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Purpose: Algal research has been dominated by the use of marine biomass (mainly microalgae) as feedstock in the production of second-generation biofuels, albeit with limited economic success. A promising alternative strategy is the valorisation of seaweed (macroalgae), with the cascaded extraction of its high-value components, as well as lower-value components further downstream, under the 'biorefinery concept'. The goal of this study was to assess the environmental performance of one such marine biorefinery situated in the UK. Methods: Attributional life cycle assessment (LCA) was conducted on a hypothetical marine biorefinery coproducing fucoidan, laminarin, protein and alginate/cellulose packaging material (target product), from cultivated Saccharina latissima. The functional unit was the production of 1 kg of packaging material. A total of 6 scenarios were modelled, varying in coproduct management methodology (system expansion, mass allocation or economic allocation) and applied energy mix (standard or green energy). Sensitivity analysis was also conducted, evaluating the systems response to changes in allocation methodology; product market value; biomass composition and transport mode and distance. LCA calculations were performed using OpenLCA (version 1.10.3) software, with background processes modelled using the imported Ecoinvent 3.6 database. Environmental impacts were quantified under ReCiPe methodology at the midpoint level, from the 'Heirarchist' (H) perspective. Results and discussion: The overall global warming impacts ranged from 1.2 to 4.52 kg CO2 eq/kg biopolymer, with the application of economic allocation; 3.58 to 7.06 kg CO2eq/kg with mass allocation and 14.19 to 41.52 kg CO2eq/kg with system expansion — the lower limit representing the instance where green electricity is used and the upper where standard electricity is employed. While implementing the green energy mix resulted in a 67% reduction in global warming impacts, it also incurred a 2–9 fold increase in overall impacts in the categories of terrestrial acidification, human non-carcinogenic toxicity, land-use and terrestrial ecotoxicity. Economic allocation resulted in burden shifting most favourable to the packaging material pathway. Conclusions: This study demonstrates that the road to environmental optimisation in marine biorefineries is fraught with trade-offs. From the perspective of LCA — and by extension, the eco-design process that LCA is used to inform — when evaluating such product systems, it serves to strike a balance between performance across a broad spectrum of environmental impact categories, along with having consideration for the nature of energy systems incorporated and LCA methodological elements. [ABSTRACT FROM AUTHOR]

A 100 ps laser is used to probe the pressure generation, depth of the non-solid ablator, and the non-linear optical effects through tamper materials. Samples consisted of an aluminum ablator with tampers of sapphire and coverslip glass. In general, the sapphire tamped sample achieves higher pressures at lower laser intensities as compared to the coverslip glass tamped sample. Attempts to model the details of this set of experimental data with standard available radiation coupled hydrodynamic codes make clear that more physics is needed in these simulations to accurately predict the impact of the tamper material on the pressure generation and the depth of non-solid aluminum. [ABSTRACT FROM AUTHOR]

Purpose: Derelict fishing gear (DFG) is one of the most abundant and harmful types of marine litter that gets increasingly retrieved from the ocean. However, for this novel waste stream recycling and recovery pathways are not yet commonly established. To identify the most suitable waste management system, this study assesses the potential environmental impacts of DFG waste treatment options in Europe. Methods: This study applies an attributional life cycle assessment (LCA) to four DFG waste treatment scenarios, namely a mechanical recycling, syngas production, energy recovery and landfill disposal. The scope spans from the retrieval and transport processes to pre- and end-treatment steps until the outputs are sent to landfill or assumed to substitute products or energy. Primary data was collected from retrieval and waste treatment trials in Europe. Contribution, sensitivity and uncertainty analyses were conducted using the LCA software SimaPro and ReCiPe as the impact methodology. Results and discussion: The results show that the mechanical recycling and energy recovery achieve the lowest potential environmental impacts. The syngas production and landfill disposal scenario are not environmentally competitive because they require too much electricity, or their avoided production credits were too small to offset their emissions. Unlike the pre-treatment and transport processes, the retrieval and end-treatment processes have a significant impact on the overall results. The transport distances, energy mix and market and technological assumptions are least sensitive, while changes to the waste composition significantly affect the results. Especially a reduced lead content benefits the human toxicity impact potential of the landfill disposal scenario. The uncertainty analysis showed that the results are very robust in nine of twelve impact categories. Conclusions: This is the first LCA study that compares waste treatment options for marine litter. The results indicate that a disposal of DFG is hazardous and should be replaced with mechanical recycling or energy recovery. While this may be technologically possible and environmentally beneficial, economic and social factors should also be considered before a final decision is made. To further reduce environmental impacts, marine litter prevention should play a more important role. [ABSTRACT FROM AUTHOR]

The article reports on the evolution of the Investigative Learning program at Balmain Public School, a Stage 1 (Years K-2) inquiry and play-based program that fosters 21st-century learning capabilities. The program incorporates a flexible environment, authentic materials and open-ended tasks to develop critical, creative, computational and ethical thinking skills, providing students with a continuum of inquiry skills throughout their journey from Kindergarten to Year 2.

The past decades have seen an increasing interest in developing pathways to produce bio-based chemicals from lignocellulosic biomass and organic waste as renewable resources. Using biomass as a source of chemical building blocks is critical to a future sustainable chemical industry. The successful development of bio-chemicals will also have a profound impact in terms of the innovations of new polymers and materials, new solvents, and new bio-active compounds. This article provides a broad review of conventional thermal heating, microwave processing, and biochemical processing for the production of value-added bio-based chemicals. The potentially important but currently little exploited microwave-assisted processes are given particular attention and the microwave-specific, non-thermal effects are explored. The comparative merits of different approaches are evaluated from the techno-economic and environmental perspectives. The opportunities of integrated biorefineries are articulated, with the aim to actualize carbon-efficient valorization of lignocellulosic biomass and organic waste for synthesizing an array of products. [ABSTRACT FROM AUTHOR]

The chemical industry is increasingly looking to develop bio-based alternatives to petroleum-based platform chemicals, in order to reduce dependence on diminishing fossil resources and to decrease GHG emissions. 5-Hydroxymethylfurfural (HMF) and 2,5-furandicarboxylic acid (FDCA) are two examples of bio-based chemicals which could allow for the synthesis of a wide range of chemicals and materials, particularly polymers, from renewable feedstocks. This review paper summarises and critically evaluates results from existing life cycle assessment (LCA) and technoeconomic analysis (TEA) studies of HMF and FDCA synthesis and, by doing this, provides several points of advice for future investigations and assessments of synthetic routes towards these bio-based products. Chemical considerations such as choice of solvent system, catalyst and energy production are reviewed; and methodological issues in LCA, such as treatment of biogenic carbon and allocation methods, are discussed. Overall, results suggest that the production of HMF and FDCA-based products may offer lower impacts from CO2 emissions than their fossil-based counterparts, but this often comes with an increase in environmental impacts in other impact categories. Higher operating costs from expensive fructose feedstocks and high energy demands also make HMF and FDCA less economically viable than current chemicals. Moving forwards, further investigation into different lignocellulosic feedstocks, energy production units and the development of new catalytic systems may help in making HMF and FDCA production more favourable than the production of fossil-based counterparts. [ABSTRACT FROM AUTHOR]

Background: Heterotrophic single-cell oils (SCOs) are one potential replacement to lipid-derived biofuels sourced from first-generation crops such as palm oil. However, despite a large experimental research effort in this area, there are only a handful of techno-economic modelling publications. As such, there is little understanding of whether SCOs are, or could ever be, a potential competitive replacement. To help address this question, we designed a detailed model that coupled a hypothetical heterotroph (using the very best possible biological lipid production) with the largest and most efficient chemical plant design possible. Results: Our base case gave a lipid selling price of $1.81/kg for ~ 8,000 tonnes/year production, that could be reduced to $1.20/kg on increasing production to ~ 48,000 tonnes of lipid a year. A range of scenarios to further reduce this cost were then assessed, including using a thermotolerant strain (reducing the cost from $1.20 to $1.15/kg), zero-cost electricity ($ 1.12/kg), using non-sterile conditions ($1.19/kg), wet extraction of lipids ($1.16/kg), continuous production of extracellular lipid ($0.99/kg) and selling the whole yeast cell, including recovering value for the protein and carbohydrate ($0.81/kg). If co-products were produced alongside the lipid then the price could be effectively reduced to $0, depending on the amount of carbon funnelled away from lipid production, as long as the co-product could be sold in excess of $1/kg. Conclusions: The model presented here represents an ideal case that which while not achievable in reality, importantly would not be able to be improved on, irrespective of the scientific advances in this area. From the scenarios explored, it is possible to produce lower cost SCOs, but research must start to be applied in three key areas, firstly designing products where the whole cell is used. Secondly, further work on the product systems that produce lipids extracellularly in a continuous processing methodology or finally that create an effective biorefinery designed to produce a low molecular weight, bulk chemical, alongside the lipid. All other research areas will only ever give incremental gains rather than leading towards an economically competitive, sustainable, microbial oil. [ABSTRACT FROM AUTHOR]

BACKGROUND Macroalgae are gaining increasing interest as an important biomass feedstock. Yet when valorising marine biomass, the presence of salt can pose a substantial obstacle to the effectiveness of downstream biological and chemical processes, as well as the engineering infrastructure required. Accordingly, dewatering, washing and drying are often considered the first and crucial primary steps in processing marine biomass such macroalgae. The high costs of these processes can make further marine biorefinery commercialisation prohibitive. This investigation assesses simple pre‐treatments for macroalgal biomass in saltwater, thereby reducing the freshwater footprint, and removing the need for an energy‐intensive washing and drying stage. RESULTS: Using acid and basic catalysts, the carbohydrate and soluble protein components were fractionated into a soluble aqueous phase, for further fermentation and a solid phase suitable for hydrothermal liquefaction. The presence of saltwater was found to aid the fractionation process, solubilising more of the biomass. The use of H2SO4 produced more monosaccharides, whereas NaOH solubilised higher levels of biomass at lower temperatures. The aqueous phase was demonstrated to be suitable for biological processing with the salt tolerant yeast Metschnikowia pulcherrima, and the residual solids suitable for processing via hydrothermal liquefaction. CONCLUSION: By contrast with existing pre‐treatment strategies, we demonstrate that an entirely salt‐based biochemical conversion route is a potentially viable option. For the first time this work demonstrates that, rather than a hindrance, the presence of saltwater can be advantageous, and could provide an alternative, more cost‐effective pathway to achieving a successful macroalgal‐based biorefinery. [ABSTRACT FROM AUTHOR]

The article offers information related to the increase in literacy rate through investigative learning. It mentions about theories of child development, with play-based learning as a central component in evidence-based program; and need of child-centred, flexible learning environment for student’s individual strengths, background and readiness. It also mentions about importance of authentic context equal engagement, and engagement equals learning for teachers.

Background: Microbial oils – often termed single cell oils (SCOs) – offer an alternative to terrestrial oil crops across the energy, food and chemical industries. In addition to oils, a range of secondary metabolites can be produced from the heterotrophic organisms as part of a biorefinery system. Techno‐economic analysis (TEA) is an important tool for evaluating economic viability, and although TEA is subject to high uncertainties where production is still at the laboratory scale, the tool can play a significant role in directing further research to evaluate suitability of scale‐up. Results: SCO production from the oleaginous yeast Metschnikowia pulcherrima using sucrose, wheat straw and distillery waste feedstocks was evaluated at two production scales. At a scale of 100 t year−1 oil production a minimum estimated selling price (MESP) of €14 000 t–1 was determined for sucrose. This reduced to €4–8000 t–1 on scaling to 10 000 t year−1, with sucrose and wheat straw yielding the lowest MESP. Conclusions: Feedstock price and lipid yield had the greatest impact on overall economic return, though the valorization of co‐products also had a large effect, and further play between feedstock and system productivity strategies could bring the price down to be competitive with terrestrial oils in the future. The novel approach demonstrated here for the first time integrates uncertainty into economic analysis whilst facilitating decision‐support at an early technology development stage. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

An interview with Ariana Davis, Assistant Principal and Sophie Parsons, teacher at Balmain Public School is presented. It mentions that student engagement is inextricably linked to student learning, and that engagement is most powerful when linked to student interests; and also mentions that open classrooms and flexible learning spaces also bring their own challenges.

Abstract: BACKGROUND: 2‐phenylethanol (2PE) is a fragrance molecule predominantly used in perfumes and the food industry. It can be made from petrochemicals inexpensively, however, this is unsuitable for most food applications. Currently, the main method of production for the bio‐derived compound is to extract the trace amounts found in rose petals, which is extremely costly. Potentially fermentation could provide an inexpensive, naturally sourced, alternative. RESULTS: In this investigation, 2PE was produced from the yeast Metschnikowia pulcherrima, optimised in flasks before scaling to 2 L batch and continuous operation. 2PE can be produced in high titres under de novo process conditions with up to 1500 mg L−1 achieved in a 2 L stirred bioreactor. This is the highest reported de novo titre to date, and achieved through high sugar loadings coupled with low nitrogen conditions. The process successfully ran in continuous mode also, with a concentration of 650 mg L−1 of 2PE being maintained. The 2PE production was further increased by the ex novo conversion of phenylalanine and semi‐continuous solid phase extraction from the supernatant. Under optimal conditions 14 000 mg L−1 of 2PE was produced. CONCLUSIONS: The work presented here offers a novel route to naturally sourced 2PE through a scalable fermentation with a robust yeast highly suited to industrial biotechnology. © 2018 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]