Biomanufacturing through iGEM-An International Student Competition

The foundations of synthetic biology are built on molecular biology and genetic engineering. One of the purposes of synthetic biology is to make biology easier to engineer by the creation of standardized biological parts and devices. There are a wide range of potential applications for synthetic biology and a variety of approaches to constructing parts and systems. Undergraduate Science, Technology, Engineering, and Mathematics (STEM) students from around the world apply synthetic biology principles at the annual International Genetically Engineered Machine (iGEM) competition to demonstrate functioning biological systems created from standardized parts. The iGEM competition will continue to add to the growing field of synthetic biology and the global bioeconomy through innovations in projects and training of STEM students. In this study, a survey was conducted of the iGEM team participants at the 2014 competition, specifically to investigate teams that had biomanufacturing as the foundation for their projects. Teams that participated during the 2014 iGEM competition comprised of STEM undergraduate and graduate students from different geographical regions. The primary source of information for this study was from 2014 iGEM team websites. The results of this study found that many student-led teams are able to build on the fundamentals of synthetic biology to generate a wide range of useful bioproducts. In doing so, students are training themselves for future careers in STEM and expanding the field of synthetic biology

Enhanced Polyhydroxybutyrate Production for Long-Term Spaceflight Applications

Synthetic biology holds the promise of advancing long term space fight by the production of medicine, food, materials, and energy. One such application of synthetic biology is the production of biomaterials, specifically polyhydroxyalkanoates (PHAs), using purposed organisms such as Escherichia coli. PHAs are a group of biodegradable bioplastics that are produced by a wide variety of naturally occurring microorganisms, mainly as an energy storage intermediate. PHAs have similar melting point to polypropylene and a Youngs modulus close to polystyrene. Due to limited resources and cost of transportation, large-scale extraction of biologically produced products in situ is extremely cumbersome during space flight. To that end, we are developing a secretion systems for exporting PHA from the cell in order to reduce unit operations. PHAs granules deposited inside bacteria are typically associated with proteins bound to the granule surface. Phasin, a granule bound protein, was targeted for type I secretion by fusion with HlyA signal peptide for indirect secretion of PHAs. In order to validate our secretion strategy, a green fluorescent protein (GFP) was tagged to the PHA polymerase enzyme (phaC), this three part gene cassette consists of phaA and phaB and are required for PHA production. Producing PHAs in situ during space flight or planet colonization will enable mission success by providing a valuable source of biomaterials that can have many potential applications thereby reducing resupply requirements. Biologically produced PHAs can be used in additive manufacturing such as three dimensional (3D) printing to create products that can be made on demand during space flight. After exceeding their lifetime, the PHAs could be melted and recycled back to 3D print other products. We will discuss some of our long term goals of this approach

A Gaseous Group with Unusual Remote Star Formation

We present VLA 21-cm observations of the spiral galaxy ESO 481-G017 to determine the nature of remote star formation traced by an HII region found 43 kpc and ~800 km s^-1 from the galaxy center (in projection). ESO 481-G017 is found to have a 120 kpc HI disk with a mass of 1.2x10^10 Msun and UV GALEX images reveal spiral arms extending into the gaseous disk. Two dwarf galaxies with HI masses close to 10^8 Msun are detected at distances of ~200 kpc from ESO 481-G017 and a HI cloud with a mass of 6x10^7 Msun is found near the position and velocity of the remote HII region. The HII region is somewhat offset from the HI cloud spatially and there is no link to ESO 481-G017 or the dwarf galaxies. We consider several scenarios for the origin of the cloud and HII region and find the most likely is a dwarf galaxy that is undergoing ram pressure stripping. The HI mass of the cloud and Halpha luminosity of the HII region (10^38.1 erg s^-1) are consistent with dwarf galaxy properties, and the stripping can trigger the star formation as well as push the gas away from the stars.Comment: 19 pages, 4 figures, accepted by PAS

Gas Accretion is Dominated by Warm Ionized Gas in Milky Way-Mass Galaxies at z ~ 0

We perform high-resolution hydrodynamic simulations of a Milky Way-mass galaxy in a fully cosmological setting using the adaptive mesh refinement code, Enzo, and study the kinematics of gas in the simulated galactic halo. We find that the gas inflow occurs mostly along filamentary structures in the halo. The warm-hot (10^5 K 10^6 K) ionized gases are found to dominate the overall mass accretion in the system (with dM/dt = 3-5 M_solar/yr) over a large range of distances, extending from the virial radius to the vicinity of the disk. Most of the inflowing gas (by mass) does not cool, and the small fraction that manages to cool does so primarily close to the galaxy (R <~ 20 kpc), perhaps comprising the neutral gas that may be detectable as, e.g., high-velocity clouds. The neutral clouds are embedded within larger, accreting filamentary flows, and represent only a small fraction of the total mass inflow rate. The inflowing gas has relatively low metallicity (Z/Z_solar < 0.2). The outer layers of the filamentary inflows are heated due to compression as they approach the disk. In addition to the inflow, we find high-velocity, metal-enriched outflows of hot gas driven by supernova feedback. Our results are consistent with observations of halo gas at low z.Comment: 10 pages including 5 figures, submitted to Ap

Religious and Spiritual Diversity Training in Clinical Psychology Doctoral Programs: Do Explicitly Christian Programs Differ from Other Programs?

The American Psychological Association (APA) accredits several explicitly Christian doctoral programs in clinical psychology. To what extent do these programs offer training in religious and spiritual diversity that students may nor receive at orher APA-accredited programs? A total of 353 students from 5 explicitly Christian programs were surveyed using the same questionnaire used in a more general national sample of APA-accredited doctoral programs a year previously. Students in explicitly Christian programs reported receiving more training in religious and spiritual diversity and more training in advanced competencies regarding religious and spiritual issues in professional work d1an students in the general sample of AP A-accredited programs. At the same rime, students in explicitly Christian programs reported receiving less training in ethnic/ racial and socioeconomic diversity than students in other programs. Diversity training implications are considered

Isolated OB Associations in Stripped HI Gas Clouds

HST ACS/HRC images in UV (F250W), V (F555W), and I (F814W) resolve three isolated OB associations that lie up to 30 kpc from the stellar disk of the S0 galaxy NGC 1533. Previous narrow-band Halpha imaging and optical spectroscopy showed these objects as unresolved intergalactic HII regions having Halpha luminosities consistent with single early-type O stars. These young stars lie in stripped HI gas with column densities ranging from 1.5 - 2.5 * 10^20 cm^-2 and velocity dispersions near 30 km s^-1. Using the HST broadband colors and magnitudes along with previously-determined Halpha luminosities, we place limits on the masses and ages of each association, considering the importance of stochastic effects for faint (M_V >-8) stellar populations. The upper limits to their stellar masses range from 600 M_sun to 7000 M_sun, and ages range from 2 - 6 Myrs. This analysis includes an updated calculation of the conversion factor between the ionizing luminosity and the total number of main sequence O stars contained within an HII region. The photometric properties and sizes of the isolated associations and other objects in the HRC fields are consistent with those of Galactic stellar associations, open clusters and/or single O and B stars. We interpret the age-size sequence of associations and clustered field objects as an indication that these isolated associations are most likely rapidly dispersing. Furthermore, we consider the possibility that these isolated associations represent the first generation of stars in the HI ring surrounding NGC 1533. This work suggests star formation in the unique environment of a galaxy's outermost gaseous regions proceeds similarly to that within the Galactic disk and that star formation in tidal debris may be responsible for building up a younger halo component.Comment: 21 pages, 9 figures, 6 tables; accepted for publication in Ap

Outlying HII Regions in HI-Selected Galaxies

We present results from the first systematic search for outlying HII regions, as part of a sample of 96 emission-line point sources (referred to as ELdots - emission-line dots) derived from the NOAO Survey for Ionization in Neutral Gas Galaxies (SINGG). Our automated ELdot-finder searches SINGG narrow-band and continuum images for high equivalent width point sources outside the optical radius of the target galaxy (> 2 X r25 in the R-band). Follow-up longslit spectroscopy and deep GALEX images (exposure time > 1000 s) distinguish outlying HII regions from background galaxies whose strong emission lines ([OIII], Hbeta or [OII]) have been redshifted into the SINGG bandpass. We find that these deep GALEX images can serve as a substitute for spectroscopic follow-up because outlying HII regions separate cleanly from background galaxies in color-color space. We identify seven SINGG systems with outlying massive star formation that span a large range in Halpha luminosities corresponding to a few O stars in the most nearby cases, and unresolved dwarf satellite companion galaxies in the most distant cases. Six of these seven systems feature galaxies with nearby companions or interacting galaxies. Furthermore, our results indicate that some outlying HII regions are linked to the extended-UV disks discovered by GALEX, representing emission from the most massive O stars among a more abundant population of lower mass (or older) star clusters. The overall frequency of outlying HII regions in this sample of gas-rich galaxies is 8 - 11% when we correct for background emission-line galaxy contamination (~75% of ELdots).Comment: 20 pages, 14 Figures, Accepted by A

Intergalactic HII Regions Discovered in SINGG

A number of very small isolated HII regions have been discovered at projected distances up to 30 kpc from their nearest galaxy. These HII regions appear as tiny emission line objects in narrow band images obtained by the NOAO Survey for Ionization in Neutral Gas Galaxies (SINGG). We present spectroscopic confirmation of four isolated HII regions in two systems, both systems have tidal HI features. The results are consistent with stars forming in interactive debris due to cloud-cloud collisions. The H-alpha luminosities of the isolated HII regions are equivalent to the ionizing flux of only a few O stars each. They are most likely ionized by stars formed in situ, and represent atypical star formation in the low density environment of the outer parts of galaxies. A small but finite intergalactic star formation rate will enrich and ionize the surrounding medium. In one system, NGC 1533, we calculate a star formation rate of 1.5e-3 msun/yr, resulting in a metal enrichment of ~1e-3 solar for the continuous formation of stars. Such systems may have been more common in the past and a similar enrichment level is measured for the `metallicity floor' in damped Lyman-alpha absorption systems.Comment: accepted for publication in the Astronomical Journal, 19 pages, including 5 figures, some low resolution. Paper with high resolution images can be downloaded from http://astro.ph.unimelb.edu.au/~eryan/publications/eldots.ps.g

The Survey for Ionization in Neutral Gas Galaxies- II. The Star Formation Rate Density of the Local Universe

We derive observed Halpha and R band luminosity densities of an HI-selected sample of nearby galaxies using the SINGG sample to be l_Halpha' = (9.4 +/- 1.8)e38 h_70 erg s^-1 Mpc^-3 for Halpha and l_R' = (4.4 +/- 0.7)e37 h_70 erg s^-1 A^-1 Mpc^-3 in the R band. This R band luminosity density is approximately 70% of that found by the Sloan Digital Sky Survey. This leads to a local star formation rate density of log(SFRD) = -1.80 +0.13/-0.07(random) +/- 0.03(systematic) + log(h_70) after applying a mean internal extinction correction of 0.82 magnitudes. The gas cycling time of this sample is found to be t_gas = 7.5 +1.3/-2.1 Gyr, and the volume-averaged equivalent width of the SINGG galaxies is EW(Halpha) = 28.8 +7.2/-4.7 A (21.2 +4.2/-3.5 A without internal dust correction). As with similar surveys, these results imply that SFRD(z) decreases drastically from z ~ 1.5 to the present. A comparison of the dynamical masses of the SINGG galaxies evaluated at their optical limits with their stellar and HI masses shows significant evidence of downsizing: the most massive galaxies have a larger fraction of their mass locked up in stars compared with HI, while the opposite is true for less massive galaxies. We show that the application of the Kennicutt star formation law to a galaxy having the median orbital time at the optical limit of this sample results in a star formation rate decay with cosmic time similar to that given by the SFRD(z) evolution. This implies that the SFRD(z) evolution is primarily due to the secular evolution of galaxies, rather than interactions or mergers. This is consistent with the morphologies predominantly seen in the SINGG sample.Comment: 15 pages, 5 figures, ApJ in press. Data available at http://sungg.pha.jhu.edu/PubData/ Corrected: Minor typos and formatting issues fixe

The Survey for Ionization in Neutral Gas Galaxies: I. Description and Initial Results

We introduce the Survey for Ionization in Neutral Gas Galaxies (SINGG), a census of star formation in HI-selected galaxies. The survey consists of H-alpha and R-band imaging of a sample of 468 galaxies selected from the HI Parkes All Sky Survey (HIPASS). The sample spans three decades in HI mass and is free of many of the biases that affect other star forming galaxy samples. We present the criteria for sample selection, list the entire sample, discuss our observational techniques, and describe the data reduction and calibration methods. This paper focuses on 93 SINGG targets whose observations have been fully reduced and analyzed to date. The majority of these show a single Emission Line Galaxy (ELG). We see multiple ELGs in 13 fields, with up to four ELGs in a single field. All of the targets in this sample are detected in H-alpha indicating that dormant (non-star forming) galaxies with M(HI) > ~3e7 M_sun are very rare. A database of the measured global properties of the ELGs is presented. The ELG sample spans four orders of magnitude in luminosity (H-alpha and R-band), and H-alpha surface brightness, nearly three orders of magnitude in R surface brightness and nearly two orders of magnitude in H-alpha equivalent width (EW). The surface brightness distribution of our sample is broader than that of the Sloan Digital Sky Survey spectroscopic sample, the (EW) distribution is broader than prism-selected samples, and the morphologies found include all common types of star forming galaxies (e.g. irregular, spiral, blue compact dwarf, starbursts, merging and colliding systems, and even residual star formation in S0 and Sa spirals). (abridged)Comment: 28 pages, ApJS, in press. Full resolution version with all panels of Fig. 8 available at http://sungg.pha.jhu.edu/publications.html . On line data available at http://sungg.pha.jhu.edu/PubData/ . Author list corrected. Wrong value for f_ap used in eq. 7 now corrected; typos corrected, non-used references replaced, others update