This article examines early twentieth-century British "Uranian" same-sex sexualities as a distinct entity from other labels for homosexuality. British sexologists, feminists, and other radical socialist/anarchist reformers invoked scientized versions of mysticism and Asian religions to conceptualize different, though intersecting, meanings for the Uranian. Historians of sexuality, however, tend to conflate the term "Uranian" with the other various and conflicting medico-scientific concepts circulating at the time, such as "homosexual," "sexual invert," and "intermediate sex." Overstating the slippage between terms, however, obscures the significance of Uranianism in the history of same-sex eroticism, and reinforces a dichotomy between spirituality and modernity. The Uranian discourses examined here epitomize a "progressive" historical moment that elaborated the scientific origins for the spirit, soul, and a divine will in the constitution of modern sexual/spiritual subjects. In many ways, Uranianism challenged the late nineteenth-century medical-sexological discourses that demarcated the homosexual as a pathological "type" by creating a more fluid understanding of sexuality through the interplay of Edwardian critiques of scientific materialism with New Age ideas about the mind, psyche, and spirituality. That is not to suggest that Uranianism offered an "alternative" (homo)sexuality that was disentangled from pathological discourses; on the contrary, the Uranian discourses implicitly consolidated the "homosexual type." Tracing the genealogy of Uranian sexuality through three case studies illuminates a modern moment when reformers attempted to create fluid sexualities. We find that Uranianism complicates our understandings about the supposedly dominant role of medical-scientific discourses in the construction of early twentieth-century British (homo)sexuality.

This article examines early twentieth-century British "Uranian" same-sex sexualities as a distinct entity from other labels for homosexuality. British sexologists, feminists, and other radical socialist/anarchist reformers invoked scientized versions of mysticism and Asian religions to conceptualize different, though intersecting, meanings for the Uranian. Historians of sexuality, however, tend to conflate the term "Uranian" with the other various and conflicting medico-scientific concepts circulating at the time, such as "homosexual," "sexual invert," and "intermediate sex." Overstating the slippage between terms, however, obscures the significance of Uranianism in the history of same-sex eroticism, and reinforces a dichotomy between spirituality and modernity. The Uranian discourses examined here epitomize a "progressive" historical moment that elaborated the scientific origins for the spirit, soul, and a divine will in the constitution of modern sexual/spiritual subjects. In many ways, Uranianism challenged the late nineteenth-century medical-sexological discourses that demarcated the homosexual as a pathological "type" by creating a more fluid understanding of sexuality through the interplay of Edwardian critiques of scientific materialism with New Age ideas about the mind, psyche, and spirituality. That is not to suggest that Uranianism offered an "alternative" (homo)sexuality that was disentangled from pathological discourses; on the contrary, the Uranian discourses implicitly consolidated the "homosexual type." Tracing the genealogy of Uranian sexuality through three case studies illuminates a modern moment when reformers attempted to create fluid sexualities. We find that Uranianism complicates our understandings about the supposedly dominant role of medical-scientific discourses in the construction of early twentieth-century British (homo)sexuality.

This article examines early twentieth-century British "Uranian" same-sex sexualities as a distinct entity from other labels for homosexuality. British sexologists, feminists, and other radical socialist/anarchist reformers invoked scientized versions of mysticism and Asian religions to conceptualize different, though intersecting, meanings for the Uranian. Historians of sexuality, however, tend to conflate the term "Uranian" with the other various and conflicting medico-scientific concepts circulating at the time, such as "homosexual," "sexual invert," and "intermediate sex." Overstating the slippage between terms, however, obscures the significance of Uranianism in the history of same-sex eroticism, and reinforces a dichotomy between spirituality and modernity. The Uranian discourses examined here epitomize a "progressive" historical moment that elaborated the scientific origins for the spirit, soul, and a divine will in the constitution of modern sexual/spiritual subjects. In many ways, Uranianism challenged the late nineteenth-century medical-sexological discourses that demarcated the homosexual as a pathological "type" by creating a more fluid understanding of sexuality through the interplay of Edwardian critiques of scientific materialism with New Age ideas about the mind, psyche, and spirituality. That is not to suggest that Uranianism offered an "alternative" (homo)sexuality that was disentangled from pathological discourses; on the contrary, the Uranian discourses implicitly consolidated the "homosexual type." Tracing the genealogy of Uranian sexuality through three case studies illuminates a modern moment when reformers attempted to create fluid sexualities. We find that Uranianism complicates our understandings about the supposedly dominant role of medical-scientific discourses in the construction of early twentieth-century British (homo)sexuality. / Arts, Faculty of / History, Department of / Graduate

Neste trabalho foi estabelecido um procedimento para determinação da razão isotópica 238U/235U em amostras de UF6, utilizando-se um espectrômetro de massas quadrupolar com ionização por impacto eletrônico e detecção de íons por copo de Faraday ou multiplicador de elétrons. Para tanto, o espectrômetro foi otimizado, determinando-se os parâmetros para a fonte de íons que proporcionassem a maior intensidade de corrente iônica, mantendo o pico de forma arredondada, para a massa correspondente ao isótopo mais abundante; a resolução que reduzisse os efeitos não lineares e o número de ciclos analíticos que reduzisse a incerteza nos resultados. O processo de medição foi caracterizado quanto: aos efeitos de discriminação de massa, linearidade e efeito memória. A discriminação de massas mostrou ser linearmente dependente da pressão da amostra no tanque de expansão nas faixas de 0,15 a 0,30 mbar e de 0,30 a 0,40 mbar. O espectrômetro mostrou-se linear na medição de razões isotópicas entre 0,005 e 0,045. Os fatores de memória para a fonte de íons e para o sistema de introdução são, respectivamente, 1,000 ± 0,001 e 1,003 ± 0,003; o primeiro pode ser desprezado e o segundo eliminado por procedimentos de lavagem do sistema de introdução. O trabalho apresenta, em sua parte final, um roteiro para as análises de amostras de UF6 e a determinação das incertezas nos resultados. / In the present work a procedure for determination of the isotopic ratio 238U/235U in UF6 samples was established using a quadrupole mass spectrometer with ionization by electron impact and ion detection by Faraday cup or electron multiplier. For this, the following items were optimized in the spectrometer: the parameters in the íon source that provided the most intense peak, with good shape, for the corresponding mass of the most abundant isotope; the resolution that reduced the non linear effects and the number of analytic cycles that reduced the uncertainty in the results. The measurement process was characterized with respect to the effects of mass discrimination, linearity and memory effect. The mass discrimination showed to be linearly dependent of the sample pressure in the batch volume, for the pressure ranges from 0.15 to 0.30 mbar and from 0.30 to 0.40 mbar. The spectrometer was shown linear in the measurement of isotopic ratios between 0.005 and 0.045. The memory factor for the íon source and for the introduction system were, respectively, 1.000 ± 0.001 and 1.003 ± 0.003; the first one can be ignored, the second one can be eliminated by washing the batch volume with the new sample. A methodology for routine analysis of UF6 samples and the determination of the uncertainties were set up in details as well.

Neste trabalho foi estabelecido um procedimento para determinação da razão isotópica 238U/235U em amostras de UF6, utilizando-se um espectrômetro de massas quadrupolar com ionização por impacto eletrônico e detecção de íons por copo de Faraday ou multiplicador de elétrons. Para tanto, o espectrômetro foi otimizado, determinando-se os parâmetros para a fonte de íons que proporcionassem a maior intensidade de corrente iônica, mantendo o pico de forma arredondada, para a massa correspondente ao isótopo mais abundante; a resolução que reduzisse os efeitos não lineares e o número de ciclos analíticos que reduzisse a incerteza nos resultados. O processo de medição foi caracterizado quanto: aos efeitos de discriminação de massa, linearidade e efeito memória. A discriminação de massas mostrou ser linearmente dependente da pressão da amostra no tanque de expansão nas faixas de 0,15 a 0,30 mbar e de 0,30 a 0,40 mbar. O espectrômetro mostrou-se linear na medição de razões isotópicas entre 0,005 e 0,045. Os fatores de memória para a fonte de íons e para o sistema de introdução são, respectivamente, 1,000 ± 0,001 e 1,003 ± 0,003; o primeiro pode ser desprezado e o segundo eliminado por procedimentos de lavagem do sistema de introdução. O trabalho apresenta, em sua parte final, um roteiro para as análises de amostras de UF6 e a determinação das incertezas nos resultados. / In the present work a procedure for determination of the isotopic ratio 238U/235U in UF6 samples was established using a quadrupole mass spectrometer with ionization by electron impact and ion detection by Faraday cup or electron multiplier. For this, the following items were optimized in the spectrometer: the parameters in the íon source that provided the most intense peak, with good shape, for the corresponding mass of the most abundant isotope; the resolution that reduced the non linear effects and the number of analytic cycles that reduced the uncertainty in the results. The measurement process was characterized with respect to the effects of mass discrimination, linearity and memory effect. The mass discrimination showed to be linearly dependent of the sample pressure in the batch volume, for the pressure ranges from 0.15 to 0.30 mbar and from 0.30 to 0.40 mbar. The spectrometer was shown linear in the measurement of isotopic ratios between 0.005 and 0.045. The memory factor for the íon source and for the introduction system were, respectively, 1.000 ± 0.001 and 1.003 ± 0.003; the first one can be ignored, the second one can be eliminated by washing the batch volume with the new sample. A methodology for routine analysis of UF6 samples and the determination of the uncertainties were set up in details as well.

<div>There is an increasing interest in future space missions devoted to the exploration of key moons in the Solar system. These many different missions may involve libration point orbits as well as trajectories that satisfy different endgames in the vicinities of the moons. To this end, an efficient design strategy to produce low-energy transfers between the vicinities of adjacent moons of a planetary system is introduced that leverages the dynamics in these multi-body systems. Such a design strategy is denoted as the moon-to-moon analytical transfer (MMAT) method. It consists of a general methodology for transfer design between the vicinities of the moons in any given system within the context of the circular restricted three-body problem, useful regardless of the orbital planes in which the moons reside. A simplified model enables analytical constraints to efficiently determine the feasibility of a transfer between two different moons moving in the vicinity of a common planet. Subsequently, the strategy builds moon-to-moon transfers based on invariant manifold and transit orbits exploiting some analytical techniques. The strategy is applicable for direct as well as indirect transfers that satisfy the analytical constraints. The transition of the transfers into higher-fidelity ephemeris models confirms the validity of the MMAT method as a fast tool to provide possible transfer options between two consecutive moons. </div><div> </div><div>The current work includes sample applications of transfers between different orbits and planetary systems. The method is efficient and identifies optimal solutions. However, for certain orbital geometries, the direct transfer cannot be constructed because the invariant manifolds do not intersect (due to their mutual inclination, distance, and/or orbital phase). To overcome this difficulty, specific strategies are proposed that introduce intermediate Keplerian arcs and additional impulsive maneuvers to bridge the gaps between trajectories that connect any two moons. The updated techniques are based on the same analytical methods as the original MMAT concept. Therefore, they preserve the optimality of the previous methodology. The basic strategy and the significant additions are demonstrated through a number of applications for transfer scenarios of different types in the Galilean, Uranian, Saturnian and Martian systems. Results are compared with the traditional Lambert arcs. The propellant and time-performance for the transfers are also illustrated and discussed. As far as the exploration of Phobos and Deimos is concerned, a specific design framework that generates transfer trajectories between the Martian moons while leveraging resonant orbits is also introduced. Mars-Deimos resonant orbits that offer repeated flybys of Deimos and arrive at Mars-Phobos libration point orbits are investigated, and a nominal mission scenario with transfer trajectories connecting the two is presented. The MMAT method is used to select the appropriate resonant orbits, and the associated impulsive transfer costs are analyzed. The trajectory concepts are also validated in a higher-fidelity ephemeris model.</div><div> </div><div>Finally, an efficient and general design strategy for transfers between planetary moons that fulfill specific requirements is also included. In particular, the strategy leverages Finite-Time Lyapunov Exponent (FTLE) maps within the context of the MMAT scheme. Incorporating these two techniques enables direct transfers between moons that offer a wide variety of trajectory patterns and endgames designed in the circular restricted three-body problem, such as temporary captures, transits, takeoffs and landings. The technique is applicable to several mission scenarios. Additionally, an efficient strategy that aids in the design of tour missions that involve impulsive transfers between three moons located in their true orbital planes is also included. The result is a computationally efficient technique that allows three-moon tours designed within the context of the circular restricted three-body problem. The method is demonstrated for a Ganymede->Europa->Io tour.</div>