En este artículo extendemos el espectro de las lógicas con la Conversa de la Propiedad Ackermann. Definimos y axiomatizamos lógicas preposicionales intuicionistas positivas, lógicas subintuicionistas ...y lógicas intuicionistas con la Conversa de la Propiedad Ackermann. Especialmente interesante es la versión de la negación intuicionista propia de algunos de estos sistemas. Presentamos semánticas de tipo relacional ternario para cada una de las lógicas que estudiamos en este trabajo. The range of propositional logics with the Converse Ackermann Property is proved to be wider than currently assumed. Subintuitionistic, positive intuitionistic and intuitionistic propositional logics with the Converse Ackermann Property are defined and axiomatized. A particular version of intuitionistic negation is involved in some of these systems. Complete ternary relational semantics are offered for all logics studied in the paper.
Vers un ailleurs prometteur Acheson, Julianna; Allen, Peter M; Bley, Daniel ...
Graduate Institute Publications eBooks,
1993
eBook, Book
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HERMANN-MICHEL HAGMANN Secrétaire général Laboratoire de démographie économique et sociale Université de Genève JEAN-LUC MAURER Directeur Institut universitaire d'études du développement Genève
More than a decade after the discovery of graphene, ballistic transport in nanostructures based on this intriguing material still represents a challenging field of research in two-dimensional ...electronics. The presence of rough edges in nanostructures based on this material prevents the appearance of truly ballistic electron transport as theo\-re\-tically predicted and, therefore, not well-developed plateaus of conductance have been revealed to date. In this work we report on a novel implementation of the cryo-etching method, which enabled us to fabricate graphene nanoconstrictions encapsulated between hexagonal boron nitride thin films with unprecedented control of the structure edges. High quality smooth nanometer-rough edges are characterized by atomic force microscopy and a clear correlation between low roughness and the existence of well-developed quantized conductance steps with the concomitant occurrence of ballistic transport is found at low temperature. In par\-ti\-cu\-lar, we come upon exact 2\(e^{2}/h\) quantization steps of conductance at zero magnetic field due to size quantization, as it has been theoretically predicted for truly ballistic electron transport through graphene nanoconstrictions.
Four subminimal negation completions of the basic positive relevance logic are defined, isolating weak negative principles of contraposition, double negation and reductio by means of weak ...constructive falsity constants.
In order to characterize the acidic ribosomal proteins immunologically and functionally, a battery of monoclonal antibodies specific for L44, L44' and L45, the three acidic proteins detected in ...Saccharomyces cerevisiae, were obtained. Eight monoclonal antibodies were obtained specific for L45, three for L44' and one for L44. In addition, two mAbs recognizing only the phosphorylated forms of the three proteins were obtained. The specific immunogenic determinants are located in the middle region of the protein structure and are differently exposed in the ribosomal surface. The common determinants are present in the carboxyl end of the three proteins. An estimation of the acidic proteins by ELISA indicated that, in contrast to L44 and L45, L44' is practically absent from the cell supernatant; this suggests that protein L44' does not intervene in the exchange that has been shown to take place between the acidic proteins in the ribosome and in the cytoplasmic pool. It has also been found that, while IgGs specific for L44 and L45 do not inhibit the ribosome activity, the anti-L44' effectively blocks the polymerizing activity of the particles. These results show for the first time that the different eukaryotic acidic ribosomal proteins play a different functional role.
Our laboratory has been involved in the study of glutathione-sulfhydryl-transferase-pi (GST-pi) for several years. We have recently observed that during haematopoiesis in BMSC liquid cultures from ...CML patients who were candidates for transplant GST-pi was expressed in presumably malignant cells during different stages of cellular maturation. To confirm this finding, in the present work we are detecting GST-pi expression by immunofluorescence in BCR-ABL+ and BCR-ABL- cells done by FISH of PB from 30 CML patients during different clinical status: treatment (T), hematological relapse (R), blastic crisis (BC) or post-allotrasplant (PT). As well as in PB from 30 Blood-Bank donors. The results were %BCR-ABL+ GST-pi+ cells: T = 1-67, R = 33-69, BC = 90-100 and PT = 1-2; %BCR-ABL- GST-pi+ cells: T = 2-31, R = 5-18, BC = 0-10 and PT = 2-5; %BCR-ABL- GST-pi- cells: T = 2-97, R = 13-62, BC = 0 and PT = 93-96; %BCR-ABL+ GST-pi- cells: T = 0, R = 0, BC = 0 and PT = 0. GST-pi was not expressed in donor cells. The results obtained confirm our previous observations and suggest that GST-pi expression might be used for the evaluation of the minimal residual disease in CML patients.
During the immune response to rat tumor cells there is participation of the thymus and the spleen via the synthesis of antibodies and immune cellular elements. During this process different mRNAs of ...both organs are synthesized. Here is presented the infradian variation of mRNA synthesis of immunized rat thymus and spleen to Novikoff's Hepatoma (NH) cells. These cells were maintained and transferred in ascitic manner in the peritoneal cavity of Sprague Dawley male rats standardized with 12 hours (h) of light and 12 h of darkness. Aliquots of 1 x 10 6 NH dead cells were innoculated intraperitoneally into rats after being exposed during 30 minutes to ultraviolet light and incubated at 37°C with 50 U of neuraminidase/ml during 70 minutes. Groups of 3 controls and 3 immunized rats were killed at the same circadian timepoint (10 a.m.) under anesthesia every 3 days during a span of 18 days. At each time spleens and thymus of each group were harvested and pooled in order to isolate their mRNA. Isolation of the rRNA and mRNA of control and immunized rats was performed by affinity chromatography employing oligothymidylic acid cellulose columns. Analysis of variance demonstrated a significant (p <0.03) higher synthesis of immune (i)mRNA of rat spleen, starting on 3 days after immunization with NH cells and reaching the higher levels on 6 and 18 days after immunization and lower levels on 9, 12, 15 days after immunization. Same effect is also observed in the synthesis of imRNA rat thymus 6 days after immunization, however, there was not difference with the intact rat thymus mRNA on 3, 9 and 12 days after immunization. Interestingly, there was observed an increased synthesis of intact rat thymus mRNA 15 days after inoculation. During this cyclic synthesis of thymic and spleenic imRNAs it seems that the spleen plays the role of a possible pacemaker of the coordinated immune response to NH cells.
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