1,707 research outputs found
Deliberative Constitutionalism in the National Security Setting
Deliberative democracy theory maintains that authentic deliberation about matters of public concern is an essential condition for the legitimacy of political decisions. Such deliberation has two features. The first is deliberative rigor. This is deliberation guided by public-regarding reasons in a process in which persons are genuinely open to the force of the better argument. The second is transparency. This requires that requires that officials publicly explain the reasons for their decisions in terms that citizens can endorse as acceptable grounds for acting in the name of the political community.
Such requirements would seem to be especially important in the national security setting, where decisions can have profound life-and-death consequences. Yet this is the setting in which transparency often is least feasible on the part of the Executive branch. Officials may be constrained for good reasons from fully explaining the bases for their decisions. While such reason-giving is especially important to the perceived legitimacy of a decision, anticipating the need to provide it also can enhance deliberative rigor. Limited transparency thus creates the risk both that crucial decisions may not be regarded as legitimate, and that the deliberative process will not be as robust as it should be.
In this chapter, we argue that ensuring robust internal deliberative processes in the national security setting can compensate at least to some degree for this limitation. Appreciating the demands of deliberative democracy theory can help inform this process by illuminating how various procedural mechanisms may promote the goals that transparency purports to serve. We focus on the Lawyers Group, which includes senior national security lawyers from across the government, as an example of an arrangement that can help further the ends of deliberative democracy by providing a vehicle for deliberation that meets many, even if not all, of the requirements of that theory. Coordinated by the legal advisor for the National Security Council, this group discusses national security issues that will be presented to the President.
We regard our analysis as contributing in two ways to deliberative democratic theory. First, it focuses on the possibility of satisfying the requirement of this theory in a setting in which decision-making often falls short of the demands of full transparency. Second, it suggests how legal analysis may play a distinctive role in the deliberative process.
There are limits to what the Lawyers Group can accomplish. We believe, however, that it should be assessed in terms of its contribution to the larger national security deliberative system of which it is a part. From this perspective, the Group’s compliance with several prescriptions of deliberative theory helps it strengthen, even if it does not guarantee, the rigor and persuasiveness of the justifications that the President is able to provide for national security decisions
Electrically monitoring DNA repair by photolyase
Cyclobutane pyrimidine dimers are the major DNA photoproducts produced upon exposure to UV radiation. If left unrepaired, these lesions can lead to replication errors, mutation, and cell death. Photolyase is a light-activated flavoenzyme that binds to pyrimidine dimers in DNA and repairs them in a reaction triggered by electron transfer from the photoexcited flavin cofactor to the dimer. Using gold electrodes modified with DNA duplexes containing a cyclobutane thymine dimer (T T), here we probe the electrochemistry of the flavin cofactor in Escherichia coli photolyase. Cyclic and square-wave voltammograms of photolyase deposited on these electrodes show a redox signal at 40 mV versus normal hydrogen electrode, consistent with electron transfer to and from the flavin in the DNA-bound protein. This signal is dramatically attenuated on surfaces where the pi-stacking of the DNA bases is perturbed by the presence of an abasic site below the T T, an indication that the redox pathway is DNA-mediated. DNA repair can, moreover, be monitored electrically. Exposure of photolyase on T T-damaged DNA films to near-UV/blue light leads to changes in the flavin signal consistent with repair, as confirmed by parallel HPLC experiments. These results demonstrate the exquisite sensitivity of DNA electrochemistry to perturbations in base pair stacking and the applicability of this chemistry to probe reactions of proteins with DNA
Using Coronal Loops to Reconstruct the Magnetic Field of an Active Region Before and After a Major Flare
The shapes of solar coronal loops are sensitive to the presence of electrical
currents that are the carriers of the nonpotential energy available for
impulsive activity. We use this information in a new method for modeling the
coronal magnetic field of AR 11158 as a nonlinear force-free field (NLFFF). The
observations used are coronal images around time of major flare activity on
2011/02/15, together with the surface line-of-sight magnetic field
measurements. The data are from the Helioseismic and Magnetic Imager and
Atmospheric Imaging Assembly (HMI and AIA, respectively) onboard the Solar
Dynamics Observatory (SDO). The model fields are constrained to approximate the
coronal loop configurations as closely as possible, while also subject to the
force-free constraints. The method does not use transverse photospheric
magnetic field components as input, and is thereby distinct from methods for
modeling NLFFFs based on photospheric vector magnetograms. We validate the
method using observations of AR 11158 at a time well before major flaring, and
subsequently review the field evolution just prior to and following an X2.2
flare and associated eruption. The models indicate that the energy released
during the instability is about erg, consistent with what is
needed to power such a large eruptive flare. Immediately prior to the eruption
the model field contains a compact sigmoid bundle of twisted flux that is not
present in the post-eruption models, which is consistent with the observations.
The core of that model structure is twisted by full turns about
its axis.Comment: ApJ, in pres
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KE basin recirculation/skimmer/IX systems restart acceptance test report
The 105 KE Basin Recirculation System and Skimmer Loop have been upgraded to provide the flexibility to run the Ion Exchange Modules on either system to support spent fuel removal for the Spent Nuclear Fuel Project. This Acceptance Test Report Provides the documentation of the leak Testing for the construction work associated with the IXM inlet and outlet piping, places the cartridge filters back in service and provides the functional testing of the IXM`s on the recirculation and skimmer systems
Oscar Wilde\u27s Fiction: Views on Life and Art
Oscar Wilde depicts different views on life and art. The stories selected have common themes of wealth (monetary/non-monatary), love, devotion, self-destruction and death:: The Picture of Dorian Gray, The Happy Prince, The Devoted Friend, The Selfish Giant, and The Rose and the Nightingale. These four fairy tales tie in nicely with Wilde\u27s novel to show the true value of life and art
A Method for Data-Driven Simulations of Evolving Solar Active Regions
We present a method for performing data-driven simulations of solar active
region formation and evolution. The approach is based on magnetofriction, which
evolves the induction equation assuming the plasma velocity is proportional to
the Lorentz force. The simulations of active region coronal field are driven by
temporal sequences of photospheric magnetograms from the Helioseismic Magnetic
Imager (HMI) instrument onboard the Solar Dynamics Observatory (SDO). Under
certain conditions, the data-driven simulations produce flux ropes that are
ejected from the modeled active region due to loss of equilibrium. Following
the ejection of flux ropes, we find an enhancement of the photospheric
horizontal field near the polarity inversion line. We also present a method for
the synthesis of mock coronal images based on a proxy emissivity calculated
from the current density distribution in the model. This method yields mock
coronal images that are somewhat reminiscent of images of active regions taken
by instruments such as SDO's Atmospheric Imaging Assembly (AIA) at extreme
ultraviolet wavelengths.Comment: Accepted to ApJ; comments/questions related to this article are
welcome via e-mail, even after publicatio
Selection and Characterization of a Novel DNA Aptamer for Label-Free Fluorescence Biosensing of Ochratoxin A
Nucleic acid aptamers are emerging as useful molecular recognition tools for food safety monitoring. However, practical and technical challenges limit the number and diversity of available aptamer probes that can be incorporated into novel sensing schemes. This work describes the selection of novel DNA aptamers that bind to the important food contaminant ochratoxin A (OTA). Following 15 rounds of in vitro selection, sequences were analyzed for OTA binding. Two of the isolated aptamers demonstrated high affinity binding and selectivity to this mycotoxin compared to similar food adulterants. These sequences, as well as a truncated aptamer (minimal sequence required for binding), were incorporated into a SYBR® Green I fluorescence-based OTA biosensing scheme. This label-free detection platform is capable of rapid, selective, and sensitive OTA quantification with a limit of detection of 9 nM and linear quantification up to 100 nM
Euclid Space Mission: building the sky survey
The Euclid space mission proposes to survey 15000 square degrees of the
extragalactic sky during 6 years, with a step-and-stare technique. The
scheduling of observation sequences is driven by the primary scientific
objectives, spacecraft constraints, calibration requirements and physical
properties of the sky. We present the current reference implementation of the
Euclid survey and on-going work on survey optimization.Comment: to appear in Proceedings IAU Symposium No. 306, "Statistical
Challenges in 21st Century Cosmology", A.F. Heavens, J.-L. Starck & A.
Krone-Martins, ed
Challenges and Opportunities for Small Molecule Aptamer Development
Aptamers are single-stranded oligonucleotides that bind to targets with high affinity and selectivity. Their use as molecular recognition elements has emerged as a viable approach for biosensing, diagnostics, and therapeutics. Despite this potential, relatively few aptamers exist that bind to small molecules. Small molecules are important targets for investigation due to their diverse biological functions as well as their clinical and commercial uses. Novel, effective molecular recognition probes for these compounds are therefore of great interest. This paper will highlight the technical challenges of aptamer development for small molecule targets, as well as the opportunities that exist for their application in biosensing and chemical biology
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