bluuebunny/crossref_metadata_2025 huggingface dataset:
Polymorphism and Thermal Behaviour of Syndiotactic Poly(propylene)/Carbon Nanotube Composites
Authors: Sarno Maria , Gorrasi Giuliana , Sannino Diana , Sorrentino Andrea , Ciambelli Paolo , Vittoria Vittoria
Published: November 2004

Summary: Nanocomposite materials were obtained by blending multi‐wall carbon nanotubes (CN), obtained by acetylene catalytic chemical vapour deposition (CVD) on Co/Fe‐modified NaY zeolite, with syndiotactic poly(propylene) (sPP). The nanotubes, well dispersed in the polymer matrix, favour the crystallization of the sPP helical chains and significantly improve the sPP thermal stability either in nitrogen or in air. The morphology of the sPP affects the behaviour of the sPP degradation in air.

Thermogravimetric analysis in air of pure sPP and the nanocomposite material.

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Thermogravimetric analysis in air of pure sPP and the nanocomposite material.
On solving large strain hyperelastic problems with the natural element method
Authors: Calvo B. , Martinez M. A. , Doblaré M.
Published: November 2004

In this paper, an extension of the natural element method (NEM) is presented to solve finite deformation problems. Since NEM is a meshless method, its implementation does not require an explicit connectivity definition. Consequently, it is quite adequate to simulate large strain problems with important mesh distortions, reducing the need for remeshing and projection of results (extremely important in three‐dimensional problems). NEM has important advantages over other meshless methods, such as the interpolant character of its shape functions and the ability of exactly reproducing essential boundary conditions along convex boundaries. The α‐NEM extension generalizes this behaviour to non‐convex boundaries. A total Lagrangian formulation has been employed to solve different problems with large strains, considering hyperelastic behaviour. Several examples are presented in two and three dimensions, comparing the results with the ones of the finite element method. NEM performs better showing its important capabilities in this kind of applications. Copyright © 2004 John Wiley & Sons, Ltd.
Tunable Whispering Gallery Mode Emission from Quantum‐Dot‐Doped Microspheres
Authors: Gómez Daniel E. , Pastoriza‐Santos Isabel , Mulvaney Paul
Published: November 2004

We describe the synthesis of quantum‐dot (QD) doped silica microspheres and a method by which it is possible to fine‐tune the position of the whispering gallery modes (WGMs) produced by the fluorescence emission of CdSe@ZnS doped silica microspheres (5.06 μm in diameter). The method is based on small perturbations to the sphere's refractive index caused by adsorption of thin layers of polyelectrolytes and modification of the radial position of the nanocrystals within the microsphere by means of deposited silica shells.
Using software trails to reconstruct the evolution of software
Authors: German Daniel M.
Published: November 2004

This paper describes a method to recover the evolution of a software system using its software trails: information left behind by the contributors to the development process of the product, such as mailing lists, Web sites, version control logs, software releases, documentation, and the source code. This paper demonstrates the use of this method by recovering the evolution of Ximian Evolution, a mail client for Unix. By extracting useful facts stored in these software trails and correlating them, it was possible to provide a detailed view of the history of this project. This view provides interesting insight into how an open source software project evolves and some of the practices used by its software developers. Copyright © 2004 John Wiley & Sons, Ltd.
Plasmodium falciparumookinete invasion of the midgut epithelium ofAnopheles stephensiis consistent with the Time Bomb model
Authors: BATON L. A. , RANFORD-CARTWRIGHT L. C.
Published: November 2004

Plasmodium falciparumgametocytes grownin vitrowere fed through membrane feeders to laboratory-rearedAnopheles stephensimosquitoes. Intact midguts, including entire bloodmeal contents, were removed between 24 and 48 h post-bloodfeeding. Giemsa-stained histological sections were prepared from the midguts and examined by light microscopy. Contrary to previous reports, ookinetes were clearly visible within midgut epithelial cells, demonstrating intracellular migration across the midgut wall. Ookinetes entered epithelial cells through the lateral apical membrane at sites where 3 adjacent cells converged. There was no evidence for the existence of a morphologically distinct group of epithelial cells preferentially invaded by ookinetes. However, ookinete penetration was associated with significant morphological changes to invaded cells, including differential staining, condensation and fragmentation of the nucleus, vacuolization, loss of microvilli and various degrees of extrusion into the midgut lumen. Epithelial cells completely separated from the midgut wall were found within the midgut lumen. These cells were associated with invading parasites suggesting that ookinete penetration resulted in complete ejection of invaded cells from the midgut wall. Small clusters of morphologically altered midgut cells and invading parasites spanning the membranes of adjacent abnormal epithelial cells were observed, consistent with intracellular movement of ookinetes between neighbouring midgut cells. Extruded epithelial cells were also observed rarely in uninfected midguts. Epithelial cell extrusion, therefore, may be a general mechanism of tissue repair through which damaged cells are removed from the midgut wall rather than a parasite-specific response. These observations demonstrate that human malaria parasite infection of mosquitoes is consistent with, and provides further support for, the Time Bomb model of ookinete invasion of the mosquito midgut epithelium previously proposed for rodent malaria parasites.
Evolutionary relationships between 15 Plasmodium species from New and Old World primates (including humans): a 18S rDNA cladistic analysis
Authors: LECLERC M. C. , HUGOT J. P. , DURAND P. , RENAUD F.
Published: November 2004

We present a new phylogenetic analysis of 15 primate Plasmodium species based on 18S rDNA sequences including new sequences of Plasmodium coatneyi, P. fieldi, P. gonderi, P. hylobati and P. simium. The results are discussed in the context of the parasite host species and their geographical distribution. Contrary to other phylogenies constructed with this 18S rDNA molecule, we observed that the topology of phylogenetic trees was not affected either by the quality of the nucleotide matrices, or by the species present in the outgroup. This analysis showed the following. (1) The polyphyly of human Plasmodium is confirmed. (2) The monophyly of Plasmodium from Old World monkeys is confirmed by the new added sequences and P. gonderi, an African species, possibly could be at the root of this group. (3) The most parsimonious biogeographical hypothesis is that P. vivax originated in Asia; thus, its related species P. simium appears to be derived through a transfer from the human P. vivax to New World monkey species in South America. (4) Sampling efforts of non-human primate Plasmodium could permit improvement of the knowledge of primate Plasmodium phylogeny and also consideration of the risks of malaria emergence from monkey reservoirs.
Social networks, ethnicity and public home-care utilisation
Authors: LITWIN HOWARD
Published: November 2004

This article examines the relationships between support networks, ethnicity and the utilisation of formal care services, taking into account background characteristics and functional health status among 3,403 older people in Israel. Data were drawn from a national survey in 1997 of people aged 60 or more years. The outcome variable was the use of publicly-financed personal care or homemaking services. About 15 per cent of the study population made use of such home care. Six informal support network constellations were identified by applying cluster analysis to key criterion variables that reflect the inter-personal milieu. The resultant network types were: community-clan, family-focused, diverse, friend-focused, neighbour-focused, and restricted networks. Binary logistic regression revealed that the use of formal home-care services was significantly associated with a respondent's age, gender, functional level and informal support network type (Nagelkerke R2=0.39). No association was found between home-care utilisation and a respondent's ethnicity (Arab, Jew, and new Russian immigrant), income or education. The results show that publicly-financed formal care services were utilised more frequently by older-old persons, women, functionally impaired individuals and people embedded in the neighbour-focused and restricted networks (and to a lesser degree, in the diverse and friend-focused networks). Neighbour-focused and restricted network types were characterised by fewer informal support resources at their disposal than the other types. Thus, formal home care was sought more often in cases in which the informal sources of support had less capacity to provide ongoing informal care.
Zonal circulation across 52°W in the North Atlantic
Authors: Hall Melinda M. , Joyce Terrence M. , Pickart Robert S. , Smethie William M. , Torres Daniel J.
Published: November 2004

In July–August 1997, a hydrographic/Acoustic Doppler Current Profiler (ADCP)/tracer section was occupied along 52°W in the North Atlantic as part of the World Ocean Circulation Experiment Hydrographic Program. Underway and lowered ADCP (LADCP) data have been used to reference geostrophic velocities calculated from the hydrographic data; additional (small) velocity adjustments provided by an inverse model, constraining mass and silicate transports in 17 neutral density layers, yield the absolute zonal velocity field for 52°W. We find a vigorous circulation throughout the entire section, with an unusually strong Gulf Stream (169 Sv) and southern Deep Western Boundary Current (DWBC; 64 Sv) at the time of the cruise. At the northern boundary, on the west side of the Grand Banks of Newfoundland, we find the westward flowing Labrador Current (8.6 Sv), whose continuity from the Labrador Sea, east of our section, has been disputed. Directly to the south we identify the slopewater current (12.5 Sv eastward) and northern DWBC (12.5 Sv westward). Strong departures from strictly zonal flow in the interior, which are found in the LADCP data, make it difficult to diagnose the circulation there. Isolated deep property extrema in the southern portion, associated with alternating bands of eastward and westward flow, are consistent with the idea that the rough topography of the Mid‐Atlantic Ridge, directly east of our section, causes enhanced mixing of Antarctic Bottom Water properties into overlying waters with distinctly different properties. We calculate heat and freshwater fluxes crossing 52°W that exceed estimates based on air‐sea exchanges by a factor of 1.7.
Jupiter's and Saturn's convectively driven banded jets in the laboratory
Authors: Read P. L. , Yamazaki Y. H. , Lewis S. R. , Williams P. D. , Miki‐Yamazaki K. , Sommeria J. , Didelle H. , Fincham A.
Published: November 2004

The banded patterns of cloud and wind are among the most striking features of the atmospheres of Jupiter and Saturn, but their dynamical origin remains poorly understood. Most approaches towards understanding zonation so far (also in the terrestrial oceans) have used highly idealized models to show that it might originate from dynamical anisotropy in a shallow turbulent fluid layer due to the planetary β‐effect. Here we report the results of laboratory experiments, conducted on a 14‐m diameter turntable, which quantitatively confirm that multiple zonal jets may indeed be generated and maintained by this mechanism in the presence of deep convection and a topographic β‐effect. At the very small values of Ekman number (≤2 × 10−5) and large local Reynolds numbers (≥2000, based on jet scales) achieved, the kinetic energy spectra suggest the presence of both energy‐cascading and enstrophy‐cascading inertial ranges in addition to the zonation near twice the Rhines wave number.
Rocket observations of structured upper hybrid waves at fuh = 2fce
Authors: Samara M. , LaBelle J. , Kletzing C. A. , Bounds S. R.
Published: November 2004

The HIgh Bandwidth Auroral Rocket (HIBAR), launched into active pre‐midnight aurora, encountered two bursts of 2–10 mV/m upper hybrid waves just below fuh = 2fce at approximately 377 and 390 km altitude. These waves occur in association with a density “shoulder” and enhancement, respectively. The waves show several bands of frequency structure with 4–8 kHz spacings and, within these, bands of frequency sub structure with 1–2 kHz spacings. At the time of the waves, the measured electron distribution indicates wave instability for frequencies 1–1.2% percent below the electron cyclotron harmonic. These results agree qualitatively with theoretical work predicting banded structure associated with upper hybrid waves trapped in density enhancements.
Measurements of 210Pb and 7Be in China and their analysis accompanied with global model calculations of 210Pb
Authors: Lee H. N. , Wan Guojiang , Zheng Xiangdong , Sanderson Colin G. , Josse Beatrice , Wang Shilu , Yang Wei , Tang Jie , Wang Changsheng
Published: November 2004

Previous global models generally simulated high concentrations of 210Pb in the surface air over China. Measured data of 210Pb are needed in order to examine the accuracy and performance of the models. We collected the first‐ever set of surface air radionuclide measurements of 210Pb and 7Be at Guiyang (26.57°N, 106.72°E, 1080 m above sea level) on the east of the Himalayas in Guizhou Province and at Mt. Waliguan (36.29°N, 100.90°E, 3816 m above sea level), a Global Atmosphere Watch station for the World Meteorological Organization, on the Qinghai‐Tibetan plateau extending from the Himalayas in Qinghai Province, China. These measurements were carefully analyzed for data assurance and quality control and were used for validating models. The patterns for the variations in both measured 210Pb and 7Be at the Guiyang site have been shown to be consistent. In this case the increase of 7Be concentration was the result of the weak subsidence of air developed at the periphery of the high‐pressure system. Because of the weak subsidence the boundary layer turbulence could mix the upward transport of 210Pb, thus increasing 210Pb concentration. The ratio of 7Be/210Pb indicated a seasonal variability with rough monthly oscillation. The ratio peaks were in spring and summer when the convective activities were significant. The 210Pb levels measured at Mt. Waliguan, located at the peak of the mountain, could be attributed to the long‐range transport of 222Rn that decays to 210Pb, whereas the 7Be concentration varied directly with the local airflow passing over the site. We found that it was not appropriate to use the ratio of 7Be/210Pb for analysis of vertical transport exchange processes at the high‐altitude Mt. Waliguan site because of the long‐range transport of 210Pb that occurred at the site. For the purpose of model validation we have simulated the global transport of 210Pb for the year 2002 by using a comprehensive multiscale three‐dimensional global chemical transport model developed by Météo France. It was found by comparing model results with measurements that the model generally performed poorly for the calculations of 210Pb concentrations in China. The underestimates of model results could be the result of the unidentified high radon sources over China. However, the model was able to reproduce the variations of the 210Pb concentrations.
Nitrogen nutrition of cereals in a short-term rotation. I. Single season treatments as a source of nitrogen for subsequent cereal crops
Authors: Papastylianou I , Puckridge DW , Carter ED
Published: November 2004

The residual effects of one season of five cultural treatments common in southern Australian dryland farming were examined with respect to soil water and nitrogen, and the production of cereals in the next two years. The initial treatments were medic or subterranean clover pasture, faba beans, oats or bare fallow. In the second year barley, wheat and triticale were grown on the same plots, with 0,30,60 or 90 kg ha-1 of fertilizer nitrogen. Wheat was sown over the whole area for the third season. The medic and subterranean clover pastures contributed approximately 100 kg ha-1 of nitrogen in top growth, but this remained on the surface until cultivation. Oats and fallow plots declined in total soil nitrogen by about 70 kg ha-1. The nitrogen content of the faba bean stubble showed that this crop has the potential of providing equivalent nitrogen to a good legume pasture. At the beginning of the second season the previous plots of fallow, beans, subterranean clover and medic had 36,27, 14 and 12 mm more water in the top metre of soil than oat plots. Cereals after oats apparently did not respond to fertilizer nitrogen because of the dry conditions, but on other plots the yield response was not proportional to the additional water. Although first year treatments affected growth of the three cereals in the second season, the new cereal, triticale, showed no evidence of different adaptation to growing conditions than wheat or barley. The effects of first and second year treatments carried through to the wheat crop in the third season. There were marked differences in nitrogen availability, but evidence that the second crop was depleting soil nitrogen reserves. Nitrogen from first year legume residues was available earlier in the season than second year fertilizer nitrogen which had been leached from the surface soil.
The nutrition of ruminants grazing native and improved pastures. V. Effects of stocking rate and soil ingestion on the copper and selenium status of grazing sheep
Authors: Langlands JP , Bowles JE , Donald GE , Smith AJ
Published: November 2004

In experiment 1, sheep ranging in age from newly born to 112 months had greater hepatic copper concentrations at 10 than at 20 sheep/ha but differences in selenium concentration varied between age groups. In experiment 2, sheep aged 29 months were grazed at 10 and 20 sheep/ha and were subjected to liver biopsy at monthly intervals. Hepatic selenium concentrations averaged 0.38 mg/kg DM at the high and 0.56 mg/kg DM at the low stocking rate. Blood selenium concentration was also greater at the lower stocking rate. In experiment 3, grazing sheep were supplemented with two soils collected from areas which supported sheep with high (HS) and low (LS) blood selenium concentrations. Soil HS slightly increased selenium concentration in blood and soil LS had no effect; hepatic copper levels were not affected by giving either soil.
Introduction of vesicular arbuscular mycorrhizal fungi into agricultural soils
Authors: Abbott LK , Robson AD , Hall IR
Published: November 2004

Two species of vesicular arbuscular (VA) mycorrhizal fungi were introduced into agricultural soils at four field sites. Three sites were chosen, on the basis of a previous survey, to give a range in the expected extent and rate of mycorrhizal formation by the indigenous fungi. The fourth site had recently been cleared of natural vegetation and ploughed. The success of inoculation with Glomus fasciculatum and G. monosporum was measured by estimating the extent of mycorrhizas formed by the inoculant fungi and by recording growth of subterranean clover. The effects of inoculating with these two mycorrhizal fungi on the development of mycorrhizas formed by the indigenous fungi were also followed in detail. At two sites, infection by G. fasciculatum was increased in the plots where this species was added in the inoculum. Growth was temporarily enhanced after inoculation with G. fasciculatum at one of these sites. This corresponded with a temporary increase in the percentage of root length infected as a result of inoculation. Plants grown at the two sites where G. fasciculatum became established had a slower rate of development of infection by the indigenous VA mycorrhizal fungi compared with that formed by the indigenous species at the other two sites.
Effects of short periods of exposure to high temperature on the phenology and shoot apex development of wheat cv. Sonora 64
Authors: Amores-Vergara E , Cartwright PM
Published: November 2004

Wheat (cv. Sonora 64) was exposed to high temperatures (27�C) during six developmental stages and compared with growth of controls at continuous high (27�C) and continuous low (17�C) temperatures. Time from sowing to maturity was reduced more by later exposures to high temperature, especially anthesis to maturity. High temperatures in phases I, IIA and IIB promoted a higher fraction of fertile florets to set grain, but total grain yield was lower because the number of fertile florets per ear and weight of individual grains decreased. The reasons for this response are examined in terms of the flowering apex.
Leaf growth and senescence in Urochloa mosambicensis and U. oligotricha in a seasonally dry tropical environment
Authors: McIvor JG
Published: November 2004

Rates of leaf appearance, expansion and senescence were followed in swards of Urochloa mosambicensis (cv. Nixon, CPI 46876 and CPI 47167) and U. oligotricha (CPI 45607, CPI 47122 and CPI 47124) growing near Townsville, northern Queensland over a 3-year period. Rates of leaf appearance and expansion were greater for U. mosambicensis than U, oligotricha, but there were no differences between accessions within species. Rates of leaf appearance were high (c. 2 leaves tiller-1 week-1) at the start of the growing season and then declined. The weekly changes in rate of leaf appearance were closely related to changes in a water index (ratio of estimated evapotranspiration to potential evapotranspiration). Leaves of U. oligotricha commenced to senesce before those of U. mosambicensis, but their subsequent rate of decline was slower and so there was overlap between species for length of leaf life. Senescence was most rapid under favourable growing conditions and was more closely correlated with moisture supply than with temperature. The nitrogen concentration of green leaves declined substantially before there was any death, but the green portion of leaves always had a higher nitrogen concentration than the dead portion of a similar age.
Corrigendum - Growth and productivity of irrigated Sorghum bicolor (L. Moench) in Northern Australia. II. Low solar altitude as a possible constraint to productivity in the tropical dry season
Authors: Foale MA , Wilson GL , Coates DB , Haydock KP
Published: November 2004

A growth study was carried out during the dry season on irrigated grain sorghum cultivar NK 300F at latitude 16�S. in northern Australia. The apparent efficiency of the canopy in the photosynthetic conversion of solar radiation increased progressively in high density stands between June and September, while low density stands showed no change. An hypothesis is advanced that the rise in canopy efficiency was due to increasing solar altitude combining with a suitable canopy structure at high density to give increased light penetration into the canopy. A parameter named weighted mean solar altitude (WMSA) is used in conjunction with noon solar altitude (NSA) to assist in the interpretation of published models of light penetration. This solar altitude effect, if verified by further work, would lower the expectations, based on mean daily solar radiation, for dry season yield of irrigated sorghum and possibly other cereals in the semi-arid tropics.
The effect of different proportions of Leucaena leucocephala in the diet of cattle on growth, feed intake, thyroid function and urinary excretion of 3-hydroxy-4(1H)-pyridone
Authors: Jones RJ , Hegarty MP
Published: November 2004

Steers were fed in pens on diets containing 0, 10, 20, 40, 67 and 100% Leucaena for 112 days. The remainder of the diet was a good quality sorghum hay. Liveweight change, feed intake, mimosine intake, urinary output of 3-hydroxy-4(1H)-pyridone (DHP), serum thyroxine (T4), serum triiodothyronine (T3) and effective thyroxine ratio (ETR) were measured. Steers on the 67 and 100% Leucaena diets had low feed intakes (40-50 g (kg LW)-a 75), lost weight and were severely hypothyroid. Steers on the 0, 10 and 20% Leucaena had intakes of 80-90 g (kg LW)-a 75, gained liveweight at 0.3-0.5 kg day-' and showed normal thyroid function. Steers on the 40% Leucaena diet had high feed intakes and grew well initially, but subsequently their feed intakes and rates of liveweighr gain declined. Reduced feed intake was associated with serum T3 levels below 1.0 nmol l-1. DHP excretion in the urine was linearly related to Leucaena and mimosine intake (P < 0.01). Recoveries of mimosine eaten, as DHP in the urine, varied from 33% with the 10% Leucaena diet to 55% with full Leucaena feeding. Feed intake declined as the proportion of Leucaena in the diet increased, but recovery of appetite was rapid when steers were transferred to an all sorghum hay ration. It is concluded that diets containing less than 1 % mimosine on a DM basis have little adverse effect on thyroid function or feed intake, whereas above this level hypothyroidism and low feed intakes may occur. Under Australian conditions Leucaena can only safely be used as a supplement (<30%) to roughage diets, rather than as a major dietary component, until some solution to the toxicity problem is found.
Influence of environmental factors on the development of the anthracnose diseases of Stylosanthes spp
Authors: Irwin JAG , Cameron DF , Ratcliff D
Published: November 2004

The influence of temperature, period of leaf wetness after inoculation, and relative humidity on the development of the type A and type B diseases of Stylosanthes spp. caused by Colletotrichum gloeosporioides was studied in controlled environment cabinets. Severe disease of both types developed in plants incubated at temperatures of 20-30�C, and given 24 h of leaf wetness after inoculation. Provided these conditions were imposed, high levels of disease developed following the leaf wetness period, irrespective of the relative humidity (40-50% or >95%). High levels of disease developed for both the type A and type B combinations at temperatures in the range 20-3OoC, but only the type A disease developed at >34�C. Neither disease developed at constant temperatures of 15 or 37�C. The use of these results in the development of a model to predict field infection is discussed.
Physiology of growth and seed production in Lupinus angustifolius L. I. Effects on pod and seed set of controlled short duration high temperatures at flowering
Authors: Downes RW , Gladstones JS
Published: November 2004

Plants of Lupinus angustifolius cv. Unicrop, with branches excised to eliminate competition between branches and the primary inflorescence, were exposed to three temperature treatments: 33/28, 33/13 and 18/28�C. Each treatment continued for 1, 3 or 5 days, and was begun as flowers were starting to open, or 5 days before, or 10 days after that time. Control plants remained at 18/13�C throughout. Stress due to high day temperatures before flowering prevented early flowers from developing pods, but later flowers were able to compensate. Temperature stress as flowering began substantially reduced numbers of seed-containing pods, and little compensation was observed, either in later pod set or in seed number per pod. After flowering, high day temperatures did not affect the most developed pods, but ovule abortion reduced seed production in the less developed pods. These findings are discussed in relation to assimilate availability and hormone effects, and the adaptability of the narrow-leafed lupin plant is discussed in view of environmental restraints. Breeding implications are briefly considered.
A phenological evaluation of wheat for south-western Victoria
Authors: Crofts HJ , Gardner WK , Velthuis RG
Published: November 2004

Wheat lines and varieties known to vary phenologically were investigated in a serial sowing at two locations in south-western Victoria. They were classified into five categories: winter wheats, groups I and 11; semi-winter wheats; photoperiod-sensitive spring wheats; and relatively insensitive wheats. Only the winter wheats group I, and photoperiod-sensitive spring wheats were able to fully utilize the growing season available in the high rainfall areas of south-western Victoria. A system of cultivar evaluation in target environments, by the use of comparisons to near-isogenic lines in a reference environment, is discussed.
Corrigendum - Heterosis and breed effect on carcass traits of rams. 1. Carcass weight and component traits
Authors: Ch'ang TS , Evans R
Published: November 2004

A three-breed diallel mating design was used to generate 632 rams comprising three purebreds (Dorset Horn, Merino and Corriedale) and their six contemporary F1 crossbreds in the CSIRO Sheep Crossbreeding Experiment to provide materials for studying the heterosis and breed effects on carcass traits of intact rams maintained under pasture grazing conditions. The rams were slaughtered at an average age of 21 months, at which time their average (� s.e.) carcass weight was 28.4 � 0.2 kg. This paper, the first of a series, is concerned with estimation of the linear effects due to heterosis (h') and breed-transmitted effect (gI) and breed-maternal effect (gM) on cold carcass weight and weight components (edible meat, bones and excess fat trim) of the carcass. The results showed that, in general, gI was more important than gM. Whether evaluated as a purebred, or as a paternal or maternal breed, the Dorset Horn produced more edible meat per sheep than either the Merino or the Corriedale. In terms of excess fat trim, the Corriedale tended to be the most wasteful. A significant (P < 0.05) heterosis effect was observed on all traits under investigation, but its main impact was on excess fat trim, where the h1 varied with the specific breed combination and ranged from 10% to 30%, but averaged c. 24% for the whole population.
Comparative performance of five genotypes of Indonesian large ruminants. 2. Growth and development of non-carcass components
Authors: Moran JB , Wood JT
Published: November 2004

The weights of carcass and non-carcass components were recorded in 105 serially slaughtered bulls comprising Madura, Ongole, Bali, Grati (Friesian cross) and swamp buffaloes that had been fed diets containing 85 or 30% concentrate for up to 280 days. Huxley's allometric equation was used in its logarithmic form as the basis for covariance analyses of the data. Dressing percentages, in decreasing order, were Madura, Bali, Ongole, Grati and buffalo, and were inversely related to weights of gut contents, head, feet, hide and internal offal (pluck, liver, spleen and kidney and empty gut). Weights of abdominal fat depots were lowest in the Grati bulls. There were both genetic and dietary influences on the proportional development of components of the alimentary tract.
Nutritional evaluation of south-west Queensland pastures. 1. The botanical and nutrient content of diets selected by sheep grazing on Mitchell grass and mulga/grassland associations
Authors: McMeniman NP , Beale IF , Murphy GM
Published: November 2004

The botanical composition and nutrient content of diets selected by sheep grazing Mitchell grass (Astrebla spp.) and mulga (Acacia aneura)/grassland pastures in south-west Queensland were studied during a four-year period. Forbs, when present in the sward, contributed significantly to the diets on both grassland types. Under drought conditions grasses were the major components of the diets of sheep grazing Mitchell grassland pastures, while under similar conditions on the mulga/grassland pastures at least 35% of the diet was mulga (Acacia aneura); some mulga was present in the diet at all times. In general, the nutrient content of the green leaves of grasses and forbs growing on the mulga/ grassland association was similar, whereas on the Mitchell grass association green forbs had a higher nutrient concentration than did the leaves of green grasses. Both the grasses and forbs on the mulga/ grassland site had lower P and sodium concentrations than those on the Mitchell grassland site. When seasonal conditions were average to good the concentrations of all nutrients in the diets of sheep grazing the Mitchell grass association were judged to be adequate. However, when the pastures dried out the diets contained low concentrations of N (7.0 g/kg DM), P (0.9 g/kg DM), sodium (O.lg/kg DM) and copper (3.8 mg/kg DM). On the mulga/grassland site dietary concentrations of P and sodium were low at all times and under drought conditions the N:S ratio fell to 16.8:1. The concentrations of other nutrients in the diets were high enough to provide the sheep's theoretical requirements at all times.
The effect of foliar application of fulvic acid on water use, nutrient uptake and yield in wheat
Authors: Xudan X
Published: November 2004

The effect of foliar application of fulvic acid (FA) on water use, nutrient uptake and yield in wheat was studied in pot experiments and in field trials. FA reduced the stomatal conductance of well-watered plants in pots from ~0.80 to ~0.25 cm s-1. The stomatal conductance of control plants fell continuously from ~0.85 m s-1 to almost zero over a 9-day drying cycle. Plants sprayed with FA at the beginning of the cycle maintained a stomatal conductance of ~0.30 cm s-1 for the whole period. Spraying with FA resulted in a higher level of chlorophyll in the leaves and a greater uptake of 32P by the roots. When droughted at ear-development stage, grain yield was depressed by 30%. Spraying with FA increased the yield of droughted plants to 97% of the irrigated controls. Field trials in North China demonstrated that when FA was used to decrease the water stress or the stress imposed by hot, dry winds during ear development, grain yield increased by 7.3-18.0%.
Inheritance of aluminium tolerance in Phalaris aquatica L
Authors: Culvenor RA , Oram RN , Wood JT
Published: November 2004

The inheritance of aluminium tolerance in P. aquatica was investigated in solution culture, and correlations with other screening systems were determined. In the Israeli cultivar, Noy, the difference between the highly sensitive and moderately tolerant classes, which had been resolved in earlier experiments, can be largely explained by a two-gene hypothesis in which tolerance requires at least one dominant allele at each locus. Modifiers of these genes may also be involved. Assuming that the extensive continuous variation within the moderately tolerant class is polygenic, a quantitative inheritance study was conducted in a population of half-sib families in a diverse breeding population, the sensitive class being eliminated on performance in solution. Heritability estimates for relative root extension in solution ranged from 0.48 to 0.75, and estimated response to selection was high. However, heritability estimates for shoot growth of the same plants on a field site high in aluminium were low and non-significant (0.07-0.26). The highest estimate of genetic correlation between solution and field was not significant at 0.56. Variability in soil aluminium concentrations appeared to be a major cause of these low values. Prior screening of the population using a haematoxylin root-staining procedure gave a significant genetic correlation with solution responses (0.48). However, the technique requires further development for screening phalaris. In breeding for improved tolerance, the highly sensitive class could be eliminated by test crossing potential parents with homozygous sensitive plants. Several generations of selection could then be imposed, which, on the basis of genetic parameters estimated from solution screening, should yield a population appreciably more aluminium-tolerant than existing cultivars.
Mycotoxins in water-damaged and mouldy wheat from temporary bulk stores in Queensland
Authors: Blaney BJ
Published: November 2004

Temporary bulk stores are used by the Australian wheat industry to cope with peak wheat deliveries. Such stores are vulnerable to water damage if the plastic covering sheets are damaged, and extensive mould growth may then result. Samples of mouldy grain from stores in the main wheat-growing region of southern Queensland were assayed for aflatoxins B1, B2, G1, and G2, ochratoxin A and sterigmatocystin, but only aflatoxins B1 and B2 were detected. Of 152 mouldy samples from 12 temporary stores of the 1981 wheat crop, anatoxins were detected in 21 (range 0.002-0.060, mean 0.016 mg B1 kg-1). Aflatoxins were also present in 10 out of 13 samples from the single store of the smaller 1982 crop (range 0.003-0.500, mean 0.064 mg B1 kg-1). Aflatoxins were detected at trace levels (0.003-0.004 mg B1, kg-1) in 2 out of 70 samples of apparently clean, free-flowing grain from rhese same stores. Both the frequency of contamination and aflatoxins concentrations were low, indicating either that the inoculum of Aspergillus flavus was low or that conditions were unsuitable for aflatoxin production.
Assessment of drought resistance in pearl millet (Pennisetum americanum (L.) Leeke). II. Estimation of genotype response to stress
Authors: Bidinger FR , Mahalakshmi V , Rao GDP
Published: November 2004

The finding that the more than 50% of the variation in grain yield of pearl millet breeding lines in two different drought stress treatments could be attributed to variation in yield potential and time of flowering was used to develop a drought-response index (DRI) based on the residual variation in grain yield, adjusted for experimental error. DRI was positively correlated to measured yield in the drought treatments, and independent of both yield potential and time to flowering. DRI in both midseason and terminal stress treatments was unrelated to yield component structure in the irrigated control treatment, indicating that selection for plant type under non-stressed conditions will not influence drought response. DRI was correlated to both grain number per panicle, and grain yield per panicle in both stress treatments, suggesting differential ability to maintain normal grain number, and/or that grain yield per panicle was an important factor in response to stress. Maintenance of panicle number did not seem to be important for maintenance of yield under drought stress. The correlation of DRI and individual panicle yield was of sufficient magnitude for the latter to serve as a selection index in terminal stress. The use of a DRI as a component of breeding for better adaptation to stress is discussed.
Prediction of wheat yield loss due to competition by wild oats (Avena spp.)
Authors: Martin RJ , Cullis BR , McNamara DW
Published: November 2004

Field experiments were conducted to determine the effect of varying the density of wheat (cv. Gamut) and wild oats (Avena fatua and A. sterilis ssp. ludoviciana) on the grain yield of wheat. Wheat grain yields were reduced by wild oats through the reduction in number of tillers, and this competitive effect could be reduced by increasing the density of wheat. Increasing wheat plant density beyond the weed-free optimum was found to be unsatisfactory for wild oat control. The best model to describe the data comprised a parabolic wheat yield-density component and a hyperbolic yield loss component. Parameters in the yield-density component were calibrated using 36 data sets to account for variation in sowing date and available soil water. The parabolic model best described the effect of limiting soil water on the wheat yield-density relationship. The yield loss component, which included weed and crop density as variables, indicated that wheat and wild oats behaved as near-equal competitors.The predictive ability of the yield loss model varied when tested on several independent data sets collected from commercial wheat crops. This variation was caused by changes in the relative competitive ability of the crop and weed which resulted in significant variation in values of the yield loss parameters. Further refinement and generalization of the model will be possible if the yield loss parameters can be related to genetic and environmental variables.
The effect of boron supply on the growth and seed production of subterranean clover (Trifolium subterraneum L.)
Authors: Dear BS , Lipsett J
Published: November 2004

There has been little research on the boron (B) status of subterranean clover, despite strong indications of deficiency of B in southern Australia where clover decline has been reported. This paper describes glasshouse experiments to vary the level of B supply to clover grown on soils low in B. On a soil farmed in a cereal clover rotation, herbage yields of clover increased by 25% with applied B, but seed yields, negligible without B, increased 21-fold. On two other acid soils, from pastures, there were also large responses to B in seed yield (1.5- and 5.1-fold respectively); liming increased the responses (8- and 55.2-fold). However, herbage production was less responsive to B (25% and 1.7-fold with liming); on the unlimed soils, application of B depressed yield (- 1 and -21%). This is attributed to there being enough B to sustain herbage growth, but inadequate for seed formation. These results show that herbage yield, conventionally employed in the past, is not a satisfactory index of B status for total performance in subterranean clover. The response to B in seed yield was associated with increases in: numbers of seed set (75% to 22.6-fold, depending on the particular combination of soil and liming); size of seed (10% to 1.2-fold); proportion of buried seed (20%-70%). It is suggested that these favour establishment and persistence of clover and that clover decline may well involve deficiency of B. It was shown that concentration of B in the plant does not necessarily relate predictably to yield of herbage and that reduction in seed yield may not be heralded by foliar symptoms, since seed requirement exceeds that of herbage.
Corrigendum - Predicting phenological development for Australian wheats
Authors: Perry MW , Siddique KHM , Wallace JF
Published: November 2004

Dates of ear initation and anthesis were recorded for 16 wheat cultivars at a wide range of sowing dates in four field experiments conducted over four years.In general for the majority of cultivars number of days from sowing to ear initiation increased as sowing was delayed through May and then declined with sowings after June. The effects of sowing date and cultivar on anthesis were similar to those observed for ear initiation. Maximum time to anthesis was observed from sowings in early May.A linear regression model relating rate of development to mean temperature and photoperiod accounted for 47-98% of the variation in rate of development from sowing to ear initiation and from 68 to 98% of the variation from ear initiation to anthesis. A five-parameter non-linear model was also tested but was not superior. Observations in a single year were sufficient to characterize a cultivar provided the range of mean temperature and photoperiod was large.Comparison with data from other field sites of ear initiation and anthesis showed that the regression equations gave a good fit to the occurrence of these events when used in the incremental sense, that is, by summing increments of development rate calculated from daily temperature and photoperiod.The prediction model is discussed in relation to its application in simulation models of crop growth, analysis of cultivar adaptation to environments and in day-to-day crop management.
Production of the mycotoxins zearalenone, 4-deoxynivalenol and nivalenol by isolates of Fusarium graminearum groups 1 and 2 from cereals in Queensland
Authors: Blaney BJ , Dodman RL
Published: November 2004

The production of the mycotoxins zearalenone (ZEA), 4-deoxynivalenol (DON) and nivalenol (NIV) by isolates of Fusarium graminearum from different crops and regions in Queensland was examined in maize meal incubated for 28 days at 28�C. Sixteen isolates of F. grarninearum Group 1 from wheat and barley stalks and a wheat seed in southern Queensland produced ZEA (range 208-2367, median 833 mg kg-1) and DON (range 3-28, median 15 mg Kg-1). One Group 1 isolate from a wheat stalk was unlike these 16, producing 2 mg ZEA kg-1 and 168 mg DON kg-1. Fifteen isolates of F. graminearum Group 2 from wheat seeds and spikelets, and sorghum and maize stalks in southern Queensland produced ZEA (range 25-2280, median 629 mg kg-1) and DON (range 11-904, median 200 mg kg-1. Three isolates from wheat seeds produced ZEA (range 5-41, median 15 mg kg-1) and NIV (range 10-75, median 40 mg kg-1). All 23 isolates of F. graminearum Group 2 from maize seeds and stalks in northern Queensland produced ZEA (range 3-228, median 40 mg kg-1) and NIV (range 8-270, median 26 mg kg-1). Group 1 isolates tended to produce more ZEA and less DON than Group 2 DON-producers, but there was a degree of overlap. Group 2 NIV-producers generally produced less ZEA than Group 1 and Group 2 DON-producers. No relationship between either climate or host and mycotoxin production was detected.
Oestrogenic damage and reduced fertility in ewe flocks in south Western Australia
Authors: Adams NR , Sanders MR , Ritar AJ
Published: November 2004

Prolonged exposure to oestrogen causes transsexual redifferentiation in the ewe, which can be assessed experimentally by measuring the cross-sectional area of lamina propria (lp) tissue lying underneath the cervical folds in the mid-cervix. The extent of transsexual redifferentiation caused by prolonged exposure to clover oestrogens was measured in ewes from 13 farms in Western Australia. Groups of 90-157 mature ewes were mated under normal farming husbandry, and consigned to the abattoirs 6-8 weeks later. Histological sections were prepared from the mid cervix of 37-80 ewes from each flock. The area of lp was increased in ewes from the three farms with a history of infertility due to oestrogenic clover, when compared with ewes from the four farms in non-clover areas. Overall, the mean area of lp in ewes from the 13 farms was correlated (r = 0.81, P < 0.01) with the proportion of non-pregnant ewes, but less so with the potential lambing rate as judged by the number of foetuses/100 ewes (r = -0.51, N.S.). This contrast came about because flocks affected by oestrogen-induced transdifferentiation also tended to have higher ovulation rates; a regression including both the ovulation rate and area of lp accounted for 89010 of the variation between flocks in potential lambing rate. It is concluded that clover oestrogens are an important cause of the relatively high proportion of ewes which fail to lamb in Western Australia.
Efficiency of index selection for dairy cattle using economic weights for major milk constituents
Authors: Beard KT
Published: November 2004

A breeding objective (aggregate genotype) for dairy cattle based on returns, net of feed costs, from yield of fat, protein and carrier (the non-fat, non-protein component of the milk) was developed. Returns were estimated using a forecast of the future Australian dairy market structure, and feed costs were estimated from the metabolizable energy required to produce each of three milk components.The effects of erors in forecasting future conditions on economic weights and efficiency of index selection of sires were examined.Economic weights varied widely when subject to errors in the price of milk components within markets, errors in the export price for milk and errors in feed cost.Selection based on an optimal index of sire expected breeding values for fat, protein and milk was sensitive to low export market prices, high feed costs, high protein price and high carrier price. This index was quite insensitive to variation in prices and costs opposite in sign to those above, to variation in milk prices on the domestic markets, and to variation in the size of quotas on domestic markets.