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Dendrite morphology, a neuron's anatomical fingerprint, is a neuroscientist's asset in unveiling organizational principles in the brain. However, the genetic program encoding the morphological identity of a single dendrite remains a mystery. In order to obtain a formal understanding of dendritic branching, we studied distributions of morphological parameters in a group of four individually identifiable neurons of the fly visual system. We found that parameters relating to the branching topology were similar throughout all cells. Only parameters relating to the area covered by the dendrite were cell type specific. With these areas, artificial dendrites were grown based on optimization principles minimizing the amount of wiring and maximizing synaptic democracy. Although the same branching rule was used for all cells, this yielded dendritic structures virtually indistinguishable from their real counterparts. From these principles we derived a fully-automated model-based neuron reconstruction procedure validating the artificial branching rule. In conclusion, we suggest that the genetic program implementing neuronal branching could be constant in all cells whereas the one responsible for the dendrite spanning field should be cell specific.

Abstract
Our brains continuously acquire sensory information and make judgments even when visual information is limited. In some circumstances, an ambiguous object can be recognized from how it moves, such as an animal hopping or a plane flying overhead. Yet it remains unclear how movement is processed by brain areas involved in visual object recognition. Here we investigate whether inferior temporal (IT) cortex, an area known for its relevance in visual form processing, has access to motion information during recognition. We developed a matching task that required monkeys to recognize moving shapes with variable levels of shape degradation. Neural recordings in area IT showed that, surprisingly, some IT neurons responded stronger to degraded shapes than clear ones. Furthermore, neurons exhibited motion sensitivity at different times during the presentation of the blurry target. Population decoding analyses showed that motion patterns could be decoded from IT neuron pseudo-populations. Contrary to previous findings, these results suggest that neurons in IT can integrate visual motion and shape information, particularly when shape information is degraded, in a way that has been previously overlooked. Our results highlight the importance of using challenging multifeature recognition tasks to understand the role of area IT in naturalistic visual object recognition.

Virtual reality (VR) technology has become increasingly prevalent in our society and has been used for a myriad of applications ranging from psychotherapy to training members of the military. However, one issue that arises from the use of VR is motion sickness, thus making predictors and indicators of motion sickness desirable. To date, a number of indicators of motion sickness have been derived based on nonlinear characteristics of human motion recorded using motion capture systems. While it is known that nonlinear measures can be used to predict motion sickness, it is not known whether people are perceptually sensitive to these particular nonlinear parameters. The aims of this study included establishing whether individuals consistently sort phase plots of sick and well individuals' postural motion without being explicitly told to do so; determining what nonlinear movement parameters could be used to represent these judgments; and assessing the stability of nonlinear measures found to be successful at predicting motion sickness by Smart et al. (2014). Through two methods of analysis (perceptual and quantitative), this research demonstrated that participants can indeed sort the graphic depictions of sick and well participants' postural motion and seem to be perceptually sensitive to nonlinear parameters (normalized path length, path length, elliptical area) that are known to be predictive of motion sickness.

After a brief overview of the film industry in Korea since 1926 the problems of this industry in South Korea since 1955 are discussed and analyzed. Measures adopted by various South Korean administrations to encourage the domestic film industry. New standards set for motion picture production companies by the Motion Picture Law of 1962. The importation of foreign films - a sensitive economic and cultural issue

AbstractWe report asymmetrical cortical responses (steady‐state visual evoked potentials) to radial expansion and contraction in human infants and adults. Forty‐four infants (22 3‐month‐olds and 22 4‐month‐olds) and nine adults viewed dynamic dot patterns which cyclically (2.1 Hz) alternate between radial expansion (or contraction) and random directional motion. The first harmonic (F1) response in the steady‐state VEP response must arise from mechanisms sensitive to the global radial motion structure. We compared F1 amplitudes between expansion‐random and contraction‐random motion alternations. F1 amplitudes for contraction were significantly larger than those for expansion for the older infants and adults but not for the younger infants. These results suggest that the human cortical motion mechanisms have asymmetrical sensitivity for radial expansion vs. contraction, which develops at around 4 months of age. The relation between development of sensitivity to radial motion and cortical motion mechanisms is discussed.

This article aims to explore the present state of tacit knowing of expertized motion that has been passed along from generation to generation in the learning process of Korean traditional performing arts. The current status of, and changes in, the learning process were observed in a questionnaire survey, and the effects of the use of motion-capture technology were examined in an experimental class. In the learning process of Korean traditional performing arts, active feedback loops exist and have been strengthened in which the learners monitor external information and reflect it with language, sensory images and somatic feelings through instructed and imitative learning. Although the traditional apprenticeship style of situated learning has tended to diminish, the learners are expanding their social networks beyond the boundaries of discipline and specialty. In the trial applying motion-capture technology, when imitative learning was partially substituted by instructive learning with visual expression and language, the students became sensitive to differences between the ideal motion and their actual performance. Motion-capture technology also provides new means of imitative learning with computer models. Emerging technologies will provide new opportunities to support tacit knowing in motion.

AbstractInfants are sensitive to biological motion, but do they recognize it as animate? As a first step towards answering this question, two experiments investigated whether 6‐month‐olds selectively attribute goals to shapes moving like animals. We habituated infants to a square moving towards one of two targets. When target locations were switched, infants reacted more to movement towards a new goal than a new location – but only if the square moved non‐rigidly and rhythmically, in a schematic version of bio‐mechanical movement older observers describe as animal‐like (Michotte, 1963). Goal attribution was specific to schematic animal motion: It did not occur if the square moved rigidly with the same rhythm as the animate stimulus, or if the square had the same amount of non‐rigid deformation, but in an inanimate configuration. The data would seem to show that perception of schematic animal motion is linked to a system for psychological reasoning from infancy. This in turn suggests that 6‐month‐olds may already interpret biological motion as animate.

Neuronal loss is the best neuropathological substrate that correlates with cortical atrophy and dementia in Alzheimer's disease (AD). Defective GABAergic neuronal functions may lead to cortical network hyperactivity and aberrant neuronal oscillations and in consequence, generate a detrimental alteration in memory processes. In this study, using immunohistochemical and stereological approaches, we report that the two major and non‐overlapping groups of inhibitory interneurons (SOM‐cells and PV‐cells) displayed distinct vulnerability in the perirhinal cortex of APP/PS1 mice and AD patients. SOM‐positive neurons were notably sensitive and exhibited a dramatic decrease in the perirhinal cortex of 6‐month‐old transgenic mice (57% and 61% in areas 36 and 35, respectively) and, most importantly, in AD patients (91% in Braak V–VI cases). In addition, this interneuron degenerative process seems to occur in parallel, and closely related, with the progression of the amyloid pathology. However, the population expressing PV was unaffected in APP/PS1 mice while in AD brains suffered a pronounced and significant loss (69%). As a key component of cortico‐hippocampal networks, the perirhinal cortex plays an important role in memory processes, especially in familiarity‐based memory recognition. Therefore, disrupted functional connectivity of this cortical region, as a result of the early SOM and PV neurodegeneration, might contribute to the altered brain rhythms and cognitive failures observed in the initial clinical phase of AD patients. Finally, these findings highlight the failure of amyloidogenic AD models to fully recapitulate the selective neuronal degeneration occurring in humans. ; This study was supported by Instituto de Salud Carlos III (ISCiii) of Spain, co‐financed by FEDER funds from European Union, through grants PI18/01557 (to AG) and PI18/01556 (to JV), and CIBERNED (to AG and JV), by Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucia Proyecto de Excelencia (CTS‐2035) (to JV and AG); by Malaga University grant PPIT.UMA.B1.2017/26 (to RSV). CND and JJFV were supported by FPI (Junta Andalucía) and FPU (Spanish Ministry of Science, Innovation and Universities) PhD fellowships, respectively. MMO held a Garantia Juvenil (Junta Andalucia) contract. RSV and JAGL held a postdoctoral contract from the University of Malaga, and AGA from CIBERNED. ; Peer reviewed

Abstract
γ-Aminobutyric acid type A receptors that incorporate α5 subunits (α5-GABAARs) are highly enriched in the hippocampus and are strongly implicated in control of learning and memory. Receptors located on pyramidal neuron dendrites have long been considered responsible, but here we report that mice in which α5-GABAARs have been eliminated from pyramidal neurons (α5-pyr-KO) continue to form strong spatial engrams and that they remain as sensitive as their pseudo-wild-type (p-WT) littermates to etomidate-induced suppression of place cells and spatial engrams. By contrast, mice with selective knockout in interneurons (α5-i-KO) no longer exhibit etomidate-induced suppression of place cells. In addition, the strength of spatial engrams is lower in α5-i-KO mice than p-WT littermates under control conditions. Consistent with the established role of the hippocampus in contextual fear conditioning, α5-i-KO mice resisted etomidate's suppression of freezing to context, but so too did α5-pyr-KO mice, supporting a role for extra-hippocampal regions in the development of contextual fear memory. Overall, our results indicate that interneuronal α5-GABAARs serve a physiological role in promoting spatial learning and that they mediate suppression of hippocampus-dependent contextual memory by etomidate.

Abstract. We propose a novel framework for assessing the risk associated with seismicity induced by hydraulic fracturing, which has been a notable source of recent public concern. The framework combines statistical forecast models for injection-induced seismicity, ground motion prediction equations, and exposure models for affected areas, to quantitatively link the volume of fluid injected during operations with the potential for nuisance felt ground motions. Such (relatively small) motions are expected to be more aligned with the public tolerance threshold for induced seismicity than larger ground shaking that could cause structural damage. This proactive type of framework, which facilitates control of the injection volume ahead of time for risk mitigation, has significant advantages over reactive-type magnitude and ground-motion-based systems typically used for induced seismicity management. The framework is applied to the region surrounding the Preston New Road shale gas site in North West England. A notable finding is that the calculations are particularly sensitive to assumptions of the seismicity forecast model used, i.e. whether it limits the cumulative seismic moment released for a given volume or assumes seismicity is consistent with the Gutenberg–Richter distribution for tectonic events. Finally, we discuss how the framework can be used to inform relevant policy.

The ability of fifty-four subjects to find and designate tactical military targets on a cathode-ray-tube display was evaluated as a function of five experimental variables. Results indicated that probability of detection was sensitive to variations in target type, target-to-background contrast, and image rate of motion, or time available for search. False positive rate was affected only by available search time. Implications of these results for the design of real-time reconnaissance systems are discussed.

When people speak, they gesture. However, is the audience watching a speaker who is sensitive to this link? We translated the body movements of politicians into stick-figure animations and separated the visual from the audio channel. We then asked participants to match a selection of five audio tracks (including the correct one) with the stick-figure animations. The participants made correct decisions in 65% of all cases (chance level of 20%). Matching voices with animations was less difficult when politicians showed expansive movements and spoke with a loud voice. Thus, people are sensitive to the link between motion cues and vocal cues, and this link appears to become even more apparent when a speaker shows expressive behaviors. Future work will have to refine and validate the methods applied and investigate how mismatches between communication channels affect the impressions that people form of politicians.

This is the author accepted manuscript. The final version is available from Springer Nature via the DOI in this record ; Bridge Weigh-in-Motion (B-WIM) systems use the bridge response under a traversing vehicle to estimate its axle weights. The information obtained from B-WIM systems has been used for a wide range of applications such as pre-selection for weight enforcement, traffic management/planning and for bridge and pavement design. However, it is less often used for bridge condition assessment purposes which is the main focus of this study. This paper presents a bridge damage detection concept using information provided by B-WIM systems. However, conventional B-WIM systems use strain measurements which are not sensitive to local damage. In this paper the authors present a B-WIM formulation that uses rotation measurements obtained at the bridge supports. There is a linear relationship between support rotation and axle weight and, unlike strain, rotation is sensitive to damage anywhere in the bridge. Initially, the sensitivity of rotation to damage is investigated using a hypothetical simply supported bridge model. Having seen that rotation is damage-sensitive, the influence of bridge damage on weight predictions is analysed. It is shown that if damage occurs, a rotation-based B-WIM system will continuously overestimate the weight of traversing vehicles. Finally, the statistical repeatability of ambient traffic is studied using real traffic data obtained from a Weigh-in-Motion site in the U.S. under the Federal Highway Administration's Long-Term Pavement Performance programme and a damage indicator is proposed as the change in the mean weights of ambient traffic data. To test the robustness of the proposed damage detection methodology numerical analysis are carried out on a simply supported bridge model and results are presented within the scope of this study. ; European Union's Horizon 2020

Autonomous underwater gliders (AUG) are a class of underwater vehicles that move using a buoyancy engine and forces from wings. Gliders execute turning motion with the help of a rudder or an internal roll control mechanism and the trajectory of the turn is a spiral. This paper analyses the sensitivity of the characteristics of spiral manoeuvre on the hydrodynamic coefficients of the glider. Based on the dynamics model of a gliding fish whose turn is enabled by a rudder, the effect of hydrodynamic coefficients of the hull and the rudder on the spiral motion are quantified. Local sensitivity analysis is undertaken using the indirect method. The order of importance of hydrodynamic coefficients is evaluated. It is observed that the spiral path parameters are most sensitive to the side force created by the rudder and the effect of the drag coefficient is predominant to that of the lift coefficients. This study will aid in quantifying the effect of change of geometry on the manoeuvrability of AUGs.