Analysis of vertical ground loop heat exchangers applied to buildings in the UK

The work presented here deals with the design and performance of ground-source heat pumps and ground-sink cooling systems using vertical borehole arrays for commercial applications in the UK. Heating and cooling energy demands for a range of building and HVAC plant options are obtained by thermal modelling applied to four HVAC plant options: space heating only; heating with chilled ceilings; fan coil units and constant volume all-air plant. Ground loop designs are conducted for each system option using an impulse-response method and the parameters extracted from this are used in 10-year simulations of plant response which have been carried out using HVACSIM+. The 10-year time horizon was used to assess any degradation in earth temperature over time. The results show that a substantial reduction in energy (and, hence, carbon) can be expected of up to and exceeding 50% when using ground source heat pumps for winter heating with direct cooling in summer in association with moderate temperature cooling systems such as chilled ceilings. A degradation of earth temperature was evident with systems utilising limited cooling or no cooling but this did not appear to influence heat pump performance greatly. Practical Applications: Design and performance data for use in vertical ground loop (borehole) heat exchanger arrays providing source heat for heat pumps as well as direct cooling for buildings are generated and reported in this paper. The data should be of help to design practitioners for the sizing of borehole arrays for both heating and cooling. Design and performance matching to a wide variety of HVAC combinations, building energy demand levels and two contrasting sets of earth thermal property data are included so that practitioners will be able to select results that suit a range of modern applications. Also included are results of 10-year energy simulations that demonstrate the required design and operating conditions needed to ensure that initial undisturbed earth conditions will not drift with time to an unacceptable extent. Comparisons are made with conventional heating and cooling methods so that estimates of carbon savings due to the use of ground-coupled heat pumps with (and without) direct cooling can be made

The Galactic Center Black Hole Laboratory

The super-massive 4 million solar mass black hole Sagittarius~A* (SgrA*) shows flare emission from the millimeter to the X-ray domain. A detailed analysis of the infrared light curves allows us to address the accretion phenomenon in a statistical way. The analysis shows that the near-infrared flare amplitudes are dominated by a single state power law, with the low states in SgrA* limited by confusion through the unresolved stellar background. There are several dusty objects in the immediate vicinity of SgrA*. The source G2/DSO is one of them. Its nature is unclear. It may be comparable to similar stellar dusty sources in the region or may consist predominantly of gas and dust. In this case a particularly enhanced accretion activity onto SgrA* may be expected in the near future. Here the interpretation of recent data and ongoing observations are discussed.Comment: 30 pages - 7 figures - accepted for publication by Springer's "Fundamental Theories of Physics" series; summarizing GC contributions of 2 conferences: 'Equations of Motion in Relativistic Gravity' at the Physikzentrum Bad Honnef, Bad Honnef, Germany, (Feb. 17-23, 2013) and the COST MP0905 'The Galactic Center Black Hole Laboratory' Granada, Spain (Nov. 19 - 22, 2013

Phase I study to determine the safety, tolerability and immunostimulatory activity of thalidomide analogue CC-5013 in patients with metastatic malignant melanoma and other advanced cancers

We assessed the safety, tolerability and efficacy of the immunomodulatory drug, CC-5013 (REVIMID(TM)), in the treatment of patients with metastatic malignant melanoma and other advanced cancers. A total of 20 heavily pretreated patients received a dose-escalating regimen of oral CC-5013. Maximal tolerated dose, toxicity and clinical responses were evaluated and analysis of peripheral T-cell surface markers and serum for cytokines and proangiogenic factors were performed. CC-5013 was well tolerated. In all, 87% of adverse effects were classified as grade 1 or grade 2 according to Common Toxicity Criteria and there were no serious adverse events attributable to CC-5013 treatment. Six patients failed to complete the study, three because of disease progression, two withdrew consent and one was entered inappropriately and withdrawn from the study. The remaining 14 patients completed treatment without dose reduction, with one patient achieving partial remission. Evidence of T-cell activation was indicated by significantly increased serum levels of sIL-2 receptor, granulocyte- macrophage colony-stimulating factor, interleukin-12 (IL-12), tumour necrosis factor-alpha and IL-8 in nine patients from whom serum was available. However, levels of proangiogenic factors vascular endothelial growth factor and basic foetal growth factor were not consistently affected, This study demonstrates the safety, tolerability and suggests the clinical activity of CC-5013 in the treatment of refractory malignant melanoma. Furthermore, this is the first report demonstrating T-cell stimulatory activity of this class of compound in patients with advanced cancer

Numerical Analysis of the Thermo-mechanical Behavior of Energy Piles

A finite element model is developed to investigate the thermomechanical behavior of the energy pile in detail. In the model, soil is regarded as a kind of thermo-elastic-perfectly plastic material, and the interaction between the pile and soil is modeled by contact elements. In order to save the computing time, the U-tubes in the energy pile are simulated by line elements, which are proved to be suitable for calculating the temperature of the pile. To deal with the thermomechanical multi-field problem, the sequential coupling method is utilized. The simulation results show that the thermally induced stress and deformation in the pile can be significantly influenced by the properties of the soil, the applied mechanical load and the restraint condition at the pile head. Long-time simulations of the energy pile with cyclic heat injections and extractions indicate that the thermal cycles would induce an unrecoverable settlement of the pile, and the ultimate bearing capacity of the energy pile may need to be redefined in view of its longtime performance.Department of Building Services Engineerin