Selenium (Se), an essential trace element, plays an important role in the normal function of a number of Se-dependent biological processes. Many studies have demonstrated that selenium deficiency in the body may contribute to an increased risk for certain neoplastic diseases (including colonic carcinoma, gastric carcinoma, pulmonary carcinoma and prostate carcinoma), as well as diseases of the cardiovascular, osseous, nervous systems and retardation of bone formation. However, at higher concentrations Se is cytotoxic. For these reasons it is desirable to have a means of monitoring selenium concentration in humans. The feasibility of measuring selenium in humans using the in vivo neutron activation analysis (IVNAA) technique was studied. For this purpose human hand tissue equivalent phantoms were prepared with varying amounts of selenium and irradiated by a low energy neutron beam produced by the 7Li(p,n)7Be reaction by employing the high beam current Tandetron accelerator. The counting data saved using the 4π NaI(TI) detection system in anticoincidence, coincidence and singles modes of detection were analyzed. The selenium was detected via the neutron capture reaction, 76Se(n,γ)77mSe, whereas calcium was detected through the 48Ca(n,γ)49Ca reaction. The peak areas of Se and Ca were computed and the Se concentrations were normalized to the Ca concentrations for various time segments of detection. The calibration lines were drawn between Se/Ca concentration and Se/Ca counts ratio. The minimum detection limits (MDL) were obtained and the inverse variance weighted mean value of MDL was finally calculated for three time segments. During the analysis of counting data it was also found that 18O is activated in water phantoms and becomes short lived radioactive 19O having T1/2=26.9 s. To the author’s best knowledge, this study for the first time presents the MDL value in terms of Se/Ca concentration for the human hand bone equivalent phantom obtained from in vivo neutron activation analysis and these results will provide a good basis for future investigations. / Thesis / Master of Science (MSc)

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京都大学 / 新制・課程博士 / 博士(理学) / 甲第23687号 / 理博第4777号 / 新制||理||1684(附属図書館) / 京都大学大学院理学研究科数学・数理解析専攻 / (主査)教授 長谷川 真人, 教授 牧野 和久, 准教授 照井 一成 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

This thesis is dedicated to exploring effective person counting using sensors, an important technology in areas such as space optimization. The main challenges in this field include issues with accuracy and reliability. The goal of this thesis is to explore and identify the most effective sensor type for counting individuals in a space. To address these problems, three main types of sensors were used: ultrasound, infrared, and laser. Each sensor was tested and the results show that ultrasound sensors generally had the highest reliability, although no sensor achieved complete accuracy. The study underscores the need for further development and the potential for combining technologies to enhance accuracy and reliability in person counting systems. / Denna uppsats ägnas åt undersökning av effektiv personräkning med hjälp av sensorer, en viktig teknik inom områden såsom optimering av lokalanvändning. Huvudproblemen inom området inkluderar utmaningar med noggrannhet och pålitlighet. Målet med denna uppsats är att undersöka och identifiera den mest effektiva sensortypen för personräkning i en lokal. För att lösa dessa problem användes tre huvudtyper av sensorer: ultraljud, infraröd och laser. Varje sensor testades och resultaten visar att ultraljudssensorer överlag hade högst pålitlighet, även om ingen av sensorerna uppnådde fullständig noggrannhet. Studien understryker behovet av vidare utveckling och potentialen för att kombinera tekniker för att förbättra noggrannheten och tillförlitligheten i personräkningssystem.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Photophysical properties of an array of various polyaromatic hydrocarbons were benchmarked with B3LYP, M06 and B97D methods coupled with Pople and CEP-31G(d) basis sets. Results from the benchmark show the importance of diffuse basis sets when modeling the electronic properties of highly conjugated systems and provide qualitative reliable accuracy with certain levels of theory. B97D and M06 are applied to modeling pyrene adducts governed by non-covalent interactions in both gaseous and condensed states to reproduce experimental spectra. DFT calculations with both B97D and M06 functionals show qualitatively and quantitatively that pyrene dimer is a stronger π–base as compared to its monomer. Binding energies coupled with MEP, PCA and Qzz results show that the difference in π-basicity of the monomer and dimer impacts the supramolecular chemistry involved in adducts formed with super π-acidic silver cyclometallic trimer (CTC). Non-covalent interactions between coinage metal CTCs and ammonia/phosphine substrates is reported. Interactions between these substrates and the facial plane of the π-rich gold CTC reveal a novel interaction, where the typical Lewis acid/base roles are reversed for the substrates. Adducts formed through this type of interaction define typical Lewis bases like ammonia and phosphine as Lewis acids, wherein the partially positive hydrogens coordinate to the metallo-aromatic center through dipole-quadrupole interactions. Interactions of ammonia at the side positions is shown to heavily impact the Lewis basicity of the CTC facial plane leading to similar interactions exhibited by the ammonia-gold CTC adducts. Structural and electronic properties of the adducts modeled are examined.