886 research outputs found
USDA Forest Service Clark Fork River Basin Monitoring
I am pleased to be here to share with you Forest Service water quality monitoring activities in the Clark Fork River basin. Throughout the day, we have heard about the many and varied studies and approaches to monitoring water quality in the Clark Fork River. It is important that this information be brought together and shared so that we can understand the cumulative impacts from all ownerships and activities on the Clark Fork River. Under- standing the cumulative impacts is paramount to the management of the water resource in the Clark Fork basin.
As you may know, there are six National Forests that occupy portions of the Clark Fork basin: Flathead, Kootenai, Lolo, Bitterroot, Helena, and Deerlodge. These Forests encompass substantial acres of the watershed and contribute significantly to the flows in the river. These areas are an essential part of the headwaters of the Clark Fork.
Since we have heard a considerable amount of information regarding the results of studies and monitoring, I would like to use my limited time to give you an overview of Forest Service water quality monitoring activities. For this discussion I would like to take a moment to discuss monitoring activities as they relate to National Forest land management activities. Monitoring on National Forest lands can be categorized into three basic kinds. These are broadly described as (I) administration of on-the-ground land management activities, (2) hydrologic monitoring, and (3) aquatic monitoring. Of the three, it is extremely important that we place a high value on supervision of land management activities on-the-ground as essential to the protection of water resources
Flutter Boundary Identification From Simulation Time Histories
While there has been much recent progress in simulating nonlinear aeroelastic systems, and in predicting many of the aeroelastic phenomena of concern in transport aircraft design (i.e. transonic flutter buckets), the utility of a simulation in generating an understanding of the flutter behavior is limited. This is due in part to the high cost of generating these simulations; and the implied limitation on the number of conditions that can be analyzed, but there are also some difficulties introduced by the very nature of a simulation. Flutter engineers have traditionally worked in the frequency domain, and are accustomed to describing the flutter behavior of an airplane in terms of its V-G and V-F (or Q-G and Q-F) plots and flutter mode shapes. While the V-G and V-F plots give information about how the dynamic response of an airplane changes as the airspeed is increased, the simulation only gives information about one isolated condition (Mach, airspeed, altitude, etc.). Therefore, where a traditional flutter analysis can let the engineer determine an airspeed at which an airplane becomes unstable, while a simulation only serves as a binary check: either the airplane is fluttering at this condition, or it is not. In this document, a new technique is described in which system identification is used to easily extract modal frequencies and damping ratios from simulation time histories, and shows how the identified parameters can be used to determine the variation in frequency and dampin,o ratio as the airspeed is changed. This technique not only provides the flutter engineer with added insight into the aeroelastic behavior of the airplane, but it allows calculation of flutter mode shapes, and allows estimation of flutter boundaries while minimizing the number of simulations required
Violation of the Leggett-Garg inequality with weak measurements of photons
By weakly measuring the polarization of a photon between two strong
polarization measurements, we experimentally investigate the correlation
between the appearance of anomalous values in quantum weak measurements, and
the violation of realism and non-intrusiveness of measurements. A quantitative
formulation of the latter concept is expressed in terms of a Leggett-Garg
inequality for the outcomes of subsequent measurements of an individual quantum
system. We experimentally violate the Leggett-Garg inequality for several
measurement strengths. Furthermore, we experimentally demonstrate that there is
a one-to-one correlation between achieving strange weak values and violating
the Leggett-Garg inequality.Comment: 5 pages, 4 figure
Weak measurement of photon polarization by back-action induced path interference
The essential feature of weak measurements on quantum systems is the
reduction of measurement back-action to negligible levels. To observe the
non-classical features of weak measurements, it is therefore more important to
avoid additional back-action errors than it is to avoid errors in the actual
measurement outcome. In this paper, it is shown how an optical weak measurement
of diagonal (PM) polarization can be realized by path interference between the
horizontal (H) and vertical (V) polarization components of the input beam. The
measurement strength can then be controlled by rotating the H and V
polarizations towards each other. This well-controlled operation effectively
generates the back-action without additional decoherence, while the visibility
of the interference between the two beams only limits the measurement
resolution. As the experimental results confirm, we can obtain extremely high
weak values, even at rather low visibilities. Our method therefore provides a
realization of weak measurements that is extremely robust against experimental
imperfections.Comment: 11 pages, 3 figure
Facebook's Mobile Career
At the end of its first decade, Facebook’s identity, popularity, and characteristics are shaped in important ways by its becoming a form of mobile media, as much as it as platform associated with Internet and social media. This paper seeks to explore and understand Facebook as the important force in mobile media and communication it now is. It draws upon and combines perspectives from technology production, design, and economy, as well as user adoption, consumption, practices, affect, emotion, and resistance. The paper discusses the beginnings of mobile Facebook, and the early adoption of mobile Facebook associated with the rise of smartphones. The second part of the paper explores Facebook’s integration with photography (with Instagram) and social games (such as Zynga’s Farmville). The paper argues that Facebook’s mobile career is an accomplishment that has distinctively melded evolving affordances, everyday use across a wide range of settings, as well as political economies, corporate strategy, and design.Australian Research Counci
Vibrational Spectroscopic Investigation of Molecular Crystals of Methylmercury(II) Halides
A nearly full assignment of the vibrational modes of methylmercury halide crystals has been proposed. Factor group analysis has been used to derive the vibrational selection rules for the lattice modes. It is concluded that the D2hU structure with four molecules in the unit cell. Lattice modes for CH.-sHgl and CD.-jHgl can be assigned on the basis of C2hU substructure with two molecules per unit cell.
The bromide gave an ultra-low wavenumber band (7.0 cm-1) which we were unable to assign. Force constants have been calculated on the basis of a primitive unit cell (containig two molecules). The internal HgX stretching force constants 2.112, 1.658, 1.507 and 1.347 N cm-1 and the transverse translatory force constants 0.719, 0.364, 0.266 and 0.218 N cm-1 obtained for fluoride, chloride, bromide, and iodide, respectively, show strong dependence on the kind of halide
A burst search for gravitational waves from binary black holes
Compact binary coalescence (CBC) is one of the most promising sources of
gravitational waves. These sources are usually searched for with matched
filters which require accurate calculation of the GW waveforms and generation
of large template banks. We present a complementary search technique based on
algorithms used in un-modeled searches. Initially designed for detection of
un-modeled bursts, which can span a very large set of waveform morphologies,
the search algorithm presented here is constrained for targeted detection of
the smaller subset of CBC signals. The constraint is based on the assumption of
elliptical polarisation for signals received at the detector. We expect that
the algorithm is sensitive to CBC signals in a wide range of masses, mass
ratios, and spin parameters. In preparation for the analysis of data from the
fifth LIGO-Virgo science run (S5), we performed preliminary studies of the
algorithm on test data. We present the sensitivity of the search to different
types of simulated CBC waveforms. Also, we discuss how to extend the results of
the test run into a search over all of the current LIGO-Virgo data set.Comment: 12 pages, 4 figures, 2 tables, submitted for publication in CQG in
the special issue for the conference proceedings of GWDAW13; corrected some
typos, addressed some minor reviewer comments one section restructured and
references updated and correcte
Pharmacological strategies to reduce anthracycline-associated cardiotoxicity in cancer patients.
INTRODUCTION: Anthracycline chemotherapeutic agents are widely used in the treatment of hematological and solid tumors, working principally through DNA intercalation and topoisomerase II inhibition. However, they are also well known to have cardiotoxic sequelae, commonly denoted as a reduction in ejection fraction. Drug-associated cardiotoxicity remains a significant limiting factor in the use of anthracyclines. AREAS COVERED: In this review, we explore the potential mechanisms of anthracycline-associated cardiotoxicity, identifying high-risk cohorts and approaches to cardiovascular monitoring. The mechanisms through which cardiotoxicity occurs are complex and diverse, ultimately leading to increased oxidative stress, mitochondrial dysfunction, and subsequent cellular apoptosis. Many of the cardiotoxic effects of anthracyclines exhibit a dose-dependent cumulative relationship and are more apparent in patients with previously existing cardiovascular risk factors. Long-term cardiovascular monitoring and optimization of risk factors, prior to commencing treatment as well as beyond the time of treatment, is therefore essential. EXPERT OPINION: We discuss some of the pharmacological strategies proposed to mitigate anthracycline-associated cardiotoxicity as well as prevention strategies to reduce the burden of coexisting cardiovascular risk factors. We highlight methods of early detection of patient cohorts who are at increased risk of developing anthracycline-associated cardiotoxicity and identify potential avenues for further research
Advance care planning in cystic fibrosis: Current practices, challenges, and opportunities
AbstractBackgroundStudies in cystic fibrosis (CF) report late attention to advance care planning (ACP). The purpose of this study was to examine ACP with patients receiving care at US adult CF care programs.MethodsChart abstraction was used to examine ACP with adults with CF dying from respiratory failure between 2011 and 2013.ResultsWe reviewed 210 deaths among 67 CF care programs. Median age at death was 29years (range 18–73). Median FEV1 in the year preceding death was 33% predicted (range 13–100%); 68% had severe lung disease with FEV1p=pp=0.55). The frequency of ACP varied significantly among the 29 programs contributing data from four or more deaths.ConclusionsACP in CF often occurs late in the disease course. Important decisions default to surrogates when opportunities for ACP are missed. Provision of ACP varies significantly among adult CF care programs. Careful evaluation of opportunities to enhance ACP and implementation of recommended approaches may lead to better practices in this important aspect of CF care
Environment-induced dynamical chaos
We examine the interplay of nonlinearity of a dynamical system and thermal
fluctuation of its environment in the ``physical limit'' of small damping and
slow diffusion in a semiclassical context and show that the trajectories of
c-number variables exhibit dynamical chaos due to the thermal fluctuations of
the bath.Comment: Revtex, 4 pages and 4 figure
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