Eph receptors and ephrins in the developing chick cerebellum: relationship to sagittal patterning and granule cell migration

Spatiotemporal expression patterns of six members of the Eph gene family (EphA4, EphA3, EphB2, ephrin-B1, ephrin-A2, and ephrin-A5) were characterized immunocytochemically at various stages of chick cerebellar development. EphA4 expression is observed in the cerebellar anlage as early as embryonic day 5 (E5) and continues in the posthatch cerebellum. During the early period of cerebellar development (E3-E8), complementarity is observed between EphA4 and ephrin-A5 expression within the cerebellar-isthmal region. By E8, differential expression of EphA4 in parasagittal Purkinje cell bands is evident, and the expression remains banded in the posthatch cerebellum. Banded expression of the ephrin-A5 ligand complements EphA4 expression during the middle period (E9-E15). During this period, ephrin-A2 and EphA3 are coexpressed in a banded pattern and with variable correlation to EphA4. Variability in the banding expression is observed for EphA4, EphA3, ephrin-A5, and ephrin-A2 across different lobes, and graded complementarity in the expression pattern of EphA3 and ephrin-A5 is observed in the external granular layer between the posterior and anterior lobes. Analysis of Purkinje cell birth date in correlation with Eph-ephrin expression during the middle period reveals that early-born cells express EphA4, whereas late-born cells express ephrin-A5. Finally, EphA4 expression domains are respected by migrating granule cell ribbons, which express both ephrin-B1 and EphB2. These expression patterns suggest multiple roles for the Eph-ephrin system in cerebellar development, including demarcation/enforcement of boundaries of the cerebellar anlage, formation/maintenance of Purkinje cell compartments, and restriction of the early phase of granule cell migration to ribbons

The Ursinus Weekly, October 17, 1949

Millers contribute two chapters to volume in honor of Blakeslee • Bears seek victory over Garnet eleven in traditional fray • Soccer team drops season opener 4-0 to Castle Pointers • Booters select Peterson; Frick leads coed squad • Dickinson runs wild in easy 35-0 triumph • Curtis tops league in campus football; Ping pong to start • Gurzynski discloses cross-country slate • Popular pair views life south of the Rio Grande • Verve and style of \u2751ers maintain famed tradition of Glenwood quartet • Freshmen elect George Ott president • Frosh cuties massacre burlesque • Students hold rites for departed spirit • Actors\u27 club slates Shaw\u27s Pygmalion • Seniors name date for annual dance • Speaker prescribes change in policies for U.S. with Asia • Penn prexy will address Founders\u27 Day audience • Observatory proves valuable addition to science building • Y cabinet schedules Green Lane retreat for this week-end • Chairman explains current regulations to campus leaders • Ruby editors announce selection of staff heads for \u2750 edition • Literary publication adds five editors to masthead • Sororities prepare for rushing; Sophs to receive bids Fridayhttps://digitalcommons.ursinus.edu/weekly/1573/thumbnail.jp

ALMA observations of atomic carbon in z~4 dusty star-forming galaxies

We present ALMA [CI]($1-0$) (rest frequency 492 GHz) observations for a sample of 13 strongly-lensed dusty star-forming galaxies originally discovered at 1.4mm in a blank-field survey by the South Pole Telescope. We compare these new data with available [CI] observations from the literature, allowing a study of the ISM properties of $\sim 30$ extreme dusty star-forming galaxies spanning a redshift range $2 < z < 5$. Using the [CI] line as a tracer of the molecular ISM, we find a mean molecular gas mass for SPT-DSFGs of $6.6 \times 10^{10}$ M$_{\odot}$. This is in tension with gas masses derived via low-$J$ $^{12}$CO and dust masses; bringing the estimates into accordance requires either (a) an elevated CO-to-H$_2$ conversion factor for our sample of $\alpha_{\rm CO} \sim 2.5$ and a gas-to-dust ratio $\sim200$, or (b) an high carbon abundance $X_{\rm CI} \sim 7\times10^{-5}$. Using observations of a range of additional atomic and molecular lines (including [CI], [CII], and multiple transitions of CO), we use a modern Photodissociation Region code (3D-PDR) to assess the physical conditions (including the density, UV radiation field strength, and gas temperature) within the ISM of the DSFGs in our sample. We find that the ISM within our DSFGs is characterised by dense gas permeated by strong UV fields. We note that previous efforts to characterise PDR regions in DSFGs may have significantly underestimated the density of the ISM. Combined, our analysis suggests that the ISM of extreme dusty starbursts at high redshift consists of dense, carbon-rich gas not directly comparable to the ISM of starbursts in the local Universe.Comment: 21 pages, 12 figures. Accepted for publication in MNRA

The Ursinus Weekly, January 16, 1950

Poet Davison to appear at third Ursinus forum • Thirty-one make up semester grad list, largest at Ursinus • Coeds plan field day with Lorelei at hand • Y students journey for week-end work in negro slum area • Dr. High discusses facts of allergies for pre-med group • Campus agent plans Chesterfield series • Gals! Write pageant for fame, fortune, and fifteen dollars • WSGA names group to revise customs • Photographer films So much to be done • Student leaders complete schedule for second term • Myk enjoys life here; Admires labs, libraries • Frosh face finals • Bruin matmen garner eighth in win record • Grid lettermen pick Don Young to lead squad next season • Courtmen suffer defeat after edging Textile five • League games start in interdorm circuit • Coed athletes await opening of rosters with second termhttps://digitalcommons.ursinus.edu/weekly/1582/thumbnail.jp

The Ursinus Weekly, October 24, 1949

Five coed Greek organizations get set for annual hectic fall rushing season • Grid machine seeks win over Seahawks to avenge \u2748 loss • Poem reveals hope for beaten athletes • Pep rally precedes senior class dance • Soccer team drops second contest 2-0 at New Brunswick • Garnet drops Bears 20-6 with quick aerial attack • Curtis keeps lead; McMillan triumphs in golfing contest • Court squad opens practice workouts for coming season • Hockey team takes season opener 4-3 against Bryn Mawr • Traveller comes to roost at Ursinus • British lecturer and author to appear at Ursinus rostrum next Tuesday night • Rusty Reed heads paint-brush squad in campus publicity • Sky becomes limit in full-dress battle of annual banquet • Editorial: Sororities and fraternities • Varsity Club selects Farina band • Initial \u2753 officers take over duties following introduction at frosh banquet • Men choose three for MSGA positions • Music clubs offer two merit awards • Hungarian to talk at vesper service • Stassen views theories shaping world cultures • Sophs offer variety in coming week-end • Allen and Aiken cop leading portrayals in December play • Fulbright act gives full financial aid for foreign study • Kitchen adds new refrigerator, other equipment during summerhttps://digitalcommons.ursinus.edu/weekly/1574/thumbnail.jp

The Ursinus Weekly, February 27, 1950

Cytologists to give material on cancer from U.S. research • Clothing drive opens today for overseas • Steere to consider Sense of Vocation for emphasis week • Coed societies map strategy in rushing season\u27s candidates • Committee requests coeds\u27 suggestions on customs matter • Week-end promises full-time enjoyment with carnival, shag • Sophs to highlight velvet mood at hop; present Art Brown • Actors to produce one-act group plays • Pre-legals prepare for ICG convention • Cerone opens drive for heart patients in talk to students • Foreign service agent tells story of escape from Asia • Ann Royer receives award for highest Chem I average • Oil burner explosion rocks equilibrium of Hobson Hall • Omwake receives committee job to make school business survey • Dr. Armstrong receives position • Rue makes railroads life project • Editorial: Benign influence • Annex-dotes • Old Weeklies reveal fads, innovations as new dorm, gate appear on scene • Ruby staff leers as night of horrors augments treasury • Horseback riders meet to plan future activities at academies • Ruby staff to stage musical; begin tryouts for cast tonight • Gravediggers ply trade on hardwood lib tables • Emily loses face on Ursinus campus as student diners turn to rules, tux • Science lib offers rare secluded nook for deep pondering • Garnet whips bears 19-11 with experienced squad • Intramural news • Penn ties bearettes; Rosemont succumbs • Wrestlers face tourney for MA championship • Bruins drop two games as losing streak grows • Tank squad sweeps victory from Penn, taking five firsts • Bruin matmen take easy 34-0 decision from Cadet squad • WAA selects coed endmen for comedy, musical showhttps://digitalcommons.ursinus.edu/weekly/1585/thumbnail.jp

The star formation rate distribution function of the local Universe

We present total infrared (IR) and ultraviolet (UV) luminosity functions derived from large representative samples of galaxies at z ~ 0, selected at IR and UV wavelengths from the Imperial IRAS Faint Source Catalogue redshift data base (IIFSCz) catalogue, and the GALEX All-Sky Imaging Survey (AIS), respectively. We augment these with deep Spitzer and GALEX imaging of galaxies in the 11 Mpc Local Volume Legacy (LVL) Survey, allowing us to extend these luminosity functions to lower luminosities (~10^6 L_⊙), and providing good constraints on the slope of the luminosity function at the extreme faint end for the first time. Using conventional star formation prescriptions, we generate from our data the star formation rate (SFR) distribution function for the local Universe. We find that it has a Schechter form, the faint-end slope has a constant value (to the limits of our data) of α=−1.51 ± 0.08 and the 'characteristic' SFR ψ^* is 9.2 M_⊙ yr^(−1). We also show the distribution function of the SFR volume density; we then use this to calculate a value for the total SFR volume density at z ~ 0 of 0.025 ± 0.0016 M_⊙ yr^(−1) Mpc^(−3), of which ~20 per cent is occurring in starbursts. Decomposing the total star formation by infrared luminosity, it can be seen that 9 ± 1 per cent is due to LIRGs, and 0.7 ± 0.2 per cent is occurring in ULIRGs. By comparing UV and IR emission for galaxies in our sample, we also calculate the fraction of star formation occurring in dust-obscured environments, and examine the distribution of dusty star formation: we find a very shallow slope at the highly extincted end, which may be attributable to line-of-sight orientation effects as well as conventional internal extinction

ALMA constraints on the faint millimetre source number counts and their contribution to the cosmic infrared background

We have analysed 18 ALMA continuum maps in Bands 6 and 7, with rms down to 7.8$\mu$Jy, to derive differential number counts down to 60$\mu$Jy and 100$\mu$Jy at $\lambda=$1.3 mm and $\lambda=$1.1 mm, respectively. The area covered by the combined fields is $\rm 9.5\times10^{-4}deg^2$ at 1.1mm and $\rm 6.6\times10^{-4}deg^{2}$ at 1.3mm. We improved the source extraction method by requiring that the dimension of the detected sources be consistent with the beam size. This method enabled us to remove spurious detections that have plagued the purity of the catalogues in previous studies. We detected 50 faint sources with S/N$>$3.5 down to 60$\mu$Jy, hence improving the statistics by a factor of four relative to previous studies. The inferred differential number counts are $\rm dN/d(Log_{10}S)=1\times10^5~deg^2$ at a 1.1 mm flux $S_{\lambda = 1.1~mm} = 130~\mu$Jy, and $\rm dN/d(Log_{10}S)=1.1\times10^5~deg^2$ at a 1.3 mm flux $\rm S_{\lambda = 1.3~mm} = 60~\mu$Jy. At the faintest flux limits, i.e. 30$\mu$Jy and 40$\mu$Jy, we obtain upper limits on the differential number counts of $\rm dN/d(Log_{10}S) < 7\times10^5~deg^2$ and $\rm dN/d(Log_{10}S)<3\times10^5~deg^2$, respectively. Our results provide a new lower limit to CIB intensity of 17.2${\rm Jy\ deg^{-2}}$ at 1.1mm and of 12.9${\rm Jy\ deg^{-2}}$ at 1.3mm. Moreover, the flattening of the integrated number counts at faint fluxes strongly suggests that we are probably close to the CIB intensity. Our data imply that galaxies with SFR$<40~M_{\odot}/yr$ certainly contribute less than 50% to the CIB while more than 50% of the CIB must be produced by galaxies with $\rm SFR>40~M_{\odot}/yr$. The differential number counts are in nice agreement with recent semi-analytical models of galaxy formation even as low as our faint fluxes. Consequently, this supports the galaxy evolutionary scenarios and assumptions made in these models.Comment: 11 pages, 9 figures, A&A accepte