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A Late 20th Century European Climate Shift: Fingerprint of Regional Brightening?  [PDF]
A. T. J. de Laat, M. Crok
Atmospheric and Climate Sciences (ACS) , 2013, DOI: 10.4236/acs.2013.33031

We investigate the spatial extent of a statistically highly significant shift in atmospheric temperatures over Europe around 1987-1988 using a boot-strap change point algorithm. According to this algorithm, this change point (average warming of about one degree Celsius) is statistically highly significant (p > 99.9999%). The change point is consistently present in satellite and surface temperature measurements as well as temperature re-analyses and ocean heat content over most of Western Europe. We also find a connection with parts of the North Atlantic Ocean and eastern Asia. Although the time of change coincides with the North Atlantic Oscillation (NAO) going from negative to positive, the consistent warmer temperatures throughout the decades after 1987-1988 does not coincide with a persistent shift of the NAO, as it returns to a neutral/negative in the 1990’s. Furthermore, the shift does not coincide with any other known mode of multidecadal internal climate variability. We argue that the notion of a shift is “spurious”, i.e. the result of a fast change in Europe from dimming to brightening combined with an accidental sequence of cold (negative NAO) and warm (positive) NAO years during this period. The “shift” could therefore be considered as a fingerprint of European brightening during the last few decades.

Gravity darkening and brightening in binaries  [PDF]
Helen E. White,Thomas W. Baumgarte,Stuart L. Shapiro
Physics , 2012, DOI: 10.1088/0004-637X/752/2/122
Abstract: We apply a von Zeipel gravity darkening model to corotating binaries to obtain a simple, analytical expression for the emergent radiative flux from a tidally distorted primary orbiting a point-mass secondary. We adopt a simple Roche model to determine the envelope structure of the primary, assumed massive and centrally condensed, and use the results to calculate the flux. As for single rotating stars, gravity darkening reduces the flux along the stellar equator of the primary, but, unlike for rotating stars, we find that gravity brightening enhances the flux in a region around the stellar poles. We identify a critical limiting separation beyond which hydrostatic equilibrium no longer is possible, whereby the flux vanishes at the point on the stellar equator of the primary facing the companion. For equal-mass binaries, the total luminosity is reduced by about 13 % when this limiting separation is reached.
Sequential Chomospheric Brightening: An Automated Approach to Extracting Physics from Ephemeral Brightening  [PDF]
Michael S. Kirk,K. S. Balasubramaniam,Jason Jackiewicz,R. T. James McAteer,Bernie J. McNamara
Physics , 2012,
Abstract: We make a comparison between small scale chromospheric brightenings and energy release processes through examining the temporal evolution of sequential chromospheric brightenings (SCBs), derive propagation velocities, and propose a connection of the small-scale features to solar flares. Our automated routine detects and distinguishes three separate types of brightening regularly observed in the chromosphere: plage, flare ribbon, and point brightenings. By studying their distinct dynamics, we separate out the flare-associated bright points commonly known as SCBs and identify a propagating Moreton wave. Superimposing our detections on complementary off-band images, we extract a Doppler velocity measurement beneath the point brightening locations. Using these dynamic measurements, we put forward a connection between point brightenings, the erupting flare, and overarching magnetic loops. A destabilization of the pre-flare loop topology by the erupting flare directly leads to the SCBs observed.
The controversial pen of Edwin Holmes  [PDF]
Jeremy Shears
Physics , 2014,
Abstract: Edwin Alfred Holmes (1839 -1919) is best remembered for his discovery of a bright comet in 1892, now known as Comet 17P/Holmes. An amateur astronomer and authority on optics, he was an original member of the BAA and contributed to its Journal and meetings for many years. As a prolific writer of letters to the English Mechanic, he developed a reputation for his controversial and acerbic penmanship.
Controversial reversal of nuclear option
Mesarovi? Miodrag
Nuclear Technology and Radiation Protection , 2002, DOI: 10.2298/ntrp0202050m
Abstract: Nuclear option is in a unique position to restore its original role of the main source of energy with an increased attention paid to the security of electricity supply as well as regulatory changes affecting fossil fuels, particularly with due introduction of climate change prevention measures. Recent developments indicate the advantages of nuclear option over other possible options in terms of sustainable development. However, a large number of controversial issues on nuclear energy make its reversal less clear. These are discussed with particular attention paid to recent developments worldwide, including the World Summit on Sustainable Development held in September 2002 in Johannesburg, South Africa.
Kotrannavar Vijaykumar S.
International Journal of Research in Ayurveda and Pharmacy , 2012,
Abstract: In Rasashastra one can come across certain controversies regarding the identification of Rasashastra dravyas namely Chapala, Vimala, Vaikranta, Agnijara, Kampillaka and Kankustha.Kankustha, one of the controversial drugs, is classified under Uparasa. Different opinions are given about this drug. Dalhana says that this is the exudates of SwarnaKshiri (Argemon mexicana). According to Baluki, this is an ore of Vanga (Tin), Rasavagbhata opines that this is the meconium of the newborn Elephant and according to some Acharyas this is the Umbilical cord of the new born Horse. In Ayurveda it is used for Vrana, Udavarta, Arsha, Amavata and Jalodhara. In this paper, controversies about Kankustha, collection, different synonyms, varieties, shodhana procedure, dose, anupana, indications and different Yogas containing Kankustha has been discussed.
Handling controversial arguments by matrix  [PDF]
Xu Yuming
Computer Science , 2011,
Abstract: We introduce matrix and its block to the Dung's theory of argumentation framework. It is showed that each argumentation framework has a matrix representation, and the indirect attack relation and indirect defence relation can be characterized by computing the matrix. This provide a powerful mathematics way to determine the "controversial arguments" in an argumentation framework. Also, we introduce several kinds of blocks based on the matrix, and various prudent semantics of argumentation frameworks can all be determined by computing and comparing the matrices and their blocks which we have defined. In contrast with traditional method of directed graph, the matrix method has an excellent advantage: computability(even can be realized on computer easily). So, there is an intensive perspective to import the theory of matrix to the research of argumentation frameworks and its related areas.
Longitudinal development of a substorm brightening arc
Annales Geophysicae (ANGEO) , 2009,
Abstract: We present simultaneous THEMIS-ground observations of longitudinal (eastward) extension of a substorm initial-brightening arc at Gillam (magnetic latitude: 65.6°) at 08:13 UT on 10 January 2008. The speed of the eastward arc extension was ~2.7 km/s. The extension took place very close to the footprints of the longitudinally separated THEMIS E and D satellites at ~12 RE. The THEMIS satellites observed field dipolarization, weak earthward flow, and pressure increase, which propagated eastward from E to D at a speed of ~50 km/s. The THEMIS A satellite, located at 1.6 RE earthward of THEMIS E, observed fluctuating magnetic field during and after the dipolarization. The THEMIS E/D observations suggest that the longitudinal extension of the brightening arc at substorm onset is caused by earthward flow braking processes which produce field dipolarization and pressure increase propagating in longitude in the near-earth plasma sheet.
Imprecise k-space sampling and central brightening  [PDF]
R. A. Hanel,S. De Backer,J. Sijbers,P. Scheunders
Physics , 2006,
Abstract: In real-world sampling of k-space data, one generally makes a stochastic error not only in the value of the sample but in the effective position of the drawn sample. We refer to the latter as imprecise sampling and apply this concept to the fourier-based acquisition of magnetic resonance data. The analysis shows that the effect of such imprecisely sampled data accounts for contributions to noise, blurring, and intensity-bias in the image. Under general circumstances, the blur and the bias may depend on the scanned specimen itself. We show that for gaussian distributed imprecision of k-vector samples the resulting intensity inhomogeneity can be explicitly computed. The presented mechanism of imprecise k-space sampling (IKS) provides a complementary explanation for the phenomenon of central brightening in high-field magnetic resonance imaging. In computed experiments, we demonstrate the adequacy of the IKS effect for explaining central brightening. Furthermore, the experiments show that basic properties of IKS can in principle be inferred from real MRI data by the analysis on the basis of bias fields in magnitude images and information contained in the phase-images.
Publication of Controversial Papers in Life  [PDF]
Shu-Kun Lin
Life , 2012, DOI: 10.3390/life2010213
Abstract: Life (ISSN 2075-1729, http://www.mdpi.com/journal/life/) is a new journal that deals with new and sometime difficult interdisciplinary matters. Consequently, the journal will occasionally be presented with submitted articles that are controversial and/or outside conventional scientific views. Some papers recently accepted for publication in Life have attracted significant attention. Moreover, members of the Editorial Board have objected to these papers; some have resigned, and others have questioned the scientific validity of the contributions. In response I want to first state some basic facts regarding all publications in this journal. All papers are peer-reviewed, although it is often difficult to obtain expert reviewers for some of the interdisciplinary topics covered by this journal. I feel obliged to stress that although we will strive to guarantee the scientific standard of the papers published in this journal, all the responsibility for the ideas contained in the published articles rests entirely on their authors. Discussions on previously published articles are welcome and I hope that, by fostering discussion and by keeping an open-minded attitude towards new ideas, the journal will spur progress in this little explored, difficult and very exciting area of knowledge. [...]
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