Category: Science
Matt Ridley’s Thesis: When Ideas Have Sex
At TEDGlobal 2010, author Matt Ridley shows how, throughout history, the engine of human progress has been the meeting and mating of ideas to make new ideas. It's not important how clever individuals are, he says; what really matters is how smart the collective brain is.
The Educated Man
Global classical solutions of the Boltzmann equation with long-range interactions
The T-shirt from USC’s School of Information Theory
A lovely bit of satire on Evolution vs. Creationism… what will they come up with next?
Constitutional debate continues over whether public schools should include biblical Armageddon alongside global warming in end-of-world curriculum. http://v.theonion.com/onionstudios/video/1368/640.mp4
A New Low in Quantum Mechanics
He really has a great sense of humor, doesn’t he?
Stem cell treatment goes from lab to operating room | CNN.com
Imagine having your back cut open, part of your spine removed, a stabilizing device that resembles a mini oil rig mounted on your back, the outer membrane of your spinal cord sliced open and experimental stem cells injected into it -- all for the advancement of science because it's not expected to benefit you.
First U.S. stem cells transplanted into spinal cord | CNN.com
For the first time in the United States, stem cells have been directly injected into the spinal cord of a patient, researchers announced Thursday.
Degradable quantum channels are among the only channels whose quantum and private classical capacities are known. As such, determining the structure of these channels is a pressing open question in quantum information theory. We give a comprehensive review of what is currently known about the structure of degradable quantum channels, including a number of new results as well as alternate proofs of some known results. In the case of qubits, we provide a complete characterization of all degradable channels with two dimensional output, give a new proof that a qubit channel with two Kraus operators is either degradable or anti-degradable, and present a complete description of anti-degradable unital qubit channels with a new proof. For higher output dimensions we explore the relationship between the output and environment dimensions (dB and dE, respectively) of degradable channels. For several broad classes of channels we show that they can be modeled with an environment that is “small” in the sense of ΦC. Such channels include all those with qubit or qutrit output, those that map some pure state to an output with full rank, and all those which can be represented using simultaneously diagonal Kraus operators, even in a non-orthogonal basis. Perhaps surprisingly, we also present examples of degradable channels with “large” environments, in the sense that the minimal dimension dE>dB. Indeed, one can have dE>14d2B. These examples can also be used to give a negative answer to the question of whether additivity of the coherent information is helpful for establishing additivity for the Holevo capacity of a pair of channels. In the case of channels with diagonal Kraus operators, we describe the subclasses that are complements of entanglement breaking channels. We also obtain a number of results for channels in the convex hull of conjugations with generalized Pauli matrices. However, a number of open questions remain about these channels and the more general case of random unitary channels.
Microscopy, phenotyping and visual screens are frequently applied to model organisms in combination with genetics. Although widely used, these techniques for multicellular organisms have mostly remained manual and low-throughput. Here we report the complete automation of sample handling, high-resolution microscopy, phenotyping and sorting of Caenorhabditis elegans. The engineered microfluidic system, coupled with customized software, has enabled high-throughput, high-resolution microscopy and sorting with no human intervention and may be combined with any microscopy setup. The microchip is capable of robust local temperature control, self-regulated sample-loading and automatic sample-positioning, while the integrated software performs imaging and classification of worms based on morphological and intensity features. We demonstrate the ability to perform sensitive and quantitative screens based on cellular and subcellular phenotypes with over 95% accuracy per round and a rate of several hundred worms per hour. Screening time can be reduced by orders of magnitude; moreover, screening is completely automated.
Related: https://www.news.gatech.edu/2008/06/23/automated-microfluidic-device-reduces-time-screen-small-organisms
Previously reported better fertilization rate after intracytoplasmic single sperm injection (ICSI) than after subzonal insemination of several spermatozoa was confirmed in a controlled comparison of the two procedures in 11 patients. Intracytoplasmic sperm injection was carried out in 150 consecutive treatment cycles of 150 infertile couples, who had failed to have fertilized oocytes after standard in-vitro fertilization (IVF) procedures or who were not accepted for IVF because not enough motile spermatozoa were present in the ejaculate. A single spermatozoon was injected into the ooplasm of 1409 metaphase II oocytes. Only 117 oocytes (8.3%) were damaged by the procedure and 830 oocytes (64.2% of the successfully injected oocytes) had two distinct pronuclei the morning after the injection procedure. The fertilization rate was not influenced by semen characteristics. After 24 h of further in-vitro culture, 71.2% of these oocytes developed into embryos, which were transferred or cryopreserved. Only 15 patients did not have embryos replaced. Three-quarters of the transfers were triple-embryo transfers. High pregnancy rates were noticed since 67 pregnancies were achieved, of which 53 were clinical, i.e. a total and clinical pregnancy rate of 44.7% and 35.3% per started cycle and 49.6% and 39.2% per embryo transfer. A total of 237 supernumerary embryos were cryopreserved in 71 treatment cycles.
Originally published in 1969. This book explains what is wrong with the traditional methodology of “inductive” reasoning and shows that the alternative scheme of reasoning associated with Whewell, Pierce and Popper can give the scientist a useful insight into the way he thinks.
References:
- History of the Inductive Sciences by William Whewell (1837)
- Introduction à l’étude de la médecine expérimentale by Claude Bernard (Paris, 1865)
- Karl Popper
- Karl Pearson (math)
Brief Review: Santiago Ramón y Cajal’s “Advice for a Young Investigator”
Biography & Autobiography
MIT Press
2004
book (paperback)
150
Library
This recently rediscovered classic, first published in 1897, is an anecdotal guide for the perplexed new scientific investigator as well as a refreshing resource for the old pro.
This is certainly worth the read for the high qualities of its translation and vocabulary. There are lots of great aphorisms and brilliant bits of advice. Some of the parts about patriotism and information about things like picking a wife are anachronistically funny to read 100+ years after they were written.