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[en] An extension of the Keski-Vakkuri, Kraus and Wilczek (KKW) analysis to black hole spacetimes which are not Schwarzschild-type is presented. Preserving the regularity at the horizon and stationarity of the metric in order to deal with the across-horizon physics, a more general coordinate transformation is introduced. In this analysis the Hawking radiation is viewed as a tunnelling process which emanates from the non-Schwarzschild-type black hole. Expressions for the temperature and entropy of these non-Schwarzschild-type black holes are extracted. As a paradigm, in the context of this generalization, we consider the Garfinkle-Horowitz-Strominger (GHS) black hole as a dynamical background and we derive the modified temperature and entropy of GHS black hole. Deviations are eliminated and corresponding standard results are recovered to the lowest order in the emitted shell of energy. The extremal GHS black hole is found to be non-'frozen' since it is characterized by a constant non-zero temperature. Furthermore, the modified extremality condition forbids naked singularities to form from the collapse of the GHS black hole
Journal
[en] Recently, it was shown that the entropy of the black hole horizon in the Achucarro-Ortiz spacetime can be described by the Cardy-Verlinde formula. In this Letter, we compute the self-gravitational corrections to the Cardy-Verlinde formula of the two-dimensional Achucarro-Ortiz black hole. These corrections stem from the effect of self-gravitation and they are derived in the context of Keski-Vakkuri, Kraus and Wilczek (KKW) analysis. The black hole under study is therefore treated as a dynamical background. The self-gravitational corrections to the entropy as given by the Cardy-Verlinde formula of the Achucarro-Ortiz black hole, are found to be positive. This result provides evidence in support of the claim that the holographic bound is not universal in the framework of two-dimensional gravity models
Journal
[en] The 5th International Conference on Mathematical Modeling in Physical Sciences (IC- MSQUARE) took place at Athens, Greece, from Monday, 23"t"h of May, to Thursday, 26"t"h of May 2016. The Conference was attended by more than 130 participants and hosted about 170 oral, poster, and virtual presentations while counted more than 500 pre-registered authors. The 5"t"h IC-MSQUARE consisted of different and diverging workshops and thus covered various research fields where Mathematical Modeling is used, such as Theoretical/Mathematical Physics, Neutrino Physics, Non-Integrable Systems, Dynamical Systems, Computational Nanoscience, Biological Physics, Computational Biomechanics, Complex Networks, Stochastic Modeling, Fractional Statistics, DNA Dynamics, Macroeconomics etc. The scientific program was rather heavy since after the Keynote and Invited Talks in the morning, three parallel oral and one poster session were running every day. However, according to all attendees, the program was excellent with high level talks and the scientific environment was fruitful, thus all attendees had a creative time. We would like to thank the Keynote Speaker and the Invited Speakers for their significant contribution to IC-MSQUARE. We also would like to thank the Members of the International Advisory and Scientific Committees as well as the Members of the Organizing Committee. (paper)
Journal
Journal of Physics. Conference Series (Online); ISSN 1742-6596; 
; v. 738(1); [4 p.]
; v. 738(1); [4 p.]
[en] The delineation of the spleen by photoscanning after the intravenous injection of heat-treated Cr51-labelled erythrocytes is valuable when investigating congenital haemolytic anaemias, especially thalassaemia, a disease which is recognized as one of the most important public health problems in Greece. Heat-treated Cr51-labelled erythrocytes were prepared as follows: blood was taken from the subject by venepuncture and delivered into a sterile bottle containing acid-citrate-dextrose. The red cells were separated by centrifugation and the plasma discarded. 50 - 150 μc Cr51-chromate was added to the red cells and the mixture allowed to stand for 30 min at room temperature. The labelled cells were washed once with saline and re-suspended in saline. The suspension was heated at 49.5°C for one hour. The heated cells were washed once with saline and re-suspended in saline. The suspension was then injected intravenously into the subject. Scanning was performed one hour later. Cases of thalassaemia major, sickle cell haemoglobin/thalassaemia and thalassaemia trait have been investigated by this method. All the cases studied, with the exception of one carrier of thalassaemia trait, whose spleen was not palpable, showed varying degrees of splenomegaly. The size and configuration of the spleen could be well demonstrated. A constant finding in spleen scans on patients with congenital haemolytic anaemia, not observed in scans on normal subjects, was the presence of regions of lower average radioactivity throughout the organ. The interpretation of this finding is discussed. (author)
[fr]
La gammagraphie de la rate après injection intraveineuse d’érythrocytes marqués avec siCr et traités thermiquement constitue une méthode de choix pour étudier l’anémie hémolytique congénitale, notamment la thalassanémie, maladie qui constitue l’un des problèmes de santé publique les plus importants en Grèce. Les érythrocytes marqués avec 51Cr et traités thermiquement sont préparés de la manière suivante: après avoir prélevé du sang par ponction dans une veine, on le place dans un flacon stérile contenant un citrate acide et de la dextrose. On sépare à la centrifugeuse les globules rouges du plasma, que l'on jette; après avoir ajouté de 50 à 150 μc de 51Cr sous forme de chromate, on laisse reposer le mélange pendant 30 min à la température de la pièce. Les cellules marquées sont lavées une première fois dans un sérum, puis remises en suspension dans du sérum. Cette suspension est chauffée à 49,5°C pendant une heure, puis lavée de nouveau avec du sérum et remise en suspension dans du sérum. Cette suspension est alors injectée dans une veine du sujet et on procède à la gammagraphie une heure plus tard. Les auteurs ont étudié par cette méthode des cas de thalassanémie majeure, d’anémie à cellules falci- formes et de thalassanémie hétérozygote. A l'exception d’un malade souffrant de thalassanémie hétérozygote, dont la rate n’a pu être palpée, on a constaté dans tous les cas divers degrés d'hypertrophie de la rate. On a pu bien déterminer la dimension et la configuration de la rate. Dans toutes les gammagraphies de la rate de malades souffrant d’anémie hémolytique congénitale, on a noté la présence de zones à radioactivité moyenne plus faible; cette particularité n’à jamais été constatée chez des sujets normaux. Les auteurs discutent l'interprétation de ce phénomène. (author)[es]
El delineamiento del bazo por fotoexplora- ción después de una inyección intravenosa de eritrocitos sometidos a calentamiento y marcados con 51Cr es de suma utilidad para la investigación de las anemias hemolíticas congénitas y, especialmente, delatalasemia, enfermedad que constituye uno de los problemas sanitarios más importantes de Grecia. Los eritrocitos tratados térmicamente y marcados con 51Cr se prepararon de la siguiente manera: se extrajo sangre del paciente por punción de la vena y se trasvasó a un frasco esterilizado que contenía una solución ácida de citrato y dextrosa. Los hematíes se separaron por centrifugación y se desechó el plasma. A los hematíes se añadieron de 50 a 150 μc de cromato-51Cr y la mezcla se dejó en reposo a la temperatura ambiente durante 30 min. Seguidamente se lavaron hematíes una sola vez con suero fisiológico y se pusieron en suspensión. Esa suspensión en suero fisiológico se calentó a 49,5°C durante una hora. Los hematíes se volvieron a lavar con suero fisiológico y se preparó una segunda suspensión que se inyectó intravenosamente al paciente. La exploración se efectuó una hora después. Por este método se han investigado casos de talasemia mayor, anemia drepanocitíca y talasemia hetero- cigótíca. Todos los casos estudiados, exceptuando uno de talasemia heterocigótica, en el que el bazo no era palpable, presentaban grados diversos de esplenomegalia. Se pudo poner de relieve perfectamente el tamaño y la configuración del bazo. Una peculiaridad que aparece constantemente en los centelleogramas esplénicos de enfermos de anemia hemolítica congénita, y que no se observa en los de sujetos sanos, es la presencia, en toda la extensión del órgano, de regiones de radiactividad media reducida. En la memoria se procura interpretar ese dato. (author)[ru]
Poluchenie konturov selezenki s pomoshh'ju foto-skennirovanija posle vnutrivennogo vvedenija termicheski obrabotannyh mechennyh hromom-51 jeritrocitov imeet bol'shoe znachenie pri issledovanii vrozhdennyh gemoliticheskih anemij i v osobennosti talassemii —zabolevanija, kotoroe schitaetsja odnoj iz naibolee ser'eznyh, esli ne samoj ser'eznoj, problemoj zdravoohranenija v Grecii, Termicheski obrabotannye mechennye hromom-51 jeritrocity prigotavlivalis' sledujushhim obrazom: krov' pacienta, vzjataja putem venepunkcii, perelivalas' v steril'nuju kolbu, soderzhashhuju limonnokisluju dekstrozu. Jeritrocity otdeljalis' putem centrifugirovanija, i plazma otbrasyvalas'. K jeritrocitam dobavljali 50 — 150 mkkjuri hromata —hrom-51 i jetu smes' ostavljali na 30 minut pri komnatnoj temperature , Mechenye kletki odnokratno promyvali fiziologicheskim rastvorom i snova suspenzirovali v fiziologicheskom rastvore. Jeta suspenzija nagrevalas' v techenie odnogo chasa pri temperature 49,5°C. Podogretye jeritrocity promyvali v fiziologicheskom rastvore i snova suspenzirovali v fiziologicheskom rastvore. Jetu suspenziju zatem vvodili pacientu vnutrivenno. Cherez chas posle jetogo provodilos' skennirovanie. - Takim metodom byli issledovany bol'nye s klassicheskoj talassemiej, sernovidnokletochnoj talassemiej i pacienty, imejushhie priznaki talassemii. U vseh obsledovannyh bol'nyh, za iskljucheniem odnogo nositelja priznakov talassemii, selezenka kotorogo ne proshhupyvalas', obnaruzhena razlichnaja stepen' splenomegalii. Otchetlivo opredeljalsja razmer i konfiguracija selezenki. Na skennogrammah u pacientov s vrozhdennoj gemoliticheskoj anemiej, ne nabljudaemoj na skennogrammah zdorovyh pacientov, postojanno nahodili oblasti s nizkoj srednej radioaktivnost'ju na protjazhenii vsego organa. Obsuzhdaetsja tolkovanie jetih dannyh. (author)Source
International Atomic Energy Agency, Vienna (Austria); 484 p; Oct 1964; p. 325-335; Symposium on medical radioisotope scanning; Athens (Greece); 20-24 Apr 1964; IAEA-SM--51/16; ISSN 0074-1884; ; 13 refs., 11 figs.
; 13 refs., 11 figs.
[en] Studies concerning the accumulating capacity of native epiphytic bromeliads are of utmost relevance, due to the continuous incorporation of chemical elements provided by these organisms in the ecosystems. Bromeliad species from diverse Sao Paulo State conservation units, Brazil, were sampled for young, mature and old leaves using a sustainable sampling method. By applying INAA, the accumulation of ten chemical elements, i.e. Br, Ca, Co, Fe, K, Na, Rb, Sc, Sr and Zn, was investigated in different leaf vegetative stages. The bromeliads showed divergent chemical element distribution patterns, demonstrating a real complexity in the accumulation and translocation mechanisms utilized by these plants. (author)
Journal
Journal of Radioanalytical and Nuclear Chemistry; ISSN 0236-5731; ; CODEN JRNCDM; v. 282(1); p. 111-115
; CODEN JRNCDM; v. 282(1); p. 111-115
[en] Motivated by the recent work on a new physical interpretation of quasinormal modes by Maggiore, we utilize this new proposal to the interesting case of Kerr black hole. In particular, by modifying Hod's idea, the resulting black hole horizon area is quantized and the resulting area quantum is in full agreement with Bekenstein's result. Furthermore, in an attempt to show that the area spectrum is equally spaced, we follow Kunstatter's method. We propose a new interpretation as a result of Maggiore's idea, for the frequency that appears in the adiabatic invariant of a black hole. The derived area spectrum is similar to that of the quantum-corrected Kerr black hole but it is not equally spaced.
Journal
Journal of High Energy Physics; ISSN 1126-6708; ; v. 11(2008); p. 073
; v. 11(2008); p. 073
[en] Epiphytic bromeliads have been used as biomonitors of air pollution since they have specialized structures in leaves for absorbing humidity and nutrients available in the atmosphere. Leaves of five bromeliad species were collected in the conservation unit Parque Estadual Ilha do Cardoso, Sao Paulo State, Brazil, and analyzed by INAA. Vriesea carinata was the species showing most accumulation, with the highest mass fractions of K, Na, Rb and Zn. Similar results were previously found for the same species collected in the dense ombrophilous forest. Chemical composition of bromeliads provided an indication of the atmosphere status in the conservation unit. (author)
Journal
Journal of Radioanalytical and Nuclear Chemistry; ISSN 0236-5731; ; CODEN JRNCDM; v. 278(2); p. 423-427
; CODEN JRNCDM; v. 278(2); p. 423-427
[en] Resuspended soil and other airborne particles adhered to the leaf surface affect the chemical composition of the plant. A well-defined cleaning procedure is necessary to avoid this problem, providing a correct assessment of the inherent chemical composition of bromeliads. To evaluate the influence of a washing procedure, INAA was applied for determining chemical elements in the leaves of bromeliads from Vriesea carinata species, both non-washed and washed with Alconox, EDTA and bi-distilled water. Br, Ce, Hg, La, Sc, Se, Sm and Th showed higher mass fractions in nonwashed leaves. The washing procedure removed the exogenous material without leaching chemical elements from inside the tissues. (author)
Journal
Journal of Radioanalytical and Nuclear Chemistry; ISSN 0236-5731; ; CODEN JRNCDM; v. 278(2); p. 435-439
; CODEN JRNCDM; v. 278(2); p. 435-439
[en] The accumulation of chemical elements in biological compartments is one of the strategies of tropical species to adapt to a low-nutrient soil. This study focuses on the Atlantic Forest because of its eco-environmental importance as a natural reservoir of chemical elements. About 20 elements were determined by INAA in leaf, soil, litter and epiphyte compartments. There was no seasonality for chemical element concentrations in leaves, which probably indicated the maintenance of chemical elements in this compartment. Considering the estimated quantities, past deforestation events could have released large amounts of chemical elements to the environment. (author)
Journal
Journal of Radioanalytical and Nuclear Chemistry; ISSN 0236-5731; ; CODEN JRNCDM; v. 276(1); p. 221-228
; CODEN JRNCDM; v. 276(1); p. 221-228
[en] In this work we compute the entropy density, speed of sound, and the resulting impact on the bulk viscosity to shear viscosity ratio of an ideal Quark Gluon Plasma when the effects of a generalized uncertainty principle are taken into consideration. When the parameter of the generalized uncertainty principle tends to zero, i.e., , we obtain the value of the speed of sound for the ideal gas of massless particles, i.e., , and we recover the expected result that the bulk viscosity when . In addition, in the high temperature limit, i.e., , the speed of sound satisfies the equation . The consequence this has on the bulk viscosity is that in the high temperature limit, the ratio of the bulk to shear viscosity . Our results suggest that the GUP introduces a scale into the system breaking the a priori conformal invariance of a system of massless noninteracting particles.
Journal
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