Numerical approaches to new particle formation and growth in the atmosphere

Aerosols impact the planet and our daily lives through various effects, perhaps most notably those related to their climatic and health-related consequences. While there are several primary particle sources, secondary new particle formation from precursor vapors is also known to be a frequent, global phenomenon. Nevertheless, the formation mechanism of new particles, as well as the vapors participating in the process, remain a mystery. This thesis consists of studies on new particle formation specifically from the point of view of numerical modeling. A dependence of formation rate of 3 nm particles on the sulphuric acid concentration to the power of 1-2 has been observed. This suggests nucleation mechanism to be of first or second order with respect to the sulphuric acid concentration, in other words the mechanisms based on activation or kinetic collision of clusters. However, model studies have had difficulties in replicating the small exponents observed in nature. The work done in this thesis indicates that the exponents may be lowered by the participation of a co-condensing (and potentially nucleating) low-volatility organic vapor, or by increasing the assumed size of the critical clusters. On the other hand, the presented new and more accurate method for determining the exponent indicates high diurnal variability. Additionally, these studies included several semi-empirical nucleation rate parameterizations as well as a detailed investigation of the analysis used to determine the apparent particle formation rate. Due to their high proportion of the earth's surface area, oceans could potentially prove to be climatically significant sources of secondary particles. In the lack of marine observation data, new particle formation events in a coastal region were parameterized and studied. Since the formation mechanism is believed to be similar, the new parameterization was applied in a marine scenario. The work showed that marine CCN production is feasible in the presence of additional vapors contributing to particle growth. Finally, a new method to estimate concentrations of condensing organics was developed. The algorithm utilizes a Markov chain Monte Carlo method to determine the required combination of vapor concentrations by comparing a measured particle size distribution with one from an aerosol dynamics process model. The evaluation indicated excellent agreement against model data, and initial results with field data appear sound as well.

Theoretical and computational approaches on heterogeneous nucleation

Nucleation is the first step of a first order phase transition. A new phase is always sprung up in nucleation phenomena. The two main categories of nucleation are homogeneous nucleation, where the new phase is formed in a uniform substance, and heterogeneous nucleation, when nucleation occurs on a pre-existing surface. In this thesis the main attention is paid on heterogeneous nucleation. This thesis wields the nucleation phenomena from two theoretical perspectives: the classical nucleation theory and the statistical mechanical approach. The formulation of the classical nucleation theory relies on equilibrium thermodynamics and use of macroscopically determined quantities to describe the properties of small nuclei, sometimes consisting of just a few molecules. The statistical mechanical approach is based on interactions between single molecules, and does not bear the same assumptions as the classical theory. This work gathers up the present theoretical knowledge of heterogeneous nucleation and utilizes it in computational model studies. A new exact molecular approach on heterogeneous nucleation was introduced and tested by Monte Carlo simulations. The results obtained from the molecular simulations were interpreted by means of the concepts of the classical nucleation theory. Numerical calculations were carried out for a variety of substances nucleating on different substances. The classical theory of heterogeneous nucleation was employed in calculations of one-component nucleation of water on newsprint paper, Teflon and cellulose film, and binary nucleation of water-n-propanol and water-sulphuric acid mixtures on silver nanoparticles. The results were compared with experimental results. The molecular simulation studies involved homogeneous nucleation of argon and heterogeneous nucleation of argon on a planar platinum surface. It was found out that the use of a microscopical contact angle as a fitting parameter in calculations based on the classical theory of heterogeneous nucleation leads to a fair agreement between the theoretical predictions and experimental results. In the presented cases the microscopical angle was found to be always smaller than the contact angle obtained from macroscopical measurements. Furthermore, molecular Monte Carlo simulations revealed that the concept of the geometrical contact parameter in heterogeneous nucleation calculations can work surprisingly well even for very small clusters.

Emotional experience in psychotherapeutic interaction : Conversation analytical study on cognitive psychotherapy

The dissertation examines how emotional experiences are oriented to in the details of psychotherapeutic interaction. The data (57 audio recorded sessions) come from one therapist-patient dyad in cognitive psychotherapy. Conversation analysis is used as method. The dissertation consists of 4 original articles and a summary. The analyses explicate the therapist s practices of responding to the patient s affective expressions. Different types of affiliating responses are identified. It is shown that the affiliating responses are combined with, or build grounds for, more interpretive and challenging actions. The study also includes a case study of a session with strong misalignment between the therapist s and patient s orientations, showing how this misalignment is managed by the therapist. Moreover, through a longitudinal analysis of the transformation of a sequence type, the study suggests that therapeutic change processes can be located to sequential relations of actions. The practices found in this study are compared to earlier research on everyday talk and on medical encounters. It is suggested that in psychotherapeutic interaction, the generic norms of interaction considering affiliation and epistemic access, are modified for the purposes of therapeutic work. The study also shows that the practices of responding to emotional experience in psychotherapy can deviate from the everyday practices of affiliation. The results of the study are also discussed in terms of concepts arising from clinical theory. These include empathy, validation of emotion, therapeutic alliance, interpretation, challenging beliefs, and therapeutic change. The therapist s approach described in this study involves practical integration of different clinical theories. In general terms, the study suggests that in the details of interaction, psychotherapy recurrently performs a dual task of empathy and challenging in relation to the patient s ways of describing their experiences. Methodologically, the study discusses the problem of identifying actions in conversation analysis of psychotherapy and emotional interaction, and the possibility to apply conversation analysis in the study of therapeutic change.

Implications of Bohmian quantum ontology for psychopathology

This article discusses the prospects of quantum psychiatry from a Bohmian point of view, which provides an ontological interpretation of quantum theory, and extends such ontology to include mind. At first, we discuss the more general relevance of quantum theory to psychopathology. The basic idea is that because quantum theory emphasizes the role of wholeness, it might be relevant to psychopathology, where breakdown of unity in the mental domain is a key feature. We then discuss the role of information in psychopathology, and consider the connections with quantum theory in this area. In particular, we discuss David Bohm’s notion of active information, which arises in the ontological interpretation of quantum theory, and is suggested to play a fundamental role as the bridge between mind and matter. Some such bridge is needed if we are to understand how subtle mental properties are able to influence more manifest physical properties in the brain (all the way to the molecular and possibly microtubular level), and how changes in those possibly quantum‐level physical processes are able to influence higher cognitive functions. We also consider the implications of the notion of active information for psychopathology. The prospects of implementing the Bohmian scheme in neuroquantal terms are then briefly considered. Finally, we discuss some possible therapeutic implications of Bohm’s approach to information and the relation of mind and matter.

Implications of Bohmian quantum ontology for psychopathology

This article discusses the prospects of quantum psychiatry from a Bohmian point of view, which provides an ontological interpretation of quantum theory, and extends such ontology to include mind. At first, we discuss the more general relevance of quantum theory to psychopathology. The basic idea is that because quantum theory emphasizes the role of wholeness, it might be relevant to psychopathology, where breakdown of unity in the mental domain is a key feature. We then discuss the role of information in psychopathology, and consider the connections with quantum theory in this area. In particular, we discuss David Bohm’s notion of active information, which arises in the ontological interpretation of quantum theory, and is suggested to play a fundamental role as the bridge between mind and matter. Some such bridge is needed if we are to understand how subtle mental properties are able to influence more manifest physical properties in the brain (all the way to the molecular and possibly microtubular level), and how changes in those possibly quantum‐level physical processes are able to influence higher cognitive functions. We also consider the implications of the notion of active information for psychopathology. The prospects of implementing the Bohmian scheme in neuroquantal terms are then briefly considered. Finally, we discuss some possible therapeutic implications of Bohm’s approach to information and the relation of mind and matter.

The Problem of Implementation and its Relation to the Philosophy of Cognitive Science

According to certain arguments, computation is observer-relative either in the sense that many physical systems implement many computations (Hilary Putnam), or in the sense that almost all physical systems implement all computations (John Searle). If sound, these arguments have a potentially devastating consequence for the computational theory of mind: if arbitrary physical systems can be seen to implement arbitrary computations, the notion of computation seems to lose all explanatory power as far as brains and minds are concerned. David Chalmers and B. Jack Copeland have attempted to counter these relativist arguments by placing certain constraints on the definition of implementation. In this thesis, I examine their proposals and find both wanting in some respects. During the course of this examination, I give a formal definition of the class of combinatorial-state automata , upon which Chalmers s account of implementation is based. I show that this definition implies two theorems (one an observation due to Curtis Brown) concerning the computational power of combinatorial-state automata, theorems which speak against founding the theory of implementation upon this formalism. Toward the end of the thesis, I sketch a definition of the implementation of Turing machines in dynamical systems, and offer this as an alternative to Chalmers s and Copeland s accounts of implementation. I demonstrate that the definition does not imply Searle s claim for the universal implementation of computations. However, the definition may support claims that are weaker than Searle s, yet still troubling to the computationalist. There remains a kernel of relativity in implementation at any rate, since the interpretation of physical systems seems itself to be an observer-relative matter, to some degree at least. This observation helps clarify the role the notion of computation can play in cognitive science. Specifically, I will argue that the notion should be conceived as an instrumental rather than as a fundamental or foundational one.

Future chemistry teachers use of knowledge dimensions and high-order cognitive skills in pre-laboratory concept maps

This poster describes a pilot case study, which aim is to study how future chemistry teachers use knowledge dimensions and high-order cognitive skills (HOCS) in their pre-laboratory concept maps to support chemistry laboratory work. The research data consisted of 168 pre-laboratory concept maps that 29 students constructed as a part of their chemistry laboratory studies. Concept maps were analyzed by using a theory based content analysis through Anderson & Krathwohls' learning taxonomy (2001). This study implicates that novice concept mapper students use all knowledge dimensions and applying, analyzing and evaluating HOCS to support the pre-laboratory work.

Brain oscillatory responses, working memory and cognitive developmental stages in 11- and 14-year-old children: an ERD/ERS study

Aim: So far, most of the cognitive neuroscience studies investigating the development of brain activity in childhood have made comparisons between different age groups and ignored the individual stage of cognitive development. Given the wide variation in the rate of cognitive development, this study argues that chronological age alone cannot explain the developmental changes in brain activity. This study demonstrates how Piaget s theory and information on child s individual stage of development can complement the age-related evaluations of brain oscillatory activity. In addition, the relationship between cognitive development and working memory is investigated. Method: A total of 33 children (17 11-year-olds, 16 14-year-olds) participated in this study. The study consisted of behavioural tests and an EEG experiment. Behavioral tests included two Piagetian tasks (the Volume and Density task, the Pendulum task) and Raven s Standard Progressive Matrices task. During EEG experiment, subjects performed a modified version of the Sternberg s memory search paradigm which consisted of an auditorily presented memory set of 4 words and a probe word following these. The EEG data was analyzed using the event-related desynchronization / synchronization (ERD/ERS) method. The Pendulum task was used to assess the cognitive developmental stage of each subject and to form four groups based on age (11- or 14-year-olds) and cognitive developmental stage (concrete or formal operational stage). Group comparisons between these four groups were performed for the EEG data. Results and conclusions: Both age- and cognitive stage-related differences in brain oscillatory activity were found between the four groups. Importantly, age-related changes similar to those reported by previous studies were found also in this study, but these changes were modified by developmental stage. In addition, the results support a strong link between working memory and cognitive development by demonstrating differences in memory task related brain activity and cognitive developmental stages. Based on these findings it is suggested that in the future, comparisons of development of brain activity should not be based only on age but also on the individual cognitive developmental stage.

The international match: Metaphors as vehicles of social identity building in cross-border mergers

This article focuses on cultural identity-building in the cross-border merger context. To provide an alternative to the dominant essentialist analyses of cultures and cultural differences, cultural identitybuilding is conceptualized as a metaphoric process. The focus is on two processes inherent in the cross-border merger context: construction of images of Us and Them and construction of images of a Common Future. Based on an analysis of a special metaphor exercise carried out in a recent Finnish–Swedish merger, the article illustrates how the metaphoric perspective reveals specific cognitive, emotional and political aspects of cultural identity-building that easily remain ‘hidden’ in the case of more traditional approaches.

Cultural differences and postmerger problems: Misconceptions and cognitive simplifications.

Researchers and practitioners have increasingly explained post-merger organizational problems with cultural differences, especially in the context of cross-border mergers and acquisitions. It is suggested here that cultural differences have great explanatory power in the context of post-merger change processes. There are, however, problems with a number of superficial cultural conceptions that are common in research in this area and in managerial rhetoric. This critical article provocatively delineates misconceptions widely held by researchers and practitioners in this field, which not only disregard cultural differentiation, fragmentation, inconsistencies and ambiguities, but further, illustrate a lack of understanding of cultural permeability and embeddedness in the environment, an overemphasis on abstract values and lack of attention to organizational practices, an overemphasis on initial structural differences and lack of attention to the new cultural layer, a lack of recognition of the political dimensions and a failure to recognize cultural differences as sources of value and learning. In this article, the theoretical problems associated with these misconceptions are examined and new conceptual perspectives suggested. The risks at stake for decision makers are also discussed.

Cognitive Functioning in Alcohol and Other Substance Use Disorders in Young Adulthood : A Genetic Epidemiological Study

Alcohol and other substance use disorders (SUDs) result in great costs and suffering for individuals and families and constitute a notable public health burden. A multitude of factors, ranging from biological to societal, are associated with elevated risk of SUDs, but at the level of individuals, one of the best predictors is a family history of SUDs. Genetically informative twin and family studies have consistently indicated this familial risk to be mainly genetic. In addition, behavioral and temperamental factors such as early initiation of substance use and aggressiveness are associated with the development of SUDs. These familial, behavioral and temperamental risk factors often co-occur, but their relative importance is not well known. People with SUDs have also been found to differ from healthy controls in various domains of cognitive functioning, with poorer verbal ability being among the most consistent findings. However, representative population-based samples have rarely been used in neuropsychological studies of SUDs. In addition, both SUDs and cognitive abilities are influenced by genetic factors, but whether the co-variation of these traits might be partly explained by overlapping genetic influences has not been studied. Problematic substance use also often co-occurs with low educational level, but it is not known whether these outcomes share part of their underlying genetic influences. In addition, educational level may moderate the genetic etiology of alcohol problems, but gene-environment interactions between these phenomena have also not been widely studied. The incidence of SUDs peaks in young adulthood rendering epidemiological studies in this age group informative. This thesis investigated cognitive functioning and other correlates of SUDs in young adulthood in two representative population-based samples of young Finnish adults, one of which consisted of monozygotic and dizygotic twin pairs enabling genetically informative analyses. Using data from the population-based Mental Health in Early Adulthood in Finland (MEAF) study (n=605), the lifetime prevalence of DSM-IV any substance dependence or abuse among persons aged 21—35 years was found to be approximately 14%, with a majority of the diagnoses being alcohol use disorders. Several correlates representing the domains of behavioral and affective factors, parental factors, early initiation of substance use, and educational factors were individually associated with SUDs. The associations between behavioral and affective factors (attention or behavior problems at school, aggression, anxiousness) and SUDs were found to be largely independent of factors from other domains, whereas daily smoking and low education were still associated with SUDs after adjustment for behavioral and affective factors. Using a wide array of neuropsychological tests in the MEAF sample and in a subsample (n=602) of the population-based FinnTwin16 (FT16) study, consistent evidence of poorer verbal cognitive ability related to SUDs was found. In addition, participants with SUDs performed worse than those without disorders in a task assessing psychomotor processing speed in the MEAF sample, whereas no evidence of more specific cognitive deficits was found in either sample. Biometrical structural equation models of the twin data suggested that both alcohol problems and verbal ability had moderate heritabilities (0.54—0.72), and that their covariation could be explained by correlated genetic influences (genetic correlations -0.20 to -0.31). The relationship between educational level and alcohol problems, studied in the full epidemiological FT16 sample (n=4,858), was found to reflect both genetic correlation and gene-environment interaction. The co-occurrence of low education and alcohol problems was influenced by overlapping genetic factors. In addition, higher educational level was associated with increased relative importance of genetic influences on alcohol problems, whereas environmental influences played a more important role in young adults with lower education. In conclusion, SUDs, especially alcohol abuse and dependence, are common among young Finnish adults. Behavioral and affective factors are robustly related to SUDs independently of many other factors, and compared to healthy peers, young adults who have had SUDs during their life exhibit significantly poorer verbal cognitive ability, and possibly less efficient psychomotor processing. Genetic differences between individuals explain a notable proportion of individual differences in risk of alcohol dependence, verbal ability, and educational level, and the co-occurrence of alcohol problems with poorer verbal cognition and low education is influenced by shared genetic backgrounds. Finally, various environmental factors related to educational level in young adulthood moderate the relative importance of genetic factors influencing the risk of alcohol problems, possibly reflecting differences in social control mechanisms related to educational level.

Cognitive functioning and its heritability in bipolar I disorder

Bipolar I disorder is a severe psychiatric disorder characterized by episodic mood alterations that can be manic, depressive or mixed. Bipolar disorder seems to be highly genetic, but the etiology of this complex disorder has remained elusive. In recent years, studies have found that euthymic patients with bipolar disorder may have impairments particularly in executive functioning, verbal learning and memory. These impairments may be present also among some of the relatives of these patients, who may be vulnerable to the disorder. Using neuropsychological variables as endophenotypes, i.e. intermediate phenotypes between genes and the phenotypes, has been suggested to aid search for the etiological background of the disorder, but evidence is sparse on whether these variables fulfill the criteria for endophenotypes. The present thesis is part of the Genetic Epidemiology and Molecular Genetics of Severe Mental Disorders in Finland project. The specific aim was to investigate whether neuropsychological test variables would indicate genetic liability to the disorder and could therefore be regarded as endophenotypes. Thus, cognitive functions and their heritability were studied in bipolar I disorder patients and in their unaffected first-degree relatives from a population-based sample of families, comparing them to a population-based control group. In order to add homogeneity to the subgroups of bipolar disorder patients and their relatives, cognitive functions and their heritability were further studied in a group of families affected by bipolar I disorder only (bipolar families) and another group of families affected by both bipolar I disorder and schizophrenia or schizoaffective disorders (mixed families). Finally, the effect of processing speed on other cognitive functions was investigated. The study showed that especially executive functioning and processing speed fulfilled the endophenotype criteria. Impairments in these functions were found in bipolar patients and in their relatives irrespective of other severe psychopathology in the family. These functions were highly heritable in these families. Study also showed that generalized impairment in verbal memory may associate more with bipolar disorder than to vulnerability to other psychotic disorders, and be more related to fully developed disease; impairments in verbal learning and memory were found only in patients, and they were not found to be highly heritable. Finally, the most potential endophenotype, i.e. processing speed, seemed to contribute to a range of other cognitive dysfunctions seen in bipolar disorder patients. Processing speed, in particular, has also been shown to be a valid endophenotype in subsequent association analyses in psychiatric genetics in Finland and internationally. Information concerning cognitive impairments and their association with the psychosocial consequences of bipolar disorder is important in planning treatment. It is also important to understand and acknowledge that patients may have cognitive impairments that affect their everyday life. Psychosocial interventions and neuropsychological rehabilitation may supplement other conventional treatments for bipolar patients.