Knowledge flows in cluster organisations in Western Poland

Wydział Nauk Geograficznych i GeologicznychW rozprawie doktorskiej zrealizowano trzy główne cele: 1) teoretyczny, tj. konceptualizację zagadnienia przepływów wiedzy w organizacjach klastrowych na gruncie przestrzenno-ekonomicznym, 2) empiryczny: identyfikację uwarunkowań, form i mechanizmów tych przepływów w organizacjach w Polsce Zachodniej oraz 3) aplikacyjny: sformułowanie rekomendacji dla polityki regionalnej w zakresie możliwości i sposobów wspierania przepływów wiedzy w organizacjach klastrowych. Nowatorskie ujęcie tytułowego zagadnienia oparte zostało na dwóch nurtach: geografii relacyjnej (badanie regionalnego domknięcia transferu wiedzy z uczelni i jednostek otoczenia biznesu do firm oraz efektów rozlewania się wiedzy do otoczenia regionalnego), a także teorii interesariuszy (analiza przepływów wiedzy z punktu widzenia różnych aktorów). Badania terenowe przeprowadzane zostały z wykorzystaniem wywiadów pogłębionych, a w odniesieniu do dwóch studiów przypadku – wywiadów półstrukturyzowanych, a następnie metody analizy sieciowej. Pozwoliły one wyznaczyć najczęściej wykorzystywane przez firmy w organizacjach klastrowych sposoby pozyskiwania i rozpowszechniania nowej wiedzy (zarówno celowe, jak i spontaniczne). Podjęta została próba sformułowania modeli przepływów wiedzy w organizacjach klastrowych zawiązywanych w sposób oddolny i odgórny, co pozwoliło na przedstawienie zaleceń dla polityki klastrowej.In the doctoral dissertation three chief goals have been accomplished: (1) theoretical, or the conceptualisation of knowledge flows in cluster organisations in spatial-economic terms, (2) empirical, or the identification of the determinants, forms and mechanisms of those flows in organisations in Western Poland, and (3) application-oriented, or the formulation of recommendations for a regional policy concerning the possibilities and ways of supporting knowledge flows in cluster organisations. The novel approach to the title matter derived from two streams: relational geography (the study of the regional closure of the transfer of knowledge from schools and business environment units to firms, and the effects of knowledge spillover to the regional environment), and the stakeholder theory (an analysis of knowledge flows from the point of view of different actors). A field research was conducted using in-depth interviews or, in two case studies, semi-structured interviews, and was followed by a social network analysis. This allowed determining ways of obtaining and propagating new knowledge (both intentional and spontaneous) that firms in cluster organisations employed most frequently. The two models were proposed of knowledge flows depending on whether a cluster organisation was set up in a bottom-up or a top-down way, which allowed formulating recommendations for a cluster policy

Dimerization of the immunosuppressive peptide fragment of HLA-DR molecule enhances its potency

Abstract Our previous studies revealed that the nonapeptide fragment of HLA-DR molecule, located in the ␤ chain 164-172 with the VPRSGEVYT sequence, suppresses the immune responses. The sequence is located on the exposed molecule loop, therefore it may be involved in the interactions with other proteins. We suggested that the loop may serve as a functional epitope on the HLA class II surface for intermolecular binding, and that possible mechanism of biological action of the synthesized peptides is associated with interfering of adhesion of HLA class II molecules to their coreceptors. It has been postulated that oligomerization of the coreceptors is required for stable binding to class II HLA. Based on the crystal dimeric structure of HLA-DR molecules, we designed, and synthesized molecules able to induce the putative coreceptors dimerization. The synthesized series of compounds consisted of two VPRSGEVYT sequences linked through their C-termini by spacers of different length: (VPRSGEVYTG n ) 2 K-NH 2 (n = 4-6). The results demonstrate that the dimerization of the nonapeptide fragment of HLA-DR results in enhanced immunosuppressory properties

Copper(II) complexes of the imidazolinone herbicide imazapyr

The copper(II) complexes formed by the imidazolinone herbicide imazapyr [(±)-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)nicotinic acid] were studied in aqueous solution by potentiometric and spectroscopic techniques. Imazapyr acts as a chelating molecule and is effective over a wide pH range. The chelating set active in acidic media involves rather weak donors, namely the pyridine and imidazole nitrogens. In neutral media, the lactam site of the imidazolinone ring deprotonates and the ligand takes advantage of a rather basic nitrogen atom, which, assisted by the pyridine donor, yields stable complexes with five-coordination at the metal ion

Specific interactions of bovine and human beta-casomorphin-7 with Cu(II) ions

Complex formation between Cu(II) and human and bovine β-casomorphin heptapeptides, Tyr-Pro-Phe-Val-Glu-Pro-Ile and Tyr-Pro-Phe-Pro-Gly-Pro-Ile, respectively, was investigated by pH potentiometry and spectroscopic (CD, EPR and electronic absorption) techniques. The results showed the critical impact of Pro residues on the complex equilibria formed. The presence of the Pro residue at the second position leads to formation of very stable dimeric species in which two metal ions co-ordinate to N-terminal {NH2,C=O} binding sites of one peptide molecule and the deprotonated phenolic oxygen of the second ligand molecule. The presence of two additional hydrophobic residues on the C-terminal makes heptapeptide molecule much more effective ligand than its pentapeptide N-terminal fragment