The Characteristics of Occupational Students in Postsecondary Education

This Brief presents a profile of the enrollment, demographic, and educational characteristics, and the educational goals, of community college students in occupational programs. It compares their features with those of community college students in academic programs and with baccalaureate students. This analysis further considers the distinct features of occupational students enrolled in certificate degree programs. The Brief stands alone as a comparative description of these students, but also provides important background material for CCRC’s companion Briefs on postsecondary occupational students, Educational Outcomes of Postsecondary Occupational Students and Who Benefits from Postsecondary Occupational Education? Findings from the 1980s and 1990s

Beyond Student Right-to-Know Data: Factors That Can Explain Community College Graduation Rates

Policymakers, educators, and researchers recognize the importance of community colleges as open door institutions that provide a wide range of students with access to college. At the same time, competing demands for the state funds that would support community colleges have resulted in reduced public allocations and higher student tuition fees. Understandably, therefore, both state policymakers and parents are increasingly focused on the returns to their public or private investments in education, and the outcomes of community college attendance are now under greater scrutiny. To facilitate the evaluation of the colleges, there are now available data, through the Student Right-to-Know and Campus Security Act (1990), which amended the Higher Education Act, on every college’s graduation rate for fall semester cohorts of first-time, fulltime (FTFT) students in degree programs. This information is known as the Student Right-to-Know (SRK) data. A related public concern is how the outcomes of community college students can be improved. Therefore, attempts are now being made to clarify the way that specific students define success and to identify the college policies and practices that can promote success for all students. For some community college students, college completion, defined as earning a degree or certificate, is the appropriate measure of success. For other students, success is demonstrated by transferring to a baccalaureate institution. Still others are satisfied with completing courses that increase their knowledge or skill level in a particular area even though their educational experience is not considered successful as defined by traditional educational outcomes

The Effects of Institutional Factors on the Success of Community College Students

Community colleges are the gateway to higher education for many students who would otherwise have limited access to college, particularly those who are from low-income households or are ethnic minorities, first generation college students, or immigrants. Yet only about one-third of all community college students receives any degree or certificate even eight years after initial college enrollment. And credit accumulation and completion rates are even lower for minority and low-income students. Meanwhile, community college student outcomes, as measures of college effectiveness, are of increasing concern for institutional accountability. The Bush administration and many legislators in Congress would like to hold postsecondary institutions to higher standards of accountability, just as they have done with elementary and secondary schools. Institutional reporting requirements to the Department of Education now include data for graduation rates overall and broken out by gender and race/ethnicity. More than half of all states take into account the performance of public colleges when determining higher education appropriations

New Extinction and Mass Estimates from Optical Photometry of the Very Low Mass Brown Dwarf Companion CT Chamaeleontis B with the Magellan AO System

We used the Magellan adaptive optics (MagAO) system and its VisAO CCD camera to image the young low mass brown dwarf companion CT Chamaeleontis B for the first time at visible wavelengths. We detect it at r', i', z', and Ys. With our new photometry and Teff~2500 K derived from the shape its K-band spectrum, we find that CT Cha B has Av = 3.4+/-1.1 mag, and a mass of 14-24 Mj according to the DUSTY evolutionary tracks and its 1-5 Myr age. The overluminosity of our r' detection indicates that the companion has significant Halpha emission and a mass accretion rate ~6*10^-10 Msun/yr, similar to some substellar companions. Proper motion analysis shows that another point source within 2" of CT Cha A is not physical. This paper demonstrates how visible wavelength AO photometry (r', i', z', Ys) allows for a better estimate of extinction, luminosity, and mass accretion rate of young substellar companions.Comment: Accepted for publication in ApJ; 6 figure

New Extinction and Mass Estimates of the Low-mass Companion 1RXS 1609 B with the Magellan AO System: Evidence of an Inclined Dust Disk

We used the Magellan adaptive optics system to image the 11 Myr substellar companion 1RXS 1609 B at the bluest wavelengths to date (z' and Ys). Comparison with synthetic spectra yields a higher temperature than previous studies of $T_\mathrm{eff}=2000\pm100\mathrm{K}$ and significant dust extinction of $A_V=4.5^{+0.5}_{-0.7}$ mag. Mass estimates based on the DUSTY tracks gives 0.012-0.015 Msun, making the companion likely a low-mass brown dwarf surrounded by a dusty disk. Our study suggests that 1RXS 1609 B is one of the 25% of Upper Scorpius low-mass members harboring disks, and it may have formed like a star and not a planet out at 320 AU.Comment: 5 pages, 4 figures; accepted to ApJ

Clinical outcomes in high-hypoglycaemia-risk patients with type 2 diabetes switching to insulin glargine 300 U/mL versus a first-generation basal insulin analogue in the United States: Results from the DELIVER High Risk real-world study

Aims: To compare 12-month clinical effectiveness of insulin glargine 300 units/mL (Gla-300) versus first-generation basal insulin analogues (BIAs) (insulin glargine 100 units/mL [Gla-100] or insulin detemir [IDet]) in patients with type 2 diabetes (T2D) who were at high risk of hypoglycaemia and switched from one BIA to a different one (Gla-300 or Gla-100/IDet) in a real-world setting. // Methods: DELIVER High Risk was a retrospective observational cohort study of 2550 patients with T2D who switched BIA to Gla-300 (Gla-300 switchers) and were propensity score-matched (1:1) to patients who switched to Gla-100 or IDet (Gla-100/IDet switchers). Outcomes were change in glycated haemoglobin A1c (HbA1c), attainment of HbA1c goals (<7% and <8%), and incidence and event rates of hypoglycaemia (all-hypoglycaemia and hypoglycaemia associated with an inpatient/emergency department [ED] contact). // Results: HbA1c reductions were similar following switching to Gla-300 or Gla-100/IDet (−0.51% vs. −0.53%; p = .67), and patients showed similar attainment of HbA1c goals. Patients in both cohorts had comparable all-hypoglycaemia incidence and event rates. However, the Gla-300 switcher cohort had a significantly lower risk of inpatient/ED-associated hypoglycaemia (adjusted odds ratio: 0.73, 95% confidence interval: 0.60–0.89; p = .002) and experienced significantly fewer inpatient/ED-associated hypoglycaemic events (0.21 vs. 0.33 events per patient per year; p < .001). // Conclusion: In patients with T2D at high risk of hypoglycaemia, switching to Gla-300 or Gla-100/IDet achieved similar HbA1c reductions and glycaemic goal attainment, but Gla-300 switchers had a significantly lower risk of hypoglycaemia associated with an inpatient/ED contact during 12 months after switching

New Spatially Resolved Observations of the T Cha Transition Disk and Constraints on the Previously Claimed Substellar Companion

We present multi-epoch non-redundant masking observations of the T Cha transition disk, taken at the VLT and Magellan in H, Ks, and L' bands. T Cha is one of a small number of transition disks that host companion candidates discovered by high-resolution imaging techniques, with a putative companion at a position angle of 78 degrees, separation of 62 mas, and contrast at L' of 5.1 mag. We find comparable binary parameters in our re-reduction of the initial detection images, and similar parameters in the 2011 L', 2013 NaCo L', and 2013 NaCo Ks data sets. We find a close-in companion signal in the 2012 NaCo L' dataset that cannot be explained by orbital motion, and a non-detection in the 2013 MagAO/Clio2 L' data. However, Monte-carlo simulations show that the best fits to the 2012 NaCo and 2013 MagAO/Clio2 followup data may be consistent with noise. There is also a significant probability of false non-detections in both of these data sets. We discuss physical scenarios that could cause the best fits, and argue that previous companion and scattering explanations are inconsistent with the results of the much larger dataset presented here.Comment: 25 pages, 22 figures, accepted for publication in Ap

Directly Imaged L-T Transition Exoplanets in the Mid-Infrared

Gas-giant planets emit a large fraction of their light in the mid-infrared ($\gtrsim$3$\mu$m), where photometry and spectroscopy are critical to our understanding of the bulk properties of extrasolar planets. Of particular importance are the L and M-band atmospheric windows (3-5$\mu$m), which are the longest wavelengths currently accessible to ground-based, high-contrast imagers. We present binocular LBT AO images of the HR 8799 planetary system in six narrow-band filters from 3-4$\mu$m, and a Magellan AO image of the 2M1207 planetary system in a broader 3.3$\mu$m band. These systems encompass the five known exoplanets with luminosities consistent with L$\rightarrow$T transition brown dwarfs. Our results show that the exoplanets are brighter and have shallower spectral slopes than equivalent temperature brown dwarfs in a wavelength range that contains the methane fundamental absorption feature (spanned by the narrowband filters and encompassed by the broader 3.3$\mu$m filter). For 2M1207 b, we find that thick clouds and non-equilibrium chemistry caused by vertical mixing can explain the object's appearance. For the HR 8799 planets, we present new models that suggest the atmospheres must have patchy clouds, along with non-equilibrium chemistry. Together, the presence of a heterogeneous surface and vertical mixing presents a picture of dynamic planetary atmospheres in which both horizontal and vertical motions influence the chemical and condensate profiles.Comment: Accepted to Ap

A Study of the Diverse T Dwarf Population Revealed by WISE

We report the discovery of 87 new T dwarfs uncovered with the Wide-field Infrared Survey Explorer (WISE) and three brown dwarfs with extremely red near-infrared colors that exhibit characteristics of both L and T dwarfs. Two of the new T dwarfs are likely binaries with L7+/-1 primaries and mid-type T secondaries. In addition, our follow-up program has confirmed 10 previously identified T dwarfs and four photometrically-selected L and T dwarf candidates in the literature. This sample, along with the previous WISE discoveries, triples the number of known brown dwarfs with spectral types later than T5. Using the WISE All-Sky Source Catalog we present updated color-color and color-type diagrams for all the WISE-discovered T and Y dwarfs. Near-infrared spectra of the new discoveries are presented, along with spectral classifications. To accommodate later T dwarfs we have modified the integrated flux method of determining spectral indices to instead use the median flux. Furthermore, a newly defined J-narrow index differentiates the early-type Y dwarfs from late-type T dwarfs based on the J-band continuum slope. The K/J indices for this expanded sample show that 32% of late-type T dwarfs have suppressed K-band flux and are blue relative to the spectral standards, while only 11% are redder than the standards. Comparison of the Y/J and K/J index to models suggests diverse atmospheric conditions and supports the possible re-emergence of clouds after the L/T transition. We also discuss peculiar brown dwarfs and candidates that were found not to be substellar, including two Young Stellar Objects and two Active Galactic Nuclei. The coolest WISE-discovered brown dwarfs are the closest of their type and will remain the only sample of their kind for many years to come.Comment: Accepted to ApJS on 15 January 2013; 99 pages in preprint format, 30 figures, 12 table

Investigation of the Impact of Increased Dietary Insoluble Fiber through the Feeding of Distillers Dried Grains with Solubles (DDGS) on the Incidence and Severity of Brachyspira-Associated Colitis in Pigs

Diet has been implicated as a major factor impacting clinical disease expression of swine dysentery and Brachyspira hyodysenteriae colonization. However, the impact of diet on novel pathogenic strongly beta-hemolytic Brachyspira spp. including “B. hampsonii” has yet to be investigated. In recent years, distillers dried grains with solubles (DDGS), a source of insoluble dietary fiber, has been increasingly included in diets of swine. A randomized complete block experiment was used to examine the effect of increased dietary fiber through the feeding of DDGS on the incidence of Brachyspira-associated colitis in pigs. One hundred 4-week-old pigs were divided into five groups based upon inocula (negative control, Brachyspira intermedia,Brachyspira pilosicoli, B. hyodysenteriae or “B. hampsonii”) and fed one of two diets containing no (diet 1) or 30% (diet 2) DDGS. The average days to first positive culture and days post inoculation to the onset of clinical dysentery in the B. hyodysenteriae groups was significantly shorter for diet 2 when compared to diet 1 (P = 0.04 and P = 0.0009, respectively). A similar difference in the average days to first positive culture and days post inoculation to the onset of clinical dysentery was found when comparing the “B. hampsonii” groups. In this study, pigs receiving 30% DDGS shed on average one day prior to and developed swine dysentery nearly twice as fast as pigs receiving 0% DDGS. Accordingly, these data suggest a reduction in insoluble fiber through reducing or eliminating DDGS in swine rations should be considered an integral part of any effective disease elimination strategy for swine dysentery