The incidence of unpleasant dreams after sub-anaesthetic ketamine

Ketamine is an N-methyl-D-aspartate (NMDA)receptor antagonist with psychotogenic effects and for whichthere are diverse reports of whether pleasant or unpleasantdreams result during anaesthesia, post-operatively or aftersub-anaesthetic use. The aim was to assess in healthy volunteers the incidence ofunpleasant dreams over the three nights after receiving asub-anaesthetic dose of ketamine, in comparison to placebo,and with retrospective home nightmare frequency as acovariate.Thirty healthy volunteers completed questionnairesabout retrospective home dream recall and were then giveneither ketamine or placebo. Ketamine resulted in significantly more meandream unpleasantness relative to placebo and caused athreefold increase in the odds ratio for the incidence of anunpleasant dream. The number of dreams reported over thethree nights did not differ between the groups. Theincidence of unpleasant dreams after ketamine use waspredicted by retrospectively assessed nightmare frequencyat home.Ketamine causes unpleasant dreams over thethree post-administration nights. This may be evidence of aresidual psychotogenic effect that is not found on standardself-report symptomatology measures or a result of disturbedsleep electrophysiology. The results have theoretical implications for the relationship between nightmares and schizotypy

Bioreactors as engineering support to treat cardiac muscle and vascular disease

Cardiovascular disease is the leading cause of morbidity and mortality in the Western World. The inability of fully differentiated, load-bearing cardiovascular tissues to in vivo regenerate and the limitations of the current treatment therapies greatly motivate the efforts of cardiovascular tissue engineering to become an effective clinical strategy for injured heart and vessels. For the effective production of organized and functional cardiovascular engineered constructs in vitro, a suitable dynamic environment is essential, and can be achieved and maintained within bioreactors. Bioreactors are technological devices that, while monitoring and controlling the culture environment and stimulating the construct, attempt to mimic the physiological milieu. In this study, a review of the current state of the art of bioreactor solutions for cardiovascular tissue engineering is presented, with emphasis on bioreactors and biophysical stimuli adopted for investigating the mechanisms influencing cardiovascular tissue development, and for eventually generating suitable cardiovascular tissue replacements

WEAK IMPLICATION ON GENERALIZED LUKASIEWICZ ALGEBRAS OF ORDER n

In this note, bearing in mind the important role that weak implication played in the study of Lukasiewicz algebras of order n, we introduce an implication operation on m-generalized Lukasiewicz algebras of order n. As this operation generalizes the one indicated above, we will call it with the same name. The deductive systems associated with this implication enable us to establish an isomorphism between the congruence lattice of an m-generalized Lukasiewicz algebras of order n A and the lattice of all the deductive systems of A. This result turns out to be quite useful for characterizing the principal congruences on these algebras simplier than the one described in the above mentioned paper

Functional monadic nn-valued Łukasiewicz algebras

summary:Some functional representation theorems for monadic $n$-valued Łukasiewicz algebras (qLk$_{n}$-algebras, for short) are given. Bearing in mind some of the results established by G. Georgescu and C. Vraciu (Algebre Boole monadice si algebre Łukasiewicz monadice, Studii Cercet. Mat. 23 (1971), 1027–1048) and P. Halmos (Algebraic Logic, Chelsea, New York, 1962), two functional representation theorems for qLk$_{n}$-algebras are obtained. Besides, rich qLk$_{n}$-algebras are introduced and characterized. In addition, a third theorem for these algebras is presented and the relationship between the three theorems is shown

Monadic n×m\boldsymbol n\boldsymbol \times \boldsymbol m-valued Łukasiewicz-Moisil algebras

summary:Here we initiate an investigation into the class $\boldsymbol m\boldsymbol L\boldsymbol M_{\boldsymbol n\boldsymbol \times \boldsymbol m}$ of monadic $n\times m$-valued Łukasiewicz-Moisil algebras (or $mLM_{n \times m}$-algebras), namely $n\times m$-valued Łukasiewicz-Moisil algebras endowed with a unary operation. These algebras constitute a generalization of monadic $n$-valued Łukasiewicz-Moisil algebras. In this article, the congruences on these algebras are determined and subdirectly irreducible algebras are characterized. From this last result it is proved that $\boldsymbol m\boldsymbol L\boldsymbol M_{\boldsymbol n\boldsymbol \times \boldsymbol m}$ is a discriminator variety and as a consequence, the principal congruences are characterized. Furthermore, the number of congruences of finite $mLM_{n \times m}$-algebras is computed. In addition, a topological duality for $mLM_{n \times m}$-algebras is described and a characterization of $mLM_{n \times m}$-congruences in terms of special subsets of the associated space is shown. Moreover, the subsets which correspond to principal congruences are determined. Finally, some functional representation theorems for these algebras are given and the relationship between them is pointed out