842 research outputs found
A Fundamental Problem: The Vulnerability of Intellectual Property Licenses in Chapter 15 and the Meaning of § 1506
While the United States has been able to protect the growth of intellectual property within its own borders, especially in the context of the Code, the increasingly global economy has left these protections ineffective in international insolvency cases. Current law leaves intellectual property licenses vulnerable to foreign laws that allow debtors to unilaterally and completely cancel the license, contrary to United States law. This severely threatens the continuing growth of intellectual property in the United States. This Comment suggests that § 1506 allows courts to deny comity where needed to protect intellectual property licenses. Doing so will ensure the security of such licenses in a chapter 15 case, thereby promoting a robust licensing market and ultimately encouraging continued investment in the development of intellectual property in the United States
Modeling High Quantum Bit Rate QKD Systems over Optical Fiber
There is considerable interest in finding conditions under which the quantum
key distribution (QKD) propagation distances over fiber and secure key rate
(SKR) are maximized for a given acceptable quantum bit error rate. One way to
increase the secure key rate is to increase quantum bit rate, i.e. use shorter
pulses. Short pulses propagating in a fiber are subject to temporal broadening
caused by chromatic dispersion (CD) which leads to inter-symbol-interference
and quantum bit-error rate increase. Current commercial QKD systems employ 1
Gb/s quantum bit rate sources, and the transition to 10 Gb/s system is being
researched. While not very important in the 1 Gb/s, the effect of CD cannot be
neglected in 10 Gb/s or higher quantum bit rate systems.Comment: 10 pages, 4 figures, submitted to EPE18 SPIE Photonics Europ
Mode division multiplexing using an orbital angular momentum mode sorter and MIMO-DSP over a graded-index few-mode optical fibre
Mode division multiplexing (MDM)– using a multimode optical fiber’s N spatial modes as data channels to transmit N independent data streams – has received interest as it can potentially increase optical fiber data transmission capacity N-times with respect to single mode optical fibers. Two challenges of MDM are (1) designing mode (de)multiplexers with high mode selectivity (2) designing mode (de)multiplexers without cascaded beam splitting’s 1/N insertion loss. One spatial mode basis that has received interest is that of orbital angular momentum (OAM) modes. In this paper, using a device referred to as an OAM mode sorter, we show that OAM modes can be (de)multiplexed over a multimode optical fiber with higher than −15 dB mode selectivity and without cascaded beam splitting’s 1/N insertion loss. As a proof of concept, the OAM modes of the LP11 mode group (OAM−1,0 and OAM+1,0), each carrying 20-Gbit/s polarization division multiplexed and quadrature phase shift keyed data streams, are transmitted 5km over a graded-index, few-mode optical fibre. Channel crosstalk is mitigated using 4 × 4 multiple-input-multiple-output digital-signal-processing with <1.5 dB power penalties at a bit-error-rate of 2 × 10−3
Quantum Walks in Quasi-Periodic Photonics Lattices
We present construction rules for a new class of quasiperiodic photonics lattices (QPL) to realize localized quantum walks (LQWs) deterministically. The new quasiperiodic structures are constructed symmetrically with Fibonacci, Thue-Morse, and other quasiperiodic sequences. Our construction rules allow us to build the symmetrical quasiperiodic photonics lattices. As a result, LQWs with symmetrical probability distributions can be realized in these QPLs. Furthermore, the proposed QPLs are composed with different waveguides providing both on- and off-diagonal deterministic disorders. We show LQWs in the proposed QPLs are highly programmable and controllable
A CNO Dichotomy among O2 Giant Spectra in the Magellanic Clouds
From a survey of the 3400 Ã… region in the earliest O-type spectra, we have found that two of the four O2 giants observed in the Large Magellanic Cloud have O IV lines there that are stronger than the N IV lines, while the other two have the opposite. A Small Magellanic Cloud counterpart also has N IV stronger than O IV. Inspection of the blue spectra of these stars shows that the former pair have weaker N lines in all ionization states (III, IV, and V) present as well as lines of C IV λ4658, while the latter three have stronger N lines and greater He/H. Space ultraviolet observations of two of the N-strong stars show N V wind profiles substantially stronger than those of C IV, while in the N-weak stars the C IV features are equal to or stronger than the N V. The N-strong stars are now reclassified as ON2 III(f*), newly defining that category. These characteristics strongly suggest a larger fraction of processed material in the atmospheres of the ON2 stars, which we confirm by modeling the optical spectra. In the context of current models, it is in turn implied that the ON2 stars are in a more advanced evolutionary state than the others, and/or that they had higher initial rotational velocities. The recent formulation of the effects of rotation on massive stellar evolution introduces an additional fundamental parameter, which the CNO abundances are in principle able to constrain. We present some illustrative comparisons with current Geneva evolutionary models for rotating massive stars. It is possible that these very hot, nitrogen-rich objects are products of homogeneous evolution. Our results will provide motivation for further physical modeling of the atmospheres and evolutionary histories of the most massive hot stars.Fil: Walborn, Nolan Revere. Space Telescope Science Institute; Estados UnidosFil: Morrell, Nidia Irene. Las campanas observatory; ChileFil: Howarth, Ian D.. University College London; Estados UnidosFil: Crowther, Paul A.. University of Sheffield; Reino UnidoFil: Lennon, Daniel J.. Isaac Newton Group of Telescopes; EspañaFil: Massey, Philip. Lowell Observatory; Estados UnidosFil: Arias, Julia Ines. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y GeofÃsicas; Argentin
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Neurological, Cognitive, and Psychological Findings Among Survivors of Ebola Virus Disease From the 1995 Ebola Outbreak in Kikwit, Democratic Republic of Congo: A Cross-sectional Study.
BackgroundClinical sequelae of Ebola virus disease (EVD) have not been described more than 3 years postoutbreak. We examined survivors and close contacts from the 1995 Ebola outbreak in Kikwit, Democratic Republic of Congo (DRC), and determined prevalence of abnormal neurological, cognitive, and psychological findings and their association with EVD survivorship.MethodsFrom August to September 2017, we conducted a cross-sectional study in Kikwit, DRC. Over 2 decades after the EVD outbreak, we recruited EVD survivors and close contacts from the outbreak to undergo physical examination and culturally adapted versions of the Folstein mini-mental status exam (MMSE) and Goldberg anxiety and depression scale (GADS). We estimated the strength of relationships between EVD survivorship and health outcomes using linear regression models by comparing survivors versus close contacts, adjusting for age, sex, educational level, marital status, and healthcare worker status.ResultsWe enrolled 20 EVD survivors and 187 close contacts. Among the 20 EVD survivors, 4 (20%) reported at least 1 abnormal neurological symptom, and 3 (15%) had an abnormal neurological examination. Among the 187 close contacts, 14 (11%) reported at least 1 abnormal neurologic symptom, and 9 (5%) had an abnormal neurological examination. EVD survivors had lower mean MMSE and higher mean GADS scores as compared to close contacts (MMSE: adjusted coefficient: -1.85; 95% confidence interval [CI]: -3.63, -0.07; GADS: adjusted coefficient: 3.91; 95% CI: 1.76, 6.04).ConclusionsEVD survivors can have lower cognitive scores and more symptoms of depression and anxiety than close contacts more than 2 decades after Ebola virus outbreaks
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