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A new study suggests that the biological age of both mouse and human embryos resets during development.
A comet that hasnât zipped past the Sun in millions of years was just discovered and could be one for the record books. Donât worry, itâs steering clear of Earth.
EPFL scientists have developed ultralow-loss silicon nitride integrated circuits that are central for many photonic devices, such as chip-scale frequency combs, narrow-linewidth lasers, coherent LiDAR, and neuromorphic computing.
There are many ways in which humans may one day be able to reach the icy and exotic moon of Saturn known as Titan in just two years, This direct fusion drive holds the most promise.
Livestreaming is a trillion-dollar industry in China, where social networking and entertainment meet marketing and e-commerce. Chinaâs retail economy has become influencer-driven, with almost all online consumers buying products based on recommendations by their idols. That trend has enabled livestreaming and video platforms like Kuaishou and Douyin, which cultivated a roster of hugely popular influencers, to participate in the e-commerce market through partnerships with the online sales platforms.
Many people and businesses would not have survived the pandemic if it were not for the gig economy, says the co-founder of Asia Innovations Group, the start-up behind the live-streaming platform Uplive.
SAN FRANCISCO, June 25 (Reuters) â Microsoft (MSFT.O) said on Friday an attacker had won access to one of its customer-service agents and then used information from that to launch hacking attempts against customers.
The company said it had found the compromise during its response to hacks by a team it identifies as responsible for earlier major breaches at SolarWinds (SWI.N) and Microsoft.
Microsoft said it had warned the affected customers. A copy of one warning seen by Reuters said the attacker belonged to the group Microsoft calls Nobelium and that it had access during the second half of May.
Humans perceive the world around them with five senses â vision, hearing, taste, smell and touch. Many other animals are also able to sense the Earthâs magnetic field. For some time, a collaboration of biologists, chemists and physicists centred at the Universities of Oldenburg (Germany) and Oxford (UK) have been gathering evidence suggesting that the magnetic sense of migratory birds such as European robins is based on a specific light-sensitive protein in the eye. In the current edition of the journal Nature, this team demonstrate that the protein cryptochrome 4, found in birdsâ retinas, is sensitive to magnetic fields and could well be the long-sought magnetic sensor.
First author Jingjing Xu, a doctoral student in Henrik Mouritsenâs research group in Oldenburg, took a decisive step toward this success. After extracting the genetic code for the potentially magnetically sensitive cryptochrome 4 in night-migratory European robins, she was able, for the first time, to produce this photoactive molecule in large quantities using bacterial cell cultures. Christiane Timmelâs and Stuart Mackenzieâs groups in Oxford then used a wide range of magnetic resonance and novel optical spectroscopy techniques to study the protein and demonstrate its pronounced sensitivity to magnetic fields.
The team also deciphered the mechanism by which this sensitivity arises â another important advance. âElectrons that can move within the molecule after blue-light activation play a crucial role,â explains Mouritsen. Proteins like cryptochrome consist of chains of amino acids: robin cryptochrome 4 has 527 of them. Oxfordâs Peter Hore and Oldenburg physicist Ilia Solovâyov performed quantum mechanical calculations supporting the idea that four of the 527 â known as tryptophans â are essential for the magnetic properties of the molecule. According to their calculations, electrons hop from one tryptophan to the next generating so-called radical pairs which are magnetically sensitive. To prove this experimentally, the team from Oldenburg produced slightly modified versions of the robin cryptochrome, in which each of the tryptophans in turn was replaced by a different amino acid to block the movement of electrons.
Submillimeter galaxies (SMGs) are a class of the most luminous, distant, and rapidly star-forming galaxies known and can shine brighter than a trillion Suns (about one hundred times more luminous in total than the Milky Way). They are generally hard to detect in the visible, however, because most of their ultraviloet and optical light is absorbed by dust which in turn is heated and radiates at submillimeter wavelengthsâthe reason they are called submillimeter galaxies. The power source for these galaxies is thought to be high rates of star formation, as much as one thousand stars per year (in the Milky Way, the rate is more like one star per year). SMGs typically date from the early universe; they are so distant that their light has been traveling for over ten billion years, more than 70% of the lifetime of the universe, from the epoch about three billion years after the big bang. Because it takes time for them to have evolved, astronomers think that even a billion years earlier they probably were actively making stars and influencing their environments, but very little is known about this phase of their evolution.
SMGs have recently been identified in galaxy protoclusters, groups of dozens of galaxies in the universe when it was less than a few billion years old. Observing massive SMGs in these distant protoclusters provides crucial details for understanding both their early evolution and that of the larger structures to which they belong. CfA astronomers Emily Pass and Matt Ashby were members of a team that used infrared and optical data from the Spitzer IRAC and Gemini-South instruments, respectively, to study a previosly identified protocluster, SPT2349-56, in the era only 1.4 billion years after the big bang. The protocluster was spotted by the South Pole Telescope millimeter wavelengths and then observed in more detail with Spitzer, Gemini, and the ALMA submillimeter array.
The protocluster contains a remarkable concentration of fourteen SMGs, nine of which were detected by these optical and infrared observations. The astronomers were then able to estimate the stellar masses, ages, and gas content in these SMGs, as well as their star formation histories, a remarkable acheievment for such distant objects. Among other properties of the protocluster, the scientists deduce that its total mass is about one trillion solar-masses, and its galaxies are making stars in a manner similar to star formation processes in the current universe. They also conclude that the whole ensemble is probably in the midst of a colossal merger.
