2,477 research outputs found
Searching for emission-line galaxies: The UCM survey
We are carrying out a long-term project with the main purposes of finding and analyzing low metallicity galaxies. A very small number of very low metallicity galaxies is known up to now. However these ojbects are particularly interesting since they are excellent candidates to 'young galaxies' in evolutionary sense as POX186 (Kunth, Maurogordato & Vigroux, 1988). Since the interstellar matter in these objects is only weakly contaminated by stellar evolution, their study could provide valuable information about the primordial helium abundance and therefore it could place constraints on the different Big-Bang models. The instrumental set up of our survey is an objective-prism used with the Schmidt telescope at Calar Alto Observatory. By using hypersensitized IIIaF emulsion and RG630 filter low resolution spectra in the H alpha region of objects in a wide field is obtained (Rego et al. 1989, Zamorano et al. 1990). Surveys carried out in the past two decades at optical blue wavelengths have also produced large samples of emission-line galaxies (ELGs), for example MacAlpine & Willians 1981 and reference therein, Wasilewski 1983, Salzer and MacAlpine 1988, or Smith et al. 1976. Relying primarily on objective-prism plates taken in the blue, these surveys have found over 3000 blue/emission-line galaxies so far. A significant number of star-forming galaxies are missed by optical surveys in the blue because of their low-excitation spectra (MacAlpine and Willians 1981, Markarian et al. 1981 and references therein) or their low metallicity (Kunth and Sargent, 1986)
Reproductive phenology: Lauraceae family in the Brazilian Atlantic Forest.
Published in 8th EGU General Assembly 2011
Monitoring of reproductive phenological events of species of Myrtaceae in the Brazilian Atlantic Forest.
Published in 8th EGU General Assembly 2011
Atividades fenológicas de imbuia (Ocotea porosa (NEES ET MARTIUS ex NESS) em áreas de Floresta Ombrófila Mista, no Estado do Paraná.
1 CD-ROM
Positive leadership action framework: Simply doing good and doing well
This article presents the Positive Leadership Action Framework (PLAF) to structure Positive Leadership (PL). The novelty of the PLAF is that it incorporates the connections of PL to positive outcomes (financial and economic performance and social well-being) and organizational virtuousness. Also, it acknowledges its conditional nature on the virtues to achieve flourishing within the organization and society at large. We argue that the leader’s actions function as the engine for positive change within the organization, bridging the gap between individual virtues and organizational virtuousness and creating a feedback loop among both. To develop a positive organization, a leader needs to create positive assumptions among (and about) coworkers, positively impact the personal and professional development of employees, and balance positive formal and informal conditions at work. To do so, it is a sine qua non condition that the positive leader fosters his/her personal development by exercising the virtues and developing practical wisdom. In this way, the positive leader automatically provides followers with a vision of the final end towards the common good and achieves to set his/her organization on a pathway towards excellence
Construction of coherent states for physical algebraic systems
We construct a general state which is an eigenvector of the annihilation
operator of the Generalized Heisenberg Algebra. We show for several systems,
which are characterized by different energy spectra, that this general state
satisfies the minimal set of conditions required to obtain Klauder's minimal
coherent states.Comment: 15 pages, 3 figure
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