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Em 2023: 0 notícias
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Researchers find snake venom complexity is driven by prey diet
Publicado em 21 abril 2021
Diversity in diet plays a role in the complexity of venom in pit vipers such as rattlesnakes, copperheads and cottonmouths.
But new collaborative research by Clemson University scientists found the number of prey species a snake ate did not drive venom complexity. Rather, it was how far apart the prey species were from each other evolutionarily.
“It’s not just diet that drives the variation in venom across snakes. It’s the breadth of diet,” said Christopher Parkinson, [...]
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Study cements age and location of hotly debated skull from early human Homo erectus
Publicado em 15 abril 2021A new study verifies the age and origin of one of the oldest specimens of Homo erectus–a very successful early human who roamed the world for nearly 2 million years. In doing so, the researchers also found two new specimens at the site–likely the earliest pieces of the Homo erectus skeleton yet discovered. Details are published today in the journal Nature Communications. “Homo erectus is the first hominin that we know about that has a body plan more [...]ver notícia -
Use of perovskite will be a key feature of the next generation of electronic appliances
Publicado em 16 março 2021Quantum dots are manmade nanoparticles of semiconducting material comprising only a few thousand atoms. Because of the small number of atoms, a quantum dot’s properties lie between those of single atoms or molecules and bulk material with a huge number of atoms. By changing the nanoparticles’ size and shape, it is possible to fine-tune their electronic and optical properties—how electrons bond and move through the material, and how light is absorbed and emitted by it. Thanks [...]ver notícia -
Model describes interactions between light and mechanical vibration in microcavities
Publicado em 03 março 2021Optomechanical microcavities are extremely small structures with diameters of less than 10 micrometers (about a tenth of a human hair) inside which light and mechanical vibrations are confined. Thanks to their small size and to efficient microfabrication techniques that enable them to hold intense light energy and interact with mechanical waves, microcavities can be used as mass and acceleration sensors and in Raman scattering (a spectroscopy technique deployed to analyze materials, including [...]ver notícia -
Large mammals make soil more fertile in tropical forests
Publicado em 18 janeiro 2021The White-lipped peccary (Tayassu pecari) is a boar-like hoofed mammal found throughout Central and South America. These animals roam the forest in bands of 50 to 100 individuals, eating a wide variety of foods. In Brazil’s Atlantic Rainforest, they prefer the fruit of the jussara palm Euterpe edulis. The jussara is very abundant in this biome, probably thanks to vast amounts of dung, urine, and soil trampling by peccaries as well as tapirs (Tapirus terrestris) and other fruit-eating [...]ver notícia -
Venom glands similar to those of snakes are found for first time in amphibians
Publicado em 05 outubro 2020A group led by researchers at Butantan Institute in Brazil and supported by FAPESP has described for the first time the presence of venom glands in the mouth of an amphibian. The legless animal is a caecilian and lives underground. It has tooth-related glands that, when compressed during biting, release a secretion into its prey—earthworms, insect larvae, small amphibians and snakes, and even rodent pups. A paper reporting the study is published in iScience. “We were analyzing the [...]ver notícia -
Researcher proposes universal mechanism for ejection of matter by black holes
Publicado em 03 setembro 2020Black holes can expel a thousand times more matter than they capture. The mechanism that governs both ejection and capture is the accretion disk, a vast mass of gas and dust spiraling around the black hole at extremely high speeds. The disk is hot and emits light as well as other forms of electromagnetic radiation. Part of the orbiting matter is pulled toward the center and disappears behind the event horizon, the threshold beyond which neither matter nor light can escape. Another, much larger, [...]ver notícia -
Researchers develop flat lens a thousand times thinner than a human hair
Publicado em 25 agosto 2020A lens that is a thousand times thinner than a human hair has been developed in Brazil by researchers at the University of São Paulo’s São Carlos School of Engineering (EESC-USP). It can serve as a camera lens in smartphones or be used in other devices that depend on sensors. “In the present technological context, its applications are almost unlimited,” Emiliano Rezende Martins, a professor in EESC-USP’s Department of Electrical Engineering and Computing [...]ver notícia -
Oldest South American fossil lizard discovered in Brazil
Publicado em 30 julho 2020Fossil remains of a novel species of lizard that lived more than 130 million years ago have been found in the north of Minas Gerais, Brazil. It has been named Neokotus sanfranciscanus and is the oldest representatives of the order Squamata ever found in South America. Squamates are the largest reptile group, comprising lizards, snakes and amphisbaenians (worm lizards). The discovery shows that scaled lizards were present on the continent at least 20 million years earlier than previously [...]ver notícia -
Researchers develop an optical fiber made of gel derived from marine algae
Publicado em 28 julho 2020An optical fiber made of agar has been produced at the University of Campinas (UNICAMP) in the state of São Paulo, Brazil. This device is edible, biocompatible and biodegradable. It can be used in vivo for body structure imaging, localized light delivery in phototherapy or optogenetics (e.g., stimulating neurons with light to study neural circuits in a living brain), and localized drug delivery. Another possible application is the detection of microorganisms in specific organs, in which [...]ver notícia