A Piece of Mars: Gray dunes have migrated over reddish rock, moving toward a narrowing cleft surrounded by tall tan cliffs. Bright lines on the dunes are exposed internal layers (bones of the dunes, really) that show you where the lee-side slopes once were (so you can tell they’ve moved to the left). The cliffs are made of layered rocks (extra points if you can find the fault), suggesting these are sedimentary layers, laid down long ago in Mars’ geologic past. The whole HiRISE image is worth a long look, it’s really amazing. (HiRISE ESP_049009_1520, NASA/JPL/Univ. of Arizona)
Chelsea Manning, serving a 35-year term for leaking a cache of classified military documents to WikiLeaks, had her sentence commuted Tuesday by President Barack Obama. The president, with just days remaining in his presidency, said Manning can be freed on May 17 of this year instead of 2045.
The 29-year-old Army private was court-martialed in 2013 for forwarding a cache of classified documents to WikiLeaks. After being convicted of leaking more than 700,000 documents and video, Manning—then known as Bradley—announced that she is a transgender woman and would be going by the name Chelsea.
Manning has been both reviled and lauded for her 2010 document dump and has been in prison longer than any other convicted US leaker. In a military first, Manning was approved in 2015 for hormone therapy as part of transition-related care, nearly a year after she made demands for such treatment.
The brain can reorganize itself in the face of a traumatic injury or a sensory disability. For example, in deaf mammals, the auditory processing neurons of the brain may be rewired to handle other stimuli. But we haven’t been able to figure out if this reorganization is task-specific—will the circuits be recruited to do the same tasks?—or more general.
A recent study published in PNAS suggests that, in at least one case, these brain circuits are repurposed for a similar task. When deaf people were asked to interpret visual rhythms (represented by a flashing light), the same auditory processing regions used to listen to rhythms were activated.
This study used fMRI to look at the brain activation of both congenitally deaf subjects and those with normal hearing. While in the fMRI machine, all subjects were asked to discriminate between different rhythms of flashing lights. As a control, all subjects were also asked to look at a light that flashed with a regular, predictable pattern. Hearing subjects were then asked to discriminate between different auditory rhythms as well. As a control, these subjects were asked to listen to a similar noise occurring in a regular, consistent pattern.
Standing out against the linear grid of city streets and pedestrian crossing stripes, over 170 strange brick circles can be found embedded in the pavement throughout San Francisco. At their center: a metal circle that looks a lot like a manhole cover for sewer access.
In fact, these brick outlines are a surface expression of something much larger below: a series of huge cisterns (holding tanks) that form an integral part of the city’s Auxiliary Water Supply System.
The fire department’s AWSS is comprised of water reservoirs, pump stations, suction connections, fireboats and cisterns, all designed to help deal with emergencies should conventional water systems fail.
Following the infamous 1906 earthquake, fires erupted across San Francisco. In many places, the flames wreaked havoc for days. An estimated 3,000 people were killed and over 80% of the city was destroyed. The devastation was made worse by the failure of emergency water systems in the wake of the quake. Among other issues, water mains broke and firefighters found it hard bring vehicles with water across the city’s rubble-filled streets to areas in need. In the aftermath, the AWSS (and its cistern system) was developed to put redundancies in place and prevent similar failures in the future.
The cisterns range in capacity from 75,000 to over 200,000 gallons each, able to store a total of over 11,000,000 gallons citywide. They are made of concrete and steel rebar for strength and durability, designed to resist damage in case of earthquakes.
Their positions across the city make it possible for firefighters to access local water sources should pipes break or roads become impassible. Usually, their presence is indicated by a circle of bricks (or in some cases: a square). Up close, the access covers can be readily identified, labeled with CISTERN and S.F.F.D (San Francisco Fire Department).
In case of fire, trucks can pull up right up and suck water directly from the cistern to battle the flames.
The AWSS has other clever systems in place, too, that hide in plain sight. For instance: there are sets of blue-, red- and black-topped hydrants that tap into three different reservoirs (Twin Peaks, Ashbury Street and Jones Street, respectively). If one of these sources gets tapped out the others can be brought into play.
And if all else fails: brackish water can be pumped from the San Francisco Bay itself to meet demand — each of two pumping stations can push 10,000 gallons per minute as needed. These, in turn, are backed up by a pair of fireboats that can likewise supply salty water.