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We investigated the effect of ethanol on skeletal muscle development using C2C12 cell culture. The ethanol concentrations of 10 mM, 25 mM, and 100 mM, were tested because plasma samples of alcohol-dependent individuals fall within this range. We assessed two specific events in skeletal muscle development, the fusion of myoblasts to form myotubes and the acetylcholine receptor (AChR) clustering associated with neuromuscular synapse formation. We report that ethanol does not effect myotube formation or the viability of myoblasts or myotubes in C2C12 cell culture. However, ethanol does effect AChR clustering on C2C12 myotubes. As motor neurons approach skeletal muscle during development, agrin is released by motor neurons and induces AChR clustering on muscle fibers. In our experiments, agrin was applied to cell cultures during the period when myoblasts fuse to form myotubes. In cell cultures exposed to ethanol during myotube formation, agrin-induced AChR clustering was decreased compared to untreated cultures. In cell cultures exposed to ethanol during myoblast proliferation, with ethanol removed during myotube formation, agrin-induced AChR clustering was unaffected. We conclude that exposure to a physiologically relevant concentration of ethanol during the specific period of myotube formation decreases agrin-induced AChR clustering.

How has academic productivity changed in a decade in the American Academy of Pediatrics Section on Urology? Do academic pursuits slow as section members become older? What is the average number of publications yearly by section members? What percent of research is funded in pediatric urology? Has change occurred with multiple authorships?American Academy of Pediatrics Urology Section active memberships for 1993 and 2003 were obtained. A PubMed study was performed by reviewing all manuscripts published by American Academy of Pediatrics Section on Urology active members for 1991 to 1993 and 2001 to 2003. The data recorded were author, year, PubMed identification number, the number of authors, financial support and journal. Parametric and nonparametric statistics were used for analysis.In the 1991 to 1993 era there were 245 active members, of whom 145 published a total of 972 manuscripts. There were 604 clinical authorships, 161 basic science articles, 42 reviews and 186 case reports, of which 154 manuscripts received funding. In the 2001 to 2003 era there were 252 members, of whom 177 published a total of 1,152 manuscripts. There were 773 clinical authorships, 140 basic science articles, 107 reviews and 124 case reports, of which 151 manuscripts receiving funding. For members in the 2 periods the mean number of articles decreased by 1.0 from 1 decade to the next (p = 0.002).Scholarly pursuit of pediatric urology as a subspecialty has remained remarkably steady, averaging about 2 authorships per author yearly in the recent decade. The percent of authorships with funding in pediatric urology has decreased. The number of funded authorships has remained steady. A higher percent of American Academy of Pediatrics members have published manuscripts in the last decade. More manuscripts were published during the last decade study period than during the prior decade. The mix of manuscript types has changed with more reviews, and fewer case reports and basic science authorships in the most recent decade. New members are more likely to publish with a low unpublished percent.

The Apollo era was a remarkable time for manned spacecraft. In order to set our sights on once again leaving low earth orbit, it is a worthwhile exercise to take a look back at the engineering successes of Apollo, the overarching design philosophies behind the engineering and program decisions, and the lessons they learned that can be applied to current and future space programs. One project performed at The Johns Hopkins University's Chemical Propulsion Information Analysis Center (CPIAC) was to screen extensive amounts of design documentation and reports from multiple sources to identify, analyze, cross reference, and distill information on the underlying philosophy behind design decisions for the Apollo spacecraft's propulsion systems. This paper will highlight some of the key findings from that research, focusing on the design philosophies and factors that contributed to Apollo’s success. A discussion of the design philosophies and lessons learned from the design of Mercury, Gemini, and Apollo propulsion systems is provided. The lessons learned from Project Mercury were applied to the design of the Gemini systems. The purpose of the Gemini project was to provide direct support to the lunar effort by testing concepts and exploring system technologies for use in the Apollo program. Thus, the Apollo project represented an effort largely based on two successful manned spaceflight programs. The primary program approach factors and lessons learned from the Gemini and Mercury programs that contributed to the reliability and success of the Apollo design are discussed. The design philosophy and how each factor contributed to the success of the Apollo program is discussed. I. Introduction HE Mercury program had the goal of launching a man into space and returning him safely, with the side goal of seeing what a person would be capable of doing while in the space environment. At the time, it was unknown if the human body could even function in space, so the spacecraft’s re-entry control system was fully automated, with the manual system being secondary for experimental manned control purposes. The systems in the Mercury capsule (figure 1) were stacked one on top of the other within the capsule, not allowing for a component replacement or any other repair to be performed without having a direct affect on numerous other systems. The Gemini capsule (figure 2) was initially intended to be just a larger version of the Mercury capsule with some of the design problems corrected based on the lessons learned. But the Gemini’s program was meant to be used as a test of the requirements and capabilities that were needed to go to the Moon. Gemini mission requirements of testing the docking, rendezvous, and various other capabilities necessary for the Apollo program’s lunar mission required the addition of an orbit adjust and maneuvering system. The Gemini flight and experiment data was used for determining the requirements for Apollo systems. The lessons learned from the Mercury and Gemini programs were applied in principle to the Apollo spacecraft propulsion systems, as well to the Apollo program as a whole. This resulted in Apollo attaining the required reliability through design redundancy; extensive development, qualification, and acceptance testing; and stringent quality assurance for both development and production hardware.

The Johns Hopkins University, Chemical Propulsion Information Analysis Center (CPIAC) has been working closely with NASA Goddard Space Flight Center (GSFC); NASA Marshall Space Flight Center (MSFC); the University of Alabama at Huntsville (UAH); The Johns Hopkins University, Applied Physics Laboratory (APL); and NASA Jet Propulsion Laboratory (JPL) to capture satellite and spacecraft propulsion system information for an online database tool. The Spacecraft Chemical Propulsion Database (SCPD) is a new online central repository containing general and detailed system and component information on a variety of spacecraft propulsion systems. This paper only uses data that have been approved for public release with unlimited distribution. The data, supporting documentation, and ability to produce reports on demand, enable a researcher using SCPD to compare spacecraft easily, generate information for trade studies and mass estimates, and learn from the experiences of others through what has already been done. This paper outlines the layout and advantages of SCPD, including a simple example application with a few chemical propulsion systems from various NASA spacecraft.