921 resultados para SENSORINEURAL HEARING LOSS


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One of the most important functions in the individual development is the interaction and integration of each sensory input. There exist two competing theories, i.e. the deficiency theory and the compensatory theory, regarding the origin and nature of changes in visual functions observed after auditory deprivation. The deficiency theory proposed that integrative processes are essential for normal development. In contrast, the compensatory theory stated that the loss of one sense may be met by a greater reliance upon, therefore an enhancement of the remaining senses. Given that hearing impaired children’s learning depends primarily on visual information, it is important to recognize the differences of visual attention between them and their hearing age-mates. Differences among age groups could exist in either selectivity or sustained attention. Study 1 and study 2 explored the selective and sustained attention development of hearing impaired and hearing students with average cognitive ability, aged from 7 years to college students. The analysis and discussion of the results are based on the visual attention development as well as deficiency theory and compensatory theory. According to the results of the study 1 and study 2, the spatial distribution and controlling of the visual attention between hearing impaired and hearing students were also investigated in the study 3 and study 4. The present work showed that: Firstly, both hearing impaired and hearing participants had the similar developmental trajectory of the sustained attention. The ability of children’s sustained attention appeared to improve with age, and in adolescence it reached the peak. The hearing impaired participants had the comparable sustained attention skills to the matched hearing ones. Besides, the results of the hearing impaired participants showed that they could maintain their attention and vigilance on the current task over the observation period. Secondly, group differences of visual attention development were found between hearing impaired and hearing participants. In the childhood, the visual attention developmental speed of the hearing impaired children was slower than that of the hearing ones. The selective attention skill of the hearing impaired were not comparable to the hearing ones, however, their selective skill improved with age, so in the adulthood, hearing impaired students showed the slight advantage in the selective attention skill over the hearing ones. Thirdly, hearing impaired and hearing participants showed the similar spatial distribution in the attention resources. In the low perceptual load condition, both participants were suffered great interference of the distrator at the fixation. In contrast, in the high perceptual load condition, hearing impaired adults were suffered more interference of the peripheral distractor, which suggested that they distributed more attention resources to the peripheral field when faced difficult tasks. Fourthly, both groups showed similar processing in the visual attention tasks. That is, they both searched the target with only the color feature in a parallel way, but in a serial way while processing orientation feature and the features with the combination of the color and orientation. Furthermore, the results indicated that two groups show similar ways in the attention controlling. In summary, the present study showed that visual attention development was dependent upon the integration of multimodal sensory information. Because of the interaction and integration of the input from various sensory, it has a negative impact on the intact sensory at the early stage of one sensory loss, however, it can better the functions of other intact sensory gradually with development and practice.

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Chemical and biological processes, such as dissolution in gypsiferous sands and biodegradation in waste refuse, result in mass or particle loss, which in turn lead to changes in solid and void phase volumes and grading. Data on phase volume and grading changes have been obtained from oedometric dissolution tests on sand–salt mixtures. Phase volume changes are defined by a (dissolution-induced) void volume change parameter (Λ). Grading changes are interpreted using grading entropy coordinates, which allow a grading curve to be depicted as a single data point and changes in grading as a vector quantity rather than a family of distribution curves. By combining Λ contours with pre- to post-dissolution grading entropy coordinate paths, an innovative interpretation of the volumetric consequences of particle loss is obtained. Paths associated with small soluble particles, the loss of which triggers relatively little settlement but large increase in void ratio, track parallel to the Λ contours. Paths associated with the loss of larger particles, which can destabilise the sand skeleton, tend to track across the Λ contours.

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Islamic financing instruments can be categorised into profit and loss/risk sharing and non-participatory instruments. Although profit and loss sharing instruments such as musharakah are widely accepted as the ideal form of Islamic financing, prior studies suggest that alternative instruments such as murabahah are preferred by Islamic banks. Nevertheless, prior studies did not explore factors that influence the use of Islamic financing among non-financial firms. Our study fills this gap and contributes new knowledge in several ways. First, we find no evidence of widespread use of Islamic financing instruments across non-financial firms. This is because the instruments are mostly used by less profitable firms with higher leverage (i.e., risky firms). Second, we find that profit and loss sharing instruments are hardly used, whilst the use of murabahah is dominant. Consistent with the prediction of moral-hazard-risk avoidance theory, further analysis suggests that users with a lower asset base (to serve as collateral) are associated with murabahah financing. Third, we present a critical discourse on the contentious nature of murabahah as practised. The economic significance and ethical issues associated with murabahah as practised should trigger serious efforts to steer Islamic corporate financing towards risk-sharing more than the controversial rent-seeking practice.

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Natural herbs have been in use for weight loss purposes since history began. However, the current global obesity epidemic and the rise in obesity-related chronic diseases, including type-II diabetes and cancer, have highlighted the need for novel and effective approaches for herbal remedies. Whilst the popularity of several prescribed and non-prescribed slimming aids and herbal plant supplements have been marketed for their weight loss efficacy, single and multi-ingredient herbal supplements are still being investigated for their single or combined weight loss benefits. Limited research have highlighted an interesting efficacy for several popular herbal plant supplements including caffeine and capsaicin, Ayurvedic preparations and herbal teas, resulting in various degrees of effectiveness including thermogenic, appetite control and psychological benefits such as mood state. Recent research has suggested acute augmented weight-loss effects of combining herbal ingestion with exercise. For example, ingesting green tea, yerba mate and/or caffeine have been shown to increase metabolic rate, and augmented fatty acid metabolism and to increase energy expenditure from fatty acid sources during exercise with various intensities, particularly at low and moderate intensities. Other promising weight-loss effects have also been also reported for combining exercise with multi-ingredient herbal supplements, particularly those that are rich in phytochemicals and caffeoyl derivatives. Combining herbal ingestions with exercise still require further research in order to establish the supplementation most effective protocols in terms of dosage and timing, and to determine the long-term benefits, particularly those related to exercise protocols, and the long term adherence to sustain the weight loss outcomes.

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People with sight loss in the United Kingdom are known to have lower levels of emotional wellbeing and to be at higher risk of depression. Consequently ‘having someone to talk to’ is an important priority for people with visual impairment. An on-line survey of the provision of emotional support and counselling for people affected by sight loss across the UK was undertaken. The survey was distributed widely and received 182 responses. There were more services offering ‘emotional support’, in the form of listening and information and advice giving, than offered ‘counselling’. Services were delivered by providers with differing qualifications in a variety of formats. Waiting times were fairly short and clients presented with a wide range of issues. Funding came from a range of sources, but many felt their funding was vulnerable. Conclusions have been drawn about the need for a national standardised framework for the provision of emotional support and counselling services for blind and partially sighted people in the UK

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For a given TCP flow, exogenous losses are those occurring on links other than the flow's bottleneck link. Exogenous losses are typically viewed as introducing undesirable "noise" into TCP's feedback control loop, leading to inefficient network utilization and potentially severe global unfairness. This has prompted much research on mechanisms for hiding such losses from end-points. In this paper, we show through analysis and simulations that low levels of exogenous losses are surprisingly beneficial in that they improve stability and convergence, without sacrificing efficiency. Based on this, we argue that exogenous loss awareness should be taken into account in any AQM design that aims to achieve global fairness. To that end, we propose an exogenous-loss aware Queue Management (XQM) that actively accounts for and leverages exogenous losses. We use an equation based approach to derive the quiescent loss rate for a connection based on the connection's profile and its global fair share. In contrast to other queue management techniques, XQM ensures that a connection sees its quiescent loss rate, not only by complementing already existing exogenous losses, but also by actively hiding exogenous losses, if necessary, to achieve global fairness. We establish the advantages of exogenous-loss awareness using extensive simulations in which, we contrast the performance of XQM to that of a host of traditional exogenous-loss unaware AQM techniques.

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One of TCP's critical tasks is to determine which packets are lost in the network, as a basis for control actions (flow control and packet retransmission). Modern TCP implementations use two mechanisms: timeout, and fast retransmit. Detection via timeout is necessarily a time-consuming operation; fast retransmit, while much quicker, is only effective for a small fraction of packet losses. In this paper we consider the problem of packet loss detection in TCP more generally. We concentrate on the fact that TCP's control actions are necessarily triggered by inference of packet loss, rather than conclusive knowledge. This suggests that one might analyze TCP's packet loss detection in a standard inferencing framework based on probability of detection and probability of false alarm. This paper makes two contributions to that end: First, we study an example of more general packet loss inference, namely optimal Bayesian packet loss detection based on round trip time. We show that for long-lived flows, it is frequently possible to achieve high detection probability and low false alarm probability based on measured round trip time. Second, we construct an analytic performance model that incorporates general packet loss inference into TCP. We show that for realistic detection and false alarm probabilities (as are achievable via our Bayesian detector) and for moderate packet loss rates, the use of more general packet loss inference in TCP can improve throughput by as much as 25%.

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End-to-End differentiation between wireless and congestion loss can equip TCP control so it operates effectively in a hybrid wired/wireless environment. Our approach integrates two techniques: packet loss pairs (PLP) and Hidden Markov Modeling (HMM). A packet loss pair is formed by two back-to-back packets, where one packet is lost while the second packet is successfully received. The purpose is for the second packet to carry the state of the network path, namely the round trip time (RTT), at the time the other packet is lost. Under realistic conditions, PLP provides strong differentiation between congestion and wireless type of loss based on distinguishable RTT distributions. An HMM is then trained so observed RTTs can be mapped to model states that represent either congestion loss or wireless loss. Extensive simulations confirm the accuracy of our HMM-based technique in classifying the cause of a packet loss. We also show the superiority of our technique over the Vegas predictor, which was recently found to perform best and which exemplifies other existing loss labeling techniques.

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The current congestion-oriented design of TCP hinders its ability to perform well in hybrid wireless/wired networks. We propose a new improvement on TCP NewReno (NewReno-FF) using a new loss labeling technique to discriminate wireless from congestion losses. The proposed technique is based on the estimation of average and variance of the round trip time using a filter cal led Flip Flop filter that is augmented with history information. We show the comparative performance of TCP NewReno, NewReno-FF, and TCP Westwood through extensive simulations. We study the fundamental gains and limits using TCP NewReno with varying Loss Labeling accuracy (NewReno-LL) as a benchmark. Lastly our investigation opens up important research directions. First, there is a need for a finer grained classification of losses (even within congestion and wireless losses) for TCP in heterogeneous networks. Second, it is essential to develop an appropriate control strategy for recovery after the correct classification of a packet loss.

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A secure sketch (defined by Dodis et al.) is an algorithm that on an input w produces an output s such that w can be reconstructed given its noisy version w' and s. Security is defined in terms of two parameters m and m˜ : if w comes from a distribution of entropy m, then a secure sketch guarantees that the distribution of w conditioned on s has entropy m˜ , where λ = m−m˜ is called the entropy loss. In this note we show that the entropy loss of any secure sketch (or, more generally, any randomized algorithm) on any distribution is no more than it is on the uniform distribution.

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Current Internet transport protocols make end-to-end measurements and maintain per-connection state to regulate the use of shared network resources. When a number of such connections share a common endpoint, that endpoint has the opportunity to correlate these end-to-end measurements to better diagnose and control the use of shared resources. A valuable characterization of such shared resources is the "loss topology". From the perspective of a server with concurrent connections to multiple clients, the loss topology is a logical tree rooted at the server in which edges represent lossy paths between a pair of internal network nodes. We develop an end-to-end unicast packet probing technique and an associated analytical framework to: (1) infer loss topologies, (2) identify loss rates of links in an existing loss topology, and (3) augment a topology to incorporate the arrival of a new connection. Correct, efficient inference of loss topology information enables new techniques for aggregate congestion control, QoS admission control, connection scheduling and mirror site selection. Our extensive simulation results demonstrate that our approach is robust in terms of its accuracy and convergence over a wide range of network conditions.

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This report details the findings of research undertaken with family carers in Cork during 2007 – 2008. The research was undertaken to elicit the views and experiences of family carers, and in so doing, to gain insight into their perspectives on family caring and on associated support mechanisms. It is hoped that, thereafter, policy can draw on these observations. Three key themes emerged from the research itself. These are (i) the role and position of the family carer in society, (ii) the process of family caring itself and (iii) access to and knowledge of key support services. This report, then, draws attention to the extent and dynamics of family caring, as seen through the opinions and experiences of carers located in and nearby Cork city. It has the following format. In the first instance we turn our attention to a discussion of family caring in Ireland, and associated supports more generally. This includes a discussion on key issues arising in the general discourse around family caring in Ireland and internationally, in order to provide a context from which to locate the experiences of carers involved in this research study. Thereafter, we detail the methodology employed in this research study, which followed a method of research enquiry that values the input of participants from the early stages of research focus and design, and which incorporates qualitative and quantitative methods of enquiry. The research was conceptualised and developed in conjunction with The Carers Association, Cork in keeping with an approach to social research that attempts to link academic and activist/advocacy interests. Its aims were to identify issues that family carers in the locality considered important, with a view to contributing to local knowledge, providing a forum for ongoing research, and to informing policy developments on carers. The focus of the report then turns to profiling carers who participated in the research, examining the care they provide, and discussing support they receive from family, friends and neighbours – from informal sources. We then look to the access carers have to formal and public, community-based support services. We examine their experiences of, and concerns with regard to some of these key services, and look at ways that such issues might be addressed. The next section concentrates on financial supports, a range of which are available to carers, for instance, to supplement income and to assist with home renovations. We look at their uptake and issues arising, again with a view to understanding and addressing them from the perspectives of the service users. Finally, the report turns its attention to aspirations that carers have for themselves; in terms of their own personal, training, and employment options. The report concludes by drawing attention to key issues discussed throughout and makes a number of key recommendations, aimed at addressing the voiced opinions and experiences of carers that have emerged through the research.

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This report provides an update to research conducted in 2008 on the experiences and access to supports available to family carers in Cork and published as Hearing Family Carers (O’Riordan, O’hAdhmaill and Duggan 2010). It includes additional research carried out in 2013 with some of the original participants who partook in the earlier research. Given the more recent changes in supports in the context of austerity measures it was considered necessary to consult carers again with reference to their more current experiences, supports and the challenges they face in their informal caring roles.

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AIMS: To assess the impact of involuntary job loss due to plant closure or layoff on relapse to smoking and smoking intensity among older workers. DESIGN, PARTICIPANTS, SAMPLE: Data come from the Health and Retirement Study, a nationally representative survey of older Americans aged 51-61 in 1991 followed every 2 years beginning in 1992. The 3052 participants who were working at the initial wave and had any history of smoking comprise the main sample. METHODS: Primary outcomes are smoking relapse at wave 2 (1994) among baseline former smokers, and smoking quantity at wave 2 among baseline current smokers. As reported at the wave 2 follow-up, 6.8% of the sample experienced an involuntary job loss between waves 1 and 2. FINDINGS: Older workers have over two times greater odds of relapse subsequent to involuntary job loss than those who did not. Further, those who were current smokers prior to displacement that did not obtain new employment were found to be smoking more cigarettes, on average, post-job loss. CONCLUSIONS: The stress of job loss, along with other significant changes associated with leaving one's job, which would tend to increase cigarette consumption, must outweigh the financial hardship which would tend to reduce consumption. This highlights job loss as an important health risk factor for older smokers.