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In 1897, Indiana almost passed a bill to change the value of pi. An amateur mathematician decided he had proof that pi was not 3.14, but actually 3.2, so he convinced the state to take on the bill. It passed the House unanimously, made it through a Senate committee, and likely would’ve been approved if a professor from Purdue hadn’t been in town. After hearing the news, he went to the state- house, watched the debate, decided to intervene, and eventually convinced the Senate that the theory was nonsense. Source Source 2
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In recent years, astronauts have reported their vision changing as a result of long-duration spaceflight. Pre- and post-flight studies of astronauts’ eyes showed flattening along the backside of the eyeball, and scientists hypothesized that the redistribution of body fluids that occurs in microgravity could be reshaping astronauts’ eyes by increasing the intracranial pressure in their skulls.
A new study tested this hypothesis with the first-ever measurements of intracranial pressure during microgravity flights and during extended microgravity simulation (a.k.a. bedrest with one’s head pointed downward). The authors found that humans here on Earth experience substantial changes in intracranial pressure depending on our posture – while upright we experience much lower intracranial pressure than we do when we’re lying flat. In both microgravity flights and simulation, patients had intracranial pressures that were higher than earthbound upright values but lower than what is experienced when lying flat on Earth.
Since we humans on Earth spend about 2/3rds of our time upright and 1/3rd prone, our bodies are accustomed to regular variations in intracranial pressure. In space, astronauts don’t receive that regular unloading of intracranial pressure we have when we’re upright. So now researchers suggest that it is the lack of daily variation in intracranial pressure that is the culprit behind astronauts’ vision changes – not the absolute value of the pressure itself. (Image credit: NASA; N. Alperin et al.; research credit: J. Lawley et al.)
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Harvard team claims it has finally created metallic hydrogen, a huge breakthrough–if true. https://t.co/YjyDIdkm57 http://pic.twitter.com/GoBVyfeBgG
— Corey S. Powell (@coreyspowell) January 26, 2017 -
Fly from Los Angeles to Sydney in Under Four Hours on this Sleek Supersonic Jet
Charles Bombardier’s newest aircraft concept is designed to shuttle hundreds of passengers long distances in a fraction of the time it takes a modern commercial airliner.
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WORLDS MOST FEARED US Air Force F-22 Aircraft ready to make the Russians jealous
A great demonstration of the US Air Force F-22 Aircraft which is considered the worst nightmare for the S-400 missile air defense system. TYNDALL AIR FORCE BASE, Fla. - Four Tyndall F-22 Raptors and approximately 60 Airmen assigned to the 325 Fighter Wing arrived at Spangdahlem Air Base, Germany, today to train with allied air forces and U.S. services through mid-September.
This first-ever F-22 training deployment to Europe is funded by the European Reassurance Initiative, and provides support to bolster the security of our NATO allies and partners in Europe.
“This inaugural Raptor training deployment is the perfect opportunity for these advanced aircraft to train alongside other U.S. Air Force aircraft, joint partners and NATO allies,” said General Frank Gorenc, U.S. Air Forces in Europe and Air Forces Africa commander.
The training will prove that 5th generation fighters can deploy successfully to European bases and other NATO installations while also affording the chance for familiarization flight training within the European theater. It will also give them the chance to conduct combat air training with different aircraft like U.S. F-15 Eagles and F-16 Fighting Falcons.
“It’s important we test our infrastructure, aircraft capabilities and the talented Airmen and allies who will host 5th generation aircraft in Europe,” said Gorenc. “This deployment advances our airpower evolution and demonstrates our resolve and commitment to European safety and security.”
Video Description Credit: Airman 1st Class Sergio Gamboa
Video Credit: Airman 1st Class Nicolas Myers
Video Thumbnail credit: Rob Shenk from Great Falls, VA, USA This file is licensed under the Creative Commons Attribution-Share Alike 2.0 Generic license. Licence link: https://creativecommons.org/licenses/… This Photo Modified by ArmedForcesUpdate
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Cyber security and authentication have been under attack in recent months as, seemingly every other day, a new report of hackers gaining access to private or sensitive information comes to light. Just recently, more than 500 million passwords were stolen when Yahoo revealed its security was compromised.
Securing systems has gone beyond simply coming up with a clever password that could prevent nefarious computer experts from hacking into your Facebook account. The more sophisticated the system, or the more critical, private information that system holds, the more advanced the identification system protecting it becomes.
Fingerprint scans and iris identification are just two types of authentication methods, once thought of as science fiction, that are in wide use by the most secure systems. But fingerprints can be stolen and iris scans can be replicated. Nothing has proven foolproof from being subject to computer hackers.
“The principal argument for behavioral, biometric authentication is that standard modes of authentication, like a password, authenticates you once before you access the service,” said Abdul Serwadda a cybersecurity expert and assistant professor in the Department of Computer Science at Texas Tech University.
“Now, once you’ve accessed the service, there is no other way for the system to still know it is you. The system is blind as to who is using the service. So the area of behavioral authentication looks at other user-identifying patterns that can keep the system aware of the person who is using it. Through such patterns, the system can keep track of some confidence metric about who might be using it and immediately prompt for reentry of the password whenever the confidence metric falls below a certain threshold.”
One of those patterns that is growing in popularity within the research community is the use of brain waves obtained from an electroencephalogram, or EEG. Several research groups around the country have recently showcased systems which use EEG to authenticate users with very high accuracy.
However, those brain waves can tell more about a person than just his or her identity. It could reveal medical, behavioral or emotional aspects of a person that, if brought to light, could be embarrassing or damaging to that person. And with EEG devices becoming much more affordable, accurate and portable and applications being designed that allows people to more readily read an EEG scan, the likelihood of that happening is dangerously high.
“The EEG has become a commodity application. For $100 you can buy an EEG device that fits on your head just like a pair of headphones,” Serwadda said. “Now there are apps on the market, brain-sensing apps where you can buy the gadget, download the app on your phone and begin to interact with the app using your brain signals. That led us to think; now we have these brain signals that were traditionally accessed only by doctors being handled by regular people. Now anyone who can write an app can get access to users’ brain signals and try to manipulate them to discover what is going on.”
That’s where Serwadda and graduate student Richard Matovu focused their attention: attempting to see if certain traits could be gleaned from a person’s brain waves. They presented their findings recently to the Institute of Electrical and Electronics Engineers (IEEE) International Conference on Biometrics.
Brain waves and cybersecurity
Serwadda said the technology is still evolving in terms of being able to use a person’s brain waves for authentication purposes. But it is a heavily researched field that has drawn the attention of several federal organizations. The National Science Foundation (NSF), funds a three-year project on which Serwadda and others from Syracuse University and the University of Alabama-Birmingham are exploring how several behavioral modalities, including EEG brain patterns, could be leveraged to augment traditional user authentication mechanisms.
“There are no installations yet, but a lot of research is going on to see if EEG patterns could be incorporated into standard behavioral authentication procedures,” Serwadda said.
Assuming a system uses EEG as the modality for user authentication, typically for such a system, all variables have been optimized to maximize authentication accuracy. A selection of such variables would include:
- The features used to build user templates.
- The signal frequency ranges from which features are extracted
- The regions of the brain on which the electrodes are placed, among other variables.
Under this assumption of a finely tuned authentication system, Serwadda and his colleagues tackled the following questions:
- If a malicious entity were to somehow access templates from this authentication-optimized system, would he or she be able to exploit these templates to infer non-authentication-centric information about the users with high accuracy?
- In the event that such inferences are possible, which attributes of template design could reduce or increase the threat?
Turns out, they indeed found EEG authentication systems to give away non-authentication-centric information. Using an authentication system from UC-Berkeley and a variant of another from a team at Binghamton University and the University of Buffalo, Serwadda and Matovu tested their hypothesis, using alcoholism as the sensitive private information which an adversary might want to infer from EEG authentication templates.
In a study involving 25 formally diagnosed alcoholics and 25 non-alcoholic subjects, the lowest error rate obtained when identifying alcoholics was 25 percent, meaning a classification accuracy of approximately 75 percent.
When they tweaked the system and changed several variables, they found that the ability to detect alcoholic behavior could be tremendously reduced at the cost of slightly reducing the performance of the EEG authentication system.
Motivation for discovery
Serwadda’s motivation for proving brain waves could be used to reveal potentially harmful personal information wasn’t to improve the methods for obtaining that information. It’s to prevent it.
To illustrate, he gives an analogy using fingerprint identification at an airport. Fingerprint scans read ridges and valleys on the finger to determine a person’s unique identity, and that’s it.
In a hypothetical scenario where such systems could only function accurately if the user’s finger was pricked and some blood drawn from it, this would be problematic because the blood drawn by the prick could be used to infer things other than the user’s identity, such as whether a person suffers from certain diseases, such as diabetes.
Given the amount of extra information that EEG authentication systems are able glean about the user, current EEG systems could be likened to the hypothetical fingerprint reader that pricks the user’s finger. Serwadda wants to drive research that develops EEG authentication systems that perform the intended purpose while revealing minimal information about traits other than the user’s identity in authentication terms.
Currently, in the vast majority of studies on the EEG authentication problem, researchers primarily seek to outdo each other in terms of the system error rates. They work with the central objective of designing a system having error rates which are much lower than the state-of-the-art. Whenever a research group develops or publishes an EEG authentication system that attains the lowest error rates, such a system is immediately installed as the reference point.
A critical question that has not seen much attention up to this point is how certain design attributes of these systems, in other words the kinds of features used to formulate the user template, might relate to their potential to leak sensitive personal information. If, for example, a system with the lowest authentication error rates comes with the added baggage of leaking a significantly higher amount of private information, then such a system might, in practice, not be as useful as its low error rates suggest. Users would only accept, and get the full utility of the system, if the potential privacy breaches associated with the system are well understood and appropriate mitigations undertaken.
But, Serwadda said, while the EEG is still being studied, the next wave of invention is already beginning.
“In light of the privacy challenges seen with the EEG, it is noteworthy that the next wave of technology after the EEG is already being developed,” Serwadda said. “One of those technologies is functional near-infrared spectroscopy (fNIRS), which has a much higher signal-to-noise ratio than an EEG. It gives a more accurate picture of brain activity given its ability to focus on a particular region of the brain.”
The good news, for now, is fNIRS technology is still quite expensive; however there is every likelihood that the prices will drop over time, potentially leading to a civilian application to this technology. Thanks to the efforts of researchers like Serwadda, minimizing the leakage of sensitive personal information through these technologies is beginning to gain attention in the research community.
“The basic idea behind this research is to motivate a direction of research which selects design parameters in such a way that we not only care about recognizing users very accurately but also care about minimizing the amount of sensitive personal information it can read,” Serwadda said.
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In 1967, just a few months after Star Trek debuted on television, the show’s creator - Gene Roddenberry - used this very letterhead for all business correspondence.
Gene Roddenberry, 1967 | Submitted by Dale Macy
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the new car electric car to rival Tesla ? http://pic.twitter.com/91kmNidAeK
— Billionaires (@BiIlionaires) January 4, 2017 -
Battery Cell Production Begins at the Gigafactory https://t.co/xrFl4tChBx
— Tesla (@TeslaMotors) January 4, 2017 -
DOLLOCARIS, A PREDATOR OF THE JURASSIC WAS ALL EYES.
Vision has revolutionized the way animals explore their environment and interact with each other and rapidly became a major driving force in animal evolution. However, direct evidence of how ancient animals could perceive their environment is extremely difficult to obtain because internal eye structures are almost never fossilized.
Today, paleontologists reconstruct with unprecedented resolution the three-dimensional structure of the huge compound eye of a 160-million-year-old thylacocephalan arthropod from the La Voulte exceptional fossil biota in South East France. The study was published 19 January in Nature Communications.
This arthropod called Dollocaris ingens had about 18,000 lenses on each eye, which is a record among extinct and extant arthropods and is surpassed only by modern dragonflies. Combined information about its eyes, internal organs and gut contents obtained by X-ray microtomography lead to the conclusion that this thylacocephalan arthropod was a visual hunter probably adapted to illuminated environments, thus contradicting the hypothesis that La Voulte was a deep-water environment.
- Eye structure of Dollocaris ingens.
As a group, the Thylacocephala survived to the Upper Cretaceous. Beyond this, there remains much uncertainty concerning fundamental aspects of the thylacocephalan anatomy, mode of life, and relationship to the Crustacea, with whom they have always been cautiously aligned.
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X-Rayed Skeleton
You can also follow BPoD on Twitter and FacebookA web of chromatin grows along the DNA inside the nucleus of our cells – it’s represented in bright colours in this mouse nerve cell. The skeleton-like chromatin changes as stem cells develop into nerve cells, shaping the life inside by controlling access to the DNA. Understandably, scientists want to take a close look at chromatin, but many have found it too sensitive to lab techniques. Here, x-rays fired into the nucleus from many angles, gently highlight two different types of chromatin in 3D without causing any damage. One form of chromatin (blue green) is surrounded and linked to heterochromatin (red-yellow), a more compact form which affects which genes can be switched on or off, playing major roles in development. Now the x-ray technique can be applied to different types of cell (even those with genetic mutations), and heterochromatin watched as is moves and shifts, altering life as it goes.
Written by John Ankers
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1. Gravitational waves are real. More than 100 years after Einstein first predicted them, researchers finally detected the elusive ripples in space time this year. We’ve now seen three gravitational wave events in total.
2. Sloths almost die every time they poop, and it looks agonising.
3. It’s possible to live for more than a year without a heart in your body.
4. It’s also possible to live a normal life without 90 percent of your brain.
5. There are strange, metallic sounds coming from the Mariana trench, the deepest point on Earth’s surface. Scientists currently think the noise is a new kind of baleen whale call.
6. A revolutionary new type of nuclear fusion machine being trialled in Germany really works, and could be the key to clean, unlimited energy.
7. There’s an Earth-like planet just 4.2 light-years away in the Alpha Centauri star system - and scientists are already planning a mission to visit it.
8. Earth has a second mini-moon orbiting it, known as a ‘quasi-satellite’. It’s called 2016 HO3.
9. There might be a ninth planet in our Solar System (no, Pluto doesn’t count).
10. The first written record demonstrating the laws of friction has been hiding inside Leonardo da Vinci’s “irrelevant scribbles” for the past 500 years.
11. Zika virus can be spread sexually, and it really does cause microcephaly in babies.
12. Crows have big ears, and they’re kinda terrifying.
13. The largest known prime number is 274,207,281– 1, which is a ridiculous 22 million digits in length. It’s 5 million digits longer than the second largest prime.
14. The North Pole is slowly moving towards London, due to the planet’s shifting water content.
15. Earth lost enough sea ice this year to cover the entire land mass of India.
16. Artificial intelligence can beat humans at Go.
17. Tardigrades are so indestructible because they have an in-built toolkit to protect their DNA from damage. These tiny creatures can survive being frozen for decades, can bounce back from total desiccation, and can even handle the harsh radiation of space.
18. There are two liquid states of water.
19. Pear-shaped atomic nuclei exist, and they make time travel seem pretty damn impossible.
20. Dinosaurs had glorious tail feathers, and they were floppy.
21. One third of the planet can no longer see the Milky Way from where they live.
22. There’s a giant, 1.5-billion-cubic-metre (54-billion-cubic-foot) field of precious helium gas in Tanzania.
23. The ‘impossible’ EM Drive is the propulsion system that just won’t quit. NASA says it really does seem to produce thrust - but they still have no idea how. We’ll save that mystery for 2017.
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Actually, the Big Bang theory does not postulate that the universe was all contained in a single point. The theory only postuates that early in the universe, it was extremely compact, hot, and expanding rapidly. It makes no attempt to extrapolate to zero time, because the math fails, and every professional in the business thinks that a failure in the math means that there is some new physics principle at work that will alter the equations for those super-early moments.
That doesn’t stop people from ignoring the mathematical failure and postulating what did happen. Indeed, that is the way physics progresses. But the honest answer is that for the very early time, when the universe was no more than a Planck length in size, our current physics theory tells us nothing.
My own favorite speculation is the one you mention in your question, that time did not exist prior to the Big Bang. But if time didn’t exist, then what does it mean for time to “be created”. That requires movement of time. So many physicists think that when the proper new physics is added it, we will find that the universe existed before the Big Bang, and that what we are seeing is some sort of a “bounce”. But we don’t know the true physics for such super dense material, so we can’t really say much more.
As I said, I enjoy more the idea that time just started at the Big Bang. But this is not physics; it is playful speculation.
Richard Muller, Prof Physics, UCBerkeley, auth “Now -The Physics of Time- (to be published 2016) -
Aging Is Reversible--at Least in Human Cells and Live Mice:
New research suggests it is possible to slow or even reverse aging, at least in mice, by undoing changes in gene activity—the same kinds of changes that are caused by decades of life in humans.
By tweaking genes that turn adult cells back into embryoniclike ones, researchers at the Salk Institute for Biological Studies reversed the aging of mouse and human cells in vitro, extended the life of a mouse with an accelerated-aging condition and successfully promoted recovery from an injury in a middle-aged mouse, according to a study published Thursday in Cell.
The study adds weight to the scientific argument that aging is largely a process of so-called epigenetic changes, alterations that make genes more active or less so. Over the course of life cell-activity regulators get added to or removed from genes. In humans those changes can be caused by smoking, pollution or other environmental factors—which dial the genes’ activities up or down. As these changes accumulate, our muscles weaken, our minds slow down and we become more vulnerable to diseases.
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Sorry For Overreacting!
High-speed footage of a Thermite reaction producing molten iron. Thermite is a mixture of powdered aluminum and iron oxide which reacts when ignited, producing iron and aluminum oxide in an exothermic reduction-oxidation (redox) reaction.
SEE MORE ‘EXOTHERMIC REACTION’ VIDEOS
Molten iron is seen dripping out of the bottom of the flower pot as the reaction progresses. The reaction has a number of commercial uses that make use of its high temperature, including welding steel railroad tracks and cutting through metals in situ.
The thermite reaction was discovered in 1893 and patented in 1895 by German chemist named Hans Goldschmidt. Consequently, the reaction is sometimes called the “Goldschmidt reaction” or “Goldschmidt process”. Goldschmidt was originally interested in producing very pure metals by avoiding the use of carbon in smelting, but he soon discovered the value of thermite in welding.
Filmed at 250 frames per second (slowed down 10 times).
Video above © SPL / Science Source
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Nobody should be allowed to burn the American flag - if they do, there must be consequences - perhaps loss of citizenship or year in jail!
— Donald J. Trump (@realDonaldTrump) November 29, 2016 -
If you’re in a vehicle traveling at the speed of light, what happens when you turn on the head lights?
— Eclihpse ? (@ItsEclihpse) November 23, 2016 -
When you consider the size of the universe, or even the size of our galaxy, “the speed of light” is actually painfully slow.
— Shower Thoughts (@TheWeirdWorld) November 23, 2016 -
The speed of light might have outpaced gravity in the early days of the Universe. https://t.co/ubpnmmNdKF http://pic.twitter.com/KLyDK4YBf7
— Science Channel (@ScienceChannel) November 24, 2016 -
Customized e-cigarette explodes in man’s pants, again https://t.co/rprVAh7jaO http://pic.twitter.com/YRdoEdGh0N
— Gizmodo (@Gizmodo) November 25, 2016
How human brains do language: one system, two channels
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