bluuebunny/crossref_metadata_2025 huggingface dataset:
Explosion of a railcar containing toluene diisocyanate waste
Authors: Ogle Russell A. , Carpenter Andrew R. , Morrison Delmar R.
Published: November 2004

A railcar containing toluene diisocyanate (TDI) waste exploded during the unloading process at a hazardous waste‐treatment and disposal facility. The TDI waste material was to be used as a fuel at the RCRA‐permitted facility. Because of the viscous, almost solidlike consistency of the waste, the railcar was steam‐heated to facilitate unloading. The attempted unloading took place over a 5‐day period. The railcar was heated on two separate occasions and unloading was unsuccessfully attempted three times. The decision was made to reject the railcar shipment, but it remained at the unloading station. Approximately 2 days after the last heating cycle, the railcar exploded.

This paper summarizes the accident investigation, with particular emphasis on the assessment of the reactivity hazards and self‐heating potential of the railcar contents. Under the circumstances of this accident, TDI should not undergo significant thermal decomposition. The evidence suggested the explosion was caused by the thermal decomposition of a contaminant that was not normally present in the TDI waste. © 2004 American Institute of Chemical Engineers Process Saf Prog, 2004
Expectation‐based, inference‐based, and bottom‐up software comprehension
Authors: O'Brien Michael P. , Buckley Jim , Shaft Teresa M.
Published: November 2004

The software comprehension process has been conceptualized as being either ‘top‐down’ or ‘bottom‐up’ in nature. We formally distinguish between two comprehension processes that have previously been grouped together as ‘top‐down’. The first is ‘expectation‐based’ comprehension, where the programmer has pre‐generated expectations of the code's meaning. The second is ‘inference‐based’ comprehension, where the programmer derives meaning from clichéd implementations in the code.

We identify the distinguishing features of the two variants, and use these characteristics as the basis for an empirical study. This study establishes the existence of the above‐mentioned processes, in conjunction with ‘bottom‐up’ comprehension. It also illustrates the relationship between these processes and programmers' application domain familiarity. Copyright © 2004 John Wiley & Sons, Ltd.
Enhancing the first enzymatic step in the histidine biosynthesis pathway increases the free histidine pool and nickel tolerance in Arabidopsis thaliana
Authors: Wycisk Katharina , Kim Eugene J. , Schroeder Julian I. , Krämer Ute
Published: November 2004

Naturally selected nickel (Ni) tolerance in Alyssum lesbiacum has been proposed to involve constitutively high levels of endogenous free histidine. Transgenic Arabidopsis thaliana expressing a Salmonella typhimurium ATP phosphoribosyl transferase enzyme (StHisG) resistant to feedback inhibition by histidine contained approximately 2‐fold higher histidine concentrations than wild type plants. Under exposure to a toxic Ni concentration, biomass production in StHisG expressing lines was between 14‐ and 40‐fold higher than in wild‐type plants. This suggested that enhancing the first step in the histidine biosynthesis pathway is sufficient to increase the endogenous free histidine pool and Ni tolerance in A. thaliana.
Volatile anesthetic modulation of oligomerization equilibria in a hexameric model peptide
Authors: Ghirlanda Giovanna , Hilcove Simon A. , Pidikiti Ravindernath , Johansson Jonas S. , Lear James D. , DeGrado William F. , Eckenhoff Roderic G.
Published: November 2004

To determine if occupancy of interfacial pockets in oligomeric proteins by volatile anesthetic molecules can allosterically regulate oligomerization equilibria, variants of a three‐helix bundle peptide able to form higher oligomers were studied with analytical ultracentrifugation, hydrogen exchange and modeling. Halothane shifted the oligomerization equilibria towards the oligomer only in a mutation predicted to create sufficient volume in the hexameric pocket. Other mutations at this residue, predicted to create a too small or too polar pocket, were unaffected by halothane. Inhaled anesthetic modulation of oligomerization interactions is a novel and potentially generalizable biophysical basis for some anesthetic actions.
Decreased cellular permeability to H2O2 protects Saccharomyces cerevisiae cells in stationary phase against oxidative stress
Authors: Sousa-Lopes A. , Antunes F. , Cyrne L. , Marinho H.S.
Published: November 2004

The higher resistance of stationary‐phase Saccharomyces cerevisiae to H2O2 when compared with exponential phase is well characterized, but the molecular mechanisms underlying it remain mostly unknown. By applying the steady‐state H2O2‐delivery model, we show that (a) cellular permeability to H2O2 is five times lower in stationary – than in exponential phase; (b) cell survival to H2O2 correlates with H2O2 cellular gradients for a variety of cells; and, (c) cells in stationary phase are predicted to be more susceptible to intracellular H2O2 than in exponential phase. In conclusion, limiting H2O2 diffusion into cells is a key protective mechanism against extracellular H2O2.
Specific interaction between S6K1 and CoA synthase: a potential link between the mTOR/S6K pathway, CoA biosynthesis and energy metabolism
Authors: Nemazanyy Ivan , Panasyuk Ganna , Zhyvoloup Alexander , Panayotou George , Gout Ivan T. , Filonenko Valeriy
Published: November 2004

Ribosomal protein S6 kinase (S6K) is a key regulator of cell size and growth. It is regulated via phosphoinositide 3‐kinases (PI3K) and the mammalian target of rapamycin (mTOR) signaling pathways. We demonstrate for the first time that CoA synthase associates specifically with S6K1. The association was observed between native and transiently overexpressed proteins in vivo, as well as by BIAcore analysis in vitro. The sites of interaction were mapped to the C‐terminal regions of both CoA synthase and S6K1. In vitro studies indicated that the interaction does not affect their enzymatic activities and that CoA synthase is not a substrate for S6 kinase. This study uncovers a potential link between mTor/S6K signaling pathway and energy metabolism through CoA and its thioester derivatives, but its physiological relevance should be further elucidated.
Identification and characterization of D8C, a novel domain present in liver‐specific LZP, uromodulin and glycoprotein 2, mutated in familial juvenile hyperuricaemic nephropathy
Authors: Yang Huirong , Wu Chaoqun , Zhao Shouyuan , Guo Jinhu
Published: November 2004

Present work reported a novel domain – D8C (domain with conserved eight cysteines in liver‐specific ZP domain‐containing protein, glycoprotein 2 (GP‐2) and uromodulin (UMOD)), present in liver‐specific LZP, UMOD, GP‐2 and some uncharacterized proteins, most of which are membrane proteins, extracellular proteins or nuclear membrane proteins. D8C contains eight well‐conserved cysteine residues, which were predicted to form four pairs of disulfide bridges. D8C is composed mainly of β‐strands. Mutation in the D8C at Cys217 in human UMOD is associated with familial juvenile hyperuricaemic nephropathy, which might be due to the disruption of the disulfide bridge. Identification of D8C would further the understandings of related proteins.
Catalytic site‐specific inhibition of the 20S proteasome by 4‐hydroxynonenal
Authors: Ferrington Deborah A. , Kapphahn Rebecca J.
Published: November 2004

The proteasome is responsible for most intracellular protein degradation and is essential for cell survival. Previous research has shown that the proteasome can be inhibited by a number of oxidants, including 4‐hydroxynonenal (HNE). The present study demonstrates that HNE rapidly inhibits the chymotrypsin‐like activity of the 20S proteasome purified from liver. Subunits containing HNE‐adducts were identified following 2D gel electrophoresis, Western immunoblotting, and analysis by MALDI‐TOF MS. At a time when only the chymotrypsin‐like activity was inhibited, the α6/C2 subunit was uniquely modified. These results provide important molecular details regarding the catalytic site‐specific inhibition of proteasome by HNE.
A novel first exon of the Patched1 gene is upregulated by Hedgehog signaling resulting in a protein with pathway inhibitory functions
Authors: Shimokawa Takashi , Rahnama Fahimeh , Zaphiropoulos Peter G.
Published: November 2004

Patched homolog 1 (PTCH1) is a key component of the Hedgehog (HH) signaling pathway with three alternative first exons, but only exon 1B transcription depending on HH activation. Here, we show that in both human and mouse a novel PTCH1 first exon (1C) is expressed. Exon 1C transcription is upregulated by HH signaling, but the resulting PTCH1‐1C protein has a lower capacity for pathway inhibition than PTCH1‐1B.
Potential distribution around sounding rockets in mesospheric layers with charged aerosol particles
Authors: Sternovsky Z. , Holzworth R. H. , Horányi M. , Robertson S.
Published: November 2004

It is shown that large potential variations can exist inside the wake of sounding rockets moving with supersonic velocity through the summertime mesopause region. The potential distribution is driven by charge separation induced by the shock wave of the rocket. The low conductivity conditions due to the attachment of free electrons to aerosol particles allow large electric fields, of the order of V/m, to be maintained. The numerical results from a simple model are consistent with recent electric field measurements carried out by the DROPPS‐1 sounding rocket.
Evolution of U‐Pb and Sm‐Nd systems in numerical models of mantle convection and plate tectonics
Authors: Xie Shunxing , Tackley Paul J.
Published: November 2004

The development of U‐Th‐Pb and Sm‐Nd isotopic signatures in a convecting mantle is studied using a numerical convection model with melting‐induced differentiation and tracking of major and trace elements. The models include secular cooling and the decay of heat‐producing elements, a rudimentary “self‐consistent” treatment of plate tectonics, and both olivine system and garnet‐pyroxene system phase transitions. The system self‐consistently evolves regions with a high μ(=U/Pb) (HIMU)‐like Pb signature and regions with low 143Nd/144Nd. However, the isotopic “age” determined from the slope in (207Pb/204Pb)–(206Pb/204Pb) space is much larger than observed. Several hypotheses are examined to explain this discrepancy. Sampling length scale has a minimal effect on age. The extent of crustal settling above the core‐mantle boundary makes some difference but not enough. More frequent remelting is a possible explanation but requires the rate of crustal production to have been much higher in the past. Not introducing HIMU into the mantle prior to 2.0–2.5 Gyr before present, because of a change in the surface oxidization environment or subduction zone processes, can account for the difference, but its effect on other isotope systems needs to be evaluated. Improved treatment of the stretching of heterogeneities, which reduces them to length scales at which they cease to be identifiable magma sources, greatly reduces the Pb‐Pb age. The mantle develops substantial chemical stratification from a homogeneous start, including stratification around 660 km caused by the two‐component phase transitions. A deep layer of subducted crust may provide storage for some of the “missing” heat‐producing elements. Magmatic heat transport is important in the first 2 Gyr of model time.
Decadal variability of northern northeast Brazil rainfall and its relation to tropical sea surface temperature and global sea level pressure anomalies
Authors: Kayano Mary Toshie , Andreoli Rita Valéria
Published: November 2004

Decadal (9–14 year) relations of the northern northeastern Brazil (NEB) rainfall to the sea surface temperature (SST) in the 60°N–30°S oceanic sector and to the global sea level pressure (SLP) anomalies are investigated for the 1871–1991 period. Indices are defined for the precipitation and for the SST anomalies in the tropical North Atlantic (TNA), in the tropical South Atlantic (TSA), and in the eastern equatorial Pacific (T‐TNA, T‐TSA, and T‐NINO indices, respectively). An index is also defined for the SLP anomalies in the North Atlantic Oscillation region (P‐NAO index). These indices and the SST and SLP anomaly time series are filtered for the decadal scale using the continuous wavelet transform. The filtered time series are then subjected to the correlation and partial correlation analyses. The results indicate that the decadal variations of the northern NEB rainfall might be independently linked to the Pacific Decadal Oscillation (PDO)/NAO/TNA decadal relations or to the SST decadal variations in the TSA. This is a new result not discussed before. The northern NEB rainfall linkage to the PDO/NAO/TNA relations is indicative that the relationship of the SLP variations in the NAO region and the NEB rainfall proposed in a work during the 1970s is part of the decadal climate variability that connects the PDO in the tropical Pacific to the NEB rainfall through the Northern Hemisphere extratropical atmosphere.
Tropical Pacific decadal variability and ENSO amplitude modulation in a CGCM
Authors: Yeh Sang‐Wook , Kirtman Ben P.
Published: November 2004

Connections between decadal changes in the tropical Pacific mean state and El Niño–Southern Oscillation (ENSO) decadal modulation are examined using three runs of a coupled general circulation model (CGCM). The differences between the three simulations, i.e., a standard coupled model (one AGCM is coupled to a single OGCM) and two interactive ensemble models (six or twelve AGCMs are coupled to a single OGCM), are confined to the amplitude of internal atmospheric variability. All three simulations have the same tropical Pacific basin scale SST mode that dominates the low‐frequency variability, which is identified by the first EOF mode. This low‐frequency mode is largely independent of the simulated ENSO and is neither a residual of the decadal ENSO modulation nor does it produce any low‐frequency modulation of ENSO. The analysis presented here suggests that this low‐frequency mode is stochastically driven by atmosphere noise. There are, however, low‐frequency changes in the tropical Pacific mean state that are connected to ENSO decadal modulation. The mean state associated with ENSO amplitude has different structures in the SST and wind stress anomalies than does the dominant tropical Pacific mean state identified by the first EOF. The tropical Pacific mean state that is unambiguously associated with ENSO decadal modulation, which is remarkably similar to the second EOF SST mode in two interactive ensemble models, but is difficult to detect in a standard coupled model simulation. These results argue that there is a component of ENSO variability that cannot be explained by a linear, damped and stochastically forced process.
Extraction of Martian valley networks from digital topography
Authors: Stepinski T. F. , Collier M. L.
Published: November 2004

We have developed a novel method for delineating valley networks on Mars. The valleys are inferred from digital topography by an autonomous computer algorithm as drainage networks, instead of being manually mapped from images. Individual drainage basins are precisely defined and reconstructed to restore flow continuity disrupted by craters. Drainage networks are extracted from their underlying basins using the contributing area threshold method. We demonstrate that such drainage networks coincide with mapped valley networks verifying that valley networks are indeed drainage systems. Our procedure is capable of delineating and analyzing valley networks with unparalleled speed and consistency. We have applied this method to 28 Noachian locations on Mars exhibiting prominent valley networks. All extracted networks have a planar morphology similar to that of terrestrial river networks. They are characterized by a drainage density of ∼0.1 km−1, low in comparison to the drainage density of terrestrial river networks. Slopes of “streams” in Martian valley networks decrease downstream at a slower rate than slopes of streams in terrestrial river networks. This analysis, based on a sizable data set of valley networks, reveals that although valley networks have some features pointing to their origin by precipitation‐fed runoff erosion, their quantitative characteristics suggest that precipitation intensity and/or longevity of past pluvial climate were inadequate to develop mature drainage basins on Mars.
A selective medium for determining the population of viable conidia of Cochliobolus sativus in soil
Authors: Dodman RL , Reinke JR
Published: November 2004

A selective medium containing three antibiotics, three fungicides, and rose Bengal has been developed for the determination of populations of viable conidia of Cochliobolus sativus in soils by the dilution plate procedure. With this medium, complete recovery of added conidia was achieved; the level of recovery was not significantly different (P > 0.05) when conidia were present in two different soils. The medium should be useful for ecological studies of C. sativus.
The regulatory effect of pine sawdust (Pinus pinaster) on the intake of wheat grain by sheep
Authors: Hunter RA , Purser DB
Published: November 2004

In two experiments, pelleted diets consisting of different proportions of wheat grain and Pinus pinaster sawdust were offered ad libitum to sheep. The ratios of wheat to sawdust fed in the first experiment were 100: 0, 85 : 15,70: 30, 60: 40 and 50: 50. Organic matter (OM) intakes (and digestible organic matter intakes (DOMI)) were 436(382), 520(423), 244(146), 293(117) and 165(88) g/day respectively. In the second experiment the ratios of wheat to sawdust were 100:0, 80:20 and 65: 35. These diets were fed with and without the addition of formaldehyde-treated casein (FTC). Intakes (OM (DOMI)) of the diet without FTC were 499(442), 611(431) and 239(134) g/day respectively, and of the diets with FTC 500(431), 406(320) and 320(199) g/day respectively. Addition of FTC had no significant effect on intake. Sawdust had a major regulating effect on the intake of wheat. The mean sawdust intake of the eight different diets was 94 g/day (range 73-122 g/day). Since sheep would eat only 94 g/day of sawdust the intake of wheat depended on the ratio of wheat to sawdust, i.e. the quantity of wheat that was associated with 94 g sawdust.
Body composition of live cattle and its prediction from fasted liveweight, tritiated water space and age
Authors: Bird PR , Flinn PC , Cayley JWD , Watson MJ
Published: November 2004

The body composition of 23 Hereford steers was related to their liveweight after a 24 h fast (W), total body water (TBW), tritiated water space (T) and age in months (A) by using allometric or linear regression models. Fifteen steers, of similar initial age, were taken at intervals from a grazing experiment having a wide range of stocking rates. These steers were 15-22 months of age and 189-461 kg W at slaughter. Six younger and two older steers were also used to expand the range to 3-33 months and 90-517 kg. The steers were taken from pasture 3 h after sunrise and deprived of feed and water thereafter. After 4 h, tritiated water was given intramuscularly and 20 h later blood was collected and the animals were weighed and slaughtered. Models having the least residual standard deviation (r.s.d.) and the predictors which contributed significantly in the stepwise regression analysis (P i 0.05) are given for each range of W. T greatly improved the estimation of fat and slightly improved the prediction of protein. A only slightly improved the prediction of TBW and fat. Equations applicable to the narrow range of W were: total body water (kg) =
Leaf acid phosphatase activity and the phosphorus status of field-grown wheat
Authors: McLachlan KD
Published: November 2004

Acid phosphatase activity (E.C.3.1.3.4.1) measured in leaf extracts of field-grown wheat was used to indicate the phosphorus status of the plants. Plants responded to phosphorus applications at both experimental sites, and were sampled on a number of occasions during crop development. Significant (P < 0.001) negative correlations between phosphatase activity and phosphorus status, either phosphorus content or phosphorus concentration, were obtained during the early stages of development (r > - 0.87, R2 > 79 %, and r > - 0.87, R2 > 86 % respectively). The activity at those times was also correlated significantly with final grain yield (r > 0.79, R2 > 73%, P < 0.001). The relations were less useful in the later harvests. The evidence indicates reasons for this, and suggests that even at those harvests leaf phosphatase activity continued to be a very sensitive measure of plant phosphorus status. This sensitivity should make it a useful research tool, but as a field measure, renders the assay subject to interactions with the biological environment that affect growth and yield. Under these circumstances, no single 'critical value' for activity relative to plant performance could be derived to suit all situations. Nevertheless, there seems to be scope for determining local phosphatase standards for particular crops and regional environments which would make the assay a useful diagnostic tool. The assay is simple, direct and rapid, and has the advantage, even under poor seasonal conditions, that the relation with grain yield is best for young plants, the stage at which fertilizer applications have the greatest benefit on final yield.
Response of four grain legumes to water stress in south-eastern Queensland. III. Dry matter production, yield and water use efficiency
Authors: Lawn RJ
Published: November 2004

Dry matter production, yield and water use efficiency of soybean (Glycine max), black gram (Vigna mungo), green gram (V. radiata) and cowpea (V. unguiculata) under irrigated, rain-fed fallowed and rain-fed double-cropped culture were evaluated at Dalby in south-east Queensland. Differential species responses to cultural treatments were related to strategies of growth and water use in response to water stress. The major effect of differences between strategies related to differences in the short term rate of soil water use, which together with the seasonal pattern of water availability influenced both the total, and seasonal pattern of water use. Regardless of strategy adopted, dry matter production was primarily a function of water use. However, seed yield and water use efficiency for seed yield depended on the seasonal pattern of water use. The relative agronomic success of the various strategies therefore depended on the seasonal profiles of water availability. Some implications of the differences in stress response strategy for adaptation of these species to agricultural environments are discussed.
The effect of growth temperature on dry weight and carbohydrate content of onion (Allium cepa L. cv. Creamgold) bulbs
Authors: Steer BT
Published: November 2004

Onion bulbs (Allium cepa L. cv. Creamgold), grown in a phytotron from seed, had a dry weight as percentage of fresh weight that decreased as growth temperatures increased from 22/16 to 33/28�C day/night. There were no significant differences between growth temperatures in the fructose, sucrose or fructan content and, although glucose content was higher at high temperatures, there was no correlation of total carbohydrate content with growth temperature. The sum of fructose, glucose and sucrose per unit tissue water was constant between temperatures, suggesting that the mono- and disaccharide content may control the bulb water content. These results, from controlled-environment tests, predict that in the field the best yield of dry weight as a percentage of fresh weight will be obtained at low growth temperatures.
Effects of shade on some factors influencing nutritive quality of green panic and Siratro pastures
Authors: Wilson JR , Wong CC
Published: November 2004

The effect of illumination at 100, 60 and 40% sunlight over 4 months on herbage quality was studied in the legume, Siratro, and the grass, green panic, grown in small plots in the field in pure and 50 : 50 mixture swards, defoliated every 4 (D4) or 8 (D8) weeks. Laminae and stems of defined ages were harvested periodically from the D8 treatment, and after 8 and 16 weeks the D4 and D8 canopies were sampled in 10-cm strata for analysis of dry matter digestibility (DMD). Shading to 60 and 40% sunlight decreased the DMD of the green panic and the mixed swards by up to 10-12 percentage units in the D8 treatment. The shade effect on DMD was smaller in the D4 treatment. Shading increased leaf bulk density in the upper strata of the grass and mixed swards. The shade effect on sward DMD was due to a decrease in DMD of lamina and stem of green panic and, in the lower canopy, also to a decrease in leaf : stem ratio of the grass. The lower DMD of green panic was associated with lower total soluble carbohydrate and higher lignin in the shaded tissues. The concurrent decrease in cell wall content of green panic under shade (as a balance to higher crude protein) indicates that shade must have greatly reduced the digestibility of the cell wall material. The chemical composition and DMD of Siratro was largely unaffected by shade.
Infectivity of vesicular arbuscular mycorrhizal fungi in agricultural soils
Authors: Abbott LK , Robson AD
Published: November 2004

The development of vesicular arbuscular (VA) mycorrhizas was followed for subterranean clover grown in 20 field soils in a glasshouse experiment. The aims of the study were: to understand the way in which mycorrhizas develop in field soils; to identify those factors which could be used to predict field sites suitable for inoculation with VA mycorrhizal fungi. In each soil, the amount and rate of mycorrhiza formation were estimated for species of each genus represented. The data were examined in relation to differences among soils in numbers of spores of VA mycorrhizal fungi and in soil properties. A poor correlation between total spore numbers and the total amount and rate of infection formed was attributed to two factors. First, infection by fine endophyte (a fungus which does not form large spores that can be counted) was ubiquitous, but the amount of mycorrhizas formed by this fungus varied greatly. Second, species of fungi differed in their rates of infection. In general, there was an association between spore numbers and infection development for individual fungal species. The development of mycorrhizas in any soil fell into one of three categories: I, rapid and extensive; II, extensive but with a lag phase; III, slow and limited in extent. The species of fungi in soils from each category were similar. Category I included the soils which were most deficient in phosphorus for plant growth. However, from measurements of soil properties alone, it is not possible to predict those soils which are suitable for the introduction of inoculant VA mycorrhizal fungi.
The inheritance of seed resistance to Callosobruchus maculatus F. in cowpea (Vigna unguiculata L. Walp.). II. Analyses of percentage emergence and emergence periods of bruchids in F4 seed generation of two reciprocal crosses
Authors: Redden R
Published: November 2004

Seed from F3 generation plants of two reciprocal crosses were evaluated for bruchid resistance, over 28 F3 families of four plants each plus an additional five plants each in 10-11 families. The variables, percentage adult emergence for a specified period and mean time to emergence, agreed with respect to describing segregation in the resistant, intermediate and susceptible categories. Resistance was expressed as a recessive character. No differences between families from reciprocal crosses were detected. There was evidence for digenic control of resistance in one cross and for monogenic control in the other, in conjunction with one, or more, modifier or minor gene loci. There was general agreement between the results for the F3 generation study and a previous study on the F2 generation.
The genetic evaluation of bruchid resistance in seed of cowpea
Authors: Redden RJ , McGuire J
Published: November 2004

Seed resistance of cowpea (Vigna unguiculata L. Walp.) to bruchids at the F3 plant generation was assessed by various methods. The most discriminating variable for measurement of seed resistance was mean emergence day, followed by percentage of adult emergence up to an optimum time, then in descending order, percentage of undamaged seed, mean number of holes per seed and percentage loss in seed weight. The simplest reliable variable to use for assessment of resistance to bruchids was the percentage of undamaged seed with zero emergence holes. However, greater control and manipulation of egg laying on seeds would be required to obtain uniform infestation. Three (or less) eggs per seed is suggested as acceptable. Care, particularly on the uniformity of eggs laid, is necessary when using percentage seed weight loss as an index of resistance. The other variables are laborious to estimate. In general, seed weight, number of eggs per seed, seed testa texture and number of seeds per sample did not appear to influence estimates of resistance, with the exception of seed weight loss. The natural rate of increase of bruchids, which is a critical variable for measurement of resistance, was very difficult to estimate with consistency.
Copper oxide particles for grazing sheep
Authors: Langlands JP , Bowles JE , Donald GE , Smith AJ , Paull DR , Holmes PR
Published: November 2004

In a series of experiments aimed at evaluating copper oxide as a supplement, grazing sheep were dosed with varying quantities of copper oxide particles up to 64 g, and the toxicity, the rate of particle excretion, and copper storage in the liver and other tissues were recorded. The toxicities (LD50) of copper oxide particles were 1.17 and 1.80 g/kg liveweight for two groups of grazing adult fine-wool Merino sheep. Death usually occurred 88-96 days after the oral administration of the particles; mean hepatic copper concentrations of sheep dying from copper toxicity were 4122-4308 mg/kg DM. The rate of faecal copper excretion of copper-supplemented sheep, expressed as a percentage of the dose, was less when 50 g of particles were given than when the dose was 5 or 10 g, but excretion patterns were variable. The quantity of hepatic copper stored per g of copper oxide given declined as the dose increased from 0 to 32 g, but increased again at higher doses. Hepatic copper concentration reached a maximum 2-3 months after dosing and the rate of decline was positively related to dose rate; thus, large doses of copper are unlikely to extend the period of elevated copper status. Large doses also increased whole blood copper concentrations and elevated plasma aspartate transaminase activities; this was taken to indicate copper poisoning. Tissue copper concentrations from sheep given up to 64 g particles are reported; liver was the most sensitive to copper treatment. Copper contents of the lung and kidney also responded to copper therapy, but carcass components such as leg, shoulder and muscle did not. Weaned lambs given 2 g of particles (c. 0.13 g/kg liveweight) grew significantly faster than unsupplemented lambs. This dose rate was approximately one-seventh of that predicted to cause 5% mortality, and it is concluded that, at appropriate dose rates, this method of supplementation did not increase mortality or cause excessive increases in tissue copper concentrations, and could increase growth rate.
Utilization of urea and molasses supplements by sheep grazing oat stubble
Authors: Coombe JB , Mulholland JG
Published: November 2004

Mature crossbred wethers, grazed for 11 weeks on oat stubble at a stocking rate of 20 sheep ha-1, were unsupplemented or offered supplements of a urea-mineral block, a molasses lick or a urea-molasses lick. Following rain in the fourth week, half of the area was sprayed with desiccant herbicide to establish weed-free stubbles. The stubble initially yielded c. 2600 kg DM ha-1 of dead crop residues plus 900 kg DM ha-1 of fallen grain; after 11 weeks this had fallen to c. 1400 kg DM ha-1 of dead crop residues. Initially the sheep selected diets of 0.03-0.22 grain and 0.78-0.97 dead herbage and, during this time, urea-supplemented sheep selected diets lower in grain and nitrogen (N) content than those selected by unsupplemented sheep. On weedy stubbles, where green herbage yielded more than 100 kg DM ha-1, sheep selected a diet containing c. 0.78 green herbage (N content 2.6%), ate more digestible organic matter (DOM) and gained more weight than those on weed-free stubbles, where the diets consisted of 0.98 dead crop residues (N content 1.1 %). All sheep ate some of the urea-mineral blocks throughout, but 100% acceptance of the licks only occurred by the 6th week. Mean intakes reached desired levels (10 g urea and/or 50 g molasses sheep-1 day-1) thereafter, but individual intakes varied widely on all supplements, with the coefficient of variation generally > 50%. In most periods, supplementation had only small effects on the intake of DOM. During the first 4 weeks, sheep lost weight except those offered the urea-mineral blocks. Over the whole experiment, urea-supplemented sheep lost less weight than unsupplemented sheep, but this was mainly due to higher weight gains on the weedy plots. Mean concentrations of rumen volatile fatty acids (VFA) were < 80 mmol l-1 throughout, and fell to <40 mmol l-1 on the weed-free plots in the latter stages of the experiment. Mean rumen ammonia levels, which were < 100 mg N l-1 in unsupplemented sheep, were generally increased by urea supplements, and by grazing weedy stubbles. Responses to supplementation are discussed in terms of the quality of the available plant material, the diet selected, the levels of rumen metabolites and the intake of supplements.
The influence of nutrition on the response of wheat to above-optimal temperature
Authors: Dawson IA , Wardlaw IF
Published: November 2004

Wheat plants (Triticum aestivum L. cv. Gabo) were grown at two temperatures (18/13 and 24/19�C, Day/night), either with full nutrient availability or deprived of nutrients after floral initiation or after anthesis, in order to identify possible interactions between nutrient availability and response to a temperature higher than the optimum for grain dry weight accumulation. Nutrient deprivation reduced levels of nitrogen, potassium and calcium in the vegetative organs of the plant at anthesis and maturity, and levels of nitrogen and calcium, but not potassium, in the grain. Differences in the distribution of nitrogen, potassium and calcium can be explained on the basis of their phloem mobility. An interaction was observed between nutrition and temperature in the time from seedling emergence to anthesis, the number of tillers at anthesis and the number of heads per plant at maturity. Within the main culm ear, high temperature and low nutrition reduced grain number. High temperature, but not low nutrition, reduced individual grain weights. However, there were no interactions between nutrition and temperature in regulating these responses. Therefore, although nutrition may be an important factor when considering the effect of temperature on tillering, there is no evidence from this study that nutritional status will mask the effects of temperature on the later stages of ear and grain development.
Yield and quality interrelationships amongst random F3 lines and their implications for wheat breeding
Authors: O'Brien L , Ronalds JA
Published: November 2004

The relationship between grain yield and grain quality was studied amongst sets of random Fj lines from seven wheat crosses. The quality measures used included grain hardness, flour yield, flour protein content, farinograph and extensograph properties, and small-scale empirical measures such as Zeleny and sodium dodecyl sulfate sedimentation volume, residue protein content, and Pelshenke fermentation time. A significant negative correlation was found between grain yield and flour protein content. Thus selection for either characteristic would be to the detriment of the other. However, grain yield was not significantly correlated with the other quality measures, indicating that high-yielding, good-quality wheats could be obtained from the population. Most of the small-scale tests were correlated with farinograph and extensograph properties, but the correlation coefficients were not as high as those obtained with varieties or advanced breeding lines. The relationships were not dependent on differences in flour yield, grain hardness or flour protein content, thereby simplifying their application to breeding programs. Concurrent breeding for higher grain yield and improved functional quality would appear feasible. However, flour protein content would, at best, be maintained at current levels as yield increased.
Effect of breed of dam, type of birth and sex of lamb on efficiency of conversion of food to lamb and wool in Merino, Poll Dorset × Merino and Border Leicester × Merino ewes
Authors: Kleemann DO , Dolling CHS , Ponzoni RW
Published: November 2004

The effects of breed of dam (South Australian Merino (M), Border Leicester x Merino (BL x M) and Poll Dorset x Merino (PD x M)), type of birth (single and twins) and sex of lamb (wether and ewe) on the efficiency of the ewe (organic matter intake per unit (liveweight)0.75 and clean wool weight per unit intake) and of the ewe-lamb(s)) unit (liveweight and carcass weight per unit intake) were examined in two pen experiments (PE1, PE2) and a grazing experiment (GE). Each single-born lamb in PE1 and PE2 was slaughtered at weights =32 and =35 kg, respectively, and twin-born lambs when their combined weight doubled that of singles. In GE all lambs were slaughtered on the same day at 35.5 kg mean liveweight. Ewes rearing twins ate 19% more (P < 0.05) organic matter per unit (liveweight)0.75 during lactation than those rearing singles, the other effects of breed and sex were not significant during either late pregnancy or lactation. BL x M ewes grew 32% less (P < 0.001) clean wool per unit intake than did M ewes in PE, whereas the breed difference in GE was not significant, PD x M ewes grew 39% less wool than M ewes in GE (P < 0.001). Ewes rearing twins were 23% less efficient in converting food to wool than those rearing singles in PE, (P < 0.01), the corresponding difference in GE was not significant. There were no significant differences between breeds of dam for efficiency of the ewe-lamb unit when lambs were compared at the same age. However, when lambs were grown to the same liveweight the M ewe-lamb unit produced 14% (P < 0.001) and 8% (P < 0.05) more liveweight and carcass weight per unit intake than the BL x M in PE,. These results include adjustment for the effects of type of birth and sex. In all experiments ewes with twin lambs were about 45-55% and 35-45% more efficient than those with singles on a liveweight and carcass weight basis, respectively (P < 0.001), the effects were independent of whether the lambs were at the same age or the same liveweight. We conclude that efficiency of conversion of food to carcass weight on a flock basis will be largely dependent on variation in reproduction rate and to a lesser extent on breed of dam, and on breed of dam only when lambs are slaughtered at the same liveweight. In contrast, the effects of breed of dam on efficiency of food conversion to wool fibre were large.
Root characteristics of some temperate legume species and varieties on deep, free-draining entisols
Authors: Hamblin AP , Hamblin J
Published: November 2004

We report experiments comparing several legumes with the aim of distinguishing genotypic from environmental differences in those root parameters which influence water use and nutrition. Temperate crop and pasture legumes were grown on three xeric psamment soils at latitude 29�S. in Western Australia to evaluate the relative root characteristics of different species. Sites had 428, 298 and 155 mm rainfall in the (winter) growing season. Maximum root depth was significantly different (P < 0.001) between genotypes, but non-significant between sites. Genetic control for maximum root depth is thus implied. This has significance for water use and plant production of these low water-storage sandy soils. Lupinus spp. extended their roots to an average 190 cm, Pisum sativum L. to only 65 cm, Triticum aestivum L. to 113 cm. The pasture species ranged from Vicia benghalensis L. (75 cm) and Trifolium spp. (69 cm) to Medicago spp. which averaged 92 cm. Lupins and wheat had less than 50% of their total root length (cm-1) in the top 20 cm, whereas other species all had over 70% of roots in that layer. Pasture legumes with high root density in that layer tend to dry sandy topsoils frequently, reducing nutrient availability and hence vegetative growth. Root density averaged only 0.045 for lupins, compared with 1.0 cm-2 for clovers. All total root lengths were low at maturity, compared with more favorable environments. Nevertheless, they were calculated to be adequate for water and mobile nutrient extraction from these sandy soils.
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.
Field evaluation of 15N techniques for estimating nitrogen fixation in legume-grass associations
Authors: Ledgard SF , Simpson JR , Freney JR , Bergersen FJ
Published: November 2004

Two techniques were used to estimate the percentage (P) of legume nitrogen fixed from atmospheric N, by subterranean clover or lucerne grown in association with either annual ryegrass or phalaris. With the 15N-enrichment technique, estimates of P for both legumes were higher when they were grown with ryegrass than with phalaris, and were lower for clover than for lucerne. The other technique, involving differences in the natural abundance of 15N, gave P values similar to those obtained by the 15N-enrichment technique, except where clover was grown with phalaris. Within 15N-enriched plots, when weed species were also used as reference plants, P was higher than when either grass species was used as the reference plant. Some aspects of the 15N-enrichment technique were examined further in the subterranean clover-annual ryegrass association. Differences in the timing and method of application of K15NO3, had no lasting effect on the estimate of P for clover. However, there was an initial increase in the P value where the K15NO3 was washed into the soil with 10 mm of water instead of 2 mm. There was no detectable nitrogenase activity associated directly with ryegrass and no fixed N2 was transferred from clover to ryegrass during the 36-day measurement period, indicating that the soil (or soil plus added 15NO-3) was the sole nitrogen source for ryegrass.
Effects of water rinses after calcium chloride dips, with and without additives, on the control of bitter pit of apples
Authors: Scott KJ , O'Loughlin J , England B , Roberts EA
Published: November 2004

Studies on the control of bitter pit in apples after harvest were conducted during two seasons in Tasmania and New Zealand. The cultivars, Cox's Orange Pippin, Sturmer Pippin, Golden Delicious, Delicious and Cleopatra, which are susceptible to bitter pit on overseas markets, were examined. Bitter pit was reduced and calcium content of the fruit increased, by dipping the fruit in calcium chloride solutions (1-3% w/v). The addition of diphenylamine or the non-ionic wetting agent, Agral 60 (ICI Australia), had little effect on the control of bitter pit or on the calcium content of the treated fruit. Rinsing in water even 1 or 2 days after dipping did not significantly increase the incidence of bitter pit or lower the calcium content of the fruit. There was no difference in the incidence of bitter pit between fruit stored at ambient temperature (15-20�C) or at 3-5�C during the interval between dipping and rinsing. Dipping apples in calcium chloride followed, after 1 or more days, by a water rinse may be suitable commercially for reducing bitter pit in a number of cultivars.
Fungi associated with bunch rot of grapes in the Hunter Valley
Authors: Nair NG
Published: November 2004

Botrytis cinerea was isolated from apparently healthy and surface-sterilized grape Vitis vinifera L. flowers and berries. It appears that style and stigma could be the major sites of infection in Shiraz cultivar. Fungicide (benomyl) spray at bud burst and at 75% flowering lowered the incidence of B. cinerea latent infection of flowers. It is pointed out that latent infection of flowers can, under favourable conditions, lead to the development of relatively high level of inoculum and consequently high risk of berry rot. The demonstration of latent infection by B. cinerea could have important implications in the development of a management system for bunch rot control in the Hunter Valley. B. cinerea, Alternaria alternata, Rhizopus sp., Gonatobotrys simplex, Aspergillus niger, Cladosporium cladosporioides, Fusarium sporotrichioides, Epicoccum nigrum and Bipolaris bicolor were isolated frequently from flowers and berries. There appears to be diversity in the fungal flora associated with flowers and berries in Shiraz. Artificial inoculation of mature berries with A. alternata, Rhizopus sp. and A. niger resulted in some degree of rotting. It appears, therefore, that these fungi associated with berries may play a part in the development of berry rot.
Mycoplasma-like organisms as causal agents of potato purple top wilt in Queensland
Authors: Harding RM , Teakle DS
Published: November 2004

The eggplant little-leaf agent was graft transmitted to tomato causing big-bud symptoms. Transmission from the big-bud tomato to potato by grafting or the leafhopper Orosius argentatus resulted in the development of purple top wilt symptoms. Thin-section electron microscopy revealed mycoplasma-like organisms present in the phloem sieve elements of a big-bud tomato plant and purple top wilt potato plants infected by grafting or leafhoppers. When tubers from graft-infected potato plants were planted, 73% produced spindly shoots and 44% of these later developed purple top wilt symptoms. When scions from either field-infected or experimentally infected potato plants showing purple top wilt symptoms were grafted onto tomato plants, 24% and 62% respectively developed big-bud symptoms. The results provide strong evidence for the mycoplasmal aetiology of some, if not all, potato purple top wilt in Queensland.