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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.
301

Comparisons of modern pollen deposition with vegetation abundance and landscape pattern in NE-Germany / Comparisons of modern pollen deposition with vegetation abundance and landscape pattern in NE-Germany

Matthias, Isabelle 16 July 2014 (has links)
Seit der Einführung der Pollenanalyse für Rekonstruktionen vergangener Vegetationsbedeckung befassen sich Wissenschaftler mit dem Einfluss von unterschiedlichen Pollenproduktionen der verschiedenen Arten sowie der Fragestellung, wie welches Gebiet in den Pollendaten widergespiegelt und interpretiert werden kann. Ziel dieser Arbeit war es den Zusammenhang zwischen Pollen und Vegetation weiter zu untersuchen. Dazu wurden Pollendaten von Oberflächenproben aus Brandenburger Seesedimenten sowie Pollenakkumulationsraten (PAR) von bleidatierten Sedimentkurzkernen mit Vegetationsdaten aus Waldinventurdaten und Biotopkartierungen verglichen. Zu den wichtigen Ergebnissen der vorliegenden Arbeit gehören die Berechnungen von relativen und absoluten Pollenproduktionsraten (PPE und aPPE). Während die PPEs die verhältnismäßige Pollenproduktion der Arten zu einem Referenztaxon beschreiben, ist unter den aPPEs die Pollenproduktion pro Vegetationseinheit, in diesem Fall pro m³ (Biomasse), zu verstehen. Die Ergebnisse zeigen gleich hohe PPE-Werte für Fagus und Pinus und bestätigen im Allgemeinen die PPE-Werte aus Studien, die für andere Regionen Europas erhoben wurden. Die berechneten aPPE-Werte unterscheiden sich dagegen deutlich von den aPPE-Werten in Finnland, wo die aPPE für Pinus um ein zehnfaches geringer ist als in Brandenburg. Dieser Unterschied lässt sich möglicherweise mit einer höheren Nettoprimärproduktion der gleichen Biomasse in Zentraleuropa erklären. Darüber hinaus wurde der Einfluss von Blühalter und Waldstruktur auf PPE Berechnungen evaluiert. Die Ergebnisse zeigen, dass die Berücksichtigung beider Faktoren den größten Einfluss auf die Baumarten hat, die relativ spät den Kronenbereich bzw. ihr Blühalter erreichen, wie z.B. Fagus und Carpinus. Der geringste Einfluss dieser Faktoren zeigt sich für Arten, die bereits nach wenigen Jahren mit der Pollenproduktion beginnen, wie z.B. Betula und Alnus. Für die Berechnung von PPEs und aPPEs muss ein Gebiet um den See (oder das Moor) ermittelt werden, in dem die Pollendaten mit der Vegetation verglichen werden können. Dieses Gebiet für die Berechnung von PPEs wird als „relevant source area of pollen“ (RSAP) bezeichnet. Die RSAP ist definiert als das Gebiet, in dem Pollenprozentdaten und Vegetationsprozentdaten den stärksten Zusammenhang zueinander aufweisen und es zu keiner besseren Korrelation der beiden Variablen in einer weiteren Distanz kommt. Die hier ermittelte RSAP für Brandenburg liegt bei sieben Kilometern und ist damit im Vergleich zu den meisten vorherigen Studien relativ groß. Diese relativ große RSAP lässt sich durch die Quartäre Landschaftsstruktur in Brandenburg erklären, welche durch großräumige Bestände einer Art oder Artenzusammensetzung charakterisiert ist. Des Weiteren zeigen die Ergebnisse dieser Arbeit erstmals, dass PAR für die einzelnen Hauptbaumarten in einem linearen Zusammenhang mit der seeumgebenen Biomasse stehen. Im Gegensatz zu der RSAP ist das Gebiet, welches am stärksten die Variationen der PAR erklärt, relativ klein und erstreckt sich von wenigen Metern bis maximal 2,5 Kilometer vom Seeufer. Die Größe dieses Gebiets variiert zwischen den Arten, was mit der Verbreitung des Pollens und der Abundanz der einzelnen Arten erklärt werden kann. Die Beobachtung, dass der Großteil des Pollens von der nahen Vegetation kommt, bestätigt den Einfluss einer „trunk space“-Komponente eines früheren konzeptuellen Pollenverbreitungsmodells. Die heute genutzten mathematischen Pollenverbreitungsmodelle berücksichtigen diese Komponente jedoch nicht. Nach den Erkenntnissen dieser Studie würde die Berücksichtigung dieser Komponente jedoch zu einer Verbesserung der angewandten Pollenverbreitungsmodelle führen. Die oben genannten Datensätze wurden darüber hinaus für Vergleiche von verschiedenen Pollendiversitätsindexen mit Aspekten der Diversität der Landschaft genutzt. Die Ergebnisse zeigen, dass die Diversität der Pollen zu einem großen Teil mit der Diversität der Landschaft innerhalb eines Kilometers um den See herum erklärt werden kann. Während die nahe Vegetation hauptsächlich die Diversität erklärt, welche sich aus der Anzahl der Arten und deren Abundanz zusammensetzt, ist die „Palynological richness“ von einem größeren Gebiet beeinflusst (sieben Kilometer). Die Gleichverteilung von Pollenkörnen kann somit durch das Verhältnis zwischen der Diversität der Pollen und der „Palynological richness“ beschrieben werden, in dem ein größerer Wert eine größere Gleichverteilung der Arten beschreibt und umgekehrt. Die Ergebnisse dieser Doktorarbeit zeigen, dass die Pollendaten in Abhängigkeit zur Fragestellung ein unterschiedlich großes Einzugsgebiet widerspiegeln. Ein größeres Einzugsgebiet der Pollen wird durch die Komposition der Pollenprozentdaten sowie der Anzahl der Pollentypen beschrieben. Die absolute Abundanz sowie die Diversität der ufernahen Vegetation kann dagegen durch PARs und die Diversität der Pollen interpretiert werden.
302

Strategier för presentationav arbetsprover inom grafiskdesign : hur en arbetssökande grafiskdesigner bäst ”säljer sig själv” tillanställning / Strategies for presenting worksamples in graphic design : how to “sell yourself” to employment as a jobseeking graphic designer

Påls, Helena January 2015 (has links)
För att få drömjobbet inom en konkurrenskraftig bransch som grafiskdesign krävs det lilla extra. Syftet med denna undersökning är att ta redapå vad detta extra är och därigenom underlätta för arbetssökandegrafiska designers på vägen till drömjobbet.Genom tre djupgående intervjuer med anställda på medelstora byråer iMellansverige undersöktes vad arbetsgivare uppskattar och förväntar sigav en arbetssökande grafisk designer. Frågeställningen behandladeportfolions framtid med branschens digitalisering som bakgrund, samthur en arbetssökande fångar arbetsgivarens intresse.Resultatet visar att även om portfolion utgör en stor del av underlaget förrekrytering av personal, är personen bakom portfolion och vad den haratt berätta om innehållet det som är viktigast. En portfolio som intebeskriver sammanhang duger inte som marknadsföringsmaterial. Attvårda det personliga varumärket framstår som viktigt för framgång. Dendigitala portfolion dominerar marknaden, men fysiska arbetsproverupplevs som ett möjligt sätt att stå ut från mängden. Digitala nätverkmottas positivt av branschen, men webbplatser anses ha mer substans. / To get the job of your dreams in a competitive industry like graphicdesign you need that special something. The purpose of this survey is tofind out what that something is and thereby make it easier for jobseeking graphic designers on the road to their dream job.Through three in-depth interviews with employees at medium-sizedfirms in central Sweden investigations were made to find out what theemployers appreciate and expect from a job seeking graphic designer.The issues treated were the role of the portfolio with the industry'sdigitization as a background, and how a job seeker captures theemployer's interest.The results show that although the portfolio represents a large part of thebasis in recruitment of staff, the person behind the portfolio and what ithas to tell about the content is the most important. A portfolio that doesnot describe the context is no good as promotional material. To take careof the personal brand stands out as important to succeed. The digitalportfolio dominates the market, but physical work samples are seen as apossible way to stand out from the crowd. Digital networks arepositively received by the industry, but personal websites are consideredto have more substance.
303

Development of Capillary Electrophoresis Methods Coupled to Mass Spectrometry for Biomedical and Pharmaceutical Analysis

Elhamili, Anisa January 2011 (has links)
The analysis of large intact proteins and complex biological samples containing drug molecules is a common complicated task for many scientists. However, due to the importance of these molecules, there is a growing interest in pharmaceutical and medicinal research to develop rapid, highly sensitive and efficient analytical techniques. The advantages of capillary electrophoresis (CE) in combination with mass spectrometry (MS) provide a powerful analytical tool. However, further improvement and development of these techniques are required to extend their utility and to meet the challenges of selected analytes. Thus, the scope of this thesis deals with the development of novel analytical methods to achieve efficient and high performance analysis of peptides, intact proteins, digests of complex samples and basic pharmaceutical drug compounds in biological matrices. Implementation of CE for routine analysis of proteins and complex samples is constrained by the partial adsorption to the capillary wall. Consequently, the use of surface modified capillaries is required to control the surface properties and prevent analyte adsorption. In this thesis, analyte adsorption was successfully prevented using tailored covalent cationic (M7C4I) and electrostatic cationic (PVPy-Me) coatings. Rapid and efficient separations of peptides, proteins and digests of complex samples such as cerebrospinal fluids were obtained with these coatings. The M7C4I coating showed a distinct ability to handle large intact proteins with a molecular size of over 0.5 MDa. The highest peak efficiencies and surprisingly high peak stacking effects were obtained by adding salts to the protein samples. The effect of salt additives on peak efficiencies of intact proteins was further demonstrated and compared using different surface modified capillaries. Additionally, rapid CE-ESI-MS quantification of pharmaceutical drug molecules in human plasma was performed after a SCX-SPE sample preparation method using the M7C4I coating. In conclusion, the results presented in this thesis show the strong potential of CE in combination with MS using electrospray ionization (ESI) for the analysis of peptides and large intact proteins and the applicability for clinical monitoring of the levels of pharmaceutical drug molecules in human plasma with high sensitivity and efficiency. / Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 734
304

Šešupės tvenkinio Marijampolėje aplinkosauginės būklės pagerinimas / Improvement of the environmental condition of the Šešupė pond in Marijampolė

Nagrockienė, Erika 21 June 2013 (has links)
Magistro baigiamojo darbo tikslas – išanalizuoti Šešupės tvenkinio būklės situaciją ir būklės gerinimo kryptis, bei ištirti investicinių projektų galimybes vandens telkinio būklei pagerinti. Šiame darbe yra nagrinėjama Šešupės tvenkinio aplinkosauginė būklė ir tiriamos investicinių projektų galimybės Šešupės tvenkinio būklei pagerinti. Tyrimai atlikti Šešupės tvenkinyje 2012 metais gegužės ir spalio mėn. Imti mėginiai vandens tyrimams iš trijų skirtingų vietų ir išanalizuoti aplinkotyros laboratorijoje. Atliekant vandens cheminės būklės tyrimus analizuoti šie vandens būklės rodikliai: PO-P4, Skendinčios medžiagos, Permanganato indeksas, Pb, pH, O2, N-NH4, N-NO2, N-NO3, Nb, BDS7. Tyrimams panaudoti duomenys gauti prieš tvenkinio tvarkymą ir prasidėjus rekonstrukcijai. Tyrimų metu nustatyta, kad vandens cheminė būklė ženkliai nepakito. Didžiausi vandens cheminės būklės pakitimai rasti nustatant bendrą azotą, kuris parodo vandens būklės pablogėjimą. Išaiškintos priežastys, dėl kurių atsirado vandens cheminės būklės pakitimai. Taip pat buvo nagrinėjamas geriausio scenarijaus pasirinkimas alternatyvų analizės būdu. Šiame projekte geriausias sprendimas pasirenkamas atlikus daugiakriterinę alternatyvų analizę. / The aim of this master's final paper is to analyze the condition of the Šešupė pond and the directions for improvement of this condition and also to study the possibility to implement investment projects for improvement of the condition of the pond. This paper analyzes the environmental condition of the Šešupė pond and studies the possibility to implement investment projects for improvement of the condition of the Šešupė pond. Analyses were conducted in the Šešupė pond during the period from May to October 2012. Water samples for the analyses were collected at three different places of the pond and analyzed in an environmental science laboratory. The analysis of water chemical status included the following water status indicators: PO-P4, materials in suspension, permanganate index, Pb, pH, O2, N-NH4, N-NO2, N-NO3, Nb, BDS7. Data used for the analyses were obtained before reconstruction of the pond and at the beginning of reconstruction. The analysis has shown that the water chemical status has not changed significantly. The most significant changes of the water chemical status were found during the analysis of total nitrogen which is the indicator of water status deterioration. The reasons of the changes of the water chemical status were clarified. Also I have studied the selection of the best scenario through the analysis of the alternatives. The best solution in this project is selected after multi-criteria analysis of the alternatives.
305

Survival of infectious agents and detection of their resistance and virulence factors

Tano, Eva January 2015 (has links)
In the first study, three different transport systems for bacteria were evaluated. The CLSI M40-A guideline was used to monitor the maintenance of both mono- and polymicrobial samples during a simulated transportation at room temperature that lasted 0-48 h. All systems were able to maintain the viability of all organisms for 24 h, but none of them could support all tested species after 48 h.  The most difficult species to recover was Neisseria gonorrhoeae, and in polymicrobial samples overgrowth was an observed problem. The aim of the second study was to study the presence of TSST-1 and three other important toxin genes in invasive isolates of Staphylococcus aureus collected during the years 2000-2012 at two tertiary hospitals. The genes encoding the staphylococcal toxins were detected by PCR, and whole-genome sequencing was used for analyzing the genetic relatedness between isolates. The results showed that the most common toxin was TSST-1, and isolates positive for this toxin exhibited a clear clonality independent of year and hospital. The typical patient was a male aged 55-74 years and with a bone or a joint infection. The third study was a clinical study of the effect of silver-based wound dressings on the bacterial flora in chronic leg ulcers. Phenotypic and genetic silver-resistance were investigated before and after topical silver treatment, by determining the silver nitrate MICs and by detecting sil genes with PCR. The silver-based dressings had a limited effect on primary wound pathogens, and the activity of silver nitrate on S. aureus was mainly bacteriostatic. A silver-resistant Enterobacter cloacae strain was identified after only three weeks of treatment, and cephalosporin-resistant members of the Enterobacteriaceae family were relatively prone to developed silver-resistance after silver exposure in vitro. The last study was undertaken in order to develop an easy-to-use method for simulating the laundering process of hospital textiles, and apply the method when evaluating the decontaminating efficacy of two different washing temperatures. The laundering process took place at professional laundries, and Enterococcus faecium was used as a bioindicator. The results showed that a lowering of the washing temperature from 70°C to 60°C did not affect the decontamination efficacy; the washing cycle alone reduced the number of bacteria with 3-5 log10 CFU, whereas the following tumble drying reduced the bacterial numbers with another 3-4 log10 CFU, yielding the same final result independent of the washing temperature. To ensure that sufficient textile hygiene is maintained, the whole laundering process needs to be monitored. The general conclusion is that all developmental work in the bacterial field requires time and a large strain collection.
306

On Fuzzy Bayesian Inference

Frühwirth-Schnatter, Sylvia January 1990 (has links) (PDF)
In the paper at hand we apply it to Bayesian statistics to obtain "Fuzzy Bayesian Inference". In the subsequent sections we will discuss a fuzzy valued likelihood function, Bayes' theorem for both fuzzy data and fuzzy priors, a fuzzy Bayes' estimator, fuzzy predictive densities and distributions, and fuzzy H.P.D .-Regions. (author's abstract) / Series: Forschungsberichte / Institut für Statistik
307

La riqueza léxica en la producción escrita de estudiantes suecos de ELE / Lexical richness in Swedish students' written production in Spanish as a foreign language

Berton, Marco January 2014 (has links)
Los estudios sobre riqueza léxica con participantes suecos tienen, en su gran mayoría, la L2 inglés como lengua objeto. A día de hoy, no se conocen investigaciones que tengan como lengua objeto el español. Respecto a los participantes, suelen ser estudiantes con un nivel de competencia alto. El presente estudio se centra en la L3 español y estudiantes de nivel bajo e intermedio. En concreto, las muestras de lengua analizadas son narrativas escritas por 180 estudiantes suecos de bachillerato, elicitadas a través de una serie de viñetas. De acuerdo con las dos preguntas de investigación, este trabajo tiene como objetivo principal arrojar luz sobre la relación entre diversidad léxica y competencia léxica y morfosintáctica en la L3 español. En segundo lugar, se comparan varias medidas de diversidad léxica en busca de una medida apta para discriminar de una manera fiable entre diferentes niveles de competencia en la lengua meta. Los datos demuestran un efecto tangible del nivel de competencia sobre la diversidad léxica, aunque de las comparaciones que resultan ser estadísticamente significativas se manifiesta una fuerte influencia del factor edad. Respecto a las medidas, el Índice de Guiraud y el indicador Carroll son las únicas que discriminan significativamente entre los participantes más jóvenes, y también resultan idóneas a discriminar en dos comparaciones del grupo más mayor. Por consiguiente, se consideran las medidas más fiables entre las que se han utilizado en el estudio. Sin embargo, los resultados estadísticos de las dos medidas coinciden a tal punto que se puede afirmar que se trata de dos versiones de la misma medida, aunque muestran valores numéricos diferentes. / Research on lexical richness with Swedish subjects have mostly English as a target language. At the present time, we cannot find investigations having Spanish as a target language. Subjects are usually university students with high proficiency. This study focuses on Spanish as a third language and students with low/intermediate proficiency. Language samples consist of 180 narratives written by Swedish high-school students with a low/intermediate average proficiency in Spanish. The samples have been elicited by means of pictures. According to the two research questions, the main aim of the present study is investigating the relationship between lexical diversity and lexical and morphosyntactic proficiency in Spanish as a third language. Secondly, we compare several measures of lexical diversity searching for results that can reliably discriminate between different proficiency levels in Spanish. The data show a clear effect of proficiency on lexical diversity, even though statistically significant comparisons also point out the influence of the age factor. Regarding the measures, Guiraud’s Index and Carroll’s indicator are the only ones that significantly discriminate among younger participants. They have also proved to be suitable for discriminating comparisons within the older participants’ group. Nevertheless, the statistical results of these two measures correspond to such a high degree that we can consider them as two versions of the same measure, even if they provide different numerical values.
308

Characterization of Bacterial Community Structure in Deep Subsurface Sedimentary Core Samples from Michigan Basin, Ontario

Ilin, Dimitri 10 January 2012 (has links)
Deep subsurface rock samples from Upper Ordovician strata in the Michigan Basin were analyzed for the presence of microbial communities. High concentrations of biogenic methane were observed in the Upper and Middle Ordovician formations. Total porosity values for the shale, shale hard bed and limestone samples were 7.4%, 2.5% and 1.9%, respectively. Hydrocarbon presence ranged from petroliferous shale, to bituminous layering in shale hard beds, to hydrocarbon odour in limestone. Organic carbon content ranged from 0.5 to 2.5%, highest amount being present in the shale. Environmental DNA was extracted from core samples and PCR amplified using 16S rDNA bacterial primers. PCR performed with archaeal 16S rDNA and methanogen-specific (mcrA) primers did not yield DNA amplification. Gene analysis indicated that bacterial sequences similar to Proteobacteria, Cyanobacteria, Firmicutes, and Actinobacteria were present. Most sequences were not related to known cultivated species. Proteobacteria was the most dominant phyla at all depths and included heterotrophic, lithotrophic, acidophilic, radiotolerant, and sulphate-reducing species of bacteria. This study concludes that the observed biogenic methane is a product of ancient methanogenesis.
309

Inventario de radionuclideos artificiais em agua do mar e sedimentos da costa sul do Brasil

FIGUEIRA, RUBENS C.L. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:19Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:12Z (GMT). No. of bitstreams: 1 06901.pdf: 9310315 bytes, checksum: 34ec97737bf373b58a295f330b6aa935 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
310

Determinação de cobre, ferro, níquel e zinco em matrizes tanólicas por espectrometria de fluorescência de raios-x com energia dispersiva após pré-concentração em papel cromatográfico

Santos, Elenir Souza January 2012 (has links)
122 f. / Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2013-03-22T17:20:17Z No. of bitstreams: 1 Tese corrigida final.pdf: 1322795 bytes, checksum: a277616fb5634d49040e3b569eae8dd2 (MD5) / Approved for entry into archive by Ana Hilda Fonseca(anahilda@ufba.br) on 2013-06-05T17:38:45Z (GMT) No. of bitstreams: 1 Tese corrigida final.pdf: 1322795 bytes, checksum: a277616fb5634d49040e3b569eae8dd2 (MD5) / Made available in DSpace on 2013-06-05T17:38:45Z (GMT). No. of bitstreams: 1 Tese corrigida final.pdf: 1322795 bytes, checksum: a277616fb5634d49040e3b569eae8dd2 (MD5) Previous issue date: 2012 / CAPES / No presente trabalho, desenvolveu-se um método alternativo para determinação de cobre, ferro, níquel e zinco, usando a espectrometria de fluorescência de raios-X com energia dispersiva (EDXRF), em amostras de etanol combustível e cachaça, após procedimento de pré-concentração. O procedimento consistiu na retenção dos analitos em papel cromatográfico de troca iônica, suporte sólido que se mostrou apropriado para medições diretas por EDXRF. Algumas variáveis foram otimizadas e os melhores resultados obtidos foram: vazão de amostragem de 2,0 mL min-1, pH entre 5,0 e 7,5 e volume de amostragem de 10 mL. No procedimento, com auxílio de uma bomba peristáltica, alíquotas da solução padrão ou amostra foram passadas em papel cromatográfico de troca catiônica, que foi cortado em círculos com 13 mm de diâmetro e adaptados em suporte para filtração. Após a secagem dos papéis cromatográficos, foram realizadas medições diretas no papel empregando espectrômetro de fluorescência de raios-x de energia dispersiva. As curvas de calibração apresentaram resposta linear no intervalo de 0,050 a 1,50 μg mL-1 dos analitos. As repetibilidades, expressas em termos de RSD das soluções-padrão contendo 0,25 μg mL-1 de Cu, Fe, Ni e Zn, calculadas a partir de 15 determinações consecutivas, foram de 2,5, 2,8, 3,0 e 2,7%; e 3,1, 2,9, 2,8 e 2,7%, para matrizes com 96% e 50% de etanol, respectivamente. Obteve-se limites de quantificação (LQ) iguais a 43, 50, 50 e 40; e 47, 54, 59 e 45 μg mL-1, para matrizes com 96% e 50% de etanol, respectivamente. O procedimento foi verificado através de testes de recuperação, adicionando-se 100 μg L-1 de cada metal nas diferentes amostras, com resultados entre 92 e 99%. Os resultados obtidos pelo método proposto foram comparados com os resultados obtidos por um método comparativo usando ICP OES, após digestão das amostras, não apresentando diferenças significativas, com um nível de confiança de 95%. O método proposto é simples e não exigiu que as amostras fossem submetidas a qualquer pré-tratamento drástico ou demorado. / Salvador

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