992 resultados para 10-PHENANTHROLINE-5
Resumo:
What is a miracle and what can we know about miracles? A discussion of miracles in anglophone philosophy of religion literature since the late 1960s. The aim of this study is to systematically describe and philosophically examine the anglophone discussion on the subject of miracles since the latter half of the 1960s. The study focuses on two salient questions: firstly, what I will term the conceptual-ontological question of the extent to which we can understand miracles and, secondly, the epistemological question of what we can know about miracles. My main purpose in this study is to examine the various viewpoints that have been submitted in relation to these questions, how they have been argued and on what presuppositions these arguments have been based. In conducting the study, the most salient dimension of the various discussions was found to relate to epistemological questions. In this regard, there was a notable confrontation between those scholars who accept miracles and those who are sceptical of them. On the conceptual-ontological side I recognised several different ways of expressing the concept of miracle . I systematised the discussion by demonstrating the philosophical boundaries between these various opinions. The first and main boundary was related to ontological knowledge. On one side of this boundary I placed the views which were based on realism and objectivism. The proponents of this view assumed that miraculousness is a real property of a miraculous event regardless of how we can perceive it. On the other side I put the views which tried to define miraculousness in terms of subjectivity, contextuality and epistemicity. Another essential boundary which shed light on the conceptual-ontological discussion was drawn in relation to two main views of nature. The realistic-particularistic view regards nature as a certain part of reality. The adherents of this presupposition postulate a supernatural sphere alongside nature. Alternatively, the nominalist-universalist view understands nature without this kind of division. Nature is understood as the entire and infinite universe; the whole of reality. Other, less important boundaries which shed light on the conceptual-ontological discussion were noted in relation to views regarding the laws of nature, for example. I recognised that the most important differences between the epistemological approaches were in the different views of justification, rationality, truth and science. The epistemological discussion was divided into two sides, distinguished by their differing assumptions in relation to the need for evidence. Adherents of the first (and noticeably smaller) group did not see any epistemological need to reach a universal and common opinion about miracles. I discovered that these kinds of views, which I called non-objectivist, had subjectivist and so-called collectivist views of justification and a contextualist view of rationality. The second (and larger) group was mainly interested in discerning the grounds upon which to establish an objective and conclusive common view in relation to the epistemology of miracles. I called this kind of discussion an objectivist discussion and this kind of approach an evidentialist approach. Most of the evidentialists tried to defend miracles and the others attempted to offer evidence against miracles. Amongst both sides, there were many different variations according to emphasis and assumption over how they saw the possibilities to prove their own view. The common characteristic in all forms of evidentialism was a commitment to an objectivist notion of rationality and a universalistic notion of justification. Most evidentialists put their confidence in science in one way or another. Only a couple of philosophers represented the most moderate version of evidentialism; they tried to remove themselves from the apparent controversy and contextualised the different opinions in order to make some critical comments on them. I called this kind of approach a contextualising form of evidentialism. In the final part of the epistemological chapter, I examined the discussion about the evidential value of miracles, but nothing substantially new was discovered concerning the epistemological views of the authors.
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A computer program has been developed for the prediction of buoyancy-driven laminar and turbulent flow in rectangular air-filled two-dimensional cavities with differentially heated side walls. Laminar flow predictions for a square cavity and Rayleigh numbers from Ra = 10^3 up to the onset of unsteady flow have been obtained. Accurate solutions for Ra = 5 x 10^6, 10^7, 5 x 10^7 and 10^8 are presented and an estimate for the critical Rayleigh number at which the steady laminar flow becomes unsteady is given for this geometry. Numerical predictions of turbulent flow have been obtained for RaH~0(10^9 -10^11 ) and compared with existing experimental data. A previously developed second moment closure model (Behnia et al. 1987) has been used to model the turbulence. Results indicate that a second moment closure model is capable of predicting the observed flow features.
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In the course of my research for my thesis The Q Gospel and Psychohistory, I moved on from the accounts of the Cynics ideals to psychohistorical explanations. Studying the texts dealing with the Cynics and the Q Gospel, I was amazed by the fact that these texts actually portrayed people living in greater poverty than they had to. I paid particular attention to the fact that the Q Gospel was born in traumatising, warlike circumstances. Psychiatric traumatology helped me understand the Q Gospel and other ancient documents using historical approaches in a way that would comply with modern behavioural science. Even though I found some answers to the questions I had posed in my research, the main result of my research work is the justification of the question: Is it important to ask whether there is a connection between the ethos expressed by means of the religious language of the Q Gospel and the predominantly war-related life experiences typical to Palestine at the time. As has been convincingly revealed by a number of studies, traumatic events contribute to the development of psychotic experiences. I approached the problematic nature, significance and complexity of the ideal of poverty and this warlike environment by clarifying the history of psychohistorical literary research and the interpretative contexts associated with Sigmund Freud, Jacques Lacan and Melanie Klein. It is justifiable to question abnormal mentality, but there is no reliable return from the abnormal mentality described in any particular text to the only affecting factor. The popular research tendency based on the Oedipus complex is just as controversial as the Oedipus complex itself. The sociological frameworks concerning moral panics and political paranoia of an outer and inner danger fit quite well with the construction of the Q Gospel. Jerrold M. Post, M.D., Professor of Psychiatry, Political Psychology and Interna-tional Affairs at George Washington University, and founder and director of the Center for the Analysis of Personality and Political Behavior for the Central Intelligence Agency, has focused on the role played by charisma in the attracting of followers and detailed the psychological styles of a "charismatic" leader. He wrote the books Political Paranoia and Leaders and Their Followers in a Dangerous World: the Psychology of Political Behavior among others. His psychoanalytic vocabulary was useful for my understanding of the minds and motivations involved in the Q Gospel s formation. The Q sect began to live in a predestined future, with the reality and safety of this world having collapsed in both their experience and their fantasies. The deep and clear-cut divisions into good and evil that are expressed in the Q Gospel reveal the powerful nature of destructive impulses, envy and overwhelming anxiety. Responsible people who influenced the Q Gospel's origination tried to mount an ascetic defense against anxiety, denying their own needs, focusing their efforts on another objective (God s Kingdom) and a regressive, submissive earlier phase of development (a child s carelessness). This spiritual process was primarily an ecclesiastic or group-dynamical tactic to give support to the power of group leaders.
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PROFESSION, PERSON AND WORLDVIEW AT A TURNING POINT A Study of University Libraries and Library Staff in the Information Age 1970 - 2005 The incongruity between commonly held ideas of libraries and librarians and the changes that have occurred in libraries since 2000 provided the impulse for this work. The object is to find out if the changes of the last few decades have penetrated to a deeper level, that is, if they have caused changes in the values and world views of library staff and management. The study focuses on Finnish university libraries and the people who work in them. The theoretical framework is provided by the concepts of world view (values, the concept of time, man and self, the experience of the supernatural and the holy, community and leadership). The viewpoint, framework and methods of the study place it in the area of Comparative Religion by applying the world view framework. The time frame is the information age, which has deeply affected Finnish society and scholarly communication from 1970 to 2005. The source material of the study comprises 30 life stories; somewhat more than half of the stories come from the University of Helsinki, and the rest from the other eight universities. Written sources include library journals, planning documents and historical accounts of libraries. The experiences and research diaries of the research worker are also used as source material. The world view questions are discussed on different levels: 1) recognition of the differences and similarities in the values of the library sphere and the university sphere, 2) examination of the world view elements, community and leadership based on the life stories, and 3) the three phases of the effects of information technology on the university libraries and those who work in them. In comparing the values of the library sphere and the university sphere, the appreciation of creative work and culture as well as the founding principles of science and research are jointly held values. The main difference between the values in the university and library spheres concerns competition and service. Competition is part of the university as an institution of research work. The core value of the library sphere is service, which creates the essential ethos of library work. The ethical principles of the library sphere also include the values of democracy and equality as well as the value of intellectual freedom. There is also a difference between an essential value in the university sphere, the value of autonomy and academic freedom on the one hand, and the global value of the library sphere - organizing operations in a practical and efficient way on the other hand. Implementing this value can also create tension between the research community and the library. Based on the life stories, similarities can be found in the values of the library staff members. The value of service seems to be of primary importance for all who are committed to library work and who find it interesting and rewarding. The service role of the library staff can be extended from information services provider to include the roles of teacher, listener and even therapist, all needed in a competitive research community. The values of democracy and equality also emerge fairly strongly. The information age development has progressed in three phases in the libraries from the 1960s onward. In the third phase beginning in the mid 1990s, the increased usage of electronic resources has set fundamental changes in motion. The changes have affected basic values and the concept of time as well as the hierarchies and valuations within the library community. In addition to and as a replacement for the library possessing a local identity and operational model, a networked, global library is emerging. The changes have brought tension both to the library communities and to the relationship between the university community and the library. Future orientation can be said to be the key concept for change; it affects where the ideals and models for operations are taken from. Future orientation manifests itself as changes in metaphors, changes in the model of a good librarian and as communal valuations. Tension between the libraries and research communities can arise if the research community pictures the library primarily as a traditional library building with a local identity, whereas the 21st century library staff and directors are affected by future orientation and membership in a networked library sphere, working proactively to develop their libraries.
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Although shame is a universal human emotion and is one of the most difficult emotions to overcome, its origins and nature as well as its effects on psychosocial functioning are not well understood or defined. While psychological and spiritual counselors are aware of the effects and consequences of shame for an individual s internal well-being and social life, shame is often still considered a taboo topic and is not given adequate attention. This study aims to explain the developmental process and effects of shame and shame-proneness for individuals and provide tools for practitioners to work more effectively with their clients who struggle with shame. This study presents the empirical foundation for a grounded theory that describes and explains the nature, origins, and consequences of shame-proneness. The study focused on Finnish participants childhood, adolescence and adulthood experiences and why they developed shame-proneness, what it meant for them as children and adolescents and what it meant for them as adults. The data collection phase of this study began in 2000. The participants were recruited through advertisements in local and country-wide newspapers and magazines. Altogether 325 people responded to the advertisements by sending an essay concerning their shame and guilt experiences. For the present study, 135 essays were selected and from those who sent an essay 19 were selected for in-depth interviews. In addition to essays and interviews, participants personal notebooks and childhood hospital and medical reports as well as their scores on the Internalized Shame Scale were analyzed. The development of shame-proneness and significant experiences and events during childhood and adolescence (e.g., health, parenting and parents behavior, humiliation, bullying, neglect, maltreatment and abuse) are discussed and the connections of shame-proneness to psychological concepts such as self-esteem, attachment, perfectionism, narcissism, submissiveness, pleasing others, heightened interpersonal subjectivity, and codependence are explained. Relationships and effects of shame-proneness on guilt, spirituality, temperament, coping strategies, defenses, personality formation and psychological health are also explicated. In addition, shame expressions and the development of shame triggers as well as internalized and externalized shame are clarified. These connections and developments are represented by the core category lack of gaining love, validation and protection as the authentic self. The conclusions drawn from the study include a categorization of shame-prone Finnish people according to their childhood and adolescent experiences and the characteristics of their shame-proneness and personality. Implications for psychological and spiritual counseling are also discussed. Key words: shame, internalized shame, external shame, shame development, shame triggers, guilt, self-esteem, attachment, narcissism, perfectionism, submissiveness, codependence, childhood neglect, childhood abuse, childhood maltreatment, emotional abuse, sexual abuse, spiritual abuse, psychological well-being
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How did Søren Kierkegaard (1813 1855) situate the human subject into historical and social actuality? How did he take into consideration his own situatedness? As key for understanding these questions the research takes the ideal of living poetically that Kierkegaard outlined in his dissertation. In The Concept of Irony (1841) Kierkegaard took up this ideal of the Romantic ironists and made it into an ethical-religious ideal. For him the ideal of living poetically came to mean 1) becoming brought up by God, while 2) assuming ethical-religiously one s role and place in the historical actuality. Through an exegesis of Kierkegaard s texts from 1843 to 1851 it is shown how this ideal governed Kierkegaard s thought and action throughout his work. The analysis of Kierkegaard s ideal of living poetically not only a) shows how the Kierkegaardian subject is situated in its historical context. It also b) sheds light on Kierkegaard s social and political thought, c) helps to understand Kierkegaard s character as a religious thinker, and d) pits his ethical-religious orientation in life against its scientific and commonsense alternatives. The research evaluates the rationality of the way of life championed by Kierkegaard by comparing it with ways of life dominated by reflection and reasoning. It uses Kierkegaard s ideal of living poetically in trying to understand the tensions between religious and unreligious ways of life.
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Amidopyrine (1-phenyl-2,3-dimethyl-4-dimethylaminopyrazolone), C13HzvN30, a dimethylamino derivative of antipyrine and an important analgesic and antipyretic agent, crystallizes in the triclinic space group P1 with four molecules in a unit cell of dimensions a= 7.458 (5), b = 10.744 (5), c= 17.486 (15)/~,, e=98.6 (2),/~= 85.6 (3), y= 108-6 (2) . The structure was solved by direct methods and refined to an R value of 0.055 for 3706 photographically observed reflexions. The dimensions of the two crystallographically independent molecules are very nearly the same. The pyrazolone moiety in the molecule has dimensions comparable to those in antipyrine. Unlike antipyrine, the molecular dimensions of amidopyrine in the free state (the present structure) are close to those found in some of its hydrogenbonded complexes. Thus it appears that the presence of the dimethylamino group makes the molecule more resistant to changes in its dimensions resulting from molecular association. An attempt has also been made to correlate the polar nature of the pyrazolone moiety and the hybridization state of the hetero nitrogen atoms in antipyrine, amidopyrine and their complexes.
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Väitöskirjassani tarkastelen informaatiohyödykkeiden ja tekijänoikeuksien taloustiedettä kahdesta eri perspektiivistä. Niistä ensimmäinen kuuluu endogeenisen kasvuteorian alaan. Väitöskirjassani yleistän ”pool of knowledge” -tyyppisen endogeenisen kasvumallin tilanteeseen, jossa patentoitavissa olevalla innovaatiolla on minimikoko, ja jossa uudenlaisen tuotteen patentoinut yritys voi menettää monopolinsa tuotteeseen jäljittelyn johdosta. Mallin kontekstissa voidaan analysoida jäljittelyn ja innovaatioilta vaaditun ”minimikoon” vaikutuksia hyvinvointiin ja talouskasvuun. Kasvun maksimoiva imitaation määrä on mallissa aina nolla, mutta hyvinvoinnin maksimoiva imitaation määrä voi olla positiivinen. Talouskasvun ja hyvinvoinnin maksimoivalla patentoitavissa olevan innovaation ”minimikoolla” voi olla mikä tahansa teoreettista maksimia pienempi arvo. Väitöskirjani kahdessa jälkimmäisessä pääluvussa tarkastelen informaatiohyödykkeiden kaupallista piratismia mikrotaloustieteellisen mallin avulla. Informaatiohyödykkeistä laittomasti tehtyjen kopioiden tuotantokustannukset ovat pienet, ja miltei olemattomat silloin kun niitä levitetään esimerkiksi Internetissä. Koska piraattikopioilla on monta eri tuottajaa, niiden hinnan voitaisiin mikrotaloustieteen teorian perusteella olettaa laskevan melkein nollaan, ja jos näin kävisi, kaupallinen piratismi olisi mahdotonta. Mallissani selitän kaupallisen piratismin olemassaolon olettamalla, että piratismista saatavan rangaistuksen uhka riippuu siitä, kuinka monille kuluttajille piraatti tarjoaa laittomia hyödykkeitä, ja että se siksi vaikuttaa piraattikopioiden markkinoihin mainonnan kustannuksen tavoin. Kaupallisten piraattien kiinteiden kustannusten lisääminen on mallissani aina tekijänoikeuksien haltijan etujen mukaista, mutta ”mainonnan kustannuksen” lisääminen ei välttämättä ole, vaan se saattaa myös alentaa laillisten kopioiden myynnistä saatavia voittoja. Tämä tulos poikkeaa vastaavista aiemmista tuloksista sikäli, että se pätee vaikka tarkasteltuihin informaatiohyödykkeisiin ei liittyisi verkkovaikutuksia. Aiemmin ei-kaupallisen piratismin malleista on usein johdettu tulos, jonka mukaan informaatiohyödykkeen laittomat kopiot voivat kasvattaa laillisten kopioiden myynnistä saatavia voittoja jos laillisten kopioiden arvo niiden käyttäjille riippuu siitä, kuinka monet muut kuluttajat käyttävät samanlaista hyödykettä ja jos piraattikopioiden saatavuus lisää riittävästi laillisten kopioiden arvoa. Väitöskirjan viimeisessä pääluvussa yleistän mallini verkkotoimialoille, ja tutkin yleistämäni mallin avulla sitä, missä tapauksissa vastaava tulos pätee myös kaupalliseen piratismiin.
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The dissertation consists of four essays and a comprehensive introduction that discusses the topics, methods, and most prominent theories of philosophical moral psychology. I distinguish three main questions: What are the essential features of moral thinking? What are the psychological conditions of moral responsibility? And finally, what are the consequences of empirical facts about human nature to normative ethics? Each of the three last articles focuses on one of these issues. The first essay and part of the introduction are dedicated to methodological questions, in particular the relationship between empirical (social) psychology and philosophy. I reject recent attempts to understand the nature of morality on the basis of empirical research. One characteristic feature of moral thinking is its practical clout: if we regard an action as morally wrong, we either refrain from doing it even against our desires and interests, or else feel shame or guilt. Moral views seem to have a conceptual connection to motivation and emotions – roughly speaking, we can’t conceive of someone genuinely disapproving an action, but nonetheless doing it without any inner motivational conflict or regret. This conceptual thesis in moral psychology is called (judgment) internalism. It implies, among other things, that psychopaths cannot make moral judgments to the extent that they are incapable of corresponding motivation and emotion, even if they might say largely the words we would expect. Is internalism true? Recently, there has been an explosion of interest in so-called experimental philosophy, which is a methodological view according to which claims about conceptual truths that appeal to our intuitions should be tested by way of surveys presented to ordinary language users. One experimental result is that the majority of people are willing to grant that psychopaths make moral judgments, which challenges internalism. In the first article, ‘The Rise and Fall of Experimental Philosophy’, I argue that these results pose no real threat to internalism, since experimental philosophy is based on a too simple conception of the relationship between language use and concepts. Only the reactions of competent users in pragmatically neutral and otherwise conducive circumstances yield evidence about conceptual truths, and such robust intuitions remain inaccessible to surveys for reasons of principle. The epistemology of folk concepts must still be based on Socratic dialogue and critical reflection, whose character and authority I discuss at the end of the paper. The internal connection between moral judgment and motivation led many metaethicists in the past century to believe along Humean lines that judgment itself consists in a pro-attitude rather than a belief. This expressivist view, as it is called these days, has far-reaching consequences in metaethics. In the second essay I argue that perhaps the most sophisticated form of contemporary expressivism, Allan Gibbard’s norm-expressivism, according to which moral judgments are decisions or contingency plans, is implausible from the perspective of the theory of action. In certain circumstances it is possible to think that something is morally required of one without deciding to do so. Morality is not a matter of the will. Instead, I sketch on the basis of Robert Brandom’s inferentialist semantics a weak form of judgment internalism, according to which the content of moral judgment is determined by a commitment to a particular kind of practical reasoning. The last two essays in the dissertation emphasize the role of mutual recognition in the development and maintenance of responsible and autonomous moral agency. I defend a compatibilist view of autonomy, according to which agents who are unable to recognize right and wrong or act accordingly are not responsible for their actions – it is not fair to praise or blame them, since they lacked the relevant capacity to do otherwise. Conversely, autonomy demands an ability to recognize reasons and act on them. But as a long tradition in German moral philosophy whose best-known contemporary representative is Axel Honneth has it, both being aware of reasons and acting on them requires also the right sort of higher-order attitudes toward the self. Without self-respect and self-confidence we remain at the mercy of external pressures, even if we have the necessary normative competence. These attitudes toward the self, in turn, are formed through mutual recognition – we value ourselves when those who we value value us. Thus, standing in the right sort of relations of recognition is indirectly necessary for autonomy and moral responsibility. Recognition and valuing are concretely manifest in actions and institutions, whose practices make possible participation on an equal footing. Seeing this opens the way for a kind of normative social criticism that is grounded in the value of freedom and automomy, but is not limited to defending negative rights. It thus offers a new way to bridge the gap between liberalism and communitarianism.
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This work is concerned with presenting a modified theoretical approach to the study of centre-periphery relations in the Russian Federation. In the widely accepted scientific discourse, the Russian federal system under the Yeltsin Administration (1991-2000) was asymmetrical; largely owing to the varying amount of structural autonomy distributed among the federation s 89 constituent units. While providing an improved understanding as to which political and socio-economic structures contributed to federal asymmetry, it is felt that associated large N-studies have underemphasised the role played by actor agency in re-shaping Russian federal institutions. It is the main task of this thesis to reintroduce /re-emphasise the importance of actor agency as a major contributing element of institutional change in the Russian federal system. By focusing on the strategic agency of regional elites simultaneously within regional and federal contexts, the thesis adopts the position that political, ethnic and socio-economic structural factors alone cannot fully determine the extent to which regional leaders were successful in their pursuit of economic and political pay-offs from the institutionally weakened federal centre. Furthermore, this work hypothesises that under conditions of federal institutional uncertainty, it is the ability of regional leaders to simultaneously interpret various mutable structural conditions then translate them into plausible strategies which accounts for the regions ability to extract variable amounts of economic and political pay-offs from the Russian federal system. The thesis finds that while the hypothesis is accurate in its theoretical assumptions, several key conclusions provide paths for further inquiry posed by the initial research question. First, without reliable information or stable institutions to guide their actions, both regional and federal elites were forced into ad-hoc decision-making in order to maintain their core strategic focus: political survival. Second, instead of attributing asymmetry to either actor agency or structural factors exclusively, the empirical data shows that both agency and structures interact symbiotically in the strategic formulation process, thus accounting for the sub-optimal nature of several of the actions taken in the adopted cases. Third, as actor agency and structural factors mutate over time, so, too do the perceived payoffs from elite competition. In the case of the Russian federal system, the stronger the federal centre became, the less likely it was that regional leaders could extract the high degree of economic and political pay-offs that they clamoured for earlier in the Yeltsin period. Finally, traditional approaches to the study of federal systems which focus on institutions as measures of federalism are not fully applicable in the Russian case precisely because the institutions themselves were a secondary point of contention between competing elites. Institutional equilibriums between the regions and Moscow were struck only when highly personalised elite preferences were satisfied. Therefore the Russian federal system is the product of short-term, institutional solutions suited to elite survival strategies developed under conditions of economic, political and social uncertainty.
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Many species inhabit fragmented landscapes, resulting either from anthropogenic or from natural processes. The ecological and evolutionary dynamics of spatially structured populations are affected by a complex interplay between endogenous and exogenous factors. The metapopulation approach, simplifying the landscape to a discrete set of patches of breeding habitat surrounded by unsuitable matrix, has become a widely applied paradigm for the study of species inhabiting highly fragmented landscapes. In this thesis, I focus on the construction of biologically realistic models and their parameterization with empirical data, with the general objective of understanding how the interactions between individuals and their spatially structured environment affect ecological and evolutionary processes in fragmented landscapes. I study two hierarchically structured model systems, which are the Glanville fritillary butterfly in the Åland Islands, and a system of two interacting aphid species in the Tvärminne archipelago, both being located in South-Western Finland. The interesting and challenging feature of both study systems is that the population dynamics occur over multiple spatial scales that are linked by various processes. My main emphasis is in the development of mathematical and statistical methodologies. For the Glanville fritillary case study, I first build a Bayesian framework for the estimation of death rates and capture probabilities from mark-recapture data, with the novelty of accounting for variation among individuals in capture probabilities and survival. I then characterize the dispersal phase of the butterflies by deriving a mathematical approximation of a diffusion-based movement model applied to a network of patches. I use the movement model as a building block to construct an individual-based evolutionary model for the Glanville fritillary butterfly metapopulation. I parameterize the evolutionary model using a pattern-oriented approach, and use it to study how the landscape structure affects the evolution of dispersal. For the aphid case study, I develop a Bayesian model of hierarchical multi-scale metapopulation dynamics, where the observed extinction and colonization rates are decomposed into intrinsic rates operating specifically at each spatial scale. In summary, I show how analytical approaches, hierarchical Bayesian methods and individual-based simulations can be used individually or in combination to tackle complex problems from many different viewpoints. In particular, hierarchical Bayesian methods provide a useful tool for decomposing ecological complexity into more tractable components.
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Erwinia carotovora subsp. carotovora is a bacterial phytopathogen that causes soft rot in various agronomically important crop plants. A genetically specified resistance to E. carotovora has not been defined, and plant resistance to this pathogen is established through nonspecific activation of basal defense responses. This, together with the broad host range, makes this pathogen a good model for studying the activation of plant defenses. Production and secretion of plant cell wall-degrading enzymes (PCWDE) are central to the virulence of E. carotovora. It also possesses the type III secretion system (TTSS) utilized by many Gram-negative bacteria to secrete virulence- promoting effector proteins to plant cells. This study elucidated the role of E. carotovora HrpN (HrpNEcc), an effector protein secreted through TTSS, and the contribution of this protein in the virulence of E. carotovora. Treatment of plants with HrpNEcc was demonstrated to induce a hypersensitive response (HR) as well as resistance to E. carotovora. Resistance induced by HrpNEcc required both salicylic acid (SA)- and jasmonate/ethylene (JA/ET)-dependent defense signaling in Arabidopsis. Simultaneous treatment of Arabidopsis with HrpNEcc and PCWDE polygalacturonase PehA elicited accelerated and enhanced induction of defense genes but also increased production of superoxide and lesion formation. This demonstrates mutual amplification of defense signaling by these two virulence factors of E. carotovora. Identification of genes that are rapidly induced in response to a pathogen can provide novel information about the early events occurring in the plant defense response. CHLOROPHYLLASE 1 (AtCLH1) and EARLY RESPONSIVE TO DEHYDRATION 15 (ERD15) are both rapidly triggered by E. carotovora in Arabidopsis. Characterization of AtCLH1 encoding chlorophyll-degrading enzyme chlorophyllase indicated that it might have a role in chlorophyll degradation during plant tissue damage. Silencing of this gene resulted in increased accumulation of reactive oxygen species (ROS) in response to pathogen infection in a light-dependent manner. This led to enhanced SA-dependent defenses and resistance to E. carotovora. Moreover, crosstalk between different defense signaling pathways was observed; JA-dependent defenses and resistance to fungal pathogen Alternaria brassicicola were impaired, indicating antagonism between SA- and JA-dependent signaling. Characterization of ERD15 suggested that it is a novel, negative regulator of abscisic acid (ABA) signaling in Arabidopsis. Overexpression of ERD15 resulted in insensitivity to ABA and reduced tolerance of the plants to dehydration stress. However, simultaneously, the resistance of the plants to E. carotovora was enhanced. Silencing of ERD15 improved freezing and drought tolerance of transgenic plants. This, together with the reducing effect of ABA on seed germination, indicated hypersensitivity to this phytohormone. ERD15 was hypothesized to act as a capacitor that controls the appropriate activation of ABA responses in Arabidopsis.
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Forestry has influenced forest dwelling organisms for centuries in Fennoscandia. For example, in Finland ca. 30% of the threatened species are threatened because of forestry. Nowadays forest management recommendations include practices aimed at maintaining biodiversity in harvesting, such as green-tree retention. However, the effects of these practices have been little studied. In variable retention, different numbers of trees are retained, varying from green-tree retention (at least a few live standing trees in clear-cuts) to thinning (only individual trees removed). I examined the responses of ground-dwelling spiders and carabid beetles to green-tree retention (with small and large tree groups), gap felling and thinning aimed at an uneven age structure of trees. The impacts of these harvesting methods were compared to those of clear-cutting and uncut controls. I aimed to test the hypothesis that retaining more trees positively affects populations of those species of spiders and carabids that were present before harvesting. The data come from two studies. First, spiders were collected with pitfall traps in south-central Finland in 1995 (pre-treatment) and 1998 (after-treatment) in order to examine the effects of clear-cutting, green-tree retention (with 0.01-0.02-ha sized tree groups), gap felling (with three 0.16-ha sized openings in a 1-ha stand), thinning aiming at an uneven age structure of trees and uncut control. Second, spiders and carabids were caught with pitfall traps in eastern Finland in 1998-2001 (pre-treatment and three post-treatment years) in eleven 0.09-0.55-ha sized retention-tree groups and clear-cuts adjacent to them. Original spider and carabid assemblages were better maintained after harvests that retained more trees. Thinning maintained forest spiders well. However, gap felling and large retention-tree groups maintained some forest spider and carabid species in the short-term, but negatively affected some species over time. However, use of small retention-tree groups was associated with negative effects on forest spider populations. Studies are needed on the long-term effects of variable retention on terrestrial invertebrates; especially those directed at defining appropriate retention patch size and on the importance of structural diversity provided by variable retention for invertebrate populations. However, the aims of variable retention should be specified first. For example, are retention-tree groups planned to constitute life-boats , stepping-stones or to create structural diversity? Does it suffice that some species are maintained, or do we want to preserve the most sensitive ones, and how are these best defined? Moreover, the ecological benefits and economic costs of modified logging methods should be compared to other approaches aimed at maintaining biodiversity.