The interaction of class and gender in illness narratives

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2008 BSA Publications Ltd.Perspectives on gender and identity that emphasize variability of performance, local context and individual agency have displaced earlier paradigms.These are now perceived to have supported gender stereotypes and language ideologies by emphasizing gender difference and homogeneity within genders. In a secondary analysis of health and illness narratives we explore the interaction of class and gender in individuals' constructions of gendered identity. High social class men perform gender in particularly varied ways and we speculate that this variable repertoire, including the use of what was once termed `women's language', is linked to a capacity to maintain social distinction and authority. Men's performance of conventional masculinity is often threatened by both the experience of illness and being interviewed about personal experience. Lower social class women in particular demonstrate an intensification of a pre-existing informal family and support group culture, marking successful members by awarding them the accolade of being `lovely'.ESR

The Life and Death of Dense Molecular Clumps in the Large Magellanic Cloud

We report the results of a high spatial (parsec) resolution HCO+ (J = 1-0) and HCN (J = 1-0) emission survey toward the giant molecular clouds of the star formation regions N105, N113, N159, and N44 in the Large Magellanic Cloud. The HCO+ and HCN observations at 89.2 and 88.6 GHz, respectively, were conducted in the compact configuration of the Australia Telescope Compact Array. The emission is imaged into individual clumps with masses between 10^2 and 10^4 solar masses and radii of <1 pc to ~2 pc. Many of the clumps are coincident with indicators of current massive star formation, indicating that many of the clumps are associated with deeply-embedded forming stars and star clusters. We find that massive YSO-bearing clumps tend to be larger (>1 pc), more massive (M > 10^3 solar masses), and have higher surface densities (~1 g cm^-2), while clumps without signs of star formation are smaller (<1 pc), less massive (M < 10^3 solar masses), and have lower surface densities (~0.1 g cm^-2). The dearth of massive (M >10^3 solar masses) clumps not bearing massive YSOs suggests the onset of star formation occurs rapidly once the clump has attained physical properties favorable to massive star formation. Using a large sample of LMC massive YSO mid-IR spectra, we estimate that ~2/3 of the massive YSOs for which there are Spitzer mid-IR spectra are no longer located in molecular clumps; we estimate that these young stars/clusters have destroyed their natal clumps on a time scale of at least 3 x 10^{5}$ yrs.Comment: Accepted to ApJ 3-19-201

Spitzer View of Massive Star Formation in the Tidally Stripped Magellanic Bridge

The Magellanic Bridge is the nearest low-metallicity, tidally stripped environment, offering a unique high-resolution view of physical conditions in merging and forming galaxies. In this paper we present analysis of candidate massive young stellar objects (YSOs), i.e., {\it in situ, current} massive star formation (MSF) in the Bridge using {\it Spitzer} mid-IR and complementary optical and near-IR photometry. While we definitely find YSOs in the Bridge, the most massive are $\sim10 M_\odot$, $\ll45 M_\odot$ found in the Large Magellanic Cloud (LMC). The intensity of MSF in the Bridge also appears decreasing, as the most massive YSOs are less massive than those formed in the past. To investigate environmental effects on MSF, we have compared properties of massive YSOs in the Bridge to those in the LMC. First, YSOs in the Bridge are apparently less embedded than in the LMC: 81% of Bridge YSOs show optical counterparts, compared to only 56% of LMC sources with the same range of mass, circumstellar dust mass, and line-of-sight extinction. Circumstellar envelopes are evidently more porous or clumpy in the Bridge's low-metallicity environment. Second, we have used whole samples of YSOs in the LMC and the Bridge to estimate the probability of finding YSOs at a given \hi\ column density, N(HI). We found that the LMC has $\sim3\times$ higher probability than the Bridge for N(HI) $>10\times10^{20}$ cm$^{-2}$, but the trend reverses at lower N(HI). Investigating whether this lower efficiency relative to HI is due to less efficient molecular cloud formation, or less efficient cloud collapse, or both, will require sensitive molecular gas observations.Comment: 41 pages, 20 figures, 6 tables; accepted for publication in ApJ; several figures are in low resolution due to the size limit here and a high resolution version can be downloaded via http://www.astro.virginia.edu/~cc5ye/ms_bridge20140215.pd

Leptin Stimulates Cellular Glycolysis Through a STAT3 Dependent Mechanism in Tilapia

We assessed if leptin, a cytokine hormone known to enhance energy expenditure by promoting lipid and carbohydrate catabolism in response to physiologic stress, might directly regulate cellular glycolysis. A transcriptomic analysis of prolactin cells in the tilapia (Oreochromis mossambicus) pituitary rostral pars distalis (RPD) revealed that recombinant leptin (rtLep) differentially regulates 1,995 genes, in vitro. Machine learning algorithms and clustering analyses show leptin influences numerous cellular gene networks including metabolism; protein processing, transport, and metabolism; cell cycle and the hypoxia response. Leptin stimulates transcript abundance of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (gapdh) in a covariate manner to the hypoxic stress gene network. Orthogonal tests confirm that rtLepA dose-dependently increases gapdh gene expression in the RPD along with transcript abundance of 6-phosphofructo-1-kinase (pfk1), the rate limiting glycolytic enzyme. Functional testing demonstrated that leptin stimulates PFK activity and glycolytic output, while Stattic (a STAT3 blocker) was sufficient to suppress these responses, indicating leptin stimulates glycolysis through a STAT3-dependent mechanism. Leptin also stimulated pfk1 gene expression and lactate production in primary hepatocyte incubations in a similar manner to those shown for the pituitary RPD. This work characterizes a critical metabolic action of leptin to directly stimulate glycolysis across tissue types in a teleost model system, and suggest that leptin may promote energy expenditure, in part, by stimulating glycolysis. These data in a teleost fish, suggest that one of leptin's ancient, highly-conserved functions among vertebrates may be stimulation of glycolysis to facilitate the energetic needs associated with various stressors

Spitzer View of Young Massive Stars in the LMC HII Complexes. II. N159

The HII complex N159 in the Large Magellanic Cloud (LMC) is used to study massive star formation in different environments, as it contains three giant molecular clouds (GMCs) that have similar sizes and masses but exhibit different intensities of star formation. We identify candidate massive young stellar objects (YSOs) using infrared photometry, and model their SEDs to constrain mass and evolutionary state. Good fits are obtained for less evolved Type I, I/II, and II sources. Our analysis suggests that there are massive embedded YSOs in N159B, a maser source, and several ultracompact HII regions. Massive O-type YSOs are found in GMCs N159-E and N159-W, which are associated with ionized gas, i.e., where massive stars formed a few Myr ago. The third GMC, N159-S, has neither O-type YSOs nor evidence of previous massive star formation. This correlation between current and antecedent formation of massive stars suggests that energy feedback is relevant. We present evidence that N159-W is forming YSOs spontaneously, while collapse in N159-E may be triggered. Finally, we compare star formation rates determined from YSO counts with those from integrated H-alpha and 24 micron luminosities and expected from gas surface densities. Detailed dissection of extragalactic GMCs like the one presented here is key to revealing the physics underlying commonly used star formation scaling laws.Comment: 60 pages, 11 figures. Accepted for publication in Astrophysical Journa

SPITZER VIEW OF YOUNG MASSIVE STARS IN THE LARGE MAGELLANIC CLOUD H II COMPLEXES. II. N 159

The H II complex N 159 in the Large Magellanic Cloud is used to study massive star formation in different environments, as it contains three giant molecular clouds (GMCs) that have similar sizes and masses but exhibit different intensities of star formation. We identify candidate massive young stellar objects (YSOs) using infrared photometry, and model their spectral energy distributions to constrain mass and evolutionary state. Good fits are obtained for less evolved Type I, I/II, and II sources. Our analysis suggests that there are massive embedded YSOs in N 159B, a maser source, and several ultracompact H II regions. Massive O-type YSOs are found in GMCs N 159-E and N 159-W, which are associated with ionized gas, i.e., where massive stars formed a few Myr ago. The third GMC, N 159-S, has neither O-type YSOs nor evidence of previous massive star formation. This correlation between current and antecedent formation of massive stars suggests that energy feedback is relevant. We present evidence that N 159-W is forming YSOs spontaneously, while collapse in N 159-E may be triggered. Finally, we compare star formation rates determined from YSO counts with those from integrated H{alpha} and 24 {mu}m luminosities and expected from gas surfacemore » densities. Detailed dissection of extragalactic GMCs like the one presented here is key to revealing the physics underlying commonly used star formation scaling laws.« les

The while of participation: A systematic review of participatory research involving people with sensory impairments and/or intellectual impairments.

This paper reports on the first systematic review of literature associated with participatory research involving people identified with sensory impairments and/or intel- lectual impairments. It was initiated as part of ARCHES, an European Union-funded heritage project. The review sought to examine processes and activities used for organising participatory research involving people identified with sensory and/or intellectual impairments. 54 papers were included, involving studies from 14 countries and varying numbers of participants across different time scales. Insights were gained into use of advisory groups, organisation and support, collecting and analysing data, sharing findings and activity types. Emergent themes enabled an identification of the while of participation. The while represents the tensions, outcomes and component parts which are evident within the multiple moments that span an experience of participatory research. Participation is not about types of activity but how any activity is undertaken

The Evolution Of Massive Young Stellar Objects in the Large Magellanic Cloud. I. Identification and Spectral Classification

We present and categorize Spitzer infrared spectrometer spectra of 294 objects in the Large Magellanic Cloud (LMC) to create the largest and most complete catalog of massive young stellar object (YSO) spectra in the LMC. Target sources were identified from infrared photometry and multiwavelength images indicative of young, massive stars highly enshrouded in their natal gas and dust clouds. Several objects have been spectroscopically identified as non-YSOs and have features similar to more-evolved stars such as red supergiants, asymptotic giant branch (AGB), and post-AGB stars. Our sample primarily consists of 277 objects we identify as having spectral features indicative of embedded YSOs. The remaining sources are comprised of seven C-rich evolved sources, eight sources dominated by broad silicate emission, and one source with multiple broad emission features. Those with YSO-like spectra show a range of spectral features including polycyclic aromatic hydrocarbon emission, deep silicate absorption, fine-structure lines, and ice absorption features. Based upon the relative strengths of these features, we have classified the YSO candidates into several distinct categories using the widely used statistical procedure known as principal component analysis. We propose that these categories represent a spectrum of evolutionary stages during massive YSO formation. Using our catalog we put statistical constraints on the relative evolutionary timescale of processes involved in massive star formation. We conclude that massive pre-main-sequence stars spend a majority (possibly as high as 90%) of their massive, embedded lives emitting in the UV. Half of the sources in our study have features typical of compact H II regions, suggesting that massive YSOs can create a detectable compact H II region half-way through the formation time present in our sample. This study also provides a check on commonly used source-selection procedures including the use of photometry to identify YSOs. We determine that a high success rate (>95%) of identifying objects with YSO-like spectra can be achieved through careful use of infrared color-magnitude diagrams, spectral energy distributions, and image inspections

The Evolution of Massive YSOs in the LMC: Part I. Identification and Spectral Classification

We present and categorize Spitzer IRS spectra of 294 objects in the Large Magellanic Cloud (LMC) to create the largest and most complete catalog of massive young stellar object (YSO) spectra in the LMC. Target sources were identified from infrared photometry and multi-wavelength images indicative of young, massive stars highly enshrouded in their natal gas and dust clouds. Our sample primarily consists of 277 objects we identify as having spectral features indicative of embedded YSOs. The remaining sources are comprised of 7 C-rich evolved sources, 8 sources dominated by broad silicate emission, and 1 source with multiple broad emission features. Those with YSO-like spectra show a range of spectral features including polycyclic aromatic hydrocarbon emission, deep silicate absorption, fine-structure lines, and ice absorption features. Based upon the relative strengths of these features, we have classified the YSO candidates into several distinct categories using the widely-used statistical procedure known as principal component analysis. We propose that these categories represent a spectrum of evolutionary stages during massive YSO formation. We conclude that massive pre-main sequence stars spend a majority of their massive, embedded lives emitting in the UV. Half of the sources in our study have features typical of compact HII regions, suggesting that massive YSOs can create a detectable compact HII region half-way through the formation time present in our sample. This study also provides a check on commonly used source-selection procedures including the use of photometry to identify YSOs. We determine a high success rate (>95%) of identifying objects with YSO-like spectra can be achieved through careful use of infrared CMDs, SEDs, and image inspections.Comment: Accepted to The Astrophysical Journa