1,602 research outputs found

    Are States under a Prospective Duty to Create and Maintain Militaries?

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    Suppose it is foreseeable that you will soon encounter a drowning child, whom you will only be able to rescue if you learn to swim. In this scenario we might think that you have a prospective duty to take swimming lessons given that this will be necessary to perform the future rescue. Cécile Fabre argues that, by parity of reasoning, states have a prospective duty to build and maintain military establishments. My argument in this essay pulls in the opposite direction. First, I emphasize that learning to swim is only a prospective duty under very specific circumstances. Normally there is no such duty; hence, we do not normally think that people deserve moral censure for choosing to forego swimming lessons. I then argue that, similarly, while a prospective duty to build a military can arise under some conceivable circumstances, these are not the circumstances that most states today find themselves in. I then suggest a more fitting domestic analogy to guide our thinking about this issue: Maintaining a standing army is less like learning to swim and more like keeping an assault weapon in the home just in case. This analogy supports a defeasible presumption against militarization

    A view of the implanted SiC damage by Rutherford backscattering spectroscopy, spectroscopic ellipsometry, and transmission electron microscopy

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    4H-SiC single crystalline substrates were implanted at room temperature with 150 keV Al+ ions using fluences of 4 1014, 1 1015, and 2 1015 cm−2 with current density of 2.5 A cm−2. The samples were subsequently annealed at 1100 °C in N2 for 1 h in order to analyze their structural recovery. The disorder induced in both sublattices by the Al+ ions was studied by backscattering spectrometry in channeling geometry with a 3.5 MeV He2+ beam. The results were compared with the optical properties of the samples measured by spectroscopic ellipsometry. In a previous work, we concluded that during the postimplantation annealing of a highly damaged SiC crystalline material the short distance order can be recovered, while the long distance disorder remains. We also presented the possibility to have grains of different polytypes oriented faraway from the original direction. Now, this alternative is confirmed by the cross-sectional transmission and high resolution electron microscopy studies, carried out to obtain information about the crystal structure.Ministerio de Cienncias y Tecnología español-MAT2002-02843 (70% de fondos FEDER)Acuerdo de Colaboración Científica Húngaro-Españo-lE27 / 2001Fondo de Investigaciones Científicas de Hungría (OTKA)-T032029, T047011, T043704 y K6172

    System Advisor Model: Flat Plate Photovoltaic Performance Modeling Validation Report

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    The System Advisor Model (SAM) is a free software tool that performs detailed analysis of both system performance and system financing for a variety of renewable energy technologies. This report provides detailed validation of the SAM flat plate photovoltaic performance model by comparing SAM-modeled PV system generation data to actual measured production data for nine PV systems ranging from 75 kW to greater than 25 MW in size. The results show strong agreement between SAM predictions and field data, with annualized prediction error below 3% for all fixed tilt cases and below 8% for all one axis tracked cases. The analysis concludes that snow cover and system outages are the primary sources of disagreement, and other deviations resulting from seasonal biases in the irradiation models and one axis tracking issues are discussed in detail

    Towards a method for cryopreservation of mosquito vectors of human pathogens

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    Mosquito-borne diseases are responsible for millions of human deaths every year, posing a massive burden on global public health. Mosquitoes transmit a variety of bacteria, parasites and viruses. Mosquito control efforts such as insecticide spraying can reduce mosquito populations, but they must be sustained in order to have long term impacts, can result in the evolution of insecticide resistance, are costly, and can have adverse human and environmental effects. Technological advances have allowed genetic manipulation of mosquitoes, including generation of those that are still susceptible to insecticides, which has greatly increased the number of mosquito strains and lines available to the scientific research community. This generates an associated challenge, because rearing and maintaining unique mosquito lines requires time, money and facilities, and long-term maintenance can lead to adaptation to specific laboratory conditions, resulting in mosquito lines that are distinct from their wild-type counterparts. Additionally, continuous rearing of transgenic lines can lead to loss of genetic markers, genes and/or phenotypes. Cryopreservation of valuable mosquito lines could help circumvent these limitations and allow researchers to reduce the cost of rearing multiple lines simultaneously, maintain low passage number transgenic mosquitoes, and bank lines not currently being used. Additionally, mosquito cryopreservation could allow researchers to access the same mosquito lines, limiting the impact of unique laboratory or field conditions. Successful cryopreservation of mosquitoes would expand the field of mosquito research and could ultimately lead to advances that would reduce the burden of mosquito-borne diseases, possibly through rear-and-release strategies to overcome mosquito insecticide resistance. Cryopreservation techniques have been developed for some insect groups, including but not limited to fruit flies, silkworms and other moth species, and honeybees. Recent advances within the cryopreservation field, along with success with other insects suggest that cryopreservation of mosquitoes may be a feasible method for preserving valuable scientific and public health resources. In this review, we will provide an overview of basic mosquito biology, the current state of and advances within insect cryopreservation, and a proposed approach toward cryopreservation of Anopheles stephensi mosquitoes

    Prototype ATLAS IBL Modules using the FE-I4A Front-End Readout Chip

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    The ATLAS Collaboration will upgrade its semiconductor pixel tracking detector with a new Insertable B-layer (IBL) between the existing pixel detector and the vacuum pipe of the Large Hadron Collider. The extreme operating conditions at this location have necessitated the development of new radiation hard pixel sensor technologies and a new front-end readout chip, called the FE-I4. Planar pixel sensors and 3D pixel sensors have been investigated to equip this new pixel layer, and prototype modules using the FE-I4A have been fabricated and characterized using 120 GeV pions at the CERN SPS and 4 GeV positrons at DESY, before and after module irradiation. Beam test results are presented, including charge collection efficiency, tracking efficiency and charge sharing.Comment: 45 pages, 30 figures, submitted to JINS

    Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

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    The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal

    Search for squarks and gluinos in events with isolated leptons, jets and missing transverse momentum at s√=8 TeV with the ATLAS detector

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    The results of a search for supersymmetry in final states containing at least one isolated lepton (electron or muon), jets and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider are reported. The search is based on proton-proton collision data at a centre-of-mass energy s√=8 TeV collected in 2012, corresponding to an integrated luminosity of 20 fb−1. No significant excess above the Standard Model expectation is observed. Limits are set on supersymmetric particle masses for various supersymmetric models. Depending on the model, the search excludes gluino masses up to 1.32 TeV and squark masses up to 840 GeV. Limits are also set on the parameters of a minimal universal extra dimension model, excluding a compactification radius of 1/R c = 950 GeV for a cut-off scale times radius (ΛR c) of approximately 30

    Hunt for new phenomena using large jet multiplicities and missing transverse momentum with ATLAS in 4.7 fb−1 of s√=7TeV proton-proton collisions

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    Results are presented of a search for new particles decaying to large numbers of jets in association with missing transverse momentum, using 4.7 fb−1 of pp collision data at s√=7TeV collected by the ATLAS experiment at the Large Hadron Collider in 2011. The event selection requires missing transverse momentum, no isolated electrons or muons, and from ≥6 to ≥9 jets. No evidence is found for physics beyond the Standard Model. The results are interpreted in the context of a MSUGRA/CMSSM supersymmetric model, where, for large universal scalar mass m 0, gluino masses smaller than 840 GeV are excluded at the 95% confidence level, extending previously published limits. Within a simplified model containing only a gluino octet and a neutralino, gluino masses smaller than 870 GeV are similarly excluded for neutralino masses below 100 GeV

    Measurement of χ c1 and χ c2 production with s√ = 7 TeV pp collisions at ATLAS

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    The prompt and non-prompt production cross-sections for the χ c1 and χ c2 charmonium states are measured in pp collisions at s√ = 7 TeV with the ATLAS detector at the LHC using 4.5 fb−1 of integrated luminosity. The χ c states are reconstructed through the radiative decay χ c → J/ψγ (with J/ψ → μ + μ −) where photons are reconstructed from γ → e + e − conversions. The production rate of the χ c2 state relative to the χ c1 state is measured for prompt and non-prompt χ c as a function of J/ψ transverse momentum. The prompt χ c cross-sections are combined with existing measurements of prompt J/ψ production to derive the fraction of prompt J/ψ produced in feed-down from χ c decays. The fractions of χ c1 and χ c2 produced in b-hadron decays are also measured
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