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This compact, Creative-Commons-licensed ultra-SAXS module, augments existing high-performance SAXS/WAXS synchrotron instruments, so that larger structures may be measured. Its functionality is demonstrated at the I22 beamline at Diamond Light Source, where the combined USAXS/SAXS/WAXS range of an alumina membrane, a porous carbon catalyst and silica, covers over four decades in scattering angle., Ultra-SAXS can enhance the capabilities of existing synchrotron SAXS/WAXS beamlines. A compact ultra-SAXS module has been developed, which extends the measurable q-range with 0.0015 ≤ q (nm−1) ≤ 0.2, allowing structural dimensions in the range 30 ≤ D (nm) ≤ 4000 to be probed in addition to the range covered by a high-end SAXS/WAXS instrument. By shifting the module components in and out on their respective motor stages, SAXS/WAXS measurements can be easily and rapidly interleaved with USAXS measurements. The use of vertical crystal rotation axes (horizontal diffraction) greatly simplifies the construction, at minimal cost to efficiency. In this paper, the design considerations, realization and synchrotron findings are presented. Measurements of silica spheres, an alumina membrane, and a porous carbon catalyst are provided as application examples.

Multicomponent hydrogels offer a tremendous opportunity for preparing useful and exciting materials that cannot be accessed using a single component. Here, we describe an unusual multi‐component low‐molecular weight gelling system that exhibits pH‐responsive behavior involving cooperative hydrogen bonding between the components, allowing it to maintain a gel phase across a wide pH range. Unlike traditional acid‐triggered gels, our system undergoes a change in the underlying molecular packing and maintains the β‐sheet structure both at acidic and basic pH. We further establish that autonomous programming between these two gel states is possible by an enzymatic reaction which allows us to prepare gels with improved mechanical properties., We show that a multicomponent supramolecular gel with two opposite ionizable pendant groups on different components can exhibit unusual phase behavior involving cooperative hydrogen bonding between the components, allowing it to maintain a gel phase across a wide pH range. Autonomous programming between these two gel states is possible by an enzymatic reaction which allows the preparation of gels with improved mechanical properties.

A detailed understanding of the local dynamics in ionic liquids remains an important aspect in the design of new ionic liquids as advanced functional fluids. Here, we use small-angle X-ray scattering and quasi-elastic neutron spectroscopy to investigate the local structure and dynamics in a model ionic liquid as a function of temperature and pressure, with a particular focus on state points (P,T) where the macroscopic dynamics, i.e., conductivity, is the same. Our results suggest that the initial step of ion transport is a confined diffusion process, on the nanosecond timescale, where the motion is restricted by a cage of nearest neighbors. This process is invariant considering timescale, geometry, and the participation ratio, at state points of constant conductivity, i.e., state points of isoconductivity. The connection to the nearest-neighbor structure is underlined by the invariance of the peak in the structure factor corresponding to nearest-neighbor correlations. At shorter timescales, picoseconds, two localized relaxation processes of the cation can be observed, which are not directly linked to ion transport. However, these processes also show invariance at isoconductivity. This points to that the overall energy landscape in ionic liquids responds in the same way to density changes and is mainly governed by the nearest-neighbor interactions.

The mechanical properties of connective tissues are tailored to their specific function, and changes can lead to dysfunction and pathology. In most mammalian tissues the mechanical environment is governed by the micro- and nano-scale structure of collagen and its interaction with other tissue components, however these hierarchical properties remain poorly understood. In this study we use the human cornea as a model system to characterise and quantify the dominant deformation mechanisms of connective tissue in response to cyclic loads of physiological magnitude. Synchronised biomechanical testing, x-ray scattering and 3D digital image correlation revealed the presence of two dominant mechanisms: collagen fibril elongation due to a largely elastic, spring-like straightening of tropocollagen supramolecular twist, and a more viscous straightening of fibril crimp that gradually increased over successive loading cycles. The distinct mechanical properties of the two mechanisms suggest they have separate roles in vivo. The elastic, spring-like mechanism is fast-acting and likely responds to stresses associated with the cardiac cycle, while the more viscous crimp mechanism will respond to slower processes, such as postural stresses. It is anticipated that these findings will have broad applicability to understanding the normal and pathological functioning of other connective tissues such as skin and blood vessels that exhibit both helical structures and crimp. Statement of significance: The tropocollagen spring mechanism allows collagen fibrils from some tissues to elongate significantly under small loads, and its recent discovery has the potential to change our fundamental understanding of how tissue deforms. This time-resolved study quantifies the contribution of the spring mechanism to the local strain in stretched tissue and compares it to the contribution associated with the straightening of fibril waviness, the widely accepted primary low-load strain mechanism. The spring mechanism contributed more to the local tissue strain than fibril straightening, and was found to be elastic while fibril straightening was more viscous. The results suggest that the viscoelastic behaviour of a biomaterial is controlled, at least in part, by the relative amount of fibril-scale crimp and tropocollagen supramolecular twist.

This study shows how a few nanometer-sized crystals markedly increase the viscosity of a magma leading to explosive eruptions., Although gas exsolution is a major driving force behind explosive volcanic eruptions, viscosity is critical in controlling the escape of bubbles and switching between explosive and effusive behavior. Temperature and composition control melt viscosity, but crystallization above a critical volume (>30 volume %) can lock up the magma, triggering an explosion. Here, we present an alternative to this well-established paradigm by showing how an unexpectedly small volume of nano-sized crystals can cause a disproportionate increase in magma viscosity. Our in situ observations on a basaltic melt, rheological measurements in an analog system, and modeling demonstrate how just a few volume % of nanolites results in a marked increase in viscosity above the critical value needed for explosive fragmentation, even for a low-viscosity melt. Images of nanolites from low-viscosity explosive eruptions and an experimentally produced basaltic pumice show syn-eruptive growth, possibly nucleating a high bubble number density.

Aluminium alloys can be strengthened significantly by nano-scale precipitates that restrict dislocation movement. In this study, the evolution of inhomogenously distributed trialuminide precipitates in two multi-component alloys was characterised by synchrotron small-angle X-ray scattering (SAXS). The appropriate selection of reference sample and data treatment required to successfully characterise a low volume fraction of precipitates in multi-component alloys via SAXS was investigated. The resulting SAXS study allowed the analysis of statistically significant numbers of precipitates (billions) as compared to electron microscopy (hundreds). Two cast aluminium alloys with different volume fractions of Al3ZrxV1-x precipitates were studied. Data analysis was conducted using direct evaluation methods on SAXS spectra and the results compared with those from transmission electron microscopy (TEM). Precipitates were found to attain a spherical structure with homogeneous chemical composition. Precipitate evolution was quantified, including size, size distribution, volume fraction and number density. The results provide evidence that these multi-component alloys have a short nucleation stage, with coarsening dominating precipitate size. The coarsening rate constant was calculated and compared to similar precipitate behaviour.

Understanding structure-property relationships is critical for the development of new drug delivery systems. This study investigates the properties of Pluronic smart hydrogel formulations for future use as injectable controlled drug carriers. The smart hydrogels promise to enhance patient compliance, decrease side effects and reduce dose and frequency. Pharmaceutically, these systems are attractive due to their unique sol-gel phase transition in the body, biocompatibility, safety and injectability as solutions before transforming into gel matrices at body temperature. We quantify the structural changes of F127 systems under controlled temperature after flow, as experienced during real bodily injection. Empirical formulae combining the coupled thermal and shear dependency are produced to aid future application of these systems. Induced structural transitions measured in-situ by small angle x-ray and neutron scattering reveal mixed oriented structures that can be exploited to tailor the drug release profile.

Residual Stresses 2018, ECRS10, Leuven, Belgium, 11 Sep 2018 - 14 Sep 2018; Materials research proceedings 6, 117 - 122 (2018). doi:10.21741/9781945291890-19, The major challenge of Research in bone surgery is to develop strategies to repair large bone defects. Bone grafting technique is the gold standard to fill and heal these kind of defects. This work address the evolution of the mechanical properties as regard to bone regeneration microstructure. Managing such a time dependent (different regeneration step) and spatially resolved (strain field across natural/reconstructed bone interface) process is achieved through a quantitative analysis of the mechanical strain distribution supported by the mineral part of bone architecture (hydroxyapatite – Hap) and crystal microstructural features (size distribution, spatial pattern). SAXS/WAXS (Small- and Wide- Angle X-ray Scattering) experiments will highlight strain distribution respectively in the reconstructed bone’s collagen fibrils and minerals, through mechanical state mapping over a surgically created defect under in situ tensile testing on samples harvested at different regeneration stages., Published by Materials Research Forum LLC, Millersville, PA

This study focuses on how the mesophase transition behaviour of the phospholipid dioleoyl phosphatidylethanolamine (DOPE) is altered by the presence of 10 nm hydrophobic and 14 nm hydrophilic silica nanoparticles (NPs) at different concentrations. The lamellar to inverted hexagonal phase transition (Lα-HII) of phospholipids is energetically analogous to the membrane fusion process, therefore understanding the Lα-HII transition with nanoparticulate additives is relevant to how membrane fusion may be affected by these additives, in this case the silica NPs. The overriding observation is that the HII/Lα boundaries in the DOPE p-T phase diagram were shifted by the presence of NPs: the hydrophobic NPs enlarged the HII phase region and thus encouraged the inverted hexagonal (HII) phase to occur at lower temperatures, whilst hydrophilic NPs appeared to stabilise the Lα phase region. This effect was also NP-concentration dependent, with a more pronounced effect for higher concentration of the hydrophobic NPs, but the trend was less clear cut for the hydrophilic NPs. There was no evidence that the NPs were intercalated into the mesophases, and as such it was likely that they might have undergone microphase separation and resided at the mesophase domain boundaries. Whilst the loci and exact roles of the NPs invite further investigation, we tentatively discuss these results in terms of both the surface chemistry of the NPs and the effect of their curvature on the elastic bending energy considerations during the mesophase transition.

The electrophoresis of a well-established model system of charged colloids in nonpolar solvents has been studied as a function of particle volume fraction at constant surfactant concentration. Dispersions of poly(12-hydroxystearic acid)-stabilized poly(methyl methacrylate) (PMMA) latexes in dodecane were prepared with added Aerosol OT surfactant as the charging agent. The electrophoretic mobility (μ) of the PMMA latexes is found to decrease with particle concentration. The particles are charged by a small molecule charging agent (AOT) at finite concentration, and this makes the origin of this decrease in μ unclear. There are two suggested explanations. The decrease could either be due to the reservoir of available surfactant being exhausted at high particle concentrations or the interactions between the charged particles at high particle number concentrations. Contrast-variation small-angle neutron scattering measurements of PMMA latexes and deuterated AOT-d34 surfactant in latex core contrast-matched solvent were used to study the former, and electrokinetic modeling was used to study the latter. As the same amount of AOT-d34 is found to be incorporated with the latexes at all volume fractions, the solvodynamic and electrical interactions between particles are determined to be the explanation for the decrease in mobility. These measurements show that, for small latexes, there are interactions between the charged particles at all accessible particle volume fractions and that it is necessary to account for this to accurately determine the electrokinetic ζ potential.

The primary aim of this study was to quantify the relationship between corneal structure and hydration in humans and pigs. X-ray scattering data were collected from human and porcine corneas equilibrated with polyethylene glycol (PEG) to varying levels of hydration, to obtain measurements of collagen fibril diameter, interfibrillar spacing (IFS) and intermolecular spacing. Both species showed a strong positive linear correlation between hydration and IFS2 and a nonlinear, bi-phasic relationship between hydration and fibril diameter, whereby fibril diameter increased up to approximately physiological hydration, H = 3.0, with little change thereafter. Above H = 3.0, porcine corneas exhibited a larger fibril diameter than human corneas (p < 0.001). Intermolecular spacing also varied with hydration in a bi-phasic manner but reached a maximum value at a lower hydration (H = 1.5) than fibril diameter. Human corneas displayed a higher intermolecular spacing than porcine corneas at all hydrations (p < 0.0001). Human and porcine corneas required a similar PEG concentration to reach physiological hydration, suggesting that the total fixed charge that gives rise to the swelling pressure is the same. The difference in their structural responses to hydration can be explained by variations in molecular cross-linking and intra/interfibrillar water partitioning.

Details of a preliminary study performed to determine the minimum time required for equilibration to occur

Frustration of crystallisation by locally favoured structures is critically important in linking the phenomena of supercooling, glass formation, and liquid-liquid transitions. Here we show that the putative liquid-liquid transition in n-butanol is in fact caused by geometric frustration associated with an isotropic to rippled lamellar liquid-crystal transition. Liquid-crystal phases are generally regarded as being “in between” the liquid and the crystalline state. In contrast, the liquid-crystal phase in supercooled n-butanol is found to inhibit transformation to the crystal. The observed frustrated phase is a template for similar ordering in other liquids and likely to play an important role in supercooling and liquid-liquid transitions in many other molecular liquids.

HypothesisPoly(methyl methacrylate) (PMMA) latexes in nonpolar solvents are an excellent model system to understand phenomena in low dielectric media, and understanding their internal structure is critical to characterizing their performance in both fundamental studies of colloidal interactions and in potential industrial applications. Both the PMMA cores and the poly(12-hydroxystearic acid) (PHSA) shells of the latexes are known to be penetrable by solvent and small molecules, but the relevance of this for the properties of these particles is unknown.ExperimentsThese particles can be prepared in a broad range of sizes, and two PMMA latexes dispersed in n-dodecane (76 and 685 nm in diameter) were studied using techniques appropriate to their size. Small-angle scattering (using both neutrons and X-rays) was used to study the small latexes, and analytical centrifugation was used to study the large latexes. These studies enabled the calculation of the core densities and the amount of solvent in the stabilizer shells for both latexes. Both have consequences on interpreting measurements using these latexes.FindingsThe PHSA shells are highly solvated (∼85% solvent by volume), as expected for effective steric stabilizers. However, the PHSA chains do contribute to the intensity of neutron scattering measurements on concentrated dispersions and cannot be ignored. The PMMA cores have a slightly lower density than PMMA homopolymer, which shows that only a small free volume is required to allow small molecules to penetrate into the cores. Interestingly, the observations are essentially the same, regardless of the size of the particle; these are general features of these polymer latexes. Despite the latexes being used as a model physical system, the internal chemical structure is complex and must be fully considered when characterizing them.

We use a combination of diamond anvil cell techniques and large volume (multi-anvil press, piston cylinder) devices to study the synthesis, structure and properties of new materials under high pressure conditions. The work often involves the study of structural and phase transformations occurring in the metastable regime, as we explore the phase space determined as a function of the pressure, temperature and chemical composition. The experimental studies are combined with first principles calculations and molecular dynamics simulations, as we determine the structures and properties of new phases and the nature of the transformations between them. Problems currently under investigation include structural studies of transition metal and main group nitrides, oxides and oxynitrides at high pressure, exploration of new solid-state compounds that are formed within the C-N-O system, polyamorphic low- to high-density transitions among amorphous semiconductors such as a-Si, and transformations into metastable forms of the element that occur when its "expanded" clathrate polymorph is compressed.

Combined small- and wide-angle X-ray scattering (SAXS/WAXS), mechanical and thermal techniques have been used to follow the morphology evolution in a series of poly(ethylene terephthalate) (PET) multiwall carbon nanotube (MWCNT) composite films during quasi solid-state uniaxial deformation at low strain rates. Uniaxially deformed PET-MWCNT films displayed improved mechanical properties compared with unfilled PET films. SAXS/WAXS data revealed a well oriented lamellar structure for unfilled PET films. In contrast, the PET-MWCNT composites revealed a nanohybrid shish-kebab (NHSK) morphology, with reduced orientation and crystallinity. Mechanistically, this morphology development is attributed to the MWCNTs acting as shish for the epitaxial growth of PET crystallites. Furthermore, nucleation and crystal growth occurs in the PET matrix, but MWCNTs ultimately inhibit crystallite development and hinder a final lamellar structure developing. The results show unequivocally the role MWCNTs play as nanofillers, in the morphology development, thermal and mechanical properties in composite polymer films.

We have developed a method to understand the forces that pairs of cells exert upon each other on a surface. When exerting a force or torque on another object, a cell experiences an equal and opposite recoil force, and must therefore brace itself against its substrate. If the substrate is soft and elastic, then absorbing the recoil causes observable displacements of marker particles imbedded below its surface. We here describe a method of traction force microscopy, which can detect and analyze the recoil displacements. We validate our method using a clone of Breast Ductal Epithelial cells, (BDE's), that crawl and interact on collagen coated polyacrylamide substrates of different stiffness. For these cells, noise in the bead data causes random, or “phantom”, forces that fluctuate with standard deviation of approximately 10 nN. In cases where cells are touching, we universally observe significant tension forces that are usually aligned with the centroid-centroid axis of the cell pair. In contrast there are only a few isolated cases where shear forces or torques between BDE cells are above threshold. We also observe that the BDE's exert tension forces in two very different ways; first as part of a “grappling” process which brings the cell membranes into greater contact, and second as the basis for a “tug-of-war,” which has the opposite result. Grappling seems to happen only in the early stages as BDE's pull themselves into alignment. Later on, during the tug-of-war, the cell-cell tension grows and can reach peak values of over 200 nN. In addition, the cell-substrate adhesions near the contact zone are lost.

3086Background: Agenus AGEN2034 is a fully-human IgG4 monoclonal antibody antagonist targeting Programmed Cell Death Protein-1 (PD-1). The objective was to assess safety, MTD, pharmacokinetic (PK) ...

The high pressure collaborative access team (HPCAT) was established to advance cutting edge, multidisciplinary, high-pressure (HP) science and technology using synchrotron radiation at sector 16 of the Advanced Photon Source of Argonne National Laboratory. The integrated HPCAT facility has established four operating beamlines in nine hutches. Two beamlines are split in energy space from the insertion device (16ID) line, whereas the other two are spatially divided into two fans from the bending magnet (16BM) line. An array of novel X-ray diffraction and spectroscopic techniques has been integrated with HP and extreme temperature instrumentation at HPCAT. With a multidisciplinary approach and multi-institution collaborations, the HP program at the HPCAT has been enabling myriad scientific breakthroughs in HP physics, chemistry, materials, and Earth and planetary sciences.

The structural behavior of the pyrochlore Bi2Hf2O7 with varying temperature has been studied by powder neutron diffraction X-ray diffraction, and Raman scattering. The unit cell undergoes phase changes that are determined by diffraction methods to occur between α-, β-, γ- and δ-polymorphs at around 400, 550 and 900 °C. The δ-Bi2Hf2O7 polymorph corresponds to the ideal cubic pyrochlore phase. Three of the four polymorphs have previously been reported to occur for Bi2Sn2O7. The need to accommodate the active Bi3+ lone pair in the presence of large HfO6 octahedra results in an “icelike” ordering of Bi positions in Bi2Hf2O7 at room temperature. A similar sequence of phase transitions is observed at room temperature with increasing Ti4+ for Hf4+ substitution in the compositional series Bi2Hf2-xTixO7. The structure changes as the space available to the Bi3+ ion increases represent a gradual increase in disorder and symmetry.

(Figure Presented) Extreme chemistry: The carbon nitride imide C 2 N 2 (NH) is synthesized from the single-source precursor 1-cyanoguanidine under high-pressure and high-temperature conditions in a laser-heated diamond-anvil cell. Characterization of single crystals recovered at ambient conditions reveals that the new compound adopts a defect wurtzite structure (see picture). © 2007 Wiley-VCH Verlag GmbH & Co. KGaA.

We prepared samples of cubic γ-MoNx (x∼0.5) by high-pressure–high-temperature synthesis. N atom site occupancies within the defect rock salt structure were determined from time-of-flight neutron diffraction and powder X-ray diffraction data by Rietveld analysis. The results show that N atoms occupy only octahedral sites within the structure. The semi-metallic compound is a superconductor, with T c = 5.2 K determined by SQUID magnetometry. The compressibility of the material was determined by synchrotron X-ray diffraction measurements at high pressure in the diamond anvil cell. The vibrational density of states was studied by Raman scattering spectroscopy.

We report compressibilities measured by synchrotron X-ray diffraction and phonon spectra from Raman scattering at high pressure in the diamond anvil cell (DAC) for cubic transition metal nitrides TiN1−x , γ-Mo2N and VN x . The high-hardness metal nitride compounds have large values of the bulk modulus. B1-structured nitrides normally have no allowed first-order Raman spectra. However, they exhibit broad bands that reflect the vibrational density of states g(ω) associated with breakdown of q=0 selection rules because of the presence of N3− vacancies on anion sites. Peaks in g(ω) at low frequency are identified with the longitudinal and transverse acoustic (TA) branches. The maximum in the TA band is correlated with the superconducting transition temperature in these materials (T c). In situ Raman scattering measurements in the DAC thus permit predictions of the T c variation with pressure for cubic nitrides and isostructural carbide materials.

Solution phase reactions between tetrakisdimethylamidotitanium (Ti(NMe2)4) and ammonia yield precipitates with composition TiC0.5N1.1H2.3. Thermogravimetric analysis (TGA) indicates that decomposition of these precursor materials proceeds in two steps to yield rocksalt-structured TiN or Ti(C,N), depending upon the gas atmosphere. Heating to above 700 °C in NH3 yields nearly stoichiometric TiN. However, heating in N2 atmosphere leads to isostructural carbonitrides, approximately TiC0.2N0.8 in composition. The particle sizes of these materials range between 4–12 nm. Heating to a temperature that corresponds to the intermediate plateau in the TGA curve (450 °C) results in a black powder that is X-ray amorphous and is electrically conducting. The bulk chemical composition of this material is found to be TiC0.22N1.01H0.07, or Ti3(C0.17N0.78H0.05)3.96, close to Ti3(C,N)4. Previous workers have suggested that the intermediate compound was an amorphous form of Ti3N4. TEM investigation of the material indicates the presence of nanocrystalline regions

A Raman study of natural magnetite has been performed at high pressure up to 20 GPa. Upon compression, the vibrational spectra do not exhibit any changes, except for the continuous shift to higher frequencies. Vibrational modeling of the specific heat and entropy based on the modified Kieffer’s model allowed the estimation of the magnetic contribution to the thermodynamic properties of magnetite by comparison with published calorimetric measurements. High-pressure data provided information on the volume dependence of phonon modes of magnetite expressed by the mode Gruneisen parameters γiT. The volume dependence of vibrational modes of magnetite is described by the averaged value γ=1.33, weighted by the contribution of each mode to the total lattice specific heat. This value was employed for the calculation of the pressure-temperature dependence of heat capacity and entropy. The effect of the uniaxial stress on the compressional behavior and related thermodynamic parameters of magnetite was inferred from experiments conducted in hydrostatic and quasi-hydrostatic environments.

Raman spectroscopic study on magnetite (FeFe2O4): a new assignment for the vibrational spectrum.

Natural magnetite (Fe3O4) in the form of single crystal and powder was studied by laser Raman spectroscopy at various laser powers. The correlations between the power of the excitation laser, the temperature of the sampled spot and the degree of oxidation of magnetite were accurately established. In the course of the oxidation of the single crystal of magnetite, the first characteristic features of hematite appear at about 300 and 410 cm−1, at a temperature close to 240°C. This may explain the erroneous assignment of these modes to the intrinsic Raman modes of magnetite in some studies. For the finely powdered magnetite, which is much more easily prone to oxidation, the reaction mechanism proceeds via a metastable maghemite (γ-Fe2O3) before the final product hematite is formed. Three independent methods based on the quasi-harmonic approximation and on the ratio of the Stokes to anti-Stokes intensities were used to calculate the local temperature of the laser-heated spot. Temperature-induced shifts of phonon bands were also evaluated. The phonons shift at the following rates: A1g − 0.023(1) cm−1 K−1, T2g(2) − 0.030(2) cm−1 K−1, Eg − 0.019(5) cm−1 K−1 and T2g(1) − 0.00(1) cm−1 K−1. Copyright © 2003 John Wiley & Sons, Ltd.

3075 Background: AGEN1884 is a fully human IgG1 monoclonal antibody targeting the co-inhibitory protein cytotoxic T lymphocyte-associated protein 4 (CTLA-4). CTLA-4 blockade has been shown to augment T cell activation and proliferation, resulting in immune infiltration of the tumor and subsequent regression. Objectives: Assess the safety, maximum tolerated dose (MTD), and pharmacokinetic (PK) and pharmacodynamic (PD) characteristics of AGEN1884 in patients (pts) with advanced and refractory malignancies using a “3+3” trial design. Methods: Eleven pts have been enrolled and treated to date. AGEN1884 was administered intravenously q3w for 4 doses and then q12w. Three (0.1, 0.3 and 1 mg/kg) of six (3, 6 and 10 mg/kg) planned dose levels have been completed. Results: Five pts were accrued at 0.1 mg/kg dose level (2 were not DLT evaluable) and three pts each at doses of 0.3 mg/kg and 1 mg/kg. Median age was 56 years (range 26–70), ECOG 0–2, with a median of 4 (range 1–8) prior therapies. No DLT events have been observed thus far. Data from 5 pts were available for PK evaluation. Half-life of AGEN1884 post first dose was 8.8 and 9.6 days for 0.3 mg/kg and 0.1 mg/kg dose levels, respectively, as measured by ELISA. As of Jan 31, 2017, pts across cohorts were followed for a median of 6 weeks (range 0-28). Six pts (54.5%) have come off study due to disease progression, while 5 (45.5 %) remain on study. One confirmed partial response (80% reduction) by RECIST criteria was seen at 0.1 mg/kg in a patient with angiosarcoma. Conclusions: AGEN1884 is safe at 0.1 and 0.3 mg/kg dose levels. Dose escalation is ongoing and updated safety and PK data will be presented. Clinical trial information: NCT02694822.

We combine high-pressure x-ray diffraction, high-pressure Raman scattering, and optical microscopy to investigate a series of ($1\ensuremath{-}x$)Pb(Mg${}_{1/3}$Nb${}_{2/3}$)O${}_{3}$-$x$PbTiO${}_{3}$ (PMN-$x$PT) solid solutions ($x=0.2$, 0.3, 0.33, 0.35, 0.37, 0.4) in diamond anvil cells up to 20 GPa at 300 K. The Raman spectra show a peak centered at 380 cm${}^{\ensuremath{-}1}$ starting above 6 GPa for all samples, in agreement with previous observations. X-ray diffraction measurements are consistent with this spectral change indicating a structural phase transition; we find that the triplet at the pseudocubic (220) Bragg peak merges into a doublet above 6 GPa. Our results indicate that the morphotropic phase boundary region ($x=0.33\ensuremath{-}0.37$) with the presence of monoclinic symmetry persists up to 7 GPa. The pressure dependence of ferroelectric domains in PMN-0.32PT single crystals was observed using a polarizing optical microscope. The domain wall density decreases with pressure and the domains disappear at a modest pressure of 3 GPa. We propose a pressure-composition phase diagram for PMN-$x$PT solid solutions.

We have combined first-principles calculations and high-pressure experiments to study pressure-induced phase transitions in silicon nitride (Si${}_{3}$N${}_{4}$). Within the quasi-harmonic approximation, we predict that the $\ensuremath{\alpha}$ phase is always metastable relative to the $\ensuremath{\beta}$ phase over a wide pressure-temperature range. Our lattice vibration calculations indicate that there are two significant and competing phonon-softening mechanisms in the $\ensuremath{\beta}$-Si${}_{3}$N${}_{4}$, while phonon softening in the $\ensuremath{\alpha}$-Si${}_{3}$N${}_{4}$ is rather moderate. When the previously observed equilibrium high-pressure and high-temperature $\ensuremath{\beta}$ $\ensuremath{\rightarrow}$ $\ensuremath{\gamma}$ transition is bypassed at room temperature (RT) due to kinetic reasons, the $\ensuremath{\beta}$ phase is predicted to undergo a first-order structural transformation to a denser $P\overline{6}$ phase above 39 GPa. The estimated enthalpy barrier height is less than 70 meV$/$atom, which suggests that the transition is kinetically possible around RT. This predicted new high-pressure metastable phase should be classified as a ``postphenacite'' phase. Our high-pressure x-ray diffraction experiment confirms this predicted RT phase transition around 34 GPa. No similar RT phase transition is predicted for $\ensuremath{\alpha}$-Si${}_{3}$N${}_{4}$. Furthermore, we discuss the differences in the pressure dependencies of phonon modes among the $\ensuremath{\alpha}$, $\ensuremath{\beta}$, and $\ensuremath{\gamma}$ phases and the consequences on their thermal properties. We attribute the phonon modes with negative Gr\"uneisen ratios in the $\ensuremath{\alpha}$ and $\ensuremath{\beta}$ phases as the cause of the predicted negative thermal expansion coefficients (TECs) at low temperatures in these two phases, and predict no negative TECs in the $\ensuremath{\gamma}$ phase.

We combine high-pressure x-ray diffraction, high-pressure Raman scattering, and optical microscopic methods to investigate a series of PMN-xPT solid solutions (x=0.2, 0.3, 0.33, 0.35, 0.37, 0.4) in diamond anvil cells up to 20 GPa at 300 K. The Raman spectra show a new peak centered at 380 cm−1 above 6 GPa for all samples, consistent with previous observations. X-ray diffraction measurements are consistent with this spectral change indicating a structural phase transition. For example, we find that the triplet at the pseudocubic [220] Bragg peak merges into a doublet above 6 GPa. The analyzed results indicate that the morphotropic phase boundary (x=0.33 to 0.37) with monoclinic symmetry persists up to 7 GPa. The pressure dependence of ferroelectric domains in PMN-0.32PT single crystals was observed with a polarizing optical microscope. The domain wall density decreases with pressure and the domains disappears at modest pressure of 3 GPa. This indicates that the high pressure phase of PMN-PT is not a macroscopic polar state. We suggest a phase diagram for the PMN-xPT solid solutions.

Understanding cell migration and cell-cell interactions are key to understanding cell invasion, a critical step in the progression of breast cancer. Biochemical and mechanical cues of the extracellular matrix have been shown to play important roles in cell-matrix and cell-cell interactions. We have experimentally tested the combined influence of these cues to better understand cell motility, force generation, cell-cell interaction and assembly in an ‘in vitro’ breast cancer model. MCF-10A non-tumorigenic mammary epithelial cells were observed on surfaces with varying fibronectin ligand concentration and polyacrylamide gel rigidity. Our data shows that cell velocity is biphasic in both matrix rigidity and adhesiveness. The maximum in cell migration velocity occurs only at specific combination of substrate stiffness and ligand density. We found cell-cell interactions reduce migration velocity. However the traction forces cells exert onto the substrate increase linearly with both cues, with cell in pairs exerting higher maximum tractions observed over single cells. A relationship between force and motility shows a maximum in single cell velocity not observed in cell pairs. Cell-cell adhesion becomes strongly favored on softer gels with elasticity ≤ 1250 Pascals (Pa), implying an existence of a compliance threshold that promotes cell-cell over cell-matrix adhesion. Finally on gels with stiffness similar to pre- malignant breast tissue, 400Pa, cells undergo multi-cellular assembly and division into three-dimensional spherical aggregates on a two-dimensional surface.

The compressibility of an iron-bearing magnesite (Mg_(0.87)Fe^(2+)_(0.12)Ca_(0.01))CO_3 was determined by means of single crystal diffraction up to 64 GPa. Up to 49 GPa the pressure-evolution of the unit cell volume of the solid solution with 12% of Fe^(2+) can be described by a third-order Birch-Murnaghan equation of state with parameters V_0 = 281.0(5)A^3, K_0 = 102.8(3) GPa, K'_0 = 5.44. The spin pairing of the Fe^(2+) d-electrons occurs between 49 and 52 GPa, as evidenced by a discontinuous volume change. The transition pressure is increased by about 5 GPa compared with the iron end-member; an effect consistent with a cooperative contribution of adjacent clusters to the spin transition. The trend is, however, opposite in the periclase-wstite solid solution. Differences among the two structures, in particular in the Fe-Fe interactions, that might explain the different behavior are discussed.

The structural behavior of the pyrochlore Bi2Hf2O7 with varying temperature has been studied by powder neutron diffraction X-ray diffraction, and Raman scattering. The unit cell undergoes phase changes that are determined by diffraction methods to occur between α-, β-, γ- and δ-polymorphs at around 400, 550 and 900 °C. The δ-Bi2Hf2O7 polymorph corresponds to the ideal cubic pyrochlore phase. Three of the four polymorphs have previously been reported to occur for Bi2Sn2O7. The need to accommodate the active Bi3+ lone pair in the presence of large HfO6 octahedra results in an “icelike” ordering of Bi positions in Bi2Hf2O7 at room temperature. A similar sequence of phase transitions is observed at room temperature with increasing Ti4+ for Hf4+ substitution in the compositional series Bi2Hf2-xTixO7. The structure changes as the space available to the Bi3+ ion increases represent a gradual increase in disorder and symmetry.

[1] Thermodynamic analysis and synchrotron X-ray diffraction experiments aimed at the investigation of stability of magnetite were carried out in the pressure-temperature ranges 0–36 GPa and 300–800 K, respectively. Thermodynamic assessment shows that at 298 K, the equilibrium pressure for the breakdown of magnetite to hematite and wustite is 13.3 GPa, while pressure for the backward synthesis FeO + Fe2O3 h-Fe3O4 is between 35 and 47 GPa, depending on the choice of equation of state. The stability field for the mixture of oxides Fe2O3 + FeO narrows with temperature increase, reaching a maximum temperature of only ∼850 K at pressure 14.6 GPa. The calculations predict that the high-pressure phase of magnetite (h-Fe3O4) becomes unstable with respect to h-Fe2O3 + FeO at pressures higher than 50 GPa. The 298 K pressure-volume isotherm of magnetite derived from the compression experiment is given by KT = 217(7) GPa for the fixed K′0 = 4. The 1σ confidence ellipsoid shows large and negative correlations for the fit parameters KT, K′0, and V0. The thermodynamically predicted breakdown of magnetite to hematite and wustite was not observed, but the trace amounts of hematite detected in the sample assemblage may signify a presence of nucleation centers of breakdown products, the growth of which is kinetically hindered because of the energetic requirements for the reaction. The transformation of magnetite to a dense polymorph evolves gradually above 19 GPa. Rietveld refinement of the diffraction pattern of h-Fe3O4 is consistent with the CaTi2O4-type structure. The values of Gibbs formation energies at standard conditions for h-Fe3O4 and h-Fe2O3 were estimated to be −962 and −610 kJ mol−1, respectively. The standard state entropy of h-Fe3O4 is 172.4 J K−1 mol−1.

The existence of Ti3N4 was proposed as the first product of the thermal decomposition of precipitates obtained in ammonolysis reactions of titanium(IV) dialkylamides. The evidence is re-evaluated and further evidence is presented to demonstrate that these materials are probably TiN contaminated with carbon. However, this precursor system is demonstrated to be a good route to finely divided, nanocrystalline TiN powders.

Tabulated format of data presented in Figure 3 of the main manuscript

Tabulated format of data presented in Figure 4 of the main manuscript

Tabulated format of data presented in Figure 5 of the main manuscript