950 resultados para false memories


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Designing an ultrahigh density linear superlattice array consisting of periodic blocks of different semiconductors in the strong confinement regime via a direct synthetic route remains an unachieved challenge in nanotechnology. We report a general synthesis route for the formulation of a large-area ultrahigh density superlattice array that involves adjoining multiple units of ZnS rods by prolate US particles at the tips. A single one-dimensional wire is 300-500 nm long and consists of periodic quantum wells with a barrier width of 5 nm provided by ZnS and a well width of 1-2 nm provided by CdS, defining a superlattice structure. The synthesis route allows for tailoring of ultranarrow laserlike emissions (fwhm approximate to 125 meV) originating from strong interwell energy dispersion along with control of the width, pitch, and registry of the superlattice assembly. Such an exceptional high-density superlattice array could form the basis of ultrahigh density memories in addition to offering opportunities for technological advancement in conventional heterojunction-based device applications.

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Acute knee injury is a common event throughout life, and it is usually the result of a traffic accident, simple fall, or twisting injury. Over 90% of patients with acute knee injury undergo radiography. An overlooked fracture or delayed diagnosis can lead to poor patient outcome. The major aim of this thesis was retrospectively to study imaging of knee injury with a special focus on tibial plateau fractures in patients referred to a level-one trauma center. Multi-detector computed tomography (MDCT) findings of acute knee trauma were studied and compared to radiography, as well as whether non-contrast MDCT can detect cruciate ligaments with reasonable accuracy. The prevalence, type, and location of meniscal injuries in magnetic resonance imaging (MRI) were evaluated, particularly in order to assess the prevalence of unstable meniscal tears in acute knee trauma with tibial plateau fractures. The possibility to analyze with conventional MRI the signal appearance of menisci repaired with bioabsorbable arrows was also studied. The postoperative use of MDCT was studied in surgically treated tibial plateau fractures: to establish the frequency and indications of MDCT and to assess the common findings and their clinical impact in a level-one trauma hospital. This thesis focused on MDCT and MRI of knee injuries, and radiographs were analyzed when applica-ble. Radiography constitutes the basis for imaging acute knee injury, but MDCT can yield information beyond the capabilities of radiography. Especially in severely injured patients , sufficient radiographs are often difficult to obtain, and in those patients, radiography is unreliable to rule out fractures. MDCT detected intact cruciate ligaments with good specificity, accuracy, and negative predictive value, but the assessment of torn ligaments was unreliable. A total of 36% (14/39) patients with tibial plateau fracture had an unstable meniscal tear in MRI. When a meniscal tear is properly detected preoperatively, treatment can be combined with primary fracture fixation, thus avoiding another operation. The number of meniscal contusions was high. Awareness of the imaging features of this meniscal abnormality can help radiologists increase specificity by avoiding false-positive findings in meniscal tears. Postoperative menisci treated with bioabsorbable arrows showed no difference, among different signal intensities in MRI, among menisci between patients with operated or intact ACL. The highest incidence of menisci with an increased signal intensity extending to the meniscal surface was in patients whose surgery was within the previous 18 months. The results may indicate that a rather long time is necessary for menisci to heal completely after arrow repair. Whether the menisci with an increased signal intensity extending to the meniscal surface represent improper healing or re-tear, or whether this is just the earlier healing feature in the natural process remains unclear, and further prospective studies are needed to clarify this. Postoperative use of MDCT in tibial plateau fractures was rather infrequent even in this large trauma center, but when performed, it revealed clinically significant information, thus benefitting patients in regard to treatment.

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The significance of treating rainfall as a chaotic system instead of a stochastic system for a better understanding of the underlying dynamics has been taken up by various studies recently. However, an important limitation of all these approaches is the dependence on a single method for identifying the chaotic nature and the parameters involved. Many of these approaches aim at only analyzing the chaotic nature and not its prediction. In the present study, an attempt is made to identify chaos using various techniques and prediction is also done by generating ensembles in order to quantify the uncertainty involved. Daily rainfall data of three regions with contrasting characteristics (mainly in the spatial area covered), Malaprabha, Mahanadi and All-India for the period 1955-2000 are used for the study. Auto-correlation and mutual information methods are used to determine the delay time for the phase space reconstruction. Optimum embedding dimension is determined using correlation dimension, false nearest neighbour algorithm and also nonlinear prediction methods. The low embedding dimensions obtained from these methods indicate the existence of low dimensional chaos in the three rainfall series. Correlation dimension method is done on th phase randomized and first derivative of the data series to check whether the saturation of the dimension is due to the inherent linear correlation structure or due to low dimensional dynamics. Positive Lyapunov exponents obtained prove the exponential divergence of the trajectories and hence the unpredictability. Surrogate data test is also done to further confirm the nonlinear structure of the rainfall series. A range of plausible parameters is used for generating an ensemble of predictions of rainfall for each year separately for the period 1996-2000 using the data till the preceding year. For analyzing the sensitiveness to initial conditions, predictions are done from two different months in a year viz., from the beginning of January and June. The reasonably good predictions obtained indicate the efficiency of the nonlinear prediction method for predicting the rainfall series. Also, the rank probability skill score and the rank histograms show that the ensembles generated are reliable with a good spread and skill. A comparison of results of the three regions indicates that although they are chaotic in nature, the spatial averaging over a large area can increase the dimension and improve the predictability, thus destroying the chaotic nature. (C) 2010 Elsevier Ltd. All rights reserved.

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The motivation behind the fusion of Intrusion Detection Systems was the realization that with the increasing traffic and increasing complexity of attacks, none of the present day stand-alone Intrusion Detection Systems can meet the high demand for a very high detection rate and an extremely low false positive rate. Multi-sensor fusion can be used to meet these requirements by a refinement of the combined response of different Intrusion Detection Systems. In this paper, we show the design technique of sensor fusion to best utilize the useful response from multiple sensors by an appropriate adjustment of the fusion threshold. The threshold is generally chosen according to the past experiences or by an expert system. In this paper, we show that the choice of the threshold bounds according to the Chebyshev inequality principle performs better. This approach also helps to solve the problem of scalability and has the advantage of failsafe capability. This paper theoretically models the fusion of Intrusion Detection Systems for the purpose of proving the improvement in performance, supplemented with the empirical evaluation. The combination of complementary sensors is shown to detect more attacks than the individual components. Since the individual sensors chosen detect sufficiently different attacks, their result can be merged for improved performance. The combination is done in different ways like (i) taking all the alarms from each system and avoiding duplications, (ii) taking alarms from each system by fixing threshold bounds, and (iii) rule-based fusion with a priori knowledge of the individual sensor performance. A number of evaluation metrics are used, and the results indicate that there is an overall enhancement in the performance of the combined detector using sensor fusion incorporating the threshold bounds and significantly better performance using simple rule-based fusion.

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Aging in a country village This dissertation examines what kind of environment of aging a small country village is, who elderly villagers are and what kind of everyday life they have. The qualitative material gathered through ethnographic field work at a village situated in Southern Finland consists of a field work diary and 34 interviews of elderly villagers. The dissertation is based on social gerontology and village research. The key concepts are: the environment of aging; locality and local identity; and way of life. The village is examined as a social and physical environment of aging. Difficulties regarding mobility are the biggest challenges for elderly villagers in their everyday life. The social environment of aging is constructed by historical, cultural and local factors. The village community is formed by many small sub-communities. An elderly villager s status in a village community and her/his social competence affect the formation of her/his social network and the quality of her/his environment of aging. The dissertation examines the local identities of older villagers and their relationships to the village. The local identities can be based on the village, memories or on many places, or a place and places may not be of great importance for a person s identity. The local identity of an older villager affects her/his experiences of living in the village and her/his future plans to move away from the village. The everyday life of an older villager is constructed by rhythms, routines and repetitions. However, there are differences between how everyday lives are arranged among elderly villagers, which are explained by the concept of a way of life. Four ways of life were found. Nature and its importance are a background to all four ways of life. A traditional way of life is based on continuity and hard work, a family-oriented way of life on family members and relatives. A mobile way of life is characterized by symbolic and concrete mobility. An original way of life is marked by independent loneliness . In practice, a person s way of life is always constructed by two or many ways of life.

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In this study, which pertains to the field of social gerontology and family research, I analyse the meaning of everyday life as perceived by elderly couples living at home. I use the ethnographic approach, with the aim of interpreting meanings from the elderly people s personal point of view and to increase understanding of their way of life. The study deepens our conception of what gives purpose to the everyday life of elderly people. The number of elderly couples is growing and, to an increasing extent, a couple will live and cope together to a ripe old age. Such coping can also be viewed as an important resource for society. Ethnography tries to get close to people's life practices. I examine the day-to-day life of elderly couples based on textual data, which I obtained by visiting the homes of 16 couples in a total of five small municipalities in Southern Finland. The couples had married soon after the war or in the early 1950s. I found that the aspiration towards continuity, which unites the concepts of place and home, housework and a long marriage, is the most important notion connecting the discussion themes. The results show that in the opinion of the elderly, the concept of a good life is intertwined with a long marriage spent at home, as well as its values. Old people find that they lead an independent life if they feel that they can hold on to the key features of their way of life. Elderly couples ability to cope with everyday life involves taking care of housework and other tasks around the home together. This means that they support one another and have common goals and aspirations. Daily tasks provide substance in the lives of elderly couples. Each day has its rhythm, and the pace of this rhythm is set by routine and habits. Satisfaction stems from the fact that you can do something you are good at. The couples have also revised the division of housework. Men have learned to perform new tasks around the house when their wives can no longer manage them by themselves. Some tasks are given up. Day-to-day life at home and around the house provides room for men s participation. Mutual support and care between husband and wife can also protect them from having to resort to outside or official help. Old couples integrate their life experiences and memories, as well as present and future risks and opportunities. They wish to carry on their lives as before, and still think that their present life corresponds with their idea of a good life. Key words: elderly couples, continuity theory of aging, everyday life, social gerontology, family research

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This ethnographic study investigates encounters between volunteers and older people at the Kerava Municipal Health Centre inpatient ward for chronic care. Volunteer activities have been under development, in cooperation with the Voluntary Work Center (Talkoorengas), since the start of the 1990s. When my research began in 2003, nine of the volunteers came to the ward on set days per week or visited the ward according to their own timetables. The volunteers ranged in age from 54 to 78 years. With one exception, all of them were on pension. Nearly all of them had been volunteers for more than ten years. My study is research on ageing, the focal point being older people, whether volunteers or those receiving assistance. The research questions are: How is volunteer work implemented in daily routines at the ward? How is interaction created in encounters between the older people and the volunteers? What meanings does volunteer work create for the older people and the volunteers? The core material of my research is observation material, which is supplemented by interviews, documentation and photographs. The materials have been analysed by using theme analysis and ethnomethodological discussion analysis. In the presentation of the research findings, I have structured the materials into three main chapters: space and time; hands and touch; and words and tones. The chapter on space and time examines time and space paths, privacy and publicness, and celebrations as part of daily life. The volunteers open and create social arenas for the older people through chatting and singing together, celebrations in the dayroom or poetry readings at the bedside. The supporting theme of the chapter on hands and touch is bodily closeness in care and the associated concrete physical presence. The chapter highlights the importance of everyday routines, such as meals and rituals, as elements that bring security. Stimuli in daily life, such as handicrafts in groups, pass time but also give older people the experience of meaningful activity and bring back positive memories of their own life. The chapter on words and tones focuses on the social interaction and identity. The volunteers’ identity is built up into the identity of a helper and caregiver. The older people’s identity is built up into a care recipient’s identity, which in different situations is shaped into, among others, the identity of one who listens, remembers, does not remember, defends, composes poetry or is dying. The cornerstones of voluntary social care are participation, activity, trust and presence. Successful volunteer work calls for mutual trust between the older people, volunteers and the health care personnel, and for clear agreements on questions of responsibility, the status of volunteers and their role alongside professional personnel. This study indicates that volunteer work is a meaningful resource in work with older people.

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The purpose of this work is to use the concepts of human time and cultural trauma in a biographical study of the turning points in the recent history of Estonia. This research is primarily based on 148 in-depth biographical interviews conducted in Estonia and Sweden in 1995-2005, supplemented by excerpts from 5 collections and 10 individually published autobiographies. The main body of the thesis consists of six published and of two forthcoming separate refereed articles, summarised in the theoretical introduction, and Appendix of the full texts of three particular life stories. The topic of the first article is the generational composition and the collective action frames of anti-Soviet social mobilisation in Estonia in 1940-1990. The second article details the differentiation of the rites of passage and the calendar traditions as a strategy to adapt to the rapidly changed political realities, comparatively in Soviet Estonia and among the boat-refugees in Sweden. The third article investigates the life stories of the double-minded strategic generation of the Estonian-inclined Communists, who attempted to work within the Soviet system while professing to uphold the ideals of pre-war Estonia. The fourth article is concentrated on the problems of double mental standards as a coping strategy in a contradictory social reality. The fifth article implements the theory of cultural trauma for the social practice of singing nationalism in Estonia. The sixth article bridges the ideas of Russian theoreticians concerning cultural dialogue and the Western paradigm of cultural trauma, with examples from Estonian Russian life stories. The seventh article takes a biographical look at the logic of the unraveling of cultural trauma through four Soviet decades. The eighth article explores the re-shaping of citizen activities as a strategy of coping with the loss of the independent nation state, comparatively in Soviet Estonia and among Swedish Estonians. Cultural trauma is interpreted as the re-ordering of the society s value-normative constellation due to sharp, violent, usually political events. The first one under consideration was caused by the occupations of the Republic of Estonia by the Soviet army in 1940-45. After half a century of suppression the memories of these events resurfaced as different stories describing the long-term, often inter-generational strategies of coping with the value collapse. The second cultural trauma is revealed together with the collapse of the Soviet power and ideology in Estonia in 1991. According to empirical data, the following three trauma discourses have been reconstructed: - the forced adaptation to Soviet order of the homeland Estonians; - the difficulty of preserving Estonian identity in exile (Sweden); - the identity crisis of the Russian population of Estonia. Comparative analyses of these discourses have shown that opposing experiences and worldviews cause conflicting interpretations of the past. Different social and ethnic groups consider coping with cultural trauma as a matter of self-defence and create appropriate usable pasts to identify with. Keywords: human time, cultural trauma, frame analysis, discourse, life stories

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- Background Sonography is an important diagnostic tool in children with suspected appendicitis. Reported accuracy and appendiceal visualisation rates vary significantly, as does the management of equivocal ultrasound findings. The aim of this study was to audit appendiceal sonography at a tertiary children's hospital, and provide baseline data for a future prospective study. - Summary of work Records of children who underwent ultrasound studies for possible appendicitis between January 2008 and December 2010 were reviewed. Variables included patient demographics, sonographic appendix characteristics, and secondary signs. Descriptive statistics and analysis using ANOVA, Mann-Whitney U test, and ROC curves were performed. Mater Human Research Ethic Committee approval was granted. - Summary of results There were 457 eligible children. Using a dichotomous diagnostic model (including equivocal results), sensitivity was 89.6%, specificity 91.6%, and diagnostic yield of 40.7%. ROC curve analysis of a 6mm diameter cut-off was 0.88 AUC (95% CI 0.80 to 0.95). - Discussion and conclusions Sonography is an accurate test for acute appendicitis in children, with a high sensitivity and negative predictive value. A diameter of 6mm as an absolute cut-off in a binary model can lead to false findings. Results were compared with available literature. Recent publications propose categorising diameter1 and integrating secondary signs2 to improve accuracy and provide more meaningful results to clinicians. This study will be a benchmark for future studies with multiple diagnostic categorisation.

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Conflict, Unity, Oblivion: Commemoration of the Liberation War by the Civic Guard and the Veterans´ Union in 1918-1944 The Finnish Civil War ended in May 1918 as a victory for the white side. The war was named by the winners as the Liberation War and its legacy became a central theme for public commemorations during the interwar period. At the same time the experiences of the defeated were hindered from becoming a part of the official history of Finland. The commemoration of the war was related not only to the war experience but also to a national mission, which was seen fulfilled with the independence of Finland. Although the idea of the commemoration was to form a unifying non-political scene for the nation, the remembrance of the Liberation War rather continued than sought to reconcile to the conflict of 1918. The outbreak of the war between the Soviet Union and Finland in 1939 immediately affected the memory culture. The new myth of the Miracle of the Winter War, which referred to the unity shown by the people, required a marginalization of controversial memory of the Liberation War. This study examines from the concepts of public memory and narrative templates how the problematic experience of a civil war developed to a popular public commemoration. Instead of dealing with the manipulative and elite-centered grandiose commemoration projects, the study focuses on the more modest local level and emphasizes the significance of local memory agents and narrative templates of collective memory. The main subjects in the study are the Civil Guard and the Veterans´ Union. Essential for the widespread movement was the development of the Civic Guard from a wartime organization to a peacetime popular movement. The guards, who identified themselves trough the memories and the threats of civil war, formed a huge network of memory agents in every corner of the country. They effectively linked both local memory with official memory and the civic society with the state level. Only with the emergence of the right wing veteran movement in the 30ies did the tensions grow between the two levels of public memory. The study shows the diversity of the commemoration movement of the Liberation War. It was not only a result of a nation-state project and political propaganda, but also a way for local communities to identify and strengthen themselves in a time of political upheaval and uncertainty.

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Abstract: Research on translation universals has its roots in the need to make generalizations about the features that distinguish translations from non-translations. They go back to the old tradition of negative comments about the failings of typical translations. These comments concern the relations between translations and the target language, and between translations and their source texts. With the rise of descriptive studies, and the use of corpus research methods borrowed from linguistics, the search for the typical features of translations became more systematic. A number of hypotheses about potential universals have been proposed, and tested on different languages and language pairs. Some of them are evidently false; on others, the jury is still out. If some hypotheses continue to be supported by empirical evidence, the question then arises of how they might best be explained. There has been fierce criticism of some of the assumptions underlying the search for universals, including the use of the term 'universal'itself, but the approach has also brought clear methodological benefits.

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Spike detection in neural recordings is the initial step in the creation of brain machine interfaces. The Teager energy operator (TEO) treats a spike as an increase in the `local' energy and detects this increase. The performance of TEO in detecting action potential spikes suffers due to its sensitivity to the frequency of spikes in the presence of noise which is present in microelectrode array (MEA) recordings. The multiresolution TEO (mTEO) method overcomes this shortcoming of the TEO by tuning the parameter k to an optimal value m so as to match to frequency of the spike. In this paper, we present an algorithm for the mTEO using the multiresolution structure of wavelets along with inbuilt lowpass filtering of the subband signals. The algorithm is efficient and can be implemented for real-time processing of neural signals for spike detection. The performance of the algorithm is tested on a simulated neural signal with 10 spike templates obtained from [14]. The background noise is modeled as a colored Gaussian random process. Using the noise standard deviation and autocorrelation functions obtained from recorded data, background noise was simulated by an autoregressive (AR(5)) filter. The simulations show a spike detection accuracy of 90%and above with less than 5% false positives at an SNR of 2.35 dB as compared to 80% accuracy and 10% false positives reported [6] on simulated neural signals.

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The move towards IT outsourcing is the first step towards an environment where compute infrastructure is treated as a service. In utility computing this IT service has to honor Service Level Agreements (SLA) in order to meet the desired Quality of Service (QoS) guarantees. Such an environment requires reliable services in order to maximize the utilization of the resources and to decrease the Total Cost of Ownership (TCO). Such reliability cannot come at the cost of resource duplication, since it increases the TCO of the data center and hence the cost per compute unit. We, in this paper, look into aspects of projecting impact of hardware failures on the SLAs and techniques required to take proactive recovery steps in case of a predicted failure. By maintaining health vectors of all hardware and system resources, we predict the failure probability of resources based on observed hardware errors/failure events, at runtime. This inturn influences an availability aware middleware to take proactive action (even before the application is affected in case the system and the application have low recoverability). The proposed framework has been prototyped on a system running HP-UX. Our offline analysis of the prediction system on hardware error logs indicate no more than 10% false positives. This work to the best of our knowledge is the first of its kind to perform an end-to-end analysis of the impact of a hardware fault on application SLAs, in a live system.

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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.