44 research outputs found
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The E-Quality Service Model: Collaboration between the Reference and Circulation departments as a means to improve the library experience for distance education patrons in an academic library
This presentation discusses collaboration between the reference and circulation departments as a means to improve the library experience for distance education patrons in an academic library. The two authors give perspectives from the University of North Texas (UNT) Libraries
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Simple Ways to Add Active Learning to Your Library Instruction
This paper discusses library instruction. Assessments are recommended to determine the effectiveness of student learning. This paper also discusses a project by the UNT Libraries' in which they developed software to assess library instruction, called Library Instruction Software for Assessment (LISA) and the outcome of that study
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Teamwork, Communication, and Critical Thinking: Librarian/University Collaboration for Student E-Portfolios
Poster presented at the 2018 American Library Association Annual Conference. This poster describes the collaborations involved in promoting student e-portfolios
The Physical Origins of The Morphology-Density Relation: Evidence for Gas Stripping from the SDSS
We provide a physical interpretation and explanation of the
morphology-density relation for galaxies, drawing on stellar masses, star
formation rates, axis ratios and group halo masses from the Sloan Digital Sky
Survey. We first re-cast the classical morphology-density relation in more
quantitative terms, using low star formation rate (quiescence) as a proxy for
early-type morphology and dark matter halo mass from a group catalog as a proxy
for environmental density: for galaxies of a given stellar mass the quiescent
fraction is found to increase with increasing dark matter halo mass. Our novel
result is that - at a given stellar mass - quiescent galaxies are significantly
flatter in dense environments, implying a higher fraction of disk galaxies.
Supposing that the denser environments differ simply by a higher incidence of
quiescent disk galaxies that are structurally similar to star-forming disk
galaxies of similar mass, explains simultaneously and quantitatively these
quiescence -nvironment and shape-environment relations. Our findings add
considerable weight to the slow removal of gas as the main physical driver of
the morphology-density relation, at the expense of other explanations.Comment: published in ApJ: http://adsabs.harvard.edu/abs/2010ApJ...714.1779
Less than 10 percent of star formation in z=0.6 massive galaxies is triggered by major interactions
Both observations and simulations show that major tidal interactions or
mergers between gas-rich galaxies can lead to intense bursts of starformation.
Yet, the average enhancement in star formation rate (SFR) in major mergers and
the contribution of such events to the cosmic SFR are not well estimated. Here
we use photometric redshifts, stellar masses and UV SFRs from COMBO-17, 24
micron SFRs from Spitzer and morphologies from two deep HST cosmological survey
fields (ECDFS/GEMS and A901/STAGES) to study the enhancement in SFR as a
function of projected galaxy separation. We apply two-point projected
correlation function techniques, which we augment with morphologically-selected
very close pairs (separation <2 arcsec) and merger remnants from the HST
imaging. Our analysis confirms that the most intensely star-forming systems are
indeed interacting or merging. Yet, for massive (M* > 10^10 Msun) star-forming
galaxies at 0.4<z<0.8, we find that the SFRs of galaxies undergoing a major
interaction (mass ratios <1:4 and separations < 40 kpc) are only 1.80 +/- 0.30
times higher than the SFRs of non-interacting galaxies when averaged over all
interactions and all stages of the interaction, in good agreement with other
observational works.
We demonstrate that these results imply that <10% of star formation at 0.4 <
z < 0.8 is triggered directly by major mergers and interactions; these events
are not important factors in the build-up of stellar mass since z=1.Comment: Submitted to ApJ. 41 pages, 11 figure
The Morphology of Galaxies in the Baryon Oscillation Spectroscopic Survey
We study the morphology of luminous and massive galaxies at 0.3<z<0.7
targeted in the Baryon Oscillation Spectroscopic Survey (BOSS) using publicly
available Hubble Space Telescope imaging from COSMOS. Our sample (240 objects)
provides a unique opportunity to check the visual morphology of these galaxies
which were targeted based solely on stellar population modelling. We find that
the majority (74+/-6%) possess an early-type morphology (elliptical or S0),
while the remainder have a late-type morphology. This is as expected from the
goals of the BOSS target selection which aimed to predominantly select slowly
evolving galaxies, for use as cosmological probes, while still obtaining a fair
fraction of actively star forming galaxies for galaxy evolution studies. We
show that a colour cut of (g-i)>2.35 selects a sub-sample of BOSS galaxies with
90% early-type morphology - more comparable to the earlier Luminous Red Galaxy
(LRG) samples of SDSS-I/II. The remaining 10% of galaxies above this cut have a
late-type morphology and may be analogous to the "passive spirals" found at
lower redshift. We find that 23+/-4% of the early-type galaxies are unresolved
multiple systems in the SDSS imaging. We estimate that at least 50% of these
are real associations (not projection effects) and may represent a significant
"dry merger" fraction. We study the SDSS pipeline sizes of BOSS galaxies which
we find to be systematically larger (by 40%) than those measured from HST
images, and provide a statistical correction for the difference. These details
of the BOSS galaxies will help users of the data fine-tune their selection
criteria, dependent on their science applications. For example, the main goal
of BOSS is to measure the cosmic distance scale and expansion rate of the
Universe to percent-level precision - a point where systematic effects due to
the details of target selection may become important.Comment: 18 pages, 11 figures; v2 as accepted by MNRA
The green valley is a red herring : Galaxy Zoo reveals two evolutionary pathways towards quenching of star formation in early-and late-type galaxies
This is a pre-copyedited, author-produced PDF of an article accepted for publication in Monthly Notices of the Royal Astronomical Society following peer review. The version of record [Kevin Schawinski, et al, 'The green valley is a red herring: Galaxy Zoo reveals two evolutionary pathways towards quenching of star formation in early- and late-type galaxies' MNRAS, Vol. 440(1): 889-907, May 2014] is available online at: https://doi.org/10.1093/mnras/stu327.We use SDSS+GALEX+Galaxy Zoo data to study the quenching of star formation in lowredshift galaxies. We show that the green valley between the blue cloud of star-forming galaxies and the red sequence of quiescent galaxies in the colour-mass diagram is not a single transitional state through which most blue galaxies evolve into red galaxies. Rather, an analysis that takes morphology into account makes clear that only a small population of blue early-type galaxies move rapidly across the green valley after the morphologies are transformed from disc to spheroid and star formation is quenched rapidly. In contrast, the majority of blue star-forming galaxies have significant discs, and they retain their late-type morphologies as their star formation rates decline very slowly. We summarize a range of observations that lead to these conclusions, including UV-optical colours and halo masses, which both show a striking dependence on morphological type. We interpret these results in terms of the evolution of cosmic gas supply and gas reservoirs. We conclude that late-type galaxies are consistent with a scenario where the cosmic supply of gas is shut off, perhaps at a critical halo mass, followed by a slow exhaustion of the remaining gas over several Gyr, driven by secular and/or environmental processes. In contrast, early-type galaxies require a scenario where the gas supply and gas reservoir are destroyed virtually instantaneously, with rapid quenching accompanied by a morphological transformation from disc to spheroid. This gas reservoir destruction could be the consequence of a major merger, which in most cases transforms galaxies from disc to elliptical morphology, and mergers could play a role in inducing black hole accretion and possibly active galactic nuclei feedback.Peer reviewe
Cytokine Gene Polymorphisms and Length of Gestation
To estimate whether there is an association between length of gestation and gene polymorphisms that effect transcription of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), or interleukin-1ÎČ (IL-1ÎČ)
Denkwerkstatt "Ressourcenknappheit"- Handlungs- und Aktionsfelder II
Vorwort:
Non-Profit Manager*innen von heute sind Generalist*innen, die sich initiativ und eigenverantwortlich mit den Herausforderungen unserer Zeit auseinandersetzen und im besten Falle geeignete Lösungen dafĂŒr finden und diese auch richtig kommunizieren können. Aus diesem Grunde wird genau diese FĂ€higkeit bei Studierenden aus den MasterstudiengĂ€ngen Management in Nonprofit-Organisationen und Soziale Arbeit der Hochschule OsnabrĂŒck gefördert.
Im Rahmen des Moduls Handlungsfelder II entwickelten rund 30 Studierende im Wintersemester 2020/2021 in einer Denkwerkstatt ihre eigenen Lösungen in Bezug auf Forschung, Produkte / Dienstleistungen und Kommunikation. Die Studierenden wÀhlten in einem partizipativen Prozess ihre eigenen Schwerpunktthemen aus und arbeiteten dann ein Semester lang an den Inhalten.
Begleitet wurden sie durch ein Teamteaching von Prof. Dr. Gesa Birnkraut und Marlene EimterbĂ€umer, die Modelle, Methoden und Coaching zur UnterstĂŒtzung anboten. Die Modelle und Methoden finden sich in den BeitrĂ€gen der Studierenden wieder (unter anderem das socio-ecological model, der Business Model Canvas, der story telling canvas, das design thinking).
Am Ende des Semesters stand eine PrĂ€sentation vor den Kommiliton*innen und den Lehrenden, aber auch vor externen GĂ€sten, die aus unterschiedlichen Expertisegebieten kamen und dementsprechend Feedback gaben. Das Modul selbst wurde von der Hochschule im Rahmen der Innovativen Lehre an der FakultĂ€t Wirtschafts- und Sozialwissenschaften gefördert. FĂŒr die Studierenden stellte das Modul durchaus eine groĂe Herausforderung dar, denn in der Denkwerkstatt musste unter hoher KomplexitĂ€t stark prozessbezogen gearbeitet werden im Gegensatz zu der sonstigen hohen Ergebnisorientierung.
Die durchweg sehr guten Ergebnisse zeigen, dass der Einsatz und das Aushalten der Unsicherheit sich gelohnt haben. Aufgeteilt ist das vorliegende Buch in die zwei Schwerpunktthemen Ressourcenknappheit / Wirtschaft und Wasserknappheit. In diesen beiden Schwerpunktthemen finden Sie jeweils einen Beitrag von den Forscher*innen, den Lösungsfinder*innen und den Kommunikator*innen