Search results for "Centaur"

Collisional Evolution of Trojan Asteroids☆

1997

Abstract We model the collisional evolution of Trojan asteroids using a numerical code which combines recent calculations of the intrinsic collision probabilities and impact speeds in the Trojan swarms (Marzariet al.1996) with our current understanding of the outcomes of high-velocity collisions between asteroid-sized bodies. Using plausible collision parameters and energy scaling of impact strength with size, we obtain a good match to the present Trojan population, as inferred by Shoemakeret al.(1989). The steep slope of the current Trojan size distribution at diameters larger than about 50–100 km is essentially unaltered by the collisional process and must reflect the formative processes …

Cytotoxicity of 40 Egyptian plant extracts targeting mechanisms of drug-resistant cancer cells

2019

Abstract Background The multidrug resistance (MDR) phenotype encounters a major challenge to the success of established chemotherapy in cancer patients. We hypothesized that cytotoxic medicinal plants with novel phytochemicals can overcome MDR and kill MDR-cells with similar efficacy as drug sensitive cells. Purpose We evaluated plant extracts from an unexplored ecosystem in Egypt with unusual climate and nutrient conditions for their activity against sensitive and multidrug-resistant cancer cell lines. Material and methods/study design Methylene chloride: methanol (1:1) and methanol: H2O (7:3) extracts of 40 plants were prepared resulting in a sum of 76 fraction containing compounds with v…

The 2017 May 20 stellar occultation by the elongated centaur (95626) 2002 GZ32

2021

Full list of authors: Santos-Sanz, P.; Ortiz, J. L.; Sicardy, B.; Benedetti-Rossi, G.; Morales, N.; Fernández-Valenzuela, E.; Duffard, R.; Iglesias-Marzoa, R.; Lamadrid, J. L.; Maícas, N.; Pérez, L.; Gazeas, K.; Guirado, J. C.; Peris, V.; Ballesteros, F. J.; Organero, F.; Ana-Hernández, L.; Fonseca, F.; Alvarez-Candal, A.; Jiménez-Teja, Y. Vara-Lubiano, M.; Braga-Ribas, F.; Camargo, J. I. B.; Desmars, J.; Assafin, M.; Vieira-Martins, R.; Alikakos, J.; Boutet, M.; Bretton, M.; Carbognani, A.; Charmandaris, V.; Ciabattari, F.; Delincak, P.; Fuambuena Leiva, A.; González, H.; Haymes, T.; Hellmich, S.; Horbowicz, J.; Jennings, M.; Kattentidt, B.; Kiss, Cs; Komžík, R.; Lecacheux, J.; Marciniak, …

The essential oil composition of Centaurea immanuelis-loewii Degen growing wild in Bulgaria and chemotaxonomy of section Acrocentron

2021

In the present study, the chemical composition of the essential oil from aerial parts of the Balkan endemic, Centaurea immanuelis-loewii Degen (sect. Acrocentron, Asteraceae), collected in Bulgaria was evaluated by GC-MS. The main components of the oil were β-caryophyllene (23.2%), germacrene D (13.7%) and caryophyllene oxide (12.4%). Furthermore, a complete literature review on the composition of the essential oils of all the other taxa of Centaurea, belonging to section Acrocentron, studied so far, was performed and the chemotaxonomical variations in the composition of the essential oils is discussed.

Chemical composition of the essential oils of Centaurea tomentella Hand.-Mazz. and C. haussknechtii Boiss. (Asteraceae) collected wild in Turkey and …

2018

In the present study the chemical composition of the essential oils from aerial parts of Centaurea tomentella Hand.-Mazz. and C. haussknechtii Boiss. collected in Turkey was evaluated by GC and GC-MS. The main components of C. tomentella L. were hexadecanoic acid (19.7%), caryophyllene oxide (6.6%) and spathulenol (4.8%) whereas C. haussknechtii was rich in hexadecanoic acid (26.2%), (Z,Z)-9,12-octadecadienoic acid (19.3%), heptacosane (5.3%) and nonacosane (5.1%). Antibacterial and antifungal activities against some microorganisms infesting historical art craft, were also determined.

Comparative investigation of the pollen morphology of Centaurea parlatoris gr. (sect. Dissectae, Compositae) in Sicily

2009

Comparative study of the isozyme variation of genus Centaurea in Sicily and South Italy

2010

Isozyme investigation on some taxa of Mediterranean Centaurea (Compositae)

2009

Genetic variation patterns in some groups of Centaurea (Asteraceae) in Italy

2012

In the current work the data of the isozyme analysis of all the twenty studied Italian Centaurea taxa were compared. They belong to Centaurea parlatoris, C. cineraria, C. tenorei and C. jacea groups. The following parameters of the genetic variability were considered: the total number of the alleles, the mean number of alleles per locus (A), the mean percentage of polymorphic loci (P95), the expected heterozygosity (He) that is a measure of the intra-population diversity, the Wright’s fixation index (F) and inbreeding coefficient (FIS) that are measures for the deviation from the Hardy-Weinberg equilibrium. The present study contributes to insight some aspects of the genetic diversity relat…

Plant Conservation Centres in Sicily: The ‘Valle Maria’ Regional Centre (Godrano, Palermo) and the case study of the rare Centaurea erycina (Asterace…

2017

The role of the ‘Valle Maria’ Regional Centre and its activity in plant conservation thank to the collaboration with the University of Palermo, Dept. STEBICEF is discussed. The case study on propagation of Centaurea erycina, a narrow Sicilian endemic is presented.