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Highlights • Plinian eruptions linked to rheologically different mingling andesite magmas. • Magma decompression regimes producing variable degassing/crystallization kinetics. • Least explosive eruptions at slowest decompression, ascent and strain rates. • Plinian phases at rapid/intermittent magma decompression, ascent and strain rates. Abstract Estimating the kinetics of andesite magma vesiculation and crystallization inside volcanic plumbing systems is key for unraveling andesite Plinian eruption dynamics. The conduit kinetics provide the necessary input data for estimating the magma flow rates driving magma ascent and the fragmentation mechanisms controlling shifts in eruption explosivity and style. This information is crucial for increasing knowledge on expected hazards and for developing realistic eruption scenarios. In this work, we estimate conduit magma vesiculation and crystallization kinetics during the 3300 cal BP Upper Inglewood Plinian eruptive episode of Mount Taranaki, New Zealand. This episode comprised (i) low-intensity, conduit-opening phases of dome-collapse PDCs; (ii) pre-climactic, highly explosive phases of diverse PDCs, of up to violent 18-km-runout lateral blasts; (iii) climactic phases of steady 22-km-high Plinian eruption columns; and (iv) waning phases of column-collapse PDCs. By employing synchrotron microtomography, combined with mineral/glass chemistry and electron-microscopy, we quantified 3D vesicle and crystal size and shape distributions in juvenile pyroclasts over time, and corresponding number densities ranging from 1.1 × 105 to 2.5 × 106 mm−3 for vesicles, and from 8.0 × 104 to 5.1 × 106 mm−3 for crystals. Our results indicate that tapping of chemically alike yet rheologically contrasting magmas over a multi-phase andesite eruptive episode is linked to: (a) mafic magma recharge and differentiation in multiple storage reservoirs at distinct crustal levels, (b) stepwise to rapid magma decompression while mingling, producing variable pre- and syn-eruptive degassing and crystallization, and (c) syn-eruptive changes in melt viscosity, strain rate, localized shear deformation, and conduit geometry. The earliest and least explosive eruptive phases (≈ 2 × 106 kg s−1) were produced at the slowest rates of magma decompression (0.3–0.6 MPa s−1), ascent (0.01–0.02 m s−1) and strain (< 0.002 s−1), driven by volatile diffusion and exsolution. All subsequent pre-climactic and Plinian phases (4 × 107–1 × 108 kg s−1) were produced at either rapid or intermittent rates of magma decompression (2.0–6.0 MPa s−1), ascent (0.06–0.2 m s−1) and strain (> 0.003–0.010 s−1), powered by combined magma volatile supersaturation and delayed disequilibrium degassing, decompression-induced microlite crystallization and rapid heterogeneous vesiculation kinetics, shear deformation and magma mingling. These processes enabled complex fragmentation mechanisms of the rheologically most homogeneous magmas.

EBioMedicine 85, 104296 (2022). doi:10.1016/j.ebiom.2022.104296, Published by Elsevier, Amsterdam [u.a.]

To prevent oxygen contamination, additive manufacturing (AM) techniques normally operate in an inert gas chamber (GC). An alternative method, useful for large builds and components repair, is the application of localised shielding gas (LSG). The effect of oxygen contamination on Ti6242 during directed energy deposition (DED) AM using an inert GC compared to LSG was investigated by in situ synchrotron X-ray experiments. When processing in LSG mode, the amount of oxygen absorbed from the atmosphere was sufficient to reverse the Marangoni flow leading to an alteration of the molten pool geometry and strongly influencing defect formation. Microstructural analysis reveals that, at high oxygen levels, the commonly developed α' martensitic microstructure was completely suppressed, forming precipitation of a tetra modal microstructure of α phase consisting of globular, primary and secondary lamellae (in colonies) and basketweave structure. These results help elucidate the influence of oxygen contamination in additively manufactured Ti alloys, potentially enabling improved industrial practices for AM of titanium alloy.

Blended Elemental powders are an emerging alternative to pre-alloyed powders in metal additive manufacturing due to the wider range of alloys producible with them and the cost savings from not developing novel feedstock. In this study, in situ alloying and concurrent microstructure evolution during SLM are investigated by performing SLM on a BE Ti-185 powder while tracking the surface temperatures via Infra-red imaging and phase transforma- tion via synchrotron X-ray Diffraction. We then performed post-mortem electron microscopy (Backscatter Electron imaging, Energy Dispersive X-ray Spectroscopy and Electron Backscatter Diffraction) to further gain insight into microstructure development. We show that although exothermic mixing aids the melting process, laser melting results only in a mixture of alloyed and unmixed regions. Full alloying and thus a consistent microstructure is only achieved through further thermal cycling in the heat-affected zone.

Background and importance HydroSet is a hydroxyapatite cement that can be used for reconstruction of skull defects. We describe a case of HydroSet resorption resulting in intraventricular and leptomeningeal deposition or calcification, which is a previously unreported complication. Clinical presentation A patient who had a craniotomy augmented with HydroSet developed a pseudomeningocele, disappearance of cement fragments, and new hyperdense coating of the dura, upper cervical cord, and ventricles on CT after a fall. Conclusion r Resorption of a hydroxyapatite cement resulting in leptomeningeal and ependymal deposition or calcification have not been previously reported.

The Directed Energy Deposition Additive Manufacturing (DED-AM) of SS316L was studied using in situ and operando synchrotron X-ray imaging to quantitively understand the effect of processing parameters on the melt-pool morphology and surface quality. It was found that surface roughness of DED-AM builds can result from melt pool surface perturbations caused by changes in the melt flow and build stage motion perturbations. Process maps are developed that quantitatively correlate build quality to process parameters including powder feed rate, laser power and traverse speed. How the AM process parameters control build efficacy is clarified, and the processing conditions required to dampen surface perturbations leading to roughness were determined.

This paper provides insights into the effect of high thermal gradients and cooling rates on equiaxed grain nucleation and growth in conditions similar to those experienced during Additive Manufacturing (AM) processes. Bridgman type solidification is numerically simulated with columnar grains growing at a fixed pull rate under a user-imposed thermal gradient. Controlled inoculants of known nucleation undercooling were placed ahead of the growing columnar grains to allow quantitative analysis of nucleation events. At low thermal gradient and cooling rate only the inoculants with low nucleation undercooling were activated due to low melt undercooling driven by constitutional supercooling (CS). As the cooling rate is increased, for a given thermal gradient, a larger number of inoculants with higher nucleation undercoolings were activated. At higher cooling rates, thermal undercooling was generated by a lag in the growth rate of the solid-liquid (S-L) interface compared to the theoretical pull rate. Thus, thermal undercooling becomes dominant leading to the facilitation of nucleation on less potent substrates requiring higher undercooling. The results show a transition from solute-driven undercooling to cooling rate driven thermal undercooling which contributes to the undercooling that activates the nucleation events. Invoking the Interdependence model, it is also shown that the high cooling rate induced thermal undercooling reduces the size of the nucleation free zone substantially.

A 4D imaging study (3D + time) combining synchrotron tomography with in situ tensile testing has been carried out to observe the fibre and network level micromechanics of paper made from northern bleached softwood kraft (NBSK). Quantitative image analysis and digital volume correlation is used to characterize local deformation, the evolution of fibre-fibre contacts, and fibre straightening in a ”freeze-dried” handsheet as well as standard handsheets low consistency refined at different refining energies. In the freeze-dried handsheet having low fibre conformability, the results show that deformation at the network level occurs because of fibre straightening and possible inter-fibre bond breakage. Further, significant out-of-plane deformation near the failure regions was observed, which led to auxetic behaviour. In the refined handsheets, a strong inverse correlation is seen between refining energy, thickness expansion, and the number of broken fibres. The use of out-of-plane strain norms is proposed as a method to determine network efficiency (i.e. the ratio of the network’s elastic modulus to that of the constituent fibres) as well as the relative contribution of fibre pull-out to the overall failure of the handsheet.

Background: It is increasingly recognized that cancer progression induces systemic immune changes in the host. Alterations in number and function of immune cells have been identified in cancer patients’ peripheral blood and lymphoid organs. Recently, we found dysregulated cytokine signaling in peripheral blood T cells from breast cancer (BC) patients, even those with localized disease. Methods: We used phosphoflow cytometry to determine the clinical significance of cytokine signaling responsiveness in peripheral blood monocytes from non-metastatic BC patients at diagnosis. We also examined the correlation between cytokine signaling in peripheral monocytes and the number of tumor-infiltrating macrophages in paired breast tumors. Findings: Our results show that cytokine (IFNγ) signaling may also be dysregulated in peripheral blood monocytes at diagnosis, specifically in BC patients who later relapsed. Some patients exhibited concurrent cytokine signaling defects in monocytes and lymphocytes at diagnosis, which predict the risk of future relapse in two independent cohorts of BC patients. Moreover, IFNγ signaling negatively correlates with expression of CSF1R on monocytes, thus modulating their ability to infiltrate into tumors. Interpretation: Our results demonstrate that tumor-induced systemic immune changes are evident in peripheral blood immune cells for both myeloid and lymphoid lineages, and point to cytokine signaling responsiveness as important biomarkers to evaluate the overall immune status of BC patients. Funding: This study was supported by the Department of Defense Breast Cancer Research Program (BCRP), The V Foundation, Stand Up to Cancer (SU2C), and Breast Cancer Research Foundation (BCRF). Keywords: Breast cancer, Systemic immunity, Cytokine, Signal transduction, Peripheral monocytes, Peripheral lymphocytes, Clinical outcome

Considerations of gender/sex outcome and well-being among 46,XX individuals diagnosed with 21α-hydroxylase or 11β-hydroxylase deficiency congenital adrenal hyperplasia who were born with essentially male genitalia provide a complex model to consider gender/sex fluidity. Available outcome data focusing upon these 46,XX adults who were assigned male at birth and raised male are compared with those assigned and raised female. There is more extensive and detailed outcome data for those raised male than for those raised female, and these data suggest an overall good outcome in the male-assigned group regarding gender identity and social adjustment. While the majority of those raised female maintain a female gender identity (most recently reported at 88.7%), 23.8% report a nonheterosexual orientation; both percentages being greater than the general population. Within this model of genetic females with excessive fetal androgen exposure causing masculinization of external genitalia and impacting the central nervous system differentiation, there clearly is fluidity regarding gender development, related to both genetic (innate) and environmental factors.

Fe contamination is a serious composition barrier for Al recycling. In Fe-containing Al-Si-Cu alloy, a brittle and plate-shaped β phase forms, degrading the mechanical properties. Here, 4D (3D plus time) synchrotron X-ray tomography was used to observe the directional solidification of Fe-containing Al-Si-Cu alloy. The quantification of the coupled growth of the primary and β phase via machine learning and particle tracking, demonstrates that the final size of the β intermetallics were strongly influenced by the solute segregation and space available for growth whereas the β orientation was controlled by the temperature gradient direction. The work can be used to validate predictive models.

Summary Alternative battery technologies are required to meet growing energy demands and address the limitations of present technologies. As such, it is necessary to look beyond lithium-ion batteries. Zinc batteries enable high power density while being sourced from ubiquitous and cost-effective materials. This paper presents, for the first time known to the authors, multi-length scale tomography studies of failure mechanisms in zinc batteries with and without commercial microporous separators. In both cases, dendrites were grown, dissolved, and regrown, critically resulting in different morphology of dendritic layer formed on both the electrode and the separator. The growth of dendrites and their volume-specific areas were quantified using tomography and radiography data in unprecedented resolution. High-resolution ex situ analysis was employed to characterize single dendrites and dendritic deposits inside the separator. The findings provide unique insights into mechanisms of metal-battery failure effected by growing dendrites.

Adjuvant bisphosphonates improve disease outcomes in postmenopausal early breast cancer (EBC) but the long-term effects are poorly described. The AZURE trial (ISRCTN79831382) was designed to determine whether adjuvant zoledronic acid (ZOL) improves disease outcomes in EBC. Previous analyses showed no effect on overall outcomes but identified benefits in postmenopausal women. Here we present the long-term risks and benefits of adjuvant ZOL with 10-years follow-up. Patients and methods: 3360 patients with stage II/III breast cancer were included in an academic, international, phase III, randomized, open label trial. Patients were followed up on a regular schedule until 10 years. Patients were randomized on a 1:1 basis to standard adjuvant systemic therapy +/− intravenous ZOL 4 mg every 3–4 weeks x6, and then at reduced frequency to complete 5 years treatment. The primary outcome was disease free survival (DFS). Secondary outcomes included invasive DFS (IDFS), overall survival (OS), sites of recurrence, skeletal morbidity and treatment outcomes according to primary tumor amplification of the transcription factor, MAF. Pre-planned subgroup analyses focused on interactions between menopausal status and treatment effects. Results: With a median follow up of 117 months [IQR 70.4–120.4), DFS and IDFS were similar in both arms (HRDFS = 0.94, 95%CI = 0.84–1.06, p = 0.340; HRIDFS = 0.91, 95%CI = 0.82–1.02, p = 0.116). However, outcomes remain improved with ZOL in postmenopausal women (HRDFS = 0.82, 95%CI = 0.67–1.00; HRIDFS = 0.78, 95%CI = 0.64–0.94). In the 79% of tested women with a MAF FISH negative tumor, ZOL improved IDFS (HRIDFS = 0.75, 95%CI = 0.58–0.97) and OS HROS = 0.69, 95%CI = 0.50–0.94), irrespective of menopause. ZOL did not improve disease outcomes in MAF FISH + tumors. Bone metastases as a first DFS recurrence (BDFS) were reduced with ZOL (HRB-DFS = 0.76, 95%CI = 0.63–0.92, p = 0.005). ZOL reduced skeletal morbidity with fewer fractures and skeletal events after disease recurrence. 30 cases of osteonecrosis of the jaw in the ZOL arm (1.8%) have occurred. Conclusions: Disease benefits with adjuvant ZOL in postmenopausal early breast cancer persist at 10 years of follow-up. The biomarker MAF identified a patient subgroup that derived benefit from ZOL irrespective of menopausal status.

There is increasing demand for synthetic bone scaffolds for bone tissue engineering as they can counter issues such as potential harvesting morbidity and restrictions in donor sites which hamper autologous bone grafts and address the potential for disease transmission in the case of allografts. Due to their excellent biocompatibility, titanium scaffolds have great potential as bone graft substitutes as they mimic the structure and properties of human cancellous bone. Here we report on a new thermoset bio-polymer which can act as a binder for Direct Ink Writing (DIW) of titanium artificial bone scaffolds. We demonstrate the use of the binder to manufacture porous titanium scaffolds with evenly distributed and highly interconnected porosity ideal for orthopaedic applications. Due to their porous structure, the scaffolds exhibit an effective Young's modulus similar to human cortical bone, alleviating undesirable stress-shielding effects, and possess superior strength. The biocompatibility of the scaffolds was investigated in vitro by cell viability and proliferation assays using human bone-marrow-derived Mesenchymal stem cells (hMSCs). The hMSCs displayed well-spread morphologies, well-organized F-actin and large vinculin complexes confirming their excellent biocompatibility. The vinculin regions had significantly larger Focal Adhesion (FA) area and equivalent FA numbers compared to that of tissue culture plate controls, showing that the scaffolds support cell viability and promote attachment. In conclusion, we have demonstrated the excellent potential of the thermoset bio-polymer as a Direct Ink Writing ready binder for manufacture of porous titanium scaffolds for hard tissue engineering.

The authors regret that there were errors in Figs. 3 and 4, which in turn meant there were errors in Table 2. In Figs. 3 and 4, the lattice strain ((d-d0)/d0, where d is the lattice spacing) as a function of strain/stress should have plotted. Please find below the corrected versions of the figures and table. The authors would like to apologise for any inconvenience caused. Fig. 3. The evolution of elastic lattice strains along the axial and radial directions in grain families having {111}, {200}, {220}, {311} and {222} crystallographic planes during tensile loading at (a) 77 K and (b) 293 K.[Figure presented] Fig. 4. The (111) first order and (222) second order reflections together with the stacking fault probability as a function of true strain at (a) 77 K, (b) 293 K. [Figure presented] Table 2. Uniaxial materials properties of FeCoCrNi HEA at 77 and 293 K. [Table presented]

Understanding the microstructural stability of soft solids is key to optimizing formulations and processing parameters to improve the materials' properties. In this study, in situ synchrotron X-ray tomography is used to determine the temperature dependence of ice-cream's microstructural evolution, together with the underlying physical mechanisms that control microstructural stability. A new tomographic data processing method was developed, enabling the features to be segmented and quantified. The time-resolved results revealed that the melting-recrystallization mechanism is responsible for the evolution of ice crystal size and morphology during thermal cycling between −15 and −5 °C, while coalescence of air cells is the dominant coarsening mechanism controlling air bubble size and interconnectivity. This work also revealed other interesting phenomena, including the role of the unfrozen matrix in maintaining the ice cream's microstructural stability and the complex interactions between ice crystals and air structures, e.g. the melting and recrystallization of ice crystals significantly affect the air cell's morphology and the behavior of the unfrozen matrix. The results provide crucial information enhancing the understanding of microstructural evolution in multi-phase multi-state complex foodstuffs and other soft solids.

Scanning Electron Microscopy (SEM) based assessments are the most widely used and trusted imaging technique for mineral ore quantification. X-ray micro tomography (XMT) is a more recent to the mineralogy toolbox, but with the potential to extend the measurement capabilities into the three dimensional (3D) assessment of properties such as mineral liberation, grain size and textural characteristics. In addition, unlike SEM based assessments which require the samples to be sectioned, XMT is non-invasive and non-destructive manner. The disadvantage of XMT, though is that the mineralogy must be inferred from the X-Ray attenuation measurements, which can make it hard to distinguish from one another, whereas SEM when coupled with Energy-Dispersive X-raySpectroscopy (EDX) provides elemental compositions and thus a more direct method for distinguishing different minerals. A new methodology that combines both methods at the mineral grain level is presented. The rock particles used to test the method were initially imaged in 3D using XMT followed by sectioning and the 2D imaging of the slices using SEM-EDX. An algorithm was developed that allowed the mineral grains in the 2D slice to be matched with their 3D equivalents in the XMT based images. As the mineralogy of the grains from the SEM images can be matched to a range of X-Ray attenuations, this allows minerals which have similar attenuations to one another to be distinguished, with the level of uncertainty in the classification quantified. In addition,the methodology allowed for the estimation of the level of uncertainty in thequantification of grain size by XMT, the assessment of stereological effects in SEM 2D images and ultimately to obtain a simplified 3D mineral map from low energy XMT images. Copper sulphide ore fragments, with chalcopyrite and pyrite as the main sulphide minerals, were used to demonstrate the effectiveness of this procedure.

Bone mineralisation is a well-orchestrated procedure triggered by a protein-based template inducing the nucleation of hydroxyapatite (HA) nanocrystals on the matrix. In an attempt to fabricate superior nanocomposites from silk fibroin, textile braided structures made of natively spun fibres of Bombyx mori silkworm were compared against regenerated fibroin (lyophilized and films) underpinning the influence of intrinsic properties of fibroin matrices on HA nucleation. We found that native braids could bind Ca2 + ions through electrostatic attraction, which initiated the nucleation and deposition of HA, as evidenced by discrete shift in amide peaks via ATR-FTIR. This phenomenon also suggests the involvement of amide linkages in promoting HA nucleation on fibroin. Moreover, CaCl2-SBF immersion of native braids resulted in preferential growth of HA along the c-axis, forming needle-like nanocrystals and possessing Ca/P ratio comparable to commercial HA. Though regenerated lyophilized matrix also witnessed prominent peak shift in amide linkages, HA growth was restricted to (211) plane only, albeit at a significantly lower intensity than braids. Regenerated films, on the other hand, provided no crystallographic evidence of HA deposition within 7 days of SBF immersion. The present work sheds light on the primary fibroin structure of B. mori which probably plays a crucial role in regulating template-induced biomineralisation on the matrix. We also found that intrinsic material properties such as surface roughness, geometry, specific surface area, tortuosity and secondary conformation exert influence in modulating the extent of mineralisation. Thus our work generates useful insights and warrants future studies to further investigate the potential of bone mimetic, silk/mineral nanocomposite matrices for orthopaedic applications.

Existing outcomes for DSD individuals are inadequate because reports are based upon information collected retrospectively. This paper is presented to review existing data emphasizing information needed to lead to better future care, is based on presentations and discussions at a multi-disciplinary meeting on DSD held in Annecy in 2012, and is not intended to define the present status of management of each of the various DSD diagnoses. Rather it is intended to provide information needed to do studies regarding outcome data from the treatment of children with DSD by providing a summary of recommendations of 'patient-centered' topics that need investigation. The hope is that by being concerned with what is not known, new protocols will be developed for improving both early management and transition to adult life. (C) 2012 Published by Elsevier Ltd on behalf of Journal of Pediatric Urology Company.

Knowledge of the kinetics of gas bubble formation and evolution under cavitation conditions in molten alloys is important for the control casting defects such as porosity and dissolved hydrogen. Using in situ synchrotron X-ray radiography, we studied the dynamic behaviour of ultrasonic cavitation gas bubbles in a molten Al-10 wt% Cu alloy. The size distribution, average radius and growth rate of cavitation gas bubbles were quantified under an acoustic intensity of 800 W/cm2 and a maximum acoustic pressure of 4.5 MPa (45 atm). Bubbles exhibited a log-normal size distribution with an average radius of 15.3 ± 0.5 μm. Under applied sonication conditions the growth rate of bubble radius, R(t), followed a power law with a form of R(t) = αtβ, and α = 0.0021 & β = 0.89. The observed tendencies were discussed in relation to bubble growth mechanisms of Al alloy melts. The work was made possible by the financial support from the ExoMet Project (which is co-funded by the European Commission in the 7th Framework Programme (contract FP7-NMP3-LA-2012-280421), by the European Space Agency and by the individual partner organisations), from the UK EPSRC grants (EP/I02249X/1, EP/K00588X/1, EP/K005804/1) and the Research Complex at Harwell.

Superconducting wires and cables are employed in many application fields, from NMR and MRI magnets, to high field magnets for test equipments, for nuclear fusion devices or for accelerators, where the low temperature superconductors Nb–Ti and Nb 3 Sn are typically used. The possibility to use liquid nitrogen or cryo-free cooling technologies for high temperature superconductors, such as Bi-2223 or REBCO tapes, is driving important developments in applications such as power transmission lines. Promising for very high field applications at low temperature are the properties of Bi-2212 round wires, still to reach a well assessed industrialization, and of REBCO tapes, that would require further cost reduction. MgB2 offers the potential of a low-cost superconductor that could be operated at reduced refrigeration costs due to its high T c . Interesting J c values have also been achieved in the novel Fe-based materials. The main requirements for superconducting wires and cables are summarized in the paper; the type of processing and the current development status is reported for each material.

The endoplasmic reticulum membrane proteins Insig-1 and Insig-2 limit cholesterol synthesis, in part through their sterol-dependent binding to sterol-regulatory element binding protein (SREBP) cleavage-activating protein (SCAP). This binding prevents proteolytic processing of SREBPs, membrane-bound transcription factors that enhance cholesterol synthesis. We report here the characterization of mutant Chinese hamster ovary (CHO) cells, designated SRD-19, that are resistant to 25-hydroxycholesterol, a potent inhibitor of SREBP processing. SRD-19 cells were produced by mutagenesis of Insig-1-deficient SRD-14 cells, followed by selection in high levels of 25-hydroxycholesterol. 25-Hydroxycholesterol fails to suppress SREBP processing in SRD-19, even though they express normal levels of Insig-2. The number of copies of the gene encoding SCAP was found to be increased by 4-fold in SRD-19 cells compared with wild-type CHO cells, leading to the overproduction of SCAP mRNA and protein. Our data indicate that overproduced SCAP saturates the remaining Insig-2 in SRD-19 cells, thus explaining their resistance to 25-hydroxycholesterol. Consistent with this conclusion, regulated SREBP processing is restored in SRD-19 cells upon transfection of plasmids encoding either Insig-1 or Insig-2. These results highlight the importance of SCAP/Insig ratios in normal sterol-regulated processing of SREBPs in cultured cells.

Interfacial free energies strongly influence many materials properties, especially for nanomaterials that have very large interfacial areas per unit volume. Quantitative evaluation of interfacial free energy by means of computer simulation remains difficult in these cases, especially at finite temperature. Density Functional Theory (DFT) simulation offers a robust way to compute both the energies and structures of the relevant surfaces and interfaces at the atomic level at zero Kelvin, and can be extended to finite temperatures in solids by means of the harmonic approximation (HA). Here we study the Mg/MgO interface, employing DFT calculations within the HA to obtain its key physical properties. We calculate the free energies of several key surfaces/interfaces when the temperature (T) increases from 0 K to 800 K, finding that all free energies decrease almost linearly with T. We have considered two surfaces, Mg(0001) (0.520–0.486 J/m 2 ), and MgO(100) (0.86–0.52 J/m 2 ), and two Mg(0001)//MgO(100) interfaces with the Mg–Mg and Mg–O stacking sequences at the interface planes (1.048–0.873 J/m 2 and 0.910 to 0.743 J/m 2 respectively). Using these values we determine the interfacial free energy as a function of temperature and size for MgO nanoparticles in solid Mg, an important metal matrix nanocomposite material.

A first attempt at the three-dimensional evaluation of naturally initiated surface connected and internal fatigue cracks is presented. Fatigue crack initiation and growth in air and vacuum environments have been investigated through X-ray microtomography in air and vacuum environments at elevated temperatures (350 °C), accompanied by post-mortem electron microscopy of the fracture surfaces. In vacuum ( 10 −5 mbar), multiple internal and surface-connected crack initiation was observed, but only the surface-connected cracks grew. In contrast, fewer cracks formed in air, these were mostly surface-connected and all were observed to grow. In all instances the initiation features were associated with globular primary α . An improved fatigue life was found in vacuum, which was mostly a consequence of delayed initiation, but was also due to slower fatigue crack propagation. The non-propagation of internal cracks was taken to imply that even the good laboratory vacuum obtained here was insufficient to simulate the conditions obtained for an internal crack in a component. The crack shape evolved towards a semi-circular shape a / c = 1 in air during fatigue crack growth, whilst the vacuum cracks remained semi-elliptical ( a / c ≃ 1.4 ). This was taken to imply that oxide-induced crack closure played a role in fatigue crack growth in air.

An in situ synchrotron radiographic study of a molten Al-10 wt% Cu alloy under the influence of an external ultrasonic field was carried out using the Diamond-Manchester Branchline pink X-ray imaging at the Diamond Light Source in UK. A bespoke test rig was used, consisting of an acoustic transducer with a titanium sonotrode coupled with a PID-controlled resistance furnace. An ultrasonic frequency of 30 kHz, with a peak to peak amplitude at 140 microns, was used, producing a pressure output of 16.9 MPa at the radiation surface of the 1-mm diameter sonotrode. This allowed quantification of not only the cavitation bubble formation and collapse, but there was also evidence of the previously hypothesised ultrasonic capillary effect (UCE), providing the first direct observations of this phenomenon in a molten metallic alloy. This was achieved by quantifying the re-filling of a pre-existing groove in the shape of a tube (which acted as a micro-capillary channel) formed by the oxide envelope of the liquid sample. Analytical solutions of the flow suggest that the filling process, which took place in very small timescales, was related to micro-jetting from the collapsing cavitation bubbles. In addition, a secondary mechanism of liquid penetration through the groove, which is related with the density distribution of the oxides inside the groove, and practically to the filtration of aluminium melt from oxides, was revealed. The observation of the almost instantaneous re-filling of a micro-capillary channel with the metallic melt supports the hypothesised sono-capillary effect in technologically important liquids other than water, like metallic alloys with substantially higher surface tension and density. ExoMet Project which is co-funded by the European Commission in the 7th Framework Programme (contract FP7-NMP3-LA-2012-280421), by the European Space Agency and by the individual partner organisations, the UK Engineering and Physical Sciences Research Council (EPSRC) (EP/K005804/1 and EP/I02249X/1) and the Research Complex at Harwell.

The paper presents the first application of laboratory X-ray μCT for post-mortem analysis of a failed lithium-ion polymer battery pouch cell. Analysis of the μCT data allowed quantification of the physical distortion within the individual cell layers of both an untested and failed cell. In the failed cell, the maximum separation of the electrode assemblies was measured in each direction (XY=833 μm, YZ=787 μm), representing a significant increase from the untested cell, where the spacing was below 43 μm. Deformation was more prominent in the central region of the cell since both ends of the battery electrodes remained tightly clamped even after failure. Based on the visually observed volume expansion and the deformation of the cell architecture observed by μCT we conclude that the deformation was caused by pressure build up as a result of gas generation, which could have arisen from a short circuit in the cell. Keywords: Li-ion Battery, Failure analysis, X-ray μCT

Numerous aspects of the immune system operate on the basis of complex regulatory networks that are amenable to mathematical and computational modeling. Several modeling frameworks have recently been applied to simulating the immune system, including systems of ordinary differential equations, delay differential equations, partial differential equations, agent-based models, and stochastic differential equations. In this chapter, we summarize several recent examples of work that has been done in immune modeling and discuss two specific examples of models based on DDEs that can be used to understand the dynamics of T cell regulation.

International audience; During the twin roll casting of Al alloys, the interdendritic liquid may flow as the two solidification fronts are compressed together between the rolls. This can lead to defects such as centerline segregation. To understand the flow properties of the interdendritic liquid, samples of Al–12 wt.% Cu were solidified directionally in a Bridgman furnace and quenched to capture the growing columnar dendritic structures. The quenched samples were scanned using a laboratory X-ray microtomography (XMT) unit to obtain the 3D structure with a voxel resolution of 7.2 μm. Image analysis was used to separate the Al dendrite from the interdendritic Al–Al2Cu eutectic. Flow between the dendrites was simulated by solving the Stokes equation to calculate the permeability tensor as a function of the fraction solid. The results were compared to prior experimental measurements and calculations using synchrotron tomography observations of equiaxed structures. Elasto–plastic finite element (FE) simulations were performed on the dendritic structures to determine flow stress behavior as a function of fraction solid. It was found that the standard approximations for the reduction in flow stress in the semi-solid have a variation in excess of 100% from that calculated using the true structure. Therefore, it is critical to simulate the actual dendrite for effective flow stress determination.

This chapter focuses on some of the biological and practical issues related to the use of peptide/major histocompatibility complex (pMHC) tetramers. The basic components of a pMHC complex (class I) include the peptide, MHC class I molecule, and beta-2-microglobulin. For subsequent tetramerization, the MHC class I molecule is engineered with a C-terminal substrate peptide for BirA-mediated biotinylation, biotin signal peptide (bsp). This MHC l-bsp recombinant protein is generally produced using E. coli in inclusion bodies. There are now numerous human and mouse MHC I alleles engineered with bsp in efficient E. coli expression vectors. The first step when a new tetramer is made is to validate and titrate the reagent. Tetramers may fail for a number of reasons—peptides of very low MHC binding affinity do not fold into pMHC complexes well, incomplete purification or biotinylation of pMHC complexes, or bad batches of streptavidin–fluorophore . A T cell line or clone specific for the pMHC complex in the tetramer is needed for this process. The chapter discusses some of the advanced uses of pMHC tetramers. The use of MHC class I tetramers in humans is briefly described.