One of the long-standing arguments about the evolution of bipedality centers on the locomotor pattern used by the last common ancestor (LCA) of apes and humans. In particular, knuckle-walking has been suggested as this locomotor pattern on the basis of shared morphology in the upper limb between African apes and ...

A type Ia supernova is thought to begin with the explosion of a white dwarf star. The explosion could be triggered by the merger of two white dwarfs (a 'double-degenerate' origin), or by mass transfer from a companion star (the 'single-degenerate' path). The identity of the progenitor is still controversial; ...

BackgroundAltered neuromuscular control due to compromised joint position sense may contribute to recurrent shoulder instability.ObjectiveThe purpose of the present study was to examine whether individuals with anterior shoulder instability exhibit larger shoulder position sense errors than subjects with healthy shoulders in both passive matching and active positioning.DesignThis was a between-groups ...

In habitats where prey is either rare or difficult to predict spatiotemporally, such as open habitats, predators must be adapted to react effectively to variations in prey abundance. Open-habitat foraging bats have a wing morphology adapted for covering long distances, possibly use information transfer to locate patches of high prey ...

Networks of polymerizing actin filaments can propel intracellular pathogens and drive movement of artificial particles in reconstituted systems. While biochemical mechanisms activating actin network assembly have been well characterized, it remains unclear how particle geometry and large-scale force balance affect emergent properties of movement. We reconstituted actin-based motility using ellipsoidal ...

Bipolar cells are the central neurons of the retina that convey visual signals from rod and cone photoreceptors in the outer retina to higher-order neurons in the inner retina and the brain. Early anatomical studies have suggested that there are 4 types of cone hyperpolarizing (OFF) bipolar cells (HBCs) in ...

Among other cues, the visual system uses shading to infer the 3D shape of objects. The shading pattern depends on the illumination and reflectance properties (BRDF). In this study, we compared 3D shape perception between identical shapes with different BRDFs. The stimuli were photographed 3D printed random smooth shapes that ...

Derived sabercats had craniomandibular morphologies that in many respects were highly different from those of extant felids, and this has often been interpreted functionally as adaptations for predation at extreme gape angles with hypertrophied upper canines. It is unknown how much of this was a result of intraspecific postnatal ontogeny, ...

After viewing a colored figure on a uniform gray background, an observer will see a negative afterimage after the colored figure disappears. This study shows that the shapes of afterimages vary systematically according to the shape of the adaptation stimuli, a phenomenon that could be caused only by cortical shape ...

Light and dark are used pervasively to represent positive and negative concepts. Recent studies suggest that black and white stimuli are automatically associated with negativity and positivity. However, structural factors in experimental designs, such as the shared opposition in the valence (good vs. bad) and brightness (light vs. dark) dimensions ...

Reason for performing the study: To identify potential functional-anatomical characteristics of the cranial horn attachment of the medial meniscus (MM) that may help explain the pathogenesis of the common tear patterns that have been reported. Hypothesis: Full extension of the stifle generates a significant increase in tensile forces within the ...

To study the formation of the photosynthetic apparatus in nature, the carotenoid and chlorophyllous pigment compositions of differently developed leaf primordia in closed and opening buds of common ash (Fraxinus excelsior L.) and horse chestnut (Aesculus hippocastanum L.) as well as in closed buds of tree of heaven (Ailanthus altissima ...

Detecting motion is a feature of all advanced visual systems [1], nowhere more so than in flying animals, like insects [2, 3]. In flies, an influential autocorrelation model for motion detection, the elementary motion detector circuit (EMD; [4, 5]), compares visual signals from neighboring photoreceptors to derive information on motion direction and ...

The operation of photovoltaic (PV) tweezers, using the evanescent light-induced PV fields to trap and pattern nano- and micro-meter particles on a LiNbO₃ crystal surface, is discussed. The case of a periodic light pattern is addressed in detail, including the role of particle shape and the modulation index of the ...

Kinesin-5 motors fulfil essential roles in mitotic spindle morphogenesis and dynamics as slow, processive microtubule (MT) plus-end directed motors. The Saccharomyces cerevisiae kinesin-5 Cin8 was found, surprisingly, to switch directionality. Here, we have examined directionality using single-molecule fluorescence motility assays and live-cell microscopy. On spindles, Cin8 motors mostly moved slowly ...

Light-evoked responses of 106 morphologically-identified narrow-field amacrine cells (ACs) were studied in dark-adapted mouse retinal slices. 45 cells exhibit AIIAC morphology, 55% of which show characteristic AIIAC physiological properties (AIIACs) and the remaining 45% display different physiological responses, suggesting that AIIACs are functionally heterogeneous. Moreover, we found that 42 cells ...

Two wild type substrains of a motile cyanobacterium Synechocystis sp. PCC 6803 show positive phototaxis toward a light source (PCC-P) and negative phototaxis away from light (PCC-N). In this study, we found that a novel two-component system of photoresponse is involved in the phototactic regulation. Inactivation of slr1212 (pixA), which ...

In a recent publication using an actin-visualized line of Arabidopsis (Ichikawa et al. 2011, ref. 11), we reported a detailed analysis with higher time resolution on the dynamics of chloroplast actin filaments (cp-actin filaments) during chloroplast avoidance movement and demonstrated a good correlation between the biased configuration of cp-actin filaments ...

Bipedalism has long been recognized as the seminal adaptation of the hominin radiation and thus used to distinguish hominins from great ape fossils. Notwithstanding preconceptions and varied interpretations, the distinctive features of the modern human foot and accompanying striding gait, appear to be recent innovations that are largely absent in ...

There has long been interest in the influence of predators on prey populations, although most predator-prey studies have focused on prey species that are targets of directed predator searching. Conversely, few have addressed depredation that occurs after incidental encounters with predators. We tested two predictions stemming from the hypothesis that ...

The elasticity and nanomechanical response of Aspergillus niger spores determined using atomic force microscopy (AFM) and nanoindentation are discussed. The force-displacement curve of the spore surfaces shows that the average surface roughness of spores was approximately 33nm and that the adhesion force ranged from 9 to 28nN. The Young's modulus ...

Persistent photoconductance, a prolonged light-induced conducting behavior that lasts several hundred seconds, has been observed in semiconductors. Here we report persistent negative photoconductance and consecutive prominent persistent positive photoconductance in graphene. Unusually large yields of negative PC (34%) and positive PC (1652%), and remarkably long negative transient response time (several ...

This is a feature issue devoted to optical phenomena that can be observed in nature, primarily with the naked eye. Many of the papers published in this feature issue are based on presentations given at the "Light & Color in Nature" conference held in June 2010 at St. Mary's College ...

Orientational behaviours under the action of linearly polarized light and circularly polarized light of a side-chain azobenzene containing polymer were studied by conoscopic polarized microscopy. The results suggest that the linearly polarized light (473 nm, 20 mW cm(-2) ) results in an in-plane orientation of the azobenzene groups. The irradiation ...

Abstract We describe a new technique for visualizing proanthocyanidin-containing elements in plant tissues. Our innovation is the fixation of condensed tannins with an exogenous protein prior to alcohol dehydration. In this way, tannins do not undergo partial solubilization during the dehydration sequence and appear as sharply contoured globules of various ...

The question of the arbitrariness of language is among the oldest in cognitive sciences, and it relates to the nature of the associations between vocal sounds and their meaning. Growing evidence seems to support sound symbolism, claiming for a naturally constrained mapping of meaning into sounds. Most of such evidence, ...

A simple light microscopic technique was developed in order to quantify the damage inflicted by high-power low-frequency ultrasound (0-160W, 20kHz) treatment on potato starch granules in aqueous dispersions. The surface properties of the starch granules were modified using ethanol and SDS washing methods, which are known to displace proteins and ...

ABSTRACT. Meglitschia mylei n. sp. found in the gall bladder of the teleostean fish Myleus rubripinnis (Serrasalmidae) from the middle Amazonian region of Brazil is described using light and transmission electron microscopy. The spores observed in the bile averaged 24.6±0.8 μm long, 8.7±0.4 μm wide and 5.1±0.3 μm thick and were strongly furcate ...

Dexterous use of the hand represents a sophisticated sensorimotor function. In behaviors such as playing the piano, it can involve strong temporal and spatial constraints. The purpose of this study was to determine fundamental patterns of covariation of motion across joints and digits of the human hand. Joint motion was ...

The current picture of galaxy evolution advocates co-evolution of galaxies and their nuclear massive black holes, through accretion and galactic merging. Pairs of quasars, each with a massive black hole at the centre of its galaxy, have separations of 6,000 to 300,000 light years (refs 2 and 3; 1 parsec = ...

In order to obtain an improved understanding of the assembly of the bacterial photosynthetic apparatus, we have conducted a proteomic analysis of pigment-protein complexes isolated from the purple bacterium Rhodobacter sphaeroides undergoing acclimation to reduced incident light intensity. Photoheterotrophically growing cells were shifted from 1,100 to 100 W/m(2) and intracytoplasmic membrane ...

Allocating attention to basic features such as colour enhances perception of the respective features throughout the visual field. We have previously shown that feature-based attention also plays a role for more complex features required for object perception. To investigate at which level object perception is modulated by feature-based attention we ...

1. Nest predation limits avian fitness, so birds should favour nest sites that minimize predation risk. Nevertheless, preferred nest microhabitat features are often uncorrelated with apparent variation in predation rates. 2. This lack of congruence between theory-based expectation and empirical data may arise when birds already occupy 'adaptive peaks'. If birds nest ...

We report the results of an experiment designed to elucidate the extent to which the error related ERP components are affected by response and stimulus similarity. We examined the ERPs under varying degrees of mismatch between the representations of actual and appropriate responses. We replicated the design used in an ...

The purpose of this study was to compare control of force and modulation of agonist muscle activity of young and older adults when the amount of visual feedback was varied at two different force levels. Ten young adults (25 years ± 4 years, 5 men and 5 women) and ten older adults (71 years ± 5 years, 4 men ...

Whether and in what way enumeration processes differ for small and large sets of objects is still a matter of debate. In order to shed light on this issue, EEG data were obtained from 60 normally developing elementary school children. Adopting a standard non-symbolic numerical comparison paradigm allowed us to ...

OBJECTIVES: The goal of this study was to investigate the effect of visual acuity on the anticipatory (APAs) and compensatory (CPAs) components of postural control. METHODS: Ten individuals participated in the experiments involving perturbations induced by a pendulum while their visual acuity was altered. The different visual acuity conditions were ...

Emotion modulates our time perception. So far, the relationship between emotion and time perception has been examined with visible emotional stimuli. The present study investigated whether invisible emotional stimuli affected time perception. Using continuous flash suppression, which is a kind of dynamic interocular masking, supra-threshold emotional pictures were masked or ...

Chloroplasts change their positions in a cell in response to light intensities. The photoreceptors involved in chloroplast photo-relocation movements and the behavior of chloroplasts during their migration were identified in our previous studies, but the mechanism of movement has yet to be clarified. In this study, the behavior of actin ...

The phototropin-dependent intracellular relocation of chloroplasts is a ubiquitous phenomenon in plants. We have previously revealed the involvement of a short cp-actin (chloroplast actin) filament-based mechanism in this movement. Here, the reorganization of cp-actin filaments during the avoidance movement of chloroplasts was analyzed in higher time resolution under blue GFP ...

In the multiple object tracking (MOT) task, observers can typically keep track of up to four moving objects. Little is known however about the extent to which object motion is used by observers during MOT. For example, direction and speed might be used to anticipate future positions. We here ask ...

We currently have little understanding of how birds know what nest to build and what little we do know has been gained largely from investigations of the completed structures (morphology of finished nests) or of material selection. Here we looked at the behaviours performed by male Southern Masked weaverbirds when ...

This study deals with the influence of surface roughness on the color of resin composites. Ten resin composites (microfilled, hybrid, and microhybrid) were each polished with 500-grit, 1200-grit, 2000-grit, and 4000-grit SiC papers. The roughness parameter (R(a)) was measured using a Plμ confocal microscope, and field-emission scanning electron microscope (Fe-SEM) ...

The renal diseases most frequently associated with myeloma include amyloidosis, monoclonal immunoglobulin deposition disease, and cast nephropathy. Less frequently reported is light chain proximal tubulopathy, a disease characterized by κ-restricted crystal deposits in the proximal tubule cytoplasm. Light chain proximal tubulopathy without crystal deposition is only loosely related to the ...

The microtubule-based metaphase spindle is subjected to forces that act in diverse orientations and over a wide range of timescales. Currently, we cannot explain how this dynamic structure generates and responds to forces while maintaining overall stability, as we have a poor understanding of its micromechanical properties. Here, we combine ...

Length adaptation in airway smooth muscle (ASM) is attributed to reorganization of the cytoskeleton, and in particular the contractile elements. However, a constantly changing lung volume with tidal breathing (hence changing ASM length) is likely to restrict full adaptation of ASM for force generation. There is likely to be continuous ...

The temporal evolution of the spatially periodic electroconvection (EC) patterns has been studied within the period of the driving ac voltage by monitoring the light intensity diffracted from the pattern. Measurements have been carried out on a variety of nematic systems, including those with negative dielectric and positive conductivity anisotropy, ...

We investigate the forces exerted on embedded inclusions by a fluid medium with long-range correlations, described by an effective scalar field theory. Such forces are the basis for the medium-mediated Casimir-like force. To study these forces beyond thermal average, it is necessary to define them in each microstate of the ...

Kinematic analyses of mandibular movement in humans demonstrate that the mandibular instantaneous center of rotation (ICoR) is commonly located near the level of the occlusal plane and varies in its position during a chewing sequence. Few data are available regarding the location of the ICoR in nonhuman primates and it ...

Purpose: Posterior capsule opacification (PCO) degrades visual function by reducing visual acuity, but also by increasing intra-ocular light-scatter. We used an in-vitro model to elucidate the effect of PCO-morphology on light-scatter and its functional aspect, as can be assessed with straylight measurement. Methods: Forward PCO-scatter by opacified capsular bags was ...