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We perform magnetohydrodynamic simulations in full general relativity (GRMHD) of quasi-circular, equal-mass, binary neutron stars that undergo merger. The initial stars are irrotational, n = 1 polytropes and are magnetized. We explore two types of magnetic-field geometries: one where each star is endowed with a dipole magnetic field extending from the interior into the exterior, as in a pulsar, and the other where the dipole field is initially confined to the interior. In both cases the adopted magnetic fields are initially dynamically unimportant. The merger outcome is a hypermassive neutron star that undergoes delayed collapse to a black hole (spin parameter a/MBH ~ 0.74) immersed in a magnetized accretion disk. About 4000M ~ 60(MNS/1.625M⊙) ms following merger, the region above the black hole poles becomes strongly magnetized, and a collimated, mildly relativistic outflow-an incipient jet-is launched. The lifetime of the accretion disk, which likely equals the lifetime of the jet, is Δ t ~ 0.1 (MNS/1.625M⊙) s. In contrast to black hole-neutron star mergers, we find that incipient jets are launched even when the initial magnetic field is confined to the interior of the stars.

α(1)-Microglobulin (α(1)m) is a protein of yet unresolved function occurring in blood plasma and urine. It consists of a lipocaline type of fold with two cysteine residues forming a disulfide bridge and the third cysteine-34 remaining a free, somewhat reactive thiol. A number of investigations point to an interaction with heme and we have recently reported, that heme binding triggers the formation of a stable α(1)m trimer upon modification of cysteine-34 with 2-iodoacetamide, i.e., [α(1)m(heme)(2)](3) [J.F. Siebel, R.L. Kosinsky, B. Åkerström, M. Knipp, Insertion of heme b into the structure of the Cys34-carbamidomethylated human lipocalin α(1)-microglobulin-formation of a [(heme)(2)(α(1)-microglobulin)](3) complex, ChemBioChem 13 (2012) 879-887]. For further structural and functional investigations, an improved purification protocol for α(1)m was sought, in particular yielding an untagged amino acid sequence. The method reported herein improves the speed and the yield of the protein production even when an expression plasmid without tag was applied. Furthermore, for the purpose of future structural studies using electron paramagnetic resonance (EPR) techniques, in accordance to the modification with 2-iodoacetamide (α(1)m(AM)), the protein was modified with 3-(2-iodoacetamido)-2,2,5,5-tetramethyl-1-pyrrolidinyloxy (3-(2-iodoacetamido)-PROXYL) yielding the nitroxide spin labeled α(1)m(N-O). The extinction coefficient of the protein was calibrated using magnetic circular dichroism (MCD) spectroscopy of tryptophan (ε(280nm)=40,625M(-1)cm(-1)). The parallel quantification by absorbance spectroscopy (protein) and cw-EPR spectroscopy (radical spin) determined the degree of spin labeling to 90%. Characterization of the protein by circular dichroism (CD) spectroscopy and matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) upon tryptic digestion further demonstrated the similar fold of α(1)m(AM) and α(1)m(N-O), but also established the modification of cystein-34 as well as the formation of the cysteine-72-cysteine-169 disulfide bond.

Scientists have created a silicon chip that can write dozens of DNA sequences simultaneously using electricity and water-based enzymes, offering a cleaner alternative to conventional DNA manufacturing。 The breakthrough could eventually support portable DNA-writing devices and even massive DNA data storage, although new chemistry will be needed to s

NASA's PACE satellite captured the Black Sea glowing turquoise during its annual phytoplankton bloom。 The vivid color comes from massive numbers of coccolithophores, microscopic organisms whose reflective shells brighten the water enough to be seen from space。 An astronaut aboard the International Space Station also photographed the bloom spreading

Don't eat Taco Bell lettuce in Indiana, Kentucky, Michigan, Ohio, or West Virginia

Scientists have developed a new framework that could finally apply the laws of thermodynamics to real, ever-changing black holes instead of only perfectly stable ones。 The advance may improve our understanding of black hole mergers, evaporation, and the powerful gravitational wave events detected by observatories like LIGO

Many will say Spa is the best racetrack on earth, but not for these F1 cars

Pennsylvania cop charged with oppression and obstruction

Used discs are often cheaper than even deep digital discounts

A new study suggests the brain begins making decisions much earlier than scientists previously thought。 Researchers found that even primary sensory regions are influenced by higher brain areas through rapid feedback loops, rather than simply passing information forward。 This more dynamic view of brain function could help engineers design future AI

Dark matter may be far more complicated than scientists once believed。 A new study suggests it could consist of at least two different kinds of particles that slowly separate over time, with heavier particles sinking toward the centers of galaxies and lighter ones drifting outward。 This simple idea could explain several puzzling cosmic observations

Scientists have rewritten the story of gallium after discovering that its unusual atomic bonds re-form at high temperatures, contradicting decades of accepted theory。 The finding changes how researchers explain why the metal melts so easily and behaves unlike almost any other metal。 Beyond solving a long-standing scientific mystery, the work could

The government is piloting a program that uses AI for insurance-coverage decisions

Physicists from Heinrich Heine University Düsseldorf (HHU) have examined a fundamental property of quantum mechanics in collaboration with the German Aerospace Center (DLR)。 In the scientific journal Physical Review Letters, they show that this theory does not necessarily need to be formulated with imaginary numbers – real numbers can in fact also

A new book claims AI has been built on a flawed assumption dating back to Alan Turing's famous 1950 paper。 Denning argues that the most important parts of human intelligence, including common sense, intuition, culture, and practical know-how, cannot be encoded into computers。 He believes this makes true human-level AI impossible, regardless of how

AT&T suffers setback but will keep asking court and FCC to preempt state rules

Researchers have created self-destructing living plastic that uses engineered bacteria to completely break itself down when activated。 The material degrades in just six days without creating microplastics, offering a potential new solution for single-use plastic waste

Monitoring is expensive and labor intensive。 But it helps public health officials stop outbreaks