“Laterite profiles” and “lateritic ironstones” on the hawkesbury sandstone,Australia

Laterite profiles in the Sydney area are generally regarded as fossil soils, formed during the Miocene, on a peneplain, under a tropical climate. It is also held that subsequent uplift and dissection destroyed much of this surface together with the laterite profiles. These views are poorly established yet widely accepted. This study demonstrates that there is a very close mineralogic and stratigraphic relationship between the “laterite profiles” and the Triassic Hawkesbury Sandstone, such that the profiles are best regarded as iron rich sandstone units undergoing contemporary near-surface alteration including the mobilization of iron minerals as crystalline solids.     

Quantification of the group B soyasaponins by high-performance liquid chromatography

High-performance liquid chromatographic methods were developed for the isolation and quantitative determination of the group B soyasaponins, including 2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP)-conjugated soyasaponins alphag, betag, and betaa, and their non-DDMP counterparts, soyasaponins V, I, and II, respectively, with formononetin used as the internal standard. The limits of quantification for soy products were 0.11-4.86 micromol/g. The within-day and between-days assay coefficients of variation were <9.8 and < 14.3%, respectively. The group B soyasaponin concentrations in 46 soybean varieties ranged from 2.50 to 5.85 micromol/g. Soy ingredients (soybean flour, toasted soy hypocotyls, soy protein isolates, textured vegetable protein, soy protein concentrates, and Novasoy) and soy foods (commercial soy milk, tofu, and tempeh) contained the group B soyasaponins from 0.20 to 114.02 micromol/g. There was no apparent correlation between isoflavone and soyasaponin concentrations in the soy products examined.     

The pelagic habitat analysis module for ecosystem‐based fisheries science and management

We have developed a set of tools that operate within an aquatic geographic information system to improve the accessibility, and usability of remote‐sensed satellite and computer‐modeled oceanographic data for marine science and ecosystem‐based management. The tools form the Pelagic Habitat Analysis Module (PHAM), which can be applied as a modeling platform, an investigative aid in scientific research, or utilized as a decision support system for marine ecological management. Applications include fisheries, marine biology, physical and biological oceanography, and marine spatial management. The GIS provides a home for diverse data types and automated tools for downloading remote sensed and global circulation model data. Within the GIS environment, PHAM provides a framework for seamless interactive four‐dimensional visualization, for matching between disparate data types, for flexible statistic or mechanistic model development, and for dynamic application of user developed models for habitat, density, and probability predictions. Here we describe PHAM in the context of ecosystem‐based fisheries management, and present results from case study projects which guided development. In the first, an analysis of the purse seine fishery for tropical tuna in the eastern Pacific Ocean revealed oceanographic drivers of the catch distribution and the influence of climate‐driven circulation patterns on the location of fishing grounds. To support management of the Common Thresher Shark (Alopias vulpinus) in the California Current Ecosystem, a simple empirical habitat utilization model was developed and used to dynamically predict the seasonal range expansion of common thresher shark based on oceanographic conditions.     

Trade-offs among establishment success,stem morphology and productivity of underplanted Toona ciliata: Effects of nurse-species and thinning density

Toona ciliata (Australian red cedar), a valuable hardwood species, requires a nurse-tree overstorey to prevent damage from frost and drought in some regions of north-eastern Argentina. Different nurse-species offer different degrees of protection, resource competition, and thinning revenues. In addition, choice of nurse-species will influence trade-offs between T. ciliata establishment success, stem quality and productivity as well as revenue from intermediate and final harvests. We tested the effects of overstorey species and planting density on underplanted T. ciliata survival, stem morphology and growth. Initial stand densities of nurse-species Pinus taeda (625 stems/ha), P. elliottii × P. caribaea (625 stems/ha), and Grevillea robusta (833 stems/ha) were thinned by 0%, 25%, 50%, and 75% in three experiments, each using a randomized block design. Initial mortality, light availability and growth of T. ciliata, as well as growth of its nurse-trees, were measured before and two years after thinning. In the third year, we characterized T. ciliata stem morphology (straightness and height-to-diameter-ratio) and destructively harvested a subsample of T. ciliata in order to investigate T. ciliata biomass production and allocation patterns in response to overstorey species, thinning density and light availability. T. ciliata mortality was lower when planted under G. robusta than the pines, and increased in plots with greater exposure to solar radiation. T. ciliata productivity was also greater under G. robusta than under the pines, and was generally greatest where any of the nurse-species were thinned by 75%. Stem form was best when growing under P. taeda and in stands thinned by 50%, regardless of nurse-species. With the exception of early mortality, light levels appeared to have limited effects on T. ciliata growth dynamics. Neither growth rate nor stem morphology was strongly correlated with light availability. Total overstorey basal-area was highest in P. taeda stands and individual overstorey tree growth generally increased with decreasing stand densities, except for slower height growth of G. robusta in more open stands. Thinning operations resulted in sawn-wood revenue for the pine species only. Because stand productivity and stem quality were optimized under different nurse-species and thinning treatments, we conclude that the choice of nurse-species and thinning intensity will depend on management objectives and will change with market preferences and conditions.     

Metal chelate molluscicides: The redistribution of iron diazaalkanolates from the gut lumen of the slug,Deroceras reticulatum (Müller) (Pulmonata: Limacidae)

Two related iron chelates, one toxic to slugs by ingestion, the other not, were introduced into the foregut of D. reticulatum. The subsequent movement and redistribution of the metal within the slug tissues was studied by labelling the chelates with the radioactive isotope ⁵⁵Fe. In slugs which survived treatment approximately half of the ⁵⁵Fe was voided in faeces. The iron retained became unevenly distributed, the highest concentration occurring in the digestive gland, irrespective of the chelate used. At high doses, slugs treated with tris(1-oxo-1,2-diazabutan-2-oxido)Fe(III) were fatally poisoned while those treated with the homologue, tris(1-oxo-1,2-diazaoctan-2-oxido)Fe(III) were not. Slugs killed by the toxic chelate consistently contained proportionally less iron in the digestive gland and proportionally more in the body wall and reproductive system. Dosing slugs already killed by carbon dioxide asphyxiation gave a similar pattern, suggesting that the greater mobility of the iron from the toxic chelate was not a function of the slugs' metabolism.     

Use of positive contrast rhinography and intranasal sinography for diagnosis of a nasofacial sinus tract in a dog

Twelve days after a dog fight, a 2-year-old sexually intact female Bulldog was evaluated because of subcutaneous emphysema of increasing severity throughout the dogs body. Thoracic radiography revealed severe pneumomediastinum from which free air had extended into the retroperitoneal space, resulting in pneumoperitoneum. Tracheoscopic examination did not reveal a discontinuity of the trachea, pharynx, or larynx. A breach between the nasal cavity and subcutaneous tissues of the nasal region was suspected. Further diagnostic investigations included positive contrast rhinography and intranasal sinography. Via an angiographic catheter inserted into the left naris, positive contrast intranasal sinography revealed a sinus tract extending between the left nasal cavity and the subcutaneous tissue of the dorsal aspect of the nasal planum. Resolution of subcutaneous emphysema, pneumomediastinum, and pneumoretroperitoneum began 1 day after surgical closure of the intranasal opening of the sinus tract. To the authors' knowledge, this radiographic technique has not been reported.     

Prevalence of caseous lymphadenitis and usage of caseous lymphadenitis vaccines in sheep flocks

OBJECTIVE: To estimate the prevalence of caseous lymphadenitis (CLA), determine the current usage of vaccines against CLA and to measure the effectiveness of these vaccines on sheep farms. DESIGN AND POPULATION: A survey was undertaken on 223 sheep flocks in New South Wales, Victoria and Western Australia. METHOD: The prevalence of CLA was measured by conventional inspection techniques at abattoirs in lines of sheep that could be traced back to a farm. Managers of the flocks were sent a questionnaire about their vaccine practices, management practices and knowledge of CLA. RESULTS: The average prevalence of CLA in adult sheep in these flocks was 26% and varied from 20% in Western Australia to 29% in New South Wales. About 43% of sheep producers used CLA vaccines; only 12% used them as recommended. Awareness of CLA was highest in Western Australia. More producers would use CLA vaccine if they knew the prevalence of CLA in their flock and producers obtained most information about CLA from vaccine resellers. CONCLUSIONS: Only 10 to 15% of producers are currently achieving effective CLA control through the use of recommended CLA vaccination programs. In Western Australian flocks more than 25% of effectively vaccinated ewes will be sent to abattoirs in the 2 to 3 years after this study. However, large decreases in the prevalence of CLA can be achieved by about 70% of producers by either making adjustments to their vaccination programs or buying a vaccine with a CLA component. Two or three key facts on effective CLA vaccination could be made available at the point of sale of vaccines and from abattoirs that reported the prevalence of CLA to farmers.     

Pancreatic exocrine secretion in steers infused postruminally with casein and cornstarch

Our objective was to evaluate the effect of postruminal protein infusion on pancreatic exocrine secretions. One Holstein, two crossbred, and five Angus steers (305 +/- 5 kg) with pancreatic pouch-duodenal reentrant cannulas and abomasal infusion catheters were used in a replicated 4 x 4 Latin square. All steers were abomasally infused with 1,050 g/d of raw cornstarch with treatments of 0, 60, 120, or 180 g/d of sodium casein suspended in water to yield 6,000 g/d of infusate daily. Steers were limit-fed (1.5 x NEm; 12 equal portions daily) a 90% corn silage, 10% supplement diet formulated to contain 12.5% CP. Periods consisted of 3 d of adaptation to infusion, 7 d of full infusion, 1 d of collection, and 7 d of rest. Pancreatic juice was collected in 30-min fractions continuously for 6 h. Total juice secreted and the pH of individual fractions were recorded, a 10% subsample was retained to form a composite sample, and remaining fluid was returned to the duodenum. Juice composite samples were stored (-30 degrees C) until analyzed for total protein and activities of alpha-amylase, trypsin, and chymotrypsin. Casein infusion linearly increased alpha-amylase concentration (182 to 271 units/mL; P < 0.02; 17.5 to 24.6 units/mg of protein; P < 0.03) and secretion rate (26,847 to 41,894 units/h; P < 0.01). Total juice secretion (155 g/h), pH of pancreatic juice (8.13), secretion rate of protein (1,536 mg/h), and concentration of protein (10.2 mg/mL) in pancreatic secretions were not affected (P > 0.05) by casein infusion. Similarly, casein infusion did not change 0.05) trypsin and chymotrypsin concentrations (1,379 and 349 units/L or 0.134 and 0.033 units/mg of protein, respectively) or secretion rates (206 and 52 units/h, respectively). Abomasal infusion of protein with starch stimulated a greater pancreatic secretion of alpha-amylase activity into the intestine than infusion of starch alone.     

Sodium nitroprusside-induced deliberate hypotension to facilitate patent ductus arteriosus ligation in dogs

OBJECTIVE: To report the use of sodium nitroprusside to induce deliberate hypotension to reduce hemorrhage and facilitate surgical ligation of complicated patent ductus arteriosus (PDA) in dogs. STUDY DESIGN: Retrospective study. ANIMALS: Six dogs. METHODS: Hemorrhage occurred during surgical ligation of PDA in 5 dogs. Surgical dissection and isolation of the PDA were very difficult in a sixth dog that was considered to be at increased risk for ductus rupture. Sodium nitroprusside (5 to 25 microg/kg/min intravenously) was administered to these 6 dogs to induce hypotension to reduce blood loss and facilitate surgical ligation of the PDA. RESULTS: Sodium nitroprusside infusion reduced blood pressure (mean arterial pressure, 45 to 60 mm Hg) within 5 to 10 minutes and hemorrhage from the PDA, facilitating its surgical ligation. Recovery from surgery and anesthesia was uneventful in all 6 dogs. CONCLUSIONS: Sodium nitroprusside infusion can be used to induce deliberate hypotension in dogs to facilitate surgical ligation of PDA. CLINICAL RELEVANCE: Sodium nitroprusside infusion produces hypotension within 5 to 10 minutes and is easy to control, rapidly abates, and should help to facilitate surgical ligation of PDA.