Dissertations / Theses on the topic 'Environmental effects'
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Zobel, Thomas. "Environmental management systems : policy implementation and environmental effects." Doctoral thesis, Luleå, 2005. http://epubl.luth.se/1402-1544/2005/32.
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Wilson, Jodie Sarah Maria. "Environmental endocrine disruptors : their effects on the environment and health." Thesis, Queen's University Belfast, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709860.
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Endocrine disrupting compounds (EDCs) can disrupt normal hormone signalling and production, and potentially contribute to a range of adverse effects on the environment and health. In vitro bioassay analysis was performed (mammalian reporter gene assays; RGAs) to assess the hormone receptor activity of common wastewater contaminants at environmentally relevant concentrations. The estrogenic enhancing capabilities of three parabens, 4-tert-octylphenol, carbamazepine and ketoconazole were identified; carbamazepine also disrupted glucocorticoid receptor (GR) transcriptional activity. In addition, RGAs were used, coupled with a high content analysis (HCA) assay, to investigate the potential for persistent organic pollutants (POPs) to induce stress responses via disruption of the GR. PFOS, PFDA, BDE-47 and p,p’-DDE altered mammalian stress responses. HCA was also used to investigate chemically defined POP mixture induced toxicity on a liver cell model and successfully detected early signs of cellular stress. While it is important to understand and classify the effects of contaminants, it is also crucial to gain information about their presence in the environment. To this end a UPLC MS/MS method was developed to monitor fifteen common aquatic contaminants. Screening of wastewater treatment work effluent revealed 10 of the 15 contaminants were still detectable after WWTW treatment. Furthermore anthropogenic pollution was evident in the rural catchment rivers. These catchments also have the phenomenon of unexplained static biological water recovery. The prevalence of EDC activity was investigated using an effect-directed bioassay analysis approach. Areas of concern were highlighted (androgen receptor and GR antagonism). Furthermore a statistically significant association between GR antagonism and average score per taxon (ASPT) values (a measure of biological water quality) was highlighted for one catchment. The use of novel techniques as HCA can help advance knowledge on mixture effects due to the ability to incorporate multiple parameters. The ability to detect pre-lethal signs of cellular stress is important for risk assessment. Furthermore, this thesis shows the importance of constant and updated screening methods of environmental waters. The inclusion of bioassays for screening water samples gives valuable information which targeted methods are unable to provide.
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Schylander, Elisabeth. "Environmental effects and organizational experiences of environmental management systems /." Luleå, 2004. http://epubl.luth.se/1402-1757/2004/31/index.html.
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Hampel, Regina. "Environmental effects and gene-environment interactions: air pollution and temperature effects on cardiovascular risk factors." Diss., lmu, 2011. http://nbn-resolving.de/urn:nbn:de:bvb:19-138583.
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Lampa, Erik. "Mixture Effects of Environmental Contaminants." Doctoral thesis, Uppsala universitet, Arbets- och miljömedicin, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-237690.
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Chemical exposure in humans rarely consists of a single chemical. The everyday exposure is characterized by thousands of chemicals mainly present at low levels. Despite that fact, risk assessment of chemicals is carried out on a chemical-by-chemical basis although there is a consensus that this view is too simplistic. This thesis aims to validate a statistical method to study the impact of mixtures of contaminants and to use that method to investigate the associations between circulating levels of a large number of environmental contaminants and atherosclerosis and the metabolic syndrome in an elderly population. Contaminants measured in the circulation represented various classes, such as persistent organic pollutants, plastic-associated chemicals and metals. There was little co-variation among the contaminants and only two clusters of PCBs could be discerned. Gradient boosted CARTs were used to assess additive and multiplicative associations between atherosclerosis, as measured by the intima-media thickness (IMT) and the echogenicity of the intima-media complex (IM-GSM), and prevalent metabolic syndrome. Systolic blood pressure was the most important predictor of IMT while the influence of the contaminants was marginal. Three phthalate metabolites; MMP, MEHP and MIBP were strongly related to IM-GSM. A synergistic interaction was found for MMP and MIBP, and a small antagonistic interaction was found for MIBP and MEHP. Associations between the contaminants and prevalent metabolic syndrome were modest, but three pesticides; p,p’-DDE, hexachlorbenzene and trans-nonachlor along with PCBs 118 and 209 and mercury were the strongest predictors of prevalent metabolic syndrome. This thesis concludes that many contaminants need to be measured to get a clear picture of the exposure. Boosted CARTs are useful for uncovering interactions. Multiplicative and/or additive effects of certain contaminant mixtures were found for atherosclerosis or the metabolic syndrome.
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Cox, Paula R. "Environmental effects of rodenticide use." Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316195.
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Saci, R. "Boundary effects on environmental vortices." Thesis, University of Manchester, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370979.
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Vezzoli, Andrea. "Environmental effects in molecular electronics." Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2031980/.
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Researchers have looked at the possibility of using single molecules as functional building blocks in electronics circuits since the 1970s. The field of molecular electronics, despite its experimental and theoretical challenges, has continued to grow incessantly from a simple scientific curiosity to an emerging field with hundreds of publications per year. Thanks to the development of scanning probe microscopy a variety of techniques currently used to characterise the electrical properties of single molecules has been developed, and molecular systems mimicking the behaviour of traditional electronic components, such as transistors or rectifiers, have been prepared. Despite the obvious fact that supramolecular interactions must play a role in the charge transfer process, only a small number of reports on the subject have been published. In this thesis a set of molecular wires with an oligothiophene central unit, sandwiched between two insulating chains, has been used to probe the effect of such interactions on molecular conductance using several scanning tunnelling microscopy techniques. It has been found that the side-chain length has little effect on molecular conductance, but the presence of water in the surrounding environment triggers an increase in conductance and a switch in the behaviour from activationless to thermally-activated. Furthermore, upon exposure to electron-withdrawing small molecules, these oligothiophene molecular wires form charge transfer complexes, with conductance enhanced by a factor up to 100. Measurements performed in UHV confirmed the observed behaviour, and theoretical calculations were performed to explain it in the coherent tunnelling regime. A gateway state arising from coupling of the molecular backbone to the sulfur contacts accounts for the observed shallow decay of conductance with length, while shifting of transport resonances upon interaction with water and the appearance of interference features upon charge transfer complexation explained the temperature dependence and the conductance enhancement, with experimental observation closely matched by DFT calculations.
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Lunsford, Garrett P. "Environmental effects on student performance /." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1885755991&sid=4&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Lunsford, Garrett Paul. "Environmental Effects on Student Performance." OpenSIUC, 2009. https://opensiuc.lib.siu.edu/theses/11.
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AN ABSTRACT OF THE THESIS OF Garrett P. Lunsford, for the Masters degree in Architecture, presented on July 10th 2009, at Southern Illinois University Carbondale. TITLE: ENVIRONMENTAL EFFECTS ON STUDENT PERFORMANCE MAJOR PROFESSOR: Dr. Walter Wendler With the increasing concern for sub par student performance in America, it has become more vital than ever for designers to create optimal learning environments. Student performance is significantly dependent on the quality of teaching as well as the pupil-instructor relationship. However, it is rare for even our best instructors to receive adequate performance from their students when teaching in poor environments. Research for more than 30 years has displayed explicit correlation between physical characteristics of school buildings and educational outcomes. These physical characteristics include lighting, acoustics, thermal control, indoor air quality, as well as class size. By taking each of these factors into consideration, architects can produce settings that do not hinder student performance. Better educated children today will make the world a smarter, improved, more sustainable environment tomorrow.
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Pike, Christopher G. "Environmental effects on ions and atoms." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240086.
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Smith, Rory. "Environmental effects on dwarf galaxy evolution." Thesis, Cardiff University, 2009. http://orca.cf.ac.uk/54852/.
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Using an N-body/Tree-code and Smoothed Particle Hydrodynamics, the influence of ram pressure stripping and harassment on an infalling star-forming galaxy population is investigated. In combination these mechanisms act to strip late-type dwarfs of their gas content in less than 0.5 Gyrs, causing a cessation of star-formation. As a result, late-type dwarfs evolve to colours typical of cluster dwarf ellipticals in less than 2 Gyrs, although the period in which they would be classified as transition objects lasts less than 1 Gyr. The rapid removal of a significant fraction of the dwarfs disk mass by ram pressure stripping causes morphological transformation of the stellar component, producing rotation-to-dispersion ratios in agreement with observations of cluster dwarf ellipticals. A Monte-Carlo simulation is utilised to quantify the effects of harassment, and strong, disruptive tidal encounters are found to be rare. The typical observable con sequences of harassment are found to be minor, producing very low surface brightness features (visible at surface brightnesses limits of > 30/j,b arcsec 2), and a reduction in dynamical mass-to-light ratios by roughly a factor of 2. The influence of harassment is found to be highly sensitive to the disk scale-length in exponential disks, and much less so to the mass of the galaxy. In general, ram pressure stripping is found to dominate the environmental influences on infalling late-type dwarfs, while the inclusion of the harassment model produces second-order effects only. Ram pressure stripping appears capable of forming the observed cluster dwarf population, both in colour and in morphology.
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Chandler-Wilde, S. N. "Ground effects in environmental sound propagation." Thesis, University of Bradford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384241.
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Garrison, Trent. "The Environmental Effects of Coal Fires." UKnowledge, 2015. http://uknowledge.uky.edu/ees_etds/31.
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There are thousands of subterranean coal fires in the world that, because of incomplete combustion, emit a wide variety of volatile and semivolatile organic compounds to the atmosphere, water, and soil at concentrations that could pose health risks to humans and wildlife. The main goals of this study were to (1) review methods that are used to characterize physical and chemical characteristics of coal-fire sites, (2) determine relationships between gas emissions and physical and chemical characteristics of coal-fire sites, using a combination of regression and multivariate statistical methods, and (3) determine the concentrations of volatile and semivolatile organic compounds in water and soil at two coal-fire sites in eastern Kentucky. More specifically:
The objective of Chapter 1 was to review past works and list technologies used over time. Eight years of coal-fire collection technologies were reviewed. A variety of methods and technologies were identified. Qualitative and quantitative preferences were noted.
The objective of Chapter 2 was to identify and list uncontrolled coal-fire variables. These variables include complete/incomplete combustion; fire temperature and size; distance to fire; relative humidity and moisture in the system; geology, geochemistry, and age of coal; condition of the mine, sampling time of day; sampling equipment differences; and human error. A secondary objective of this chapter was to determine which coal-fire gases have strong relationships by using the principal component analysis (PCA) software JMP. The strongest relationship was between CO and H2S. Temperature and CH4 were also important. This indicates that incomplete combustion and polynuclear aromatic hydrocarbon (PAH) formation are likely occurring, setting the stage for Chapter 3.
The objective of Chapter 3 was to identify and define the extent of soil and water hydrocarbon contamination at the Truman Shepherd and Lotts Creek coal fires in eastern Kentucky. No groundwater contamination was detected at either location. Soil contamination was found at both, but was much higher at Lotts Creek, potentially because of sorption onto soil organic matter (which is reduced at Truman Shepherd by an excavation attempt) and other physicochemical mechanisms. Soil contamination was localized to relatively small areas around coal-fire vents.
Based on the results, future studies should consider: Attempting to duplicate these results in other geologic regions Quantifying greenhouse gas emissions from coal fires to consider their contribution to climate change. Coal-fired power plants are regulated, but coal fires, which produce many more harmful gases, are not Determining the feasibility of an oxygen-injection system to engender more complete combustion, therefore possibly reducing harmful gases Determining the feasibility of electricity production from coal fires Adopting a consistent federal coal-fire policy
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Furrow, Keith W. "Environmental effects on stitched RTM composites." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09122009-040516/.
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Zwickle, Adam K. "Communicating Environmental Risks." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397500693.
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Wilson, Martin Robert. "Pulmonary inflammatory effects of environmental and surrogate environmental particulates and their components." Thesis, Edinburgh Napier University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270524.
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Mann, Adrian B. "Nano-mechanical measurements : surface and environmental effects." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318924.
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Walling, Craig Anthony. "Environmental effects on reproductive decisions in fish." Thesis, University of Glasgow, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433247.
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Beck, Ryan. "Effects of Environmental Regulation on Innovation Decisions." Thesis, Boston College, 2010. http://hdl.handle.net/2345/1346.
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Thesis advisor: Hideo KonishiThis paper will review prior research to support the notion that innovation does in fact lead to a competitive advantage for business, and that this competitive advantage is translated into increased profitability and productivity. Though the body of work reviewed here will by no means unequivocally prove that this relationship always holds true in real-world markets, it will provide a convincing argument that fostering innovation will likely have positive economic affects. Building off this assumption, this paper will then focus specifically on examining the relationship between environmental regulation and innovation in more detail. This paper looks to answer the question: Under what conditions will environmental regulation cause firms to begin choosing to innovate technologically rather than simply to meet regulation with compliance? Using a simple model of price competition between two firms it will be shown that environmental regulation can effectively induce innovation through spending on R&D projects to develop more efficient technology
Thesis (BS) — Boston College, 2010
Submitted to: Boston College. College of Arts and Sciences
Discipline: Economics Honors Program
Discipline: Economics
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Wilkin, Teddy. "Environmental effects on great tit life-histories." Thesis, University of Oxford, 2006. http://ora.ox.ac.uk/objects/uuid:f93e4bc9-4419-4713-b009-08ab98b8d950.
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Explaining variation between individuals is a central concept in ecology. Phenotypic variation is the product of genes, environments and their interactions. In contrast to genotypes which are fixed within individuals, environments vary considerably in time and space and have measurable effects on phenotypic quality between and within individuals. The aim of the current work was to identify environmental sources of life-history variation in a wild population of the great tit. The size of Thiessen polygons formed around c. 8000 nestboxes occupied over a 41 year period was used to estimate breeding density at the level of the individual. Linear mixed modelling showed that birds breeding in large territories laid more eggs and produced heavier fledglings that were more likely to survive to breed, than those in smaller territories. Systematic capping of territory sizes revealed that birds breeding in territories more than 2ha in size were unconstrained by density. This method of measuring individual density identified important relationships between density and life-histories and allowed for the accurate separation of other environmental effects usually confounded by density. For example, the life-histories and breeding density of woodland passerines often both vary with distance from the woodland edge. Using the Thiessen polygons to control for density we were able to independently examine edge effects on life-histories. Results confirmed higher density at edges and independently showed that birds near the woodland edge tended to lay smaller clutches of larger eggs later in the season, than birds away from the edge, probably due differences in habitat quality. A further use of Thiessen polygons was to determine the scale at which to measure oak availability in the vicinity of each occupied nestbox. Birds breeding in oak rich polygons laid larger clutches, earlier in the season and had heavier nestlings than birds in oak poor polygons, independently of density and edge effects. What's more, including oaks in life-history models, reduced or eliminated the effect of the Thiessen polygons, suggesting that density dependent life-histories are to some extent explained by reduced oak availability at high density. Clutch size, fledgling mass and recruitment were also found to correlate with local soil calcium. Analyses performed at several spatial scales found the greatest effect of calcium at scales of c.500m. This figure may indicate the average distance females were travelling to obtain calcium rich food during periods of high demands. That breeding environments strongly affect life-histories has been demonstrated by the above work. However, no correlations were found between natal environment and the subsequent life-histories of recruited individuals, probably due to high mortality in great tits, which favours current condition over any character that conveys benefits later in life. This result shows that long-term effects of rearing environments cannot be assumed as it depends on the life-history conditions under which they are found. The results of this study suggest a pervasive role of fine-scale environment variation in determining the life-histories of individual great tits. Moreover, the study demonstrates the efficacy of GIS to model such variation and applying it to explaining life-history variation in long-term databases.
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Omran, Arthur Phillip Jr. "Bacteriostatic Effects of Sucralose on Environmental Bacteria." UNF Digital Commons, 2013. http://digitalcommons.unf.edu/etd/440.
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Sucralose is a zero calorie sweetener developed and manufactured by Tate and Lyle Sweetener Company in the 1980’s. They sell the sweetener compounded with maltodextrin and dextrose under the brand name Splenda®. Sucralose was developed as a low cost artificial sweetener that is non-metabolizable in humans and can withstand changes in pH and temperature. It is not degraded by the waste water treatment process. Since the molecule can withstand heat, acidification and microbial degradation it is accumulating in the environment, and has been found in waste water, estuaries, rivers and the Gulf Stream. The highest concentration of environmental sucralose detected to date is 300 ng/L (Torres et al., 2009). Our lab has isolated six bacterial species from areas that may have been exposed to sucralose, given that sucralose has been detected throughout the aquatic environment (Mead et al., 2009). These isolates were cultured in the presence of sucralose looking for potential sucralose metabolism or growth acceleration. Sucralose was found to be nonnutritive, and we found bacteriostatic effects on all six isolates. This inhibition was directly proportional to the concentration of sucralose exposure. The amount of the growth inhibition appears to be species specific. The bacteriostatic effect may be due to a decrease in sucrose uptake by bacteria exposed to sucralose. We have determined that sucralose inhibits invertase and sucrose permease. These enzymes cannot catalyze hydrolysis or be effective in transmembrane transport of the sugar substitute. As sucralose builds up in the environment we must consider it a contaminant due to its bacteriostatic effect. Sucralose may also destabilize or shift the compositions of the bacterial communities in microenvironments such as the mammalian gut.
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Westgate, Robert. "Environmental effects on a suspension bridge's performance." Thesis, University of Sheffield, 2012. http://etheses.whiterose.ac.uk/2884/.
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Current Structural Health Monitoring (SHM) research uses changes in a bridge’s behaviour to locate and quantify the damage in a structure. However the structural responses are also linked to environmental effects, such as its temperature and the traffic load. In order to understand a typical suspension bridge’s behaviour to environmental conditions, studies on the Tamar Suspension Bridge’s response to temperature and traffic are contained in this thesis. This was achieved by observing data collected from long-term monitoring systems installed on the structure, and simulated responses derived from a three-dimensional finite element model of the bridge. The data of the bridge have shown that the profile of the suspension bridge reconfigures when the temperature of its structure increases, causing the deck to sag and expand. The natural frequencies of the bridge were noted to drop during the day. Transient thermal responses were also indentified; the differing rates of warming up between the deck, towers and cables manifested in the structural responses of the bridge. Phenomena caused by the temperature differential across the bridge’s surface were also studied. Investigations on the effect of traffic demonstrated its additional mass causes the natural frequencies to decrease for certain modes. This was identifiable in the time series data, where the largest reduction in frequencies is during rush hours. The investigations have shown that the changes the modal frequencies and modal mass are dependent on the eccentricity of the traffic flow on the bridge, which may increase or decrease depending on the mode shape. The loading of an abnormally heavy trailer on the bridge has also demonstrated the deformation to the bridge’s quasi-static shape as the vehicle travelled across. The location of the vehicle on the bridge was also able to affect the modal properties of the suspension bridge, according to simulated results.
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REZAEI, MOHSEN. "Environmental effects on epoxy adhesive and joints." Doctoral thesis, Politecnico di Torino, 2012. http://hdl.handle.net/11583/2497165.
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The use of adhesive joining in mechanical structures, especially in industrial usage, is rapidly
increasing. However, to be confident in their use it is essential to evaluate the performance of the
joints, especially when their strength tends to decrease upon exposure to warm and humid
conditions that cause degradation. Since degradation is a long time process and evaluating the
degradation of adhesive joints in normal condition needs several months or years tests, accelerated
test under controlled environment is unavoidable.
Water can affect both the physical and mechanical properties of the adhesive itself and also the
nature of the interface or interphase that exists between it and the substrate. The aim of this thesis is
considering both aspects, including also other factors that can affect the durability of bonded joints.
To obtain in short time experimental data on the degradation of adhesives exposed to moisture or
immersed in water, a valuable technique is represented by the open-face configuration. Apart from
the acceleration of moisture uptake which is obtained due to the larger area exposed, a further
advantage is the uniformity of degradation. A further acceleration can be obtained by adding a
hygroscopic contaminant at the adhesive/adherend interface, which speeds up moisture uptake and
accentuates the interfacial nature of the failure. The decay of the mechanical strength in absence or
presence of a contaminating agent was evaluated. The effects of a humid and warm environment
and also immersion in water on tensile strength, Young’s modulus and Poisson’s ratio of a twocomponent
epoxy adhesive, Henkel Hysol 3425, were evaluated using bulk specimens,. To relate
the exposure time to the moisture uptake, measurements were performed for both bulk adhesive
specimens and bonded open face joint, in periods of time between 1 and 3 months depending on the
type of test, exposure to warm moisture or immersion in water.
In a further part of the work, the performance of different surface pretreatment techniques of
aluminum open-faced single lap joints was evaluated. Four different surface treatment processes
were tested, namely: Degreasing and Roughening, treating with Picklex 20, Phosphoric Acid
Anodizing (PAA) without and with contamination.
Finally, the effect of warm moisture on the fracture energy of an epoxy-based adhesives was
measured. To evaluate the effect on fracture energy and other related parameters, open-faced double
cantilever beam (DCB) specimens of epoxy-steel adhesive system were exposed to warm moisture,
at 100 % relative humidity and 50 °C.
The methodology introduced in this thesis leads to further investigation on the durability of the
considered adhesive (in terms of joint strength, water uptake measurements, fracture energy, etc)
under different environmental conditions. The methods adopted to accelerate the degradation
process (open face and contamination) revealed an interesting reduction in duration of degradation
process. Surface preparation methods to protect aluminum bonded joints against severe
environmental condition were evaluated and the most suitable one (PAA process) was identified.
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Dijkstra, K. "Understanding healing environments effects of physical environmental stimuli on patients' health and well-being /." Enschede : University of Twente [Host], 2009. http://doc.utwente.nl/60753.
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Song, Danbee. "Effects of the ISO 14001 Voluntary Environmental Program on Economic and Environmental Performance." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1560641816980076.
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Kohn, Christofer. "Centralisation of Distribution Systems and its Environmental Effects." Licentiate thesis, Linköping University, Linköping University, Department of Management and Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2990.
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Many believe that the current application of modern logistics solutions in general and centralisation of distribution systems in particular is damaging from an environmental perspective. The reason for this claim is that when a distribution system is centralised, products need to be shipped over greater distances. This causes an increase in transport work, which in turn is believed to cause an increase in emissions. Further, the decision to centralise distribution can be characterised as a structural decision and earlier research has helped illustrate how such decisions have greater impact on the overall performance of a distribution system than decisions taken at subsequent levels (tactical and operative). The reason for this is that structural decisions help create new opportunities to make other logistical decisions that are beneficial for the performance of a distribution system, as measured in terms of costs and service.
It is also acknowledged that there is a lack of research illustrating the actual environmental effects of centralisation. This area is the theme of this thesis and the overall purpose is to describe and analyse how centralisation of a distribution system can affect the environment. This purpose has been divided into two research questions, where the first one reads:
- How does physical centralisation of a distribution system influence the environment?
This question aims at investigating what effect centralisation has on the amount of emissions that are caused by transport in a distribution system. One of the main advantages with a centralised distribution system is that emergency deliveries are expected to decrease. This type of transport is often performed by airfreight, which is a mode of transport that is regarded to cause the largest amount of environmental stress among the four most commonly used transport modes. The argument that is made is that even though centralisation causes an increase in transport work, this must not necessarily mean that emissions increase.
As indicated above, earlier studies on structural changes in distribution systems have shown that this type of decision creates new opportunities to make other decisions that are beneficial for the performance of a distribution system, albeit in terms of costs and service. The aim of the second research question is consequently to study this issue, but from an environmental perspective. This question therefore reads:
- How do structural decisions in logistics create new opportunities to improve on the environmental performance of a distribution system?
The results of the study show that it is not sufficient to only consider transport work and emergency deliveries when the environmental effect of a centralisation is to be evaluated. It has also been concluded that centralisation creates an opportunity to make improvements within the distribution system that can prove beneficial from an environmental perspective. In summary, three characteristics besides transport work and emergency deliveries were identified as being of importance when considering the environmental effects of a centralisation. These included centralised flow, modal change, and bargaining power.
This model (see full pdf) does not aim to include all characteristics that can be relevant in an environmental evaluation of a centralisation, but rather those that have been found significant in this study. However, the model helps illustrate that there are many aspects that need to be considered in such an evaluation and that depending on the characteristics of the distribution system at hand the results can vary quite extensively.
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Osman, Katarina. "Health effects of environmental lead exposure in children /." Stockholm, 1998. http://diss.kib.ki.se/search/diss.se.cfm?19980529osma.
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Moss, Alison Jeanne. "The effects of applied fields on environmental systems." Thesis, Brunel University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272364.
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Badhe, Renuka. "Effects of polar environmental factors on phytoplankton physiology." Thesis, University of Essex, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.517252.
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Bierbower, Sonya M. "ENVIRONMENTAL EFFECTS ON BEHAVIOR AND PHYSIOLOGY IN CRAYFISH." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_diss/778.
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Despite dramatic morphological differences between animals from different taxa, several important features in organization and sensory system processing are similar across animals. Because of this similarity, a number of different organisms including mammals, insects, and decapod crustaceans serve as valuable model systems for understanding general principles of environmental effects. This research examines intrinsic and extrinsic factors by behaviorally and physiologically means to identify the impact of environmental conditions on two distinct crayfish species- Procambarus clarkii (surface) and Orconectes australis packardi (cave).
The research identified behavioral and physiological responses in these two morphological and genetically distinct species. The studies also examined multiple levels of complexity including social behavior, an autonomic response, chemosensory capabilities and neuronal communication, identified comparative similarities/differences, addressed learning and environmental influences on learning and examined behavioral and cellular responses to high levels of carbon dioxide. I found environmental factors directly influence crayfish behavior of social interactions. Interactions were more aggressive, more intense and more likely to end with a physical confrontation when they took place 'in water' than 'out of water'. The modified social interaction resulted in a altered fighting strategy.
A study on motor task learning was undertaken which showed similar learning trends among these crayfish species despite their reliance on different sensory modalities. I also demonstrated learning was dependent on perceived stress by the organism. Previously trained crayfish inhibited from completing a task showed significant increase in an autonomic stress response.
Studies on the behavioral and physiological responses to CO2 revealed that high [CO2] is a repellent in a concentration dependent manner. The autonomic responses in heart rate and an escape tailflip reflex shows complete cessation with high [CO2]. A mechanistic effect of CO2 is by blocking glutamate receptors at the neuromuscular junction and through inhibition of the motor nerve within the CNS.
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Papathanasiou, Fokion. "Glycoalkaloids in potato tubers : developmental and environmental effects." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361271.
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Stirling, C. M. "Environmental effects in partitioning and development in groundnut." Thesis, University of Nottingham, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233604.
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Pafitis, Demosthenis Georgeou. "Environmental effects on the progressive crushing of composites." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281999.
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Peterson, Kenton W. "Environmental effects on turfgrass growth and water use." Diss., Kansas State University, 2013. http://hdl.handle.net/2097/16222.
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Doctor of PhilosophyDepartment of Horticulture, Forestry, and Recreation Resources
Dale J. Bremer
Jack D. Fry
Researchers and practitioners can use numerous techniques to measure or estimate evapotranspiration (ET) from turfgrass but little is known about how they compare to ET using standard lysimeters. An investigation was conducted to compare measurements of ET from lysimeters (LYS[subscript]E[subscript]T) with ET estimates from the FAO56 Penman-Monteith (PM[subscript]E[subscript]T) and Priestley-Taylor (PT[subscript]E[subscript]T) empirical models, atmometers (AT[subscript]E[subscript]T), eddy covariance (EC[subscript]E[subscript]T), and a canopy stomatal conductance model that estimates transpiration (COND[subscript]T). Methods were compared at the same site during the 2010, 2011, and 2012 growing seasons. Overall, PT[subscript]E[subscript]T and EC[subscript]E[subscript]T were not different from LYS[subscript]E[subscript]T, whereas PM[subscript]E[subscript]T, AT[subscript]E[subscript]T, and COND[subscript]T, increasingly underestimated LYS[subscript]E[subscript]T. Differences exist among ET measurement techniques and one should employ the technique that best fits their situation. An atmometer is an inexpensive tool that can be used to measure turfgrass ET within microclimates, such as those typically found in an urban home lawn. An investigation was conducted to compare AT[subscript]E[subscript]T estimates with PM[subscript]E[subscript]T estimates within a number of lawn microclimates. Home lawns in Manhattan and Wichita, KS, were selected for study during the growing seasons of 2010 and 2011. Open sward AT[subscript]E[subscript]T was 4.73 mm d[superscript]-[superscript]1, whereas PM[subscript]E[subscript]T was 5.48 mm d[superscript]-[superscript]1. Within microclimates, AT[subscript]E[subscript]T was 3.94 mm d[superscript]-[superscript]1 and PM[subscript]E[subscript]T 3.23 mm d[superscript]-[superscript]1. Atmometers can provide practitioners with reliable estimates of PM[subscript]E[subscript]T within microclimates. Zoysiagrass (Zoysia spp.) is a common turfgrass used on home lawns and golf courses. However, poor shade tolerance and cold hardiness have limited its use in the transition zone. A study was conducted to determine changes and differences in growth and physiology among selected Zoysia over a three-year period (2010-2012) in the transition zone. The genotypes were 'Emerald' [Z. japonica × Z. pacifica], 'Zorro' [Z. matrella], 'Meyer' and Chinese Common [Z. japonica], and experimental progeny Exp1 [Z. matrella × Z. japonica], and Exp2 and Exp3 [(Z. japonica × Z. pacifica) × Z. japonica]. 'Zorro' and 'Emerald' experienced winter injury. 'Meyer', Chinese Common, and Exp1 showed poor performance over the three-years. The Exp2 and Exp3 progeny, maintained high percent cover, visual quality, and tiller density, and may provide practitioners more shade-tolerant cultivar choices in the transition zone.
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McNeil, Paul. "Environmental effects on the embryonic development of zebrafish." Thesis, University of the West of Scotland, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.731773.
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Cortese, Luca. "Environmental effects on galaxy evolution in nearby clusters." Aix-Marseille 1, 2005. http://www.theses.fr/2005AIX11018.
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Ce travail est dédié à l'étude des effets d'environnement sur l'évolution des galaxies, en utilisant un échantillon multi-longueur d'onde. En combinant pour la première fois des observations UV de GALEX à des données en optique, et en infrarouge j'ai déterminé l'histoire évolutive des galaxies. Touts les résultats obtenus montrent que : - les elliptiques géantes sont vieilles, à l'inverse des elliptiques naines qui contiennent toujours des populations stellaires jeunes. - L'importance relative des différents mécanismes d'environnement varie avec l'âge de l'univers. Les interactions de marée ont dominé dans l'univers passé mais la pression dynamique domine dans les amas d'aujourd'hui. - La classe des galaxies SO, n'est pas le résultat d'un seul mécanisme de transformation. - Il y a une forte corrélation entre l'âge moyen des populations stellaires et la masse des galaxies. Comprendre l'origine de cet effet représente aujourd'hui un des défis pour les modèles d'évolution des galaxies.
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Hopwood, Paul Edward. "Nutritional and social environmental effects on parental care." Thesis, University of Exeter, 2014. http://hdl.handle.net/10871/15476.
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Parental care is likely to evolve when benefits of care are greater than costs. Provision of parental care may buffer vulnerable offspring against unpredictable or hazardous environments permitting parents to breed in situations too hostile for unassisted juvenile survival. The nature of environmental unpredictability faced by parents and their offspring (e.g., availability of nutritional resources, breeding resources and/or the strength of competition) provides the ecological context in which costs and benefits of parental traits are defined. Therefore investigations about how the environment might shape parental traits ought not only to be conducted in the laboratory but also in a natural setting where unanticipated parameters may have profound effects on theoretical predictions. I conducted a series of manipulative experiments and observational studies in the laboratory and in the field using burying beetles, Nicrophorus vespilloides, to examine the effects of environmental variation on parental competitive ability, reproductive productivity, longevity and the expression of parental sex-role differences and alternative reproductive tactics. In these beetles a relative size advantage confers success in contests for scarce and vital breeding resources so a central prediction was that reproductive success would be positively correlated with body size. In contrast I found that reproductive performance was favoured over contest success when nutritional resources were delayed temporarily during a developmental window. Larger beetles do win contests for breeding-resources but the benefits of being large depend on the quality of the social environment experienced (i.e., the relative size of an opponent). In a naturalistic setting, smaller males avoided direct contests because they attracted proportionately more females and as a result their breeding associations were more often monogamous. This has potential benefits for females because they avoid female-female contests and brood parasitism. Variation in the nutritional environment provided by parents (the carcass size on which offspring are reared) directly influences body size creating a dynamism between the nutritional and social environments experienced by these beetles depending on their size, which has ramifications for their individual success and maintenance of alternative strategies in the population as a whole.
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Melios, Christos. "Graphene metrology : substrate and environmental effects on grapheme." Thesis, University of Surrey, 2017. http://epubs.surrey.ac.uk/845201/.
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Graphene, a single layer of sp2-bonded carbon atoms, has received significant attention due to its exceptional opto-electronic properties and potentially scalable production processes. However, scalable graphene requires an underlying substrate, which is often a source of strain, doping and carrier scattering, limiting the mobility and quality of graphene. It was shown that by intercalating graphene on SiC by hydrogen, the interfacial layer, associated with n-doping and mobility degradation, is de-coupled from the substrate. The transformations of the H2-intercalation were demonstrated using Raman spectroscopy, while the SiC/interface changes were probed using surface enhanced Raman scattering. The H2-intercalation resulted in carrier type inversion, where the decoupled graphene change from n- to p-type, as well as showing mobility enhancement, up to more than four times, compared to as-grown graphene. Using calibrated Kelvin probe force microscopy, local work function maps were generated, demonstrating the changes in local electronic properties with nanoscale resolution. Furthermore, the layer structure, doping and strain induced by the underlying substrate are compared to CVD grown graphene transferred onto Si/SiO2. In addition to the substrate effects, the electronic properties of graphene are also significantly affected due to the direct exposure of π electrons to the environment. For the investigation of the environmental effects on graphene (i.e. H2O and NO2), a custom-built environmental transport properties measurement system was designed and developed, allowing magneto-transport measurements to be conducted in highly controlled environments. Using this system and calibrated local work function mapping, it is demonstrated that water withdraws electrons from graphene on SiC and SiO2 substrates, as well as acting as a source of impurity scattering. However, the sensitivity of graphene to water depends highly on the underlying substrate and substrate-induced doping. Moreover, it is shown that epitaxial graphene can successfully be used as the sensing material with detection down to 10 parts-per-billion molecules. Considering the environmental effects on the electronic properties of graphene, the importance of clearly reporting the measurement environmental conditions is high-lighted, whenever a routine characterisation for carrier concentration and mobility is reported.
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Hewitt, Dominic James. "Probing environmental effects on gas-phase protein structure." Thesis, University of Oxford, 2017. http://ora.ox.ac.uk/objects/uuid:6856e99f-c802-4b96-ba7c-8fc98456f6a0.
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Growth in the use of mass spectrometry as an analytical tool for studying protein structure and functionality has posed questions regarding correlation of native structures and observed gas-phase conformations for proteins. This thesis explores the relationship between the solution-phase and gas-phase structures of soluble proteins, and investigates the effect of the lipid environment on membrane proteins. To assess gas-phase structure, ion-mobility mass spectrometry was used to measure directly the collision cross-sections of soluble proteins across a broad mass range. These collision cross-sections values were then compared with those derived from solution-phase data, calculated from dynamic light scattering experiments. Using computational methods collision cross-sections were calculated from structures reported in the protein data bank using a variety of techniques. Differing physical environments in solution and gas phases are not shown to affect protein structure by the dynamic light scattering and ion-mobility measurements. Contrastingly the computational calculations demonstrate that there is less correspondence between x-ray structures and their gas-phase counterparts. Despite the effect that lipid environment has on membrane protein structure, capturing this native environment has been challenging. Lipodisqs look to overcome this problem by removing the portion of the membrane surrounding the embedded protein. Lipodisqs were investigated as potential vehicles for membrane protein mass spectrometry and compared with conventional detergent based approaches. Lower charge states are observed for proteins released from lipodisqs, compared to those released from detergent micelles, increasing the probability of native features being retained including native-like protein-lipid interactions. Lipodisqs therefore demonstrate significant potential as a tool for membrane protein mass spectrometry. In summary, through this body of experimental work relationships have been established between gas-phase and solution-phase structures as well as computational methods. The use of Lipodisqs to eject membrane proteins from regions of the native membrane has been investigated.
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Elmore, Logan. "Effects of Environmental Water Transfers on Stream Temperatures." DigitalCommons@USU, 2015. https://digitalcommons.usu.edu/etd/4368.
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Low streamflows and warm stream temperatures, caused mainly from agricultural diversions, currently limit available habitat and productivity of trout, including native Lahontan cutthroat trout in Nevada’s Walker River Basin. Environmental water purchases, which transfer water from willing sellers to instream uses (i.e for fish), are being evaluated to improve instream habitat. To determine which environmental water purchases to prioritize, this study was undertaken to build a computer model in order to simulate stream temperatures under differing environmental water transfer scenarios. Model runs simulate a range of environmental water transfers at major diversions and reservoirs throughout the Walker River Basin. Results indicate that low flows generally coincide with critically warm stream temperatures, cooler stream temperatures exist in the East Walker River, a tributary of the Walker River, during warm seasons which provide good habitat for fish, environmental transfers can improve stream temperatures for some highly impacted reaches by up to 3°C in dry years, and environmental water transfers have a greater effect in dry years than wet years.
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Hampel, Regina [Verfasser], and Annette [Akademischer Betreuer] Peters. "Environmental effects and gene-environment interactions : air pollution and temperature effects on cardiovascular risk factors / Regina Hampel. Betreuer: Annette Peters." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2011. http://d-nb.info/1019291494/34.
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Schijf, Bobbi, and n/a. "Assessing the effect of EIA : the influence of environmental effects information on resource consent decision-making in New Zealand." University of Otago. Department of Geography, 2006. http://adt.otago.ac.nz./public/adt-NZDU20070202.121126.
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Environmental impact assessment (EIA) was introduced to inform decision-makers of the potential environmental effects of the decision before them. It has been adopted worldwide and functions as one of the primary instruments for taking account of environmental consequences in project approval decision-making. To date, there has been very little systematic investigation that explores whether the decision-makers for whom the EIA information is produced actually use it, although there are indications that EIA information is not always effective in influencing decisions. This thesis examines how, and indeed if, environmental effects information influences the decision-making processes for which it is produced, and which factors determine the use of this information. Three main areas of concern are identified and investigated: the responses of individual decision-makers to environmental effects information; the characteristics of the effects information that influence these responses; and the processes by which the effects information is dealt with.
At the core of the methodology employed for this research is the development of an exploratory model of EIA-based decision-making. This model builds on the insights into decision processes from a variety of disciplines, including psychology and planning. To test the utility of the model, it is evaluated against the New Zealand system of resource consent approval decision-making under the Resource Management Act, by means of case studies. Through interviews, direct observation, and analysis of written documents the decision processes in these cases are analysed. These techniques have been augmented by psychosocial methods that allow further probing into the decision processes that takes place in a decision-maker�s head.
The research results show that the effort that is spent on the preparation of EIA reports and the improvement of EIA processes is not wasted. The EIA information clearly influences the decision processes for which it is intended but it is not influencing decisions optimally. EIA information often competes with information on environmental effects from other sources that is of higher quality, more credible, or better tailored to the decision-makers� information needs. A number of ways in which the use of EIA information could be enhanced is explored in this thesis. Foremost, the improvement of the effectiveness of EIA requires a wider adoption of a decision-making perspective on EIA, and a broader recognition of the information needs of the different decision processes for which EIA is prepared.
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GARCIA, MARCIA A. A. "caracterizacao radioquimica e impacto radiologico ambiental no processamento de cassiterita para producao de estanho e chumbo metalicos." reponame:Repositório Institucional do IPEN, 2009. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9389.
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Made available in DSpace on 2014-10-09T12:26:26Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T14:04:05Z (GMT). No. of bitstreams: 0
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Ali, A. "The effects of environmental stresses on performance of spring wheat genotypes." Thesis, Bangor University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382246.
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Price-Bishop, G. P., and Phillip R. Scheuerman. "Effects of Starvation on Bacteria." Digital Commons @ East Tennessee State University, 1992. https://dc.etsu.edu/etsu-works/2891.
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Bossley, Jon P. "Environmental Impact from Outdoor/Environmental Education Programs: Effects of Frequent Stream Classes on Aquatic Macroinvertebrates." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1460977372.
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Wharfe, Emma. "An environmental metabolomics investigation of the effects of chiral pharmaceuticals and environmental pollutants on microorganisms." Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/an-environmental-metabolomics-investigation-of-the-effects-of-chiral-pharmaceuticals-and-environmental-pollutants-on-microorganisms(eb1b595d-e44c-47ee-9ad7-865c665579ed).html.
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Active pharmaceutical ingredients (APIs) and their metabolites are ubiquitous in the environment and their occurrence in the aquatic environment is of growing concern. However, despite the fact that these may cause harmful effects in organisms found within this niche, little is currently known about the effects of APIs in the aquatic environment. Chiral pharmaceuticals are of particular concern as the enantiomers may be metabolised differently, with the potential for the production of an array of harmful compounds. There are many racemic APIs for treating human and animal conditions, and even in these target organisms the pharmacodynamic effects of the enantiomers are not always known. Within recent years the importance of the interactions of these compounds within the aquatic environment has been realised and information regarding the fate and biodegradation of such environmental pollutants is of great importance. The advent of post-genomic technologies has proved advantageous in the study of the effects of these environmental pollutants. In this thesis, the effects of a range of chiral APIs, and other environmental pollutants, on environmentally relevant microorganisms were investigated at the metabolome level. The effects of chiral APIs were investigated in a number of prokaryotic and eukaryotic systems in order to provide a comprehensive study of the effects of the APIs in the aquatic environment. FT-IR spectroscopy was employed for metabolic fingerprinting of some environmentally relevant bacteria and GC-MS was subsequently employed for metabolite profiling of two pseudomonads that had shown differential chiral effects with Propranolol. In addition, FT-IR microspectroscopy was employed for the investigation of the phenotypic and localised effects of chiral APIs in a eukaryotic system. Furthermore, the effects of a range of environmental pollutants on a complex bacterial community were investigated with the use of FT-IR spectroscopy and multivariate analysis. Initial results indicated a large phenotypic response in relation to phenol, and this was further explored with a range of ageing experiments and metabolic fingerprinting. An FT-IR peak was found to be characteristic of the phenotypic changes in the actively degrading communities and this was likely to be a degradation product of phenol, and armed with this knowledge the activated sludge community was monitored during the active degradation of phenol with the use of GC-MS.The work presented in this thesis has shown for the first time that metabolomics allows subtle phenotypes in microorganisms to be revealed when they are exposed to chiral forms of APIs which are commonly found in the aquatic environment. Despite these APIs not being designed for any interaction with bacteria and aquatic life in general these are significant findings and may have implications as more and more APIs become detectable and concentrated in the environment due to continued use in man and indeed animals or aquaculture.
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FERRARIO, CLAUDIA. "Emerging contaminants: distribution, environmental fate and effects at different levels of the ecological hierarchy organization." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2018. http://hdl.handle.net/10281/199127.
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Il progetto ha come scopo generale l’incremento delle conoscenze scientifiche relative al destino ambientale di alcuni contaminati emergenti e tradizionali. Lo studio si è concentrato sulla distribuzione e sugli effetti degli inquinanti a diversi livelli della scala gerarchica ecologica.
In particolare è stato studiato il potenziale rilascio dei POP e degli inquinanti emergenti (EC, Emerging Contaminants) dovuto alla fusione dei ghiacciai alpini italiani per evidenziare la presenza di questi composti in un ambiente freddo ad alta quota a seguito dei processi di trasporto atmosferico a scala regionale. L’analisi di campioni di acqua di fusione glaciale raccolti sui ghiacciai alpini ha permesso di notare che la contaminazione degli stessi è dovuta a due processi opposti: da un lato è stata infatti registrata una tendente diminuzione delle concentrazioni dei POP, contrastata però dai processi di accumulo dei EC. Sulla base di questi risultati è stato condotto uno studio sul potenziale di degradazione ad alta quota del clorpirifos (CPF). L'obiettivo è stato quello di descrivere il ruolo della crioconite nell'accumulo di inquinanti organici al fine di includerne il contributo tra i processi di rimozione nei modelli di previsione del destino ambientale di questi composti nelle zone fredde. A tale scopo, è stato condotto un esperimento in situ sul Ghiacciaio dei Forni testando la degradazione del CPF in condizioni di luce e di buio, in ambienti abiotici e biotici. I risultati evidenziano che la biodegradazione contribuisce alla rimozione del CPF dalla superficie del ghiacciaio più significativamente della degradazione fotochimica. Pertanto, la degradazione microbica può contrastare l'accumulo di inquinanti trasportati sui ghiacciai e la loro possibile remissione in ambiente.
Sono stati inoltre studiati i potenziali effetti sub-letali indotti sugli invertebrati acquatici dalle concentrazioni ambientali di ECs. Infatti, attualmente gli effetti ecotossicologici dei composti chimici vengono valutati mediante test di tossicità standardizzati, che trascurano molti processi biochimici e fisiologici in quanto non consentono agli organismi di far fronte ai contaminanti come farebbero in ambiente. Ciò è particolarmente vero a concentrazioni sub-letali poiché questi meccanismi sono funzionali e molti di essi rispondono su scala di giorni. Soprattutto gli effetti non letali, compresi i cambiamenti nel comportamento, potrebbero influenzare la fitness individuale e di conseguenza le dinamiche della popolazione. Evidenze di laboratorio mostrano che l'esposizione a concentrazioni ambientali di diversi EC può causare effetti negativi sugli organismi. Tuttavia è in gran parte sconosciuto come le risposte allo stress chimico si diffondano attraverso i diversi livelli della gerarchia ecologica. Ottenere questo tipo di informazioni sarebbe molto utile per promuovere l'uso dei biomarcatori come indicatori di rischio precoce.
Al fine di comprendere come e se i segnali di stress vengono trasmessi attraverso i livelli gerarchici e la capacità degli endpoint sub-individuali di predire effetti ecologicamente rilevanti, individui di Daphnia magna sono stati esposti a concentrazioni ambientali di CPF e benzoilecgonina (BE). I risultati mostrano che le dafnie esposte a BE e CPF erano in una condizione di stress. È stato inoltre notato che l'attivazione o la non attivazione di alcune attività enzimatiche può portare a diverse modifiche del comportamento del nuoto in D. magna, suggerendo l'esistenza di un legame tra i livelli sub- e sovra-organismo.
Infine, sono state confrontate le risposte comportamentali di dafnia e Diamesa zernyi indotte da diverse diluizioni degli effluenti di depurazione. I risultati ottenuti evidenziano che i campioni di acqua raccolti inducono alterazioni sul comportamento di entrambe le specie.In the present work, the environmental fate of some chemicals in temperate-zone mountain regions and their sub-lethal effects on no-target organisms have been studied to improve knowledge and propose new approaches that would be useful in the risk assessment procedures. In particular, the potential release of legacy POPs and emerging pollutants from the melting of Italian Alpine glaciers is described with the aim of highlighting the presence of these compounds in a remote high-altitude cold site because of Medium Range Atmospheric Transport (MRAT) processes. Two contrasting processes leading to glaciers contamination have been underlined: on one hand, the results suggest a declining trend of POPs while the accumulation of Emerging Contaminants (ECs) in glaciers has been highlighted. Based on these results, a study of the potential degradation of chlorpyrifos (CPF) in a remote high-altitude cold site was performed. The aim is to describe the role of cryoconite in the accumulation of organic pollutants to include its contribution to the removal of organic pollutants in models predicting the environmental fate of these compounds in cold areas. For this purpose, in situ microcosm experiment was carried out on Forni Glacier by testing the degradation of CPF in light and dark conditions, in abiotic and biotic environments. The results highlight that biodegradation contributes to the removal of CPF from the glacier surface more than photochemical degradation. Therefore, microbial degradation can contrast the accumulation of pollutants transported on glaciers and their possible re-emission. The potential sub-lethal effects induced on aquatic invertebrates by environmental concentrations of widespread ECs were investigated. Indeed, currently the ecotoxicological effects of chemical compounds are evaluated by means of standardised toxicity tests, which overcome many biochemical and physiological processes because they do not allow organisms to cope with contaminants as they do in the field. This should be particularly true at sub-lethal concentrations since these mechanisms are functional, and many of them respond on the scale of days. Especially not lethal effects, including changes in behaviour, could affect fitness and consequently population dynamics. These criticalities are particularly true for the ECs, whose adverse effects towards non-target organisms have been only recently highlighted. Moreover, increasing laboratory evidences show that the exposure to environmental concentrations of different ECs may induce several adverse effects to organisms. Nevertheless, it is largely unknown how the responses to chemical stress are spread through the different levels of the ecological hierarchy. Unveiling this kind of information would be very effective for improving the use of biomarkers as early warning indicators of risk. In order to understand how and if the stress signals measured at a given ecological level are transmitted through the other hierarchical levels and the capability of sub-individual endpoints to predict ecologically relevant effects, Daphnia magna individuals were exposed to environmentally relevant concentrations of CPF and benzoylecgonine (BE). The results show that daphnids exposed to environmental levels of BE and CPF were in a condition of stress. In addition, it was noticed that the activation or non-activation in some enzymes activities can lead to different modifications of the swimming behaviour in D. magna, suggesting the existence of a link between sub- and supra-organismal levels. Eventually, the behavioural responses of daphnids and Diamesa zernyi induced by different dilutions of treated sewage effluents were compared. The results obtained highlight that water samples collected induced significant alteration on different swimming behavioural parameters in both species.
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Brierley, Jennifer L. "Thermoregulation and mucosal immunity : the effects of environmental extremes." Thesis, Bangor University, 2013. https://research.bangor.ac.uk/portal/en/theses/thermoregulation-and-mucosal-immunity--the-effects-of-environmental-extremes(d5e98b6d-b1cf-45f7-8b99-bdf16b844c53).html.
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The main objectives of this thesis were to: 1. investigate the effects of acute and chronic hypoxia on human thermoregulation and mucosal inununity, specifically salivary immunoglobulin A (s-IgA) and salivary alpha-amylase during mild cold exposure at rest (Chapter 4 and 5), 2. identify the effectiveness of four practical field re-warming methods for the field treatment of cold casualties on thennoregulation and metabolism (Chapter 6), 3. examine the s-IgA response during and following mild hypothennia (Chapter 7) and 4. detelmine the efficacy of three field protection methods for the prevention of heat loss in non-shivering cold casualties using an ill vitro torso model exposed to - I8.5°C, O°C and 18.5°C for four hours (Chapter 8). Two hours of exposure to a simulated high altitude of 4000m, regardless of hypoxic acclimatisation, did not alter core or mean skin temperature during cold exposure. Nonetheless, hypoxia reduced metabolic heat production which may cause thel1110regulatory implications during longer bouts of cold exposure. Chronic hypoxia reduced thermal sensitivity to the cold which may lead individuals to neglect appropriate behavioural thelmoregulation and increase the risk of local and whole body cold injuries. Given s-IgA responses were unaffected by hypoxia in the cold before and following the 18 day mountaineering expedition suggests individuals are not at risk from URTI upon arrival to altitude. During a three hour ' awaiting rescue ' scenario following cold water immersion to reduce core temperature, a triple layered, metallised survival product with cells to trap heat and self-activating chemical heat pads was more superior at re-warming cold individuals compared to other methods tested. The insulative attribute of this survival bag may reduce possible shivering-induced fatigue and the subsequent increase in heat loss during more prolonged periods of cold exposure (> 4 hours). A reduction in core temperature (≥ 1.5°C) resulting from cold water immersion and subsequent cold air exposure suppressed the usual daily s-IgA response which may increase susceptibility to illness and infection (i.e. URTI, common colds, influenza) if re-warming is not initiated immediately. A non-shivering, in vitro torso model demonstrated that a triple-layered, metallised survival product with cells to trap heat and self-activating chemical heat pads was the most superior of three field cold protection methods to reduce heat loss during exposure to a variety of ambient temperatures (- 18.5°C, O°C and I8.5°C) for four hours. It would appear when individuals experience cold stress at sea level or altitude, a triple-layered, metallised survival product with cells to trap heat and self-activating chemical heat pads may be the optimal light-weight field treatment to counteract the potential onset of hypothennia. For nonshivering casualties, this survival product may greatly reduce heat loss creating a longer survival time while waiting for evacuation to superior medical treatments (e.g. hospitals). The overall aim of this thesis was to clarify the immediate health risks for individuals exposed to the extreme environments of cold and/or hypoxia, and if simple countermeasures which can be easily administered, offer suitable protection in the field to reduce such risks. The key message of this thesis is that individuals exposing themselves to cold and/or hypoxia when un-acclimatised to such conditions should carry self-administering survival bags and follow a specific programme of monitoring thermoregulation and upper respiratory symptoms in order to remain free of illness (e.g. rhinovirus, bronchitis) and peripheral or central cold injury (e.g. hypothermia and frostbite).