10 Reasons to Stop Eating Beef (and other Fast Food)

by Jonathan Campbell
Beef-eating is portrayed in the U.S. almost as a patriotic endeavor. Our favorite sports heroes - from Michael Jordan to Drew Bledsoe - are featured in McDonalds ads and toys. We are literally bombarded with ads for McDonalds, Burger King, and Wendy's. But there is something very odd about all this. There are hints (or front page headlines) telling us that there is something wrong with all this beef consumption.
In fact, a quick study of the issues surrounding beef consumption finds some very disturbing facts:
1. Beef contains significant quantities of the most toxic organic chemical known - dioxin. This chemical is toxic in the trillionths of grams. (A trillionth of a gram, called a picogram, is one million millionth of a gram. A gram is about 1/30th of an ounce.) Dioxin has been linked to cancer, endometriosis, Attention Deficit Disorder (hyperactivity in children), reproductive systems defects in children, chronic fatigue syndrome, immune system deficiency, and rare nerve and blood disorders. A single hamburger (a little less than 1/4 lb, or 100 grams) contains up to 100 picograms of dioxin. That is 300 times as much as the EPA says is "acceptable" for a daily dose for an adult! There are some scientists who say that there is no acceptable dose; they say that any dose can cause toxic effects, because dioxin is a hormone disrupting chemical which changes the functioning of our cells, against which we have no defense. The dioxin comes from microscopic particles of ash from incinerators that have settled on grass and crops eaten by the beef cattle, pigs, and chickens. All farm animals are affected - even herds grown on "all-natural" feed. See dioxin.
2. The huge amount of beef that we consume, in combination with the usual side-orders of other fatty foods (such as french fries) and caffeine and refined sugars (cola beverages) appears to be one of the major causes of obesity in the U.S. and Europe. Beef is "dumped" into our schools by the beef industry and the USDA - beef producers are paid by the government for "surplus" beef (the vast amount they cannot sell) which is subsequently "donated" to school lunch programs, helping our children to get hooked on this unhealthy food.
3. Beef production is the major cause of the destruction of the world's rainforests. The high price of beef encourages ranchers to burn the forest to create new rangelands. The fragile, thin rainforest soil cover is quickly destroyed by grazing in 1-2 years, and the ranchers move on to burn another area, in a never-ending cycle of destruction. Thousands of species of plants and animals have already been destroyed forever, as well as straining the earth's ability to convert carbon dioxide into oxygen. At current rates, the rainforests will be totally destroyed in 30-50 years.
4. Beef production is the major cause of "desertification" around the world - the rapid degradation of marginal, low-rainfall soil areas into desert. The constant pounding of the hoofs of cattle disturbs and eventually destroys the delicate root systems which keep the topsoil layer intact. Erosion by winds or storms removes the topsoil, leaving the sand or clay subsoil layer behind.
5. Beef production is a serious social justice issue. Beef cattle and their grazing land take up nearly a quarter of the land mass of the earth, to supply beef to the U.S., Europe, and Japan. About one third of the world's grain harvest is used for feed for cattle instead of food for people. In the U.S., that figure is over 70 percent. It takes 16 pounds of grain to produce a single pound of beef. This, in a world where nearly a billion people lack enough food, is unjust. Beef production for the developed parts of the world is severely limiting the amount of food available for people in the poor and developing world.
6. Beef can harbor a deadly new germ, called e. coli O157:H7. This new germ is now a major cause of serious food poisoning. Beef and dairy cattle can carry the germ with no apparent adverse health effects. The germ, found in cattle feces, has contaminated beef and produce grown with cow manure. So far it has killed dozens of people and sickened thousands. In August, 1997, 25 million pounds of beef were recalled, the largest food recall in the world's history, because of O157:H7 contamination of beef destined to Burger King restaurants. The precautions against the germ - including cooking to 160º F (71º C) - reveals a disgusting side of beef production - there is no way to prevent fecal contamination during slaughter. See O157:H7.
7. The consumption of beef and fast food "restaurants" that promote it have created a new, super-exploitative work environment. High school students and people in poverty have learned an old social order - the sweatshop. The frenetic pace of a McDonalds or Burger King at lunch or dinner time is easily a match for the non-unionized factories and garment shops of the '20s in the U.S. (or most developing countries today). But this is the modern U.S. sweatshop, where we are all members of a "team" working for the common good - minimum wages and windfall profits.
8. Beef consumption has created a self-perpetuating and rapidly-expanding distortion of local economies all over the world. As more McDonalds "restaurants" are established and beef consumption rises, more arable land is consumed for grazing and cattle feed. In developing countries, the local economy changes from one based on local food markets and trade to one based on beef exports, enriching a few wealthy landowners and merchants and impoverishing the rest.
9. The "fast-food" industry giants that promote beef - McDonalds, Burger King, and Wendy's - have created and encouraged an artificial, plastic, uniform, standard "restaurant" environment that, because of their powerful advertising media, discourages diversity and local and ethnic culture in restaurants and in food choices. Beef - served as hamburgers - has been the driving force for this shift in how we view food and eating in the U. S.
10. The beef "fast-food" industry, notably McDonalds and Burger King, especially targets children in its marketing. As a result, millions of children (and in many cases, their parents) associate eating at those "restaurants" as a fun, positive, healthful eating experience. Obesity and other afflictions associated with excess animal fat intake and sedentary lifestyle are now affecting young adults and children in increasing numbers.
Sources: 1994 EPA Dioxin Reassessment, Dying From Dioxin by Lois Gibbs, Beyond Beef by Jeremy Rifkin, fact sheets from the McLibel case (Great Britain), Diet For A Small Planet by Francis Moore Lappe, Mother Jones magazine.

New genus of bacteria found living inside hydraulic fracturing wells

Ohio State University researchers and their colleagues have identified a new genus of bacteria living inside hydraulic fracturing wells. These jars contain samples of "produced water fluids" -- the fluid that is collected at the surface of a hydraulic fracturing well after fracturing -- from wells in Marcellus and Utica shale formations. The fluids are orange because they contain large amounts of iron that oxidizes when the fluids are brought to the surface. By analyzing the genomes of microbes in the water, the researchers are piecing together the existence of microbial communities inside the wells.

Credit: Photo by Rebecca Daly, courtesy of The Ohio State University.

Researchers analyzing the genomes of microorganisms living in shale oil and gas wells have found evidence of sustainable ecosystems taking hold there -- populated in part by a never-before-seen genus of bacteria they have dubbed "Frackibacter."

The new genus is one of the 31 microbial members found living inside two separate fracturing wells, Ohio State University researchers and their colleagues report in the Sept. 5 online edition of the journal Nature Microbiology.

Even though the wells were hundreds of miles apart and drilled in different kinds of shale formations, the microbial communities inside them were nearly identical, the researchers discovered.

Almost all the microbes they found had been seen elsewhere before, and many likely came from the surface ponds that energy companies draw on to fill the wells. But that's not the case with the newly identified Candidatus Frackibacter, which may be unique to hydraulic fracturing sites, said Kelly Wrighton, assistant professor of microbiology and biophysics at Ohio State.

In biological nomenclature, "Candidatus" indicates that a new organism is being studied for the first time using a genomic approach, not an isolated organism in a lab culture. The researchers chose to name the genus "Frackibacter" as a play on the word "fracking," shorthand for "hydraulic fracturing."

Candidatus Frackibacter prospered alongside the microbes that came from the surface, forming communities in both wells which so far have lasted for nearly a year.

"We think that the microbes in each well may form a self-sustaining ecosystem where they provide their own food sources," Wrighton explained. "Drilling the well and pumping in fracturing fluid creates the ecosystem, but the microbes adapt to their new environment in a way to sustain the system over long periods."

By sampling fluids taken from the two wells over 328 days, the researchers reconstructed the genomes of bacteria and archaea living in the shale. To the researchers' surprise, both wells -- one drilled in Utica shale and the other drilled in Marcellus shale -- developed nearly identical microbial communities.

In addition, the two wells are each owned by different energy companies that utilized different fracturing techniques. The two types of shale exist more than a mile and a half below ground, were formed millions of years apart, and contained different forms of fossil fuel. Yet one bacterium, Halanaerobium, emerged to dominate communities in both wells.

"We thought we might get some of the same types of bacteria, but the level of similarity was so high it was striking. That suggests that whatever's happening in these ecosystems is more influenced by the fracturing than the inherent differences in the shale," Wrighton said.

Wrighton and her team are still not 100 percent sure of the microbes' origins. Some almost undoubtedly came from the ponds that provide water to the wells, she said. But other bacteria and archaea could have been living in the rock before drilling began,Candidatus Frackibacter among them.

Shale energy companies typically formulate their own proprietary recipes for the fluid they pump into wells to break up the rock and release oil or gas, explained Rebecca Daly, research associate in microbiology at Ohio State and lead author of the Nature Microbiology paper. They all start with water and add other chemicals. Once the fluid is inside a well, salt within the shale leaches into it, making it briny.

The microorganisms living in the shale must tolerate high temperature, pressure and salinity, but this study suggests that salinity is likely the most important stressor on the microbes' survival. Salinity forces the microbes to synthesize organic compounds called osmoprotectants to keep themselves from bursting. When the cells die, the osmoprotectants are released into the water, where other microbes can use them for protection themselves or eat them as food. In that way, salinity forced the microbes to generate a sustainable food source.

In addition to the physical constraints in the environment, the microbes also must protect themselves from viruses. The researchers reconstructed the genomes of viruses living inside the wells, and found genetic evidence that some bacteria were indeed falling prey to viruses, dying, and releasing osmoprotectants into the water.

By examining the genomes of the different microbes, the researchers found that the osmoprotectants were being eaten byHalanaerobium and Candidatus Frackibacter. In turn, these bacteria provided food for other microbes called methanogens, which ultimately produced methane.

To validate their findings from the field, the researchers grew the same microbes in the lab under similar conditions. The lab-grown microbes also produced osmoprotectants that were converted into methane -- a confirmation that the researchers are on the right track to understanding what's happening inside the wells.

One implication of the study is that methane produced by microbes living in shale wells could possibly supplement the wells' energy output.

Wrighton and Daly described the amount of methane produced by the microbes as likely minuscule compared to the amount of oil and gas harvested from the shale even a year after initial fracturing. But, they point out, there is a precedent in a related industry, that of coal-bed methane, to use microbes to greater advantage.

"In coal-bed systems they've shown that they can facilitate microbial life and increase methane yields," Wrighton said. "As the system shifts over time to being less productive, the contribution of biogenic methane could become significantly higher in shale wells. We haven't gotten to that point yet, but it's a possibility."

In the meantime, research led by co-author Michael Wilkins, assistant professor of earth sciences and microbiology, has used genomics information to grow Candidatus Frackibacter in the lab and is further testing its ability to handle high pressure and salinity.

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The above post is reprinted from materials provided by Ohio State University. The original item was written by Pam Frost Gorder. Note: Content may be edited for style and length.

Bacteria supply their allies with munitions

Vibrio cholerae bacteria (green) recycle T6SS proteins of the attacking sister cells (red) to build their own spear gun (light green intracellular structure).

Credit: University of Basel

Many bacteria possess molecular spear guns, which they fire at enemies and rivals, thus putting them out of action. The tips of these nano-spear guns, known as Type VI secretion system (T6SS), are loaded with toxic molecules that lead to death of their adversaries. However, sometimes close related bacteria come under fire.

The team of Prof. Marek Basler, infection biologist at the Biozentrum of the University of Basel, has shown for the first time, that in contrast to their enemies the harpooned sister cells actually profit from the attack: After a T6SS injection, they are able to reuse specific proteins to produce their own spear guns. Thus the related bacterial strains help each other to enlarge their arsenal of weapons and to fight their competitors.

Bacteria harpoon their opponents -- and their allies

The T6SS is firmly attached to the bacterial cell envelop. The tiny spear with a sharp tip is surrounded by a flexible sheath. "When bacteria fire their spear guns, the sheath rapidly contracts in just a few milliseconds and ejects the spear out of the cell into by-standing bacteria," says Basler describing the mechanism. "The attackers then recycle the harpoon proteins remaining in the cell." In this maneuver, the bacteria also hit related bacterial strains that do the same as the attackers: They disassemble the harpoon into their protein components and reuse these for new T6SS assembly.

Recycling is everything: Bacteria also provide unarmed allies with munitions

That closely related bacteria share their proteins through this type of spear gun attack and then recycle the components, has been demonstrated by the researchers for the first time, using the cholera pathogen, Vibrio cholerae. For this, they mixed T6SS-deficient bacteria that lack the proteins needed for the spear gun production with normal T6SS-producing Vibrio bacteria. "The special thing about Vibrio cholerae is that it assembles spear guns all the time and fires them aimlessly," explains Andrea Vettiger, author of the study. "If one of T6SS-defecient bacteria is randomly hit, it disassembles the spear gun to its individual components, the shaft and tip proteins, and reassembles its own functional harpoon.

Also the translocated tip-linked toxins can be recycled by the attacked cell. And even bacteria that no longer produce any proteins can assemble a T6SS by reusing the harpooned proteins provided by their neighboring sister cells."

Bacteria fight together against competitors

Additionally, the researchers observed the related bacterial strains also cooperate with each other and join forces in their defense against undesirable rivals. Thus, two Vibrio strains can cooperate to kill a third competitor, even if one of them lacks individual T6SS components or the toxins for the spear tip. They combine their resources and produce their weapons together. "Although we have only observed this interbacterial complementation under laboratory conditions, we are convinced that this form of cooperation plays an important role in nature and provides some bacterial communities with a survival advantage," says Basler.

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A tenth of the world's wilderness lost since the 1990s

Researchers reporting in the journal Current Biology show catastrophic declines in wilderness areas around the world over the last 20 years.

Credit: Liana Joseph

Researchers reporting in the journal Current Biology show catastrophic declines in wilderness areas around the world over the last 20 years. They demonstrate alarming losses comprising a tenth of global wilderness since the 1990s -- an area twice the size of Alaska and half the size of the Amazon. The Amazon and Central Africa have been hardest hit.

The findings underscore an immediate need for international policies to recognize the value of wilderness areas and to address the unprecedented threats they face, the researchers say.

"Globally important wilderness areas -- despite being strongholds for endangered biodiversity, for buffering and regulating local climates, and for supporting many of the world's most politically and economically marginalized communities -- are completely ignored in environmental policy," says Dr James Watson of the University of Queensland in Australia and the Wildlife Conservation Society in New York. "Without any policies to protect these areas, they are falling victim to widespread development. We probably have one to two decades to turn this around. International policy mechanisms must recognize the actions needed to maintain wilderness areas before it is too late. We probably have one to two decades to turn this around."

Watson says much policy attention has been paid to the loss of species, but comparatively little was known about larger-scale losses of entire ecosystems, especially wilderness areas which tend to be relatively understudied. To fill that gap, the researchers mapped wilderness areas around the globe, with "wilderness" being defined as biologically and ecologically intact landscapes free of any significant human disturbance. The researchers then compared their current map of wilderness to one produced by the same methods in the early 1990s.

This comparison showed that a total of 30.1 million km2 (around 20 percent of the world's land area) now remains as wilderness, with the majority being located in North America, North Asia, North Africa, and the Australian continent. However, comparisons between the two maps show that an estimated 3.3 million km2(almost 10 percent) of wilderness area has been lost in the intervening years. Those losses have occurred primarily in South America, which has experienced a 30 percent decline in wilderness, and Africa, which has experienced a 14 percent loss.

"The amount of wilderness loss in just two decades is staggering" Dr Oscar Venter of the University of Northern British Colombia. "We need to recognize that wilderness areas, which we've foolishly considered to be de-facto protected due to their remoteness, is actually being dramatically lost around the world. Without proactive global interventions we could lose the last jewels in nature's crown. You cannot restore wilderness, once it is gone, and the ecological process that underpin these ecosystems are gone, and it never comes back to the state it was. The only option is to proactively protect what is left."

Watson says that the United Nations and others have ignored globally significant wilderness areas in key multilateral environmental agreements and this must change.

"If we don't act soon, there will only be tiny remnants of wilderness around the planet, and this is a disaster for conservation, for climate change, and for some of the most vulnerable human communities on the planet," Watson says. "We have a duty to act for our children and their children."

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With MRI technique, brain scientists induce feelings about faces

Volunteers who started an experiment feeling neutral about certain faces they saw ended up unknowingly adopting the feelings that scientists induced via an MRI feedback technique, according to newly published research.

The study in PLO

Credit: deviantart

S Biology therefore suggests that there is a single region of the brain where both positive and negative feelings for faces take shape and provides the second demonstration this year that the MRI technique can be used to train a mental process in an unknowing subject. This spring, the team used the same method to associate the perception of color with the context of a pattern so strongly that volunteers saw the color when cued by the pattern, even if the color wasn't really there.

In the new study, the researchers sought to determine whether they could direct feelings about faces -- a more sophisticated brain function that is closer to their eventual goal, which is to develop the technique to the point where it could become a tool for psychological therapy, for instance for anxiety.

"Face recognition is a very important social function for people," said co-author Takeo Watanabe, the Fred M. Seed Professor of Cognitive and Linguistic Sciences at Brown University. "Facial recognition is associated with people's emotions."

Decoded neurofeedback explained

The technique, which the researchers call "DecNef," for decoded neurofeedback, starts with detecting and analyzing the specific activity patterns in a brain region that correspond to a mental state. For example, at the beginning of the new study, while 24 volunteers saw hundreds of faces and rated their sentiments about each of them (on a scale of 1 for dislike to 10 for like, with 5 for neutral), the researchers used MRI to record the patterns of activity in a brain region called the cingulate cortex.

That step alone was fairly conventional neuroscience except that many scientists believe that positive or negative feelings about faces are formulated in separate brain regions. But this team of four researchers at Brown University and the Advanced Telecommunications Research Institute International in Kyoto, Japan, wanted to test whether the cingulate cortex handles both sides of the emotion.

Sure enough, the researchers' software, called a decoder, was able to analyze the recordings to identify reliable and distinct patterns in each volunteer's cingulate cortex associated with positive and negative feelings about faces.

"We found that the cingulate cortex seems to handle both opposing directions with different activity patterns," said co-author Yuka Sasaki, associate professor (research) of cognitive, linguistic and psychological sciences at Brown.

With these signature patterns established for each volunteer, the participants were then unknowingly divided into two groups of 12 -- either positive or negative -- and were called back in for a few days of additional research in the MRI machine. In this phase the subjects were shown a subset of the faces they rated as neutral and were then asked to perform a seemingly unrelated task: After seeing each face on the screen, they were then shown a disk and asked to somehow use their minds to try to make it appear as big as possible. The bigger they could make the disk, they were told, the more of a small monetary reward they could receive.

In reality, the tasks weren't unrelated. Participants didn't know this at the time, but the only way the disk would grow was when the MRI readings showed that they happened (for whatever reason) to produce their signature patterns of positive or negative feelings about faces in their cingulate cortex. In other words, the experiment rewarded volunteers in the positive group with a larger disk when they produced the pattern associated with liking the faces after seeing a previously neutral one. Similarly, the experiment rewarded volunteers in the negative group with a growing disk the more they happened to produce the pattern associated with dislike after seeing a neutral one.

In essence, DecNef aims to train people to produce specific feelings or perceptions in specific contexts by rewarding those moments when they unknowingly do so.

A third group of six other participants was used as a control group. They saw faces and rated them, but were not given the DecNef step of having to enlarge a disk in association with the activation patterns that represent positive or negative feelings.

Finally, all the participants were then queried anew about their feelings regarding the initially neutral faces.

Facial feelings were affected

When the researchers analyzed the results, they were able to make several key findings. On average, the positive group's ratings of the neutral faces moved up mildly but significantly (by about 0.6 on the 1 to 10 scale), while the negative group's ratings of the faces moved down a bit less but still significantly. Meanwhile the control group's ratings didn't change significantly at all.

"From all these results we conclude that association of originally neutrally rated faces with covert induction of activity patterns in the single brain region, the cingulate cortex, led to changes in facial preference specifically for those faces, and in a specific preference -- positive or negative -- direction," the authors wrote in the study.

To be as certain as possible about the findings, they did a few more analyses. In post-experiment interviews, they asked the subjects whether they knew what was really going on -- none did. Then the researchers explained what the experiment was really about and asked people to say whether they thought they were in the positive or negative group. People were no better than chance at saying which they were in. Together these results suggest that none of the experimental volunteers changed their preferences about neutral faces based on their own will or intention.

In another analysis, the researchers crunched the numbers to see if the degree of activity in the cingulate cortex during the disk-enlargement phase correlated with the degree of change in preferences. The results revealed a high correlation (0.78 out of 1). In other words, the amount of brain activity was proportional to the amount of induced feeling.

Toward a DecNef therapy

While the induced changes in feeling were mild, the training took place over only a few days, the researchers noted. Training that occurs on the scale of weeks, as is often required for clinical therapies, might have induced stronger feelings.

But even a small effect could be beneficial for people if it blunts a persistently painful feeling associated with a certain trigger, Watanabe said.

"If someone develops a traumatic memory that makes him or her suffer, even a small reduction of the suffering would be helpful," Watanabe said.

The researchers also said they are aware that there could be potential abuse or misuse of the technique -- a kind of brainwashing -- so it might be good if it proves at least somewhat limited in its effect.

In addition to Sasaki and Watanabe, the paper's other authors are lead author Kazuhisa Shibata and corresponding author Mitsuo Kawato.

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Journal Reference:

1. Kazuhisa Shibata, Takeo Watanabe, Mitsuo Kawato, Yuka Sasaki. Differential Activation Patterns in the Same Brain Region Led to Opposite Emotional States. PLOS Biology, 2016; 14 (9): e1002546 DOI:10.1371/journal.pbio.1002546

Placenta in females, muscle mass in males: Dual heritage of a virus

Cross section of mouse muscle (in blue: labeling of nuclei; in green: labeling of muscle fiber membranes). Normal male mice display larger muscle fibers than those seen in mutant, syncytin knock-out mice.

Credit: François Redelsperger

University of Tsukuba,

It was already known that genes inherited from ancient retroviruses[1] are essential to the placenta in mammals, a finding to which scientists in the Laboratoire Physiologie et Pathologie Moléculaires des Rétrovirus Endogènes et Infectieux (CNRS/Université Paris-Sud) contributed. Today, the same scientists[2] have revealed a new chapter in this astonishing story: these genes of viral origin may also be responsible for the more developed muscle mass seen in males! Their findings are published on 2 September 2016 in PLOS Genetics.

Retroviruses carry proteins on their surface that are able to mediate fusion of their envelope with the membrane of a target cell. Once released inside that cell, their genetic material becomes integrated in the host's chromosomes. In the rare cases where the infected cell is involved in reproduction, the viral genes may be transmitted to progeny. Thus nearly 8% of the mammalian genome is made up of vestiges of retroviruses, or "endogenous" retroviruses. Most of them are inactive, but some remain capable of producing proteins: this is the case of syncytins, proteins that are present in all mammals and encoded by genes inherited from retroviruses "captured" by their ancestors. A little more than five years ago, and thanks to inactivation of these genes in mice, the team led by Thierry Heidmann demonstrated that syncytins contribute to formation of the placenta. Because of their ancestral ability to mediate cell-cell fusion they give rise to the syncytiotrophoblast[3], a tissue formed by the fusion of a large number of cells derived from the embryo, at the fetomaternal interface.
Using the same mice, the team has revealed a "collateral" and unexpected effect of these proteins: they endow males with more muscle mass than females! Like the syncytiotrophoblast, muscle mass develops from fused stem cells. In the genetically-modified male mice, these fibers were 20% smaller and displayed 20% fewer nuclei than in standard males; they were then similar to those seen in females, as was their total muscle mass. It therefore appears that the inactivation of syncytins leads to a fusion deficit during muscle growth, but only in males. The scientists observed the same phenomenon in the case of muscle regeneration following a lesion: the male mice incapable of producing syncytins experienced less effective regeneration than the other males, but it was comparable to that seen in females. Furthermore, the regenerating muscle fibers produced syncytin -- once again, only in males.
If this discovery were to be confirmed in other mammals, it might account for the muscle dimorphism observed between males and females, a difference that is not seen so systematically in egg laying animals. By cultivating muscle stem cells from different mammalian species (mouse, sheep, dog, human), the scientists have advanced some way along the path: they indeed showed that syncytins contributed to the formation of muscle fibers in all the species tested. It is now necessary to demonstrate whether, in these species as well, the action of syncytins is also male-specific.
[1] The particular feature of retroviruses is that they possess an enzyme that permits transcription of their RNA genome in a "complementary" DNA molecule which is able to integrate in the DNA of the host cell. The AIDS virus (HIV) is the best known example of a retrovirus.
[2] In collaboration with colleagues working on muscles: the teams led by Julie Dumonceaux at the Centre de Recherche en Myologie (CNRS/UPMC/Inserm) and Laurent Tiret at the École Nationale Vétérinaire d'Alfort and the Institut Mondor de Recherche Biomédicale (Inserm/UPEC).
[3] The syncytiotrophoblast is part of the placenta that permits implantation in the uterus and then constitutes the interface between the maternal bloodstream and that of the embryo, where the exchanges of gases and nutrients necessary for the latter's development occur.

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How Moon was formed ??

This image shows from left Paul Warren, Edward Young and Issaku Kohl. Young is holding a sample of a rock from the moon.

Credit: Christelle Snow/UCLA

Moon was produced by a head-on collision between Earth and a forming planet: Research reconstructs massive crash, which took place 4.5 billion years ago

 

Science and Technology Facilities Council,

The moon was formed by a violent, head-on collision between the early Earth and a "planetary embryo" called Theia approximately 100 million years after the Earth formed, UCLA geochemists and colleagues report.

Scientists had already known about this high-speed crash, which occurred almost 4.5 billion years ago, but many thought the Earth collided with Theia (pronounced THAY-eh) at an angle of 45 degrees or more -- a powerful side-swipe (simulated in this 2012 YouTube video). New evidence reported Jan. 29 in the journal Science substantially strengthens the case for a head-on assault.
The researchers analyzed seven rocks brought to the Earth from the moon by the Apollo 12, 15 and 17 missions, as well as six volcanic rocks from the Earth's mantle -- five from Hawaii and one from Arizona.
The key to reconstructing the giant impact was a chemical signature revealed in the rocks' oxygen atoms. (Oxygen makes up 90 percent of rocks' volume and 50 percent of their weight.) More than 99.9 percent of Earth's oxygen is O-16, so called because each atom contains eight protons and eight neutrons. But there also are small quantities of heavier oxygen isotopes: O-17, which have one extra neutron, and O-18, which have two extra neutrons. Earth, Mars and other planetary bodies in our solar system each has a unique ratio of O-17 to O-16 -- each one a distinctive "fingerprint."
In 2014, a team of German scientists reported in Science that the moon also has its own unique ratio of oxygen isotopes, different from Earth's. The new research finds that is not the case.
"We don't see any difference between the Earth's and the moon's oxygen isotopes; they're indistinguishable," said Edward Young, lead author of the new study and a UCLA professor of geochemistry and cosmochemistry.
Young's research team used state-of-the-art technology and techniques to make extraordinarily precise and careful measurements, and verified them with UCLA's new mass spectrometer.
The fact that oxygen in rocks on the Earth and our moon share chemical signatures was very telling, Young said. Had Earth and Theia collided in a glancing side blow, the vast majority of the moon would have been made mainly of Theia, and the Earth and moon should have different oxygen isotopes. A head-on collision, however, likely would have resulted in similar chemical composition of both Earth and the moon.
"Theia was thoroughly mixed into both the Earth and the moon, and evenly dispersed between them," Young said. "This explains why we don't see a different signature of Theia in the moon versus the Earth."
Theia, which did not survive the collision (except that it now makes up large parts of Earth and the moon) was growing and probably would have become a planet if the crash had not occurred, Young said. Young and some other scientists believe the planet was approximately the same size as the Earth; others believe it was smaller, perhaps more similar in size to Mars.
Another interesting question is whether the collision with Theia removed any water that the early Earth may have contained. After the collision -- perhaps tens of millions of year later -- small asteroids likely hit the Earth, including ones that may have been rich in water, Young said. Collisions of growing bodies occurred very frequently back then, he said, although Mars avoided large collisions.
A head-on collision was initially proposed in 2012 by Matija ?uk, now a research scientist with the SETI Institute, and Sarah Stewart, now a professor at UC Davis; and, separately during the same year by Robin Canup of the Southwest Research Institute.
Co-authors of the Science paper are Issaku Kohl, a researcher in Young's laboratory; Paul Warren, a researcher in the UCLA department of Earth, planetary, and space sciences; David Rubie, a research professor at Germany's Bayerisches Geoinstitut, University of Bayreuth; and Seth Jacobson and Alessandro Morbidelli, planetary scientists at France's Laboratoire Lagrange, Université de Nice.
The research was funded by NASA, the Deep Carbon Observatory and a European Research Council advanced grant (ACCRETE).

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The above post is reprinted from materials provided by University of California - Los Angeles. The original item was written by Stuart Wolpert. Note: Content may be edited for style and length.