A Principled Complementarity of Method: In Defence of Methodological Eclecticism and the Qualitative-Quantitative Debate

I found PhD study to be a stimulating, challenging and ideal conduit for exploring knowledge via discussion, argument and defence: to have the opportunity to explore method, methodology, epistemology, ontology and what may constitute \u27acceptable\u27 research practice is an enriching experience. I had previously heard of intepretivists decrying positivists et cetera, but I was unprepared to find quantitative researchers and lecturers openly dismissing qualitative approaches, and finding dismissals by qualitative researchers of the use of a quantitative approach: such are disappointing and confusing to a trainee researcher. Thus, a far less enriching experience for a trainee researcher is being faced with assumptions and preferences of experienced researchers that extend from defending approach to decrying any approaches that may not be aligned to their own. As a result, this paper will focus upon the quantitative-qualitative debate (QQD) and offer a critical evaluation upon the issues surrounding affiliations between method and epistemological paradigm. It will also question the validity of \u27traditional\u27 divides between qualitative and quantitative methods. This discussion will facilitate an answer to the question: \u27can the researcher complement quantitative with qualitative method - and vice versa - within the same research paradigm and subsequent design\u27? I will explore here a claim that no more than a rhetorical link exists between method and epistemology and that the \u27distinctions\u27 between quantitative and qualitative methods are often erroneous and do not always reflect differing paradigmatic assumptions. Further, I will suggest quantitative and qualitative methods be used in a complementary fashion as opposed to an integrated approach. I will further claim that the quantitative-qualitative debate has much to offer trainee researchers and should thus be kept open, as long as unprejudiced and tolerant discussion is encouraged

The Use of Bead Beating to Prepare Suspensions of Nuclei for Flow Cytometry from Fresh Leaves, Herbarium Leaves, Petals and Pollen

‘‘Bead beating’’ is commonly used to release DNA from cells for genomic studies but it was used here to prepare suspensions of plant nuclei for measurement of DNA amounts by flow cytometry. Plant material was placed in 2-ml screw-capped tubes containing beads of zirconia/silica (2.5 mm diameter) or glass (2.5 or 1.0 mm diameter) and 1 ml of lysis buffer. The tubes were mechanically shaken with an FP120 FastPrep Cell Disrupter to release intact nuclei from plant tissue by the impact of the beads. The nuclei were then stained with propidium iodide (PI) and analyzed by flow cytometry. The method was tested using fresh leaves, fresh petals and herbarium leaves of Rosa canina, leaves and pollen of R. rugosa, and fresh leaves of Petroselinum crispum, Nicotiana tabacum, and Allium cepa. Batches of 12 samples of fresh leaves were prepared, simultaneously, in 45 s by bead beating in the Cell Disrupter. In flow cytometry histograms, nuclei of fresh leaves gave G1/G0 peaks with CVs of less than 3.0% and nuclei from fresh petals and herbarium leaves of R. canina, and pollen of the generative nuclei of R. rugosa gave peaks with coefficients of variation (CVs) of less than 4.0%. DNA amounts estimated from 24-month-old herbarium leaves, using P. crispum as an internal standard, were less than those of fresh leaves by a small but significant amount. Suspensions of nuclei can be prepared rapidly and conveniently from a diversity of tissues by bead beating. Exposure of laboratory workers to harmful substances in the lysis buffer is minimized

Developmental and reproductive characteristics of beef heifers classified by number of estrous cycles experienced by start of first breeding

A retrospective analysis was conducted to evaluate the effect of number of estrous cycles exhibited before breeding on growth and reproductive performance of replacement beef heifers fed ad-libitum or restricted by 20% less than ad-libitum during postweaning development over a 9-yr period. Progesterone concentration in blood samples collected at 9- to 11-d intervals were used to assign heifers into groups by number of estrous cycles exhibited before the start of breeding: 0 (nonpubertal; n = 395), 1 (n = 205), 2 (n = 211), 3 (n = 116), or \u3e3 (n = 249). Heifers (P \u3c 0.01) in the 0 cycle group were born 6 d later than the 1, 2, or 3 cycle groups, which were born 4 d later (P \u3c 0.01) than the \u3e3 cycle group. Weight of heifers at birth decreased (P \u3c 0.05) as the number of cycles increased. Weaning weight and ultrasound measures of loin area and fat thickness over the loin at 1 yr age increased as the number of cycles increased (P \u3c 0.01). Postwean weight gain, hip height at 1 yr age, and weights from the start of breeding through precalving increased with cycle numbers in a quadratic fashion (P \u3c 0.02) and were greater (P \u3c 0.05) in ad-libitum than restricted-fed heifers. Pregnancy rate in the 0 cycle group was lower (84%; P \u3c 0.05) than the 1 (90%) or \u3e3 (94%) estrous cycles groups and tended to differ (P \u3c 0.1) from the 2 (88%) and 3 (89%) estrous cycle groups. Interval from the start of breeding to calving was 3 to 5 d longer (P \u3c 0.05) for the 0 cycle group (300 ± 1 d) than other groups. Proportion of heifers calving in the first 21 d was less (P \u3c 0.05) in the 0 or 1 cycle groups than other groups. Pregnancy rates of 2-yr-old cows (n = 898) were lowest (P \u3c 0.05) for the 0 (73%) and 2 (79%) estrous cycle groups than the 1 (85%), 3 (90%), or \u3e3 (92%) estrous cycle groups. Restricted level of feeding during postweaning development resulted in greater (P \u3c 0.05) proportion of heifers in 0 cycle group and lower (P \u3c 0.05) proportion in \u3e3 cycle group, but reproductive performance was not influenced (P \u3e 0.1) by level of feeding or interaction of feeding and estrous cycle grouping. In summary, date of birth and rate of physical maturation (weight, height, and fat deposition) were associated with timing of puberty. Pregnancy rate was greater in heifers that exhibited estrus before the start of breeding, but did not improve from having more than one estrous cycle. Proportion conceiving early was greater for heifers having two or more cycles before breeding

An improved method for surface immobilisation of RNA: application to small Non-Coding RNA - mRNA pairing

Characterisation of RNA and its intermolecular interactions is increasing in importance as the inventory of known RNA functions continues to expand. RNA-RNA interactions are central to post-transcriptional gene regulation mechanisms in bacteria, and the interactions of bacterial small non-coding RNAs (sRNAs) with their mRNA targets are the subject of much current research. The technology of surface plasmon resonance (SPR) is an attractive approach to studying these interactions since it is highly sensitive, and allows interaction measurements to be recorded in real-time. Whilst a number of approaches exist to label RNAs for surface-immobilisation, the method documented here is simple, quick, efficient, and utilises the high-affinity streptavidin-biotin interaction. Specifically, we ligate a biotinylated nucleotide to the 3' end of RNA using T4 RNA ligase. Although this is a previously recognised approach, we have optimised the method by our discovery that the incorporation of four or more adenine nucleotides at the 3' end of the RNA (a poly-A-tail) is required in order to achieve high ligation efficiencies. We use this method within the context of investigating small non-coding RNA (sRNA)-mRNA interactions through the application of surface technologies, including quantitative SPR assays. We first focus on validating the method using the recently characterised Escherichia coli sRNA-mRNA pair, MicA-ompA, specifically demonstrating that the addition of the poly-A-tail to either RNA does not affect its subsequent binding interactions with partner molecules. We then apply this method to investigate the novel interactions of a Vibrio cholerae Qrr sRNA with partner mRNAs, hapR and vca0939; RNA-RNA pairings that are important in mediating pathogenic virulence. The calculated binding parameters allow insights to be drawn regarding sRNA-mRNA interaction mechanisms

Karyotypic and 2C nuclear DNA in vitro induced off-types of East African highland banana (Musa AAA East Africa)

This study was conducted to determine chromosome number and 2C nuclear DNA content in tissue culture induced off-type banana (Musa AAA East Africa) landrace Uganda with tolerance black sigatoka disease, susceptibility to water stress, sparsely black-blotched pseudostems, taller pseudostems, late fruit maturation, altered inflorescence and higher fruit dry matter content. The off-type banana appeared to have higher (p<0.05) frequency of 31 and 32 chromosomes at 15.1 and 13.6%, respectively. Conversely, the frequency of 31 and 32 chromosomes was 12.0 and 9.6% for the micropropagation (MP) derived plants with no tissue culture history. Moreover, the off-type banana had lower (p<0.05) leaf 2C nuclear DNA amount of 1.72pg, whilst the MP and CP derived plants had 1.81 pg, respectively

Medical student wellbeing - a consensus statement from Australia and New Zealand

Abstract Background Medical student wellbeing – a consensus statement from Australia and New Zealand outlines recommendations for optimising medical student wellbeing within medical schools in our region. Worldwide, medical schools have responsibilities to respond to concerns about student psychological, social and physical wellbeing, but guidance for medical schools is limited. To address this gap, this statement clarifies key concepts and issues related to wellbeing and provides recommendations for educational program design to promote both learning and student wellbeing. The recommendations focus on student selection; learning, teaching and assessment; learning environment; and staff development. Examples of educational initiatives from the evidence-base are provided, emphasising proactive and preventive approaches to student wellbeing. Main recommendations The consensus statement provides specific recommendations for medical schools to consider at all stages of program design and implementation. These are:Design curricula that promote peer support and progressive levels of challenge to students.Employ strategies to promote positive outcomes from stress and to help others in need.Design assessment tasks to foster wellbeing as well as learning.Provide mental health promotion and suicide prevention initiatives.Provide physical health promotion initiatives.Ensure safe and health-promoting cultures for learning in on-campus and clinical settings.Train staff on student wellbeing and how to manage wellbeing concerns. Conclusion A broad integrated approach to improving student wellbeing within medical school programs is recommended. Medical schools should work cooperatively with student and trainee groups, and partner with clinical services and other training bodies to foster safe practices and cultures. Initiatives should aim to assist students to develop adaptive responses to stressful situations so that graduates are prepared for the realities of the workplace. Multi-institutional, longitudinal collaborative research in Australia and New Zealand is needed to close critical gaps in the evidence needed by medical schools in our region