Leg-extension strength and chair-rise performance in elderly women with Parkinson's disease

The lower extremity performance in elderly female patients with mild to moderate Parkinson's disease (PD; n = 12) and controls (n = 16) was compared. Isometric dynamometry and force-plate measurements were used. PD patients had lower (p < .05) bilateral (BL) maximal isometric leg-extension force (MF), BL isometric MF relative to body mass, and maximal rate of isometric force development than control participants. BL strength deficit was greater (p < .05) in PD patients than in controls. A significantly longer chair-rise time and lower maximal rate of vertical-ground-reaction-force development while rising from a chair was found in PD patients than in controls. These findings suggest that elderly women with PD have lowered voluntary isometric force-generation capacity of the leg-extensor muscles. Reduced BL leg-extension strength might contribute to the difficulty of individuals with PD to rise from a chair.     

Neurophysiology and freedom of the will

In the first two sections of the paper, some basic terminological distinctions regarding freedom of the will as a philosophical problem are expounded and discussed. On this basis, the third section focuses on the examination of two neurophysiological experiments (one by Benjamin Libet and one by William Grey Walter), which in recent times are often interpreted as providing an empirical vindication of determinism and, accordingly, a refutation of positions maintaining freedom of the will. It will be argued that both experiments fall short in this respect, and that in general—for methodical reasons—the prospects of ever deciding the dispute about freedom of the will through empirical research are rather poor.

---

Zusammenfassung  In den ersten beiden Teilen dieses Beitrags werden einige grundlegende terminologische Unterscheidungen bezüglich Willensfreiheit als philosophisches Problem erläutert und diskutiert. Auf dieser Grundlage befasst sich der dritte Teil mit der Untersuchung zweier neurophysiologischer Experimente (eines von Benjamin Libet, das andere von William Grey Walter), die in jüngerer Zeit gern als empirische Bestätigung des Determinismus und damit als Widerlegung von Positionen interpretiert werden, die eine Freiheit des Willens behaupten. Wir argumentieren, dass beide Experimente in dieser Hinsicht mangelhaft sind und dass allgemein die Aussichten, den Disput über Willensfreiheit durch empirische Forschung zu lösen, aus methodischen Gründen eher gering sind.

---

Résumé  Les deux premières sections de larticle exposent et discutent certaines distinctions terminologiques concernant le « libre arbitre » en tant que problème philosophique. Sur cette base, la troisième section se concentre sur lexamen de deux expériences neurophysiologiques (lune par Benjamin Libet et lautre par William Grey Walter), souvent interprétées ces derniers temps comme fournissant une justification au déterminisme et, par conséquent, une réfutation des positions affirmant la liberté de la volonté. Largumentation fait ressortir que les deux expériences ne parviennent pas à leur but à cet égard et que de façon générale, pour des raisons méthodologiques, les perspectives de trancher la question du libre arbitre par la recherche empirique sont plutôt mauvaises.

---

Achtsamkeit lernen im Offenen Dialog

Dialogue in the sense of David Bohm invites individuals and groups to consider together their ways of thinking and learning. By exploring mental models, which usually hinder reaching deeper agreement, this kind of dialogue opens new grounds and is, at the latest, since Peter Senge’;s management-bestseller “The fifth discipline” (1990), considered to be a basic process for team learning in groups and organisations. The article refers to university projects on ‘open dialogue’ with students at the universities of Oldenburg and Bochum between 2001–2003. Characteristics of “open dialogue” are represented as ways of attentiveness learning. Students practical reports are used to work out recommendations based upon “open dialogue” for the development of central deep ecology and human competences.     

Anmerkungen zum Thema Nachfolge und Organisationswandel

I personally understand succession processes as an interface of organization evolutions. The way in which these are settled indicates the development direction of the organization as a conservative or a progressive one. The following will discuss organization changes regarding fluidity and virtuality.The limits of such an organization are more and more psychological, the management personality has a big influence regarding the chances related to changes.In how far, at the leadership level, the deviation readiness can be established through arranged successors, essentially determines the organization’s chance to adjust to changing environmental conditions.     

Besser entscheiden im Team — aber wie?

Investment committees of banks, pension funds or investment clubs meet regularly. The members decide together about the allocation and the timing of their own assets or their customers assets. This article will point out some pitfalls and chances that are typical in this decision making process. Especial focus is set on financial psychological aspects with regards to information processing and decision making processes. At the end of the article the author will indicate a sustainable way to improve the quality of team decisions.     

Können Organisationen nicht lernen? Facetten organisationaler Lernkulturen

Recently, the concept of ‘learning culture’ has entered the discussion on learning organizations and organizational learning, especially in the German speaking countries. Most of the academics, but also practitioners seem to use the term ‘learning culture’ in a particular sense as nurturing a self-directed, on-the-job learning of all employees. An implicit, often neglected assumption of this conception is that organizations can be divided into those who have a learning culture and those who do not. Although this idea of a dichotomy is also found in the discussion on learning organizations, it can be called into question. Past research has shown that (organizational) learning is a multifaceted phenomenon. Different organizations engage in very diverse kinds of learning due to the fact that they are facing varying environmental conditions. This brings us to doubt the idea of a ?one-best-way“ learning culture. Following the basic question, who learns what, how, when and why, the article presents a set of distinguishing attributes to distinguish between different types of learning cultures. Finally, yet unanswered questions and paths for future research are discussed.     

Eine integrative Theorie des Problemlösens in Gruppen: Problemlöseprozess und Problemlöseerfolg

This paper is the first paper in a three-part article series presenting an integrative theory of problem solving in groups on the basis of theory and research on group processes, problem solving and decision making. Group problem solving is differentiated into three main focuses of action, namely taskwork, group organisation and socio-emotional regulation. The present paper focuses on aspects of group organization. A theory of the structure of group mental models is developed. The mental model of problem solving groups is differentiated into a short-term and a long-term memory system. Under each memory system, several memory units are proposed containing declarative and procedural knowledge on aspects of the problem at hand and aspects of the group. Based on the assumption that success in problem solving results from the group’s success in solving various subproblems, recommendations for structuring the problem solving process are being drafted. It is suggested that during an initial orientation stage all occurring subproblems be rated according to their need for action and stored in the short term memory system. In the following action stage, the various subproblems stored in the short term memory system should be worked off in the order of their respective need for action. Based on characteristics of the subproblems at hand and on situative constraints, propositions concerning the resources needed for belabouring the various subproblems are established. Consequences with regard to the working mode of the group are derived.     

Convexity-based clustering criteria: theory,algorithms, and applications in statistics

This paper deals with the construction of optimum partitions of for a clustering criterion which is based on a convex function of the class centroids as a generalization of the classical SSQ clustering criterion for n data points. We formulate a dual optimality problem involving two sets of variables and derive a maximum-support-plane (MSP) algorithm for constructing a (sub-)optimum partition as a generalized k-means algorithm. We present various modifications of the basic criterion and describe the corresponding MSP algorithm. It is shown that the method can also be used for solving optimality problems in classical statistics (maximizing Csiszárs -divergence) and for simultaneous classification of the rows and columns of a contingency table.