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Micro X-ray diffraction imaging of the spatial distribution of charge-density-wave puddles and quenched disorder in HgBa 2 CuO 4 + y reveals a complex, inhomogeneous spatial landscape due to the interplay between charge and dopant order. The geometry of high- T c superconductors The geometry favouring the high-transition-temperature superconducting state ( T c ) emerges from the coexistence of charge-density-wave order and quenched disorder. Gaetano Campi et al . have used micro X-ray diffraction imaging to study the spatial distribution of charge-density-wave 'puddles' and quenched disorder in HgBa 2 CuO 4+ y . They describe a complex, inhomogeneous spatial landscape resulting from the interplay between charge and dopant order. The charge-density-wave puddles, like the steam bubbles in boiling water, show a size distribution typical of self-organization near a critical point. The quenched disorder shows a distribution contrary to the usual assumed random uncorrelated distribution. It has recently been established that the high-transition-temperature (high- T c ) superconducting state coexists with short-range charge-density-wave order 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 and quenched disorder 12 , 13 arising from dopants and strain 14 , 15 , 16 , 17 . This complex, multiscale phase separation 18 , 19 , 20 , 21 invites the development of theories of high-temperature superconductivity that include complexity 22 , 23 , 24 , 25 . The nature of the spatial interplay between charge and dopant order that provides a basis for nanoscale phase separation remains a key open question, because experiments have yet to probe the unknown spatial distribution at both the nanoscale and mesoscale (between atomic and macroscopic scale). Here we report micro X-ray diffraction imaging of the spatial distribution of both short-range charge-density-wave ‘puddles’ (domains with only a few wavelengths) and quenched disorder in HgBa 2 CuO 4 + y , the single-layer cuprate with the highest T c , 95 kelvin (refs 26 , 27 , 28 ). We found that the charge-density-wave puddles, like the steam bubbles in boiling water, have a fat-tailed size distribution that is typical of self-organization near a critical point 19 . However, the quenched disorder, which arises from oxygen interstitials, has a distribution that is contrary to the usually assumed random, uncorrelated distribution 12 , 13 . The interstitial-oxygen-rich domains are spatially anticorrelated with the charge-density-wave domains, because higher doping does not favour the stripy charge-density-wave puddles, leading to a complex emergent geometry of the spatial landscape for superconductivity.

Elettra is one of the first 3rd-generation storage rings, recently upgraded to routinely operate in top-up mode at both 2.0 and 2.4 GeV. The facility hosts four dedicated beamlines for crystallography, two open to the users and two under construction, and expected to be ready for public use in 2015. In service since 1994, XRD1 is a general-purpose diffraction beamline. The light source for this wide (4–21 keV) energy range beamline is a permanent magnet wiggler. XRD1 covers experiments ranging from grazing incidence X-ray diffraction to macromolecular crystallography, from industrial applications of powder diffraction to X-ray phasing with long wavelengths. The bending magnet powder diffraction beamline MCX has been open to users since 2009, with a focus on microstructural investigations and studies under non-ambient conditions. A superconducting wiggler delivers a high photon flux to a new fully automated beamline dedicated to macromolecular crystallography and to a branch beamline hosting a high-pressure powder X-ray diffraction station (both currently under construction). Users of the latter experimental station will have access to a specialized sample preparation laboratory, shared with the SISSI infrared beamline. A high throughput crystallization platform equipped with an imaging system for the remote viewing, evaluation and scoring of the macromolecular crystallization experiments has also been established and is open to the user community.

The degenerative effects of multiple sclerosis at the level of the vascular and neuronal networks in the central nervous system are currently the object of intensive investigation. Preclinical studies have demonstrated the efficacy of mesenchymal stem cell (MSC) therapy in experimental autoimmune encephalomyelitis (EAE), the animal model for multiple sclerosis, but the neuropathology of specific lesions in EAE and the effects of MSC treatment are under debate. Because conventional imaging techniques entail protocols that alter the tissues, limiting the reliability of the results, we have used non-invasive X-ray phase-contrast tomography to obtain an unprecedented direct 3D characterization of EAE lesions at micro-to-nano scales, with simultaneous imaging of the vascular and neuronal networks. We reveal EAE-mediated alterations down to the capillary network. Our findings shed light on how the disease and MSC treatment affect the tissues, and promote X-ray phase-contrast tomography as a powerful tool for studying neurovascular diseases and monitoring advanced therapies.

The paper shows how a table top superbright microfocus laboratory X-ray source and an innovative restoring-data algorithm, used in combination, allow to analyze the super molecular structure of soft matter by means of Small Angle X-ray Scattering ex-situ experiments. The proposed theoretical approach is aimed to restore diffraction features from SAXS profiles collected from low scattering biomaterials or soft tissues and therefore to deal with extremely noisy diffraction SAXS profiles/maps. As biological test cases we inspected: i ) residues of exosomes' drops from healthy epithelial colon cell line and colorectal cancer cells; ii ) collagen/human elastin artificial scaffolds developed for vascular tissue engineering applications; iii ) apoferritin protein in solution. Our results show how this combination can provide morphological/structural nanoscale information to characterize new artificial biomaterials and/or to get insight into the transition between healthy and pathological tissues during the progression of a disease, or to morphologically characterize nanoscale proteins, based on SAXS data collected in a room-sized laboratory.

The investigation of the neuronal network in mouse spinal cord models represents the basis for the research on neurodegenerative diseases. In this framework, the quantitative analysis of the single elements in different districts is a crucial task. However, conventional 3D imaging techniques do not have enough spatial resolution and contrast to allow for a quantitative investigation of the neuronal network. Exploiting the high coherence and the high flux of synchrotron sources, X-ray Phase-Contrast multiscale-Tomography allows for the 3D investigation of the neuronal microanatomy without any aggressive sample preparation or sectioning. We investigated healthy-mouse neuronal architecture by imaging the 3D distribution of the neuronal-network with a spatial resolution of 640 nm. The high quality of the obtained images enables a quantitative study of the neuronal structure on a subject-by-subject basis. We developed and applied a spatial statistical analysis on the motor neurons to obtain quantitative information on their 3D arrangement in the healthy-mice spinal cord. Then, we compared the obtained results with a mouse model of multiple sclerosis. Our approach paves the way to the creation of a “database” for the characterization of the neuronal network main features for a comparative investigation of neurodegenerative diseases and therapies.

It has recently been established that the high-transition-temperature (high-[T.sub.c]) superconducting state coexists with short-range charge-density-wave order (1-11) and quenched disorder (12, 13) arising from dopants and strain (14-17). This complex, multiscale phase separation (18-21) invites the development of theories of high-temperature superconductivity that include complexity (22-25). The nature of the spatial interplay between charge and dopant order that provides a basis for nanoscale phase separation remains a key open question, because experiments have yet to probe the unknown spatial distribution at both the nanoscale and mesoscale (between atomic and macroscopic scale). Here we report micro X-ray diffraction imaging of the spatial distribution of both short-range charge-density-wave 'puddles' (domains with only a few wavelengths) and quenched disorder in Hg[Ba.sub.2]Cu[O.sub.4] + y the single-layer cuprate with the highest [T.sub.c], 95 kelvin (refs 26-28). We found that the charge-density-wave puddles, like the steam bubbles in boiling water, have a fat-tailed size distribution that is typical of self-organization near a critical point (19). However, the quenched disorder, which arises from oxygen interstitials, has a distribution that is contrary to the usually assumed random, uncorrelated distribution (12, 13). The interstitial-oxygen-rich domains are spatially anticorrelated with the charge-density-wave domains, because higher doping does not favour the stripy charge-density-wave puddles, leading to a complex emergent geometry of the spatial landscape for superconductivity.

This study investigates the uptake of iron and aluminium by apoferritin. In particular, we provide the first evidence that apoferritin is able to bind in vitro the physiological form of aluminium, Al(OH) 4 − , to reach an Al/Fe atomic ratio of about 0.15. Mass spectrometry analysis shows that the Al content increases linearly as a function of Al concentration in solution. These findings provide a better understanding of the Al uptake in vivo, confirming that the metal content of ferritin depends on the metal bio-availability.

The immunological synapse is a specialized cell-cell junction that is defined by large-scale spatial patterns of receptors and signaling molecules yet remains largely enigmatic in terms of formation and function. We used supported bilayer membranes and nanometer-scale structures fabricated onto the underlying substrate to impose geometric constraints on immunological synapse formation. Analysis of the resulting alternatively patterned synapses revealed a causal relation between the radial position of T cell receptors (TCRs) and signaling activity, with prolonged signaling from TCR microclusters that had been mechanically trapped in the peripheral regions of the synapse. These results are consistent with a model of the synapse in which spatial translocation of TCRs represents a direct mechanism of signal regulation.