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Conference on Transition to the green economy

This event, with involvement from the OECD, on 6-7 September 2016, is of major strategic nature during the Slovak Presidency of the European Council. Its ambition is to improve understanding of the green economy concept, identify conclusions and pathways for transition as well as to involve and mobilise various actors and stakeholders in the discussions of possible future actions.




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Germany is leading the charts on employment and green growth - Transition to a knowledge based economy will require further reform and investment, OECD says

Germany recovered rapidly from the 2008-09 recession, with GDP topping pre-crisis rates during 2011 and unemployment falling significantly. Public finances are sound, but further reforms are needed to transform its growth model to thrive as a knowledge-based economy.




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Workshop: Indicators of local transition to low-carbon economy (Regional Growth Core Schönefelder Kreuz, Germany)

The Regional Growth Core Schönefelder Kreuz and the Technical University of Applied Sciences Wildau in partnership with the OECD Local Economic and Employment Development Programme (LEED) are working on defining and collecting measurable indicators at the regional/ local level that can inform over time of transition to low-carbon economic and industrial activities.




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Report: Green growth in the Benelux - Indicators of local transition to a low-carbon economy in cross-border regions (Benelux)

This paper discusses the results of the 2011-2012 OECD LEED study of measuring green growth in the Benelux countries (Belgium, The Netherlands and Luxembourg). The study paid particular attention to the challenges of measuring the transition to a low-carbon economy in cross-border areas as they have additional levels of complexity when it comes to measuring and monitoring their low-carbon transition.




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Project: Measuring the potential of green growth: Indicators of local transition to a low-carbon economy

This LEED project aims to to define key indicators of area-based transition to a low-carbon economy. The objective is to define measurable indicators at regional/local level that can inform over time of transition to low-carbon economic and industrial activities.




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Japan can do more to encourage smooth transition of laid-off workers back into jobs, says OECD

Japan could help laid-off workers find a job more quickly by improving co-ordination between public employment services and companies, as well as ensuring that all workers benefit from adequate Employment Insurance (EI) benefits, according to a new OECD report.




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School-to-work transitions in Emerging and Advanced Economies

Improving school-to-work transitions and ensuring better career opportunities for youth after labour market entrance are common goals in emerging and advanced economies as they can contribute to raising the productive potential of the economy and to increasing social cohesion. However, the challenges faced in achieving these objectives and the policies required vary between emerging and advanced economies.




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Register for the webinar - Transitions from Early Childhood Education and Care to Primary Education (Wednesday, 21 June, at 17:00 Paris time)

Join Andreas Schleicher, Director of the OECD Directorate for Education and Skills, and Éric Charbonnier, analyst in the Early Childhood and Schools division, who will present the main findings from Starting Strong V - Transitions from Early Childhood Education and Care to Primary Education.




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Archived webinar - Transitions from Early Childhood Education and Care to Primary Education

The transition from early childhood education to primary school is a big step for all children, and a step which more and more children are having to take. Quality transitions should be well-prepared and child-centred, managed by trained staff collaborating with one another, and guided by an appropriate and aligned curriculum.




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Education Indicators in Focus No. 54 - Transition from school to work: How hard is it across different age groups?

The transition from school to work can be a difficult period associated with spells of unemployment. Data show that those who leave school early have comparatively low skills and low educational attainment and face the greatest challenges in the labour market compared to their peers who stayed in education longer.




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Workshop: Indicators of local transition to low-carbon economy (Regional Growth Core Schönefelder Kreuz, Germany)

The Regional Growth Core Schönefelder Kreuz and the Technical University of Applied Sciences Wildau in partnership with the OECD Local Economic and Employment Development Programme (LEED) are working on defining and collecting measurable indicators at the regional/ local level that can inform over time of transition to low-carbon economic and industrial activities.




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Report: Green growth in the Benelux - Indicators of local transition to a low-carbon economy in cross-border regions (Benelux)

This paper discusses the results of the 2011-2012 OECD LEED study of measuring green growth in the Benelux countries (Belgium, The Netherlands and Luxembourg). The study paid particular attention to the challenges of measuring the transition to a low-carbon economy in cross-border areas as they have additional levels of complexity when it comes to measuring and monitoring their low-carbon transition.




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Project: Measuring the potential of green growth: Indicators of local transition to a low-carbon economy

This LEED project aims to to define key indicators of area-based transition to a low-carbon economy. The objective is to define measurable indicators at regional/local level that can inform over time of transition to low-carbon economic and industrial activities.




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Weight of evidence assessment for the skin sensitisation potential of 4-isopropylaniline

This OECD monograph demonstrates how a chemical hazard assessment that considers and ranks all available relevant information - a so-called weight of evidence approach - can be constructed to conclude on a particular hazard endpoint for a chemical, in this case, skin sensitisation for 4-isopropylaniline.




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Launch of 2 OECD Test Guidelines on human hazard endpoint skin sensitisation

The OECD has just published two new Test Guidelines on human health hazard endpoint skin sensitisation. Skin sensitisation refers to an allergic response following skin contact with the tested chemical, as defined by the United Nations Globally Harmonized System of Classification and Labelling of Chemicals (UN GHS).




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Portrait of an actress as a sensitive woman

Enthralling , engrossing, enticing . Unsurprising for a book whose subject is the supremely beautiful Madhubala. This biography is a good read for those who know little about this gifted actress. Written in an easy, fluid style, with captivating black and white photographs, "I Want to Live" is almost plaintive in its title.




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BMC opens transit homes at city’s entry points




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iQOO Z1 Tipped To Feature Dimensity 1000+ Chipset Dedicated For Gaming

Vivo's sub-brand iQOO has been making a name for itself with a couple of flagship devices like the iQOO Neo 3. More recently, when MediaTek announced the new Dimensity 1000+ chipset, iQOO said it would launch a smartphone with the processor.




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New treatment option for young women with hormone-sensitive breast cancer

A drug used for treating breast cancer, known as exemestane, is more effective than a common breast cancer prevention drug, tamoxifen, in preventing breast cancer recurrence in young women who also receive post-surgical treatment to suppress ovarian function. The combined results of the Tamoxifen and Exemestane Trial and Suppression of Ovarian Function Trial were presented at the 2014 ASCO Annual Meeting in Chicago.




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Cosmologists gain insights into density, structure of matter in universe




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'COVA Punjab' mobile app launched to sensitise people about precautions




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This Chandigarh policeman sensitising people on hygiene




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Contributions of charge-density research to medicinal chemistry

Contributions of experimental and selected theoretical charge-density research to medicinal chemistry are reviewed; combining experimental methods from high-resolution small-molecule and macromolecular crystallography with theory proves to be fruitful.




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Magnetic field-induced magnetostructural transition and huge tensile superelasticity in an oligocrystalline Ni–Cu–Co–Mn–In microwire

Meta-magnetic shape-memory alloys combine ferroelastic order with ferromagnetic order and exhibit attractive multifunctional properties, but they are extremely brittle, showing hardly any tensile deformability, which impedes their practical application. Here, for the first time, an Ni–Cu–Co–Mn–In microwire has been developed that simultaneously exhibits a magnetic field-induced first-order meta-magnetic phase transition and huge tensile superelasticity. A temperature-dependent in situ synchrotron high-energy X-ray diffraction investigation reveals that the martensite of this Ni43.7Cu1.5Co5.1Mn36.7In13 microwire shows a monoclinic six-layered modulated structure and the austenite shows a cubic structure. This microwire exhibits an oligocrystalline structure with bamboo grains, which remarkably reduces the strain incompatibility during deformation and martensitic transformation. As a result, huge tensile superelasticity with a recoverable strain of 13% is achieved in the microwire. This huge tensile superelasticity is in agreement with our theoretical calculations based on the crystal structure and lattice correspondence of austenite and martensite and the crystallographic orientation of the grains. Owing to the large magnetization difference between austenite and martensite, a pronounced magnetic field-induced magnetostructural transition is achieved in the microwire, which could give rise to a variety of magnetically driven functional properties. For example, a large magnetocaloric effect with an isothermal entropy change of 12.7 J kg−1 K−1 (under 5 T) is obtained. The realization of magnetic-field- and tensile-stress-induced structural transformations in the microwire may pave the way for exploiting the multifunctional properties under the coupling of magnetic field and stress for applications in miniature multifunctional devices.




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Spin resolved electron density study of YTiO3 in its ferromagnetic phase: signature of orbital ordering

The present work reports on the charge and spin density modelling of YTiO3 in its ferromagnetic state (TC = 27 K). Accurate polarized neutron diffraction and high-resolution X-ray diffraction (XRD) experiments were carried out on a single crystal at the ORPHÉE reactor (LLB) and SPRING8 synchrotron source. The experimental data are modelled by the spin resolved pseudo-atomic multipolar model (Deutsch et al., 2012). The refinement strategy is discussed and the result of this electron density modelling is compared with that from XRD measured at 100 K and with density functional theory calculations. The results show that the spin and charge densities around the Ti atom have lobes directed away from the O atoms, confirming the filling of the t2g orbitals of the Ti atom. The dxy orbital is less populated than dxz and dyz, which is a sign of a partial lift of degeneracy of the t2g orbitals. This study confirms the orbital ordering at low temperature (20 K), which is already present in the paramagnetic state above the ferromagnetic transition (100 K).




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Charge densities in actinide compounds: strategies for data reduction and model building

The data quality requirements for charge density studies on actinide compounds are extreme. Important steps in data collection and reduction required to obtain such data are summarized and evaluated. The steps involved in building an augmented Hansen–Coppens multipole model for an actinide pseudo-atom are provided. The number and choice of radial functions, in particular the definition of the core, valence and pseudo-valence terms are discussed. The conclusions in this paper are based on a re-examination and improvement of a previously reported study on [PPh4][UF6]. Topological analysis of the total electron density shows remarkable agreement between experiment and theory; however, there are significant differences in the Laplacian distribution close to the uranium atoms which may be due to the effective core potential employed for the theoretical calculations.




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Crystallographic insights into diamond-shaped 7M martensite in Ni–Mn–Ga ferromagnetic shape-memory alloys

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.




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Charge density view on bicalutamide molecular interactions in the monoclinic polymorph and androgen receptor binding pocket

High-resolution single-crystal X-ray measurements of the monoclinic polymorph of bicalutamide and the aspherical atom databank approach have served as a basis for a reconstruction of the charge density distribution of the drug and its androgen receptor (AR) and albumin complexes. The contributions of various types of intermolecular interactions to the total crystal energy or ligand:AR energy were estimated. The cyan and amide groups secured the ligand placement in the albumin (Lys-137) and the AR binding pocket (Leu-704, Asn-705, Arg-752), and also determined the packing of the small-molecule crystals. The total electrostatic interaction energy on average was −230 kJ mol−1, comparable with the electrostatic lattice energy of the monoclinic bicalutamide polymorph. This is the result of similar distributions of electropositive and electronegative regions on the experimental and theoretical molecular electrostatic potential maps despite differences in molecular conformations. In general, bicalutamide interacted with the studied proteins with similar electrostatic interaction energies and adjusted its conformation and electrostatic potential to fit the binding pocket in such a way as to enhance the interactions, e.g. hydrogen bonds and π⋯π stacking.




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Investigation of growth characteristics and semimetal–semiconductor transition of polycrystalline bis­muth thin films

The preferred orientation growth characteristics and surface roughness of polycrystalline bis­muth (Bi) thin films fabricated on glass substrates using the molecular beam epitaxy method were investigated at temperatures ranging from 18 to 150°C. The crystallization and morphology were analyzed in detail and the polycrystalline metal film structure-zone model (SZM) was modified to fit the polycrystalline Bi thin film. The boundary temperature between Zone T and Zone II in the SZM shifted to higher temperatures with the increase in film thickness or the decrease of growth rate. Furthermore, the effect of the thickness and surface roughness on the transport properties was investigated, especially for Bi thin films in Zone II. A two-transport channels model was adopted to reveal the influence of the film thickness on the competition between the metallic surface states and the semiconducting bulk states, which is consistent with the results of Bi single-crystal films. Therefore, the polycrystalline Bi thin films are expected to replace the single-crystal films in the application of spintronic devices.




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Cascading transitions toward unconventional charge density wave states in the quasi-two-dimensional monophosphate tungsten bronze P4W16O56

Single crystals of the m = 8 member of the low-dimensional monophosphate tungsten bronzes (PO2)4(WO3)2m family were grown by chemical vapour transport technique and the high crystalline quality obtained allowed a reinvestigation of the physical and structural properties. Resistivity measurements revealed three anomalies at TC1 = 258 K, TC2 = 245 K and TC3 = 140 K, never observed until now. Parallel X-ray diffraction investigations showed a specific signature associated with three structural transitions, i.e. the appearance of different sets of satellite reflections below TC1, TC2 and TC3. Several harmonics of intense satellite reflections were observed, reflecting the non-sinusoidal nature of the structural modulations and a strong electron–phonon coupling in the material. These transitions could be associated with the formation of three successive unconventional charge density wave states.




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Comparing the backfilling of mesoporous titania thin films with hole conductors of different sizes sharing the same mass density

Efficient infiltration of a mesoporous titania matrix with conducting organic polymers or small molecules is one key challenge to overcome for hybrid photovoltaic devices. A quantitative analysis of the backfilling efficiency with time-of-flight grazing incidence small-angle neutron scattering (ToF-GISANS) and scanning electron microscopy (SEM) measurements is presented. Differences in the morphology due to the backfilling of mesoporous titania thin films are compared for the macromolecule poly[4,8-bis­(5-(2-ethyl­hexyl)­thio­phen-2-yl)benzo[1,2-b;4,5-b']di­thio­phene-2,6-diyl-alt-(4-(2-ethyl­hexyl)-3-fluoro­thieno[3,4-b]thio­phene-)-2-carboxyl­ate-2-6-diyl)] (PTB7-Th) and the heavy-element containing small molecule 2-pinacol­boronate-3-phenyl­phen­anthro[9,10-b]telluro­phene (PhenTe-BPinPh). Hence, a 1.7 times higher backfilling efficiency of almost 70% is achieved for the small molecule PhenTe-BPinPh compared with the polymer PTB7-Th despite sharing the same volumetric mass density. The precise characterization of structural changes due to backfilling reveals that the volumetric density of backfilled materials plays a minor role in obtaining good backfilling efficiencies and interfaces with large surface contact.




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On the mechanism of solid-state phase transitions in molecular crystals – the role of cooperative motion in (quasi)racemic linear amino acids

During single-crystal-to-single-crystal (SCSC) phase transitions, a polymorph of a compound can transform to a more stable form while remaining in the solid state. By understanding the mechanism of these transitions, strategies can be developed to control this phenomenon. This is particularly important in the pharmaceutical industry, but also relevant for other industries such as the food and agrochemical industries. Although extensive literature exists on SCSC phase transitions in inorganic crystals, it is unclear whether their classications and mechanisms translate to molecular crystals, with weaker interactions and more steric hindrance. A comparitive study of SCSC phase transitions in aliphatic linear-chain amino acid crystals, both racemates and quasi-racemates, is presented. A total of 34 transitions are considered and most are classified according to their structural change during the transition. Transitions without torsional changes show very different characteristics, such as transition temperature, enthalpy and free energy, compared with transitions that involve torsional changes. These differences can be rationalized using classical nucleation theory and in terms of a difference in mechanism; torsional changes occur in a molecule-by-molecule fashion, whereas transitions without torsional changes involve cooperative motion with multiple molecules at the same time.




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Experimental charge density of grossular under pressure – a feasibility study

X-ray diffraction studies of crystals under pressure and quantitative experimental charge density analysis are among the most demanding types of crystallographic research. A successful feasibility study of the electron density in the mineral grossular under 1 GPa pressure conducted at the CRISTAL beamline at the SOLEIL synchrotron is presented in this work. A single crystal was placed in a diamond anvil cell, but owing to its special design (wide opening angle), short synchrotron wavelength and the high symmetry of the crystal, data with high completeness and high resolution were collected. This allowed refinement of a full multipole model of experimental electron distribution. Results are consistent with the benchmark measurement conducted without a diamond-anvil cell and also with the literature describing investigations of similar structures. Results of theoretical calculations of electron density distribution on the basis of dynamic structure factors mimic experimental findings very well. Such studies allow for laboratory simulations of processes which take place in the Earth's mantle.




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Noncrystallographic symmetry-constrained map obtained by direct density optimization

Noncrystallographic symmetry (NCS) averaging following molecular-replacement phasing is generally the major technique used to solve a structure with several molecules in one asymmetric unit, such as a spherical icosahedral viral particle. As an alternative method to NCS averaging, a new approach to optimize or to refine the electron density directly under NCS constraints is proposed. This method has the same effect as the conventional NCS-averaging method but does not include the process of Fourier synthesis to generate the electron density from amplitudes and the corresponding phases. It has great merit for the solution of structures with limited data that are either twinned or incomplete at low resolution. This method was applied to the case of the T = 1 shell-domain subviral particle of Penaeus vannamei nodavirus with data affected by twinning using the REFMAC5 refinement software.




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Optimized reconstruction of the crystallographic orientation density function based on a reduced set of orientations

Crystallographic textures, as they develop for example during cold forming, can have a significant influence on the mechanical properties of metals, such as plastic anisotropy. Textures are typically characterized by a non-uniform distribution of crystallographic orientations that can be measured by diffraction experiments like electron backscatter diffraction (EBSD). Such experimental data usually contain a large number of data points, which must be significantly reduced to be used for numerical modeling. However, the challenge in such data reduction is to preserve the important characteristics of the experimental data, while reducing the volume and preserving the computational efficiency of the numerical model. For example, in micromechanical modeling, representative volume elements (RVEs) of the real microstructure are generated and the mechanical properties of these RVEs are studied by the crystal plasticity finite element method. In this work, a new method is developed for extracting a reduced set of orientations from EBSD data containing a large number of orientations. This approach is based on the established integer approximation method and it minimizes its shortcomings. Furthermore, the L1 norm is applied as an error function; this is commonly used in texture analysis for quantitative assessment of the degree of approximation and can be used to control the convergence behavior. The method is tested on four experimental data sets to demonstrate its capabilities. This new method for the purposeful reduction of a set of orientations into equally weighted orientations is not only suitable for numerical simulation but also shows improvement in results in comparison with other available methods.




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GIWAXS-SIIRkit: Scattering Intensity, Indexing, and Refraction Calculation Toolkit for Grazing Incidence Wide Angle X-ray Scattering of Organic Materials

A software package for Grazing Incident Wide Angle X-ray Scattering (GIWAXS) geared toward weakly ordered materials, including: scattering intensity normalization/uncertainty, scattering pattern indexing, and refractive shift correction.




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A closer look at superionic phase transition in (NH4)4H2(SeO4)3: impedance spectroscopy under pressure

The proton-conducting material (NH4)4H2(SeO4)3 is examined to check whether its conductivity spectra are sensitive to subtle changes in the crystal structure and proton dynamics caused by external pressure. The AC conductivity was measured using impedance spectroscopy, in the frequency range from 100 Hz to 1 MHz, at temperatures 260 K < T < 400 K and pressures 0.1 MPa < p < 500 MPa. On the basis of the impedance spectra, carefully analyzed at different thermodynamic conditions, the p–T phase diagram of the crystal is constructed. It is found to be linear in the pressure range of the experiment, with the pressure coefficient value dTs/dp = −0.023 K MPa−1. The hydrostatic pressure effect on proton conductivity is also presented and discussed. Measurements of the electrical conductivity versus time were performed at a selected temperature T = 352.3 K and at pressures 0.1 MPa < p < 360 MPa. At fixed thermodynamic conditions (p = 302 MPa, T = 352.3 K), the sluggish solid–solid transformation from low conducting to superionic phase was induced. It is established that the kinetics of this transformation can be described by the Avrami model with an effective Avrami index value of about 4, which corresponds to the classical value associated with the homogeneous nucleation and three-dimensional growth of a new phase.




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A closer look at superionic phase transition in (NH4)4H2(SeO4)3: impedance spectroscopy under pressure

The proton-conducting crystal (NH4)4H2(SeO4)3 is examined to check whether its conductivity spectra and the phase transition to the superprotonic phase are sensitive to subtle changes in the crystal structure and proton dynamics caused by various thermodynamic conditions. It is established that the kinetics of this transformation can be described using the Avrami model with an effective Avrami index value associated with homogeneous nucleation and three-dimensional growth of a new phase.




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Video: Common birds in Washington, D.C. are helping Smithsonian scientists track intensity of the West Nile Virus

Scientists from the Smithsonian Migratory Bird Center at the National Zoo have taken blood samples from thousands of birds and mosquitoes in an effort to track the progress of the West Nile Virus in the eastern United States. Come along in this video as Smithsonian scientists net birds living in downtown Washington, D.C., extract small amounts of blood, and then release them back into the "wild."

The post Video: Common birds in Washington, D.C. are helping Smithsonian scientists track intensity of the West Nile Virus appeared first on Smithsonian Insider.




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Super sensitive telescope will detect “killer” asteroids and comets on collision course with Earth

This innovative facility will be at the front line of Earth defense by searching for "killer" asteroids and comets. It will map large portions of the sky nightly, making it an efficient sleuth for not just asteroids but also supernovae and other variable objects.

The post Super sensitive telescope will detect “killer” asteroids and comets on collision course with Earth appeared first on Smithsonian Insider.




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First transiting planets in a star cluster discovered

All stars begin their lives in groups. Most stars, including our Sun, are born in small, benign groups that quickly fall apart. Others form in […]

The post First transiting planets in a star cluster discovered appeared first on Smithsonian Insider.




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Scientists map pathway from narwhals’ sensitive tusk to brain

Chip a tooth and expose a nerve and the result can be a searing sensitivity to hot and cold. The hard outer layer of a […]

The post Scientists map pathway from narwhals’ sensitive tusk to brain appeared first on Smithsonian Insider.




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Transiting exoplanet with longest known year

Astronomers have discovered a transiting exoplanet with the longest known year. Kepler-421b circles its star once every 704 days. In comparison, Mars orbits our Sun […]

The post Transiting exoplanet with longest known year appeared first on Smithsonian Insider.




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A first: Ground-based telescope detects super-earth transit

Astronomers have measured the passing of a super-Earth in front of a bright, nearby Sun-like star using a ground-based telescope for the first time. The […]

The post A first: Ground-based telescope detects super-earth transit appeared first on Smithsonian Insider.




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CASSIOPEIA’S HIDDEN GEM: THE CLOSEST ROCKY, TRANSITING PLANET

Skygazers at northern latitudes are familiar with the W-shaped star pattern of Cassiopeia the Queen. This circumpolar constellation is visible year-round near the North Star. […]

The post CASSIOPEIA’S HIDDEN GEM: THE CLOSEST ROCKY, TRANSITING PLANET appeared first on Smithsonian Insider.




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Astronomers detect comets transiting distant stars

There are currently more than 3,500 confirmed known exoplanets thanks to the remarkable sensitivity of the Kepler spacecraft and to technological advances in space and […]

The post Astronomers detect comets transiting distant stars appeared first on Smithsonian Insider.



  • Science & Nature
  • Space
  • Spotlight
  • Center for Astrophysics | Harvard & Smithsonian

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En bloc TGN recruitment of Aspergillus TRAPPII reveals TRAPP maturation as unlikely to drive RAB1-to-RAB11 transition [RESEARCH ARTICLE]

M. Pinar and M. A. Penalva

TRAnsport Protein Particle (TRAPP) complexes regulate membrane traffic. TRAPPII and TRAPPIII share a core hetero-heptamer, also denoted TRAPPI. In fungi TRAPPIII and TRAPPII mediate GDP exchange on RAB1 and RAB11, respectively, regulating traffic across the Golgi, with TRAPPIII also activating RAB1 in autophagosomes. Our finding that Aspergillus nidulans TRAPPII can be assembled by addition of a TRAPPII-specific subcomplex onto core TRAPP prompted us to investigate the possibility that TRAPPI/TRAPPIII already residing in the Golgi matures into TRAPPII to determine a RAB1-to-RAB11 conversion as Golgi cisternae progress from early Golgi to TGN identity. By time-resolved microscopy we determine that the TRAPPII reporter Trs120/TRAPPC9 is recruited to existing TGN cisternae slightly before RAB11 arrives, and resides for~45 sec on them before cisternae tear off into RAB11 secretory carriers. Notably, the core TRAPP reporter Bet3/TRAPPC3 was not detectable in early Golgi cisternae, being instead recruited to TGN cisternae simultaneously with Trs120/TRAPPC9, indicating en bloc recruitment of TRAPPII to the Golgi and arguing strongly against the TRAPP maturation model.




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A new brain mitochondrial sodium-sensitive potassium channel: effect of sodium ions on respiratory chain activity [RESEARCH ARTICLE]

Javad Fahanik-babaei, Bahareh Rezaee, Maryam Nazari, Nihad Torabi, Reza Saghiri, Remy Sauve, and Afsaneh Eliassi

We have determined the electropharmacological properties of a new potassium channel from brain mitochondrial membrane by planar lipid bilayer method. Our results showed the presence of a channel with a conductance of 150 pS at potentials between 0 and –60 mV in 200 cis/50 trans mM KCl solutions.

The channel was voltage-independent, with an open probability value ~0.6 at different voltages. ATP did not affect current amplitude and Po at positive and negative voltages. Notably, adding iberiotoxin, charybdotoxin, lidocaine, and margatoxin had no effect on the channel behavior. Similarly, no changes were observed by decreasing the cis-pH to 6. Interestingly, the channel was inhibited by adding sodium in a dose dependent manner. Our results also indicated a significant increase in mitochondrial complex IV activity and membrane potential and decrease in complex I activity and mitochondrial ROS production in the presence of sodium ions.

We propose that inhibition of mitochondrial K+ transport by Na ions on K+ channel opening may be important for cell protection and ATP synthesis.




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BMP4 promotes the metastasis of gastric cancer by inducing epithelial-mesenchymal transition via Id1 [RESEARCH ARTICLE]

Ganlu Deng, Yihong Chen, Cao Guo, Ling Yin, Ying Han, Yiyi Li, Yaojie Fu, Changjing Cai, Hong Shen, and Shan Zeng

Epithelial-mesenchymal transition (EMT) is a crucial process for cancer cells to acquire metastatic potential, which primarily causes death in gastric cancer (GC) patients. Bone morphogenetic protein 4 (BMP4) is a member of the TGF-β family that plays an indispensable role in human cancers. However, little is known about its roles in GC metastasis. In this study, BMP4 was found to be frequently overexpressed in GC tissues and was correlated with patient's poor prognosis. BMP4 was upregulated in GC cell lines and promoted EMT and metastasis of GC cells both in vitro and in vivo, while knockdown of BMP4 significantly inhibited EMT and metastasis of GC cells. Meanwhile, the inhibitor of DNA binding 1 (Id1) was identified as a downstream target of BMP4 by PCR arrays and upregulated via Smad1/5/8 phosphorylation. Id1 knockdown attenuated BMP4-induced EMT and invasion in GC cells. Moreover, Id1 overexpression in BMP4 knockdown cells restored the promotion of EMT and cell invasion. In summary, BMP4 induced EMT to promote GC metastasis by upregulating Id1 expression. Antagonizing BMP4 may be a potential therapeutic strategy in GC metastasis.




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The many flavours of halogen bonds – message from experimental electron density and Raman spectroscopy

Experimental electron-density studies based on high-resolution diffraction experiments allow halogen bonds between heavy halogens to be classified. The topological properties of the electron density in Cl⋯Cl contacts vary smoothly as a function of the inter­action distance. The situation is less straightforward for halogen bonds between iodine and small electronegative nucleophiles, such as nitro­gen or oxygen, where the electron density in the bond critical point does not simply increase for shorter distances. The number of successful charge–density studies involving iodine is small, but at least individual examples for three cases have been observed. (a) Very short halogen bonds between electron-rich nucleophiles and heavy halogen atoms resemble three-centre–four-electron bonds, with a rather symmetric heavy halogen and without an appreciable σ hole. (b) For a narrow inter­mediate range of halogen bonds, the asymmetric electronic situation for the heavy halogen with a pronounced σ hole leads to rather low electron density in the (3,−1) critical point of the halogen bond; the properties of this bond critical point cannot fully describe the nature of the associated inter­action. (c) For longer and presumably weaker contacts, the electron density in the halogen bond critical point is only to a minor extent reduced by the presence of the σ hole and hence may be higher than in the aforementioned case. In addition to the electron density and its derived properties, the halogen–carbon bond distance opposite to the σ hole and the Raman frequency for the associated vibration emerge as alternative criteria to gauge the halogen-bond strength. We find exceptionally long C—I distances for tetra­fluoro­diiodo­benzene molecules in cocrystals with short halogen bonds and a significant red shift for their Raman vibrations.