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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Fate of pharmaceuticals in the environment - A review-

Kalyva, Maria January 2017 (has links)
The occurrence of pharmaceuticals in environment originating from human consumption has received increased scientific attention during the last decades due to concerns regarding their combined environmental effects in aquatic and terrestrial environments, in flora and biota and by extent in human health. In this review, I summarized the existing knowledge on the entire life cycle of pharmaceutical substances, from their exposure (sources) and fate to their effects on the natural environment. Since the negative effects of several drugs along with the environmental damage they entail are now known, it can be suggested that pharmaceutical companies make greener pharmaceutical products to reduce these effects to the terrestrial and aquatic environment. The present review could provide suggestions to improve the pharmaceutical environmental management globally, such as methodologies for monitoring systems, that need to be put in place for consistent data collection. Another area of research that is important is the release of pharmaceutical compounds in manufacturing plants as well as from landfill effluent. Finally, one more area with need for further research is green chemistry which could reduce or even eliminate the potential hazards of pharmaceutical compounds that enter the environment, irrespective to the source of entry.
12

Plavání osob s tělesným postižením - charakteristika současného stavu v ČR a VB / Swimming for the physically handicapped - characteristic of the present state in Czech Republic and Great Britain

Kantorová, Lucie January 2012 (has links)
Goals: The main aim is to map and characterize current situation of The swimming for the physically disabled in Czech Republic and Great Britain. To provide information about the identity or difference of working with swimmers with physical disabilities in both countries, in terms of content, organizational, safety and personnel. To draw conclusions and to propose possible changes and recommendations for optimization and improvement of the state while swimming with people with disabilities in Czech Republic based on these information. Methods: The method of quality, analysis and subsequent synthesis, comparative method, visiting activities and observations have been used. Information was drawn from Czech and foreign literature, as well as from Czech and foreign web sites. Some facilities were visited personally, the others were contacted throughout the internet. Results: This work focuses on content of the methods used for swimming of the persons with disabilities in both countries and compares them, further evaluate and compare the swimming centers in both countries according to set criteria. The criteria that should be meet by the coach who works with physically disabled swimmers can be learned in this diploma, and are also valid for both countries. The work introduces the various organizations,...
13

The role of shelter in cherax abidus and bidyanus bidyanus polyculture systems

Wangpen, Prayadt January 2007 (has links)
Research into the polyculture of finfish and crayfish has been conducted in Western Australia for over a decade now. This research was instigated out of a need to increase revenues from freshwater crayfish farmers wishing to diversify their income base with a view to increasing profitability and reducing risk. It has become clear that several key variables dictate how the polyculture system (i.e. polysystem) will perform. These include biological factors like: size of participating species, relative densities, gender, planktonic turbidity, natural feeds; and abiotic factors like: light intensity, clay turbidity, floating cages for segregation, water quality, and habitat/shelter complexity. Many of these factors can be controlled / adjusted by the manager of the polysystem to maximise performance, production and profitability.While much of the research to date has focussed on the marron (Cherax tenuimanus) industry, it is also important to realise that an understanding of these factors can also assist other crayfish polysystems, like integrated agri-aquaculture systems containing yabbies (Cherax albidus). Some of the factors that influence how the system will perform may become more prevalent, like suspended clay turbidity and the associated role of light intensity in species interactions, or shelter complexity and the resulting choice of shelter material. But overall, they are the same basic variables and we must understand how they affect the particular multi-species system that we are dealing with. There is a lot to be learned from the literature on how these variables affect multi-species aquatic environments in the wild. Perhaps aquaculturists have not considered this enough in the past. Some farmers seem to believe that these variables are different JUST because it is a culture system. This is not true. / The variables will take on different levels in a culture system (i.e. a manager will stimulate turbidity, provide artificial feeds, stock different sizes, and supply particular types of shelter) BUT the actual variables themselves (e.g. food, density, light, shelter) are basic to ALL aquatic ecosystems. Other researchers have looked at important factors like density, gender, and light intensity / turbidity in crayfish polysystems - but the issue of habitat complexity and the role of shelter has not been adequately addressed. This thesis will investigate some basic questions about shelter and endeavour to apply them to crayfish polysystems, with the emphasis on marron (C. tenuimanus) and yabbies (C. albidus) because these are the two most commercially important species of crayfish in Western Australia. Importantly, it should be noted that due to the invasive nature of yabbies, and their apparent ability to displace native marron in the wild, findings will be related to yabby-marron competition / displacement where relevant. We need to know many things about shelter: what type is best in a multi-species system? Should the shelter size match the crayfish size? Do marron have different requirements for shelter than yabbies? Does it matter who gets first use of a shelter (i.e. prior residence effect)? Can we learn about crayfish shelter requirements by examining the behaviour / plasticity of crayfish species? If crayfish are stocked with finfish and they retreat into shelter as a predator-avoidance measure, is the complexity important given that their densities will be higher? If densities of crayfish inside shelters are higher in polysystems, will cannibalism be a concern, particularly when conditions are right for moulting? Does visual recognition and / or chemo-detection of a predator affect the shelter usage by marron or yabbies? / Does temperature affect shelter usage behaviour for a burrowing species like yabbies? Shelter is an important factor in the life history of a freshwater crayfish and an understanding of its influence on different species is important for maximising system performance. Crayfish are categorised depending on their ability to construct shelters (i.e. burrows). Yabbies have evolved in systems with fluctuating water quality and many predators and, as such, have learned to burrow (to escape drought and also to escape predators). Marron, on the other hand, are a non-burrowing native crayfish species that have existed with relatively few predators in the South-West. As a result, marron are less capable of modifying their behaviour when confronted with a predator (i.e. low behavioural plasticity). Species with high plasticity, like yabbies, are more capable of adapting to new environments, because they can change their behaviour to increase their chance of survival. Therefore we can expect yabbies and marron to utilize habitats differently and we should compare these behaviours as a basis to developing management strategies. This type of knowledge may also assist with managing the translocation and spread of yabbies in the wild and their displacement of native marron.Within multi-species systems, the physical structure of shelter plays an important role inprotecting crayfish and the perfect shelter would not only provide safety from co-stocked finfish, but also from conspecific cannibalism. Given the different life histories and behaviours, it is probable that both species of crayfish will have different refuge requirements.Over the course of this four-year investigation, trials were conducted in four culture systems (72L aquariums, 300L circular tanks, 80t mesocosm tank, and 720m2 earthen ponds) using marron and yabbies as the species of interest. / Silver perch and Murray cod were chosen as the finfish species of interest as they appear to have the highest aquaculture potential for native freshwater finfish in Australia at the present time. Further, both of these fish have been documented as potential predators of crayfish, resulting in a challenge to understand the role of shelter in minimising the negative effects of fish-crayfish interactions within a polysystem. This study has confirmed that shelter plays a critical role in multi-species system dynamics. In the case of polysystems, it will affect both interspecific and intra-specific interactions, ultimately governing production and profitability, along with the other, previously defined factors. This means that the manager of a polysystem can influenceproductivity by understanding: a) the behavioural characteristics and biology of the crayfish; b) the feeding biology of the finfish; and c) the system variables (both biotic and abiotic) that will affect the overall well being of the fish and crayfish. In the case ofshelter, the manager should understand the available shelter types, the appropriatedensities, the importance of matching complexity to the crayfish size, and the prior residence effect when choosing a timing strategy for stocking and harvesting. Prior residence increased resource holding potential for both marron and yabbies in the short term. In fact, prior residence was a stronger determinant of successful sheltering than crayfish gender or species. However, in longer-term trials the physical size of the crayfish (larger animals evicted smaller animals) and reproductive status (berried females were successful at evicting all other crayfish) were more important factors in determining successful shelter acquisition, although the temporal variations (i.e. growth and release of young) complicate the issue. / When stocking crayfish of different sizes, and in polysystems, the correct size of shelter becomes critical, as smaller individuals will be forced to leave over-sized shelter and locate a shelter commensurate with their own body size to avoid predators. This is relevant to crayfish nurseries where complex habitat is paramount for juvenile cohorts that display variation in sizes and gender. The expansion of crayfish polyculture holds considerable promise; however, furtherinvestigations are required into shelter complexity within floating fish cages, shelter types and arrangement of shelters within ponds (for increased production and ease-of-harvesting), potential of yabbies in polyculture (comparison of monosex and hybrid strains), and the impact of shelter on escape behaviour of marron in a polysystem.
14

Transformation and Fate of Nanoscale ZnO, Ag, and CeO2 in Different Aquatic Environments

Sung, Wen-Ting 05 March 2012 (has links)
The fate and transformation of laboratory-prepared nano-ZnO, nano-Ag and nano-CeO2 in three aqueous solutions under different environmental conditions were investigated in this work. Over the past decades nanomaterials have been widely used in different technical fields and consumer goods. As a result, nanomaterials might enter the environmental media via different routes and then posed potential hazards to the environment and human health. Researches in this regard have received much attention worldwide. In this work it was found that the solubility of each nanomaterial was highly influenced by the solution pH, but not by the solution temperature. The maximal solubility for the tested nanomaterials was obtained at pH 3, namely about 100% for nano-ZnO and lower than 2% for both nano-Ag and nano-CeO2. The solution pH and ionic strength were found to affect the stability of nanoparticles in different aquatic environments. For the solution pH of higher than the isoelectric point of the concerned nanomaterial, the higher the solution pH is, the greater the degree of stabilization of nanoparticles would be. On the contrary, nanoparticles aggregated as the ionic strength of the solution exceeded its critical aggregation concentration (CAC). CAC for each concerned nanomaterial could also be graphically determined as the attachment efficiency (£\) of nanoparticles increased with increasing ionic strength of the solution and then leveled off after reaching CAC. Experimental results also showed that Zn(OH)2(s) would form when nano-ZnO was in the solution of pH 10. The crystalline structure of the said precipitates was confirmed by X-ray diffraction. Likewise, Ce4+ dissolved from nano-CeO2 reacted with SO42- in aqueous solution yielding Ce(SO4)2(s). Clearly, transformation of nanomaterials might take place when they are in contact with various species in different aquatic environments. Humic acid in aqueous solution was found to be beneficial to the stability of nanomaterial of concern. Efforts have also been made to study the reaction behaviors among di(2-ethylhexyl)phthalate, erythromycin, and selected nanomaterials when they co-existed in the same solution. Their interactions, however, seemed to be unobvious. In this work it was found that under sunlight irradiation nano-ZnO did show its antibiotic effect due to photocatalysis. Nano-Ag was proven to have a strong antibacterial ability even in natural aquatic environments. It yielded the total bacteria survival ratio of less than 2% within one hour of reaction. In summary, the findings of this study showed that the behaviors of nano-ZnO, nano-Ag, and nano-CeO2 in aqueous solutions could be greatly influenced by different factors in different reaction systems.
15

An evaluation of the environmental fate of reactive dyes

Hetheridge, Malcolm John January 2001 (has links)
Dyestuffs are widely used industrial chemicals, yet surprisingly little is known about their fate in the environment. The potential modes of transformation and removal of reactive dyes in treatment and in the environment are principally through anaerobic and aerobic biodegradation and photodegradation. The research herein describes the use of LC-MS analysis with laboratory simulations to develop a better understanding of the occurrence and fate of reactive dyes and their degradation products in the aquatic environment. One reason for the lack of information on the environmental fate of reactive dyes has been the paucity of robust analytical methods suitable for the determination of dyes in aqueous samples. Robust analytical methods were optimised to provide LC-MS and MSMS identification of degradation products. Additionally, interpretation of the MSMS spectra of known reactive dyes provided novel characteristic fragment ions indicative of the triazine reactive group of reactive dyes . Fibre reactive dyes are designed to have a degree of photostability and therefore their photodegradation behaviour has not been widely investigated. Little is known of their stability to daylight over prolonged periods of irradiation in dilute aqueous solutions and in the presence of humic substances. The kinetics of photodegradation of an anthraquinone dye (Reactive Blue H4R) and azo dye (Reactive Yellow P5G) were evaluated. The former underwent rapid and extensive degradation 01/2 1.5 h). The major products formed were identified using LC-MSMS and a photodegradation pathway proposed. By comparison, the photodegradation of the azo dye was significantly slower, 01/2 30 h). The addition of humic substancesa ppearedt o have little effect on the rate of photodegradationu nder the conditions used. The reduction of azo dyes under anaerobic treatment has been extensively studied, but the subsequent fate of the initial reduction products when exposed to air are not understood. Three relatively simple azo dyes, Amaranth, Sunset Yellow and Naphthol Blue-Black, were reduced and their autoxidation products identified by LC-MS. These were subsequently used to predict the autoxidation products of a more complex azo reactive dye: Reactive Red 3.1. Additionally, a persistent degradation product from the anaerobicaerobic treatment of Reactive Red 3.1 was identified from LC-MS data. Azo reactive dyes are generally regarded as being resistant to aerobic degradation and there are few published data regarding degradation pathways for reactive anthraquinone dyes. Pure cultures of Pseudomonas docunhae, A 9046 and A texaco and mixed bacterial consortia (semi-continuous activated sludge, SCAS) aerobic degradation of azo and anthraquinone reactive dyes was studied. Two azo dyes were degraded by pure cultures of A docunhae and A 9046, suggesting that azo dyes can be aerobically degraded given favourable conditions. The antraquinone dye was extensively degraded by SCAS and pure culture biodegradation. Metabolites were identified by LC-MS and a degradation pathway proposed.
16

Spatiotemporal variability of chemistry and biota in boreal surface waters : a multiscale analysis of patterns and processes /

Stendera, Sonja, January 2005 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 4 uppsatser.
17

Studies on Plesiomonas shigelloides isolated from different environments /

González-Rey, Carlos, January 2003 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 5 uppsatser.
18

Fish and amphibians as test organisms for evaluation of effects caused by chemicals /

Carlsson, Gunnar, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 5 uppsatser.
19

Metodologia de avaliação de risco ecológico em ambiente aquático a partir de evidências químicas, biológicas e ecotoxicológicas

Tallini, Karin January 2010 (has links)
A contribuição deste trabalho é apresentar uma metodologia de avaliação de risco ecológico do ambiente aquático utilizando-se dados provenientes de programas de monitoramento ambiental. O estudo tem como cenário um trecho do Rio Jacuí, município de São Jerônimo – RS, Brasil, que foi avaliado através da aplicação de um programa de monitoramento ambiental. Consideraram-se como variável explicativa deste estudo, as evidências registradas nos compartimentos abióticos, água superficial e sedimento. As evidências químicas foram decorrentes da presença dos metais Hg, Pb e Zn e as evidências ecotoxicológicas de ensaios de toxicidade aquática com Ceriodaphinia dubia para água superficial e Hyalella azteca para sedimento. Consideraram-se como variáveis respostas as evidências biológicas compostas pelos dados de riqueza, índice de Shannon-Weaver, equitatividade e densidade numérica das espécies das comunidades zooplantônica e bentônica. O risco ecológico (Baixo, Médio e Alto) foi caracterizado pela associação à qualidade ambiental (Ótima, Alerta e Crítica), respectivamente, estabelecida pelas evidências registradas. Os resultados permitem considerar que é possível o uso de programas de monitoramento ambiental para avaliação de risco ecológico, se contiverem, além dos dados químicos e ecotoxicológicos exigidos pela legislação ambiental, dados do monitoramento da biota residente. / The contribution of this work is to present a methodology for ecological risk assessment in an aquatic environment using data derived from environmental monitoring programs. The location focused by this study was a segment of the Jacuí River, in the town of São Jerônimo – RS, Brazil, which was assessed by applying an environmental monitoring program. The evidence recorded from the abiotic compartments surface water and sediments was considered an explanatory variable. The chemical evidence stemmed from the presence of Hg, Pb and Zn, while the ecotoxicological evidence resulted from aquatic toxicity tests using Ceriodaphinia dubia for surface water and Hyalella azteca for sediments. The biological evidence from the Shannon-Weaver index, species richness, equitability and numerical density data in zooplanktonic and benthonic communities was considered the response variable. The ecological risk (Low, Medium, and High) was characterized by the association with environmental quality (Great, Warning, and Critical), established by the evidence recorded. The results have shown that it is possible to use environmental monitoring programs to evaluate of ecological risk assessment, if they have chemical and ecotoxicological data required by environmental laws, and monitoring data of resident biota.
20

Características biomecânicas de idosas caminhando em ambiente terrestre e aquático em piscina rasa e em piscina funda / Biomechanical characteristics of elderly women walking on land and in aquatic environment in shallow and deep water

Silva, Eduardo Marczwski da January 2009 (has links)
Embora a prática de atividade física tenha se tornado comum em ambiente aquático, ainda há pouca informação a respeito das características biomecânicas da caminhada de idosos nesse ambiente. No intuito de investigar essas características, o objetivo do presente estudo foi comparar parâmetros cinemáticos (lineares e angulares) e eletromiográficos de idosas caminhando em ambiente terrestre (TE) e em ambiente aquático em piscina rasa (PR) e em piscina funda (PF). Doze mulheres idosas saudáveis foram avaliadas enquanto caminhavam em uma intensidade de esforço auto-selecionada (confortável) na terra e na água em PR e PF (imersas ao nível do processo xifóide). Variáveis cinemáticas e eletromiográficas foram registradas. Comparada às outras duas modalidades, em PF as idosas apresentaram menor velocidade, menor comprimento de passada e duração do período de apoio durante a caminhada. Ainda, os indivíduos caminharam com o tronco mais inclinado a frente e com maior amplitude de movimento (ADM) do quadril e do joelho. Essas alterações cinemáticas foram associadas a maior atividade dos músculos eretor da coluna (EC), bíceps femoral (BF) e reto femoral (RF). Por outro lado, a atividade do músculo gastrocnêmio (GAS) foi inferior a encontrada em TE. Já em PR, as idosas caminharam com menor velocidade, menor comprimento de passada e duração do período de apoio comparado a caminhada em TE. A ADM do joelho também foi menor em PR. Ainda, a atividade do músculo BF foi superior durante o período de apoio, bem como do músculo RF durante o período de balanço. Em contrapartida, a atividade do músculo GAS foi inferior durante o período de apoio. Em uma mesma intensidade de esforço auto-selecionada (confortável) os indivíduos caminharam mais lentamente em ambiente aquático. Nessa condição, a necessidade de superar a grande resistência oferecida ao movimento e à ausência de contato do pé com o solo caracterizaram a caminhada em PF como um exercício de grande ADM do quadril e do joelho, grande exigência dos músculos EC, BF e RF e pequena exigência do GAS. Por sua vez, a necessidade de superar a grande resistência oferecida ao movimento associado ao reduzido peso hidrostático caracterizaram a caminhada em PR como um exercício de pequena ADM do joelho, grande exigência dos músculos BF e RF e pequena exigência do GAS em idosos. Esses resultados contribuirão para um melhor entendimento acerca das características apresentadas por idosos caminhando em PF e PR sendo de grande auxilio na elaboração de programas de treinamento e reabilitação para essa população. / Although water environment has been employed for different physical activities, there is little information about biomechanical characteristics of elderly walking at shallow and deep water. With the purpose to investigate these characteristics, the mean of the present study was to compare kinematics (linear end angular) and electromyographic patterns of elderly individuals walking on land (LW), in shallow (SWW) and deep water (DWW). Twelve healthy elderly women were analyzed while walking at self-selected pace (moderate) on land and in water (at the xiphoid process level). Kinematic and electromyographic variables were registered. Compared to LW and SWW, during DWW elderly women presented the slowest speed, the shortest stride length and support phase duration. Individuals walked with trunk at the most forward inclined position, as well with the largest hip and knee joints range of motion (ROM). This kinematic changes were related to the highest erector spinae (ES), biceps femoris (BF) and rectus femoris (RF) muscles activity. On other hand, gastrocnemius medialis (GM) activity was lower than during TE situation. During SWW, elderly women walked at slower speed, shorter stride length and support phase period when compared to LW. The knee ROM was also lower. However, BF muscle activity was higher during stance period as well as RF activity during swing phase. In opposition, GAS muscle activity was lower during stance phase. At the same self-selected pace (moderate) elderly women walked slower in aquatic environment. In this condition, the necessity to move against the drag force without feet contact from the bottom of the swimming pool described the DWW walking as an exercise performed with large hip and knee ROM, high stimulation of ES, BF and RF muscles and low stimulation of GM muscle. In other way, the necessity to move against the drag force associated to the apparent body weight reduction described the SWW as an exercise performed with short knee ROM, high stimulation of BF and RF muscles and low stimulation of GM muscle in elderly women. The present results will contribute to a better understanding about elderly walking characteristics in shallow and deep water, being useful for training and rehabilitation programs designed by these population.

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