Exotic smooth structures on 4-manifolds with zero signature

For every integer $k\geq 2$, we construct infinite families of mutually nondiffeomorphic irreducible smooth structures on the topological $4$-manifolds $(2k-1)(S^2\times S^2)$ and (2k-1)(\CP#\CPb), the connected sums of $2k-1$ copies of $S^2\times S^2$ and \CP#\CPb.Comment: 6 page

What's wrong with the scrum laws in rugby union? - Judgment, truth and refereeing

Officiating and the role of officials in sport are crucial and often decisive factors in sports contests. Notable contributions in philosophy of sport include Collins (2012), Russell (1997; 1999), McFee (2011) & Mumford (2006) have brought a sharp philosophical focus to highlight that justice and desert of sport contests, in part, rely on officiating truths (performances) that arise from an appropriate admixture of epistemic (judgments) and metaphysical (actions) ingredients. This paper provides a rigorous and original philosophical analysis of the problems of obeying the rules and of applying the rules of sport. The paper focuses on a particular phase of play in rugby union, namely the scrum. It is fair to say that the scrum has become a focus of criticism and bewilderment. Elite televised rugby is damaged as a spectacle because too much time is wasted setting and re-setting scrums. Furthermore, our trust in the fairness of games is eroded because the scrum is a ‘lottery’ when it comes to officiating. In this paper, we identify two fundamental structural problems which contribute to the scrum controversy. First, drawing on Mumford (2006) and Collins (2012) we argue that officials cannot make reliable judgments about scrums because they cannot see what they need to see. Secondly, we argue that players cannot follow the laws of the scrum even if they have a strong desire to do so. Laws which can’t be followed are, according to Fuller (2000) defective. Consequently, the scrum is not only potentially dangerous but also flawed in terms of its capacity to actualize an intended part of the game

Detection of a supervoid aligned with the cold spot of the cosmic microwave background

We use the WISE-2MASS infrared galaxy catalogue matched with Pan-STARRS1 (PS1) galaxies to search for a supervoid in the direction of the cosmic microwave background (CMB) cold spot (CS). Our imaging catalogue has median redshift z ≃ 0.14, and we obtain photometric redshifts from PS1 optical colours to create a tomographic map of the galaxy distribution. The radial profile centred on the CS shows a large low-density region, extending over tens of degrees. Motivated by previous CMB results, we test for underdensities within two angular radii, 5°, and 15°. The counts in photometric redshift bins show significantly low densities at high detection significance, ≳5σ and ≳6σ, respectively, for the two fiducial radii. The line-of-sight position of the deepest region of the void is z ≃ 0.15–0.25. Our data, combined with an earlier measurement by Granett, Szapudi & Neyrinck, are consistent with a large Rvoid = (220 ± 50) h−1 Mpc supervoid with δm ≃ −0.14 ± 0.04 centred at z = 0.22 ± 0.03. Such a supervoid, constituting at least a ≃3.3σ fluctuation in a Gaussian distribution of the Λ cold dark matter model, is a plausible cause for the CS

The Use of the S-Quattro Dynamic External Fixator for the Treatment of Intra-Articular Phalangeal Fractures: A Review of the Literature

Intra-articular phalangeal fractures are a common injury. If left untreated, these injuries can lead to poor functional outcome with severe dehabilitating consequences, especially in younger patients

Standardized Outcome Measurement for Patients With Coronary Artery Disease: Consensus From the International Consortium for Health Outcomes Measurement (ICHOM)

Coronary artery disease (CAD) outcomes consistently improve when they are routinely measured and provided back to physicians and hospitals. The International Consortium for Health Outcomes Measurement (ICHOM) established a Working Group to define a standard set of outcome measures and risk factors of CAD care. Members were drawn from 4 continents and 6 countries. Using a modified Delphi method, the Group defined who should be tracked, what should be measured, and when such measurements should be performed. Thirteen specific outcomes were chosen, including acute complications occurring within 30 days of acute myocardial infarction, coronary artery bypass grafting surgery, or percutaneous coronary intervention; and longitudinal outcomes for up to 5 years for patient‐reported health status (Seattle Angina Questionnaire [SAQ‐7], elements of Rose Dyspnea Score, and Patient Health Questionnaire [PHQ‐2]), cardiovascular hospital admissions, cardiovascular procedures, renal failure, and mortality. Baseline demographic, cardiovascular disease, and comorbidity information is included to improve the interpretability of comparisons

On the Relationship between Yang-Mills Theory and Gravity and its Implication for Ultraviolet Divergences

String theory implies that field theories containing gravity are in a certain sense `products' of gauge theories. We make this product structure explicit up to two loops for the relatively simple case of N=8 supergravity four-point amplitudes, demonstrating that they are `squares' of N=4 super-Yang-Mills amplitudes. This is accomplished by obtaining an explicit expression for the $D$-dimensional two-loop contribution to the four-particle S-matrix for N=8 supergravity, which we compare to the corresponding N=4 Yang-Mills result. From these expressions we also obtain the two-loop ultraviolet divergences in dimensions D=7 through D=11. The analysis relies on the unitarity cuts of the two theories, many of which can be recycled from a one-loop computation. The two-particle cuts, which may be iterated to all loop orders, suggest that squaring relations between the two theories exist at any loop order. The loop-momentum power-counting implied by our two-particle cut analysis indicates that in four dimensions the first four-point divergence in N=8 supergravity should appear at five loops, contrary to the earlier expectation, based on superspace arguments, of a three-loop counterterm.Comment: Latex, 52 pages, discussion of 2 loop divergences in D=8,10 adde

Influence of coding variability in APP-Aß metabolism genes in sporadic Alzheimer's disease

The cerebral deposition of Aß42, a neurotoxic proteolitic derivate of amyloid precursor protein (APP), is a central event in Alzheimer’s disease (AD)(Amyloid hypothesis). Given the key role of APP-Aß metabolism in AD pathogenesis, we selected 29 genes involved in APP processing, Aß degradation and clearance. We then used exome and genome sequencing to investigate the single independent (single-variant association test) and cumulative (gene-based association test) effect of coding variants in these genes as potential susceptibility factors for AD, in a cohort composed of 435 sporadic and mainly late-onset AD cases and 801 elderly controls from North America and the UK. Our study shows that common coding variability in these genes does not play a major role for the disease development. In the single-variant association analysis, the main hits, which were nominally significant, were found to be very rare coding variants (MAF 0.3%-0.8%) that map to genes involved in APP processing (MEP1B), trafficking and recycling (SORL1), Aß extracellular degradation (ACE) and clearance (LRP1). Moreover, four genes (ECE1, LYZ, TTR and MME) have been found as nominally associated to AD using c-alpha and SKAT tests. We suggest that Aβ degradation and clearance, rather than Aβ production, may play a crucial role in the etiology of sporadic AD