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The metal chelator PBT2 (5,7-dichloro-2-[(dimethylamino)methyl]-8-hydroxyquinoline) acts as a terdentate ligand capable of forming binary and ternary Cu2+ complexes. It was clinically trialed as an Alzheimer’s disease (AD) therapeutic but failed to progress beyond phase II. The β-amyloid (Aβ) peptide associated with AD was recently concluded to form a unique Cu(Aβ) complex that is inaccessible to PBT2. Herein, it is shown that the species ascribed to this binary Cu(Aβ) complex in fact corresponds to ternary Cu(PBT2)NIm[Aβ] complexes formed by anchoring of Cu(PBT2) on imine nitrogen (NIm) donors of His side chains. The primary site of ternary complex formation is His6, having a conditional stepwise formation constant at pH 7.4 (K [M−1] ) of log K = 6.4 ± 0.1, and a second site is supplied by His13 or His14 (log K = 4.4 ± 0.1). The stability of Cu(PBT2)NIm[H13/14] is comparable with that of the simplest ternary complexes involving free imidazole (log K = 4.22 ± 0.09) and histamine (log K = 4.00 ± 0.05). The 100-fold larger formation constant for Cu(PBT2)NIm[H6] indicates that outer-sphere ligand–peptide interactions strongly stabilize its structure. Despite the relatively high stability of Cu(PBT2)NImH6, PBT2 is a promiscuous Cu2+-binding ligand capable of forming a ternary Cu(PBT2)NIm complex with any ligand containing NIm donor. These ligands include histamine, L-His, and ubiquitous His side chains of peptides and proteins in the extracellular milieu, whose combined effect should outweigh that of a single Cu(PBT2)NIm[H6] complex regardless of its stability. We therefore conclude that PBT2 is capable of accessing Cu(Aβ) complexes with high stability but not specificity. The results have implications for future AD therapeutic strategies and understanding the role of PBT2 in the bulk transport of transition metal ions. Given the repurposing of PBT2 as a drug for breaking antibiotic resistance, ternary Cu(PBT2)NIm and analogous Zn(PBT2)NIm complexes may be relevant to its antimicrobial properties.

The recent Southeast Asian haze crisis has generated intense public scrutiny over the rate, methods and types of landscape change in the tropics. Debate has centred on the environmental impacts of large-scale agricultural expansion, particularly the associated loss of high carbon stock forest and forests of high conservation value. Focusing on palm oil—a versatile food crop and source of bioenergy—this paper analyses national, international and corporate policy initiatives in order to clarify the current and future direction of oil palm expansion in Malaysia and Indonesia. The policies of ‘zero burn’, ‘no deforestation’ and ‘no planting on peatlands’ are given particular emphasis in the paper. The landscape implications of corporate commitments are analysed to determine the amount of land, land types and geographies that could be affected in the future. The paper concludes by identifying key questions related to the further study of sustainable land use policy and practice.

Peatlands provide a wide range of ecosystem services, the most important of which are terrestrial carbon storage, maintenance of biodiversity and protection of water resources. Exploitation of UK peatlands may be detrimental to these services, but scientific understanding and quantification of the effects is currently limited. This paper considers the possibility of imposing a levy on the exploitation of peatland, which would be used to fund high-quality prioritised research into the impacts of such human interventions, thereby enabling improvements to environmental management during the development process. The viability of the concept was explored with a group of peatland stakeholders. The group included most of the significant stakeholders with an interest in development on peatland, including regulators, developers and consultants. Qualitative and semi-quantitative responses were gathered by direct consultation with individuals and using a questionnaire to determine group responses. The latter were generally positive. Offered a choice of research funding mechanisms, stakeholders responded most positively to a levy. Whilst other funding mechanisms were also viewed positively a levy (in the form proposed or with some modification) was regarded as equitable by a large majority and workable by a smaller majority. Developers were reluctant to pledge full support to the proposal but recognised the importance of a number of the concerns that it was designed to address.

We report on the experience of Loughborough University’s Eureka Centre for Mathematical Confidence in establishing a small pilot project to provide one-to-one mathematics support for neurodiverse students who attend other local universities and where no such provision is available. We outline the background to the scheme and report on the three students involved.

In an attempt to determine the trophic history of the Myall Lakes complex (New South Wales, Australia) δ13Corg, δ15N and Corg:N profiles were determined for bulk organic matter of two short sediment cores from Bombah Broadwater and Myall Lake. 210Pb profiles and sediment types indicate significantly different trophic trajectories during the time periods examined. δ13Corg and Corg:N indicate Bombah Broadwater has been dominated by increasing inputs of terrestrial organic material over the last century, thought to be related to watershed disturbance including agricultural activity. Primary production appears to be dominated by phytoplankton. δ15N remained relatively stable at around 1‰ until the mid–1970s when there was a sharp increase to 4.7‰, interpreted as an influx of sewage-derived material. These observations offer an insight into the recent trophic changes at the site. Sedimentation rates are noticeably lower in Myall Lake and the most recent sediment is a flocculent organic rich deposit overlying mineral clay. δ13Corg and Corg:N values indicate a transition from plankton to macrophyte dominated primary production around 1800AD. δ15N values become increasingly negative from approximately 1900AD. This is interpreted as being due to increasing reliance by macrophytes on nitrogen recycled from decomposing sediments driven by natural infilling and eutrophication in this basin. The contrasting sedimentation rates, sediment types and geochemical profiles suggest the different basins of this water body are subject to substantially different internal and external influences which should be considered in management decisions.

SUMMARYThere is a need for coordinated research for the sustainable management of tropical peatland. Malaysia has 6% of global tropical peat by area and peatlands there are subject to land use change at an unprecedented rate. This paper describes a stakeholder engagement exercise that identified 95 priority research questions for peatland in Malaysia, organized into nine themes. Analysis revealed the need for fundamental scientific research, with strong representation across the themes of environmental change, ecosystem services, and conversion, disturbance and degradation. Considerable uncertainty remains about Malaysia's baseline conditions for peatland, including questions over total remaining area of peatland, water table depths, soil characteristics, hydrological function, biogeochemical processes and ecology. More applied and multidisciplinary studies involving researchers from the social sciences are required. The future sustainability of Malaysian peatland relies on coordinating research agendas via a ‘knowledge hub’ of researchers, strengthening the role of peatlands in land-use planning and development processes, stricter policy enforcement, and bridging the divide between national and provincial governance. Integration of the economic value of peatlands into existing planning regimes is also a stakeholder priority. Finally, current research needs to be better communicated for the benefit of the research community, for improved societal understanding and to inform policy processes.

One of the primary challenges of the Water Framework Directive (WFD) of the Euro- pean Union is to provide a guide for the recovery of surface waters from pollution. However, few studies deal with reference conditions according to the WFD in coastal waters. Using the urbanised Laajalahti Bay (Helsinki, Finland) as an example, reference conditions and pollution history were defined using the stratigraphy of diatoms, sediment geochemistry, stable isotopes, sedimentary pig- ments, long-term monitoring results of water quality, and nutrient-loading. Principal components analysis was used to generate a multidimensional index of water quality on the basis of the sediment data. We distinguished 5 phases: (1) a pre-industrial phase (before ca. 1815); (2) a phase of slight human disturbance (ca. 1815 to 1900); (3) an onset of anthropogenic impact (ca. 1900 to 1955); (4) a severe pollution phase (ca. 1955 to 1975); (5) basin recovery and a phase of internal loading (from ca. 1975 onwards). Phase 2 was used to define reference conditions. Phase 1 was not used as it occurred before the formation of the semi-enclosed bay by post-glacial isostatic land-uplift. There was good agreement between the sedimentary record and the water-quality data during Phase 4. Despite an improvement in water quality after the local municipal treatment plant closed in 1986, Laajalahti Bay is still far from reference conditions due to internal loading.

This study investigates changes in perceived consumption, beliefs and attitudes about beef and other proteins over three time periods that included much major media coverage of BSE-related issues. Demographic, consumption frequency of meat and other proteins and attitude scales relating to beef and BSE were administered to a sample of 1065 shoppers as they left a supermarket. Significant changes in most of the consumption measures were found over the three time periods. Many sex and age differences were also found. Attitudes correlated positively with both consumption of beef and pork and negatively with consumption of quorn. Explanations for the findings are offered in terms of the theories of reasoned action, cognitive dissonance and attribution and the health belief model. Implications for possible interactions between long-term changes in beef consumption and those due to the BSE crisis are considered in terms of the justification for continuing to eat beef.

This paper presents a study of changes in eutrophication over the past 100 years in a fertile estuary. The Danish estuary Mariager Fjord is a long, narrow sill-fjord with a permanently anoxic basin. In 1997 anoxia spread from the basin to the entire inner estuary, killing almost all eukaryotes and prompting debate on the causes. This paper reports a multi-proxy survey of 210Pb-dated sediment cores from the anoxic basin. Analyses of diatoms, dinoflagellates, pigments and geochemical proxies were used to determine changes in ecosystem structure over the past 100 years. The aim was to establish ‘base-line conditions’, for management purposes, of the biological structure prior to 1900, and to examine possible causes of changes observed. Geochemical proxies total nitrogen (TN), total carbon (TC) and biogenic silica (BSi) were consistently high throughout the sediment record. Increased concentrations of pigments and natural isotopes (δ13C, δ15N) suggested increasing production and nutrient loading. The main changes in the biological proxies occurred between 1915 and the 1940s, and indicated that the estuary has been somewhat eutrophic since 1900, but that the eutrophication process increased over the past 100 years. A reconstruction of TN concentration by a diatom-based transfer function supports this interpretation, with inferred TN ca. 1900 around 60 μmol l−1, and an increase in TN concentration over the past century to ca. 130 μmol l−1 by 1995. Inferred TN decreased to ca. 100 μmol l−1 by 2001, similar to present day monitoring data.

Spermatozoa of the plains mouse (Pseudomys australis), like those of most Australian old endemic rodents, contain, in addition to an apical hook, two further processes that extend from the upper concave surface of the head, the ventral processes. This study shows that these processes contain thiol-rich cytoskeletal proteins, which presumably help to maintain their rigidity during sperm transport, together with the overlying cell membrane having abundant intramembranous proteins. To determine the possible functional significance of these processes, an in vitro study of spermatozoon–zona binding was undertaken. The findings suggest that initial sperm binding occurs by way of the cell membrane over the acrosome of the apical hook and that, subsequently, the lateral surfaces of the ventral processes also become tightly bound to the zona matrix. These ventral processes may therefore have evolved to increase sperm adhesion to the outer zona surface and/or to enhance stabilisation of the spermatozoon at the time of zona binding and initial penetration of the egg coat.

Electron spin transient nutation (ESTN) experiments show that the spin multiplicity of the ground state of C603- in frozen solution is a doublet with S = 1/2. In purified samples, there is no evidence for excited states or other species with higher multiplicity. In the anions of C120On- (n = 2, 3, 4), where the CW EPR experiments have shown that a mixture of species is present, ESTN experiments confirm that a doublet with S = 1/2 is associated with the 3- anion and triplets with S = 1 are associated with the 2- and 4- anions. A weak nutation peak attributable to ms = -1/2 ↔ 1/2 transitions within a quartet state may arise from association of anions with spins of 1/2 and 1 in solute aggregates.