The modified drawing test for assessment of arm movement quality

The cerebrovascular accident often results in motor impairment of one of the upper limbs, hence, compromising the quality of life of stroke survivors. Rehabilitation aims to restore the movement abilities of the paralyzed/paretic upper limb. An important element in rehabilitation is to apply a quantified measure of the quality of movement, in order to follow the recovery and select the most appropriate therapeutic modality. We developed a method that uses data recorded during planar movements and outputs an objective measure that relates to the smoothness, velocity and precision of the movement. This method is universal, in a sense that hand position can be recorded by any available means (e.g., robot assistant, digitizing board, motion tracking systems, etc). The method follows the Drawing Test, but generates results that show the ability of the patient to make point to point movements and track the presented trajectory. The method is based on measurements of hand position during movement along a target path in form of a 2 cm wide rectangle. The patient's task is to move the hand along the target path as quickly as possible, with as few contacts (collisions) with the sides of the path. This paper addresses the aspects of automatic detection of parameters that quantify the quality of movement (speed, smoothness and precision). The use of this method is presented with 10 patients

Transport of silver nanoparticles from nanocomposite Ag/alginate hydrogels under conditions mimicking tissue implantation

The aim of this work was to assess phenomena occurring during AgNP transport from nanocomposite Ag/alginate hydrogels under conditions relevant for potential biomedical applications as antimicrobial soft tissue implants. First, we have studied AgNP migration from the nanocomposite to the adjacent alginate hydrogel mimicking soft tissue next to the implant. AgNP deposition was carried out by the initial burst release lasting for similar to 24 h yielding large aggregates on hydrogel surfaces and smaller clusters (similar to 400 nm in size) inside. However, the overall released content was low (0.67%) indicating high nanocomposite stability. In the next experimental series, release of AgNPs, 10-30 nm in size, from Ag/alginate microbeads in water was investigated under static conditions as well as under continuous perfusion mimicking vascularized tissues. Mathematical modeling has revealed AgNP release by diffusion under static conditions with the diffusion coefficient within the Ag/alginate hydrogel of 6.9x10(-19) m(2) s(-1). Conversely, continuous perfusion induced increased AgNP release by convection with the interstitial fluid velocity estimated as 4.6 nm s(-1). Overall, the obtained results indicated the influence of hydrodynamic conditions at the implantation site on silver release and potential implant functionality, which should be investigated at the experimentation beginning using appropriate in vitro systems

Eduard Sam in "Hourglass"

Ovaj rad ima za cilj da predstavi i sintetizuje biografske podatke jednog od glavnih likova romana Danila Kiša „Peščanik“, odnosno Eduarda Sema. Prvo ćemo navesti sve njegove lične podatke kao što su datum rođenja, adresa, bračno stanje, porodični odnosi, radno iskustvo, aktivnosti u slobodnom vremenu itd. Zatim ćemo predstaviti stepenike života i smrti onako kako se pojavljuju u romanu . Pošto je lik o kome je reč jevrejskog porekla, u radu će se ispitati ponavljajući znaci antisemitizma, kao i fizički i emocionalno oslabljujuće posledice takvog nacionalnog identiteta. Eduard Sem je neko ko je lucidan, a ne lud, a njegova lucidnost se pojavljuje kao rezultat njegovih neprekidnih spekulacija o teroru smrti u koncentracionom logoru.This paper aims to present and synthesize biographical data of one of the main characters in Danilo Kiš's novel "Hourglass", namely, Eduard Sam. First, we shall list all of his personal information such as the date of birth, address, marital status, family relations, work experience, pastime activities, etc. Then, we shall present the staircases of life and death as they appear within the novel. Since the character in question is of Jewish origin, the paper will examine the recurring signs of anti-Semitism as well as the physically and emotionally debilitating consequences of such national identity. Eduard Sam is someone who is lucid, not mad, with his lucidity emerging as a result of his ceaseless speculation about the terror of death within a concentration camp.Pod pokrovitelјstvom "Claims Conference ( Conference on Jewish Material Claims Against Germany)", Centar za studije sećanja Univerziteta u Kragujevcu - čiji je osnivač i rukovodilac prof. dr Katarina Melić - akademske 2021/2022. godine je dalekosežno pokrenuo Studije Holokausta. Jedan od realizovanih kurseva, "Istražni diskurs u književnosti" (prof. dr Dragan Bošković) održan je u zimskom semestru akademske 2021/2022. godine, i problemski je bio usredsređen na stvaralački opus Danila Kiša. Osim preispitivanja karaktera i smisla istražnog diskursa - elementarnog mehanizma epistemologije, naracije i poetike - glavna intencija kursa bila je analitičko percipiranje literarnih predstava Holokausta i antisemitizma u Kišovom delu, a kao jedan od rezultata rada na kursu bio je prezentacija Kišovih junaka-žrtava Holokausta. Tako su polaznici kursa izdvojili junake (likove-žrtve) iz "Porodičnog cirkusa", "Grobnice za Borisa Davidoviča", Kišovih drama i televizijske emisije "Goli život". Ispitujući (ili: oblikujući) njihove identitete, studenti su posebnu pažnju posvetili antisemitističkom belegu na njima, kao i njihovim tragičnim stradanjima. Uočivši simboličnu važnost realizovanih prezentacija, koje oslikavaju žrtve Holokausta u Kišovom opusu, došlo se na ideju preinačavanja power-point prezentacija u formu tekstova, i to tekstova nalik „ličnim kartama”. U želјi da sagledamo posledice Holokausta, kao i da predstavimo identitete žrtava i da čujemo njihov glas, tekstovi koji slede predstavlјaju omaž mrtvima - onima koji tek mogu da budu mrtvi onda kada progovore kroz literaturu, kroz diskurs. Progovorom kroz literaturu i kroz ove tekstove, mrtvi se samopotvrđuju kao žrtve, a tako i kao „besmrtni”. Stoga, ovaj temat - "Spomen-muzej žrtava Holokausta u opusu Danila Kiša" - prilog je narativnom otelotvorenju Kišovih žrtava koje, kako bi to rekao Pol Riker, „vape za odmazdom i prizivaju priču”. Ovaj mali tematski blok je, dakle, njihova i naša „odmazda”, njihova i naša „priča”. Ovaj tekst je jedan od šest tekstova čiji su autori doktorandi Filološko-umetničkog fakulteta Univerziteta u Kragujevcu, i ovo su prvi tekstovi ovakvog tipa u celokupnoj istoriji kišologije. O likovima-žrtvama Holokausta dati su uvidi u formi taksativno navedenih biografskih informacija, dok je posebna pažnja posvećena antisemitizmu i to u odelјku svakog teksta, naslovlјenom: „Znakovi i posledice antisemitizma/Holokausta”.Sponsored by "Claims Conference (Conference on Jewish Material Claims Against Germany"), the Centre for the Study of Memory of the University of Kragujevac - whose founder and the head is prof. Katarina Melić, PhD, full professor - has, during the academic year of 2021/2022, issued forth the Holocaust Studies. One of the realized courses, "Investigative Discourse in Literature" (prof. Dragan Bošković, PhD, full professor) was held in the winter semester of the academic year of 2021/2022 and was focused on the creative work of Danilo Kiš through a problem-solving approach. Apart from re-examining the character and meaning of investigative discourse - the elementary mechanism of epistemology, narration and poetics - analytical perception of literary representations of the Holocaust and antisemitism in Kiš’s work represented the primary intention of the course, and one of the results of course activities was the presentation of Kiš’s characters-victims of the Holocaust. Thus, the attendees of the course sought to single out the heroes (characters-victims) from the "Family Circus", "A Tomb for Boris Davidovich", Kiš’s plays and the television show "Naked Life". Examining (or: shaping) their identities, the students paid special attention to the antisemitic mark on them, as well as their tragic sufferings. Having noticed the symbolic significance of the completed presentations, while concurrently depicting the victims of the Holocaust in Kiš’s oeuvre, there emerged an idea to transform power-point presentations into the form of manuscripts, and not just any, but manuscripts similar to “identity cards”. In order to appreciate the consequences of the Holocaust, as well as to present the identities of the victims and hear their voices, the following manuscripts represent a homage to the dead - to those who may be dead only after they have spoken through literature, through discourse. By speaking through literature and through these manuscripts, the dead assert themselves as victims, and thus as “immortals”. Therefore, this thematic issue - "The Memorial Museum of the Holocaust Victims in the Oeuvre of Danilo Kiš" - constitutes a contribution to the narrative embodiment of Kiš’s victims who, as Paul Ricoeur would say, “cry out for retribution and invoke a story”. This small-scale thematic issue is, hence, their and our “retribution”, their and our “story”. This is one of six manuscripts whose authors are PhD students at the Faculty of Philology and Arts, University of Kragujevac, and these are the first manuscripts of this type in the entire history of Kišology. Insights into the characters-victims of the Holocaust are provided in the form of exhaustive specifications of biographical information, paying special attention to antisemitism in a particular section of each manuscript, entitled: „Signs and Consequences of Antisemitism/Holocaust”

Ekstrakcija ulja iz semena konoplje (Cannabis sativa L.) i njegova primena u sintezi biodizela

The subject of this doctoral dissertation research was to obtain the oil from hemp seeds and to use it for biodiesel production. The main goals of the dissertation were optimization of operating conditions, kinetics modeling and thermodynamic analysis of maceration process, as well as optimization and modeling of hempseed oil methanolysis reaction kinetics. In order to determine the dependence of oil yield on process conditions process conditions and modeling the hempseed oil maceration, the response surface methodology (RSM) in combination with 33 full factorial design with replication, as well as artificial neural network combined with genetic algorithm (ANN-GA) were used. The variance analysis (ANOVA) revealed that extraction temperature had the greatest influence on the hempseed oil yield, followed by seed:solvent ratio and extraction time. Optimal extraction conditions determined by RSM (extraction temperature 70 oC, seed:solvent ratio 1:7.9 g/ml and 12.3 min extraction time) and ANN-GA methods (extraction temperature 70 oC, seed:solvent ratio 1:10 g/ml and 10 min extraction time) were very close. The predicted oil yield values determined by second-order polynomial equation and neural network model agreed very well with experimentally obtained values, so both models are acceptable for oil yield prediction in the investigated extraction conditions range. The two kinetic models were used for modeling the kinetics of hempseed oil maceration: simultaneous washing and diffusion (phenomenological model) and instantaneous washing followed by diffusion (simplified phenomenological model). In both cases, good agreement between the predicted and actual hempseed oil yields was obtained, indicated by low mean MRPD (±2.5% in the case of a phenomenological model and ±2.8% in the case of a simplified model). The thermodynamic analysis results of the hempseed oil extraction have shown that the oil extraction was spontaneous, endothermic and irreversible. For the biodiesel production, hempseed oil was obtained by seed pressing. As the free fatty acids (FFAs) content in the oil was higher than 2%, the synthesis of fatty acid methyl esters (FAMEs) was carried out by a two-stage process including acid-catalyzed esterification of FFAs in the oil followed by base-catalyzed methanolysis of esterified oil. The methanolysis reaction was carried out in the presence of quicklime as a catalyst, at different methanol:oil molar ratios and various amounts of catalyst. According to the ANOVA results, catalyst concentration, reaction time, interaction of the catalyst concentration and reaction time, as well as the square of reaction time had statistically significant influence on the FAMEs content of hempseed oil, while the effects of methanol:oil molar ratio, its interaction with the two other factors as well as squares of methanol:oil molar ratio and catalyst concentration, were statistically insignificant. The reliability of the model in predicting the FAMEs content was confirmed by appropriate statistical criteria and low MRPD value. The irreversible pseudo-first order kinetic model and model that included the changing mechanism of the reaction and the triacylglycerols mass transfer limitation were applied for modeling the methanolysis reaction kinetics of esterified hempseed oil. The catalyst concentration and the initial methanol concentration had no effect on the apparent rate constant of esterified oil methanolysis reaction, and its value, determined using both kinetic models, was 0.141 min-1. Both kinetic models are reliable in presenting a change in the triacylglycerol conversion degree, but the irreversible pseudo-first-order reaction model is more acceptable because it has a slightly lower MRPD value between the predicted and actual values of FAMEs content

Snabdevenost važnijih tipova zemljišta Srbije osnovnim alkalnim elementima Ca, Mg, K i Na

In this paper results are presented of agrochemical and mineralogical analyses of 14 types of important soils in Serbia (Vojvodina and Central Serbia) and total content and availability of base alkali elements (Ca, Mg Na, K) are determined. Total element content was as follows: Ca 2.22%; K 1.77%; Na 0.85% and Mg 0.61%. Total content of alkali metals in the soils investigated and their variations within and between the soil types, is in very good/close correlation with contents of primary and secondary minerals as well as their rates of weathering. Taking in account the average availabilities the most abundant is calcium with 947 mg/100 g, whilst the averages of the other elements (Mg, K and Na) are quite similar and are about of 40 mg/100 g of soil. The results obtained have shown that the soils investigated are well to moderate provided with K, Ca and Mg and that their deficit could not be expected in plant nutrition, apart for some plants/cultures in the case of magnesium due to occasionally higher Ca/Mg and K/Mg ratios.U ovom radu je ispitivano 100 reprezentativnih uzoraka 14 tipova zemljišta Srbije (Vojvodina, Šumadija i Severno Pomoravlje) u pogledu ukupnog i pristupačnog sadržaja osnovnih alkalnih metala (Ca, Mg, K i Na). Takođe je prikazan i prosečan mineraloški sastav ispitivanih zemljišta. Nađeni su sledeći srednji ukupni sadržaji ispitivanih elemenata: Ca - 2,25%; K - 1,77% Na - 0,85% i Mg - 0,61%. Ukupni sadržaji ispitivanih alkalnih metala u našim zemljištima i njihova vapipanja između i unutar zemljišnih tipova u uskoj su vezi sa zastupljenošću određenih primarnih i sekundarnih minerala i njihovom otpornošću na raspadanje. Prema srednjim vrednostima za pristupačne sadržaje najviše ima kalcijuma (947 mg/100 g), a srednji sadržaji za ostale baze (Mg K i Na) su vrlo slični i kreću ce oko 40 mg/100 g. Dobijeni rezultati pokazuju da su ispitivana zemljišta dobro i srednje obezbeđena K, Ca i Mg i da se ne mogu očekivati njihovi deficiti za ishranu biljaka, osim za neke kulture u slučaju magnezijuma, zbog ponekad suviše povišenih odnosa Ca/Mg i K/Mg

Rock’n’roll and Holocaust

„Rock’n’roll i Holokaust”, tekst u kome se sve već dogodilo, ali i u kome se sve tek treba dogoditi, budući da živimo u „odsustvu svake prave prisutnosti” (Džejmson 1974: 145), ima želju, ma koliko ona bila neostvariva, da se "oslobod[i] od obaveze započinjanja” (Fuko 2019: 7). On, međutim, ipak mora „započeti” i pokušati da, u nekom jeziku i diskursu, kaže nešto o ideologijama, Holokaustu i rock’n’roll-u: Belsen was a Gas Sex Pistols-a, Puppets Lenarda Koena, No Love Lost Joy Division-a.“Rock’n’roll and Holocaust” represents, on one hand, a text in which everything has already happened and, on the other, a text in which everything is yet to happen because we, if we are to believe Jameson, live in the absence of any true presence. Moreover, this paper has a Focauldian desire to liberate itself from the obligation of commencing. It, however, has to “commence” and, with some language and discourse, attempt to say something about ideologies, Holocaust and rock-n-roll: Sex Pistols’ Belsen was a Gas, Leonard Cohen’s Puppets, Joy Division's No Love Lost.Istraživanje sprovedeno u radu finansiralo je Ministarstvo prosvete, nauke i tehnološkog razvoja Republike Srbije (Ugovor o realizaciji i finansiranju naučnoistraživačkog rada NIO u 2022. godini broj 451 -03-68/2022 14/ 200198)

Razvoj numeričkih modela za efikasnu kakaterizaciju disperzivnih i generalnih anizotropnih elektromagnetskih struktura u mikrotalasnom opsegu frekvencija

In the dissertation, two methods for the realization and implementation of compact numerical models are presented using the TLM (Transmission Line Matrix) method based on Z-transformation techniques for the modeling of dispersive and general anisotropic electromagnetic structures in the microwave frequency range. The formulation of the Z-TLM method has been extended to cover the general case of a numerical network based on nonuniform spatial discretization. The first method was developed in response to the problem of modeling geometrically small, but from an electromagnetic viewpoint of important, dispersive and generally anisotropic electromagnetic structures, by using conventional methods based on the use of a fine resolution network, being highly demanding regarding computer resources. Within this method, the structure is modeled by the introduction of an appropriate interface between the neighboring TLM nodes that simulates the exchange of voltage impulses in the same way as the structure is present in the numerical network, which is convenient in cases where the direct behavior of the electromagnetic field within the structure is not important for analysis. This significantly reduces amount of required memory and processor resources, as well as the duration of the simulation, where the necessary number of nodes in the numerical network can be reduced for more than 90% in some cases. Second presented method provides the possibility that dispersive and generally anisotropic structures, characterized only by the scattering matrix, are introduced into a numerical simulation in order to analyze the effects of the propagation and distribution of the electromagnetic field within these structures. Modeling is done using the effective electromagnetic parameters calculated by applying the appropriate retrieval method to the scattering matrix coefficients of the modeled structure, which can be obtained by experimental measurement, analytical approach, or using one of the reliable methods of electromagnetic simulation. This method opens the possibility for a potential analysis of the effect of changing the effective parameters on the distribution of the electromagnetic field for optimization of the existing and development of new components and devices based on generally anisotropic and dispersive materials such as antennas and filters. The developed methods are implemented into a non-commercial solver using the higher-level programming language - MATLAB in order to numerically simulate dispersive and generally anisotropic materials in the time domain. The efficiency and reliability of both methods are verified and illustrated on examples of thin panels of carbon fiber composites, metamaterials and chiral material

Kinetics and mechanism of silver release from nanocomposite Ag/alginate hydrogels for different applications

Nanokompoziti na bazi alginatnih hidrogelova sa nanočesticama srebra su atraktivni za primenu u medicini, i to kao antimikrobne obloge za rane i implantati za meka tkiva. Ovi nanokompoziti omogućavaju stabilizaciju i kontrolisano otpuštanje nanočestica i/ili jona srebra dok sam hidrogel obezbeđuje hidrofilnu, biokompatibilnu sredinu. Pored toga, atraktivni su i za primenu kao komponente funkcionalnih pakovanja za hranu gde bi mogli da obezbede antimikrobno dejstvo i time, i produženi vek trajanja hrane. Prema tome, funkcionalnost Ag/alginatnih nanokompozitnih hidrogelova u velikoj meri zavisi od načina i brzine otpuštanja srebra. Pored toga, poznavanje mehanizma i kinetike otpuštanja nanočestica i/ili jona srebra je krucijalno i sa stanovišta utvrđivanja uticaja ovih nanokompozita na ljudski organizam i životnu sredinu prilikom upotrebe. Cilj istraživanja u ovoj doktorskoj disertaciji je bio razvoj matematičkih modela koji bi opisali mehanizam i kinetiku otpuštanja nanočestica i/ili jona srebra iz nanokompozitnih alginatnih hidrogelova radi postizanja antimikrobne aktivnosti u različitim primenama. Shodno tome, fokus je stavljen na hidrogelove sa elektrohemijski sintetisanim nanočesticama srebra za potencijalnu primenu u medicini, kao i na razvoj i karakterizaciju kompozitnih polimernih filmova sa alginatnim mikročesticama sa sadržanim nanočesticama srebra sintetisanim hidrotermalnom metodom za primenu u pakovanju hrane. Primenom obe navedene metode u rastvoru natrijum-alginata uspešno su sintetisane sferične nanočestice srebra u opsegu veličina od 4 – 30 nm dajući stabilne Ag/alginatne koloidne rastvore. Ovi rastvori su dalje bili pogodni za dobijanje hidrogelova u različitim oblicima tako da su izlivanjem dobijeni nanokompozitni diskovi, a elektrostatičkom ekstruzijom nanokompozitne mikročestice. Hidrogelovi sa elektrohemijski sintetisanim nanočesticama su zatim ispitivani u pogledu kinetike otpuštanja nanočestica i/ili jona srebra pri različitim hidrodinamičkim uslovima relevantnim za primenu u medicini. Statički uslovi i direktan kontakt dva hidrogela su imitirali obloge za rane i implantate u neprokrvljenim tkivima dok su ipitivanja pri kontinualnom protoku fluida imitirala implantaciju u vaskularizovana tkiva. Posebno su ii izvedeni eksperimenti u vodi i fiziološkom rastvoru kao modelu bioloških fluida. Na osnovu eksperimentalnih ispitivanja su zatim razvijeni i uspešno primenjeni matematički modeli koji su uključili difuziju nanočestica srebra kroz alginatnu matricu, reakciju oksidacije nanočestica i reakciju sa jonima hlora iz rastvora, i, najzad, difuziju nagrađenih formi AgClx (x-1)-. Dobijeni su veoma niski koeficijenti dufuzije nanočestica srebra iz vlažnih Ag/alginatnih mikročestica u vodi reda veličine ~ 10-18 m2 s-1 što ukazuje na dobru stabilizaciju nanočestica srebra u alginatnoj matrici. U direktnom kontaktu sa alginatnim hidrogelom u statičkim uslovima, mala količina (~ 0,7 %) nanočestica je migrirala stvarajući veće agregate na površini hidrogela i više manjih agregata (~ 400 nm) unutar hidrogela. Sa druge strane, kontinualni protok vode kroz pakovani sloj Ag/alginatnih mikročestica je izazvao nekoliko puta veće otpuštanje srebra izazvano spiranjem nanočestica intersticijalnom brzinom fluida unutar mikročestica koja je određena kao ~ 5 nm s-1. Matematičko modelovanje otpuštanja srebra iz Ag/alginatnih mikročestica u fiziološkom rastvoru je ukazalo na oksidaciju nanočestica kinetikom prvog reda sa konstantom brzine reda veličine ~ 10-6 s-1. Pri tome je brzina oksidacije i reakcije sa jonima hlora rasla sa brzinom prenosa mase ovih jona tako da je bila najveća u slučaju suvih Ag/alginatnih mikročestica u kojima je tokom bubrenja ostvaren konvektivni prenos. Shodno tome, brzina difuzije nagrađenih AgClx (x- 1)-1 formi u tom slučaju je bila i najmanja ukazujući da je najverovatnije većim delom formiran precipitat AgCl...Nanocomposite alginate hydrogels with incorporated silver nanoparticles are attractive for medical applications such as antimicrobial wound dressings and soft tissue implants. These nanocomposites provide stabilization and controlled release of silver nanoparticles and/or ions while the hydrogel itself, provides a hydrophilic and biocompatible environment. In addition, Ag/alginate nanocomposites are attractive for applications as components of functional food packaging due to antimicrobial effects that prolong food freshness. Thus, the functionality of Ag/alginate nanocomposite hydrogels largely depends on the rate and route of silver release. Furthermore, understanding the kinetics and mechanism of silver nanoparticle and/or ion release is crucial from the point of assessing the effects on human tissues and the body as well as on the environment during the nanocomposite use. The aim of this doctoral thesis was to develop mathematical models describing mechanisms and kinetics of silver nanoparticle and/or ion release from nanocomposite Ag/alginate hydrogels designed to achieve antimicrobial activity in different applications. The focus was on Ag/alginate hydrogels with electrochemically synthesized silver nanoparticles for potential applications in medicine, as well as on development and characterization of composite polymer films containing Ag/alginate microbeads with silver nanoparticles synthesized by a hydrothermal method for applications in food packaging. Utilization of both synthesis methods in Na-alginate solutions resulted in spherical silver nanoparticles in the size range 4 – 30 nm yielding stable Ag/alginate colloid solutions. The solutions were suitable for production of hydrogels in different forms such as discs produced by decanting and gelation as well as microbeads obtained by electrostatic extrusion. Hydrogels with electrochemically synthesized silver nanoparticles were investigated next regarding the release kinetics of silver nanoparticles and/or ions under different hydrodynamic conditions relevant for medical applications. Static conditions and a direct contact of a nanocomposite and an alginate hydrogel were set to mimic wound dressings and implants in nonvascularized tissues v while the studies under continuous fluid perfusion imitated implants in vascularized tissue sites. In addition, the experiments were performed in water and physiological saline solution as a model of biological fluids. Based on the experimental results mathematical models were derived, which included diffusion of nanoparticles within the alginate hydrogel, nanoparticle oxidation and reaction with chloride ions present in the saline solution, and finally, diffusion of formed AgClx (x-1)- species..