Counter-current Washing of Filter Cakes

The main objective of this thesis was to compare the efficiency of counter-current and co-current filter cake washing techniques. Filter cake washing is a common unit operation which is used in the chemical process industry for improving the recovery of the liquid phase or for purifying the solid phase of the filter cake. Counter-current displacement washing is more difficult to arrange and it requires additional process equipment but the advantage of counter-current method is that the consumption of wash water that is required for achieving certain filter cake purity may be considerably decreased when compared to the co-current washing method. This is true especially for materials that are difficult to wash. The literature part of this thesis consists of a review of filter cake washing in general, including the basic principles of co-current and counter-current techniques, and a description of the structure and operation of a horizontal vacuum belt filter, which is the equipment considered in the experimental part of this thesis. Also the most common cake washing models are introduced. The experiments were performed by washing wheat apatite filter cakes in a laboratory scale vacuum filter by using both co-current and counter-current washing methods. The main results of these tests were the washing curves that relate the purity of the filter cake to the amount of wash liquid used. Comparison between the obtained washing curves showed that both washing methods could be efficiently applied for achieving good washing results. The differences between the wash liquid consumptions in the co-current and counter-current washing methods were found to be surprisingly small but this is most probably explained by the relatively good washing characteristics of the apatite cakes. The washing models introduced in the literature part were compared with the results obtained from the experiments and it was found out that the studied cake washing processes could be described

Challenges and Means for the Front End Activities of Software Development

The front end of innovation is regarded as one of the most important steps in building new software products or services, and the most significant benefits in software development can be achieved through improvements in the front end activities. Problems in the front end phase have an impact on customer dissatisfaction with delivered software, and on the effectiveness of the entire software development process. When these processes are improved, the likelihood of delivering high quality software and business success increases. This thesis highlights the challenges and problems related to the early phases of software development, and provides new methods and tools for improving performance in the front end activities of software development. The theoretical framework of this study comprises two fields of research. The first section belongs to the field of innovation management, and especially to the management of the early phases of the innovation process, i.e. the front end of innovation. The second section of the framework is closely linked to the processes of software engineering, especially to the early phases of the software development process, i.e. the practice of requirements engineering. Thus, this study extends the theoretical knowledge and discloses the differences and similarities in these two fields of research. In addition, this study opens up a new strand for academic discussion by connecting these research directions. Several qualitative business research methodologies have been utilized in the individual publications to solve the research questions. The theoretical and managerial contribution of the study can be divided into three areas: 1) processes and concepts, 2) challenges and development needs, and 3) means and methods for the front end activities of software development. First, the study discloses the difference and similarities between the concepts of the front end of innovation and requirements engineering, and proposes a new framework for managing the front end of the software innovation process, bringing business and innovation perspectives into software development. Furthermore, the study discloses managerial perceptions of the similarities and differences in the concept of the front end of innovation between the software industry and the traditional industrial sector. Second, the study highlights the challenges and development needs in the front end phase of software development, especially challenges in communication, such as linguistic problems, ineffective communication channels, a communication gap between users/customers and software developers, and participation of multiple persons in software development. Third, the study proposes new group methods for improving the front end activities of software development, especially customer need assessment, and the elicitation of software requirements.

Ecological and Epidemiological Analyses of Multiple Sclerosis Relapse Rate

The underlying cause of many human autoimmune diseases is unknown, but several environmental factors are implicated in triggering the self-destructive immune reactions. Multiple Sclerosis (MS) is a chronic autoimmune disease of the central nervous system, potentially leading to persistent neurological deterioration. The cause of MS is not known, and apart from immunomodulatory treatments there is no cure. In the early phase of the disease, relapsing-remitting MS (RR-MS) is characterized by unpredictable exacerbations of the neurological symptoms called relapses, which can occur at different intervals ranging from 4 weeks to several years. Microbial infections are known to be able to trigger MS relapses, and the patients are instructed to avoid all factors that might increase the risk of infections and to properly use antibiotics as well as to take care of dental hygiene. Among those environmental factors which are known to increase susceptibility to infections, high ambient air inhalable particulate matter levels affect all people within a geographical region. During the period of interest in this thesis, the occurrence of MS relapses could be effectively reduced by injections of interferon, which has immunomodulatory and antiviral properties. In this thesis, ecological and epidemiological analyses were used to study the possible connection between MS relapse occurrence, population level viral infections and air quality factors, as well as the effects of interferon medication. Hospital archive data were collected retrospectively from 1986-2001, a period in time ranging from when interferon medication first became available until just before other disease-modifying MS therapies arrived on the market. The grouped data were studied with logistic regression and intervention analysis, and individual patient data with survival analysis. Interferons proved to be effective in the treatment of MS in this observational study, as the amount of MS exacerbations was lower during interferon use as compared to the time before interferon treatment. A statistically significant temporal relationship between MS relapses and inhalable particular matter (PM₁₀) concentrations was found in this study, which implies that MS patients are affected by the exposure to PM₁₀. Interferon probably protected against the effect of PM₁₀, because a significant increase in the risk of exacerbations was only observed in MS patients without interferon medication following environmental exposure to population level specific viral infections and PM₁₀. Apart from being antiviral, interferon could thus also attenuate the enhancement of immune reactions caused by ambient air PM₁₀. The retrospective approach utilizing carefully constructed hospital records proved to be an economical and reliable source of MS disease information for statistical analyses.

On the development of object functions and restrictions for shapes made with a turret punch press

This study presents the information required to describe the machine and device resources in the turret punch press environment which are needed for the development of the analysing method for automated production. The description of product and device resources and their interconnectedness is the starting point for method comparison the development of expenses, production planning and the performance of optimisation. The manufacturing method cannot be optimized unless the variables and their interdependence are known. Sheet metal parts in particular may then become remarkably complex, and their automatic manufacture may be difficult or, with some automatic equipment, even impossible if not know manufacturing properties. This thesis consists of three main elements, which constitute the triangulation. In the first phase of triangulation, the manufacture occuring on a turret punch press is examined in order to find the factors that affect the efficiency of production. In the second phase of triangulation, the manufacturability of products on turret punch presses is examined through a set of laboratory tests. The third phase oftriangulation involves an examination of five industry parts. The main key findings of this study are: all possible efficiency in high automation level machining cannot be achieved unless the raw materials used in production and the dependencies of the machine and tools are well known. Machine-specific manufacturability factors for turret punch presses were not taken into account in the industrial case samples. On the grounds of the performed tests and industrial case samples, the designer of a sheet metal product can directly influence the machining time, material loss, energy consumption and the number of tools required on a turret punch press by making decisions in the way presented in the hypothesis of thisstudy. The sheet metal parts to be produced can be optimised to bemanufactured on a turret punch press when the material to be used and the kinds of machine and tool options available are known. This provides in-depth knowledge of the machine and tool properties machine and tool-specifically. None of the optimisation starting points described here is a separate entity; instead, they are all connected to each other.

Mild Cognitive Impairment and Early Detection of Alzheimer`s Disease. A Positron Emission Tomography Study

Alzheimer`s disease (AD) is characterised neuropathologically by the presence of extracellular amyloid plaques, intraneuronal neurofibrillary tangles, and cerebral neuronal loss. The pathological changes in AD are believed to start even decades before clinical symptoms are detectable. AD gradually affects episodic memory, cognition, behaviour and the ability to perform everyday activities. Mild cognitive impairment (MCI) represents a transitional state between normal aging and dementia disorders, especially AD. The predictive accuracy of the current and commonly used MCI criteria devide this disorder into amnestic (aMCI) and non-amnestic (naMCI) MCI. It seems that many individuals with aMCI tend to convert to AD. However many MCI individuals will remain stable and some may even recover. At present, the principal drugs for the treatment of AD provide only symptomatic and palliative benefits. Safe and effective mechanism-based therapies are needed for this devastating neurodegenerative disease of later life. In conjunction with the development of new therapeutic drugs, tools for early detection of AD would be important. In future one of the challenges will be to detect at an early stage these MCI individuals who will convert to AD. Methods which can predict which MCI subjects will convert to AD will be much more important if the new drug candidates prove to have disease-arresting or even disease–slowing effects. These types of drugs are likely to have the best efficacy if administered in the early or even in the presymptomatic phase of the disease when the synaptic and neuronal loss has not become too widespread. There is no clinical method to determine with certainly which MCI individuals will progress to AD. However there are several methods which have been suggested as predictors of conversion to AD, e.g. increased [11C] PIB uptake, hippocampal atrophy in MRI, low CSF A beta 42 level, high CSF tau-protein level, apolipoprotein E (APOE) ε4 allele and impairment in episodic memory and executive functions. In the present study subjects with MCI appear to have significantly higher [¹¹C] PIB uptake vs healthy elderly in several brain areas including frontal cortex, the posterior cingulate, the parietal and lateral temporal cortices, putamen and caudate. Also results from this PET study indicate that over time, MCI subjects who display increased [¹¹C] PIB uptake appear to be significantly more likely to convert to AD than MCI subjects with negative [¹¹C] PIB retention. Also hippocampal atrophy seems to increase in MCI individuals clearly during the conversion to AD. In this study [¹¹C] PIB uptake increases early and changes relatively little during the AD process whereas there is progressive hippocampal atrophy during the disease. In addition to increased [¹¹C] PIB retention and hippocampal atrophy, the status of APOE ε4 allele might contribute to the conversion from MCI to AD.

Organizational mechanisms and conditions of individuals for knowledge sharing in post-acquisition integration

The challenges of knowledge sharing after cross-border acquisitions are widely recognised. The study took a new view to the subject by applying a two-level framework provided by the knowledge governance approach. The purpose of the study was to investigate the effects of organizational mechanisms on the conditions of individuals for knowledge sharing in post-acquisition integration context. Qualitative research methods were used in this case study. Individual interviews were performed within an international firm after a recent cross-border acquisition. The results showed that integrators, the rotation of the personnel from the acquiring firm and visits and meetings enhance the conditions at the individual level for knowledge sharing after the acquisition. Respectively, strategic change, matrix structure and foreign HRM practices challenge the conditions at the individual level for knowledge sharing in the early post-acquisition integration phase. The findings are supported by the prior research on knowledge management in acquisitions. In particular, the study enlightens how organizational level actions influence the conditions of individuals for knowledge sharing. The study suggests that organizations should adjust organizational mechanisms to support the conditions of individuals, in order to promote knowledge sharing in the early phase of the integration.

Induction practices : experiences of newly qualified teachers

The thesis consists of four studies (articles I–IV) and a comprehensive summary. The aim is to deepen understanding and knowledge of newly qualified teachers’ experiences of their induction practices. The research interest thus reflects the ambition to strengthen the research-based platform for support measures. The aim can be specified in the following four sub-areas: to scrutinise NQTs’ experiences of the profession in the transition from education to work (study I), to describe and analyse NQTs’ experiences of their first encounters with school and classroom (study II), to explore NQTs’ experiences of their relationships within the school community (study III), to view NQTs’ experiences of support through peer-group mentoring as part of the wider aim of collaboration and assessment (study IV). The overall theoretical perspective constitutes teachers’ professional development. Induction forms an essential part of this continuum and can primarily be seen as a socialisation process into the profession and the social working environment of schools, as a unique phase of teachers’ development contributing to certain experiences, and as a formal programme designed to support new teachers. These lines of research are initiated in the separate studies (I–IV) and deepened in the theoretical part of the comprehensive summary. In order to appropriately understand induction as a specific practice the lines of research are in the end united and discussed with help of practice theory. More precisely the theory of practice architectures, including semantic space, physical space-time and social space, are used. The methodological approach to integrating the four studies is above all represented by abduction and meta-synthesis. Data has been collected through a questionnaire survey, with mainly open-ended questions, and altogether ten focus group meetings with newly qualified primary school teachers in 2007–2008. The teachers (n=88 in questionnaire, n=17 in focus groups), had between one and three years of teaching experience. Qualitative content analysis and narrative analysis were used when analysing the data. What is then the collected picture of induction or the first years in the profession if scrutinising the results presented in the articles? Four dimensions seem especially to permeate the studies and emerge when they are put together. The first dimension, the relational ˗ emotional, captures the social nature of induction and teacher’s work and the emotional character intimately intertwined. The second dimension, the tensional ˗ mutable, illustrates the intense pace of induction, together with the diffuse and unclear character of a teacher’s job. The third dimension, the instructive ˗ developmental, depicts induction as a unique and intensive phase of learning, maturity and professional development. Finally, the fourth dimension, the reciprocal ˗ professional, stresses the importance of reciprocity and collaboration in induction, both formally and informally. The outlined four dimensions, or integration of results, describing induction from the experiences of new teachers, constitute part of a new synthesis, induction practice. This synthesis was generated from viewing the integrated results through the theoretical lens of practice architecture and the three spaces, semantic space, physical space-time and social space. In this way, a more comprehensive, refined and partially new architecture of teachers’ induction practices are presented and discussed.

Strategic external deployment of intellectual assets

Globalization, pervasiveness of technology and ICT, and the buildup of information societies and policies have lead to a growing abundance of knowledge and highly educated labour supply that is distributed widely. These changes have shifted the foundation of competitiveness to valuable knowledge resources which are now distributed widely across the globe, across actors in the value chain and across educated individuals in multiple organizations. Against this backdrop, the paradigm of open innovation (OI) has emerged as a new response to managing the increased amount of boundary-spanning knowledge flows in and out of the innovation process. The outbound mode of open innovation, that is to say the external exploitation of knowledge assets outside of the firm’s own products and services, has been the less-researched aspect of the concept and so far typically seen as concerning the outlicensing of unused technological assets to generate additional revenue. Given that open innovation is essentially a framework for the holistic structuring and management of crossboundary knowledge flows to improve a firm’s innovative performance, a close integration to corporate strategy seems imperative in order to fully benefit from it. Integrating open innovation to strategy leads to elevating its role from a fringe activity to a central innovation management issue that needs to be systematically managed. Building a structure that allows effective management necessitates linking open innovation activities to each phase of the innovation process. Previously, the connection between outbound OI and the earlier stages of innovation has not been studied. The thesis finds that connecting outbound OI to the entire innovation process of the firm, including the fuzzy front end of innovation, is critical for attaining strategic objectives and to the successful implementation and management of the activity. The practical purpose for the research is to enable companies to fully utilize their potential for outbound open innovation and to be able to implement and manage it from a strategic standpoint.

PET Imaging of Osteomyelitis. Feasibility of 18F-FDG, 68Ga-Chloride and 68Ga-DOTAVAP-P1 Tracers in Staphylococcal Bone Infections

Due to technical restrictions of the database system the title of the thesis does not show corretly on this page. Numbers in the title are in superscript. Please see the PDF-file for correct title. ---- Osteomyelitis is a progressive inflammatory disease of bone and bone marrow that results in bone destruction due to an infective microorganism, most frequently Staphylococcus aureus. Orthopaedic concern relates to the need for reconstructive and trauma-related surgical procedures in the fast grow¬ing population of fragile, aged patients, who have an increased susceptibility to surgical site infections. Depending on the type of osteomyelitis, infection may be acute or a slowly progressing, low-grade infection. Peri-implant infections lead to implant loosening. The emerging antibiotic resistance of com¬mon pathogens further complicates the situation. With current imaging methods, significant limitations exist in the diagnosing of osteomyelitis and implant-related infections. Positron emission tomography (PET) with a glucose analogue, 18F-fluoro¬deoxyglucose (18F-FDG), seems to facilitate a more accurate diagnosis of chronic osteomyelitis. The method is based on the increased glucose consumption of activated inflammatory cells. Unfortunately, 18F-FDG accumulates also in sterile inflammation regions and causes false-positive findings, for exam¬ple, due to post-operative healing processes. Therefore, there is a clinical need for new, more infection-specific tracers. In addition, it is still unknown why 18F-FDG PET imaging is less accurate in the detec¬tion of periprosthetic joint infections, most frequently due to Staphylococcus epidermidis. This doctoral thesis focused on testing novel PET tracers (68Ga-chloride and 68Ga-DOTAVAP-P1) for early detections of bone infections and evaluated the role of pathogen-related factors in the appli¬cations of 18F-FDG PET in the diagnostics of bone infections. For preclinical models of S. epidermidis and S. aureus bone/implant infections, the significance of the causative pathogen was studied with respect to 18F-FDG uptake. In a retrospective analysis of patients with confirmed bone infections, the significance of the presence or absence of positive bacterial cultures on 18F-FDG uptake was evalu¬ated. 18F-FDG and 68Ga-chloride resulted in a similar uptake in S. aureus osteomyelitic bones. However, 68Ga-chloride did not show uptake in healing bones, and therefore it may be a more-specific tracer in the early post-operative or post-traumatic phase. 68Ga-DOTAVAP-P1, a novel synthetic peptide bind¬ing to vascular adhesion protein 1 (VAP-1), was able to detect the phase of inflammation in healing bones, but the uptake of the tracer was elevated also in osteomyelitis. Low-grade peri-implant infec¬tions due to S. epidermidis were characterized by a low uptake of 18F-FDG, which reflects the virulence of the causative pathogen and the degree of leukocyte infiltration. In the clinical study, no relationship was found between the level of 18F-FDG uptake and the presence of positive or negative bacterial cul¬tures. Thus 18F-FDG PET may help to confirm metabolically active infection process in patients with culture-negative, histologically confirmed, low-grade osteomyelitis.

The Impact of National Innovation System on Entrepreneurial Venture Creation Process

The important role of entrepreneurship in countries’ economic development and overall society well-being is widely recognized by researchers, experts as well as policy makers. Every phase of the process of starting a new business is related to the interaction with at least one player of country innovation system and therefore the efficiency of this interaction may have an influence on the success of whole entrepreneurial process and consequently on the willingness of potential entrepreneurs to engage into this process. The study proposes a System Dynamics model for studying the impact of National Innovation System (NIS) on the entrepreneurial venture creation process. The developed model also takes country population aspect into account and provides results for estimation the effect various demographic tendencies on the process performance. The special impact is made on possible ways to facilitate the development of entrepreneurial framework conditions. Business incubators are seen as one of the effective tool for accomplishing such task. The study also provides the result for estimation of possible impact arising from properly functioned Business Incubators.

Before internationalisation : reflections of lateral rigidity on managerial decision making

The purpose of the study is to analyse lateral rigidity in the framework of pre-internationalisation to find out its reflections on managerial decision making. The interest of the study lies in the intersection of the meaningful but relatively stagnant concept of lateral rigidity, and the pre-internationalisation phase of companies that has received only a limited amount of research attention. The theoretical basis for the study is drawn from managerial decision making and internationalisation literatures. Firstly, the study aims to define the concept of lateral rigidity in order to secondly find out how it influences managers’ pre-internationalisation decision making. The study is theoretical in nature, and is based solely on literature examination. Concept analysis method is used to determine the attributes of lateral rigidity for the purpose of recognising the concept in the pre-internationalisation framework. The attributes that are found to comprise lateral rigidity are culture, know-how, uncertainty and attitude. Furthermore, these attributes are more specifically found to consist of environmental, personal and operational matters. Through the analysis of the pre-internationalisation literature it is discovered that all the attributes appear there, and present a variety of influences on pre-internationalisation decision making that can be characterised as being negative. The study finds that culture influences managers’ decision making via subjective reasoning and behaviour that stem from a domestic inclination, and via unfamiliarity with foreign markets. Against assumption, home cultural factors, e.g. values and customs, do not appear to have an influence. Know-how is found to influence decision making via managers’ previous experiences, subjective abiding perceptions, and the usage of previous operation patterns. Uncertainty, then again, influences managers’ risk perception, unfamiliarity avoidance, and the scope of potential international operations. Attitude is found to have a robust influence on managerial decision making via the usage of familiar processes and decision regimes, subjective preference of convention, and plausible results of operations. Ergo, the effects of lateral rigidity on managers show to represent an encumbrance in the pre-internationalisation phase; even though internationalisation would take place, the related decisions and actions are highly constrained. Especially the subjectivity of managers is seen to have a meaningful role in the decision making process.

ORCiD – Membership and implementation at Chalmers University of Technology

Poster at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014