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Polymer-DNA conjugates in which one nucleic acid strand contains fluorine-substituted nucleobases have been prepared and characterised. The efficacy of these novel F-19 nucleic acid-polymer conjugates as sensitive and selective in vitro reporters of DNA binding events is demonstrated through a number of rapid-acquisition MR sequences. The conjugates respond readily and in a sequence specific manner to external target oligonucleotide sequences by changes in hybridisation. In turn, these structural changes in polymer-nucleotide conjugates translate into responses which are detectable in fluorine relaxation and diffusion switches, and which can be monitored by in vitro Spin Echo and DOSY NMR spectroscopy. Although complementary to conventional FRET methods, the excellent diagnostic properties of fluorine nuclei make this approach a versatile and sensitive probe of molecular structure and conformation in polymeric assemblies.

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Measurable electrical signal is generated when a gas flows over a variety of solids, including doped semiconductors, even at the modest speed of a few meters per second. The underlying mechanism is an interesting interplay of Bernoulli's principle and the Seebeck effect. The electrical signal depends on the square of Mach number (M) and is proportional to the Seebeck coefficient (S) of the solids. Here we present experimental estimate of the response time of the signal rise and fall process, i.e. how fast the semiconductor materials respond to a steady flow as soon as it is set on or off. A theoretical model is also presented to understand the process and the dependence of the response time on the nature and physical dimensions of the semiconductor material used and they are compared with the experimental observations. (c) 2007 Elsevier B.V. All rights reserved.

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It is known that by employing space-time-frequency codes (STFCs) to frequency selective MIMO-OFDM systems, all the three diversity viz spatial, temporal and multipath can be exploited. There exists space-time-frequency block codes (STFBCs) designed using orthogonal designs with constellation precoder to get full diversity (Z.Liu, Y.Xin and G.Giannakis IEEE Trans. Signal Processing, Oct. 2002). Since orthogonal designs of rate one exists only for two transmit antennas, for more than two transmit antennas STFBCs of rate-one and full-diversity cannot be constructed using orthogonal designs. This paper presents a STFBC scheme of rate one for four transmit antennas designed using quasi-orthogonal designs along with co-ordinate interleaved orthogonal designs (Zafar Ali Khan and B. Sundar Rajan Proc: ISIT 2002). Conditions on the signal sets that give full-diversity are identified. Simulation results are presented to show the superiority of our codes over the existing ones.

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The problem of constructing space-time (ST) block codes over a fixed, desired signal constellation is considered. In this situation, there is a tradeoff between the transmission rate as measured in constellation symbols per channel use and the transmit diversity gain achieved by the code. The transmit diversity is a measure of the rate of polynomial decay of pairwise error probability of the code with increase in the signal-to-noise ratio (SNR). In the setting of a quasi-static channel model, let n(t) denote the number of transmit antennas and T the block interval. For any n(t) <= T, a unified construction of (n(t) x T) ST codes is provided here, for a class of signal constellations that includes the familiar pulse-amplitude (PAM), quadrature-amplitude (QAM), and 2(K)-ary phase-shift-keying (PSK) modulations as special cases. The construction is optimal as measured by the rate-diversity tradeoff and can achieve any given integer point on the rate-diversity tradeoff curve. An estimate of the coding gain realized is given. Other results presented here include i) an extension of the optimal unified construction to the multiple fading block case, ii) a version of the optimal unified construction in which the underlying binary block codes are replaced by trellis codes, iii) the providing of a linear dispersion form for the underlying binary block codes, iv) a Gray-mapped version of the unified construction, and v) a generalization of construction of the S-ary case corresponding to constellations of size S-K. Items ii) and iii) are aimed at simplifying the decoding of this class of ST codes.

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In this paper, we present an analysis for the bit error rate (BER) performance of space-time block codes (STBC) from generalized complex orthogonal designs for M-PSK modulation. In STBCs from complex orthogonal designs (COD), the norms of the column vectors are the same (e.g., Alamouti code). However, in generalized COD (GCOD), the norms of the column vectors may not necessarily be the same (e.g., the rate-3/5 and rate-7/11 codes by Su and Xia in [1]). STBCs from GCOD are of interest because of the high rates that they can achieve (in [2], it has been shown that the maximum achievable rate for STBCs from GCOD is bounded by 4/5). While the BER performance of STBCs: from COD (e.g., Alamouti code) can be simply obtained from existing analytical expressions for receive diversity with the same diversity order by appropriately scaling the SNR, this can not be done for STBCs from GCOD (because of the unequal norms of the column vectors). Our contribution in this paper is that we derive analytical expressions for the BER performance of any STBC from GCOD. Our BER analysis for the GCOD captures the performance of STBCs from COD as special cases. We validate our results with two STBCs from GCOD reported by Su and Xia in [1], for 5 and 6 transmit antennas (G(5) and G(6) in [1]) with rates 7/11 and 3/5, respectively.

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This paper addresses the problem of detecting and resolving conflicts due to timing constraints imposed by features in real-time and hybrid systems. We consider systems composed of a base system with multiple features or controllers, each of which independently advise the system on how to react to input events so as to conform to their individual specifications. We propose a methodology for developing such systems in a modular manner based on the notion of conflict-tolerant features that are designed to continue offering advice even when their advice has been overridden in the past. We give a simple priority-based scheme forcomposing such features. This guarantees the maximal use of each feature. We provide a formal framework for specifying such features, and a compositional technique for verifying systems developed in this framework.

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This thesis studies quantile residuals and uses different methodologies to develop test statistics that are applicable in evaluating linear and nonlinear time series models based on continuous distributions. Models based on mixtures of distributions are of special interest because it turns out that for those models traditional residuals, often referred to as Pearson's residuals, are not appropriate. As such models have become more and more popular in practice, especially with financial time series data there is a need for reliable diagnostic tools that can be used to evaluate them. The aim of the thesis is to show how such diagnostic tools can be obtained and used in model evaluation. The quantile residuals considered here are defined in such a way that, when the model is correctly specified and its parameters are consistently estimated, they are approximately independent with standard normal distribution. All the tests derived in the thesis are pure significance type tests and are theoretically sound in that they properly take the uncertainty caused by parameter estimation into account. -- In Chapter 2 a general framework based on the likelihood function and smooth functions of univariate quantile residuals is derived that can be used to obtain misspecification tests for various purposes. Three easy-to-use tests aimed at detecting non-normality, autocorrelation, and conditional heteroscedasticity in quantile residuals are formulated. It also turns out that these tests can be interpreted as Lagrange Multiplier or score tests so that they are asymptotically optimal against local alternatives. Chapter 3 extends the concept of quantile residuals to multivariate models. The framework of Chapter 2 is generalized and tests aimed at detecting non-normality, serial correlation, and conditional heteroscedasticity in multivariate quantile residuals are derived based on it. Score test interpretations are obtained for the serial correlation and conditional heteroscedasticity tests and in a rather restricted special case for the normality test. In Chapter 4 the tests are constructed using the empirical distribution function of quantile residuals. So-called Khmaladze s martingale transformation is applied in order to eliminate the uncertainty caused by parameter estimation. Various test statistics are considered so that critical bounds for histogram type plots as well as Quantile-Quantile and Probability-Probability type plots of quantile residuals are obtained. Chapters 2, 3, and 4 contain simulations and empirical examples which illustrate the finite sample size and power properties of the derived tests and also how the tests and related graphical tools based on residuals are applied in practice.

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The goal of this study was to examine the role of organizational causal attribution in understanding the relation of work stressors (work-role overload, excessive role responsibility, and unpleasant physical environment) and personal resources (social support and cognitive coping) to such organizational-attitudinal outcomes as work engagement, turnover intention, and organizational identification. In some analyses, cognitive coping was also treated as an organizational outcome. Causal attribution was conceptualized in terms of four dimensions: internality-externality, attributing the cause of one’s successes and failures to oneself, as opposed to external factors, stability (thinking that the cause of one’s successes and failures is stable over time), globality (perceiving the cause to be operative on many areas of one’s life), and controllability (believing that one can control the causes of one’s successes and failures). Several hypotheses were derived from Karasek’s (1989) Job Demands–Control (JD-C) model and from the Job Demands–Resources (JD-R) model (Demerouti, Bakker, Nachreiner & Schaufeli, 2001). Based on the JD-C model, a number of moderation effects were predicted, stating that the strength of the association of work stressors with the outcome variables (e.g. turnover intentions) varies as a function of the causal attribution; for example, unpleasant work environment is more strongly associated with turnover intention among those with an external locus of causality than among those with an internal locuse of causality. From the JD-R model, a number of hypotheses on the mediation model were derived. They were based on two processes posited by the model: an energy-draining process in which work stressors along with a mediating effect of causal attribution for failures deplete the nurses’ energy, leading to turnover intention, and a motivational process in which personal resources along with a mediating effect of causal attribution for successes foster the nurses’ engagement in their work, leading to higher organizational identification and to decreased intention to leave the nursing job. For instance, it was expected that the relationship between work stressors and turnover intention could be explained (mediated) by a tendency to attribute one’s work failures to stable causes. The data were collected from among Finnish hospital nurses using e-questionnaires. Overall 934 nurses responded the questionnaires. Work stressors and personal resources were measured by five scales derived from the Occupational Stress Inventory-Revised (Osipow, 1998). Causal attribution was measured using the Occupational Attributional Style Questionnaire (Furnham, 2004). Work engagement was assessed through the Utrecht Work Engagement Scale (Schaufeli & al., 2002), turnover intention by the Van Veldhoven & Meijman (1994) scale, and organizational identification by the Mael & Ashforth (1992) measure. The results provided support for the function of causal attribution in the overall work stress process. Findings related to the moderation model can be divided into three main findings. First, external locus of causality along with job level moderated the relationship between work overload and cognitive coping. Hence, this interaction was evidenced only among nurses in non-supervisory positions. Second, external locus of causality and job level together moderated the relationship between physical environment and turnover intention. An opposite pattern of interaction was found for this interaction: among nurses, externality exacerbated the effect of perceived unpleasantness of the physical environment on turnover intention, whereas among supervisors internality produced the same effect. Third, job level also disclosed a moderation effect for controllability attribution over the relationship between physical environment and cognitive coping. Findings related to the mediation model for the energetic process indicated that the partial model in which work stressors have also a direct effect on turnover intention fitted the data better. In the mediation model for the motivational process, an intermediate mediation effect in which the effects of personal resources on turnover intention went through two mediators (e.g., causal dimensions and organizational identification) fitted the data better. All dimensions of causal attribution appeared to follow a somewhat unique pattern of mediation effect not only for energetic but also for motivational processes. Overall findings on mediation models partly supported the two simultaneous underlying processes proposed by the JD-R model. While in the energetic process the dimension of externality mediated the relationship between stressors and turnover partially, all the dimensions of causal attribution appeared to entail significant mediator effects in the motivational process. The general findings supported the moderation effect and the mediation effect of causal attribution in the work stress process. The study contributes to several research traditions, including the interaction approach, the JD-C, and the JD-R models. However, many potential functions of organizational causal attribution are yet to be evaluated by relevant academic and organizational research. Keywords: organizational causal attribution, optimistic / pessimistic attributional style, work stressors, organisational stress process, stressors in nursing profession, hospital nursing, JD-R model, personal resources, turnover intention, work engagement, organizational identification.

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Discursive Matrixes of Motherhood examines women's discourse on their experiences of new motherhood in Finland and France. It sets out from two culturally prevalent turns of speech observed in different social forums: in conversations amongst mothers with tertiary education and in the print media. The pool of data includes: 30 interviews, 8 autobiographically inspired novels and 80 items from women's magazines. With instruments loaned from the toolbox of rhetorical analysis, the recurrence of certain expressions or clichés is analyzed with regard to the national, cultural, biographical, political and daily contexts and settings in which the speaking subjects are immersed. "Staying at home is such a short and special time", the first expression under scrutiny, caught the sociological eye because of its salience in Finland and because it appeared as contradictory with a core characteristic of the Finnish context:long family leave. The cliché was found to function as a discursive micromechanism which swept mothers' 'complaints' under the proverbial carpet. Proper emotions and decency in mother-talk thereby appear as collective achievements. An opposite phenomenon - that of the scaling up of rewards procured by children - was also discerned in the data. Indeed, the French expression "Profiter de mon enfant" ["making the most of my child"/"enjoying my child"] is interpreted as a crystallization of a hedonist ethos of motherhood in everyday language. Secondly, the recurrence of this utterance is analyzed in the light of a requisite located in child-rearing expert literature: that of pleasure that women should take in mothering. Hence, one of the rules found to structure the discursive matrixes of motherhood is the laudability and audibility of enjoyment and conversely the discretion and discouragement of 'complaints'. The cultivation of decent matches between certain categories of emotions and certain categories of individuals also appears as a characteristic of discursive matrixes. One of the methodological findings relates to the fact that such matches may be constituted as sociological objects through the identification of recurrent discursive crystallizations in a given culture. Ideal matches may crystallize in turns of speech and mismatches can be managed through clichés. Becoming a mother entails an immersion in such a particular economy of speech. Key words: mothers, motherhood, transition to parenthood, family, emotions, morality, bonds, rhetorical analysis, discourse analysis, media analysis, France, Finland, comparative sociology

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In 2015, Victoria passed laws removing the time limit in which a survivor of child sexual abuse can commence a civil claim for personal injury. The law applies also to physical abuse, and to psychological injury arising from those forms of abuse. In 2016, New South Wales made almost identical legal reforms. These reforms were partly motivated by the recommendations of inquiries into institutional child abuse. Of particular relevance is that the Australian Royal Commission Into Institutional Responses to Child Sexual Abuse recommended in 2015 that all States and Territories remove their time limits for civil claims. This presentation explores the problems with standard time limits when applied to child sexual abuse cases (whether occurring within or beyond institutions), the scientific, ethical and legal justifications for lifting the time limits, and solutions for future law reform.

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The problem of scheduling divisible loads in distributed computing systems, in presence of processor release time is considered. The objective is to find the optimal sequence of load distribution and the optimal load fractions assigned to each processor in the system such that the processing time of the entire processing load is a minimum. This is a difficult combinatorial optimization problem and hence genetic algorithms approach is presented for its solution.

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Passive wavelength/time fiber-optic code division multiple access (WIT FO-CDMA) network is a viable option for highspeed access networks. Constructions of 2-D codes, suitable for incoherent WIT FO-CDMA, have been proposed to reduce the time spread of the 1-D sequences. The 2-D constructions can be broadly classified as 1) hybrid codes and 2) matrix codes. In our earlier work [141, we had proposed a new family of wavelength/time multiple-pulses-per-row (W/T MPR) matrix codes which have good cardinality, spectral efficiency and at the same time have the lowest off-peak autocorrelation and cross-correlation values equal to unity. In this paper we propose an architecture for a WIT MPR FO-CDAM network designed using the presently available devices and technology. A complete FO-CDMA network of ten users is simulated, for various number of simultaneous users and shown that 0 --> 1 errors can occur only when the number of interfering users is at least equal to the threshold value.

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This thesis studies binary time series models and their applications in empirical macroeconomics and finance. In addition to previously suggested models, new dynamic extensions are proposed to the static probit model commonly used in the previous literature. In particular, we are interested in probit models with an autoregressive model structure. In Chapter 2, the main objective is to compare the predictive performance of the static and dynamic probit models in forecasting the U.S. and German business cycle recession periods. Financial variables, such as interest rates and stock market returns, are used as predictive variables. The empirical results suggest that the recession periods are predictable and dynamic probit models, especially models with the autoregressive structure, outperform the static model. Chapter 3 proposes a Lagrange Multiplier (LM) test for the usefulness of the autoregressive structure of the probit model. The finite sample properties of the LM test are considered with simulation experiments. Results indicate that the two alternative LM test statistics have reasonable size and power in large samples. In small samples, a parametric bootstrap method is suggested to obtain approximately correct size. In Chapter 4, the predictive power of dynamic probit models in predicting the direction of stock market returns are examined. The novel idea is to use recession forecast (see Chapter 2) as a predictor of the stock return sign. The evidence suggests that the signs of the U.S. excess stock returns over the risk-free return are predictable both in and out of sample. The new "error correction" probit model yields the best forecasts and it also outperforms other predictive models, such as ARMAX models, in terms of statistical and economic goodness-of-fit measures. Chapter 5 generalizes the analysis of univariate models considered in Chapters 2 4 to the case of a bivariate model. A new bivariate autoregressive probit model is applied to predict the current state of the U.S. business cycle and growth rate cycle periods. Evidence of predictability of both cycle indicators is obtained and the bivariate model is found to outperform the univariate models in terms of predictive power.

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The research topic is the formation of nuclear family understanding and the politicization of nuclear family. Thus, the question is how did family historically become understood particularly as nuclear family and why did it become central in terms of politics and social? The research participates in discussions on the concept and phenomena of family. Central theme of analysis is to ask what is family? Family is seen as historically contingent and the discussions on the concept and phenomena are done via historical analysis. Center of attention is nuclear family, thus, a distinction between the concepts of family and nuclear family is made to be able to focus on historically specific phenomena of nuclear family. Family contrary to the concept of nuclear family -- in general is seen to be able to refer to families in all times and all cultures, as well as all types of families in our times and culture. The nuclear family understanding is examined through two separate themes, that of parent-child relationships and marital relations. Two simultaneous processes give nuclear family relations its current form: on the one hand the marital couple as the basis of family is eroding and losing its capacity to hold the family together; on the other, in Finland at least from 1950s on, the normal development of the child has became to be seen ontologically bound to the (biological) mother and (via her to) the father. In the nucleus of the family is the child: the biological, psychological and social processes of normal development are seen ontologically bound to the nuclear family relations. Thus, marriages can collapse, but nuclear family is unbreakable. What is interesting is the historical timing: as nuclear family relations had just been born, the marriage dived to a crisis. The concept and phenomena of nuclear family is analyzed in the context of social and politics (in Finnish these two collapses in the concept of yhteiskunnallinen , which refers both to a society as natural processes as well as to the state in terms of politics). Family is political and social in two senses. First, it is understood as the natural origin of the social and society. Human, by definition, is understood as a social being and the origin of social, in turn, is seen to be in the family. Family is seen as natural to species. Disturbances in family life lead to un-social behaviour. Second, family is also seen as a political actor of rights and obligations: family is obligated to control the life of its members. The state patronage is seen at the same time inevitable family life is way too precious to leave alone -- and problematic as it seems to disturb the natural processes of the family or to erode the autonomy of it. The rigueur of the nuclear family is in the role it seems to hold in the normal development of the child and the future of the society. The disturbances in the families first affect the child, then the society. In terms of possibility to re-think the family the natural and political collide: the nuclear family seems as natural, unchangeable, un- negotiable. Nuclear family is historically ontologised. The biological, psychological and social facts of family seem to be contrary to the idea of negotiation and politics the natural facts of family problematise the politics of family. The research material consists of administrational documents, memoranda, consultation documents, seminar reports, educational writings, guidebooks and newspaper articles in family politics between 1950s and 1990s.