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What Different Blood Types Mean? Anonymous 19/01/23(Wed)22:32 No. 16741 ID: 175ba2 [Reply]
16741

File 154827913693.jpg - (296.22KB , 900x633 , transfusion-history-1.jpg )

The first experiments with human blood donation happened in the early 19th century. Did they even know what blood types were back then? Wait, what are they?
You can read more here: https://bit.ly/2DtOqs7




Anonymous 19/01/23(Wed)12:33 No. 16739 ID: 739a37 [Reply]
16739

File 154824322756.jpg - (11.70KB , 480x360 , hqdefault.jpg )

Science failed to convince several people in my life that the Earth was round

I find it an inferior path in life

Explain


>>
Anonymous 19/01/23(Wed)19:52 No. 16740 ID: be6f8f

You find what to be an inferior path? Science or being a flat-earther?

No flat Earth theory is capable of explaining all phenomena that we observe:
1. On a flat Earth there would be no horizon. There would be nothing stopping you from looking at Europe from the coast of North America, provided you were high up enough and had a potent enough telescope. Ships just past the edge of the horizon would not appear to sink. Telecomminications over long distances would be much easier; the whole point of satellites is that you can use them to transmit radio signals of (more or less) any frequency over the horizon. Radio over the horizon is possible, by bouncing the signal over the top layers of the atmosphere, but it requires specific frequencies, and specific conditions that aren't always available.
2. No flat Earth theory has ever put forth a serious description of celestial mechanics for the Solar System. Even something as simple as the distance between the Earth and the Sun, and the Earth and the Moon, let alone explanations for things such as apparent retrograde motion. Some descriptions actually require the sun to be quite small and quite close to the Earth, or else that its light cone be really narrow for some reason.
3. Midnight sun at both the South and North Poles at opposite ends of the year. The geometry proposed by the Flat Earth Society precludes midnight sun in the souther hemisphere.
4. Commercial flights between South America and Australia are polar routes.
https://en.wikipedia.org/wiki/File:PolarRoute.png
(There's fewer routes because there's less land in the Southern Hemisphere, so landmasses are further apart.)
Again, the FES geometry can't explain this. That geometry implies that the shortest route from South America to Australia is North-bound, and it would be impossible in a single hop.
5. The stars in the sky appear to rotate around two points: one above each Pole. On a flat Earth, they would either have to be stationary or else rotate around a single point at one Pole; at the opposite Pole they would appear to rotate quite fast (tangential speed twice that observe at the equator).
6. Tides are incomprehensible if you assume the Earth is flat.
7. Invariably a flat Earth theory requires a conspiracy to hide the true shape of the Earth, but no one can ever put forth a rational motivation for the conspiracy ("for the evulz" isn't rational), let alone actual evidence that it actually exists.




Experimental Gravitational Physics Anonymous 19/01/14(Mon)01:57 No. 16738 ID: b72b93 [Reply]
16738

File 154742745126.jpg - (24.39KB , 700x368 , ligo_background-large-white.jpg )

Any postgrads here who do this stuff?
I've always been more of a mathy guy but now I'm considering joining the group at my uni. They do stuff with LIGO mostly.
Just wondering if there is promise in this field. Cause I'm hesitant about continuing with theoretical physics.




Homosexuality, could it be an anomaly in brain developement? Dr. Nick Riviera 15/02/05(Thu)04:59 No. 16039 ID: 8ec688 [Reply]
16039

File 14231087868.png - (64.35KB , 320x307 , Dr__Riviera.png )

Hi guys, to begin I just want to make a couple of things clear.

- This thread is NOT about discrimination of homosexuals.
- This thread is NOT about considering homosexuality as disease.
- This thread is for pure scientific discussion.

Well, let me begin by telling you that I'm a med student and a embriology assistant at my university and I'm not a native english speaker, so you may encounter some grammatical errors in the text, but you'll get the point.
This whole dilemma began two weeks ago, when my brother told my family that he is gay. It was quite a shock, not because of the fact of him being gay but because he doesn't fit the gay man stereotype. He's a big dude, loves sports, bearded, the true definition of what some call "manly man". We accepted him, of course, and I have to say I've never seen him happier.
But after a few days I began to think, was he always gay? Did he decided to be gay? Why now? These questions started lingering in my mind. So I went to talk with my him about it.
He told me that he always has been, for as long as he remembers. Nothing has changed about him, except for his sexuality (for us, not for him haha). So that got me even MORE questions. Why are some gay men that are like extremely feminine? Why are some gay women extremely masculine? Why are gay guys like my brother who don't appear to be gay? Why do some gay people feel like they are traped inside the other genders body and need to get medical treatment (sex change surgery, hormone therapy) and why others don't?And why are there women like that too? Why many species, whose main goal is to survive (actually this is every species main goal, it's literally in our DNA), has certain individuals who are the contrary to this?
So I decided to tackle all these matters from a scientific point of view? What if during the development of the lymbic system (the part of the brain which controles emotions, memory, sexual desire, etc.) something doesn't go as it should?
So after I thought of this I told myself I couldn't be the first one to ask myself these questions. And of course I wasn't in a world with 7 billion people so thanks to the magical power of the internet I managed to get a cool text about the subject. I took some paragraphs which I thought were the most interesting, still I'm leaving the link (please don't take the text as discriminatory, it's merely scientific, it refers to homosexuality as an anomaly in brain developement because seen from a medical point of view it is, still doesn't mean it's moraly wrong).

"..the body and the brain first become sexually differentiated at about the third fetal month. Prior to this age, although genetically male or female, the fetus is physically/sexually-neutral. With the formation of the testes, and the secretion of testicular androgen, target ti Message too long. Click here to view the full text.


29 posts and 1 image omitted. Click Reply to view.
>>
Anonymous 18/06/28(Thu)13:24 No. 16669 ID: c6e9b2

>>16652
Who cares? Homophobes causes much more problems than the opposite.


>>
Anonymous 18/11/12(Mon)09:57 No. 16720 ID: 0dfe17

>>16577
wow faggots


>>
Anonymous 18/12/27(Thu)15:45 No. 16734 ID: d4b8d9

>>16039
There probably are many homosexuals whose preference could be attributed to divergent fetal development, but given how subjectively humans are able to perceive reality, it's just as likely many homosexuals are simply more interested in their own sex.

In the end, whether you consider it to be brain damage or the whims of the heart doesn't matter; we have not yet developed the technology to ensure the masculization process completes nor have we developed the science to fully account for the subjective differences in people's worldviews. The former we may achieve at some point, but the latter is inherently impossible.

Someday (rather soon), we're going to have Gattica-style designer babies, but we will never "cure" homosexuality.




Genetic Philanthropy - Genetophil Anonymous 18/09/29(Sat)17:53 No. 16698 ID: ed3f35 [Reply]
16698

File 153823642149.jpg - (76.75KB , 1280x720 , genes.jpg )

Why not create a charity to raise IQs in third world nations? Some leading experts say genetics account for 80% of IQ by the time you're 18. The average IQ is dropping worldwide. Would it be ethical to increase IQ through genetic engineering?


4 posts and 1 image omitted. Click Reply to view.
>>
Anonymous 18/10/08(Mon)20:26 No. 16704 ID: be6f8f

>>16702
I think you have cause and effect inverted. It's not that rich people want poor people so they can apply certain economic policies, it's that certain economic policies applied by rich people cause other people to be poorer. Basically, a society where some participants believe they should get wealthier without end inevitably leads to economic inequality.


>>
Anonymous 18/10/22(Mon)09:20 No. 16710 ID: 848b2c

IQ is largely irrelevant to economic productivity and almost COMPLETELY irrelevant to social power; just look who we have in the White House if you're tempted to disagree (or who we MIGHT HAVE HAD, if you still do). Take a black child out of poverty and stick them in a wealthy Western household with a proper education and a diet composed of more than literal garbage, and they will grow up to be a productive adult.

That said, an IQ test measures little more than your proficiency at taking IQ tests. It was NEVER a measure of intelligence; it was a measure of educational achievement as a tool to focus on struggling schoolchildren with poor learning ability, and at best has a tenuous connection with adult intelligence except in extreme cases (like profound retardation: <20IQ). Studies have shown that people with higher IQs don't achieve more as adults but for statistically insignificant amounts.

So you could do this, sure, but nothing would change. The only thing that will is waiting for most of them to die, and then raising the living conditions up to a Western standard for the survivors. Doing it BEFORE letting them die is more humane, sure, but will probably collapse the global economy by the end of the century, likely leading to widespread war and the end of civilization. There's just too fucking many of them.


>>
Anonymous 18/11/10(Sat)12:56 No. 16719 ID: c6e9b2

>>16710
I cant' totally agree. Yes, most westerners wouldn't just breeze trough the life in the average african village. Stirling paints in Islands in The Sea of Time a vivid picture of the back-breaking work needed to grow your own crops.

Their intelligence may help them work more organized, but the raw strength is what matters. - As in all agrarian societies.

But in modern societies general intelligence (g) is more important than raw strength. And there's no link between general intelligence and industriousness (i).

I score high on g, but really low on i (just ask the tax authorities). And you can never disregard the society someone lives in.




Deductive, inductive or abductive? Anonymous 18/07/24(Tue)12:27 No. 16679 ID: c6e9b2 [Reply]
16679

File 153242807199.png - (799.65KB , 1770x2328 , thinker.png )

Hello /sci/!

Yesterday when I took a walk, I saw a bunch of huge plastic containers by the roadside in a shallow natural pit.

I considered it to be a trash dump.

What kind of reasoning did I use. Deductive, inductive or abductive?

And if I used the other two kinds of reasoning, would I reach the same conclusion? And how would I use them?


5 posts omitted. Click Reply to view.
>>
Anonymous 18/10/29(Mon)10:50 No. 16715 ID: be674a

>>16714
>I assumed OP was talking about plastic dumpsters
There is no such thing as plastic dumpsters. They make them out of steel because plastic in that size is not structurally sound enough. Also, why would there be dumpsters on the side of the road in the first place? It still raises the same question of who put them there, and for what purpose.


>>
Anonymous 18/11/01(Thu)22:02 No. 16716 ID: 80b009

>>16715
>There is no such thing as plastic dumpsters.
All you needed to do was search "plastic dumpster" in Google Images to fact-check yourself.

>Also, why would there be dumpsters on the side of the road in the first place?
The point of a dumpster is that a garbage truck can pick it up and empty it. Garbage trucks generally drive on roads, so the logical place to put a dumpster, if it's desirable that a garbage truck can reach it, is as close to the road as possible.


>>
Anonymous 18/11/07(Wed)07:46 No. 16718 ID: dc714c

>>16716
>they actually do make plastic dumpsters
Color me surprised Pedantic: they have a plastic shell and steel reinforcement. And while you're technically correct, it doesn't change that those that I saw are smaller containers, generally for household rather than commercial/industrial use. Most people do not BUY dumpsters; they rent them from the garbage company who picks up the garbage from them on a set schedule, and those dumpsters ARE made of steel. 99% of the dumpsters you're going to see are made of metal; personally I've never seen one of these plastic ones. You're begging to put holes in the fucking thing because people throw concrete chunks and shit in there.

I'm sure there's some retard online out there selling dumpsters made of wood or who has made one of papier mache as an art project. But that changes nothing. OP never stated "dumpsters" to begin with, which would be fairly obvious given that they have a distinctive shape. So one could conclude these "containers" likely were not dumpster-shaped.

>the logical place to put a dumpster, if it's desirable that a garbage truck can reach it, is as close to the road as possible
But not randomly on the side of a road where there's nothing else! There's no trash sitting around there to put IN the containers in the first place. If there were a warehouse or a restaurant right next to it, then it would make sense. But that definitely would not be a "trash dump", it would be "a little concrete pad on their property where sit the dumpsters".




dtyjhty HELP yutyjtry 18/11/03(Sat)21:11 No. 16717 ID: c2ed95 [Reply]
16717

File 154127591658.png - (4.57KB , 225x225 , pfp.png )

Error: An OpMode with the name 'Pushbot: Auto Drive by Encoder' is already registered; ignoring duplicate opmode.




EXPERIMENT Anonymous 18/10/19(Fri)20:34 No. 16708 ID: 9166cf [Reply]
16708

File 153997405955.jpg - (121.05KB , 888x632 , help ME.jpg )

HELP ME


>>
Anonymous 18/10/20(Sat)04:16 No. 16709 ID: 1e5fb7

God be with you on that shit man.




Binomial Irgendwas Anonymous 18/09/11(Tue)02:39 No. 16694 ID: f54f31 [Reply]
16694

File 153662638063.jpg - (29.41KB , 331x400 , confused1.jpg )

I have a question with regards to what I would call a particular object that enumerates the elements of a binomial coefficient. Let me explain the thing first.

Lets say I have 6 elements and I'd like to choose 4 of the stupid things. The binomial coefficient tells me that there are 15 of these groupings. I.e. these:
{{1,2,3,4},{1,2,3,5},{1,2,3,6},{1,2,4,5},{1,2,4,6},
{1,2,5,6},{1,3,4,5},{1,3,4,6},{1,3,5,6},{1,4,5,6},
{2,3,4,5},{2,3,4,6},{2,3,5,6},{2,4,5,6},{3,4,5,6}}
I would like to enumerate over these groupings; and I have an object that does.

My question then is, what would I call the thing that enumerates over those groupings?
Binomial Enumerator?


>>
Anonymous 18/09/11(Tue)18:27 No. 16695 ID: be6f8f

The technical term for each of those "groupings" as you call them is "combination". The action of picking combinations is usually called "choosing" (e.g. 6C4 is read "6 choose 4").
So you could call the enumerator "combination enumerator", "combinator", or "chooser". I think those are all acceptable names.




Atmospheric absorption/scattering of sunlight Anonymous 18/07/27(Fri)04:35 No. 16685 ID: 953c1f [Reply]
16685

File 153265890490.png - (96.72KB , 620x359 , solar-panels-australia.png )

Hey, /sci/. I'm running a simulation of solar panel efficiency and I need some way to calculate energy production from the sun's position in the sky. For example, assuming a panel that is always pointer at the sun, when the sun is closer to the horizon the panel will generate less energy than when it's high in the sky.

I'm looking for something like f(x radians) = y W/m^2.

Thanks.


>>
Anonymous 18/07/27(Fri)04:50 No. 16686 ID: 953c1f
16686

File 15326598517.png - (21.74KB , 1115x717 , theta.png )

Here's part of what I'm doing. Assuming a panel can rotate side to side and track the sun, but cannot rotate up and down, these are the angles of inclination of the panel for a given latitude that will yield the maximum energy production throughout the year. The problem is that this assumes that as long as you point the panel directly at the sun, you will generate the same amount of power at noon as you would just before dusk. So for example at the equator the optimal angle is predicted to be 42°, rather than something flatter. At the same time, energy production is predicted to be higher in Antarctica (99% efficiency) than at the equator (92%), which is nonsense.





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