11 research outputs found
Nucleophilic Substitution Reactions for Positron Emission Tomography; Factors Influencing the Reactivity of [18F]Fluoride
The papers of this thesis are not available in Munin: 1. Hjelstuen, O. K., Svadberg A., Olberg, D. E. and Rosser, M.: 'Standardization of fluorine-18 manufacturing processes: New scientific challenges for PET', European Journal of Pharmaceutics and Biopharmaceutics (2011), 78, 307-313. Available at http://dx.doi.org/10.1016/j.ejpb.2011.01.002 2. Svadberg, A., Clarke, A., Dyrstad, K., Martinsen, I. and Hjelstuen, O. K.: 'A critical study
on borosilicate glassware and silica-based QMA's in nucleophilic substitution with [18F]fluoride : influence of aluminum, boron and silicon on the reactivity of [18F]fluoride', Applied Radiation and Isotopes (2011), 69, 289-294. Available at http://dx.doi.org/10.1016/j.apradiso.2010.09.013 3. Svadberg, A., Wickstrøm, T. and Hjelstuen, O. K.: 'Degradation of acetonitrile in eluent solutions for [18F]fluoride PET chemistry : impact on radiosynthesis of [18F]FACBC and [18F]FDG', Journal of Labelled Compounds and Radiopharmaceuticals (2012), vol. 55, no. 3:97–102. Available at http://dx.doi.org/10.1002/jlcr.1956 4. Svadberg, A., Dyrstad, K. and Hjelstuen, O. K.: 'Cationic contaminants in irradiated [18O]H2O and their effect on [18F]F- reactivity' (submitted paper to Applied Radiation and Isotopes)Clinical use of positron emission tomography (PET) is expanding from use of [18F]FDG to a wider spectrum of PET-tracers and proprietary PET radiopharmaceuticals. The development of new PET-tracers is however far from trivial and the radiochemistry is a major limiting factor. Nucleophilic substitution reactions with [18F]fluoride generally suffer from inconsistent labeling yields. There is a need to investigate the generic impurities causing such inconsistency in order to build more robust syntheses that also are in line with regulatory demands for approval of new PET radiopharmaceuticals.
The aim of this thesis was to investigate how pharmaceutical-chemical impurities from a typical synthesis setup may influence labeling yields in nucleophilic substitution reactions with [18F]fluoride. Following areas were studied: Borosilicate glassware, Kryptofix based eluent solutions, anion-exchange cartridges, and irradiated [18O]water.
Materials and methods
The new commercial synthesizer, GE FASTlab™, was used as an investigational platform using three different benchmark reactions: [18F]FACBC, [18F]FDG and [18F]Flutemetamol. The importance of identified impurities was investigated with radiochemical yield as the measured response.
Eluent solutions of K222, K2CO3 in aqueous acetonitrile extracted ppm levels of silicon, boron and aluminum if stored in borosilicate glass at room temperature (days). It was revealed that relevant levels of aluminum present in the eluent solution (0.4–2 ppm) could pass a polymer-based anion-exchange cartridge and cause detrimental effects on the RCY.
Calcium, magnesium, zinc and aluminum were identified as potential impurities in irradiated [18O]water. Aluminum, if present in the [18O]water, was fully adsorbed on the anion-exchange cartridge and to a variable degree co-eluted with [18F]fluoride, causing detrimental effect on the RCY. Type of anion-exchange cartridge was a major determining factor for the amount of eluted aluminum.
Eluent solutions containing K222 and K2CO3 in aqueous acetonitrile degraded relatively quickly when stored at room temperature or above. Acetate, one of the degradation products would negatively affect RCY if generated at sufficient levels (hundreds of ppm). A methanol-based eluent solution was successfully developed, showing no degradation after 6 months of storage at 50 oC
Strategies and scenarios for wireless information systems
Thesis (S.M.M.O.T.)--Massachusetts Institute of Technology, Sloan School of Management, Management of Technology Program, 2000.Includes bibliographical references (leaves 73-74).This thesis investigates the emerging market for wireless information services caused by the convergence of Internet, information and telecommunication technologies. Portals and content and application providers are now entering a market previously controlled and dominated by the wireless network providers. This thesis starts with a description of this new value chain and a discussion of the power of each of the participants. This is followed by an overview of the market size and the projections for the future, together with a description of services currently available around the world and associated business models. A case study on wireless financial services follows next, to illustrate what might happen and be available in other industries in the near future. I developed three scenarios for the wireless Internet services the next three years: ** A closed case: The Wireless Network As A Toll Road ** Status quo: Internet and Commerce Without Wires, Why The Hype? ** An open case: New Unique and Value-added Offerings Create New Markets I used interviews with leading industry expert to validate these scenarios. There was a general consensus among the experts and managers that my most optimistic and pessimistic scenarios represent the likely range of possible future outcomes. The majority believes we will move from the current closed (i.e. the pessimistic) case to the open model (i.e. the optimistic scenario) ending up somewhere close to the open case. The experts believed that the open model would eventually "win" due to technical improvements and competitive pressure. Based on this, I arrived at ten strategies for successful market penetration of wireless information services. The top three are; act quickly to gain first-mover advantages, enter into profit sharing because this is a complex and networked marketplace, and thirdly address unspoken and subtle needs. The main challenges facing the players in this market are: ** They have to share the ownership and responsibility of the customer experience ** The need for developing open standards together to fuel the growth of the market ** That the timing of the products and services must be right the first time.by Andres Svadberg Hatloy.S.M.M.O.T
Beyond the hype: A bibliometric analysis deconstructing research on digitalization
The accelerating emergent field of research addressing digitalization and
related topics is complex, unstructured and hyped. Consequently, both
research and practice lack a rigorous foundation of prior published
research to underpin and direct future exploration into the opportunities
and challenges provided by these exciting new digital technologies. This
study employed a bibliometric analysis to explore extant published
research within the digitalization field. We identified key articles that have
enabled us to distinguish between interrelated digitalization concepts.
Subsequently, we propose a taxonomy with characteristics for different
levels of digitalization. The taxonomy contributes with dimensions that
create different commercial and organizational opportunities and
challenges at the different levels. The taxonomy offers a vantage point for
subsequent empirical and conceptual research to extend insight on related
digitalization themes, and especially related to innovation and strategy
decisions on scalability, automation, channel selection and connectivity
Digitalisering av bankbransjen
This PhD thesis aims at exploring the mechanisms through which Albanian immigrants have been incorporated into the local labour market of Heraklion, Crete, and their contribution to local economic development. In the first part of this thesis a critical theoretical review of immigration is carried out. In the second part, the empirical research (fieldwork) sheds light upon certain aspects of the theoretical review. The close relationship between immigration and informal labour is highlighted. In approaching the nature of informal immigrant work in Greece, global socio-economic changes (such as the shift from fordism to flexible accumulation) were related to specific features of Greek economy, such as the weak and inefficient state planning apparatus, the extended small-real estate holdings, the established self-employment practices and the irresponsibility of a large part of the entrepreneurial community. Concurrently, this thesis aims to identify how Greek state’s immigration policies, especially during the early 1990’s, reinforced the inflow of informal immigrant labour for the interest of private firms following labour intensive, low cost, restructuring strategies.This thesis is a theoretically informed empirical research. The empirical study is a qualitative research based on a limited number of in-depth interviews (30) that took place in Albanian immigrant households in the city of Heraklion, Crete. The research findings are indicative of the concrete sample without claiming generalization and applicability in the total immigrant Albanian population of the city. It is hoped that the lack of generalization is counterbalanced by a deeper understanding of the causal mechanisms and processes underlying migration and local labour market in the concrete case. A basic conclusion of the thesis is that the supply of jobs in the informal sector of the local economy played a crucial role in attracting the Albanian immigrants of the sample to the area during the early 1990’s. However, as their economic status started gradually to improve, many of them shifted into better paid and more secure jobs in the formal sector of the local economy. As a result of this, the Albanian immigrants of the study’s sample contributed in many ways to local economic development, either by increasing the levels of consumption, or by creating new jobs in the area.Η παρούσα διδακτορική διατριβή έχει σαν αντικείμενό της τη διερεύνηση του τρόπου ένταξης των Αλβανών μεταναστών/μεταναστευτριών στην τοπική αγορά εργασίας του Ηρακλείου Κρήτης και της συμβολής τους στην τοπική οικονομική ανάπτυξη. Η διατριβή αποτελείται από τη κριτική θεωρητική επισκόπηση του ζητήματος καθώς και από την μελέτη περίπτωσης (case study), η οποία εμπλουτίζει και φωτίζει πτυχές της θεωρητικής επισκόπησης. Στην θεωρητική επισκόπηση εξετάζονται οι σχέσεις της μετανάστευσης με τις άτυπες μορφές απασχόλησης. Η ανάλυση του φαινόμενου της άτυπης εργασίας στη χώρα μας καταδεικνύει ότι είναι ένα φαινόμενο πολύπλοκο στη γιγάντωση του οποίου συντέλεσαν οι παγκόσμιες αλλαγές (πέρασμα από τον φορντισμό στη ευέλικτη συσσώρευση και στην αναγκαιότητα για φθηνό εργατικό δυναμικό), αλλαγές που διαπλέκονται με βασικά χαρακτηριστικά της ελληνικής οικονομίας, όπως ο αδύναμος και αναποτελεσματικός κρατικός προγραμματισμός, η εκτεταμένη μικρο-ιδιοκτησία, η αυτοαπασχόληση, καθώς και η ασυδοσία ενός μεγάλου τμήματος του επιχειρηματικού κόσμου. Όσον αφορά τις κυβερνητικές επιλογές σε θέματα μεταναστευτικής πολιτικής μετά το 1990, αυτές οδήγησαν στην ενίσχυση της άτυπης αγοράς εργασίας και την τροφοδοσία της με φθηνό εργατικό δυναμικό μεταναστών. Μεθοδολογικά, η προκειμένη διατριβή αποτελεί μια θεωρητικά ενημερωμένη εμπειρική έρευνα. Η έρευνα πεδίου είναι ποιοτικού χαρακτήρα και βασίζεται σε περιορισμένο αριθμό συνεντεύξεων που πραγματοποιήθηκαν σε νοικοκυριά Αλβανών μεταναστών στο Ηράκλειο Κρήτης. Συνολικά πραγματοποιήθηκαν 30 συνεντεύξεις σε βάθος με τη βοήθεια ημιδομημένου ερωτηματολογίου. Τα ευρήματα της έρευνας είναι ενδεικτικά του συγκεκριμένου δείγματος χωρίς να διεκδικούν χαρακτηριστικά αντιπροσωπευτικότητας του συνόλου των Αλβανών μεταναστών της πόλης. Η έλλειψη αντιπροσωπευτικότητας, ευελπιστούμε ότι ισοσταθμίζεται από τη σε βάθος διερεύνηση των αιτιακών μηχανισμών, διαδικασιών και σχέσεων μεταξύ μετανάστευσης και τοπικής αγοράς εργασίας στη συγκεκριμένη περίπτωση. Βασικό συμπέρασμα της έρευνας είναι ότι η άτυπη εργασία διαδραμάτισε πολύ σπουδαίο ρόλο στην προσέλκυση των Αλβανών μεταναστών του δείγματος, οι οποίοι εργάζονταν ανασφάλιστα και σε εργασίες που οι Έλληνες αρνούνταν να αναλάβουν. Επίσης, συνάγεται η ανοδική οικονομική κινητικότητα των Αλβανών του δείγματος, καθώς στην πλειοψηφία τους εργάζονται σήμερα πλέον με ικανοποιητικές αμοιβές και με την απαραίτητη ασφάλιση. Όσον αφορά την οικονομική συνεισφορά τους μπορούμε να πούμε ότι ενίσχυσαν την τοπική οικονομία καθώς βοήθησαν με πολλούς τρόπους στην αύξηση της τοπικής κατανάλωσης. Επιπλέον, οι Αλβανοί εργαζόμενοι του δείγματος της έρευνας δεν φαίνεται να αφαίρεσαν θέσεις εργασίας από Έλληνες εργαζόμενους, ή ακόμα και αν αυτό έγινε σε κάποιες περιπτώσεις, με την εργασία τους δημιούργησαν νέες θέσεις απασχόλησης. Επίσης, γνώρισαν σημαντική άνθηση τομείς της οικονομίας όπως ο κατασκευαστικός τομέας που στην Ελλάδα, με δεδομένη την τεχνολογική στασιμότητα της χώρας, μόνο με τη φθηνή εργασία των μεταναστών θα μπορούσε να πραγματοποιηθεί. Το τελικό συμπέρασμα της εργασίας μας είναι ότι οι Αλβανοί μετανάστες του δείγματος, παρά την αφιλόξενη στάση του ελληνικού κράτους (ειδικά κατά τα πρώτα χρόνια της άφιξής τους), κατάφεραν να ενταχθούν αρμονικά στην κοινωνία και οικονομία του Ηρακλείου συνεισφέροντας θετικά στην τοπική οικονομική ανάπτυξη. Επιπρόσθετα τα θετικά συμπεράσματα της έρευνάς μας είναι κοινά με αυτά παρόμοιων ερευνών για την οικονομική συνεισφορά των Αλβανών μεταναστών που έγιναν σε άλλες πόλεις της Ελλάδας και που παρουσιάστηκαν στη θεωρητική επισκόπηση της έρευνάς μας
Digitalisering av bankbransjen
Oppgaven ser på sammenhengen mellom digitalisering og sysselsetting i bank, og hvordan digitalisering virker på sysselssetting i bankbransjen
Beyond the Hype: A Bibliometric Analysis Deconstructing Research on Digitalization
The accelerating emergent field of research addressing digitalization and related topics is complex, unstructured and hyped. Consequently, both research and practice lack a rigorous foundation of prior published research to underpin and direct future exploration into the opportunities and challenges provided by these exciting new digital technologies. This study employed a bibliometric analysis to explore extant published research within the digitalization field. We identified key articles that have enabled us to distinguish between interrelated digitalization concepts. Subsequently, we propose a taxonomy with characteristics for different levels of digitalization. The taxonomy contributes dimensions that create different commercial and organizational opportunities and challenges at various levels. The taxonomy offers a vantage point for subsequent empirical and conceptual research to extend insights on related digitalization themes, and especially those related to innovation and strategy decisions on scalability, automation, channel selection and connectivity
Beyond the Hype: A Bibliometric Analysis Deconstructing Research on Digitalization
The accelerating emergent field of research addressing digitalization and related topics is complex, unstructured and hyped. Consequently, both research and practice lack a rigorous foundation of prior published research to underpin and direct future exploration into the opportunities and challenges provided by these exciting new digital technologies. This study employed a bibliometric analysis to explore extant published research within the digitalization field. We identified key articles that have enabled us to distinguish between interrelated digitalization concepts. Subsequently, we propose a taxonomy with characteristics for different levels of digitalization. The taxonomy contributes dimensions that create different commercial and organizational opportunities and challenges at various levels. The taxonomy offers a vantage point for subsequent empirical and conceptual research to extend insights on related digitalization themes, and especially those related to innovation and strategy decisions on scalability, automation, channel selection and connectivity