mr-brain-1999-blog

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Watch This Native Pollinator Build Her Bee-Jeweled Nest

While honeybees and their buzzing hives and hyper-fertile queens get all the press for pollinating our food supply, the hard-working blue orchard bee is one of 4,000 bee species native to North America that does its solitary work in relative obscurity. That is, until now.

In the video, you can see how this bee builds its nests, alternating mud and a purple nectar-pollen mixture in hollow, skinny spaces. The blue orchard bees are preparing a purple lunch box of sorts for their offspring so they have food to eat in the tunnel. The blue orchard bees’ work looks more like jewelry or even scoops of trendy ube ice cream than a nest.

Research has found that 400 female blue orchard bees are as effective at pollinating almonds as the more than 10,000 bees in a honeybee hive, says Boyle.

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Ahhh friends aren't they nice to have Hey no stop being mean don't u guys fignt now I'm trying to say something good about u folks (at Skifa)

[mr-brain-1999-blog]

Ahmed is my friend too just to note His the one with the glasses btw Yeah I know he's even more glorified than but I mean can't change that so I just need to deal with it (at Skifa)

[mr-brain-1999-blog]

Need for multiple slits

In the previous post we discussed why physicists loved to talk about wavelengths and how the wavelength of a light could be found easily by measuring the angle(theta) between the highest intensity (zero order) and say the ‘nth’ order in a Diffraction grating.

If you have heard about the famous Young’s double slit experiment, a Diffraction grating is a tool which has N slits instead of two.

But why do we need N slits ?

Let’s look at various plot of the intensity of light produced at the screen with different slit configurations to gain a perspective.

Notice how the how the width of the bright spots become narrower as we increase the number of slits:

And the following is how the intensity of light(I) changes with each configuration:

Why is this important to have narrow regions of brightness ?

When you actually perform a double slit experiment, here’s what you would see IRL:

                                     PC: artemiawatson on Tumblr

Yes, you can see the interference pattern, but that looks awful if you want to measure the distance between two peaks. The whole pattern looks so diffused!

We would like a nice and crisp peak in intensity so that we wouldn’t need to work hard to measure the distance between the peak intensities. BUT we just observed previously that just increasing the number of slits seems to get the job done!

So let’s increase the number of slits! A tool that does this is known as a  diffraction grating.

                           Diffraction Grating of different slit sizes

Using one of these gratings, we get the following crisp image of the peaks.

We can now take a ruler and measure the distance between the first maximum and the rest. This makes the measurement of wavelength of light even more easier.

Have a good one!

EDIT: If this still feels bizarre and would like a more visual approach to Diffraction Gratings, we refer you to this MIT video by Shaoul Ezekiel.

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Also wich I saw this before my finals

Why is wavelength important than frequency ?

Whenever you see physicists talking about light, you might have noticed they prefer to use wavelength of the light rather than it’s frequency.

This is not a slip of the tongue and there is a very simple reason to it.

It is convenient to measure the wavelength of light experimentally rather than its frequency.

Take the violet light of wavelength 400nm. If we calculate it’s frequency, it turns out to be:

Why is this a problem?

Can’t we measure 7.5 x 10^14 Hz directly ?* There is a theorem by Nyquist in signal processing which states that:

The minimum rate at which a signal can be sampled without introducing errors, is twice the highest frequency present in the signal.

This means that if you want to measure the frequency of light accurately then you need to be sampling at 2*(7.5 x 10^14) Hz in order to measure it and this is incredibly hard to achieve this instrumentally!

Diffraction Grating

On the other hand, here is how easy it is to measure the wavelength of the light:

Take the source of light and pass it through a diffraction grating.

Measure the angle(theta) between the highest intensity (zero order) and say the ‘nth’ order. (see diagram above).

Use the following formula for the wavelength : **

where, d -  distance between the slits (will be provided by manufacturer of diffraction slit), n - order of the slit, theta- from measurement.

And voila, you have the wavelength of the light. That’s how simple it is to get the wavelength of a source light. Since speed of light is a constant, the frequency of light is found out from the following relation:

In addition to this, you can also derive the energy of a photon using the relation:

And so on and so forth. All of these following from a simple diffraction experiment! That’s why calculating the wavelength of light is so crucial.

Have a good one!

* There are some indirect means to do this. Check this physicsforum page for more.

** How do diffraction gratings work ?

[mr-brain-1999-blog]

Needed that more before my finals

CMV Virus May Boost Our Immune System 

Researchers report the cytomegalovirus may actually boost, not weaken, our immune systems.

“We assumed it would make mice more vulnerable to other infections because it was using up resources and keeping the immune system busy,” Dr. Smithey said.

But that’s not what happens.

When infected with listeria, old mice carrying CMV proved to be tougher than old mice without CMV.

Abstract for “Lifelong CMV infection improves immune defense in old mice by broadening the mobilized TCR repertoire against third-party infection” by Megan J. Smithey, Vanessa Venturi, Miles P. Davenport, Adam S. Buntzman, Benjamin G. Vincent, Jeffrey A. Frelinger, and Janko Nikolich-Žugich in PNAS. Published July 2 2028. doi:10.1073/pnas.1719451115

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😂😂I really hate to say it but it seems as flatearthers are right after all

PS: no they're not

Shape of Earth is an oblate spheroid

As you can see from this dramatic demonstration, the consequence of imparting a rotational velocity to an object is the flattening of object at the poles.

The rotational velocity of Earth is a staggering 1,674.4 km/h  and as a result  bulges at the center by a tiny fraction, as is evident from the following image:

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Get ready for Earth Day by binging “True North”!

This Earth Day, ask yourself - “#WhatWillYouDo to protect our Earth?”

“True North” takes you deep into the Arctic, telling stories of the people, places, and animals living in one of the most remote and rapidly changing parts of our planet.

Watch on Tumblr.

Episode Guide:

Episode 1 | Episode 2 | Episode 3 | Episode 4 | Episode 5 | Episode 6 | Episode 7 |  Episode 8 | Episode 9 | Episode 10 | Episode 11 | Episode 12 | Episode 13 | Episode 14 | Episode 15

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Dr. Tamlin Conner, Psychology Senior Lecturer and lead author, says public health campaigns have historically focused on aspects of quantity for the consumption of fruit and vegetables (such as 5+ a day).

However, the study, just published in Frontiers in Psychology, found that for mental health in particular, it may also be important to consider the way in which produce was prepared and consumed.

“Our research has highlighted that the consumption of fruit and vegetables in their ‘unmodified’ state is more strongly associated with better mental health compared to cooked/canned/processed fruit and vegetables,” she says.

Dr. Conner believes this could be because the cooking and processing of fruit and vegetables has the potential to diminish nutrient levels.

“This likely limits the delivery of nutrients that are essential for optimal emotional functioning.”

More information: Kate L. Brookie et al. Intake of Raw Fruits and Vegetables Is Associated With Better Mental Health Than Intake of Processed Fruits and Vegetables, Frontiers in Psychology (2018). DOI: 10.3389/fpsyg.2018.00487

[mr-brain-1999-blog]

What the .... I don't remember the sun being that bright !!!

When the Internet is down and you waddle outside for the first time…

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Firefighter demonstrates how to put out a kitchen fire

[mr-brain-1999-blog]

Shadows are not always black!

Shadows are absolutely fascinating to play around with.

In this Exploratorium demonstration you can see that a black shadow is only a subset of shadows that can be formed on the screen.

If you have multiple sources of light with different colors, then you can additively combine colors to get shadows of various shades.

In this case where you have multiple sources of light, only when the object blocks off light from all three colored light sources do you get a black shadow.

Since we do not deal with multiple colored sources of light on a daily basis, go ahead, give this simple experiment a try. It’s totally worth it!

Have a good one!

** Other FYP explorations on Shadows :

Can a single point of light always illuminate an entire room ?

On disappearing shadows of Birds and airplanes

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Stained Glass Art by Debbie Copley.

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I don't believe in this mambojambo

But I mean just for sure 😐

[mr-brain-1999-blog]

Captured on Film For the First Time: Microglia Nibbling on Synapses 

For the first time, EMBL researchers have captured microglia nibbling on brain synapses. Their findings show that the special glial cells help synapses grow and rearrange, demonstrating the essential role of microglia in brain development. Nature Communications will publish the results on March 26.

Around one in ten cells in your brain are microglia. Cousins of macrophages, they act as the first and main contact in the central nervous system’s active immune defense. They also guide healthy brain development. Researchers have proposed that microglia pluck off and eat synapses – connections between brain cells – as an essential step in the pruning of connections during early circuit refinement. But, until now, no one had seen them do it.

Open access research for “Microglia remodel synapses by presynaptic trogocytosis and spine head filopodia induction” by Laetitia Weinhard, Giulia di Bartolomei, Giulia Bolasco, Pedro Machado, Nicole L. Schieber, Urte Neniskyte, Melanie Exiga, Auguste Vadisiute, Angelo Raggioli, Andreas Schertel, Yannick Schwab & Cornelius T. Gross in Nature Communications. Published online March 26 2018. doi:10.1038/s41467-018-03566-5

Multiple spine heads send out filopodia (green) converging on one microglia (red), as seen by focused ion beam scanning electron microscopy (FIBSEM). NeuroscienceNews.com image is credited to L. Weinhard, EMBL Rome.

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a recipe for the perfect anime

How to make anime fans cry