Climate change reduces extent of temperate drylands and intensifies drought in deep soils

Drylands cover 40% of the global terrestrial surface and provide important ecosystem services. While drylands as a whole are expected to increase in extent and aridity in coming decades, temperature and precipitation forecasts vary by latitude and geographic region suggesting different trajectories for tropical, subtropical, and temperate drylands. Uncertainty in the future of tropical and subtropical drylands is well constrained, whereas soil moisture and ecological droughts, which drive vegetation productivity and composition, remain poorly understood in temperate drylands. Here we show that, over the twenty first century, temperate drylands may contract by a third, primarily converting to subtropical drylands, and that deep soil layers could be increasingly dry during the growing season. These changes imply major shifts in vegetation and ecosystem service delivery. Our results illustrate the importance of appropriate drought measures and, as a global study that focuses on temperate drylands, highlight a distinct fate for these highly populated areas

YOUR SCIENCE IS IN THE MAIL

The Bachelor of Science (Extended) is a four-year program that provides a transition into tertiary science and technology study and is only available to Aboriginal and Torres Strait Islander students. A year of study in addition to the three-year BSc program comprises subjects in interdisciplinary science, mathematics and communication and provides students with foundation knowledge and skills for the wider BSc. ‘Delivering’ our practical program under COVID-19 Practical classes are key to a science degree. They develop critical skills and give student opportunities to apply their learning. ‘Prac’ is often the component that draws students to science and keeps them engaged. However, in the frantic transition from face-to-face to online delivery many science subjects were forced to deliver their practical experience via videos. As COVID-19 restrictions increased and our BSc (Ext) students returned to their home states, we saw an opportunity to maintain the hands-on nature of our practical classes using the services of Australia Post. This is a report on the design and evaluation of kits of postable laboratory equipment for interdisciplinary science. Our students used this kit of equipment to complete their practical program that included an environmental survey (chemistry and biology), simple mechanics (physics and biology), and investigations of living things (biology and geography). We will discuss our teaching approach which informed the design of the posted lab program, student feedback, the learning outcomes for students and consider the scalable elements of these ‘home experiments’ for large subjects

An investigation into the use of a movement assessment protocol for under 14 rugby league players in a talent development environment

This study investigated the use of a movement assessment protocol for under-14 rugby league players by evaluating the relationships between chronological age, maturation, and anthropometry, and fitness and qualitative movement assessments (QMA) of 84 rugby league players within a talent development environment. A one-way ANOVA showed Quartile 1 players were more mature, taller (173.0±7.4 vs 165.0±8.0 cm) and heavier (72.5 vs 58.7 kg) than Quartile 4 players, with no difference evident for fitness or QMA measures. Earlier maturing players had significantly greater upper body power (5.39±0.46 vs 4.42±0.68 m), 20m speed (3.48±0.14 vs 3.65±0.19s) and power pass QMA (13.88±2.18 vs 12.00±1.98) than later maturing players. Body mass was positively related to power pass fitness (r=0.50) and QMA (r=0.22) scores, with negative relationships found for vertical jump performance (r=-0.24), sprint QMA (r=-.29) and turn off either foot QMA (r=-0.26). There is a need to educate coaches about the use of both fitness testing and qualitative movement assessments to identify talented U14 rugby league players, which potentially reduces relative age and maturational biases

Hydrogen evolution and transport in semiconductors

Silicon-on-insulator structures are used for the fabrication of integrated electronic circuits, photonic devices and structures, and micro-electro-mechanical systems. The most common fabrication method for SOI is a hydrogen-induced cleavage technique in which ion-implanted hydrogen is employed to initiate and propagate cracks in a plane parallel to the silicon surface. Considerable research effort has been devoted to understanding this cleavage technique in (100) silicon but several fundamental issues remain unclear, including the role of stress on hydrogen platelet alignment. In addition, there is keen interest in extending the technique to other silicon orientations (i.e. (110) and (111)) and semiconductor materials (e.g. Ge). The intrinsic behaviour of hydrogen ion-implanted into Ge and Si was examined by ion beam analysis, optical profilometry and microscopy, to establish the influence of lattice damage and hydrogen evolution. In particular, hydrogen-induced blistering and crater formation under thermal annealing from T=300-650 degrees Celsius was studied to determine the activation energies in Ge and Si in several crystalline orientations. Similar techniques were employed as the influence of extrinsic applied stresses upon hydrogen's evolution within Si was studied, by mechanical stress application onto Si(100). XTEM was used to study the defect evolution related to the hydrogen and ion-implantation damage under anneals applied to samples under stress, in addition to samples produced in different stress conditions. Blistering rate and areal density was seen to follow logistic sigmoidal functions in all materials. Constant activation energies were measured for all Si samples under selected implantation conditions, but multiple activation energies were found in each Ge sample when the conditions were varied. Si(100) & Si(111) both blistered readily for all temperatures, Si(110) required higher H fluence and Ge showed inconsistent behaviour at different implantation conditions. Blister crater depth and roughness may be closer linked to local H concentration rather than total implantation fluence. High level doping of Si does not significantly change the dynamics of H blister formation, with potentially exploitable benefits for SOI production. Stress induced by ion implantation in Si and Ge is tensile, relaxes somewhat with thermal annealing, in the order of <1 MPa. Both 50 and 375um Si wafers behave similarly when implanted with H. Tensile stress applied to H-implanted thick Si(100) influenced hydrogen defect alignment within the lattice, shifting complexes to [110] and [100] planes following annealing. In ULTRATHIN Si, application of tensile stress may relatively diminish and compressive stress enhance diffusion of H, although any applied stress during implantation is seen to decrease H concentration. Applied stresses above 400 MPa cause the height of hydrogen surface blisters to decrease and density to increase. Blisters formed during annealing are not permanently decorated with nor contain hydrogen, whether under applied stress or not. Orientations of detectable defects are not strongly affected by application of stress, however concentrations are seen to decrease at high stress. The location of the ion-cut inducing defect does not appear to correspond to long term measurements of H or implantation damage, and may be even shallower, but this cannot be unambiguously confirmed

Impact of prolonged sitting on vascular function in young girls

Excessive sedentary behaviour has serious clinical and public health implications; however, the physiological changes that accompany prolonged sitting in the child are not completely understood. Herein, we examined the acute effect a prolonged period of sitting has upon superficial femoral artery function in 7- to 10-year-old girls and the impact of interrupting prolonged sitting with exercise breaks. Superficial femoral artery endothelium-dependent flow-mediated dilatation, total shear rate, anterograde and retrograde shear rates and oscillatory shear index were assessed before and after two experimental conditions: a 3 h uninterrupted period of sitting (SIT) and a 3 h period of sitting interrupted each hour with 10 min of moderate-intensity exercise (EX). A mixed-model analysis of variance was used to compare between-condition and within-condition main effects, controlling for the within-subject nature of the experiment by including random effects for participant. Superficial femoral artery endothelium-dependent flow-mediated dilatation decreased significantly from pre- to post-SIT (mean difference 2.2% flow-mediated dilatation; 95% confidence interval = 0.60–2.94%, P < 0.001). This relative decline of 33% was abolished in the EX intervention. Shear rates were not significantly different within conditions. Our data demonstrate the effectiveness of short but regular exercise breaks in offsetting the detrimental effects of uninterrupted sitting in young girls

The Development of Teaching Skills to Support Active Learning in University Science (ALIUS)

This paper describes an Australian Learning and Teaching Council funded project for which Learning Design is encompassed in the broadest sense. ALIUS (Active Learning In University Science) takes the design of learning back to the learning experiences created for students. ALIUS is not about designing a particular activity, or subject, or course, but rather the development of a method, or process, by which we have re-designed the way in which learning occurs in large university classrooms world wide

An interdisciplinary approach to foundation study in the Bachelor of Science (Extended)

BACKGROUND The Bachelor of Science (Extended) is a four-year degree that provides an additional pathway into Bachelor of Science study for Aboriginal and Torres Strait Islander students who do not meet the standard degree entry requirements. The BSc(Ext) contributes to increasing Indigenous student participation in tertiary science study, fields in which they are significantly underrepresented. CURRICULUM APPROACH The degree’s extension component comprises eight subjects taken during the first three semesters, in interdisciplinary science, mathematics, communication and Indigenous studies. The extension subjects embed students’ academic skills development, and science and mathematics knowledge and skills, to provide a foundation for success and further study in students’ chosen STEM specialisation. RESULTS Integrating science disciplines, Indigenous Knowledges and mathematics into the science subjects has provided an enriched curriculum that is valued by students, who comment on the importance of foundation knowledge and skills and the multiple ways of learning provided. We will use examples of this approach to highlight its potential, with particular emphasis on Indigenous Knowledges and student impact. DISCUSSION An interdisciplinary thematic approach is a key component of the curriculum design, examining science through lenses of chemistry, physics, biology and Indigenous Knowledges, to prepare students for a range of STEM futures

ALIUS: Active Learning in University Science - Leading Change in Australian Science Teaching

The ALIUS project is about leading change in the teaching of chemistry in large university classes. ALIUS is a collaboration of six Australian universities funded by an ALTC Leadership for Excellence in Learning and Teaching Grant (LE8-818). The aims of this project lie in three domains: • Development of project members as Science Learning Leaders • Development of the skills of project members in practice-based learning and teaching innovation • Creation of a virtual Learning Hub Methods being used to achieve these aims are: • Leadership- professional development in leadership specifically targeted at fostering change in academic teaching practice • Learning and Teaching Innovation - the U.S. NSF funded POGIL project will be used as a model for teaching innovation. Experienced POGIL instructors and facilitators brought from the U.S. run workshops and consultancies with ALIUS project members to build member skills in teaching innovation. • The learning hub (http://www.alius.edu.au/) will serve as a resource to share experiences in building teaching innovation, developed materials, resources about innovative teaching methods This presentation will report results and experiences of the project, including: • Experiences in implementing new teaching practices • Experiences in motivating changes in teaching practice of colleagues • Answers to uniquely Australian problems in implementation of POGIL style activities • Report on impact nationwide • Plans for next projec