Wikipedia:Reference desk/Archives/Science/2013 October 27

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October 27

About (vomitting while) pregnant

Is there vomiting after 2 months of pregnant and why? — Preceding unsigned comment added by Titunsam (talk • contribs) 09:58, 27 October 2013 (UTC)

See Morning sickness for our article on the subject. Tevildo (talk) 10:04, 27 October 2013 (UTC)

This may not be the reason though. If you or someone you know is unwell, please seek the advice of a medical professional. 80.254.147.164 (talk) 09:33, 28 October 2013 (UTC)

Insolation as a function of latitude (alone)

Hi! I am looking for a function for the average insolation a a particular latitude gets over a year. Essentially, it's the information in the upper map of the first image in the insolation article, except, well, there's no indication what formula they used to obtain that result. Now, as far as I understand, it should be a matter of integrating the formula for day-averaged insolation, which is given as

${\overline {Q}}^{\text{day}}={\frac {S_{o}}{\pi }}{\frac {R_{o}^{2}}{R_{E}^{2}}}\left[h_{o}\sin(\phi )\sin(\delta )+\cos(\phi )\cos(\delta )\sin(h_{o})\right]$,

with $\sin \delta =\sin \varepsilon ~\sin(\theta -\varpi )\,$, for θ = 0 to 360°, except that for one thing I'm afraid it exceeds my mathematical abilities, and anyway the formula includes a parameter h₀ for which they give no value (and no way to calculate it). Could you help me out? Thanks :) JaneStillman (talk) 21:13, 27 October 2013 (UTC)

Woolly bear caterpillars

When I was little, my parents told me never to touch caterpillars, so I'd never touched one until a few minutes ago. It's warm outdoors today, and I'm sitting in a chair on the porch; the woolly bear crawled up the chair, up my shirt, and onto my neck — quite surprising, and I had no clue what it was until I'd shaken it off. Two questions arise from this:

1. How do they move? Little feet like centipedes or millipedes, or suction feet like ants, or something else entirely? And how do they climb human skin, since it's so different from everything that they normally climb?
2. Do these caterpillars actively go looking for food, or do they just wander randomly until they happen upon some? I'm left wondering if it thought that I was a food-bearing plant or if it just found me and decided to climb and see what happened.

Nyttend (talk) 21:15, 27 October 2013 (UTC)

Ants have suction-cup feet ? StuRat (talk) 21:28, 27 October 2013 (UTC)

Pyrrharctia isabella, doing an amazing imitation of a pipe cleaner.

• Our article on caterpillar covers their general leg anatomy, which is the same for the whole order Lepidoptera. At this time of year they are looking for places to overwinter, and not for food. μηδείς (talk) 21:30, 27 October 2013 (UTC)

Ants and caterpillars both have feet with little hooks on them. Ants have legs, but caterpillars have prolegs. Ant feet look like this [1]. Different types of caterpillars have more variety in their feet, some look like this [2], some look like this [3]. The latter foot may look cup-like, but I don't think any suction per se is involved. Anyway, their feet work just fine on plants, rocks, curtains, siding, and human skin. At the small scale, there is plenty of roughness of little feet to get a grip.

Medeis is right that they are looking to overwinter, but that doesn't mean they aren't also eating...

As for how they forage, that can depend on what kind of "wooly bear" you mean. E.g. Garden_tiger_moth has a fairly general diet, so "find vertical surface and ascend" is a decent strategy, especially considering they were hatched from eggs deposited by flying adults (who probably found an area with a good food source). They probably do also use smell a bit. If you are interested how caterpillars in general find food, I can probably get some decent refs for that. SemanticMantis (talk) 21:48, 27 October 2013 (UTC)

I'd just add, if not handled gently, the hairs do detach and irritate. μηδείς (talk) 22:02, 27 October 2013 (UTC)

What kind of woolly bear — I have no clue. Between colorblindness and no knowledge of entymology, I really know nothing of caterpillars and am unable to describe the ones in question. Since they're so furry and since I've never touched one before, I've never seen feet and didn't know that all caterpillars would have the same general leg anatomy. I admit that I was surprised what it felt like, and somewhat nervous after so doing: my parents always told me that their hairs were irritants, and that's why I've never touched them. Nyttend (talk) 22:10, 27 October 2013 (UTC)

There are several "dangerous" caterpillars including the Hickory Tussock Caterpillar that have Urticating hairs. Rmhermen (talk) 03:11, 28 October 2013 (UTC)

Fukushima radiation on the NW coast of the US

Friends of mine keep sending me alarming articles about how high levels of radiation either have already, or are about to, engulf Oregon, Washington and California from a plume of radiation from Japan. I'm skeptical, but when I looked into the issue I was unable to find published research from anyone actually measuring, or using science to predict, the degree of exposure. There are a lot of statements either reassuring people or whipping up alarm, but little based on actual monitoring. I'm sure I'm looking in the wrong place - but could someone link me to some hard science on the increased dose someone living on the pnw coast is likely to have already, and in the next few years, get? Thanks! — Preceding unsigned comment added by 71.214.113.234 (talk) 23:49, 27 October 2013 (UTC)

The United States Department of Energy is the federal agency that implements policy, and conducts and administers the hard science related to atomic energy and safety. From their website, here is a starter article: ‘’Radiation Monitoring Data for the Fukushima area, (2011), which is a pointer in the right direction. I'll see if I can find any more elaborate reports specifically publishing data and summary results for the Pacific coast of the United States. Nimur (talk) 00:00, 28 October 2013 (UTC)

Thanks - that looks like the Japan data, which is a start - I'm really looking for data on the US PNW coast - really appreciate your help! — Preceding unsigned comment added by 71.214.113.234 (talk) 00:09, 28 October 2013 (UTC)

In fact, a special website was set up on behalf of the President's directive (during the immediate aftermath of the incident) for rhe DOE and NNSA to fully inform the American public and document all data: http://energy.gov/japan2011 - a website most recently updated in January of 2013. After a cursory review of the data, even in the days immediately following the incident, radiation levels measured at several locations in Japan (including Fukushima) were below a level that would ever cause harm, (loosely speaking, at a level below "background radiation" levels, as measured in rem). So it would appear that the hard data contraindicates any significant long-term health hazards resulting from the nuclear incident. That is not to say the incident had no effect - in fact, this review from the DOE's permanent monitoring station at Amchitka indicates a measured biological effect, as published in April 2013: Biological monotoring at Amchitka appears to show impacts from the Fukushima Dai-ichi incident. So, we can summarize that the effects on humans (in Japan, Alaska, and the Pacific coast of the United States) should be "very small," but in deference to scientific observations and careful data analysis, we should qualify that the effects are non-zero. Nimur (talk) 00:15, 28 October 2013 (UTC)

And in case you haven't already found the link, the May 2012 issue of Health Physics was entirely devoted to the Fukushima incident, including nine articles from prominent government scientists in the Department of Energy, and the National Nuclear Security Agency, as well as articles from other points of view, and an editorial called "The States' Perspective" outlining how state governments (including Washington and Oregon) dealt with the public demand for information, and the difficulty of providing factual scientific answers in the hours and days immediately following the incident. In the phrasing of the journal editor, the radiation was "orders of magnitude" below a concerning level - but in the rush to inform the public, some states published data provided by the federal government - the Environmental Protection Agency - which may have led to unnecessary alarm because it was presented without context.

The Fukushima reactor incident has been widely studied from many many points of view - from the view of physicists, biologists, and climatologists; from the view of first responders and nuclear safety and security agencies; from the view of policy makers and governments in the United States, Japan. and elsewhere. There's no shortage of published opinions on the incident. I'm sure we can help you find more information if you seek it. Nimur (talk) 00:40, 28 October 2013 (UTC)

For the enthusiast historians: here's EPA's corollary, http://www.epa.gov/japan2011/ - also archived for posterity. You will note that EPA's March 11 statement has been redacted, even in the historical archive, and the oldest press release is dated March 15, 2011. Nimur (talk) 00:58, 28 October 2013 (UTC)

Thanks - I still have not been able to track down any recent measurement data for the Pacific Northwest Coast - there's plenty of opinion, not many numbers that I can find. Really appreciate the help! — Preceding unsigned comment added by 71.38.131.41 (talk) 01:58, 28 October 2013 (UTC)

The more I look into this the more I think there may not actually be anyone monitoring radiation levels arriving in the PNW - at least not publishing if they are. Anyone found anything different? Thanks! — Preceding unsigned comment added by 71.214.118.54 (talk) 13:59, 28 October 2013 (UTC)

That is not accurate. Every nuclear power station in the United States is continuously monitoring radiation levels inside and outside the facility. You can locate every single facility and check the data for that location. Many laboratories and special sites, like the Hanford Facility in Washington, perform extensive monitoring for various radioactivity and other nuclear activity. A few select sites - like the Amchitka Island station in the Aleutians - perform even more rigorous monitoring. The U.S. Environmental Protection Agency, in conjunction with the USDA, EPA, and FDA, tests food products and milk for nuclear contamination on a constant basis. So far, very little of interest has been found with any relation to the 2011 Japan incident, which is why there aren't very many recent press-statements. Everything that was scientifically valid has probably long faded below the noise floor.

But the problem is, radioactivity is not as simple as some other properties, like "temperature." We can link you to climatology data, where you can view hourly archives of every temperature at every weather station in the USA for the last fifty years. But radiation is not a single parameter; there are many natural and man-made sources, and there are several types of harmful and non-harmful nuclear decay activity and othher radioactivity. For example, if you read the article about Amchitka, you'll see the problems they faced: they have to measure radioactivity level and further normalize by the isotope ratios between Cesium-137 and Cesium-134. The absolute radiation levels are so low that they are unmeasurable with, say, a geiger counter; you need a complete laboratory analysis to tease these details out.

So, if you have a specific request - say, historical data on calcium isotope ratios in milk produced in the Pacific North West, we can find that data for you. (Here's an FDA press-release from early September, on data collected about milk, just a few days before our Government shut down last month; the next data release may be delayed). Or if you want total electron count in Earth's ionosphere as measured by radiosonde, we can find that data for you - here's data for right now, from NOAA'S Space Weather Prediction Center. The data is there, and it's available. But, the consensus by scientists is, those data show no signficant cause-and-effect relationship with the Fukushima Dai-Ichi incident in 2011. So, you'll probably not see a lot of current scientific summary articles putting these pieces together and showing no effect - especially since that work has already been very thoroughly completed in 2011 and 2012. Academic journals do not like to publish statements of fact that confirm the status quo or the null hypothesis. Nimur (talk) 15:48, 28 October 2013 (UTC)

Thanks - I appreciate the thorough response - I'm still left with no real solid data or analysis to show wether or not there is any effect of the ongoing Japan leak on the PNW coast, which is a little frustrating... — Preceding unsigned comment added by 71.214.118.54 (talk) 20:40, 28 October 2013 (UTC)

How to See RadNet Air Monitoring Data, from the EPA... "EPA's nationwide radiation monitoring system, RadNet, consists of two components. First, stationary and deployable air monitors measure radiation 24 hours a day, 7 days a week. The map below provides monitoring results as graphs that are updated several times daily. You can also search the RadNet database in EPA's Central Data Exchange (CDX) to find monitoring data. Second, EPA samples precipitation, drinking water, and milk on a routine schedule and tests them for radiation in a laboratory. The latest RadNet sampling results are available in Envirofacts." I don't know how this type of data could be made any more solid, or the analysis presented in any more straightforward way, unless it explicitly summarized the measurements in response to the Fukushima incident . Nimur (talk) 00:42, 29 October 2013 (UTC)

Hey that's great - that's exactly the kind of thing I was looking for - thanks for pointing me in EXACTLY the right direction! — Preceding unsigned comment added by 71.214.118.54 (talk) 01:56, 29 October 2013 (UTC)

I think that you have the answers you need, but you might find these articles from Snopes.com useful: Fukushima Emergency, Nuclear Fallout map and Giant Killer Hornets. I'll bet that the articles your friends send you are somewhat like those quoted by Snopes, or at least use the same (unreliable or misrepresented) sources. Sjö (talk) 10:25, 29 October 2013 (UTC)