The synthesis of some acylglycines and related oxazolones

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The Fishing Ports of Maine and New Hampshire: 1978, Report to the National Science Foundation, Volume I

This volume is part of a final report on social science aspects of fisheries management in New England and is divided into three sections. In Section I, general background information is given concerning aspects of the fisheries in northern New England. Included is a history of fishing in the area, general information on the coastal environment and biology of major species caught and a background on fishing boats and gear, marketing and processing, and the legal environment. Section II describes each of the ports in Maine and New Hampshire, as they were in the baseline year of 1978, outlining the physical setting and population, the major industries, general infrastructure, and port infrastructure. Section III describes the local variations in the fishing industry of northern New England. This is done, in the maine, by presenting a statistical summary of the information contained in the port descriptions. (Sinha - OEIS

Biological and Economic Effects of Increasing the Minimum Legal Size of American Lobster in Maine

The Northeast Marine Fisheries Board recently completed a comprehensive management plan for American lobster Homarus americanus, the most important provision of which is to raise the legal minimum size of lobsters from 81 to 88.9 mm carapace length incrementally over 5 years. Its objective is to increase egg production and recruitment, and thus reduce the likelihood of stock failure; economic benefits are anticipated for fishermen. However, a model used to analyze the frequency distributions of some 9,000 Maine lobsters demonstrates that in every year the legal minimum size is increased, smaller numbers and less weight of lobsters would be landed than at present. After the legal measure reaches 88.9 mm, there most likely still would be fewer lobsters harvested, but a 7.9% increase in landed weight due to increases in yield/recruit. An economic analysis by two-stage least-squares regression demonstrates that these changes in catches would result in a loss in total revenue to the Maine lobster industry in all 5 years the legal measure is increased. After it has reached 88.9 mm, total revenue to lobster fishermen most likely would be 5.5% higher than it is now, a 13% internal rate of return on investment. These results suggest that increasing the legal lobster measure is problematic from the point of view of those in the industry

Liquid drop splashing on smooth, rough and textured surfaces

Splashing occurs when a liquid drop hits a dry solid surface at high velocity. This paper reports experimental studies of how the splash depends on the roughness and the texture of the surfaces as well as the viscosity of the liquid. For smooth surfaces, there is a "corona" splash caused by the presence of air surrounding the drop. There are several regimes that occur as the velocity and liquid viscosity are varied. There is also a "prompt" splash that depends on the roughness and texture of the surfaces. A measurement of the size distribution of the ejected droplets is sensitive to the surface roughness. For a textured surface in which pillars are arranged in a square lattice, experiment shows that the splashing has a four-fold symmetry. The splash occurs predominantly along the diagonal directions. In this geometry, two factors affect splashing the most: the pillar height and spacing between pillars.Comment: 9 pages, 11 figure

An Evaluation of Web Browsers

Many computational biologists would agree that, had it not been for multi-processors, the construction of multi- processors might never have occurred. In this position paper, we argue the exploration of interrupts. We present a novel heuristic for the visualization of Scheme, which we call YAWN

Model studies of metal-slag reactions in reaction generated foams.

A room temperature model lias been developed which simulates certain aspects of the slag-raetal-gas reactions that occur in L.3). steelmaking. In the model the molten iron was represented by a pool of sodium amalgam, the slag by a mixture of water and glycerol and the oxygen by a hydrogen chloride-nitrogen jet. Droplets of amalgam ejected from the bath by the impinging gas jet, reacted with the hydrogen chloride dissolved in the model slag to produce bubbles, thus forming a dynamic foam. To gain more information about the fundamental refining processes in the model, the behaviour of single droplets of amalgam in acid media has been studied. When the sodium content of individual droplets was high, the rate of reaction was controlled by the discharge of hydrogen ions at the reaction interface, with rate dependence on the hydrogen ion concentration in the aqueous phase. This is analogous to decarburisation rate control by transport of oxygen ions in the slag phase.Under hydrogen ion discharge control, the refining rate in the model converter initially increased but eventually attained an approximately steady value. The level of this rate plateau was shown to be strongly influenced by the rate of transfer of hydrogen chloride from the jet gases to the slag phase. Similarly in oxygen steelmaking the decarburisation rate plateau has been shown to be determined mainly by the oxygen blowing rate. The model converter has been used to qualitatively investigate the effect of lance height, jet momentum and mass flow rate of gaseous reactant into the reaction vessel on the mean plateau refining rate. The results obtained compare favourably with analogous variables in steelmaking practice. In addition the effect on the refining rate of pressurising the reaction vessel has also been investigated. An improvement in refining rate was achieved, partly due to improved slag-metal drop contact and partly to increased hydrogen chloride flow rate. It is not believed that such asignificant improvement would be achieved for steelmaking conditions although there might be some advantage derived from improved control over slopping at high oxygen flow rates. When the sodium content of single amalgam droplets fell below a critical level, determined by the acid concentration in the aqueous phase, the rate of reaction became controlled by sodium transport to the reaction interface. This is analogous to decarburisation rate control by carbon transport within iron droplets. In both the model converter and in steelmaking this gives rise to a progressively decreasing refining rate

Sleep disturbance at pre-deployment is a significant predictor of post-deployment re-experiencing symptoms.

Background: Insomnia is common in service members and associated with many mental and physical health problems. Recently, longitudinal data have been used to assess the impact of disturbed sleep on mental health outcomes. These studies have consistently shown relationships between sleep disturbance and development of mental illness. Objective: The present study examined the longitudinal relationship between sleep disturbance and PTSD symptomatology in a cohort of Marines and Navy Corpsmen deployed to Iraq and Afghanistan (n = 2,404) assessed prior to deployment, as well as at -3 and 6 months post-deployment. Additionally, we aimed to investigate the extent to which these relationships are moderated by combat-stress severity, and to what extent these findings are replicated in a second, separate cohort of Marines and Navy corpsmen (n = 938) assessed with identical measures prior to deployment and within 3 months of return. Method: The present study employed latent variable path models to examine the relationships between pre-deployment sleep disturbance and post-deployment re-experiencing symptoms. Initial cross-lagged path models were conducted on discovery and replication samples to validate the hypothesized predictive relationships. Follow up moderation path models were then conducted to include the effect of combat-stress severity on these relationships. Results: Initial cross-lagged models supported a significant relationship between pre-deployment sleep disturbance and future re-experiencing PTSD symptoms at all time points. Initial moderation models showed a small moderator effect of combat-stress severity, though the main predictive relationship between pre-deployment sleep disturbance and PTSD symptoms remained significant. The moderator effect was not significant in the replication sample. Conclusions: The results of this study support pre-deployment sleep disturbance as a risk factor for development of post-deployment PTSD symptoms. Interventions aimed at normalizing sleep may be important in preventive measures for PTSD

CNH: Fine-Scale Dynamics of Human Adaptation in Coupled Natural and Social Systems: An Integrated Computational Approach Applied to Three Fisheries

The purpose of this project is to gain a better understanding of the way competition between individual fishermen lead to the emergence of private incentives and informal social arrangements that are (or are not) consistent with conservation of the resource. These informal arrangements and incentives are important because they help us understand the extent to which private interests might strengthen or weaken on-going resource management and, consequently, the sustainability of coupled human and natural systems. The broad hypothesis driving the study is that the informal social structure that emerges from competitive interactions among fishermen reflects the particular circumstances of the natural system. In some cases, successful competition requires secretive non-cooperative behavior; in others, cooperation tends to yield better competitive results. These different outcomes have different, and not always obvious, impacts on the feasibility and effectiveness of resource management. We think of the relevant human social process as one in which individuals compete with one another through time-consuming and costly acquisition of valuable knowledge about a complex resource. To compete successfully, individuals must balance the immediate benefits that come from exploiting knowledge they currently hold with the costly need to explore for new knowledge; additionally, when seeking new knowledge, individuals must balance the costs and benefits of acquiring knowledge through cooperation or through autonomous search. In order to model this kind of competitive process, we employ a significantly modified version of a technique borrowed from computer science called a learning classifier system (LCS). LCS uses a genetic algorithm to mimic the way an agent (here a fisherman) uses his experience to continuously refine his knowledge and decisions about his natural and social environment. The importance of LCS is that it permits simulation of the co-evolving strategic interactions of self-interested fishermen who are only partially informed about the state of the resource they are exploiting and the fishermen with whom they compete. The problem of understanding these kinds of competitive dynamics is evident in almost all coupled natural and human systems. We apply the approach to a comparative study of three Gulf of Maine fisheries which are characterized by significantly different temporal and spatial dynamics - sea urchins, lobster and cod. Each fishery will be modeled using a biophysical simulator of the natural system and a tightly integrated multi-agent learning classifier system that simulates the learning and interactions of fishermen. The design of each model will be based in part on extensive interviews with fishermen about their knowledge of the dynamics of the fisheries in which they work. We will use these models to explore past and prospective policy problems in each fishery. Beyond the immediate applicability of these explorations, we expect this project will provide a foundation for the wider use of multi-agent learning models in other coupled systems. Project outcomes will be transmitted regularly to industry and managers. Principal investigators include economists, biologists, anthropologists and computer scientists. All the PIs have years of experience in the fisheries of the Gulf of Maine and have well developed relationships with individual fishermen and managers. A masters level student in marine policy, a Ph.D. student in computer or marine science and a post-doctoral researcher in computer science will be employed on the project. In addition, the project will develop an undergraduate course in complex adaptive social-ecological systems and a graduate student/faculty workshop in the same area