Development of a transformation system for sorghum (Sorghum bicolor L.)

Sorghum (Sorghum bicolor (L.) Moench) is the world’s fifth major cereal crop and holds importance as a construction material, food and fodder source. More recently, the potential of this plant as a biofuel source has been noted. Despite its agronomic importance, the use of sorghum production is being constrained by both biotic and abiotic factors. These challenges could be addressed by the use of genetic engineering strategies to complement conventional breeding techniques. However, sorghum is one of the most recalcitrant crops for genetic modification with the lack of an efficient tissue culture system being amongst the chief reasons. Therefore, the aim of this study was to develop an efficient tissue culture system for establishing regenerable embryogenic cell lines, micropropagation and acclimatisation for Sorghum bicolor and use this to optimise parameters for genetic transformation via Agrobacterium-mediated transformation and microprojectile bombardment. Using five different sorghum cultivars, SA281, 296B, SC49, Wray and Rio, numerous parameters were investigated in an attempt to establish an efficient and reproducible tissue culture and transformation system. Using immature embryos (IEs) as explants, regenerable embryogenic cell lines (ECLs) could only be established from cultivars SA281 and 296B. Large amounts of phenolics were produced from IEs of cultivars, SC49, Wary and Rio, and these compounds severely hindered callus formation and development. Cultivar SA281 also produced phenolics during regeneration. Attempts to suppress the production of these compounds in cultivars SA281 and SC49 using activated charcoal, PVP, ascorbic acid, citric acid and liquid filter paper bridge methods were either ineffective or had a detrimental effect on embryogenic callus formation, development and regeneration. Immature embryos sourced during summer were found to be far more responsive in vitro than those sourced during winter. In an attempt to overcome this problem, IEs were sourced from sorghum grown under summer conditions in either a temperature controlled glasshouse or a growth chamber. However, the performance of these explants was still inferior to that of natural summer-sourced explants. Leaf whorls, mature embryos, shoot tips and leaf primordia were found to be unsuitable as explants for establishing ECLs in sorghum cultivars SA281 and 296B. Using the florets of immature inflorescences (IFs) as explants, however, ECLs were established and regenerated for these cultivars, as well as for cultivar Tx430, using callus induction media, SCIM, and regeneration media, VWRM. The best in vitro responses, from the largest possible sized IFs, were obtained using plants at the FL-2 stage (where the last fully opened leaf was two leaves away from the flag leaf). Immature inflorescences could be stored at 25oC for up to three days without affecting their in vitro responses. Compared to IEs, the IFs were more robust in tissue culture and showed responses which were season and growth condition independent. A micropropagation protocol for sorghum was developed in this study. The optimum plant growth regulator (PGR) combination for the micropropagation of in vitro regenerated plantlets was found to be 1.0 mg/L BAP in combination with 0.5 mg/L NAA. With this protocol, cultivars 296B and SA281 produced an average of 57 and 13 off-shoots per plantlet, respectively. The plantlets were successfully acclimatised and developed into phenotypically normal plants that set seeds. A simplified acclimatisation protocol for in vitro regenerated plantlets was also developed. This protocol involved deflasking in vitro plantlets with at least 2 fully-opened healthy leaves and at least 3 roots longer than 1.5 cm, washing the media from the roots with running tap water, planting in 100 mm pots and placing in plastic trays covered with a clear plastic bag in a plant growth chamber. After seven days, the corners of the plastic cover were opened and the bags were completely removed after 10 days. All plantlets were successfully acclimatised regardless of whether 1:1 perlite:potting mix, potting mix, UC mix or vermiculite were used as potting substrates. Parameters were optimised for Agrobacterium-mediated transformation (AMT) of cultivars SA281, 296B and Tx430. The optimal conditions were the use of Agrobacterium strain LBA4404 at an inoculum density of 0.5 OD600nm, heat shock at 43oC for 3 min, use of the surfactant Pluronic F-68 (0.02% w/v) in the inoculation media with a pH of 5.2 and a 3 day co-cultivation period in dark at 22oC. Using these parameters, high frequencies of transient GFP expression was observed in IEs precultured on callus initiation media for 1-7 days as well as in four weeks old IE- and IF-derived callus. Cultivar SA281 appeared very sensitive to Agrobacterium since all tissue turned necrotic within two weeks post-exposure. For cultivar 296B, GFP expression was observed up to 20 days post co-cultivation but no stably transformed plants were regenerated. Using cultivar Tx430, GFP was expressed for up to 50 days post co-cultivation. Although no stably transformed plants of this cultivar were regenerated, this was most likely due to the use of unsuitable regeneration media. Parameters were optimised for transformation by particle bombardment (PB) of cultivars SA281, 296B and Tx430. The optimal conditions were use of 3-7 days old IEs and 4 weeks old IF callus, 4 hour pre- and post-bombardment osmoticum treatment, use of 0.6 µm gold microparticles, helium pressure of 1500 kPa and target distance of 15 cm. Using these parameters for PB, transient GFP expression was observed for up to 14, 30 and 50 days for cultivars SA281, 296B and Tx430, respectively. Further, the use of PB resulted in less tissue necrosis compared to AMT for the respective cultivars. Despite the presence of transient GFP expression, no stably transformed plants were regenerated. The establishment of regenerable ECLs and the optimization of AMT and PB parameters in this study provides a platform for future efforts to develop an efficient transformation protocol for sorghum. The development of GM sorghum will be an important step towards improving its agronomic properties as well as its exploitation for biofuel production.

Benign Epilepsy with Centro-temporal Spikes: Spike Triggered fMRI Shows Somato-sensory Cortex Activity

Summary:  Objective: We performed spike triggered functional MRI (fMRI) in a 12 year old girl with Benign Epilepsy with Centro-temporal Spikes (BECTS) and left-sided spikes. Our aim was to demonstrate the cerebral origin of her interictal spikes. Methods: EEG was recorded within the 3 Tesla MRI. Whole brain fMRI images were acquired, beginning 2–3 seconds after spikes. Baseline fMRI images were acquired when there were no spikes for 20 seconds. Image sets were compared with the Student's t-test. Results: Ten spike and 20 baseline brain volumes were analysed. Focal activiation was seen in the inferior left sensorimotor cortex near the face area. The anterior cingulate was more active during baseline than spikes. Conclusions: Left sided epileptiform activity in this patient with BECTS is associated with fMRI activation in the left face region of the somatosensory cortex, which would be consistent with the facial sensorimotor involvement in BECT seizures. The presence of BOLD signal change in other regions raises the possibility that the scalp recorded field of this patient with BECTs may reflect electrical change in more than one brain region.

District Court of Queensland Act 1968 s 68 : jurisdiction in pre-proceedings applications under Personal Injuries Proceedings Act 2002

In Woolworths Ltd v Graham [2007] QDC 301 Searles DCJ struck out a pre-proceedings application under the Personal Injuries Proceedings Act 2002 (Qld)on the basis that the material before the Court was not sufficient to attract the jurisdiction of the District Court.The decision serves more broadly as a reminder that the District Court is an inferior court of defined and limited jurisdiction and that any proceedings brought in it must be demonstrably within the jurisdiction conferred on that court by legislation.

Metacognitive strategy instruction in English as Foreign Language (EFL) listening skill

Listening skill is a critical part of language learning in general, and second, and foreign language learning, in particular. However, the process of this basic skill has been overlooked compared to other skills such as speaking, reading and writing, in terms of an explicit instruction, and the product of listening is instead mainly tested indirectly through comprehension questions in classrooms. Instruction of metacognitive strategies demonstrates the pivotal impact on second language listening skill development. In this vein, this study used a mixed method with an experimental male group (N = 30) listened to texts using process-approach pedagogy directed students through metacognitive strategies over a semester (10 weeks) in Iran. To investigate the impact of metacognitive strategy instruction, the following approaches were implemented. First, IELTS listening test was used to track any development of listening comprehension. Second, using Vandergrift et al. (2006) Metacognitive Awareness Listening Questionnaire (MALQ) helped examine students’ use of metacognitive strategies in listening comprehension. Finally, interviews were used to examine students’ use of strategies in listening. The results showed that students had a development in comprehension of IELTS listening test, but no statistical significant development of metacognitive awareness in listening was demonstrated. Students and teacher reported in the interviews students used multiple strategies to approach listening comprehension besides metacognitive strategies.

Fire Tests of Cold-formed Steel Wall Systems

Cold-formed steel stud walls are an important component of Light Steel Framing (LSF) building systems used in commercial, industrial and residential buildings. In the conventional LSF stud wall systems, thin-walled steel studs are protected from fire by placing one or two layers of plasterboard on both sides with or without cavity insulation. However, there is very limited data about the structural and thermal performance of these wall systems while past research showed contradicting results about the benefits of cavity insulation. This research proposed a new LSF stud wall system in which a composite panel made of two plasterboards with insulation between them was used to improve the fire rating of walls. Full scale fire tests were conducted using both conventional steel stud walls with and without the use of cavity insulation and the new composite panel system. Eleven full scale load bearing wall specimens were tested to study the thermal and structural performances of the load bearing wall assemblies under standard fire conditions. These tests showed that the use of cavity insulation led to inferior fire performance of walls while also providing good explanations and supporting test data to overcome the incorrect industry assumptions about cavity insulation. Tests demonstrated that the use of external insulation in a composite panel form enhanced the thermal and structural performances of stud walls and increased their fire resistance rating significantly. This paper presents the details of the full scale fire tests of load-bearing wall assemblies lined with plasterboards and different types of insulation under varying load ratios. Test results including the temperature and deflection profiles of walls measured during the fire tests will be presented along with their failure modes and failure times.

Gifts, the law and functional rationalism

This paper examines the legal facilitation (or rather lack of facilitation) of gifts. The emerging western political ideology of welfare is based on the premise that nonprofit organisations are to play a far greater role in the delivery of welfare services. This role will be enabled in part by increased gifts. The ideology has not addressed the fundamental hostility of the law to the facilitation of gifts. The nature of the legal obstruction of such gifts is compared to equivalent commercial transactions, the reasons given for this obstruction are analysed and the appropriateness of such nonfacilitation is challenged. A state that does not alter the legal hostility to gifts may find that organisations do not attain their expected role in the changing welfare state.

Preparation, characterization and in vitro angiogenic capacity of cobalt substituted β-tricalcium phosphate ceramics

Divalent cobalt ions (Co2+) have been shown to possess the capacity to induce angiogenesis by activating hypoxia inducible factor-1α (HIF-1α) and subsequently inducing the production of vascular endothelial growth factor (VEGF). However, there are few reports about Co-containing biomaterials for inducing in vitro angiogenesis. The aim of the present work was to prepare Co-containing β-tricalcium phosphate (Co-TCP) ceramics with different contents of calcium substituted by cobalt (0, 2, 5 mol%) and to investigate the effect of Co substitution on their physicochemical and biological properties. Co-TCP powders were synthesized by a chemistry precipitation method and Co-TCP ceramics were prepared by sintering the powder compacts. The effect of Co substitution on phase transition and the sintering property of the β-TCP ceramics was investigated. The proliferation and VEGF expression of human bone marrow mesenchymal stem cells (HBMSCs) cultured with both powder extracts and ceramic discs of Co-TCP was further evaluated. The in vitro angiogenesis was evaluated by the tube-like structure formation of human umbilical vein endothelial cells (HUVECs) cultured on ECMatrix™ in the presence of powder extracts. The results showed that Co substitution suppressed the phase transition from β- to α-TCP. Both the powder extracts and ceramic discs of Co-TCP had generally good cytocompatibility to support HBMSC growth. Importantly, the incorporation of Co into β-TCP greatly stimulated VEGF expression of HBMSCs and Co-TCP showed a significant enhancement of network structure formation of HUVECs compared with pure TCP. Our results suggested that the incorporation of Co into bioceramics is a potential viable way to enhance angiogenic properties of biomaterials. Co-TCP bioceramics may be used for bone tissue regeneration with improved angiogenic capacity.

Reversal of acute coagulopathy during hypotensive resuscitation using small-volume 7.5% NaCl adenocaine and Mg2+ in the rat model of severe hemorrhagic shock

OBJECTIVE: : Acute traumatic coagulopathy occurs early in hemorrhagic trauma and is a major contributor to mortality and morbidity. Our aim was to examine the effect of small-volume 7.5% NaCl adenocaine (adenosine and lidocaine, adenocaine) and Mg on hypotensive resuscitation and coagulopathy in the rat model of severe hemorrhagic shock. DESIGN: : Prospective randomized laboratory investigation. SUBJECTS: : A total of 68 male Sprague Dawley Rats. INTERVENTION: : Post-hemorrhagic shock treatment for acute traumatic coagulopathy. MEASUREMENTS AND METHODS: : Nonheparinized male Sprague-Dawley rats (300-450 g, n = 68) were randomly assigned to either: 1) untreated; 2) 7.5% NaCl; 3) 7.5% NaCl adenocaine; 4) 7.5% NaCl Mg; or 5) 7.5% NaCl adenocaine/Mg. Hemorrhagic shock was induced by phlebotomy to mean arterial pressure of 35-40 mm Hg for 20 mins (~40% blood loss), and animals were left in shock for 60 mins. Bolus (0.3 mL) was injected into the femoral vein and hemodynamics monitored. Blood was collected in Na citrate (3.2%) tubes, centrifuged, and the plasma snap frozen in liquid N2 and stored at -80°C. Coagulation was assessed using activated partial thromboplastin times and prothrombin times. RESULTS: : Small-volume 7.5% NaCl adenocaine and 7.5% NaCl adenocaine/Mg were the only two groups that gradually increased mean arterial pressure 1.6-fold from 38-39 mm Hg to 52 and 64 mm Hg, respectively, at 60 mins (p < .05). Baseline plasma activated partial thromboplastin time was 17 ± 0.5 secs and increased to 63 ± 21 secs after bleeding time, and 217 ± 32 secs after 60-min shock. At 60-min resuscitation, activated partial thromboplastin time values for untreated, 7.5% NaCl, 7.5% NaCl/Mg, and 7.5% NaCl adenocaine rats were 269 ± 31 secs, 262 ± 38 secs, 150 ± 43 secs, and 244 ± 38 secs, respectively. In contrast, activated partial thromboplastin time for 7.5% NaCl adenocaine/Mg was 24 ± 2 secs (p < .05). Baseline prothrombin time was 28 ± 0.8 secs (n = 8) and followed a similar pattern of correction. CONCLUSIONS: : Plasma activated partial thromboplastin time and prothrombin time increased over 10-fold during the bleed and shock periods prior to resuscitation, and a small-volume (~1 mL/kg) IV bolus of 7.5% NaCl AL/Mg was the only treatment group that raised mean arterial pressure into the permissive range and returned activated partial thromboplastin time and prothrombin time clotting times to baseline at 60 mins.

Wide-field assessment of the human corneal subbasal nerve plexus in diabetic neuropathy using a novel mapping technique

To develop a rapid optimized technique of wide-field imaging of the human corneal subbasal nerve plexus. A dynamic fixation target was developed and, coupled with semiautomated tiling software, a rapid method of capturing and montaging multiple corneal confocal microscopy images was created. To illustrate the utility of this technique, wide-field maps of the subbasal nerve plexus were produced in 2 participants with diabetes, 1 with and 1 without neuropathy. The technique produced montages of the central 3 mm of the subbasal corneal nerve plexus. The maps seem to show a general reduction in the number of nerve fibers and branches in the diabetic participant with neuropathy compared with the individual without neuropathy. This novel technique will allow more routine and widespread use of subbasal nerve plexus mapping in clinical and research situations. The significant reduction in the time to image the corneal subbasal nerve plexus should expedite studies of larger groups of diabetic patients and those with other conditions affecting nerve fibers. The inferior whorl and the surrounding areas may show the greatest loss of nerve fibers in individuals with diabetic neuropathy, but this should be further investigated in a larger cohort.

Retinal nerve fibre layer thinning associated with diabetic peripheral neuropathy

Aims:  To investigate the relationship between retinal nerve fibre layer thickness and peripheral neuropathy in patients with Type 2 diabetes, particularly in those who are at higher risk of foot ulceration. Methods:  Global and sectoral retinal nerve fibre layer thicknesses were measured at 3.45 mm diameter around the optic nerve head using optical coherence tomography (OCT). The level of neuropathy was assessed in 106 participants (82 with Type 2 diabetes and 24 healthy controls) using the 0–10 neuropathy disability score. Participants were stratified into four neuropathy groups: none (0–2), mild (3–5), moderate (6–8), and severe (9–10). A neuropathy disability score ≥ 6 was used to define those at higher risk of foot ulceration. Multivariable regression analysis was performed to assess the effect of neuropathy disability scores, age, disease duration and retinopathy on RNFL thickness. Results:  Inferior (but not global or other sectoral) retinal nerve fibre layer thinning was associated with higher neuropathy disability scores (P = 0.03). The retinal nerve fibre layer was significantly thinner for the group with neuropathy disability scores ≥ 6 in the inferior quadrant (P < 0.005). Age, duration of disease and retinopathy levels did not significantly influence retinal nerve fibre layer thickness. Control participants did not show any significant differences in thickness measurements from the group with diabetes and no neuropathy (P > 0.24 for global and all sectors). Conclusions:  Inferior quadrant retinal nerve fibre layer thinning is associated with peripheral neuropathy in patients with Type 2 diabetes, and is more pronounced in those at higher risk of foot ulceration.

Performance evaluation of onsite sewage treatment : Evaluation of current research

Efficient management of domestic wastewater is a primary requirement for human well being. Failure to adequately address issues of wastewater collection, treatment and disposal can lead to adverse public health and environmental impacts. The increasing spread of urbanisation has led to the conversion of previously rural land into urban developments and the more intensive development of semi urban areas. However the provision of reticulated sewerage facilities has not kept pace with this expansion in urbanisation. This has resulted in a growing dependency on onsite sewage treatment. Though considered only as a temporary measure in the past, these systems are now considered as the most cost effective option and have become a permanent feature in some urban areas. This report is the first of a series of reports to be produced and is the outcome of a research project initiated by the Brisbane City Council. The primary objective of the research undertaken was to relate the treatment performance of onsite sewage treatment systems with soil conditions at site, with the emphasis being on septic tanks. This report consists of a ‘state of the art’ review of research undertaken in the arena of onsite sewage treatment. The evaluation of research brings together significant work undertaken locally and overseas. It focuses mainly on septic tanks in keeping with the primary objectives of the project. This report has acted as the springboard for the later field investigations and analysis undertaken as part of the project. Septic tanks still continue to be used widely due to their simplicity and low cost. Generally the treatment performance of septic tanks can be highly variable due to numerous factors, but a properly designed, operated and maintained septic tank can produce effluent of satisfactory quality. The reduction of hydraulic surges from washing machines and dishwashers, regular removal of accumulated septage and the elimination of harmful chemicals are some of the practices that can improve system performance considerably. The relative advantages of multi chamber over single chamber septic tanks is an issue that needs to be resolved in view of the conflicting research outcomes. In recent years, aerobic wastewater treatment systems (AWTS) have been gaining in popularity. This can be mainly attributed to the desire to avoid subsurface effluent disposal, which is the main cause of septic tank failure. The use of aerobic processes for treatment of wastewater and the disinfection of effluent prior to disposal is capable of producing effluent of a quality suitable for surface disposal. However the field performance of these has been disappointing. A significant number of these systems do not perform to stipulated standards and quality can be highly variable. This is primarily due to houseowner neglect or ignorance of correct operational and maintenance procedures. The other problems include greater susceptibility to shock loadings and sludge bulking. As identified in literature a number of design features can also contribute to this wide variation in quality. The other treatment processes in common use are the various types of filter systems. These include intermittent and recirculating sand filters. These systems too have their inherent advantages and disadvantages. Furthermore as in the case of aerobic systems, their performance is very much dependent on individual houseowner operation and maintenance practices. In recent years the use of biofilters has attracted research interest and particularly the use of peat. High removal rates of various wastewater pollutants have been reported in research literature. Despite these satisfactory results, leachate from peat has been reported in various studies. This is an issue that needs further investigations and as such biofilters can still be considered to be in the experimental stage. The use of other filter media such as absorbent plastic and bark has also been reported in literature. The safe and hygienic disposal of treated effluent is a matter of concern in the case of onsite sewage treatment. Subsurface disposal is the most common and the only option in the case of septic tank treatment. Soil is an excellent treatment medium if suitable conditions are present. The processes of sorption, filtration and oxidation can remove the various wastewater pollutants. The subsurface characteristics of the disposal area are among the most important parameters governing process performance. Therefore it is important that the soil and topographic conditions are taken into consideration in the design of the soil absorption system. Seepage trenches and beds are the common systems in use. Seepage pits or chambers can be used where subsurface conditions warrant, whilst above grade mounds have been recommended for a variety of difficult site conditions. All these systems have their inherent advantages and disadvantages and the preferable soil absorption system should be selected based on site characteristics. The use of gravel as in-fill for beds and trenches is open to question. It does not contribute to effluent treatment and has been shown to reduce the effective infiltrative surface area. This is due to physical obstruction and the migration of fines entrained in the gravel, into the soil matrix. The surface application of effluent is coming into increasing use with the advent of aerobic treatment systems. This has the advantage that treatment is undertaken on the upper soil horizons, which is chemically and biologically the most effective in effluent renovation. Numerous research studies have demonstrated the feasibility of this practice. However the overriding criteria is the quality of the effluent. It has to be of exceptionally good quality in order to ensure that there are no resulting public health impacts due to aerosol drift. This essentially is the main issue of concern, due to the unreliability of the effluent quality from aerobic systems. Secondly, it has also been found that most householders do not take adequate care in the operation of spray irrigation systems or in the maintenance of the irrigation area. Under these circumstances surface disposal of effluent should be approached with caution and would require appropriate householder education and stringent compliance requirements. However despite all this, the efficiency with which the process is undertaken will ultimately rest with the individual householder and this is where most concern rests. Greywater too should require similar considerations. Surface irrigation of greywater is currently being permitted in a number of local authority jurisdictions in Queensland. Considering the fact that greywater constitutes the largest fraction of the total wastewater generated in a household, it could be considered to be a potential resource. Unfortunately in most circumstances the only pretreatment that is required to be undertaken prior to reuse is the removal of oil and grease. This is an issue of concern as greywater can considered to be a weak to medium sewage as it contains primary pollutants such as BOD material and nutrients and may also include microbial contamination. Therefore its use for surface irrigation can pose a potential health risk. This is further compounded by the fact that most householders are unaware of the potential adverse impacts of indiscriminate greywater reuse. As in the case of blackwater effluent reuse, there have been suggestions that greywater should also be subjected to stringent guidelines. Under these circumstances the surface application of any wastewater requires careful consideration. The other option available for the disposal effluent is the use of evaporation systems. The use of evapotranspiration systems has been covered in this report. Research has shown that these systems are susceptible to a number of factors and in particular to climatic conditions. As such their applicability is location specific. Also the design of systems based solely on evapotranspiration is questionable. In order to ensure more reliability, the systems should be designed to include soil absorption. The successful use of these systems for intermittent usage has been noted in literature. Taking into consideration the issues discussed above, subsurface disposal of effluent is the safest under most conditions. This is provided the facility has been designed to accommodate site conditions. The main problem associated with subsurface disposal is the formation of a clogging mat on the infiltrative surfaces. Due to the formation of the clogging mat, the capacity of the soil to handle effluent is no longer governed by the soil’s hydraulic conductivity as measured by the percolation test, but rather by the infiltration rate through the clogged zone. The characteristics of the clogging mat have been shown to be influenced by various soil and effluent characteristics. Secondly, the mechanisms of clogging mat formation have been found to be influenced by various physical, chemical and biological processes. Biological clogging is the most common process taking place and occurs due to bacterial growth or its by-products reducing the soil pore diameters. Biological clogging is generally associated with anaerobic conditions. The formation of the clogging mat provides significant benefits. It acts as an efficient filter for the removal of microorganisms. Also as the clogging mat increases the hydraulic impedance to flow, unsaturated flow conditions will occur below the mat. This permits greater contact between effluent and soil particles thereby enhancing the purification process. This is particularly important in the case of highly permeable soils. However the adverse impacts of the clogging mat formation cannot be ignored as they can lead to significant reduction in the infiltration rate. This in fact is the most common cause of soil absorption systems failure. As the formation of the clogging mat is inevitable, it is important to ensure that it does not impede effluent infiltration beyond tolerable limits. Various strategies have been investigated to either control clogging mat formation or to remediate its severity. Intermittent dosing of effluent is one such strategy that has attracted considerable attention. Research conclusions with regard to short duration time intervals are contradictory. It has been claimed that the intermittent rest periods would result in the aerobic decomposition of the clogging mat leading to a subsequent increase in the infiltration rate. Contrary to this, it has also been claimed that short duration rest periods are insufficient to completely decompose the clogging mat, and the intermediate by-products that form as a result of aerobic processes would in fact lead to even more severe clogging. It has been further recommended that the rest periods should be much longer and should be in the range of about six months. This entails the provision of a second and alternating seepage bed. The other concepts that have been investigated are the design of the bed to meet the equilibrium infiltration rate that would eventuate after clogging mat formation; improved geometry such as the use of seepage trenches instead of beds; serial instead of parallel effluent distribution and low pressure dosing of effluent. The use of physical measures such as oxidation with hydrogen peroxide and replacement of the infiltration surface have been shown to be only of short-term benefit. Another issue of importance is the degree of pretreatment that should be provided to the effluent prior to subsurface application and the influence exerted by pollutant loadings on the clogging mat formation. Laboratory studies have shown that the total mass loadings of BOD and suspended solids are important factors in the formation of the clogging mat. It has also been found that the nature of the suspended solids is also an important factor. The finer particles from extended aeration systems when compared to those from septic tanks will penetrate deeper into the soil and hence will ultimately cause a more dense clogging mat. However the importance of improved pretreatment in clogging mat formation may need to be qualified in view of other research studies. It has also shown that effluent quality may be a factor in the case of highly permeable soils but this may not be the case with fine structured soils. The ultimate test of onsite sewage treatment system efficiency rests with the final disposal of effluent. The implication of system failure as evidenced from the surface ponding of effluent or the seepage of contaminants into the groundwater can be very serious as it can lead to environmental and public health impacts. Significant microbial contamination of surface and groundwater has been attributed to septic tank effluent. There are a number of documented instances of septic tank related waterborne disease outbreaks affecting large numbers of people. In a recent incident, the local authority was found liable for an outbreak of viral hepatitis A and not the individual septic tank owners as no action had been taken to remedy septic tank failure. This illustrates the responsibility placed on local authorities in terms of ensuring the proper operation of onsite sewage treatment systems. Even a properly functioning soil absorption system is only capable of removing phosphorus and microorganisms. The nitrogen remaining after plant uptake will not be retained in the soil column, but will instead gradually seep into the groundwater as nitrate. Conditions for nitrogen removal by denitrification are not generally present in a soil absorption bed. Dilution by groundwater is the only treatment available for reducing the nitrogen concentration to specified levels. Therefore based on subsurface conditions, this essentially entails a maximum allowable concentration of septic tanks in a given area. Unfortunately nitrogen is not the only wastewater pollutant of concern. Relatively long survival times and travel distances have been noted for microorganisms originating from soil absorption systems. This is likely to happen if saturated conditions persist under the soil absorption bed or due to surface runoff of effluent as a result of system failure. Soils have a finite capacity for the removal of phosphorus. Once this capacity is exceeded, phosphorus too will seep into the groundwater. The relatively high mobility of phosphorus in sandy soils have been noted in the literature. These issues have serious implications in the design and siting of soil absorption systems. It is not only important to ensure that the system design is based on subsurface conditions but also the density of these systems in given areas is a critical issue. This essentially involves the adoption of a land capability approach to determine the limitations of an individual site for onsite sewage disposal. The most limiting factor at a particular site would determine the overall capability classification for that site which would also dictate the type of effluent disposal method to be adopted.

The effects of dietary fish oil on inflammation, fibrosis and oxidative stress associated with obstructive renal injury in rats.

Scope: We examined whether dietary supplementation with fish oil modulates inflammation, fibrosis and oxidative stress following obstructive renal injury. Methods and results: Three groups of Sprague-Dawley rats (n = 16 per group) were fed for 4 wk on normal rat chow (oleic acid), chow containing fish oil (33 g eicosapentaenoic acid and 26 g docosahexaenoic acid per kg diet), or chow containing safflower oil (60 g linoleic acid per kg diet). All diets contained 7% fat. After 4 wk, the rats were further subdivided into four smaller groups (n = 4 per group). Unilateral ureteral obstruction was induced in three groups (for 4, 7 and 14 days). The fourth group for each diet did not undergo surgery, and was sacrificed as controls at 14 days. When rats were sacrificed, plasma and portions of the kidneys were removed and frozen; other portions of kidney tissue were fixed and prepared for histology. Compared with normal chow and safflower oil, fish oil attenuated collagen deposition, macrophage infiltration, TGF-beta expression, apoptosis, and tissue levels of arachidonic acid, MIP-1 alpha, IL-1 beta, MCP-1 and leukotriene B(4). Compared with normal chow, fish oil increased the expression of HO-1 protein in kidney tissue. Conclusions: Fish oil intake reduced inflammation, fibrosis and oxidative stress following obstructive renal injury.

Basic education for offenders

ILLITERACY is now increasingly recognised as a serious social problem. UNESCO defines literacy in the following way :- "A person is literate when he has acquired the essential knowledge skills that enable him to engage in all those activities in which literacy is required for effective functioning in his group and community" This is in fact seeing the problem in terms of functional literacy. As the demands of an increasingly industrial society grow, more and more people who are functionally illiterate are appearing. Many do not have the functional skills required to enable them to apply for a job. This inability to obtain work is common among clients of the probation service. Literacy has become so important in our society, that to be unable to read and write causes great feeling of isolation, of being different and inferior, which often leads the illiterate to join a group where this deficiency is unknown and where he can gain some status. This is often a delinquent group.

The use of computerised simulators for training of transthoracic and transoesophageal echocardiography. The future of echocardiographic training?

Echocardiography is the commonest form of non-invasive cardiac imaging and is fundamental to patient management. However, due to its methodology, it is also operator dependent. There are well defined pathways in training and ongoing accreditation to achieve and maintain competency. To satisfy these requirements, significant time has to be dedicated to scanning patients, often in the time pressured clinical environment. Alternative, computer based training methods are being considered to augment echocardiographic training. Numerous advances in technology have resulted in the development of interactive programmes and simulators to teach trainees the skills to perform particular procedures, including transthoracic and transoesophageal echocardiography. 82 sonographers and TOE proceduralists utilised an echocardiographic simulator and assessed its utility using defined criteria. 40 trainee sonographers assessed the simulator and were taught how to obtain an apical 2 chamber (A2C) view and image the superior vena cava (SVC). 100% and 88% found the simulator useful in obtaining the SVC or A2C view respectively. All users found it easy to use and the majority found it helped with image acquisition and interpretation. 42 attendees of a TOE training day utilising the simulator assessed the simulator with 100% finding it easy to use, as well as the augmented reality graphics benefiting image acquisition. 90% felt that it was realistic. This study revealed that both trainee sonographers and TOE proceduralists found the simulation process was realistic, helped in image acquisition and improved assessment of spatial relationships. Echocardiographic simulators may play an important role in the future training of echocardiographic skills.

An interactive and adaptive building layer : strategies for allowing people to become advanced building-users

This paper reports outcomes of a pilot study to develop a conceptual framework to allow people to retrofit a building-layer to gain better control of their own built- environments. The study was initiated by the realisation that discussions surrounding the improvement of building performances tend to be about top-down technological solutions rather than to help and encourage bottom-up involvement of building-users. While users are the ultimate beneficiaries and their feedback is always appreciated, their direct involvements in managing buildings would often be regarded as obstruction or distraction. This is largely because casual interventions by uninformed building-users tend to disrupt the system. Some earlier researches showed however that direct and active participation of users could improve the building performance if appropriate training and/or systems were introduced. We also speculate this in long run would also make the built environment more sustainable. With this in mind, we looked for opportunities to retrofit our own office with an interactive layer to study how we could introduce ad-hoc systems for building-users. The aim of this paper is to describe our vision and initial attempts followed by discussion.