8,287 research outputs found
Source Mergers and Bubble Growth During Reionization
The recently introduced models of reionization bubbles based on extended
Press-Schechter theory (Furlanetto, Zaldarriaga & Hernquist 2004) are
generalized to include mergers of ionization sources. Sources with a recent
major merger are taken to have enhanced photon production due to star
formation, and accretion onto a central black hole if a black hole is present.
This produces a scatter in the number of ionized photons corresponding to a
halo of a given mass and a change in photon production over time for any given
halo mass. Photon production histories, bubble distributions, and ionization
histories are computed for several different parameter and recombination
assumptions; the resulting distributions interpolate between previously
calculated limiting cases.Comment: 44 pages, 11 figures, version to appear in MNRAS. Some discussion of
case with WMAP parameters and expanded explanation
China Since Tiananmen: The Labor Movement
[Excerpt] The twenty years since 1989 have brought two major developments in worker activism. First, whereas workers were part of the mass uprising in the Tiananmen movement, albeit as subordinate partners to the students, labor activism since then has been almost entirely confined to the working class. While the ranks of aggrieved workers have proliferated (expanding from workers in the state-owned sector to include migrant workers) and the forms and incidents of labor activism have multiplied, there is hardly any sign of mobilization that transcends class or regional lines.
Second, we observe that a long-term decline in worker power at the point of production – power that was previously institutionalized in skill hierarchies, union representation, democratic management, permanent or long-term employment, and other conditions of service constitutive of the socialist social contract - is going on even as workers gain more power (at least on paper) outside the workplace. New labor laws have broadened workers\u27 rights and expanded administrative and judicial channels for resolving labor conflicts. These legal and bureaucratic procedures have atomized and depoliticized labor activism even as they have engendered and intensified mobilization outside official limits
Algorithm Instance Games
This paper introduces algorithm instance games (AIGs) as a conceptual
classification applying to games in which outcomes are resolved from joint
strategies algorithmically. For such games, a fundamental question asks: How do
the details of the algorithm's description influence agents' strategic
behavior?
We analyze two versions of an AIG based on the set-cover optimization
problem. In these games, joint strategies correspond to instances of the
set-cover problem, with each subset (of a given universe of elements)
representing the strategy of a single agent. Outcomes are covers computed from
the joint strategies by a set-cover algorithm. In one variant of this game,
outcomes are computed by a deterministic greedy algorithm, and the other
variant utilizes a non-deterministic form of the greedy algorithm. We
characterize Nash equilibrium strategies for both versions of the game, finding
that agents' strategies can vary considerably between the two settings. In
particular, we find that the version of the game based on the deterministic
algorithm only admits Nash equilibrium in which agents choose strategies (i.e.,
subsets) containing at most one element, with no two agents picking the same
element. On the other hand, in the version of the game based on the
non-deterministic algorithm, Nash equilibrium strategies can include agents
with zero, one, or every element, and the same element can appear in the
strategies of multiple agents.Comment: 14 page
Economic Analysis of Sequestering Carbon in Green Ash Forests in the Lower Mississippi River Valley
Since the U.S. is the largest emitter of carbon dioxide (CO2), it has become crucial to develop options that are both cost effective and supportive of sustainable development to reduce atmospheric CO2. Electric utility companies have the options of reducing their use of fossil fuels, switching to alternative energy sources, increasing efficiency, or offsetting carbon emissions. This study determined the cost and profitability of sequestering carbon in green ash plantations, and the number of tons of carbon that can be sequestered. The profitability of green ash is 3,645 per acre on site indices (measurement of soil quality) 65 and 105 land, respectively, calculated with a 2.5% alternative rate of return (ARR). These figures shift to –240 calculated with a 15.0% ARR. If landowners who have an ARR of 2.5% can sell carbon credits for 107 per acre on poor sites and 15.20 per ton on poor sites to 8.51 per ton on poor sites to $7.63 on good sites, calculated with a 15.0% ARR. The cost of storing carbon can be reduced significantly if the trees can be sold for wood products
MODIFYING A ONE REGION LEONTIEF INPUT-OUTPUT MODEL TO SHOW SECTOR CAPACITY CONSTRAINTS
A one-region Leontief input-output model may be modified to show sector capacity constraints or 'sector destruction.' The economist must know the degree of sector destruction, level of imports of the destroyed sector's product, and make certain assumptions about the regional economy. Six cases are presented based on the degree of destruction (complete or partial) and level of imports of the destroyed sector's product (none, sufficient to reach original final demands or insufficient to reach original final demands). A linear programming version of the input-output model is suggested for three of the six cases.Research Methods/ Statistical Methods,
Early Delirium Assessment for Hospitalized Older People in Indonesia: a Systematic Review
Background: Due to the increasing risk of getting co-morbidity and frailty, older people tend to be prone to hospitalization. Hospitalization in older people brings many adverse effects. Moreover, when these elderly get delirium, the mortality and morbidity will increase. The risk of getting deterioration and worsening condition because of delirium would also increase. In fact, delirium assessment is not a high priority in taking care older people during hospitalization because the focus of care is treating the disease.Delirium screening as an early recognition of delirium in the hospitalized elderly inIndonesia remains unreported and even do not well evaluated. Therefore, delirium as a preventable problem or causing problems remains unrecognized.Purpose: This paper aims to review the current evidence of early assessment of delirium in hospitalized older people.Methods: A systematic review was conducted from four databases yielding to 4 articles which met the inclusion and exclusion criteria.Results: There are four focuses on the result, namely delirium screening tools, patient characteristics, identified early delirium assessment, and outcomes affected by early delirium assessment. Confusion Assessment Method (CAM) was used as the delirium screening tool in the hospital. Establishing the care team involving many disciplines will give a better way to improve the integrated care and collaborative care.Conclusion: Performing CAM integrated into comprehensive geriatric assessment can be the most important thing to be undertaken when looking after the hospitalized elderly
Physiological Electrical Signals Promote Chain Migration of Neuroblasts by Up-Regulating P2Y1 Purinergic Receptors and Enhancing Cell Adhesion
Acknowledgments This work was supported by a grant from NHS Grampian. Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are creditedPeer reviewedPublisher PD
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