Conscious Brain-to-Brain Communication in Humans Using Non-Invasive Technologies

Human sensory and motor systems provide the natural means for the exchange of information between individuals, and, hence, the basis for human civilization. The recent development of brain-computer interfaces (BCI) has provided an important element for the creation of brain-to-brain communication systems, and precise brain stimulation techniques are now available for the realization of non-invasive computer-brain interfaces (CBI). These technologies, BCI and CBI, can be combined to realize the vision of non-invasive, computer-mediated brain-to-brain (B2B) communication between subjects (hyperinteraction). Here we demonstrate the conscious transmission of information between human brains through the intact scalp and without intervention of motor or peripheral sensory systems. Pseudo-random binary streams encoding words were transmitted between the minds of emitter and receiver subjects separated by great distances, representing the realization of the first human brain-to-brain interface. In a series of experiments, we established internet-mediated B2B communication by combining a BCI based on voluntary motor imagery-controlled electroencephalographic (EEG) changes with a CBI inducing the conscious perception of phosphenes (light flashes) through neuronavigated, robotized transcranial magnetic stimulation (TMS), with special care taken to block sensory (tactile, visual or auditory) cues. Our results provide a critical proof-of-principle demonstration for the development of conscious B2B communication technologies. More fully developed, related implementations will open new research venues in cognitive, social and clinical neuroscience and the scientific study of consciousness. We envision that hyperinteraction technologies will eventually have a profound impact on the social structure of our civilization and raise important ethical issues.     

Elicitation of Necrosis in Vigna unguiculata Walp. by Homogeneous Aspergillus niger Endo-Polygalacturonase and by alpha-d-Galacturonate Oligomers

Endo-polygalacturonase (PG) was purified from a commercial preparation of Aspergillus niger pectinase by means of carboxymethylcellulose chromatography, preparative isoelectric focusing, and gel permeation through Sephadex G-50. The enzyme was electrophoretically homogeneous and consisted of a single polypeptide chain with a molecular weight of 33,500. The enzyme exhibited a specific activity significantly higher than those of purified polygalacturonases from phytopathogenic fungi. Galacturonate oligomers with a degree of polymerization higher than four appeared quickly as products of the enzymic hydrolysis of Napolygalacturonate. The oligomers were later degraded to di- and monogalacturonate. The homogeneous enzyme and growing mycelium of Aspergillus niger separately elicited a necrotic response in cowpea (Vigna unguiculata Walp.) pods. Heat-inactivated PG and PG inactivated with specific antibodies did not elicit necrosis, suggesting that the catalytic activity of the enzyme is necessary for its function as an elicitor. The PG-released oligosaccharides from Vigna cell wall and the galacturonides with a degree of polymerization greater than four separately elicited necrosis, whereas di- and monogalacturonate did not.     

Application of extended Kalman filter to identification of enzymatic deactivation

A recursive estimation scheme, the Extended Kalman Filter (EKF) technique, was applied to study enzymatic deactivation in the enzymatic hydrolysis of pretreated cellulose using a model previously developed by the authors. When no deactivation model was assumed, the results showed no variation with time for all the model parameters except for the maximum rate of cellobiose-to-glucose conversion (r'(m)).The r'(m) variation occurred in two zones with a grace period. A new model of enzymatic hydrolysis of pretreated cellulose deactivation was proposed and validated showing better behavior than the old deactivation model. This approach allows one to study enzyme deactivation without additional experiments and within operational conditions.     

Mathematical modelization of a packed-bed reactor performance with immobilized yeast for ethanol fermentation

The performance of a continuous vertical packed-bed reactor with yeast immobilized in carrageenan gel beads is reported. The study focuses on the mathematical modelling of the steady-state fermentor behavior by means of a tanks-in-series model which includes the intrinsic kinetic model and the external mass transfer and internal diffusion-reaction conditions in the beads.     

Activity of β-galactosidase in homogenates and isolated microvilli fraction of jejunal mucosa from suckling rats

1. beta-Galactosidase activity was studied in homogenates and isolated microvilli fraction of jejunal mucosa from 14-day-old suckling rats. o-Nitrophenyl beta-d-galactoside served as the substrate. 2. The microvilli fraction contains about one-third of the total activity of the original homogenate. 3. The pH optimum of the beta-galactosidase was 3.5 in the total homogenate and supernatant fraction, whereas in the microvilli fraction the maximum activity was at pH5.5. 4. This work gives further support to the view that two beta-galactosidases exist in the jejunal mucosa.     

Germination and regeneration mechanisms in Mediterranean degenerate forests

Abstract. Germination and developmental behaviour during juvenile stages are of importance in relation to succession mechanisms acting on plant communities. This is particularly so in the Mediterranean region, where the climatic summer drought causes stress. We investigated and compared germination and development of four tree species in two parts of the French Mediterranean region where the original dominant tree species (Quercus pubescens) has been largely replaced by Quercus ilex in the southern part, and Castanea sativa in the northern part. Observed differences in germination rates and developmental behaviour, especially shootroot ratio and the role of water supply, suggest that other species may eventually replace the current dominant species.     

Physical characterization of the plasmid pON5300

Summary The antibiotic resistance plasmid Rldrd19Km-which has spontaneously lost its kanamycin resistance marker, and its derivative pON5300, were analysed using the restriction endonucleases SalI, BamHI, HindIII and EcoRI. The fragment patterns were compared with that of the Rldrd19 and the fragments responsible for kanamycin resistance were found to be missing in Rldrd19Km ^– and pON5300. In these plasmids a 7 Mg/mol EcoRI fragment was observed instead of the D (6.3 Mg/mol) fragment of Rldrd19. Further a new 6 Mg/mol EcoRI restriction fragment was observed in pON5300. Using double digestions it was shown that the new fragment does not carry restriction sites for HindIII, BamHI and SalI endonucleases. The non-homology of the analysed plasmid was proved electron microscopically by heteroduplex techniques. The possibility of amplification in the regulatory region for the expression of R-determinants in pON5300 is discussed.     

The mechanism of resistance to streptomycin inEscherichia coli. Functional analysis of the permeability barrier of cells harbouring the Rldrd-19Km plasmid

The mechanism of phenotypically altered SM resistance in mutants of Escherichia coli JC5455 (Rldrd-19Km-) lrs and JC5455 (pON5300) was compared with that of the standard strain JC5455 (Rldrd-19Km-). On analyzing the membrane polypeptides in polyacrylamide gel both mutants were found to possess a protein spectrum different from that of ths standard strain. Transport of D-xylose and L-arginine was the same in all strains, transport of L-proline was decreased in JC5455 (pON5300) which may indicate a mutational interference with energy metabolism. The basic uptake of dihydrostreptomycin was the same in all strains but there were differences after preincubation of cells with streptomycin or glucose. The increased resistance of JC5455 (Rldrd-19Km-) lrs may be due to observed quantitative differences in membrane polypeptides that might play a role in the binding and functional expression of aminoglycoside-3'adenylyl transferase which modifies streptomycin. The increased sensitivity toward streptomycin in JC5455 (pON5300) can be explained by a mutation due to N-methyl-N'-nitro-N-nitrosoguanidine in the host cell since this change of sensitivity to streptomycin could not be transferred by transformation into a nonmutagenized strain. The coincidence of inducibility of increased transport of streptomycin by this antibiotic and the altered frequency of reversion to high levels of streptomycin resistance in JC5455 (pON5300) and in the transformant JC5455 (pON5302) may indicate that the altered reversibility toward phenotypically high resistance to streptomycin is a property of pON5300 and is transferred by transformation.     

Mutation affecting normal colony formation inEscherichia coli K-12

The effect of a mutation in a gene located near thepro marker and determining the normal colony formation and the cell density inEscherichia coli has been analyzed. Thencf mutation has no effect on the permeability of the cell to actinomycin D. On the other hand, a higher level of ATP and a defect in the accumulation of the reserve material in the mutant cell were detected.