115 research outputs found
Federal Forest Restoration Program use of the Good Neighbor Authority : 2016-2021 activities and outcomes
2 pagesRestoration is a pressing need across Oregon’s forests—over 7 million acres are experiencing declining
forest health and are at elevated risk of large and destructive wildfires. Oregon Department of Forestry’s
(ODF) Federal Forest Restoration Program partners with federal agencies to restore and steward these
important lands to enhance and protect the valuable benefits they provide for Oregonians. ODF supports
three key elements of restoration: Planning – Implementation – Monitoring, all integral to restoring land in
an ecologically sound, scientific manner. This fact sheet summarizes the results of ODF’s efforts to increase
the pace, scale and quality of restoration on federal lands in Oregon.Funded by Oregon Department of Forestry
Quantum mechanical analysis of the equilateral triangle billiard: periodic orbit theory and wave packet revivals
Using the fact that the energy eigenstates of the equilateral triangle
infinite well (or billiard) are available in closed form, we examine the
connections between the energy eigenvalue spectrum and the classical closed
paths in this geometry, using both periodic orbit theory and the short-term
semi-classical behavior of wave packets. We also discuss wave packet revivals
and show that there are exact revivals, for all wave packets, at times given by
where and are the length of one side
and the mass of the point particle respectively. We find additional cases of
exact revivals with shorter revival times for zero-momentum wave packets
initially located at special symmetry points inside the billiard. Finally, we
discuss simple variations on the equilateral
() triangle, such as the half equilateral
() triangle and other `foldings', which have
related energy spectra and revival structures.Comment: 34 pages, 9 embedded .eps figure
The Role of Tobacco Smoke in Bladder and Kidney Carcinogenesis: A Comparison of Exposures and Meta-analysis of Incidence and Mortality Risks.
Context
Tobacco smoke includes a mix of carcinogens implicated in the etiology of bladder cancer (BC) and renal cell cancer (RCC).
Objective
We reviewed the impact of tobacco exposure on BCC and RCC incidence and mortality, and whether smoking cessation decreases the risk.
Evidence acquisition
A systematic review of original articles in English was performed in August 2013. Meta-analysis of risks was performed using adjusted risk ratios where available. Publication bias was assessed using Begg and Egger tests.
Evidence synthesis
We identified 2683 papers, of which 114 fulfilled our inclusion criteria, of which 90 studies investigated BC and 24 investigated RCC. The pooled relative risk (RR) of BC incidence was 2.57 (95% confidence interval [CI] 2.37–2.78) for all smokers, 3.37 (3.01–3.78) for current smokers, and 1.98 (1.76–2.22) for former smokers. The corresponding pooled RR of BC disease-specific mortality (DSM) was 1.79 (1.40–2.29), 1.89 (1.29–2.78) and 1.66 (1.10–2.52). The pooled RR of RCC incidence was 1.27 (1.18–135) for all smokers, 1.29 (1.14–1.46) for current smokers, and 1.14 (1.06–1.22) for former smokers. The corresponding RCC DSM risk was 1.20 (1.02–1.41), 1.32 (1.08–1.62), and 1.01 (0.85–1.18).
Conclusions
We present an up-to-date review of tobacco smoking and BC and RCC incidence and mortality. Tobacco smoking significantly increases the risk of BC and RCC incidence. BC incidence and DSM risk are greatest in current smokers and lowest in former smokers, indicating that smoking cessation confers benefit. We found that secondhand smoke exposure is associated with a significant increase in BC risk.
Patient summary
Tobacco smoking affects the development and progression of bladder cancer and renal cell cancer. Smoking cessation reduces the risks of developing and dying from these common cancers. We quantify these risks using the most up-to-date results published in the literature
A generalized Hamiltonian Constraint Operator in Loop Quantum Gravity and its simplest Euclidean Matrix Elements
We study a generalized version of the Hamiltonian constraint operator in
nonperturbative loop quantum gravity. The generalization is based on admitting
arbitrary irreducible SU(2) representations in the regularization of the
operator, in contrast to the original definition where only the fundamental
representation is taken. This leads to a quantization ambiguity and to a family
of operators with the same classical limit. We calculate the action of the
Euclidean part of the generalized Hamiltonian constraint on trivalent states,
using the graphical notation of Temperley-Lieb recoupling theory. We discuss
the relation between this generalization of the Hamiltonian constraint and
crossing symmetry.Comment: 35 pp, 20 eps figures; minor corrections, references added; version
to appear in Class. Quant. Gra
Timescales of Massive Human Entrainment
The past two decades have seen an upsurge of interest in the collective
behaviors of complex systems composed of many agents entrained to each other
and to external events. In this paper, we extend concepts of entrainment to the
dynamics of human collective attention. We conducted a detailed investigation
of the unfolding of human entrainment - as expressed by the content and
patterns of hundreds of thousands of messages on Twitter - during the 2012 US
presidential debates. By time locking these data sources, we quantify the
impact of the unfolding debate on human attention. We show that collective
social behavior covaries second-by-second to the interactional dynamics of the
debates: A candidate speaking induces rapid increases in mentions of his name
on social media and decreases in mentions of the other candidate. Moreover,
interruptions by an interlocutor increase the attention received. We also
highlight a distinct time scale for the impact of salient moments in the
debate: Mentions in social media start within 5-10 seconds after the moment;
peak at approximately one minute; and slowly decay in a consistent fashion
across well-known events during the debates. Finally, we show that public
attention after an initial burst slowly decays through the course of the
debates. Thus we demonstrate that large-scale human entrainment may hold across
a number of distinct scales, in an exquisitely time-locked fashion. The methods
and results pave the way for careful study of the dynamics and mechanisms of
large-scale human entrainment.Comment: 20 pages, 7 figures, 6 tables, 4 supplementary figures. 2nd version
revised according to peer reviewers' comments: more detailed explanation of
the methods, and grounding of the hypothese
Explore, Scale Up, Move Out: Three Phases to Managing Change under Conditions of Uncertainty
Private sector development is dominated by the use of ‘good practice’ solutions, driven by a desire of the development donors to control the outcome of development initiatives – with limited success. Bottom?up participatory approaches are more appropriate to find solutions for the complex challenge of market and private sector development. Theory?based approaches are used to design and deliver solutions to economic development challenges. We argue that these approaches have limited potential to manage interventions that target systemic change in complex contexts. On the other hand, alternative approaches based on emergence have some essential shortcomings from the perspective of the international development system. Based on our own working experience, we propose a pragmatic way forward that aims to build on the strengths of emergence?based approaches in complex contexts but is designed to work in the current development environment
Most Networks in Wagner's Model Are Cycling
In this paper we study a model of gene networks introduced by Andreas Wagner in the 1990s that has been used extensively to study the evolution of mutational robustness. We investigate a range of model features and parameters and evaluate the extent to which they influence the probability that a random gene network will produce a fixed point steady state expression pattern. There are many different types of models used in the literature, (discrete/continuous, sparse/dense, small/large network) and we attempt to put some order into this diversity, motivated by the fact that many properties are qualitatively the same in all the models. Our main result is that random networks in all models give rise to cyclic behavior more often than fixed points. And although periodic orbits seem to dominate network dynamics, they are usually considered unstable and not allowed to survive in previous evolutionary studies. Defining stability as the probability of fixed points, we show that the stability distribution of these networks is highly robust to changes in its parameters. We also find sparser networks to be more stable, which may help to explain why they seem to be favored by evolution. We have unified several disconnected previous studies of this class of models under the framework of stability, in a way that had not been systematically explored before
Beyond Gaussian Averages: Redirecting Management Research Toward Extreme Events and Power Laws
The James Webb Space Telescope Mission
Twenty-six years ago a small committee report, building on earlier studies,
expounded a compelling and poetic vision for the future of astronomy, calling
for an infrared-optimized space telescope with an aperture of at least .
With the support of their governments in the US, Europe, and Canada, 20,000
people realized that vision as the James Webb Space Telescope. A
generation of astronomers will celebrate their accomplishments for the life of
the mission, potentially as long as 20 years, and beyond. This report and the
scientific discoveries that follow are extended thank-you notes to the 20,000
team members. The telescope is working perfectly, with much better image
quality than expected. In this and accompanying papers, we give a brief
history, describe the observatory, outline its objectives and current observing
program, and discuss the inventions and people who made it possible. We cite
detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space
Telescope Overview, 29 pages, 4 figure
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