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text:
Department for Afroamerican and African Studies pres.
DAAS Diasporic Dialogues: "Theatre, Womanist Knowledge-Making and Violence in Jamaica: Witnessing A Vigil for Roxie."
Nicosia Shakes (Africana Studies The College of Wooster)
In this talk, Nicosia Shakes analyzes a 2015 performance of the play, A Vigil for Roxie, co-created by Jamaican theatre artists, Carol Lawes, Eugene Williams, Honor Ford-Smith and Amba Chevannes. As part of the Memory, Urban Violence and Performance Project founded by Ford-Smith, Vigil for Roxie draws on the memorial practices of working-class Black Jamaican women who have lost loved ones to gang and state violence over the past three decades. Shakes utilizes a womanist paradigm to explore the racial, economic and gendered dimensions of memory, healing and justice as depicted in Vigil. By representing experiences of gang and state violence through the bodies and voices of Black women, Vigil challenges mainstream male-centered understandings of violence while creating a holistic vision of social justice involving the community, nation and wider region of the Americas.
Nicosia Shakes is Assistant Professor in the Department of Africana Studies at The College of Wooster. Her book manuscript, Gender, Race and Performance Space: Women's Activism in Jamaican and South African Theatre, won the National Women's Studies Association/University of Illinois Press First Book Prize in 2017, and is under contract with UIP.
Contact Event Organizers: Department for Afroamerican and African Studies
Map Haven Hall - 4701 (DAAS Conference Room)
Fri, Apr 5 2019 4:00pm - 6:00pm

redpajama_set_name: RedPajamaCommonCrawl


text:
Economy »
Knowledge Economy »
What is the importance of patents?
A patent is a property right granted by the government to an inventor, giving them the sole right to manufacture, use, or sell an invention for a period of time. The rate of patents is an important indicator of investment into research and development, technological change, and regional labor force qualities. Patents are used as an indicator on their own, or can be grouped with other indicators to gauge a region's overall innovative capacity. On their own, patents suggest creativity and the application of knowledge, and form a useful indicator comparable across geographies. By providing new or improved products and services the creation of knowledge contributes directly to the region's competitiveness and improvement of living standards. This indicator speaks to the improvement of productive capacities and services, which in turn is an important measure of competitiveness, and improvement in living standards.
What is measured?
Patents are measured as the number of patents issued, along with relative measures such as Arizona's percent share of southern Border States, U.S. totals.
How competitive is Arizona?
To gauge Arizona's relative competitiveness in the region, the trend in the rate of patents per capita is compared with other U.S. border states. Data are provided on an annual bases with indices of percentage change between observed periods.
The table on this page displays the number of utility patents per 1 million residents for southern U.S. Border States on an annual basis. Data are updated following release by the U.S. Patent and Trademark Office. Click on any title to graph that series, and export. Or, click "download" at the base of the table to download the dataset, or customize based on a specified range.
Unavailable - Number of Patents IssuedPer Million, State PopulationAnnual
U.S. Patent and Trademark Office (USPTO) . Patents reported are the number of utility patents (patents for the invention of a new mechanism, technological process or device) granted by the U.S. Patent and Trademark Office to residents of a particular state. Origin of the patent is determined by the residence of the first-named inventor.
U.S. Census Bureau, Population Division (USCB) . Population data for 2000 through 2009 is derived via Intercensal Estimation using the April 1, 2000 and April 1, 2010 census data. Population data from 2010 forward is measured as the number of people on July 1 of each year as estimated by the USCB Population Estimates Program (PEP). Current data is for Vintage 2015. Vintage is the term used by the U.S. Census Bureau to denote an entire time series; because the current vintage applies the most up-to-date input data and estimating methodologies to all years since the previous census the current vintage supersedes all previous data series.
Photo of business graph courtesy of Shutterstock.
Photo of scientist in lab coat courtesy of Shutterstock.
Photo of electric wheel grinding on steel in factory courtesy of Shutterstock.


text:
\section{Introduction}

For a long time, solar dynamo theory was in an advantageous situation compared
to planetary dynamo theory. In the Sun, dynamo generated magnetic fields can be
directly measured on the boundary of the turbulent, conducting domain where
they are generated; and the timescales of their variations are short enough for
direct observational follow-up. Solar observations also put many constraints on
the motions in the convective zone, significantly restricting the otherwise
very wide range of admissible mean field dynamo models.

In the past 15 years, however, planetary dynamo theorists have turned the table.
Realistic numerical simulations of the complete geodynamo have been made
possible by the rapid increase in the available computing power. While the
parameter range for which such simulations are feasible is still far from
realistic, extrapolations based on the available results have allowed important
inferences on the behaviour of planetary dynamos
(\citen{Christensen:plan.dynamo.solar}, \citen{Petrovay:solar.planet.dynamos}).

In the light of these developments, learning from solar dynamo theory may have
lost much of its former appeal to geophysicists, especially as it has become
increasingly clear that the two classes of dynamos operate in fundamentally
different modes, under very different conditions. Yet, keeping track with
advance in the other field may not be without profit for either area. Even
though the overall mechanisms may be very different, there may be many elements
of each system where intriguing parallels exist.

A comprehensive review of solar dynamo theory is beyond the scope of the present
article; for this, we refer the reader to papers by \cite{Petrovay:SOLSPA},
\cite{Charbonneau:livingreview}, \cite{Solanki+:RPP} and
\cite{Jones+:dynamo.rev}.

Aside from reproducing the dipole dominance and other morphological traits
of the geomagnetic field,
two aspects of the geodynamo that are critical for judging the merits of its
models are field reversals and long-term variations: whether or not a model can
produce such effects in a way qualitatively, and if possible quantitatively
similar to the geological record, has become a testbed for geodynamo
simulations. It may thus be of special interest to review our current
understanding of the analogues of these phenomena in the Sun. This is the
purpose of the present paper.

In Section~2 we outline what solar observations suggest about the causes of
reversals, i.e.\ the Babcock--Leighton mechanism. Two questions naturally
arising from this discussion are given further attention in Sections 3 and 4.
Section~5 briefly discusses some issues related to long-term variations of solar
activity, while Section~6 concludes the paper, pointing out some interesting
parallel phenomena in solar and planetary dynamos.

\section{Reversals and global magnetism on the Sun}

Information about large scale flows in the solar convective envelope can place
important constraints on dynamo models. In the solar photosphere (the thin layer
where most of the visible radiation originates) these flows can be directly
detected by the tracking of individual features and by the Doppler effect. But
in recent decades {\it helioseismology} (a technique analoguous to terrestrial
seismology, see review by \citen{Howe:LRSP}) has also shed light on subsurface
flows. In particular, the internal {\it differential rotation} pattern is now
known in much of the solar interior. It is characterized by a marked latitudinal
differential rotation (faster equator, slower poles) throughout the convective
envelope, while the radiative interior rotates like a rigid body. A thin
transitional layer known as the {\it tachocline} separates the two regions. {\it
Meridional circulation,} on the other hand is currently only known in the
outermost part of the convective zone where it is directed from the equator
towards the poles. A return flow is obviously expected in deeper layers but this
has not yet been detected.

The invention of the magnetograph in 1959 marked a breakthrough in the study of
solar magnetism. The output of this instrument, the magnetogram, is basically an
intensity-coded map of the circular polarization over the solar disk. Circular
polarization in turn is due to the Zeeman effect and, in a rather wide range (up
to field strengths of $\sim 1\,$kG), it scales linearly with the line of sight
component of the magnetic field strength. Apart from the saturation at kilogauss
fields, then, a magnetogram is essentially a map of the line of sight magnetic
field strength over the solar disk in the photosphere. Conventionally, fields
with northern polarity are shown in white, while fields with southern polarity
are shown in black.

\begin{figure}
\begin{center}
\epsfig{figure=mgram_bigbear, width=0.9\textwidth}
\end{center}
\caption{A solar magnetogram: a map of the line of sight magnetic field strength
over the solar disk. Fields with northern (southern) polarity are shown in white
(black).
\hfill\copyright Big Bear Observatory}
\end{figure}

Figure~1 shows an arbitrarily chosen magnetogram as an example. It is
immediately clear that the strongest magnetic concentrations, called {\it
active regions} (AR), occur in bipolar pairs. Filtergrams and non-optical
images showing the higher layers of the solar atmosphere confirm that these
pairs mark the footpoints of large magnetic loops protruding from the Sun's
interior into its atmosphere. In white light images these active regions appear
as dark {\it sunspot groups} and bright, filamentary {\it facular areas.} The
lifetime of spots, facul{\ae} and active regions is finite: turbulent motions in
the solar photosphere ultimately lead to their dispersal over a period not
exceeding a few weeks.

In addition to the strong active regions, Fig.~1 also displays some weaker and
more extended magnetic concentrations, also in bipolar pairs (e.g.\ a bit upper
left from the center). These features, only seen in magnetograms, are the
remains of decayed active regions, the bipolar pair of flux concentrations
being dispersed over an ever wider area of the solar surface. Ultimately, all
that is left is a pair of {\it unipolar areas} ---areas of quiet sun where
the ubiquitous small-scale background magnetic field is dominated by one
polarity or another.

\begin{figure}
\begin{center}
\epsfig{figure=halepol_eng, width=0.7\textwidth}
\end{center}
\caption{Sketch illustrating Hale's polarity rules in the growing phase of two
consecutive 11-year cycles (left and right, respectively)}
\end{figure}

We can see that the bipolar magnetic pairs are mostly oriented in the E-W
direction, (with a slight tilt, to be discussed below). In the northern
hemisphere, the N polarity patches lie to the west of their S polarity pairs,
while in the southern hemisphere the situation is opposite. In the image, the
direction of solar rotation is left to right and the rotational axis is
approximately vertical and in the plane of the sky. ``Western patches'' are
therefore referred to as the {\it preceding polarity} part of the active region,
while their eastern pairs are the {\it following polarity} part. The rule we
have just noticed then says that, at any given instant of time, preceding
polarities of solar active regions are uniform over one hemisphere and opposite
between the two hemispheres. Measurements performed during the course of
several solar cycles show that, in any given hemisphere, the preceding polarity
remains unchanged during the course of each 11-year solar cycle, while it
alternates between cycles. This regularity, known as {\it Hale's polarity
rules,} is schematically illustrated in Fig.~2. This implies that the
true period of solar activity is 22 years in the magnetic sense.

This sketch also shows one further regularity in the polarities. The weak
large-scale magnetic field is usually opposite near the two rotational poles,
and these polarities also alternate with a 22 year periodicity. However, the
phase of this 22 year cycle is offset by about $\pi/2$ from the active region
cycle, i.e. magnetic pole reversal does not occur in solar minimum. Instead,
reversals typically take place 1--2 years after solar maximum, right in the
middle of a cycle (as cycle profiles are asymmetric).

\begin{figure}
\epsfig{figure=synopmap, width=\textheight, angle=90}
\caption{A synoptic magnetic map of the Sun \hfill{\small\copyright NSO}}
\end{figure}

Systematic magnetograph studies coupled with pioneering work on magnetic flux
transport shed light on the apparent origin of the field reversal already in the
1960s (\citen{Babcock}, \citen{Leighton:diffusion}). For a better understanding
of how this so-called Babcock--Leighton mechanism works, consider a {\it
synoptic magnetic map} like the one shown in Fig.~3. Such synoptic maps are
essentially constructed by taking a narrow vertical strip from the center of
each daily magnetogram (i.e. along the central meridian) and sticking them
together from left to right, in a time sequence covering one synodic solar
rotation. In this way we arrive at a ``quasi-instantaneous'' (in as much as
$P_{\mathrm{rot}}\ll 11$ years) magnetic map of the full solar surface. In
Fig.~3 we see further ample evidence of Hale's polarity rules, but what is more
interesting is the systematic deviation of the orientation of bipolar pairs
from the E--W direction. It is clear that following polarity parts of active
regions are systematically closer to the poles than their preceding polarity
counterparts, and the tilt angle of the AR axis increases with heliographic
latitude ---a phenomenon known as {\it Joy's law.}

\begin{figure}
\epsfig{figure=butfly_mg, width=\textwidth}
\caption{The magnetic butterfly diagram: longitudinally averaged
magnetic field strength as a function of latitude and time, based on Mt.~Wilson
Observatory data. The grayscale goes from -2 G (black) to +2 G (white).}
\end{figure}

As a consequence of Joy's law, upon the decay of active regions the resulting
following polarity unipolar areas will be predominantly found on the poleward
side of the active latitude belt. Now recall from Fig.~2 that in the early phase
of a solar cycle, the following polarity in a given hemisphere is opposite to
the polarity of the corresponding pole. As the decay of ever newer active
regions replenishes its magnetic flux, this following polarity belt, located
poleward of the active latitudes, will expand towards the pole, a process
greatly helped by turbulent magnetic diffusion and by the advection of the large
scale magnetic fields due to the Sun's large scale meridional circulation.
Ultimately, shortly after solar maximum, the preceding polarity patches around
the two poles shrink to oblivion, and following polarity takes over: a reversal
has taken place.

The process can be followed in the ``magnetic butterfly diagram'' shown in
Fig.~4. Each pixel in this plot represents the intensity-coded value of the
longitudinally averaged magnetic field strength at the given heliographic
latitude and time. The butterfly wing shaped areas of intense magnetic activity
at low latitudes represent the activity belts, migrating from medium latitudes
towards the equator during the course of each solar cycle. The poleward drift
apparent at high latitudes, in turn, corresponds to the poleward expansion of
following polarity areas discussed above. It is clear that the reversal of the
predominant magnetic polarity near the poles is due to this poleward drift,
confirming the Babcock--Leighton scenario.

However compellingly the observations argue for such a scenario, two open
questions remain.

1. What is the origin of the latitude-dependent tilt of active regions (Joy's
law)?\\
In the Babcock--Leighton scenario this tilt is clearly the ultimate cause of
flux reversals. $\alpha\omega$ dynamo models rather naturally lead to
predominantly toroidal, i.e.\ E--W oriented magnetic fields, so the tilt
compared to this prevalent direction is likely to develop during the process of
{\it magnetic flux emergence} from deeper layers into the atmosphere. This leads
us to discuss flux emergence models in Section~3.

2. Do magnetic flux redistribution processes seen at the surface indeed play an
important role in the dynamo, or are they just manifestations of similar,
more robust processes taking place deep within the Sun?

The nice consistent cause-and-effect chain involved in the Babcock--Leighton
scenario (AR tilt $+$ AR decay $\rightarrow$ $f$-polarity unipolar belt;
$f$-polarity belt $+$ flux transport $\rightarrow$ reversal) seems to argue
strongly for the first option. However, as we will see in Section~4 below,
keeping the surface physically decoupled from the deeper layers is not easy,
and such models invariably need to rely on some rather dubious physical
assumptions. Thus, while parametric models of the first type can be fine-tuned
to show impressive agreement with observations, their physical foundations
remain shaky. Conversely, models based on more sound and plausible physical
assumptions have had limited success in reproducing the details of
observations. This constitutes the main dichotomy in current (mainstream) solar
dynamo thinking, to be discussed in Section~4.

\begin{figure}
\epsfig{figure=floopsketch, width=0.9\textwidth}
\caption{Sketch of the probable subsurface magnetic structure of an active
region. $B_P=(2\mu_0 P)^{1/2}$ is the pressure equipartition field strength, $P$
being the thermal gas pressure outside the flux tube. $B_e$
is the turbulent equipartition field strength as defined in the text.}
\end{figure}

\section {Flux emergence}

The current mainstream picture of the subsurface magnetic structure of solar
active regions is sketched in Fig.~5. The observed distribution and proper
motion patterns of sunspots and other magnetic elements in active regions are
strongly suggestive of the so-called {\it magnetic tree scenario:} the cluster
of smaller and larger magnetic flux tubes that manifest themselves as sunspots,
facular points etc. in the photospheric layers of an active region are all
connected in the deeper layers in a tree-like structure. The characteristic
sizes of unipolar patches in a typical bipolar active region suggest that the
trunk of this magnetic tree starts to fragment into branches at a relatively
shallow depth, on the order of $\sim 10\,$\% of the thickness of the convective
zone. During the emergence of the tree  structure, magnetic elements,
corresponding to mesh points of the tree branches with the surface, naturally
seem to converge into larger elements, ultimately forming large sunspots. This
is just how sunspots are observed to be formed.

The natural initial configuration for such a magnetic loop, fragmented in its
upper reaches, is a strong toroidal (i.e.\ horizontal and E--W oriented)
magnetic flux bundle lying below the surface.  The high field strength is a
requirement imposed by the strict adherence to Hale's polarity rules. Indeed,
there are almost no exceptions to these rules among large active regions, so
the drag force associated with the vigorous turbulent  convective flows in the
solar envelope must be small compared to other forces acting on the tube, in
particular the curvature force. As the total magnetic flux of the tube must be
similar to the flux of large active regions ($\sim 10^{22}\,$Mx), from this
condition it can be estimated that the field strength must significantly exceed
the equipartition field $B_e$  where the magnetic and turbulent pressures are
equal ($B_e^2/2\mu_o=\rho \langle v^2\rangle/2$).
It follows that $B\ga 10^4\,$G ($\sim 1\,$T)
in the deep convective zone.

It is however well known (\citen{Parker:buoy.prob}) that such strong horizontal
magnetic flux tubes cannot be stably stored in a superadiabatic
or neutrally stable environment.
The magnetic pressure implies that the gas pressure inside the flux tube is
reduced in order to maintain pressure equilibrium with the environment. The
associated decrease in density of the compressible plasma makes the flux tube
magnetically buoyant.
In order for such tubes to remain rooted in the solar interior while only a finite
section of them emerges in the form of a loop, the initial tube must reside
below the convective zone proper, in the subadiabatically stratified layer
below. This layer coincides with the region of strong rotational shear between
the rigidly rotating solar interior and the differentially rotating convective
envelope, the above mentioned tachocline.

The emergence of flux loops formed on such strong toroidal flux bundles lying in
the tachocline is driven by an instability. Often referred to as the Parker
instability, this is a buoyancy driven instability of finite wavenumber
perturbations of the tube (while the $k=0$ mode remains stable, so the tube
remains rooted in the tachocline). The first models of this process employed the
thin flux tube approximation (\citen{Spruit:TFT}) where the tube is essentially
treated as a one-dimensional object. The emergence process was first followed
into the nonlinear regime, throughout the convective zone, by
\cite{FMI:classic}; the action of Coriolis force and spherical geometry were
incorporated in later models. Since the mid-1990s models have started to break
away from the thin flux tube approximation and by now full 3D simulations of the
emergence process have become the norm (see review by \citen{Fan:LRSP}). Indeed,
flux emergence models represent probably the most successful chapter in the
research of the origin of solar activity in the last few decades.

As the total magnetic flux of the toroidal flux tube is set equal to typical
active region fluxes, emergence models are left with only one free parameter:
the initial field strength $B_0$. (Twist is introduced as a further free
parameter in 3D models.) Comparing models with different values of $B_0$ to the
observed structure and dynamics of sunspot groups, it was recognized about two
decades ago (\citen{Petrovay:strongfield}) that the value of $B_0$ must be
surprisingly high, in the order of $10^5$ G, exceeding $B_e$ by an order of
magnitude. This came as a surprise, as flux expulsion in a turbulent medium was
known to concentrate diffuse magnetic fields in tubes and amplify them to $\sim
B_e$, but not to significantly higher values. Yet there are at least four
independent lines of argument to support this assertion.

\begin{figure}
\epsfig{figure=fluxemerg, width=0.7\textwidth}
\caption{Magnetic field strength as a function of depth in the quasiadiabatic
convective zone in an emerging flux tube for initial field strenghts of 10, 100,
and 1000 kG (solid lines). Dashed line: turbulent equipartition field;
dotted line: thermal equipartition field}
\label{fig:fluxemerg}
\end{figure}

\begin{enumerate}

\item {\it Fragmentation depth.} As the rise through the convective zone takes
place on a relatively short timescale ($\sim 1\,$month), matter inside the flux
tube expands adiabatically. Most of the convective zone (except the uppermost
few hundred km) is also very nearly adiabatically stratified, and the magnetic
pressure is negligible compared to  the thermal pressure here, so the relative
density contrast between the inside of the tube and its surroundings will remain
relatively small. The field strength inside the loop is then given by
$B/B_0=\rho/\rho_0$, the '0' index referring to values at the bottom of the
convective zone. The resulting values of $B$ as a function of depth $z$ are
plotted in Fig.~\ref{fig:fluxemerg}. It is apparent that at a certain depth $B$
drops below the turbulent equipartition field strength $B_e$. Above this level
the magnetic field is unable to suppress turbulence and the external turbulent
motions will penetrate the tube. Flux expulsion processes taking place in
parallel with the further emergence of the loop are then expected to fragment
the top of the loop into a number of smaller flux tubes, resulting in the
magnetic tree structure. As we have seen, observations suggest that this
fragmentation occurs at a depth of a few tens of megameters:
Fig.~\ref{fig:fluxemerg} then clearly suggests $B_0\sim10^5\,$G.\\

\item {\it Emergence latitudes.}
For weaker tubes, the buoyancy and the curvature force are also weaker, so
the Coriolis force, independent of the field strength, will play a more dominant
role in the dynamics of the emerging loop. Tubes with $B_0\ll 10^5\,$G are so
strongly deflected by the Coriolis force that they will emerge approximately
parallel to the rotation axis. As the bottom of the convective zone lies at 0.7
photospheric radii, weak flux tubes emerging from here cannot reach the surface
at latitudes below 45 degrees, in contradiction to observations
(\citen{Choudhuri+Gilman}, \citen{Choudhuri:Coriolis}).\\

\item {\it Joy's law.} Tubes with higher values of $B_0$ will emerge
approximately radially, yet the effect of Coriolis force on them is not
negligible. The meridional component of the Coriolis force acting on the
downflows in the tilted legs of the emerging loop will twist the plane of the
loop out of the azimuthal plane, resulting in a tilt in the orientation of
active regions relative to the E--W direction. This tilt increases with
heliographic latitude, thus explaining the observed Joy's law. Quantitative
comparison between models and observations again shows that Joy's law is best
reproduced for $B_0\sim 10^5\,$G (\citen{D'Silva+Choudhuri}).\\

\begin{figure}
\epsfig{figure=sspot_propermotions_vDGPy2, width=0.9\textwidth}
\caption{Interpretation of sunspot proper motions by the emergence of an
asymmetric flux loop (after \citen{vDG+Py:asym1})}
\label{fig:asymm}
\end{figure}

\item {\it Sunspot proper motions.} The azimuthal component of the Coriolis
force acting on the downflows in the tilted legs of the emerging loop has two
consequences. On the one hand, as this component is westward in both legs, it
will distort the shape of the emerging loop so that it will become
asymmetrical, the following leg being less inclined to the vertical than the
preceding leg. On the other hand, this westward force results in a wavelike
translational motion of the loop as a whole compared to the ambient medium: the
active region is then expected to rotate faster than quiet sun plasma. It is
indeed well known that sunspots and other magnetic tracers generally show some
superrotation compared to the Doppler rotation rate of the ambient plasma. In
the past, some confusion arose due to the fact that this superrotation appears
to be time dependent: newborn sunspot groups rotate fastest, their rotation
rate steadily declines during the growth phase of the group, until it becomes
stagnant at a rate only slightly above the plasma rotation rate from the time
when the group reaches its maximal development. This apparent change in the
rotation rate, however, was shown to be a purely geometrical projection effect
(\citen{vDG+Py:asym1}), as a consequence of the asymmetrical shape of the loop
(cf. Fig.~\ref{fig:asymm}). Again, detailed quantitative comparisons of sunspot
proper motion observations with the dynamics of emerging flux tube models
(\citen{FMI+:asym}, \citen{Caligari+:movie}) indicate optimal agreement for
$B_0\sim10^5\,$G.

\end{enumerate}

In summary: flux emergence models have led to the rather firm conclusion that
solar active regions are the product of the buoyancy driven rise of strong
magnetic flux loops through the convective zone. The loops arise from small
perturbations of strong toroidal flux bundles lying in the solar tachocline, at
the bottom of the convective zone. (These tubes may be preexistent, or
alternatively they may detach from a continuous flux distribution as a result
of the perturbation.) A number of independent arguments indicate that the
field strength in these toroidal tubes is on the order of $10^5\,$G. The
origin of the tilt in active regions orientations relative to the E--W
direction is clearly identified as the action of Coriolis force on the emerging
flux loops, twisting them out of the azimuthal plane.

\section{Alternative global scenarios for the solar dynamo}

As we have seen in Sections~2 and 3, the Babcock--Leighton mechanism offers a
very attractive explanation of the cyclic polar reversals and activity
variations observed on the Sun. During the flux emergence process, the Coriolis
force twists the plane of the flux loops out of the azimuthal plane, so they
acquire a poloidal magnetic field component. With the turbulent dispersal of the
active regions, this poloidal field component contributes to the large-scale
diffuse solar magnetic field. Advected towards the poles by meridional
circulation, it ultimately brings about the reversal of the global poloidal
magnetic field of the Sun. This reversed poloidal field is then advected down
into the tachocline by the meridional circulation near the poles. Continuity
requires that plasma advected to the poles near the surface by meridional
circulation must be returned to the equator at some depth; in the simplest case
of a one-cell circulation this will occur near the bottom of the convective
zone. This deep equatorward counterflow then advects the poloidal field towards
the equator at some slower speed, while differential rotation winds it up,
resulting in an ever stronger toroidal field component. By the time it reaches
latitudes below about $35^\circ$, this advected toroidal field reaches, at least
intermittently, the intensity of $\sim 10^5\,$G and starts to erupt in the form
of buoyancy driven loops, closing the cycle. The equatorward propagation of
active latitudes, manifest in the butterfly diagram, is thus solely due to the
advection of toroidal fields by the meridional circulation.

\begin{figure}
\begin{minipage}{0.33\textwidth}
{Flux transport dynamos:}\\

\epsfig{figure=BL,width=0.9\textwidth}

\end{minipage}
\begin{minipage}{0.3\textwidth}
\epsfig{figure=modsymb,width=0.9\textwidth}
\end{minipage}
\begin{minipage}{0.33\textwidth}
{Interface dynamos:}\\

\epsfig{figure=IF,width=0.9\textwidth}

\end{minipage}
\caption{Sketches illustrating the basic concepts of the two main solar dynamo
scenarios}
\end{figure}

This scenario was already qualitatively outlined by \cite{Babcock} (with the
difference that he attributed the rise and tilt of flux loops to helical
convection). By now we have detailed quantitative models for the solar dynamo
along these lines (\citen{Dikpati+Charbonneau}, \citen{Nandy+Chodhuri:dynamo}).
As all migration phenomena in the butterfly diagram are explained by the
advection of magnetic flux in this picture, these models are known as {\it flux
transport dynamos.}

Flux transport models have become quite successful in reproducing many of the
observational details such as the shape of the butterfly diagram. This is to a
large extent due to their very good parametrizability. There are, however,
serious doubts concerning their physical consistency.

One issue concerns vertical flux transport. In order to have a poleward flux
transport near the surface and an equatorward transport near the bottom, the
surface and the tachocline must be kept {\it incomunicado} on a timescale
comparable to the solar cycle. However, simple mixing length estimates suggest
that the turbulent magnetic diffusivity in the convective zone is in the range
$10^2$--$10^3\,$km$^2$/s, so the timescale for the surface field to diffuse down
to the bottom across the the convective zone of depth $d=2\cdot 10^5\,$km is a
few years, certainly less than the solar cycle length. The above mentioned value
of the diffusivity is confirmed by calibrations based on surface flux
redistribution. So, in order to effectively decouple surface and bottom, flux
transport dynamos invariably need to rely to some ad hoc assumptions regarding
magnetic diffusivity: suppressing it in the bulk of the convective zone, making
it highly anisotropic etc.

A further difficulty is related to the flow pattern envisaged in these kinematic
models. The equatorward return flow of meridional circulation is assumed to
spatially overlap with the tachocline, i.e. the subadiabatic layer where the
toroidal field can be stably stored and where it is amplified by the strong
rotational shear. But this assumption is very dubious from a dynamical/thermal
point of view. To penetrate the subadiabatically stratified upper radiative
zone, the plasma partaking in the meridional flow would have to get rid of its
extra entropy so buoyancy will not inhibit its submergence. This, however, can
only occur on a slow, thermal timescale. Numerical estimates show that the
maximal circulation speed in the subadiabatic tachocline is a few cm/s, way too
slow for flux transport models to work.

An alternative  approach to the solar dynamo is, then, to try to construct
models from first principles, without introducing physically unsubstantiated
assumptions. Such a model cannot ignore the achievements of flux emergence
models and needs to be based on the assumption that the strong toroidal flux
tubes responsible for solar activity phenomena reside in the subadiabatic
tachocline, and then are presumably also generated there, given the strong
rotational shear.

Significant work has been done on the role of a stably stratified convective
overshoot layer, coincident witha shear layer (tachocline) in large-scale
dynamos (cf.~\citen{Tobias:penet.rev} and \citen{Brandenburg:dynamo.rev}). The
slow meridional circulation allowed here cannot be responsible for the
latitudinal migration of the toroidal field as seen in the butterfly diagram.
Instead, this must be the manifestation of a classic dynamo wave, as already
suggested by \cite{Parker:cyclonic}. The tachocline is, however, probably not
turbulent enough to support a strong $\alpha$-effect, so the site of the
$\alpha$-effect must be in the convective zone, adjacent to the tachocline,
where convective downflows diverge, resulting in $\alpha<0$ in the northern
hemisphere as required for an equatorward propagating dynamo wave at the low
latitudes where $\partial\Omega/\partial r>0$.

In these  {\it interface dynamos}, then, the dynamo wave is excited as a surface
wave on the interface between the tachocline and the convective zone. Their
classic analytical prototype was constructed by \cite{Parker:interface}. At
higher latitudes, where $\partial\Omega/\partial r<0$ this model naturally
results in a poleward propagating dynamo wave, possibly explaining the poleward
migration of unipolar areas and other phenomena in this part of the Sun. This is
an attractive feature of these models, but the question naturally arises,
whether the equatorward return flow that must be present in the lower convective
zone if not in the tachocline, i.e.\ on one side of the interface will affect
these results. This was examined by \cite{Petrovay+Kerekes:intflow} in an
extension of Parker's analytical work to the case of a meridional flow. It was
found that for parameters relevant to the solar case the meridional flow is
unable to overturn the direction of propagation of dynamo waves, nor will it
significantly affect their growth rates. For a related study of the effect of
other flux transport mechanisms on the interface dynamos see
\cite{Mason+:interface.fluxtransp}.

A number of detailed numerical interface dynamos models have been constructed
for the Sun (\citen{Charbonneau+McGregor:IFdynamo}, \citen{Markiel+Thomas},
\citen{Dikpati+:interface}). It must be admitted that at present they are unable
to reproduce the observed features of the solar activity cycle as satisfactorily
as some flux transport models can. However, this is clearly a consequence of the
fact that these models lack the kind of physical arbitrariness that
characterizes some flux kinematical transport models, where the arbitrary
prescription of flow geometries and amplitudes (esp.\ for the meridional flow)
leaves much more space to play around with parameters until an acceptable fit to
observations results.

\section{Long term variations}

In the geodynamo, field reversals and long-term variations are closely related.
Indeed, reversals are the most important kind of long term variation. In the
Sun, however, the field regularly reverses in every 11-year cycle: in fact,
reversals are the essence of the 11/22-year cycle.  Long term variations, in
turn, are a completely independent topic. It is impossible to give a
comprehensive review of this area in the present introductory paper  (see
\citen{Usoskin+Mursula:review}, \citen{Usoskin:LRSP} for much more exhaustive
overviews); instead, we limit ourselves to mentioning some salient points and
recent results.

\begin{figure}
\epsfig{figure=spotcycle, width=0.9\textwidth}
\caption{Variation of the smoothed (13-month boxcar average) relative sunspot
number with time. Solar cycles are numbered.}
\label{fig:spotcycle}
\end{figure}

Figure~\ref{fig:spotcycle} presents the variation of the relative sunspot
number in the last three centuries, for which the most reliable direct data
exist. From historical solar observations going back another century we know
that immediately before the period covered by Fig.~\ref{fig:spotcycle}, the Sun
underwent an unusally quiet period lasting nearly 70 years: in this so-called
Maunder minimum there were hardly any spots seen on the Sun at all. At the
other extreme lies the Modern Maximum: the series of unusually strong cycles
that started in the mid-20th century and seems to be just about to come to an
end now.

Various terrestrial proxies of solar activity have made it possible to
reconstruct long term activity variations (albeit not necessarily individual
cycles) over a substantially longer time span. The best results were found from
studies of the abundance of the cosmogenic $^{10}$Be isotope in Greenland ice
cores. These studies led to a reconstruction of the history of solar activity
in the last 9000 years with a time resolution of about 10 years
(\citen{Beer:SSRreview}). Recently, data with even better, annual resolution
have become available for the last six centuries
(\citen{Berggren:600yr.annual}).

One interesting result from these studies concerns the histogram of decadal
activity levels (\citen{Usoskin+:longterm.histogram}). It was found that the
overall shape of this histogram is compatible with a normal distribution;
however, significant excesses or ``shoulders'' appear at both extremes. In
other words, times of very low and very high solar activity are overabundant
relative to a Gaussian statistics. These results suggest that grand minima and
grand maxima are more than random fluctuations: they are indeed  physically
distinct states of the dynamo. Long term variations in the intermediate states,
in turn, seem to be driven by stochastic effects, resulting in nearly Gaussian
statistics.

Attempts to explain the long term variation in solar activity, as well as grand
minima and maxima, include stochastic fluctuations in dynamo parameters
(\citen{Ossendrijver2000}, \citen{Moss+:stochastic.dynamo}); nonlinear dynamos
with chaotic behaviour (\citen{Beer+:grand.minima},
\citen{Brooke+:grand.minima}) or with two alternative stationary dynamo
solutions (\citen{Petrovay:bimodal}). The shape of the histogram discussed
above suggests a bimodal solution with strong stochastic forcing resulting in
an actual solution that random walks in between the attractors for most of the
time.

It should be noted that radionuclide based reconstructions of solar activity
involve several uncertainties. On the long timescales we are concerned with,
the most important such effect is the parallel long term variation in the
geomagnetic field. The atmospheric cosmic ray flux, and thereby the
radionuclide production rate, is the net result of the shading effects of both
the interplanetary and the terrestrial magnetic fields, so long-term
normalization of the solar modulation crucially depends on the correct
subtraction of the geomagnetic contribution. Issues such as just how
exceptionally strong the most recent grand maximum (the Modern Maximum) was,
are strongly influenced by these effects.

\section{Conclusion: analogies and differences with respect to the geodynamo}

At the most basic level, the same processes generate magnetic field in
the Earth's core and inside the Sun: the shearing of magnetic field lines
by differential rotation ($\Omega$-effect) and their twisting by helical
motions ($\alpha$-effect) that obtain a preferred handedness from the action
of Coriolis forces. Also, some magnetic phenomena may have similar causes.
For example, paired flux spots at low latitudes in the geomagnetic field at
the core-mantle boundary have been tentatively explained by the expulsion of toroidal
flux tubes (\citen{Bloxham86}), in analogy to the generation of sunspots.
But although this interpretation is supported by some geodynamo models
(\citen{ChristensenOlson03}), other explanations for low-latitude magnetic
structures have been put forward (\citen{FinlayJackson03}).
Meridional flow is thought to play the essential role for reversals of
the solar magnetic field. This has also been demonstrated in a simple
reversing geodynamo model (\citen{WichtOlson04}). However, the reversal behaviour
in this model is nearly cyclic as in case of the Sun, in contrast to the
stochastic reversals of the geomagnetic field. In a less idealized geodynamo model with
random reversals, impulsive upwellings have been identified as the cause
for polarity changes (\citen{Aubert_etal08}). These upwellings transport and
amplify a multipolar magnetic field from depth to the outer boundary.
While possible analogies
between the solar dynamo and the geodynamo can stimulate our thinking, we
must keep their limitations in mind.

Which differences in physical conditions lead to the rather distinct
behaviour of the solar dynamo and the geodynamo?
One important difference is that the plasma in the
solar convection zone is sufficiently compressible and that the
field strength is high enough so that magnetic pressure and magnetic buoyancy
play an essential role for the dynamics of flux tubes. These effects are
probably unimportant in Earth's core. Another difference is that the Coriolis
force has a stronger influence in the geodynamo than it has in the slowly
rotating Sun. This notion is supported by the observation that much more
rapidly rotating stars of low mass seem to have strong large-scale
magnetic fields that are frequently dominated by the axial dipole component
(\citen{Donati_etal08}). Their observed field strengths
follow the same scaling law as the observed fields of Earth and Jupiter and
the field intensity found in geodynamo models at sufficiently rapid rotation
(\citen{Christensen_etal09}).
A third difference arises from the much slower motion and therefore lower magnetic
Reynolds number in the geodynamo.

The moderate value of the magnetic Reynolds number makes the magnetic induction
process in the Earth's core amenable to direct numerical simulations without
the need to take recourse to turbulent magnetic diffusivities or parameterized
turbulent $\alpha$-effects. This is perhaps the most important reason for the
success of geodynamo models in reproducing many observed properties of the
geomagnetic field without need for ad-hoc assumptions. However,
our more limited knowledge of the geomagnetic field
at the top of the core, in comparison to that of the field in the solar
photosphere, makes the task simpler for a geodynamo modeller. Also,
helioseismology has revealed the distribution of zonal flow
in the solar convection zone and a fully consistent solar dynamo model must
reproduce this flow pattern as well as the magnetic field properties.
Comparable information is lacking for the Earth and a geodynamo model can be
declared successful once it captures the general properties of the large-scale
geomagnetic field.

\begin{acknowledgements}
K. Petrovay's work on this review was supported by the Hungarian
Science Research Fund (OTKA) under grant no.\ K67746 and
by  the European Commission through the RTN programme SOLAIRE (contract
MRTN-CT-2006-035484).\\

\end{acknowledgements}

redpajama_set_name: RedPajamaArXiv


text:
Macron thanks Allied Forces as he joins ceremony marking 75th D-Day anniversary
June 5 2019, 12.53pm
Philip May, left to right, Queen Elizabeth II, French President Emmanuel Macron, Prime Minister Theresa May and the Prince of Wales during the commemorations at Southsea Common in Portsmouth (Andrew Matthews/PA)
French President Emmanuel Macron thanked Allied Forces on behalf of his country as he joined the Queen and hundreds of veterans at a national commemorative ceremony to honour those who fought in the D-Day landings.
Mr Macron is among world leaders representing the Allied nations involved in Operation Overlord, including Canadian Prime Minister Justin Trudeau and US President Donald Trump, who is coming to the end of a three-day state visit to the UK.
Other guests at the Portsmouth event marking 75 years since D-Day include German Chancellor Angela Merkel, Australian Prime Minister Scott Morrison, premier Charles Michel from Belgium, Czech Prime Minister Andrej Babis and President Prokopis Pavlopoulos from Greece.
US President Donald Trump speaking during the commemorations (Andrew Matthews/PA)
Three hundred veterans are also present, while 60,000 members of the public are expected to attend the Portsmouth Naval Museum.
A segment of the event saw a tribute to the agents of the Special Operations Executive, a unit which supported the French Resistance.
Mr Macron read the last letter of a young resistance fighter Henri Fertet, executed at just 16-years-old.
Before he began, he said: "First, let me thank you sincerely, on behalf of my nation."
Also joining the ceremony are the prime ministers of Luxembourg, Xavier Bettel; the Netherlands, Mark Rutte; Norway, Erna Solberg; and Poland, Mateusz Morawiecki, and Slovakia's deputy prime minister Richard Rasi.
They all met the Queen before the event began – a first for Mr Macron – and then posed for a group photograph with the monarch and the Prince of Wales.
Government ministers Penny Mordaunt, left to right, Philip Hammond, Sajid Javid and Jeremy Hunt joined the commemorations (Andrew Matthews/PA)
President Trump read a prayer written by his predecessor Franklin D Roosevelt.
He read the piece which was originally delivered to the US nation by President Roosevelt on the evening of D-Day – June 6 1944.
Mrs May read a letter from Captain Norman Skinner of the Royal Army Service Corps, to his wife Gladys on June 3 1944.
The letter was in his pocket when he landed on Normandy's Sword Beach on D-Day but he was killed the following day, leaving his wife and two young daughters.
A guard of honour formed of military personnel from the Royal Navy, Army and RAF marched through the spectator aisles and on to the main stage.
Musicians from the Band of the Royal Marines played a fanfare when the Queen arrived in the royal box, with the Tri-Service Orchestra performing the national anthem.
Speaking ahead of the service, Sergeant John Jenkins, 99, from Portsmouth, said he was "overwhelmed" to be a part of the day.
"Obviously, I will think of all my mates that didn't come back," he said.
"I can't say any particular one because we were all comrades together, that was the thing.
"We were all comrades together and that's what carries us through – the comradeship."
Mr Trump and Theresa May arrive for the event (PA)
He was serving with the Pioneer Corps on D-Day and landed on Gold Beach on June 8 1944.
Considered a turning point in the Second World War, Operation Overlord saw thousands killed and injured after its launch on June 6 in 1944.
The commemoration event marks the first time the UK has hosted this many world leaders outside a formal summit since the 2012 Olympics.
Mrs May will be making her final official appearances as the British Prime Minister during the D-Day commemorations, which continue on Thursday across Normandy.
She will call for unity in western Europe, saying: "The global challenges we face today are different in their origin and nature.
"But as we confront new and evolving threats to our security, it is more important than ever that we continue to stand together in upholding our shared values and way of life.
French President Emmanuel Macron and Theresa May (PA)
"As I host leaders from around the world today to mark this significant moment in our shared history, we will together reflect on the continued importance of the western alliance for all our countries' security and prosperity."
An hour-long production telling the story of the invasion was being played to the crowds, featuring testimony from veterans, before theatrical performances, live music and a flypast.
Afterwards, world leaders were meeting to discuss the western alliance and security following a reception with veterans.
From the deck of the aircraft carrier HMS Queen Elizabeth, Mrs May and Defence Secretary Penny Mordaunt will then wave off the crowds of veterans who are set to retrace the journey they made across the channel 75 years ago.
This time they will be followed by a flotilla of Royal Navy vessels.
Meanwhile, hundreds of veterans are flocking to northern France and Portsmouth as well as to events around the country to mark the occasion.
View of #Portsmouth as I arrived this morning for #DDay75. Huge thank you to everyone in my home city who has worked on the events today, and all the residents too who are putting up with rather a lot.  I'm so proud of my city today and so will the world watching. @DefenceHQ  pic.twitter.com/gxYziEOhwO
— Penny Mordaunt MP (@PennyMordaunt) June 5, 2019
On Wednesday afternoon, veterans Harry Read, 95, and John Hutton, 94, will parachute into Normandy in honour of comrades they lost when they first made the descent 75 years ago.
Alongside around 280 paratroopers, they will take part in the jump onto fields at Sannerville – the drop zone for the 8th Midlands Parachute Battalion during D-Day.
In the evening, a vigil and silent march will take place at Pegasus Bridge which was the scene of a 15-minute skirmish to take hold of the pathways over the Caen Canal and River Orne. This was one of the first places British troops liberated on D-Day.
D-Day veteran appeals for return of medal lost during 75th anniversary event
More than 1,000 walkers take on Cateran Yomp trek to mark 75th anniversary of D-Day
Fife Parachute Regiment veteran presented with France's highest military honour on 75th anniversary of D-Day
Dundee D-Day veteran dies days before 75th anniversary of historic invasion
Battle of Normandy
Royal Army Service Corps
UK Armed Forces


text:
The Gay and Lesbian Coalition of Kenya (GALCK) joins Kenyans and people around the world in marking the World AIDS Day. Established in 1988 to raise awareness on the AIDS pandemic and the lives lost to the disease, today marks 30 years of concerted dedication and solidarity towards ending AIDS.
Today we not only remember the millions of lives lost to AIDS and other related illnesses, we celebrate the millions of people whose courage and light shines bright; reminding us that HIV is no longer a death sentence. We celebrate the dynamic models of multilateral funding such as Global Fund and PEPFAR whose commitment to ending AIDS facilitates access to life saving anti-retroviral treatment across the world.
The road to ending AIDS is far from over. Whereas the Kenyan HIV response has been progressive thus far, widespread homophobia, biphobia, transphobia, stigma, discrimination and targeted sexual and gender-based violence continue to impede access and uptake of quality HIV services among gay men and other men who have sex with men, female and male sex workers, people who use and inject drugs and transgender people.
Criminalization of consensual sex between two male adults and sex work still exists in Kenya. Harm reduction services are impacted by the misguided perception that they promote the use and distribution of drugs. Transgender HIV programming is yet unrecognised by the state, thus impacting access to trans affirming healthcare. In addition, no attention is paid to the socio-economic and political susceptibilities of lesbian, bisexual and queer womxn to HIV.
In the lead to the 2030 goals of ending AIDS, our strategies MUST be informed by data, MUST adopt a human rights approach and MUST be intentional about leaving no one behind.
← Decriminalisation of Consensual Same Gender Sex in IndiaJoint Statement on the Judgement on Consolidated Petitions 150 & 234 of 2016 →


Students and staff at Bancroft Elementary School ended American Education Week with Guest Readers Day and the school's famous Door Tour. For the Door Tour, teachers and students decorated their classroom door with ideas from their favorite book. Click on the links below for slideshows of our Guest Readers Day and Door Tour.
Please take a look at the December Calendar to see all the important events happening at Bancroft Elementary School this month.
Students and staff at Bancroft Elementary School kicked off American Education Week on Monday with schoolwide sustained silent reading. Students and staff took time to silently read their favorite book together in the first-floor main hallway. It is a great way to show the importance of reading to students.
We will have a special activity each day this week to promote American Education Week. Tuesday is Read Me Day, where everyone will wear something with words on it. Wednesday is Math Day, Thursday is Guest Reader Day, and Friday is our famous Door Tour Day. Look for more website posts each day this week.
On Tuesday, students and staff at Bancroft Elementary School wore clothes with words on them. This was another way to emphasize the importance of reading to our students during American Education Week. Remember: Wednesday is Math Day, Thursday is Guest Reader Day, and Friday is the school's famous Door Tour Day.
Bancroft Elementary School students, parents, and staff had a great time playing Bingo last Friday night. Students won prizes and the proceeds from the Bingo games benefited the school.


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Mid-Coast Transit Constructors Wins NRC 2021 Large Project of the Year
The National Railroad Construction and Maintenance Association (NRC) has awarded the Mid-Coast Transit Constructors (MTCT) – a joint venture of Stacy and Witbeck, Herzog and Skanska – with the 2021 Large Project of the Year award for its work on the Mid-Coast Corridors Project, a $1.4billion, 11-mile extension of SANGAG's (San Diego's Association of Governments) Blue Line.
The six-year SANDAG project extends the Blue Line through the University of California San Diego campus to La Jolla. The site terrain and elated congestion made the project particularly challenging and complex. Seven miles of the project are within the Los Angeles-San Diego (LOSSAN) corridor, one of the nation's busiest rail corridors, running nearly 60 BNSF, Amtrak and No. County Transit District (NCTD) COASTER trains daily. The northern four miles of the project is elevated and crosses Interstate 5 (I-5) twice.
The scope of work included the following components:
Double-tracking five miles of the existing line to improve efficiency and accommodate the new light rail alignment,
Constructing a total of 25 track-miles of ballast track, seven track-miles of direct fixation track, and track on 21heavy rail, light rail, and roadway bridges,
Installing nine major aerial and at-grade stations,
Constructing a parking garage,
Installing an arched roadway bridge over I-5,
Excavating 1,450,000 cubic yards of earth work and installing 500,000 square feet of retaining walls,
Performing work related to utilities, channel reconstruction, highway widening, roadwork, a two-mile bike pathway, and systems.
The joint venture thoroughly planned work and employed innovative approaches before and throughout the six-year project to address planning and construction challenges. They delivered the project under budget, ahead of schedule and with an exemplary safety record that was well below industry average.
"The MCTC team exceeded our expectations for partnership, collaboration, performance, schedule achievement, and issue resolution," attest Jacobs Engineering Construction Manager Jim Starling. "The team managed the project cost and schedule and were able to deliver the project on time and within SANDAG's budget, with no claims or disputes. … it has been a pleasure to work with the MCTC team for the past six years … (the project) has made a positive impact on the community and has improved the region's transportation system dramatically."
The joint venture leveraged their expertise during preconstruction when it determined it was imperative to relocate an existing control point in the LOSSAN corridor, even though it was not in the project scope. After several planning and presentation sessions (and before they even had a construction contract), the joint venture convinced SANDAG that relocating the control point early would allow flexibility to switch train traffic through the corridor to provide sufficient space to build the project. The relocation work was completed safely and on time and opened the door for the rest of the work in the corridor.
The team's efforts to thoroughly plan work contributed to successfully completing another key milestone: the complex work under the SR-52/ I-5 interchange to build what was referred to as Shoofly 2. This work involved completing a complicated progression of logically tied steps that methodically opened up a very narrow corridor under the interchange that evolved from a single track, a small channel, and a bike path to four tracks plus a maintenance track, a large channel, and a bike path. While this work progressed, crews were relocating utilities and building the flyover foundations, columns, and caps in phases as governed by Shoofly 2.
Numerous funding sources involved indifferent elements of the project presented a major cost-control challenge. Federal, state, and local funds were used, and each had different reporting requirements. Adding to the complexity was the fact that the Mid-Coast Corridor project was actually eight separate projects delivered under one program. The management team held weekly production meetings and monthly cost meetings to review labor production, costs against the budget, and schedule achievements. The joint venture saved SANDAG more than $85 million and many months off the schedule through its preconstruction value engineering efforts. Benefits accrued during construction as the joint venture continued to come up with innovative ideas to reduce cost, schedule, and risk.
Jacobs Engineering and Kleinfelder served as the construction management firm and WSP, HDR and Kleinfelder Wong were the lead engineer. They contributed to the successful completion of the project along with the following subcontractors and suppliers:
Subcontractors:
Modern Railway Systems
McCarthy Building Companies
Lucas Builders
SRK Engineering
L.B. Foster
Nortrak
Robertson's Ready-Mix
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Ragnar Benson Construction LLC.
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text:
Faith Evans Takes Us Back With An 'Ode To '95'
AudioDiva
It has been 18 years since Faith Evans released her debut album, Faith. Eighteen. Almost two decades. Yeah, marinate on that. Still what has always remained the same is that the First Lady of Bad Boy has been a mainstay in the R&B game (save for a few little hiccups along the way) as she continues to work that grind with each new project she puts herself into, and as always she's not letting you forget that she's been holding it down since day one. With the unreleased cut, "Recognize (Ode To '95)" she does just that, as she takes us on a retrospect of how it all began with names drops of Puff Daddy (Diddy will always be Puff Daddy to me, okay) and her late husband The Notorious B.I.G. tossed into a slick throwback mix. The track is just the right kick-start to Evans' new online series #fizzyfridays, where she'll weekly treat fans with brand new music for a rumored upcoming album. Now, I don't know about you, but after hearing "Recognize" I have a sudden urge to give Faith a spin and do the time warp back to when Evans was a "hot blonde chick from the Jersey bricks" and when R&B music was in its golden prime -- just this time I can enjoy listening without the pain of braces and pre-teen angst.
TAGS: audio, diddy, faith evans, puff daddy, the notorious b.i.g.
Previous: Om'Mas Keith Has The 'Pulse' To The 'City' Next: 'Smash' Loads Up On Star Power For Season 2


text:
Liberdade, Liberdade (en español: La Dama de la Libertad) es una telenovela brasileña producida y exhibida por TV Globo entre 11 de abril y 4 de agosto de 2016. Fue la 6ª "novela de las once" exhibida por la emisora.

Escrita por Mário Teixeira, con la colaboración de Sérgio Marques y Tarcísio Lara Puiati, basado en el argumento de Márcia Prates, libremente inspirada en el libro Joaquina, Hija del Tiradentes, de Maria José de Queiroz; cuenta con dirección de André Cámara, João Paulo Jabur, Pedro Brenelli, Bruno Safadi y Vinícius Coimbra, también director artístico.

Contó con Andreia Horta, Bruno Ferrari, Dalton Vigh, Lília Cabral, Zezé Polessa, Ricardo Pereira, Caio Blat, Yanna Lavigne, Maitê Proença, Rômulo Estrela, Sheron Menezzes, Vitor Thiré, Joana Solnado, Juliana Carneiro da Cunha, Marco Ricca, Nathalia Dill y Mateus Solano en los papeles principales.

Trama
En la ciudad de Vila Rica, cuenta la historia de la hija de Tiradentes (Thiago Lacerda), Joaquina (Andreia Horta) que después de ver la muerte de su padre en la forca, conoce Raposo (Dalton Vigh) un minero simple. Los dos viajan para Portugal. Allá ella es adoptada por él, que junto con su nueva familia formado por: André (Caio Blat) y Bertoleza (Sheron Menezzes), vuelven para Vila Rica.

Ya con nombre diferente Joaquina ahora Rosa queda espantada con tanta pobreza en Vila Rica. Ella conoce el intendente Rubião (Mateus Solano), un hombre ambicioso y determinado por el poder. Él hace de todo para haber lo si amor

Rosa conoce Virgínia (Lília Cabral) amiga de su padre, dueña de un cabaré. ellas tan amigas Virgínia revela que es una revolucionaria, espantada Rosa le gustó saber, pues con la revolución en Vila Rica las personas negras o pobres serían libres.

Elenco

Participaciones especiales

Galería

Controversia
 Escena de sexo gay
Libertad, Libertad fue responsable por exhibir la primera escena de relación sexual entre homosexuales de la teledramaturgia brasileña. La escena fue exhibida el día 12 de julio de 2016, en una actuación de los personajes de Caio Blat y Ricardo Pereira, dejando de lado las normas de la sociedad de la época donde presenciam (Siglo XIX). Los productores de la novela discutían al respeto de la intolerancia entre los negros, las mujeres y religiones de matriz africana, y resaltaron: "En aquella época, la sodomia era considerada crimen, con enforcamento. No era ni prejuicio, porque el concepto de homosexualidad ni existía, era tratado como acto inatural, como pecado." Sin embargo, una semana antes del capítulo ser exhibido, protestas de entidades religiosas comenzaron a circular en internet. Una fanpage católica del Facebook promovió boicot a la Red Globo, divulgando un alerta, afirmando que el día de exhibición del capítulo "el demonio actuará, por medio de esta emisora, que transmitirá escenas de sexo gay en una de sus novelas! Usted, católico, no puede servir a dos señores". Antes de la escena ir al aire la Bancada Evangélica, de la Cámara de los Diputados, condenó haciendo una campaña contra la exhibición de la escena, llevando algunos evangélicos a hacer marcha contra la escena.

Audiencia
Libertad, Libertad registró 27 puntos en su capítulo de estrena, según datos del Kantar IBOPE Medía aferidos en São Paulo. Cerró con media general de 18 puntos, éxito. Pero inferior a la antecesora Verdades Secretas que alcanzó media de 20 puntos. Su último capítulo alcanzó 22 puntos, Verdades Secretas había dato 27 puntos en la misma ocasión. Su récord es de 28 puntos, alcanzados en 1 de agosto de 2016.

Colombia a través del canal Señal Colombia estrenó esta novela en el horario de las 10 p.m. en agosto de 2021.

Telenovelas de 2016
Telenovelas de Brasil
Telenovelas de Rede Globo
Telenovelas en portugués
Telenovelas iniciadas en 2016
Telenovelas finalizadas en 2016

redpajama_set_name: RedPajamaWikipedia


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Uruguay goes green with solar-powered airport
Madelon Kunst 19 September 2018 1 March 2019 No Comments on Uruguay goes green with solar-powered airport
In terms of health, Uruguay is one of the leading countries in Latin America. Besides its high quality health care at an affordable price, the small country keeps reducing its water and air pollution, continually becoming greener and healthier. With a solar-powered airport as its latest sustainable project, Uruguay has set the stage for the rest of the world to follow.
Eco-friendly airport
Uruguay's Carrasco Airport in Montevideo recently installed a solar photovoltaic system that will provide the airport with energy, making it the first airport in Latin America to use self-generated energy.
Unfortunately, going green didn't come cheap: the installation required an investment of five million dollars and there is still a lot of work to be done. Estimated to generate around 11% of the terminal's annual energy consumption, the airport has a long way to go before achieving its goal of being the first sustainable and energy-efficient airport in the world. Nevertheless, the solar installation is a huge step in the right direction.
Green and keen Uruguay
It's not only the airport making sustainable progress. Uruguay as a whole is truly a sustainability success story. While most countries are failing to reach the goals of the Paris Agreement on climate change, Uruguay now gets 97 to 100% of its electricity from renewable sources, such as hydropower, wind and solar energy. Sometimes the country even has a surplus of sustainable electricity, which they export to their Argentinian and Brazilian neighbours, the same countries that used to supply Uruguay with oil before its sustainable shift.
Healthier environment, healthier you
By going green, Uruguay hasn't only become more independent from its neighbours. It's also become healthier. Traditional energy sources, such as coal and gas, emit water and air pollution, both of which are proven to be related to a number of life threatening health issues, such as breathing problems, heart attacks and neurological damage. Quite simply, most sustainable energy sources don't produce this air and water pollution, making the environment a healthier place for you. With its efforts to use increasing amounts of green energy, Uruguay isn't only a sustainable place to live, but also a healthy one.
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Quercus glauca Thunb.
Article from Bean's Trees and Shrubs Hardy in the British Isles
Bean's Trees and Shrubs
Synonyms: Q. annulata Sm.; Cyclobalanopsis glauca (Thunb.) Oerst.
An evergreen tree up to 50 ft high, or a large shrub; young stems brown or purplish brown, downy at first, soon glabrous. Leaves elliptic, oblong, or narrow-ovate, sometimes broadest slightly above the middle, acuminate at the apex, usually tapered, sometimes rounded, at the base, glabrous above, the underside glaucous and more or less permanently coated with appressed silky hairs, main veins in eight to twelve pairs, prominent beneath, margins of leaf sharply toothed in the upper part; petiole up to about 1⁄2 in. long. Fruits one to three in each cluster, ripening the first season; acorns about 3⁄4 in. long, about one-third enclosed in a downy cup with six or seven raised rings.
Interpreted in a broad sense, this species has a very wide distribution in E. Asia, from Japan and Formosa through China to the Himalaya, where it occurs in the outer ranges and does not ascend above 5,000 ft; it is also found in the Khasi Hills. It is variable and should perhaps be divided into subspecies. Although first described from Japan, the earliest introduction was from Nepal in 1804. Later the Kew collector Richard Oldham sent it from Japan (c. 1861), and it is also in cultivation from seeds collected by Wilson in W. China. According to him it is the commonest evergreen oak in W. Hupeh and E. Szechwan, where it grows from river-level to 5,000 ft. He described it as a 'handsome tree with a bushy, flattened-round head of widespreading branches'.
Q. glauca is very rare in gardens and only suitable for the mildest parts of the country. There is an example at Caerhays in Cornwall of 20 × 11⁄2 ft (1971) and a slightly smaller one at Exbury, Hants.
From the Supplement (Vol. V)
The specimen at Caerhays, Cornwall, measures 36 × 41⁄4 ft (1984).
'Quercus glauca' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/quercus/quercus-glauca/). Accessed 2022-01-19.
Q. annulata Sm.
Cyclobalanopsis glauca (Thunb.) Oerst.
Quercus euboica
acuminate
Narrowing gradually to a point.
(pl. apices) Tip. apical At the apex.
Lying flat against an object.
glabrous
Lacking hairs smooth. glabrescent Becoming hairless.
Grey-blue often from superficial layer of wax (bloom).
Egg-shaped; broadest towards the stem.
petiole
Leaf stalk.
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