A dark energy view of inflation

Traditionally, inflationary models are analyzed in terms of parameters such as the scalar spectral index ns and the tensor to scalar ratio r, while dark energy models are studied in terms of the equation of state parameter w. Motivated by the fact that both deal with periods of accelerated expansion, we study the evolution of w during inflation, in order to derive observational constraints on its value during an earlier epoch likely dominated by a dynamic form of dark energy. We find that the cosmic microwave background and large-scale structure data is consistent with w_inflation=-1 and provides an upper limit of 1+w <~ 0.02. Nonetheless, an exact de Sitter expansion with a constant w=-1 is disfavored since this would result in ns=1.Comment: 5 pages, 4 figures; v2: minor modifications to match published versio

On the Topological Resonance Energy of Coumarin and Its Derivates

Topological resonance energies of coumarin and the following derivatives: 3-hydroxycoumarin, 4-hydroxycoumarin, 3,4-dihydro-. xycoumarin, 4,6-dihydroxycoumarin, 4,5,7-trihydroxycoumarin, 3- -carboxy-4-hydroxycoumarin, 3-bromo-4-hydroxycoumarin, and 6-bromo-4-hydroxycoumarin, are reported. Theoretical predictions that these all coumarins should exhibit aromatic properties are sustained by the ample experimental evidence. In addition, coumarin and isocoumarin are predicted to be much more stable than the corresponding quinonoid isomer

RXJ 0921+4529: a binary quasar or gravitational lens?

We report the new spectroscopic observations of the gravitational lens RXJ 021+4529 with the multi-mode focal reducer SCORPIO of the SAO RAS 6-m telescope. The new spectral observations were compared with the previously observed spectra of components A and B of RXJ 0921+4529, i.e. the same components observed in different epochs. We found a significant difference in the spectrum between the components that cannot be explained with microlensing and/or spectral variation. We conclude that RXJ 0921+4529 is a binary quasar system, where redshifts of quasars A and B are 1.6535 +/- 0.0005 and 1.6625 +/- 0.0015, respectively.Comment: 6 pages, 5 figures, accepted for publication in The Astrophysical Journal Letter

Transient Stability Simulation by Waveform Relaxation Methods

In this paper, a new methodology for power system dynamic response calculations is presented. The technique known as the waveform relaxation has been extensively used in transient analysis of VLSI circuits and it can take advantage of new architectures in computer systems such as parallel processors. The application in this paper is limited to swing equations of a large power system. Computational results are presented

Revealing the nature of central emission nebulae in the dwarf galaxy NGC 185

In this paper we present new optical observations of the galaxy NGC 185 intended to reveal the status of supernova remnants (SNRs) in this dwarf companion of the Andromeda galaxy. Previously, it was reported that this galaxy hosts one SNR. Our deep photometric study with the 2m telescope at Rozhen National Astronomical Observatory using narrow-band H$\alpha$ and [SII] filters revealed complex structure of the interstellar medium in the center of the galaxy. To confirm the classification and to study the kinematics of the detected nebulae, we carried out spectroscopic observations using the SCORPIO multi-mode spectrograph at the 6m telescope at the Special Astrophysical Observatory of the Russian Academy of Science, both in low- and high-resolution modes. We also searched the archival X-ray and radio data for counterparts of the candidate SNRs identified by our optical observations. Our observations imply the presence of one more SNR, one possible HII region previously cataloged as part of an SNR, and the presence of an additional source of shock ionization in one low-brightness PN. We detected enhanced [SII]/H_alpha and [NII]/H_alpha line ratios, as well as relatively high (up to 90 km s$^{-1}$) expansion velocities of the two observed nebulae, motivating their classification as SNRs (with diameters of 45 pc and 50 pc), confirmed by both photometric and spectral observations. The estimated electron density of emission nebulae is 30 - 200 cm$^{-3}$. Archival XMM-Newton observations indicate the presence of an extended, low-brightness, soft source in projection of one of the optical SNRs, whereas the archival VLA radio image shows weak, unresolved emission in the center of NGC 185.Comment: 15 pages, 14 figures, accepted for publication in A&

An overview of generalized entropic forms

The aim of this focus letter is to present a comprehensive classification of the main entropic forms introduced in the last fifty years in the framework of statistical physics and information theory. Most of them can be grouped into three families, characterized by two-deformation parameters, introduced respectively by Sharma, Taneja, and Mittal (entropies of degree $(\alpha,\,\beta$)), by Sharma and Mittal (entropies of order $(\alpha,\,\beta)$), and by Hanel and Thurner (entropies of class $(c,\,d)$). Many entropic forms examined will be characterized systematically by means of important concepts such as their axiomatic foundations {\em \`{a} la} Shannon-Khinchin and the consequent composability rule for statistically independent systems. Other critical aspects related to the Lesche stability of information measures and their consistency with the Shore-Johnson axioms will be briefly discussed on a general ground.Comment: 14 pages, 6 tables, no figures, to appear on EPL: Focus Issues "Progresses on Statistical Physics and Complexity

Homodiegetic narration in the Serbian novel ; Гомодиегетическое повествование в сербском романе.

Рад представља покушај теоријског укрштања два различита књижевнонаучна приступа: са једне стране непосредно је заснован на наратолошким поставкама најутицајнијих аутора краја ХХ века (посебно на Женетовој теорији приповедања), док са друге подразумева јасну књижевноисторијску перспективу, и то жанровски прецизно профилисану ‒ организован је као једна специфична повест српског романа. Извршено читалачко истраживање и анализа текстова тежили су да у исто време обухвате и поступке и облике, односно да испитају примену једне посебне приповедне технике (хомодијегетичког приповедања) у конкретној прозној форми (роману) у дужој дијахронијској перспективи. Показало се да је прича о хомодијегетичком роману у исто време и повест српског романа у целини...The work represents an attempt at theoretical cross-section between two different literary scholarship approaches: on the one hand it is indirectly based on narrative settings of the most influential authors of the end of the twentieth century (especially on Genette’s narrative theory), while on the other hand it implies a clear literary-historical perspective which is organized as a specific history of the Serbian novel. The carried out book research and text analyses aspired to comprise both techniques and forms at the same time, i.e. to explore the implementation of a special narrative technique (homodiegetic narration) in a prose form (novel) in a long-term diachronic perspective. The story about the homodiegetic novel has proved to be the history of the Serbian novel at the same time..

Micromorphological characteristics of the distal segment and braches of the radial artery

Hirurške procedure, kao što je odizanje tenarnih režnjeva ili stabla radijalne arterije, traže detaljno poznavanje anatomije stabla i grana a. radialis (AR). Ciljevi ove disertacije bili su da se definišu pružanje i šema grananja radijalne arterije i njenih grana, i da se definišu morfometrijske karakteristike i varijacije radijalne arterije i njenih grana. Eksperimentalno istraživanje distalnog segmenta radijalne arterije je obavljeno na 50 podlaktica i šaka kadavera (leševa) oba pola. Krvni sudovi 15 podlaktica i šaka su perfundovani toplim fiziološkim rastvorom i neutralnim formalinom (4% neutralni rastvor formaldehida) nakon čega je izvršeno ubrizgavanje 10% tuš želatina u proksimalni deo stable radijalne arterije. Ovi preparati su korišćeni za mikrodisekciju distalnog dela radijalne arterije i njenih grana u cilju proučavanja morfologije, topografskih odnosa i anastomoza ovih krvnih sudova. Drugi deo istraživanja je izveden ubrizgavanjem metil metakrilata u arterijski sistem 35 podlaktica i šaka i naknadno sprovedenom korozijom u 40% rastvoru KOH što nam je omogućilo da dobijemo plastične odlivke arterijske mreže distalnog dela radijalne arterije na kojima su vršena merenja istraživanih krvnih sudova. Dalja mikroanatomska istraživanja su obuhvatala tri dela distalnog segmenta žbične arterije (a. radialis): 1) stablo distalnog segmenta a. radialis (AR), 2) a. princeps pollicis (APP) i 3) arcus palmaris profundus (ArcPP). Posebno smo izdvojili r. palmaris superficialis (RPS) i aa. metacarpales dorsales (AMD). Prečnik distalnog dela stabla a. radialis (AR) u nivou zgloba ručja iznosio je prosečno 2,9±0,3 mm. R. palmaris superificialis (RPS) je identifikovan na svim preparatima (100%). RPS se u većini slučajeva (75% preparata) pružao potkožno i njegov prosečan dijametar (prečnik) je iznosio 1,42±0,45 mm. Definisali smo postojanje dva tipa RPS: dobro razvijen RPS (tip A) i hipoplastičan RPS (tip B). Dobro razvijen RPS (tip A) bio je prisutan na 11 (31,4%) preparata, odlikovale su ga vrednosti dijametra koje su bile veće od 1,7 mm, pri čemu je vrednost njegovog prosečnog dijametra iznosila 1,95±0,36 mm. Ovaj tip RPS je učestvovao u vaskularizaciji kažiprsta, a zavisno od uključenosti u vaskularizaciju palca izdvojili smo podtip A1, koji je bio prisutan u 6 (17,1%) slučajeva i podtip A2 koji je bio nešto ređi, 4 (11,4%) slučajeva...Surgical procedures such as the thenar flaps and radial artery (RA) harvesting call for an detailed anatomical study of the radial artery and its branches. The aims of this dissertation were to define the extent and branching patterns of the distal segment and branches of the radial artery, as like as to define the morphometric characteristics and anatomical variations of these blood vessels. The distal segment of the RA and its branches were investigated in 50 postmortem specimens of human forearms and hands. In the first part of our study, 15 specimens of the forearms and hands were perfused with 0.9% saline solution and buffered formalin (4% neutral solution of formaldehyde), and further injected with black India ink. These specimens were used for the microdissection of the distal segment of the RA and its branches in order to investigate the morphology, topographic relationships and anastomoses of these blood vessels. Second part of our study was performed in 35 specimens of the forearms and hands we injected with methyl-methacrylate and afterwards corroded in 40% potassium hydroxide solution. Using this method we obtained corrosion plastic casts in order to perform measurements of investigated blood vessels. Further microanatomical studies covered three parts of the distal segment of the RA: 1) the main stem of the distal segment of the RA, 2) the princeps pollicis artery (PPA) and 3) the deep palmar arch (DPA), including the superficial palmar branch and dorsal metacarpal arteries (DMA). The average diameter of the main stem of the RA distal segment was 2.9±0.3 mm. The superficial palmar branch (SPB) of the RA was always present and in the majority of cases the course of the SPB was superficial (75%). The mean diameter of the SPB was 1.42±0.45 mm. We defined two types of the SPB according to its diameter: well developed SPB (type A) and hypoplastic SPB (type 2). Well developed SPB (type A) was present in 11 hands (31.4% of cases) with the diameter larger than 1.7 mm (mean diameter of 1.95±0.36 mm) and it was extending distally in order to continue as the radialis indicis artery (RIA). This type of the SPB supplied the index finger and it gave of two important branches to the thumb we further classified as the A1 subtype, which was present in 6 hands (17.1% of cases) and A2 subtype, which was present in 4 hands (11.4% of cases)..