Ethical principles and the revision of organic rules

Strong ethical principles are seen as a tool to evaluating the development of organic agriculture so that corrections can be made where they are considered necessary. This report explains how the EU project, Organic Revision, is expected to do just that

Topological Characterization of Consensus Solvability in Directed Dynamic Networks

Consensus is one of the most fundamental problems in distributed computing. This paper studies the consensus problem in a synchronous dynamic directed network, in which communication is controlled by an oblivious message adversary. The question when consensus is possible in this model has already been studied thoroughly in the literature from a combinatorial perspective, and is known to be challenging. This paper presents a topological perspective on consensus solvability under oblivious message adversaries, which provides interesting new insights. Our main contribution is a topological characterization of consensus solvability, which also leads to explicit decision procedures. Our approach is based on the novel notion of a communication pseudosphere, which can be seen as the message-passing analog of the well-known standard chromatic subdivision for wait-free shared memory systems. We further push the elegance and expressiveness of the "geometric" reasoning enabled by the topological approach by dealing with uninterpreted complexes, which considerably reduce the size of the protocol complex, and by labeling facets with information flow arrows, which give an intuitive meaning to the implicit epistemic status of the faces in a protocol complex

The Time Complexity of Consensus Under Oblivious Message Adversaries

We study the problem of solving consensus in synchronous directed dynamic networks, in which communication is controlled by an oblivious message adversary that picks the communication graph to be used in a round from a fixed set of graphs ? arbitrarily. In this fundamental model, determining consensus solvability and designing efficient consensus algorithms is surprisingly difficult. Enabled by a decision procedure that is derived from a well-established previous consensus solvability characterization for a given set ?, we study, for the first time, the time complexity of solving consensus in this model: We provide both upper and lower bounds for this time complexity, and also relate it to the number of iterations required by the decision procedure. Among other results, we find that reaching consensus under an oblivious message adversary can take exponentially longer than both deciding consensus solvability and broadcasting the input value of some unknown process to all other processes

Balancing and integrating basic values in the development of organic regulations and standards: proposal for a procedure using case studies of conflicting areas

The basic aim of the report is to develop a procedure for the integration of the ethical value base of organic farming into standards and regulations. For this it is necessary to identify the core ethical value of organic production, consider their coherence and relate them to existing practice of organic food and farming. Ethical values are per se in need of interpretation. It is therefore also necessary to consider the process of decision-making, when aiming to achieve a coherent integration of such values in the structure of a standard or regulation. In line with the European Action Plan for organic food and farming from 2004 the Project EEC 2092/91 (Organic) Revision supports the idea that delegating a larger role to values and basic principles will help to harmonise the rules, provide room for flexibility in implementation and to simplify the European Regulation for organic production. It is important to include basic values in standards and regulations, because organic farming is value based and all actors/stakeholders have value expectations, including consumers who the regulation wants to protect. Standards and regulations form the basis of a virtual contract between the consumer and the producers. By following the practices set out in the standards, producers give a promise to the consumer to deliver on additional ethical values, beyond the legal minimum standards for conventional agriculture and food. The growing and globalised organic market and the involvement of large companies have resulted in renewed interest in the values and principles of organic farming. There has been concern that the organic food and farming sector is becoming more conventionalised, and has lost touch with its basic values. Thus it will no longer function effectively as a real alternative to general agriculture for consumers, producers and also for policy makers. The report analyses what core ethical value are associated with organic agriculture and should therefore be considered for inclusion in a regulation. This value base is contrasted with the existing Regulation (EEC) 2092/91 and with examples of current practice of organic agriculture in Europe. The implications of including ethical values in the structure of a regulation for decisionmaking are considered. Following on from the European Action Plan a process of total revision of the EU regulation on organic production is underway. A new European Regulation for organic production was adopted by the European Council of Ministers in June 2006 and will come into force in Jan 2009. The text of the near final proposal from December 2006 has been considered in several sections of the report. The report finishes with some conclusions and recommendations for the EU Commission and other standard setting bodies regarding the choice and roles of values in organic standard, the rules for decision-making processes in relation to integrating values, and regarding the ongoing revision of the organic regulation in Europe

Continuous Tasks and the Asynchronous Computability Theorem

The celebrated 1999 Asynchronous Computability Theorem (ACT) of Herlihy and Shavit characterized distributed tasks that are wait-free solvable and uncovered deep connections with combinatorial topology. We provide an alternative characterization of those tasks by means of the novel concept of continuous tasks, which have an input/output specification that is a continuous function between the geometric realizations of the input and output complex: We state and prove a precise characterization theorem (CACT) for wait-free solvable tasks in terms of continuous tasks. Its proof utilizes a novel chromatic version of a foundational result in algebraic topology, the simplicial approximation theorem, which is also proved in this paper. Apart from the alternative proof of the ACT implied by our CACT, we also demonstrate that continuous tasks have an expressive power that goes beyond classic task specifications, and hence open up a promising venue for future research: For the well-known approximate agreement task, we show that one can easily encode the desired proportion of the occurrence of specific outputs, namely, exact agreement, in the continuous task specification

Predictors of readmission and health related quality of life in patients with chronic heart failure: a comparison of different psychosocial aspects

Psychological distress is common in patients with chronic heart failure. The impact of different psychological variables on prognosis has been shown but the comparative effects of these variables remain unclear. This study examines the impact of depression, anxiety, vital exhaustion, Type D personality, and social support on prognosis in chronic heart failure patients. One hundred eleven patients (mean age 57±14years) having participated in an exercise based ambulatory cardiac rehabilitation program were enrolled in a prospective cohort study. Psychological baseline data were assessed at program entry. Mortality, readmission, and health-related quality of life were assessed at follow up (mean 2.8±1.1years). After controlling for disease severity none of the psychological variables were associated with mortality, though severe anxiety predicted readmission [HR=3.21 (95% CI, 1.04-9.93; P=.042)]. Health-related quality of life was independently explained by vital exhaustion, anxiety and either body mass index (physical dimension) or sex (emotional dimension). As psychological variables have a strong impact on health-related quality of life they should be routinely assessed in chronic heart failure patients's treatmen

Association Between Posttraumatic Stress Disorder Following Myocardial Infarction and Liver Enzyme Levels: A Prospective Study

Background: Research in rodents demonstrated that psychological stress increases circulating levels of alanine transaminase, aspartate transaminase, and alkaline phosphatase reflecting liver injury. Moreover, chronic posttraumatic stress disorder and transaminases predicted coronary heart disease. Aims: To investigate the hypothesis that severity of posttraumatic stress disorder following myocardial infarction would prospectively relate to liver enzymes. Methods: Study participants were 24 patients (mean 59±7years, 79% men) with an interviewer-rated diagnosis of posttraumatic stress disorder caused by an index myocardial infarction 3±3months before. After a mean follow-up of 26±6months, patients had a clinical interview to reassess posttraumatic stress disorder severity, a medical history, and blood collected to determine liver enzymes. Results: Total posttraumatic stress disorder symptoms assessed at study entry prospectively predicted plasma levels of alanine transaminase (r=.47, p=.031) and alkaline phosphatase (r=.57, p=.004), but not of aspartate transaminase (p=.15), controlling for follow-up duration and antidepressant use. Total posttraumatic stress disorder symptoms assessed at follow-up were associated with alanine transaminase (r=.72, p=.004), aspartate transaminase (r=.60, p=.018), and alkaline phosphatase (r=.64, p=.001) in the 16 patients who had maintained diagnostic posttraumatic stress disorder, but not in all 24 patients. Conclusions: The severity of posttraumatic stress disorder following myocardial infarction was associated with mild increase in liver enzyme levels, suggesting that chronic psychological stress relates to hepatic damage in humans. This might help to explain the previously observed increased cardiovascular risk in chronically traumatized individual