No second-in-command: human fatigue and the crash of the airship Italia revisited

The dirigible Italia crashed onto the Arctic sea ice north-east of the Svalbard archipelago on 25 May 1928 at 10:33 GMT while travelling back to her base from the North Pole. Only eight of the 16 crew members survived: one was killed upon impact, one did not survive the post-crash ordeal and six were trapped in the airship envelope (i.e., the balloon), which floated away and disappeared. No definite conclusions have ever been reached about the causes of the crash. The judgements of the Commission of Inquiry instituted by the Italian government and published in 1929 are carefully examined. Recent analysis has presented evidence that the mishap may have been fatigue-related. In this paper, the pivotal question of why General Nobile was so sleep-deprived at the time of the accident is addressed, specifically with reference to the lack of a second-in-command (i.e., a deputy commander) during the flight. Such a position was a standard practice for airships at the time, and General Nobile himself described this position as one necessary for an airship. Nevertheless, for a variety of reasons he proceeded on the Italia expedition without an official crew member responsible for this role. The lack of a second-in-command is proposed as a possible major contributing factor in the overall sequence of events leading to the crash of the Italia, although other possible causes and contributing factors for the crash are also considered, including structural failures, crew selection and political obstacles

Fatigue Management Strategies for the Stratospheric Observatory for Infrared Astronomy

Operation of the Stratospheric Observatory for Infrared Astronomy entails a great deal of night-time work, with the potential for both acute and chronic sleep loss, as well as circadian rhythm dysynchrony. Such fatigue can result in performance decrements, with an increased risk of operator error. The NASA Dryden Flight Research Center manages this fatigue risk by means of a layered approach, to include: 1) Education and Training 2) Work Schedule Scoring 3) Obtained Sleep Metrics 4) Workplace and Operational Mitigations and 5) Incident or Accident Investigation. Specifically, quantitative estimation of the work schedule score, as well as the obtained sleep metric, allows Supervisors and Managers to better manage the risk of fatigue within the context of mission requirements

Instrument Display Visual Angles for Conventional Aircraft and the MQ-9 Ground Control Station

Aircraft instrument panels should be designed such that primary displays are in optimal viewing location to minimize pilot perception and response time. Human Factors engineers define three zones (i.e. "cones") of visual location: 1) "Easy Eye Movement" (foveal vision); 2) "Maximum Eye Movement" (peripheral vision with saccades), and 3) "Head Movement" (head movement required). Instrument display visual angles were measured to determine how well conventional aircraft (T-34, T-38, F- 15B, F-16XL, F/A-18A, U-2D, ER-2, King Air, G-III, B-52H, DC-10, B747-SCA) and the MQ-9 ground control station (GCS) complied with these standards, and how they compared with each other. Methods: Selected instrument parameters included: attitude, pitch, bank, power, airspeed, altitude, vertical speed, heading, turn rate, slip/skid, AOA, flight path, latitude, longitude, course, bearing, range and time. Vertical and horizontal visual angles for each component were measured from the pilot s eye position in each system. Results: The vertical visual angles of displays in conventional aircraft lay within the cone of "Easy Eye Movement" for all but three of the parameters measured, and almost all of the horizontal visual angles fell within this range. All conventional vertical and horizontal visual angles lay within the cone of "Maximum Eye Movement". However, most instrument vertical visual angles of the MQ-9 GCS lay outside the cone of "Easy Eye Movement", though all were within the cone of "Maximum Eye Movement". All the horizontal visual angles for the MQ-9 GCS were within the cone of "Easy Eye Movement". Discussion: Most instrument displays in conventional aircraft lay within the cone of "Easy Eye Movement", though mission-critical instruments sometimes displaced less important instruments outside this area. Many of the MQ-9 GCS systems lay outside this area. Specific training for MQ-9 pilots may be needed to avoid increased response time and potential error during flight

Altered social and non-social decision-making in recreational and dependent cocaine users

Background Maladaptive decision-making is assumed to be a core feature of cocaine addiction. Indeed, numerous studies have reported deficits in non-social decision-making tasks and reward-related impulsivity in dependent cocaine users. However, social decision-making has not been examined in cocaine users yet. Moreover, it is unknown if even recreational and non-dependent cocaine use is linked to decision-making deficits. Therefore, we investigated whether recreational and dependent cocaine users exhibit alterations in social and non-social decision-making. Method The performance of healthy controls (n=68), recreational cocaine users (n=68) and dependent cocaine users (n=30) in classical decision-making paradigms (Iowa Gambling Task, Delay Discounting) and in social interaction paradigms (Distribution Game, Dictator Game) was assessed. Results Decisions in the social interaction tasks of both cocaine user groups were more self-serving compared with controls as cocaine users preferred higher monetary payoffs for themselves. In the Iowa Gambling Task, only dependent cocaine users were more likely to choose disadvantageous card decks, reflecting worse decision-making. They were also more likely to choose immediate smaller rewards over larger delayed rewards in the Delay Discounting task. Conclusions Our results imply that both recreational and dependent cocaine users are more concerned with their own monetary gain when interacting with another person. Furthermore, primarily dependent cocaine users are less foresighted and more impulsive regarding immediate reward. Overall, social interaction deficits are already present in recreational users, while non-social decision-making deficits occur predominantly in dependent cocaine users. Thus, social interaction training and cognitive remediation strategies may improve treatment success and quality of life in cocaine dependenc

Fit for Life: Educating About a Healthy Lifestyle in Omaha Elementary Schools

Background: The prevalence of childhood obesity is increasing across the country. Health education at a young age is critical for children to establish healthy habits. The Fit for Life program is put together by Creighton medical students to inspire elementary students to lead a healthy lifestyle. The curriculum integrates physical exercise, real organ demonstrations, emotional wellness exercises, and nutritious meal building to model and encourage healthy habits. Methods: Over four weeks, medical students taught the 4th and 5th graders of two Omaha schools over live video while they followed along with hands-on activities. Before and after the program, students’ height and weight were measured to calculate BMI, and the students completed pre- and post-program quizzes. Paired t-tests were performed to analyze differences in student BMIs and quiz scores. Pre-program quiz scores of students who completed two consecutive years were compared using paired t-tests. Results: Student BMIs before and after the program showed no significant changes (p = 0.479, n = 45) however, quiz scores significantly improved after the program (p \u3c 0.001, n = 44). Self-reported survey responses after the program demonstrate increased motivation for a healthy lifestyle as well as improved understanding of the importance of sleep, exercise, reduced screen time, and healthy eating. Those who completed the program for two consecutive years had significantly higher pre-program quiz scores the second year (p \u3c 0.05, n = 18). Conclusion: Our study found a significant increase in pre- and post-program assessment scores which suggest improvement in student perspective and knowledge of healthy habits. Similarly, students who completed the program for two consecutive years demonstrated an increase in pre-program quiz scores suggesting retention of health knowledge. While there was no significant difference in pre- and post-program BMIs, results may be limited by the duration of the study, given that changes in weight are often insubstantial in the short-term.https://digitalcommons.unmc.edu/chri_forum/1006/thumbnail.jp

Enhancer viruses and a transgenic platform for combinatorial cell subclass-specific labeling

The rapid pace of cell type identification by new single-cell analysis methods has not been met with efficient experimental access to the newly discovered types. To enable flexible and efficient access to specific neural populations in the mouse cortex, we collected chromatin accessibility data from individual cells and clustered the single-cell data to identify enhancers specific for cell classes and subclasses. When cloned into adeno-associated viruses (AAVs) and delivered to the brain by retro-orbital injections, these enhancers drive transgene expression in specific cell subclasses in the cortex. We characterize several enhancer viruses in detail to show that they result in labeling of different projection neuron subclasses in mouse cortex, and that one of them can be used to label the homologous projection neuron subclass in human cortical slices. To enable the combinatorial labeling of more than one cell type by enhancer viruses, we developed a three-color Cre-, Flp- and Nigri- recombinase dependent reporter mouse line, Ai213. The delivery of three enhancer viruses driving these recombinases via a single retroorbital injection into a single Ai213 transgenic mouse results in labeling of three different neuronal classes/subclasses in the same brain tissue. This approach combines unprecedented flexibility with specificity for investigation of cell types in the mouse brain and beyond

A study of indoor carbon dioxide levels and sick leave among office workers

BACKGROUND: A previous observational study detected a strong positive relationship between sick leave absences and carbon dioxide (CO(2)) concentrations in office buildings in the Boston area. The authors speculated that the observed association was due to a causal effect associated with low dilution ventilation, perhaps increased airborne transmission of respiratory infections. This study was undertaken to explore this association. METHODS: We conducted an intervention study of indoor CO(2) levels and sick leave among hourly office workers employed by a large corporation. Outdoor air supply rates were adjusted periodically to increase the range of CO(2) concentrations. We recorded indoor CO(2) concentrations every 10 minutes and calculated a CO(2) concentration differential as a measure of outdoor air supply per person by subtracting the 1–3 a.m. average CO(2) concentration from the same-day 9 a.m. – 5 a.m. average concentration. The metric of CO(2) differential was used as a surrogate for the concentration of exhaled breath and for potential exposure to human source airborne respiratory pathogens. RESULTS: The weekly mean, workday, CO(2) concentration differential ranged from 37 to 250 ppm with a peak CO(2) concentration above background of 312 ppm as compared with the American Society of Heating, Refrigeration and Air-conditioning Engineers (ASHRAE) recommended maximum differential of 700 ppm. We determined the frequency of sick leave among 294 hourly workers scheduled to work approximately 49,804.2 days in the study areas using company records. We found no association between sick leave and CO(2) differential CONCLUSIONS: The CO(2) differential was in the range of very low values, as compared with the ASHRAE recommended maximum differential of 700 ppm. Although no effect was found, this study was unable to test whether higher CO(2) differentials may be associated with increased sick leave

Deiminated proteins and extracellular vesicles - novel serum biomarkers in whales and Orca

Peptidylarginine deiminases (PADs) are a family of phylogenetically conserved calcium-dependent enzymes which cause post-translational protein deimination. This can result in neoepitope generation, affect gene regulation and allow for protein moonlighting via functional and structural changes in target proteins. Extracellular vesicles (EVs) carry cargo proteins and genetic material and are released from cells as part of cellular communication. EVs are found in most body fluids where they can be useful biomarkers for assessment of health status. Here, serum-derived EVs were profiled, and post-translationally deiminated proteins and EV-related microRNAs are described in 5 ceataceans: minke whale, fin whale, humpback whale, Cuvier's beaked whale and orca. EV-serum profiles were assessed by transmission electron microscopy and nanoparticle tracking analysis. EV profiles varied between the 5 species and were identified to contain deiminated proteins and selected key inflammatory and metabolic microRNAs. A range of proteins, critical for immune responses and metabolism were identified to be deiminated in cetacean sera, with some shared KEGG pathways of deiminated proteins relating to immunity and physiology, while some KEGG pathways were species-specific. This is the first study to characterise and profile EVs and to report deiminated proteins and putative effects of protein-protein interaction networks via such post-translationald deimination in cetaceans, revealing key immune and metabolic factors to undergo this post-translational modification. Deiminated proteins and EVs profiles may possibly be developed as new biomarkers for assessing health status of sea mammals

Economic Experiments on Impulsive Urges, Control, and Irrationality

One of the standard assumptions underlying microeconomic theory is that more opportunities from which to choose cannot be a bad thing. Indeed, it is logical from a welfare perspective and a common sense perspective that things like more employment opportunities, including the social mobility that goes along with it, allows a person to realize a higher level of life satisfaction in multiple realms. Logically this freedom to choose should extend to the decision situation, in that a person should not seek to restrict the type of environment she makes her decisions in. This thesis contains studies in which decision environments have potential negative effects on the decision-maker’s welfare. We believe that if the decision maker were to be made aware of the type of effect the environment had on her decision, she would seek to restrict her environment, in other words the way information is transmitted to her.More generally, the thesis looks at different types of control. All studies have to do with control, whether it be internal control, such as dealing with one’s own temptations, or external control, such as an irrational aversion to ceding another person control over your own payoff (for example, allowsing someone else to be in the driver seat despite equal abilities, or an unwillingness to let a computer determine one’s own lotto ticket numbers). It looks at human decision making through the lens of dual processing models, specifically the interplay between an impulsive, fast, and biased decision-making system; and a slow, deliberative, rational one (2004). Much behavioral research is pointing to the importance of understanding these two motivations in everything from exercise patterns to reciprocity in social interactions (DellaVigna & Malmendier (2006), Knoch, et al., (2006)).This thesis is divided into four chapters. The first three chapters concern behavioral biases and inconsistencies brought to light by psychologists and behavioral scientists. The fourth chapter concerns the processing of conflicting motivation in social decision making. The first two chapters concern intertemporal decision making. Chapters 1, 2, and 4 are joint work with Urs Fischbacher.Chapter 1 (Projection Bias: The Price for Food Craving) is about biases in how people predict their future preferences. Most decisions people make involve consequences for the future, and as a result the decision maker must make an estimate about what her preferences will be at that time. Of course these predictions are just that, an estimate, and are subject to error. They are also subject to biases. Projection bias (Loewenstein, O'Donoghue, & Rabin, 2003) is the tendency for predictions about preferences in a different “state” from the one at the moment of deciding are biased toward the one a person is in at the moment of deciding. For instance, Read & van Leeuwen (1998) show that people who are hungry when making a decision are more likely to choose an unhealthy snack to be received at a future date than people who are not hungry when making the decision. Indeed, if a person expects to be hungry in the future it makes sense to pick the more calorie rich food item, and people do. However, current levels of hunger should have no effect, but there is a large impact. Of those who are hungry when making their decision, 78% (56%) choose the unhealthy snack when they predict they will be hungry (satiated) at the time of receipt, whereas for those who are satiated when decided, only 42% (26%) choose the unhealthy, calorie-rich snack.Our study also deals with projection bias under hungry and sated states. We use an exogenous and randomly assigned treatment variable to manipulate hunger levels of our subjects, whereas past studies have not. In our experiment, subjects participate in a Vickrey auction for high quality chocolates to be received on a later day, in which it is optimal for a subject to bid her true willingness to pay for a good. We are therefore not only able to show the existence of projection bias, we also show its effect on willingness to pay for products. Projection bias in the marketplace affects consumption decisions, and therefore lifetime patterns of consumption, saving, and overall well-being. It is also a potential source of gain for firms, and for these reasons understanding how projection bias translates into willingness to pay is important. We show that hungry subjects are willing to pay 58% higher prices for a small box of chocolates than sated subjects.Chapter 2 (Battling Impulses: Intertemporal Choice in the Short Term) contains three experiments about self-control. Many studies look at impatience by giving subjects a series of decisions between an early, small payoff and a later, larger payoff (delay discounting tasks). These types of studies generally go further to estimate the implied discount rates of subjects’ decisions. Most studies (with a few exceptions) use monetary rewards as a payoff medium, and time spans of the tradeoffs are quite large, on the order of months or years. Using monetary rewards to study time preferences involves problems, mainly because money is not a primary reward; rather it is an opportunity set from which people can obtain a real reward. We are interested in this study in very short term impatience. Indeed, we think that short term impatience is very important to understand, as most temptation occurs when the prospect of a reward is imminent. This makes the use of monetary rewards even less appropriate for our study. We therefore introduce the paradigm of computer games as a medium of reward. Past studies have used food; we viewed this as problematic as we expect it to violate the “more is not worse” concept. We chose our computer game to be tempting and enjoyable, and contrasted it with an annoying task. We did this, so that even if subjects did not want expressly to play the game (which they were not forced to play), they would still desire to avoid the annoying task. Our treatment variable is intended to manipulate the degree to which impulsive motivations are given priority. In the less impulse-friendly environment, subjects make decisions regarding the game before they start the experiment, so before they are actually involved in the game or the task. In the more impulsive environment, they make their decisions while doing the game or task.We link behavior in our “temptation tasks” to scores on the Barratt Impulsiveness Scale (BIS), and in experiment 3 of the series we show that behavior is additionally linked to the delay discounting task, using Amazon.de gift certificates as a reward medium. We find that scores on the BIS have more predictive power in the impulsive condition. Furthermore, we find with the delay discounting task that subjects are “present-oriented”; that is have declining discount rates.Chapter 3 (Handing Over the Reins: On the Social Nature of the Illusion of Control) concerns the “Illusion of Control” brought to light by Ellen Langer (1975). The illusion of control appears in decisions involving risk. Risky decisions in real life not only involve risk preferences, but also skill. For example, skiing is a risky activity, but the more skill a person has, the lower the probability of an accident (holding choice of slope difficulty constant). In this situation, the amount of risk a person takes depends in part on her assessment of her own skill level. Ellen Langer argues that people conflate the skill with the risk elements, and even when they are given control over elements of a task that have no influence on the risk involved, act as if they have been given (partial) control over the lottery. This leads people to potentially take more risk in situations in which they have a feeling of control.Recent work by economists has challenged this notion, and found conflicting results over whether the bias exists. Past studies have generally compared giving illusory control to the decision maker versus giving it to another person. In this paper, I put forth the proposition that this comparison may lead to many different conclusions about whether there is an illusion of control if there is heterogeneity in subjects’ perceptions of their own skill level versus that of another person. I therefore conduct an experiment which makes it possible to observe whether there is heterogeneity in the type of illusion subjects have, and to then categorize them according to this characteristic. I also link their observed illusion of control to scores on the Magical Ideation Scale, which has been shown to be positively related to illusion of control biases (Brugger & Graves, 1997). I find in my study what initially looks like an illusion of control. However, I argue that it is actually the result of randomization. I also observe a link between scores on the Magical Ideation Scale and the amount of variation in individual answers, which I also will argue is the result of randomization, coupled with the unusual distribution of Magical Ideation scores.Chapter 4 (Social Decision-Making Processes) looks at the processing of different types of conflict in social decision making through observing reaction times. We look at ego conflict (conflict between selfish and social motives) and social conflict (conflict between different social motivating factors). We use traditional (1st party) dictator games, where a decision maker decides over distributions of money for herself and another person, as well as 3rd party dictator games in which a decision maker decides over distributions for two other people with no consequences for her own payoff. We record reaction times as a way of measuring the conflict in a decision and as a way to assess the automaticity or controlled nature of selfish and social motivations. Rubinstein (2007) showed that reaction times could be used as a measurement of conflict when making a decision, and that lower conflict results in quick responses and higher conflict in faster responses. Additionally, automatic processes are thought to be fast and cheap, whereas controlled ones are slow and expensive; therefore we will be able to use reaction times to examine this idea. In our context, the 1st party decisions contain more conflict than the 3rd party conditions, simply because they contain a selfish motivation. With the 3rd party condition, we can assess the individual’s personal norm; that is her attitude about what is a fair way to allocate between two people independent of any selfish motivation. Past studies have shown that selfish decisions are made more quickly than decisions in favor of another person. We introduce the 3rd party condition to assess whether it is the selfish aspect of the decision that results in faster reaction times for selfish decisions, or another, previously undetected property of the decision.We find that an increase in social conflict (that is, conflict between social motivating factors) results in increased reaction times. We further found that though selfish decisions are made faster, this is not the result of selfish motivation, but of other aspects of the decision. We also find that the personal norm is not well characterized according to our three identified types of social motivation (efficiency, maximin preferences, and absolute inequality aversion). The personal norm predicts increases in reaction times better than ego conflict with any particular social property, showing that the personal norm captures individual heterogeneity in values

Hard Real-Time Streaming of Large Data Objects with Overlapping Backward Error Correction

Despite expectations in roadmaps, the reliable V2X exchange of large data objects under age constraints remains an open challenge. Earlier work proposed a protocol that improved reliability by an application-level Backward Error Correction (BEC) mechanism that operates on data objects rather than packets. In this paper, we extend the protocol to overlapping data object transmission and investigate how far we can increase reliability by relaxing the object transmission deadline to realistic latency requirements as found in the literature. The extended protocol can be used for reliable coupling of nodes and wired network segments in the automotive and industrial domain that exchange large data. As an example, a camera stream transmission from truck platooning is used that aims at improving effectiveness of logistics as part of a large-scale industrial process. We present an analytical model for the extended error correction protocol and evaluate the reliability improvement with an OMNeT++ simulation model that incorporates a state-of-the-art burst error model. For realistic application deadlines, the results show a significant reliability improvement especially for burst errors, at constant protocol overhead