text:
\section{Introduction}

The effect of impurities and quenched disorder in condensed matter
represents an important problem both because of the ways in which
disorder can change fundamental properties of a system and because any
real material will inevitably possess imperfections.  Studies have shown
dramatic consequences of disorder, such as the destruction of ordered
phases and the introduction of new exotic ones, deviation from the
universal behavior around transition points, and sometimes even the
enhancement of useful material properties.  Liquid crystals, due to
their soft elasticity, sensitivity to surface interactions, and
experimental accessibility, provide an excellent opportunity for
studying the effects of quenched disorder, which can be introduced
experimentally through confinement of the liquid crystal to random
porous media.  A particular focus in this area has been the study of
smectic liquid crystals in silica gels.  In a detailed theoretical
treatment of smectics in such random environments, Radzihovsky, Toner,
and coworkers identified two forms of random-field disorder that the
confinement introduces to the smectic -- random orientational fields
that couple to the nematic director and random positional fields that
couple to the smectic density wave~\cite{radz_toner1,
 radz_toner2,radz_toner3,radz_toner4, saundersthesis}.
One conclusion of their study was that the smectic phase is
unstable to arbitrarily weak random-field disorder, consistent with
expectations for a phase that breaks a continuous symmetry in three
dimensions.  Experimentally, considerable work has been dedicated toward
investigating smectics in two types of silica gels, chemically rigid
aerogels~\cite{clark-science,lei,finotello-gel,bellini-aerogel-light}
and colloidal gels formed from aerosil particles~\cite{park,
finotello-sil,paperI,paperII,Liang,finotello-pre,zhou,Mertelj, theon,germano,
aerosil1,aerosil2,aerosil3,aerosil4,aerosil5,aerosil6,clegg8S5,clegg8OCB,
Larochelle,8CBrheo}.  The chemical compositions and structures of the
two gels are very similar, but the hydogen-bonded aerosil gels have the
potential to access a weaker regime of disorder.  Utilizing a wide range
of probes, experiments on smectics confined to aerogels and aerosil gels
have detailed the consequences of the confinement for the nematic and
smectic phases, supporting the general picture that the gels impose
random-field disorder that destroys the nematic to smectic transition.

Among the predictions for smectics confined to gels is the potential
formation of topologically ordered, ``Bragg glass'' phases that are
distinct from the high-temperature nematic phase by the absence of
unbound dislocation loops.  Considerable evidence from theory and
simulation supports the existence of a topologically ordered state with
algebraic decay of correlations in the three-dimensional (3D) random
field XY model at low temperature~\cite{giamarchi,huse,fisher}.
(However, a recent argument based on the functional renormalization
group approach has questioned the existence theoretically of such a
phase in 3D XY systems~\cite{tarjus}.)    Since the nematic to smectic-A
(N-SmA) transition breaks 3D XY symmetry, one might hence expect that
smectics confined to gels would be good candidates for realizing such an
``XY Bragg glass'' phase.  Considering this possibility theoretically,
Radzihovsky and Toner have concluded that the orientational random
fields coupling to the nematic order and the soft elasticity of the
smectic make smectics confined to gels distinct from standard random
field XY systems.  Instead, they have introduced the possibility that  a
``smectic Bragg glass'' phase,  which has short range correlations and
is qualitatively different from the XY Bragg glass, might form in
smectics confined to gels~\cite{radz_toner1}.  However, the theoretical
argument for the stability of the smectic Bragg glass is inconclusive,
and experimental evidence for the phase in smectics confined by silica
gels has been contradictory~\cite{clark-science,
paperI,paperII,clegg8OCB}.  Jacobsen, Saunders, {\it et al.}
have further argued that smectics confined to uniaxially strained gels
should fall into the universality class of random field XY systems and
hence should form an ``XY Bragg glass''  for sufficiently weak
disorder~\cite{radz_toner4, saundersthesis,toner_prl}.  The key
difference between isotropic gels and strained gels is the effect of the
orientational fields.  Specifically, if the strain alters the
distribution of orientational fields, causing them to suppress nematic
fluctuations at large length scales, then the smectic in strained gels
should theoretically exhibit an XY Bragg glass, provided the positional
random fields are sufficiently weak.  Recent additional theoretical
predictions regarding the smectic-A to smectic-C transition under
confinement in strained gels has highlighted the potential for smectics
in such an anisotropic environment to display exotic phase
behavior~\cite{toner_prl}.

In an effort to understand the separate effects of orientational random
fields and positional random fields on the N-SmA transition and to test
for the presence of an XY Bragg glass phase, we have conducted an x-ray
scattering study of smectic octylcyanobiphenyl (8CB) confined to {\it
aligned} aerosil gels.  The structure of these gels dramatically alters
the nature of the orientational fields, converting the random
distribution found in isotropic gels into a sharply anisotropic
distribution that macroscopically orders the nematic director.  This
anisotropy, or ``soft axis'', makes the gels a faithful experimental
realization of uniaxially strained systems considered by Jacobsen,
Saunders, {\it et al.}~~In this paper, we report an analysis of the x-ray
scattering results that indicates the presence of an XY Bragg glass
at low temperature for low densities of aligned aerosil.  The signature
feature of the XY Bragg glass is a power-law divergent smectic
scattering peak with a universal exponent.  We note that in a
preliminary report on our x-ray studies~\cite{Liang}, we concluded that
8CB confined to aligned aerosil gels did not exhibit such
characteristics of the XY Bragg glass phase.  As we explain below, by
adopting a physically better-motivated description of the behavior of
the thermal critical fluctuations  in smectics confined to aerosil
gels~\cite{Larochelle}, we find that the previous analysis is not
satisfactory in accounting for the smectic correlations at low
temperature.  Instead, when a finite nematic domain size is incorporated
into the analysis to reflect the imperfect nematic order in the aligned
gels, comparisons between the x-ray scattering results for low densities
of aerosil and the predictions for an XY Bragg glass show excellent
agreement.  A discussion of these findings is given in Sec.~III below.

Another important benefit of the macroscopic alignment of the nematic
director by the anisotropic gels is the pronounced enhancement in
signal-to-background in x-ray measurements relative to measurements on
smectics in isotropic gels.  Taking advantage of this enhancement, we
further provide in Sec.~IV a detailed study of the smectic correlations
at high temperature, which we analyze in terms of dynamic fluctuations
that grow on approaching the critical region of the destroyed N-SmA
transition.  This analysis shows that the correlations, as characterized
by effective critical exponents for the correlation lengths and
susceptibility, differ from those of pure 8CB even when the correlation
lengths are considerably smaller than the gel pore size, providing
evidence that the presence of quenched disorder alters the coupling
between nematic and smectic order and its influence over smectic
critical behavior.  When combined with similar results from smectics
confined to isotropic gels for effective critical exponents for the
specific heat and smectic order parameter~\cite{paperI,paperII,
Larochelle}, these findings provide a comprehensive picture of an
evolution in the N-SmA critical fluctuations toward conventional 3D XY
behavior with increasing quenched disorder.

\section{Sample Preparation and Characterization}

Pure 8CB undergoes an isotropic to nematic transition at $T_{NI}$ =
313.98 K and a N-SmA transition at $T_{NA}$ = 306.97 K~\cite{germano}.
Confinement of the liquid crystal to aligned aerosil gels was
accomplished through a procedure described previously~\cite{Liang}.
Type 300 hydrophilic aerosil (DeGussa Corp.)~was dried under vacuum at
393 K for 24 hours.  The dried powder along with appropriate quantities
of 8CB (Frinton Laboratories, Inc.)~was dissolved in high-purity
acetone, and the mixtures were sonicated for at least two hours.  The
solutions were then heated to 318 K to evaporate the solvent slowly.
After no visible trace of acetone remained, the samples were heated to
338 K under vacuum.  The resulting composites consisted of 8CB confined
to isotropic fractal aerosil gels like those of previous studies
~\cite{park,finotello-sil,paperI,paperII,Liang,zhou,Mertelj}.  To create
anisotropic gels, we placed each sample in a 2 Tesla magnetic field and
cycled the temperature between 308 K (nematic phase) and 318 K
(isotropic phase) at least 100 times.  Due to the magnetic anisotropy of
nematic 8CB, the director tends to align parallel to the magnetic field,
in competition with the random orientational fields created by the gel.
Due to the elasticity of the nematic and the compliance of the gel, this
competition results in restructuring of the gel to accommodate the
magnetic anisotropy.   As a result, the gels acquire a structure in
which the orientational fields are no longer random but on average
orient parallel to the aligning direction.  Since the gel continues to
have a random structure positionally, the positional fields that couple
to the smectic density wave remain random.  Samples were prepared in
this manner with aerosil densities ranging from $\rho_s=0.027$ g
sil/cm$^{3}$ 8CB,
which is just above the gelation threshold,  to
$\rho_s=0.10$ g sil/cm$^{3}$ 8CB, which is the upper limit above which
efforts to align the gels were ineffectual.

The smectic correlations that form in this anisotropic random
environment were studied through high-resolution x-ray scattering.  The
experiments were conducted at the X22A beam line of the National
Synchrotron Light Source.  The beam line is equipped  with a Ge(111)
monochromator to select a beam  of 10 keV x-rays.  The measurements were
performed in transmission geometry.  The beam size was approximately 1
mm $\times$ 1 mm, and the sample thickness was approximately 1.5 mm to
match the attenuation length of the 10 keV x-rays.  A triple-bounce
Si(111) channel-cut analyzer crystal was positioned between the sample
and a scintillation point detector to achieve high wave-vector
resolution.

To determine the degree of anisotropy in the orientational fields
coupling to the liquid crystal, we characterized the mosaic spread of
the smectic layer normal by ``rocking curve'' measurements through the
smectic scattering peak.  Figure~{\ref{mosaic}} shows mosaic scans for
$\rho_s$ = 0.027 and 0.10 g/cm$^3$ at T=298.1 K, several degrees below
$T_{NA}$.
\begin{figure}
\centering\includegraphics[scale=0.45]{liang_Fig1.eps}
\caption{Normalized scattering intensity of the smectic peak at fixed
wave vector magnitude ($q \approx 0.2$~\AA$^{-1}$) as a function of
sample orientation for 8CB confined by an aligned aerosil gel with
$\rho_s$ = 0.027 g/cm$^3$ (solid squares) and 0.10 g/cm$^3$ (open
circles and solid triangles) at 298.15 K.  The two scattering
intensities for  $\rho_s$ = 0.10 g/cm$^3$ correspond to measurements
before (open circles) and after (solid triangles) annealing the sample
in the isotropic phase of 8CB. }
\label{mosaic}
\end{figure}
The smectic scattering displays strong azimuthal anisotropy, indicating
a narrow distribution of smectic layer-normal orientations.  The
alignment is slightly better (the peak is narrower) for lower density
gels, consistent with the gels' increased ability to resist
restructuring with increasing density due to greater in mechanical
strength~\cite{paperII,8CBrheo}.  We note these measurements were
performed several weeks after removal of the magnetic field used to
align the gels; thus, the observed macroscopic alignment is a
consequence of the gel and not the external field.  As also shown in
Fig.~{\ref{mosaic}}, the quality of the nematic alignment displays
negligible change in response to temperature excursions into the
isotropic phase, demonstrating that the anisotropic gel structure is
stable against thermal fluctuations and sufficiently robust to re-align
the nematic director on subsequent cooling.  Indeed, samples are
observed to remain aligned after repeated heating into the isotropic
phase and after storage for several months.  Thus, the random
orientational fields of the isotropic gel have been converted into
fields with long-range order that align the nematic director
macroscopically.

\section{Smectic Correlations:  Evidence for an XY Bragg Glass}

Figure 2(a) displays the low-temperature x-ray scattering intensity for
$\rho_s$ = 0.027 g/cm$^3$ as a function of wave vector parallel to the
alignment direction ({\it i.e.}, the direction of the magnetic field
used to prepare the gel), $q_z$, and perpendicular to it,  $q_x$.  In
the alignment direction the intensity displays a pronounced peak
corresponding to the smectic scattering, while in the perpendicular
direction the intensity shows no evidence of smectic scattering,
consistent with the strong anisotropy implied by Fig.~1.  We ascribe the
scattering intensity along $q_x$ entirely to the gel structure and note
that an essentially identical background intensity contributes to the
scattering along $q_z$.  In order to isolate the smectic scattering from
this background, we subtract the intensity along $q_x$ from the
intensity along $q_z$.  This procedure assumes that the anisotropy in
the gel structure does not affect the scattering from the gel in the
wave-vector range of the smectic peak.  As described previously, small
angle scattering measurements support this assumption~\cite{Liang}.
Nevertheless, the observed smectic signal greatly exceeds this
background contribution, by a factor of more than a factor of $10^4$ in
Fig.~2(a), and this strong signal-to-background, which results from the
azimuthal focusing by the aligned orientational fields, enables the
detailed examination of the smectic correlations described below.
Figure 2(b) displays the results for the scattering intensity along
$q_z$ from Fig.~2(a) with the background subtracted.  Also in the figure
is the resolution function determined from the profile of the direct x-ray
beam.  The inset to Fig.~2(b) compares the scattering to the
resolution in the region of the peak.  The peak is clearly broader than
the resolution even for this lowest aerosil density at low temperature.
\begin{figure}
\centering\includegraphics[scale=0.45]{liang_Fig2.eps}
\caption{(a) X-ray scattering intensity for 8CB confined by an aligned
aerosil gel with $\rho_{S}=0.027$ g/cm$^{3}$ at 296.15 K as a function
of wave vector parallel to the gel's alignment direction, $q_z$
(circles) and perpendicular to this direction, $q_x$ (triangles).  (b)
Scattering intensity along $q_z$ with the intensity along $q_x$
subtracted to isolate the smectic scattering.  The solid line in (b) is
the instrumental resolution obtained from the incident beam profile.
The inset to (b) shows the peak region on an expanded scale.}
\label{peak_bg}
\end{figure}

As a first effort to characterize the smectic order, we consider a
correlation function based on the random-field model that has been used
previously to describe the short-range smectic correlations observed
under confinement in isotropic aerosil
gels~\cite{park,paperI,clegg8OCB,clegg8S5}.
Specifically, we model the smectic peak with the two-component line
shape
\begin{eqnarray}
    I({\bf q}) =
    \frac{\sigma_{1}}{1+(q_{\|}-
q_{0})^{2}\xi_{1\|}^{2}+q_{\bot}^{2}\xi_{1\bot}^{2}+c_{1}q_{\bot}^{4}\xi
_{1\bot}^{4}} \nonumber  \\
    +  \frac{a_{2}(\xi_{2\|}\xi_{2\bot}^{2})}{(1+(q_{\|}-
q_{0})^{2}\xi_{2\|}^{2}+q_{\bot}^{2}\xi_{2\bot}^{2}+
    c_2q_{\bot}^{4}\xi_{2\bot}^{4})^{2}}
\label{ocko_ocko2}
\end{eqnarray}
where $q_{\|}$ and $q_{\bot}$ are the wave vectors parallel and
perpendicular to the smectic layer normal, respectively, and $q_{0}$ is
the ordering wave vector.  The first term in $I(\bf{q}$) is an
anisotropic Lorentzian with fourth-order correction that describes
critical dynamic fluctuations on approaching the N-SmA transition in
pure liquid crystals.  $\sigma_1$ is the smectic susceptibility, and
$\xi_{1\|}$ and $\xi_{1\bot}$ are the correlation lengths of the
fluctuations in the directions parallel and perpendicular to the nematic
director, respectively.  The second term, which has a shape that is
proportional to the square of the thermal fluctuation term, describes
static short-range fluctuations due to the random fields, which are
characterized by the correlation lengths $\xi_{2\|}$ and $\xi_{2\bot}$.
Previous studies of smectics in isotropic aerosil gels have found that
the correlations display two temperature regimes.  At low temperature,
$a_2>0$, and the amplitude of the static fluctuation term rises from
zero with decreasing temperature.  At higher temperature, $a_2=0$, and
the scattering profile is similar to that of the nematic phase of pure
8CB, where pre-transitional smectic critical fluctuations
dominate~\cite{paperI,clegg8OCB,Larochelle}.

Figure~{\ref{highT}} shows the results of fits to Eq.~(\ref{ocko_ocko2})
with $a_2=0$ at two temperatures in this high-temperature regime for 8CB
confined by an aligned gel with $\rho_s = 0.10$ g/cm$^{3}$.
\begin{figure}
\centering\includegraphics[scale=0.45]{liang_Fig3.eps}
\caption{Background-subtracted scattering intensity of the smectic peak
for 8CB confined to an aligned aerosil gel with $\rho_s=0.10$ g/cm$^{3}$
at (a) 309 K and (b) 306 K.  The solid lines are the results of fits to
Eq.~(\ref{ocko_ocko2}) with $a_2 = 0$.}
\label{highT}
\end{figure}
To perform fits to Eq.~(\ref{ocko_ocko2}), we integrate numerically over
the distribution of layer normal orientations, as determined by rocking
curves like those shown in Fig.~\ref{mosaic}, and convolve with the
instrumental resolution.  In this analysis $\xi_{1\|}$ and $\xi_{1\bot}$
are treated as independent parameters, while the amplitude of the
fourth-order correction term, $c$, is treated as a function of
$\xi_{1\bot}$, with $c(\xi_{1\bot})$ set by the behavior in pure
8CB~\cite{ocko,J_theon,davidov}.  (Allowing $c$ to vary as an additional
free parameter leads to significant scatter in the fit parameters.)  As
Fig.~{\ref{highT}} illustrates, the dynamic term in
Eq.~(\ref{ocko_ocko2}) provides an excellent description of pre-
transitional smectic fluctuations in 8CB confined to aligned aerosil
gels at high temperatures.  This agreement allows us to study in detail
the pseudo-critical behavior of 8CB with anisotropic quenched disorder,
as described in Sec.~IV below.

Turning to low temperature, the dynamic fluctuation term in Eq.~(1)
alone cannot describe the measured lineshape.  As mentioned above,
previous analysis of the smectic correlations under confinement in
isotropic aerosil gels~\cite{park,paperI,clegg8OCB,clegg8S5} have
modeled the low-temperature scattering by including the contribution in
Eq.~(1) from static fluctuations ($a_2 >0$).   In most cases, this
analysis has assumed that $\xi_{2\|}=\xi_{1\|}$ and
$\xi_{2\bot}=\xi_{1\bot}$; that is, the correlation lengths in the
static and dynamic terms were assumed equal.  Typically, this approach
provided good agreement with the measured line shapes.  Indeed, in a
preliminary report on 8CB confined to aligned aerosil gels, we found
that Eq.~(\ref{ocko_ocko2}) with $\xi_{2\|}=\xi_{1\|}$ and
$\xi_{2\bot}=\xi_{1\bot}$ described the data accurately~\cite{Liang}.
However, this agreement does not necessarily indicate that the analysis
is capturing the correct physical picture.   As pointed out recently by
Larochelle {\it et al.}, the results of such analysis lead to trends in
the smectic susceptibility and correlation lengths that are inconsistent
with calorimetric studies of smectics confined to aerosil
gels~\cite{Larochelle}.   Calorimetry measurements on 8CB in isotropic
aerosil gels at low density ($\rho_{s} < 0.10$ g/cm$^{3}$) show a sharp
peak in the heat capacity, with power-law temperature dependence
resembling pre-transitional critical behavior extending over an extended
range of reduced temperature both above and below an effective
transition temperature T$^*$~\cite{zhou}.  This behavior would suggest
that  $\xi_{1\|}$, $\xi_{1\bot}$, and $\sigma_1$ should similarly decay
as a power law as a function of reduced temperature away from T$^*$.  As
discussed in Sec.~IV,  for T $>$ T$^*$ the smectic fluctuations in 8CB
confined to aligned aerosil gels indeed show a quasi-critical increase
toward T$^*$.  However,  analysis of the x-ray results at low
temperature using Eq.~(\ref{ocko_ocko2}) with $\xi_{2\|}=\xi_{1\|}$ and
$\xi_{2\bot}=\xi_{1\bot}$ leads to correlation length and susceptibility
values that remain large away from T$^*$.  For example,
$\xi_{\|}\approx$ 3000 \AA~at T$^*-$T = 9 K for 8CB confined to an
aligned gel with $\rho_{s}=0.10$ g/cm$^{3}$~\cite{Liang}, inconsistent
with pseudo-critical behavior.  Such large dynamic fluctuations
persisting to low temperature seem very unlikely.  However, if we
restrict the dynamic fluctuations to follow a more plausible temperature
dependence, we find that  Eq.~(1) cannot describe the x-ray lineshapes
for 8CB in aligned gels at low temperature.  Rather, as we explain
below, the lineshape predicted for the XY Bragg glass with an
appropriate cut-off for a finite nematic domain size can very accurately
describe the measured lineshapes for low densities of aligned aerosil.

To examine the situation more closely, we display in
Figs.~\ref{log_log}(a) and \ref{log_log}(b) log-log plots of the
scattering intensity versus $(q_z-q_0)$ at various temperatures for
$\rho_s = 0.042$ g/cm$^3$.  As described in Sec.~IV, the effective
transition temperature for $\rho_s = 0.042$ g/cm$^3$ is  T$^*$ = 305.0
K.  As seen in Fig.~\ref{log_log}(a), the intensities at temperatures
above T$^*$ overlap at large $(q_z-q_0)$.
\begin{figure}
\centering\includegraphics[scale=0.45]{liang_Fig4.eps}
\caption{Background-subtracted scattering intensity at various
temperatures as a function of the difference in wave vector from the
ordering wave vector, $q_0$, for  $\rho_s = 0.042$ g/cm$^3$.  (a)
intensities at several temperatures ranging from just below T$^*$ =
305.0 K to several degrees above T$^*$.  (b) intensities at two
temperatures, 300.1 K and 309.1 K, that are approximately the same
difference in temperature from T$^*$.  The dashed line in (b) is the
result of a fitting the intensity at 300.1 K in the peak region
($(q_z-q_0) < 10^{-3}$  \AA$^{-1}$) to the second term in
Eq.~(\ref{ocko_ocko2}) ($\sigma_1 = 0$) representing static short-range
order.}
\label{log_log}
\end{figure}
This collapse indicates that the intensities away from the peak share
the same wave-vector dependence, specifically that of the critical
fluctuation term in Eq.~(\ref{ocko_ocko2}), and further that the ratio
$\xi_{1\|}^2/\sigma_1$ is a constant independent of temperature
(implying the critical exponent $(2 - \eta) \approx 2$).  Similarly, for
the two temperatures just below T$^*$ shown in Fig.~\ref{log_log}(a),
303.9 K and 304.6 K, the intensities at large $(q_z-q_0)$ collapse onto
the data for T $>$ T$^*$.  This collapse indicates that critical
fluctuations continue to dominate the intensity at large $(q_z-q_0)$ at
temperatures near but below T$^*$.  This finding is not surprising since
one would expect to have large critical fluctuations in the vicinity of
a true critical point.  However, for lower temperature, the situation
becomes more complicated.  Plotted in Fig.~\ref{log_log}(b) is the
intensity at 300.1 K, approximately 4.9 K below T$^*$, along with the
intensity at 309.1 K,  approximately 4.1 K above T$^*$.  Not only does
the low-temperature curve fail to collapse onto the high-temperature
curve at large $(q_z-q_0)$, but it exhibits considerable excess
intensity at smaller $(q_z-q_0)$ that cannot be accounted for by either
term in Eq.~(\ref{ocko_ocko2}).  Specifically, the dashed line in
Fig.~\ref{log_log}(b) shows the result of fitting the low-temperature
intensity in the peak region to the static term of
Eq.~(\ref{ocko_ocko2}) alone ($\sigma_1 = 0$).  While the fit agrees
adequately with the measured intensity in the immediate vicinity of the
peak, it deviates significantly at larger $(q_z-q_0)$.  A comparison
with the high-temperature intensity demonstrates that the dynamic term
in Eq.~(\ref{ocko_ocko2}) cannot account for these deviations.   Since
the two intensities plotted in Fig.~\ref{log_log}(b) are for
temperatures that are approximately the same difference in temperature
from T$^*$, they correspond to approximately the same reduced
temperature.  Hence, the pre-transitional critical fluctuations at the
two temperatures should be similar (assuming the amplitude ratios for
the correlation lengths and susceptibility are of order one).  For
scattering from such critical fluctuations, a power law in the intensity
should be observed only for $( q_z-q_0) > 1/\xi_{1\|}$.  An inspection
of the line shape for 309.1 K indicates that for this reduced
temperature this asymptotic range is reached only for $(q_z-q_0) > 4
\times 10^{-2}$ \AA$^{-1}$.  The extension to lower $(q_z - q_0)$ of the
power-law behavior at 300.1 K thus indicates that the scattering
intensity is inconsistent with the small dynamic correlation lengths
expected at a temperature so far below T$^*$.  In essence, the
constraint used in the previous analysis~\cite{Liang} that
$\xi_{2\|}=\xi_{1\|}$ and $\xi_{2\bot}=\xi_{1\bot}$ led to artificially
large values of $\xi_{1\|}$ and $\xi_{1\bot}$ at low temperature that
fortuitously approximated the measured line shape but that on further
inspection cannot be justified as credible behavior for critical
fluctuations.

The extended power-law tails in the low-temperature scattering peak
instead suggest the possible presence of the XY Bragg glass phase.  As
mentioned above, the XY Bragg glass is ideally characterized by a power-
law divergent smectic scattering peak with a universal power-law
exponent.  As noted by the inset to Fig.~2(a), the measured scattering
peaks are appreciably broader than the instrumental resolution, which
precludes such power-law divergence extending to the lowest $(q_z -
q_0)$.  However, we argue that this discrepancy could be a consequence
of a large length scale cut-off introduced by the liquid crystal
ordering in the aligned gels.  Specifically, while the mosaic scans in
Fig.~1 indicate long-range nematic order, they also show an appreciable
spread in the smectic layer-normal orientations about the aligning
direction.  This spread indicates spatial variations in the smectic
layer normal that are likely set by the length scale characterizing the
nematic order.   In other words, the liquid crystal in the aligned gel
has finite-size nematic domains like in the isotropic
gels~\cite{bellini-sil-PRE}, the difference being that the domains are
not randomly oriented but rather have a distribution of orientations
clustered around the aligning direction.  Nevertheless, smectic order
cannot persist across two misaligned domains, leading directly to a cut-
off in the smectic correlations at low $(q_z - q_0)$.

Taking such an effect into account, we model the scattering peak at low
temperature with a form
\begin{eqnarray}
    I({\bf q}) = P({\bf q}) + H({\bf q})
\end{eqnarray}
where $P({\bf q})$ is the XY Bragg glass correlation function truncated
at small $(q_z - q_0)$, and  $H({\bf q})$ accounts for the finite-size
effect within a Gaussian approximation~\cite{sinha,kaganer}.  The XY
Bragg glass form is given by~\cite{toner_prl,saundersthesis}
\begin{equation}
    P({\bf q}) =
    \begin{cases}
    C((q_{\|}-q_0)^2 + \alpha q_{\bot}^2)^{-\delta/2}  \\
\text{\hspace{0.5cm} if $((q_{\|}-q_0)^2 + \alpha q_{\bot}^2) > 1/L$,}
    \\
CL^{\delta} \\  \text{\hspace{0.5cm} if $((q_{\|}-q_0)^2 + \alpha
q_{\bot}^2) < 1/L$.}
\end{cases}
\end{equation}
where $\delta$ is a universal, temperature-independent exponent
predicted to be $\delta = 2.45$~\cite{toner_prl,saundersthesis}, $C$
sets the overall amplitude, $\alpha$ is a non-universal constant that is
expected to be of order unity~\cite{toner_prl}, and $L$ is the size
scale of the nematic domains.  The finite-size correction has the
form~\cite{kaganer}
 \begin{equation}
    H({\bf q}) = Ae^{-L^2((q_{\|}-q_0)^2 + \alpha q_{\bot}^2)/4\pi}
\end{equation}
where the amplitude $A$ is related to $C$ such that at wave vectors
$((q_{\|}-q_0)^2 + \alpha q_{\bot}^2) < 1/L$ the Gaussian form of
$H({\bf q})$ dictates the line shape, while for larger wave vectors it
has negligible effect on the line shape~\cite{sinha}.  To perform fits
to Eq.~(2), we again integrate numerically over the distribution of
layer normal orientations, as determined by rocking curves like those
shown in Fig.~\ref{mosaic}, and convolve with the instrumental
resolution.  Figure 5 shows the result of a
\begin{figure}
\centering\includegraphics[scale=0.45]{liang_Fig5.eps}
\caption{Comparison between the background-subtracted scattering
intensity as a function of wave vector for $\rho_s = 0.027$ g/cm$^3$ at
296.1 K and the form predicted for an XY Bragg glass with a truncation
in the correlations at large length scales.  The circles are the
measured intensity, and the solid line is the result of a fit to
Eq.~(2).  The inset shows a comparison between the scattering intensity
and the fit result in the peak region on an expanded scale.  The XY
Bragg glass form agrees closely with the measured intensity over the
full range of wave vectors.}
\label{XYBG0p027}
\end{figure}
fit to Eq.~(2) for $\rho_s$ = 0.027 g/cm$^3$ at T = 296.1 K, the lowest
measurement temperature.  The figure displays the scattering intensity
over the full range of wave vectors, while the inset shows the peak
region on an expanded scale.  The agreement between the measured line
shape and the XY Bragg glass form is essentially perfect.  Good
agreement is similarly found for $\rho_s$ = 0.42 g/cm$^3$, as
illustrated by Fig.~6 which shows the result of a fit using Eq.~(2) to
the scattering intensity at T = 298.1 K for this aerosil density.  The
fits for both densities give $L \approx 1$ $\mu$m, in reasonable
agreement with a value expected based on the nematic correlation lengths
measured in isotropic aerosil gels~\cite{bellini-sil-PRE}.  The
anisotropy factor is found to be $\alpha \approx 0.15$ in the two cases.
For larger densities of aligned aerosil, the XY Bragg glass form is less
successful in describing the measured line shape, as illustrated by
Fig.~7 which shows the result of a fit using Eq.~(2) to the low-
temperature scattering intensity for $\rho_s$ = 0.10 g/cm$^3$.  We
interpret this discrepancy as an indication that the larger aerosil
densities impose positional disorder that is too strong for the XY Bragg
glass to be stable.

\begin{figure}
\centering\includegraphics[scale=0.45]{liang_Fig6.eps}
\caption{Comparison between the background-subtracted scattering
intensity as a function of wave vector for $\rho_s = 0.042$ g/cm$^3$ at
298.1 K and the form predicted for an XY Bragg glass with a truncation
in the correlations at large length scales.  The circles are the
measured intensity, and the solid line is the result of a fit to
Eq.~(2).  The inset shows a comparison between the scattering intensity
and the fit result in the peak region on an expanded scale.  The XY
Bragg glass form agrees closely with the measured intensity over the
full range of wave vectors.}
\label{XYBG0p042}
\end{figure}
\begin{figure}
\centering\includegraphics[scale=0.45]{liang_Fig7.eps}
\caption{Comparison between the background-subtracted scattering
intensity as a function of wave vector for $\rho_s = 0.10$ g/cm$^3$ at
298.1 K and the form predicted for an XY Bragg glass with a truncation
in the correlations at large length scales.  The circles are the
measured intensity, and the solid line is the result of a fit to
Eq.~(2).  Deviations between the XY Bragg glass form and the measured
intensity are apparent at large wave vectors.}
\label{XYBG0p10}
\end{figure}

For the lower aerosil densities, the close agreement with the XY Bragg
glass form extends over a range of temperatures below T$^*$.  However,
at temperatures sufficiently close to T$^*$, contributions to the
scattering from smectic critical fluctuations become appreciable.  These
contributions are apparent in the two temperatures slightly below T$^*$
included in Fig.~4(a) where both smectic critical fluctuations at  large
$(q_z-q_0)$ and additional contributions at smaller wave vector are
apparent.   Efforts to account for the contributions from dynamic
fluctuations in this temperature region by adding a term to Eq.~(2) are
successful in the sense that good agreement with the measured scattering
intensity can be achieved.  However, this analysis leads to large
uncertainties in the fit parameters; therefore, we will not discuss this
temperature region and will restrict our comparison to the XY Bragg
glass form to lower temperatures, where the dynamic fluctuations can be
safely neglected.  Figure 8 displays the values of the power-law
exponent $\delta$ extracted from fits over this low-temperature region
for $\rho_s$ = 0.027 and 0.042 g/cm$^3$.  The measured exponents for
both densities are remarkably close to the universal value predicted for
the XY Bragg glass, $\delta = 2.45$~\cite{toner_prl,saundersthesis},
shown by the dashed line in the figure.  We note that like the XY Bragg
glass phase, the smectic phase of pure liquid crystals possesses
quasi-long range order due to the Landau-Peierls instability and hence also
displays a power-law singular scattering peak.  However, the power-law
exponent along $q_{\|}$ for the smectic phase is always less than
2~\cite{kaganer,als-nielsen}, a value that is incompatible with the
measured line shapes for 8CB confined to aligned aerosil gels.  In
contrast, the close quantitative agreement between the exponent
predicted for the XY Bragg glass and the observed values lends strong
support to the conclusion that this topologically ordered phase forms in
8CB confined to aligned aerosil gels with low density.

\begin{figure}
\centering\includegraphics[scale=0.45]{liang_Fig8.eps}
\caption{Power-law exponent $\delta$ for the XY Bragg glass as a
function of temperature for 8CB confined to aligned aerosil gels with
densities $\rho_s = 0.027$ g/cm$^3$ (solid) and 0.042 g/cm$^3$ (open).
The dashed line is the universal value for the exponent, $\delta =
2.45$, predicted theoretically~\cite{toner_prl,saundersthesis}.}
\label{XYBGpower}
\end{figure}

Despite this excellent, quantitative agreement between the measured
scattering profiles for low densities of aerosil and the XY Bragg glass
form, we note that some caution is in order.  As described previously,
one can analyze the scattering intensity using Eq.~(1) with
$\xi_{2\|}=\xi_{1\|}$ and $\xi_{2\bot}=\xi_{1\bot}$.  (Although, the
agreement is not nearly as accurate as that of the XY Bragg glass form
nor does it cover as large a wave-vector range; see Fig.~5(c) in
Ref.~\cite{Liang}).  Further, the values that are obtained for
$\xi_{\|}$ and $\xi_{\bot}$ from fitting to Eq.~(1) are similar to those
found for 8CB confined to isotropic aerosil gels following the same
analysis~\cite{Liang}.  As we argue above, this analysis provides a
flawed physical picture; however, this coincidence in the correlation
lengths suggests that the smectic correlations that form in the aligned
gels and the isotropic gels are similar.  Since the XY Bragg glass phase
is not expected to be relevant to smectics confined to isotropic gels,
one might interpret this similarity as evidence against the XY Bragg
glass phase forming in the aligned gels.  Additional experimental work
on other smectic liquid crystals confined to aligned gels that test for
the presence of the XY Bragg glass phase would help in clarifying the
stability of this topologically ordered phase within the anisotropic
random environment created by the gel.

\section{High-Temperature Correlations:  Pseudo-critical Behavior}

As described above, the high-temperature scattering intensity of 8CB
confined to aligned aerosil gels is characterized by dynamic critical
fluctuations.  We interpret these fluctuations as the remnants of the
N-SmA critical point that is destroyed by the quenched disorder (and not
directly with the transition to the XY Bragg glass phase which
presumably has a significantly subtler signature in the x-ray scattering
than the observed robust peaks illustrated in Fig.~3).  Although the
N-SmA critical point is obtained strictly only in the presence of zero
quenched disorder, upon cooling in weak disorder the system in some
sense comes in close proximity to the critical point and should
therefore display critical smectic fluctuations.  Further, if the
disorder is sufficiently weak, the susceptibility and correlation
lengths charactering these fluctuations, while non-singular, should
display pseudo-critical behavior over an extended range of reduced
temperature.  This premise leads us to define the effective transition
temperature T$^*$ as the temperature at which these quantities would
diverge if their growth were not truncated:
\begin{eqnarray}
\label{ch4_q0L}
q_0 \xi_{1\|} \sim |t|^{ -\nu_{||}}\\
\label{ch4_q0L2}
q_0 \xi_{1\bot} \sim |t|^{ -\nu_\bot}\\
\label{ch4_gamma}
\sigma_1 \sim |t|^{ -\gamma}
\end{eqnarray}
where $t \equiv ($T$-$T$^*)/$T$^*$ is the reduced temperature, and
$\nu_{\|}$, $\nu_{\bot}$, and $\gamma$ are effective critical exponents
for $\xi_{1\|}$, $\xi_{1\bot}$, and $\sigma_1$, respectively.

If this assumption of truncated power-law divergences is valid, then the
three critical parameters should yield self-consistent values for T$^*$.
To test this assumption and to identify the correct value of T$^*$, we
fit the values of $\xi_{1\|}$, $\xi_{1\bot}$ and $\sigma_1$ to
Eqs.~(\ref{ch4_q0L})-(\ref{ch4_gamma}).  In these fits, only data at
high temperatures where the dynamic term in Eq.~(1) alone describes
accurately the measured line shapes were included.  As mentioned above,
at lower temperature (near but below T$^*$), additional contributions to
the scattering intensity, presumably from the static correlations of the
XY Bragg glass phase, appear.  Since efforts to separate these different
contributions lead to considerable uncertainties in the fit parameters,
we focus on the high temperature side of the critical region.  In the
fitting, the critical exponents were held fixed and T$^*$ was treated as
a free parameter.  These fits were repeated over a range of critical
exponents, and the quality of the fits, as determined from the $\chi^2$
values, was compared.  For all aerosil densities, the minima in $\chi^2$
for the three power-law relations, Eqs.~(\ref{ch4_q0L})-(\ref{ch4_gamma}),
occur at values of T$^*$ that are within 0.01 K of
each other.  We equate T$^*$ with the average of the three values
determined in this way for each aerosil density.  This value is listed
in Table~\ref{ch4_table_result}.  Comparing T$^*$ for different aerosil
densities, we note the value displays a non-monotonic dependence on
$\rho_s$ with a minimum near $\rho_s = 0.05$ g/cm$^3$, consistent with
the effective critical temperature determined with calorimetry for 8CB
confined to isotropic aerosil gels~\cite{germano}.
\begin{table}
\caption{Summary of effective critical exponents for 8CB confined to
aligned aerosil gels in comparison with pure 8CB and the 3D XY model.
Also included are the gel pore chords $l_0$~\cite{germano} and effective
transition temperatures T$^*$. }
\vspace{10pt}
\centering\begin{tabular}{|c||c|c|c|c|c|c|}
\hline
System&$l_0$ (\AA)&T$^*$ (K)&$\gamma$&$\nu_{\|}$&$\nu_{\bot}$&$\nu_{\|}
/ \nu_{\bot}$\\[3pt]
\hline
\hline
Pure 8CB&&306.97&1.26&0.67&0.51&1.314\\[3pt]
\hline
\multirow{2}{*}{0.027 g/cm$^3$}&\multirow{2}{*}{$\sim
3000$}&\multirow{2}{*}{305.96}&1.55&0.73&0.70&\multirow{2}{*}{1.05}\\[3pt]
&&&$\pm$0.05&$\pm$0.02&$\pm$0.02&\\[3pt]
\hline
\multirow{2}{*}{0.042 g/cm$^3$}&\multirow{2}{*}{$\sim
1500$}&\multirow{2}{*}{305.01}&1.54&0.74&0.65&\multirow{2}{*}{1.13}\\[3pt]
&&&$\pm$0.05&$\pm$0.03&$\pm$0.03&\\[3pt]
\hline
\multirow{2}{*}{0.071 g/cm$^3$}&\multirow{2}{*}{$\sim
900$}&\multirow{2}{*}{305.62}&1.56&0.75&0.66&\multirow{2}{*}{1.15}\\[3pt]
&&&$\pm$0.05&$\pm$0.02&$\pm$0.02&\\[3pt]
\hline
\multirow{2}{*}{0.10 g/cm$^3$}&\multirow{2}{*}{$\sim
600$}&\multirow{2}{*}{305.86}&1.53&0.73&0.65&\multirow{2}{*}{1.13}\\[3pt]
&&&$\pm$0.05&$\pm$0.02&$\pm$0.03&\\[3pt]
\hline
3D XY&&&1.32&0.67&0.67&1\\[3pt]
\hline
\end{tabular}
\label{ch4_table_result}
\end{table}

\begin{figure}
\centering\includegraphics[scale=0.22]{liang_Fig9.eps}
\caption{Dynamic correlation lengths $\xi_{1\|}$ (circles) and
$\xi_{1\bot}$ (triangles) as a function of reduced temperature for 8CB
confined to aligned aerosil gels with densities (a) $\rho_s = 0.027$
g/cm$^3$, (b) $\rho_s = 0.042$ g/cm$^3$, (c) $\rho_s = 0.071$ g/cm$^3$,
and (d) $\rho_s = 0.10$ g/cm$^3$.  The solid line are the results of
power-law fits.}
\label{ch4_corr_t}
\end{figure}
\begin{figure}
\centering\includegraphics[scale=0.22]{liang_Fig10.eps}
\caption{Smectic susceptibilty as a function of reduced temperature for
8CB confined to aligned aerosil gels of density for (a) $\rho_s = 0.027$
g/cm$^3$, (b) $\rho_s = 0.042$ g/cm$^3$, (c) $\rho_s = 0.071$ g/cm$^3$,
and (d) $\rho_s = 0.10$ g/cm$^3$.  The solid line are the results of
power-law fits.}
\label{ch4_s1_t}
\end{figure}
Figures \ref{ch4_corr_t} and \ref{ch4_s1_t} display log - log plots of
$\xi_{1\|}$, $\xi_{1\bot}$ and $\sigma_1$ as a function of reduced
temperature for T $>$ T$^*$ for various gel densities using the optimal
values of T$^*$.  The solid lines in the figures are the results of fits
to Eqs.~(\ref{ch4_q0L})-(\ref{ch4_gamma}), which demonstrate that the
temperature dependence is well described by power laws, further
reinforcing the idea of pseudo-critical behavior.
The effective critical exponents extracted from the fits are listed in
Table~\ref{ch4_table_result} along with the values for pure
8CB~\cite{ocko,J_theon,davidov}.  The values of $\nu_{\|}$,
$\nu_{\bot}$, and $\gamma$ for 8CB confined to aligned aerosil gels are
distinctly different from those of pure 8CB, indicating that the
quenched disorder introduced by the gel not only affects the
low-temperature smectic order but also modifies the pre-transitional
critical fluctuations.  At sufficiently high temperature the correlation
lengths are small compared to the mean pore chord $l_0$ of the
gels~\cite{germano}, which is also listed in
Table~\ref{ch4_table_result}.
Hence, the disorder caused by the gels should have little direct effect
on the smectic fluctuations well above T$^*$.  In the simplest picture
of the N-SmA transition, the formation of the smectic density wave
breaks 3D XY symmetry, and thus the critical behavior of pure liquid
crystals could be expected to match that of the 3D XY model.  However,
the observed critical behavior of pure 8CB and other smectic liquid
crystals typically deviates from that of the 3D XY model.  These
deviations are illustrated by the difference in critical exponent values
for pure 8CB and the 3D XY model listed in Table~\ref{ch4_table_result}.
The precise nature of these deviations, whose source likely involves
couplings between the smectic order parameter and the nematic order, has
been a long-standing problem.
As described above, when a smectic liquid crystal is confined to an
aligned aerosil gel, it experiences not only positional disorder that
couples to the smectic density wave but also anisotropic orientational
fields that couple to the nematic order,
thereby modifying the nematic behavior.  We therefore conclude that
differences in the critical fluctuations between pure 8CB and 8CB
confined to aerosil gels originate from the coupling of nematic order to
the gel and its indirect influence on the smectic critical behavior.

\begin{figure}
\centering\includegraphics[scale=0.45]{liang_Fig11.eps}
\caption{Critical exponents (a) $\nu_{\|}$, (b) $\nu_{\bot}$, and (c)
$\gamma$ for different smectic liquid crystals as a function of McMillan
ratio, $R_M \equiv \frac{T_{NA}}{T_{NI}}$.  The values for various pure
liquid crystals, shown by circles, are taken from~\protect\cite{nounesis}.  The
values for pure 8CB are shown by the solid circles.  Also included are
the values of the effective critical exponents for 8CB confined to
aligned aerosil gels with densities $\rho_s = 0.027$ g/cm$^3$,
(triangle), $\rho_s = 0.042$ g/cm$^3$ (diamond), $\rho_s = 0.071$
g/cm$^3$ (upside-down triangle), and $\rho_s = 0.10$ g/cm$^3$ (square),
which are assigned effective McMillan ratios using
Eq.~(\ref{ch4_Rm_eff}).  The solid lines mark the exponent values for
the 3D XY model, and the dashed lines are guides to the eye.}
\label{ch4_Rm}
\end{figure}

As an illustration, compare the ratio $\nu_{\|} / \nu_{\bot}$ for
varying aerosil densities with the ratio for pure 8CB listed in
Table~\ref{ch4_table_result}.  For the 3D XY model, the ratio is one due
to the isotropic scaling of correlations.  However, for pure 8CB the
scalings are highly anisotropic ($\nu_{\|} / \nu_{\bot}$ = 1.314),
consistent with behavior seen in various other smectic liquid
crystals~\cite{nounesis}.  Patton and Andereck have advanced a theory
that this anisotropic scaling results from coupling between nematic
director fluctuations and the smectic order parameter~\cite{andereck,
patton}.
For 8CB confined to aligned aerosil gels, the ratio
$\nu_{\|}/\nu_{\bot}$ shows much weaker scaling anisotropy than in pure
8CB.  One interpretation for this decreased scaling anisotropy is that
pinning of the nematic director by the anisotropic orientational fields
suppresses long-wavelength nematic fluctuations, thus weakening their
influence over the smectic critical behavior.

While the decrease in $\nu_{\|}/\nu_{\bot}$ for 8CB confined to aligned
aerosil gels compared with $\nu_{\|}/\nu_{\bot}$ for pure 8CB indicates
qualitatively that the quenched disorder weakens nematic-smectic
coupling, this observation would be made stronger with a quantitative
measure of this weakening.  In pure liquid crystals, the strength of the
nematic-smectic coupling can be crudely parameterized by the McMillan
ratio
\begin{equation}
R_M \equiv \frac{T_{NA}}{T_{NI}}
\end {equation}
specifying the temperature range of the nematic phase.  Large $R_M$
indicates a short nematic range, which typically implies the nematic
order is far from saturated at the N-SmA transition.  Hence, for large
$R_M$ the nematic susceptibility can be expected to be large, and
concomitantly the order parameter coupling can be expected to be strong.
In a comprehensive survey of smectic critical behavior in pure liquid
crystals, Garland and Nounesis found that the critical exponents
$\alpha$, $\gamma$, $\nu_{\|}$, and $\nu_{\bot}$ obtained from
calorimetry and x-ray scattering studies displayed complex but
systematic trends as a function of $R_M$~\cite{nounesis}.  Figures
\ref{ch4_Rm}(a)-\ref{ch4_Rm}(c) display the values of the critical
exponents $\nu_{\|}$, $\nu_{\bot}$, and $\gamma$ of various smectic
liquid crystals as a function of $R_M$, as originally assembled by
Garland and Nounesis.
Liquid crystals with small $R_M$ generally have critical exponents that
approach the 3D XY values; however, the values of the exponents do not
change monotonically with decreasing $R_M$.  The critical exponents for
pure 8CB ($R_M$ = 0.977) are shown by the solid circles in the figures.
Also in Figs.~\ref{ch4_Rm}(a)-\ref{ch4_Rm}(c) are the effective critical
exponents for 8CB confined to aligned aerosil gels, which have been
placed on the figures by assigning the smectics with quenched disorder
an effective McMillan ratio,
\begin{equation}
R_M^{eff} = 0.977 - 0.72 \rho_s
\label{ch4_Rm_eff}
\end{equation}
As the figures illustrate, this mapping between disorder strength, as
parameterized by aerosil density, and nematic-smectic coupling, as
parameterized by McMillan ratio, places the effective critical exponents
for 8CB confined to aligned aerosil densities roughly in line with
trends of pure liquid crystals of varying $R_M$.  We note a very similar
linear mapping of aerosil density to effective McMillan ratio was
introduced previously for 8CB and 4O.8 confined to isotropic aerosil
gels~\cite{paperI,Larochelle}.
In these cases, the mapping was shown to collapse successfully effective
heat capacity and order parameter exponents, $\alpha$ and $\beta$, for
various aerosil densities onto the trends of pure liquid crystals.  The
linear coefficient that optimized the mapping for the smectics confined
to isotropic aerosil gels was smaller than that in
Eq.~(\ref{ch4_Rm_eff}), 0.47 as opposed to 0.72, suggesting that aligned
aerosil gels are more effective than isotropic gels in suppressing
nematic-smectic order parameter coupling.  Nevertheless, these linear
mappings provide a quantitative measure of how the presence of the
quenched disorder influences the smectic critical behavior.
The results in Figs.~\ref{ch4_Rm}(a)-\ref{ch4_Rm}(c) thus extend the
notion of an effective McMillan ratio to the effective critical
exponents $\nu_{\|}$, $\nu_{\bot}$, and $\gamma$, making comprehensive
the analogy between disorder strength and $R_M^{eff}$ for describing the
behavior of the pre-transitional critical fluctuations of smectic
confined to aerosil gels.  Further theoretical efforts to understand the
effects of quenched disorder could hence be a fruitful avenue for
unraveling the outstanding mysteries surrounding the critical behavior
of pure smectics.

\vspace{1 cm}
\noindent
{\bf Acknowledgements:}
We gratefully acknowledge C. Garland, G. Iannacchione, B. Ocko, and L.
Radzihovsky for helpful discussions.  Funding was provided by the NSF
under Grant No.~DMR-0134377.  Use of the National Synchrotron Light
Source, Brookhaven National Laboratory, was supported by the U. S.
Department of Energy, Office of Science, Office of Basic Energy
Sciences, under Contract No.~DE-AC02-98CH10886.

redpajama_set_name: RedPajamaArXiv


British Literature refers to literature associated with the United Kingdom along with that of Isles of Man and Channel Islands. For purposes of focused study, it has been divided into Middle Ages, Elizabethan period, Restoration era, Romantic period, Victorian era and the Modern period. Although literature of earlier times exists, Geoffrey Chaucer, the 14th century poet is said to be the first most important exponent of British Literature. The present work Studies in British Literature covers the representative writers right from Geoffrey Chaucer to Julian Barnes. All the great works of the great writers are represented here. So one can find articles on writers like Chaucer, Spenser, Marlowe, Donne, Jonson, Shakespeare, Bacon, Milton, Dryden, Fielding, Johnson, Blake, Wordsworth, Scott, Coleridge, Shelley, Keats, Tennyson, Browning, Brontë, Ruskin, George Eliot, Dickens, Hardy, Conrad, Hopkins, Shaw, Kipling, Yeats, Synge, T. S. Eliot, Woolf, Joyce, Lawrence, Beckett and Barnes. References have been given to several others in the text. All this is an interesting and useful endeavour. The articles are critical, comprehensive and updated. The book provides a glimpse of British Literature under one cover. It will ably serve the needs of students, teachers and researchers of English Literature, particularly British Literature.
Mallikarjun Patil, M.A., Ph.D from Karnataka University, is a novelist, short-story writer, translator and critic. He is a distinguished academician, being a Reader in English, Karnataka University, Dharwad. He has written numerous articles and two works on Thomas Hardy, apart from Studies in American Literature and British Literature. His novel When the Ground Shakes Beneath has been translated into Kannada, Punjabi and Hindi. His A Don in the Jungle is a political novel on the forest brigand of yesteryears, Veerappan. He has translated Bajranga Korde's English work Anna Bhau Sathe into Kannada for Sahitya Akademi, New Delhi. In Shakespeare's England is a travel account of his education at Oxford and his visit to various places in England.


The first major political event of the 19th century in South America was the recognition by the great powers of independence for the states which made up the Spanish Empire in Latin America. This happened at the end of 1824 and it ushered in the first major economic event of the century for Latin America – the 1825 mining boom and bust. Up to his ears in this latter event was none other than Benjamin Disraeli, destined in due course to become one of Britain's greatest Prime Ministers when the country was at the peak of its powers.


They just opened a new restaurant near my job and everyone keeps raving about it and from the crowd you could tell it has to be good because we have A lOT of restaurants in this area and everyone has seemed to flock to this place.
This is Pita Pan's second location, the original is in Astoria Queens which is known for it's Greek food and you know how much I love me some Greek, OPA! Pita Pan's tag line is "Fresh Fast Tasty", I am a fan of all three things so I decided to give them a shot.
Today was Protein Day so I could not try what I really wanted which was a Pita Pan Gyro so I reluctantly decided to get a salad; they have a great selection of Gourmet Organic salads. I chose the Mandarin Salad; baby mustard greens with sliced almonds, mandarins, raisins, and honey vinaigrette. They give you the option to add protein for an additional charge, so you know I had to get Gyro Meat lol. For me, the best way to tell if a salad is good is by choosing to leave the dressing off AND I DID! This salad was full of so much flavor that I didn't even see the point of the dressing. Another thing I liked was that it was not HUGE; sometimes a salad can be overwhelming but if you are starving, they do give you the option to double it for an extra charge.
Besides a great selection of salads, sandwiches, paninis etc; they also have a variety of smoothies. I decided to try the Berry Smooth Smoothie which is anti-oxident berries, banana, mint, and fresh low fat yogurt. This was perfect for my afternoon slump; it woke my bum up lol. It was not heavy but instead very refreshing on this 90 degree day.
I already told my sister that she has to meet me one day so that we could have dinner at the restaurant.
Remind me again what you do for protein day...do you just do one per week?
Sounds great--I'll check it out next time I'm there!
I try to stay away from "Bad" carbs on the two days before my weigh in. This is something that my nutritionist would make me do when I was trying to lose weight and it seemed to work. She said it was to "shock" my system.
I am so missing my oatmeal!


Synopsis: Wes is a typical 3rd grader. Wes goes to school. Wes enjoys sports. We is jealous... What? Jealous!? See how the seemingly innocent observations of this young boy turn into a biter jealousy towards his neighbor, classmate and all around nemesis, Reynold. Is Reynold the selfish, know-it-all, show-off Wes imagines him to be? More importantly, once confronted, will Wes be able to swallow his pride and make peace with his jealous side? Or will his jealousy eat him alive?


text:
Q: When using AWS SDK, the subsequent .then() in Promise didn't wait for previous .then() to finish I am too naive in the JS world. Why is my Javascript Promise not working as expected? I thought console.log("update configs"); won't be executed until console.log("checking bucket"); is completed. Thanks in advance for any help.
Note: the 'checking bucket' function continuous check S3 bucket exists every few seconds until the S3 bucket is created.
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    WebsiteConfiguration: {
      ErrorDocument: {
        Key: "error.html"
      },
      IndexDocument: {
        Suffix: "index.html"
      }
    }
  };
  s3.putBucketWebsite(params2, function(err, data) {
    if (err) console.log(err, err.stack); // an error occurred
    else console.log(data); // successful
  });
});

A: Thanks everyone for the feedback and hints. I found I can retrieve promise object directly from AWS SDK function. Here is the revised code that is working now.
// Create S3 service object
var s3 = new AWS.S3({
  apiVersion: '2006-03-01'
});

var params = {
  Bucket: bucketName,
  ACL: "public-read"
};

var promiseObject = s3.createBucket(params, function(err, data) {
  console.log("creating bucket");
  if (err) {
    console.log(err, err.stack); // an error occurred
  } else {
    console.log(data); // successful
  }
}).promise();  // <=== THIS LINE SAVED MY DAY !!

promiseObject.then(function(data) {
  console.log("checking bucket");
  var params = {
    Bucket: bucketName
  };
  s3.waitFor('bucketExists', params, function(err, data) {
    if (err) console.log(err, err.stack); // an error occurred
    else     console.log("bucket exist");           // successful response
  });
})
.then(function(data) {
  console.log("update configs");
  var params2 = {
    Bucket: bucketName,
    ContentMD5: "",
    WebsiteConfiguration: {
      ErrorDocument: {
        Key: "error.html"
      },
      IndexDocument: {
        Suffix: "index.html"
      }
    }
  };
  s3.putBucketWebsite(params2, function(err, data) {
    if (err) console.log(err, err.stack); // an error occurred
    else console.log(data); // successful
  });
})

redpajama_set_name: RedPajamaStackExchange


The Lincoln MKZ is a luxury sedan that is well received by those who seek top technology features and comfort while driving. Technology features are important when making an investment in a vehicle.
The Lincoln MKZ has SYNC 3 which offers voice-activated commands while you drive. This works with making phone calls, navigation, and more. You can keep your eyes on the road while your voice-commands do all of the work!
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Organic cotton mix tee with a vintage wash and a bold, block colour pattern, the Modern T-shirt has got style nailed. With O'Neill Hyperdry and wicking, it's got keeping you looking and feeling dry and fresh no matter what you're up to covered too. An all round winner.


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text:
Dirty Water Now
NFL Draft filled with surprise picks
Casey Grace Murtagh
The 2018 NFL Draft was filled with surprises, plenty of booing, and two Heisman trophy winners.
Before we get into the nitty-gritty details of the first round, let's delve into the Patriots Draft decisions Thursday night. With the 23rd pick, the Patriots scooped up Isaiah Wynn. Wynn is a tackle out of Georgia– he's a great run blocker and has wonderful footwork. This kid is an explosive player and is able to slide out of a tackle in 'emergency situations.' He is surely a starter and has experience with both the guard and tackle positions. With the 31st overall pick, the Patriots selected a second Georgia man– Sony Michel. Michel is a skilled Running Back who has the ability to weave between the defensive line and can truly outrun most of the guys on the field. He's been compared to Kamara in his run game ability– and will surely fill a similar offensive position that Dion once held. The Patriots have a specific role for each back in their offense and Michel will find his role and run with it– literally.
With the No. 1 pick in the draft, the Browns took Baker Mayfield, a QB out of Oklahoma. New England fans are used to hearing the phrase, "he has a chip on his shoulder"– with respect to Tom Brady's fiercely competitive spirit, and quite frankly I'm sick of hearing that about Mayfield. This kid was a walk-on Heisman Trophy winner and had everyone talking about him for the past four months. Just because Nike passed up on him and he got into some College Drama, does not a chip\make. Sure, he has reason to prove people wrong– but Tom Brady rose like a Phoenix from the ashes of obscurity to become the best QB of all time (now that is a chip). Regardless, this kid can throw the ball and is a highly accurate playmaker. The question of whether Mayfield or Taylor will start for the Browns is now up for debate.
The second pick went to the Giants and they chose Saquon Barkley out of Penn. Saquon is an unbelievably dynamic Running back, and he will be yet another offensive weapon for the Giants to call on next season. Who knows, maybe with OBJ and Saquon on the field, Eli will be able to catch some W's next season– but I doubt it. However, Eli is a "better QB when the run game is freed up," and clearly Gettleman felt that Eli still has some miles in his tank and they didn't need to draft his heir apparent just yet.
With the third pick, the Jets took Sam Darnold from USC. For most of the week, Darnold was expected to go number one overall, and you could see the sadness in his when he spoke with Deion Sanders last night. When Deion asked if he was thrown off by Mayfield going first, he replied– "when I didn't (get the call from the Browns) it was onto New York" and "I'm just going to do my job." Perhaps the Browns were worried about his ability to keep the ball secure when the pocket is loose– which he has displayed some issues with throughout his college career. Either way, Darnold is a great player who is very accurate on the run.
The Browns were back on the clock at No. 4, selecting Denzel Ward. Ward is a Defensive Back from Ohio State, who had a 4.32 forty yard dash in the Combine. He was able to secure 37 tackles and 2 interceptions in the 2017 season. I personally figured the Browns would go with Darnold at number one and Saquon at number four. However, Dorsey saw the problem in their defense and took the best corner in the draft to fix that issue. Ward is a starter from day one, and he will be a great addition to their team.
The Broncos secured NC State's Defensive End, Bradley Chubb with the fifth pick of the night. Chubb was the 2017 ACC Defensive Player of the year, with a whopping 26 career sacks. He truly impacts the run game and is a very physical player. When Deion asked Chubb what got him to the draft, he replied– "on the field, it is my motor… and off the field, it is my family."
Next up, the Colts picked Quenton Nelson, a dominant offensive guard from Notre Dame. If luckis on Indianapolis' side, the Colts will have Andrew back and they'll need a guy like Nelson to keep him safe on the field. Nelson was a favorite for the Broncos, but I personally had him going to the Colts in my mock draft– as he is ready to go from the start and the Colts desperately need a dominant guy on their line of scrimmage.
The Bills traded up for the Buccaneer's pick and clenched Josh Allen at No. 7. The Wyoming QB, fell into some controversy the morning of the draft after some (aptly timed) tweets were revealed to the media. Allen's tweets were racist and disgraceful in nature, however, it did not seem to affect his draft stock, as teams do a deep dive on each player months in advance and they likely already knew about his gross high school tweets. The Bills just signed a two year and ten million dollar deal with McCarron, so Allen has some time to work out his kinks (both on and off the field). If I were Brandon Beane, I would have gone with Rosen because of his highly academic approach to the game and his skilled throwing mechanics, but Allen has time to learn and work on his accuracy. Positively, he has the ability to throw the ball like an arrow and is an overall athletic guy.
With the eighth pick of the draft, the Bears took Roquan Smith. Smith is a Linebacker out of Georgia who was a favorite for the top ten overall. He will be a great fit for the Bears' Defense and is a very dynamic player. The 49ers snagged Mike McGlinchey in the ninth pick of the evening. McGlinchey, an offensive tackle out of Notre Dame, is there to protect San Fran's golden boy– Jimmy G. He is a coachable player and at 6'8'' and 309 lbs, he is the brick wall the 49ers need to keep their investment secure.
The Cardinals traded with the Raiders for the tenth pick of the draft, and they (finally) selected Josh Rosen out of UCLA. Rosen is a QB with a wildly accurate arm and has a very technical approach to throwing the ball. He plays the game from an academic and strategic point of view. There have been questions about his coachability, however, his High School coach clarified that he simply wants to know the reasons why coaches ask certain things of him, so he can better understand the game and how he fits within it. Rosen is a natural passer and had 26 touchdowns and 10 interceptions in 2017.
With the 11th pick in the draft, the Dolphins selected Minkah Fitzpatrick. Fitzpatrick is a Defensive Back from Alabama, and he will be a good fit in Miami. He is great on man to man coverage and is dominate enough to cover a tight end. He had nine interceptions in his career and four of them were returned for touchdowns. With the twelfth pick of the night, the Buccaneers' selected the Defensive Tackle out of Washington– Vita Vea. This was a surprising decision because they had recently signed a group of Defensive players in free agency. Vea is nearly 350 lbs, but he plays with vigor and immense power– he will do well in Tampa Bay.
With the 13th pick of the night, Da'Ron Payne was chosen by the Redskins. Payne is an assertive Defensive Tackle out of Alabama. He will do well in Washington as their Defensive line is filled with players from the Alabama system. Payne, in particular, makes it very hard for an offense to run the ball– as seen in his 102 career tackles at 'Bama. With the fourteenth pick of the night, the Saints traded with Green Bay, selecting Marcus Davenport. Davenport is a Defensive End from UTSA. He is an edge rusher and will do very well in New Orleans. The Raiders were next with the fifteenth pick, selecting Kolton Miller from UCLA. A formidable Offensive Tackle, like Miller, is surely needed in Oakland.
The Bills traded up with the Ravens for the 16th pick of the evening, selecting Tremaine Edmunds out of Virginia Tech. Edmunds is a nineteen-year-old Linebacker, whose "rare size and skill set give him a sub package versatility," and he is great at tracking and sacking QBs.
With the 17th pick, the Chargers went with Derwin James– a Defensive Back from Florida State. James is a large athlete but he is much smoother than you would expect from a bigger safety. Similar to Minkah Fitzpatrick, he is the type of guy who can cover tight ends on man to man coverage. Next, after a trade with the Seahawks, Green Bay picked up Jaire Alexander– a Defensive Back out of Louisville. Alexander is a starting corner, despite missing six games last year. He is skilled with tracking the football in the air and "adds value in the punt return game."
With the 19th pick of the draft, the Cowboys selected Linebacker Leighton Vander Esch, from Boise State. He has suffered from neck issues in the past but remains a great overall athlete. He's the type of player who really understands and predicts routes– and will be an asset in Dallas. The Lions were next with the 20th pick of the night, choosing Frank Ragnow– a Center out of Arkansas. A few mock drafts had Ragnow going to the Pats, so it's interesting that he ended up landing with Matty P's Lions. Next up, another starting Center was chosen by the Bengals– Billy Price out of Ohio State.
The Titans traded with the Ravens for the 22nd pick of the night, selecting Rashaan Evans. Evans is a Linebacker from Alabama and had fifteen sacks in his career. He will be a starter, and fit in well with the Titans defense. As mentioned previously, with the 23rd pick of the night, the Patriots selected Isaiah Wynn from Georgia. With the following pick, the Carolina Panthers selected DJ Moore, a Wide Receiver from Maryland. Moore has 'big ups' and can snatch the ball from high in the air. He will join the likes of Funchess and Cam Newton in an unbelievable lineup of offensive players.
With the 25th pick of the first night, the Ravens selected Hayden Hurst, a tight end from South Carolina. I'm personally shocked they went with Hayden Hurst before Lamar Jackson. I guess they figured no other team desperately needed a QB at that point in the draft, and Jackson would still be there later on (via trade), while Hurst may not be. Hurst, a former baseball player, is a natural athlete and can "line up in the slot and win matchups against smaller nickels and safeties."
The Falcons selected Calvin Ridley, a Wide Receiver from Alabama, at No. 26. Ridley is extremely fast an will fit in very well with the likes of; Devonta Freeman, Tevin Coleman, and Julio Jones. Seattle chooses Rashaad Penny, a Running Back out of San Diego State, as the 27th pick of the night. Penny is a "premiere kick returner" and was previously offensive and special teams player of the year. The Steelers follow with Terrell Edmunds, a Safety from Virginia Tech. Edmunds secured 59 tackles and 2 interceptions in his career. He was announced by Ryan Shazier and his fiance — and OH MAN, I had tears in my eyes watching Shazier walk up to the podium, that man is unstoppable. Sending love and positivity to the Shazier family.
The Jaguars followed with Taven Bryan, a Defensive Tackle from Florida. Bryan was a one-year starter, but had an impressive combine workout with "measurables similar to Gerald McCoy." The Vikings then selected Mike Hughes, a Defensive Back from the University of Central Florida. This CB transferred from JUCO after the 2016 season and is a dependable player that will fit in well with the Vikings defense. With the 31st pick of the draft, the Patriots selected, the aforementioned — Sony Michel.
Lastly, with the 32nd overall pick in the 2018 NFL Draft, the Ravens traded with the Eagles to select Lamar Jackson. Jackson, a QB out of Louisville, was the Heisman Trophy winner in 2016. He had 27 touchdowns and 10 interceptions in 2017, as well as 1,601 rush yards. He has incredible skill and speed and was slept on in this draft. He is comparable too and/or better than many of the top QBs in this draft class and should have been taken at an earlier pick. It did not seem to phase Jackson in the end, as he kept repeating that "(he) was just happy to be a Raven" and that "they are going to get a Super Bowl out of (him)."
Previous articleOn a Mission: 2018 Red Sox Charge Up Slow Start for MLB
Next articlePatriots get A+ grade from Sports Illustrated on 2018 NFL Draft
Casey Grace Murtagh is an actress, represented by WSM Talent. She has a passion for writing as well. Casey recently created and starred in the film "Exit 7" which is produced by her own production company— 17 Grace Films. She can be seen in multiple commercials from; Build-A-Bear Workshop, to the New Hampshire Lottery, to Friendly's! She has also worked on Internal shoots for TJX and Care Academy. Casey has been in a number of independent films and television series' including; "Testing: The Series" by Angel wood Pictures, "Rose Force" by Chip Perro, "Inevitable War" by Director Thomas Bo, "The Making of Dark Harbor" by Matt Melia and Thomas Barbo, and MANY more! She has starred in many plays and musicals, and went to Walnut Hill School for the Arts for Writing & Publishing. She was President of "Ready Set Punchline", the premiere Stand-Up Comedy Troupe at Boston College. She is trained in Meisner acting from Boston College, where she graduated in Spring 2017 with a degree in Theatre.
Tweets from https://twitter.com/DWSportsBoston/lists/patriots-updates Follow @DWSportsBoston Tweet to @DWSportsBoston
New On Dirty Water Sports
Thomas Domol - January 24, 2020
Don't look now. Or perhaps, don't look at all. Seemingly out of nowhere, Boston's venerable sports teams find themselves in a torrid state of upheaval....
Red Sox January 15, 2020
Alex and the asterisk

redpajama_set_name: RedPajamaCommonCrawl


Where did it break on the technium? I lost a fish when it snapped at a leader knot, the only knot to use on technium is Palomar which is miles stronger.. I went over to cm90 and havnt had a break or anything in 2 years in 15lb. I have respooled twice and will be respooling again soon.. love it, before that I tried virtually every line on the market!
I've used both Technium black which I've found to be very good and very low stretch and ESP synchro xt which is both and the one I prefer.
Might be worth looking at the spiderwire offerings, they do both EZ and hybred mono, which I think they now sell as ultimate mono.
Can I ask what are your reasons for specifically wanting low stretch mono?
Pro Gold, if you can get hold of it.
Birmingham Angling center has some I'm told.
Never tried Shimano Technium or Gardner GT, but apparently they're low stretch.
Touchdown has lower strecth than CM90.
Mad really as that�s one line I�d trust anywhere. Feel like me reels going to snap trying to retrieve it at times.
Recently had trans khaki 20lb go on me on what I thought was a real small snag. Was impressed until that happened. That night it came off and technium went back on.
GT-HD is very good indeed. I hate Technium now, the first time I lost the Thames record, it was that, which it snapped like cotton with over 100 yards out. I used to love it before that. I saw a new line to me recently, and I was super impressed with it. Low diameter, low stretch, 3.3mm rated at 18lb. I watched my friend break a 30lb braid link, when straight rodding it to retrieve a snagged rig on a flooded river. It's very strong, very limp, great colour. Casts a dream. I was visually impressed, he loves it.
�9.99 a spool, it's called Katran Synapse.
Agreed. Technium Black has very little stretch.


Angelina Jolie was moved to tears for the second time in a week, after speaking on CNN about her visit to Afghanistan as a UN Goodwill ambassador.
As the actress recollected her time in the war-torn country, she concentrated her story on a 15-year-old orphan who was paralysed by a gunshot wound.
'He had this really remarkable, unbreakable spirit, a spirit beyond anything I can imagine.
'He had lost everything and he was just so full of laughter and kindness.
Earlier last week the A-lister showed her vulnerable side again, in an emotional address at a conference to mark World Refugee Day.
Following the Changeling actress's $1million donation with Brad Pitt to aid refugees in Pakistan, Jolie described her charity work as something that has deeply affected her life.
'The refugees I have met and spent time with have profoundly changed my life. The eight-year-old girl who saved her brother taught me what it was like to be brave.


text:
Stem cell technology to cure spinal cordv injuries introduced in KSA
By admin March 6, 2014 Stem Cell Treatment
The Sultan bin Abdulaziz Humanitarian City (SAHC) announced Tuesday its intention to take stem cell transplantation to new heights by using the method to cure spinal cord injuries. The announcement was made by Prince Khaled bin Sultan, chairman of the Sultan bin Abdulaziz Al-Saud Foundation (SAAF), during the international spinal cord injury conference 2014, which kicked off at the SAHC headquarters on Tuesday. The theme of the conference, which ends on Thursday, is Toward a Better Quality of Life. The conference, first introduced in Australia and New Zealand, is being held for the first time in the Middle East. The technology, in collaboration with the US-based University of Miami, will revolutionize the scope of paralysis surgery in the Kingdom, making it a leader in the field. An accord on collaboration between the SAHC and the Miami Project to Cure Paralysis (MPCP), the first center in the US to receive approval from the supervisory board of the Food and Drug Administration for stem cell therapy, was also signed. Prince Khaled said that the transfer of this technology comes amid efforts to help families cope with the life-changing effects of spinal cord injuries. Prince Khaled said many people between the ages of 16 and 22 suffer such debilitating injuries. The MPCP works on several research and rehabilitation programs in the field of spinal cord and traumatic brain injury, he said. The transfer of this technology to the SAHC will make Saudi Arabia one of the first countries in the region to benefit from the revolutionary treatment of spinal cord injury through stem cell research. SAHC Executive President Abdullah Zarah said the conference would address the latest findings of modern science in the field of spinal cord injury and stem cell transplantation. Around 1,500 Saudis are afflicted with spinal cord injuries every year due to accidents. Rizman Hamid, a senior neurology lecturer at University College London, told Arab News that being afflicted with this type of injury is a lifelong condition. Such critical ailments require follow-up, with radiological investigation to optimize bladder function. Patients should undergo regular investigation as a means of detecting potential problems in the bladder, which can lead to kidney damage, he said. He added that another major problem resulting from spinal cord injuries, especially among women, is urinary incontinence, which has severe and adverse effects on patients. This condition can be cured through a procedure known as the transobtruator tape. This is a minimally invasive procedure that has good long-term results, he said. Firas Sirhan, director of the Center of Excellence for Telehealth and Assisted Living (CETAL) at Buckinghamshire New University in Middlesex, England, said that the use of technology and health care practice is becoming more visible in the treatment and management of spinal cord injuries. Telehealth represents an entirely new way of managing injury that does not easily fit within existing health care frameworks, he said. The use of the telehealth model has contributed to empowering patients to become more involved in the self-management of their condition. Telehealth could be an effective tool that contributes to allowing health care professionals, as well as patients, to recognize and identify any changes in medical conditions. He added that the center can assist in developing packages that combine tested clinical service models with assessed technology to present workable telehealth services based on specific needs.
regenerative medicine – How Stem Cells Fight Aging – Adult Stem Cells – Video
First Road Map of Human Sex-Cell Development


text:
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$starWarsObj->selectAllStarWarsSets();
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redpajama_set_name: RedPajamaGithub


text:
Putin and the World order: What lies ahead?
Russian President Vladimir Putin (Sputnik via Xinhua/IANS)
By Shivaji Sengupta
The 15th, is the Ides of March as the Romans used to say. It is the day Julius Caesar was assassinated by Roman senators, driven desperate by Caesar's dictator-like attitude and rule.
Last night, in an absorbing discussion between the Indian TV journalist, Karan Thapar, and CNN's Fareed Zakaria, the question was asked: is there any way Vladimir Putin can be stopped by his own government, his own lieutenants? Can he be deposed? According to Zakaria, no. Not even the Russian army can enter Putin's mansion. He has his own Praetorian guards, a Roman term for a unit that served as personal body guards and intelligence agents for Roman emperors. Caesar had one; as did Saddam Hussain of Iraq. Putin has been building himself up for twenty-two years, to where he is today. Invincible.
Now, after nearly three weeks of war with Ukraine, he has become rigid to the extent he is almost unrecognizable to Western journalists who used to know him. Twenty years ago, he used to be a self-effacing, rational man of few words. His actions were measured, well thought out. Now, according to these very same journalists, he has become aloof, remote, not trusting of almost anyone. Having committed himself to war, and not being able to make it short, swift and decisive, having tasted blood, he is no longer satisfied with Ukraine not joining NATO, its promise to be neutral, its willingness to continue to negotiate some form of autonomy for Donetsk and Luhans. Now Putin wants more. He wants an official surrender, a demilitarized Ukraine, and he wants a regime change. If Putin has his way, Zelensky can no longer be Ukraine's president.
These are impossible conditions to accept for any self-respecting nation; especially Ukraine which has been in stiff opposition to Putin's Russia since the annexation of Crimea. The people of Ukraine have been steadily moving toward Western Europe, valuing the so-called individual freedom and its attendant lifestyle. They will never agree to accept the Russian way, being ruled by a dictator as they see Putin, and oligarchs. Putin, in power for the last twenty-two years, has become unmovable, both as a dictator and in his mind set. So where do we go from here? This man has already issued two warnings that Russia might use nuclear weapons in this war. Is he serious?
As I see it, this war can develop in four different ways. I will start with the second worst-case scenario. (The worst-case being nuclear war.)
The gloomiest prediction – for now – is for the present situation to continue, Ukraine's people resisting bravely, dying by the hundreds and injured by the thousands. Putin will try to grab the whole of Ukraine which will probably take a month more. However, as many journalists and war experts predict, the official fall of Ukraine is the easy part. The country will not surrender, will not demilitarize. Zelinsky will not go unless he is captured or killed. The people will resist, fight, conduct guerilla warfare – for the Russians, it will be Afghanistan in the 1980s all over again. Russia will lose thousands upon thousands of soldiers. The war will be costly. Add to that the long-term effects of the sanctions, and Russia will be an economic wreck. Vladimir Putin might himself lose popular support. Meanwhile, the NATO countries will continue to be on the sidelines, helping Ukraine with money and military. Joe Biden will watch most of his predictions slowly coming true. The worse Russians are off, the more Biden will gain in popularity at home provided Covid continues to subside, he can control the run-away inflation, and get the infrastructure bill passed by Congress, bringing jobs and putting money into people's pockets.
A second scenario would be for both Ukraine and Russia to realize that this war, if it ends with Ukraine's surrender, will benefit neither. Ukraine will be decimated, its leader, Vlodymir Zelensky deposed, and the country will be under Russia. For Russia, on the other hand, the trouble would just be beginning: a long drawn-out protracted war in Ukraine, with many Russian sympathizers wanting their soldiers back home, and the country bankrupt. Given such threatening situations both Zelensky and Putin might declare a face-saving cease fire. If that happens, Zelensky will be a hero in many parts of the world. Biden will gain at home politically. Putin will be further disgraced in the west. People will say his strategy of waiting out Putin worked.
A third scenario could be the European nations, slowly getting weary of the effects of the war in their continent, might secretly try to discourage Zelensky to continue the resistance and agree on a cease fire. Putin might compromise on surrender, no longer push for Ukraine's demilitarization and be willing to accept Ukraine giving in writing that it would not join NATO, and be prepared to give some measure of autonomy to Donetsk and Luhansk.
A final scenario is China playing a major role in the cease fire. We have been hearing about the China-Russia friendship, and China's abstaining from voting to condemn Russia in the United Nations General Assembly along with thirty-five other countries (including the entire subcontinent). Currently, it is propping up the Russian economy by buying its oil, ignoring the sanctions. Moreover, they have already been exporting to Russia articles of everyday use. However, what we do not much read about in America is that the Chinese are not too happy with the way Putin is bullishly going ahead with the war with a sovereign nation, thus defying a foundational principle in China's foreign policy. Besides, as the war and the sanctions continue, China's economic relationships with major Western European countries can be jeopardized. If there is one thing the Chinese understand, it is money. Mess with their money, and you run the risk of being bypassed by them. Putin might heed China because of Russia's heavy dependency on it. It all depends on what sort of compromise Xi Jin Ping can work out with Ukraine and Russia. If China can broker a deal with the two nations, it will gain instant popularity in the world. Just as likely, America's image as world leader will take a hit, despite Biden being the principal architect of the sanctions on Russia and Putin. We should remember that even if China were able to broker a cease fire, it couldn't happen without the sanctions.
Whatever its outcome, the Russia-Ukraine war is likely to change a lot of things. Mindful of Russia's invincibility because of its nuclear weapons superiority, other countries will be adamant about possessing nuclear weapons. Ukraine will want to get back theirs and Iran will be a handful.
John Mearsheimer of the University of Chicago, has observed that the world could be in great danger of a nuclear war between NATO and The United States, and Russia. Yes, Russia is to be blamed for starting the war, and bringing to a point where no one can predict how it will end. But why this war was started in the first place has a lot to do with Western Europe and the U.S. cajoling Ukraine further and further away from Putin's Russia, instead of encouraging it to stay neutral. Even if America succeeds in preventing an outright Russian victory against Ukraine, Ukraine, already severely damaged, may be decimated forever by this war: its people abandoned, maimed and killed; its economy tanked, Kyiv becoming a ghost town, an Indian journalist has observed, quoting W.H. Auden:
In the nightmare of the dark
All the dogs of Europe bark,
And the living nations wait,
Each sequestered in its hate;
Intellectual disgrace
Stares from every human face…
This war, and all the intellectual discussions thereof, continues unabated. Meanwhile people are dying, by the thousands.
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Welcome to my blog about Young Onset Parkinson's Disease (YOPD).
I was diagnosed with Parkinson's Disease on 20th November 2017. I am 44 year old man, married to a fantastic wife and have a gorgeous 5 year old son.
Young Onset Parkinson's Disease gradually revealed itself over the course of 2017, luckily for me the actual process from first referral to a neurologist to confirmed diagnosis by a movement disorder specialist took 3 months.
'A new normal' is explained in my first blog post.
I am attempting to record my progression and PD characteristics to hopefully help others & add to the data being recorded in blogs like these. If it could be harnessed I am sure it would be very useful in all sorts of ways.
The prognosis of Young Onset Parkinson's Disease and subtypes of PD are areas which interest me, as does the neuroscience of what happens in my and others brains.
I will evolve this blog over the coming months. For now I wish whoever reads this well & if you have YOPD please comment on you're experience.


text:
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  'use strict';

  angular.module('app.markinglist', []);
})();


text:
Home Breaking André Poggenburgs finish: Good for the AfD. Unfortunately
André Poggenburgs finish: Good for the AfD. Unfortunately
A herbaceous flower that only lives a year – that is the Symbol of the new party of André Poggenburg. The Ex-AfD-country party leader and former parliamentary leader in Saxony-Anhalt has recently left the AfD. The blue cornflower, Centaurea cyanus, is a provocation: it was the Symbol of the Austrian national socialists, as these were banned in 1933.
For Poggenburg this is not unusual. Through regular Affronts to the Public's attention to him, certainly, his last wish "of the citizens of our national community a healthy, peaceful and Patriotic 2019".
For the AfD but Poggenburgs outlet a luck. Until Monday, the right-wing populists to sit together on the Europe Congress. There are many offers on his exit: "It is good that he is gone," said AfD party leader Alexander Gauland. Poggenburg got rather annoyed. You don't see any competition for their own party. The AfD of the new party, you can look forward to even more relaxed – you will not be important.
Poggenburg is the AfD uncomfortable
The name validly published looks different, of course. "The departure of the German patriots – Central Germany" has he called the party with the cornflower. You would get the success, writes the name validly published on Facebook.
That will probably not be the case, is instrumental in Poggenburg, He has left the AfD, because he no longer feels supported by her. Not too long ago, Poggenburg was regarded as a Confidant of the Thuringian countryside, the heads of Björn Höcke, and a prominent representative of the so-called "wing" on the right side of the AfD. Although the name validly published trying to explain, he is content, but it is quite obvious that it's a lot about personal injuries and dislocations. For voters, this is very rarely a reason to change the party.
A Chance of success of a party such as the "riser" is actually only Höcke itself. The don't want to leave the AfD appears to be – probably because it is unlikely to achieve without the moderate wing similar choice.
The AfD uses a number of Poggenburg. You can now specify that she wanted to get rid of the radical forces. This is nonsense, you have to run only once more the statements of the leaders of the AfD. It Gauland, spoke of the Hitler dictatorship as a "bird-shit of the story," Alice ryegrass swore was up in a Bundestag speech allegedly "alimentierte knife men", and also the wing to Höcke remains of the party.
how do the voters of the "new beginnings"?
in Spite of the failures of the top staff is the fact that Many of the AfD-voters are not neo-Nazis. You are unhappy with the refugee policy of the German Chancellor, Angela Merkel, and perhaps also with the social policy. But they are not neo-Nazis. This is another reason for apparent lack of success of "new beginnings".
Would not be the potential for a neo-Nazi party in Germany is really so high, was because the NPD so miserably, as it does currently. It is fragmented, to the right of her are two more small parties, "The third way" and "right now".
Where, then, should come from the voters of "awakening"? To the right of the AfD, but not in the NPD? In spite of the incompatibility clause of the AfD and the NPD, there are between the two parties, the content and rhetorical Overlap. There's not much space for a new party.
the three state Parliament elections in Thuringia, Brandenburg and Saxony to begin and the name validly published. Hard to imagine that the "awakening" in Thuringia for the Höcke-AfD could become a danger. Andreas Kalbitz, the country head of the Brandenburg AfD, is also part of the wing, ten years ago, he attended a Pentecostal camp, the now-banned right-wing "homeland-faithful German youth".
Really, only the Saxon AfD needs to worry. Here is the "break-in", with its Connections to Pegida could achieve a success. The AfD would get a couple of percentage points less, could the Saxon CDU.
LKR, the blue party and the break-in
In the long term, but it is highly unlikely that the "awakening" will play in the public perception. Two prominent Ex-AfDler of the party, party founder Bernd Lucke and Ex-party leader Frauke Petry turned away:. Hatch had to go, because the right-wing forces in the party were stronger Petry, because they were stronger.
the two men founded new parties. The "Liberal-Conservative reformers" of the hatch have around 1000 members, the "blue party" from Petry had members in Saxony last August, just 87, your citizen movement ", The blue turning to" something over 500, she said the "Sächsische Zeitung".
The AfD could both damage. It is likely that it will be the right fork of Poggenburg. The AfD itself is right enough.
the name validly published will continue to call "Germany for the Germans", and with statements like "growths on the German people's body" in the reporting pages of the Newspapers heave. Success you will not be able to call it.
by the Way: According to the name validly published he had not chosen the Symbol of the cornflower, because Austrian national socialists used, but because it is a sign of home and closeness to nature, to Patriotism and the struggle for freedom.
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