25 research outputs found
A manifold destiny : advancing the frontiers of the ADOR process
This thesis deals with the various attempts to expand the ADOR (Assembly, Disassembly,
Organisation and Reassembly) process. This includes the use of the ADOR process to
incorporate new elements into a zeolite framework, the expansion of the ADOR process
to other germanosilicate frameworks, and the first ever synthesis of a new ADORable
germanosilicate and its subsequent daughters.
Chapter 4 deals with the expansion of the ADOR process to the already known ADORable
zeolite UTL, using the organisation and reassembly steps to incorporate Al and P,
resulting in the formation of a zeolite-AlPO hybrid with distinct silicate layers connected
by AlPO based s4r linkages. The material was shown to contain Al and P species and was
unstable to acidic medium, atypical of the wholly silica zeolite frameworks produced by
the ADOR process. MAS NMR studies showed the presence of both tetrahedral P and Al
species in the material and that the presence of Si-OH groups was limited. Indicating that
the layers had been reconnected with Al and P now present, forming a zeolite-AlPO
hybrid. 29
Si-enriched materials were synthesised to confirm the presence of P-O-Si bonds,
through 2D MAS NMR correlation experiments; however, results were limited due to the
lack of signal strength.
Chapter 5 deals with attempts to expand the ADOR process by applying the ADOR process
to other already known germanosilicates. It was found that the non-ideal ADORable
candidates NUD-1 and ITQ-33 were unable to undergo a controlled disassembly process,
primarily due to their high Ge content and distribution of d4r/d3r. The zeolites ITQ-38
and IM-20 showed more promise. Both could undergo disassembly to form a layered
material, which could then be organised and reassembled to form new materials.
However, these materials were shown to not form perfect daughter zeolites and had a high
degree of disorder. This was associated with the complexity of the ADOR process and the
many factors that play a role in each step.
Chapter 6 deals with the use of a family of SDAs (with the same biphenyl backbone) to
synthesise new ADORable zeolites. The synthesis of the SDAs and their use in various
zeolite syntheses was discussed. The potential of these SDAs for the synthesis of new
zeolites was then evaluated. The investigations were relatively successful with the
successful formation of an ADORable zeolite, which was already known, UTL. However,
the suitability of such SDAs also put into question, due to their instability under
hydrothermal conditions.
Chapter 7 discussed the first successful a priori synthesis of a parent germanosilicate and
its daughter zeolites by the ADOR process. The successful synthesis of an ADORable
zeolite (SAZ-1) was conducted with the use of an imidazolium-naphthalene based SDA.
Investigations were first conducted into changing the synthesis condition, exploring the
impact of these changes on the resulting products, and optimising the synthesis
conditions to favour the formation of the new zeolite SAZ-1. These investigations led to
the new zeolite framework SAZ-1, which showed similarities to the zeolites NUD-2 and
CIT-13, which were developed simultaneously by other institutions. The properties of the
SAZ-1 framework were discussed and were found to be highly suitable for the ADOR
process. SAZ-1 was then successfully disassembled, organised, and reassembled to form
two new daughter zeolites SAZ-2 and SAZ-3. The alumination of SAZ-1P to form
aluminated SAZ-2 and SAZ-3 was also attempted. Both zeolites showed an increase in
catalytic activity, compared to the typical pure-silica daughter zeolites. The layers of SAZ-
1P were also able to undergo the same shifting process as seen for the âunfeasibleâ zeolites
IPC-9 and IPC-10, but the resultant products were not as ordered as these previous
examples. This in addition to the previous work highlighted some of the non-ideal
properties of SAZ-1 compared to other ADORable zeolites, like UTL
Multiple spatial behaviours govern social network positions in a wild ungulate
The structure of wild animal social systems depends on a complex combination of intrinsic and extrinsic drivers. Population structuring and spatial behaviour are key determinants of individualsâ observed social behaviour, but quantifying these spatial components alongside multiple other drivers remains difficult due to data scarcity and analytical complexity. We used a 43âyear dataset detailing a wild red deer population to investigate how individualsâ spatial behaviours drive social network positioning, while simultaneously assessing other potential contributing factors. Using Integrated Nested Laplace Approximation (INLA) multiâmatrix animal models, we demonstrate that social network positions are shaped by twoâdimensional landscape locations, pairwise space sharing, individual range size, and spatial and temporal variation in population density, alongside smaller but detectable impacts of a selection of individualâlevel phenotypic traits. These results indicate strong, multifaceted spatiotemporal structuring in this society, emphasising the importance of considering multiple spatial components when investigating the causes and consequences of sociality
Developing expert scientific consensus on the environmental and societal effects of marine artificial structures prior to decommissioning
This work was supported by the UK Natural Environment Research Council and the INSITE programme [INSITE SYNTHESIS project, grant number NE/W009889/1].Thousands of artificial (âhuman-madeâ) structures are present in the marine environment, many at or approaching end-of-life and requiring urgent decisions regarding their decommissioning. No consensus has been reached on which decommissioning option(s) result in optimal environmental and societal outcomes, in part, owing to a paucity of evidence from real-world decommissioning case studies. To address this significant challenge, we asked a worldwide panel of scientists to provide their expert opinion. They were asked to identify and characterise the ecosystem effects of artificial structures in the sea, their causes and consequences, and to identify which, if any, should be retained following decommissioning. Experts considered that most of the pressures driving ecological and societal effects from marine artificial structures (MAS) were of medium severity, occur frequently, and are dependent on spatial scale with local-scale effects of greater magnitude than regional effects. The duration of many effects following decommissioning were considered to be relatively short, in the order of days. Overall, environmental effects of structures were considered marginally undesirable, while societal effects marginally desirable. Experts therefore indicated that any decision to leave MAS in place at end-of-life to be more beneficial to society than the natural environment. However, some individual environmental effects were considered desirable and worthy of retention, especially in certain geographic locations, where structures can support improved trophic linkages, increases in tourism, habitat provision, and population size, and provide stability in population dynamics. The expert analysis consensus that the effects of MAS are both negative and positive for the environment and society, gives no strong support for policy change whether removal or retention is favoured until further empirical evidence is available to justify change to the status quo. The combination of desirable and undesirable effects associated with MAS present a significant challenge for policy- and decision-makers in their justification to implement decommissioning options. Decisions may need to be decided on a case-by-case basis accounting for the trade-off in costs and benefits at a local level.Publisher PDFPeer reviewe
Developing expert scientific consensus on the environmental and societal effects of marine artificial structures prior to decommissioning
Thousands of artificial (âhuman-madeâ) structures are present in the marine environment, many at or approaching end-of-life and requiring urgent decisions regarding their decommissioning. No consensus has been reached on which decommissioning option(s) result in optimal environmental and societal outcomes, in part, owing to a paucity of evidence from real-world decommissioning case studies. To address this significant challenge, we asked a worldwide panel of scientists to provide their expert opinion. They were asked to identify and characterise the ecosystem effects of artificial structures in the sea, their causes and consequences, and to identify which, if any, should be retained following decommissioning. Experts considered that most of the pressures driving ecological and societal effects from marine artificial structures (MAS) were of medium severity, occur frequently, and are dependent on spatial scale with local-scale effects of greater magnitude than regional effects. The duration of many effects following decommissioning were considered to be relatively short, in the order of days. Overall, environmental effects of structures were considered marginally undesirable, while societal effects marginally desirable. Experts therefore indicated that any decision to leave MAS in place at end-of-life to be more beneficial to society than the natural environment. However, some individual environmental effects were considered desirable and worthy of retention, especially in certain geographic locations, where structures can support improved trophic linkages, increases in tourism, habitat provision, and population size, and provide stability in population dynamics. The expert analysis consensus that the effects of MAS are both negative and positive for the environment and society, gives no strong support for policy change whether removal or retention is favoured until further empirical evidence is available to justify change to the status quo. The combination of desirable and undesirable effects associated with MAS present a significant challenge for policy- and decision-makers in their justification to implement decommissioning options. Decisions may need to be decided on a case-by-case basis accounting for the trade-off in costs and benefits at a local level
GA4GH: International policies and standards for data sharing across genomic research and healthcare.
The Global Alliance for Genomics and Health (GA4GH) aims to accelerate biomedical advances by enabling the responsible sharing of clinical and genomic data through both harmonized data aggregation and federated approaches. The decreasing cost of genomic sequencing (along with other genome-wide molecular assays) and increasing evidence of its clinical utility will soon drive the generation of sequence data from tens of millions of humans, with increasing levels of diversity. In this perspective, we present the GA4GH strategies for addressing the major challenges of this data revolution. We describe the GA4GH organization, which is fueled by the development efforts of eight Work Streams and informed by the needs of 24 Driver Projects and other key stakeholders. We present the GA4GH suite of secure, interoperable technical standards and policy frameworks and review the current status of standards, their relevance to key domains of research and clinical care, and future plans of GA4GH. Broad international participation in building, adopting, and deploying GA4GH standards and frameworks will catalyze an unprecedented effort in data sharing that will be critical to advancing genomic medicine and ensuring that all populations can access its benefits
Accelerated surgery versus standard care in hip fracture (HIP ATTACK): an international, randomised, controlled trial
Simvastatin Sodium Salt and Fluvastatin Interact with Human Gap Junction Gamma-3 Protein
Finding pleiomorphic targets for drugs allows new indications or warnings for treatment to be identified. As test of concept, we applied a new chemical genomics approach to uncover additional targets for the widely prescribed lipid-lowering pro-drug simvastatin. We used mRNA extracted from internal mammary artery from patients undergoing coronary artery surgery to prepare a viral cardiovascular protein library, using T7 bacteriophage. We then studied interactions of clones of the bacteriophage, each expressing a different cardiovascular polypeptide, with surface-bound simvastatin in 96-well plates. To maximise likelihood of identifying meaningful interactions between simvastatin and vascular peptides, we used a validated photo-immobilisation method to apply a series of different chemical linkers to bind simvastatin so as to present multiple orientations of its constituent components to potential targets. Three rounds of biopanning identified consistent interaction with the clone expressing part of the gene GJC3, which maps to Homo sapiens chromosome 7, and codes for gap junction gamma-3 protein, also known as connexin 30.2/31.3 (mouse connexin Cx29). Further analysis indicated the binding site to be for the N-terminal domain putatively âregulatingâ connexin hemichannel and gap junction pores. Using immunohistochemistry we found connexin 30.2/31.3 to be present in samples of artery similar to those used to prepare the bacteriophage library. Surface plasmon resonance revealed that a 25 amino acid synthetic peptide representing the discovered N-terminus did not interact with simvastatin lactone, but did bind to the hydrolysed HMG CoA inhibitor, simvastatin acid. This interaction was also seen for fluvastatin. The gap junction blockers carbenoxolone and flufenamic acid also interacted with the same peptide providing insight into potential site of binding. These findings raise key questions about the functional significance of GJC3 transcripts in the vasculature and other tissues, and this connexinâs role in therapeutic and adverse effects of statins in a range of disease states
Two-Step Dry Gel Method Produces MgAPO-11 with Low Aspect Ratio and Improved Catalytic Performance in the Conversion of Methanol to Hydrocarbons
In this article, the synthesis, characterization and catalytic performance of three MgAPO-11 catalysts with distinct crystal morphologies (sunflower, ball and candy) are presented. Among the three samples, the candy-like MgAPO-11-C, with high crystallinity and uniform particle size (of about 1 ”m), was synthesized for the first time by using a unique two-step dry gel method. Despite the similar acid strength of the three samples, the different and distinct morphologies of the catalysts resulted in very different methanol-to-hydrocarbons (MTH) performances. In particular, the candy-like MgAPO-11-C presented the best MTH performance with the highest total conversion capacity (4.4 gMeOH·gcatalystâ1 hâ1) and the best selectivity to C5+ aliphatics (64%)
Ageing red deer alter their spatial behaviour and become less social
Social relationships are important to many aspects of animals' lives, and an individual's connections may change over the course of their lifespan. Currently, it is unclear whether social connectedness declines within individuals as they age, and what the underlying mechanisms might be, so the role of age in structuring animal social systems remains unresolved, particularly in non-primates. Here we describe senescent declines in social connectedness using 46 years of data in a wild, individually monitored population of a long-lived mammal (European red deer, Cervus elaphus). Applying a series of spatial and social network analyses, we demonstrate that these declines occur because of within-individual changes in social behaviour, with correlated changes in spatial behaviour (smaller home ranges and movements to lower-density, lower-quality areas). These findings demonstrate that within-individual socio-spatial behavioural changes can lead older animals in fission-fusion societies to become less socially connected, shedding light on the ecological and evolutionary processes structuring wild animal populations
MAPO-18 Catalysts for the Methanol to Olefins Process: Influence of Catalyst Acidity in a High-Pressure Syngas (CO and H2) Environment
The transition from integrated petrochemical complexes toward decentralized chemical plants utilizing distributed feedstocks calls for simpler downstream unit operations. Less separation steps are attractive for future scenarios and provide an opportunity to design the next-generation catalysts, which function efficiently with effluent reactant mixtures. The methanol to olefins (MTO) reaction constitutes the second step in the conversion of CO2, CO, and H2 to light olefins. We present a series of isomorphically substituted zeotype catalysts with the AEI topology (MAPO-18s, M = Si, Mg, Co, or Zn) and demonstrate the superior performance of the M(II)-substituted MAPO-18s in the conversion of MTO when tested at 350 °C and 20 bar with reactive feed mixtures consisting of CH3OH/CO/CO2/H2. Co-feeding high pressure H2 with methanol improved the catalyst activity over time, but simultaneously led to the hydrogenation of olefins (olefin/paraffin ratio < 0.5). Co-feeding H2/CO/CO2/N2 mixtures with methanol revealed an important, hitherto undisclosed effect of CO in hindering the hydrogenation of olefins over the BrĂžnsted acid sites (BAS). This effect was confirmed by dedicated ethene hydrogenation studies in the absence and presence of CO co-feed. Assisted by spectroscopic investigations, we ascribe the favorable performance of M(II)APO-18 under co-feed conditions to the importance of the M(II) heteroatom in altering the polarity of the MâO bond, leading to stronger BAS. Comparing SAPO-18 and MgAPO-18 with BAS concentrations ranging between 0.2 and 0.4 mmol/gcat, the strength of the acidic site and not the density was found to be the main activity descriptor. MgAPO-18 yielded the highest activity and stability upon syngas co-feeding with methanol, demonstrating its potential to be a next-generation MTO catalyst