Cross-validation of standardisation techniques at ANSTO using cobalt-60 and learnings from the presence and identification of non-gamma-ray emitting impurities

To fulfil the technical requirements for accreditation to ISO/IEC 17025, the end-to-end validation of all processes associated with standardising 60Co, including gravimetric source dispensing, primary standardisation by the 4π(LS)β-γ coincidence and live-timed anti-coincidence extrapolation techniques, and impurity determination were performed and documented. Pure-beta-emitting impurities in a 60Co stock solution were identified. The impact of such impurities on measurement by liquid scintillation counting and comparison in the ESIR are discussed. A fresh 60Co source was produced, standardised, and compared using the SIR.

The international reference system for beta-particle emitting radionuclides: Validation through the pilot study CCRI(II)-P1.Co-60

The Bureau International des Poids et Mesures (BIPM) is developing a new transfer instrument to extend its centralized services for assessing the international equivalence of radioactive standards to new radionuclides. A liquid scintillation counter using the triple/double coincidence ratio method is being studied and tested in the CCRI(II)-P1.Co-60 pilot study. The pilot study, involving 13 participating laboratories with primary calibration capabilities, validated the approach against the original international reference system based on ionization chambers, which has been in operation since 1976. The results are in agreement and an accuracy suitable for purpose, below 5×10-4, is achieved. The pilot study also reveals an issue when impurities emitting low-energy electrons are present in the standard solution, which have a different impact on liquid scintillation counting compared to other primary measurement methods.

Sonographic diagnosis of a neonatal gastric perforation presenting with scrotal swelling

Neonatal gastric perforation is a rare, serious and frequently fatal condition of unclear etiology. The most common clinical presentation include tachypnea, respiratory distress, abdominal distension and cyanosis. We report an unusual case of neonatal gastric perforation presenting as erythematous scrotal swelling mimicking testicular torsion. This clinical presentation is unusual and early diagnosis and treatment is essential in order to prevent significant mortality and morbidity.

A preliminary study on normal electrocardiographic parameters of ostriches (Struthio camelus)

Electrocardiograms were taken from 100 normal healthy male and female ostriches which were 1 to 15 months old using a base apex lead. The heart rate of those less than 3 months old ranged from 107 to 250 beats per minute with a mean of 171.47+9.03 and that of ostriches of more than 3 months old ranged from 43 to 167 with a mean of 90.52+2.64 beats / minute. The P-waves were positive in all cases except in 1 ostrich which it was isoelectric. The ORS complexes were mainly negative and either monophasic (QS) or biphasic (rS or RS). The T-wave showed more variation than other waves. The durations of P, P-R, QRS, Q-T and T-waves of chicks and of those more than 3 months of age (4-15-month-old) were 0.04 + 0.00, 0.06+0.00; 0.14+0.04, 0.16+0.00; 0.04+0.00, 0.06+0.00; 0.18+0.00, 0.27+0.00 and 0.06+0.00, 0.09+0.01 s, respectively, and amplitudes of the main direction of P-, QRS and T- waves of 2 groups were 0.29 + 0.02, 0.26 + 0.01; 1.87 + 0.17, 2.21 + 0.08; and 0.34 + 0.06, 0.37 + 0.02 mV, respectively. Ten cases showed cardiac dysrhythmias of which 9 showed sinus arrhythmia and 1 showed premature atrial contractions (PAC). This study showed that the base apex lead can be a suitable monitoring lead for electrocardiographic examination of ostriches.

The clinical perspective of large scale projects: a case study of multiparametric MR imaging of pediatric brain tumors

Current developments in medical information technologies provide the clinical researcher with overwhelming amounts of data that need to be retrieved, organized, analyzed, and shared using secure, efficient, and robust protocols. The development of a local research database can provide an infrastructure for improved data management and detailed data analysis. For example, a pediatric brain tumor database of magnetic resonance imaging data, including conventional MRI imaging, hemodynamic MRI, diffusion weighted MRI and MR spectroscopic imaging, combined with neuropathological and neurological evaluation data, will significantly enhance the assessment and treatment of pediatric brain tumor patients. Furthermore, a negotiation system by which different clinical research facilities can share and combine data will permit re-analyses and meta-analyses of large data arrays that are beyond the focus or time constraints of the original researchers. Such a system will greatly enhance the utility of different data sets to a wide array of scientists. At present, efforts to organize medical data locally and between different sites is limited by diversity, interoperability, security, and accountability difficulties.

Bilateral ureteral involvement in polyarteritis nodosa

A case of polyarteritis nodosa with bilateral ureteral changes in IVU is reported, because of the rarity of ureteric involvement in this entity. The urographic findings were unilateral ureteral stricture with hydronephrosis and irregular ureter outlines bilaterally. All lesions subsided after treatment.