On two-distillable Werner states

We consider bipartite mixed states in a $d\otimes d$ quantum system. We say that $\rho$ is PPT if its partial transpose $1 \otimes T (\rho)$ is positive semidefinite, and otherwise $\rho$ is NPT. The well-known Werner states are divided into three types: (a) the separable states (the same as the PPT states); (b) the one-distillable states (necessarily NPT); and (c) the NPT states which are not one-distillable. We give several different formulations and provide further evidence for validity of the conjecture that the Werner states of type (c) are not two-distillable.Comment: 19 pages, expanded version containing new result

Canonical matrices of bilinear and sesquilinear forms

Canonical matrices are given for (a) bilinear forms over an algebraically closed or real closed field; (b) sesquilinear forms over an algebraically closed field and over real quaternions with any nonidentity involution; and (c) sesquilinear forms over a field F of characteristic different from 2 with involution (possibly, the identity) up to classification of Hermitian forms over finite extensions of F. A method for reducing the problem of classifying systems of forms and linear mappings to the problem of classifying systems of linear mappings is used to construct the canonical matrices. This method has its origins in representation theory and was devised in [V.V. Sergeichuk, Math. USSR-Izv. 31 (1988) 481-501].Comment: 44 pages; misprints corrected; accepted for publication in Linear Algebra and its Applications (2007

Uticaj slušnog uzrasta na razumevanje verbalnih naloga kohlearno implantirane dece

Hearing age is defined as a period of using any amplification. Most researches indicate that hearing age influences the developmental rate of auditory and speech-language abilities in deaf children, especially when cochlear implantation was performed before the age of three. This research is aimed at analyzing the influence of hearing age on understanding verbal instructions in children with cochlear implants. The sample consists of 23 children with cochlear implants and 21 children with normal hearing, aged between 4 and 10. Hearing age of children with cochlear implants was between 2 and 7 years. Token Test with toys, adapted for children with hearing impairments, was used to analyze understanding verbal instructions. The results indicate that there are statistically significant differences between children with cochlear implants and children with normal hearing, aged between 4 and 7, on all subtests and the total score regardless of the hearing age (sub1 p lt 0.001, sub2 p lt 0.000, sub3 p lt 0.001, total score p lt 0.000). No statistically significant differences were determined on any of the subtests in children aged between 7.1 and 10, regardless of the hearing age. Comparative results analysis within the experimental group of children with different hearing age indicates that the difference in understanding verbal instructions between these two groups is not statistically significant.Slušni uzrast se definiše kao vremenski period korišćenja amplifikacije. Većina istraživanja pokazuju da slušni uzrast utiče na brzinu formiranje slušnih i govorno-jezičkih sposobnosti gluve dece, naročito ako je kohlearna implantacija urađena pre treće godine života. Istraživanje je bilo usmereno na ispitivanje uticaja slušnog uzrasta na razumevanje verbalnih naloga kohlearno implantirane dece. Uzorkom je bilo obuhvaćeno 23 kohlearno implantirane dece i 21 dete urednog sluha uzrasta od 4 do 10 godina. Slušni uzrast kohlearno implantirane dece se kretao od 2 do 7 godina. Za ispitivanje razumevanja verbalnih naloga korišćen je Token test sa igračkama koji je adaptiran za decu oštećenog sluha. Analiza rezultata je pokazala da postoje statistički značajne razlike između kohlearno implantirane i čujuće dece na svim subtestovima i u ukupnom skoru na uzrastu od 4 do 7 godina bez obzira na slušni uzrast (subtest1 p lt 0,001, subtest2 p lt 0,000, subtest3 p lt 0,001, ukupan skor p lt 0,000), a na uzrastu od 7,1 do 10 godina statistički značajna razlika nije uočena ni na jednom subtestu takođe bez obzira na slušni uzrast. Komparativna analiza rezultata unutar eksperimentalne grupe između dece različitog slušnog uzrasta pokazala je da razlika između ove dve grupe u razumevanju verbalnih naloga nije statistički značajna

D-optimal matrices of orders 118, 138, 150, 154 and 174

We construct supplementary difference sets (SDS) with parameters $(59;28,22;21)$, $(69;31,27;24)$, $(75;36,29;28)$, $(77;34,31;27)$ and $(87;38,36;31)$. These SDSs give D-optimal designs (DO-designs) of two-circulant type of orders 118,138,150,154 and 174. Until now, no DO-designs of orders 138,154 and 174 were known. While a DO-design (not of two-circulant type) of order 150 was constructed previously by Holzmann and Kharaghani, no such design of two-circulant type was known. The smallest undecided order for DO-designs is now 198. We use a novel property of the compression map to speed up some computations.Comment: 14 pages. arXiv admin note: substantial text overlap with arXiv:1409.596

An approach to analysis of dynamic crack growth at bimaterial interface

In this paper is presented the new approach to asymptotic analysis of the stress and strain fields around a crack tip that is propagating dynamically along a bimaterial interface. Through asymptotic analysis the problem is being reduced to solving the Riemann-Hilbert's problem, what yields the strain potential that is used for determination of the strain field around a crack tip. The considered field is that of a dynamically propagating crack with a speed that is between zero and shear wave speed of the less stiffer of the two materials, bound along the interface. Using the new approach in asymptotic analysis of the strain field around a tip of a dynamically propagating crack and possibilities offered by the Mathematica programming package, the results are obtained that are compared to both experimental and numerical results on the dynamic interfacial fracture known from the literature. This comparison showed that it is necessary to apply the complete expression obtained by asymptotic analysis of optical data and not only its first term as it was done in previous analyses

Ethiopathogenesis, diagnostics and therapy of foal neonatal septicemia

Sepsis is very frequent cause of neonatal foal deaths. It is systemic inflammation developing after infective agents break into in the foal circulation with progressive disturbance of health not responding to intensive therapy. Systemic inflammatory response and development of the shock in first phase of the sepsis development lead to massive organ damages and progression of organ dysfunction syndrome further promoting loss of homeostatic mechanisms and death of foal. During the period of three decades high mortality rate of newborn foals have been reported. Among most frequent causes of foal deaths beside EHV1 infection, bacterial sepsis mostly accompanied with insufficient colostral immunity transfer was documented. Fast development of the non-specific symptoms and shock in foals are often misleading diagnostics thus prolonging the onset of specific therapy. Therefore the effective clinical procedures, beside close observation of newborn foals, depend upon fast recognition of mechanisms of infection and shock development. Since time-consuming procedure is necessary for identification of the causative infective agent and the evaluation of its susceptibility on antibiotics, the therapy if symptomatic and include intravenous administration of fluids in aim to correct glycaemia and acid-base disturbance, antibiotic and antiendotoxic treatment, and substitutive treatment of immunoglobulin deficiency in all cases of passive immune transfer failure involved in sepsis development.

The state of security of today’s world after 70 years of the United Nations

At a time when the United Nations mark 70 years of its existence, when the leaders of the 193 member states of this world organization adopted, with a lot of faith, a transformative 2030 Agenda for Sustainable Development, the world is faced with many difficult challenges to security. Effective indicators of contemporary international security, as well as the challenges, risks and threats that reflect it, show that the security of the modern world has been jeopardized, directly or indirectly, in the highest possible degree, since the end of the Second World War. That is why there is increasing importance of the United Nations, which, with all its drawbacks over the past seventy years, have represented the best model of multilateral cooperation in the field of security and without whose existence the world would have much larger international problems. The efforts this organization makes with the aim to protect and establish peace in the world must be respected, and the contents of the UN General Assembly resolution 59/565 A of 2004, devoted to threats to the international security, should be seen in that light as well

Razvoj auditivne pažnje

This paper presents an overview of developmental findings on auditory attention and its main components. Unlike visual attention that has been excessively studied in infants and children, auditory attention studies in the youngest population are sparse. However, during the last decade, there has been an increase in the number of studies, especially electrophysiological ones carried out on infants. Our review starts with Posner's seminal theoretical and experimental work gradually developing into a neuropsychological model of attention. Basic components of auditory attention are presented with the focus on selective auditory attention and the MMN as its electrophysiological correlate. In conclusion, we return to the psychological concepts of interpreting developmental changes in auditory attention. The psychological level of analysis shows interconnectivity of all attentional components as well as the relation between attention and other aspects of cognitive and emotional development.Rad predstavlja pregled razvojnih istraživanja u okviru auditivne pažnje i njenih glavnih komponenti. Za razliku od vizuelne pažnje odojčadi i dece, istraživanja auditivne pažnje kod najmlađe populacije su daleko manje prisutna. Međutim, poslednja dekada beleži porast istraživanja posebno onih koja primenjuju elektrofiziološke parametre. Pregled počinje prikazom Posnerovog rada koji je rezultirao uticajnim neuropsihološkim modelom pažnje. U okviru prikaza auditivne pažnje, predstavljamo osnovne komponente ove funkcije, sa akcentom na selektivnu auditivnu pažnju i MMN kao njen glavni elektrofiziološki korelat. U zaključku se oslanjamo na psihološki nivo interpretacije razvojnih promena u auditivnoj pažnji. Ovaj nivo pokazuje međusobnu povezanost svih komponenti pažnje, kao i vezu auditivne pažnje sa kognitivim i emocionalnim dimenzijama ličnosti

A regularization algorithm for matrices of bilinear and sesquilinear forms

We give an algorithm that uses only unitary transformations and for each square complex matrix constructs a *congruent matrix that is a direct sum of a nonsingular matrix and singular Jordan blocks.Comment: 18 page