Michael Pärt ئ suure muusika taustajõud / Michael Pärt ; interv. Siim Nestor

Index Scriptorium Estoniae

Pärt, Michael

2008-01-01

Arvo Pärdi pojast Michael Pärdist. Tema tööst "music editor"-ina - helimonteerijana, tööst muusika produktsiooni, salvestamise ja muusika kirjutamise abijõuna. Koostööst maailmas tuntud muusikutega

Chiral Aminophosphines as Catalysts for Enantioselective Double-Michael Indoline Syntheses

Directory of Open Access Journals (Sweden)

Ohyun Kwon

2012-05-01

Full Text Available The bisphosphine-catalyzed double-Michael addition of dinucleophiles to electron-deficient acetylenes is an efficient process for the synthesis of many nitrogen-containing heterocycles. Because the resulting heterocycles contain at least one stereogenic center, this double-Michael reaction would be even more useful if an asymmetric variant of the reaction were to be developed. Aminophosphines can also facilitate the double-Michael reaction and chiral amines are more readily available in Nature and synthetically; therefore, in this study we prepared several new chiral aminophosphines. When employed in the asymmetric double-Michael reaction between ortho-tosylamidophenyl malonate and 3-butyn-2-one, the chiral aminophosphines produced indolines in excellent yields with moderate asymmetric induction.

Topology of Event Horizon

OpenAIRE

Siino, Masaru

1997-01-01

The topologies of event horizons are investigated. Considering the existence of the endpoint of the event horizon, it cannot be differentiable. Then there are the new possibilities of the topology of the event horizon though they are excluded in smooth event horizons. The relation between the topology of the event horizon and the endpoint of it is revealed. A torus event horizon is caused by two-dimensional endpoints. One-dimensional endpoints provide the coalescence of spherical event horizo...

Horizon measures

KAUST Repository

Zhang, Eugene

2016-11-28

In this paper we seek to answer the following question: where do contour lines and visible contour lines (silhouette) tend to occur in a 3D surface. Our study leads to two novel shape descriptors, the horizon measure and the visible horizon measure, which we apply to the visualization of 3D shapes including archeological artifacts. In addition to introducing the shape descriptors, we also provide a closed-form formula for the horizon measure based on classical spherical geometry. To compute the visible horizon measure, which depends on the exact computation of the surface visibility function, we instead of provide an image-based approach which can process a model with high complexity within a few minutes.

Michael Roitmann : Kalandus ei ole Eestile ilmselt prioriteetne valdkond / Michael Roitmann ; interv. Marko Saaret

Index Scriptorium Estoniae

Roitmann, Michael

2003-01-01

Ilmunud ka: Delovõje Vedomosti 3. dets. lk. 9. Euroopa Komisjoni kalandusdirektoraadi koordinaator Euroopa Liidu laienemise küsimuses Michael Roitmann juhib tähelepanu Eesti kalanduse suurematele probleemidele ning prognoosib EL-iga liitumise mõju Eesti kalandussektori arengule

Parity horizons in shape dynamics

International Nuclear Information System (INIS)

Herczeg, Gabriel

2016-01-01

I introduce the notion of a parity horizon, and show that many simple solutions of shape dynamics possess them. I show that the event horizons of the known asymptotically flat black hole solutions of shape dynamics are parity horizons and that this notion of parity implies that these horizons possess a notion of CPT invariance that can in some cases be extended to the solution as a whole. I present three new solutions of shape dynamics with parity horizons and find that not only do event horizons become parity horizons in shape dynamics, but observer-dependent horizons and Cauchy horizons do as well. The fact that Cauchy horizons become (singular) parity horizons suggests a general chronology protection mechanism in shape dynamics that prevents the formation of closed timelike curves. (paper)

Book Review: Invitation to Topological Robotics by Michael Farber

DEFF Research Database (Denmark)

Raussen, Martin

2009-01-01

Book Review: Invitaton to Topological Robotics by Michael Farber. Zurich Lectures in Advanced Mathematics, European Mathematical Society (2008), ISBN 978-3-03719-054-8......Book Review: Invitaton to Topological Robotics by Michael Farber. Zurich Lectures in Advanced Mathematics, European Mathematical Society (2008), ISBN 978-3-03719-054-8...

Michael Faraday vs. the Spiritualists

Science.gov (United States)

Hirshfeld, Alan

2006-12-01

In the 1850s, renowned physicist Michael Faraday launched a public campaign against pseudoscience and spiritualism, which were rampant in England at the time. Faraday objected especially to claims that electrical or magnetic forces were responsible for paranormal phenomena, such as table-spinning and communication with the dead. Using scientific methods, Faraday unmasked the deceptions of spiritualists, clairvoyants and mediums and also laid bare the credulity of a public ill-educated in science. Despite his efforts, Victorian society's fascination with the paranormal swelled. Faraday's debacle anticipates current controversies about public science education and the interface between science and religion. This episode is one of many described in the new biography, The Electric Life of Michael Faraday (Walker & Co.), which chronicles Faraday's discoveries and his unlikely rise from poverty to the pinnacle of the English science establishment.

Michael Tomasello: Award for Distinguished Scientific Contributions.

Science.gov (United States)

2015-11-01

The APA Awards for Distinguished Scientific Contributions are presented to persons who, in the opinion of the Committee on Scientific Awards, have made distinguished theoretical or empirical contributions to basic research in psychology. One of the 2015 award winners is Michael Tomasello, who received this award for "outstanding empirical and theoretical contributions to understanding what makes the human mind unique. Michael Tomasello's pioneering research on the origins of social cognition has led to revolutionary insights in both developmental psychology and primate cognition." Tomasello's award citation, biography, and a selected bibliography are presented here. (c) 2015 APA, all rights reserved).

Following Michael Faraday's Footprints

Science.gov (United States)

Galeano, Javier

2011-01-01

Last fall I had the good fortune of receiving financial support to shoot a documentary about Michael Faraday. I took the opportunity to learn more about this great experimentalist and to visit the highlights of places in his life. In this paper, I would like to share a list and description of some of the most remarkable places in London suitable…

Mechanics of apparent horizons

International Nuclear Information System (INIS)

Collins, W.

1992-01-01

An equation for the variation in the surface area of an apparent horizon is derived which has the same form as the thermodynamic relation TdS=dQ. For a stationary vacuum black hole, the expression corresponding to a temperature equals the temperature of the event horizon. Also, if the black hole is perturbed infinitesimally by weak matter and gravitational fields, the area variation of the apparent horizon asymptotically approaches the Hartle-Hawking result for the event horizon. These results support the idea that a local version of black-hole thermodynamics in nonstationary systems can be constructed for apparent horizons

Obituary: Michael James Ledlow, 1964-2004

Science.gov (United States)

Puxley, Philip John; Grashuis, Randon M.

2004-12-01

Michael James Ledlow died on 5 June 2004 from a large, unsuspected brain tumor. Since 2000 he had been on the scientific staff of the Gemini Observatory in La Serena, Chile, initially as a Science Fellow and then as a tenure-track astronomer. Michael was born in Bartlesville, Oklahoma on 1 October 1964 to Jerry and Sharon Ledlow. He obtained his Bachelor Degree in astrophysics at the University of Oklahoma in 1987 and attended the University of New Mexico for his graduate work, obtaining his PhD while studying Galaxy Clusters under Frazer Owen in 1994. From 1995-1997 Michael held a postdoctoral position with Jack Burns at New Mexico State University where he used various astronomical facilities including the VLA and Apache Point Observatory to study distant galaxies. From 1998-2000 Michael rejoined the Physics and Astronomy Department at the University of New Mexico where he was a visiting professor until he moved on to Gemini. At the Gemini Observatory, Mike shared in the excitement, hard work and many long days and nights associated with bringing on-line a major new astronomical facility and its instrumentation. Following its commissioning he assisted visiting observers, supported and took data for many more remote users via the queue system, and for each he showed the same care and attention to detail evident in his own research to ensure that all got the best possible data. His research concentrated on the radio and optical properties of galaxy clusters, especially rich Abell clusters such as A2125, on luminous radio galaxies, including the detection of a powerful double radio source in the "wrong sort of galaxy," the spiral system 0313-192, and on EROs (extremely red objects), dusty galaxies barely detectable at optical wavelengths. Michael thoroughly enjoyed living in Chile and enthusiastically immersed himself in the culture of his surroundings. He and his family were actively involved with the International English Spanish Association in La Serena. He had a

Revisiting event horizon finders

International Nuclear Information System (INIS)

Cohen, Michael I; Pfeiffer, Harald P; Scheel, Mark A

2009-01-01

Event horizons are the defining physical features of black hole spacetimes, and are of considerable interest in studying black hole dynamics. Here, we reconsider three techniques to find event horizons in numerical spacetimes: integrating geodesics, integrating a surface, and integrating a level-set of surfaces over a volume. We implement the first two techniques and find that straightforward integration of geodesics backward in time is most robust. We find that the exponential rate of approach of a null surface towards the event horizon of a spinning black hole equals the surface gravity of the black hole. In head-on mergers we are able to track quasi-normal ringing of the merged black hole through seven oscillations, covering a dynamic range of about 10 5 . Both at late times (when the final black hole has settled down) and at early times (before the merger), the apparent horizon is found to be an excellent approximation of the event horizon. In the head-on binary black hole merger, only some of the future null generators of the horizon are found to start from past null infinity; the others approach the event horizons of the individual black holes at times far before merger.

Interview with Michael Apple: The Biography of a Public Intellectual

Science.gov (United States)

Peters, Michael A.

2015-01-01

Michael W. Apple is the John Bascom Professor of Curriculum and Instruction and Educational Policy Studies in the Departments of Curriculum and Instruction (CI) and Educational Policy Studies (EPS) at the University of Wisconsin-Madison School of Education where he has taught since 1970. Michael Apple is one of the foremost educational theorists…

Michael Beitz: Objects of Communication

Science.gov (United States)

Hoefferle, Mary

2014-01-01

For this Instructional Resource, the author interviewed contemporary sculptor Michael Beitz, who uses art to explore the role of designed objects in human communication and emotional experience. This column was written in response to calls for using Enduring Understandings/Big Ideas (National Coalition for Core Arts Standards, 2013; Stewart &…

78 FR 54298 - Horizons ETFs Management (USA) LLC and Horizons ETF Trust; Notice of Application

Science.gov (United States)

2013-09-03

... ETFs Management (USA) LLC and Horizons ETF Trust; Notice of Application August 27, 2013. AGENCY... Management (USA) LLC (``Horizons'') and Horizons ETF Trust (the ``Trust''). Summary of Application... of the Trust will be the Horizons Active Global Dividend ETF (the ``Initial Fund''), which will seek...

Michael Faraday, media man.

Science.gov (United States)

Fara, Patricia

2006-03-01

Michael Faraday was an enthusiastic portrait collector, and he welcomed the invention of photography not only as a possible means of recording observations accurately, but also as a method for advertising science and its practitioners. This article (which is part of the Science in the Industrial Revolution series) shows that like many eminent scientists, Faraday took advantage of the burgeoning Victorian media industry by posing in various roles.

En bog om Michael Strunge

DEFF Research Database (Denmark)

Mai, Anne-Marie

Antologi med bidrag om Michael Strunges forfatterskab. Bidrag af Anne-Marie Mai, Jørgen Aabenhus, Marianne Stidsen, Moritz Schramm, Tue Andersen Nexø, Lars Bukdahl, Jon Helt Haarder, Rune Kühl er optaget efter fagfællesbedømmelse. Antologien er redigeret af Anne-Marie Mai og Jørgen Aabenhus....

Genomes of planktonic Acidimicrobiales: widening horizons for marine Actinobacteria by metagenomics.

Science.gov (United States)

Mizuno, Carolina Megumi; Rodriguez-Valera, Francisco; Ghai, Rohit

2015-02-10

The genomes of four novel marine Actinobacteria have been assembled from large metagenomic data sets derived from the Mediterranean deep chlorophyll maximum (DCM). These are the first marine representatives belonging to the order Acidimicrobiales and only the second group of planktonic marine Actinobacteria to be described. Their streamlined genomes and photoheterotrophic lifestyle suggest that they are planktonic, free-living microbes. A novel rhodopsin clade, acidirhodopsins, related to freshwater actinorhodopsins, was found in these organisms. Their genomes suggest a capacity to assimilate C2 compounds, some using the glyoxylate bypass and others with the ethylmalonyl-coenzyme A (CoA) pathway. They are also able to derive energy from dimethylsulfopropionate (DMSP), sulfonate, and carbon monoxide oxidation, all commonly available in the marine habitat. These organisms appear to be prevalent in the deep photic zone at or around the DCM. The presence of sister clades to the marine Acidimicrobiales in freshwater aquatic habitats provides a new example of marine-freshwater transitions with potential evolutionary insights. Despite several studies showing the importance and abundance of planktonic Actinobacteria in the marine habitat, a representative genome was only recently described. In order to expand the genomic repertoire of marine Actinobacteria, we describe here the first Acidimicrobidae genomes of marine origin and provide insights about their ecology. They display metabolic versatility in the acquisition of carbon and appear capable of utilizing diverse sources of energy. One of the genomes harbors a new kind of rhodopsin related to the actinorhodopsin clade of freshwater origin that is widespread in the oceans. Our data also support their preference to inhabit the deep chlorophyll maximum and the deep photic zone. This work contributes to the perception of marine actinobacterial groups as important players in the marine environment with distinct and

HORIZON SENSING

Energy Technology Data Exchange (ETDEWEB)

Larry G. Stolarczyk

2003-03-18

With the aid of a DOE grant (No. DE-FC26-01NT41050), Stolar Research Corporation (Stolar) developed the Horizon Sensor (HS) to distinguish between the different layers of a coal seam. Mounted on mining machine cutter drums, HS units can detect or sense the horizon between the coal seam and the roof and floor rock, providing the opportunity to accurately mine the section of the seam most desired. HS also enables accurate cutting of minimum height if that is the operator's objective. Often when cutting is done out-of-seam, the head-positioning function facilitates a fixed mining height to minimize dilution. With this technology, miners can still be at a remote location, yet cut only the clean coal, resulting in a much more efficient overall process. The objectives of this project were to demonstrate the feasibility of horizon sensing on mining machines and demonstrate that Horizon Sensing can allow coal to be cut cleaner and more efficiently. Stolar's primary goal was to develop the Horizon Sensor (HS) into an enabling technology for full or partial automation or ''agile mining''. This technical innovation (R&D 100 Award Winner) is quickly demonstrating improvements in productivity and miner safety at several prominent coal mines in the United States. In addition, the HS system can enable the cutting of cleaner coal. Stolar has driven the HS program on the philosophy that cutting cleaner coal means burning cleaner coal. The sensor, located inches from the cutting bits, is based upon the physics principles of a Resonant Microstrip Patch Antenna (RMPA). When it is in proximity of the rock-coal interface, the RMPA impedance varies depending on the thickness of uncut coal. The impedance is measured by the computer-controlled electronics and then sent by radio waves to the mining machine. The worker at the machine can read the data via a Graphical User Interface, displaying a color-coded image of the coal being cut, and direct the machine

Michael Polanyi: Patriarch of Chemical Dynamics and Tacit Knowing.

Science.gov (United States)

Herschbach, Dudley R

2017-03-20

Connecting Science and the Humanities was the title of the symposium on Michael Polanyi that took place at the Technische Universität Berlin (Technical University of Berlin) in October 2016. This essay, which appraises the scientific and philosophical contributions of Michael Polanyi, is based on the presentation given by Dr. Herschbach on this occasion. In the photograph: Polanyi in 1931. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

What happens at the horizon(s) of an extreme black hole?

International Nuclear Information System (INIS)

Murata, Keiju; Reall, Harvey S; Tanahashi, Norihiro

2013-01-01

A massless scalar field exhibits an instability at the event horizon of an extreme black hole. We study numerically the nonlinear evolution of this instability for spherically symmetric perturbations of an extreme Reissner–Nordstrom (RN) black hole. We find that generically the endpoint of the instability is a non-extreme RN solution. However, there exist fine-tuned initial perturbations for which the instability never decays. In this case, the perturbed spacetime describes a time-dependent extreme black hole. Such solutions settle down to extreme RN outside, but not on, the event horizon. The event horizon remains smooth but certain observers who cross it at late time experience large gradients there. Our results indicate that these dynamical extreme black holes admit a C 1 extension across an inner (Cauchy) horizon. (paper)

Video interview with Michael Dell

CERN Multimedia

CERN Bulletin

2010-01-01

Michael Dell, founder and presently Chairman of the Board of Directors and Chief Executive Office of the DELL computer company visited CERN on Tuesday 26th January 2010. The Bulletin and the Video productions team had the opportunity to meet him. The video interview is transcribed for your convenience.   Michael S. Dell with CERN Director-General Rolf Heuer. What motivated you to come and visit CERN? I obviously heard about the great science and research has going on here, and DELL is very pleased to be a partner and providing a lot of the computers to analyse the data and I really wanted to see for myself in person, some of the great science that is going on here. What is your view on fundamental research in IT, and in general? I think if you look at the field of science in the last hundred years, we have been able to solve a lot of problems, but there are still lots of unsolved problems and unsolved mysteries. And it is only through basic fundamental research that we will address these probl...

Spacetimes foliated by Killing horizons

International Nuclear Information System (INIS)

Pawlowski, Tomasz; Lewandowski, Jerzy; Jezierski, Jacek

2004-01-01

It seems to be expected that a horizon of a quasi-local type, such as a Killing or an isolated horizon, by analogy with a globally defined event horizon, should be unique in some open neighbourhood in the spacetime, provided the vacuum Einstein or the Einstein-Maxwell equations are satisfied. The aim of our paper is to verify whether that intuition is correct. If one can extend a so-called Kundt metric, in such a way that its null, shear-free surfaces have spherical spacetime sections, the resulting spacetime is foliated by so-called non-expanding horizons. The obstacle is Kundt's constraint induced at the surfaces by the Einstein or the Einstein-Maxwell equations, and the requirement that a solution be globally defined on the sphere. We derived a transformation (reflection) that creates a solution to Kundt's constraint out of data defining an extremal isolated horizon. Using that transformation, we derived a class of exact solutions to the Einstein or Einstein-Maxwell equations of very special properties. Each spacetime we construct is foliated by a family of the Killing horizons. Moreover, it admits another, transversal Killing horizon. The intrinsic and extrinsic geometries of the transversal Killing horizon coincide with the one defined on the event horizon of the extremal Kerr-Newman solution. However, the Killing horizon in our example admits yet another Killing vector tangent to and null at it. The geometries of the leaves are given by the reflection

Reflections on Michael Hardt and Antonio Negri’s Book “Assembly”

Directory of Open Access Journals (Sweden)

Christian Fuchs

2017-10-01

Full Text Available This contribution presents reflections on Michael Hardt and Antonio Negri’s book “Assembly” (2017, Oxford: Oxford University Press, ISBN 978-0190677961. Keywords: assembly, Michael Hardt, Antonio Negri, multitude, common, entrepreneurship of the multitude, the new Prince, digital capitalism, digital assemblage, neoliberalism, finance

Radiation curable Michael addition compounds

International Nuclear Information System (INIS)

Gruber, G.W.; Friedlander, C.B.; McDonald, W.H.; Dowbenko, R.

1979-01-01

Radiation polymerizable acrylyloxy-containing reaction products are provided from Michael addition reaction of an amide containing at least two acrylate groups with a primary or secondary amine. The resulting amine adducts of the amide, which contain at least one acrylate group per molecule, possesses high cure rates in air and are useful in compositions for forming coatings. (author)

Markets, Marx, Modernity and Mathematics Education: A Response to Michael Apple.

Science.gov (United States)

Gates, Peter

This paper is a response to Michael Apple's paper, "What Postmodernists Forget: Cultural Capital and Official Knowledge." The paper advocates Michael's identification of the current dangers and processes of the growth of new right ideologies in the development of subjectivity, society, and education. The differences in success in the education…

Asymmetric Michael Addition Mediated by Chiral Ionic Liquids.

Science.gov (United States)

Suzuki, Yumiko

2018-06-01

Chiral ionic liquids with a focus on their applications in asymmetric Michael additions and related reactions were reviewed. The examples were classified on the basis of the mode of asymmetric induction (e.g., external induction/non-covalent interaction or internal induction/covalent bond formation), the roles in reactions (as a solvent or catalyst), and their structural features (e.g., imidazolium-based chiral cations, other chiral oniums; proline derivatives). Most of the reactions with high chiral induction are Michael addition of ketones or aldehydes to chalcones or nitrostyrenes where proline-derived chiral ionic liquids catalyze the reaction through enamine/ iminium formation. Many reports demonstrate the recyclability of ionic liquid-tagged pyrrolidines.

Cosmological and black hole apparent horizons

CERN Document Server

Faraoni, Valerio

2015-01-01

This book overviews the extensive literature on apparent cosmological and black hole horizons. In theoretical gravity, dynamical situations such as gravitational collapse, black hole evaporation, and black holes interacting with non-trivial environments, as well as the attempts to model gravitational waves occurring in highly dynamical astrophysical processes, require that the concept of event horizon be generalized. Inequivalent notions of horizon abound in the technical literature and are discussed in this manuscript. The book begins with a quick review of basic material in the first one and a half chapters, establishing a unified notation. Chapter 2 reminds the reader of the basic tools used in the analysis of horizons and reviews the various definitions of horizons appearing in the literature. Cosmological horizons are the playground in which one should take baby steps in understanding horizon physics. Chapter 3 analyzes cosmological horizons, their proposed thermodynamics, and several coordinate systems....

Conformal Killing horizons and their thermodynamics

Science.gov (United States)

Nielsen, Alex B.; Shoom, Andrey A.

2018-05-01

Certain dynamical black hole solutions can be mapped to static spacetimes by conformal metric transformations. This mapping provides a physical link between the conformal Killing horizon of the dynamical black hole and the Killing horizon of the static spacetime. Using the Vaidya spacetime as an example, we show how this conformal relation can be used to derive thermodynamic properties of such dynamical black holes. Although these horizons are defined quasi-locally and can be located by local experiments, they are distinct from other popular notions of quasi-local horizons such as apparent horizons. Thus in the dynamical Vaidya spacetime describing constant accretion of null dust, the conformal Killing horizon, which is null by construction, is the natural horizon to describe the black hole.

Spacetimes containing slowly evolving horizons

International Nuclear Information System (INIS)

Kavanagh, William; Booth, Ivan

2006-01-01

Slowly evolving horizons are trapping horizons that are ''almost'' isolated horizons. This paper reviews their definition and discusses several spacetimes containing such structures. These include certain Vaidya and Tolman-Bondi solutions as well as (perturbatively) tidally distorted black holes. Taking into account the mass scales and orders of magnitude that arise in these calculations, we conjecture that slowly evolving horizons are the norm rather than the exception in astrophysical processes that involve stellar-scale black holes

Examples of plasma horizons

International Nuclear Information System (INIS)

Hanni, R.S.

1975-01-01

The concept of the plasma horizon, defined as the boundary of the region in which an infinitely thin plasma can be supported against Coulomb attraction by a magnetic field, shows that the argument of selective accretion does not rule out the existence of charged black holes embedded in a conducting plasma. A detailed account of the covariant definition of plasma horizon is given and some examples of plasma horizons are presented. 7 references

Aza-Michael reaction: achievements and prospects

International Nuclear Information System (INIS)

Rulev, Alexander Yu

2011-01-01

Data published in the last 10 years on the use of the aza-Michael reaction in organic synthesis are described systematically. The attention is focused on environmentally friendly processes following green chemistry principles and on methods for the synthesis of compounds that are difficult to access by other routes.

Michael Jackson's Sound Stages

OpenAIRE

Morten Michelsen

2012-01-01

In order to discuss analytically spatial aspects of recorded sound William Moylan’s concept of ‘sound stage’ is developed within a musicological framework as part of a sound paradigm which includes timbre, texture and sound stage. Two Michael Jackson songs (‘The Lady in My Life’ from 1982 and ‘Scream’ from 1995) are used to: a) demonstrate the value of such a conceptualisation, and b) demonstrate that the model has its limits, as record producers in the 1990s began ignoring the conventions of...

Studying Teachers and Schools: Michael Pressley's Legacy and Directions for Future Research

Science.gov (United States)

Mohan, Lindsey; Lundeberg, Mary A.; Reffitt, Kelly

2008-01-01

Much of Michael Pressley's work during the past decade focused on the nature of highly effective, engaging literacy instruction. Michael Pressley believed that studying effective teachers and schools had the potential to influence more engaging and effective teaching, especially in underresourced schools. First, we describe the grounded…

En memoria de Michael Jiménez (1948-2001

Directory of Open Access Journals (Sweden)

Mauricio Archila Neira

2001-01-01

Full Text Available El 1 de septiembre de 2001 murió el historiador Michael Jiménez. Su apellido provenía de España de donde emigró su abuelo en busca de mejor suerte al otro lado del Atlántico. Nacido en el pequeño pueblo de Merced, California (Estados Unidos en agosto de 1948 en el seno de una familia obrera, Michael vivió su infancia en Colombia. A fines de ese año, su padre se desplazó a estas tierras para ser funcionario de la Texas, una multinacional petrolera que tenía sus reales en Puerto Boyacá. Michael estudió en el colegio Nueva Granada -becado por la Texas- hasta los catorce años. En dicho colegio fue compañero de pupitre de Herbert Braun, descendiente a su vez de una familia de emigrantes a Colombia, y con quien la vida lo juntaría de nuevo en las tierras del norte y en oficios similares.

Asymmetric Michael Addition Mediated by Chiral Ionic Liquids

Science.gov (United States)

Suzuki, Yumiko

2018-01-01

Chiral ionic liquids with a focus on their applications in asymmetric Michael additions and related reactions were reviewed. The examples were classified on the basis of the mode of asymmetric induction (e.g., external induction/non-covalent interaction or internal induction/covalent bond formation), the roles in reactions (as a solvent or catalyst), and their structural features (e.g., imidazolium-based chiral cations, other chiral oniums; proline derivatives). Most of the reactions with high chiral induction are Michael addition of ketones or aldehydes to chalcones or nitrostyrenes where proline-derived chiral ionic liquids catalyze the reaction through enamine/ iminium formation. Many reports demonstrate the recyclability of ionic liquid-tagged pyrrolidines. PMID:29861702

Stringy horizons

Energy Technology Data Exchange (ETDEWEB)

Giveon, Amit [Racah Institute of Physics, The Hebrew University,Jerusalem 91904 (Israel); Itzhaki, Nissan [Physics Department, Tel-Aviv University,Ramat-Aviv, 69978 (Israel); Kutasov, David [EFI and Department of Physics, University of Chicago,5640 S. Ellis Av., Chicago, IL 60637 (United States)

2015-06-11

We argue that classical (α{sup ′}) effects qualitatively modify the structure of Euclidean black hole horizons in string theory. While low energy modes experience the geometry familiar from general relativity, high energy ones see a rather different geometry, in which the Euclidean horizon can be penetrated by an amount that grows with the radial momentum of the probe. We discuss this in the exactly solvable SL(2,ℝ)/U(1) black hole, where it is a manifestation of the black hole/Sine-Liouville duality.

Tribute to Professor Anthony J. McMichael

Directory of Open Access Journals (Sweden)

Ashwin Swaminathan

2014-11-01

Full Text Available Emeritus Professor A. J. “Tony” McMichael (1942–2014 was an internationally renowned and pioneering Australian academic and advocate in epidemiology, who was passionate about understanding the influences of the environment on human health. In an illustrious career spanning more than four decades, he made significant contributions to the scientific community and policy discourse—including ground-breaking research related to the health of children. McMichael was a prolific academic writer with over 300 peer-reviewed papers; 160 book chapters and two sole-authored books. However, his outstanding talent was for integrating complex and seemingly unrelated strands from the environmental and health sciences into a cohesive narrative—and highlighting its relevance to lay persons, scientists and governments alike. He was instrumental in validating this nascent field of research and inspiring many others to follow his lead.

Michael Heyrovsky, in memoriam (1932-2017)

Czech Academy of Sciences Publication Activity Database

Barek, J.; Černý, Slavoj; Herman, Zdeněk; Jindra, Jiří; Paleček, Emil

2017-01-01

Roč. 29, č. 8 (2017), s. 2001-2002 ISSN 1040-0397 Institutional support: RVO:68378114 ; RVO:61388955 ; RVO:68081707 Keywords : Michael Heyrovský Subject RIV: AB - History OBOR OECD: History (history of science and technology to be 6.3, history of specific sciences to be under the respective headings) Impact factor: 2.851, year: 2016

75 FR 62635 - Proposed Information Collection (Patient Satisfaction Survey Michael E. DeBakey Home Care Program...

Science.gov (United States)

2010-10-12

... Collection (Patient Satisfaction Survey Michael E. DeBakey Home Care Program) Activity: Comment Request... determine patients' satisfaction with services provided by or through the Michael E. DeBakey Home Care...: Patient Satisfaction Survey Michael E. DeBakey Home Care Program, VA Form 10-0476. OMB Control Number...

A DATABASE FOR TRACKING TOXICOGENOMIC SAMPLES AND PROCEDURES WITH GENOMIC, PROTEOMIC AND METABONOMIC COMPONENTS

Science.gov (United States)

A Database for Tracking Toxicogenomic Samples and Procedures with Genomic, Proteomic and Metabonomic Components Wenjun Bao1, Jennifer Fostel2, Michael D. Waters2, B. Alex Merrick2, Drew Ekman3, Mitchell Kostich4, Judith Schmid1, David Dix1Office of Research and Developmen...

Michael Hauskeller: Sex and the Posthuman Condition

NARCIS (Netherlands)

Miller, Lantz Eugene

2016-01-01

This new book from Michael Hauskeller explores the currently marketed or projected sex/love products that exhibit some trait of so-called “posthumanistic” theory or design. These products are so designated because of their intention to fuse high technologies, including robotics and computing, with

Entropy of black holes with multiple horizons

Science.gov (United States)

He, Yun; Ma, Meng-Sen; Zhao, Ren

2018-05-01

We examine the entropy of black holes in de Sitter space and black holes surrounded by quintessence. These black holes have multiple horizons, including at least the black hole event horizon and a horizon outside it (cosmological horizon for de Sitter black holes and "quintessence horizon" for the black holes surrounded by quintessence). Based on the consideration that the two horizons are not independent each other, we conjecture that the total entropy of these black holes should not be simply the sum of entropies of the two horizons, but should have an extra term coming from the correlations between the two horizons. Different from our previous works, in this paper we consider the cosmological constant as the variable and employ an effective method to derive the explicit form of the entropy. We also try to discuss the thermodynamic stabilities of these black holes according to the entropy and the effective temperature.

Aza-Michael Mono-addition Using Acidic Alumina under Solventless Conditions

Directory of Open Access Journals (Sweden)

Giovanna Bosica

2016-06-01

Full Text Available Aza-Michael reactions between primary aliphatic and aromatic amines and various Michael acceptors have been performed under environmentally-friendly solventless conditions using acidic alumina as a heterogeneous catalyst to selectively obtain the corresponding mono-adducts in high yields. Ethyl acrylate was the main acceptor used, although others such as acrylonitrile, methyl acrylate and acrylamide were also utilized successfully. Bi-functional amines also gave the mono-adducts in good to excellent yields. Such compounds can serve as intermediates for the synthesis of anti-cancer and antibiotic drugs.

Variable horizon in a peridynamic medium.

Energy Technology Data Exchange (ETDEWEB)

Silling, Stewart Andrew; Littlewood, David John; Seleson, Pablo

2014-10-01

A notion of material homogeneity is proposed for peridynamic bodies with vari- able horizon but constant bulk properties. A relation is derived that scales the force state according to the position-dependent horizon while keeping the bulk properties un- changed. Using this scaling relation, if the horizon depends on position, artifacts called ghost forces may arise in a body under homogeneous deformation. These artifacts de- pend on the second derivative of horizon and can be reduced by use of a modified equilibrium equation using a new quantity called the partial stress . Bodies with piece- wise constant horizon can be modeled without ghost forces by using a technique called a splice between the regions. As a limiting case of zero horizon, both partial stress and splice techniques can be used to achieve local-nonlocal coupling. Computational examples, including dynamic fracture in a one-dimensional model with local-nonlocal coupling, illustrate the methods.

Black hole versus cosmological horizon entropy

International Nuclear Information System (INIS)

Davis, Tamara M; Davies, P C W; Lineweaver, Charles H

2003-01-01

The generalized second law of thermodynamics states that entropy always increases when all event horizons are attributed with an entropy proportional to their area. We test the generalized second law by investigating the change in entropy when dust, radiation and black holes cross a cosmological event horizon. We generalize for flat, open and closed Friedmann-Robertson-Walker universes by using numerical calculations to determine the cosmological horizon evolution. In most cases, the loss of entropy from within the cosmological horizon is more than balanced by an increase in cosmological event horizon entropy, maintaining the validity of the generalized second law of thermodynamics. However, an intriguing set of open universe models shows an apparent entropy decrease when black holes disappear over the cosmological event horizon. We anticipate that this apparent violation of the generalized second law will disappear when solutions are available for black holes embedded in arbitrary backgrounds

Neighborhoods of isolated horizons and their stationarity

International Nuclear Information System (INIS)

Lewandowski, Jerzy; Pawłowski, Tomasz

2014-01-01

A distinguished (invariant) Bondi-like coordinate system is defined in the spacetime neighborhood of a non-expanding horizon of arbitrary dimension via geometry invariants of the horizon. With its use, the radial expansion of a spacetime metric about the horizon is provided and the free data needed to specify it up to a given order are determined in spacetime dimension 4. For the case of an electro-vacuum horizon in four-dimensional spacetime, the necessary and sufficient conditions for the existence of a Killing field at its neighborhood are identified as differential conditions for the horizon data and data for the null surface transversal to the horizon. (paper)

Horizon Detection In The Visible Spectrum

Science.gov (United States)

2016-09-01

processing units, to the software-based models in [7] and [8]. B. DEFINING THE HORIZON The horizon, according to the Oxford English Dictionary , is “the...Ed. Dordrecht, Holland: D. Reidel Publishing Company, 1978. [10] “horizon,” Oxford English Dictionary Online, 2016.[Online]. Available: http

Electrodynamics of the event horizon

International Nuclear Information System (INIS)

Punsly, B.; Coroniti, F.V.

1989-01-01

This paper is an investigation of the electrodynamics of the event horizon of a Kerr black hole. It is demonstrated that the event horizon behaves quite generally as an asymptotic vacuum infinity for axisymmetric, charge-neutral, accreting electromagnetic sources. This is in contrast with the general notion that the event horizon can be treated as an imperfect conductive membrane with a surface impedance of 4π/c. The conductive-membrane model has been incorporated into the more sophisticated membrane paradigm of Thorne, Price, and Macdonald by supplementing the model with the full equations of general relativity. In certain situations (in particular those of astrophysical interest), the conductive-membrane interpretation forms the appropriate set of pictures and images in the membrane paradigm. In this paper we reevaluate the specific gedanken experiments that were originally used to motivate the paradigm. We find that great care must be exercised if the detailed interaction of a black hole's external gravitational field with a magnetized plasma is modeled by the electrodynamics of the conductive horizon membrane. For ingoing flows of plasma or electromagnetic waves (when the hole is passively accepting information), the interpretation of the horizon as a vacuum infinity is equivalent to an imperfect conductor with a surface impedance of 4π/c (the impedance of the vacuum). In situations when an imperfect conductor should radiate information (such as a Faraday wheel) the event horizon cannot, since it is an infinity. The event horizon does not behave quite generally as an imperfect conductor, but has electrodynamic properties unique to itself

Professor Michael Levitt

Directory of Open Access Journals (Sweden)

Gemma-Louise Davies

2015-10-01

Full Text Available Professor Michael Levitt (Stanford University, USA won the 2013 Nobel Prize in Chemistry for the development of multiscale models for complex chemical systems—computational tools which can calculate the course of chemical reactions. Professor Levitt was born in Pretoria, South Africa; he came to the UK on a summer vacation aged 16, where he decided to stay and study for his A‑levels. His interest in the physics of living systems drove him to study biophysics at King’s College London, before securing a PhD position at the Laboratory of Molecular Biology in Cambridge. In the interim year between his degree and beginning his PhD, Professor Levitt worked at the Weizmann Institute of Science in Israel, where he met his future wife. They married later that year and moved to Cambridge, where their three children were born. After completing his PhD, he spent time working in Israel, Cambridge, the Salk Institute and Stanford (both California. Since 1986, he has split his time between Israel and California. Outside of science, he is a keen hiker and he is well-known to have attended the eclectic ‘Burning Man’ Festival in California.[1] Professor Levitt visited the University of Warwick to speak at the Computational Molecular Science Annual Conference in March 2015. In this interview, Dr Gemma-Louise Davies, an Institute of Advanced Study Global Research Fellow, spoke to Professor Levitt about the importance of Interdisciplinarity in his field, role models in Academia, and his plans for the future. Image: Professor Michael Levitt (left with Dr Scott Habershon (right, organiser of the 2015 Computational Molecular Science Annual Conference during his visit to the University of Warwick in March 2015. [1] ‘Burning Man’ is a unique annual festival dedicated to community, art, music, self-expression and self-reliance. Tens of thousands of people flock to this temporary metropolis built in the Californian desert.

Fiber-optical analog of the event horizon.

Science.gov (United States)

Philbin, Thomas G; Kuklewicz, Chris; Robertson, Scott; Hill, Stephen; König, Friedrich; Leonhardt, Ulf

2008-03-07

The physics at the event horizon resembles the behavior of waves in moving media. Horizons are formed where the local speed of the medium exceeds the wave velocity. We used ultrashort pulses in microstructured optical fibers to demonstrate the formation of an artificial event horizon in optics. We observed a classical optical effect: the blue-shifting of light at a white-hole horizon. We also showed by theoretical calculations that such a system is capable of probing the quantum effects of horizons, in particular Hawking radiation.

SuchThatCast Episode 6: Michael Boylan

NARCIS (Netherlands)

Soraker, Johnny

2012-01-01

Michael Boylan is the John J. McDonnell jr chair in Ethics, and professor and chair of the philosophy department at Marymount University in Arlington, Virginia. In addition to being a poet and novelist, he has written more than 100 published articles and 25 books primarily in ethics, social and

Double Michael Addition Reaction of Bischalcone under Ultrasound

Institute of Scientific and Technical Information of China (English)

LI,Ji-Tai; XU,Wen-Zhi; CHEN,Guo-Feng; LI,Tong-Shuang

2004-01-01

@@ The Michael addition of 1,5-diaryl-1,4-pentadien-3-ones with active methylene compounds has been the subjects of many investigations. Ultrasound has increasingly been used in organic synthesis in the last three decades. Compared with traditional methods, this method is more convenient and easily controlled. A large number of organic reactions can be carried out in higher yield, shorter reaction time or milder conditions under ultrasonic irradiation. KF/Al2O3 as a useful solid supported catalyst has received considerable attention because of their high level of chemoselectivity and environmental compatibility as well as simplicity of operation and their ready availability at low cost. Herein we report the double Michael addition of dibenzalacetone with active methlene compounds such as dimethyl malonate, diethyl malonate,methyl cyanoacetate and ethyl cyanoacetate catalyzed by KF/Al2O3 under ultrasound irradiation.

Optimal investment horizons

Science.gov (United States)

Simonsen, I.; Jensen, M. H.; Johansen, A.

2002-06-01

In stochastic finance, one traditionally considers the return as a competitive measure of an asset, i.e., the profit generated by that asset after some fixed time span Δt, say one week or one year. This measures how well (or how bad) the asset performs over that given period of time. It has been established that the distribution of returns exhibits ``fat tails'' indicating that large returns occur more frequently than what is expected from standard Gaussian stochastic processes [1-3]. Instead of estimating this ``fat tail'' distribution of returns, we propose here an alternative approach, which is outlined by addressing the following question: What is the smallest time interval needed for an asset to cross a fixed return level of say 10%? For a particular asset, we refer to this time as the investment horizon and the corresponding distribution as the investment horizon distribution. This latter distribution complements that of returns and provides new and possibly crucial information for portfolio design and risk-management, as well as for pricing of more exotic options. By considering historical financial data, exemplified by the Dow Jones Industrial Average, we obtain a novel set of probability distributions for the investment horizons which can be used to estimate the optimal investment horizon for a stock or a future contract.

VMware horizon view essentials

CERN Document Server

von Oven, Peter

2014-01-01

If you are a desktop administrator or an end user of a computing project team looking to speed up to the latest VMware Horizon View solution, then this book is perfect for you. It is your ideal companion to deploy a solution to centrally manage and virtualize your desktop estate using Horizon View 6.0.

Michael Frayn visits CERN

CERN Multimedia

2007-01-01

Award-winning playwright and novelist Michael Frayn gave a guest lecture in the main auditorium at CERN on Friday 15 March about his new book The Human Touch: Our Part in the Creation of the Universe. The lecture focused on cosmology and philosophy and the limitations that language places on our ability to understand the creation of a universe in which we seem to play such a small part. In addition to his novels and plays, which include Copenhagen, a play about the 1941 meeting between German physicist Werner Heisenberg and Danish physicist Niels Bohr, Frayn has translated several works from Russian, including plays by Chekhov and Tolstoy.

Between Irish National Cinema and Hollywood: Neil Jordan’s Michael Collins

Directory of Open Access Journals (Sweden)

Raita Merivirta-Chakrabarti

2007-03-01

Full Text Available When Neil Jordan’s film Michael Collins was released in 1996, it was seen by some as a Hollywood epic, by others as a great national film. I would argue that Michael Collins combines these two traditions and occupies a space between Irish national cinema and Hollywood. The subject matter, the creative talent and the locations were Irish and the film was produced by using the Irish filmmaking infrastructure and the Irish government’s support mechanisms, but it was largely financed and distributed by a Hollywood studio. Also, to make it more appealing especially globally, but probably also locally (since Hollywood is now the international standard, it makes use of Hollywood conventions, making it accessible to international audiences as well. Despite the Hollywood mode, the fact remains that Michael Collins is a national film text, and Jordan does not make too many concessions to the non-Irish audiences.

Entropy of black holes with multiple horizons

Directory of Open Access Journals (Sweden)

Yun He

2018-05-01

Full Text Available We examine the entropy of black holes in de Sitter space and black holes surrounded by quintessence. These black holes have multiple horizons, including at least the black hole event horizon and a horizon outside it (cosmological horizon for de Sitter black holes and “quintessence horizon” for the black holes surrounded by quintessence. Based on the consideration that the two horizons are not independent each other, we conjecture that the total entropy of these black holes should not be simply the sum of entropies of the two horizons, but should have an extra term coming from the correlations between the two horizons. Different from our previous works, in this paper we consider the cosmological constant as the variable and employ an effective method to derive the explicit form of the entropy. We also try to discuss the thermodynamic stabilities of these black holes according to the entropy and the effective temperature.

Reframing Michael Scott: Exploring Inappropriate Workplace Communication

Science.gov (United States)

Schaefer, Zachary A.

2010-01-01

Individuals who work in professional settings interact with others who may exhibit a variety of cultural beliefs and decision-making approaches. Page (2007) argues that cognitive diversity (i.e., how people approach and attempt to solve problems) is a vital asset in effective organizations. Michael Scott, who portrays the inept main character on…

Michael Moore kaevati kohtusse pettuse eest / Mari Rebane

Index Scriptorium Estoniae

Rebane, Mari

2006-01-01

Dokumentaalfilm "9/11 Fahrenheiti" ("Fahrenheit 9/11") : režissöör Michael Moore : USA 2004. Iraagi sõja invaliidistunud veteran andis režissööri kohtusse teda kujutavate flmikaadrite loata ja tenentsliku kasutamise pärast

'The televising of science is a process of television': establishing Horizon, 1962-1967.

Science.gov (United States)

Boon, Timothy

2015-03-01

BBC Television's Horizon series, fifty years old on 2 May 2014, despite its significance to the history of the public culture of science, has been little studied. This microhistorical account follows the gestation and early years of the programme, demonstrating how it established a social and cultural account of science. This was a result of televisual factors, notably the determination to follow the format of the successful arts television programme Monitor. It illuminates how the processes of television production, with a handful of key participants - Aubrey Singer, Gerald Leach, Philip Daly, Gordon Rattray Taylor, Ramsay Short, Michael Peacock and Robert Reid - established the format of the programme. This occurred over seventeen months of prior preparation followed by three troubled years of seeking to establish a stable form. This was finally achieved in 1967 when the programme adopted a film documentary approach after extended attempts at making it as a studio-based magazine programme. The story has implications for understanding the social accounts of science that were circulating in the key decade of the 1960s.

Cartan invariants and event horizon detection

Science.gov (United States)

Brooks, D.; Chavy-Waddy, P. C.; Coley, A. A.; Forget, A.; Gregoris, D.; MacCallum, M. A. H.; McNutt, D. D.

2018-04-01

We show that it is possible to locate the event horizon of a black hole (in arbitrary dimensions) by the zeros of certain Cartan invariants. This approach accounts for the recent results on the detection of stationary horizons using scalar polynomial curvature invariants, and improves upon them since the proposed method is computationally less expensive. As an application, we produce Cartan invariants that locate the event horizons for various exact four-dimensional and five-dimensional stationary, asymptotically flat (or (anti) de Sitter), black hole solutions and compare the Cartan invariants with the corresponding scalar curvature invariants that detect the event horizon.

Generalized Robertson-Walker Space-Time Admitting Evolving Null Horizons Related to a Black Hole Event Horizon.

Science.gov (United States)

Duggal, K L

2016-01-01

A new technique is used to study a family of time-dependent null horizons, called " Evolving Null Horizons " (ENHs), of generalized Robertson-Walker (GRW) space-time [Formula: see text] such that the metric [Formula: see text] satisfies a kinematic condition. This work is different from our early papers on the same issue where we used (1 + n )-splitting space-time but only some special subcases of GRW space-time have this formalism. Also, in contrast to previous work, we have proved that each member of ENHs is totally umbilical in [Formula: see text]. Finally, we show that there exists an ENH which is always a null horizon evolving into a black hole event horizon and suggest some open problems.

Holography beyond the horizon and cosmic censorship

International Nuclear Information System (INIS)

Levi, Thomas S.; Ross, Simon F.

2003-01-01

We investigate the description of the region behind the event horizon in rotating black holes in the AdS conformal field theory correspondence, using the rotating Banados-Teitelboim-Zanelli black hole as a concrete example. We extend a technique introduced by Kraus, Ooguri, and Shenker, based on analytically continuing amplitudes defined in a Euclidean space, to include rotation. In the rotating case, boundary amplitudes again have two different bulk descriptions, involving either integration only over the regions outside the black holes' event horizon, or integration over this region and the region between the event horizon and the Cauchy horizon (inner horizon). We argue that generally, the holographic map will relate the field theory to the region bounded by the Cauchy horizons in spacetime. We also argue that these results suggest that the holographic description of black holes will satisfy strong cosmic censorship

Michael Haneke film Euroopa parim / M. T.

Index Scriptorium Estoniae

M. T.

2005-01-01

IX PÖFFil linastuv Michael Haneke film "Varjatud" ("Cache") võitis laupäeval mitu Euroopa Filmiakadeemia auhinda, selhulgas parima filmi, parima lavastaja, parima meesnäitleja (Daniel Auteuil) ja FIPRESCI auhinna. Parim naisnäitleja - Julia Jentsch ("Sophie Scholli viimased päevad"), operaator - Franz Lustig ("Don't Come Knocking"), stsenaarium - Hany Abu-Assad, Bero Beyer ("Kohe paradiisi")

Nearly Finished Genomes Produced Using Gel Microdroplet Culturing (Seventh Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting 2012)

Energy Technology Data Exchange (ETDEWEB)

Fitzsimmons, Michael

2012-06-01

Michael Fitzsimmons from Los Alamos National Laboratory gives a talk titled "Nearly Finished Genomes Produced Using Gel Microdroplet Culturing" at the 7th Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting held in June, 2012 in Santa Fe, NM.

Horizon Entropy from Quantum Gravity Condensates.

Science.gov (United States)

Oriti, Daniele; Pranzetti, Daniele; Sindoni, Lorenzo

2016-05-27

We construct condensate states encoding the continuum spherically symmetric quantum geometry of a horizon in full quantum gravity, i.e., without any classical symmetry reduction, in the group field theory formalism. Tracing over the bulk degrees of freedom, we show how the resulting reduced density matrix manifestly exhibits a holographic behavior. We derive a complete orthonormal basis of eigenstates for the reduced density matrix of the horizon and use it to compute the horizon entanglement entropy. By imposing consistency with the horizon boundary conditions and semiclassical thermodynamical properties, we recover the Bekenstein-Hawking entropy formula for any value of the Immirzi parameter. Our analysis supports the equivalence between the von Neumann (entanglement) entropy interpretation and the Boltzmann (statistical) one.

Event horizon image within black hole shadow

OpenAIRE

Dokuchaev, V. I.; Nazarova, N. O.

2018-01-01

The external border of the black hole shadow is washed out by radiation from matter plunging into black hole and approaching the event horizon. This effect will crucially influence the results of future observations by the Event Horizon Telescope. We show that gravitational lensing of the luminous matter plunging into black hole provides the event horizon visualization within black hole shadow. The lensed image of the event horizon is formed by the last highly red-shifted photons emitted by t...

TU-C-HORIZONS-01: The Expanding Horizons Travel Grant Program: ePosters and Discussion

International Nuclear Information System (INIS)

Siewerdsen, J; Jeraj, R

2016-01-01

The Expanding Horizons travel grant program provides opportunity for students and trainees to broaden the scope of scientific meetings they attend and gain insight from research outside traditional domains of medical physics. Through participation in such conferences, early-career researchers are introduced to new topics with relevance to medical physics research as a means to expand the scientific horizons of our discipline. This year, 21 Expanding Horizons travel grants were awarded, granting travel to 17 conferences, including: Radiomics, the World Molecular Imaging Society (WMIS), the 3D Printing Conference and Expo, the GPU Technology Conference, the SIAM Imaging Science Conference, the Human Brain Mapping Conference, the OSA Conference on Clinical and Translational Biophotonics, the Society for Neuroscience, the AACR Conference on Tumor Microenvironment, and the Conference on Knowledge Discovery and Data Mining. The Expanding Horizons electronic poster session gives a venue for AAPM conference attendees to meet and discuss with awardees, learn the hot topics and emerging research areas presented at these conferences, and understand the relevance to future medical physics research.

TU-C-HORIZONS-01: The Expanding Horizons Travel Grant Program: ePosters and Discussion

Energy Technology Data Exchange (ETDEWEB)

Siewerdsen, J [Johns Hopkins University, Baltimore, MD (United States); Jeraj, R [University of Wisconsin, Madison, WI (United States)

2016-06-15

The Expanding Horizons travel grant program provides opportunity for students and trainees to broaden the scope of scientific meetings they attend and gain insight from research outside traditional domains of medical physics. Through participation in such conferences, early-career researchers are introduced to new topics with relevance to medical physics research as a means to expand the scientific horizons of our discipline. This year, 21 Expanding Horizons travel grants were awarded, granting travel to 17 conferences, including: Radiomics, the World Molecular Imaging Society (WMIS), the 3D Printing Conference and Expo, the GPU Technology Conference, the SIAM Imaging Science Conference, the Human Brain Mapping Conference, the OSA Conference on Clinical and Translational Biophotonics, the Society for Neuroscience, the AACR Conference on Tumor Microenvironment, and the Conference on Knowledge Discovery and Data Mining. The Expanding Horizons electronic poster session gives a venue for AAPM conference attendees to meet and discuss with awardees, learn the hot topics and emerging research areas presented at these conferences, and understand the relevance to future medical physics research.

Brändi näkyy musiikkivideossa : Esimerkkitapaus Michael Jackson

OpenAIRE

Kontinen, Noora

2016-01-01

Tutkin opinnäytetyössäni brändin ja musiikkivideon suhdetta toisiinsa. Työssä käsitellään lyhyesti myös tähteyttä. Esittelen ensin vähän historiaa ja peruskäsitteitä, minkä jälkeen käytän Michael Jacksonin Billie Jean -musiikkivideota esimerkkinä tutkiessani Michael Jacksonin brändiä. Teoksessa käytetään lähdeaineistoa sekä omaa analyysia. Keskityn tarkastelemaan musiikkivideoita, ja niihin liittyviä sisältöjä yleisesti, ei niinkään teknisesti. Toivon, että työstäni on apua jollekin,...

Michael Goodsite gæsteprofessor på Thunderbird School of Global Management

DEFF Research Database (Denmark)

Pedersen, Jens Christian

2010-01-01

Professor Michael Goodsite er blevet udnævnt til "Visiting Professor of Global Processes and Senior Research Fellow in Climate Strategy" ved Thunderbird School of Global Management, som har verdens højst rangerede MBA uddannelse inden for international handel.......Professor Michael Goodsite er blevet udnævnt til "Visiting Professor of Global Processes and Senior Research Fellow in Climate Strategy" ved Thunderbird School of Global Management, som har verdens højst rangerede MBA uddannelse inden for international handel....

Correspondence of Michael Faraday, v.5 1855-1860

CERN Document Server

Faraday, Michael

2008-01-01

This volume includes 70% of previously unpublished letters of Michael Farday spanning half of the 1850s and most of 1860. Topics include Faraday's work on regelation, the transmission of light through gold and his appointment by Emperor Napoleon III to be a Commander of the Legion of Honour.

Cauchy horizons in Gowdy spacetimes

International Nuclear Information System (INIS)

Chrusciel, Piotr T; Lake, Kayll

2004-01-01

We analyse exhaustively the structure of non-degenerate Cauchy horizons in Gowdy spacetimes, and we establish existence of a large class of non-polarized Gowdy spacetimes with such horizons. Our results here, together with the deep new results of Ringstroem, establish strong cosmic censorship in (toroidal) Gowdy spacetimes

Michael Jackson antes del caos

OpenAIRE

Juan Luciano Nieves

2015-01-01

Michael Jackson es un buen ejemplo de cómo utilizar las relaciones públicas para realizar o manipular la imagen de un producto a través de los medios de comunicación. Este ensayo pretende analizar los eventos que tuvieron lugar antes de que el cantante fuera acusado de abuso sexual contra un menor. Dichos eventos formaron parte de un plan muy bien delineado para disminuir los efectos de la inminente crisis que se acercaba. Este trabajo combina la crítica retórica de temas de fantasía con teor...

Horizon shells and BMS-like soldering transformations

Energy Technology Data Exchange (ETDEWEB)

Blau, Matthias [Albert Einstein Center for Fundamental Physics,Institute for Theoretical Physics, University of Bern,Sidlerstrasse 5, 3012 Bern (Switzerland); O’Loughlin, Martin [University of Nova Gorica,Vipavska 13, 5000 Nova Gorica (Slovenia)

2016-03-07

We revisit the theory of null shells in general relativity, with a particular emphasis on null shells placed at horizons of black holes. We study in detail the considerable freedom that is available in the case that one solders two metrics together across null hypersurfaces (such as Killing horizons) for which the induced metric is invariant under translations along the null generators. In this case the group of soldering transformations turns out to be infinite dimensional, and these solderings create non-trivial horizon shells containing both massless matter and impulsive gravitational wave components. We also rephrase this result in the language of Carrollian symmetry groups. To illustrate this phenomenon we discuss in detail the example of shells on the horizon of the Schwarzschild black hole (with equal interior and exterior mass), uncovering a rich classical structure at the horizon and deriving an explicit expression for the general horizon shell energy-momentum tensor. In the special case of BMS-like soldering supertranslations we find a conserved shell-energy that is strikingly similar to the standard expression for asymptotic BMS supertranslation charges, suggesting a direct relation between the physical properties of these horizon shells and the recently proposed BMS supertranslation hair of a black hole.

Super-horizon primordial black holes

International Nuclear Information System (INIS)

Harada, Tomohiro; Carr, B.J.

2005-01-01

We discuss a new class of solutions to the Einstein equations which describe a primordial black hole (PBH) in a flat Friedmann background. Such solutions arise if a Schwarzschild black hole is patched onto a Friedmann background via a transition region. They are possible providing the black hole event horizon is larger than the cosmological apparent horizon. Such solutions have a number of strange features. In particular, one has to define the black hole and cosmological horizons carefully and one then finds that the mass contained within the black hole event horizon decreases when the black hole is larger than the Friedmann cosmological apparent horizon, although its area always increases. These solutions involve two distinct future null infinities and are interpreted as the conversion of a white hole into a black hole. Although such solutions may not form from gravitational collapse in the same way as standard PBHs, there is nothing unphysical about them, since all energy and causality conditions are satisfied. Their conformal diagram is a natural amalgamation of the Kruskal diagram for the extended Schwarzschild solution and the conformal diagram for a black hole in a flat Friedmann background. In this paper, such solutions are obtained numerically for a spherically symmetric universe containing a massless scalar field, but it is likely that they exist for more general matter fields and less symmetric systems

Eesti luksushotellide ristiisa / Michael Stenner ; interv. Malle Koido

Index Scriptorium Estoniae

Stenner, Michael

2007-01-01

Eesti tipphotelle 1997. aastast juhtinud sakslane, praegu hotellide Kolm Õde ja Telegraaf juht räägib Eesti ja Saksamaa erinevustest, Eesti hotelliärist, teeninduskultuurist ja personalist. Lisa: Kes on Michael Stenner ning kuidas ta Eestisse sattus? Ilmunud ka: Linnaleht : Pärnu, 23. veebr. 2007, lk. 5-6

IUTAM Symposium on Innovative Numerical Approaches for Materials and Structures in Multi-Field and Multi-Scale Problems : in Honor of Michael Ortiz's 60th Birthday

CERN Document Server

Pandolfi, Anna

2016-01-01

This book provides readers with a detailed insight into diverse and exciting recent developments in computational solid mechanics, documenting new perspectives and horizons. The topics addressed cover a wide range of current research, from computational materials modeling, including crystal plasticity, micro-structured materials, and biomaterials, to multi-scale simulations of multi-physics phenomena. Particular emphasis is placed on pioneering discretization methods for the solution of coupled non-linear problems at different length scales. The book, written by leading experts, reflects the remarkable advances that have been made in the field over the past decade and more, largely due to the development of a sound mathematical background and efficient computational strategies. The contents build upon the 2014 IUTAM symposium celebrating the 60th birthday of Professor Michael Ortiz, to whom this book is dedicated. His work has long been recognized as pioneering and is a continuing source of inspiration for ma...

Dynamical symmetry enhancement near IIA horizons

International Nuclear Information System (INIS)

Gran, University; Gutowski, J.; Kayani, University; Papadopoulos, G.

2015-01-01

We show that smooth type IIA Killing horizons with compact spatial sections preserve an even number of supersymmetries, and that the symmetry algebra of horizons with non-trivial fluxes includes an sl(2,ℝ) subalgebra. This confirms the conjecture of http://dx.doi.org/10.1007/JHEP11(2013)104 for type IIA horizons. As an intermediate step in the proof, we also demonstrate new Lichnerowicz type theorems for spin bundle connections whose holonomy is contained in a general linear group.

Instability of enclosed horizons

Science.gov (United States)

Kay, Bernard S.

2015-03-01

We point out that there are solutions to the scalar wave equation on dimensional Minkowski space with finite energy tails which, if they reflect off a uniformly accelerated mirror due to (say) Dirichlet boundary conditions on it, develop an infinite stress-energy tensor on the mirror's Rindler horizon. We also show that, in the presence of an image mirror in the opposite Rindler wedge, suitable compactly supported arbitrarily small initial data on a suitable initial surface will develop an arbitrarily large stress-energy scalar near where the two horizons cross. Also, while there is a regular Hartle-Hawking-Israel-like state for the quantum theory between these two mirrors, there are coherent states built on it for which there are similar singularities in the expectation value of the renormalized stress-energy tensor. We conjecture that in other situations with analogous enclosed horizons such as a (maximally extended) Schwarzschild black hole in equilibrium in a (stationary spherical) box or the (maximally extended) Schwarzschild-AdS spacetime, there will be similar stress-energy singularities and almost-singularities—leading to instability of the horizons when gravity is switched on and matter and gravity perturbations are allowed for. All this suggests it is incorrect to picture a black hole in equilibrium in a box or a Schwarzschild-AdS black hole as extending beyond the past and future horizons of a single Schwarzschild (/Schwarzschild-AdS) wedge. It would thus provide new evidence for 't Hooft's brick wall model while seeming to invalidate the picture in Maldacena's ` Eternal black holes in AdS'. It would thereby also support the validity of the author's matter-gravity entanglement hypothesis and of the paper ` Brick walls and AdS/CFT' by the author and Ortíz.

Horizons of hermeneutics: Intercultural hermeneutics in a globalizing world

NARCIS (Netherlands)

J. de Mul (Jos)

2011-01-01

textabstractStarting from the often-used metaphor of the "horizon of experience" this article discusses three different types of intercultural hermeneutics, which respectively conceive hermeneutic interpretation as a widening of horizons, a fusion of horizons, and a dissemination of horizons. It is

Hawking radiation from quasilocal dynamical horizons

Indian Academy of Sciences (India)

2016-01-06

Jan 6, 2016 ... Abstract. In completely local settings, we establish that a dynamically evolving spherically symmetric black hole horizon can be assigned a Hawking temperature and with the emission of flux, radius of the horizon shrinks.

Across-horizon scattering and information transfer

Science.gov (United States)

Emelyanov, V. A.; Klinkhamer, F. R.

2018-06-01

We address the question whether or not two electrically charged elementary particles can Coulomb scatter if one of these particles is inside the Schwarzschild black-hole horizon and the other outside. It can be shown that the quantum process is consistent with the local energy–momentum conservation law. This result implies that across-horizon scattering is a physical effect, relevant to astrophysical black holes. We propose a Gedankenexperiment which uses the quantum scattering process to transfer information from inside the black-hole horizon to outside.

Tropospheric radiowave propagation beyond the horizon

CERN Document Server

Du Castel, François

1966-01-01

Tropospheric Radiowave Propagation Beyond the Horizon deals with developments concerning the tropospheric propagation of ultra-short radio waves beyond the horizon, with emphasis on the relationship between the theoretical and the experimental. Topics covered include the general conditions of propagation in the troposphere; general characteristics of propagation beyond the horizon; and attenuation in propagation. This volume is comprised of six chapters and begins with a brief historical look at the various stages that have brought the technique of transhorizon links to its state of developmen

Mastering VMware Horizon 6

CERN Document Server

Oven, Peter von

2015-01-01

If you are working as a desktop admin, part of a EUC team, an architect, or a consultant on a desktop virtualization project and you are looking to use VMware's Horizon solution, this book is for you. This book will demonstrate the new capabilities of Horizon 6. You should have experience in desktop management using Windows and Microsoft Office, and be familiar with Active Directory, SQL, Windows Remote Desktop Session Hosting, and VMware vSphere infrastructure (ESXi and vCenter Server) technology.

Berliinis võidutses Michael Haneke / Jüri Laulik

Index Scriptorium Estoniae

Laulik, Jüri, 1959-

2005-01-01

IX PÖFFil linastuv Michael Haneke film "Varjatud" ("Cache") võitis laupäeval mitu Euroopa Filmiakadeemia auhinda, sealhulgas parima filmi, parima lavastaja ja parima meesnäitleja (Daniel Auteuil) auhinna. Parima naisnäitleja tiitli pälvis Julia Jentsch ("Sophie Scholli viimased päevad"). Elutööpreemia sai sir Sean Connery

Michael Jackson antes del caos

Directory of Open Access Journals (Sweden)

Juan Luciano Nieves

2015-01-01

Full Text Available Michael Jackson es un buen ejemplo de cómo utilizar las relaciones públicas para realizar o manipular la imagen de un producto a través de los medios de comunicación. Este ensayo pretende analizar los eventos que tuvieron lugar antes de que el cantante fuera acusado de abuso sexual contra un menor. Dichos eventos formaron parte de un plan muy bien delineado para disminuir los efectos de la inminente crisis que se acercaba. Este trabajo combina la crítica retórica de temas de fantasía con teoría de comunicación.

Horizon 2020 in sight

CERN Multimedia

Joannah Caborn Wengler

2012-01-01

Every tenth member of the CERN personnel participates in an EU-funded project – a strong indication of CERN’s successful relations with the European Commission (EC), coordinated by the CERN EU projects office. The EC director in charge of preparing “Horizon 2020”, the new EU funding programme for research and innovation (2014-2020), will be giving a presentation at CERN on 8 May. He will reveal more about what the new programme has in store.   “It’s a very interesting time in the development of Horizon 2020, which is focusing the attention of all research communities in Europe,” explains Svetlomir Stavrev, head of the EU projects office. “After a long public consultation and drafting process, the Horizon 2020 proposal documents are now being reviewed by the European Parliament and Council.” CERN already participated in the consultation, making good use of the opportunity to contribute to the shaping of wh...

A perspectiva de Michael Apple para os estudos das políticas educacionais

Directory of Open Access Journals (Sweden)

Luís Armando Gandin

Full Text Available Resumo Este artigo tem como objetivo analisar as contribuições de Michael Apple para o campo da pesquisa em políticas educacionais. Na extensa obra de Michael Apple, destacamos seis elementos que podem auxiliar aqueles que estão interessados na área de políticas em educação: o princípio epistemológico da análise relacional; o exame do Estado como relação; a herança de Antonio Gramsci e de Raymond Williams que Michael Apple incorpora no uso de conceitos como hegemonia e senso comum; a análise que Michael Apple faz das políticas educacionais como políticas culturais, como disputas por visão de mundo, como luta por consolidação de uma hegemonia que vai além do econômico; a sua postura de pesquisador; e a capacidade que Michael Apple tem de ir além da lógica da reprodução e determinação para enfatizar o papel da agência e da contra-hegemonia. Através de exemplos práticos da própria obra de Apple e de outras pesquisas empíricas, apresentam-se as implicações de cada um dos seis pontos acima citados para os pesquisadores interessados na área de políticas educacionais. Conclui-se que muitas das contribuições de Apple podem auxiliar em pesquisas nessa área, tendo em vista a discussão que o autor realiza em sua obra e sua crítica ao determinismo econômico nas análises do campo educacional, salientando a importância, assim, de aspectos que estão relacionados à esfera da cultura.

Implementing VMware Horizon View 5.2

CERN Document Server

Ventresco, Jason

2013-01-01

A step-by-step tutorial covering all components of the View Horizon suite in detail, to ensure that you can utilize all features of the platform, and discover all of the possible ways that it can be used within your own environment.If you are a newcomer in system administration, and you wish to implement a small to midsized Horizon View environment, then this book is for you. It will also benefit individuals who wish to administrate and manage Horizon View more efficiently or are studying for the VCP5-DT.

Review of the OSHA-NIOSH Response to the Deepwater Horizon Oil Spill: Protecting the Health and Safety of Cleanup Workers.

Science.gov (United States)

Michaels, David; Howard, John

2012-07-18

The fire and explosion of the Deepwater Horizon oil rig resulted in an enormous oil spill that threatened large distances of coastline. The overall response was led by the United States Coast Guard and involved the oil company BP, federal agencies, and state and local governments of five states. The Occupational Safety and Health Administration and the National Institute for Occupational Safety and Health focused extensive resources on ensuring that BP and its contractors provided safe working conditions for thousands of workers involved in the response. Federal personnel visited worksites daily, identifying hazards and means of abatement; assessed training programs to ensure that workers were adequately trained in languages they could understand; monitored chemical exposures and determined that the proper personal protective equipment was deployed; insisted on implementation of a heat mitigation program; rostered thousands of workers; and conducted extensive outreach in communities impacted by the spill. Advance planning, immediate deployment, and collaboration across agencies helped ensure that the response operations resulted in no worker fatalities, and relatively few injuries and illnesses. For future responses, improvements should be made in how safety and health information, as well as the process behind safety and health decisions, are communicated to the public. Michaels D, Howard J. Review of the OSHA-NIOSH Response to the Deepwater Horizon Oil Spill: Protecting the Health and Safety of Cleanup Workers. PLoS Currents Disasters. 2012 Jul 18.

Classification of Near-Horizon Geometries of Extremal Black Holes

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Hari K. Kunduri

2013-09-01

Full Text Available Any spacetime containing a degenerate Killing horizon, such as an extremal black hole, possesses a well-defined notion of a near-horizon geometry. We review such near-horizon geometry solutions in a variety of dimensions and theories in a unified manner. We discuss various general results including horizon topology and near-horizon symmetry enhancement. We also discuss the status of the classification of near-horizon geometries in theories ranging from vacuum gravity to Einstein–Maxwell theory and supergravity theories. Finally, we discuss applications to the classification of extremal black holes and various related topics. Several new results are presented and open problems are highlighted throughout.

Classification of Near-Horizon Geometries of Extremal Black Holes.

Science.gov (United States)

Kunduri, Hari K; Lucietti, James

2013-01-01

Any spacetime containing a degenerate Killing horizon, such as an extremal black hole, possesses a well-defined notion of a near-horizon geometry. We review such near-horizon geometry solutions in a variety of dimensions and theories in a unified manner. We discuss various general results including horizon topology and near-horizon symmetry enhancement. We also discuss the status of the classification of near-horizon geometries in theories ranging from vacuum gravity to Einstein-Maxwell theory and supergravity theories. Finally, we discuss applications to the classification of extremal black holes and various related topics. Several new results are presented and open problems are highlighted throughout.

DNA-based catalytic enantioselective intermolecular oxa-Michael addition reactions

NARCIS (Netherlands)

Megens, Rik P.; Roelfes, Gerard

2012-01-01

Using the DNA-based catalysis concept, a novel Cu(II) catalyzed enantioselective oxa-Michael addition of alcohols to enones is reported. Enantioselectivities of up to 86% were obtained. The presence of water is important for the reactivity, possibly by reverting unwanted side reactions such as

Moving Horizon Estimation and Control

DEFF Research Database (Denmark)

Jørgensen, John Bagterp

successful and applied methodology beyond PID-control for control of industrial processes. The main contribution of this thesis is introduction and definition of the extended linear quadratic optimal control problem for solution of numerical problems arising in moving horizon estimation and control...... problems. Chapter 1 motivates moving horizon estimation and control as a paradigm for control of industrial processes. It introduces the extended linear quadratic control problem and discusses its central role in moving horizon estimation and control. Introduction, application and efficient solution....... It provides an algorithm for computation of the maximal output admissible set for linear model predictive control. Appendix D provides results concerning linear regression. Appendix E discuss prediction error methods for identification of linear models tailored for model predictive control....

Michael Kohlhaas or the Germans and Their Law

Directory of Open Access Journals (Sweden)

Heike Jung

2014-12-01

Full Text Available Asked to pick a single representative ‘German’ piece for a discourse on ‘Law and Literature’ one almost inevitably ends up with Kleist’s tale Michael Kohlhaas. It seems to be the literary incarnation of the German stance vis-à-vis the law. It is all about horses; it could just as well be about dogs. Kohlhaas fights a devastating battle, using legal means and outright violence, even warfare, for their recovery in good shape. Victorious eventually with his legal actions, he is happy to trade in his own life for this victory, thus giving an extreme example for the nice line between being in the right and pursuing this position with disproportionate rigour. Of course, the interpretations of Michael Kohlhaas (which, in its complete version, dates of 1810 have varied from epoch to epoch as well as from reader to reader. It is not possible to rehearse the bulk of ‘Kohlhaas literature’. In comparing legal cultures, it might be of interest to look into the question why such a somber story on the law forms part and will continue to form part of the German cultural heritage. Si se tiene que elegir un único representante “alemán” para una ponencia sobre “derecho y literatura”, es inevitable optar por la obra de Kleist, Michael Kohlhaas. Parece la encarnación literaria de la posición alemana hacia el derecho. El libro trata de caballos; también podría tratar sobre perros. Kohlhaas libra una batalla devastadora usando medios legales y la violencia pura y dura, incluso la guerra, para que se recuperen en buena forma. Finalmente resulta ganador mediante acciones legales, está contento de dedicar su propia vida para conseguir esta victoria, dando así un ejemplo extremo de la línea que existe entre tener la razón y seguir esta posición con un rigor desproporcionado. Por supuesto, las interpretaciones de Michael Kohlhaas (publicado en 1810 han variado de una época a otra, y de un lector a otro. No es posible revisar el grueso de

77 FR 69550 - Proposed Information Collection (Patient Satisfaction Survey Michael E. DeBakey Home Care Program...

Science.gov (United States)

2012-11-19

... (Patient Satisfaction Survey Michael E. DeBakey Home Care Program) Activity: Comment Request AGENCY.... DeBakey Home Care Program. DATES: Written comments and recommendations on the proposed collection of...: Patient Satisfaction Survey Michael E. DeBakey Home Care Program, VA Form 10-0476. OMB Control Number...

76 FR 624 - Proposed Information Collection (Patient Satisfaction Survey Michael E. DeBakey Home Care Program...

Science.gov (United States)

2011-01-05

... Collection (Patient Satisfaction Survey Michael E. DeBakey Home Care Program) Activity: Comment Request... satisfaction with the quality of services/care provided by home care program staff. An agency may not conduct... Form 10-0476).'' SUPPLEMENTARY INFORMATION: Title: Patient Satisfaction Survey Michael E. DeBakey Home...

The conceptualization of love in religious thought of George Florovsky and Michael Pomazansky

Directory of Open Access Journals (Sweden)

Pavenkov Oleg Vladimirovich

2015-04-01

Full Text Available The present article is concerned with the question of conceptualization of love in works of Fr. George Florovsky and Fr. Michael Pomazansky, Russian religious thinkers and theologists. We are studying the meaning and appropriacy of two words, ‘love’ (English and ‘любовь’ (Russian, that are the best to represent the agapelogical positive evaluation in Russian religious thought. Data for study was taken from ten different articles and extracts from books written by Fr. George Florovsky and Fr. Michael Pomazansky. On the basis of this analysis we develop semantic explications of words ‘love’ and ‘любовь’ as Christian spiritual concepts within the framework of theoretical approach of Natural Semantic Metalanguage (NSM. In summary we state that this article discusses, describes and determines some similarities and differences in understanding of concept ‘love’ in the affore-referenced works by Fr. George Florovsky and Fr. Michael Pomazansky.

Stretched horizons, quasiparticles, and quasinormal modes

International Nuclear Information System (INIS)

Iizuka, Norihiro; Kabat, Daniel; Lifschytz, Gilad; Lowe, David A.

2003-01-01

We propose that stretched horizons can be described in terms of a gas of noninteracting quasiparticles. The quasiparticles are unstable, with a lifetime set by the imaginary part of the lowest quasinormal mode frequency. If the horizon arises from an AdS-CFT style duality the quasiparticles are also the effective low-energy degrees of freedom of the finite-temperature CFT. We analyze a large class of models including Schwarzschild black holes, nonextremal Dp-branes, the rotating BTZ black hole and de Sitter space, and we comment on degenerate horizons. The quasiparticle description makes manifest the relationship between entropy and area

Arenethiolatecopper(I) complexes as homogeneous catalysts for Michael addition reactions

NARCIS (Netherlands)

Koten, G. van; Klaveren, M. van; Lambert, F.; Eijkelkamp, D.J.F.M.; Grove, D.M.

1994-01-01

Arenethiolatocopper(I) complexes are shown to be efficient homogeneous catalysts in Michael addition reactions of several Grignard reagents to acyclic enones; the addition products are formed with excellent chemoselectivity (>99%) and good enantioselectivity (76% e.e.).

Nonlinear optics of fibre event horizons.

Science.gov (United States)

Webb, Karen E; Erkintalo, Miro; Xu, Yiqing; Broderick, Neil G R; Dudley, John M; Genty, Goëry; Murdoch, Stuart G

2014-09-17

The nonlinear interaction of light in an optical fibre can mimic the physics at an event horizon. This analogue arises when a weak probe wave is unable to pass through an intense soliton, despite propagating at a different velocity. To date, these dynamics have been described in the time domain in terms of a soliton-induced refractive index barrier that modifies the velocity of the probe. Here we complete the physical description of fibre-optic event horizons by presenting a full frequency-domain description in terms of cascaded four-wave mixing between discrete single-frequency fields, and experimentally demonstrate signature frequency shifts using continuous wave lasers. Our description is confirmed by the remarkable agreement with experiments performed in the continuum limit, reached using ultrafast lasers. We anticipate that clarifying the description of fibre event horizons will significantly impact on the description of horizon dynamics and soliton interactions in photonics and other systems.

Michael Bloomberg ähvardab USA valimised "ära rikkuda" / Heiki Suurkask

Index Scriptorium Estoniae

Suurkask, Heiki, 1972-

2008-01-01

New Yorgi praegune linnapea Michael Bloomberg võib kolmanda kandidaadina sekkuda presidendikandidaatide valimiskampaaniasse, probleem on aga tema vähene tuntus. Lisa: Seni on riigipeakoha jaganud kaks suurparteid

Professor Porter ja tema viis konkurentsitegurit / Michael E Porter

Index Scriptorium Estoniae

Porter, Michael E

2008-01-01

Maailmas tuntud juhtimisguru Michael Porter viie konkurentsijõu teooriast ja selle rakendatavusest erinevates valdkondades. Lisad: Erinevused valdkondade kasumlikkuses; 5 määravat konkurentsijõudu; Investeeritud kapitali keskmine tasuvus; Mõnede USA tegevusvaldkondade kasumlikkus; Valdkonnaanalüüs praktikas; Valdkonna määratlemine; Valdkonnaanalüüsi sammud

Michael Polanyi on the Education and Knowledge of Scientists.

Science.gov (United States)

Jacobs, Struan

2000-01-01

Explains why teachers addressing the nature of science should know the work of Michael Polanyi. Outlines Polanyi's intellectual career and examines his ideas on the education of scientists, research, and knowledge. Polanyi presaged Kuhn, Feyerabend, and the constructivists, yet insisted that science produces true knowledge about reality. (Contains…

Chinese Middle Classes: Taiwan, Hong Kong, Macao and China. Edited by Hsin-Huang Michael Hsiao

DEFF Research Database (Denmark)

Brødsgaard, Kjeld Erik

2018-01-01

Book review of: Chinese Middle Classes:Taiwan, Hong Kong, Macao and China. Edited by Hsin-Huang Michael Hsiao. Abingdon: Routledge, 2014. Pp. 268. ISBN 10: 1138120847; ISBN 13: 978-1138120846......Book review of: Chinese Middle Classes:Taiwan, Hong Kong, Macao and China. Edited by Hsin-Huang Michael Hsiao. Abingdon: Routledge, 2014. Pp. 268. ISBN 10: 1138120847; ISBN 13: 978-1138120846...

Black holes or firewalls: A theory of horizons

Science.gov (United States)

Nomura, Yasunori; Varela, Jaime; Weinberg, Sean J.

2013-10-01

We present a quantum theory of black hole (and other) horizons, in which the standard assumptions of complementarity are preserved without contradicting information theoretic considerations. After the scrambling time, the quantum mechanical structure of a black hole becomes that of an eternal black hole at the microscopic level. In particular, the stretched horizon degrees of freedom and the states entangled with them can be mapped into the near-horizon modes in the two exterior regions of an eternal black hole, whose mass is taken to be that of the evolving black hole at each moment. Salient features arising from this picture include (i) the number of degrees of freedom needed to describe a black hole is eA/2lP2, where A is the area of the horizon; (ii) black hole states having smooth horizons, however, span only an eA/4lP2-dimensional subspace of the relevant eA/2lP2-dimensional Hilbert space; (iii) internal dynamics of the horizon is such that an infalling observer finds a smooth horizon with a probability of 1 if a state stays in this subspace. We identify the structure of local operators responsible for describing semiclassical physics in the exterior and interior spacetime regions and show that this structure avoids the arguments for firewalls—the horizon can keep being smooth throughout the evolution. We discuss the fate of infalling observers under various circumstances, especially when the observers manipulate degrees of freedom before entering the horizon, and we find that an observer can never see a firewall by making a measurement on early Hawking radiation. We also consider the presented framework from the viewpoint of an infalling reference frame and argue that Minkowski-like vacua are not unique. In particular, the number of true Minkowski vacua is infinite, although the label discriminating these vacua cannot be accessed in usual nongravitational quantum field theory. An application of the framework to de Sitter horizons is also discussed.

Pengaruh Tipografi pada Era Massimo Vignelli terhadap Tipografi Michael Bierut

Directory of Open Access Journals (Sweden)

Irwan Harnoko

2011-10-01

Full Text Available Massimo Vignelli is a senior graphic designer lived in New York, as a vocal modernism against post-modernism. His statement firmly opposing post-modernism in several occasions: interview in Helvetica the movie, typeradio, talkshow, and some articles in Looking Closer or AIGA Journal. Graphic design works of Massimo Vignelli reflected his characteristic, which is firmly choosing typeface. Typefaces of Vignelly are around 5 typefaces: Bodoni, Helvetica, Times Roman, Century, and Futura. The article uses formal analysis method. The writers collected materials about Michael Bierut, Massimo VIgnelli and Tibor Kalman from books and websites. The writers compare the typeface opinion of Massimo Vignelli (modernism designer, Michael Bierut designer (transition era designer from modernism to post-modernism, and Tibor Kalman (a designer in A Century of Graphic Design, as the influencer of Bierut’s betrayal over Vignelli. 

Tweeting Prayers and Communicating Grief over Michael Jackson Online

Science.gov (United States)

Sanderson, Jimmy; Cheong, Pauline Hope

2010-01-01

Death and bereavement are human experiences that new media helps facilitate alongside creating new social grief practices that occur online. This study investigated how people's postings and tweets facilitated the communication of grief after pop music icon Michael Jackson died. Drawing on past grief research, religion, and new media studies, a…

78 FR 6851 - Proposed Information Collection (Patient Satisfaction Survey Michael E. DeBakey Home Care Program...

Science.gov (United States)

2013-01-31

... (Patient Satisfaction Survey Michael E. DeBakey Home Care Program) Activity: Comment Request AGENCY... Satisfaction Survey Michael E. DeBakey Home Care Program, VA Form 10-0476. OMB Control Number: 2900-0775. Type... home care program staff. An agency may not conduct or sponsor, and a person is not required to respond...

Cemented Horizons and Hardpans in the Coastal Tablelands of Northeastern Brazil

Directory of Open Access Journals (Sweden)

João Bosco Vasconcellos Gomes

Full Text Available ABSTRACT Horizons with varying degrees of cementation are a common feature of the soils from the coastal tablelands of Northeastern Brazil. In most cases, these horizons are represented by the following subsurface horizons: fragipan, duripan, ortstein, and placic. The aims of this study were to analyze differences regarding the development and the degree of expression of cementation in soils from the coastal tablelands of Northeastern Brazil: Planossolo Háplico (p-SX, Espodossolo Humilúvico (p-EK, Espodossolo Ferrihumilúvico (p-ESK, and Argissolo Acinzentado (p-PAC pedons. The pedons studied displayed features related to drainage impediments. The cemented horizons from p-SX and p-EK had the same designation (Btgm, displaying a duric character that coincided with gleization features and are under podzolized horizons. In the p-ESK, the podzolization process is of such magnitude that it leads to the cementation of its own spodic horizons, which were both of the ortstein type (Bhsx and Bsm. In the p-PAC cementation is observed in two placic horizons and in the Btx/Bt horizon, as well as in the upper parts of the Bt/Btx horizon. Analysis of the micrographies from the cemented horizons showed predominance of a low porosity matrix. Such porosity is relatively greater in the horizons of “x” subscript than in the horizons with duric character. The Fe segregation lines were notable in the cemented horizons from p-EK and p-PAC, which corroborates the presence of placic horizons in such pedons. The preponderance of kaolinite in the clay fraction was widely verified in all the cemented horizons analyzed. Water immersion tests were the criteria adopted to define the duric character of the Btgm horizons from p-SX and p-EK, and in the Bsm horizon from the p-ESK. These tests were also used to confirm field morphology. In most cases, the maximum values of Fe, Al, and Si, determined by different extractions, occurred in positions overlaying the cemented

VMware Horizon Workspace essentials

CERN Document Server

von Oven, Peter; Lindberg, Joel

2014-01-01

This book uses a step-by-step approach to teach you how to design, deploy, and manage a Horizon Workspace based on real world experience. Written in an easy-to-follow style, this book explains the terminology in a clear and concise manner. Each feature is explained starting at a high level and then drilling down into the technical detail, using diagrams and screenshots.This book is perfect for IT administrators who want to deploy a solution to centrally manage access to corporate applications, data, and virtual desktops using Horizon Workspace. You need to have some experience in delivering BY

Microbiomes structure and diversity in different horizons of full soil profiles

Science.gov (United States)

Chernov, Timofey; Tkhakakhova, Azida; Zhelezova, Alena; Semenov, Mikhail; Kutovaya, Olga

2017-04-01

Topsoil is a most common object for soil metagenomic studies; sometimes soil profile is being formally split in layers by depth. However, Russian Soil Science School formulated the idea of soil profile as a complex of soil horizons, which can differ in their properties and genesis. In this research we analyzed 57 genetic soil horizons of 8 different soils from European part of Russia: Albeluvisol, Greyzemic Phaeozem, three Chermozems (different land use - till, fallow, wind-protecting tree line), Rhodic Cambisol, Haplic Kastanozem and Salic Solonetz (WRB classification). Sampling was performed from all genetic horizons in each soil profile starting from topsoil until subsoil. Total DNA was extracted and 16S rRNA sequencing was provided together with chemical analysis of soil (pH measurement, C and N contents, etc.). Structure and diversity of prokaryotic community are significantly different in those soil horizons, which chemical properties and processes of origin are contrasting with nearest horizons: Na-enriched horizon of Solonetz, eluvial horizon of Albeluvisol, plough pan of Agrochernozem. Actinobacteria were abundant in top horizons of soils in warm and dry climate, while Acidobacteria had the highest frequency in soils of moist and cold regions. Concerning Archaea, Thaumarchaeota prevailed in all studied soils. Their rate was higher in microbiomes of upper horizons of steppe soils and it was reducing with depth down the profile. Prokaryotic communities in Chernozems were clustered by soil horizons types: microbiomes of A (organic topsoil) and B (mineral) horizons formed non-overlapping clusters by principal component analysis, cluster formed by prokaryotic communities of transitional soil horizons (AB) take place between clusters of A and B horizons. Moreover, prokaryotic communities of A horizons differ from each other strongly, while microbiomes of B horizons formed a narrow small cluster. It must be explaned by more diverse conditions in upper A horizons

A Good Time: A Conversation with C. Michael Nelson

Science.gov (United States)

Zabel, Robert; Kaff, Marilyn; Teagarden, Jim

2015-01-01

C. Michael Nelson began his special education career as a teacher of adolescents with learning and behavior disorders. He has worked as a child psychologist and as a professor with the Department of Special Education and Rehabilitation Counseling at the University of Kentucky. He coordinated the graduate Personnel Preparation Program for Teachers…

Aza-Michael Reaction for an Undergraduate Organic Chemistry Laboratory

Science.gov (United States)

Nigam, Manisha; Rush, Brittney; Patel, Jay; Castillo, Raul; Dhar, Preeti

2016-01-01

A green, aza-Michael reaction is described that can be used to teach undergraduate students conjugate addition of nitrogen nucleophile to an a,ß-unsaturated ester. Students analyze spectral data of the product obtained from the assigned reaction to determine product structure and propose the mechanism of its formation. The experiment requires…

The influence of time horizon on results of cost-effectiveness analyses.

Science.gov (United States)

Kim, David D; Wilkinson, Colby L; Pope, Elle F; Chambers, James D; Cohen, Joshua T; Neumann, Peter J

2017-12-01

Debates persist on the appropriate time horizon from a payer's perspective and how the time horizon in cost-effectiveness analysis (CEA) influences the value assessment. We systematically reviewed the Tufts Medical Center CEA Registry and identified US-based studies that used a payer perspective from 2005-2014. We classified the identified CEAs as short-term (time horizon ≤ 5 years) and long-term (> 5 years), and examined associations between study characteristics and the specified time horizon. We also developed case studies with selected interventions to further explore the relationship between time horizon and projected costs, benefits, and incremental cost-effectiveness ratios (ICER). Among 782 identified studies that met our inclusion criteria, 552 studies (71%) utilized a long-term time horizon while 198 studies (25%) used a short-term horizon. Among studies that employed multiple time horizons, the extension of the time horizon yielded more favorable ICERs in 19 cases and less favorable ICERs in 4 cases. Case studies showed the use of a longer time horizon also yielded more favorable ICERs. The assumed time horizon in CEAs can substantially influence the value assessment of medical interventions. To capture all consequences, we encourage the use of time horizons that extend sufficiently into the future.

[An exceptional human relationship (Michael P. Kierkegaard, Søren Kierkegaard)].

Science.gov (United States)

Jacobs, R

1978-01-01

There were a father and a son, Michael and Sören Kierkegaard, both highly talented, imaginitive, witty, humorous, especially interested in shrewd dialectrical dialogues respectively debates, both profound melancholy ponderers. But according to very own individuality their congeniality wasn't absolute. The father, being under a questionable rigorous opinion of sin, suffered from undeserved divine grace since early childhood. And Michael Kierkegaard made Sören anxious with the religious experience of original sin. This anxiety moved (touched or affected) the sensitive son mighty. Nevertheless he should not despair hopelessly like his unlucky father. On the contrary: Sørens incomparable melancholy, mental agony and anxiety (fear or anguish) forced the faith, existing independently of them, in a radical refining. That is why Sören Kierkegaard succeeded in sublimation of all psychological and philosophic (al) attitudes (or opinions) in the sphere of religiousness. And the result? A novel philosophy of life: Christian existentialism.

Cosmological event horizons, thermodynamics, and particle creation

International Nuclear Information System (INIS)

Gibbons, G.W.; Hawking, S.W.

1977-01-01

It is shown that the close connection between event horizons and thermodynamics which has been found in the case of black holes can be extended to cosmological models with a repulsive cosmological constant. An observer in these models will have an event horizon whose area can be interpreted as the entropy or lack of information of the observer about the regions which he cannot see. Associated with the event horizon is a surface gravity kappa which enters a classical ''first law of event horizons'' in a manner similar to that in which temperature occurs in the first law of thermodynamics. It is shown that this similarity is more than an analogy: An observer with a particle detector will indeed observe a background of thermal radiation coming apparently from the cosmological event horizon. If the observer absorbs some of this radiation, he will gain energy and entropy at the expense of the region beyond his ken and the event horizon will shrink. The derivation of these results involves abandoning the idea that particles should be defined in an observer-independent manner. They also suggest that one has to use something like the Everett-Wheeler interpretation of quantum mechanics because the back reaction and hence the spacetime metric itself appear to be observer-dependent, if one assumes, as seems reasonable, that the detection of a particle is accompanied by a change in the gravitational field

Aza‐Michael addition reaction: Post‐polymerization modification and preparation of PEI/PEG‐based polyester hydrogels from enzymatically synthesized reactive polymers

DEFF Research Database (Denmark)

Hoffmann, Christian; Stuparu, Mihaiela C.; Daugaard, Anders Egede

2015-01-01

The utility of aza‐Michael addition chemistry for post‐polymerization functionalization of enzymatically prepared polyesters is established. For this, itaconate ester and oligoethylene glycol are selected as monomers. A Candida Antarctica lipase B catalyzed polycondensation reaction between the two...... monomers provides the polyesters, which carry an activated carbon‐carbon double bond in the polymer backbone. These electron deficient alkenes represent suitable aza‐Michael acceptors and can be engaged in a nucleophilic addition reaction with small molecular mono‐amines (aza‐Michael donors) to yield...... functionalized linear polyesters. Employing a poly‐amine as the aza‐Michael donor, on the other hand, results in the formation of hydrophilic polymer networks....

Horizon quantum mechanics of rotating black holes

Energy Technology Data Exchange (ETDEWEB)

Casadio, Roberto [Universita di Bologna, Dipartimento di Fisica e Astronomia, Bologna (Italy); I.N.F.N., Sezione di Bologna, I.S. FLAG, Bologna (Italy); Giugno, Andrea [Ludwig-Maximilians-Universitaet, Arnold Sommerfeld Center, Munich (Germany); Giusti, Andrea [Universita di Bologna, Dipartimento di Fisica e Astronomia, Bologna (Italy); I.N.F.N., Sezione di Bologna, I.S. FLAG, Bologna (Italy); Ludwig-Maximilians-Universitaet, Arnold Sommerfeld Center, Munich (Germany); Micu, Octavian [Institute of Space Science, Bucharest, P.O. Box MG-23, Bucharest-Magurele (Romania)

2017-05-15

The horizon quantum mechanics is an approach that was previously introduced in order to analyze the gravitational radius of spherically symmetric systems and compute the probability that a given quantum state is a black hole. In this work, we first extend the formalism to general space-times with asymptotic (ADM) mass and angular momentum. We then apply the extended horizon quantum mechanics to a harmonic model of rotating corpuscular black holes. We find that simple configurations of this model naturally suppress the appearance of the inner horizon and seem to disfavor extremal (macroscopic) geometries. (orig.)

Bootstrap, universality and horizons

Energy Technology Data Exchange (ETDEWEB)

Chang, Chi-Ming [Center for Theoretical Physics and Department of Physics,University of California, Berkeley, CA 94704 (United States); Lin, Ying-Hsuan [Jefferson Physical Laboratory, Harvard University,Cambridge, MA 02138 (United States)

2016-10-13

We present a closed form expression for the semiclassical OPE coefficients that are universal for all 2D CFTs with a “weak” light spectrum, by taking the semiclassical limit of the fusion kernel. We match this with a properly regularized and normalized bulk action evaluated on a geometry with three conical defects, analytically continued in the deficit angles beyond the range for which a metric with positive signature exists. The analytically continued geometry has a codimension-one coordinate singularity surrounding the heaviest conical defect. This singularity becomes a horizon after Wick rotating to Lorentzian signature, suggesting a connection between universality and the existence of a horizon.

Redshift of a photon emitted along the black hole horizon

Energy Technology Data Exchange (ETDEWEB)

Toporensky, A.V. [Lomonosov Moscow State University, Sternberg Astronomical Institute, Moscow (Russian Federation); Kazan Federal University, Kazan (Russian Federation); Zaslavskii, O.B. [Kazan Federal University, Kazan (Russian Federation); Kharkov V.N. Karazin National University, Department of Physics and Technology, Kharkov (Ukraine)

2017-03-15

In this work we derive some general features of the redshift measured by radially moving observers in the black hole background. Let observer 1 cross the black hole horizon emitting a photon, while observer 2 crossing the same horizon later receives it. We show that if (i) the horizon is the outer one (event horizon) and (ii) it is nonextremal, the received frequency is redshifted. This generalizes recent results in the literature. For the inner horizon (like in the Reissner-Nordstroem metric) the frequency is blueshifted. If the horizon is extremal, the frequency does not change. We derive explicit formulas describing the frequency shift in generalized Kruskal- and Lemaitre-like coordinates. (orig.)

Pricing Liquidity Risk with Heterogeneous Investment Horizons

NARCIS (Netherlands)

Beber, Alessandro; Driessen, Joost; Neuberger, A.; Tuijp, P

We develop an asset pricing model with stochastic transaction costs and investors with heterogeneous horizons. Depending on their horizon, investors hold different sets of assets in equilibrium. This generates segmentation and spillover effects for expected returns, where the liquidity (risk)

Reflection, radiation, and interference near the black hole horizon

International Nuclear Information System (INIS)

Kuchiev, M.Yu.

2004-01-01

The event horizon of black holes is capable of reflection: there is a finite probability for any particle that approaches the horizon to bounce back. The albedo of the horizon depends on the black hole temperature and the energy of the incoming particle. The reflection shares its physical origins with the Hawking process of radiation; both of them arise as consequences of the mixing of the incoming and outgoing waves that takes place due to quantum processes on the event horizon

Plasmonic Horizon in Gold Nanosponges.

Science.gov (United States)

Vidal, Cynthia; Sivun, Dmitry; Ziegler, Johannes; Wang, Dong; Schaaf, Peter; Hrelescu, Calin; Klar, Thomas A

2018-02-14

An electromagnetic wave impinging on a gold nanosponge coherently excites many electromagnetic hot-spots inside the nanosponge, yielding a polarization-dependent scattering spectrum. In contrast, a hole, recombining with an electron, can locally excite plasmonic hot-spots only within a horizon given by the lifetime of localized plasmons and the speed carrying the information that a plasmon has been created. This horizon is about 57 nm, decreasing with increasing size of the nanosponge. Consequently, photoluminescence from large gold nanosponges appears unpolarized.

Quantum-corrected geometry of horizon vicinity

Energy Technology Data Exchange (ETDEWEB)

Park, I.Y. [Department of Applied Mathematics, Philander Smith College, Little Rock, AR (United States)

2017-12-15

We study the deformation of the horizon-vicinity geometry caused by quantum gravitational effects. Departure from the semi-classical picture is noted, and the fact that the matter part of the action comes at a higher order in Newton's constant than does the Einstein-Hilbert term is crucial for the departure. The analysis leads to a Firewall-type energy measured by an infalling observer for which quantum generation of the cosmological constant is critical. The analysis seems to suggest that the Firewall should be a part of such deformation and that the information be stored both in the horizon-vicinity and asymptotic boundary region. We also examine the behavior near the cosmological horizon. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Quantum-corrected geometry of horizon vicinity

International Nuclear Information System (INIS)

Park, I.Y.

2017-01-01

We study the deformation of the horizon-vicinity geometry caused by quantum gravitational effects. Departure from the semi-classical picture is noted, and the fact that the matter part of the action comes at a higher order in Newton's constant than does the Einstein-Hilbert term is crucial for the departure. The analysis leads to a Firewall-type energy measured by an infalling observer for which quantum generation of the cosmological constant is critical. The analysis seems to suggest that the Firewall should be a part of such deformation and that the information be stored both in the horizon-vicinity and asymptotic boundary region. We also examine the behavior near the cosmological horizon. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

QFT holography near the horizon of Schwarzschild-like spacetimes

OpenAIRE

Moretti, Valter; Pinamonti, Nicola

2003-01-01

It is argued that free QFT can be defined on the event horizon of a Schwarzschild-like spacetime and that this theory is unitarily and algebraically equivalent to QFT in the bulk (near the horizon). Under that unitary equivalence the bulk hidden SL(2,R) symmetry found in a previous work becomes manifest on the event horizon, it being induced by a group of horizon diffeomorphisms. The class of generators of that group can be enlarged to include a full Virasoro algebra of fields which are defin...

New Models at Lasell: Q&A with President Michael Alexander

Science.gov (United States)

Harney, John O.

2018-01-01

The "New England Journal of Higher Education" ("NEJHE") Executive Editor John O. Harney had the chance to catch up with Lasell College President Michael Alexander about the small Newton, Massachusetts, college's plans to challenge the higher education business model. The interview is presented in this article.

Hydrological classification of orthic A horizons in Weatherley, South ...

African Journals Online (AJOL)

Orthic A horizons carry little interpretive, especially hydrological, value. This paper aims to elucidate the hydrological interpretation of orthic A horizons. Measured water contents in the orthic A horizons of 28 profiles in the Weatherley catchment of South Africa were used to classify the topsoils into wetness classes. The very ...

Competition, Time Horizon and Corporate Social Performance

NARCIS (Netherlands)

Graafland, J.J.; Smid, H.

2013-01-01

Abstract: This paper develops and tests a conceptual framework on the relationships between competition, time horizon and corporate social performance (CSP). We hypothesize that more intense competition discourages CSP by lowering the time horizon of companies. We test the hypothesis on a sample of

Maximal indecomposable past sets and event horizons

International Nuclear Information System (INIS)

Krolak, A.

1984-01-01

The existence of maximal indecomposable past sets MIPs is demonstrated using the Kuratowski-Zorn lemma. A criterion for the existence of an absolute event horizon in space-time is given in terms of MIPs and a relation to black hole event horizon is shown. (author)

"Alarme de incêndio": Michael Löwy e a crítica ecossocialista da civilização capitalista moderna "Fire alarm": Michael Löwy and the ecosocialist critique of the modern capitalist civilization

Directory of Open Access Journals (Sweden)

Fabio Mascaro Querido

2013-04-01

Full Text Available A emergência da crise ecológica, como sintoma mais nítido de uma verdadeira crise civilizató-ria, impôs novos desafios ao pensamento crítico e, em especial, ao marxismo. Partindo desse pressuposto, o objetivo deste artigo é apresentar a defesa de Michael Löwy de uma radicalização ecossocialista da crítica marxista da modernidade, tarefa para a qual a grande recusa de Walter Benjamin das ideologias do pro- gresso é uma das fontes decisivas de inspiração. Para Michael Löwy, a ruptura com as ideologias do progresso e com o paradigma civilizatório capitalista moderno é uma condição indispensável para a atua-lização ecossocialista do marxismo.The emergence of the ecological crisis as a clearer symptom of a true civilizatory crisis has imposed new challenges to critical thought and, in particular, to Marxism. Based on this assumption, this article aims to present Michael Löwy's defense of an ecosocialist radicalization of the Marxist critique of modernity, a task for which Walter Benjamin's great refusal of the ideologies of progress is one of the critical sources of inspiration. To Michael Löwy, breaking away from the ideologies of progress and from the modern capitalistic civilizatory paradigm is a prerequisite for the ecosocialist updating of Marxism.

N-Heterocyclic Carbene-Catalysed Diastereoselective Vinylogous Michael Addition Reaction of gamma-Substituted deconjugated Butenolides

KAUST Repository

Guo, Hao

2015-11-16

An efficient N-heterocyclic carbene (NHC)-catalysed vinylogous Michael addition of deconjugated butenolides was developed. In the presence of 5 mol% of the NHC catalyst, both γ-alkyl and aryl-substituted deconjugated butenolides undergo vinylogous Michael addition with various α, β-unsaturated ketones, esters, or nitriles to afford γ,γ-disubstituted butenolides containing adjacent quaternary and tertiary carbon centers in good to excellent yields with excellent diastereoselectivities. In this process, the free carbene is assumed to act as a strong Brønsted base to promote the conjugate addition.

N-Heterocyclic Carbene-Catalysed Diastereoselective Vinylogous Michael Addition Reaction of gamma-Substituted deconjugated Butenolides

KAUST Repository

Guo, Hao; Xing, Fen; Du, Guang-Fen; Huang, Kuo-Wei; Dai, Bin; He, Lin

2015-01-01

An efficient N-heterocyclic carbene (NHC)-catalysed vinylogous Michael addition of deconjugated butenolides was developed. In the presence of 5 mol% of the NHC catalyst, both γ-alkyl and aryl-substituted deconjugated butenolides undergo vinylogous Michael addition with various α, β-unsaturated ketones, esters, or nitriles to afford γ,γ-disubstituted butenolides containing adjacent quaternary and tertiary carbon centers in good to excellent yields with excellent diastereoselectivities. In this process, the free carbene is assumed to act as a strong Brønsted base to promote the conjugate addition.

Cosmological horizons as new examples of the membrane paradigm

International Nuclear Information System (INIS)

Wang, Tower

2015-01-01

In this paper we aim to provide new examples of the application and the generality of the membrane paradigm. The membrane paradigm is a formalism for studying the event horizon of black holes. After analyzing it with some technical details and realizing it in the Reissner–Nordström black hole, we apply the paradigm to cosmological horizons, first to the pure de Sitter horizon, and then to the trapping horizon of the Friedmann–Lemaître–Robertson–Walker Universe. In the latter case, the cosmological stretched horizon is oblique, thus the running of the renormalization parameter is nonzero in the timelike direction and gives a correction to the membrane pressure. In this paradigm, the cosmological equations come from continuity equations of the membrane fluid and the bulk fluid respectively. (paper)

The absence of horizon in black-hole formation

Energy Technology Data Exchange (ETDEWEB)

Ho, Pei-Ming, E-mail: pmho@phys.ntu.edu.tw

2016-08-15

With the back-reaction of Hawking radiation taken into consideration, the work of Kawai, Matsuo and Yokokura [1] has shown that, under a few assumptions, the collapse of matter does not lead to event horizon nor apparent horizon. In this paper, we relax their assumptions and elaborate on the space-time geometry of a generic collapsing body with spherical symmetry. The geometry outside the collapsing sphere is found to be approximated by the geometry outside the white-hole horizon, hence the collapsing matter remains outside the Schwarzschild radius. As particles in Hawking radiation are created in the vicinity of the collapsing matter, the information loss paradox is alleviated. Assuming that the collapsing body evaporates within finite time, there is no event horizon.

The absence of horizon in black-hole formation

Directory of Open Access Journals (Sweden)

Pei-Ming Ho

2016-08-01

Full Text Available With the back-reaction of Hawking radiation taken into consideration, the work of Kawai, Matsuo and Yokokura [1] has shown that, under a few assumptions, the collapse of matter does not lead to event horizon nor apparent horizon. In this paper, we relax their assumptions and elaborate on the space-time geometry of a generic collapsing body with spherical symmetry. The geometry outside the collapsing sphere is found to be approximated by the geometry outside the white-hole horizon, hence the collapsing matter remains outside the Schwarzschild radius. As particles in Hawking radiation are created in the vicinity of the collapsing matter, the information loss paradox is alleviated. Assuming that the collapsing body evaporates within finite time, there is no event horizon.

The absence of horizon in black-hole formation

International Nuclear Information System (INIS)

Ho, Pei-Ming

2016-01-01

With the back-reaction of Hawking radiation taken into consideration, the work of Kawai, Matsuo and Yokokura [1] has shown that, under a few assumptions, the collapse of matter does not lead to event horizon nor apparent horizon. In this paper, we relax their assumptions and elaborate on the space-time geometry of a generic collapsing body with spherical symmetry. The geometry outside the collapsing sphere is found to be approximated by the geometry outside the white-hole horizon, hence the collapsing matter remains outside the Schwarzschild radius. As particles in Hawking radiation are created in the vicinity of the collapsing matter, the information loss paradox is alleviated. Assuming that the collapsing body evaporates within finite time, there is no event horizon.

Beyond the veil: Inner horizon instability and holography

International Nuclear Information System (INIS)

Balasubramanian, Vijay; Levi, Thomas S.

2004-01-01

We show that scalar perturbations of the eternal, rotating Banados-Teitelboim-Zanelli (BTZ) black hole should lead to an instability of the inner (Cauchy) horizon, preserving strong cosmic censorship. Because of backscattering from the geometry, plane-wave modes have a divergent stress tensor at the event horizon, but suitable wave packets avoid this difficulty, and are dominated at late times by quasinormal behavior. The wave packets have cuts in the complexified coordinate plane that are controlled by requirements of continuity, single-valuedness, and positive energy. Due to a focusing effect, regular wave packets nevertheless have a divergent stress energy at the inner horizon, signaling an instability. We propose that this instability, which is localized behind the event horizon, is detected holographically as a breakdown in the semiclassical computation of dual conformal field theory (CFT) expectation values in which the analytic behavior of wave packets in the complexified coordinate plane plays an integral role. In the dual field theory, this is interpreted as an encoding of physics behind the horizon in the entanglement between otherwise independent CFTs

Signature for the absence of an event horizon

International Nuclear Information System (INIS)

Barbieri, James; Chapline, George

2012-01-01

One of the most celebrated predictions of general relativity is that compact astrophysical objects with masses greater than a few solar masses are surrounded by an event horizon where time stands still and communication from the interior to the exterior is cutoff. Despite profound theoretical reasons for doubting whether an event horizon is physically possible, no definitive test as to whether event horizons really exist has yet been proposed. In this Letter we propose an experimental signature for the non-existence of event horizons. In particular we point out that a sharp dip in the spectrum of π 0 decay gamma rays below 70 MeV coming from compact objects with masses exceeding a few solar masses would be definitive evidence that these objects have a physical surface and there is no event horizon. Observation of such gamma rays would also for the first time open an experimental window on physical processes at energies near to the Planck scale. The prospects for seeing the 70 MeV feature in the near future are briefly discussed.

Educational Implications of Michael Fishbane's "Sacred Attunement: A Jewish Theology"

Science.gov (United States)

Marom, Daniel

2008-01-01

This article posits Michael Fishbane's Judaic scholarship as a prime resource for Jewish education. The link between the two fields can be made through a translation of the theological underpinnings of Fishbane's insights into Judaism to educational purposes and practices. Initial work with Jewish educators on establishing this link encouraged…

Hawking radiation of an apparent horizon in a FRW universe

International Nuclear Information System (INIS)

Cai Ronggen; Cao Liming; Hu Yapeng

2009-01-01

Hawking radiation is an important quantum phenomenon of a black hole, which is closely related to the existence of an event horizon of a black hole. The cosmological event horizon of de Sitter space is also of Hawking radiation with a thermal spectrum. By use of the tunneling approach, we show that there is indeed a Hawking radiation with temperature, T=1/(2πr-tilde A , for a locally defined apparent horizon of a Friedmann-Robertson-Walker universe with any spatial curvature, where r-tilde A is the apparent horizon radius. Thus we fill in the gap existing in the literature investigating the relation between the first law of thermodynamics and Friedmann equations; there the apparent horizon is assumed to have such a temperature without any proof. In addition, we stress the implication of the Hawking temperature associated with the apparent horizon.

Black hole entropy, universality, and horizon constraints

International Nuclear Information System (INIS)

Carlip, Steven

2006-01-01

To ask a question about a black hole in quantum gravity, one must restrict initial or boundary data to ensure that a black hole is actually present. For two-dimensional dilaton gravity, and probably a much wider class of theories, I show that the imposition of a 'stretched horizon' constraint modifies the algebra of symmetries at the horizon, allowing the use of conformal field theory techniques to determine the asymptotic density of states. The result reproduces the Bekenstein-Hawking entropy without any need for detailed assumptions about the microscopic theory. Horizon symmetries may thus offer an answer to the problem of universality of black hole entropy

Black hole entropy, universality, and horizon constraints

Energy Technology Data Exchange (ETDEWEB)

Carlip, Steven [Department of Physics, University of California, Davis, CA 95616 (United States)

2006-03-01

To ask a question about a black hole in quantum gravity, one must restrict initial or boundary data to ensure that a black hole is actually present. For two-dimensional dilaton gravity, and probably a much wider class of theories, I show that the imposition of a 'stretched horizon' constraint modifies the algebra of symmetries at the horizon, allowing the use of conformal field theory techniques to determine the asymptotic density of states. The result reproduces the Bekenstein-Hawking entropy without any need for detailed assumptions about the microscopic theory. Horizon symmetries may thus offer an answer to the problem of universality of black hole entropy.

The NMC Horizon Report: 2015 Museum Edition

Science.gov (United States)

Johnson, L.; Adams Becker, S.; Estrada, V.; Freeman, A.

2015-01-01

The internationally recognized series of "Horizon Reports" is part of the New Media Consortium's Horizon Project, a comprehensive research venture established in 2002 that identifies and describes emerging technologies likely to have a large impact over the coming years on a variety of sectors around the globe. This "2015 Horizon…

Fermions tunneling from apparent horizon of FRW universe

International Nuclear Information System (INIS)

Li Ran; Ren Jirong; Shi Dunfu

2009-01-01

In the paper [R.-G. Cai, L.-M. Cao, Y.-P. Hu, (arXiv: 0809.1554)], the scalar particles' Hawking radiation from the apparent horizon of Friedmann-Robertson-Walker (FRW) universe was investigated by using the tunneling formalism. They obtained the Hawking temperature associated with the apparent horizon, which was extensively applied in investigating the relationship between the first law of thermodynamics and Friedmann equations. In this Letter, we calculate fermions' Hawking radiation from the apparent horizon of FRW universe via tunneling formalism. Applying WKB approximation to the general covariant Dirac equation in FRW spacetime background, the radiation spectrum and Hawking temperature of apparent horizon are correctly recovered, which supports the arguments presented in the paper [R.-G. Cai, L.-M. Cao, Y.-P. Hu, (arXiv: 0809.1554)

Falling through the black hole horizon

International Nuclear Information System (INIS)

Brustein, Ram; Medved, A.J.M.

2015-01-01

We consider the fate of a small classical object, a “stick”, as it falls through the horizon of a large black hole (BH). Classically, the equivalence principle dictates that the stick is affected by small tidal forces, and Hawking’s quantum-mechanical model of BH evaporation makes essentially the same prediction. If, on the other hand, the BH horizon is surrounded by a “firewall”, the stick will be consumed as it falls through. We have recently extended Hawking’s model by taking into account the quantum fluctuations of the geometry and the classical back-reaction of the emitted particles. Here, we calculate the strain exerted on the falling stick for our model. The strain depends on the near-horizon state of the Hawking pairs. We find that, after the Page time when the state of the pairs deviates significantly from maximal entanglement (as required by unitarity), the induced strain in our semiclassical model is still parametrically small. This is because the number of the disentangled pairs is parametrically smaller than the BH entropy. A firewall does, however, appear if the number of disentangled pairs near the horizon is of order of the BH entropy, as implicitly assumed in previous discussions in the literature.

Locating the Gribov horizon

Energy Technology Data Exchange (ETDEWEB)

Gao, Fei; Qin, Si-Xue; Roberts, Craig D.; Rodríguez-Quintero, Jose

2018-02-01

We explore whether a tree-level expression for the gluon two-point function, supposed to express effects of an horizon term introduced to eliminate the Gribov ambiguity, is consistent with the propagator obtained in simulations of lattice-regularised quantum chromodynamics (QCD). In doing so, we insist that the gluon two-point function obey constraints that ensure a minimal level of consistency with parton-like behaviour at ultraviolet momenta. In consequence, we are led to a position which supports a conjecture that the gluon mass and horizon scale are equivalent emergent massscales, each with a value of roughly 0.5 GeV; and wherefrom it appears plausible that the dynamical generation of a running gluon mass may alone be sufficient to remove the Gribov ambiguity.

Locating the Gribov horizon

Science.gov (United States)

Gao, Fei; Qin, Si-Xue; Roberts, Craig D.; Rodríguez-Quintero, Jose

2018-02-01

We explore whether a tree-level expression for the gluon two-point function, supposed to express effects of an horizon term introduced to eliminate the Gribov ambiguity, is consistent with the propagator obtained in simulations of lattice-regularized quantum chromodynamics (QCD). In doing so, we insist that the gluon two-point function obey constraints that ensure a minimal level of consistency with parton-like behavior on the ultraviolet domain. In consequence, we are led to a position which supports a conjecture that the gluon mass and horizon scale are equivalent emergent mass-scales, each with a value of roughly 0.5 GeV; and wherefrom it appears plausible that the dynamical generation of a running gluon mass may alone be sufficient to remove the Gribov ambiguity.

77 FR 30047 - Notice of Opportunity for Public Comment on Surplus Property Release at Michael J Smith Field...

Science.gov (United States)

2012-05-21

... Comment on Surplus Property Release at Michael J Smith Field, Beaufort, NC AGENCY: Federal Aviation... J Smith Field, be used for aeronautical purposes. DATES: Comments must be received on or before June... property at the Michael J Smith Field. The property consists of one parcel located on the north side of...

Deepwater Horizon Seafood Safety Response - Deepwater Horizon Oil Spill Seafood Safety Response

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — In the aftermath of the Deepwater Horizon oil spill in 2010, there was concern about the risk to human health through consumption of contaminated seafood from the...

Membrane viewpoint on black holes: Dynamical electromagnetic fields near the horizon

International Nuclear Information System (INIS)

Macdonald, D.A.; Suen, W.

1985-01-01

This paper is part of a series of papers with the aim of developing a complete self-consistent formalism for the treatment of electromagnetic and gravitational fields in the neighborhood of a black-hole horizon. In this membrane formalism, the horizon is treated as a closed two-dimensional membrane lying in a curved three-dimensional space, and endowed with familiar physical properties such as entropy and temperature, surface pressure and viscosity, and electrical conductivity, charge, and current. This paper develops the concept of the ''stretched horizon,'' which will be vital for both the electromagnetic and gravitational aspects of the formalism, and it presents several model problems illustrating the interaction of dynamical electromagnetic fields with stationary black-hole horizons: The field of a test charge in various states of motion outside the Schwarzschild horizon is analyzed in the near-horizon limit, where the spatial curvature may be ignored and the metric may be approximated by that of Rindler. This analysis elucidates the influence of the horizon on the shapes and motions of electric and magnetic field lines when external agents move the field lines in arbitrary manners. It also illustrates how the field lines interact with the horizon's charge and current to produce an exchange of energy and momentum between the external agent and the horizon. A numerical calculation of the dynamical relaxation of a magnetic field threading a Schwarzschild black hole is also presented, illustrating the ''cleaning'' of a complicated field structure by a black-hole horizon, and elucidating the constraints on the location of the stretched horizon

Michael Perelman: An ecological future in view of Marxist Economics (Ⅱ)

Institute of Scientific and Technical Information of China (English)

Ren Xiaomei

2009-01-01

@@ Interviewee profile: Michael Perelman, currently professor of Economics Department of California State University, USA, American economist and economic historian with nearly 20 publications in the field of economics criticism, including Railroading Economics, Manufacturing Discontent, The Perverse Economy, and The Invention of Capitalism.

Michael Faraday on the Learning of Science and Attitudes of Mind.

Science.gov (United States)

Crawford, Elspeth

1998-01-01

Makes use of Michael Faraday's ideas on learning, focusing on his attitudes toward the unknowns of science and the development of an attitude that improves scientific decision making. This approach acknowledges that there is an inner struggle involved in facing unknowns. (DDR)

Hexafluorobenzene: A powerful solvent for a noncovalent stereoselective organocatalytic Michael addition reaction

KAUST Repository

Lattanzi, Alessandra; De Fusco, Claudia; Russo, Alessio; Poater, Albert; Cavallo, Luigi

2012-01-01

A dramatic enhancement of the diastereo- and enantioselectivity in the nitro-Michael addition reaction organocatalysed by a commercially available α,α-l-diaryl prolinol was disclosed when performing the reaction in unconventional hexafluorobenzene

Prints Charles ja prints Michael külastasid Tallinna kirikuid / Allan Tammiku

Index Scriptorium Estoniae

Tammiku, Allan

2001-01-01

Prints Charles külastas 6. novembril Eesti-visiidi ajal Tallinna toomkirikut ja Pühavaimu kirikut, prints Michael viibis Tallinnas 11. novembril eravisiidil, ta külastas toomkirikut, Niguliste ja Pühavaimu kirikut

Hawking radiation from the cosmological horizon in a FRW universe

International Nuclear Information System (INIS)

Hu Yapeng

2011-01-01

It is well known that there is a Hawking radiation from the cosmological horizon of the de Sitter spacetime, and the de Sitter spacetime can be a special case of a FRW universe. Therefore, there may be a corresponding Hawking radiation in a FRW universe. Indeed, there have been several clues showing that there is a Hawking radiation from the apparent horizon of a FRW universe. In our Letter, however, we find that the Hawking radiation may come from the cosmological horizon. Moreover, we also find that the Hawking radiation from the apparent horizon of a FRW universe in some previous works can be a special case in our result, and the condition is that the variation rate of cosmological horizon r . H is zero. Note that, this condition is also consistent with the underlying integrable condition in these works from the apparent horizon.

The pedogeochemical segregation a few horizons in soils from glass houses

Science.gov (United States)

Bulgariu, Dumitru; Rusu, Constantin; Filipov, Feodor; Buzgar, Nicolae; Bulgariu, Laura

2010-05-01

Our studies have focused the apparition and manifestation conditions of pedogeochemical segregation phenomena in case of soils from Copou - Iaşi, Bacău and Bârlad (Romania) glass house, and the effects of this on the pedogeochemical and agrochemical characteristics of soils from glass houses cultivated with vegetables. The utilization of intensive cultivation technologies of vegetables in glass houses determined the degradation of morphological, physical and chemical characteristics of soils, by rapid evolution of salted processes (salinization and / or sodization), compaction, carbonatation, eluviation-illuviation, frangipane formation, stagnogleization, gleization etc. Under these conditions, at depth of 30-40 cm is formed a compact and impenetrable horizon - Ahok(x) horizon. In function of exploitation conditions and by the chemical-mineralogical characteristics of soils from glasshouses, the Ahok horizons can have frangipane properties, expressed more or less. These horizons determined a geochemical segregation of soils from glass houses: (i) superior horizons, above Ahok(x) horizon evolve in weak oxidative conditions, weak alkaline pH, higher salinity, humidity and temperature; (ii) inferior horizons, below Ahok(x) horizon evolve in weak reducing conditions weak acid pH, lower salinity, humidity and temperature. Concomitant with the development of Ahok(x) horizons, the rapid degradation of the properties of soils from glasshouses is observed. The aspects about the formation of frangipane horizon in soils from glasshouses are not yet sufficiently know. Whatever of the formation processes, the frangipane horizons determined a sever segregation in pedogeochemical evolution of soils from glass houses, with very important consequences on the agrochemical quality of these soils. The segregation effects are manifested in the differential dynamics of pedogeochemical processes from superior horizons (situated above the segregation horizon), in comparison with the

Subjective Life Horizon and Portfolio Choice

OpenAIRE

Spaenjers , Christophe; Spira, Sven Michael

2013-01-01

Using data from a U.S. household survey, we examine the empirical relation between subjective life horizon (i.e., the self-reported expectation of remaining life span) and portfolio choice. We find that equity portfolio shares are higher for investors with longer horizons, ceteris paribus, in line with theoretical predictions. This result is robust to controlling for optimism and health status, accounting for the endogeneity of equity market participation, or instrumenting subjective life hor...

Der Wert von Worten. Michael Serrer aus dem Literaturbüro Düsseldorf im Interview mit der Textpraxis-Redaktion

Directory of Open Access Journals (Sweden)

Michael Serrer

2014-11-01

Full Text Available Die Textpraxis-Redaktion unterhält sich mit Michael Serrer über Literaturvermittlung in Zeiten der Digitalisierung, über Kanonisierung und die Rolle der Literatur in der Gesellschaft. Michael Serrer ist Leiter des Literaturbüros NRW und Feuilletonist.

Null infinity and extremal horizons in AdS-CFT

International Nuclear Information System (INIS)

Hickling, Andrew; Wiseman, Toby; Lucietti, James

2015-01-01

We consider AdS gravity duals to CFT on background spacetimes with a null infinity. Null infinity on the conformal boundary may extend to an extremal horizon in the bulk. For example it does so for Poincaré–AdS, although does not for planar Schwarzschild–AdS. If null infinity does extend into an extremal horizon in the bulk, we show that the bulk near-horizon geometry is determined by the geometry of the boundary null infinity. Hence the ‘infra-red’ geometry of the bulk is fixed by the large scale behaviour of the CFT spacetime. In addition the boundary stress tensor must have a particular decay at null infinity. As an application, we argue that for CFT on asymptotically flat backgrounds, any static bulk dual containing an extremal horizon extending from the boundary null infinity, must have the near-horizon geometry of Poincaré–AdS. We also discuss a class of boundary null infinity that cannot extend to a bulk extremal horizon, although we give evidence that they can extend to an analogous null surface in the bulk which possesses an associated scale-invariant ‘near-geometry’. (paper)

On the membrane paradigm and spontaneous breaking of horizon BMS symmetries

International Nuclear Information System (INIS)

Eling, Christopher; Oz, Yaron

2016-01-01

We consider a BMS-type symmetry action on isolated horizons in asymptotically flat spacetimes. From the viewpoint of the non-relativistic field theory on a horizon membrane, supertranslations shift the field theory spatial momentum. The latter is related by a Ward identity to the particle number symmetry current and is spontaneously broken. The corresponding Goldstone boson shifts the horizon angular momentum and can be detected quantum mechanically. Similarly, area preserving superrotations are spontaneously broken on the horizon membrane and we identify the corresponding gapless modes. In asymptotically AdS spacetimes we study the BMS-type symmetry action on the horizon in a holographic superfluid dual. We identify the horizon supertranslation Goldstone boson as the holographic superfluid Goldstone mode.

CFT/gravity correspondence on the isolated horizon

Energy Technology Data Exchange (ETDEWEB)

Ghosh, Amit, E-mail: amit.ghosh@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, 700064 Kolkata (India); Pranzetti, Daniele, E-mail: daniele.pranzetti@gravity.fau.de [Institute for Quantum Gravity, University of Erlangen-Nürnberg (FAU), Staudtstrasse 7/B2, 91058 Erlangen (Germany)

2014-12-15

A quantum isolated horizon can be modelled by an SU(2) Chern–Simons theory on a punctured 2-sphere. We show how a local 2-dimensional conformal symmetry arises at each puncture inducing an infinite set of new observables localised at the horizon which satisfy a Kac–Moody algebra. By means of the isolated horizon boundary conditions, we represent the gravitational flux degrees of freedom in terms of the zero modes of the Kac–Moody algebra defined on the boundary of a punctured disk. In this way, our construction encodes a precise notion of CFT/gravity correspondence. The higher modes in the algebra represent new nongeometric charges which can be represented in terms of free matter field degrees of freedom. When computing the CFT partition function of the system, these new states induce an extra degeneracy factor, representing the density of horizon states at a given energy level, which reproduces the Bekenstein's holographic bound for an imaginary Immirzi parameter. This allows us to recover the Bekenstein–Hawking entropy formula without the large quantum gravity corrections associated with the number of punctures.

Wider horizons, wiser choices: horizon scanning for public health protection and improvement.

Science.gov (United States)

Urquhart, Graham J; Saunders, Patrick

2017-06-01

Systematic continuous thinking about the future helps organizations, professions and communities to both prepare for, and shape, the future. This becomes ever more critical given the accelerating rate at which new data emerge, and in some cases uncertainties around their reliability and interpretation. Businesses with the capability to filter and analyse vast volumes of data to create knowledge and insights requiring action have a competitive advantage. Similarly Government and the public sector, including public health can be more effective and efficient through the early identification of emerging issues (both threats and opportunities). Horizon scanning approaches, and the use of resulting intelligence related to health protection and improvement were reviewed. Public health horizon scanning systems have to date focussed on health technologies and infectious diseases. While these have been successful there is a major gap in terms of non-infectious hazards and health improvement. Any system to meet this need must recognize the changed environment for delivering front line public health services and the critical role of local authorities and the local democratic process. This presents opportunities and challenges and this paper explores those dynamics describing an existing environment and health horizon scanning system which could readily and rapidly be re-engineered to provide a national service. © The Author 2016. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Universality of P−V criticality in horizon thermodynamics

Energy Technology Data Exchange (ETDEWEB)

Hansen, Devin; Kubizňák, David [Perimeter Institute,31 Caroline St. N., Waterloo, Ontario, N2L 2Y5 (Canada); Department of Physics and Astronomy, University of Waterloo,Waterloo, Ontario, N2L 3G1 (Canada); Mann, Robert B. [Department of Physics and Astronomy, University of Waterloo,Waterloo, Ontario, N2L 3G1 (Canada)

2017-01-11

We study P−V criticality of black holes in Lovelock gravities in the context of horizon thermodynamics. The corresponding first law of horizon thermodynamics emerges as one of the Einstein-Lovelock equations and assumes the universal (independent of matter content) form δE=TδS−PδV, where P is identified with the total pressure of all matter in the spacetime (including a cosmological constant Λ if present). We compare this approach to recent advances in extended phase space thermodynamics of asymptotically AdS black holes where the ‘standard’ first law of black hole thermodynamics is extended to include a pressure-volume term, where the pressure is entirely due to the (variable) cosmological constant. We show that both approaches are quite different in interpretation. Provided there is sufficient non-linearity in the gravitational sector, we find that horizon thermodynamics admits the same interesting black hole phase behaviour seen in the extended case, such as a Hawking-Page transition, Van der Waals like behaviour, and the presence of a triple point. We also formulate the Smarr formula in horizon thermodynamics and discuss the interpretation of the quantity E appearing in the horizon first law.

Universality of P−V criticality in horizon thermodynamics

International Nuclear Information System (INIS)

Hansen, Devin; Kubizňák, David; Mann, Robert B.

2017-01-01

We study P−V criticality of black holes in Lovelock gravities in the context of horizon thermodynamics. The corresponding first law of horizon thermodynamics emerges as one of the Einstein-Lovelock equations and assumes the universal (independent of matter content) form δE=TδS−PδV, where P is identified with the total pressure of all matter in the spacetime (including a cosmological constant Λ if present). We compare this approach to recent advances in extended phase space thermodynamics of asymptotically AdS black holes where the ‘standard’ first law of black hole thermodynamics is extended to include a pressure-volume term, where the pressure is entirely due to the (variable) cosmological constant. We show that both approaches are quite different in interpretation. Provided there is sufficient non-linearity in the gravitational sector, we find that horizon thermodynamics admits the same interesting black hole phase behaviour seen in the extended case, such as a Hawking-Page transition, Van der Waals like behaviour, and the presence of a triple point. We also formulate the Smarr formula in horizon thermodynamics and discuss the interpretation of the quantity E appearing in the horizon first law.

Receding Horizon H∞ Control for Input-Delayed Systems

Directory of Open Access Journals (Sweden)

Han Woong Yoo

2012-01-01

Full Text Available We propose the receding horizon H∞ control (RHHC for input-delayed systems. A new cost function for a finite horizon dynamic game problem is first introduced, which includes two terminal weighting terms parameterized by a positive definite matrix, called a terminal weighing matrix. Secondly, the RHHC is obtained from the solution to the finite dynamic game problem. Thirdly, we propose an LMI condition under which the saddle point value satisfies the nonincreasing monotonicity. Finally, we show the asymptotic stability and H∞ boundedness of the closed-loop system controlled by the proposed RHHC. The proposed RHHC has a guaranteed H∞ performance bound for nonzero external disturbances and the quadratic cost can be improved by adjusting the prediction horizon length for nonzero initial condition and zero disturbance, which is not the case for existing memoryless state-feedback controllers. It is shown through a numerical example that the proposed RHHC is stabilizing and satisfies the infinite horizon H∞ performance bound. Furthermore, the performance in terms of the quadratic cost is shown to be improved by adjusting the prediction horizon length when there exists no external disturbance with nonzero initial condition.

Passings to note: Paul Michael Packman, MD; S. Charles Schulz, MD.

Science.gov (United States)

Black, Donald W

2018-02-01

One of the keys to the success of Annals of Clinical Psychiatry has always been the tireless efforts of our dedicated Editorial Board. We recently lost 2 longtime Editorial Board members, Drs. Paul Michael Packman and S. Charles Schulz. Both will be greatly missed.

Reports of the working groups / Eino Tamm, Sahlin Michael, Valve Kirsipuu...[jt.

Index Scriptorium Estoniae

1999-01-01

Töögruppide "EU enlargement and relevant institutional reforms" (juhatajad Eino Tamm, Michael Sahlin) ja "Maintaining of competitiveness of Estonia and other candidate countries" (juhatajad Valve Kirsipuu, Terry Calbom) tööst. Autor: Reformierakond

Horizon thermodynamics in fourth-order gravity

Directory of Open Access Journals (Sweden)

Meng-Sen Ma

2017-03-01

Full Text Available In the framework of horizon thermodynamics, the field equations of Einstein gravity and some other second-order gravities can be rewritten as the thermodynamic identity: dE=TdS−PdV. However, in order to construct the horizon thermodynamics in higher-order gravity, we have to simplify the field equations firstly. In this paper, we study the fourth-order gravity and convert it to second-order gravity via a so-called “Legendre transformation” at the cost of introducing two other fields besides the metric field. With this simplified theory, we implement the conventional procedure in the construction of the horizon thermodynamics in 3 and 4 dimensional spacetime. We find that the field equations in the fourth-order gravity can also be written as the thermodynamic identity. Moreover, we can use this approach to derive the same black hole mass as that by other methods.

Thermal and nonthermal particle production without event horizons

International Nuclear Information System (INIS)

Sanchez, N.

1979-01-01

Usually, particle production in accelerated frames is discussed in connection with the presence of event horizons and with a planckian spectrum. Accelerated frames without event horizons, where particle production takes place with thermal as well as nonthermal distributions, are constructed. (Auth.)

Joseph and Michael Haydn in the Bohemian music archives. An anniversary tribute

Czech Academy of Sciences Publication Activity Database

Freemanová, Michaela

2012-01-01

Roč. 20, č. 1 (2012), s. 117-126. ISBN 978-3-486-58949-8. ISSN 1865-5696 Institutional support: RVO:68378076 Keywords : Joseph Haydn * Michael Haydn * music archives Subject RIV: AL - Art, Architecture, Cultural Heritage

Birth of plant proteomics in India: a new horizon.

Science.gov (United States)

Narula, Kanika; Pandey, Aarti; Gayali, Saurabh; Chakraborty, Niranjan; Chakraborty, Subhra

2015-09-08

In the post-genomic era, proteomics is acknowledged as the next frontier for biological research. Although India has a long and distinguished tradition in protein research, the initiation of proteomics studies was a new horizon. Protein research witnessed enormous progress in protein separation, high-resolution refinements, biochemical identification of the proteins, protein-protein interaction, and structure-function analysis. Plant proteomics research, in India, began its journey on investigation of the proteome profiling, complexity analysis, protein trafficking, and biochemical modeling. The research article by Bhushan et al. in 2006 marked the birth of the plant proteomics research in India. Since then plant proteomics studies expanded progressively and are now being carried out in various institutions spread across the country. The compilation presented here seeks to trace the history of development in the area during the past decade based on publications till date. In this review, we emphasize on outcomes of the field providing prospects on proteomic pathway analyses. Finally, we discuss the connotation of strategies and the potential that would provide the framework of plant proteome research. The past decades have seen rapidly growing number of sequenced plant genomes and associated genomic resources. To keep pace with this increasing body of data, India is in the provisional phase of proteomics research to develop a comparative hub for plant proteomes and protein families, but it requires a strong impetus from intellectuals, entrepreneurs, and government agencies. Here, we aim to provide an overview of past, present and future of Indian plant proteomics, which would serve as an evaluation platform for those seeking to incorporate proteomics into their research programs. This article is part of a Special Issue entitled: Proteomics in India. Copyright © 2015 Elsevier B.V. All rights reserved.

Entretien avec Michael Quinn Patton | CRDI - Centre de recherches ...

International Development Research Centre (IDRC) Digital Library (Canada)

9 févr. 2011 ... Michael Quinn Patton, évaluateur de renommée internationale, était récemment au CRDI .... C'est un mode de pensée analytique qui doit tout imprégner. ... des données solides et crédibles sur ce qui marche et ce qui ne marche pas. ... des emplois, des infrastructures et un accès à la nourriture et aux mar.

Hawking spectrum for a fiber-optical analog of the event horizon

Science.gov (United States)

Bermudez, David; Leonhardt, Ulf

2016-05-01

Hawking radiation has been regarded as a more general phenomenon than in gravitational physics, in particular in laboratory analogs of the event horizon. Here we consider the fiber-optical analog of the event horizon, where intense light pulses in fibers establish horizons for probe light. Then, we calculate the Hawking spectrum in an experimentally realizable system. We found that the Hawking radiation is peaked around group-velocity horizons in which the speed of the pulse matches the group velocity of the probe light. The radiation nearly vanishes at the phase horizon where the speed of the pulse matches the phase velocity of light.

On Long Memory Origins and Forecast Horizons

DEFF Research Database (Denmark)

Vera-Valdés, J. Eduardo

Most long memory forecasting studies assume that the memory is generated by the fractional difference operator. We argue that the most cited theoretical arguments for the presence of long memory do not imply the fractional difference operator, and assess the performance of the autoregressive...... fractionally integrated moving average (ARFIMA) model when forecasting series with long memory generated by nonfractional processes. We find that high-order autoregressive (AR) models produce similar or superior forecast performance than ARFIMA models at short horizons. Nonetheless, as the forecast horizon...... increases, the ARFIMA models tend to dominate in forecast performance. Hence, ARFIMA models are well suited for forecasts of long memory processes regardless of the long memory generating mechanism, particularly for medium and long forecast horizons. Additionally, we analyse the forecasting performance...

Organocatalytic Asymmetric Michael Addition of 4-Hydroxycoumarin to β,γ-Unsaturated α-Keto Esters

Energy Technology Data Exchange (ETDEWEB)

Suh, Chang Won; Han, Tae Hyun; Kim, Dae Young [Soonchunhyang Univ., Asan (Korea, Republic of)

2013-06-15

In conclusion, we have developed organocatalytic enantioselective conjugate addition reaction of 4-hydroxycoumarin (1) to β,γ-unsaturated α-keto esters 2 to afford biologically valuable warfarin derivatives 3. The process is efficiently catalyzed by a binaphthyl-modified thiourea organocatalyst. The coumarin core is present as a characteristic structural motif in a large number of natural products and biologically active molecules.1 Particularly, many of these naturally occurring 4-hydroxycoumarin and their synthetic analogues are important precursors for the synthesis of natural products and pharmaceuticals. Enantioselective organocatalytic conjugate addition of 4-hydroxycoumarin to α,β-unsaturated ketones is a straightforward method to access warfarin which is an effective anticoagulants. Although a number of reactions of α,β-unsaturated ketones as Michael acceptors have been reported, the corresponding β,γ-unsaturated α-keto esters have received relatively little attention as Michael acceptors. Recently, several groups have reported the asymmetric Michael addition of 4-hydroxycoumarin to β,γ-unsaturated α-keto esters catalyzed by Cu(II)-bisoxazoline, N,N'-dioxide-Ni(II) complexes, thiourea catalysts. Although several efficient methods have been achieved by these systems, an effective method for the synthesis of warfarin analogues is still a challenge.

Organocatalytic Asymmetric Michael Addition of 4-Hydroxycoumarin to β,γ-Unsaturated α-Keto Esters

International Nuclear Information System (INIS)

Suh, Chang Won; Han, Tae Hyun; Kim, Dae Young

2013-01-01

In conclusion, we have developed organocatalytic enantioselective conjugate addition reaction of 4-hydroxycoumarin (1) to β,γ-unsaturated α-keto esters 2 to afford biologically valuable warfarin derivatives 3. The process is efficiently catalyzed by a binaphthyl-modified thiourea organocatalyst. The coumarin core is present as a characteristic structural motif in a large number of natural products and biologically active molecules.1 Particularly, many of these naturally occurring 4-hydroxycoumarin and their synthetic analogues are important precursors for the synthesis of natural products and pharmaceuticals. Enantioselective organocatalytic conjugate addition of 4-hydroxycoumarin to α,β-unsaturated ketones is a straightforward method to access warfarin which is an effective anticoagulants. Although a number of reactions of α,β-unsaturated ketones as Michael acceptors have been reported, the corresponding β,γ-unsaturated α-keto esters have received relatively little attention as Michael acceptors. Recently, several groups have reported the asymmetric Michael addition of 4-hydroxycoumarin to β,γ-unsaturated α-keto esters catalyzed by Cu(II)-bisoxazoline, N,N'-dioxide-Ni(II) complexes, thiourea catalysts. Although several efficient methods have been achieved by these systems, an effective method for the synthesis of warfarin analogues is still a challenge

Deepwater Horizon - Baseline Dataset

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — In 2010, the Deepwater Horizon oil spill occurred in the Gulf of Mexico and the Natural Resources Damage Assessment (NRDA) was initiated to determine the extent of...

The power of virtual integration: an interview with Dell Computer's Michael Dell. Interview by Joan Magretta.

Science.gov (United States)

Dell, M

1998-01-01

Michael Dell started his computer company in 1984 with a simple business insight. He could bypass the dealer channel through which personal computers were then being sold and sell directly to customers, building products to order. Dell's direct model eliminated the dealer's markup and the risks associated with carrying large inventories of finished goods. In this interview, Michael Dell provides a detailed description of how his company is pushing that business model one step further, toward what he calls virtual integration. Dell is using technology and information to blur the traditional boundaries in the value chain between suppliers, manufacturers, and customers. The individual pieces of Dell's strategy--customer focus, supplier partnerships, mass customization, just-in-time manufacturing--may be all be familiar. But Michael Dell's business insight into how to combine them is highly innovative. Direct relationships with customers create valuable information, which in turn allows the company to coordinate its entire value chain back through manufacturing to product design. Dell describes how his company has come to achieve this tight coordination without the "drag effect" of ownership. Dell reaps the advantages of being vertically integrated without incurring the costs, all the while achieving the focus, agility, and speed of a virtual organization. As envisioned by Michael Dell, virtual integration may well become a new organizational model for the information age.

Review: Michael Crandall & Karen E. Fisher (Eds) Digital Inclusion: Measuring the Impact of Information and Community Technology

DEFF Research Database (Denmark)

Pors, Niels Ole

2010-01-01

Review: Michael Crandall & Karen E. Fisher (Eds) Digital Inclusion: Measuring the Impact of Information and Community Technology. Medford. Information Today. ASIS&T Monographs, 2009. 185 pages. $ 59.50. ISBN 978-1-57387-373-4......Review: Michael Crandall & Karen E. Fisher (Eds) Digital Inclusion: Measuring the Impact of Information and Community Technology. Medford. Information Today. ASIS&T Monographs, 2009. 185 pages. $ 59.50. ISBN 978-1-57387-373-4...

Michael K. Scullin: Psi Chi/APA Edwin B. Newman Graduate Research Award.

Science.gov (United States)

2011-11-01

Presents Michael K. Scullin as the 2011 winner of the American Psychological Association Psi Chi/APA Edwin B. Newman Graduate Research Award. "For an outstanding research paper that examines the relationship between prospective memory in executing a goal and various lapses of time from 20 minutes up to a 12- hour wake delay and a 12-hour sleep delay. The results suggest that consolidation processes active during sleep increase the probability of goal execution. The paper, titled 'Remembering to Execute a Goal: Sleep On It!' was published in Psychological Science in 2010 and was the basis for Michael K. Scullin's selection as the recipient of the 2011 Psi Chi/APA Edwin B. Newman Graduate Research Award. Mark A. McDaniel, PhD, served as faculty research advisor." (PsycINFO Database Record (c) 2011 APA, all rights reserved). 2011 APA, all rights reserved

Assessment of lipid profile of a group of undergraduates in Michael ...

African Journals Online (AJOL)

Objective: The aim of this study was to measure the lipid fractions in serum blood samples of apparently healthy undergraduates of Michael Okpara University of Agriculture, Umudike. Methods: A total of one hundred consenting males and females aged between 19-30 years were purposively selected from the ...

A celebration of mechanics: from nano to macro. The J. Michael T. Thompson Festschrift issue.

Science.gov (United States)

Elishakoff, Isaac

2013-06-28

This Theme Issue is dedicated to the topic 'Mechanics: from nano to macro' and marks the 75th birthday of Dr J. Michael T. Thompson, Fellow of the Royal Society, whose current affiliations are as follows: (i) Honorary Fellow, Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge; (ii) Emeritus Professor of Nonlinear Dynamics, Department of Civil, Environmental and Geomatic Engineering, University College London; and (iii) Professor of Theoretical and Applied Dynamics (Distinguished Sixth Century Chair, part-time), University of Aberdeen. He also serves as Chairman of the Board of Directors at ES-Consult (consulting engineers) in Copenhagen, Denmark. The pertinent question that arises from the very start is: should we first salute Michael and then describe the Theme Issue, or vice versa? Indeed, according to Blaise Pascal (1623-1662), the last thing one discovers in composing a work is what to put first. I would like to take the liberty of deviating from the tradition of the Philosophical Transactions and start with the tribute to Michael; after all he is the prime cause of this Theme Issue.

The two event horizons - an apparent contribution of vacuum to gravitation

International Nuclear Information System (INIS)

Dinculescu, A.

1994-01-01

Our possibilities of investigation are limited by two horizons: a local one - the black hole horizon R 0 , and the global one - the cosmic horizon R u . Till now, only the first horizon has been taken into consideration as a measure of the curvature of space near a massive body. It is argued that in order to satisfy Mach's principle when characterizing matter in a point relative to a center of mass, one has to take into consideration both event horizons. Accordingly, a local cosmological term Λ * =(R 0 R u ) -1 is defined as a combination of the above horizons in a given point. The corresponding non-dimensional coefficient ξ=Λ * R 2 is an indicator of the position of a mass point between the two event horizons. When taking into account as a contribution of vacuum energy to the gravitational field it restores the low of conservation of energy in an expanding universe, and explains the dynamics of galaxies and clusters of galaxies without resorting to the 'dark matter' hypothesis. (Author) 3 Tabs., 38 Refs

Proposed cuts to Horizon 2020 are short-sighted

CERN Multimedia

2015-01-01

When the latest incarnation of Europe’s framework programme for science funding, Horizon 2020, was announced, it was to great acclaim. Horizon 2020 builds on the already considerable success of its forerunners, which have made international research at the European level a reality and have contributed greatly to European competitiveness on the world stage.   We at CERN have benefited considerably, through projects that have enabled us to build on CERN’s core competencies to develop science at the grass-roots level across the continent. Horizon 2020 is more ambitious and more streamlined than its predecessors, and, funded at the level of €70 billion over seven years, it is potentially transformative. All of which makes the Commission’s plan to raid the Horizon 2020 budget to the tune of €2.7 billion rather incomprehensible. Keen to stimulate Europe’s economies, Commission President Jean-Claude Juncker has proposed a €21 billio...

VMware Horizon View 6 desktop virtualization cookbook

CERN Document Server

Ventresco, Jason

2014-01-01

If you want a more detailed explanation concerning the implementation of several different core features of VMware Horizon View, this is the book for you. Whether you are new to VMware Horizon View or an existing user, this book will provide you with the knowledge you need to successfully deploy several core features and get introduced to the latest features of version 6.0 as well.

Planning horizon affects prophylactic decision-making and epidemic dynamics.

Science.gov (United States)

Nardin, Luis G; Miller, Craig R; Ridenhour, Benjamin J; Krone, Stephen M; Joyce, Paul; Baumgaertner, Bert O

2016-01-01

The spread of infectious diseases can be impacted by human behavior, and behavioral decisions often depend implicitly on a planning horizon-the time in the future over which options are weighed. We investigate the effects of planning horizons on epidemic dynamics. We developed an epidemiological agent-based model (along with an ODE analog) to explore the decision-making of self-interested individuals on adopting prophylactic behavior. The decision-making process incorporates prophylaxis efficacy and disease prevalence with the individuals' payoffs and planning horizon. Our results show that for short and long planning horizons individuals do not consider engaging in prophylactic behavior. In contrast, individuals adopt prophylactic behavior when considering intermediate planning horizons. Such adoption, however, is not always monotonically associated with the prevalence of the disease, depending on the perceived protection efficacy and the disease parameters. Adoption of prophylactic behavior reduces the epidemic peak size while prolonging the epidemic and potentially generates secondary waves of infection. These effects can be made stronger by increasing the behavioral decision frequency or distorting an individual's perceived risk of infection.

Euroopa parimaks filmiks sai Michael Haneke "Valge lint" / Andres Laasik

Index Scriptorium Estoniae

Laasik, Andres, 1960-2016

2009-01-01

Euroopa Filmiakadeemia auhindadest: parima filmiauhinna sai Saksamaal Bochumis toimunud tseremoonial Michael Haneke "Valge lint", mille eest Haneke sai ka parima režissööri ja stsenaristi auhinna. Parimaks meesnäitlejaks pärjati Tahar Rahim ("Un Prophete"), parimaks naisnäitlejaks Kate Winslet ("The Reader"), publikupreemia sai Danny Boyle'i "Rentslimiljonär. Ka teistest võitjatest

Entropy bound of horizons for accelerating, rotating and charged Plebanski–Demianski black hole

International Nuclear Information System (INIS)

Debnath, Ujjal

2016-01-01

We first review the accelerating, rotating and charged Plebanski–Demianski (PD) black hole, which includes the Kerr–Newman rotating black hole and the Taub-NUT spacetime. The main feature of this black hole is that it has 4 horizons like event horizon, Cauchy horizon and two accelerating horizons. In the non-extremal case, the surface area, entropy, surface gravity, temperature, angular velocity, Komar energy and irreducible mass on the event horizon and Cauchy horizon are presented for PD black hole. The entropy product, temperature product, Komar energy product and irreducible mass product have been found for event horizon and Cauchy horizon. Also their sums are found for both horizons. All these relations are dependent on the mass of the PD black hole and other parameters. So all the products are not universal for PD black hole. The entropy and area bounds for two horizons have been investigated. Also we found the Christodoulou–Ruffini mass for extremal PD black hole. Finally, using first law of thermodynamics, we also found the Smarr relation for PD black hole.

Entropy bound of horizons for accelerating, rotating and charged Plebanski–Demianski black hole

Energy Technology Data Exchange (ETDEWEB)

Debnath, Ujjal, E-mail: ujjaldebnath@yahoo.com

2016-09-15

We first review the accelerating, rotating and charged Plebanski–Demianski (PD) black hole, which includes the Kerr–Newman rotating black hole and the Taub-NUT spacetime. The main feature of this black hole is that it has 4 horizons like event horizon, Cauchy horizon and two accelerating horizons. In the non-extremal case, the surface area, entropy, surface gravity, temperature, angular velocity, Komar energy and irreducible mass on the event horizon and Cauchy horizon are presented for PD black hole. The entropy product, temperature product, Komar energy product and irreducible mass product have been found for event horizon and Cauchy horizon. Also their sums are found for both horizons. All these relations are dependent on the mass of the PD black hole and other parameters. So all the products are not universal for PD black hole. The entropy and area bounds for two horizons have been investigated. Also we found the Christodoulou–Ruffini mass for extremal PD black hole. Finally, using first law of thermodynamics, we also found the Smarr relation for PD black hole.

Conference Offers Girls Opportunity to Expand Career Horizons

Science.gov (United States)

Offers Girls Opportunity to Expand Career Horizons For more information contact: e:mail: Public Affairs Golden, Colo., Feb. 11, 1997 -- Expanding Your Horizons, a conference for girls grades 6 - 9 and Employed Women, Girls Incorporated of Metro Denver, King Soopers, McDonalds, the TCI Adult Program and the

C. P. Snow's "The Two Cultures": Michael Polanyi's Response and Context

Science.gov (United States)

Jacobs, Struan

2011-01-01

C. P. Snow's "The Two Cultures" controversially contrasted science and literature, suggesting that neither scientists nor literary intellectuals have much in common with, and seldom bother speaking to, the other. Responding to Snow, Michael Polanyi argued that specialization has made modern culture, not twofold but manifold. In his major work,…

Event and Apparent Horizon Finders for 3 + 1 Numerical Relativity.

Science.gov (United States)

Thornburg, Jonathan

2007-01-01

Event and apparent horizons are key diagnostics for the presence and properties of black holes. In this article I review numerical algorithms and codes for finding event and apparent horizons in numerically-computed spacetimes, focusing on calculations done using the 3 + 1 ADM formalism. The event horizon of an asymptotically-flat spacetime is the boundary between those events from which a future-pointing null geodesic can reach future null infinity and those events from which no such geodesic exists. The event horizon is a (continuous) null surface in spacetime. The event horizon is defined nonlocally in time : it is a global property of the entire spacetime and must be found in a separate post-processing phase after all (or at least the nonstationary part) of spacetime has been numerically computed. There are three basic algorithms for finding event horizons, based on integrating null geodesics forwards in time, integrating null geodesics backwards in time, and integrating null surfaces backwards in time. The last of these is generally the most efficient and accurate. In contrast to an event horizon, an apparent horizon is defined locally in time in a spacelike slice and depends only on data in that slice, so it can be (and usually is) found during the numerical computation of a spacetime. A marginally outer trapped surface (MOTS) in a slice is a smooth closed 2-surface whose future-pointing outgoing null geodesics have zero expansion Θ. An apparent horizon is then defined as a MOTS not contained in any other MOTS. The MOTS condition is a nonlinear elliptic partial differential equation (PDE) for the surface shape, containing the ADM 3-metric, its spatial derivatives, and the extrinsic curvature as coefficients. Most "apparent horizon" finders actually find MOTSs. There are a large number of apparent horizon finding algorithms, with differing trade-offs between speed, robustness, accuracy, and ease of programming. In axisymmetry, shooting algorithms work well

Gravitational pressure, apparent horizon and thermodynamics of FLRW universe in the teleparallel gravity

Science.gov (United States)

da Rocha-Neto, J. F.; Morais, B. R.

2018-04-01

In the context of the teleparallel equivalent of general relativity the concept of gravitational pressure and gravitational energy-momentum arisen in a natural way. In the case of a Friedmann-Lemaitre-Robertson-Walker space FLRW we obtain the total energy contained inside the apparent horizon and the radial pressure over the apparent horizon area. We use these definitions to written a thermodynamics relation TAdSA = dEA+PAdVA at the apparent horizon, where EA is the total energy inside the apparent horizon, VA is the areal volume of the apparent horizon, PA is the radial pressure over the apparent horizon area, SA is the entropy which can be assumed as one quarter of the apparent horizon area only for a non stationary apparent horizon. We identify TA as the temperature at the surface of the apparent horizon. We shown that for all expanding accelerated FLRW model of universe the radial pressure is positive.

Geometric properties of static Einstein-Maxwell dilaton horizons with a Liouville potential

International Nuclear Information System (INIS)

Abdolrahimi, Shohreh; Shoom, Andrey A.

2011-01-01

We study nondegenerate and degenerate (extremal) Killing horizons of arbitrary geometry and topology within the Einstein-Maxwell-dilaton model with a Liouville potential (the EMdL model) in d-dimensional (d≥4) static space-times. Using Israel's description of a static space-time, we construct the EMdL equations and the space-time curvature invariants: the Ricci scalar, the square of the Ricci tensor, and the Kretschmann scalar. Assuming that space-time metric functions and the model fields are real analytic functions in the vicinity of a space-time horizon, we study the behavior of the space-time metric and the fields near the horizon and derive relations between the space-time curvature invariants calculated on the horizon and geometric invariants of the horizon surface. The derived relations generalize similar relations known for horizons of static four- and five-dimensional vacuum and four-dimensional electrovacuum space-times. Our analysis shows that all the extremal horizon surfaces are Einstein spaces. We present the necessary conditions for the existence of static extremal horizons within the EMdL model.

The Event Horizon of The Schwarzschild Black Hole in Noncommutative Spaces

OpenAIRE

Nasseri, Forough

2005-01-01

The event horizon of Schwarzschild black hole is obtained in noncommutative spaces up to the second order of perturbative calculations. Because this type of black hole is non-rotating, to the first order there is no any effect on the event horizon due to the noncommutativity of space. A lower limit for the noncommutativity parameter is also obtained. As a result, the event horizon in noncommutative spaces is less than the event horizon in commutative spaces.

On crossing the Cauchy horizon of a Reissner-Nordstroem black-hole

International Nuclear Information System (INIS)

Chandrasekhar, S.; Hartle, J.B.

1982-01-01

The behaviour, on the Cauchy horizon, of a flux of gravitational and/or electromagnetic radiation crossing the event horizon of a Reissner-Nordstroem black-hole is investigated as a problem in the theory of one-dimensional potential-scattering. It is shown that the flux of radiation received by an observer crossing the Cauchy horizon, along a radial time-like geodesic, diverges for all physically perturbations crossing the event horizon, even including those with compact support. (author)

Hydrogeochemical and stream sediment reconnaissance basic data for St. Michael Quadrangle, Alaska

International Nuclear Information System (INIS)

1981-01-01

Field and laboratory data are presented for 159 water samples from the St. Michael Quadrangle, Alaska. The samples were collected by Los Alamos National Laboratory; laboratory analysis and data reporting were performed by the Uranium Resource Evaluation Project at Oak Ridge, Tennessee

Euclidean scalar Green's functions near the black hole and black brane horizons

International Nuclear Information System (INIS)

Haba, Z

2009-01-01

We discuss approximations of the Riemannian geometry near the horizon. If a (D + 1)-dimensional manifold N has a bifurcate Killing horizon then we approximate N by a product of the two-dimensional Rindler space R 2 and a (D - 1)-dimensional Riemannian manifold M. We obtain approximate formulae for scalar Green's functions. We study the behavior of the Green's functions near the horizon and their dimensional reduction. We show that if M is compact then the Green's function near the horizon can be approximated by the Green's function of the two-dimensional quantum field theory. The correction term is exponentially small away from the horizon. We extend the results to black brane solutions of supergravity in 10 and 11 dimensions. The near-horizon geometry can be approximated by N=AdS p xS q . We discuss the Euclidean Green's functions on N and their behavior near the horizon.

Astronaut C. Michael Foale is briefed on use of Sky Genie

Science.gov (United States)

1994-01-01

Astronaut C. Michael Foale, STS-63 mission specialist, is briefed on the use of Sky Genie device by Karin L. Porter. The device would aid in emergency egress operations aboard a troubled Space Shuttle. Porter, an employee of Rockwell International, helps train astronauts in egress procedures at JSC's Shuttle mockup and integration laboratory.

Little Mosie from the Margaree: A Biography of Moses Michael Coady.

Science.gov (United States)

Welton, Michael R.

This book examines the life of the Reverend Moses Michael Coady (1890-1959), a Roman Catholic priest who led the Antigonish Movement. During the Antigonish Movement, residents of the small maritime town of Antigonish, Nova Scotia, worked to achieve a nonviolent alternative to communism and fascism and to effect the social and economic…

Measuring Item Fill-Rate Performance in a Finite Horizon

OpenAIRE

Douglas J. Thomas

2005-01-01

The standard treatment of fill rate relies on stationary and serially independent demand over an infinite horizon. Even if demand is stationary, managers are held accountable for performance over a finite horizon. In a finite horizon, the fill rate is a random variable. Studying the distribution is relevant because a vendor may be subject to financial penalty if she fails to achieve her target fill rate over a specified finite period. It is known that for a zero lead time, base-stock model, t...

Structure of diagnostics horizons and humus classification

Directory of Open Access Journals (Sweden)

Zanella A

2008-03-01

Full Text Available The classification of the main humus forms is generally based on the morpho-genetic characters of the A and OH diagnostic horizons. This is the case in the new European key of classification presented in Freiburg on September 2004 (Eurosoil Congress. Among the morpho-genetic characters, the soil structure covers a very important role. In this work, the structure of the diagnostic A and OH horizons has been analysed in terms of aggregation force, diameter and composition of the soil lumps (peds. In order to study the aggregation force, two disaggregating tools have been conceived and used. The diameter of the lumps has been measured by sieving the soil samples with standardised webs. Observing the samples thanks to a binocular magnifying 10X and 50X, the organic or/and mineral composition of the soil aggregates has been determined, data being investigated with ANOVA and Factorial Analysis. The article examines the argument from two points of view: crashing tools for estimating the soil structure (part 1 and the dimensions of the peds given in European key of humus forms classification (part 2. The categories of soil peds diameter and composition seem to be linked to the main humus forms. For instance, aggregates having a diamater larger than 1 mm and well amalgamate organo-mineral composition are more present in the A horizons of the Mull forms than in which of the other forms; contrary to the OH horizon of the Moder or Mor, the OH horizon of the Amphi forms shows an important percent of small organic lumps. Some propositions have been given in order to improve the European key of humus forms classification.

Horizon Scanning for Pharmaceuticals

DEFF Research Database (Denmark)

Lepage-Nefkens, Isabelle; Douw, Karla; Mantjes, GertJan

for a joint horizon scanning system (HSS).  We propose to create a central “horizon scanning unit” to perform the joint HS activities (a newly established unit, an existing HS unit, or a third party commissioned and financed by the collaborating countries). The unit will be responsible for the identification...... and filtration of new and emerging pharmaceutical products. It will maintain and update the HS database, organise company pipeline meetings, and disseminate the HSS’s outputs.  The HS unit works closely together with the designated national HS experts in each collaborating country. The national HS experts...... will collect country-specific information, liaise between the central HS unit and country-specific clinical and other experts, coordinate the national prioritization process (to select products for early assessment), and communicate the output of the HSS to national decision makers.  The outputs of the joint...

Near-horizon symmetries of extremal black holes

International Nuclear Information System (INIS)

Kunduri, Hari K; Lucietti, James; Reall, Harvey S

2007-01-01

Recent work has demonstrated an attractor mechanism for extremal rotating black holes subject to the assumption of a near-horizon SO(2, 1) symmetry. We prove the existence of this symmetry for any extremal black hole with the same number of rotational symmetries as known four- and five-dimensional solutions (including black rings). The result is valid for a general two-derivative theory of gravity coupled to Abelian vectors and uncharged scalars, allowing for a non-trivial scalar potential. We prove that it remains valid in the presence of higher-derivative corrections. We show that SO(2, 1)-symmetric near-horizon solutions can be analytically continued to give SU(2)-symmetric black hole solutions. For example, the near-horizon limit of an extremal 5D Myers-Perry black hole is related by analytic continuation to a non-extremal cohomogeneity-1 Myers-Perry solution

Infinite-horizon optimal control problems in economics

International Nuclear Information System (INIS)

Aseev, Sergei M; Besov, Konstantin O; Kryazhimskii, Arkadii V

2012-01-01

This paper extends optimal control theory to a class of infinite-horizon problems that arise in studying models of optimal dynamic allocation of economic resources. In a typical problem of this sort the initial state is fixed, no constraints are imposed on the behaviour of the admissible trajectories at large times, and the objective functional is given by a discounted improper integral. We develop the method of finite-horizon approximations in a broad context and use it to derive complete versions of the Pontryagin maximum principle for such problems. We provide sufficient conditions for the normality of infinite-horizon optimal control problems and for the validity of the 'standard' limit transversality conditions with time going to infinity. As a meaningful example, we consider a new two-sector model of optimal economic growth subject to a random jump in prices. Bibliography: 53 titles.

Does the black hole shadow probe the event horizon geometry?

Science.gov (United States)

Cunha, Pedro V. P.; Herdeiro, Carlos A. R.; Rodriguez, Maria J.

2018-04-01

There is an exciting prospect of obtaining the shadow of astrophysical black holes (BHs) in the near future with the Event Horizon Telescope. As a matter of principle, this justifies asking how much one can learn about the BH horizon itself from such a measurement. Since the shadow is determined by a set of special photon orbits, rather than horizon properties, it is possible that different horizon geometries yield similar shadows. One may then ask how sensitive is the shadow to details of the horizon geometry? As a case study, we consider the double Schwarzschild BH and analyze the impact on the lensing and shadows of the conical singularity that holds the two BHs in equilibrium—herein taken to be a strut along the symmetry axis in between the two BHs. Whereas the conical singularity induces a discontinuity of the scattering angle of photons, clearly visible in the lensing patterns along the direction of the strut's location, it produces no observable effect on the shadows, whose edges remain everywhere smooth. The latter feature is illustrated by examples including both equal and unequal mass BHs. This smoothness contrasts with the intrinsic geometry of the (spatial sections of the) horizon of these BHs, which is not smooth, and provides a sharp example on how BH shadows are insensitive to some horizon geometry details. This observation, moreover, suggests that for the study of their shadows, this static double BH system may be an informative proxy for a dynamical binary.

Fractal markets: Liquidity and investors on different time horizons

Science.gov (United States)

Li, Da-Ye; Nishimura, Yusaku; Men, Ming

2014-08-01

In this paper, we propose a new agent-based model to study the source of liquidity and the “emergent” phenomenon in financial market with fractal structure. The model rests on fractal market hypothesis and agents with different time horizons of investments. What is interesting is that though the agent-based model reveals that the interaction between these heterogeneous agents affects the stability and liquidity of the financial market the real world market lacks detailed data to bring it to light since it is difficult to identify and distinguish the investors with different time horizons in the empirical approach. results show that in a relatively short period of time fractal market provides liquidity from investors with different horizons and the market gains stability when the market structure changes from uniformity to diversification. In the real world the fractal structure with the finite of horizons can only stabilize the market within limits. With the finite maximum horizons, the greater diversity of the investors and the fractal structure will not necessarily bring more stability to the market which might come with greater fluctuation in large time scale.

A redefinition of Hawking temperature on the event horizon: Thermodynamical equilibrium

International Nuclear Information System (INIS)

Saha, Subhajit; Chakraborty, Subenoy

2012-01-01

In this Letter we have used the recently introduced redefined Hawking temperature on the event horizon and investigated whether the generalized second law of thermodynamics (GSLT) and thermodynamic equilibrium holds for both the event and the apparent horizons. Here we have considered FRW universe and examined the GSLT and thermodynamic equilibrium with three examples. Finally, we have concluded that from the thermodynamic viewpoint, the universe bounded by the event horizon is more realistic than that by the apparent horizon at least for some examples.

On the topology of stationary black hole event horizons in higher dimensions

International Nuclear Information System (INIS)

Helfgott, Craig; Oz, Yaron; Yanay, Yariv

2006-01-01

In four dimensions the topology of the event horizon of an asymptotically flat stationary black hole is uniquely determined to be the two-sphere S 2 . We consider the topology of event horizons in higher dimensions. First, we reconsider Hawking's theorem and show that the integrated Ricci scalar curvature with respect to the induced metric on the event horizon is positive also in higher dimensions. Using this and Thurston's geometric types classification of three-manifolds, we find that the only possible geometric types of event horizons in five dimensions are S 3 and S 2 x S 1 . In six dimensions we use the requirement that the horizon is cobordant to a four-sphere (topological censorship), Friedman's classification of topological four-manifolds and Donaldson's results on smooth four-manifolds, and show that simply connected event horizons are homeomorphic to S 4 or S 2 x S 2 . We show that the non-simply connected event horizons S 3 x S 1 and S 2 x Σ g and event horizons with finite non-abelian first homotopy group whose universal cover is S 4 , are possible. Finally, we discuss the classification in dimensions higher than six

Moral Education and Education in Altruism: Two Replies to Michael Hand

Science.gov (United States)

White, John

2016-01-01

This article is a critical discussion of two recent papers by Michael Hand on moral education. The first is his "Towards a Theory of Moral Education", published in the "Journal of Philosophy of Education" in 2014 (Volume 48, Issue 4). The second is a chapter called "Beyond Moral Education?" in an edited book of new…

A Critical Analysis of Michael Tippett's "A Child of Our Time"

Science.gov (United States)

Vallee, Jean-Sebastien

2009-01-01

After more than ten years of thoughtful planning, Michael Tippett (1905-1998) summed up his musical, political, spiritual and philosophical beliefs in his first oratorio, "A Child of Our Time" (1941). Representing the emergence of a new level of confidence and musical maturity for Tippett, the oratorio has become the composer's most widely known…

Gulliver's Travels: Michael Moore the Explorer in "Who to Invade Next"

Science.gov (United States)

Beck, Bernard

2016-01-01

America is identified as a nation of immigrants. These immigrants are thought to be the source of its subcultures. It is also a nation of individual explorers and inventors. Their activities are also a source of diverse subcultures. Many notable movies have made heroes of such innovators in different fields of endeavor. Michael Moore's movie…

An Interview with Michael Horn: Blending Education for High-Octane Motivation

Science.gov (United States)

Patterson, Gregory A.

2012-01-01

Blended learning holds the potential of improving the way we educate students and of making them more motivated. Blended education--the melding of information technology based distance learning with school attendance--is perhaps the best way to educate students for 21st century skills, says Michael Horn in a "Kappan" interview. Horn points out…

Gravitational black hole hair from event horizon supertranslations

Energy Technology Data Exchange (ETDEWEB)

Averin, Artem [Arnold-Sommerfeld-Center for Theoretical Physics,Ludwig-Maximilians-Universität, 80333 München (Germany); Max-Planck-Institut für Physik, Werner-Heisenberg-Institut,80805 München (Germany); Dvali, Gia [Arnold-Sommerfeld-Center for Theoretical Physics,Ludwig-Maximilians-Universität, 80333 München (Germany); Max-Planck-Institut für Physik, Werner-Heisenberg-Institut,80805 München (Germany); Center for Cosmology and Particle Physics, Department of Physics, New York University,4 Washington Place, New York, NY 10003 (United States); Gomez, Cesar [Instituto de Física Teórica UAM-CSIC, C-XVI, Universidad Autónoma de Madrid,Cantoblanco, 28049 Madrid (Spain); Lüst, Dieter [Arnold-Sommerfeld-Center for Theoretical Physics,Ludwig-Maximilians-Universität, 80333 München (Germany); Max-Planck-Institut für Physik, Werner-Heisenberg-Institut,80805 München (Germany)

2016-06-16

We discuss BMS supertranslations both at null-infinity BMS{sup −} and on the horizon BMS{sup H} for the case of the Schwarzschild black hole. We show that both kinds of supertranslations lead to infinetly many gapless physical excitations. On this basis we construct a quotient algebra A≡BMS{sup H}/BMS{sup −} using suited superpositions of both kinds of transformations which cannot be compensated by an ordinary BMS-supertranslation and therefore are intrinsically due to the presence of an event horizon. We show that transformations in A are physical and generate gapless excitations on the horizon that can account for the gravitational hair as well as for the black hole entropy. We identify the physics of these modes as associated with Bogolioubov-Goldstone modes due to quantum criticality. Classically the number of these gapless modes is infinite. However, we show that due to quantum criticality the actual amount of information-carriers becomes finite and consistent with Bekenstein entropy. Although we only consider the case of Schwarzschild geometry, the arguments are extendable to arbitrary space-times containing event horizons.

Gravitational black hole hair from event horizon supertranslations

International Nuclear Information System (INIS)

Averin, Artem; Dvali, Gia; Gomez, Cesar; Lüst, Dieter

2016-01-01

We discuss BMS supertranslations both at null-infinity BMS"− and on the horizon BMS"H for the case of the Schwarzschild black hole. We show that both kinds of supertranslations lead to infinetly many gapless physical excitations. On this basis we construct a quotient algebra A≡BMS"H/BMS"− using suited superpositions of both kinds of transformations which cannot be compensated by an ordinary BMS-supertranslation and therefore are intrinsically due to the presence of an event horizon. We show that transformations in A are physical and generate gapless excitations on the horizon that can account for the gravitational hair as well as for the black hole entropy. We identify the physics of these modes as associated with Bogolioubov-Goldstone modes due to quantum criticality. Classically the number of these gapless modes is infinite. However, we show that due to quantum criticality the actual amount of information-carriers becomes finite and consistent with Bekenstein entropy. Although we only consider the case of Schwarzschild geometry, the arguments are extendable to arbitrary space-times containing event horizons.

Quantum correlations through event horizons: Fermionic versus bosonic entanglement

International Nuclear Information System (INIS)

Martin-Martinez, Eduardo; Leon, Juan

2010-01-01

We disclose the behavior of quantum and classical correlations among all the different spatial-temporal regions of a space-time with an event horizon, comparing fermionic with bosonic fields. We show the emergence of conservation laws for entanglement and classical correlations, pointing out the crucial role that statistics plays in the information exchange (and more specifically, the entanglement tradeoff) across horizons. The results obtained here could shed new light on the problem of information behavior in noninertial frames and in the presence of horizons, giving better insight into the black-hole information paradox.

Cleaning up with genomics: applying molecular biology to bioremediation.

Science.gov (United States)

Lovley, Derek R

2003-10-01

Bioremediation has the potential to restore contaminated environments inexpensively yet effectively, but a lack of information about the factors controlling the growth and metabolism of microorganisms in polluted environments often limits its implementation. However, rapid advances in the understanding of bioremediation are on the horizon. Researchers now have the ability to culture microorganisms that are important in bioremediation and can evaluate their physiology using a combination of genome-enabled experimental and modelling techniques. In addition, new environmental genomic techniques offer the possibility for similar studies on as-yet-uncultured organisms. Combining models that can predict the activity of microorganisms that are involved in bioremediation with existing geochemical and hydrological models should transform bioremediation from a largely empirical practice into a science.

Tandem Michael addition/radical cyclizations for the construction of highly functionalized cyclopentanes

Czech Academy of Sciences Publication Activity Database

Holan, Martin; Pohl, Radek; Císarová, I.; Jahn, Ullrich

2012-01-01

Roč. 106, - (2012), s1298-s1298 ISSN 0009-2770. [EuCheMS Chemistry Congress /4./. 26.08.2012-30.08.2012, Prague] Institutional research plan: CEZ:AV0Z40550506 Keywords : cyclization * diastereoselectivity * Michael addiction * radical reactions * domino reactions Subject RIV: CC - Organic Chemistry

Highly Functionalized Cyclopentane Derivatives by Tandem Michael Addition/Radical Cyclization/Oxygenation Reactions

Czech Academy of Sciences Publication Activity Database

Holan, Martin; Pohl, Radek; Císařová, I.; Klepetářová, Blanka; Jones, P. G.; Jahn, Ullrich

2015-01-01

Roč. 21, č. 27 (2015), s. 9877-9888 ISSN 0947-6539 R&D Projects: GA ČR GA13-40188S Institutional support: RVO:61388963 Keywords : cyclization * domino reactions * electron transfer * Michael addition * radical reactions Subject RIV: CC - Organic Chemistry Impact factor: 5.771, year: 2015

An efficient oxa-Michael addition to diethyl vinylphosphonate under mild reaction conditions

Czech Academy of Sciences Publication Activity Database

Baszczyňski, Ondřej; Jansa, Petr; Dračínský, Martin; Kaiser, Martin Maxmilian; Špaček, Petr; Janeba, Zlatko

2012-01-01

Roč. 2, č. 4 (2012), s. 1282-1284 ISSN 2046-2069 R&D Projects: GA MV VG20102015046 Institutional research plan: CEZ:AV0Z40550506 Keywords : oxa-Michael addition * secondary alcohols * diethyl vinylphosphonate Subject RIV: CC - Organic Chemistry Impact factor: 2.562, year: 2012

Q & A with Ed Tech Leaders: Interview with Michael W. Allen

Science.gov (United States)

Shaughnessy, Michael F.

2014-01-01

Michael W. Allen, the Chairman and CEO of Allen Interactions, is an architect of interactive multimedia learning and is recognized for his many insights, inventions, and presentations. With over 50 years of experience in e-learning, both in academic and corporate settings, he is known for his role in creating Authorware and overseeing the work of…

Is thermodynamics of the universe bounded by event horizon a Bekenstein system?

International Nuclear Information System (INIS)

Chakraborty, Subenoy

2012-01-01

In this brief communication, we have studied the validity of the first law of thermodynamics for the universe bounded by event horizon with two examples. The key point is the appropriate choice of the temperature on the event horizon. Finally, we have concluded that universe bounded by the event horizon may be a Bekenstein system and Einstein's equations and the first law of thermodynamics on the event horizons are equivalent.

Is thermodynamics of the universe bounded by event horizon a Bekenstein system?

OpenAIRE

Chakraborty, Subenoy

2012-01-01

In this brief communication, we have studied the validity of the first law of thermodynamics for the universe bounded by event horizon with two examples. The key point is the appropriate choice of the temperature on the event horizon. Finally, we have concluded that universe bounded by the event horizon may be a Bekenstein system and the Einstein's equations and the first law of thermodynamics on the event horizons are equivalent.

Michael Polanyi and his generation origins of the social construction of science

CERN Document Server

Nye, Mary Jo

2011-01-01

In Michael Polanyi and His Generation, Mary Jo Nye investigates the role that Michael Polanyi and several of his contemporaries played in the emergence of the social turn in the philosophy of science. This turn involved seeing science as a socially based enterprise that does not rely on empiricism and reason alone but on social communities, behavioral norms, and personal commitments. Nye argues that the roots of the social turn are to be found in the scientific culture and political events of Europe in the 1930s, when scientific intellectuals struggled to defend the universal status of scientific knowledge and to justify public support for science in an era of economic catastrophe, Stalinism and Fascism, and increased demands for applications of science to industry and social welfare. At the center of this struggle was Polanyi, who Nye contends was one of the first advocates of this new conception of science. Nye reconstructs Polanyi’s scientific and political milieus in Budapest, Berlin, and Manchester f...

A global string with an event horizon

International Nuclear Information System (INIS)

Harari, D.; Polychronakos, A.P.

1990-01-01

An idealized infinite straight global string in flat space-time has a logarithmically divergent energy per unit length. With gravity included, the standard field theoretical model for a straight global string has been shown to give rise to a repulsive gravitational field, and to develop a curvature singularity at a finite proper distance off the string core. Here we point out that alternative (although probably unrealistic) equations of state for the core of the global string produce a non-singular cylindrically symmetric metric with an event horizon at a finite proper distance off the core, such that timelike observers beyond the horizon are bound to move away from the string. The same geometric structure applies to the standard field theoretical model for a vortex in (2+1)-dimensional gravity. Thermal effects in a quantum field theory around the string due to the presence of the horizon are also calculated. (orig.)

Infinite-horizon optimal control problems in economics

Energy Technology Data Exchange (ETDEWEB)

Aseev, Sergei M; Besov, Konstantin O; Kryazhimskii, Arkadii V

2012-04-30

This paper extends optimal control theory to a class of infinite-horizon problems that arise in studying models of optimal dynamic allocation of economic resources. In a typical problem of this sort the initial state is fixed, no constraints are imposed on the behaviour of the admissible trajectories at large times, and the objective functional is given by a discounted improper integral. We develop the method of finite-horizon approximations in a broad context and use it to derive complete versions of the Pontryagin maximum principle for such problems. We provide sufficient conditions for the normality of infinite-horizon optimal control problems and for the validity of the 'standard' limit transversality conditions with time going to infinity. As a meaningful example, we consider a new two-sector model of optimal economic growth subject to a random jump in prices. Bibliography: 53 titles.

Radiation from quantum weakly dynamical horizons in loop quantum gravity.

Science.gov (United States)

Pranzetti, Daniele

2012-07-06

We provide a statistical mechanical analysis of quantum horizons near equilibrium in the grand canonical ensemble. By matching the description of the nonequilibrium phase in terms of weakly dynamical horizons with a local statistical framework, we implement loop quantum gravity dynamics near the boundary. The resulting radiation process provides a quantum gravity description of the horizon evaporation. For large black holes, the spectrum we derive presents a discrete structure which could be potentially observable.

Thermodynamics of the Apparent Horizon in FRW Universe with Massive Gravity

International Nuclear Information System (INIS)

Li Hui; Zhang Yi

2013-01-01

Applying Clausius relation with energy-supply defined by the unified first law of thermodynamics formalism to the apparent horizon of a massive gravity model in cosmology proposed lately, the corrected entropic formula of the apparent horizon is obtained with the help of the modified Friedmann equations. This entropy-area relation, together with the identified Misner-Sharp internal energy, verifies the first law of thermodynamics for the apparent horizon with a volume change term for consistency. On the other hand, by means of the corrected entropy-area formula and the Clausius relation δQ = T d S, where the heat Bow δQ is the energy-supply of pure matter projecting on the vector ξ tangent to the apparent horizon and should be looked on as the amount of energy crossing the apparent horizon during the time interval dt and the temperature of the apparent horizon for energy crossing during the same interval is 1/(2πr A ), the modified Friedmann equations governing the dynamical evolution of the universe are reproduced with the known energy density and pressure of massive graviton. The integration constant is found to correspond to a cosmological term which could be absorbed into the energy density of matter. Having established the correspondence of massive cosmology with the unified first law of thermodynamics on the apparent horizon, the validity of the generalized second law of thermodynamics is also discussed by assuming the thermal equilibrium between the apparent horizon and the matter field bounded by the apparent horizon. It is found that, in the limit H c → 0, which recovers the Minkowski reference metric solution in the fiat case, the generalized second law of thermodynamics holds if α 3 + 4α 4 3 = α 4 = 0, the generalized second law of thermodynamics could be violated. (general)

Quantum statistical entropy corresponding to cosmic horizon in five-dimensional spacetime

Institute of Scientific and Technical Information of China (English)

2008-01-01

The generalized uncertainty relation is introduced to calculate the quantum statis-tical entropy corresponding to cosmic horizon. By using the new equation of state density motivated by the generalized uncertainty relation, we discuss entropies of Bose field and Fermi field on the background of five-dimensional spacetime. In our calculation, we need not introduce cutoff. There is no divergent logarithmic term in the original brick-wall method. And it is obtained that the quantum statistical en-tropy corresponding to cosmic horizon is proportional to the area of the horizon. Further it is shown that the entropy corresponding to cosmic horizon is the entropy of quantum state on the surface of horizon. The black hole’s entropy is the intrinsic property of the black hole. The entropy is a quantum effect. In our calculation, by using the quantum statistical method, we obtain the partition function of Bose field and Fermi field on the background of five-dimensional spacetime. We provide a way to study the quantum statistical entropy corresponding to cosmic horizon in the higher-dimensional spacetime.

Book Review: America’s Blind Spot: Chávez, Oil and US Security by Andrés Cala and Michael Economides

DEFF Research Database (Denmark)

Boscan, Luis

2014-01-01

Review of: America’s Blind Spot: Chávez, Oil and US Security. Andrés Cala and Michael Economides. Continuum Books. 2012.......Review of: America’s Blind Spot: Chávez, Oil and US Security. Andrés Cala and Michael Economides. Continuum Books. 2012....

Towards what Horizon is EU headed by 2020?

Directory of Open Access Journals (Sweden)

Maria Mirona Murea

2013-12-01

Full Text Available Horizon 2020, is a legislative package that succeeds the current FP7, with a proposed budget of EURO 70.9 billion and it has been seen as a response measure to the economic and financial crisis, by creatig the possibilities to invest in future jobs and growth, while addressing EU citizens about their safety, livelihoods and environment. Reliying on a three pillar structure, the funding model focuses on providing the participants similar funding rates according to the undertaken activities, while taking into consideration stakeholders’ preferences for reimbursement. Horizon 2020 is open to any project that is based on competitive initiatives; however, each country’s experience and economic development will influence its’ participation to the “Horizon 2020” funding program.

Parametric Covariance Model for Horizon-Based Optical Navigation

Science.gov (United States)

Hikes, Jacob; Liounis, Andrew J.; Christian, John A.

2016-01-01

This Note presents an entirely parametric version of the covariance for horizon-based optical navigation measurements. The covariance can be written as a function of only the spacecraft position, two sensor design parameters, the illumination direction, the size of the observed planet, the size of the lit arc to be used, and the total number of observed horizon points. As a result, one may now more clearly understand the sensitivity of horizon-based optical navigation performance as a function of these key design parameters, which is insight that was obscured in previous (and nonparametric) versions of the covariance. Finally, the new parametric covariance is shown to agree with both the nonparametric analytic covariance and results from a Monte Carlo analysis.

Enantio- and Stereoselective Construction of Atisane Scaffold via Organocatalytic Intramolecular Michael Reaction and Diels-Alder Reaction.

Science.gov (United States)

Sekita, Hiroko; Adachi, Kyohei; Kobayashi, Ippei; Sato, Yusuke; Nakada, Masahisa

2017-05-05

An enantio- and stereoselective construction of the atisane scaffold via organocatalytic intramolecular Michael reaction and Diels-Alder reaction is described. The organocatalytic intramolecular Michael reaction has been found to stereoselectively generate a trans-stereodiad comprising an all-carbon quaternary and a tertiary stereogenic centers. Use of the chiral secondary amine bearing thiourea with benzoic acid as additive is the key to obtaining the desired product with excellent ee in synthetically acceptable yield. The prepared chiral building block has been successfully converted to the compound including the atisane scaffold via the highly stereoselective intramolecular Diels-Alder reaction.

A Greener, Efficient Approach to Michael Addition of Barbituric Acid to Nitroalkene in Aqueous Diethylamine Medium

Directory of Open Access Journals (Sweden)

Hany J. Al-Najjar

2014-01-01

Full Text Available An efficient method for the synthesis of a variety of pyrimidine derivatives 3a–t by reaction of barbituric acids 1a,b as Michael donor with nitroalkenes 2a–k as Michael acceptor using an aqueous medium and diethylamine is described. This 1,4-addition strategy offers several advantages, such as using an economic and environmentally benign reaction media, high yields, versatility, and shorter reaction times. The synthesized compounds were identified by 1H-NMR, 13C-NMR, CHN, IR, and MS. The structure of compound 3a was further confirmed by single crystal X-ray structure determination.

Theory and practice in action: the contributions of Michael Perkins to clinical linguistics.

Science.gov (United States)

Damico, Jack S; Lynch, Karen E

2013-01-01

This article reviews the scholarly contributions of Michael R. Perkins in the discipline of clinical linguistics and provides some indication of the reasons that he has been so successful. Three primary attributes were described through an analysis of his publications.

Nitrogen isotope ratios in surface and sub-surface soil horizons

International Nuclear Information System (INIS)

Rennie, D.A.; Paul, E.A.

1975-01-01

Nitrogen isotope analysis of surface soils and soil-derived nitrate for selected chernozemic and luvisolic soils showed mean delta 15 N values of 11.7 and 11.3, respectively. Isotope enrichment of the total N reached a maximum in the lower B horizon. Sub-soil parent material samples from the one deep profile included in the study indicated a delta 15 N value (NO 3 -N) of 1/3 that of the Ap horizon, at a depth of 180 cm. The delta 15 N of sub-surface soil horizons containing residual fertilizer N were low (-2.2) compared to the surface horizon (9.9). The data reported from this preliminary survey suggest that the natural variations in 15 N abundance between different soils and horizons of the same soil reflect the cumulative effects of soil genesis and soil management. More detailed knowledge and understanding of biological and other processes which control N isotope concentrations in these soils must be obtained before the data reported can be interpreted. (author)

High-dimensional covariance forecasting for short intra-day horizons

NARCIS (Netherlands)

Oomen, R.C.A.

2010-01-01

Asset return covariances at intra-day horizons are known to tend towards zero due to market microstructure effects. Thus, traders who simply scale their daily covariance forecast to match their trading horizon are likely to over-estimate the actual experienced asset dependence. In this paper, some

Genesis of petroduric and petrocalcic horizons in Latinamerica volcanic soils

Science.gov (United States)

Quantin, Paul

2010-05-01

Introduction. In Latinamerica, from Mexico to Chile, there are indurated volcanic soils horizons, named 'tepetate' in Mexico or cangahua in the Andes Mountains. Apart from original volcanic tuffs, these horizons were produced by pedogenesis: either through a former weathering of volcanic ash layers into fragic and later to petrocalcic horizons; or after a former soil formation through a second process of transformation from clayey volcanic soils to silicified petroduric horizons. This oral presentation will briefly deal with the formation of petroduric horizons in Mexico and petrocalcic horizon in Ecuador. Petroduric horizon genesis in Mexico. A soil climato-toposequence, near to Veracruz (Rossignol & Quantin, 1997), shows downwards an evolution from a ferralic Nitisol to a petroduric Durisol. A Durisol profile comports these successive horizons: at the top A and Eg, then columnar Btg-sim, laminar Bt-sim , prismatic Bsim, plinthite Cg, over andesite lava flow. Among its main features are especially recorded: clay mineralogy, microscopy and HRTEM. These data show: an increase in cristobalite at the expenses of 0.7 nm halloysite in Egsiltans, laminar Bt-sim, around or inside the columns or prisms of Btg-sim and Bsimhorizons. HRTEM (Elsass & al 2000) on ultra thin sections reveals an 'epigenesis' of clay sheets by amorphous silica, to form successively A-opal, Ct-opal and microcrystalline cristobalite. From these data and some groundwater chemical analyses, a scenario of duripan formation from a past clayey Nitisol is inferred: clay eluviation-illuviation process? alternate redoximorphy? clay degradation, Al leaching and Si accumulation, to form successively A-opal, Ct-opal and cristobalite. Petrocalcic horizon genesis in Ecuador. A soil climato-toposequence on pyroclastic flows, near to Bolivar in Ecuador (Quantin & Zebrowski, 1997), shows downwards the evolution from fragic-eutric-vitric Cambisols to petrocalcic-vitric Phaeozems, at the piedmont under semi

Turnpike phenomenon and infinite horizon optimal control

CERN Document Server

Zaslavski, Alexander J

2014-01-01

This book is devoted to the study of the turnpike phenomenon and describes the existence of solutions for a large variety of infinite horizon optimal control classes of problems.  Chapter 1 provides introductory material on turnpike properties. Chapter 2 studies the turnpike phenomenon for discrete-time optimal control problems. The turnpike properties of autonomous problems with extended-value intergrands are studied in Chapter 3. Chapter 4 focuses on large classes of infinite horizon optimal control problems without convexity (concavity) assumptions. In Chapter 5, the turnpike results for a class of dynamic discrete-time two-player zero-sum game are proven. This thorough exposition will be very useful  for mathematicians working in the fields of optimal control, the calculus of variations, applied functional analysis, and infinite horizon optimization. It may also be used as a primary text in a graduate course in optimal control or as supplementary text for a variety of courses in other disciplines. Resea...

Black hole and cosmos with multiple horizons and multiple singularities in vector-tensor theories

Science.gov (United States)

Gao, Changjun; Lu, Youjun; Yu, Shuang; Shen, You-Gen

2018-05-01

A stationary and spherically symmetric black hole (e.g., Reissner-Nordström black hole or Kerr-Newman black hole) has, at most, one singularity and two horizons. One horizon is the outer event horizon and the other is the inner Cauchy horizon. Can we construct static and spherically symmetric black hole solutions with N horizons and M singularities? The de Sitter cosmos has only one apparent horizon. Can we construct cosmos solutions with N horizons? In this article, we present the static and spherically symmetric black hole and cosmos solutions with N horizons and M singularities in the vector-tensor theories. Following these motivations, we also construct the black hole solutions with a firewall. The deviation of these black hole solutions from the usual ones can be potentially tested by future measurements of gravitational waves or the black hole continuum spectrum.

Organocatalytic asymmetric michael addition of aldehydes to beta-nitroacroleine dimethyl acetal.

Science.gov (United States)

Reyes, Efraim; Vicario, Jose L; Badía, Dolores; Carrillo, Luisa

2006-12-21

[Structure: see text] The organocatalytic asymmetric Michael addition of aldehydes to beta-nitroacroleine dimethyl acetal has been studied in detail. The reaction took place with excellent yields and high stereoselectivities when a chiral beta-amino alcohol such as L-prolinol was employed as the catalyst, leaving a formation of highly functionalized enantioenriched compounds containing two differentiated formyl groups together with a nitro moiety.

Learned Helplessness Encountered by Michael Oher in the Blind Side Movie

OpenAIRE

PAMUNGKAS, DIMAS PROBO

2014-01-01

Pamungkas, Dimas Probo. 2014. Learned Helplessness Encountered by Michael Oher in The Blind Side Movie. Study Program of English, Department of Languages and Literature, Faculty of Culture Studies, Universitas Brawijaya. Supervisor: Dyah Eko Hapsari;Co-supervisor: Sarlettina Vidyayani EkaKeywords: Learned Helplessness, African-American, Psychological, Social Behavior, Depression, The Blind Side.Social behavior shows several interactions between person and social situations, which stress...

Hair-brane ideas on the horizon

International Nuclear Information System (INIS)

Martinec, Emil J.; Niehoff, Ben E.

2015-01-01

We continue an examination of the microstate geometries program begun in arXiv:1409.6017, focussing on the role of branes that wrap the cycles which degenerate when a throat in the geometry deepens and a horizon forms. An associated quiver quantum mechanical model of minimally wrapped branes exhibits a non-negligible fraction of the gravitational entropy, which scales correctly as a function of the charges. The results suggest a picture of AdS_3/CFT_2 duality wherein the long string that accounts for BTZ black hole entropy in the CFT description, can also be seen to inhabit the horizon of BPS black holes on the gravity side.

Hair-brane ideas on the horizon

Energy Technology Data Exchange (ETDEWEB)

Martinec, Emil J. [Enrico Fermi Institute and Department of Physics, University of Chicago, 5640 S. Ellis Ave., Chicago, IL 60637-1433 (United States); Niehoff, Ben E. [Department of Applied Mathematics and Theoretical Physics, University of Cambridge,Centre for Mathematical Sciences,Wilberforce Rd., Cambridge, CB3 0WA (United Kingdom)

2015-11-27

We continue an examination of the microstate geometries program begun in arXiv:1409.6017, focussing on the role of branes that wrap the cycles which degenerate when a throat in the geometry deepens and a horizon forms. An associated quiver quantum mechanical model of minimally wrapped branes exhibits a non-negligible fraction of the gravitational entropy, which scales correctly as a function of the charges. The results suggest a picture of AdS{sub 3}/CFT{sub 2} duality wherein the long string that accounts for BTZ black hole entropy in the CFT description, can also be seen to inhabit the horizon of BPS black holes on the gravity side.

From Gouldner to Gramsci: The Making of Michael Apple's "Ideology and Curriculum"

Science.gov (United States)

Gottesman, Isaac

2012-01-01

Michael Apple's "Ideology and Curriculum", published in 1979, helped initiate a broad turn in the field of education in the United States to Marxist thought as a lens through which to analyze the relationship between school and society. This classic text continues to inform scholarship in the field. While "Ideology" has…

Eocene volcanism and the origin of horizon A

Science.gov (United States)

Gibson, T.G.; Towe, K.M.

1971-01-01

A series of closely time-equivalent deposits that correlate with seismic reflector horizon A exists along the coast of eastern North America. These sediments of Late-Early to Early-Middle Eocene age contain an authigenic mineral suite indicative of the alteration of volcanic glass. A volcanic origin for these siliceous deposits onshore is consistent with a volcanic origin for the cherts of horizon A offshore.

Navigating Transition: Freedom, Limitation and the Post-colonial Persona in Michael Ondaatje's The Cat's Table

Directory of Open Access Journals (Sweden)

Alaa Alghamdi

2012-11-01

Full Text Available Michael Ondaatje's 2011 novel The Cat's Table follows a young boy's voyage from Colombo, Sri Lanka to London, England. Through this character and the unique environment of the ship, which forms a compelling sense of transitory place, Ondaatje explores liminality and its relationship with limitations or barriers. The young protagonist, Michael, and his companions enjoy an unusual level of freedom aboard the contained and hierarchically segmented ship. Polarization and transition between Eastern and Western culture is present but pales in importance compared to the validation of the self that is located within and defined by the sense of the in-between, an essential rite of passage undertaken before re-joining society.

Event and Apparent Horizon Finders for 3+1 Numerical Relativity

Directory of Open Access Journals (Sweden)

Thornburg Jonathan

2007-06-01

Full Text Available Event and apparent horizons are key diagnostics for the presence and properties of black holes. In this article I review numerical algorithms and codes for finding event and apparent horizons in numerically-computed spacetimes, focusing on calculations done using the 3+1 ADM formalism. The event horizon of an asymptotically-flat spacetime is the boundary between those events from which a future-pointing null geodesic can reach future null infinity and those events from which no such geodesic exists. The event horizon is a (continuous null surface in spacetime. The event horizon is defined nonlocally in time: it is a global property of the entire spacetime and must be found in a separate post-processing phase after all (or at least the nonstationary part of spacetime has been numerically computed.There are three basic algorithms for finding event horizons, based on integrating null geodesics forwards in time, integrating null geodesics backwards in time, and integrating null surfaces backwards in time. The last of these is generally the most efficient and accurate.In contrast to an event horizon, an apparent horizon is defined locally in time in a spacelike slice and depends only on data in that slice, so it can be (and usually is found during the numerical computation of a spacetime. A marginally outer trapped surface (MOTS in a slice is a smooth closed 2-surface whose future-pointing outgoing null geodesics have zero expansion Theta. An apparent horizon is then defined as a MOTS not contained in any other MOTS. The MOTS condition is a nonlinear elliptic partial differential equation (PDE for the surface shape, containing the ADM 3-metric, its spatial derivatives, and the extrinsic curvature as coefficients. Most “apparent horizon” finders actually find MOTSs.There are a large number of apparent horizon finding algorithms, with differing trade-offs between speed, robustness, accuracy, and ease of programming. In axisymmetry, shooting

Horizon thermodynamics and gravitational field equations in Horava-Lifshitz gravity

International Nuclear Information System (INIS)

Cai Ronggen; Ohta, Nobuyoshi

2010-01-01

We explore the relationship between the first law of thermodynamics and gravitational field equation at a static, spherically symmetric black hole horizon in Horava-Lifshitz theory with/without detailed balance. It turns out that as in the cases of Einstein gravity and Lovelock gravity, the gravitational field equation can be cast to a form of the first law of thermodynamics at the black hole horizon. This way we obtain the expressions for entropy and mass in terms of black hole horizon, consistent with those from other approaches. We also define a generalized Misner-Sharp energy for static, spherically symmetric spacetimes in Horava-Lifshitz theory. The generalized Misner-Sharp energy is conserved in the case without matter field, and its variation gives the first law of black hole thermodynamics at the black hole horizon.

Robust Consumption-Investment Problem on Infinite Horizon

Energy Technology Data Exchange (ETDEWEB)

Zawisza, Dariusz, E-mail: dariusz.zawisza@im.uj.edu.pl [Jagiellonian University in Krakow, Institute of Mathematics, Faculty of Mathematics and Computer Science (Poland)

2015-12-15

In our paper we consider an infinite horizon consumption-investment problem under a model misspecification in a general stochastic factor model. We formulate the problem as a stochastic game and finally characterize the saddle point and the value function of that game using an ODE of semilinear type, for which we provide a proof of an existence and uniqueness theorem for its solution. Such equation is interested on its own right, since it generalizes many other equations arising in various infinite horizon optimization problems.

Isoindolinones as Michael Donors under Phase Transfer Catalysis: Enantioselective Synthesis of Phthalimidines Containing a Tetrasubstituted Carbon Stereocenter

Directory of Open Access Journals (Sweden)

Francesco Scorzelli

2015-05-01

Full Text Available Readily available chiral ammonium salts derived from cinchona alkaloids have proven to be effective phase transfer catalysts in the asymmetric Michael reaction of 3-substituted isoindolinones. This protocol provides a convenient method for the construction of valuable asymmetric 3,3-disubstituted isoindolinones in high yields and  moderate to good enantioselectivity. Diastereoselectivity was also investigated in the construction of contiguous tertiary and quaternary stereocenters. The use of acrolein as Michael acceptor led to an interesting tricyclic derivative, a pyrroloisoindolinone analogue, via a tandem conjugated addition/cyclization reaction.

Neighborhoods of Cauchy horizons in cosmological spacetimes with one killing field

International Nuclear Information System (INIS)

Moncrief, V.

1982-01-01

In this paper we show how to construct an infinite dimensional family of analytic, vacuum spacetimes which each have (i) T 3 x R topology, (ii) a smooth, compact Cauchy horizon, and (iii) a single Killing vector field which is spacelike in the globally hyperbolic region, null on the horizon and timelike in the (acausal) extension. The key idea is to use the horizons themselves as initial data surfaces and to prove the local existence of solutions using a version of the Cauchy-Kowalewski theorem. Factoring by the action of analytic, horizon preserving diffeomorphisms we define a ''space of extendible vacuum spacetimes'' of the given symmetry type and show (modulo certain smoothness estimates which we do not attempt to derive) that this space defines a Lagrangian submanifold of the usual phase space for Einstein's equations. We also study the linear perturbations of a class of the extendible spacetimes and show that the generic such perturbation blows up near the background solution's Cauchy horizon. This result, though limited by the linearity of the approximation, conforms to the usual picture of unstable Cauchy horizons demanded by the strong cosmic censorship conjecture

SYNTHESIS OF SOME PROLINE DERIVATIVES BY MEANS OF MICHAEL ADDITIONS OF GLYCINE ESTERS

NARCIS (Netherlands)

VANDERWERF, A; KELLOGG, RM

1991-01-01

Addition of the Schiff bases derived from reaction of glycine alkyl esters with benzophenoneimine to alpha,beta-unsaturated ketones, followed by hydrogenation of the addition products, leads to 5- or 3,5-substituted prolines. Hydrolysis of the Michael adducts rather than hydrogenation allows

Tõsine fotoelamus Dubrovnikus / Wade Goddard, Heidi Levine, Michael Robinson Chaver ; interv. Ahto Külvet

Index Scriptorium Estoniae

Goddard, Wade

2007-01-01

Dubrovniku vanalinnas asub Sõjafotokeskus. Intervjuu keskuse asutaja, kanadalasest fotograafi Wade Goddardi ja kahe seal augustis avatud näitusel osalenud fotograafi Heidi Levine'i ja Michael Robinson Chavez'iga. Sõjafotograafi tööst

Quantum horizon fluctuations of an evaporating black hole

International Nuclear Information System (INIS)

Roura, Albert

2007-01-01

The quantum fluctuations of a black hole spacetime are studied within a low-energy effective field theory approach to quantum gravity. Our approach accounts for both intrinsic metric fluctuations and those induced by matter fields interacting with the gravitational field. Here we will concentrate on spherically symmetric fluctuations of the black hole horizon. Our results suggest that for a sufficiently massive evaporating black hole, fluctuations can accumulate over time and become significant well before reaching Planckian scales. In addition, we provide the sketch of a proof that the symmetrized two-point function of the stress-tensor operator smeared over a null hypersurface is actually divergent and discuss the implications for the analysis of horizon fluctuations. Finally, a natural way to probe quantum metric fluctuations near the horizon is briefly described

Thermodynamics of event horizons in (2+1)-dimensional gravity

International Nuclear Information System (INIS)

Reznik, B.

1992-01-01

Although gravity in 2+1 dimensions is very different in nature from gravity in 3+1 dimensions, it is shown that the laws of thermodynamics for event horizons can be manifested also for (2+1)-dimensional gravity. The validity of the classical laws of horizon mechanics is verified in general and exemplified for the (2+1)-dimensional analogues of Reissner-Nordstroem and Schwarzschild--de Sitter spacetimes. We find that the entropy is given by 1/4L, where L is the length of the horizon. A consequence of having consistent thermodynamics is that the second law fixes the sign of Newton's constant to be positive

Stringy horizons II

Energy Technology Data Exchange (ETDEWEB)

Giveon, Amit [Racah Institute of Physics, The Hebrew University,Jerusalem 91904 (Israel); Itzhaki, Nissan [Physics Department, Tel-Aviv University,Ramat-Aviv, 69978 (Israel); Kutasov, David [EFI and Department of Physics, University of Chicago,5640 S. Ellis Av., Chicago, IL 60637 (United States)

2016-10-28

We show that the spectrum of normalizable states on a Euclidean SL(2, R)/U(1) black hole exhibits a duality between oscillator states and wound strings. This duality generalizes the identification between a normalizable mode of dilaton gravity on the cigar and a mode of the tachyon with winding number one around the Euclidean time circle, which plays an important role in the FZZ correspondence. It implies that normalizable states on a large Euclidean black hole have support at widely separated scales. In particular, localized states that are extended over the cap of the cigar (the Euclidian analog of the black hole atmosphere) have a component that is localized near the tip of the cigar (the analog of the stretched horizon). As a consequence of this duality, the states exhibit a transition as a function of radial excitation level. From the perspective of a low energy probe, low lying states are naturally thought of as oscillator states in the black hole atmosphere, while at large excitation level they are naturally described as wound strings. As the excitation level increases, the size of the states first decreases and then increases. This behavior is expected to be a general feature of black hole horizons in string theory.

Production of Low-Freezing-Point Highly Branched Alkanes through Michael Addition.

Science.gov (United States)

Jing, Yaxuan; Xia, Qineng; Liu, Xiaohui; Wang, Yanqin

2017-12-22

A new approach for the production of low-freezing-point, high-quality fuels from lignocellulose-derived molecules was developed with Michael addition as the key step. Among the investigated catalysts, CoCl 2 ⋅6 H 2 O was found most active for the Michael addition of 2,4-pentanedione with FA (single aldol adduct of furfural and acetone, 4-(2-furanyl)-3-butene-2-one). Over CoCl 2 ⋅6 H 2 O, a high carbon yield of C 13 oxygenates (about 75 %) can be achieved under mild conditions (353 K, 20 h). After hydrodeoxygenation, low-freezing-point (hydrodeoxygenation, high density (0.8415 g mL -1 ) and low-freezing-point (<223 K) branched alkanes with 18, 23 carbons within lubricant range were also obtained over a Pd/NbOPO 4 catalyst. These highly branched alkanes can be directly used as transportation fuels or additives. This work opens a new strategy for the synthesis of highly branched alkanes with low freezing point from renewable biomass. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quantization of horizon entropy and the thermodynamics of spacetime

International Nuclear Information System (INIS)

Skakala, Jozef

2014-01-01

This is a review of my work published in the papers of Skakala (JHEP 1201:144, 2012; JHEP 1206:094, 2012) and Chirenti et al. (Phys. Rev. D 86:124008, 2012; Phys. Rev.D 87:044034, 2013). It offers a more detailed discussion of the results than the accounts in those papers, and it links my results to some conclusions recently reached by other authors. It also offers some new arguments supporting the conclusions in the cited articles. The fundamental idea of this work is that the semiclassical quantization of the black hole entropy, as suggested by Bekenstein (Phys. Rev. D 7:2333-2346, 1973), holds (at least) generically for the spacetime horizons. We support this conclusion by two separate arguments: (1) we generalize Bekenstein’s lower bound on the horizon area transition to a much wider class of horizons than only the black-hole horizon, and (2) we obtain the same entropy spectra via the asymptotic quasi-normal frequencies of some particular spherically symmetric multi horizon spacetimes (in the way proposed by Maggiore (Phys. Rev. Lett. 100:141301, 2008)). The main result of this paper supports the conclusions derived by Kothawalla et al. (Phys. Rev. D 78:104018, 2008) and Kwon and Nam (Class. Quant. Grav. 28:035007, 2011), on the basis of different arguments. (author)

The Correspondence of Michael Faraday Pt 6 1860-1867

CERN Document Server

Frank, James

2012-01-01

Michael Faraday (1791-1867) was one of the most important men of science in nineteenth century Britain. His discoveries of electro-magnetic rotations (1821) and electro-magnetic induction (1831) laid the foundations of the modern electrical industry. His discovery of the magneto-optical effect and diamagnetism (1845) led him to formulate the field theory of electro-magnetism, which forms one of the cornerstones of modern physics.These and a whole host of other fundamental discoveries in physics and chemistry, together with his lecturing at the Royal Institution, his work for the state (includi

Properties of global monopoles with an event horizon

OpenAIRE

Tamaki, T; Sakai, N

2004-01-01

We investigate the properties of global monopoles with an event horizon. We find that there is an unstable circular orbit even if a particle does not have an angular momentum when the core mass is negative. We also obtain the asymptotic form of solutions when the event horizon is much larger than the core radius of the monopole, and discuss if they could be a model of galactic halos.

Supertranslations and Superrotations at the Black Hole Horizon.

Science.gov (United States)

Donnay, Laura; Giribet, Gaston; González, Hernán A; Pino, Miguel

2016-03-04

We show that the asymptotic symmetries close to nonextremal black hole horizons are generated by an extension of supertranslations. This group is generated by a semidirect sum of Virasoro and Abelian currents. The charges associated with the asymptotic Killing symmetries satisfy the same algebra. When considering the special case of a stationary black hole, the zero mode charges correspond to the angular momentum and the entropy at the horizon.

Kunstlik viljastamine - kas rahva püsimajäämise võti? / Michael Cook

Index Scriptorium Estoniae

Cook, Michael

2007-01-01

Kunstlikust viljastamisest pole üksi abi - vaid siis, kui noored mehed ja naised pööravad selja tarbimiskultusele ja individualismile, hakkab sündimus tõusma taastootmisest kõrgemale, kirjutab BioEdge toimetaja Michael Cook

New Horizons Pluto Flyby Guest Operations

Science.gov (United States)

Simon, M.; Turney, D.; Fisher, S.; Carr, S. S.

2015-12-01

On July 14, 2015, after 9.5 years of cruise, NASA's New Horizons spacecraft flew past the Pluto system to gather first images humankind had ever seen on Pluto and its five moons. While much has been discovered about the Pluto system since New Horizons launch in 2006, the system has never been imaged at high resolution and anticipation of the "First Light" of the Pluto system had been anticipated by planetary enthusiasts for decades. The Johns Hopkins Applied Physics Laboratory (APL), which built and operates New Horizons, was the focal point for gathering three distinct groups: science and engineering team members; media and public affairs representatives; and invited public, including VIP's. Guest operations activities were focused on providing information primarily to the invited public and VIP's. High level objectives for the Guest Operations team was set to entertain and inform the general public, offer media reaction shots, and to deconflict activities for the guests from media activities wherever possible. Over 2000 people arrived at APL in the days surrounding closest approach for guest, science or media operations tracks. Reaction and coverage of the Guest Operations events was universally positive and global in impact: iconic pictures of the auditorium waving flags during the moment of closest approach were published in media outlets on every continent. Media relations activities ensured coverage in all key media publications targeted for release, such as the New York Times, Science, Le Monde, and Nature. Social and traditional media coverage of the events spanned the globe. Guest operations activities are designed to ensure that a guest has a memorable experience and leaves with a lifelong memory of the mission and their partnership in the activity. Results, lessons learned, and other data from the New Horizons guest operations activity will be presented and analyzed.

Vacuum non-expanding horizons and shear-free null geodesic congruences

International Nuclear Information System (INIS)

Adamo, T M; Newman, E T

2009-01-01

We investigate the geometry of a particular class of null surfaces in spacetime called vacuum non-expanding horizons (NEHs). Using the spin-coefficient equation, we provide a complete description of the horizon geometry, as well as fixing a canonical choice of null tetrad and coordinates on a NEH. By looking for particular classes of null geodesic congruences which live exterior to NEHs but have the special property that their shear vanishes at the intersection with the horizon, a good cut formalism for NEHs is developed which closely mirrors asymptotic theory. In particular, we show that such null geodesic congruences are generated by arbitrary choice of a complex worldline in a complex four-dimensional space, each such choice induces a CR structure on the horizon, and a particular worldline (and hence CR structure) may be chosen by transforming to a privileged tetrad frame.

Eesti disain on kõva, ent see tuleb moondada ekspordiks / Michael Thomson ; interv. Urmas Oja

Index Scriptorium Estoniae

Thomson, Michael

2008-01-01

Euroopa Disainiassotsiatsioonide Liidu presidendi ja Tallinnas toimunud festivali Disainiöö Eesti disainiauhinna Bruno žürii juhi Michael Thomsoni arvamus eesti disainist ning disainipoliitika vajalikkusest Eestis. Auhinnasaajate nimekiri

Killing Horizons as Equipotential Hypersurfaces

OpenAIRE

Smolić, Ivica

2012-01-01

In this note we present a new proof that Killing horizons are equipotential hypersurfaces for the electric and the magnetic scalar potential, that makes no use of gravitational field equations or the assumption about the existence of bifurcation surface.

Compassionate leadership? Some reflections on the work and life of Michael Lapsley

Directory of Open Access Journals (Sweden)

Ian A. Nell

2016-03-01

Full Text Available In June 2007, I had the privilege of attending a Healing of Memories workshop lead by Father Michael Lapsley, one of the founder members of the Institute for Healing of Memories. The purpose of the workshop was to help the predominantly white members of a middle class Dutch Reformed congregation in the Northern Suburbs of Cape Town and the predominantly coloured members of a congregation of the Evangelical Lutheran Church in Elsies River on the Cape Flats, to share their stories of the past with regard to apartheid with each other. Apart from the stories that were told and the sharing of experiences about the apartheid history that took place, I was struck by the way in which Father Lapsley conducted the workshop. There was a deep compassion for all the participants as was embodied through the way in which he treated each of us with respect. But apart from his cordiality in leading the workshop, one could sense a deeper source of compassion, a source revealing a compassionate understanding of God�s presence amidst the violence and turmoil in our broken world. The aim of this article is to reflect on whether one could speak of something like �compassionate leadership�, and to take a closer look at the relationship between compassion and God images in the life and work of Michael Lapsley. Special attention will be given to the way in which he exercises leadership through his many involvements related to his own personal story of trauma.Intradisciplinary and/or interdisciplinary implications: This article presents literary research on the notion of compassionate leadership as a specific kind of leadership. The results indicate that the leadership of Father Michael Lapsley does indeed portray features of this kind of leadership. The research can become the source for finding new strategies for religious leadership.

Killing horizons as equipotential hypersurfaces

International Nuclear Information System (INIS)

Smolić, Ivica

2012-01-01

In this note we present a new proof that Killing horizons are equipotential hypersurfaces for the electric and the magnetic scalar potential, which makes no use of gravitational field equations or the assumption about the existence of a bifurcation surface. (note)

Isolated and Dynamical Horizons and Their Applications

Directory of Open Access Journals (Sweden)

Ashtekar Abhay

2004-12-01

Full Text Available Over the past three decades, black holes have played an important role in quantum gravity, mathematical physics, numerical relativity and gravitational wave phenomenology. However, conceptual settings and mathematical models used to discuss them have varied considerably from one area to another. Over the last five years a new, quasi-local framework was introduced to analyze diverse facets of black holes in a unified manner. In this framework, evolving black holes are modelled by dynamical horizons and black holes in equilibrium by isolated horizons. We review basic properties of these horizons and summarize applications to mathematical physics, numerical relativity, and quantum gravity. This paradigm has led to significant generalizations of several results in black hole physics. Specifically, it has introduced a more physical setting for black hole thermodynamics and for black hole entropy calculations in quantum gravity, suggested a phenomenological model for hairy black holes, provided novel techniques to extract physics from numerical simulations, and led to new laws governing the dynamics of black holes in exact general relativity.

Interviews with Michael Baxandall, February 3rd and 4th, 1994, Berkeley, CA

Directory of Open Access Journals (Sweden)

Allan Langdale

2009-12-01

Full Text Available The following interviews with Michael Baxandall were conducted in Berkeley on February 3rd and 4th of 1994. The content of these interviews include general responses about developments in art history in the years between 1960 and 1985, a period of dramatic modifications in the discipline. Among the issues are the rise of the social history of art and the sources from anthropology that informed Baxandall’s concept of the ‘Period Eye’. Baxandall talks about his own work, his personal intellectual history, and the scholars of past and current generations who influenced him. Other topics include Baxandall’s professional trajectory, the Warburg Library, and aspects of cultural history having to do with Renaissance Humanism. These interviews first appeared as an appendix to the PhD dissertation by Allan Langdale, Art History and Intellectual History: Michael Baxandall’s Work between 1963 and 1985, U. C. Santa Barbara, 1995.

Earth, Meet Pluto: The New Horizons Education and Communications Partnership

Science.gov (United States)

Buckley, M.

2015-12-01

The unique partnership between the NASA New Horizons education/communications and public affairs programs tapped into the excitement of visiting an unexplored planet in a new region of the solar system - resulting in unprecedented public participation in and coverage of a planetary mission. With a range of hands-on learning experiences, Web materials and online , the program provided opportunities for students, educators, museums, science centers, the media, Web surfers and other members of the public to ride along on the first mission to Pluto and the Kuiper Belt. The programs leveraged resources, materials and expertise to address a wide range of traditional and nontraditional audiences while providing consistent messages and information on this historic NASA endeavor. The E/C program included a variety of formal lesson plans and learning materials — based on New Horizons science and engineering goals, and aligned with National Research Council's National Science Education Standards — that continue to help students in grades K-12 learn more about science, technology, engineering and mathematics. College students designed and built an actual flight instrument on New Horizons and held internships with the spacecraft integration and test team. New Horizons E/C programs went well beyond the classroom, from a chance for people to send their names to Pluto on board the New Horizons spacecraft before launch, to opportunities for the public to access milestone events and the first-ever close-up views of Pluto in places such as museums, science centers and libraries, TV and the Web — as well as thousands who attended interactive "Plutopalooza" road shows across the country. Teamed with E/C was the public affairs strategy to communicate New Horizons news and messages to media, mission stakeholders, the scientific community and the public. These messages include various aspects of New Horizons, including the progress of the mission and key milestones and achievements

Michael Maier--nine newly discovered letters.

Science.gov (United States)

Lenke, Nils; Roudet, Nicolas; Tilton, Hereward

2014-02-01

The authors provide a transcription, translation, and evaluation of nine newly discovered letters from the alchemist Michael Maier (1568-1622) to Gebhardt Johann von Alvensleben (1576-1631), a noble landholder in the vicinity of Magdeburg. Stemming from the final year of his life, this correspondence casts new light on Maier's biography, detailing his efforts to secure patronage amid the financial crisis of the early Thirty Years' War. While his ill-fated quest to perfect potable gold continued to form the central focus of his patronage suits, Maier also offered his services in several arts that he had condemned in his printed works, namely astrology and "supernatural" magic. Remarks concerning his previously unknown acquaintance with Heinrich Khunrath call for a re-evaluation of Maier's negotiation of the discursive boundaries between Lutheran orthodoxy and Paracelsianism. The letters also reveal Maier's substantial contribution to a work previously ascribed solely to the English alchemist Francis Anthony.

Geometric properties of magnetized black hole event horizons and ergosurfaces

International Nuclear Information System (INIS)

Esteban, E P

2009-01-01

In this paper we focus in the geometric properties of the magnetized Kerr-Newman metric. Three applications are considered. First, the event horizon surface area is calculated and from there we derive the first law of thermodynamics for magnetized black holes. We have obtained analytical expressions for the surface gravity, angular velocity, electric potential, and magnetic moment at the magnetized Kerr-Newman black hole event horizon. An approximate expression for the surface area of the magnetized black hole ergosurface was also obtained. Second, we study the magnetized Kerr-Newman black hole's circumferences. We found that for small values of the angular momentum the event horizon has a prolate spheroid shape. Increasing the value of the angular momentum will change the event horizon shape from a prolate ellipsoid to an oblate spheroid. For small values of the angular momentum and charge the ergosurface shape is an oblate spheroid. Increasing these two parameters will change the ergosurface shape from a oblate spheroid to a prolate spheroid. Third, analytical expressions for the magnetized Kerr-Newman event horizon and ergosurface Gaussian curvatures were obtained although not explicitly shown. Instead a graphical analysis was carried out to visualize regions where Gaussian curvatures take negative or positive values. We found that the Gaussian curvature at the event horizon poles has negative values and do not satisfy Pelavas condition. Therefore, these regions can not be embedded in E 3 . However, the magnetized Kerr-Newman ergosurface can be embedded in E 3 regardless the negative Gaussian curvature values in some regions of the ergosurface.

Implication of Negative Temperature in the Inner Horizon of Reissner-Nordström Black Hole

Directory of Open Access Journals (Sweden)

Yuant Tiandho

2017-12-01

Full Text Available This paper reconsiders the properties of Hawking radiation in the inner horizon of a Reissner-Nordström black hole. Through the correlation between temperature and surface gravity, it is concluded that the temperature of the inner horizon is always negative and that of the outer horizon is always positive. Since negative temperature is hotter than any positive temperature, it is predicted that particle radiation from the inner horizon will move toward the outer horizon. However, unlike temperature, entropy in both horizons remains positive. Following the definition of negative temperature in the inner horizon, it is assured that the entropy of a black hole within a closed system can never decrease. By analyzing the conditions of an extremal black hole, the third law of black hole thermodynamics can be extended to multi-horizon black holes.

Tunneling from the past horizon

Science.gov (United States)

Kang, Subeom; Yeom, Dong-han

2018-04-01

We investigate a tunneling and emission process of a thin-shell from a Schwarzschild black hole, where the shell was initially located beyond the Einstein-Rosen bridge and finally appears at the right side of the Penrose diagram. In order to obtain such a solution, we should assume that the areal radius of the black hole horizon increases after the tunneling. Hence, there is a parameter range such that the tunneling rate is exponentially enhanced, rather than suppressed. We may have two interpretations regarding this. First, such a tunneling process from the past horizon is improbable by physical reasons; second, such a tunneling is possible in principle, but in order to obtain a stable Einstein-Rosen bridge, one needs to restrict the parameter spaces. If such a process is allowed, this can be a nonperturbative contribution to Einstein-Rosen bridges as well as eternal black holes.

Political Cinema and Culture industry: the work of Michael Moore

OpenAIRE

Cristiane Toledo Maria

2015-01-01

This article aims to reflect upon the production of the American filmmaker Michael Moore, proposing as a central question the relationship established between art and politics in a historical moment which, on one side, points to the crisis of capitalism and, on the other side, to the political fragmentation of the working class. Focusing on the analysis of the documentaries Roger & Me (1989) and Capitalism: a love story (2009), this article is an attempt to understand the method developed by ...

Nearly extremal apparent horizons in simulations of merging black holes

Science.gov (United States)

Lovelace, Geoffrey; Scheel, Mark; Owen, Robert; Giesler, Matthew; Katebi, Reza; Szilagyi, Bela; Chu, Tony; Demos, Nicholas; Hemberger, Daniel; Kidder, Lawrence; Pfeiffer, Harald; Afshari, Nousha; SXS Collaboration

2015-04-01

The spin S of a Kerr black hole is bounded by the surface area A of its apparent horizon: 8 πS A and e0 > 1 , but these surfaces are always surrounded by apparent horizons with 8 πS < A and e0 < 1 .

Estratégia competitiva: Michael Porter 30 anos depois

Directory of Open Access Journals (Sweden)

Manuel Portugal Ferreira

2009-12-01

Full Text Available Os estudos de estratégia têm sido muito influenciados pelos trabalhos de Michael Porter, em todas as suas fases, como as cinco forças, as estratégias genéricas, a cadeia de valor e as vantagens competitivas das nações. Neste artigo, analisou-se a influência de Porter nos trabalhos brasileiros em estratégia, a partir dos trabalhos selecionados e apresentados no EnANPAD. No levantamento para a análise dos artigos, considerando 10 anos de EnANPAD (1997-2006, foram selecionados 46 artigos. A identificação e seleção dos artigos envolveram os seguintes critérios: busca complementar por palavra-chave Porter na base de dados do EnANPAD; avaliação dos títulos e resumos dos artigos apresentados na área de estratégia entre 1997 e 2006, bem como na íntegra quando necessário. Procedeu-se também à análise das referências utilizadas nos artigos e o posicionamento dos autores em relação às tipologias de Porter. Como resultado, verificou-se que Michael Porter é um autor com grande influência nas pesquisas acadêmicas de estratégia. Seus estudos mais utilizados são os da análise da indústria e das estratégias genéricas, e também se verificou que a maioria dos estudos analisados é favorável aos seus conceitos, mesmo existindo pesquisas contrárias.

Losing Information Outside the Horizon

Directory of Open Access Journals (Sweden)

Samir D. Mathur

2015-06-01

Full Text Available Suppose we allow a system to fall freely from infinity to a point near (but not beyond the horizon of a black hole. We note that in a sense the information in the system is already lost to an observer at infinity. Once the system is too close to the horizon it does not have enough energy to send its information back because the information carrying quanta would get redshifted to a point where they get confused with Hawking radiation. If one attempts to turn the infalling system around and bring it back to infinity for observation then it will experience Unruh radiation from the required acceleration. This radiation can excite the bits in the system carrying the information, thus reducing the fidelity of this information. We find the radius where the information is essentially lost in this way, noting that this radius depends on the energy gap (and coupling of the system. We look for some universality by using the highly degenerate BPS ground states of a quantum gravity theory (string theory as our information storage device. For such systems one finds that the critical distance to the horizon set by Unruh radiation is the geometric mean of the black hole radius and the radius of the extremal hole with quantum numbers of the BPS bound state. Overall, the results suggest that information in gravity theories should be regarded not as a quantity contained in a system, but in terms of how much of this information is accessible to another observer.

Isolated, slowly evolving, and dynamical trapping horizons: Geometry and mechanics from surface deformations

International Nuclear Information System (INIS)

Booth, Ivan; Fairhurst, Stephen

2007-01-01

We study the geometry and dynamics of both isolated and dynamical trapping horizons by considering the allowed variations of their foliating two-surfaces. This provides a common framework that may be used to consider both their possible evolutions and their deformations as well as derive the well-known flux laws. Using this framework, we unify much of what is already known about these objects as well as derive some new results. In particular we characterize and study the ''almost isolated'' trapping horizons known as slowly evolving horizons. It is for these horizons that a dynamical first law holds and this is analogous and closely related to the Hawking-Hartle formula for event horizons

Genetics, genomes and cloning the biotechnology revolution

CERN Document Server

CERN. Geneva

1999-01-01

As this century draws to a close, spectacular advances in the fields of genomics and genetics are opening up dramatic new horizons for medicine. For much of the 20th century, genetic research has focused on rare diseases caused by mutations in a particular gene. However, more recently it has been realised that common genetic variations (polymorphisms), interacting with the environment, can influence an individual's susceptibility to diseases widely represented in our populations (e.g. mental illness and asthma), redefining the term "genetic disease". Officially starting in 1990, the Human Genome Project was a $3-billion, 15-year program to find the estimated 80,000 human genes and determine the sequence of the 3 billion DNA building blocks that underlie all of human biology and its diversity. The resulting boom in genetic information and technologies, not only from humans, but from many other organisms, means that we now have new tools to understand and treat normal and disease states. This information is bei...

Static Isolated Horizons: SU(2 Invariant Phase Space, Quantization, and Black Hole Entropy

Directory of Open Access Journals (Sweden)

Alejandro Perez

2011-03-01

Full Text Available We study the classical field theoretical formulation of static generic isolated horizons in a manifestly SU(2 invariant formulation. We show that the usual classical description requires revision in the non-static case due to the breaking of diffeomorphism invariance at the horizon leading to the non-conservation of the usual pre-symplectic structure. We argue how this difficulty could be avoided by a simple enlargement of the field content at the horizon that restores diffeomorphism invariance. Restricting our attention to static isolated horizons we study the effective theories describing the boundary degrees of freedom. A quantization of the horizon degrees of freedom is proposed. By defining a statistical mechanical ensemble where only the area aH of the horizon is fixed macroscopically—states with fluctuations away from spherical symmetry are allowed—we show that it is possible to obtain agreement with the Hawkings area law (S = aH /(4l 2p without fixing the Immirzi parameter to any particular value: consistency with the area law only imposes a relationship between the Immirzi parameter and the level of the Chern-Simons theory involved in the effective description of the horizon degrees of freedom.

Conditions for characterizing the structure of optimal strategies in infinite-horizon dynamic programs

International Nuclear Information System (INIS)

Porteus, E.

1982-01-01

The study of infinite-horizon nonstationary dynamic programs using the operator approach is continued. The point of view here differs slightly from that taken by others, in that Denardo's local income function is not used as a starting point. Infinite-horizon values are defined as limits of finite-horizon values, as the horizons get long. Two important conditions of an earlier paper are weakened, yet the optimality equations, the optimality criterion, and the existence of optimal ''structured'' strategies are still obtained

Approximate Receding Horizon Approach for Markov Decision Processes: Average Award Case

National Research Council Canada - National Science Library

Chang, Hyeong S; Marcus, Steven I

2002-01-01

...) with countable state space, finite action space, and bounded rewards that uses an approximate solution of a fixed finite-horizon sub-MDP of a given infinite-horizon MDP to create a stationary policy...

Noted astrophysicist Michael S. Turner to Head NSF'S mathematical and physical sciences directorate

CERN Multimedia

2003-01-01

"The National Science Foundation has named celebrated astrophysicist Michael S. Turner of the University of Chicago as Assistant Director for Mathematical and Physical Sciences. He will head a $1 billion directorate that supports research in mathematics, physics, chemistry, materials and astronomy, as well as multidisciplinary programs and education" (1/2 page).

Dignital Biological Converter

Science.gov (United States)

2014-01-03

DARPA Contracting Officer: Michael Blackstone Submitted by: HEATHER GOUVIS Synthetic Genomics, Inc. 11149 NORTH TORREY PINES RD LA JOLLA, CA...Contracting Officer Representative (COR) Email: salit@nist.gov Michael Blackstone DARPA Contracting Officer Michael.Blackstone@darpa.mil DARPA

Hexafluorobenzene: A powerful solvent for a noncovalent stereoselective organocatalytic Michael addition reaction

KAUST Repository

Lattanzi, Alessandra

2012-01-01

A dramatic enhancement of the diastereo- and enantioselectivity in the nitro-Michael addition reaction organocatalysed by a commercially available α,α-l-diaryl prolinol was disclosed when performing the reaction in unconventional hexafluorobenzene as a medium. DFT calculations were performed to clarify the origin of stereoselectivity and the role of C 6F 6. © The Royal Society of Chemistry 2012.

Feeding Health: Michael Pollan on Improving Public Health through the Food Systems

Centers for Disease Control (CDC) Podcasts

2009-08-19

In this podcast, author Michael Pollan discusses his March 2009 visit to CDC and offers his thoughts on the intersection between the government, the food systems, and public health.  Created: 8/19/2009 by National Center for Environmental Health (NCEH), National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP), Office of Sustainability.   Date Released: 4/15/2010.

“This fabulous flotsam”: Michael Moorcock’s Urban Anthropology in “London under London”

Directory of Open Access Journals (Sweden)

Houswitschka Christoph

2015-07-01

Full Text Available Michael Moorcock is often described as “one of the most prolific and varied writers working in Britain” (Malcolm 146. His success as a writer and editor of science fiction and fantasy literature is well established, but he is also the author of two novels about London, Mother London (1988 and King of the City (2000. Hardly known, Mother London by Michael Moorcock, offers itself to a variety of approaches that have been widely discussed in the context of studies on English literature during the Thatcher years, post-modernism, and psycho-geography. The novel resonates with the author’s own childhood in war-time London without being autobiographical. It tells the story of three Londoners who were traumatised during the Blitz. The following article focuses on the mysteries of subterranean London that represents the hidden and unconscious identities of its inhabitants in the post-war period.

Michael Marinov memorial volume multiple facets of quantization and supersymmetry

CERN Document Server

Vainshtein, A I

2002-01-01

This book is dedicated to the memory of Michael Marinov, the theorist who, together with Felix Berezin, introduced the classical description of spin by anticommuting Grassmann variables. It contains original papers and reviews by physicists and mathematicians written specifically for the book. These articles reflect the current status and recent developments in the areas of Marinov's research: quantum tunneling, quantization of constrained systems, supersymmetry, and others. The personal recollections included portray the human face of M Marinov, a person of great knowledge and integrity.

Nitrate retention capacity of milldam-impacted legacy sediments and relict A horizon soils

Directory of Open Access Journals (Sweden)

J. N. Weitzman

2017-05-01

Full Text Available While eutrophication is often attributed to contemporary nutrient pollution, there is growing evidence that past practices, like the accumulation of legacy sediment behind historic milldams, are also important. Given their prevalence, there is a critical need to understand how N flows through, and is retained in, legacy sediments to improve predictions and management of N transport from uplands to streams in the context of climatic variability and land-use change. Our goal was to determine how nitrate (NO3− is cycled through the soil of a legacy-sediment-strewn stream before and after soil drying. We extracted 10.16 cm radius intact soil columns that extended 30 cm into each of the three significant soil horizons at Big Spring Run (BSR in Lancaster, Pennsylvania: surface legacy sediment characterized by a newly developing mineral A horizon soil, mid-layer legacy sediment consisting of mineral B horizon soil and a dark, organic-rich, buried relict A horizon soil. Columns were first preincubated at field capacity and then isotopically labeled nitrate (15NO3− was added and allowed to drain to estimate retention. The columns were then air-dried and subsequently rewet with N-free water and allowed to drain to quantify the drought-induced loss of 15NO3− from the different horizons. We found the highest initial 15N retention in the mid-layer legacy sediment (17 ± 4 % and buried relict A soil (14 ± 3 % horizons, with significantly lower retention in the surface legacy sediment (6 ± 1 % horizon. As expected, rewetting dry soil resulted in 15N losses in all horizons, with the greatest losses in the buried relict A horizon soil, followed by the mid-layer legacy sediment and surface legacy sediment horizons. The 15N remaining in the soil following the post-drought leaching was highest in the mid-layer legacy sediment, intermediate in the surface legacy sediment, and lowest in the buried relict A horizon soil. Fluctuations

Nitrate retention capacity of milldam-impacted legacy sediments and relict A horizon soils

Science.gov (United States)

Weitzman, Julie N.; Kaye, Jason P.

2017-05-01

While eutrophication is often attributed to contemporary nutrient pollution, there is growing evidence that past practices, like the accumulation of legacy sediment behind historic milldams, are also important. Given their prevalence, there is a critical need to understand how N flows through, and is retained in, legacy sediments to improve predictions and management of N transport from uplands to streams in the context of climatic variability and land-use change. Our goal was to determine how nitrate (NO3-) is cycled through the soil of a legacy-sediment-strewn stream before and after soil drying. We extracted 10.16 cm radius intact soil columns that extended 30 cm into each of the three significant soil horizons at Big Spring Run (BSR) in Lancaster, Pennsylvania: surface legacy sediment characterized by a newly developing mineral A horizon soil, mid-layer legacy sediment consisting of mineral B horizon soil and a dark, organic-rich, buried relict A horizon soil. Columns were first preincubated at field capacity and then isotopically labeled nitrate (15NO3-) was added and allowed to drain to estimate retention. The columns were then air-dried and subsequently rewet with N-free water and allowed to drain to quantify the drought-induced loss of 15NO3- from the different horizons. We found the highest initial 15N retention in the mid-layer legacy sediment (17 ± 4 %) and buried relict A soil (14 ± 3 %) horizons, with significantly lower retention in the surface legacy sediment (6 ± 1 %) horizon. As expected, rewetting dry soil resulted in 15N losses in all horizons, with the greatest losses in the buried relict A horizon soil, followed by the mid-layer legacy sediment and surface legacy sediment horizons. The 15N remaining in the soil following the post-drought leaching was highest in the mid-layer legacy sediment, intermediate in the surface legacy sediment, and lowest in the buried relict A horizon soil. Fluctuations in the water table at BSR which affect

Effective horizons, junction conditions and large-scale magnetism

Energy Technology Data Exchange (ETDEWEB)

Giovannini, Massimo [CERN, Department of Physics, Theory Division, Geneva (Switzerland); INFN, Milan (Italy)

2017-08-15

The quantum mechanical generation of hypermagnetic and hyperelectric fields in four-dimensional conformally flat background geometries rests on the simultaneous continuity of the effective horizon and of the extrinsic curvature across the inflationary boundary. The junction conditions for the gauge fields are derived in general terms and corroborated by explicit examples with particular attention to the limit of a sudden (but nonetheless continuous) transition of the effective horizon. After reducing the dynamics to a pair of integral equations related by duality transformations, we compute the power spectra and deduce a novel class of logarithmic corrections which turn out to be, however, numerically insignificant and overwhelmed by the conductivity effects once the gauge modes reenter the effective horizon. In this perspective the magnetogenesis requirements and the role of the postinflationary conductivity are clarified and reappraised. As long as the total duration of the inflationary phase is nearly minimal, quasi-flat hypermagnetic power spectra are comparatively more common than in the case of vacuum initial data. (orig.)

Horizon effects with surface waves on moving water

Energy Technology Data Exchange (ETDEWEB)

Rousseaux, Germain; Maissa, Philippe; Mathis, Christian; Coullet, Pierre [Universite de Nice-Sophia Antipolis, Laboratoire J-A Dieudonne, UMR CNRS-UNS 6621, Parc Valrose, 06108 Nice Cedex 02 (France); Philbin, Thomas G; Leonhardt, Ulf, E-mail: Germain.Rousseaux@unice.f [School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews KY16 9SS (United Kingdom)

2010-09-15

Surface waves on a stationary flow of water are considered in a linear model that includes the surface tension of the fluid. The resulting gravity-capillary waves experience a rich array of horizon effects when propagating against the flow. In some cases, three horizons (points where the group velocity of the wave reverses) exist for waves with a single laboratory frequency. Some of these effects are familiar in fluid mechanics under the name of wave blocking, but other aspects, in particular waves with negative co-moving frequency and the Hawking effect, were overlooked until surface waves were investigated as examples of analogue gravity (Schuetzhold R and Unruh W G 2002 Phys. Rev. D 66 044019). A comprehensive presentation of the various horizon effects for gravity-capillary waves is given, with emphasis on the deep water/ short wavelength case kh>>1, where many analytical results can be derived. A similarity of the state space of the waves to that of a thermodynamic system is pointed out.

Quantum black holes: the event horizon as a fuzzy sphere

International Nuclear Information System (INIS)

Dolan, Brian P.

2005-01-01

Modeling the event horizon of a black hole by a fuzzy sphere leads us to modify some suggestions in the literature concerning black hole mass spectra. We derive a formula for the mass spectrum of quantum black holes in terms of four integers which define the area, angular momentum, electric and magnetic charge of the black hole. Although the event horizon becomes a commutative sphere in the classical limit a vestige of the quantum theory still persists in that the event horizon stereographically projects onto the non-commutative plane. We also suggest how the classical bounds on extremal black holes might be modified in the quantum theory. (author)

Apparent violation of the principle of equivalence and Killing horizons

International Nuclear Information System (INIS)

Zimmerman, R.L.; Farhoosh, H.; Oregon Univ., Eugene

1980-01-01

By means of the principle of equivalence it is deduced that the qualitative behavior of the Schwarzschild horizon about a uniformly accelerating particle. This result is confirmed for an exact solution of a uniformly accelerating object in the limit of small accelerations. For large accelerations the Schwarzschild horizon appears to violate the qualitative behavior established via the principle of equivalence. When similar arguments are extended to an observable such as the red shift between two observers, there is no departure from the results expected from the principle of equivalence. The resolution of the paradox is brought about by a compensating effect due to the Rindler horizon. (author)

Subjectivity and Cultural Adjustment in Mathematics Education: A Response to Wolff-Michael Roth

Science.gov (United States)

Brown, Tony

2012-01-01

In this volume, Wolff-Michael Roth provides a critical but partial reading of Tony Brown's book "Mathematics Education and Subjectivity". The reading contrasts Brown's approach with Roth's own conception of subjectivity as derived from the work of Vygotsky, in which Roth aims to "reunite" psychology and sociology. Brown's book, however, focuses on…

What Work Do the Concepts of "Language" and "Literature" Do for Michael Rosenak?

Science.gov (United States)

Levisohn, Jon A.

2014-01-01

Michael Rosenak uses the twin metaphors of "language" and "literature," borrowed from Oakeshott and Peters, to argue that the goal of education is initiation into a language. This goal transcends the study of literature in that language. It includes, as well, the development of the capacity both to critique literature and to…

Start of new Research and Innovation Programme, Horizon 2020

CERN Multimedia

2013-01-01

The overall EU budget for 2014-2020 was approved on 20 November, with €79 billion allocated for the Horizon 2020 Research and Innovation programme.   The first calls and final work programmes in Horizon 2020 will be published on 11 December 2013 and the programme will officially start on 1 January 2014. In preparation for the next major programme, the CERN EU Projects Office has launched a redesigned website to keep you informed and to alert you to opportunities in Horizon 2020: cerneu.web.cern.ch. Organised by Euresearch, the Swiss launch event will take place from 14 to 17 January 2014. This four-day conference will offer the possibility to discover the new European Framework Programme for Research and Innovation. The event is open for registration: www.launch-h2020.ch.

Horizons of cosmology

CERN Document Server

Silk, Joseph

2011-01-01

Horizons of Cosmology: Exploring Worlds Seen and Unseen is the fourth title published in the Templeton Science and Religion Series, in which scientists from a wide range of fields distill their experience and knowledge into brief tours of their respective specialties. In this volume, highly esteemed astrophysicist Joseph Silk explores the vast mysteries and speculations of the field of cosmology in a way that balances an accessible style for the general reader and enough technical detail for advanced students and professionals. Indeed, while the p

How the change in horizon area drives black hole evaporation

International Nuclear Information System (INIS)

Massar, S.; Parentani, R.

2000-01-01

We rephrase the derivation of black hole radiation so as to take into account, at the level of transition amplitudes, the change of the geometry induced by the emission process. This enlarged description reveals that the dynamical variables which govern the emission are the horizon area and its conjugate time variable. Their conjugation is established through the boundary term at the horizon which must be added to the canonical action of general relativity in order to obtain a well defined action principle when the area varies. These coordinates have already been used by Teitelboim and collaborators to compute the partition function of a black hole. We use them to show that the probability to emit a particle is given by e -ΔA/4 , where ΔA is the decrease in horizon area induced by the emission. This expression improves Hawking result which is governed by a temperature (given by the surface gravity) in that the specific heat of the black hole is no longer neglected. The present derivation of quantum black hole radiation is based on the same principles which are used to derive the first law of classical black hole thermodynamics. Moreover, it also applies to quantum processes associated with cosmological or acceleration horizons. These two results indicate that not only black holes but all event horizons possess an entropy which governs processes according to quantum statistical thermodynamics

How to write a competitive proposal for Horizon 2020 a research manager's handbook

CERN Document Server

McCarthy, Sean

2013-01-01

Chapter 1: An Overview of Horizon 2020 ; Chapter 2: How the Research Priorities were Selected (How to Lobby) ; Chapter 3: The Research Priorities in Horizon 2020 ; Chapter 4: How Proposals are Evaluated ; Chapter 5: How to Write the ‘Impact’ of the project ; Chapter 6: The One Page Proposal ; Chapter 7: How to Streamline Proposal Writing ; Chapter 8: How to Find the Best Partners ; Chapter 9: How to Write the ‘Implementation' of the project ; Chapter 10: Legal and Financial Rules in Horizon 2020 ; Chapter 11: What is your Strategy for Horizon 2020?

Briti ekspert : euroliidus kaob Eestist tööpuudus / Michael Richardson ; interv. Airi Ilisson

Index Scriptorium Estoniae

Richardson, Michael

2003-01-01

Eestis Suurbritannia tööreformi tutvustava töö- ja sotsiaalnõuniku sõnul on Suurbritannias peaaegu kadunud pikaajaline töötus noorte hulgas, vanematest inimestest on vaid üksikud tööta kauem kui aasta. Vt. samas: Kes on Michael Richardson?

New Horizons in Education, 2000.

Science.gov (United States)

Ho, Kwok Keung, Ed.

2000-01-01

This document contains the May and November 2000 issues of "New Horizons in Education," with articles in English and Chinese. The May issue includes the following articles: "A Key to Successful Environmental Education: Teacher Trainees' Attitude, Behaviour, and Knowledge" (Kevin Chung Wai Lui, Eric Po Keung Tsang, Sing Lai…

Gravitational lensing and ghost images in the regular Bardeen no-horizon spacetimes

International Nuclear Information System (INIS)

Schee, Jan; Stuchlík, Zdeněk

2015-01-01

We study deflection of light rays and gravitational lensing in the regular Bardeen no-horizon spacetimes. Flatness of these spacetimes in the central region implies existence of interesting optical effects related to photons crossing the gravitational field of the no-horizon spacetimes with low impact parameters. These effects occur due to existence of a critical impact parameter giving maximal deflection of light rays in the Bardeen no-horizon spacetimes. We give the critical impact parameter in dependence on the specific charge of the spacetimes, and discuss 'ghost' direct and indirect images of Keplerian discs, generated by photons with low impact parameters. The ghost direct images can occur only for large inclination angles of distant observers, while ghost indirect images can occur also for small inclination angles. We determine the range of the frequency shift of photons generating the ghost images and determine distribution of the frequency shift across these images. We compare them to those of the standard direct images of the Keplerian discs. The difference of the ranges of the frequency shift on the ghost and direct images could serve as a quantitative measure of the Bardeen no-horizon spacetimes. The regions of the Keplerian discs giving the ghost images are determined in dependence on the specific charge of the no-horizon spacetimes. For comparison we construct direct and indirect (ordinary and ghost) images of Keplerian discs around Reissner-Nördström naked singularities demonstrating a clear qualitative difference to the ghost direct images in the regular Bardeen no-horizon spacetimes. The optical effects related to the low impact parameter photons thus give clear signature of the regular Bardeen no-horizon spacetimes, as no similar phenomena could occur in the black hole or naked singularity spacetimes. Similar direct ghost images have to occur in any regular no-horizon spacetimes having nearly flat central region

Output-feedback control of combined sewer networks through receding horizon control with moving horizon estimation

Science.gov (United States)

Joseph-Duran, Bernat; Ocampo-Martinez, Carlos; Cembrano, Gabriela

2015-10-01

An output-feedback control strategy for pollution mitigation in combined sewer networks is presented. The proposed strategy provides means to apply model-based predictive control to large-scale sewer networks, in-spite of the lack of measurements at most of the network sewers. In previous works, the authors presented a hybrid linear control-oriented model for sewer networks together with the formulation of Optimal Control Problems (OCP) and State Estimation Problems (SEP). By iteratively solving these problems, preliminary Receding Horizon Control with Moving Horizon Estimation (RHC/MHE) results, based on flow measurements, were also obtained. In this work, the RHC/MHE algorithm has been extended to take into account both flow and water level measurements and the resulting control loop has been extensively simulated to assess the system performance according different measurement availability scenarios and rain events. All simulations have been carried out using a detailed physically based model of a real case-study network as virtual reality.

Flying by Ear: Blind Flight with a Music-Based Artificial Horizon

Science.gov (United States)

Simpson, Brian D.; Brungart, Douglas S.; Dallman, Ronald C.; Yasky, Richard J., Jr.; Romigh, Griffin

2008-01-01

Two experiments were conducted in actual flight operations to evaluate an audio artificial horizon display that imposed aircraft attitude information on pilot-selected music. The first experiment examined a pilot's ability to identify, with vision obscured, a change in aircraft roll or pitch, with and without the audio artificial horizon display. The results suggest that the audio horizon display improves the accuracy of attitude identification overall, but differentially affects response time across conditions. In the second experiment, subject pilots performed recoveries from displaced aircraft attitudes using either standard visual instruments, or, with vision obscured, the audio artificial horizon display. The results suggest that subjects were able to maneuver the aircraft to within its safety envelope. Overall, pilots were able to benefit from the display, suggesting that such a display could help to improve overall safety in general aviation.

Outside in America: George Michael's music video, public sex and global pop culture

NARCIS (Netherlands)

Kooijman, J.

2004-01-01

Six months after his controversial arrest for ‘lewd conduct’ at a men’s public restroom in Beverly Hills, British pop star George Michael released the song and music video ‘Outside’ which can be seen as an explicit commentary on the controversy. In this article, I read the music video in three ways:

Black Hole Horizons and Thermodynamics: A Quantum Approach

Directory of Open Access Journals (Sweden)

Nicola Pinamonti

2010-07-01

Full Text Available We focus on quantization of the metric of a black hole restricted to the Killing horizon with universal radius r0. After imposing spherical symmetry and after restriction to the Killing horizon, the metric is quantized employing the chiral currents formalism. Two "components of the metric" are indeed quantized: The former behaves as an affine scalar field under changes of coordinates, the latter is instead a proper scalar field. The action of the symplectic group on both fields is realized in terms of certain horizon diffeomorphisms. Depending on the choice of the vacuum state, such a representation is unitary. If the reference state of the scalar field is a coherent state rather than a vacuum, spontaneous breaking of conformal symmetry arises and the state contains a Bose-Einstein condensate. In this case the order parameter fixes the actual size of the black hole with respect to r0. Both the constructed state together with the one associated with the affine scalar are thermal states (KMS with respect to Schwarzschild Killing time when restricted to half horizon. The value of the order parameter fixes the temperature at the Hawking value as well. As a result, it is found that the quantum energy and entropy densities coincide with the black hole mass and entropy, provided the universal parameter r0 is suitably chosen, not depending on the size of the actual black hole in particular.

[The problem of evil in families--the filmmaker Michael Haneke].

Science.gov (United States)

Skårderud, Finn

2010-09-23

With the beautiful and dark film "The white ribbon", from 2009, the Austrian film director Michael Haneke consolidated his status as an international success. A central theme in his films is evilness and its roots. But just as important is his ambition to develop films where evil is not only portrayed, but where spectators are challenged to relate to their own ethical standards and their role as spectators. Haneke is a highly original filmmaker with his consistent search for a film aesthetic that stimulates ethical self-reflection and mentalizing. He partly succeeds in this quest.

Adapting Shakespeare – Converting Shylock in Michael Radford’s the Merchant of Venice

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Oakes Luke

2016-08-01

Full Text Available This article aims to explore the extension and evolution of Shakespeare’s The Merchant of Venice through Michael Radford’s 2004 cinematic adaptation. By investigating the concept of adaptation and the significance of intertextuality, Shakespeare’s source text is considered alongside Radford’s twenty-first century recreation to reimagine and redefine the construction of Shylock as both a comic and tragic device utilized across film and play. Issues of racial and religious prejudices alongside anti- Semitic views were particularly prominent in Elizabethan England and, by concentrating on recontextualisation, this article looks to expose Shakespeare’s characterization as a reflective commentary concerning societal discriminations at the time of the play’s performance. By focusing primarily on Shakespeare’s Jewish Usurer, Radford is able to reconstruct and reestablish the dramatic devices and characters within the cinematic version, metaphorically converting Shylock from comic villain to tragic victim. Finally, it argues that this dynamic shift inevitably metamorphoses Shylock from a spectator’s perspective and provides Michael Radford with an opportunity to offer a social commentary on social inequality in the twenty-first century.

Priority Questions and Horizon Scanning for Conservation: A Comparative Study

Science.gov (United States)

Kark, Salit; Sutherland, William J.; Shanas, Uri; Klass, Keren; Achisar, Hila; Dayan, Tamar; Gavrieli, Yael; Justo-Hanani, Ronit; Mandelik, Yael; Orion, Nir; Pargament, David; Portman, Michelle; Reisman-Berman, Orna; Safriel, Uriel N.; Schaffer, Gad; Steiner, Noa; Tauber, Israel; Levin, Noam

2016-01-01

Several projects aimed at identifying priority issues for conservation with high relevance to policy have recently been completed in several countries. Two major types of projects have been undertaken, aimed at identifying (i) policy-relevant questions most imperative to conservation and (ii) horizon scanning topics, defined as emerging issues that are expected to have substantial implications for biodiversity conservation and policy in the future. Here, we provide the first overview of the outcomes of biodiversity and conservation-oriented projects recently completed around the world using this framework. We also include the results of the first questions and horizon scanning project completed for a Mediterranean country. Overall, the outcomes of the different projects undertaken (at the global scale, in the UK, US, Canada, Switzerland and in Israel) were strongly correlated in terms of the proportion of questions and/or horizon scanning topics selected when comparing different topic areas. However, some major differences were found across regions. There was large variation among regions in the percentage of proactive (i.e. action and response oriented) versus descriptive (non-response oriented) priority questions and in the emphasis given to socio-political issues. Substantial differences were also found when comparing outcomes of priority questions versus horizon scanning projects undertaken for the same region. For example, issues related to climate change, human demography and marine ecosystems received higher priority as horizon scanning topics, while ecosystem services were more emphasized as current priority questions. We suggest that future initiatives aimed at identifying priority conservation questions and horizon scanning topics should allow simultaneous identification of both current and future priority issues, as presented here for the first time. We propose that further emphasis on social-political issues should be explicitly integrated into future

Training and Mastery of Techniques in Wittgenstein's Later Philosophy: A Response to Michael Luntley

Science.gov (United States)

Stickney, Jeff

2008-01-01

Responding to Michael Luntley's article, "Learning, Empowerment and Judgement," the author shows he cannot successfully make the following three moves: (1) dissolve the analytic distinction between learning by training and learning by reasoning, while advocating the latter; (2) diminish the role of training in Wittgenstein's philosophy, nor…

European Management: an emerging competitive advantage of European nations : A reply to Michael Porter

NARCIS (Netherlands)

F.A.J. van den Bosch (Frans); A.A. van Prooijen

1992-01-01

textabstractThis article extends the debate begun in the June 1992 issue of EMJ when the authors first criticized Michael Porter's explanatory framework in his Competitive Advantage of Nations (1990), over the role of national culture on the competitive advantage of nations. In this paper, Frans van

Stochastic Dynamics of Clay Translocation and Formation of Argillic Horizons

Science.gov (United States)

Calabrese, S.; Richter, D. D., Jr.; Porporato, A. M.

2017-12-01

The formation of argillic horizons in vertical soil profiles is mainly attributed to lessivage, namely the transport of clay from an upper E horizon to a deeper illuviated horizon. Because of the long timescales involved in this phenomenon, quantitative modeling is useful to explore the role of clay lessivage on soil formation and sub-surface clay accumulation. The limitations of detailed models of colloidal transport to short timescales make it necessary to resort to simple models. Here, we present a parsimonious model of clay transport in which lessivage is interpreted stochastically. Clay particles approach the soil surface at a speed equal to the erosion rate and are intermittently transported to deeper soil layers when percolation events occur or removed by erosion. Along with the evolution of clay particles trajectories, the model predicts the vertical clay profile, the depth of the B horizon, and the mean time to erosion. Dimensional analysis reveals the two dimensionless parameters governing the dynamics, leading to a new classification of soil types based on erosion rates and intensity of lessivage.

The role of event horizons in quantum gravity

International Nuclear Information System (INIS)

Schiffer, M.

1990-01-01

We extend Bekenstein's result for the minimum variation of the black hole event horizon due to the absorption of an extended (classical) particle to the deSitter Universe. These classical equations are the bulk for the argument based on correspondence principle: for large energies the classical and quantum results are in correspondence with each other. The outcome of this reasoning could not be more fruitful: it leads to the quantization of the event horizon area (either B.H. or cosmological) in units of Planck's length square. Consequence are discussed. (author)

Horizon geometry for Kerr black holes with synchronized hair

Science.gov (United States)

Delgado, Jorge F. M.; Herdeiro, Carlos A. R.; Radu, Eugen

2018-06-01

We study the horizon geometry of Kerr black holes (BHs) with scalar synchronized hair [1], a family of solutions of the Einstein-Klein-Gordon system that continuously connects to vacuum Kerr BHs. We identify the region in parameter space wherein a global isometric embedding in Euclidean 3-space, E3, is possible for the horizon geometry of the hairy BHs. For the Kerr case, such embedding is possible iff the horizon dimensionless spin jH (which equals the total dimensionless spin, j ), the sphericity s and the horizon linear velocity vH are smaller than critical values, j(S ),s(S ),vH(S ), respectively. For the hairy BHs, we find that jH

New view about black holes. [Tachyon--bradyon transformation at horizon

Energy Technology Data Exchange (ETDEWEB)

De Sabbata, V; Pavsic, M; Recami, E

1977-01-01

For a Schwarzschild black-hole, as reference frame is chosen the frame sigma at rest with respect to the Schwarzschild metric. In this locally non-inertial frame, a freely falling body is shown to reach the speed of light on the horizon and then to travel faster than light inside the horizon. The usual Szekeres--Kruskal (SK) coordinates represent themselves frames that (with respect to the frames sigma) travel at subluminal speed outside, at luminal speed on, and at superluminal speed inside the horizon (so that SK frames always describe any free falling body as a standard, slower-than-light object). Finally, black-holes are shown to be possible sources of tachyons.

Las relaciones entre la Iglesia y el Estado en la teoría de la justicia de Michael Walzer

OpenAIRE

Roldán, Alberto Fernando

2009-01-01

Roldan, A. F. (2009). Las relaciones entre la Iglesia y el Estado en la teoría de la justicia de Michael Walzer (Tesis de Maestría). Universidad Nacional de Quilmes, Bernal, Argentina. En la presente tesis, se discuten las relaciones entre la Iglesia –término que se utiliza no en el sentido confesional sino en tanto institución religiosa- y el Estado moderno. Se escoge como marco teórico la filosofía política del pensador judío americano Michael Walzer, exponente del “comunitarismo”, un...

Coordinated control of micro-grid based on distributed moving horizon control.

Science.gov (United States)

Ma, Miaomiao; Shao, Liyang; Liu, Xiangjie

2018-05-01

This paper proposed the distributed moving horizon coordinated control scheme for the power balance and economic dispatch problems of micro-grid based on distributed generation. We design the power coordinated controller for each subsystem via moving horizon control by minimizing a suitable objective function. The objective function of distributed moving horizon coordinated controller is chosen based on the principle that wind power subsystem has the priority to generate electricity while photovoltaic power generation coordinates with wind power subsystem and the battery is only activated to meet the load demand when necessary. The simulation results illustrate that the proposed distributed moving horizon coordinated controller can allocate the output power of two generation subsystems reasonably under varying environment conditions, which not only can satisfy the load demand but also limit excessive fluctuations of output power to protect the power generation equipment. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Behaviour of scalar perturbations of a Reissner-Nordstroem black hole inside the event horizon

International Nuclear Information System (INIS)

McNamara, J.M.

1978-01-01

This paper considers general scalar perturbations of a Reissner-Nordstrom black hole and examines the qualitative behaviour of these perturbations in the region between and on the inner and outer horizons. Initial data are specified in terms of the ingoing radiation crossing the outer (event) horizon. The only essential restriction on these data is that the radiation should not die away too slowly on this horizon. The resultant perturbations are shown to be bounded and continuous. In particular, these properties hold for perturbations on the inner horizon. For certain types of scalar field (including the zero rest mass scalar field) perturbations vanish at the cross-over point on the inner horizon. (author)

Near-Horizon Geodesics for Astrophysical and Idealised Black Holes: Coordinate Velocity and Coordinate Acceleration

Directory of Open Access Journals (Sweden)

Petarpa Boonserm

2018-05-01

Full Text Available Geodesics (by definition have an intrinsic 4-acceleration zero. However, when expressed in terms of coordinates, the coordinate acceleration d 2 x i / d t 2 can very easily be non-zero, and the coordinate velocity d x i / d t can behave unexpectedly. The situation becomes extremely delicate in the near-horizon limit—for both astrophysical and idealised black holes—where an inappropriate choice of coordinates can quite easily lead to significant confusion. We shall carefully explore the relative merits of horizon-penetrating versus horizon-non-penetrating coordinates, arguing that in the near-horizon limit the coordinate acceleration d 2 x i / d t 2 is best interpreted in terms of horizon-penetrating coordinates.

The Educational Philosophies of Mordecai Kaplan and Michael Rosenak: Surprising Similarities and Illuminating Differences

Science.gov (United States)

Schein, Jeffrey; Caplan, Eric

2014-01-01

The thoughts of Mordecai Kaplan and Michael Rosenak present surprising commonalities as well as illuminating differences. Similarities include the perception that Judaism and Jewish education are in crisis, the belief that Jewish peoplehood must include commitment to meaningful content, the need for teachers to teach from a position of…

« To see beyond the horizon of mere selfishness » : l’horizon moral dans les romans de George Eliot

OpenAIRE

Toussaint, Benjamine

2015-01-01

In spite of her apostasy, George Eliot still believed in the moral and spiritual values of Christianity and it is hardly surprising she should have used the metaphor of the horizon to refer to this ideal notion of the essence of Christianity since the horizon is both unreachable and yet always visible, showing the direction one ought to follow. Her characters’ moral odyssey is about learning to see beyond the limits of their own self-centered experience; however, as Lydgate underlines in Midd...

Obituary: Michael John Klein, 1940-2005

Science.gov (United States)

Gulkis, Samuel

2006-12-01

Michael John Klein died on 14 May 2005 at home in South Pasadena, California. The cause of death was tongue cancer that metastasized to the lungs. He was a non-smoker. Mike was a passionate radio astronomer, a trusted astronomical observer, an educator and a family man. Mike was born on 19 January 1940 in Ames, Iowa, the son of Florence Marie (Graf) and Fred Michael Klein. His mother was a homemaker, and his father was a banker. Mike had two older sisters, Lois Jean (Klein) Flauher and Marilyn June (Klein) Griffin. In 1962, Mike married his high school sweetheart Barbara Dahlberg, who survives him along with their three children, Kristin Marie (Klein) Shields, Michael John Klein Jr., Timothy Joel Klein, and six grandchildren. Mike developed a love for astronomy early in his life, and credited an early morning, newspaper-delivery route that he had at age twelve, which took him outside well before sunrise. He told family members that as he walked along his route, he stared into the sky and wondered what everything was. He studied sky charts, located stars, and began to understand how the planets shifted their positions relative to the stars each day. Another big influence in Mike's life was his brother in-law, Jim Griffin. Jim helped Mike understand that his passion for science did not have to remain a hobby, but could and should become a career. Jim's encouragement led Mike to attend Iowa State University in Ames, where he earned a BS in electrical engineering in 1962. Mike then started graduate school in electrical engineering at Michigan State, but after one semester transferred to the University of Michigan, Ann Arbor, where he earned an MS (1966) and PhD (1968) in astronomy. His doctoral dissertation, under the direction of Professor Fred Haddock, was based on extensive observations of the planets and examined the physical and thermal properties of planetary atmospheres and surfaces. Mike was awarded a Resident Research Associate position at JPL by the National

Unified first law and the thermodynamics of the apparent horizon in the FRW universe

International Nuclear Information System (INIS)

Cai Ronggen; Cao Liming

2007-01-01

In this paper we revisit the relation between the Friedmann equations and the first law of thermodynamics. We find that the unified first law first proposed by Hayward to treat the outertrapping horizon of a dynamical black hole can be used to the apparent horizon (a kind of inner trapping horizon in the context of the FRW cosmology) of the FRW universe. We discuss three kinds of gravity theorties: Einstein theory, Lovelock thoery, and scalar-tensor theory. In Einstein theory, the first law of thermodynamics is always satisfied on the apparent horizon. In Lovelock theory, treating the higher derivative terms as an effective energy-momentum tensor, we find that this method can give the same entropy formula for the apparent horizon as that of black hole horizon. This implies that the Clausius relation holds for the Lovelock theory. In scalar-tensor gravity, we find, by using the same procedure, the Clausius relation no longer holds. This indicates that the apparent horizon of the FRW universe in the scalar-tensor gravity corresponds to a system of nonequilibrium thermodynamics. We show this point by using the method developed recently by Eling et al. for dealing with the f(R) gravity

Topology and geometry of six-dimensional (1, 0) supergravity black hole horizons

International Nuclear Information System (INIS)

Akyol, M; Papadopoulos, G

2012-01-01

We show that the supersymmetric near horizon black hole geometries of six-dimensional supergravity coupled to any number of scalar and tensor multiplets are either locally AdS 3 x Σ 3 , where Σ 3 is a homology 3-sphere, or R 1,1 )xS 4 , where S 4 is a 4-manifold whose geometry depends on the hypermultiplet scalars. In both cases, we find that the tensorini multiplet scalars are constant and the associated 3-form field strengths vanish. We also demonstrate that the AdS 3 x Σ 3 horizons preserve two, four and eight supersymmetries. For horizons with four supersymmetries, Σ 3 is in addition a non-trivial circle fibration over a topological 2-sphere. The near horizon geometries preserving eight supersymmetries are locally isometric to either AdS 3 x S 3 or R 1, 1 x T 4 . Moreover, we show that the R 1,1 xS horizons preserve one, two and four supersymmetries and the geometry of S is Riemann, Kaehler and hyper-Kaehler, respectively. (paper)

Horizon Wavefunction of Generalized Uncertainty Principle Black Holes

Directory of Open Access Journals (Sweden)

Luciano Manfredi

2016-01-01

Full Text Available We study the Horizon Wavefunction (HWF description of a Generalized Uncertainty Principle inspired metric that admits sub-Planckian black holes, where the black hole mass m is replaced by M=m1+β/2MPl2/m2. Considering the case of a wave-packet shaped by a Gaussian distribution, we compute the HWF and the probability PBH that the source is a (quantum black hole, that is, that it lies within its horizon radius. The case β0, where a minimum in PBH is encountered, thus meaning that every particle has some probability of decaying to a black hole. Furthermore, for sufficiently large β we find that every particle is a quantum black hole, in agreement with the intuitive effect of increasing β, which creates larger M and RH terms. This is likely due to a “dimensional reduction” feature of the model, where the black hole characteristics for sub-Planckian black holes mimic those in (1+1 dimensions and the horizon size grows as RH~M-1.

How Do Large Companies Manage Their Investments Across the Three Horizons?

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Peter Carbone

2012-04-01

Full Text Available Technical entrepreneurship continues to be important to a technology company’s health and growth, even after it has successfully delivered its first product. It is essential to help the company deal with competitive forces and to renew its revenue stream. However, as the company grows, its entrepreneurial capability often becomes handicapped both by company culture as well as external pressures. The company must achieve the right mix of investment and level of attention across three time horizons of growth: immediate, imminent, and future. This balancing act requires a commitment to a strategic growth goal, appropriate tools, and leaders that can manage significant degrees of uniqueness in the resources that address each of these time horizons. This article discusses some of the horizon-management challenges faced by top management teams of large companies and overviews some mechanisms and processes that have worked effectively. Large companies must overcome internal teams’ divergent values and culture as well as significant external, short-term pressures being applied by their existing base of customers and markets. Discipline at the entry point to Horizon 3 (exploratory phase and then a rapid transition to Horizon 1 (current operations is the priority of any successful growth company.

TIME HORIZON AND UNCOVERED INTEREST PARITY IN EMERGING ECONOMIES

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Norlida Hanim Mohd Salleh

2011-07-01

Full Text Available The aim of this study is to re-examine the well-known empirical puzzle of uncovered interest parity (UIP for emerging market economies with different prediction time horizons. The empirical results obtained using dynamic panel and time series techniques for monthly data from January 1995 to December 2009 eventually show that the panel data estimates are more powerful than those obtained by applying individual time series estimations and the significant contribution of the exchange rate prediction horizons in determining the status of UIP. This finding reveals that at the longer time horizon, the model has better econometric specification and thus more predictive power for exchange rate movements compared to the shorter time period. The findings can also be a signalling of well-integrated currency markets and a reliable guide to international investors as well as for the orderly conduct of monetary authorities.

On the near horizon rotating black hole geometries with NUT charges

Energy Technology Data Exchange (ETDEWEB)

Galajinsky, Anton; Orekhov, Kirill [Tomsk Polytechnic University, Laboratory of Mathematical Physics, Tomsk (Russian Federation)

2016-09-15

The near horizon geometries are usually constructed by implementing a specific limit to a given extreme black hole configuration. Their salient feature is that the isometry group includes the conformal subgroup SO(2, 1). In this work, we turn the logic around and use the conformal invariants for constructing Ricci-flat metrics in d = 4 and d = 5 where the vacuum Einstein equations reduce to a coupled set of ordinary differential equations. In four dimensions the analysis can be carried out in full generality and the resulting metric describes the d = 4 near horizon Kerr-NUT black hole. In five dimensions we choose a specific ansatz whose structure is similar to the d = 5 near horizon Myers-Perry black hole. A Ricci-flat metric involving five arbitrary parameters is constructed. A particular member of this family, which is characterized by three parameters, seems to be a natural candidate to describe the d = 5 near horizon Myers- Perry black hole with a NUT charge. (orig.)

On the near horizon rotating black hole geometries with NUT charges

International Nuclear Information System (INIS)

Galajinsky, Anton; Orekhov, Kirill

2016-01-01

The near horizon geometries are usually constructed by implementing a specific limit to a given extreme black hole configuration. Their salient feature is that the isometry group includes the conformal subgroup SO(2, 1). In this work, we turn the logic around and use the conformal invariants for constructing Ricci-flat metrics in d = 4 and d = 5 where the vacuum Einstein equations reduce to a coupled set of ordinary differential equations. In four dimensions the analysis can be carried out in full generality and the resulting metric describes the d = 4 near horizon Kerr-NUT black hole. In five dimensions we choose a specific ansatz whose structure is similar to the d = 5 near horizon Myers-Perry black hole. A Ricci-flat metric involving five arbitrary parameters is constructed. A particular member of this family, which is characterized by three parameters, seems to be a natural candidate to describe the d = 5 near horizon Myers- Perry black hole with a NUT charge. (orig.)

Evaluating information in multiple horizon forecasts. The DOE's energy price forecasts

International Nuclear Information System (INIS)

Sanders, Dwight R.; Manfredo, Mark R.; Boris, Keith

2009-01-01

The United States Department of Energy's (DOE) quarterly price forecasts for energy commodities are examined to determine the incremental information provided at the one-through four-quarter forecast horizons. A direct test for determining information content at alternative forecast horizons, developed by Vuchelen and Gutierrez [Vuchelen, J. and Gutierrez, M.-I. 'A Direct Test of the Information Content of the OECD Growth Forecasts.' International Journal of Forecasting. 21(2005):103-117.], is used. The results suggest that the DOE's price forecasts for crude oil, gasoline, and diesel fuel do indeed provide incremental information out to three-quarters ahead, while natural gas and electricity forecasts are informative out to the four-quarter horizon. In contrast, the DOE's coal price forecasts at two-, three-, and four-quarters ahead provide no incremental information beyond that provided for the one-quarter horizon. Recommendations of how to use these results for making forecast adjustments is also provided. (author)

Wolff-Michael Roth's passibility: at the limits of the constructivist metaphor: a book review

Science.gov (United States)

Brendel, Michelle

2014-12-01

Wolff-Michael Roth deconstructs the preeminent role conceded to constructivism in Science Education and demonstrates how we learn and know through pain, suffering, love or passion. This review explores his book "Passibility: At the Limits of the Constructivist Metaphor" through the eyes of an outsider to the world of science education.

"Raising Standards" or Reducing Aspirations and Opportunities Still Further? Michael Gove and Examination Reforms

Science.gov (United States)

Allen, Martin

2013-01-01

Well before the examinations grade crisis of 2012, Michael Gove had set out clear intentions for reforming public examinations. Though he claimed to be improving examinations and assessment by replicating practices that took place in high-performing countries and thus improving the ability of the UK economy to "compete", this…

O que é a Multidão? Questões para Michael Hardt e Antonio Negri

Directory of Open Access Journals (Sweden)

Nicholas Brown

2006-07-01

Full Text Available Multidão, livro mais recente de Michael Hardt e Antonio Negri, é uma tentativa de nomear e compreender as condições que envolvem a dinâmica social do século xxi. Na entrevista a seguir, Hardt e Negri discorrem sobre as possibilidades de constituição da multidão como agente político, discutem os fundamentos do livro e defendem conceitos que consideram determinantes para a compreensão dos novos tempos, tais como biopolítica e biopoder.Multitude, Michael Hardt and Antonio Negri’s latest book, is an attempt at understanding conditions involving social dynamics in the xxi century. In the interview below, Hardt and Negri consider the constitution of the multitude as a political agent, discuss the structure of their book and support concepts seen as crucial for the comprehension of our time, such as biopolitics and biopower.

Event horizon and scalar potential

International Nuclear Information System (INIS)

Duruisseau, J.P.; Tonnelat, M.A.

1977-01-01

The introduction of a scalar potential with a more general scheme than General Relativity eliminates the event horizon. Among possible solutions, the Schwarzschild one represents a singular case. A study of the geodesic properties of the matching with an approximated interior solution are given. A new definition of the gravitational mass and chi function is deduced. (author)

Expanding Your Horizons Conference in Geneva

CERN Multimedia

Chromek-Burckhart, Doris

2011-01-01

CERN and its experiments participated in Expanding Your Horizons (EYH) in Science and Mathematics conference in Geneva on 12th November. EYH nurture girls' interest in science and math courses to encourage them to consider careers in science, technology, engineering, and math.

Correction: Synthesis of pyrrolidine-3-carboxylic acid derivatives via asymmetric Michael addition reactions of carboxylate-substituted enones.

Science.gov (United States)

Yin, Feng; Garifullina, Ainash; Tanaka, Fujie

2018-04-25

Correction for 'Synthesis of pyrrolidine-3-carboxylic acid derivatives via asymmetric Michael addition reactions of carboxylate-substituted enones' by Feng Yin et al., Org. Biomol. Chem., 2017, 15, 6089-6092.

Modeling of the development of humus horizons in soils of Crimea

Science.gov (United States)

Ergina, E. I.

2017-01-01

Current approaches to the simulation of pedogenesis processes in time are considered. Models for the formation of humus horizon on parent rocks of different genesis in Crimea are presented. Formation rates of humus horizons have been determined, which allows developing the remediation strategies for mining dumps of mineral deposits in Crimea.

Aligned electromagnetic excitations of a black hole and their impact on its quantum horizon

Energy Technology Data Exchange (ETDEWEB)

Burinskii, Alexander [Gravity Research Group, NSI, Russian Academy of Sciences, B. Tulskaya 52, Moscow 115191 (Russian Federation)], E-mail: bur@ibrae.ac.ru; Elizalde, Emilio [Instituto de Ciencias del Espacio (CSIC) and Institut d' Estudis Espacials de Catalunya (IEEC/CSIC), Campus UAB, Facultat de Ciencies, Torre C5-Parell-2a planta, 08193 Bellaterra, Barcelona (Spain)], E-mail: elizalde@ieec.uab.es; Hildebrandt, Sergi R. [Instituto de Astrofisica de Canarias, C/Via Lactea s/n, La Laguna, Tenerife 38200 (Spain)], E-mail: srh@iac.es; Magli, Giulio [Dipartimento di Matematica del Politecnico di Milano, Piazza Leonardo Da Vinci 32, 20133 Milano (Italy)], E-mail: magli@mate.polimi.it

2009-02-02

We show that elementary aligned electromagnetic excitations of black holes, as coming from exact Kerr-Schild solutions, represent light-like beams pulses which have a very strong back reaction on the metric and change the topology of the horizon. Based on York's proposal, that elementary deformations of the BH horizon are related with elementary vacuum fluctuations, we analyze deformations of the horizon caused by the beam-like vacuum fluctuations and obtain a very specific feature of the topological deformations of the horizon. In particular, we show how the beams pierce the horizon, forming a multitude of micro-holes in it. A conjecture is taken into consideration, that these specific excitations are connected with the conformal-analytic properties of the Kerr geometry and are at the base of the emission mechanism.

Horizons and non-local time evolution of quantum mechanical systems

International Nuclear Information System (INIS)

Casadio, Roberto

2015-01-01

According to general relativity, trapping surfaces and horizons are classical causal structures that arise in systems with sharply defined energy and corresponding gravitational radius. The latter concept can be extended to a quantum mechanical matter state simply by means of the spectral decomposition, which allows one to define an associated ''horizon wave-function''. Since this auxiliary wave-function contains crucial information about the causal structure of space-time, a new proposal is formulated for the time evolution of quantum systems in order to account for the fundamental classical property that outer observers cannot receive signals from inside a horizon. The simple case of a massive free particle at rest is used throughout the paper as a toy model to illustrate the main ideas. (orig.)

Seeking for toroidal event horizons from initially stationary BH configurations

International Nuclear Information System (INIS)

Ponce, Marcelo; Lousto, Carlos; Zlochower, Yosef

2011-01-01

We construct and evolve non-rotating vacuum initial data with a ring singularity, based on a simple extension of the standard Brill-Lindquist multiple BH initial data, and search for event horizons with spatial slices that are toroidal when the ring radius is sufficiently large. While evolutions of the ring singularity are not numerically feasible for large radii, we find some evidence, based on configurations of multiple BHs arranged in a ring, that this configuration leads to singular limit where the horizon width has zero size, possibly indicating the presence of a naked singularity, when the radius of the ring is sufficiently large. This is in agreement with previous studies that have found that there is no apparent horizon surrounding the ring singularity when the ring's radius is larger than about twice its mass.

Horizons in Matter:. Black Hole Hair Versus Null Big Bang

Science.gov (United States)

Bronnikov, K. A.; Zaslavskii, Oleg B.

It is shown that only particular kinds of matter (in terms of the "radial" pressure-to-density ratio w) can coexist with Killing horizons in black hole or cosmological space-times. Thus, for arbitrary (not necessarily spherically symmetric) static black holes, admissible are vacuum matter (w = -1, i.e. the cosmological constant or its generalization with the same value of w) and matter with certain values of w between 0 and -1, in particular a gas of disordered cosmic strings (w = -1/3). If the cosmological evolution starts from a horizon (the so-called null big bang scenarios), this horizon can coexist with vacuum matter and certain kinds of phantom matter with w ≤ -3. It is concluded that normal matter in such scenarios is entirely created from vacuum.

Agriculture’s Ethical Horizon, book review

Science.gov (United States)

Roughly 6.5 billion people inhabit the earth, but over 1 billion people regularly go hungry. This food shortfall poses an ethical dilemma for agriculture, and Agriculture's Ethical Horizon grapples with this dilemma. It argues that agricultural productivity has been the quintessential value of agr...

Near-Optimal Tracking Control of Mobile Robots Via Receding-Horizon Dual Heuristic Programming.

Science.gov (United States)

Lian, Chuanqiang; Xu, Xin; Chen, Hong; He, Haibo

2016-11-01

Trajectory tracking control of wheeled mobile robots (WMRs) has been an important research topic in control theory and robotics. Although various tracking control methods with stability have been developed for WMRs, it is still difficult to design optimal or near-optimal tracking controller under uncertainties and disturbances. In this paper, a near-optimal tracking control method is presented for WMRs based on receding-horizon dual heuristic programming (RHDHP). In the proposed method, a backstepping kinematic controller is designed to generate desired velocity profiles and the receding horizon strategy is used to decompose the infinite-horizon optimal control problem into a series of finite-horizon optimal control problems. In each horizon, a closed-loop tracking control policy is successively updated using a class of approximate dynamic programming algorithms called finite-horizon dual heuristic programming (DHP). The convergence property of the proposed method is analyzed and it is shown that the tracking control system based on RHDHP is asymptotically stable by using the Lyapunov approach. Simulation results on three tracking control problems demonstrate that the proposed method has improved control performance when compared with conventional model predictive control (MPC) and DHP. It is also illustrated that the proposed method has lower computational burden than conventional MPC, which is very beneficial for real-time tracking control.

Effective first law of thermodynamics of black holes with two horizons

International Nuclear Information System (INIS)

Yi-Huan, Wei

2009-01-01

For a black hole with two horizons, the effective entropy is assumed to be a linear combination of the two entropies of the outer and inner horizons. In terms of the effective thermodynamic quantities the effective Bekenstein–Smarr formula and the effective first law of thermodynamics are derived. (geophysics, astronomy and astrophysics)

Factors influencing organic-horizon carbon pools in mixed-species stands of central Maine, USA

Science.gov (United States)

Joshua J. Puhlick; Shawn Fraver; Ivan J. Fernandez; Aaron R. Weiskittel; Laura S. Kenefic; Randy Kolka; Marie-Cecile Gruselle

2016-01-01

The overall goal of this study was to evaluate the correlation of multiple abiotic and biotic factors with organic-horizon (O-horizon) carbon (C) content on the Penobscot Experimental Forest in central Maine, USA. O-horizon samples were collected and their associated depths were recorded from stands managed with a range of silvicultural and harvesting treatments (i.e...

Cosmological horizons and reconstruction of quantum field theories

International Nuclear Information System (INIS)

Dappiaggi, C.; Pinamonti, N.

2007-12-01

As a starting point for this manuscript, we remark how the cosmological horizon of a certain class of Friedmann-Robertson-Walker backgrounds shares some non trivial geometric properties with null infinity in an asymptotically flat spacetime. Such a feature is generalized to a larger class of expanding spacetimes M admitting a geodesically complete cosmological horizon J - common to all co-moving observers. This property is later exploited in order to recast, in a cosmological background, some recent results for a linear scalar quantum field theory in spacetimes asymptotically flat at null infinity. Under suitable hypotheses on M - valid for de Sitter spacetime and some other FRW spacetimes obtained by perturbing deSitter space - the algebra of observables for a Klein-Gordon field is mapped into a subalgebra of the algebra of observables W(J - ) constructed on the cosmological horizon. There is exactly one pure quasifree state λ on W(J - ) which fulfills a suitable energy positivity condition with respect to a generator related with the cosmological time displacements. Furthermore λ induces a preferred physically meaningful quantum state λ M for the quantum theory in the bulk. If M admits a timelike Killing generator preserving J - , then the associated self-adjoint generator in the GNS representation of λ M has positive spectrum (i.e. energy). Moreover λ M turns out to be invariant under every symmetry of the bulk metric which preserves the cosmological horizon. In the case of an expanding de Sitter spacetime, λ M coincides with the Euclidean (Bunch-Davies) vacuum state, hence being Hadamard in this case. Remarks on the validity of the Hadamard property for λ M in more general spacetimes are presented. (orig.)

Summary and status of the Horizons ephemeris system

Science.gov (United States)

Giorgini, J.

2011-10-01

Since 1996, the Horizons system has provided searchable access to JPL ephemerides for all known solar system bodies, several dozen spacecraft, planetary system barycenters, and some libration points. Responding to 18 400 000 requests from 300 000 unique addresses, the system has recently averaged 420 000 ephemeris requests per month. Horizons is accessed and automated using three interfaces: interactive telnet, web-browser form, and e-mail command-file. Asteroid and comet ephemerides are numerically integrated from JPL's database of initial conditions. This small-body database is updated hourly by a separate process as new measurements and discoveries are reported by the Minor Planet Center and automatically incorporated into new JPL orbit solutions. Ephemerides for other objects are derived by interpolating previously developed solutions whose trajectories have been represented in a file. For asteroids and comets, such files may be dynamically created and transferred to users, effectively recording integrator output. These small-body SPK files may then be interpolated by user software to reproduce the trajectory without duplicating the numerically integrated n-body dynamical model or PPN equations of motion. Other Horizons output is numerical and in the form of plain-text observer, vector, osculating element, or close-approach tables, typically expected be read by other software as input. About one hundred quantities can be requested in various time-scales and coordinate systems. For JPL small-body solutions, this includes statistical uncertainties derived from measurement covariance and state transition matrices. With the exception of some natural satellites, Horizons is consistent with DE405/DE406, the IAU 1976 constants, ITRF93, and IAU2009 rotational models.

76 FR 55427 - Horizon Technology Finance Corporation, et al.; Notice of Application

Science.gov (United States)

2011-09-07

.... Applicants: Horizon Technology Finance Corporation (the ``Company''), Horizon Technology Finance Management... Technology Finance Corporation, et al.; Notice of Application August 31, 2011. AGENCY: Securities and... Blass, Branch Chief, at (202) 551-6821 (Division of Investment Management, Office of Investment Company...

E(7) symmetric area of the black hole horizon

International Nuclear Information System (INIS)

Kallosh, R.; Kol, B.

1996-01-01

Extreme black holes with 1/8 of unbroken N=8 supersymmetry are characterized by the nonvanishing area of the horizon. The central charge matrix has four generic eigenvalues. The area is proportional to the square root of the invariant quartic form of E 7(7) . It vanishes in all cases when 1/4 or 1/2 of supersymmetry is unbroken. The supergravity nonrenormalization theorem for the area of the horizon in the N=8 case protects the unique U-duality invariant. copyright 1996 The American Physical Society

Gender Relations and Sexual Harassment in the Workplace: Michael Crichton's "Disclosure" as a Teaching Tool.

Science.gov (United States)

Comer, Debra R.; Cooper, Elizabeth A.

1998-01-01

Describes how to use Michael Crichton's novel "Disclosure" and the film based on it for class discussions of such issues as what constitutes sexual harassment, harassment of men, relationship between sexual harassment and power, organizational responses to harassment, and gender differences in career advancement tactics. (SK)

Solvent-free, catalyst-free aza-Michael addition of cyclohexylamine to diethyl maleate: reaction mechanism and kinetics

Czech Academy of Sciences Publication Activity Database

Bláha, Michal; Trhlíková, Olga; Podešva, Jiří; Abbrent, Sabina; Steinhart, Miloš; Dybal, Jiří; Dušková-Smrčková, Miroslava

2018-01-01

Roč. 74, č. 1 (2018), s. 58-67 ISSN 0040-4020 Institutional support: RVO:61389013 Keywords : Aza-Michael addition * solvent-free * catalyst-free Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science Impact factor: 2.651, year: 2016

LECTURE CANCELLED - “The power of collaboration - innovating collaborative relationships" by Michael Kimmel | 8 March

CERN Multimedia

2013-01-01

PLEASE NOTE THAT THIS LECTURE IS CANCELLED Friday, 8 March -  from 11.30 a.m. to 1 p.m. Globe of Science and Innovation Route de Meyrin, 1211 Geneva International Women’s Day Conference Lecture will be in English - Interpreting available in French Limited number of seats - registration is essential Reservation: + 41 22 767 76 76 or cern.reception@cern.ch Dr. Michael Kimmel, a renowned sociologist and an expert on male-female relationships, will share his latest findings on gender collaboration and how it can lead to innovation and improved relationships both at work and in the world outside. Michael Kimmel is among the world’s leading experts on male-female relationships. A Professor of Sociology at the State University of New York at Stony Brook, he is the author or editor of more than 20 books on the topic. He consults corporations, NGOs and public sector organisations all over the world on gender equity issues, including work-family balance, reducing workplac...

Horizon scanning for environmental foresight: a review of issues and approaches

Science.gov (United States)

David N. Bengston

2013-01-01

Natural resource management organizations carry out a range of activities to examine possible future conditions and trends as part of their planning process, but the distinct approach of formal horizon scanning is often a missing component of strategic thinking and strategy development in these organizations. Horizon scanning is a process for finding and interpreting...

The Horizon Is An Imaginary Line

DEFF Research Database (Denmark)

Gill, Bani; Mahendru, Radha

The Horizon Is An Imaginary Line (THIAI) is a semi-fictional illustrated account of a young Somali woman's encounters as a refugee in India. Through Maryam, we reflect on the lived experiences of alienation and marginalization as an 'outsider' on the fringes of an increasingly bordered world...

Weakly Isolated horizons: first order actions and gauge symmetries

Science.gov (United States)

Corichi, Alejandro; Reyes, Juan D.; Vukašinac, Tatjana

2017-04-01

The notion of Isolated Horizons has played an important role in gravitational physics, being useful from the characterization of the endpoint of black hole mergers to (quantum) black hole entropy. With an eye towards a canonical formulation we consider general relativity in terms of connection and vierbein variables and their corresponding first order actions. We focus on two main issues: (i) The role of the internal gauge freedom that exists, in the consistent formulations of the action principle, and (ii) the role that a 3  +  1 canonical decomposition has in the allowed internal gauge freedom. More concretely, we clarify in detail how the requirement of having well posed variational principles compatible with general weakly isolated horizons (WIHs) as internal boundaries does lead to a partial gauge fixing in the first order descriptions used previously in the literature. We consider the standard Hilbert-Palatini action together with the Holst extension (needed for a consistent 3  +  1 decomposition), with and without boundary terms at the horizon. We show in detail that, for the complete configuration space—with no gauge fixing—, while the Palatini action is differentiable without additional surface terms at the inner WIH boundary, the more general Holst action is not. The introduction of a surface term at the horizon—that renders the action for asymptotically flat configurations differentiable—does make the Holst action differentiable, but only if one restricts the configuration space and partially reduces the internal Lorentz gauge. For the second issue at hand, we show that upon performing a 3  +  1 decomposition and imposing the time gauge, there is a further gauge reduction of the Hamiltonian theory in terms of Ashtekar-Barbero variables to a U(1)-gauge theory on the horizon. We also extend our analysis to the more restricted boundary conditions of (strongly) isolated horizons as inner boundary. We show that even when the

Weakly Isolated horizons: first order actions and gauge symmetries

International Nuclear Information System (INIS)

Corichi, Alejandro; Reyes, Juan D; Vukašinac, Tatjana

2017-01-01

The notion of Isolated Horizons has played an important role in gravitational physics, being useful from the characterization of the endpoint of black hole mergers to (quantum) black hole entropy. With an eye towards a canonical formulation we consider general relativity in terms of connection and vierbein variables and their corresponding first order actions. We focus on two main issues: (i) The role of the internal gauge freedom that exists, in the consistent formulations of the action principle, and (ii) the role that a 3  +  1 canonical decomposition has in the allowed internal gauge freedom. More concretely, we clarify in detail how the requirement of having well posed variational principles compatible with general weakly isolated horizons (WIHs) as internal boundaries does lead to a partial gauge fixing in the first order descriptions used previously in the literature. We consider the standard Hilbert–Palatini action together with the Holst extension (needed for a consistent 3  +  1 decomposition), with and without boundary terms at the horizon. We show in detail that, for the complete configuration space—with no gauge fixing—, while the Palatini action is differentiable without additional surface terms at the inner WIH boundary, the more general Holst action is not. The introduction of a surface term at the horizon—that renders the action for asymptotically flat configurations differentiable—does make the Holst action differentiable, but only if one restricts the configuration space and partially reduces the internal Lorentz gauge. For the second issue at hand, we show that upon performing a 3  +  1 decomposition and imposing the time gauge, there is a further gauge reduction of the Hamiltonian theory in terms of Ashtekar–Barbero variables to a U (1)-gauge theory on the horizon. We also extend our analysis to the more restricted boundary conditions of (strongly) isolated horizons as inner boundary. We show that even when

Dr Michaels® product family (also branded as Soratinex®) versus Methylprednisolone aceponate - a comparative study of the effectiveness for the treatment of plaque psoriasis.

Science.gov (United States)

Hercogovấ, J; Fioranelli, M; Gianfaldoni, S; Chokoeva, A A; Tchernev, G; Wollina, U; Tirant, M; Novotny, F; Roccia, M G; Maximov, G K; França, K; Lotti, T

2016-01-01

As one of the most common dermatologic chronic-recurrent disease, variable therapeutic options are available today for management of psoriasis. Although topical high potency corticosteroids, alone or in association with salicylic acid or vitamin D analogues, are still considered the best treatment, they do not seem to possess the capability for a long-term control of the disease or prevent recurrences, as their side effects are major contraindications for continuative use. The aim of this study was to investigate whether Dr. Michaels® product family is comparable to methylprednisolone aceponate (MPA) as a viable alternative treatment option for the treatment and management of stable chronic plaque psoriasis. Thirty adults (13 male, 17 female, mean age 40 years) with mild to severe stable chronic plaque psoriasis, were included in the study. Patients were advised to treat the lesions of the two sides of their body (left and right) with two different unknown modalities for 8 weeks; the pack of Dr. Michaels® products on the left side (consisting of a cleansing gel, an ointment and a skin conditioner) and a placebo pack on the right side, consisting of a cleansing gel, methylprednisolone ointment and a placebo conditioner. Assessment was done using the Psoriasis Activity Severity Index (PASI) scores before treatment and after 2, 4, 6 and 8 weeks. The results achieved with the Dr. Michaels® (Soratinex®) product family for the treatment of chronic plaque psoriasis were better than the results achieved with methylprednisolone aceponate (MPA), even though quicker resolution was achieved with the steroid with 45% of patients achieving resolution within 8-10 days in comparison to 5-6 weeks in the Dr. Michaels® (Soratinex®) group. Before therapy, the mean PASI score of the LHS in Dr. Michaels® (Soratinex®) group was 13.8±4.1 SD and 14.2±4.2 SD in the RHS methylprednisolone aceponate (MPA) group. After 8 weeks of treatment 62% of the Dr. Michaels® (Soratinex

Discussion on event horizon and quantum ergosphere of evaporating black holes in a tunnelling framework

International Nuclear Information System (INIS)

Zhang Jingyi; Zhao Zheng

2011-01-01

In this paper, with the Parikh-Wilczek tunnelling framework the positions of the event horizon of the Vaidya black hole and the Vaidya-Bonner black hole are calculated, respectively. We find that the event horizon and the apparent horizon of these two black holes correspond, respectively, to the two turning points of the Hawking radiation tunnelling barrier. That is, the quantum ergosphere coincides with the tunnelling barrier. Our calculation also implies that the Hawking radiation comes from the apparent horizon.

Tandem Knoevenagel–Michael reactions in aqueous diethylamine medium: A greener and efficient approach toward bis-dimedone derivatives

Directory of Open Access Journals (Sweden)

Abdullah Mohammed Al-Majid

2017-02-01

The use of inexpensive, eco-friendly and readily available reagents, easy work-up, and high purity products makes the procedure a convenient and robust method for the synthesis of tandem Knoevenagel–Michael adducts.

New Horizons in Gravity: The Trace Anomaly, Dark Energy and Condensate Stars

CERN Document Server

Mottola, Emil

2010-01-01

General Relativity receives quantum corrections relevant at macroscopic distance scales and near event horizons. These arise from the conformal scalar degrees of freedom in the extended effective field theory of gravity generated by the trace anomaly of massless quantum fields in curved space. The origin of these conformal scalar degrees of freedom as massless poles in two-particle intermediate states of anomalous amplitudes in flat space is exposed. At event horizons the conformal anomaly scalar degrees of freedom can have macroscopically large effects on the geometry, potentially removing the classical event horizon of black hole and cosmological spacetimes, replacing them with a quantum boundary layer where the effective value of the gravitational vacuum energy density can change. In the effective theory, the cosmological term becomes a dynamical condensate, whose value depends upon boundary conditions near the horizon. In the conformal phase where the anomaly induced fluctutations dominate, and the conden...

VMware Horizon Mirage essentials

CERN Document Server

Von Oven, Peter

2013-01-01

This book provides a practical, step-by-step approach to teach you how to build a successful infrastructure.This book is perfect for desktop administrators who want to deploy a solution to centrally manage their endpoint images across their entire estate using VMware Horizon Mirage. You need to have some experience in desktop image management using Microsoft Windows operating systems and Windows applications, as well as be familiar with Active Directory, SQL, IIS, and general server infrastructure relating to supporting end users.

Expanding Your Horizon 2015

CERN Multimedia

Kaltenhauser, Kristin

2015-01-01

Expanding your horizons is a bi-annual “Science Day” for girls aged 11 to 14, held at the University of Geneva on 14 November. The girls had the opportunity to take part in hands-on workshops held by local professional women in the field of science, mathematics, engineering and technology. For the fourth time, CERN was part of this event, offering three workshops as well as a booth at the Discovery Fair, including Higgnite, an interactive visualization of the Higgs Field.

Black Hole Entropy from Bondi-Metzner-Sachs Symmetry at the Horizon.

Science.gov (United States)

Carlip, S

2018-03-09

Near the horizon, the obvious symmetries of a black hole spacetime-the horizon-preserving diffeomorphisms-are enhanced to a larger symmetry group with a three-dimensional Bondi-Metzner-Sachs algebra. Using dimensional reduction and covariant phase space techniques, I investigate this augmented symmetry and show that it is strong enough to determine the black hole entropy in any dimension.

The case for increasing returns (2: the methods of planning horizons

Directory of Open Access Journals (Sweden)

Frederic B. Jennings Jr.

2016-05-01

Full Text Available In neoclassical economics, substitution assumptions support equilibrium models in closed systems shunning interdependence. On these grounds an array of frames show outcomes as stable, efficient, unique and determinate. Heterodox economists say equilibrium models sidestep practical knowledge and the rich reality of economic behavior. Rigor or realism, mainstream or radical, ecological, institutional, socio-cultural: economics invites a wide diversity of assumptions, once short-term models of substitution are opened to question. The answers are blurred by applications; there is clarity in a simplicity shielded from mundane detail. This paper addresses the methodological impact of planning horizons, increasing returns and complementarity, and their proper representation in economic constructions. Horizonal economics can be construed as extending orthodox standards into a realm of time, but for its subtler ramifications. Increasing returns make our relations complementary and not substitutional, loosening the tight deductions from mainstream models of choice. The horizonal extension of our received theory of price applies time to cost and demand curves, showing Marshallian scissors (supply and demand cut outward and downward with expanded horizons. Static conceptions appear in horizonal groups, suggesting complete theories of price should specify agents’ horizons, with no further radical impact: the trouble emerges with increasing returns and complementarity. Horizons stem from unbounded causality; if all we do ripples outward forever in nature and society, the relevant field of inquiry for economics is interdependent: this is the case for bounded rationality as an analytical limit to economic conceptions. In turn, interdependence suggests a use of network constructs to frame complex systemic cascades, and networks open a door to complementarity and increasing returns in transport and information exchange. The gaping maw of increasing returns and

Near-horizon brane-scan revived

International Nuclear Information System (INIS)

Duff, M.J.

2009-01-01

In 1987 two versions of the brane-scan of D-dimensional super p-branes were put forward. The first pinpointed those (p,D) slots consistent with kappa-symmetric Green-Schwarz type actions; the second generalized the membrane at the end of the universe idea to all those superconformal groups describing p-branes on the boundary of AdS p+2 xS D-p-2 . Although the second version predicted D3- and M5-branes in addition to those of the first, it came unstuck because the 1/2 BPS solitonic branes failed to exhibit the required symmetry enhancement in the near-horizon limit, except in the non-dilatonic cases (p=2,D=11), (p=3,D=10) and (p=5,D=11). Just recently, however, it has been argued that the fundamental D=10 heterotic string does indeed display a near-horizon enhancement to OSp(8|2) as predicted by the brane-scan, provided α' corrections are taken into account. If this logic could be extended to the other strings and branes, it would resolve this 21-year-old paradox and provide a wealth of new AdS/CFT dualities, which we tabulate

An Interview with Michael Betancourt, author of Agnotology & Crisis in Digital Capitalism

OpenAIRE

Sean Scanlan; Michael Betancourt

2015-01-01

Sean Scanlan, NANO's editor, interviews artist, curator, art historian and critical theorist Michael Betancourt to discuss the nature of agnotology, a term that means the “creation of uncertainty and ambivalent ‘fact’; it is a competitive tool incompatible with the idealized ‘free market’ of capitalism.” Betancourt is skeptical of Big Data and the ways that the consumers who unknowingly “produce” data for business interpretation are increasingly becoming transformed into a “token of exchange ...

POLYETHYLENEIMINE (PEI ON SILICA AS CATALYST IN KNOEVENAGEL AND MICHAEL REACTIONS

Directory of Open Access Journals (Sweden)

FATIHA ZAOUI

2017-03-01

Full Text Available After the synthesis of polyethylenimine supported on silica, it has been used as a new and efficient catalyst in Knoevenagel and Michael condensations. The presence of the polyethylenimine in the catalytic system together with silica displays an acido-basic character allows a better catalytic activity in the condensations. Carried out under microwave irradiation, without organic solvent and during short time, the syntheses are respectful towards green chemistry. The solid catalyst can be easily reused. This catalyst has the acido-basic character at the same time.

Action at the Horizon: Chandra/EHT Observations of Sgr A*

Science.gov (United States)

Neilsen, Joseph

2017-09-01

In April 2017, the Event Horizon Telescope will observe Sgr A* with imaging quality sufficient to resolve the shadow of the black hole, while providing a close-up view of accretion at the horizon. As Sgr A* is a well-known source of X-ray flares, coordinated Chandra/EHT observations offer an incredible opportunity: a chance to observe structures (e.g., hotspots) near the event horizon while tracking their high-energy variability. In anticipation of a follow-up campaign in 2018, we are requesting 4x33 ks Chandra observations of Sgr A* to be coordinated with EHT. This campaign will double our chances of simultaneous flares. We will search for flares and hotspots, provide priors for EHT image reconstruction, and track any activity associated with the closest approach of the massive star S0-2.

NHEG mechanics: laws of near horizon extremal geometry (thermo)dynamics

International Nuclear Information System (INIS)

Hajian, K.; Seraj, A.; Sheikh-Jabbari, M.M.

2014-01-01

Near Horizon Extremal Geometries (NHEG) are solutions to gravity theories with SL(2,ℝ)×U(1) N (for some N) symmetry, are smooth geometries and have no event horizon, unlike black holes. Following the ideas by R. M. Wald, we derive laws of NHEG dynamics, the analogs of laws of black hole dynamics for the NHEG. Despite the absence of horizon in the NHEG, one may associate an entropy to the NHEG, as a Noether-Wald conserved charge. We work out “entropy” and “entropy perturbation” laws, which are respectively universal relations between conserved Noether charges corresponding to the NHEG and a system probing the NHEG. Our entropy law is closely related to Sen’s entropy function. We also discuss whether the laws of NHEG dynamics can be obtained from the laws of black hole thermodynamics in the extremal limit

Komparativistlikke ja kultuuriteaduslikke ärgitusi Baltimaade germanistikale / Michael Schwidtal ; saksa keelest tõlkinud Vahur Aabrams

Index Scriptorium Estoniae

Schwidtal, Michael

2001-01-01

3. - 5. sept. 2001 toimus Riias sümpoosion "Unter diesem braunen Himmel. Jakob Michael Reinhold Lenz und die deutsche Literatur des Baltikums", 7. - 9. sept. Tartus "Torm ja tung Liivimaal. Mässu mudelid", pühendatud J. M. R. Lenzi ja Kristian Jaak Petersoni loomingule. Ülevaade

N-Heterocyclic-Carbene-Catalysed Diastereoselective Vinylogous Mukaiyama/Michael Reaction of 2-(Trimethylsilyloxy)furan and Enones

KAUST Repository

Wang, Ying; Du, Guang Fen; Xing, Fen; Huang, Kuo-Wei; Dai, Bin; He, Lin

2015-01-01

N-heterocyclic carbenes have been utilised as highly efficient nucleophilic organocatalysts to mediate vinylogous Mukaiyama/Michael reactions of 2-(trimethylsilyloxy)furan with enones to afford γ-substituted butenolides in 44-99% yield with 3:1-32:1 diastereoselectivity. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

N-Heterocyclic-Carbene-Catalysed Diastereoselective Vinylogous Mukaiyama/Michael Reaction of 2-(Trimethylsilyloxy)furan and Enones

KAUST Repository

Wang, Ying

2015-10-15

N-heterocyclic carbenes have been utilised as highly efficient nucleophilic organocatalysts to mediate vinylogous Mukaiyama/Michael reactions of 2-(trimethylsilyloxy)furan with enones to afford γ-substituted butenolides in 44-99% yield with 3:1-32:1 diastereoselectivity. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Regional Variability of Cd, Hg, Pb and C Concentrations in Different Horizons of Swedish Forest Soils

International Nuclear Information System (INIS)

Alriksson, A.

2001-01-01

Contents of cadmium (Cd), mercury (Hg), lead (Pb) and carbon(C) in the O, B and C horizons of podzolized forest soils in Sweden were surveyed. Concentrations and storage of Cd, Hg and Pb in the O and B horizons were high in southern Sweden and gradually decreased towards the north, though with considerable local variability. This pattern reflects the influence of anthropogenic emissions of these metals, as well as the effects of soil-forming processes. Parent till material, as represented by the C horizon concentration of the respective metal, accounted for little of the variation in metal concentration in the O horizon. For Cd and Pb, the correlations were not significant or slightly negative (R 2 = 0.12 and 0.09 respectively) depending on region, while for Hg the correlation was not significant or slightly positive (R 2 = 0.03 and 0.08). Furthermore, parent till material accounted for more of the variation in metal concentrations in the B horizons in the northern part of Sweden than in the middle and southernmost parts, where the concentration of total carbon had more influence. The correlation between the metal concentrations in the B and C horizon was strongest for Pb (R 2 = 0.63 and 0.36 in the two northernmost regions), lower for Cd (R 2 = 0.19 and 0.16) and not significant for Hg. For all soil horizons, total C concentration accounted for much of the variation in Hg concentration in particular (O-horizon R 2 = 0.15-0.69, B horizon R 2 = 0.36-0.50, C horizon R 2 = 0.23-0.50 and ns in one region). Ratios of metal concentrations between the B and C horizons were highest for Hg(maximum value of 30), indicating a relatively larger addition or retention of Hg compared to Cd and Pb (maximum value of 10)in the B horizon. This study indicate that factors other than parent material account for the large scale variation in O horizon concentrations of metals but patterns correspond well with those of atmospheric deposition of heavy metals and acidifying substances

Holographic stress-energy tensor near the Cauchy horizon inside a rotating black hole

Science.gov (United States)

Ishibashi, Akihiro; Maeda, Kengo; Mefford, Eric

2017-07-01

We investigate a stress-energy tensor for a conformal field theory (CFT) at strong coupling inside a small five-dimensional rotating Myers-Perry black hole with equal angular momenta by using the holographic method. As a gravitational dual, we perturbatively construct a black droplet solution by applying the "derivative expansion" method, generalizing the work of Haddad [Classical Quantum Gravity 29, 245001 (2012), 10.1088/0264-9381/29/24/245001] and analytically compute the holographic stress-energy tensor for our solution. We find that the stress-energy tensor is finite at both the future and past outer (event) horizons and that the energy density is negative just outside the event horizons due to the Hawking effect. Furthermore, we apply the holographic method to the question of quantum instability of the Cauchy horizon since, by construction, our black droplet solution also admits a Cauchy horizon inside. We analytically show that the null-null component of the holographic stress-energy tensor negatively diverges at the Cauchy horizon, suggesting that a singularity appears there, in favor of strong cosmic censorship.

Astrometry of 2014MU69 for New Horizons encounter

Science.gov (United States)

Buie, Marc

2017-08-01

We propose 12 orbits of time to make high-precision astrometric measurments of the New Horizons extendedmission target, (486958) 2014MU69. These observations are in direct support of the navigation of New Horizonsleading up to its encounter in Jan 2019. These visits represent an optimized plan for improved orbit estimates that willcomplete as the target becomes directly observable by New Horizons. This astrometry is a key element leadingup to a close investigation of a Cold-Classical Kuiper Belt Object, one of the most primitive members of our solarsystem.

Horizon strings and interior states of a black hole

Directory of Open Access Journals (Sweden)

K.P. Yogendran

2015-11-01

Full Text Available We provide an explicit construction of classical strings that have endpoints on the horizons of the 2D Lorentzian black hole. We argue that this is a dual description of geodesics that are localized around the horizon which are the Lorentzian counterparts of the winding strings of the Euclidean black hole (the cigar geometry. Identifying these with the states of the black hole, we can expect that issues of black hole information loss can be posed sharply in terms of a fully quantizable string theory.

Review: Barr, Michael and Zlatko Skrbiš (2008, Constructing Singapore. Elitism, Ethnicity and the Nation-Building Project

Directory of Open Access Journals (Sweden)

Boris Michel

2009-01-01

Full Text Available Review of the monograph: Barr, Michael and Zlatko Skrbiš, Constructing Singapore. Elitism, Ethnicity and the Nation-Building Project, Copenhagen: NIAS Press, 2008, ISBN 978-87-7694-029-4, 304 pages

Synthetic genome engineering forging new frontiers for wine yeast.

Science.gov (United States)

Pretorius, Isak S

2017-02-01

Over the past 15 years, the seismic shifts caused by the convergence of biomolecular, chemical, physical, mathematical, and computational sciences alongside cutting-edge developments in information technology and engineering have erupted into a new field of scientific endeavor dubbed Synthetic Biology. Recent rapid advances in high-throughput DNA sequencing and DNA synthesis techniques are enabling the design and construction of new biological parts (genes), devices (gene networks) and modules (biosynthetic pathways), and the redesign of biological systems (cells and organisms) for useful purposes. In 2014, the budding yeast Saccharomyces cerevisiae became the first eukaryotic cell to be equipped with a fully functional synthetic chromosome. This was achieved following the synthesis of the first viral (poliovirus in 2002 and bacteriophage Phi-X174 in 2003) and bacterial (Mycoplasma genitalium in 2008 and Mycoplasma mycoides in 2010) genomes, and less than two decades after revealing the full genome sequence of a laboratory (S288c in 1996) and wine (AWRI1631 in 2008) yeast strain. A large international project - the Synthetic Yeast Genome (Sc2.0) Project - is now underway to synthesize all 16 chromosomes (∼12 Mb carrying ∼6000 genes) of the sequenced S288c laboratory strain by 2018. If successful, S. cerevisiae will become the first eukaryote to cross the horizon of in silico design of complex cells through de novo synthesis, reshuffling, and editing of genomes. In the meantime, yeasts are being used as cell factories for the semi-synthetic production of high-value compounds, such as the potent antimalarial artemisinin, and food ingredients, such as resveratrol, vanillin, stevia, nootkatone, and saffron. As a continuum of previously genetically engineered industrially important yeast strains, precision genome engineering is bound to also impact the study and development of wine yeast strains supercharged with synthetic DNA. The first taste of what the future

New eco-friendly animal bone meal catalysts for preparation of chalcones and aza-Michael adducts

Directory of Open Access Journals (Sweden)

Riadi Yassine

2012-06-01

Full Text Available Abstract Two efficient reactions were successfully carried out using Animal Bone Meal (ABM and potassium fluoride or sodium nitrate doped ABMs as new heterogeneous catalysts under very mild conditions. After preparation and characterization of the catalysts, we first report their use in a simple and convenient synthesis of various chalcones by Claisen–Schmidt condensation and then in an aza-Michael addition involving several synthesized chalcones with aromatic amines. All the reactions were carried out at room temperature in methanol; the chalcone synthesis was also achieved in water environment under microwave irradiation. Doping ABM enhances the rate and yield at each reaction. Catalytic activities are discussed and the ability to re-use the ABM is demonstrated. Results For Claisen–Schmidt the use of ABM alone, yields never exceeded 17%. In each entry, KF/ABM and NaNO3/ABM (79-97% gave higher yields than using ABM alone under thermic condition. Also the reaction proceeded under microwave irradiation in good yields (72-94% for KF/ABM and 81-97% for NaNO3/ABM and high purity. For aza-Michael addition the use of ABM doped with KF or NaNO3 increased the catalytic activity remarkably. The very high yields could be noted (84-95% for KF/ABM and 81-94% for NaNO3/ABM. Conclusion The present method is an efficient and selective procedure for the synthesis of chalcones an aza-Michael adducts. The ABM and doped ABMs are a new, inexpensive and attractive solid supports which can contribute to the development of catalytic processes and reduced environmental problems.

Preferential Flow Paths Allow Deposition of Mobile Organic Carbon Deep into Soil B Horizons

Science.gov (United States)

Marin-Spiotta, E.; Chadwick, O.; Kramer, M. G.

2009-12-01

Most of our understanding of soil carbon (C) dynamics derives from the top 10 to 20 cm, although globally the majority of the bulk soil C pool is found below those depths. Mineral associated C in deep soil is more stable than that held in surface horizons, and its long-term persistence may contribute to sequestration of anthropogenic C. Carbon can enter deep soil horizons in multiple ways: through biologically-mediated or abiotic physical mixing, illuviation, root inputs, or through a physical disturbance that would cause the burial of an originally shallow organic horizon. In this study, we investigated the role of dissolved organic matter (DOM) in the transport and stabilization of soil C in tropical rainforest volcanic soils, where high rainfall, a highly productive forest, and dominance of highly reactive, non-crystalline minerals contribute to large soil C stocks at depth with long mean residence times. DOM plays an important role in many biological and chemical processes in soils, including nutrient transfer within and across ecosystems. Carbon storage in these soils is linked to movement of both DOC and particulate organic C along infiltration pathways. Climate and soil mineralogical properties create the right conditions for C to be pumped from the organic horizons where microbial activity is highest, to deep mineral horizons, where the potential for stabilization is greatest. High rainfall preserves hydrated short-range order minerals that are subject to strong shrinkage during occasional drought periods. The resulting cracks in subsurface B horizons become pathways for DOM complexed with Fe and Al moving in soil solution during subsequent wet periods. Preferential flow of these organically rich solutes and/or colloids moves C to depth where C, Fe and Al are preferentially deposited on near-vertical crack surfaces and along near-horizonal flow surfaces at horizon boundaries. Long-term deposition forms discontinuous Fe- and OM-cemented lamella that serve to

Deepwater Horizon Seafood Safety Oracle Database (2010)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — In 2010, the Deepwater Horizon oil spill occurred in the Gulf of Mexico. In response to this spill, the National Marine Fisheries Service initiated a data collection...

Cosmological horizons and reconstruction of quantum field theories

Energy Technology Data Exchange (ETDEWEB)

Dappiaggi, C.; Pinamonti, N. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik]|[Trento Univ., Povo (Italy). Istituto Nazionale di Alta Matematica ' ' F. Severi' ' - GNFM; Moretti, V. [Trento Univ. (Italy). Dipt. di Matematica]|[Istituto Nazionale di Fisica Nucleare - Gruppo Collegato di Trento, Povo (Italy)

2007-12-15

As a starting point for this manuscript, we remark how the cosmological horizon of a certain class of Friedmann-Robertson-Walker backgrounds shares some non trivial geometric properties with null infinity in an asymptotically flat spacetime. Such a feature is generalized to a larger class of expanding spacetimes M admitting a geodesically complete cosmological horizon J{sup -} common to all co-moving observers. This property is later exploited in order to recast, in a cosmological background, some recent results for a linear scalar quantum field theory in spacetimes asymptotically flat at null infinity. Under suitable hypotheses on M - valid for de Sitter spacetime and some other FRW spacetimes obtained by perturbing deSitter space - the algebra of observables for a Klein-Gordon field is mapped into a subalgebra of the algebra of observables W(J{sup -}) constructed on the cosmological horizon. There is exactly one pure quasifree state {lambda} on W(J{sup -}) which fulfills a suitable energy positivity condition with respect to a generator related with the cosmological time displacements. Furthermore {lambda} induces a preferred physically meaningful quantum state {lambda}{sub M} for the quantum theory in the bulk. If M admits a timelike Killing generator preserving J{sup -}, then the associated self-adjoint generator in the GNS representation of {lambda}{sub M} has positive spectrum (i.e. energy). Moreover {lambda}{sub M} turns out to be invariant under every symmetry of the bulk metric which preserves the cosmological horizon. In the case of an expanding de Sitter spacetime, {lambda}{sub M} coincides with the Euclidean (Bunch-Davies) vacuum state, hence being Hadamard in this case. Remarks on the validity of the Hadamard property for {lambda}{sub M} in more general spacetimes are presented. (orig.)

Tagasipöördumine esteetika juurde = Return to aesthetics / Keith Moxey, Michael Ann Holly ; interv. Anu Allas

Index Scriptorium Estoniae

Moxey, Keith

2007-01-01

Ameerika kunstiajaloolased Keith Moxey ning Michael Ann Holly tutvustavad uut lähenemist kunstiajaloole (new art history). Nn. naasmine esteetika juurde tähendab püüet integreerida kunstiajalukku ja -teooriasse uuesti ja tugevamalt kunstiteos

The big picture : What the Baltics may learn from Ireland's success story / Michael Bourke ; interv. Maris Biezaitis

Index Scriptorium Estoniae

Bourke, Michael

2002-01-01

Ilmunud ka: Baltiiskii kurss 2002/Zima/Vesna nr. 20 lk. 14-17. Iirimaa aukonsul Lätis, Michael Joseph Bourke arutleb Iirimaa majandusedu teemal ning pakub välja, mida Baltimaad saaksid sellest õppida. Tabel, diagramm. Lisa

arXiv Effective horizons, junction conditions and large-scale magnetism

CERN Document Server

Giovannini, Massimo

2017-08-05

The quantum mechanical generation of hypermagnetic and hyperlectric fields in four-dimensional conformally flat background geometries rests on the simultaneous continuity of the effective horizon and of the extrinsic curvature across the inflationary boundary. The junction conditions for the gauge fields are derived in general terms and corroborated by explicit examples with particular attention to the limit of a sudden (but nonetheless continuous) transition of the effective horizon. After reducing the dynamics to a pair of integral equations related by duality transformations, we compute the power spectra and deduce a novel class of logarithmic corrections which turn out to be, however, numerically insignificant and overwhelmed by the conductivity effects once the gauge modes reenter the effective horizon. In this perspective the magnetogenesis requirements and the role of the postinflationary conductivity are clarified and reappraised. As long as the total duration of the inflationary phase is nearly minim...

Identifying Disruptive Technologies in Design: Horizon Scanning in the Early Stages of Design

DEFF Research Database (Denmark)

Ernstsen, Sidsel Katrine; Thuesen, Christian; Larsen, Laurids Rolighed

Technology development is accelerating, driving disruption. Design is seen as key differentiator in creating innovative offerings but few design methods consider future technologies explicitly. In this article, we explore how a foresight method, namely horizon scanning, may be applied in a design...... context to anticipate disruption of construction. By means of a 3-step horizon scan, we identify 133 potentially disruptive technologies from across industries. We find that when preparing for disruption, design may benefit from the future-oriented and technology-focused features of horizon scanning....

Horror movie aspects and experimentation in Michael Jackson’s Thriller music video

OpenAIRE

Vargas, Herom; Universidade Municipal de São Caetano do Sul - USCS; Gonçalves, Rafael; Universidade Municipal de São Caetano do Sul - USCS

2016-01-01

This article analyzes the use of elements from the horror fi lm genre in the music video Thriller (1982), by Michael Jackson, as experimentation within the field of pop music. Based on the semiotics of culture, grounded on the concepts of cultural text, semiosphere, border and modeling, developed by Iuri Lotman, the analysis identified innovations in the use of horror as humor and, in the music, modeling of creatures, moving among horror, the fantastic and the reality.Keywords: horror, music ...

New Worlds, New Horizons in Astronomy and Astrophysics

National Research Council Canada - National Science Library

2010-01-01

.... Based on a broad and comprehensive survey of scientific opportunities, infrastructure, and organization in a national and international context, New Worlds, New Horizons in Astronomy and Astrophysic...

Thomas DaCosta Kaufmann and Michael North (eds., Mediating Netherlandish Art and Material Culture in Asia

Directory of Open Access Journals (Sweden)

Claartje Rasterhoff

2015-12-01

Full Text Available Book notice of: Thomas DaCosta Kaufmann and Michael North (eds., Mediating Netherlandish Art and Material Culture in Asia (Amsterdam Studies in the Dutch Golden Age Amsterdam, Amsterdam University Press, 2014. 348 pp. ISBN 978-90-8964-569-2. € 99,00.

Does horizon entropy satisfy a quantum null energy conjecture?

Science.gov (United States)

Fu, Zicao; Marolf, Donald

2016-12-01

A modern version of the idea that the area of event horizons gives 4G times an entropy is the Hubeny-Rangamani causal holographic information (CHI) proposal for holographic field theories. Given a region R of a holographic QFTs, CHI computes A/4G on a certain cut of an event horizon in the gravitational dual. The result is naturally interpreted as a coarse-grained entropy for the QFT. CHI is known to be finitely greater than the fine-grained Hubeny-Rangamani-Takayanagi (HRT) entropy when \\partial R lies on a Killing horizon of the QFT spacetime, and in this context satisfies other non-trivial properties expected of an entropy. Here we present evidence that it also satisfies the quantum null energy condition (QNEC), which bounds the second derivative of the entropy of a quantum field theory on one side of a non-expanding null surface by the flux of stress-energy across the surface. In particular, we show CHI to satisfy the QNEC in 1  +  1 holographic CFTs when evaluated in states dual to conical defects in AdS3. This surprising result further supports the idea that CHI defines a useful notion of coarse-grained holographic entropy, and suggests unprecedented bounds on the rate at which bulk horizon generators emerge from a caustic. To supplement our motivation, we include an appendix deriving a corresponding coarse-grained generalized second law for 1  +  1 holographic CFTs perturbatively coupled to dilaton gravity.

A nuclear reactor power controller using a receding horizon control method

International Nuclear Information System (INIS)

Na, Man Gyun; Sim, Young Rok

2001-01-01

A receding horizon control method is applied to design a fully automatic controller for thermal power in a reactor core. The basic concept of the receding horizon control is to solve an optimization problem for a finite future at current time and to implement as the current control input the first optimal control input among the solutions of the finite time steps. The procedure is then repeated at each subsequent instant. The receding horizon controller is designed so that the difference between the output and the desired output is minimized and the variation of the control rod position is small. The nonlinear PWR plant model (nonlinear point kinetics equation with six delayed neutron groups and the lumped thermal-hydraulic balance equations) was used to verify the proposed controller of reactor power. And a controller design model used for designing the receding horizon controller was obtained by applying a parameter estimation algorithm. From numerical simulation results, the performances of this controller for the 5%/min ramp increase or decrease of a desired load and its 10% step increase or decrease which are design requirements are proved to be excellent

Evolution of the cosmological horizons in a universe with countably infinitely many state equations

Energy Technology Data Exchange (ETDEWEB)

Margalef-Bentabol, Berta; Cepa, Jordi [Departamento de Astrofísica, Universidad de la Laguna, E-38205 La Laguna, Tenerife (Spain); Margalef-Bentabol, Juan, E-mail: bmb@cca.iac.es, E-mail: juanmargalef@estumail.ucm.es, E-mail: jcn@iac.es [Facultad de Ciencias Matemáticas, Universidad Complutense de Madrid, E-28040 Madrid (Spain)

2013-02-01

This paper is the second of two papers devoted to the study of the evolution of the cosmological horizons (particle and event horizons). Specifically, in this paper we consider a general accelerated universe with countably infinitely many constant state equations, and we obtain simple expressions in terms of their respective recession velocities that generalize the previous results for one and two state equations. We also provide a qualitative study of the values of the horizons and their velocities at the origin of the universe and at the far future, and we prove that these values only depend on one dominant state equation. Finally, we compare both horizons and determine when one is larger than the other.

Asymmetric synthesis of α-amino acids via homologation of Ni(II) complexes of glycine Schiff bases. Part 3: Michael addition reactions and miscellaneous transformations.

Science.gov (United States)

Aceña, José Luis; Sorochinsky, Alexander E; Soloshonok, Vadim

2014-09-01

The major goal of this review is a critical discussion of the literature data on asymmetric synthesis of α-amino acids via Michael addition reactions involving Ni(II)-complexes of amino acids. The material covered is divided into two conceptually different groups dealing with applications of: (a) Ni(II)-complexes of glycine as C-nucleophiles and (b) Ni(II)-complexes of dehydroalanine as Michael acceptors. The first group is significantly larger and consequently subdivided into four chapters based on the source of stereocontrolling element. Thus, a chiral auxiliary can be used as a part of nucleophilic glycine Ni(II) complex, Michael acceptor or both, leading to the conditions of matching vs. mismatching stereochemical preferences. The particular focus of the review is made on the practical aspects of the methodology under discussion and mechanistic considerations.

Deep Water Horizon (HB1006, EK60)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monitor and measure the biological, chemical, and physical environment in the area of the oil spill from the deep water horizon oil rig in the Gulf of Mexico. A wide...

A general thermodynamical description of the event horizon in the FRW universe

International Nuclear Information System (INIS)

Tu, Fei-Quan; Chen, Yi-Xin

2016-01-01

The Friedmann equation in the Friedmann-Robertson-Walker (FRW) universe with any spatial curvature is derived from the first law of thermodynamics on the event horizon. The key idea is to redefine a Hawking temperature on the event horizon. Furthermore, we obtain the evolution equations of the universe including the quantum correction and explore the evolution of the universe in f(R) gravity. In addition, we also investigate the generalized second law of thermodynamics in Einstein gravity and f(R) gravity. This perspective also implies that the first law of thermodynamics on the event horizon has a general description in respect of the evolution of the FRW universe. (orig.)

New Horizons Reconnaissance of the Pluto-Charon System and the Kuiper Belt

CERN Document Server

Russell, C. T

2009-01-01

The New Horizons mission provides the first in situ reconnaissance of the Pluto-Charon System and the Kuiper belt, arguably the last frontier of solar system exploration. This book describes the mission, its objectives, expected results, and instruments in articles written by the scientists and engineers most closely involved. The New Horizons mission is expected to return unique observations and discoveries, which will revolutionize our understanding of the formation of the solar system. This volume is aimed at researchers and graduate students active in planetary science and space exploration, and all other potential users of data obtained by the instruments on board the New Horizons mission.

Horizon structure of rotating Bardeen black hole and particle acceleration

International Nuclear Information System (INIS)

Ghosh, Sushant G.; Amir, Muhammed

2015-01-01

We investigate the horizon structure and ergosphere in a rotating Bardeen regular black hole, which has an additional parameter (g) due to the magnetic charge, apart from the mass (M) and the rotation parameter (a). Interestingly, for each value of the parameter g, there exists a critical rotation parameter (a = a E ), which corresponds to an extremal black hole with degenerate horizons, while for a < a E it describes a non-extremal black hole with two horizons, and no black hole for a > a E . We find that the extremal value a E is also influenced by the parameter g, and so is the ergosphere. While the value of a E remarkably decreases when compared with the Kerr black hole, the ergosphere becomes thicker with the increase in g.We also study the collision of two equal mass particles near the horizon of this black hole, and explicitly show the effect of the parameter g. The center-of-mass energy (E CM ) not only depend on the rotation parameter a, but also on the parameter g. It is demonstrated that the E CM could be arbitrarily high in the extremal cases when one of the colliding particles has a critical angular momentum, thereby suggesting that the rotating Bardeen regular black hole can act as a particle accelerator. (orig.)

Event Horizon Telescope observations as probes for quantum structure of astrophysical black holes

Science.gov (United States)

Giddings, Steven B.; Psaltis, Dimitrios

2018-04-01

The need for a consistent quantum evolution for black holes has led to proposals that their semiclassical description is modified not just near the singularity, but at horizon or larger scales. If such modifications extend beyond the horizon, they influence regions accessible to distant observation. Natural candidates for these modifications behave like metric fluctuations, with characteristic length scales and timescales set by the horizon radius. We investigate the possibility of using the Event Horizon Telescope to observe these effects, if they have a strength sufficient to make quantum evolution consistent with unitarity, without introducing new scales. We find that such quantum fluctuations can introduce a strong time dependence for the shape and size of the shadow that a black hole casts on its surrounding emission. For the black hole in the center of the Milky Way, detecting the rapid time variability of its shadow will require nonimaging timing techniques. However, for the much larger black hole in the center of the M87 galaxy, a variable black-hole shadow, if present with these parameters, would be readily observable in the individual snapshots that will be obtained by the Event Horizon Telescope.

Michael Longley’s Father: Memory, Mourning and History

Directory of Open Access Journals (Sweden)

Barry Sloan

2012-03-01

Full Text Available Michael Longley’s father has been a recurring presence in the poet’s work from his earliest to his most recent collection. This paper examines the exceptional strength of that bond reflected in the varied and changing ways in which the poet has responded to it – memorizing and mourning his loss; discovering through his father’s First World War stories a means of memorialising loss of life in contemporary conflicts and a way of facing the history of the twentieth century; confronting his own ageing and sense of mortality; and marking the specific, but also representative, generational history of his family. Close readings of key poems are offered to highlight Longley’s skills in meeting his own exacting standards of aesthetic propriety and moral and social responsibility for writers of elegy in order to avoid either exploitation of tragedy and loss, or facile gestures of consolation.

Changes in diversity, biomass and abundance of soil macrofauna, Parrotio-Carpinetum forest at organic and semi-organic horizons

Directory of Open Access Journals (Sweden)

Masomeh Izadi

2016-07-01

Full Text Available Present study evaluates diversity, abundance and biomass of soil macrofauna in organic and semi-organic horizons in Parrotia persica-Carpinus betulus forest in Shast kola area. Totally 70 sample points were randomly selected from organic and semi-organic horizons then sampling was done by a rectangle 100 cm2 area. Soil macrofauna were separated from soil samples by hand sorting and using Berlese funnel then dried at 60°C for 72h and weighted in 0.001 gr. With using taxonomic classification key, thirteen macrofauna orders were identified. Most of abundance of soil macrofauna in both soil horizons were allocated to Millipedes order. Changes in diversity, abundance and biomass of macrofauna in both soil horizons were calculated. The results showed Shannon diversity index, Simpson evenness and Margalef richness indices in semi-organic horizon were more than organic horizon. Abundance and biomass of macrofauna in semi-organic horizon were more than organic horizon.

A deep organic horizon, evidence of inter-stadium Wurm II-III in forest of Fontainebleau

International Nuclear Information System (INIS)

Robin, A.M.; Barthelemy, L.

1996-01-01

A black horizon with 33 % organic matter and certainly of pedologic origin, at 4 m depth and cryo-perturbed or displaced, was found to be 29-30,000 years old by 14 C dating. The pollen spectrum indicated vegetation representative of his period. The 4 m of overlying sediment are a repetition of different layers, submitted to pedogenic processes. Clayey-sandy horizons were sometimes markedly cryo-perturbed and/or displaced or truncated. The pollen diagram as a whole showed a cycle of sterile horizons and horizons bearing the same vegetation. (authors). 9 refs., 2 figs., 1 tab

Theoretical study on the reaction mechanisms of Michael chirality addition between propionaldehyde and nitroalkene catalyzed by an enantioselective catalyst.

Science.gov (United States)

Zhou, Xinming; Li, Ling; Sun, Xuejun; Wang, Yajun; Du, Dongmei; Fu, Hui

2018-06-01

The asymmetric Michael addition between propionaldehyde and nitroalkene catalyzed by 8-(ethoxycarbonyl)-1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indole-2-carboxylic acid has obtained relatively high yields and excellent enantioselectivities at room temperature. In this study, the molecular structures and optical activity of the most stable conformation I are optimized at B3LYP/6-311++ G(d,p) level. We find that levorotatory conformation I catalyzing the same Michael addition can produce laevo-product A and dextrorotatory conformation I' can obtain the dextral-product A'. These results have guiding significance for further studying on the new chemzymes and the mechanism of the obtained different chiral products. © 2018 Wiley Periodicals, Inc.

Scalar hairy black holes and scalarons in the isolated horizons formalism

International Nuclear Information System (INIS)

Corichi, Alejandro; Nucamendi, Ulises; Salgado, Marcelo

2006-01-01

The Isolated Horizons (IH) formalism, together with a simple phenomenological model for colored black holes has been used to predict nontrivial formulas that relate the ADM mass of the solitons and hairy Black Holes of Gravity-Matter system on the one hand, and several horizon properties of the black holes in the other. In this article, the IH formalism is tested numerically for spherically symmetric solutions to an Einstein-Higgs system where hairy black holes were recently found to exist. It is shown that the mass formulas still hold and that, by appropriately extending the current model, one can account for the behavior of the horizon properties of these new solutions. An empirical formula that approximates the ADM mass of hairy solutions is put forward, and some of its properties are analyzed

Cool horizons lead to information loss

Science.gov (United States)

Chowdhury, Borun D.

2013-10-01

There are two evidences for information loss during black hole evaporation: (i) a pure state evolves to a mixed state and (ii) the map from the initial state to final state is non-invertible. Any proposed resolution of the information paradox must address both these issues. The firewall argument focuses only on the first and this leads to order one deviations from the Unruh vacuum for maximally entangled black holes. The nature of the argument does not extend to black holes in pure states. It was shown by Avery, Puhm and the author that requiring the initial state to final state map to be invertible mandates structure at the horizon even for pure states. The proof works if black holes can be formed in generic states and in this paper we show that this is indeed the case. We also demonstrate how models proposed by Susskind, Papadodimas et al. and Maldacena et al. end up making the initial to final state map non-invertible and thus make the horizon "cool" at the cost of unitarity.

THE EVENT HORIZON OF SAGITTARIUS A*

International Nuclear Information System (INIS)

Broderick, Avery E.; Loeb, Abraham; Narayan, Ramesh

2009-01-01

Black hole event horizons, causally separating the external universe from compact regions of spacetime, are one of the most exotic predictions of general relativity. Until recently, their compact size has prevented efforts to study them directly. Here we show that recent millimeter and infrared observations of Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way, all but require the existence of a horizon. Specifically, we show that these observations limit the luminosity of any putative visible compact emitting region to below 0.4% of Sgr A*'s accretion luminosity. Equivalently, this requires the efficiency of converting the gravitational binding energy liberated during accretion into radiation and kinetic outflows to be greater than 99.6%, considerably larger than those implicated in Sgr A*, and therefore inconsistent with the existence of such a visible region. Finally, since we are able to frame this argument entirely in terms of observable quantities, our results apply to all geometric theories of gravity that admit stationary solutions, including the commonly discussed f(R) class of theories.

THE EVENT HORIZON OF SAGITTARIUS A*

Energy Technology Data Exchange (ETDEWEB)

Broderick, Avery E [Canadian Institute for Theoretical Astrophysics, 60 St. George St., Toronto, ON M5S 3H8 (Canada); Loeb, Abraham; Narayan, Ramesh [Institute for Theory and Computation, Harvard University, Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)

2009-08-20

Black hole event horizons, causally separating the external universe from compact regions of spacetime, are one of the most exotic predictions of general relativity. Until recently, their compact size has prevented efforts to study them directly. Here we show that recent millimeter and infrared observations of Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way, all but require the existence of a horizon. Specifically, we show that these observations limit the luminosity of any putative visible compact emitting region to below 0.4% of Sgr A*'s accretion luminosity. Equivalently, this requires the efficiency of converting the gravitational binding energy liberated during accretion into radiation and kinetic outflows to be greater than 99.6%, considerably larger than those implicated in Sgr A*, and therefore inconsistent with the existence of such a visible region. Finally, since we are able to frame this argument entirely in terms of observable quantities, our results apply to all geometric theories of gravity that admit stationary solutions, including the commonly discussed f(R) class of theories.

Recollections of Jack Michael and the Application of Skinner's Analysis of Verbal Behavior

Science.gov (United States)

Sundberg, Mark L.

2017-01-01

Jack Michael offered a course on verbal behavior almost every year throughout his teaching career. Jack was also interested in the application of Skinner's work and in 1976 began to offer a graduate course at Western Michigan University titled Verbal Behavior Applications. Jack and his students pursued the application of Skinner's work on verbal…

Smooth horizons and quantum ripples

Energy Technology Data Exchange (ETDEWEB)

Golovnev, Alexey [Saint Petersburg State University, High Energy Physics Department, Saint-Petersburg (Russian Federation)

2015-05-15

Black holes are unique objects which allow for meaningful theoretical studies of strong gravity and even quantum gravity effects. An infalling and a distant observer would have very different views on the structure of the world. However, a careful analysis has shown that it entails no genuine contradictions for physics, and the paradigm of observer complementarity has been coined. Recently this picture was put into doubt. In particular, it was argued that in old black holes a firewall must form in order to protect the basic principles of quantum mechanics. This AMPS paradox has already been discussed in a vast number of papers with different attitudes and conclusions. Here we want to argue that a possible source of confusion is the neglect of quantum gravity effects. Contrary to widespread perception, it does not necessarily mean that effective field theory is inapplicable in rather smooth neighbourhoods of large black hole horizons. The real offender might be an attempt to consistently use it over the huge distances from the near-horizon zone of old black holes to the early radiation. We give simple estimates to support this viewpoint and show how the Page time and (somewhat more speculative) scrambling time do appear. (orig.)

Smooth horizons and quantum ripples

International Nuclear Information System (INIS)

Golovnev, Alexey

2015-01-01

Black holes are unique objects which allow for meaningful theoretical studies of strong gravity and even quantum gravity effects. An infalling and a distant observer would have very different views on the structure of the world. However, a careful analysis has shown that it entails no genuine contradictions for physics, and the paradigm of observer complementarity has been coined. Recently this picture was put into doubt. In particular, it was argued that in old black holes a firewall must form in order to protect the basic principles of quantum mechanics. This AMPS paradox has already been discussed in a vast number of papers with different attitudes and conclusions. Here we want to argue that a possible source of confusion is the neglect of quantum gravity effects. Contrary to widespread perception, it does not necessarily mean that effective field theory is inapplicable in rather smooth neighbourhoods of large black hole horizons. The real offender might be an attempt to consistently use it over the huge distances from the near-horizon zone of old black holes to the early radiation. We give simple estimates to support this viewpoint and show how the Page time and (somewhat more speculative) scrambling time do appear. (orig.)

Invited Commentary: Continuing to Loosen the Constraints on Epidemiology in an Age of Change-A Comment on McMichael's "Prisoners of the Proximate".

Science.gov (United States)

Galea, Sandro

2017-06-01

Published in 1999, McMichael's "Prisoners of the Proximate: Loosening the Constraints on Epidemiology in an Age of Change" (Am J Epidemiol. 1999;149(10):887-897) outlined an exciting vision for epidemiology as the field that that can help us better understand the drivers of population health so that we may intervene, paving the way for healthier populations. McMichael's paper remains today what it was when it was first published: clear, thoughtful, provocative, and usefully prescriptive in its call to action. McMichael identified 4 constraints facing epidemiology. The field has risen to this challenge and addressed some of these constraints. I discuss how successful (or not) we have been in addressing each of these 4 challenges. © The Author 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Le Falstaff de Manfredo Maggioni et Michael Balfe : façonner un opéra italien pour le public anglais Adapting The Merry Wives of Windsor for the Italian Stage: Falstaff by Manfredo Maggioni and Michael Balfe

Directory of Open Access Journals (Sweden)

Céline Frigau

2011-12-01

Full Text Available Le Falstaff de Manfredo Maggioni et Michael Balfe constitue un cas à la fois exemplaire et unique de réécriture lyrique d’une œuvre de Shakespeare. Inspiré des Merry Wives of Windsor, l’opera buffa est écrit en 1838 pour le public de l’opéra italien de Londres, par un librettiste italien et un compositeur irlandais – une première dans un théâtre où l’on ne passe commande qu’auprès de maestri italiens. Des efforts de Maggioni et de Balfe résulte un véritable opéra italien qui respecte les codes structurels, les pratiques vocales et scéniques qui le rendent reconnaissable comme opera buffa sur la scène esthétique du temps. La question de la réécriture engage ici la réflexion sur les processus intimement liés de production et de réception précis, comme sur l’horizon d’attente du public londonien pour circonscrire les frontières d’une catégorie esthétique nommée « opéra italien » qui se définit aussi et peut-être avant tout loin de la péninsule, au contact de spectateurs non italophones, au fil d’échanges à l’échelle européenne.Based on Shakespeare’s Merry Wives of Windsor, Michael Balfe’s Falstaff, created in 1838 for London’s Italian opera audiences, was the work of an Italian librettist, Manfredo Maggioni, and an Irish composer, a first in a theatre where only Italian maestri were commissioned for new works. Balfe’s and Maggioni’s combined efforts resulted in a truly genuine Italian opera buffa. Not only is it sung in Italian but it also respects the structural codes, vocal and scenic practices which make it recognizable as an opera buffa on the aesthetic stage of the time, and above all on the English stage. The issue of rewriting implies here a reflection on the intimately linked processes of production and reception. Through the study of the libretto and score, its contextualization, as well as contemporary accounts, we will be concerned both with questioning the

New perspectives for European climate services: HORIZON2020

Science.gov (United States)

Bruning, Claus; Tilche, Andrea

2014-05-01

The developing of new end-to-end climate services was one of the core priorities of 7th Framework for Research and Technological Development of the European Commission and will become one of the key strategic priorities of Societal Challenge 5 of HORIZON2020 (the new EU Framework Programme for Research and Innovation 2014-2020). Results should increase the competitiveness of European businesses, and the ability of regional and national authorities to make effective decisions in climate-sensitive sectors. In parallel, the production of new tailored climate information should strengthen the resilience of the European society to climate change. In this perspective the strategy to support and foster the underpinning science for climate services in HORIZON2020 will be presented.

Pricing Liquidity Risk with Heterogeneous Investment Horizons

NARCIS (Netherlands)

Beber, A.; Driessen, J.; Tuijp, P.F.A.

2012-01-01

We develop a new asset pricing model with stochastic transaction costs and investors with heterogenous horizons. Short-term investors hold only liquid assets in equilibrium. This generates segmentation effects in the pricing of liquid versus illiquid assets. Specifically, the liquidity (risk) premia

Rogue events in the group velocity horizon.

Science.gov (United States)

Demircan, Ayhan; Amiranashvili, Shalva; Brée, Carsten; Mahnke, Christoph; Mitschke, Fedor; Steinmeyer, Günter

2012-01-01

The concept of rogue waves arises from a mysterious and potentially calamitous phenomenon of oceanic surfaces. There is mounting evidence that they are actually commonplace in a variety of different physical settings. A set of defining criteria has been advanced; this set is of great generality and therefore applicable to a wide class of systems. The question arises naturally whether there are generic mechanisms responsible for extreme events in different systems. Here we argue that under suitable circumstances nonlinear interaction between weak and strong waves results in intermittent giant waves with all the signatures of rogue waves. To obtain these circumstances only a few basic conditions must be met. Then reflection of waves at the so-called group-velocity horizon occurs. The connection between rogue waves and event horizons, seemingly unrelated physical phenomena, is identified as a feature common in many different physical systems.

No-horizon theorem for spacetimes with spacelike G{sub 1} isometry groups

Energy Technology Data Exchange (ETDEWEB)

Goncalves, Sergio M C V [Department of Physics, Yale University, New Haven, CT 06511 (United States)

2003-12-21

We consider four-dimensional spacetimes (M, g) which obey the Einstein equations G = T and admit a global spacelike G{sub 1} = R isometry group. By means of dimensional reduction and local analysis on the reduced (2 + 1) spacetime, we obtain a sufficient condition on T which guarantees that (M, g) cannot contain apparent horizons. Given any (3 + 1) spacetime with spacelike translational isometry, the no-horizon condition can be readily tested without the need for dimensional reduction. This provides thus a useful and encompassing apparent horizon test for G{sub 1}-symmetric spacetimes. We argue that this adds further evidence towards the validity of the hoop conjecture and signals possible (albeit arguably unlikely) violations of strong cosmic censorship.

The works of Joseph and Michael Haydn in Ondřej Horník's collection

Czech Academy of Sciences Publication Activity Database

Freemanová, Michaela

2017-01-01

Roč. 9, 1-2 (2017), s. 14-23 ISSN 1803-7828 Institutional support: RVO:68378076 Keywords : music manuscripts * Joseph Haydn * Michael Haydn * Ondřej Horník's collection * church music Subject RIV: AL - Art, Architecture, Cultural Heritage OBOR OECD: Performing arts studies ( Music ology, Theater science, Dramaturgy) http://www.nm.cz/publikace/archiv.php?id=16

Ancient DNA Analysis Suggests Negligible Impact of the Wari Empire Expansion in Peru's Central Coast during the Middle Horizon.

Science.gov (United States)

Valverde, Guido; Barreto Romero, María Inés; Flores Espinoza, Isabel; Cooper, Alan; Fehren-Schmitz, Lars; Llamas, Bastien; Haak, Wolfgang

2016-01-01

The analysis of ancient human DNA from South America allows the exploration of pre-Columbian population history through time and to directly test hypotheses about cultural and demographic evolution. The Middle Horizon (650-1100 AD) represents a major transitional period in the Central Andes, which is associated with the development and expansion of ancient Andean empires such as Wari and Tiwanaku. These empires facilitated a series of interregional interactions and socio-political changes, which likely played an important role in shaping the region's demographic and cultural profiles. We analyzed individuals from three successive pre-Columbian cultures present at the Huaca Pucllana archaeological site in Lima, Peru: Lima (Early Intermediate Period, 500-700 AD), Wari (Middle Horizon, 800-1000 AD) and Ychsma (Late Intermediate Period, 1000-1450 AD). We sequenced 34 complete mitochondrial genomes to investigate the potential genetic impact of the Wari Empire in the Central Coast of Peru. The results indicate that genetic diversity shifted only slightly through time, ruling out a complete population discontinuity or replacement driven by the Wari imperialist hegemony, at least in the region around present-day Lima. However, we caution that the very subtle genetic contribution of Wari imperialism at the particular Huaca Pucllana archaeological site might not be representative for the entire Wari territory in the Peruvian Central Coast.

Ancient DNA Analysis Suggests Negligible Impact of the Wari Empire Expansion in Peru's Central Coast during the Middle Horizon.

Directory of Open Access Journals (Sweden)

Guido Valverde

Full Text Available The analysis of ancient human DNA from South America allows the exploration of pre-Columbian population history through time and to directly test hypotheses about cultural and demographic evolution. The Middle Horizon (650-1100 AD represents a major transitional period in the Central Andes, which is associated with the development and expansion of ancient Andean empires such as Wari and Tiwanaku. These empires facilitated a series of interregional interactions and socio-political changes, which likely played an important role in shaping the region's demographic and cultural profiles. We analyzed individuals from three successive pre-Columbian cultures present at the Huaca Pucllana archaeological site in Lima, Peru: Lima (Early Intermediate Period, 500-700 AD, Wari (Middle Horizon, 800-1000 AD and Ychsma (Late Intermediate Period, 1000-1450 AD. We sequenced 34 complete mitochondrial genomes to investigate the potential genetic impact of the Wari Empire in the Central Coast of Peru. The results indicate that genetic diversity shifted only slightly through time, ruling out a complete population discontinuity or replacement driven by the Wari imperialist hegemony, at least in the region around present-day Lima. However, we caution that the very subtle genetic contribution of Wari imperialism at the particular Huaca Pucllana archaeological site might not be representative for the entire Wari territory in the Peruvian Central Coast.

Information loss problem and a ‘black hole’ model with a closed apparent horizon

International Nuclear Information System (INIS)

Frolov, Valeri P.

2014-01-01

In a classical description the spacetime curvature inside a black hole infinitely grows. In the domain where it reaches the Planckian value and exceeds it the Einstein equations should be modified. In the absence of reliable theory of quantum gravity it is instructive to consider simplified models. We assume that a spacetime curvature is limited by some value (of the order of the Planckian one). We use modified Vaidya metric, proposed by Hayward, to describe the black hole evaporation process. In such a spacetime the curvature near r=0 remains finite, it does not have an event horizon and its apparent horizon is closed. If the initial mass of such a ‘black hole’ is much larger than the Planckian one its properties (as seen by an external observer) are practically the same as properties of the ‘standard’ black hole with the event horizon. We study outgoing null rays in the vicinity of the outer apparent horizon and introduce a notion of a quasi-horizon. We demonstrate that particles, trapped inside a ‘black hole’ during the evaporation process, finally may return to external space after the evaporation is completed. We also demonstrate that such quanta would have very large blue-shift. The absence of the event horizon makes it possible restoration of the unitarity in evaporating black holes

Anomalous current in periodic Lorentz gases with infinite horizon

Energy Technology Data Exchange (ETDEWEB)

Dolgopyat, Dmitrii I [University of Maryland, College Park (United States); Chernov, Nikolai I [University of Alabama at Birmingham, Birmingham, Alabama (United States)

2009-08-31

Electric current is studied in a two-dimensional periodic Lorentz gas in the presence of a weak homogeneous electric field. When the horizon is finite, that is, free flights between collisions are bounded, the resulting current J is proportional to the voltage difference E, that is, J=1/2 D*E+o(||E||), where D* is the diffusion matrix of a Lorentz particle moving freely without an electric field (see a mathematical proof). This formula agrees with Ohm's classical law and the Einstein relation. Here the more difficult model with an infinite horizon is investigated. It is found that infinite corridors between scatterers allow the particles (electrons) to move faster, resulting in an abnormal current (causing 'superconductivity'). More precisely, the current is now given by J=1/2 DE| log||E|| | + O(||E||), where D is the 'superdiffusion' matrix of a Lorentz particle moving freely without an electric field. This means that Ohm's law fails in this regime, but the Einstein relation (suitably interpreted) still holds. New results are also obtained for the infinite-horizon Lorentz gas without external fields, complementing recent studies by Szasz and Varju. Bibliography: 31 titles.

Anomalous current in periodic Lorentz gases with infinite horizon

International Nuclear Information System (INIS)

Dolgopyat, Dmitrii I; Chernov, Nikolai I

2009-01-01

Electric current is studied in a two-dimensional periodic Lorentz gas in the presence of a weak homogeneous electric field. When the horizon is finite, that is, free flights between collisions are bounded, the resulting current J is proportional to the voltage difference E, that is, J=1/2 D*E+o(||E||), where D* is the diffusion matrix of a Lorentz particle moving freely without an electric field (see a mathematical proof). This formula agrees with Ohm's classical law and the Einstein relation. Here the more difficult model with an infinite horizon is investigated. It is found that infinite corridors between scatterers allow the particles (electrons) to move faster, resulting in an abnormal current (causing 'superconductivity'). More precisely, the current is now given by J=1/2 DE| log||E|| | + O(||E||), where D is the 'superdiffusion' matrix of a Lorentz particle moving freely without an electric field. This means that Ohm's law fails in this regime, but the Einstein relation (suitably interpreted) still holds. New results are also obtained for the infinite-horizon Lorentz gas without external fields, complementing recent studies by Szasz and Varju. Bibliography: 31 titles.

Identifying Disruptive Technologies in Design: Horizon Scanning in the Early Stages of Design

DEFF Research Database (Denmark)

Ernstsen, Sidsel Katrine; Thuesen, Christian; Larsen, Laurids Rolighed

context to anticipate disruption of construction. By means of a 3-step horizon scan, we identify 133 potentially disruptive technologies from across industries. We find that when preparing for disruption, design may benefit from the future-oriented and technology-focused features of horizon scanning....

Effects of pipeline construction on chernozemic and solonetzic A and B horizons in Central Alberta

Energy Technology Data Exchange (ETDEWEB)

Landsburg, S. (NOVA Corp. of Alberta, Calgary, AB (Canada))

1989-05-01

The effects of pipeline construction on agricultural soil quality ratings were evaluated for the A and B horizons of Orthic Dark Brown Chernozem and Dark Brown Solonetz soils at three sites in Central Alberta 1 wk after construction. At each site, samples of the Ap horizon from the spoil side, trench, and work side portions of a pipeline right-of-way were compared to a sample of the Ap horizon from an adjacent area unaffected by pipeline construction. Spoil material below replaced topsoil on the trench was compared to a sample of an undisturbed B horizon. Regardless of soil type or land use, construction had no effect on the Ap horizon on the work side. This was due to optimum weather conditions during construction; low rainfall resulted in lack of soil ruting and minimal soil mixing. For both soil types under cultivation, construction increased soluble salt concentrations in the Ap horizons on the spoil side due to mixing of topsoil and spoil materials. There were few effects on the Ap horizon on the spoil side in pasture land, due to trench only topsoil stripping and easy spoil removal from a well-developed sod layer. Both the Ap and spoil from the trench in the Dark Brown Solonetz had increased salt concentrations, while there were few changes in the Dark Brown Chernozem. Mixing of topsoil and spoil material, and bringing salt-enriched material to the spoil surface are thought to be reponsible for the effects due to construction were reflected in the Ap horizon of the trench and spoil side by changes in pH, electrical conductivity, soluble salts and bulk density. Even with the increases in the soil properties monitored, the results indicated that regardless of soil type or land use, pipeline construction did not significantly affect the agricultural soil quality of the A and B horizons. 12 refs., 3 figs., 2 tabs.

Short-horizon regulation for long-term investors

NARCIS (Netherlands)

Shi, Z.; Werker, B.J.M.

2012-01-01

We study the effects of imposing repeated short-horizon regulatory constraints on long-term investors. We show that Value-at-Risk and Expected Shortfall constraints, when imposed dynamically, lead to similar optimal portfolios and wealth distributions. We also show that, in utility terms, the costs

Asymptotic symmetries on the Kerr-Newman horizon without the anomaly of diffeomorphism invariance

International Nuclear Information System (INIS)

Koga, Jun-ichirou

2008-01-01

We analyze asymptotic symmetries on the Killing horizon of the four-dimensional Kerr-Newman black hole. We first derive the asymptotic Killing vectors on the Killing horizon, which describe the asymptotic symmetries, and find that the general form of these asymptotic Killing vectors is the universal one possessed by arbitrary Killing horizons. We then construct the phase space associated with the asymptotic symmetries. It is shown that the phase space of an extreme black hole either has the size comparable with a non-extreme black hole, or is small enough to exclude degeneracy, depending on whether or not the global structure of a Killing horizon particular to an extreme black hole is respected. We also show that the classical central charge in the Poisson brackets algebra of these asymptotic symmetries vanishes, which implies that there is not an anomaly of diffeomorphism invariance. By taking into account other results in the literature, we argue that the vanishing central charge on a black hole horizon, in an effective theory, looks consistent with the thermal feature of a black hole. We furthermore argue that the vanishing central charge implies that there are sufficiently many classical configurations that constitute a single macroscopic state, while these configurations are distinguished physically

Numerical Tests of the Cosmic Censorship Conjecture via Event-Horizon Finding

Science.gov (United States)

Okounkova, Maria; Ott, Christian; Scheel, Mark; Szilagyi, Bela

2015-04-01

We present the current state of our research on the possibility of naked singularity formation in gravitational collapse, numerically testing both the cosmic censorship conjecture and the hoop conjecture. The former of these posits that all singularities lie behind an event horizon, while the later conjectures that this is true if collapse occurs from an initial configuration with all circumferences C <= 4 πM . We reconsider the classical Shapiro & Teukolsky (1991) prolate spheroid naked singularity scenario. Using the exponentially error-convergent Spectral Einstein Code (SpEC) we simulate the collapse of collisionless matter and probe for apparent horizons. We propose a new method to probe for the existence of an event horizon by following characteristic from regions near the singularity, using methods commonly employed in Cauchy characteristic extraction. This research was partially supported by NSF under Award No. PHY-1404569.

Progress in ultrasonic spray pyrolysis for condensed matter sciences developed from ultrasonic nebulization theories since Michael Faraday

CSIR Research Space (South Africa)

Mwakikunga, BW

2014-01-01

Full Text Available This review outlines, in great detail, the history of the phenomenon of ultrasonic nebulization of liquids since the discovery of such an effect by Michael Faraday and the explanation of the phenomenon by capillary wave mechanism and “cavitation...

Joint horizon scanning: identifying common strategic choices and questions for knowledge

OpenAIRE

Victor van Rij

2010-01-01

Over the past decade, horizon scanning has been recognised as part of forward-looking government processes in a number of industrialised countries. It helps policy-makers in addressing the diversity of future societal and environmental challenges and in addressing the potential of emerging areas of science and technology in an integrated way. This paper discusses the usefulness of horizon scanning as an additional tool for future-oriented technology analysis activities, such as technology for...

A facile and efficient method of enzyme immobilization on silica particles via Michael acceptor film coatings: immobilized catalase in a plug flow reactor.

Science.gov (United States)

Bayramoglu, Gulay; Arica, M Yakup; Genc, Aysenur; Ozalp, V Cengiz; Ince, Ahmet; Bicak, Niyazi

2016-06-01

A novel method was developed for facile immobilization of enzymes on silica surfaces. Herein, we describe a single-step strategy for generating of reactive double bonds capable of Michael addition on the surfaces of silica particles. This method was based on reactive thin film generation on the surfaces by heating of impregnated self-curable polymer, alpha-morpholine substituted poly(vinyl methyl ketone) p(VMK). The generated double bonds were demonstrated to be an efficient way for rapid incorporation of enzymes via Michael addition. Catalase was used as model enzyme in order to test the effect of immobilization methodology by the reactive film surface through Michael addition reaction. Finally, a plug flow type immobilized enzyme reactor was employed to estimate decomposition rate of hydrogen peroxide. The highly stable enzyme reactor could operate continuously for 120 h at 30 °C with only a loss of about 36 % of its initial activity.

Enantioselective organocatalyzed Oxa-Michael-Aldol cascade reactions: Construction of chiral 4H-chromenes with a trifluoromethylated tetrasubstituted carbon stereocenter

KAUST Repository

Zhang, Jing; Ajitha, Manjaly John; He, Lin; Liu, Kai; Dai, Bin; Huang, Kuo-Wei

2015-01-01

The first organocatalytic asymmetric synthesis of 4H-chromenes bearing a trifluoromethylated tetrasubstituted carbon center is presented. Chiral secondary amines promote the oxa-Michael-aldol cascade reaction between alkynals and 2

Why There Are Certain Parallels Between Joachim C. Fest’s Hitler-Biography and Michael Wolff’s Trump-Book

Directory of Open Access Journals (Sweden)

Christian Fuchs

2018-02-01

Full Text Available Joachim C. Fest published one of the most widely read Hitler biographies in 1973. Are there parallels of its analytical approach to Michael Wolff’s “Fire and Fury: Inside the Trump White House”?

Michael T. Westrate. Living Soviet in Ukraine from Stalin to Maidan: Under the Falling Red Star in Kharkiv.

Directory of Open Access Journals (Sweden)

Charitie V. Hyman

2017-09-01

Full Text Available Book review of Michael T. Westrate. Living Soviet in Ukraine from Stalin to Maidan: Under the Falling Red Star in Kharkiv. Rowman & Littlefield, 2016. xx, 232 pp. Illustrations. Appendices. Bibliography. Index. $85.00, cloth.

Pedogenetic processes in anthrosols with pretic horizon (Amazonian Dark Earth in Central Amazon, Brazil.

Directory of Open Access Journals (Sweden)

Rodrigo S Macedo

Full Text Available Anthrosols known as Amazonian Dark Earth (ADE have borne witness to the intensification of sedentary patterns and the demographic increase in Central Amazon. As a result, a recurring pattern has been observed of mounds with ADE arising from domestic activities and the disposal of waste. The objective of this research was to demonstrate the relationship of these anthropic activities with pedogenetic formation processes of ADE in the municipality of Iranduba, Brazil. Disturbed and undisturbed soil samples were taken from two areas of ADE (pretic horizon and from a non-anthropic pedon. Physical, chemical, micromorphological and SEM-EDS analyses were performed. The coarse material of the pretic horizons consisted predominantly of quartz, iron nodules, ceramics and charcoal fragments, and the fine material is organo-mineral. There was a direct relationship between the color of pretic horizons and the number of charcoal fragments. The thickness of the ADE results from the redistribution of charcoal at depth through bioturbation, transforming subsurface horizons into anthropic horizons. ADE presents granular microaggregates of geochemical and zoogenetic origin. Degradation of iron nodules is intensified in pretic horizons, promoting a reverse pedogenic process contributing to the xanthization process. Surprisingly the anthropic activities also favor clay dispersion and argilluviation; clay coatings on the ceramic fragments and in the pores demonstrate that this is a current process. Processes identified as contributing to ADE genesis included: i addition of organic residues and ceramic artifacts (cumulization with the use of fire; ii mechanical action of humans, roots and macrofauna (bioturbation; iii melanization of deeper horizons as a result of bioturbation; iv argilluviation and degradation of iron nodules. This study offers new support to archaeological research in respect to ADE formation processes in Central Amazon and confirmed the hypothesis

Inner cauchy horizon of axisymmetric and stationary black holes with surrounding matter in einstein-maxwell theory.

Science.gov (United States)

Ansorg, Marcus; Hennig, Jörg

2009-06-05

We study the interior electrovacuum region of axisymmetric and stationary black holes with surrounding matter and find that there exists always a regular inner Cauchy horizon inside the black hole, provided the angular momentum J and charge Q of the black hole do not vanish simultaneously. In particular, we derive an explicit relation for the metric on the Cauchy horizon in terms of that on the event horizon. Moreover, our analysis reveals the remarkable universal relation (8piJ);{2}+(4piQ;{2});{2}=A;{+}A;{-}, where A+ and A- denote the areas of event and Cauchy horizon, respectively.

Jack Michael's Musings on the 60th Anniversary of Skinner's "Verbal Behavior"

Science.gov (United States)

Esch, Barbara E.; Esch, John W.; Palmer, David C.

2017-01-01

When the B. F. Skinner Foundation reprinted Skinner's "Verbal Behavior" in 1992, Jack Michael wrote one of its two forewords, a detailed outline of the book's purpose and scope. On the 60th anniversary of the first publication (1957) of "Verbal Behavior", Jack reflects on the book's impact and its importance to the…

Asymmetric organocatalytic Michael addition of Meldrum's acid to nitroalkenes: probing the mechanism of bifunctional thiourea organocatalysts

OpenAIRE

Kataja, Antti O.; Koskinen, Ari M.P.

2010-01-01

The asymmetric Michael addition of Meldrum’s acid to nitroalkenes was studied using a novel type of Cinchona alkaloid-based bifunctional thiourea organocatalyst. The functionality of the thiourea catalysts was also probed by preparing and testing thiourea-N-methylated analogues of the well-known bis-(3,5-trifluoromethyl)phenyl-substituted catalyst. Peer reviewed

Vision and Elusiveness in Philosophy of Education: R. S. Peters on the Legacy of Michael Oakeshott

Science.gov (United States)

Williams, Kevin

2009-01-01

Despite his elusiveness on important issues, there is much in Michael Oakeshott's educational vision that Richard Peters quite rightly wishes to endorse. The main aim of this essay is, however, to consider Peters' justifiable critique of three features of Oakeshott's work. These are (1) the rigidity of his distinction between vocational and…

The effect of sources on horizons that may develop when plane gravitational waves collide

International Nuclear Information System (INIS)

Chandrasekhar, Subrahmanyan; Xanthopoulos, B.C.

1987-01-01

Colliding plane gravitational waves that lead to the development of a horizon and a subsequent time-like singularity are coupled with an electromagnetic field, a perfect fluid, and null dust (consisting of massless particles). The coupling of the gravitational waves with an electromagnetic field does not affect, in any essential way, the development of the horizon or the time-like singularity if the polarizations of the colliding gravitational waves are not parallel. If the polarizations are parallel, the space-like singularity which occurs in the vacuum is transformed into a horizon followed by a three-dimensional time-like singularity by the merest presence of the electromagnetic field. The coupling of the gravitational waves with a perfect fluid and null dust affect the development of horizons and singularities in radically different ways: the perfect fluid affects the development decisively in all cases but qualitatively in the same way, while null dust prevents the development of horizons and allows only the development of space-like singularities. The contrasting behaviours of a perfect fluid and of null dust in the framework of general relativity is compared with the behaviours one may expect, under similar circumstances, in the framework of special relativity. (author)

RNA-Seq reveals complex genetic response to deepwater horizon oil release in Fundulus grandis

Directory of Open Access Journals (Sweden)

Garcia Tzintzuni I

2012-09-01

Full Text Available Abstract Background The release of oil resulting from the blowout of the Deepwater Horizon (DH drilling platform was one of the largest in history discharging more than 189 million gallons of oil and subject to widespread application of oil dispersants. This event impacted a wide range of ecological habitats with a complex mix of pollutants whose biological impact is still not yet fully understood. To better understand the effects on a vertebrate genome, we studied gene expression in the salt marsh minnow Fundulus grandis, which is local to the northern coast of the Gulf of Mexico and is a sister species of the ecotoxicological model Fundulus heteroclitus. To assess genomic changes, we quantified mRNA expression using high throughput sequencing technologies (RNA-Seq in F. grandis populations in the marshes and estuaries impacted by DH oil release. This application of RNA-Seq to a non-model, wild, and ecologically significant organism is an important evaluation of the technology to quickly assess similar events in the future. Results Our de novo assembly of RNA-Seq data produced a large set of sequences which included many duplicates and fragments. In many cases several of these could be associated with a common reference sequence using blast to query a reference database. This reduced the set of significant genes to 1,070 down-regulated and 1,251 up-regulated genes. These genes indicate a broad and complex genomic response to DH oil exposure including the expected AHR-mediated response and CYP genes. In addition a response to hypoxic conditions and an immune response are also indicated. Several genes in the choriogenin family were down-regulated in the exposed group; a response that is consistent with AH exposure. These analyses are in agreement with oligonucleotide-based microarray analyses, and describe only a subset of significant genes with aberrant regulation in the exposed set. Conclusion RNA-Seq may be successfully applied to feral and

Is the Gravitational-Wave Ringdown a Probe of the Event Horizon?

Science.gov (United States)

Cardoso, Vitor; Franzin, Edgardo; Pani, Paolo

2016-04-29

It is commonly believed that the ringdown signal from a binary coalescence provides a conclusive proof for the formation of an event horizon after the merger. This expectation is based on the assumption that the ringdown waveform at intermediate times is dominated by the quasinormal modes of the final object. We point out that this assumption should be taken with great care, and that very compact objects with a light ring will display a similar ringdown stage, even when their quasinormal-mode spectrum is completely different from that of a black hole. In other words, universal ringdown waveforms indicate the presence of light rings, rather than of horizons. Only precision observations of the late-time ringdown signal, where the differences in the quasinormal-mode spectrum eventually show up, can be used to rule out exotic alternatives to black holes and to test quantum effects at the horizon scale.

A Receding Horizon Controller for the Steam Generator Water Level

International Nuclear Information System (INIS)

Na, Man Gyun; Lee, Yoon Joon

2003-01-01

In this work, the receding horizon control method was used to control the water level of nuclear steam generators and applied to two linear models and also a nonlinear model of steam generators. A receding horizon control method is to solve an optimization problem for finite future steps at current time and to implement the first optimal control input as the current control input. The procedure is then repeated at each subsequent instant. The dynamics of steam generators is very different according to power levels. The receding horizon controller is designed by using a reduced linear steam generator model fixed over a certain power range and applied to a Westinghouse-type (U-tube recirculating type) nuclear steam generator. The proposed controller designed at a fixed power level shows good performance for any other power level within this power range. The steam generator shows actually nonlinear characteristics. Therefore, the proposed algorithm is implemented for a nonlinear model of the nuclear steam generator to verify its real performance and also shows good responses

Air Sampling Data for BP Spill/Deepwater Horizon

Data.gov (United States)

U.S. Environmental Protection Agency — The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following...

Waste Sampling Data for BP Spill/Deepwater Horizon

Data.gov (United States)

U.S. Environmental Protection Agency — The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following...

Air Monitoring Data for BP Spill/Deepwater Horizon

Data.gov (United States)

U.S. Environmental Protection Agency — The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following...

Water Sampling Data for BP Spill/Deepwater Horizon

Data.gov (United States)

U.S. Environmental Protection Agency — The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following...

Sediment Sampling Data for BP Spill/Deepwater Horizon

Data.gov (United States)

U.S. Environmental Protection Agency — The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following...

Sighting Horizons of Teaching in Higher Education

Science.gov (United States)

Barnett, Ronald; Guzmán-Valenzuela, Carolina

2017-01-01

This conceptual paper tackles the matter of teaching in higher education and proposes a concept of "horizons of teaching." It firstly offers an overview of the considerable empirical literature around teaching--especially conceptions of teaching, approaches to teaching and teaching practices--and goes on to pose some philosophical and…

The NMC Horizon Report: 2013 Museum Edition

Science.gov (United States)

Johnson, L.; Adams Becker, S.; Freeman, A.

2013-01-01

The "NMC Horizon Report: 2013 Museum Edition," is a co-production with the Marcus Institute for Digital Education in the Arts (MIDEA), and examines six emerging technologies for their potential impact on and use in education and interpretation within the museum environment: BYOD (Bring Your Own Device), crowdsourcing, electronic…

Rolling-horizon replenishment : Policies and performance analysis

NARCIS (Netherlands)

Lian, Z.; Liu, L.; Zhu, Stuart X.

We consider a rolling-horizon (RH) replenishment modeling framework under which a buyer can update demand information and inventory status, modify order quantities committed previously, place an advanced order for a new period at the end of the RH, and move along in time seamlessly. We show that the

Hexamethoxylated Monocarbonyl Analogues of Curcumin Cause G2/M Cell Cycle Arrest in NCI-H460 Cells via Michael Acceptor-Dependent Redox Intervention.

Science.gov (United States)

Li, Yan; Zhang, Li-Ping; Dai, Fang; Yan, Wen-Jing; Wang, Hai-Bo; Tu, Zhi-Shan; Zhou, Bo

2015-09-09

Curcumin, derived from the dietary spice turmeric, holds promise for cancer prevention. This prompts much interest in investigating the action mechanisms of curcumin and its analogues. Two symmetrical hexamethoxy-diarylpentadienones (1 and 2) as cucumin analogues were reported to possess significantly enhanced cytotoxicity compared with the parent molecule. However, the detailed mechanisms remain unclear. In this study, compounds 1 and 2 were identified as the G2/M cell cycle arrest agents to mediate the cytotoxicity toward NCI-H460 cells via Michael acceptor-dependent redox intervention. Compared with curcumin, they could more easily induce a burst of reactive oxygen species (ROS) and collapse of the redox buffering system. One possible reason is that they could more effectively target intracellular TrxR to convert this antioxidant enzyme into a ROS promoter. Additionally, they caused up-regulation of p53 and p21 and down-regulation of redox-sensitive Cdc25C along with cyclin B1/Cdk1 in a Michael acceptor- and ROS-dependent fashion. Interestingly, in comparison with compound 2, compound 1 displayed a relatively weak ability to generate ROS but increased cell cycle arrest activity and cytotoxicity probably due to its Michael acceptor-dependent microtubule-destabilizing effect and greater GST-inhibitory activity, as well as its enhanced cellular uptake. This work provides useful information for understanding Michael acceptor-dependent and redox-mediated cytotoxic mechanisms of curcumin and its active analogues.

A theory of planning horizons (1: market design in a post-neoclassical world

Directory of Open Access Journals (Sweden)

Frederic B. Jennings, Jr.

2012-05-01

Full Text Available The neoclassical case supporting competitive frames and market solutions has failed to promote stable world-wide economic development. Other approaches in economics incorporate social culture, increasing returns, market power, ecological limits and complementarity, yielding broader applications for development theory. In this paper a theory of planning horizons is introduced to raise some meaningful questions about the traditional view with respect to its substitution, decreasing returns and independence assumptions. Suppositions of complementarity, increasing returns and interdependence suggest that competition is inefficient by upholding a myopic culture resistant to learning. Growth – though long believed to rise from markets and competitive values – may not derive from these sources. Instead, as civilizations advance, shifting from material wants to higher-order intangible output, they evolve from market tradeoffs (substitution and scarcity into realms of common need (complementarity and abundance. The policy implications of horizonal theory are explored, with respect to regulatory aims and economic concerns. Such an approach emphasizes strict constraints against entry barriers, ecological harm, market power abuse and ethical lapses. Social cohesion – not competition – is sought as a means to extend horizons and thereby increase efficiency, equity and ecological health. The overriding importance of horizon effects for regulatory assessment dominates other orthodox standards in economics and law. Reframing economics along horizonal lines suggests some meaningful insight on the proper design of economic systems.

Evolution of the cosmological horizons in a concordance universe

Energy Technology Data Exchange (ETDEWEB)

Margalef-Bentabol, Berta; Cepa, Jordi [Departamento de Astrofísica, Universidad de la Laguna, E-38205 La Laguna, Tenerife (Spain); Margalef-Bentabol, Juan, E-mail: bmb@cca.iac.es, E-mail: juanmargalef@estumail.ucm.es, E-mail: jcn@iac.es [Facultad de Ciencias Matemáticas, Universidad Complutense de Madrid, Madrid (Spain)

2012-12-01

The particle and event horizons are widely known and studied concepts, but the study of their properties, in particular their evolution, have only been done so far considering a single state equation in a decelerating universe. This paper is the first of two where we study this problem from a general point of view. Specifically, this paper is devoted to the study of the evolution of these cosmological horizons in an accelerated universe with two state equations, cosmological constant and dust. We have obtained simple expressions in terms of their respective recession velocities that generalize the previous results for one state equation only. With the equations of state considered, it is proved that both velocities remain always positive.

Ancient DNA Analysis Suggests Negligible Impact of the Wari Empire Expansion in Peru’s Central Coast during the Middle Horizon

Science.gov (United States)

Barreto Romero, María Inés; Flores Espinoza, Isabel; Cooper, Alan; Fehren-Schmitz, Lars

2016-01-01

The analysis of ancient human DNA from South America allows the exploration of pre-Columbian population history through time and to directly test hypotheses about cultural and demographic evolution. The Middle Horizon (650–1100 AD) represents a major transitional period in the Central Andes, which is associated with the development and expansion of ancient Andean empires such as Wari and Tiwanaku. These empires facilitated a series of interregional interactions and socio-political changes, which likely played an important role in shaping the region’s demographic and cultural profiles. We analyzed individuals from three successive pre-Columbian cultures present at the Huaca Pucllana archaeological site in Lima, Peru: Lima (Early Intermediate Period, 500–700 AD), Wari (Middle Horizon, 800–1000 AD) and Ychsma (Late Intermediate Period, 1000–1450 AD). We sequenced 34 complete mitochondrial genomes to investigate the potential genetic impact of the Wari Empire in the Central Coast of Peru. The results indicate that genetic diversity shifted only slightly through time, ruling out a complete population discontinuity or replacement driven by the Wari imperialist hegemony, at least in the region around present-day Lima. However, we caution that the very subtle genetic contribution of Wari imperialism at the particular Huaca Pucllana archaeological site might not be representative for the entire Wari territory in the Peruvian Central Coast. PMID:27248693

Hawking Radiation from Horizons of Reissner-Nordstroem de Sitter Black Hole with a Global Monopole via Anomalies

International Nuclear Information System (INIS)

Chen Shiwu; Liu Xiongwei; Lin Kai; Zeng Xiaoxiong; Yang Shuzheng

2008-01-01

Hawking radiation from cosmological horizon and event horizon of the Reissner-Nordstroem de Sitter black hole with a global monopole is studied via a new method that was propounded by Robinson and Wilzek and elaborated by Banerjee and Kulkarni. The results show that the gauge current and energy-momentum tensor fluxes, which required keeping gauge covariance and general coordinate invariance at the quantum level in the effective field theory, are exactly equivalent to those of Hawking radiation from the event horizon and the cosmological horizon, respectively

Catalyst-free and solvent-free Michael addition of 1,3-dicarbonyl compounds to nitroalkenes by a grinding method

Science.gov (United States)

Xie, Zong-Bo; Wu, Ming-Yu; He, Ting; Le, Zhang-Gao

2012-01-01

Summary An environmentally benign, fast and convenient protocol has been developed for the Michael addition of 1,3-dicarbonyl compounds to β-nitroalkenes in good to excellent yields by a grinding method under catalyst- and solvent-free conditions. PMID:22563352

VMware Horizon 6 desktop virtualization solutions

CERN Document Server

Cartwright, Ryan; Langone, Jason; Leibovici, Andre

2014-01-01

If you are a desktop architect, solution provider, end-user consultant, virtualization engineer, or anyone who wants to learn how to plan and design the implementation of a virtual desktop solution based on Horizon 6, then this book is for you. An understanding of VMware vSphere fundamentals coupled with experience in the installation or administration of a VMware environment would be a plus during reading.

Thermal ambience of expanding event horizon in Minkowski space-time

International Nuclear Information System (INIS)

Gerlach, U.H.

1983-01-01

It is shown that in flat space-time the thermal ambience of accelerated observers is not associated exclusively with flat event horizons, but arises also with (observer-dependent) event horizons that are light cones. The quanta of this ambience are characterized by a generalized frequency which identifies the representation of the Lorentz group. Global and local model detectors capable of responding to quanta of any given generalized frequency are exhibited. The discussion of the thermal ambience is implemented in terms of a partial-wave analysis using a set of harmonics on the hyperboloid x 2 +y 2 +z 2 -t 2 = 1

Horizon wave-function and the quantum cosmic censorship

Directory of Open Access Journals (Sweden)

Roberto Casadio

2015-07-01

Full Text Available We investigate the Cosmic Censorship Conjecture by means of the horizon wave-function (HWF formalism. We consider a charged massive particle whose quantum mechanical state is represented by a spherically symmetric Gaussian wave-function, and restrict our attention to the superextremal case (with charge-to-mass ratio α>1, which is the prototype of a naked singularity in the classical theory. We find that one can still obtain a normalisable HWF for α22, and the uncertainty in the location of the horizon blows up at α2=2, signalling that such an object is no more well-defined. This perhaps implies that a quantum Cosmic Censorship might be conjectured by stating that no black holes with charge-to-mass ratio greater than a critical value (of the order of 2 can exist.

75 FR 36773 - Pipeline Safety: Updating Facility Response Plans in Light of the Deepwater Horizon Oil Spill

Science.gov (United States)

2010-06-28

... have been, or are subsequently relocated to the Gulf to respond to the Deepwater Horizon event should.... PHMSA-2010-0175] Pipeline Safety: Updating Facility Response Plans in Light of the Deepwater Horizon Oil... 194. In light of the Deepwater Horizon oil spill in the Gulf of Mexico, which has resulted in the...

Organocatalytic Michael and Friedel–Crafts reactions in enantioselective synthesis of biologically active compounds

International Nuclear Information System (INIS)

Maltsev, O V; Beletskaya, Irina P; Zlotin, Sergei G

2011-01-01

Recent applications of organocatalytic Michael and Friedel–Crafts reactions in enantioselective synthesis of biologically active compounds: natural products, pharmaceutical agents and plant protection agents are reviewed. The key mechanisms of stereoinduction, types of organocatalysts and reagents used in these reactions are considered. The material is classified according to the type of newly formed bonds incorporating the asymmetric carbon atom, and the information for the most numerous C–C coupling reactions is systematized according to the natures of the electrophile and the nucleophile. The bibliography includes 433 references.

Receding-horizon control for max-plus linear systems with discrete actions using optimistic planning

NARCIS (Netherlands)

Xu, J.; Busoniu, L; van den Boom, A.J.J.; De Schutter, B.H.K.; Cassandras, Christos G.; Giua, Alessandro; Li, Zhiwu

2016-01-01

This paper addresses the infinite-horizon optimal control problem for max-plus linear systems where the considered objective function is a sum of discounted stage costs over an infinite horizon. The minimization problem of the cost function is equivalently transformed into a maximization problem of

Research Ship New Horizon Underway Meteorological Data, Quality Controlled

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship New Horizon Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

RG flow and thermodynamics of causal horizons in higher-derivative AdS gravity

International Nuclear Information System (INIS)

Banerjee, Shamik; Bhattacharyya, Arpan

2016-01-01

In http://arxiv.org/abs/1508.01343 [hep-th], one of the authors proposed that in AdS/CFT the gravity dual of the boundary c-theorem is the second law of thermodynamics satisfied by causal horizons in AdS and this was verified for Einstein gravity in the bulk. In this paper we verify this for higher derivative theories. We pick up theories for which an entropy expression satisfying the second law exists and show that the entropy density evaluated on the causal horizon in a RG flow geometry is a holographic c-function. We also prove that given a theory of gravity described by a local covariant action in the bulk a sufficient condition to ensure holographic c-theorem is that the second law of causal horizon thermodynamics be satisfied by the theory. This allows us to explicitly construct holographic c-function in a theory where there is curvature coupling between gravity and matter and standard null energy condition cannot be defined although second law is known to hold. Based on the duality between c-theorem and the second law of causal horizon thermodynamics proposed in http://arxiv.org/abs/1508.01343 [hep-th] and the supporting calculations of this paper we conjecture that every Unitary higher derivative theory of gravity in AdS satisfies the second law of causal horizon thermodynamics. If this is not true then c-theorem will be violated in a unitary Lorentz invariant field theory.

Accelerated detectors and worldsheet horizons in AdS/CFT

Science.gov (United States)

Chernicoff, Mariano; Paredes, Angel

2011-03-01

We use the AdS/CFT correspondence to discuss the response of an accelerated observer to the quantum vacuum fluctuations. In particular, we study heavy quarks probing a strongly coupled CFT by analysing strings moving in AdS. We propose that, in this context, a non-trivial detection rate is associated to the existence of a worldsheet horizon and we find an Unruh-like expression for the worldsheet temperature. Finally, by examining a rotating string in global AdS we find that there is a transition between string embeddings with and without worldsheet horizon. The dual picture corresponds to having non-trivial or trivial interaction with the quantum vacuum respectively. This is in qualitative agreement with results of Davies et al.

Casimir effect and thermodynamics of horizon instabilities

International Nuclear Information System (INIS)

Hartnoll, Sean A.

2004-01-01

We propose a dual thermodynamic description of a classical instability of generalized black hole spacetimes. From a thermodynamic perspective, the instability is due to negative compressibility in regions where the Casimir pressure is large. The argument indicates how the correspondence between thermodynamic and classical instability for horizons may be extended to cases without translational invariance

Genome-scale metabolic models applied to human health and disease.

Science.gov (United States)

Cook, Daniel J; Nielsen, Jens

2017-11-01

Advances in genome sequencing, high throughput measurement of gene and protein expression levels, data accessibility, and computational power have allowed genome-scale metabolic models (GEMs) to become a useful tool for understanding metabolic alterations associated with many different diseases. Despite the proven utility of GEMs, researchers confront multiple challenges in the use of GEMs, their application to human health and disease, and their construction and simulation in an organ-specific and disease-specific manner. Several approaches that researchers are taking to address these challenges include using proteomic and transcriptomic-informed methods to build GEMs for individual organs, diseases, and patients and using constraints on model behavior during simulation to match observed metabolic fluxes. We review the challenges facing researchers in the use of GEMs, review the approaches used to address these challenges, and describe advances that are on the horizon and could lead to a better understanding of human metabolism. WIREs Syst Biol Med 2017, 9:e1393. doi: 10.1002/wsbm.1393 For further resources related to this article, please visit the WIREs website. © 2017 Wiley Periodicals, Inc.

Energy and information near black hole horizons

International Nuclear Information System (INIS)

Freivogel, Ben

2014-01-01

The central challenge in trying to resolve the firewall paradox is to identify excitations in the near-horizon zone of a black hole that can carry information without injuring a freely falling observer. By analyzing the problem from the point of view of a freely falling observer, I arrive at a simple proposal for the degrees of freedom that carry information out of the black hole. An infalling observer experiences the information-carrying modes as ingoing, negative energy excitations of the quantum fields. In these states, freely falling observers who fall in from infinity do not encounter a firewall, but freely falling observers who begin their free fall from a location close to the horizon are ''frozen'' by a flux of negative energy. When the black hole is ''mined,'' the number of information-carrying modes increases, increasing the negative energy flux in the infalling frame without violating the equivalence principle. Finally, I point out a loophole in recent arguments that an infalling observer must detect a violation of unitarity, effective field theory, or free infall

Isolated Horizons and Black Hole Entropy in Loop Quantum Gravity

Directory of Open Access Journals (Sweden)

Jacobo Diaz-Polo

2012-08-01

Full Text Available We review the black hole entropy calculation in the framework of Loop Quantum Gravity based on the quasi-local definition of a black hole encoded in the isolated horizon formalism. We show, by means of the covariant phase space framework, the appearance in the conserved symplectic structure of a boundary term corresponding to a Chern-Simons theory on the horizon and present its quantization both in the U(1 gauge fixed version and in the fully SU(2 invariant one. We then describe the boundary degrees of freedom counting techniques developed for an infinite value of the Chern-Simons level case and, less rigorously, for the case of a finite value. This allows us to perform a comparison between the U(1 and SU(2 approaches and provide a state of the art analysis of their common features and different implications for the entropy calculations. In particular, we comment on different points of view regarding the nature of the horizon degrees of freedom and the role played by the Barbero-Immirzi parameter. We conclude by presenting some of the most recent results concerning possible observational tests for theory.

Dropping The Bomb? On Critical and Cinematic Reactions to Michael Ondaatje's The English Patient

OpenAIRE

Pesch, Josef

2018-01-01

This paper analyses Anthony Minghella's film adaptation of Michael Ondaatje’s The English Patient. It aims at establishing patterns of transformation and strategies of adaptation. Not only the nostalgie romanticisation, but also the de-politicisation of the novel is critically scrutinized. As dropping all reference to the atomic bomb from the film is the most blatant example of deviation from the novel, critical and political background is provided which may explain this act of self-censorshi...

A Study of Postmodern Narrative in Michael Cunningham's The Hours

Directory of Open Access Journals (Sweden)

Hajar Abbasi Narinabad

2012-09-01

Full Text Available This project aims at providing a detailed analysis of the major features of the theory of postmodern narrative and at going through the novel The Hours by the American writer Michael Cunningham concentrating on some postmodern narrative techniques. To do so, the researcher goes through the theories set forth by some postmodern theoreticians like Roland Barthes, Jacque Derrida, Jean-François Lyotard and Julia Kristeva to investigate the postmodern narrative techniques and elements used in the novel. The researcher first examines the theories and then critically applies them on the novel. The article goes through the most eminent elements of postmodern narrative including intertextuality, stream of consciousness style, fragmentation and representation respectively which are delicately utilized in The Hours. The article concludes by recommending a few directions for the further research.

Symmetry enhancement of extremal horizons in D  =  5 supergravity

Science.gov (United States)

Kayani, U.

2018-06-01

We consider the near-horizon geometry of supersymmetric extremal black holes in un-gauged and gauged 5-dimensional supergravity, coupled to abelian vector multiplets. By analyzing the global properties of the Killing spinors, we prove that the near-horizon geometries undergo a supersymmetry enhancement. This follows from a set of generalized Lichnerowicz-type theorems we establish, together with an index theory argument. As a consequence, these solutions always admit a symmetry group.