58,460 research outputs found
Recession and Umemployment in the OECD
Konjunkturelle Arbeitslosigkeit; ErwerbstÀtigkeit; Arbeitsmarktpolitik; LebensqualitÀt; OECD-Staaten
Towards structured, block-based PDF
The Portable Document Format (PDF), defined by Adobe Systems Inc. as the basis of its Acrobat product range, is discussed in some detail. Particular emphasis is given to its flexible object-oriented structure, which has yet to be fully exploited. It is currently used to represent not logical structure but simply a series of pages and associated resources. A definition of an Encapsulated PDF (EPDF) is presented, in which EPDF blocks carry with them their own resource requirements, together with geometrical and logical information. A block formatter called Juggler is described which can lay out EPDF blocks from various sources onto new pages. Future revisions of PDF supporting uniquely-named EPDF blocks tagged with semantic information would assist in composite-pagemakeup and could even lead to fully revisable PDF
Debates in allergy medicine: Specific immunotherapy in children with atopic dermatitis, the "con" view.
Atopic dermatitis (AD) is a common chronic skin condition in children that has a proven association with other atopic conditions and allergies. These associations, like the general pathophysiology of AD, are complex and not fully understood. While there is evidence for the efficacy of specific immunotherapy (SIT) in pediatric asthma and allergic rhinitis (AR), there is a lack of strong data to support its use in AD. IgE has been shown to be elevated in many patients with AD, but it is an unreliable biomarker due to variability and great fluctuation over time, poor positive predictive value for clinically relevant allergy, and poor correlation with disease state. In spite of this, almost all studies of SIT use either positive skin prick testing (SPT) or serum specific IgE levels to guide therapy. Allergen avoidance, with some exceptions, is generally not effective at controlling AD in children. The few studies that have investigated the efficacy of SIT in children with AD have produced conflicting results, and a lack of reproducibility with a standard treatment protocol. Limited studies have shown clinical improvement in mild to moderate AD cases, but no effect on more severe patients. Uncontrolled studies are difficult to interpret, due to the natural history of remission or "outgrowing" of AD over time in many patients without specific interventions. Drawbacks to SIT include the length of treatment, poor compliance, cost, and potential side effect profile. The potential for misdirection of time and energy away from skin directed therapy could negatively impact on AD outcomes
The Impact of College Athletics on Employment in the Restaurant and Accommodations Industries
In this paper, we analyze Metropolitan and Micropolitan Statistical Area (MSA)-level data in the U.S. to examine the economic impact of college athletics. Specifically, we examine the relationship between total athletics revenues (aggregated across all colleges in an MSA) and MSA-level employment in the accommodations and food services industries. Controlling for a variety of other factors that might influence hotel/restaurant employment within an MSA, we find that below 40 million we find highly significant impacts on employment in the food services and accommodations industries that climb with college sports revenue generation.sports, college athletics, economic impact, food services and accommodations, tourism
The Economics of Vouchers
This paper aims to provide a swift tour of the economic issues presented by vouchers and thus to fill an apparent gap in the literature for a basic survey of the subject. Among the issues it considers are: factors determining a voucher's cash-equivalence; reasons (such as paternalism, externalities, and distribution) for giving beneficiaries non-cash-equivalent vouchers rather than cash; optimal tax issues involved in the design of vouchers and the choice between vouchers and other delivery mechanisms, including factors determining the optimal marginal reimbursement rate (MRR) in a voucher program, and the similarity between this question and that of determining optimal marginal tax rates (MTRs) under the income tax; the incentive effects of voucher eligibility criteria, such as income or asset tests; factors determining the allocative and price effects of vouchers, both in the short run when unexpectedly enacted and at equilibrium; and factors relevant to the choice between private and public supply that may often overlap with the decision whether to adopt a voucher program.
Recommended from our members
Life After Being a Pathology Department Chair: Issues and Opportunities.
Although there is a considerable literature on transition of faculty members to the position of department chair, there is a dearth of publications about transitioning from the chair to other activities including retirement. The Association of Pathology Chairs senior fellows (all of whom are former chairs of academic departments of pathology) made this topic a focus of discussion at the Association of Pathology Chairs 2016 Annual Meeting. Of the 33 senior fellows engaged in this discussion, following their time as chairs, a small majority (18) transitioned to other administrative posts within or outside the university, while the others either returned to the active faculty (7) or retired (8). The motivating factors and influences for transitioning from the chair were probed along with the processes used in executing the transition, such as the development of transition plans. The reasons for selecting the specific type of postchair activity were also investigated. There was extraordinary diversity in the type of post-chair activities pursued. To our knowledge, no other medical specialty has examined these issues, which may be potentially relevant for the career planning of active chairs
Recommended from our members
Life After Being a Pathology Department Chair II: Lessons Learned.
The 2016 Association of Pathology Chairs annual meeting featured a discussion group of Association of Pathology Chairs senior fellows (former chairs of academic departments of pathology who have remained active in Association of Pathology Chairs) that focused on how they decided to transition from the chair, how they prepared for such transition, and what they did after the transition. At the 2017 annual meeting, the senior fellows (encompassing 481 years of chair service) discussed lessons they learned from service as chair. These lessons included preparation for the chairship, what they would have done differently as chair, critical factors for success as chair, factors associated with failures, stress reduction techniques for themselves and for their faculty and staff, mechanisms for dealing with and avoiding problems, and the satisfaction they derived from their service as chair. It is reasonable to assume that these lessons may be representative of those learned by chairs of other specialties as well as by higher-level academic administrators such as deans, vice presidents, and chief executive officers. Although the environment for serving as a department chair has been changing dramatically, many of the lessons learned by former chairs are still valuable for current chairs of any length of tenure
Cohomology for Anyone
Crystallography has proven a rich source of ideas over several centuries.
Among the many ways of looking at space groups, N. David Mermin has pioneered
the Fourier-space approach. Recently, we have supplemented this approach with
methods borrowed from algebraic topology. We now show what topology, which
studies global properties of manifolds, has to do with crystallography. No
mathematics is assumed beyond what the typical physics or crystallography
student will have seen of group theory; in particular, the reader need not have
any prior exposure to topology or to cohomology of groups.Comment: 21 pages + figures, bibliography, Mathematica code homology.
Sequential item pricing for unlimited supply
We investigate the extent to which price updates can increase the revenue of
a seller with little prior information on demand. We study prior-free revenue
maximization for a seller with unlimited supply of n item types facing m myopic
buyers present for k < log n days. For the static (k = 1) case, Balcan et al.
[2] show that one random item price (the same on each item) yields revenue
within a \Theta(log m + log n) factor of optimum and this factor is tight. We
define the hereditary maximizers property of buyer valuations (satisfied by any
multi-unit or gross substitutes valuation) that is sufficient for a significant
improvement of the approximation factor in the dynamic (k > 1) setting. Our
main result is a non-increasing, randomized, schedule of k equal item prices
with expected revenue within a O((log m + log n) / k) factor of optimum for
private valuations with hereditary maximizers. This factor is almost tight: we
show that any pricing scheme over k days has a revenue approximation factor of
at least (log m + log n) / (3k). We obtain analogous matching lower and upper
bounds of \Theta((log n) / k) if all valuations have the same maximum. We
expect our upper bound technique to be of broader interest; for example, it can
significantly improve the result of Akhlaghpour et al. [1]. We also initiate
the study of revenue maximization given allocative externalities (i.e.
influences) between buyers with combinatorial valuations. We provide a rather
general model of positive influence of others' ownership of items on a buyer's
valuation. For affine, submodular externalities and valuations with hereditary
maximizers we present an influence-and-exploit (Hartline et al. [13]) marketing
strategy based on our algorithm for private valuations. This strategy preserves
our approximation factor, despite an affine increase (due to externalities) in
the optimum revenue.Comment: 18 pages, 1 figur
Isoprene Emission and Carbon Dioxide Protect Aspen Leaves from Heat Stress
High temperature, especially above 35oC, is known to reduce leaf photosynthetic rate in many tree species. This study investigated the effect of high temperature on isoprene-emitting (aspen) and non- emitting (birch) trees under ambient and elevated CO2 under open field conditions. Aspen trees tolerate heat better than birch trees and elevated CO2 protects both species against moderate heat stress. The increased thermotolerance in aspen trees compared to the birch trees may result from the aspen's ability to produce isoprene. Elevated CO2 increased carboxylation capacity, photosynthetic electron transport capacity and triose phosphate use in both birch and aspen trees. High temperature decreased all of these parameters in birch regardless of CO2 treatment but only photosynthetic electron transport and triose phosphate use at ambient CO2 were reduced in aspen. As temperature rises, non-isoprene-emitting trees will be at a disadvantage and biological diversity and species richness might be lost in some ecosystems. Our results indicate that isoprene emitting tree species will have an advantage over non-isoprene emitting ones under high temperatures
- âŠ