7,900 research outputs found
Sugar Maple Borer (Coleoptera: Cerambycidae) Activity Associated With Periods of Severe Defoliation
A perusal of previous research on sugar maple borer, Glycobius speciosus, in northern New York State strongly associates severe early and late season defoliation with increased borer damage. This re-examination of earlier work suggests foliage protection may be necessary when forest management objectives are concerned with wood volume and quality
Was there an ‘Industrious Revolution’ before the Industrial Revolution? An Empirical Exercise for England, c. 1300-1830
It is conventionally assumed that the pre-modern working year was fixed and that consumption varied with changes in wages and prices. This is challenged by the twin theories of the ‘industrious’ revolution and the consumer revolution, positing a longer working year as people earned surplus money to buy novel goods. In this study, we turn the conventional view on its head, fixing consumption rather than labour input. Specifically, we use a basket of basic consumption goods and compute the working year of rural and urban day labourers required to achieve that. By comparing with independent estimates of the actual working year, we find two ‘industrious’ revolutions among rural workers; both, however, are attributable to economic hardship, and we detect no signs of a consumer revolution. For urban labourers, by contrast, a growing gap between their actual working year and the work required to buy the basket provides great scope for a consumer revolution.Consumer Revolution; Cost-of-Living Index; Day Wages; ‘Industrious’ Revolution; Industrial Revolution; Labour Supply; Standard of Living
Revolución en los campos: La reinterpretación de la Revolución Agrícola inglesa
Nuestra comprensión de los open fields y de los cercamientos ha experimentado una revolución en las últimas décadas. Un considerable número de investigaciones ha mostrado que los campesinos acomodados y las pequeñas explotaciones fueron capaces de innovar, y los open fields fueron testimonio de la mayor parte del crecimiento de los rendimientos y la productividad experimentado por la agricultura inglesa desde la Edad Media hasta mediados del siglo XVIII. De 1750 en adelante, los cercamientos parlamentarios aumentaron las rentas de la aristocracia o la pequeña nobleza, pero no lograron incrementar significativamente el producto agrario ni liberar trabajo en cantidades apreciables. Los primeros pasos del nuevo planteamiento surgieron de comparaciones estadisticas o análisis de regresión, y no de las fuentes documentales empleadas para sostener la visión convencional. Sin embargo, las pruebas en favor de la capacidad de progreso de los open fields también pueden encontrarse en las fuentes tradicionales.Our understanding of the open fields and enclosures has been revolutionised in recent decades. A wide range of research has shown that yeomen farmers and small holders peasants were capable of innovation, and the open fields witnessed most of the output and productivity growth achieved by English agriculture from the Middle Ages to around 1750. Parliamentary enclosures increased landlord and gentry income, but often failed to produce much extra output or release much labour from 1750 onwards. The first steps of the new understanding arose from statistical comparisons and regression analysis rather than from the documentary data used to support the standard approach. But the case for the progressiveness of the open fields can also be built in traditional sources
Recent developments in production, cost, and index number theory, with an application to international differences in the cost and efficiency of steelmaking in 1907/9
"Dieser Beitrag stellt neuere Entwicklungen in der Theorie der Produktions- und Kostenfunktionen sowie der Theorie der Indexziffern zusammenfassend dar. Die Indexzifferntheorie bietet das nötige Instrumentarium, um Probleme zu lösen, denen sich Wirtschaftshistoriker schon lange gegenübersahen. Hier wurden diese Methoden angewendet, um die Kostenunterschiede bei der Stahlherstellung in Deutschland, Großbritannien und in den Vereinigten Staaten in den Jahren 1907 und 1909 zu analysieren. Dabei ergab sich, daß sowohl die amerikanische als auch die deutsche Stahlindustrie um 15 Prozent effizienter produzierten als die britische. Darüber hinaus vermochte Deutschland seine Position auf dem Weltmarkt noch durch besonders niedrige Inputpreise zu verbessern, während Amerika seinen Produktivitätsvorteil durch das dort vorherrschende hohe Lohnniveau ziemlich wieder einbüßte." (Autorenreferat
Essence of Reducing Equivalent Transfer Powering Neutrophil Oxidative Microbicidal Action and Chemiluminescence
Neutrophil leukocytes provide first-line phagocytic defense against infection. Phagocyte locomotion to the site of infection, identification, and phagocytosis of the infecting microbe results in metabolically driven O2-dependent combustive microbicidal action. NADPH oxidase activity controls this respiratory burst metabolism. Its flavoenzyme character allows semiquinone-mediated crossover from two reducing equivalents (2RE) to 1RE transfer, as is necessary for univalent reduction of O2 to the acid hydroperoxyl radical (HO2) and its conjugate base, superoxide anion (O2−). RE transfer dynamics is considered from the perspectives of quantum and particle physics, as well as frontier orbital interactions. Direct disproportionation of HO2-O2− yields electronically excited singlet molecular oxygen (1O2*) and hydrogen peroxide (H2O2). Myeloperoxidase catalyzes H2O2-dependent 2RE oxidation of chloride (Cl−) to hypochlorite (OCl−). Direct nonenzymatic reaction of OCl− with an additional H2O2 yields Cl−, H2O, and 1O2*. Thus, for two 2RE metabolized through NADPH oxidase, a total of three 1O2* are possible. H2O2, OCl−, and 1O2* generated are all singlet multiplicity reactants and can participate in spin-allowed combustive oxygenations yielding light emission, that is, luminescence or chemiluminescence. The sensitivity of luminescence for measuring neutrophil redox activities is increased several orders of magnitude by introducing chemiluminigenic probes. Probes can be selected to differentiate oxidase from haloperoxidase activities
The azimuthal component of Poynting's vector and the angular momentum of light
The usual description in basic electromagnetic theory of the linear and angular momenta of light is centred upon the identification of Poynting's vector as the linear momentum density and its cross product with position, or azimuthal component, as the angular momentum density. This seemingly reasonable approach brings with it peculiarities, however, in particular with regards to the separation of angular momentum into orbital and spin contributions, which has sometimes been regarded as contrived. In the present paper, we observe that densities are not unique, which leads us to ask whether the usual description is, in fact, the most natural choice. To answer this, we adopt a fundamental rather than heuristic approach by first identifying appropriate symmetries of Maxwell's equations and subsequently applying Noether's theorem to obtain associated conservation laws. We do not arrive at the usual description. Rather, an equally acceptable one in which the relationship between linear and angular momenta is nevertheless more subtle and in which orbital and spin contributions emerge separately and with transparent forms
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