Hubble Space Telescope Imaging of the Ultracompact Blue Dwarf Galaxy HS 0822+3542: An Assembling Galaxy in a Local Void?

We present deep U, narrow-V, and I-band images of the ultracompact blue dwarf galaxy HS 0822+3542, obtained with the Advanced Camera for Surveys / High Resolution Channel of the Hubble Space Telescope. This object is extremely metal-poor (12 + log(O/H) = 7.45) and resides in a nearby void. The images resolve it into two physically separate components that were previously described as star clusters in a single galaxy. The primary component is only \~100 pc in maximum extent, and consists of starburst region surrounded by a ring-like structure of relatively redder stars. The secondary component is ~50 pc in size and lies at a projected distance of ~80 pc away from the primary, and is also actively star-forming. We estimate masses ~10^7 M(sol) and ~10^6 M(sol) for the two components, based on their luminosities, with an associated dynamical timescale for the system of a few Myr. This timescale and the structure of the components suggests that a collision between them triggered their starbursts. The spectral energy distributions of both components can be fitted by the combination of recent (few Myr old) starburst and an evolved (several Gyr old) underlying stellar population, similar to larger blue compact dwarf galaxies. This indicates that despite its metal deficiency the object is not forming its first generation of stars. However, the small sizes and masses of the two components suggests that HS 0822+3542 represents a dwarf galaxy in the process of assembling from clumps of stars intermediate in size between globular clusters and objects previously classified as galaxies. Its relatively high ratio of neutral gas mass to stellar mass (~1) and high specific star formation rate, log(SFR/M(sol) = -9.2, suggests that it is still converting much of its gas to stars.Comment: 11 pages, 2 figures, accepted for publication in Astrophysical Journal Letter

An Exploration of Home Attachment Representations using an Adaptation of Adult Attachment Interview: Preliminary Data on the Home Attachment Interview

Background: In analysing the literature on household as a physical structure strongly linked to cultural and affective aspects, as well as to universal central psychological needs, a universe of meanings was found. The household, conceptualised as home and safe shelter that contains and protects, but also as a favourite place where the most important relationships of each human being unfold, suggests to use attachment theory perspective as a potentially useful framework to conceptualize the construct of home attachment. However, this perspective needs to be further investigated in order to understand its complex nature. Therefore, this pilot study aims to investigate how individuals represent their own homes according to their feelings and emotions related to their household.Methods: A qualitative-quantitative survey has been carried out with 50 adults (50% females) divided into five different age groups (from late adolescence to old age). An adapted version of the Adult Attachment Interview, the Home Attachment Interview, was administered.Results: Analysis identified the relevant aspects that distinguish the "house" as a physical structure, and the "home", that symbolically encloses emotional and affective experiences suggesting a perception of the "house" as "home", being a special place characterised by a strong attachment relationship connoted symbolically and affectively.Conclusions: Attachment theoretical and methodological tools used in the study appear especially useful to investigate and understand the construct of home attachment

Harnessing post-translational modifications for next-generation HIV immunogens

The extensive post-translational modifications of the envelope spikes of the human immunodeficiency virus (HIV) present considerable challenges and opportunities for HIV vaccine design. These oligomeric glycoproteins typically have over 30 disulfide bonds and around a 100 N-linked glycosylation sites, and are functionally dependent on protease cleavage within the secretory system. The resulting mature structure adopts a compact fold with the vast majority of its surface obscured by a protective shield of glycans which can be targeted by broadly neutralizing antibodies (bnAbs). Despite the notorious heterogeneity of glycosylation, rare B-cell lineages can evolve to utilize and cope with viral glycan diversity, and these structures therefore present promising targets for vaccine design. The latest generation of recombinant envelope spike mimetics contains re-engineered post-translational modifications to present stable antigens to guide the development of bnAbs by vaccination

Hubble Space Telescope Counts of Elliptical Galaxies: Constraints on Cosmological Models ?

The interpretation of galaxy number counts in terms of cosmological models is fraught with difficulty due to uncertainties in the overall galaxy population (mix of morphological types, luminosity functions etc.) and in the observations (loss of low surface brightness images, image blending etc.). Many of these can be overcome if we use deep high resolution imaging of a single class of high surface brightness galaxies, whose evolution is thought to be fairly well understood. This is now possible by selecting elliptical and S0 galaxies using Hubble Space Telescope images from the Medium Deep Survey and other ultradeep WFPC2 images. In the present paper, we examine whether such data can be used to discriminate between open and closed universes, or between conventional cosmological models and those dominated by a cosmological constant. We find, based on the currently available data, that unless elliptical galaxies undergo very strong merging since $z \sim 1$ (and/or very large errors exist in the morphological classifications), then flat models dominated by a cosmological constant are ruled out. However, both an Einstein-de Sitter ($\Omega_{0}=1$) model with standard passive stellar evolution and an open ($\Omega_{0}=0.05$) model with no net evolution ({\it i.e.} cancelling stellar and dynamical evolution) predict virtually identical elliptical and S0 galaxy counts. Based on these findings and the recent reportings of $H_{o} \simeq 80$ km/s Mpc/s, we find that the maximum acceptable age of the universe is 13.3 Gyrs and a value of $\leq 9$ Gyrs favored. A flat---$\Lambda \neq 0$---universe is therefore {\it not} a viable solution to the $H_{o}$/globular cluster age problem.Comment: Accepted for publication in the Astrophysical Journal (April, 1996). 34 pages (including 4 figures) of gzip compressed and uuencoded PS. Also available at http://www.phys.unsw.edu.au/~spd/bib.htm

Compact Lyman-alpha Emitting Candidates at z~2.4 in Deep Medium-band HST WFPC2 Images

Medium-band imaging with HST/WFPC2 in the F410M filter has previously revealed a population of compact Lyman-alpha emission objects around the radio galaxy 53W002 at z~2.4. We report detections of similar objects at z~2.4 in random, high-latitude HST parallel observations of three additional fields, lending support to the idea that they constitute a widespread population at these redshifts. The three new fields contain 18 Lyman-alpha candidates, in contrast to the 17 detected in the deeper exposure of the single WFPC2 field around 53W002. We find substantial differences in the number of candidates from field to field, suggesting that significant large-scale structure is already present in the galaxy distribution at this cosmic epoch. The likely existence of z~2.4 sub-galactic clumps in several random fields shows that these objects may have been common in the early universe and strengthens the argument that such objects may be responsible for the formation of a fraction of the luminous present-day galaxies through hierarchical merging.Comment: Uses slightly modified AASTeX preprint style file (included). Contains 22 pages, including 5 figures and 2 tables. Accepted for the December issue of the Astronomical Journa

Feasibility of a Manualized Mindful Yoga Intervention for Patients With Chronic Mood Disorders

Chronic mood disorders pose an important mental health problem. Individuals with these disorders experience a significant impairment, often fail to seek help, and their illnesses frequently do not respond to treatment. It is therefore important to develop innovative and attractive treatments for these disorders. Mindful yoga represents a promising treatment approach. This pilot study tested the feasibility of a 9-week manualized mindful yoga intervention for patients with chronic mood disorders. Eleven patients receiving standard treatment were recruited to complete a 9-week mindful yoga intervention. Qualitative methods were used to assess patients' experiences of the intervention and quantitative methods were used to assess psychological distress and mechanisms that play a role in chronic mood disorders. Eight patients completed the intervention and rated the overall quality of the intervention with a mean score of 8.8 (range of 8 to 9, using a scale of 1 to 10). All participants reported a reduction in psychological distress and no adverse events. Among the mechanisms that play a role in chronic mood disorders, the most potentially promising effects from the intervention were found for worry, fear of depression and anxiety, rumination, and areas related to body awareness, such as trusting bodily experiences and not distracting from sensations of discomfort. A 9-week mindful yoga intervention appears to be a feasible and attractive treatment when added to treatment as usual for a group of patients with chronic mood disorders. A randomized controlled trial to study the effects of mindful yoga is recommended

Analysis of monotonic greening and browning trends from global NDVI time-series

Remotely sensed vegetation indices are widely used to detect greening and browning trends; especially the global coverage of time-series normalized difference vegetation index (NDVI) data which are available from 1981. Seasonality and serial auto-correlation in the data have previously been dealt with by integrating the data to annual values; as an alternative to reducing the temporal resolution, we apply harmonic analyses and non-parametric trend tests to the GIMMS NDVI dataset (1981-2006). Using the complete dataset, greening and browning trends were analyzed using a linear model corrected for seasonality by subtracting the seasonal component, and a seasonal non-parametric model. In a third approach, phenological shift and variation in length of growing season were accounted for by analyzing the time-series using vegetation development stages rather than calendar days. Results differed substantially between the models, even though the input data were the same. Prominent regional greening trends identified by several other studies were confirmed but the models were inconsistent in areas with weak trends. The linear model using data corrected for seasonality showed similar trend slopes to those described in previous work using linear models on yearly mean values. The non-parametric models demonstrated the significant influence of variations in phenology; accounting for these variations should yield more robust trend analyses and better understanding of vegetation trends