1,254 research outputs found
Criminal Sanctions for Agricultural Violations of the Clean Water Act
Public enforcement of the Clean Water Act (CWA) has been characterized by the increased use of criminal sanctions over the past decade. This sanctioning trend has developed in direct response to the passage of the Sentencing Reform Act (SRA) as part of the Comprehensive Crime Control Act of 1984. New sentencing guidelines were established in 1987 under which courts were required to impose sentences which reflect the seriousness of the offense, provide just punishment for the offense, and afford adequate deterrence to criminal conduct. Legal trends are documented for both industrial and agricultural violations as a result of applying the new federal sentencing guidelines to CWA cases. The efficiency implications of the SRA are evaluated in the context of a model of the public enforcement of environmental law. It is concluded that fault-based standards of liability and the use of mixed fine/incarceration sanctions are appropriate for agricultural violations of the CWA.Elsevier - Paper presented at the 43rd Annual Conference of the Western Social Science Association - Reno (Nevada) 18 to 21 April 200
The Cosmological Slingshot Scenario: a Stringy Proposal for the Early Time Cosmology
In the Cosmological Slingshot Scenario, our Universe is a D3-brane that
extends in the 4d noncompact directions of a warped Calabi-Yau compactification
of IIB Supergravity. Early time cosmology corresponds to a period in which the
brane moves inside a warped throat where a non-vanishing angular momentum
ensures that the trajectory of the brane has a turning point. The corresponding
induced metric on the D3-brane experiences a cosmological evolution with a
bounce. In this framework, the homogeneity, flatness, and isotropy problems of
standard cosmology might be avoided. The power spectrum of primordial
perturbations of the brane embedding can be found and it is shown to be in
agreement to WMAP data.Comment: Presented at "Ten Years of AdS/CFT: A Workshop Celebrating the Tenth
Anniversary of the Maldacena Conjecture", Buenos Aires, Argentina, 19-21 Dec
200
A New Class of Four-Dimensional N=1 Supergravity with Non-minimal Derivative Couplings
In the N=1 four-dimensional new-minimal supergravity framework, we
supersymmetrise the coupling of the scalar kinetic term to the Einstein tensor.
This coupling, although introduces a non-minimal derivative interaction of
curvature to matter, it does not introduce harmful higher-derivatives. For this
construction, we employ off-shell chiral and real linear multiplets. Physical
scalars are accommodated in the chiral multiplet whereas curvature resides in a
linear one.Comment: 18 pages, version published at JHE
Preferred foliation effects in Quantum General Relativity
We investigate the infrared (IR) effects of Lorentz violating terms in the
gravitational sector using functional renormalization group methods similar to
Reuter and collaborators. The model we consider consists of pure quantum
gravity coupled to a preferred foliation, described effectively via a scalar
field with non-standard dynamics. We find that vanishing Lorentz violation is a
UV attractive fixed-point of this model in the local potential approximation.
Since larger truncations may lead to differing results, we study as a first
example effects of additional matter fields on the RG running of the Lorentz
violating term and provide a general argument why they are small.Comment: 12 pages, no figures, compatible with published versio
sheets impact simulation for safety guards design experiments and correlation for fe explicit models of non alloy steel
Abstract In the last few years, some international standards for the safety of machine tools have been developed improving the ballistic protection of safety guards. The uncontrolled projection of parts of work piece or tools can often cause very dangerous perforations of the safety guards. In such a way specific experimental tests like the ones conducted in EU, have assured the possibility to write appendices of ISO standards for safety guards design of machine tools. These tests are based on impact between a particular standardized projectile, which exemplifies an impacting fragment of variable size and energy, and a flat plate placed in the trajectory of the projectile. The penetration or buckling of the target determines the non-suitability of a particular material of a given thickness, for the design and production of safety guards. However, these tests have following limitations: they are valid only for: a limited type of thickness and materials, a perpendicular impact with flat plates of about 500 mm x 500 mm and when the standardized penetrator is a cylinder with a prismatic head. Another limitation is based on design of real safety guards: difficulties in taking into account curved design of guards such as the ones typically used in the spindles of machine tools. Moreover, it is very difficult to take into account innovative materials different from the ones provided by the standards. It is also impossible to consider projected objects whose geometry is not regular, for example fragmented parts of tools, broken as a result of a wrong manoeuvre of the machine user. The focus of this paper is to give an overview of possible material models usable for FEM explicit virtual testing of safety guards. Correlation between experimental penetration of international standards and numerical tests will be presented as a proof of the possibility to implement reliable testing virtual procedures. It is possible to think of exploring the uncertainty of the standardized tests procedure due to, as an example, non-perpendicular impact of the projectile on the safety guard, using simulations
Polynomial Approach for Filtering and Identification of a Class of Uncertain Systems
Abstract this paper considers the filtering and identification problems for a class of discrete-time uncertain stochastic systems that admit a finite number of linear working modes. It is shown here that this class of uncertain systems can be modeled by using a suitably defined extended system, whose state evolves according to a bilinear model. A polynomial filtering algorithm is derived for such extended system, which readily provides the polynomial estimates of both the original state and the working mode. Simulations show the effectiveness of the proposed approach and the improvements with respect to standard linear filtering algorithms
Late Effects of Disturbed IGF Signaling in Congenital Diseases.
The biologic effects of insulin-like growth factor-1 (IGF-1) are mediated by specific
cell surface receptors. IGF-1 binding to the extracellular -subunits activates the tyrosine
kinase intrinsic to the cytoplasmic portion of the IGF-1 receptor, leading to autophosphorylation
of specific tyrosine residues in the receptor -subunit. One early molecular event that
links the receptor kinase to the biologic actions of IGF-1 is tyrosine phosphorylation of the
insulin receptor substrate family (IRS-1 to -4). IRS acts as a multisite ‘docking’ protein by
binding to downstream signal-transducing molecules. Phosphorylation of multiple tyrosine
residues results in the association of IRS-1 with the Src homology 2 (SH2) domains of other
cytoplasmic signaling proteins, including phosphatidylinositol 3 kinase, Syp, Grb2 and
Nck. By binding to Grb2, IRS proteins couple the IGF-1 receptor to the Ras/mitogenactivated
protein kinase pathway. This pathway regulates cell growth, differentiation and
proliferation. Severe pre- and postnatal growth retardation may arise from abnormalities of
IGF-1 signaling such as IGF-1-binding alterations and IGF-1 receptor mutations. Knockout
studies have shown severe growth impairment in mice lacking IRS family components or
Akt. Finally, in human placentas from pregnancies complicated by intrauterine growth
retardation, multiple alterations of IGF-1-signaling molecules have recently been described
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