Analysis of input-to-state stability for discrete time nonlinear systems via dynamic programming

The input-to-state stability (ISS) property for systems with disturbances has received considerable attention over the past decade or so, with many applications and characterizations reported in the literature. The main purpose of this paper is to present analysis results for ISS that utilize dynamic programming techniques to characterize minimal ISS gains and transient bounds. These characterizations naturally lead to computable necessary and sufficient conditions for ISS. Our results make a connection between ISS and optimization problems in nonlinear dissipative systems theory (including L2-gain analysis and nonlinear H∞ theory). As such, the results presented address an obvious gap in the literature. © 2005 Elsevier Ltd. All rights reserved

A unified approach to controller design for achieving ISS and related properties

A unified approach to the design of controllers achieving various specified input-to-state stability (ISS) like properties is presented. Both full state and measurement feedback cases are considered. Synthesis procedures based on dynamic programming are given using the recently developed results on controller synthesis to achieve uniform l∞ bound. Our results provide a link between the ISS literature and the nonlinear H∞ design literature. © 2005 IEEE

Evaluacija genotoksičnih efekata tiroksina primenom in vivo citogenetičkog testa na Swiss albino miševima

Thyroid hormones enhance aerobic metabolism favoring oxidative stress which may lead to covalent damage of various molecules including DNA. Previous investigations revealed that thyroid hormones induce DNA damage on human lymphocytes and sperm in the in vitro Comet assay. However, cytogenetic evaluation of genotoxic effects of thyroxine gave equivocal results: increase of sister chromatid exchanges, and no incerase of micronuclei in cultured human lymphocytes. Therefore, the aim of the present study was to further evaluate the possible genotoxic effects of thyroxine using in vivo cytogenetic test on Swiss albino mice. Three experimental concentrations of thyroxine were used (0.1 mg/kg, 0.5 mg/kg and 2.5 mg/kg). The mice were divided into several groups depending on the duration of the treatment with thyroxine. Thus, we treated mice for 1, 3, 7 and 10 days. Positive (Nmethyl- N'-nitro-N-nitrosoguanidine) and negative controls were also formed for the same time periods. Cytogenetic endpoinds (numerical and structural aberrations, chormosome gaps and breaks) were analysed in bone marrow cells from femures. The results obtained in this investigation showed that thyroxine has not induced chromosome damage or aberrations. This is in agreement with our previous analysis of micronuclei in human peripheral blood lymophocytes treated with thyroxine. On the other hand, we observed a decrease of mitotic index especially in animals treated for a longer period of time with the highest dose of thyroxine. Therefore, it can be concluded that thyroxine does not induce genotoxic effects which could be detected by cytogenetic analysis.Tireoidni hormoni podstiču aerobni metabolizam favorizujući oksidativni stres koji može da dovede do kovalentnih oštećenja različitih molekula uključujući i DNK. U prethodnim istraživanjima otkriveno je da tireoidni hormoni indukuju oštećenja molekula DNK u humanim limfocitima i spermi u in vitro Komet testu. Međutim, citogenetička evaluacija genotoksičnih efekata tiroksina dala je kontradiktorne rezultate: povećanje razmena sestrinskih hromatida bez porasta učesalosti mikronukleusa u kulturama humanih limfocita. Stoga je cilj istraživanja u ovom radu bio da dodatno ispitamo moguće genotoksične efekte tiroksina koristeć i in vitro citogenetički test na Swiss albino miševima. Upotrebljene su tri eksperimentalne koncentracije tiroksina (0,1 mg/kg, 0,5 mg/kg and 2.5 mg/kg). Miševi su podeljeni u nekoliko grupa zavisno od dužine tretmana tiroksinom: 1, 3, 7 i 10 dana. U istim vremenskim periodima miševi su tretirani pozitivnom (N-metil-N'-nitro-N-nitrozogvanidin) i negativnom kontrolom. Analizirani su citogenetički parametri (numeričke i strukturne aberacije hromozoma, gapovi i prekidi na hromozomima) u ćelijama kostne srži izolovanim iz femura. Rezultati dobijeni u ovom istraživanju ukazuju da tiroksin ne indukuje hromozomske prekide i aberacije, što je u saglasnosti sa našim prethodnim zapažanjima na humanim limfocitima u kulturi. Istovremeno, primetili smo smanjenje mitotskog indeksa, naročito kod životinja tretiranih u dužem vremenskom periodu sa visokim dozama tiroksina. Prema tome, može se zaključiti da tiroksin ne indukuje genotoksične efekte koji mogu da se detektuju citogenetičkim analizama

Measurement feedback controller design to achieve input to state stability

An approach for design of measurement feedback controllers achieving input-to-state (ISS) stability properties is presented. A synthesis procedure based on dynamic programming is given. We make use of recently developed results on controller synthesis to achieve uniform l∞ bound [6]. Our results make an important connection between the ISS literature and nonlinear H∞ design methods

The importance of comorbidity on the survival of patients with laryngeal squamous cell carcinoma

Uvod: Komorbiditeti su bolesti ili stanja koja postoje pored glavnog oboljenja. Komorbidne bolesti mogu da utiču na izbor lečenja, kao i na stopu preživljavanja. Instrumenti za procenu komorbiditeta mogu biti: opšti - mere stepen komorbiditeta kod različitih oboljenja npr. Čarlsonov indeks komorbiditeta (Charlson Comorbidity Index ili CCI) i specifični - mere stepen komorbiditeta kod određenog oboljenja npr. Procena komorbiditeta kod odraslih-27 indeks (Adult Comorbidity Evaluation-27 index ili ACE-27 index). Ciljevi rada su: Ispitati značaj komorbiditeta za preživljavanje bolesnika s planocelularnim karcinomom larinksa pomoću CCI i ACE-27 indeksa; Odrediti da li postoji razlika u učestalosti javljanja komorbiditeta i u dužini preživljavanja između bolesnika s planocelularnim karcinomom supraglotisa u odnosu na bolesnike s karcinomom glotisa; Ispitati značaj opšteg (CCI) i specifičnog (ACE-27) indeksa u proceni preživljavanja bolesnika s planocelularnim karcinomom larinksa. Materijal i metode: U studiju je uključeno 177 novoobolelih od planocelularnog karcinoma larinksa (T1-T4) koji su lečeni hirurški ili hirurški u kombinaciji s postoperacionom radioterapijom u Klinici za otorinolaringologiju i maksilofacijalnu hirurgiju Kliničkog centra Srbije u periodu od 1.1.2000. do 31.12.2003. godine. Podaci o bolesnicima su prikupljeni iz istorija bolesti, patohistoloških izveštaja i registra za maligna oboljenja. U statističkoj analizi podataka korišćena je krivulja preživljavanja prema Kaplanu i Mejeru (Meier), log-rank test, Koksov (Cox) proporcionalni hazardni model, Man-Vitnijev (Mann-Whitney) test i Kruskal-Volisov (Kruskal-Wallis) test. Rezultati: Prema CCI, 40,1% (71) bolesnika s planocelularnim karcinomom larinksa je imalo komorbidne bolesti od kojih su najčešće bile kardiovaskularne (40,3%), respiratorne (27,8%) i gastrointestinalne (14,4%). Međutim, prema ACE-27 indeksu, 66,7% (118) bolesnika s planocelularnim karcinomom je imalo komorbidne bolesti a najčešće su bile kardiovaskularne (53,1%), respiratorne (15,6%) i gastrointestinalne (8,8%). Skoro svaki četvrti oboleli je imao dve ili više komorbidnih bolesti prema CCI, kao i prema ACE-27 indeksu...Introduction: Comorbidities are diseases or conditions that coexist with the disease of interest. Comorbid diseases can influence the treatment of choice as well as the rate of survival. Comorbidity assessment instruments can be: general - measure the burden of comorbidity across a wide range of index conditions (the Charlson Comorbidity Index or CCI) and specific - measure the overall severity of comorbidity for a particular index disease (the Adult Comorbidity Evaluation-27 or ACE-27 index). Objectives: To examine the importance of comorbidity in the survival of patients with squamous cell carcinoma of the larynx using CCI and ACE-27 index, to determine whether there is a difference in the frequency of comorbidity and survival in patients with squamous cell carcinoma of the supraglottis than patients with glottic cancer, and to examine the importance of general (CCI) and specific (ACE-27) index to estimate survival of patients with squamous cell carcinoma of the larynx. Material and Methods: The study included 177 new cases of squamous cell carcinoma of the larynx (T1-T4) that were treated by surgery only or in combination with surgery and postoperative radiotherapy at the Clinic of Otorhinolaryngology and Maxillofacial Surgery, Clinical Centre of Serbia between 1 January 2000 and 31 December 2003. The study data were obtained from medical records, pathology reports, and tumour registry abstracts. For the statistical analysis of data the Kaplan-Meier survival analysis, the log-rank test, the Cox proportional hazards regression model, the Mann-Whitney and the Kruskal-Wallis tests were used. Results: According to the CCI, 40.1% (71) patients with laryngeal squamous cell carcinoma had comorbid diseases. The most frequent comorbid ailments were related to the cardiovascular (40.3%), respiratory (27.8%) and gastrointestinal systems (14.4%). However when using the ACE-27 index it was found that 66.7% (118) had these same diseases..

Genome variability of Human Parvovirus B19 (Parvoviridae, Erythrovirus)

Uvod: Infekcija parvoB19 virusom koja se prenosi respiratornim i vertikalnim putem, ali i preko zaražene krvi i krvnih derivata, može predstavljati ozbiljan zdravstveni problem za rizične grupe pacijenata. Ovaj, po dimenzijama mali DNK virus bez omotača je vrlo otporan na standardne tehnike inaktivacije virusa u proizvodnji derivata krvi, a pouzdanu dijagnostiku otežava varijabilnost genomske sekvence virusa. Određivanje karakteristika nukleotidnih sekvenci izolata B19 virusa od značaja je za razvoj dijagnostičkih metoda i daje uvid u puteve nastanka i održavanja genomske varijabilnosti B19 virusa. Cilj ovog rada bio je da se odredi učestalost B19 virusa kod dobrovoljnih davalaca krvi i kod pacijenata sa sumnjom na B19 infekciju i da se na osnovu molekularno genetskih karakteristika dobijenih genomskih sekvenci, a u poređenju sa genomskim sekvencama dostupnim u bazama podataka, odredi evolutivna dinamika varijabilnosti parvoB19 virusa i filogenetski i filogeografski odnosi ispitivanih B19 izolata. Metode: Uzorci plazme dobrovoljnih davalaca i plazme i krvi pacijenata sa sumnjom na B19 infekciju analizirani su na prisustvo B19 DNK primenom lančane reakcije polimeraze (PCR), kako metodama iz literature tako i razvijenom internom metodom. Za uzorke sa detektovanim B19 genomom, direktnim nukleotidnim sekvenciranjem određena je genomska sekvenca. Bioinformatičkom analizom u odnosu na genomske sekvence B19 virusa dostupne u bazama podataka određen je genotip izolovanih virusnih genoma, evolutivni pritisci na osnovu odnosa nesinonimnih i sinonimnih zamena (dN/dS) za nukleotidne sekvence koje kodiraju virusne proteine, kao i genetičke distance i filogenetski odnosi B19 izolata dobijenih u Srbiji u odnosu na izolate iz drugih geografskih regija. Rezultati: Za 5 izolata iz Srbije, utvrđena je sekvenca B19 genoma u regiji kompletne cDNK. Iz baze podataka izdvojeni su i analizirani izolati sa poznatom sekvencom u regiji kompletne ili skoro kompletne cDNK, kojih je do 2012. godine bilo ukupno 146, od toga 117 genotipa 1. Analizom odnosa dN/dS za virusne proteine na osnovu većeg broja nukleotidnih sekvenci u odnosu na dosadašnje literaturne podatke procenjen je uticaj pozitivne i negativne selekcije na varijabilnost virusnog genoma...Abstract: Background: Parvovirus B19 infection, being transmitted via the respiratory route, vertically from mother to fetus as well as through blood-derived products administered parenterally, can represent a serious health problem for risk patients groups. This small non-enveloped DNA virus is extremely resistant to standard viral inactivation techniques, while a reliable diagnosis is challenged by the virus genome sequence variability. Characterization of B19 isolates nucleotide sequences is valuable for development of diagnostic methods, and it gives an insight into the genesis and maintenance of the B19 virus genome variability. Aim of this thesis was to determine the frequency of B19 viremia in voluntary blood donors and in patients with the B19 infection symptoms, investigate the level and evolutionary dynamics of the B19 genome variability as well as to examine phylogenetic and phylogeographic relations of the B19 genomes obtained in Serbia with the isolates from the other parts of the world on the bases of the almost complete B19 cDNA sequences. Methods: Plasma samples of the voluntary blood donors, and plasma and blood samples of the B19 infection suspected patients were analysed for the B19 DNA presence by the polymerase chain reaction (PCR), using the methods described in the literature as well as internally developed method. For the B19 genome positive samples genome sequences were determined by direct sequencing. Bioinformatic analysis was performed by using the generated data as well as the database information in order to determine a genotype of the isolated genomes, evolutionary pressures (based on dN/dS ratio) for virus protein coding sequences, and genetic distances and phylogenetic relations of the B19 isolates from Serbia compared to the other geographic regions. Results: For 5 isolates from Serbia, the B19 genome sequence was determined for the complete cDNA. Database isolates with the known, complete or almost complete cDNA, available until the end of 2012 (146 isolates in total, out of which 117 were genotype 1) were chosen and used for the analysis. Positive and negative selection influence for the virus protein coding sequences was determined by the dN/dS ratio analysis by using larger data set than described in the literature so far..

p-Adic and Adelic Free Relativistic Particle

We consider spectral problem for a free relativistic particle in p-adic and adelic quantum mechanics. In particular, we found p-adic and adelic eigenfunctions. Within adelic approach there exist quantum states that exhibit discrete structure of spacetime at the Planck scale.Comment: 9 page

Korelaciona povezanost telesne mase srpske bele koze prema tipu jarenja i proizvodnim osobinama

Main breeding objective in improvement of goat production is realization of increase of number of animals and production and creation of constant highly productive goat breeding on private farms of individual producers. For economically efficient goat production, size and number of goats in the herd are of great importance. Considering that goats of greater body mass should realize higher production, body mass of head can serve as one of the parameters in selection. Objective of this research was to determine optimal body masses of heads in population of Serbian White goat, in hilly-mountainous region of Stara Planina Mountain, in semiintensive rearing system (pasture-stable) and in relation to realized production. Based on results of research it can be concluded that optimal body mass of investigated heads in population of Serbian White goat in regard to observed parameters of production is between 40-47 kg.Osnovni odgajivački cilj u poboljšanju kozarske proizvodnje je povećanje broja životinja i povećanje proizvodnje, odnosno stvaranje stalnog visokoproduktivnog kozarstva na farmama individualnih odgajivača. Za ekonomičnu kozarsku proizvodnju od velike važnosti je veličina grla i brojnost koza u stadu. Polazeći od činjenice da koze sa većom telesnom masom treba da ostvare i veću proizvodnju, to masa tela grla može da posluži i kao jedan od parametara u selekciji. Cilj ovih istraživanja je da se utvrde optimalne telesne mase grla u populaciji srpske bele koze, u brdskoplaninskom području Stare Planine, u poluintenzivnom sistemu gajenja (pašno-stajski) i u odnosu na ostvarenu proizvodnju. Na osnovu rezultata sprovedenih istraživanja može se zaključiti da je optimalna telesna masa ispitivanih grla u populaciji srpske bele koze u odnosu na posmatrane parametre proizvodnje između 40-47 kg

Determination of phase wetting in oil-water pipe flows

Oil-water two-phase flow is often a problem in transportation since the corrosion rate is closely related to which phase wets the pipe. The problem has been investigated on a large scale, in a 60 meter-long flow loop with Saudi Arabian crude oils. In this paper extensive experimental studies of flow pattern as well as phase wetting determination have been carried out for different crude oils and different pipe inclinations. Four experimental techniques have been applied to determine which phase, either water or oil, wets the pipe inner wall at different flowing conditions: wall conductance probes, wall sampling, flow visualization, and corrosion monitoring by electric resistance probes. Based on the overlapping information from these techniques, comprehensive phase wetting maps as a function of water cut and flow velocities were obtained. Three flow patterns were observed: stratified flow, stratified flow with mixed layer, and dispersed flows. The comparison of flow pattern and wetting regimes gives good understanding of the water wetting mechanism. Moreover, the phase wetting maps produced are a precious tool which can be used as a useful reference for corrosion engineers and pipeline operators to manipulate oil-water two-phase flow systems under corrosion free conditions

Event-triggered transmission for linear control over communication channels

We consider an exponentially stable closed loop interconnection of a continuous linear plant and a continuous linear controller, and we study the problem of interconnecting the plant output to the controller input through a digital channel. We propose a family of "transmission-lazy" sensors whose goal is to transmit the measured plant output information as little as possible while preserving closed-loop stability. In particular, we propose two transmission policies, providing conditions on the transmission parameters. These guarantee global asymptotic stability when the plant state is available or when an estimate of the state is available (provided by a classical continuous linear observer). Moreover, under a specific condition, they guarantee global exponential stabilit