Measurements of the light-absorbing material inside cloud droplets and its effect on cloud albedo

Most of the measurements of light-absorbing aerosol particles made previously have been in non-cloudy air and therefore provide no insight into aerosol effects on cloud properties. Here, researchers describe an experiment designed to measure light absorption exclusively due to substances inside cloud droplets, compare the results to related light absorption measurements, and evaluate possible effects on the albedo of clouds. The results of this study validate those of Twomey and Cocks and show that the measured levels of light-absorbing material are negligible for the radiative properties of realistic clouds. For the measured clouds, which appear to have been moderately polluted, the amount of elemental carbon (EC) present was insufficient to affect albedo. Much higher contaminant levels or much larger droplets than those measured would be necessary to significantly alter the radiative properties. The effect of the concentrations of EC actually measured on the albedo of snow, however, would be much more pronounced since, in contrast to clouds, snowpacks are usually optically semi-infinite and have large particle sizes

Will Brexit raise the cost of living?

This paper considers two aspects of this question. First, Brexit has already induced a devaluation of sterling of around 14 per cent since June 2016, which has started to work through to consumer prices: between June 2016 and July 2017 consumer prices increased by around 2.5 per cent. Second, while it is not government policy, nor the desire of the UK public, that the outcome of negotiations is a ‘MFN Brexit’, this remains a distinct possibility. Thus we ask how the imposition of tariffs on imports from the EU will work through into consumer prices. Making very conservative assumptions, we conclude that ‘MFN Brexit’ will increase the average cost of living by around 1 per cent and increase it for 8 per cent of households by 2 per cent or more. We present results for different groups of households according to their employment and structural characteristics and show that the impact will generally be largest on unemployed, single parent and pensioner households

Digital mammography, cancer screening: Factors important for image compression

The use of digital mammography for breast cancer screening poses several novel problems such as development of digital sensors, computer assisted diagnosis (CAD) methods for image noise suppression, enhancement, and pattern recognition, compression algorithms for image storage, transmission, and remote diagnosis. X-ray digital mammography using novel direct digital detection schemes or film digitizers results in large data sets and, therefore, image compression methods will play a significant role in the image processing and analysis by CAD techniques. In view of the extensive compression required, the relative merit of 'virtually lossless' versus lossy methods should be determined. A brief overview is presented here of the developments of digital sensors, CAD, and compression methods currently proposed and tested for mammography. The objective of the NCI/NASA Working Group on Digital Mammography is to stimulate the interest of the image processing and compression scientific community for this medical application and identify possible dual use technologies within the NASA centers

Robustness of superconductivity to competing magnetic phases in tetragonal FeS

We have determined the superconducting and magnetic properties of a hydrothermally synthesized powder sample of tetragonal FeS using muon spin rotation ({\mu}SR). The superconducting properties are entirely consistent with those of a recently published study, showing fully gapped behavior and giving a penetration depth of {\lambda}_{ab} = 204(3) nm. However, our zero-field {\mu}SR data are rather different and indicate the presence of a small, non-superconducting magnetic phase within the sample. These results highlight that sample-to-sample variations in magnetism can arise in hydrothermally prepared phases, but interestingly the superconducting behavior is remarkably insensitive to these variations.Comment: 5 pages, 2 figure

Control via electron count of the competition between magnetism and superconductivity in cobalt and nickel doped NaFeAs

Using a combination of neutron, muon and synchrotron techniques we show how the magnetic state in NaFeAs can be tuned into superconductivity by replacing Fe by either Co or Ni. Electron count is the dominant factor, since Ni-doping has double the effect of Co-doping for the same doping level. We follow the structural, magnetic and superconducting properties as a function of doping to show how the superconducting state evolves, concluding that the addition of 0.1 electrons per Fe atom is sufficient to traverse the superconducting domain, and that magnetic order coexists with superconductivity at doping levels less than 0.025 electrons per Fe atom.Comment: 4 pages, 6 figure

Approximate probabilistic verification of hybrid systems

Hybrid systems whose mode dynamics are governed by non-linear ordinary differential equations (ODEs) are often a natural model for biological processes. However such models are difficult to analyze. To address this, we develop a probabilistic analysis method by approximating the mode transitions as stochastic events. We assume that the probability of making a mode transition is proportional to the measure of the set of pairs of time points and value states at which the mode transition is enabled. To ensure a sound mathematical basis, we impose a natural continuity property on the non-linear ODEs. We also assume that the states of the system are observed at discrete time points but that the mode transitions may take place at any time between two successive discrete time points. This leads to a discrete time Markov chain as a probabilistic approximation of the hybrid system. We then show that for BLTL (bounded linear time temporal logic) specifications the hybrid system meets a specification iff its Markov chain approximation meets the same specification with probability $1$. Based on this, we formulate a sequential hypothesis testing procedure for verifying -approximately- that the Markov chain meets a BLTL specification with high probability. Our case studies on cardiac cell dynamics and the circadian rhythm indicate that our scheme can be applied in a number of realistic settings

Boosting soil literacy in schools can help improve understanding of soil/human health linkages in Generation Z

Soil health underpins ecosystem services like food security and therefore underpins human health. Poor soil health is a global problem which is hindering attempts to deliver the UN’s Sustainable Development Goals. We focus on goals 3 (human health), 13 (climate change) which are intimately linked to goal 15 (soil health). Soil health is arguably most fragile in regions such as sub-Saharan Africa (SSA) where aged soils are characterised by poor nutrient and water holding capacity, and are largely deficient in micronutrients such as Zinc. Poor soil health coupled with the largely cereal-based diets can mean that micronutrient malnutrition is high in the region. In sub-Saharan Africa, where much of the population is too poor to purchase mineral supplements, poor soil health (SDG15) can therefore negatively impact on human health (SDG3). We surveyed 3661 school children aged 13–15 in three African countries, Ghana, South Africa and Zimbabwe, for their ‘Attitudes, Behaviours and Competencies’ of soil, which we termed ‘ABC’. The ‘ABC’ survey results showed significant soil illiteracy. The survey showed that although students were generally equipped with a good attitude to (overall 52% positive) and behaviour towards soil (overall 60% engagement), they had little competency as to how to improve soil health (overall 23% knowledge). For example, less than 35% of respondents across all countries know that soil is living. Less than 13% of students are aware of the important role of soil in climate change mitigation. We believe that these two knowledge gaps must be addressed for Generation Z to understand the important linkages between climate change, soil and human health. We propose a hands-on ‘ethics of care’ approach to engage society with soil, piggybacking on existing climate change educational resources by building terrariums with living soil can empower children to learn about soil, plant, human and planetary health. The future of food security depends on Generation Z having soil literacy. Our survey clearly shows that students who think farming is a good way to make money have significantly higher levels of overall soil literacy. We propose that the future of human health depends on soil literacy

Supramolecular self-assembled network formation containing N···Br halogen bonds in physisorbed overlayers.

The formation of a halogen bonded self-assembled co-crystal physisorbed monolayer containing N···Br interactions is reported for the first time. The co-crystal monolayer is identified experimentally by synchrotron X-ray diffraction and the structure determined. Density functional theory (DFT) calculations are also employed to assess the magnitudes of the different interactions in the layer. Significantly, compared to other halogen bonds in physisorbed monolayers we have reported recently, the N···Br bond here is found to be non-linear. It is proposed that the increasing importance of the lateral hydrogen bond interactions, relative to the halogen bond strength, leads to the bending of the halogen bonds.We acknowledge financial support for AB from EPSRC DTA award from the Department of Chemistry, University of Cambridge. We acknowledge Diamond Light Source for time on beamline I11 under proposals EE6511 and EE7761.This is the final version of the article. It first appeared from the Royal Society of Chemistry via http://dx.doi.org/10.1039/C4CP03379

Domestic ventilation rates, indoor humidity and dust mite allergens : are our homes causing the asthma pandemic?

This paper is concerned with historical changes in domestic ventilation rates, relative humidity and the associated risk of house dust mite colonization. A controlled trial evaluated allergen and water vapour control measures on the level of house dust mite (HDM) Der p1 allergen and indoor humidity, concurrently with changes in lung function in 54 subjects who completed the protocol. Mechanical heat recovery ventilation units significantly reduced moisture content in the active group, while HDM allergen reservoirs in carpets and beds were reduced by circa 96%. Self reported health status confirmed a significant clinical improvement in the active group. The study can form the basis for assessing minimum winter ventilation rates that can suppress RH below the critical ambient equilibrium humidity of 60% and thus inhibit dust mite colonization and activity in temperate and maritime in' uenced climatic regions