'Multi-directed graph complexes and quasi-isomorphisms between them I: oriented graphs

We construct a direct quasi-isomorphism from Kontsevich's graph complex GC_n to the oriented graph complex OGC_{n+1}, thus providing an alternative proof that the two complexes are quasi-isomorphic. Moreover, the result is extended to the sequence of multi-oriented graph complexes, where GC_n and OGC_{n+1} are the first two members. These complexes play a key role in the deformation theory of multi-oriented props recently invented by Sergei Merkulov

Sueños dentro-fuera: algunos usos del sueño en la teoría social y la investigación etnográfica

In the last decade citizens of Serbia have described their bewildering social world in the idioms of magical realism, conspiracy theories, amorphous substances, kafkian burocratic parables, twilight, in-between states of consciousness. The social world was also likened to a dream or nightmare. Taking this cue from informants, I ask whether the Serbian “imaginary” might not be more fruitfully figured as a “dream” than as a “text,” or a “depository of dialogically intertwined narratives” -“stories Serbs tell themselves and others about themselves”-, as is frequent in “interpretative anthropology.” In order to extract its maximal figurative potential, I thread the dream trope through Marxist social theory as a site of its most fruitful use -from its anticipation in Marx’s varied figurations of modern capitalism’s peculiar enchantments to its full development in the work of Siegfried Kracauer and Walter Benjamin-. I then turn from these ethnographers of metropolitan modernity to anthropological theory and the way it historically conceptualized the dream in the exotic peripheries it studied. By threading it through metropolitan social theory as well as the ethnography of peripheries, I seek to show the internal complexity of dream as a figure and to recommend its use to anthropology in the figuring of social thought and action.En la última década, los ciudadanos de Serbia han venido describiendo su desconcertante mundo social a través del lenguaje del realismo mágico, las teorías de la conspiración, sustancias amorfas, parábolas kakfianas sobre la burocracia, crepúsculos, estados de conciencia alterados. El mundo social se ha asociado también a un sueño o a una pesadilla. Retomando el hilo de los informantes, en este ensayo cuestiono si el “imaginario” serbio no podría representarse de una forma más fructífera como un “sueño” antes que como un “texto” o un “depósito de narrativas dialógicamente entrecruzadas” -“las historias serbias, por sí mismas, hablan tanto de los serbios como de los otros”-, como se dice frecuentemente en la “antropología interpretativa”. Con el objeto de extraer su máximo potencial figurativo, considero el tropo del sueño desde la teoría social marxista, a partir de sus elaboraciones más productivas -desde la anticipación de las variadas representaciones de Marx sobre los fetichismos específicos del capitalismo moderno a sus desarrollos completos en la obra de Siegfried Kracauer y Walter Benjamin-. Luego regreso desde estos etnógrafos de la modernidad metropolitana a la teoría antropológica y a la forma en que históricamente ésta ha conceptualizado el sueño en las periferias exóticas que ha estudiado. Al “trabar” la teoría social de las sociedades industrializadas con la etnografía de las periferias, trato de mostrar la complejidad interna del sueño como figura, así como alentar su uso dentro de la antropología en la representación de la acción y del pensamiento social

Differentials on graph complexes III: hairy graphs and deleting a vertex

We continue studying the cohomology of the hairy graph complexes which compute the rational homotopy of embedding spaces, generalizing the Vassiliev invariants of knot theory, after the second part in this series. In that part we have proven that the hairy graph complex HGC_{m,n} with the extra differential is almost acyclic for even m. In this paper, we give the expected same result for odd m. As in the previous part, our results yield a way to construct many hairy graph cohomology classes by the waterfall mechanism also for odd m. However, the techniques are quite different. The main tool used in this paper is a new differential, deleting a vertex in non-hairy Kontsevich’s graphs, and a similar map for hairy vertices. We hope that the new differential can have further applications in the study of Kontsevich’s graph cohomology. Namely it is conjectured that the Kontsevich’s graph complex with deleting a vertex as an extra differential is acyclic

A questionnaire for assessing fear of radiotherapy in oncology patients

© 2018, University of Kragujevac, Faculty of Science. All rights reserved. Radiotherapy is a frequently prescribed and highly effective form of treatment of oncology patients. However, many patients feel rational or irrational fear of the application of radiotherapy, which may provoke mental and physical stress, anxiety, growing anger and hostility, thus reducing quality of life. The aim of this study was to develop, reliability test and validate a questionnaire for assessing the level of fear of radiotherapy in oncology patients. We performed a prospective qualitative study based on the development, validation and reliability testing of the questionnaire developed for assessing radiotherapy-caused fear in oncology patients treated in the Centre for Oncology and Radiology, Department of Radiotherapy, Clinical Centre Kragujevac. The study included 154 patients and the final version of the questionnaire integrated 15 questions. After the elimination of inappropriate questions the Cronbach coefficient α was 0.946. The questionnaire consists of two factors which represent 57.423% and 6.925%, making a total of 64.348% of the variance of the questionnaire. The results of our study show that the questionnaire used is a unique, reliable and valid instrument for assessing the level of fear of radiotherapy in oncology patients the application of which will allow us to identify patients with elevated levels of fear of radiotherapy

Sagnac effect in a chain of mesoscopic quantum rings

The ability to interferometrically detect inertial rotations via the Sagnac effect has been a strong stimulus for the development of atom interferometry because of the potential 10^{10} enhancement of the rotational phase shift in comparison to optical Sagnac gyroscopes. Here we analyze ballistic transport of matter waves in a one dimensional chain of N coherently coupled quantum rings in the presence of a rotation of angular frequency, \Omega. We show that the transmission probability, T, exhibits zero transmission stop gaps as a function of the rotation rate interspersed with regions of rapidly oscillating finite transmission. With increasing N, the transition from zero transmission to the oscillatory regime becomes an increasingly sharp function of \Omega with a slope \partialT/\partial \Omega N^2. The steepness of this slope dramatically enhances the response to rotations in comparison to conventional single ring interferometers such as the Mach-Zehnder and leads to a phase sensitivity well below the standard quantum limit

HALLUCINATORY EXPERIENCES IN VISUALLY IMPAIRED INDIVIDUALS: CHARLES BONNET SYNDROME – IMPLICATIONS FOR RESEARCH AND CLINICAL PRACTICE

Background: Charles Bonnet syndrome (CBS) refers to visual hallucinations that occur in individuals with preserved cognitive functions associated with visual impairment. Methods: This article reviews occurence of visual hallucinations in subjects with CBS by journals published in English in the Pubmed database in the period 1992-2018. Criteria for selection of appropriate papers were sufficient information and perspicuous view on pathogenesis, epidemiology, clinical presentation and treatment possibilities of CBS. Results: Most commonly, visual hallucinations in patients with CBS are complex, repetitive and stereotyped. Such individuals have preserved insight that those percepts are not real, and there is an absence of secondary explanatory delusions and hallucinations within other modalities. Seeing as the aforementioned percepts do not share all the characteristics of hallucinations, it remains unresolved how they should be referred to. Terms as release hallucinations, one that is reflecting its underlying pathogenesis, or confabulatory hallucinatory experiences have been proposed. Moreover, CBS has also been referred to as phantom vision syndrome and may occur in any ophthalmological disease. It is not particularly connected with loss of function along any level of the visual pathway. Although this syndrome is mostly associated with age-related macular degeneration, glaucoma and cataract, it could be related to almost any other ophthalmological conditions. The incidence of CBS alongside with mostly other ocular pathology is rising as population is ageing. Conclusions: Nonetheless, CBS remains commonly underreported, under recognized and/or misrecognized. Albeit the treatment recommendations and guidelines are not yet fully established, it is important to raise awareness of this specific and distinct condition, which inevitably implicates many differential diagnostic deliberations