The standard, near-universal type of photosynthesis uses the green pigment, chlorophyll-a, both to collect light and use its energy to make useful biochemicals and oxygen. The way chlorophyll-a absorbs light means only the energy from red light can be used for photosynthesis.
Since chlorophyll-a is present in all plants, algae and cyanobacteria that we know of, it was considered that the energy of red light set the ‘red limit’ for photosynthesis; that is, the minimum amount of energy needed to do the demanding chemistry that produces oxygen. The red limit is used in astrobiology to judge whether complex life could have evolved on planets in other solar systems.
However, when some cyanobacteria are grown under near-infrared light, the standard chlorophyll-a-containing systems shut down and different systems containing a different kind of chlorophyll, chlorophyll-f, takes over.
Cross-section of beach rock (Heron Island, Australia) showing chlorophyll-f containing cyanobacteria (green band) growing deep into the rock, several millimetres below the surface
Until now, it was thought that chlorophyll-f just harvested the light. The new research shows that instead chlorophyll-f plays the key role in photosynthesis under shaded conditions, using lower-energy infrared light to do the complex chemistry. This is photosynthesis ‘beyond the red limit’.
Lead researcher Professor Bill Rutherford, from the Department of Life Sciences at Imperial, said: “The new form of photosynthesis made us rethink what we thought was possible. It also changes how we understand the key events at the heart of standard photosynthesis. This is textbook changing stuff.”
In the mass-media era, the general public primarily experiences classical music through detached snippets of larger pieces extracted to lend their symbolic power to a commercial agenda. Artists and advertisers dissect classical works into short melodies — quotable passages severed from their original context — assembling a menu of musical leitmotifs to bolster their message with a desired tone, mood, or association. Like artificial flavoring for the ear, these symphonic excerpts infuse scenes with the synthetic emotion of choice. Need a touch of European elegance? Mozart will make that minivan commercial suddenly suave. Concerned a slow sequence leaves your audience snoozing? Wake them up with the “William Tell Overture” for instant adrenaline. Does your pancake promo lack punch? Reroute Wagner’s “Ride of the Valkyries” from Valhalla to the International House of Pancakes.
The artistic consequences of such practices are devastating. Conscripting Wagner’s Valkyries as pancake saleswomen necessarily lowers their impact at the opera house. Some pieces are quoted so often that their secondary associations overtake and cheapen the original music.Carmina Buranaexists as a permanent musical cliché. Orff’s “O Fortuna” evokes only kitsch; under which circumstances can a listener now have an authentic encounter with that choral-chanting calamity?
Such a sound-bite culture negates the definitive value of classical composition: the extended development of complex musical themes. Extended musical forms allow the listener to appreciate the subtle interplay of motif and movement — and it is exactly this nuanced appreciation that quote-clipping nullifies. There is a two-part mechanism to extract and transplant a tune: detach a 15-second theme from a 45-minute symphony (where it functioned as an integrated part in an organic whole) and attach it to an alien subject. Uproot “O Fortuna” from a Latin cantata, so it can be grafted onto a Domino’s Super Bowl spot. These transplants produce jarring mashups that trigger another insidious side effect: by always quoting works out of the context the public forgets that they have a context. The spectator forgets that “O Fortuna” could be glorious in its original context because it’s absurd hyping Domino’s Pizza. In sum, in the remix media ecosystem, famous compositions degenerate from serious music into decorative sound, applied like wallpaper to lay a poignant surface over banal intentions.
No big surprise, but oh well. Would have been cool. Neat test setup, though!
It was bound to happen eventually. A group of researchers that may actually be competent and well-funded is investigatingalternative thrust concepts. This includes our favorite, theWTF-thrusterEM-drive,as well as something called a Mach-Effect thruster. The results, presented atSpace Propulsion 2018, are pretty much as expected: a big fat meh.
What even is privacy, what does a right to privacy mean, and rest on?
Possibly the discussion is using the wrong vocabulary. “Privacy” is an odd name for the good that is being threatened by commercial exploitation and state surveillance. Privacy implies “It’s nobody’s business,” and that is not really what Roe v. Wade is about, or what the E.U. regulations are about, or even what Katz and Carpenter are about. The real issue is the one that Pollak and Martin, in their suit against the District of Columbia in the Muzak case, said it was: liberty. This means the freedom to choose what to do with your body, or who can see your personal information, or who can monitor your movements and record your calls—who gets to surveil your life and on what grounds.
A core idea that Donald J. Trump has embraced throughout his time in public life has been that the United States is losing in trade with the rest of the world, and that persistent trade deficits are evidence of this fact.
In this accounting, the $69 billion United States trade deficit with Mexico or $336 billion gap with China is something of a scorecard reflecting diminishing American greatness.
The vast majority of economists view it differently. In this mainstream view, trade deficits are not inherently good or bad. They can be either, depending on circumstances.
As the president’s emphasis on trade deficits puts the United States at odds with allies — in this case at the Group of 7 leaders meeting this weekend in Canada — the trade-offs in making this an overwhelming focus of economic diplomacy are becoming more clear.
Many physicists argue that Einstein’s position is implied by the two pillars of modern physics: Einstein’s masterpiece, the general theory of relativity, and the Standard Model of particle physics. The laws that underlie these theories are time-symmetric — that is, the physics they describe is the same, regardless of whether the variable called “time” increases or decreases. Moreover, they say nothing at all about the point we call “now” — a special moment (or so it appears) for us, but seemingly undefined when we talk about the universe at large. The resulting timeless cosmos is sometimes called a “block universe” — a static block of space-time in which any flow of time, or passage through it, must presumably be a mental construct or other illusion.
Many physicists have made peace with the idea of a block universe, arguing that the task of the physicist is to describe how the universe appears from the point of view of individual observers. To understand the distinction between past, present and future, you have to “plunge into this block universe and ask: ‘How is an observer perceiving time?’” saidAndreas Albrecht, a physicist at the University of California, Davis, and one of the founders of the theory ofcosmic inflation.
Others vehemently disagree, arguing that the task of physics is to explain not just how time appears to pass, but why. For them, the universe is not static. The passage of time is physical. “I’m sick and tired of this block universe,” saidAvshalom Elitzur, a physicist and philosopher formerly of Bar-Ilan University. “I don’t think that next Thursday has the same footing as this Thursday. The future does not exist. It does not! Ontologically, it’s not there.”
Last month, about 60 physicists, along with a handful of philosophers and researchers from other branches of science, gathered at thePerimeter Institute for Theoretical Physicsin Waterloo, Canada, to debate this question at theTime in Cosmologyconference. The conference was co-organized by the physicistLee Smolin, an outspoken critic of the block-universe idea (amongother topics). His position is spelled out for a lay audience inTime Rebornand in a more technical work,The Singular Universe and the Reality of Time, co-authored with the philosopherRoberto Mangabeira Unger, who was also a co-organizer of the conference. In the latter work, mirroring Elitzur’s sentiments about the future’s lack of concreteness, Smolin wrote: “The future is not now real and there can be no definite facts of the matter about the future.” What is real is “the process by which future events are generated out of present events,” he said at the conference.
With hunting being so costly to the velvet worm, it comes as little surprise that some species choose to not go hunting alone. One Australian species- Euperipatoides rowelli- has been shown to form packs, with social hierarchy, pack protection, and team hunting. These packs have an ‘alpha female’, which usually is selected by being the largest and most aggressive individual in a group.
The velvet worms form a clump, and the largest female makes her way to the top, biting and pushing the others as she does. In this way, the velvet worms not only form a tolerance to being close to one another, but also an understanding of who is – both literally and figuratively – at the top of the pack.
The pack hunts together, trapping larger prey through using multiple slime jets. The alpha female will then, much like a male lion in a pack, push the other members aside to have their feed, after which the others will join in on the feast.
I’m so in love with the species of the Cambrian Explosion lately…
All of the animals here are products of the Cambrian Explosion. This event was a boom of life that occurred somewhat earlier during this era and gave rise to some of the strangest creatures that have ever lived. Most of them belonged to families doomed to die out while others managed to pull through. First of all, nothing at this time had a backbone. For many millions of years, invertebrates would be the dominant form of life on the planet and nowhere is it more obvious than here in the Burgess Shale.
