Understanding the bioactivity of plant tannins: developments in analysis methods and structure-activity studies

Tannins, typically segregated into two major groups, the hydrolyzable tannins (HTs) and the proanthocyanidins (PAs), are plant polyphenolic secondary metabolites found throughout the plant kingdom. On one hand, tannins may cause harmful nutritional effects on herbivores, for example insects, and hence they work as plants’ defense against plant-eating animals. On the other hand, they may affect positively some herbivores, such as mammals, for example by their antioxidant, antimicrobial, anti-inflammatory or anticarcinogenic activities. This thesis focuses on understanding the bioactivity of plant tannins, their anthelmintic properties and the tools used for the qualitative and quantitative analysis of this endless source of structural diversity. The first part of the experimental work focused on the development of ultra-high performance liquid chromatography−tandem mass spectrometry (UHPLC-MS/MS) based methods for the rapid fingerprint analysis of bioactive polyphenols, especially tannins. In the second part of the experimental work the in vitro activity of isolated and purified HTs and their hydrolysis product, gallic acid, was tested against egg hatching and larval motility of two larval developmental stages, L1 and L2, of a common ruminant gastrointestinal parasite, Haemonchus contortus. The results indicated clear relationships between the HT structure and the anthelmintic activity. The activity of the studied compounds depended on many structural features, including size, functional groups present in the structure, and the structural rigidness. To further understand tannin bioactivity on a molecular level, the interaction between bovine serum albumin (BSA), and seven HTs and epigallocatechin gallate was examined. The objective was to define the effect of pH on the formation on tannin–protein complexes and to evaluate the stability of the formed complexes by gel electrophoresis and MALDI-TOF-MS. The results indicated that more basic pH values had a stabilizing effect on the tannin–protein complexes and that the tannin oxidative activity was directly linked with their tendency to form covalently stabilized complexes with BSA at increased pH.

Maintenance and development of supplier relationships in an environment of irregular demand

The main target of the study was to find ideas for maintenance and development of supplier relations in irregular business environment. The other aim was to find out the suppliers’ opinions concerning the case company and the relationship between the companies. The study was conducted by using both qualitative and quantitative research methods. A mail survey was used to find out supplier opinions and an interview to find out suppliers’ ideas for relationship maintenance and development. It was found out that the use of relational elements is essential in the relationship maintenance in an irregular environment. In development of supplier relations the company should make better use of its suppliers’ potential, assure better flow of information and utilize the possibilities of Supplier Relationship Management.

Age and size structure of gap-dynamic, old-growth boreal forest stands in Newfoundland

[Abstract]

Cost information in engineering design -Potentials and limitations of activity-based costing

The purpose of this thesis is to analyse activity-based costing (ABC) and possible modified versions ofit in engineering design context. The design engineers need cost information attheir decision-making level and the cost information should also have a strong future orientation. These demands are high because traditional management accounting has concentrated on the direct actual costs of the products. However, cost accounting has progressed as ABC was introduced late 1980s and adopted widely bycompanies in the 1990s. The ABC has been a success, but it has gained also criticism. In some cases the ambitious ABC systems have become too complex to build,use and update. This study can be called an action-oriented case study with some normative features. In this thesis theoretical concepts are assessed and allowed to unfold gradually through interaction with data from three cases. The theoretical starting points are ABC and theory of engineering design process (chapter2). Concepts and research results from these theoretical approaches are summarized in two hypotheses (chapter 2.3). The hypotheses are analysed with two cases (chapter 3). After the two case analyses, the ABC part is extended to cover alsoother modern cost accounting methods, e.g. process costing and feature costing (chapter 4.1). The ideas from this second theoretical part are operationalized with the third case (chapter 4.2). The knowledge from the theory and three cases is summarized in the created framework (chapter 4.3). With the created frameworkit is possible to analyse ABC and its modifications in the engineering design context. The framework collects the factors that guide the choice of the costing method to be used in engineering design. It also illuminates the contents of various ABC-related costing methods. However, the framework needs to be further tested. On the basis of the three cases it can be said that ABC should be used cautiously when formulating cost information for engineering design. It is suitable when the manufacturing can be considered simple, or when the design engineers are not cost conscious, and in the beginning of the design process when doing adaptive or variant design. If the design engineers need cost information for the embodiment or detailed design, or if manufacturing can be considered complex, or when design engineers are cost conscious, the ABC has to be always evaluated critically.

Delivery Reliability: Timely and Quantitative Accuracy in a Forest Industry Company

The primary objective of this thesis was to research delivery reliability of mill business unit of a forest industry company, especially timely and quantitative accuracy of sales orders. Delivery reliability is an important factor of customer satisfaction, which has a great influence for success of a company. The secondary objective was to find out reasons for possible problems of delivery reliability and give propositions for improvable performances. The empirical part of the thesis based on reporting database of the forest industry company’s ERP-software and detailed information of the mill system. The delivery reliability results of the mill business unit were compared to delivery reliability of similar mill business unit inside the forest industry company. The research results expressed problems in the supply chain. The delivery reliability reporting should be also developed further. This would advance delivery reliability monitoring. The improvement propositions of the thesis were logistic operation mode estimation, particular benchmarking of the compared mill business unit and more detailed survey on production delivery reliability.

The Effects of Some Furnish and Paper Structure Related Factors on Wet Web Tensile and Relaxation Characteristics

The objective of this thesis was to identify the effects of different factors on the tension and tension relaxation of wet paper web after high-speed straining. The study was motivated by the plausible connection between wet web mechanical properties and wet web runnability on paper machines shown by previous studies. The mechanical properties of wet paper were examined using a fast tensile test rig with a strain rate of 1000%/s. Most of the tests were carried out with laboratory handsheets, but samples from a pilot paper machine were also used. The tension relaxation of paper was evaluated as the tension remaining after 0.475 s of relaxation (residual tension). The tensile and relaxation properties of wet webs were found to be strongly dependent on the quality and amount of fines. With low fines content, the tensile strength and residual tension of wet paper was mainly determined by the mechanical interactions between fibres at their contact points. As the fines strengthen the mechanical interaction in the network, the fibre properties also become important. Fibre deformations caused by the mechanical treatment of pulp were shown to reduce the mechanical properties of both dry and wet paper. However, the effect was significantly higher for wet paper. An increase of filler content from 10% to 25% greatly reduced the tensile strength of dry paper, but did not significantly impair wet web tensile strength or residual tension. Increased filler content in wet web was shown to increase the dryness of the wet web after the press section, which partly compensates for the reduction of fibrous material in the web. It is also presumable that fillers increase entanglement friction between fibres, which is beneficial for wet web strength. Different contaminants present in white water during sheet formation resulted in lowered surface tension and increased dryness after wet pressing. The addition of different contaminants reduced the tensile strength of the dry paper. The reduction of dry paper tensile strength could not be explained by the reduced surface tension, but rather on the tendency of different contaminants to interfere with the inter-fibre bonding. Additionally, wet web strength was not affected by the changes in the surface tension of white water or possible changes in the hydrophilicity of fibres caused by the addition of different contaminants. The spraying of different polymers on wet paper before wet pressing had a significant effect on both dry and wet web tensile strength, whereas wet web elastic modulus and residual tension were basically not affected. We suggest that the increase of dry and wet paper strength could be affected by the molecular level interactions between these chemicals and fibres. The most significant increases in dry and wet paper strength were achieved with a dual application of anionic and cationic polymers. Furthermore, selectively adding papermaking chemicals to different fibre fractions (as opposed to adding chemicals to the whole pulp) improved the wet web mechanical properties and the drainage of the pulp suspension.

Emancipating and developing learning activity: Systemic intervention and re-instrumentation in higher education.

The central theme of this thesis is the emancipation and further development of learning activity in higher education in the context of the ongoing digital transformation of our societies. It was developed in response to the highly problematic mainstream approach to digital re-instrumentation of teaching and studying practises in contemporary higher education. The mainstream approach is largely based on centralisation, standardisation, commoditisation, and commercialisation, while re-producing the general patterns of control, responsibility, and dependence that are characteristic for activity systems of schooling. Whereas much of educational research and development focuses on the optimisation and fine-tuning of schooling, the overall inquiry that is underlying this thesis has been carried out from an explicitly critical position and within a framework of action science. It thus conceptualises learning activity in higher education not only as an object of inquiry but also as an object to engage with and to intervene into from a perspective of intentional change. The knowledge-constituting interest of this type of inquiry can be tentatively described as a combination of heuristic-instrumental (guidelines for contextualised action and intervention), practical-phronetic (deliberation of value-rational aspects of means and ends), and developmental-emancipatory (deliberation of issues of power, self-determination, and growth) aspects. Its goal is the production of orientation knowledge for educational practise. The thesis provides an analysis, argumentation, and normative claim on why the development of learning activity should be turned into an object of individual|collective inquiry and intentional change in higher education, and why the current state of affairs in higher education actually impedes such a development. It argues for a decisive shift of attention to the intentional emancipation and further development of learning activity as an important cultural instrument for human (self-)production within the digital transformation. The thesis also attempts an in-depth exploration of what type of methodological rationale can actually be applied to an object of inquiry (developing learning activity) that is at the same time conceptualised as an object of intentional change within the ongoing digital transformation. The result of this retrospective reflection is the formulation of “optimally incomplete” guidelines for educational R&D practise that shares the practicalphronetic (value related) and developmental-emancipatory (power related) orientations that had been driving the overall inquiry. In addition, the thesis formulates the instrumental-heuristic knowledge claim that the conceptual instruments that were adapted and validated in the context of a series of intervention studies provide means to effectively intervene into existing practise in higher education to support the necessary development of (increasingly emancipated) networked learning activity. It suggests that digital networked instruments (tools and services) generally should be considered and treated as transient elements within critical systemic intervention research in higher education. It further argues for the predominant use of loosely-coupled, digital networked instruments that allow for individual|collective ownership, control, (co-)production, and re-use in other contexts and for other purposes. Since the range of digital instrumentation options is continuously expanding and currently shows no signs of an imminent slow-down or consolidation, individual and collective exploration and experimentation of this realm needs to be systematically incorporated into higher education practise.

Qualitative Characteristics and Quantitative Measures of Solution's Reliability in Discrete Optimization: Traditional Analytical Approaches, Innovative Computational Methods and Applicability

The purpose of this thesis is twofold. The first and major part is devoted to sensitivity analysis of various discrete optimization problems while the second part addresses methods applied for calculating measures of solution stability and solving multicriteria discrete optimization problems. Despite numerous approaches to stability analysis of discrete optimization problems two major directions can be single out: quantitative and qualitative. Qualitative sensitivity analysis is conducted for multicriteria discrete optimization problems with minisum, minimax and minimin partial criteria. The main results obtained here are necessary and sufficient conditions for different stability types of optimal solutions (or a set of optimal solutions) of the considered problems. Within the framework of quantitative direction various measures of solution stability are investigated. A formula for a quantitative characteristic called stability radius is obtained for the generalized equilibrium situation invariant to changes of game parameters in the case of the H¨older metric. Quality of the problem solution can also be described in terms of robustness analysis. In this work the concepts of accuracy and robustness tolerances are presented for a strategic game with a finite number of players where initial coefficients (costs) of linear payoff functions are subject to perturbations. Investigation of stability radius also aims to devise methods for its calculation. A new metaheuristic approach is derived for calculation of stability radius of an optimal solution to the shortest path problem. The main advantage of the developed method is that it can be potentially applicable for calculating stability radii of NP-hard problems. The last chapter of the thesis focuses on deriving innovative methods based on interactive optimization approach for solving multicriteria combinatorial optimization problems. The key idea of the proposed approach is to utilize a parameterized achievement scalarizing function for solution calculation and to direct interactive procedure by changing weighting coefficients of this function. In order to illustrate the introduced ideas a decision making process is simulated for three objective median location problem. The concepts, models, and ideas collected and analyzed in this thesis create a good and relevant grounds for developing more complicated and integrated models of postoptimal analysis and solving the most computationally challenging problems related to it.

Formal development and quantitative verification of dependable systems

-

Dynamical and Chemical Structure of Galactic Halos

This doctoral dissertation presents studies of the formation and evolution of galaxies, through observations and simulations of galactic halos. The halo is the component of galaxies which hosts some of the oldest objects we know of in the cosmos; it is where clues to the history of galaxies are found, for example, by how the chemical structure is related to the dynamics of objects in the halo. The dynamical and chemical structure of halos, both in the Milky Way’s own halo, and in two elliptical galaxies, is the underlying theme in the research. I focus on the density falloff and chemistry of the two external halos, and on the dynamics, density falloff, and chemistry of the Milky Way halo. I first study galactic halos via computer simulations, to test the long- term stability of an anomalous feature recently found in kinematics of the Milky Way’s metal-poor stellar halo. I find that the feature is transient, making its origin unclear. I use a second set of simulations to test if an initially strong relation between the dynamics and chemistry of halo glob-ular clusters in a Milky Way-type galaxy is affected by a merging satellite galaxy, and find that the relation remains strong despite a merger in which the satellite is a third of the mass of the host galaxy. From simulations, I move to observing halos in nearby galaxies, a challenging procedure as most of the light from galaxies comes from the disk and bulge components as opposed to the halo. I use Hubble Space Tele scope observations of the halo of the galaxy M87 and, comparing to similar observations of NGC 5128, find that the chemical structure of the inner halo is similar for both of these giant elliptical galaxies. I use Very Large Telescope observations of the outer halo of NGC 5128 (Centaurus A) and, because of the difficultly in resolving dim extragalac- tic stellar halo populations, I introduce a new technique to subtract the contaminating background galaxies. A transition from a metal-rich stellar halo to a metal-poor has previously been discovered in two different types of galaxies, the disk galaxy M31 and the classic elliptical NGC 3379. Unexpectedly, I discover in this third type of galaxy, the merger remnant NGC 5128, that the density of metal-rich and metal-poor halo stars falls at the same rate within the galactocentric radii of 8 − 65 kpc, the limit of our observations. This thesis presents new results which open opportunities for future investigations.

From genotype to phenotype : diversity and population structure of Flavobacterium psychrophilum

Flavobacterium psychrophilum is the etiological agent of bacterial cold-water disease (BCWD) causing high fish mortalities and significant economic losses to the freshwater salmonid aquaculture industry around the world. Today BCWD outbreaks are mainly treated with environmentally hazardous antimicrobial agents and alternative preventative measures are urgently needed in order to ensure the well-being of animals and the sustainability of aquaculture. The diversity of pathogenic bacteria challenges the development of universal control strategies and in many cases the pathogen population structure, i.e. the total genetic diversity of the species must be taken into account. This work integrates the tools of modern molecular biology and conventional phenotypic microbiology to gain knowledge about the diversity and population structure of F. psychrophilum. The present work includes genetic characterization of a large collection of isolates collected from diverse origins and years, from aquaculture in a whole region including different countries, and provides the first international validation of a universal multilocus sequence typing (MLST) approach for unambiguous genetic typing of F. psychrophilum. Population structure analyses showed that the global F. psychrophilum population is subdivided into pathogenic species-specific clones, of which one particular genetic lineage, clonal complex CC-ST2, has been responsible for the majority of BCWD outbreaks in rainbow trout (Oncorhynchus mykiss) in European aquaculture facilities over several decades. Genotypic and phenotypic population heterogeneity affecting antimicrobial resistance in F. psychrophilum within BCWD outbreaks was discovered. Specific genotypes were associated with severe infections in farmed rainbow trout and Atlantic salmon (Salmo salar), and in addition to high adherence, antimicrobial resistance was strongly associated with outbreak strains. The study brought additional support for the hypothesis of an epidemic F. psychrophilum population structure, where recombination is an important force for the generation and maintenance of genetic diversity, and a significant contribution towards mapping the genetic diversity of this important fish pathogen. Evidence indicating dissemination of virulent strains with commercial movement of fish and fish products was strengthened.