Wikipedia:Reference desk/Archives/Science/2012 June 24

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June 24[edit]

yoga asanas as therapy for herniated disc[edit]

I am a yoga teacher - trained in the Iyengar method. I have a client who wants help with debilitating back pain and stress due to a herniated disc. Guidance would be welcome. Pippa — Preceding unsigned comment added by 41.221.159.83 (talk) 11:27, 24 June 2012 (UTC)[reply]

Ummm...we're not supposed to give medical advice. I've never seen someone ask the RD for medical advice so they can treat a paying customer though. That is a new one. 101.173.170.147 (talk) 11:49, 24 June 2012 (UTC)[reply]
(after ec) We don't give medical advice here. However, I suggest you ask a physiotherapist as some of their exercises are based on yoga asanas. --TammyMoet (talk) 11:50, 24 June 2012 (UTC)[reply]
For those not as familiar with it as the OP, Wikipedia has an article about Iyengar Yoga. There is also an article about Spinal disc herniation and I echo strongly the urging above to seek advice from a qualified doctor, both because a proper assessment is done with imaging equipment such as MRI and because there are a number of treatments, among which spinal manipulation is controversial or contraindicated. DriveByWire (talk) 13:45, 24 June 2012 (UTC)[reply]

Papaver somniferum[edit]

Are these Papaver somniferum? 88.173.200.107 (talk) 14:46, 24 June 2012 (UTC)[reply]

Without seeing the leaves or flowers, I don't think you can say more than that they are Papaver. Lots of poppies have fruit (or whatever you call it) that looks like that. Looie496 (talk) 15:37, 24 June 2012 (UTC)[reply]
Based on OR I am about 80% certain they are papaver somniferum. The pale bluish glaucous leaves are visible at the bottom of the photo. Richard Avery (talk) 17:56, 24 June 2012 (UTC)[reply]

Trying to make equivalent colors match equivalent return rates[edit]

I want to alter the color scheme in this triangular spreadsheet graph so that it matches the color scale on this New York Times chart. Any ideas? 71.212.226.91 (talk) 18:21, 24 June 2012 (UTC)[reply]

Display the chart on screen. Press ctrl-PrtSc. Open PAINT program. Press ctrl-V to paste the screen image. Click Save as... Give a filename with Save as type GIF (*gif). Use a hex editor such as HEXPLORER to look into the .gif file and find the palette; its location is described in the article Graphics Interchange Format. Locate the bytes for colours you want to change and change them. Save your edited .gif file. DriveByWire (talk) 18:44, 24 June 2012 (UTC)[reply]
If you want to do it exactly, you'll have to do something like that. If you just want to get the general appearance, then what you need to know is that the two color scales differ in saturation. Whether you can alter the color scale in Google Spreadsheet to achieve that is more than I know. Looie496 (talk) 19:06, 24 June 2012 (UTC)[reply]

100-year floods[edit]

100-year flood includes the following statement:

There are a number of assumptions which are made to complete the analysis which determines the 100-year flood. First, the extreme events observed in each year, must be independent from year-to-year. In other words the maximum river flow rate from 1984, can not be found to be significantly correlated with the observed flow rate in 1985. 1985 can not be correlated with 1986, and so forth.

Let's say that a massive flood happens in a place on 31 December, and it's not subsided by midnight; it ends up being a 100-year floor and is the highest water level for both years. How do the statistical assumptions account for such a situation, since the massive flood of 31 December and the massive flood of 1 January are obviously related? Nyttend (talk) 21:14, 24 June 2012 (UTC)[reply]

Because 100 year flood zones determine flood insurance rates, property values (and thereby property tax) they are subject to political manipulation. They currently mean something like "a flood that would only be expected once every 100 years, if extreme weather was what it was like in 1980." 71.212.226.91 (talk) 21:24, 24 June 2012 (UTC)[reply]
that's an interesting assumption... how could the maximum river flow from one year to the next NOT be significantly correlated? Makes my hackles rise.Gzuckier (talk) 06:11, 25 June 2012 (UTC)[reply]
Correlation has a very specific meaning here. It's possible for the maximum flow to be uncorrelated (eg. if the the flow rate depends entirely on how many hurricanes cross the river's drainage basin in a given year), or highly correlated (eg. a series of high-flow years straighten and scour the river's path, reducing the maximum depth, while a series of low-flow years cause meanders and sandbars to form, slowing the water and making floods deeper). --Carnildo (talk) 02:33, 26 June 2012 (UTC)[reply]

Gz, when there is a "100 year flood" in one of the two years! This is a case of statistics lying. Obviously they would just include that event in either one year or the other like "jerrymandering." So it would keep the integrity of the significant event intact and only if another event occurred earlier in the previous year would they likely count that event for that year. That is the point of the 100 year flood to find outliers of the data not to mask the outliers with statistics.165.212.189.187 (talk) 18:02, 25 June 2012 (UTC)[reply]

Nyttend, also if a flood spans the end of one year and continues into the next, it is still just one flood. Different organizations use different criteria as to determining the date for the flood, but they are not listed in both years. Some may date the flood from the moment the waterway passes designated flood stage, while others may date it at the crest or high-water mark.    → Michael J    00:09, 27 June 2012 (UTC)[reply]
Note that a flood on Dec 31-Jan 1 is quite unlikely in the Northern temperate zone, as most floods occur during snow melt in the spring, or heavy rains in the summer, or hurricanes of the fall. However, I agree that it's not a correct assumption that floods in one year are independent of the next:
1) Global warming obviously affects all years, so increases the risk of floods steadily, in certain places.
2) Weather patterns like El Nino have an effect on several years in a row. StuRat (talk) 00:19, 27 June 2012 (UTC)[reply]
stu, what are you trying to say?68.83.98.40 (talk) 04:49, 27 June 2012 (UTC)[reply]
That either the op's example is bad as it relates to the actual problem of correlation or that all years are correlated by default so no matter how different floods might be from year to year it would still be considered normal flooding?165.212.189.187 (talk) 14:25, 27 June 2012 (UTC)[reply]