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To understand the jumping mechanisms and strategies of adult caddis flies, leg morphology and movements were analysed in three species with mean masses of 3.9 to 38 mg. Two distinct jumping strategies were found. First (67% of 90 jumps), take-off was propelled solely by the middle and hind legs while the wings remained closed. Second (33% of jumps), the same leg movements were combined with wing movements before take-off. The hind legs were 70% and the middle legs were 50% longer than the front legs and represented 105% and 88%, respectively, of body length. Both hind and middle trochantera were depressed together, approximately 15 ms before take-off. The front legs apparently did not contribute to thrust in either strategy and were the first to be lifted fromthe ground. The hind legswere the next to lose contact, so that the middle legs alone provided the final thrust before take-off. Jumping performance did not differ significantly in the two jumping strategies or between species, in acceleration times (range of means for the three species 14.5-15.4 ms), take-off velocities (range 0.7-1 m s-1) and trajectory angles. A significant difference in jumps propelled only by the legswas the lower angle (9.3± 1.9 deg) of the body relative to the horizontal at take-off compared with jumps involvingwingmovements (35.3±2.5 deg).Calculations fromthe kinematics indicated that jumps were produced by direct muscle contractions and did not require power amplification or energy storage. [ABSTRACT FROM AUTHOR]

BACKGROUND: Neck pain is considered to be a major health problem in modem societies. Many previous studies found that certain occupations are related to this problem or are associated with the risk of developing it in future. Although the pain is caused by mechanical factors, it may progress to a serious problem and give rise to other abnormal symptoms such as vertigo, headache, or migraine. OBJECTIVE: To investigate the prevalence of neck pain among the cabin crew of Saudi Airlines. DESIGN OF STUDY: A cross-sectional study was carried out on the available Saudi Airlines cabin crews in King Fahad Airport during our visits, using questionnaires and measurements of several parameters. METHODS: Neck Pain Questionnaires were distributed to the cabin crews on Saudi Airlines and assessment sheets were completed by all participants of the study to evaluate the prevalence and distribution of neck pain. Physical therapy examination of neck motions in different directions and specific tests were performed by all the participants to identify any symptoms. Using these data the prevalence of neck pain among the cabin crews was calculated. Collected data were analyzed statistically using SPSS software calculating the mean, median, and score of the questionnaire. RESULTS: According to the scoring system of the study, 31 (30.09%) of 105 cabin crew staff of Saudi Airlines had neck pain. Our study confirmed a positive correlation between this occupation and neck pain, and in fact found that according to the results of logistic regression analysis, this occupation is the only significant factor that affects the positive compression test. CONCLUSION: The prevalence of neck pain among the cabin crews of Saudi Airlines was emphasized. The results show a high prevalence of neck pain in the participants of the study, with most cases appearing to run a chronic - episodic course. Further research is needed to help us understand more about the long-term course of neck pain and its broader outcomes and impacts. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Helicopter flying is a complex psychomotor task requiring continuous control inputs to maintain stable flight and conduct maneuvers. Flight safety is impaired when this psychomotor performance is compromised. A comprehensive understanding of the psychomotor performance of helicopter pilots, under various operational and physiological conditions, remains to be developed. The purpose of this study was to develop a flight simulator-based technique for capturing psychomotor performance data of helicopter pilots. METHODS: Three helicopter pilots conducted six low-level flight sequences in a helicopter simulator. Accelerometers applied to each flight control recorded the frequency and magnitude of movements. RESULTS: The mean (± SEM) number of control inputs per flight was 2450 (± 136). The mean (± SEM) number of control inputs per second was 1.96 (± 0.15).The mean (± SEM) force applied was 0.44 G (± 0.05 G). No significant differences were found between pilots in terms of flight completion times or number of movements per second. The number of control inputs made by the hands was significantly greater than the number of foot movements. The left hand control input forces were significantly greater than all other input forces. DISCUSSION: This study shows that the use of accelerometers in flight simulators is an effective technique for capturing accurate, reliable data on the psychomotor performance of helicopter pilots. This technique can be applied in future studies to a wider range of operational and physiological conditions and mission types in order to develop a greater awareness and understanding of the psychomotor performance demands on helicopter pilots. [ABSTRACT FROM AUTHOR]

To test whether jumping launches moths into the air, take-off by 58 species, ranging in mass from 0.1 to 220 mg, was captured in videos at 1000 frames s-1. Three strategies for jumping were identified. First, rapid movements of both middle and hind legs provided propulsion while the wings remained closed. Second, middle and hind legs again provided propulsion but the wings now opened and flapped after take-off. Third, wing and leg movements both began before take-off and led to an earlier transition to powered flight. The middle and hind legs were of similar lengths and were between 10 and 130% longer than the front legs. The rapid depression of the trochantera and extension of the middle tibiae began some 3 ms before similar movements of the hind legs, but their tarsi lost contact with the ground before take-off. Acceleration times ranged from 10 ms in the lightest moths to 25 ms in the heaviest ones. Peak take-off velocities varied from 0.6 to 0.9 m s-1 in all moths, with the fastest jump achieving a velocity of 1.2 m s-1. The energy required to generate the fastest jumps was 1.1 pJ in lighter moths but rose to 62.1 µJ in heavier ones. Mean accelerations ranged from 26 to 90 m s-2 and a maximum force of 9 g was experienced. The highest power output was within the capability of normal muscle so that jumps were powered by direct contractions of muscles without catapult mechanisms or energy storage. [ABSTRACT FROM AUTHOR]

Resource polymorphism refers to individuals from the same population foraging in alternative habitats or on alternative food. Food specialization can be associated with adaptations such as colour polymorphism, with pale and dark colours conferring differential camouflage in different habitats. Pale and dark-reddish pheomelanic Barn Owls ( Tyto alba) forage on different prey species in closed and open habitats, respectively. We show here that darker-reddish owls have heavier stomach content when found dead, and their 5th secondary wing feather is more deeply anchored inside the integument. These correlations suggest that their feathers bend less when flying, and that darker-reddish Barn Owls are able sustain more intense flying than their paler conspecifics. [ABSTRACT FROM AUTHOR]

Lacewings launch themselves into the air by simultaneous propulsive movements of the middle and hind legs as revealed in video images captured at a rate of 1000 s-1. These movements were powered largely by thoracic trochanteral depressor muscles but did not start from a particular preset position of these legs. Ridges on the lateral sides of the meso- and metathorax fluoresced bright blue when illuminated with ultraviolet light, suggesting the presence of the elastic protein resilin. The middle and hind legs were longer than the front legs but their femora and tibiae were narrow tubes of similar diameter. Jumps were of two types. First, those in which the body was oriented almost parallel to the ground (-7±8 deg in green lacewings, 13.7±7 deg in brown lacewings) at take-off and remained stable once animals were airborne. The wings did not move until 5 ms after take-off when flapping flight ensued. Second, were jumps in which the head pointed downwards at take-off (green lacewings, -37±3 deg; brown lacewings, -35±4 deg) and the body rotated in the pitch plane once airborne without the wings opening. The larger green lacewings (mass 9 mg, body length 10.3 mm) took 15 ms and the smaller brown lacewings (3.6 mg and 5.3 mm) 9 ms to accelerate the body to mean take-off velocities of 0.6 and 0.5 m s-1. During their fastest jumps green and brown lacewings experienced accelerations of 5.5 or 6.3g, respectively. They required an energy expenditure of 5.6 or 0.7 µJ, a power output of 0.3 or 0.1 mW and exerted a force of 0.6 or 0.2 mN. The required power was well within the maximum active contractile limit of normal muscle, so that jumping could be produced by direct muscle contractions without a power amplification mechanism or an energy store. [ABSTRACT FROM AUTHOR]

The aim of this paper is to study: (1) the prevalence of flight anxiety among Norwegian airline passengers; (2) situations that may be of concern during flights and situations not related to flying; (3) whether passengers feel more afraid after the terror act of September 11, 2001; and (4) whether passengers were more afraid in 2002 than in 1986.A questionnaire was distributed during domestic flights in Norway in 1986 and 2002. To asses flight anxiety, a six point scale was used, from 0 = not afraid at all, to 5 = always very afraid, and sometimes avoid flying because of that. A 10-cm visual analogue scale ( VAS) was used to measure the degree of anxiety. There were 50.8% who were not afraid at all. There were 12 women (5.2%) and one man (0.4%) with flight phobia. However, 22 (4.5%) had cancelled flights because of anxiety during the last two years. Situations that caused most concern during flights were turbulence and fear of terrorism and highjacking. After September 11, 48% were not more afraid, 38% a little more, 10% moderately, 3% rather much and 2% very much. The passengers, however, were not more afraid of flying in 2002 than in 1986. About 3% of Norwegian airline passengers have a flight phobia. Women are significantly more concerned than men. The impact of the terror act September 11, 2001 was rather moderate. The level of flight anxiety among Norwegian airline passengers was not significantly different in 2002 and 1986. [ABSTRACT FROM AUTHOR]

Abstract: Air travel and total joint arthroplasty (TJA) are both risk factors for venous thromboembolism (VTE). Patients are counseled against flying after surgery, however the basis for this recommendation has not been investigated and may be unfounded. A retrospective cohort of 1465 consecutive TJA patients was divided into a study population of 220 patients (15.0%) who flew home at a mean of 2.9days after surgery (range, 1–10days) and a control population of 1245 patients (85.0%) who did not fly. We found no differences in the rate of deep vein thrombosis, pulmonary embolism, or overall VTE between the groups, and incidence of all events was low in both groups and comparable with published data. Allowing air travel after TJA appears to be a safe practice. [Copyright &y& Elsevier]

We describe and characterize a method for estimating the pressure field corresponding to velocity field measurements such as those obtained by using particle image velocimetry. The pressure gradient is estimated from a time series of velocity fields for unsteady calculations or from a single velocity field for quasi-steady calculations. The corresponding pressure field is determined based on median polling of several integration paths through the pressure gradient field in order to reduce the effect of measurement errors that accumulate along individual integration paths. Integration paths are restricted to the nodes of the measured velocity field, thereby eliminating the need for measurement interpolation during this step and significantly reducing the computational cost of the algorithm relative to previous approaches. The method is validated by using numerically simulated flow past a stationary, two-dimensional bluff body and a computational model of a three-dimensional, self- propelled anguilliform swimmer to study the effects of spatial and temporal resolution, domain size, signal-to-noise ratio and out-of- plane effects. Particle image velocimetry measurements of a freely swimming jellyfish medusa and a freely swimming lamprey are analyzed using the method to demonstrate the efficacy of the approach when applied to empirical data. [ABSTRACT FROM AUTHOR]

Foraging behaviour is one of the distinctive behaviours of honey bees, Apis mellifera. This behaviour is the link between the honey bee colony and the ambient environment. Therefore, various in-colony and out-colony factors have an impact on this behaviour, and many studies have been employed to investigate these factors. Foraging behaviour is not advantageous only for the colony and for plant pollination but also has other benefits. In contrast, some disadvantages have also been discovered to be linked with foraging activity. Practically speaking, the control over this behaviour is very important to maximize colony products as well as to increase other agricultural benefits. This paper presents a review on foraging activity including; the regulation of foraging tasks, factors impacting this behaviour, foraging preference, variations between subspecies, monitoring methods as well as the possible methods for controlling this behaviour. As concluded from this review, more work needs to be performed in order to elucidate certain aspects of foraging behaviour. [ABSTRACT FROM AUTHOR]

The article focuses on a study conducted to examine non-pharmacologic treatments for fear of flying. It si noted that treatment programs for fear of flying, including combined treatment, Hypnotherapy, EMDR, Relaxation and cognitive behavioral treatment are offered by a growing number of treatment facilities.

Abstract: There are no clear, evidence-based guidelines that dictate when it is safe for a patient to fly after sustaining a midface fracture. From January 2006 to December 2009, the Royal Darwin Hospital Maxillofacial Unit had 48 out of 201 patients with an orbital fracture that involved a paranasal air sinus transported by a variety of aircraft to the unit for definitive management. No orbital complications were recorded for the 24% of patients requiring air travel to our tertiary referral centre. Furthermore, there were no recorded deviations from the standard flight plan. We believe that this demonstrates there are no absolute contraindications to flying on a variety of aircraft with a midface fracture, but clinical assessment remains crucial for an informed decision to transport these patients by air. [Copyright &y& Elsevier]

Abstract: Squid not only swim, they can also fly like rockets, accelerating through the air by forcefully expelling water out of their mantles. Using available lab and field data from four squid species, Sthenoteuthis pteropus, Dosidicus gigas, Illex illecebrosus and Loligo opalescens, including sixteen remarkable photographs of flying S. pteropus off the coast of Brazil, we compared the cost of transport in both water and air and discussed methods of maximizing power output through funnel and mantle constriction. Additionally we found that fin flaps develop at approximately the same size range as flight behaviors in these squids, consistent with previous hypotheses that flaps could function as ailerons whilst aloft. S. pteropus acceleration in air (265 body lengths [BL]/s2; 24.5m/s2) was found to exceed that in water (79BL/s2) three-fold based on estimated mantle length from still photos. Velocities in air (37BL/s; 3.4m/s) exceed those in water (11BL/s) almost four-fold. Given the obvious advantages of this extreme mode of transport, squid flight may in fact be more common than previously thought and potentially employed to reduce migration cost in addition to predation avoidance. Clearly squid flight, the role of fin flaps and funnel, and the energetic benefits are worthy of extended investigation. [Copyright &y& Elsevier]

Encouraging positive public behaviour change has been touted as a pathway for mitigating the climate impacts of air travel. There is, however, growing evidence that two gaps, one between attitudes and behaviour, and the other between practices of “home” and “away”, pose significant barriers to changing discretionary air travel behaviour. This paper uses both modern sociological theory on tourism as liminoid space, and postmodern theory that views identities as contextual, to provide a deeper understanding of why these gaps occur in the context of tourism spaces. Based on 50 in-depth consumer interviews in Australia, Norway and the United Kingdom, our findings confirm that tourism spaces are often subject to lower levels of environmental concern than daily domestic contexts. The majority of participants reduced, suppressed or abandoned their climate concern when in tourism spaces, and rationalised their resulting behavioural contradictions. Only a minority held there was no difference between the environmental sustainability of their practices in domestic situations versus those on holiday. These findings suggest that scope for voluntary positive behaviour change in the air travel context is limited and will not come without stronger intervention, which is a key finding for policy makers seeking reductions in air travel's climate impacts. [ABSTRACT FROM PUBLISHER]

Squid have been studied extensively since 1982 to quantitatively measure their cost of locomotion and compare it with costs for fishes that are their primary competitors in the ocean. Early work focused on oxygen consumption in swim tunnels and led to the use of jet pressure tags to relate captive studies to behaviour in nature. Dosidicus gigas (d'Orbigny, 1835) (jumbo flying squid or Humboldt squid), which has expanded its range more than 10-fold, is used to illustrate how 'live fast, die young' squid can out compete fishes in changing times by both swimming and flying. Recent work has provided quantitative data on the costs of flying and this report provides some comparisons. Costs of flight in nature require new technology, which has fortunately arrived just in time. Accelerometry tags can now provide similar and perhaps better data on travel rate in nature, both in water and in air. These work on both squid and fish, so more and better comparisons are becoming possible. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although images of rock and stone play a significant role in Nietzsche’s thinking, from his earliest writings to his ideas inThus Spoke Zarathustraabout will to power and eternal return, this stratum of his imagery has not been much discussed. Initially rocks come across as ‘witnesses of prehistory that are eager to acquire language’, as well as border markers of, and means of entry to, the ‘dead world’, or inanimate realm. Later, stone becomes an image of the raw material that we have to work if we want to make something of our lives by fashioning them, which we can do with all strata of the soul except the deepest. At that level granite signifies what is unalterable, being the sedimentation of a very long past, and so rock comes to be associated with the past that is recalcitrant in the face of will. But when will can will as will to power, stone takes part in the play that is the consummate affirmation of life. It also has to be a dance, a dance on the force-field of will to power, overcoming for the moment the Spirit of Heaviness by lifting lightly from the earth. And finally flight: when ‘the boundary stones themselves fly into the air’, with a few of us shifting along with them. [ABSTRACT FROM AUTHOR]

The Reformed Church in America is wrestling with an interesting question in ecclesiology and church order: is there a place within the church for so-called non-geographic classes. Non-geographic classes are classes which are not formed around a geographic regional principal, but by agreement in theological perspective or a peculiar way that a congregation is shaped. The question central to this article is then: is there a place in Reformed churches for non-geographical classes? In answering this question, the following will be considered: a similar proposal from the Gereformeerde Bond in the Netherlands Reformed Church in 1998; the geographic-regional principle; the Walloon Classis; the Classis of Holland; the Reformed Church in America; Flying, diocesan and titular bishops and finally a conclusion. [ABSTRACT FROM AUTHOR]

Abstract: When advising a syncope patient about resumption of driving, flying or vocational activities, physicians must consider relevant laws and regulations, the etiology of the syncope, and the risk of recurrence and the impact of recurrence on the safety of the patient and others. Guidelines from professional cardiology societies may aid the physician. In the United States, private driving is regulated by individual states and their laws show significant variance. Commercial driving and flying are regulated at the federal level. These regulations tend to be more uniform, but are significantly stricter due to the potential risk to the public posed by commercial drivers or pilots with syncope. For many diagnoses, both regulations and professional society recommendations incorporate an observation period following the index syncopal event. This is due to the natural history of syncope recurrence and to allow time to monitor the response to treatment. [Copyright &y& Elsevier]

Copyright of Religion & Culture / Religija ir Kultura is the property of Vilnius University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: In the fight against discrimination, the IDF launched the first ever International Charter of Rights and Responsibilities of People with Diabetes in 2011: a balance between rights and duties to optimize health and quality of life, to enable as normal a life as possible and to reduce/eliminate the barriers which deny realization of full potential as members of society. It is extremely frustrating to suffer blanket bans and many examples exist, including insurance, driving licenses, getting a job, keeping a job and family affairs. In this article, an example is given of how pilots with insulin treated diabetes are allowed to fly by taking the responsibility of using special blood glucose monitoring protocols. At this time the systems in the countries allowing flying for pilots with insulin treated diabetes are applauded, particularly the USA for private flying, and Canada for commercial flying. Encouraging developments may be underway in the UK for commercial flying and, if this materializes, could be used as an example for other aviation authorities to help adopt similar protocols. However, new restrictions implemented by the new European Aviation Authority take existing privileges away for National Private Pilot Licence holders with insulin treated diabetes in the UK. [Copyright &y& Elsevier]

Abstract: Aim: To conduct a survey in a representative cohort of ambulatory patients with stable, well managed chronic heart failure (CHF) to discover their experiences of air travel. Methods: An expert panel including a cardiologist, an exercise scientist, and a psychologist developed a series of survey questions designed to elicit CHF patients'' experiences of air travel (Appendix 1). The survey questions, information sheets and consent forms were posted out in a self-addressed envelope to 1293 CHF patients. Results: 464 patients (response rate 39%) completed the survey questionnaires. 54% of patients had travelled by air since their heart failure diagnosis. 20% of all patients reported difficulties acquiring travel insurance. 65% of patients who travelled by air experienced no health-related problems. 35% of patients who travelled by air experienced health problems, mainly at the final destination, going through security and on the aircraft. 27% of all patients would not travel by air in the future. 38% of patients would consider flying again if there were more leg room on the aeroplane, if their personal health improved (18%), if they could find cheaper travel insurance (19%), if there were less waiting at the airport (11%), or if there were less walking/fewer stairs to negotiate at the airport (7%). Conclusion: For most patients in this sample of stable, well managed CHF, air travel was safe. [Copyright &y& Elsevier]

Banni is an ecologically important area with respect to the presence of large number of bird species and their distribution in different types of habitat patches. Animals are engaged in various activities in different ways to survive successfully in different habitat condition. In view of this, the present study conducted for observing the activities of five sympatric birds in Banni area to understand their involvement in various basic activities. The activities of five sympatric birds, commonly found in Banni area were observed in pre-designed transect by applying scan sampling method. It was observed that, most of the individuals of all sympatric bird engaged in flying and resting except short-toed lark, having very less proportion of individual engaged in resting. It was also observed that, a small number of individuals of all sympatric bird engaged in walking activity. A significant difference found in all activities recorded between the sympatric birds of Banni except the walking activity. In conclusion, the result of the activity budget highlights that the sympatric bird were more involved in flying and resting, and less involve in walking and fighting due to the group size and presence of minimum human disturbances in Banni. The present study also suggests that more intensive study is needed to find out the activity variation according to the habitat and group size of birds. [ABSTRACT FROM AUTHOR]

Summary: This is the second of a two part review which critically evaluates research published in disparate sources into the psychological treatment of fear of flying. Part I established fear of flying as a complex heterogeneous clinical phenomenon. This paper discusses the way in which evidence from clinical trials translates to best practice in treating fear of flying. Published research on psychological interventions uses terminology which bears a close resemblance to cognitive behavioural therapy. It is, however, questionable whether some treatment approaches reflect the implementation of the cognitive behavioural model as it is described in the wider literature on the treatment of anxiety disorders. This review evaluates a synthesis of published research which considers fear of flying and related anxiety disorders with the aim of deriving best practice. It concludes that the most effective psychological interventions will be those based on an accurate functional assessment of an individual and their social context relevant to fear of flying and not merely a set of standard and invariant protocols. Most published research has been carried out on participants who self refer or volunteer for treatment and it is probable that this is a biased clinical group which may distort reported efficacy and treatment outcomes. It concludes by highlighting directions for future research and the development of psychological treatments for fear of flying. [Copyright &y& Elsevier]

Summary: Fear of flying, its nature, prevalence, etiology and treatment, has been the subject of a substantial quantity of research over the past 30 years. With the exception of a dated review of treatment methods however, there has been no evaluation of this expanding body of evidence, its contribution to theory and influence on clinical practice. Published research has also generally failed to apply developments in the understanding and treatment of anxiety disorders generally to fear of flying. This review provides a critical evaluation of the existing literature and what it reveals about theory and practice. It does this from the perspective of Cognitive Behavioural Therapy. The evidence reviewed demonstrates that fear of flying is a heterogeneous phenomenon which is acquired under the influence of complex psychological, social and physiological factors unique to each affected individual. Effective psychological interventions must therefore be founded on a comprehensive functional assessment of each individual, a finding which is considered in detail in the second part of this review. [Copyright &y& Elsevier]

Modern jet transport aircraft are typically flown using the on-board automation by the pilot programming commands into the auto-flight systems. Anecdotal evidence exists suggesting that pilots of highly automated aircraft experience manual flying skills decay as a result of a lack of opportunity to practise hand-flying during line operations. The ability of a pilot to revert to basic manual control is essential, for example, in cases where the aircraft's automatic capability is diminished or when reconfiguring the automatics is an ineffective use of crew capacity. However, there is a paucity of objective data to substantiate this perceived threat to flight safety. Furthermore, traditional performance measurement techniques may lack the ability to identify subtle but significant differences in pilots' manual handling ability in large transport aircraft. This study examines the relationship between pilot manual handling performance and their recent flying experience using both traditional flight path tracking measures and frequency-based control strategy measures. Significant relationships are identified between pilots' very recent flying experience and their manual control strategy. Statement of Relevance: The study demonstrates a novel application of frequency analysis, which produces a broader and more sensitive analysis of pilot performance than has been offered in previous research. Additionally, the relationships that are found to exist between recent flying experience and manual flying performance will help to guide future pilot assessment and training. [ABSTRACT FROM AUTHOR]

Abstract: Information seeking is completely ignored in research on aviation psychology and more generally in issues of air transport safety. But information seeking occupies a central place in the pilots’ work. And this activity is undergoing an important development: the transition from paper to electronic documents. A contribution to the assessment of this transition is presented here. The assessment is focused on deterioration of information access, understanding and exploitation, and their possible negative consequences in terms of reliability. The exploitation of the documentation by pilots, and particularly the information seeking activity, are described and linked to their contexts (i.e. the main tasks of flying that require information seeking). Then an users test is presented where some information-seeking tasks are evaluated in terms of cost and errors, by comparing electronic and paper documents. The results show that electronic documents provide new functions that seem useful but also that too many new functions generate difficulties. Then it seems that pilots need some time to learn how to use these new documents. Reducing attention needed to perform a task such as calculation is risky. Some aspects of information seeking by the pilots should be better analysed and evaluated. [Copyright &y& Elsevier]

'Are you going to tell me off for flying?' This question was asked three times by a lady in South Manchester, England, when we asked her to participate in our qualitative in-home study on flying. She asked it once when we approached her in the street to ask if we may interview her. She asked again when we phoned to confirm the time and address of the interview, and she asked it a third time while serving tea and biscuits at the beginning of the interview. Needless to say we had given absolutely no indication that the interview would pass 'judgment' on her flying activities. The lady had undertaken six return trips by air for leisure in the previous year, and in the final section of the interview commented 'I will have a conscience, but I won't not fly to Miami...'. As this one example shows, the frequent flying/environmental impact question is currently a hot topic. It brings forth a cocktail of rich unprompted discussion and a mixed bag of responses, it has become emotionally charged and polemic. Accounts and justifications concerning frequent flying range from surprise that a taken-for-granted everyday activity which until very recently had been considered a culturally desirable thing to do, has suddenly become frowned upon; to a sense of almost guilty pleasure, apology and, at its extremes, defiance. What the significance and explanation for this might be in sociological terms is the focus of this paper. The answers are important, in particular for policy stakeholders seeking to curb consumption behaviours as one of a portfolio of emissions reduction strategies. It is to the policy audience that this paper primarily speaks. It also provides a quite different - out of the box - insight and contribution to the aviation and emissions debate, which complements the more 'supply side' technology and research and development focused papers which dominate the aviation and emissions-reduction literature currently. [ABSTRACT FROM AUTHOR]

I review the concept of optimal vortex formation and examine its relevance to propulsion in biological and bio-inspired systems, ranging from the human heart to underwater vehicles. By using examples from the existing literature and new analyses, I show that optimal vortex formation can potentially serve as a unifying principle to understand the diversity of solutions used to achieve propulsion in nature. Additionally, optimal vortex formation can provide a framework in which to design engineered propulsions systems that are constrained by pressures unrelated to biology. Finally, I analyze the relationship between optimal vortex formation and previously observed constraints on Strouhal frequency during animal locomotion in air and water. It is proposed that the Strouhal frequency constraint is but one consequence of the process of optimal vortex formation and that others remain to be discovered. [ABSTRACT FROM AUTHOR]

Many animals maneuver superbly underwater using their pectoral appendages. These animals range from sunfish, which have flexible, low aspect ratio fins, to penguins, which have relatively stiff, high aspect ratio wings. Biorobotics is a means of gaining insight into the mechanisms these animals use for maneuvering. In this study, experiments were carried out with models of abstracted penguin wings, and hydrodynamic characteristics — in particular, efficiency — were measured directly. A cross-flow vortex model of the unsteady force mechanism was developed that can compute instantaneous lift and drag forces accurately. This makes use of the steady characteristics of the fin and proposes that cross-flow drag vortices of bluff bodies in steady flow are analogous to dynamic stall vortices and that fin oscillation is a means for keeping the vortices attached to the fin. From what has been reported for sunfish with pectoral fins to our current measurements for single abstracted penguin wings, we infer that the maximum hydrodynamic efficiency has remained largely unchanged. A selection algorithm was used to rapidly find the fin oscillation parameters for optimum efficiency. Finally, we compared the measurements on the penguin-like relatively stiff fins and the reported flow visualization of flexible sunfish pectoral fins. The flexible pectoral fins of station-keeping sunfish exhibit a rich repertoire of capability such as the formation of dynamic stall vortices simultaneously on two leading edges during part of the cycle, changes in projected area in different planes, and the vectoring of jets. However, such fins may not be scalable to larger biorobotic vehicles and relatively stiff fins appear to be better suited instead, albeit with somewhat limited station-keeping ability. [ABSTRACT FROM AUTHOR]