Travellers with prosthetic limbs, a neglected population. A perspective on what travel health practitioners need to know.

BACKGROUND: The benefits of travel for the wellbeing of people of all ages and abilities are well known, though travellers with prostheses have so far been excluded. Limb loss, due to trauma, vascular disease, cancer, or infections requires a prosthesis for cosmesis and functionality. The life-changing event of losing a limb and the considerable psychological adjustment to accept an altered body image influence rehabilitation and self-management as well as the participation in social activities, such as sport and travel. The challenge of travel lies not only in transferring practical impediments encountered at home to another location; familiar coping strategies may require unexpected adjustments. After presenting background information on limb loss and prostheses, the purpose of this paper was to review literature on health advice for travellers with prosthetic limbs. METHOD: All major data bases were searched for peer-reviewed literature using a variation of keyword combinations around travel and prosthetics. Relevant journals were searched individually, and selected authors and university departments contacted. No evidence-based results were obtained. The search then moved to grey literature including documents from relevant organisations, professional bodies, government websites, manufacturers, airlines, prosthetic/physiotherapy clinics, sport organisations to approaching amputees, including veterans and athletes, directly. RESULT: The list of collated travel advice for people with artificial limbs relates to (1) trip preparation, (2) packing (especially considering the mechanical and/or electrical requirements of the prosthesis), (3) travelling by plane as the most covered mode of travel, and (4) navigating airports and airport security, which may be used by travel health practitioners while awaiting evidence-based guidelines. CONCLUSION: This is the first paper on travel with a prosthetic limb in any field, including travel medicine. Therefore, travel health practitioners have no evidence-based guidelines at their disposal required for high-quality care for this neglected population. Preliminary recommendations for clinical practice, advice for required updates in education, and suggestions for urgently needed research are provided to replace current hints and tips with evidence so that travellers with prostheses are no longer 'out on a limb'.

A Safety Approach for Improving Security - Effective Coordination Strategies at the Airport Security Screening Checkpoint.

OBJECTIVE: This study aimed to analyze effective teamwork at security checkpoints by investigating how security crews communicate in different (routine and threat) situations. BACKGROUND: Working at an airport security screening checkpoint is challenging. Although tasks and processes are highly regulated and standardized due to legal requirements, security screeners must be trained to deal with unforeseen threat situations involving high levels of uncertainty. Therefore, security crews need to engage in flexible and adaptive coordination according to the situation and circumstances. METHOD: We conducted a field study with 20 airport security screening crews comprising 100 security screeners. Teamwork in terms of interaction between crew members was measured, differentiating between proactive "push" communication and information on request representing "pull" communication. Furthermore, non-task related communication was assessed. RESULTS: While crews showed non-task related communication more in routine situations, both task-related "push" and "pull" communication occurred more in threat situations. In terms of team performance, we could show significant positive effects of proactive "push" communication and non-task related interaction in threat situations. CONCLUSION: Our results underscore the specific setting of airport security screening and the challenges that arise for teamwork. This study investigates professional screeners and passengers in the field. In contrast to other high-risk areas, security crews are confronted with a third party that complicates coordination strategies considered effective in previous studies. APPLICATION: Our findings recommend situation-specific communication strategies for practical training for airport security screening crews.

Drone Model Classification Using Convolutional Neural Network Trained on Synthetic Data.

We present a convolutional neural network (CNN) that identifies drone models in real-life videos. The neural network is trained on synthetic images and tested on a real-life dataset of drone videos. To create the training and validation datasets, we show a method of generating synthetic drone images. Domain randomization is used to vary the simulation parameters such as model textures, background images, and orientation. Three common drone models are classified: DJI Phantom, DJI Mavic, and DJI Inspire. To test the performance of the neural network model, Anti-UAV, a real-life dataset of flying drones is used. The proposed method reduces the time-cost associated with manually labelling drones, and we prove that it is transferable to real-life videos. The CNN achieves an overall accuracy of 92.4%, a precision of 88.8%, a recall of 88.6%, and an f1 score of 88.7% when tested on the real-life dataset.

Simulation of Air Travel-Related Irradiation Exposure of Cryopreserved Mouse Germplasm Samples.

Cryopreservation of genetically modified mouse lines prevents the loss of specific mutants that are of enormous scientific value for both basic and applied research. Cryopreservation of spermatozoa or preimplantation embryos enables discontinuation of breeding as well as archiving of specific lines for future studies. Regarding active inter-laboratory exchange of mutants, cryopreserved material is more advantageous to transport than live animals. However, transportation stress should not be trivialized. Security scanning of transport boxes at airports and customs, in particular, as well as additional cosmic radiation, pose a threat to undefined dosages of irradiation exposure. To simulate this, cryopreserved samples of mouse spermatozoa and preimplantation embryos were exposed to an X-ray dosage of 1 mGy in an X-ray machine. For subsequent investigation of the cell integrity of irradiated spermatozoa and embryos, spermatozoa forward motility as well as embryo developmental capacity and apoptosis values were examined and compared with nonirradiated control samples. The percentage of forward-moving spermatozoa per sample appears to be significantly reduced after irradiation exposure. The in vitro developmental capacity of preimplantation embryos as well as their relative share of apoptotic cells do not seem to be influenced by irradiation exposure. This leads to the assumption that, at least in preimplantation embryos, X-ray dosages of 1 mGy do not induce sudden severe cellular harm. Nevertheless, stochastic effects of ionizing irradiation, such as mutations, do not have a dosage threshold and always represent the potential danger of alterations to cells and cellular components, especially the DNA. This could lead to undefined mutations inducing genetic drift, in the worst case to the loss of a mutant line. We therefore strongly recommend minimizing "transportation stress," in particular by irradiation exposure, to keep its potential consequences in mind, and to standardize shipping procedures.

Evaluating the Perceived Efficacy of Randomized Security Measures at Airports.

Both the increase in traveler numbers and the heightened threat posed by terrorism in recent years represent significant challenges to airport security measures. To ensure that a high level of security is maintained, randomized security checks have been proposed as a promising alternative to traditional security approaches. The use of randomized checks means that only a specific number of people are selected for security screening. However, the likely effects of such a change in security procedures on travelers' security perceptions and on the deterrence of criminal activities remain unclear. Thus, the present study examines how varying the percentage of people screened during security checks influences people's security perceptions. In two online experiments, the participants were asked to imagine that they sought to smuggle an explosive dummy past an airport security check. The only information provided was the number of people screened during security checks, which was manipulated between-subjects in the first experiment and within-subjects in the second experiment. The participants then had to rate their security perception (i.e., the perceived likelihood of successfully smuggling the explosive dummy). The findings show that people perceive traditional security checks to be safer than randomized checks, irrespective of whether 90% or 30% of people are screened. Hence, if randomized security checks would indeed be implemented, it would automatically lead to a decreased perception of security. Furthermore, this decreased security perception might lead to an actual reduction in security, as the deterrence of criminal activities could also be reduced.

Automation reliability, human-machine system performance, and operator compliance: A study with airport security screeners supported by automated explosives detection systems for cabin baggage screening.

Using a simulated X-ray screening task, we tested 122 airport security screeners working with the support of explosives detection systems for cabin baggage screening (EDSCB) as low-level automation. EDSCB varied systematically on three automation reliability measures: accuracy, d', and positive predictive value (PPV). Results showed that when unaided performance was high, operator confidence was high, and automation provided only small benefits. When unaided performance was lower, operator confidence was lower, and automation with higher d' provided large benefits. Operator compliance depended on the PPV of automation: We found lower compliance for lower PPV. Automation with a high false alarm rate of 20% and a low PPV of .3 resulted in operators ignoring about one-half of the true automation alarms on difficult targets-a strong cry-wolf effect. Our results suggest that automation reliability described by d' and PPV is more valid than using accuracy alone. When the PPV is below .5, operators should receive clear instructions on how to respond to automation alarms.

Work design for airport security officers: Effects of rest break schedules and adaptable automation.

This study investigated whether there is empirical support for the current EU regulation mandating breaks of at least 10 min after each period of 20 min continuously reviewing X-ray images in airport security screening. As a second goal, it examined whether providing more autonomy to airport security officers (in the form of spontaneous rest breaks and adaptable automation) would improve their performance and subjective state. Seventy-two student participants had to indicate the presence (or absence) of a threat item (either a gun or a knife) in a series of grey-scaled X-ray images of cabin baggage. Three work-rest schedules were examined: spontaneous breaks (i.e. participants could take breaks at any time), two 5-min breaks and two 10-min breaks during a 1-h testing session. Furthermore, half of the participants were assisted in their task by an adaptable support system offering three levels of automation: (1) no support, (2) cues indicating the presence of a potential threat item, and (3) cues indicating the exact location of a potential threat item. Results showed no performance differences between break regimes, which suggests that there may be viable alternatives to the current EU regulations. It also emerged that providing participants with adaptable automation did not lead to better detection performance but resulted in a less positive response bias than participants without automatic support. Implications for current aviation security regulations are discussed.

Expertise, Automation and Trust in X-Ray Screening of Cabin Baggage.

X-ray screening of passenger baggage is a key component in aviation security. The current study investigated how experts and novices performed in an X-ray baggage screening task while being assisted by an adaptable diagnostic aid. Furthermore, it examined how both groups operated and trusted this automated system. 30 experts (certified screeners) and 31 novices (students) had to indicate whether a target item (either a knife or a gun) was present in a series of X-ray images of cabin baggage. Half of the participants could choose between three different support levels of the diagnostic aid (DA): (1) no support, (2) a cue indicating the presence of a potential target without locating it, or (3) a cue indicating the presence of a potential target by surrounding it with a red frame. As expected, experts achieved higher detection performance (d'), were more self-confident and felt more competent in achieving the task than novices. Furthermore, experts experienced less time pressure and fatigue. Although both groups used the DA in a comparable way (in terms of support level used and frequency of level switches), results showed a performance increase for novices working with the DA compared to novices without support. This benefit of DA was not observed for experts. Interestingly, despite no difference in perceived trust ratings, experts were more compliant (i.e., following DA recommendations when it indicated the presence of a target) and reliant (i.e., following DA recommendations when it indicated the absence of a target) than novices. Altogether, the results of the present study suggested that novices benefited more from a DA than experts. Furthermore, compliance and reliance on DA seemed to depend on expertise with the task. Since experts should be better at assessing the reliability of the DA than novices, they may have used the DA as 'back-up' to confirm their decisions based on expertise (confirmatory function), while novices may have used it as a guide to base their decisions on (support function). Finally, trust towards a DA was associated with the degree to which participants found the DA useful.

Automation in airport security X-ray screening of cabin baggage: Examining benefits and possible implementations of automated explosives detection.

Bomb attacks on civil aviation make detecting improvised explosive devices and explosive material in passenger baggage a major concern. In the last few years, explosive detection systems for cabin baggage screening (EDSCB) have become available. Although used by a number of airports, most countries have not yet implemented these systems on a wide scale. We investigated the benefits of EDSCB with two different levels of automation currently being discussed by regulators and airport operators: automation as a diagnostic aid with an on-screen alarm resolution by the airport security officer (screener) or EDSCB with an automated decision by the machine. The two experiments reported here tested and compared both scenarios and a condition without automation as baseline. Participants were screeners at two international airports who differed in both years of work experience and familiarity with automation aids. Results showed that experienced screeners were good at detecting improvised explosive devices even without EDSCB. EDSCB increased only their detection of bare explosives. In contrast, screeners with less experience (tenure < 1 year) benefitted substantially from EDSCB in detecting both improvised explosive devices and bare explosives. A comparison of all three conditions showed that automated decision provided better human-machine detection performance than on-screen alarm resolution and no automation. This came at the cost of slightly higher false alarm rates on the human-machine system level, which would still be acceptable from an operational point of view. Results indicate that a wide-scale implementation of EDSCB would increase the detection of explosives in passenger bags and automated decision instead of automation as diagnostic aid with on screen alarm resolution should be considered.

Automation in visual inspection tasks: X-ray luggage screening supported by a system of direct, indirect or adaptable cueing with low and high system reliability.

The present study evaluated three automation modes for improving performance in an X-ray luggage screening task. One hundred and forty participants were asked to detect the presence of prohibited items in X-ray images of cabin luggage. Twenty participants conducted this task without automatic support (control group), whereas the others worked with either indirect cues (system indicated the target presence without specifying its location), or direct cues (system pointed out the exact target location) or adaptable automation (participants could freely choose between no cue, direct and indirect cues). Furthermore, automatic support reliability was manipulated (low versus high). The results showed a clear advantage for direct cues regarding detection performance and response time. No benefits were observed for adaptable automation. Finally, high automation reliability led to better performance and higher operator trust. The findings overall confirmed that automatic support systems for luggage screening should be designed such that they provide direct, highly reliable cues.Practitioner summary: The present study confirmed previous findings showing better detection performance in X-ray images of luggage when supported by automation providing direct, highly reliable cues. Furthermore, participants used adaptable automation only to select their preferred level of automation. This behaviour did not provide the benefits expected under adaptable automation.

Detection of total hip arthroplasties at airport security checkpoints - how do updated security measures affect patients?

INTRODUCTION: There have been historical reports on the experiences of patients with total hip arthroplasty (THA) passing through standard metal detectors at airports. The purpose of this study was to analyse those who had recently passed through airport security and the incidence of: (i) triggering of the alarm; (ii) extra security searches; and (iii) perceived inconvenience. METHODS: A questionnaire was given to 125 patients with a THA during a follow-up appointment. Those who had passed through airport security after January 2014 met inclusion criteria. A survey was administered that addressed the number of encounters with airport security, frequency of metal detector activation, additional screening procedures utilised, whether security officials required prosthesis documentation, and perceived inconvenience. RESULTS: 51 patients met inclusion criteria. 10 patients (20%) reported triggered security scanners. 4 of the 10 patients stated they had surgical hardware elsewhere in the body. 13 of the 51 patients (25%) believed that having their THA increased the inconvenience of traveling. This is different from the historical cohort with standard metal detectors which patients reported a greater incidence of alarm triggering (n = 120 of 143; p = 0.0001) and perceived inconvenience (n = 99 of 143; p = 0.0001). DISCUSSIONS: The percentage of patients who have THA triggering security alarms has decreased. Furthermore, the number of patients who feel that their prosthesis caused traveling inconvenience has decreased. We feel that this decrease in alarms triggered and improved perceptions about inconvenience are related to the increased usage of new technology.

Patients with mental problems - the most defenseless travellers.

BACKGROUND: Severe mental illness occurring abroad is a difficult situation for patients, their families, and for the local medical community. Patients with mental problem are doublely stigmatized due to their mental illness and because they are foreigners in an unfamiliar country. The appropriate treatment is often delayed, while patients are often dealt with in a manner that violates their human rights. Moreover, repatriation - which is vital in this case - is often delayed due to the lack of international protocols for the transportation and treatment of mentally ill travelers. METHODS: Authors analyzed several factors related to acute mental health problems during travel: the etiology of symptoms, the appropriate treatment possibilities abroad, and medical evacuation and repatriation of the psychotic patient. The article presents a brief review of travel-related mental disorders, the epidemiology of mental health issues faced by travelers, and the significance of pre-travel advice for these patients. The first problem is to recognize (and redress) the particular challenges faced by a psychotic patient in a strange country. The second challenge is to prepare the patients, often in a poor psychiatric state, for medical evacuation by commercial aircraft. Another important question is the best way to take the patient through customs and security control. All of these, as yet unresolved, issues can make the mental patient virtually defenseless. CONCLUSIONS: Although timely repatriation of a mentally ill patient is vital and urgent, most travel insurance policies exclude treatment and repatriation costs incurred due to acute mental illness. The high cost of treatment and repatriation must be paid by the patient or their family, which could lead to severe financial strain or insolvency. Changing the approaches taken by the local mental health care community, police, airport security, and insurance companies remain a challenge for psychiatrists.

When and Why Threats Go Undetected: Impacts of Event Rate and Shift Length on Threat Detection Accuracy During Airport Baggage Screening.

OBJECTIVE: We aimed to assess the impact of task demands and individual characteristics on threat detection in baggage screeners. BACKGROUND: Airport security staff work under time constraints to ensure optimal threat detection. Understanding the impact of individual characteristics and task demands on performance is vital to ensure accurate threat detection. METHOD: We examined threat detection in baggage screeners as a function of event rate (i.e., number of bags per minute) and time on task across 4 months. We measured performance in terms of the accuracy of detection of Fictitious Threat Items (FTIs) randomly superimposed on X-ray images of real passenger bags. RESULTS: Analyses of the percentage of correct FTI identifications (hits) show that longer shifts with high baggage throughput result in worse threat detection. Importantly, these significant performance decrements emerge within the first 10 min of these busy screening shifts only. CONCLUSION: Longer shift lengths, especially when combined with high baggage throughput, increase the likelihood that threats go undetected. APPLICATION: Shorter shift rotations, although perhaps difficult to implement during busy screening periods, would ensure more consistently high vigilance in baggage screeners and, therefore, optimal threat detection and passenger safety.

Stress-induced cortisol secretion impairs detection performance in x-ray baggage screening for hidden weapons by screening novices.

Aviation security strongly depends on screeners' performance in the detection of threat objects in x-ray images of passenger bags. We examined for the first time the effects of stress and stress-induced cortisol increases on detection performance of hidden weapons in an x-ray baggage screening task. We randomly assigned 48 participants either to a stress or a nonstress group. The stress group was exposed to a standardized psychosocial stress test (TSST). Before and after stress/nonstress, participants had to detect threat objects in a computer-based object recognition test (X-ray ORT). We repeatedly measured salivary cortisol and X-ray ORT performance before and after stress/nonstress. Cortisol increases in reaction to psychosocial stress induction but not to nonstress independently impaired x-ray detection performance. Our results suggest that stress-induced cortisol increases at peak reactivity impair x-ray screening performance.

Context matters: the structure of task goals affects accuracy in multiple-target visual search.

Career visual searchers such as radiologists and airport security screeners strive to conduct accurate visual searches, but despite extensive training, errors still occur. A key difference between searches in radiology and airport security is the structure of the search task: Radiologists typically scan a certain number of medical images (fixed objective), and airport security screeners typically search X-rays for a specified time period (fixed duration). Might these structural differences affect accuracy? We compared performance on a search task administered either under constraints that approximated radiology or airport security. Some displays contained more than one target because the presence of multiple targets is an established source of errors for career searchers, and accuracy for additional targets tends to be especially sensitive to contextual conditions. Results indicate that participants searching within the fixed objective framework produced more multiple-target search errors; thus, adopting a fixed duration framework could improve accuracy for career searchers.

Prevalence effects in newly trained airport checkpoint screeners: trained observers miss rare targets, too.

Many socially important search tasks are characterized by low target prevalence, meaning that targets are rarely encountered. For example, transportation security officers (TSOs) at airport checkpoints encounter very few actual threats in carry-on bags. In laboratory-based visual search experiments, low prevalence reduces the probability of detecting targets (Wolfe, Horowitz, & Kenner, 2005). In the lab, this "prevalence effect" is caused by changes in decision and response criteria (Wolfe & Van Wert, 2010) and can be mitigated by presenting a burst of high-prevalence search with feedback (Wolfe et al., 2007). The goal of this study was to see if these effects could be replicated in the field with TSOs. A total of 125 newly trained TSOs participated in one of two experiments as part of their final evaluation following training. They searched for threats in simulated bags across five blocks. The first three blocks were low prevalence (target prevalence ≤ .05) with no feedback; the fourth block was high prevalence (.50) with full feedback; and the final block was, again, low prevalence. We found that newly trained TSOs were better at detecting targets at high compared to low prevalence, replicating the prevalence effect. Furthermore, performance was better (and response criterion was more "liberal") in the low-prevalence block that took place after the high-prevalence block than in the initial three low-prevalence blocks, suggesting that a burst of high-prevalence trials may help alleviate the prevalence effect in the field.