2,661 research outputs found

    The effect of exposure to radiofrequency fields on cancer risk in the general and working population: a protocol for a systematic review of human observational studies

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    BACKGROUND: The World Health Organization (WHO) has an ongoing project to assess potential health effects of exposure to radiofrequency electromagnetic fields (RF-EMF) in the general and working population. Here we present the protocol for a systematic review of the scientific literature on cancer hazards from exposure to RF-EMF in humans, commissioned by the WHO as part of that project. OBJECTIVE: To assess the quality and strength of the evidence provided by human observational studies for a causal association between exposure to RF-EMF and risk of neoplastic diseases. ELIGIBILITY CRITERIA: We will include cohort and case-control studies investigating neoplasia risks in relation to three types of exposure to RF-EMF: near-field, head-localized, exposure from wireless phone use (SR-A); far-field, whole body, environmental exposure from fixed-site transmitters (SR-B); near/far-field occupational exposures from use of handheld transceivers or RF-emitting equipment in the workplace (SR-C). While no restriction on tumour type will be applied, we will focus on selected neoplasms of the central nervous system (brain, meninges, pituitary gland, acoustic nerve) and salivary gland tumours (SR-A); brain tumours and leukaemias (SR-B, SR-C). INFORMATION SOURCES: Eligible studies will be identified through Medline, Embase, and EMF-Portal. RISK-OF-BIAS ASSESSMENT: We will use a tailored version of the OHAT's tool to evaluate the study's internal validity. DATA SYNTHESIS: We will consider separately studies on different tumours, neoplasm-specific risks from different exposure sources, and a given exposure-outcome pair in adults and children. When a quantitative synthesis of findings can be envisaged, the main aims of the meta-analysis will be to assess the strength of association and the shape of the exposure-response relationship; to quantify the degree of heterogeneity across studies; and explore the sources of inconsistency (if any). When a meta-analysis is judged inappropriate, we will perform a narrative synthesis, complemented by a structured tabulation of results and appropriate visual displays. EVIDENCE ASSESSMENT: Confidence in evidence will be assessed in line with the GRADE approach. FUNDING: This project is supported by the World Health Organization. Co-financing was provided by the New Zealand Ministry of Health; the Istituto Superiore di Sanita in its capacity as a WHO Collaborating Centre for Radiation and Health; ARPANSA as a WHO Collaborating Centre for Radiation Protection. REGISTRATION: PROSPERO CRD42021236798

    Aspirin for the older person: report of a meeting at the Royal Society of Medicine, London, 3rd November 2011

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    On November 23rd 2011, the Aspirin Foundation held a meeting at the Royal Society of Medicine in London to review current thinking on the potential role of aspirin in preventing cardiovascular disease and reducing the risk of cancer in older people. The meeting was supported by Bayer Pharma AG and Novacyl

    Neutrino Parameters, Abelian Flavor Symmetries, and Charged Lepton Flavor Violation

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    Neutrino masses and mixings have important implications for models of fermion masses, and, most directly, for the charged lepton sector. We consider supersymmetric Abelian flavor models, where neutrino mass parameters are related to those of charged leptons and sleptons. We show that processes such as \tau to \mu\gamma, \mu to e\gamma and \mu-e conversion provide interesting probes. In particular, some existing models are excluded by current bounds, while many others predict rates within reach of proposed near future experiments. We also construct models in which the predicted rates for charged lepton flavor violation are below even the proposed experimental sensitivities, but argue that such models necessarily involve loss of predictive power.Comment: 27 pages, refs added, published versio

    Observation of CP Violation in K(L)->pi+pi-e+e- Decays

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    We report the first observation of a manifestly CP violating effect in the K(L)->pi+pi-e+e- decay mode. A large asymmetry was observed in the distribution of these decays in the CP-odd and T-odd angle phi between the decay planes of the e+e- and pi+pi- pairs in the K(L) center of mass system. After acceptance corrections, the overall asymmetry is found to be 13.6+-2.5 (stat) +-1.2 (syst)%. This is the largest CP-violating effect yet observed integrating over the entire phase space of a mode and the first such effect observed in an angular variable.Comment: 4 pages 4 figures submitted to pr

    Neutrino masses and mixings in a seesaw framework

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    Assuming the seesaw mechanism for hierarchical neutrino masses, we calculate the heavy neutrino masses under the hypotheses that the mixing in the Dirac leptonic sector is similar to the quark mixing (VDVCKMV_D \sim V_{CKM}) and that MνMuM_{\nu} \sim M_u or MeM_e, where MνM_{\nu} is the Dirac mass matrix of neutrinos. As a result we find that for MνMuM_{\nu} \sim M_u the vacuum oscillation solution of the solar neutrino problem leads to a scale for the heavy neutrino mass well above the unification scale, while for the MSW solutions there is agreement with this scale. For MνMeM_{\nu} \sim M_e the vacuum solution is consistent with the unification scale, and the MSW solutions with an intermediate scale. The mass of the lightest heavy neutrino can be as small as 10510^5 GeV.Comment: 13 pages RevTex, no figures. Revised versio

    Neutrino Masses and Lepton-Flavor Violation in Supersymmetric Models with lopsided Froggatt-Nielsen charges

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    We analyze in detail lepton-flavor violation (LFV) in the charged-lepton sector such as μeγ\mu \to e \gamma, τμγ\tau \to \mu \gamma, μeee\mu \to eee and the μe\mu \to e conversion in nuclei, within the framework of supersymmetric models with lopsided Froggatt--Nielsen charges, in which the large mixing in the neutrino sector as well as small mixings in the quark sector can be naturally accommodated. We show that the present experimental limits on the LFV processes already exclude some of the models. The future proposed search for LFV, especially in muon processes, can provide a significant probe to this framework. We also stress the importance of the measurement of Ue3MNSU^{MNS}_{e3} in neutrino experiments, and the fact that the KamLAND experiment could play a significant role to test a certain class of models.Comment: 33 pages, 20 figure

    A Calculable Toy Model of the Landscape

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    Motivated by recent discussions of the string-theory landscape, we propose field-theoretic realizations of models with large numbers of vacua. These models contain multiple U(1) gauge groups, and can be interpreted as deconstructed versions of higher-dimensional gauge theory models with fluxes in the compact space. We find that the vacuum structure of these models is very rich, defined by parameter-space regions with different classes of stable vacua separated by boundaries. This allows us to explicitly calculate physical quantities such as the supersymmetry-breaking scale, the presence or absence of R-symmetries, and probabilities of stable versus unstable vacua. Furthermore, we find that this landscape picture evolves with energy, allowing vacua to undergo phase transitions as they cross the boundaries between different regions in the landscape. We also demonstrate that supergravity effects are crucial in order to stabilize most of these vacua, and in order to allow the possibility of cancelling the cosmological constant.Comment: 49 pages, LaTeX, 13 figures, references adde

    Don't Stop Thinking About Leptoquarks: Constructing New Models

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    We discuss the general framework for the construction of new models containing a single, fermion number zero scalar leptoquark of mass 200220\simeq 200-220 GeV which can both satisfy the D0/CDF search constraints as well as low energy data, and can lead to both neutral and charged current-like final states at HERA. The class of models of this kind necessarily contain new vector-like fermions with masses at the TeV scale which mix with those of the Standard Model after symmetry breaking. In this paper we classify all models of this type and examine their phenomenological implications as well as their potential embedding into SUSY and non-SUSY GUT scenarios. The general coupling parameter space allowed by low energy as well as collider data for these models is described and requires no fine-tuning of the parameters.Comment: Modified text, added table, and updated reference
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