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Adequate oxygen supply is essential for the human brain to meet its high energy demands. Therefore, elaborate molecular and systemic mechanism are in place to enable adaptation to low oxygen availability. Anxiety and depressive disorders are characterized by alterations in brain oxygen metabolism and of its components, such as mitochondria or hypoxia inducible factor (HIF)-pathways. Conversely, sensitivity and tolerance to hypoxia may depend on parameters of mental stress and the severity of anxiety and depressive disorders. Here we discuss relevant mechanisms of adaptations to hypoxia, as well as their involvement in mental stress and the etiopathogenesis of anxiety and depressive disorders. We suggest that mechanisms of adaptations to hypoxia (including metabolic responses, inflammation, and the activation of chemosensitive brain regions) modulate and are modulated by stress-related pathways and associated psychiatric diseases. While severe chronic hypoxia or dysfunctional hypoxia adaptations can contribute to the pathogenesis of anxiety and depressive disorders, harnessing controlled responses to hypoxia to increase cellular and psychological resilience emerges as a novel treatment strategy for these diseases.

Natural scenes are typically highly heterogeneous, making it difficult to assess camouflage effectiveness for moving objects since their local contrast varies with their momentary position. Camouflage performance is usually assessed through visual search and detection experiments involving human observers. However, such studies are time-consuming and expensive since they involve many observers and repetitions. Here, we show that a (state-of-the-art) convolutional neural network (YOLO) can be applied to measure the camouflage effectiveness of stationary and moving persons in a natural scene. The network is trained on human observer data. For each detection, it also provides the probability that the detected object is correctly classified as a person, which is directly related to camouflage effectiveness: more effective camouflage yields lower classification probabilities. By plotting the classification probability as a function of a person’s position in the scene, a ‘camouflage efficiency heatmap’ is obtained, that reflects the variation of camouflage effectiveness over the scene. Such a heatmap can for instance be used to determine locations in a scene where the person is most effectively camouflaged. Also, YOLO can be applied dynamically during a scene traversal, providing real-time feedback on a person’s detectability. We compared the YOLO-predicted classification probability for a soldier in camouflage clothing moving through a rural scene to human performance. Camouflage effectiveness predicted by YOLO agrees closely with human observer assessment. Thus, YOLO appears an efficient tool for the assessment of camouflage of static as well as dynamic objects.

In order to assess camouflage and the role of movement under widely ranging (lighting, weather, background) conditions simulation techniques are highly useful. However, sufficient level of fidelity of the simulated scenes is required to draw conclusions. Here, live recordings were obtained of moving soldiers and simulations of similar scenes were created. To assess the fidelity of the simulation a search experiment was carried out in which performance of recorded and simulated scenes was compared. Several movies of bushland environments were shown (recorded as well as simulated scenes) and participants were instructed to find the moving target as rapidly as possible within a time limit. In another experiment, visual conspicuity of the targets was measured. For static targets it is well known that the conspicuity (i.e., the maximum distance to detect a target in visual periphery) is a valid measure for camouflage efficiency as it predicts visual search performance. In the present study, we investigate whether conspicuity also predicts search performance for moving targets. In the conspicuity task, participants saw a short (560 ms) part of the movies used for the search experiments. This movie was presented in a loop such that the target moved forward, backward, forward, etcetera. Conspicuity was determined as follows: a participant starts by fixating a location in the scene far away from the target so that he/she is not able to detect it. Next, the participant fixates progressively closer to the target location until the target can just be detected in peripheral vision; at this point the distance to the target is recorded. As with static stimuli, we show that visual conspicuity predicts search performance. This suggests that conspicuity may be used as a means to establish whether simulated scenes show sufficiently fidelity to be used for camouflage assessment (and the effect of motion).

Targets that are well camouflaged under static conditions are often easily detected as soon as they start moving. We investigated and evaluated ways to design camouflage that dynamically adapts to the background and conceals the target while taking the variation in potential viewing directions into account. In a human observer experiment recorded imagery was used to simulate moving (either walking or running) and static soldiers, equipped with different types of camouflage patterns and viewed from different directions. Participants were instructed to search for the soldier and to make a speeded response as soon as they detected the soldier. Mean correct search times and mean detection probability were compared between soldiers in standard (Netherlands) Woodland uniform, in static camouflage (adapted to the local background) and in dynamically adapting camouflage. We investigated the effects of background type and variability on detection performance by varying the soldiers’ environment (like bushland, and urban). In general, performance was worse for dynamic soldiers compared to static soldiers, confirming the notion that motion breaks camouflage. Furthermore, camouflage performance of the static adaptive camouflage condition was generally much better than for the standard Woodland camouflage. Also, camouflage performance was found to depend on the background. When moving across a highly variable (heterogenous) background, dynamic camouflage turned out to be especially beneficial (i.e., performance was better in a bush environment than in an urban environment). Interestingly, our dynamic camouflage design was outperformed a method which simply displays the ‘exact’ background on the camouflage suit, since it is better capable of taking the variability in viewing directions into account. By combining new adaptive camouflage technologies with dynamic adaptive camouflage designs such as the one presented here it may become possible to prevent detection of moving targets in the (near) future.

Poster Session I. The sense of time continuity appears to be disturbed in pathologies like schizophrenia, associated with a disruption of the sense of self, and of the feeling of being immersed in the world. Prediction mechanisms have been proposed to be involved in the sense of time continuity by helping to relate discontinuous events, and our previous studies have suggested that these mechanisms may occur even at the millisecond level. Such mechanisms would be involved in our ability to interact with the outer world, by helping to follow events accurately in both space and time. We explored prediction mechanisms and attention shifts based on recently experienced sequences of visual information (sequential effects). Methods. 26 patients with schizophrenia and 20 matched controls were included in asynchrony discrimination tasks, and assessments of minimal self disorders with the EASE. On each trial, two stimuli are displayed with varying stimulus onset asynchronies (SOA). Subjects decide whether the stimuli are simultaneous or asynchronous and give manual responses. Sequential effects were explored further in several groups of 15 healthy participants. Results. The main finding in controls is a strong accuracy advantage for different- as compared to same-order trials, but only when trial t is with an SOA slightly larger than trial t-1 (advantage of 16% in accuracy), or equivalent (advantage of 10% in accuracy). An advantage for same-vs. different-order trials is observed only when the SOA on the previous trial is large and visible. In patients, there is no advantage for same-order trials. There is a clear advantage for different-order trials (advantage of 16% in accuracy), but this effect disappears, contrary to controls, when SOAs are equivalent on successive trials (1% difference in accuracy). The impairment in the trial-to-trial effects in patients correlates with minimal self disorders (the EASE). Discussion. Further investigations in healthy participants suggest that the sequential effects can be explained in terms of prediction of stimulus sequences from trial to trial, which are accompanied by an attention shift. The first stimulus triggers the onset of the sequence, and attention is then covertly shifted in space and time according to the previous trial, in order to attend to the second stimulus. This explains the advantage for different-order trials: when order is reversed on the present trial, attention ends up in the location of the first stimulus of the present sequence. This first stimulus is perceived as isolated on the screen if the second stimulus occurs later than on the previous trial, thus facilitating the detection of an asynchrony. The asynchrony is then obvious, explaining the large amplitude of the effect. The fact that the effect extends to the condition in which SOAs are equivalent on successive trials suggests that participants shift their attention in advance, as if anticipating the location of the second stimulus. This is impaired in patients, who replay sequences of events, but do not anticipate the successive events flexibly. This would impair their immersion in the world, where events rarely happen twice at the same time exactly.

This paper is part of a continuing effort to investigate constraining and enabling effects of institutional logics on entrepreneurship in the European space sector. The goal is mapping rules, regulations, ideas and cultural standards hindering or stimulating entrepreneurship in ESA Member States in general, and in particular on the subject of this paper, the Czech Republic. Interviews with various Czech space actors were conducted, analyzed and related to archival data on the Czech space sector. On an agency level, two logics are identified, perceived as being either supporting or constraining by entrepreneurs and small companies: the country cooperation logic and the European institution logic. On a national level, the new sector logic, the prime contractor and a product logic are identified as driving and constraining forces for Czech entrepreneurs. The new sector logic entails challenges of entrepreneurs and SMEs arising from new or inadequate regulation, conservative government funding decisions and a misalignment of national priorities for space activities with the expectations of Czech space actors. The prime contractor logic encompasses entrepreneurial activities concerning building, growing and changing relations to traditional, large ESA contractors that govern entrepreneurial decisions on a national level. The product logic describes the constraints and drivers imposed on entrepreneurs by the quality requirements of space products, as well as the competition of new products with ESA quality standards.

The extinction of conditioned fear responses entrains the formation of safe new memories to decrease those behavioral responses. The knowledge in neuronal mechanisms of extinction is fundamental in the treatment of anxiety and fear disorders. Interestingly, the use of pharmacological compounds that reduce anxiety and fear has been shown as a potent co-adjuvant in extinction therapy. However, the efficiency and mechanisms by which pharmacological compounds promote extinction of fear memories remains still largely unknown and would benefit from a validation based on functional neuronal circuits, and the neurotransmitters that modulate them. From this perspective, oxytocin receptor signaling, which has been shown in cortical and limbic areas to modulate numerous functions (Eliava et al. Neuron 89(6):1291-1304, 2016), among them fear and anxiety circuits, and to enhance the salience of social stimuli (Stoop Neuron 76(1):142-59, 2012), may offer an interesting perspective. Experiments in animals and humans suggest that oxytocin could be a promising pharmacological agent at adjusting memory consolidation to boost fear extinction. Additionally, it is possible that long-term changes in endogenous oxytocin signaling can also play a role in reducing expression of fear at different brain targets. In this review, we summarize the effects reported for oxytocin in cortico-limbic circuits and on fear behavior that are of relevance for the modulation and potential extinction of fear memories.

The REvivED water project aims to contribute to overcoming the drinking water challenge through desalination technology. The goal is to produce safe and affordable drinking water with a significantly reduced energy consumption compared to the current state-of-the-art technology. The overall project comprises several systems and applications with twelve pilots in total, ranging from Electrodialysis (ED) small systems for brackish water desalination to larger scale hybrid (RED/ED-RO) systems for sea water desalination. Specific attention is devoted to develop energy efficient and robust brackish water desalination systems for application in developing countries. To reduce the energy consumption of the desalination process, several design parameters have been optimized, e.g., membranes and spacers characteristics, stack configurations, flow path length. To assure the system robustness, several concepts have been investigated, including pre-treatment options, capacitive electrodes, one pass flow as well as gravity driven flow. Intensive modelling and experimental validation are being carried out for the process and system design. The first brackish water desalination results demonstrate that up to a conductivity of ~4.000 µs/cm the project energy consumption target of 0.4 kWh/m3 can be achieved.

This study builds a grounded model of how careers shape entrepreneurs’ preferences for causal and effectual decision logics when starting new ventures. Using both verbal protocol analysis and interviews, we adopt a qualitative research approach to induct career management practices germane to entrepreneurial decision making. Based on our empirical findings, we develop a model conceptualizing how configurations of career management practices, reflecting different emphases on career planning and career investment, are linked to entrepreneurial decision making through the imprint that they leave on one’s view of the future, generating a tendency toward predictive and/or creative control. These findings extend effectuation theorizing by reformulating one of its most pervasive assumptions and showing how careers produce distinct pathways to entrepreneurial thinking, even prior to entrepreneurial entry.

In manual choice reaction time (RT) tasks, people respond faster to a visual target stimulus when it is accompanied by a task-irrelevant tone than when it is presented alone. This intersensory facilitation effect is often attributed to multisensory integration, but here we show it to be a reflection of temporal preparation. According to this view, the more rapidly processed tone serves as a warning signal (S1), which initiates preparation for the more sluggish visual target (S2). To test this view, we varied the delay between S1 and S2 in conjunction with the modality of S1 (auditory or visual). For brief delays, responses to S2 were faster when S1 was auditory than when it was visual. Crucially, however, this intersensory facilitation effect disappeared after correction for the difference in S1-detection time, equating the effective preparation period. This shows that sound speeds response to a visual target only through preparation. © 2013 American Psychological Association.

In the present study, observers viewed displays in which two equally salient color singletons were simultaneously present. Before each trial, observers received a word cue (e. g., the word red, or green) or a symbolic cue (a circle colored red or green) telling them which color singleton to select on the upcoming trial. Even though many theories of visual search predict that observers should be able to selectively attend the target color singleton, the results of the present study show that observers could not select the target singleton without interference from the irrelevant color singleton. The results indicate that the irrelevant color singleton captured attention. Only when the color of the target singleton remained the same from one trial to the next was selection perfect-an effect that is thought to be the result of passive automatic intertrial priming. The results of the present study demonstrate the limits of top-down attentional control. © 2011 The Author(s).

Religious beliefs affect the economic behavior of individuals. The aim of this study is to investigate the relation between religious beliefs and entrepreneurship. Empirical evidence that entrepreneurship rates differ among religions suggests that religious beliefs influence the pursuit of entrepreneurship. However, how and which specific religious beliefs play a role in this relationship remains unknown. Therefore, we study the relation between two key religious beliefs and entrepreneurship within one specific branch of Christianity, namely, Protestantism. Using a unique sample of 756 Christian protestant entrepreneurs and employees from the Netherlands, we show that protestant entrepreneurs have a stronger belief than comparable protestant employees that their work is a calling from God and that protestant entrepreneurs are more likely to perceive a duty to add value to society through their occupational work. These results indicate that research on the relation between religion and entrepreneurship is instrumental in explaining the engagement of people in entrepreneurship.