15,500 research outputs found
PARADOXISM SI POSTMODERNISM in creatia lui FLORENTIN SMARANDACHE
No full textParcă vrând să fie in ton cu paradoxismul, Florentin Smarandache este ... paradoxal: atât despre omul de stiintă, cât si despre smarandachism s-au scris deja zeci de cărţi, studii si articole, insa paradoxistul numarul unu al lumii este putin cunoscut in tara sa de origine
Şantierul arheologic Păcuiul lui Soare (r. Adamclisi) / Le chantier archéologique de Păcuiul lui Soare
No full textDiaconu Petre, Popa R., Anghelescu Niţă. Şantierul arheologic Păcuiul lui Soare (r. Adamclisi) / Le chantier archéologique de Păcuiul lui Soare. In: Materiale şi cercetări arheologice, N°8 1962. pp. 713-722
Şantierul arheologic Păcuiul lui Soare (r. Adamclisi) / Le chantier archéologique de Păcuiul lui Soare
No full textDiaconu Petre. Şantierul arheologic Păcuiul lui Soare (r. Adamclisi) / Le chantier archéologique de Păcuiul lui Soare. In: Materiale şi cercetări arheologice, N°7 1961. pp. 599-608
Săpăturile de la Păcuiul lui Soare (r. Adamclisi, reg. Constanţa) / Les fouilles de Păcuiul lui Soare
No full textDiaconu Petre. Săpăturile de la Păcuiul lui Soare (r. Adamclisi, reg. Constanţa) / Les fouilles de Păcuiul lui Soare. In: Materiale şi cercetări arheologice, N°6 1959. pp. 653-666
Săpăturile arheologice de la Păcuiul lui Soare (r. Băneasa, reg. Constanţa) / Les fouilles archéologiques de Păcuiul lui Soare
No full textNestor Ion, Diaconu Petre. Săpăturile arheologice de la Păcuiul lui Soare (r. Băneasa, reg. Constanţa) / Les fouilles archéologiques de Păcuiul lui Soare. In: Materiale şi cercetări arheologice, N°5 1959. pp. 587-592
IN VIVO IMAGING OF STEM CELL MEDIATED TREATMENT IN A MOUSE MODEL OF SPINAL CORD INJURY
No full textIntroduction: The use of adult stem cells in cell-mediated therapies is an area of considerable interest within tissue regeneration research. However, important variables such as the distribution of the injected cells, cell survival, target organ localisation cell proliferation and differentiation cannot be evaluated in vivo by using classical imaging approaches. This study propose multiple labelling protocols for in vivo visualisation by MRI, nuclear imaging and BLI of adult murine neural stem cell-mediated therapy, in spinal cord injury animal models. Methods: Murine neural stem cells (mNSCs) were directly labelled with different amounts of SPIOs (0 - 100 - 200 - 400 μg Fe/ml) in the culture medium and incubated with iron labelled medium for 24, 48 or 72 h in presence of carriers such as poly-L-Lysine (PLL), polybrene (PB) and protamine sulphate (PS). PLL and PS were tested at different ratio (Fe/PLL 1:0,03, 1:0,06 and 1:0,09 and Fe/PS 1:0,025 and 1:0,05). Labelled cells were analysed for viability, iron content (Perl’s Staining and spectrophotometer analysis), morphology, staminality and differentiation capability. After the labelling protocol set up, the loaded cells were injected into the tail vein of a spinal cord injury murine model and their distribution was followed by MRI for two months. Initial cell distribution was also followed by nuclear imaging after cell labelling with 111In-oxine (60 μCi/106 cells). Cells localization, distribution e viability, over time, were analysed in vivo by BLI after injection of mNCS infected with a viral vector expressing Luciferase under a PGK constitutive promoter (PLW vector). Results: the iron content/cell increased in proportion to the incubation time and to the iron concentration in the medium and in relation to different carriers (PLL, PB and PS) in labelled mNSCs. Longer incubation time (48 and 72h) and higher iron concentration (400 μg Fe/ml) resulted in marked toxicity and lower cell viability. The use of PB and PLL, as carriers, didn’t produce any increase of the labelling efficiency. The incubation for 24h with 200 μg Fe/ml in presence of different amount of PS didn’t influence significantly the cell viability and the proliferation rate. Furthermore, the percentage of iron-positive cells and the iron content/cell increased in proportion to the PS content in the medium even if higher amount of PS (Fe/PS 1:0.05 ratio) resulted in an aberrant morphology. For this reason, 200 μg Fe/ml incubated with Fe/PS 1:0.025 ratio for 24h, has been chosen as the best labelling condition. Labelled cells were able to form new neurospheres and maintained the nestin expression demonstrating the maintenance of self-renewal capability and stem cell features and were also able to differentiate, as confirmed by β-tubulin III and GFAP expression analysis. Nuclear imaging confirmed initial distribution to filter organs while MRI allowed to detect the presence of an iron signal due to stem cell localization into the lesion site since 7 days after injection. BLI permitted to demonstrate the viability of PLW infected mNSCs migrated at the lesion site and supported the MRI data. Conclusions: These results permitted to conclude that NSCs can be efficiently labelled with different molecules without significantly perturbing physiological stem cell features and self-renewal capability. These labelling protocols can be applied for the in vivo visualisation by MRI, nuclear imaging, and BLI of the distribution of stem cells after their transplantation into murine model of disease
Pierre-Étienne Will and R. Bin Wong, with the collaboration of James Lee, Peter C. Perdue and Jean C. Oi. Nourish the People. The State Civilian Granary System in China, 1650-1850. 1991. (Michigan Monographs in Chinese Studies, volume 60)
No full textTs'ui-Jung Lui. Pierre-Étienne Will and R. Bin Wong, with the collaboration of James Lee, Peter C. Perdue and Jean C. Oi. Nourish the People. The State Civilian Granary System in China, 1650-1850. 1991. (Michigan Monographs in Chinese Studies, volume 60). In: Études chinoises, vol. 12, n°1, Printemps 1993. pp. 188-190
L'émergence d'une théorie de la communication organisante. Entretien avec James R. Taylor
No full textCet article est le fruit d'un entretien avec le professeur émérite James R. Taylor, fondateur du Département de communication de l'Université de Montréal et figure reconnue dans le domaine canadien des médias, mais surtout auteur d'une théorie originale de la communication organisante, dont il retrace ici l'émergence. Ses concepts et sources d'inspiration - le résultat d'un parcours atypique, iconoclaste et inspirant - distinguent sa pensée des autres courants théoriques et historiques du champ de la communication organisationnelle. Une originalité telle, qu'on lui reconnaît aujourd'hui la paternité de « l'École de Montréal », un influent regroupement informel de chercheurs en communication qui participent - en divers lieux et par diverses voies - à approfondir et renouveler les intuitions radicales du professeur Taylor. C'est ce parcours distinctif qui forme la substance de cet entretien avec un chercheur toujours passionné, et considérablement actif et prolifique encore aujourd'hui, qui nous offre même un aperçu exclusif de ses prochaines publications
The accessory optic system: basic organization with an update on connectivity, neurochemistry, and function
No full textThe accessory optic system (AOS) is formed by a series of terminal nuclei receiving direct visual information from the retina via one or more accessory optic tracts. In addition to the retinal input, derived from ganglion cells that characteristically have large receptive fields, are direction-selective, and have a preference for slow moving stimuli, there are now well-characterized afferent connections with a key pretectal nucleus (nucleus of the optic tract) and the ventral lateral geniculate nucleus. The efferent connections of the AOS are robust, targeting brainstem and other structures in support of visual-oculomotor events such as optokinetic nystagmus and visual–vestibular interaction. This chapter reviews the newer experimental findings while including older data concerning the structural and functional organization of the AOS. We then consider the ontogeny and phylogeny of the AOS and include a discussion of similarities and differences in the anatomical organization of the AOS in nonmammalian and mammalian species. This is followed by sections dealing with retinal and cerebral cortical afferents to the AOS nuclei, interneuronal connections of AOS neurons, and the efferents of the AOS nuclei. We conclude with a section on Functional Considerations dealing with the issues of the response properties of AOS neurons, lesion and metabolic studies, and the AOS and spatial cognition
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