25,420 research outputs found
The Pros and Cons of Politically Reversible Semisubstantive Constitutional Rules
Most observers of constitutional adjudication believe that it works in an all-or-nothing way. On this view, the substance of challenged rules is of decisive importance, so that political decision makers may resuscitate invalidated laws only by way of constitutional amendment. This conception of constitutional law is incomplete. In fact, courts often use so-called “semisubstantive” doctrines that focus on the processes that nonjudicial officials have used in adopting constitutionally problematic rules. When a court strikes down a rule by using a motive-centered or legislative-findings doctrine, for example, political decision makers may revive that very rule without need for a constitutional amendment. For such an effort to succeed, however, those decision makers must comply with special, deliberation-enhancing procedural requirements crafted by courts to ensure that constitutional concerns receive fair attention in the lawmaking process. Is semisubstantive review legitimate and sensible? In this Article, the author disentangles—and then responds to—each of ten critiques that judges and scholars have directed at semisubstantive decision making. While acknowledging that most of these critiques have some merit, the author concludes that courts should continue to deploy semisubstantive doctrines as one, but not the only, tool of constitutional review. This approach, it is argued, serves a worthy aim. It protects constitutional values in a meaningful way, while taking due account of the salience of republican self-rule
Fringe field simulations of a non-scaling FFAG accelerator
Fixed-field Alternating Gradient (FFAG) accelerators offer the potential of
high-quality, moderate energy ion beams at low cost. Modeling of these
structures is challenging with conventional beam tracking codes because of the
large radial excursions of the beam and the significance of fringe field
effects. Numerous tune resonances are crossed during the acceleration, which
would lead to beam instability and loss in a storage ring. In a non-scaling
FFAG, the hope is that these resonances can be crossed sufficiently rapidly to
prevent beam loss. Simulations are required to see if this is indeed the case.
Here we simulate a non-scaling FFAG which accelerates protons from 31 to 250
MeV. We assume only that the bending magnets have mid-plane symmetry, with
specified vertical bending field in the mid-plane (y=0). The magnetic field can
be obtained everywhere using a power series expansion, and we develop
mathematical tools for calculating this expansion to arbitrary order when the
longitudinal field profile is given by an Enge function. We compare the use of
a conventional hard-edge fringe with a more accurate, soft-edge fringe field
model. The tune 1/3 resonance is the strongest, and crossing it in the
hard-edge fringe model results in a 21% loss of the beam. Using the soft-edge
fringe model the beam loss is less than 6%.Comment: 12 pages; 12 figure
Factorization in B -> K pi e+e- decays
We derive factorization relations for the transverse helicity amplitudes in
the rare decays B-> K\pi l+l- at leading order in Lambda/m_b, in the
kinematical region with an energetic kaon and a soft pion. We identify and
compute a new contribution of leading order in Lambda/m_b to the B->K\pi l+l-
amplitude, which is not present in the one-body decay B-> K*l+l-. As an
application we study the forward-backward asymmetry (FBA) of the lepton
momentum angular distribution in B-> K\pi l+l- decays away from the K*
resonance. The FBA in these decays has a zero at q0^2 = q0^2(M_{Kpi}), which
can be used, in principle, for determining the Wilson coefficients C_{7,9} and
testing the Standard Model. We point out that the slope of the q0^2(M_{Kpi}^2)
curve contains the same information about the Wilson coefficients as the
location of the zero, but is less sensitive to unknown nonperturbative
dynamics. We estimate the location of the zero at leading order in
factorization, and using a resonant model for the B -> K\pi l+l-
nonfactorizable amplitude.Comment: 16 pages, 5 figures. Version to appear in Physical Review D. One new
observable introduced and considered - the slope of the zero of the
forward-backward asymmetry as function of the K\pi invariant mas
The Cost of Caring for Young Children
This study examines the "cost burden" of child care, defined as day care expenses divided by after-tax income. Data are from the wave 10 core and child care topical modules to the 1996 Survey of Income and Program Participation. We estimate that the average child under six years of age lives in a family that spends 4.9 percent of after-tax income on day care. However, this conceals wide variation: 63 percent of such children reside in families with no child care expenses and 10 percent are in families where the cost burden exceeds 16 percent. The burden is typically greater in single-parent than married-couple families but is not systematically related to a measure of socioeconomic status that we construct. One reason for this is that disadvantaged families use lower cost modes and pay less per hour for given types of care. The cost burden would be much less equal without low cost (presumably subsidized) formal care focused on needy families, as well as government tax and transfer policies that redistribute income towards them.
Welfare, the Earned Income Tax Credit, and the Labor Supply of Single Mothers
During 1984-96, welfare and tax policy changed dramatically. The Earned Income Tax Credit was expanded, welfare benefits were cut, welfare time limits were added and cases were terminated, Medicaid for the working poor was expanded, training programs were redirected, and subsidized or free child care was expanded. Many of the program changes were intended to encourage low income women to work. During this same time period there were unprecedented increases in the employment and hours of single mothers, particularly those with young children. In this paper, we first document these large changes in policies and employment. We then examine if the policy changes are the reason for the large increases in single mothers' labor supply. We find evidence that a large share of the increase in work by single mothers can be attributed to the EITC, with smaller shares for welfare benefit reductions, welfare waivers, changes in training programs, and child care expansions. We also find that most of these policies increased hours worked. Our results indicate that financial incentives through the tax and welfare systems have substantial effects on single mothers' labor supply decisions.
The Impact of Late-Career Health and Employment Shocks on Social Security and Other Wealth
About one-quarter of workers age 51 to 55 in 1992 developed health-related work limitations and about one-fifth were laid off from their jobs before age 62. Although late-career health and employment shocks often derail retirement savings plans, Social Security's disability insurance, spouse and survivor benefits, and progressive benefit formula provide important protections. In fact, health shocks increase Social Security's lifetime value, primarily because the system's disability insurance allows some disabled workers to collect benefits before age 62. However, if the system's disability insurance program did not exist, the onset of health-related work limitations would substantially reduce Social Security wealth
Analysis of Iterative Methods for the Steady and Unsteady Stokes Problem: Application to Spectral Element Discretizations
A new and detailed analysis of the basic Uzawa algorithm for decoupling of the pressure and the velocity in the steady and unsteady Stokes operator is presented. The paper focuses on the following new aspects: explicit construction of the Uzawa pressure-operator spectrum for a semiperiodic model problem; general relationship of the convergence rate of the Uzawa procedure to classical inf-sup discretization analysis; and application of the method to high-order variational discretization
Study of the Anatomy of the Alimentary Canal of Brochymena quadripustulata (Hemiptera:Pentatomidae)
An anatomical study of the alimentary canal and associated salivary apparatus was conducted for the pentatomid, Brochymena quadripustulata. The esophagus, ventriculus, pylorus, rectum, principal salivary glands and ducts are described and illustrated. Described structures of Brochymena quadripustulata are compared with various species of pentatomids and other hemipterans
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