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Discovery of vibrant deep-sea life prompts new worries over seabed mining

Nature - issue - Pá, 09/21/2018 - 00:00

Discovery of vibrant deep-sea life prompts new worries over seabed mining

Discovery of vibrant deep-sea life prompts new worries over seabed mining, Published online: 21 September 2018; doi:10.1038/d41586-018-06771-w

“Gummy squirrels,” single-celled organisms the size of softballs and strange worms thrive in a Pacific Ocean zone some considered an underwater desert.

How an atom forms a ‘ghost’ bond with a partner that isn’t there

Nature - issue - Pá, 09/21/2018 - 00:00

How an atom forms a ‘ghost’ bond with a partner that isn’t there

How an atom forms a ‘ghost’ bond with a partner that isn’t there, Published online: 21 September 2018; doi:10.1038/d41586-018-06745-y

Electric and magnetic pulses can fool an electron into reaching out for an illusory atom.

University says prominent food researcher committed academic misconduct

Nature - issue - Pá, 09/21/2018 - 00:00

University says prominent food researcher committed academic misconduct

University says prominent food researcher committed academic misconduct, Published online: 21 September 2018; doi:10.1038/d41586-018-06802-6

Brian Wansink will retire at the end of the academic year, according to Cornell University.

Japan’s asteroid mission drops first rovers onto ‘dumpling’ space rock

Nature - issue - Pá, 09/21/2018 - 00:00

Japan’s asteroid mission drops first rovers onto ‘dumpling’ space rock

Japan’s asteroid mission drops first rovers onto ‘dumpling’ space rock, Published online: 21 September 2018; doi:10.1038/d41586-018-06808-0

The two landers will hop around Ryugu to take pictures and measure temperatures.

Daily briefing: The cruel and futile war on obesity

Nature - issue - Pá, 09/21/2018 - 00:00

Daily briefing: The cruel and futile war on obesity

Daily briefing: The cruel and futile war on obesity, Published online: 21 September 2018; doi:10.1038/d41586-018-06810-6

The human cost of science’s inability to understand obesity, Galileo’s long-lost heretical letter, and our pick of the best images, features and culture from the week in science.

Discovery of Galileo’s long-lost letter shows he edited his heretical ideas to fool the Inquisition

Nature - issue - Pá, 09/21/2018 - 00:00

Discovery of Galileo’s long-lost letter shows he edited his heretical ideas to fool the Inquisition

Discovery of Galileo’s long-lost letter shows he edited his heretical ideas to fool the Inquisition, Published online: 21 September 2018; doi:10.1038/d41586-018-06769-4

Exclusive: Document shows that the astronomer toned down the claims that triggered science history’s most infamous battle — then lied about his edits.

A daily aspirin might not be what the doctor ordered

Nature - issue - Pá, 09/21/2018 - 00:00

A daily aspirin might not be what the doctor ordered

A daily aspirin might not be what the doctor ordered, Published online: 21 September 2018; doi:10.1038/d41586-018-06728-z

A drug taken regularly by half of US adults might raise the risk of serious bleeding.

Changing dynamics of the drug overdose epidemic in the United States from 1979 through 2016

Science - issue - Čt, 09/20/2018 - 19:39

Better understanding of the dynamics of the current U.S. overdose epidemic may aid in the development of more effective prevention and control strategies. We analyzed records of 599,255 deaths from 1979 through 2016 from the National Vital Statistics System in which accidental drug poisoning was identified as the main cause of death. By examining all available data on accidental poisoning deaths back to 1979 and showing that the overall 38-year curve is exponential, we provide evidence that the current wave of opioid overdose deaths (due to prescription opioids, heroin, and fentanyl) may just be the latest manifestation of a more fundamental longer-term process. The 38+ year smooth exponential curve of total U.S. annual accidental drug poisoning deaths is a composite of multiple distinctive subepidemics of different drugs (primarily prescription opioids, heroin, methadone, synthetic opioids, cocaine, and methamphetamine), each with its own specific demographic and geographic characteristics.

Asteroseismic detection of latitudinal differential rotation in 13 Sun-like stars

Science - issue - Čt, 09/20/2018 - 19:39

The differentially rotating outer layers of stars are thought to play a role in driving their magnetic activity, but the underlying mechanisms that generate and sustain differential rotation are poorly understood. We report the measurement using asteroseismology of latitudinal differential rotation in the convection zones of 40 Sun-like stars. For the most significant detections, the stars’ equators rotate approximately twice as fast as their midlatitudes. The latitudinal shear inferred from asteroseismology is much larger than predictions from numerical simulations.

Unlocking P(V): Reagents for chiral phosphorothioate synthesis

Science - issue - Čt, 09/20/2018 - 19:39

Phosphorothioate nucleotides have emerged as powerful pharmacological substitutes of their native phosphodiester analogs with important translational applications in antisense oligonucleotide (ASO) therapeutics and cyclic dinucleotide (CDN) synthesis. Stereocontrolled installation of this chiral motif has long been hampered by the systemic use of phosphorus(III) [P(III)]–based reagent systems as the sole practical means of oligonucleotide assembly. A fundamentally different approach is described herein: the invention of a P(V)-based reagent platform for programmable, traceless, diastereoselective phosphorus-sulfur incorporation. The power of this reagent system is demonstrated through the robust and stereocontrolled synthesis of various nucleotidic architectures, including ASOs and CDNs, via an efficient, inexpensive, and operationally simple protocol.

Measurement of a superconducting qubit with a microwave photon counter

Science - issue - Čt, 09/20/2018 - 19:39

Fast, high-fidelity measurement is a key ingredient for quantum error correction. Conventional approaches to the measurement of superconducting qubits, involving linear amplification of a microwave probe tone followed by heterodyne detection at room temperature, do not scale well to large system sizes. We introduce an approach to measurement based on a microwave photon counter demonstrating raw single-shot measurement fidelity of 92%. Moreover, the intrinsic damping of the photon counter is used to extract the energy released by the measurement process, allowing repeated high-fidelity quantum nondemolition measurements. Our scheme provides access to the classical outcome of projective quantum measurement at the millikelvin stage and could form the basis for a scalable quantum-to-classical interface.

Self-assembly of lattices with high structural complexity from a geometrically simple molecule

Science - issue - Čt, 09/20/2018 - 19:39

Here we report an anomalous porous molecular crystal built of C–H···N-bonded double-layered roof-floor components and wall components of a segregatively interdigitated architecture. This complicated porous structure consists of only one type of fully aromatic multijoint molecule carrying three identical dipyridylphenyl wedges. Despite its high symmetry, this molecule accomplishes difficult tasks by using two of its three wedges for roof-floor formation and using its other wedge for wall formation. Although a C–H···N bond is extremely labile, the porous crystal maintains its porosity until thermal breakdown of the C–H···N bonds at 202°C occurs, affording a nonporous polymorph. Though this nonporous crystal survives even at 325°C, it can retrieve the parent porosity under acetonitrile vapor. These findings show how one can translate simplicity into ultrahigh complexity.

Ancient steroids establish the Ediacaran fossil Dickinsonia as one of the earliest animals

Science - issue - Čt, 09/20/2018 - 19:39

The enigmatic Ediacara biota (571 million to 541 million years ago) represents the first macroscopic complex organisms in the geological record and may hold the key to our understanding of the origin of animals. Ediacaran macrofossils are as "strange as life on another planet" and have evaded taxonomic classification, with interpretations ranging from marine animals or giant single-celled protists to terrestrial lichens. Here, we show that lipid biomarkers extracted from organically preserved Ediacaran macrofossils unambiguously clarify their phylogeny. Dickinsonia and its relatives solely produced cholesteroids, a hallmark of animals. Our results make these iconic members of the Ediacara biota the oldest confirmed macroscopic animals in the rock record, indicating that the appearance of the Ediacara biota was indeed a prelude to the Cambrian explosion of animal life.

Fossils reveal the complex evolutionary history of the mammalian regionalized spine

Science - issue - Čt, 09/20/2018 - 19:39

A unique characteristic of mammals is a vertebral column with anatomically distinct regions, but when and how this trait evolved remains unknown. We reconstructed vertebral regions and their morphological disparity in the extinct forerunners of mammals, the nonmammalian synapsids, to elucidate the evolution of mammalian axial differentiation. Mapping patterns of regionalization and disparity (heterogeneity) across amniotes reveals that both traits increased during synapsid evolution. However, the onset of regionalization predates increased heterogeneity. On the basis of inferred homology patterns, we propose a "pectoral-first" hypothesis for region acquisition, whereby evolutionary shifts in forelimb function in nonmammalian therapsids drove increasing vertebral modularity prior to differentiation of the vertebral column for specialized functions in mammals.

Programmable protein circuits in living cells

Science - issue - Čt, 09/20/2018 - 19:39

Synthetic protein-level circuits could enable engineering of powerful new cellular behaviors. Rational protein circuit design would be facilitated by a composable protein-protein regulation system in which individual protein components can regulate one another to create a variety of different circuit architectures. In this study, we show that engineered viral proteases can function as composable protein components, which can together implement a broad variety of circuit-level functions in mammalian cells. In this system, termed CHOMP (circuits of hacked orthogonal modular proteases), input proteases dock with and cleave target proteases to inhibit their function. These components can be connected to generate regulatory cascades, binary logic gates, and dynamic analog signal-processing functions. To demonstrate the utility of this system, we rationally designed a circuit that induces cell death in response to upstream activators of the Ras oncogene. Because CHOMP circuits can perform complex functions yet be encoded as single transcripts and delivered without genomic integration, they offer a scalable platform to facilitate protein circuit engineering for biotechnological applications.

Engineered CRISPR-Cas9 nuclease with expanded targeting space

Science - issue - Čt, 09/20/2018 - 19:39

The RNA-guided endonuclease Cas9 cleaves its target DNA and is a powerful genome-editing tool. However, the widely used Streptococcus pyogenes Cas9 enzyme (SpCas9) requires an NGG protospacer adjacent motif (PAM) for target recognition, thereby restricting the targetable genomic loci. Here, we report a rationally engineered SpCas9 variant (SpCas9-NG) that can recognize relaxed NG PAMs. The crystal structure revealed that the loss of the base-specific interaction with the third nucleobase is compensated by newly introduced non–base-specific interactions, thereby enabling the NG PAM recognition. We showed that SpCas9-NG induces indels at endogenous target sites bearing NG PAMs in human cells. Furthermore, we found that the fusion of SpCas9-NG and the activation-induced cytidine deaminase (AID) mediates the C-to-T conversion at target sites with NG PAMs in human cells.

New Products

Science - issue - Čt, 09/20/2018 - 19:39

Afraid to fail? Reach out

Science - issue - Čt, 09/20/2018 - 19:39

Comment on "U-Th dating of carbonate crusts reveals Neandertal origin of Iberian cave art"

Science - issue - Čt, 09/20/2018 - 19:39

Hoffmann et al. (Reports, 23 February 2018, p. 912) report the discovery of parietal art older than 64,800 years and attributed to Neanderthals, at least 25 millennia before the oldest parietal art ever found. Instead, critical evaluation of their geochronological data seems to provide stronger support for an age of 47,000 years, which is much more consistent with the archaeological background in hand.

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