to resistance exercise : influence of exercise device." Virtual Press, 2008. http://liblink.bsu.edu/uhtbin/catkey/1395457.
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The purpose of this study was to compare the growth response elicited by an acute bout of resistance exercise (RE) conducted on a traditional weight stack device (WS) and a flywheel device (FW). Eight recreationally trained males (25 ± 9 y, 77 ± 27 kg) performed 4 sets of 7 repetitions of bilateral knee extension on each exercise device separated by 7 days. Muscle biopsies were obtained from the vastus lateralis at rest and 4 hrs post-exercise to examine the expression of selected myogenic and proteolytic genes. RE increased (P < 0.05) mRNA expression of Myogenin (3.6 vs. 3.6 fold), and MyoD (2.2 vs. 2.0 fold) and decreased (P < 0.05) expression of Myostatin (1.4 vs. 1.5 fold) to a similar degree on both exercise devices. There was no change in the expression of Atrogin-1, MuRF-1 or MRF4 following RE on either device. The only device mediated difference in the expression of the selected genes was observed in Atrogin-1 which was lower following RE on the FW versus the WS device. The current data shows that in the initial hrs following RE, use of the FW is as effective as the traditional resistance training devices (WS) in promoting the induction of genes involved with muscle remodeling and growth.<br>School of Physical Education, Sport, and Exercise Science
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Umeda, K., and C. Fredman. "Admire® Insecticide Use and Influence on Cantaloupe Growth." College of Agriculture, University of Arizona (Tucson, AZ), 1995. http://hdl.handle.net/10150/221493.
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Cantaloupe growth was influenced by using imidacloprid (Admire®) insecticide to control, suppress, or reduce whiteflies. The growth rate of cantaloupe was evaluated at regular intervals after crop emergence and a rate response was observed with greater growth with respect to increase in Admire® rate. Following at planting time applications, at 3 and 4 weeks after treatment (WAT) cantaloupe plants had more foliar growth and a greater number of leaves with increasing Admire® rate. At 5 to 8 WAT, cantaloupe vines exhibited greater growth with increasing rates of Admire®.
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Briukhanov, Maksym Vitaliiovych, Максим Витальевич Брюханов, Максим Віталійович Брюханов, and S. A. Zagorulko. "Influence of individual characteristics of president the GDP growth." Thesis, Видавництво СумДУ, 2010. http://essuir.sumdu.edu.ua/handle/123456789/4020.
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Rovinelli, Andrea. "Influence of microstructure variability on short crack growth behavior." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/5794/.
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Fatigue life in metals is predicted utilizing regression analysis of large sets of experimental data, thus representing the material’s macroscopic response.
Furthermore, a high variability in the short crack growth (SCG) rate has been observed in polycrystalline materials, in which the evolution and distributionof local plasticity is strongly influenced by the microstructure features. The
present work serves to (a) identify the relationship between the crack driving force based on the local microstructure in the proximity of the crack-tip and (b) defines the correlation between scatter observed in the SCG rates to variability in the microstructure. A crystal plasticity model based on the fast Fourier transform formulation of the elasto-viscoplastic problem (CP-EVP-FFT) is used, since the ability to account for the both elastic and plastic regime is critical in fatigue. Fatigue is governed by slip irreversibility, resulting in crack growth, which starts to occur during local elasto-plastic transition. To investigate
the effects of microstructure variability on the SCG rate, sets of different microstructure realizations are constructed, in which cracks of different length
are introduced to mimic quasi-static SCG in engineering alloys. From these results, the behavior of the characteristic variables of different length scale are
analyzed: (i) Von Mises stress fields (ii) resolved shear stress/strain in the pertinent slip systems, and (iii) slip accumulation/irreversibilities. Through fatigue indicator parameters (FIP), scatter within the SCG rates is related to
variability in the microstructural features; the results demonstrate that this relationship between microstructure variability and uncertainty in fatigue behavior
is critical for accurate fatigue life prediction.
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Abreu, F. M. S. G. "Influence of atmospheric saturation deficit on early growth of groundnut." Thesis, University of Nottingham, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378471.
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Al, Kholaifi Abdullah. "The induction of liver growth by peroxisome proliferators." Thesis, University of Nottingham, 2008. http://eprints.nottingham.ac.uk/10443/.
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Peroxisome Proliferators (PPs) are a class of chemicals that cause a programme of augmentative liver growth, however, the mechanism which regulates the induction of hepatic DNA synthesis as a result of exposure to peroxisome proliferators is currently uncharacterized. This study sets out to characterise the induction of DNA synthesis in mouse by peroxisome proliferators, as a prerequisite for investigating and identifying the genes that are responsible for induction of DNA synthesis to control liver growth. Administration of BrdU in drinking water can reduce mouse body weight; an optimized protocol was devised, which does not lead to body weight loss, and which enables reliable measurement of DNA synthesis. Male 129S4/SvJae mice were treated with a single dose of ciprofibrate (100-400 mg kg-1) or methylclofenapate (25 mg kg-1) for two days. Although liver to body weight ratios increased significantly at all doses, no induction in DNA synthesis was observed within 2 days. Subsequent time course studies with ciprofibrate (100 mg kg-1day-1) or methylclofenapate (25 mg kg-1day-1) showed that liver-to-body weight ratio was significantly increased in treated groups by day 2, but that the induction of DNA synthesis was increased significantly only after three days of treatment, for both compounds. No induction of hepatic DNA synthesis was observed in PPARa null mice after treatment with ciprofibrate (100mg kg-1day-1) for 2 or 6 days, showing that the effect required the PPARa. A dose-response study with 0,1,3,10,30,100 or 200 mg kg-1 day-1 ciprofibrate for 3 days, or with 0,10,30,100 mg kg-1 day-1 ciprofibrate for 4 days revealed that liver to body weight ratios were significantly increased in 129S4/SvJae mice treated with 10mg kg-1day-1 and greater ciprofibrate at 3 and 4 days, whereas hepatic labelling index was significantly increased at 100 mg kg-1 day-1 ciprofibrate at 3 days after dosing, with progressive increases at doses of 30 and 100 mg kg-1 day-1 ciprofibrate at 4 days after dosing. In order to explain the early time course of induction of DNA synthesis reported by Styles [113] [164] in Alderley Park mice, a time course study was performed between 1-4 days in Alderley park mice using methylclofenapate (25mg kg-1day-1). The study showed that liver growth was induced by day 2, but DNA synthesis was significantly induced only after 3 days of dosing. To evaluate species differences, the time-course of induction of DNA synthesis was examined in F-344 rats treated with ciprofibrate (50mg kg-1day-1) for 1-4 days. The liver-to-body weight ratio was significantly increased in all time points, but DNA synthesis was significantly increased after 2 days of dosing. These findings demonstrate that there was a delay in induction of DNA synthesis by peroxisome proliferators in mouse by at least 48 hours. This delay in response is not due to strain differences. Moreover, induction of DNA synthesis in rat was earlier than those in mouse, which makes rats a feasible experimental model to study the immediate early genes/ proteins induced by peroxisome proliferators to induce liver growth.
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Lacasse, Pierre. "Influence of plane of nutrition, growth hormone and growth factors on mammary gland development and function." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41650.
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Dairy heifers were submitted to high or moderate plane of nutrition before and during first gestation. High plane of nutrition did not increase milk production but negatively affected reproduction and health. In addition, high plane of nutrition decreased growth hormone (GH) concentration and increased prolactin concentration during gestation. There was no effect of previous plane of nutrition on peripartum concentrations of hormones. Milk production was positively correlated with GH concentrations, but was negatively correlated to concentrations of insulin-like growth factor-1(IGF-1) concentrations postpartum.<br>The effect of GH administration on mammary vasculature and on paracrine secretion of growth factors was investigated in lactating and non-lactating dairy cows. The injection of GH induced a linear increase of IGF-1 concentration in blood and mammary primary lymph, but did not affect concentrations of prostaglandin E$ sb2$ (PGE$ sb2$) concentrations. However, the rate of IGF-1 increase was slower in lymph than in blood, suggesting that blood is the source of most lymph IGF-I. Therefore, GH did not seem to affect paracrine secretion of IGF-1 and PGE$ sb2$ by the bovine mammary gland. Growth hormone administration induced a gradual increase in mammary blood flow in lactating cows while it remained constant in non-lactating animals. Changes in lymphatic, but not blood, concentrations of a stable metabolite of the vasodilatator prostacyclin I$ sb2$ parallelled the changes in blood flow. This indicates that local secretion of this vasodilatator may be responsible for the effect of GH on mammary blood flow.<br>Mitogenic activity of mammary primary lymph samples taken at different physiological stages was evaluated on mammary epithelial and mammary fibroblast cell lines. The results indicate that the mitogenic activity of lymph in epithelial cells was not related to physiological stage but to PGE$ sb2$ concentration. In fibroblasts, mitogenic activity of lymph was not related to physiological stage or to the content in any of the growth factors assayed.
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Mackinlay, Gavin Zellweger. "Growing Pains: An Analysis of High Growth Companies and the Attributes that Influence Their Continued Growth." Scholarship @ Claremont, 2016. http://scholarship.claremont.edu/cmc_theses/1505.
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Nearly every company executive strives to achieve rapid growth and expansion for their firm, and does so in an almost single-minded manner. This paper focuses on the seldom discussed or accounted for negative side of rapid growth, namely the growing pains experienced by companies as their larger size creates a variety of challenges, such as increased bureaucracy, financial management, and maintaining efficiency. Specifically, this paper began with the Forbes 100 Fastest-Growing Corporations in 2011 and created a dataset of their corporate information over the five-year period after their recognition (2011-2015). The dataset was analyzed in order to identify the negative factors that those companies experienced due to their rapid growth. The goal of this was provide a roadmap for expansion-minded companies to strategize about their future growth.
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Day, A. D., and M. J. Ottman. "Growth Cycle, Fertilizer, Planting Rate, and Genotype Influence Barley Hay or Forage Growth in the Southwest." College of Agriculture, University of Arizona (Tucson, AZ), 1985. http://hdl.handle.net/10150/200506.
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Luo, Wang-Juan. "Influence of seed and foliar applications of growth regulators on turfgrasses." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-03172010-020308/.
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Wagner, Corey Edward. "Influence of selection for improved growth rate on pork quality." [Ames, Iowa : Iowa State University], 2007.
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Ngiam, Shi Song. "The influence of surface residual stress on fatigue crack growth." Thesis, University College London (University of London), 2007. http://discovery.ucl.ac.uk/1444870/.
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Residual stress exists in most structures and although it has been recognised for a long time, its complex mechanism and characteristics are still being intensively studied. Residual stress can be stratified into damaging residual stress and beneficial residual stress. Surface tensile residual stresses are generally known to reduce the mechanical properties of materials while compressive residual stresses improve the fatigue performance of components. This Ph.D. thesis reports the analytical and experimental work conducted to investigate both the damaging and beneficial effects of residual stress on fatigue crack growth in structural components. The detrimental effect of tensile residual stresses is studied through large scale fatigue testing of T-butt welded plates fabricated from High Strength Steels (HSS). Despite the growing use of HSSs in the offshore industry, the fatigue performance and corrosion resistance of welded joints made from such steels are still not clear. Due to their complex metallurgy and relatively poor weldability, there is still a lack of understanding of the residual stresses that arise from the welding process. This study involved modification and development conducted on a variable amplitude (VA) load-time sequence generator for the investigation of long life fatigue performance of HSS. Emphasis was given to the generation of a stationary load-time history and numerous analyses were presented to demonstrate the importance of the long term statistical nature of the load-time sequence on fatigue testing. Fatigue test results obtained were extensively compared with previous HSS corrosion fatigue studies. The effect of tensile residual stress on fatigue crack growth was investigated using a SIF weight function-based fatigue crack growth model. Two newly developed preferential cold working techniques termed stitch cold rolling and stitch shot peening were explored to investigate the beneficial effect of surface compressive residual stress on fatigue crack growth in mild steel plates. One of the main objectives of this study was to control the fatigue crack shape by the manipulation of surface residual stress fields. The stitch cold rolling technique was implemented using a custom-built cold rolling jig. The feasibility of preferential cold working techniques was further investigated by the fatigue testing of stitch shot peened specimens. Both experimental programmes yielded unprecedented fatigue crack growth results. A residual stress monitoring programme was conducted to study the residual stress relaxation behaviour under cyclic loading. The experimental test results enabled the investigation of SIF solutions in non-uniform stress fields. A novel fatigue crack growth evolution model, which takes into account residual stress relaxation effects, was developed using the powerful SIF weight function methods.
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Wilson, Ronee Elisha. "Influence of Maternal Thyroid Dysfunction on Infant Growth and Development." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4964.
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Thyroid dysfunction is one of the most common endocrine disorders in women of childbearing age and the obstetric consequences of abnormal thyroid hormone levels during pregnancy have been established. Less understood is the implication of the presence of maternal thyroid autoantibodies on infant outcomes among women who are euthyroid during pregnancy. The objective of this study was two-fold: 1) to examine the influence of antenatal thyroperioxidase (TPO) status on fetal/infant brain and body growth measurements at delivery and 2) to explore the relationship of antenatal TPO status and maternal postpartum thyroid dysfunction (PPTD) on early infant growth and neurocognitive development. Six-hundred thirty-one (631) euthyroid pregnant women were recruited from prenatal clinics in Tampa Bay, Florida and the surrounding area between November 2007 and December 2010. TPO status was determined during pregnancy and fetal/infant brain and body growth variables were assessed at delivery. A subsample of forty-one (41) mother-infant dyads participated in a 6-month longitudinal supplemental study. Infant growth assessments were conducted at 3, 4, 5 and 6 months postpartum. Regression analysis revealed maternal TPO positivity was significantly associated with smaller head circumference, reduced brain weight and lower brain-body-ratio; however maternal race/ethnicity was identified as an effect modifier in the relationship. No significant differences were noted in birth weight, birth length, abdominal circumference or chest circumference measurements among infants born to TPO positive mothers of any racial/ethnic group as compared to their negative counterparts. Mixed model analysis of the smaller subset (n=41) revealed infants of TPO+ mothers were smaller at birth but experienced accelerated growth between birth to 3 months when compared to infants born to TPO- mothers. This acceleration led to their catch-up in growth to their TPO negative counterparts by 3 months of age. No significant differences were noted in neurocognitive outcomes between infants born to TPO+ mothers compared to those born to TPO- mothers. The findings in this dissertation indicate that maternal/race ethnicity modifies the relationship between TPO positivity and reduced fetal/infant brain growth. Additionally, the analyses suggest that maternal autoantibody status could lead to variations in early infant growth and development. The end-result of these variations is unclear. Further research is needed to determine the potential impact of reduced head circumference and accelerated growth as it relates to long-term neurocognitive consequences. Currently, TPO antibody status is not assessed as part of the standard prenatal care laboratory work-up, but findings from this study suggest that fetal brain growth may be impaired by TPO positivity among certain populations, therefore autoantibody screening among high-risk sub-groups may be useful for clinicians to determine whether prenatal thyroid treatment is warranted.
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Hussey, I. W. "The influence of notch stress field on fatigue crack growth." Thesis, University of Portsmouth, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372739.
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Smallfield, B. M. "Influence of straw residues on the growth of winter wheat." Thesis, University of Reading, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292951.
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Given, M. J. "The influence of ions on water tree growth in polyethylene." Thesis, University of Strathclyde, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381492.
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RondoÌ, PatriÌcia Helen de Carvalho. "The influence of maternal nutritional factors on intrauterine growth retardation." Thesis, University of London, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248112.
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Li, Zhongxia. "Influence of growth selection on the immunological system of Turkeys /." The Ohio State University, 1999. http://rave.ohiolink.edu/etdc/view?acc_num=osu148818704954115.
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Atiyeh, Rola M. "Mechanisms by which earthworm-processed organic wastes influence plant growth /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488195154357267.
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Klinka, Karel, R. E. (Reid E. ). Carter, Qingli Wang, and M. C. (Michael Charles) Feller. "Influence of salal on height growth of coastal douglas-fir." Forest Sciences Department, University of British Columbia, 2001. http://hdl.handle.net/2429/677.
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The influence of salal on tree growth has attained considerable attention in coastal British Columbia. Field observations, surveys, and studies in the CWH zone have indicated poor growth performance of crop tree species in salal-dominated plantations and natural immature and old-growth stands. Where sites have been burned and planted, tree growth has improved; similar effects have been observed for naturally regenerated stands. Immature stands that developed after wind disturbance or harvesting feature rapid growth and nearly complete absence of salal. As studies have shown that ericaceous plants negatively impact tree growth, the salal on potential harvest sites has been considered undesirable.
This study examined (1) the possible influence of salal on the stand, soil nutrient status and site index, and (2) the relations between site index, salal, plant communities, and site in disturbed, immature, coastal Douglas-fir ecosystems. We compared vegetation and environmental characteristics of 101 ecosystems, and examined differences in foliar and
soil nutrient characteristics and site index between stands with high and low salal cover through analysis of variance (ANOVA) and regression analysis.
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McIlroy, Marie. "The influence of microvascular pericytes on endothelial cell characteristics and gene expression." Thesis, University of Ulster, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272336.
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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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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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Martin, Christopher School of Biomedical Engineering UNSW. "Investigation of exogenous growth factors; platelet derived growth factor, insulin-like growth factor binding protein and fibroblast growth factor, and their influence on in vivo bone repair." Awarded by:University of New South Wales. School of Biomedical Engineering, 2006. http://handle.unsw.edu.au/1959.4/30405.
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This research investigated if exogenous growth factors (GFs), in particular platelet derived growth factor (PDGF), has an in vivo effect on the healing response of normal healthy bone. The research was orientated to study whether a clinical beneficial effect could be demonstrated. To achieve this two animal models were utilised, namely, a rabbit tibial osteotomy model and an ovine tibial defect and porous implant ingrowth model. The rabbit model comprised of a unilateral V-shaped tibial osteotomy, stabilised with an absorbable intramedullary pin and figure-of-eight tension band suture, with a 3 week survival period. The GFs tested in this model were 3 concentrations of PDGF, a single dose of insulin-like growth factor binding protein (IGF-BP) and a combination of the two. Each osteotomy was injected with a single bolus of collagen (control) or collagen containing GF (treatment) during surgery. After sacrifice tibiae were CT-scanned in situ, harvested and subject to 4-point bend testing. The callus, underlying bone and contralateral bone's greyscales and mechanical testing results were used for comparative analysis. The ovine model consisted of implanting 6 small rectangular shaped titanium alloy porous implants and one empty defect bilaterally in sheep's tibiae, for 4 and 6 weeks. The sheep were injected with tetracycline bone marker at 2 week intervals. The model's characteristics and any positional effects were initially investigated. Followed by an investigation into the influence of various exogenous GFs on the healing response and ingrowth characteristics of bone into the porous implants. The GFs investigated were PDGF, IGF-BP and fibroblast growth factor impregnated into the porous implants in a collagen carrier. Comparative analysis was done on results from 3-point bend testing of the bone/implant interface, image analysis to quantify percentage of bone, from scanning electron microscopy images of implant sections and confocal microscopy images of tibial defect sections. Analyses indicate that the GFs investigated have a direct and quantifiable positive in vivo effect. The more significant finding is that the growth factors have a potent systemic effect. These results were confirmed by both the sheep porous bone plug model and the rabbit tibial osteotomy model used within this research.
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Mongerard-Coulanges, Medge. "Influence de l'expression du facteur de croissance VEGF sur l'activité antitumorale de l'alendronate." Paris 6, 2009. http://www.theses.fr/2009PA066596.
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Les cellules A431 qui proviennent d’un carcinome épidermique manifestent une résistance transitoire (24h) à l’activité antitumorale de l’alendronate (aminobisphosphonate). Ces cellules ont la particularité de surexprimer le récepteur EGFR (Epidermal Growth Factor Receptor) et produisent son ligand TGF (Transforming Growth Factor Alpha). Cette voie autocrine impliquée dans la prolifération cellulaire ne suffit pas, à elle seule, à expliquer cette résistance. Ce phénomène serait directement lié au niveau d’expression élevé d’un facteur de croissance de l��endothélium vasculaire : VEGF (Vascular Endothelial Growth Factor). Comme beaucoup de cellules tumorales, les cellules A431 expriment des récepteurs à VEGF. VEGF, par des voies autocrines, favorise la survie des cellules A431. De plus, cette étude a montré que VEGF régule la production de TGF par les cellules A431. L’association de l’alendronate et d’un antisens dirigé contre VEGF permet de s’affranchir de ce phénomène de résistance transitoire, permettant une diminution de la production de VEGF par les cellules A431 et une meilleure inhibition de la prolifération cellulaire dès les premières 24h.
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Van, Regemorter Tanguy. "The Influence of Dopants on the Growth of Diamond by CVD." Doctoral thesis, Uppsala universitet, Institutionen för materialkemi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9539.
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Diamond is an important material in many industrial applications (e.g., machining of hard materials, bio-electronics, optics, electronics, etc.) because of its exceptional properties such as hardness, tolerance to aggressive environments, compatibility with human tissues, and high carrier mobility. However, a highly controlled method for growing artificial high-purity diamond on a range of different substrates is needed to exploit these exceptional properties. The Chemical Vapour Deposition (CVD) method is a useful tool for this purpose, but the process still needs to be developed further to achieve better control of growth. In this context, the introduction of dopant species into the gas phase has been shown to strongly influence growth rate and surface morphology. Density Functional Theory (DFT) methods are used to deepen our atomic-level understanding of the effect of dopants on the mechanism for CVD growth on diamond. More specifically, the effect of four dopants (N, P, B and S) has been studied on the important reaction steps in the growth mechanism of diamond. Substitution of N into the diamond lattice has generally been found to disfavour critical reaction steps in the growth of the 100-face in diamond. This negative effect has been related to electron transfer from the N dopant into an empty surface state, e.g., a surface carbon radical. In addition, strong surface stabilization is observed for N substitution in certain sites via a beta-scission reconstruction, with the formation of sp2 carbon. These observations correlate well with observed surface degradation and decrease in growth rate when a high concentration of nitrogen gas is introduced into the CVD growth process. The effect of co-adsorbed P, S and B onto the diamond surface has also been investigated for two reaction steps: CH3 adsorption and H abstraction. While P and B are observed to influence these reaction steps, the effect of S is rather limited.
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Duffy, Danelle M. "Influence of supramammary lymph node extract on cell growth in vitro." Connect to this title online, 2007. http://etd.lib.clemson.edu/documents/1181251756/.
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Rapp, Moritz. "The influence of the chemokine CCL22 on tumor development and growth." Diss., Ludwig-Maximilians-Universität München, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-183687.
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Nicollet, Andréa. "The influence of growth temperature on CVD grown graphene on SiC." Thesis, Linköpings universitet, Halvledarmaterial, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-119919.
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Graphene is one of the most popular material due to its promising properties, for instance electronics applications. Graphene films were grown on silicon carbide (SiC) substrate using chemical vapor deposition (CVD). Influence of the deposition temperature on the morphology of the films was investigated. Characterizations were done by reflectance mapping, atomic force microscopy and Raman spectroscopy. Two samples were done by sublimation process, to compare the number of layers and the morphology of the graphene films with the one grown by chemical vapor deposition.The reflectance mapping showed that the number of layers on the samples made by CVD was notinfluenced by the deposition temperature. But also, demonstrated that sublimation growth is present in allthe samples due to the presence of silicon coating in the susceptor. The growth probably started by sublimation and then CVD deposition. The step morphology characteristic of the silicon carbide substrate surface was conserved during the deposition of graphene. But due to surface step bunching, a decrease inthe step height occurred and the width of the terraces increased. The decreasing in deposition temperature leads to a smoother surface with the CVD method. Raman spectroscopy confirmed the presence ofgraphene and of the buffer layer characteristic of the sublimation growth. Moreover, it demonstrated the presence of compressive strain in the graphene layers.
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Powell, Brian Edward. "The influence of minor cycles on low cycle fatigue crack growth." Thesis, University of Portsmouth, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354380.
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Fatigue crack propagation rates have been measured for two titaniumbased aeroengine disc alloys using compact tension test pieces. The loading block employed simulates two features of the engine flight pattern. A major stress cycle represents the start-stop operation which leads to low cycle fatigue. In-flight vibrations, which may give rise to high cycle fatigue, are represented by superimposed minor cycles of high frequency. This combined loading is applied in a specially developed test facility consisting of an electromagnetic vibrator mounted above a servohydrau1ic actuator. When the minor cycles are inactive the fractographic cracking processes are those associated with major cycle crack growth. Once active, the minor cycle growth may either generate extensive cyclic cleavage or increase the separation of the fatigue striations associated with the periodic major cycles. The contribution of the minor cycles to the total growth rate is dependent on their relative number and size. In gas turbine and compressor discs and blades, components which experience large numbers of minor cycles per flight, the damage associated with active minor cycles is dominant. Consequently, the onset of minor cycle damage effectively determines the useful life of such components. The threshold values associated with the minor cycles have been used to predict the onset of minor cycle activity. Similarly the method of linear superposition has been used to predict the subsequent fatigue crack growth rates. These predictions are successful for Ti-6Al-4V, whilst for Ti-5331S they are either found to be accurate or safe. Although Ti-5331S displays a marginally greater resistance to the onset of minor cycle crack growth, of greater significance is its reduced crack growth rates prior to this event. As a consequence components fabricated from Ti-5331S will exhibit longer fatigue crack propagation lives when subjected to the conjoint action of high and low cycle fatigue.
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Kim, Junghoon. "The influence of force production and eccentric exercise on growth hormone." Virtual Press, 1997. http://liblink.bsu.edu/uhtbin/catkey/1048386.
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The main purpose of this study was to investigate the relationship between human growth hormone (hGH) and two separate components of resistance exercise. Eight non-weight-trained subjects (23.33 ± 0.3 yrs) performed three force production trials (FPT), at different concentric workloads, and an 120% eccentric exercise trial (EET) on the Cybex 6000. Blood samples (3 mls) were taken pre- and post-exercise and analyzed for lactate, creatine kinase (CK) and hGH. Electromyographic (EMG) activity of the quadriceps muscle was recorded during each trial. The mean peak torque produced during the FPTs increased as work intensity increased but was the highest in the EET. The data for total work showed a proportional relationship with the intensity of the three concentric work loads but not the 120% EET. EMG activity of vastus medialis (VM) and rectus femoris (RF) measured during EET was 26% less than RF of 50% and 15% less than VL of 70% in FPT, respectively. The highest hormonal response occurred following the 120% EET. The hormonal response following the FPTs was highest in the 90% FPT with the two lower work intensity trials (50 and 70%) showing no clear hormonal response. Although the hGH response was the highest in the 120% EET, the post-exercise lactic acid levels in EET were 24% less than that of the 90% FPT. Creatine kinase (CK) activity was significantly elevated 36 hours after the last bout of EET which suggests that the eccentric exercise resulted in muscle damage. The results from concentric trials showed that muscle force generation, EMG, and lactic acid of the three different concentric trials were well correlated to the pattern of hGH secretion. However, only peak torque was consistent with the hGH response of the EET. The highest peak torque and hGH levels were achieved with eccentric exercise. The highest levels of fatigue, as a result of the combination of longer exercise time and overloading of the muscle during EET, may explain the higher hGH output. The muscle damage caused by the eccentric trial was enough to induce delayed onset of muscle soreness and may be the stimulus for the higher hGH output. The hGH response may facilitate repair of the muscular damage induced by eccentric exercise by promoting protein synthesis.<br>School of Physical Education
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Fletcher, Richard John Royston. "The influence of oscillating magnetic fields on microbial growth and corrosion." Thesis, University of Portsmouth, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430655.
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Bracegirdle, Philippa. "The influence of growth environment on the virulence of Listeria monocytogenes." Thesis, Open University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298982.
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Kensara, Osama Adnan. "Influence of fetal growth on current body structure and metabolic function." Thesis, University of Southampton, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439386.
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Mikkelsen, Helga. "Influence of growth mode and aminoglycoside antibiotics on Pseudomonas aeruginosa physiology." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611950.
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Unruh, Bryan Jacob. "Influence of nitrogen on weed growth and competition with grain sorghum." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/15143.
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Master of Science<br>Department of Agronomy<br>Johanna Dille<br>Nitrogen (N) fertilizer intended for the crop may benefit highly competitive weeds to the detriment of the crop. A field experiment was conducted in 2009 to determine the influence of increasing N fertilizer rates and increasing Palmer amaranth densities on weed biomass and grain sorghum biomass and yield. Three rates were 0, 67, and 134 kg N ha-1 and natural populations of Palmer amaranth were thinned to densities of 0, 0.5, 1, 2, 4, and 8 plants m-1 of row. Palmer amaranth biomass increased as weed density and N rates increased. Weed-free grain sorghum yields were similar across all three N rates, and parameter estimates of yield across Palmer amaranth densities were not different between N rates. Based on the parameter estimates from the rectangular hyperbola model, initial slope (I) as density approached zero was 16%. Maximum expected yield loss (A) at high Palmer amaranth densities was 68%. Palmer amaranth showed a high response to N and the higher N rate increased the ability of the weed to reduce grain sorghum yield. A greenhouse experiment was conducted to determine the influence of six N rates on growth of six selected plant species, including grain sorghum, soybean, yellow foxtail, velvetleaf, Palmer amaranth and shattercane. Covariance analysis was performed with N rate as a covariate. Biomass of all species increased as N rate increased in both runs of the study. Soybean responded the least to N rate of all species in regards to biomass, height and leaf area production. In the first run, the biomass of three grass species (grain sorghum, yellow foxtail, shattercane) had similar estimates of slope and intercept of biomass across N rates. In the second run, the biomass slopes of grain sorghum and shattercane differed from soybean and were the only slopes that differed between species. Palmer amaranth had the highest rate of response as N increased but slopes of height were similar for Palmer amaranth, grain sorghum and shattercane. Soybean leaf area slopes were different from grain sorghum, yellow foxtail, and velvetleaf, but all other slopes were not different among species. Addition of N to grain sorghum increased weed growth and resulted in more yield loss as a result of weed density. The greenhouse study demonstrated that grain sorghum and Palmer amaranth increased in response similarly to the addition of N. Alternative N fertilizer management could play a role in minimizing Palmer amaranth impacts in grain sorghum production.