IRAS 16293-2422: Evidence for Infall onto a Counter-Rotating Protostellar Accretion Disk

We report high spatial resolution VLA observations of the low-mass star-forming region IRAS 16293-2422 using four molecular probes: ethyl cyanide (CH$_3$CH$_2$CN), methyl formate (CH$_3$OCHO), formic acid (HCOOH), and the ground vibrational state of silicon monoxide (SiO). Ethyl cyanide emiss ion has a spatial scale of $\sim20''$ and encompasses binary cores A and B as determined by continuum emission peaks. Surrounded by formic acid emission, methyl formate emission has a spatial scale of $\sim6''$and is confined to core B. SiO emission shows two velocity components with spatial scales less than 2$''$ that map $\sim2''$ northeast of the A and B symmetry axis. The redshifted SiO is $\sim2''$ northwest of blueshifted SiO along a position angle of $\sim135^o$ which is approximately parallel to the A and B symmetry axis. We interpret the spatial position offset in red and blueshifted SiO emission as due to rotation of a protostellar accretion disk and we derive $\sim$1.4 M$_{\odot}$ interior to the SiO emission. In the same vicinity, Mundy et al. (1986) also concluded rotation of a nearly edge-on disk from OVRO observations of much stronger and ubiquitous $^{13}$CO emission but the direction of rotation is opposite to the SiO emission findings. Taken together, SiO and $^{13}$CO data suggest evidence for a counter-rotating disk. Moreover, archival BIMA array $^{12}$CO data show an inverse P Cygni profile with the strongest absorption in close proximity to the SiO emission, indicating unambiguous material infall toward the counter-rotating protostellar disk at a new source location within the IRAS 16293-2422 complex. The details of these observations and our interpretations are discussed.Comment: 18 pages, 5 figures, accepted for publication in the Astrophysical Journa

Summary of Workshop to Review an OMB Report on Regulatory Risk Assessment and Management

Summary of the results of an invitational workshop conducted to peer review the 1990 OMB report, CURRENT REGULATORY ISSUES IN Risk ASSESSMENT AND Risk MANAGENMENTIN REGULATORY PROGRAM OF THE UNITED STATES GOVERNMENT, APRIL 1, 1990 - MARCH 31, 1991

Protective Effects of Calcium Against Chronic Waterborne Cadmium Exposure to Juvenile Rainbow Trout

Juvenile rainbow trout (Oncorhynchus mykiss [Walbaum]) on 1% daily ration were exposed to 0 (control) or 2 μg of cadmium as Cd(NO3)2·4H2O per liter added to four different calcium (Ca) concentrations: 260 (background), 470 (low), 770 (medium), or 1200 (high) μM of Ca added as Cd(NO3)2·4H2O in synthetic soft water for 30 d. Mortality was highest (;80%) in the background 1 Cd treatment. Approximately 40% mortality was observed in the low 1 Cd exposure; mortality was 10% or less for all other treatments. No growth effects were seen for any of the exposures. Kidneys accumulated the greatest concentration of Cd during the 30 d, followed by gills and livers. Accumulation of Cd in gills, kidney, and liver decreased at higher water Ca concentrations. No differences in whole-body or plasma Ca concentrations were found. Swimming performance was impaired in the low + Cd-exposed fish. Influx of Ca2+ into whole bodies decreased as water Ca concentrations increased; influx of Ca2+ into background + Cd–treated fish was significantly reduced compared to that in control fish. Experiments that measured uptake of new Cd into gills showed that the affinity of gills for Cd (KCd-gill) and the number of binding sites for Cd decreased as water Ca concentrations increased. Acute accumulation of new Cd into gills and number of gill Cd-binding sites increased with chronic Cd exposure, whereas the affinity of gills for Cd decreased with chronic Cd exposure. Longer-term gill binding (72 h) showed reduced uptake of new Cd at higher water Ca levels and increased uptake with chronic Cd exposure. Complications were found in applying the biotic ligand model to fish that were chronically exposed to Cd because of discrepancies in the maximum number of gill Cd-binding sites among different studies

Export of invertebrate drift from fishless headwater streams

An understanding of ecological linkages between headwater systems and downstream habitats is needed to enhance management practices for aquatic conservation. I quantified and described the export of invertebrate drift from fishless headwater streams to assess its potential importance to downstream populations of coastal cutthroat trout (Oncorhynchus clarki clarki) in the lower Klamath River in northern California. From June 2015 through April 2016, I sampled invertebrate drift in six fishless headwaters in the sub-basins of Tectah, Ah Pah, and Tarup creeks. Concurrently, I collected invertebrate drift and trout diet samples from adjoining fish-bearing streams. Drift export rates were lowest in October and greatest in April, and ranged from 98 - 1331 mg dry mass stream-1 d-1. Invertebrate taxa of aquatic origin dominated drift biomass in fishless streams on all four sampling occasions; the proportion of terrestrially-derived biomass was highest in October. Estimates of daily drift flux in fish-bearing streams exceeded the delivery of drift mass from fishless streams throughout the year. Trout diet samples demonstrated tremendous variability in invertebrate biomass among individuals within seasons. However, average biomass per diet sample differed strongly among sampling occasions, and was greatest in April. Terrestrial taxa dominated the biomass of trout diets in June and October. Both drift and diet samples were taxonomically rich, but exhibited little similarity to each other. I estimated drift exports from fishless headwaters could support a maximum of 37 g dry mass stream-1 year-1 of trout, theoretically accounting for one-tenth to one-quarter of the annual production of over-yearling trout in the study streams

Control valve: Hot gas fast response

The design of a warm gas control valve is reviewed outlining the problems posed by the requirement for extremely fast response combined with a severe environment and a hot, dirty, and corrosive operating fluid

Due Process in Higher Education: A Study of Due Process in Relation to Greek Life Affairs

Fraternities have blazed headlines over the past several years due to incidents involving degrading and racist chants, private Facebook groups bragging about illicit behavior, and in several cases, allegations of sexual assault. This project serves to investigate the constitutional rights of Fraternities and Sororities during investigative and disciplinary procedures. A major concern that this project explores is whether organizations are protected under the 14th Amendment of the Constitution in university disciplinary procedures. This project provides a thorough discussion of the history of Greek organizations and their significance. It also conducts an exhaustive review of the 14th Amendment’s Due Process Clause and how it applies to universities through their established Student Code of Conduct1. This piece investigates Student Code of Conduct policies from sixteen college campuses in the Midwest to determine how sanctions are delivered to student organizations; half of the universities require student organizations to be punished in the same way as individual students. Three universities have separate policies or have clauses that determine how organizations should be punished. This project also provides an in-depth look into the growing trend of the Court system not finding the University to be responsible if they are sued as a result of an incident involving a Greek organizations.Kayla SiddellHonors DiplomaHonors CollegeCunningham Memorial Library, Terre Haute, Indiana State UniversityUndergraduateTitle from document title page. Document formatted into pages: 24

Screening for autism in preterm children : diagnostic utility of the Social Communication Questionnaire

Objective Preterm survivors are at high risk for autism spectrum disorders (ASD). The diagnostic utility of the Social Communication Questionnaire (SCQ) in screening for ASD was assessed in extremely preterm children at 11 years of age. Design All babies born at <26 weeks gestation in UK and Ireland from March through December 1995 were recruited to the EPICure Study. Of 307 survivors, 219 (71%) were assessed at 11 years. Parents of 173 children completed the SCQ to screen for autistic features and the Development and Well Being Assessment (DAWBA) psychiatric interview. A consensus diagnosis of ASD was assigned by two child psychiatrists following review of the DAWBA parental interview and corresponding DAWBA teacher questionnaire. Setting Community-based follow-up. Results Using the established SCQ cut-off (scores ≥15), 28 (16%) extremely preterm children screened positive for ASD. Eleven (6%) were assigned a diagnosis of ASD. Using this cut-off, the SCQ had 82% sensitivity and 88% specifi city for identifying ASD in this population. Using a receiver operating characteristic curve, SCQ scores ≥14 had optimal diagnostic utility (area under curve: 0.94; sensitivity: 91%; specifi city: 86%). Positive predictive value was relatively low (31%) resulting in numerous over-referrals. However, children with false positive screens had signifi cantly worse neuro-developmental, cognitive and behavioural outcomes than those with true negative screens. Conclusion The SCQ has good diagnostic utility for identifying ASD in extremely preterm children and is a useful screening tool in this population. Children with false positive screens represent a high-risk group in whom further diagnostic assessment would be benefi cial

Effects of musical collaboration on intergroup attitudes

Music is an important presence in our world, thought to be universal in human societies. The ubiquity of music has led some to postulate that it might have an important evolutionary purpose. One theory about the purpose of music is that it helps facilitate the social aspects of our existence. If this is the case, music has the potential to be a powerful tool for change. Indeed, some research has suggested that music can increase positive intergroup interactions. Thus far, the research has shown that music may produce change in intergroup attitudes when accompanied by other intergroup interactions, such as cohabitation. It has also shown promise in relation to music preference and witnessed musical interaction. However, evidence for increased positive intergroup attitudes following actual (instead of imagined, vicarious, or witnessed) musical interaction in a controlled environment is still lacking. The purpose of this study was to test this idea. One hundred eighty-two undergraduate psychology students were recruited to complete musical tasks in collaboration, a non-musical task in collaboration, or a musical task alone (isolation). I hypothesized that (1) relative to intergroup non-musical collaboration, intergroup musical collaboration will lead to an increase in positive intergroup attitudes; and (2) musical isolation will lead to minimal or no increase in positive intergroup attitudes. The results of this study did not support these hypotheses.Includes bibliographical reference

Non-Thermal Continuum toward SGRB2(N-LMH)

An analysis of continuum antenna temperatures observed in the Green Bank Telescope (GBT) spectrometer bandpasses is presented for observations toward SgrB2(N-LMH). Since 2004, we have identified four new prebiotic molecules toward this source by means of rotational transitions between low energy levels; concurrently, we have observed significant continuum in the GBT spectrometer bandpasses centered at 85 different frequencies in the range of 1 to 48 GHz. The continuum heavily influences the molecular spectral features since we have observed far more absorption lines than emission lines for each of these new molecular species. Hence, it is important to understand the nature, distribution, and intensity of the underlying continuum in the GBT bandpasses for the purposes of radiative transfer, i.e. the means by which reliable molecular abundances are estimated. We find that the GBT spectrometer bandpass continuum is consistent with optically-thin, non thermal (synchrotron) emission with a flux density spectral index of -0.7 and a Gaussian source size of ~143" at 1 GHz that decreases with increasing frequency as nu^(-0.52). Some support for this model is provided by high frequency Very Large Array (VLA) observations of SgrB2.Comment: Accepted for Publication in the Astrophysical Journal Letter