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Dataset "Impact of Carbon Sources in Airport De-icing Compounds on the Growth of Sphaerotilus natans"
No full textAirport de-icer contaminated surface runoff discharges have been implicated in the growth of undesirable river biofilms (URBs, formerly 'sewage fungus'), in this research we sought to establish a definitive link between de-icer contaminated discharges and the growth of the characteristic URB taxon, S. natans.
The dataset uploaded here is the raw optical density data from the high-throughput optical density instrument (BioScreen C MBR) used to monitor microbial growth.Natural Environment Research Council (NERC)NE/L002493/1Heathrow Airport Lt
Dataset for "Characterisation and anaerobic digestion of fat, oil and grease (FOG) waste from wastewater treatment plants"
No full textData set for Figure 3 and Figure
Boundary work in CVC: how boundary work enables the strategic use of CVC to create and unlock value
No full textIn this article, we build on and contribute to the literature on Corporate Venture Capital (CVC) through the lens of Boundary Work Theory. Analyzing interview data from several successful CVCs, we uncover boundary works (micro-strategies) taking place at and through organizational boundaries that enable collaboration amongst CVC stakeholders and balance competitive and collaborative forces within and across the organizational boundaries. CVCs are more complex than traditional institutional venture capitals (VCs) as they seek to maximize both strategic and financial returns. While extant research has shown that the strategic use of CVC creates value for the parent firm, none have explored how successful CVCs do this at and through the boundaries amongst different parties involved. We identify two overarching mechanisms, one at the boundaries that enable collaboration and the other through the boundaries that simultaneously bring certain CVC activities together whilst keeping others apart to enable collective action. Our findings portray a process model comprised of eleven micro-strategies that successful CVCs use to create and unlock value.84th Annual Meeting of the Academy of Management (AOM 2024
The impacts of airport de-icers on water quality and the growth of undesirable biofilms in rivers
Get PDFHassard, Francis - Associate Supervisor
Medina Vaya, Angel - Associate SupervisorUndesirable river biofilms (URBs, formerly “sewage fungus”) are polymicrobial
biofilms that grow in rivers as a response to organic pollution. Despite a continued
widespread occurrence, limited research has been conducted in recent decades.
Therefore, to reignite research into URBs, this thesis aims to investigate how the
delivery of airport de-icer contaminated runoff to receiving waters impacts the
growth and composition of URBs. The research conducted can be categorised
into four themes: (i) a re-evaluation of “sewage fungus”; (ii) a field study to
characterize the composition and drivers of URBs; (iii) microcosm growth
experiments to determine how different airport de-icers contribute to URB growth;
and (iv) pilot-scale mobilisation experiments to evaluate the mobilisation of airport
de-icers in surface runoff.
A bimonthly field study conducted over two winters revealed shifts in the bacterial
composition of riverbed biofilms with suspected de-icer discharge. The
community became dominated by the genera Rhodoferax (19.5 – 56.7% relative
abundance) and Sphaerotilus (9.5 – 25.4%) prior to and during a visible URB
incident. When aggregated at the family taxonomic level, Comamonadaceae
(55.7 – 81.4%) emerged as the key indicator taxon of the significant shift in
periphyton and has been proposed as a possible organic pollution biosentinel.
The URB had a long-term influence on the periphyton, highlighting the importance
of preventing their occurrence.
Microcosm experiments of URB taxa growth using common freeze-point
depressants as the sole carbon source confirmed de-icers can facilitate URB
growth. Sphaerotilus natans growth was stimulated by all de-icers, except
formate salts, in suspended culture (assessed by turbidimetric microcosms) and
total growth was heavily dependent on carbon concentration. There were some
significant differences in the growth kinetics between the active ingredients in de-
icers (e.g., maximum growth rate). However, there were only negligible
differences between pure active ingredients and their commercial products
demonstrating that the additives used in commercial de-icers have negligible
influence on microbial growth, despite their potential toxicity to aquatic fauna.
Growth experiments with mixed cultures using S. natans and Zoogloea
oleivorans were also tested to explore the interactions between URB taxa,
including the novel application of timelapse microscopy in URB growth studies
and provide a basis for further research.
Mobilisation of commercial airport de-icers by rainfall was tested after exposure
to various meteorological conditions (sun, wind, temperature) to explore the
transport pathways of de-icers in runoff. Runoff was significantly affected by
weather between de-icer application and a rainfall event. Sunlight and wind
caused less de-icer mobilisation than decreases in temperature, attributed to
drying effects. This research has considerable implications to inform surface
water winter management plans by airport operators.
This research highlights the continued prominence of URBs in rivers, even in
countries with advanced wastewater treatment, and has added substantial
contributions to knowledge about their composition and growth as a consequence
of airport de-icing activities. Through a process-based understanding of de-icer
transport and impact, airports can develop more effective and resilient solutions
to minimise the ecological impacts in receiving water courses.PhD in Water, including Desig
Is there a need for robots with moral agency? A case study in social robotics
Get PDFThere has been significant recent interest in the risks associated with Artificial Intelligence (AI), so much so that a Global AI Summit was recently hosted at Bletchley Park in the United Kingdom. One supposed risk associated with Artificial Intelligence is the threats that might be associated with an Artificial General Intelligence (AGI) carrying out acts detrimental to humanity. In the past, some researchers have attempted to bestow machines with morals to mitigate against these types of threat, however, in recent times the approach has been largely dismissed, with claims that giving machines moral agency poses more of a threat in of itself, than preventing it. One critique of the calls of the risk associated with AGI is that it is unrealistic, and that there is no grounding for any threat to humanity. The aim of this paper is to present a case study in social robotics to illustrate two points: 1) what real-life risks associated with AI might be, and 2) to reinstate the discussion surrounding whether there is a requirement for robots with moral agency.2024 IEEE International Conference on Industrial Technology (ICIT
On-orbit servicing strategies for large constellations via hybrid dynamic programming
Get PDFThe increasing number of mega-constellations inLEOis not only increasing the number of satellites in orbit but potentially might trigger an increment in the amount of space debris. On-orbit servicing is seen as a viable solution to minimize the number of launches needed to maintain these constellations and keep the debris levels low. This paper focuses on trajectory planning for On-Orbit Servicing (OOS) by presenting a novel methodology based on dynamic programming hybridized with deterministic tree search strategies. This is used to schedule the best path for spacecraft to visit satellites that need servicing (such as repair, refueling or repositioning). This methodology is then used to conduct Monte Carlo simulations to study how the main characteristics of the spacecraft affect the performance of the servicing operation. The presented study aims to find the optimal number of servicers needed, the ^V required to perform the operations, and the time of flight between satellites.2024 CEAS EuroGNC Conferenc
Characterisation and fragmentation of brass and copper pipe bombs when using different initiation locations
Get PDFThe fragmentation characteristics of pipe bombs made from copper and brass, filled with a single base propellant, and initiated with an electric match positioned either at the end or halfway along the pipe were studied. A rig was devised to negate any variation from the effectiveness of end caps. Fragments were captured in strawboard packs and recovered to enable imaging and Fragment Weight Distribution Mapping (FWDM) graphs. The position of the initiator had a measurable effect on the fragmentation of the copper pipe, with the middle-initiated pipes having a higher relative power. In contrast, no such clear link was evident for the brass pipes. This likely indicates that the initiator location has less of an effect in stronger materials which are able to confine the propellant prior to rupturing
The scarring effects of initial labor market conditions on South Korean nurses
Get PDFUsing a longitudinal dataset spanning the period 2000-2020, and an identification strategy based on instrumental variables, we examine the existence of scarring in the context of the Korean nursing profession. We find that the prevailing unemployment rate at time of graduation has negative effects on nurses’ wages that remain highly significant up to 6 years after joining the labor market, while working hours are positively scarred for up to 10 years. We also estimate a series of happiness equations to understand nurses’ experiences after joining the labor market, and find that a higher unemployment rate at time of graduation is associated with feelings of worse financial conditions, less happy lives, and lower income satisfaction.Seoul Journal of Economic
‘The darker angels of our nature’: Early Bronze Age butchered human remains from Charterhouse Warren, Somerset, UK
Get PDFDirect physical evidence for violent interpersonal conflict is seen only sporadically in the archaeological record for prehistoric Britain. Human remains from Charterhouse Warren, south-west England, therefore present a unique opportunity for the study of mass violence in the Early Bronze Age. At least 37 men, women and children were killed and butchered, their disarticulated remains thrown into a 15m-deep natural shaft in what is, most plausibly, interpreted as a single event. The authors examine the physical remains and debate the societal tensions that could motivate a level and scale of violence that is unprecedented in British prehistory.This work was supported by a British Academy grant (SG163375). The radiocarbon dates were funded by NERC’s NEIF programme (NF/2018/1/3).Isotope analyses were partially funded by a British Academy Newton International Fellowship to T.F-C (NF17085).Antiquit
Disaster area coverage optimisation using reinforcement learning
Get PDFSearch and rescue applications using unmanned aerial vehicles (UAVs) also known as drones are becoming a research topic of interest to industry and academia due to its high impact in the ecosystem and people. Exploration of the disaster area is a crucial element in search and rescue to identify the zones that require immediate assistance or with high hazard probability. This paper aims to contribute in the coverage optimisation of a disaster area using drones. We focus on a flood disaster scenario as case of study. The proposed approach consists in two main parts: i) a Siamese-net is used to identify flooded buildings in satellite images, and ii) the points of interest are converted into a suitable maze environment that subsequently is used by any reinforcement learning (RL) architecture for area coverage optimisation. Here, the goal of the RL architecture is to ensure that the complete environment is covered by the drone by optimizing time and previously visited zones. Experiments are conducted to show the benefits and challenges of the current approach.Engineering and Physical Sciences Research Council (EPSRC)2024 International Conference on Unmanned Aircraft Systems (ICUAS