886 resultados para Memory Awareness


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The mechanisms responsible for the generation and maintenance of immunological memory to Plasmodium are poorly understood and the reasons why protective immunity in humans is so difficult to achieve and rapidly lost remain a matter for debate. A possible explanation for the difficulty in building up an efficient immune response against this parasite is the massive T cell apoptosis resulting from exposure to high-dose parasite Ag. To determine the immunological mechanisms required for long-term protection against P. chabaudi malaria and the consequences of high and low acute phase parasite loads for acquisition of protective immunity, we performed a detailed analysis of T and B cell compartments over a period of 200 days following untreated and drug-treated infections in female C57BL/6 mice. By comparing several immunological parameters with the capacity to control a secondary parasite challenge, we concluded that loss of full protective immunity is not determined by acute phase parasite load nor by serum levels of specific IgG2a and IgG1. Abs, but appears to be a consequence of the progressive decline in memory T cell response to parasites, which occurs similarly in untreated and drug-treated mice with time after infection. Furthermore, by analyzing adoptive transfer experiments, we confirmed the major role of CD4(+) T cells for guaranteeing long-term full protection against P. chabaudi malaria. The Journal of Immunology, 2008, 181: 8344-8355.

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The human malaria parasite Plasmodium falciparum expresses erythrocyte-surface directed variant antigens which are important virulence factors Many are transcribed from multigene families and presumably their mode of expression is strictly controlled to guarantee immune evasion in the human host. In order to elucidate the dynamics of rif transcription and to investigate if rif switching is comparable to var switching we monitored rif variant gene expression in parasites with different cytoadhesive properties as well as after a number of reinvasions. We found identical transcripts in parasite lines with different adhesive phenotypes suggesting that rif genes do not have a critical role in determining the cytoadhesion specificity of infected erythrocytes. We show for the first time that rif genes may show a conserved mode of transcription, maintaining the previously dominant rif transcript in subsequent reinvasions, but also observed rapid switching at rates up to 45% per generation, much higher than for the var gene family. (C) 2009 Elsevier B.V. All rights reserved.

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A modified version of the social habituation/dis-habituation paradigm was employed to examine social recognition memory in Wistar rats during two opposing (active and inactive) circadian phases, using different intertrial intervals (30 and 60 min). Wheel-running activity was monitored continuously to identify circadian phase. To avoid possible masking effects of the light-dark cycle, the rats were synchronized to a skeleton photoperiod, which allowed testing during different circadian phases under identical lighting conditions. In each trial, an infantile intruder was introduced into an adult`s home-cage for a 5-minute interaction session, and social behaviors were registered. Rats were exposed to 5 trials per day for 4 consecutive days: oil days I and 2, each resident was exposed to the same intruder; on days 3 and 4, each resident was exposed to a different intruder in each trial. I he resident`s social investigatory behavior was more intense when different intruders were presented compared to repeated presentation of the same intruder, suggesting social recognition memory. This effect was stronger when the rats were tested during the inactive phase and when the intertrial interval was 60 min, These findings Suggest that social recognition memory, as evaluated in this modified habituation/dis-habituation paradigm, is influenced by the circadian rhythm phase during which testing is performed, and by intertrial interval. (C) 2008 Elsevier Inc. All rights reserved.

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Searching in a dataset for elements that are similar to a given query element is a core problem in applications that manage complex data, and has been aided by metric access methods (MAMs). A growing number of applications require indices that must be built faster and repeatedly, also providing faster response for similarity queries. The increase in the main memory capacity and its lowering costs also motivate using memory-based MAMs. In this paper. we propose the Onion-tree, a new and robust dynamic memory-based MAM that slices the metric space into disjoint subspaces to provide quick indexing of complex data. It introduces three major characteristics: (i) a partitioning method that controls the number of disjoint subspaces generated at each node; (ii) a replacement technique that can change the leaf node pivots in insertion operations; and (iii) range and k-NN extended query algorithms to support the new partitioning method, including a new visit order of the subspaces in k-NN queries. Performance tests with both real-world and synthetic datasets showed that the Onion-tree is very compact. Comparisons of the Onion-tree with the MM-tree and a memory-based version of the Slim-tree showed that the Onion-tree was always faster to build the index. The experiments also showed that the Onion-tree significantly improved range and k-NN query processing performance and was the most efficient MAM, followed by the MM-tree, which in turn outperformed the Slim-tree in almost all the tests. (C) 2010 Elsevier B.V. All rights reserved.

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In this paper, we consider a hyperbolic thermoelastic system of memory type in domains with moving boundary. The problem models vibrations of an elastic bar under thermal effects according to the heat conduction law of Gurtin and Pipkin. Global existence is proved by using the penalty method of Lions. (c) 2007 Elsevier Inc. All rights reserved.

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Augmented Lagrangian methods for large-scale optimization usually require efficient algorithms for minimization with box constraints. On the other hand, active-set box-constraint methods employ unconstrained optimization algorithms for minimization inside the faces of the box. Several approaches may be employed for computing internal search directions in the large-scale case. In this paper a minimal-memory quasi-Newton approach with secant preconditioners is proposed, taking into account the structure of Augmented Lagrangians that come from the popular Powell-Hestenes-Rockafellar scheme. A combined algorithm, that uses the quasi-Newton formula or a truncated-Newton procedure, depending on the presence of active constraints in the penalty-Lagrangian function, is also suggested. Numerical experiments using the Cute collection are presented.

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The presentation was offered as part of the CUNY Library Assessment Conference, Reinventing Libraries: Reinventing Assessment, held at the City University of New York in June 2014.

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This research paper has been prepared by Bachelor students from Dalarna University in Borlänge. The project is centered on a case study of ICA – Kvantum and its brand awareness among customers. The purpose of this study is to find out that which measures can help ICA-Kvantum to create brand awareness among its current and potential customers by looking in to the importance of information of its offerings and use of effective communication tools to convey this information. Further, to recommend them what they need to do, to increase brand awareness among their customers with the help of managerial implications. The research question was formulated as what actions could be seen effective for ICA-Kvantum to maintain or improve brand awareness among its current and potential customers.The project was created with the help of theoretical concepts of brand awareness, brand loyalty, perceived quality, consumer decision model, integrated marketing communication approach and strategic planning process. These theories were applied in this thesis in order to find out the most effective communication measures to maintain or improve brand awareness among current and potential customers of ICA-Kvantum.The primary and secondary data was collected. Primary data was gathered through the survey among ICA-Kvantum customers in the front of the store in Borlänge. The personal interview with manager was conducted in the office of ICA-Kvantum store located in Borlänge. Secondary data was gathered from textbooks, academic journals, theses and websites.The empirical findings have been presented in detail and then analyzed with the help of theoretical concepts. The analysis and further results from survey and interview focused on importance of information, marketing communication tools, brand awareness and loyalty, perceived quality and implementation of strategic planning process. Moreover, the main weaknesses and strengths of ICA-Kvantun have been evaluated. The conclusion including short summary of analysis and its results have been provided at the end. Each weakness of issues related to brand awareness i.e. importance of information, effectiveness of marketing communication tools and strengths and weaknesses of ICA-Kvantum discussed in the paper, has been pointed out along with solutions and managerial implications.

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BACKGROUND: Persons with Alzheimer's disease (AD) sometimes express themselves through behaviours that are difficult to manage for themselves and their caregivers, and to minimise these symptoms alternative methods are recommended. For some time now, animals have been introduced in different ways into the environment of persons with dementia. Animal-Assisted Therapy (AAT) includes prescribed therapy dogs visiting the person with dementia for a specific purpose. AIM: This study aims to illuminate the meaning of the lived experience of encounters with a therapy dog for persons with Alzheimer's disease. METHOD: Video recorded sessions were conducted for each visit of the dog and its handler to a person with AD (10 times/person). The observations have a life-world approach and were transcribed and analysed using a phenomenological hermeneutical approach. RESULTS: The result shows a main theme 'Being aware of one's past and present existence', meaning to connect with one's senses and memories and to reflect upon these with the dog. The time spent with the dog shows the person recounting memories and feelings, and enables an opportunity to reach the person on a cognitive level. CONCLUSIONS: The present study may contribute to health care research and provide knowledge about the use of trained therapy dogs in the care of older persons with AD in a way that might increase quality of life and well-being in persons with dementia. IMPLICATIONS FOR PRACTICE: The study might be useful for caregivers and dog handlers in the care of older persons with dementia.

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