Courtesy Mark RyanA new and troubling paper from the Committee on Understanding and Monitoring Abrupt Climate Change and its Impacts predicts possible and somewhat grim outcomes for some of Earth's natural systems from climate change that could rival the extinction event of the non-avian dinosaurs at the end of the Cretaceous Period 65 million years ago.
The abrupt impact could be coming faster than previously expected and would negatively affect human and physical climate systems as well. The document warns that the abruptness of the changes could be unanticipated and could find us unprepared to deal with them
Records of past climate preserved in tree rings, ice cores, and ocean sediments show that the atmosphere contains higher levels of carbon dioxide than it has in a very long time. Carbon emissions from human activity continue to add to this rising concentration. Other activities including deforestation and resource extraction place additional environmental pressures on our climate and other natural systems.
At the end of the Cretaceous, all species of non-avian dinosaurs, along with the megafauna of flying and swimming reptiles were wiped off the face of the Earth. Many dinosaur species showed signs of decline even before the Chicxlub asteroid delivered the final kibosh on their existence.
Dr. James W.C. White, a professor of Geological Sciences and of Environmental Studies at the University of Colorado at Boulder chaired the committee which included more than a dozen earth scientists and ocean researchers from universities in both Canada and the United States, and from the National Academy of Science.
A prepublication copy of the entire 201-page paper is available to read without charge on the National Academies Press page. You can also download it for free although it was a little tricky getting it to my computer.
Courtesy Majail0711Hey, it's Halloween. Do you have a seance to go to tonight after you finish your trick and treating?
And what's a good seance without a Ouija board? You know it's the quickest way to connect with the dead and find out those mysterious secrets that aren't accessible any other way.
It's been quite a while since I last touched a Ouija board. But I do remember being amazed how that little pad just skimmed across the board to give us answers to our questions. It's fun and mystical. And (SPOILER ALERT) it's all based on science.
The current issue of Smithsonian delves into the history and science behind the board. You can get all the details right here. Since the board's beginnings, the creators had insights into the ideometer effect. That's a fancy term for the automatic muscular movements that take place in our bodies without our conscious will or volition. It's like what happens to us when we cry during the sad part of a movie or flick away an annoying bug pestering us. People using a Ouija board are subtly moving the pointer around the board without realizing they are doing so.
Research conducted a couple years ago quantified what was happening. People were asked random fact-based questions that were challenging. Just hearing the questions and answering without a Ouija board, participants got about 50 percent correct, which was what researchers expected. But when participants were asked similar questions while seated at the Ouija board, that correct response rate jumped up to 65 percent.
The researchers account of the difference by people tapping into their non-conscious knowledge and using the ideometer effect to guide the Ouija board pointer across the board. And people actually do better answering questions on topics that they don't think they know the answer to than topics that they do.
So, if you do happen to find yourself sitting around a Ouija board tonight, be careful what you ask it. You might just get the answer to something you've been burying away in your mind for a long time!!!
Happy Halloween and feel free to share your observations here with other Buzz readers on the science of Ouija boards.
Courtesy cyclonebillThe arrival of fall each year brings leaves changing colors, apples ready for the picking and a host of long-distance races contested in more temperate conditions. And with those marathons and other distance tests come the pre-race rituals of "carbo loading," the practice of eating a high carbohydrate meal of pasta to fill a body up with extra energy.
But several elite athletes are now shaking up that conventional wisdom. They're saying that they're feeling better and performing more efficiently by focusing their pre-performance meals on the right kind of carbohydrates: gluten-free carbs.
Tennis champion Novak Djokovic, New Orleans Saints quarterback Drew Brees and the entire Garmin cycling team are now crediting gluten-free diets as helping them feel and perform better. Djokovic went gluten free in 2010 and has now climbed to become the No. 1-ranked player in men's pro tennis and he credits his new diet with giving him better focus, more endurance and avoiding injury.
However, all these benefits so far are anecdotal. There have been no research studies done on the impact of a gluten-free diet on athletic performance. But some nutritionists point out that gluten, evolutionary speaking, is a pretty new entry into the human diet, having only been around 10,000 years. Our digestive systems don't know how to deal with it, so we get no nutritional benefit from it. For most of us, our immune system handles the gluten in our digestive track, just like stray microbes, and works it into our waste. About six percent of the population is gluten sensitive and has to avoid these types of foods entirely.
Does this new information change your thoughts about "carbo loading?" Do you avoid gluten foods even if you're not sensitive to them? Share your thoughts with other Science Buzz readers.
Courtesy James Gathany/CDCHarry Potter has his cloak of invisibility. Chemical researchers think they're on the brink of finding substances to make us humans invisible to mosquitoes.
At the recent meeting of the American Chemical Society, information was presented on new compounds that can block human smells, the key that mosquitoes use to find their next meal. Current mosquito repellents are losing their effectiveness and chemical researchers think the newly discovered compounds can be even more effective.
How do they work? The chemicals interfere with the skeeters' ability to smell. Hundreds of chemicals make up the smells that come from human bodies. Mixing in different combinations, they make some people more attractive to mosquitoes than others. What they've found with these new chemicals, including 1-methylpiperzine, was that an arm sprayed with the chemicals and put into a cage full of mosquitoes was completely ignored. Mosquitoes didn't even land on the skin.
It will take a few years of testing to develop products using these new compounds. But if they live up to the hype, they could be a key tool in helping stop the 600,000 annual deaths worldwide caused by malaria spread through mosquito bites.
So don't ditch that can of Off just yet. You'll have at least a couple more summers of slapping and spraying the old-fashioned way.
Courtesy Mark RyanThe new Science Museum of Minnesota exhibit, Maya: Hidden Worlds Revealed has just opened and is a must-see for anyone interested in the ancient and mysterious civilization that once flourished and ruled in Central America. This wide-ranging exploration of the social, political, spiritual and cultural world of the Maya includes artifacts, displays, and hands-on interaction for museum visitors. In conjunction with this very special Science Museum of Minnesota exhibit, the SMM is partnering with the Maya Society of Minnesota to present several lectures at Hamline University during the exhibit's run this summer and into the winter.
I attended the first lecture in the series last Friday night. Archaeologist Jaime Awe
Courtesy Mark Ryan gave a brief overview of the early Maya worldview then talked about his work investigating some impressively large caves in western Belize near where he was born and raised. Inside the caves he and his research team have discovered pottery, torch sticks, writings, and ritualistic artifacts along with human footsteps and unburied skeletal remains, many of children.
Awe hypothesizes that the caves were used by the Maya (from the Classic Period) to make desperate ritualistic pleas by way of human sacrifices to the Maya rain deity. And evidence seems to back him up. Using carbon dating techniques and core analysis of stalactites from the caves, the time-frame of these cave rituals correlate with a period of severe drought in that region of Belize.
The Maya culture is a truly fascinating one. There are several more lectures and workshops to catch each month through next December, and the Maya exhibit at the museum runs through January 5, 2014. By the way, the museum's Omnitheater is also presenting the film Mystery of the Maya. which presents a very nice overview of the early Maya exploration and discoveries. I recommend you view the film first before going through the Maya: Hidden Worlds Revealed exhibit.
Tired of the constant din and bustle of modern life? Is the noise of screaming children or the neighbor's yapping miniature collie turning you into a nervous nelly? Maybe what you need is a place where you can go for some real top-notch peace and quiet.
That place could very well be the special anechoic chamber located at Orfield Laboratories right here in the Twin Cities. The chamber, which is hidden behind two vault doors, has 3.3-foot-thick fiberglass sound-deadening fiberglass acoustic wedges covering all of its flat surfaces, so instead of bouncing off the walls, ceiling, and floor as in a traditional room, any sounds are absorbed. I'm talking absorbed almost completely - the double-walled steel and concrete room is, in fact, 99.99 percent absorbent. That's a lot of quiet! Humans can't detect any sound registering below 0 dBA, and the Orfield chamber has a decibel rating of −9.4 dBA! The space is so soundproof it's listed in the Guinness Book of World as the "Quietest place on the planet."
Of course, there are some side effects to being thrust into utter silence. One is that the sounds inside your own body, your breathing, stomach gurgles, and of blood rushing through your veins become quite pronounced. "In the anechoic chamber, you become the sound," says lab president and founder Steven Orfield.
Be aware that it's not that easy being in a totally silent environment. The longest anyone has been able to withstand the sensory deprivation of the chamber is 45 minutes. And even short spells of dead silence can trigger hallucinations. The brain just doesn't like being deprived of sensory input.
Orfield's anechoic chamber has been used by several industries, including Harley-Davidson, Whirlpool, and airlines to test product sound levels, and by NASA to test the ability of astronauts to function in the extreme silence of space where, as they often say, no one can hear you scream.
Courtesy Mark RyanRemember when your cornea- that clear front cover on your eye - had only 5 layers of tissue: the corneal epithelium, Bowman's layer, the corneal stroma, Descemet's membrane, and the corneal endothelium? Well, those days are over. Scientists have just discovered a sixth layer, and christened it: Dua's layer.
It was identified by a team of researchers led by Harminder Dua, professor of Ophthalmology and Visual Sciences at the University of Nottingham so he got to put his name on it.
Although only 15 microns thick, Dua's layer is extremely durable and is located between the corneal stroma and Descemt's membrane near the back of the cornea. It's thought that several corneal diseases could be due to damage to or absence of the Dua's layer.
"From a clinical perspective, there are many diseases that affect the back of the cornea which clinicians across the world are already beginning to relate to the presence, absence or tear in this layer.“ --- Professor Harminder Dua
The discovery was published in the journal Ophthalmology and could greatly improve surgical success rates for corneal grafts and transplants.
Our great-ape cousins such as chimpanzees have feet that are very flexible in their middle region due to something called the midtarsal break that allows their feet to bend in the middle, enabling them to grasp at branches for easier climbing through trees. So when a chimp lifts his foot off the ground, it just flops about - there's nothing to hold the bones together. Most humans, on the other hand (or should I say foot?), have the same joint but have ligaments that stretch across it making the foot more rigid and stable for upright walking. Australopithecus sediba, a human ancestor that lived 2 million years ago, has a foot structure that is more ape-like than human, so somewhere along the line our feet evolved probably to accommodate our bipedalism.
The study was done by Jeremy DeSilva, a functional morphologist from Boston University, whose main interest is the evolution of the human foot and ankle. In this recent study, museum visitors were requested to walk barefoot across a mechanized carpet while DeSilva's team observed their gaits and the structure of their feet as they walked.
The surprising results showed that 8 percent of the nearly 400 participants possessed a flexible midtarsal break in their foot, and displayed a pressure signature in their footprint that looked like that found in the footprints of non-human primates. Perhaps more surprising is the fact that those subjects who had the unusual foot-joint structure weren't even aware of it until DeSilva revealed it to them.
The study was published in the American Journal of Physical Anthropology.
Courtesy Stevenfruitsmaak via Wikimedia CommonsWhen a cancer cell (a tumor) appears in a particular organ or area of a body, it somehow signals the body's immune system to back off and leave it alone. This allows the cancerous tumor to grow and eventually metastasize to the lymph nodes and other parts of the body. It's as if the cancer grants itself a sort of diplomatic immunity against the body's natural antibodies from interfering with its destructive undertakings.
Now, researchers have found a drug that switches off this "don't touch" warning and allows the cancer to be diminished or entirely destroyed. And it works for several types of cancers, including those affecting the brain, liver, colon, breast, ovary and prostate.
A protein called CD47 is present in human blood cells and prevents those cells from being attacked by the body's immune system. The protein attaches to the surface of the blood cells and signals to the immune system that the blood cells are "okay" and shouldn't be destroyed. About ten years ago, biologist Irving Weissman and researchers at Stanford University's School of Medicine noticed higher levels (up to 3x more) of the same "don't touch" protein were present in leukemia cells, a blood disorder. The surprised Weissman realized that the blood cancer was co-opting the body's own defense system to work against itself, thereby stopping any attacks on the cancer. This left the cancer unmolested and able to grow and spread. After further testing, Weissman and his colleagues subsequently discovered that CD47 levels in many other cancers were also higher than levels in normal cells.
"What we've shown is that CD47 isn't just important on leukemias and lymphomas, it's on every single human primary tumor that we tested.“
The Weissman lab has now developed a promising drug that switches off this "don't touch" signal in cancer cells giving the body's immune system the green light to go after them. The drug has been tested in the laboratory using petri dishes containing treated and untreated cancer molecules. Immune cells (macrophages) were present in each sample. In the untreated sample, the macrophages ignored the cancerous molecules, while they readily attacked those treated with the anti-CD47 drug. In later tests, a variety of human cancer tumors were placed into lab mice and left to grow for two weeks. After the tumors grabbed hold, they were treated with the anti-CD47 therapy and the tumors shrunk considerably or disappeared altogether.
"The microenvironment of a real tumor is quite a bit more complicated than the microenvironment of a transplanted tumor," Weissman said, "and it's possible that a real tumor has additional immune suppressing effects."
The biologist is confident that the research will eventually move into human clinical trials within the next two years.
Courtesy rijksbandradio (original image) via Flckr; graphic by author.By now most readers are aware of the double helix, the two intertwined ribbons of genetic information that make up our DNA.
Now researchers at University of Cambridge have announced the discovery of a quadruple helix in the human genome. The four-stranded genetic ribbons are termed G-quadruplexes because they contain high levels of the nucleotide guanine (the other 3 nucleotides are adenine, thymine, and cytosine – together they make up the G, A, T, and C elements of DNA; uracil (U) replaces thymine in RNA). G-quadruplexes mainly appear at the moment of cell replication, when cells divide and multiply. Researchers think this indicates that G-quadruplexes are an essential part of the replication process. The upsurge of G-quadrupleexes was detected using fluorescent biomarkers. The discovery could open up new avenues in the treatment of cancer
"The research indicates that quadruplexes are more likely to occur in genes of cells that are rapidly dividing, such as cancer cells,” said Shankar Balasubramanian, the study’s lead researcher. “For us, it strongly supports a new paradigm to be investigated -- using these four-stranded structures as targets for personalised treatments in the future."
Balasubramanian, a professor at the Department of Chemistry and Cambridge Research Institute, thinks synthetic molecules could one day be used to corral the G-quadruplexes and hinder the out-of-control cell division often prevalent in cancerous cells. In fact, the research team has already been successful in slowing down the replication process by using such molecules. During their experiments, when cell division was blocked, the number of G-quadruplexes decreased.
The research was published in Nature Chemistry. The 'quadruple helix' discovery comes 60 years after the discovery of the double helix in 1953, also at the University of Cambridge.