Učenje v poznejših letih: univerze, poučevanje, medgeneracijsko učenje in kohezivnost skupnosti

There are no settled concepts in the field of learning in later life. The paper begins by suggesting that generalised statements about older people’s learning are suspect and that the way in which we talk about it shifts over time. In particular, there is a range of claims about methods of learning and teaching appropriate to older people but most have little support from empirical research. The paper then focuses on the evaluation of a small innovation project, funded by national government, at Lancaster University, 2009-10. The project sought to involve members of a local University of the Third age group in learning activity on the nearby university campus, partly using undergraduate teaching provision. It aimed to test ideological reservations within the U3A group about association with a public institution of higher education and about mixing the ‘purity’ of self-help learning for older adults, in the British U3A tradition, with more formal methods of learning. The outcomes of the project evaluation suggested that most older learners participating valued their opportunity to use university learning resources and that the British U3A ideology did not inhibit them from doing so. It also suggests that the University benefited from the presence of the older learners and that the surrounding community potentially might have done. A brief discussion of implications for intergenerational learning, community cohesion and marginalised older people follows. The paper concludes that British universities should and, perhaps, could relate more dynamically and emphatically with the provision of opportunities for learning in later life.Na področju učenja v poznejših letih ni ustaljenih pojmov. Članek sprva opozori, da posplošitvam o učenju starejših ne kaže zaupati in da se načini obravnave spreminjajo skozi čas. Srečujemo se z vrsto trditev o tem, kateri načini učenja in poučevanja naj bi bili primerni za starejše, vendar je za večino v empiričnih raziskavah najti le malo podpore. Članek se potem usmeri na oceno manjšega inovativnega projekta, ki je potekal na Univerzi Lancaster v letih 2009/10 in ga je financirala britanska vlada. V projektu so skušali člane skupine lokalne univerze za tretje življenjsko obdobje pritegniti k učnim dejavnostim v bližnjem univerzitetnem centru, pri čemer so uporabili študijsko ponudbo na preddiplomski stopnji. Namen projekta je bil preveriti pomisleke, ki naj bi jih imeli člani univerze za tretje življenjsko obdobje glede povezave z javno visokošolsko ustanovo in s tem izgube »čistosti« načela samopomoči pri učenju starejših, značilnega za britanske univerze za tretje življenjsko obdobje, na račun bolj formalnih oblik učenja. Rezultati raziskave so pokazali, da je večina starejših, ki so bili vključeni v projekt, cenila možnost uporabe univerzitetnih učnih virov in da jih ideologija britanskih univerz za tretje življenjsko obdobje pri tem ni ovirala. Nadalje se kaže, da je s prisotnostjo starejših pridobila tudi univerza, morda pa tudi okoliška skupnost. Sledi krajša razprava o pomenu teh ugotovitev za medgeneracijsko učenje, za kohezivnost skupnosti in za marginalizirane starejše. Članek se zaključi z mislijo, da bi se britanske univerze morale oz. mogle bolj dinamično in izrazito zavzeti za odpiranje učnih možnosti za starejše

Fast Outflows in Hot Dust-obscured Galaxies Detected with Keck/NIRES

We present rest-frame optical spectroscopic observations of 24 Hot Dust-Obscured Galaxies (Hot DOGs) at redshifts 1.7–4.6 with KECK/NIRES. Our targets are selected, based on their extreme red colors, to be the highest-luminosity sources from the WISE infrared survey. In 20 sources with well-detected emission, we fit the key [O iii], Hβ, Hα, [N ii], and [S ii] diagnostic lines to constrain physical conditions. Of the 17 targets with a clear detection of the [O iii]λ5007 Å emission line, 15 display broad blueshifted and asymmetric line profiles, with widths ranging from 1000 to 8000 km s⁻¹ and blueshifts up to 3000 km s⁻¹. These kinematics provide strong evidence for the presence of massive ionized outflows of up to 8000 M_ ⊙ yr⁻¹, with a median of 150 M_ ⊙ yr⁻¹. As many as eight sources show optical emission line ratios consistent with vigorous star formation. Balmer-line star formation rates, uncorrected for reddening, range from 30 to 1300 M_ ⊙ yr⁻¹, with a median of 50 M_ ⊙ yr⁻¹. Estimates of the SFR from Spectral Energy Distribution fitting of mid- and far-infrared photometry suggest significantly higher values. We estimate the central black hole masses to be of order 10⁸⁻¹⁰ M_ ⊙, assuming the present-day M_(BH)-σ_★ relation. The bolometric luminosities and the estimated masses of the central black holes of these galaxies suggest that many of the active galactic nucleus-dominated Hot DOGs are accreting at or above their Eddington limit. The combination of ongoing star formation, massive outflows, and high Eddington ratios suggest Hot DOGs are a transitional phase in galaxy evolution

Fast Outflows in Hot Dust-obscured Galaxies Detected with Keck/NIRES

We present rest-frame optical spectroscopic observations of 24 Hot Dust-Obscured Galaxies (Hot DOGs) at redshifts 1.7–4.6 with KECK/NIRES. Our targets are selected, based on their extreme red colors, to be the highest-luminosity sources from the WISE infrared survey. In 20 sources with well-detected emission, we fit the key [O iii], Hβ, Hα, [N ii], and [S ii] diagnostic lines to constrain physical conditions. Of the 17 targets with a clear detection of the [O iii]λ5007 Å emission line, 15 display broad blueshifted and asymmetric line profiles, with widths ranging from 1000 to 8000 km s⁻¹ and blueshifts up to 3000 km s⁻¹. These kinematics provide strong evidence for the presence of massive ionized outflows of up to 8000 M_ ⊙ yr⁻¹, with a median of 150 M_ ⊙ yr⁻¹. As many as eight sources show optical emission line ratios consistent with vigorous star formation. Balmer-line star formation rates, uncorrected for reddening, range from 30 to 1300 M_ ⊙ yr⁻¹, with a median of 50 M_ ⊙ yr⁻¹. Estimates of the SFR from Spectral Energy Distribution fitting of mid- and far-infrared photometry suggest significantly higher values. We estimate the central black hole masses to be of order 10⁸⁻¹⁰ M_ ⊙, assuming the present-day M_(BH)-σ_★ relation. The bolometric luminosities and the estimated masses of the central black holes of these galaxies suggest that many of the active galactic nucleus-dominated Hot DOGs are accreting at or above their Eddington limit. The combination of ongoing star formation, massive outflows, and high Eddington ratios suggest Hot DOGs are a transitional phase in galaxy evolution

Innovations and advances in instrumentation at the W. M. Keck Observatory

Since the start of operations in 1993, the twin 10 meter W. M. Keck Observatory telescopes have continued to maximize their scientific impact and to produce transformative discoveries that keep the observing community on the frontiers of astronomical research. Upgraded capabilities and new instrumentation are provided though collaborative partnerships with Caltech and UC instrument development teams. The observatory adapts and responds to the observers’ evolving needs as defined in the observatory’s strategic plan, periodically refreshed in collaboration with the science community. This paper summarizes the performance of recently commissioned infrastructure projects, technology upgrades, and new additions to the suite of instrumentation at the observatory. We will also provide a status of projects currently in the design or development phase, and since we need to keep our eye on the future, we mention projects in exploratory phases that originate from our strategic plan. Recently commissioned projects include telescope control system upgrades, OSIRIS spectrometer and imager upgrades, and deployments of the Keck Cosmic Web Imager (KCWI), the Near-Infrared Echellette Spectrometer (NIRES), and the Keck I Deployable Tertiary Mirror (KIDM3). Under development are upgrades to the NIRSPEC instrument and adaptive optics (AO) system. Major instrumentation in design phases include the Keck Cosmic Reionization Mapper and the Keck Planet Finder. Future instrumentation studies and proposals underway include a Ground Layer Adaptive Optics system, NIRC2 upgrades, the energy sensitive instrument KRAKENS, an integral field spectrograph LIGER, and a laser tomography AO upgrade. Last, we briefly discuss recovering MOSFIRE and its return to science operations

The medical student

The Medical Student was published from 1888-1921 by the students of Boston University School of Medicine

Galaxy ecology: groups and low-density environments in the SDSS and 2dFGRS

We analyse the observed correlation between galaxy environment and Hα emission-line strength, using volume-limited samples and group catalogues of 24 968 galaxies at 0.05 < z < 0.095, drawn from the 2dF Galaxy Redshift Survey ( < −19.5) and the Sloan Digital Sky Survey (Mr < −20.6). We characterize the environment by: (1) Σ5, the surface number density of galaxies determined by the projected distance to the fifth nearest neighbour; and (2) ρ1.1 and ρ5.5, three-dimensional density estimates obtained by convolving the galaxy distribution with Gaussian kernels of dispersion 1.1 and 5.5 Mpc, respectively. We find that star-forming and quiescent galaxies form two distinct populations, as characterized by their Hα equivalent width, W0(Hα). The relative numbers of star-forming and quiescent galaxies vary strongly and continuously with local density. However, the distribution of W0(Hα) amongst the star-forming population is independent of environment. The fraction of star-forming galaxies shows strong sensitivity to the density on large scales, ρ5.5, which is likely independent of the trend with local density, ρ1.1. We use two differently selected group catalogues to demonstrate that the correlation with galaxy density is approximately independent of group velocity dispersion, for σ= 200-1000 km s-1. Even in the lowest-density environments, no more than ∼70 per cent of galaxies show significant Hα emission. Based on these results, we conclude that the present-day correlation between star formation rate and environment is a result of short-time-scale mechanisms that take place preferentially at high redshift, such as starbursts induced by galaxy-galaxy interaction

Galaxy ecology: groups and low-density environments in the SDSS and 2dFGRS

We analyse the observed correlation between galaxy environment and Hα emission-line strength, using volume-limited samples and group catalogues of 24 968 galaxies at 0.05 < z < 0.095, drawn from the 2dF Galaxy Redshift Survey (M_(bJ) < −19.5) and the Sloan Digital Sky Survey (Mᵣ < −20.6). We characterize the environment by: (1) Σ₅, the surface number density of galaxies determined by the projected distance to the fifth nearest neighbour; and (2) ρ1.1 and ρ5.5, three-dimensional density estimates obtained by convolving the galaxy distribution with Gaussian kernels of dispersion 1.1 and 5.5 Mpc, respectively. We find that star-forming and quiescent galaxies form two distinct populations, as characterized by their Hα equivalent width, W₀(Hα). The relative numbers of star-forming and quiescent galaxies vary strongly and continuously with local density. However, the distribution of W₀(Hα) amongst the star-forming population is independent of environment. The fraction of star-forming galaxies shows strong sensitivity to the density on large scales, ρ5.5, which is likely independent of the trend with local density, ρ1.1.We use two differently selected group catalogues to demonstrate that the correlation with galaxy density is approximately independent of group velocity dispersion, for σ = 200–1000 km s⁻¹. Even in the lowest-density environments, no more than ∼70 per cent of galaxies show significant Hα emission. Based on these results, we conclude that the present-day correlation between star formation rate and environment is a result of short-time-scale mechanisms that take place preferentially at high redshift, such as starbursts induced by galaxy–galaxy interactions

Enzymatically oxidized phospholipids restore thrombin generation in coagulation factor deficiencies

Hemostatic defects are treated using coagulation factors; however, clot formation also requires a procoagulant phospholipid (PL) surface. Here, we show that innate immune cell–derived enzymatically oxidized phospholipids (eoxPL) termed hydroxyeicosatetraenoic acid–phospholipids (HETE-PLs) restore hemostasis in human and murine conditions of pathological bleeding. HETE-PLs abolished blood loss in murine hemophilia A and enhanced coagulation in factor VIII- (FVIII-), FIX-, and FX-deficient human plasma . HETE-PLs were decreased in platelets from patients after cardiopulmonary bypass (CPB). To explore molecular mechanisms, the ability of eoxPL to stimulate individual isolated coagulation factor/cofactor complexes was tested in vitro. Extrinsic tenase (FVIIa/tissue factor [TF]), intrinsic tenase (FVIIIa/FIXa), and prothrombinase (FVa/FXa) all were enhanced by both HETE-PEs and HETE-PCs, suggesting a common mechanism involving the fatty acid moiety. In plasma, 9-, 15-, and 12-HETE-PLs were more effective than 5-, 11-, or 8-HETE-PLs, indicating positional isomer specificity. Coagulation was enhanced at lower lipid/factor ratios, consistent with a more concentrated area for protein binding. Surface plasmon resonance confirmed binding of FII and FX to HETE-PEs. HETE-PEs increased membrane curvature and thickness, but not surface charge or homogeneity, possibly suggesting increased accessibility to cations/factors. In summary, innate immune-derived eoxPL enhance calcium-dependent coagulation factor function, and their potential utility in bleeding disorders is proposed