On the capacity of channels with block memory

The capacity of channels with block memory is investigated. It is shown that, when the problem is modeled as a game-theoretic problem, the optimum coding and noise distributions when block memory is permitted are independent from symbol to symbol within a block. Optimal jamming strategies are also independent from symbol to symbol within a block

Channels with block interference

A new class of channel models with memory is presented in order to study various kinds of interference phenomena. It is shown, among other things, that when all other parameters are held fixed, channel capacity C is an increasing function of the memory length, while the cutoff rate R0 generally is a decreasing function. Calculations with various explicit coding schemes indicate that C is better than R0 as a performance measure for these channel models. As a partial resolution of this C versus R0 paradox, the conjecture is offered that R0 is more properly a measure of coding delay rather than of coding complexity

FARM BUSINESS GOALS AND COMPETITIVE ADVANTAGE

This paper investigates empirically the relationship between both farm business goals and sources of competitive advantage, and various farm and producer characteristics using new primary data collected from a survey of Ohio farmers. Results show that most farmers do not recognize sources of competitive advantage and practice strategy implementation beyond reliance on longstanding paradigms for success within the context of government farm program support and the use of traditional risk management tools. However, several key insights emerge. Farmers who engage in cost leadership strategies are more profitable. Farmers who suggest that the goal of their farming operation is to enhance profitability/efficiency use more management tools, while lifestyle farmers use fewer. Larger farmers are more apt to engage in a cost leadership strategy, while those with higher debt-to-asset ratios and those that are more livestock oriented are more likely to engage in differentiation or focus strategies. Smaller farmers and those that produce specialty or value-added crops are more likely to focus on a particular niche market. Lastly, the use of the Internet as part of the farming operation does not influence the probability of engaging in any particular business strategy. It is apparent that the government farm program has contributed to a strategic where few producers have an explicit or implicit farm business strategy beyond "working the program" and acting as price takers. Or if a strategic choice is apparent, it rests primarily with cost leadership.Farm Management,

Software Engineering Laboratory Ada performance study: Results and implications

The SEL is an organization sponsored by NASA/GSFC to investigate the effectiveness of software engineering technologies applied to the development of applications software. The SEL was created in 1977 and has three organizational members: NASA/GSFC, Systems Development Branch; The University of Maryland, Computer Sciences Department; and Computer Sciences Corporation, Systems Development Operation. The goals of the SEL are as follows: (1) to understand the software development process in the GSFC environments; (2) to measure the effect of various methodologies, tools, and models on this process; and (3) to identify and then to apply successful development practices. The activities, findings, and recommendations of the SEL are recorded in the Software Engineering Laboratory Series, a continuing series of reports that include the Ada Performance Study Report. This paper describes the background of Ada in the Flight Dynamics Division (FDD), the objectives and scope of the Ada Performance Study, the measurement approach used, the performance tests performed, the major test results, and the implications for future FDD Ada development efforts

Gated rotation mechanism of site-specific recombination by ϕC31 integrase

Integrases, such as that of the Streptomyces temperate bacteriophage ϕC31, promote site-specific recombination between DNA sequences in the bacteriophage and bacterial genomes to integrate or excise the phage DNA. ϕC31 integrase belongs to the serine recombinase family, a large group of structurally related enzymes with diverse biological functions. It has been proposed that serine integrases use a “subunit rotation” mechanism to exchange DNA strands after double-strand DNA cleavage at the two recombining att sites, and that many rounds of subunit rotation can occur before the strands are religated. We have analyzed the mechanism of ϕC31 integrase-mediated recombination in a topologically constrained experimental system using hybrid “phes” recombination sites, each of which comprises a ϕC31 att site positioned adjacent to a regulatory sequence recognized by Tn3 resolvase. The topologies of reaction products from circular substrates containing two phes sites support a right-handed subunit rotation mechanism for catalysis of both integrative and excisive recombination. Strand exchange usually terminates after a single round of 180° rotation. However, multiple processive “360° rotation” rounds of strand exchange can be observed, if the recombining sites have nonidentical base pairs at their centers. We propose that a regulatory “gating” mechanism normally blocks multiple rounds of strand exchange and triggers product release after a single round

Effect of a new physiotherapy concept on bone mineral density, muscle force and gross motor function in children with bilateral cerebral palsy

Copyright @ 2010 The Authors.Objective: The purpose of this study was to determine the effect of a new physiotherapy concept on bone density, muscle force and motor function in bilateral spastic cerebral palsy children. Methods: In a retrospective data analysis 78 children were analysed. The concept included whole body vibration, physiotherapy, resistance training and treadmill training. The concept is structured in two in-patient stays and two periods of three months home-based vibration training. Outcome measures were dual-energy x-ray absorption (DXA), Leonardo Tilt Table and a modified Gross Motor Function Measure before and after six months of training. Results: Percent changes were highly significant for bone mineral density, -content, muscle mass and significant for angle of verticalisation, muscle force and modified Gross Motor Function Measure after six months training. Conclusions: The new physiotherapy concept had a significant effect on bone mineral density, muscle force and gross motor function in bilateral spastic cerebral palsy children. This implicates an amelioration in all International Classification of Functioning, Disability and Health levels. The study serves as a basis for future research on evidence based paediatric physiotherapy taking into account developmental implications

A Long and Winding Road: Federally Qualified Health Centers, Community Variation and Prospects Under Reform

Outlines growth in the number of, demand, and federal funding for FQHCs between 1997 and 2009 in twelve communities and factors that shape FQHC development, including variations in Medicaid eligibility rules, employer-sponsored coverage, and demographics

Study of low gravity propellant transfer Quarterly progress report, 23 Dec. 1970 - 30 Apr. 1971

Bellows, metallic diaphragm, and paddle vortex subcritical transfer systems designs and high pressure systems analyses for orbital space station cryogen

The relationship of the attributional dimensions of emotional differentiation on attributional dimensions of technology readiness for orthotic and prosthetic clinicians

Some individuals and groups seem to adopt emerging ideas and innovations more readily than others. Since any emerging innovation or technology inherently comes with a higher degree of uncertainty and risk, the group or individual must deal with the anxiety created by innovative behavior. Individuals who are less anxious and risk averse may tend to adopt innovations more easily than others. Within any social group, individuals can be classified into adopter categories based on their rate of adoption and capacity for risk and anxiety. Individuals who are more susceptible to anxiety in general, may seek the emotional scaffolding of their organizational group to support innovative behavior. This may be especially true in healthcare where contextual stress is heightened due to the emotional weight of decisions that greatly affect the well-being of others. Bowen Family Systems Theory has been used in family systems psychology to describe the systemic effects of group anxiety on the individual, an outcome referred to as differentiation. This study investigated if there was any relationship between emotional differentiation and technology readiness among allied health professionals. The Workplace Differentiation Inventory (WDI) and the Technology Readiness Index-2.0 (TRI-2.0) were the instruments used to measure both attributes. The statistical analysis explored the correlation and regression of the various sub-attributes of each measure as well as demographic attributes using a sample population derived from the orthotic and prosthetic allied healthcare profession