No description available.

Esophageal cancer is the eighth most common cancer in the world. Cancers of the esophagus account for 3.8% of all cases of cancers, with approximately 482,300 new cases reported in 2008 worldwide. In the United States alone, it is estimated that approximately 18,000 new cases will be diagnosed in 2013, and 15,210 deaths are expected. Despite advances in surgery and chemoradiation therapy, these advances have not led to a significant increase in survival rates, primarily because diagnosis often at an advanced and incurable stage when treatment is more difficult and less successful. Accurate, objective methods for early detection of esophageal neoplasia are needed. Here, quantitative classification algorithms for high resolution miscroendoscopic images were developed to distinguish between esophageal neoplastic and non-neoplastic tissue. A clinical study in 177 patients with esophageal squamous cell carcinoma (ESCC) was performed to evaluate the diagnostic performance of the classification algorithm in collaboration with the Mount Sinai Medical Center in the United States, the First Hospital of Jilin University in China, and the Cancer Institute and Hospital, the Chinese Academy of Medical Science in China. The study reported a sensitivity and specificity of 93% and 92%, respectively, in the training set, 87% and 97%, respectively, in the test set, and 84% and 95%, respectively, in an independent validation set. Another clinical study in 31 patients with Barrett’s esophagus resulted in a sensitivity of 84% and a specificity of 85%. Finally, a compact, portable version of the high resolution microendoscopy (HRME) device using a consumer-grade camera was developed and a series of biomedical experimental studies were carried out to assess the capability of the device.

A body of work and ensuing publications covering 2000–2012 are presented, predominantly concerning studies of various cohorts of people exposed to ionising radiation. The major areas cover epidemiological and statistical studies on the Life span study (LSS) cohort of Japanese survivors of the World War II atomic-bomb attacks on Hiroshima and Nagasaki and the mortality follow-up of German uranium miners. Following the presentation of a very brief history of the effects of radiation exposure on humans, the background and context of the advances achieved by the candidate are described. The LSS provides the most studied cohort and a range of topics from cancer risks related to neutron and γ-ray doses, organ specific doses, and carcinogenesis have been explored covering about half of the candidate’s publications. The cohort of German “Wismut” uranium miners exposed to radon and other potential carcinogens, which is the largest one of its kind, has enabled the development of epidemiological models for lung and extra-pulmonary cancers. The third distinct topic relates to analyses of data on cellular radiation damage relevant to the evaluation of both diagnostic radiation characteristics and the effects on cancer patients. Other studies have considered the incidence of malignant diseases in humans injected with radium-224 and development of epidemiological models for thyroid cancer risk in areas affected by the 1986 Chernobyl accident. Fundamental contributions have been published in the application of mathematical methods for data analysis. The candidate has succeeded in going beyond the traditional statistical methods in radiation epidemiology by introduction of numerical techniques deriving from the field of information science and novel to the field. These methods, such as techniques for model selection and mitigation of strongly correlated quantities, have been presented as general tools and have demonstrated powerful results, such as in applications to data from LSS. The impact and relevance for public health of the epidemiological results is indicated by their frequent citation in recent reports by international bodies such as by the International Commission on Radiological Protection, the United Nations Scientific Committee on the Effects of Atomic Radiation, the World Health Organization (WHO) and WHO-International Agency for Research on Cancer.Several topics, from among this broad coverage of radiation epidemiological themes, the development of novel statistical techniques and their application, are highlighted. Work on distinguishing the effect of neutrons and γ-rays in the Japanese LSS data has led to progress on quantifying their relative biological effectiveness with important consequences for the health effects of modern radiation diagnostics. A technique for combining risks from several risk models, called multi-model inference, has been shown to ease the dilemma of selecting between models with very different consequences, with particular relevance for major issues of public health concern connected with radiation exposure. The Wismut cohort has revealed for the first time the response characteristics of a significant effect of working underground on prostate cancer incidence, suggesting a relation with lack of exposure to light which remains unexplained.

No description available.

No description available.

The current study examined and compared the use of Rasch measurement, common factor analysis (EFA), and confirmatory factor analysis (CFA) in establishing construct validity evidence based on internal structure with multi-item scales measuring middle and secondary students' achievement goal orientation and academic self-efficacy. 1054 complete responses were received to 18 items measuring mastery, performance-approach, performance-avoidance, and self-efficacy. Items in each subscale were first analyzed by each method as a unidimensional unit. Items were then analyzed by each method as a multidimensional unit. Results showed that when scales were analyzed individually, all three methods corroborated unidimensionality; however, when all items were analyzed together, the multi-factor model identified through EFA was not supported by the Rasch or CFA analysis. While EFA provided the best information about individual item functioning, Rasch provided important, additional information about rating scale functioning and item fit that helps diagnose poorly performing items. Results also support the use of EFA in evaluating the suitability of a scale for meeting the unidimensionality requirement of item response models. While the mastery and efficacy scales performed in a manner consistent with the motivation literature, the approach and avoidance subscales did not. Conclusions from the study include the need for better explication of conjoint use of classical and modern test theory methods in instrument development, more exposure of current and future researchers to the foundations of measurement theory, and more research about the saliency of measuring performance-avoidance.

Novel casting alloys that retain their mechanical strength at temperatures up to 300 °C are needed in order to improve automotive engine efficiency. The addition of Zr and V is a promising combination as a means of introducing the thermally stable cubic Al3ZrxV1-x nano-precipitates. In this project, the evolution of the Al3ZrxV1-x precipitates in multi-component cast aluminium alloys was characterised in a statistically significant way using small-angle X-ray scattering (SAXS). Unlike established metallurgical techniques, such as transmission electron microscopy (TEM), SAXS measures billions of precipitates in a single experiment. Two Al-6.8Si (wt.%) alloys were employed. One contained 0.30 wt.% Zr and 0.30 wt.% V and the other 0.37 wt.% Zr and 0.34 wt.% V. The alloys were cast and isothermally aged at 400 °C for times ranging from 3 to 50 h. Synchrotron SAXS was undertaken at the Diamond Light Source (DLS). Direct evaluation methods of SAXS spectrum were employed in order to extract information about the average precipitate size, precipitate size distribution and their evolution with ageing time. These results were compared with the results provided via TEM, both validating the methodology, and demonstrating the benefits and drawbacks of SAXS.From the SAXS analysis, the Guinier radius, Rg, was found to increase with ageing time from around 2 nm at 3 h to approximately 9 nm at 50 h. Precipitate volume fraction also increased from 0.11 vol.% to 0.24 vol.% for the lower solute alloy and from 0.14 vol.% to 0.33 vol.% for the higher solute one. In both alloys, the precipitate number density was observed to continuously decrease with ageing time. For the higher solute alloy, the average precipitate radius from the TEM measurements was found to be consistently smaller than Rg. Such a study is important because it extends the experimental SAXS methodology previously used only in simplified alloys to multi-component cast alloys of industrial importance. Moreover, the findings from this investigation suggest that both alloys quickly enter a stage where the precipitate growth and coarsening overlap, and the precipitate number density continuously decreases with time. Finally, this study underlines the importance of preliminary SAXS data treatment and provides an analytical guide in order to successfully characterize low volume fraction of precipitates in multi-component cast alloys.

The aim of this Master's Thesis is the study of frequency of contraargumentative connectors in Spanish, based on the quantitative analysis of these cohesive devices in argumentative texts. The theoretical part follows and draws from the works of renowned Spanish linguists and introduces the reader to the issue of discourse markers. Thus, different proposals for its definition and classification are taken in consideration, then are described the fundamental characteristics of the contraargumentative connectors. These are examined later in the practical part. Divided into chapters it offers focus on the quantitative analysis of the connectors in three corpuses which are comprised of judgments, academic writings and editorials. For greater clarity, analyses are accompanied by graphs and frequency tables. A Czech summary is added at the end of this investigation.

No description available.

Η Δικαλουταμίδη είναι γνωστό φάρμακο για τη θεραπεία του καρκίνου του προστάτη και κυκλοφορεί στην ελληνική αγορά με το εμπορικό όνομα casodex. Η διακαλουταμίδη υπάρχει σε δύο κρυσταλλικές μορφές (πολύμορφα) εκ των οποίων το πολύμορφο που εξετάζουμε (Ι) είναι αυτό που χρησιμοποιείται από τη βιομηχανία για την παραγωγή των δισκίων. Στην παρούσα εργασία αναπτύσσονται μεθοδολογίες ποσοτικού προσδιορισμού της δικαλουταμίδης Ι σε δισκία βασιζόμενες στις τεχνικές XRD (Χ Ray Diffraction), Raman και ATR (Attenuated Total Reflectance). Οι τεχνικές αυτές είναι οι πλέον κατάλληλες για τον ποσοτικό προσδιορισμό πολυμόρφων αφού οι ευρέως χρησιμοποιούμενες χρωματογραφικές τεχνικές δεν μπορούν να διακρίνουν μεταξύ των διαφορετικών κρυσταλλικών φάσεων. Για τον προσδιορισμό αυτό παρασκευάστηκαν μείγματα γνωστών αναλογιών κατά βάρος, της δραστικής και των εκδόχων, και χρησιμοποιήθηκαν για τη δημιουργία πρότυπης καμπύλης βαθμονόμησης για κάθε μία τεχνική. Οι καμπύλες βαθμονόμησης ήταν της μορφής y= a + b x. Το όριο ανίχνευσης για την ATR είναι 0,048 % wt, για την XRD είναι 0.14% wt και για τη μέθοδο FT-Raman 0.053% wt. Η εφαρμογή των εξισώσεων βαθμονόμησης σε εμπορικά δισκία των 50mg έδωσε τα ακόλουθα αποτελέσματα. Στη μέθοδο της περίθλασης ακτινών Χ η δραστική ουσία βρέθηκε να είναι 51,2 mg. Αυτή η τιμή αντιστοιχεί σε σφάλμα επί της ονομαστικής τιμής ίσο με 2,4% ενώ αντίστοιχα στη φασματοσκοπία Raman το σφάλμα της ονομαστικής τιμής βρέθηκε ίσο με 0,96% αφού η δραστική στο δισκίο μετρήθηκε και βρέθηκε να αντιστοιχεί σε 50,48 mg. Είναι ενδιαφέρον ότι ενώ η τεχνική της Attenuated Total Reflectance έδωσε ικανοποιητική καμπύλη βαθμονόμησης εντούτοις η εφαρμογή της στο εμπορικό σκεύασμα ήταν απογοητευτική και το σφάλμα βρέθηκε να είναι μεγαλύτερο του 67%. Πιθανώς η αποτυχία να οφείλεται στο μέγεθος των σωματιδίων στα κονιοποιημένα εμπορικά δισκία το οποίο μπορεί να ήταν αρκετά διαφορετικό από το αντίστοιχο μέγεθος στα πρότυπα μείγματα του εργαστηρίου.. Σύμφωνα με τα αποτελέσματα συνιστάται η εφαρμογή της φασματοσκοπίας Raman για τον ποσοτικό προσδιορισμό της δραστικής γιατί συνδυάζει μικρό όριο ανίχνευσης και πολύ μικρή απόκλιση των ποσοτικών αποτελεσμάτων των εμπορικών δισκίων από την ονομαστική τιμή του σκευάσματος. / Bicalutamide is a well known drug for prostat cancer. Bicalutamide presents two crystalline polymorphs (form I and form II) which have the same chemical composition but different internal crystal structures due to different molecular conformation and, therefore, possess different physico-chemical properties. Form I is more stable than form II, and is already used as active pharmaceutical ingredient (API) in the form of tablets, such as Caxodex, produced by AstraZeneca. Form I is the polymorph that we used in this work. X-Ray Diffraction, Raman Spectroscopy and Attenuated Total Reflectance were used for the quantitative analysis of bicalutamide I in tablets and, their results were compared to each other. These techniques are the most suitable for determination of polymorphs as opposed to the widely used chromatographic techniques that cannot differentiate between the crystalline phases. Mixtures of different ratio of API (bicalutamide I) and excipients were prepared in order to construct a calibration curve for every technique. The detection limits for all suggested methods were determined as follows: a) ATR: 0,048 % wt, b) XRD: 0.14% wt and c) FT-Raman: 0.053% wt. The constructed calibrations lines were applied in commercial tablets of 50mg strength. The API strength in the commercial tablets using the ΧRD method was found to be 51,2 mg. This corresponds to an error of 2,4% with respect to the nominal value. FT-Raman method has yielded an error of 0,96% since the API strength of the commercial tablet was found to be 50,48mg. Application of ATR’s calibration curve has yielded an error of more than 67%. Probably the failure was due to the different particle size of mixtures used for the construction of the calibration curve and those of the grounded commercial tablets Based on the obtained data it can be concluded that the most suitable technique for the quantitative determination of the API strength in bicalutamide tablets is FT-Raman since it exhibits the minimum detection limit while the error from the nominal value of the API strength in the 50mg tablets was found to be less than 1%.