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Proposed Keystone XL Pipeline: Legal Issues
[Excerpt] In 2008, TransCanada Corp. applied for a presidential permit from the State Department to construct and operate an oil pipeline across the U.S.-Canada border in a project known as Keystone XL. The Keystone XL pipeline would transport oil produced from oil sands in Alberta,Canada, to Gulf Coast refineries. The permit application was subjected to review by the State Department pursuant to executive branch authority over cross-border pipeline facilities as articulated in Executive Order 13337.
After several phases of review, on November 10, 2011, the State Department announced that it would seek additional information about alternative pipeline routes before it could move forward with a national interest determination. In response, several pieces of legislation were introduced, including Title V of the Temporary Payroll Tax Cut Continuation Act of 2011. Title V dictated that President must grant the Keystone XL pipeline permit within 60 days of the law’s enactment, unless the President determined that the pipeline is not in the national interest. If the President did not make a national interest determination and took no action to grant the permit, then the law provided that the permit “shall be in effect by operation of law.” The Temporary Payroll Tax Cut Continuation Act of 2011 (P.L. 112-78), including Title V addressing the Keystone XL permit, was enacted on December 23, 2011.
Pursuant to the requirements of Title V, on January 18, 2012, the State Department recommended that “the presidential permit for the proposed Keystone XL pipeline be denied and, that at this time, the TransCanada Keystone XL Pipeline be determined not to serve the national interest. ”The same day, the President stated his determination that the Keystone XL pipeline project“ would not serve the national interest.
”New legislative activity with respect to the permitting of border-crossing facilities, a subject previously handled exclusively by the executive branch, has triggered inquiries as to whether this raises constitutional issues related to the jurisdiction of the two branches over such facilities. Additionally, as states have begun to contemplate taking action with respect to the pipeline siting, some have questioned whether state siting of a pipeline is preempted by federal law. Others argue that states dictating the route of the pipeline violates the dormant Commerce Clause of the Constitution which, among other things, prohibits one state from acting to protect its own interests to the detriment of other states.
This report reviews those legal issues. First, it suggests that legislation related to cross-border facility permitting is unlikely to raise significant constitutional questions, despite the fact that such permits have traditionally been handled by the executive branch alone pursuant to its constitutional “foreign affairs” authority. Next, it observes generally that state oversight of pipeline siting decisions does not appear to violate existing federal law or the Constitution. Finally, the report suggests that State Department’s implementation of the existing authority to issue presidential permits appears to allow for judicial review of its National Environmental Policy Act determinations
Evolution of "51Peg b-like" Planets
About one-quarter of the extrasolar giant planets discovered so far have
orbital distances smaller than 0.1 AU. These ``51Peg b-like'' planets can now
be directly characterized, as shown by the planet transiting in front the star
HD209458. We review the processes that affect their evolution.
We apply our work to the case of HD209458b, whose radius has been recently
measured. We argue that its radius can be reproduced only when the deep
atmosphere is assumed to be unrealistically hot. When using more realistic
atmospheric temperatures, an energy source appears to be missing in order to
explain HD209458b's large size. The most likely source of energy available is
not in the planet's spin or orbit, but in the intense radiation received from
the parent star. We show that the radius of HD209458b can be reproduced if a
small fraction (~1%) of the stellar flux is transformed into kinetic energy in
the planetary atmosphere and subsequently converted to thermal energy by
dynamical processes at pressures of tens of bars.Comment: 11 pages including 9 figures. A&A, in press. Also available at
http://www.obs-nice.fr/guillot/pegasi-planets
Pulsational Analysis of the Cores of Massive Stars and its Relevance to Pulsar Kicks
The mechanism responsible for the natal kicks of neutron stars continues to
be a challenging problem. Indeed, many mechanisms have been suggested, and one
hydrodynamic mechanism may require large initial asymmetries in the cores of
supernova progenitor stars. Goldreich, Lai, & Sahrling (1997) suggested that
unstable g-modes trapped in the iron (Fe) core by the convective burning layers
and excited by the -mechanism may provide the requisite asymmetries.
We perform a modal analysis of the last minutes before collapse of published
core structures and derive eigenfrequencies and eigenfunctions, including the
nonadiabatic effects of growth by nuclear burning and decay by both neutrino
and acoustic losses. In general, we find two types of g-modes: inner-core
g-modes, which are stabilized by neutrino losses and outer-core g-modes which
are trapped near the burning shells and can be unstable. Without exception, we
find at least one unstable g-mode for each progenitor in the entire mass range
we consider, 11 M_{\sun} to 40 M_{\sun}. More importantly, we find that the
timescales for growth and decay are an order of magnitude or more longer than
the time until the commencement of core collapse. We conclude that the
-mechanism may not have enough time to significantly amplify core
g-modes prior to collapse.Comment: 32 pages including 12 color figures and 2 tables, submitted to Ap
Quantitative shadowgraphy and proton radiography for large intensity modulations
Shadowgraphy is a technique widely used to diagnose objects or systems in
various fields in physics and engineering. In shadowgraphy, an optical beam is
deflected by the object and then the intensity modulation is captured on a
screen placed some distance away. However, retrieving quantitative information
from the shadowgrams themselves is a challenging task because of the non-linear
nature of the process. Here, a novel method to retrieve quantitative
information from shadowgrams, based on computational geometry, is presented for
the first time. This process can be applied to proton radiography for electric
and magnetic field diagnosis in high-energy-density plasmas and has been
benchmarked using a toroidal magnetic field as the object, among others. It is
shown that the method can accurately retrieve quantitative parameters with
error bars less than 10%, even when caustics are present. The method is also
shown to be robust enough to process real experimental results with simple pre-
and post-processing techniques. This adds a powerful new tool for research in
various fields in engineering and physics for both techniques
X-ray and optical variability of Seyfert 1 galaxies as observed with XMM-Newton
We have examined simultaneous X-ray and optical light curves of a sample of
eight nearby Seyfert 1 galaxies observed using the EPIC X-ray cameras and
Optical Monitor on board XMM. The observations span ~1 day and revealed optical
variability in four of the eight objects studied. In all cases, the X-ray
variability amplitude exceeded that of the optical both in fractional and
absolute luminosity terms. No clearly significant correlations were detected
between wavebands using cross correlation analysis. We conclude that, in three
of the four objects in which optical variability was detected, reprocessing
mechanisms between wavebands do not dominate either the optical or X-ray
variability on the time-scales probed.Comment: 9 pages, 2 figures, accepted for publication in MNRA
Adiabatic Evolution of Mass-losing Stars
We have calculated the equilibrium properties of a star in a circular,
equatorial orbit about a Super-Massive Black Hole (SMBH), when the star fills
and overflows its Roche lobe. The mass transfer time scale is anticipated to be
long compared with the dynamical time and short compared with the thermal time
of the star, so that the entropy as a function of the interior mass is
conserved. We have studied how the stellar entropy, pressure, radius, mean
density, and orbital angular momentum vary when the star is evolved
adiabatically, for a representative set of stars. We have shown that the
stellar orbits change with the stellar mean density. Therefore, sun-like stars,
upper main sequence stars and red giants will spiral inward and then outward
with respect to the hole in this stable mass transfer process, while lower main
sequence stars, brown dwarfs and white dwarfs will always spiral outward.Comment: 8 pages, 19 figures, submitted to MNRA
Possible astrophysical clues of dark matter
The physics of the supernova may provide a clue of the cosmological dark
matter. In the absence of new physics, the supernova calculations do not
explain the observed velocities of pulsars. However, if there exists a singlet
fermion with mass in the 1-20 keV range and a small mixing with neutrinos, this
particle could be emitted asymmetrically from a cooling neutron star in the
event of a supernova explosion. The asymmetry could explain the long-standing
puzzle of pulsar velocities. The same particle could be the dark matter.
Observations of X-ray telescopes, as well as a future detection of
gravitational waves from a nearby supernova can confirm or rule out this
possibility.Comment: 6 pages, 1 figure; talk presented at the 6th UCLA Symposium on
Sources and Detection of Dark Matter and Dark Energy in the Universe (Dark
Matter 2004), Marina del Rey, California, February 18-20, 200
The South African national non-natural mortality surveillance system rationale, pilot results and evaluation
Background. While individual mortuaries have recorded data for non-natural deaths in time-limited studies, there have been no systematic efforts to draw forensic-medical services and state mortuaries into a nationwide fatal injury surveillance system. Beginning in June 1998, the National Non-Natural Mortality Surveillance System (NMSS) commenced pilot operation.Objective. To evaluate the NMSS and illustrate its utility from sample findings.Design. Data entered into the system by mortuary staff were checked against a random sample of cases for which separate forms were completed by an independent researcher. Process observations and follow-up with data users were used to assess the system's acceptability, timeliness and data usefulness.Setting. Eighteen mortuaries in six provinces representing approximately 35 000 cases per year, or around 50% of all non-natural deaths.Participants. The National Departments of Health; Safety and Security; and Arts, Culture, Science and Technology; national and provincial forensic medico-Iegal services; the South African Police Services; universities and science research councils.Main outcome measures. Surveillance system simplicity, flexibility, acceptability, sensitivity, positive predictive value, representativeness, timeliness, data usefulness and resources.Results. The NMSS was established at 10 target sites. Lack of equipment, personnel resistance, and closure of some mortuaries prevented implementation in the remaining eight mortuaries. Sensitivity was internally assessed and ranged from 65% to 95% for manner of death. Positive predictive value was also internally measured, and ranged from 74% to 80% for manner of death and from 71% to 82% for mechanism of death. TImeliness was good, and basic reports covering most items were available 6 weeks after a case had been examined. While staff found the system simple, acceptability depended on the individuals involved at different mortuaries, and the system was compromised to some extent by bureaucratic barriers. End users found the data to be of great value. NMSS set-up costs totalled approximately R26 000 per mortuary, and it is estimated that maintenance costs will be R8.00 per case registered.Conclusions. With minimal resources, the NMSS uses existing investigative procedures to describe and report the epidemiology of fatal injuries. The pilot study demonstrates the feasibility of the system, and identifies the need to remove organisational constraints and individual barriers if it is to be sustained and expanded beyond the pilot sites
Microbiota regulates type 1 diabetes through Toll-like receptors
Deletion of the innate immune adaptor myeloid differentiation primary response gene 88 (MyD88) in the nonobese diabetic (NOD) mouse model of type 1 diabetes (T1D) results in microbiota-dependent protection from the disease: MyD88-negative mice in germ-free (GF), but not in specific pathogen-free conditions develop the disease. These results could be explained by expansion of particular protective bacteria (“specific lineage hypothesis”) or by dominance of negative (tolerizing) signaling over proinflammatory signaling (“balanced signal hypothesis”) in mutant mice. Here we found that colonization of GF mice with a variety of intestinal bacteria was capable of reducing T1D in MyD88-negative (but not wild-type NOD mice), favoring the balanced signal hypothesis. However, the receptors and signaling pathways involved in prevention or facilitation of the disease remained unknown. The protective signals triggered by the microbiota were revealed by testing NOD mice lacking MyD88 in combination with knockouts of several critical components of innate immune sensing for development of T1D. Only MyD88- and TIR-domain containing adapter inducing IFN β (TRIF) double deficient NOD mice developed the disease. Thus, TRIF signaling (likely downstream of Toll-like receptor 4, TLR4) serves as one of the microbiota-induced tolerizing pathways. At the same time another TLR (TLR2) provided prodiabetic signaling by controlling the microbiota, as reduction in T1D incidence caused by TLR2 deletion was reversed in GF TLR2-negative mice. Our results support the balanced signal hypothesis, in which microbes provide signals that both promote and inhibit autoimmunity by signaling through different receptors, including receptors of the TLR family
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