Massive Optically Dark Galaxies Unveiled by JWST Challenge Galaxy Formation Models

Over the past decade, the existence of a substantial population of optically invisible, massive galaxies at $z\gtrsim3$ has been implied from mid-infrared to millimeter observations. With the unprecedented sensitivity of the JWST, such extremely massive galaxy candidates have immediately been identified even at $z>7$, in much larger numbers than expected. These discoveries raised a hot debate. If confirmed, early, high-mass galaxies challenge the current models of galaxy formation. However, the lack of spectroscopic confirmations leads to uncertain stellar mass ($M_{\star}$) estimates, and the possible presence of active galactic nuclei (AGN) adds further uncertainty. Here, we present the first sample of 36 dust-obscured galaxies with robust spectroscopic redshifts at $z_{\rm spec}=5-9$ from the JWST FRESCO survey. The three most extreme sources at $z\sim5-6$ ($\sim$1 billion years after the Big Bang) are so massive (log$M_{\star}/M_{\odot}$ $\gtrsim11.0$) that they would require, on average, about 50% of the baryons in their halos to be converted into stars -- two to three times higher than even the most efficient galaxies at later times. The extended emission of these galaxies suggests limited contribution by AGN. This population of ultra-massive galaxies accounts for 20% of the total cosmic star formation rate density at $z\sim5-6$, suggesting a substantial proportion of extremely efficient star formation in the early Universe.Comment: Submitted to Nature. 22 pages, 4 main figures, 7 supplementary figures, 3 supplementary tables. Comments are welcom

Insulin and hydrocortisone influences on cultured rat tongue epithelium

Rat tongue epithelium was separated from underlying connective tissue by trypsinization, dispersed into single cells and small clusters and plated on cellulose acetate-nitrate filters, collagen gels or plastic substrate in serum-supplemented media. Morphologically, abundance of growth and stratification of epithelium was greatest on floating collagen gels, intermediate on plastic and least on the filters. Cultures on the plastic substrate were used to test the effects of insulin, hydrocortisone, dimethyl sulphoxide, glucose and soybean trypsin inhibitor upon epithelial outgrowth. Cultures were plated at the same density, grown to partial con-fluency, and analysed with a superimposed point lattice to determine the fraction of total subsurface covered. Cells cultured 1.25 - 5 x 105 cells/cm2 in serum-supplemented [alpha]MEM or McCoy's 5A media produced the best outgrowth. Additional insulin supplementation at 40 [mu]g/ml gave better outgrowth than 400 or 4 [mu]g/ml within the first week. Insulin at 40 [mu]g/ml also gave better outgrowth than a mixed insulin-hydrocortisone supplement at three different levels or than hydrocortisone supplement alone at three different levels. When 0.5 per cent DMSO was added to any of these supplementary formulas, epithelial outgrowth was reduced compared with the same formulae without DMSO. Addition of three times the formula level of glucose also reduced epithelial outgrowth. Addition of soybean trypsin inhibitor to [alpha]MEM supplemented with insulin, but not fetal calf serum, caused increased epithelial outgrowth. These findings helped define appropriate conditions for cell attachment, migration, proliferation and differentiation of primary rat tongue epithelial cultures.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23749/1/0000722.pd

Converging and diverging governance mechanisms:the role of (dys) function in long-term inter-organizational relationships

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.This paper explores the dynamic interplay of formal/informal governance mechanisms, in terms of functional and dysfunctional consequences for both sides of the dyad, in long-term inter-organizational relationships. Using two longitudinal cases of UK defence sector procurement (warship commissioning) we move beyond notions of complementarity and substitution in governance towards a more nuanced view where the governance mix of inter-organizational relationships can be convergent or divergent. Our findings, showing that relationships can exhibit functional and dysfunctional behavior simultaneously, lead us to conclude that mismatches in governance mechanisms can be positive as well as negative. In building a context dependent understanding of governance we both summarize the (dys)functions associated with formal and informal governance mechanisms, and explore their impact on relationship exchange performance over time

The World Wide Web and Emerging Internet Resource Discovery Standards for Scholarly Literature

published or submitted for publicatio

Automated Cataloging: Implications for Libraries and Patrons

Many changes in cataloging practice have been and will increasingly be technology driven. Bound lists and drawers of cards defined the form and function of catalogs for as long as they existed until the advent of digital computers. Even today, however, MARC records are as much a derivative of catalog cards as the reverse. The additional functionality of computer catalogs affords opportunities to increase the effectiveness of the cataloging process and improve the value of the catalog itself. Three main research areas are examined with regard to their anticipated influence on this evolution. Automated cataloging research, focusing on the application of rule-based systems to cataloging, represents a novel way to address the cataloging process per se, but has as yet made only modest progress. The incremental implementation of a variety of computer-assisted methods for addressing aspects of cataloging represents a second, more conventional approach to advancing the state of the art in cataloging automation. This approach shares the goal of the first to build intelligent capabilities into cataloging systems but the focus remains on human cataloging systems and the methods of implementation are more conventional. The third area is not part of traditional concepts of cataloging at all, but will have a major impact upon what is available in catalogs in the broadest sense of that term. This "non traditional" cataloging involves automated processing of documents to extract bibliographic information as well as full text. It will expand the range of cataloged objects to include items not generally cataloged due to resource constraints. Automated processing of such materials will be characterized by lower quality and less complete cataloging, but will nonetheless promote improved access to materials that are currently lost to bibliographic control.published or submitted for publicatio

A framework for understanding indentifiers and "info" URIs

Overview of Info URI

The Dublin core metadata initiative : DC-8 and the year 2000 in review

http://library.naist.jp/mylimedio/dllimedio/show.cgi?bookid=100028497&oldid=3109

Issues in Managing Persistent Identifiers [Thoughts on identifiers]

As business processes and information transactions have become an inextricably intertwined with the Web, the importance of assignment, registration, discovery, and maintenance of identifiers has increased. In spite of this, integrated frameworks for managing identifiers have been slow to emerge. Instead, identification systems arise (quite naturally) from immediate business needs without consideration for how they fit into larger information architectures. In addition, many legacy identifier systems further complicate the landscape, making it difficult for content managers to select and deploy identifier systems that meet both the business case and long term information management objectives. This presentation will outline a model for evaluating identifier applications and the functional requirements of the systems necessary to support them. The model is based on a layered analysis of the characteristics of identifier systems, including: Functional characteristics; Technology; Policy; Business; Social. These layers afford a useful outline for framing discussions and evaluation of identifier systems