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[redshift-13]

206 responses to this question

Much more at the link.

[space-davidjanes-blog]

Progress In Rocketry

At the close of the year 2015, in close succession, two rockets left the ground, crossed the Karman line (at 100 km altitude) into space, and return intact under their own power to a soft landing on the surface of the earth. In the space business, new rockets are launched at regular intervals, but the now-imminent launch of a used rocket is important news.

[empiricaldaily]

As the most scientifically significant moment of 2015, a 28-author team publishes in Lancet about the results of a Phase II clinical trial of an Ebola vaccine. Nearly 8,000 Guinean subjects, careful experimental design, 100 percent effectiveness at preventing disease occurrence when administered immediately after exposure to someone with Ebola. Yes, this isn’t the end of the disease, and the research started long before the West African epidemic. But this is a rough approximation of scientists, with lightning speed, saving us. It would be nice if the general public thought the same.

Robert Sapolsky. 2016. (Title: edge.org annual 2016 question: what do you consider the most interesting recent [scientific] news? What makes it important?) 

[empiricaldaily]

Think for a moment about a termite colony or an ant colony—amazingly competent in many ways, we can do all sorts of things, treat the whole entity as a sort of cognitive agent and it accomplishes all sorts of quite impressive behavior. But if I ask you, "What is it like to be a termite colony?" most people would say, "It's not like anything." Well, now let's look at a brain, let's look at a human brain—100 billion neurons, roughly speaking, and each one of them is dumber than a termite and they're all sort of semi-independent. If you stop and think about it, they're all direct descendants of free-swimming unicellular organisms that fended for themselves for a billion years on their own. There's a lot of competence, a lot of can-do in their background, in their ancestry. Now they're trapped in the skull and they may well have agendas of their own; they have competences of their own, no two are alike. Now the question is, how is a brain inside a head any more integrated, any more capable of there being something that it's like to be that than a termite colony? What can we do with our brains that the termite colony couldn't do or maybe that many animals couldn't do?

Daniel Dennett. 2013. (Title: HeadCon '13: WHAT'S NEW IN SOCIAL SCIENCE? (Part X) Daniel C. Dennett: The De-Darwinizing of Cultural Change)

[empiricaldaily]

With the dark matter question, which I am a little more actively involved at this moment because there is a brand new dataset that is just incredible, much of the mapping of dark matter that I do is to try and understand how granular dark matter is, in terms of how it's spatially distributed in the universe. We know, for example, that dark matter is lightly smeared everywhere in the universe, but that there are regions where it is lumped and accumulated due to gravity. These regions that have copious amounts of dark matter reveal themselves to us because of the light bending that they cause, gravitational lensing of background galaxies that lie behind them. This phenomenon was predicted by Einstein, according to which when you have a distant galaxy and it is viewed through a screen of a massive lump of dark matter, light rays from these distant glowing galaxies get deflected and what you end up seeing is a distorted shape rather than the true shape of the background galaxy. Sometimes you have a huge lump of dark matter. Both dark matter and visible matter will bend light, but it's just that dark matter is the dominant matter component, and it's implicated in much of the light bending that we see. Sometimes there is so much dark matter concentrated that you split a single light beam into multiple beams, so you end up seeing multiple copies of the same, single background galaxy. In fact, you have only one true object that's emitting light, but you end up seeing multiple copies of it all distorted and misshapen.

Priyamvada Natarajan. 2015. (Title: The Exquisite Role of Dark Matter)

[empiricaldaily]

By classifying proteins as interactors, we can clearly identify the specific DNA fragments that qualify as replicators. Now, one property that replicators must possess is a consistent phenotypic effect on their interactors, as Dawkins elegantly showed in The Extended Phenotype. Strikingly, genes do not have this crucial property. Through the amazing set of posttranscriptional mRNA processing mechanisms uncovered in the last 40 years (including alternative splicing and RNA editing), transcription of a single gene often results in the production of many distinct protein isoforms with very different functional roles. DNA fragments coding for individual protein domains, however, do have a consistent phenotypic effect, since protein domains are functionally independent parts of proteins that play the same role no matter which isoform they appear in. So proteins are an example of what we are calling the fundamental interactors, the interactors that experience the consistent phenotypic effects of corresponding replicators. Notice that it then becomes straightforward to picture how the phenotypic features of the fundamental interactors came about, in glorious molecular detail: small variations in the sequence of domain-coding fragments that allow protein domains to perform their function particularly well are selected for over thousands of generations, enhancing cooperation and expanding the range of cooperative opportunities available between fundamental interactors and ultimately contributing to the fitness of the organism. Of course, domain-coding fragments are not the only replicators in eukaryotes; the differential selection for regulatory elements and transposons is just as important for understanding how the features of organisms came to be. This extra layer in the hierarchy of interactors helps show how a molecular developmental toolbox can mix and match gear to assemble organisms, and potentially fills the gap that the evo-devo crowd has been saying was slighted by the gene's-eye view, integrating the beautiful details of molecular biology with Dawkins' vision of life.

Daniel Dennett, Patrick Forber, Nikolai Renedo. 2015. (Title: A Vision of Life, in Molecular Detail [edge.org])

[t-e-l-e-p-a-t-h-y]

It is possible that we are rare, fleeting specks of awareness in an unfeeling cosmic desert, the only witnesses to its wonder. It is also possible that we are living in a universal sea of sentience, surrounded by ecstasy and strife that is open to our influence. Sensible beings that we are, both should worry us.

Timo Hannay, when asked by EDGE.org What *Should* We Be Worried About?

[empiricaldaily]

We would like to propose a friendly amendment that will allow for more accurate identification of these two entities, the replicator and the vehicle. The vehicle concept is slightly too restrictive, but in both directions: By adopting David Hull's term interactor, we can identify not only the extended phenotypes, but phenotypes that are cohesive entities smaller than the individual organism, sets of phenotypic products that interact with their molecular environment to cause the differential selection of replicators. Individual proteins, for instance, interact with other protein interactors in the cellular environment, cooperating with each other to build functional cells and organisms. The success of the replicators that build proteins does not depend on whether the protein survives to reproduce, as in the case with vehicles, but rather on how well the proteins cooperate with the surrounding proteins to build an organism with a fitness advantage.

Daniel Dennett, Patrick Forber, Nikolai Renedo. 2015. (Title: A Vision of Life, in Molecular Detail [edge.org])