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Motion vision provides important cues for many tasks. Flying insects, for example, may pursue small, fast moving targets for mating or feeding purposes, even when these are detected against self-generated optic flow. Since insects are small, with size-constrained eyes and brains, they have evolved to optimize their optical, neural and behavioral target visualization solutions. Indeed, even if evolutionarily distant insects display different pursuit strategies, target neuron physiology is strikingly similar. Furthermore, the coarse spatial resolution of the insect compound eye might actually be beneficial when it comes to detection of moving targets. In conclusion, tiny insects show higher than expected performance in target visualization tasks.

Objectives: Sickness absence in workplaces may reflect working conditions. It may also reflect a "healthy hire effect," i.e., that workplaces recruit individuals with experience of sickness absence differently. The purpose of the study was to determine if a history of sickness absence among recruits is associated with the average level of sickness absence in workplaces. Material and Methods: In a register-based follow-up study, Swedish workplaces with at least 5 employees in 2006 were selected (approximately 127 000 workplaces with 3.9 million employees). The workplaces were categorized according to the average workplace sickness absence in 2006 and the recruits were categorized according to the individual sickness absence in 2005. The workplaces with a high average level of sickness absence were more likely than those with a low level to hire employees with high sickness absence in the year preceding employment: men - odds ratio (OR) = 7.2, 95% confidence interval (CI): 6.6-7.8, women OR = 7.5, 95% CI: 6.9-8.1. Results: The results show that there is a greater likelihood of employing individuals with high levels of sickness absence in the workplaces with many days of the average sickness absence than in the workplaces with few days of the average sickness absence. Conclusions: The results suggest that sickness absence in workplaces may reflect a healthy hire effect., Funding Agencies|AFA Insurance [090299]

Animal sensory systems are optimally adapted to those features typically encountered in natural surrounds, thus allowing neurons with limited bandwidth to encode challengingly large input ranges. Natural scenes are not random, and peripheral visual systems in vertebrates and insects have evolved to respond efficiently to their typical spatial statistics. The mammalian visual cortex is also tuned to natural spatial statistics, but less is known about coding in higher order neurons in insects. To redress this we here record intracellularly from a higher order visual neuron in the hoverfly. We show that the cSIFE neuron, which is inhibited by stationary images, is maximally inhibited when the slope constant of the amplitude spectrum is close to the mean in natural scenes. The behavioural optomotor response is also strongest to images with naturalistic image statistics. Our results thus reveal a close coupling between the inherent statistics of natural scenes and higher order visual processing in insects., Supplementary information available for this article at http://www.nature.com/ncomms/2015/151006/ncomms9522/suppinfo/ncomms9522_S1.html

White noise techniques have been used widely to investigate sensory systems in both vertebrates and invertebrates. White noise stimuli are powerful in their ability to rapidly generate data that help the experimenter decipher the spatio-temporal dynamics of neural and behavioral responses. One type of white noise stimuli, maximal length shift register sequences (m-sequences), have recently become particularly popular for extracting response kernels in insect motion vision. We here use such m-sequences to extract the impulse responses to figure motion in hoverfly lobula plate tangential cells (LPTCs). Figure motion is behaviorally important and many visually guided animals orient towards salient features in the surround. We show that LPTCs respond robustly to figure motion in the receptive field. The impulse response is scaled down in amplitude when the figure size is reduced, but its time course remains unaltered. However, a low contrast stimulus generates a slower response with a significantly longer time-to-peak and half-width. Impulse responses in females have a slower time-to-peak than males, but are otherwise similar. Finally we show that the shapes of the impulse response to a figure and a widefield stimulus are very similar, suggesting that the figure response could be coded by the same input as the widefield response.

The classical Hassenstein-Reichardt mathematical elementary motion detector (EMD) model is treated analytically. The EMD is stimulated with drifting sinusoidal gratings, which are often used in motion vision research, thus enabling direct comparison with neural responses from motion-sensitive neurones in the fly brain. When sinusoidal gratings are displayed on a cathode ray tube monitor, they are modulated by the refresh rate of the monitor. This generates a pulsatile signature of the visual stimulus, which is also seen in the neural response. Such pulsatile signals make a Laguerre domain identification method for estimating the parameters of a single EMD suitable, allowing estimation of both finite and infinite-dimensional dynamics. To model the response of motion-sensitive neurones with large receptive fields, a pool of spatially distributed EMDs is considered, with the weights of the contributing EMDs fitted to the neural data by a sparse estimation method. Such an EMD-array is more reliably estimated by stimulating with multiple sinusoidal gratings, since these provide higher spatial excitation than a single sinusoidal grating. Consequently, a way of designing the visual stimuli for a certain order of spatial resolution is suggested.

Predatory animals have evolved to optimally detect their prey using exquisite sensory systems such as vision, olfaction and hearing. It may not be so surprising that vertebrates, with large central nervous systems, excel at predatory behaviors. More striking is the fact that many tiny insects, with their miniscule brains and scaled down nerve cords, are also ferocious, highly successful predators. For predation, it is important to determine whether a prey is suitable before initiating pursuit. This is paramount since pursuing a prey that is too large to capture, subdue or dispatch will generate a substantial metabolic cost (in the form of muscle output) without any chance of metabolic gain (in the form of food). In addition, during all pursuits, the predator breaks its potential camouflage and thus runs the risk of becoming prey itself. Many insects use their eyes to initially detect and subsequently pursue prey. Dragonflies, which are extremely efficient predators, therefore have huge eyes with relatively high spatial resolution that allow efficient prey size estimation before initiating pursuit. However, much smaller insects, such as killer flies, also visualize and successfully pursue prey. This is an impressive behavior since the small size of the killer fly naturally limits the neural capacity and also the spatial resolution provided by the compound eye. Despite this, we here show that killer flies efficiently pursue natural (Drosophila melanogaster) and artificial (beads) prey. The natural pursuits are initiated at a distance of 7.9 ± 2.9 cm, which we show is too far away to allow for distance estimation using binocular disparities. Moreover, we show that rather than estimating absolute prey size prior to launching the attack, as dragonflies do, killer flies attack with high probability when the ratio of the prey's subtended retinal velocity and retinal size is 0.37. We also show that killer flies will respond to a stimulus of an angular siz

Antologin 'Erziehung in der europäischen Literatur des 19. Jahrhunderts' tar upp europeiska skönlitterära verk från 1800-talet och diskuterar deras förståelse av fostran. Kapitlet 'Erziehung am Rande der Gesellschaft. Emilie Flygare-Carléns Die Rose von Tistelön' presententerar ett svenskt verk. Handlingen utspelar sig bland Bohusläns fattiga befolkning och tematiserar de hårda livsvillkoren. I centrum står smugglardotters uppväxt och fostran. Denna syftar till att förmedla borgerliga värden till den kriminella familjens barn som lever avskilt på Tistelön. Antologibidraget diskuterar forstran utifrån ett periferi-centrum tema som kopplas till författarinnans biografi.

Many animals use visual motion cues for navigating within their surroundings. Both flies and vertebrates compute local motion by temporal correlation of neighboring photoreceptors, via so-called elementary motion detectors (EMDs). In the fly lobula plate and the vertebrate visual cortex the output from many EMDs is pooled in neurons sensitive to wide-field optic flow. Although the EMD has been the preferred model for more than 50 years, recent work has highlighted its limitations in describing some visual behaviors, such as responses to higher-order motion stimuli. Non-EMD motion processing may therefore serve an important function in vision. Here, we describe a novel neuron class in the fly lobula plate that clearly does not derive its input from classic EMDs. The centrifugal stationary inhibited flicker excited (cSIFE) neuron is strongly excited by flicker, up to very high temporal frequencies. The non-EMD driven flicker sensitivity leads to strong, nondirectional responses to high-speed, wide-field motion. Furthermore, cSIFE is strongly inhibited by stationary patterns, within a narrow wavelength band. cSIFE's outputs overlap with the inputs of well described optic flow-sensitive lobula plate tangential cells (LPTCs). Driving cSIFE affects the active dendrites of LPTCs, and cSIFE may therefore play a large role in motion vision.

Visual systems adapt rapidly to objects moving repeatedly within the visual field, because such objects are likely irrelevant. In the crab, the neural switch for such adaptation has been found to take place at a surprisingly early stage of the visual processing pathway.

A Laguerre domain approach to the identification of the so-called Elementary Motion Detector (EMD) that is hypothesized to constitute the basis of biological motion vision in nearly all animals is proposed. Despite the vast popularity of the EMD concept in both biology and biologically inspired computer vision, the problem of estimating the dynamics of the EMD from experimental data has been poorly addressed. The choice of the Laguerre domain for the representation of the input and the output of the EMD is motivated by the pulse-modulated character of the visual stimuli produced by the CRT displays that are often used in animal experiments. An analytical expression for the Laguerre spectrum of the EMD output given the Laguerre spectrum of the input is derived and a parameter estimation algorithm of the system dynamics is developed. The feasibility of the approach is illustrated by simulation using actual visual stimuli from fly electrophysiology.

The classical mathematical elementary motion detector (EMD) model stimulated with sinusoidal and pulsatile input signals is treated analytically. Drifting sinusoidal gratings are often used in insect vision research, enabling direct comparison with biological data. When displayed on a cathode ray tube monitor, the sinusoidal grating is modulated by the refresh rate of the monitor. Due to the resulting pulsatile nature of the visual stimuli and the corresponding biological response, a Laguerre domain identification method for estimating the dynamics of a single EMD appears to be suitable. A pool of spatially distributed EMDs is considered as the model for the measured neural output. The weights of the contributing EMDs are evaluated by a sparse optimization method to fit the experimental data.

Personalized nutrition has the potential to enhance individual health control. It could be seen as a means to strengthen people’s autonomy as they learn more about their personal health risks, and receive dietary advice accordingly. We examine in what sense personalized nutrition strengthens or weakens individual autonomy. The impact of personalized nutrition on autonomy is analyzed in relation to responsibility and trustworthiness. On a societal level, individualization of health promotion may be accompanied by the attribution of extended individual responsibility for one’s health. This constitutes a dilemma of individualization, caused by a conflict between the right to individual freedom and societal interests. The extent to which personalized nutrition strengthens autonomy is consequently influenced by how responsibility for health is allocated to individuals. Ethically adequate allocation of responsibility should focus on prospective responsibility and be differentiated with regard to individual differences concerning the capacity of adults to take responsibility. The impact of personalized nutrition on autonomy also depends on its methodological design. Owing to the complexity of information received, personalized nutrition through genetic testing (PNTGT) is open to misinterpretation and may not facilitate informed choices and autonomy. As new technologies, personalized nutrition and PNTGT are subject to issues of trust. To strengthen autonomy, trust should be approached in terms of trustworthiness. Trustworthiness implies that an organization that develops or introduces personalized nutrition can show that it is competent to deal with both the technical and moral dimensions at stake and that its decisions are motivated by the interests and expectations of the truster., This study was conducted on behalf of the Food4Me project.Food4Me is the acronym of the EU FP7 project: “Personalised nutrition: an integrated analysis of opportunities and challenges” (Contract no. KBBE.2010.2.3-02, Project no. 265494). The parties involved in the project are listed on the project’s web site http://www.food4me.org/. Project coordination was carried out at University College Dublin, Ireland, Institute of Food and Health; Project Coordinator: Professor Michael J. Gibney, Project Manager: Dr. Marianne Walsh. For overall correspondence regarding the Food4Me project: Professor Michael J Gibney, UCD Institute of Food and Health, University College Dublin, Dublin, Ireland, Tel: +353 (1) 716 2824, e-mail: mike.gibney@ucd.i.e., Food4Me

In personalized nutrition, food is a tool for good health, implying an instrumental relationship between food and health. Food receives a secondary value, while health would appear to be a descriptive biological concept. This article gives an introduction to cultural understandings of food and health. The wider definition of food and health is explored in relation to the commonly used scientific approach that tends to take a more reductionist approach to food and health. The different discourses on food and health are being discussed in relation to ethical aspects of personalized nutrition. The success of personalized nutrition is likely dependent upon the ability to integrate the scientific approach with everyday cultural, emotional, ethical, and sensual understandings of food. Health theories can be divided into two principal rival types—biostatistical and holistic. Biostatistical focuses on survival, while holistic focuses on ability as a precondition for health. Arguments in favor of a holistic and individualistic theory of health and illness are presented. This implies a focus on the ability of the individual to realize his or her “vital goals.” A holistic and individualistic health concept may have a reinforcing effect on the individualized approach in personalized nutrition. It allows focus on individual health premises and related dietary means of health promotion, as well as an individualized perspective on the objectives of health promotion. An individualistic notion of health also indicates that people with high levels of vital goals benefit more easily. To reach beyond these groups is likely difficult. This potential injustice should be balanced with global preventive medical programs., This study was conducted on behalf of the Food4Me project. Food4Me is the acronym of the EU FP7 project: “Personalised nutrition: an integrated analysis of opportunities and challenges” (Contract No. KBBE.2010.2.3-02, Project No. 265494). The parties involved in the project are listed on the project’s Web site http://www.food4me.org/. Project coordination was carried out at University College Dublin, Ireland, Institute of Food and Health; Project Coordinator: Professor Michael J Gibney, Project Manager: Dr. Marianne Walsh. For overall correspondence regarding the Food4Me project: Professor Michael J Gibney, UCD Institute of Food and Health, University College Dublin, Dublin, Ireland, Tel: +353 (1) 716 2824, e-mail: mike.gibney@ucd.ie., Food4Me

Consumers often have a positive attitude to the option of receiving personalized nutrition advice based upon genetic testing, since the prospect of enhancing or maintaining one’s health can be perceived as empowering. Current direct-to-consumer services over the Internet, however, suffer from a questionable level of truthfulness and consumer protection, in addition to an imbalance between far-reaching promises and contrasting disclaimers. Psychological and behavioral studies indicate that consumer acceptance of a new technology is primarily explained by the end user’s rational and emotional interpretation as well as moral beliefs. Results from such studies indicate that personalized nutrition must create true value for the consumer. Also, the freedom to choose is crucial for consumer acceptance. From an ethical point of view, consumer protection is crucial, and caution must be exercised when putting nutrigenomic-based tests and advice services on the market. Current Internet offerings appear to reveal a need to further guaranty legal certainty by ensuring privacy, consumer protection and safety. Personalized nutrition services are on the borderline between nutrition and medicine. Current regulation of this area is incomplete and undergoing development. This situation entails the necessity for carefully assessing and developing existing rules that safeguard fundamental rights and data protection while taking into account the sensitivity of data, the risks posed by each step in their processing, and sufficient guarantees for consumers against potential misuse.

The paper is accepted for publication in the conference procceedings volume.

Interpreting visual motion within the natural environment is a challenging task, particularly considering that natural scenes vary enormously in brightness, contrast and spatial structure. Current models for the detection of self-generated optic flow depend heavily on these very parameters, but despite this, animals manage to successfully navigate within a broad range of scenes. Within global scenes local areas with more salient features are common. Recent work has highlighted the influence that local, salient features have on the encoding of optic flow, but it has been difficult to quantify how local transient responses affect responses to subsequent features and thus contribute to the global neural response. To investigate this in more detail we used experimenter-designed stimuli and recorded intracellularly from motion-sensitive neurons. We limited the stimulus to a small vertically elongated strip, to investigate local and global neural responses to pairs of local ￜdoubletￜ features that were designed to interact with each other in the temporal and spatial domain. We show that the passage of a high contrast doublet feature produces a complex transient response from local motion detectors consistent with predictions of a simple computational model. In the neuron, the passage of a high-contrast feature induces a local reduction in responses to subsequent low contrast features. However, this neural contrast gain reduction appears to be recruited only when features stretch vertically (i.e. orthogonal to the direction of motion) across at least several aligned neighbouring ommatidia. Horizontal displacement of the components of elongated features abolishes the local adaptation effect. It is thus likely that features in natural scenes with vertically aligned edges, such as tree trunks, would be expected to recruit the greatest amount of response suppression, which could emphasize the local responses to such features vs those in nearby texture within the scene.

Despite being equipped with low-resolution eyes and tiny brains, many insects show exquisite abilities to detect and pursue targets even in highly textured surrounds. Target tracking behavior is subserved by neurons that are sharply tuned to the motion of small high-contrast targets. These neurons respond robustly to target motion, even against self-generated optic flow. A recent model, supported by neurophysiology, generates target selectivity by being sharply tuned to the unique spatiotemporal profile associated with target motion. Target neurons are likely connected in a complex network where some provide more direct output to behavior, whereas others serve an inter-regulatory role. These interactions may regulate attention and aid in the robust detection of targets in clutter observed in behavior.

In higher-order motion stimuli, the direction of object motion does not follow the direction of luminance change. Such stimuli could be generated by the wing movements of a flying butterfly and further complicated by its motion in and out of shadows. Human subjects readily perceive the direction of higher-order motion, although this stands in stark contrast to prevailing motion vision models. Flies and humans compute motion in similar ways, and because flies behaviorally track bars containing higher-order motion cues, they become an attractive model system for investigating the neurophysiology underlying higher-order motion sensitivity. We here use intracellular electrophysiology of motion-vision-sensitive neurons in the hoverfly lobula plate to quantify responses to stimuli containing higher-order motion. We show that motion sensitivity can be broken down into two separate streams, directionally coding for elementary motion and figure motion, respectively, and that responses to Fourier and theta motion can be predicted from these. The sensitivity is affected both by the stimulus' time course and by the neuron's underlying receptive field. Responses to preferred-direction theta motion are sexually dimorphic and particularly robust along the visual midline.

Sensory systems adapt to prolonged stimulation by decreasing their response to continuous stimuli. Whereas visual motion adaptation has traditionally been studied in immobilized animals, recent work indicates that the animal's behavioral state influences the response properties of higher-order motion vision-sensitive neurons. During insect flight octopamine is released, and pharmacological octopaminergic activation can induce a fictive locomotor state. In the insect optic ganglia, lobula plate tangential cells (LPTCs) spatially pool input from local elementary motion detectors (EMDs) that correlate luminosity changes from two spatially discrete inputs after delaying the signal from one. The LPTC velocity optimum thereby depends on the spatial separation of the inputs and on the EMD's delay properties. Recently it was shown that behavioral activity increases the LPTC velocity optimum, with modeling suggesting this to originate in the EMD's temporal delay filters. However, behavior induces an additional post-EMD effect: the LPTC membrane conductance increases in flying flies. To physiologically investigate the degree to which activity causes presynaptic and postsynaptic effects, we conducted intracellular recordings of Eristalis horizontal system (HS) neurons. We constructed contrast response functions before and after adaptation at different temporal frequencies, with and without the octopamine receptor agonist chlordimeform (CDM). We extracted three motion adaptation components, where two are likely to be generated presynaptically of the LPTCs, and one within them. We found that CDM affected the early, EMD-associated contrast gain reduction, temporal frequency dependently. However, a CDM-induced change of the HS membrane conductance disappeared during and after visual stimulation. This suggests that physical activity mainly affects motion adaptation presynaptically of LPTCs, whereas post-EMD effects have a minimal effect.