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The Federal Cybersecurity Workforce: Background and Congressional Oversight Issues for the Departments of Defense and Homeland Security
[Excerpt] This report examines congressional oversight of two strategies undertaken by Congress and the executive branch to strengthen the federal cybersecurity workforce: (1) initiatives to define and identify the federal cybersecurity workforce, and (2) hiring and pay flexibilities applicable to cybersecurity positions at DOD and DHS. This report focuses on DOD and DHS because of their key roles in federal cybersecurity and because the majority of hiring and pay flexibilities for cybersecurity professionals authorized by Congress apply to DOD and DHS
Numerical precision radiative corrections to the Dalitz plot of baryon semileptonic decays including the spin-momentum correlation of the decaying and emitted baryons
We calculate the radiative corrections to the angular correlation between the
polarization of the decaying and the direction of the emitted spin one-half
baryons in the semileptonic decay mode. The final results are presented, first,
with the triple integration of the bremsstrahlung photon ready to be performed
numerically and, second, in an analytical form. A third presentation of our
results in the form of numerical arrays of coefficients to be multiplied by the
quadratic products of form factors is discussed. This latter may be the most
practical one to use in Monte Carlo simulations. A series of crosschecks is
performed. Previous results to order (alpha/pi)(q/M_1) for the decays of
unpolarized baryons are reviewed, too, where q is the momentum transfer and M_1
is the mass of the decaying baryon. This paper is self-contained and organized
to make it accessible and reliable in the analysis of the Dalitz plot of
precision experiments involving heavy quarks and is not compromised to fixing
the form factors at predetermined values. It is assumed that the real photons
are kinematically discriminated. Otherwise, our results have a general
model-independent applicability.Comment: 34 pages, 4 tables, no figures. Some sections have been shortened.
Conclusions remain unchange
Generalizing Boolean Satisfiability I: Background and Survey of Existing Work
This is the first of three planned papers describing ZAP, a satisfiability
engine that substantially generalizes existing tools while retaining the
performance characteristics of modern high-performance solvers. The fundamental
idea underlying ZAP is that many problems passed to such engines contain rich
internal structure that is obscured by the Boolean representation used; our
goal is to define a representation in which this structure is apparent and can
easily be exploited to improve computational performance. This paper is a
survey of the work underlying ZAP, and discusses previous attempts to improve
the performance of the Davis-Putnam-Logemann-Loveland algorithm by exploiting
the structure of the problem being solved. We examine existing ideas including
extensions of the Boolean language to allow cardinality constraints,
pseudo-Boolean representations, symmetry, and a limited form of quantification.
While this paper is intended as a survey, our research results are contained in
the two subsequent articles, with the theoretical structure of ZAP described in
the second paper in this series, and ZAP's implementation described in the
third
Radiative Corrections to the Decay Revised
We consider the lowest order radiative corrections for the decay , usually referred as decay. This decay is the
best way to extract the value of the element of the CKM matrix. The
radiative corrections become crucial if one wants a precise value of .
The existing calculations were performed in the late 60's \cite{B,G} and are in
disagreement. The calculation in \cite{G} turns out to be ultraviolet cutoff
sensitive. The necessity of precise knowledge of and the contradiction
between the existing results constitute the motivation of our paper.
We remove the ultraviolet cutoff dependence by using A.Sirlin's prescription;
we set it equal to the mass. We establish the whole character of small
lepton mass dependence based on the renormalization group approach. In this way
we can provide a simple explanation of Kinoshita--Lee--Nauenberg cancellation
of singularities in the lepton mass terms in the total width and pion spectrum.
We give an explicit evaluation of the structure--dependent photon emission
based on ChPT in the lowest order. We estimate the accuracy of our results to
be at the level of 1%. The corrected total width is
with . Using the formfactor value calculated in \cite{CKNRT} leads to .Comment: 29 pages, 4 figures, 2 tables, uses feynmf.st
Data management study, volume 5. Appendix J - Contractor data package procurement and contracting /PC/ Final report
Contractor data package for administration of procurement and contracting of Voyager spacecraft system
Generalizing Boolean Satisfiability II: Theory
This is the second of three planned papers describing ZAP, a satisfiability
engine that substantially generalizes existing tools while retaining the
performance characteristics of modern high performance solvers. The fundamental
idea underlying ZAP is that many problems passed to such engines contain rich
internal structure that is obscured by the Boolean representation used; our
goal is to define a representation in which this structure is apparent and can
easily be exploited to improve computational performance. This paper presents
the theoretical basis for the ideas underlying ZAP, arguing that existing ideas
in this area exploit a single, recurring structure in that multiple database
axioms can be obtained by operating on a single axiom using a subgroup of the
group of permutations on the literals in the problem. We argue that the group
structure precisely captures the general structure at which earlier approaches
hinted, and give numerous examples of its use. We go on to extend the
Davis-Putnam-Logemann-Loveland inference procedure to this broader setting, and
show that earlier computational improvements are either subsumed or left intact
by the new method. The third paper in this series discusses ZAPs implementation
and presents experimental performance results
Generalizing Boolean Satisfiability III: Implementation
This is the third of three papers describing ZAP, a satisfiability engine
that substantially generalizes existing tools while retaining the performance
characteristics of modern high-performance solvers. The fundamental idea
underlying ZAP is that many problems passed to such engines contain rich
internal structure that is obscured by the Boolean representation used; our
goal has been to define a representation in which this structure is apparent
and can be exploited to improve computational performance. The first paper
surveyed existing work that (knowingly or not) exploited problem structure to
improve the performance of satisfiability engines, and the second paper showed
that this structure could be understood in terms of groups of permutations
acting on individual clauses in any particular Boolean theory. We conclude the
series by discussing the techniques needed to implement our ideas, and by
reporting on their performance on a variety of problem instances
Downsizing Democracy
Originally publushed in 2002. In Downsizing Democracy, Matthew A. Crenson and Benjamin Ginsberg describe how the once powerful idea of a collective citizenry has given way to a concept of personal, autonomous democracy. Today, political change is effected through litigation, lobbying, and term limits, rather than active participation in the political process, resulting in narrow special interest groups dominating state and federal decision-making. At a time when an American's investment in the democratic process has largely been reduced to an annual contribution to a political party or organization, Downsizing Democracy offers a critical reassessment of American democracy
Brief of Amici Curiae Andrea Armstrong, Sharon Dolovich, Betsy Ginsberg, Michael B. Mushlin, Alexander A. Reinert, Laura Rovner, and Margo Schlanger in Support of Plaintiff-Appellee
Amici are legal scholars who study the treatment of incarcerated people under the Eighth Amendment to the United States Constitution. Writing and teaching about this topic is a central focus of their work. Amici have a shared interest in the lawful treatment of incarcerated men and women and fidelity to the principles established by the Supreme Court of the United States in Estelle v. Gamble, 429 U.S. 97 (1976). They believe that all people, regardless of their gender identity, are entitled to constitutionally adequate medical treatment consistent with the rule of Estelle
Recreation of the terminal events in physiological integrin activation.
Increased affinity of integrins for the extracellular matrix (activation) regulates cell adhesion and migration, extracellular matrix assembly, and mechanotransduction. Major uncertainties concern the sufficiency of talin for activation, whether conformational change without clustering leads to activation, and whether mechanical force is required for molecular extension. Here, we reconstructed physiological integrin activation in vitro and used cellular, biochemical, biophysical, and ultrastructural analyses to show that talin binding is sufficient to activate integrin alphaIIbbeta3. Furthermore, we synthesized nanodiscs, each bearing a single lipid-embedded integrin, and used them to show that talin activates unclustered integrins leading to molecular extension in the absence of force or other membrane proteins. Thus, we provide the first proof that talin binding is sufficient to activate and extend membrane-embedded integrin alphaIIbbeta3, thereby resolving numerous controversies and enabling molecular analysis of reconstructed integrin signaling
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