Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 99-108).

Thesis--Uppsala. / In Periodical Room.

O benzeno é um solvente comprovadamente cancerígeno e, para substâncias com tal característica, não há limites de exposição considerados seguros. Em vista disso, as discussões internacionais e nacionais visam a diminuir, cada vez mais, os níveis de exposição ocupacional permitidos. O ácido trans, trans-mucônico (ttAM) , um produto de biotransformação do benzeno, tem sido preconizado como um bioindicador sensível da exposição ao solvente. Este trabalho foi desenvolvido com o propósito de validar método capaz de detectar o ttAM em urina de indivíduos expostos ao benzeno, bem com estabelecer o melhor período de coleta das amostras. A técnica escolhida foi a cromatografia líquida de alta eficiência (CLAE) com coluna de fase-reversa, Lichrosorb RP 18, e detector de ultra-violeta. O método mostrou-se linear entre 0,2 a 5,0 mg/L (r2 = 0,9943). Os limites de detecção e de quantificação obtidos foram, respectivamente, 0,1 e 0,2 mg/L. A porcentagem de recuperação absoluta média foi de 77,1% e de inexatidão de 27,9%. Os coeficientes de variação médios foram, para a precisão intra-ensaio 7,7 % e, para a interensaio 10,6%. O analito permaneceu estável na matriz por um período de 6 semanas para a concentração de 0,2 mg/L e de 15 semanas, para a 2,0 mg/L, se armazenada em freezer (-20°C) e por até dez dias sob refrigeração (4°C) para os adicionados de 0,2, 2,0 e 5,0 mg/L. Com estes resultados, a validação foi considerada satisfatória. O valor médio obtido nas amostras de trabalhadores ocupacionalmente expostos no final da jornada de trabalho foi de 0,81 mg/g creatinina (mediana=0,62 mg/g creatinina). Estes resultados foram superiores e estatisticamente diferentes (p=0,025) daqueles encontrados em amostras do início da jornada e do dia seguinte, mostrando ser o final da jornada o período que melhor reflete a exposição do dia de trabalho. / Benzene is a carcinogenic chemical used in many plants. The national and international discussions aim to low more and more the permitted occupational exposure limit to benzene, although in fact, there is no safe limit to carcinogens. The trans, trans-muconic acid (ttMA), a benzene metabolite, has been recommended as a sensitive bioindicator in the biological monitoring of workers exposed to this solvent. This work was developed in order to validate a method for ttMA analysis in samples of benzene-exposed workers as well as to establish the best sample collecting time. The chosen technique was the high pressure liquid chromatography with reverse-phase column, Lichrosorb RP 18, and UV detection. A linear relationship (r2 =0.9943) was observed in the range from 0.2 to 5.0 mg/L. The detection and quantification limits were respectively 0.1 and 0.2 mg/L. The average recovery was 77.1 % and the inaccuracy (bias) was 27.9 %. Precision, evaluated by variation coefficient, were 7.7 % (intraassay) and 10.6 % (inter-assay). The ttMA remained stable in the matrix during a period of six weeks for the 0.2 mg/L samples and fifteen weeks for the 2.0 mg/L samples, in both cases when stored at - 20°C. In 0.2, 2.0 and 5.0 spiked samples no significant differences were found when conserved at 4°C for ten days. In the occupationally exposed workers, ttMA values were significantly higher in post-shift samples (p = 0.025) than in pre-shift or in those collected in the following day. These results reveal that the end of the shift is the best period to take urine samples for benzene biomonitoring.

[No abstract submitted] / Science, Faculty of / Physics and Astronomy, Department of / Graduate

No description available.

No description available.

No description available.

In the thesis, the development of asymmetric organocatalytic [3+3] sequences for the assembly of aminocyclitols is described. A water-based Wittig reaction was developed in order to produce the key enal-based starting materials, which were otherwise difficult to obtain commercially and synthetically. The enals derived from the Witig reaction were employed in the synthesis of both natural products and synthetic analogs of compounds in the amaryllidaceae family. The [3+3] Michael-aldol sequence described herein provided regio-, diastereoand enantioselective access to the core of the various targeted molecules, containing 3 to 4 defined stereocenters. The sequence was optimized via manipulation of the structures of both the organocatalyst and base used leading to increased selectivity and yield. Complete total synthesis of the natural product (+)-trans-dihydrolycoricidine was achieved using the optimized organocatalytic Michael-aldol sequence. The most effective catalyst/base combination for this synthesis was found to be a comercial diphenylsilylprolinol ether and quinidine, which led to a dramatic reduction in the number of synthetic steps taken to the final product, and highest yield, when compared to other reported approaches: in 9 chemical steps, 12% overall yield and 98% e.e. were achieved. Two non-natural analogues were also synthesized using this methodology in order to probe the minimum pharmacophore of the amaryllidaceae derivatives, as they are known to express anti-viral and anti-cancer activity for certain cell lines. (+)-3- Deoxydihydrolycoricidine containing 4 chiral centers, was synthesized via the same [3+3] Michael-aldol sequence as the natural product in 6 steps with 15% yield and >99% e.e. Similarly, (+)-trans-3-epidihydrolycoricidine was obtained in 6 steps, 27% yield and >99% e.e. The biological activity of these derivatives is yet to be examined. This highly effective method for the preparation of chiral aminocycllitols can be generalized toward the synthesis of numerous targets, which will be the focus of future research. / Thesis / Doctor of Philosophy (PhD)

This thesis examines six trans feminine informants in New York City's experiences of oppression, trans-misogyny, femi-negativity, racism, and classism, as well as their experiences of community support, conflicts and resistance practices through the lens of the term sisterhood and the practice of sisterhooding. Focus has also been placed on the informant's views on allyship and coalition, and their relationship to other communities, such as the trans masculine community. The research has been conducted through in-depth, semi-structured, qualitative interviews with six trans feminine activists in New York City. The informant group was heterogenous in regards to age, race/ethnicity, as well as in regards to where in the city they resided and which parts of the movement they were engaged in. My findings follow Jenny Gunnarsson Payne's (2006) theory on sisterhood as an empty signifier, as my informants had different definition's of the term and concept of sisterhood, and while all of them expressed ambivalences towards the term and concept, they also all used the term to varying degrees. Several saw advantages in using the term to describe kinship and solidarity between trans feminine people. The participating informants in the study listed several different conflicts within trans feminine movements. Many of them were generally skeptical to conflicts, especially to those related to cattiness, competition, language and terminology – sentiment's which I agree with, albeit with the addition, which some of my informant's also stressed, that certain conflict's regarding differences in oppressions related to intersectional hierarchies, may be necessary. In the concluding chapter I argue for an understanding of trans-sisterhood based both on an understanding of similarities and difference's in experience and an understanding of solidarity that prioritizes the voices, perspectives and leadership of the most marginalized. My informant's described grave street harassment, employment discrimination and experiences of desexualization from gay/queer men and hypersexualization from so-called tranny chasers. Because of the lack of previous research on trans femininities from the perspective of an understanding of the specific oppressions of trans-misogyny and femi-negativity, this thesis has had a broad, rather then detailed, perspective and following in the foot steps of Julia Serano (2007) argues for an analysis on the position of trans women and other trans femininities beyond the gender neutral category of transgender. A majority of my informants sharp statements on the subordination of trans femininity to trans masculinity supports my argument for the need of more research in the field of trans femininity studies with perspectives from both transgender studies and critical femininity studies. / Genom djupintervjuer undersöker uppsatsen sex olika transfeminina informanter i New Yorks erfarenheter av förtryck, trans-misogyni, femi-negativitet, rasism och klassism, såväl som deras erfarenheter av stöd, konflikter och motståndspraktiker, vilket sker genom ett undersökande av deras inställning till termen systerskap och den systerskapande praktiken. Fokus har också legat på informanternas syn på allierade, koalitioner och deras relation till andra grupper, som till exempel transmaskulina personer. För att fånga in en intersektionell bredd av erfarenheter var informantgruppen heterogen i förhållande till ålder, “ras”/etnicitet, samt i förhållande till var de bodde i staden och vilka delar av rörelsen de var engagerade i. Informanterna beskrev grova erfarenheter av trakasserier på gatorna och diskriminering på arbetsmarknaden, samt erfarenheter av hypersexualisering från så kallade tranny chaser's och avsexualisering från homosexuella och queera män. I linje med Jenny Gunnarsson Payne's (2006) teori om systerskap som tom signifikant, hade mina informanter många olika definitioner av begreppet systerskap, och medan många av dem uttryckte ambivalenser i förhållande till termen, använde sig alla av begreppet i varierande grad. Flera av dem såg stora fördelar i att använda termen för att beskriva samhörighet och solidaritet mellan transfeminina. Mina informanter listade flera olika konflikter inom de transfeminina rörelsen och var allmänt skeptiska till konflikter, framförallt till de som handlade om elaka attityder, tävlande, språk och terminologi – vilket jag håller med dem om, med tillägget, som en del informanter också tydliggjorde, att visa konflikter gällande intersektionella hierarkier kan vara nödvändiga. Jag argumenterar  för en förståelse av trans-systerskap som baseras både i en förståelse av likheter och skillnader i erfarenheter sam i en förståelse av solidaritet som prioriterar perspektiven och ledarskapet av de mest marginaliserade rösterna. Uppsatsen har ett brett perspektiv eftersom det tidigare gjorts väldigt lite forskning om transfemininiter utifrån den specifika förståelsen av trans-misogyni och femi-negativitet. I likhet med Julia Serano (2007) argumenterar jag för ett analyserande av transkvinnors och andra transfemininas situation bortanför trans som könsneutral kategori och får stöd i majoriteten av mina informanters skarpa uttalanden om den hierarkiska underordningen av transfemininitet gentemot transmaskulinitet. Slutligen menar jag att det behövs mer forskning inom fältet transfemininitetsstudier med perspektiv både från kritiska femininitetsstudier och transstudier.

Fault scarps cutting alluvial deposits define the present-day eastern boundary of Basin and Range faulting in Trans-Pecos Texas. These faults are found in the Salt Basin graben north of Van Horn, Texas, and its southerly extensions along Lobo Valley and Michigan Draw. Discontinuous and en echelon Quaternary fault scarps quickly die out to the south on the eastern side of the graben but become more continuous and develop larger displacements (up to 6 meters) along the west side of Salt Basin at the base of Sierra Diablo. The orientation of the more than one hundred Quaternary down-to-the-basin fault scarps and photolineaments appears to be controlled by pre-existing structural zones of weakness. The preferential alignment of Quaternary (Holocene?) fault scarps along the western side of the graben, the westward shifting of playa lakes and the preferred orientation of giant desiccation polygons show that the graben floor is subsiding more rapidly along the western margin. These faults also separate fresh from saline ground water. Four transverse structural lineaments crossing the northern portion of Salt Basin graben were mapped by P.B. King (1948, 1965) and M. Wiley (1970). A fifth zone, trending east-west between the Babb flexure and Bitterwell Mountain is proposed in this thesis. A tectonic origin is suggested by the orientation of the scarps and the proximity of the Mayfield fault scarps to the estimated epicenters of the 1931 Valentine earthquake. The frequency of small earth tremors felt by the residents of the basin and recorded by temporary seismograph stations indicate tectonic adjustments are presently occurring. / text