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Scientific information has become a centralr ationalef or environmental regulation, and scientific uncertainty is viewed as a major obstacle in developing, justifying, and enforcing environmental laws and policies. In the context of environmental regulation, scientific information may be analyzed as subject to both supply and demand. A regulatory system that supplies more scientific information than it demands can operate effectively to impose protective regulation. By contrast, a system that demands more information than it supplies will face a data gap and will fail to accomplish its protective goals. The data gap can be addressed by applying regulatory techniques that increase the supply of data by providing more information (\u27filling the gap) or that reduce the demand by permitting regulation to proceed despite uncertainty and incomplete information ( bridging the gap).
Environmental law is also structured by the divide between pollution control and chemical regulation on the one hand, and resource management on the other. In addressing the data gap, therefore, it is necessary to distinguish not only between supply and demand, but also between chemical and conservation issues. The existence of a data gap between the scientific information necessary for effective environmental regulation and the information available to regulators and the public presents an opportunity to study the causes and extent of the differences in the chemical and conservation regulatory systems.
Missing Information: The Scientific Data Gap in Conservation and Chemical Regulation, Symposium held on March 24, 2006 at Indiana University School of Law- Bloomington
The role of Volatile Anesthetics in Cardioprotection: a systematic review.
This review evaluates the mechanism of volatile anesthetics as cardioprotective agents in both clinical and laboratory research and furthermore assesses possible cardiac side effects upon usage. Cardiac as well as non-cardiac surgery may evoke perioperative adverse events including: ischemia, diverse arrhythmias and reperfusion injury. As volatile anesthetics have cardiovascular effects that can lead to hypotension, clinicians may choose to administer alternative anesthetics to patients with coronary artery disease, particularly if the patient has severe preoperative ischemia or cardiovascular instability. Increasing preclinical evidence demonstrated that administration of inhaled anesthetics - before and during surgery - reduces the degree of ischemia and reperfusion injury to the heart. Recently, this preclinical data has been implemented clinically, and beneficial effects have been found in some studies of patients undergoing coronary artery bypass graft surgery. Administration of volatile anesthetic gases was protective for patients undergoing cardiac surgery through manipulation of the potassium ATP (KATP) channel, mitochondrial permeability transition pore (mPTP), reactive oxygen species (ROS) production, as well as through cytoprotective Akt and extracellular-signal kinases (ERK) pathways. However, as not all studies have demonstrated improved outcomes, the risks for undesirable hemodynamic effects must be weighed against the possible benefits of using volatile anesthetics as a means to provide cardiac protection in patients with coronary artery disease who are undergoing surgery
Cosmology and astrophysics from relaxed galaxy clusters - IV: Robustly calibrating hydrostatic masses with weak lensing
This is the fourth in a series of papers studying the astrophysics and
cosmology of massive, dynamically relaxed galaxy clusters. Here, we use
measurements of weak gravitational lensing from the Weighing the Giants project
to calibrate Chandra X-ray measurements of total mass that rely on the
assumption of hydrostatic equilibrium. This comparison of X-ray and lensing
masses provides a measurement of the combined bias of X-ray hydrostatic masses
due to both astrophysical and instrumental sources. Assuming a fixed cosmology,
and within a characteristic radius (r_2500) determined from the X-ray data, we
measure a lensing to X-ray mass ratio of 0.96 +/- 9% (stat) +/- 9% (sys). We
find no significant trends of this ratio with mass, redshift or the
morphological indicators used to select the sample. In accordance with
predictions from hydro simulations for the most massive, relaxed clusters, our
results disfavor strong, tens-of-percent departures from hydrostatic
equilibrium at these radii. In addition, we find a mean concentration of the
sample measured from lensing data of c_200 = . Anticipated
short-term improvements in lensing systematics, and a modest expansion of the
relaxed lensing sample, can easily increase the measurement precision by
30--50%, leading to similar improvements in cosmological constraints that
employ X-ray hydrostatic mass estimates, such as on Omega_m from the cluster
gas mass fraction.Comment: 13 pages. Submitted to MNRAS. Comments welcom
Coyote, Canis latrans - Rio Grande Turkey, Meleagris gallopavo intermedia, Interactions
Coyotes (Canis latrans) are widely known to be predators of Wild Turkeys (Meleagris gallopauo sspp.). We describe two observations of single Coyotes coming within 10 m of feeding Wild Turkey flocks without attempting to predate them in Stevens County, Kansas. We relate these observations to Coyote predation on turkeys and mobbing behavior
Generalized Buneman pruning for inferring the most parsimonious multi-state phylogeny
Accurate reconstruction of phylogenies remains a key challenge in
evolutionary biology. Most biologically plausible formulations of the problem
are formally NP-hard, with no known efficient solution. The standard in
practice are fast heuristic methods that are empirically known to work very
well in general, but can yield results arbitrarily far from optimal. Practical
exact methods, which yield exponential worst-case running times but generally
much better times in practice, provide an important alternative. We report
progress in this direction by introducing a provably optimal method for the
weighted multi-state maximum parsimony phylogeny problem. The method is based
on generalizing the notion of the Buneman graph, a construction key to
efficient exact methods for binary sequences, so as to apply to sequences with
arbitrary finite numbers of states with arbitrary state transition weights. We
implement an integer linear programming (ILP) method for the multi-state
problem using this generalized Buneman graph and demonstrate that the resulting
method is able to solve data sets that are intractable by prior exact methods
in run times comparable with popular heuristics. Our work provides the first
method for provably optimal maximum parsimony phylogeny inference that is
practical for multi-state data sets of more than a few characters.Comment: 15 page
Ventilator-associated pneumonia in PICU – how are we doing?
Introduction. Ventilator-associated pneumonia (VAP) is a common hospital-acquired infection in children, leading to an increase in morbidity and mortality. A previous study in 2013 showed that VAP rates decreased dramatically after implementation of a VAP bundle and appointing a VAP coordinator. As part of a ‘Plan, Do, Study, Act’ cycle, it was necessary to evaluate the efficacy of these interventions.
Objective. To evaluate the VAP rate in the paediatric intensive care unit (PICU) over 2 years (2017 - 2018), and to describe the causative organisms and antibiotic sensitivity/resistance patterns during this period.
Methods. This was a retrospective, descriptive study using the existing PICU VAP database as well as clinical folders.
Results. Over the 2 years, 31 VAP cases were identified. The VAP rate for 2017 was 4.0/1 000 ventilator days and 5.4/1 000 ventilator days for 2018. Compliance with the VAP bundle was 68% in 2017 and 70% in 2018. The median (interquartile range (IQR)) duration of ventilation in 2017 was 9 (6 -12) days and 15 (11 - 28) days in 2018. The median (IQR) length of PICU stay in 2017 was 11 (8 - 22) days and 25 (17 - 37) days in 2018. The most common cultured organism was an extended-spectrum beta-lactamase (ESBL) Klebsiella pneumoniae sensitive to amikacin and carbapenems. Conclusion. Our VAP rate has not decreased since 2013. It is imperative that we improve compliance with the VAP bundle, in order to reduce VAP rates. K. pneumoniae and Pseudomonas aeruginosa were the most common organisms causing VAPs and empiric use of piptazobactam and amikacin is still appropriate
A Circumbinary Planet in Orbit Around the Short-Period White-Dwarf Eclipsing Binary RR Cae
By using six new determined mid-eclipse times together with those collected
from the literature, we found that the Observed-Calculated (O-C) curve of RR
Cae shows a cyclic change with a period of 11.9 years and an amplitude of
14.3s, while it undergoes an upward parabolic variation (revealing a long-term
period increase at a rate of dP/dt =+4.18(+-0.20)x10^(-12). The cyclic change
was analyzed for the light-travel time effect that arises from the
gravitational influence of a third companion. The mass of the third body was
determined to be M_3*sin i' = 4.2(+-0.4) M_{Jup} suggesting that it is a
circumbinary giant planet when its orbital inclination is larger than 17.6
degree. The orbital separation of the circumbinary planet from the central
eclipsing binary is about 5.3(+-0.6)AU. The period increase is opposite to the
changes caused by angular momentum loss via magnetic braking or/and
gravitational radiation, nor can it be explained by the mass transfer between
both components because of its detached configuration. These indicate that the
observed upward parabolic change is only a part of a long-period (longer than
26.3 years) cyclic variation, which may reveal the presence of another giant
circumbinary planet in a wide orbit.Comment: It will be published in the MNRA
Crotalus atrox venom preconditioning increases plasma fibrinogen and reduces perioperative hemorrhage in a rat model of surgical brain injury.
Perioperative bleeding is a potentially devastating complication in neurosurgical patients, and plasma fibrinogen concentration has been identified as a potential modifiable risk factor for perioperative bleeding. The aim of this study was to evaluate preconditioning with Crotalus atrox venom (Cv-PC) as potential preventive therapy for reducing perioperative hemorrhage in the rodent model of surgical brain injury (SBI). C. atrox venom contains snake venom metalloproteinases that cleave fibrinogen into fibrin split products without inducing clotting. Separately, fibrinogen split products induce fibrinogen production, thereby elevating plasma fibrinogen levels. Thus, the hypothesis was that preconditioning with C. atrox venom will produce fibrinogen spilt products, thereby upregulating fibrinogen levels, ultimately improving perioperative hemostasis during SBI. We observed that Cv-PC SBI animals had significantly reduced intraoperative hemorrhage and postoperative hematoma volumes compared to those of vehicle preconditioned SBI animals. Cv-PC animals were also found to have higher levels of plasma fibrinogen at the time of surgery, with unchanged prothrombin time. Cv-PC studies with fractions of C. atrox venom suggest that snake venom metalloproteinases are largely responsible for the improved hemostasis by Cv-PC. Our findings indicate that Cv-PC increases plasma fibrinogen levels and may provide a promising therapy for reducing perioperative hemorrhage in elective surgeries
Star-Forming Brightest Cluster Galaxies at 0.25 < z < 1.25: A Transitioning Fuel Supply
We present a multi-wavelength study of 90 brightest cluster galaxies (BCGs)
in a sample of galaxy clusters selected via the Sunyaev Zel'dovich effect by
the South Pole Telescope, utilizing data from various ground- and space-based
facilities. We infer the star formation rate (SFR) for the BCG in each cluster,
based on the UV and IR continuum luminosity, as well as the [O II] emission
line luminosity in cases where spectroscopy is available, finding 7 systems
with SFR > 100 Msun/yr. We find that the BCG SFR exceeds 10 Msun/yr in 31 of 90
(34%) cases at 0.25 < z < 1.25, compared to ~1-5% at z ~ 0 from the literature.
At z > 1, this fraction increases to 92(+6)(-31)%, implying a steady decrease
in the BCG SFR over the past ~9 Gyr. At low-z, we find that the specific star
formation rate in BCGs is declining more slowly with time than for field or
cluster galaxies, most likely due to the replenishing fuel from the cooling ICM
in relaxed, cool core clusters. At z > 0.6, the correlation between cluster
central entropy and BCG star formation - which is well established at z ~ 0 -
is not present. Instead, we find that the most star-forming BCGs at high-z are
found in the cores of dynamically unrelaxed clusters. We investigate the
rest-frame near-UV morphology of a subsample of the most star-forming BCGs
using data from the Hubble Space Telescope, finding complex, highly asymmetric
UV morphologies on scales as large as ~50-60 kpc. The high fraction of
star-forming BCGs hosted in unrelaxed, non-cool core clusters at early times
suggests that the dominant mode of fueling star formation in BCGs may have
recently transitioned from galaxy-galaxy interactions to ICM cooling.Comment: 20 pages, 10 figures. Submitted for publication in ApJ. Comments
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