Nonparabolicity effects and the spin-split electron dwell time in symmetric III-V double-barrier structures

We start from the fourth order nonparabolic and anisotropic conduction band bulk dispersion relation to obtain an one-band effective Hamiltonian which we apply to an AlGaSb symmetric double-barrier structure with resonant energies significantly (more than 200meV) above the well bottom. The spin-splitting is described by the k3 Dresselhaus spin-orbit coupling term modifying only the effective mass of the spin eigenstates in the investigated structure. Apart from the bulk-like resonant energy shift due to the band nonparabolicity, we obtain a substantial shift depending on the choice of boundary conditions for the envelope functions at interfaces between different materials. The shift of resonant energy levels leads to the change of spin-splitting and the magnitude of the dwell times. We attempt to explain the influence of both the nonparabolicity and boundary conditions choice by introducing various effective masses

Time delay in thin slabs with self-focusing Kerr-type nonlinearity

Time delays for an intense transverse electric (TE) wave propagating through a Kerr-type nonlinear slab are investigated. The relation between the bidirectional group delay and the dwell time is derived and it is shown that the difference between them can be separated into three terms. The first one is the familiar self interference time, due to the dispersion of the medium surrounding the slab. The other two terms are caused by the nonlinearity and oblique incidence of the TE wave. It is shown that the electric field distribution along the slab may be expressed in terms of Jacobi elliptic functions while the phase difference introduced by the slab is given in terms of incomplete elliptic integrals. The expressions for the field intensity dependent complex reflection and transmission coefficients are derived and the multivalued oscillatory behavior of the delay times for the case of a thin slab is demonstrated

Non-commutative SU(N) gauge theories and asymptotic freedom

In this paper we analyze the one-loop renormalization of the $\theta$-expanded $\rm SU(N)$ Yang-Mills theory. We show that the {\it freedom parameter} $a$, key to renormalization, originates from higher order non-commutative gauge interaction, represented by a higher derivative term $b h \theta^{\mu\nu}\hat F_{\mu\nu}\star\hat F_{\rho\sigma}\star\hat F^{\rho\sigma}$. The renormalization condition fixes the allowed values of the parameter $a$ to one of the two solutions: $a=1$ or $a=3$, i.e. to $b=0$ or to $b=1/2$, respectively. When the higher order interaction is switched on, ($a=3$), pure non-commutative SU(N) gauge theory at first order in $\theta$-expansion becomes one-loop renormalizable for various representations of the gauge group. We also show that, in the case $a=3$ and the adjoint representation of the gauge fields, the non-commutative deformation parameter $h$ has to be renormalized and it is asymptotically free.Comment: 16 pages, no figure

Effects of induced maternal hypothyroidism on the ovarian development of offspring rats

The effects of propylthyouracil (PTU) induced hypothyroidism of rats during pregnancy and lactation on offspring ovarian development and maturation were studied. Thyroid hormones and thyroid stimulating hormone (TSH) concentrations were determined using the radioimmunoassay method in order to verify the hypothyroid status of treated mothers and their two months old pups. The ovaries of the offspring were processed for light microscopy analysis on the day of the first estrus after the 60th day of age. Histological analysis including follicle count was performed on serial sections stained with haematoxyline/eosin and on semithin sections stained with methylene blue. A significant increase of serum TSH and decrease in T3 and T4 levels was observed in treated mothers compared to controls. The levels of measured hormones in the control and PTU-treated two months old rats were not significantly different. Ten percent of 60-dayold treated females did not reach estrus and they were sacrificed in diestrus. The secondary interstitial cells were the dominant structures in the ovaries. The number of healthy growing and early antral follicles was markedly decreased. Ovaries of treated rats contained relatively few antral follicles, significantly more atretic antral follicles and a decreased number of corpora lutea, compared to controls. These results indicate that lack of thyroid hormones during prenatal and early postnatal development impair ovarian development in rats. [Projekat Ministarstva nauke Republike Srbije, br. 175061

NPD in small manufacturing enterprises in Serbia

New product development in small manufacturing enterprises on the territory of Serbia was investigated on a representative sample of micro and small enterprises covering a broad range of businesses. It was found that market pull was the prevalent strategy for new product development, which was characterized by close collaboration with customers from the idea to the final product including the R&D activities. Besides customers, the main sources of ideas were competitors and trade fairs or exhibitions. The marketing activities associated with new product introduction were quite limited. These findings were compared with new product development practices in neighboring countries. Based on our findings we propose two measures to improve new product development in small manufacturing enterprises in Serbia: establish a closer cooperation with external knowledge centers (universities, research institutes, innovation centers) and set up innovation networks with complementary partners by actively using the open innovation concept.This is the peer reviewed version of the following article: Vorkapić, Miloš, Filip Radovanović, Dragan Ćoćkalo, and Dejan Đorđević. 2017. “NPD u malim proizvodnim poduzećima u Srbiji.” Tehnički vjesnik 24 (1): 327-332. [http://dx.doi.org/10.17559/TV-20150807185156

Edem mozga kod zavisnika od droge

Background/Aim. The effect of drugs leaves permanent consequences on the brain, organic in type, followed by numerous manifestations, and it significantly affects the development of mental dysfunctions. The clinicians are often given a task to estimate a patient's personality during treatment or during experts estimate of a drug addict. The aim of this research was to determine the differences, if any, in characteristics of addicts experience and personality traits in drug addicts with or without cerebral edema. Methods. The research was conducted on a sample of 252 male drug addicts, the average age of 23.3 (SD = 4.3) years. Cerebral edema was confirmed on magnetic resonance (MR) images of the brain performed during the treatment of the addicts. The participants were tested by the psychologists using Minnesota Multiphasic Personality Inventory (MMPI-201) test, and the data were processed using canonical discriminate analysis within the SPSS program. The dependent variable in the study was cerebral edema. A block of independent variables, designed for the requirements of this study, consisted of two subgroups. The first one consisted of 12 variables describing the relevant characteristics of drug abuse. The second subgroup consisted of 8 psychopathological tendencies in the personality defined by the mentioned test. Results. Cerebral edema was confirmed in 52 (20.63%) of the drug addicts. The differences between the groups of drug addicts with and without cerebral edema were determined in the following: the time span of taking drugs (0.301), use of alcohol parallel with drugs (0.466), and treatment for addiction (0.603). In the drug addicts with a cerebral edema, MMPI-201 confirmed the increase in the scales for hypochondria, psychopathic deviations and psychastenia, and the decrease in the scales for schizophrenia and depression. Conclusion. Our study confirmed a possible connection between cerebral edema and personality traits in a number of the examined drug addicts. Considering the fact that practice often requires personality estimation, regardless whether it is about treatment or expert's estimate, it is necessary to further research in this direction.Uvod/Cilj. Dejstvo droge ostavlja trajne posledice organskog tipa, na mozak, praćene brojnim neurološkim manifestacijama, i bitno utiče na razvoj psihičkih poremećaja. Kliničarima se često postavlja zadatak da procene ličnost tokom lečenja ili veštačenja zavisnika od droge. Cilj istraživanja bio je utvrđivanje karakteristika narkomanskog staža i osobina ličnosti kod zavisnika od droge sa i bez edema mozga. Metode. Istraživanje je sprovedeno u grupi od 252 zavisnika od droge muškog pola, prosečne starosti 23,3 (SD = 4,3) godine. Za vreme lečenja zavisnika od droge rađena je magnetna rezonanca mozga, a za procenu psihopatoloških tendencija ličnosti korišćen je Minnesota Multiphasic Personality Inventory (MMPI-201) test. Za obradu podataka korišćena je kanonička diskriminativna analiza u sklopu SPSS programa. Zavisna varijabla u istraživanju bio je edem mozga. Blok nezavisnih varijabli, sačinjen za potrebe ovog istraživanja, sastojao se od dve podgrupe. Prvu je činilo 12 varijabli kojima se opisuju relevantna obeležja zavisnosti od droga. Drugu je činilo 8 psihopatoloških tendencija ličnosti definisanih pomenutim testom. Rezultati. Edem mozga utvrđen je kod 52 (20,63%) zavisnika od droge. Razlike između grupa zavisnika od droge sa i bez edema mozga utvrđene su u dužini narkomanskog staža (0,301), korišćenju alkohola paralelno sa drogama (0,466) i lečenju zavisnosti (0,603). Kod zavisnika od droge sa cerebralnim edemom na MMPI-201 testu utvrđene su povišene skale hipohondrije, psihopatske devijacije i psihastenije, a sniženje skala šizofrenije i depresije. Zaključak. Kod jednog broja ispitivanih zavisnika od droge potvrđena je sumnja u mogućnost povezanosti edema mozga i osobina ličnosti. S obzirom na to da praksa često iziskuje potrebu za procenom ličnosti, bilo da se radi o lečenju ili veštačenju, neophodno je nastaviti istraživanja u ovom pravcu

HOW CAN SMALL-SCALE EVENTS CONTRIBUTE to the TOURISM PROGRESS of AN UNDEVELOPED BORDER AREA? LESSON from EASTERN SERBIA

The study analyses the role and impact of the event "Danube Fair" (Eastern Serbia) in the tourism progress of the less-advantaged border area. The aim of this paper is to emphasize the significance of the role of events in the tourism development of rural settings and the attraction of domestic and foreign visitors with the specific offer of this part of Serbia. The tourism valorization of the event “Danube Fair” was done according to the geographical and economic criteria, and it was determined that it belongs to the category of regional events. In the paper, special attention was paid to the analysis of tourists’ satisfaction with this event as a geographical criterion, especially in dependence with the visitors’ origin, since it is what the positioning of an event on the tourism market depends on, both on the local and on the international level. “Danube Fair” presents the example of a relatively small-scale event, which can become a basis of tourism growth, with proper valorization and affirmation of local products and services, and their introduction to the international tourism market. © 2020 Editura Universitatii din Oradea. All rights reserved.17-22-07001-ОГНAuthors would like to thank Russian Foundation for basic research for the financial support provided within the project No. 17-22-07001-ОГН (Complex algorithm for cultural regeneration of minor industrial cities within the context of agglomeration processes in Russia and Europe)

CCDC 2057269: Experimental Crystal Structure Determination. Crystallographic data for "Charge assisted assembly of zwitterionic pyridone hydrates"

UREZEZ : 4-methyl-6-oxo-5-(pyridin-1-ium-1-yl)-1,6-dihydropyridin-2-olate dihydrate Space Group: P 1 (2), Cell: a 7.2258(14)Å b 8.0470(16)Å c 11.287(2)Å, α 70.71(3)° β 74.88(3)° γ 79.85(3)°Crystallographic data (CCDC 2057269) for the article: Mašulović, A. D., Lađarević, J. M., Radovanović, L. D., Vitnik, Ž. J., Vitnik, V. D., Rogan, J. R.,& Mijin, D. Ž. (2021). Charge assisted assembly of zwitterionic pyridone hydrates. Journal of Molecular Structure, Elsevier., 1237, 130419. [https://doi.org/10.1016/j.molstruc.2021.130419]The published version of the article: [https://cer.ihtm.bg.ac.rs/handle/123456789/4506]The peer-reviewed version of the article: [https://cer.ihtm.bg.ac.rs/handle/123456789/4507]Supporting information: [https://cer.ihtm.bg.ac.rs/handle/123456789/4508]Related crystallographic data (CCDC 2057270): [https://cer.ihtm.bg.ac.rs/handle/123456789/4510

Complexes of d-block elements with aromatic o,o- and n,n-donor ligands: synthesis, structure, properties and applications

Reakcijom izmene liganada različitim metodama sinteze dobijeno je 22 ternarna kompleksa elemenata d-bloka [Mn(II), Co(II), Ni(II), Cu(II) i Zn(II)] sa anjonima aromatičnih polikarboksilnih kiselina (ftalne, izoftalne, tereftalne i piromelitne) kao O,O-donorskim ligandima i aromatičnim N,N-donorskim ligandima kao što su 2,2'-dipiridilamin i 2,2'-bipirimidin. Trinaest kompleksa sintetisano je u monokristalnom obliku, dok su ostala jedinjenja mikrokristalna. Prema vrsti centralnog atoma, u obliku monokristala dobijeno je pet Mn(II)-, dva Co(II)-, jedan Ni(II)-, dva Cu(II)-, dva Zn(II)-kompleksa, kao i bimetalni Mn(II)–Cu(II)-kompleks...A series of 22 d-block element complexes [Mn(II), Co(II), Ni(II), Cu(II) and Zn(II)] containing anions of aromatic polycarboxylate acids (phthalic, isophthalic, terephthalic and pyromellic) as O,O-donor ligands and aromatic N,N-donor ligands such as 2,2'-dipyridylamine and 2,2'-bipyrimidine, has been obtained by ligand exchange reaction using different synthetic methods. Thirteen complexes were obtained as single crystals, while the others were microcrystalline powders. According to the type of central atom, five Mn(II), two Co(II), one Ni(II), two Cu(II), two Zn(II) complexes, and bimetallic Mn(II)–Cu(II) complex were synthesized in form of single crystals. The structures of these compounds were determined by single-crystal X-ray analysis. Structural properties of complexes were discussed in detail and compared..

Somatic cell counts in bulk milk and their importance for milk processing

Bulk tank milk somatic cell counts are the indicator of the mammary gland health in the dairy herds and may be regarded as an indirect measure of milk quality. Elevated somatic cell counts are correlated with changes in milk composition The aim of this study was to assess the somatic cell counts that significantly affect the quality of milk and dairy products. We examined the somatic cell counts in bulk tank milk samples from 38 farms during the period of 6 months, from December to the May of the next year. The flow cytometry, Fossomatic was used for determination of somatic cell counts. In the same samples content of total proteins and lactose was determined by Milcoscan. Our results showed that average values for bulk tank milk samples were 273,605/ml from morning milking and 292,895/ml from evening milking. The average values for total proteins content from morning and evening milking are 3,31 and 3,34%, respectively. The average values for lactose content from morning and evening milking are 4,56 and 4,63%, respectively. The highest somatic cell count (516,000/ml) was detected in bulk tank milk sample from evening milk in the Winter and the lowest content of lactose was 4,46%. Our results showed that obtained values for bulk tank milk somatic cell counts did not significantly affected the content of total proteins and lactose