For evolution to occur over time, it is necessary for animals and plants to show phenotypic variation. If the individuals within populations of a species do not show observable differences among themselves, there will be a lack of driving force for natural selection to act on and decide which characteristic gets inherited from one generation to the next. It is hence important to study phenotypic variation, especially against environmental gradients such as latitude and altitude, which gives us an insight into the pattern of change according to essential factors such as temperature and length of seasons. The latter would impose time constraints on growing populations, leading to periods of unfavourable conditions limiting their growth and development. In many cases, such organisms would tend to compensate for the period of slow growth and catch up to the others that did not have to endure the same situation and grow to the same size as them. This study aims to find differences in three key larval life-history traits of the moor frog (Rana arvalis), namely metamorphic mass, larval period, and growth rate, and find what kind of pattern is observed in case of these phenotypic variations. It also aims to find differences in the strength of compensatory response between populations from lower and higher latitudes. A common garden experiment was conducted with populations originating from both sides of the Baltic Sea, ranging from southern Sweden and Latvia to central Finland and northern Sweden. It was expected that the northern populations would grow faster and show a countergradient variation pattern since they are faced with more strict time constraints at higher latitudes, but in most cases, we observed a co-gradient pattern, wherein the environmental effect amplifies the individual’s genetic predisposition instead of opposing it. We also observed a stronger compensatory response in the northern populations as compared to their southern counterparts. Effects of climate change and subsequent rise in temperatures making the environment unpredictable over time could be used to speculate about the reason behind the results obtained. Epigenetics could also be used as an approach to study long lasting changes in an organism’s gene expression to make it adapt better to changing conditions and hence show different patterns of variation from studies in the past. Studying such changes, expected or not, is important to keep up with the needs of the species that require conservation, and will help conservation biologists to formulate strategies that would be effective even in the face of constant change in the world.

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yes / Does exercise promote weight loss? One of the key problems with studies assessing the effi cacy of exercise as a method of weight management and obesity is that mean data are presented and the individual variability in response is overlooked. Recent data have highlighted the need to demonstrate and characterise the individual variability in response to exercise. Do people who exerc ise compensate for the increase in energy expenditure via compensatory increases in hunger and food intake? The authors address the physiological, psychological and behavioural factors potentially involved in the relationship between exercise and appetite, and identify the research questions that remain unanswered. A negative consequence of the phenomena of individual variability and compensatory responses has been the focus on those who lose little weight in response to exercise; this has been used unreasonably as evidence to suggest that exercise is a futile method of controlling weight and managing obesity. Most of the evidence suggests that exercise is useful for improving body composition and health. For example, when exercise-induced mean weight loss is <1.0 kg, signifi cant improvements in aerobic capacity (+6.3 ml/kg/min), systolic (¿6.00 mm Hg) and diastolic (¿3.9 mm Hg) blood pressure, waist circumference (¿3.7 cm) and positive mood still occur. However, people will vary in their responses to exercise; understanding and characterising this variability will help tailor weight loss strategies to suit individuals.

The nation's Section 404 permitting program, of the Clean Water Act (CWA), represents one of the longest regulatory histories of designing and implementing credit trading programs to satisfy regulatory requirements. The role and the function of in-lieu fee (ILF) programs in supporting this regulatory structure have undergone a substantial change. For the first time in the history of the Sec. 404 program, 33 CFR Part 332 and 40 CFR Part 230, Subpart J (the "2008 mitigation rule" or "rule"), prioritizes the use of off-site mitigation over on-site-mitigation. Additionally, the rule prioritizes advanced, third-party mitigation; especially as achieved through mitigation banks; over any off-site compensatory mitigation provided by ILF programs (33 CFR 332.3(b)(1)). This new regulatory environment favors the use of commercial mitigation bank credits while acknowledging that the limited permittee demand of off-site mitigation credits, in particular areas, justifies the continuing need for ILF programs (Corps and EPA 2008, p.19606,19611). This research examines how regulatory officials use ILF programs under the 2008 mitigation rule, and, it determines the extent to which ILF programs are capable of fulfilling the role envisioned for them under the 2008 mitigation rule. Simulation results indicate that commercial mitigation banks cannot meet risk adjusted returns under limited credit demand conditions. ILF programs offer some additional financial capacity to fill the void in commercial bank coverage; but, this potential is limited in low demand conditions. Furthermore, empirical case studies of a Virginia and Georgia provide evidence that regulatory officials rely on ILF programs to provide off-site compensatory mitigation almost exclusively in the absence of private credit supply, as intended in the 2008 rule. Evidence in Georgia and Virginia also indicate that, in some situations, ILF programs face difficulties in providing mitigation under the constraints of limited demand and more stringent regulatory requirements. / Master of Science

Antibiotic resistance is a growing problem on a global scale. Increasing numbers of bacteria resistant toward one or multiple antibiotics could return us to the high mortality rates for infectious diseases of the pre-antibiotic era. The need for development of new classes of antibiotics is great as is increased understanding of the mechanisms underlying the development of antibiotic resistance. We have investigated the emergence of resistance to peptide deformylase inhibitors, a new class of antibiotics that target bacterial protein synthesis. The fitness of resistant mutants as well as their propensity to acquire secondary compensatory mutations was assessed in order to gain some insight into the potential clinical risk of resistance development. Most of this work was done in the bacterium Salmonella typhimurium, due to the availability of excellent genetic tools to study these phenomena. In addition, we have studied the bacterium Staphylococcus aureus as peptide deformylase inhibitors have been shown to have the greatest effect on Gram-positive organisms. In the course of this work we also examined the mechanistic aspects of translation initiation. Using a cell-free in vitro translation system we studied the effects of various components on translation initiation. These results have been combined with results obtained from resistant and compensated bacterial strains in vivo to gain new insights into the mechanisms of translation initiation.

Cost and benefits of high individual growth rates are likely to vary across different environments leading to geographic differentiation in growth strategies. In ectotherms, habitats constrained by short growing seasons favour rapid growth and development leading to adaptive latitudinal clines in these traits. Geographic variation in growth strategies should be influenced by physiological variation as well as environmental factors, however many of these mechanisms remain largely unexplored. In my thesis, I studied hormonal correlates of growth strategies, and compensatory responses to phenological variation and environmental stress in anuran tadpoles. I tested the hypotheses that fast growing high latitude common frog Rana temporaria tadpoles have higher growth hormone (GH) expression, and low stress hormone (CORT) elevation in response to predator stress. I found no relationship between GH expression and latitude, but CORT response decreased with latitude after 24 hours of predator exposure. Lower CORT response at high latitude can be adaptive as it may enable the tadpoles to maintain high growth in time constrained habitats. I also found that breeding phenology affected latitudinal variation in growth, development and anti-predator strategies. Northern R. temporaria tadpoles were phenotypically more similar to southern tadpoles when breeding occurred early, suggesting that part of the latitudinal variation is plastic and affected by yearly variation in phenology. When time stress was manipulated by delaying hatching, tadpoles were able to compensate by increasing their development and growth during the larval stage, decreasing the cost of the delayed development. In the final study, I found that northern tadpoles showed stronger compensatory growth during the larval stage than southern tadpoles after being delayed by low food, however, temperature manipulation did not induce differences in the compensatory responses. In general, my results highlight the roles of both environmental and genetic variation in determining individual growth strategies. / Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 735

This master’s final thesis is purposive to analyze the International compensatory system on the damage caused by oil pollution. There are discussed the stages of the formation of the current system identifying the concrete premises, which have determined the origin of each compensatory level and its obliged regulation. There is indicated that every tanker which is responsible under this system has to face strict liability. Specific attention has been paid to each separate element of this system and uncover characteristic features for it. After research concluded in the master’s final thesis there are defined that at this moment operate particular compensatory system which ensure the reimbursement for every damage caused by oil spill. Although this system has been prevailing for 40 years but it always had to face with financial difficulties which were impacted by more and more tankers incidents in the sea. Thereby, for the lean working of this system there must be implanted prevented measures which ensure much safer navigation at sea. Also there is discussed new third compensatory element which have started to operate since 2005 years but it still hasn’t happened any major tanker’s incident to test how this element can cope with financial burden in reality. In the master’s final thesis there talked over the first and the second compensatory elements and international compensatory funds which are recognized as intergovernmental organizations responsible for these compensatory... [to full text]

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Master of Science / Department of Animal Sciences and Industry / Michael D. Tokach / A total of 5,212 nursery pigs were used in 11 experiments to evaluate amino acids in nursery pig diets. Experiments 1 and 2 were conducted to determine whether the Lys level fed during one phase of the nursery influenced the response to Lys during subsequent phases. Experiment 1 tested a wide range of dietary Lys in 2 phases and reported that pigs fed high Lys during each period had increased growth performance; however, compensatory growth occurred for the pigs previously fed low Lys diets, resulting in no impact on overall ADG or final BW. Experiment 2 tested a narrow range of dietary Lys in 3 phases and found that marginally deficient diets can be fed in the early nursery phases without influencing final BW or the response to Lys levels in subsequent phases. Both experiments demonstrate that the low dietary Lys levels used in each can be fed in the early nursery phases with no negative impact on overall nursery growth rate provided that adequate levels are fed thereafter. Experiments 3 to 6 were conducted to determine the standardized ileal digestible (SID) Lys requirement of nursery pigs from 7- to 14-kg. Data from all experiments were combined and break-point and quadratic broken-line analysis was used to determine the estimated SID Lys requirement. The SID Lys requirement for optimal growth was at least 1.30% for ADG and 1.37% for G:F, or at least 3.86 and 4.19 g SID Lys/Mcal ME, respectively. Experiments 7 to 11 were conducted to evaluate the effect of replacing specialty protein sources with crystalline AA and AA requirements for 7- to 12-kg pigs. Experiment 7 demonstrated that crystalline AA can be used to replace fish meal in diets with no negative effects on growth performance. Experiment 8 demonstrated that L-Trp, L-Val, and a source of non-essential AA were needed in low-CP, AA-fortified nursery diets to achieve maximum growth performance, whereas the addition of L-Ile was not required. Experiment 9 indicated that feeding greater than 7.35% total Lys:CP decreased growth performance and Exp. 10 indicated that a SID Val:Lys ratio of 65% was sufficient for optimal growth of early nursery pigs. Implementing the results from the previous experiments, Exp. 11 determined that crystalline AA in nursery pigs diets can replace high amounts of fish meal, meat and bone meal, and poultry meal when balanced for minimum AA ratios and maximum Lys:CP with no negative effect on growth performance.