Van vleck paramagnetism of the diluted intermetallic compounds Pr1−x Y x Ni5 at fields up to 15 T

We have measured the 16 Hz susceptibility of the diluted Van Vleck paramagnets Pr_1−x Y _x Ni₅ withx=0.00, 0.05, 0.10. 0.20 at temperatures 1.5 K≤T≤50 K and magnetic fields up to 15T. Their Van Vleck type magnetic susceptibility χ(T, B, x) strongly depends on the field atB≥6 T. The temperatureT _max(B, x) of the maximum of χ(T, B, x) decreases at increasing the field from zero to 15 T by approximately one order of magnitude for all Pr_1−x Y _x Ni₅ compounds. Changing the dilutionx from zero to 0.20, the field whereT _max(B, x) strongly drops is increased from 9 T to 11 T. Our data agree qualitatively with the predictions of a point charge model which considers the Zeeman term in addition to the electronic exchange and the dominating crystal field contributions.     

Analysis of a structural polymorphism in the 5-HT2A receptor and clinical response to clozapine

Clozapine is an atypical antipsychotic with affinity for a broad range of receptors, including serotonin (5-HT) and dopamine receptors. It is successful in treating about 60% of patients refractory to other antipsychotic drugs. Since genetic variation in clozapine's neurotransmitter receptor targets may affect clinical response through altering drug binding or receptor expression, we have studied a His452Tyr polymorphism in the 5-HT2A receptor (HTR2A) in a sample of 153 schizophrenic patients undergoing clozapine treatment and 178 normal controls. An association was found between the allele Tyr452 and poor clinical response.     

Processing of nested and cross-serial dependencies: an automaton perspective on SRN behaviour

Language processing involves the identification and establishment of both nested (stack-like) and cross-serial (queue-like) dependencies. This paper analyses the behaviour of simple recurrent networks (SRNs) trained to handle these types of dependency individually and simultaneously. We provide new converging evidence that SRNs store sequences in a fractal data structure similar to a binary expansion. We provide evidence that the process of recalling a stored string by an SRN depletes the stored data structure, much like the operations of a symbolic stack or queue. Trained networks do not seem to operate like random access arrays, where a pointer into a data structure can retrieve data without altering the contents of the data structure. In addition, we demonstrate that networks trained to model both types of dependencies do not implement a more complex, but unified, representation, but rather implement two independent data structures, similar to a stack and queue.     

Pseudomonas aeruginosa as a cause of infectious diarrhoea

Pseudomonas aeruginosa is not generally considered a cause of infectious diarrhoea. However, it was the predominant organism isolated from the faeces of 23 unrelated, hospital outpatients investigated in the course of a year for persistent (> 1 week duration) diarrhoea. To investigate the possible aetiological role of P. aeruginosa, these patient histories were reviewed and a selection of their faecal isolates were investigated in vitro (n > or = 10) and in vivo (n = 2) for virulence. The patients had a mean age of 60 years, were receiving antibiotics and/or had an underlying illness. Extensive microbiological investigations identified no other potential or recognized enteropathogen in the faeces of 20 of these patients. More than 40% of the isolates tested were able to adhere to HEp-2 cells and exhibited twitching motility (type IV pili), properties indicative of their ability to colonize the human intestine. Cytotoxic activity was demonstrated in bacterium-free cell supernatants of over 80% of isolates; supernatants of four isolates tested in infant mice were weakly enterotoxigenic. Two isolates intragastrically inoculated into clindamycin pre-treated rats established persistent infections and induced signs and symptoms of enteritis. Overall these findings suggest that P. aeruginosa can cause diarrhoea particularly in immunodeficient individuals.     

Matching of the water states of products and zeolite during contact adsorption drying

The mixing of dehydrated zeolites with product particles leads to drying of the product, owing to the decrease in relative humidity of the environment and increase the temperature of the mixture, due to the release of adsorption heat. The analysis of the conventional one-stage contact drying process showed a significant mismatching in the water states of the product and the zeolite during drying. A two-stage drying process is proposed for harmonization of the water state of both product and sorbent. The significant advantage of the two-stage drying over one-stage regarding the degree of drying of the product, the utilization of the zeolite adsorption capacity and the duration of the process were experimentally confirmed.     

Optimum design of machine systems in R & D performing laboratoriesПpoeктиpoвaниe мaщиннЫч cиcтeм в тayЧнo-иccлeдoвaтeльcкич лaвopтpии

Research and Development in machine systems is often being carried out by mathematical programming. The purpose of this paper is to review modern work in mechanisms design and to familiarize the reader with the problem of design optimization with multiple objectives, as applied to machine systems. A new optimization method called selective synthesis is discussed. It is characterized by two basic steps: (a) generating a fixed set of design alternatives, and (b) decision making (optimization) in cascade. Two additional steps, namely evaluation of unclear preferences and replacing the original decision problem with new one, are applied when necessary. An example problem is resolved, proving the potential application of selective synthesis on the practice of R & D performing laboratories.