Can spaceborne synthetic aperture radar be useful for the mapping of ionospheric disturbances in the Arctic Region?

In this work we study the potential of C-band SAR images to map ionosphere disturbances in the Arctic region. This region is a unique region for ionosphere studies due to the characteristics of the geomagnetic field. In particular, we focus on the SAR interferometry technique as means to measure the temporal variation of propagation delay in correspondence of ionosphere disturbances. This technique provides maps of propagation delay differences between the acquisition dates of the two coherent SAR images needed to estimate the propagation delay over the study area. The high spatial resolution of C-band SAR images, in the order of 25 meters could contribute to the study of spatial distribution of ionosphere disturbances. Digisondes, VLF/ELF receivers and the EISCAT radars in the available in the Arctic region provide the time of ionosphere disturbances due to the solar activity, monitored by the ACE satellite. This allows to select the SAR images to process to map the ionosphere disturbances. The typical spatial coverage and acquisition times of Sentinel-1 images over the Arctic region are reported. A numerical analysis is carried out to estimate the expected ionosphere propagation delay in Sentinel-1 interferograms and so the potential of SAR interferometry to map the effects of ionosphere disturbances

Modal meanings of futurity expressions in English and Serbian; Модальный смысл средств для выражения будущего на английском и сербском языке

Ova disertacija predstavlja ispitivanje modalnih značenja sredstva za izražavanje futuralnosti kao jednog od tri centralna temporalna domena u engleskom i srpskom jeziku. Primarni cilj istraživanja je određivanje sintaksičkih i perifrastičnih struktura koje govornici upotrebljavaju pri ukazivanju na buduće događaje u razmatranim jezicima, kao i opisivanje njihovih značenja. Opisivanje značenja podrazumeva i navođenje i klasifikovanje tipova modalnih značenja sredstava u realnim kontekstima upotrebe. Disertacija nudi odgovore na sledeća pitanja: kojim se sredstvima izražava futuralnost u engleskom i srpskom jeziku; da li govornici oba jezika na raspolaganju imaju iste vrste jezičkih izraza za referiranje na budućnost; koja su modalna značenja prisutna pri upotrebi tih izraza; šta determiniše izbor sredstva od strane govornika; koje su sličnosti i razlike u pogledu modalnih značenja pri referiranju na budućnost u ta dva jezika. S obzirom na to da rad predstavlja kontrastivno istraživanje i da je cilj svakog kontrastivnog istraživanja otkrivanje identičnosti, sličnosti i razlika između jezika koji se kontrastiraju, drugi primarni cilj rada je da se kontrastivnom metodom odrede kontrasti, sličnosti i razlike u načinima referiranja na budućnost u engleskom i srpskom jeziku, kao i sličnosti i razlike među modalnim značenjima sredstava kojima se futuralnost u navednim jezicima izražava. Osnovni metodološki pristup primenjen u istraživanju je deskriptivni pri čemu kvalitativnu analizu upotpunjuje kvantitativna...This thesis is an investigation of the modal meanings of the expressions of futurity as one of the three central temporal domains in the English and Serbian language. The primary goal of the research is to determine the syntactic and periphrastic structures used to refer to future events in the studied languages and to describe their meanings. The description of the meanings comprises specifying and classifying the types of the expressions' modal meanings in real contexts of their use. The dissertation provides answers to the following questions: which grammatical means are used to express futurity in English and Serbian language; whether the same kinds of linguistic expressions for future reference are avialable to speakers of both languages; which modal meanings can be encoded in the use of these expressions; what determines the choice of means; what are the similarities and differences regarding modal meanings when referring to future in these two languages. Since this is a contrastive study, and as the goal of every contrastive study is to present identities, similarities and differences between compared languages, another primary objective of the study is to determine contrasts, similarities and differences in the ways of future reference in English and Serbian applying the contrastive method, as well as the similarities and differences between futurity expressions modal meanings in these languages. The basic methodological approach applied in the research is descriptive with the qualitative analysis being supplemented with the quantitative one..

Urgent hybrid approach in treatment of the acute myocardial infarction complicated by the ventricular septal rupture

Introduction. Ventricular septal rupture (VSR) in the acute myocardial infarction (AMI) is a rare but very serious complication, still associated with high mortality, despite significant improvements in pharmacological and surgical treatment. Therefore, hybrid approaches are introduced as new therapeutical options. Case Outline. We present an urgent hybrid approach, consisting of the initial percutaneous coronary intervention (PCI) of the infarct-related artery, followed by immediate surgical closure of the ventricular septal rupture, for treatment of high risk, hemodynamically unstable female patient with AMI caused by one-vessel disease and complicated by VSR and cardiogenic shock. Since the operative risk was also very high (EUROSCORE II 37%), this therapeutic decision was based on the assumption that preoperative PCI could promptly establish blood flow and thereby lessen the risks, duration and complexity of urgent cardiosurgical intervention, performed on the same day. This approach proved to be successful and the patient was discharged from the hospital on the fifteenth postoperative day in stable condition. Conclusion. In selected cases, with high operative risk and unstable hemodynamic state due to AMI complicated by VSR, urgent hybrid approach consisting of the initial PCI followed by surgical closure of VSR may represent an acceptable treatment option and contribute to the treatment of this complex group of patients

Pseudohypoaldosteronism: report of three cases

Primary pseudohypoaldosteronism type 1 (PHA-1) is a heterogeneous syndrome characterised by salt-wasting due to unresponsiveness of target organ to mineralocorticoids. It is inherited in an autosomal recessive or autosomal dominant pattern, and often is a result of the mutation de novo. It can be sub-classified into two distinguishable clinical entities: renal PHA type 1 (renal PHA-1) and multiple PHA type 1 (multiple PHA-1). Secondary (transient) PHA type 1 is usually associated with urinary tract infections complicating structural urinary tract anomalies. PHA type 2 (PHA-2, Gordon syndrome) is an entity inherited in an autosomal dominant pattern.Three cases of PHA, two with renal PHA-1 and one with secondary PHA type 1, are reported.In all patients with salt-wasting and dehydration differentiation between congenital adrenal hyperplasia and PHA should be performed. Also, in the case with hyperkalaemia, hyponatremia and metabolic acidosis, urinary tract infection and obstructive uropathy should be excluded.Keywords: child, pseudohypoaldosteronism, renal type, transien

Multifunctionalized Self-supported (Nano) Membranes as Integrated Platform for Plasmonic Metamaterials

We considered the possibility to fabricate multifunctional nanocomposite membranes as a platform for plasmonic metamaterials, simultaneously incorporating pores, built-in functional groups and active nanoparticles. To this purpose we combined lamination and inclusion of nanofillers into the membrane host. For the basic material we chose macroporous crosslinked copolymers based on glycidyl methacrylate (GMA). The epoxy group present in GMA molecule is readily transformed into various functional groups that further serve as affinity enhancers, ensuring the usability of the membranes as pre-concentrators of selected agents in plasmonic sensors. To form GMA-based membranes we used a recently proposed method combining the traditional immersion precipitation with photopolymerization and crosslinking of functional monomers. Further functionalization is obtained by in-situ formation of noble metal nanoparticles directly within the GMA host. In this way membranes with simultaneous plasmonic, adsorbent and catalytic functionality are obtained. We considered the use of the our structures for plasmonic chemical sensors where separator, pre-concentrator and binding agent are integrated with the plasmonic crystal, as well as for plasmonic enhancement of photocatalytic reactions in microreactors. Our approach gives a highly tailorable element compatible with microelectromechanical systems (MEMS) technologies and readily transferable across platforms

Page Curve for Eternal Schwarzschild Black Hole in Dimensionally-Reduced Model of Dilaton Gravity

As a contribution to the subject of the information loss paradox in (1+1)-dimensional gravitational systems, we study a model of (1+1)-dimensional dilaton gravity derived from the four-dimensional Einstein-Hilbert action by dimensional reduction. The reduced action involves the cosmological constant and admits black hole solutions. After including the back-reaction of quantum fields to 1-loop order, we solve the semi-classical field equations perturbatively and compute the quantum correction to the Hawking temperature. We consider the quantum extremal surface approach and invoke the ``island rule'' to compute the fine-grained entropy of the Hawking radiation for an eternal Schwarzschild black hole and demonstrate that it follows the unitary Page curve.Comment: 11 pages, 4 figure

Silver nanoparticles within functionalized hydrogels for plasmonic (bio)chemical sensors

Plasmonics is the basis for a novel generation of adsorption-based ultrasensitive (bio) chemical sensors. In nanoplasmonic sensors one utilizes nanocomposites typically in the form of thin films, comprising metal nanoparticles or ordered metal-dielectrics (plasmonic crystals). In this work we investigated thin functionalized hydrogel films with embedded silver nanoparticles. These films were prepared by copolymerizing glycidyl methacrylate with mono and multifunctional methacrylates using UV irradiation. The epoxy group in glycidyl methacrylate can then be converted by chemical means into a desired functionality to capture the targeted analyte. Silver nanoparticles were either photochemically generated in situ, or were introduced into hydrogels by chemical reduction. Differences in morphology and performance of these nanocomposites were investigated and will be discussed

Tranzicija u Srbiji u kontekstu suzbijanja korupcije

Tranzicija je dugotrajan proces koji zahteva duboke rezove u ravni ideja, vrednosti, morala, pravnih normi, ekonomskih postulata, organizacije državne vlasti. U periodu tranzicije, tokom transformacije države i društva, gledano sa aspekta pojedinca, potrebno je podanika preobraziti u građanina. Takvo preobraženje mora biti autentično — tokom njega subjekat se autentično transformiše bez direktivnih nametanja, putem obezbeđenja socijalnopolitičke infrastrukture podsticaja koja omogućava da se izvrši prilagođavanje novim okolnostima. Država bi trebalo da tokom ovog procesa ostvaruje ulogu kreatora opšteg normativnog okvira koji građanima pruža jednaka prava, dostupnost institutima i instrumentima za ostvarenje i zaštitu ustanovqenih vrednosti i prava, kao i entiteta koji kreira socijalno-političko okruženje koje omogućava pluralitet glasova. U kontekstu tako definisanih društvenih vrednosti, korupcija se pozicionira kao razarajuća društvena pojava, a društvena praksa promocije integriteta kao bazični način da se kulturno uobliči zajednica u odnosu na date vrednosti

Examination of epidemiological, clinical and pathohistological characteristics of helicobacter pylori infection in HIV infected patients

Pacijenti koji su inficirani virusom humane imunodeficijencije (HIV), tokom svoje bolesti, imaju različite gastrointestinalne simptome koji uključuju i dispepsiju. Gastrointestinalni simptomi mogu biti posledica dejstva samog HIV-a, različitih oportunističkih i ne-oportunističkih infekcija uključujući i infekciju sa Helicobacter pylori (H. pylori), kao i negativne efekte visoko aktivne antiretrovirusne terapije (HAART). H. pylori ima glavnu ulogu u patogenezi hroničnog gastritisa, peptičke ulkusne bolesti, karcinoma želuca, MALT limfoma i nekoliko ekstra-gastričnih manifestacija. Ona je jedan od najznačajnijih bakterijskih patogena u opštoj populaciji, a prevalencija ove infekcije se procenjuje na više od 50% u svetskoj populaciji. Faktori rizika i putevi prenosa ove infekcije su još uvek nedovoljno jasni. Prevalencija H. pylori infekcije kod ljudi koji su inficirani HIV-om (PLHIV) varira od 10 do 76%, zavisno od vremenskog perioda kada je rađeno istraživanje, geografske lokalizacije i populacije. Studije koje su rađene ranije, prijavile su nižu prevalenciju ove koinfekcije kod PLHIV u poređenju sa HIV negativnim kontrolama, suprotno novijim podacima, u modernoj - sadašnjoj HAART eri, u kojoj se prevalenija H. pylori infekcije kod PLHIV približava prevalenciji koja postoji u opštoj populaciji. Cilj: Procena učestalosti H. pylori infekcije u populaciji HIV-om inficiranih u odnosu na kontrolnu grupu sa H. pylori monoinfekcijom, povezanosti imunskog statusa sa dispeptičnim simptomima, endoskopskim i patohistološkim nalazima sluznica želuca i dvanaestopalačnog creva, zatim procena uticaja antiretrovirusne terapije (ART) na učestalost H. pylori koinfekcije i patohistološki nalaz sluznice želuca i ispitivanje faktora rizika za H. pylori infekciju kod inficiranih HIV-om u odnosu na kontrolnu grupu. Materijali i metode: Istraživanje je sprovedeno kao studija slučajeva i kontrola u periodu od 01.01.1993. godine do 31.12.2015. godine u Beogradskoj Klinici za infektivne i tropske bolesti Kliničkog centra Srbije...People living with HIV infection (PLHIV), during their lifetime of illness, suffer from a variety of gastrointestinal (GI) symptoms, including dyspepsia. GI symptoms may occur due to HIV itself, adverse effects of highly active antiretroviral therapy (HAART), or due to a variety of opportunistic and non – opportunistic infections. H. pylori has a key role in pathogenesis of chronic gastritis, peptic ulcer disease, gastric cancer, MALT lymphoma and a few extra - gastric manifestations. It’s one of the most important bacterial pathogens in the general population worldwide, with the estimated prevalence of more than 50%. The risk factors and transmission pathways for this infection have not yet been fully clarified. The prevalence of H. pylori infection in PLHIV varies between 10 and 76%, depending on the period in which different research was conducted, geographical position and population. Research that was done earlier reported lower prevalence of H. pylori and HIV co-infection compared to HIV negative control groups, contrary to newer data in modern HAART era, in which the prevalence of H. pylori infection in PLHIV approaches the prevalence in general population. Goal: Estimating the frequency of H. pylori co-infection in PLHIV compared to control group, assessing the correlation between immune status and dyspeptic symptoms, endoscopic and pathohistological findings of ventricular and duodenal mucous membranes, estimating effects of HAART on the frequency of H. pylori and HIV co-infection and pathohistological findings of ventricular mucous membrane and revealing the risk factors for H. pylori and HIV co-infection in comparison to the control group. Methods: This case – control study was conducted for the period between 1st January 1993 and 31st December 2015 at University Hospital for Infectious and Tropical Diseases, Clinical Centre of Serbia, Belgrade. The study included all the patients who were, for the aforecited period of time, due to dyspeptic symptoms, subjected to esophagogastroduodenoscopy (EGDS) with gastric and duodenal tissue biopsy and histological examination of sampled material..

SIGNIFICANCE OF THERAPY MONITORING OF IMMUNOSUPPRESSIVE MEDICINES IN RENAL TRANSPLANTATION PATIENTS

Immunosuppressive medicines are characterized by specific pharmacokinetic profile which requires therapy monitoring by means of measuring their blood concentrations. Therapy monitoring, by means of determining blood concentration of the medicine, enables application of an optimal individual immunosuppressive therapy. Due to its variable pharmacokinetics, and small therapeutic index and potential interaction with numerous other medicines, the post-operative monitoring of immunosuppressive medicines is an essential element of therapy protocol for renal transplantation patients. Therapy monitoring represents an efficient way to reduce adverse effects of immunosuppressive medicines and to prevent transplantation rejection, by means of adapting the doses in renal transplantation patients. Determining the concentration of immunosuppressive medicines is of special importance in the modified dosing for patients with renal insufficiency. Pharmacokinetic analysis is important for proper interpretation of immunosuppressive medicines' blood concentrations. The interpretation of the received results must be multidisciplinary, considering that there are numerous factors of variability of patients and immunosuppressive medicines