1000 resultados para Rooke, John G.


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Background There are few data regarding the effectiveness of remote monitoring for older people with heart failure. We conducted a post-hoc sub-analysis of a previously published large Cochrane systematic review and meta-analysis of relevant randomized controlled trials to determine whether structured telephone support and telemonitoring were effective in this population. Methods A post hoc sub-analysis of a systematic review and meta-analysis that applied the Cochrane methodology was conducted. Meta-analyses of all-cause mortality, all-cause hospitalizations and heart failure-related hospitalizations were performed for studies where the mean or median age of participants was 70 or more years. Results The mean or median age of participants was 70 or more years in eight of the 16 (n=2,659/5,613; 47%) structured telephone support studies and four of the 11 (n=894/2,710; 33%) telemonitoring studies. Structured telephone support (RR 0.80; 95% CI=0.63-1.00) and telemonitoring (RR 0.56; 95% CI=0.41-0.76) interventions reduced mortality. Structured telephone support interventions reduced heart failure-related hospitalizations (RR 0.81; 95% CI=0.67-0.99). Conclusion Despite a systematic bias towards recruitment of individuals younger than the epidemiological average into the randomized controlled trials, older people with heart failure did benefit from structured telephone support and telemonitoring. These post-hoc sub-analysis results were similar to overall effects observed in the main meta-analysis. While further research is required to confirm these observational findings, the evidence at hand indicates that discrimination by age alone may be not be appropriate when inviting participation in a remote monitoring service for heart failure.

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Background Despite the commonality of cough and its burden, there are no published data on the relationship between atopy or sex on objectively measured cough frequency or subjective cough scores in children. In 202 children with and without cough, we determined the effect of sex and atopy on validated cough outcome measurements (cough receptor sensitivity [CRS], objective cough counts, and cough scores). We hypothesized that in contrast to adult data, sex does not influence cough outcome measures, and atopy is not a determinant of these cough measurements. Methods We combined data from four previous studies. Atopy (skin prick test), the concentration of capsaicin causing two and five or more coughs (C2 and C5, respectively), objectively measured cough frequency, and cough scores were determined and their relationship explored. The children’s (93 girls, 109 boys) mean age was 10.6 years (SD 2.9), and 56% had atopy. Results In multivariate analysis, CRS was influenced by age (C2 coefficient, 5.9; P = .034; C5 coefficient, 29.1; P = .0001). Atopy and sex did not significantly influence any of the cough outcomes (cough counts, C2, C5, cough score) in control subjects and children with cough. Conclusions Atopy does not influence important cough outcome measures in children with and without chronic cough. However, age, but not sex, influences CRS in children. Unlike adult data, sex does not affect objective counts or cough score in children with and without chronic cough. Studies on cough in children should be age matched, but matching for atopic status and sex is less important.

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Exotic species dominate many communities; however the functional significance of species’ biogeographic origin remains highly contentious. This debate is fuelled in part by the lack of globally replicated, systematic data assessing the relationship between species provenance, function and response to perturbations. We examined the abundance of native and exotic plant species at 64 grasslands in 13 countries, and at a subset of the sites we experimentally tested native and exotic species responses to two fundamental drivers of invasion, mineral nutrient supplies and vertebrate herbivory. Exotic species are six times more likely to dominate communities than native species. Furthermore, while experimental nutrient addition increases the cover and richness of exotic species, nutrients decrease native diversity and cover. Native and exotic species also differ in their response to vertebrate consumer exclusion. These results suggest that species origin has functional significance, and that eutrophication will lead to increased exotic dominance in grasslands.

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Factors that affect the settleability of seawater neutralised bauxite refinery residues are poorly understood, in particular, the settleability of precipitates in the absence of red mud and those formed with different alumina/caustic (AC) ratios. The influence of temperature, AC ratio, caustic concentration and the volumetric ratio of seawater on the settleability of seawater neutralisation precipitates and their respective compositions and stabilities have been determined. An array of techniques have been used to determine the composition and stability of precipitates and include pH, conductivity, inductively coupled plasma optical emission spectroscopy, infrared spectroscopy and X-ray diffraction. Temperature has been shown to have a significant influence on the settleability and calcium carbonate phase distributions in precipitates, as well as the overall stability of the precipitates. More complex phase compositions have also been found for Bayer liquors with lower AC ratios. The caustic concentration and temperature of the reaction have the greatest influence on the settling efficiency of the precipitates. Assessments on the chemical stability of the precipitates, precipitate settleability and discharge water quality have been made. In addition, productivity and environmental impacts caused by changes in precipitate settleability have also been considered.

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Historical stocking methods of continuous, season-long grazing of pastures with little account of growing conditions have caused some degradation within grazed landscapes in northern Australia. Alternative stocking methods have been implemented to address this degradation and raise the productivity and profitability of the principal livestock, cattle. Because information comparing stocking methods is limited, an evaluation was undertaken to quantify the effects of stocking methods on pastures, soils and grazing capacity. The approach was to monitor existing stocking methods on nine commercial beef properties in north and south Queensland. Environments included native and exotic pastures and eucalypt (lighter soil) and brigalow (heavier soil) land types. Breeding and growing cattle were grazed under each method. The owners/managers, formally trained in pasture and grazing management, made all management decisions affecting the study sites. Three stocking methods were compared: continuous (with rest), extensive rotation and intensive rotation (commonly referred to as 'cell grazing'). There were two or three stocking methods examined on each property: in total 21 methods (seven continuous, six extensive rotations and eight intensive rotations) were monitored over 74 paddocks, between 2006 and 2009. Pasture and soil surface measurements were made in the autumns of 2006, 2007 and 2009, while the paddock grazing was analysed from property records for the period from 2006 to 2009. The first 2 years had drought conditions (rainfall average 3.4 decile) but were followed by 2 years of above-average rainfall. There were no consistent differences between stocking methods across all sites over the 4 years for herbage mass, plant species composition, total and litter cover, or landscape function analysis (LFA) indices. There were large responses to rainfall in the last 2 years with mean herbage mass in the autumn increasing from 1970 kg DM ha(-1) in 2006-07 to 3830 kg DM ha(-1) in 2009. Over the same period, ground and litter cover and LFA indices increased. Across all sites and 4 years, mean grazing capacity was similar for the three stocking methods. There were, however, significant differences in grazing capacity between stocking methods at four sites but these differences were not consistent between stocking methods or sites. Both the continuous and intensive rotation methods supported the highest average annual grazing capacity at different sites. The results suggest that cattle producers can obtain similar ecological responses and carry similar numbers of livestock under any of the three stocking methods.

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Pasture rest is a possible strategy for improving land condition in the extensive grazing lands of northern Australia. If pastures currently in poor condition could be improved, then overall animal productivity and the sustainability of grazing could be increased. The scientific literature is examined to assess the strength of the experimental information to support and guide the use of pasture rest, and simulation modelling is undertaken to extend this information to a broader range of resting practices, growing conditions and initial pasture condition. From this, guidelines are developed that can be applied in the management of northern Australia’s grazing lands and also serve as hypotheses for further field experiments. The literature on pasture rest is diverse but there is a paucity of data from much of northern Australia as most experiments have been conducted in southern and central parts of Queensland. Despite this, the limited experimental information and the results from modelling were used to formulate the following guidelines. Rest during the growing season gives the most rapid improvement in the proportion of perennial grasses in pastures; rest during the dormant winter period is ineffective in increasing perennial grasses in a pasture but may have other benefits. Appropriate stocking rates are essential to gain the greatest benefit from rest: if stocking rates are too high, then pasture rest will not lead to improvement; if stocking rates are low, pastures will tend to improve without rest. The lower the initial percentage of perennial grasses, the more frequent the rests should be to give a major improvement within a reasonable management timeframe. Conditions during the growing season also have an impact on responses with the greatest improvement likely to be in years of good growing conditions. The duration and frequency of rest periods can be combined into a single value expressed as the proportion of time during which resting occurs; when this is done the modelling suggests the greater the proportion of time that a pasture is rested, the greater is the improvement but this needs to be tested experimentally. These guidelines should assist land managers to use pasture resting but the challenge remains to integrate pasture rest with other pasture and animal management practices at the whole-property scale.

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The problem of excitation of 11zultilayercd-graded-dielectric-coatedc onductor by a magnetic ring source is fornzulated in the ,form of a contour integrul which is rolved by using the method of steepest descent. Numerical evaluation of launching efiiency shows that high value of about 90 percent can be attained by choosing proper dimensions of the launcher with respect to the dimension of the surface wave line.

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A report of the design, development ana periom~ance characteristics of a Q-band (8 nim) confoal. mned, aielectric lens beam waveguide is presented.

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Consideration is given to a 25-foot long Q-band (8 mm) confocal, zoned dielectric lens beam waveguide. Numerical expressions for the axial and radial fields are presented. The experimental set-up consisted of uniformly spaced zoned dielectric lenses, a transmitting horn and a receiving horn. It was found that: (1) the wave beam is reiterated when confocal, zoned dielectric lenses act as phase transformers in place of smooth surfaced transformers in beam waveguides; (2) the axial field is oscillatory near the source and the oscillation persists for about 25 cm from the source; (3) the oscillation disappears after one lens is used; (4) higher order modes with higher attenuation rates die out faster than fundamental modes; (5) phase transformers do not alter beam modes; (6) without any lens the beam cross-section broadens significantly in the Z-direction; (7) with one lens the beam exhibits the reiteration phenomenon; and (8) inserting a second lens on the axial and cross-sectional field distribution shows further the reiteration principle.

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The submersed plants hydrilla (Hydrilla verticillata (L.f.) Royle) and elodea (Elodea canadensis Rich.) are both members of the Hydrocharitaceae family and cause problems in waterways throughout the world. Diquat (6,7-dihydrodipyrido[1,2-α:2’,1’-c]pyrazinediium dibromide) is a contact herbicide used to control nuisance submersed and floating aquatic macrophytes. There is no readily available information in the literature on the control of elodea under various diquat concentration and exposure times (CET) and other than a study by Van et. al 1987, little on hydrilla. Since CET relationships are critical in controlling submersed plants in areas influenced by water exchange, this study was designed to evaluate the efficacy of diquat on hydrilla and elodea under various CET scenarios. (PDF has 3 pages.)

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ENGLISH: The egg of the anchoveta, Cetengraulis mysticetus (¼nther), was identified in the Gulf of Panama by its size, difference in diurnal period of spawning, seasonal occurrence (October to January) and relative abundance. It is pelagic, translucent and oval with mean dimensions of 1.166 mm. and 0.558 mm. for the long and short axes respectively. The egg membrane is unsculptured, the yolk mass is markedly segmented, and no oil globule or pigmentation is present. It was not found in the plankton from mid-January 1957 until the latter part of the following September; during this period the gonads of the anchoveta were immature. Only one other anchovy egg, spawned during the same diurnal period, is sufficiently similar in dimensions to be confused with that of the anchoveta; however, it is slightly smaller. SPANISH: El huevo de la anchoveta, Cetengraulis mysticetus (¼nther), fué identificado en el Golfo de Panamá por su tamaño, diferencias en el período diario de desove, su abundancia en la temporada (de octubre a enero) y por su abundancia relativa. El huevo es pelágico, translúcido, oval y con dimensiones promedio de 1.166 mm. y 0.558 mm. para los ejes largo y corto, respectivamente. La membrana es lisa, el vitelo está francamente segmentado y no posee ninºn glóbulo graso o pigmentación. El huevo de la anchoveta no se encontró en el plancton en el período comprendido entre mediados de enero y fines de septiembre de 1957; durante este lapso las ³nadas estuvieron inactivas.

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(PDF contains 3 pages.)

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(PDF contains 3 pages.)

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As background to a study of the application of astracods in environmental archaeology, a number of sites in South Wales were visited and sampled. Sites included seven broad environmental categories consisting of lakes, permanent ponds, non-permanent ponds, semi-static canals and reens (drainage ditches), non-permanent small lotic water-bodies, permanent fast-flowing waters and wells. In all, twenty-three species were recorded, and with one exception all belonged to the predominately freshwater Cypridoidea. Overall the most commonly encountered species in South Wales was Cypria ophthalmica. Comparing finds with earlier records, it would appear that Ilyocypris bradyi, Candona pratensis, Eucypris lilljeborgi, Herpetocypris chevreuxi, Potamocypris variegata, P. similis and P. pallida are new additions to the Welsh fauna.