Mechanical Properties Of Sediment Determine Burrowing Success And Influence Distribution Of Two Lugworm Species

We apply new perspectives on how organisms burrow by examining the association of in situ variation in sediment mechanical properties with burrowing ability and species distribution of two sympatric lugworms, Abarenicola pacifica and Abarenicola claparedi. We quantified the sediment\u27s resistance to penetration and its grain size distribution at sites inhabited by each species. Abarenicola pacifica individuals were found in significantly harder to penetrate, more heterogeneous sediments. We compared worm burrowing ability using reciprocal transplant experiments. Worms from firmer sediments, A. pacifica, were able to make successful steep burrows in sediments characteristic of either species. In contrast, A. claparedi individuals often failed to complete successful burrows in the firmer A. pacifica sediment. To examine how morphological differences could explain these patterns, we compared body wall musculature and measured how well individuals support their own bodies when draped over a cantilever. Lugworms from the firmer sediment had thicker body wall musculature and held their bodies more rigidly than did worms from softer sediments. Additionally, we observed subtle differences in the papillae on the proboscises\u27 surfaces, which could affect worm–sediment interactions, but we found no differences in the chaetae of the two species. Abarenicola claparedi produced more mucus, which could be important in shoring up burrow walls in their shifting, sandy habitat. This study presents the first example of using field-based experiments to determine how sediment mechanical properties and worm burrowing ability could act to determine organismal distribution. Our findings have broader ecological implications because of the role of lugworms as ecosystem engineers

Development of high energy density primary batteries Fourth quarterly report, 22 Mar. - 21 Jun. 1966

High energy density primary batteries for space flight applications - electrolyte systems, cell systems, and positive electrode constructio

Conscience of a Catholic Judge

Symposium theme — Evolving Standards of Decency in 2003: Is the Death Penalty on Life Support

The Meaninglessness of the Plain Meaning Rule

The contemporary lawyer and judge confront, in the mine run of their daily work, a mountain of statutes. In an unprecedented way, law today is statute law, and few legal problems have escaped the tender mercies of the legislature. Statutory interpretation is a daily and pressing task for virtually every lawyer. And yet, there is no generally accepted consistent theory to guide this work. The late Henry Hart and Dean Albert Sacks argue forcefully, [T]he hard truth of the matter is that American courts have no intelligible, generally\u27 accepted, and consistently applied theory of statutory interpretation. \u27 This conclusion is embedded in several hundred pages of case excerpts proving the point beyond dispute. Good legal theory is not an intellectual luxury. If we lack good theory, we will be unable to explain judicial decisions and consumers of the output of our court systems will not believe they have been justly treated. Without the discipline of good theory, we cannot even critique and reform our own work product as lawyers. My thesis in this article is that the so-called plain meaning rule is not only wrong in itself, but is also a major stumbling block hindering the adoption of a sound theory of statutory interpretation. Legal thinking in terms of the rule, whether to follow it or to find an exception, structures our whole approach to statutory interpretation; its repudiation is a present necessity. I wish in this article to summarize criticisms of the plain meaning rule, suggest why it has survived despite criticism, and sketch a theory and practice of statutory interpretation which should replace it

Review: Powdery Scab of Potato—Increased Knowledge of Pathogen Biology and Disease Epidemiology for Effective Disease Management

The importance of the potato tuber disease powdery scab, caused by the zoosporic pathogen Spongospora subterranea f. sp. subterranea, has increased worldwide, and the disease is one of the most important problems facing potato production in some regions. This soilborne pathogen produces many resting spores which can remain dormant for long periods, are highly resistant to environmental stresses and can spread the disease on seed potatoes and in contaminated soil. The enigmatic nature of this organism exacerbates the development of effective powdery scab control methods. Substantial knowledge has been gained in the last decade on the biology of the pathogen and the epidemiology of the disease, but no single effective control measure is, or is likely to be, available. An integrated approach to powdery scab management is the aim, with host resistance as a substantial and sustainable component. Further research on the epidemiology of powdery scab and population genetics of the pathogen is urgently required. All stakeholders involved in the potato industry must become aware that solution of the powdery scab problem is likely to be a long-term goal. When resistant cultivars with all the other characteristics demanded for marketing high-quality potatoes are available, and when disease risk from the pathogen on seed and/or in soil can be accurately determined, then the mission to develop effective powdery scab control will become achievabl

Multi-agent system for dynamic manufacturing system optimization

This paper deals with the application of multi-agent system concept for optimization of dynamic uncertain process. These problems are known to have a computationally demanding objective function, which could turn to be infeasible when large problems are considered. Therefore, fast approximations to the objective function are required. This paper employs bundle of intelligent systems algorithms tied together in a multi-agent system. In order to demonstrate the system, a metal reheat furnace scheduling problem is adopted for highly demanded optimization problem. The proposed multi-agent approach has been evaluated for different settings of the reheat furnace scheduling problem. Particle Swarm Optimization, Genetic Algorithm with different classic and advanced versions: GA with chromosome differentiation, Age GA, and Sexual GA, and finally a Mimetic GA, which is based on combining the GA as a global optimizer and the PSO as a local optimizer. Experimentation has been performed to validate the multi-agent system on the reheat furnace scheduling problem

A comparison of regionalisation methods for catchment model parameters

International audienceIn this study we examine the relative performance of a range of methods for transposing catchment model parameters to ungauged catchments. We calibrate 11 parameters of a semi-distributed conceptual rainfall-runoff model to daily runoff and snow cover data of 320 Austrian catchments in the period 1987-1997 and verify the model for the period 1976-1986. We evaluate the predictive accuracy of the regionalisation methods by jack-knife cross-validation against daily runoff and snow cover data. The results indicate that two methods perform best. The first is a kriging approach where the model parameters are regionalised independently from each other based on their spatial correlation. The second is a similarity approach where the complete set of model parameters is transposed from a donor catchment that is most similar in terms of its physiographic attributes (mean catchment elevation, stream network density, lake index, areal proportion of porous aquifers, land use, soils and geology). For the calibration period, the median Nash-Sutcliffe model efficiency ME of daily runoff is 0.67 for both methods as compared to ME=0.72 for the at-site simulations. For the verification period, the corresponding efficiencies are 0.62 and 0.66. All regionalisation methods perform similar in terms of simulating snow cover

The prevalence of patent interferences in gene technology

Unlike all other countries in the world, the United States awards patents to the first to invent, not to the first to file an application for a patent. In cases where two or more inventors submit patent applications claiming the same invention, an interference may be declared. Interference is the process by which the US Patent & Trademark Office (USPTO; Washington, DC, USA) determines which of the applicants was the first to invent and diligently reduce the invention to practice. More than half of these are resolved in favor of the inventor who was the first-to-file, raising questions about whether this unique system is worth retaining. Interferences are relatively rare. For the period 1998-2002, an average of four interferences were declared for every 10,000 patent applications filed. Data we have gathered suggest that interference proceedings in gene discovery and biotechnology are much more prevalent than other areas of technology. The resulting legal fees are costing the biotechnology industry millions of dollars each year