Non-nulling protocols for fast, accurate, 3-D velocity measurements in stacks.

The authors present protocols for making fast, accurate, 3D velocity measurements in the stacks of coal-fired power plants. The measurements are traceable to internationally-recognized standards; therefore, they provide a rigorous basis for measuring and/or regulating the emissions from stacks. The authors used novel, five-hole, hemispherical, differential-pressure probes optimized for non-nulling (no-probe rotation) measurements. The probes resist plugging from ash and water droplets. Integrating the differential pressures for only 5 seconds determined the axial velocity Va with an expanded relative uncertainty Ur(Va) ≤ 2% of the axial velocity at the probe's location, the flow's pitch (α) and yaw (ß) angles with expanded uncertainties U(α) = U(ß) = 1 °, and the static pressure ps with Ur(ps) = 0.1% of the static pressure. This accuracy was achieved 1) by calibrating each probe in a wind tunnel at 130, strategically-chosen values of (Va, α, ß) spanning the conditions found in the majority of stacks (|α| ≤ 20 °; |ß| ≤ 40 °; 4.5 m/s ≤ Va ≤27 m/s), and 2) by using a long-forgotten definition of the pseudo-dynamic pressure that scales with the dynamic pressure. The resulting calibration functions span the probe-diameter Reynolds number range from 7,600 to 45,000.Implications: The continuous emissions monitoring systems (CEMS) that measure the flue gas flow rate in coal-fired power plant smokestacks are calibrated (at least) annually by a velocity profiling method. The stack axial velocity profile is measured by traversing S-type pitot probes (or one of the other EPA-sanctioned pitot probes) across two orthogonal, diametric chords in the stack cross-section. The average area-weighted axial velocity calculated from the pitot traverse quantifies the accuracy of the CEMS flow monitor. Therefore, the flow measurement accuracy of coal-fired power plants greenhouse gas (GHG) emissions depends on the accuracy of pitot probe velocity measurements. Coal-fired power plants overwhelmingly calibrate CEMS flow monitors using S-type pitot probes. Almost always, stack testers measure the velocity without rotating or nulling the probe (i.e., the non-nulling method). These 1D non-nulling velocity measurements take significantly less time than the corresponding 2D nulling measurements (or 3D nulling measurements for other probe types). However, the accuracy of the 1D non-nulling velocity measurements made using S-type probes depends on the pitch and yaw angles of the flow. Measured axial velocities are accurate at pitch and yaw angles near zero, but the accuracy degrades at larger pitch and yaw angles.The authors developed a 5-hole hemispherical pitot probe that accurately measures the velocity vector in coal-fired smokestacks without needing to rotate or null the probe. This non-nulling, 3D probe is designed with large diameter pressure ports to prevent water droplets (or particulates) from obstructing its pressure ports when applied in stack flow measurement applications. This manuscript presents a wind tunnel calibration procedure to determine the non-nulling calibration curves for 1) dynamic pressure; 2) pitch angle; 3) yaw angle; and 4) static pressure. These calibration curves are used to determine axial velocities from 6 m/s to 27 m/s, yaw angles between ±40°, and pitch angles between ±20°. The uncertainties at the 95% confidence limit for axial velocity, yaw angle, and pitch angle are 2% (or less), 1°, and 1°, respectively. Therefore, in contrast to existing EPA-sanctioned probes, the non-nulling hemispherical probe provides fast, low uncertainty velocity measurements independent of the pitch and yaw angles of the stack flow.

The experience of sensorimotor integration of a lower limb sensory neuroprosthesis: A qualitative case study.

Introduction: Lower limb prosthesis users often struggle to navigate uneven terrain or ambulate in low light conditions where it can be challenging to rely on visual cues for balance and walking. Sensory feedback about foot-floor interactions may allow users to reduce reliance on secondary sensory cues and improve confidence and speed when navigating difficult terrain. Our group has developed a Sensory Neuroprosthesis (SNP) to restore sensation to people with lower limb amputation by pairing electrical stimulation of nerves in the residual limb applied via implanted neurotechnology with pressure sensors in the insole of a standard prosthesis. Stimulation applied to the nerves evoked sensations perceived as originating on the missing leg and foot. Methods: This qualitative case study reports on the experiences of a 68-year-old with a unilateral trans-tibial amputation who autonomously used the SNP at home for 31 weeks. Interview data collected throughout the study period was analyzed using a grounded theory approach with constant comparative methods to understand his experience with this novel technology and its impacts on his daily life. Results: A conceptual model was developed that explained the experience of integrating SNP-provided sensory feedback into his body and motor plans. The model described the requirements of integration, which were a combination of a low level of mental focus and low stimulation levels. While higher levels of stimulation and focus could result in distinct sensory percepts and various phantom limb experiences, optimal integration was associated with SNP-evoked sensation that was not readily perceivable. Successful sensorimotor integration of the SNP resulted in improvements to locomotion, a return to a more normal state, an enhancement of perceived prosthesis utility, and a positive outlook on the experience. Discussion: These outcomes emerged over the course of the nearly 8 month study, suggesting that findings from long-term home studies of SNPs may differ from those of short-term in-laboratory tests. Our findings on the experience of sensorimotor integration of the SNP have implications for the optimal training of SNP users and the future deployment of clinical SNP systems for long-term home use.

Cell proliferation detected using [18F]FLT PET/CT as an early marker of abdominal aortic aneurysm.

BACKGROUND: Abdominal aortic aneurysm (AAA) is a focal aortic dilatation progressing towards rupture. Non-invasive AAA-associated cell proliferation biomarkers are not yet established. We investigated the feasibility of the cell proliferation radiotracer, fluorine-18-fluorothymidine ([18F]FLT) with positron emission tomography/computed tomography (PET/CT) in a progressive pre-clinical AAA model (angiotensin II, AngII infusion). METHODS AND RESULTS: Fourteen-week-old apolipoprotein E-knockout (ApoE-/-) mice received saline or AngII via osmotic mini-pumps for 14 (n = 7 and 5, respectively) or 28 (n = 3 and 4, respectively) days and underwent 90-minute dynamic [18F]FLT PET/CT. Organs were harvested from independent cohorts for gamma counting, ultrasound scanning, and western blotting. [18F]FLT uptake was significantly greater in 14- (n = 5) and 28-day (n = 3) AAA than in saline control aortae (n = 5) (P < 0.001), which reduced between days 14 and 28. Whole-organ gamma counting confirmed greater [18F]FLT uptake in 14-day AAA (n = 9) compared to saline-infused aortae (n = 4) (P < 0.05), correlating positively with aortic volume (r = 0.71, P < 0.01). Fourteen-day AAA tissue showed increased expression of thymidine kinase-1, equilibrative nucleoside transporter (ENT)-1, ENT-2, concentrative nucleoside transporter (CNT)-1, and CNT-3 than 28-day AAA and saline control tissues (n = 3 each) (all P < 0.001). CONCLUSIONS: [18F]FLT uptake is increased during the active growth phase of the AAA model compared to saline control mice and late-stage AAA.

Lameness in dairy cows: farmer perceptions and automated detection technology.

This Research Reflection provides an overview of three interrelated topics: (i) lameness in dairy cows, demonstrating the underpinning importance of the condition, (ii) dairy farmer detection, diagnosis and treatment of lameness and associated foot lesions as well as dairy farmer perceptions towards the condition and (iii) lameness detection technologies, and their potential application on farm to automate the detection of lameness in commercial dairy herds. The presented literature clearly demonstrates that lameness is a major health issue in dairy herds, compromising dairy cow welfare and productivity, and resulting in significant economic implications for dairy farmers. Despite this, dairy farmers fail to perceive lameness as a serious threat to their dairy business. This restricted perception of the importance of lameness may be a product of limited ability to detect lame cows. Many automated lameness detection technologies have been proposed to assist dairy farmers in managing their herds. However, limitations such as cost, performance and dairy farmer perception of the usefulness of these technologies, has lead to poor uptake. It can, therefore, be concluded that there is a need to more thoroughly evaluate the effectiveness of these technologies under on-farm conditions, potentially in the form of a demonstration farm network. This will allow generation of the necessary data required to show dairy farmers that these technologies are reliable and are economically rational for their dairy business.

Sharing Ideas and Practice: Institutional Partnership Influences Change in Approaches to Teaching to Enhance Veterinary Education in Vietnam in Conjunction with an OIE Veterinary Education Twinning Project.

A World Organisation for Animal Health (OIE) Veterinary Education Twinning Project was established between the veterinary schools at Nong Lam University (NLU) in Ho Chi Minh City, Vietnam, and the University of Queensland, Gatton, Australia, as part of the scheme established to promote high-quality veterinary services through improved veterinary education. Included in the partnership's primary aims were building the capacity of veterinary teaching staff with respect to general teaching practice and also in response to identified deficiency areas, and to develop outcome assessment processes. One challenge facing the project was the different approaches and experiences of teaching and learning for the faculty and students between the two widely different historical and cultural contexts of Australia and Vietnam. The project enhanced the pedagogy capability in NLU faculty and introduced student-focused approaches to teaching. The NLU staff involved in the project strongly embraced a student-centered approach to learning and case-based teaching in particular, adopting these strategies in their own teaching. An analysis of students' approach to learning demonstrates that the majority preferred a deep approach to learning and that these students valued case studies, problem-solving exercises, and working in small groups during teaching sessions more than students who took a surface approach to learning. An improved recognition of the ways the Vietnamese students approach their learning in their home country will guide future teaching design, as well as give insight into the approaches to teaching for Southeast Asian students within the Australian veterinary science programs.

Understanding dairy farmer intentions to make improvements to their management practices of foot lesions causing lameness in dairy cows.

Foot lesions causing lameness in dairy cows have been demonstrated to adversely affect milk yield, reproductive performance and longevity, resulting in significant economic burden to individual dairy farmers and the dairy industry. Further, foot lesions compromise dairy cow welfare. Despite this knowledge, foot lesions remain a large problem in many dairy herds woldwide. Therefore, there is potential for dairy farmers to make changes to their current management practices of foot lesions. This study used the social-psychology framework, the Theory of Planned Behavior (TPB), to explore dairy farmers' intentions to make improvements to their current management practices of foot lesions in their dairy cows and to identify the underlying behavioral, normative and control beliefs facilitating and constraining this behavior. In accordance with the theoretical framework, Australian dairy farmers were invited to participate in an online questionnaire which included questions regarding intentions, attitudes, subjective norms and perceived behavioral control. Fifty-six dairy farmers completed the questionnaire. The overall intention of these dairy farmers to make improvements to their management practices of foot lesions in the next year was moderate. Dairy farmers believed improving their current management practices of foot lesions would improve animal welfare, increase milk production and was worth the cost involved (behavioral beliefs). They indicated that the opinions of consumers, staff, and animal welfare groups were important in their decision to make improvements (normative beliefs). Better equipment and facilities, improved knowledge and training, and a favorable cost-benefit ratio were perceived as factors that would enable dairy farmers to improve their management practices (control beliefs). While all of these beliefs may be considered as potential drivers to facilitate dairy farmers to change their management practices, the behavioral beliefs were identified as the priority beliefs that industry should target in the development of strategies to increase dairy farmer intentions to make improvements to their management practices of foot lesions.

A well-tolerated and rapidly acting thiopurine for IBD?

Thiopurine drugs continue to be a cornerstone of inflammatory bowel disease (IBD) treatment. Thiopurines are economical compared with many newer medical treatments for IBD, other chronic inflammatory diseases and leukaemia, although they are not without their shortcomings. These include a slow-onset therapeutic action and many adverse drug reactions. This feature article surveys published data, unpublished in vitro and in vivo experiments, as well as clinical experience, underpinning a rationale for bringing a novel thiopurine drug formulation to market. This formulation has a rapid action making it suitable for the induction and maintenance treatment of IBD and avoids most thiopurine-associated adverse reactions.

A factor analytic investigation of the Mercy Evaluation of Multiple Sclerosis.

OBJECTIVE: Neurocognitive deficits commonly are an accompanying feature of Multiple Sclerosis (MS). A brief, yet comprehensive neuropsychological battery is desirable for assessing the extent of these deficits. Therefore, the present study examined the validity of the Mercy Evaluation of Multiple Sclerosis (MEMS) for use with the MS population. METHODS: Archival data from individuals diagnosed with MS (N = 378) by independent neurologists was examined. Cognitive domains assessed included processing speed and attention, learning, and memory, visuospatial, language, and executive functioning. A mean battery index was calculated to provide a general indicator of cognitive impairment within the current sample. RESULTS: Overall performance across participants was found to be in the lower limits of the average range. Results of factor analytic statistical procedures yielded a four-factor solution, accounting for 67% of total variance within the MEMS. Four neurocognitive measures exhibited the highest sensitivity in detecting cognitive impairment, constituting a psychometrically established brief cognitive screening battery, which accounted for 83% of total variance within the mean battery index score. CONCLUSION: Overall, the results of the current study suggest appropriate construct validity of the MEMS for use with individuals with MS, as well as provide support for previously established cognitive batteries.

A systematic review of tests for the detection and diagnosis of foot lesions causing lameness in dairy cows.

Foot lesions causing lameness in dairy cows are important economic and welfare issues. Prompt and correct detection and diagnosis are critical for improving economic and welfare outcomes. Few tests are currently available to aid the dairy farmer in the detection and diagnosis of foot lesions. The objectives of this systematic review were to identify those tests that have been investigated for the detection and diagnosis of foot lesions causing lameness in dairy cows, evaluate the methodological quality of the studies investigating the identified tests, compare the accuracy of the identified test, and determine which tests can be recommended for implementation on the farm based on accuracy and practicality for use by dairy farmers. A comprehensive literature search resulted in 2137 papers. After removing duplicates and performing relevance screening, 12 papers with 20 studies met the inclusion criteria. Pertinent data from each study were extracted using a standardised form. Eligible studies were grouped based on the objective of the test under investigation, resulting in the following groups of disorders: lameness, foot lesions, sole ulcer, and digital dermatitis. Methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool which includes four domains: animal selection, index test, reference test and flow and timing. Incomplete reporting in the studies limited the assessment of methodological quality. The animal selection domain was particularly poorly reported. No single study could be classified as being at low risk of bias across all domains of the QUADAS-2 tool. One automated test was identified, while all others were manually operated. No studies reported the cost of the test in question and only two studies reported the time taken to carry out the procedures involved with using the test in question. It was not possible to compare the accuracy of these tests or recommend which tests are suitable for implementation on the farm. This was due to incomplete reporting of information and significant risk of bias in all studies.

Examination of the Construct Validity of the Repeatable Battery for the Assessment of Neuropsychological Status Language Index in a Mixed Neurological Sample.

OBJECTIVE: We sought to examine the construct validity of the Language Index of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). METHODS: Archival neuropsychological data were collected for 2,057 individuals of diverse neurological etiologies. RESULTS: Correlations were seen between the RBANS Language Index and its indices (Semantic Fluency r = .727; Picture Naming r = .786), between Semantic Fluency and both Category Fluency (r = .379) and the Controlled Oral Word Association test (r = .375), and between Picture Naming and both Visual Naming from the Multilingual Aphasia Examination (r = .447) and the Boston Naming Test (r = .519). Finally, Picture Naming predicted performance on both Visual Naming [F(1,495) = 123.36, p < .000] and the Boston Naming Test [F(1,262) = 96.28, p < .000]. CONCLUSION: Given these results, support for the interpretation of RBANS Language Index appears warranted in a diverse clinical sample.

An updated method for the jugular catheterization of grower pigs for repeated blood sampling following an oral glucose tolerance test.

Jugular catheterization is a common procedure used under experimental conditions. However, there is considerable variation in the reported techniques, particularly for grower pigs (>40 kg and <60 kg) when larger volumes of blood per sample (>10 mL) are required. This paper provides a complete methodology including the use of current equipment and anaesthetic regimen for grower pigs. This surgical jugular catheterization method was carried out in 30 large white grower pigs. Firstly, the pigs were habituated to human handling for at least two weeks prior to surgery. Animals were sedated and anesthetized. Following intubation, an incision was made in the jugular fossa, and the jugular vein was located. A catheter was then inserted and fixated. The wound was stapled and the catheter line secured to the back of the neck. The pigs recovered fully from the surgery and the catheters remained patent for the duration of the blood sampling period (min 72 h). Twenty millilitres of blood were collected every 15 min, taking approximately 2 min per pig. No haemolysis was detected in any samples. Jugular catheterization of pigs using this procedure proved successful both in terms of animal recovery and quality of samples. Catheters remained patent and pigs remained calm during sampling.

Long Receptor Residence Time of C26 Contributes to Super Agonist Activity at the Human ß2 Adrenoceptor.

Super agonists produce greater functional responses than endogenous agonists in the same assay, and their unique pharmacology is the subject of increasing interest and debate. We propose that receptor residence time and the duration of receptor signaling contribute to the pharmacology of super agonism. We have further characterized the novel ß2 adrenoceptor agonist C26 (7-[(R)-2-((1R,2R)-2-benzyloxycyclopentylamino)-1-hydroxyethyl]-4-hydroxybenzothiazolone), which displays higher intrinsic activity than the endogenous ligand adrenaline in cAMP accumulation, ß-arrestin-2 recruitment, and receptor internalization assays. C26 recruited ß-arrestin-2, and internalized the Green Fluorescent Protein (GFP)-taggedß2 adrenoceptor at a slow rate, with half-life (t1/2) values of 0.78 ± 0.1 and 0.78 ± 0.04 hours, respectively. This was compared with 0.31 ± 0.04 and 0.34 ± 0.01 hours for adrenaline-mediated ß-arrestin-2 recruitment and GFP-ß2 internalization, respectively. The slower rate for C26 resulted in levels of ß-arrestin-2 recruitment increasing up to 4-hour agonist incubation, at which point the intrinsic activity was determined to be 124.3 ± 0.77% of the adrenaline response. In addition to slow functional kinetics, C26 displayed high affinity with extremely slow receptor dissociation kinetics, giving a receptor residence half-life of 32.7 minutes at 37°C, which represents the slowest dissociation rate we have observed for any ß2 adrenoceptor agonist tested to date. In conclusion, we propose that the gradual accumulation of long-lived active receptor complexes contributes to the increased intrinsic activity of C26 over time. This highlights the need to consider the temporal aspects of agonist binding and signaling when characterizing ligands as super agonists.

The effect of premorbid attention-deficit/hyperactivity disorder on neuropsychological functioning in individuals with acute mild traumatic brain injuries.

INTRODUCTION: Mild traumatic brain injury (mTBI) is a frequent, yet undertreated condition that typically manifests with transient neurological and cognitive symptoms that resolve over the course of several weeks. In contrast, attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that presents initially in childhood but often persists into adulthood. mTBI and ADHD include overlapping symptomatology, making it difficult for clinicians to disentangle the sequelae of each condition when they co-occur in the same individual. We hypothesized that neuropsychological tests would be sensitive to preexisting ADHD in inpatients with acute mTBIs. METHOD: We retrospectively examined the medical charts of 100 inpatients, aged 18-40 years (96% Caucasian; 77% male) with mTBIs in an acute care setting, half of whom had self-reported the presence of premorbid ADHD, and half of whom were matched controls. We analyzed group differences across neuropsychological tests of attention, processing speed, and executive functions, examined the profile ratings of independent, blinded, board-certified neuropsychologists, and correlated cognitive performance with time from traumatic injury to testing. RESULTS: Individuals with premorbid ADHD (a) performed significantly worse than their matched counterparts on several tests of attention, processing speed, and working memory, and (b) were significantly more likely to produce profiles later rated as impaired by independent, board-certified clinical neuropsychologists. In addition, time from traumatic injury to testing was found to be negatively correlated with neurocognitive performance. CONCLUSIONS: These findings (a) argue for the utility of a brief assessment of premorbid ADHD in the acute care of individuals with mTBIs and (b) provide clinicians with a barometer for gauging the relative contributions of premorbid ADHD to neuropsychological impairments in the neurocognitive profiles of individuals with mTBIs. Reported effect sizes will assist clinicians in accurately weighing the impact of premorbid ADHD when interpreting such profiles.

Hydrogen Field Test Standard: Laboratory and Field Performance.

The National Institute of Standards and Technology (NIST) developed a prototype field test standard (FTS) that incorporates three test methods that could be used by state weights and measures inspectors to periodically verify the accuracy of retail hydrogen dispensers, much as gasoline dispensers are tested today. The three field test methods are: 1) gravimetric, 2) Pressure, Volume, Temperature (PVT), and 3) master meter. The FTS was tested in NIST's Transient Flow Facility with helium gas and in the field at a hydrogen dispenser location. All three methods agree within 0.57 % and 1.53 % for all test drafts of helium gas in the laboratory setting and of hydrogen gas in the field, respectively. The time required to perform six test drafts is similar for all three methods, ranging from 6 h for the gravimetric and master meter methods to 8 h for the PVT method. The laboratory tests show that 1) it is critical to wait for thermal equilibrium to achieve density measurements in the FTS that meet the desired uncertainty requirements for the PVT and master meter methods; in general, we found a wait time of 20 minutes introduces errors < 0.1 % and < 0.04 % in the PVT and master meter methods, respectively and 2) buoyancy corrections are important for the lowest uncertainty gravimetric measurements. The field tests show that sensor drift can become a largest component of uncertainty that is not present in the laboratory setting. The scale was calibrated after it was set up at the field location. Checks of the calibration throughout testing showed drift of 0.031 %. Calibration of the master meter and the pressure sensors prior to travel to the field location and upon return showed significant drifts in their calibrations; 0.14 % and up to 1.7 %, respectively. This highlights the need for better sensor selection and/or more robust sensor testing prior to putting into field service. All three test methods are capable of being successfully performed in the field and give equivalent answers if proper sensors without drift are used.

Comparative quantitative monitoring of rabbit haemorrhagic disease viruses in rabbit kittens.

BACKGROUND: Only one strain (the Czech CAPM-v351) of rabbit haemorrhagic disease virus (RHDV) has been released in Australia and New Zealand to control pest populations of the European rabbit O. cuniculus. Antigenic variants of RHDV known as RHDVa strains are reportedly replacing RHDV strains in other parts of the world, and Australia is currently investigating the usefulness of RHDVa to complement rabbit biocontrol efforts in Australia and New Zealand. RHDV efficiently kills adult rabbits but not rabbit kittens, which are more resistant to RHD the younger they are and which may carry the virus without signs of disease for prolonged periods. These different infection patterns in young rabbits may significantly influence RHDV epidemiology in the field and hence attempts to control rabbit numbers. METHODS: We quantified RHDV replication and shedding in 4-5 week old rabbits using quantitative real time PCR to assess their potential to shape RHDV epidemiology by shedding and transmitting virus. We further compared RHDV-v351 with an antigenic variant strain of RHDVa in kittens that is currently being considered as a potential RHDV strain for future release to improve rabbit biocontrol in Australia. RESULTS: Kittens were susceptible to infection with virus doses as low as 10 ID50. Virus growth, shedding and transmission after RHDVa infection was found to be comparable or non-significantly lower compared to RHDV. Virus replication and shedding was observed in all kittens infected, but was low in comparison to adult rabbits. Both viruses were shed and transmitted to bystander rabbits. While blood titres indicated that 4-5 week old kittens mostly clear the infection even in the absence of maternal antibodies, virus titres in liver, spleen and mesenteric lymph node were still high on day 5 post infection. CONCLUSIONS: Rabbit kittens are susceptible to infection with very low doses of RHDV, and can transmit virus before they seroconvert. They may therefore play an important role in RHDV field epidemiology, in particular for virus transmission within social groups during virus outbreaks.

Novel impedimetric immunosensor for detection of pathogenic bacteria Streptococcus pyogenes in human saliva.

Streptococcus pyogenes , also known as group A streptococcus (GAS), is a Gram positive human pathogen responsible for invasive and noninvasive human infections with a high incidence rate. Traditional detection methods involve cell culture and PCR, which are limited by long processing times or the need for high cost equipment. Impedance-based electrochemical immunosensors provide an alternative by which precise and rapid quantitative detection of the organism can help with rapid clinical decisions. To bring a biosensor for point-of-care applications to market, strict optimization of each level of construction and operation is required. In this paper, commercial screen-printed gold electrodes have been used to construct polytyramine (Ptyr)-based immunosensors. Biotin tagged whole antibodies against S. pyogenes were conjugated to Ptyr amine group via biotin-NeutrAvidin coupling. Sensors were optimized at each level of construction, particularly for Ptyr electrodeposition and antibody concentration, to optimize signal and specificity. Scanning electron microscopy, fluorescence microscopy, and on-sensor analysis (HRP conjugated enhanced chemiluminescence-based semiquantitative method) to detect Ptyr surface amine and bound antibody were performed as supporting techniques. Cumulative and single shot incubations had shown detection range of 100 to 10(5) cells per 10 µL and 100 to 10(4) cells per 10 µL of bacteria in PBS, respectively. Sensors were also able to specifically detect S. pyogenes in 50% (v/v) human saliva, with good selectivity and low cross-reactivity.

The non-pathogenic Australian rabbit calicivirus RCV-A1 provides temporal and partial cross protection to lethal Rabbit Haemorrhagic Disease Virus infection which is not dependent on antibody titres.

The endemic non-pathogenic Australian rabbit calicivirus RCV-A1 is known to provide some cross protection to lethal infection with the closely related Rabbit Haemorrhagic Disease Virus (RHDV). Despite its obvious negative impacts on viral biocontrol of introduced European rabbits in Australia, little is known about the extent and mechanisms of this cross protection. In this study 46 rabbits from a colony naturally infected with RCV-A1 were exposed to RHDV. Survival rates and survival times did not correlate with titres of serum antibodies specific to RCV-A1 or cross reacting to RHDV, but were instead influenced by the time between infection with the two viruses, demonstrating for the first time that the cross protection to lethal RHDV infection is transient. These findings are an important step towards a better understanding of the complex interactions of co-occurring pathogenic and non-pathogenic lagoviruses.

Serological assays to discriminate rabbit haemorrhagic disease virus from Australian non-pathogenic rabbit calicivirus.

Serological cross reactivity between the virulent rabbit haemorrhagic disease virus (RHDV) and the closely related but non-pathogenic rabbit calicivirus (RCV) makes it difficult to study the epidemiology of each virus and the interaction between them when both viruses co-circulate in wild rabbit populations. ELISA methods for the diagnosis of RHDV infection are well characterized, but no specific serological tests for RCV have been developed. Following the characterization of Australian non-pathogenic RCV-A1 strains, we used virus-like-particles (VLPs) and anti-RCV-A1 specific antibodies to establish a set of isotype ELISAs for detection of IgG, IgA and IgM in rabbit sera and secretory mucosal IgA in rectal swabs, and two competition ELISAs. These assays were used to discriminate between anti-RCV-A1 and anti-RHDV antibodies in rabbits. The isotype ELISAs were highly sensitive for detection of anti-RCV-A1 antibodies, but varying levels of cross reactivity from anti-RHDV antibodies occurred in the isotype ELISAs and one competition ELISA. However, the second competition ELISA specifically detected antibodies to RCV-A1 and showed no cross reactivity to anti-RHDV sera. These ELISAs provide important tools to monitor RCV-A1 infection when it occurs alone, and to discriminate between RHDV and RCV-A1 infection when they occur in the same rabbit population. When used in parallel with RHDV serology, they could be used to monitor the dynamics of these two closely related but pathogenically distinct viruses in wild and domestic rabbit populations.

Lipoblastomatosis: case report and review of the literature.

PURPOSE: To describe an unusual presentation of lipoblastomatosis and review the existing literature on lipoblastomatosis and lipoblastoma. METHODS: Case report and literature review. RESULTS: A 9-year-old girl was originally diagnosed as having preseptal cellulitis. After failure of systemic therapy, a CT scan showed a mass in the orbit. Biopsy of the lesion confirmed the presence of lipoblastomatosis, consisting of immature lipoblasts admixed with more-mature adipocytes. CONCLUSIONS: Lipoblastomatosis is a rare benign diffuse lipomatous tumor of embryonal fat that is uncommonly found in the head and face of children.