Search results for "REGION"
showing 10 items of 4910 documents
Fracture resistance and the mode of failure produced in metal-free crowns cemented onto zirconia abutments in dental implants.
2019
The purpose of the investigation was to analyze fracture resistance and mode of failure of zirconium oxide (zirconia) abutments placed on dental implants bearing crowns of different esthetic materials: zirconia, lithium disilicate (LDS), and nano-ceramic resin, for replacing single teeth in the anterior sector. Eighty implant-abutment-crown units were divided into four groups: Group T-MC (control): 20 metal-ceramic crowns cemented onto titanium abutments; Group Z-Z: 20 zirconia crowns on zirconia abutments; Group Z-LD: 20 lithium disilicate crowns on zirconia abutments; and Group Z-NCR: 20 nano-ceramic resin crowns on zirconia abutments. Specimens underwent a fatiguing process (dynamic load…
Primary cilia are required for cerebellar development and Shh-dependent expansion of progenitor pool
2008
Cerebellar granule cell precursors (GCPs), which give rise to the most abundant neuronal type in the mammalian brain, arise from a restricted pool of primary progenitors in the rhombic lip (RL). Sonic hedgehog (Shh) secreted by developing Purkinje cells is essential for the expansion of GCPs and for cerebellar morphogenesis. Recent studies have shown that the primary cilium concentrates components of Shh signaling and that this structure is required for Shh signaling. GCPs have a primary cilium on their surface [Del Cerro, M.P., Snider, R.S. (1972). Studies on the developing cerebellum. II. The ultrastructure of the external granular layer. J Comp Neurol 144, 131-64.]. Here, we show that 1)…
Photoperiod-temperature and neuroblast proliferation-migration in the adult lizard cortex.
1997
The lizard medial cortex (a zone homologous to the mammalian fascia dentata) shows delayed postnatal neurogenesis throughout the lifetime of these animals. Experimental lesioning of this area is followed by neuronal regeneration, a unique phenomenon in the adult amniote telencephalon. The differential effects of temperature and photoperiod on postnatal neurogenetic activity were studied using tritiated thymidine pulses and posterior autoradiography as well as proliferating cell nuclear antigen (PCNA) immunostaining. Long (summer) photoperiods increased the number of proliferating neuroblasts in the ependymal neuroepithelium. Cold (winter) temperature prevented migration of the newly generat…
Alterations of regional cerebral blood flow and oxygen saturation in a rat sinus-vein thrombosis model.
1996
Background and Purpose The pathophysiology of sinus-vein thrombosis (SVT) in patients and experimental animals is still poorly understood. This study was designed to examine and further elucidate the pathophysiological sequence of events, especially the relationship between local and regional blood flow and hemoglobin oxygen saturation (HbSO 2 ) detected at identical locations. The use of both parameters as outcome indicators should be compared. Methods SVT was induced by ligation of the superior sagittal sinus (SSS) and slow injection of kaolin-cephalin suspension into the SSS in rats. Regional cerebral blood flow (rCBF) was assessed by laser-Doppler flowmetry together with regional HbSO …
Impacts du changement climatique sur la phénologie du Pinot noir en Bourgogne
2013
The viticulture is an important economic and cultural sector in Burgundy. The current climate change raises a number of issues including its impact on crops. In this thesis, the idea is to develop a methodology to address the problem: what are the potential impacts of changes in temperature on the phenology of Pinot noir in Burgundy for years 2031-2048?The evolution of temperatures in Burgundy since 1961 is characterized by a positive temperature shift at the end of the 1980s followed by a period where the temperature increases of about 1.5 ° C.One of the interests of this thesis is to develop, following a strategy developed during the thesis, a spatial database conducted over the period 19…
CtsR is the master regulator of stress response gene expression in Oenococcus oeni.
2005
ABSTRACT Although many stress response genes have been characterized in Oenococcus oeni , little is known about the regulation of stress response in this malolactic bacterium. The expression of eubacterial stress genes is controlled both positively and negatively at the transcriptional level. Overall, negative regulation of heat shock genes appears to be more widespread among gram-positive bacteria. We recently identified an ortholog of the ctsR gene in O. oeni . In Bacillus subtilis , CtsR negatively regulates expression of the clp genes, which belong to the class III family of heat shock genes. The ctsR gene of O. oeni is cotranscribed with the downstream clpC gene. Sequence analysis of t…
Capitolo VIII della Carta dell’ONU e modelli di azione militare regionale
2019
This contribution deals with relations between regional organizations and the UN Security Council under Chapter VIII of the UN Charter. In this respect, the most recent trends are a shift from subsidiarity to a more equal partnership between these two subjects. The two models of action by delegation or authorization of the Security Council are in fact autonomous. This is demonstrated by the preparatory works of the UN Charter and subsequent practice. The model of authorized regional action enriches the range of instruments that the United Nations Charter provides for the maintenance of peace and collective security.
Review of the Neotropical Charipinae (Hymenoptera, Cynipoidea, Figitidae)
2013
A review of the Neotropical Charipinae is given, with 35 species from four genera: Alloxysta, Apocharips, Dilyta and Phaenoglyphis. One new species, Alloxysta centroamericana Ferrer-Suay & Pujade-Villar sp. nov. is described; six Alloxysta species, Alloxysta citripes (Thomson, 1862), Alloxysta fracticornis (Thomson, 1862), Alloxysta melanogaster (Hartig, 1841), Alloxysta piceomaculata (Cameron, 1886), Alloxysta postica (Hartig, 1841) and Alloxysta pusilla (Kieffer, 1902), are recorded for the first time from the Neotropical region; 10 new records for earlier known species are also given. Diagnoses and a key to all species are also provided.
Effects of overabundant nitrate and warmer temperatures on charophytes: The roles of plasticity and local adaptation
2018
Global change effects, such as warming and increases in nitrogen loading, alter vulnerable Mediterranean aquatic systems, and charophytes can be one of the most affected groups. We addressed the possible interaction between these factors on two populations of the cosmopolitan charophytes Chara hispida and Chara vulgaris. Populations were taken from two different environments, a nitrate-poor mountain lake and a nitrate-rich Mediterranean coastal spring. The laboratory experiment had a 2 × 2 factorial design based on two nitrate levels (similar to and double the local conditions) and two temperatures. Increased temperatures favoured the growth of the four populations, but an increase in nitra…
Preferential solvation of poly(methyl methacrylate) and a bisphenol A diglycidyl ether by size-exclusion chromatography
2004
The preferential adsorption coefficient, lambda, of poly(methyl methacrylate), PMMA, in solutions formed by an epoxy resin in tetrahydrofuran (THF), was studied by size-exclusion chromatography (SEC). Only PMMA of lowest molar mass was preferentially solvated by epoxy but at low concentrations of epoxy in the mixture. At higher epoxy content PMMA was preferentially solvated by THF. A simultaneous and competitive solvation between the specific interactions PMMA-epoxy and the self association of epoxy at high concentrations would be the responsible of this inversion point. The more compacted coil of PMMA of higher molecular weights in solution could explain the lack of interaction of these po…