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The growing use of aptamers as target recognition elements in label-free biosensing necessitates corresponding transducers that can be used in relevant environments. While popular in many fields, capacitive sensors have seen relatively little, but growing use in conjunction with aptamers for sensing diverse targets. Few reports have shown physiologically relevant sensitivity in laboratory conditions and a cohesive picture on how target capture modifies the measured capacitance has been lacking. In this review, we assess the current state of the field in three areas: small molecule, protein, and cell sensing. We critically analyze the proposed hypotheses on how aptamer-target capture modifies the capacitance, as many mechanistic postulations appear to conflict between published works. As the field matures, we encourage future works to investigate individual aptamer-target interactions and to interrogate the physical mechanisms leading to measured changes in capacitance. To this point, we provide recommendations on best practices for developing aptasensors with a particular focus on considerations for biosensing in clinical settings.

Composites based on conductive nanowires embedded in elastomers are popular in a wide range of stretchable electronics applications where the requirements are either a stable or a highly increasing electrical resistance upon strain. Despite the widespread use of such composites, their production is not based in solid theoretical grounds but rather in empirical observations. The lack of such a framework is due to limitations in the methods for studying nanowire meshes, in particular the lack of knowledge on the spatial distribution of the nanowires and the change of their position under strain. This hurdle is overcome by collecting 3D reconstructed X-ray tomographies of silver nanowires embedded in polydimethylsiloxane (PDMS) under variable deformations and the missing structural information of the nanomaterial is obtained by unsupervised artificial intelligence image analysis. This allowed to reveal the precise assembly mechanisms of nanowire systems and derive a precise analytical formula for the piezoresistive response of the composite and finally to simulate the behavior of arbitrary samples in-silico., Funding Agencies|ETH ZurichETH Zurich; Swiss National Science FoundationSwiss National Science Foundation (SNSF) [165651]; Swiss Data Science Center; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO Mat LiU) [2009 00971]

Port Vila is the capital and largest city of the Melanesian island nation of Vanuatu, and is situated on the southern coast of Efate, the third largest island in Vanuatu. Metropolitan Port Vila is where more than a quarter of Vanuatu’s total population live. In 2016 the population of the city was approximately 75 000 and current growth rates are as high as 8% per annum. Population growth in Port Vila is much higher than in other provinces and the city is attracting internal migrants from all other islands in Vanuatu. Most new internal migrants reside in outer urban or peri-urban settlements where they do not generally have formal access to housing or land for growing food. Tropical Cyclone Pam (TC Pam) in March 2015 was one of the most severe cyclones in living memory, causing at least 16 fatalities and more than US$360 million worth of damage. Efate was one of the worst affected islands by TC Pam because of the infrastructure and population concentration in Port Vila. Vanuatu’s experience of TC Pam, followed immediately by a severe El Niño-Southern Oscillation drought which caused widespread food shortages, highlighted the vulnerability of Vanuatu to natural hazards and other risk factors. The Pacific Ecosystem-based Adaptation to Climate Change (PEBACC) Project responds to these vulnerability challenges. The five-year Project (implemented by the Secretariat of the Pacific Regional Environment Programme (SPREP)) explores and promotes Ecosystem-based Adaptation (EbA) options for adapting to climate change in the Pacific region. EbA is the practice of strengthening ecosystems to increase people’s ability to adapt to the impacts of climate change. It draws upon knowledge of ecosystem services and is based on the premise that if ecosystems are protected, remediated, or regenerated, this leads to healthier ecosystems, more ecosystem services, and therefore greater human well-being and resilience to the impacts of climate change. The current study continues

Rural electrification of Pacific Island Countries (PICs) through renewable energy is necessary for poverty alleviation, energy security, improved health, and to mitigate the effects of climate change, with solar PV being the preferred technological solution. However, electrification projects in PICs have had a high rate of failure, which has led to the adoption of various electrification strategies. This research has analysed the essential criteria for creating effective and enduring electrification models for rural household-scale electrification in PICs. A case study on self-initiated solar PV home systems (SHSs) demonstrated rural end-users‘ ability and desire to maintain SHSs of their own accord, while at the same time liberating their community of reliance on kerosene. The results suggested that market solutions that pay sufficient attention to social dimensions of project design and implementation are more likely to be successful in meeting end-users needs and providing enduring results. Such approaches have fewer organizational layers, allow for end-user participation and education, and encourage self-initiative. The need for such social solutions is well documented in the development literature, yet many of the electrification programs in PICs did not allocate sufficient funds to understanding and incorporating these social aspects. This research concludes that a proper balance in the overarching program design between the technical and social focus of projects is required, as each are equally important for project effectiveness and durability.

The traditional ecological knowledge (TEK) of local and indigenous people supports the resilience of social-ecological systems and is an important aspect of global biocultural diversity. However, TEK is at risk of erosion amid social and ecological change, and may be threatened by homogenising influences such as formal school systems. Loss of TEK is of particular concern in countries such as Vanuatu, a culturally diverse nation where TEK is a critical component of resource management, medicinal practice, and adaptive capacity. This thesis aims to fill four key literature gaps surrounding the variation, transmission, and maintenance of TEK, and is situated in four rural communities on Malekula Island, Vanuatu. This research employs an interdisciplinary mixed-methods approach across four core chapters. The first uses multi-model inferencing to show that systems of TEK are dynamic and complex, and that change is variable across domains of knowledge and segments of the population. Data in this chapter indicate that ethnomedical knowledge is at risk of erosion in younger age cohorts. The second core chapter shows that the cultural transmission of TEK is predominantly vertical in nature (i.e. passed from parent to child), is initiated during the early teens, and that some skills (such as the carving of ceremonial items) appear to be less salient to younger age cohorts. This chapter also notes a changing developmental niche for TEK transmission, and suggests that changes in both the setting and strategies for knowledge transmission are key mechanisms that drive TEK variation. The third and fourth core chapters discuss aspects of TEK maintenance: first, by examining top-down strategies for TEK revitalisation by eliciting local perceptions of the value of TEK to formal school systems; and second, by identifying the triggers and barriers to bottom-up, in situ TEK maintenance in local organisations known as 'kastom schools'. Both approaches have potential to conserve aspects o, Long fulap ples long world, kastom save blong envaeroment (KSBE) hemi stap lus. Ol jenis ia bambae i mekem i hard blong ol man blong lukaotem ol risos blong hem, mo bambae i mekem i hard blong ol jeneresen long fiuja blong stap strong taem envaeromen i jenis. Vanuatu hemi wan ples we i gat fulap difren kalja mo difren kaen envaeromen, mo kastom mo tredisen oli gat fulap importance long laef long ol man. I gat fulap rison we from wanem KSBE hemi important long Vanuatu: sam example olsem saed long lukaotem ol risos, saed long givim meresin long ol man, mo saed long givhan long ol man blong stap strong taem envaeromen i jenis. Be long Vanuatu, i gat wan problem, from we KSBE mo kastom i save lus, from we fulap niufala samting i kam insaed, ol envaeromen i jenis, mo ol youngfala oli no lanem gud ol save blong ol bubu blong olgeta. Risej ia i stap givhan blong saed long lanem save hao nao KSBE i stap lus, mo hao nao yumi save lukaotem hem mo mekem se i stap oltaem. Mi bin work long fofala komuniti long Malekula Island, mo mi bin traem save trifala samting. Namba wan samting, mi stap traem luk sipos KSBE hemi stap lus, mo wanem kaen samting i stap mekem se KSBE i lus. Mi bin yusum wan kaen interviu wetem 177 man mo woman long West Coast Malekula, mo mi askem evri wan blong telemaot fulap samting, olsem ol lif blong meresin. Ol risal oli telem se ol youngfala oli gat fulap KSBE, be olgeta oli no gat save olsem ol oldfala. Ol oldfala nomo oli gat save blong medel bus, be ol youngfala oli no stap lanem ol samting ia. Save ia i stap lus bigwan wetem ol man we oli go long market fulap mo we oli no laekem blong toktok lanwis tumas. Namba tu samting, mi stap traem luk hao nao ol man mo woman oli stap lanem ol save blong olgeta. Mi faendem se fulap long ol man mo woman oli lanem long mama mo papa blong olgeta, be mi luk save se ol fasin blong tijim ol difren kaen KSBE hemi stap jenis. Namba tri samting, mi stap luk long saed long hao nao yumi save lukaotem ol KSBE mo mekem se i s

The restoration of Nauru’s mined areas is fundamental to the future wellbeing of the people and ecosystems of Nauru. Extensive open cast phosphate mining on Nauru over the last 100 years has led to soil losses and landscape degradation to the extent that over 70% of this South-Western Pacific island state is now uninhabitable and almost all productive land has been lost. Significant landscape degradation has occurred and as a consequence the soils that remain are insufficient in volume and quality to achieve the Government’s restoration goals which support the long-term development of Nauru and the well-being of its people. The aim of this research is to evaluate aspects of cover-crop use as a means for soil restoration in Nauru. This research evaluates biomass production, phytoremediation potential, and germination success for a range of species in Nauruan soils. Field trials exploring biomass production and cadmium phytoextraction were performed, as was an experiment assessing the effects of cadmium on germination success. It was found that, in the circumstances assessed, biomass productivity was significantly determined by species, mulch use, soil type, and to a small degree – cadmium. Phytoextraction was significantly determined by tissue type. Germination success was not determined by soil cadmium, but soil type was a significant factor.

Adaptation to actual climate change and contingency planning to reduce vulnerability from likely climate change effects is crucial for the New Zealand dairy industry. Thus in alignment with international treaties and growing international pressure and speculation, the New Zealand Government in October 2007 announced an Emissions Trading Scheme (ETS) adaptable specifically to the New Zealand scene. This ETS passed into law in September 2008 through the enactment of the Climate Change Response (Emissions Trading) Amendment Act 2008. This thesis specifically looks at agriculture related emissions and calculates the liability faced by the dairy industry come 2013 when the industry is completely involved in the ETS. The purpose of this is to further aid the industry so that it can best align itself with the ETS in order to minimise this liability. This is not simply an aid to help the industry save money, as the minimisation of liability should come as a benefit to the environment through reduced emissions. There is also a second issue associated with this - as to whether the liability faced by the industry will be material enough in order for the farmers to actually mitigate their environmental impacts or will they simply bear the expense and ignore the opportunities to reduce their emissions against a baseline (and potentially generate carbon credits for sale) and/or offset any residual emissions through purchasing carbon credits? This therefore analysed the threshold of farmer's incomes whereby they will choose to abate their emissions rather than simply paying for their carbon emissions liability. This threshold obviously varied greatly through the dairying industry with differing factors - this was taken into account and discussed in detail. Other aspects influence this threshold also, factors such as the opportunity for the industry to market a niche product if they do achieve a low carbon or carbon neutral status for their products, cost competitiveness of availab

Concerns surrounding the environmental and social impacts of biofuel production have led to the rapid development of biofuel sustainability assessment schemes internationally. The New Zealand government is currently developing a voluntary biofuel sustainability reporting scheme. This thesis assesses the extent to which a sustainability standard could support the domestic biofuels industry, and avoid negative environmental and social impacts associated with biofuel production. It describes the current scope of the domestic biofuel industry, discusses relevant environmental and social concerns relating to biofuel production, and reviews international literature surrounding sustainable biofuel initiatives. From a study of the literature New Zealand biofuels appear more sustainable than most, although direct and indirect land-use change should be included for feedstocks from energy crops. Impacts vary across feedstocks and production methods, and each biofuel must be considered in its own merit. Qualitative semi-structured interviews were undertaken with key stakeholders from industry, relevant government agencies, non-governmental organisations, and biofuel experts to discuss the potential for a domestic biofuels sustainability standard. The majority of stakeholders interviewed supported the development of a government-led sustainability standard, which would include principles addressing greenhouse gas emissions, food security and biodiversity loss. There is good evidence to support the movement towards mandatory sustainability requirements, as soon as this is feasible. In the future, biofuels should be supported by technology-neutral policies (such as carbon-pricing) which reward their benefits, rather than indiscriminately promoting biofuels. The development of enforceable sustainability standards is crucial if biofuels are to contribute to a future low-carbon transport sector in New Zealand.

This research assesses the financial feasibility of a large scale copra-based biodiesel refinery in Vanuatu and whether any carbon finance could be sought to improve the viability of the project. The research cannot be perfectly predictive of the next fifteen years of financial situation, however, the research can quite accurately replicate the feasibility assessment that potential investors would make. The research finds that the project is not financially viable under current projections without carbon finance. The research also shows that carbon finance could be sought from a number of sources in order to make the project feasible. Under current projections the research finds that utilising the clean development mechanism would add approximately 2.9 million United States Dollars (USD) to the present value of the project. The conclusion from these results is that the proposed biodiesel project is sufficiently profitable to attract investors. The primary recommendation resulting from the research is that the stakeholders to the proposed biodiesel project begin an open discourse to work through any issues in order to develop a sustainable copra-based biodiesel refinery in Vanuatu to produce a substitute for the import of fossil diesel used for electricity generation in Port Vila. The secondary recommendation is that international climate change policy negotiators should keep in mind the full set of barriers when addressing the uptake of clean technology in developing countries; often it may not only be the financial feasibility that is preventing climate change mitigation activities.

Women's perceptions of their environment in two remote communities (Monxhill and Butmas, in Espiritu Santo, Vanuatu) were explored, as their perception is though to guide their involvement in environmental education. Qualitative insights from participatory fieldwork, using ranking exercise, community resource mapping and perception activities, showed that women of Monxhill see the forest as a place to live, to know and to learn about, to plan for and to take care of. In turn, women of Butmas see it as a resource, which has to be managed in order to provide the communities with food, materials and medicines; however, they also see it as a problem, which has to be solved. Furthermore, this research showed that these women are a key actors in community environmental education.

Vanuatu's common property natural resources provide essential ecological services for the global community and sustain the livelihoods of 80% of the Vanuatu population. Sustainable management of natural resources is dependent on locally developed systems that govern common property resources. Understanding the drivers of commons management problems from local resource-users' perspectives is essential to know how local governance systems can be supported and strengthened. I explore locally identified drivers of commons management problems using a case study of the Tangoa Island community of South Santo, Vanuatu. Methods include participatory rural appraisal (PRA) techniques and 31 interviews with local people. Literature from Vanuatu as well as 18 interviews with Vanuatu government departments, NGOs, and aid donors informs how relevant the issues identified in the case study are for other communities across Vanuatu. I found that drivers at different contextual scales, from local to global, affect two main elements of a community's cooperative capacity for commons management - social cohesion and governance systems. The issues identified by the Tangoa Island community affect many Vanuatu communities because they are driven by wider processes of social, cultural, economic, and institutional change. Approaches to support and strengthen local social and governance systems can target drivers at multiple contextual scales.