Meron excitations in the nu =1 quantum Hall bilayer and the plasma analogy

We study meron quasiparticle excitations in the \nu = 1 quantum Hall bilayer. Considering the well known single meron state, we introduce its effective form, valid in the longdistance limit. That enables us to propose two (and more) meron states in the same limit. Further, establishing a plasma analogy of the (111) ground state, we find the impurities that play the role of merons and derive meron charge distributions. Using the introduced meron constructions in generalized (mixed) ground states and corresponding plasmas for arbitrary distance between the layers, we calculate the interaction between the construction implied impurities. We also find a correspondence between the impurity interactions and meron interactions. This suggests a possible explanation of the deconfinement of the merons recently observed in the experiments.Comment: 5 pages, 3 figure

Composite bosons in bilayer nu = 1 system: An application of the Murthy-Shankar formalism

We calculate the dispersion of the out-of-phase mode characteristic for the bilayer nu = 1 quantum Hall system applying the version of Chern-Simons theory of Murthy and Shankar that cures the unwanted bare electron mass dependence in the low-energy description of quantum Hall systems. The obtained value for the mode when d, distance between the layers, is zero is in a good agreement with the existing pseudospin picture of the system. For d nonzero but small we find that the mode is linearly dispersing and its velocity to a good approximation depends linearly on d. This is in agreement with the Hartree-Fock calculations of the pseudospin picture that predicts a linear dependance on d, and contrary to the naive Hartree predictions with dependence on the square-root of d. We set up a formalism that enables one to consider fluctuations around the found stationary point values. In addition we address the case of imbalanced layers in the Murthy-Shankar formalism.Comment: 10 pages, 1 figur

The Line Emission Region in III Zw 2: Kinematics and Variability

We have studied the Ly-al, Hbeta, Halpha and Mg II2798 line profiles of the Seyfert 1 galaxy III Zw 2. The shapes of these broad emission lines show evidence of a multicomponent origin and also features which may be identified as the peaks due to a rotating disk. We have proposed a two-component Broad Line Region (BLR) model consisting of an inner Keplerian relativistic disk and an outer structure surrounding the disk. The results of the fitting of the four Broad Emission Lines (BELs) here considered, are highly consistent in both the inner and outer component parameters. Adopting a mass of approx. 2 E8 sollar masses for the central object we found that the outer radius of the disk is approximately equal for the four considered lines (approx 0.01 pc). However, the inner radius of the disk is not the same: 0.0018 pc for Ly-alpha, 0.0027 pc for Mg II, and 0.0038 pc for the Balmer lines. This as well as the relatively broad component present in the blue wings of the narrow [OIII] lines indicate stratification in the emission-line region. Using long-term Hbeta observations (1972-1990, 1998) we found a flux variation of the BEL with respect to the [OIII] lines.Comment: ApJ, accepted, 22 pages, 10 figure

Mangan-superoksid-dismutaza (MnSOD) katalizuje NO-zavisno nitrovanje ostatka tirozina

The peroxynitrite-induced nitration of manganese superoxide dismutase (MnSOD) tyrosine residue, which causes enzyme inactivation, is well established, This led to suggestions that MnSOD nitration and inactivation in vivo, detected in various diseases associated with oxidative stress and overproduction of nitric monoxide (NO), conditions which favor peroxynitrite formation, is also caused by peroxynitrite. However, our previous ill vitro study demonstrated that exposure of MnSOD to NO led to NO conversion into nitrosonium (NO+) and nitroxyl (NO-) species, which caused enzyme modifications and inactivation. Here it is reported that MnSOD is tyrosine nitrated upon exposure to NO, as well as that MnSOD nitration contributes to inactivation of the enzyme. Collectively, these observations provide a compelling argument supporting the generation of nitrating species in MnSOD exposed to NO and shed a new light on MnSOD tyrosine nitration and inactivation ill vivo. This may represent a novel mechanism by which MnSOD protects cell from deleterious effects associated with overproduction of NO. However, extensive MnSOD modification and inactivation associated with prolonged exposure to NO will amplify the toxic effects caused by increased cell superoxide and NO levels.Dobro je poznato da peroksinitrit izaziva nitrovanje ostataka tirozina u mangan-superoksid- dismutazi (MnSOD) što dovodi do inaktivacije enzima. Pokazano je da nitrovanje i inaktivacija MnSOD-a nastaje u raznim bolestima za koje je karakteristič an oksidativni stres i povećana produkcija azot-monoksida (NO). Pošto se pri ovim uslovima očekuje nastajanje peroksinitrita predloženo je da peroksinitrit izaziva nitrovanje i inaktivaciju MnSOD in vivo. U našem prethodnom radu pokazali smo da MnSOD katalizuje transformaciju NO u nitrozonijum (NO+) i nitroksil (NO–) reaktivne vrste, te identifikovali neke od modifikacija molekula enzima koje pri tome nastaju izazivajući njegovu inaktivaciju. U ovom radu je pokazano da pri izlaganju MnSOD azot-monoksidu dolazi i do nitrovanja ostatka tirozina u molekulu enzima, što doprinosi njegovoj inaktivaciji. Ovi rezultati ukazuju da pri interakciji MnSOD sa NO dolazi do nastajanja nitrujućih vrsta, što baca novo svetlo na proces nitrovanja ostataka tirozina i inaktivaciju MnSOD in vivo. Ovo može da predstavlja novi mehanizam kojim MnSOD štiti ćeliju odštetnih efekata izazvanih hiperprodukcijom azot-monoksida. Međutim ekstenzivne modifikacije i inaktivacija MnSOD do kojih dolazi pri produženom izlaganju enzima NO, uvećaće toksične efekte izazvane povećanim koncentracijama superoksida i NO u ćeliji

Bridge deck runoff control trough drainage, treatment and irrigation system: The case study of the bridge Ostruznica over the Sava river

The paper presents main design project of the bridge Ostruznica deck drainage and runoff treatment. An integral solution of drainage and irrigation and/or discharge water into the Sava river of pre - treated runoff from the portion of highway Dobanovci – Bubanj Potok and the bridge The treated water is taken for irrigation into the groundwater as a recharge, along the series of wells for potable water within sanitary protection zone of the Belgrade Water supply system. The first flush of the criteria rainfall runoff volume is to be pre - treated using a StormwaterR barrels. Such a solution is considered as an additional water source at the aquifer by the rivers’ banks. Also, it is a measure of water cycle improvement. The project is completed by a SwermR preventing system for accidental situation, such as leakage or accidents of vehicles and potential pollution and risks of vulnerability for the potablewater wells

Due Auswahl der Experimentellen tiere in der untersuchung des parodontium

Mnogi problemi etiologije i patogeneze progresivnih parodontopatija još uvek nisu rešeni. Neophodna su buduća naučna istraživanja, u in vivo uslovima. Data je analiza osobina nekih eksperimentalnih životinja, bazirana na podacima iz literature i sopstvenom iskustvu. Izbor eksperimentalnih životinja, kao modela za parodontalna istraživanja, sa prednostima domaće svinje u eksperimentalne svrhe, autori su prodiskutovali sa posebnom pažnjom.A number of etiological and pathogenetic problems related to parodontal diseases are still insufficiently clarified. Further in vivo studies are necessary. The analyses of properties of some experimental animals based on literature data and own experience are presented. Particular attention is payed to the selection of experimental animal as a model for parodontal studies. Advantages of using domestic swine for xperimental purposes are discussed in details.Viele Probleme der Aetiologie und der Pathogenese der progressiven Parodontopathie sind noch nicht gelöst. Wissenschaftliche Forschungen in vivo scheinen uns nötig zu sein. Eigenschaften einiger experimentellen Tiere, aufgrund von Angaben aus der Literatur und anhand eigener Erfahrungen, werden angeführt. Die Autoren haben die Auswahl der experimentellen Tiere, die zu Versuchszwecken für parodontale Untersuchungen verwendet wurden, gründlich überprüft, mit besonderer Berücksichtigung der Experimente mit Schweinen

Supplementary data for article: Dimitrijević, M. S.; Bogdanović Pristov, J.; Žižić, M.; Stanković, D. M.; Bajuk-Bogdanović, D.; Stanić, M.; Spasić, S.; Hagen, W.; Spasojević, I. Biliverdin-Copper Complex at Physiological PH. Dalton Transactions 2019, 48 (18), 6061–6070. https://doi.org/10.1039/c8dt04724c

Supplementary material for: [https://pubs.rsc.org/en/content/articlelanding/2019/DT/C8DT04724C#!divAbstract]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/3066]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3068