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Nitrogen Fixation in Lakes: Response to Micronutrients and Exploration of a Novel Method of MeasurementSchmidt, Bethany Marie, Ms. 23 April 2018 (has links)
No description available.
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En jämförelse mellan två immunokemiska metoder vid analys av NT-proBNP i plasmaNyqvist, Hannes January 2016 (has links)
NT-proBNP is a biproduct derived from the synthesis of BNP, a synthesis stimulated when cardiomyocytes are stretched such as in heart failure. Heart failure is defined as the hearts inability to supply the blood volume the body acquires. It is advantageous to monitor changes for adequate treatment. NT-proBNP has proven to be an excellent marker for this purpose. The purpose of the study was to compare the two immunochemical methods for measuring NT-proBNP: Roche Elecsys proBNP II analyzed with Cobas e601 and Siemens IMMULITE 2000 NT-proBNP analyzed with IMMULITE 2000 XPi. For this comparison 60 lithium heparin plasma samples from 36 men (60 – 90 years old) and 24 women (65 – 94 years old) was used. IMMULITE 2000 XPi served as the reference method. Results from the assays were compared in a correlation diagram, which indicated good correlation (R: 0.98). Cobas e601 yielded results on average 17.4 % lower than the reference method. A paired t test was used to prove significant diference at 95 % confidence level between the methods on a 95 % confidence level. Precision regarding Roche Elecsys proBNP II, based on measurings of plasma with low and high analyte concentration, 25 replicates one day and 5 replicates 4 days gave imprecisions <3 % (CV%). Reference method imprecision (CV%) <5 % was calculated from control analysis. Good correlation between the two methods and lower imprecision when using proBNP II indicate that Cobas e601 can be used. / NT-proBNP är en restprodukt vid syntes av brain natriuretic peptide (BNP), vars syntes stimuleras av att hjärtats myocyter töjs ut såsom vid hjärtsvikt. Hjärtsvikt innebär att hjärtat inte orkar pumpa den volym blod som motsvarar systemkretsloppets behov. Det är fördelaktigt att kunna följa förändringar i hjärtmuskelns funktion för adekvat behandling. NT-proBNP har visat sig vara en bra markör i detta syfte. Studiens syfte var att jämföra två immunokemiska metoder: Roches Elecsys proBNP II i analysinstrumentet Cobas e601 med Siemens IMMULITE 2000 NT-proBNP i analysinstrumentet IMMULITE 2000 XPi. Studiematerialet kom att bestå av 60 patientprover av litiumheparinplasma från 36 män (60 – 90 år) samt 24 kvinnor (65 - 94 år). IMMULITE 2000 Xpi fungerade som referensmetod. Resultat av kalibrering överensstämde med erhållna masterkurvor och analys av kontroller gav resultat inom 1 SD. Analysresultaten från de båda metoderna jämfördes i ett korrelationsdiagram. Spridningsdiagrammen indikerade en korrelation om R: 0,98. Jämförd metod gav dock i genomsnitt 17,8 % lägre resultat. Signifikant skillnad metoderna emellan vid 95 % konfidensnivå påvisades genom ett parat t-test. Precision avseende Roches Elecsys proBNP II undersöktes genom analys av plasma med hög respektive låg analytkoncentration (25 replikat samma dag och 5 replikat om dagen i ytterligare 4 dagar) vilket totalt gav en imprecision om <3 % uttryckt i CV. Referensmetodens imprecision beräknades utifrån analyserade kontroller och gav en CV <5 %. God korrelation mellan de båda metoderna samt lägre imprecision vid användning av Elecys proBNP II talar för att den jämförda metoden kan tas i bruk.
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Evaluation of CellaVision DM1200 Vet and its ability to differentiate feline leukocytes compared to manual differential count and Advia 2120Andersson, Vidar January 2016 (has links)
Leukocyte differential count in peripheral blood smear has, ever since the method was developed more than 100 years ago, been one of the most frequently used diagnostics tool in the routine hematology laboratory. The manual differential count of leukocytes using a microscope is still the standard method in most small and medium sized laboratories. Even though the method does not require any expensive instruments it comes at a high cost due to it being labor intensive and time consuming. In recent years the rapid technical advancements has led to the development of automatic or semi-automatic methods in which the leukocytes are differentiated. In this study a method comparison was made between manual leukocyte differential counts, CellaVision DM1200 Vet and Advia 2120 when analyzing 106 fresh, feline blood samples. The general agreement between results was good, especially for the most common leukocytes, such as neutrophils and lymphocytes. Results for eosinophils and monocytes had moderate agreement. The confidence intervals were generally wider when CellaVision DM1200 Vet was compared with Advia 2120, than when CellaVision DM1200 Vet was compared to the manual differential count. Despite the fact that Advia 2120 and CellaVision DM1200 Vet are both faster and often show comparable results to the manual differential count, the light microscopy will remain the gold standard for difficult samples, where there is suspicion of inflammation (band neutrophils), intracellular microorganisms, reactive lymphocytes or if the sample contains a high degree of smudge cells or artifacts.
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Verifiering av procalcitonin på instrumentet ADVIA Centaur XPT / Verification of procalcitonin on the instrument ADVIA Centaur XPTMalm, Beatrice January 2020 (has links)
Bakgrund och syfte Procalcitonin (PCT) används i sjukvården vid uppföljning av patienter med bakterieinfektion. Under rådande corona-pandemi har studier visat att förhöjt PCT är associerat med utvecklingen av en svår form av Sars-Cov2-infektion. Genom att mäta PCT kan tecken till sekundär bakterieinfektion identifieras och utvecklingen av svår sjukdomsbild förutspås.På Universitetssjukhuset Örebro (USÖ) sker analysen av PCT på instrumentet Cobas e411. Under den pågående pandemin pågår det nu diskussion kring att överföra PCT-analysen till instrumenten ADVIA Centaur XPT på USÖ istället eftersom detta instrument även finns i Lindesberg och Karlskoga. Analysen skulle därmed kunna ske på alla tre laboratorier. Metod Venöst blod med olika koncentrationer av PCT samlades in från 21 patienter. Proverna användes till patientjämförelse. Till inomserieprecision användes patientprover som poolats till en hög och en låg nivå. Till totalprecisionen användes hög och låg kontroll. Datan från patientjämförelsen bearbetades i Excel och presenterades i linjära regressioner och Bland altman-plot. Som sensitivitetsanalys upprepades den statistiska bearbetningen med de sju högsta värdena exkluderade. Resultat och slutsats Patientjämförelsen mellan Cobas e411 och ADVIA Centaur XPT 1070 samt mellan ADVIA Centaur XPT 1070 och 1071 visade en bra korrelation. ADVIA Centaur XPT mäter dock lägre än Cobas e411, vilket ses i Bland altman-plotten som en metodbias på 30%. Detta ses även efter sensitivitetsanalys med högre värden exkluderade och datan bearbetats på nytt. Precisionsmätningarna visade bra precision med låga CV% för både ADVIA Centaur XPT 1070 och 1071.Med hänsyn till resultatet betraktas bytet till ADVIA Centaur XPT som en risk, varför beslutet fattas att fortsättningsvis analysera PCT på Cobas e411. / Background and purpose The PCT-value is used for observing the development of illness in patients with bacterial infection. During the Covid 19-pandemic, studies have shown that an increased PCT predicts a severe Covid-19.At the University hospital of Örebro, USÖ, the PCT assay is analyzed on the Cobas e411 instrument. The hospitals of Lindesberg and Karlskoga cannot perform the analysis due to a lack of this instrumentation.Since Centaur instruments are available at all three hospitals, performing the analysis on these instruments instead of the Cobas would enable all three hospital laboratories in the county to offer PCT analysis. Method Venous blood with different PCT values where collected from 21 patients and analysed with Siemens ADVIA Centaur XPT and Roche Cobas e411. Within-run precision was tested using pooled samples of low and high PCT concentrations. Between-run precision was tested using controls of low and high PCT concentrations. The data was examined by linear regression and Bland altman-plots using Excel. As a sensitivity analysis, the seven highest values were excluded, and the statistical analysis was repeated. Results and conclusion Despite the values correlating well in the linear regression and the assay had a high precision with a low CV% for both ADVIA Centaur XPT 1070 and 1071, the ADVIA Centaur XPT-instrument systematically measures 30% lower compared to Cobas e411. This method bias could lead to a misclassification of Covid 19-patients. With respect to our results, we consider analysis on ADVIA Centaur XPT to be risky and thus choose to continue analysing on Cobas e411.
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DEVELOPMENT OF HPLC METHODS FOR PHARMACEUTICALLY RELEVANT MOLECULES; METHOD TRANSFER TO UPLC: COMPARING METHODS STATISTICALLY FOR EQUIVALENCEGanti, Satyakala January 2011 (has links)
High Pressure Liquid Chromatography (HPLC) is a well-known and widely used analytical technique which is prevalent throughout the pharmaceutical industry as a research tool. Despite its prominence HPLC possesses some disadvantages, most notably slow analysis time and large consumption of organic solvents. Ultra Pressure Liquid Chromatography (UPLC) is a relatively new technique which offers the same separation capabilities of HPLC with the added benefits of reduced run time and lower solvent consumption. One of the key developments which facilitate the new UPLC technology is sub 2-µm particles used as column packing material. These particles allow for higher operating pressures and increased flow rates while still providing strong separation. Although UPLC technology has been available since early 2000, few laboratories have embraced the new technology as an alternative to HPLC. Besides the resistance to investing in new capital, another major roadblock is converting existing HPLC methodology to UPLC without disruption. This research provides a framework for converting existing HPLC methods to UPLC. An existing HPLC method for analysis of Galantamine hydrobromide was converted to UPLC and validated according to ICH guidelines. A series of statistical evaluations on the validation data were performed to prove the equivalency between the original HPLC and the new UPLC method. This research presents this novel statistical strategy which can be applied to any two methodologies to determine parity. / Chemistry
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A comparative theoretical and empirical analysis of three methods for workplace studiesSellberg, Charlott January 2011 (has links)
Workplace studies in Human-Computer Interaction (HCI) is a research field that has expanded in an explosive way during the recent years. Today there is a wide range of theoretical approaches and methods to choose from, which makes it problematic to make methodological choices both in research and system design. While there have been several studies that assess the different approaches to workplace studies, there seems to be a lack of studies that explore the theoretical and methodological differences between more structured methods within the research field. In this thesis, a comparative theoretical and empirical analysis of three methods for workplace studies is being conducted to deal with the following research problem: What level of theoretical depth and methodological structure is appropriate when conducting methods for workplace studies to inform design of complex socio-technical systems? When using the two criterions descriptive power and application power, to assess Contextual Design (CD), Determining Information Flow Breakdown (DIB), and Capturing Semi-Automated Decision-Making (CASADEMA), important lessons are learned about which methods are acceptable and useful when the purpose is to inform system design.
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Metodjämförelse mellan Immulite® 2000 XPi och Phadia® 250 för analys av IgE-antikroppar i serum : En studie med avseende på IgE-medierad allergi / Method Comparison between Immulite® 2000 XPi and Phadia® 250 for Serum IgE Antibody Analysis : A study with regard to IgE-mediated allergyNilsson, Tilde January 2017 (has links)
Allergi förekommer hos cirka 20 % av befolkningen i Sverige. Av de 20 % bedöms 40 % vara allergiska mot pollen. Allergi uppstår då en individ upprepade gånger exponeras för ett allergiframkallande ämne sk allergen. IgE-antikroppar bildas och binder till basofila granulocyter och mastceller. Den allergiska reaktionen eller överkänslighetsreaktionen av typ I uppkommer när ett allergen exempelvis pollen, kommer i direkt kontakt med IgE-antikroppar på mastceller eller basofila granulocyter. Allergiska individer har högre koncentration av IgE-antikroppar i blodet än icke allergiska. Normal koncentration av IgE i serum hos icke allergiker är <0.35 kU/L. Syftet med studien var att genom analys av serumprover från 50 patienter jämföra två immunokemiska metoder på analysinstrumenten, Siemens immulite® 2000 XPi och Thermo Fisher Phadia® 250, för detektion av IgE-antikroppar riktade mot en inhalationspanel respektive björkpollen. Immulite® 2000 XPi användes som referensmetod. Jämförelsen gjordes för att bedöma om metoderna gav överensstämmande resultat och om Phadia® 250 skulle kunna användas som ett alternativ till rutinmetoden. Studiematerialet bestod av 50 patienter i åldrarna 18–80 år, 17 män (34 %) och 33 kvinnor (66 %). Resultatet visade att metoderna överlag gav överrensstämmande resultat med avseende på positiva och negativa IgE-värden, men att de uppmätta värdena för metoderna saknade överrensstämmelse. Analysresultaten från de båda metoderna gav överlag god korrelation vid analys av specifikt IgE mot björk (R=0,977) men en svagare korrelation vid analys av inhalationspanel (R=0,609). Med hjälp av Man-Whitney u-test sågs en signifikant skillnad vid IgE-analys mot björk (p= 0,0006) däremot sågs inte en signifikant skillnad mellan metodernas IgE-värden mot inhalationspanelerna (p=0,2398). För att kunna utvärdera om Phadia® 250 skulle kunna användas som ett alternativ till rutinmetoden, krävs en större population av prover samt fler analystillfällen. / Allergy is nowadays a public health problem that’s affecting 20 % of the Swedish population. A very common allergen that is related to 40% of all the allergic cases is pollen. Allergic reactions occur when an individual is repeatedly exposed to an allergenic substance called allergene. IgE antibodies then form and bind to basophilic granulocytes and mast cells. The allergic reaction or type I hypersensitivity reaction, occurs when an allergen such as pollen comes into direct contact with IgE antibodies on mast cells or basophilic granulocytes. IgE is produced by plasma cells under the influence of CD4+ T lymphocytes. The IgE antibodies synthesized then sensitize the mast cells and basophilic granulocytes which are the most active cell types involved in allergic reactions. Allergic individuals have a higher concentration of IgE antibodies in the blood than non-allergic. Normal serum IgE concentration in non-allergic patients is <0.35 kU / L. The aim of the study was to compare two immunochemical instruments, Siemens Immulite® 2000 XPi and Thermo Fisher Phadia® 250, by analyzing 50 serum samples to detect possible presence of IgE antibodies directed against an inhalation panel and a single allergen (IgE against birch). The study material consisted of 50 patients between the ages of 18-80, 17 men (34%) and 33 women (66%). The results showed that overall the two methods yielded consistent results due to positive and negative IgE values, but the measured values of the methods lacked concordance. The analysis results from the two methods generally yielded good correlation in the analysis of specific IgE against birch (R = 0.977) but a weaker correlation in the inhalation panel analysis (R = 0.609). Man-Whitney u-test showed a significant difference in IgE analysis against birch (p = 0.0006). However, a significant difference between the IgE values of the methods against the inhalation panels (p = 0.22398) was not observed. To be able to evaluate whether Phadia® 250 could be used as an alternative to the routine method, a larger population of samples and more analytical occasions is required.
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La consommation énergétique du secteur tertiaire marchand : le cas de la France avec données d’enquête à plan de sondage complexe / Energy consumption in tertiary buildings : the French case with complex sample survey dataMadelenat, Jill 16 December 2016 (has links)
Cette thèse porte sur la consommation énergétique du secteur tertiaire marchand en France. Notre approche est empirique, et s’appuie sur l’Enquête sur les Consommations d’Énergie dans le Tertiaire (ECET). À partir d’une revue de littérature consacrée à l’étude économétrique des déterminants de la consommation énergétique des bâtiments (résidentiels ou tertiaires), nous mettons en évidence la coexistence de deux méthodes d’estimation, sur lesquelles nous revenons. Nous exposons également les consensus ou les débats portant sur les effets des déterminants étudiés. Dans la mesure où les données mobilisées dans cette thèse sont issues d’une enquête à plan de sondage complexe, nous présentons les outils statistiques adaptés à l’exploitation de données issues de ce type d’échantillonnage, puis nous analysons la controverse qui continue d’exister sur l’estimation de modèles économétriques sur données d’enquête. Nous mobilisons alors notre base de données pour fournir une première description statistique des consommations énergétiques du secteur tertiaire marchand en France. Cette description statistique s’appuie sur nomenclature que nous construisons afin d’obtenir des informations à l’échelle infra-sectorielle. Enfin, nous utilisons l’ensemble des méthodes et approches préalablement identifiées pour étudier les déterminants de la demande énergétique des établissements tertiaires sur la base d’une analyse économétrique des données de l’ECET. Cela nous conduit à effectuer une double lecture de nos résultats, à la fois comme éléments de réponse à la question de l’impact des variables étudiées sur la demande d’énergie des établissements, et comme éléments de comparaison des différentes méthodes. / This thesis deals with energy consumption in the French tertiary buildings. We adopt an empirical approach based on a French national survey, the Tertiary Buildings Energy Consumption Survey (l’Enquête sur les Consommations d’Énergie dans le Tertiaire (ECET)). From a literature review, we present the econometric analyses of the drivers of energy consumption in buildings (residential and tertiary). This review highlights the coexistence of two estimation methods. We discuss these methods, and then we detail consensus and debates on the effects of every driver that has already been analyzed in the literature. Because the data we use are complex sample survey data, we describe the statistical tools that must be used to analyze this type of data, and next present the still controversial issue of econometric modeling based on survey data. Then we use our database to produce a first statistical description of energy consumption in tertiary buildings. This description is based on a nomenclature that we establish to obtain information at the subsector level. Finally, we use all the methods and approaches identified previously to study the drivers of the tertiary buildings’ energy demand by implementing an econometric analysis on the ECET data. This lead to a double analysis of our results, both as elements of knowledge on the impact of each driver on energy consumption and as materials that help to compare the different methods to use.
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Porovnání cen ovocných dřevin zjištěných zjednodušeným a výnosovým způsobem / Comparison of Fruit Trees Prices Ascertained by the Simplified and Yield MethodJašová, Alena January 2012 (has links)
The Thesis „Comparison of fruit trees prices ascertained by the simplified and yield method“ deals with the comparison of both pricing methods, where there are defined factors on the basis of ascertained facts which have essential influence on price difference of fruit trees and subsequently the proposal to their modification is made.
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Porovnání metod pro odhad omezených veličin s aplikací na ekonomická data / Porovnání metod pro odhad omezených veličin s aplikací na ekonomická dataMusil, Karel January 2013 (has links)
The thesis introduces an overview of techniques for filtering of unobserved variables using a state-space representation of a model and state inequality constraints. It is mainly aimed at a derivation of the linear Kalman filter, its extension into a form of a non-linear filter and imposing state constraints. The state uniform model with noise bounds and the sequential importance sampling, as a method of particle filters using Monte Carlo simulations, are described as alternative methods. These three methods are applied on a simple semi-structural model for a monetary policy analysis. The filtration is based on Czech macroeconomic data and reflects an imposed non-negative state constraint on the interest rate. Results of the algorithms are compared and discussed.
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