This thesis concerns the development of semiochemical identification expertise and methodology at the University of Pretoria. The Eucalyptus snout beetle Gonipterus scutellatus was used as a model insect in developing these methods, firstly because it is a known pest in the Eucalyptus forestry industry of South Africa. Secondly, nothing is known about its chemical ecology and lastly, it is a relatively large insect that is easily worked on. Three main techniques were used namely: Electroantennography (EAG), Gas Chromatography Electroantennography Detection (GC-EAD) and Gas Chromatog- raphy Mass Spectrometry (GC-MS). EAG was used to difierentiate and identify certain Eucalyptus species that were expected to contain compounds that may function as either kairomones or allomones for G. scutellatus. The EAG process revealed that G. scutellatus responds more intensely to damaged Eucalyptus leaves as compared to undamaged leaves. The crushed foliage of the known hosts Eucalyptus globulus and E. viminalis gave larger responses than the crushed foliage from a known non-host E. citriodora. We sampled the volatiles from the crushed foliage of these three species and tentatively identified sixteen compounds from the E. globulus volatile profile that was antennally active for G. scutellatus females. The presence of these volatiles were subsequently investigated for E. viminalis and E. citriodora. The green leaf volatiles, (Z)-3 hexenyl acetate, (Z)-3-hexen-1-ol and (E)-2-hexenal and aromatic compounds, 2-phenylethanol, benzyl acetate and ethylphenylacetate often gave larger responses than the terpenes such as α-pinene, β-pinene and camphene. Crushed E. globulus leaves contained 2-phenyl ethanol, benzyl acetate, ethylphenylacetate, eucalyptol, α-pinene, (Z)-3 hexenyl acetate, (Z)-3-hexen-1-ol and (E)-2-hexenal that were antennally active. The E. viminalis profile had very little 2-phenylethanol and virtually no benzyl acetate. The E. citriodora volatile profile contained very little (Z)-3-hexen-1-ol, (E)-2-hexenal, 2-phenylethanol, benzyl acetate and ethylphenylacetate. These compounds may influence the host selection behaviour of G. scutellatusfemales. These volatiles can be tested in a behavioural bioassay in order to determine their effect on the Eucalyptus snout beetle G. scutellatus. / Dissertation (MSc)--University of Pretoria, 2010. / Chemistry / unrestricted

This work is focused on verifying the permeability and olfactometric assessment of emissions from selected polymeric foam materials and foam rubber. The olfactometric assessment is based on the analysis of identified and identified volatile organic compounds. The research was conducted by taking samples of the emissions from a small-space sampling chamber. Emissions were analyzed by gas chromatography with mass spectrometry and their assessment by the assessor was performed by dynamic olfactometry. The work was supplemented by designing its own experimental procedure of mechanical stress of foam materials and changes in climatic conditions in the air-conditioning chamber in connection with release of emissions. Standard testing procedures according to European standards (EN ISO 16000-9, ČSN 13725 and EN ISO 7231) have been used to test these properties. The aim of the work is to verify selected properties of polymeric foam materials ? permeability and olfactometric assessment related to the analysis of volatile organic compounds. It also involves permeability is a change in breathability, depending on mechanical stress and release of emissions influencing given properties in terms of time, mechanical stress, and changing climatic conditions.

京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第20038号 / 地環博第154号 / 新制||地環||31(附属図書館) / 33134 / 京都大学大学院地球環境学舎環境マネジメント専攻 / (主査)教授 梶井 克純, 准教授 真常 仁志, 准教授 田中 周平 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM

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京都大学 / 新制・課程博士 / 博士(農学) / 甲第24657号 / 農博第2540号 / 新制||農||1098(附属図書館) / 学位論文||R5||N5438(農学部図書室) / 京都大学大学院農学研究科森林科学専攻 / (主査)准教授 石原 正恵, 教授 德地 直子, 教授 井鷺 裕司, 教授 北島 薫 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Unexpected high mutations detected in new emerging variants of concern (VOCs) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), especially in the case of omicron, raises concerns and efforts to understand their evolutionary trajectory. Several hypotheses have been discussed in literature to conceptualize the source of their emergence, including intra-host viral evolution in immunocompromised patients. These patients grant opportunities for the emergence of new variants through a persisting virus winning against host immunity, and selection for viral mutations driven by treatment interventions. VOCs have in common high mutation rate exceeding the average rate of 1-2 mutations per month. Not many studies have investigated the evolutionary rate of SARS-CoV-2 in immunocompromised candidates. Therefore, the purpose of this study is to reveal potential mechanisms underlying the emergence of VOCs by exploring substitution rate of SARS-CoV-2 genomes from surveyed COVID-19 immunocompromised patient’s studies. First, SARS-CoV-2 genome sequences were collected at sequential time series throughout host infection, which were reported in the previous studies. Filtration criteria was applied to reanalyze patients with prolonged infection documented for ≥ 2 months, and comprehensive sequenced samples for ≥ 6 time points. Then, phylogenetic analysis was conducted using Nextclade (https://clades.nextstrain.org/), followed by mutation rate analysis using two substantial similar approaches to calculate the rate in i) substitutions per month and ii) substitutions per site (per year). The mutation tendency of SARS-CoV-2 in immunocompromised hosts was compared to reported VOCs, particularly to omicron. The highest observed mutation rate accounted for approximately 2.2 mutations per month, which is higher than the average rate. High mutation rate was due to prolonged infection and selection pressure by treatment interventions (i.e., convalescent plasma and antibodies). Here, higher rate of intra-host viral evolution in immunocompromised patients is detected, potentially leading to the emergence of VOC. Hence, this research highlights the need for sequencing efforts in high-risk individuals, updating treatment strategies along with further analysis on adaptive mutants pronounced due to intra-host evolution. Together, such findings provide an ultimate synergy for future public health guidelines and infection control measures.

This thesis describes the preparation and characterization of manganese oxide catalysts and their application in the oxidation of acetone, a typical volatile organic compound (VOC), and ozone decomposition. This topic is of great value because of environmental concerns of the elimination of the harmful VOCs and ozone. Manganese oxide was chosen because it is a well-known complete oxidation catalyst for VOCs and also an active catalyst for ozone decomposition. Two cases of studies were carried out in this work. The first study involved the oxidation of acetone using ozone on silica- and alumina-supported manganese oxide catalysts deposited on aluminum oxide foam substrates. The characteristics of the catalysts were determined through various techniques, including x-ray diffraction (XRD), x-ray absorption spectroscopy (XAS), Brunauer-Emmett-Teller (BET) surface area analysis, temperature-programmed reduction (TPR), and oxygen chemisorption. The use of these techniques allowed better understanding of the nature of the catalysts. Activity tests were carried out in the acetone oxidation reaction and it was found that the usage of ozone substantially reduced the oxidation temperature. Steady-state in situ Raman spectroscopy was also carried out to better understand the mechanism of the acetone oxidation reaction using ozone. The second study involved an investigation of structural and electronic properties of manganese centers of the MnOx/SiO2 and MnOx/Al2O3 catalysts during the ozone decomposition reaction using in situ x-ray absorption spectroscopy (XAS). The number of surface active sites was again determined through TPR and oxygen chemisorption measurements. The performance of the catalysts with different loadings and supports were also compared. / Master of Science

運用科學知識在當代環境管制政策幾乎已屬常態。然而，科學卻不一定能有效解決環境污染問題。本研究探討雲林六輕石化廠區的揮發性有機物（VOCs）空氣污染問題，發現運作二十多年的六輕，其排放之VOCs數值，至今尚未釐清，但企業仍不斷擴廠，引發當地健康風險問題；同時，國光石化的環評中，PM2.5（細懸浮微粒）引發重大政治爭議，民間提出對抗性科學論述影響決策方向，後續，更促成相關管制法規通過。 在上述管制科學爭議中，本文採用新政治科學社會學所提供的制度、網絡與權力，與環境決策知識建構的途徑觀點，探討雲林石化廠區所排放的揮發性有機物（VOCs）、懸浮微粒（PM2.5）相關之管制科學爭議。運用次級資料分析法、田野調查以及深入訪談法，嘗試分析強調科學循證作為基礎的管制政策，何以仍落入管制失靈的窘境？本文探討兩個個案，其不同調的科學數字如何依循管制制度生產、傳遞及運用？其中，VOCs排放數字如何被各個政治行動者賦予政治性意涵，進而延宕政府管制的能力？甚而導致府際間嚴重衝突？而PM2.5的對抗性科學論述是如何被生產、傳遞乃至公共化？相關之政策網絡如何有效地將PM2.5的管制政策推入政治議程中，成為正式法規的一環？ 本研究發現，在VOCs個案中，基於污染物的特性、石化廠區的龐大營運複雜度、以及企業為管制資訊之主要來源等因素，使VOCs排放具有相當大的科學不確定性。不過，現行制度將這些科學不確定性切割成一場又一場對於企業資訊的審查，對於掌握確切污染狀況極其有限。在PM2.5個案中，在幾個重大政策窗事件出現之前，民間社會已有一定的知識建構基礎。而重大政策窗事件如六輕工安大火、國光石化興建以及2011年總統選舉等，促成不同社會網絡連結，協助、生產出對抗性論述，並結合公眾媒體的廣泛傳播特性，將相關科技風險知識公共化，終使得PM2.5管制法案成為正式規範之一。 / Scientific knowledge has been commonly employed for making environmental regulatory policies. This thesis aims at analyzing the contamination problems resulted from Volatile Organic Compounds (VOCs) released by the Six Naphtha Cracking Complex; it is discovered that the emission of VOCs remains a mystery after two decades of operation. However, the industrial expansion plan continues and has done a severe environmental and health destruction to the local community. Meanwhile, PM2.5, Fine Particulate Matters also triggered political controversies in the Environmental Impact Assessment process of Kuokuang Petrochemical Plant, the Eighth Naphtha Cracking Project(8th naphtha). The civil society has raised the opposing argument on the PM2.5 matter in terms of health impact, thereby influencing the direction of policy making and passing the regulations. In light of the controversies of regulatory science, this thesis adopts the perspective of New Political sociology of Science (NPSS), which substantiates the approach of institution, network and power, and other aspects of knowledge construction to analyze the emission of VOCs and PM2.5 in the petrochemical field. Moreover, secondary data, field research, and in-depth interviews are utilized to analyze these regulatory predicaments. It is discovered in the cases of VOCs, the scientific uncertainty is composed of the characteristics of VOCs, the complexity of petrochemical plant’s operations and the main regulatory information is generated by industries. Nevertheless, the regulatory institution just divided the scientific uncertainty into the tremendous conferences which peer-reviewed the information from industries. Furthermore, this regulatory institution hinders the true conditions of pollution from being known. In the meantime, in terms of PM2.5, the general public has had a solid knowledge pertaining to the critical national matters, such as several fire disasters of 6th naphtha, the policy of 8th naphtha, and the presidential election in 2011. Moreover, these policy windows promote the connection of social network and assistance, and accordingly generate the opposing discourse. The technology risk-related knowledge has also been conveyed by the mass media, thus ultimately enacting the PM2.5.

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