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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.
181

Faror på förskolan : En studie om förskolepersonalens kunskaper och arbete gällande miljögifter inom förskolan / Hazards at preschool : A study of preschool staff's knowledge and work about environmental toxins in preschool

Faleij, LOUISE January 2015 (has links)
Vi utsätts dagligen för en mängd kemikalier, vissa av dem är skadliga både för människan och miljö. För att uppnå det svenska miljökvalitetsmålet giftfri miljö är det av yttersta vikt att förskolorna måste bli giftfria, detta då många förskolor har produkter och leksaker som innehåller miljöfarliga ämnen. Barn är känsligare än vuxna och det är därför av stor betydels att fasa ut produkter från förskolorna där barnen vistas många timmar om dagen. Flertalet kommuner har starta detta arbete men det är viktigt att det sker en beteendeförändring för att åstadkomma ett hållbart resultat. Syftet med studien var att undersöka om information till förskolepersonalen har bidragit till ökad kunskap om miljöfarliga kemikalier på förskolan. Studien syftar även att undersöka om ökad kunskap har lett till ett förändringsarbete samt vilka hinder och möjligheter som finns för att använda kunskapen i ett arbete för giftfri förskola. Det görs med hjälp av att både enkätundersökning och intervjuer hos förskolepersonal verksamma inom Karlstad kommun. Undersökningen som gjordes visar att det finns en positiv attityd hos förskolepersonalen för att jobba vidare med att fasa ut miljögifter på förskolan. Den visar även att medvetenheten och kunskaperna hos förskolepersonalen är goda då de har kännedom om produkter samt ämnen som bör undvikas inom förskolan. Flertalet hinder finns för att personalen ska kunna arbeta på ett effektivt sätt med att minska skadliga ämnen inom förskolorna. Det som begränsar personalens handlingsutrymme är bland annat ekonomi, bristfällig kunskap, tid, oro, upphandlingsavtal och utbud.  För att målet giftfri miljö skall kunna uppnås behöver stödet förbättras för förskolepersonalen. Detta kan göras genom bland annat vidareutbildning och uppdatering av personalen, hårdare krav på upphandling och andra hjälpmedel för att val av bättre produkter ska underlättas och en giftfri förskola ska bli möjliga. / In todays world we’re exposed daily to a large amount of chemicals, some of which are harmful to man and the environment. To reach to objective of a toxic free environment it is of uttermost importance that our preschools become free from toxins, especially since there today exist several products and toys that contain hazardous substances. Kids are more sensitive to these compared to adults which is why the importance of clearing them out from the preschools are even more important, especially since the kids spend several hours a day there. Several municipalities has begun this task though it is also important for a behavioral change to happen if the result is to be sustainable. The purpose of the study was to examine if information to the stuff of the preschools has contributed to an increased knowledge about hazardous substances in preschools.  The surveys purpose is also to examine if an increased knowledge has led to an improvement as well as which obstacles and possibilities exist for the usage of this knowledge in working for a toxin-free preschool. This will be done through a survey and interviews with preschool staff who are active within Karlstad municipality. The survey showed of a positive attitude in the preschool staff concerning continuing the work to phase out hazardous substances from their preschools. Their awareness and knowledge are at a good level since they have knowledge about what products and substances to avoid in preschools. Several obstacles that hinder the staff from working effectively at decreasing the amount of hazardous substances at preschools. Things which limits the staff are economics, lack of knowledge, time, anxiety, procurement terms and range among others. For the objective of a toxic free environment to be reached the support of the preschool staff needs to be improved. This can be accomplish through  tougher terms of procurement, more support and education of the staff among other things to help them make better choices of products which in turn will make a toxic free preschool a possibility.
182

Oleander Poisoning of Livestock

Wilson, F. W. 15 April 1909 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
183

Μελέτη της τύχης της ζιζανιοκτόνου ουσίας πεντιμεθαλίνης (pendimethalin) σε εδαφικούς και υδάτινους αποδέκτες

Παπαγεωργίου, Σταματίνα 10 March 2009 (has links)
Σκοπός της παρούσας διπλωματικής εργασίας είναι η μελέτη της τύχης της ζιζανιοκτόνου ουσίας Πεντιμεθαλίνης σε εδαφικούς και υδάτινους αποδέκτες. Η τύχη των φυτοφαρμάκων στο φυσικό περιβάλλον αποτελεί μια άκρως ενδιαφέρουσα μελέτη. Η έρευνα της προσρόφησης των οργανικών ουσιών στο έδαφος αποσκοπεί στον υπολογισμό των συγκεντρώσεων που βρίσκονται στο χώμα μετά την αποκατάσταση της ισορροπίας, αλλά και πως αυτές διαφοροποιούνται αλλάζοντας σε συνάρτηση με το pH και την ιοντική ισχύ. Καθοριστικό ρόλο στην μελέτη της τύχης των φυτοφαρμάκων στους εδαφικούς αποδέκτες, παίζουν οι μηχανισμοί ρόφησης, η σύσταση του εδάφους καθώς και οι φυσικοχημικές ιδιότητες του εδάφους και των φυτοφαρμάκων. Από την άλλη πλευρά, οι ποσότητες που καταλήγουν στο νερό, λαμβάνοντας υπόψη τη δοσολογία χρήσης των φυτοφαρμάκων, φανερώνουν πόσο σημαντικοί είναι οι παράγοντες που επηρεάζουν τη μεταφορά μέρους των φυτοφαρμάκων στα επιφανειακά νερά, για την εκτίμηση της τύχης τους στους υδάτινους αποδέκτες. Η προσροφητική ικανότητα της Πεντιμεθαλίνης στους τέσσερις τύπους εδαφών που μελετήθηκαν με διαφορετικά φυσικοχημικά χαρακτηριστικά μειώνεται καθώς μειώνεται και η περιεκτικότητα τους σε οργανική ύλη. Τα πειραματικά δεδομένα, που προέκυψαν από τη μελέτη της προσρόφησης του ζιζανιοκτόνου στους τέσσερις τύπους εδαφών, προσαρμόζονται σε κάθε περίπτωση πολύ καλά στην λογαριθμική εξίσωση Freundlich, όπως φαίνεται από τον υψηλό συντελεστή συσχετίσεως. Η αλλαγή του pH του συστήματος εδάφους-νερού δεν έχει πολύ σημαντική επίπτωση στην προσρόφηση της Πεντιμεθαλίνης από τη στιγμή που το τελευταίο δεν είναι ιονιζόμενη ένωση. Αύξηση της ιοντικής ισχύος είχε ως αποτέλεσμα την αύξηση της προσρόφησης της Πεντιμεθαλίνης. Η Πεντιμεθαλίνη ανιχνεύτηκε σε υδατικά δείγματα ποταμού, ο οποίος διέρχεται μέσα από καλλιεργήσιμες εκτάσεις σε μέγιστη συγκέντρωση 40 ng/l σε σύντομο χρονικό διάστημα μετά την εφαρμογή του στο έδαφος. / -
184

International Workshop on Advanced Techniques in Actinide Spectroscopy (ATAS 2012) - Abstract Book

Foerstendorf, H., Steudtner, R. 08 May 2013 (has links) (PDF)
Modern Societies have to consider diverse tasks strongly related to geochemistry sciences. Examples intensively discussed in the public are restoration measures for contaminated industrial fallow grounds, the safe storage of chemical-toxic and radioactive waste, carbon dioxide sequestration to reduce green-house gas emissions, the construction and operation of deep geothermal power plants, the geochemical exploration of natural resources or water and waste water treatments, including desalination efforts. Direct and urgent aspects to be dealt with are analytical and geochemical consequences of the Fukushima Daiichi nuclear disaster. All these cases have one in common – they require reliable thermodynamic data in order to forecast the fate of chemicals in the respective environment. Whereas a variety of standard methods, such as potentiometry, solubility studies, liquid-liquid extraction or electrochemical titrations, are in widespread use to generate thermodynamic data, it is far less straightforward to assign correct reaction pathways and structural patterns to the underlying chemical transformations. This especially holds for systems with strong tendencies to complexation and oligomerization. Here, it is essential to have proof of evidence for all involved species, which cannot be provided by the aforementioned methods, and is still lacking for various metal-containing systems. Spectroscopic techniques in combination with approaches from quantum chemistry can be of great benefit for such tasks. However, their application ranges are often restricted with respect to the type of element (and redox state) that can be probed. Further handicaps are imposed by detection limits or other parameters such as pH or salinity. Moreover, the spectroscopic results are often difficult to interpret in an unambiguous way. To overcome these complications at least partially, this workshop has been initiated. It shall significantly extend the application areas of spectroscopic tools important for lanthanide and actinide chemistry. Emphasis shall be placed on the development of spectroscopic methods towards more challenging environmental conditions – such as very basic pH values, elevated temperatures, pressures, or salinities – extending the range of covered elements and redox states. Furthermore, the exploration of options for lowering detection limits and increasing spatial resolution at sufficiently high signal-to-noise ratios will support future investigations on more complex systems. An approach combining the extension of spectroscopic tools with respect to elements and parameters, improvements of experimental setups, and applications of quantum chemical methods in predictive as well as interpretative ways certainly can be very beneficial. The workshop hopefully will bundle and strengthen respective research activities and ideally act as a nucleus for an international network, closely collaborating with international partners. I am confident that the workshop will deliver many exciting ideas, promote scientific discussions, stimulate new developments and in such a way be successful.
185

Naftos ir naftos ploviklio Simple Green bendras toksinis poveikis vaivorykštiniam upėtakiui ankstyvoje ontogenezėje / The toxic effects of crude oil combined with oil cleaner "simple green" on rainbow trout in ontogenesis

Ratkelytė, Eglė 08 September 2009 (has links)
NAFTOS IR NAFTOS PLOVIKLIO SIMPLE GREEN BENDRAS TOKSINIS POVEIKIS VAIVORYKŠTINIAM UPĖTAKIUI ANKSTYVOJE ONTOGENEZĖJE E. Ratkelytė Vilniaus universitetas Santrauka Tyrimai buvo atlikti su vaivorykštinio upėtakio (Oncorhynchus mykiss) ikrais (nuo „akutės“ stadijos) ir lervomis (nuo jų išsiritimo pradžios iki trynio maišelio rezorbcijos), veikiant juos 0,11, 0,22, 0,43, 0,87, 1,73, 3,46, 6,93 g/l naftos koncentracijomis į kiekvieną iš jų pridedant 0,5 g/l ploviklio Simple Green. Toksiškumo kriterijai buvo upėtakio ikrų ir lervų žuvimo procentas, ir tokie fiziologiniai rodikliai, kaip širdies (ŠD) bei kvėpavimo (KD) dažniai. Darbo tikslas buvo ištirti naftos ir naftos ploviklio Simple Green bendrą toksinį poveikį vaivorykštiniam upėtakiui (Oncorhynchus mykiss) ankstyvose jo vystymosi stadijose priklausomai nuo koncentracijos ir poveikio trukmės bei įvertinti ilgalaikio poveikio fiziologiniams rodikliams ypatumus. Apibendrinus gautus rezultatus galima teigti, kad vaivorykštinio upėtakio jautrumas naftos ir ploviklio Simple Green mišiniui priklauso nuo mišiniu veikiamos individo vystymosi stadijos, poveikio trukmės, ir naftos bei ploviklio koncentracijų santykio mišinyje. Nustatyta, kad jautriausios naftos poveikiui pasirodė lervutės ritimosi metu, mažiau jautrūs pasirodė embrionai ankstyvoje „akutės“ stadijoje. Palyginus gautus rezultatus su rezultatais gautais tiriant vien tik naftos poveikį vaivorykštiniam upėtakiui ankstyvoje ontogenezėje, matome, kad ploviklis Simple Green... [toliau žr. visą tekstą] / THE TOXIC EFFECT OF CRUDE OIL COMBINED WITH OIL CLEANER „SIMPLE GREEN“ ON RAINBOW TROUT IN EARLY ONTOGENESIS E. Ratkelytė Vilnius University Summary Long-term effects of crude oil combined with oil cleaner „Simple Green“ were evaluated in chronic toxicity tests by use of rainbow trout (Oncorhynchus mykiss) in early stages of development (embryos, larvae) as test-objects. The following toxicity criteria were studied for evaluation of toxic effects: mortality of embryos and larvae; physiological parameters (heart rate, ventilation frequency). The aim of the study was to investigate the overall effect of crude oil combined with oil cleaner „Simple Green“ on rainbow trout (Oncorhynchus mykiss) in early development stages (embryos, larvae) depending on oil concentration in the mixture and exposure duration and to evaluate the specificity of negative effects of mixture on physiological parameters of fish. It was determined that 0.87, 1.73, 3.46 and 6.93 g/l concentrations of crude oil combined with 0.5 g/l of “Simple Green” resulted in the significant increase in larvae mortality, but practically had no negative effect on embryos. Hatching was found to be the most sensitive stage of development, 1 day age larvae were less and embryos were the least sensitive to the toxic impact of mixture, respectively. It was estimated that 0.87+0.5, 1.73+0.5, 3.46+0.5 and 6.93+0.5 g/l concentrations of crude oil combined with oil cleaner „Simple Green“ disturbed the work of cardiorespiratory... [to full text]
186

Exploring and Evaluating Veterinary Team Effectiveness in Companion Animal Practice

Moore, Irene C 15 May 2013 (has links)
The veterinary healthcare team concept was explored using an inductive approach involving four veterinarian (N=23) and four Registered Veterinary Technician focus groups (N=26). Themes revealed included Communication, Toxic Attitude and Environment, Leadership, Coordination, and Work Engagement. Each was subsequently explored in a study of team effectiveness and its associations with job satisfaction and burnout. A random sample of 274 participants from 48 companion-animal veterinary teams was recruited. Mixed linear regression found job satisfaction increased with increased individual engagement and tenure at the practice, and decreased with increased years in veterinary medicine, full-time employment status, or within a toxic clinic environment. Higher scores for exhaustion and cynicism were associated with the presence of a toxic environment, reduced individual engagement, and full-time employment status. A coordinated team environment contributed to decreased cynicism and increased professional efficacy scores. These results suggest team effectiveness significantly influences job satisfaction and burnout among veterinary healthcare teams. / Royal Canin Veterinary Diets
187

Deviation from predictions in corporate environmental performance: antecedents and financial consequences

Walker, Kent 17 January 2011 (has links)
This dissertation examines two main research questions: Why do firms deviate from their predicted level of toxic emissions, and how do these differences relate to financial performance? The objective is threefold: (1) to understand deviation in corporate environmental performance by looking at both industry and firm level variables, (2) to see how this deviation relates to both profitability and fluctuations in financial performance, and (3) to see if, and how, corporate environmental legitimacy affects the relationship between corporate environmental deviation and corporate financial performance. To achieve this objective the construct “corporate environmental performance deviation” is developed. It is defined as the extent to which a firm’s environmental performance deviates from its predicted performance, and is used to capture within-firm strategic choices in environmental management. Predicted environmental performance is calculated based on certain firm characteristics such as size and industry. Actual environmental performance is calculated using a weighted score of air emissions obtained from the Toxic Release Inventory (TRI) database. The difference between these two values represents a corporation’s environmental performance deviation. Corporate environmental performance deviation focuses on strategic choices related to environmental management, while recognizing that environmental management is the result of both institutional pressures and within-firm strategic decisions. Aligned with this focus, variables 2 related to this strategic choice are used to explain deviation in environmental management, including an environmental integration capability, firm strategy, and industry munificence and dynamism. Associated with the internal and external organizational analysis, institutional theory and the resource-based view (RBV) are used to explore the tension between deviation to increase competitiveness versus isomorphism to attain legitimacy. The sample is composed of 311 U.S. firms who have reported their toxic air releases to the TRI from 1998-2007. The sample is broken down into two subsets, those that exceed (positive deviation) or fail to meet (negative deviation) predicted environmental performance. Results of a longitudinal analysis show that positive environmental deviation is related to a greater capacity to strategically integrate environmental issues into a firm’s existing business approach, less munificence and dynamism in the task environment, and reduced financial fluctuations. Negative environmental deviation is decreased through a demonstrated capacity to strategically integrate environmental issues into a firm’s existing strategic approach, and related to greater munificence and dynamism in the task environment, reduced profitability and increased financial fluctuations. Lastly, although there are no significant main effects for corporate environmental legitimacy, the paradoxical combination of negative deviation and environmental legitimacy can reduce the severity of the negative financial results to negative deviation, both in terms of profitability and financial fluctuations.
188

Inorganic Heavy Metals as Environmental Pollution Indicators in Rio Baru, Costa Rica

Metzger, Lia Kimiko 01 January 2015 (has links)
Pollution from industrial sources, such as leather tanneries, jewelry factories, car batteries, and construction refuse, has been linked to increased concentrations of toxic heavy metals in rivers in Costa Rica. This study focused on the concentrations of arsenic, cadmium, chromium, copper, nickel, and lead in sediment and water in Rio Baru, Costa Rica, which has not been previously studied. The concentrations in Rio Baru were compared to two controls and the Environmental Protection Agency toxicity limits to determine pollution levels. Inductively coupled plasma mass spectrometry was utilized to determine the concentrations of heavy metals in water and sediment samples from Rio Baru, Terciopelo, and Rio Tarcoles. Watershed analysis for Rio Baru was expected to reveal mostly agricultural sources of contaminants. Rio Baru was predicted to have levels of inorganic heavy metals between Rio Tarcoles and Terciopelo, with Tarcoles containing the highest levels. As, Cr, and Ni in Rio Baru were between unpolluted levels in Terciopelo and polluted levels in Rio Tarcoles, but Rio Baru had lower concentrations of Cu and Pb than both Rio Tarcoles and Terciopelo. Analysis of watersheds determined that Rio Baru’s watershed contained intermediate ratios of human development and agricultural sources of pollution. Further comparisons of watershed size with total dissolved sediment levels found a positive linear relationship, indicating a portion of differences in heavy metal concentrations were due to watershed sizes. Concentrations of heavy metals in Rio Baru’s water were below toxic limits for drinking water and placed Rio Baru within “good” sediment levels for As, Cd, Cr, Ni, and Pb. As geochemistry and proximity to industrial sources was not accounted for in methodology, further research would be necessary for determination of natural concentrations of heavy metals in Rio Baru.
189

Preventing Toxic Behaviour through Game Mechanics

Fahlström, Josefine, Matson, Emma January 2014 (has links)
Toxic Behaviour, the phenomena where a person behaves in a way meant to intimidate or belittle another person, is an influential issue spreading across the virtual spaces that is online gaming communities. In this thesis we explore the possible correlations between Toxic Behaviour and game mechanics in online multi-player games by analyzing League of Legends (Riot Games, 2009), one of the most prominent online games currently dominating the market (Statista, 2014). We have analysed the game using a contemporary design framework used in the game industry accompanied by an ethnographical field study of the regular player base of League of Legends we have determined the most common reasons behind why these players tend to engage in Toxic Behaviour and if those reasons are connected to the game’s mechanics. Finally, we conceptualize plausible solutions based on our findings that hypothetically could decrease the amount of toxic player’s continuing engagement in Toxic Behaviour.
190

Förutsättningar för hantering av kemikalierisker i förskolor : En fallstudie av Haninge kommun

Ashja, Maryam January 2014 (has links)
Goods that children come in contact with on a daily basis for example toys, electronics, textiles, household items, have attracted an increased attention in recent years because of a common occurrence of residues of potentially hazardous chemical substances. Some municipalities in Stockholm have developed plans for managing chemical risks and work systematically to phase out products containing hazardous substances. This thesis aims to contribute to an improved knowledge base for any future work with non-toxic nursery schools in Haninge. The study's focus is on the challenges encountered by conditions and problems of preschool personnel to manage chemical risks in early childhood environments. Primary data was collected through a qualitative approach based on semi-structured interviews with both the preschool staff and practitioners working in the central organization of the municipality. Identified key scientific studies and theories related to the concepts of risk management, risk perception and risk communication were used to put the results of the study in a larger context. A thematic analysis was then performed using developed indicators of effective risk management related to, for example, risk perception, accountability and internal and external risk communication. The results from this study show that most of the indicators of effective risk management are not met in the current situation. For example, the communication failure and pre-school staff's discretion is limited by budget, procurement contracts and imperfect knowledge while there is no routine monitoring work to follow up requirements associated with procurement. Haninge municipality can improve the pre-school staff conditions including setting higher standards in procurement, focus on communication and information, be clearer in its guidelines on hazardous chemicals in children's everyday lives and develop follow-up work around the requirements.

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