Wednesday, April 27, 2016

Influence of Jupiter in the history of earth

In other planetary systems, we see evidence that giant planets like Jupiter can migrate from where they originally formed, spiraling inward to an orbit closer to their stars. When these giants wander toward their stars, any small, rocky planets that stand in the way can be swallowed up or, due to the giants’ strong gravity, flung out of the star system altogether.

But if Jupiter-like planets remain distant from their stars, they can serve as the gatekeepers to their planetary systems. They protect their fellow planets on inner orbits, allowing them to maintain nearly circular orbits that provide stable climates over extended periods of time. Long, elliptical orbits cause extreme climate shifts for an Earth-like planet, possibly preventing any sort of sustained life from evolving.

In our solar system, Jupiter can eat up any asteroid or comet that ventures near, earning the nickname “vacuum cleaner of the solar system.” The asteroid belt in between the orbits of Mars and Jupiter is another example of the gas giant’s influence. Its gravity likely prevented the asteroids from combining into a planet.

Jupiter can also radically alter the orbits of small bodies that stray close, hurling them on long orbits that take hundreds or even thousands of years for those bodies to return. We think this is how comets got the extreme orbits that carry them to the far-flung reaches of the solar system. They spend most of their time out there, forming a cometary collection called the Oort cloud, which may extend as far as halfway to the nearest star.

While Jupiter often protects Earth and the other inner planets by deflecting comets and asteroids, sometimes it sends objects on a collision course straight toward the inner planets. Earlier in the solar system’s history, when there were more objects flying around, the increased amount of impacts would have brought to Earth water and other ingredients for life. Of course, other collisions would have been disastrous, such as the impact that likely led to the extinction of the dinosaurs 65 million years ago.

Studies show, Living in a green neighborhood reduces chronic diseases

A new study of a quarter-million Miami-Dade County Medicare beneficiaries showed that higher levels of neighborhood greenness, including trees, grass and other vegetation, were linked to a significant reduction in the rate of chronic illnesses, particularly in low-to-middle income neighborhoods. Led by researchers at the University of Miami Department of Public Health Sciences at the Miller School of Medicine, and the School of Architecture, the study showed that higher greenness was linked to significantly lower rates of diabetes, hypertension and high cholesterol, as well as fewer chronic health conditions.
The findings, published online April 6 by the American Journal of Preventive Medicine, are based on 2010 -- 2011 health data reported for approximately 250,000 Miami-Dade Medicare beneficiaries over age 65, and a measure of vegetative presence based on NASA satellite imagery. The study was the first of its kind to examine block-level greenness and its relationship to health outcomes in older adults, and the first to measure the impact of greenness on specific cardio-metabolic diseases.
"This study builds on our research group's earlier analyses showing block level impacts of mixed-use and supportive building features on adults and children," said lead study author Scott Brown, Ph.D., research assistant professor of public health sciences. Brown was a co-principal investigator on the study with Elizabeth Plater-Zyberk, M.Arch., a Malcolm Matheson Distinguished Professor in Architecture. Plater-Zyberk, who was responsible for the rewrite of the City of Miami's zoning code in 2010, said the study results "give impetus to public agencies and property owners to plant and maintain a verdant public landscape."
Study findings revealed that higher levels of greenness on the blocks where the study's Medicare recipients reside, is associated with a significantly lower chronic disease risk for the residents of high greenness blocks, including a 14 percent risk reduction for diabetes, a 13 percent reduction for hypertension and a 10 percent reduction for lipid disorders.
"Going from a low to a high level of greenness at the block level is associated with 49 fewer chronic health conditions per 1,000 residents, which is approximately equivalent to a reduction in the biomedical aging of the study population by three years," said Brown.
Jack Kardys, Director of the Miami-Dade County Department of Parks, Recreation and Open Spaces, participated in data interpretation along with Miami-Dade County Parks' Chief of Planning, Research, and Design Excellence, Maria Nardi. Kardys said the study findings "illuminate the vital role of parks and greens to health and well-being, and point to the critical need for a holistic approach in planning that draws on research."
The study findings suggest extensive potential for park, open space, and streetscape design in South Florida and the United States to consider health impacts in strategic planning. Funded by the U.S. Department of Housing and Urban Development (HUD) Office of Policy Development and Research and the Health Foundation of South Florida, the research adds to a growing body of evidence that exposure to higher levels of greenness is associated with better health outcomes, by reducing stress, air pollution, humidity and heat island impacts, and encouraging physical activity, social interaction and community cohesion.
From a design standpoint, study co-author Joanna Lombard, M.Arch., professor of architecture, noted that the goals of the County's Parks and Open Spaces Masterplan already call for residents to have access to greenspace from the minute they walk outside of their homes, through tree-lined streets, as well as greens, parks, and open spaces within a 5 to 10 minute walk of their home, all of which have been shown to be linked to better health outcomes. "There's so much suffering involved in the time, money and energy spent on disease burden in the U.S., which we realize that we can, to some extent, ameliorate through healthy community design," said Lombard. "We collectively need to be attentive to the health impacts of the built environment. The associated harms are evident, and most importantly going forward, the potential benefits are significant."
In examining the results by income level and by race, the research showed that the health benefits of greenness were proportionately stronger among all racial and ethnic groups in lower income neighborhoods. Brown said this aspect of the findings suggests that incorporating more green -- trees, parks and open spaces -- in low income neighborhoods could also address issues of health disparities, which have been recently highlighted in research journals and the national media.
José Szapocznik, Ph.D., professor and chair of public health sciences, and founder of the University of Miami Built Environment, Behavior, and Health Research Group, pointed out that augmenting greenness, particularly in warm climates, potentially contributes to the effectiveness of other aspects of walkability. "Providing a green feature," said Szapocznik, "has been associated with safety, increased time outdoors, physical activity, and social interaction, and may potentially reduce disease burdens at the population level and enhance residents' quality of life."

Thursday, April 21, 2016

What would the results be if the entire history of earth were to be compressed into a single day?

WEIRDNESS WARNING!!!!!!!!!!!!!!!!!!
 Anyway, we shall find that the earth was formed at midnight(duh). It is not until 4 am that life first appears consisting of simple single cell organisms. And then around 1 pm one cell engulfs another forming a Symbiotic relationship or Eukaryotic cells. Multi cellular organisms appear when these   Eukaryotic cells form colonies until 6:30 pm. Plants finally appear around 8:30 pm in the bottom of the sea. 10 minutes before 9 pm sea animals suddenly start to evolve. with barely 3 minutes before 10 pm, plants appear on land followed by animals twenty seven  minutes later, winged insects appear. Soon reptiles start to dominate the earth until a mass extinction occurs at roughly 11 pm Giving a chance for dinosaurs to Rule. But at 11:41 pm they too Disappear due to a meteor impact. The age of mammals begins  in the last few minutes as monkeys split in the evolutionary process. Humans finally appear a minute and a 17 seconds left and all the history we learn in social studies  fits in barely a few seconds. Brain exploded? here is a small timeline of the above paragraph.


  • Midnight  : Earth forms
  • 4 am : Single cell organisms appear
  • 1 pm : Eukaryotic cells form after one cell engulfs another
  • 6:30  pm : Eukaryotic cells form colonies and multi cellular life is first found
  • 8:30 pm : Sea plants and sea animals appear.
  • 9:57 pm: plants appear on land 
  • 10:24 pm : Winged insects appear briefly followed by animals 
  • 11 pm : mass extinction wipes out most of the dominating reptiles
  • 11:47 pm : dinosaurs wiped out
  • 11:58:43 pm : Humans appear
  • second midnight: present
                            Image result for history of earth planet

Monday, April 18, 2016

What is the history of "How the speed of light is calculated" ?

In the early 17th century, many people believed that speed of light is infinite. Galileo Galilei disagreed. In 1638, he tried an experiment in which he and another person each took a shutter lantern and walked miles apart. The rule was, as soon as one of them flashes lantern, the other one will flash back. Then Galileo just divided the distance by time. He found that speed of light was atleast 10 times greater than the speed of sound(3.4 km/s). But he accidentally calculated the  time taken to react to react by human body.

In 1675, the Danish astronomer Ole Roemer noticed, while observing Jupiter's moons, that the times of the eclipses of the moons of Jupiter seemed to depend on the relative positions of Jupiter and Earth. If Earth was close to Jupiter, the orbits of its moons appeared to speed up. If Earth was far from Jupiter, they seemed to slow down. Reasoning that the moons orbital velocities should not be affected by their separation, he deduced that the apparent change must be due to the extra time for light to travel when Earth was more distant from Jupiter. Using the commonly accepted value for the diameter of the Earth's orbit, he came to the conclusion that light must have traveled at 300,000 Km/s.

In 1728 James Bradley, an English physicist, estimated the speed of light in vacuum to be around 301,000 km/s. He used stellar aberration to calculate the speed of light. Stellar aberration causes the apparent position of stars to change due to the motion of Earth around the sun. Stellar aberration is approximately the ratio of the speed that the earth orbits the sun to the speed of light. He knew the speed of Earth around the sun and he could also measure this stellar aberration angle. These two facts enabled him to calculate the speed of light in vacuum.

In 1849, a French physicist, Hippolyte Louis Fizeau, shone a light between the teeth of a rapidly rotating toothed wheel. A mirror more than 5 miles away reflected the beam back through the same gap between the teeth of the wheel. There were over a hundred teeth in the wheel. The wheel rotated at hundreds of times a second; therefore a fraction of a second was easy to measure. By varying the speed of the wheel, it was possible to determine at what speed the wheel was spinning too fast for the light to pass through the gap between the teeth, to the remote mirror, and then back through the same gap. He knew how far the light traveled and the time it took. By dividing that distance by the time, he got the speed of light. Fizeau measured the speed of light to be 313,300 Km/s.

In 1862, another French physicist, Leon Foucault, used a similar method to Fizeau. He shone a light to a rotating mirror, then it bounced back to a remote fixed mirror and then back to the first rotating mirror. But because the first mirror was rotating, the light from the rotating mirror finally bounced back at an angle slightly different from the angle it initially hit the mirror with. By measuring this angle, it was possible to measure the speed of the light. Foucault continually increased the accuracy of this method over the years. His final measurement determined that light traveled at299,796 Km/s.

As of now, astronauts have attached a mirror to a rock on the moon. Scientists on earth can aim a laser at this mirror and measure the travel time of the laser pulse(about 2.5 s) for the round trip. The British National Physical Laboratory considered the speed of light to be 299792.4590 ± 0.0008 km/sec and US National Bureau of Standards considered it to be 299792.4574 ± 0.0011 km/sec.
299,792.458 km/s is the adopted value for speed of light at the General Conference of Weights And Measures, 1983 Oct 21.
Since 1983, the meter has been internationally defined as the length of the path traveled by light in vacuum during a time interval of 1/299792458 of a second.

Friday, April 15, 2016

Thousands of radioactive boars are tearing through Fukushima, and no one knows how to stop them

From mutated insects and broken-down rescue robots, to cobweb-infested schools that haven’t been touched in years, the Fukushima evacuation zone - the site of one of the worst disasters of the 21st century - is showing no signs of regaining even a semblance of habitability... for humans, at least.
Wild boars are reportedly thriving in the evacuated areas around the Fukushima Daiichi Nuclear Power Plant, which experienced multiple meltdowns following an earthquake-triggered tsunami back in 2011. And now they’re tearing through nearby farmlands, causing more than US$900,000 (¥98 million) in crop damage for local farmers.
         
            How did things get so bad? Well, under normal circumstances, this boar population would be kept under control by local hunters, with The Japan Timescalling pork - including wild boar meat - "the nation’s most popular meat".
       
           But the problem is these wild boars have been contaminated with caesium-137 - a radioactive substance with a half-life of 30 years - from eating plants and small animals around the exclusion zone, and now the hunters won’t go near them.

    "Wild boar, along with raccoon, have been taking advantage of the evacuation zone, entering vacant houses in areas damaged by the [disaster], and using them as breeding places or burrows," assistant ecology professor Okuda Keitokunin at the Fukushima University Environmental Radioactivity Institutetold the local press.

           Now reproducing with abandon in the exclusion zones, the wild boar population has increased 300 percent since the disaster, from around 3,000 to 13,000, and they’re spilling out into the nearby farms to tear up and trample the crops.
And local authorities are running out of ideas for how to contain the rampaging force of radioactive boars, as Travis Andrews at The Washington Post reports:
"These animals are unfit for human consumption, which presents another problem: hunters can attempt to reduce the population, but they have to do something with the carcasses. According to Texas A&M wildlife and fisheries professor Billy Higginbotham, the average size of a male hog is around 200 pounds (90 kg).


                    Considering this average, if 13,000 are killed, hunters have around 2,600,000 pounds (1,179,340 kg) of potentially dangerous flesh requiring disposal."

The hunters have been dumping the radioactive boar carcasses in three designated mass graves in the nearby city of Nihonmatsu, but they’re only big enough to hold about 600 of these sizeable creatures, and they’re filling up fast.

              "Sooner or later, we’re going to have to ask local people to give us their land to use," Tsuneo Saito, a local boar hunter, told The Sunday Times. "The city doesn’t own land which isn’t occupied by houses."
         
             The most logical solution once these mass graves are filled to the brim is incinerating the rest of the radioactive carcasses, but you can’t just burn contaminated flesh - you need a special facility that’s capable of filtering out the radioactive materials so they’re not redistributed across the land via smoke particles.
 
                Andrews reports that a facility like this exists in the nearby city of Soma, but "it can only handle three boars a day (or 21 a week, which is only 1,092 each year; not quite 13,000)," he says.
So far, this is as close to a solution as the local farmers, hunters, and authorities have been able to get.
While nuclear meltdowns are tragic events for us humans, leading to a loss of life, homes, and livelihoods for so many people, many species of wildlife have shown incredible resilience in places humans fear to tread.

                As we reported back in October, populations of elks, deer, wolves, bears, lynx, and boars are thriving in the Chernobyl exclusion zone decades after the devastating meltdown, simply due to a lack of human interference. Sarah Kaplan reported for The Washington Post that some of these populations have more than doubled in recent years.
             
                   "That wildlife started increasing when humans abandoned the area in 1986 is not earth-shattering news," radio-ecology expert Tom Hinton from Fukushima University told her. "What’s surprising here was the life was able to increase even in an area that is among the most radioactively contaminated in the world."

                         Meanwhile, radioactive boars aren't the only thing local authorities in Fukushima are having to deal with. There's a whole lot of contaminated water still leaking out of the power plant, and no one's quite sure how to get rid of the radioactive tritium they're extracting from it.
One thing's for sure - humanity has never seen a disaster quite like this, and we've still got many years to go before this nightmare is over for the people trying to live in the area. All we can do is hope that science can come through with some answers.

Monday, April 11, 2016

A sugar can melt away cholesterol

A sugar that freshens air in rooms may also clean cholesterol out of hardened arteries.
The sugar, cyclodextrin, removed cholesterol that had built up in the arteries of mice fed a high-fat diet, researchers report April 6 in Science Translational Medicine. The sugar enhances a natural cholesterol-removal process and persuades immune cells to soothe inflammation instead of provoking it, say immunologist Eicke Latz and colleagues.
Cyclodextrin, more formally known as 2-hydroxypropyl-beta-cyclodextrin, is the active ingredient in the air freshener Febreze. It is also used in a wide variety of drugs; it helps make hormones, antifungal chemicals, steroids and other compounds soluble. If the new results hold up in human studies, the sugar may also one day be used to liquefy cholesterol that clogs arteries.
Other researchers say the approach is promising, but must be tested in clinical trials. The sweet molecule is generally considered safe, but injecting it may raise the risk of liver damage or hearing loss, says Elena Aikawa, a vascular biologist at Brigham and Women’s Hospital in Boston.
Mice taking cyclodextrin in the study did not exhibit side effects from the treatment, but previous work has indicated that the sugar may damage hearing in mice and cats. The molecule shunts cholesterol through the liver, so large cholesterol influxes might cause fat to build up in the liver, impairing its function. “Overall, cyclodextrin seems worth exploring as a therapeutic, although caution should be taken,” Aikawa says.
Cyclodextrin works by flipping a master switch, a gene called LXR, Latz and colleagues found. LXR’s protein turns on other genes involved in processing cholesterol and ushering it out of the body. The sugar also activated the LXR genes in human arteries examined in the lab and turned on inflammation-calming processes, Latz’s team discovered.
Latz, of the University Hospital Bonn in Germany, credits Nevada businesswoman Chris Hempel with the idea to use cyclodextrin to treat atherosclerosis. In people with the condition, cholesterol, calcium, immune cells and other substances form plaques inside arteries, hardening them. Plaques block blood flow and can break away and cause heart attacks and strokes (SN: 2/20/16, p. 32).
Hempel has twin daughters with a rare genetic disease known as Niemann-Pick Type C, in which cholesterol crystals clog organs, especially the brain. In 2009, the girls got special permission from the Food and Drug Administration for their doctor to give them infusions of cyclodextrin to dissolve the cholesterol crystals.
Hempel later read a paper by Latz and colleagues in which the researchers described how cholesterol crystals irritate macrophages and provoke them to cause inflammation and heart disease. Macrophages normally patrol the body and help kill invading bacteria, viruses and other pathogens. The immune cells also gobble up cholesterol and deliver it to the liver where it can be made into bile and escorted out of the body in feces.
Hempel e-mailed Latz and suggested that cyclodextrin might melt the cholesterol crystals in arteries. Latz and his colleagues tested the idea by feeding mice genetically prone to atherosclerosis a high-fat diet and giving the animals regular injections of cyclodextrin under the skin. The sugar kept cholesterol plaques from building up in the rodents’ arteries. The scientists also found that cyclodextrin reduced already established plaques in mice by about 45 percent, even though the animals were still eating a high-fat diet.
Cyclodextrin could be used in combination with other drugs, such as statins, says Eran Elinav, an immunologist at the Weizmann Institute of Science in Rehovot, Israel. Statins and other drugs inhibit cholesterol production. “Potentially, combining cholesterol lowering with dissolution of preformed cholesterol in plaques could be additive,” Elinav says, “but this option needs to be explored in clinical trials.”
Although cyclodextrin is already approved by the FDA for use in people, it may be years before it’s known whether injecting the sugar will soften people’s hardened arteries. The sugar is not patentable, so no pharmaceutical companies have come forward to sponsor expensive clinical trials needed to get approval for this specific use, Latz says. 


Sunday, April 10, 2016


New type of Dinosaur egg found in china  


Researchers just found a new type of dinosaur egg from the Lower Cretaceous period in northwestern China. The fossil was shown to have been around 100 million and 145 million years old. This is quite a find considering that eggs from the Upper Cretaceous period, which is younger and higher up the surface of the earth, are rare to find -- and the Lower Cretaceous even rarer still.

The eggs are so rare that according to UPI, it required scientists to establish a new "oogenus,""oospecies" and "oofamily" to be able to classify it.
The researchers were also able to list features that set it apart from other dinosaur egg species, specifically noting on how it evolved. Researchers described the new discovery as "branched eggshell units lacking a compact layer near the outer surface; interlocking or isolated multi-angular eggshell units, as viewed in tangential sections; and irregular pore canals."
The new eggs are now known as Polyclonoolithus yangjiagouensis, and are placed in a new family called Polyclonoolithidae -- of course, there is no telling how long they will stay in that classification, or if they can figure out soon if they are eggs from previously discovered dinosaurs. However, the eggs could possibly be related with other oofamilies like Dendroolithidae, Dictyoolithidae and Similifaveoloolithidae. Still, it is likely that there are still unknown dinosaur species preserved in the Lower Cretaceous deposits in China.
Phys.org noted that there have been several dinosaur skeletons found from the Early Cretaceous period in the Gansu Province, but the eggs have never been found.
Dr Zhang Shukang of the Institute of Vertebrate Paleontology and Paleoanthrology, Chinese Academy of Sciences said in a press release,  "The new discovery expands the geological and geographical distribution of the fossil record of dinosaur eggs in China and may reveal the origin of eggshell microstructures of spheroolithid eggs."
With these discoveries, researchers remain hopeful that excavation of more fossilized eggs may be possible in the future

Wednesday, April 6, 2016

The planet with THREE Suns: KELT-4Ab

Tatooine’s double sunset just got outshone. Astronomers studying a distant gas giant have found that the planet’s star system contains not one, not two, but three stars.

The planet KELT-4Ab, described in the Astronomical Journal, could help shed light on the complex dynamics of these multi-star systems – and particularly on the mysteries of planetary migration.

The KELT-4 system lies about 685 light-years away in the constellation Leo and, before the planet was found, had been thought to host only two stars. But now, thanks to new observations by the Kilodegree Extremely Little Telescope and several other telescopes, astronomers have found that the distant star is actually a binary -- made of not one but two stars.

This triple system is a binary within a binary, said lead author Jason Eastman, an astronomer at the Harvard-Smithsonian Center for Astrophysics. And it’s only the third known transiting planet in what’s known as a “hierarchical triple stellar system.” (The first were WASP-12b and HAT-P-8b; KELT-4Ab is the brightest of the three, and thus ripe for follow-up.)

“This is a particularly bright and nearby example of such a system and it’s one of few that are known,” Eastman said. “So that makes it particularly interesting.”


Kelt-4A is roughly 1.2 solar masses, and the two others have roughly half that, about 0.65 solar masses apiece, Eastman said. At 328 astronomical units (or 328 Earth-sun distances) away from Kelt-4A, the binary pair takes about 4,000 years to circle the larger star but only 30 years or so to circle each other.

Scientists Confirm the Existence of "Quantum Spin Liquid"

Researchers have just discovered evidence of a mysterious new state of matter in a real material. The state is known as 'quantum spin liquid' and it causes electrons - one of the fundamental, indivisible building blocks of matter - to break down into smaller quasiparticles.

Scientists had first predicted the existence of this state of matter in certain magnetic materials 40 years ago, but despite multiple hints of its existence, they've never been able to detect evidence of it in nature. So it's pretty exciting that they've now caught a glimpse of quantum spin liquid, and the bizarrefermions that accompany it, in a two-dimensional, graphene-like material.


"This is a new quantum state of matter, which has been predicted but hasn't been seen before," said one of the researchers, Johannes Knolle, from the University of Cambridge in the UK.

They were able to spot evidence of quantum spin liquid in the material by observing one of its most intriguing properties - electron fractionalisation - and the resulting Majorana fermions, which occur when electrons in a quantum spin state split apart. These Majorana fermions are exciting because they could be used as building blocks of quantum computers.

To be clear, the electrons aren't actually splitting down into smaller physical particles - which of course would be an even bigger deal (that would mean brand new particles!). What's happening instead is the new state of matter is breaking electrons down into quasiparticles. These aren't actually real particles, but are concepts used by physicists to explain and calculate the strange behaviour of particles.

And the quantum spin liquid state is definitely making electrons act weirdly - in a typical magnetic material, electrons behave like tiny bar magnets. So when the material is cooled to a low enough temperature, these magnet-like electrons order themselves over long ranges, so that all the north magnetic poles point in the same direction.

But in a material containing a quantum spin liquid state, even if a magnetic material is cooled to absolute zero, the electrons don't align, but instead form an entangled soup caused by quantum fluctuations.

"Until recently, we didn't even know what the experimental fingerprints of a quantum spin liquid would look like," said one of the researchers, Dmitry Kovrizhin. "One thing we've done in previous work is to ask, if I were performing experiments on a possible quantum spin liquid, what would I observe?"


To figure out what was going on, the researchers worked alongside a team from Oak Ridge National Laboratory in Tennessee and used neutron scattering techniques to look for evidence of electron fractionalisation in alpha-ruthenium chloride - a material that's structurally similar to graphene.

This also allowed them to measure the signatures of Majorana fermions for the first time by illuminating the material with neutrons, and then observing the pattern of ripples that the neutrons produced when scattered from the sample.

These patterns were exactly what they'd expect to see based on the main theoretical model of quantum spin liquid, confirming for the first time that they'd seen evidence of it happening in a material.

"This is a new addition to a short list of known quantum states of matter," said Knolle.

"It's an important step for our understanding of quantum matter," added Kovrizhin. "It's fun to have another new quantum state that we've never seen before - it presents us with new possibilities to try new things."

Some of those new things involve quantum computers - which would be exponentially faster than regular computers - so even though all of this sounds pretty theoretical, they could actually have some really exciting potential applications