37 research outputs found

    Photon and Graviton Mass Limits

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    Efforts to place limits on deviations from canonical formulations of electromagnetism and gravity have probed length scales increasing dramatically over time.Historically, these studies have passed through three stages: (1) Testing the power in the inverse-square laws of Newton and Coulomb, (2) Seeking a nonzero value for the rest mass of photon or graviton, (3) Considering more degrees of freedom, allowing mass while preserving explicit gauge or general-coordinate invariance. Since our previous review the lower limit on the photon Compton wavelength has improved by four orders of magnitude, to about one astronomical unit, and rapid current progress in astronomy makes further advance likely. For gravity there have been vigorous debates about even the concept of graviton rest mass. Meanwhile there are striking observations of astronomical motions that do not fit Einstein gravity with visible sources. "Cold dark matter" (slow, invisible classical particles) fits well at large scales. "Modified Newtonian dynamics" provides the best phenomenology at galactic scales. Satisfying this phenomenology is a requirement if dark matter, perhaps as invisible classical fields, could be correct here too. "Dark energy" {\it might} be explained by a graviton-mass-like effect, with associated Compton wavelength comparable to the radius of the visible universe. We summarize significant mass limits in a table.Comment: 42 pages Revtex4. This version contains corrections and changes contained in the published version, Rev. Mod. Phys. 82, 939-979 (2010), with a few addition

    Third universal definition of myocardial infarction

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    "Myocardial infarction (MI) can be recognised by clinical features, including electrocardiographic (ECG) findings, elevated values of biochemical markers (biomarkers) of myocardial necrosis, and by imaging, or may be defined by pathology. It is a major cause of death and disability worldwide. MI may be the first manifestation of coronary artery disease (CAD) or it may occur, repeatedly, in patients with established disease. Information on MI rates can provide useful information regarding the burden of CAD within and across populations, especially if standardized data are collected in a manner that distinguishes between incident and recurrent events. From the epidemiological point of view, the incidence of MI in a population can be used as a proxy for the prevalence of CAD in that population. The term ‘myocardial infarction’ may have major psychological and legal implications for the individual and society. It is an indicator of one of the leading health problems in the world and it is an outcome measure in clinical trials, observational studies and quality assurance programmes. These studies and programmes require a precise and consistent definition of MI. In the past, a general consensus existed for the clinical syndrome designated as MI. In studies of disease prevalence, the World Health Organization (WHO) defined MI from symptoms, ECG abnormalities and cardiac enzymes. However, the development of ever more sensitive and myocardial tissue-specific cardiac biomarkers and more sensitive imaging techniques now allows for detection of very small amounts of myocardial injury or necrosis. Additionally, the management of patients with MI has significantly improved, resulting in less myocardial injury and necrosis, in spite of a similar clinical presentation. Moreover, it appears necessary to distinguish the various conditions which may cause MI, such as ‘spontaneous’ and ‘procedure-related’ MI. Accordingly, physicians, other healthcare providers and patients require an up-to-date definition of MI.

    Third universal definition of myocardial infarction

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    "Myocardial infarction (MI) can be recognised by clinical features, including electrocardiographic (ECG) findings, elevated values of biochemical markers (biomarkers) of myocardial necrosis, and by imaging, or may be defined by pathology. It is a major cause of death and disability worldwide. MI may be the first manifestation of coronary artery disease (CAD) or it may occur, repeatedly, in patients with established disease. Information on MI rates can provide useful information regarding the burden of CAD within and across populations, especially if standardized data are collected in a manner that distinguishes between incident and recurrent events. From the epidemiological point of view, the incidence of MI in a population can be used as a proxy for the prevalence of CAD in that population. The term ‘myocardial infarction’ may have major psychological and legal implications for the individual and society. It is an indicator of one of the leading health problems in the world and it is an outcome measure in clinical trials, observational studies and quality assurance programmes. These studies and programmes require a precise and consistent definition of MI. In the past, a general consensus existed for the clinical syndrome designated as MI. In studies of disease prevalence, the World Health Organization (WHO) defined MI from symptoms, ECG abnormalities and cardiac enzymes. However, the development of ever more sensitive and myocardial tissue-specific cardiac biomarkers and more sensitive imaging techniques now allows for detection of very small amounts of myocardial injury or necrosis. Additionally, the management of patients with MI has significantly improved, resulting in less myocardial injury and necrosis, in spite of a similar clinical presentation. Moreover, it appears necessary to distinguish the various conditions which may cause MI, such as ‘spontaneous’ and ‘procedure-related’ MI. Accordingly, physicians, other healthcare providers and patients require an up-to-date definition of MI.

    Notes on the visitation of Lincolnshire, 1634.

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    The original is in the College of Arms, and no complete copy is known to exist outside the College."The visitation ... was made ... by Chitting, Chester herald, and Thompson, acting as deputies to St. George, Clarenceux, and Burroughs, Norroy."--Pref.Issued in parts, 1890-98.Mode of access: Internet

    The manuscripts of Lincoln, Bury St. Edmund's, and Great Grimsby corporation; and of the deans and chapters of Worcester and Lichfield, &c. ...

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    Prepared by W. D. Macray, W. J. Hardy, R. L. Poole and A. W. Gibbons.Parliament. Papers by command. C. 7881.At head of title: Historical manuscripts commission.Lincoln corporation.--Bury St. Edmund's corporation.--Hertford corporation.--The dean and chapter of Worcester.--The bishop's registry at Worcester.--The dean and chapter of Lichfield.--Great Grimsby corporation.Mode of access: Internet
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