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This paper extends Turing analysis to standard recursive optimal control frameworks in economics and applies it to dynamic bioeconomic problems where the interaction of coupled economic and ecological dynamics under optimal control over space creates (or destroys) spatial heterogeneity. We show how our approach reduces the analysis to a tractable extension of linearization methods applied to the spatial analog of the well known costate/state dynamics. We explicitly show the existence of a non-empty Turing space of diffusive instability by developing a linear-quadratic approximation of the original non-linear problem. We apply our method to a bioeconomic problem, but the method has more general economic applications where spatial considerations and pattern formation are important. We believe that the extension of Turing analysis and the theory associated with the dispersion relationship to recursive infinite horizon optimal control settings is new.

The purpose is to identify biological markers that predict brain metastasis and treatment outcome in non-small cell lung cancer (NSCLC).Samples were obtained from the primary tumors, lymph nodes, and brain metastases of 29 patients with NSCLC who had undergone resection of both the pulmonary tumors and the brain lesions. Samples from 29 patients matched for age, sex, and histology whose pulmonary tumors were resected served as controls. Samples were stained with HE as well as immunohistochemical stains for epidermal growth factor receptor (EGFR), cyclooxygenase 2 (COX-2), and BAX. Comparisons were made between patients with and without brain metastasis. Independent investigators determined the percentage of positive cells.There was positive correlation in expression of all three biomarkers between primary lung tumors and lymph node metastases. Significantly higher levels of EGFR were found in lymph node metastases in the control group (P = 0.0147). COX-2 expression in brain lesions correlated with expression in primary tumors (P = 0.023). BAX levels were lower in poorly differentiated tumors in lymph node metastases in the control group (P = 0.01) and in brain metastases (P = 0.045). Low EGFR expression and high COX-2 expression in lymph node metastasis were associated with poorer treatment outcome.Expression of EGFR, COX-2, and BAX in primary lung tumors did not differ between patients with brain metastases from NSCLC and those without brain metastases. These three biomarkers cannot be used to predict brain metastasis. Studies of other biomarkers are under way in an effort to predict brain metastasis among patients with NSCLC.

This paper describes a range of methods which have been proposed to study interactions in economic and social contexts. By interactions, we refer to interdependences between individual decisions which are not mediated by markets. These types of models have been employed to understand phenomena ranging from the effect of neighborhoods on the life prospects of children to the evolution of political party platforms. We provide a general choice-based framework for modeling such interactions which subsumes a number of specific models which have been studied. This framework illustrates the relationship between interactions-based models and models in statistical mechanics. Our analysis is then extended to the econometrics of these models, with an emphasis on the identification of group-level influences on individual behavior. Finally, we review some of the empirical work on interactions which has appeared in the social science literature.

Reactive volatile organic compounds VOCs play a major role in the formation of photo- chemical oxidants in the atmosphere by reacting with oxides of nitrogen and solar ultraviolet energy pro- ducing ozone, which is a criteria pollutant regulated under the National Ambient Air Quality Standards. The United States is one of the most agriculturally productive countries in the world due in part to the use of chemical pesticides that consist of active ingredients that are typically non-volatile or semi-VOCs and inert ingredients such as solvents, emulsifiers, and diluents that may also be volatile. Presently, the VOC deter- mination of emission factors from agricultural pesticide applications assumes that all of the inert VOC ingredients volatilize. This research focuses on the development of a laboratory methodology for applying agricultural spray formulations in accurate and measurable levels to support VOC deposition onto and loss from soil surfaces. Adapting a laboratory spray table system with a modified spray and deposition sampling scheme resulted in repeatable spray applications, with the deposition pattern being mapped across the treatment area. These mapped deposition values allow for measurements from soil samples to be corre- lated with actual spray deposition. This methodology provides for a rapid and repeatable means for sur- veying VOC deposition and losses from a variety of spray formulations under varying spray rates and spray droplet sizes.

Elites in American History is a massive work in three volumes of which two have been received for review. It investigates the economic associations of every cabinet minister, every minister to Great Britain and France, and every justice of the Supreme Court since Washington's first administration. In recent times these are supplemented by ministers to other countries, some assistant secretaries, and the heads of some federal agencies. The opinions printed on the dust cover promise an enthusiastic reception. "A magnificent work of careful scholarship," writes Robert Presthus, while for G. William Domhoff it will be "a focus of scholarly debate for years to come." William Appleman Williams is more restrained when he says that "Mr Burch has researched and made available ... a wide range of important data," but for Edward Pessen it is "one of the most significant pieces of work in the past fifty years on the subject of politics and society in America." The journal Choice described it as "monumentally verbal, historical, and inter pretive. . . . For all four-year college and university libraries." Passing over the conceptual difficulty presented by the phrase "monumentally verbal," it seems that these recommendations should make the three volumes required reading for all courses devoted to the newer than new political history. In selecting men for office a President is likely to look for successful and experienced men in good standing with their peers. In a country without a heredi tary aristocracy it is predictable that the majority of men with these qualifications will be bankers, merchants, and highly-paid lawyers. Before i860 a large number

In 1828 and 1832 James Fenimore Cooper visited England. He expected hostility because he had just writtenNotions of the Americanswhich was intended to correct the erroneous statements of British travellers about the United States, but during his visits he was well received and managed to meet many leading literary and political figures. Yet everything was wrong. In 1837 he published a book based on these visits and expressed his dismay at ‘the extent of the malignancy, or the nature of the falsehood, that are industriously circulated here at the expense of America’. It was, he wrote, a country that I could fain like, but whose prejudices and national antipathies throw a chill over all my affections; a country that unquestionably stands at the head of civilization in a thousand things, but which singularly exemplifies a truth we all acknowledge, – how much easier it is to possess great and useful, and even noble qualities, than to display those that are attractive and winning; – a country that all respect, but few love.

Several predictors of tumor radiocurability are already integrated into clinical practice, e.g., tumor size, gross morphologic features (i.e., infiltrative or exophytic), histologic type, and grade. These are relatively imprecise, however, and none is specific. The aim of research into predictive assays is not only to refine the discrimination of existing predictors but also to suggest specific experimental approaches for overcoming tumor radioresistance in individual patients. Two broad categories of predictive assays can be defined: direct and indirect measurements of tumor cell survival and/or repair capability following irradiation and measurement of cellular and extracellular parameters affecting radiosensitivity. Examples from ongoing research at the University of Texas M. D. Anderson Hospital using one technique from each category (the micronucleus assay and flow cytometric analysis of tumor cell proliferation kinetics and ploidy) are used to illustrate potential methods of selecting patients for fast neutron radiotherapy.

We introduce spatial spillovers as an externality in the production function of competitive firms operating within a finite spatial domain under adjustment costs. Spillovers attenuate with distance and the overall externality could contain positive and negative components with the overall effect being positive. We show that when the spatial externality is not internalized by firms, spatial agglomerations may emerge endogenously in a competitive equilibrium. The result does not depend on increasing returns at the private or the social level and location advantages, but on the complementarity between capital and the spatial externality, existence of positive and negative local spillovers, and relatively large deviations between own and other-locations eff ects on the aggregate externality. No agglomerations emerge at the social optimum when spillovers are internalized and diminishing returns both from the private and the social point of view prevail. Numerical experiments with Cobb-Douglas technology and isoelastic demand confirm our theoretical predictions.

A simpli��ed energy balance climate model is considered with the global mean temperature as the state variable, and an endogenous ice line. The movements of the ice line towards the Poles are associated with damage reservoirs where initial damages are high and then eventually vanish as the ice caps vanish and the damage reservoir is exhausted. We couple this climate model with a simple economic growth model and we show that the endogenous ice line induces a nonlinearity. This nonlinearity when combined with two sources of damages - the conventional damages due to temperature increase and the reservoir damages - generates multiple steady states and Skiba points. It is shown that the policy ramp implied by this model calls for high mitigation now. Simulation results suggest that the policy ramp could be U-shaped instead of the monotonically increasing with low starting mitigation gradualist policy ramp.

We analyze endogenous pattern formation resulting from forward-looking optimizing behavior of economic agents in the presence of spatial spillovers modelled by continuous kernels. We use Fourier methods to identify nec- essary and su�¢ cient conditions for the emergence of optimal agglomeration through an optimal spillover induced instability of a spatially homogeneous steady state. We apply our methods to study the emergence of optimal ag- glomeration for a rational expectations equilibrium and an optimal growth model. We believe that our analytical methods can be used to systematically study optimal agglomeration and clustering in dynamic economics.