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Comment: Re:How are they rocky? (Score 1) 50

by reverseengineer (#48919285) Attached to: Kepler Discovers Solar System's Ancient 'Twin'

What's interesting about this star though, is that according to the paper, Kepler-444 is not some primordial supergiant, but a K dwarf (orange, of the same type as Alpha Centauri) with a smaller companion red dwarf (or possibly two companion red dwarf stars which are closely bound to each other).

Comment: Re:Mass production ? (Score 3, Informative) 187

by reverseengineer (#48607089) Attached to: Graphene: Fast, Strong, Cheap, and Impossible To Use

Mass production- of graphene powder. Cambridge Nanosystems' process makes flakes of graphene in the 200-800 nm diameter range; cf. this interview with their chief scientist. It's still a valuable material with many potential uses; that interview talks about composite materials and conductive inks. However, it's a very different product with different applications from a large-scale monolayer sheet.

Comment: May not be a practical drug. (Score 4, Informative) 153

by reverseengineer (#48578907) Attached to: "Fat-Burning Pill" Inches Closer To Reality

The original paper for this was discussed yesterday on In The Pipeline. The point was raised that the mechanism involved, the JAK-STAT signalling pathway is used quite broadly throughout the body in the control of cell growth and differentiation. There are several Janus Kinase (that's JAK) inhibitors already on the market or in development, and they are powerful immunosuppressants indicated for the treatment of things like rheumatoid arthritis or leukemia. They tend to be the sorts of drugs whose advertisements say stuff like, "Xeljanz may increase your risk of serious infection." Notably, Xeljanz (tofacitinib) popped up in the news a few months ago when it was used to grow hair in a patient with alopecia universalis (who was already taking the drug for an autoimmune disease) and the headlines exclaimed that a cure for baldness was on the horizon. Now, a single drug that burns fat, grows hair, and relieves psorasis sounds like a miracle, but the reality is that's a sign that these compounds act more broadly than is desirable.

As the paper's authors themselves put it:

The utility of JAK inhibition as a therapeutic strategy for obesity is complicated by the well-described role of this signalling pathway in the immune system. In fact, tofacitinib is approved in the United States to treat rheumatoid arthritis. Thus, if one were to imagine targeting adipose tissue by in vivo administration of an IFN–JAK–STAT inhibitor or similar compound it would almost certainly need to be delivered locally and prevented from spreading systemically or alternatively targeted selectively to white adipocytes. One could also conceive of a cell-based therapy wherein JAK inhibition of patient-derived adipocytes ex vivo is followed by transplantation to treat obesity, but this therapeutic modality would need to overcome numerous and significant obstacles before becoming a reality.

Comment: Re:Toxic light (Score 3, Informative) 34

by reverseengineer (#48224113) Attached to: Recent Nobel Prize Winner Revolutionizes Microscopy Again

The toxicity is actually an indirect effect. The fluorescent dyes can in their excited states react with molecular oxygen to produce reactive oxygen species that damage tissues. By reducing the time and energy of excitation of the fluorophores (by only exciting those actually about to be scanned by the microscope), this technique reduces the amount of toxic byproducts.

Comment: Re:More details (Score 2) 294

Most artificial sweeteners sold in powder form contain a simple sugar or starch to add bulk and give the product free-flowing granules more similar to sugar. Since saccharin, sucralose, and aspartame all taste hundreds of times sweeter than sugar, they are used in much lower amounts, with bulk added for the consumer-serving preparations so that you don't have to add micrograms of sweetener to your coffee to get the equivalent sweetness of sugar. Either glucose (usually listed as dextrose) or maltodextrin are generally used, which is interesting since it means that sugar substitutes generally contain a small amount of carbohydrates. The little single-serving packets tend to have about 3 (kilo)calories each; in the US, the FDA allows foods with less than 5 calories to be labeled as "zero calorie," so they generally are.

I note that this study did happen to use all powder-form sweeteners (dissolved in water) which means that there would some small amount carbohydrate in the solution. That's a perfectly reasonable way to run this study, since these are widely used preparations of these sweeteners, but I do wonder if there might be a difference with a genuinely digestible-carbohydrate-free preparation.

Comment: Re:Would YOU be able to sleep in space?? (Score 3, Interesting) 106

by reverseengineer (#47635137) Attached to: Study Finds That Astronauts Are Severely Sleep Deprived

I read the Apollo 11 Lunar Surface Journal during the anniversary back on July 20th, and one of the entries that stood out to me was a section called "Trying to Rest," which detailed a time between the end of the astronauts' moonwalk, but prior to when they needed to make preparations to liftoff from the Moon. A period of about 7 hours was scheduled for the astronauts to sleep, but

[Armstrong - "(The quality of the rest) was poor in my case."]

[Aldrin - "I'd say the same thing."]

In their technical debrief, Armstrong and Aldrin detailed some problems with their sleep environment- too cold, too bright, too noisy, but yeah, that they were also just too excited to sleep. (It does mention that most of the technical problems were worked out by Apollo 15, and the last few crews got decent sleep on the lunar surface. I'm still convinced that if it were me, I would have responded to planned rest periods with "HOUSTON, I CAN SLEEP WHEN I GET BACK FROM THE MOON, OVER.")

Comment: Re:Federation of Am... Soc.. for Exper... Biology? (Score 1) 63

by reverseengineer (#47555447) Attached to: UK Team Claims Breakthrough In Universal Cancer Test

Ah, I didn't think to look at the other societies. They do apparently have a large campus at that address, so I guess they probably have real office space for those societies there. The property was a country estate when they bought it- now it's inside the Beltway.

Comment: Re:Federation of Am... Soc.. for Exper... Biology? (Score 1) 63

by reverseengineer (#47555291) Attached to: UK Team Claims Breakthrough In Universal Cancer Test

27, according to their website. They do cover a wide range of disciplines at least. I was going to note that the Genetics Society of America and the American Society of Human Genetics seem like they'd have a lot of overlap, but then I noticed that they're headquartered at the same address, so I imagine they came to a similar conclusion at some point.

Comment: Re:size? (Score 4, Informative) 94

by reverseengineer (#46468849) Attached to: Monster Hypergiant Star Discovered

The 22 and 40 look like lower and upper bounds. In section 6.1 of the paper, it says, "we infer the lowest current mass of the system to be 22±5 [solar masses]" . They mention this value comes from a calculation based on Kepler's 3rd law. So it looks like the lower bound comes from orbital mechanics based on the orbit of the companion star and the upper bound of 40 comes from their interferometry observations and modeling of that data, but they consider it more likely that the true value is closer to the higher value.

Comment: Re:Whine (Score 1) 412

I get the sense that the Daily Doubles have historically been located in the high dollar values of a category because it has been more traditional behavior for contestants to start at the top of the board and work their way down. That way, the Daily Doubles tend to get exposed later in the round, when contestants generally have more money to wager and the game situation is more likely to be swung by a big win or loss. As I understand it, the DD wager may still be made for up to the highest dollar amount on the board for the round even if the player's current score is less than that amount, but it still is undesirable from an audience point of view for the only DD of the first round to be "wasted" on the first question.

Of course, from what you might call a "power player" perspective, the Daily Double spaces are very valuable, both in terms of the potential money you can earn and in terms of denying your opponents that potential. It's smart to try and find them as soon as possible. Making the DD spaces truly random on the board may limit the use of the "harder levels first" strategy, but there's still value in building an early lead (this is assuming that as a "power player," the hard questions on Jeopardy aren't going to be substantially harder for you than the easy ones) and maintaining control of the board, so I don't think it would totally go away.

Comment: Re:"A molecule nearly identical" (Score 1) 131

by reverseengineer (#45914069) Attached to: Metal-Free 'Rhubarb' Battery Could Store Renewable Grid Energy

I don't know why the focus is on rhubarb specifically. Anthraquinones are found all throughout nature, usually as some sort of red or yellow pigment (like the pigment carmine, for instance, made from cochineal insects). Rhubarb contains some compounds call anthraquinone glycosides, but I wouldn't characterize them as being "nearly identical" to anthraquinone disulfonic acid on account of sugar molecules not being very similar to sulfonic acid groups.

Comment: Re:Cafestol and Kahweol (Score 3, Informative) 49

It's something that's been known for awhile- there are papers on it going back to the early 1980s, though I'd imagine it may not have been heavily publicized at first due to the American preference at the time for paper-filtered drip coffee. Methods that retain more of the oils or the grounds themselves in the finished coffee, like boiled coffee or French press tend to have much higher concentrations.

This paper and this paper have some more information.

The way to make a small fortune in the commodities market is to start with a large fortune.