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In this study, undulations and their influence on the longitudinal compressive strength of a unidirectional glass fiber reinforced polymer (GFRP) composite are investigated theoretically and experimentally. The objective of this research is to explore the failure mechanisms in FRP and to characterize the mechanical properties of FRP as a function of fiber orientation. For this purpose, a multiscale material model is developed that considers a stochastic fiber orientation distribution (FOD) and models matrix fracture-initiated failure. The relationship between compressive strength and undulation is investigated experimentally on standardized specimens made of unidirectional GFRP. The fiber orientations are measured using X-ray computed tomography and ImageJ image analysis, resulting in a binormal distribution of fiber orientations in the series of samples tested. To examine the failure process in detail, the compression tests are simulated using finite element analysis (FEA). Both the FEA results and the measured compressive strengths confirm the model assumption of matrix fracture-initiated failure under longitudinal compressive loading. The presented analytical model realistically represents the correlation of compressive strength with the FOD.

In this work, we consider the integrated problem of locomotive scheduling and driver assignment in rail freight companies. Our aim is to compute an optimal simultaneous assignment of locomotives and drivers to the trains listed in a given order-book. Mathematically, this leads to the combination of a set-packing problem with compatibility constraints and a multi-commodity-flow problem. We develop a binary-programming formulation to model the given task and improve it by performing a clique-based tightening of the original set-packing inequalities. The objective function of this model makes sure that as many trains as possible are running. To handle the computational complexity of the problem, we introduce a novel decomposition approach which decomposes the problem into a master locomotive scheduling problem and a subproblem for driver assignment. It exploits the fact that the master problem is empirically much easier to solve than the subproblem. For any fixed solution of the master problem, we can use the subproblem to either confirm feasibility of the master solution or to derive valid inequalities from various constraint classes to cut the infeasible master solution off and reiterate. To further improve solution times, we also develop a presolve heuristic. We demonstrate the potential of the presented method by solving a large-scale real-world problem instance provided by our industry partner DB Cargo Polska S.A., as well as a set of derived realistic instances.

Malignant transformation of human cells is associated with their re-programming which results in uncontrolled proliferation and in the same time biochemical activation of immunosuppressive pathways which form cancer immune evasion machinery. However, there is no conceptual understanding of whether immune evasion machinery pathways and expression of immune checkpoint proteins form a part of the process of malignant transformation or if they are triggered by T lymphocytes and natural killers (NK) attempting to attack cells which are undergoing or already underwent malignant transformation. To address this fundamental question, we performed experimental malignant transformation of BEAS-2B human bronchial epithelium cells and RC-124 non-malignant human kidney epithelial cells using bracken extracts containing carcinogenic alkaloid called ptaquiloside. This transformation led to a significant upregulation of cell proliferation velocity and in the same time led to a significant upregulation in expression of key immune checkpoint proteins – galectin-9, programmed death ligand 1 (PD-L1), indoleamine 2,3-dioxygenase (IDO1). Their increased expression levels were in line with upregulation of the levels and activities of HIF-1 transcription complex and transforming growth factor beta type 1 (TGF-β)-Smad3 signalling pathway. When co-cultured with T cells, transformed epithelial cells displayed much higher and more efficient immune evasion activity compared to original non-transformed cells. Therefore, this work resolved a very important scientific and clinical question and suggested that cancer immune evasion machinery is activated during malignant transformation of human cells regardless the presence of immune cells in microenvironment.

Elastane, also known as spandex, is a synthetic polymer fibre based on polyurethane, which is present in low amounts in numerous textile products. It is used frequently particularly in sportswear and underwear, because of its stretchability and body-shaping properties. The currently commonly-used standardized elastane quantification method has many outstanding disadvantages, however ongoing production processes as well as upcoming recycling processes rely on it. This study presents a faster, more reliable and more eco-friendly tool to detect and quantify elastane in textiles using differential scanning calorimetry (DSC). An elastane quantification tool (EQT) was developed by studying eleven different elastane samples available on the textile market. The fundament of the EQT is a polymer specific phenomenon, which is investigated in detail by spectroscopic (ATR-FTIR) and thermal (thermogravimetric analysis, DSC) analyses. Ten different textile waste samples from the manufacturing industry and waste collection were selected to test the EQT. Obtained results are very promising, as the elastane contents could be determined quickly and accurately. The EQT has the potential to become a widely used method in the textile production chain, particularly in the upcoming recycling sector.

Face and body orientation convey important information for us to understand other people's actions, intentions and social interactions. It has been shown that several occipitotemporal areas respond differently to faces or bodies of different orientations. However, whether face and body orientation are processed by partially overlapping or completely separate brain networks remains unclear, as the neural coding of face and body orientation is often investigated separately. Here, we recorded participants’ brain activity using fMRI while they viewed faces and bodies shown from three different orientations, while attending to either orientation or identity information. Using multivoxel pattern analysis we investigated which brain regions process face and body orientation respectively, and which regions encode both face and body orientation in a stimulus-independent manner. We found that patterns of neural responses evoked by different stimulus orientations in the occipital face area, extrastriate body area, lateral occipital complex and right early visual cortex could generalise across faces and bodies, suggesting a stimulus-independent encoding of person orientation in occipitotemporal cortex. This finding was consistent across functionally defined regions of interest and a whole-brain searchlight approach. The fusiform face area responded to face but not body orientation, suggesting that orientation responses in this area are face-specific. Moreover, neural responses to orientation were remarkably consistent regardless of whether participants attended to the orientation of faces and bodies or not. Together, these results demonstrate that face and body orientation are processed in a partially overlapping brain network, with a stimulus-independent neural code for face and body orientation in occipitotemporal cortex.

Summary: Substantial research efforts have gone into elucidating the role of protein misfolding and self-assembly in the onset and progression of Alzheimer’s disease (AD). Aggregation of the Amyloid-β (Aβ) peptide into insoluble fibrils is closely associated with AD. Here, we use biophysical techniques to study a peptide-based approach to target Aβ amyloid aggregation. A peptide construct, NCAM-PrP, consists of a largely hydrophobic signal sequence linked to a positively charged hexapeptide. The NCAM-PrP peptide inhibits Aβ amyloid formation by forming aggregates which are unavailable for further amyloid aggregation. In a membrane-mimetic environment, Aβ and NCAM-PrP form specific heterooligomeric complexes, which are of lower aggregation states compared to Aβ homooligomers. The Aβ:NCAM-PrP interaction appears to take place on different aggregation states depending on the absence or presence of a membrane-mimicking environment. These insights can be useful for the development of potential future therapeutic strategies targeting Aβ at several aggregation states.

It has been shown that human faces are processed holistically (i.e. as indecomposable wholes, rather than by their component parts) and this holistic face processing is linked to brain activity in face-responsive brain regions. Although several brain regions outside of the face-responsive network are also sensitive to relational processing and perceptual grouping, whether these non-face-responsive regions contribute to holistic processing remains unclear. Here, we investigated holistic face processing in the composite face paradigm both within and outside of face-responsive brain regions. We recorded participants’ brain activity using fMRI while they performed a composite face task. Behavioural results indicate that participants tend to judge the same top face halves as different when they are aligned with different bottom face halves but not when they are misaligned, demonstrating a composite face effect. Neuroimaging results revealed significant differences in responses to aligned and misaligned faces in the lateral occipital complex (LOC), and trends in the anterior part of the fusiform face area (FFA2) and transverse occipital sulcus (TOS), suggesting that these regions are sensitive to holistic versus part-based face processing. Furthermore, the retrosplenial cortex (RSC) and the parahippocampal place area (PPA) showed a pattern of neural activity consistent with a holistic representation of face identity, which also correlated with the strength of the behavioural composite face effect. These results suggest that neural activity in brain regions both within and outside of the face-responsive network contributes to the composite-face effect.

The primary visual cortex of humans contains patches of neurons responding preferentially to stimulation of one eye (the ocular dominance columns). Multiple previous studies attempted to detect their activity using fMRI. The majority of these fMRI studies used magnetic field strengths of 4 ​T and higher. However, there have been reports of reliable eye-selective activations at 3 ​T as well. In this study we investigated the possibility of detecting eye-selective V1 activity using high-resolution GE-EPI fMRI at 3 ​T and sub-millimeter resolution fMRI at ultrahigh 9.4 ​T magnetic field strengths with acquisition parameters optimized for each field strength. High-resolution fMRI at 9.4 ​T also allowed us to examine the eye-selectivity responses across the cortical depth, which are expected to be strongest in the middle layers.We observed a substantial increase in the percentage of eye-selective voxels, as well as a doubling in run-to-run consistency of eye preference at ultrahigh field compared to 3 ​T. We also found that across cortical depth, eye selectivity increased towards the superficial layers, and that signal contrast increased while noise remained nearly constant towards the surface. The depth-resolved results are consistent with a distortion of spatial specificity of the GE-EPI signal by ascending venules and large draining veins on the cortical surface. The effects of larger vessels cause increasing signal amplitude, but also displacement of the maximum BOLD signal relative to neural activity.In summary, our results show that increase in spatial resolution, reduced partial volume effects, and improved sensitivity at 9.4 ​T allow for better detection of eye-selective signals related to ocular dominance columns. However, although ultrahigh field yields higher sensitivity to the ocular dominance signal, GE-EPI still suffers from specificity issues, with a prominent signal contribution at shallow depths from larger cortical vessels.

Summary: A key question in vision research concerns how the brain compensates for self-induced eye and head movements to form the world-centered, spatiotopic representations we perceive. Although human V3A and V6 integrate eye movements with vision, it is unclear which areas integrate head motion signals with visual retinotopic representations, as fMRI typically prevents head movement executions. Here we examined whether human early visual cortex V3A and V6 integrate these signals. A previously introduced paradigm allowed participant head movement during trials, but stabilized the head during data acquisition utilizing the delay between blood-oxygen-level-dependent (BOLD) and neural signals. Visual stimuli simulated either a stable environment or one with arbitrary head-coupled visual motion. Importantly, both conditions were matched in retinal and head motion. Contrasts revealed differential responses in human V6. Given the lack of vestibular responses in primate V6, these results suggest multi-modal integration of visual with neck efference copy signals or proprioception in V6. : Neuroscience; Sensory Neuroscience; Techniques in Neuroscience Subject Areas: Neuroscience, Sensory Neuroscience, Techniques in Neuroscience