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It is a remarkable fact that we do not know what the vast majority of the universe is made of. Everything we can see, planets, stars, galaxies, and gas, makes up just a tiny fraction of the matter in the universe. The rest, invisible to us, was dubbed “dark matter” by Fritz Zwicky, the maverick but brilliant astronomer, rocket scientist, and humanitarian, who inferred its existence when trying to reconcile the motions of galaxies with the laws of gravity [1]. More recent astronomical observations, probing the universe at many scales and wavelengths, point to the same conclusion [2]. Now, almost 80 years later, dark matter, and its partner dark energy, are the pervasive dogma of cosmology. At the other extreme of scale, another mystery is presented by the great variety of fundamental particles, for which we have little understanding of why such diversity exists. Theories of “physics beyond the standard model” may provide some of the answers. One of their most robust predictions is of a new fundamental particle [3], produced in abundance in the Big Bang, which will be hard, but not quite impossible, to detect. It is not surprising, therefore, that proof of the existence of these elusive particles, with the fundamental impact that discovery would bring to both physics and astronomy, has become one of the most prized of all goals in science. The science facility at Boulby Mine has been at the heart of this research for the last two decades. [ABSTRACT FROM PUBLISHER]

Abstract: Ion-induced nucleation has been studied in a deep underground ultra-low background radiation environment where the role of ions can be distinguished from alternative neutral aerosol nucleation mechanisms. Our results demonstrate that ions have a significant effect on the production of small sulfuric acid–water clusters over a range of sulfuric acid concentrations although neutral nucleation mechanisms remain evident at low ionization levels. The effect of ions is found both to enhance the nucleation rate of stable clusters and the initial growth rate. The effects of possible contaminations are also discussed and are believed to be small, but cannot be excluded. If our results can be extrapolated to conditions that resemble the clean air atmosphere over the Earth''s oceans they suggest that ions may dominate the production of small (4nm) aerosols here. [Copyright &y& Elsevier]

The article focuses on the Boulby International Subsurface Astrobiology Laboratory (BISAL) in Saltburn-on-the-Sea in North Yorkshire, England. Topics discussed include BISAL's concentration on in-situ deep subsurface astrobiology and space technology development, its location in the Boulby potash mine, and the study of environments with analogues to the planet Mars. Also mentioned are capabilities to be provided for the study of the Earth's biosphere and the testing of space technology.

Polygonal features in a ∼250 million-year-old Permian evaporitic deposit were investigated for their geological and organic content to test the hypothesis that they could preserve the signature of ancient habitable conditions and biological activity. Investigations on evaporitic rock were carried out as part of the MIne Analog Research (MINAR) project at Boulby Mine, the United Kingdom. The edges of the polygons have a higher clay content and contain higher abundances of minerals such as quartz and microcline, and clays such as illite and chlorite, compared with the interior of polygons, suggesting that the edges were preferred locations for the accumulation of weathering products during their formation. The mineral content and its strontium isotope ratio suggest that the material is from continental weathering at the borders of the Permian Zechstein Sea. The edges of the polygons contain material with mean δ13C and δ15N values of −20.8 and 5.3, respectively. Lipids, including alkanes and hopanes, were extracted from the interior and edges of the polygons, which are inferred to represent organic material entrained in the evaporites when they were formed. The presence of long-chain alkanes (C20–C35) that lack a carbon preference, low abundances of C23–C29 hopanes, and lack of marine, evaporitic, or thermal maturity indicators show that lipid biomarkers were, at least in part, potentially derived from a continental source and have not undergone significant thermal maturation since deposition. Lipid extractions using weak acids revealed significantly more lipids than those without acid, potentially indicating that encapsulation was not the only type of preservation mechanism occurring in Boulby salts. These data demonstrate the potential for ancient evaporites and their polygons to preserve information on local geological conditions, ancient habitability, and evidence of life. The data show that analogous martian evaporitic deposits are good targets for future life detection missions and the investigation of ancient martian habitability. [ABSTRACT FROM AUTHOR]

Carbon capture and storage is a transition technology from a past and present fuelled by coal, oil and gas and a planned future dominated by renewable energy sources. The technology involves the capture of carbon dioxide emissions from fossil fuel power stations and other point sources, compression of the CO2 into a fluid, transporting it and injecting it deep beneath the Earth’s surface into depleted petroleum reservoirs and other porous formations. Once injected, the CO2 must be monitored to ensure that it is emplaced and assimilated as planned and that none leaks back to surface. A variety of methods have been deployed to monitor the CO2 storage site and many such methods have been adapted from oilfield practice. However, such methods are commonly indirect, episodic, require active signal generation and remain expensive throughout the monitoring period that may last for hundreds of years. A modelling framework was developed to concurrently simulate CO2 geostorage conditions and background cosmic-ray muon tomography, in which the potential was assessed for using variations in muon attenuation, due to changes in CO2 abundance, as a means of CO2 detection. From this, we developed a passive, continuous monitoring method for CO2 storage sites using muon tomography, the tools for which can be deployed during the active drilling phase (development) of the storage site. To do this, it was necessary to develop a muon detector that could be used in the hostile environment (saline, high temperature) of the well bore. A prototype detector has been built and tested at the 1.1 km deep Boulby potash mine on the northeast coast of England, supported by the existing STFC Boulby Underground Laboratory on the site. The detector is now ready to be commercialized. [ABSTRACT FROM AUTHOR]

Charles S Cockell, Samuel Payler, Sean Paling and Dave McLuckie outline plans for the first underground astrobiology facility.Charles S Cockell, Samuel Payler, Sean Paling and Dave McLuckie outline plans for the first underground astrobiology facility. [ABSTRACT FROM AUTHOR]

Quinuclidinyl benzilate (QNB) and its derivatives are being developed to investigate muscarinic receptor changes in vivo in Alzheimer''s disease and dementia with Lewy bodies. This is the first study of [125I]-(R,R)-I-QNB and [125I]-(R,S)-I-QNB binding in vitro in human brain. We have compared the in vitro binding of the muscarinic ligands [3H]pirenzepine and [3H]AF-DX 384, which have selectivity for the M1 and M2/M4 receptor subtypes, respectively, to the binding of [125I]-(R,R)-I-QNB and [125I]-(R,S)-I-QNB. This will provide a guide to the interpretation of in vivo SPET images generated with [123I]-(R,R)-I-QNB and [123I]-(R,S)-I-QNB. Binding was investigated in striatum, globus pallidus, thalamus and cerebellum, and cingulate, insula, temporal and occipital cortical areas, which show different proportions of muscarinic receptor subtypes, in post-mortem brain from normal individuals. M1 receptors are of high density in cortex and striatum and are relatively low in the thalamus and cerebellum, while M4 receptors are mainly expressed in the striatum, and M2 receptors are most evident in the cerebellum and thalamus. [125I]-(R,R)-I-QNB and [125I]-(R,S)-I-QNB density distribution patterns were consistent with binding to both M1 and M4 receptors, with [125I]-(R,R)-I-QNB additionally binding to a non-cholinergic site not displaceable by atropine. This distribution can be exploited by in vivo imaging, developing ligands for both SPET and PET, to reveal muscarinic receptor changes in Alzheimer''s disease and dementia with Lewy bodies during the disease process and following cholinergic therapy. [Copyright &y& Elsevier]

Differences in regional cerebral blood flow (rCBF) between subjects with Alzheimer's disease (AD), dementia with Lewy bodies (DLB) and healthy volunteers were investigated using statistical parametric mapping (SPM99). Forty-eight AD, 23 DLB and 20 agematched control subjects participated. Technetium-99m hexamethylpropylene amine oxime (HMPAO) brain single-photon emission tomography (SPET) scans were acquired for each subject using a single-headed rotating gamma camera (IGE CamStar XR/T). The SPET images were spatially normalised and group comparison was performed by SPM99. In addition, covariate analysis was undertaken on the standardised images taking the Mini Mental State Examination (MMSE) scores as a variable. Applying a height threshold of P≤ 0.001 uncorrected, significant perfusion deficits in the parietal and frontal regions of the brain were observed in both AD and DLB groups compared with the control subjects. In addition, significant temporoparietal perfusion deficits were identified in the AD subjects, whereas the DLB patients had deficits in the occipital region. Comparison of dementia groups (height threshold of P≤0.01 uncorrected) yielded hypoperfusion in both the parietal [Brodmann area (BA) 7] and occipital (BA 17, 18) regions of the brain in DLB compared with AD. Abnormalities in these areas, which included visual cortex and several areas involved in higher visual processing and visuospatial function, may be important in understanding the visual hallucinations and visuospatial deficits which are characteristic of DLB. Covariate analysis indicated group differences between AD and DLB in terms of a positive correlation between cognitive test score and temporoparietal blood flow. In conclusion, we found evidence of frontal and parietal hypoperfusion in both AD and DLB, while temporal perfusion deficits were observed exclusively in AD and parieto-occipital deficits in DLB. [ABSTRACT FROM AUTHOR]

This paper explores the prospect of CMOS devices to assay lead in drinking water, using calorimetry. Lead occurs together with traces of radioisotopes, e.g., 210 Pb , producing γ -emissions with energies ranging from 10 k e V to several 100 k e V when they decay; this range is detectable in silicon sensors. In this paper we test a CMOS camera (Oxford Instruments Neo 5.5) for its general performance as a detector of X-rays and low energy γ -rays and assess its sensitivity relative to the World Health Organization upper limit on lead in drinking water. Energies from 6 k e V to 60 k e V are examined. The CMOS camera has a linear energy response over this range and its energy resolution is for the most part slightly better than 2%. The Neo sCMOS is not sensitive to X-rays with energies below ∼ 10   k e V . The smallest detectable rate is 40 ± 3 m Hz , corresponding to an incident activity on the chip of 7 ± 4 Bq. The estimation of the incident activity sensitivity from the detected activity relies on geometric acceptance and the measured efficiency vs. energy. We report the efficiency measurement, which is 0.08(2)% (0.0011(2)%) at 26.3 k e V ( 59.5 k e V ). Taking calorimetric information into account we measure a minimal detectable rate of 4 ± 1 m Hz ( 1.5 ± 1 m Hz) for 26.3 k e V ( 59.5 k e V ) γ -rays, which corresponds to an incident activity of 1.0 ± 6 Bq ( 57 ± 33 Bq). Toy Monte Carlo and Geant4 simulations agree with these results. These results show this CMOS sensor is well-suited as a γ - and X-ray detector with sensitivity at the few to 100 ppb level for 210 Pb in a sample. [ABSTRACT FROM AUTHOR]