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The nanoscale circuitry of battery electrodes
Developing high-performance, affordable, and durable batteries is one of the decisive technological tasks of our generation. Here, we review recent progress in understanding how to optimally arrange the various necessary phases to form the nanoscale structure of a battery electrode. The discussion begins with design principles for optimizing electrode kinetics based on the transport parameters and dimensionality of the phases involved. These principles are then used to review and classify various nanostructured architectures that have been synthesized. Connections are drawn to the necessary fabrication methods, and results...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Zhu, C., Usiskin, R. E., Yu, Y., Maier, J. Tags: Materials Science review Source Type: news

Single-stranded DNA and RNA origami
We describe a framework to design and synthesize a single DNA or RNA strand to self-fold into a complex yet unknotted structure that approximates an arbitrary user-prescribed shape. We experimentally construct diverse multikilobase single-stranded structures, including a ~10,000-nucleotide (nt) DNA structure and a ~6000-nt RNA structure. We demonstrate facile replication of the strand in vitro and in living cells. The work here thus establishes unimolecular folding as a general strategy for constructing complex and replicable nucleic acid nanostructures, and expands the design space and material scalability for bottom-up n...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Han, D., Qi, X., Myhrvold, C., Wang, B., Dai, M., Jiang, S., Bates, M., Liu, Y., An, B., Zhang, F., Yan, H., Yin, P. Tags: Materials Science r-articles Source Type: news

Enzyme-free nucleic acid dynamical systems
Chemistries exhibiting complex dynamics—from inorganic oscillators to gene regulatory networks—have been long known but either cannot be reprogrammed at will or rely on the sophisticated enzyme chemistry underlying the central dogma. Can simpler molecular mechanisms, designed from scratch, exhibit the same range of behaviors? Abstract chemical reaction networks have been proposed as a programming language for complex dynamics, along with their systematic implementation using short synthetic DNA molecules. We developed this technology for dynamical systems by identifying critical design principles and codifying ...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Srinivas, N., Parkin, J., Seelig, G., Winfree, E., Soloveichik, D. Tags: Molecular Biology r-articles Source Type: news

My children help my science
(Source: ScienceNOW)
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Grover, S. Tags: Working Life Source Type: news

New Products
(Source: ScienceNOW)
Source: ScienceNOW - December 14, 2017 Category: Science Tags: products Source Type: news

Comprehensive computational design of ordered peptide macrocycles
Mixed-chirality peptide macrocycles such as cyclosporine are among the most potent therapeutics identified to date, but there is currently no way to systematically search the structural space spanned by such compounds. Natural proteins do not provide a useful guide: Peptide macrocycles lack regular secondary structures and hydrophobic cores, and can contain local structures not accessible with l-amino acids. Here, we enumerate the stable structures that can be adopted by macrocyclic peptides composed of l- and d-amino acids by near-exhaustive backbone sampling followed by sequence design and energy landscape calculations. ...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Hosseinzadeh, P., Bhardwaj, G., Mulligan, V. K., Shortridge, M. D., Craven, T. W., Pardo-Avila, F., Rettie, S. A., Kim, D. E., Silva, D.-A., Ibrahim, Y. M., Webb, I. K., Cort, J. R., Adkins, J. N., Varani, G., Baker, D. Tags: Biochemistry reports Source Type: news

Multiplex recording of cellular events over time on CRISPR biological tape
Although dynamics underlie many biological processes, our ability to robustly and accurately profile time-varying biological signals and regulatory programs remains limited. Here we describe a framework for storing temporal biological information directly in the genomes of a cell population. We developed a "biological tape recorder" in which biological signals trigger intracellular DNA production that is then recorded by the CRISPR-Cas adaptation system. This approach enables stable recording over multiple days and accurate reconstruction of temporal and lineage information by sequencing CRISPR arrays. We further...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Sheth, R. U., Yim, S. S., Wu, F. L., Wang, H. H. Tags: Engineering, Molecular Biology reports Source Type: news

Vasohibins encode tubulin detyrosinating activity
Tubulin is subjected to a number of posttranslational modifications to generate heterogeneous microtubules. The modifications include removal and ligation of the C-terminal tyrosine of -tubulin. The enzymes responsible for detyrosination, an activity first observed 40 years ago, have remained elusive. We applied a genetic screen in haploid human cells to find regulators of tubulin detyrosination. We identified SVBP, a peptide that regulates the abundance of vasohibins (VASH1 and VASH2). Vasohibins, but not SVBP alone, increased detyrosination of -tubulin, and purified vasohibins removed the C-terminal tyrosine of -tubulin....
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Nieuwenhuis, J., Adamopoulos, A., Bleijerveld, O. B., Mazouzi, A., Stickel, E., Celie, P., Altelaar, M., Knipscheer, P., Perrakis, A., Blomen, V. A., Brummelkamp, T. R. Tags: Cell Biology, Genetics reports Source Type: news

Vasohibins/SVBP are tubulin carboxypeptidases (TCPs) that regulate neuron differentiation
Reversible detyrosination of α-tubulin is crucial to microtubule dynamics and functions, and defects have been implicated in cancer, brain disorganization, and cardiomyopathies. The identity of the tubulin tyrosine carboxypeptidase (TCP) responsible for detyrosination has remained unclear. We used chemical proteomics with a potent irreversible inhibitor to show that the major brain TCP is a complex of vasohibin-1 (VASH1) with the small vasohibin binding protein (SVBP). VASH1 and its homolog VASH2, when complexed with SVBP, exhibited robust and specific Tyr/Phe carboxypeptidase activity on microtubules. Knockdown of v...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Aillaud, C., Bosc, C., Peris, L., Bosson, A., Heemeryck, P., Van Dijk, J., Le Friec, J., Boulan, B., Vossier, F., Sanman, L. E., Syed, S., Amara, N., Coute, Y., Lafanechere, L., Denarier, E., Delphin, C., Pelletier, L., Humbert, S., Bogyo, M., Andrieux, A Tags: Biochemistry, Cell Biology reports Source Type: news

Analysis of Fusobacterium persistence and antibiotic response in colorectal cancer
Colorectal cancers comprise a complex mixture of malignant cells, nontransformed cells, and microorganisms. Fusobacterium nucleatum is among the most prevalent bacterial species in colorectal cancer tissues. Here we show that colonization of human colorectal cancers with Fusobacterium and its associated microbiome—including Bacteroides, Selenomonas, and Prevotella species—is maintained in distal metastases, demonstrating microbiome stability between paired primary and metastatic tumors. In situ hybridization analysis revealed that Fusobacterium is predominantly associated with cancer cells in the metastatic les...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Bullman, S., Pedamallu, C. S., Sicinska, E., Clancy, T. E., Zhang, X., Cai, D., Neuberg, D., Huang, K., Guevara, F., Nelson, T., Chipashvili, O., Hagan, T., Walker, M., Ramachandran, A., Diosdado, B., Serna, G., Mulet, N., Landolfi, S., Ramon y Cajal, S., Tags: Medicine, Diseases reports Source Type: news

Structural basis of membrane disruption and cellular toxicity by {alpha}-synuclein oligomers
Oligomeric species populated during the aggregation process of α-synuclein have been linked to neuronal impairment in Parkinson’s disease and related neurodegenerative disorders. By using solution and solid-state nuclear magnetic resonance techniques in conjunction with other structural methods, we identified the fundamental characteristics that enable toxic α-synuclein oligomers to perturb biological membranes and disrupt cellular function; these include a highly lipophilic element that promotes strong membrane interactions and a structured region that inserts into lipid bilayers and disrupts their integ...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Fusco, G., Chen, S. W., Williamson, P. T. F., Cascella, R., Perni, M., Jarvis, J. A., Cecchi, C., Vendruscolo, M., Chiti, F., Cremades, N., Ying, L., Dobson, C. M., De Simone, A. Tags: Biochemistry, Neuroscience reports Source Type: news

Poly[n]catenanes: Synthesis of molecular interlocked chains
We report, herein, a synthetic approach toward this distinctive polymer architecture in high yield (~75%) via efficient ring closing of rationally designed metallosupramolecular polymers. Light-scattering, mass spectrometric, and nuclear magnetic resonance characterization of fractionated samples support assignment of the high–molar mass product (number-average molar mass ~21.4 kilograms per mole) to a mixture of linear poly[7–26]catenanes, branched poly[13–130]catenanes, and cyclic poly[4–7]catenanes. Increased hydrodynamic radius (in solution) and glass transition temperature (in bulk materials) w...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Wu, Q., Rauscher, P. M., Lang, X., Wojtecki, R. J., de Pablo, J. J., Hore, M. J. A., Rowan, S. J. Tags: Chemistry, Materials Science reports Source Type: news

Eudicot plant-specific sphingolipids determine host selectivity of microbial NLP cytolysins
Necrosis and ethylene-inducing peptide 1–like (NLP) proteins constitute a superfamily of proteins produced by plant pathogenic bacteria, fungi, and oomycetes. Many NLPs are cytotoxins that facilitate microbial infection of eudicot, but not of monocot plants. Here, we report glycosylinositol phosphorylceramide (GIPC) sphingolipids as NLP toxin receptors. Plant mutants with altered GIPC composition were more resistant to NLP toxins. Binding studies and x-ray crystallography showed that NLPs form complexes with terminal monomeric hexose moieties of GIPCs that result in conformational changes within the toxin. Insensitiv...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Lenarcic, T., Albert, I., Böhm, H., Hodnik, V., Pirc, K., Zavec, A. B., Podobnik, M., Pahovnik, D., Zagar, E., Pruitt, R., Greimel, P., Yamaji-Hasegawa, A., Kobayashi, T., Zienkiewicz, A., Gömann, J., Mortimer, J. C., Fang, L., Mamode-Cass Tags: Biochemistry, Botany reports Source Type: news

Synthesis of ultrasmall, homogeneously alloyed, bimetallic nanoparticles on silica supports
Supported nanoparticles containing more than one metal have a variety of applications in sensing, catalysis, and biomedicine. Common synthesis techniques for this type of material often result in large, unalloyed nanoparticles that lack the interactions between the two metals that give the particles their desired characteristics. We demonstrate a relatively simple, effective, generalizable method to produce highly dispersed, well-alloyed bimetallic nanoparticles. Ten permutations of noble and base metals (platinum, palladium, copper, nickel, and cobalt) were synthesized with average particle sizes from 0.9 to 1.4 nanometer...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Wong, A., Liu, Q., Griffin, S., Nicholls, A., Regalbuto, J. R. Tags: Chemistry, Physics reports Source Type: news

Reducing the stochasticity of crystal nucleation to enable subnanosecond memory writing
Operation speed is a key challenge in phase-change random-access memory (PCRAM) technology, especially for achieving subnanosecond high-speed cache memory. Commercialized PCRAM products are limited by the tens of nanoseconds writing speed, originating from the stochastic crystal nucleation during the crystallization of amorphous germanium antimony telluride (Ge2Sb2Te5). Here, we demonstrate an alloying strategy to speed up the crystallization kinetics. The scandium antimony telluride (Sc0.2Sb2Te3) compound that we designed allows a writing speed of only 700 picoseconds without preprogramming in a large conventional PCRAM d...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Rao, F., Ding, K., Zhou, Y., Zheng, Y., Xia, M., Lv, S., Song, Z., Feng, S., Ronneberger, I., Mazzarello, R., Zhang, W., Ma, E. Tags: Physics, Applied reports Source Type: news

Activation of surface lattice oxygen in single-atom Pt/CeO2 for low-temperature CO oxidation
In this study, we demonstrate how atomically dispersed ionic platinum (Pt2+) on ceria (CeO2), which is already thermally stable, can be activated via steam treatment (at 750°C) to simultaneously achieve the goals of low-temperature carbon monoxide (CO) oxidation activity while providing outstanding hydrothermal stability. A new type of active site is created on CeO2 in the vicinity of Pt2+, which provides the improved reactivity. These active sites are stable up to 800°C in oxidizing environments. (Source: ScienceNOW)
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Nie, L., Mei, D., Xiong, H., Peng, B., Ren, Z., Hernandez, X. I. P., DeLaRiva, A., Wang, M., Engelhard, M. H., Kovarik, L., Datye, A. K., Wang, Y. Tags: Chemistry, Engineering reports Source Type: news

Monitoring and manipulating Higgs and Goldstone modes in a supersolid quantum gas
Higgs and Goldstone modes are collective excitations of the amplitude and phase of an order parameter that is related to the breaking of a continuous symmetry. We directly studied these modes in a supersolid quantum gas created by coupling a Bose-Einstein condensate to two optical cavities, whose field amplitudes form the real and imaginary parts of a U(1)-symmetric order parameter. Monitoring the cavity fields in real time allowed us to observe the dynamics of the associated Higgs and Goldstone modes and revealed their amplitude and phase nature. We used a spectroscopic method to measure their frequencies, and we gave a t...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Leonard, J., Morales, A., Zupancic, P., Donner, T., Esslinger, T. Tags: Physics reports Source Type: news

Disorder-induced optical transition from spin Hall to random Rashba effect
We report on photonic spin-symmetry breaking and unexpected spin-optical transport phenomena arising from subwavelength-scale disordered geometric phase structure. Weak disorder induces a photonic spin Hall effect, observed via quantum weak measurements, whereas strong disorder leads to spin-split modes in momentum space, a random optical Rashba effect. Study of the momentum space entropy reveals an optical transition upon reaching a critical point where the structure’s anisotropy axis vanishes. Incorporation of singular topology into the disordered structure demonstrates repulsive vortex interaction depending on the...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Maguid, E., Yannai, M., Faerman, A., Yulevich, I., Kleiner, V., Hasman, E. Tags: Physics reports Source Type: news

Purcell effect for active tuning of light scattering from semiconductor optical antennas
In this study, we harness the electric and magnetic resonances of such antennas to achieve a very strong dependence of the optical properties on the external environment. Specifically, we illustrate how the resonant scattering wavelength of single silicon nanowires is tunable across the entire visible spectrum by simply moving the height of the nanowires above a metallic mirror. We apply this concept by using a nanoelectromechanical platform to demonstrate active tuning. (Source: ScienceNOW)
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Holsteen, A. L., Raza, S., Fan, P., Kik, P. G., Brongersma, M. L. Tags: Physics reports Source Type: news

Anomalous spin correlations and excitonic instability of interacting 2D Weyl fermions
The Coulomb interaction in systems of quasi-relativistic massless electrons has an unscreened long-range component at variance with conventional correlated metals. We used nuclear magnetic resonance (NMR) measurements to reveal unusual spin correlations of two-dimensional Weyl fermions in an organic material, causing a divergent increase of the Korringa ratio by a factor of 1000 upon cooling, in marked contrast to conventional metallic behavior. Combined with model calculations, we show that this divergence stems from an interaction-driven velocity renormalization that almost exclusively suppresses zero-momentum spin fluct...
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Hirata, M., Ishikawa, K., Matsuno, G., Kobayashi, A., Miyagawa, K., Tamura, M., Berthier, C., Kanoda, K. Tags: Physics reports Source Type: news

Fiber-optic earthquake detection
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Grocholski, B. Tags: twil Source Type: news

When intuition overrides reason
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Chin, G. Tags: twil Source Type: news

Trehalose confers superpowers
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Ash, C. Tags: twil Source Type: news

It just takes one "like"
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Jasny, B. R. Tags: twil Source Type: news

Editing genomes without breaks
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Mao, S. Tags: twil Source Type: news

Mechano-induced mitochondrial fission
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Hurtley, S. M. Tags: twil Source Type: news

Too much alike to be receptive
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Vignieri, S. Tags: twil Source Type: news

Status is not everything
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Pujanandez, L. Tags: twis Source Type: news

Restraining intestinal lymphocyte migration
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Balasubramani, A. Tags: twis Source Type: news

How to save the African elephant
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Fahrenkamp-Uppenbrink, J. Tags: twis Source Type: news

Macrocycles by design
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Vinson, V. Tags: Biochemistry twis Source Type: news

Tubulin carboxypeptidase identity revealed
(Source: ScienceNOW)
Source: ScienceNOW - December 14, 2017 Category: Science Authors: Hurtley, S. M. Tags: Cell Biology, Genetics twis Source Type: news

A little zinc makes the rings all link
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Yeston, J. Tags: Chemistry, Materials Science twis Source Type: news

Dispersing small, bimetallic nanoparticles
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Szuromi, P. Tags: Chemistry, Physics twis Source Type: news

Phase transition of scattered light
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Osborne, I. S. Tags: Physics twis Source Type: news

Breaking the symmetry in a supersolid
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Stajic, J. Tags: Physics twis Source Type: news

Large origami from a single strand
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Szuromi, P. Tags: Materials Science twis Source Type: news

A rationally designed DNA-based oscillator
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Ray, L. B. Tags: Molecular Biology twis Source Type: news

Wired for success
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Lavine, M. S. Tags: Materials Science twis Source Type: news

Finding correlations in a Dirac-cone material
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Stajic, J. Tags: Physics twis Source Type: news

An extra sugar protects
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Hines, P. J. Tags: Biochemistry, Botany twis Source Type: news

How to survive a mass extinction
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Naeem, S. Tags: twis Source Type: news

A CRISPR device to record time
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Mao, S. Tags: Engineering, Molecular Biology twis Source Type: news

A structural look at {alpha}-synuclein oligomers
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Hurtley, S. M. Tags: Biochemistry, Neuroscience twis Source Type: news

Tuning the scattering of light
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Osborne, I. S. Tags: Physics twis Source Type: news

Fast phase change with no preconditions
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Grocholski, B. Tags: Physics, Applied twis Source Type: news

Stable catalysts through steaming
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Szuromi, P. Tags: Chemistry, Engineering twis Source Type: news

Bacteria go the distance in cancer
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Kiberstis, P. A. Tags: Medicine, Diseases twis Source Type: news

Why aging attenuates antiviral responses
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: VanHook, A. M. Tags: twis Source Type: news

Lessons learned from cetacean tragedies
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Source: ScienceNOW - December 14, 2017 Category: Science Authors: Frasier, T. R., Reeves, R. R. Tags: letters Source Type: news