Food Allergies Abroad: An Exploration of the Experiences Individuals with Food Allergies Face While Studying Abroad

Food allergies are a life-threatening medical condition that can result in a potentially fatal allergic reaction known as anaphylaxis. Food allergies affect roughly 15 million United States citizens and this number is growing, currently there is no cure. Young adults are most at risk to experience this life-threatening reaction. As more students with food allergies are entering colleges and universities to pursue a higher education, they are also becoming increasingly interested in studying abroad; however, there are few resources available. This research paper aims to explore the various challenges those with food allergies experience while studying abroad. To understand these challenges, we will first look at various laws surrounding food allergy accommodations and what institutions of higher education are doing in response to the growing number of students with food allergies. We will also explore research that has been done regarding traveling with food allergies and studying abroad with chronic illness. It became apparent that little research has been done specifically on studying abroad with food allergies. In this research, sixteen individuals with life-threatening food allergies participated in a survey where they recounted their experiences managing their food allergies while abroad. Of the sixteen, six participants agreed to a follow-up interview where they recounted in detail their experiences

Master of Science

thesisCurrently, identification of proximal risk factors of suicide is a primary focus of suicide research; however, knowledge of these risk factors is limited. Therefore, longitudinal studies aiming to identify proximal, time-varying predictors of suicidal behavior are needed to improve prediction and prevention of suicide behaviors. To date, several studies have reported significant associations among insomnia, suicide ideation, and suicidal behaviors. This study sought to examine the relationship between insomnia (ISI) and suicide risk (BSS) over time amongst a group of suicide ideators, single, and multiple suicide attempters who took part in a clinical trial comparing treatment as usual (TAU) to brief cognitive behavioral therapy (BCBT). Participants included 152 active-duty Army soldiers reporting past week suicide ideation with some intent and/or past month suicide attempt. Longitudinal growth modeling was used to test the effect of trajectories of variables, as well as to compare group means. Additionally, a two-intercept cross-lagged panel over time was created to determine if insomnia and suicide scores risk predict change at the next time point. BCBT participants experienced a significant negative trajectory of ISI, while TAU's trajectory was nonsignificant. Suicide ideators and single attempters reported similar baseline and end-of-study levels of ISI. No differences in ISI trajectories were observed between suicide status groups. A two-intercept cross-lagged panel over time was created to model the ability of previous BSS and ISI scores to predict change in the following time points. Previous variable measurements (t-1) significantly predicted change in following like-measurements, but did not predict change in the other variable (i.e., t-1 ISI did not predict change in BSS, t-1 BSS did not predict change in ISI). Results of analyses revealed that suicide status groups report similar baseline levels of insomnia and suicide risk; suicide status groups have similar trajectories in insomnia over time; and while insomnia and suicide risk change together over time, change in one does not predict change in the other. Overall, these findings suggest that insomnia is a co-occurring problem with suicide risk for individuals with suicidal thoughts and behaviors, but it does not influence fluctuations in suicide risk

A study of participation in the Eastern Massachusetts Chapter of National Association of Social Workers

Thesis (M.S.)--Boston Universit

Probing the role of Nd3+ ions in the weak multiferroic character of NdMn2O5 by optical spectroscopies

Raman and infrared spectroscopies are used as local probes to study the dynamics of the Nd-O bonds in the weakly multiferroic NdMn2O5 system. The temperature dependence of selected Raman excitations reveals the splitting of the Nd-O bonds in NdMn2O5. The Nd3+ ion crystal field (CF) excitations in NdMn2O5 single crystals are studied by infrared transmission as a function of temperature, in the 1800-8000 cm-1 range, and under an applied magnetic field up to 11 T. The frequencies of all 4Ij crystal-field levels of Nd3+ are determined. We find that the degeneracy of the ground-state Kramers doublet is lifted ({\Delta}0 ~7.5 cm-1) due to the Nd3+-Mn3+ interaction in the ferroelectric phase, below TC ~ 28 K. The Nd3+ magnetic moment mNd(T) and its contribution to the magnetic susceptibility and the specific heat are evaluated from {\Delta}0(T) indicating that the Nd3+ ions are involved in the magnetic and the ferroelectric ordering observed below ~ 28 K. The Zeeman splitting of the excited crystal field levels of the Nd3+ ions at low temperature is also analyzed.Comment: This paper is accepted for publication as a Regular Article in Physical Review

Optical Coronagraphic Spectroscopy of AU Mic: Evidence of Time Variable Colors?

We present coronagraphic long slit spectra of AU Mic's debris disk taken with the STIS instrument aboard the Hubble Space Telescope (HST). Our spectra are the first spatially resolved, scattered light spectra of the system's disk, which we detect at projected distances between approximately 10 and 45 AU. Our spectra cover a wavelength range between 5200 and 10200 angstroms. We find that the color of AU Mic's debris disk is bluest at small (12-35 AU) projected separations. These results both confirm and quantify the findings qualitatively noted by Krist et al. (2005), and are different than IR observations that suggested a uniform blue or gray color as a function of projected separation in this region of the disk. Unlike previous literature that reported the color of AU Mic's disk became increasingly more blue as a function of projected separation beyond approximately 30 AU, we find the disk's optical color between 35-45 AU to be uniformly blue on the southeast side of the disk and decreasingly blue on the northwest side. We note that this apparent change in disk color at larger projected separations coincides with several fast, outward moving "features" that are passing through this region of the southeast side of the disk. We speculate that these phenomenon might be related, and that the fast moving features could be changing the localized distribution of sub-micron sized grains as they pass by, thereby reducing the blue color of the disk in the process. We encourage follow-up optical spectroscopic observations of the AU Mic to both confirm this result, and search for further modifications of the disk color caused by additional fast moving features propagating through the disk.Comment: Accepted by AJ, 13 pages, 8 figures, 1 tabl

HST-STIS Spatially Resolved Spectroscopy and Coronagraphic Imaging of the TW Hydrae Circumstellar Disk

We present the first spatially resolved spectrum of scattered light from the TW Hydrae protoplanetary disk. This nearly face-on disk is optically thick, surrounding a classical T Tauri star in the nearby 10 Myr old TW Hya association. The spectrum was taken with the HST-STIS CCD, providing resolution R ~ 360 over the wavelength range 5250 - 10300 A. Spatially resolved spectroscopy of circumstellar disks is difficult due to the high contrast ratio between the bright star and faint disk. Our novel observations provide optical spectra of scattered light from the disk between 40 AU and 155 AU from the star. The scattered light has the same color as the star (gray scattering) at all radii, except the innermost region. This likely indicates that the scattering dust grains are larger than about 1 micron all the way out to large radii. From the spectroscopic data, we also obtained radial profiles of the integrated disk brightness at two position angles, over almost the same region as previously observed in HST-WFPC2 and NICMOS coronagraphic images (35 AU to 173 AU from the star). The profiles have the same shape as the earlier ones, but show a small azimuthal asymmetry in the disk not previously noted. Our STIS broad-band coronagraphic images of TW Hya confirm the reality of this asymmetry, and show that the disk surface brightness interior to 140 AU has a sinusoidal dependence on azimuthal angle. The maximum brightness occurs at a position angle of 233.6 +/- 5.7 degrees East of North. This might be caused by the combination of forward-scattering and an increase in inclination in the inner region of the disk, suggesting that the TW Hya disk has a warp like that seen in the Beta Pictoris debris disk.Comment: 18 pages, 9 figures (some in color). First version submitted to ApJ 2004-08-29, posted to astro-ph 2004-10-10. Revised version accepted for publication in ApJ 2004-12-07, posted to astro-ph 2004-12-0

The Carbon-Rich Gas in the Beta Pictoris Circumstellar Disk

The edge-on disk surrounding the nearby young star Beta Pictoris is the archetype of the "debris disks", which are composed of dust and gas produced by collisions and evaporation of planetesimals, analogues of Solar System comets and asteroids. These disks provide a window on the formation and early evolution of terrestrial planets. Previous observations of Beta Pic concluded that the disk gas has roughly solar abundances of elements [1], but this poses a problem because such gas should be rapidly blown away from the star, contrary to observations of a stable gas disk in Keplerian rotation [1, 2]. Here we report the detection of singly and doubly ionized carbon (CII, CIII) and neutral atomic oxygen (OI) gas in the Beta Pic disk; measurement of these abundant volatile species permits a much more complete gas inventory. Carbon is extremely overabundant relative to every other measured element. This appears to solve the problem of the stable gas disk, since the carbon overabundance should keep the gas disk in Keplerian rotation [3]. New questions arise, however, since the overabundance may indicate the gas is produced from material more carbon-rich than the expected Solar System analogues.Comment: Accepted for publication in Nature. PDF document, 12 pages. Supplementary information may be found at http://www.dtm.ciw.edu/akir/Documents/roberge_supp.pdf *** Version 2 : Removed extraneous publication information, per instructions from the Nature editor. No other changes mad

Radial Surface Density Profiles of Gas and Dust in the Debris Disk around 49 Ceti

We present ~0.4 resolution images of CO(3-2) and associated continuum emission from the gas-bearing debris disk around the nearby A star 49 Ceti, observed with the Atacama Large Millimeter/Submillimeter Array (ALMA). We analyze the ALMA visibilities in tandem with the broad-band spectral energy distribution to measure the radial surface density profiles of dust and gas emission from the system. The dust surface density decreases with radius between ~100 and 310 au, with a marginally significant enhancement of surface density at a radius of ~110 au. The SED requires an inner disk of small grains in addition to the outer disk of larger grains resolved by ALMA. The gas disk exhibits a surface density profile that increases with radius, contrary to most previous spatially resolved observations of circumstellar gas disks. While ~80% of the CO flux is well described by an axisymmetric power-law disk in Keplerian rotation about the central star, residuals at ~20% of the peak flux exhibit a departure from axisymmetry suggestive of spiral arms or a warp in the gas disk. The radial extent of the gas disk (~220 au) is smaller than that of the dust disk (~300 au), consistent with recent observations of other gas-bearing debris disks. While there are so far only three broad debris disks with well characterized radial dust profiles at millimeter wavelengths, 49 Ceti's disk shows a markedly different structure from two radially resolved gas-poor debris disks, implying that the physical processes generating and sculpting the gas and dust are fundamentally different.Comment: 20 pages, 8 figures, accepted for publication in ApJ March 31, 2017 (submitted Nov 2016

Design, manufacture, and application of DNA microarrays to study gene expression phenotypes of lysine-producing Corynebacterium glutamicum

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2005.Includes bibliographical references (leaves 197-213).Corynebacterium glutamicum partial genome DNA microarrays were constructed that were capable of assaying the transcriptional profile of the genes of pathways involved in central carbon metabolism and lysine biosynthesis. It was found that to ensure arrays of high quality, protocols applying the arrays should include DNase treatment of RNA samples. additional RNA filtration purification steps, and the use of gene specific primers in the formation of labeled cDNA through reverse transcription. After implementing these procedures, the accuracy and reproducibility of the array data were validated. The microarrays were used to explore the effects of the over-expression of the key anaplerotic enzyme pyruvate carboxylase and the use of different medium carbon source compositions, both of which have been shown to influence the yields of biomass on carbon and of lysine on biomass. Three different strains of C. glutamicum that were grown on six different minimal medium formulations that varied in their balance of glucose and lactate were assayed by isolating total mRNA samples from cultures in three different phases of growth and lysine production. Genes associated with glycolysis and the pentose phosphate pathway showed decreased transcript concentrations as the available carbon source was shifted from glucose to lactate, while those associated with the TCA cycle and the glyoxylate bypass demonstrated increased transcription. As the cultures stopped generating biomass and began generating lysine, mRNA of genes associated with lysine synthesis and export was measured at elevated concentrations.(cont.) Reduced gene expression trends seen for aspartokinase and aspartate semialdehyde dehydrogenase suggest that the enzymes are bottlenecks to lysine production, particularly when pyruvate carboxylase is over-expressed and lactate is the available carbon source. This over-expressing strain also had higher transcription levels of the genes of biotin synthesis. and lower transcription levels of the acyl-coA carboxylases dtsRl, dtsR2, accC, and accD. Other results implied that malic enzyme is co-expressed with pyruvate carboxylase to better allow cultures grown on lactate to produce NADPH in the absence of significant pentose phosphate pathway flux. Also, the transcriptional and flux profiles of a pair of C. glutamicum strains grown on two different medium compositions of isotopically labeled glucose and lactate were determined simultaneously from the same set of actively growing and lysine-producing cultures. Flux maps for each of the four combinations of strain and medium were constructed using calculations derived from metabolite balances and GC-MS measurements of the isotopic distributions within biomass hydrolysates of the pseudo-steady-state cultures. Comparisons of the two sets of data showed that 19 of 28 pairs of flux and transcription measurements had trends with good agreement with one another. Different pathways of the metabolic network were found to be controlled via transcription in varying degrees. On average, the Embden- Meyerhof-Parnas pathway was shown to be less likely to be regulated though transcription than the pathways of the tricarboxylic acid cycle and central carbon anaplerosis.(cont.) In the split pathway available to the cells for producing lysine, the succinylation branch showed an increase in flux for only the case of a pyruvate carboxylase over-expressing strain that was grown on lactate, while the alternate dehydrogenation branch showed a complementary decrease in flux. These flux changes were matched by changes in transcription that only occurred for the same culture and growth medium. Through these findings we have demonstrated the application of C. glutamicum DNA microarrays to the determination of how the cells regulate their responses at the transcriptional level to changes in both gene over-expression and medium composition.by Christopher Roberge.Ph.D