282 research outputs found
The development and evolution of male androphilia in Samoan fa'afafine
xvii, 201 leaves : ill. ; 29 cmMale androphilia (i.e., male sexual attraction to males) is an evolutionary paradox. It is
unclear how genes for male androphilia persist given that androphilic males have lowered
reproduction? Evidence suggests that ancestral androphilic males were transgendered.
Hence, I address this paradox by focusing on a group of Samoan transgendered
androphilic males (i.e., fa’afafine). Specifically, I show that male androphilia has
consistent developmental correlates across Samoan and Western populations, indicating
that fa’afafine provide a suitable model for the evolution of male androphilia across
populations. In addition, I test hypotheses concerning the evolution of male androphilia.
Fa’afafine’s mothers and grandmothers exhibit elevated reproduction. Also, compared to
Samoan men and women, fa’afafine exhibit unique kin-investment cognition that would
enhance indirect fitness. Elevated reproduction by female kin, and enhanced kin
investments may, therefore, contribute to the evolution of male androphilia. Lastly, I
outline a developmental model for this unique kin-investment cognition in androphilic
males
A Problematic Test of the Kin Selection Hypothesis Among the Urak-Lawoi of Ko Lipe, Thailand: Commentary on Camperio Ciani, Battaglia, and Liotta (2015)
Camperio Ciani et al. argued that the Urak-Lawoi people of Ko Lipe island live in a ‘‘traditional,’’ ‘‘subsistence primitive society’’ reminiscent of the ‘‘ancestral’’ human past and that their socio-cultural situation is ‘‘remarkably similar’’ to Samoa. On this basis, they asserted that the Ko Lipe Urak-Lawoi are an appropriate population for determining the role that kin selection played in the evolution of male androphilia. The purpose of this commentary is to outline some of our concerns with this characterization and with the statistical analyses conducted by Camperio Ciani et al. in their study of the Urak-Lawoi
A Problematic Test of the Kin Selection Hypothesis Among the Urak-Lawoi of Ko Lipe, Thailand: Commentary on Camperio Ciani, Battaglia, and Liotta (2015)
Camperio Ciani et al. argued that the Urak-Lawoi people of Ko Lipe island live in a ‘‘traditional,’’ ‘‘subsistence primitive society’’ reminiscent of the ‘‘ancestral’’ human past and that their socio-cultural situation is ‘‘remarkably similar’’ to Samoa. On this basis, they asserted that the Ko Lipe Urak-Lawoi are an appropriate population for determining the role that kin selection played in the evolution of male androphilia. The purpose of this commentary is to outline some of our concerns with this characterization and with the statistical analyses conducted by Camperio Ciani et al. in their study of the Urak-Lawoi
Protection of stainless-steels against corrosion in sulphidizing environments by Ce oxide coatings: X-ray absorption and thermogravimetric studies
TransCom N2O model inter-comparison - Part 2:Atmospheric inversion estimates of N2O emissions
This study examines N2O emission estimates from five different atmospheric inversion frameworks based on chemistry transport models (CTMs). The five frameworks differ in the choice of CTM, meteorological data, prior uncertainties and inversion method but use the same prior emissions and observation data set. The posterior modelled atmospheric N2O mole fractions are compared to observations to assess the performance of the inversions and to help diagnose problems in the modelled transport. Additionally, the mean emissions for 2006 to 2008 are compared in terms of the spatial distribution and seasonality. Overall, there is a good agreement among the inversions for the mean global total emission, which ranges from 16.1 to 18.7 TgN yr(-1) and is consistent with previous estimates. Ocean emissions represent between 31 and 38% of the global total compared to widely varying previous estimates of 24 to 38%. Emissions from the northern mid- to high latitudes are likely to be more important, with a consistent shift in emissions from the tropics and subtropics to the mid- to high latitudes in the Northern Hemisphere; the emission ratio for 0-30A degrees N to 30-90A degrees N ranges from 1.5 to 1.9 compared with 2.9 to 3.0 in previous estimates. The largest discrepancies across inversions are seen for the regions of South and East Asia and for tropical and South America owing to the poor observational constraint for these areas and to considerable differences in the modelled transport, especially inter-hemispheric exchange rates and tropical convective mixing. Estimates of the seasonal cycle in N2O emissions are also sensitive to errors in modelled stratosphere-to-troposphere transport in the tropics and southern extratropics. Overall, the results show a convergence in the global and regional emissions compared to previous independent studies
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Dose response curve for tumor induction with single and split doses of 10 MeV protons
The response of rat skin to proton irradiation shows a rapid form of recovery of both sublethal and suboncogenic injury and RBE values between 2 and 3. The combination of RBE values greater than one, and recovery indicates that while protons induce injury more efficiently per unit absorbed dose than electrons, there is still a reversible component to the injury process. (auth
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Rat skin carcinogenesis as a basis for estimating risks at low doses and dose rates of various types of radiation
The recovery rate, age dependence and latent period for tumor induction in rat skin were measured for single and split doses of radiation, and the data were analyzed in terms of a general model in an attempt to estimate the expected tumor response for various types of radiation given at low dose rates for long periods of time. The dorsal skin of male rats was exposed to electrons, x rays, or protons in either single or split doses for several doses and the tumor responses were compared during 80 weeks of observation. A two stage model incorporating a reversible or recoverable mode was developed and various parameters in the model, including recovery rate, dose-response coefficients, and indices of age sensitivity, were evaluated experimentally. The measured parameters were then utilized to calculate expected tumor responses for exposure periods extending for duration of life. The calculations indicated that low dose rates could be markedly (/sup 1///sub 100/ to /sup 1///sub 1000/) less effective in producing tumors than the same dose given in a short or acute exposure, although the magnitude of the reduction in effectiveness declines as the dose declines
Elucidating the origins of heterosexual sex differences in mating psychology by examining the behaviour of homosexual men and women
x, 73 leaves ; 28 cm. --Various competing theoretical frameworks have been invoked to explain heterosexual sex differences in mating psychology. Chapter One provides examples of such frameworks, details how considering both heterosexual and homosexual men and women can help identify the most tenable frameworks, and reviews previous research comparing the mating psychology of heterosexual and homosexual men and women. Chapter Two demonstrates the utility of this comparative method by examining the mate retention behaviour of heterosexual and homosexual men and women. Where heterosexual sex differences exist, the mate retention behaviour of homosexual men is largely sex-typical while that of homosexual women is sex-atypical. The significance of these results for explaining heterosexual sex differences in mate retention is discussed. Chapter Three discusses how the data presented and reviewed here might inform our understanding of the psychological mechanisms underlying mating psychology as well as the development of sexual orientation in men and women
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Handling and archiving of magnetic fusion data at DIII-D
Recent modifications to the computer network at DIII-D enhance the collection and distribution of newly acquired and archived experimental data. Linked clients and servers route new data from diagnostic computers to centralized mass storage and distribute data on demand to local and remote workstations and computers. Capacity for data handling exceeds the upper limit of DIII-D Tokamak data production of about 4 GBytes per day. Network users have fast access to new data stored on line. An interactive program handles requests for restoration of data archived off line. Disk management procedures retain selected data on line in preference to other data. Redundancy of all components on the archiving path from the network to magnetic media has prevented loss of data. Older data are rearchived as dictated by limited media life
Offspring Production among the Extended Relatives of Samoan Men and Fa'afafine
Androphilia refers to sexual attraction to adult males, whereas gynephilia refers to sexual attraction to adult females. Male androphilia is an evolutionary paradox. Its development is at least partially influenced by genetic factors, yet male androphiles exhibit lower reproductive output, thus raising the question of how genetic factors underlying its development persist. The sexual antagonism hypothesis posits that the fitness costs associated with genetic factors underlying male androphilia are offset because these same factors lead to elevated reproduction on the part of the female relatives of androphilic males. Western samples drawn from low fertility populations have yielded inconsistent results when testing this hypothesis. Some studies documented elevated reproduction among the matrilineal female kin of androphilic males, whereas others found such effects in the paternal line. Samoa is a high-fertility population in which individuals reproduce closer to their maximum capacities. This study compared the reproductive output of the paternal and maternal line grandmothers, aunts, and uncles of 86 Samoan androphilic males, known locally as fa'afafine, and 86 Samoan gynephilic males. Reproductive output was elevated in the paternal and maternal line grandmothers, but not aunts or uncles, of fa'afafine. These findings are consistent with the sexual antagonism hypothesis and suggest that male androphilia is associated with elevated reproduction among extended relatives in both the maternal and paternal line. Discussion focuses on how this study, in conjunction with the broader literature, informs various models for the evolution of male androphilia via elevated reproduction on the part of female kin
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