Design and assembly of a magneto-inertial wearable device for ecological behavioural analysis of infants

There are recent evidence which show how brain development is strictly linked to the action. Movements shape and are, in turn, shaped by cortical and sub-cortical areas. In particular spontaneous movements of newborn infants matter for developing the capability of generating voluntary skill movements. Therefore studying spontaneous infants’ movements can be useful to understand the main developmental milestones achieved by humans from birth onward. This work focuses on the design and development of a mechatronic wearable device for ecological movement analysis called WAMS (Wrist and Ankle Movement Sensor). The design and assembling of the device is presented, as well as the communication protocol and the synchronization with other marker-based optical movement analysis systems

Inertial-Magnetic Sensors for Assessing Spatial Cognition in Infants

This paper describes a novel approach to the assessment of spatial cognition in children. In particular we present a wireless instrumented toy embedding magneto-inertial sensors for orientation tracking, specifically developed to assess the ability to insert objects into holes. To be used in naturalistic environments (e.g. daycares), we also describe an in-field calibration procedure based on a sequence of manual rotations, not relying on accurate motions or sophisticated equipment. The final accuracy of the proposed system, after the mentioned calibration procedure, is derived by direct comparison with a gold-standard motion tracking device. In particular, both systems are subjected to a sequence of ten single-axis rotations (approximately 90 deg, back and forth), about three different axes. The root-mean-square of the angular error between the two measurements (gold-standard vs. proposed systems) was evaluated for each trial. In particular, the average rms error is under 2 deg. This study indicates that a technological approach to ecological assessment of spatial cognition in infants is indeed feasible. As a consequence, prevention through screening of large number of infants is at reach

Complete Phase Diagram of DNA Unzipping: Eye, Y-fork and triple point

We study the unzipping of double stranded DNA (dsDNA) by applying a pulling force at a fraction $s$ $(0 \le s \le 1)$ from the anchored end. From exact analytical and numerical results, the complete phase diagram is presented. The phase diagram shows a strong ensemble dependence for various values of $s$. In addition, we show the existence of an ``eye'' phase and a triple point.Comment: 4 pages, 4 figures; revised version: misprints corrected. References corrected/added. To appear in Physical Review Letter

Methodological factors influencing measurement and processing of plasma reelin in humans

BACKGROUND: Reelin, intensively studied as an extracellular protein that regulates brain development, is also expressed in a variety of tissues and a circulating pool of reelin exists in adult mammals. Here we describe the methodological and biological foundation for carrying out and interpreting clinical studies of plasma reelin. RESULTS: Reelin in human plasma was sensitive to proteolysis, freeze-thawing and heating during long-term storage, sample preparation and electrophoresis. Reelin in plasma was a dimer under denaturing conditions. Boiling of samples resulted in laddering, suggesting that each of the 8 repeats expressed in reelin contains a heat-labile covalent bond susceptible to breakage. Urinary-type and tissue-type plasminogen activator converted reelin to a discrete 310 kDa fragment co-migrating with the major immunoreactive reelin fragment seen in plasma and also detected in brain. (In contrast, plasmin produced a spectrum of smaller unstable reelin fragments.) We examined archival plasma of 10 pairs of age-matched male individuals differing in repeat length of a CGG repeat polymorphism of the 5'-untranslated region of the reelin gene (both alleles < 11 repeats vs. one allele having >11 repeats). Reelin 310 kDa band content was lower in subjects having the long repeats in all 10 pairs, by 25% on average (p < 0.001). In contrast, no difference was noted for amyloid precursor protein. CONCLUSIONS: Our studies indicate the need for caution in measuring reelin in archival blood samples, and suggest that assays of plasma reelin should take into account three dimensions that might vary independently: a) the total amount of reelin protein; b) the relative amounts of reelin vs. its proteolytic processing products; and c) the aggregation state of the native protein. Reelin-plasminogen activator interactions may affect their roles in synaptic plasticity. Our results also suggest that the human CGG repeat polymorphism affects reelin gene expression, and may affect susceptibility to human disease

Dimensionality Assessment of Fatigue in Collegiate Aviation Operations: A Structural Equation Modeling Approach

There have been recommendations for evidence-based studies into the safety risk posed by fatigue in the flight training environment from the International Civil Aviation Organization (ICAO), National Transportation Safety Board (NTSB) and the Federal Aviation Administration (FAA). Extant research suggests a paucity of studies on the dimensionality of fatigue in collegiate aviation when compared to scheduled service and military flight operations. As a unique population, collegiate aviation pilots have rigorous course schedules that require intensive studying. Many pilots in this population are active in campus student organization activities and often have part time jobs. These conditions may exacerbate fatigue risks. Research suggests relationships between fatigue and judgment errors, aircraft accidents and incidents, poor academic performance, and undesirable health metrics. An assessment of explanatory factors underlying fatigue in collegiate aviation is essential to better understand fatigue in a flight training environment as well as to develop effective controls. The Collegiate Aviation Fatigue Inventory-II (CAFI-II) was distributed to eight accredited 14 CFR Part 141 four-year degree-awarding universities (n = 422). Using structural equation modeling (SEM), the data provided evidence that there are significant predictive relationships between all the factors examined and fatigue. Results provided a good fit model of the validated CAFI-II inventory for assessing fatigue in collegiate flight operations. Presenters will also engage with the audience and discuss improved fatigue training opportunities and fatigue management efforts

Understanding Fatigue Within a Collegiate Aviation Program

Objective: The purpose of this study was fivefold: to investigate the symptoms that would prompt collegiate aviation pilots perceive they are fatigued; to investigate the time of the day they are most fatigued; to investigate their academic and personal schedules; to investigate the methods collegiate aviation pilots utilize to ensure they are fit to fly; and to investigate whether they have received any academic and/or flight fatigue identification and management training. Background: Fatigue is a pervasive safety hazard in aviation affecting several aspects of flight crew members’ ability to perform their job. Fatigue in aviation and its consequences has been researched across military and commercial operations, but until now Part 141 collegiate aviation pilots have been neglected. Method: Data were collected using an online survey questionnaire self-report questionnaire (N = 122) consisting of items investigating fatigue identification and management by Part 141 collegiate aviation pilots. Results: Sixty percent of the participants usually experience the mental and physical symptoms of fatigue during flight activities. A finding of concern was that 43% of the participants indicated they had not received any training in fatigue identification and management during ground and flight activities. Conclusion: The safety management of fatigue in a Part 141 collegiate aviation environment is a safety issue that warrants further research, and training and education

Fatigue Identification and Management in Flight Training: An Investigation of Collegiate Aviation Pilots

Objective: The purpose of this study was to evaluate collegiate aviation students’ self-awareness of their fatigue issues; to investigate possible causes of fatigue afflicting collegiate aviation students; and to investigate the collegiate aviation students’ lifestyle and perceptions of personal solutions to fatigue. Background: Pilot fatigue is a significant safety hazard in aviation operations. Several factors can contribute to fatigue, including inadequate sleep, long work hours, and inadequate nutritional habits. Some factors, such as social and academic activities, could be unique for Title 14 Code of Federal Regulations (CFR) Part 141 collegiate aviation pilots. Previous studies have addressed fatigue in commercial and military aviation. However, few studies have targeted collegiate aviation students. Method: An online survey questionnaire was utilized to investigate collegiate aviation students’ self-awareness of their fatigue issues; the possible causes of fatigue afflicting those students; their lifestyle as well as their perceptions of personal solutions to fatigue. The population for this study consisted of a subset of the GA community, flight instructors and students from an accredited 14 CFR Part 141 four-year degree-awarding university in the Midwestern region of the United States. Additionally, participants were recruited from a local fixed based operator. Results: Findings indicated that fatigue has played a role during flight training. Pilots had, for example overlooked mistakes because of fatigue. Responses also suggested decrements in alertness and cognitive functions as a result of fatigue. Conclusion: Fatigue is a safety hazard in a collegiate environment that needs addressing. Systematic fatigue education and training, better lifestyle practices, effective workload management, and even a prescriptive approach could significantly enhance aviation safety and the well-being of student pilots

Competency-Based Education: A Framework for a More Efficient and Safer Aviation Industry

Aircraft design and reliability as well as pilots’ education and training have steadily and significantly improved in the last 20 years. Nevertheless, high-profile accidents still occur, even when the aircraft and related systems are operating adequately. Controlled flight into terrain, runway incursion accidents, and loss of control in flight are examples of mishaps in which inadequate decision-making, poor leadership, and ineffective communication are frequently cited as contributing factors. Conversely, the investigation of accidents (e.g., US Airways Flight 1549, in the U.S. on Jan. 15, 2009) and serious incidents (e.g., TAM Linhas Aereas Flight 3756 in Brazil on June 17, 2011) have shown that flight crews must be flexible and adaptable, think outside the box, and communicate effectively to cope with situations well beyond their individual expertise

Collegiate Aviation Pilots: Analyses of Fatigue Related Decision-Making Scenarios

According to Dawson and McCulloch (2005), indicating factors for pilot fatigue may be difficult to ascertain. However, fatigue is a probable cause in 15%-20% of all aircraft accidents (Akerstedt, 2000). It may be assumed fatigue has been important latent condition for many of the general aviation incidents and or accidents but not necessarily identified as a probable cause. Events that barely missed a detrimental situation due to fatigue, often go unnoticed and or unreported. Furthermore, fatigue can influence the quality of flight instruction and flight operations overall. The purpose of the current paper was to examine fatigue related decision-making responses from collegiate aviation pilots. These scenarios were designed to understand mitigation strategies, external pressures, and reasons for go-no-go decisions. Results of the qualitative analysis indicated some pilots were susceptible to organizational pressures, hazardous attitudes, and expressed over reliance on another pilot i.e. a Certified Flight Instructor (CFI). On the contrary, several responses indicated Positive Threat Assessment while Seeking Alternative Solutions. Researchers provided recommended practices, suggested future research, and provided a model to simplify the decision-making process