A Simple Instrumentation Calibration Technique for Electrical Impedance Tomography (EIT) Using A 16-Electrode Phantom

A simple analog instrumentation for Electrical Impedance Tomography is developed and calibrated using the practical phantoms. A constant current injector consisting of a modified Howland voltage controlled current source fed by a voltage controlled oscillator is developed to inject a constant current to the phantom boundary. An instrumentation amplifier, 50 Hz notch filter and a narrow band pass filter are developed and used for signal conditioning. Practical biological phantoms are developed and the forward problem is studied to calibrate the EIT-instrumentation. An array of sixteen stainless steel electrodes is developed and placed inside the phantom tank filled with KCl solution. 1 mA, 50 kHz sinusoidal current is injected at the phantom boundary using adjacent current injection protocol. The differential potentials developed at the voltage electrodes are measured for sixteen current injections. Differential voltage signal is passed through an instrumentation amplifier and a filtering block and measured by a digital multimeter. A forward solver is developed using Finite Element Method in MATLAB7.0 for solving the EIT governing equation. Differential potentials are numerically calculated using the forward solver with a simulated current and bathing solution conductivity. Measured potential data is compared with the differential potentials calculated for calibrating the instrumentation to acquire the voltage data suitable for better image reconstruction.

Toiminta, valta ja kokemus organisaation muutoksessa : Tutkimus kolmesta suuryrityksestä

Action, Power and Experience in Organizational Change - A Study of Three Major Corporations This study explores change management and resistance to change as social activities and power displays through worker experiences in three major Finnish corporations. Two important sensitizing concepts were applied. Firstly, Richard Sennett's perspective on work in the new form of capitalism, and its shortcomings - the lack of commitment and freedom accompanied by the disruption to lifelong career planning and the feeling of job insecurity - offered a fruitful starting point for a critical study. Secondly, Michel Foucault's classical concept of power, treated as anecdotal, interactive and nonmeasurable, provided tools for analyzing change-enabling and resisting acts. The study bridges the gap between management and social sciences. The former have usually concentrated on leadership issues, best practices and goal attainment, while the latter have covered worker experiences, power relations and political conflicts. The study was motivated by three research questions. Firstly, why people resist or support changes in their work, work environment or organization, and the kind of analyses these behavioural choices are based on. Secondly, the kind of practical forms which support for, and resistance to change take, and how people choose the different ways of acting. Thirdly, how the people involved experience and describe their own subject position and actions in changing environments. The examination focuses on practical interpretations and action descriptions given by the members of three major Finnish business organizations. The empirical data was collected during a two-year period in the Finnish Post Corporation, the Finnish branch of Vattenfal Group, one of the leading European energy companies, and the Mehiläinen Group, the leading private medical service provider in Finland. It includes 154 non-structured thematic interviews and 309 biographies concentrating on personal experiences of change. All positions and organizational levels were represented. The analysis was conducted using the grounded theory method introduced by Straus and Corbin in three sequential phases, including open, axial and selective coding processes. As a result, there is a hierarchical structure of categories, which is summarized in the process model of change behaviour patterns. Key ingredients are past experiences and future expectations which lead to different change relations and behavioural roles. Ultimately, they contribute to strategic and tactical choices realized as both public and hidden forms of action. The same forms of action can be used in both supporting and resisting change, and there are no specific dividing lines either between employer and employee roles or between different hierarchical positions. In general, however, it is possible to conclude that strategic choices lead more often to public forms of action, whereas tactical choices result in hidden forms. The primary goal of the study was to provide knowledge which has practical applications in everyday business life, HR and change management. The results, therefore, are highly applicable to other organizations as well as to less change-dominated situations, whenever power relations and conflicting interests are present. A sociological thesis on classical business management issues can be of considerable value in revealing the crucial social processes behind behavioural patterns. Keywords: change management, organizational development, organizational resistance, resistance to change, change management, labor relations, organization, leadership

A Success Story or a Failure? : Representing the European Integration in the Curricula and Textbooks of Five Countries

The economic, political and social face of Europe has been changing rapidly in the past decades. These changes are unique in the history of Europe, but not without challenges for the nation states. The support for the European integration varies among the countries. In order to understand why certain developments or changes are perceived as threatening or as desired by different member countries, we must consider the social representations of the European integration on the national level: how the EU is represented to its citizens in media and in educational systems, particularly in the curricula and textbooks. The current study is concerned with the social representations of the European integration in the curricula and school textbooks in five European countries: France, Britain, Germany, Finland and Sweden. Besides that, the first volume of the common Franco-German history textbook was analyzed, since it has been seen as a model for a common European history textbook. As the collective representations, values and identities are dominantly mediated and imposed through media and educational systems, the national curricula and textbooks make an interesting starting point for the study of the European integration and of national and European identities. The social representations theory provides a comprehensive framework for the study of the European integration. By analyzing the curricula and history and civics textbooks of major educational publishers, the study aimed to demonstrate what is written on the European integration and how it is portrayed how the European integration is understood, made familiar and concretized in the educational context in the five European countries. To grasp the phenomenon of the European integration in the textbooks in its entirety, it was investigated from various perspectives. The two analysis methods of content analysis, the automatic analysis with ALCESTE and a more qualitative theory-driven content analysis, were carried out to give a more vivid and multifaceted picture of the object of the research. The analysis of the text was complemented with the analysis of visual material. Drawing on quantitative and qualitative methods, the contents, processes, visual images, transformations and structures of the social representations of European integration, as well as the communicative styles of the textbooks were examined. This study showed the divergent social representations of the European integration, anchored in the nation states, in the five member countries of the European Union. The social representations were constructed around different central core elements: French Europe in the French textbooks, Ambivalent Europe in the British textbooks, Influential and Unifying EU in the German textbooks, Enabling and Threatening EU in the Finnish textbooks, Sceptical EU in the Swedish textbooks and EU as a World Model in the Franco-German textbook. Some elements of the representations were shared by all countries such as peace and economic aspects of the European cooperation, whereas other elements of representations were found more frequently in some countries than in others, such as ideological, threatening or social components of the phenomenon European integration. The study also demonstrated the linkage between social representations of the EU and national and European identities. The findings of this study are applicable to the study of the European integration, to the study of education, as well as to the social representation theory.

Sulkeuman ja neuvottelun ehdoilla : asiantuntija-aseman rakentuminen työelämässä

Closure and negotiation constructing professional position in working life The aim of the thesis is to analyse how professional positions are constructed in working life. A professional position refers to a formal professional membership, but also to a position at a work site. Formal jurisdiction provides resources for supporting a position, but the relations, practices and processes at the work site strongly shape it as well. Professional membership includes two gates: obtaining a professional diploma and access to a professional post. The concept of a professional position is based on two sub-concepts: legitimation and authority. Legitimation is society-level jurisdiction over professioning. Legitimation can be claimed in legislation, in the public space and the media, and at the work site. Authority requires constructing professional work territories and practicing authority in work-related decision making processes. The thesis is based on five articles which deal with the following topics: gendered professional careers; organising professional work; the impact of the social and cultural backgrounds when striving for professional positions; and models of research work. The articles represent two types of sociological research: the structural approach with quantitative methodology and the approach of micro-social analysis with qualitative methodology. The first approach was suitable for analyzing professional career formation and its social and ethnic conditions. The second approach has been applied in the articles dealing with the organization of professional work and models of research work. I have combined and analysed the results of these studies under the theoretical frame of the professional position in working life. Legislation is the most powerful form of legitimation. Professional membership is strongly regulated in disciplines where a degree requirement is defined by law. In addition, closures related to social conditions still affect professional positions, but their character is loose and changing. The closures related to social conditions are based on many mutually overlapping principles: social, cultural and ethnic backgrounds and gender. Despite the closures, professional experts have to negotiate their positions, particularly when the situation in the work sites and society changes. Professional authority is reinforced at the organizational level by legislation; when the institutional status of a public sector professional organization is defined by law, it reinforces the professional position of the employees. In the business line of new media, the employees need to negotiate with the management, other professional groups and clients when striving for reinforce their professional position.

Regulating Food Consumption : Studies of change and variation in Europe

The role of people as buyers and eaters of food has changed significantly. From being protected by a paternalistic welfare state, people appear to be accorded more freedom and responsibility as individuals, where attention is redirected from the state towards market relations. Many have asserted that these changes are accompanied by fragmentation, individualisation, and privatisation, leading to individual uncertainty and lack of confidence. But empirical observations do not always confirm this, distrust is not necessarily growing and while responsibilities may change, the state still plays an active role. This dissertation explores changing relationships between states and markets, on the one hand, and ordinary people in their capacities as consumers and citizens, on the other. Do we see the emergence of new forms of regulation of food consumption? If so, what is the scope and what are the characteristics? Theories of regulation addressing questions about individualisation and self-governance are combined with a conceptualisation of consumption as processes of institutionalisation, involving daily routines, the division of labour between production and consumption, and the institutional field in which consumption is embedded. The analyses focus on the involvement of the state, food producers and scientific, first of all nutritional, expertise in regulating consumption, and on popular responses. Two periods come out as important, first when the ideas of “designing the good life” emerged, giving the state a very particular role in regulating food consumption, and, second, when this “designing” is replaced by ideas of choice and individual responsibility. One might say that “consumer choice” has become a mode of regulation. I use mainly historical studies from Norway to analyse the shifting role of the state in regulating food consumption, complemented with population surveys from six European countries to study how modernisation processes are associated with trust. The studies find that changing regulation is not only a question of societal or state vs individual responsibilities. Degrees of organisation and formalisation are important as well. While increasing organisation may represent discipline and abuses of power (including exploitation of consumer loyalty), organisation can also, to the consumer, provide higher predictability, systems to deal with malfeasance, and efficiency which may provide conditions for acting. The welfare state and the neo-liberal state have very different types of solutions. The welfare state solution is based on (national) egalitarianism, paternalism and discipline (of the market as well as households). Such solutions are still prominent in Norway. Individualisation and self-regulation may represent a regulatory response not only to a declining legitimacy of this kind of interventionism, but also increasing organisational complexity. This is reflected in large-scale re-regulation of markets as well as in relationships with households and consumers. Individualisation of responsibility is to the consumer not a matter of the number of choices that are presented on the shelves, but how choice as a form of consumer based involvement is institutionalised. It is recognition of people as “end-consumers”, as social actors, with systems of empowerment politically as well as via the provisioning system. ‘Consumer choice’ as a regulatory strategy includes not only communicative efforts to make people into “choosing consumers”, but also the provision of institutions which recognise consumer interests and agency. When this is lacking we find distrust as representing powerlessness. Individual responsibility-taking represents agency and is not always a matter of loyal support to shared goals, but involves protest and creativity. More informal (‘communitarian’) innovations may be an indication of that, where self-realisation is intimately combined with responsibility for social problems. But as solutions to counteract existing imbalances of power in the food market the impacts of such initiatives are probably more as part of consumer mobilisation and politicisation than as alternative provisioning.

Consent Practices and Biomedical Knowledge Production in Tissue Economies

The use of human tissue sample collections has become an important tool in biomedical research. The collection, use and distribution of human tissue samples, which include blood and diagnostic tissue samples, from which DNA can be extracted and analyzed has also become a major bio-political preoccupation, not only in national contexts, but also at the transnational level. The foundation of medical research rests on the relationship between the doctor and the research subject. This relationship is a social one, in that it is based on informed consent, privacy and autonomy, where research subjects are made aware of what they are getting involved in and are then able to make an informed decision as to whether or not to participate. Within the post-genomic era, however, our understanding of what constitutes informed consent, privacy and autonomy is changing in relation to the needs of researchers, but also as a reflection of policy aspirations. This reflects a change in the power relations between the rights of the individual in relation to the interests of science and society. Using the notions of tissue economies and biovalue (Waldby, 2002) this research explores the changing relationship between sources and users of samples in biomedical research by examining the contexts under which human tissue samples and the information that is extracted from them are acquired, circulated and exchanged in Finland. The research examines how individual rights, particularly informed consent, are being configured in relation to the production of scientific knowledge in tissue economies in Finland from the 1990s to the present. The research examines the production of biovalue through the organization of scientific knowledge production by examining the policy context of knowledge production as well as three case studies (Tampere Research Tissue Bank, Hereditary Non-polyposis Colorectal Cancer and the Finnish Genome Information Center) in which tissues are acquired, circulated and exchanged in Finland. The research shows how interpretations of informed consent have become divergent and the elements and processes that have contributed to these differences. This inquiry shows how the relationship between the interests of individuals is re-configured in relation to the interests of science and society. It indicates how the boundary between interpretations of informed consent, on the one hand, and social and scientific interests, on the other, are being re-drawn and that this process is underscored, in part, by the economic, commercial and preventive potential that research using tissue samples are believed to produce. This can be said to fundamentally challenge the western notion that the rights of the individual are absolute and inalienable within biomedical legislation.

Ultrastructure of Biofilms Formed by Bacteria from Industrial Processes

Microorganisms exist predominantly as sessile multispecies communities in natural habitats. Most bacterial species can form these matrix-enclosed microbial communities called biofilms. Biofilms occur in a wide range of environments, on every surface with sufficient moisture and nutrients, also on surfaces in industrial settings and engineered water systems. This unwanted biofilm formation on equipment surfaces is called biofouling. Biofouling can significantly decrease equipment performance and lifetime and cause contamination and impaired quality of the industrial product. In this thesis we studied bacterial adherence to abiotic surfaces by using coupons of stainless steel coated or not coated with fluoropolymer or diamond like carbon (DLC). As model organisms we used bacterial isolates from paper machines (Meiothermus silvanus, Pseudoxanthomonas taiwanensis and Deinococcus geothermalis) and also well characterised species isolated from medical implants (Staphylococcus epidermidis). We found that coating of steel surface with these materials reduced its tendency towards biofouling: Fluoropolymer and DLC coatings repelled all four biofilm formers on steel. We found great differences between bacterial species in their preference of surfaces to adhere as well as their ultrastructural details, like number and thickness of adhesion organelles they expressed. These details responded differently towards the different surfaces they adhered to. We further found that biofilms of D. geothermalis formed on titanium dioxide coated coupons of glass, steel and titanium, were effectively removed by photocatalytic action in response to irradiation at 360 nm. However, on non-coated glass or steel surfaces irradiation had no detectable effect on the amount of bacterial biomass. We showed that the adhesion organelles of bacteria on illuminated TiO2 coated coupons were complety destroyed whereas on non-coated coupons they looked intact when observed by microscope. Stainless steel is the most widely used material for industrial process equipments and surfaces. The results in this thesis showed that stainless steel is prone to biofouling by phylogenetically distant bacterial species and that coating of the steel may offer a tool for reduced biofouling of industrial equipment. Photocatalysis, on the other hand, is a potential technique for biofilm removal from surfaces in locations where high level of hygiene is required. Our study of natural biofilms on barley kernel surfaces showed that also there the microbes possessed adhesion organelles visible with electronmicroscope both before and after steeping. The microbial community of dry barley kernels turned into a dense biofilm covered with slimy extracellular polymeric substance (EPS) in the kernels after steeping in water. Steeping is the first step in malting. We also presented evidence showing that certain strains of Lactobacillus plantarum and Wickerhamomyces anomalus, when used as starter cultures in the steeping water, could enter the barley kernel and colonise the tissues of the barley kernel. By use of a starter culture it was possible to reduce the extensive production of EPS, which resulted in a faster filtration of the mash.

Augustine and the functions of concupiscence

This study analyses Augustine s concept of concupiscentia, or evil desire (together with two cognate terms, libido and cupiditas) in the context of his entire oeuvre. By the aid of systematic analysis, the concept and its development is explored in four distinct ways. It is claimed that Augustine used the concept of concupiscentia for several theological purposes, and the task of the study is to represent these distinct functions, and their connections to Augustine s general theological and philosophical convictions. The study opens with a survey on terminology. A general overview of the occurrences of the negatively connoted words for desire in Latin literature precedes a corresponding examination of Augustine s own works. In this introductory chapter it is shown that, despite certain preferences in the uses of the words, a sufficient degree of synonymy reigns so as to allow an analysis of the concept without tightly discriminating between the terms. The theological functions of concupiscentia with its distinct contexts are analysed in separate chapters. The function of concupiscentia as a divine punishment is explored first (Ch 3). It is seen how Augustine links together concupiscentia and ideas about divine justice, and finally suggests that in the inordinate, psychologically experienced sexual desire, the original theological disobedience of Adam and Eve can be perceived. Augustine was criticized for this solution already in his own times, and the analysis of the function of concupiscentia as a divine punishment ends in a discussion on the critical response of punitive concupiscentia by Julian of Aeclanum. Augustine also attached to concupiscentia another central theological function by viewing evil desire as an inward originating cause for all external evil actions. In the study, this function is analysed by surveying two formally distinct images of evil desire, i.e. as the root (radix) of all evil, and as a threefold (triplex) matrix of evil actions (Ch 4). Both of these images were based on a single verse of the Bible (1 Jn 2, 16 and 1 Tim 6, 10). This function of concupiscentia was formed both parallel to, and in answer to, Manichaean insights into concupiscentia. Being familiar with the traditional philosophical discussions on the nature and therapy of emotions, Augustine situated concupiscentia also into this context. It is acknowledged that these philosophical traditions had an obvious impact into his way of explaining psychological processes in connection with concupiscentia. Not only did Augustine implicitly receive and exploit these traditions, but he also explicitly moulded and criticized them in connection with concupiscentia. Eventually, Augustine conceives the philosophical traditions of emotions as partly useful but also partly inadequate to deal with concupiscentia (Ch 5). The role of concupiscentia in connection to divine grace and Christian renewal is analysed in the final chapter of the study. Augustine s gradual development in internalizing the effects of concupiscentia also into the life of a baptized Christian are elucidated, as are the strong limitations and mitigations Augustine makes to the concept when attaching it into the life under grace (sub gratia). A crucial part in the development of this function is played by Augustine s changing interpretation of Rom 7, and the way concupiscentia appears in Augustine s readings of this text is therefore also analysed. As a result of the analysis of these four distinct functions and contexts of concupiscentia, it is concluded that Augustine s concept of concupiscentia is fairly tightly and coherently connected to his views of central theological importance. Especially the functions of concupiscentia as a punishment and the function of concupiscentia in Christian renewal were both tightly interwoven into Augustine s view of God s being and God s grace. The study shows the importance of reading Augustine s discussions on evil desire with a constant awareness of their role in their larger context, that is, of their function in each situation. The study warns against too simplistic and unifying readings of Augustine s concupiscentia, emphasizing the need to acknowledge both the necessitating, sinful aspects of concupiscentia, and the domesticated features of concupiscentia during Christian renewal.

Carbon dynamics in peatlands under changing hydrology : Effects of water level drawdown on litter quality, microbial enzyme activities and litter decomposition rates

Pristine peatlands are carbon (C) accumulating wetland ecosystems sustained by a high water level (WL) and consequent anoxia that slows down decomposition. Persistent WL drawdown as a response to climate and/or land-use change directly affects decomposition: increased oxygenation stimulates decomposition of the old C (peat) sequestered under prior anoxic conditions. Responses of the new C (plant litter) in terms of quality, production and decomposability, and the consequences for the whole C cycle of peatlands are not fully understood. WL drawdown induces changes in plant community resulting in shift in dominance from Sphagnum and graminoids to shrubs and trees. There is increasing evidence that the indirect effects of WL drawdown via the changes in plant communities will have more impact on the ecosystem C cycling than any direct effects. The aim of this study is to disentangle the direct and indirect effects of WL drawdown on the new C by measuring the relative importance of 1) environmental parameters (WL depth, temperature, soil chemistry) and 2) plant community composition on litter production, microbial activity, litter decomposition rates and, consequently, on the C accumulation. This information is crucial for modelling C cycle under changing climate and/or land-use. The effects of WL drawdown were tested in a large-scale experiment with manipulated WL at two time scales and three nutrient regimes. Furthermore, the effect of climate on litter decomposability was tested along a north-south gradient. Additionally, a novel method for estimating litter chemical quality and decomposability was explored by combining Near infrared spectroscopy with multivariate modelling. WL drawdown had direct effects on litter quality, microbial community composition and activity and litter decomposition rates. However, the direct effects of WL drawdown were overruled by the indirect effects via changes in litter type composition and production. Short-term (years) responses to WL drawdown were small. In long-term (decades), dramatically increased litter inputs resulted in large accumulation of organic matter in spite of increased decomposition rates. Further, the quality of the accumulated matter greatly changed from that accumulated in pristine conditions. The response of a peatland ecosystem to persistent WL drawdown was more pronounced at sites with more nutrients. The study demonstrates that the shift in vegetation composition as a response to climate and/or land-use change is the main factor affecting peatland ecosystem C cycle and thus dynamic vegetation is a necessity in any models applied for estimating responses of C fluxes to changes in the environment. The time scale for vegetation changes caused by hydrological changes needs to extend to decades. This study provides grouping of litter types (plant species and part) into functional types based on their chemical quality and/or decomposability that the models could utilize. Further, the results clearly show a drop in soil temperature as a response to WL drawdown when an initially open peatland converts into a forest ecosystem, which has not yet been considered in the existing models.

How Can Sustainable Agricultural Systems Promote Food Security in a Changing Climate?

A theoretical framework of the link between climate change, rural development, sustainable agriculture, poverty, and food security is presented. Some options to respond to climate change are described. Current knowledge and potential effects on agricultural productivity is discussed. Necessary conditions for successful adaptation includes secured property rights to land, institutions that make market access possible and credit possibilities. The options of mitigation and enhanced adaptive capacity and the requirements for their implementation are discussed.

Finnish and Austrian Wood Markets in a Changing Environment

At present the operating environment of sawmills in Europe is changing and there are uncertainties related in raw material supply in many countries. The changes in the operating environment of roundwood markets and the effects followed by these changes have brought up several interesting issues from the viewpoint of research. Lately new factors have been influencing the roundwood markets, such as increasing interest towards wood-based energy and implementation of new energy policies as well as changes in wood trade flows that affect the domestic markets in many countries. This Master’s thesis studies the adaptation ability of Finnish roundwood markets in a changing operating environment, aiming to produce an up-to-date analysis considering new development trends. The study concentrates on the roundwood markets from the viewpoint of sawmill industry since the industry is dependent on the functioning of the markets and sawmills are highly affected by the changes on the roundwood markets. To facilitate international comparison, the study is implemented by comparing Finnish and Austrian roundwood markets and analysing changes happening in the two countries. Finland and Austria share rather similar characteristics in the roundwood market structures, forest resources and forest ownership as well as production of roundwood and sawnwood. In addition they both are big exporters of forest industry products. In this study changes in the operating environment of sawmill industry both in Finland as well as in Austria are compared to each other aiming to recognise the main similarities and differences between the countries. In addition both development possibilities as well as challenges followed by the changes are discussed. The aim of the study is to define the main challenges and possibilities confronted by the actors on the markets and also to find new perspectives to approach these. The study is implemented as a qualitative study. The theoretical framework of the study describes the operating environment of wood markets from the viewpoint of the sawmill industry and represents the effects of supply and demand on the wood markets. The primary research material of the study was gathered by interviewing high level experts of forestry and sawmill industry in both Finland and Austria. The aim was to receive as extensive country specific viewpoint from the markets as possible, hence interviewees represented different parties of the markets. After creating country-specific profiles based on the theoretical framework a cross-country comparison was implemented. As a consequence the main similarities and differences in the operating environment and on the roundwood markets of Finland and Austria were recognized. In addition the main challenges and possibilites were identified. The results of the study offer a wide analysis regarding the main similarities and differences of the wood markets of Finland and Austria and their operating environments as well as concerning challenges and possibilities faced on the markets.

Correlation of structural disorder with the reversible discharge capacity of nickel hydroxide electrode

Hydrothermal treatment of a slurry of badly crystalline (beta(bc)) nickel hydroxide at different temperatures (65-170 degrees C) results in the progressive ordering of the structure by the step-wise elimination of disorders. Interstratification is eliminated at 140 degrees C, while cation vacancies are eliminated at 170 degrees C. A small percentage of stacking faults continue to persist even in `crystalline' samples. Electrochemical investigations show that the crystalline nickel hydroxide has a very low (0.4 e/Ni) reversible charge storage capacity. An incidence of at least 15% stacking faults combined with cation vacancies is essential for nickel hydroxide to perform close to its theoretical (1 e/ Ni) discharge capacity. (c) 2005 The Electrochemical Society.

Canopy processes, fluxes and microclimate in a pine forest

Interaction between forests and the atmosphere occurs by radiative and turbulent transport. The fluxes of energy and mass between surface and the atmosphere directly influence the properties of the lower atmosphere and in longer time scales the global climate. Boreal forest ecosystems are central in the global climate system, and its responses to human activities, because they are significant sources and sinks of greenhouse gases and of aerosol particles. The aim of the present work was to improve our understanding on the existing interplay between biologically active canopy, microenvironment and turbulent flow and quantify. In specific, the aim was to quantify the contribution of different canopy layers to whole forest fluxes. For this purpose, long-term micrometeorological and ecological measurements made in a Scots pine (Pinus sylvestris) forest at SMEAR II research station in Southern Finland were used. The properties of turbulent flow are strongly modified by the interaction between the canopy elements: momentum is efficiently absorbed in the upper layers of the canopy, mean wind speed and turbulence intensities decrease rapidly towards the forest floor and power spectra is modulated by spectral short-cut . In the relative open forest, diabatic stability above the canopy explained much of the changes in velocity statistics within the canopy except in strongly stable stratification. Large eddies, ranging from tens to hundred meters in size, were responsible for the major fraction of turbulent transport between a forest and the atmosphere. Because of this, the eddy-covariance (EC) method proved to be successful for measuring energy and mass exchange inside a forest canopy with exception of strongly stable conditions. Vertical variations of within canopy microclimate, light attenuation in particular, affect strongly the assimilation and transpiration rates. According to model simulations, assimilation rate decreases with height more rapidly than stomatal conductance (gs) and transpiration and, consequently, the vertical source-sink distributions for carbon dioxide (CO2) and water vapor (H2O) diverge. Upscaling from a shoot scale to canopy scale was found to be sensitive to chosen stomatal control description. The upscaled canopy level CO2 fluxes can vary as much as 15 % and H2O fluxes 30 % even if the gs models are calibrated against same leaf-level dataset. A pine forest has distinct overstory and understory layers, which both contribute significantly to canopy scale fluxes. The forest floor vegetation and soil accounted between 18 and 25 % of evapotranspiration and between 10 and 20 % of sensible heat exchange. Forest floor was also an important deposition surface for aerosol particles; between 10 and 35 % of dry deposition of particles within size range 10 30 nm occurred there. Because of the northern latitudes, seasonal cycle of climatic factors strongly influence the surface fluxes. Besides the seasonal constraints, partitioning of available energy to sensible and latent heat depends, through stomatal control, on the physiological state of the vegetation. In spring, available energy is consumed mainly as sensible heat and latent heat flux peaked about two months later, in July August. On the other hand, annual evapotranspiration remains rather stable over range of environmental conditions and thus any increase of accumulated radiation affects primarily the sensible heat exchange. Finally, autumn temperature had strong effect on ecosystem respiration but its influence on photosynthetic CO2 uptake was restricted by low radiation levels. Therefore, the projected autumn warming in the coming decades will presumably reduce the positive effects of earlier spring recovery in terms of carbon uptake potential of boreal forests.

Search for Top-Quark Production via Flavor-Changing Neutral Currents in W+1 Jet Events at CDF

We report on the first search for top-quark production via flavor-changing neutral-current (FCNC) interactions in the non-standard-model process u(c)+g -> t using ppbar collision data collected by the CDF II detector. The data set corresponds to an integrated luminosity of 2.2/fb. The candidate events feature the signature of semileptonic top-quark decays and are classified as signal-like or background-like by an artificial neural network trained on simulated events. The observed discriminant distribution is in good agreement with the one predicted by the standard model and provides no evidence for FCNC top-quark production, resulting in a Bayesian upper limit on the production cross section sigma (u(c)+g -> t) u+g) c+g)

Updated search for the flavor-changing neutral-current decay D0→μ+μ- in pp̅ collisions at √s=1.96 TeV

We report on a search for the flavor-changing neutral-current decay D0 \to {\mu}+ {\mu}- in pp collisions at \surd s = 1.96 TeV using 360 pb-1 of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. A displaced vertex trigger selects long-lived D0 candidates in the {\mu}+ {\mu}-, {\pi}+{\pi}-, and K-{\pi}+ decay modes. We use the Cabibbo-favored D0 \to K-{\pi}+ channel to optimize the selection criteria in an unbiased manner, and the kinematically similar D0 \to{\pi}+ {\pi}- channel for normalization. We set an upper limit on the branching fraction (D0 --> {\mu}+ {\mu}-)