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The toxicity of oil sands process-affected water (OSPW) has regularly been attributed to naphthenic acids, which exist in complex mixtures. If on remediation treatment (e.g., ozonation) or on entering the environment, the mixtures of these acids all behave in the same way, then they can be studied as a whole. If, however, some acids are resistant to change, whilst others are not, or are less resistant, it is important to establish which sub-classes of acids are the most toxic.In the present study we therefore assayed the acute toxicity to larval fish, of a whole acidified OSPW extract and an esterifiable naphthenic acids fraction, de-esterified with alkali: both fractions were toxic (LC50 ~5-8mgL-1). We then fractionated the acids by argentation solid phase extraction of the esters and examined the acute toxicity of two fractions: a de-esterified alicyclic acids fraction, which contained, for example, adamantane and diamantane carboxylic acids, and an aromatic acids fraction. The alicyclic acids were toxic (LC50 13mgL-1) but the higher molecular weight aromatic acids fraction was somewhat more toxic, at least on a weight per volume basis (LC50 8mgL-1; P<0.05) (for comparison, the monoaromatic dehydroabietic acid had a LC50 of ~1mgL-1).These results show how toxic naphthenic acids of OSPW are to these larval fish and that on a weight per volume basis, the aromatic acids are at least as toxic as the 'classical' alicyclic acids. The environmental fates and other toxic effects, if any, of the fractions remain to be established. © 2013 Elsevier Ltd.

Process waters from oil sands industries (OSPW) have been reported to exhibit estrogenic effects. Although the compounds responsible are unknown, some aromatic naphthenic acids (NA) have been implicated. The present study was designed to investigate whether aromatic NA might cause such effects. Here we demonstrate induction of vitellogenin genes (vtg) in fish, which is a common bioassay used to indicate effects consistent with exposure to exogenous estrogens. Solutions in water of 20-2000 µg L-1 of an extract of a total OSPW NA concentrate did not induce expression of vtg in larval zebrafish, consistent with earlier studies which showed that much higher NA concentrations of undiluted OSPW were needed. Although 20-2000 µg L-1 of an esterifiable NA subfraction of the OSPW NA concentrate did induce expression, this was of much lower magnitude to that induced by much lower concentrations of 17a-ethynyl estradiol, indicating that the effect of the total NAs was only weak. However, given the high NA concentrations and large volumes of OSPW extant in Canada, it is important to ascertain which of these esterifiable NA in the OSPW produce the effect. Up to 1000 µg L-1 of an OSPW subfraction containing only alicyclic NA, and considered by most authors to be NA sensu stricto, did not produce induction; but, as predicted, 10-1000 µg L-1 of an aromatic NA fraction did. Such effects by the aromatic acids are again consistent with those of only a weak estrogenic substance. These findings may help to focus studies of the most environmentally significant OSPW-related pollutants, if reproduced in a greater range of OSPW. © 2013 American Chemical Society.

Background: Practical hands-on learning opportunities are viewed as a vital component of the education of health science students, but there is a critical shortage of fieldwork placement experiences. It is therefore important that these clinical learning environments are well suited to students' perceptions and expectations. Purpose(s): To investigate how undergraduate students enrolled in health-related education programs view their clinical learning environments and specifically to compare students' perception of their 'actual' clinical learning environment to that of their 'preferred/ideal' clinical learning environment. Method(s): The Clinical Learning Environment Inventory (CLEI) was used to collect data from 548 undergraduate students (55% response rate) enrolled in all year levels of paramedics, midwifery, radiography and medical imaging, occupational therapy, pharmacy, nutrition and dietetics, physiotherapy and social work at Monash University via convenience sampling. Students were asked to rate their perception of the clinical learning environment at the completion of their placements using the CLEI. Result(s): Satisfaction of the students enrolled in the health-related disciplines was closely linked with the five constructs measured by the CLEI: Personalization, Student Involvement, Task Orientation, Innovation, and Individualization. Significant differences were found between the student's perception of their 'actual' clinical learning environment and their 'ideal' clinical learning environment. Conclusion(s): The study highlights the importance of a supportive clinical learning environment that places emphasis on effective two-way communication. A thorough understanding of students' perceptions of their clinical learning environments is essential. © 2010 Elsevier Ltd.

The large volumes, acute toxicity, estrogenicity, and antiandrogenicity of process-affected waters accruing in tailings ponds from the operations of the Alberta oil sands industries pose a significant task for environmental reclamation. Synchronous fluorescence spectra (SFS) suggest that oil sands process-affected water (OSPW) may contain aromatic carboxylic acids, which are among the potentially environmentally important toxicants, but no such acids have yet been identified, limiting interpretations of the results of estrogenicity and other assays. Here we show that multidimensional comprehensive gas chromatography-mass spectrometry (GCxGC-MS) of methyl esters of acids in an OSPW sample produces mass spectra consistent with their assignment as C 19 and C20 C-ring monoaromatic hydroxy steroid acids, D-ring opened hydroxy and nonhydroxy polyhydrophenanthroic acids with one aromatic and two alicyclic rings and A-ring opened steroidal keto acids. High resolution MS data support the assignment of several of the so-called O3 species. When fractions of distilled, esterified, OSPW acid-extractable organics were examined, the putative aromatics were mainly present in a high boiling fraction; when examined by argentation thin layer chromatography, some were present in a fraction with a retardation factor between that of the methyl esters of synthetic monoalicyclic and monoaromatic acids. Ultraviolet absorption spectra of these fractions indicated the presence of benzenoid moieties. SFS of model octahydro- and tetrahydrophenanthroic acids produced emissions at the characteristic excitation wavelengths observed in some OSPW extracts, consistent with the postulations from ultraviolet spectroscopy and mass spectrometry data. We suggest the acids originate from extensive biodegradation of C-ring monoaromatic steroid hydrocarbons and offer a means of differentiating residues at different biodegradation stages in tailings ponds. Structural similarities with estrone and estradiol im

Objectives: It has been identified that health science student groups may have distinctive learning needs. By university educators' and professional fieldwork supervisors' being aware of the unique learning style preferences of health science students, they have the capacity to adjust their teaching approaches to best fit with their students' learning preferences. The purpose of this study was to investigate the learning style preferences of a group of Australian health science students enrolled in 10 different disciplines. Method(s): The Kolb Learning Style Inventory was distributed to 2,885 students enrolled in dietetics and nutrition, midwifery, nursing, occupational therapy, paramedics, pharmacy, physiotherapy, radiation therapy, radiography, and social work at one Australian university. A total of 752 useable survey forms were returned (response rate 26%). Result(s): The results indicated the converger learning style to be most frequently preferred by health science students and that the diverger and accommodator learning styles were the least preferred. Conclusion(s): It is recommended that educators take learning style preferences of health science students into consideration when planning, implementing, and evaluating teaching activities, such as including more problem-solving activities that fit within the converger learning style.