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Rakesh Yadav
Worked at Indian Institute of technology, Kanpur, India
Attends Georg-August University of Göttingen
Lives in Goettingen, germany
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Rakesh Yadav

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Recently a review article (http://goo.gl/wByL46; open access) was shared by +Jim Carver .  The article had a somewhat provocative title "Can We Say What Diet Is Best for Health?" and I was sucked into the trap.

Such review articles are very important as they try to paint a comprehensive picture of the field of research and ideally provide an un-biased analysis of the different studies conducted in the past. In lack of such articles a non-expert can easily be lost in the myriad of studies, sometimes reporting conflicting results. Anyway, I read the abstract, and then the introduction and then the whole thing. I found it very interesting and hence I am sharing the main points (from my perspective). The summary below is mostly a copy-paste text from the original article with some paraphrasing done for the sake of coherence. This is of course in no way a comprehensive summary. If you are intrigued by some aspects, then you should definitely read the article! 

The authors basically talk about popular dietary choices in current culture. Using scientific studies they try to narrow down on health-promoting foods. They examine 7 diets which are described below.

[Warning: brace yourself, a long one is coming]

Summary starts here 
-----------------------------------------------
Low carb diet 
Definition: total daily carbohydrate intake below 45% of total calories.

Interest in carbohydrate-restricted diets is long-standing, particularly in the context of diabetes management, and especially during the era before the advent of insulin therapy. It has become popular again in the context of weight control. Short to moderate intervention studies have shown efficacy in weight loss and favorably effects for quality of life. No long term intervention studies exist. Such studies cannot and do not, however, unbundle the effects of (a) carbohydrate restriction per se, on which the theory of the approach is predicated, and (b) calorie restriction, which is a virtually inevitable concomitant of choice restriction in general, and, perhaps especially, (c) restriction directed at carbohydrate, which constitutes the macronutrient class that provides the majority of calories for almost all omnivorous species. 

The basic principle for the diet is very general. For example the remaining calories can come from fat or protein, and, furthermore, these calories can be of plant of animal origin. The authors sum up by saying: The relevant literature remains equivocal, with most studies suggesting benefit from low-carbohydrate eating per se in comparison, generally, to either the typical Western diet or some version of a low-fat diet, with persistent concerns and uncertainty about longer-term effects on health outcomes.

Low-fat/vegetarian diet 
Definition: total daily fat intake below 20% of total calories.

Extensive body of literature exists. The diets of most primates are overwhelmingly plant based and low in total fat and are thought to be reflective of the earliest versions of the native human and prehuman diets, which evolved to include more meat in accord with hunting prowess. Intervention trials have long shown benefits from dietary fat restriction, ranging from weight loss to improvements in various biomarkers to reductions in cardiac events and mortality. Low-fat, plant-based eating has been associated with reductions in cancer and cardiometabolic disease. Uniquely, a very-low-fat diet has been shown to cause regression of coronary atherosclerosis (fat and plaque buildup on the walls of the arteries). High fiber intake in this (or others for that matter) diet might be crucial factor in their positive health effects. That said, there is no decisive evidence that low-fat eating is superior to diets higher in health-full fat in terms of health outcomes over the life span. When food choices are judicious in both contexts, the superiority of fat-restricted versus carbohydrate-restricted eating for weight loss and health is not reliably established.


Low-Glycemic diet
Definition: restricting/excluding foods with high-glycemic index

Clinical trial data are available and generally support efforts to reduce the glycemic load of the diet. Studies focused on this strategy have demonstrated benefits in the areas of weight loss, insulin metabolism, diabetes control, inflammation, and vascular function. Benefits have been seen in studies of both adults and children. Conversely, a high dietary glycemic load has been associated with adverse health effects. A recent meta-analysis concluded that high glycemic load and index are associated with increased risk of cardiovascular disease, especially for women. Most fruits are precluded by a preferential focus on the glycemic index as well. However, evidence that health benefits ensue from jettisoning fruits, or relatively high-glycemic-index vegetables, from the diet does not exist.

Often absent from discussions of low-glycemic diets is the consideration that, as with other dietary categories, there are various means to the same ends. McMillan-Price et al. studied alternative approaches to achieving a reduced glycemic load and demonstrated that a high-fiber, mostly plant-based approach offered metabolic advantages over a high-protein approach.


Mediterranean diet
Definition: based on the traditional dietary pattern that prevails in Mediterranean countries.

It has been associated with increased longevity, preserved cognition, and reduced risk of cardiovascular disease in particular, with some evidence for reduced cancer risk. However, longevity effects of diet, per se, are of course difficult if not impossible to unbundle from the effects of related lifestyle practices and cultural context. Adherence to a Mediterranean diet pattern is potentially associated with defense against neurodegenerative disease and preservation of cognitive function, reduced inflammation and defense against asthma, amelioration of insulin sensitivity, and relatively high scores of objectively measured overall diet quality. Studies have placed a particular emphasis on high intake of vegetables, fruits, nuts, olive oil, and legumes; moderate intake of alcohol; and limited consumption of meat. The contributions of cereal grains and fish are less apparent, perhaps because of lesser effects on health outcomes or less variation available for assessment.


Mixed, Balanced diet
Definition: it belongs to dietary patterns that include both plant and animal foods and conform to authoritative dietary guidelines, e.g. Dietary Recommendations of the World Health Organization

Such diets have figured prominently in the intervention trials of the National Institutes of Health (NIH). The Dietary Approaches to Stop Hypertension (DASH) diet is a salient example. Perhaps because of the ultimate accountability of the NIH to the tax-paying population at large, these federal diets have focused both on enhancements of nutrition and real-world applicability. Even so, efforts to translate the findings of intervention trials to community application have realized limited success. 

The DASH diet, as it has evolved, is a mostly plant-based diet inclusive of some animal products, with an emphasis on low-fat and nonfat dairy products. U.S. News & World Report has deemed DASH the most healthful diet in recent years. This designation, however, derives from the consensus opinion of a panel of expert judges rather than objective data. Data related to a direct comparison of DASH to other reasonable contenders for most healthful diet are lacking. There are some concerns about potential adverse effects of dairy intake that DASH-related literature tends to ignore. The Optimal Macronutrient Intake Trial for Heart Health has demonstrated short-term benefits for overall cardiovascular risk of several variations on the DASH diet theme - intake relatively high in carbohydrate, relatively high in protein, and relatively high in unsaturated fat - and suggested advantages to replacing some carbohydrate with either protein or fat. There are, however, no head-to-head comparisons of a DASH-style diet with other candidate dietary patterns to determine which produces the best long-term health effects.


Paleolithic diet
Definition: diet emulating pattern of our Stone Age ancestors with an emphasis on avoiding processed foods, and the intake of vegetables, fruits, nuts and seeds, eggs, and lean meats. In principle at least, dairy and grains are excluded entirely

Estimates of our Paleolithic dietary intake suggest that we are adapted to a high intake of plant foods and the nutrients they contain; a high intake of dietary fiber; and a fat intake of approximately 25% of total calories. One of the lesser challenges in reaching conclusions about the Paleolithic diet is variation in our ancestral dietary pattern and debate regarding its salient features. If Paleolithic eating is loosely interpreted to mean a diet based mostly on meat, no meaningful interpretation of health effects is possible. 

However even those emphasizing the role of hunting and meat suggest that some 50% of our Stone Age forebears’ calories came from gathered plant foods. Given the energy density of meat relative to most plants, even this translates to a diet that is, by bulk, mostly plants. Although superficially a departure from the other contending diets, a reasonable approximation of a true Paleolithic diet would in fact be relatively low in fat; low in the objectionable carbohydrate sources - namely, starches and added sugars; high in vegetables, fruits, nuts and seeds, and fiber; and low glycemic. An emphasis on lean meat remains distinctive, however, and may represent an advantage related particularly to satiety.


Vegan diet 
Definition: diets excluding all animal products - notably, dairy, eggs, and meats.

As with almost every other dietary approach, vegan eating can be done well or badly. Those committed to long-term veganism are typically well versed in the need to combine plant foods to achieve complete protein and in the role of select nutrient supplements. Those who adopt veganism for a short term, particularly adolescents seeking rapid weight loss, are not as reliably well informed. In general, vegan diets, when well constructed, are associated with health benefits. Intervention trials of short to moderate duration suggest benefits related to overall diet quality, inflammation, cardiac risk measures, cancer risk, anthropometry, and insulin sensitivity.

Intervention trials of vegan diets are limited to those willing to be assigned to such a diet for a span of weeks, months, or years. Given such constraints, data from intervention trials that are related to direct comparison of vegan diets with various other dietary patterns, that are defended from bias, and that examine long-term health effects are essentially nonexistent. This does not argue against vegan diets, but it does argue against overstating the basis for them in evidence related to human health outcomes.

Conclusions:
A common message can be drawn from various studies conducted on various food habits: the case that we should, indeed, eat true food, mostly plants, is all but incontrovertible. Perhaps fortuitously, this same dietary theme offers considerable advantages to other species, the environment around us, and even the ecology within us.

The clutter of competing claims likely obscures the established body of knowledge and forestalls progress, much like the proverbial trees and forest. We need less debate about what diet is good for health, and much more attention directed at how best to move our cultures/societies in the direction of the well-established theme of optimal eating, for we remain mired a long way from it.
-------------------------------------------
Summary ends here.

I hope this post motivates someone to read further and make responsible choices for themself. 

For +ScienceSunday,  curated by +Robby Bowles , +Allison Sekuler , +Rajini Rao , +Chad Haney , +Buddhini Samarasinghe , +Aubrey Francisco , and +Carissa Braun .

#sciencesunday  

Image source: http://crossfitrehoboth.com/
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Hehe, +Chad Haney . 
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Rakesh Yadav

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Some time back Dr. +Noah Diffenbaugh  shared an intriguing  graphic by +Mother Jones  which showed the water usage of few of the California's major crops. Post: http://goo.gl/zUWeJV . The +Mother Jones  articles was about California's dire drought situation, and it tried to put things in perspective about water usage.

I was a little surprised to note that the article didn't even mention the major players of water usage, i.e. livestock industry. Recently +Meiling hope  shared a post which contained a link to a very nice infographic post (http://goo.gl/cqgZRZ) by +WWF Deutschland. The post was about the water usage of a typical Hamburger and it was shared on the occasion of world water day, but it was in German. I thought it might be worth sharing it with wider community so I translated the main parts of the infographic to English. 

Note: 1 Gallon =  3.8 Liters
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I submit that's it's not the meat or the fat that is killing most people, but the bread. So I don't see how substituting more low quality carbs into a person's diet helps nutrition. And I don't mean whole grains vs. highly refined either. All common grains are low quality bulk goods and if you compare food allergies, many more people are allergic to plant based products than are with meat. Ahh, whatever, I was going to talk about sourdough and fermentations but who am i kidding...I'm not going to change anybody's opinion so why bother? <mute>
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Rakesh Yadav

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The extent of NSA's encroachment in our lives is truly amazing! And the fact that these things are already a part of our technological infrastructure makes it even more troublesome.

 If you give even a tiny damn about privacy, then this video will be worth your time.

Via +Joerg Fliege 
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Funny. I feel zero "encroachment". The air knows everything about the
Shape of my body and my lungs, yet I am no worse for that intimate and omnipresent transgression of privacy. Privacy is a manufactured paranoia used by libertarians to promote a fear based agenda.
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Rakesh Yadav

⚔ Advocacy & Activism  - 
 
Looks like this was successful, kudos to Dr. Neal Barnard and Gene Baur.

Debate: Don't Eat Anything With A Face

Pre-debate Poll Results: 24% for | 51% against | 33% undecided

Post-debate Poll Results: 45% for | 43% against | 12% undecided

Haven't watched it yet, I need to wait for it to be freely  available on youtube.
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Gene Baur's position is, don't eat anything with a face, unless it's just a small amount and at that point, then you're just worrying about "personal purity"

If his staff is any indication, sexism is okay as long as it promotes the reductionist mindset

http://ccc.farmsanctuary.org/be-a-better-advocate/read-essays-and-books/

Screw both those ideas
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May be this will finally convince me to buy a smart phone. I am really hoping that this idea works out. 

If you like the concept, then please do spread the word!

#phonebloks  
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Rakesh Yadav

ℹ Resources, Help, & Questions  - 
 
Since sustainability of food is a big concern for many Vegans I am sharing this post here. These numbers might come handy.
 
Some time back Dr. +Noah Diffenbaugh  shared an intriguing  graphic by +Mother Jones  which showed the water usage of few of the California's major crops. Post: http://goo.gl/zUWeJV . The +Mother Jones  articles was about California's dire drought situation, and it tried to put things in perspective about water usage.

I was a little surprised to note that the article didn't even mention the major players of water usage, i.e. livestock industry. Recently +Meiling hope  shared a post which contained a link to a very nice infographic post (http://goo.gl/cqgZRZ) by +WWF Deutschland. The post was about the water usage of a typical Hamburger and it was shared on the occasion of world water day, but it was in German. I thought it might be worth sharing it with wider community so I translated the main parts of the infographic to English. 

Note: 1 Gallon =  3.8 Liters
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+Joab Cohen  assuming that the Mayo contains typical ingredients, i.e. oil and egg, I don't think 60 Liter is too much. 
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Rakesh Yadav

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Do other stars also have spots?

It has been a rather long time since I shared something on G+. Moving and research took its toll.

My recent research endeavours have led me to something really interesting which I would like to share. It is not so often that I get to summarize my research related content without spitting out scientific jargon :)

As you might know Sun is not a uniformly illuminated sphere of light. Every once in a while some strange things appear on the surface of the Sun which are darker and cooler as compared to the rest of the Sun. These darkish regions are called Sun spots.

Sun spots are a complex manifestation of interplay between turbulent plasma motions near the Sun's surface and strong magnetic fields which are generated in Sun's deep interior. Although strong magnetic fields don't give a damn when charged particles flow along them (this is why we get auroras near Earth's poles because magnetic field line are almost vertical and charged particles can enter our atmosphere unhindered ) they really don't like it when charged particles try to go across them. So, when strong magnetic fields pop-up near Sun's surface they interact with the charged plasma and drastically slow down the flow in that region. Since the plasma is not flowing with the same vigour as compared to the other parts of the Sun it can not transfer much heat from the deep interior of Sun. This region with strong magnetic field and suppressed plasma motions, called a Sunspot, acts like a plug which blocks heat from coming out. Less heat means that the gas in this region becomes less hot and shines less brightly. Hence as compared to the rest of the Sun's surface these regions appear darkish. This is why they are called "cool" spot. But don't be fooled, they are cool (at around 3000-4000K)  as compared to the rest of the sun which is at around 6000K.

Another interesting thing about these spots is that if you have a decent telescope you can identify these spots on Sun pretty easily. People have been keeping a record of the appears and disappearance of Sunspot for over two centuries! [EDIT: actually it's more than four centuries, people have been recording it since Galileo's time, including himself]  This observational record of Sunspots is the longest running experiment in human history. Pretty cool. But, hey, aren't we suppose to talk about star-spot? :)

The way through which these spotty features are produced on Sun is rather generic so it will not be surprising if these spots also exist on other stars. And indeed this is the case. Many scientists expect that most of the stars in our universe have these spot on them. But what is the basis of such an expectation. What are the observational evidence we have to support this claim?

There are two ways in which we can infer that a star has spots on it. First one uses a star's light and the other uses the spectral line-profiles. I will talk about the second method later because it is somewhat involved. Lets see how the first method works.

Since stars are very veryyyyy far away we don't have the luxury of resolving their surface. Except for few nearby stars, all stars appear as point-sources of light. Unlike Sun where one can point a detector at southern or northern latitude and record different levels of light a far away star is just a point. A detector records one total value of its light. We can measure a star's light intensity at different times and construct a "light curve". The +NASA  Kepler satellite is nothing but a very sophisticated tool to make such light curves (very very precisely) for thousands of stars.

So we have one light-intensity value which is total sum of light projected towards us by that star. All stars rotate so this intensity value changes if a star has spots on it. Below you see an artificial light-curve (top panel) generated using an artificial star which for some reason has two square-shaped spots on it (yours truly is to blame for this :D). As the spot pass across the visible side of the star the visible intensity changes: it shows a dip when spot is visible. Such kind of variable visible-intensity is shown by most stars to some extent. This gives us a clue that most stars might have spots.
(There are also other stuff going on on stars which can produce variable intensity levels. For the sake of simplicity lets assume only spots are causing them.)

People also step further and try to infer back what kind of spots will produce an observed light-curve. It is like I give you the light curve which I have shown below and ask you to re-produce my rotating star with square-spots. Such an exercise will never give you a proper solution. In the example given below I assumed that I am watching the star such that its rotating poles are perpendicular us, i.e. I am watching it equator on. But unfortunately when we observe stars mostly we don't know the direction of the rotation axis of that star. This now becomes a free parameter in our reverse problem. The reverse problem also suffers one other drawback: spots on a star with one big spot and another star with two or three or more spot can be positioned in such a way that they both produce the same light-curve. Hence this reverse problem of inferring star spots from light-curves inherently produces multiple solution which is not a good thing. We want unique predictions not vague ones which fit everything.

Inferring actual positions and size of star spots from their light-curve is a rather shaky business as you might have gathered. The second method which I mentioned above but didn't explain is much more robust. I will try to summarize that in near future.

Have a starry and spotty night everyone :)

  +ScienceSunday +Rajini Rao  +Robby Bowles  +Allison Sekuler +Buddhini Samarasinghe  +Chad Haney 
#scienceeveryday  
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Done thanks!
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Do other stars also have spots?

It has been a rather long time since I shared something on G+. Moving and research took its toll.

My recent research endeavors have led me to something really interesting which I would like to share. It is not so often that I get to summarize my research related content without spitting out scientific jargon :)

As you might know Sun is not a uniformly illuminated sphere of light. Every once in a while some strange things appear on the surface of the Sun which are darker and cooler as compared to the rest of the Sun. These darkish regions are called Sun spots.

Sun spots are a complex manifestation of interplay between turbulent plasma motions near the Sun's surface and strong magnetic fields which are generated in Sun's deep interior. Although strong magnetic fields don't give a damn when charged particles flow along them (this is why we get auroras near Earth's poles because magnetic field line are almost vertical and charged particles can enter our atmosphere unhindered ) they really don't like it when charged particles try to go across them. So, when strong magnetic fields pop-up near Sun's surface they interact with the charged plasma and drastically slow down the flow in that region. Since the plasma is not flowing with the same vigor as compared to the other parts of theSun it can not transfer much heat from the deep interior of the Sun. This region with strong magnetic field and suppressed plasma motions, called a Sunspot, acts like a plug which blocks heat from coming out. Less heat means that the gas in this region becomes less hot and shines less brightly. Hence as compared to the rest of the Sun's surface these regions appear darkish. This is why they are called "cool" spots. But don't be fooled, they are cool (at around 3000-4000K)  as compared to the rest of the sun which is at around 6000K.

Another interesting thing about these spots is that if you have a decent telescope you can identify these spots on Sun pretty easily. People have been keeping a record of the appears and disappearance of Sunspot for over two centuries! [EDIT: actually it's more than four centuries, people have been recording it since Galileo's time, including himself]  This observational record of Sunspots is the longest running experiment in human history. Pretty cool. But, hey, aren't we suppose to talk about star-spots? :)

The way through which these spotty features are produced on Sun is rather generic so it will not be surprising if these spots also exist on other stars. Many scientists expect that most of the stars in our universe have these spot on them. But what is the basis of such an expectation? What are the observational evidence we have to support this claim?

There are two ways in which we can infer that a star has spots on it. First one uses a star's light and the other uses the spectral line-profiles. I will talk about the second method later because it is somewhat involved. Lets see how the first method works.

Since stars are very veryyyyy far away we don't have the luxury of resolving their surface. Except for few nearby stars, all stars appear as point-sources of light. Unlike Sun where one can point a detector at southern or northern latitude and record different levels of light a far away star is just a point. A detector records one total value of its light. We can measure a star's light intensity at different times and construct a "light curve". The +NASA  Kepler satellite is nothing but a very sophisticated tool to make such light curves (very very precisely) for thousands of stars.

So we have one light-intensity value which is total sum of light projected towards us by that star. All stars rotate so this intensity value changes if a star has spots on it. Below you see an artificial light-curve (top panel) generated using an artificial star which for some reason has two square-shaped spots on it (yours truly is to blame for this :D). As the spot pass across the visible side of the star the visible intensity changes: it shows a dip when spot is visible. Such kind of variable visible-intensity is shown by most stars to some extent. This gives us a clue that most stars might have spots.
(There are also other stuff going on on stars which can produce variable intensity levels. For the sake of simplicity lets assume only spots are causing them.)

People also step further and try to infer back what kind of spots will produce an observed light-curve. It is like I give you the light curve which I have shown below and ask you to re-produce my rotating star with square-spots. Such an exercise will never give you a proper solution. In the example given below I assumed that I am watching the star such that its rotating poles are perpendicular us, i.e. I am watching it equator on. But unfortunately when we observe stars mostly we don't know the direction of the rotation axis of that star. This now becomes a free parameter in our reverse problem. The reverse problem also suffers one other drawback: spots on a star with one big spot and another star with two or three or more spots can be positioned in such a way that they both produce the same light-curve. Hence this reverse problem of inferring star spots from light-curves inherently produces multiple solutions which is not a good thing. We want unique predictions not vague ones which fit everything.

Inferring actual positions and size of star spots from their light-curve is a rather shaky business as you might have gathered. The second method which I mentioned above but didn't explain is much more robust. I will try to summarize that in near future.

Have a starry and spotty night everyone :)

  +ScienceSunday +Rajini Rao  +Robby Bowles  +Allison Sekuler +Buddhini Samarasinghe  +Chad Haney 
#scienceeveryday  
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+Julian Gold , hmm....I see...Thanks for your indulgence. I need to keep this in mind while I am interpreting my simulation results in future.
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Rakesh Yadav

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This is indeed an amazing invention!

Via +Supriyo Paul 

Image courtesy: http://abstrusegoose.com/strips/the_greatest_inventor.png
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And amazingly, it's smaller on the inside!
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Rakesh Yadav

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Cosmic rays and cloud formation

Some time back I summarized a paper discussing a possibility of changes in Earth's magnetic field via changes in surface coverage of ice on Earth during ice-age cycles (http://goo.gl/XCYz0l). The researchers commented that such changes in Earth's magnetic field, although rather small, can potentially affect Earth's climate by modulating the extent of Cosmic rays reaching Earth's lower atmosphere layers. Stronger magnetic field can deflect more Cosmic rays away from Earth. New evidence (discussed below) propose that such an effect is minute and insignificant.

In layman terms, cloud are formed when the concentration of water in air is so high that the air becomes saturated and excess water begins to condensate on some suspended particles in air. These suspended particles could be dust or big enough clusters of some molecule. Air nearly devoid of suspended particles will not be suitable for cloud formations as water needs something to condensate on. Interestingly, suspended particles are necessary but not sufficient for cloud formation. We still don't completely understand what are the sufficient conditions for cloud formation. As you know clouds are very important for our climate since being white they significantly affect the amount of solar energy reaching Earth's surface. 

Lack of proper understanding of cloud formation physics is responsible for one of the most significant uncertainty in climate models (IPCC). It is of utmost importance to figure out what affects, or better yet, what control the formation of clouds.

A recent paper published in Nature (http://dx.doi.org/10.1038/nature12663 Open access!) presents very interesting results which shed some light on the cloud formation puzzle.  Researchers used the CLOUD (Cosmics Leaving OUtdoor Droplets) facility at CERN to study the interaction of lab produced Cosmic rays with artificial "atmospheres". 

[Paraphrasing paper's text where necessary]

Sulphuric acid (H2SO4) is thought to be the most potent supplier of suspended particles responsible for producing clouds. The atmospheric concentration of H2SO4 is about 0.04–1.2 parts per trillion by volume. But the amount of clouds produced via this mechanism is rather small and does not explain the observed cloud coverage. Many of the tiny drops formed via H2SO4 particles and water interaction are unstable and disappear pretty fast by evaporation. We need a mechanism to stabilize these droplets.*

Ammonia and Cosmic rays (because of its ion producing abilities) were thought to be our go-to guys which could help to stabilize the first tiny H2SO4 + H2O drops. But again, even after Ammonia and Cosmic rays's help the suspended particles produced were too few. New results from this CLOUD experiment suggest that Amines (basic organic compounds containing a nitrogen atom) are a much more potent stabilizer and even a few handful of these molecules per trillion by volume can increase the number of stable H2SO4 particles by around a factor of 1000! Researchers were also able to use quantum chemistry simulations to provide a viable mechanism for this behavior. Such increased production of stable H2SO4 particles, and hence more water droplets, can explain the observed cloud formation rate to a good extent. 

The amount of Cosmic rays reaching the earth didn't seem to matter much as the effect produced by Amines is so big.

This study provides a possible answer to one puzzle, and, as with most scientific studies, raises even more questions. The minute quantities of Amines in atmosphere affecting the amount of particles in atmosphere by a factor of thousand makes their modelling even more difficult since we do not precisely know the Amine's concentration in Earth's atmosphere. Humans are the main emitter of such compounds followed by natural decay of organic compound in ocean. Even a small uncertainty in Amine concentration can produce dramatic effects which might be un-physical. This cosmic ray and cloud formation puzzle seems to getting even more complex!

Well, don't be so sad, it's progress nonetheless. Lets see what the future brings. 

#sciencesunday   +ScienceSunday 
+Rajini Rao  +Buddhini Samarasinghe  +Allison Sekuler  +Robby Bowles 

Attched image depicts interaction of Cosmic rays particle with Earth's atmosphere. Image source: NASA
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  • Indian Institute of technology, Kanpur, India
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Hey there fellow Earthling!...I am a PhD student and I study how magnetic fields are generated in planets and stars.

Few key-words which describe my interests when I am not unraveling deep secrets of nature are (no hierarchy): Environmental conservation, sustainable living, computers in research, philosophy, history of science.
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  • Georg-August University of Göttingen
    Computational Astrophysics, 2012 - present
  • Max-Planck institute for solar system research, Katlenburg-Lindau
    Computational Astrophysics, 2012 - present
  • Indian Institute of Technology Kanpur
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This is a protest in response to your support of climate change deniers!
Public - 7 months ago
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Almost all dishes were vegan and awesome (main reason for visiting). I had lunch and I tried the buffet costing 175 SEK, a little pricey but it was very filling. I actually had so much that I am thinking of skipping the dinner :D... The view of the whole Stockholm city was really nice. The environment was cozy with friendly staff. Don't forget to try the vegan sweet dishes!
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