Potato pathogen

"...I saw the dying, the living, and the dead, lying indiscriminately upon the same floor, without anything between them and the cold earth, save a few miserable rags upon them. To point to any particular house as a proof of this would be a waste of time, as all were in the same state; and, not a single house out of 500 could boast of being free from death and fever..."– Irish artist James Mahoney, 1847

The blight that struck the potato crops in Ireland between 1845 and 1852 was caused by Phytophthora infestans, a fungus-like microorganism that attacks through the leaves. Using specimens of leaves from that time period, found in the Botanical State Collection in Munich and Kew Gardens in London, British scientists were able to extract DNA from the plants and sequence their genomes to track the spread of the pathogen. They discovered that the strain of P. infestans which devastated Ireland had diverged from the strain that originated in Mexico and spread to the rest of the Americas. It spread to Europe in the 1800s, but – unlike some of the strains which continue to affect crops to this day – died out in the early 1900s. More than 1 million people died as a result of the Irish potato famine and another million emigrated to England, America, and Australia. That amounted to as much as 25% of the population, from which Ireland (now consisting of Northern Ireland and the Republic of Ireland) has still not recovered.

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Slumping stained glass

I worked with stained glass for years – both the copper foil method and the lead came method that was used in medieval times –and never heard that supposedly glass is a liquid at room temperature. The "proof" of this, according to tour guides and high school chemistry teachers, is that the glass in cathedral windows is thicker at the bottom than at the top. In fact, glass is an amorphous solid, something in structure between a liquid and solid, but for it to flow slowly downward would take not centuries but billions of years. "A mathematical model shows it would take longer than the universe has existed for room temperature cathedral glass to rearrange itself to appear melted." The disparity in the thickness of the glass is due to the way it was made by the European glassblowers of the Middle Ages. They crafted glass cylinders which they then flattened into panes. The thicker parts of the uneven panes were installed at the bottom to avoid the windows being top-heavy and less stable.

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Alligator snags

Five years ago, chemists at Louisiana State University found that blood from the American alligator can successfully destroy 23 strains of bacteria – including strains known to be resistant to antibiotics – and significant amounts of HIV. Now an international team of scientists is studying alligator jaws in hopes of applying the secrets of their tooth regeneration to people. Like us, alligators have a layer of epithelial cells called dental lamina, but unlike ours the stem cells within it grow new teeth repeatedly. They hope to identify the cellular and molecular mechanisms that will allow them to stimulate the growth of a replacement tooth when an adult tooth is lost. “Alligator teeth are implanted in sockets of the dental bone, like human teeth. They have 80 teeth, each of which can be replaced up to 50 times over their lifetime, making them the ideal model for comparison to human teeth,” explains team lead Ping Wu of the University of Southern California.

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Rock, paper, scissors

ROCK: Paleontologists have been discovering and describing many middle Cambrian creatures from the Stanley Glacier exposure of the Stephen Formation ever since 1996, when a German hiker discovered fossils on the trail in Canada's Kootenay National Park.

PAPER: Scientist David Legg of Imperial College London details one of the 505-million-year-old fossils in this month's issue of The Journal of Paleontology. The 1.5" (4 cm) creature is a distant ancestor of lobsters, crabs, spiders, centipedes, millipedes, and scorpions. It used its many legs to scuttle along the seafloor and its compound eyes, located on stalks on top of its head, to search for prey hiding in the sediment.

SCISSORS: But its most distinguishing feature, the enlarged pincer-like frontal claws that it used for the capture, is what inspired Dr. Legg to name the fossil Kootenichela deppi after American actor Johnny Depp. “When I first saw the pair of isolated claws in the fossil records of this species I could not help but think of Edward Scissorhands....In truth, I am also a bit of a Depp fan and so what better way to honour the man than to immortalize him as an ancient creature that once roamed the sea?”

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Female sperm

It has been possible in rare circumstances for a woman to give birth without being impregnated by a man. Parthenogenesis or asexual reproduction is more common among plants, insects, and animals like lizards. For human females to have a "virgin birth" requires them to be chimeras, developed from 2 different zygotes that merged in the womb. If the zygotes are different genders, resulting in an ovary on one side of her body and a testis on the other, a woman can fertilize herself. But now there is a new possibility on the horizon. Stem cell biologist Karim Nayernia of Newcastle University in the U.K. has created primitive sperm cells from female human embryonic stem cells. Irina Kerkis of the Butantan Institute in Saõ Paulo, Brazil, has reportedly made eggs from male mouse embryonic stem cells. This raises possibilities that gay and lesbian couples could have their own biological children. The bone marrow of one woman could be used to fertilize an egg from her partner and a man's skin cells could be used to make eggs, which could be fertilized by his partner’s sperm and implanted into the uterus of a surrogate mother. Although geneticists are skeptical that the reproductive cells will be able to divide properly, and the genetic makeup would mean that the offspring would be the same gender as the parents, the experiments hold the promise of future same-sex human reproduction.

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Petri meat

My Mom and I were just talking about the medical and scientific goal to increase the human lifespan by decades. She mentioned how it would affect the already skyrocketing costs of health care, and I pointed out that at some point the earth will no longer be able to support the expanding population. Physician and tissue engineer Mark Post of Maastricht University thinks the answer to environmental concerns is the production of meat in the laboratory as well as on the hoof. He has developed a technique to grow in vitro or cultured beef from a particular type of stem cell removed from cow necks. The result of billions of cells differentiating, merging, and putting on protein is 20,000 thin strips of fat-free cultured muscle tissue. Dr. Post plans to make them into patties, sprinkle them with salt and pepper, grill them, and serve them up in the coming weeks to make his point about the viability of these techniques. But our minds may not be as quick to change as the technology. Social scientist Neil Stephens of Cardiff University in Wales advises, “This is something very new. People need to wrestle with the idea of whether this is meat or not.”

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Scavenge, savage, scavenge

Ever since the griffon vulture (Gyps fulvus) became a protected species in France in the mid-1970s, farmers have complained that conservationists have upset the balance of nature. From 20 pairs, their numbers have increased to 500 pairs, and rather than scavenging carrion they have begun to attack live sheep, cows, and horses. Especially vulnerable are animals giving birth, since the birds – whose wingspans can reach 9.2' (2.8 m) – go after newborn and placenta. Farmers are prevented from shooting them and forced by EU regulations to burn the carcasses of any dead animals, so the vultures do not have enough to feed on. The controversy about the protection of the birds has reignited this month, due to an unfortunate incident that has gained international attention. A 52-year-old woman was hiking in the Pyrenees Mountains with 2 friends when she fell to her death from a 1,000' (300 m) cliff. By the time her body was recovered less than an hour later, she had been reduced to a skeleton by the vultures. "There were only bones, clothes and shoes left on the ground," reports Major Didier Pericou of the gendarmerie. Under stress because of the lack of food, the vultures have fanned out across Europe and become decidedly more aggressive, although the conservationists still insist that it is the birds that are under threat and not livestock. Frenchman M. Fourtine concludes, "Vultures are like ecologists. You need a few but not too many."

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Crime against culture

"This is one of the largest bulding[s] in Norther Belize. I am appalled! I was hoping that when I was driving up from the main San Juan road that it would not be this one but when I got closer I couldn't believe it when I saw all the trucks. This is an incredible destruction." – Dr. Allan Moore, Institute of Archaeology

On Sunday, the archaeologists of Belize discovered that one of the country's largest and most important Mayan monuments had been deliberately destroyed. The Noh Mul pyramid was the centerpiece of a ceremonial complex dating back to 350 B.C.E. Now all that remains is a central core which may well collapse once it is weakened by rain. A private construction company is responsible for demolishing the monument with bulldozers and backhoes, hauling away the limestone to use as gravel fill for a road project. Police are conducting an investigation and may file criminal charges, since any pre-Hispanic ruins are under government protection. The Belize community-action group Citizens Organised for Liberty Through Action called the construction company's action "an obscene example of disrespect for the environment and history."

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Loris illuminated

The insectivorous gray slender loris is endemic to the Eastern and Western Ghats, mountain ranges along the coasts of India. The sight of lorises in the forest is considered a bad omen among the native Kani people, but they are willing to round them up to satisfy the demands of photographers willing to pay substantial sums for a "managed" photo shoot with the charismatic primate. They use bright lights, scare tactics, and even tree-cutting methods to capture the nocturnal animals. They capture the lorises, hold them for several days in the village, set up the photo shoot, then re-release them far from the capture site. It's shameful that the illegal pet trade removes these sensitive creatures from their indigenous habitat, but the news that they often don't make it home after being caught on camera needs spreading. Conservation biologist Arun Kanagavel – who took the photograph above – cautions, "As far as possible handling these shy primates should be disallowed and instead loris-watching treks can be arranged to observe them in the wild and photograph them naturally."

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Ice twice

You may have seen footage on the news lately of lake ice being pushed into homes, but – like me – you may not have realized that there were 2 "ice tsunami" events in different locations over the weekend:

Lake Mille Lacs, 100 mi north of Minneapolis, Minnesota, U.S.A., Saturday, May 11th, breakfast-time. Winds as strong as 40 mph pushed a wall of ice onto the southeastern shorelines. The ice – 30' tall in some places –advanced on the homes and a resort on a 10-mile stretch of the lake (VIDEO HERE). Resident Darla Johnson describes, “You could hear it right through the doors, that’s what alerted us to all of it. And we turned around and you could just see it. It’s creepy because it starts coming towards you and you’re like ‘What is that!’”
Dauphin Lake, 200 mi northwest of Winnipeg, Manitoba, Canada. Friday, May 10th, dinner-time. Winds up to 35 mph pushed ice floes from the lake onto the shore of the Ochre Beach neighborhood and into the houses, completely destroying 6 and damaging another 14. “Bang! The ice came right through the living room,” says homeowner Dana Billows of the event which lasted a mere 15 minutes (PHOTOS AND VIDEOS HERE).

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An engineer's opinion

Cintec International in Newport, South Wales, U.K., has undertaken several projects to strengthen and restore ancient Egyptian monuments, including the Red Pyramid and the Bent Pyramid south of Cairo. Structural engineer Peter James, tasked with securing the Bent Pyramid's "cladding" (the smooth exterior facing), has arrived at a new theory of how it crumbled: thermal movement. With temperatures fluctuating from an average of 3°C (37⁰F) at night to an average of 40°C (104°F) during the day, the daily expansion and contraction of the limestone would explain the blocks grinding down, shifting, and detaching. "Multiply this endless movement by the number of days that the pyramid has been erected and you have the reason why all the outer casing has moved to the extremities, where it has buckled or displaced against blocks moving in the opposite direction and then fallen off." As construction techniques became more refined, the voids between the stones disappeared and the pyramids were less able to absorb the ebbs and flows. This would explain why the ancient Egyptians began building their tombs underground in the Valley of the Kings. But it also puts a stop to the long-held belief that the outer casing of the pyramids was looted for the limestone. Opportunists would have carried away the stone blocks only after they had fallen from the structure naturally.

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The opposite of déjà vu

"Unexpected Answer" by Belgian surrealist artist Rene Magritte (1898-1967).

Déjà vu, the strong sensation that a current occurrence has already been experienced, has a converse! Jamais vu is the eerie sense of undergoing something for the first time, despite knowing it has happened before. Both phenomena are recognized by the psychological and parapsychological communities, with explanations ranging from psychiatric disorder to reincarnation. But in 2006, cognitive neuropsychologist Chris Moulin of the University of Leeds put the phenomenon of jamais vu to the test. He induced it by means of "semantic satiation." In an experiment in which 92 subjects were asked to write common words including "door" 30 times in 60 seconds, 68% reported sensations of jamais vu. The words began to feel as if they were made up, misspelled, meaningless. Moulin explains that jamais vu can happen to musicians in the middle of playing a familiar passage, to people who visit a place they have been many times, and to those who stare into the face of a friend only to feel that they're looking at a stranger. "If you look at something for long enough the mind gets tired and it loses it's meaning."

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No breath, no pulse – but alive

Researchers at Boston Children’s Hospital have designed a liquid solution that can be injected directly into the bloodstream to quickly oxygenate the blood. Suspended in the solution are tiny, gas-filled microparticles, each surrounded by a membrane of fat and containing 3 to 4 times as much oxygen as a red blood cell. Cardiologist John Kheir explains, “This is a short-term oxygen substitute—a way to safely inject oxygen gas to support patients during a critical few minutes. Eventually, this could be stored in syringes on every code cart in a hospital, ambulance or transport helicopter to help stabilize patients who are having difficulty breathing.” The injection is able to keep a patient alive for up to 30 minutes after respiratory failure.
I remember the headlines generated in the summer of 2012 when the former Vice President of the U.S. had an assistive device implanted to help his failing heart. The New York Times explains, "His new mechanical pump, a partial artificial heart known as a ventricular assist device, leaves patients without a pulse because it pushes blood continuously instead of mimicking the heart’s own beat. Most pulse-less patients feel nothing unusual, but the devices do pose significant risks of infection. They are implanted as a last resort either for permanent use or as a bridge to transplant until a donor heart can be found." A year later, 5 patients are living with a new complete continuous-flow artificial heart designed by cardiologists Bud Frazier and Billy Cohn. Turbines replace the heart, which is removed, and keep blood circulating without mimicking the organ's pumping rhythm. Says Cohn, “I think we’re on the verge, right now, of solving the artificial-heart problem for good. All we had to do was get rid of the pulse.”

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Sunken continents in separate seas

ATLANTIC OCEAN: Japanese and Brazilian scientists have discovered a large amount of quartz sand and granite 8,000' (2400 m) below the surface and 900 mi (1500 km) off the coast of Rio de Janeiro. The rocks (PICTURED ABOVE AND HERE) are normally found on dry land, suggesting that a continent once existed in the region and sank tens of millions of years ago. “This could be Brazil’s Atlantis. We are almost certain, but we need to strengthen this hypothesis," says Roberto Ventura Santos, Director of the Geology Service of Brazil. He then adds, “We speak of Atlantis more in terms of symbolism. Obviously, we don’t expect to find a lost city in the middle of the Atlantic.”


INDIAN OCEAN: Norwegian scientists have found zircon in the sand on the beaches of Mauritius, located about 1,200 mi (2000 km) off the coast of Africa, east of Madagascar. The tiny island formed approximately 9 million years ago from cooling lava spewed by undersea volcanoes, but some of the mineral fragments are as much as 2 billion years old. This suggests that the zircon was part of a drowned microcontinent, pieces of which were brought to the surface by the lava. Conall Mac Niocaill, a geologist at the University of Oxford who was not involved in the study, commented, "The lines of evidence are, individually, only suggestive, but collectively they add up to a compelling story....We know more about the topography of Mars than we do about [that] of the world's ocean floor, so there may well be other dismembered continents out there waiting to be discovered."

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Breaking the ice

"We’ve sampled more than 100 different locations in the Ross Sea and my hands are cracked, chapped, and leather-like from long days working with the cold and salty water. The temperatures outside have dipped below zero degrees, dropping to -60°F with the wind chill, and the sea continues to ice over. Some of our equipment is beginning to freeze."

These are the words of doctoral student Cassandra Brooks of Stanford University, who spent 2 months this spring posted on the research vessel Nathaniel B. Palmer. She is quick to minimize her complaints in comparison to the epic Antarctic journeys of Robert F. Scott, Ernest Shackleton, and the other great explorers, and adds that the ship has the finest at-sea working and living conditions she's yet encountered. The Nathaniel B. Palmer is an icebreaker, with a hull that can smash through ice 10' thick. She describes the ice – including the pancake ice depicted above – in her narration of this mesmerizing time-lapse video.

 

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