Bridget Evans’ service dog, Hero, attended all her classes, so she thought he deserved to graduate too.
May 17, 1954: The Supreme Court Rules on Brown v. Board of Education
On this day in 1954, the U.S. Supreme Court ruled unanimously that racial segregation in public schools violated the Fourteenth Amendment to the Constitution, which says that no state may deny equal protection of the laws to any person within its jurisdiction.
Although the decision did not succeed in fully desegregating public education in the United States, it put the Constitution on the side of racial equality and galvanized the nascent civil rights movement into a full revolution.
Can you name all the key players behind Brown v. Board of Education? Revisit the landmark case with PBS’ The Supreme Court site.
School integration, Barnard School, Washington, D.C., 1955 (Library of Congress).
Blink and you’ve missed it. Researchers in the US have captured the world’s first X-ray images of lightning, by creating a special camera that can capture radiation at 10 million frames per second. They presented their new findings at the American Geophysical Union (AGU) Fall Meeting in San Francisco and they say that this new view of lightning could help to solve some of the mysteries of this spectacular natural phenomenon.
The research was carried out at the International Center for Lightning Research and Testing, located in Florida. It is one of the few sites in world where lightning is initiated and studied under controlled conditions. By firing rockets with trailing wires into thunder clouds, scientists are able to generate electric fields that are large enough to trigger bolts of lightning, which then propagate back down towards the rocket launch tower.
Joseph Dwyer and colleagues at the Florida Institute of Technology became interested in the fact that lightning emits X-rays as it propagates through the air, a phenomenon that was only noted in the past decade. But given that X-ray sources in lightning travel through the Earth’s atmosphere at velocities approaching the speed of light, it is difficult to catch them on camera before they disappear. In addition, they cannot be imaged with standard mirrors and lenses because huge amounts of material are required to prevent X-rays and gamma rays from entering through the sides of a camera.
Dwyer’s team has created a customized camera that has 30 detectors made from a combination of sodium iodide and photomultiplier tubes, each measuring 3 × 3 inch. The device, which is approximately the size of a standard refrigerator, is also equipped with a 3 inch pinhole aperture, and can record X-rays at 10 million frames per second. “This is actually a very old technique for making images, like that seen in a camera obscura,” Dwyer says.
During July and August this year, Dwyer’s team studied four rocket-triggered lightning flashes at the Florida test site. Each flash lasted for approximately two seconds and the resulting sequences of images revealed that X-rays emerged primarily from the vicinity of the lightning tip as it propagated towards the Earth. As the lightning crashed into the control tower it also triggered large bursts of gamma radiation, which were also captured by the camera.
“For the first time we’re catching a glimpse of lightning in the X-ray emission,” says Dwyer. “We’re seeing lightning as Superman would see it with his X-ray vision”.
Credit: James Dacey/physicsworld.com
From Michael Marten’s series, Sea Change, which explores rising sea levels from regular tides and also climate change. His statement:
‘Sea Change’ is a study of the tides round the coast of Britain. The views in each diptych are taken from identical positions at low tide and high tide, usually 6 or 18 hours apart.
I am interested in showing how landscape changes over time through natural processes and cycles. The camera that observes low and high tide side by side enables us to observe simultaneously two moments in time, two states of nature.
Recent landscape photography often focuses on human shaping (and reshaping) of the environment - urbanisation, globalisation, pollution. Even when critical and committed, this approach can emphasise, even glamorise, humankind’s power over nature. I’m interested in rediscovering nature’s own powers: the elemental forces and processes that underlie and shape the planet.
The tides are one of these great natural cycles. I hope these photographs will stimulate people’s awareness of natural change, of landscape as dynamic process rather than static image. Attending to earth’s rhythms can help us to reconnect with the fundamentals of our planet, which we ignore at our peril.
‘Sea Change’ also comments on climate change. The tide floods in and quickly recedes again, but rising sea levels will flood our shores and not recede for thousands or millions of years. Many of the views in these pictures may have disappeared in 100 years’ time.
— Michael Marten
The Sad Diaries of Cats
Submitted by WageSlavery
TOP: Anatomy of a Bacteriophage
MIDDLE: A Bacteriophage Attacking a Bacterium
BOTTOM: What a Phage Does to its Host
The cycle begins when the virus uses its tail fibers to attach itself to its victim. The details of what happens next vary, but the process is always the same: the phage’s genetic material, which is located in its head, enters the bacterium.
Here, we’ll use T4, a well-studied phage infecting the Escherica coli bacterium, as an example.
(1) T4 contracts its tail sheath which pushes a tube located within the tail through the membrane of the bacterial cell.
(2) The phage’s DNA is passed through the tube into the cell, where it takes control, brutally stops many of its vital functions and forces it to churn out new virus components – heads, tails, tail fibers – in production-line style.
(3). Finally, enzymes dissolve the wall of the bacterium from the inside and the newborn bacteriophages reach the exterior, ready to attack new victims.
(4) But these viruses proceed very selectively as they do so. Most of them attack only a subgroup of a single bacterial species. Generally, they don’t touch animal or human cells, which is why they are harmless to human beings.
[ X - images and basic text]
Iron Man 3 Dance!
Caution: May cause seizures, anger or throwing up in your mouth a bit.
Black Sea Nettle (Chrysaora achlyos)
Also known as the black jellyfish, the black sea nettle is a species of true jellyfish found throughout the Western seaboard of the Pacific Ocean. Like other scyphozoan jellies the black sea nettle is carnivorous and will feed on any plankton that swim into its stinging tentacles. Its sting is powerful enough to kill or stun small animals but will only cause a painful sting that will last for about forty minutes in humans.