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domenica 25 ottobre 2020

# gst: NikS, a small RNA molecule uses a sort of 'bet-hedging' strategy to survive and infect

<< More than half of the world's population carries the bacterium Helicobacter pylori in their stomach mucosa. It often causes no problems throughout life, but sometimes it can cause inflammation, and in some cases, it can even lead to the development of stomach cancer. Helicobacter pylori uses several 'virulence' factors that allow it to survive in the stomach and can lead to the development of disease. (AA) report that multiple of these factors are centrally regulated by a small RNA molecule called NikS.  >>

<< The fact that Helicobacter pylori can colonize such a hostile environment as the stomach so successfully is also due to a special genetic strategy: Like other pathogens, H. pylori uses a strategy known as phase variation to adapt as flexibly as possible to changes in its environment. Phase variation means that the bacteria constantly switch expression of a gene at random through genetic mutations, meaning that some bacteria in a population will always be ready to express the important gene when it becomes important—a sort of 'bet-hedging' strategy. >>

Robert Emmerich. Small RNA as a central player in infections. University of Würzburg. Oct 15, 2020. 


Sara K. Eisenbart, Mona Alzheimer, et al. A Repeat-Associated Small RNA Controls the Major Virulence Factors of Helicobacter pylori. Mol Cell. vol 80, issue 2, P210-226.E7. doi: 10.1016/ j.molcel.2020.09.009. Oct 15, 2020. 



lunedì 19 ottobre 2020

# ai-bot: use of soft labels with 'less than one'-shot task in AI learning models

<< Deep neural networks require large training sets but suffer from high computational cost and long training times. Training on much smaller training sets while maintaining nearly the same accuracy would be very beneficial. In the few-shot learning setting, a model must learn a new class given only a small number of samples from that class. One-shot learning is an extreme form of few-shot learning where the model must learn a new class from a single example. (AA)  propose the 'less than one'-shot learning task where models must learn N new classes given only M<N examples and (they) show that this is achievable with the help of soft labels. >>

Ilia Sucholutsky, Matthias Schonlau. 'Less Than One'-Shot Learning: Learning N Classes From M<N Samples. arXiv:2009.08449v1. Sep 17, 2020


Karen Hao. A radical new technique lets AI learn with practically no data. Oct 16, 2020.  


FonT: sara' verosimilmente intrigante osservare come una 'macchina AI' sapra' esercitare sugli umani il potere di cooptazione ...


lunedì 12 ottobre 2020

# chem: choose a molecule from an online 'Spotify' for chemistry and synthesize it with a desktop-sized bot

AA << have found a way to create new sets of instructions for robot chemists by harnessing the power of natural language processing. They developed a computer program called SynthReader to scan through scientific papers and recognize sections which outline procedures for organic and inorganic chemical synthesis. Synthreader automatically breaks those procedures down to simple instructions and stores them in a format the team call Chemical Description Language, or XDL, which is a new open source language for describing chemical and material synthesis. Those XDL files are chemical instructions which can in principle be read any chemical robot in. The team built an easy-to-use interface called ChemIDE to integrate with any robotic chemist system and allow the XDL instructions to be turned into chemicals. The only human input required is ensuring that the equipment the robot needs to make the molecules is set up correctly. >>

'Digital chemistry' breakthrough turns words into molecules. University of Glasgow. Oct 2, 2020. 


S. Hessam M. Mehr, Matthew Craven, et al. A universal system for digitization and automatic execution of the chemical synthesis literature. Science. Vol. 370, Issue 6512, pp. 101-108. doi: 10.1126/ science.abc2986. Oct 2, 2020.





giovedì 8 ottobre 2020

# gst: observing the crystallization process in a droplet

<< Crystallization is the assembly of atoms or molecules into highly ordered solid crystals, which occurs in natural, biological, and artificial systems. However, crystallization in confined spaces, such as the formation of the protein shell of a virus, is poorly understood. Researchers are trying to control the structure of the final crystal formed in a confined space to obtain crystals with desired properties, which requires thorough knowledge of the crystallization process. >>

AA << used a droplet of a colloid—a dispersion of liquid particles in another liquid, like milk—as a model for single atoms or molecules in a sphere. Unlike single atoms or molecules, which are too small to easily observe, the colloid particles were large enough to visualize using a microscope. This allowed the researchers to track the ordering of single particles in real time during crystallization. >>

<< We visualized the organization process of colloid particles in numerous droplets under different conditions to provide a picture of the crystallization process in a sphere, >> Peng Tan

<< Based on their observations, the team proposed that the crystallization process involved three stages: initial ordering on the surface "skin" of the droplet, nucleation and growth in the core of the droplet, and then slow ripening of the whole structure. First, a skin consisting of a single layer of ordered colloid particles rapidly formed on the droplet surface. Next, crystallization occurred in the core of the droplet, far from the crystallized skin. The competition between crystallization in these two regions controlled the structure of the final crystal. The researchers found that the "soft" (long-range) interactions between the negatively charged colloid particles affected their organization and the resulting crystal structure. These soft interactions are dominated by kinetics, that is, the interactions that form the fastest, rather than those that use the least energy to give the thermodynamically stable structure, illustrating that kinetics plays an important role in crystallization in a confined space. It was already known that thermodynamics contributes strongly to the final structure of crystals. >>

Having a ball: Crystallization in a sphere. University of Tokyo. Sep 21, 2020.


Chen Y., Yao Z., et al. Morphology selection kinetics of crystallization in a sphere. Nat. Phys. doi: 10.1038/ s41567-020-0991-9. Sep 21, 2020.


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Control of material crystallization by agitation. Osaka University. Jun 08, 2017.


keyword 'drop' or 'droplet' in FonT





mercoledì 7 ottobre 2020

# astro: the turbulent history of Ryugu

<< The asteroid Ryugu may look like a solid piece of rock, but it's more accurate to liken it to an orbiting pile of rubble. >>

<< Ryugu is considered a C-type, or carbonaceous, asteroid, meaning it's primarily composed of rock that contains a lot of carbon and water (..) As expected, most of the surface boulders are also C-type; however, there are a large number of S-type, or siliceous, rocks as well. These are silicate-rich, lack water-rich minerals and are more often found in the inner, rather than outer, solar system. Given the presence of S- as well as C-type rocks on Ryugu, researchers are led to believe the little rubble-pile asteroid likely formed from the collision between a small S-type asteroid and Ryugu's larger C-type parent asteroid.  If the nature of this collision had been the other way around, the ratio of C- to S-type material in Ryugu would also be reversed. >>

Rock types on Ryugu provide clues to the asteroid's turbulent history. University of Tokyo. Sep 21, 2020. 


Tatsumi E., Sugimoto C., et al. Collisional history of Ryugu’s parent body from bright surface boulders. Nat Astron. doi: 10.1038/ s41550-020-1179-z. Sep 21, 2020.


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How small particles could reshape an asteroid. FonT. Sep 26, 2020.





martedì 6 ottobre 2020

# zoo: Tatupa, a random genus name for fixing a rare species of tropical Heteroptera with long antennas

AA << has discovered a new genus and species of bug from the island of Borneo in Southeast Asia. It was named Tatupa grafei and classified as belonging to plant bugs (Miridae). >>

Miridae << are extremely rare in different collections. The fact is that in nature they live in the forest floor and have a cryptic lifestyle. >>

<< Most aspects of the behavior of the Tatupa grafei bugs are unknown due to the extremely small number of its representatives. These insects are often found on fungi growing on rotten wood. Because of this, it has been suggested that these bugs feed on fungi, but whether this is true remains to be explored. It is also possible that Tatupa grafei eats smaller insects, which feed on fungi. The third version is that the bug menu can be mixed and consist of both fungi and insects. >>

<< The genus name Tatupa is a random combination of letters. The scientists could not come up with a suitable name for it for a long time. It was important that no animal has the same name. Additionally, the scientists needed to find out if the word Tatupa exists in any languages and what it means. It turned out that there was only one hit on the Internet—in an episode of a Polish television game where its participants are busy coining new words. The species is named after the Brunei professor Ulmar Grafe, who had provided significant support to the scientists. >>

Entomologists discover a rare species of tropical Heteroptera with long antennae. St. Petersburg State University. Sep 22, 2020. 


Veronica D. Tyts, Anna A. Namyatova, et al. Tatupa grafei, a new genus and species of Cylapinae (Heteroptera, Miridae) from Brunei Darussalam.  ZooKeys 946: 37-52. doi: 10.3897/ zookeys.946.51780. Jul 6, 2020. 





lunedì 28 settembre 2020

# life: oops! aprops of tsunami wave hazards, exposure to other 'Fukushima Daiichi Nuclear Power Plant' accidents appear to exist ...

<< A major tsunami in the northern Arabian Sea could severely impact the coastlines of India and Pakistan, which are studded with sensitive installations including several nuclear plants, >>

<< Atomic power stations functioning along the Arabian Sea include Tarapur (1,400 megawatts) in India's Maharashtra state, Kaiga (being expanded to 2,200 megawatts) in Karnataka state and Karachi in Pakistan (also being expanded to 2,200 megawatts). A mega nuclear power plant coming up at Jaitapur, Maharashtra will generate 9,900 megawatts, while another project at Mithi Virdi in Gujarat may be shelved because of public opposition. >>

<< Nuclear power plants are located along coasts because their enormous cooling needs can be taken care of easily and cheaply by making using abundant seawater. >>

Nuclear plants in Arabian Sea face tsunami risk. SciDev.Net. Sep 21, 2020.


Rajendran, C.P., Heidarzadeh, et al. The Orphan Tsunami of 1524 on the Konkan Coast, Western India, and Its Implications. Pure Appl. Geophys. doi: 10.1007/ s00024-020-02575-0. Sep 7, 2020. 


<< The earthquake had also generated a 14 m high tsunami that arrived shortly afterwards and swept over the plant's seawall and then flooded the lower parts of reactors 1–4. This caused the failure of the emergency generators and loss of power to the circulating pumps.(..) The resultant loss of reactor core cooling led to three nuclear meltdowns, three hydrogen explosions, and the release of radioactive contamination in Units 1, 2 and 3 between 12 and 15 March. >>

Fukushima Daiichi nuclear disaster.  Last edited Sep 25, 2020 by Dougsim.


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2157 - il pino di takata matsubara. Notes. Apr 01, 2011. (quasi-stochastic poetry)


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keyword 'onda' in Notes (quasi-stochastic poetry)


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keyword 'wave' in Font