524 research outputs found

    Brave New World versus Island — Utopian and Dystopian Views on Psychopharmacology

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    Aldous Huxley’s Brave New World is a famous dystopia, frequently called upon in public discussions about new biotechnology. It is less well known that 30 years later Huxley also wrote a utopian novel, called Island. This paper will discuss both novels focussing especially on the role of psychopharmacological substances. If we see fiction as a way of imagining what the world could look like, then what can we learn from Huxley’s novels about psychopharmacology and how does that relate to the discussion in the ethical and philosophical literature on this subject? The paper argues that in the current ethical discussion the dystopian vision on psychopharmacology is dominant, but that a comparison between Brave New World and Island shows that a more utopian view is possible as well. This is illustrated by a discussion of the issue of psychopharmacology and authenticity. The second part of the paper draws some further conclusions for the ethical debate on psychopharmacology and human enhancement, by comparing the novels not only with each other, but also with our present reality. It is claimed that the debate should not get stuck in an opposition of dystopian and utopian views, but should address important issues that demand attention in our real world: those of evaluation and governance of enhancing psychopharmacological substances in democratic, pluralistic societies

    Lines, Circles, Planes and Spheres

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    Let SS be a set of nn points in R3\mathbb{R}^3, no three collinear and not all coplanar. If at most nkn-k are coplanar and nn is sufficiently large, the total number of planes determined is at least 1+k(nk2)(k2)(nk2)1 + k \binom{n-k}{2}-\binom{k}{2}(\frac{n-k}{2}). For similar conditions and sufficiently large nn, (inspired by the work of P. D. T. A. Elliott in \cite{Ell67}) we also show that the number of spheres determined by nn points is at least 1+(n13)t3orchard(n1)1+\binom{n-1}{3}-t_3^{orchard}(n-1), and this bound is best possible under its hypothesis. (By t3orchard(n)t_3^{orchard}(n), we are denoting the maximum number of three-point lines attainable by a configuration of nn points, no four collinear, in the plane, i.e., the classic Orchard Problem.) New lower bounds are also given for both lines and circles.Comment: 37 page

    Weak convergence of finite element approximations of linear stochastic evolution equations with additive noise II. Fully discrete schemes

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    We present an abstract framework for analyzing the weak error of fully discrete approximation schemes for linear evolution equations driven by additive Gaussian noise. First, an abstract representation formula is derived for sufficiently smooth test functions. The formula is then applied to the wave equation, where the spatial approximation is done via the standard continuous finite element method and the time discretization via an I-stable rational approximation to the exponential function. It is found that the rate of weak convergence is twice that of strong convergence. Furthermore, in contrast to the parabolic case, higher order schemes in time, such as the Crank-Nicolson scheme, are worthwhile to use if the solution is not very regular. Finally we apply the theory to parabolic equations and detail a weak error estimate for the linearized Cahn-Hilliard-Cook equation as well as comment on the stochastic heat equation

    Auger decay of degenerate and Bose-condensed excitons in Cu2_2O

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    We study the non-radiative Auger decay of excitons in Cu2_2O, in which two excitons scatter to an excited electron and hole. The exciton decay rate for the direct and the phonon-assisted processes is calculated from first principles; incorporating the band structure of the material leads to a relatively shorter lifetime of the triplet state ortho excitons. We compare our results with the Auger decay rate extracted from data on highly degenerate triplet excitons and Bose-condensed singlet excitons in Cu2_2O.Comment: 15 pages, revtex, figures available from G. Kavoulaki

    Surface critical exponents at a uniaxial Lifshitz point

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    Using Monte Carlo techniques, the surface critical behaviour of three-dimensional semi-infinite ANNNI models with different surface orientations with respect to the axis of competing interactions is investigated. Special attention is thereby paid to the surface criticality at the bulk uniaxial Lifshitz point encountered in this model. The presented Monte Carlo results show that the mean-field description of semi-infinite ANNNI models is qualitatively correct. Lifshitz point surface critical exponents at the ordinary transition are found to depend on the surface orientation. At the special transition point, however, no clear dependency of the critical exponents on the surface orientation is revealed. The values of the surface critical exponents presented in this study are the first estimates available beyond mean-field theory.Comment: 10 pages, 7 figures include

    Intercalibration of the barrel electromagnetic calorimeter of the CMS experiment at start-up

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    Calibration of the relative response of the individual channels of the barrel electromagnetic calorimeter of the CMS detector was accomplished, before installation, with cosmic ray muons and test beams. One fourth of the calorimeter was exposed to a beam of high energy electrons and the relative calibration of the channels, the intercalibration, was found to be reproducible to a precision of about 0.3%. Additionally, data were collected with cosmic rays for the entire ECAL barrel during the commissioning phase. By comparing the intercalibration constants obtained with the electron beam data with those from the cosmic ray data, it is demonstrated that the latter provide an intercalibration precision of 1.5% over most of the barrel ECAL. The best intercalibration precision is expected to come from the analysis of events collected in situ during the LHC operation. Using data collected with both electrons and pion beams, several aspects of the intercalibration procedures based on electrons or neutral pions were investigated

    The Future of Psychopharmacological Enhancements: Expectations and Policies

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    The hopes and fears expressed in the debate on human enhancement are not always based on a realistic assessment of the expected possibilities. Discussions about extreme scenarios may at times obscure the ethical and policy issues that are relevant today. This paper aims to contribute to an adequate and ethically sound societal response to actual current developments. After a brief outline of the ethical debate concerning neuro-enhancement, it describes the current state of the art in psychopharmacological science and current uses of psychopharmacological enhancement, as well as the prospects for the near future. It then identifies ethical issues regarding psychopharmacological enhancements that require attention from policymakers, both on the professional and on the governmental level. These concern enhancement research, the gradual expansion of medical categories, off-label prescription and responsibility of doctors, and accessibility of enhancers on the Internet. It is concluded that further discussion on the advantages and drawbacks of enhancers on a collective social level is still needed

    Exploring uncertainties in global crop yield projections in a large ensemble of crop models and CMIP5 and CMIP6 climate scenarios

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    Concerns over climate change are motivated in large part because of their impact on human society. Assessing the effect of that uncertainty on specific potential impacts is demanding, since it requires a systematic survey over both climate and impacts models. We provide a comprehensive evaluation of uncertainty in projected crop yields for maize, spring and winter wheat, rice, and soybean, using a suite of nine crop models and up to 45 CMIP5 and 34 CMIP6 climate projections for three different forcing scenarios. To make this task computationally tractable, we use a new set of statistical crop model emulators. We find that climate and crop models contribute about equally to overall uncertainty. While the ranges of yield uncertainties under CMIP5 and CMIP6 projections are similar, median impact in aggregate total caloric production is typically more negative for the CMIP6 projections (+1% to −19%) than for CMIP5 (+5% to −13%). In the first half of the 21st century and for individual crops is the spread across crop models typically wider than that across climate models, but we find distinct differences between crops: globally, wheat and maize uncertainties are dominated by the crop models, but soybean and rice are more sensitive to the climate projections. Climate models with very similar global mean warming can lead to very different aggregate impacts so that climate model uncertainties remain a significant contributor to agricultural impacts uncertainty. These results show the utility of large-ensemble methods that allow comprehensively evaluating factors affecting crop yields or other impacts under climate change. The crop model ensemble used here is unbalanced and pulls the assumption that all projections are equally plausible into question. Better methods for consistent model testing, also at the level of individual processes, will have to be developed and applied by the crop modeling community

    Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

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    Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe

    Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV

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    A search for a Higgs boson decaying into two photons is described. The analysis is performed using a dataset recorded by the CMS experiment at the LHC from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross section of the standard model Higgs boson decaying to two photons. The expected exclusion limit at 95% confidence level is between 1.4 and 2.4 times the standard model cross section in the mass range between 110 and 150 GeV. The analysis of the data excludes, at 95% confidence level, the standard model Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The largest excess of events above the expected standard model background is observed for a Higgs boson mass hypothesis of 124 GeV with a local significance of 3.1 sigma. The global significance of observing an excess with a local significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is estimated to be 1.8 sigma. More data are required to ascertain the origin of this excess.Comment: Submitted to Physics Letters
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