Hexabundles: imaging fiber arrays for low-light astronomical applications

We demonstrate a novel imaging fiber bundle ("hexabundle") that is suitable for low-light applications in astronomy. The most successful survey instruments at optical-infrared wavelengths use hundreds to thousands of multimode fibers fed to one or more spectrographs. Since most celestial sources are spatially extended on the celestial sphere, a hexabundle provides spectroscopic information at many distinct locations across the source. We discuss two varieties of hexabundles: (i) lightly fused, closely packed, circular cores; (ii) heavily fused non-circular cores with higher fill fractions. In both cases, we find the important result that the cladding can be reduced to ~2 μm over the short fuse length, well below the conventional ~10λ thickness employed more generally, with a consequent gain in fill factor. Over the coming decade, it is to be expected that fiber-based instruments will be upgraded with hexabundles in order to increase the spatial multiplex capability by two or more orders of magnitude

Climatology of size, shape and intensity of precipitation features over Great Britain and Ireland

A climatology of precipitation features (or objects) from the Great Britain and Ireland radar-derived precipitation mosaic from 2006–2015 is constructed, with features defined as contiguous areas of nonzero precipitation rates. Over the ten years, there are 54,811,747 non-unique precipitating features over 100 km2 in area, with a median precipitation-feature area of 249 km2, median major axis length of 29.2 km, median aspect ratio of 2.0, median feature mean precipitation rate of 0.49 mm h-1, and median feature maximum precipitation rate of 2.4 mm h-1. Small-scale precipitating systems are most common, but larger systems exceeding 10,000 km2 contribute close to 70% of the annual precipitation across the study region. Precipitation feature characteristics are sensitive to changes in annual and diurnal environment, with feature intensities peaking during the afternoon in summer and the largest precipitation features occurring during winter. Precipitation intensities less than 5 mm h-1 comprise 97.3% of all precipitation occurrence and contribute 83.6% of the total precipitation over land. Banded-precipitation features (defined as precipitation features with aspect ratio at least 3:1 and major axis length at least 100 km) comprise 3% of all precipitation features by occurrence, but contribute 23.7% of the total precipitation. Mesoscale banded features (defined as banded-precipitation features with major axis length at least 100 km and total area not exceeding 10,000 km2) and mesoscale convective banded features (defined as banded-precipitation features with at least 100 km2 of precipitation rates exceeding 10 mm h-1) are most prevalent in southwestern England with mesoscale convective banded features contributing up to 2% of precipitation

Ernst Freund as Precursor of the Rational Study of Corporate Law

Gindis, David, Ernst Freund as Precursor of the Rational Study of Corporate Law (October 27, 2017). Journal of Institutional Economics, Forthcoming. Available at SSRN: https://ssrn.com/abstract=2905547, doi: https://dx.doi.org/10.2139/ssrn.2905547The rise of large business corporations in the late 19th century compelled many American observers to admit that the nature of the corporation had yet to be understood. Published in this context, Ernst Freund's little-known The Legal Nature of Corporations (1897) was an original attempt to come to terms with a new legal and economic reality. But it can also be described, to paraphrase Oliver Wendell Holmes, as the earliest example of the rational study of corporate law. The paper shows that Freund had the intuitions of an institutional economist, and engaged in what today would be called comparative institutional analysis. Remarkably, his argument that the corporate form secures property against insider defection and against outsiders anticipated recent work on entity shielding and capital lock-in, and can be read as an early contribution to what today would be called the theory of the firm.Peer reviewe

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Introduction To Agricultural Economics

xiii+556hal.;22c

History of agriculture in the southern United States to 1860 /

Paged continuouslyIncludes bibliographical references (pages 945-1016) and indexVolume 2: Part V, The Development of National Economy. Agricultural Conditions During the Revolutionary Period -- Agricultural Readjustment, 1783-1795 -- Post Colonial Land Policy and Tenure -- Changes in the Supply of Slave Labor -- Part VI, Agricultural Industries and Husbandry in the Post Colonial Period. Beginnings of the Cotton Industry, 1785-1814 -- Short-Staple Cotton, 1815-1860 -- The Minor Staples in the Post Colonial Period-Rice, Sea-Island Cotton, and Sugar -- The Tobacco Industry, 1795-1860 -- Technical Progress of Crop Husbandry in the Post Colonial Period -- General Farm Crops -- Livestock Husbandry in the Post Colonial Period -- Part VII, Geographic Expansion and Regional Development. Transmontane Expansion of General Farming -- Expansion of the Plantation System on the Basis of Cotton, 1815-1860 -- Agriculture in the Wake of Expansion -- The Attempted Readjustment of Southern Economic Life -- Bibliography -- Appendix -- IndexVolume 1: Part I, Agricultural Beginnings and Geographic Expansion. Agriculture Before the Coming of the English -- The Beginnings and Development of Agriculture in Virginia and Maryland -- Beginnings of Agriculture in the Carolinas -- Agriculture in the Lower Mississippi Valley and Gulf Coastal Plain in the Eighteenth Century -- Further Agricultural Expansion in the Colonial Period -- Part II, Agricultural Industries in the Colonial Period. Pioneer Stages of Economic Activity: The Indian Trade, Herding, and Naval Stores and Lumbering -- Grain Crops -- Minor Crops and General Crop Husbandry -- Livestock Husbandry -- Growth of the Colonial Tobacco Industry and Conditions of Production and Exportation -- Colonial Tobacco in the Foreign Market -- The Tobacco Industry-Price Fluctuations and Variations in Prosperity -- Rice and Indigo -- Part III, Institutional Development in the Colonial Period. Genesis of the Plantation System as an Agency for Colonial Expansion of Capitalism -- Early Evolution of the Plantation System-Transition from Corporate to Individual Initiative -- Development of the Labor Bases of the Colonial Plantation System -- The Colonial Land System -- Credit and Marketing -- Part IV, Economic Evolution in the South. General Tendencies in Economic Evolution -- Economic Efficiency and Competitive Advantages of Negro Slavery under the Plantation System -- Economic Types and Social Classes-The Whites -- Economic Types and Social Classes-The Blacks -- Extent and Character of Plantation Organization in the Post Colonial Period -- Organization and Management of Slave LaborMode of access: Internet

Farm land values in Iowa /

no.874 (1920

Buying farms with land-bank loans : a study based on the experience of 2,700 farmers who have borrowed money through federal farm loan banks /

no.968 (1921

Land settlement and colonization in the Great Lakes states /

no.1295 (1925