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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.
1

Mixed-phase clouds, thin cirrus clouds, and OLR over the tropics: observations, retrievals, and radiative impacts

Lee, Joonsuk 02 June 2009 (has links)
The tropics is a very important region in terms of earth’s radiation budget because the net radiative heating is largest in the tropics and that surplus energy is redistributed by the circulations of oceans and atmospheres. Moreover, a large number of clouds are formed by deep convection and convergence of water vapor. Thus, it is very important to understand the radiative energy balance of the tropics and the effect of clouds on the radiation field. For mixed-phase clouds, error analyses pertaining to the inference of effective particle sizes and optical thicknesses are performed. Errors are calculated with respect to the assumption of a cloud containing solely liquid or ice phase particles. The analyses suggest that the effective particle size inferred for a mixed-phase cloud can be underestimated (or overestimated) if a pure liquid phase (or pure ice phase) is assumed for the cloud, whereas the corresponding cloud optical thickness can be overestimated (or underestimated). The analyses of optical depth and fraction of occurrence for thin cirrus clouds showed that about 40% of pixels flagged as clear-sky contain detectible thin cirrus clouds. The regions of high occurrence and large optical depth located around deep convection showed seasonal variations. The thin cirrus clouds occur more frequently with larger optical depth in the northern (southern) hemisphere during spring and summer (autumn and winter). The net cloud radiative forcing by thin cirrus clouds is positive at the top of atmosphere and is negative at the bottom of atmosphere. The difference in OLR between measurement and model is 4.2 Wm-2 for September 2005. The difference is smaller in moist regions and larger in drier regions. OLR increases with increasing surface temperatures up to 300 K but decreases at surface temperatures larger than 300 K due to the strong absorption of increased water vapor. In summary, if the surface temperature is lower than the threshold of convection (300 K), temperature is a dominant factor in OLR and if the surface temperature is larger than 300 K, OLR is strongly influenced by water vapor.
2

Effect of Temperature on Biogas Production in Anaerobic Treatment of Domestic Wastewater UASB System in Hammarby Sjöstadsverk.

Zhao, Chengyuan January 2011 (has links)
The upflow anaerobic sludge blanket (UASB) reactor is widely used around the world to treat variety of domestic andindustrial wastewater with three main advantages: production of biogas as renewable energy, no need of support structure for development of microorganisms and high rate treatment efficiency with low rate of biomass production. This study evaluates the effect of temperature on biogas production and CODtotal removal in Line 4-UASB system treating domestic wastewater in Hammarby Sjöstadsverk. Eight parameters were examined including the following: Influent and effluent temperature, pH, influent CODtotal, influent rate, effluent CODtotal, volatile fatty acids, biogas production rate and methane concentration. There are eight set temperature and each is stabilized for seven days. The biogas production analysis is focus on UASB 1. Temperature rising from 19°C to 35°C achieves a general benefit result in methane yield rate and CODtotal removal efficiency. The best methane yield rate and CODtotal removal rate are 0.167l/gCODtotal and 56.84% respectively at highest working temperature 33.4°C with OLR 3.072gCODtotal/(l*day) and HRT 4.2h. / Den ökande energiförbrukningen i världen och utsläpp av växthusgaser (GHG) gör det nödvändigt att söka nya hållbara energikällor för att matcha efterfrågan på energi i framtiden. Rötningsteknik med organiskt avfall som förnybar energikälla, ger biogas som i genomsnitt består av 78% CH4, 22% av CO2och spår av H2S (<0.5%), är en idealisk kostnadseffektiv metod. Den Uppåt flödande anaeroba slambäddsreaktorn(UASB) med största fördelarna: biogasproduktion som förnybar energi, hög belastning och hög behandlingseffektivitet med låg produktion av biomassa, inget behov av stödstruktur för utveckling av mikroorganismer, är den viktigaste typen för anaerobt reningssystem. Det finns flera faktorer som påverkar UASB-reaktorns prestanda, såsom temperatur, pH, HRT, Uppåtriktat flödeshastighet, OLR, SRT och VFA. I denna studie är huvudsyftet att med fokus på utvärdering av temperaturpåverkan på biogasproduktion och CODtotal avlägsnat i UASB-systemet Linje 4 som behandlar hushållsspillvatten i Hammarby Sjöstadsverk. Analysen avbiogasproduktionen fokuserades på UASB reaktor 1. Åtta parametrar övervakades för att kontrollera skick inklusive inflöde och utflöde, temperatur, pH, CODtotal inflöde, strömningshastighet för inflöde, CODtotal utflöde, flyktiga fettsyror VFA, biogasproduktionstakt och metankoncentration. Försöken utfördes vid åtta inställda temperaturnivåer och varje nivå stabiliserades i sju dagar. pH och VFA-värde var stabilt under hela försöket. Resultatetvisar att temperaturen har en större inverkan på metanavkastningen och CODtotal avlägsnat än belastningen, OLR. Då temperaturen höjs från 19°C till 35°C erhålls en större metanavkastning och större CODtotal avlägsnat. Den största metanavkastningen och CODtotal avlägsnat är 0,167l/g CODtotal respektive 56.84% vid den högsta arbetstemperaturen 33.4°C med OLR 3.072g CODtotal/(l * dag) och HRT 4.2h. Energibalansen vid olika arbetstemperaturer visaratt det finns en stor skillnad i energibehov för uppvärmning och utbyte avenergi i form av biogas. För att minska klimatpåverkan och nå balans mellan input och output av energi måste energibehovet för uppvärmning reduceras. Energiåtervinning från utflöde till inflöde liksom drift av UASB vid låg temperatur är ämnen som kan studeras vid fortsatt arbete.
3

Etude des relations Onde - Convection - Pluie et influence de la variabilité du flux de mousson en Afrique de l'Ouest

Lavaysse, Christophe 12 April 2006 (has links) (PDF)
Les variations climatiques en Afrique de l'Ouest ont un impact parfois catastrophique, particuliérement au Sahel ou les populations sont exposées aux aléas des ressources en eau. Cette thèse s'inscrit dans la recherche des différents modes de variabilités atmosphèrique et de leurs conséquences sur les processus qui générent les pluies, afin de mieux apprehender le climat et ses variabilités dans cette région. <br />Ce travail porte sur la part de la variabilité des précipitations au Sahel qui peut être expliquée par la variabilité atmosphérique. L'objectif principal est de comprendre comment les perturbations du champ de vent à 700 hPa - les ondes d'est africaines (AEWs) - agissent sur la convectionqui est elle meme à l'origine des précipitations. <br />Après avoir exposé les connaissances actuelles de la climatologie en Afrique de l'Ouest, et expliqué la méthodologie développée pour étudier les ondes d'est, la variabilité des précipitations est étudiée à différentes échelles. La modulation de la convection et des précipitations par les ondes est ensuite traitée et permet de distinguer des secteurs propices aux fortes précipitations, ou au contraire inhibiteurs. L'impact des ondes sur la dynamique et la thermodynamique atmosphérique est également abordé, en particulier dans les basses couches atmosphériques. Un autre aspect original de cette thèse est d'étudier comment les ondes d'est s'insèrent dans la variabilité interannuelle et intra saisonnière du flux de mousson. Après avoir mis en évidence des phases actives et inactives du flux de mousson, le comportement des ondes, de la convection et des précipitations est discriminé en fonction des phases de l'onde.
4

Examining The Association Between Transformational Leadership and Public Organizational Performance

Banee, Rabita Reshmeen 26 August 2022 (has links)
This dissertation examines the association between transformational leadership and public organizational performance using different data and methods. Each of the three articles collected in this dissertation contributes to the scholarship exploring the interplay of transformational leadership and organizational performance using distinct data and interpretive methods, examining the interplay of its elements and a widely used outcome measure – organizational performance as a dependent variable. The first article presents evidence of the empirical studies analyzing the association between transformational leadership and public organizational performance. Based on a formal, replicable search method informed by current practices for the systematic evaluation of published evidence, this review collects and analyzes empirical research articles examining the association between transformational leadership and public organizational performance. A total of seven journal articles were identified that met the study criteria. The measures of the transformational leadership construct in these studies are different but show a common pattern of survey questionnaires with multiple-level responses. Moreover, transformational leadership is found to be positively associated with public organizational performance. Organizational performance is operationalized using several factors such as development, growth, creativity, and effectiveness in the included studies. Acknowledging the gap in the included studies, this review offers two research questions for further exploration to address the gaps in the existing studies. The second article explores the association between the elements of transformational leadership and federal organizational performance in very large and large federal agencies using Ordinal Logistic Regression (OLR) on quantitative survey data drawn from results of the OPM Federal Employment Viewpoint Survey. Statistical findings of this study show a positive relationship between the elements of transformational leadership and organizational performance. This study contributes to the transformational leadership and public management literature by adding the scholarship exploring the association between the elements of transformational leadership and public organizational performance. The third article explores the association between transformational leadership and organizational performance from the experiences and perspectives of U.S. federal agency employees. The data was collected through semi-structured interviews with federal leaders from very large and large agencies, as per the Office of Personnel Management's classification. The perceptions of federal employees reflect the interplay between transformational leadership behaviors and perceptions of organizational performance. The informants' interviews enhance the understanding of transformational leadership-organizational performance association from the employee perspective. A process of thematic coding and interpretation is employed to analyze the interview data. The study findings contribute to the management and leadership literature by exploring the lived experiences of federal employees and their perceptions of the influence of transformational leadership on organizational performance. Moreover, the replicable qualitative interview process and analysis methodology create a pathway for future qualitative research. / Doctor of Philosophy / The influence of leadership is widely studied in terms of organizational performance. Among the leadership theories thought to influence organizational performance, transformational leadership is the most widely studied theory. The theory has gained much attention in the past 40 years for its contribution to many positive organizational outcomes, including meaningful work, organizational commitment, job satisfaction, and organizational performance. Despite a rich history of research in positive organizational outcomes, scholars still argue that there are scopes further to advance the empirical research on transformational leadership theory. Hence, the purpose of this dissertation is to address this claim and analyze the interplay between transformational leadership and public organizational performance. Study findings will contribute to the literature on transformational leadership by empirically examining the interplay of its elements and federal organizational performance. Moreover, the application of three distinct methods and interpretative data analysis will add new evidence to the research of public management and leadership.
5

Avaliação da operação de biodigestor no processo de digestão anaeróbia de resíduos sólidos orgânicos

Schmeier, Nara Paula 20 November 2017 (has links)
Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2018-01-31T12:54:08Z No. of bitstreams: 1 Nara Paula Schmeier_.pdf: 877010 bytes, checksum: f002cde3446d9c5552d9a747ff097801 (MD5) / Made available in DSpace on 2018-01-31T12:54:08Z (GMT). No. of bitstreams: 1 Nara Paula Schmeier_.pdf: 877010 bytes, checksum: f002cde3446d9c5552d9a747ff097801 (MD5) Previous issue date: 2017-11-20 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Petrobras - Petróleo Brasileiro S. A. / PROSUP - Programa de Suporte à Pós-Gradução de Instituições de Ensino Particulares / O processo de digestão anaeróbia tem sido empregado com destaque no tratamento de resíduos sólidos orgânicos, por tratar-se de uma alternativa para amenizar problemas ambientais e também por uma questão energética, visto que possibilita a produção de energia para auxiliar a suprir a alta demanda, em consequência do elevado crescimento populacional e industrial. No entanto, questões relativas a escalas de trabalho, formas de operação, carga orgânica e influência de parâmetros como AGV, alcalinidade e nitrogênio amoniacal (NA) perduram. Desta forma o presente trabalho objetivou avaliar a operação de biodigestor, ao longo de 340 dias, mediante variação de frequências de adição de RSO e cargas orgânicas volumétricas (COV) de 7,98, 7,80, 9,64, 3,28, 4,10 e 5,00 kg STV/m3.d., com média de ST: 339,6 mg/g e umidade: 64%, frente a produção de biogás e CH4. Ademais, também buscou avaliar a influência de parâmetros como AGV, alcalinidade e nitrogênio amoniacal sobre o processo de DA. O sistema experimental foi composto por um biodigestor de câmara única, com volume de 0,28 m³, alimentado com RSO do restaurante universitário e inoculo ambientado a digestão de RSO. O monitoramento do processo experimental foi realizado por meio de caracterização físico-química (pH, DQO, DBO, alcalinidade, AGV, ST, STF, STV, NT, NA, PT e COT) das frações sólidas e líquidas, além da quantificação do biogás (volume e percentual de CH4). O processo de digestão revelou que aplicações de COVs de 3,28, 4,10 e 5,00 kg STV/m3.d. possibilitaram maiores rendimentos de biogás e CH4, em relação a COVs de 7,98, 7,80 e 9,64 kg STV/m3.d. A aplicação continua da COV de 4,10 kg STV/m3.d. apresentou o maior rendimento de biogás e CH4 em função dos STV aplicados, sendo 94,63 NL/kg STV e 45,42 NL/kg STV, respectivamente. No decorrer do processo de digestão, elevadas razões de AGV/Alcalinidade, baixas razões de C/NT e elevadas concentrações de AGV e NA levaram a uma condição de digestão que representou rendimentos reduzidos de biogás e metano. / The anaerobic digestion (AD) process has been used in the treatment of organic solid waste, for being an alternative to ease environmental problems and also an energy issue, since it allows the production of energy to help supplying the high demand, as a result of high population and industrial growth. However, issues concerning work scales, operation forms, organic loads and influence of parameters such as VFA, alkalinity and ammonia nitrogen (AN) to linger. In this way, the objective of this work was to evaluate the biodigester operation, during 340 days, by varying the frequencies of organic solid waste (OSW) and organic loading rate (OLR), of 7,98, 7,80, 9,64, 3,28, 4,10 e 5,00 kg STV/m3.d., with mean de TS: 339,6 mg/g and humidity: 64%, against production of biogas and CH4. In addition, it also sought to evaluate the influence of parameters such as VFA, alkalinity and AN on the DA process. The experimental system consisted of a single chamber biodigester with a volume of 0.28 m³, fed with OSW from a university restaurant and inoculum set to the digestion of OSW. The monitoring of the experimental process was carried out through physicochemical characterization (pH, COD, BOD, alkalinity, VFA, TS, TFS, TVS, TN, AN, PT and TOC) solid and liquid fractions, in addition to the quantification of biogas (volume and percentage of CH4). The digestion process revealed that OLRs applications of 3,28, 4,10 e 5,00 kg TVS/m3.d. allowed higher yields of biogas and CH4, in relation to OLRs of 7,98, 7,80 e 9,64 kg TVS/m3.d. The continuous application of OLR of 4,10 kg TVS/m3.d. showed the highest biogas yield and CH4 as a function of the VTS applied, being 94,63 NL/kg TVS and 45,42 NL/kg TVS, respectively. During the digestion process, high AGV/Alkalinity ratios, low C/N ratios and high concentrations of VFA and AN led to an digestion condition which represented reduced yields of biogas and methane.
6

Two-phase Anaerobic Digestion Of Semi-solid Organic Wastes

Dogan, Eylem 01 February 2008 (has links) (PDF)
The objective of this study is to illustrate that phase separation improves the efficiency of an anaerobic system which digests semi-solid organic wastes. Organic fraction of municipal solid waste (OFMSW) was the semi-solid organic waste investigated. In the first part of the study, the optimum operational conditions for acidified reactor were determined by considering the volatile solid (VS) reductions and average acidification percentages at the end of two experimental sets conducted. Organic loading rate (OLR) of 15 g VS/L.day, pH value of 5.5 and hydraulic retention time (HRT) of 2 days were determined to be the optimum operational conditions for the acidification step. Maximum total volatile fatty acid and average acidification percentage were determined as 12405 mg as HAc/L and 28%, respectively in the reactor operated at optimum conditions. In the second part, an acidification reactor was operated at the optimum conditions determined in the first part. The effluents taken from this reactor as well as the waste stock used to feed this reactor were used as substrate in the biochemical methane potential (BMP) test. The results of BMP test revealed that the reactors fed by acidified samples indicated higher total chemical oxygen demand (tCOD) removals (39%), VS reductions (67%) and cumulative gas productions (265 mL). The result of this study indicated that the separation of the reactors could lead efficiency enhancement in the systems providing that effective control was achieved on acidified reactors.
7

Lasso Regularization for DIF Detection in Graded Response Models

Avila Alejo, Denisse 05 1900 (has links)
Previous research has tested the lasso method for DIF detection in dichotomous items, but limited research is available on this technique for polytomous items. This simulation study compares the lasso method to hybrid ordinal logistic regression to test performance in terms of TP and FP rates when considering sample size, test length, number of response categories, group balance, DIF proportion, and DIF magnitude. Results showed better Type I error control with the lasso, with smaller sample sizes, unbalanced groups, and weak DIF. The lasso also exhibited more stable Type I error control when DIF was weak, and groups were unbalanced. Lastly, low DIF proportion contributed to better Type I error control and higher TP rates with both methods.
8

Analysis of open and laparoscopic liver resections in a german high-volume liver tumor center

Guice, Hanna 04 August 2022 (has links)
In recent years laparoscopic liver surgery established itself into today’s standard of care regarding surgical liver treatment. It was a long way for minimally invasive liver resection to develop and popularize as it was accompanied by initial reservations and concerns. Some of these already had been clarified while other questions still remain and require further investigation in the complex field of laparoscopic liver surgery. Initial concerns with respect to oncological inferiority and technical inapplicability in contrast to open surgery treatment could have been disproved within the framework of retrospective studies. In contribution to that, the aim of the study was to compare the surgical results and postoperative outcomes of consecutive laparoscopic liver resections (LLR) and open liver resections (OLR) at the high-volume liver tumor center of Leipzig university hospital. Since common classification systems for open liver surgery cannot be applied for LLR, the introduction of specific difficulty scoring systems for LLR helps to assess and classify the complexity of minimal invasive liver resection. With an increase in experience, modification of hybrid surgery and the application of novel visualization techniques such as indocyanine green (ICG) staining or hyperspectral imaging (HSI), more challenging procedures were accomplished, that initially would have been contraindicated for the laparoscopic approach (e.g. perihilar cholangiocarcinoma (pCCA) requiring biliary reconstruction). During the years 2018 and 2019 42% of all liver resections were approached laparoscopically at the Leipzig University hospital. A retrospective data analysis of n=231 patients undergoing LLR or OLR for the years 2018 and 2019 was performed and previously determined variables were collected. As a primary outcome measure, the short-term surgical and postoperative outcome of patients receiving LLR (=LLR group) compared to the patient cohort being treated by open resection (=OLR group) was evaluated. All liver resections were executed or assisted by the same two surgeons. Prior to surgery, every case was reviewed in a multidisciplinary tumor-board meeting and primarily assessed for possible minimal invasive approach. Analysis for patient demographics, pathologic diagnosis, radiologic findings and peri- and intraoperative surgical data was carried out. For LLRs intraoperatively, ICG counter perfusion staining was used in anatomic liver resection and direct ICG tumor staining was employed for tumor demarcation. With respect to classification, the extent of OLR was graded according to the Brisbane 2000 terminology in minor and major resections, whereas LLRs were categorized by means of difficulty (in accordance with Ban et al. and Di Fabio et al.). For measurement of surgical complication and assessment of morbidity, the Clavien-Dindo classification was applied. OLR was performed in n=124 (57%) and LLR in n=93 (43%). From all minimally invasive treated patients, 79% were operated totally laparoscopic and 16% were laparoscopic-hand-assisted due to infeasible lesions in the posterosuperior segments 7, 8 and 4a. In 5 cases a conversion to open surgery was necessary because of inaccessibility, tumor infiltration or morbid obesity. 28% of patients had previous upper abdominal surgery, whereof 36% in the OLR group and 19% in the LLR group. Regarding patient demographics, the mean age was significantly higher in OLR and the sex ratio was in favor of men for both groups. Malignant tumor lesions comprised 77%, while 24% were benign lesions. In both groups this larger number of malignant oncologic operation remained valid. The most common benign indications comprised focal nodular hyperplasia (FNH) and liver adenomas. It was shown that patients with CCA and Colorectal liver metastases (CRLM) were predominantly treated by open surgery, while patients with HCC diagnosis received LLR to a greater extent. Concerning the type of liver resection, non-anatomical resections were the most frequent in the cohort with 47%, thereof 55% LLR and 40% OLR. Followed second most by anatomic right and left hemihepatectomies and third most by left lateral resections, which were predominantly performed in laparoscopic technique. On the other hand, extended resections and trisectionectomies were predominantly operated by OLR. Radical lymphadenectomy was performed to a greater extent during OLR. Results showed that the mean operative time was longer for OLR (341 minutes in median) compared to LLR (273 minutes in median). Also the mean length of hospital stay was shorter for LLR patients, as well as abdominal drains were placed to lesser extent in LLR compared to OLR. In regard to R0-resection, R0-rates were higher in LLR with 98% vs. 86% in OLR. Thereby being highest for CRLM resections, followed by HCC and CCA. Putting all liver resections into classification systems, it was found that of all open procedures, 52% had major and 48% underwent minor resection according to Brisbane 2000. From the LLR group, in accordance with Di Fabio et al. 39% were classified as laparoscopic major hepatectomies, comprising 44% laparoscopic traditional major hepatectomies (LTMH) and 56% laparoscopic posterosuperior major hepatectomies (LPMH), which were technically challenging. The difficulty index stated by Ban et al. was classified as low for 8% of all performed LLRs, intermediate for 45% and of high difficulty in even 47%. Relating to morbidity (=Clavien-Dindo 3b or greater), patients with LLR had significantly lower morbidity compared to OLR. The same applies for in-hospital mortality. Our data show that despite the high number of complex and high-difficulty-classified liver resections that were performed, morbidity and mortality rates were low. As mentioned before, R0 resection rate in the LLR group was better than in the OLR group, however, this was not a case matched study, so a direct comparison is not valid. But still the study could demonstrate that the high number of LLRs being performed at the Leipzig University hospital, did not impair R0-resection rates. With an overall hospital mortality rate of 5.9% in the cohort, good results were achieved. Particularly the low rate of 1% in the LLR group speaks for itself and confirms that the development of a minimal invasive liver resection program should be on the right track. The majority of patients in the LLR and OLR group received an oncologic resection, what also resembles the global attitude that minimally invasive techniques are not reserved for selected tumor entities. Still it should be emphasized, the indication for a liver resection should not be loosened just due to minimal invasive accessibility, especially in benign liver lesions. Nevertheless, in the study the majority of benign lesions was operated by LLR. A few patients diagnosed with CCA received LLR. Thereof predominantly iCCA cases were indicated for a minimal invasive approach without biliary duct reconstruction and satisfying short-term outcomes over OLR could be obtained. However, only one case of pCCA which required Roux-Y bile duct reconstruction was treated with LLR in the study group, so if laparoscopic surgery is capable to replace the open approach in terms of treatment strategies for pCCA remains questionable. Patients with CRLM represent the centerpiece of our study population, still only 13% received LLR. The main reason of applying OLR was the high tumor load requiring future liver remnant augmentation strategies. As liver resection is confirmed to be the approach of choice for patients with HCC in cirrhosis, it is not surprising that HCC diagnosis accounted for the major part of LLRS in our collective.:Vorbemerkung und Bibliographie, 3 Abkürzungsverzeichnis, 4 Einführung, 5 - 1. Development of minimal invasive liver surgery, 5 - 2. Prior concerns of LLR, 6 - 3. Benefits of laparoscopic surgery, 6 3.1 General advantages of minimal invasive surgery, 6 3.2 Specific benefits of applying LLR, 7 - 4. Indications for LLR, 7 4.1 Benign liver lesions, 8 4.2 Malignant liver lesions, 8 4.3 Liver transplantation, 9 - 5. Technical supplement, 9 5.1 Hybrid and hand-assisted techniques, 10 - 6. Classification systems, 11 6.1 Difficulty scoring, 11 6.2 Clavien-Dindo Classification ,12 - 7. Limitations of LLR, 12 - 8. Aim of the study, 13 Publikation, 14 Zusammenfassung, 26 Literaturverzeichnis, 30 Darstellung des eignen Beitrags, 34 Selbstständigkeitserklärung, 35
9

Immunhistokemisk undersökning av slemhinnepemfigoid och orala lichenoida reaktioner med epitelsläpp - En pilotstudie

Odobasic, Dennis, Mysliwiec, Marcel January 2020 (has links)
Syfte: Är att ta reda på om man med hjälp av immunhistokemi (IHC) med infärgning avantikroppar mot laminin-5 och C3d kan särskilja mellan slemhinnepemfigoid (MMP) ochorala lichenoida reaktioner (OLR) med epitelsläpp. Vidare undersöks graden inflammation för MMP och OLR för att fastställa om det går att se ett samband mellan grad av inflammation och antikroppsinfärgning.Material och metod: En pilotstudie utfördes på 10 prover med diagnosen MMP respektive 9 prover med OLR, som hämtades från Malmö universitets biobank. Proverna genomgickrutinfärgning respektive antikroppsinfärgning mot laminin-5 och C3d. Granskning av prover skedde i digitalmikroskop. Efteråt delades proverna in i grupper efter var infärgningen sågs. Sammanställning gjordes i Excel med stapeldiagram.Resultat: Ingen tendens till särskiljning ses mellan MMP och OLR avseende infärgning mot laminin-5 och C3d. Positiva utslag för infärgning mot Laminin-5 ses enhetligt på enbart en sida om epitelsläppet hos både snitten för MMP och OLR. Vidare kan det inte ses att snitt med diagnosen OLR har slumpartad infärgning mot laminin-5 på båda sidor om släppet. Det finns en tendens till att MMP-snitt får mer positiva utslag för infärgning mot C3d än för OLR snitt. Graden inflammation var högre i OLR snitt än för MMP snitt.Slutsats: Enligt studien går det inte att, med IHC, med infärgning av antikroppar mot laminin5 och C3d, kunna särskilja MMP och OLR med epitelsläpp. Större urval krävs för definitiva slutsatser. Vidare studier behövs för att utreda om det går att använda IHC för att särskilja MMP och OLR.Nyckelord: C3d, immunhistokemi (IHC), laminin-5, orala lichenoida reaktioner (OLR),slemhinnepemfigoid (MMP) / Aim: To investigate if it is possible to differentiate between the diagnoses mucous membrane pemphigoid (MMP) and oral lichenoid reactions (OLR) with epithelial detachment using immunohistochemistry (IHC) with antibodies against laminin-5 and C3d. Furthermore, the extent of inflammation was examined for MMP and OLR to determine if a correlation between the inflammation and immunostaining is evident.Material and method: A pilot study is conducted using 10 samples diagnosed with MMP and 9 samples diagnosed with OLR, collected from Malmö University’s biobank. H&E staining and immunostaining against laminin-5 and C3d is performed on the samples. Analysis is conducted using a microscope. Samples are then divided into groups depending on the staining. Excel is used to compile the results.Result: No differentiating tendencies are observed between MMP and OLR regardingimmunostaining against laminin-5 and C3d. Immunostaining against laminin-5 is positive for MMP and OLR and is seen continuously on only one side of the epithelial detachment.Furthermore, staining with laminin-5 is not seen as random staining on both sides of theepithelial detachment. Samples with MMP have a higher tendency to stain against C3dcompared to OLR samples. Inflammation is higher in OLR samples than those for MMP.Conclusion: According to this study it is not possible to differentiate between the diagnoses MMP and OLR with epithelial detachment using immunostaining against laminin-5 and C3d. A larger sample size is needed for a definitive conclusion. Additionally, further studies are required to conclude if IHC can be used to differentiate between MMP and OLR.Keywords: C3d, immunohistochemistry (IHC), laminin-5, mucous membrane pemphigoid(MMP), oral lichenoid reactions (OLR)
10

Reator anaeróbio serial (RAS) aplicado no processamento de vinhaça de cana-de-açúcar / Anaerobic serial reactor (ASR) applied in the processing sugarcane stillage

Conceição, Vinicius Masquetti da 09 December 2016 (has links)
O objetivo deste trabalho foi estudar a aplicação de reator anaeróbio serial (RAS) no processamento de vinhaça de cana-de-açúcar para a remoção de matéria orgânica e produção de biogás, submetido ao aumento gradativo de carregamento orgânico. Para tanto, foi utilizado um reator composto por quatro câmaras em série denominadas C1, C2, C3 e C4, com capacidade de 5 L cada, totalizando um volume de 20 L. A primeira etapa do trabalho (Etapa 1) consistiu na operação e monitoramento do reator RAS partindo-se da aplicação da carga orgânica volumétrica (COV) de 0,5 kg DQO m-3.d-1 até a obtenção da COV de 2,5 kg DQO m-3.d-1. Na segunda etapa (Etapa 2) foram operados reatores em batelada sequencial, simulando a operação contínua do reator RAS, visando estudar o efeito do aumento de taxas de carregamento orgânico aplicado. O reator RAS operou sob baixos valores de COVglobal e COALglobal aplicados na Etapa 1, obtendo-se máximas de 2,50 kg DQO m-3.d-1 e 0,167 kg STV m-3.d-1, respectivamente. Os resultados obtidos da Etapa 1 indicam satisfatória remoção global média de matéria orgânica na forma de DQO, superiores a 90 %, propiciada pela adaptação da biomassa ao longo dos reatores sequenciais. O metano apresentou-se como o gás predominante na composição do biogás produzido, com valores acima de 75 %, que confirmam o estabelecimento do sistema metanogênico pleno. Em todos os compartimentos dos reatores sequenciais verificou-se maior abundância relativa para os domínios Archaea e Bacteria os gêneros Methanosaeta, produtores de metano e, T78, responsável pela degradação de açúcares, respectivamente. Principalmente para os reatores C3 e C4, observou-se adaptação de algumas populações para ambos os domínios Bacteria e Archaea indicado pelo menor índice de diversidade e aumento da dominância. O aumento das taxas de carregamento orgânico aplicado ao lodo, estipuladas nos ensaios em batelada na Etapa 2, propiciou o aumento dos valores de carga orgânica aplicada para todos os reatores. Com o aumento do carregamento orgânico aplicado, observa-se o aumento e acúmulo de ácidos orgânicos para todas as fases dos ensaios, principalmente o acético. A produção de metano foi significativa na operação dos reatores em batelada, principalmente em C1. De forma geral, os resultados obtidos demonstraram o bom desempenho do processamento da vinhaça de cana-de açúcar em reator compartimentado tipo RAS para a remoção de matéria orgânica e produção de biogás. / The aim of this study was to investigate the application of an anaerobic serial reactor (ASR) in the sugarcane stillage processing for the removal of organic matter and biogas production, submitted to the gradual increase in organic loading rate. ASR reactor consisted of four reactors operated in series (C1, C2, C3 and C4), each with a reaction volume of 5 L (total volume of 20 L). The first step (Step 1) consisted of reactor operation and monitoring; organic loading rate was gradually increased from 0.5 kg COD m-3d-1 up to 2.5 kg COD m-3 d-1. In the second step (Step 2), sequential batch reactors were operated, simulating the continuous ASR reactor operation, aiming to study the effect of the increase of organic load applied to sludge (OLS). The ASR reactor operated under low values of COVglobal and COALglobal applied in Step 1, obtaining a maximum 2.50 kg COD m-3d-1 and 0.167 kg TVS/m-3d-1, respectively. The results obtained from Step 1 indicated satisfactory removal of the global average organic matter in the form of COD more than 90 %, caused by adaptation of the biomass along the sequential reactors. Methane appeared to be the predominant gas in biogas composition, with values above 75%, which confirmed the establishment of the full methanogenic system. In all compartments of the sequential reactors, there was a higher relative abundance for the domains Archaea and Bacteria of the genera Methanosaeta, methane producers, and T78, which is responsible for degradation of sugars, respectively. Especially for the reactors C3 and C4, the adaptation of some populations for both domains Bacteria and Archaea indicated was observed by the lower diversity index and increase in dominance. The increase of the organic loading rates applied to the sludge, as established in the batch tests, increased the organic load values applied to all reactors. With the increase of organic loading applied, an increase in the accumulation of organic acids, mainly acetic, for all stages and the batch tests. Methane production was significant in the operation of batch reactors, mainly in the C1. In general, the results obtained showed good performance of the processing of the sugarcane stillage in serial reactor (ASR) for the removal of organic matter and biogas production.

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