88 research outputs found
The maximal number of U-k - seminets of the maximal degree
Aczel (1965) investigated quasigroups, 3-nets and nomograms
and Belousov (1971) k-nets and associated (k-1) - quasigroups. There are different 3 - seminets and k-seminets (see e.g. Havel (1967), Taylor (1971), UÅ”an (1977), GaliÄ (1989), etc.) to which by some rules one can assign corresponding algebraic structures
(partial quasigroups and partial groupoids). GaliÄ (1990) defines
U-k - seminets of the maximal degree and shows the existence and
construction in dependence on the set P over which one constructs
a k-seminet. In this paper it is shown how many U-k - seminets
of maximal degree Ī¼ can be constructed over the set P
for the given t-order
Lieb-Liniger gas in a constant force potential
We use Gaudin's Fermi-Bose mapping operator to calculate exact solutions for
the Lieb-Liniger model in a linear (constant force) potential (the constructed
exact stationary solutions are referred to as the Lieb-Liniger-Airy wave
functions). The ground state properties of the gas in the wedge-like trapping
potential are calculated in the strongly interacting regime by using
Girardeau's Fermi-Bose mapping and the pseudopotential approach in the
-approximation ( denotes the strength of the interaction). We point out
that quantum dynamics of Lieb-Liniger wave packets in the linear potential can
be calculated by employing an -dimensional Fourier transform as in the case
of free expansion
On NP - polyagroups
In the present paper: 1) an NP--polyagroup is defined as a
generalization of an group for and 2)
NP--polyagroups of the type is described as algebras
of the type [ ]
(m,n)-rings as algebras with only one operation
In this paper a class of (m,n)-rings with a left and right zero is described as a variety of algebras of type
SUBSTITUTIONAL MODEL OF THE SOIL BASED ON ARTIFICAL NEURAL NETWORKS
U radu je prikazana interpretacija rezultata mjerenja specifiÄnog otpora tla primjenom umjetnih neuronskih mreža. Model zasnovan na umjetnim neuronskim mrežama nadomjeÅ”ta tlo koje se fizikalno može smatrati kao dvoslojni medij s vertikalnom promjenom specifiÄnog elektriÄnog otpora i s vodoravnom granicom meÄu slojevima. UÄenje umjetne neuronske mreže provedeno je pod nadzorom sa skupom ulaznih podataka koji su dobiveni na temelju vrlo toÄnog teorijskog modela dvoslojnog tla. Predloženi algoritam; koji aproksimira nelinearne karakteristike tla koristeÄi umjetne neuronske mreže; pouzdano procjenjuje parametre tla i specifiÄnu elektriÄnu otpornost tla. Primjena nadomjesnog modela tla zasnovanog na neuronskim mrežama prikazana je na praktiÄnom primjeru odreÄivanja parametara dvoslojnog tla iz mjernih podataka dobivenih Wennerovom tehnikom mjerenja specifiÄnog otpora tla. Radi jednostavnosti izlaganja i usporedivosti modela strujne sonde (Å”tapovi) su nadomjeÅ”tene kuglastim elektrodama; odnosno toÄkastim izvorima polja. Dobiveni rezultati su prikazani analitiÄki i grafiÄki te diskutirani.This paper presents an interpretation of the results of measurement of specific soil resistivity by means of artificial neural networks.The model based on artificial neural networks replaces the soil which can be physically considered a two-layer medium with a vertical change of the specific electric resistivity and a horizontal boundary line between the layers. Learning of the neural network was performed under supervision using the input dataset obtained by means of a very accurate theoretical model of the double-layer soil. The proposed algorithm that approximates non-linear soil properties using the artificial neural network is reliable in assessment of the soil parameters and specific electric soil resistivity. Application of the substitutional model of the soil based on neural networks is demonstrated by a realistic example; determination of parameters of the double-layer soil from the measured data obtained by the Wenner technique for measuring the specific soil resistivity. For simplicity of presentation and model comparability; the current probes (poles) are replaced by the ball electrodes; i.e. spot field sources. The results obtained are analytically and graphically presented and discussed
Nonleptonic decays and the Skyrme model
Nonleptonic decay branching ratios are estimated by means of the
QCD enhanced effective weak Hamiltonian supplemented by the SU(3) Skyrme model
used to estimate the nonperturbative matrix elements. The model has only one
free parameter, namely the Skyrme charge , which is fixed through the
experimental values of the octet-decuplet mass splitting and the
axial coupling constant . The whole scheme is equivalent to that which
works well for the nonleptonic hyperon decays. The ratios of calculated
amplitudes are in agreement with experiment. However, the absolute values are
about twice too large if short-distance corrections and only ground
intermediate states are included.Comment: 4 pages, 1 figure, 1 table, version to appear in Phys.Rev.
Community-acquired pneumonia
Introduction: Community-acquired pneumonia (CAP) today, as well as a few decades ago, is a current medical problem considering the incidence and the mortality rate of the population, despite the availability of new and powerful antimicrobials and vaccines effectiveness. Objective: Analysis of outpatients diagnosed with pneumoniae, determination of the most common risk factors for their development, analysis of the success of outpatients' treatments and complications. Methods: Medical exams of 38 patients were analyzed. Each case is chosen by following previously prepared protocol, including patients with respiratory symptoms and infectious syndrome, positive auscultatory findings on the lungs which are radiologicaly confirmed and laboratory treated (SE, Le, FBC, the first and the tenth day of the therapy). Demographic data and associated illnesses, as well as a severity assessment of the illness, were made at the first medical examination, when pneumonia was suspected. Results: In the period from 01.11.2014 to 01.05.2015, there were 33 diagnosed pneumoniae. Associated illnesses, in population older than 65 years, were present in 92.85% of patients and some of them had two or three comorbidities. CRB65 proved itself as a good parameter in assessment of the disease severity for both groups. Applied antibiotic therapy proved to be effective in 80% of patients. There is no significant difference in pneumonia presentation with regards to gender and age. In data proccessing, descriptive statistics methods and no parameter x2 test were used for statistical significance assessment. Conclusion: All patients with clear indications should be hospitalized, but large percentage of patients can be treated in outpatints' facilities, with good patient cooperation. Also vaccination, as an available resource, seems to have not received a significant place in our environment
HistoloÅ”ka analiza zapaljenskih reakcija u periradikularnom tkivu i formiranja kalcifikovanog tkiva posle implantacije eksperimentalnih nanostrukturnih cemenata na bazi kalcijum silikata i hidroksiapatita u kanale korena zuba kuniÄa
The aim of the study was to evaluate inflammatory tissue reactions and the formation of calcified tissue after implantation of experimental nanostructured calcium silicate cement (CS) and hydroxyapatite with calcium silicate cement (HA-CS) into root canals of rabbits' teeth. The study was conducted on four rabbits of the genus Oryctolagus cuniculus. After instrumentation and irrigation, the root canals of the central incisors were dried and filled with CS, HA-CS and control material (MTA Angelus). The animals were sacrificed after 28 days. After histological preparation and hematoxylin-eosin staining, tissue samples were evaluated for the intensity and extension of inflammatory tissue reaction; continuity, morphology and thickness of the newly formed calcified tissue; and presence of giant cells, materials particles and microorganisms. Kruskal Wallis and Dunn's post hoc test were used for data analysis (Ī±=0.05). There were no significant differences in the intensity of inflammatory reactions between CS, HA-CS and MTA control. HA-CS showed significantly better results than MTA and CS with respect to continuity of the newly formed calcified tissue (P=0.003 and P=0.010, respectively). Significant differences in thickness of the calcified tissue existed between CS and MTA (P=0.004) and between HA-CS and MTA (P=0.012). Application of CS and HA-CS resulted in minimal inflammatory tissue response, similar to the MTA control. CS and HA-CS were more efficient than MTA in supporting hard tissue formation. The best organized newly formed calcified tissue was seen after HA-CS application.Cilj rada je bio da se ispitaju Kanali korena centralnih sekutiÄa su posle instrumentacije, ispiranja i suÅ”enja napunjeni materijalima CS, HA-CS i kontrolnim materijalom, mineral trioksid agregatom (MTA). Životinje su žrtvovane posle 28 dana. Posle histoloÅ”ke pripreme, uzorci tkiva su analizirani u pogledu inteziteta i raÅ”irenosti zapaljenske reakcije; kontinuiteta, morfologije i debljine novoformiranog kalcifi kovanog tkiva; prisustva džinovskih Äelija, Äestica materijala i mikroorganizama. Dobijeni rezultati su statistiÄki obraÄeni (Ī± = 0,05) Nisu uoÄene statistiÄki znaÄajne razlike u intezitetu zapaljenske reakcije izmeÄu CS, HA-CS i MTA. U pogledu kontinuiteta novostvorenog kalcifi kovanog tkiva HA-CS je pokazao bolje rezultate u odnosu na MTA i CS (p=0,003 i p=0,010). ZnaÄajne razlike utvrÄene su u pogledu debljine kalcifi kovanog tkiva izmeÄu CS i MTA (p=0,004), kao i HA-CS i MTA (p=0,012). Aplikacija materijala CS i HA-CS je rezultirala minimalnom zapaljenskom reakcijom tkiva, sliÄno kontrolnom materijalu (MTA). CS i HA-CS su bili efi kasniji u pogledu stimulacije formiranja kalcifi kovanog tkiva u odnosu na MTA. Najbolje organizovano novoformirano tkivo uoÄeno je posle aplikacije materijala HA-CS. zapaljenske reakcije u periradikularnom tkivu i formiranje kalcifi kovanog tkiva posle implantacije eksperimentalnih, nanostrukturnih cemenata na bazi kalcijum silikata (CS) i meÅ”avine hidroksiapatita i kalcijum silikata (HA-CS) u kanale korena zuba kuniÄa
Assessment of computed tomography simulators used in radiotherapy treatment planning in Serbia, Croatia, and Bosnia and Herzegovina
The purpose of this work was to evaluate computed tomography simulators used in radio-therapy treatment planning in Serbia, Croatia, and Bosnia and Herzegovina. A survey of quality assurance programmes of 24 computed tomography simulators in 16 facilities was conducted. A dedicated CT-to-ED phantom was scanned at 120 kV and 140 kV, to obtain CT-to-ED conversion curves as well as CTDIvol. Thoracal phantoms were scanned in the standard and extended field of view to evaluate the dosimetric effect on treatment planning and delivery. The mean age of the measured scanners was 5.5 years. The mean water HU value was ā6.5 (all scanners, all voltages) and air HU value was ā997. Extended field of view computed tomography data differ from the standard field of view and differences between conversion curves have significant dosimetric impact. The CTDI data showed a large range of values between centers. Better quality assurance of computed tomography simulators in all countries is recommended. The CT-to-ED curve could be used as default at one voltage and per manufacturer. Extended field of view imaging can be used, but treatment planning should be avoided in the regions out of the standard field of view
Utjecaj hijaluronske kiseline, kalcijeva hidroksida i dentinskih adheziva na odontoblaste i fibroblaste Ŕtakora
The aim of this study was to investigate the effects and efficiency of pulp capping preparations based on hyaluronic acid, calcium hydroxide, and dentin adhesive on the pulp tissue of Sprague-Dawley rats. The rats were killed and extracted teeth sectioned transversely through the pulp. The slices were placed in a RPMI 1640 cell culture medium supplemented with 10 % foetal calf serum. During 14 days of cultivation cultures were treated with preparations that contained hyaluronic acid (Gengigel ProfĀ®), and calcium hydroxide (ApexCalĀ®), or with dentin adhesive (ExciteĀ®). Cellularity and viability of fibroblasts and odontoblasts was analysed using a haemocytometer. Hyaluronic acid proved most efficient and the least toxic for direct pulp capping. Even though calcium hydroxide and dentin adhesive demonstrated a higher degree of cytotoxicity, their effects were still acceptable in terms of biocompatibility.Cilj ovog rada bio je istražiti djelovanje preparata na bazi hijaluronske kiseline i kalcijeva hidroksida te dentinskog adheziva na pulpno tkivo Sprague-Dawley Å”takora u svrhu procjene uÄinkovitosti navedenih materijala kod direktnog prekrivanja pulpe. IzvaÄeni zubi transverzalno su podijeljeni kroz pulpu. Naresci su uzgajani u RPMI 1640 staniÄnom mediju obogaÄenom s 10 % fetalnoga teleÄeg seruma u plastiÄnim boÄicama za staniÄnu kulturu. Kulture su tijekom 14 dana tretirane preparatima s hijaluronskom kiselinom (Gengigel ProfĀ®), kalcijevim hidroksidom (ApexCalĀ®) i dentinskim adhezivom (ExciteĀ®). Nakon 14 dana pristupilo se analizi staniÄnosti i vijabilnosti s pomoÄu hemocitometra. Iako su preparati na bazi kalcijeva
hidroksida i dentinski adheziv pokazali neÅ”to viÅ”i stupanj citotoksiÄnosti, dobiveni su rezultati u granicama biokompatibilnosti. Primjena preparata na bazi hijaluronske kiseline postigla je najbolje rezultate te se ovaj materijal pokazao najboljim za direktno prekrivanje pulpe izmeÄu tri ispitivana preparata
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