Some Predators of Polyps of Chrysaora quinquecirrha (Scyphozoa, Semaeostomeae) in the Chesapeake Bay

Some invertebrate predators of polyps of Chrysaora quinquecirrha were identified. They included Caprella equilibra, Callipallene brevirostris, N eopanope texana sayi, Pagurus longicarpus, Libinia dubia, and Cratena pilata. Only C. pilata showed a preference over other possible prey organisms

Summary of the effects of Agnes on oyster setting in Virginia in 1972

Oyster setting in Virginia River systems dropped to the lowest level on record during 1972. Spatfall studies indicate this poor condition to be the direct result of the effects of tropical storm Agnes

Chesapeake Oyster Reefs, Their Importance, Destruction and Guidelines for Restoring Them

The eastern oyster, Crassostrea virginica (Gmelin), can live any place in coastal marine and estuarine waters of the North American east coast offering suitable setting and survival opportunities. It occurs singly or in small clumps scattered widely but thrives best in colonial aggregations which, like those of tropical corals, are truly reefs. The massive self-renewing oyster reefs ( whole banks and beds ) reported by early Chesapeake observers have yielded much. Without readily accessible oyster reefs the first English colonists of Jamestown might have starved. Without them the rich oyster industries of later years could never have developed.But oyster reefs benefitted the oysters that built and maintained them as well as the humans using them. The oyster reefs of the Chesapeake region, including those on Seaside, developed during some 7,000-6,000 years of Bay evolution during the current (Holocene) Epoch. Until about 200 years ago reef oyster populations were able to maintain themselves and their reef habitats and withstand the inroads of biological enemies, other natural hazards and increasing harvests. By the late 1800s, Chesapeake public market oyster harvests had peaked and total market harvests and the oyster populations which provided them were in decline. more ...https://scholarworks.wm.edu/vimsbooks/1091/thumbnail.jp

Clarity, Organization, Precision, Economy: A Technical Writing Guide for Engineers

Faculty and employers who work with engineers have consistently identified four areas of deficiency in the engineers’ technical writing: clarity, organization, precision and economy. This third edition of the guidebook grew out of efforts to teach engineering students at the University of New Haven to improve their communication skills. David Adams lays out fourteen guidelines and numerous examples that students and faculty can use as common ground when discussing writing.https://digitalcommons.newhaven.edu/civilengineering-books/1000/thumbnail.jp

Rehabilitation Of The Troubled Oyster Industry Of The Lower Chesapeake Bay

After 1885 Virginia\u27s lower Chesapeake Bay system produced more oysters per year than any other area in the United States and remained predominant until 1960. Since then she has surrendered supremacy as annual harvests of her troubled oyster industry have steadily declined. Numerous factors were responsible for the tremendous productivity of the lower Bay\u27s oyster beds; a number have been involved in its decline. Natural events, such as the catastrophic epizootics of the early 1960\u27s, continuing disease and predation, increased salinities of drought years and great freshets of tropical storms have contributed significantly to the reduction. Pollution and other man-related alterations have been involved also. Additionally, high costs of money and operations, risk-reduction efforts, loss of competitive position and markets, and, in some problem areas, lack of certain important scientific knowledge have contributed. Persistent overfishing by public harvesters, lack of application of best-management practices and recent technological advances, reduction of planting efforts by private growers, and resistance to remedial improvements by industry and public managers are the major factors causing the continuing decline! Nevertheless, restoration of oyster production in Virginia (and Maryland) waters can be accomplished by applying a combination of currently available scientific knowledge and technological skills and by making or enabling sociological, economic and political improvements

Comparative attachment, growth and mortalities of oyster (Crassostrea virginica) spat on slate and oyster shell in the James River, Virginia

Slate was investigated as a substitute for oyster shells which are used as a substrate for oyster spat (Crassostrea virginica) settlement in James River, Virginia oyster repletion programs. Oyster shells and slate fragments were planted on adjacent plots in two submerged locations about 825 m apart in July 1984. Quantitative .093 m2 (one ft2) samples were collected by a diver on seven occasions through July 1985, with additional samples collected from teh natural oyster bottoms adjacent to the two areas. Percent mortality, growth and numbers of live spat and spat scars (dead spat) per unit area of bottom were determined. As the end of the study, the number of spat on shell was 4-5 times higher than on slate; however, slate had 5-6 times more spat per unit area of bottom than the shell on the natural bottom. During the July to October setting season mortalities were much higher on slate than on shell; during the remaining period they were high but about equal on both substances

The Effect of Tropical Storm Agnes on Oysters, Hard Clams, Soft Clams, and Oyster Drills in VIrginia

Tropical Storm Agnes had a major effect on the molluscan fisheries of Virginia. One effect was the direct mortality of oysters, Crassostrea virginiaa, in the upper parts of many estuaries. Typical losses on leased bottoms were: the James River, 10%; the York River, 2%; the Rappahannock River, 50%; and the Potomac River tributaries (Virginia) 70%. Economic loss was in excess of 7.9 million dollars. There was a nearly complete absence of oyster larvae attachment (setting) in 1972. Other effects of Agnes included a nearly complete loss of soft clams, Mya arenaria, in the Rappahannock River. Hard clams, Meraenaria meraenaria, were killed in the upper part of the York River. Oyster drills, Urosalpinx ainerea, were eliminated from the Rappahannock and reduced greatly in numbers in the York and James Rivers.https://scholarworks.wm.edu/vimsbooks/1074/thumbnail.jp

Automated proof checking in introductory discrete mathematics classes

Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (page 61).Mathematical rigor is an essential concept to learn in the study of computer science. In the process of learning to write math proofs, instructors are heavily involved in giving feedback about correct and incorrect proofs. Computerized feedback in this area can ease the burden on instructors and help students learn more efficiently. Several software packages exist that can verify proofs written in specific programming languages; these tools have support for some basic topics that undergraduates learn, but not all. In this thesis, we develop libraries and proof automation for introductory combinatorics and probability concepts using Coq, an interactive theorem proving language.by Andrew J. Haven.M. Eng