Comparison studies of unsaturated flow below annual and perennial plants.

Values of unsaturated water content determined with neutron moisture measurements (NMM) reveal different water profiles below different plantings. In the extremes, calibration requires a linear and logarithmic response (using the Lambert-W function) along with the normal submersion in a drum of water. Nevertheless a post-calibration with a hydraulic push sampler was used for confirmation. Data were collected at six pastures near the Western Australia coast near Geraldton, with four replicates through the profile. The sites have mostly sandy soils and receive 300-500 mm of rainfall annually. Findings generally showed that, if there was sufficient water, as in 2006, the perennials were able to use the water evenly throughout the vertical profile. Otherwise, with low rainfall, as in 2009, perennials struggle to survive and use less water than the annuals. Modelling of the soil water movement, plant growth and calibration/recalibration is and will be used to get a maximum likehood fit. Clearly, in desert conditions and little or no vegetation, rainfall tends to build up deep in the profile, increase salinity in groundwater, and create waterlogging. Any vegetation is helpful; perennials more so; provided they have sufficient water and are not significantly harvested.

Meeting report: consensus statement-Parkinson's disease and the environment: collaborative on health and the environment and Parkinson's Action Network (CHE PAN) conference 26-28 June 2007.

BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disorder. People with PD, their families, scientists, health care providers, and the general public are increasingly interested in identifying environmental contributors to PD risk. METHODS: In June 2007, a multidisciplinary group of experts gathered in Sunnyvale, California, USA, to assess what is known about the contribution of environmental factors to PD. RESULTS: We describe the conclusions around which they came to consensus with respect to environmental contributors to PD risk. We conclude with a brief summary of research needs. CONCLUSIONS: PD is a complex disorder, and multiple different pathogenic pathways and mechanisms can ultimately lead to PD. Within the individual there are many determinants of PD risk, and within populations, the causes of PD are heterogeneous. Although rare recognized genetic mutations are sufficient to cause PD, these account for < 10% of PD in the U.S. population, and incomplete penetrance suggests that environmental factors may be involved. Indeed, interplay among environmental factors and genetic makeup likely influences the risk of developing PD. There is a need for further understanding of how risk factors interact, and studying PD is likely to increase understanding of other neurodegenerative disorders.

An inquiry-based approach to teaching research design: asking the right questions.

To describe an inquiry-based learning activity and discuss the advantages of using such activities to demonstrate research design to undergraduate psychology students the authors presented students with the research problem of eyewitness memory recall and asked students to solve the problem, using the information provided by the course. Working in small groups, students reviewed eyewitness studies and designed their own research materials, including a videotaped theft and a CD-ROM version of the eyewitness survey and potential suspect line-up. Poststudy interviews showed that the students enjoyed the activity and felt that they had a better understanding of experimental research design than they had before the exercise. It is proposed that this activity may be a useful hands-on tool for instructors who have difficulty teaching students fundamental topics such as literature reviews, hypothesis testing, reliability and validity of research measures, and experimental design.