text:
\section{I. Introduction}
The statistical mechanics of directed polymers (DPs) has been a very active
field of research for more than twenty years
\cite{Kardar_book,Nelson_book}. The directed paths under study may
represent configurations of ``real'' extended one-dimensional objects
such as polymers \cite{Kamien}  and vortex lines in type-II
superconductors \cite{Blatter}, or may
represent configurations in abstract spaces such as those used to
model sequence alignment in bioinformatics \cite{Hwa}.

Many physical systems consist of aligned extended one-dimensional
building blocks which can have crystalline or fluid-like order in the
transverse plane. Examples include columnar phases of DNA
\cite{Podgornik}, discotic \cite{Chandra} or micellar \cite{Safran}
liquid crystals, ferrofluids \cite{Rosen}, and electrorheological
fluids \cite{Halsey}. In addition, polymer brushes consisting of dense
flexible chains terminally anchored on a surface are characterized by
chain elongation in the direction of the surface normal
\cite{deGennes_brush}. Although the chains of polymer brushes can
assume backtracking conformations, under strong stretching they can be
viewed as directed strings of Pincus blobs \cite{Halperin_Zhulina}. In
recent years, there has been interest in cross-linked polymer brushes
because of promising technological applications \cite{Loveless,Xu}.

The effect of quenched disorder in the embedding medium on arrays of
interacting directed elastic lines has led to the prediction of a
whole zoo of glassy states in high-$T_c$ superconductors
\cite{Blatter}. In real polymer systems, irreversible cross-links can
be viewed as quenched disorder of a different type and their effect
can be studied using the tools of the statistical mechanics of
disordered systems \cite{DE}. A replica field theory has been used to
study the gelation transition due to permanent random cross-links in
systems comprised of Gaussian chains \cite{Castillo},
beads-and-springs \cite{SU_EPL}, dimers-and-springs \cite{Pfahl},
$p$-beine \cite{p-beine}, and wormlike chains \cite{PB_PRL}. A similar
field-theoretic approach to well-cross-linked macromolecular networks
has been developed by Panyukov and Rabin \cite{Pan_Rab1,Pan_Rab2}

In this paper, we employ the same theoretical framework to study the
effect of permanent cross-links on a melt of flexible directed
polymers in a particularly simple geometry. The polymers are stretched
between two parallel flat surfaces with their ends free to slide on
them. We predict a gelation transition upon cross-linking associated
with the emergence of a finite localization length in the transverse
plane which depends on the distance from the boundary surfaces of the
slab.

Furthermore, we investigate mechanical properties of the system. Due
to the asymmetry of the system, one has to distinguish between
\emph{tilt modulus} and \emph{shear modulus}; the first one describes
the resistance to shear of the boundaries in the preferred chain
direction and the latter of the perpendicular boundaries. Remarkably,
the tilt modulus remains completely unaffected upon cross-linking with
cross-links of negligible extent in the aligning direction.

The paper is organized as follows. We present our model in Sec.~II. In Sec.~III, we define and calculate the tilt modulus for the cross-linking geometry of our model. We construct a replica field theory and obtain the gelation transition in Sec.~IV. The shear modulus is discussed in Sec.~V. We summarize in Sec.~VI.

\section{II. Model}
We consider $N$ directed polymers stretched between two planes spaced
a distance $L$ apart. The end points of the polymers are free to slide
on the planes. Each polymer configuration is described by a curve
(path) ${\bf r}(z)=\bigl( x(z),y(z) \bigr)$, where $z \in [0,L]$ and
$z$ is the direction of alignment (Fig.~\ref{schematic}). By the
definition of directedness, these paths exclude loops and
overhangs. The areal density  of the system in the $xy$ plane is $N/A$. We assume free boundary conditions at $z=0$ and $z=L$,
allowing the polymer ends to assume any arbitrary position on the
corresponding planes with any slope. In the absence of cross-links,
the effective free-energy functional (``Hamiltonian'') of the directed
polymers consists of two terms,
\begin{align}
\label{Ham1}
{\cal H}_0 \{{\bf r}_i(z)\}
&=\sum_{i=1}^{N}\frac{\sigma}{2}\int_0^L dz \left(\frac{d{\bf r}_i(z)}{dz}\right)^{\!2} \nonumber\\
&+ \;\sum_{i<j}\frac{\lambda}{2}\int_0^L dz \, \delta\big({\bf r}_i(z)-{\bf r}_j(z)\big), \hspace{15pt}
\end{align}
where the first term penalizes tilting away from the $z$ direction
with $\sigma$ being the effective line tension and the second
term is an excluded volume interaction.

\begin{figure}
\includegraphics[viewport=0 35 527 792,angle=270,width=0.46\textwidth]{dp_schematic3.pdf}
\caption{(Color online) A schematic diagram of directed polymers in a slab of thickness $L$. $z$ is the preferred direction and we refer to $x,y$ as the \emph{transverse} or \emph{in-plane} direction.
\label{schematic}}
\end{figure}

A physical system where the effective free energy of Eq.~(\ref{Ham1})
can be realized is that of strongly stretched wormlike chains of contour length
$L$. If the two plates are held apart by a pressure $P$ and the areal
density (on the $xy$ plane) of the polymers is high, each polymer will
be stretched by a tension ${\cal F}\approx PA/N$. A strong tension allows only
weakly tilting configurations. In this case, the aligning part of the
free energy reads
\begin{align}
\label{Ham_al1}
{\cal H}_{al}^{(1)} \{{\bf r}_i(z)\}
&=\sum_{i=1}^{N}\frac{\cal F}{2}\int_0^L dz  \left(\frac{d{\bf r}_i(z)}{dz}\right)^2 \nonumber\\
&+\;\sum_{i=1}^{N}\frac{\kappa}{2}\int_0^L dz\left(\frac{d^2{\bf r}_i(z)}{dz^2}\right)^2,
\end{align}
where ${\kappa}$ is the bending stiffness of the wormlike chains
related to their persistence length $L_p$ via ${\kappa}=L_p k_{\rm B} T$. For
${\cal F}\gg (k_{\rm B} T)^2/{\kappa}$ and $L\gg L_p$, one can
show \cite{deGennes} that the bending term on the rhs of the previous
equation can be neglected and the projection of the polymer on the
$xy$ plane behaves as a Gaussian chain.

In Ref.~\cite{Halperin_Zhulina}, a realization of a stretched brush is
envisioned as \emph{ABA} triblock lamellae with selective cross-linking of
the \emph{A} blocks. In an analogous realization of our model, the \emph{A} blocks
would form fluid membranes.

Another physical realization of Eq.~(\ref{Ham1}) is that of wormlike
chains interacting with a strong nematic field
\cite{Nelson_book,Kamien}. If the chains are embedded in a nematic
solvent with very large Frank constants and the effective tension due
to the polymer-nematic interaction ${\sigma}$ is such that
${\sigma}\gg (k_{\rm B} T)^2/{\kappa}$, hairpins are negligible. If, in
addition, $L\gg L_p$, the bending stiffness can be neglected altogether
and the chains behave as directed flexible polymers.

In the system described by Eq.~(\ref{Ham1}), we introduce $M$ permanent
cross-links which restrict linked polymer segments
to remain within a distance of order $a$. Their effect is described by
an effective interaction
\begin{align}
  \label{Ham_xlink}
\frac{{\cal H}(\mathcal{C}_M)}{k_{\rm B} T} = \frac{1}{2a^2}\sum_{e=1}^M\big({\bf r}_{i_e}(z_e)
-{\bf r}_{j_e}(z_e)\big)^2.
\end{align}
$\mathcal{C}_M := \{i_e,j_e;z_e\}$ is a quenched configuration of $M$ cross-links identified by the
polymers $i_e,j_e$ involved and the cross-linking height $z_e$. For the sake of simplicity, we assume that the
cross-linking interaction is ``local'' in the $z$ direction and only
depends on the in-plane distance of the polymer segments. As we shall
show in Sec.~III, this assumption has profound consequences for the
elasticity of the cross-linked system.

The partition function of the system for a specific realization of
cross-links, $\mathcal{C}_M$, reads as
\begin{eqnarray}
\label{Z_C_M}
Z(\mathcal{C}_M)=\left\langle\exp\!\left(-\frac{{\cal H}(\mathcal{C}_M)}{k_{\rm B} T}\right)\right\rangle,
\end{eqnarray}
where $\langle...\rangle$ denotes average over all polymer
configurations with Boltzmann weight $\exp(-{\cal H}_0/k_{\rm B} T)$. Physical
observables of interest can be calculated from the quenched-disorder
averaged free energy, $F=-k_{\rm B} T [\ln Z]$, where $[...]$ denotes
average over all realizations of random cross-links. We assume that the
number of cross-links can vary and a realization with $M$
cross-links follows the Deam-Edwards distribution \cite{DE}:
\begin{eqnarray}
\label{DE}
P(\mathcal{C}_M)\propto\frac{1}{M!}\left(\frac{{\mu}^2 A}{2N(2{\pi}a^2)}\right)^{\!M} Z(\mathcal{C}_M).
\end{eqnarray}
The parameter ${\mu}^2 = 2 {[M]}/{N}$ controls the average
number of cross-links per polymer, and the physical meaning of this
distribution is that polymer segments close to each other in the
un-cross-linked phase have a high probability of getting linked.

\section{III. Tilt Modulus}
On large length scales, an array of directed polymers can be described
as an elastic continuum with three elastic moduli: a shear, a bulk,
and a tilt modulus. The first two characterize deformations in the transverse
plane whereas the third characterizes the response to tilting away
from the preferred axis. The elastic free energy of such a system was
proposed in the context of vortex-line arrays in type-II superconductors by
de Gennes and Matricon \cite{deG-Mat}:
\begin{align}
\label{F_el}
F_{el}=\frac{1}{2}\int\frac{d^2 q}{(2{\pi})^2} &\int\frac{d
  q_z}{2{\pi}}\Big\{ (Kq_z^2+Gq^2) \, |{\bf u}({\bf q},q_z)|^2\nonumber\\
&+ Bq_\mu q_\nu u_\mu({\bf q},q_z) u_\nu(-{\bf q},-q_z)\Big\},
\end{align}
where $K$, $G$, and $B$ are, respectively, the tilt, shear, and bulk
modulus. $\mu,\nu$ are Cartesian indices in the $xy$ plane. ${\bf
  u}({\bf q},q_z)$ is the Fourier transform of the two-component
displacement field which parametrizes the elastic distortion of
the vortex-line array.

In order to measure the tilt modulus, we consider a small force, ${\bf f}$,
applied at the upper end point of each polymer and the opposite force,
$-{\bf f}$, applied at the lower end point. The induced deformation is
measured by the average tilt field. The tilt field is defined as
\begin{eqnarray}
\label{tilt_field}
{\bf t}({\bf r},z)=\sum_{i=1}^N\frac{d {\bf r}_i}{dz}\delta\big({\bf r}-{\bf r}_i(z)\big).
\end{eqnarray}
The energy of the system subject to a cross-link configuration $\mathcal{C}_M$
and to a tilting force ${\bf f}$ reads as
\begin{eqnarray}
\label{Ham_f}
{\cal H}_{\bf f}={\cal H}_0+{\cal H}(\mathcal{C}_M)-\int_0^L dz \int d^2r\; {\bf
  f}{\cdot} {\bf t}({\bf r},z).
\end{eqnarray}
To leading order in ${\bf f}$, the average tilt field is
\begin{eqnarray}
\label{resp1}
\frac{1}{LA}\int_0^L dz \int d^2 r \langle {\bf t}({\bf r},z)
\rangle_{\bf f}=\frac{1}{K}{\bf f},
\end{eqnarray}
where $\langle ... \rangle_{\bf f}$ denotes thermal average with a Boltzmann
weight corresponding to the energy functional ${\cal H}_{\bf f}$.
The tilt modulus, $K$, can be extracted from the partition function as
a static linear-response coefficient,
\begin{eqnarray}
\label{tilt_mod}
\frac{1}{K}\delta_{\mu\nu}=\frac{k_{\rm B} T A}{N^2 L} \frac{{\delta}^2}{\delta f_\mu \delta f_\nu}\ln Z_{\bf f}{\bigg\arrowvert}_{{\bf f}={\bf 0}},
\end{eqnarray}
where
\begin{eqnarray}
\label{Z_f}
Z_{\bf f} = \int {\cal D}\{{\bf r}_i(z)\} \exp\!\left(-\frac{{\cal H}_{\bf f}\{{\bf r}_i(z)\}}{k_{\rm B}T}\right).
\end{eqnarray}
In the path integral of the previous equation, we apply a ``Galilean''
transformation (where the height $z$ is viewed as a time-like
parameter) \cite{TN},
\begin{eqnarray}
\label{Galilean}
{\bf r}_i &\longrightarrow& {\bf r}'_i={\bf r}_i\;+\;\frac{{\bf f}}{\sigma}z\nonumber\\
z  &\longrightarrow& z'=z
\end{eqnarray}
which brings it to the form
\begin{eqnarray}
\label{Z_f1}
Z_{\bf f}=Z_{{\bf f}={\bf 0}} \exp\!\left(-\frac{NL}{2k_{\rm B}T \sigma} {\bf f}^2\right),
\end{eqnarray}
where $Z_{{\bf f}={\bf 0}}$ is the partition function without the external field ${\bf f}$. Equations (\ref{Z_f1})
and (\ref{tilt_mod}) yield
\begin{eqnarray}
\label{tilt_mod1}
K=\frac{N}{A}{\sigma}.
\end{eqnarray}
This result implies that the tilt modulus of a directed polymer array
with a specific realization of cross-links of the type described by
Eq.~(\ref{Ham_xlink}) is completely unaffected by
the cross-links and simply reduces to the single-polymer tension. Since
any realization of the quenched disorder associated with the
cross-links of this type would give the same result, we are spared the burden of
having to use replicas for the calculation of the average over disorder.

The reason behind the particularly simple result for the tilt
modulus is the ``Galilean'' invariance of the interactions between
the polymers as well as of the boundary conditions. In the specific
model, both the excluded volume interaction and the cross-link
interaction involve polymer segments at the same height $z$ and
therefore remain unchanged under a ``Galilean''
transformation. Real cross-linking molecules have a finite extent and
may link to polymer segments at different heights thus breaking the
``Galilean'' invariance. That would lead to a non-trivial renormalization of the
tilt modulus. In the limiting case of cross-links with negligible extent, our
model is a good approximation, and we expect the tilt modulus to remain
unchanged  and be given by
Eq.~(\ref{tilt_mod1}).

\section{IV. Gelation Transition}
The system of cross-linked directed polymers undergoes a gelation
transition as the number of cross-links per chain increases. Whereas in
the sol phase the DPs are free to move in the $xy$ plane like particles
in a two-dimensional fluid, the polymers' motion in the gel phase is restricted to
finite excursions around preferred positions. Thus there is a
localization transition in the $xy$ plane, similar to the gelation
transition in systems comprised of other building blocks in $d=3$ \cite{Castillo}. Since
the latter has been discussed extensively, we keep our discussion
short.

What is the \emph{order parameter} for the localization transition in the $xy$
plane? A point $z$ on  curve $i$, i.e., monomer $z$ on polymer $i$ in
a discretized model, is localized, if it has a nontrivial expectation
value
\begin{equation}
\label{local_density}
\langle\delta({\bf x}-{\bf r}_i(z))\rangle\neq 1/V.
\end{equation}
If the particles are localized at random positions, as we expect for
the gel phase, then the density averaged over all particles
vanishes at any nonzero wave vector. A possible order parameter is the second moment of the local
density:
\begin{equation}
\Omega^{(2)}({\bf q},z)=\frac{1}{N}\sum_{i=1}^N
\bigr[\langle e^{i{\bf q}\cdot{\bf r}_i(z)}
\rangle \langle e^{-i{\bf q}\cdot{\bf r}_i(z)} \rangle\bigr]\;.
\end{equation}
In general, one polymer is cross-linked with a finite number of other
polymers and in fact close to the transition this number is
small. Hence there is no reason to expect that the local density
should obey Gaussian statistics, therefore we need all moments of the
local density to characterize the gel. This is achieved in the replica
formalism by introducing $n$ copies, one for each thermal
expectation value. The order parameter in the replica theory
\begin{equation}
\label{order_parameter}
  \Omega({\bf x}_1...{\bf x}_n,z)=\frac{1}{N}\sum_{i=1}^N
\bigl[\langle \delta({\bf x}_1-{\bf r}_i(z))\rangle \cdots
\langle \delta({\bf x}_n-{\bf r}_i(z))\rangle\bigr], \nonumber
\end{equation}
captures all moments of the local density and hence characterizes the
structure completely.

The average over the quenched realizations of cross-links, $\mathcal{C}_M$, is done with
help of the replica trick.
The disorder averaged free energy $F=-k_{\rm B} T [\ln Z]=\lim_{n\to 0}
({\cal{Z}}_{n+1}-{\cal{Z}}_1)/(n{\cal{Z}}_1)$ is represented in terms of
$n$ noninteracting copies of the system together with one additional
replica to account for the distribution $P(\mathcal{C}_M)$ of
Eq.~(\ref{DE}) which is proportional to the partition function.
The replicated partition function is represented as a functional
integral over collective fields $\Omega(\hat{q},z)$,
\begin{subequations}\label{eq:ZnpeAll}
\begin{align}
{\cal{Z}}_{n+1} =& \int\mathcal{D} \Omega \, e^{-{N\!f_{n+1}}}\;, \label{eq:Znpe}\\
\label{free_energy}
  f_{n+1}(\Omega)  =&\;  \phi^n \frac{\mu^2}{2L} \int_0^L \!
  dz \!\sum_{\hat{q} \in {\rm HRS}} |\Omega(\hat{q},z)|^2 \Delta(\hat{q})\nonumber\\
  &+ \frac{1}{2L} \int_0^L \!
  dz \!\sum_{\hat{q} \in {\rm 1RS}}
  |\Omega(\hat{q},z)|^2 \tilde{\lambda}(\hat{q})\nonumber\\
&- \ln \mathfrak{z} \;,
\end{align}
\end{subequations}
with the single-polymer partition function
\begin{align}
  \mathfrak{z} = & \int  \mathcal{D} \hat{r}(z) \, e^{-H_{0}^{(n+1)}} \label{eq:free_energy_z}\\
  &\times\exp\Biggl(\frac{ \phi^n\mu^2}{L} \int_0^L dz  \sum_{\hat{q}
    \in {\rm HRS}} \Delta(\hat{q})  \Omega(\hat{q},z) e^{-i\hat{q} \cdot \hat{r}(z)}\nonumber\\
   &\hspace{34pt}+ \frac{i}{L} \int_0^L \!
  dz \!\sum_{\hat{q} \in {\rm 1RS}} \tilde{\lambda}(\hat{q}) \Omega(\hat{q} ,z) e^{-i\hat{q} \cdot \hat{r}(z)} \Biggr) \;, \nonumber
\end{align}
where
\begin{align}
 \tilde{\lambda}(\hat{q}):= \lambda \frac{L N}{2A} - \phi^n {{\mu}^2\Delta(\hat{q})}\;.
\end{align}
To simplify the notation we have introduced hatted vectors, such as
$\hat{q}:=({\bf q}_0,{\bf q}_1,...{\bf q}_n)$ for $(n+1)$-fold replicated
vectors. We have also adopted units of energy such that $k_\text{B}T\equiv
1$. The harmonic potential
for the cross-links is reflected in
$\Delta(\hat{q})=\exp{(-a^2\hat{q}^2/2)}$ and $\phi=2\pi a^2/A$. The collective field
$\Omega$ is almost the order parameter, discussed above, except for
the zeroth replica which we have introduced to account for the
disorder average $[...]$ in Eq.~(\ref{order_parameter}).

Areal density fluctuations are  represented by $\Omega(\hat{q},z)$ with
$\hat{q}=({\bf 0},...{\bf q}_{\alpha},...{\bf 0})$, i.e., only one
nonzero component (1RS). These fluctuations are penalized by the excluded
volume interation. The stability of the liquid state in mean-field
approximation (uniform density) is controlled by the coefficient of
the quadratic term in the fluctuations. A sufficiently strong excluded
volume interaction such that $ \tilde{\lambda}(\hat{q}) \gg 1$
together with the positive definiteness of the kernel (in $z_1,z_2$)
$\langle e^{-i\hat{q} \cdot (\hat{r}(z_1)- \hat{r}(z_2))}
\rangle=\exp(-\hat{q}^2|z_1-z_2|/2\sigma)$ preclude a collapse of the
liquid state. Since the areal density fluctuations are noncritical, we only
consider the order parameter in the so-called higher replica sector
(HRS) consisting of vectors $\hat{q}$ with at least two nonzero
components.

The expectation value of the order-parameter field
\begin{equation}
\left\langle\Omega(\hat{x},z)\right\rangle_{f}=
\left\langle \delta (\hat{x}- \hat{r}(z)) \right\rangle_{f}
\end{equation}
has to be calculated self-consistently with the weight of
Eq.~(\ref{eq:ZnpeAll}). Here we restrict ourselves to the saddle-point
approximation $\delta f_{n+1}/\delta \Omega=0$.
As for the gel transition of random coils, the saddle-point equation
is solved exactly by the following ansatz for the order parameter:
\begin{align}
\label{eq:dp:ansatzQ}
\Omega(\hat{q},z) =&\; (1-Q) \delta_{\hat{q},\hat{0}} \nonumber\\
&+ Q
\delta_{{\bf q}_{\parallel},{\bf 0}}
\int_0^\infty \!\! d \xi^2  \mathcal{P}(\xi^2,z)
\exp\!\left( - \frac{\hat{q}^2 \xi^2}{2}  \right).
\end{align}
Here $Q$ denotes the fraction of DPs in the infinite cluster and hence
$1-Q$ is the fraction of DPs in the fluid state, giving rise to the first
(trivial) contribution to the order parameter. On the other hand, the
localized particles are characterized by the localization length
$\xi$, which fluctuates not only from polymer to polymer but also
along one directed polymer giving rise to a distribution of localization length
\begin{equation}
\mathcal{P}(\xi^2,z)=\frac{1}{QN}\sum_{j\in Q}\bigl\langle\delta\bigl(\xi^2-\xi^2_j(z) \bigr) \bigr\rangle
\end{equation}
which depends on $z$. After averaging over the disorder the system
still has macroscopic translational invariance in the $xy$ plane. This
requires that ${\bf q}_{\parallel} := \sum_{\alpha=0} ^n{\bf q}_{\alpha} = 0$.

The solution of the saddle-point equation reveals a gel transition at a
critical cross-link concentration
$\mu^2=1$, when a macroscopic cluster of cross-linked DPs is formed.
The gel transition is signaled by a nonzero value of the gel fraction
$Q$. Close to the gel transition, $\epsilon=\mu^2-1\ll 1$ grows
continuously from zero:
$Q=2\epsilon+{\cal O}(\epsilon^2)$.
To discuss the distribution of localization length, we note that we
have several length scales in our system: the internal length of a
directed polymer, $L$, the length of a cross-link, $a$, and the radius
of gyration in the $xy$ plane, which is determined by
$l:=\sqrt{L/(2\sigma)}$. We expect that the latter will set the
scale for the localization length, introduce the abbreviation
$\theta=(2/3+a^2/l^2) l^2/(\xi^2 \epsilon)$
and consider the distribution of rescaled, inverse localization
length, $\pi(\theta,s=z/L)$, with
\begin{equation}
\pi(\theta,s)d\theta=\mathcal{P}(\xi^2,Ls)d \xi^2.
\end{equation}
This function is the solution of
\begin{align}
&( 1 +  2\epsilon) \pi(\theta,s)
 =  ( 1 +  \epsilon ) \int_0^1 \! d s_1 \,  \pi(\theta,s_1)  \\
&\hspace{5pt} + \frac{\epsilon}{2/3+a^2/l^2} \int_0^1 \! d s_1 \, \partial_\theta
\Bigl( \theta^{2}\pi(\theta,s_1) \Bigr)
 \bigl\{  2 |s - s_1| +  a^2/l^2   \bigr\} \nonumber \\
&\hspace{5pt} +  \epsilon  \int_0^1 \! d s_1 d s_2 \int_0^\theta  d\theta_1 \,
\pi(\theta_1,s_1) \pi(\theta - \theta_1,s_2)
+ {\cal O}(\epsilon^2)  \;. \nonumber
\end{align}

To gain a better understanding of the solution, we decompose the
distribution into its mean with respect to $s$, $\bar\pi(\theta)= \int
ds \,\pi(\theta,s)$ and a deviation: $\pi(\theta,s)=\bar\pi(\theta)+
\delta\pi(\theta,s) $. The mean, $\bar\pi(\theta)$, fulfills the same
equation as for isotropic gels \cite{Castillo}. The deviation is
small close to the gel point,
\begin{eqnarray}\label{eq:dp:DistEquationdp3}
\delta\pi(\theta,s)
& = &\epsilon w(s) \, \partial_\theta \Bigl( \theta^{2} \bar\pi(\theta) \Bigr)
  + {\cal O}(\epsilon^2)  \;, \\
 w(s)& =& \frac{ s^2 + (1-s)^2 - 2/3}{\qquad  a^2/l^2 + 2/3}  \;,
\end{eqnarray}
and furthermore controlled by the ratio of cross-link length to
in-plane radius of gyration: $a_l^2 := a^2/l^2$. The larger
the radius of gyration $l$, the more pronounced is the dependence on $s$.
We show the distribution for a
typical value $a_l^2=0.1$ in Fig.~\ref{color_distrib}. As one would
expect, localization is strongest in the middle of the directed polymer
and weaker at the boundaries. The variation across the length of the
DPs is stronger for larger localization length (small $\theta$).

To get a better understanding of this anisotropy, we show in
Fig.~\ref{fig:distrib(s)} cuts of Fig.~\ref{color_distrib} for two
fixed $\theta$ values. As one can see, large localization lengths
(such as $\theta = 1/2$, solid red curve) are favored at the boundaries
($s\approx 0,1$), and small localization lengths (such as $\theta = 2$,
dashed blue curve) in the middle of the sample ($s \approx 1/2$). This
behavior is reasonable, since the ends of the chains are more loose. A chain segment close to the top (bottom) boundary has a lower
probability to have a cross-link above (below) and hence is on average
less localized than a chain segment in the middle.

\begin{figure}
\begin{minipage}[h]{.33\textwidth}
\includegraphics[width=.99\textwidth]{deltaP.pdf}
\end{minipage}
\begin{minipage}[h]{.05\textwidth}
\includegraphics[height=5cm]{deltaPColorBar_a0.pdf} \\[5pt] \
\end{minipage}
\begin{minipage}[h]{.05\textwidth}
\includegraphics[height=5cm]{deltaPColorBar_a01.pdf} \\[5pt] \
\end{minipage}
\caption{(Color online) Height-dependent part, $\delta \pi(\theta,s)$, of the
  distribution of inverse localization length, $\theta$, as a function of $\theta
$ and $s:=z/L$. Due to the scaling behavior close to the sol-gel
transition, $\delta\pi(\theta,s)$ is normalized with $\epsilon$. $a_l^2$
is the ratio squared of the in-plane extent of a cross-link to the in-plane
radius of gyration of a free DP.}
\label{color_distrib}
\end{figure}
\begin{figure}
\includegraphics[width=.33\textwidth]{deltaPtheta05and2.pdf}
\caption{(Color online) Height-dependent part, $\delta \pi(\theta,s)$, of   the
  distribution of inverse localization length, $\theta$
  \emph{vs.}~the normalized system height $s=z/L$, for $\theta=1/2$
  (solid, red) and $\theta=2$ (dashed, blue). The cross-link extent is
  $a^2=0$ for both graphs. As in Fig.~\ref{color_distrib}, $\delta\pi(\theta,s)$ is scaled with $\epsilon$.}
\label{fig:distrib(s)}
\end{figure}

\section{V. Shear Modulus}

In the gel phase, the DPs are localized in the $xy$ plane. Hence the
symmetry with respect to translations in the $x$ and $y$ directions is
spontaneously broken as indicated by a nontrivial expectation value of
the local density as defined in Eq.~(\ref{local_density}). The symmetry breaking occurs
on a local level only, while the macroscopic system (averaged over the
cross-link related disorder) remains homogeneous. We expect low-energy Goldstone
fluctuations and a finite stiffness to static shear deformations in
the $xy$ plane (see Fig.~\ref{schematic}).
In the replica formalism, the overall macroscopic translational
invariance is reflected in common translations of all $n+1$ replicas,
whereas replica-dependent translations generate a family of order
parameters which all give rise to the same free energy

To investigate the response of the system to shear deformations, we
start from the replica free energy [Eq.~(\ref{free_energy})] and
consider fluctuations around the saddle point (\ref{eq:dp:ansatzQ}),
which correspond to long-wavelength shear deformations ${\bf
  u}^{\alpha}({\bf r})$ in each replica $\alpha=1,..., n$ except the
zeroth replica \cite{SU_EPL,GoldstoneFluct,GoldstoneFluctEPL}. The
latter represents the preparation state before the cross-linking
process, which takes place in a state without shear deformations. We
furthermore want to consider pure shear only and hence require that
volume is conserved, $\nabla\cdot {\bf u}^{\alpha}=0$, and no tilt deformations
are excited; i.e., ${\bf u}^{\alpha}({\bf r})$ are chosen to be
independent of $z$.

The order parameter for the deformed state thus reads as
\begin{align}
\Omega_u(\hat{q},z) &= (1-Q) \delta_{\hat{q},\hat{0}} +  \nonumber \\
&Q \int\!\! \frac{d^2 r}{
} \exp\bigl(i {\bf q}_\parallel \cdot {\bf r} + i\sum_{\alpha=1}^n
{\bf q}_\perp^{\alpha}\cdot
{\bf u}^{\alpha}({\bf r}) \bigr) \nonumber \\
&\times \int_0^\infty \!\! d \xi^2  \mathcal{P}(\xi^2,z)
\exp\!\left( - \frac{\hat{q}^2 \xi^2}{2}  \right)
\label{eq:dp:ansatzQ(u)}\;,
\end{align}
where ${\bf q}_\perp^{(\alpha)} := {\bf
  q}^{(\alpha)} - \frac{1}{n+1} {\bf q}_\parallel $.
If the deformations are taken to be spatially uniform we recover the general
solution of the saddle-point equation. Fluctuations around the saddle-point value are incorporated by nonzero $\partial_{x} {\bf u}$ and $\partial_{y} {\bf u}$. These are assumed to be small, corresponding to long-wavelength excitations.

We plug the ansatz (\ref{eq:dp:ansatzQ(u)}) into the free energy
(\ref{free_energy}) and only keep the lowest order in $Q$ and in the
derivatives $\partial_{x} {\bf u}$ and $\partial_{y} {\bf u}$.  Higher
order derivatives, such as $\partial^2_{x,y} {\bf u}$, are
neglected. The result has the form of an elastic free energy of an
incompressible medium,
\begin{align}
  f_{n+1}(\Omega_u) &= f_{\rm sp} + \frac{G}{2N} \int d^2 r
  \sum_{\mu,\nu=1}^{2} \sum_{\alpha=1}^n \left(\frac{\partial u_{\nu}^{\alpha}}{\partial r_\mu} \right)^{\!2} \;.
\end{align}
There $f_{\rm sp}$ is the saddle-point value of the free
energy and $G$ is the shear modulus,
\begin{align}
  G = \left(\frac{Q^2 (\mu^2-1)}{2} - \frac{Q^3}{6} \right)
  \frac{N}{A} k_{\rm B} T \;.
\end{align}
With the distance from the sol-gel transition $\epsilon = \mu^2 - 1$,
the relation $Q=2\epsilon + {\cal O}(\epsilon^2)$ found in the
previous section, and the areal density $n_0 := N/A$ of the polymer
chains, the shear modulus simplifies to
\begin{align}
 G = \frac{2}{3} \epsilon^3 \, n_0 \, k_{\rm B} T \;.
\end{align}
The scaling of the shear modulus $G \propto \epsilon^3$ close to the
sol-gel transition is in agreement with previous results for isotropic systems
\cite{SU_EPL,GoldstoneFluct,GoldstoneFluctEPL}. This result for the
shear modulus is universal and does not depend on the microscopic
length or energy scales which characterize the polymers and the cross-links.

\section{VI. Conclusions and Outlook}

We have addressed the effect of random permanent cross-links on an array of
directed polymers confined between two planes with their end points free
to slide on them. The cross-links are assumed to have negligible
extent in the preferred direction of the DPs (local in the $z$
direction), but they are spring-like in the transverse ($xy$)
plane. The constraints imposed by the cross-links are treated as
quenched disorder which follows the Deam-Edwards distribution.

At a certain critical cross-link density, there is a
continuous gelation transition from a sol phase where the DPs are free to
wander in the $x$ and $y$ directions to a gel characterized by the emergence of
finite localization lengths for the polymer segments which belong to
the infinite percolating cluster. Unlike other isotropic polymer systems which undergo
a similar transition, the DPs are inherently anisotropic and this is
reflected in the height ($z$) dependence of the order parameter and
the associated distribution of localization length. Because of the
finite extent of the system in the preferred direction, larger localization lengths are favored
closer to the boundaries where the polymer end points are free to slide.

The gelation transition is accompanied by the emergence of a finite
shear modulus. Our result for the array of cross-linked DPs close to
the gel point agrees with previous results for isotropic systems thus
suggesting universality. As far as in-plane localization and the
relevant shear modulus are concerned,
our system can be viewed as effectively two dimensional. It
is well known that truly long-ranged positional order cannot exist in
two dimensions \cite{Nelson_book}. In \cite{GoldstoneFluct}, it was shown for isotropic
systems that fluctuations drive the order parameter to zero as
expected from the Mermin-Wagner theorem. Yet a quasi-amorphous solid
state survives. It is characterized by a finite stiffness to static
shear deformations and algebraically decaying correlations.

The asymmetry of our system due to the preferred direction of the DPs
entails the existence of a tilt modulus which is different and
independent from the shear modulus. We have only considered
the simplest case of cross-links with negligible extent
in the preferred direction of the DPs.  Using a ``Galilean''
invariance argument, we have shown that cross-links of this type leave the tilt modulus of the
uncross-linked system completely unaffected. We expect
cross-links which connect polymer segments at different heights to
induce an effective ``nonlocal in $z$'' interaction between the
connected polymers. By analogy to a similar interaction in the case of
flux lines in type-II superconductors \cite{tilt}, we can expect the
breaking of the ``Galilean'' invariance to cause an upward renormalization (stiffening) of
the tilt modulus. This putative renormalization may be useful to
quantify the cross-link induced collapse of polymer brushes. We hope to
report on these issues in a future publication.

\section{Acknowledgements}
We gratefully acknowledge financial support by the DFG through Grant No.\ SFB\,602.
P.B.~acknowledges support during the later part of this work by
EPSRC-GB via the University of Cambridge TCM Programme Grant.

redpajama_set_name: RedPajamaArXiv


text:
Career moves Bond counsel
Former Chicago council member joins Clark Hill
By Yvette Shields April 27, 2018, 3:42 p.m. EDT 1 Min Read
CHICAGO – Attorney and former Chicago City Council member Latasha Thomas has joined the ranks of Clark Hill Plc's government and public affairs group.
Thomas recently joined the firm as senior counsel. Her practice will include public finance work.
"Latasha is widely respected by governmental leaders at all levels throughout Chicago, Cook County and the state of Illinois," the firm's managing member of the Chicago office, Ray J. Koenig III, said in a statement.
Thomas will work on "solving clients' issues with regard to federal, state and local governments; municipal finance; economic and urban development; real estate; mergers and acquisitions; and business transactions, including private equity investing," the firm said.
Thomas was appointed alderman of the city's 17th ward in 2000 and went on to win four year terms in 2001, 2005, and 2011. She did not seek re-election in 2015 and most recently had served in an of counsel role at Reyes Kurson.
During her tenure on the council, Thomas served as chair of the Education Committee and she promoted the use of the city's fiscal muscle to bolster the hiring and advancement of minorities and women at non-minority firms. An ordinance sponsored by Thomas required any law firm, financial advisor, or underwriter that provides professional services to the city on a bond offering disclose the gender, role and race or ethnicity of the firm's team on the deal regardless of the firm's ownership status.
Career moves Bond counsel Illinois

redpajama_set_name: RedPajamaCommonCrawl


text:
Q: Thumb or finger detection android I am working on heartbeat application. When you place your thumb or finger on top of camera it calculate user heartbeat So right now if you place anything on camera it starts to calculate it's heartbeat.
Now i want to put some detection on that so that it only calculate heartbeat when user place finger on it.
So how i can i achieve that? any guidance or help?

A: I don't think you will be able to detect the finger for 100% of the times .
But when a user puts hes finger on the camera you can check if the color is red'ish but then any thing red will be a positive detection (false positive).

redpajama_set_name: RedPajamaStackExchange


Extra strong bags for heavy-duty applications. • Meets FDA and USDA specifications for food contact and applications.
• Bags can be twist-tied, heat-sealed or taped. Heat sealers, twist ties, bag tapers and bag tapes are also available.
• Bags 15" wide and under are packed in inner dispenser packs of 100 bags each for cleanliness and convenience.
• 6 Mil - Extra heavy-duty. Puncture resistant.
• Made from seamless tubing with no slits or side seals that can rip.
• 100% virgin, high clarity polyethylene film.
• 4 Mil - Heavy-duty protection for hardware, industrial parts and tools.


I don't have any Nikon optics. I know friends that do, and like them fine.
I was never a fan of the circles inside the BDC reticles in the Nikons, but that is all that holds me back from trying some of their mid range to high end scopes. For BDC reticles, I want cross hairs and lines. Not circles. Just my opinion.
Some other options you could look into in a similar price range.
Vortex Optics, Viper series of scopes. They have BDC reticles available, made well, and have a lifetime transferable warranty. I have 6 optic pieces from vortex including binos, scopes and a spotter. I have used the warranty one time when a scope got squirrely. I mailed it on a Tuesday from IL to WI….and had it back the following Monday, like new. I hated that the scope developed an issue, but the customer service was excellent.
Leupold makes nice optics in the VX-2 line that are similar in price. Again, BDC reticles available, made well (not as good as years ago), and have a lifetime transferable warranty. I have a couple Leupolds, and one needs warranty work now, but I haven't sent it in yet.
Shop Camera Land New York online. I find them hard to beat on price and service, and they have demo models available often at even greater discounts.


text:
Groupon enters a crowded market for deals in China
Benjamin Haas on 2011-05-06
Reporting from Beijing— Groupon Inc. may be the undisputed king of Internet coupons in the United States.
But with its March launch in China, the Chicago company has stepped into a cutthroat market saturated with thousands of competitors — including a copycat that's already using its English name.
Rechristened in China as Gaopeng.com, which evokes a famous saying to gather honored guests, Groupon is hoping to seize a foothold in a country that's increasingly turning to the Web to buy and sell goods and services.
E-commerce in China grew 100% last year to $70 billion. Led by Internet giant Taobao, a sort of Chinese answer to EBay Inc. and Amazon.com Inc., the industry is expected to grow another 60% to 80% this year, according to China Market Research Group.
Daily deal sites such as Groupon are relative newcomers, raking in $300 million of the e-commerce pie in 2010. But China's emerging consumers are expected to boost the sector tenfold this year to $3 billion, according to Tuan800, a website that tracks the industry in China.
"It's really taken off like it has in the U.S.," said Bill Bishop, a Beijing-based investor and independent Internet analyst. "Consumers love it. Who doesn't love a deal?"
Also known as group buying sites, operations such as Groupon generally work like this: The companies partner with local businesses to offer products and services at deep discounts, marketing the deals through emails sent to subscribers daily. Some sites require a minimum number of buyers to respond before they'll make good on the offer. Buyers typically have 24 hours to purchase the deals, which can be downloaded and printed as coupons that merchants will honor for weeks or months.
China's 450 million Internet users can find bargains on a wide variety of offerings including massages, hotpot dinners, Japanese condoms, doctor visits, infant formula and bridal photos. In September, 200 Mercedes-Benz Smart cars discounted by 33% to about $20,000 sold out in three and a half hours.
Zhao Yajie is one of the millions of Chinese consumers who have bought into the trend. She obsessively scours group buying websites for the latest deals, focusing on neighborhood restaurants and Japanese lingerie. When she finds a particularly good bargain, she emails it around or sends it to people over QQ, China's most popular instant messaging service.
"And sometimes my friends send me deals too," said the 28-year-old investment manager. "Recently, a friend bought me a coupon to a lobster restaurant."
Zhao even sends deals to her boss. In a country where haggling for almost everything is the norm, this isn't considered unprofessional or embarrassing.
"If you take away the technology behind group buying, this isn't new," said Kevin Lee, chief operating officer of China Youthology, a research and consulting firm that focuses on Chinese youth trends. "The motivation has always been there, trying to get the best deal, talking down the price, using coupons."
Officials from Groupon's China operation declined to comment on its recent launch. Analysts said the company must find a way to wade past rival sites to get on the radar of people such as Zhao — and then somehow inspire brand loyalty.
"The consumer [in China] doesn't really care who is who," said Edward Yu, chief executive of Beijing-based Analysys International. "As long as the browsing experience is good, the price is good, they don't care who is providing the service."
To tackle the Chinese market, Groupon has partnered with Tencent Holdings Ltd., China's second-largest Internet company and operator of the popular QQ messaging service. Yunfeng Capital, an investment fund started by Jack Ma, founder of Alibaba Group, which includes Taobao, is a minority owner of the new platform.
Experts point to Groupon's ability to leverage Tencent's large user base as its only chance for survival in the saturated market. Others predict Groupon will simply acquire smaller firms, a tactic it has used before when entering overseas markets. One-third of the company's revenue comes from outside the U.S.
Groupon has plenty of catching up to do in China. The company offers deals in 11 Chinese cities, while rival Lashou.com, one of the largest Chinese sites, operates in more than 500 cities. Lashou.com and Meituan.com, another big player, each launched massive advertising campaigns ahead of Groupon's Chinese debut.
That's not the only challenge. A few knockoffs have already emerged, including Groupon.cn, started by an information technology services company that abandoned that business to pursue the group buying craze.
In December, the Ministry of Commerce singled out the industry for being too chaotic and in need of tighter regulation. Recently, for example, a daily deals website based in Zhejiang province in eastern China allegedly defrauded more than 500 people by offering deeply discounted movie tickets that a local theater never agreed to honor, according to a report in the Qianjiang Evening News.
But some Chinese said the deals are so good that they're worth the risk.
Zou Shuang, 24, scored big on a large karaoke room and brought 14 family members along for hours of entertainment. The cost: about $3.
"My parents were pretty impressed," she said.
But the deals may not last. Like their U.S. counterparts, some Chinese business owners complain that bargain hunters rarely become repeat customers.
"When we don't offer a discount the number of people drops by 80%," said Ji Hongmei, a marketing manager at Stellar International Cineplex in Beijing.
Consumers such as Zhao, the investment manager, readily admit to such behavior.
"I wouldn't go back to 80% of the restaurants I've been to because of group buying discounts," she said. "Most of them are just so mediocre."
By Benjamin Haas of Los Angeles Times
Previous article Taiwan's commonsense consensus
Next article How to See the Real China: Ride Beijing's Subway
EMPIRE Has Fallen, Though Washington May NOT Know It Yet


Monument had been source of speculation in diplomatic circles.
The monument at the corner of Island Park Drive and the Sir John A. Macdonald Parkway, photographed in August.
The Canadian and Turkish foreign ministers are expected to unveil an Ottawa monument on Thursday built to honour fallen diplomats, including a Turkish envoy killed in Ottawa 30 years ago, Embassy has learned.


text:
Vaccination: A bioethical Islamic perspective
Posted by Hyder Gulam | 24 Mar, 2018 | Education, Other News, Uncategorized | 0 |
The preservation of life as a principle of Islam and our faith gives greater honour to human life.
Our great Muslim scholars like Ibn Sina have stated that "Medicine is the preservation of health and restoring it when it gets lost", to accept a lesser harm, in order the ward off a greater one, or to forego a certain benefit to obtain a greater one.
Vaccination is a medical preparation intended to produce an immunity to a disease by stimulating the production antibodies in the host body. Vaccines include suspensions of killed or attenuated microorganisms, products or derivatives thereof.
The most common method of administering vaccines is by injection, oral and nasal spray.
Many diseases have been prevented and even eradicated by the implementation and monitoring of a vaccination program, such as polio, measles etc.
The higher objectives of Shariah as expounded by scholars of Islam are the preservation of religion, human life, progeny, material wealth and human reason. Islamic law aims to preserve essential and other interests by preserving their existence and also protecting them from destruction.
One of the cardinal principles of Islamic law is to achieve benefits and ward off harm and corruption. We should also remember and practice the Prophetic traditions, where our beloved Prophet (s) not only sought remedy for himself, his family and companions, but also he used and advised certain medicaments eg black cumin (black seed, nigella sativa), aloe vera, senna, henna (lawsonia inermis), hijama (cupping) and using honey for many ailments, and their prevention (such as eating 7 arjwa dates every morning).
The views and opinions on the contemporary process of vaccination are quite nuanced and evidence that supports the process exists in abundance.
For instance, the eminent Muslim scholar Sheikh Yusuf Al-Qaradawi states that using vaccines to boost immunity against disease is lawful, for it is a means of warding off something evil before it afflicts people.
It is a duty of Muslims to do their best to ward off harm of all kinds, either before or after it comes. There is a juristic rule in this regard: Harm is to be warded off as much as possible.
In fact, evidence and proofs state that the polio vaccine contains neither harmful elements nor impure ones and that it does not cause infertility as stated by opponents of vaccination.
This is the first argument that supports the vaccination drives and refutes the arguments of those who have claimed that the vaccine is harmful and thus unlawful.
Second, parents are responsible for providing their children as much as they can with all means of protection and immunity against harm and diseases in order to save them long-life suffering.
Third, people in authority in every country are to enact laws and take actions, by means of which the health of people in general, and children in particular, is to be protected against diseases. In this regard, the government imposes a mandatory immunization scheme for children the requirements of which become more severe in cases of certain epidemics, such as meningitis.
An example of this is when Muslims pilgrims to Makkah and Madinah must have vaccination certificate as a right of entry.
Fourth, things are primarily in a state of purity. Experts in the field in question, ie, the vaccinations and immunizations, are the World Health Organization (WHO). The WHO has stated that the vaccines is not harmful in any way, nor does it include impure elements or cause infertility (i.e. polio vaccines).
Fifth, vaccine has been used for a long time all over the world, including more than fifty Muslim countries, and has proved to be highly effective in eradicating diseases.
No outstanding scholar, whether from Al-Azhar University, or anywhere else, has been reported to have objected to the use of such vaccine.
The Saudi scholar, Sheikh ibn Baaz also has provided a very useful ruling on giving treatment before sickness occurs, such as vaccinations. He said that there is nothing wrong with giving treatment if there is the fear that the disease may occur because of the presence of an epidemic or other factors which may cause disease.
This is a method of warding off a problem before it happens. So if there is the fear of sickness and a person is vaccinated against an infection that is present in the land or elsewhere, there is nothing wrong with that, because it is a kind of protection.
The Mufti of Kelantan (Malaysia), Mohamad Shukri Mohamad has said that Islam allows the use of vaccine although it contains 'haram' substances (forbidden in Islam) when there is no other medicine available.
The respected Mufti has said that Islam stressed on the well-being of its followers in terms of faith, life, mind, lineage and wealth, as such the vaccine is permissible in Islam. Following this line of logic, the August European Council of Fatwa and Research (1-7 July 2003) has clearly stated that it is permissible to use vaccinations for the treatment and prevention of harm, especially since forbidding its administration will result in greater harm for the individual, family and community. According to them, this holds even if it is known that the vaccine may be from impure sources (such as the enzyme trypsin).[1]
As social media becomes a prominent source of information, our media experts have cautioned against uncritically accepting information from non-reputable sources.
Dr Nasya Bahfen a former ABC and SBS reporter, course coordinator – Masters in Journalism program at La Trobe University, has said that it's so important to defer to the sources who attribute recognised scientific publications and mainstream medical professionals.
"Reputable media outlets won't give the time of day to the anti-vaccination lobby, and won't fall into the trap of a false equivalency as if the anti-vaccination movement – which is actually tiny – is on the same level as the majority of scientific finding. There is no such thing as a media conspiracy with this – there is no huge secret the anti-vaccination movement knows that the medical profession and medical researchers don't know."
As Muslims, whose civilisation contributed greatly to the development of the scientific method, we should be wary of seeking medical advice from Facebook memes – leave this stuff to the people who spend their lives researching it, and seek media sources who attribute peer-reviewed scientific journals or mainstream medical professionals."
Dr Sara Hassan, Paediatric Medicine Resident, PhD in Paediatrics at The University of Melbourne, gave a talk in November 2016, at the Australian Albanian Islamic Society Women's group debunking myths associated with vaccinations. At the talk, Dr Sara said that medical professionals take an oath of non-maleficence, that is a pledge to do no harm.
This principle is encompassed by the Hadith of the Prophet (s) 'There should be no harm nor reciprocating of harm'.
Dr Sara is an expert in these matters of vaccination, as both a medical practitioner and a research scientist.
We should be listening to the advice of experts in our Ummah like Dr Sara, and heed the warnings of Dr Nasya about the perils of getting your knowledge from social media.
[1] Transformation of impurity into another substance that is different in its properties and qualities, such as transformation of oil into soap and the like, or consumption of a substance through manufacturing as well as change of its essence and qualities is considered as an acceptable method in the Islamic jurisprudence in order to regard it as a substance that is pure and can be utilized for various purposes.
PreviousInconsonance of free trade agreements with economic theory
NextJustice, where art thou?
Hyder Gulam
Hyder Gulam is a qualified nurse, lawyer, an accredited mediator as well as a Fellow of the Royal College of Nursing in Australia with postgraduate qualifications in business/management, law, nursing and Islamic studies. He is the founder of the Muslim Legal Network. He has served for close to 10 years as an officer with the Royal Australian Air Force.
The power of social sciences to solve society's problems
Study Tip 3: Using your time at school efficiently
Great Community support after arson attack on Toowoomba Mosque
Workplace Relations Framework: Recommendations


text:
Q: numbered menu out of dictionary<> I am trying to figure out how to Console.WriteLine a dictionary that is numbered.
CollectionManager shoppers =
     new CollectionManager
     {
         Carts = new List<Inventory>(),
         Dictionary = new Dictionary<string, List<Inventory>>()
     };

And the method I have tried:
public static void DisplayShoppers(CollectionManager shoppers)
{
     List<string> temp =new List<string>();
     temp = shoppers.Dictionary.Keys.ToList();
     for (int i = 0; i < temp.Count; i++)
     {
         Console.WriteLine((i + 1) + ". Name: " + temp[i]);
     }

     Console.WriteLine("Pick a card to Shopper: ");
     int index = int.Parse(Console.ReadLine());
     if (index > temp.Count || index < 1)
     {
         return ;
     }

     temp.RemoveAt(index - 1);
}

It kind of works? but it is only printing the first letter of each entry in the dictionary.
switch (choice)
{
    case 1:
        Customers temp = CreateCustomers();
        shoppers.Dictionary.Add(temp.ToString(), new List<Inventory>());
        break;
    case 2:
        DisplayShoppers(shoppers);
        break;
}

//method for creating customer
static Customers CreateCustomers()
{
    Console.WriteLine("Create a Customer.");
    string name = Console.ReadLine();
    return new Customers {Name = name};
}

A: The code seems to be correct in terms of displaying full customer names in the console.
According to the conversation in comments, if You want to remove selected Customer from the Shoppers collection, You can change the line:
temp.RemoveAt (index-1);
into
shoppers.Dictionary.Remove(shoppers.Dictionary.ElementAt (index-1).Key);
This solution, however, requires additional search in the Dictionary only to find key of the item to remove. Consider keeping mappings between item's index and the item itself or just changing the dictionary to a List<Customer>.


text:
Q: Goroutine crashes silently I'm having some issues with a script of mine that dies silently once I try to make an existing function a goroutine. It seems if there is only a go routine in the main function then it doesn't run. Why is that?
After some fooling around I tried to reproduce the issue.
Heres a simple case from tour of
https://play.golang.org/p/78MQ90pp5L
package main

import (
    "fmt"
    "time"
)

func say(s string) {
    for i := 0; i < 5; i++ {
        time.Sleep(100 * time.Millisecond)
        fmt.Println(s)
    }
}

func main() {
    go say("world")
    say("hello")
}

If I comment say("hello") the program exits prematurely.
Can someone explain why?


The Working White English Bulldog Association (WWEBA) mission is to provide breeders and owners with the means to permanently register, record the heritage of, and ultimately preserve the future of the White English Bulldog.
The White English Bulldog is also known as: English Whites, Southern Whites, Old Southern Whites, Hill Bulls, American Bulldogs (forebearer of the original American Bulldog), and several additional names according to the location from which they came. The White English Bulldog has always been, and continues to be, a farm utility dog, as well as a trusted family guardian and companion.
First and foremost, the WWEBA breed standard requires the White English Bulldog to be of stable temperament, while possessing the structural and athletic ability required for farm utility work. The WWEBA breed standard reflects the ideals of foundation breeders. These foundation breeders are individuals who have preserved the White English Bulldog, mainly in the southern United States, for many generations.
The Working White English Bulldog Association does not condone any form of training of a White English Bulldog for the purpose of being aggressive toward any human being. Any associated formal activity, ie: bite work, man work, protection training, Schutzhund, Ring Sport, etc... is prohibited. Anyone engaging in these activities may be permanently banned from registering their White English Bulldogs with the WWEBA. Furthermore, anyone engaging in these activities with WWEBA registered White English Bulldogs will have all registrations permanently revoked.
Let it also be known that the Working White English Bulldog Association will permanently ban any individual using White English Bulldogs for dog fighting.
* As is stated on all WWEBA official forms: "The Working White English Bulldog Association reserves the right to revoke registration on any dog in the event that any false information has been knowingly used to register the animal. The Working White English Bulldog Association reserves the right to deny registration to any puppy and /or dog that does not comply with our accepted breed standard."
Founded by a group of devoted, like-minded individuals, the Working White English Bulldog Association is dedicated to recording the history of this versatile foundation breed, and securing its place in the future.
Please enjoy your visit and know that your comments or questions are welcome!


text:
Guide for Small Community Water Suppliers and Local Health Officials on Lead in Drinking Water
Ebook only
Available as an ebook
Please purchase via www.iwaponline.comOpens in new window
Also part of Water Intelligence Online Digital Reference Library
Standard ePrice: £0.00
+ VAT
Access ebook
Editor(s): Colin Hayes
Categories: Health issues, Water resources / environment, Water supply & treatment
Series: Best Practice Guides on Metals and Related Substances in Drinking Water
This PDF guide is free to download and supplements a book, the Best Practice Guide on the Control of Lead in Drinking Water.
This Guide for Small Community Water Suppliers and Local Health Officials is one of a series produced by the International Water Association's (IWA) Specialist Group on Metals and Related Substances in Drinking Water. It is an abbreviated compilation of the wide range of scientific, engineering, health and operational issues concerned with the control of lead in drinking water in small water supply systems.
The IWA Specialist Group is supported by members from 26 European countries, Canada and the United States. It is an active research network and has regularly convened international conferences and seminars. It has close working links with the World Health Organization, the European Commission's Joint Research Centre, Health Canada and the US Environmental Protection Agency. The IWA Specialist Group developed out of COST Action 637 (www.cost.esf.org), a European research network.
The Guide is supported by a two-day technical training course and a more comprehensive Best Practice Guide on the Control of Lead in Drinking Water (IWA, 2010). Information about training, the Best Practice Guide and the research network in general is available from www.meteau.org
This Guide for Small Community Water Suppliers and Local Health Officials explains why lead in drinking water may still be a threat to public health in small communities. It is aimed at Local Health Officials and the operators of drinking water supply systems that serve small communities. Its objectives are to raise awareness, to provide a basis for assessing the extent of problems, and to identify control options.
Best Practice Guide on the Control of Lead in Drinking Water
Part of Metals and Related Substances in Drinking Water Set - buy all six books...
Best Practice Guide on Sampling and Monitoring of Metals in Drinking Water
Editor(s): Adam Postawa
Best Practice Guide on Metals Removal From Drinking Water By Treatment
Editor(s): Mustafa Ersoz
Lisa Barrott
Part of Metals and Related Substances in Drinking Water Set - buy all six books together...
Best Practice Guide on the Control of Arsenic in Drinking Water
Editor(s): Prosun Bhattacharya
David A. Polya
Dragana Jovanovic
Nanotechnology for Water and Wastewater Treatment
Editor(s): P. Lens
J.Virkutyte
V. Jegatheesan
S. Al-Abed
Seung-Hyun Kim
The rapid development of nanoscience enables a technology revolution that will soon impact virtually every facet of the water sector. Yet, there is still too little understanding of what...
TECHNEAU: Safe Drinking Water from Source to Tap
Editor(s): Christian Kazner
The best papers from the three-day conference on Safe Drinking Water from Source to Tap June 2009 in Maastricht are published in this book covering the themes of challenges of the water sector and...
Health Effects of Metals and Related Substances in Drinking Water
Author(s): Professor Margherita Ferrante
G. Oliveri Conti
Z. Rasic-Milutinovic
Dusan Jovanovic
Metals are inorganic substances that occur naturally in geological formations. Naturally occurring metals are dissolved in water when it comes into contact with rock or soil material. Some metals...
Best Practice Guide on the Management of Metals in Small Water Supplies
Editor(s): Matthew Bower
Colin Hayes
The management of small water supplies presents a unique challenge globally, in countries at all stages of development. A combination of lack of resources, limited understanding of the risks and...


One Track Brain is back with his third EP 'Kitten Play/Dust Devil' on the OTB records imprint. Jazzy drums and the trustworthy 808 kick drum are at the heart of this energetic and playful new 12'.
On the A-side, 'Kitten Play', a whirlwind of rhythms evokes an untampered lust for life. A spontaneous structure keeps the kittens in check.
On the B-side, we find 'Dust Devil', another energy pill based primarily around rhythm. A sweet little melody is juxtaposed against a thick layer of bustling drums. A stormy track with a mermaid's melody calling out from afar.
One Track Brain, clearly not a rookie, remains a shadowy quantity with the focus wholly on his music.


Subject: LongIsland.com - Your Name sent you Event details of "Success Hub Presents: Secret Knock"
Success Hub's mission is to educate, inspire, and motivate entrepreneurs, and they have created a special event to accomplish exactly that. If you hunger for progress, thirst for knowledge, and are ready for excellence, then Secret Knock is the place to be.
Imagine an experience where you can mix, mingle, and meet a gathering of positive, like-minded champions who share your dreams, aspirations, and ideas. Surround yourself with a gathering of leaders, visionaries, action-takers, and boundary-breakers in this special one-night event.
On Wednesday, November 9th you will make friends, share stories, gain knowledge, play games, enjoy music, and have fun while getting things done.
Tables of 10 are $450.


Developed in collaboration with Starvation Alley Cranberry Farms, this liqueur celebrates a local industry steeped in tradition and those farmers who dare to be different. Using our wheat spirit, locally harvested cranberries, and just the right amount of sugar, the spirit is warm and bright with a tart kick. Great in a glass of bubbles, mixed into a margarita, or as a splash of color in a whisky-cider cocktail, this liqueur can find a home behind any bar.


Do you know the Love of the Father?
Do you know how He cares for you?
He's the one to carry you through?
And you think there's no way to turn back.
And blast you with another attack?
To pen the most important words you'll hear.
As I whisper this message in your ear.
He's always kept you in His heart.
On the road to a brand new start.
As you leave all your past hurts behind.
That you've searched forever to find.
Once you experience His amazing grace.
With all wrongs and regrets erased!
A love that will never compare.
Humility brings repentance — repentance brings forgiveness.
With Forgiveness: YOU ARE LOVED!
Have a great week and always remember, YOU ARE LOVED!
What a lovely, warmhearted poem, Del. Thank you for this. I kinda needed it.


text:
"To be ignorant of what occurred before you were born is to remain always a child. For what is the worth of human life, unless it is woven into the life of our ancestors by the records of history? History is a "guide to life" (magistra vitae) for politicians and top-tier corporate decision makers, their advisers, and for citizens"
The hands-on management of the admixture of increasingly complex contemporary global problems and concerns, some of which reach back into different periods in time, requires proper and systematic consultation and understanding of their gradual evolution over time.
It with a deep appreciation of the fact that we cannot comprehend the present without a thorough understanding of that past that I approach some of the intractable problems of contemporary society, among them, armed conflict and postcolonial state-building in Africa and beyond.
This, then, calls for the deployment of the critical human science of applied history. This means tapping the goals and methods of the empirical approaches of the study of the past to tackle and mitigate, if not resolve, contemporary global challenges that face us. As historians Jo Guldi and David Armitage urge in their forthcoming book (The History Manifesto, November 2014) history ought to regain, and sit firmly on the saddle of, its role, and classical spirit of inspiring the longer view, and thence, the habit of informing the public sphere. As they have so eloquently stated, this "was the classical spirit in which Machiavelli and his contemporaries wrote their histories, whether of ancient Rome or of their own city-states such as Florence, taking lessons from Rome's arming of the plebeians or its strategies for territorial expansion when considering the destinies of their communities. It was also the aim of historians in the Enlightenment, among them David Hume, Voltaire, and even Adam Smith, whose Wealth of Nations was at its heart a history of Europe and its overseas empires written to inform debate about the commercial future of Europe and its colonies and published in the fateful year of 1776."
After all, history is not a mass or an amassment of "yawn-enforcing" facts. Rather, it is the sum of all lived human experience and existence that's alive all around us. Indeed, history is an organic movement of socio-economic and political processes. This approach and critical analysis is "applied history" that sees all human history as a process of change and development. This is the expertise that I bring to various consultancies; projects; and research to better inform policy and choices in middle- and high-level decision-making process to chart the future.
100 to 5,000 Years Existence Perspectives: Research-based Planning & Strategy
Through masterful application of longue durée history, it is possible to put into perspective human imprints of existence of between 1,000 and 5,000 years or more, centuries and millenia, thus deeply understanding the past to chart out long futures be they public, corporate or institutional.
In stepping up to, and in confronting, global problems and challenges, the lessons of history are instructive and imperative. I deploy applied history to analyze archival data empirically to produce actionable knowledge. The subsequent result are ideas that can be turned into action: that is tangible and actionable deliverables that can be used to better understand the present and help policy makers to map out the future with regard to the following areas of service:
Military history or history of specific armed conflicts
Legal/Constitutional history and reforms
Expert long-term election monitoring (political and media situations; election administration; and campaign environment)
Strengthening social cohesion, management of ethnic diversity and inculcating harmonious coexistence
Agricultural policy and (international) development
Historical research and interpretation
Memory, memorialization, conflict resolution, truth, justice & reconciliation and peace-building processes
Security sector reforms
Program/project monitoring and evaluation
If you have a project, please contact me via email at kariuki.githuku@africanperspectives.co.ke with a detailed description for a quote.
"The mission of the humanities is to transmit questions about value – and to question values – by testing traditions that build up over centuries and millennia. And within the humanities, it is the discipline of history that provides an antidote to short-termism, by giving pointers to the long future derived from knowledge of the deep past."
-David Armitage and Jo Guldi co-authors of The History Manifesto (2014)
Africa African Perspectives African Studies Association-UK African Studies Association -US Böll Stiftung Colonialism elections Ethnic Politics EU Europe European Union Ford Foundation GEMA German Cultural Centre Heinrich Insecurity Kenya Kenya Elections Kenya Goethe-Institut Kenya Police Kenya politics Majimbo Mau Mau Memory Mombasa Republican Council MRC Nobel Peace Prize Nobel Prize ODM Personal Reflections Perspectives Political Movements political parties politics Raila Odinga Regionalism Security Shootings Social construction Social reality Social relations TNA U.S.-Africa Foreign Policy United States Violence
Feeds: African Perspectives
Feeds: kariuki githuku
Dearth of the Political Party in Kenya
How to Play "Father": Raila's Lost Moment?


Here's the latest. As before, if you want to be on the early-bird notification list for further info and pre-orders, drop an email to jim (at) five12 (dot) com.
- USB A jack for connecting MIDI controllers.
- Much better Pitch CV DACs (with a much larger voltage range: -2 to +8 volts).
Front Panel: The front panel design has been finalized, and I have some panels I will be using for beta units.
Bootloader : there is now a proper bootloader that can load new firmware from the micro-SD card. Not a very exciting item, but still very important.
Sync: I have DIN sync generation working through either a pair of the trigger outputs, or via the STG Sync Out connector on the back of the main PCB. I also have DIN Sync input working via the STC Sync In connector (also on the PCB). You will also be able to use an STG Soundlabs Time Buffer module or the Jack Expander module (more below) to send/receive DIN Sync. MIDI Sync in and out are coming next.
Run, Clock, Reset : In the Rev3 hardware, these jacks became bi-directional. They can all currently be used to generate clock at variety of rates (Sync48, Sync24, and a range of options fro 32nd notes to 32 whole notes). The first jack can also be set to output run/stop. Input mode options are not implemented yet, but will involve various trigger options for the individual sequencer parts. I will also be adding settings to use these jacks as the Gate Outs for parts -- very handy for drum programming.
Power consumption: I'm seeing an average of 115mA draw on the +12V line, and 15 mA on -12V, this goes up a bit depending on how active the OLEDs and LEDs are -- I'll say budget 140mA on +12 when not using USB. Since USB A jacks must provide power, consumption will go up when in use -- budget 200-400mA total on +12 in that case -- depending on what you plan to use. I'll have more detail on this once I've tested more devices. The most draw I've seen is 345 mA total when charging my iPhone.
There are currently 5 units out for beta test, with a few more going out in a few weeks.
There's still a fair bit of work needed on the drivers for the USB ports: The USB B port -- the one that would go to your computer -- needs a combo mass-storage/midi driver, and the USB A port has a provisional MIDI driver that needs some work to integrate it properly into the sequencer.
Modulation Inputs: I have the first of these working, and should have the second working soon, just need to sort out some firmware details. You will be able to use these to modulate sequencer parameters via CV.
Projects, Scenes & Presets : Still a good amount of work to complete here, but all tasks that I am familiar with: Syncing preset changes to beat/bar boundaries, project file management, scene and preset naming, etc.
Rec Mode: I need to work out some details on how the Step Recording functions across parts, and I also want to add both local and global transpose modes.
The Jack Expander: This is a 12hp add-on module, it adds 4 more 'voice' outputs (Pitch, Gate, Velocity CVs), 8 bi-directional triggers, MIDI I/O on DIN jacks and DIN sync. I received the first prototype of this module right before NAMM, and had just enough time to get the gate outputs working.
I will start taking pre-orders once the hardware and drivers are finalized, and the sequencing firmware is finished. There will be one more hardware revision on the main board. So far the only changes are a couple of small things related to power management. I plan to put in a PCB order late February (in case any further feedback from beta test requires a hardware change) and should receive boards in late March.
On the driver font, all the bits related to the displays, front panel, MIDI, DACs and SD Card are working smoothly, so that just leaves USB. As for the sequencing code, the big things left are listed above, but there are also many other details to update as well.
Wow, that's all very exciting!
Can I ask what the resolution of the pitch DACs is?
The current test units output -2 to +8V, but based on feedback and some long discussions with Chris Meyer over at learningmodular.com, I will be shifting it down a bit to -3V to +7V.
Just wondering how things were going on the Vector? I saw a video with Chris Meyer, who seemed pretty pleased with his beta version, but apart from that, all very q. Also Numerolgy 5?


SEATTLE, Feb. 2, 2016 /PRNewswire/ -- Fathom, the pioneer in social impact travel and Carnival Corporation's (NYSE/LSE: CCL; NYSE: CUK) 10th and newest brand, today announced the availability of a buy one get one (BOGO) special on Fathom sailings to the Dominican Republic that gives the first and second travelers a discount of 50 percent off per person. Travelers may book the BOGO offer through Feb. 29 for Dominican Republic social impact sailings from April through June of 2016. April – May rates begin at $628 per person and June rates begin at $733 per person to the Dominican Republic.
Unlike traditional BOGO offers, Fathom is extending the offer to include the second traveler at an unbeatable price. Travelers can build a community with like-minded travelers, become immersed in another culture, and work alongside one another to create enduring social impact, while also setting aside time to take advantage of relaxing and recreational activities. This offer makes it easier for travelers to bring along family members, loved ones or good friends on an incredible journey of discovery, leisure time and personal enrichment for the price of one.
"This offer is a great way for two friends, loved ones or family members to be among the first to sail on a Fathom voyage to the Dominican Republic," said Tara Russell, president of Fathom and global impact lead for Carnival Corporation. "With our exceptional BOGO offer, we are welcoming travelers from all walks of life to unleash their personal gifts and talents and deeply impact the world."
Varying from economic, educational and environmental activities, travelers can participate in a wide range of exciting impact activities both onboard and on-ground, while exchanging cultures and customs with Dominican families. Impact activities include building water filters for Dominican homes; helping a women's cooperative produce artisan chocolates; improving homes and common areas in impoverished communities; assisting arts and crafts entrepreneurs; connecting one-on-one in the homes of Dominican host families; participating in community English-language retention activities; and supporting reforestation efforts.
In addition to participating in array of social impact activities, travelers to the Dominican Republic can experience memorable recreation, leisure and sightseeing activities. Whether exploring ancient ruins, interacting with abundant marine life in the crystal clear waters to lounging in the sun-soaked stretches of surf and sand, travelers will have the opportunity to make the most of their time in the Dominican Republic. They will also have access to select Amber Cove excursions. The port will offer numerous sea and landside experiences including several beach getaways, kayak, paddle board and snorkeling tours, ATV-like terracross buggy expeditions, Puerto Plata tours, helicopter rides, fishing trips, horseback riding, deep sea fishing tours and catamaran sailings.
Fathom's BOGO offer is available for all stateroom categories. For more information or to book, travelers can call 1-855-932-8466 or their travel professional by February 29 and reference code "FA." BOGO is not available for online bookings on fathom.org or combinable with the D.I.B.S. promotion. Gratuities are not included. Taxes, fees and port expenses are also not included, and are currently $208 per person, and are subject to change.
BOGO prices for the seven-day trips to the Dominican Republic start at $628 per person, excluding taxes, fees and port expenses and including all meals on the ship, onboard social impact immersion experiences, three onshore social impact activities and related supplies. Prices will vary by season. To secure a spot on future sailings, a fully refundable $300 per person deposit is required for all cabin categories and occupancy levels. Final payment is due 90 days prior to departure.
Prices for seven-day itineraries to Cuba start at $1,800 per person, excluding Cuban visas, taxes, fees and port expenses and including all meals on the ship, onboard social impact immersion experiences and on-the-ground cultural immersion activities. Prices will vary by season. To secure a spot on future sailings, a fully refundable $600 per person deposit is required for all cabin categories and occupancy levels. Final payment is due 90 days prior to departure. To reserve a spot on future sailings, travelers may call 1-855-932-8466 or work with a travel professional. Learn more at www.Fathom.org.
Fathom, a new brand in the Carnival Corporation family, is the pioneer of impact travel, a new category of travel that will offer consumers authentic, meaningful travel experiences to enrich the life of the traveler and work alongside locals as they tackle community needs. Fathom is unique in that it leverages Carnival Corporation's expertise and scale for a one-of-a-kind business model to create long-term collaboration with its partner countries, allowing for sustained social impact and lasting development. Fathom will serve the sizable and growing market of potential social impact travel consumers – approximately one million North Americans – in addition to global travelers already pursuing service-oriented travel experiences worldwide.


Most of us agree that sims are great for training. So, why do we spend the least time necessary in them to get legal? Shift your thinking to proficiency, and "legal" takes care of itself.
What's a Sim Good For?
There is an increasing number of tools to expand the simulation experience for GA pilots. I mentioned three in the article.


Last Thursday Playcentre was packed to the rafters for their Halloween party. The children had an amazing time making decorations and then hanging them up the Lodge, baking cakes and biscuits, having a party and going out 'trick or treating' with the playcentre staff. Huge thanks to Vicky, Jackie, Fahima and Laura for making the event so much fun for the children, and to Morrisons, Marks & Spencer and Iceland for being so generous when the children and staff went into the shops. Also, huge thanks to Kaleb's mum for all her contributions to the party.


PHILADELPHIA – Today, the City of Philadelphia officially announced plans to develop a Bethel Burying Ground Historic Site Memorial.
Luminaries and flowers were laid to mark the footprint of the Burying Ground and honor those laid to rest.
The Bethel Burying Ground Historic Site Memorial will honor the 3,000 to 5,000 individuals interred at the site who represent the founding generations of the nation's largest and most important African American population of the 18th and 19th centuries. The historic site links the African American experience to Philadelphia's role in the birth of the nation. "It is imperative that we develop a meaningful, physical memorialization of this historic site that reflects its role in our City's history and honors those laid to rest there," said Mayor James Kenney.
"The City of Philadelphia welcomes this opportunity to honor the thousands interred at this site. Whatever the memorial design turns out to be, it is important that it recognizes and honors the past, while remaining a gathering place for Philadelphians," said Michael DiBerardinis, Managing Director of the City of Philadelphia.
"This site has deserved recognition for years and the Friends of Bethel Burying Ground and the Avenging the Ancestors Coalition are pleased that the City is finally taking steps towards giving proper respect to those interred," said Michael Coard, Friends of the Bethel Burying Ground Coalition and Bethel Burying Ground Memorial committee member.
This announcement is the first of several public events intended to educate the public about the Bethel Burying Ground and engage the surrounding communities in the purposeful portrayal of its history into a physical memorial. The City, together with the Memorial Committee, plans to undertake a thoughtful and transparent process to develop of a meaningful memorial that identifies this historic site and celebrates the lives of those interred there.
"It is meaningful to the Queen Village community to participate in this historic process while acknowledging the important role this site has played in the neighborhood," said Eleanor Ingersoll, President of the QVNA and another Bethel Burying Ground Memorial committee member.
Some members of the Memorial Committee with Mayor James Kenney.
The Bethel Burying Ground Memorial committee is comprised of stakeholders which include: Office of Arts, Culture and the Creative Economy; members of the Friends of the Bethel Burying Ground Coalition; historians; descendants of the interred; representatives of the Queen Village Neighborhoods Association; representatives of the Friends of Weccacoe Playground; representatives of Mother Bethel AME Church; and public artists.
For more information, contact Sarah Reyes, Sarah.Reyes@phila.gov, 215-686-6210 and Carrie Leibrand, Carrie.Leibrand@phila.gov or (215) 686-4478.


Mother Shahraz dead. Illidan be afraid.
► Mother Shahraz dead. Illidan be afraid.
Mother Shahraz and her illegal party was destroyed. Mother Shahraz was killed on our 2nd try ever. Congratulations to all that were in the raid or helped for this raid to happen.
Re: Mother Shahraz dead. Illidan be afraid.
mOOwalker takes some time to update = whine whine whine.
mOOlwaker updated the kill = Gz to raid.
yea great job guys 2 new bosses in 2 days is sweet. Only 1 pack ill illidan!!!


text:
Sixers Extend Coach Brett Brown
PHILADELPHIA- WTXF - The Philadelphia 76ers may be amidst an extended run of futility that's virtually unprecedented in NBA history, but clearly the team doesn't see that as a reflection on the performance of the head coach.
Coach Brett Brown has received an extension to his contract, the team announced Friday. Brown is in his third year as Sixers coach. A news conference was held at 5 p.m.
While Yahoo reporter Adrian Wojnarowski reported that the contract was for an additional two years and will now run through 2019, the Sixers did not announce terms of the deal.
"Brett has been everything we anticipated - and more - both as a basketball coach and a partner in building this program," general manager Sam Hinkie said. "His tireless work ethic, his daily desire to consistently improve, and his resiliency line up with our core values as an organization. It was not difficult to come to the decision to formally say we want to work with Brett Brown even longer."
The announcement comes a week after veteran NBA executive Jerry Colangelo was brought into the team as chairman of basketball operations.


text:
Q: How can i verify mastercard and visa card in my shopping cart project?
*

*My team working in a shopping cart project

*We have integrated First data payment Gateway

*Now we want to verify the master card and visa

*I need to authenticate the master card SecureCode based on the link given below

*http://www.mastercard.com/us/personal/en/cardholderservices/securecode/how_it_works.html

*Please provide any api or necessary information for doing the same

A: To validate a credit card is legitimate:

*

*Verify it against the Luhn Algorithm. (Will only validate the card number is in a valid format)

*Verify the card number against known Issuer Identification Numbers

*Perform an Authorization Only (aka AUTH ONLY) for $0.00 (or $0.01 if your processor does not support zero auths). This is the only guaranteed way to verify a credit card exists.

A: Hum, imho you need a payment provider to use credit card payment anyway - they'll give you a kind of api to check the data against.

A: To at least validate the code is valid you can give this a try:
http://www.notesbit.com/index.php/web-mysql/web-scripts/luhn-algorithm-in-c/

A: http://www.mobilefish.com/services/credit_card_number_generator/credit_card_number_generator.php
Check previous link it contains good description for luhn alog and have credit card generator


Detect empty parameters in ToolValidator?
This may be a dumb question, but how do you determine in the ToolValidator class whether an input parameter has been left blank?
Some of the parameters in my tool are optional in some cases, and required in others. I would like to raise an error when a field is left blank under certain circumstances.


text:
For job seekers For employers
For job seekers For job seekers For employers
ESG in action
Working as a contractor
Back to knowledge hub
Keeping people engaged and innovative when part of the workforce is remote
We share some top tips on how to keep your workforce engaged and innovative in a hybrid working world.
While many employers still want to see an on-site presence, and for some roles remote working isn't feasible, it has become a feature of working life that looks set to stay. According to an ONS Survey, 84% of UK professionals plan to continue a mix of working from home (WFH) and in the office.
For many, hybrid working was a positive manifestation of the pandemic, giving people far more flexibility and a better work-life balance. A survey of more than 12,000 professionals, by Tracking Happiness, found the ability to work from home increases happiness by up to 20%.
But remote working is also known to have its downsides and doesn't suit everyone. Its impact on mental health is an important topic. The NHS, for example, has a dedicated page, providing simple self-help tips. For many, working from home is isolating and Nuffield health says "80% of UK workers feel working from home negatively impacted their mental health". In another survey, of 2000 UK and US workers, 81% of under-35s would feel more isolated without time in the office, compared with 64% of those aged over 35.
So, what about innovation? Some feel fewer colleague distractions can help them focus, while for others face-to-face collaboration fosters more creativity. Although productivity might have increased during the pandemic – according to Forbes, innovation suffered. For others, hybrid working has actually made companies more innovative – Scientific American notes that remote teams "can gain an innovation advantage and out-compete in-person teams". Success or failure seems to be down to the practical steps businesses take. So, what can companies do to keep their people engaged, innovative, happy and thriving in today's hybrid working world?
Make innovation central to the business
Organisations tend to spend a very small percentage of their budgets on promoting innovation internally, says Forbes. For businesses to reap innovation rewards, they need to put more money into it. This, in turn, gives employees permission to think outside the box and not just follow the rigmarole of the normal working day.
Remember the importance of human interaction
Remote staff need to feel like they are part of a community and organisations should place a lot of value on emotional intelligence (EQ). Harvard Business Review (HBR) mentions the 'proximity principle', which means that people develop strong bonds with people at work, therefore working harder as their workplace is more than just an office; it's a social environment with friends. "Friendships really matter to employee engagement," it notes. So, what can employers do to counteract a lack of this? Invest time in "one-on-one interactions," says HBR.
According to Deloitte insights, the sudden transition to remote working during the pandemic was successful because existing social ties and work peer relationships helped to sustain productivity. "Making sure that this social capital continues to thrive in a hybrid environment will be critical," it adds. On the innovation side, employees who "feel free to share their emotions with one another – both positive and negative – are more likely to innovate and come up with creative solutions to problems," says Forbes. Therefore, making EQ central to the business will likely make remote workers more engaged, and more innovative as a result.
Introduce robust support systems
Managers are key to enforcing new workplace measures, to improve employee engagement. But they need support too. In a Gallup survey, managers were reported to have taken the biggest emotional hit during Covid-19, so facilitating them to support others properly is vital for workplace engagement. "Once managers have the support they need, they can take steps to foster emotional connection, team bonding and fun to compensate for the loss of proximity in the office," says HBR.
According to Forbes, one important area to invest in is remote management training, to ensure managers have the tools they need to manage remote teams well. When it comes to innovation, managers can set the tone to foster this too. Trusting staff by giving them permission not to look at notifications all the time, for example, should allow for more focused work and problem-solving, which is needed to innovate effectively.
Meet in person regularly
If possible, aim to meet in person with your staff and spend more time planning off-site meetings. Regular in-person meetings also fulfil the human interaction need – the Thought Leadership Institute notes "a sense of community in the workplace fulfils a basic human need for connection."
Use technology to help
Organisations should look at the role 'collaborative technology' such as Microsoft Teams, Slack, or even virtual reality software can play, says PWC. Such tools make it easier for hybrid workers to communicate and feel included. These tools are particularly vital for staff who work remotely all the time. Slack, one of the most important hybrid working communication tools, says that "recent history has shown us that we can be effective, creative and productive working from anywhere". But we still need to feel connected.
For help managing your workforce mix, talk to one of our team today.
Highlights from STEM 2022
As we kickstart a new year, we also want to take time to remember some of the exciting STEM highlights and innovative happenings from 2022 that have helped make the world a better place.
How IT professionals are the enablers of our time
With STEM Day on 8 November, it's time to appreciate the value those working in technology bring to us all...
Logistics and retail – the role of CIO in a changing sector
The retail and logistics sector is evolving and so is the role of Chief Information Officer (CIO). We delve into these changes and consider how tech leaders can build the right teams to support them....
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ESD - Are there multiple scaling regimes in Holocene temperature records?
Are there multiple scaling regimes in Holocene temperature records?
Abstract. The concept of multiple scaling regimes in temperature time series is examined, with emphasis on the question whether or not a monoscaling model with one single scaling regime can be rejected from observation data from the Holocene. A model for internal variability with only one regime is simpler and allows more certain predictions on timescales of centuries when combined with existing knowledge of radiative forcing. Our analysis of spectra from stable isotope ratios from Greenland and Antarctica ice cores shows that a scale break around centennial timescales is evident for the last glacial period, but not for the Holocene. Spectra from a number of late Holocene multiproxy temperature reconstructions, and one from the entire Holocene, have also been analysed, without identifying a significant scale break. Our results indicate that a single-regime scaling climate noise, with some non-scaling fluctuations on a millennial timescale superposed, cannot be rejected as a null model for the Holocene climate. The scale break observed from the glacial time ice-core records is likely caused by the influence of Dansgaard–Oeschger events and teleconnections to the Southern Hemisphere on centennial timescales. From our analysis we conclude that the two-regime model is not sufficiently justified for the Holocene to be used for temperature prediction on centennial timescales.
How to cite: Nilsen, T., Rypdal, K., and Fredriksen, H.-B.: Are there multiple scaling regimes in Holocene temperature records?, Earth Syst. Dynam., 7, 419-439, https://doi.org/10.5194/esd-7-419-2016, 2016.
In this article it is discussed how temperature variability on centennial timescales and longer can be described in a simplistic way. By analysing the scaling in late Holocene temperature reconstructions and longer temperature records from Greenland and Antarctic ice cores, we find that the choice of model depends heavily on the data material and timescale one chooses to emphasize. Ignoring data beyond the Holocene seems plausible when predicting temperature, but not for other purposes.


As LIRS's Migrant and Refugee Leadership Academy approaches, I am excited to share the experiences of some of the courageous new Americans that will be participating in the Academy. Mayom Bol Achuk, a former refugee from South Sudan who now lives in Maryland, will be one of these participants. In today's post, Mayom writes how he has become an "agent for change" for others who are forced from their homes.
I am part of the most recently resettled refugee groups known as Lost Boys of Sudan in America, a Dinka by tribe, and now a South Sudanese-American by nationality. I was born and raised, as were many boys of my age, to tend cattle and practice backyard hunting. Although modern education was alien to the culture I was brought up in, life was very interesting and fully enjoyable. When I was four years old, my family embraced Christianity and abandoned their ancestral gods.
In 1986, I started my education at my church school where I learned letters in my native language of the Dinka tribe. This church school was only meant for learning how to read the Bible in the Dinka language. There was no paper or chalk but only charcoal or small sticks that were used on animal skins or the dirt. After we were forced to flee Sudan in December of 1987, we went to a refugee camp in Ethiopia, where we started our classes in English, Arabic, and mathematics. Educational supplies were scant. Two pupils shared one exercise book and pencil: each was split, and one eraser was shared.
In the Kenyan Kakuma refugee camp, the situation changed and we studied six additional subjects that were completely new to us. I started in third grade and reached twelfth grade before I finally left to resettle in the United States. In America, I thought I would continue high school but was told that I needed to go to college instead of high school since I was of college age. However, to meet the requirements for college admission, I had to take a GED exam. After I passed my GED exam I went to Grand Rapids Community College for my associate degree. After graduation, I transferred to Calvin College for another two years for my bachelor's degree. I attended Liberty University for another two years of graduate studies. Right after Liberty University, I went to Eastern University for another graduate program before relocating back to South Sudan to help a nation and peacebuilding process and the fledging educational system.
I've worked hard since I came to the United States. I have been studying and often working two to three jobs to support myself, my family members in South Sudan, as well as help support the Sudanese community in America. While in South Sudan, I was working as a Joint Development Fund Coordinator for Borlaug Institute for International Agriculture at Dr. John Garang Memorial University of Science and Technology. Unfortunately, I was not aware that the newly established government of South Sudan would eventually turn against the people and fail to deliver the much-awaited democratic system of governance there. Unequivocally, I opted to leave the country again due to fear for my life after being threatened five times at gunpoint in Juba, the capital city. I was evacuated back to the United States due to the current civil war in the newly independent Republic of South Sudan and have now decided to reside in the Washington, D.C. metropolitan area.
Since I can't go back home under the current leadership, I am still part of the nation-building process and change for good governance in South Sudan. I hope change will come to South Sudan as soon as the current generation of former rebel commanders and old guards, who are now the national ministers, are gone.
In deciding to attend this training [LIRS Migrant and Refugee Leadership Academy], I realized that I don't have to be in South Sudan to bring change, solve my people's problems, or advocate for change in the government of South Sudan. I can help form strong communities of Sudanese people in the areas where they have relocated. My goal for advocacy is to reduce or stop any government policy that creates another generation of child soldiers and increases refugee populations worldwide. I have dedicated myself to help other refugees feel welcomed in this great land of opportunity, just as I was welcomed. I will continue to constructively fight for the human rights of those who are still held hostage in oppressive political systems. I am not only honored to be selected as a participant in this Leadership Academy but want to be equipped as an agent of change for those who are currently in my previous situation.


First Night Boston was the original First Night, but Worcester, Sandwich and Needham are among the communities that offer their own celebrations.
SANDWICH – The newest, First Night Sandwich, hosts its second celebration in and around Town Hall Square. Festivities include a revelers' parade, ice sculptures and performers. The highlight is a light extravaganza at the Dexter Grist Mill on Shawme Pond, and the illumination of the 2014 Tower of Lights at 9 p.m. Buttons are $10 for adults and $6 for children ages 3 to 12. For information, go to www.firstnightsandwich.com.
NEEDHAM – New Year's Needham offers fun for almost any taste: children's entertainers, magicians, puppet shows, opera, classical, folk and soul music, square dancing, a comedian and a Frank Sinatra impersonator. It culminates with a 21-plus dance party, with cash bar, from 9:30 p.m. to 12:30 a.m. Buttons are $5; the party costs $15 through Dec. 27 and $20 after. For information, go to www.newyearsneedham.org.
WHITMAN – Whitman's First Night is a free, outdoor New Year's Eve bash. The Whitman Winterfest Committee has been organizing this event with the help of funding from Nestle. There will be three live bands starting at 9 p.m. and other activities. At the stroke of midnight, a very large replica of a Nestle Tollhouse Cookie will be lowered in Whitman Center from 75 feet in the air, along with a pyrotechnics display. For more information, call McGuiggan's Pub at 781-447-7333.