The Unusual Spitzer Spectrum of the Carbon Star IRAS 04496–6958: A Different Condensation Sequence in the LMC?

We present a new Spitzer Infrared Spectrograph (IRS) spectrum of the carbon star IRAS 04496-6958 in the Large Magellanic Cloud, which exhibits a fairly broad absorption feature at ~11 μm. This feature is consistent with SiC absorption, as seen in a few Galactic sources. Furthermore, the C2H2 (and other molecular) absorption bands are the deepest ever observed, indicative of a very high column density. While the Galactic sources with SiC absorption have cool colors (continuum temperature ≈300 K), IRAS 04496-6958 is much bluer, with a continuum temperature of ≈600 K. Based on the Galactic sample, SiC dust at this temperature should still display an emission feature at ~11 μm. If SiC is the cause of the absorption feature, it suggests a subtly different evolutionary path and a change to a different condensation sequence than assumed for Galactic carbon stars. An alternative explanation for this feature is molecular line absorption; however, currently available line lists are not sufficient to properly assess this hypothesis

Concurrence in arbitrary dimensions

We argue that a complete characterisation of quantum correlations in bipartite systems of many dimensions may require a quantity which, even for pure states, does not reduce to a single number. Subsequently, we introduce multi-dimensional generalizations of concurrence and find evidence that they may provide useful tools for the analysis of quantum correlations in mixed bipartite states. We also introudce {\it biconcurrence} that leads to a necessary and sufficient condition for separability.Comment: RevTeX 7 page

Różewicz about himself as someone else

It seems that Tadeusz Różewicz’s poem titled Francis Bacon or Diego Velazquez in a Dentist’s Chair is dedicated to the works of the author of Studies of Crucifixion. In fact, Różewicz writes about the impression that Bacon’s art left on him when he saw it in galleries and museums. This poem is also about fascination. Contrary to what may seem intuitive, it is not an attempt to describe the poet’s own way of interpreting these works; and even if so, this is only true to a limited extent. For Różewicz, Bacon’s works were just a pretext to look at himself, especially at his own early poems, from a distance – from a somewhat ironic distance. In this way the poet is able to present himself as “the other”, thus referring to the title of Paul Ricoeur’s book.2177925Przestrzenie Teori

The adipocyte component of bone marrow in heterotopic bone induced by demineralized incisor grafts

The relative proportion of adipocytes to hematopoietic elements in the marrow of heterotopicallyinduced bone evaluated 4–42 weeks post implantation of demineralized murine incisors was estimated by histologicalanalysis of hematoxylin-eosin stained tissue sections. Using computerized image analysis of microphotographs,the proportion of nuclear cells vs. adipocytes was ascertained. The percentage of adipocytes in marrowincreases over time. Such an effect, the replacement of myelopoietic marrow by adipogenic (yellow) marrowand the resorption of induced bone, is observed in human osteoporosis. A decline in the non-adipogenic cellcompartments of bone marrow accompanying induced bone begins in the fourth week of induction, graduallyprogresses until the 26th week, and does not change after that. The luminosity, a parameter used in image analysisand proportional to the number of nuclear cells, was 124 ± 3 in hematopoietic femoral bone marrow, andthat of bone marrow of the induced bone was of a similar value (117 ± 8) in the fourth week. An evident declinein luminosity of bone marrow filling the foci of heterotopic bone was observed in samples taken at nine weeks(82 ± 20). This process progressed until the 26th week, reaching a luminosity of 70 ± 21. At the 42nd week, theluminosity remained at the same level (71 ± 27). This indicates that the replacement of hematopoietic bonemarrow of heterotopically induced bone by unilocular adipocytes begins relatively early (the fourth week) and ispersistent.The relative proportion of adipocytes to hematopoietic elements in the marrow of heterotopicallyinduced bone evaluated 4–42 weeks post implantation of demineralized murine incisors was estimated by histologicalanalysis of hematoxylin-eosin stained tissue sections. Using computerized image analysis of microphotographs,the proportion of nuclear cells vs. adipocytes was ascertained. The percentage of adipocytes in marrowincreases over time. Such an effect, the replacement of myelopoietic marrow by adipogenic (yellow) marrowand the resorption of induced bone, is observed in human osteoporosis. A decline in the non-adipogenic cellcompartments of bone marrow accompanying induced bone begins in the fourth week of induction, graduallyprogresses until the 26th week, and does not change after that. The luminosity, a parameter used in image analysisand proportional to the number of nuclear cells, was 124 ± 3 in hematopoietic femoral bone marrow, andthat of bone marrow of the induced bone was of a similar value (117 ± 8) in the fourth week. An evident declinein luminosity of bone marrow filling the foci of heterotopic bone was observed in samples taken at nine weeks(82 ± 20). This process progressed until the 26th week, reaching a luminosity of 70 ± 21. At the 42nd week, theluminosity remained at the same level (71 ± 27). This indicates that the replacement of hematopoietic bonemarrow of heterotopically induced bone by unilocular adipocytes begins relatively early (the fourth week) and ispersistent

Dissociable neural correlates of multisensory coherence and selective attention

Previous work has demonstrated that performance in an auditory selective attention task can be enhanced or impaired, depending on whether a task-irrelevant visual stimulus is temporally coherent with a target auditory stream or with a competing distractor. However, it remains unclear how audiovisual (AV) temporal coherence and auditory selective attention interact at the neurophysiological level. Here, we measured neural activity using electroencephalography (EEG) while human participants (men and women) performed an auditory selective attention task, detecting deviants in a target audio stream. The amplitude envelope of the two competing auditory streams changed independently, while the radius of a visual disc was manipulated to control the audiovisual coherence. Analysis of the neural responses to the sound envelope demonstrated that auditory responses were enhanced independently of the attentional condition: both target and masker stream responses were enhanced when temporally coherent with the visual stimulus. In contrast, attention enhanced the event-related response (ERP) evoked by the transient deviants, independently of AV coherence. Finally, in an exploratory analysis, we identified a spatiotemporal component of ERP, in which temporal coherence enhanced the deviant-evoked responses only in the unattended stream. These results provide evidence for dissociable neural signatures of bottom-up (coherence) and top-down (attention) effects in AV object formation.Significance StatementTemporal coherence between auditory stimuli and task-irrelevant visual stimuli can enhance behavioral performance in auditory selective attention tasks. However, how audiovisual temporal coherence and attention interact at the neural level has not been established. Here, we measured EEG during a behavioral task designed to independently manipulate AV coherence and auditory selective attention. While some auditory features (sound envelope) could be coherent with visual stimuli, other features (timbre) were independent of visual stimuli. We find that audiovisual integration can be observed independently of attention for sound envelopes temporally coherent with visual stimuli, while the neural responses to unexpected timbre changes are most strongly modulated by attention. Our results provide evidence for dissociable neural mechanisms of bottom-up (coherence) and top-down (attention) effects on AV object formation

Iron, zinc, copper, manganese and chromium in green teas, their transfer to extracts and correlations between contents of elements and bioactive compounds

Green tea is used worldwide in the preparation of beverages, but also its extracts rich in bioactive compounds, especially flavan-3-ols, are of increasing interest. In addition to bioactive molecules, green tea represents a source of dietary elements. However, knowledge about their content in extracts is limited. The aim of our research was to determine the extent of transfer of selected elements, i.e., iron (Fe), zinc (Zn), copper (Cu), manganese (Mn), and chromium (Cr), from green teas to their extracts and to investigate whether the main bioactive compounds of the extracts affect this transfer. Twelve commercially available green teas were used in the study. The contents of elements in green teas and their extracts obtained with 80% acetone (v/v) were analysed by inductively coupled plasma optical emission spectroscopy (ICP-OES). High performance liquid chromatography in reverse phase (RP-HPLC) was used to determine contents of caffeine, (–)-epigallocatechin (EGC), (–)-epicatechin (EP), (–)-epigallocatechin gallate (EGCG), and (–)-epicatechin gallate (ECG). The element with the highest content in green teas was Mn (711–1402 µg/g), but its transfer to extracts was the lowest (0.269–0.646%). The mean Fe transfer, second abundant element in teas (115–725 µg/g), was 5.52%. The contents of Mn and Fe in extracts were 5.08–30.2 and 10.7–90.1 µg/g, respectively. Zn, Cu, and Cr were transferred with means of 10.4, 20.0, and 26.2%, respectively, which resulted in their contents in the extracts in the ranges of 5.03–12.6, 1.93–13.8, and 0.128–2.03 µg/g, respectively. The significant positive correlations of Zn content in extracts and/or transfer to extracts with EGCG, EGC and total flavan-3-ols as well as between the same Fe variables and EGC were determined, which suggested that these flavan-3-ols may positively affect the transfer of Fe and Zn from green tea to extracts. In turn, significant but negative correlations were found in the case of Mn and Cu. Future research is needed to identify the causes of the various transfer rate of elements from green teas to extracts

Einstein-Podolsky-Rosen paradox without entanglement

We claim that the nonlocality without entanglement revealed quite recently by Bennett {\it et al.} [quant-ph/9804053] should be rather interpreted as {\it Einstein-Podolsky-Rosen paradox without entanglement}. It would be true nonlocality without entanglement if one knew that quantum mechnics provides the best possible means for extracting information from physical system i.e. that it is ``operationally complete''.Comment: RevTeX, 2 page