The formation of carbonaceous layer from ethylene over various transition metal catalysts – an FT-IR study

The ethylene-derived carbonaceous overlayers were studied over silica-supported Pt, Pd, Rh and Cu catalysts by FT-IR spectroscopy under desorption conditions. As a general feature it was observed over all catalysts that upon increasing the desorption temperature the overlayer gradually became poor in hydrogen. The structure of the overlayers was similar over the silica-supported Pt, Pd and Rh. On increasing the reaction temperature the σ-adsorbed half-hydrogenated species are transformed to adsorbed ethylidyne. On the Cu catalyst prepared with ion exchange a similar picture emerged, while on those prepared with precipitation ethylidyne soon became the predominant species. Hydrogen swept off the carbonaceous species from the transition metals, however, copper retained large portions of it

Egy új roncsolásmentes geokémiai módszer - a PGAA - archeometriai alkalmazásai = Applications of a New Non-destructive Geochemical Method (PGAA) in Archaeometry

Kőeszközök közül obszidián, radiolarit, flint, limnokvarcit pattintott-, valamint bazalt, dolerit, zöldpala-kontakt metabázit csiszolt eszközök és szerszámkövek nyersanyageredet-vizsgálatát végeztük elsősorban roncsolásmentes PGAA-val. Horvát és bosnyák ásatásokról származó obszidián régészeti leletekről megállapítottuk, hogy nyersanyaguk mediterrán (Lipari), ill. kárpáti (Tokaj-hg.) eredetű. A két nyersanyagellátási terület határát Bosznia középső részén valószínűsítjük. Elsőként szolgáltattunk analitikai alapadatokat radiolarit, és más kova kőeszközökről. Megmutattuk, hogy az ÉNy-horvátországi kovás nyersanyagok gyenge minőségűek, feltehetően csupán helyi eszközkészítésre használták. Vizsgáltuk a Magyar Nemzeti Múzeum Ebenhöch gyűjteményét és a gorzsai késő neolit lelőhely csiszolt kőeszköz leleteit. Alap adatbázist hoztunk létre a magyarországi csiszolt kőeszközök és néhány potenciális nyersanyag PGAA mérési eredményeiből. Pontosítottuk a felsőcsatári és a cseh-masszívumbeli zöldpala-metabázit kőzettípusok elkülöníthetőségét, jó eredményeket értünk el a bazalt-dolerit-alkáli dolerit elkülönítésében. A PGAA mérések alapján számos finomszemcsés kőeszköz kőzettípusát tisztáztuk. A Bükki kultúra kerámiáiról geokémiai adatokkal (XRF, kiegészítő PGAA) bizonyítottuk, hogy a jellegzetes finomkerámia típus nem a nyersanyag kémiai-ásványos összetétele, hanem fizikai-technológiai tulajdonságai miatt egyedi. Létrehoztunk egy régészeti kerámia adatbázist (CERAMIS). | We performed provenance research of chipped stone tools (obsidian, radiolarite, flint, etc.), as well as of polished stone tools (basalt, greenschist, etc) and other stone utensils – with non-destructive PGAA. We established a differentiation between the Mediterranean (Lipari) and Carpathian (Tokaj) origin obsidian archaeological objects, found in Croatia and Bosnia. A border of the two supply areas supposed to exist in central Bosnia. The first basic analytical data of radiolarite and other silex stone tools were provided. It was shown that the poor quality North-western Croatian silex was used probably for local production. Polished stone tools from Ebenhöch Collection of the Hungarian National Museum and the stone assemblage of the late Neolithic Gorzsa site were also studied. A PGAA database of Hungarian origin polished stone objects and their raw materials was set. A more accurate distinction between greenschist-metabasite from Felsőcsatár and the Bohemian Massif was done. Based on PGAA results, typology of some fine-grained stone tools was cleared up. We also investigated Neolithic ceramics from Northern Hungary (Bükk culture). We proved with geochemical experimental data (XRF and PGAA) that the typical finegrain ceramics are distinctive in their physical-technological properties, rather than in their raw material composition. Finally, a database of archaeological ceramics (CERAMIS) was created

Direct asymmetric reduction of levulinic acid to gamma-valerolactone: synthesis of a chiral platform molecule

Levulinic acid was directly converted to optically active (S)-gamma-valerolactone, a proposed biomass-based chiral platform molecule. By using a SEGPHOS ligand-modified ruthenium catalyst in methanol as a co-solvent, eventually, 100% chemoselectivity, and 82% enantioselectivity were achieved. The effect of the catalyst composition and reaction parameters on the activity and selectivity was investigated in detail. The conversion of a “real” biomass derived levulinic acid to optically active GVL without decreasing the enantioselectivity was also demonstrated

Attention and Social Cognition in Virtual Reality:The effect of engagement mode and character eye-gaze

Technical developments in virtual humans are manifest in modern character design. Specifically, eye gaze offers a significant aspect of such design. There is need to consider the contribution of participant control of engagement. In the current study, we manipulated participants’ engagement with an interactive virtual reality narrative called Coffee without Words. Participants sat over coffee opposite a character in a virtual café, where they waited for their bus to be repaired. We manipulated character eye-contact with the participant. For half the participants in each condition, the character made no eye-contact for the duration of the story. For the other half, the character responded to participant eye-gaze by making and holding eye contact in return. To explore how participant engagement interacted with this manipulation, half the participants in each condition were instructed to appraise their experience as an artefact (i.e., drawing attention to technical features), while the other half were introduced to the fictional character, the narrative, and the setting as though they were real. This study allowed us to explore the contributions of character features (interactivity through eye-gaze) and cognition (attention/engagement) to the participants’ perception of realism, feelings of presence, time duration, and the extent to which they engaged with the character and represented their mental states (Theory of Mind). Importantly it does so using a highly controlled yet ecologically valid virtual experience

Watching closely: Spatial distance influences theory of mind responding in film viewers

Shot scale in film, that is the apparent spatial distance of characters from the camera, is one of the most important compositional elements in a film shot guiding media audiences’ attention. The primary aim of the present study was to investigate the extent to which apparent spatial distance of fictional characters can evoke theory of mind responding in film viewers. Theory of mind, referring to the capacity of attributing mental states to others, is considered fundamental in audiences’ character involvement and narrative understanding, and it presumably mediates narrative effects. Four short animated movies were annotated for shot scale distribution and presented to participants (N = 52) in a within-subject design. Participants were asked to retell the story of the films and fill in questionnaires on narrative experience. Skin conductance was also measured during exposure. Story-descriptions were content analysed for theory of mind responses. In a Poisson-regression model average spatial distance predicted theory of mind response indicating that increasing spatial proximity triggered higher occurrence of mental state references in participants’ story-descriptions. The findings give insight into how the visual presentation of characters shapes audiences’ mental models of the story

Co-Detection of VEGF-A and Its Regulator, microRNA-181a, May Indicate Central Nervous System Involvement in Pediatric Leukemia

Central nervous system (CNS) involvement is a leading cause of therapy-refractory pediatric acute lymphoblastic leukemia (pALL), which is aggravated by underdiagnosing CNS disease with the currently used cell-based approach of cerebrospinal fluid (CSF) diagnostics. Our study focused on developing novel subcellular CNS leukemia indicators in the CSF and the bone marrow (BM) of patients with pALL. Serial liquid biopsy samples (n = 65) were analyzed by Elisas to measure the level of essential proteins associated with blast cell CNS trafficking, vascular endothelial growth factor A (VEGF-A) and integrin alpha 6 (ITGA6). In CSF samples from early induction chemotherapy, VEGF-A concentration were uniformly elevated in the CNS-positive group compared to those patients without unambiguous meningeal infiltration (9 vs Nine patients, Δc = 17.2 pg/ml, p = 0.016). Expression of miR-181a, a VEGFA-regulating microRNA which showed increased level in CNS leukemia in our previous experiments, was then paralleled with VEGF-A concentration. A slight correlation between the levels of miR-181a and VEGF-A indicators in CSF and BM samples was revealed (n = 46, Pearson’s r = 0.36, p = 0.015). After validating in international cohorts, the joint quantification of miR-181a and VEGF-A might provide a novel tool to precisely diagnose CNS involvement and adjust CNS-directed therapy in pALL

Approximating multi-dimensional Hamiltonian flows by billiards

Consider a family of smooth potentials $V_{\epsilon}$, which, in the limit $\epsilon\to0$, become a singular hard-wall potential of a multi-dimensional billiard. We define auxiliary billiard domains that asymptote, as $\epsilon\to0$ to the original billiard, and provide asymptotic expansion of the smooth Hamiltonian solution in terms of these billiard approximations. The asymptotic expansion includes error estimates in the $C^{r}$ norm and an iteration scheme for improving this approximation. Applying this theory to smooth potentials which limit to the multi-dimensional close to ellipsoidal billiards, we predict when the separatrix splitting persists for various types of potentials