972 resultados para marginal discrepancy


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Acanthoplacatus gen. nov., a new genus of viviparous gyrodactylid, is described from the rns and skin of siganid fishes from the Great Barrier Reef, Australia. The genus is characterized by a muscular, tube-like haptor with 16 marginal hooks on the posterior margin. The ventral lobe of the haptor is located anteriorly relative to the dorsal lobe and contains a pair of hamuli and a ventral bar with posteriorly-projecting ventral bar membrane. A dorsal bar is absent. Five pairs of posterior gland cells surround the posterior terminations of the gut. The male copulatory organ is a muscular, non-eversible bulb with several spines around the distal opening. Species of Acanthoplacatus have a bilateral excretory system consisting of six pairs of flame cells and a pair of excretory bladders. Seven new species are described: Acanthoplacatus adlardi sp. nov. and A. amplihamus sp. nov. from Siganus punctatus (Forster, 1801), A. brauni sp. nov. from S. corallinus (Valenciennes, 1835), A. parvihamus sp. nov. from S. vulpinus (Schlegel and Mueller, 1845), A. puelli sp. nov. from S. puellus Schlegel, 1852, A. shieldsi sp. nov. from S. lineatus (Valenciennes, 1835) and A. sigani sp. nov. from S. fuscescens (Houttuyn, 1782). Species can be discriminated by shape and size of the hamuli, marginal hooks and ventral bar and by male copulatory organ sclerite morphology. Three species (A. brauni sp. nov., A. shieldsi sp. nov. and A. sigani sp. nov.) were assessed for seasonal variation of sclerite size. Ten of thirteen morphological characters showed seasonal variation in size for at least one of the species. The characters were longer in winter except dorsal root tissue cap width. Only one character, marginal hook length, showed significant seasonal variation for all three species. Species of Acanthoplacatus were observed to attach using only the marginal hooks and the role of hamuli in attachment is unclear. The dorsal rn of the host is the preferred site for most species but the anal fin, caudal fin and body surfaces are preferred by some species. Prevalences for species range from 57 to 100%.

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1. Parasitoids are predicted to spend longer in patches with more hosts, but previous work on Cotesia rubecula (Marshall) has not upheld this prediction, Tests of theoretical predictions may be affected by the definition of patch leaving behaviour, which is often ambiguous. 2. In this study whole plants were considered as patches and assumed that wasps move within patches by means of walking or flying. Within-patch and between-patch flights were distinguished based on flight distance. The quality of this classification was tested statistically by examination of log-survivor curves of flight times. 3. Wasps remained longer in patches with higher host densities, which is consistent with predictions of the marginal value theorem (Charnov 1976). tinder the assumption that each flight indicates a patch departure, there is no relationship between host density and leaving tendency. 4. Oviposition influences the patch leaving behaviour of wasps in a count down fashion (Driessen et al. 1995), as predicted by an optimal foraging model (Tenhumberg, Keller & Possingham 2001). 5. Wasps spend significantly longer in the first patch encountered following release, resulting in an increased rate of superparasitism.

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A randomized controlled trial was carried out to measure the societal costs of realtime teledermatology compared with those of conventional hospital care in New Zealand. Two rural health centres were linked to a specialist hospital via ISDN at 128 kbit/s. Over 10 months, 203 patients were referred for a specialist dermatological consultation and 26 were followed up, giving a total of 229 consultations. Fifty-four per cent were randomized to the teledermatology consultation and 46% to the conventional hospital consultation. A cost-minimization analysis was used to calculate the total costs of both types of dermatological consultation. The total cost of the 123 teledermatology consultations was NZ$34,346 and the total cost of the 106 conventional hospital consultations was NZ$30,081. The average societal cost of the teledermatology consultation was therefore NZ$279.23 compared with NZ$283.79 for the conventional hospital consultation. The marginal cost of seeing an additional patient was NZ$135 via teledermatology and NZ$284 via conventional hospital appointment. From a societal viewpoint, and assuming an equal outcome, teledermatology was a more cost-efficient use of resources than conventional hospital care.

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A randomized controlled trial was carried out to measure the cost-effectiveness of realtime teledermatology compared with conventional outpatient dermatology care for patients from urban and rural areas. One urban and one rural health centre were linked to a regional hospital in Northern Ireland by ISDN at 128 kbit/s. Over two years, 274 patients required a hospital outpatient dermatology referral -126 patients (46%) were randomized to a telemedicine consultation and 148 (54%) to a conventional hospital outpatient consultation. Of those seen by telemedicine, 61% were registered with an urban practice, compared with 71% of those seen conventionally. The clinical outcomes of the two types of consultation were similar - almost half the patients were managed after a single consultation with the dermatologist. The observed marginal cost per patient of the initial realtime teledermatology consultation was f52.85 for those in urban areas and f59.93 per patient for those from rural areas. The observed marginal cost of the initial conventional consultation was f47.13 for urban patients and f48.77 for rural patients. The total observed costs of teledermatology were higher than the costs of conventional care in both urban and rural areas, mainly because of the fixed equipment costs. Sensitivity analysis using a real-world scenario showed that in urban areas the average costs of the telemedicine and conventional consultations were about equal, while in rural areas the average cost of the telemedicine consultation was less than that of the conventional consultation.

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With the exception of the sodium D-lines, recent calculations of line broadening cross sections for several multiplets of sodium by Leininger et al (Leininger T, Gadea F X and Dickinson A 2000 J. Phys. B: At. Mol. Opt. Phys. 33 1805) are in substantial disagreement with cross sections interpolated from the tables of Anstee and O'Mara (Anstee and O'Mara 1995 Mon. Not. R. Astron. Soc. 276 859) and Barklem and O'Mara (Barklem P S and O'Mara B J 1997 Mon. Not. R. Astron. Soc. 290 102). The discrepancy is as large as a factor of 3 for the 3p-4d multiplet. The two theories are tested by using the results of each to synthesize lines in the solar spectrum. It is found that generally the data from the theory of Anstee, Barklem and O'Mara produce the best match to the observed solar spectrum. It is found, using a simple model for reflection of the optical electron by the potential barrier between the two atoms, that the reflection coefficient is too large for avoided crossings with the upper states of subordinate lines to contribute to line broadening, supporting the neglect of avoided ionic crossings by Anstee, Barklem and O'Mara for these lines. The large discrepancies between the two sets of calculations is a result of an approximate treatment of avoided ionic crossings for these lines by Leininger et al (Leininger T, Gadea F X and Dickinson A 2000 J. Phys. B: At. Mol. Opt. Phys. 33 1805).

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During the Middle Jurassic, the regional environment of Curio Bay, southeast South Island, New Zealand, was a fluvial plain marginal to volcanic uplands. Intermittent flashy, poorly-confined flood events buried successive conifer forests. With the termination of each flood, soils developed and vegetation was reestablished. In most cases, this developed into coniferous forest. In approximately 40 m of vertical section, 10 fossil forest horizons can be distinguished, highlighting a type of fluvial architecture which is poorly documented. Flood-basin material is minimal, but a short-Lived floodbasin lake is inferred to have developed within the interval of study. Paleocurrent indicators suggest enclosure of the basin on more than one side. Sedimentation style suggests a relatively dry (less than humid but not arid) climate with seasonal rainfall. (C) 2001 Elsevier Science B.V. All rights reserved.

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This case study represents four years of audiological observations, testing and aural habilitation of a female child with a partial agenesis of the corpus callosum (ACC). The ACC was diagnosed by MRI scans to eliminate neurological causes for developmental delay at six months of age. This child was also born with a cleft palate and was diagnosed with Robinow Syndrome at 3 years and 3 months of age. The audiological results showed an improvement in hearing thresholds over the four-year period. The child’s opthamologist also reported an improvement in visual skills over time. The most interesting aspect of the child’s hearing was the discrepancy between the monaural and the binaural results. That is, when assessed binaurally she often presented with a mild to moderate mixed loss and when assessed monaurally she showed a moderate to severe mixed loss for the right ear and a severe mixed loss for the left ear. This discrepancy between binaural and monaural results was evident for both aided and unaided tests. Parental reports of the child’s hearing were consistent with the binaural clinical results. This case indicates the need for audiologists to: (a) carefully monitor the hearing of children with ACC, (b) obtain monaural and binaural hearing and aided thresholds results, and (c) compare these children’s functional abilities to the objective test results obtained. This case does question whether hearing aids are appropriate for children with ACC. If hearing aids are deemed to be appropriate, then hearing aids with compression characteristics should be considered.

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The specification of the erythroid lineage from hematopoietic stem cells requires the expression and activity of lineage-specific transcription factors. One transcription factor family that has several members involved in hematopoiesis is the Kruppel-like factor (KLF) family [1]. For example, erythroid KLF (EKLF) regulates beta -globin expression during erythroid differentiation [2-6]. KLFs share a highly conserved zinc finger-based DNA binding domain (DBD) that mediates binding to CACCC-box and GC-rich sites, both of which are frequently found in the promoters of hematopoietic genes. Here, we identified a novel Xenopus KLF gene, neptune, which is highly expressed in the ventral blood island (VBI), cranial ganglia, and hatching and cement glands. neptune expression is induced in response to components of the BMP-4 signaling pathway in injected animal cap explants. Similar to its family member, EKLF, Neptune can bind CACCC-box and GC-rich DNA elements. We show that Neptune cooperates with the hematopoietic transcription factor XGATA-1 to enhance globin induction in animal cap explants. A fusion protein comprised of Neptune's DBD and the Drosophila engrailed repressor domain suppresses the induction of globin in ventral marginal zones and in animal caps. These studies demonstrate that Neptune is a positive regulator of primitive erythropoiesis in Xenopus.

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A two-dimensional numerical simulation model of interface states in scanning capacitance microscopy (SCM) measurements of p-n junctions is presented-In the model, amphoteric interface states with two transition energies in the Si band gap are represented as fixed charges to account for their behavior in SCM measurements. The interface states are shown to cause a stretch-out-and a parallel shift of the capacitance-voltage characteristics in the depletion. and neutral regions of p-n junctions, respectively. This explains the discrepancy between - the SCM measurement and simulation near p-n junctions, and thus modeling interface states is crucial for SCM dopant profiling of p-n junctions. (C) 2002 American Institute of Physics.

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We extend the earlier model of condensate growth of Davis et at (Davis M J, Gardiner C W and Ballagh R J 2000 Phys. Rev. A 62 063608) to include the effect of gravity in a magnetic trap. We carry out calculations to model the experiment reported by Kohl et al (Kohl M, Davis M J, Gardiner C W, Hansch T and Esslinger T 2001 Preprint cond-mat/0106642) who study the formation of a rubidium Bose-Einstein condensate for a range of evaporative cooling parameters. We find that, in the regime where our model is valid, the theoretical curves agree with all the experimental data with no fitting parameters. However, for the slowest cooling of the gas the theoretical curve deviates significantly from the experimental curves. It is possible that this discrepancy may be related to the formation of a quasicondensate.

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This case study presents four and a half years of audiological observations, testing and aural habilitation of a female child with a partial agenesis of the corpus callosum (ACC). The ACC was diagnosed by MRI scan performed at 6 months of age to eliminate neurological causes for the developmental delay. This child was also born with a cleft palate and was diagnosed with Robinow Syndrome at 3 years and 3 months of age. The audiological results showed an improvement in hearing thresholds over the 4-year period. The child’s ophthalmologist also reported an improvement in visual skills over time. The most interesting aspect of the child’s hearing was the discrepancy between the monaural and the binaural results. That is, when assessed binaurally she often presented with a mild to moderate mixed loss and, when assessed monaurally, she showed a moderate to severe mixed loss for the right ear and a severe mixed loss for the left ear. Over time, the discrepancy between the monaural and binaural results changed. When assessed binaurally, the loss decreased to normal low frequency hearing sloping to a mild high frequency loss. When assessed monaurally, the most recent results showed a mild loss for the right ear and a moderate loss for the left ear. This discrepancy between binaural and monaural results was evident for both aided and unaided tests. For the most recent thresholds, the binaural results were consistent with the right monaural thresholds for the first time over the four and a half years. Parental reports of the child’s hearing were consistent with the binaural clinical results. This case indicates the need for audiologists to (1) carefully monitor the hearing of children with ACC, (2) obtain monaural and binaural hearing and aided thresholds results, and (3) compare these children’s functional abilities with the objective test results obtained. This case does question whether hearing aids are appropriate for children with ACC. If hearing aids are deemed to be appropriate, then hearing aids with compression characteristics should be considered.

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Recent research support sLocke's (1976) model of facet satisfaction in which the range of affect of objectively defined facet descriptions is moderated by subjective evaluations of facet importance (McFarlin & Rice, 1992). This study examined the utility of Locke's moderated model of face t satisfaction for the prediction of organizationally important global measures of job satisfaction. A large dataset of two groups of workers allowed testing over different time periods and across a broad range of satisfaction measures. The hypothesis derived from Locke's model, that global satisfaction would represent a linear function of facet satisfaction (i.e., facet description x facet importance), was not supported. Instead, a simple (have-want) discrepancy model (operationalized as facet description) provided the most consistent set of predictors. The results suggests that workers, when providing global measures of job satisfaction, may use cognitive heuristics to reduce the complexity of facet description x importance calculations. The implications of these data for Locke's model and directions for future research are outlined.

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Australia's rangelands are experiencing a post-productivist transition at a tempo comparable to Western Europe's, but in contexts that ensure marked divergence in impulses, actors, processes and outcomes. In Australia's most marginal lands, a flimsy mode of pastoral occupance is being displaced by renewed indigenous occupance, conservation and tourism, with significant changes in land ownership, property rights, investment sources and power relations, but also with structural problems arising from fugitive income streams. The sharp delineation between structurally coherent commodity-oriented regions and emerging amenity-oriented regions can provisionally be mapped at a national scale. A comparison of Australia with Western Europe indicates that three distinct but interconnected driving forces are propelling the rural transition, namely: agricultural overcapacity; the emergence of amenity-oriented uses; and changing societal values.

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Objective: To assess the (i) benefits, (ii) harms and (iii) costs of continuing mammographic screening for women 70 years and over. Data sources and synthesis: (i) We conducted a MEDLINE search (1966 - July 2000) for decision-analytic models estimating life-expectancy gains from screening in older women. The five studies meeting the inclusion criteria were critically appraised using standard criteria. We estimated relative benefit from each model's estimate of effectiveness of screening in older women relative to that in women aged 50-69 years using the same model. (ii) With data from BreastScreen Queensland, we constructed balance sheets of the consequences of screening for women in 10-year age groups (40-49 to 80-89 years), and (iii) we used a validated model to estimate the marginal cost-effectiveness of extending screening to women 70 years and over. Results: For women aged 70-79 years, the relative benefit was estimated as 40%-72%, and 18%-62% with adjustment for the impact of screening on quality of life. For women over 80 years the relative benefit was about a third, and with quality-of-life adjustment only 14%, that in women aged 50-69 years. (ii) Of 10 000 Australian women participating in ongoing screening, about 400 are recalled for further testing, and, depending on age, about 70-112 undergo biopsy and about 19-80 cancers are detected. (iii) Cost-effectiveness estimates for extending the upper age limit for mammographic screening from 69 to 79 years range from $8119 to $27 751 per quality-adjusted life-year saved, which compares favourably with extending screening to women aged 40-49 years (estimated at between $24 000 and $65 000 per life-year saved). Conclusions: Women 70 years and over, in consultation with their healthcare providers, may want to decide for themselves whether to continue mammographic screening. Decision-support materials are needed for women in this age group.