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11.
Patients diagnosed with nodules (NO = 40) in a large university hospital clinic and an age-stratum matched nondiseased group (ND = 200) described adverse outcomes of vocal impairment on work and work-related communications. NOs were significantly more likely than NDs to report symptoms of hoarseness (73% vs. 26%), high-note difficulty (70% vs. 20%), difficulty speaking with a lower voice (53% vs. 13%) and a tired voice (50% vs. 10%), and their greatest source of physical discomfort was associated with scratchiness (61% vs. 3%). The average number of symptoms was four in NOs and less than one in NDs. Nodule patients were most concerned about the effects their voice problem would have on their future career (78% vs. 24%) and 49% of NOS reported their voice problem had an adverse work effect in the past compared with 4% of NDs. Having a voice condition limited current job performance in 39% of the NO group but only in 2% of the ND group. The results suggest that a diagnosis of nodules plays a major role in disrupting careers and work activities and that available educational programs and additional research are needed for improving their functional ability and preventing adverse outcomes in the lives of individuals with voice disorders. 相似文献
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Gibb AR Suckling DM Morris BD Dawson TE Bunn B Comeskey D Dymock JJ 《Journal of chemical ecology》2006,32(1):221-237
Pheromone gland extracts of the Australian guava moth Coscinoptycha improbana (Lepidoptera: Carposinidae), contained four compounds that elicited responses from male moth antennae in gas chromatography-electroantennogram
detection (GC-EAD) analyses. These were identified by GC-mass spectrometry as (Z)-7-tricosene (Z7-23Hy), (Z)-7-octadecen-11-one (Z7-11-one-18Hy), (Z)-7-nonadecen-11-one (Z7-11-one-19Hy), and (Z)-7-tricosen-11-one (Z7-11-one-23Hy) at a ratio of 65:23.5:1.5:10, respectively. Z7-23Hy, Z7-11-one-18Hy, and Z7-11-one-23Hy have not previously been reported as lepidopteran sex pheromone components. Z7-11-one-18Hy was active as a single component, and was synergized by Z7-11-one-23Hy but not Z7-11-one-19Hy, although the latter compound was weakly attractive as a single component. Addition of Z7-23Hy further increased attraction. The amount of the major pheromone component, Z7-11-one-18Hy in female pheromone gland extracts was estimated to be 16.4 ng/female (N = 8). Phenological data gathered over a 12-mo period in 2002 and 2003 using the binary blend indicated that moths are active
throughout the year. The pheromone has already been employed to monitor the spread of C. improbana in New Zealand and detect its presence in Queensland, Australia. 相似文献
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AbstractRecently, a literature has emerged using empirical techniques to study the evolution of international cities over many centuries; however, few studies examine long-run change within cities. Conventional models and concepts are not always appropriate and data issues make long-run neighbourhood analysis particularly problematic. This paper addresses some of these points. First, it discusses why the analysis of long-run urban change is important for modern urban policy and considers the most important concepts. Second, it constructs a novel data set at the micro level, which allows consistent comparisons of London neighbourhoods in 1881 and 2001. Third, the paper models some of the key factors that affected long-run change, including the role of housing. There is evidence that the relative social positions of local urban areas persist over time but, nevertheless, at fine spatial scales, local areas still exhibit change, arising from aggregate population dynamics, from advances in technology, and also from the effects of shocks, such as wars. In general, where small areas are considered, long-run changes are likely to be greater, because individuals are more mobile over short than long distances. Finally, the paper considers the implications for policy. 相似文献
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Alistair G. F. Gibb 《Construction Management & Economics》2013,31(3):307-315
Standardization and pre-assembly (S&P) are not new, but their application and their drivers, pragmatism and perception, need to be considered in the light of current technology and management practice. There are lessons to be learned from a historical review, but there are also numerous myths that must be dispelled: houses are not cars; maximum standardization is not always the answer; and, S&P do not have to cost more. Steven Groák worked with the author on the research project ‘Adding value to construction projects through standardisation and pre-assembly’ funded by CIRIA (Construction Industry Research and Information Association). The CIRIA project, which forms the basis of this paper, aimed to produce a review of the subject and guidance for clients and project teams through a comprehensive literature review, expert work5 shops and case study research. The paper defines S&P, discusses past, present and future applications (providing case study evidence) and presents the key benefits and implications of the optimized use of standardization and pre-assembly. 相似文献
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Goodwin A.R. Davies I.G.A. Gibb R.M. Murphy R.H. 《Lightwave Technology, Journal of》1988,6(9):1424-1434
Long-haul trunk telecommunication systems, particularly optical submarine cable systems, have especially demanding reliability requirements. The authors describe how the InGaAsP inverted-rib waveguide (IRW) laser was designed for use as the source for such single-mode systems by minimizing known degradation hazards. The results of an extensive reliability assurance program are summarized. This included wafer validation endurance tests, overstress tests, and package design and life tests. The results of 7 million life-test hours confirm that the IRW laser has extremely good reliability performance 相似文献
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A 20 year old male patient presented with recurrent panuveitis associated with painful buccal and genital ulcers, subcutaneous nodules and pustules (dermatographia) on the trunk, and positive pathergy (skin hypersensitivity to needle pricks) test. Laboratory examinations were nonrevealing except for a minimal rise in ESR. This patient meets the criteria set by James and Spiteri for Be?hets' Disease. This disease and its prognosis is discussed. Early recognition and treatment of this blinding and potentially fatal disorder is emphasised. 相似文献
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The properties of central ATP-mediated synaptic currents were studied using whole-cell patch-clamp recording in rat medial habenula slices. Release was shown to be calcium dependent with a Hill coefficient of approximately 2. The voltage dependence of synaptic current amplitudes was approximately linear. Some reduction of the synaptic current amplitudes was observed at 10 mM extracellular calcium, suggesting calcium block/permeability of the channels. This was confirmed by observation of current-voltage reversal potentials in different calcium concentrations. We estimate that the channels underlying half the synapses showed a negligible calcium permeability. In the other four out of eight synapses the results suggest a very high calcium permeability with an estimated PCa/PCs of > 10. Thus, at -70 mV, in 1 mM calcium, more than 15% of the ATP-mediated synaptic current is estimated to be carried by calcium, but only at synapses with calcium-permeable channels. Net current through these synaptic channels is also controlled by the voltage dependence of synaptic current decay time constants (increasing e-fold for 158 mV depolarization) and by a strong dependence of transmitter release on the frequency of stimulation of the presynaptic neurone, with failure rates increasing 3-fold as stimulation rates were increased from 1 to 10 Hz. 相似文献