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Shortform link:
https://shortform.com/artem.

My name is Artem, I’m a computational neuroscience student and researcher.

In this video we will talk about the fundamental role of lognormal distribution in neuroscience. First, we will derive it through Central Limit Theorem, and then explore how it support brain operations on many scales — from cells to perception.

REFERENCES:

1. Buzsáki, G. & Mizuseki, K. The log-dynamic brain: how skewed distributions affect network operations. Nat Rev Neurosci 15264–278 (2014).
2. Ikegaya, Y. et al. Interpyramid Spike Transmission Stabilizes the Sparseness of Recurrent Network Activity. Cerebral Cortex 23293–304 (2013).
3. Loewenstein, Y., Kuras, A. & Rumpel, S. Multiplicative Dynamics Underlie the Emergence of the Log-Normal Distribution of Spine Sizes in the Neocortex In Vivo. Journal of Neuroscience 31, 9481–9488 (2011).
4. Morales-Gregorio, A., van Meegen, A. & van Albada, S. J. Ubiquitous lognormal distribution of neuron densities across mammalian cerebral cortex. http://biorxiv.org/lookup/doi/10.1101/2022.03.17.480842 (2022) doi:10.1101/2022.03.17.480842.

OUTLINE:

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Scientists like to measure things, but they’ve had a heck of a time doing that with sharpness. And even if no one agrees on exactly how to measure it, our search for better tools has recently led to some of the sharpest objects we’ve ever created.

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Sources:
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e=gscholar.
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https://www.sciencefocus.com/science/whats-the-sharpest-knife-in-the-world/

scienceofsharp


https://www.sciencedirect.com/science/article/pii/S0924013604007022
https://www.sciencedirect.com/science/article/pii/S0013794406004073
https://www.scientific.net/KEM.293-294.769
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7BAFBA8B6F
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;0.pdf?pdf.

Images:
https://commons.wikimedia.org/wiki/File: Crater_knife_edge.jpg.

Dual Grit Sharpening


https://www.researchgate.net/figure/Artificial-sapphire-scal
_354874023
https://www.southampton.ac.uk/biu/galleries/sem.page.
https://commons.wikimedia.org/wiki/File: Obsidian_blade_mounted_in_ornamental_handle,_from_Admiralty_Wellcome_M0015133.jpg.
https://commons.wikimedia.org/wiki/File:Blade_MET_VS1994_35_468.jpeg.
https://commons.wikimedia.org/wiki/File:Macro_sewing_machine_needles.jpg.
https://commons.wikimedia.org/wiki/File:Beveled_tip_of_a_hyp
14_005.JPG
https://www.researchgate.net/figure/SEM-image-of-a-carbon-na
2_51450738
https://commons.wikimedia.org/wiki/File:Scanning_Tunneling_M
ematic.svg.
https://commons.wikimedia.org/wiki/File:%D0%9E%D0%B4%D0%BD%D
%D0%B0.jpg.
https://commons.wikimedia.org/wiki/File:Prehistoric_Denmark_
51010).jpg

The breakthrough experiment could lead to low-energy, wave-based computers and new applications for wireless communications.

Researchers at the Advanced Science Research Center at the CUNY Graduate Center (CUNY ASRC) performed a breakthrough experiment in which they observed time reflections of electromagnetic signals in a tailored metamaterial.

Time reflection versus spatial reflection.


Andrea Alu.

The scientists, who published their findings in a paper in Nature Physics, were able to successfully cause time reversal as well as frequency conversion of broadband electromagnetic waves in their experiments.

An international team of researchers, including those from the University of Tokyo’s Institute for Solid State Physics, has made a groundbreaking discovery. They have successfully demonstrated the use of a single molecule named fullerene as a switch, similar to a transistor. The team achieved this by employing a precisely calibrated laser pulse, which allowed them to control the path of an incoming electron in a predictable manner.

The switching process enabled by fullerene molecules can be significantly faster than the switches used in microchips, with a speed increase of three to six orders of magnitude, depending on the laser pulses utilized. The use of fullerene switches in a network could result in the creation of a computer with capabilities beyond what is currently achievable with electronic transistors. Additionally, they have the potential to revolutionize microscopic imaging devices by providing unprecedented levels of resolution.

Over 70 years ago, physicists discovered that molecules emit electrons in the presence of electric fields, and later on, certain wavelengths of light. The electron emissions created patterns that enticed curiosity but eluded explanation. But this has changed thanks to a new theoretical analysis, the ramification of which could not only lead to new high-tech applications but also improve our ability to scrutinize the physical world itself.

Reports say that the Nokia Magic Max will come in three different memory configurations. We will have 8GB, 12GB and 16GB of RAM with 256GB and 512GB storage options. It will launch with Android 13 out of the box with Snapdragon 8 Gen 2 SoC under the hood. We may also see a 6.7-inch AMOLED display with 120Hz refresh rate on the device. Corning Gorilla Glass 7 protection could be on the display of the upcoming flagship device from Nokia.

The device will feature a triple camera setup on the back with 144MP main sensor, 64MP ultrawide and 48MP Telephoto lens. Rumors have suggested a massive 7950mAh battery which can also charge from 0 to 100 within a few minutes, thanks to the 180W fast charger.

The memory configurations will determine the price of each variant. Nevertheless, sources have suggested the starting price to be around $550 (INR44,900). There is no firm rumor with respect to the launch date, but we expect to see the launch of the Nokia Magic Max in a matter of few weeks.

The industry is gaining ground in understanding how aging affects reliability, but more variables make it harder to fix.

Circuit aging is emerging as a first-order design challenge as engineering teams look for new ways to improve reliability and ensure the functionality of chips throughout their expected lifetimes.

The need for reliability is obvious in data centers and automobiles, where a chip failure could result in downtime or injury. It also is increasingly important in mobile and consumer electronics, which are being used for applications such as in-home health monitoring or for navigation, and where the cost of the devices has been steadily rising. But aging also needs to be assessed in the context of variation models from the foundries, different use cases that may stress various components in different ways, and different power and thermal profiles, all of which makes it harder to accurately predict how a chip will behave over time.

Processing more data in more places while minimizing its movement becomes a requirement and a challenge.

Movement and management of data inside and outside of chips is becoming a central theme for a growing number of electronic systems, and a huge challenge for all of them.

Entirely new architectures and techniques are being developed to reduce the movement of data and to accomplish more per compute cycle, and to speed the transfer of data between various components on a chip and between chips in a package. Alongside of that, new materials are being developed to increase electron mobility and to reduce resistance and capacitance.

[Russ Maschmeyer] and Spatial Commerce Projects developed WonkaVision to demonstrate how 3D eye tracking from a single webcam can support rendering a graphical virtual reality (VR) display with realistic depth and space. Spatial Commerce Projects is a Shopify lab working to provide concepts, prototypes, and tools to explore the crossroads of spatial computing and commerce.

The graphical output provides a real sense of depth and three-dimensional space using an optical illusion that reacts to the viewer’s eye position. The eye position is used to render view-dependent images. The computer screen is made to feel like a window into a realistic 3D virtual space where objects beyond the window appear to have depth and objects before the window appear to project out into the space in front of the screen. The resulting experience is like a 3D view into a virtual space. The downside is that the experience only works for one viewer.

Eye tracking is performed using Google’s MediaPipe Iris library, which relies on the fact that the iris diameter of the human eye is almost exactly 11.7 mm for most humans. Computer vision algorithms in the library use this geometrical fact to efficiently locate and track human irises with high accuracy.

Quantum processors are computing systems that process information and perform computations by exploiting quantum mechanical phenomena. These systems could significantly outperform conventional processors on certain tasks, both in terms of speed and computational capabilities.

While engineers have developed several promising quantum computing systems over the past decade or so, scaling these systems and ensuring that they can be deployed on a large-scale remains an ongoing challenge. One proposed strategy to increase the scalability of entails the creation of modular systems containing multiple smaller quantum modules, which can be individually calibrated and then arranged into a bigger architecture. This, however, would require suitable and effective interconnects (i.e., devices for connecting these smaller modules).

Researchers at the Southern University of Science and Technology, the International Quantum Academy and other institutes in China have recently developed low-loss interconnects for linking the individual modules in modular superconducting quantum processors. These interconnects, introduced in Nature Electronics, are based on pure cables and on-chip impendence transformers.