4,319 research outputs found

    The Optical Vortex Lens

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    The project seeks to fabricate a vortex lens (phase shift device) using optical lithography with a future goal of using it for astronomy purposes. initially the goal is to create a lens tuned to a HeNe laser (632.8 nm wavelength) with eight photoresist steps, which causes the light to undergo a phase shift. It is this shift that allows the vortex lens to suppress starlight in the vicinity of extra solar planets; it diffracts the light of the star while preserving the image of the nearby planet

    Genome-wide association study of electrocardiographic and heart rate variability traits: the Framingham Heart Study

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    BACKGROUND: Heritable electrocardiographic (ECG) and heart rate variability (HRV) measures, reflecting pacemaking, conduction, repolarization and autonomic function in the heart have been associated with risks for cardiac arrhythmias. Whereas several rare monogenic conditions with extreme phenotypes have been noted, few common genetic factors contributing to interindividual variability in ECG and HRV measures have been identified. We report the results of a community-based genomewide association study of six ECG and HRV intermediate traits. METHODS: Genotyping using Affymetrix 100K GeneChip was conducted on 1345 related Framingham Heart Study Original and Offspring cohort participants. We analyzed 1175 Original and Offspring participants with ECG data (mean age 52 years, 52% women) and 548 Offspring participants with HRV data (mean age 48 years, 51% women), in relation to 70,987 SNPs with minor allele frequency ≥ 0.10, call rate ≥ 80%, Hardy-Weinberg p-value ≥ 0.001. We used generalized estimating equations to test association of SNP alleles with multivariable-adjusted residuals for QT, RR, and PR intervals, the ratio of low frequency to high frequency power (LF/HFP), total power (TP) and the standard deviation of normal RR intervals (SDNN). RESULTS: Associations at p < 10-3 were found for 117 (QT), 105 (RR), 111 (PR), 102 (LF/HF), 121 (TP), and 102 (SDNN) SNPs. Several common variants in NOS1AP (4 SNPs with p-values < 10-3; lowest p-value, rs6683968, p = 1 × 10-4) were associated with adjusted QT residuals, consistent with our previously reported finding for NOS1AP in an unrelated sample of FHS Offspring and other cohorts. All results are publicly available at NCBI's dbGaP at. CONCLUSION: In the community-based Framingham Heart Study none of the ECG and HRV results individually attained genomewide significance. However, the presence of bona fide QT-associated SNPs among the top 117 results for QT duration supports the importance of efforts to validate top results from the reported scans. Finding genetic variants associated with ECG and HRV quantitative traits may identify novel genes and pathways implicated in arrhythmogenesis and allow for improved recognition of individuals at high risk for arrhythmias in the general population.National Institutes of Health (K23 N01-HC25195); Doris Duke Charitable Foundation Clinical Scientist Developement Award; Pfizer; National Institutes of Health National Center for Research Resources Shared Instrumentation grant (1S10RR163736-01A1

    Shareholders’ rights and corporate meetings post COVID‐19

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    Exact 1-D Model for Coherent Synchrotron Radiation with Shielding and Bunch Compression

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    Coherent Synchrotron Radiation has been studied effectively using a 1-dimensional model for the charge distribution in the realm of small angle approximations and high energies. Here we use Jefimenko's form of Maxwell's equations, without such approximations, to calculate the exact wake-fields due to this effect in multiple bends and drifts. It has been shown before that the influence of a drift can propagate well into a subsequent bend. We show, for reasonable parameters, that the influence of a previous bend can also propagate well into a subsequent bend, and that this is especially important at the beginning of a bend. Shielding by conducting parallel plates is simulated using the image charge method. We extend the formalism to situations with compressing and decompressing distributions, and conclude that simpler approximations to bunch compression usually overestimates the effect. Additionally, an exact formula for the coherent power radiated by a Gaussian bunch is derived by considering the coherent synchrotron radiation spectrum, and is used to check the accuracy of wake-field calculations

    Coherent control of population transfer between vibrational states in an optical lattice via two-path quantum interference

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    We demonstrate coherent control of population transfer between vibrational states in an optical lattice by using interference between a one-phonon transition at 2ω2\omega and a two-phonon transition at ω\omega. The ω\omega and 2ω2\omega transitions are driven by phase- and amplitude-modulation of the lattice laser beams, respectively. By varying the relative phase between these two pathways, we control the branching ratio of transitions to the first excited state and to the higher states. Our best result shows an improvement of the branching ratio by a factor of 3.5±\pm0.7. Such quantum control techniques may find broad application in suppressing leakage errors in a variety of quantum information architectures.Comment: 5 pages, 4 figure

    Time is Money: An Empirical Assessment of Non-Economic Damages Arguments

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    Non-economic damages (pain and suffering) are the most significant and variable components of liability. Our survey of fifty-one U.S. jurisdictions shows wide heterogeneity in whether attorneys may quantify damages as time-units of suffering (per diem) or demand a specific amount (lump sum). Either sort of large number could exploit an irrational anchoring effect. We performed a realistic, online, video-based experiment with 732 human subjects. We replicated prior work showing that large lump sum demands drive larger jury verdicts, but surprisingly found no effect of similarly-sized per diem anchors. We did find per diem effects on binary liability outcomes, and thus expected case values, and we discuss potential causal mechanisms, based in the cognitive science literature. This empirical work contradicts the speculations by scholars and courts that per diem arguments powerfully impact damage awards by exploiting juror irrationality. Nonetheless, our data surprisingly shows per diem arguments enhancing the expected value of cases by increasing win rates, perhaps because they allow plaintiffs to explain the basis for a large request. This latter dynamic would not seem to justify the proscription currently employed in some jurisdictions

    The New Settlement Tools

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    By protecting the right to a jury, the state and federal constitutions recognize the fundamental value of having civil and criminal disputes resolved by laypersons. Actual trials, however, are relatively rare, in part because parties seek to avoid the risks and cost of trials and courts seek to clear dockets efficiently. But as desirable as settlement may be, it can be a difficult way to resolve a dispute. Parties view their cases from different perspectives, and these perspectives often cause both sides to be overly optimistic and to expect unreasonably large or unreasonably small resolutions. This article describes a novel method of incorporating layperson perspectives to provide parties with more accurate information about the value of a case: We suggest that parties work with mediators or settlement judges to create mini-trials and recruit hundreds of online mock jurors to render decisions. By applying modern statistical techniques to these results, the mediators could show the parties the likelihood of possible outcomes and collect qualitative information about strengths and weaknesses for each side. These data will better inform the parties’ views and should thereby facilitate settlement

    Ebola virus VP30 and nucleoprotein interactions modulate viral RNA synthesis

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    AbstractEbola virus (EBOV) is an enveloped negative-sense RNA virus that causes sporadic outbreaks with high case fatality rates. Ebola viral protein 30 (eVP30) plays a critical role in EBOV transcription initiation at the nucleoprotein (eNP) gene, with additional roles in the replication cycle such as viral assembly. However, the mechanistic basis for how eVP30 functions during the virus replication cycle is currently unclear. Here we define a key interaction between eVP30 and a peptide derived from eNP that is important to facilitate interactions leading to the recognition of the RNA template. We present crystal structures of the eVP30 C-terminus in complex with this eNP peptide. Functional analyses of the eVP30–eNP interface identify residues that are critical for viral RNA synthesis. Altogether, these results support a model where the eVP30–eNP interaction plays a critical role in transcription initiation and provides a novel target for the development of antiviral therapy.</jats:p

    Cryptococcal choroiditis in advanced AIDS with clinicopathologic correlation.

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    PurposeTo describe a case of disseminated cryptococcal meningitis with multifocal choroiditis and provide optical coherence tomography (OCT) findings correlated with described histopathology in a patient with advanced acquired immunodeficiency syndrome (AIDS).ObservationsThe patient was a 54-year-old man with AIDS who presented with dyspnea and headache followed by acute vision loss. OCT demonstrated a lesion with a small area of fluid that was limited by a more prominent and irregular external limiting membrane with underlying nodular choroidal thickening, mild RPE disorganization, and hyperreflectivity of the overlying photoreceptor layer. Patient was found to have disseminated cryptococcal infection and passed away despite aggressive therapy. Autopsy was performed including bilateral enucleation and a Cryptococcus lesion was confirmed on histopathology.Conclusion and importanceThis case highlights the clinical, imaging, and histopathologic findings of cryptococcal choroiditis and provides a review of the updated treatment recommendations for disseminated infection in a patient with advanced AIDS. Although currently fundoscopy has proven most useful in directing the diagnostic algorithm in choroiditis in the setting of advanced immunosuppression, OCT may provide insight into the spread of Cryptococcus within the eye
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