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Based on discussions at the international workshop on “Thermoactive geotechnical systems for near-surface geothermal energy”, hosted at École Polytechnique Fédérale de Lausanne (EPFL), Switzerland ( http://www.olgun.cee.vt.edu/workshop/ ), this article attempts to provide a broad overview of the analysis methods used for evaluation of systems that use either boreholes or geo-structures for heat exchange. It identifies commonalities where knowledge transfer from the former to the latter can be made, and highlights where there are significant differences that may limit this cross-fertilisation. The article then focusses on recent developments and current understanding pertaining to the analysis of the thermo-mechanical interaction between a geostructure and the ground, and how this may be incorporated into the geotechnical design of energy geostructures. [ABSTRACT FROM AUTHOR]

The use of shallow geothermal energy systems that employ heat-exchange loops within trenches and boreholes is well established. The use of civil engineering structures that are in contact with the ground (geo-structures) to replace the more conventional heat-exchange methods is creating great interest in many countries. Bearing piles have been used for this purpose since the mid-1980s, retaining walls since the late-1990s and the use of tunnels has been explored since the early-2000s. With regards to transportation infrastructure shallow geothermal may be used to provide renewable heating and cooling to the infrastructure itself or adjacent users, or even to enhance safety by providing e.g. heat to de-ice bridges, station platforms, airport run-ways and the like. This paper presents an overview of the potential application energy geo-structures in transportation infrastructure through case studies and numerical simulations, and then goes on to discuss some of the issues associated with the potential use of geo-structures for heat exchange, in terms of construction, thermal operation and the impact of heating and cooling on the geo-structure. [ABSTRACT FROM AUTHOR]

Climate change will increase the magnitude and frequency of high temperatures, resulting in higher cooling demands in buildings and a possible diminished efficacy of the passive solutions that could be used to limit that increased demand. However, building energy simulations are often performed with past weather data files, ignoring the effect of the changing climate. Portuguese building certification regulations use standard TMY (typical meteorological year) weather files that were updated with RCP4.5 predictions. These updated weather files were used to reassess the impact of climate change on a hybridized ground–source heat pump (GSHP) system with piles, natural ventilation (NV) and personal comfort systems (PCS). Cooling loads increased the most in Porto and the least in Faro, varying from 3 to 163 %, with the exception of the GSHP–NV–PCS hybrid scenario in Lisbon, where the cooling load decreased 27 %. This increased unbalance of the thermal loads resulted in a higher build–up of heat in the ground, decreasing the fraction of load that could be covered by the GSHP, especially in Porto. Despite the increase in final energy needs for heating and cooling, the GSHP–NV–PCS approach is a resilient solution to supply heating and cooling in a warming climate, as it can still reduce final energy consumption by more than 90 %, relative to a non–hybrid approach. [ABSTRACT FROM AUTHOR]

A ground–source heat pump system (GSHP) can be an alternative to air–source heat pumps (ASHP), as exchanging heat with the ground instead of with the air can result in higher coefficients of performance (COP). However, unbalanced loads can significantly shift the temperature profile in the ground, decreasing the GSHP's overall performance. Hybrid systems can reduce the imbalanced loads and improve performance. This study proposed the use of personal comfort systems (PCS) and natural ventilation (NV) to decrease the thermal load imbalance in a cooling–dominated building. Building energy simulations were used to assess the performance of eight renewable heating and cooling solutions in three Portuguese cities (Porto, Lisbon and Faro): (1) ASHP, (2) GSHP, (3) ASHP–PCS, (4) GSHP–PCS, (5) ASHP–NV, (6) GSHP–NV, (7) ASHP–PCS–NV, (8) GSHP–PCS–NV. The simulation results show that without hybridization, the use of the GSHP resulted in an increase in ground temperature of more than 20 °C, over 50 years, which decreased its COP and rendered it unable to supply the full cooling load, and may not be acceptable in environmental terms. The use of either PCS or NV for hybrid cooling decreased the thermal cooling load and increased the energy efficiency of the GSHP system relative to the equivalent ASHP–hybrid. However, full coverage of the cooling load was still not always possible, as ground heat build–up was still high. Hybridization with both NV and PCS allowed full coverage of the thermal load by the GSHP. Both the cooling load and final energy needs decreased by over 90 %, and the increase in ground temperature was limited to about 6 °C. [ABSTRACT FROM AUTHOR]

We analyze the split exact sequences of (co)homology groups associated to the spaces of Dwyer which give rise to the centralizer decomposition and subgroup decomposition of the classifying space BG of a finite group. In the first instance these sequences have infinite length. We show that they give rise to finite sequences which are also split and exact. The sequences arise as the first page of a spectral sequence. [Copyright &y& Elsevier]

Abstract: A series of 5-N,N-disubstituted-5-aminopyrazole-3-carboxylic acids were prepared and found to act as highly potent and selective agonists of the G-Protein Coupled Receptor (GPCR) GPR109b, a low affinity receptor for niacin and some aromatic d-amino acids. Little activity was observed at the highly homologous higher affinity niacin receptor, GPR109a. [Copyright &y& Elsevier]

Abstract: A series of 3-nitro-4-substituted-aminobenzoic acids were prepared and found to act as potent and highly selective agonists of the orphan human GPCR GPR109b, a low affinity receptor for niacin. No activity was observed at the closely homologous high affinity niacin receptor, GPR109a. A second series, comprising 6-amino-substituted nicotinic acids was, also prepared and several analogues showed comparable activity to the nitroaryl series. [Copyright &y& Elsevier]

Abstract: A series of 5-alkyl pyrazole-3-carboxylic acids were prepared and found to act as potent and selective agonists of the human GPCR, GPR109a, the high affinity nicotinic acid receptor. No activity was observed at the highly homologous low affinity niacin receptor, GPR109b. A further series of 4-fluoro-5-alkyl pyrazole-3-carboxylic acids were shown to display similar potency. One example from the series was shown to have improved properties in vivo compared to niacin. [Copyright &y& Elsevier]

• Heat exchange between piles and surrounding ground. • Contextualizes reported response thermally-activated piles in cohesive media. • Demonstrates influence of pile mobilisation under mechanical load on thermal response as function of: factor-of-safety on shaft resistance, pile spacing within groups. • Characterises impact of heat loss from building on: Thermo-mechanical response of pile foundation, Heat exchange between piles and surrounding ground The thermal-activation of pile foundations for use within shallow geothermal energy systems has received much attention with a number of studies having reported full- and small-scale testing and/or numerical analysis. Various conditions in terms of pile type, ground profiles and thermal loading, have been considered in these studies, leading to a broad understanding of the thermo-mechanical behaviour of thermally-activated pile foundations. One area that requires further attention is the clarification of the foundation response under seasonal cyclic thermal loading. This study systematically assesses the impact of cyclic thermal loading in relation to the initial mechanical loading, for isolated floating piles and pile groups in a cohesive soil medium. For piles where the shaft resistance dominates the pile total resistance, it was found that irrecoverable movement will be small and thermal stress and pile head movements change in a cyclic and regular manner. It is shown that the effect of the coefficient of thermal expansion of the soil, is much reduced from that suggested in studies using constant thermal loads applied over long periods. The effect of the overlying building was explored and it is shown that thermal-activation of the pile foundation mitigates the effect of the imposition of a higher average temperature at the surface. [ABSTRACT FROM AUTHOR]

A novel antifungal strategy targeting the inhibition of calcineurin is described. To develop a calcineurin based inhibitor of pathogenic fungi, analogs of FK506 were synthesized that were able to permeate mammalian but not fungal cells. Antagonists in combination with FK506 were not immunosuppressive and retained antifungal activity in A. fumigatus . To reduce the dosage burden of the antagonist, murine oral PK was improved an order of magnitude relative to previous FK506 antagonists. [ABSTRACT FROM AUTHOR]

Abstract: 3-3 interpenetrating composites (IPCs) are novel materials with potentially superior multifunctional properties compared with traditional metal matrix composites. The aim of the present work was to evaluate the high strain rate performance of the metal–ceramic IPCs produced using a pressureless infiltration technique through dynamic property testing, viz. the split Hopkinson''s pressure bar (SHPB) technique and depth of penetration (DoP) analysis, and subsequent damage assessment. Though the IPCs contained rigid ceramic struts, the samples plastically deformed with only localised fracture in the ceramic phase following SHPB. Metal was observed to bridge the cracks formed during high strain rate testing, this latter behaviour must have contributed to the structural integrity and performance of the IPCs. Whilst the IPCs were not suitable for resisting high velocity, armour piercing rounds on their own, when bonded to a 3mm thick, dense Al2O3 front face, they caused significant deflection and the depth of penetration was reduced. [Copyright &y& Elsevier]

Abstract: Tricyclic pyrazole tetrazoles which are potent partial agonists of the high affinity niacin receptor, GPR109a, have been discovered and optimized. One of these compounds has proven to be effective at lowering free fatty acids in vitro and in vivo. [Copyright &y& Elsevier]

Abstract: A strategy for lead identification of new agonists of GPR109a, starting from known compounds shown to activate the receptor, is described. Early compound triage led to the formulation of a binding hypothesis and eventually to our focus on a series of pyrazole acid derivatives. Further elaboration of these compounds provided a series of 5,5-fused pyrazoles to be used as lead compounds for further optimization. [Copyright &y& Elsevier]

Abstract: Benzocanthinone ( 1 ) and five analogs ( 10 , 12–15 ) were prepared by radical-induced cyclizations of halo N-aroyl derivatives of β-carboline and carbazole. [Copyright &y& Elsevier]

Fosmanogepix (APX001) is a first-in-class prodrug molecule that is currently in Phase 2 clinical trials for invasive fungal infections. The active moiety manogepix (APX001A) inhibits the novel fungal protein Gwt1. Gwt1 catalyzes an early step in the GPI anchor biosynthesis pathway. Here we describe the synthesis and evaluation of 292 new and 24 previously described analogs that were synthesized using a series of advanced intermediates to allow for rapid analoging. Several compounds demonstrated significantly (8- to 32-fold) improved antifungal activity against both Cryptococcus neoformans and C. gattii as compared to manogepix. Further in vitro characterization identified three analogs with a similar preliminary safety and in vitro profile to manogepix and superior activity against Cryptococcus spp. [ABSTRACT FROM AUTHOR]