Diagnosis of acute pancreatitis (AP) is erroneous in up to one third of patients when based on clinical criteria and elevated serum amylase values. Furthermore, according to autopsy reports fatal pancreatitis remains clinically undiagnosed in 22 to 86 % of hospitalised patients. Consequently, search for better methods for the diagnosis of AP seems not only justified but urgent. The pancreas secretes an nonspecific lipase, the carboxylic ester hydrolase (CEH) with molecular properties different from other pancreatic secretory enzymes. These differences may imply that sites and rates of clearances from blood of pancreatic enzymes differ. Except for the pancreas this enzyme is secreted from the lactating mammary gland with milk. A sensitive and reproducible sandwich-ELISA for quantitative determination of CEH was developed. When establishing referent values it was noted that in individuals aged 20 to 65 years serum concentrations of CEH did not depend on age, gender, the time of the day or duration from food intake to blood sampling, or use of nicotine. The mammary gland did not contribute significantly to basal serum levels of CEH; enzyme levels in lactating women or women with mammary tumours were identical to those of the reference population. Seventy percent of patients with the diagnosis AP, based on elevated serum amylase levels and abdominal pain, had elevated CEH values. Among the patients with elevated amylase alone a probable cause of pancreatitis was lacking in the majority of patients. Contrastingly, a likely cause of AP could be identified in all patients presenting with abdominal pain and elevated CEH levels alone. These findings suggested that an elevated CEH level indicated AP more reliably than an elevated amylase level. In patients with AP diagnosed by contrast enhanced computed tomography (CECT) alone, or combined with histopathological diagnosis, serum CEH levels were elevated on admission in all but one patient, and in all within the next 24 h. Furthermore, in patients with severe pancreatitis CEH levels remained at a raised level from the second to at least the 10:th day following admission, whereas a significant decrease was noted in patients with mild pancreatitis. In contrast, serum amylase values were higher in patients with mild pancreatitis during the observation period than in those with severe pancreatitis. CEH levels were higher in patients with three or more Ranson signs than in those with less than three signs from the first day after admission. CEH levels were within referent range in 164 patients without known pancreatic disease admitted due to abdominal emergency conditions, or due to planned surgery for chronic extrapancreatic gastrointestinal diseases, and 16 patients having CECT without pathological findings in the pancreas. This suggests that AP can be excluded with very high degree of probability in presence of non-elevated CEH levels. A sandwich ELISA for determination of Guinea pig CEH and a model for graded pancreatitis in the same species were developed. CEH levels showed proportional to severity of inflammation, thus confirming previous clinical observations. CEH levels in bile were proportional to inflammation, while it was absent in urine. Amylase levels in urine were identical regardless of severity of inflammation, but low in bile. These results suggested differences in sites and rates of clearance between the two enzymes. Seemingly elevated CEH levels allowed identification of clinically significant pancreatitis following ERCP, which amylase levels did not. The presented studies have shown that quantitative determination in serum of CEH by the described method is a more reliable test for the diagnosis of AP than determination of amylase activity. The differences between CEH and amylase are, at least partly, due to differences in molecular properties determining rates and routes of clearances of the two enzymes from serum. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1994, härtill 5 uppsatser.</p> / digitalisering@umu.se

M. Tech. Polymer Technoliogy. / Studies the basic curing, rheological and thermomechanical behaviours of hybrids composed of a VE resin and acrylated epoxidised soyabean oil (AESO). The hybrid systems were cured by free radical initiated radical copolymerisation with styrene. The prospective outcomes were: To find suitable initiators/accelerators for the VE/AESO hybrids which work within the entire composition range? To contribute to the selection of VE resins for AESO modification To establish the optimal quantity of AESO required obtaining the best cure characteristics, the most acceptable reduction in Tg, and stiffness as compared with the parent VE resin.

Είναι γνωστό ότι ο πιο σημαντικός παράγοντας για την προστασία και τη σωστή λειτουργία ενός εξοπλισμού υψηλής τάσης είναι η μόνωση του. Η πιο διαδεδομένη μορφή μόνωσης είναι η χρήση υγρών διηλεκτρικών, και συγκεκριμένα ελαίων. Αρχικά, χρησιμοποιούσαν μόνο ορυκτά έλαια ως μονωτικό υλικό διοτί ήταν εύκολη η διάθεση τους. Τα τελευταία όμως χρόνια, ήθισται να προτιμούνται φυτικά έλαια έναντι των ορυκτών, χάρη των ιδιοτήτων και πλεονεκτημάτων που παρουσιάζουν. Τα βασικά πλεονεκτήματα είναι η φιλικότητα τόσο προς το περιβάλλον όσο και στον άνθρωπο, η μη τοξικότητα τους, το υψηλό σημείο ανάφλεξης, η βιοδιάσπαση τους, καθώς και η βελτίωση της απόδοσης του μετασχηματιστή. Σκοπός της παρούσας διπλωματικής εργασίας είναι η διερεύνηση της συμπεριφοράς του φυτικού ελαίου FR3 κατά τη διάρκεια καταπόνησης του με εναλλασσόμενη τάση (AC) και η σύγκριση του με το ορυκτό έλαιο. Ακόμη, στόχος μας είναι να παρατηρήσουμε τη συμπεριφορά του FR3 σε συνδυασμό με μονωτικό χαρτί, αφού γνωρίζουμε ότι τα τυλίγματα μετασχηματιστών υψηλής τάσης μονώνονται και από τα 2 υλικά. Για το λόγο αυτό χρησιμοποιήθηκε η συσκευη BAUR oil tester DTA 100C που αποτελεί κομμάτι του ηλεκτρολογικού εξοπλισμού του εργαστηρίου των υψηλών τάσεων. Η παραγωγή γραμμικά αυξανόμενης εναλλασσόμενης (AC) τάσης με σταθερό ρυθμό 2kVrms/s και οι μετρήσεις της τάσης διάσπασης έγιναν από τη συσκευή αυτή. Τα διάκενα στα οποία καταπονήθηκε το φυτικό έλαιο είναι: rogowski 2mm, ακίδα-πλάκα 2mm, rogowski-πλάκα 2.5mm.Στη συνέχεια, πραγματοποιήσαμε μετρήσεις με διάταξη rogowski 2.5mm σε φυτικό λάδι χωρίς ανάδευση και σε καταπονημένο σε κρουστική τάση. Οι επόμενες μετρήσεις αφορούσαν το σύνθετο διάκενο χαρτί –λάδι και χρησιμοποιήσαμε 2 τύπους χαρτιού: DPP PAPER και KRAFT PAPER σε διάταξη rogowski 2.5mm. Τέλος, χρησιμοποιήσαμε ορυκτό έλαιο σε διάκενα rogowski 2.5mm και Ακίδα πλάκα 2,5 mm Επίσης, για να είμαστε άρτιοι στη σύγκριση των δύο τύπων ελαίων, πραγματοποιήσαμε αναλυτική στατιστική έρευνα ώστε να διαπιστώσουμε αν η κατανομή των πειραματικών αποτελεσμάτων προσεγγίζει την κανονική. Συγκεκριμένα, χρησιμοποιήσαμε το διάγραμμα διασποράς για την εκτίμηση της κατανομής. Έπειτα, με τη χρήση της συνάρτησης πυκνότητας πιθανότητας παρατηρήσαμε εποπτικά αν τα πειραματικά αποτελέσματα ακολουθούν κανονική κατανομή και υπολογίσαμε την ασσυμμετρία και την κυρτωση αυτών. Tέλος, χρησιμοποιήθηκαν τρία κριτήρια κανονικότητας, το Shapiro-Wilk, το Kolmogrov-Smirnov, και το Anderson-Darling καθώς και το διάγραμμα Normal Plot. Κρίνοντας από τα αποτελέσματα, προκύπτει ότι η τάσης διάπασης για το φυτικό έλαιο είναι μεγαλύτερη σε σχέση με το ορυκτό. Επίσης, είναι φανερό ότι η ύπαρξη σύνθετου διακένου (έλαιο – χαρτί) μειώνει την τάση διάσπασης του FR3. Τέλος, φαίνεται ότι σχεδόν για όλες τις διατάξεις, τα πειραματικά αποτελέσματα ακολουθούν την κανονική κατανομή. / It is known that the most important factor for the protection and proper operation of high voltage equipment is the insulation achievements. The most widespread form of insulation is the use of liquid dielectrics, manely dielectric oils. Initially, only mineral oil were used as an insulating material because it was easily available. However, the last decades vegetable oils are preferred to fossil thanks to the properties and advantages they present. The main advantages are the friendliness of both the environment and humans, non- toxicity, high flash point, biodegradation, as well as improving the efficiency of the transformer. The purpose of this thesis is to investigate the behavior of natural oil FR3 during stress with alternating current (AC) and compared with the mineral oil. Furthermore, our aim is to observe the behavior of this oil in combination with insulating paper, since we know that the high voltage transformer windings are insulated from the two materials. For this reason, using the device BAUR oil tester DTA 100C which is part of the electrical equipment of High Voltage laboratory. The production increased linearly alternating (ac) voltage steadily 2kVrms/s, and measurements of the breakdown voltage were made of this device.The gaps that we were measured are: rogowski 2mm, point-plane 2mm, rogowski-plane 2mm. Then, we measured the breakdown voltage for rogowski 2,5mm without stirring and for an overworked oil. Next measurments concered the combination of paper-oil, where we used two types of insulating paper:DPP and KRAFT PAPER (rogowski 2.5mm).finally we measured mineral oil in gaps: rogowski 2.5 mm and point-plane 2.5 mm Also, being correct to compare the two types of oils, we conducted a detailed survey about whether the experimental results follow the normal distribution. Specifically, we used the scatter plot to estimate the distribution of our experimental results. Then, using the probability density function we observed if the experimental results follow a normal distribution and calculated the coefficients of skewness and kurtosis. Finally, we used two hypothesis tests, the Shapiro – Wilk test,the Kolomogrov-Smirnov test and the Anderson-Darling, as well as the Normal Probability Plot. Αccording to the results, we observe that the breakdown voltage of natural ester oil is greater than mineral’s oil. Also, it is obvious that the existence of a complex gap (oil-paper) reduces the breakdown voltage. Finally, it seems that for almost all the provisions, the experimental results follow the normal distribution.

Cette thèse s'inscrit dans le contexte de la Chaire Industrielle Bioplastiques, financé par MINES ParisTech et cinq entreprises partenaires : Arkema, L'Oréal, Nestlé, PSA Peugeot-Citroën et Schneider Electric, qui vise à développer de nouveaux matériaux biosourcés durables. L'objectif global de la thèse est de trouver de nouvelles propriétés à une ancienne famille de plastiques biosourcés - les esters de cellulose - en les mélangeant avec une polyoléfine. Nous avons débuté l'étude par une étape de screening qui nous a permis de caractériser l'ester de cellulose retenu (acétobutyrate de cellulose ou CAB) et de définir l'objectif de la thèse : améliorer la résistance au choc du CAB en y ajoutant une phase polyoléfinique finement dispersée. Le CAB est, en effet, particulièrement fragile : sa résilience est inférieure à 2 kJ/m² lors d'un choc Charpy entaillé. Pour diminuer la taille de nodules de la phase dispersée et la distance qui les sépare, deux approches ont été utilisés. Premièrement, plusieurs mélanges de CAB et de polyéthylènes (PE) de densités différentes ont été préparés par mélangeur interne. Des compatibilisants maléisés ont été utilisés pour diminuer la tension interfaciale entre les phases. Les tailles des nodules, mesurées par microscopie électronique à balayage se sont classées suivant les rapports de viscosité et d'élasticité (PE/CAB), mesurés par rhéométrie dynamique. La résilience de ces mélanges a été augmentée par rapport au CAB mais n'a pas dépassé 6 kJ/m². Dans la seconde approche, des polyoléfines fonctionnalisées (maléisées) ont été utilisées comme unique phase dispersée. La fonctionnalité accrue a permis d'améliorer l'adhésion interfaciale. La taille des nodules et leur espacement ont été considérablement réduits. Les mélanges sélectionnés ont été préparés par extrusion bi-vis et les éprouvettes de résistance au choc ont été préparées par injection. Pour quelques formulations, une longueur moyenne de ligaments de matrice (séparant deux nodules voisins) particulièrement petite (0,1 µm) a permis d'atteindre la transition fragile-ductile du matériau et une résilience supérieure à 60 kJ/m².

Through a full factorial design experiment, the effects of time between worts, wort aeration and yeast dosage in production of a pale lager beer were examined in the beer process at Spendrups Bryggeri AB. The aim was to learn how different parameters may affect the yeast fermentation performance during beer production. Response variables used were the concentrations of ethyl acetate and isoamyl acetate, free amino nitrogen (FAN) degradation and change in extract. A statistical analysis showed that the concentration of ethyl acetate is dependent on yeast dosage and the interaction between time between worts and aeration while the isoamyl acetate concentration is dependent on yeast dosage and time between worts. No parameters are statistically significant for FAN degradation while the change in extract is dependent on the yeast dosage. Due to botched runs, mostly because of aeration problems, it was not possible to verify theoretical parameter values and responses. Since the aeration was not properly performed, the management of the aeration control should be further investigated. Ester analysis and analysis of FAN were performed as worts entered and exited horizontal fermentation tanks. An additional analysis of ester content was also performed as the early stage beer was transferred into lagering tanks. Cell viability as well as extract, pH and tank temperature was measured daily to verify the state of fermentation. Statistical calculations showed that when using NucleoCounter YC-100, there is no significant difference between analysis made of samples homogenized by a magnetic stirrer and samples shaken by hand.

Ordered mesoporous silicas have been shown to have a variety of useful applications ranging from adsorbents for containments to supports for catalysts. While these materials have received a good deal of attention in the literature there is still much opportunity for new technologies. We present research describing a novel approach to incorporate functionality onto the pore surfaces of these materials as well as a highly active catalyst for the Suzuki-Miyaura reaction. Our approach to selectively graft functionality on to the pore walls of the mesoporous silicas SBA-15 and MCM-41 involves treating the materials loaded with a structure directing agent (SDA), with hexamethyldisilazane that passivates the external surface through silylation. Once the SDA is removed the mesopores can be functionalized selectively using standard methods. A test designed to look at the passivation layer is also described. The catalyst developed is designated Pd-SBA-15-SH(g) and it is active for the Suzuki-Miyaura reaction. The activity, recyclability and leaching of Pd-SBA-15-SH(g) was found to be superior to related materials. A mechanistic analysis suggests the catalyst is a reservoir for soluble Pd metal. A key challenge that is holding back wide scale application of ammonia borane (NH3BH3) as a hydrogen storage material for mobile applications is the dearth of regeneration strategies. Presented are our forays into the development of an organic hydride based regeneration strategy. The first phase of the project focused on the reaction between Hantzsch esters and B(C6F5)3. N-substituted Hantzsch esters were found to transfer hydride to boron in >90 % yield. Mechanistic analysis of the reaction suggests either a SET mechanism or a highly asynchronous transition state. A novel hydride transfer equilibrium promoted by B(C6F5)3 was observed and it operated at temperatures below -10 ºC. N,N-ditertbutyl-dihydroimidazole is also an effective hydride donor to B(C6F5)3 as well as other Lewis acids that are more relevant mimics to those invoked in regeneration schemes. When the redistribution of B(SPh)3 is carried out with N,N-ditertbutyl-dihydroimidazole in the presence of NEt3 and CH2Cl2 at 50 ºC, BH2(NEt)3(SPh) is formed. CH2Cl2 functions as a thiol scavenger under the reaction conditions. 1-Octene trapping experiments provided indirect evidence for the formation of diborane, a critical component in the regeneration of NH3BH3. / Thesis (Ph.D, Chemistry) -- Queen's University, 2011-09-09 14:51:54.697

<p>The production of biodiesel (methyl esters) from vegetable oils represents analternative means of producing liquid fuels from biomass, and one which is growing rapidly in commercial importance and relevance due to increase in petroleum prices and the environmental advantages the process offers. Commercially, biodiesel is produced from vegetable oils, as well as from waste cooking oils and animal fats. These oils are typically composed of C14-C20 fatty acid triglycerides. In order to produce a fuel that is suitable for use in diesel engines, these triglycerides are usually converted into the respective mono alkyl esters by base-catalyzed transesterification with short chain alcohol, usually methanol. In the first part of this study, the transesterification reactions of three different vegetable oils / sunflower (SFO), soybean (SBO) and waste cooking oil (WCO) with methanol was studied using potassium hydroxide as catalyst in a conventional batch process. The production of biodiesel from waste cooking oil was also studied via continuous operation systems (employing the use of low frequency ultrasonic technology and the jet loop reactor). The characterisation of the feedstock used and the methyl ester products were determined by different analytical techniques such as gas chromatography (GC), high performance liquid chromatography (HPLC) and thin layer chromatography (TLC). The effects of different reaction parameters (catalyst amount, methanol to oil ratio, reaction temperature, reaction time) on methyl ester/FAME yield were studied and the optimum reaction conditions of the different process systems were determined. The optimum reaction conditions for production of methyl esters via the batch process with the fresh oil samples (SFO and SBO) were established as follows: a reaction time of 60 min at 60 &ordm / C with a methanol: oil ratio of 6:1 and 1.0 KOH % wt/wt of oil / while the optimum reaction conditions for the used oil (WCO) was observed at a reaction time of 90 min at 60 &ordm / C, methanol: oil ratio of 6:1 and 1.5% KOH wt/wt of oil. The optimum reaction conditions for the transesterification of the WCO via ultrasound technology applied in a continuous system in this study were: a reaction time of 30 min, 30 &ordm / C, 6:1 methanol/oil ratio and a 0.75 wt% (KOH) catalyst concentration. The ultrasound assisted transesterification reactions performed at optimum conditions on the different oil samples led to higher yields of methyl esters (96.8, 98.32 and 97.65 % for WCO, SFO and SBO respectively) compared to methyl esters yields (90, 95 and 96 % for WCO, SFO and SBO respectively) obtained when using conventional batch procedures. A considerable increase in yields of the methyl esters in the ultrasound assisted reaction process were obtained at room temperature, in a remarkably short time span (completed in 30 min) and with a lower amount of catalyst (0.75 wt % KOH) while the results from the continuous jet loop process system showed even better results, at an optimum reaction condition of 25 min of reaction, a methanol: oil ratio of 4:1 and a catalyst amount of 0.5 wt%. This new jet loop process allowed an added advantage of intense agitation for an efficient separation and adequate purification of the methyl esters phase at a reduced time of 30 min. The use of homogeneous catalysts in conventional processes poses many disadvantages / heterogeneous catalysts on the other hand are attractive on the basis that their use could enable the biodiesel production to be more readily performed as a continuous process resulting in low production costs. Consequently, a solid base catalyst (KNO3/FA) prepared from fly ash (obtained from Arnot coal power station, South Africa) and a new zeolite, FA/Na-X synthesized from the same fly ash were used as solid base catalysts in the transesterification reactions in the conversion of a variety of oil feedstock with methanol to methyl esters. Since fly ash is a waste product generated from the combustion of coal for power generation, its utilization in this manner would allow for its beneficiation (as a catalytic support material and raw material for zeolite synthesis) in an environmentally friendly way aimed at making the transesterification process reasonably viable. Arnot fly ash (AFA) was loaded with potassium (using potassium nitrate as precursor) via a wet impregnation method while the synthesized zeolite FA/Na-X was ion exchanged with potassium (using potassium acetate as precursor) to obtain the KNO3/FA and FA/K-X catalysts respectively. Several analytical techniques were applied for characterization purposes. The results of the XRD and XRF showed that the AFA predominantly contained some mineral phases such as quartz, mullite, calcite and lime. The high concentration of CaO in AFA was apparent to be beneficial for the use of fresh fly ash as a support material in the heterogeneous catalysed transesterification reactions. XRD characterisation of KNO3/FA results indicated that the structure of KNO3/FA gradually changed with the increase in KNO3 loading. The catalyst function was retained until the loading of KNO3 was over 10 %. IR spectra showed that the KNO3 was decomposed to K2O on the fly ash support during preparation at a calcination temperature of 500 &ordm / C. The CO2-TPD of the KNO3/FA catalysts showed that two basic catalytic sites were generated which were responsible for high catalytic abilities observed in the transesterification reactions of sunflower oil to methyl esters. On the other hand, XRD results for the as- received zeolite synthesized from AFA showed typical diffraction peaks of zeolite NaX. SEM images of the FA /NaX showed nano platelets unique morphology different from well known pyramidal octahedral shaped crystal formation of faujasite zeolites and the morphology of the FA /KX zeolite did not show any significant difference after ion exchange. The fly ash derived zeolite NaX (FA /NaX) exhibited a high surface area of 320 m2/g. The application of the KNO3/FA catalysts in the conversion reactions to produce methyl esters (biodiesel) via transesterification reactions revealed methyl ester yield of 87.5 % with 10 wt% KNO3 at optimum reaction conditions of methanol: oil ratio of 15:1, 5 h reaction time, catalyst amount of 15 g and reaction temperature 160 &deg / C, while with the use of the zeolite FA/K-X catalyst, a FAME yield of 83.53 % was obtained for 8 h using the ion exchanged Arnot fly ash zeolite NaX catalyst (FA/KX) at reaction conditions of methanol: oil ratio of 6:1, catalyst amount of 3 % wt/wt of oil and reaction temperature of 65 &ordm / C. Several studies have been carried out on the production of biodiesel using different heterogeneous catalysts but this study has been able to uniquely demonstrate the utilization of South African Class F AFA both as a catalyst support and as a raw material for zeolite synthesis / these catalyst materials subsequently applied sucessfully as solid base catalysts in the production of biodiesel.</p>

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

Currently, cancer is the second leading cause of death in the United States. Conventional cancer treatment includes chemotherapy, radiation, and surgical resection, but unfortunately, all of these methods have significant drawbacks. Hyperthermia, the heating of cancerous tissues to between 41 and 45°C, has been shown to improve the efficacy of cancer therapy when used in conjunction with irradiation and/or chemotherapy. In this work, a novel method for remotely administering heat is presented. This method involves heating of tumor tissue using hydrogel nanocomposites containing magnetic nanoparticles which can be remotely heated upon exposure to an external alternating magnetic field (AMF). The iron oxide nanoparticles contained in the hydrogel nanocomposites are able to heat via an AMF due to Brownian and Neel relaxation processes. The administration of hyperthermia via hydrogel nanocomposites allows for local delivery of heat to tumor tissue while also providing a drug depot to deliver chemotherapeutic agents. Both in vivo and in vitro studies have demonstrated that numerous chemotherapeutic agents, when used in conjunction with hyperthermia, show improved efficacy in treating cancer Various magnetic hydrogel nanocomposites were synthesized and characterized for this work including poly(ethylene glycol) (PEG)-based hydrogels, which were studied due to their inherent biocompatibility and “stealth” properties, as well as, poly(β-amino ester) (PBAE)-based hydrogels which have tailorable degradation properties. The PEG hydrogels were investigated for their temperature-responsiveness swelling, mechanical strength, heating capabilities, biocompatibility, ability to kill M059K glioblastoma cells via thermoablation, and the ability to deliver paclitaxel, a chemotherapeutic agent. PBAE hydrogels were also characterized for their degradation and swelling properties, ability to heat upon exposure to an AMF, biocompatibility, mechanical strength, and ability to deliver paclitaxel in a controlled fashion. Additionally, multiple cancer cell lines were exposed to a combination of paclitaxel and heat (at 42.5 °C) in vitro and it was shown that A539 lung carcinoma cells exhibit higher cytotoxicity when exposed to both heat and paclitaxel than either treatment alone. Overall, magnetic hydrogel nanocomposites are promising materials that can be utilized for the multi-modality treatment of cancer through the synergistic delivery of both heat and chemotherapeutic agents.

2012 IEEE International Symposium on Electrical Insulation (ISEI), June 10-13, 2012, Ritz Carlton Hotel, San Juan, PR, USA