On the high affinity of 8-cyclohexylcaffeine for the presynaptic inhibitory adenosine receptor present in rat motor nerve terminals

Rat neuromuscular junction was used to study the characteristics of presynaptic A1 adenosine receptors. We investigated the ability of the 8-substituted caffeine, 8-cyclohexylcaffeine (CHC), as well as of 1,3,8-substituted xanthines, 1,3-dipropyl-8-p-sulfophenylxanthine (DPSPX) and 8-p-sulfophenyl-1-isoamyl-3-isobutylxanthine (SPIIBX) to antagonize the inhibitory effect of 2-chloroadenosine on the amplitude of nerve-evoked twitches of the rat phrenic-hemidiaphragm, and we compared the affinity of these xanthines with that of 1,3-dipropyl-8-cyclopenthylxanthine (DPCPX). CHC, DPSPX and SPIIBX in a near parallel manner shifted to the right the log concentration-response curve for the inhibitory effect of 2-chloroadenosine on nerve-evoked twitch amplitude. Linear Schild plots with slopes near to unity were obtained for all these xanthines. The order of potency of the xanthines was DPCPX (Ki = 0.53 nM) > DPSPX (38 nM) = CHC (41 nM) > SPIIBX (404 nM). The affinities of DPSPX and SPIIBX for the A1 receptor at the rat neuromuscular junction are in agreement with the affinities described for A1 receptors at brain membranes. The now reported affinity of CHC for the presynaptic A1 receptor is 683 times higher than that obtained in binding studies in rat brain membranes, and is only 49 times higher than that obtained in functional assays (adenylate cyclase activity) in non-neuronal preparations (rat fat cells).     

Composition-based prediction of dielectric properties of foods

Prediction of accurate dielectric property data from fundamental principles for systems as complex as foods has not been possible. Simple prediction models based on easily measurable composition data can serve many useful purposes. Literature dielectric data on foods and their composition were statistically correlated. Dielectric data on salt solutions were measured to explain some of the results. When composition data were not available, standard handbook compositions were used. Inclusion of all types of foods (meats, fruits, and vegetables) inhibited any useful correlation with composition. Based on a smaller data set of meats, both dielectric constant and loss increased with water and salt content. Dielectric constant generally decreased with temperature whereas dielectric loss decreased with temperature at lower salt concentrations and increased with temperature at higher salt concentrations.     

An extended Petri net model for normal logic programs

This paper presents an application of the concepts of siphons (deadlocks) and inhibitor arcs in Petri net theory to logic programs with negations. More specifically, an extended Petri net is used to model function-free normal logic programs. In this model, because of the presence of inhibitor arcs, the arbitrary applications of firing rule may cause a contradictory situation. We suggest two directions to avoid contradictions: greedy and secure applications of firing rule. We choose the secure application and show that this is a direct translation of the well-founded semantics in the net model. Furthermore, we show that the greatest unfounded set corresponds to the greatest siphon in Petri net theory when we delete the transitions disabled by the secure application of firing rule, and that the property of siphon simplifies the computation of well-founded semantics for logic programs. We also propose the reduced-Petri-net method by which we can reduce an extended Petri net to a Petri net without inhibitor arcs and compute the well-founded model by iterative applications of this transformation using conventional application of firing rule     

In conflict with conflict

In a qualitative, retrospective case study to identify, describe, and develop a theoretical analysis of perceived group process among female nursing educators/administrators, the term "conflict," as traditionally defined in discussions of "conflict management strategies," was rejected. The term did not readily fit with the management styles of the 27 female nurse educators and administrators. Participants rejected "conflict" as a term. The word was deliberately avoided. In fact, conflict rejection was a specific administrative process identified as part of the successful working of the group over the three-year period studied. This finding indicates a break with traditional male-oriented literature and therefore may have implications for future research into conflict management strategies, especially into successful management strategies used by women and health care professionals.     

The ECLW Collaborative Study: III. Training and reliability of ICD-10 psychiatric diagnoses in the general hospital setting--an investigation of 220 consultants from 14 European countries. European Consultation Liaison Workgroup

A comprehensive training program for reliable use of the ICD/10 in Consultation-Liaison (C-L) psychiatry was conducted with 220 psychiatrists and psychologists from 14 European countries. The training included rating of written test cases and development of a coding manual to avoid diagnostic pitfalls not addressed in the ICD-10 manual. Following this training, all consultants rated 13 written case histories. One hundred sixty-seven consultants (76%) had a kappa (kappa) of at least 0.70. Only 13 (6%) had a kappa 0.40. The percentage of high reliability raters was evenly distributed among the different countries. Consultants had some problems in the differentiation between adjustment disorders and depressive disorders, and in the classification of disorders where ICD-10 differs from the DSM-III-R system. National biases in diagnostic practice were found with regard to the "case" concept and the role of alcohol in confusional states. Finnish consultants coded "no psychiatric disorder" significantly more often, whereas German and Italian consultants attributed delirious state more often to alcohol than consultants from other European countries. The study demonstrates that it is possible to achieve acceptable interrater reliability in applying the ICD-10 guidelines, through training programs designed for C-L psychiatrists and psychologists. Nevertheless, this first cross-national study shows the importance of addressing differences in national diagnostic practice.     

Opportunities for small and medium enterprises in the innovation and marketing of organic food: investigating consumers’ purchase behaviour of organic food products in Victoria,Australia

This research study investigates Victorian consumers’ understanding, awareness and perceptions of organic food products. Analysis of the quantitative data revealed that there are three major segments of consumers, i.e., pro-organics, reluctant consumers and organic sceptics. The buying and usage pattern of these segments has been identified as also their demographic profile. The findings of this study are strategically important for small and medium size organic food producers. They would be better able to practise and implement differentiation strategies for the three identified segments of customers, thus allowing their marketing teams to emphasise the beneficial attributes of organic food products.