The development, validation and standardisation of a questionnaire measuring an Auditing teaching-learning intervention at a SAICA-accredited university

Questionnaires are widely used in the Accountancy field as a data collection instrument. However, previous studies have contentious views on the reliability of questionnaires in academic studies. This study describes the development of a custom-made questionnaire to evaluate the effectiveness of a teaching-learning intervention, the Audit Cube, designed to affect the knowledge, skills, attitudes and values of Auditing of B.Com. honours students in the Accountancy field at a SAICA-accredited university. The questionnaire was distributed to 156 university honours students, whereafter it was validated and standardised. Most of the extracted factors indicated a reliability level higher than 0.9, signifying that the constructs were suitable to address the project’s research question and that the questionnaire is valid. In conclusion, this study found that the use of questionnaires in academic studies is deemed reliable if a standardised process is followed in its development. Consequently, the study suggests that custom-made questionnaires should undergo factor analysis to prove the instrument’s validity prior to reporting on the findings. The findings of this study may be useful to academics in providing guidelines in developing their own data collection instrument to measure the effectiveness of a teaching-learning intervention and may also support the use of questionnaires by researchers in the teaching-learning environment

Molecular genetics of cardiomyopathy: changing times, shifting paradigms

The original publication is available at http://www.cvja.co.za/Includes bibliographyCongestive heart failure is a major problem in developed and developing countries alike. Primary dysfunction of the heart muscle accounts for a significant proportion of patients with a non-ischaemic cause of heart failure. Application of genetic techniques has facilitated identification of some molecular causes of the inherited form of these diseases, dramatically increasing our understanding of the pathogenesis of these primary, previously termed ‘idiopathic’, cardiomyopathies over the last few decades. Knowledge of the different causes is beginning to coalesce into aetiological principles underlying the clinically distinguished cardiomyopathies. Hypertrophic cardiomyopathy (HCM) now appears to be a disease caused by a dysfunctional sarcomere, dilated cardiomyopathy (DCM), a disease of myocytic structural instability, and arrhythmogenic right ventricular cardiomyopathy, a disease of accelerated myocyte death. The aetiology of both HCM and DCM probably also involves cardiac energy imbalances, while additional factors modify the clinical expression in all cardiomyopathies. Even though our knowledge of the genetic aetiology of the cardiomyopathies is still incomplete, it already has relevant clinical significance. Elucidation of the full genetic contribution to the development and progression of the cardiomyopathies represents a new challenge in the study of these diseases, and will undoubtedly lead to new therapeutic approaches in the not-too-distant future.Publishers' versio

Stochasticity and homeostasis in the E. coli replication and division cycle

How cells correct for stochasticity to coordinate the chromosome replication and cellular division cycle is poorly understood. We used time-lapse microscopy and fluorescently labelled SeqA to determine the timing of birth, initiation, termination, and division, as well as cell size throughout the cell cycle. We found that the time between birth and initiation (B-period) compensates for stochastic variability in birth size and growth rate. The time between termination and division (D-period) also compensates for size and growth variability, invalidating the notion that replication initiation is the principal trigger for cell division. In contrast, the time between initiation and termination (C-period) did not display such compensations. Interestingly, the C-period did show small but systematic decreases for cells that spontaneously grew faster, which suggests a coupling between metabolic fluctuations and replication. An auto-regressive theoretical framework was employed to compare different possible models of sub-period control

Genetic variation in angiotensin-converting enzyme 2 gene is associated with extent of left ventricular hypertrophy in hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy, a common, inherited cardiac muscle disease, is primarily caused by mutations in sarcomeric protein-encoding genes and is characterized by overgrowth of ventricular muscle that is highly variable in extent and location. This variability has been partially attributed to locus and allelic heterogeneity of the disease-causing gene, but other factors, including unknown genetic factors, also modulate the extent of hypertrophy that develops in response to the defective sarcomeric functioning. Components of the renin-angiotensin-aldosterone system are plausible candidate hypertrophy modifiers because of their role in controlling blood pressure and biological effects on cardiomyocyte hypertrophy

And then there was one: a camera trap survey of the declining population of African elephants in Knysna, South Africa

Conservation agencies rely on accurate wildlife population estimates to inform management practices. The importance of accuracy increases with smaller, threatened populations, but so too does the challenge in achieving it, especially for evasive species in low-visibility terrain. Non-invasive survey techniques have been successfully applied in such conditions; however, each technique bears a unique set of limitations and often deliver different results. The shy Knysna elephants (Loxodonta africana) occur at extremely low numbers in difficult terrain, and the past few decades have seen debates raging about their numbers, fuelled in part by differing survey outcomes, although a decline has been apparent over the last 150 years. We surveyed the known range of the Knysna elephant population for 15 months (July 2016 – October 2017), using camera traps, and identified one adult female elephant. The reliability of using camera trapping for surveying animal populations in conditions such as the Knysna elephant is compared with the previous faecal DNA genotyping survey. We conclude that this population has declined to a single individual and discuss the implications for local conservation authorities. Additionally, we highlight the importance of designing rigorous survey approaches where only a few individual animals are present.The South African National Parks’ (SANParks) Garden Route National Park management teamhttp://www.sawma.co.zahj2020Mammal Research Institut

An in vitro and in vivo study on the properties of hollow polycaprolactone cell-delivery particles

The field of dermal fillers is evolving rapidly and numerous products are currently on the market. Biodegradable polymers such as polycaprolactone (PCL) have been found to be compatible with several body tissues, and this makes them an ideal material for dermal filling purposes. Hollow PCL spheres were developed by the Council for Scientific and Industrial Research (CSIR) to serve both as an anchor point and a ªtissue harbourº for cells. Particles were tested for cytotoxicity and cell adherence using mouse embryo fibroblasts (MEF). MEFs adhered to the particles and no significant toxic effects were observed based on morphology, cell growth, cell viability and cell cycle analysis, suggesting that the particles are suitable candidates for cell delivery systems in an in vivo setting. The objective of providing a ªtissue harbourº was however not realized, as cells did not preferentially migrate into the ported particles. In vivo studies were conducted in BALB/c mice into whom particles were introduced at the level of the hypodermis. Mice injected with PCL particles (ported and nonported; with or without MEFs) showed evidence of local inflammation and increased adipogenesis at the site of injection, as well as a systemic inflammatory response. These effects were also observed in mice that received apparently inert (polystyrene) particles. Ported PCL particles can therefore act as a cell delivery system and through their ability to induce adipogenesis, may also serve as a dermal bulking agent.S1 File. Figure A: Chronic inflammation in the test animals over the trial period. Figure B: Acute inflammation in the test animals over the trial period. Figure C: Tissue necrosis in the test animals over the trial period. Figure D: Fibrosis in the test animals over the trial period. Figure E: Granulomatous/foreign body response in the test animals over the trial period. Figure F: Representative TEMs of skin biopsies of particles group (A) and particles+MEFs group (B) in the in vivo experiment injecting particles+MEFs. Particles could be identified in skin biopsies of both the particles and particles+MEFs groups. The aim of the TEM investigation was to determine if any cells could be detected inside the particles. No cells were present inside the particles in either group. These results reflect the conclusion that was made after the light microscopy study, indicating that cells did not migrate into the ported PCL particles. Bar in A = 5μm and in B = 10μm.S2 File. In vitro and in vivo data. Table A: Groups of rats used in the biotoxicity trial. Table B: Observations on mice in the in vivo experiment assessing the effect of ported PCL particles and cells. Table C: Statistical comparisons preformed between the various white blood cell types assessed from blood smears of experimental mice injected with ported PCL particles with or without MEFs. Table D: Schedule of the in vivo experiment assessing the effect of ported and non-ported PCL as well as polystyrene (PS) particles. Table E: Overview of the animals, tests and procedures performed in the in vivo experiment assessing the effect of ported and non-ported PCL as well as polystyrene (PS) particles in BALB/c mice.S3 File. All data underlying the findings of the study.The Council for Scientific and Industrial Research, South Africa, by the Institute for Cellular and Molecular Medicine of the University of Pretoria and by the South African Medical Research Council (Flagship Award SAMRC-RFA-UFSP-01-2013/ STEM CELLS and the SAMRC Extramural Unit for Stem Cell Research and Therapy).http://www.plosone.orgam2019ImmunologyPhysiolog

Axial distribution of myosin binding protein-C is unaffected by mutations in human cardiac and skeletal muscle

Myosin binding protein-C (MyBP-C), a major thick filament associated sarcomeric protein, plays an important functional and structural role in regulating sarcomere assembly and crossbridge formation. Missing or aberrant MyBP-C proteins (both cardiac and skeletal) have been shown to cause both cardiac and skeletal myopathies, thereby emphasising its importance for the normal functioning of the sarcomere. Mutations in cardiac MyBP-C are a major cause of hypertrophic cardiomyopathy (HCM), while mutations in skeletal MyBP-C have been implicated in a disease of skeletal muscle—distal arthrogryposis type 1 (DA-1). Here we report the first detailed electron microscopy studies on human cardiac and skeletal tissues carrying MyBP-C gene mutations, using samples obtained from HCM and DA-1 patients. We have used established image averaging methods to identify and study the axial distribution of MyBP-C on the thick filament by averaging profile plots of the A-band of the sarcomere from electron micrographs of human cardiac and skeletal myopathy specimens. Due to the difficulty of obtaining normal human tissue, we compared the distribution to the A-band structure in normal frog skeletal, rat cardiac muscle and in cardiac muscle of MyBP-C-deficient mice. Very similar overall profile averages were obtained from the C-zones in cardiac HCM samples and skeletal DA-1 samples with MyBP-C gene mutations, suggesting that mutations in MyBP-C do not alter its mean axial distribution along the thick filament

Outcomes of outpatient ureteral stenting without fluoroscopy at Groote Schuur Hospital, Cape Town, South Africa

Background. Ureteral stenting is generally a theatre-based procedure that requires a multidisciplinary team and on-table imaging. Limited hospital bed numbers and theatre time in our centre in Cape Town, South Africa, have led us to explore an alternative approach.Objectives. To see whether outpatient insertion of ureteric stents under local anaesthesia without fluoroscopy was a possible and acceptable alternative to theatre-based ureteral stenting.Methods. Ureteral stenting (double-J stents and ureteric catheters) was performed with flexible cystoscopy under local anaesthesia and chemoprophylaxis, but without fluoroscopic guidance, in an outpatient setting. Every patient had an abdominal radiograph and an ultrasound scan of the kidney after the procedure to confirm stent position.Results. Three hundred and sixteen procedures (276 double-J stents and 40 ureteric catheters) were performed in 161 men and 155 women. The overall success rate for the procedures was 85.4%, independent of gender (p=0.87), age (p=0.13), type of device inserted (p=0.81) or unilateral/bilateral nature of the procedure (p=1.0). Procedures with a successful outcome were performed in a significantly (p<0.0001) shorter median time (10 minutes (interquartile range (IQR) 5 - 15)) than failed procedures (20 minutes (IQR 10 - 30)). Patients with a pain score of >5 experienced a significantly (p=0.02) greater proportion of failure (27.3%) than patients with a pain score of ≤5 (12.5%). Difficulties were encountered in 23.7% of procedures, with a significantly higher proportion being registered in failed interventions compared with successful ones (82.6% v. 13.7%; p<0.0001).Conclusions. The procedure was easily mastered and technically simple, and represents savings in cost, time and human resources in our setting.