There’s some bad news, followed by good news, but partially countered by further bad news. The bad news is that our population is growing, and therefore our food requirements, and yet we are approaching the limits of our ability to increase crop yield with cultivation alone. Experts can quibble about whether or not we are at or near the limit, but it’s pretty clear that we are not going to double crop efficiency in the next 50 years through cultivation.

That, however, is pretty much what we need to do if we are going to meet humanity’s caloric needs. By 2050 yields will need to be 60% higher than 2005, and needs will likely continue to rise before they stabilize. Sure, there are some gains to be made in reducing waste, but not nearly enough. And sure, we need to take steps to stabilize our population more quickly, like fighting poverty and promoting the rights of women in developing countries.

But even under optimistic conditions – we simply need to grow more food. Further, as I recently reviewed, we are pretty much using all the good arable land available. Expanding into more land for growing food is not a good option.

So really we have one viable option if we are going to meet our food needs – genetically modifying crops. That is the good news – GMOs actually have the potential to significantly increase crop yields. One way to do that is through making photosynthesis more efficient. It turns out, there are several ways to do this.

First, there is a difference between C3 and C4 photosynthetic pathways. The C4 pathway is more efficient, and increases biomass production. Part of the efficiency is through better carbon concentration mechanisms. This pathway has independently evolved in many plants, and there are others that are part way between C3 and C4, but our major food crops all use C3.

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It’s pretty clear at this point that we need to be moving away from fossil fuels as quickly as possible. Fossil fuels essentially are stores of ancient carbon, long sequestered from the environment, that we are now releasing back into the environment, altering the balance of the carbon cycle leading to increased forcing of global temperatures.

The good news is that other forms of energy are advancing nicely. Wind and solar are now past the point of cost effectiveness in many situations – without even counting the cost of pollution, which I think should be counted. If you consider the health and environmental effects of fossil fuel pollution, all other forms of energy become much more cost effective. (This is the idea behind the carbon tax.)

Nuclear, it seems, is likely going to have to be part of any future energy infrastructure that uses minimal fossil fuel, but lags in cost effectiveness. The nuclear industry is responding, however, with safer and cheaper designs.

It is heartening to know that we essentially have the technology to phase out fossil fuel right now, if we had the political will to do so. It is, of course, disheartening that we lack the political will even in the face of a solid scientific consensus, and clear technology options. Further, whatever technology we choose to invest in will only get better over time.

This constant progress has made the conversation about renewable energies in particular interesting – because the facts on the ground are constant evolving. Solar and wind keep getting better and more cost effective. Wind power is particularly interesting because there are so many factors involved – in both the design of the turbines themselves and their placement.

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Have you ever been in a semi-familiar location but couldn’t quite place where you were, then suddenly the landmarks line up and you know where you are? This might happen when entering a familiar location from an unusual direction, for example. Also (a seemingly unrelated question), when you visualize abstract ideas, do you arrange them physically. For example, do you visualize time (like days, weeks, months, years), and if so is there a particular physical relationship by which you mentally organize the progress of time?

Scientists from the Max Planck Institute for Human Cognitive and Brain Sciences (MPI CBS) and the Kavli Institute for Systems Neuroscience in Trondheim, Norway have published a paper in which they propose these two mental phenomena are directly related. One of the scientists, Edvard I. Moser, won the 2014 Nobel Prize for some of this work.

For background, researchers discovered that there are a type of neuron called place cells in the hippocampus (specifically area CA1) that store the memory for specific locations. When you are in a familiar location, a unique pattern of place cells will light up. Further, there is a second type of cell called grid neurons, which are arranged in a hexagonal pattern in the nearby entorhinal cortex. These grid cells light up in sequence as you move through your physical space – the physical arrangement of the grid neurons map to the physical arrangement of your environment.

This is an elegant system – your brain basically has a movable grid map, the grid keeps track of your local navigation, while the place cells keep track of where the map is.

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We are heading into cold and flu season, so Time magazine decided to helpfully tell us what the science says about echinacea and the common cold. Unfortunately, they completely bungled their report, getting the bottom line wrong. Exactly where they go wrong, however, is extremely common and instructive.

The terrible article is partly not the fault of the author. They spoke to experts and tried to do a balanced piece. Unfortunately, there are experts out there who are biased and just wrong. The author was not able to make sense of the evidence themselves, and so they helplessly just passed along whatever nonsense they were told. This is another manifestation of the infiltration of “alternative” medicine into our system – there are always going to be “experts” out there who are just alternative cranks, but they will get quoted along side more serious scientists.

For example, they write:

Other experts say there is evidence that echinacea can be helpful. “Echinacea is popular because it does work for at least some people,” says Kelly Kindscher, a professor of environmental studies at the University of Kansas who has written a textbook on echinacea. While some clinical trials have not shown echinacea to be effective, Kindscher says others have found benefits.

I understand listening to someone who wrote a textbook on the topic, but this conclusion flies in the face of published reviews. The next statement shows where they go wrong:

A 2010 study published in the Annals of Internal Medicine compared echinacea to a placebo and to no treatment at all. It found evidence that echinacea outperformed both when it came to reducing the duration of the common cold — but these benefits were too small to be considered statistically significant.

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Material science is, in my opinion, one of the most underappreciated of the sciences. Perhaps because it is so wonky, it doesn’t seem to get much public attention, and yet the development of new materials arguably has the potential to change our civilization more than any other single advance. Our level of technology is largely defined by the materials we have mastered, and discovering a new material is literally a technological game changer.

It’s always hard to predict the next big advance, but there are some intriguing candidates. Interest seems to be clustering around anything on the nano scale – such as carbon nanofibers. Two-dimensional materials that are only one or a few atoms thick (which includes carbon nanofibers) is an area of intense research as well. There is also a relatively new class of materials called metamaterials, which do interesting things with light and other forms of electromagnetic radiation. Metamaterials essentially have emergent properties, and could have potentially exotic applications such as rendering objects invisible in certain frequencies.

A new paper attempts to codify and name one particular type of metamaterial that the authors (Justin C. W. Song & Nathaniel M. Gabor)  are proposing be called “electron quantum metamaterials.”

These types of materials are comprised of two or more layers of two-dimensional nanomaterial that are rotated with respect to each other so that special patterns emerge. This is likened to a moire pattern, where two sets of thin parallel lines are offset from each other by a certain amount and that creates an interference pattern. The interference patterns emerges from the specific relationship between the lines.

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One year ago, in October 2017, astronomers detected the first confirmed interstellar visitor to our solar system – an asteroid dubbed Oumuamua. The name is Hawaiian for “scout”, as if the asteroid is a messenger from a distant system. A Hawaiian name was chose because the object was discovered by the Panoramic Survey Telescope and Rapid Response System-1 (Pan-STARRS-1) in Hawaii. Determining that Oumuamua was an interstellar object was not difficult – the determination was based on its trajectory. It was traveling really fast, too fast for any object originating from our own system. It’s velocity would also take it out of our system – it was moving too fast to be captured by the gravity of our sun.

All of that is cool enough, but astronomers carefully analysing the trajectory of Oumuamua discovered (and published their findings in June 2018) that its acceleration could not be explained entirely by gravity. Some force was pushing, ever-so-slightly, on the object. This acceleration could be explained by outgassing, if there were any volatiles on Oumuamua that were heating up as it got closer to the sun. These gases would be like tiny rocket engines. Observations of the object did not detect any comet-like tail, which is why it was thought to be an asteroid. But if this new observation were correct, then it would have the ices and gases associated with a comet.

Oumuamua was discovered 40 days after its closest approach to the sun, when it was already on its way out of our solar system. At this point it should have been slowing down a bit from the pull of the sun’s gravity, but instead it was speeding up slightly. This could be explained by outgassing caused by heat from the sun.

This led to a debate about whether or not Oumuamua was an asteroid with a small amount of ice, or a comet that had lost most of its ice. It seems that the object exists in the gray zone between asteroid and comet (and we run into yet another definition demarcation problem). Further, close analysis showed that Oumuamua is very elongated (often described as “cigar-shaped”) and quickly tumbling end-over-end.

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In May I reported on the preliminary report of an extensive study of cancer incidence in mice and rats exposed to radio-frequencies. Yesterday the researchers released the final report, with essentially the same conclusions. This is prompting another round of the media reporting that a study links cell phone use to cancer – but the data does not show that, and what it does show is still not impressive.

To summarize the results, and the points I made in my previous review of this study – there were actually two studies, one in mice and one in rats. The researchers exposed some of the animals to intermittent (10 minutes on, 10 minutes off) radio frequencies in varying strengths, whole body, from the womb until death. They found a statistically significant increase in some types of brain and heart tumor in male rats only exposed to the radio frequencies, but not in female rats, and not in male or female mice.

Right there, this is a strange result. Why only male rats? If this effect does not even extend to female rats, or to mice, why should we suspect it extends to humans? Further, whenever study results are quirky like this, in my opinion that calls into question the relevance, and even the reality, of the claimed effect. It smacks of random noise.

Another red flag is the large number of comparisons being made in the study. For example, the researchers looked for a particular type of tumor, schwannoma, in various tissues. They found a statistically significant increase in the heart, but not in other tissues, and not when you look at all schwannomas – only when you consider the heart separately. This looks suspicious for not controlling for multiple comparisons. You have to make a statistical adjustment for doing so, and I see no mention that they did.

Further, the absolute numbers are fairly low, with affected rats all being in the single digits. This makes subtle confounding effects and also random quirky effects more likely.

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Is putting your toddler in front of an educational video harmful or helpful? This is an important question for many parents, especially in homes where both parents work and taking care of young children can be hectic. Putting a child in front of a video is the closest things parents have to an off switch for their kids, so it can be very tempting to rely upon the distraction of an iPad or TV to keep their attention while you make dinner or attend to some other task.

There is also a cottage industry of videos marketed to parents with very young children. Some are clearly nothing more than an entertaining distraction, like videos of other children playing with toys (which are incredibly popular). But parents can also be sold on the idea that their children are learning while being distracted, thereby alleviating any guilt from relying on the video-nanny.

There has therefore been increasing research into the effectiveness of video learning for very young children (and older children and adults, but we’ll focus on young children for now).  Here is a recent study of this topic which includes a great overview of prior research.

Previous research has mostly shown that young children do not respond to video the same way they respond to a live person. Exposing toddlers to their native language or a foreign language through a video or just audio seems to have no benefit, compared to the identical content presented through a live person. The probable reason for this is that we are programmed from birth to be extremely social, and young children typically will pay great attention to other people – more than anything else. A video of a person, unfortunately, just doesn’t cut it.

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A new report looking at vaccine confidence in the EU shows some troubling trends. Belief in the safety and effectiveness of vaccines seems to be very regional. We see this in the US as well as Europe. In this survey they found:

The results of the survey suggest that a number of member states – including France, Greece, Italy, and Slovenia – have become more confident in the safety of vaccines since 2015; while Czech Republic, Finland, Poland, and Sweden have become less confident over the same period.

In some countries anti-vaxxers have a stronger foothold, and are actually decreasing acceptance of vaccines. But there are two other trends that are more disturbing. First, in the countries with decreasing vaccine acceptance there is high levels of vaccine skepticism among general practitioners.

While GPs generally hold higher levels of vaccine confidence than the public, the survey found that 36% of GPs surveyed in Czech Republic and 25% in Slovakia do not agree that the MMR vaccine is safe and 29% and 19% (respectively) do not believe it is important.

Those are shockingly high numbers for physicians. This is one of my greatest fears about the advance of alternative medicine and anti-scientific medical views – that they will affect the medical profession itself. Once unscientific ideas creep into the culture of medicine, the game is all but lost. This is why teaching pseudoscience in medical school is such an alarming problem. In this survey, the countries with higher levels of GP vaccine skepticism, had higher levels of public skepticism and lower levels of vaccine compliance.

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I am what is known as a mild protan. That means that the cones of my retina that perceive red and green wavelengths are not as separated in their frequency response as they should be. This overlap causes some shades of red and green to look similar. As far as I am aware, the only deficit this has caused in my life is the inability to see some of those numbers in the circles of colored dots used to test color vision. Although some color combinations, such as the orange and green of the Miami Dolphins jerseys, are uncomfortable to look at.

But other people have more severe forms of color blindness that can actually affect their lives, such as the ability to distinguish red and green traffic lights.

I was therefore intrigued on a personal as well as scientific level when I first heard the claims for glasses that can compensate for some forms of color blindness. To me the claims sounded only semiplausible. The problem with partial color-blindness is in the cones – the retinal cells that perceive color – so how could you correct this by simply filtering the frequency of light? But I left open the possibility that by specifically altering some colors you could enhance their separation, making them easier to distinguish.

I never had the opportunity to test the glasses (they are expensive) but fortunately there is now an independent study of their effectiveness. Specifically researchers at the University of Granada tested the EnChroma® glasses.  As the researchers note, the company that makes the EnChroma glasses has been watering down their claims in the typical way that supplement manufacturers often do, which for me is a huge red flag. They now state on their website:

“EnChroma glasses are an optical assistive device for enhancement of color discrimination in persons with color blindness; they are not a cure for color blindness. Results vary depending on the type and extent of color vision deficiency per individual.”

Sounds an awful lot like the “structure function” claims of supplements, which cannot claim to treat or cure any disease. I could not find more specific claims made by the manufacturer on their website. They also say things like:

“EnChroma color blindness glasses can have a profound impact on how people see their world.”

Yeah – so do sunglasses. This is a clever implied claim here, without actually making a specific claim. They also present reviews on their site, quoting other people who make more profound claims. This is the common “testimonials” approach – let other people make the claims so you don’t have to.

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