Reducing GHGs from UK Households ‐ An Examination of Local Authority‐Level Data

As the threat of irreversible climate change has increased over time, the UK has focused on reducing its carbon emission levels. International treaties such as the Kyoto Protocol have informed national targets, directing the UK in reducing its climate impact. In order to achieve this an understanding of the factors that affect carbon emission reductions is vital. Identifying what dictates the success of UK local authorities in reducing their carbon emissions addresses this problem. The research uses secondary data regarding local authorities’ carbon emissions and regression analyses to explore the key factors affecting domestic emission levels over time. The research goes into further detail than existing literature through exploring sources of emissions across different sectors and analysing emissions reductions specifically between 2005-2016. Substantial and relatively consistent domestic emissions reductions were achieved in this time frame, exceeding the reductions provided by decarbonisation of the electricity grid. Standard deviations of 3% were observed in this sector, compared with 12% from Industrial & Commercial emissions. While population density demonstrated a statistically significant correlation with domestic GHG reductions, gross disposable household income was not found to be significant; however, it is a relevant indicator of total emissions levels in 2016. Through identifying these factors, suggestions to local government are made such as the implementation of region-specific strategies, tailoring these to the exact characteristics of a local authority. Furthermore, consideration of population density in conjunction with domestic and urban planning will allow for future emissions reductions to occur across the UK

Analysis of greenhouse gas mitigation performance in UK urban areas

As the threat of irreversible climate change has increased over time, the UK has continued to set increasingly ambitious policies to reduce its carbon emission. An assessment of mitigation progress to date at the local authority level clarifies the factors that have affected greenhouse gas (GHG) emissions on the path to carbon neutrality. This research uses regression analyses between local authorities’ GHG emission redcutions and selected explanatory variables (including population density, household income, and manufacturing employment) identified from the literature to explore mitigation performance over time, focusing on GHG emissions changes between 2005 and 2016. Substantial and relatively consistent GHG emissions reductions were achieved in this time frame, with average total reductions across UK local authorities of 31.2%. Population density was moderately-to-strongly correlated with the success of transportation GHG emissions mitigation, though this sector has seen the smallest percentage declines over this period. Local authorities with densities below 25 inhabitants per hectare were generally among the poorest performers in transportation GHG mitigation. This underscores the need to support remote working and electrification of personal transportation in areas where public/active transportation options are not viable alternatives. Furthermore, consideration of population density in conjunction with domestic and urban planning will allow for future emissions reductions to occur across the UK. Fundamentally, GHG emissions reductions to date are largely driven by historic factors (density), shifting economic structures (deindustrialisation), and centralised initiatives (decarbonisation of electricity generation)

Leading quantum gravitational corrections to QED

We consider the leading post-Newtonian and quantum corrections to the non-relativistic scattering amplitude of charged spin-1/2 fermions in the combined theory of general relativity and QED. The coupled Dirac-Einstein system is treated as an effective field theory. This allows for a consistent quantization of the gravitational field. The appropriate vertex rules are extracted from the action, and the non-analytic contributions to the 1-loop scattering matrix are calculated in the non-relativistic limit. The non-analytical parts of the scattering amplitude are known to give the long range, low energy, leading quantum corrections, are used to construct the leading post-Newtonian and quantum corrections to the two-particle non-relativistic scattering matrix potential for two massive fermions with electric charge.Comment: 14 pages, 29 figures, format RevTex

Effect of maternal cold exposure and nutrient restriction on insulin-like growth factor sensitivity in adipose tissue of newborn sheep

Adipose tissue mass in the newborn is determined in part by insulin-like growth factor (IGF)s, which are dependent on the maternal nutritional and metabolic environment during late gestation. The present study was designed to determine whether maternal cold exposure (CE) commencing in mid gestation could modulate some of the adaptive effects of nutrient restriction in late gestation on adipose tissue endocrine sensitivity in the resulting offspring. Twenty eight pregnant sheep were entered into the study and were either shorn, i.e. cold exposed, from 70 days gestation (term = 147 days), or remained unshorn, and were fed either their total calculated metabolisable energy (ME) requirements for body weight and pregnancy from 110 days gestation or 50% of this amount (n=7 per group). Adipose tissue was sampled from the offspring at one day of age and the mRNA abundance for IGF-I, II their receptors (R) and GH secretagogue receptor-1a (GHSR-1a) were determined. CE mothers produced larger offspring with more perirenal adipose tissue, an adaptation prevented by maternal nutrient restriction. Nutrient restriction in unshorn mothers increased IGF-I and IIR mRNA abundance. The mRNA abundances for IGF-I, II and IIR in adipose tissue were reduced by CE, adaptations independent of maternal food intake, whereas CE plus nutrient restriction increased GHSR-1a mRNA. In conclusion, maternal nutrient restriction with or without CE has very different effects on IGF sensitivity of adipose tissue and may act to ensure adequate fat stores are present in the newborn in the face of very different maternal endocrine and metabolic environments

Jet-Induced Nucleosynthesis in Misaligned Microquasars

The jet axes and the orbital planes of microquasar systems are usually assumed to be approximately perpendicular, eventhough this is not currently an observational requirement. On the contrary, in one of the few systems where the relative orientations are well-constrained, V4641Sgr, the jet axis is known to lie not more than ~36 degrees from the binary plane. Such a jet, lying close to the binary plane, and traveling at a significant fraction of the speed of light may periodically impact the secondary star initiating nuclear reactions on its surface. The integrated yield of such nuclear reactions over the age of the binary system (less the radiative mass loss) will detectably alter the elemental abundances of the companion star. This scenario may explain the anomalously high Li enhancements (roughly ~20-200 times the sun's photospheric value; or, equivalently, 0.1-1 times the average solar system value) seen in the companions of some black-hole X-ray binary systems. (Such enhancements are puzzling since Li nuclei are exceedingly fragile - being easily destroyed in the interiors of stars - and Li would be expected to be depleted rather than enhanced there.) Gamma-ray line signatures of the proposed process could include the 2.22 MeV neutron capture line as well as the 0.478 MeV 7Li* de-excitation line, both of which may be discernable with the INTEGRAL satellite if produced in an optically thin region during a large outburst. For very energetic jets, a relatively narrow neutral pion gamma-decay signature at 67.5 MeV could also be measurable with the GLAST satellite. We argue that about 10-20% of all microquasar systems ought to be sufficiently misaligned as to be undergoing the proposed jet-secondary impacts.Comment: ApJ, accepted. Includes referee's suggestions and some minor clarifications over previous versio

Cost-effectiveness of age-related macular degeneration study supplements in the UK: combined trial and real-world outcomes data

Aims To evaluate the cost-effectiveness of Age-Related Eye Disease Study (AREDS) 1 & 2 supplements in patients with either bilateral intermediate age-related macular degeneration, AREDS category 3, or unilateral neovascular age-related macular degeneration AMD (nAMD), AREDS category 4. Methods A patient-level health state transition model based on levels of visual acuity in the better-seeing eye was constructed to simulate the costs and consequences of patients taking AREDS vitamin supplements. Setting: UK National Health Service (NHS). The model was populated with data from AREDS and real-world outcomes and resource use from a prospective multicentre national nAMD database study containing 92 976 ranibizumab treatment episodes. Interventions Two treatment approaches were compared: immediate intervention with AREDS supplements or no supplements. Main outcome measures: quality-adjusted life years (QALYs) and healthcare costs were accrued for each strategy, and incremental costs and QALYs were calculated for the lifetime of the patient. One-way and probabilistic sensitivity analyses were employed to test the uncertainty of the model. Results For AREDS category 3, the incremental cost-effectiveness ratio was £30 197. For AREDS category 4 compared with no intervention, AREDS supplements are more effective (10.59 vs 10.43 QALYs) and less costly (£52 074 vs 54 900) over the lifetime of the patient. Conclusions The recommendation to publicly fund AREDS supplements to category 3 patients would depend on the healthcare system willingness to pay. In contrast, initiating AREDS supplements in AREDS category 4 patients is both cost saving and more effective than no supplement use and should therefore be considered in public health policy

Optical photometric GTC/OSIRIS observations of the young massive association Cygnus OB2

In order to fully understand the gravitational collapse of molecular clouds, the star formation process and the evolution of circumstellar disks, these phenomena must be studied in different Galactic environments with a range of stellar contents and positions in the Galaxy. The young massive association Cygnus OB2, in the Cygnus-X region, is an unique target to study how star formation and the evolution of circumstellar disks proceed in the presence of a large number of massive stars. We present a catalog obtained with recent optical observations in r,i,z filters with OSIRIS, mounted on the $10.4\,m$ GTC telescope, which is the deepest optical catalog of Cyg OB2 to date. The catalog consist of 64157 sources down to M=0.15 solar masses at the adopted distance and age of Cyg OB2. A total of 38300 sources have good photometry in all three bands. We combined the optical catalog with existing X-ray data of this region, in order to define the cluster locus in the optical diagrams. The cluster locus in the r-i vs. i-z diagram is compatible with an extinction of the optically selected cluster members in the 2.64<AV<5.57 range. We derive an extinction map of the region, finding a median value of AV=4.33 in the center of the association, decreasing toward the north-west. In the color-magnitude diagrams, the shape of the distribution of main sequence stars is compatible with the presence of an obscuring cloud in the foreground at about 850+/-25 pc from the Sun.Comment: Accepted for publication ApJS 201

A systematic review of risk assessment tools for contaminated sites – Current perspectives and future prospects

© 2020 Elsevier Inc. Health and safety hazards associated with the redevelopment of contaminated sites can be complex and pose considerable risks. A systematic literature review was conducted on risk assessment tools for contaminated sites. These tools have been identified from searching through leading academic databases and other professional sources. For each of the identified tools the relevant risk assessment stages, harm type, hazard category, receptor type and pathways are reported. Findings reveal that despite growing interest in the development of risk assessment tools, there are persistent knowledge gaps identified in this study, which serve as a basis for future research direction to where more advanced practical tools could be invented. For instance, it is evidenced there is a shortfall in practical tools available to contaminated site assessors conducting investigations at the preliminary risk assessment stage. Addressing this opening can benefit the planning process, coordinated between relevant stakeholders and, moreover, reduce uncertainty in the decision-making of contaminated site developers

Waiting in the Wings: Reflected X-ray Emission from the Homunculus Nebula

We report the first detection of X-ray emission associated with the Homunculus Nebula which surrounds the supermassive star Eta Carinae. The emission is characterized by a temperature in excess of 100 MK, and is consistent with scattering of the time-delayed X-ray flux associated with the star. The nebular emission is bright in the northwestern lobe and near the central regions of the Homunculus, and fainter in the southeastern lobe. We also report the detection of an unusually broad Fe K fluorescent line, which may indicate fluorescent scattering off the wind of a companion star or some other high velocity outflow. The X-ray Homunculus is the nearest member of the small class of Galactic X-ray reflection nebulae, and the only one in which both the emitting and reflecting sources are distinguishable.Comment: 17 pages, 5 figures, accepted by Ap