About 200 shops set to begin operations tomorrow; all vehicles to be sanitised

Why has Koyambedu been so badly affected in all stages of the pandemic response?

Fund house held sizeable market share in individual investors' segment

After touching its one-year low of ₹233.8, Marico has recovered 30 per cent. Its ‘defensive’ tag as a supplier of essential goods during the lockdown

Maharashtra has the highest number of cases with around 20,228 positive cases of infection and 779 deaths.

The X-ray diffraction/X-ray fluorescence instrument CheMin on the Curiosity rover is a shoebox-sized device using transmission geometry and an energy-discriminating CCD detector. The instrument has returned the first X-ray diffraction data for soil and drilled samples from Mars outcrops, revealing a suite of primary basaltic minerals, amorphous components and varied hydrous alteration products including phyllosilicates.

The enzyme 4-hydroxy-tetrahydrodipicolinate synthase (DapA) is involved in the production of lysine and precursor molecules for peptidoglycan synthesis. In a multistep reaction, DapA converts pyruvate and l-aspartate-4-semialdehyde to 4-hydroxy-2,3,4,5-tetrahydrodipicolinic acid. In many organisms, lysine binds allosterically to DapA, causing negative feedback, thus making the enzyme an important regulatory component of the pathway. Here, the 2.1 Å resolution crystal structure of DapA from the thermoacidophilic methanotroph Methylacidiphilum fumariolicum SolV is reported. The enzyme crystallized as a contaminant of a protein preparation from native biomass. Genome analysis reveals that M. fumariolicum SolV utilizes the recently discovered aminotransferase pathway for lysine biosynthesis. Phylogenetic analyses of the genes involved in this pathway shed new light on the distribution of this pathway across the three domains of life.

The title compound (systematic name: bis­{[2-(4-hy­droxy-1H-indol-3-yl)eth­yl]bis­(propan-2-yl)aza­nium} but-2-enedioate tetra­hydrate), 2C16H25N2O+·C4H2O42−·4H2O, has a singly protonated DPT cation, one half of a fumarate dianion (completed by a crystallographic centre of symmetry) and two water mol­ecules of crystallization in the asymmetric unit. A series of N—H⋯O and O—H⋯O hydrogen bonds form a three-dimensional network in the solid state.

The title compound (systematic name: bis­{2-[4-(acet­yloxy)-1H-indol-3-yl]ethan-1-aminium} but-2-enedioate), 2C14H19N2O2+·C4H2O42−, has a single protonated psilacetin cation and one half of a fumarate dianion in the asymmetric unit. There are N—H⋯O hydrogen bonds between the ammonium H atoms and the fumarate O atoms, as well as N—H⋯O hydrogen bonds between the indole H atoms and the fumarate O atoms. The hydrogen bonds hold the ions together in infinite one-dimensional chains along [111].

The title compounds, 8-amino-6-methyl-3,4-diphenyl-1H-isochromen-1-one, C22H17NO2, (I), and 8-amino-3,4-diethyl-6-methyl-1H-isochromen-1-one, C14H17NO2, (II), are new isocoumarin derivatives in which the isochromene ring systems are planar. Compound II crystallizes with two independent mol­ecules (A and B) in the asymmetric unit. In I, the two phenyl rings are inclined to each other by 56.41 (7)° and to the mean plane of the 1H-isochromene ring system by 67.64 (6) and 44.92 (6)°. In both compounds, there is an intra­molecular N—H⋯O hydrogen bond present forming an S(6) ring motif. In the crystal of I, mol­ecules are linked by N—H⋯π inter­actions, forming chains along the b-axis direction. A C—H⋯π inter­action links the chains to form layers parallel to (100). The layers are then linked by a second C—H⋯π inter­action, forming a three-dimensional structure. In the crystal of II, the two independent mol­ecules (A and B) are linked by N—H⋯O hydrogen bonds, forming –A–B–A–B– chains along the [101] direction. The chains are linked into ribbons by C—H⋯π inter­actions involving inversion-related A mol­ecules. The latter are linked by offset π–π inter­actions [inter­centroid distances vary from 3.506 (1) to 3.870 (2) Å], forming a three-dimensional structure.

The solid-state structures of the salts of two substituted tryptamines, namely N-isopropyl-N-methyl­tryptaminium (MiPT) fumarate {systematic name: [2-(1H-indol-3-yl)eth­yl](meth­yl)propan-2-yl­aza­nium 3-carb­oxy­prop-2-enoate}, C14H21N2+·C4H3O4−, and 4-hy­droxy-N-isopropyl-N-methyl­tryptaminium (4-HO-MiPT) fumarate monohydrate {systematic name: [2-(4-hy­droxy-1H-indol-3-yl)eth­yl](meth­yl)propan-2-yl­aza­nium 3-carb­oxy­prop-2-enoate monohydrate}, C14H21N2O+·C4H3O4−·H2O, are reported. Both salts possess a proton­ated tryptammonium cation and a 3-carb­oxy­acrylate (hydrogen fumarate) anion in the asymmetric unit; the 4-HO-MiPT structure also contains a water mol­ecule of crystallization. Both cations feature disorder of the side chain over two orientations, in a 0.630 (3):0.370 (3) ratio for MiPT and a 0.775 (5):0.225 (5) ratio for 4-HO-MiPT. In both extended structures, N—H⋯O and O—H⋯O hydrogen bonds generate infinite two-dimensional networks.

The title compound, bis­(4-hy­droxy-N-isopropyl-N-methyl­tryptammonium) (4-HO-MiPT) fumarate (systematic name: bis­{[2-(4-hy­droxy-1H-indol-3-yl)eth­yl](meth­yl)propan-2-yl­aza­nium} but-2-enedioate), 2C14H21N2O+·C4H2O42−, has a singly protonated tryptammonium cation and one half of a fumarate dianion in the asymmetric unit. The tryptammonium and fumarate ions are held together in one-dimensional chains by N—H⋯O and O—H⋯O hydrogen bonds. These chains are a combination of R42(20) rings, and C22(15) and C44(30) parallel chains along (110). They are further consolidated by N—H⋯π inter­actions. There are two two-component types of disorder impacting the tryptammonium fragment with a 0.753 (7):0.247 (7) occupancy ratio and one of the fumarate oxygen atoms with a 0.73 (8):0.27 (8) ratio.

The solid-state structures of the naturally occurring psychoactive tryptamine norpsilocin {4-hy­droxy-N-methyl­tryptamine (4-HO-NMT); systematic name: 3-[2-(methyl­amino)­eth­yl]-1H-indol-4-ol}, C11H14N2O, and its fumarate salt (4-hy­droxy-N-methyl­tryptammonium fumarate; systematic name: bis­{[2-(4-hy­droxy-1H-indol-3-yl)eth­yl]methyl­aza­nium} but-2-enedioate), C11H15N2O+·0.5C4H2O42−, are reported. The freebase of 4-HO-NMT has a single mol­ecule in the asymmetric unit joined together by N—H⋯O and O—H⋯O hydrogen bonds in a two-dimensional network parallel to the (100) plane. The ethyl­amine arm of the tryptamine is modeled as a two-component disorder with a 0.895 (3) to 0.105 (3) occupancy ratio. The fumarate salt of 4-HO-NMT crystallizes with a tryptammonium cation and one half of a fumarate dianion in the asymmetric unit. The ions are joined together by N—H⋯O and O—H⋯O hydrogen bonds to form a three-dimensional framework, as well as π–π stacking between the six-membered rings of inversion-related indoles (symmetry operation: 2 − x, 1 − y, 2 – z).

For Heusler-type Ni–Mn–Ga ferromagnetic shape-memory alloys, the configuration of the martensite variants is a decisive factor in achieving a large magnetic shape-memory effect through field-induced variant reorientation. Based upon the spatially resolved electron backscatter diffraction technique, the microstructural evolution associated with the martensitic transformation from austenite to seven-layered modulated (7M) martensite was investigated on a polycrystalline Ni53Mn22Ga25 alloy. It was clearly shown that grain interior nucleation led to the formation of diamond-shaped 7M martensite within the parent austenite matrix. This diamond microstructure underwent further growth through an isotropic expansion with the coordinated outward movement of four side habit planes, followed by an anisotropic elongation with the forward extension of a type-I twin pair. A two-step growth model is proposed to describe the specific morphology and crystallography of 7M martensite. In addition, the habit planes were revealed to possess a stepped structure, with the {1 0 1}A plane as the terrace and the {0 1 0}A plane as the step. The characteristic combination of martensite variants and the underlying mechanism of self-accommodation in the martensitic transformation have been analysed in terms of the minimum total transformation strain, where the deformation gradient matrix was constructed according to the experimentally determined orientation relationship between the two phases. The present results may deepen the understanding of special martensite microstructures during the martensitic transformation in ferromagnetic shape-memory alloys.

Synchrotron X-ray diffraction (XRD) measured on the XMaS beamline at the ESRF was used to characterize the alloy composition and crystalline surface corrosion of three copper alloy Tudor artefacts recovered from the undersea wreck of King Henry VIII's warship the Mary Rose. The XRD method adopted has a dynamic range ∼1:105 and allows reflections <0.002% of the height of major reflections in the pattern to be discerned above the background without smoothing. Laboratory XRD, scanning electron microscopy–energy dispersive spectroscopy, synchrotron X-ray fluorescence and X-ray excited optical luminescence–X-ray near-edge absorption structure were used as supporting techniques, and the combination revealed structural and compositional features of importance to both archaeology and conservation. The artefacts were brass links believed to be fragments of chainmail and were excavated from the seabed during 1981 and 1982. Their condition reflects very different treatment just after recovery, viz. complete cleaning and conservation, chemical corrosion inhibition and chloride removal only, and distilled water soaking only (to remove the chlorides). The brass composition has been determined for all three at least in the top 7 µm or so as Cu(73%)Zn(27%) from the lattice constant. Measurement of the peak widths showed significant differences in the crystallite size and microstrain between the three samples. All of the links are found to be almost chloride-free with the main corrosion products being spertiniite, sphalerite, zincite, covellite and chalcocite. The balance of corrosion products between the links reflects the conservation treatment applied to one and points to different corrosion environments for the other two.

Insights were obtained into the structure of the 4-hydroxy-tetrahydrodipicolinate synthase from the thermoacidophilic methanotroph Methylacidiphilum fumariolicum SolV and the phylogeny of the aminotransferase pathway for the biosynthesis of lysine.

A major new exhibition hall dedicated to the discovery and understanding of human origins will open next year at the Smithsonian's National Museum of Natural History: The David H. Koch Hall of Human Origins

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The John Marshall Ju/'hoan Bushman Film and Video Collection, 1950-2000, was among 35 documentary heritage items of exceptional value added to UNESCO’s Memory of the World Register in 2009.

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Take to the water with this behind-the-scenes video about Maryland blue crab research at the Smithsonian's Environmental Research Center. Fisheries Ecologist Eric Johnson takes viewers on a journey along the Rhode River to show how scientists tag and monitor Maryland blue crabs in the Chesapeake Bay watershed.

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The Martian moons, Phobos and Deimos, may have been the result of a giant impact that sent rocks and debris into orbit around Mars, instead of asteroids that were captured by the planet’s gravity as previously thought.

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Funded by BP through the Florida Institute of Oceanography, the scientists will make the 10-day trip aboard the institute’s 115-foot research vessel. The divers, scientists and photographers will document hard bottoms of Florida, from the Keys to the Panhandle, to gain a better understanding of these sponge- and coral-dominated communities

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Image right: A sea of dunes, sculpted by the wind into long lines, surrounds the northern polar cap of Mars, covering an area as big […]

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A team of scientists have found that because of this, high summer temperatures have been a strong influence in determining bill size in some birds, particularly species of sparrows that favor salt marshes.

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This is the first report of this invasive species in this area, and may indicate a recent range expansion of the snakehead population.

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Alaska’s pristine coastline is ripe for an influx of invasive marine species such as the European green crab and the rough periwinkle (an Atlantic sea snail) warns a new study by a team of scientists from the Smithsonian Environmental Research Center.

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A new study of marmosets, small South American monkeys, indicates that obesity may begin very early in life and suggests that marmosets may be a helpful model for obesity in humans.

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The Sun’s Active Region 1429 has been shooting off flares and coronal mass ejections since it rotated into Earth’s view on March 2, 2012. Two X-class flares have been released overnight, an X1.3 and an X5.4.

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The only explanation for such symmetry across these vast distances, explains Smithsonian anthropologist Dennis Stanford, is that the method of creating the points was handed down from person to person.

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Recent geologic mapping of the Medusae Fossae Formation on Mars—an intensely eroded deposit near the northern edge of the cratered highlands—has revealed a wider distribution of its western component than was previously recognized.

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Accumulations of drifting snow are the most plausible explanation for the presence of a number of puzzling alluvial fan deposits found inside large impact craters on Mars

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A rising spike in West Nile virus is taking health officials across the country by surprise as this year more than 2,600 people in 45 states and the District of Columbia, have been stricken with severe symptoms of this mosquito-transmitted disease.

The post As robins disperse, West Nile mosquitoes switch diet to humans: Q&A with Smithsonian ornithologist Peter Marra appeared first on Smithsonian Insider.

A new study finds that since 1985, half of Australia's Great Barrier Reef coral has died.

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A rare Longman’s beaked whale found stranded on the Hawaiian island of Maui in 2010 has scientists in Hawaii on the alert for a deadly disease known as morbillivirus which can lead to high mortality rates in dolphins and other marine mammals.

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