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Individually tracked Lesser Black-backed Gulls Larus fuscus rarely visited offshore areas in this study but showed high variation across multiple time scales in overall area use. To quantify the variation in space use by Lesser Black-backed Gulls, a species of conservation concern, from short- and long-term data on tracked individuals, and to assess the time spent offshore and interacting with offshore wind farms (OWFs) before and after their construction. GPS tracking data were collected between 2016 and 2019 from 36 Lesser Black-backed Gulls breeding in a declining colony in the UK with several operational OWFs nearby. Variations in home ranges, foraging trip metrics and the proportion of time spent offshore or within OWFs were analysed at three temporal scales: (i) over a daily cycle, (ii) across the breeding season and (iii) between years. Individuals predominantly used terrestrial areas. Less than 1.25% of the overall breeding season time budgets were spent offshore across years, and offshore use and time within OWFs did not vary significantly between years. However, home range sizes and foraging trip metrics did vary significantly across all time scales and individual variation was significant. Our results suggested that there was little change in the relative use of offshore areas over time and thus in the macro-scale response of Lesser Black-backed Gulls to the OWFs, one of which was under construction during the period of study. Colony productivity and changes in the terrestrial environment were likely to be more important for influencing foraging movements at this colony. [ABSTRACT FROM AUTHOR]

Emissions levels from current gasoline spark-ignited engines are low, and emissions changes associated with the blending of ethanol into gasoline are small and difficult to quantify. Addition of ethanol, with a high blending octane number, allows a reduction in aromatics in market gasoline. Blending behavior of ethanol is nonlinear, altering the distillation curve, including the 50% temperature point, T50. Increase in gasoline direct injection (GDI) engine technology in the fleet challenges ability of older models based on port fuel injection (PFI) results to predict the overall air quality impact of ethanol blending. Five different models derived from data collected through U.S. Environmental Protection Agency Energy Policy Act (EPAct) programs were used to predict LA92 Phase 1 particulate matter (PM) emissions for summer regular (SR) E0 (gasoline with 0% ethanol by volume), E10 (gasoline with 10% ethanol) and E15 (gasoline with 15% ethanol). Substantial reductions of PM for E10 and E15 relative to E0 were predicted when aromatics were displaced by ethanol to maintain octane rating. SR E0 and E10 were also matched to linear combinations of EPAct fuels and results showed a 35% PM reduction for SR E10 relative to SR E0. For GDI vehicles the Coordinating Research Council (CRC) E-94-3 study found that E10 had 23% or 29% PM increase. However, CRC E-129 found an E10 PM reduction of 10% when one E0 fuel and its splash blended (SB) E10 were compared. Both CRC project E-129 SB data and fuel triplets selected from the EPAct study showed variation for E15 emissions, although E-129 suggests that E15 in GDI offers about a 25% reduction of PM with respect to E0. Overall, data suggest that ethanol blending offers a modest to a substantial reduction of cold-start PM mass if aromatic levels of the finished products are reduced in response to ethanol addition. Implications: Studies of exhaust emissions effects of ethanol blending with gasoline vary in conclusions. Blending properties are nonlinear. Modeling of real-world emissions effects must consider all fuel composition adjustments and property changes associated with ethanol addition. Aromatics are reduced in E10 or E15, compared with E0, and distillation changes. PFI-derived models show reductions in cold-start PM for expected average E10 versus E0 pump fuel, due to reduced aromatic content. Relative emissions effects from older technology (PFI) engines do not predict newer engine (GDI) results reliably, but recent GDI data show reduced cold-start PM when ethanol displaces aromatics. [ABSTRACT FROM AUTHOR]

For distributed electrical power generation, linear engine-alternator systems have the potential to operate at high efficiency. They avoid the frictional losses present in rotating generators and enable the use of efficient combustion modes. However, their design and control optimization are matters of novelty. In this research, a single cylinder, two-stroke, free piston engine model has been built and simulated. The model describes the coupling between the piston motion dynamics and the chemical kinetics of the in-cylinder charge mixture undergoing homogeneous charge compression ignition (HCCI) combustion. The chemical kinetics reactions have been employed to find the net heat release rate and the start of combustion. Piston motion depends on the cylinder pressure as well as the dynamics of the mass-spring-damper system translator. For advanced investigations, the model results are represented by a multi-cycle simulation where 100 engine cycles were simulated with an average frequency of 125 Hz. At near-steady state conditions, the electrical generator converts 47% of the total fuel energy to electrical work at stoichiometric combustion conditions. It is shown that HCCI ignition timing strongly affects the performance of the engine. Combustion timing just before piston top dead center position encourages better engine stability and performance for the given model. The stability of the engine strongly depends on the rate of work done on the translator by the generator, putting the generator thrust force at the core of the engine control scheme. Cycle to cycle stability, with HCCI combustion occurring for each compression stroke, is achieved with the use of a modified proportional-derivative controller which alters the generator thrust force based on the cyclic change in the piston bottom dead center position. The research goal is to develop an optimized design with stable controls that yields a high efficiency conversion of chemical to electrical energy. [ABSTRACT FROM AUTHOR]

Today’s heavy-duty natural gas–fueled fleet is estimated to represent less than 2% of the total fleet. However, over the next couple of decades, predictions are that the percentage could grow to represent as much as 50%. Although fueling switching to natural gas could provide a climate benefit relative to diesel fuel, the potential for emissions of methane (a potent greenhouse gas) from natural gas–fueled vehicles has been identified as a concern. Since today’s heavy-duty natural gas–fueled fleet penetration is low, today’s total fleet-wide emissions will be also be low regardless of per vehicle emissions. However, predicted growth could result in a significant quantity of methane emissions. To evaluate this potential and identify effective options for minimizing emissions, future growth scenarios of heavy-duty natural gas–fueled vehicles, and compressed natural gas and liquefied natural gas fueling stations that serve them, have been developed for 2035, when the populations could be significant. The scenarios rely on the most recent measurement campaign of the latest manufactured technology, equipment, and vehicles reported in a companion paper as well as projections of technology and practice advances. These “pump-to-wheels”(PTW) projections do not include methane emissions outside of the bounds of the vehicles and fuel stations themselves and should not be confused with a complete wells-to-wheels analysis. Stasis, high, medium, and low scenario PTW emissions projections for 2035 were 1.32%, 0.67%, 0.33%, and 0.15% of the fuel used. The scenarios highlight that a large emissions reductions could be realized with closed crankcase operation, improved best practices, and implementation of vent mitigation technologies. Recognition of the potential pathways for emissions reductions could further enhance the heavy-duty transportation sectors ability to reduce carbon emissions. Implications: Newly collected pump-to-wheels methane emissions data for current natural gas technologies were combined with future market growth scenarios, estimated technology advancements, and best practices to examine the climate benefit of future fuel switching. The analysis indicates the necessary targets of efficiency, methane emissions, market penetration, and best practices necessary to enable a pathway for natural gas to reduce the carbon intensity of the heavy-duty transportation sector. [ABSTRACT FROM PUBLISHER]

Tracking devices are useful in studying the movement and behaviour of birds throughout the year. However, the effects of device attachment must be monitored for bird welfare and the scientific veracity of information gathered. We report on a trial of three different harness types (leg-loop, body and wing) for attaching GPS devices to Lesser Black-backed Gulls Larus fuscus and of a leg-loop harness on Great Skuas Stercorarius skua. This trial evaluated the functionality of the device whilst deployed, harness retention and the effects of each harness on the birds. The leg-loop harness prevented the devices from charging, due to feathers overlapping their solar panels, and individuals of both species shed this attachment during the first breeding season. For Lesser Black-backed Gull, devices functioned properly when attached using body and wing harnesses; foraging behaviour and territory attendance of birds were similar to the findings of other studies. Despite small sample sizes, annual adult survival rates for Lesser Black-backed Gull were similar to published estimates, suggesting harnesses had no deleterious effects. The wing harness has a smaller amount of skin contact than the body harness, and a non-constricting fit that better accommodates changes in body size. The wing harness was therefore considered the most appropriate for long-term studies. [ABSTRACT FROM AUTHOR]

Recent decades have seen a series of high-profile public health crises involving viruses, bacteria and other biological agents, together with escalating concern over impacts of biological invasion on crops and ecosystems. In the context of intensifying globalization, such hazards are being viewed as serious ‘security’ threats. For critical social theorists, this growing concern with biosecurity at the global scale has worrying implications, in that it promotes a state of fear over ‘life itself’ which is being used to justify heightened surveillance and increasingly intrusive intervention. However, there are alternative perspectives on living with adventitious and unpredictable biological life. For over a century and a half, ‘settler societies' such as Aotearoa New Zealand and Australia have been grappling with the environmental and economic impacts of non-native organisms running wild. Examining events surrounding an incursion of tussock moths in Auckland, it is argued that biosecurity policy can also be viewed as a flexible and evolving response to uncertainties associated with translocated biological life. Furthermore, the ‘peripheral’ tradition of sustained inquiry around the issue of which organisms belong in which places leads us back to questions about the characteristics of insects themselves and about the dynamics of the environments with which they interact. In this way, critical thinking around biosecurity is opened to a depth of engagement with evolutionary and geological processes that offer new dimensions to thinking about the ‘biopolitics' and ‘geopolitics' of encountering life out of bounds. [ABSTRACT FROM AUTHOR]

The oxides of nitrogen (NOx) emissions of diesel engines consist of nitric oxide (NO) and nitrogen dioxide (NO2). Although emitted at small amounts, NO2 has higher toxicity and causes more health and environmental issues than NO. This research investigates the impact of the addition of hydrogen (H2), natural gas (NG), and engine load on NO2 emissions from a heavy-duty diesel engine converted to operate using dual fuel combustion mode. The substitution of a small amount of H2 or NG for the diesel fuel substantially increased NO2 emissions, but had a very mild impact on the combustion process. In comparison, the substitution of a large amount of H2 and NG for the diesel fuel dramatically altered the combustion process and produced more NO2 than the diesel-only operation, but produced less NO2 than the addition of a small amount of H2 and NG. A preliminary analysis revealed a firm correlation between NO2 emissions and the emissions of the unburned H2 or CH4, and their relative emissions. The importance of the unburned fumigation fuels in enhancing NO2 formation in dual fuel engines was also supported by the data reported in the literature. The portion of supplemental fuels entrained into the diesel spray plume and simultaneously burned with the diesel fuel may not contribute to the increased NO2 emissions from dual fuel engines. [ABSTRACT FROM PUBLISHER]

The article focuses on the response of people in Florida following the hurricane Katrina in 2005, suggesting generosity to the victims of the calamity. It offers information on the moves of the people helping the victims from the calamity. The author notes that due to the catastrophic events from nature, several issues were created including the social ordering or communal formation that responds to the imperatives of the earth.

Attempts to reconnect ecological questions to an extended sense of care and obligation in time of environmental crisis. Discourses in ecological citizenship; Restraint and responsibility over the promotion of self-interest; Environmental movement against the commercialization of nature.

Nanotechnology or molecular engineering is a hypothetical regime of technics based on the precision manipulation of atoms to form workable devices or useful structures. Its proponents suggest that ‘nano’ could extend the manipu‐lability of digital information‐processing to the material realm, raising the possibility that the ‘information revolution’ is only part of a far more encompassing set of techno‐cultural transformations. Historical evidence of translation between systems of signification and modes of material transformation suggests that this prospect deserves serious consideration. Although the imperative of nanotech tends to be presented as one of extending control and design, it is argued that the self‐replicating and possibly self‐directing nature of ‘intelligent’ nanomachines raises the possibility of runaway dispersals. In this sense, nanotech may turn out to have more in common with autonomous digital entities — such as intelligent software agents, artificial life organisms or computer viruses — than with conventional data processing. It is suggested that the rise of autonomous, self‐argumenting or ‘autopoietic’ machine systems — both digital and materialized — has radical implications for received notions of agency, perception and subjectivity in general. It also raises important questions about the desirability of democratizing access to the forthcoming technologies. The possibility of unregulated ‘molecular hacking’ has frightening implications, but so too does the prospect of the monopolization of nanotech developments by powerful social forces. [ABSTRACT FROM AUTHOR]

Results from a study directed towards identifying and measuring the mutagenicity of diesel exhaust particulate matter involved in mining exposures, especially those which may synergistically affect genotoxic hazard, are presented in this paper. Particulate matter emissions from a diesel engine, representative of the ones found in underground mines, were sampled and assayed to determine the genotoxic potential as a function of engine operating conditions. Diesel exhaust was diluted in a multi‐tube mini‐dilution tunnel and the particulate matter was collected on 70 mm fluorocarbon coated glass fiber filters as well as on 8” × 10” hi‐volume filters. A six node steady state duty cycle was used to relate engine operating conditions to the mutagenicity potential. Protocols developed for using a primary component of pulmonary surfactant as a medium for collecting and applying respirable particulate material to cells for mutagenicity testing offer a true representation of in‐vivo delivery of such respired aerosols to pulmonary cells and the genetic material within. The surfactant dispersion technique is discussed in this paper. Methods have been developed to sample and assay the diesel soot and diesel soot/mineral dust complexes which would not compromise the surface and physical properties of the particulate material. [ABSTRACT FROM PUBLISHER]