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The form of amniote claws has been extensively investigated, often with inferences about ecological association being drawn from studies of their geometry. Various methods have been used to quantify differences in the geometry of claws, but rarely have the underlying assumptions of such methods been addressed. Here, we use one set of bird claws and apply six methods (five that have been previously used, and a new one) that are tasked with comparing their shape. In doing so, we compare the (1) ability of these methods to represent the shape of the claw; (2) validity of the assumptions made about underlying claw geometry; (3) their ability to be applied unambiguously; and (4) their ability to differentiate between predetermined functional clusters. We find that of the six methods considered only the geometric morphometric approach reveals differences in the shapes of bird claws. Our comparison shows that geometry-based methods can provide a general estimate of the degree of curvature of claw arcs, but are unable to differentiate between shapes. Of all of the geometry-based approaches, we conclude that the adjusted version of the Zani (2000) method is the most useful because it can be applied without ambiguity, and provides a reliable estimate of claw curvature. The three landmarks that define that method (tip and base of the claw arc, plus the intersection between said claw arc and a line drawn perpendicular from the midpoint of tip and claw base) do not all bear biological significance, but relatively clearly circumscribe the length-to-height ratio of the claw, which relates to its curvature. Overall, our comparisons reveal that the shape of avian claws does not differ significantly between climbing and perching birds, and that the utilization of preordained functional clusters in comparative data analysis can hinder the discovery of meaningful differences in claw shape. J. Morphol. 278:150-169, 2017. © 2016 Wiley Periodicals,Inc.

We survey literature comparing inflation targeting (IT) and price-level targeting (PT) as macroeconomic stabilisation policies. Our focus is on New Keynesian models and areas that have seen significant developments since Ambler's (2009, Price-level targeting and stabilisation policy: a survey. Journal of Economic Surveys 23(5): 974–997) survey: optimal monetary policy; the zero lower bound; financial frictions and transition costs of adopting a PT regime. Ambler's conclusion that PT improves social welfare in New Keynesian models is fairly robust, but we note an interesting split in the literature: PT consistently outperforms IT in models where policymakers commit to simple Taylor-type rules, but results in favour of PT when policymakers minimise loss functions are overturned with small deviations from the baseline model. Since the beneficial effects of PT appear to hang on the joint assumption that agents are rational and the economy New Keynesian, we discuss survey and experimental evidence on rational expectations and the applied macro literature on the empirical performance of New Keynesian models. Overall, the evidence is not clear-cut, but we note that New Keynesian models can pass formal statistical tests against macro data and that models with rational expectations outperform those with behavioural expectations (i.e. heuristics) in direct statistical tests. We therefore argue that policymakers should continue to pay attention to PT.

Crises can be triggered by the inherent uncertainty of the capitalist system. We cannot pretend we can ever know the future, which is mired in Knightian uncertainty ('unknown unknowns'). Hence, in designing new regulative systems we need to avoid throwing the capitalist baby out with the risky bathwater.

Small carbon clusters C, C2 and C3 metallized with beryllium were studied by first principles within the hybrid density functional approach with generalized gradient correction. Cluster isomer structures for the ground state and several excited states where systematically calculated for CxBey with x = 1–3 and y = 1–4 including the vibrational analysis of all states. Ionization potentials and electron affinities are calculated for the ground state cluster isomers. The thermal stability of the ground state isomers was verified within the harmonic approximation of the Helmholtz free energy up to temperatures of about 1000 K. Within the family of clusters studied, C2Be3 undergoes a solid-like structural transition at about 260 K changing from a planar structure at low temperatures to a linear isomer at high temperatures. 2007 Elsevier B.V. All rights reserved.

Small carbon clusters metallized with Li were studied within a hybrid density functional approach with generalized gradient correction. Structures of the ground state and several excited states associated with different isomers and multiplicities were systematically calculated for CxLiy with x = 1–3 and y = 1–5. The most stable isomers are either linear or planar in the ground state. Three-dimensional structures are only identified for CLi4, CLi5, and C3Li4. There is important charge transfer in these compounds, showing that ionic bonding is favored as the cluster grows in size. Ionization potentials, electron affinities, and the vibrational analysis of all studied states is provided for all clusters. Structural transitions are predicted for C2Li2 at 1400 K and C2Li4 at 420 K.

The aim of this study was to develop techniques to sterilise the surface of silica gels containing encapsulated cells and the liquid broth they were immersed in, so that the observed metabolic activities could be unambiguously assigned to fully encapsulated cells. Gel surfaces were sterilised by UV-irradiation daily. The surfaces of the gels and the overlaying medium remained sterile for 20 days following irradiation, as demonstrated by the lack of visible surface growth and viable cells in the medium. We report the encapsulation of a viable, metabolically active, aerobic fungus Penicillium chrysogenum, and the aerobic Gram-positive bacterium Streptomyces rimosus in gels derived from aqueous silica sols. Carbohydrate consumption (catabolism) and antibiotic biosynthesis (penicillin or oxytetracycline) (anabolism) were monitored in both cultures, demonstrating that the encapsulated cells remained viable within the gel matrix. This demonstrates that the silica gels are sufficiently porous to sustain metabolic activities of aerobic cells, which require the diffusion of oxygen and other substrates within the gel’s nanopore network.

A technique was developed for differentiating the activity of microbes solely within sol gels by using the contribution of biomass outgrowth. Streptomyces rimosus was immobilised in colloidal silica gels and biomass growth, oxytetracycline synthesis, pH and carbohydrate consumption were compared for UV surface-sterilised gels, untreated gels, and liquid cultures. Absolute and biomass specific oxytetracycline yields were higher for non-sterile gels than for liquid culture. Biomass solely within colloidal silica gels (1.7 mg ml(-1)), and gels obtained from colloidal silica modified by addition of larger silica particles (1.2 mg ml(-1)) yielded 27 and 21 microg ml(-1) oxytetracycline compared with 97 and 104 microg ml(-1) for unsterilised gels (3.6 and 5.2 mg ml(-1) biomass) displaying outgrowth. It was therefore apparent that biomass and antibiotic production within the gels was limited and that optimisation requires gel modification.

Out-of-sample forecasting tests of DSGE models against time-series benchmarks such as an unrestricted VAR are increasingly used to check a) the specification b) the forecasting capacity of these models. We carry out a Monte Carlo experiment on a widely-used DSGE model to investigate the power of these tests. We find that in specification testing they have weak power relative to an in-sample indirect inference test; this implies that a DSGE model may be badly mis-specified and still improve forecasts from an unrestricted VAR. In testing forecasting capacity they also have quite weak power, particularly on the lefthand tail. By contrast a model that passes an indirect inference test of specification will almost definitely also improve on VAR forecasts.

The articles published in this special issue of Explorations in Economic History originated as papers presented at a three-day conference, “One Kind of Freedom Reconsidered: African-American Economic Life in the Segregation Era,” that was held at Lehigh University September 17–19, 1999. With more than 20 years having passed since Roger Ransom and Richard Sutch published One Kind of Freedom, it seemed an appropriate time to hold a conference that would bring together interested scholars in order both to reassess that book’s conclusions and to discuss further research on related themes. We were interested both in evaluating the work of Ransom and Sutch in relation to more recent scholarship and in extending the sophisticated, quantitative, and theoretically informed examination of black economic life beyond the postbellum South that had been the focus of Ransom and Sutch’s original work. Thus a number of the papers carry the story forward as the African-American population migrated from the rural agricultural South into the urbanized and industrialized North. Twenty-five years ago the research of economists into the history of African Americans was confined almost entirely to the study of slavery. The publication of One Kind of Freedom in 1977 represented a new departure. Based on extensive collections of new data, Ransom and Sutch persuasively demonstrated that “the economic institutions established in the postemancipation era effectively operated to keep the black population a landless agricultural labor force, operating tenant farms with backward and unprogressive technology. What little income was generated in excess of the bare essentials of life was exploited by monopolistic credit merchants.” But they went beyond this picture of the evils of sharecropping to insist as well that “the result of the economic advancements achieved by blacks since World War I is not, as we know all too well today, parity with whites. The progress made to date has been painfully slow. . . . The kind of freedom permitted black Americans today is still incomplete” (pp. 198–199). Immediately on publication, One Kind of Freedom set off a lively debate. Explorations in Economic History 38, 1–5 (2001) doi:10.1006/exeh.2000.0755, available online at http://www.idealibrary.com on

The extent of economic gains by African Americans in the decades after slavery is in dispute. Using a newly constructed data set, compiled from the manuscript census schedules and other sources, we find that African Americans in the Mississippi Delta experienced substantial income gains between 1880 and 1910. These gains can be attributed partly to African Americans moving into higher paying occupations—in particular, moving from being farm laborers to being farm operators—and partly to an increase in the incomes received from given occupations.

In recent years, the once conventional view that nominal wage rates were much more flexible before the Great Depression than after has been challenged. This challenge has been reinforced by several recent studies that are based on monthly wage data gathered by state labor bureaus. The surveys used by the state labor bureaus in gathering the data appear to have been biased toward the finding that wages have not changed. Hence inferences drawn from the data collected in these surveys are not reliable.

Strange as it seems, the infamous Smoot-Hawley Tariff might have had an expansionary effect on the U.S. economy. Basic macroeconomic principles indicate that the direct effect of a tariff increase is expansionary. This expansionary effect might be offset by retaliatory increases in foreign tariffs. Barry Eichengreen has recently questioned whether significant retaliation to Smoot-Hawley occurred. This article demonstrates that the tariff increases enacted during 1930 in Canada—the largest trading partner of the United States—were in direct response to Smoot-Hawley. The conventional wisdom that Smoot-Hawley hurt the U.S. economy may be right after all.

Producing and selling mechanically complex and expensive consumer durables involves a number of difficulties, especially if the products are manufactured in high volume. This paper focuses on the problem that companies employing high volume production methods are extremely vulnerable to the consequences of the variance in final sales across the business cycle, unless they devise methods for adjusting production to sales. Evidence is presented that it was the Ford Motor Company that first developed the methods required to ensure that production was kept in line with sales. These methods played a heretofore overlooked role in the success of Ford during its early years. General Motors was able to overtake Ford for leadership of the automobile industry only after it began to adopt similar methods, beginning in 1924.

The breast-shoulder apparatus (BSA) is a structurally and kinematically complex region of lizards. Compared with the pelvic region it has received little attention, even though its morphological variation is known to be extensive. This variability has seldom been the focus of functional explanation, possibly because the BSA has been difficult to explore as a composite entity. In this study we apply geometric morphometric techniques to the analysis of the BSA in an attempt to more fully understand its configuration in relation to differential use in locomotion. Our approach centers upon the Jamaican radiation of anoline lizards (genus Norops) as a tractable, small monophyletic assemblage consisting of species representing several ecomorphs. We hypothesized that the different species and ecomorphs would exhibit variation in the configuration of the BSA. Our findings indicate that this is so, and is expressed in the component parts of the BSA, although it is subtle except for Norops valencienni (twig ecomorph), which differs greatly in morphology (and behavior) from its island congeners. We further found similarities in the BSA of N. grahami, N. opalinus (both trunk-crown ecomorphs), and N. garmani (crown giant). These outcomes are promising for associating morphology with ecomorphological specialization and for furthering our understanding of the adaptive response of the BSA to demands on the locomotor system.

The UKs stagflation in the 1970s is decomposed into its causative factors, using the Liverpool rational expectations model. It is found that there was a large rise in the natural rate of unemployment, mainly due to rising union density; that fiscal and monetary shocks had little effect on the resulting rise in unemployment; and the high inflation of the period was due to persistent and large fiscal deficits, with their accompanying monetization. Mrs Thatcher inherited an inflation induced by an ongoing deficit and a natural rate of over 2 million unemployed.

This paper applies an algorithm for the solution of partial current information in rational expectation models to the quarterly Liverpool macroeconomic model of the U.K. The algorithm is shown to produce marginally superior results in forecasts both in ex-post and ex-ante forecasts and can be viewed as an additional tool for the forecaster's kit-bag.