Quantifying and modelling the carbon sequestration capacity of seagrass meadows-a critical assessment

Seagrasses are among the planet's most effective natural ecosystems for sequestering (capturing and storing) carbon (C); but if degraded, they could leak stored C into the atmosphere and accelerate global warming. Quantifying and modelling the C sequestration capacity is therefore critical for successfully managing seagrass ecosystems to maintain their substantial abatement potential. At present, there is no mechanism to support carbon financing linked to seagrass. For seagrasses to be recognised by the IPCC and the voluntary C market, standard stock assessment methodologies and inventories of seagrass C stocks are required. Developing accurate C budgets for seagrass meadows is indeed complex; we discuss these complexities, and, in addition, we review techniques and methodologies that will aid development of C budgets. We also consider a simple process-based data assimilation model for predicting how seagrasses will respond to future change, accompanied by a practical list of research priorities.

Chronic intraocular pressure elevation impairs autoregulatory capacity in streptozotocin-induced diabetic rat retina

Purpose: To assess ocular blood flow responses to acute IOP stress following 4 weeks of chronic IOP elevation in streptozotocin (STZ)-induced diabetic and control rats. We hypothesise that chronic IOP elevation for 4 weeks will further impair blood flow regulation in STZ-induced diabetic rats eyes. Methods: Two weeks following citrate buffer or STZ-injections chronic IOP elevation was induced in Long Evans rats via fortnightly intracameral injections of microspheres (15 μm) suspended in 5% polyethylene glycol. IOP was monitored daily. Electroretinography (ERG, -6.79-2.07 log cd s m-2) was undertaken at Week 4 to compare photoreceptor (RmPIII), ON-bipolar cell (Vmax) and ganglion cell dominant ERG [scotopic threshold response (STR)] components. 4 weeks post-chronic IOP induction, ocular blood flow (laser Doppler flowmetry) was measured in response to acute IOP challenge (10-100 mmHg, in 5 mmHg steps, each 3 min). Results: Four weeks of chronic IOP (mean ± S.E.M., citrate: 24.0 ± 0.3 to 30.7 ± 1.3 and STZ-diabetes: 24.2 ± 0.2 to 31.1 ± 1.2 mmHg) was associated with reduced photoreceptor amplitude in both groups (-25.3 ± 2.2% and -17.2 ± 3.0%, respectively). STZ-diabetic eyes showed reduced photoreceptor sensitivity (citrate: 0.5 ± 1.8%, STZ-diabetic: -8.1 ± 2.4%). Paradoxically ON-bipolar cell sensitivity was increased, particularly in citrate control eyes (citrate: 166.8 ± 25.9%, STZ-diabetic: 64.8 ± 18.7%). The ganglion cell dominant STR was not significantly reduced in STZ-diabetic rats. Using acute IOP elevation to probe autoregulation, we show that STZ-diabetes impaired autoregulation compared with citrate control animals. The combination of STZ-diabetes and chronic IOP elevation further impaired autoregulation. Conclusions: STZ-diabetes and chronic IOP elevation appear to be additive risk factors for impairment of ocular blood flow autoregulation.

A case study on developing a teacher's capacity in mathematical modelling

Research has indicated that for teachers to facilitate mathematical modelling activities in the mathematics classroom, they need to be familiar with the process of mathematical modelling. As such, it is imperative that teachers experience the whole mathematical modelling process. This paper reports on a Multi-tiered Teaching Experiment designed to help a teacher develop his capacity in the domain of mathematical modelling. Drawing on part of a larger case-based study conducted using Design Research phases situated within the Multi-tiered Teaching Experiment framework, the purpose of this paper is to exemplify how the research design fostered growth in teacher capacity through the natural development of critical moments of learning by the teacher during interactions between the researchers and the teacher-modeller himself. The potential of the Multi-tiered Teaching Experiment as a useful non-prescriptive teacher development approach building upon the existing repertoire of individual teachers will be discussed.

The role of accounting in building financial capacity of Indigenous Australians.

 This study investigated the empowering and/or disempowering role that accounting can play in the building of financial capacity of Indigenous Australians.