986 resultados para Vice.


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Your money or your life? A qualitative follow-up study of the young unemployed from an actor perspective is a qualitative and longitudinal study following 36 unemployed young people in Helsinki over a span of ten years. The purpose of the study is to shed light on how a few young people view employment/unemployment and their lives and future, how they as unemployed perceive their encounters with society, and how society supports them. Four so-called key informants were followed at a finer level of empirical detail. They were chosen for the thematic interviews because of their different personalities, starting points and preferences. Although some differences were expected, what the results show is quite striking. The individual stories raise a number of questions about differences between young people, about society s view of the young unemployed, and about the principles behind the so-called activation policy and how society s support is distributed. The key informants descriptions underline that the group young unemployed does not consist of individuals who are alike but that life is complex, that paid work and unemployment can be perceived very differently, and that background and unofficial support can have consequences for self-perception and for ways of looking at the future, vocational choices, paid work and activation policy. Margaret S. Archer s theory of Morphogenesis and Barbara Cruikshank s theory of constructing democracies compose the study s theoretical framework. The key informants stories give a picture of a formal support system that, even though it puts part of the responsibility for unemployment on the individuals themselves, in the name of fairness and equality, treats them in an impersonal way, not giving their personal situation and wishes much weight. As a consequence, those who share the dominant values of society do well, while others who do not are faced with difficulties. The bigger the gap between society s and the individual s values, the bigger the risk to be met by little understanding and by penalties. And vice versa: Those who initially have the right values and know how to deal with authorities get heard and their opinions get accepted. The informants ask for a more personal encounter, which could improve both the atmosphere and the clients experiences of being heard. Still the risk of having a more individualistic system should be addressed, as a new system might generate new winners, but just as well give new losers. Finally, we have to ask if the so-called activation policy is looking for answers primarily to a macro-level problem on the micro-level. If it does not produce more jobs, its support for the unemployed will be insignificant. It is not enough to think about what to do at the grassroots level to make the system more functional and support job-seeking. If the current rate of unemployment endures, the quality of life of the unemployed should be addressed. A first step could be taken by placing less guilt on the unemployed. Instead of talking about activating the unemployed, discussion should be targeted at removing structural impediments to employment. If we want to have less polarisation between the those with paid work and those without, who often struggle with low incomes, we need to include the macro-level in the discussion. What does high unemployment mean in a work-based society, where the individual s self-perception and important social forms of support are linked to labour income? And what can be done at the macro-level to change this undesirable condition at the micro-level? Keywords: Unemployment, Youth, Public interventions, Activation policy, Individual actors, Qualitative, Longitudinal, Holistic, Helsinki, Finland

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The endoplasmic reticulum (ER) and the Golgi apparatus are organelles that produce, modify and transport proteins and lipids and regulate Ca2+ environment within cells. Structurally they are composed of sheets and tubules. Sheets may take various forms: intact, fenestrated, single or stacked. The ER, including the nuclear envelope, is a single continuous network, while the Golgi shows only some level of connectivity. It is often unclear, how different morphologies correspond to particular functions. Previous studies indicate that the structures of the ER and Golgi are dynamic and regulated by fusion and fission events, cytoskeleton, rate of protein synthesis and secretion, and specific structural proteins. For example, many structural proteins shaping tubular ER have been identified, but sheet formation is much more unclear. In this study, we used light and electron microscopy to study morphological changes of the ER and Golgi in mammalian cells. The proportion, type, location and dynamics of ER sheets and tubules were found to vary in a cell type or cell cycle stage dependent manner. During interphase, ER and Golgi structures were demonstrated to be regulated by p37, a cofactor of the fusion factor p97, and microtubules, which also affected the localization of the organelles. Like previously shown for the Golgi, the ER displayed a tendency for fenestration and tubulation during mitosis. However, this shape change did not result in ER fragmentation as happens to Golgi, but a continuous network was retained. The activity of p97/p37 was found to be important for the reassembly of both organelles after mitosis. In EM images, ER sheet membranes appear rough, since they contain attached ribosomes, whereas tubular membranes appear smooth. Our studies revealed that structural changes of the ER towards fenestrated and tubular direction correlate with loss of ER-bound ribosomes and vice versa. High and low curvature ER membranes have a low and high density of ribosomes, respectively. To conclude, both ER and Golgi architecture depend on fusion activity of p97/p37. ER morphogenesis, particularly of the sheet shape, is intimately linked to the density of membrane bound ribosomes.

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Among Girls Youth Work, Multiculturalism and Gender Equality Finland s increasingly multicultural society concerns younger generations in a very particular manner. Starting already in pre-school kindergartens, children from different cultural backgrounds share their everyday existence. The focus of this study is Finland s increasingly multicultural society that has challenged youth work professionals in particular and made them rethink questions related to content, basic values and goals of youth work. These reconsiderations include the following essential questions: which of these pedagogic principles are defined as Finnish, and under what kinds of circumstances would the youth workers be ready to negotiate about them. These questions, which are related to multiculturalism, are then linked to the girls position, status and gender equality. The research examines how gender equality is articulated in relation to multiculturalism and vice versa, in what contexts youth work-related questions are negoatiated in, and how these negotiations then relate to gender issues. The present study combines theoretical concepts and debates from both post-colonial and youth research, and has benefited greatly from previous research which has examined the everyday lives of young people with multicultural backgrounds and conceptualised the different meanings of age, ethnicity, culture and gender. Neither multiculturalism nor gender equality is, however, taken as a given concept in this study; rather the research focuses on how youth workers understand and define these concepts and how they are used. The emphasis has been on monitoring the varying consequences of different understandings and definitions in terms of everyday work and practices. The goal of this study has been to find typical ways of conceptualising multiculturalism, gender equality and the role of girls in the context of youth work. The focus of the research is not just the youth workers different views but also the notions of the girls themselves. These are then further analysed by examining the ways the girls negotiate their agency. Examples of how the girls agency is defined and the different forms of agency that are offered to the girls within the context of leisure time activities and youth work have been sought. The kind of agency the girls then assume is also examined. The data in this research is comprised of interviews with young people with multicultural backgrounds (n=39), youth workers (n=42) and of ethnographic fieldwork (2003 2005). The fieldwork concentrated on following different types of youth work activities that were targeted at girls with migrant backgrounds. These were organized both by selected municipalities and NGOs. The research shows that various questions related to multicultural issues have enhanced the visibility of gender equality in the field of youth work. The identification of gender-based inequality is especially closely linked to the position of girls from migrant backgrounds. These girls are a source of particular worry and the aim of the many activity groups for migrant girls is to educate them so that they can become equal Finnish citizens . The youth work itself is seen as gender-neutral and equality based. Equality in this context is defined as a purely quantitative concept, and the solution to any possible inequalities is thus the exact same treatment for everyone . The girls themselves seem mainly confused by the role that is offered to them. They would need a voice and the possibility to have an impact on the planning of youth work activities. They want to have their views heard. The role of the victim assigned to them is very confining and makes it difficult to act. At the same time the research shows how gender-sensitive youth work is seen to mean youth work with girls. Gender-sensitive work with boys is not really done or is done very little, even if many of the interviewees are of the opinion that the true materialization of gender equality would require boys to be taken into account too. The principle of gender equality should be shared by the entire youth work profession. Keywords Youth work, equality, multiculturalism, gender sensitivity, agency, girls, young people, sexuality

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The effects of power-law plasticity (yield strength and strain hardening exponent) on the plastic strain distribution underneath a Vickers indenter was systematically investigated by recourse to three-dimensional finite element analysis, motivated by the experimental macro-and micro-indentation on heat-treated Al-Zn-Mg alloy. For meaningful comparison between simulated and experimental results, the experimental heat treatment was carefully designed such that Al alloy achieve similar yield strength with different strain hardening exponent, and vice versa. On the other hand, full 3D simulation of Vickers indentation was conducted to capture subsurface strain distribution. Subtle differences and similarities were discussed based on the strain field shape, size and magnitude for the isolated effect of yield strength and strain hardening exponent.

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Multiple Perspectives on Networks: Conceptual Development, Application and Integration in an Entrepreneurial Context. The purpose of this thesis is to enhance cross-fertilization between three different approaches to network research. The business network approach may contribute in terms of how relationships are created, developed and how tie content changes within ties, not only between them. The social network approach adds to the discussion by offering concepts of structural change on a network level. The network approach in entrepreneurship contributes by emphasizing network content, governance and structure as a way of understanding and capturing networks. This is discussed in the conceptual articles, Articles 2 and 3. The ultimate purpose of this thesis is to develop a theoretical and empirical understanding of network development processes. This is fulfilled by presenting a theoretical framework, which offers multiple views on process as a developmental outcome. The framework implies that change ought to be captured both within and among relationships over time in the firm as well as in the network. Consequently, changes in structure and interaction taking place simultaneously need to be included when doing research on network development. The connection between micro and macro levels is also stressed. Therefore, the entrepreneur or firm level needs to be implemented together with the network level. The surrounding environment impacts firm and network development and vice versa and hence needs to be integrated. Further, it is necessary to view network development not only as a way forward but to include both progression and regression as inevitable parts of the process. Finally, both stability and change should be taken into account as part of network development. Empirical results in Article 1 show support for a positive impact of networks on SME internationalization. Article 4 compares networks of novice, serial and portfolio entrepreneurs but the empirical results show little support for differences in the networks by type of entrepreneur. The results demonstrate that network interaction and structure is not directly impacted by type of entrepreneur involved. It indicates instead that network structure and interaction is more impacted by the development phase of the firm. This in turn is in line with the theoretical implications, stating that the development of the network and the firm impacts each other, as they co-evolve.

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This paper examines the relationships between uncertainty and the perceived usefulness of traditional annual budgets versus flexible budgets in 95 Swedish companies. We form hypotheses that the perceived usefulness of the annual budgets as well as the attitudes to more flexible budget alternatives are influenced by the uncertainty that the companies face. Our study distinguishes between two separate kinds of uncertainty: exogenous stochastic uncertainty (deriving from the firm’s environment) and endogenous deterministic uncertainty (caused by the strategic choices made by the firm itself). Based on a structural equations modelling analysis of data from a mail survey we found that the more accentuated exogenous uncertainty a company faces, the more accentuated is the expected trend towards flexibility in the budget system, and vice versa; the more endogenous uncertainty they face, the more negative are their attitudes towards budget flexibility. We also found that these relationships were not present with regard to the attitudes towards the usefulness of the annual budget. Noteworthy is, however, that there was a significant negative relationship between the perceived usefulness of the annual budget and budget flexibility. Thus, our results seem to indicate that the degree of flexibility in the budget system is influenced by both general attitudes towards the usefulness of traditional budgets and by the actual degree of exogenous uncertainty a company faces and by the strategy that it executes.

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Reconstructions in optical tomography involve obtaining the images of absorption and reduced scattering coefficients. The integrated intensity data has greater sensitivity to absorption coefficient variations than scattering coefficient. However, the sensitivity of intensity data to scattering coefficient is not zero. We considered an object with two inhomogeneities (one in absorption and the other in scattering coefficient). The standard iterative reconstruction techniques produced results, which were plagued by cross talk, i.e., the absorption coefficient reconstruction has a false positive corresponding to the location of scattering inhomogeneity, and vice-versa. We present a method to remove cross talk in the reconstruction, by generating a weight matrix and weighting the update vector during the iteration. The weight matrix is created by the following method: we first perform a simple backprojection of the difference between the experimental and corresponding homogeneous intensity data. The built up image has greater weightage towards absorption inhomogeneity than the scattering inhomogeneity and its appropriate inverse is weighted towards the scattering inhomogeneity. These two weight matrices are used as multiplication factors in the update vectors, normalized backprojected image of difference intensity for absorption inhomogeneity and the inverse of the above for the scattering inhomogeneity, during the image reconstruction procedure. We demonstrate through numerical simulations, that cross-talk is fully eliminated through this modified reconstruction procedure.

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The triangular space between memory, narrative and pictorial representation is the terrain on which this article is developed. Taking the art of memory developed by Giordano Bruno (1548 – 1600) and the art of painting subtly revolutionised by Adam Elsheimer (1578 – 1610) as test-cases, it is shown how both subvert the norms of mimesis and narration prevalent throughout the Renaissance, how disrupted memory creates “incoherent” narratives, and how perspective and the notion of “place” are questioned in a corollary way. Two paintings by Elsheimer are analysed and shown to include, in spite of their supposed “realism”, numerous incoherencies, aporias and strange elements – often overlooked. Thus, they do not conform to two of the basic rules governing both the classical art of memory and the humanist art of painting: well-defined places and the exhaustive translatability of words into images (and vice-versa). In the work of Bruno, both his philosophical claims and the literary devices he uses are analysed as hints for a similar (and contemporaneous) undermining of conventions about the transparency and immediacy of representation.

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Pragmatism has sometimes been taken as a catchphrase for epistemological stances in which anything goes. However, other authors argue that the real novelty and contribution of this tradition has to do with its view of action as the context in which all things human take place. Thus, it is action rather than, for example, discourses that should be our starting point in social theory. The introductory section of the book situates pragmatism (especially the ideas of G. H. Mead and John Dewey) within the field and tradition of social theory. This introductory also contextualizes the main core of the book which consists of four chapters. Two of these chapters have been published as articles in scientific journals and one in an edited book. All of them discuss the core problem of social theory: how is action related to social structures (and vice versa)? The argument is that habitual action is the explanation for the emergence of social structures from our action. Action produces structures and social reproduction takes place when action is habitualized; that is, when we develop social dispositions to act in a certain manner in familiar environments. This also means that even though the physical environment is the same for all of us, our habits structure it into different kinds of action possibilities. Each chapter highlights these general insights from different angles. Practice theory has gained momentum in recent years and it has many commonalities with pragmatism because both highlight the situated and corporeal character of human activity. One famous proponent of practice theory is Margaret Archer who has argued that the pragmatism of G. H. Mead leads to an oversocialized conception of selfhood. Mead does indeed present a socialized view of selfhood but this is a meta-sociological argument rather than a substantial sociological claim. Accordingly, one can argue that in this general sense intersubjectivity precedes subjectivity and not the other way around. Such a view does not indicate that our social relation would necessarily "colonize" individual action because there is a place for internal conversations (in Archer s terminology); it is especially in those phases of action where it meets obstacles due to the changes of the environment. The second issue discussed has the background assumption that social structures can fruitfully be conceptualized as institutions. A general classification of different institution theories is presented and it is argued that there is a need for a habitual theory of institutions due to the problems associated with these other theories. So-called habitual institutionalism accounts for institutions in terms of established and prevalent social dispositions that structure our social interactions. The germs of this institution theory can be found in the work of Thorstein Veblen. Since Veblen s times, these ideas have been discussed for example, by the economist Geoffrey M. Hodgson. His ideas on the evolution of institutions are presented but a critical stance is taken towards his tendency of defining institutions with the help of rules because rules are not always present in institutions. Accordingly, habitual action is the most basic but by no means the only aspect of institutional reproduction. The third chapter deals with theme of action and structures in the context of Pierre Bourdieu s thought. Bourdieu s term habitus refers to a system of dispositions which structure social fields. It is argued that habits come close to the concept of habitus in the sense that the latter consists of particular kinds of habits; those that are related to the reproduction of socioeconomic positions. Habits are thus constituents of a general theory of societal reproduction whereas habitus is a systematic combination of socioeconomic habits. The fourth theme relates to issues of social change and development. The capabilities approach has been associated with the name of Amartya Sen, for example, and it underscores problems inhering in economistic ways of evaluating social development. However, Sen s argument has some theoretical problems. For example, his theory cannot adequately confront the problem of relativism. In addition, Sen s discussion lacks also a theory of the role of the public. With the help of arguments derived from pragmatism, one gets an action-based, socially constituted view of freedom in which the role of the public is essential. In general, it is argued that a socially constituted view of agency does not necessarily to lead to pessimistic conclusions about the freedom of action.

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Tutkimuksessa tarkastellaan äänestäjien talouskäsitysten vaikutusta hallituksen suosioon Puolassa vuosina 2006 ja 2007. Tutkimusasetelma juontaa juurensa poliittisten suhdannevaihteluiden teoriaan, jonka mukaan poliitikot pyrkivät manipuloimaan taloutta vaalien alla tullakseen uudelleen valituiksi. Vastuullisuushypoteesin mukaan äänestäjät palkitsevat poliitikot hyvästä taloustilanteesta. Näin ollen mikäli äänestäjät ovat tyytyväisiä talouteen he äänestävät hallitusta. Mikäli eivät, he äänestävät oppositiota. Miten äänestäjät sitten tekevät arvionsa taloudesta? Tutkielmassa selvitetään vaikuttiko äänestäjien mielipiteisiin käsitys nykyisestä vai tulevaisuuden taloustilanteesta. Käsitys nykyisestä taloustilanteesta perustuu havaintoihin jo toteutuneesta talouspolitiikasta. Tätä käsitystä kutsutaan retrospektiiviseksi näkemykseksi. Prospektiiviset talousnäkemykset koostuvat näkemyksestä ja odotuksista talouden tulevasta tilasta ja uskosta hallituksen kykyyn tarjota paras vaihtoehto suotuisalle talouskehitykselle. Aikaulottuvuuden lisäksi tutkielmassa testataan, vaikuttaako äänestäjiin enemmän heidän oma taloustilanteensa vai näkemys yleisestä talouden tilanteesta. Mikäli hallituksen suosio perustuu näkemyksiin henkilökohtaisen talouden tilasta, ovat äänestäjät egotrooppisia. Mikäli kannatuspäätös perustuu näkemykseen kansantalouden tilasta, ovat äänestäjät puolestaan sosiotrooppisia. Aineistona tutkielmassa käytetään uusinta saatavilla olevaa Puolan mielipidetiedustelun (Centrum Badania Opinii Publicznej) keräämää kyselyaineistoa vuosilta 2006 ja 2007. Tutkielmassa on yhdistetty kyselyaineistot 22:n kuukauden ajalta. Aineistoa on analysoitu logistisen regressioanalyysin menetelmin. Tutkielman perusteella talousnäkemyksistä suurin vaikutus hallituksen suosioon on äänestäjien näkemyksillä kansantalouden tulevaisuuden tilasta. Henkilökohtaisen talouden osalta positiiviset tulevaisuudennäkymät vaikuttavat positiivisesti myös hallituksen kannatukseen. Retrospektiivinen arvio henkilökohtaisesta taloudesta toimii kuitenkin teorian vastaisesti; oman taloudellisen tilanteen hyväksi arvioineiden todennäköisyys kannatta hallitusta oli pienempää kuin niillä, jotka arvioivat oman taloustilanteensa huonoksi. Kontrollimuuttujiksi valittiin joukko aiemmassa tutkimuksessa äänestyskäyttäytymiseen Puolassa vaikuttaneita tekijöitä. Näitä olivat ikä, sukupuoli, koulutus, asuinpaikka, näkemys työllisyystilanteesta, ideologinen sijoittuminen oikeisto–vasemmisto-akselilla sekä uskonnollisuus. Kontrollimuuttujista merkitseviksi osoittautuivat uskonnollisuus, oikeisto–vasemmisto-ideologia, koulutus, asuinpaikka sekä ikä. Kun edellä mainitut taustamuuttujat on kontrolloitu, taloustekijät selittävät noin viidesosan hallituksen kannatuksen todennäköisyyden vaihtelusta.

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This thesis explores the particular framework of evidentiary assessment of three selected appellate national asylum procedures in Europe and discusses the relationship between these procedures, on the one hand, and between these procedures and other legal systems, including the EU legal order and international law, on the other. A theme running throughout the thesis is the EU strivings towards approximation of national asylum procedures and my study analyses the evidentiary assessment of national procedures with the aim of pinpointing similarities and differences, and the influences which affect these distinctions. The thesis first explores the frames construed for national evidentiary solutions by studying the object of decision-making and the impact of legal systems outside the national. Second, the study analyses the factual evidentiary assessment of three national procedures - German, Finnish and English. Thirdly, the study explores the interrelationship between these procedures and the legal systems influencing them and poses questions in relation to the strivings of EU and methods of convergence. The thesis begins by stating the framework and starting points for the research. It moves on to establish keys of comparison concerning four elements of evidentiary assessment that are of importance to any appellate asylum procedure, and that can be compared between national procedures, on the one hand, and between international, regional and national frameworks, on the other. Four keys of comparison are established: the burden of proof, demands for evidentiary robustness, the standard of proof and requirements for the methods of evidentiary assessment. These keys of comparison are then identified in three national appellate asylum procedures, and in order to come to conclusions on the evidentiary standards of the appellate asylum procedures, relevant elements of the asylum procedures in general are presented. Further, institutional, formal and procedural matters which have an impact on the evidentiary standards in the national appellate procedures are analysed. From there, the thesis moves on to establish the relationship between national evidentiary standards and the legal systems which affect them, and gives reasons for similarities and divergences. Further, the thesis studies the impact of the national frameworks on the regional and international level. Lastly, the dissertation makes a de lege ferenda survey of the relationship between EU developments, the goal of harmonization in relation to national asylum procedures and the particular feature of evidentiary standards in national appellate asylum procedures. Methodology The thesis follows legal dogmatic methods. The aim is to analyse legal norms and legal constructions and give them content and context. My study takes as its outset an understanding of the purposes for legal research also regarding evidence and asylum to determine the contents of valid law through analysis and systematization. However, as evidentiary issues traditionally are normatively vaguely defined, a strict traditional normative dogmatic approach is not applied. For the same reason a traditionalist and strict legal positivism is not applied. The dogmatics applied to the analysis of the study is supported by practical analysis. The aim is not only to reach conclusions concerning the contents of legal norms and the requirements of law, but also to study the use and practical functioning of these norms, giving them a practcial context. Further, the study relies on a comparative method. A functionalist comparative method is employed and keys of comparison are found in evidentiary standards of three selected national appellate asylum procedures. The functioning equivalences of German, Finnish and English evidentiary standards of appellate asylum procedures are compared, and they are positioned in an European and international legal setting. Research Results The thesis provides results regarding the use of evidence in national appellate asylum procedures. It is established that evidentiary solutions do indeed impact on the asylum procedure and that the results of the procedure are dependent on the evidentiary solutions made in the procedures. Variations in, amongst other things, the interpretation of the burden of proof, the applied standard of proof and the method for determining evidentiary value, are analysed. It is established that national impacts play an important role in the adaptation of national appellate procedures to external requirements. Further, it is established that the impact of national procedures on as well the international framework as on EU law varies between the studied countries, partly depending on the position of the Member State in legislative advances at the EU level. In this comparative study it is, further, established that the impact of EU requirements concerning evidentiary issues may be have positive as well as negative effects with regard to the desired harmonization. It is also concluded that harmonization using means of convergence that primaly target legal frameworks may not in all instances be optimal in relation to evidentiary standards, and that more varied and pragmatic means of convergence must be introduced in order to secure harmonization also in terms of evidence. To date, legal culture and traditions seem to prevail over direct efforts at procedural harmonization.

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Cancer cells are often associated with secondary chromosomal rearrangements, such as deletions, inversions, and translocations, which could be the consequence of unrepaired/misrepaired DNA double strand breaks (DSBs). Nonhomologous DNA end joining is one of the most common pathways to repair DSBs in higher eukaryotes. By using oligomeric DNA substrates mimicking various endogenous DSBs in a cell-free system, we studied end joining (EJ) in different cancer cell lines. We found that the efficiency of EJ varies among cancer cells; however, there was no remarkable difference in the mechanism and expression of EJ proteins. Interestingly, cancer cells with lower levels of EJ possessed elevated expression of BCL2 and vice versa. Removal of BCL2 by immunoprecipitation or protein fractionation led to elevated EJ. More importantly, we show that overexpression of BCL2 or the addition of purified BCL2 led to the down-regulation of EJ. Further, we found that BCL2 interacts with KU proteins both in vitro and in vivo. Hence, our results suggest that EJ in cancer cells could be negatively regulated by the anti-apoptotic protein, BCL2, and this may contribute toward increased chromosomal abnormalities in cancer.

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Centred space vector PWM (CSVPWM) technique is popularly used for three level voltage source inverters. The reference voltage vector is synthesized by time-averaging of the three nearest voltage vectors produced by the inverter. Identifying the three voltage vectors, and calculation of the dwelling time for each vector are both computationally intensive. This paper analyses the process of PWM generation in CSVPWM. This analysis breaks up a three-level inverter into six different conceptual two level inverters in different regions of the fundamental cycle. Control of 3-level inverter is viewed as the control of the appropriate 2-level inverter. The analysis leads to a systematic simplification of the computations involved, finally resulting in a computationally efficient PWM algorithm. This algorithm exploits the equivalence between triangle comparison and space vector approaches to PWM generation. This algorithm does not involve any 3-phase/2-phase or 2-phase/3-phase transformation. This also does not involve any transformation from rectangular to polar coordinates, and vice versa. Further no evaluation of trigonometric functions is necessary. This algorithm also provides for the mitigation of DC neutral point unbalance, and is well suited to digital implementation. Simulation and experimental results are presented.

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Reorganizing a dataset so that its hidden structure can be observed is useful in any data analysis task. For example, detecting a regularity in a dataset helps us to interpret the data, compress the data, and explain the processes behind the data. We study datasets that come in the form of binary matrices (tables with 0s and 1s). Our goal is to develop automatic methods that bring out certain patterns by permuting the rows and columns. We concentrate on the following patterns in binary matrices: consecutive-ones (C1P), simultaneous consecutive-ones (SC1P), nestedness, k-nestedness, and bandedness. These patterns reflect specific types of interplay and variation between the rows and columns, such as continuity and hierarchies. Furthermore, their combinatorial properties are interlinked, which helps us to develop the theory of binary matrices and efficient algorithms. Indeed, we can detect all these patterns in a binary matrix efficiently, that is, in polynomial time in the size of the matrix. Since real-world datasets often contain noise and errors, we rarely witness perfect patterns. Therefore we also need to assess how far an input matrix is from a pattern: we count the number of flips (from 0s to 1s or vice versa) needed to bring out the perfect pattern in the matrix. Unfortunately, for most patterns it is an NP-complete problem to find the minimum distance to a matrix that has the perfect pattern, which means that the existence of a polynomial-time algorithm is unlikely. To find patterns in datasets with noise, we need methods that are noise-tolerant and work in practical time with large datasets. The theory of binary matrices gives rise to robust heuristics that have good performance with synthetic data and discover easily interpretable structures in real-world datasets: dialectical variation in the spoken Finnish language, division of European locations by the hierarchies found in mammal occurrences, and co-occuring groups in network data. In addition to determining the distance from a dataset to a pattern, we need to determine whether the pattern is significant or a mere occurrence of a random chance. To this end, we use significance testing: we deem a dataset significant if it appears exceptional when compared to datasets generated from a certain null hypothesis. After detecting a significant pattern in a dataset, it is up to domain experts to interpret the results in the terms of the application.

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Presently Bluetooth(BT) is one of the widely used device for personal communication. As BT devices are operating in the unlicensed ISM band, they are often subjected to the interference from WLAN. The band width of BT (1MHz) is narrower compare to the bandwidth of WLAN (22MHz). So for coexistence purpose it is important to observe the performance of narrow band signal BT in presence of wideband interference WLAN and vice versa. As there are many work on the performance of WLAN in presence BT interference 3]4]5]6], the main focus in this paper is on performance of BT in presence of WLAN interference in AWGN, Rayleigh fading channel. Then comparison of the performance using interference avoidance technique like adaptive frequency hopping, power control for BT system is given. Finally a conclusion is drawn observing the simulation results on the technique which is more suitable for WLAN interference mitigation in BT system.