text:
\section{Introduction}

Dynamical arrest in soft matter can generally be divided into two classes, glasses and gels. Arrest is exhibited by a wide variety of systems,
including those which can be treated as spheres with attractions which include colloid-polymer mixtures \cite{poon2002} and protein solutions \cite{cardinaux2007, gibaud2009}. Dynamical arrest occurs upon either a global increase in density (vitrification) or arrested phase separation (gelation). In the latter case, phase separation is suppressed as the system undergoes arrest to form a non-equilibrium gel state, which we define as a percolating assembly of particles \cite{lu2008,manleyWyss2005} which do not relax on the experimental timescale.

In colloid-polymer mixtures, addition of sufficient polymer causes demixing into two or more phases \cite{asakura1954,vrij1976}. In a one-component description, the degrees of freedom of the polymers are formally integrated out, leading to an effective attraction between the colloidal particles whose range is fixed by the ratio of the polymer and colloid diameters $q_\textrm{R}$ \cite{dijkstra1999} and whose strength is set by the polymer concentration. To a reasonable approximation, polymer concentration plays the role of inverse temperature. The topology of the phase diagram is well-known: short-range interactions lead to only fluid-crystal phase coexistence, along with a metastable fluid-fluid binodal. However as the interaction range increases to $q_{\textrm{R}}\approx 0.3$, fluid-fluid phase separation produces a stable colloidal liquid and colloidal gas \cite{lekkerkerker1992,poon2002,ilett1995}.

While the topology of the phase diagram is well-known, the case of metastable amorphous states presents some challenges to theory and simulation \cite{taylor2012}. Smaller polymers lead to a shorter interaction range $q_\textrm{R}$, so that upon demixing, the colloids are closer together and thus the volume fraction of the colloid-rich phase $\phi_\textrm{c-r}$ is increased \cite{elliot1999,foffi2002}. Deep quenches (higher polymer concentration) may also raise $\phi_\textrm{c-r}$. During phase separation, if $\phi_\textrm{c-r}$ reaches volume fractions at which dynamical arrest occurs ($\phi_\textrm{c-r} \sim 0.57-0.59$), demixing is suppressed and a gel results \cite{lu2008,zaccarelli2007,tanaka2005}. In the absence of crystallisation, such a system is nonetheless metastable to colloidal liquid-gas coexistence. Fig. \ref{figPhaseDiagramSchematic} shows a schematic sketch of the effect of interaction range on the phase behaviour (ignoring crystal phases) \cite{foffi2005,lekkerkerker1992}.

Although such polydisperse dense (colloidal) liquids may be metastable to the formation of size-segregated crystals \cite{sollich2010}, to the best of our knowledge this has not been observed in experiments. Consequently, while most theoretical treatments necessarily consider the equilibrium monodisperse case where colloidal liquids are found up to $\phi_\textrm{c-r} \lesssim 0.5$ (a regime in which dynamical arrest is not expected),  the local volume fraction in the `arms' of a gel may be higher in experiments due to polydispersity. Although mean-field theories exist where the metastable gas-liquid binodal and spinodal can be calculated \cite{schmidt2002}, such predictions have limited accuracy for many polymer-colloid size ratios \cite{taylor2012}.

Previous work has largely focused on gelation in systems with short-range attractions, typically with polymer-colloid size ratios $q_{\textrm{R}} \lesssim 0.2$\cite{lu2008,poon1995,segre2001,ramakrishnan2002,verhaegh1999, royall2008} such that there is no equilibrium colloidal liquid phase. In such systems, gelation occurs upon crossing the metastable fluid-fluid spinodal\cite{lu2008,manleyWyss2005,ramakrishnan2002,royall2008}.  In contrast, phase separation and its arrest in colloid-polymer mixtures with medium-to-long range attractions, where there is a stable colloidal liquid phase, are much less understood.
Recent simulation\cite{testard2011} and experimental data\cite{lietorSantos2008,teece2011} suggest that a liquid-like colloid-rich phase exists, which grows continuously in length scale as the system ages.

For long-range ($q_{\textrm{R}} \gtrsim 0.3$) systems, we suggest two regimes of interest in relation to the gas-liquid binodal - shallow and deep quenches. For shallow quenches, the kinetics of phase separation in colloid-polymer mixtures is analogous to liquid-liquid demixing in molecular systems \cite{bailey2007}. The structural evolution can be described by the Cahn-Hilliard theory of spinodal decomposition \cite{cahn1959, jones2002}.  Several regimes are distinguished by the growth rate of the wavelength of density fluctuations. Immediately after quenching, a fastest-growing dominant mode $q_{\textrm{m}}$ appears with a wavelength $\lambda_{\textrm{m}}$, which exhibits time-dependent growth, with the power-law exponent changing from $1/3$ to 1 as the system evolves from the diffusive into the hydrodynamic coarsening regime. The characteristic domain size associated with the wavelength grows until it approaches the capillary length $\lambda_{\textrm{c}}=(\gamma / \Delta\rho g)^{1/2}$, where $\gamma$ is the interfacial tension and $\Delta\rho$ the density difference between the two phases, at which point any gravity-driven flow may rupture the bicontinuous structure \cite{aarts2005}.  Previous work on spinodal decomposition in colloid-polymer mixtures has shown that the crossover between diffusive and hydrodynamic regimes is broad and continuous, and both theory and experiment indicate that, depending on the importance of hydrodynamic interactions, the exponent may vary between 0.2 and 1.1 \cite{dhont1996,bailey2007}.

Quenching more deeply, the volume fraction of the colloidal liquid increases \cite{lekkerkerker1992,schmidt2002}.  The volume fraction of the colloid-rich phase may then approach $\phi \sim 0.58$, the point at which slow dynamics set in for hard spheres. Coarsening may therefore be suppressed and the bicontinuous network generated by the initial spinodal decomposition becomes partially or, in the limit of very short-range systems, even completely arrested on the experimental timescale \cite{tanaka2005}. The viscosity difference between the phases may be reminiscent of the viscoelastic phase separation proposed by Tanaka \cite{tanaka2005}.

\begin{figure}[h]
\centering
\includegraphics[width=80mm]{figPhaseDiagramSchematic}
\caption {Schematic phase diagram showing the effect of attractive range on the gas-liquid coexistence line and the intersection between the coexistence line and the glassy region. In short-range systems (a), the liquid-gas binodal is quite flat and upon quenching, the colloid-rich phase rapidly approaches a regime of glassy dynamics \cite{elliot1999}. Conversely, in longer-range systems (b), the volume fraction of the colloid-rich phase increases more gradually upon quenching.}
\label{figPhaseDiagramSchematic}
\end{figure}

In this work we explore these phase separation regimes in colloid-polymer mixtures with intermediate-to-long range attractions ($0.45 \leq q_\textrm{R} \leq 0.89$) using confocal microscopy.  Our data suggest that there is a continuous transition from gas-liquid phase separation to arrested phase separation (gelation) as a function of polymer concentration. The phase separation dynamics become increasingly slow as the system is quenched more deeply.  Experimental phase diagrams show that as the attractive range increases, the region where phase separation is uninterrupted by gelation expands. In addition, the mechanism of domain growth is studied in detail. We find that upon quenching, coarsening occurs predominately through enhanced particle mobility at the surface of the strands of the gel network.

\section{Materials and methods}
\subsection{Colloid-polymer mixture I: Emulsions + HEC}

Our first model system consisted of a low polydispersity emulsion of poly(dimethyl siloxane) (Silicone DC200 fluid 10cSt, Serva) dispersed in a refractive index-matched mixed solvent of 1,2-ethane diol (EG) and water. The emulsion was stabilized against aggregation by a combination of three commercial non-ionic surfactants (w/w ratio 1:0.417:0.015); tristyrylphenol ethoxylate, 16EO (Tanatex), PEO-PPO-PEO, $M_\textrm{w}$ 4950, 30\% PEO (Pluronic P103, BASF) and to give a small negative charge, the anionic surfactant sodium bis(2-ethyl 1-hexyl) sulfosuccinate (Aerosol OT, Cytec).  Small droplets (PDMS:surfactant 1:0.12) had a hydrodynamic radius $\sigma/2=142$ nm and a size polydispersity of 0.10, while large droplets (PDMS:surfactant 1:0.05) had a hydrodynamic radius  $\sigma/2=277$ nm and a size polydispersity of 0.18.  The index-matched continuous phase had a viscosity of 5.42 mPa
s $\pm$ 0.02 mPa s, as measured by capillary viscometry, a refractive
index of 1.396 at 543 nm, and a density of $\rho_{\textrm{c}} =1.067$ g cm$^{-3} \pm$
0.005 g cm$^{-3}$. The density of the PDMS oil is lower than the
continuous phase ($\rho_{\textrm{m}} = 0.934$ g cm$^{-3} \pm 0.006$ g cm$^{-3}$) so that the dispersions cream in a gravitational field. The density mismatch
of the oil is $\Delta\rho = \rho_\textrm{c} - \rho_\textrm{m} = 0.13\;\pm\;$ 0.01 g cm$^{-3}$. To screen out long-range electrostatic interactions and generate hard-sphere-like interactions between the emulsion drops we add 3 mM potassium chloride, which gives a Debye length of 6 nm.  A dye, Sudan Black, was also added to increase contrast between colloid-rich and colloid-poor phases such that the phase separation could be identified by eye.  Sudan Black preferentially adsorbs to the surface of the PDMS droplets, and so the colloid-rich phase appears dark and the colloid-poor phase light.

Hydroxyethylcellulose (HEC), which is a water-soluble non-ionic cellulose derivative, was used as the depletant.  Two molecular weights, of hydroxyethylcellulose were employed: Natrosol 250 M and Natrosol 250 HHX (Ashland-Aqualon), with molecular weights of $M_\textrm{w}=7.2\times10^{5}$ g mol$^{-1}$ and $M_\textrm{w}=1.3\times10^{6}$ g mol$^{-1}$ respectively.  Their estimated radii of gyration $R_{\textrm{g}}$ are 92 nm for Natrosol 250 M and 126 nm for Natrosol 250 HHX, as obtained by static light scattering.  Small droplets combined with Natrosol HHX gives a polymer-colloid size ratio, $q_{\textrm{R}} = (2 R_{\textrm{g}} / \sigma)$, of 0.89; small droplets with Natrosol M gives $q_{\textrm{R}}=0.65$; finally, large droplets with Natrosol HHX gives $q_{\textrm{R}}=0.45$.

Samples were prepared by first diluting a stock solution of the polymer with solvent, ensuring proper dispersion of the polymer. Then, solvent containing fluorescent rhodamine-B dye (Sigma Aldrich) was added such that the concentration of rhodamine-B was 0.02 gL$^{-1}$ in the aqueous phase for all samples. Finally, stock emulsion was added and the sample gently stirred for at least ten minutes before being quickly transferred to the imaging cell.  The start of the experiment ($t = 0$) was taken as the instant when stirring ceased.

\subsection{Colloid-polymer mixture II: PMMA + PS}

For our second system, we used poly(methyl methacrylate) (PMMA) core-shell particles\cite{bosma2002,campbell2002}, sterically stabilised with poly(12-hydroxy stearic acid) (PHSA), with a mean radius 416 nm and a polydispersity of 0.10, as determined by scanning electron microscopy.  Both the core and shell were labeled with fluorescent dyes: the core with coumarin and the shell with rhodamine-B.  The particles were suspended in a density-matched 78/22 (\%w/w)
mixture of cyclohexyl bromide and cis-decalin. 4 mM of tetrabutyl ammonium bromide was dissolved in the solvent mixture to screen electrostatic interactions and ensure hard-sphere-like behaviour of the colloids.  Depletion attractions were induced by addition of polystyrene (PS) as a non-adsorbing polymer.  The polymer molecular weight was $2.06\times10^{7}$ g mol$^{-1}$.  We estimate the polymer radius of gyration, $R_\textrm{g}$, to be 203 nm\cite{vincent1990}, such that the polymer-colloid size ratio $q_{\textrm{R}}$ was 0.49, which was comparable to that of the smallest size ratio in the emulsion droplet system.

\subsection{Confocal microscopy}
Confocal microscopy was used to study the temporal evolution of the bicontinuous network formed in our aqueous emulsion samples. A supporting frame was constructed to allow a light microscope (Zeiss, Axioskop S100) fitted with a confocal scanning head (Zeiss, LSM Pascal) to be mounted horizontally.  A laser wavelength of 532~nm was used to excite rhodamine molecules dissolved in the solvent, such that the background appears light and the emulsion droplets dark.  For clarity, we have inverted the micrographs pertaining to system I so that the colloid-rich phase appears bright and the colloid-poor phase dark. Emulsion-polymer dispersions (system I) were studied in large rectangular glass cuvettes with the front wall of the cell constructed from a 170 $\mu$m thick optical quality cover glass. The sealed cuvette had a square cross-section with an internal dimension of 13 mm, a height of 30 mm, and contained a small hole at the top of the cell through which the cell was filled.

For PMMA samples (system II), a conventionally mounted confocal microscope (Leica SP5 with resonant scanner) was used to image in the $xy$-plane and a laser with wavelength 488~nm was used to excite fluorescence from the coumarin-labelled core of the particles. 2D Images were collected at time intervals of $\delta t=$150-300 milliseconds over a total time period of 10-20 seconds, with typically 100-400 particles in each frame.  Data was averaged over 10-20 runs in order to improve statistics.

\subsection{Analysis}
To study the structural evolution quantitatively, length scales characteristic of the gel structure were extracted from the 2D-confocal images.  For an image of width $L$  taken at time $t$, we calculated the radially-averaged structure factor $S(q,t)$

\begin{equation}\label{eqn:S(q)}
    S(q,t) = \frac{1}{2 \pi q \Delta q} \int_{q \leq |\mathbf{q'}| \leq q + \Delta q} \mathrm{d}\mathbf{q'} \left < \tilde{I}(\mathbf{q'},t) \tilde{I}(-\mathbf{q'},t) \right >
\end{equation}

\noindent
where $\tilde{I}(\mathbf{q},t)$ is the 2D Fourier Transform (FT) of the image intensity $I(\mathbf{r},t)$ and $\Delta q = 2 \pi /L$.  The 2D Fourier transform displays a ring of high intensity at low $q$ which signifies the presence of a large characteristic length scale.  We characterise the dominant wavevector by the first moment $\langle q(t) \rangle$ of the structure factor, where

\begin{equation}
\langle q(t) \rangle = \int_{a}^{b} \mathrm{d}q \; qS(q,t) / \int_{a}^{b} \mathrm{d}q \;S(q,t)
\end{equation}

\noindent
with limits $a=0.02$ $\mu$m$^{-1}$ and $b=0.4$ $\mu$m$^{-1}$.  The dominant wavevector was then converted into a characteristic size $\lambda_{\textrm{c}}(t)=2\pi / \langle q(t) \rangle$.

In the PMMA system, the motion of the colloidal particles was tracked using modified versions of standard tracking routines\cite{crocker1996,royall2003}. Particles were separated into two groups: we define surface particles as those with $n=1-4$ neighbours throughout the image set, and bulk particles as ones with $n>4$.

In order for timescales to be compared directly in systems with different particle sizes and solvent viscosities, we quote all times in units of the characteristic Brownian time $\tau_{\textrm{B}}=3 \pi\eta_\textrm{L}\sigma^{3}/(4k_{\textrm{B}}T)$,  which is comparable to the time taken for a particle
to diffuse its own radius in a solvent of viscosity $\eta_\textrm{L}$.  For the PDMS emulsion system, the long time viscosity $\eta_\textrm{L}$ of the continuous phase was determined from  the diffusion constant of particles of known radius suspended in HEC solutions, using dynamic light scattering.  Viscosities $\eta_\textrm{L}$ were deduced from the measured diffusion constant using the Stokes-Einstein equation $D=k_\textrm{B}T/(3\pi\eta_\textrm{L} \sigma)$.  The concentration dependence of the viscosity was then fitted to the Martin equation \cite{teece2011Arxiv}, $\eta_\textrm{L}/\eta_{0}=1+[\eta]\cp\exp(k_{\textrm{H}}[\eta]\cp)$, where $\eta_\textrm{L}$ is the limiting low shear viscosity, $\eta_{0}$ is the solvent viscosity, $[\eta]$ is the intrinsic viscosity and $k_{\textrm{H}}$ is the Huggins constant. This equation is a reasonable prediction of polymer viscosity in the semi-dilute regime.  Regression gave fitted parameters of $[\eta]=0.30$ Lg$^{-1}$ and $k_{\textrm{H}}=1.2$ for the HHX grade, and $[\eta]=0.25$ Lg$^{-1}$, and $k_{\textrm{H}}=1.2$ for the lower molecular weight M grade.   The estimated Brownian times $\tau_{\textrm{B}}$ were between 0.1 s and 1.1 s, depending on the particle size, polymer molecular weight and polymer concentration.  In the PMMA system, the Brownian time was determined as $\tau_\textrm{B} = 0.7$ s.

\subsection{Phase diagrams}

Experimental phase diagrams at size ratios $q_{\textrm{R}}=0.45$ and $q_{\textrm{R}}=0.89$ were constructed for system I.  The overall colloid volume fraction in each sample was fixed at $\phi=0.2$ for all samples, and polymer concentration $\cp$ and hence quench depth was varied, such that all state points lie on a vertical line through the phase diagram.  Phase diagrams were obtained by allowing emulsion droplet samples shallowly quenched into the two-phase region to fully equilibrate, then measuring the colloid volume fraction in both phases using UV-visible spectroscopy to measure absorbance of Sudan Black at 600 nm, which was proportional to the droplet concentration. Fig. \ref{figUVVISPhaseDiagram} shows the phase diagrams we obtained. Note that we fix the overall $\phi$ in each sample. Thus our representation is approximately analogous to the polymer reservoir representation  \cite{lekkerkerker1992}, scaled by the free volume fraction for $\phi=0.2$.

The gas-liquid coexistence boundaries at $\phi=0.2$ were at $\cp=0.40$ gL$^{-1}$ and $\cp=0.60$ gL$^{-1}$, for $q_{\textrm{R}}=0.45$ and $q_{\textrm{R}}=0.89$ respectively.  As the time taken to equilibrate increases rapidly with polymer concentration, only shallow quenches were experimentally accessible for this method and we note that underestimation of the colloidal volume fraction of the colloid-rich phase cannot be ruled out.  Although the polymer concentrations used here are less than those used for the confocal experiments, extrapolations are sketched to show that the in the case of the smaller $q$, colloid-rich phase becomes dense with relatively shallow quenches after the coexistence line is crossed.  In contrast, the dense branch of the long-range system requires much deeper quenches to achieve comparable volume fraction.

\begin{figure*}[!htb]
\centering
\includegraphics[width=160mm]{figUVVISPhaseDiagram}
\caption{Phase diagrams at constant overall sample colloidal volume fraction $\phi=0.2$, (a)$q_{\textrm{R}}=0.45$ and (b)$q_{\textrm{R}}=0.89$.  In each phase diagram, the left-hand $y$-axis gives polymer concentrations rescaled in terms of the critical polymer concentration $C_{\textrm{crit}}$ as estimated from the phase diagram, and the right-hand $y$-axis gives polymer concentration in units of gL$^{-1}$.  Dotted lines show qualitative extrapolations of the phase boundary for deeper quenches.  Filled-in data points indicate data from phase separation experiments, unfilled data points show state points used for confocal imaging and Fourier lengthscale data.  Inset shows dependence of structural relaxation time $\tau_{\alpha}$ on colloid volume density for hard spheres. Shaded region in inset denotes the range of $\phi=0.57-0.59$ where the dynamics become very slow.
\label{figUVVISPhaseDiagram}}
\end{figure*}

Confocal microscopy was used to identify state points as either one- or two-phase and therefore to determine an estimate of the phase boundary for $q_{\textrm{R}}=0.65$ (system I) and also for system II. The phase boundary for $q_{\textrm{R}}=0.65$ was estimated as $\cp=1.00 \pm 0.20$ gL$^{-1}$ at $\phi=0.2$. Now the phase boundary for $q_{\textrm{R}}=0.65$ in units of gL$^{-1}$ does not lie between those corresponding $q_{\textrm{R}}=0.45$ and $q_{\textrm{R}}=0.89$. This is due to the different polymer molecular weights used to obtain these size ratios.
Similarly for system II, the phase boundary was estimated as $\cp=0.13 \pm 0.03$ gL$^{-1}$.

As the molecular weights and the solvency conditions of the polymers varied depending on $q_{\textrm{R}}$ and also on the system used, polymer concentrations are scaled by the polymer concentration at the (colloidal) gas-liquid critical point  $C_{\textrm{crit}}$, so as to allow direct comparisons to be made.  We estimate $C_{\textrm{crit}}$ by taking the polymer concentration at the liquid-gas phase boundary at $\phi=0.2$. Since our phase diagrams (Fig. \ref{figUVVISPhaseDiagram}) are plotted analogously to the polymer reservoir represenation, close to criticality the phase boundary is quite flat with respect to $\phi$ so that $\phi=0.2$ provides a reasonable estimate for the critical volume fraction $\phi_\textrm{crit}$ \cite{vink2005,royall2007}.  For system I, $C_{\textrm{crit}}$ = 0.40 gL$^{-1}$, 1.00 gL$^{-1}$ and 0.60 gL$^{-1}$ for $q_{\textrm{R}}=0.49$, $q_{\textrm{R}}=0.6$ and $q_{\textrm{R}}=0.89$ respectively.  For system II, $C_{\textrm{crit}}=0.13$ gL$^{-1}$.

\section{Results and discussion}

\subsection{Time evolution: observation}
At short times ($>$1 minute), spinodal decomposition patterns were observed. For very shallow quenches, in the case of system I (not density-matched), instead of gel formation, gravity-driven flow occurs almost immediately after a bicontinuous network forms, reminiscent of images showing the Rayleigh-Taylor instability in colloidal suspensions\cite{aarts2005,wysocki2010}.  Deeper quenches allow a stress-supporting network to form, where gel-like structures evolved $\sim$30 seconds after the sample mixing is ceased.  Shorter-range, strongly attractive samples produced a long-lived network of fine strands, whereas samples with longer-range attractions showed a continuously changing viscoelastic gel structure.

At a polymer concentration of $\cp/C_{\textrm{crit}}=1.20$ (Fig. \ref{figSpinodalZoomout}) in the density-matched  system II, liquid-gas phase separation progresses to completion over about two hours, with a percolating network of the colloid-rich phase coexisting with a colloidal gas, highly reminiscent of spinodal-like patterns also seen in the emulsion droplet system (I).

\begin{figure}[!htb]
\centering
\includegraphics[width=80mm]{figSpinodalZoom}
\caption{PMMA particles undergoing fluid-fluid phase separation, $\cp/C_{\textrm{crit}}=1.20$, $\phi=0.2$, $q_{\textrm{R}}=0.49$ showing characteristic spinodal pattern, with inset showing detail.  Scale bar in top left-hand corner indicates 25 $\mu$m; scale bar in inset indicates 5 $\mu$m. }
\label{figSpinodalZoomout}
\end{figure}

The rate of structural coarsening in system I can be represented by the growth of the characteristic domain size, as defined by the dominant wavevector of the 2D Fourier Transform of each confocal image.  Each data set exhibited a period of power law growth, where the rate of growth was given by the power law exponent.  Fig. \ref{figFitting} shows examples of how growth exponents were determined.

Data deviated from power law growth at very short times ($<100\tau_\textrm{B}$), where the domain size remained nearly constant.  This is indicative of a linear Cahn regime in early-stage spinodal decomposition and has previously been observed in other colloidal systems \cite{bhat2006,teece2011}.

\begin{figure}[!htb]
\includegraphics[width=80mm]{figFitting}
\caption{Examples of growth exponent fits for selected domain size growth datasets.
Here we plot the characteristic domain size $\lambda_\textrm{c}$ as a function of time.
$q_{\textrm{R}}=0.65$, $\phi=0.2$. Growth exponents of 0.229$\pm0.011$, 0.132$\pm0.006$, 0.060$\pm0.004$ respectively.}
\label{figFitting}
\end{figure}

The time-dependence of domain size $\lambda_\textrm{c}$ for varying polymer concentrations and size ratios is shown in Fig. \ref{figLengthscale}.  Growth exponents as a function of polymer concentration are shown in Fig. \ref{figGradients}.  At low polymer concentration, a regime of fluid-fluid phase separation was observed for all size ratios.  In this regime, the growth exponent is independent of quench depth for a given size ratio but ranged between 0.2 and 0.6 for the range of $q_{\textrm{R}}$ studied. This is consistent with previous work on phase separation in colloid-polymer mixtures where the growth exponent varied between 0.2 and 1.1 due to the broad crossover between diffusive and hydrodynamic regimes\cite{dhont1996,bailey2007}.

\subsection{Time evolution: connection to phase behaviour}
\label{subsectionTimeEvolution}
To gain insight into the phase separation dynamics, we assume these are related to the structural relaxation time in the colloid-rich phase. Neglecting the interfaces resulting from the bicontinuous network, the colloid-rich phase may be approximated by hard spheres at the same volume fraction, as the polymer concentration in this phase is low \cite{lekkerkerker1992}.  The structural relaxation time $\tau_{\alpha}$ in the colloid-rich phase can then be estimated, as a function of the volume fraction $\phi$, by the Vogel-Fulcher-Tammann equation\cite{brambilla2009, masri2009, flenner2010}:

\begin{equation}
\tau_{\alpha}(\phi) = \tau_{\infty} \exp\left[\frac{A}{(\phi_{0}-\phi)^{\delta}} \right]
\label{tau_alpha}
\end{equation}

\noindent Equation \ref{tau_alpha} is plotted in the inset in Fig. \ref{figUVVISPhaseDiagram} using parameters from ref. \cite{brambilla2009}, namely $A=2.25\times10^{-2}, \delta=2.0$ and $\phi_0=0.637$. As depicted in the inset to Fig. \ref{figUVVISPhaseDiagram}(b), when $\phi \sim 0.57-0.59$, relaxation times increase very strongly.

The dashed lines in Figs. \ref{figUVVISPhaseDiagram} (a) and (b) indicate the expected increase in volume fraction of the colloid-rich phase $\phi_\textrm{c-r}$ at the state points considered in our time-evolution (Fig. \ref{figLengthscale}). Our extrapolation suggests that, in the intermediate and slow phase separation regimes, the volume fraction of the colloid-rich phase reaches $\phi_\textrm{c-r}\sim0.57-0.59$, such that the dynamics of phase separation is limited by particle relaxation in the dense phase. In other words, the particle level dynamics become coupled to phase separation as a whole. Conversely, at weaker quenches where the volume fraction of the colloid-rich phase is not high enough to exhibit slow dynamics, $\tau_{\alpha}$ is very much less than the dynamics of phase separation. In short, our system exhibits two regimes of phase separation - `normal' and `viscoelastic'\cite{tanaka2000}.

This crossover between phase separation and gelation gives rise to an intermediate regime where phase separation still progresses to completion, but in contrast to ordinary fluid-fluid phase separation, the growth exponent decreases with increasing polymer concentration.  This regime is dominated by slow dynamics in the colloid-rich phase, where increasing densities result in a viscous yet still fluid state.  A corresponding increase in $\tau_{\alpha}$ can be seen, although in this regime $\tau_{\alpha}$ is still easily accessible on the experimental timescale.  These regimes are indicated in Fig. \ref{figGradients}.

The onset of gelation can be identified from the data by a decrease in the growth exponent during the imaging time, at $t\sim100$ seconds (which corresponds to around 1000$\tau_\textrm{B}$) as shown in Fig. \ref{figLengthscale}.  In these samples, phase separation is suppressed by gelation after the colloid-rich phase densifies to form a glass.  This type of behaviour has also been seen in simulations\cite{testard2011} of the Lennard-Jones system, as well as experiments on systems with short-range attractions\cite{lu2008}.  Quenching more deeply, the slow growth regime of characteristic domain size proceeds is quickly reaching after quenching and so the change in growth exponent becomes too fast to be experimentally accessible.

In the gel regime, the structure continues to coarsen, i.e. the growth exponent is non-zero.  This differs markedly from the behaviour of gels with short-range attractions and, at first glance, may appear paradoxical, as the gel structure is composed of a glassy network where particles are unable to rearrange.

\begin{figure}[!htb]
\centering
\includegraphics[width=80mm]{figLengthscale}
\caption {Here we plot the characteristic domain size $\lambda_\textrm{c}$, obtained from 2D-FFT of confocal images of system I, as a function of time. $\phi=0.2$, (a) $q_{\textrm{R}}=0.45$, (b) $q_{\textrm{R}}=0.65$, (c) $q_{\textrm{R}}=0.89$.  Indicated in (a-c) are estimated volume fractions in the colloid-rich phase $\phi_{\textrm{c-r}}$, as compared volume fraction at which hard spheres undergo the glass transition, $\phi_{\textrm{g}}$.
}
\label{figLengthscale}
\end{figure}

\begin{figure}[!htb]
\centering
\includegraphics[width=80mm]{figFFT_Gradients_Summary}
\caption{Growth exponent of domain sizes as a function of polymer concentration, $q_{\textrm{R}}=0.45 - 0.89$, $\phi=0.2$.  Dashed lines are a guide to the eye. Labels indicate behavioural regimes as follows: (a) Normal phase separation, (b)Intermediate 'slow' phase separation and (c) gelation.}
\label{figGradients}
\end{figure}

\subsection{Local dynamics}

We now address this apparent paradox by studying the motion of individual particles using
 experimental system II. We find that that particle mobility at the surface of the gel strand is enhanced in comparison to particles in the interior of the gel strand, such that occasional particle-hopping was observed at the surface of the gel strands even in gels that were `arrested'.

Dynamical heterogeneities became significant as the system approached gelation.  At a polymer concentration of $\cp/C_{\textrm{crit}}=2.40$, it was apparent that the system consisted of two particle populations, an effect previously observed in colloidal systems\cite{gao2007,puertas2004,royall2008}, and also for polymer glasses\cite{fakhraai2008}.  `Slow' particles were stuck in an arrested network, and `fast' particles, which were able to diffuse over a number of particle diameters, occupied surface sites on this network.  Mean square displacements of bulk and surface particles (Fig. \ref{figMSD}) show that they correspond to `slow' and `fast' particles respectively.  Sub-diffusive behaviour is observed for all particles, although this may be due to the relatively short imaging time.   Due to the experimental timescale, the extent of particle diffusion is limited, but there are indications that a plateau may be developing in the data for $\cp/C_{\textrm{crit}}=2.40$.  As quench depth increased, the number of `fast' particles decreased.  At a deep quench of $\cp/C_{\textrm{crit}}=9.70$, no fast particles were detected over a two-hour period.

\begin{figure}[h]
\centering
\includegraphics[width=80mm]{figMSD}
\caption{Mean square displacements for $\cp/C_{\textrm{crit}}=1.20$ and $\cp/C_{\textrm{crit}}=2.40$ in units of $\mu$m$^{2}$ and particle diameter $\sigma$, with particles grouped according to number of neighbours $n$. Dotted line shows diffusive linear growth of MSD.  $\phi=0.2$, $q_{\textrm{R}}=0.49$}
\label{figMSD}
\end{figure}

Some localised areas of the gel network surface exhibited greater particle mobility than others, and particles appear to rearrange cooperatively, an example of which is shown in Fig. \ref{figSingleParticle}.  It is possible that self-generated mechanical stress within the gel and the resulting deformation lowers the activation energy of particle-hopping in localised areas.  It has previously been proposed \cite{koyama2009} that self-generated stress builds up at local weak points within a transient gel network, thereby increasing particle mobility in small regions and providing a mechanism for gel collapse in arrested gels.

\begin{figure}[h]
\centering
\includegraphics[width=80mm]{figSingleParticleMotion}
\caption{Localised particle-hopping on surface of arrested gel network.  Magnified snapshots of an area (small box) are shown in the four larger boxes as a time-sequence.  The particles undergo a local re-arrangement over $\sim 500$ s, as indicated by the outlined particles. The snapshots are taken at $t=320$ s, 410 s, 420 s and 460 s after imaging began, which correspond to $460\tau_{\textrm{B}}$, $590\tau_{\textrm{B}}$, $600\tau_{\textrm{B}}$ and $660\tau_{\textrm{B}}$.
$\cp/C_{\textrm{crit}}=3.90$, $q_{\textrm{R}}=0.49$, $\phi=0.2$. Scale bar in top left-hand corner indicates 10 $\mu$m.}
\label{figSingleParticle}
\end{figure}

\section{Conclusions}

We have presented an experimental study of dynamics in phase-separating colloid-polymer mixtures with interaction range between 0.45 and 0.89.  Our data suggest that the crossover from phase separation to gelation is a continuous process as function of polymer concentration, with phase separation dynamics slowing gradually until arrest is reached.  By analysing the time growth of the domain size during phase separation, we observe a range of behaviour from liquid-gas phase separation at shallow quench depths to dynamic arrest and gelation at deep quenches.  Data from confocal imaging is supported by experimental equilibrium phase diagrams, in order to highlight the changes in dynamics with attractive range.  As the attractive range increases, the region of the phase diagram corresponding to phase separation becomes larger, and the crossover into gelation more gradual.

In addition, we find evidence of a mechanism of structural coarsening and domain growth in `arrested' gels, where rearrangements on the surface of the gel strand may continue despite a glassy, arrested state inside the gel strand, an effect which becomes more significant with increasing attractive range.

The dynamics of the colloid-rich phase are taken to be similar to hard spheres at the same estimated volume fraction. Under this assumption we find the dynamics of phase separation couple to the structural relaxation at the particle level in the colloid-rich phase upon deep quenches where slow dynamics set in. At weaker quenches, the phase separation dynamics decouple from the single-particle dynamics, and in this way we distinguish two modes of phase separation - `normal' and `viscoelastic'.  Further work could investigate this observation more closely.  In particular, a more accurate determination of the volume fraction of the colloid-rich phase would be desirable. While this may be tackled experimentally or by simulation, theoretical extensions of metastable liquid binodals and spinodals would be most helpful. While mean-field theory \cite{schmidt2002} is readily available for the range of volume fractions in the colloid-rich phase relevant to gelation ($\phi_\textrm{c-r}\gtrsim0.57-0.59$), especially for smaller size ratios, its accuracy may be limited \cite{taylor2012}. We hope to have raised the issue that colloid-polymer mixtures (and other model systems such as DNA-coated colloids \cite{geerts2012})frequently become involved in metastable liquid states at high volume fraction, and that treatment of such states with theories more sophisticated than mean-field (such as hierarchical reference theory \cite{loVerso2006}) or
self-consistent Ornstein-Zernike approximation \cite{foffi2002} may prove invaluable if extended to higher colloid volume fraction for a variety of interction ranges.

\section*{Acknowledgements}

This work was supported jointly by Bayer CropScience and the UK Engineering and Physical Sciences Research Council through the award of an Industrial CASE award to IZ. CPR acknowledges the Royal Society for financial support and EPSRC grant code EP/H022333/1 for
provision of equipment used in this work

\footnotesize{

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\bibitem[Poon(2002)]{poon2002}
W.~C.~K. Poon, \emph{J Phys : Condens Matter}, 2002, \textbf{14}, R859\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Cardinaux \emph{et~al.}(2007)Cardinaux, Gibaud, Stradner, and
  Schurtenberger]{cardinaux2007}
F.~Cardinaux, T.~Gibaud, A.~Stradner and P.~Schurtenberger, \emph{Phys Rev
  Lett}, 2007, \textbf{99}, 118301\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Gibaud and Schurtenberger(2009)]{gibaud2009}
T.~Gibaud and P.~Schurtenberger, \emph{J. Phys.: Condens. Matter}, 2009,
  \textbf{21}, 322201\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Lu \emph{et~al.}(2008)Lu, Zaccarelli, Ciulla, Schofield, Sciortino,
  and Weitz]{lu2008}
P.~J. Lu, E.~Zaccarelli, F.~Ciulla, A.~B. Schofield, F.~Sciortino and D.~A.
  Weitz, \emph{Nature}, 2008, \textbf{453}, 499--503\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Manley \emph{et~al.}(2005)Manley, Wyss, Miyazaki, Conrad, Trappe,
  Kaufman, Reichman, and Weitz]{manleyWyss2005}
S.~Manley, H.~M. Wyss, K.~Miyazaki, J.~C. Conrad, V.~Trappe, L.~J. Kaufman,
  D.~R. Reichman and D.~A. Weitz, \emph{Phys Rev Lett}, 2005, \textbf{95},
  238302\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Asakura and Oosawa(1954)]{asakura1954}
S.~Asakura and F.~Oosawa, \emph{J Chem Phys}, 1954, \textbf{22},
  1255--1256\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Vrij(1976)]{vrij1976}
A.~Vrij, \emph{Pure Appl. Chem.}, 1976, \textbf{48}, 471--483\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Dijkstra \emph{et~al.}(1999)Dijkstra, Brader, and Evans]{dijkstra1999}
M.~Dijkstra, J.~M. Brader and R.~Evans, \emph{J. Phys.: Condens. Matter}, 1999,
  \textbf{11}, 10079--10106\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Lekkerkerker \emph{et~al.}(1992)Lekkerkerker, Poon, Pusey, Stroobants,
  and Warren]{lekkerkerker1992}
H.~N.~W. Lekkerkerker, W.~C.-K. Poon, P.~N. Pusey, A.~Stroobants and P.~B.
  Warren, \emph{EPL (Europhysics Letters)}, 1992, \textbf{20}, 559\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Ilett \emph{et~al.}(1995)Ilett, Orrock, Poon, and Pusey]{ilett1995}
S.~M. Ilett, A.~Orrock, W.~C.~K. Poon and P.~N. Pusey, \emph{Phys Rev E}, 1995,
  \textbf{51}, 1344 LP -- 1352\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Taylor \emph{et~al.}(2012)Taylor, Evans, and Royall]{taylor2012}
S.~Taylor, R.~Evans and C.~P. Royall, \emph{CondMat ArXiV}, 2012,
  1205.0072\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Elliot and Hu(1999)]{elliot1999}
J.~R. Elliot and L.~Hu, \emph{J. Chem. Phys.}, 1999, \textbf{110},
  3043--3048\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Foffi \emph{et~al.}(2002)Foffi, McCullagh, Lawlor, Zaccarelli, ,
  Dawson, Sciortino, Pini, and Stell]{foffi2002}
G.~Foffi, G.~D. McCullagh, A.~Lawlor, E.~Zaccarelli, , K.~A. Dawson,
  P.~Sciortino, F.and~Tartaglia, D.~Pini and G.~Stell, \emph{Phys, Rev. E},
  2002, \textbf{65}, 031407\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Zaccarelli(2007)]{zaccarelli2007}
E.~Zaccarelli, \emph{J Phys : Condens Matter}, 2007, \textbf{19}, 323101\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Tanaka \emph{et~al.}(2005)Tanaka, Nishikawa, and Koyama]{tanaka2005}
H.~Tanaka, Y.~Nishikawa and T.~Koyama, \emph{J Phys : Condens Matter}, 2005,
  \textbf{17}, L143\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Foffi \emph{et~al.}(2005)Foffi, Michele, Sciortino, and
  Tartaglia]{foffi2005}
G.~Foffi, C.~D. Michele, F.~Sciortino and P.~Tartaglia, \emph{Phys. Rev.
  Lett.}, 2005, \textbf{94}, 078301\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Sollich and Wilding(2010)]{sollich2010}
P.~Sollich and N.~B. Wilding, \emph{Phys. Rev. Lett.}, 2010, \textbf{104},
  118302\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Schmidt \emph{et~al.}(2002)Schmidt, Loewen, Brader, and
  Evans]{schmidt2002}
M.~Schmidt, H.~Loewen, J.~M. Brader and R.~Evans, \emph{J. Phys.: Condens.
  Matter}, 2002, \textbf{14}, 9353--9382\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Poon \emph{et~al.}(1995)Poon, Pirie, and Pusey]{poon1995}
W.~C.~K. Poon, A.~D. Pirie and P.~N. Pusey, \emph{Faraday Discuss}, 1995,
  \textbf{101}, 65 -- 76\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Segr\`e \emph{et~al.}(2001)Segr\`e, Prasad, Schofield, and
  Weitz]{segre2001}
P.~N. Segr\`e, V.~Prasad, A.~B. Schofield and D.~A. Weitz, \emph{Phys Rev
  Lett}, 2001, \textbf{86}, 6042--6045\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Ramakrishnan \emph{et~al.}(2002)Ramakrishnan, Fuchs, Schweizer, and
  Zukoski]{ramakrishnan2002}
S.~Ramakrishnan, M.~Fuchs, K.~S. Schweizer and C.~F. Zukoski, \emph{J. Chem.
  Phys.}, 2002, \textbf{116}, 2201--2212\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Verhaegh \emph{et~al.}(1999)Verhaegh, Asnaghi, and
  Lekkerkerker]{verhaegh1999}
N.~A.~M. Verhaegh, D.~Asnaghi and H.~N.~W. Lekkerkerker, \emph{Physica A:
  Statistical and Theoretical Physics}, 1999, \textbf{264}, 64 -- 74\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Royall \emph{et~al.}(2008)Royall, Williams, Ohtsuka, and
  Tanaka]{royall2008}
C.~Royall, S.~R. Williams, T.~Ohtsuka and H.~Tanaka, \emph{Nat Mater}, 2008,
  \textbf{7}, 556--561\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Testard \emph{et~al.}(2011)Testard, Berthier, and Kob]{testard2011}
V.~Testard, L.~Berthier and W.~Kob, \emph{Phys Rev Lett}, 2011, \textbf{106},
  125702\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Lietor-Santos \emph{et~al.}(2008)Lietor-Santos, Kim, Lu,
  Fernandez-Nieves, and Weitz]{lietorSantos2008}
J.~J. Lietor-Santos, C.~Kim, P.~J. Lu, A.~Fernandez-Nieves and D.~A. Weitz,
  \emph{The European Physical Journal E}, 2008,  1--\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Teece \emph{et~al.}(2011)Teece, Faers, and Bartlett]{teece2011}
L.~J. Teece, M.~A. Faers and P.~Bartlett, \emph{Soft Matter}, 2011, \textbf{7},
  1341--1351\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Bailey \emph{et~al.}(2007)Bailey, Poon, Christianson, Schofield,
  Gasser, Prasad, Manley, Segre, Cipelletti, Meyer, Doherty, Sankaran,
  Jankovsky, Shiley, Bowen, Eggers, Kurta, Lorik, Pusey, and Weitz]{bailey2007}
A.~E. Bailey, W.~C.~K. Poon, R.~J. Christianson, A.~B. Schofield, U.~Gasser,
  V.~Prasad, S.~Manley, P.~N. Segre, L.~Cipelletti, W.~V. Meyer, M.~P. Doherty,
  S.~Sankaran, A.~L. Jankovsky, W.~L. Shiley, J.~P. Bowen, J.~C. Eggers,
  C.~Kurta, T.~Lorik, P.~N. Pusey and D.~A. Weitz, \emph{Phys Rev Lett}, 2007,
  \textbf{99}, 205701\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Cahn(1965)]{cahn1959}
J.~W. Cahn, \emph{J Chem Phys}, 1965, \textbf{42}, 93--99\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Jones(2002)]{jones2002}
R.~A.~L. Jones, \emph{Soft Condensed Matter}, Oxford University Press,
  2002\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Aarts \emph{et~al.}(2005)Aarts, Dullens, and Lekkerkerker]{aarts2005}
D.~G. A.~L. Aarts, R.~P.~A. Dullens and H.~N.~W. Lekkerkerker, \emph{New
  Journal of Physics}, 2005, \textbf{7}, 40\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Dhont(1996)]{dhont1996}
J.~K.~G. Dhont, \emph{J Chem Phys}, 1996, \textbf{105}, 5112--5125\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Bosma \emph{et~al.}(2002)Bosma, Pathmamanoharan, de~Hoog, Kegel, van
  Blaaderen, and Lekkerkerker]{bosma2002}
G.~Bosma, C.~Pathmamanoharan, E.~H. de~Hoog, W.~K. Kegel, A.~van Blaaderen and
  H.~N. Lekkerkerker, \emph{J Colloid Interface Sci}, 2002, \textbf{245}, 292
  -- 300\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Campbell and Bartlett(2002)]{campbell2002}
A.~Campbell and P.~Bartlett, \emph{J. Coll. Interf. Sci.}, 2002, \textbf{256},
  325--330\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Vincent(1990)]{vincent1990}
B.~Vincent, \emph{Colloids and Surfaces}, 1990, \textbf{50}, 241 -- 249\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Crocker and Grier(1996)]{crocker1996}
J.~C. Crocker and D.~G. Grier, \emph{J Colloid Interface Sci}, 1996,
  \textbf{179}, 298 -- 310\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Royall \emph{et~al.}(2003)Royall, Leunissen, and van
  Blaaderen]{royall2003}
C.~P. Royall, M.~E. Leunissen and A.~van Blaaderen, \emph{J. Phys.: Condens.
  Matter}, 2003, \textbf{15}, S3581--S3596\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Teece and Bartlett(2011)]{teece2011Arxiv}
L.~Teece and P.~Bartlett, arXiv:1109.4893v1 [cond-mat.soft]\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Vink and Schmidt(2005)]{vink2005}
R.~L.~C. Vink and M.~Schmidt, \emph{Phys. Rev. E}, 2005, \textbf{71},
  051406\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Royall \emph{et~al.}(2007)Royall, Aarts, and Tanaka]{royall2007}
C.~P. Royall, D.~G. A.~L. Aarts and H.~Tanaka, \emph{Nat Phys}, 2007,
  \textbf{3}, 636--640\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Wysocki \emph{et~al.}(2010)Wysocki, Royall, Winkler, Gompper, Tanaka,
  van Blaaderen, and Lowen]{wysocki2010}
A.~Wysocki, C.~P. Royall, R.~G. Winkler, G.~Gompper, H.~Tanaka, A.~van
  Blaaderen and H.~Lowen, \emph{Faraday Discuss.}, 2010, \textbf{144},
  245--252\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Bhat \emph{et~al.}(2006)Bhat, Tuinier, and Schurtenberger]{bhat2006}
S.~Bhat, R.~Tuinier and P.~Schurtenberger, \emph{J Phys : Condens Matter},
  2006, \textbf{18}, L339\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Brambilla \emph{et~al.}(2009)Brambilla, El~Masri, Pierno, Berthier,
  Cipelletti, Petekidis, and Schofield]{brambilla2009}
G.~Brambilla, D.~El~Masri, M.~Pierno, L.~Berthier, L.~Cipelletti, G.~Petekidis
  and A.~B. Schofield, \emph{Phys. Rev. Lett.}, 2009, \textbf{102},
  085703\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Masri \emph{et~al.}(2009)Masri, Brambilla, Pierno, Petekidis,
  Schofield, Berthier, and Cipelletti]{masri2009}
D.~E. Masri, G.~Brambilla, M.~Pierno, G.~Petekidis, A.~B. Schofield,
  L.~Berthier and L.~Cipelletti, \emph{Journal of Statistical Mechanics: Theory
  and Experiment}, 2009,  P07015\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Flenner and Szamel(2010)]{flenner2010}
E.~Flenner and G.~Szamel, \emph{Phys. Rev. Lett.}, 2010, \textbf{105},
  217801\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Tanaka(2000)]{tanaka2000}
H.~Tanaka, \emph{J Phys : Condens Matter}, 2000, \textbf{12}, R207\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Gao and Kilfoil(2007)]{gao2007}
Y.~Gao and M.~L. Kilfoil, \emph{Phys. Rev. Lett.}, 2007, \textbf{99},
  078301\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Puertas \emph{et~al.}(2004)Puertas, Fuchs, and Cates]{puertas2004}
A.~M. Puertas, M.~Fuchs and M.~E. Cates, \emph{The Journal of Chemical
  Physics}, 2004, \textbf{121}, 2813--2822\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Fakhraai and Forrest(2008)]{fakhraai2008}
Z.~Fakhraai and J.~A. Forrest, \emph{Science}, 2008, \textbf{319},
  600--604\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Koyama \emph{et~al.}(2009)Koyama, Araki, and Tanaka]{koyama2009}
T.~Koyama, T.~Araki and H.~Tanaka, \emph{Phys Rev Lett}, 2009, \textbf{102},
  065701\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Geerts and Eiser(2010)]{geerts2012}
N.~Geerts and E.~Eiser, \emph{Soft Matter}, 2010, \textbf{6}, 4647--4660\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\bibitem[Lo~Verso \emph{et~al.}(2006)Lo~Verso, Vink, Pini, and
  Reatto]{loVerso2006}
F.~Lo~Verso, R.~L.~C. Vink, D.~Pini and L.~Reatto, \emph{Phys. Rev. E}, 2006,
  \textbf{73}, 061407\relax
\mciteBstWouldAddEndPuncttrue
\mciteSetBstMidEndSepPunct{\mcitedefaultmidpunct}
{\mcitedefaultendpunct}{\mcitedefaultseppunct}\relax
\unskip.}
\end{mcitethebibliography}
}

\end{document}

redpajama_set_name: RedPajamaArXiv


text:
package fix

import (
	"github.com/mitchellh/mapstructure"
)

// FixerParallelsDeprecations removes "parallels_tools_host_path" from a
// template in a Parallels builder and changes "guest_os_distribution" to
// "guest_os_type", possibly overwriting any existing "guest_os_type"
type FixerParallelsDeprecations struct{}

func (FixerParallelsDeprecations) Fix(input map[string]interface{}) (map[string]interface{}, error) {
	// The type we'll decode into; we only care about builders
	type template struct {
		Builders []map[string]interface{}
	}

	// Decode the input into our structure, if we can
	var tpl template
	if err := mapstructure.Decode(input, &tpl); err != nil {
		return nil, err
	}

	for _, builder := range tpl.Builders {
		builderTypeRaw, ok := builder["type"]
		if !ok {
			continue
		}

		builderType, ok := builderTypeRaw.(string)
		if !ok {
			continue
		}

		if builderType != "parallels-iso" && builderType != "parallels-pvm" {
			continue
		}

		_, ok = builder["parallels_tools_host_path"]
		if ok {
			delete(builder, "parallels_tools_host_path")
		}

		guestOsDistribution, ok := builder["guest_os_distribution"]

		if ok {
			builder["guest_os_type"] = guestOsDistribution
			delete(builder, "guest_os_distribution")
		}
	}

	input["builders"] = tpl.Builders
	return input, nil
}

func (FixerParallelsDeprecations) Synopsis() string {
	return `Removes deprecated "parallels_tools_host_path" from Parallels builders
	and changes "guest_os_distribution" to "guest_os_type".`
}

redpajama_set_name: RedPajamaGithub


text:
Q: Google OAuth2 asking for "offline access" I'm using the Microsoft.Owin.Security.Google (version 3.0.1) middlware to provide Google OAuth to my app.
It's configured like so:
app.UseGoogleAuthentication(new GoogleOAuth2AuthenticationOptions
{
    AuthenticationType = "Google",
    Caption = "Google",
    SignInAsAuthenticationType = signInAsType, // "idsrv.external"
    ClientId = "xxx.apps.googleusercontent.com",
    ClientSecret = "xxx"
});

Pretty simple stuff. I'm using IdentityServer as the MW to issue the claims.
When i first authenticate the user with Google, Google asks for the following consent from the user:

Which makes total sense, as i'm requesting openid profile email scopes in the URL:

https://accounts.google.com/o/oauth2/auth?scope=openid profile email&response_type=code&redirect_uri=https://localhost:44301/core/signin-google&state=xxx&client_id=111.apps.googleusercontent.com&hl=en-GB&from_login=1&as=-25fb4219b2997893&authuser=0

I then accept, and all works well.
Now, after i logout, then re-authenticate again - from now on Google keeps asking me for "offline access":

I've not asked for offline access scope, so confused why Google is asking for this?
Confirmed the URL looks fine:

https://accounts.google.com/o/oauth2/auth?scope=openid profile email&response_type=code&redirect_uri=https://localhost:44301/core/signin-google&state=xxx&client_id=111.apps.googleusercontent.com&hl=en-GB&from_login=1&as=676f55265a78c036&authuser=0

So exactly the same URL as the first request.
I have tried:

*

*Turned on Google+ API in API console

*Tried adding &prompt=auto (causes error "Invalid parameter value for prompt: Invalid prompt: auto")

*Tried adding access_type=online (even though this is the default, if not provided).

*Tried adding approval_prompt=auto
None of those techniques have worked.
Any ideas?

A: Appeared to be localhost issue. Once deploy to server, worked fine :/

A: The offline_access scope value requests an OAuth 2.0 refresh token.
If you're not requesting this, then it sounds like something built into the OWIN Google component or the Google API.
You can read more about the offline access scope here: http://openid.net/specs/openid-connect-core-1_0.html#OfflineAccess

redpajama_set_name: RedPajamaStackExchange


text:
Umma
Umma (Suméria)
Umma - diversas espécies de libelinhas da família Calopterygidae
Umma saphirina
Umma femina
Umma declivium

Desambiguação

redpajama_set_name: RedPajamaWikipedia


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In celebration of Independance Day we dressed this Alox-SAK with its unique tool-combination (please notice the Phillips-screwdriver) in the appropiate national colors.
Dieser Umbau ist sowohl eine Reminiszens wie auch eine Weiterentwicklung des Electrician Duo Modells.
Ausgestattet sowohl mit Haken- wie auch mit Kabelklinge weist dieses Messer (natürlich abgesehen von der Schere!) eine Werkzeugkombination auf, die es leider nie in Produktion geschafft hat. Abgerundet wird das Erscheinungsbild durch blaue Alox-Schalen im Kontrast mit roten Zwischenplatinen.
This Mod is a reminiscence as well as a derivative of the Electrician Duo model.
Equipped with both pruner- and small electricians blade this SAK shows a tool-combination (besides the scissors of course!) which has alas never come to regular production. This outfit is topped off with blue Alox scales contrasted with red liners.


We Will Mourn You 'Til We Join You!
Oneal was born November 13th 1988; Oneal would be 17 years old today. He has 3 brothers and one sister. He was kind, fun-loving and yes a prankster. He loved pulling fast ones on friends and family alike, then fashing that beautiful smile that will be missed. He was coming into his own. Doing well in school. Beginning a new job in school. He was lovingly called "stank" by Mom, and "Gentle Giant" by Grandma. He will be forever loved and missed by friends and family alike!
Oneal was hit by a school bus January 3rd of 2005, on his way to school the beginning of the New Year. He was excited and had many new goals and plans ahead of him. He was in a coma for three days until God, who knows best called him home.


Our topic for the month for all of the Mother Goose Time Blog Ambassadors is science in Mother Goose Time. There are many different ways that Mother Goose Time entwines science into everyday learning. You can visit their website for a full explanation of how they add science into their curriculum.
Each of the monthly topics we have done so far have either been about a science topic or geography topic. For example this month we are learning about the Ocean, each day we learn about a different animal that is found in the ocean, or different concepts based around the Ocean theme. Last month the kids learned about Outer Space, and each day they learned about a different space concept, planet, etc. During the month the kids learn such a large range of skills it is really quite amazing.
On top of the fact that Mother Goose Time themes are usually based on a science concept in general, they also include a monthly science experiment on a card for easy filing.
This month, for example the kids did a science experiment about sweet and salty water because they are learning about the ocean. The experiment really showed the kids just what the ocean tastes like, which is wonderful because my kids have only experienced the fresh water great lakes so they really had no clue.
We also have both of the boys chart their before observations as well as the science experiment results and keep them in our science journals.
Here is one of our activities during our daily school, the boys are comparing and contrasting a tortoise and a sea turtle. Then we went over the facts about both of them that are on the back of the cards.
To find some great science experiments check out my Pinterest Science board, there are many great ideas there.
Follow Mama Of Many Blessings's board Science on Pinterest.
Disclaimer: As a Mother Goose Time Blog Ambassador I am provided with their monthly curriculum and writing prompts to share with my viewers. I am not compensated in any other way, and all opinions are the honest opinions of my children or myself. Please read my full disclosure policy for more information.


According to recent research, a high proportion of Australians aged over 50 are vulnerable to catching tetanus and diphtheria.
Tetanus, by the way, is caused by the toxin from a bacterial infection usually in a soil-contaminated skin wound. It's a terrible and often fatal disease starting with muscle spasms in the jaw and face, called lockjaw, then spreading.
Diphtheria is also a bacterial infection but of the nose and throat and sometimes the skin. In the throat a membrane can grow obstructing breathing and the diphtheria toxin can poison the heart, kidneys and brain. About 10 per cent of sufferers die.
So it doesn't sound good that 50-year-olds and upwards may be at risk. The study was a large sample of the population and found that 40 per cent of the people tested over the age of 50 were susceptible to diphtheria. The figure for tetanus was 25 per cent although in women over 70, 60 per cent were vulnerable.
All this supports the recommendation that everyone over 50 should receive a booster dose of tetanus and diphtheria immunisation unless they've been vaccinated in the past five years. If you've never been immunised, you'll need to have a course of immunisation from scratch.
Author: Gidding HF et al. Immunity to diphtheria and tetanus in Australia: a national serosurvey.


Whole-plant moisture and the plant's maturity at harvest affect corn silage quality, according to Kevin Sedivec, North Dakota State University Extension rangeland management specialist.
Corn should be harvested for silage at a moisture content of 65 to 70 percent when using a horizontal bunker. If too wet - above 70 percent - yield potential is reduced and seepage will occur, resulting in the undesirable presence of clostridia bacteria fermentation.
Clostridia bacteria are very inefficient, converting forage sugars and organic acids into butyric acid, carbon dioxide and ammonia. Silage with these bacteria loses dry matter, creates a foul smell due to the butyric acid, and has a higher pH, and poor forage quality and palatability.
Seepage results in a loss of nutrients that can be harmful to the environment and can allow feed to freeze during the winter.
Making silage when the corn is too dry results in poor packing, inadequate air exclusion, poor fermentation and heating. Dry silage creates higher levels of spoilage and low bunk life.
So, approximately how much water is in your standing corn? This year was classified as an earlier maturing year for corn, which was drying faster than normal due to dry conditions in late July and August.
Corn with the entire plant still green, tasseled and having two cobs in the R2 kernel stage (early kernel, no denting and no milk) was at 77.4 percent water content.
Drought-stressed corn with the bottom three to four leaves that were brown tested at 76.5 percent water content. The plants had one cob in the R2 kernel stage.
Drought-stressed corn with the bottom four to seven leaves that had turned brown and no cobs had a water content of 67.9 percent.
"Based on these findings, drought-stressed corn with the bottom four to seven leaves brown and dry was at the proper moisture content for silage fermentation," Sedivec says. "This silage would have no cobs and would be lower in production and energy content.
He advises that when corn is not stressed by drought, producers should make silage when the corn is at the dent kernel and approximately 75 percent milk stage.
He recommends producers start testing their corn fields for water content once the kernel reaches the dent stage and drought stress is not present. Once they have determined the percent of moisture, they need to be aware that whole-plant moisture has an average dry-down rate of 0.5 percent per day.
Visit NDSU Extension's "Harvesting, Storing and Feeding High-moisture Corn" publication at https://tinyurl.com/High-moistureCorn for more information.


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Moscow – An antisemitic caricature from the Third Reich appeared on one of the bookshelves of the "Republika Kenizny Magazine" bookstore.
The general public was informed of the "creative imagination" of the store's employees by a well-known Russian blogger, Rustem Adgamov, who wrote about it on his page. "In the Republic of Kenizny they think that this must be a brilliant joke," he wrote.


text:
MSM Spotlight:
Classical pianist Gabriela Fahnenstiel (MM '19) and jazz guitarist Michail Tsiftsis (MM '20)
Gabriela and Michail are taking part in the International Students' Concert and Live Webcast in Miller Recital Hall on Tuesday, April 9 at 7:30 PM. This annual event features MSM students from around the world, performing works by composers from their home countries.
Gabriela and Michail talk about this week's performance and why they're happy to be at Manhattan School of Music.
Watch live webcast!
Why are you excited about this concert?
Michail: I'm looking forward to performing with my fellow jazz musicians and international students. This is a special concert because it showcases the incredible talent of students who come to the United States specifically to study at MSM.
Gabriela: Music, by its nature, is international. I think it is wonderful that MSM dedicates a concert to pieces from our home countries, showing the diversity of music and of the school!
Tell us about a piece that you will be performing.
Gabriela: I'll be playing the first movement of Mendelssohn's Piano Trio No. 1. It's a very special work to me because I first heard it when I was 11 or 12, and even at a young age I was captivated by how one piece of music could have such drama and drive, while maintaining lyrical passages and subtle melodies. This will be my first opportunity to perform Mendelssohn's Piano Trio No. 1 publicly, and I'm happy to share this emotional piece with an audience.
Michail: We are performing a piece that I wrote called Origami Blossom, which I composed specifically for the group that I'm playing with. I am from Greece, so you can hear the influence of Greek music in this composition, along with jazz harmonies, and melodies from my peers' home countries.
Gabriela Fahnenstiel, Classical Piano (MM '19) (left), Michail Tsiftsis, Jazz Guitar (MM '20). Photos by Toby Winarto, Viola (BM '19)
What is your favorite thing about being an MSM student?
Michail: As a jazz musician, New York City is the place to be. I'm a first year master's student here at MSM, and I haven't had a chance to be around musicians of this caliber before, it's amazing. I enjoy working with students who are really focused on their craft and are happy to make music every day.
Gabriela: I could say the same for classical music: everything happens in and around New York! I feel that all great musicians come to NYC at some point in their lives — the atmosphere at MSM, but also in the city, inspires me to keep reaching for my dreams. I've learned a lot from my teachers at MSM, and not just about piano performance, but also the history of my instrument, which is very important to me!
Do you have any other performances or projects in the works?
Michail: I have a few really big gigs in NYC with the group that I'm performing with in this concert, and I'm also looking forward to playing shows in Greece over the summer.
Gabriela: Yes! I have my own small-concert series back home in Germany, called Mary Codman Classics where I organize four to five concerts per season. We also just raised money to get a new Steinway piano in our hall, and it has finally arrived! Now that we have this beautiful instrument available to us, I'm excited to play chamber music with young musicians who are just starting out in their careers, and also with already established artists.
As a jazz musician, New York City is the place to be. I'm a first year master's student here at MSM, and I haven't had a chance to be around musicians of this caliber before, it's amazing.
Michail Tsiftsis
MSM jazz guitarist
MSM Distance Learning Program
https://www.msmnyc.edu/news/msm-spotlight-classical-pianist-gabriela-fahnenstiel-mm-19-and-jazz-guitarist-michail-tsiftsis-mm-20/

redpajama_set_name: RedPajamaCommonCrawl


text:
sports / Karate
PH karatekas bag 19 golds in Karatedo Goju-Kai Asia Pacific Championship
INQUIRER.net / 06:08 PM October 05, 2019
CONTRIBUTED PHOT
MANILA, Philippines—The Philippines hauled in 19 gold medals to finish second overall in the Karatedo Goju-Kai Asia Pacific Championship in Cebu.
The Filipino karatekas secured a total of 82 medals that included 26 silver and 37 bronze medals.
Indonesia was the overall champion with 23 gold, 13 silver, and 21 bronze medals.
Sports drink Milo partnered the Association for the Advancement of Karatedo to organize the event that drew 500 young martial artists across 18 countries from the Asia Pacific region including Japan, Indonesia, Malaysia, and Korea.
Golden State Warriors sign Lee to multiyear contract, bring back Chriss
Coronation night?
Thirdy Ravena gets offers from Asia, Australian ball clubs
"Programs such as the Karatedo Goju-Kai Championships will help expose our Filipino athletes to the international level of competition," said Milo Sports Manager Lester P. Castillo.
"It is truly inspiring to see our young athletes lead the charge in international meets such as this and we hope to see them soon in the global stage."
One-and-done Suerte, UE look to make every game count
Philippine Army to acquire MANPADS, self-propelled howitzers
TAGS: Karatedo Goju-Kai Asia Pacific Championship, Sports
Solon urges Solgen to reconsider quo warranto petition vs ABS-CBN


Okay, maybe not ever night. But most nights. And if he doesn't ask me, I ask him. It's a simple way to end the day on a positive note; to reflect on what good happened, when the natural tendency is to rework and mull over all the things that didn't go so well.
When I first started this gratitude prompt series, it was because of this very question. It's so simple — you'd think a question like that couldn't make any difference at all. But simple does not mean unimportant. Not only is this question an easy way to practice more gratitude, it's also become, in and of itself, one of my favorite parts of the day.
My favorite part of today was… building a fire in our fireplace. A few days ago Mark trimmed back the lilacs, and now we use the sticks as kindling. As we sit and enjoy the crackling flames, I realize how those lilacs bring us so much joy when they bloom… now they are bringing us joy in a new way. I'm grateful to have a house with lilacs, and a fireplace, and to sit and enjoy both with my best friend.


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CDFIs Craft3, Self-Help Complete Second On-Bill Repayment (OBR) Loan Sale
By: David Beck - Dec 03, 2015
Unique Secondary Market Sale Provides Craft3 More Liquidity for Energy-Efficiency Loans
Craft3 and Self-Help today announced that Self-Help Credit Union has purchased an additional $6.4 million On-Bill Repayment (OBR) single-family, energy-efficiency improvement loans. The new deal reflects the strong performance of a $15.7 million OBR portfolio transaction between the two community development financial institutions (CDFIs) in 2013.
"This second sale is more strong evidence that OBR loans perform extremely well while providing homeowners affordable, inclusive, energy-efficiency financing," said Craft3 President John Berdes. "Our hope is to prove OBR loans as a model for expanding access to energy-efficiency and for these secondary market sales to increase liquidity for these loans."
Self-Help has a well-established secondary market home mortgage program and applied its experience to OBR loans. In 2013 the organizations completed the first ever secondary market transaction in the relatively untested OBR market. The purchase proceeds provided Craft3 additional capital to help meet increasing OBR loan demand.
The 2013 OBR portfolio's performance, including a historic total loan loss of less than one percent and high repayment rates, enabled Self-Help to purchase more OBR loans, providing more capital to Craft3 to put even more money to work making loans. It also allowed Self-Help to expand its loan purchase criteria to include all credit scores.
"After all the work on the first purchase balancing Craft3's OBR innovations while creating a viable secondary market transaction for such products, this second deal is all the more gratifying," said Self-Help's Director of Commercial Lending Brian Schneiderman. "The affordability of energy-efficiency improvements like high-efficiency furnaces has been a real barrier for many families. Helping prove OBR programs can expand energy efficiency to families of modest means is a huge leap forward."
Since 2009, Craft3 has partnered with Enhabit (formerly Clean Energy Works) to provide consumer energy-efficiency loans to Oregonians. Craft3's innovative OBR allows homeowners to make loan payments through their monthly utility bill. This expands access to credit for energy-efficiency improvements by eliminating the up-front, out-of-pocket costs that often make upgrades unaffordable. OBR also allows Craft3 to review a homeowner's utility bill payment history as a factor in loan qualification. Using a blend of traditional and non-traditional underwriting techniques, Craft3 has approved loans to over 87 percent of homeowners who apply.
Concurrently, the program helps build a network of contractors with increased green expertise and creates local jobs in this sector. To date, Craft3 and Enhabit's partnership has helped 2,659 Oregon homeowners finance $35.7 million in energy-efficiency upgrades. These homeowners avert more than 6,800 metric tons of greenhouse gasses annually. Overall the program has catalyzed more than $40.9 million of local economic activity, reduced carbon emissions, created jobs for local contractors and reduced home energy use.
With demand for the program increasing, Craft3 needed additional capital for loans, and found a partner in Self-Help. The 2013 sale of Craft3's Home Energy-Efficiency Loan portfolio Self-Help Credit Union represented a new model for attracting capital to energy-efficiency loans supporting upgrades such as installation of high-efficiency furnaces, water heaters and insulation.
A 2014 Lawrence Berkeley National Laboratory (LBNL) policy brief provided an in-depth look at the first portfolio sale. The policy brief examined how the parties addressed challenges in the uncharted territory of valuing OBR loans, selling such a unique portfolio to a federally regulated depository institution, and how the partnership might inform similar investments. The LBNL Policy Brief, as well as extensive details on the loan program and the portfolio sale, can be found at: http://www.craft3.org/Borrow/portfolio-sale.
As a community development lender, Self-Help has long recognized the importance of environmental sustainability in all communities. Cumulatively, Self-Help has made $249 million in direct loans to sustainable businesses, nonprofits, and community facilities. Loans span a range of uses including energy efficient buildings ($137 million), utility-scale solar farms ($76 million), recycling businesses ($15 million) and healthy foods systems ($14.5 million).
Home Energy-Efficiency Loans in Oregon and SW Washington are in collaboration with Enhabit and Energy Trust of Oregon and on-bill repayment through NW Natural, Portland General Electric and Pacific Power. Craft3's efforts to find a secondary market partner were supported by Bank of America, Bullitt Foundation and Laird Norton Foundation. Self-Help also has received support from Bank of America for its energy-efficiency lending.
Jennifer Janda, Craft3 Marketing Manager, 503-791-8228, jjanda@craft3.org
David Beck, Self-Help Media Director, 919-956-4495, david.beck@self-help.org
About Craft3
Craft3 is a nonprofit community development financial institution with a mission to strengthen economic, ecological and family resilience in Pacific Northwest communities. They do this by providing loans to entrepreneurs, nonprofits, individuals and homeowners, including those without access to financing. Craft3 then complement these financial resources with expertise, personal connections and other advocacy for their clients. Learn more at www.Craft3.org.
About Self-Help
Self-Help is a community development lender headquartered in Durham, NC. Founded in 1980, Self-Help has provided over $6.8 billion in financing to 102,000 families, individuals and businesses underserved by traditional financial institutions. It helps drive economic development and strengthen communities by financing hundreds of homebuyers each year, as well as nonprofits, child care centers, community health facilities, public charter schools, and residential and commercial real estate projects. Through its credit union network, Self-Help serves 130,000 families in North Carolina, California and Chicago and offers a full range of financial products and services. Learn more at www.self-help.org.


Stella and I at the museum on our fun Friday's.
Unplug. Get out. Disconnect. Be together and just be.
Dave and Stella heading to the Saturday Fermer's Market.
As I type those words, I feel my breath leave my body and, for a brief moment, I feel the essence of how it feels to just disconnect. Then I'm back, here to explain how this has made a huge impact on my life and how it may also do so for you.
Last night, I was watching "The Sound of Music" with my daughter. She loves music and doesn't get much screen time, so this was a treat. The opening scene comes up as Julie Andrews reaches the top of the hill and is so overcome by the beauty surrounding her that she starts singing, breathes in the life surrounding her and does NOT take an Instagram worthy shot of her on top of the mountain. She didn't get the memo "You're not living unless it's on IG".
How many times in the last month, have you stopped engaging in your surroundings to take a pic to document the "authenticity" of the event for eternity?
Have you ever asked yourself why you chose to stop being present to stand on the outskirts?
Let's face it, there is an addiction that comes with our smartphones that is not healthy. Having a phone in our hand that gives us the unending ability to plug into everyone else's business and unplug from our connection with our own lives is a powerful tool that can have detrimental effects on our lives if we are not intentional about how we use it.
Being intentional about how we use it. That is the key. I'm not suggesting that technology is bad, far from it. What I am suggesting is that we should be intentionally conscious of when and how we choose to use technology. The same goes for how we choose to expose our kids to the same technology.
SCIENCE | What does the research say?
According to Addiction.com, "It's often described as a serious problem involving the inability to control use of various kinds of technology, in particular the Internet, smartphones, tablets and social networking sites like Facebook, Twitter and Instagram." If you can't go an hour without checking your phone, the FOMO you're experiencing may be a bit more serious.
While this disorder is not yet classified by the Diagnostic and Statistical Manual of Mental Disorders (DSM), the reference used to diagnose disorders, there is strong evidence that it is not far off.
In addition, depression, sleep disorders and stress can also occur. Who wants any of that?
A study from the University of Maryland found that when students unplugged from technology, they spent more time with friends and family, exercised more frequently, cooked more and ate healthier foods. Your outlook changes, self-esteem increases and happiness goes up.
Feeling close to people reduces anxiety and depression. For children, it gives them increased confidence and social skills. It will also help regulate emotion and teach empathy.
Being more connected with our loved ones can increase longevity and support our immune system.
Yes, it's harsh, but it is real. This is #theonelife, be intentional with it and spend it well.
If you do not have family time scheduled already, do it now, put it on your calendar.
Invite your kids, make it a big deal, something everyone looks forward to.
Give everyone ownership of what the activity is going be. Ask for input, make a list then do one or two activities at a time ensuring that everyone's activity get's done over time.
Turning off social media notifications during your family time.
Turn on do not disturb setting.
Have fun, engage and just be.
BTW: I recently realized that there is a setting to only allow certain people to call through to your phone when you turn the setting on. This is HUGE for me. If my husband and I are on date night, I can set it so that the nanny, my parents and mother-in-law are the only people who can call me. Those are the important one's in case of emergency; everyone else can wait.
NOTE: Finding pictures for this post was not easy. I take fewer and fewer pics of us on our outings. The quality is not great, but the love is all there.


A 11mi round-trip ride to a historic location from Totton. 37% traffic-free. Ride rating: ★★★. Automatically chosen by our journey-planner: please check you're happy with the route before setting off.
A 35mi round-trip pub ride from Totton. 9% traffic-free. Ride rating: ★. Automatically chosen by our journey-planner: please check you're happy with the route before setting off.
A 32mi round-trip pub ride from Totton. 11% traffic-free. Ride rating: ★. Automatically chosen by our journey-planner: please check you're happy with the route before setting off.
A 44mi round-trip ride to a historic location from Totton. 10% traffic-free. Ride rating: ★. Automatically chosen by our journey-planner: please check you're happy with the route before setting off.
A 37mi round-trip pub ride from Totton. 19% traffic-free. Ride rating: ★. Automatically chosen by our journey-planner: please check you're happy with the route before setting off.
A 30mi round-trip ride to a historic location from Totton. 20% traffic-free. Ride rating: ★. Automatically chosen by our journey-planner: please check you're happy with the route before setting off.
A 35mi round-trip ride to a historic location from Totton. 12% traffic-free. Ride rating: ★. Automatically chosen by our journey-planner: please check you're happy with the route before setting off.
A 52mi round-trip ride to a historic location from Totton. 4% traffic-free. Ride rating: ★. Automatically chosen by our journey-planner: please check you're happy with the route before setting off.
A 51mi round-trip ride to a National Trust location from Totton. 4% traffic-free. Ride rating: ★. Automatically chosen by our journey-planner: please check you're happy with the route before setting off.