Exploring the invasion of rangelands by Acacia mearnsii (black wattle): biophysical characteristics and management implications

Australian acacias have spread to many parts of the world. In South Africa, species such as A. mearnsii and dealbata are invasive. Consequently, more effort has focused on their clearing. In a context of increasing clearing costs, it is crucial to develop innovative ways of managing invasions. Our aim was to understand the biophysical properties of A. mearnsii in grasslands as they relate to grass production and to explore management implications. Aboveground biomass (AGB) of A. mearnsii was determined using a published allometric equation in invaded grasslands of the northern Eastern Cape, South Africa. The relationships among the A. mearnsii leaf area index (LAI), normalised difference vegetation index (NDVI) and AGB were investigated. The influence of A. mearnsii LAI and terrain slope on grass cover was also investigated. Strong linear relationships between NDVI, LAI and AGB were developed. Acacia mearnsii canopy adversely impacted grass production more than terrain slope (p < 0.05) and when LAI approached 2.1, grass cover dropped to below 10% in infested areas. Reducing A. mearnsii canopy could promote grass production while encouraging carbon sequestration. Given the high AGB and clearing costs, it may be prudent to adopt the ‘novel ecosystems’ approach in managing infested landscapes.     

Eosinophilic cystitis in a female German wire-haired pointer

A 7-month-old, intact female, German wire-haired pointer presented with a 3-week history of stranguria, pollakiuria, and dysuria that was nonresponsive to antibiotics. Two prior episodes of dysuria-stranguria appeared to respond to antibiotic therapy. Bladder wall biopsies revealed eosinophilic cystitis and the dog responded well to medical management.     

Nutrition education and Mediterranean diet: exploring the teaching process of a school-based nutrition and media education project in Cretan primary schools

BACKGROUND: During the past few decades there has been a gradual abandoning of the traditional Mediterranean diet by the population of Crete and especially among the younger generations. Since this is related to the rapidly increasing morbidity and mortality rates from chronic diseases, the need for educating young people on the principles of good nutrition becomes increasingly important. It is also acknowledged that the epidemiological field needs to focus on studying the implementation process, since this will allow for a deeper understanding of the outcomes. OBJECTIVES: The aims of the present study were to explore the process of implementing an innovation in Cretan primary schools and to identify best teaching practices and principles. DESIGN: In three state primary schools on the island of Crete, 107 children took part in a 30-h nutrition and media education programme. Classroom observations were used to define attitudes towards the programme and teaching methods. Besides baseline and post evaluation, the pupils were also interviewed about 11 months after the end of the programme. IMPLEMENTATION: During observation of the teaching process, emerging issues were the teacher's motivation and interest in the course, his/her preparation before each class, teaching ability and communication skills, the respect and discipline he/she kept and the innovative teaching methods used. In some cases researcher intervention in the classroom could not be avoided. FINDINGS AND CONCLUSIONS: Overall, individual teacher willingness and teaching skills were mainly responsible for the quality of teaching, the variety of educational methods used in classrooms and pupils' interest in the course. Changes in pupils' knowledge and recall of the course were related to teacher enthusiasm but also to researcher intervention. Exploring the teaching and learning process allowed a deeper understanding of the data. It is concluded that attempts to introduce the principles of a Mediterranean diet to children through nutrition education require innovative, enthusiastic and highly motivated teachers.     

Electrochemical Method for the Rapid on Site Screening of Cadmium and Lead in Soil and Water Samples

Rapid field-based screening methods for the semi-quantitative determination of heavy metals are desirable to support the increasing demand for the rapid characterization of contaminated sites. Single-use sensors have been fabricated using low-cost screen-printing (thick film) technology. These electrodes, coupled with differential pulse anodic stripping voltammetry (DPASV), have provided a rapid, inexpensive on site screening device for the simultaneous field-based determination of cadmium (Cd) and lead (Pb) in soil and water samples in the microgram per litre/kilogram range. A simplified soil extraction procedure, using 1 mol l^?1 aqua regia and a 3 min ultrasonic sample agitation, has been developed to allow field-based device usage. Extraction efficiency was evaluated using a soil certified reference material (CRM). Recoveries of 64% and 52% for Cd and Pb respectively were obtained, with a relative standard deviation (RSD) of <8% for both analytes (n = 10). Soil samples (82) were tested using the combined extraction-DPASV procedure and compared against standard ICP-AES analysis. Correlation coefficients of 0.9782 and 0.9728 for Cd and Pb respectively demonstrate good correlation between methods. Analytical data is also reported for copper (Cu), but significant peak distortions reduce the confidence of the method for this metal. Results indicate that the combined extraction-DPASV method yields semi-quantitative data for rapid field-based site screening purposes.     

Glycaemic index, glycaemic load and risk of endometrial cancer: a prospective cohort study

OBJECTIVE: High-glycaemic-load diets may increase endometrial cancer risk by increasing circulating insulin levels and, as a consequence, circulating oestrogen levels. Given the paucity of epidemiological data regarding the relationship between dietary glycaemic index and glycaemic load and endometrial cancer risk, we sought to examine these associations using data from a prospective cohort study. DESIGN, SETTING AND SUBJECTS: We examined the association between dietary glycaemic load and endometrial cancer risk in a cohort of 49,613 Canadian women aged between 40 and 59 years at baseline who completed self-administered food-frequency questionnaires between 1982 and 1985. Linkages to national mortality and cancer databases yielded data on deaths and cancer incidence, with follow-up ending between 1998 and 2000. RESULTS: During a mean of 16.4 years of follow-up, we observed 426 incident cases of endometrial cancer. Hazard ratios for the highest versus the lowest quartile level of overall glycaemic index and glycaemic load were 1.47 (95% confidence interval (CI) = 0.90-2.41; P for trend = 0.14) and 1.36 (95% CI = 1.01-1.84; P for trend = 0.21), respectively. No association was observed between total carbohydrate or total sugar consumption and endometrial cancer risk. Among obese women (body mass index >30 kg m(-2)) the hazard ratio for the highest versus the lowest quartile level of glycaemic load was 1.88 (95% CI = 1.08-3.29; P for trend = 0.54) and there was a 55% increased risk for the highest versus the lowest quartile level of glycaemic load among premenopausal women. There was also evidence to support a positive association between glycaemic load and endometrial cancer risk among postmenopausal women who had used hormone replacement therapy. CONCLUSIONS: Our data suggest that diets with high glycaemic index or high glycaemic load may be associated with endometrial cancer risk overall, and particularly among obese women, premenopausal women and postmenopausal women who use hormone replacement therapy.