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The standard DNA 'prism' is a gel electrophoresis column, that is, a long tube filled with jelly through which an electric current is passed. A solution containing the scissored stretches of DNA, all jumbled together, is poured into one end of the tube. The DNA fragments are all electrically attracted to the negative…
And Mallow laughed joyously, "You've missed, Sutt, missed as badly as the Commdor himself. You've missed everything, and understood nothing. Look, man, the Empire can replace nothing. The Empire has always been a realm of colossal resources. They've calculated everything in planets, in stellar systems, in whole…
‘The achievement of the Kaminari-zoku implies that there are other spacetimes. Certainly other regions of the Universe beyond our causal horizon. If rational actors have evolved in them, they will have broken their Planck locks – or worse, evolved natively in an environment with no restrictions on computational…
When life spreads out and diversifies in the universe, adapting itself to a spectrum of environments far wider than any one planet can encompass, the human species will one day find itself faced with the most momentous choice that we have had to make since the days when our ancestors came down from the trees in Africa…
The scientific worker is brought up with the moral values of his neighbours. He is perhaps fortunate if he does not realize that it is his destiny to turn good into evil. An alteration in the scale of human power will render actions bad which were formerly good. Our increased knowledge of hygiene has transformed…
The basic idea of Astrochicken is that the spacecraft will be small and quick. I do not believe that a fruitful future for space science lies along the path we are now following, with space missions growing larger and larger and fewer and fewer and slower and slower as the decades go by. I propose a radical step in…
The numerical results of my calculations show that the quantities of energy required for permanent survival and communication are surprisingly modest. For a society with the same complexity as the present human society on Earth, starting from the present time and continuing forever, the total reserve of energy…
"These remarkable creatures combine the characteristics of animals and plants and so I call them animal-plants. ..." "All right. Don't get angry. Just explain how your creatures avoid getting dried up like mummies." "That is simple. Their skin is covered with a glassy layer, thin and flexible but absolutely…
Piet Hut, another Dutch astronomer fifty years younger than Jan Oort, decided to take seriously the possibility that comet showers are periodic. If they are periodic, the theory that they are caused by the random passing-by of alien stars cannot be right. If showers are periodic, they must be explained by a different…
In the year 1900 Max Planck wrote down an equation, E = hv, where E is the energy of a light wave, v is its frequency, and h is a constant which we now call Planck's constant. Planck's equation was the beginning of quantum theory. It said that energy and {22} frequency are the same thing measured in different units…
"We have a phenomenon very like that in industry," Galiagante said when she was done. "It's called green thumb syndrome. It sometimes occurs when a new plant establishes a complicated but known procedure for the first time. Your people set it up perfectly but nothing happens. The oxides won't reduce, the catalysts…
In programmable matter, the same cubic meter of machinery can become a wind tunnel at one moment, a polymer soup at the next; it can model a sea of fermions [elementary particles], a genetic pool, or an epidemiology experiment at the flick of a console key. Ten times as large a simulation will simply require ten cubic…
In metric, one millilier of water occupies one cubic centimeter, weighs one gram, and requires one calorie of energy to ehat up by one degree centigrade--which is 1 percent of the difference between its freezing point and its boiling point. An amount of hydrogen weighing the same amount has exactly one mole of atoms…
“Christmas, Kwanza, whatever you call it — I fucking hate it. But winter… that’s different. I love winter. Here’s why. My grandparents dreaded winter. Back when they were kids, winter always meant bad things. Meant another war. Meant foodlines, and power outages, and people their age dying alone in the cold. But when…
Our Sun is significantly enriched, having formed when the Universe was more than 9 billion years old in the plane of a spiral galaxy, one of the most enriched places in the Universe. Yet, when our Sun formed, it was still made out of — by mass — 71% hydrogen, 27% helium, and about 2% “other” stuff. If we convert that…
Mix up a batch of 50/50 water and glue, dissolve a spoonful of Borax in more water, then mix the whole mess together. (If you want real numbers, mix 1/4 c water with 1/4 glue & dissolve 1 tsp Borax in 1/8 c water, but really, you can be pretty slapdash about this.) As you knead it, the slime will quickly start…
So, myth one is that humans are evolved to eat meat and that Palaeolithic peoples consumed large quantities of meat. Humans have no known anatomical, physiological, or genetic adaptations to meat consumption. Quite the opposite, we have many adaptations to plant consumption. Take, for example, vitamin C. Carnivores…
The very first time you learned about carbon dioxide was probably in grade school: We breathe in oxygen and breathe out carbon dioxide. Any eight-year-old can rattle off this fact. More specifically, the mitochondria within our cells perform cellular respiration: they burn carbohydrates (in the example shown below…
In a way it is even humiliating to watch . . . miners working. It raises in you a momentary doubt about your own status as an 'intellectual' and a superior person generally. For it is brought home to you, at least while you are watching, that it is only because miners sweat their guts out that superior persons can…
Twinkle, twinkle little star. I don't wonder what you are, For by spectroscopic ken I know that you are hydrogen.