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Tuesday, 25 July 2017

INFOGRAPHIC: STARSHIPS OF THE FUTURE


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Despite practically every sci-fi movie you've seen, getting to the stars ain't as easy as it looks. It'll require unforeseen breakthroughs and radical innovations that are decades if not centuries away - still, we clever little humans have a few plans on the drawing board. This infographic by Futurism presents some of the most exciting.

https://futurism.com/wp-content/uploads/2016/10/Starships-of-the-Future.jpg

Infographic Sources:
1.
Discover Magazine August 2003
2. Interstellar Space Travel: 7 Futuristic Spacecraft To Explore the Cosmos
3. Are Black Hole Starships Possible?
4. Project Daedalus - Interstellar Mission
5. Alcubierre drive
6. Project Icarus
7. Three Doc E Worksheets
8. Project World Ship
9. How to power a starship with an artificial black hole
10. Starship Pioneers
11. John Cramer. “Exotic Technologies for Interstellar Travel.” Starship Century: Toward the Grandest Horizon. Eds. James Benford & Gregory Benford. Microwave Sciences, 2013: 279-299.

Top image (bottom): The Alcubierre drive. Credit: AllenMcC./Wikimedia Commons.

[Post Source: Futurism.]

Monday, 24 July 2017

10 HYPOTHETICAL ASTRONOMICAL OBJECTS THAT COULD ACTUALLY EXIST


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10 Hypothetical Astronomical Objects That Could Actually Exist
By Paulina Destarac,
Listverse, 24 July 2017.

Space has undoubtedly been a fascinating part of reality for humanity. Ever since we were able to understand our surroundings, we’ve looked up at the stars in search for answers, inspiration, and constancy. Space has been the muse for hundreds of movies and thousands of books. It has inspired calendars and horoscopes that detail how the arrangement of astronomical objects can predict personality traits and major life events.

Space has also inspired numerous visions of the future. We’ve conjured up scenarios of interplanetary travel, alien communication, and even time travel via wormholes. The items on this list look like they have been taken from an old science fiction book. However, numerous scientists believe these objects could exist somewhere in the vastness of space. Here are the top ten hypothetical astronomical objects that could actually exist.

10. Zombie Star

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Photo credit: NASA, ESA

As the name suggests, this type of star is one that, in a way, comes back from the dead. We’ve all heard of a supernova being referred to as the “death” of a star. In most cases, supernovae do mark the end of stars’ lives, since, during those grand explosions, the star is completely obliterated. However, scientists at NASA now believe that a faint supernova could leave behind a surviving portion of the dying dwarf star.

Astronomers first thought about the possibility of zombie stars when they observed a faint blue star feeding energy to its larger companion star. This process ignited a relatively small supernova, a Type Iax, which is low in brightness and does not spew out as much stellar mass as its cousin, the Type Ia supernova. So far, this is the only known way a white dwarf can explode. Typically, stars that explode at the end of their lifetimes are large, massive, and have very short life spans. White dwarfs, on the other hand, are cooler and tend to live longer, since they do not typically explode. Instead, they tend to expel their mass and create a planetary nebula. NASA scientists believe they have identified 30 of these Type Iax supernovae that leave behind a surviving white dwarf, but additional evidence is needed to safely say that they exist.

9. White Hole

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White holes were theorized by scientists who were working with black holes. While they were working through the complex mathematics associated with black holes, they found that by assuming the singularity at the center of a black hole had no mass, or by assuming that there was no mass within the event horizon, a white hole could be created.

The math explains that if white holes are real, they would behave exactly unlike black holes. That is, instead of sucking up all the matter around them, they would eject matter into the universe. However, the math also states that white holes could only exist if there was absolutely no matter inside the event horizon, not even a tiny cookie crumb. In the instance one atom of matter enters the white hole’s event horizon, it would collapse and disappear, so even if these white holes existed in the beginning of our universe, their life spans would have been incredibly short, since our universe is filled with matter.

8. Dyson Sphere

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The concept of a Dyson sphere was first introduced by Freeman Dyson, a physicist and astronomer who explored the idea through a thought experiment. He imagined a solar system-sized solar power collector. He believed a civilization could enclose its star in a cloud of satellite-type objects (or a “shell” or “ring of matter” in Dyson’s words) in order to beam 100 percent of the star’s radiation to a planet. Dyson created this thought experiment as a way to identify possible alien life in the universe. If we were to find a Dyson sphere, it could indicate the presence of a highly advanced alien civilization.

Here’s a cool fact: If we had the technology to create a Dyson sphere around the Sun, we would generate 384 yottawatts of energy, aka the total power output of the Sun. (Yotta- is the largest decimal unit prefix. It is equal to ten to the 24th power, or one septillion, or one million million million million.)

7. Black Dwarf

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Black dwarf - the name itself does not invoke sci-fi vibes as “zombie star” does. However, the concept behind a black dwarf is equally as interesting as all the other hypothetical objects on this list. So far, astronomers have found white dwarfs, brown dwarfs, and red dwarfs. However, black dwarfs have never been seen and are purely theoretical. Astronomers believe they could be formed from white dwarfs that have cooled for a sufficiently long time, to the point where their temperature matches the temperature of the Cosmic Microwave Background. The CMB is the radiation left over from the Big Bang that fills up the entire universe. It currently has an average temperature of 2.7 Kelvin.

These black dwarfs are thought to be invisible, since their temperature is so low and they have no internal source of energy. Theoretically, if a 5-Kelvin white dwarf was to turn into a black dwarf, it would take 1015 years. Therefore, the universe is still too young to have created any black dwarfs!

6. Quark Star

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Photo credit: Science

Quark stars, also called strange stars, are thought to be composed of a soup of quarks - the fundamental constituents of matter. Astronomers believe that these stars can be created after a medium-sized star (about 1.44 times the size of our Sun) has run out of fuel and has entered the collapsing stage of its lifetime. As it collapses, it squeezes protons and electrons together, eventually forming neutrons. However, scientists think that if the star is heavy enough and continues collapsing after this stage, the neutrons that were created could break down into their component quarks under the immense pressure, creating an incredibly dense type of matter.

A paper published in 2012 delves into the hypothetical nature of these strange quark stars. The authors of the paper explain that these stars could be enveloped in a thin nuclear “crust,” consisting of heavy ions immersed in an electron gas. However, they could also exist without the crust. In that case, the quark stars would possess ultra-high electric fields that could reach up to 1019 Volts per centimeter!

5. Ocean Planet

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Photo credit: Anynobody

As the name suggests, ocean planets, or water worlds, are thought to be composed entirely of vast, uninterrupted oceans. The idea of water worlds became popular when NASA announced the existence of two planets outside of our solar system: Kepler-62e and Kepler-62f. These planets are thought to be water worlds that could harbor a wealth of aquatic life.

A paper published in June 2004 explains how these types of planets could be formed. It is believed that they form relatively far away from their parent star and slowly migrate toward it (over a time period of about a million years). The planet would have to come five to ten times closer to the star, depending on how far away it initially formed. The paper delves into the internal structure of the planets as well as how deep their oceans could be and what their atmospheres could be composed of. Interesting read!

4. Chthonian Planets

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Photo credit: ESO/L. Calcada

The idea of Chthonian planets became popular thanks to an extrasolar planet nicknamed Osiris. NASA scientists were baffled when they detected carbon and oxygen for the first time in an atmosphere outside of our solar system. However, Osiris’s atmosphere was seen to be rapidly evaporating.

Scientists have designated a new class of worlds called Chthonian planets, which are created when gas giants, like Jupiter, enter a critical distance from their parent star. When they get too close, their outer layers begin to rapidly evaporate. Chthonian planets are thus the remnants of these gas giants, which have been stripped of their outer layers, leaving behind a dense central core.

3. Preon Star

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A preon star is something that could follow a quark star. As a star is compressed to the point where it becomes a quark star and is still massive enough to continue its collapse, scientists believe that the quarks themselves could break down into these theoretical preons.

So far, scientists have not found a way to break down quarks, so they remain the main constituents of matter. However, if quarks are made of other individual particles - these so-called preons - stars could technically achieve this even denser state, one of matter created entirely of a soup of hyper-dense preons.

2. Ghost Galaxy

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Ghost galaxies, also called dark galaxies, are galaxies that have very few stars. They’re so inefficient at making stars that they’re thought to be mostly composed of gas and dust, making them basically invisible. As of now, they remain theoretical for this very fact, but astronomers believe that dark galaxies are likely to exist. An international team of scientists even thinks they have found the first dark galaxy. However, more data analysis needs to be done before it is confirmed.

Astronomers believe they have also found a different type of ghost galaxy, one that is 99 percent dark matter. They named it Dragonfly 44, and it seems to be the Milky Way’s dark doppelganger in mass, but it contains very few stars and is different in its structure. If this galaxy is ever observed or analyzed in enough detail, it could change how astronomers perceive galaxy formation and dark matter.

1. Cosmic Strings

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Cosmic strings are an insane idea, but the craziest part about them is that they could actually exist. Cosmic strings are slight defects in the fabric of space and time that were created at the beginning of time, left over from the formation of the universe. If one were to interact with one of these defects, one could create a “closed time-like curve,” which would allow for backward time travel. Scientists have speculated how they can make time machines out of these cosmic strings. They believe that by putting two of them close enough together, or one string and one black hole, they could create an array of these closed time-like curves.

To better visualize this, picture the cosmic strings as loops of space-time. Imagine picking up one loop and throwing it across space directly toward another loop. Then, imagine jumping on a space ship and flying around them in a perfect figure eight. This would allow you to emerge at any random point in space and time!

Although these objects are purely theoretical, astronomers believe that, if they exist, they would be very small “lines” in the fabric of space, and their effects would be incredibly strange. It is also believed that their existence could explain bizarre effects observed in faraway galaxies.

Top image: Dyson Sphere by SPAR/DeviantArt.

[Source: Listverse. Edited. Top image added.]

INFOGRAPHIC: BIO-ROBOTS - ANIMAL INSPIRED MACHINES


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Biomimetic robots, or bio-robots, are those that mimic the movements of natural creatures. Of particular interest to scientists is how animal bone and limb structures translate to unique locomotion - crawling, slithering, swimming, scaling walls and even flapping wings. Such robots have the potential to assist humans in a variety of ways. They could creep into tight spaces to inspect damaged facilities, squirm into tiny crevices to search for trapped survivors, or provide aerial surveillance to government organizations tracking  poachers. The following infographic by Futurism illustrates some of the ones that already exist.

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[Source: Futurism.]

Sunday, 23 July 2017

10 OF THE WORLD'S MOST COLORFUL CITIES


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10 of the world's most colorful cities
By Josh Lew,
Mother Nature Network, 20 July 2017.

Travelers may say they visit a place because of its attractions, but sometimes the reason is based on something much simpler and much less tangible. Sometimes, visitors just like the looks of a place.

Towns with bright buildings and structures with creative paint schemes are popular throughout the world. Tourists flock to photograph brightly painted streetscapes in Chefchaouen, Morocco (pictured top), India, the Mediterranean, the Caribbean and even the Arctic.

If that's you, if you're drawn to places with colorful buildings, these 10 cities are calling.

1. Jaipur

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Photo: Chirag Pai/Wikimedia Commons

The capital of the Indian state of Rajasthan, Jaipur is known as the Pink City. With a few exceptions, all the buildings within the historic city center are pink. This unusual color choice dates to the 19th century when a Rajasthani king ordered all buildings to be painted pink ahead of a visit by England's Prince Albert, the Prince of Wales, in 1876. The color choice was meant to evoke a sense of hospitality and welcoming.

The unique visual appeal of Jaipur is enhanced by its architecture. The City Palace, Amber Fort and Hawa Mahal (pictured above) are a few popular sites, while a host of temples, gardens and squares allow people the chance to fill out their sightseeing itinerary.

2. Willemstad

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Photo: AJEL/Pixabay

Willemstad's colorful buildings date to the early 19th century, when it was the capital of the Dutch colony known as the Netherlands Antilles. White was the dominant color of the Caribbean island's structures at that time, but the colonial governor, named Albert Kikkert, suffered from debilitating migraines, and the sunlight reflecting off the white facades reportedly made his condition worse. He ordered the buildings' owners to paint their walls using other colors. Though Kikkert has long since passed away, the colorful tradition has survived.

The bright paint jobs of this city have earned it recognition from organizations like UNESCO, which has named the Curaçao capital a World Heritage Site. The island is popular for its casinos, beaches and resorts, but many visitors also stroll through the historic areas like Punda and Otrobanda. In all, there are more than 800 designated historic and archaeological sites on the island.

3. Jodhpur

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Photo: Rhiannon/Pixabay

Like the Pink City, Jodhpur is another city in Rajasthan, India, that is noted for the uniform color of its buildings. Located on the edge of the Thar Desert, Jodhpur has two nicknames. It is known as the Blue City because of the color of the buildings in the historic center, and it is also called the Sun City because of its cloudless climate. Once an important trading center, Jodhpur has continued to grow, and the metropolis now stretches well beyond the old town. Tourists flock here, not just for the blue houses, but also for the historic temples, palaces and gardens. The 15th century Mehrangarh Fort is one of the most popular of these attractions.

Blue was originally the color of the Brahmins, the high-caste of priests and teachers. And though the caste system is officially banned by the country's constitution, the blue-hued tradition remains, with people from other levels of Indian society also adopting the color for their homes.

4. Bo-Kaap, Cape Town

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Photo: SkyPixels/Wikimedia Commons

Bo-Kaap (also written Bo Kaap) is a multicultural neighborhood in Cape Town, South Africa, that is known for its brightly painted buildings and cobblestone streets. Formerly known as the Malay Quarter, it has been a predominantly Muslim district for more than a century, and it has one of South Africa's oldest mosques. Most inhabitants' ancestors are from the Indian subcontinent and insular Southeast Asia. Afrikaans has long been the language of this community, though English continues to gain ground. The historic two-story homes and bright paint schemes have made this neighborhood a popular stop for tourist photo ops.

No one has a definitive answer as to why the houses in Bo-Kaap are so brightly painted. Some claim that residents merely choose the bright colors because they were the cheapest hues available. Others claim that the colors were painted to celebrate the multicultural makeup of the neighborhood or to demonstrate independence after the end of apartheid. One theory is that the neighbors on a specific street coordinated their painting so that none of the houses on the block clashed with any others.

5. Cinque Terre

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Photo: Harald_Landsrath/Pixabay

Cinque Terre is a region in northwest Italy on the Ligurian Sea. Translated as "five lands," Cinque Terre consists of five villages perched on the coastline overlooking the Mediterranean. The five communities - Monterosso, Vernazza, Corniglia, Manarola (pictured) and Riomaggiore - were extremely isolated until they were connected with the rest of the country by rail in the 19th century. Because some of the towns are still inaccessible by car, trains and ferries remain the preferred means of transportation today.

Cinque Terre experienced a tourism boom starting in the 1970s. The tradition of bright-colored buildings is not an old one; the trend started with the increase in the number of tourist arrivals. Despite the origins of this tradition, visitors often praise the lack of tourist development and the absence of brand names and corporate hotels in Cinque Terre.

6. Guanajuato

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Photo: Bud Ellison/Flickr

Located in the mountains of Central Mexico, Guanajuato was once a center of the silver mining industry. Visitors can trace the city's past by visiting the many 16th century plazas and churches scattered throughout the hillsides.

Brightly painted buildings are found all around Guanajuato. Unlike many Mexican cities, this place is free from traffic jams. The narrow streets are simply too difficult for cars to navigate. Despite the pleasant setting, there are not many tourists in Guanajuato. Most visitors seem to prefer the similarly historic (but less colorful) San Miguel de Allende, about an hour away.

7. Nuuk

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Photo: patano/Wikimedia Commons

Greenland's cultural and political center, Nuuk has a population of just over 17,000, making it one of the world's smallest capitals. Nuuk is surrounded by mountains, waterways and fjords, and it serves as a gateway to Greenland's nature tourism and Northern Lights excursions. Most tourists start and end their Greenland journey here.

For a long time, Nuuk's architecture was focused on function, not attractiveness. However, as the territory gained more autonomy from Denmark, it re-embraced more traditional housing. Brightly colored paint jobs became the norm in some parts of the city, and a blend of native and colonial architecture, with both modern and traditional elements, can be seen in the public buildings around town.

8. St. John's

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Photo: Pexels/Pixabay

Originally founded in 1497, St. John's is North America's oldest city. Now a hip Newfoundland enclave, it is known for its candy-hued houses, vibrant art and music scenes, creative restaurants and youthful energy. It is also a convenient base for exploring the scenic Avalon Peninsula by car, boat or on foot.

The hilly terrain begs comparisons with San Francisco, and the pastel buildings, both residential and commercial, add to the lighthearted, creative vibe of St. John's. Zoning rules, which limit height and other details, have kept the British colonial-era feel in place in the center of the city (though critics say that this has slowed development). The heritage buildings and bright colors make St. John's feel different than almost any other place in North America.

9. Chefchaouen

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Photo: Singa Hitam/Flickr

The deep blue paint, narrow lanes and historic architecture make Chefchaouen, Morocco, one of the world's most atmospheric towns. Founded in the 1470s, early residents, Jewish and Muslim refugees fleeing the Spanish Inquisition, started painting their homes blue, a tradition that has lasted until this day.

Why blue? The prevailing theory is that Jewish settlers choose the color because it mimicked the sky and served to constantly remind them of God. Since the 1960s, Chefchaouen has experienced a tourism boom. First popular with intrepid backpackers and marijuana-seeking hippies, it now draws a wide range of visitors hoping to experience the uniquely colorful ambiance.

10. Tobermory

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Photo: hendersona980/Pixabay

Located on the Isle of Mull in Scotland, Tobermory has a population of about 1,000. It began as a fishing village, but is now also a tourist destination. It is known for the colorful buildings - mostly shops and restaurants, but also private residences - that line its waterfront and Main Street.

Tobermory was the filming location for a popular BBC children's series called "Balamory." Families of young fans are a large percentage of the town's tourists. The well-respected Tobermory Distillery is also located here. The town seems committed to its colorful image. One of the most notable buildings in the center of town, the Mishnish Hotel, was painted black (a typical color for pubs) about a decade ago, but soon after changed back to a bright yellow hue.

Top image: The blue city of Chefchaouen, Morocco. Credit: eyw2008/Pixabay.

[Source: Mother Nature Network. Some images added.]

Saturday, 22 July 2017

INFOGRAPHIC: WHICH BROWSER IS MOST SECURE?


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Internet security is becoming increasingly important, especially as more and more of our data is being shared and stored online. Whenever you go on a website, you’re exposing yourself to risks, including computer viruses and personal data theft. But is there such thing as the “most secure” online browser - and how can you take extra steps to make sure you’re surfing safely? This infographic by Who Is Hosting This provides the answer.

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[Post Source: Who Is Hosting This.]

Thursday, 20 July 2017

INFOGRAPHIC: 9 WAYS TO REDUCE FOOD WASTE IN THE SUPPLY CHAIN


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Around a third of food produced for human consumption is wasted. That’s 1.3 billion tons of food each year! There is a lot of information out there about reducing food waste in homes and once it has reached shops, but nowhere near as much about waste in the supply chain. Not only will cutting down on food waste in the supply chain save businesses money, but it is a vital component in solving the world’s hunger problem. This infographic by Go Supply Chain introduces nine ways to reduce waste, focusing specifically on the supply chain.

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[Post Source: Go Supply Chain.]

Wednesday, 19 July 2017

5 COFFEE BREAK TRADITIONS FROM AROUND THE GLOBE


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5 coffee break traditions from around the globe
By Robin Shreeves,
Mother Nature Network, 17 July 2017.

Coffee drinkers are excited about recent studies that indicate heavy coffee consumption may lead to a longer life. Three cups a day may lower the risk of death from conditions like heart disease, stroke, diabetes, cancer and kidney disease. Anyone - including me - who finds solace in coffee throughout the day is probably thinking, "If this is true, I'm going to live forever."

We don't, however, become coffee drinkers because we think it's going to help us live longer. We become coffee drinkers because the hot beverage helps us wake up or stay awake. We become coffee drinkers because we enjoy the taste - often mixed with milk and sugar at first. We become coffee drinkers because it's simply something steeped into our culture, and many cultures have their own traditions for taking time out during the day for an intentional, satisfying cup.

Here in the United States, that timeout is known as the coffee break, and it began around the same time as unions gained the rights for workers to have a break during their eight-hour workday in factories, according to City Lab. Coffee was the drink of choice for workers who had a short time away from their tasks. Today, we take frequent trips to the break room for a cup of Joe that is consumed back at the desk or elsewhere on the job.

How do other cultures handle their coffee breaks, and what do they call them?

1. Buna Tetu

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In Ethiopia, Buna Tetu, which means "drink coffee," is the name for the coffee ceremony that can take up to three hours to prepare - and it happens three times a day. Buna Tetu is a time to socialize, and it's an important part of the culture. The ceremony is performed by a woman and starts off with a ritual that wards off evil spirits. It consists of everything from roasting the raw coffee beans to grinding them to making the coffee, according to the Spruce. It's an involved process with several specific steps.

When the coffee is served, if there is a small child, she will serve the oldest person at the ceremony, and then the hostess will serve the rest of the family or guests. Guests can have up to three cups of coffee, each getting progressively weaker. Three cups of coffee three times a day? According to those recent studies, Ethiopians' coffee habits may lead to very long lives.

2. Fika

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In Sweden, Fika is a daily coffee break that's a regular part of the workday. Office workers have a chance to chat and enjoy something sweet in the form of a pastry. According to Mahabis, workers earn up to five minutes of coffee break for every hour they work. Coffee houses are designed around the Fika concept, set up so people can take their time, relax, socialize and savor their coffee.

3. Merienda

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Is it still a coffee break if the beverage of choice isn't always coffee? Merienda is the afternoon tea or coffee break in some parts of Latin America. It's a small meal between lunch and dinner, according to Inside Buenos Aires. A traditional Argentine merienda may consist of coffee with milk and croissants, tea with milk and toast, or submarino - hot milk with a piece of chocolate dunked in it. In the summer, hot beverages may be pushed aside for a banana smoothie. Kids have merienda, too. It's an afternoon snack for them to give them some energy mid-afternoon.

4. Gabelfrühstück

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In countries like Austria and Germany, Gabelfrühstück, literally "fork breakfast," is a second breakfast. The first breakfast eaten before work is consumed quickly - maybe coffee and a piece of fruit or a pastry - but between 10 and 11 a.m., the tradition is to take a Gabelfrühstück. People have another cup of coffee and sit down with something more filling that requires utensils to eat. Even schools have been known to have this mid-morning break, according to the Kitchn (perhaps without the coffee, though).

5. Smoko

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Photo: pavlelederer2/Pixabay

When manual laborers won the right to afternoon and morning breaks, those breaks became known as smokos - a time for coffee or tea, frequently accompanied by a cigarette. The term isn't used only for work breaks anymore; smoko is slang for any coffee break or between-snack. For the longest time, smokos were required by law for workers, but in 2014 Parliament took the right away, according to Stuff.

Top image credit: Alexas_Fotos/Pixabay.

[Source: Mother Nature Network. Edited. Some images added.]

Tuesday, 18 July 2017

11 BODY PARTS GROWN IN THE LAB


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11 Body Parts Grown in the Lab
By Mindy Weisberger,
Live Science, 3 July 2017.

Regrowing a missing limb is no big deal - to a starfish or salamander, creatures that are well-known for using regenerative "superpowers" to replace missing arms and tails. But they aren't the only animals that can rebuild body parts that are destroyed or damaged. Deer can re-sprout as much as 66 lbs. (30 kilograms) of antlers in only three months. Zebrafish can regrow their hearts, while flatworms have demonstrated that they can regenerate their own heads.

For humans, though, what's lost is lost - or is it?

Individual cells in your body are constantly being replaced as they wear out, a process that slows with aging but continues throughout the human lifetime. You can even observe this frequent and visible regeneration in one of your organs: your skin. In fact, humans shed their entire outer layer of skin every two to four weeks, losing about 18 ounces (510 grams) of skin cells per year, according to the American Chemical Society.

However, regenerating complete organs and body parts, a common practice among "Doctor Who's" Time Lords, is beyond the scope of human biology. But in recent years, scientists have successfully cultivated a range of human body structures, similar structures that have been successfully tested in animals, and small-scale human organs known as "organoids," which are used to study human organ function and structure at a level of detail that was previously impossible. Here are some recent examples:

1. Fallopian tubes

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Using stem cells, scientists from the Max Planck Institute for Infection Biology in Berlin grew the innermost cellular layer of human fallopian tubes, the structures that connect the ovaries and uterus. In a statement released on Jan. 11, the researchers describe the resulting organoids as sharing the features and shapes that are particular to full-size fallopian tubes.

2. Mini-brain

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A lab-grown brain the size of a pencil eraser was cultivated from skin cells by The Ohio State University (OSU) scientists, and is structurally and genetically similar to the brain of a 5-week-old human fetus. Described as "a brain changer" by OSU representatives in an Aug. 18 statement, the organoid has functioning neurons with signal-carrying extensions like axons and dendrites. In the photo of the mini-brain, labels identify structures that are typically found in a fetal brain.

3. Mini-heart

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Researchers prompted stem cells to develop into heart muscle and connective tissue, and then organize into tiny chambers and "beat." In a video of the achievement, the heart muscle cells (indicated by red at the center) are beating while connective tissue (green ring) secures the mini-heart to the dish where it grew. Kevin Healy, a University of California, Berkeley, professor of bioengineering and co-senior author of the study, said in a statement. "This technology could help us quickly screen for drugs likely to generate cardiac birth defects, and guide decisions about which drugs are dangerous during pregnancy." The research was published March 2015 in the journal Nature Communications.

4. Mini-kidney

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A team of Australian scientists grew a mini-kidney, differentiating stem cells to form an organ with the three distinct types of kidney cells for the first time. The researchers grew the organoid in a process that followed normal kidney development. In the image, the three colors represent the types of kidney cells that form "nephrons," the different structures within the kidney.

5. Mini-lung

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Researchers from several institutions collaborated to grow 3D lung organoids that developed bronchi, or airway structures, and lung sacs. "These mini-lungs can mimic the responses of real tissues and will be a good model to study how organs form [and] change with disease, and how they might respond to new drugs," Jason R. Spence, senior study author and an assistant professor of internal medicine and cell and developmental biology at the University of Michigan Medical School, said in a statement. The mini-lungs survived in the lab for more than 100 days.

6. Mini-stomach

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Mini-stomachs that took about one month to cultivate in a petri dish formed "oval-shaped, hollow structures" resembling one of the stomach's two sections, said Jim Wells, study co-author and a professor of developmental biology at Cincinnati Children's Hospital Medical Center. Wells told Live Science that the tiny stomachs, which measured about 0.1 inches (3 millimeters) in diameter, would be especially helpful to scientists studying the effects of a certain bacterium that causes gastric disease. This is because the bacteria behave differently in animal subjects, he said.

7. Vagina

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Credit: Dr. Yuanyuan Zhang, Wake Forest Institute for Regenerative Medicine, via Live Science

In April 2014, a study published in the journal The Lancet described the successful transplants of lab-grown vaginas, created by nurturing the patients' cells on a vagina-shaped scaffold. The transplants, conducted several years earlier in four girls and young women between the ages of 13 and 18, corrected a congenital defect in which the vagina and uterus are missing or underdeveloped. The teenagers were examined annually for eight years after the transplants, during which time the organs functioned normally, allowing pain-free intercourse.

8. Penis

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Scientists at the Wake Forest Institute for Regenerative Medicine used rabbit cells to grow penile erectile tissue, transplanting the lab-grown penises onto male rabbits, which then mated successfully. But the process is still in the experimental stages, and approval from the US Food and Drug Administration is required for the team to extend its work and incorporate human tissue and subjects. The U.S. Armed Forces Institute of Regenerative Medicine is providing money for the study, as the research could benefit soldiers who suffered groin injuries in combat.

9. Esophagus

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Credit: Macchiarini et al. via Live Science

At Kuban State Medical University in Krasnodar, Russia, an international team of scientists constructed a working esophagus by growing stem cells on a scaffold for three weeks; they then successfully implanted the organ in rats. The scientists tested the new esophagus for durability by inflating and deflating it 10,000 times, implanting the artificial structures in 10 rats and replacing up to 20 percent of the animals' original organs.

10. Ear

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Now hear this: Scientists have 3D printed human ears, cultivating them by coating molded ear-forms with living cells that grew around the frame. The researchers created the ear-shaped mold by modeling a child's ear using 3D software and then sending the model to a 3D printer. Once the scientists had the mold in hand, they injected it with a cocktail of living ear cells and collagen from cows, and "out popped an ear," Live Science reported. The fabricated ears were then implanted on rats for one to three months while scientists evaluated changes in size and shape as the organs grew.

11. Liver cells

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The liver, the largest organ inside the human body, is capable of great feats of repair and regeneration while in its proper place. Outside the body, the organ has provided a challenge; it has proven exceedingly difficult for scientists to grow liver cells, called hepatocytes, and keep them alive. For the first time, scientists from Germany and Israel successfully cultivated hepatocytes in the laboratory, publishing their research Oct. 26, 2015, in the journal Nature Biotechnology. Though not a full-fledged organ (or even an organoid), this development holds promising implications for clinical study, with Yaakov Nahmias, director of the Alexander Grass Center for Bioengineering at the Hebrew University of Jerusalem and the study's lead author, describing it in a statement as "the holy grail of liver research.”

Top image: A lab-made urethra. Credit: Wake Forest School of Medicine.

[Source: Live Science. Top image added.]