On Cellular Algebras with Jucys Murphy Elements

We study analogues of Jucys-Murphy elements in cellular algebras arising from repeated Jones basic constructions. Examples include Brauer and BMW algebras and their cyclotomic analogues.Comment: Improved and reorganized exposition. Some new result

Cubic Polyhedra

A cubic polyhedron is a polyhedral surface whose edges are exactly all the edges of the cubic lattice. Every such polyhedron is a discrete minimal surface, and it appears that many (but not all) of them can be relaxed to smooth minimal surfaces (under an appropriate smoothing flow, keeping their symmetries). Here we give a complete classification of the cubic polyhedra. Among these are five new infinite uniform polyhedra and an uncountable collection of new infinite semi-regular polyhedra. We also consider the somewhat larger class of all discrete minimal surfaces in the cubic lattice.Comment: 18 pages, many figure

Psychographics on Steroids: The Attacks on Democratic Governments

Research originally developed in the 1970s to make television and mass media advertising more effective has involved into a contemporary system of propaganda manipulation. Agents use social media to convince people that fake news is a valid reason for people to act and to vote. While the Russian manipulation of the U.S. presidential election in 2016 has received the most attention, people are being manipulated around the world. These manipulations undermine democratic governments, which require an informed, voting public. This paper outlines the theories behind the manipulation of social media and the conditions under which these efforts are most likely to work

International Economic Agreements and the Constitution

International agreements, such as the General Agreement on Tariffs and Trade (GATT) and the North American Free Trade Agreement (NAFTA), generally aim to facilitate the free flow of goods and services among nations.1 The U.S. Supreme Court has developed a jurisprudence similarly aiming to facilitate the free flow of goods and services among the several states. That jurisprudence has developed from litigation challenging the constitutionality of state actions on the basis of the Commerce and Supremacy Clauses of the Constitution (art. I, § 8, cl. 3, and art. VI, cl. 2). In some subject areas, Commerce Clause decisions closely align with international agreements. In other areas, either or both fall short of achieving economic integration.

Rendezvous and Proximity Operations of the Space Shuttle

Space Shuttle rendezous missions presented unique challenges that were not fully recognized when the Shuttle was designed. Rendezvous targets could be passive (i.e., no lights or transponders), and not designed to facilitate Shuttle rendezvous, proximity operations and retrieval. Shuttle reaction control system jet plume impingement on target spacecraft presented induced dynamics, structural loading and contamination concerns. These issues, along with limited forward reaction control system propellant, drove a change from the Gemimi/Apollo coelliptic profile heritage to a stable orbit profile, and the development of new proximity operations techniques. Multiple scientific and on-orbit servicing missions and crew exchange, assembly and replinishment flights to Mir and to the International Space Station drove further profile and piloting technique changes, including new relative navigation sensors and new computer generated piloting cues

Space Shuttle Navigation in the GPS Era

The Space Shuttle navigation architecture was originally designed in the 1970s. A variety of on-board and ground based navigation sensors and computers are used during the ascent, orbit coast, rendezvous, (including proximity operations and docking) and entry flight phases. With the advent of GPS navigation and tightly coupled GPS/INS Units employing strapdown sensors, opportunities to improve and streamline the Shuttle navigation process are being pursued. These improvements can potentially result in increased safety, reliability, and cost savings in maintenance through the replacement of older technologies and elimination of ground support systems (such as Tactical Air Control and Navigation (TACAN), Microwave Landing System (MLS) and ground radar). Selection and missionization of "off the shelf" GPS and GPS/INS units pose a unique challenge since the units in question were not originally designed for the Space Shuttle application. Various options for integrating GPS and GPS/INS units with the existing orbiter avionics system were considered in light of budget constraints, software quality concerns, and schedule limitations. An overview of Shuttle navigation methodology from 1981 to the present is given, along with how GPS and GPS/INS technology will change, or not change, the way Space Shuttle navigation is performed in the 21 5 century

A Snake Trematode with an Unusual Condition of the Genital Atrium

On April 8, 1948, the writer collected a blue racer, Coluber constrictor ftaviventris Say, along a small creek about three miles south of Lacey-Keosauqua State Park, Van Buren County, Iowa. Upon examination, the mouth was found to contain two trematodes belonging to the subfamily Ochetosomatinae Leao, 1944 (= Reniferinae Pratt, 1902). The trematodes were fully mature adults and were identified as Ochetosoma. vallida (Nicoll, 1911). Nicoll originally described this species as Lechriorchis vallidus from the hognosed snake, Heterodon contortrix Linn., but it was transferred by Talbot ( 1933) to the genus Renifer Pratt because of the lateral position of the genital pore. Byrd and Denton (1938) included this species in their genus, Neorenijer Byrd and Denton, 1938. Kagan (1947) returned this species to the genus Renifer. Leao (1944) showed conclusively that Renifer Pratt, 1902 was a synonym of Ochetosoma Braun, 1901, both being originally described as parasites of the respiro-alimentary tracts of snakes

A Report on the Reptiles Collected by J. M. Shaffer From the Keokuk Area 1863-1895

On March 9, 1942, the Parsons College Biology Department undertook the identification of the J. M. Shaffer collection which had been on display at the Fairfield Public Library Museum for many years. The collection was found to contain many specimens without adequate collecting data. Each bottle had a number which corresponded with one kept in a ledger by Doctor Shaffer. Unfortunately through the years the ledger has been misplaced. All of the specimens in the collection fall within their established ranges with the exception of a single Phrynosoma cornutum. This specimen has only the date 1880 attached to the bottle. A population of this lizard in southern Iowa is extremely unlikely. As Keokuk is located in the extreme southeastern corner of the state it is impossible to determine whether all of the specimens were secured in Iowa, or if some were collected in either Missouri or in Illinois, just across the river

Delayed phlegmon with gallstone fragments masquerading as soft tissue sarcoma.

Complications from lost gallstones after cholecystectomy are rare but varied from simple perihepatic abscess to empyema and expectoration of gallstones. Gallstone complications have been reported in nearly every organ system, although reports of malignant masquerade of retained gallstones are few. We present the case of an 87-year-old woman with a flank soft tissue tumor 4 years after laparoscopic cholecystectomy. The initial clinical, radiographic and biopsy findings were consistent with soft tissue sarcoma (STS), but careful review of her case in multidisciplinary conference raised the suspicion for retained gallstones rather than STS. The patient was treated with incisional biopsy/drainage of the mass, and gallstones were retrieved. The patient recovered completely without an extensive resectional procedure, emphasizing the importance of multidisciplinary sarcoma care to optimize outcomes for potential sarcoma patients