The geography of entrepreneurship in the New York metropolitan area

This article was presented at a conference organized by the Federal Reserve Bank of New York in April 2005, "Urban Dynamics in New York City." The goal of the conference was threefold: to examine the historical transformations of the engine-of-growth industries in New York and distill the main determinants of the city's historical dominance as well as the challenges to its continued success; to study the nature and evolution of immigration flows into New York; and to analyze recent trends in a range of socioeconomic outcomes, both for the general population and recent immigrants more specifically.Business enterprises - New York (N.Y.) ; Economic conditions - New York (N.Y.) ; Federal Reserve District, 2nd ; Urban economics

Expert systems tools for Hubble Space Telescope observation scheduling

The utility of expert systems techniques for the Hubble Space Telescope (HST) planning and scheduling is discussed and a plan for development of expert system tools which will augment the existing ground system is described. Additional capabilities provided by these tools will include graphics-oriented plan evaluation, long-range analysis of the observation pool, analysis of optimal scheduling time intervals, constructing sequences of spacecraft activities which minimize operational overhead, and optimization of linkages between observations. Initial prototyping of a scheduler used the Automated Reasoning Tool running on a LISP workstation

Agglomeration, Labor Supply, and the Urban Rat Race

This paper establishes the existence of a previously overlooked relationship between agglomeration and hours worked. Among non-professionals, hours worked decrease with the density of workers in the same occupation. Among professionals, a positive relationship is found. This relationship is twice as strong for the young as for the middle-aged. Moreover, young professional hours worked are shown to be especially sensitive to the presence of rivals. We show that these patterns are consistent with the selection of hard workers into cities and the high productivity of agglomerated labor. The behavior of young professionals is also consistent with the presence of keen rivalry in larger markets, a kind of urban rat race. This evidence of a rat race is nearly unique in the literature

Acute kidney injury prediction in cardiac surgery patients by a urinary peptide pattern: a case-control validation study

Background Acute kidney injury (AKI) is a prominent problem in hospitalized patients and associated with increased morbidity and mortality. Clinical medicine is currently hampered by the lack of accurate and early biomarkers for diagnosis of AKI and the evaluation of the severity of the disease. In 2010, we established a multivariate peptide marker pattern consisting of 20 naturally occurring urinary peptides to screen patients for early signs of renal failure. The current study now aims to evaluate if, in a different study population and potentially various AKI causes, AKI can be detected early and accurately by proteome analysis. Methods Urine samples from 60 patients who developed AKI after cardiac surgery were analyzed by capillary electrophoresis-mass spectrometry (CE-MS). The obtained peptide profiles were screened by the AKI peptide marker panel for early signs of AKI. Accuracy of the proteomic model in this patient collective was compared to that based on urinary neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) ELISA levels. Sixty patients who did not develop AKI served as negative controls. Results From the 120 patients, 110 were successfully analyzed by CE-MS (59 with AKI, 51 controls). Application of the AKI panel demonstrated an AUC in receiver operating characteristics (ROC) analysis of 0.81 (95 % confidence interval: 0.72–0.88). Compared to the proteomic model, ROC analysis revealed poorer classification accuracy of NGAL and KIM-1 with the respective AUC values being outside the statistical significant range (0.63 for NGAL and 0.57 for KIM-1)

FUNCTIONAL HETEROGENEITY OF MURINE LYMPHOID CELLS : V. LYMPHOCYTES LACKING DETECTABLE SURFACE ϑ OR IMMUNOGLOBULIN DETERMINANTS

An appreciable percent (3–14%) of the lymphocyte-like cells of the mouse spleen lack both the θ-isoantigen and sufficient surface immunoglobulin to be detected by conventional immunofluorescence or autoradiographic procedures. These θ-,Ig- cells are increased in frequency after treatment of mice with antithymocyte serum or in mice that have been thymectomized, irradiated (850 R), and reconstituted with bone marrow cells. Moreover, in chimeric C57BL/6 mice in which the T cells are derived from (BALB/c x C57BL/6)F1 donors, θ-,Ig- cells also lack BALB/c histocompatibility antigens. These experiments indicate that θ-,Ig- cells are not θ- T lymphocytes. Removal of complement receptor lymphocytes from spleen cell populations increases the frequency of θ-,Ig- cells, indicating that such cells lack the complement receptor. Partially purified populations of θ-,Ig- cells have been obtained by cytolysis by anti-θ- and anti-κ-antibody and complement and by density gradient ultracentrifugation. These cells closely resemble lymphocytes in morphology. The only exceptional feature is the existence of prominent nucleoli. The θ-,Ig- cells lack hemoglobin and endogenous peroxidases, are not actively phagocytic, and do not adhere to glass. This suggests they are not of the erythroid, myeloid, or monocytoid lines. [3H]Thymidine labeling studies indicate that θ-,Ig- cells are members of a relatively slowly dividing cell pool. Whether θ-,Ig- cells are members of the "classical" B lymphocyte line or belong to another, as yet undescribed, lineage is not yet certain

Genetic snapshots of the Rhizobium species NGR234 genome

BACKGROUND: In nitrate-poor soils, many leguminous plants form nitrogen-fixing symbioses with members of the bacterial family Rhizobiaceae. We selected Rhizobium sp. NGR234 for its exceptionally broad host range, which includes more than I 12 genera of legumes. Unlike the genome of Bradyrhizobium japonicum, which is composed of a single 8.7 Mb chromosome, that of NGR234 is partitioned into three replicons: a chromosome of about 3.5 Mb, a megaplasmid of more than 2 Mb (pNGR234b) and pNGR234a, a 536,165 bp plasmid that carries most of the genes required for symbioses with legumes. Symbiotic loci represent only a small portion of all the genes coded by rhizobial genomes, however. To rapidly characterize the two largest replicons of NGR234, the genome of strain ANU265 (a derivative strain cured of pNGR234a) was analyzed by shotgun sequencing. RESULTS: Homology searches of public databases with 2,275 random sequences of strain ANU265 resulted in the identification of 1,130 putative protein-coding sequences, of which 922 (41%) could be classified into functional groups. In contrast to the 18% of insertion-like sequences (ISs) found on the symbiotic plasmid pNGR234a, only 2.2% of the shotgun sequences represent known ISs, suggesting that pNGR234a is enriched in such elements. Hybridization data also indicate that the density of known transposable elements is higher in pNGR234b (the megaplasmid) than on the chromosome. Rhizobium-specific intergenic mosaic elements (RIMEs) were found in 35 shotgun sequences, 6 of which carry RIME2 repeats previously thought to be present only in Rhizobium meliloti. As non-overlapping shotgun sequences together represent approximately 10% of ANU265 genome, the chromosome and megaplasmid may carry a total of over 200 RIMEs. CONCLUSIONS: 'Skimming' the genome of Rhizobium sp. NGR234 sheds new light on the fine structure and evolution of its replicons, as well as on the integration of symbiotic functions in the genome of a soil bacterium. Although most putative coding sequences could be distributed into functional classes similar to those in Bacillus subtilis, functions related to transposable elements were more abundant in NGR234. In contrast to ISs that accumulated in pNGR234a and pNGR234b, the hundreds of RIME elements seem mostly attributes of the chromosome

Towards Semi-Automated Annotation for Prepositional Phrase Attachment

This paper investigates whether high-quality annotations for tasks involving semantic disambiguation can be obtained without a major investment in time or expense. We examine the use of untrained human volunteers from Amazon’s Mechanical Turk in disambiguating prepositional phrase (PP) attachment over sentences drawn from the Wall Street Journal corpus. Our goal is to compare the performance of these crowdsourced judgments to the annotations supplied by trained linguists for the Penn Treebank project in order to indicate the viability of this approach for annotation projects that involve contextual disambiguation. The results of our experiments show that invoking majority agreement between multiple human workers can yield PP attachments with fairly high precision, confirming that this crowdsourcing approach to syntactic annotation holds promise for the generation of training corpora in new domains and genres