Symmetries of quasiplatonic Riemann surfaces

We state and prove a corrected version of a theorem of Singerman, which relates the existence of symmetries (anticonformal involutions) of a quasiplatonic Riemann surface $\mathcal S$ (one uniformised by a normal subgroup $N$ of finite index in a cocompact triangle group $\Delta$) to the properties of the group $G=\Delta/N$. We give examples to illustrate the revised necessary and sufficient conditions for the existence of symmetries, and we relate them to properties of the associated dessins d'enfants, or hypermaps

Baited remote underwater survey of chondrichthyans in False Bay, South Africa

Worldwide, numerous shark populations are in rapid decline due to chronic overfishing. Their slow reproductive capacity make them susceptible to extinction. To monitor the status of chondrichthyan species, the method or combination of methods used should be non-selective, applicable in a variety of habitats and under most environmental conditions. Baited Remote Underwater Video (BRUV) surveys have shown major benefits over traditional capture-based survey methods in multiple areas. They have been shown to be non-extractive, causing no major disturbance to the substrata and its epibenthos. Large, mobile animals that avoid divers and active fishing surveys are detected. The recorded video removes the need for specialist observers to conduct all the fieldwork. The video allows impartial and repeatable measurements and standardizes data collection and training in association with remote taxonomists. The method is also cheaper than alternatives. Ninety-five sites were sampled with 60 minute video recordings across the whole of False Bay during the period of June-July 2012. Fifteen species of chondrichthyans were recorded, of which Haploblepharus edwardsii was the most abundant, being observed at 83 of 95 sites. One hour was sufficient to capture all the chondrichthyans within the observed area as the average time of arrival was about half an hour into the recording. The distribution of the chondrichthyan population was remarkably uniform across the bay. Depth, habitat and substrate type were significant predictors of species composition (P = 0.004, 0.025 and 0.001 respectively). Opportunistic encounters (one individual observed) included Carcharodon carcharias, Squalus megalops, Rhinobatos annulatus and Myliobatis aquila

Metabolomic profiling and stable isotope labelling of Trichomonas vaginalis and Tritrichomonas foetus reveal major differences in amino acid metabolism including the production of 2-hydroxyisocaproic acid, cystathionine and S-methylcysteine

Trichomonas vaginalis and Tritrichomonas foetus are pathogens that parasitise, respectively, human and bovine urogenital tracts causing disease. Using LC-MS, reference metabolomic profiles were obtained for both species and stable isotope labelling with D-[U-13C6] glucose was used to analyse central carbon metabolism. This facilitated a comparison of the metabolic pathways of T. vaginalis and T. foetus, extending earlier targeted biochemical studies. 43 metabolites, whose identities were confirmed by comparison of their retention times with authentic standards, occurred at more than 3-fold difference in peak intensity between T. vaginalis and T. foetus. 18 metabolites that were removed from or released into the medium during growth also showed more than 3-fold difference between the species. Major differences were observed in cysteine and methionine metabolism in which homocysteine, produced as a bi-product of trans-methylation, is catabolised by methionine γ-lyase in T. vaginalis but converted to cystathionine in T. foetus. Both species synthesise methylthioadenosine by an unusual mechanism, but it is not used as a substrate for methionine recycling. T. vaginalis also produces and exports high levels of S-methylcysteine, whereas only negligible levels were found in T. foetus which maintains significantly higher intracellular levels of cysteine. 13C-labeling confirmed that both cysteine and S-methylcysteine are synthesised by T. vaginalis; S-methylcysteine can be generated by recombinant T. vaginalis cysteine synthase using phosphoserine and methanethiol. T. foetus contained higher levels of ornithine and citrulline than T. vaginalis and exported increased levels of putrescine, suggesting greater flux through the arginine dihydrolase pathway. T. vaginalis produced and exported hydroxy acid derivatives of certain amino acids, particularly 2-hydroxyisocaproic acid derived from leucine, whereas negligible levels of these metabolites occurred in T. foetus

Co-occurrence of Sympatric Poroderma Species

Species exploiting similar ecological niches are expected to adapt their behaviour, which can either promote or hinder coexistence. This study examined the ecological (dis)similarity between the endemic Poroderma africanum (pyjama catshark) and Poroderma pantherinum (leopard catshark) in Mossel Bay, South Africa. The co-occurrence of these species was examined along the ecological axes of time, trophic position and space, between October 2015 and April 2018, through the use of Baited Remote Underwater Videos (BRUV), gastric lavage, and acoustic telemetry. Through the deployment of 197 BRUVs, P. africanum showed a seasonal, higher Relative Abundance (RA = 0.52), occurring more frequently during winter months, while showing an overall decline in RA over the course of the study period. Poroderma pantherinum on the other hand, showed a lower, unseasonal RA (0.20), remaining relatively stable throughout the study period. The BRUV deployments indicated that the two species showed a positive co-occurrence with one other, being sighted in BRUV deployments more frequently together as opposed to in isolation/at random. Acoustic telemetry indicated that the two species were active during different diel periods, influenced by a complex combination of tidal and diel rhythms, while P. pantherinum showed a higher residency compared to P. africanum (P. pantherinum: Continuous Residency Time (CRT)24 = 3.32 days (mean), 95% CI: 2.53–4.11 days; P. africanum: CRT24 = 2.01 days, 95% CI: 1.66–2.36 days). While the two species are sympatric in nature, and have an overlapping, endemic, distribution, acoustic telemetry indicated that 1 ABSTRACT P. africanum showed higher degrees of movement throughout the acoustic receiver array (P. africanum: edge density (ED) = 0.25; P. pantherinum: ED = 0.12); however, certain areas of the bay showed to be of high importance for both species. Both species revealed high levels of intra- and inter-specific variation in both residency and movement behaviour. Gastric lavage indicated partially overlapping trophic niches, between the two Poroderma spp. Poroderma africanum had a generalist diet, dominated by teleosts (Index of Relative Importance (IRI)% = 22.69), octopus (IRI% = 11.48) and discarded bait (IRI% = 64.54), while P. pantherinum showed indications of being a specialist predator, with a diet dominated by cephalopods (IRI% = 83.68). The two Poroderma spp. showed a partially overlapping, but separate trophic niches, while displaying spatial dissimilarity in diet. The study suggests that the two species are able to coexist within the same geographical area through niche differentiation across trophic and temporal ecological axes, with varying spatial use. The intra- and inter-specific differences between the two species may complicate elasmobranch management efforts for these co-occurring endemic catsharks, and as such, efforts should follow either an individual species approach, which is often not feasible, or an ecosystem-based approach, as opposed to considering the genus as a whole.Thesis (PhD) -- Faculty of Science, Ichthyology and Fisheries Science, 202

A comparison of soil liming requirement methodologies in temperate, Northern European pedo‐climates

ACKNOWLEDGEMENTS Funding for this research was provided through a PhD studentship by Scotland's Rural College (SRUC) and the University of Aberdeen.Peer reviewedPublisher PD

Understanding the emotional response of being a young carer of a combat veteran with PTSD: a narrative inquiry

Due to extended military commitments and deployments to Iraq and Afghanistan over the last 20 years, the ferocity of combat has led to some serving members of the military returning home with physical and mental health issues including Post Traumatic Stress Disorder (PTSD). Many of these individuals are parents and their PTSD diagnosis is likely to have a significant impact on their children. Much of the research which has been undertaken in relation to military families points to a lack of supportive structures post combat operations and highlights poor family integration and functioning leaving many children within the military community at risk of presenting with behavioural, emotional and mental health issues. Young carers are a group of children and young people who provide a vital role within their families and their communities by providing unpaid care to a family member over prolonged periods of time. It is not known how many children and young people within the military community undertake caring responsibilities and to date no studies have explored the emotional impact of being a young carer to a veteran parent with PTSD or investigated the impact that providing care has on child/parent relationships. This study sought to identify the lived experience of young carers of veterans with combat related PTSD by investigating their own perspectives as well as the perspectives of their mothers. Narrative inquiry was used to capture the narratives of the young carers in order to understand the emotional impact that caring had on them and how it impacted on their relationship with the parent with PTSD. The narratives of the young carers’ mothers were also captured. This enabled the researcher to produce stories of how young carers who were caring for a veteran parent with PTSD were able to renegotiate family life and family relationships and manage their emotions post diagnosis. The theoretical lens of this study is situated in Symbolic Interactionism (Bulmer, 1969), an ontological assumption based on the belief that reality is ‘socially constructed’, and an emic epistemological foundation built on subjective lived experience. The study investigated how the young carers orientated their thoughts, feelings and emotions based on their activities of daily living and their interactions with their families, friends, and their community, whilst providing care for a veteran parent with combat related PTSD. Interviews were used to capture and explore the participants’ narratives. Using Narrative Inquiry as a qualitative method and subsequently inquiring into the meaning of the narratives furthered understanding of family relationships and roles undertaken within the family environment. It also furthered understanding of what it is like to care for a parent with PTSD by capturing the emotional costs for the child by considering their lives pre-PTSD presentation as well as post-PTSD diagnosis. Qualitative interviews with 4 young carers from 3 families and their mothers were used to address the aims of the study. The young carers, two girls and two boys who were aged between 12 and 16 years of age were all providing care to a veteran father or stepfather, but they did not necessarily identify as ‘young carers’. The findings of this study suggest there may be common experiences amongst young carers who care for a veteran with PTSD. All of the participants’ emotional health was adversely affected by being a young carer to a father/stepfather with a PTSD diagnosis as was their social connectedness and the functionality of their family. However, whilst the young carers within this study all shared similar experiences in terms of providing care for a father with a diagnosis of PTSD due to military combat exposure, each family, and each young carers’ experience was unique. The findings suggest there is a need for policy makers and service providers to devise a universal definition of ‘what’ a young carer is in order to aid identification of young carers in military families. There is also a need to provide specific service provision for young carers from the military community so we can better meet their unique needs. This should be co- constructed with young carers themselves and their views should inform future policy developments. The findings suggest those who provide support to young carers and their families may also benefit from military awareness training

Low enthalpy heat recovery potential from coal mine discharges in the South Wales Coalfield

Fossil fuels generate the majority of space heating and hot water demand in the UK, contributing to greenhouse gas emissions and energy security issues. Concerns about the long term availability of traditional fossil fuels are recognised by the UK government and sustainable, low carbon supplies are being actively investigated. One such option in the renewable energy mix is the use of low enthalpy heat, using open loop ground source technology to recover heat from abandoned flooded coal mines. To assess this potential in the South Wales Coalfield we measured annual temperatures and chemistry at sixteen mine water sites. Mean monthly temperatures ranged from 10.3 to 18.6 °C with an overall mean of 13.3 °C, proving their suitability for low enthalpy heat recovery. Collated data shows the geothermal gradient can vary within the South Wales Coalfield. Exothermic chemical reactions within abandoned mine workings can also contribute to the overall temperature of mine waters. Using discharge and temperature data we estimate that 42 MW of potential heating energy could be generated from currently monitored mine water discharges, however historic dewatering data from operational mines suggests that 72 MW could be generated, enough to heat about 6500 homes. The true potential, if new pumping wells were drilled to exploit flooded workings is likely to be much greater. The use of low enthalpy mine water for space heating and hot water indicate a total emission reduction of around 59% and 76% compare to main gas and electricity heating respectively

Measurements of total alkalinity and inorganic dissolved carbon in the Atlantic Ocean and adjacent Southern Ocean between 2008 and 2010

Water column dissolved inorganic carbon and total alkalinity were measured during five hydrographic sections in the Atlantic Ocean and Drake Passage. The work was funded through the Strategic Funding Initiative of the UK's Oceans2025 programme, which ran from 2007 to 2012. The aims of this programme were to establish the regional budgets of natural and anthropogenic carbon in the North Atlantic, the South Atlantic, and the Atlantic sector of the Southern Ocean, as well as the rates of change of these budgets. This paper describes in detail the dissolved inorganic carbon and total alkalinity data collected along east–west sections at 47° N to 60° N, 24.5° N, and 24° S in the Atlantic and across two Drake Passage sections. Other hydrographic and biogeochemical parameters were measured during these sections, and relevant standard operating procedures are mentioned here. Over 95% of dissolved inorganic carbon and total alkalinity samples taken during the 24.5° N, 24° S, and the Drake Passage sections were analysed onboard and subjected to a first-level quality control addressing technical and analytical issues. Samples taken along 47° N to 60° N were analysed and subjected to quality control back in the laboratory. Complete post-cruise second-level quality control was performed using cross-over analysis with historical data in the vicinity of measurements, and data were submitted to the CLIVAR and Carbon Hydrographic Data Office (CCHDO), the Carbon Dioxide Information Analysis Center (CDIAC) and and will be included in the Global Ocean Data Analyses Project, version 2 (GLODAP 2), the upcoming update of Key et al. (2004)

Dry-coupled airborne ultrasonic inspection using coded excitation

Unmanned Aerial Vehicles (UAVs) offer significant potential benefits to the inspection of large-scale facilities due to their ability to access areas where manual inspection is not practical. Ultrasonic inspections typically utilise acoustic couplant, placed between the specimen and transducer surfaces, to eliminate any air gap and enable acoustic energy propagation. Conventional ultrasonic inspection UAVs contain a mechanical system to deliver a small quantity of liquid couplant between the transducer and inspection surface. Such mechanisms increase the system payload, resulting in the reduction of UAV flight endurance and inspection efficiency. Any couplant remaining on the surface may also increase the risk of corrosion. Instead of a liquid couplant layer, dry-coupled ultrasonic transducers utilise a thin layer of rubberised material. However, the acoustic characteristics of the conformable materials typically result in dry-coupled transducers with a lower Signal-to-Noise Ratio (SNR) than liquid-coupled sensors. Coded excitation, a pulse compression technology, improves SNR without sacrificing the measurement acquisition rate, as is the case with signal averaging. This paper explores the potential for application of coded excitation to maintain the SNR aboard a UAV deploying a dry-coupled transducer

Parity and breast cancer risk among BRCA1 and BRCA2 mutation carriers.

INTRODUCTION: Increasing parity and age at first full-term pregnancy are established risk factors for breast cancer in the general population. However, their effects among BRCA1 and BRCA2 mutation carriers is still under debate. We used retrospective data on BRCA1 and BRCA2 mutation carriers from the UK to assess the effects of parity-related variables on breast cancer risk. METHODS: The data set included 457 mutation carriers who developed breast cancer (cases) and 332 healthy mutation carriers (controls), ascertained through families seen in genetic clinics. Hazard ratios were estimated by using a weighted cohort approach. RESULTS: Parous BRCA1 and BRCA2 mutation carriers were at a significantly lower risk of developing breast cancer (hazard ratio 0.54, 95% confidence interval 0.37 to 0.81; p = 0.002). The protective effect was observed only among carriers who were older than 40 years. Increasing age at first live birth was associated with an increased breast cancer risk among BRCA2 mutation carriers (p trend = 0.002) but not BRCA1 carriers. However, the analysis by age at first live birth was based on small numbers. CONCLUSION: The results suggest that the relative risks of breast cancer associated with parity among BRCA1 and BRCA2 mutation carriers may be similar to those in the general population and that reproductive history may be used to improve risk prediction in carriers.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are