867 resultados para Availability and efficiency


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The objective of this thesis was to study the response mechanisms of grapevine to Fe-deficiency and to potential Fe chlorosis prevention strategies. The results show that the presence of bicarbonate in the nutrient solution shifted the activity of PEPC and TCA cycle enzymes and the accumulation/translocation of organic acids in roots of Fe-deprived plants. The rootstock 140 Ruggeri displayed a typical behavior of calcicole plants under bicarbonate stress. The Fe chlorosis susceptible rootstock 101-14 reacted to a prolonged Fe-deficiency reducing the root activity of PEPC and MDH. Noteworthy, it accumulates high levels of citric acid in roots, indicating a low capacity to utilizing, transporting and/or exudating organic acids into the rhizosfere. In contrast, 110 Richter rootstock is capable to maintain an active metabolism of organic acids in roots, accumulating them to a lesser extent than 101-14. Similarly to 101-14, SO4 genotype displays a strong decrease of mechanisms associated to Fe chlorosis tolerance (PEPC and MDH enzymes). Nevertheless it is able to avoid excessive accumulation of citric acid in roots, similar as 110 Richter rootstock. Intercropping with Festuca rubra increased leaf chlorophyll content and net photosynthesis. In addition, intercropping reduces the activity of PEPC in roots, similary to Fe-chelate supply. Applications of NH4+ with nitrification inhibitor prevents efficiently Fe-deficiency, increases chlorophyll content, and induces similar root biochemical responses as Fe-EDDHA. Without the addition of nitrification inhibitors, the effectiveness of NH4+ supply on Fe chlorosis prevention resulted significantly lower. The aspects intertwined in this investigation highlight the complexity of Fe physiology and the fine metabolic tuning of grapevine genotypes to Fe availability and soil-related environmental factors. The experimental evidences reveal the need to carry out future researches on Fe nutrition maintaining a continous flow of knowledge between theoretical and agronomical perspectives for fully supporting the efforts devoted to convert science into practice.

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The objective of this study is to provide empirical evidence on how ownership structure and owner’s identity affect performance, in the banking industry by using a panel of Indonesia banks over the period 2000–2009. Firstly, we analysed the impact of the presence of multiple blockholders on bank ownership structure and performance. Building on multiple agency and principal-principal theories, we investigated whether the presence and shares dispersion across blockholders with different identities (i.e. central and regional government; families; foreign banks and financial institutions) affected bank performance, in terms of profitability and efficiency. We found that the number of blockholders has a negative effect on banks’ performance, while blockholders’ concentration has a positive effect. Moreover, we observed that the dispersion of ownership across different types of blockholders has a negative effect on banks’ performance. We interpret such results as evidence that, when heterogeneous blockholders are present, the disadvantage from conflicts of interests between blockholders seems to outweigh the advantage of the increase in additional monitoring by additional blockholder. Secondly, we conducted a joint analysis of the static, selection, and dynamic effects of different types of ownership on banks’ performance. We found that regional banks and foreign banks have a higher profitability and efficiency as compared to domestic private banks. In the short-run, foreign acquisitions and domestic M&As reduce the level of overhead costs, while in the long-run they increase the Net Interest Margin (NIM). Further, we analysed NIM determinants, to asses the impact of ownership on bank business orientation. Our findings lend support to our prediction that the NIM determinants differs accordingly to the type of bank ownership. We also observed that banks that experienced changes in ownership, such as foreign-acquired banks, manifest different interest margin determinants with respect to domestic or foreign banks that did not experience ownership rearrangements.

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This research focuses on taxonomy, phylogeny and reproductive ecology of Gentiana lutea. L.. Taxonomic analysis is a critical step in botanical studies, as it is necessary to recognize taxonomical unit. Herbarium specimens were observed to assess the reliability of several subspecies-diagnostic characters. The analysis of G. lutea genetic variability and the comparison with that of the other species of sect. Gentiana were performed to elucidate phylogenetic relationships among G. lutea subspecies and to propose a phylogenetic hypothesis for the evolution and the colonization dynamics of the section. Appropriate scientific information is critical for the assessment of species conservation status and for effective management plans. I carried out field work on five natural populations and performed laboratory analyses on specific critical aspects, with special regard to G. lutea breeding system and type and efficiency of plant-pollinator system. Bracts length is a reliable character to identify subsp. vardjanii, however it is not exclusive, hence to clearly identify subsp. vardjanii, other traits have to be considered. The phylogenetic hypotheses obtained from nuclear and chloroplast data are not congruent. Nuclear markers show a monophyly of sect. Gentiana, a strongly species identity of G. lutea and clear genetic identity of subsp. vardjanii. The little information emerging from plastid markers indicate a weak signal of hybridization and incomplete sorting of ancestral lineages. G. lutea shows a striking variation in intra-floral dichogamy probably evolved to reduce pollen-stigma interference. Although the species is partially self-compatible, pollen vectors are necessary for a successful reproduction, and moreover it shows a strong inbreeding depression. G. lutea is a generalist species: within its spectrum of visitors is possible to recognize "nectar thieves" and pollinators with sedentary or dynamic behaviour. Pollen limitation is frequent and it could be mainly explained by poor pollen quality.

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The fall of the Berlin Wall opened the way for a reform path – the transition process – which accompanied ten former Socialist countries in Central and South Eastern Europe to knock at the EU doors. By the way, at the time of the EU membership several economic and structural weaknesses remained. A tendency towards convergence between the new Member States (NMS) and the EU average income level emerged, together with a spread of inequality at the sub-regional level, mainly driven by the backwardness of the agricultural and rural areas. Several progresses were made in evaluating the policies for rural areas, but a shared definition of rurality is still missing. Numerous indicators were calculated for assessing the effectiveness of the Common Agricultural Policy and Rural Development Policy. Previous analysis on the Central and Eastern European countries found that the characteristics of the most backward areas were insufficiently addressed by the policies enacted; the low data availability and accountability at a sub-regional level, and the deficiencies in institutional planning and implementation represented an obstacle for targeting policies and payments. The next pages aim at providing a basis for understanding the connections between the peculiarities of the transition process, the current development performance of NMS and the EU role, with particular attention to the agricultural and rural areas. Applying a mixed methodological approach (multivariate statistics, non-parametric methods, spatial econometrics), this study contributes to the identification of rural areas and to the analysis of the changes occurred during the EU membership in Hungary, assessing the effect of CAP introduction and its contribution to the convergence of the Hungarian agricultural and rural. The author believes that more targeted – and therefore efficient – policies for agricultural and rural areas require a deeper knowledge of their structural and dynamic characteristics.

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This work presents a comprehensive methodology for the reduction of analytical or numerical stochastic models characterized by uncertain input parameters or boundary conditions. The technique, based on the Polynomial Chaos Expansion (PCE) theory, represents a versatile solution to solve direct or inverse problems related to propagation of uncertainty. The potentiality of the methodology is assessed investigating different applicative contexts related to groundwater flow and transport scenarios, such as global sensitivity analysis, risk analysis and model calibration. This is achieved by implementing a numerical code, developed in the MATLAB environment, presented here in its main features and tested with literature examples. The procedure has been conceived under flexibility and efficiency criteria in order to ensure its adaptability to different fields of engineering; it has been applied to different case studies related to flow and transport in porous media. Each application is associated with innovative elements such as (i) new analytical formulations describing motion and displacement of non-Newtonian fluids in porous media, (ii) application of global sensitivity analysis to a high-complexity numerical model inspired by a real case of risk of radionuclide migration in the subsurface environment, and (iii) development of a novel sensitivity-based strategy for parameter calibration and experiment design in laboratory scale tracer transport.

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L’agricoltura si trova ad affrontare una diminuzione della disponibilità d’acqua ed una crescente domanda della produzione di cereali per scopi alimentari. Sono perciò necessarie strategie di coltivazione innovative per migliorare la produttività e nuovi genotipi migliorati nell'efficienza dell’uso delle risorse in condizioni di siccità. Questi rappresentano gli obietti principali del progetto “DROPS” (Drought tolerant yielding Plants) all’interno del quale ha avuto luogo il mio progetto di Dottorato. La mia attività di ricerca è stata svolta come segue: 1. Caratterizzazione molecolare di un panel di188 accessioni di frumento duro con marcatori SSR e DaRT; 2. Esperimenti in serra su 100 accessioni del panel per valutare la Water-Use Efficiency (WUE) in sei repliche secondo un Alpha Lattice design; 3. Prove sul campo, effettuate secondo un Alpha Lattice design, in due stagioni di crescita: a. 2010/11, valutazione di 100 accessioni presso l’Azienda sperimentale dell'Università di Cadriano (BO); b. 2011/12, valutazione del panel completo in 3 ambienti, con due diversi regimi irrigui In entrambi gli anni, abbiamo valutato caratteri agronomici correlati con il ciclo di sviluppo, la resa di granella e sue componenti, nonché diversi fattori ambientali e del suolo. Per quanto riguarda WUE, abbiamo trovato differenze altamente significative tra accessioni; inoltre, cinque accessioni hanno mostrato elevati valori di WUE e cinque accessioni valori molto bassi di WUE in tutte e sei le repliche. Gli esperimenti di campo nelle stagioni 2011 e 2012 hanno evidenziato differenze altamente significative tra le accessioni del panel per la maggior parte dei caratteri analizzati, confermando inoltre che il panel di fiorisce entro una settimana. L'esperimento del secondo anno ci ha permesso osservare un significativa interazione Genotipo X Ambiente. Questi risultati saranno integrati con ulteriori analisi QTL, per identificare regioni cromosomiche coinvolte nel controllo genetico dei caratteri di interesse e verificare la stabilità dei QTL in diversi ambienti.

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Until today, autogenic bone grafts from various donor regions represent the gold standard in the field of bone reconstruction, providing both osteoinductive and osteoconductive characteristics. However, due to low availability and a disequilibrium between supply and demand, the risk of disease transfer and morbidity, usually associated with autogeneic bone grafts, the development of biomimic materials with structural and chemical properties similar to those of natural bone have been extensively studied. So far,rnonly a few synthetic materials, so far, have met these criteria, displaying properties that allow an optimal bone reconstitution. Biosilica is formed enzymatically under physiological-relevant conditions (temperature and pH) via silicatein (silica protein), an enzyme that was isolated from siliceous sponges, cloned, and prepared in a recombinant way, retaining its catalytic activity. It is biocompatible, has some unique mechanical characteristics, and comprises significant osteoinductive activity.rnTo explore the application of biosilica in the fields of regenerative medicine,rnsilicatein was encapsulated, together with its substrate sodium metasilicate, into poly(D,L-lactide)/polyvinylpyrrolidone(PVP)-based microspheres, using w/o/wrnmethodology with solvent casting and termed Poly(D,L-lactide)-silicatein silicacontaining-microspheres [PLASSM]. Both silicatein encapsulation efficiency (40%) and catalytic activity retention upon polymer encapsulation were enhanced by addition of an essential pre-emulsifying step using PVP. Furthermore, the metabolic stability, cytoxicity as well as the kinetics of silicatein release from the PLASSM were studied under biomimetic conditions, using simulated body fluid. As a solid support for PLASSM, a polyvinylpyrrolidone/starch/Na2HPO4-based matrix (termed plastic-like filler matrix containing silicic acid [PMSA]) was developed and its chemical and physical properties determined. Moreover, due to the non-toxicity and bioinactivity of the PMSA, it is suggested that PMSA acts as osteoconductive material. Both components, PLASSM and PMSA, when added together, form arnbifunctional 2-component implant material, that is (i)non-toxic(biocompatible), (ii)moldable, (iii) self-hardening at a controlled and clinically suitable rate to allows a tight insertion into any bone defect (iv) biodegradable, (v)forms a porous material upon exposure to body biomimetic conditions, and (vi)displays both osteoinductive (silicatein)and osteoconductive (PMSA) properties.rnPreliminary in vivo experiments were carried out with rabbit femurs, by creatingrnartificial bone defects that were subsequently treated with the bifunctional 2-component implant material. After 9 weeks of implantation, both computed tomography (CT) and morphological analyses showed complete resorption of the implanted material, concurrent with complete bone regeneration. The given data can be considered as a significant contribution to the successful introduction of biosilica-based implants into the field of bone substitution surgery.

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This study investigates the changes in soil fertility due to the different aggregate breakdown mechanisms and it analyses their relationships in different soil-plant systems, using physical aggregates behavior and organic matter (OM) changes as indicators. Three case studies were investigated: i) an organic agricultural soil, where a combined method, aimed to couple aggregate stability to nutrients loss, were tested; ii) a soil biosequence, where OM chemical characterisation and fractionation of aggregates on the basis of their physical behaviour were coupled and iii) a soils sequence in different phytoclimatic conditions, where isotopic C signature of separated aggregates was analysed. In agricultural soils the proposed combined method allows to identify that the severity of aggregate breakdown affected the quantity of nutrients lost more than nutrients availability, and that P, K and Mg were the most susceptible elements to water abrasion, while C and N were mainly susceptible to wetting. In the studied Chestnut-Douglas fir biosequence, OM chemical properties affected the relative importance of OM direct and indirect mechanisms (i.e., organic and organic-metallic cements, respectively) involved in aggregate stability and nutrient losses: under Douglas fir, high presence of carboxylate groups enhanced OM-metal interactions and stabilised aggregates; whereas under Chestnut, OM directly acted and fresh, more C-rich OM was preserved. OM direct mechanism seemed to be more efficient in C preservation in aggregates. The 13C natural abundance approach showed that, according to phytoclimatic conditions, stable macroaggregates can form both around partially decomposed OM and by organic-mineral interactions. In topsoils, aggregate resistance enhanced 13C-rich OM preservation, but in subsoils C preservation was due to other mechanisms, likely OM-mineral interactions. The proposed combined approach seems to be useful in the understanding of C and nutrients fate relates to water stresses, and in future research it could provide new insights into the complexity of soil biophysical processes.

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Glukokortikoide (GCs) stellen wichtige Hormone in der Regulation der metabolischen Homöostase dar. Synthetische GCs, wie Dexamethasone (DEX), spielen eine essentielle Rolle in der Behandlung inflammatorischer Krankheiten. Jedoch sind unter einer Dexamethason-Therapie zahlreiche Nebenwirkungen bekannt, so z.B. auch die Entwicklung einer Hypertonie, in deren Pathogenese oxidativer Stress eine entscheidende Rolle spielt. Obwohl sich in den vergangenen Jahren zahlreiche Studien zum Ziel setzten die GC-induzierte Hypertonie (GC-HT) aufzuklären, sind die genauen Mechanismen bis heute unklar. Eine erhöhte Expression von NADPH Oxidasen (Nox) und eine Entkopplung der endothelialen NO Synthase (eNOS), die Hauptquellen reaktiver Sauerstoffspezies (ROS) im vaskulären System, tragen maßgeblich zur Pathogenese kardiovaskulärer Erkrankungen bei. Daher ist eine Beteiligung dieser Enzyme in GC-induziertem oxidativen Stress sehr wahrscheinlich. Folglich wurde die Hypothese aufgestellt, dass NADPH Oxidasen und eine entkoppelte eNOS die vielversprechendsten unter den zahlreichen involvierten pro- und anti-oxidativen Enzymen sind. Mit Fokus auf die oben genannten Systeme wurde in der vorliegenden Studie der Effekt von DEX mit Hilfe von in vivo (WKY Ratten) ebenso wie in vitro Experimenten (A7r5 und EA.hy 926 Zellen) untersucht. Dabei zeigte sich, dass Nox1, Nox4 und p22phox durch DEX unterschiedlich reguliert wurden. Nox1 wurde hoch-, Nox4 hingegen herunterreguliert, während p22phox unverändert blieb. Die Modufikation schien hierbei auf transkriptioneller und post-transkriptioneller Ebene stattzufinden. Durch die gegensätzliche Regulation von Nox1 und Nox4 bleibt die Nettowirkung der verschiedenen Nox Isoformen unklar. Immer mehr Studien bringen vaskulären oxidativen Stress mit der Pathogenese einer GC-HT in Zusammenhang, welche letztendlich zu einer verminderten Bioverfügbarkeit von Stickstoffmonoxid (NO) führt. Durch die eNOS produziertes NO stellt einen essentiellen Schutzfaktor der Blutgefäße dar. Eine verminderte NO-Bioverfügbarkeit könnte die Folge einer eNOS-Entkopplung darstellen, ausgelöst durch oxidativen Stress. Da die Verfügbarkeit von Tetrahydrobiopterin (BH4) entscheident ist für die Aktivität und enzymatische Kopplung der eNOS, beschäftigt sich die vorliegende Arbeit mit GC-induzierten Veränderungen in der BH4-Versorgung. Die Behandlung von EA.hy 926 Zellen mit DEX führte zu einer zeit- und konzentrationsabhängigen Herunterregulation von eNOS auf mRNA- und Proteinebene. Gleichzeitig wurde die Phosphorylierung an Serine1177 vermindert. Als maßgeblicher “Kopplungs-Schalter” kann BH4 endogen über zwei verschiedene Signalwege synthetisiert werden, welche durch die Enzyme GCH1 und DHFR reguliert werden. DEX führte zu einer zeit- und konzentrationsabhängigen Herunterregulation von BH4, BH2 und Biopterin, wobei ebenso das BH4 / BH2 -Verhältnis vermindert wurde. Beide Enzyme, GCH1 genauso wie DHFR, wurden auf mRNA- und Proteinebene herunterreguliert, was auf einen Effekt von GCs auf beide rnBH4-produzierenden Signalwege schließen lässt. Nach Behandlung mit DEX wurde die Produktion von NO in Endothelzellen maßgeblich vermindert. In ROS-Messungen zeigte sich eine Tendenz hin zu einer eNOS-Entkopplung, jedoch war es mit unserem experimentellen Aufbau nicht möglich, diese endgültig zu beweisen.rnZusammenfassend lässt sich sagen, dass die Behandlung mit GCs zu Veränderungen in beiden untersuchten Systemen, den NADPH Oxidasen ebenso wie dem eNOS-NO System, führte. DEX erhöhte die Expression von Nox1 in glatten Muskelzellen und reduzierte die Nox4-Expression in Endothelzellen. Gleichzeitig verminderte DEX die Verfügbarkeit von BH4 und inhibierte die Phosphorylierung / Aktivität von eNOS. Mithilfe weiterer Studien muss die endgültige Beteiligung von NADPH Oxidasen und einer eNOS-Entkopplung an oxidativem Stress in GC-HT abschließend aufgeklärt werden.rn

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This is the second part of a study investigating a model-based transient calibration process for diesel engines. The first part addressed the data requirements and data processing required for empirical transient emission and torque models. The current work focuses on modelling and optimization. The unexpected result of this investigation is that when trained on transient data, simple regression models perform better than more powerful methods such as neural networks or localized regression. This result has been attributed to extrapolation over data that have estimated rather than measured transient air-handling parameters. The challenges of detecting and preventing extrapolation using statistical methods that work well with steady-state data have been explained. The concept of constraining the distribution of statistical leverage relative to the distribution of the starting solution to prevent extrapolation during the optimization process has been proposed and demonstrated. Separate from the issue of extrapolation is preventing the search from being quasi-static. Second-order linear dynamic constraint models have been proposed to prevent the search from returning solutions that are feasible if each point were run at steady state, but which are unrealistic in a transient sense. Dynamic constraint models translate commanded parameters to actually achieved parameters that then feed into the transient emission and torque models. Combined model inaccuracies have been used to adjust the optimized solutions. To frame the optimization problem within reasonable dimensionality, the coefficients of commanded surfaces that approximate engine tables are adjusted during search iterations, each of which involves simulating the entire transient cycle. The resulting strategy, different from the corresponding manual calibration strategy and resulting in lower emissions and efficiency, is intended to improve rather than replace the manual calibration process.

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Mounting an immune response against pathogens incurs costs to organisms by its effects on important life-history traits, such as reproductive investment and survival. As shown recently, immune activation produces large amounts of reactive species and is suggested to induce oxidative stress. Sperm are highly susceptible to oxidative stress, which can negatively impact sperm function and ultimately male fertilizing efficiency. Here we address the question as to whether mounting an immune response affects sperm quality through the damaging effects of oxidative stress. It has been demonstrated recently in birds that carotenoid-based ornaments can be reliable signals of a male's ability to protect sperm from oxidative damage. In a full-factorial design, we immune-challenged great tit males while simultaneously increasing their vitamin E availability, and assessed the effect on sperm quality and oxidative damage. We conducted this experiment in a natural population and tested the males' response to the experimental treatment in relation to their carotenoid-based breast coloration, a condition-dependent trait. Immune activation induced a steeper decline in sperm swimming velocity, thus highlighting the potential costs of an induced immune response on sperm competitive ability and fertilizing efficiency. We found sperm oxidative damage to be negatively correlated with sperm swimming velocity. However, blood resistance to a free-radical attack (a measure of somatic antioxidant capacity) as well as plasma and sperm levels of oxidative damage (lipid peroxidation) remained unaffected, thus suggesting that the observed effect did not arise through oxidative stress. Towards the end of their breeding cycle, swimming velocity of sperm of more intensely colored males was higher, which has important implications for the evolution of mate choice and multiple mating in females because females may accrue both direct and indirect benefits by mating with males having better quality sperm.

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Vaccination with Echinococcus multilocularis 14-3-3 protein can protect mice against primary E. multilocularis infection. The present study investigated the efficacy and efficiency of the adjuvant muramyl dipeptide Gerbu, alone or together with recombinant 14-3-3 protein, to modulate the course of secondary E. multilocularis infection in C56BL/6 mice. The application of Gerbu alone already resulted in a parasite weight reduction when compared with infected control mice, while rec14-3-3 did not add to this effect. Immunological parameters were concurrently assessed with a mixed cell reaction including bone marrow-derived dendritic cells (BMDCs) together with lymph node cells from mice with or without immunisation and/or infection. While mice having received Gerbu adjuvant were found to highly proliferate in response to co-cultivation with 14-3-3-stimulated bone marrow dendritic cells, a sensitisation of BMDCs with vesicle fluid (VF) antigen lead to a striking decrease of the lymphoproliferative response in comparison to that of control mice, raising the hypothesis that immunosuppressive components may be part of this VF-antigen. Anti-14-3-3 antibody production was only found in those mice that had been previously 14-3-3-immunised, whereas all other only-infected mice failed to produce such antibodies. Conclusively, Gerbu adjuvant appears to directly generate a non-specific immune response that contributes to the control of the metacestode growth, putatively in association with a BMDC activity suppressed by components of the VF-antigen.

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The reconstruction of large bone defects after injury or tumor resection often requires the use of bone substitution. Artificial scaffolds based on synthetic biomaterials can overcome disadvantages of autologous bone grafts, like limited availability and donor side morbidity. Among them, scaffolds based on nanofibers offer great advantages. They mimic the extracellular matrix, can be used as a carrier for growth factors and allow the differentiation of human mesenchymal stem cells. Differentiation is triggered by a series of signaling processes, including integrin and bone morphogenetic protein (BMP), which act in a cooperative manner. The aim of this study was to analyze whether these processes can be remodeled in artificial poly-(l)-lactide acid (PLLA) based nanofiber scaffolds in vivo. Electrospun matrices composed of PLLA-collagen type I or BMP-2 incorporated PLLA-collagen type I were implanted in calvarial critical size defects in rats. Cranial CT-scans were taken 4, 8 and 12 weeks after implantation. Specimens obtained after euthanasia were processed for histology and immunostainings on osteocalcin, BMP-2 and Smad5. After implantation the scaffolds were inhomogeneously colonized and cells were only present in wrinkle- or channel-like structures. Ossification was detected only in focal areas of the scaffold. This was independent of whether BMP-2 was incorporated in the scaffold. However, cells that migrated into the scaffold showed an increased ratio of osteocalcin and Smad5 positive cells compared to empty defects. Furthermore, in case of BMP-2 incorporated PLLA-collagen type I scaffolds, 4 weeks after implantation approximately 40 % of the cells stained positive for BMP-2 indicating an autocrine process of the ingrown cells. These findings indicate that a cooperative effect between BMP-2 and collagen type I can be transferred to PLLA nanofibers and furthermore, that this effect is active in vivo. However, this had no effect on bone formation. The reason for this seems to be an unbalanced colonization of the scaffolds with cells, due to insufficient pore size.

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The main goal of this project was to identity whether an imported system of social policy can be suitable for a host country, and if not why not. Romanian social policy concerning the mentally disabled represents a paradoxical situation in that while social policy is designed to ensure both an institutional structure and a juridical environment, in practice it is far from successful. The central question which Ms. Ciumageanu asked therefore was whether this failure was due to systemic factors, or whether the problem lay in reworking an imported social policy system to meet local needs. She took a comparative approach, also considering both the Scandinavian model of social policy, particularly the Danish model which has been adopted in Romania, and the Hungarian system, which has inherited a similar universal welfare system and perpetuated it to some extent. In order to verify her hypothesis, she also studied the transformation of the welfare system in Great Britain, which meant a shift from state responsibility towards community care. In all these she concentrated on two major aspects: the structural design within the different countries and, at a micro level, the societal response. Following her analyses of the various in the other countries concerned, Ms. Ciumageanu concluded that the major differences lie first in the difference between the stages of policy design. Here Denmark is the most advanced and Romania the most backwards. Denmark has a fairly elaborate infrastructure, Britain a system with may gaps to bridge, and Hungary and Romania are struggling with severe difficulties owing both to the inherited structure and the limits imposed by an inadequate GDP. While in Denmark and Britain, mental patients are integrated into an elaborate system of care, designed and administered by the state (in Denmark) or communities (in Britain), in Hungary and Romania, the state designs and fails to implement the policy and community support is minimal, partly due to the lack of a fully developed civil society. At the micro level the differences are similar. While in Denmark and Britain there is a consensus about the roles of the state and of civil societies (although at different levels in the two countries, with the state being more supportive in Denmark), in Romania and to a considerable extent in Hungary, civil society tends to expect too much from the state, which in its turn is withdrawing faster from its social roles than from its economic ones, generating a gap between the welfare state and the market economy and disadvantaging the expected transition from a welfare state to a welfare society and, implicitly, the societal response towards those mentally disabled persons in it. On an intermediate level, the factors influencing social policy as a whole were much the same for Hungary and Romania. Economic factors include the accumulated economic resources of both state and citizens, and the inherited pattern of redistribution, as well as the infrastructure; institutional resources include the role of the state and the efficiency of the state bureaucracy, the strength and efficiency of the state apparatus, political stability and the complexity of political democratisation, the introduction of market institutions, the strength of civil society and civic sector institutions. From the standpoint of the societal response, some factors were common to all countries, particularly the historical context, the collective and institutional memories and established patterns of behaviour. In the specific case of Romania, general structural and environmental factors - industrialisation and forced urbanisation - have had a definite influence on family structure, values and behavioural patterns. The analysis of Romanian social policy revealed several causes for failure to date. The first was the instability of the policy and the failure to consider the structural network involved in developing it, rather than just the results obtained. The second was the failure to take into account the relationship between the individual and the group in all its aspects, followed by the lack of active assistance for prevention, re-socialisation or professional integration of persons with mental disabilities. Finally, the state fails to recognise its inability to support an expensive psychiatric enterprise and does not provide any incentive to the private sector. This creates tremendous social costs for both the state and the individual. NGOs working in the field in Romania have been somewhat more successful but are still limited by their lack of funding and personnel and the idea of a combined system is as yet utopian in the circumstances in the country.

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This project set out to investigate the effects of the recent massive social transitions in Eastern Europe on the everyday social lives of the inhabitants of three very different nations: Georgia, Russia and Hungary. It focused in particular on the availability and nature of the support networks available to three different segments of each of the societies (manual workers, students and entrepreneurs) and the impact of network participation on psychological and physical well-being. The group set four specific questions to investigate: the part played by individual psychological beliefs in the formation and maintenance of social networks and the consequent formation of trusting relations; the implication of the size and quality of these networks for mental health; the nature of the social groups inhabited by the respondents and the implication of their work schedule and daily routines on the maintenance of a social and family life; and an analysis of how cultures vary in their social networks and intimacy. Three different methods were used to examine social support and its implications: structured questionnaires, semi-structured short interviews and a media analysis of newspaper materials. The questionnaires were administered to 150 participants in each country, equally divided between students studying full time, manual workers employed in factories, and business people (small kiosk owners, whose work and life style differs considerably from that of the manual workers). The questionnaires investigated various predictors of social support including the locus of control, relationship beliefs, individualism-collectivism and egalitarianism, demographic variables (age, gender and occupation), social support, both in general and in relation to significant events that have occurred since the transition from communism. Those with an internal locus of control were more likely to report a higher level of social support, as were collectivists, while age too was a significant predictor, with younger respondents enjoying higher levels of support, regardless of the measures of support employed. Respondents across the cultures referred to a decline of social support and the group also found a direct correlation between social support and mental health outcomes. All 450 respondents were interviewed on their general responses to changes in their lives since the fall of communism and the effects of their work lives on their social lives and the home environment. The interviews revealed considerable variations in the way in which work-life offered opportunities for a broader social life and also provided a hindrance to the development of fulfilling relationships. Many of the work experiences discussed were culture specific, with work having a particularly negative impact on the social life of Russian entrepreneurs but being seen much more positively in Georgia. This may reflect the nature of support offered in a society as overall support levels were lowest in Russia, meaning that social support may be of particular importance there. The way in cultural values and norms about personal relationships are transmitted in a culture is a critical issue for social psychologists and the group examined newspaper articles in those newspapers read by the respondents in each of the three countries. These revealed a number of different themes. The concept of a divided society and its implications for personal relationships was clearest in Russian and Hungary, where widely-read newspapers dwelt on the contrast between "new Russians/Hungarians" and the older, poorer ones and extended considerable sympathy to those suffering from neglect in institutions. Magyar Nemzet, a paper widely read by Hungarian students reflects the generally more pessimistic tone about personal relationships in Russia and Hungary and gave a particularly detailed analysis of the implications this holds for human relations in a modern society. In Georgia, however, the tone of the newspapers is more positive, stressing greater social cohesion. Part of this cohesion is framed in the context of religion, with the church appealing to a broader egalitarianism, whereas in less egalitarian Hungary appeals by the Church are centred more on the nuclear family and its need for expansion in both size and influence. The division between the sexes was another prominent issue in Hungary and Russia, while the theme of generational conflict also emerged in Hungarian and Georgian papers, although with some understanding of "young people today". The team's original expectation that the different newspapers read by the different groups of respondents would present differing images of personal relationships was not fulfilled, as despite variations in style, they found little clear "ideological targeting" of any particular readership. They conclude that the vast majority of respondents recognised that the social transition from communism has had a significant impact on the well-being of social relationships and that this is a pertinent issue for all segments of society. While the group see the data collected as a source to be worked on for some time in the future, their initial impressions include the following. Social support is clearly an important concern across all three countries. All respondents (including the students) lament the time taken up by their heavy work schedules and value their social networks and family ties in particular. The level of social support differs across the countries investigated, with Georgian apparently enjoying significantly higher levels of social support. The analysis produced an image of a relatively cohesive and egalitarian society in which even the group most often seen as distant from the general population, business people, is supported by a strong social network. In contrast, the support networks available to the Russian respondents seem particularly weak and reflect a general sense of division and alienation within the culture as a whole. The implications of low levels of social support may vary across countries. While Russians reported the lowest level of mental health problems, the link between social support and mental health may be strongest in that country. In contrast, in Hungary it is the link between fatalism and mental health problems which is particularly strong, while in Georgia the strongest correlation was between mental health and marital quality, emphasising the significance of the marital relationship in that country.