Robust Bayes-Like Estimation: Rho-Bayes estimation

We consider the problem of estimating the joint distribution $P$ of $n$ independent random variables within the Bayes paradigm from a non-asymptotic point of view. Assuming that $P$ admits some density $s$ with respect to a given reference measure, we consider a density model $\overline S$ for $s$ that we endow with a prior distribution $\pi$ (with support $\overline S$) and we build a robust alternative to the classical Bayes posterior distribution which possesses similar concentration properties around $s$ whenever it belongs to the model $\overline S$. Furthermore, in density estimation, the Hellinger distance between the classical and the robust posterior distributions tends to 0, as the number of observations tends to infinity, under suitable assumptions on the model and the prior, provided that the model $\overline S$ contains the true density $s$. However, unlike what happens with the classical Bayes posterior distribution, we show that the concentration properties of this new posterior distribution are still preserved in the case of a misspecification of the model, that is when $s$ does not belong to $\overline S$ but is close enough to it with respect to the Hellinger distance.Comment: 68 page

Photoluminescence study of terbium-exchanged ultrastable Y zeolites: number of species, photoluminescence decays, and decay-associated spectra

Terbium-exchanged ultrastable Y (USY) zeolites were investigated by using time-resolved photoluminescence spectroscopy techniques and methods. To determine the distribution of terbium species in USY zeolites together with their photoluminescence properties, several analysis methods for the time-resolved luminescence spectra were used such as the area normalization of time-resolved photoluminescence spectra, singular value decomposition, global nonlinear least squares, and the maximum entropy. Except for a questionable long lifetime, small contribution of a terbium species with lifetime of 1.9¿2.1 ms, all the experimental and analysis results converged to a two terbium species distribution with lifetimes varying between 410¿440 and 1000¿1100 μ s . The effects of the silylation of terbium-exchanged USY zeolites with phenyl-, vinyl-, and hexadecyltrimethoxysilanes on the lanthanide¿s photoluminescence properties were also described

The kinetics and mechanism of the organo-iridium catalysed racemisation of amines

The dimeric iodo-iridium complex [IrCp*I2 ]2 (Cp*=pentamethylcyclopentadiene) is an efficient catalyst for the racemisation of secondary and tertiary amines at ambient and higher temperatures with a low catalyst loading. The racemisation occurs with pseudo-first-order kinetics and the orresponding four rate constants were obtained by monitoring the time dependence of the concentrations of the (R) and (S) enantiomers starting with either pure (R) or (S) and show a first-order dependence on catalyst concentration. Low temperature 1H NMR data is consistent with the formation of a 1:1 complex with the amine coordinated to the iridium and with both iodide anions still bound to the metal-ion, but at the higher temperatures used for kinetic studies binding is weak and so no saturation zero-order kinetics are observed. A cross-over experiment with isotopically labelled amines demonstrates the intermediate formation of an imine which can dissociate from the iridium complex. Replacing the iodides in the catalyst by other ligands or having an amide substituent in Cp* results in a much less effective catalysts for the racemisation of amines. The rate constants for a deuterated amine yield a significant primary kinetic isotope effect kH/kD = 3.24 ndicating that hydride transfer is involved in the rate-limiting step

Catalytic Behavior of Metal Active Sites From Modified Mesoporous Silicas in Oxidation of Organic Compounds

The ordered mesoporous silicas containing transition metals are versatile catalytic materials for oxidation of a wide range of organic compounds. In order to obtain active catalysts, different active redox metal sites have been introduced into specific locations (mesoporous channels and framework) of ordered mesoporous silicas (OMSs). All the reported results evidenced that localization of metal ions, their interaction with another metal (bimetallic catalysts) and the support, with typical properties of the ordered mesoporous silica, influenced the oxidation state, respectively their redox properties. To support this, the results regarding the specific properties of transitional metals in the ordered structure of silica, obtained using various characterization methods, were presented. The activity of metal sites in the oxidation reactions was evidenced in various applications carried out in the liquid or gaseous phase. The oxidation of various organic compounds in liquid phase with H2O2 (especially aromatic compounds and of alcohols) and in gas phase with oxygen from air was presented for a variety of metal-modified OMSs. The active sites and possible reaction mechanisms were presented for some catalytic systems. The immobilization of multiple metal active species on new ordered porous frameworks and their synergistic interactions remain topics of interest in the future

The Critical Innovation Discourse of Small VODs: The Case of The Death of Mr. Lăzărescu on Cinepub

My article compares the catalogues and interfaces of a small and a big VOD provider and emphasizes the critical innovative potential of the intervention of the former and, more generally, of small streaming services. I employ a cultural studies approach and closely read the acts of curation of these two types of providers. As a case study, I focus on the curation of the feature film The Death of Mr. Lăzărescu on both platforms. By critical innovation, I understand an economic or industrial intervention that questions and disrupts hegemonic discourses in its field. In the case of VODs, it refers to an engagement with discourses on digital film consumption, the branding of premium content, establishment of taste, and diversity of content. I also approach critical innovation as political and economic. I provide proof that small non-profit providers set up more advantageous viewing experiences that benefit a film and its makers. I also show that they play an important role in maintaining the sustainability of a digital distribution ecosystem

Old Europe, New Europe, Eastern Europe: Reflections on a Minor Character in Fassbinder’s Ali, Fear Eats the Soul

In today\u27s Europe, the term Eurosceptic often accompanies accusations of retrograde nationalism, irrational feelings, even fanaticism. When applied to Europe, skepticism, one of the critic\u27s formative traits, acquires a bad reputation, as if it can only be an annihilating, rather than constructive, form of doubt. And yet skepticism is a much-needed critical affect, particularly when it comes to Europe. If we need to be skeptical of anything, it is Europe. Today one hears claims about Europe having become postnational, postracial, even post-Europe. How else can the literary and cultural critic welcome such claims other than with a healthy dose of skepticism

Narracje okrucieństwa: dzieła filmowe Cristiana Mungiu, a polityczne imaginarium Europy Środkowo-Wschodniej

This article employs Lauren Berlant’s concepts of cruel optimism and impasse to explain the way the cinematic work of Cristian Mungiu comments on the condition of small East-Central European cultures. The article analyzes 4 Months, 3 Weeks and 2 Days (2007), Beyond the Hills (2012) and Graduation (2016), and draws evidence from the narrative structure of these films, gender and social and economic condition of their characters, as well as the audiovisual poetics of their endings. The main point of the article is that Mungiu’s films criticize a mental mapping East-Central Europe with origins in the Cold War that imagines it as a region of small nations in the permanent state of danger and in need of urgent protection. Mungiu’s films show that this mapping exposes these cultures to inescapable cycles of political abuse. The slow and contemplative endings of Mungiu’s films also propose a solution. They gesture toward the development of a condition of political hovering that, as interruption, may enable East-Central European political imaginaries to envision more creative solutions to escape cycles of abuse. This interruption is linked to the memory of 1989 and to the historical openness 1989 created. As a political approach for East-Central European cultures, interruption is a strategy of letting one’s political imaginary be inspired to the opening of 1989.Celem poniższego artykułu jest przedstawienie sposobu opisu stanu pomniejszych kultur Europy Środkowo-Wschodniej w filmach Cristiana Mungiu. Rozważania te zostały oparte o pojęcia okrutnego optymizmu oraz impasu autorstwa Lauren Berlant. Analizie poddano filmy 4 Months, 3 Weeks and 2 Days (2007), Beyond the Hills (2012) oraz Graduation (2016). Pod uwagę wzięto w szczególności strukturę narracyjną wspomnianych dzieł, płeć bohaterów, uwarunkowania społeczno-ekonomiczne wpływające na ich byt, a także poetykę mediów audio-wizualnych prezentowaną w zakończeniach filmów. Autor argumentuje, że filmy Mungiu stanowią krytykę mapowania wyobrażeniowego na terenach Europy Środkowo-Wschodniej zapoczątkowanego w czasach zimnej wojny, która prezentuje narody zamieszkujące te tereny jako skazane na nieustanne przebywanie w stanie zagrożenia, a co za tym idzie, niewygasającą potrzebę obrony, co naraża je na przeżywanie nieuniknionych cykli politycznych nadużyć. Propozycja rozwiązania przedstawiona jest w powolnych, skłaniających do przemyśleń zakończeniach filmów. Wskazują one na rozwój sytuacji politycznego zawieszenia, która jako zakłócenie statusu quo może pozwolić wyobraźniom politycznym na stworzenie rozwiązań bardziej kreatywnych, pozwalających uniknąć wspomnianych cykli. Przerwa ta wiąże się z pamięcią wydarzeń roku 1989, a także historyczną otwartością, która emergowała w owym czasie. Jako polityczny paradygmat kultur środkowo-wschodnioeuropejskich, zawieszenie jest strategią, która pozwala na zmianę postawy wyobrażeniowej wobec początku roku 1989