Initial geological considerations before installing ground source heat pump systems

The performance of an open- or closed-loop ground source heat pump system depends on local geological conditions. It is important that these are determined as accurately as possible when designing a system, to maximize efficiency and minimize installation costs. Factors that need to be considered are surface temperature, subsurface temperatures down to 100–200 m, thermal conductivities and diffusivities of the soil and rock layers, groundwater levels and flows, and aquifer properties. In addition, rock strength is a critical factor in determining the excavation or drilling method required at a site and the associated costs. The key to determining all of these factors is an accurate conceptual site-scale model of the ground conditions (soils, geology, thermogeology, engineering geology and hydrogeology). The British Geological Survey has used the modern digital geological mapping of the UK as a base onto which appropriate attributes can be assigned. As a result it is possible to generate regional maps of surface and subsurface temperatures, rock strength and depth to water. This information can be used by designers, planners and installers of ground source heat pump systems. The use of appropriate geological factors will assist in creating a system that meets the heating or cooling load of the building without unnecessary overengineering

A Solidification Phenomenon in Random Packings

We prove that uniformly random packings of copies of a certain simply-connected figure in the plane exhibit global connectedness at all sufficiently high densities, but not at low densities

Polarized synchrotron emission in quiescent black hole X-ray transients

We present near-infrared polarimetric observations of the black hole X-ray binaries Swift J1357.2-0933 and A0620-00. In both sources, recent studies have demonstrated the presence of variable infrared synchrotron emission in quiescence, most likely from weak compact jets. For Swift J1357.2-0933 we find that the synchrotron emission is polarized at a level of 8.0 +- 2.5 per cent (a 3.2 sigma detection of intrinsic polarization). The mean magnitude and rms variability of the flux (fractional rms of 19-24 per cent in K_s-band) agree with previous observations. These properties imply a continuously launched (stable on long timescales), highly variable (on short timescales) jet in the Swift J1357.2-0933 system in quiescence, which has a moderately tangled magnetic field close to the base of the jet. We find that for A0620-00, there are likely to be three components to the optical-infrared polarization; interstellar dust along the line of sight, scattering within the system, and an additional source that changes the polarization position angle in the reddest (H and K_s) wave-bands. We interpret this as a stronger contribution of synchrotron emission, and by subtracting the line-of-sight polarization, we measure an excess of ~ 1.25 +- 0.28 per cent polarization and a position angle of the magnetic field vector that is consistent with being parallel with the axis of the resolved radio jet. These results imply that weak jets in low luminosity accreting systems have magnetic fields which possess similarly tangled fields compared to the more luminous, hard state jets in X-ray binaries.Comment: Accepted to MNRA

Optimising self-managed funding for people with a long-term disability: dialogue summary

A day-long stakeholder dialogue was held on 5 March, 2015 to consider the factors which influence the uptake of self-managed funding by people with a long-term disability, and identify barriers and facilitators to the implementation and uptake of self-managed funding. Sixteen people participated. Discussions noted the following key considerations: The term ‘self-managed’ funding is more appropriate for people with long-term disability, particularly those who experience cognitive impairment. It should be assumed that all people with a long-term disability have the right to take up self-managed funding. Every person with a long-term disability has some capacity to self-manage their funding, and efforts should focus on building this capacity through education and training. Although people with a long-term disability may not want to take up self-managed funding the first time it is offered to them, every effort should be made to allow them ample time to consider it and opportunities provided to enable consumers and carers to ask for more information about what is required to participate. The approach to self-managed funding needs to be different for people with catastrophic injury compared with other conditions. Self-managed funding should be offered early for maximal uptake. To date, in the early implementation stages of current models, more people with spinal cord injury (SCI) than people with traumatic brain injury (TBI) have taken up self-managed funding; this is assumed to be a reflection of the additional complexities in the needs of people with TBI. To have greater success in the uptake of self-managed funding for people with a traumatic brain injury (TBI), there needs to be considerable thought about making the processes involved appropriate, particularly for those with cognitive and behavioural impairments. The capacity of people with a TBI to undertake the tasks associated with self-managed funding needs to be assessed by staff who have trained skills and also reasonable expectations of what can be accomplished. The relationship of the Carers and Family members with a person with a TBI needs to be supported through a range of offerings for self-managed funding. Funding agencies and service providers need to build trust and be willing to work collaboratively with people with long-term disabilities to ensure that they can consider self-managed funding as a means of empowerment and control. Encouraging and actively supporting people in peer support networks to talk to others about what the experience of self-managed funding is like and/or having consumer organisations conduct forums that present real-life experiences were considered next steps to increasing the uptake of self-managed funding

Further Attempts to Isolate and Identify the Selenium Protective Factor of Linseed Oil Meal

A number of different substances provide varying degrees of protection against selenium poisoning. Several workers have reported a protective effect shown by proteineous materials. Of these, one researcher found linseed oil meal to be superior to other materials tested. Further studies have led to the partial separation of selenium protective factor from linseed oil meal. The studies described here were undertaken as a continuation of the effort to separate and attempt to identify the selenium protective principle or principles known to be present in linseed oil meal. Several different approaches were used and are discussed

Examining the role of structural dynamics in the assembly and function of the multidrug efflux pump AcrAB-TolC

Membrane efflux pumps are a leading cause of increasing multidrug resistant bacterial infections, which pose a significant threat to global human health. Understanding the mechanisms that underpin their function is critical for the development of inhibitors targeting these systems, with the aim being to ‘revive’ the activities of pre-existing antibiotics known to suffer bacterial resistance. AcrAB-TolC is a membrane spanning, tripartite multidrug efflux pump native to Escherichia coli and prototypical of homologous systems across other ESKAPE bacteria. The work in this thesis investigates the role of structural dynamics in the function, assembly, and inhibition of AcrAB-TolC, with a focus on the membrane fusion protein (MFP) AcrA, to reveal critical information on how these efflux systems work, which could be essential for developing novel methods of inhibition to combat multidrug resistance. Throughout this work, structural mass spectrometry (MS) techniques such as hydrogen deuterium exchange mass spectrometry (HDX-MS) and native MS were used alongside a range of complementary biophysical/biochemical techniques to investigate AcrAB-TolC.This work reveals that AcrA lipidation promotes the propensity of AcrA to form oligomers, whereas a non-lipidated, water soluble AcrA construct (AcrAS) is still monomeric. Moreover, HDX-MS showed AcrAS exhibits increased backbone structural dynamics at pH 6.0 compared to pH 7.4, yet this was largely tempered by the presence of magnesium. In the periplasm, the pH can often be ∼1.7 pH units lower than in the cytosol, and there is a significantly higher concentration of magnesium ions (7.56 times). This suggests a regulatory role of magnesium to help AcrA function within the periplasmic environment. To expand the investigations on AcrAS further, a soluble pseudo-dimer construct (AcrASD) was used to infer biological information on the AcrA functional dimer. It was found the pseudo-dimer has unique structural dynamics compared to AcrA, with extensive protection in the α-helices and in regions of the αβ-barrel and MP domains. Furthermore, whilst AcrAS and AcrASD appeared to bind peptidoglycan similarly, AcrASD had a higher propensity to form higher order complexes with AcrB. This suggests dimerization may help prime the AcrA protomers for interactions with its binding partners.Traditionally, efflux pumps inhibitors (EPIs) have been targeted against AcrB, but none have made it past clinical trials, often due to toxicity issues. This has led to a switch in focus for the next generation of EPIs, with AcrA becoming a promising target. In this work, HDX-MS and native MS were used in combination with molecular dynamics (MD) simulations, to investigate the effect of a recently identified EPI, NSC 60339, on the structural dynamics of AcrAS. The data showed NSC 60339 likely binds to AcrA in a cleft bridging the lipoyl and αβ-barrel domains, stabilising these areas as well as the MP domain which usually exhibits intrinsic disorder; NSC 60339 inhibition of AcrASD presented the same. This work proposes the first mechanism of action regarding an AcrA inhibitor and reveals a promising new way to target the AcrAB-TolC complex.Due to the hydrophobic nature of membrane proteins, a suitable membrane mimetic is required for in vitro investigations. As the AcrAB-TolC multidrug efflux pump spans the entire Gram-negative cell envelope and are therefore membrane proteins, studying them in lipid environments rather than detergents is essential as they provide a more representative environment. In this work, HDX-MS was used to show MBX-3756 stabilises the hydrophobic trap of AcrB in membrane scaffold protein (MSP) nanodiscs. Furthermore, a novel SMALP-liposome-SMALP assay was utilised to show that previously designed AcrB antimicrobial peptides did not make the AcrB trimer, purified in styrene maleic acid lipid particles (SMALPs), dissociate into monomers. Lastly, assembly of the AcrAB-TolC complex was probed using two different pull-down assays and native polyacrylamide gel electrophoresis (PAGE), however the heterogeneity and hydrophobicity of SMALPs complicated these investigations, combined with the slow energetics of this assembly in vitro.<br/

Service-Disabled Veteran Small Business Owners\u27 Success Strategies

The federal government has been inconsistent in meeting the mandated contracting set-aside goals of 3% to aid service-disabled veteran small business owners. Guided by the general systems theory, the purpose of this qualitative exploratory case study was to explore what strategies an owner and 2 senior managers of a small service-disabled veteran-owned business in the Washington, DC metropolitan used to obtain federal contracts. The owner and senior members represented those responsible for strategic vision, development of business opportunities, and the company acquisition process. Data were collected from semistructured face-to-face interviews and corporate documents. Member checking and transcript review were completed to strengthen trustworthiness of interpretations of the participants\u27 responses. Based on the methodological triangulation of the data sources collected, 6 themes emerged from the data analysis as key strategies to obtain federal contracts: business practices, business development of opportunities to attain growth, marketing to obtain opportunities to bid, networking to gain industry knowledge on trends and markets, understanding federal government contracts which emphasized the federal acquisition system access and availability of procurement information, and contract bidding which emphasized the importance of solution development. The findings from the study may contribute to social change by providing insights and strategies for service-disabled veteran small business owners in sustaining profitability through obtaining government contracts. The data from this study may contribute to the prosperity of the veteran small business owners, their employees, their families, and local communities

Robotic Astronomy with the Faulkes Telescopes and Las Cumbres Observatory Global Telescope

We present results from ongoing science projects conducted by members of the Faulkes Telescope (FT) team and Las Cumbres Observatory Global Telescope (LCOGT). Many of these projects incorporate observations carried out and analysed by FT users, comprising amateur astronomers and schools. We also discuss plans for the further development of the LCOGT network.Comment: 8 pages, 2 figures, conference proceedings from "Workshop on Robotic Autonomous Observatories", held at Malaga, Spain from 18-21 May 2009, acccepted for publication in Advances in Astronom