Relative asymptotics for orthogonal matrix polynomials with respect to a perturbed matrix measure on the unit circle

19 pages, no figures.-- MSC2000 codes: 42C05, 47A56.MR#: MR1970413 (2004b:42058)Zbl#: Zbl 1047.42021Given a positive definite matrix measure Ω supported on the unit circle T, then main purpose of this paper is to study the asymptotic behavior of L_n(\tilde{\Omega}) L_n(\Omega) -1} and \Phi_n(z, \tilde{\Omega}) \Phi_n(z, \tilde{\Omega}) -1} where $\tilde{\Omega}(z) = \Omega(z) + M \delta ( z - w)$, $1$, M is a positive definite matrix and δ is the Dirac matrix measure. Here, Ln(·) means the leading coefficient of the orthonormal matrix polynomials Φn(z; •).Finally, we deduce the asymptotic behavior of $\Phi_n(omega, \tilde{\Omega}) \Phi_n(omega, \Omega)$ in the case when M=I.The work of the second author was supported by Dirección General de Enseñanza Superior (DGES) of Spain under grant PB96-0120-C03-01 and INTAS Project INTAS93-0219 Ext.Publicad

Mycorrhization of fagaceae forests within mediterranean ecosystems

Mediterranean Fagaceae forests are valuable due to their ecological and socioeconomic aspects. Some profitable plant species, such as Castanea (timber and chestnut), Quercus (timber and cork), and Fagus (timber), encounter in this habitat the excellent edaphoclimatic conditions to develop. All Fagaceae plants are commonly associated to ECM fungal species, which are found in these forests in quite stable communities, mainly enriched in Russulaceae and Telephoraceae species. Currently, the Mediterranean Basin is considered as one of the global biodiversity hotspots, since many of their endemic plant species are not found elsewhere and are now under threat. Due to climate changing and introduction of disease agents, Fagaceae forests are facing an adaptation challenge to both biotic and abiotic threats. Although ECM communities are highly disturbed by climate factors and tree disease incidence, they could play an important role in increasing water availability to the plant and also improving plant tree defense against pathogens. Recent advances, namely, on genomics and transcriptomics, are providing tools for increasing the understanding of Fagaceae mycorrhization process and stress responses to biotic and abiotic stresses. Such studies can provide new information for the implementation of the most adequate management policies for protecting threaten Mediterranean forests.info:eu-repo/semantics/publishedVersio

Policing Migration : Described and Observed Cooperation Experiences of Police and Border Guards in the Baltic Sea Area

“Collaboration” is generally portrayed as being beneficial to intelligence and operational police work, even if previous collaborative research shows that conflicts are common between authorities who are supposed to cooperate. The present study focuses on how officers collaborate in their day-to-day management of borderguarding, taking into consideration the different social and cultural backgrounds of the project participants. To these ends, this qualitative, ethnographically study is based on empirical material gathered from interviews, field observation sessions with officers working at the Baltic Sea border agencies and documents. The findings suggest that, although collaboration is burdened with bureaucratic difficulties, there is a common understanding of purpose among the project participants. These border officers’ common declared their objective is to fight criminality and createa safer Europe. However, the participants possessing different organizational and cultural backgrounds have to adapt to adopta common language (in officers’ terms EU-English), common schemes of categorizing (inside-outside distinctions), and develop a sense of trust and identity. Collaboration is claimed by the informants, and is best achieved through getting involved ineveryday practices. They worked side by side, and spent free time together rather than following bureaucratic rules and regulations.Definitions of successful intelligence and operational police wor