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101.
102.
An adaptive noise cancellation scheme based on two-stage adaptive filtering as proposed by Van Compernolle [Proceedings of the IEEE International Conference on Acoustics, Speech and Signal Processing (IEEE, New York, 1990)] was tested for two identical directional microphones mounted in an endfire configuration within a single behind-the-ear (BTE) hearing aid. Speech intelligibility tests were carried out with two normal hearing subjects and three hearing aid users with moderate hearing losses, in a realistic test environment using open set words and sentences. A significant improvement, on average more than 5 dB, of speech reception threshold (SRT) in background noise was obtained.  相似文献   
103.
In order to analyze the efficiency of interphase FISH for the detection and monitoring of Ph+ cells in chronic myelogenous leukemia (CML) under interferon (IFN) treatment, the following experiments were performed: (1) 98 specimens derived from 32 patients were analyzed in parallel by dual-color FISH and by conventional chromosome analysis (CCA). A 300/200 kb BCR/ABL probe was used in all tests and a smaller 35.5/39 kb probe was tested in parallel in 22 BM samples; (2) 30 BM samples were prepared by direct harvest and by 24-h culture and were analyzed in parallel; (3) PB and BM samples obtained simultaneously from 11 patients were analyzed. The cut-off point for the recognition of BCR/ABL fusion was set at 2.4%, calculated as the mean percent of false positivity in 11 controls plus 3 s.d. A very close correlation was observed (r=0.994, r2=0.988, P < 0.0001) between the percentages of Ph+ cells as assessed by CCA and by interphase FISH in 98 samples (26 at diagnosis). There was a moderate overestimation of the frequency of Ph+ cells by FISH with respect to CCA, that was more evident at low-to-medium values of Ph positivity. Seven specimens without Ph+ metaphases (17-50 cells analyzed) were shown to carry 2.5-8% interphase cells with BCR/ABL fusion. Similar percentages of BCR/ABL+ nuclei were recorded in 22 samples hybridized using the 300/200 kb and the 35.5/39 kb probe-sets (variation range: 0-5%, mean 2.3%). A very good correlation between the frequency of Ph+ interphase cells was observed when analyzing in parallel BM preparations after direct harvest and after 24-h culture. Underestimation of the percentage of BCR/ABL+ cells was noted to occur in 2/11 PB samples, compared to BM samples, the remaining nine cases showing superimposable results at either sites. We arrived at the following conclusions: (1) dual-color FISH enables an accurate detection and monitoring of the size of the Ph-positive clone in CML at diagnosis and after IFN-therapy; (2) FISH is more accurate than CCA, especially at low levels of Ph-positive cells; (3) testing of directly harvested BM samples is feasible and accurate, giving the opportunity to perform centralized FISH analysis in the context of multicentre trials; (4) the percentage of BCR/ABL+ PB cells usually, though not invariably, reflects the frequency of mutated cells in the BM.  相似文献   
104.
From a study of 10 cases of our own and 13 cases of the literature, anomalies of chromosome 1q and 10q emerge as consistently occurring changes in an important subgroup of phyllodes tumors of the breast. Anomalies of chromosome 1 were the most frequent ones, with a gain of 1q material, and histologically the tumors in which these anomalies were found were low grade malignancies. Structural changes of 10q emerged as the second most frequent chromosome change.  相似文献   
105.
In the international literature on today’s urban condition, Flanders is presented as prime example of urban sprawl, generally described as unplanned incremental development induced by the quantum leap of private car ownership. The research on rural-urban landscapes in south-west Flanders qualifies and substantiates this assertion by analysing pre-war keystone processes of infrastructure planning in relation to land-use patterns and landscape transformations. The research reveals that not only the development of rural-urban landscapes reaches back far beyond the welfare state, fuelled by railways prior to highways, but also shows that the supposedly chaotic hybrid landscape has its roots in drawn-out landscape ideologies inscribed in public works policy. The analysis—which crosses the divides between disciplines (landscape and infrastructure planning), concepts (rural-urban, modern-traditional), and geographical scales (national, regional, local)—reveals consistently planned mechanisms of public works policy and landscape change underlying both the diffuse regional urbanisation patterns and local landscape transformations, which are generally perceived as spontaneous or vernacular developments. Infrastructure planning facilitated a spatial organisation that attributed centrality to the transport network rather than the metropolis, and that conceived a resilient infrastructure framework rather than a stylistic spatial constellation in order to steer and geographically root heterogeneous modernisation processes within the landscape.  相似文献   
106.

Introduction

The primary aim of the present study was to evaluate the short- and longer-term effects of a cycle training on children's cycling skills. A second aim of the study was to examine the effects of a cycle training, with and without parental involvement, on levels of cycling to school and on parental attitudes towards cycling.

Methods

Three participating schools were randomly assigned to the “intervention” (25 children), the “intervention plus parent” (34 children) or “control” condition (35 children). A cycle training (four sessions of 45 min) took place only in the intervention schools. Parents in the “intervention plus parent” condition were asked to assist their child in completing weekly homework tasks. Children's cycling skills were assessed, using a practical cycling test. All participating children also received a short parental questionnaire on cycling behavior and parental attitudes towards cycling. Assessments took place at baseline, within 1 week after the last session and at 5-months follow-up. Repeated measure analyses were conducted to evaluate the effects of the cycle training.

Results

Children's total cycling skill score increased significantly more from pre to post and from pre to 5-months follow-up in the intervention group than in the control group. On walking with the bicycle (F = 1.6), cycling in a straight line (F = 2.6), cycling a slalom (F = 1.9), cycling over obstacles (F = 2.1), cycling on a sloping surface (F = 1.7) and dismounting the bicycle (F = 2.0), the cycle training had no effect. For all other cycling skills, significant improvements were observed on short- and longer-term. No significant intervention effects were found on children's cycling to school levels (F = 1.9) and parental attitudes towards cycling.

Conclusion

The cycle training course was effective in improving children's cycling skills and the improvements were maintained 5 months later. However, the cycle training course was not effective in increasing children's cycling to school levels.  相似文献   
107.
Iterated local search for the team orienteering problem with time windows   总被引:1,自引:0,他引:1  
A personalised electronic tourist guide assists tourists in planning and enjoying their trip. The planning problem that needs to be solved, in real-time, can be modelled as a team orienteering problem with time windows (TOPTW). In the TOPTW, a set of locations is given, each with a score, a service time and a time window. The goal is to maximise the sum of the collected scores by a fixed number of routes. The routes allow to visit locations at the right time and they are limited in length. The main contribution of this paper is a simple, fast and effective iterated local search meta-heuristic to solve the TOPTW. An insert step is combined with a shake step to escape from local optima. The specific shake step implementation and the fast evaluation of possible improvements, produces a heuristic that performs very well on a large and diverse set of instances. The average gap between the obtained results and the best-known solutions is only 1.8% and the average computation time is decreased with a factor of several hundreds. For 31 instances, new best solutions are computed.  相似文献   
108.
A newly developed assay for IgA class antibody to hepatitis E virus (IgA anti-HEV) was used to study 145 serum samples collected during an outbreak of an enterically transmitted hepatitis that occurred in 3 villages in the lower Shebeli region of Southern Somalia between January, 1988 and November, 1989. A total of 52.4% of the afflicted patients were found positive for IgA anti-HEV, and 73.1% of these were also positive for IgM. Both antibodies disappeared during the convalescence period. Similar results were also seen in serum obtained from sporadic cases of acute waterborne hepatitis in Pakistan.  相似文献   
109.
A weighted nonlinear least squares method to solve the 8- or 16-term calibration problem for a 2-port vector network analyzer is given. The method handles the connection repeatability problem, provides a test to verify whether the calibration problem can be solved with the available data and generates “soft” bounds on the accuracy of the calibration. The computational issues to obtain a fast and accurate implementation are stressed  相似文献   
110.
Most of the translocations affecting the chromosome band 11q23, frequently seen in human acute leukemias, involve a restricted area of the HRX gene. We have characterized two t(1;11)(p32;q11) translocations which fuse the HRX gene to a novel gene, AF-1p on chromosome 1p32, in two myeloid leukemias. The der (11) chromosome expresses the 1368 N-terminal amino acids of HRX, including the AT-hook, snRNP and methyltransferase similarities, fused to almost all the AF-1p product. The predicted wild type AF-1p product is a 98 kDa acidic protein which does not exhibit similarity to the AF-4, AF-9 and ENL gene products. It is highly similar to the murine eps 15 gene product, which encodes a cytoplasmic phosphoprotein. Our data indicate that AF-1p defines another class of genes fused to HRX in 11q23 abnormalities.  相似文献   
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