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Reforestation

What is reforestation?

Reforestation involves the replanting or regeneration of areas of forest which have previously been damaged or destroyed. Sometimes forests are able to regenerate naturally if sufficient trees remain nearby and seeds can be dispersed into the deforested areas via animals or wind. However, areas of forest which have been severely degraded are unlikely to be able to regenerate naturally and need to be replanted by hand using native tree species.

Why is reforestation needed?

Reforestation is needed because huge areas of forest are being damaged or destroyed around the world on a daily basis. Some estimates suggest that an area of forest equivalent in size to 36 football pitches is lost every minute. This deforestation has a number of causes, including fires, the clearing of land to make way for agriculture or human settlement, logging, mining and climate change.

Forests are very important for a number of reasons and deforestation is a serious problem which affects us all. As well as being home to a huge and diverse range of animal and plant species, forests provide livelihoods for a vast number of people around the world and are a source of paper, timber, food and the ingredients of many other products, such as medicines and cosmetics. Forests are also vital for the health of our planet, maintaining the water cycle, preventing soil erosion and absorbing and storing enormous amounts of carbon dioxide which helps to limit the effects of climate change.

In order to tackle deforestation there are a number of organisations around the world that aim to replant trees and help to regenerate and restore forest habitats.

Reforestation facts

  • Reforestation usually involves replanting areas of forest which have previously been damaged or destroyed, using native tree species.
  • Reforestation is of great importance, as estimates suggest that at the current rate of deforestation, there may be no rainforest left within 100 years.
  • Huge areas of forest have already been lost, for example, only around eight percent of the Atlantic forest in South America now remains.

read more from ARKive 

That’s like being mind-controlled by bacteria…Further details: L#1: http://is.gd/pDCgLYL#2: http://is.gd/VMziKUImage via: http://is.gd/h2XQJh
through Hashem AL-ghaili (go follow him on facebook, if you haven’t ready)

That’s like being mind-controlled by bacteria…

Further details: 

L#1: http://is.gd/pDCgLY
L#2: http://is.gd/VMziKU

Image via: http://is.gd/h2XQJh

through Hashem AL-ghaili (go follow him on facebook, if you haven’t ready)

Sectoral heterochromia Heterochromia iridis is a condition in which the iris in one eye has a different color than the iris of the other eye or shows different colours within the same eye. The iris is the tissue of the eye that surrounds the pupil and imparts a color, whether green, blue, brown, hazel, grey, or other, to the eye. Iris color is the result of the pigment that is present in the iris. Brown eyes have large amounts of melanin pigment deposits, and blue eyes have a lack of melanin. Although eye color is inherited, the inheritance pattern is complex, with interaction of more than one gene. These genes interact to provide the full constellation of colors. Other genes may determine the pattern and placement of pigment in the iris, thereby accounting for solid brown as opposed to rays of color. Normally, the two irises of an individual are of the same color. In heterochromia, the affected eye may be hyperpigmented (darker or hyperchromic) or hypopigmented (lighter or hypochromic). Eye color is determined primarily by the concentration and distribution of melanin within the iris tissues.Text by medicinenet.comImage found on postgrad-premed.tumblr.com/
through Daily Anatomy 

Sectoral heterochromia 

Heterochromia iridis is a condition in which the iris in one eye has a different color than the iris of the other eye or shows different colours within the same eye. The iris is the tissue of the eye that surrounds the pupil and imparts a color, whether green, blue, brown, hazel, grey, or other, to the eye. 

Iris color is the result of the pigment that is present in the iris. Brown eyes have large amounts of melanin pigment deposits, and blue eyes have a lack of melanin. Although eye color is inherited, the inheritance pattern is complex, with interaction of more than one gene. These genes interact to provide the full constellation of colors. 

Other genes may determine the pattern and placement of pigment in the iris, thereby accounting for solid brown as opposed to rays of color. Normally, the two irises of an individual are of the same color. In heterochromia, the affected eye may be hyperpigmented (darker or hyperchromic) or hypopigmented (lighter or hypochromic). Eye color is determined primarily by the concentration and distribution of melanin within the iris tissues.

Text by medicinenet.com
Image found on postgrad-premed.tumblr.com/

through Daily Anatomy 

Watch What Could Be This Summer’s Best Meteor Shower

Fact of the Day:The giant squid, or Architeuthis dux as it’s scientifically known, has a complex yet small donut-shaped brain. The squid’s oesophagus runs through the ‘donut-hole’ of the brain making it essential for food to be ground into small pieces by it’s notorious beak.Read more about this fascinating creature herewww.ocean.si.edu/giant-squid (Graphic via funnyjunk.com)
source 

Fact of the Day:
The giant squid, or Architeuthis dux as it’s scientifically known, has a complex yet small donut-shaped brain. The squid’s oesophagus runs through the ‘donut-hole’ of the brain making it essential for food to be ground into small pieces by it’s notorious beak.
Read more about this fascinating creature herewww.ocean.si.edu/giant-squid 
(Graphic via funnyjunk.com)

source 

(fun fact: I have the first and third photographs on my door :) )

Q&A: Scientist Studied His Poop for a Year to Learn About Gut Bugs

Gut microbes may be key to human health, but tracking them proves a tough task.

Karen Weintraub

for National Geographic

PUBLISHED JULY 24, 2014

Where would we be without our gut bugs? These bacteria help us do everything from digesting food to recovering from disease, but scientists are still learning exactly what gut bugs do, and even how to study them.

In the latest report from this inner frontier of science,Lawrence David, formerly a graduate student at the Massachusetts Institute of Technology, and his adviser, Eric Alm, tracked their own bodily functions—which largely meant studying their poop and pee—to see what might alter the colonies of bacteria that live in their guts. (Related: "Why Has This Really Common Virus Only Just Been Discovered?")

They used cutting-edge DNA analysis and also perhaps the oldest health metric ever used by humans, studying their own feces. The results of their 2009-2010 adventure are published Thursday in the journal Genome Biology.

National Geographic talked to David, now an assistant professor at Duke University in Durham, North Carolina, about the experience and what he learned.

For the most part, were gut bugs pretty stable across time?

The most abundant species you would see for days, weeks, months. We couldn’t find very many lifestyle variables that would cause a new species to show up or disappear.

You write in the study that the biggest change you saw was from an accidental food poisoning.

In about a week, about half the [bacterial] species that had been very abundant became much, much, much less abundant. Many of them dropped to at or below our detection limit.

You also saw some quick changes in gut bugs from eating fiber. Were you intentionally eating fiber to see what would happen?

The subjects were instructed not to alter their diets. The power of our study was that we weren’t telling people, “You have to eat fiber bars for this one week and then we’re going to analyze it.” We said, “Just live your life the way you normally would and we’ll see what we can learn.”

Wait a minute. You refer to the people in your study as “the subjects,” but weren’t they really you and your adviser, Eric Alm?

As scientists, we were trying to be as impartial as possible in how we analyze our data and interpret it. In many ways it was a pilot study. We were trying to figure out what kind of host actions could be tracked and what was feasible to look at in people over time. In a pilot study, we didn’t want people doing things that we ourselves wouldn’t really be comfortable doing.

Are there metrics that will be too difficult to ask future subjects?

Now I know that tracking things like urination [is too onerous]. Compliance would probably be abysmal.

read more from NatGeo

World’s Largest Freshwater Turtle Nearly Extinct
The last known pair of Yangtze giant softshell turtles mated again in June.
Kaitlin Solimine
for National Geographic
PUBLISHED JULY 1, 2013

The fate of a species is resting on the shells of two turtles at China's Suzhou Zoo.
n June, researchers collected eggs from the last mating pair of the critically endangered Yangtze giant softshell turtle (Rafetus swinhoei) in the hopes that at least one will be fertile.
The 220-pound (100-kilogram) freshwater giant, which spends most of its life burrowing in mud, was once common in its namesake Yangtze River, China’s Lake Taihu and Yunnan Province, and parts of Vietnam.
By the late 1990s, however, human encroachment and poaching for use of the shells in Chinese traditional medicine rapidly depleted the population. Now, a total of four animals are known—two wild males in Vietnam and the mating pair at Suzhou Zoo.
It’s the team’s sixth year of breeding the turtles at the zoo, which is not far from Shanghai. So far, none of the eggs have hatched.
Researchers can’t pinpoint the reason for the infertility, but they suspect a combination of factors, including poor sperm quality due to the male’s age—roughly a hundred—an improper mating posture, and stress on the female.
Because the turtles are the last in captivity and too much human interaction could kill them, sperm samples cannot be taken nor tests run. Still, scientists are hoping that this year will be the lucky one. (Related: "Pictures: Turtles Hunted, Traded, Squeezed Out of Their Habitats.")
"The resurrection of this iconic species in the wild, the largest freshwater turtle in the world, would be a symbol of hope," said Gerald Kuchling, founder of the Australia-based group Turtle Conservancyand a turtle-reproduction expert.
"Miraculous" Find
As is the case with many near-extinct species, by the time scientists realized the extent of the turtle’s decline, the species was almost gone.
In 2006, the U.S. nonprofit Turtle Survival Alliance asked Kuchling to establish the sex of the last three captive giant softshell turtles in China, which at the time lived at the Shanghai Zoo, Suzhou Zoo, and Suzhou’s West Garden Buddhist Temple. (Related: “6 of Nature’s Loneliest Animals Looking for Love.”)
When Kuchling landed in China in 2007, the Shanghai Zoo and Buddhist Temple individuals had already died. The Suzhou Zoo male was the last known Chinese survivor. Researchers sent an all-points bulletin to every zoo in the nation in the off chance a turtle had been misidentified.
Their call was answered: A photograph of a turtle at the Changsha Zoo looked promising. Kuchling, along with Lu Shunqing, China director for the Wildlife Conservation Society, traveled to Changsha, where they confirmed it was a Yangtze giant softshell—and a female to boot.
"It’s a bit miraculous we found her," said Emily King, the Suzhou Zoo breeding program’s field assistant.
read more from NatGeo 

World’s Largest Freshwater Turtle Nearly Extinct

The last known pair of Yangtze giant softshell turtles mated again in June.

Kaitlin Solimine

for National Geographic

PUBLISHED JULY 1, 2013

The fate of a species is resting on the shells of two turtles at China's Suzhou Zoo.

n June, researchers collected eggs from the last mating pair of the critically endangered Yangtze giant softshell turtle (Rafetus swinhoei) in the hopes that at least one will be fertile.

The 220-pound (100-kilogram) freshwater giant, which spends most of its life burrowing in mud, was once common in its namesake Yangtze River, China’s Lake Taihu and Yunnan Province, and parts of Vietnam.

By the late 1990s, however, human encroachment and poaching for use of the shells in Chinese traditional medicine rapidly depleted the population. Now, a total of four animals are known—two wild males in Vietnam and the mating pair at Suzhou Zoo.

It’s the team’s sixth year of breeding the turtles at the zoo, which is not far from Shanghai. So far, none of the eggs have hatched.

Researchers can’t pinpoint the reason for the infertility, but they suspect a combination of factors, including poor sperm quality due to the male’s age—roughly a hundred—an improper mating posture, and stress on the female.

Because the turtles are the last in captivity and too much human interaction could kill them, sperm samples cannot be taken nor tests run. Still, scientists are hoping that this year will be the lucky one. (Related: "Pictures: Turtles Hunted, Traded, Squeezed Out of Their Habitats.")

"The resurrection of this iconic species in the wild, the largest freshwater turtle in the world, would be a symbol of hope," said Gerald Kuchling, founder of the Australia-based group Turtle Conservancyand a turtle-reproduction expert.

"Miraculous" Find

As is the case with many near-extinct species, by the time scientists realized the extent of the turtle’s decline, the species was almost gone.

In 2006, the U.S. nonprofit Turtle Survival Alliance asked Kuchling to establish the sex of the last three captive giant softshell turtles in China, which at the time lived at the Shanghai Zoo, Suzhou Zoo, and Suzhou’s West Garden Buddhist Temple. (Related: “6 of Nature’s Loneliest Animals Looking for Love.”)

When Kuchling landed in China in 2007, the Shanghai Zoo and Buddhist Temple individuals had already died. The Suzhou Zoo male was the last known Chinese survivor. Researchers sent an all-points bulletin to every zoo in the nation in the off chance a turtle had been misidentified.

Their call was answered: A photograph of a turtle at the Changsha Zoo looked promising. Kuchling, along with Lu Shunqing, China director for the Wildlife Conservation Society, traveled to Changsha, where they confirmed it was a Yangtze giant softshell—and a female to boot.

"It’s a bit miraculous we found her," said Emily King, the Suzhou Zoo breeding program’s field assistant.

read more from NatGeo 

Ashik Gavai had a benign tumour in his mouth that causes additional teeth to grow: http://bit.ly/1pOIUAj
through SA

Ashik Gavai had a benign tumour in his mouth that causes additional teeth to grow: http://bit.ly/1pOIUAj

through SA

How Dying Works

by 

The Dying Process

As technology helps us to live longer, it will also shape how we die. With a higher-brain definition of death, you’re gone when your personality is. With a whole-brain definition of death, you’ve lost the ability to breathe on your own again. Each breath provides the oxygen necessary for survival to the rest of the body. Very simply, dying starts to happen when your body doesn’t get the oxygen it needs to survive.

Different cells die at different speeds, so the length of the dying process depends on which cells are deprived of oxygen. The brainrequires a tremendous amount of oxygen but keeps very little in reserve, so any cutoff of oxygen to the brain will result in cell death within three to seven minutes; that’s why a stroke can kill so quickly. When blood is cut off from the heart, a heart attack occurs and can also take a life fairly swiftly. But since our bodies aren’t designed to last forever, sometimes the body’s systems just simply wear out. When someone dies of extremely old age, and the family is gathered around the deathbed, you’re basically observing the breakdown of these systems.

There are some outward signs that these systems are slowing down. The person will begin sleeping more to conserve the little energy that’s left. When that energy is gone, the individual may lose the desire to eat and then to drink. Swallowing becomes difficult and the mouth gets very dry, so forcing the person to eat or drink could cause choking. The dying person loses bladder and bowel control, but accidents will occur less frequently as those gastrointestinal functions shut down as well and he or she consumes less.

Any ­pain that the dying person feels at this point can usually be managed by a doctor in some way, but it can be unbelievably difficult to watch these final steps of a person’s life. The stage right before a person dies is called the agonal phase. The dying person is often disoriented, and it will seem like he or she can’t get comfortable. It will also seem, disconcertingly, that the person can’t catch a breath. There may be agonizing pauses between loud, labored breaths. If there is fluid built up in the lungs, then that congestion will cause a sound known as the death rattle. As the cells inside a person lose their connections, the person may start convulsing or having muscle spasms.

We can’t know exactly how the person is feeling at this point, though those who have had near-death experiences (NDE) seem to agree that the process isn’t painful. NDEs appear to have some common characteristics, including a feeling of peace and well-being, a sense of separation from the physical body and a sensation of walking through darkness to enter light. You can read more about NDEs in How Near-death Experiences Work.

Some doctors think that a near-death experience might be due to endorphins that the body releases at the actual moment of death [source: Nuland]. When the heartbeat and breath stop, the person is clinically dead. There’s no circulation, and no new reserves of oxygen are reaching cells. However, clinical death also denotes that this is a point where the process is reversible, by means of CPR, a transfusion or a ventilator.

The point of no return is biological death, which begins about four to six minutes after clinical death. After the heartbeat stops, it only takes that long for brain cells to begin dying from lack of oxygen. Resuscitation is impossible at this point.

What you think has happened to the essence of the person at this point is dependent on your religious and cultural beliefs. But as our examination of the postmortem body on the next page will reveal, there’s not a lot of time for sitting around and staring at the corpse.

read more from HowStuffWorks

photo one is  Death nature with shooting gear and flowers I by Jean Baptiste Oudry through wiki 

the second is Death of Cato by Gioacchino Assereto through wiki

Image of the Day:Cryptococcus neoformans giant cell.WOW! Isn’t this scanning electron micrograph incredible?This C. neoformans giant cell was isolated from the lung of an infected mouse. Illustrated here is a characteristic phenotypic feature of giant cells: a high density of polysaccharide fibers present in the capsule in a compact, cross-linked net around the cell body. Image credit: Oscar Zaragoza. PLoS Pathogens, 2010. doi: 10.1371/image.ppat.v06.i06
source 

Image of the Day:
Cryptococcus neoformans giant cell.

WOW! Isn’t this scanning electron micrograph incredible?
This C. neoformans giant cell was isolated from the lung of an infected mouse. Illustrated here is a characteristic phenotypic feature of giant cells: a high density of polysaccharide fibers present in the capsule in a compact, cross-linked net around the cell body. 

Image credit: Oscar Zaragoza. PLoS Pathogens, 2010. doi: 10.1371/image.ppat.v06.i06

source 

Tags: science cells