Aerospace medicine and biology: A continuing bibliography with indexes (supplement 324)

This bibliography lists 200 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during May, 1989. Subject coverage includes: aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life, and flight crew behavior and performance

Automated robot‐assisted surgical skill evaluation: Predictive analytics approach

BackgroundSurgical skill assessment has predominantly been a subjective task. Recently, technological advances such as robot‐assisted surgery have created great opportunities for objective surgical evaluation. In this paper, we introduce a predictive framework for objective skill assessment based on movement trajectory data. Our aim is to build a classification framework to automatically evaluate the performance of surgeons with different levels of expertise.MethodsEight global movement features are extracted from movement trajectory data captured by a da Vinci robot for surgeons with two levels of expertise – novice and expert. Three classification methods – k‐nearest neighbours, logistic regression and support vector machines – are applied.ResultsThe result shows that the proposed framework can classify surgeons’ expertise as novice or expert with an accuracy of 82.3% for knot tying and 89.9% for a suturing task.ConclusionThis study demonstrates and evaluates the ability of machine learning methods to automatically classify expert and novice surgeons using global movement features.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141457/1/rcs1850.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/141457/2/rcs1850_am.pd

Üner Tan Syndrome: Review and Emergence of Human Quadrupedalism in Self-Organization,\ud Attractors and Evolutionary Perspectives\ud

The first man reported in the world literature exhibiting habitual quadrupedal locomotion was discovered by a British traveler and writer on the famous Baghdat road near Havsa/Samsun on the middle Black-Sea coast of Turkey (Childs, 1917). Interestingly, no single case with human quadrupedalism was reported in the scientific literature after Child's first description in 1917 until the first report on the Uner Tan syndrome (UTS: quadrupedalism, mental retardation, and impaired speech or no speech)in 2005 (Tan, 2005, 2006). Between 2005 and 2010, 10 families exhibiting the syndrome were discovered in Turkey with 33 cases: 14 women (42.4%) and 19 men (57.6%). Including a few cases from other countries, there were 25 men (64.1%)and 14 women (35.9%). The number of men significantly exceeded the number of women (p < .05). Genetics alone did not seem to be informative for the origins of many syndromes, including the Uner Tan syndrome. From the viewpoint of dynamical systems theory, there may not be a single factor including the neural and/or genetic codes that predetermines the emergence of the human quadrupedalism.Rather, it may involve a self-organization process, consisting of many decentralized and local interactions among neuronal, genetic, and environmental subsystems. The most remarkable characteristic of the UTS, the diagonal-sequence quadrupedalism is well developed in primates. The evolutionarily advantage of this gait is not known. However, there seems to be an evolutionarily advantage of this type of locomotion for primate evolution, with regard to the emergence of complex neural circuits with related highly complex structures. Namely, only primates with diagonal-sequence quadrupedal locomotion followed an evolution favoring larger brains, highly developed cognitive abilities with hand skills, and language, with erect posture and bipedal locomotion, creating the unity of human being. It was suggested that UTS may be considered a further example for Darwinian diseases, which may be associated with an evolutionary understanding of the disorders using evolutionary principles, such as the natural selection. On the other hand, the human quadrupedalism was proposed to be a phenotypic example of evolution of reverse, i.e., the reacquisition by derived populations of the same character states as those of ancestor populations. It was also suggested that the emergence of the human quadrupedalism may be related to self-organizing processes occurring in complex systems, which select or attract one preferred behavioral state or locomotor trait out of many possible attractor states. Concerning the locomotor patterns, the dynamical systems in brain and body of the developing child may prefer some kind of locomotion, according to interactions of the internal components and the environmental conditions, without a direct role of any causative factor(s), such as genetic or neural codes, consistent with the concept of self-organization, suggesting no single element may have a causal priority

Aerospace medicine and biology: A continuing bibliography with indexes (supplement 325)

This bibliography lists 192 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during June, 1989. Subject coverage includes: aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life, and flight crew behavior and performance

Effects of sleep deprivation on postural control

Sleep is an essential biological requirement for the human organism to regulate its physiological, physical, cognitive, psychological and emotional resources, according to its necessities, allowing the functionality to carry out daily activities successfully. Evidence claims that sleep deprivation has a negative impact on physical performance, motor development and quality of life. One of the components that reflects motor performance is postural control. Sleep deprivation decreases considerably the capacity of stabilizing the neuromuscular system and adapting to environmental constraints, leading to a greater propensity to injuries and falls. This study aims to investigate the effects of a 24-hour sleep deprivation on postural control. Seventeen healthy participants (age 23.88±2.42 years, height 1.75±0.06 m, weight 71.80±7.97 kg, body mass index 23.30±1.80 kg/m2) visited the laboratory on two occasions: pre and post 24 hours of sleep deprivation. In both sessions, participants performed the postural control assessment, using the posturography technique. The protocol consisted on stabilizing the body, standing on both legs over a platform, for two minutes, while remaining quiet. The evaluation was performed twice, under two conditions: with eyes opened, and with eyes closed. Linear parameters of the center of pressure data were analyzed. Non-linear parameters of variability in the regularity of postural control were also determined through the sample entropy metric. Paired samples t-tests or a Wilcoxon Signed-rank tests were performed to test the effect of sleep deprivation on all dependent variables. Nearly all linear parameters showed an increase after sleep deprivation (excluding range in the anterior-posterior direction in eyes opened condition, which was maintained), while sample entropy decreased. Our findings show that 24 hours of sleep deprivation negatively affects postural control. This study confirmed the observations of previous studies using linear variables and provided a new contribution regarding the effects of a 24-hour sleep deprivation on the complexity of postural control and motor performance. The measure of entropy reflects the adaptability of motor control and acts as an indirect index of the functional capacity of the human neuromuscular system. Accordingly, in a state of sleep deprivation, psychomotor, cognitive and adaptability capacities are reduced, suggesting that there is a greater probability of compromising the neuromuscular system and, consequently, a greater exposure to injuries and falls.O sono é um requisito biológico essencial para manter o organismo humano a regular o equilíbrio a nível fisiológico, físico, cognitivo, psicológico e emocional, de forma adequada e de acordo com as suas necessidades, permitindo restabelecer a sua funcionalidade para realizar as atividades diárias e garantir o seu bem-estar. Existe evidência de que a privação do sono tem um impacto negativo no desenvolvimento motor e na qualidade de vida. Uma das componentes que reflete o desempenho motor é o controlo postural. As situações de privação de sono aumentam consideravelmente as dificuldades na capacidade de estabilização do sistema neuromuscular e em adaptá-lo a constrangimentos do ambiente, tendendo a aumentar o risco de lesões e quedas. Desta forma, este estudo tem como objetivo investigar o efeito de 24 horas de privação do sono no controlo postural. Dezassete sujeitos saudáveis (idade 23.88±2.42 anos, altura 1.75±0.06 m, massa corporal 71.80±7.97 kg, índice de massa corporal 23.30±1.80 kg/m2) visitaram o laboratório em duas ocasiões; pré e pós 24 horas de privação do sono. Nas duas sessões, os participantes realizaram a avaliação do controlo postural a partir da técnica de posturografia. O protocolo consistiu na estabilização da postura em pé e bipedal, durante dois minutos. A avaliação realizou-se duas vezes, sob duas condições: olhos abertos e olhos fechados. Foram analisados os parâmetros lineares que caracterizam o equilíbrio postural, a partir dos dados do centro de pressão. Foram também determinados parâmetros não lineares de variação da regularidade do controlo postural, através da métrica da entropia amostral, na direção ântero-posterior (SampEn AP) e médio-lateral (SampEn ML). Foram efetuados testes t para amostras emparelhadas e os testes de Wilcoxon para testar o efeito da privação do sono de todas as variáveis dependentes. Em quase todos os parâmetros lineares foi observado um aumento depois da privação de sono (com exceção da amplitude na direção ântero-posterior na condição de olhos abertos, que se manteve), enquanto a entropia amostral diminuiu. Os resultados indicam que a privação de 24 horas de sono afeta negativamente o controlo postural. Este estudo confirmou as observações de estudos anteriores a partir de variáveis lineares e ainda forneceu um novo contributo em relação aos efeitos da privação do sono na complexidade do controlo postural e do controlo motor. A medida reflete a adaptabilidade do controlo motor e atua como uma medida indireta da capacidade funcional do sistema neuromuscular humano. Um estado de 24 horas de privação de sono contribuiu para a redução das capacidades psicomotoras, cognitivas e a adaptabilidade aos constrangimentos, sugerindo-se que existe maior probabilidade em comprometer o sistema neuromuscular e, consequente, maior exposição para ocorrência de lesões e quedas

Computational Modeling Approaches For Task Analysis In Robotic-Assisted Surgery

Surgery is continuously subject to technological innovations including the introduction of robotic surgical devices. The ultimate goal is to program the surgical robot to perform certain difficult or complex surgical tasks in an autonomous manner. The feasibility of current robotic surgery systems to record quantitative motion and video data motivates developing descriptive mathematical models to recognize, classify and analyze surgical tasks. Recent advances in machine learning research for uncovering concealed patterns in huge data sets, like kinematic and video data, offer a possibility to better understand surgical procedures from a system point of view. This dissertation focuses on bridging the gap between these two lines of the research by developing computational models for task analysis in robotic-assisted surgery. The key step for advance study in robotic-assisted surgery and autonomous skill assessment is to develop techniques that are capable of recognizing fundamental surgical tasks intelligently. Surgical tasks and at a more granular level, surgical gestures, need to be quantified to make them amenable for further study. To answer to this query, we introduce a new framework, namely DTW-kNN, to recognize and classify three important surgical tasks including suturing, needle passing and knot tying based on kinematic data captured using da Vinci robotic surgery system. Our proposed method needs minimum preprocessing that results in simple, straightforward and accurate framework which can be applied for any autonomous control system. We also propose an unsupervised gesture segmentation and recognition (UGSR) method which has the ability to automatically segment and recognize temporal sequence of gestures in RMIS task. We also extent our model by applying soft boundary segmentation (Soft-UGSR) to address some of the challenges that exist in the surgical motion segmentation. The proposed algorithm can effectively model gradual transitions between surgical activities. Additionally, surgical training is undergoing a paradigm shift with more emphasis on the development of technical skills earlier in training. Thus metrics for the skills, especially objective metrics, become crucial. One field of surgery where such techniques can be developed is robotic surgery, as here all movements are already digitalized and therefore easily susceptible to analysis. Robotic surgery requires surgeons to perform a much longer and difficult training process which create numerous new challenges for surgical training. Hence, a new method of surgical skill assessment is required to ensure that surgeons have adequate skill level to be allowed to operate freely on patients. Among many possible approaches, those that provide noninvasive monitoring of expert surgeon and have the ability to automatically evaluate surgeon\u27s skill are of increased interest. Therefore, in this dissertation we develop a predictive framework for surgical skill assessment to automatically evaluate performance of surgeon in RMIS. Our classification framework is based on the Global Movement Features (GMFs) which extracted from kinematic movement data. The proposed method addresses some of the limitations in previous work and gives more insight about underlying patterns of surgical skill levels

Brain enhancement through cognitive training: A new insight from brain connectome

Owing to the recent advances in neurotechnology and the progress in understanding of brain cognitive functions, improvements of cognitive performance or acceleration of learning process with brain enhancement systems is not out of our reach anymore, on the contrary, it is a tangible target of contemporary research. Although a variety of approaches have been proposed, we will mainly focus on cognitive training interventions, in which learners repeatedly perform cognitive tasks to improve their cognitive abilities. In this review article, we propose that the learning process during the cognitive training can be facilitated by an assistive system monitoring cognitive workloads using electroencephalography (EEG) biomarkers, and the brain connectome approach can provide additional valuable biomarkers for facilitating leaners' learning processes. For the purpose, we will introduce studies on the cognitive training interventions, EEG biomarkers for cognitive workload, and human brain connectome. As cognitive overload and mental fatigue would reduce or even eliminate gains of cognitive training interventions, a real-time monitoring of cognitive workload can facilitate the learning process by flexibly adjusting difficulty levels of the training task. Moreover, cognitive training interventions should have effects on brain sub-networks, not on a single brain region, and graph theoretical network metrics quantifying topological architecture of the brain network can differentiate with respect to individual cognitive states as well as to different individuals' cognitive abilities, suggesting that the connectome is a valuable approach for tracking the learning progress. Although only a few studies have exploited the connectome approach for studying alterations of the brain network induced by cognitive training interventions so far, we believe that it would be a useful technique for capturing improvements of cognitive function

Neurobehavioral changes in response to long-duration bed rest

As space-faring nations across the globe are fueling a new race of human space exploration that goes well beyond the Moon, national agencies and private entities across the globe have accelerated the research and development that will promote the safety and success of such missions. Prolonged body unloading and reduced physical activity levels associated with space travel could adversely affect brain and behavior. Long-duration bed rest in –6° head-down tilt (>1 month) is an established spaceflight analog on Earth to simulate the physiological and psychological adaptations of prolonged inactivity and headward fluid shift during space travel. The present work investigated the effects of long-duration bed rest on brain function and cognitive performance. In a series of five studies combining behavioral, electrocortical and magnetic resonance imaging data it was shown that bed rest can induce significant functional brain changes and cognitive impairments including emotion processing, memory formation, and selective attention, and that these effects may not recover quickly. Structured physical activity programs superimposed to bed rest were found to mitigate cognitive impairments. The benefits of antioxidant supplementation and artificial gravity or their combination with exercise remain to be determined. Some caution is warranted when behavioral data are collected in different body positions, i.e., seated vs. head-down tilt, because the neurophysiological reactions associated with postural changes may mask the effects attributed to physical inactivity. Future work in this field should be characterized by an interdisciplinary approach, integrating multimodal brain imaging, psychological and behavioral, neurovestibular, cardiovascular, biochemical, and circadian data. Such an approach could promote a holistic understanding of intellectual frameworks that together exceed individual disciplinary perspectives. The knowledge from such approaches could go beyond their application to spaceflight. It can translate to the prevention and treatment of various clinical conditions associated with cognitive impairments, and for which reduced physical activity levels are a critical risk factor

New insights into the behavioral structure of Pikler educators : An application of T-pattern detection and analysis with THEME

The recent generalization of early childhood schooling has given rise to a need for the development of rigorous, specific training programs aimed at early education professionals (0-3 years of age). This work emanates from the unique nature of Pikler-Lóczy education as a reference for early childhood education centers, and its expertise in providing quality care in an everyday classroom situation. The aim of the study is to use T-pattern detection and analysis, within the framework of observational methodology, to identify relevant aspects of the choreography followed by Pikler educators during breakfast, and thus provide substantial material with a view to creating a training plan. Two expert educators in Pikler-Lóczy education were directly and systematically observed in their own classrooms, following a nomothetic, follow-up and multidimensional design. The observation instrument underwent a molarization process so that the detected elements would be more significant and understandable for novice educators. Using THEME, the invariant aspects of the educators' behavior were analyzed. The significance level for the critical interval was the THEME default (α = 0.005). The results show: on the one hand, changes expected in T-patterns in accordance with the observation instrument molarity; and on the other hand, stability in terms of the comparison between the two educators. These results help us to identify the complex structure of the breakfast choreography, and how educators establish interaction with children. In addition to specific issues pertaining to Pikler-Lóczy education, the conclusions highlight the advantages of using T-pattern analysis within the framework of observational methodology, in order to dissect a mealtime routine in its natural context, and explain components of early childhood education intervention that satisfy basic childhood needs. This constitutes a starting point from which to generate instructive material for the training of professionals working in early education