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Psoriasis is an inflammatory skin disease characterized by keratinocyte proliferation and inflammatory cell infiltration induced by IL-17. However, the molecular mechanism through which IL-17 signaling in keratinocytes triggers skin inflammation remains not fully understood. Pyruvate kinase M2 (PKM2), a glycolytic enzyme, has been shown to have non-metabolic functions. Here, we report that PKM2 mediates IL-17A signaling in keratinocytes triggering skin psoriatic inflammation. We find high expression of PKM2 in the epidermis of psoriatic patients and mice undergoing psoriasis models. Specific depletion of PKM2 in keratinocytes attenuates the development of experimental psoriasis by reducing the production of pro-inflammatory mediators. Mechanistically, PKM2 forms a complex with Act1 and TRAF6 regulating NF-κB transcriptional signaling downstream of the IL-17 receptor. As IL-17 also induces PKM2 expression in keratinocytes, our findings reveal a sustained signaling circuit critical for the psoriasis-driving effects of IL-17A, suggesting that PKM2 is a potential therapeutic target for psoriasis.

Sulfur deficiency in soils has become an increasing concern over the past decades. Despite elemental sulfur (S8) vast utilization as a commercial fertilizer, S8 has to be biologically oxidized for plant assimilation, drastically limiting its efficiency. Therefore, we propose a new fertilizer in which S8 structure is more accessible to oxidizing microorganisms by chemical modification via inverse vulcanization technique, a solvent-free copolymerization method, with soybean oil as comonomer. Sulfur oxidation experiments were performed by A. niger submerged cultivation, confirming that the homogeneous rubbery-like material provides enhanced oxidation, with great potential as multifunctional sulfur-fertilizer.

Shape perception is crucial for object recognition. However, it remains unknown exactly how shape information is represented and used by the visual system. Here, we tested the hypothesis that the visual system represents object shape via a skeletal structure. Using functional magnetic resonance imaging (fMRI) and representational similarity analysis (RSA), we found that a model of skeletal similarity explained significant unique variance in the response profiles of V3 and LO. Moreover, the skeletal model remained predictive in these regions even when controlling for other models of visual similarity that approximate low-to high-level visual features (i.e., Gabor-jet, GIST, HMAX, and AlexNet), and across different surface forms, a manipulation that altered object contours while preserving the underlying skeleton. Together, these findings shed light on shape processing in human vision, as well as the computational properties of V3 and LO. We discuss how these regions may support two putative roles of shape skeletons: namely, perceptual organization and object recognition.

To navigate the world, human adults rely on various types of geometric cues. Yet there is debate over which cues young children use to guide reorientation. Some researchers have argued that particular geometric cues, such as distance, are privileged with respect to navigation, at least early in human ontogeny. On this view, children rely exclusively on distance to regain their orientation. Other geometric cues, such as length, are used for object recognition or two-dimensional form analysis, not reorientation. Here we show that children are capable of using multiple Euclidean cues to reorient, but their ability to use these cues can be masked by global shape information. We argue that children are flexible in their use of geometric cues for reorientation, using both distance and length cues. The role of global shape in facilitating or impeding reorientation is discussed.

Visual displays of objects include information about number and other magnitudes such as cumulative surface area. Despite the confluence of cues, a prevalent view is that number is uniquely salient within multidimensional stimuli. Consistent with this view, Tomlinson et al. (2020) report that, in addition to greater acuity for number than area among both children and adults, number biases area judgments more than the reverse, at least in childhood. However, a failure to consider perceived area, undermines these results. To address this concern, we used an index of perceived area when assessing acuity and bias of number and area. In this context, number and area were comparable in acuity among children and adults. Bias, however, differed across development. Although adults showed greater bias of number on area judgments than the reverse, children experienced greater area bias on number judgments. Thus, contra Tomlinson et al., when differences in mathematical and perceived area are accounted for, area is more salient than number early in development. However, number does become the more salient dimension by adulthood, suggesting a role for experience with symbolic number and education in directing attention towards number within multidimensional visual stimuli.

Spatial-numerical associations have been found across different studies, yet the basis for these associations remains debated. The current study employed an order judgment task to adjudicate between two competing accounts of such associations, namely the Mental Number Line (MNL) and Working Memory (WM) models. On this task, participants judged whether number pairs were in ascending or descending order. Whereas the MNL model predicts that ascending and descending orders should map onto opposite sides of space, the WM model predicts no such mapping. Moreover, we compared the spatial-order mapping for numerical and non-numerical sequences because the WM model predicts no difference in mapping. Across two experiments, we found consistent spatial mappings for numerical order along both horizontal and vertical axes, consistent with a MNL model. In contrast, we found no consistent mappings for letter sequences. These findings are discussed in the context of conflicting extant data related to these two models.

Polyurethanes have been widely used in a wide variety of applications that benefit our everyday life. However, in the present scenario, it is urgent to find solutions towards more sustainable polymeric systems that can be more biodegradable and less dependent on non-renewable feedstocks. The present work proposes a thorough structural investigation of polyurethane materials based on the use of two small eco-friendly reactants: glycerol and urea. The results with glycerol demonstrated a preferential reactivity of MDI with primary alcohol terminals, except when the diisocyanate was in excess, which resulted in crosslinking formation (shown in 13C NMR). Urea-based materials displayed superior thermal stability, associated with higher crystallinity and intermolecular forces, as observed in TGA, XRD, and FTIR. Overall, the structural characteristics support the potential of biodegradability of the studied polyurethanes and polyureas.

This study concerns the links between analog representations of spatial extent and visuospatial geometric competence in childhood. Research with college students suggests that individual differences in adults' ability to approximate cumulative surface area are reflected in their knowledge of school-relevant geometry. Other research suggests that the link between analog magnitude representations and mathematical reasoning may be present earlier in development, at least for representations of numerical magnitude and arithmetic concepts. Here we asked whether the understanding of basic geometric concepts and transformations, such as parallelism and mental rotation, makes similar psychological connections to spatial magnitude, particularly representations of area, prior to extensive education with geometry. We found that the precision with which 4- to 6-year-olds approximate area for irregular 2D shapes positively correlated with their performance on a basic geometry test, even when controlling for age and verbal intelligence. This finding points to a previously undocumented relationship between a system for representing analog magnitude and geometric competence. The potential interactions with systems of object recognition and navigation are discussed.

Much evidence suggests that common posterior parietal mechanisms underlie the orientation of attention in physical space and along the mental number line. For example, the small leftward bias (pseudoneglect) found in paper-and-pencil line bisection is also found when participants "bisect" number pairs, estimating (without calculating) the number midway between two others. For bisection of physical lines, pseudoneglect has been found to shift rightward as lines are moved from near space (immediately surrounding the body) to far space. We investigated whether the presentation of stimuli in near or far space also modulated spatial attention for the mental number line. Participants bisected physical lines or number pairs presented at four distances (60, 120, 180, 240cm). Clear rightward shifts in bias were observed for both tasks. Furthermore, the rate at which this shift occurred in the two tasks, as measured by least-squares regression slopes, was significantly correlated across participants, suggesting that the transition from near to far distances induced a common modulation of lateral attention in physical and numerical space. These results demonstrate a tight coupling between number and physical space, and show that even such prototypically abstract concepts as number are modulated by our on-line interactions with the world.

It has been suggested that young children can only reorient, locating a target object, when the geometry of an enclosed space provides distinctive shape information [e.g., Hermer, L., & Spelke, E. (1994). A geometric process for spatial reorientation in young children. Nature, 370, 57–59]. Recently, however, young children were shown to specify location in a square-shaped space, where geometry is uninformative, so long as scale-like information was available on the walls of the space [Huttenlocher, J., & Lourenco, S. F. (2007a). Coding location in enclosed spaces: Is geometry the principle? Developmental Science, 10, 741–746]. Here we build on this work by examining more closely what types of cues afford 18- to 24-month-olds an advantage in locating a target object following disorientation. Their performance was assessed when linear scale-like information was presented either in isolation or in composite form. It was found that, even in isolation, young children searched at the appropriate locations, with added benefit when presented as a composite. We suggest that linear scale-like dimensions, especially when available in composite form, play a critical role in supporting location representation in young children.

The distinction between near space and the space farther away has been well established, as has the relation of this distinction to arm length. Recent studies provide evidence for the plasticity of near space, showing that it is possible to expand its extent ("size") through tool-use. In the present study, we examine the converse effect, whether contraction of near space results from increasing the effort involved on a line bisection task. Adult participants bisected lines at different distances, while, in some cases, wearing weights. In Experiment 1, the arms, specifically, were weighted (wrist weights), and in Experiment 2, more general body weights were used (heavy backpack). As in previous studies, unencumbered participants showed leftward bias when bisecting lines at the closest distances and a rightward shift in bias with increasingly farther distances. With wrist weights, but not a heavy backpack, participants showed more rightward bias at the closest distances, and a more gradual rightward shift with increasing distance, as if the nearest locations were represented as being farther away. These results suggest that increased effort, when specifically related to the arm, can serve to reduce the size of near space, providing support for the generally symmetrical plasticity of near space representations.

Many researchers have proposed that the near space immediately surrounding the body is represented differently than more distant space. Indeed, it has often been suggested that near space encompasses that within arm's reach. The present study used a line bisection task in healthy adults to investigate the effects of tool use on space perception, and the nature of the transition between near and far space. Subjects bisected lines at four distances controlled for both veridical and angular size using a laser pointer and a set of sticks. When the laser pointer was used, a left to right shift in bias was observed as stimuli were moved from near to far space. When a tool was used, however, a leftward bias was observed at all distances, similar to that observed with the laser pointer in near space. These results suggest that the tool expanded the range of near space. Additionally, the transition from near to far space was gradual, with no abrupt shift at arm's length (or at any other distance). In contrast to theories describing near space as that within arm's reach, these findings suggest that the representation of near space is less rigid, extending with tool use and gradually transitioning into far space.

In this paper, we take up Kessens challenge to develop a philosophically and historically informed developmental theory by describing a theory of the understanding and use of representations that draws heavily on the hermeneutics of Paul Ricoeur and the genetic epistemology of James Mark Baldwin. This theory, which construes representation to be intrinsically mimetic, characterizes the development of representational understanding as internalization (cf. Vygotsky, 1978), and emphasizes the importance of self-reflection and psychological distancing for the decontextualization of representations from the circumstances in which they were created. Selfreflection is described in terms of a process model of recursive consciousness, the Levels of Consciousness Model (Zelazo, 1999, 2000; Zelazo & Zelazo, 1998).

The present study focuses on interlimb coordination in walking with an above-knee prosthesis using concepts and tools of dynamical systems theory (DST). Prosthetic walkers are an interesting group to investigate from this theory because their locomotory system is inherently asymmetric, while, according to DST, coordinative stability may be expected to be reduced as a function of the asymmetry of the oscillating components. Furthermore, previous work on locomotion motivated from DST has shown that the stability of interlimb coordination increases with walking velocity, leading to the additional expectation that the anticipated destabilizing effect of the prosthesis-induced asymmetry may be diminished at higher walking velocities. To examine these expectations, an experiment was conducted aimed at comparing interlimb coordination during treadmill walking between seven participants with an above-knee prosthesis and seven controls across a range of walking velocities. The observed gait patterns were analyzed in terms of standard gait measures (i.e., absolute and relative swing, stance and step times) and interlimb coordination measures (i.e., relative phase and frequency locking). As expected, the asymmetry brought about by the prosthesis led to a decrease in the stability of the coordination between the legs as compared to the control group, while coordinative stability increased with increasing walking velocity in both groups in the absence of a significant interaction. In addition, the 2:1 frequency coordination between arm and leg movements that is generally observed in healthy walkers at low walking velocities was absent in the prosthetic walkers. Collectively, these results suggest that both stability and adaptability of coordination are reduced in prosthetic walkers but may be enhanced by training them to walk at higher velocities.