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A partnership-based, whole-watershed approach to climate adaptation in Acadia National Park
Changes in climate and associated changes in seasonality, invasive plants and insects, and visitation are stressing ecosystems and infrastructure in Acadia National Park. Over the past five years, park staff and partners have begun taking an interdisciplinary, partnership-based approach to assessing baseline conditions, identifying stresses, developing climate change scenarios, and restoring the ecological and cultural integrity and resilience of whole watersheds. The approach contrasts with past resource management in which managers frequently tackled problems with minimal coordination between disciplines (e.g., water, wildlife, cultural resources, and maintenance) and locations. The result has been a series of projects that have begun to measurably improve the health of one of the park’s most visited and iconic watersheds: the Cromwell Brook watershed, which includes Sieur de Monts (Acadia began in 1916 as Sieur de Monts National Monument) and the Great Meadow, and whose namesake waterway flows through the gateway town of Bar Harbor. Projects (inside and out of the park) have included rehabilitating a historic spring pool, replacing undersized culverts with open-bottom bridges, removing a poorly sited septic system, removing invasive plants, restoring native wetland, establishing monitoring to assess changes in watershed health, and working with the town and other stakeholders to plan future projects that would further improve the health of Great Meadow and downstream areas in Bar Harbor. The combination of planning; monitoring; restoring healthy, functioning ecological communities; and minimizing stresses from human infrastructure and visitation offer the best chance of main- taining Acadia National Park for the enjoyment of future generations
A Comparative Study of the Formation of Aromatics in Rich Methane Flames Doped by Unsaturated Compounds
For a better modeling of the importance of the different channels leading to
the first aromatic ring, we have compared the structures of laminar rich
premixed methane flames doped with several unsaturated hydrocarbons: allene and
propyne, because they are precursors of propargyl radicals which are well known
as having an important role in forming benzene, 1,3-butadiene to put in
evidence a possible production of benzene due to reactions of C4 compounds,
and, finally, cyclopentene which is a source of cyclopentadienylmethylene
radicals which in turn are expected to easily isomerizes to give benzene. These
flames have been stabilized on a burner at a pressure of 6.7 kPa (50 Torr)
using argon as dilutant, for equivalence ratios (?) from 1.55 to 1.79. A unique
mechanism, including the formation and decomposition of benzene and toluene,
has been used to model the oxidation of allene, propyne, 1,3 butadiene and
cyclopentene. The main reaction pathways of aromatics formation have been
derived from reaction rate and sensitivity analyses and have been compared for
the three types of additives. These combined analyses and comparisons can only
been performed when a unique mechanism is available for all the studied
additives
Optical/Near-Infrared Observations of GRO J1744-28
We present results from a series of optical (g and r-band) and near-infrared
(K'-band) observations of the region of the sky including the entire XTE and
ROSAT error circles for the ``Bursting Pulsar'' GRO J1744-28. These data were
taken with the Astrophysical Research Consortium's 3.5-m telescope at Apache
Point Observatory and with the 2.2-m telescope at the European Southern
Observatory. We see no new object, nor any significant brightening of any known
object, in these error circles, with the exception of an object detected in our
8 February 1996 image. This object has already been proposed as a near-infrared
counterpart to GRO J1744-28. While it is seen in only two of our ten 8 February
frames, there is no evidence that this is an instrumental artifact, suggesting
the possibility of near-infrared flares from GRO J1744-28, similar to those
that have been reported from the Rapid Burster. The distance to the ``Bursting
Pulsar'' must be more than 2 kpc, and we suggest that it is more than 7 kpc.Comment: 21 pages, 5 JPEG plates, 2 postscript figures. This paper will appear
in the May 1, 1997 edition of the Astrophysical Journa
MicroRNA profiling reveals marker of motor neuron disease in ALS models
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder marked by the loss of motor neurons (MNs) in the brain and spinal cord, leading to fatally debilitating weakness. Because this disease predominantly affects MNs, we aimed to characterize the distinct expression profile of that cell type to elucidate underlying disease mechanisms and to identify novel targets that inform on MN health during ALS disease time course. microRNAs (miRNAs) are short, noncoding RNAs that can shape the expression profile of a cell and thus often exhibit cell-type-enriched expression. To determine MN-enriched miRNA expression, we used Cre recombinase-dependent miRNA tagging and affinity purification in mice. By defining thein vivomiRNA expression of MNs, all neurons, astrocytes, and microglia, we then focused on MN-enriched miRNAs via a comparative analysis and found that they may functionally distinguish MNs postnatally from other spinal neurons. Characterizing the levels of the MN-enriched miRNAs in CSF harvested from ALS models of MN disease demonstrated that one miRNA (miR-218) tracked with MN loss and was responsive to an ALS therapy in rodent models. Therefore, we have used cellular expression profiling tools to define the distinct miRNA expression of MNs, which is likely to enrich future studies of MN disease. This approach enabled the development of a novel, drug-responsive marker of MN disease in ALS rodents.SIGNIFICANCE STATEMENTAmyotrophic lateral sclerosis (ALS) is a neurodegenerative disease in which motor neurons (MNs) in the brain and spinal cord are selectively lost. To develop tools to aid in our understanding of the distinct expression profiles of MNs and, ultimately, to monitor MN disease progression, we identified small regulatory microRNAs (miRNAs) that were highly enriched or exclusive in MNs. The signal for one of these MN-enriched miRNAs is detectable in spinal tap biofluid from an ALS rat model, where its levels change as disease progresses, suggesting that it may be a clinically useful marker of disease status. Furthermore, rats treated with ALS therapy have restored expression of this MN RNA marker, making it an MN-specific and drug-responsive marker for ALS rodents.</jats:p
The effect of antiretroviral therapy on all-cause mortality, generalized to persons diagnosed with HIV in the USA, 2009–11
Background: Although antiretroviral therapy (ART) is known to be protective against HIV-related mortality, the expected magnitude of effect is unclear because existing estimates of the effect of ART may not directly generalize to recently HIV-diagnosed persons
Fast and Credible Likelihood-Free Cosmology with Truncated Marginal Neural Ratio Estimation
Sampling-based inference techniques are central to modern cosmological data
analysis; these methods, however, scale poorly with dimensionality and
typically require approximate or intractable likelihoods. In this paper we
describe how Truncated Marginal Neural Ratio Estimation (TMNRE) (a new approach
in so-called simulation-based inference) naturally evades these issues,
improving the efficiency, scalability, and trustworthiness
of the inferred posteriors. Using measurements of the Cosmic Microwave
Background (CMB), we show that TMNRE can achieve converged posteriors using
orders of magnitude fewer simulator calls than conventional Markov Chain Monte
Carlo (MCMC) methods. Remarkably, the required number of samples is effectively
independent of the number of nuisance parameters. In addition, a property
called \emph{local amortization} allows the performance of rigorous statistical
consistency checks that are not accessible to sampling-based methods. TMNRE
promises to become a powerful tool for cosmological data analysis, particularly
in the context of extended cosmologies, where the timescale required for
conventional sampling-based inference methods to converge can greatly exceed
that of simple cosmological models such as CDM. To perform these
computations, we use an implementation of TMNRE via the open-source code
\texttt{swyft}.Comment: v2: accepted journal version. v1: 37 pages, 13 figures.
\texttt{swyft} is available at https://github.com/undark-lab/swyft, and
demonstration code for cosmological examples is available at
https://github.com/acole1221/swyft-CM
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