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Human memory function is highly variable, fluctuating between periods of high and low performance even within a given person. Neurosurgical patients with indwelling electrodes present a unique opportunity to study the neural correlates of this variability and to define both the features of neural activity at a given brain location and the functional connections between brain regions that predict variability in memory encoding and retrieval. Here, I will describe our recent efforts to characterize brain networks that support memory via correlative (passive neural recording) and causal (direct electrical stimulation) approaches. Throughout the brain, we find that low-frequency networks exhibit reduced local power but stronger functional connectivity during successful episodic encoding and retrieval. Furthermore, many canonical memory regions emerge as hubs of such low-frequency connections, including the lateral frontotemporal cortices, the parahippocampal gyrus – and within it – the entorhinal cortex. High-frequency bands (i.e. gamma, 30+ Hz) almost exclusively exhibit desynchronization during successful memory operations. We recently extended these correlative studies and used intracranial stimulation to ask whether functional connections imply causality. We confirmed that electrical stimulation evokes increases in theta power at remote regions, as predicted by the strength of low-frequency functional connections. This relation was strongest when stimulation occurred in or near white matter. These findings demonstrate the importance of low-frequency connectivity to episodic memory, integrating these findings over spatial scales and through causal and correlative approaches.

Synthetic methods based on sol-gel chemistry are attractive solution-based routes to many simple and complex materials. The non-hydrolytic procedures are viable alternatives to classical aqueous techniques and these condensation reactions are inherently suitable for fabrication of mixed-metal and multimetallic oxidic and hybrid inorganic-organic systems. We developed novel non-hydrolytic sol-gel routes to several classes of porous xerogels, such as silicophosphates and -phosphonates, aluminophosphates, Al, Ti, Zr, and Sn silicates, hybrid aromatic organosilicates, and organosilicophosphates. The polycondensation reactions are based on elimination of small molecules, such as trimethylsilyl ester of acetic acid, dialkylacetamides, silylamines, ethers or alcohols. These elimination reactions provide microporous xerogels with high surface areas. Control of porosity and pore size is achieved by several methods, such as choice of suitable precursors, application of bridging groups, or addition of Pluronic templates. Residual organic groups on the surface allow for chemical modification and anchoring of various groups. Calcination in air provides xerogels that are stable at temperatures up to 500 C and show superior catalytic activity and selectivity in various catalytic reactions. The prepared xerogels were characterized by solid-state 13C, 27Al, 29Si, 31P NMR, IR, surface area analysis, DRUV-vis, TGA and XRD

There are three open questions in physics which seem unrelated:Why is there only matter around us? How neutrinos acquire their tiny masses? Why all particles in Nature have integer electric charges?It turns out that these open questions are related. In the talk I will explain these open questions, the connection between them, and describe the on-going theoretical andexperimental efforts in understanding them.

Low-dimensional nanostructures, which have at least one nano-scale length scale and at least one long length scale and include technologically promising cases like layered materials and nanowires, can exhibit unusual van der Waals dispersion forces. These manifest via "non-additive" contributions to the dispersion energy, which are excluded from models, such as D3, which sum over contributions across different constituent atoms. This talk will discuss the origin, role, and general weirdness of such effects. We will discuss the Dobson scheme for describing such effects and show some systems where conventional approaches to dispersion miss important qualitative and quantitative physics. New methods which capture some or all of these effects will be described. The importance of dispersion forces will be contextualised. Finally, we will digress into a new frontier of method development – easy modelling of low-lying excited states.

Radio frequency (RF) coil design for ultra-high field MRI scanners is an active field of research. We have recently developed an 8-channel transmit, 32-channel receive 7T head coil at the University of Glasgow. We focused on an open-faced design to make the setup less claustrophobic and more acceptable in a clinical environment. Furthermore, the coil can be used in both the scanner modes. I will also present our internal validation process which allows home-built RF coils to be used in vivo.