Is a Majority Enough? Psychological Well-being and Its Relation to Academic and Prosocial Motivation, Self-regulation and Achievement at school

This cross-sectional study analyzed psychological well-being at school using the Self-Determination theory as a theoretical frame-work. The study explored basic psychological needs fulfillment (BPNS), academic (SRQ-A), prosocial self-regulation (SRQ-P) and motivation, and their relationship with achievement in general, special and selective education (N=786, 444 boys, 345 girls, mean age 12 yrs 8 mths). Motivation starts behavior which becomes guided by self-regulation. The perceived locus of control (PLOC) affects how self-determined this behavior will be; in other words, to what extent it is autonomously regulated. In order learn and thus to be able to accept external goals, a student has to feel emotionally safe and have sufficient ego-flexibility—all of which builds on satisfied psychological needs. In this study those conditions were explored. In addition to traditional methods Self-organizing maps (SOM), was used in order to cluster the students according to their well-being, self-regulation, motivation and achievement scores. The main impacts of this research were: a presentation of the theory based alternative of studying psychological well-being at school and usage of both the variable and person-oriented approach. In this Finnish sample the results showed that the majority of students felt well, but the well-being varied by group. Overall about for 11–15% the basic needs were deprived depending on the educational group. Age and educational group were the most effective factors; gender was important in relation to prosocial identified behavior. Although the person-oriented SOM-approach, was in a large extent confirming what was no-ticed by using comparison of the variables: the SEN groups had lower levels of basic needs fulfillment and less autonomous self-regulation, interesting deviations of that rule appeared. Some of the SEL- and GEN-group members ended up in the more unfavorable SOM-clusters, and not all SEN-group members belonged to the poorest clusters (although not to the best either). This evidence refines the well-being and self-regulation picture, and may re-direct intervention plans, and turn our focus also on students who might otherwise remain unnoticed. On the other hand, these results imply simultaneously that in special education groups the average is not the whole truth. On the basis of theoretical and empirical considerations an intervention model was sug-gested. The aim of the model was to shift amotivation or external motivation in a more intrinsic direction. According to the theoretical and empirical evidence this can be achieved first by studying the self-concept a student has, and then trying to affect both inner and environmental factors—including a consideration of the basic psychological needs. Keywords: academic self-regulation, prosocial self-regulation, basic psychological needs, moti-vation, achievement

University Students' Approaches to Learning, Self-Regulation, and Cognitive and Attributional Strategies : Connections with Well-Being and Academic Success

This dissertation empirically explores the relations among three theoretical perspectives: university students approaches to learning, self-regulated learning, as well as cognitive and attributional strategies. The relations were quantitatively studied from both variable- and person-centered perspectives. In addition, the meaning that students gave to their disciplinary choices was examined. The general research questions of the study were: 1) What kinds of relationships exist among approaches to learning, regulation of learning, and cognitive and attributional strategies? What kinds of cognitive-motivational profiles can be identified among university students, and how are such profiles related to study success and well-being? 3) How do university students explain their disciplinary choices? Four empirical studies addressed these questions. Studies I, II, and III were quantitative, applying self-report questionnaires, and Study IV was qualitative in nature. Study I explored relations among cognitive strategies, approaches to learning, regulation of learning, and study success by using correlations and a K-means cluster analysis. The participants were 366 students from various faculties at different phases of their studies. The results showed that all the measured constructs were logically related to each other in both variable- and person-centered approaches. Study II further examined what kinds of cognitive-motivational profiles could be identified among first-year university students (n=436) in arts, law, and agriculture and forestry. Differences in terms of study success, exhaustion, and stress among students with differing profiles were also looked at. By using a latent class cluster analysis (LCCA), three groups of students were identified: non-academic (34%), self-directed (35%), and helpless students (31%). Helpless students reported the highest levels of stress and exhaustion. Self-directed students received the highest grades. In Study III, cognitive-motivational profiles were identified among novice teacher students (n=213) using LCCA. Well-being, epistemological beliefs, and study success were looked at in relation to the profiles. Three groups of students were found: non-regulating (50%), self-directed (35%), and non-reflective (22%). Self-directed students again received the best grades. Non-regulating students reported the highest levels of stress and exhaustion, the lowest level of interest, and showed the strongest preference for certain and practical knowledge. Study IV, which was qualitative in nature, explored how first-year students (n = 536 ) in three fields of studies, arts, law, and veterinary medicine explained their disciplinary choices. Content analyses showed that interest appeared to be a common concept in students description of their choices across the three faculties. However, the objects of interest of the freshmen appeared rather unspecified. Veterinary medicine and law students most often referred to future work or a profession, whereas only one-fifth of the arts students did so. The dissertation showed that combining different theoretical perspectives and methodologies enabled us to build a rich picture of university students cognitive and motivational predispositions towards studying and learning. Further, cognitive-emotional aspects played a significant role in studying, not only in relation to study success, but also in terms of well-being. Keywords: approaches to learning, self-regulation, cognitive and attributional strategies, university students

Erityistä tukea tarvitsevan taaperon päiväkotiryhmään sopeutuminen : Monitapaustutkimus vuorovaikutussuhteista ja niiden rakentumisesta

How toddlers with special needs adjust to the daycare setting A multiple case study of how the relationships with adults and children are built The aim in this study is to describe how toddlers with special needs adjust to daycare. The emotional well-being and involvement in daycare activities of toddlers are especially investigated in this study. The relationship and how it is built between an adult and a child, a child and a child is examined. The daycare is examined through the socio-cultural theory as a pedagogical institution, where the child adapts by participating in social and cultural activities with the others. The development of the child is the result of the experiences that are gained through the constant relationship between the child, the family and social context. By the attachment theory the inner self-regulation, that allows the child safely adapt to new situations, develops most in the relationship between the child under 3years of age and the attending adult. The relationships between toddlers in daycare are usually built by the coincidental encounters in play and daily activities. In these relationships, the toddler gets the information of themselves and the other children. The complexity of the rules in the setting that organize the social action is challenging for the children and they need constant support from the adults. The participants of the study were five toddlers with special needs. When applying to daycare they were less than three years old and they got the specialist statement for their special needs, and the reference for daycare. The children were observed by recording their attending in the daycare once in the 3-4 months from the first day in daycare. Approximately 15 hours of material that was analysed with the Transana-program. The qualitative material was analysed by first collecting a descriptive model that explains and theorises the phenomenon. By the summery of the narrative it is placed a hypothesis that is tested by quantitative methods using correlations and variance analyses and general linear modeling that is used to count the differences between repeated measures and connections between different variables. The results of the study are built theoretically for the consistent conception between the theory and the findings in research. The toddlers in the study were all dependent on the support given by the adults in all the situations in the daycare. They could not associate with the other children without the support of the adults and their involvement in activities was low. The engagement of an adult in interaction was necessary for the children’s involvement in activities, and the co-operation with the other children. The engagement of teachers was statistically significantly higher than the engagement of other professions.

Regulating Food Consumption : Studies of change and variation in Europe

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

Onko eläimillä oikeuksia? : Eläinkoelainsäädännön kehitys ja nykytila

The use of animals in scientific experiments tends to arouse strong emotional reactions among the general public, the most essential concern being the pain and suffering they cause. It is felt that suffering inflicted on other beings, including animals, is not morally acceptable. Is the function of a researcher who uses animals morally acceptable and beneficial for humans and animals? May such a researcher him/herself decide what animal experiments he/she can perform or should some outsider have the right to decide what kind of experiments a researcher can or cannot perform? The research material comprises the legislation of Finland and that of some member and non-member states of the European Union, together with European Union directives and pertinent preparatory parliamentary documents. The author has likewise studied the vast literature on animal rights, both pro and contra writings and opinions. The opinions of philosophers on the moral and legal rights of animals are markedly conflicting. Some strongly support the existence of rights, while others totally refute such an opinion, claiming that the question is only of the moral principles of man himself which imply that animals must be treated in a human manner. Speaking of animal rights only tends to muddle ideas on the one hand in philosophical considerations and in legal analyses on the other. The development of legislation in Finland and some other member states of the European Union has in principle been similar. In Finland, the positive laws on animal experiments nowadays comply with the EU directive 86/609/EEC. However, there are marked differences between member states in respect of the way they have in practice implemented the principles of the EU directive. No essential alterations have in practice been discernible in the actual performance of animal experiments during the decades when legislation has been developed in different countries. Self-regulation within the scientific community has been markedly more effectual than legislative procedures. Legal regulation has nevertheless clearly influenced the quality of breeding and life conditions of experimental laboratory animals, cages for example being nowadays larger than hitherto. EU parliament and council have now accepted in September 2010 a new directive on animal experiments which must be implemented in the national legislations by January 1, 2013.

How can a Bourdieusian perspective aid the analysis of MBA education?

There is a lack of integrative conceptual models that would help to better understand the underlying reasons for the alleged problems of MBA education. To address this challenge, we draw on the work of Pierre Bourdieu to examine MBA education as an activity with its own ‘economy of exchange’ and ‘rules of the game.’ We argue that application of Bourdieu’s theoretical ideas elucidates three key issues in debate around MBA education: the outcomes of MBA programs, the inculcation of potentially problematic values and practices through the programs, and the potential of self-regulation such as accreditation and ranking for impeding development of MBA education. First, Bourdieu’s notions of capital – intellectual, social and symbolic – shed light on the ‘economy of exchange’ in MBA education. Critics of MBA programs have pointed out that the value of MBA degrees lies not only in ‘learning.’ Bourdieu’s framework allows further analysis of this issue by distinguishing between intellectual (learning), social (social networks), and symbolic capital (credentials and prestige). Second, the concept of ‘habitus’ suggests how values and practices are inculcated through MBA education. This process is often a ‘voluntary’ one where problematic or ethically questionable ideas may be regarded as natural. Third, Bourdieu’s reflections on the ‘doxa’ and its reproduction and legitimation illuminate the role of accreditation and ranking in MBA education. An analysis of such self-regulation explains in part how the system may turn out impeding change.

Oikeustieteen ensimmäisen vuoden opiskelijoiden haasteet opiskelussa

The aim of this dissertation was to explore factors which affect first-year law students study success. A modified Biggs s 3P model was used as the theoretical framework. The model includes both personal and contextual factors in student learning. The participants were first-year law students from the academic years 2005-2008, and the data were collected through interviews, open-ended question and electronic questionnaires. Study I explored first-year law students spontaneous descriptions of their learning activities at the beginning of their studies as well as fast study pace law students who had already finished their first year. Even though, law students are selected through a demanding entrance examination, some of the beginner students mentioned using only one or very few learning activities, which were mainly non-generative strategies. On the other hand, it was typical for the fast study pace students to mention generative strategies and elements of organised effort in studying. Study II analysed the relationship between approaches to learning and study success in terms of earned study credits and grade point average among first-year law students in three years. Organised students and students applying a deep approach earned the highest number of credits and the highest grades, whereas students applying a surface approach and unorganised students applying a deep approach received the lowest number of credits and the lowest grades. The study confirms previous findings that organised students constitute the largest cluster among first-year law students. Study III explored factors affecting the study pace of law students during their first academic year. The factors mentioned by the students were classified into four categories of self-regulation: motivation, behaviour, cognition and context. The group of fast study pace students turned out to have good skills in all areas of self-regulation. Respectively, the slow study pace group showed more individual variation, and had weaknesses in one or more areas of self-regulation. In addition, students experienced, that other activities such as working affected their study pace, this could be constitute a fifth category. However, the slow and fast study pace students felt differently about work. According to the slow study pace students, work impeded their studying because it took up too much time. For their part, the fast study pace students were able to allocate their time effectively and felt working to be useful and a counterbalanced to their studying, as well as an opportunity to apply knowledge in practice. Study IV analysed differences in law students perceptions of their teaching-learning environments after three learning periods. The students perceptions were compared with pharmacy and veterinary students perceptions of their teaching-learning environments. The results showed that the law students experienced their teaching-learning environment more negatively than the pharmacy and veterinary students. The law students experienced that alignment, teaching for understanding, staff enthusiasm and support, along with constructive feedback were areas that could be developed at the Faculty. Together the four studies indicate that both law students learning skills and the teaching-learning environment could be further developed. The results imply that managing in the demanding teaching-learning environment of law requires student to effectively employ qualitative learning activities: organised studying and a deep approach to learning and good self-regulation skills. In addition to student counselling, it is important for students study success to direct the teaching-learning environment towards a more learning-focused than content-focused approach to teaching.

Dimensions of University Student Learning in Medicine and Pharmacy

Study orientations in higher education consist of various dimensions, such as approaches to learning, conceptions of learning and knowledge (i.e. epistemologies), self-regulation, and motivation. They have also been measured in different ways. The main orientations typically reported are reproducing and meaning orientations. The present study explored dimensions of study orientations, focusing in particular on pharmacy and medicine. New versions of self-report instruments were developed and tested in various contexts and in two countries. Furthermore, the linkages between study orientations and students epistemological development were explored. The context of problem-based (PBL) small groups was investigated in order to better understand how collaboration contributes to the quality of learning. The participants of Study I (n=66) were pharmacy students, who were followed during a three-year professionally oriented program in terms of their study orientations and epistemologies. A reproducing orientation to studying diminished during studying, whereas only a few students maintained their original level of meaning orientation. Dualism was found to be associated with a reproducing orientation. In Study II practices associated with deep and surface approaches to learning were measured in two differing ways, in order to better distinguish between what students believed to be useful in studying, and the extent to which they applied their beliefs to practice when preparing for examinations. Differences between domains were investigated by including a sample of Finnish and Swedish medical students (n=956) and a Finnish non-medical sample of university students (n=865). Memorizing and rote learning appeared as differing components of a surface approach to learning, while understanding, relating, and critical evaluation of knowledge emerged as aspects of a deep approach to learning. A structural model confirmed these results in both student samples. Study III explored a wide variety of dimensions of learning in medical education. Swedish medical students (n=280) answered the questionnaire. The deep approach to learning was strongly related to collaboration and reflective learning, whereas the surface approach was associated with novice-like views of knowledge and the valuing of certain and directly applicable knowledge. PBL students aimed at understanding, but also valued the role of memorization. Study IV investigated 12 PBL tutorial groups of students (n=116) studying microbiology and pharmacology in a medical school. The educational application was expected to support a deep approach to learning: Group members course grades in a final examination were related to the perceived functioning of the PBL tutorial groups. Further, the quality of cases that had been used as triggers for learning, was associated with the quality of small group functioning. New dimensions of study orientations were discovered. In particular, novel, finer distinctions were found within the deep approach component. In medicine, critical evaluation of knowledge appeared to be less valued than understanding and relating. Further, collaboration appeared to be closely related to the deep approach, and it was also important in terms of successful PBL studying. The results of the studies confirmed the previously found associations between approaches to learning and study success, but showed interesting context- and subgroup-related differences in this respect. Students ideas about the nature of knowledge and their approaches to learning were shown to be closely related. The present study expanded our understanding of the dimensions of study orientations, of their development, and their contextual variability in pharmacy and medicine.

Kiinnostusta vai ahdistusta? : Opettajaksi opiskelevien akateemiset tunteet, motivaatio ja opiskelun ongelmat suhteessa hyvinvointiin ja menestykseen aktivoivalla luentokurssilla

Previous studies indicate that positive learning experiences are related to academic achievement as well as to well-being. On the other hand, emotional and motivational problems in studying may pose a risk for both academic achievement and well-being. Thus, emotions and motivation have an increasing role in explaining university students learning and studying. The relations between emotions, motivation, study success and well-being have been less frequently studied. The aim of this study was to investigate what kind of academic emotions, motivational factors and problems in studying students experienced five days before an exam of an activating lecture course, and the relations among these factors as well as their relation to self-study time and study success. Furthermore, the effect of all these factors on well-being, flow experience and academic achievement was examined. The term academic emotion was defined as emotion experienced in academic settings and related to studying. In the present study the theoretical background to motivational factors was based on thinking strategies and attributions, flow experience and task value. Problems in studying were measured in terms of exhaustion, anxiety, stress, lack of interest, lack of self-regulation and procrastination. The data were collected in December 2009 in an activating educational psychology lecture course by using a questionnaire. The participants (n=107) were class and kindergarten teacher students from the University of Helsinki. Most of them were first year students. The course grades were also gathered. Correlations and stepwise regression analysis were carried out to find out the factors that were related to or explained study success. The clusters that presented students´ problems in studying as well as thinking strategies and attributions, were found through hierarchical cluster analysis. K-means cluster analysis was used to form the final groups. One-way analysis of variance, Kruskal-Wallis test and crosstabs were conducted to see whether the students in different clusters varied in terms of study success, academic emotions, task value, flow, and background variables. The results indicated that academic emotions measured five days before the exam explained about 30 % of the variance of the course grade; exhaustion and interest positively, and anxiety negatively. In addition, interest as well as the self-study time best explained study success on the course. The participants were classified into three clusters according to their problems in studying as well as their thinking strategies and attributions: 1) ill-being, 2) carefree, and 3) committed and optimistic students. Ill-being students reported most negative emotions, achieved the worst grades, experienced anxiety rather than flow and were also the youngest. Carefree students, on the other hand, expressed the least negative emotions and spent the least time on self-studying, and like committed students, experienced flow. In addition, committed students reported positive emotions the most often and achieved the best grades on the course. In the future, more in-depth understanding how and why especially young first year students experience their studying hard is needed, because early state of the studies is shown to predict later study success.

From neural stem cells to precursors : Molecular regulation of self-renewal and differentiation

Stem cells are responsible for tissue turnover throughout lifespan. Only highly controlled specific environment, the stem cell niche , can sustain undifferentiated stem cell-pool. The balance between maintenance and differentiation is crucial for individual s health: uncontrolled stem cell self-renewal or proliferation can lead to hyperplasia and mutations that further provoke malignant transformation of the cells. On the other hand, uninhibited differentiation may result in diminished stem cell population, which is unable to maintain tissue turnover. The mechanisms that control the switch from maintenance to differentiation in stem cells are not well known. The same mechanisms that direct the self-renewal and proliferation in normal stem cells are likely to be also involved in maintenance of cancer stem cell . Cancer stem cells exhibit stem cell like properties such as self-renewal- and differentiation capacity and they can also regenerate the tumor tissue. In this thesis, I have investigated the effect of classical oncogenes E6/E7 and c-Myc, tumor suppressors p53 and retinoblastoma (pRb) family, and vascular endothelial growth factor (VEGF) subfamily and glial cell line-derived neurothropic factor (GDNF) family ligands on behavior of embryonic neural stem cells (NSCs) and progenitors. The study includes also the characterization of cytoskeletal tumor suppressor neurofibromatosis 2 (NF2) protein merlin and ezrin-radixin-moesin (ERM) protein ezrin expression in neural progenitors cells and their progeny. This study reveals some potential mechanisms regarding to NSCs maintenance. In summary, the studied molecules are able to shift the balance either towards stem cell maintenance or differentiation; tumor suppressor p53 represses whereas E6/E7 oncogenes and c-Myc increase the proportion of self-renewing and proliferating NSCs or progenitors. The data suggests that active MEK-ERK signaling is critical for self-renewal of normal and oncogene expressing NSCs. In addition, the results indicate that expression of cytoskeletal tumor suppressor merlin and ERM protein ezrin in central nervous system (CNS) tissue and progenitors indicates their role in cell differentiation. Furthermore, the data suggests that VEGF-C a factor involved in lymphatic system development, angiogenesis, neovascularization and metastasis but also in maintenance of some neural populations in brain is a novel thropic factor for progenitors in early sympathetic nervous system (SNS). It seems that VEGF-C dose dependently through ERK-pathway supports the proliferation and survival of early sympathetic progenitor cells, and the effect is comparable to that of GDNF family ligands.

Hematopoietic Stem Cell Development and Transcriptional Regulation

The continuous production of blood cells, a process termed hematopoiesis, is sustained throughout the lifetime of an individual by a relatively small population of cells known as hematopoietic stem cells (HSCs). HSCs are unique cells characterized by their ability to self-renew and give rise to all types of mature blood cells. Given their high proliferative potential, HSCs need to be tightly regulated on the cellular and molecular levels or could otherwise turn malignant. On the other hand, the tight regulatory control of HSC function also translates into difficulties in culturing and expanding HSCs in vitro. In fact, it is currently not possible to maintain or expand HSCs ex vivo without rapid loss of self-renewal. Increased knowledge of the unique features of important HSC niches and of key transcriptional regulatory programs that govern HSC behavior is thus needed. Additional insight in the mechanisms of stem cell formation could enable us to recapitulate the processes of HSC formation and self-renewal/expansion ex vivo with the ultimate goal of creating an unlimited supply of HSCs from e.g. human embryonic stem cells (hESCs) or induced pluripotent stem cells (iPS) to be used in therapy. We thus asked: How are hematopoietic stem cells formed and in what cellular niches does this happen (Papers I, II)? What are the molecular mechanisms that govern hematopoietic stem cell development and differentiation (Papers III, IV)? Importantly, we could show that placenta is a major fetal hematopoietic niche that harbors a large number of HSCs during midgestation (Paper I)(Gekas et al., 2005). In order to address whether the HSCs found in placenta were formed there we utilized the Runx1-LacZ knock-in and Ncx1 knockout mouse models (Paper II). Importantly, we could show that HSCs emerge de novo in the placental vasculature in the absence of circulation (Rhodes et al., 2008). Furthermore, we could identify defined microenvironmental niches within the placenta with distinct roles in hematopoiesis: the large vessels of the chorioallantoic mesenchyme serve as sites of HSC generation whereas the placental labyrinth is a niche supporting HSC expansion (Rhodes et al., 2008). Overall, these studies illustrate the importance of distinct milieus in the emergence and subsequent maturation of HSCs. To ensure proper function of HSCs several regulatory mechanisms are in place. The microenvironment in which HSCs reside provides soluble factors and cell-cell interactions. In the cell-nucleus, these cell-extrinsic cues are interpreted in the context of cell-intrinsic developmental programs which are governed by transcription factors. An essential transcription factor for initiation of hematopoiesis is Scl/Tal1 (stem cell leukemia gene/T-cell acute leukemia gene 1). Loss of Scl results in early embryonic death and total lack of all blood cells, yet deactivation of Scl in the adult does not affect HSC function (Mikkola et al., 2003b. In order to define the temporal window of Scl requirement during fetal hematopoietic development, we deactivated Scl in all hematopoietic lineages shortly after hematopoietic specification in the embryo . Interestingly, maturation, expansion and function of fetal HSCs was unaffected, and, as in the adult, red blood cell and platelet differentiation was impaired (Paper III)(Schlaeger et al., 2005). These findings highlight that, once specified, the hematopoietic fate is stable even in the absence of Scl and is maintained through mechanisms that are distinct from those required for the initial fate choice. As the critical downstream targets of Scl remain unknown, we sought to identify and characterize target genes of Scl (Paper IV). We could identify transcription factor Mef2C (myocyte enhancer factor 2 C) as a novel direct target gene of Scl specifically in the megakaryocyte lineage which largely explains the megakaryocyte defect observed in Scl deficient mice. In addition, we observed an Scl-independent requirement of Mef2C in the B-cell compartment, as loss of Mef2C leads to accelerated B-cell aging (Gekas et al. Submitted). Taken together, these studies identify key extracellular microenvironments and intracellular transcriptional regulators that dictate different stages of HSC development, from emergence to lineage choice to aging.