Biosecurity and food security—effective mechanisms for public-private partnerships

Maintaining Australia’s status as a major food exporter requires ongoing protection of its cropping industries from exotic pests and diseases. The number of pests classified as high priority threats to Australia’s plant industries now stands at over 300 (Plant Health Australia Annual Report 2014). It is often stated that Australia’s geographic isolation provides a natural barrier from many exotic pests that could damage plant production industries and the unique natural environment. Isolation, however, is not enough given that pests can enter through natural means or by being brought into the country with the increasing movements of people and goods. In an increasingly globalised world economy, Australia relies on a rigorous biosecurity system operated in partnership between governments and industry to mitigate risks from exotic pests. Steadily increasing trade volumes and passenger travel, global movements of serious pests, particularly into neighbouring countries, and the emergence of new and variant species of pests, will continue to test already stretched biosecurity capabilities. Plant Health Australia (PHA) provides the centrepiece of a unique system that manages the national preparedness and response for exotic plant pest incursions in Australia. PHA is a public company that facilitates decision making and funding for effective responses to emergency plant pests. PHA also independently advocates and adds value to, Australia’s national biosecurity system. Utilising the Emergency Plant Pest Response Deed (EPPRD), a legal agreement that brings together governments and industries in formal response arrangements, PHA ensures that national incursion responses are timely, science based, transparent and effective, with the aim of maintaining supply of quality clean food.     

In situ stabilisation/solidification: project lifecycle

The successful application of any remedial technology, including stabilisation/solidification, begins with the site investigation. Following a review of the data collected during the site investigation, a treatability study (TS) and pilot study (PS) are prerequisites to full-scale implementation as they show the effects and delivery of binders to the soils, the geochemistry of the soils, and binder dosages necessary for the existing geology. Further, evaluating the data gathered during the TS and PS can help in accurately estimating and executing full-scale operations. Invariably, deviations from the TS and PS regarding soil characteristics and soil chemistry may exist, but the experience gained via the TS and PS aids in making decisions when faced with new and unexpected conditions in the field. This paper will discuss the execution of typical TS and PS applications and their implementation for full-scale treatment. Because the long-term performance durability of design mixes and technology applications are not generally addressed in remediation, post-remediation monitoring and sampling data must be made available to the public to advance the science and art of stabilisation/solidification. As a first step in advancing this technology, this paper follows the lifecycle of stabilisation/ solidification projects from the site investigation through the completion of full-scale work. A 10-year post-remediation sampling event also evidences the long-term viability of the technology.     

Two-dimensional localization with a single diffuse ultrasound field excitation

Traditional ultrasound imaging methods rely on the bandwidth and center frequency of transduction to achieve axial and radial image resolution, respectively. In this study, a new modality for spatially localizing scattering targets in a two-dimensional field is presented. In this method, the bandwidth of field excitation is high, and the center frequency is lowered such that the corresponding wavelengths are substantially larger than the target profiles. Furthermore, full two-dimensional field measurements are obtained with single send-receive sequences, demonstrating a substantial simplification of the traditional scanning techniques. Field reconstruction is based on temporal-spectral cross-correlations between measured backscatter data and a library of region of interest (ROI) backscatter data measured a priori. The transducer design is based upon a wedge-shaped geometry, which was shown to yield spatially frequency-separated bandwidths of up to 156% with center frequencies of 1.38 MHz. Initial results with these send-and-receive transducer parameters and cylindrical reflection targets in a 10-mm x 10-mm ROI demonstrate two-dimensional target localization to within 0.5 mm. Spatial localization of point scatterers is demonstrated for single and multiple scattering sites.     

Revising the machine smoking regime for cigarette emissions: implications for tobacco control policy

Background

The WHO Framework Convenion on Tobacco Control includes provisions for testing and regulating cigarette emissions. However, the current international standard for generating cigarette emissions—the ISO machine smoking regime—is widely acknowledged to be inappropriate for purposes of setting regulatory restrictions.

Objective

To review alternatives to the ISO machine smoking regime and the extent to which they: 1) Represent human smoking behaviour, 2) Reduce the potential for industry exploitation, particularly in the area of risk communication, and 3) Serve as suitable measures for product regulation.

Methods

Emissions data from 238 Canadian cigarette brands tested under the ISO and “Canadian Intense” machine smoking regimes.

Results

None of the alternative smoking regimes, including the Canadian Intense method, are more “representative” of human smoking behaviour and none provide better predictors of human exposure.

Conclusions

Given that alternatives such as the Canadian Intense regime are subject to the same fundamental limitations as the ISO regime, key questions need to be addressed before any smoking regime should be used to set regulatory limits on smoke emissions. In the meantime, regulators should remove quantitative emission values from cigarette packages and more work should be done on alternative machine smoking methods.The issue of how to test and regulate conventional cigarettes represents a critical challenge for tobacco control. To date, the primary means of testing cigarette toxicity has been to machine smoke the cigarettes according to a standard puffing regime and to measure the chemical emissions in the mainstream smoke. In many jurisdictions, these cigarette “yields” are printed on packages and represent the only source of information on constituents or toxicity available to consumers. Cigarette emissions also serve as a regulatory standard in several of jurisdictions, including the European Union, where brands that generate emissions >10 mg of tar, 1 mg of nicotine or 10 ppm of carbon monoxide are prohibited. The puffing regime used to machine smoke the cigarettes—the International Organization for Standardization (ISO) regime¹—is widely recognised to be inadequate for the purposes of product regulation or consumer information. The ISO regime constitutes a set of puffing parameters that systematically underestimate smoking behaviour in humans.^2,3,4 Tobacco manufacturers have also designed cigarette brands to perform one way under the machine smoking conditions, but to deliver much greater smoke constituents to humans.^5,6 As a result, the emissions generated under the ISO smoking regime have little relationship with actual measures of human exposure, and exaggerate the differences between brands in a manner that has proved deceptive to both consumers and regulators.^7,8,9 Overall, the emissions from the ISO regime have served as more of an industry marketing tool to falsely reassure health‐concerned smokers, rather than as a valid measure of cigarette toxicity.^2,10,11,12There is a growing movement to develop a more meaningful machine testing method. The World Health Organization''s Framework Convention on Tobacco Control (FCTC)—the world''s first international public health treaty—includes provisions for testing and regulating cigarette emissions under Article 9.¹³ These provisions will need to be specified now that the FCTC has come into force. After discussions with the WHO, the ISO convened a working group (ISO TC 126 WG9) to develop recommendations for “…a robust and practical smoking regime that as far as possible is representative of smokers'' behaviour”. Meanwhile, the World Health Organization''s Study Group on Tobacco Product Regulations (WHO TobReg) has developed its own set of recommendations, which were under consideration by the ISO Working Group.¹⁴ There are also concerns that the ISO committee structure responsible for setting tobacco standards is dominated by the tobacco industry.¹²Before any new testing regime is implemented, it is critical to ensure that the new standards will serve the interests of public health rather than the tobacco industry. The purpose of this paper is to review the smoking regimes that are under consideration by the ISO Working Group, and to examine the implications for tobacco control policy and product regulation. In particular, we examine the extent to which the proposed regimes will: (1) succeed in “representing” smoking behaviour in humans and generate better predictors of human exposure; (2) reduce the potential for industry exploitation, particularly in the field of risk communication; and (3) help to establish more effective regulatory limits on cigarette toxicity.     

Supercritical carbon dioxide extraction of lipids from Pythium irregulare

Lipids that contain polyunsaturated fatty acids (PUFA) have therapeutic value. PUFA, however, degrade in high-temperature, oxygen-rich conditions typical of conventional hot solvent-extraction and distillation methods. Supercritical CO₂ extraction was chosen as an alternative method to recover these valuable compounds from the lower fungus, Pythium irregulare. Freeze-dried biomass was subjected to an aqueous phase and placed into a flow-through extraction apparatus. Extraction of oil from this biomass showed some success for moisture contents as high as 30% (wet basis). The addition of a novel CO₂-philic surfactant to the wet biomass with moisture contents as high as 95% (wet basis) increased the extraction rate of fungal oil by more than an order of magnitude. For tests with extraction times of 5 to 6 h, data for the diffusion-controlled region were modeled with an analytical solution to Fick’s second law. Equilibrium data were also obtained for the fungal oil at two isotherms (40 and 60°C) over a pressure range of 13.7 to 27.5 MPa.     

Physical and frictional properties of non-treated and steam exploded barley, canola, oat and wheat straw grinds

During storage and handling, accurate knowledge of the physical and frictional behaviors of biomass grinds is essential for the efficient design of equipment. Therefore, experiments were performed on non-treated and steam exploded barley, canola, oat and wheat straw grinds to determine their coefficient of internal friction and cohesion at three hammer mill screen sizes of 6.4, 3.2 and 1.6 mm, three normal stress values of 9.8, 19.6 and 39.2 kPa at 10% moisture content (wb). At any specific hammer mill screen size, the geometric mean particle size and bulk density of non-treated straw was significantly larger than steam exploded straw. The bulk density of ground straw significantly increased with a decrease in hammer mill screen sizes. The steam exploded straw grinds resulted in higher coefficient of internal friction compared to non-treated straw grinds primarily because of lower bulk densities. The coefficient of friction for non-treated barley, canola, oat and wheat straw were in the range of 0.505 to 0.584, 0.661 to 0.665, 0.498 to 0.590, and 0.532 to 0.591, respectively. Similarly, the coefficient of friction for steam exploded barley, canola, oat and wheat straw were in the range of 0.562 to 0.738, 0.708 to 0.841, 0.660 to 0.860, and 0.616 to 1.036, respectively, which were higher than non-treated straw of the kind. Power, logarithmic or exponential equations were developed to predict the coefficient of internal friction and cohesion with respect to average geometric mean particle sizes for non-treated and steam explode barley, canola, oat and wheat straw grinds.     

Organic–Inorganic Hybrid Films Based on Hydroxylated Soybean Oils

Hybrid organic–inorganic films were prepared using four different hydroxylated soybean oils (HSO) or epoxidized soybean oil as organic precursor and tetraethyl orthosilicate (TEOS) as inorganic precursor in a mass ratio of HSO:TEOS of 90:10. The films were macroscopically homogeneous and were characterized by swelling and extraction in solvent, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) including energy dispersive spectroscopy (EDX), adhesion and hardness. Their properties varied as a function of the number of OH groups present in the HSO. The best hybrid system was HSOF198/TEOS, with an OH value of 198 mg of KOH/g, which presents lower swelling coefficient, very good adhesion on aluminium surface and good hardness.     

Pathogenesis of oleic acid-induced lung injury in the rat: Distribution of oleic acid during injury and early endothelial cell changes

Oleic acid-induced lung injury, a well-described laboratory model for acute pulmonary injury in the rat and other species, causes morphologic and cellular changes similar to human adult respiratory distress syndrome (ARDS). Experiments were performed to test the hypothesis that the initial event of oleic acid lung injury is damage of the pulmonary vascular endothelium by oleic acid, with subsequent pulmonary damage and inflammation. Oleic acid levels were followed in the lung and other tissues by measuring accumulation of¹⁴C-oleic acid; the direct effects of oleic acid and other fatty acids on rat endothelial cells, alveolar type II cells, and hepatocytes in culture were determined. Lung tissue from treated rats was also examined by light and electron microscopy for evidence of endothelial cell damage. At 30 min after injury, oleic acid reached high concentrations in lung tissue as demonstrated by presence of radiolabel (3.24×10⁻⁶ moles per gram of tissue), with counts in the lung nearly an order of magnitude greater than in any other organ measured. Oleic acid was present in the lung mostly as free fatty acid (85%), and was also present in the alveolar fluid supernatans, rather than being cell-associated (1.7×10⁻⁷ moles vs. 1.1×10⁻⁸ moles at 30 min). Oleic acid was toxic to endothelial cells after one minute of exposure at concentrations of 5×10⁻⁴M and above. Electron microscopy showed endothelial cell changes as early as 10 min after induction of injuryin vivo, including the presence of endothelial cell blebbing. The results of these studies suggest that the initial event in oleic acid lung injury is damage to the pulmonary vascular endothelial cell.