Eco-positioning of airlines: Perception versus actual performance

To date there has been little research in air transport into the eco-positioning of airlines, that is, their environmental image relative to other airlines and how actual environmental performance relates to this eco-positioning. This paper identifies the environmental perceptions that passengers hold of twelve airlines and relates these perceptions to airlines' actual environmental performance, using load factors, aircraft age and the atmosfair Airline index as proxies for environmental performance. Based on a survey of over 600 passengers at Liverpool John Lennon Airport, the research analyses air travellers' perception of airlines from an environmental perspective. The results show that while there are significant differences in people's environmental perception of airlines, the eco-positioning of the airlines is not correlated to their actual environmental performance. The results support previous research findings in other industries that in many cases actual performance is less important than communicating environmental messages to the public in creating a superior eco-positioning

The role of Green Marketing: Insights from three airline case studies

The purpose of this paper is to show how airlines incorporate green elements in their marketing mix and how these changes are communicated to the public. Based on an examination of airlines' websites and publications as well as a review of academic and industry literature, three airline case studies on Virgin Atlantic Airways, easyJet and Flybe are developed. A multiple case design is applied that provides an in-depth review of the airlines' environmental activities and enables differences between their green marketing activities to be identified. All three airlines have adapted their marketing mix to address the environmental impacts of air transport. While there are some commonalities between the airlines (e.g. market communications addressing green credentials), there are also some differences in how the airlines approach the issue. Services are often seen as low-impact industries when it comes to environmental impacts, yet there are certain service sectors that have recognisable environmental impacts. The airline sector has received considerable attention regarding their emissions and they have responded to negative coverage of their environmental impacts. The paper presents an original multiple case study of the green marketing of three airlines. It provides a comparison between three airlines and highlights commonalities as well as differences in green marketing of the three airlines

Can bus really be the new tram?

Bus Rapid Transit (BRT) appears to be less expensive to build and operate than tram systems but can it really approach the performance level of a tram system and what is the environmental performance of comparable systems? This paper reports systematic research on these issues, particularly relating to where an urban transit system seeks to attract discretionary car users. A model has been developed to compare the implementation, operational costs and environmental impacts of a comparable tram and high quality guided BRT system. This models a UK situation, but draws upon information from elsewhere in Europe and North America. The design of the BRT system delivers equivalent performance to trams in capacity and passenger experience. This ‘equivalence’ model shows that the capital costs of the high-spec BRT system are two-thirds those of tram. This is less of a cost saving than is often claimed, suggesting that, in practice, BRT is built to a lower specification that tram systems. Operational costs do not significantly differ. Using hybrid-engine BRT vehicles, CO2 emissions are similar, BRT has lower PM10 emissions, but NOx from BRT remains higher than for trams. Although the cost differences for equivalent systems are less than is often claimed, there are substantial benefits in the flexible development of BRT, with it less vulnerable to variations from forecast ridership numbers, and development can be split into fundable stages, growing the business case for incremental upgrading. High-spec BRT can to be the new tram, but the ‘value for money’ case for BRT should not be at the expense of quality and transport planning impact

Passenger perceptions of the green image associated with airlines

Environmental issues in air transport have grown in importance in recent years, and in response some airlines have been proactive to demonstrate their ‘green’ credentials. The aim of this paper is to identify air traveller perceptions of different airlines with regard to green image, and how passengers perceive different measures that airlines can introduce to reduce their environmental impact. The research is based on a large quantitative survey, of over 600 air travellers, conducted at Liverpool John Lennon Airport between April and July 2010. The data in this papers stems from a range of attitudinal statements on airlines, and measures that airlines could adopt to improve their environmental performance. When presented with a list of airlines, about half of respondents were able to differentiate between airlines based on environmental friendliness. The results show that low-cost airlines in general are not seen as more or less environmentally friendly than full service network airlines. Yet air travellers do indicate differences in the environmental image based on individual airlines. Furthermore, results vary depending on whether passengers had flown previously with a particular airline. Passengers also differentiate between measures that airlines can adopt to reduce the environmental impact of aviation. Using newer aircraft is seen as the most effective way to address the issue

In Vitro , Ex Vivo , and In Vivo Activities of Diamidines against Trypanosoma congolense and Trypanosoma vivax

ABSTRACT African animal trypanosomosis (AAT) is caused by the tsetse fly-transmitted protozoans Trypanosoma congolense and T. vivax and leads to huge agricultural losses throughout sub-Saharan Africa. Three drugs are available to treat nagana in cattle (diminazene diaceturate, homidium chloride, and isometamidium chloride). With increasing reports of drug-resistant populations, new molecules should be investigated as potential candidates to combat nagana. Dicationic compounds have been demonstrated to have excellent efficacy against different kinetoplastid parasites. This study therefore evaluated the activities of 37 diamidines, using in vitro and ex vivo drug sensitivity assays. The 50% inhibitory concentrations obtained ranged from 0.007 to 0.562 μg/ml for T. congolense and from 0.019 to 0.607 μg/ml for T. vivax . On the basis of these promising results, 33 of these diamidines were further examined using in vivo mouse models of infection. Minimal curative doses of 1.25 mg/kg of body weight for both T. congolense - and T. vivax -infected mice were seen when the diamidines were administered intraperitoneally (i.p.) over 4 consecutive days. From these observations, 15 of these 33 diamidines were then further tested in vivo , using a single bolus dose for administration. The total cure of mice infected with T. congolense and T. vivax was seen with single i.p. doses of 5 and 2.5 mg/kg, respectively. This study identified a selection of diamidines which could be considered lead compounds for the treatment of nagana

Environmental effects of aircraft operations and airspace charging regimes. Final report

Project aim and outline: There has been anecdotal evidence that differences in airspace charging regimes influence airlines’ preferred routes and flight plans through European airspace. Routing aircraft over longer distances in order to reduce direct operating costs has a range of fuel burn and greenhouse gas emission consequences that have yet to be adequately quantified. The aim of this project is to study the environmental costs of different airspace charging regimes in Europe to ascertain whether the level of route charges that are levied for performing a flight affects the route that is flown between specific origin/destination pairs. Through a strategic assessment of a sample of airline flight plans and discussion with stakeholders, the study investigates the drivers of these apparently inefficient flight plans, quantifies the proportion of European routes that are affected (and the additional distances that are travelled) and identifies the greenhouse gas emission (focussing on carbon dioxide) implications of the observed behaviours

Effect of Limb Lengthening on Internodal Length and Conduction Velocity of Peripheral Nerve

The influences of axon diameter, myelin thickness, and internodal length on the velocity of conduction of peripheral nerve action potentials are unclear. Previous studies have demonstrated a strong dependence of conduction velocity on internodal length. However, a theoretical analysis has suggested that this relationship may be lost above a nodal separation of ∼0.6 mm. Here we measured nerve conduction velocities in a rabbit model of limb lengthening that produced compensatory increases in peripheral nerve growth. Divided tibial bones in one hindlimb were gradually lengthened at 0.7 mm per day using an external frame attached to the bone. This was associated with a significant increase (33%) of internodal length (0.95–1.3 mm) in axons of the tibial nerve that varied in proportion to the mechanical strain in the nerve of the lengthened limb. Axonal diameter, myelin thickness, and g-ratios were not significantly altered by limb lengthening. Despite the substantial increase in internodal length, no significant change was detected in conduction velocity (∼43 m/s) measured either in vivo or in isolated tibial nerves. The results demonstrate that the internode remains plastic in the adult but that increases in internodal length of myelinated adult nerve axons do not result in either deficiency or proportionate increases in their conduction velocity and support the view that the internodal lengths of nerves reach a plateau beyond which their conduction velocities are no longer sensitive to increases in internodal length

Expression of the neuroprotective slow Wallerian degeneration (WldS) gene in non-neuronal tissues

<p>Abstract</p> <p>Background</p> <p>The slow Wallerian Degeneration (<it>Wld</it>^<it>S</it>) gene specifically protects axonal and synaptic compartments of neurons from a wide variety of degeneration-inducing stimuli, including; traumatic injury, Parkinson's disease, demyelinating neuropathies, some forms of motor neuron disease and global cerebral ischemia. The <it>Wld</it>^{<it>S </it>}gene encodes a novel Ube4b-Nmnat1 chimeric protein (Wld^Sprotein) that is responsible for conferring the neuroprotective phenotype. How the chimeric Wld^Sprotein confers neuroprotection remains controversial, but several studies have shown that expression in neurons <it>in vivo </it>and <it>in vitro </it>modifies key cellular pathways, including; NAD biosynthesis, ubiquitination, the mitochondrial proteome, cell cycle status and cell stress. Whether similar changes are induced in non-neuronal tissue and organs at a basal level <it>in vivo </it>remains to be determined. This may be of particular importance for the development and application of neuroprotective therapeutic strategies based around <it>Wld</it>^<it>S</it>-mediated pathways designed for use in human patients.</p> <p>Results</p> <p>We have undertaken a detailed analysis of non-neuronal <it>Wld</it>^{<it>S </it>}expression in <it>Wld</it>^{<it>S </it>}mice, alongside gravimetric and histological analyses, to examine the influence of <it>Wld</it>^{<it>S </it>}expression in non-neuronal tissues. We show that expression of <it>Wld</it>^{<it>S </it>}RNA and protein are not restricted to neuronal tissue, but that the relative RNA and protein expression levels rarely correlate in these non-neuronal tissues. We show that <it>Wld</it>^{<it>S </it>}mice have normal body weight and growth characteristics as well as gravimetrically and histologically normal organs, regardless of Wld^Sprotein levels. Finally, we demonstrate that previously reported <it>Wld</it>^<it>S</it>-induced changes in cell cycle and cell stress status are neuronal-specific, not recapitulated in non-neuronal tissues at a basal level.</p> <p>Conclusions</p> <p>We conclude that expression of Wld^Sprotein has no adverse effects on non-neuronal tissue at a basal level <it>in vivo</it>, supporting the possibility of its safe use in future therapeutic strategies targeting axonal and/or synaptic compartments in patients with neurodegenerative disease. Future experiments determining whether Wld^Sprotein can modify responses to injury in non-neuronal tissue are now required.</p

Targeting phosphoglycerate kinase 1 with terazosin improves motor neuron phenotypes in multiple models of amyotrophic lateral sclerosis

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder with heterogeneous aetiology and a complex genetic background. Effective therapies are therefore likely to act on convergent pathways such as dysregulated energy metabolism, linked to multiple neurodegenerative diseases including ALS. METHODS: Activity of the glycolysis enzyme phosphoglycerate kinase 1 (PGK1) was increased genetically or pharmacologically using terazosin in zebrafish, mouse and ESC-derived motor neuron models of ALS. Multiple disease phenotypes were assessed to determine the therapeutic potential of this approach, including axon growth and motor behaviour, survival and cell death following oxidative stress. FINDINGS: We have found that targeting a single bioenergetic protein, PGK1, modulates motor neuron vulnerability in vivo. In zebrafish models of ALS, overexpression of PGK1 rescued motor axon phenotypes and improved motor behaviour. Treatment with terazosin, an FDA-approved compound with a known non-canonical action of increasing PGK1 activity, also improved these phenotypes. Terazosin treatment extended survival, improved motor phenotypes and increased motor neuron number in Thy1-hTDP-43 mice. In ESC-derived motor neurons expressing TDP-43(M337V), terazosin protected against oxidative stress-induced cell death and increased basal glycolysis rates, while rescuing stress granule assembly. INTERPRETATION: Our data demonstrate that terazosin protects motor neurons via multiple pathways, including upregulating glycolysis and rescuing stress granule formation. Repurposing terazosin therefore has the potential to increase the limited therapeutic options across all forms of ALS, irrespective of disease cause. FUNDING: This work was supported by project grant funding from MND Scotland, the My Name’5 Doddie Foundation, Medical Research Council Doctoral Student Training Fellowship [Ref: BST0010Z] and Academy of Medical Sciences grant [SGL023\1100]

Molecular neuropathology of the synapse in sheep with CLN5 Batten disease

© 2015 Published by Wiley Periodicals, Inc. Aims: Synapses represent a major pathological target across a broad range of neurodegenerative conditions. Recent studies addressing molecular mechanisms regulating synaptic vulnerability and degeneration have relied heavily on invertebrate and mouse models. Whether similar molecular neuropathological changes underpin synaptic breakdown in large animal models and in human patients with neurodegenerative disease remains unclear. We therefore investigated whether molecular regulators of synaptic pathophysiology, previously identified in Drosophila and mouse models, are similarly present and modified in the brain of sheep with CLN5 Batten disease. Methods: Gross neuropathological analysis of CLN5 Batten disease sheep and controls was used alongside postmortem MRI imaging to identify affected brain regions. Synaptosome preparations were then generated and quantitative fluorescent Western blotting used to determine and compare levels of synaptic proteins. Results: The cortex was particularly affected by regional neurodegeneration and synaptic loss in CLN5 sheep, whilst the cerebellum was relatively spared. Quantitative assessment of the protein content of synaptosome preparations revealed significant changes in levels of seven out of eight synaptic neurodegeneration proteins investigated in the motor cortex, but not cerebellum, of CLN5 sheep (α-synuclein, CSP-α, neurofascin, ROCK2, calretinin, SIRT2, and UBR4). Conclusions: Synaptic pathology is a robust correlate of region-specific neurodegeneration in the brain of CLN5 sheep, driven by molecular pathways similar to those reported in Drosophila and rodent models. Thus, large animal models, such as sheep, represent ideal translational systems to develop and test therapeutics aimed at delaying or halting synaptic pathology for a range of human neurodegenerative conditions