344 research outputs found
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Solvent similarity index.
The Solvent Similarity Index (SSI) is a quantitative parameter we introduce for the comparison of the solvation properties of any solvent or solvent mixture. The Surface Site Interaction Model for Liquids at Equilibrium (SSIMPLE) was used to calculate the free energy of solvation of a single Surface Site Interaction Point (SSIP) on a solute. The SSIP representation of molecular surfaces was used to calculate the free energy of solvation for all possible solute polarities, generating a unique solvation profile for any solvent or solvent mixture. Quantitative comparison of the solvation profiles of two solvents was used as the basis for calculating the solvation similarity index. Values of SSI were calculated for all pairwise comparisons of 261 pure solvents at 298 K, and the results were used to classify solvents into groups according to their solvation properties. Applications to understanding the solvation properties of binary solvent mixtures and for identification of alternative solvents are illustrated.Engineering and Physical Sciences Research Council (EP/M506485/1
Synthesis and coordination chemistry of multidentate phosphine ligands
The work presented herein is concerned with the design, synthesis and characterisation of novel phosphorus containing ligands and the metal complexes thereof. Chapter 1 will provide an introduction to the field and present an overview of recent developments in the literature.
Chapter 2 deals with the development of a synthetic route towards triphosphine macrocycles. The synthesis of bis(2-(phosphino)ethyl)phosphines is presented and their coordination chemistry with first row transition metals (Cr, Fe, Ni, Cu) is described. The ability of these complexes to act as templates in the formation of macrocyclic ligands is assessed.
Chapter 3 explores the synthesis of novel chiral multidentate phosphine ligands derived from glycidyl phosphine synthons. The reaction of diphenylglycidyl phosphine with P, N and S based nucleophiles results in the rapid construction of chiral heterodonor ligand frameworks. Preliminary studies of the reactivity of these ligands with metal centres will be presented.
Chapter 4 investigates the synthesis of chiral-at-aluminium complexes based upon a novel γ-amino-β-hydroxyphosphine oxide ligand. Two discreet aluminium alkyl complexes were identified and the interconversion of these species was studied by spectroscopic and computational means.
Chapter 5 concerns the coordination chemistry of bicyclic multidentate ER-NHCs with Pd(0), Pt(0) and Au(I) metal centres. The M(0) complexes display an unexpected proclivity towards the κ1-C coordination mode. This further informs the discussion of the factors controlling the variable coordination chemistry of such ligands in the design of novel catalytic systems
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The SSIP approach to solvation
Intermolecular interactions, including hydrogen bonding, are important for governing many processes, including solvation, protein ligand binding and crystallisation.
Previously in the Hunter group, the Surface Site Interaction Point (SSIP) model of intermolecular interactions has been used to describe molecules as a set of discrete hydrogen bonding sites.
In this thesis I describe the prediction of phase properties using this molecular description, after giving an introduction to the wider area of phase property prediction.
Experimental equilibrium constants for formation of hydrogen bonded complexes was collated to allow for the reparameterisation of the relationship used to convert calculated electrostatic potentials into the hydrogen bond parameters used to describe the interaction properties of SSIPs, and a curated database of this information was created.
An overhaul of the software infrastructure, to allow greater exploitation of automation in the workflow, was undertaken.
Canonicalisation of data formats for information produced during the calculation has also been undertaken to provide a foundation for work in the following chapters.
Calculation of partition coefficients for a series of molecular datasets have been used to benchmark the performance of the surface site interaction model for liquids at equilibrium (SSIMPLE) which uses the SSIP description for molecules to calculate free energies.
Functional Group Interaction Profiles (FGIP) describe the energy change of two solute SSIPs interacting as a function of solute SSIP values.
These profiles provide insight into the strength of interactions within different solvents.
A selection of profiles for a range of solvents are included as examples.
The profiles provide a useful guide for how to tune interactions when designing systems which rely on intermolecular interactions for association.
Consideration of the solvation free energy of a single SSIP in a solvent as a function of SSIP value, has led to the development of a metric for solvent similarity.
The comparison of solvation free energy curves for different solvents and solvent mixtures led to the construction of similarity dendrograms that can be used for solvent selection in experimental systems.
Expansion of the approach to be used to examine the temperature dependence of the interactions, allowed the exploration of vapour liquid equilibria.EPSRC doctoral training studentship (grant code EP/M506485/1
Synthesis and coordination chemistry of multidentate phosphine ligands
The work presented herein is concerned with the design, synthesis and characterisation of novel phosphorus containing ligands and the metal complexes thereof. Chapter 1 will provide an introduction to the field and present an overview of recent developments in the literature.
Chapter 2 deals with the development of a synthetic route towards triphosphine macrocycles. The synthesis of bis(2-(phosphino)ethyl)phosphines is presented and their coordination chemistry with first row transition metals (Cr, Fe, Ni, Cu) is described. The ability of these complexes to act as templates in the formation of macrocyclic ligands is assessed.
Chapter 3 explores the synthesis of novel chiral multidentate phosphine ligands derived from glycidyl phosphine synthons. The reaction of diphenylglycidyl phosphine with P, N and S based nucleophiles results in the rapid construction of chiral heterodonor ligand frameworks. Preliminary studies of the reactivity of these ligands with metal centres will be presented.
Chapter 4 investigates the synthesis of chiral-at-aluminium complexes based upon a novel γ-amino-β-hydroxyphosphine oxide ligand. Two discreet aluminium alkyl complexes were identified and the interconversion of these species was studied by spectroscopic and computational means.
Chapter 5 concerns the coordination chemistry of bicyclic multidentate ER-NHCs with Pd(0), Pt(0) and Au(I) metal centres. The M(0) complexes display an unexpected proclivity towards the κ1-C coordination mode. This further informs the discussion of the factors controlling the variable coordination chemistry of such ligands in the design of novel catalytic systems
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SSIPTools: Software and Methodology for Surface Site Interaction Point (SSIP) Approach and Applications.
We present the SSIPTools suite of programs. SSIPTools is a collection of software modules enabling the use of the Surface Site Interaction Point (SSIP) molecular descriptors, used for the modeling of noncovalent interactions in neutral organic molecules. It contains an implementation of the workflow for the generation of the SSIP descriptors, as well as the Functional Group Interaction Profiles (FGIPs) and Solvent Similarity Indexes (SSIs) applications, based on the SSIMPLE (Surface Site Interaction model for the Properties of Liquids at Equilibria) approach.Engineering and Physical Sciences Research Council (EP/M506485/1
Trends and needs in the Australian child welfare workforce : An exploratory study
[Extract] Until recently, there has been limited focus on the nature and readiness of the broader child welfare workforce for stronger engagement in child abuse intervention and prevention, particularly the universal workforce. There is a concentration of effort and funding in the tertiary sector but there are now increasing calls to prioritise public health prevention.
An effective system of family supports, and early interventions entails an integration of programs and services across the three tiers of a public health system: primary, secondary and tertiary.
To support workers in ensuring the safety and wellbeing of children and young people, all organisations that offer services to vulnerable children, young people and families—directly or indirectly—need to be able to attract, recruit and sustain a reliable and appropriately qualified and skilled workforce.
This report presents findings from an exploratory study that examined broad-ranging, publicly available data to investigate emerging trends, issues and needs in the child welfare workforce and the educational profile of the workforce
Structural properties of the HNF-1A transactivation domain
Hepatocyte nuclear factor 1α (HNF-1A) is a transcription factor with important gene regulatory roles in pancreatic β-cells. HNF1A gene variants are associated with a monogenic form of diabetes (HNF1A-MODY) or an increased risk for type 2 diabetes. While several pancreatic target genes of HNF-1A have been described, a lack of knowledge regarding the structure-function relationships in HNF-1A prohibits a detailed understanding of HNF-1A-mediated gene transcription, which is important for precision medicine and improved patient care. Therefore, we aimed to characterize the understudied transactivation domain (TAD) of HNF-1A in vitro. We present a bioinformatic approach to dissect the TAD sequence, analyzing protein structure, sequence composition, sequence conservation, and the existence of protein interaction motifs. Moreover, we developed the first protocol for the recombinant expression and purification of the HNF-1A TAD. Small-angle X-ray scattering and synchrotron radiation circular dichroism suggested a disordered conformation for the TAD. Furthermore, we present functional data on HNF-1A undergoing liquid-liquid phase separation, which is in line with in silico predictions and may be of biological relevance for gene transcriptional processes in pancreatic β-cells.</p
Reconectando las colecciones de Cinchona (Rubiaceae) de la Real Expedición Botánica al Virreinato del Perú (1777-1816)
During the “Real Expedición Botánica al Virreinato del Perú”, 1777-1816, Hipólito Ruiz López (1754-1816), José Antonio Pavón Jiménez (1754-1840), Juan José Tafalla Navascués (1755-1811) and Juan Agustín Manzanilla (fl. 1793-1816) collected economically important specimens of anti-malarial cinchona bark (Cinchona spp.). In the 230 years since, these specimens have been dispersed across institutions in Spain, Britain, Germany and Italy. Two major sub-collections of these are found at the Real Jardín Botánico, Madrid, Spain (n = 243), and the Royal Botanic Gardens, Kew, UK (n = 188). The Kew collection arrived in Britain through Pavón and other Spanish botanists selling part of the collections. This study traces the history, trajectory and relationship of the collections between the two institutes.Durante la Real Expedición Botánica al Virreinato del Perú, 1777-1816, Hipólito Ruiz López (1754-1816), José Antonio Pavón Jiménez (1754-1840), Juan José Tafalla Navascués (1755-1811) y Juan Agustín Manzanilla (fl. 1793-1816) recolectaron especímenes de cortezas de quina (Cinchona spp.), importante económicamente como antimalárico. En los 230 años transcurridos desde entonces, estos especímenes se han dispersado por instituciones de España, Gran Bretaña, Alemania e Italia. Dos subcolecciones importantes se encuentran en el Real Jardín Botánico, Madrid, España (n = 243), receptor de la colección, y en Royal Botanic Gardens, Kew, Reino Unido (n = 188). La colección de Kew llegó a Gran Bretaña a través de Pavón y otros botánicos españoles que vendieron parte de las colecciones de la Expedición. Este estudio rastrea la historia, trayectoria y relación de estas colecciones compartidas entre estos dos centros de investigación
Perceptual phenomenology
I am looking at an apple. The apple has a lot of properties and some, but
not all, of these are part of my phenomenology at this moment: I am aware of these properties. And some, but not all, of these properties that I am aware of are part of my perceptual (or sensory) phenomenology. If I am attending to the apple’s color, this property will be part of my perceptual phenomenology. The property of being a granny smith apple from Chile is unlikely to be part of my perceptual phenomenology.
Here are two problems for anyone who is interested in conscious experience
in general, and perceptual experience in particular:
(a) How can we tell which properties are part of our phenomenology and
which ones are not?
(b) How can we tell which properties are part of our perceptual phenomenology and which ones are part of our non-perceptual phenomenology?
I will focus on (b) in this paper. My aim is twofold: I propose a methodology for answering the question of which properties are part of our perceptual phenomenology and I provide an example for how this methodology could be applied
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