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BackgroundMyokines, released from the contracting muscle, enable communication between the working muscles and other tissue. Their release during physical exercise is assumed to depend on mode, duration, and intensity.ObjectiveThe aim is to examine the acute changes in circulating levels of the myokines IL-6, IL-10, and IL-1ra induced by a bout of resistance exercise and to consider potential moderators of the results.MethodsSystematic literature search was conducted for resistance exercise intervention studies measuring IL-6, IL-10, or IL-1ra before and immediately after resistance exercise in healthy individuals. Random effects meta-analysis was performed for each myokine.ResultsA small to moderate positive effect of resistance exercise for IL-6 and a moderate to large positive effect for IL-1ra were detected. This could not be shown for IL-10. No moderators of the results were detected.ConclusionThis systematic review and meta-analysis clearly showed the immediate positive effects of an acute resistance exercise session on IL-6 and IL-1ra levels.

Abstract As an alternative to chemical building blocks derived from algal biomass, the excretion of glycolate has been proposed. This process has been observed in green algae such as Chlamydomonas reinhardtii as a product of the photorespiratory pathway. Photorespiration generally occurs at low CO2 and high O2 concentrations, through the key enzyme RubisCO initiating the pathway via oxygenation of 1.5-ribulose-bisphosphate. In wild-type strains, photorespiration is usually suppressed in favour of carboxylation due to the cellular carbon concentrating mechanisms (CCMs) controlling the internal CO2 concentration. Additionally, newly produced glycolate is directly metabolized in the C2 cycle. Therefore, both the CCMs and the C2 cycle are the key elements which limit the glycolate production in wild-type cells. Using conventional crossing techniques, we have developed Chlamydomonas reinhardtii double mutants deficient in these two key pathways to direct carbon flux to glycolate excretion. Under aeration with ambient air, the double mutant D6 showed a significant and stable glycolate production when compared to the non-producing wild type. Interestingly, this mutant can act as a carbon sink by fixing atmospheric CO2 into glycolate without requiring any additional CO2 supply. Thus, the double-mutant strain D6 can be used as a photocatalyst to produce chemical building blocks and as a future platform for algal-based biotechnology. Key Points • Chlamydomonas reinhardtii cia5 gyd double mutants were developed by sexual crossing • The double mutation eliminates the need for an inhibitor in glycolate production • The strain D6 produces significant amounts of glycolate with ambient air only

The ability of springboard divers to perform and control difficult elements with multiple twisted somersaults before entering the water is of great interest for coaches and researchers. In order to produce twists within somersaults, divers use both 'contact' and 'aerial' techniques. After completing body axes rotations, head movements seem to be important, as they enable visual information in the air. The current study aims at investigating angular velocities around the longitudinal axis in combination with head movements of 13 springboard divers during twisted somersaults. Divers performed forward and backward somersaults with different numbers of half twists. The results revealed maximum longitudinal axis angular velocities between 500°/s and 1300°/s. Moreover, results showed that the use of contact technique was greater in twisted somersaults with backward approaches, and thus higher angular velocities could be achieved. While finishing the twists, head movements in the opposite direction to the longitudinal axis rotation occurred, which allow divers to orient themselves. Twist speeds influenced athletes' head movements to have greater angles and greater rotational velocities. Therefore, it is concluded that fast head movements are necessary in difficult twisted dives to allow orientation in the short phase between finishing the twist and entering the water surface.

In a ball catching task, the catcher guides their hand to the ball's future trajectory. The hand may start to move even before the exact position is known, and the interceptive movement may be corrected online. Using a recent method for detecting the phases of catching movements we investigate how juggling experience, self-throwing, and delayed visibility of the ball, influence the timing of the hand's trajectory. Specifically, we analyze the time from which the goal position of the movement is known, i.e., the time from which the movement becomes smooth. Seventeen jugglers and twenty controls caught ten balls per each of eight conditions. The results indicate that experts' catching movements acquire the smooth nature of goal-directed movements earlier than novices catching movements do.

Plant monocultures growing for extended periods face severe losses of productivity. This phenomenon, known as ‘yield decline’, is often caused by the accumulation of above- and belowground plant antagonists. The effectiveness of plant defences against antagonists might help explaining differences in yield decline among species. Using a trait-based approach, we studied the role of 20 physical and chemical defence traits of leaves and fine roots on yield decline of 18-year old monocultures of 27 grassland species. We hypothesized that yield decline is lower for species with high defences, that root defences are better predictors of yield decline than leaf defences, and that in roots, physical defences better predict yield decline than chemical defences, while the reverse is true for leaves. We additionally hypothesized that species increasing the expression of defence traits after long-term monoculture growth would suffer less yield decline. We summarized leaf and fine root defence traits using principal component analysis and analysed the relationship between defence traits mean as a measure of defence strenght and defence traits temporal changes of the most informative components and monoculture yield decline. The only significant predictors of yield decline were the mean and temporal changes of the component related to specific root length and root diameter (e.g. the so called collaboration gradient of the root economics space). The principal component analysis of the remaining traits showed strong trade-offs between defences suggesting that different plant species deploy a variety of strategies to defend themselves. This diversity of strategies could preclude the detection of a generalized correlation between the strength and temporal changes of defence gradients and yield decline. Our results show that yield decline is strongly linked to belowground processes particularly to root traits. Further studies are needed to understand the mechanism driving the effect of the collaboration gradient on yield decline.

Animals display rich and coordinated motor patterns during walking and running. Previous modelling as well as experimental results suggest that the balance between excitation and inhibition in neural networks may be critical for generating such structured motor patterns. However, biological neural networks have an anatomical imbalance between excitatory and inhibitory neural populations. We explore the influence of such an anatomical imbalance on the ability of a reservoir computing artificial neural network to learn human locomotor patterns for slow walking, fast walking and running. We varied the numbers of neurons, connections percentages and connection strengths of excitatory and inhibitory populations. We showed that performance depended on the network anatomy. First, it deteriorated when the total number of neurons was too small or the total connection strength was too large. Second, performance was critically dependent on the balance between excitation and inhibition. Imbalance towards excitation caused a reduction in the richness of internal network dynamics, leading to a stereotypical motor output and poor overall performance. In contrast, rich internal dynamics and good overall performance were found when the network anatomy was either balanced or imbalanced towards inhibition. This suggests that motor pattern generation may be robust to increased inhibition but not increased excitation in neural networks.1Author summaryHow does the anatomy of the nervous system allow the generation of the complex motor patterns observed during the movements of humans and other animals? We explore this question in a model of the spinal cord in which we vary the neural anatomy. We find that movement generation requires the neural network to have rich internal dynamics. Such rich internal dynamics emerge from the interaction between the excitatory and inhibitory neurons in the network. Strong inhibition causes fluctuations in the neural activity which allow rich motor patterns to be produced. However, strong excitation quenches these fluctuations and causes a reduction in the variability of motor patterns. When both excitation and inhibition are strong, the neural activity becomes chaotic, and dysfunctional, highly variable motor patterns are produced. We therefore predict that diseases of the nervous system which affect inhibitory and excitatory neurons differently will have a different signature in terms of motor patterns. Diseases causing increased excitation in neural circuits should lead to stereotypical motor behaviors, whereas diseases causing increased excitation and inhibition should lead to unstable motor patterns.

Ethylene glycol (EG) is obtained by a novel, two-step approach combining a biotechnological and a heterogeneously catalyzed step. First, microalgae are cultivated to photobiocatalytically yield glycolic acid (GA) by means of photosynthesis from CO

The nervous system integrates the immune system in the systemic effort to maintain or restore the organism's homeostasis. Acute bouts of exercise may alter the activity of specific pathways associated with neuroendocrine regulation of the immune system.To examine the acute effects of heavy resistance exercise on biomarkers of neuroendocrine-immune regulation in healthy adults.A systematic literature search was conducted using PubMed, Cochrane Controlled Trials Register, Web of Science and SportDiscus with no date restrictions up to March 2021. Clinical trials in English or German were included if they measured the blood plasma or serum concentrations of specific biomarkers of neuroendocrine-immune regulation (adrenaline, noradrenaline, acetylcholine, vasoactive intestinal peptide (VIP), cortisol, growth hormone, calcitonin gene-related peptide (CGRP), substance p, serotonin, brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF) or glia-derived neurotrophic factor (GDNF)) in a resting state prior to and no later than 60 minutes after an acute bout of heavy resistance exercise in healthy adults.7801 records were identified through literature search, of which 36 studies, with a total of 58 intervention groups, met the inclusion criteria. Evidence was found that an acute bout of heavy resistance exercise increased the levels of adrenaline (median: 185%), noradrenaline (median: 113%) and GH (median: 265%) immediately after the exercise. Mixed results were found for cortisol (median: 0%), suggesting that its response might be more sensitive to the configuration of the exercise scheme. The limited evidence regarding the effects on BDNF and ACTH allows no firm conclusions to be drawn about their response to heavy resistance exercise. The vast majority of the included studies reported a return of the biomarker concentrations to their baseline value within one hour after the termination of the exercise bout. No studies were identified that investigated the response of acetylcholine, VIP, CGRP, substance p, serotonin, NGF or GDNF to heavy resistance exercise.A bout of heavy resistance exercise alters the circulating concentrations of selected biomarkers of neuroendocrine-immune regulation. Both subject characteristics, such as sex as well as exercise parameters, such as rest intervals appear to have the potential to influence these effects.

The pandemic coronavirus disease 2019 (COVID-19) can cause multi-systemic symptoms that can persist beyond the acute symptomatic phase. The post-acute sequelae of COVID-19 (PASC), also referred to as long COVID, describe the persistence of symptoms and/or long-term complications beyond 4 weeks from the onset of the acute symptoms and are estimated to affect at least 20% of the individuals infected with SARS-CoV-2 regardless of their acute disease severity. The multi-faceted clinical picture of long COVID encompasses a plethora of undulating clinical manifestations impacting various body systems such as fatigue, headache, attention disorder, hair loss and exercise intolerance. The physiological response to exercise testing is characterized by a reduced aerobic capacity, cardiocirculatory limitations, dysfunctional breathing patterns and an impaired ability to extract and use oxygen. Still, to this day, the causative pathophysiological mechanisms of long COVID remain to be elucidated, with long-term organ damage, immune system dysregulation and endotheliopathy being among the hypotheses discussed. Likewise, there is still a paucity of treatment options and evidence-based strategies for the management of the symptoms. In sum, this review explores different aspects of long COVID and maps the literature on what is known about its clinical manifestations, potential pathophysiological mechanisms, and treatment options.

Due to the redundancy of our motor system, movements can be performed in many ways. While multiple motor control strategies can all lead to the desired behavior, they result in different joint and muscle forces. This creates opportunities to explore this redundancy, e.g., for pain avoidance or reducing the risk of further injury. To assess the effect of different motor control optimization strategies, a direct measurement of muscle and joint forces is desirable, but problematic for medical and ethical reasons. Computational modeling might provide a solution by calculating approximations of these forces. In this study, we used a full-body computational musculoskeletal model to (1) predict forces measured in knee prostheses during walking and squatting and (2) to study the effect of different motor control strategies (i.e., minimizing joint force vs. muscle activation) on the joint load and prediction error. We found that musculoskeletal models can accurately predict knee joint forces with an RMSE of, 19 pages, 4 figures

Christian Ottersbach, Heiko Wagner, Jörg Wöllper: Festungen in Baden-Württemberg. Verlag Schnell und Steiner Regensburg 2014. 240 Seiten mit über 200, meist farbigen Abbildungen und Plänen. Klappenbroschur € 16,95. ISBN 978-3-7954-2826-6

Registration aims to decompose amplitude and phase variation of samples of curves. Phase variation is captured by warping functions which monotonically transform the domains. Resulting registered curves should then only exhibit amplitude variation. Most existing methods assume that all sample functions exhibit a typical sequence of shape features like peaks or valleys, and registration focuses on aligning these features. A more general perspective is adopted which goes beyond feature alignment. A registration method is introduced where warping functions are defined in such a way that the resulting registered curves span a low dimensional linear function space. The approach may be used as a tool for analyzing any type of functional data satisfying a structural regularity condition called bounded shape variation. Problems of identifiability are discussed in detail, and connections to established registration procedures are analyzed. The method is applied to real and simulated data.

Statistical growth rate modelling can be applied in a variety of ecological and biotechnological applications. Such models are frequently based on Monod or Droop equations and, especially for the latter, require reliable determination of model input parameters such as C:N quotas. Besides growth rate modelling, a C:N quota quantification can be useful for monitoring and interpretation of physiological acclimation to abiotic and biotic disturbances (e.g., nutrient limitations). However, as high throughput C:N quota determination is difficult to perform, alternatives need to be established. Fourier-transformed infrared (FTIR) spectroscopy is used to analyze a variety of biochemical, chemical, and physiological parameters in phytoplankton. Hence, a quantification of the C:N quota should also be feasible. Therefore, using FTIR spectroscopy, six phytoplankton species from among different phylogenetic groups have been analyzed to determine the effect of nutrient limitation on C:N quota patterns. The typical species-specific response to increasing nitrogen limitation was an increase in the C:N quota. Irrespective of this species specificity, we were able to develop a reliable multi-species C:N quota prediction model based on FTIR spectroscopy using the partial least square regression (PLSR) algorithm. Our data demonstrate that the PLSR approach is more robust in C:N quota quantification (R2 = 0.93) than linear correlation of C:N quota versus growth rate (R2 ranges from 0.74 to 0.86) or biochemical information based on FTIR spectra (R2 ranges from 0.82 to 0.89). This accurate prediction of C:N values may support high throughput measurements in a broad range of future approaches.

Maneuverability is of paramount importance for many animals, e.g., in predator-prey interactions. Despite this fact, quadrupedal limb behavior in complicated maneuvers like simultaneous jumping and turning are not well studied. Twenty adult sport Border Collies were recorded while jumping over an obstacle and simultaneously turning. Kinetic and kinematic data were captured in synchrony using eight force plates and sixteen infrared cameras. These dogs were familiar with the task through regular participation in the dog sport agility. The experiments revealed that during landing, higher lateral forces acting in the forelimbs compared to hindlimbs. During landing, the outer limbs produced about twice the inner limbs' force in both vertical and lateral directions, showing their dominant contribution to turning. Advanced dogs showed significantly higher lateral impulse and stronger inner-outer limb asymmetry regarding lateral impulses than beginner dogs, leading to significantly stronger turning for advanced dogs. Somewhat unexpected, skill effects rarely explained global limb dynamics, indicating that landing a turn jump is a constrained motion. Constrained motions leave little space for individual techniques suggesting that the results can be generalized to quadrupedal turn jumps in other animals.

Low-velocity motor vehicle crashes frequently induce chronic neck disorders also referred to as whiplash-associated disorders (WAD). The etiology of WAD is still not fully understood. Women are affected more often and more severely than men. A frontal-oblique collision direction leads to WAD relatively frequently, but is poorly investigated as compared to rear-end or frontal collision directions. An oblique impact direction is assumed to strain the contralateral neck side more than the ipsilateral side, provoking an asymmetrical response pattern of the left and right cervical muscles. In this study, we examined the muscle reflex responses of the sternocleidomastoid, the paraspinal, and the trapezius muscles as well as the kinematic responses of 60 subjects during left-frontal-oblique collisions. Neither the reflex delay nor the peak head acceleration revealed significant sex differences. Thus, the elsewhere reported higher injury risk of females as compared to males cannot be explained by the electromyographic and kinematic results of this study. In females as well as in males the right muscle responses revealed shorter onset times than the left muscle responses. Thus, cervical muscles seem to be activated depending on the specific direction of the impact. Moreover, the difference between right and left muscle responses cannot be explained by a startle reflex. The movement of the head in relation to the torso (female mean ± SD: 92 ± 16 ms; male: 87 ± 16 ms) started almost simultaneously to the onset of the first muscle activation (right paraspinal muscles: female mean: 95 ms and 95%-CI 82 − 109; male mean: 95 ms and 95%-CI 84 − 108) indicating that the initial muscle activity seems not to be triggered by a stretch reflex in the PARA muscles.

According to the literature, persons with intellectual disabilities have poor motor control in tasks in which motor anticipation is needed. Our study aimed to assess their motor behavior during interceptive tasks (a tennis ball interception with external-and-oneself throw conditions). A stick-bar was used as a reference or to support cloth to occlude a ball’s trajectory. Catch performance and interceptive behavior were analyzed (26 persons). The results show that high/low values of the initial approaching movement led to successful/successful catches, respectively. Our results are in line with the literature about the impact of poor motor control on performance in those with intellectual disabilities. We suggest that low anticipation may relate to problems in real-life situations.

In motion analysis marker sets or protocols are mostly developed for gait analysis and it has been shown that the marker set used affects the results of gait analysis. These marker sets are also used for the analysis of high dynamic sports movements. Single-leg landings are a common tool to investigate functional knee stability and further to predict injury risks where frontal plane motion and loading seem to play an important role. Until now, it is unknown how the marker sets affect the motion analysis results of such high dynamic movements. Therefore, the aim of the study was to compare six different marker sets. Three-dimensional motion and force data of single-leg landings in 12 healthy subjects were collected. Six different marker sets consisting of up to 26 markers and two clusters were simultaneously attached to the subjects’ lower limb and pelvis. The results show that particularly, the knee joint angles in the frontal and transverse plane showed the greatest differences between marker sets with in part contrary joint angle directions and great differences in angle magnitude. In addition, the amount of joint load was dependent on the marker set used for analysis. These results show that one must be careful when interpreting and comparing data of the frontal or transverse plane during high dynamic movements.

The size of the mammalian cerebrum spans more than 5 orders of magnitude. The smallest cerebrums have a smooth (lissencephalic) cortical surface, which gets increasingly folded (gyrencephalic) with cerebral size. Further, the proportion of white-to-gray matter volume increases with the total volume. These scaling relations have unusually little variation. Even though a number of theories and models have been proposed, it remains an open question, why this is so. Here, we show that almost all variance is explained by assuming a homogeneous composition of the cortex across mammals. On the basis of this assumption we derive quantitative analytical computational models. The first model predicts the cortical surface area from the gray and white matter volume. A single free parameter, for the height of cortical columns is estimated as λ = 2.9 mm (r2 = 0.996). The second model predicts the white matter volume as a function of the gray volume and the cerebral size (with parameters for intra- and extra-gyral connections lint, lext; ). The models are validated by predicting the effective cortical thickness and the folding parameter κ. The results accurately predict the human intraspecific variation of the surface relations. As expected, we find a reduced λ for cetaceans, and that preterm human infants do not follow the model. We also find deviations of gray and white matter volume for large cerebrums. Overall, the models thus show how the regular architecture of the cortex shapes the cerebrum. We conclude that the mammalian cerebrum scales in an isomorphic, rather than isometric, manner.

Background Lumbar multifidus (LM) is regarded as the major stabilizing muscle of the spine. The effects of exercise therapy in low back pain (LBP) are attributed to this muscle. A current literature review is warranted, however, given the complexity of LM morphology and the inconsistency of anatomical descriptions in the literature. Methods Scoping review of studies on LM morphology including major anatomy atlases. All relevant studies were searched in PubMed (Medline) and EMBASE until June 2019. Anatomy atlases were retrieved from multiple university libraries and online. All studies and atlases were screened for the following LM parameters: location, imaging methods, spine levels, muscle trajectory, muscle thickness, cross-sectional area, and diameter. The quality of the studies and atlases was also assessed using a five-item evaluation system. Results In all, 303 studies and 19 anatomy atlases were included in this review. In most studies, LM morphology was determined by MRI, ultrasound imaging, or drawings – particularly for levels L4–S1. In 153 studies, LM is described as a superficial muscle only, in 72 studies as a deep muscle only, and in 35 studies as both superficial and deep. Anatomy atlases predominantly depict LM as a deep muscle covered by the erector spinae and thoracolumbar fascia. About 42% of the studies had high quality scores, with 39% having moderate scores and 19% having low scores. The quality of figures in anatomy atlases was ranked as high in one atlas, moderate in 15 atlases, and low in 3 atlases. Discussion Anatomical studies of LM exhibit inconsistent findings, describing its location as superficial (50%), deep (25%), or both (12%). This is in sharp contrast to anatomy atlases, which depict LM predominantly as deep muscle. Within the limitations of the self-developed quality-assessment tool, high-quality scores were identified in a majority of studies (42%), but in only one anatomy atlas. Conclusions We identified a lack of standardization in the depiction and description of LM morphology. This could affect the precise understanding of its role in background and therapy in LBP patients. Standardization of research methodology on LM morphology is recommended. Anatomy atlases should be updated on LM morphology.

Background Originally, the cranks of a handcycle were mounted with a 180° phase shift (asynchronous). However, as handcycling became more popular, the crank mode switched to a parallel mounting (synchronous) over the years. Differences between both modes have been investigated, however, not into great detail for propulsion technique or practice effects. Our aim is to compare both crank modes from a biomechanical and physiological perspective, hence considering force and power production as a cause of physiological outcome measures. This is done within a practice protocol, as it is expected that motor learning takes place in the early stages of handcycling in novices. Methods Twelve able-bodied male novices volunteered to take part. The experiment consisted of a pre-test, three practice sessions and a post-test, which was subsequently repeated for both crank modes in a counterbalanced manner. In each session the participants handcycled for 3 × 4 minutes on a leveled motorized treadmill at 1.94 m/s. Inbetween sessions were 2 days of rest. 3D forces, handlebar and crank angle were measured on the left hand side. Kinematic markers were placed on the handcycle to monitor the movement on the treadmill. Lastly, breath-by-breath spirometry combined with heart-rate were continuously measured. The effects of crank mode and practice-based learning were analyzed using a two way repeated measures ANOVA, with synchronous vs asynchronous and pre-test vs post-test as within-subject factors. Results In the pre-test, asynchronous handcycling was less efficient than synchronous handcycling in terms of physiological strain, force production and timing. At the post-test, the metabolic costs were comparable for both modes. The force production was, also after practice, more efficient in the synchronous mode. External power production, crank rotation velocity and the distance travelled back and forwards on the treadmill suggest that asynchronous handcycling is more constant throughout the cycle. Conclusions As the metabolic costs were reduced in the asynchronous mode, we would advise to include a practice period, when comparing both modes in scientific experiments. For handcycle users, we would currently advise a synchronous set-up for daily use, as the force production is more effective in the synchronous mode, even after practice.

Although acute aerobic exercise benefits different aspects of emotional functioning, it is unclear how exercise influences the processing of emotional stimuli and which brain mechanisms support this relationship. We assessed the influence of acute aerobic exercise on valence biases (preferential processing of negative/positive pictures) by performing source reconstructions of participants’ brain activity after they viewed emotional scenes. Twenty-four healthy participants (12 women) were tested in a randomized and counterbalanced design that consisted of three experimental protocols, each lasting 30 min: low-intensity exercise (Low-Int); moderate-intensity exercise (Mod-Int); and a seated rest condition (REST). After each of the protocols, participants viewed negative and positive pictures, during which event-related magnetic fields were recorded. Analyses revealed that exercise strongly impacted the valence processing of emotional scenes within a widely distributed left hemispheric spatio-temporal cluster between 190 and 310 ms after picture onset. Brain activity in this cluster showed that a negativity bias at REST (negative > positive picture processing) diminished after the Low-Int condition (positive = negative) and even reversed to a positivity bias after the Mod-Int condition (positive > negative). Thus, acute aerobic exercise of low and moderate intensities induces a positivity bias which is reflected in early, automatic processes.

textabstractWe present two methods based on functional principal component analysis (FPCA) for the estimation of smooth derivatives of a sample of random functions, which are observed in a more than one-dimensional domain.We apply eigenvalue decomposition to a) the dual covariance matrix of the derivatives, and b) the dual covariance matrix of the observed curves. To handle noisy data from discrete observations, we rely on local polynomial regressions. If curves are contained in a finite-dimensional function space, the secondmethod performs better asymptotically. We apply our methodology in a simulation and empirical study, inwhichwe estimate state price density (SPD) surfaces from call option prices.We identify three main components, which can be interpreted as volatility, skewness and tail factors.We also find evidence for term structure variation.

Free, 3-D interceptive movements are difficult to visualize and quantify. For ball catching, the endpoint of a movement can be anywhere along the target's trajectory. Furthermore, the hand may already have begun to move before the subject has estimated the target's trajectory, and the subject may alter the targeted position during the initial part of the movement. We introduce a method to deal with these difficulties and to quantify three movement phases involved in catching: the initial, non-goal-directed phase; the goal-directed phase, which is smoothly directed toward the target's trajectory; and the final, interception phase. Therefore, the 3-D movement of the hand was decomposed into a component toward the target's trajectory (the minimal distance of the hand to the target's parabolic [MDHP] trajectory) and a component along this trajectory. To identify the goal-directed phase of the MDHP trajectory, we employed the empirical finding that goal-directed trajectories are minimally jerky. The second component, along the target's trajectory, was used to analyze the interaction of the hand with the ball. The method was applied to two conditions of a ball-catching task. In the manipulated condition, the initial part of the ball's flight was occluded, so the visibility of the ball was postponed. As expected, the onset of the smooth part of the movement shifted to a later time. This method can be used to quantify anticipatory behavior in interceptive tasks, allowing researchers to gain new insights into movement planning toward the target's trajectory.

Down syndrome (DS) is one of the most common chromosomal disorders and is often associated with a number of motor and cognitive impairments. Little research has been dedicated to investigating the perceptual abilities of individuals with DS. The visual processing of biological motion has been shown to be impaired in DS. It has been proposed that these impairments may stem from an inability to process the global patterns of full-body motion produced by a moving actor; however, this has not been explicitly investigated. We tested groups of participants with and without DS on a task requiring the visual discrimination of point-light walkers from spatially scrambled versions of point-light walkers. Participants with DS demonstrated poorer performance and slower reaction times on the task than healthy controls. From these results, we conclude that biological motion processing is impaired in DS and that this deficit is related to an inability to integrate global configural cues. In a second experiment, individuals with DS were able to discriminate the direction in which laterally translating walkers moved, suggesting that the global motion processing deficit observed in Experiment 1 is specific to biological motion recognition and does not generalise to other types of global motion.

The Arctic represents an extreme habitat for phototrophic algae due to long periods of darkness caused by the polar night (~4 months darkness). Benthic diatoms, which dominate microphytobenthic communities in shallow water regions, can survive this dark period, but the underlying physiological and biochemical mechanisms are not well understood. One of the potential mechanisms for long-term dark survival is the utilisation of stored energy products in combination with a reduced basic metabolism. In recent years, water temperatures in the Arctic increased due to an ongoing global warming. Higher temperatures could enhance the cellular energy requirements for the maintenance metabolism during darkness and, therefore, accelerate the consumption of lipid reserves. In this study, we investigated the macromolecular ratios and the lipid content and composition of Navicula cf. perminuta Grunow, an Arctic benthic diatom isolated from the microphytobenthos of Adventfjorden (Svalbard, Norway), over a dark period of 8 weeks at two different temperatures (0 and 7 °C). The results demonstrate that N. perminuta uses the stored lipid compound triacylglycerol (TAG) during prolonged dark periods, but also the pool of free fatty acids (FFA). Under the enhanced temperature of 7 °C, the lipid resources were used significantly faster than at 0 °C, which could consequently lead to a depletion of this energy reserves before the end of the polar night. On the other hand, the membrane building phospho- and glycolipids remained unchanged during the 8 weeks darkness, indicating still intact thylakoid membranes. These results explain the shorter survival times of polar diatoms with increasing water temperatures during prolonged dark periods.

We derive a mechanical model of human motion where an elderly person decides to step over an obstacle rather than avoiding it. Such a decision may be deliberate or \ud forced due to a sudden appearing obstacle in his/her way. The model is represented by a nonautonomous system of ordinary differential equations with discontinuous right hand side. We provide a notion of lateral stability. It is shown that increasing the angle between legs increases stability linearly. This implies that an individual reduces the risk of falling due to stepping over an obstacle by increasing the angle between legs.