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.

L'élaboration de réseaux poreux pi-conjugués par l'auto-organisation de molécules organiques, les cyclotriphosphazènes spirocycliques, a été explorée. L'étude de la stabilité des réseaux obtenus à partir du tris(o-phénylènedioxy)cyclotriphosphazène (TPP) conjointement à l'étude de la réactivité du N3P3Cl6 face à l'attaque nucléophile de différents dérivés du catéchol ont permis de définir de nouvelles cibles. Dans ce cadre, un nouveau composé, le tris(2,3-triphénylènedioxy)cyclotriphosphazène (TTPP) dans lequel le motif central est substitué par trois systèmes pi-conjugués étendus de type triphénylène a été synthétisé. Les tectons TTPP, de symétrie C3, présentent une orientation atypique des motifs aromatiques. Leur forme, analogue à celle d'une roue à aubes, leur permet d'engendrer à l'état cristallin des lacunes sous forme de deux types de nano-canaux de respectivement 6,1 Å et 8,4 Å de large et 10,7 Å et 12,4 Å de large, pouvant inclure des molécules de 1,2,4-trichlorobenzène. Ce matériau contient la plus grande porosité obtenu à partir de cyclotriphosphazènes spirocycliques à ce jour. La formation de réseaux poreux chiraux a également été réalisée à partir de tectons portant chacun trois motifs (S)-binol. Le (S,S,S)-tribinolcyclotriphosphazène ((S,S,S)-TBP) a ainsi pu être co-cristallisé avec des molécules d'o-xylène. Ainsi, des informations permettant de mieux comprendre la structure moléculaire de cyclotriphosphazènes portant des spirocycles à sept chaînons ont été obtenues. Enfin, les propriétés optoélectroniques des tectons ont été étudiées en solution. L'influence de l'agent directeur cyclotriphosphazène sur les propriétés optiques des chromophores a, en particulier, été abordée. / Elaboration of pi-conjugated networks through self-organization of spirocyclic cyclotriphosphazene molecules has been explored. The stability of the networks built from described tris(o-phenylenedioxy)cyclotriphosphazene (TPP) jointly with the study of the reactivity of N3P3Cl6 undergoing nucleophilic attack by catechol derivatives allowed to design new tectons. In this context, a new tris(2,3-triphenylenedioxy)cyclotriphosphazene (TTPP) compound embedding a central hub substituted by pi-conjugated triphenylene unit has been synthesized. TTPP tectons exhibits a particular shape with specific orientation of aromatic units. Their paddle-wheel like shape allows the elaboration of a porous network having two types of nano-tunnels of respectively 6.1 Å and 8.4 Å large and 10.7 Å and 12.4 Å large. This material has the biggest channel size described for network build from spirocyclic cyclotriphosphazenes and inclusion compounds with 1,2,4-trich lorobenzene molecules were made. Elaboration of chiral porous network from tectons constituted by three (S)-binol units has also been realized. Tribinolcyclotriphosphazene has been co-cristallized with o-xylene molecules. Thus, useful informations on seven-membered spirocyclic cyclotriphosphazene molecular structure have been obtained. Finally, tectons opto-electronic properties have been studied in solution. Influence of the cyclotriphosphazene directing agent on optical chromophore properties has been a particular matter of attention.