Metal-insulator transition induced by 16O -18O oxygen isotope exchange in colossal negative magnetoresistance manganites

The effect of 16O-18O isotope exchange on the electric resistivity was studied for (La(1-y)Pr(y))0.7Ca0.3MnO3 ceramic samples. Depending on y, this mixed perovskite exhibited different types of low-temperature behavior ranging from ferromagnetic metal (FM) to charge ordered (CO) antiferromagnetic insulator. It was found that at y=0.75, the substitution of 16O by 18O results in the reversible transition from a FM to a CO insulator at zero magnetic field. The applied magnetic field (H >= 2 T) transformed the sample with 18O again to the metallic state and caused the increase in the FM transition temperature Tc of the 16O sample. As a result, the isotope shift of Tc at H = 2 T was as high as 63 K. Such unique sensitivity of the system to oxygen isotope exchange, giving rise even to the metal-insulator transition, is discussed in terms of the isotope dependence of the effective electron bandwidth which shifts the balance between the CO and FM phases.Comment: 5 pages (RevTeX), 2 eps figures included, to appear in J. Appl. Phys. 83, (1998

Lattice dynamics of coesite

The lattice dynamics of coesite has been studied by a combination of diffuse x-ray scattering, inelastic x-ray scattering and ab initio lattice dynamics calculations. The combined technique gives access to the full lattice dynamics in the harmonic description and thus eventually provides detailed information on the elastic properties, the stability and metastability of crystalline systems. The experimentally validated calculation was used for the investigation of the eigenvectors, mode character and their contribution to the density of vibrational states. High-symmetry sections of the reciprocal space distribution of diffuse scattering and inelastic x-ray scattering spectra as well as the density of vibrational states and the dispersion relation are reported and compared to the calculation. A critical point at the zone boundary is found to contribute strongly to the main peak of the low-energy part in the density of vibrational states. Comparison with the most abundant SiO2 polymorph - α-quartz - reveals similarities and distinct differences in the low-energy vibrational properties

InN thin film lattice dynamics by grazing incidence inelastic x-ray scattering

Achieving comprehensive information on thin film lattice dynamics so far has eluded well established spectroscopic techniques. We demonstrate here the novel application of grazing incidence inelastic x-ray scattering combined with ab initio calculations to determine the complete elastic stiffness tensor, the acoustic and low-energy optic phonon dispersion relations of thin wurtzite indium nitride films. Indium nitride is an especially relevant example, due to the technological interest for optoelectronic and solar cell applications in combination with other group III nitrides.J. S. acknowledges financial support from the Spanish Ministry of Science and Innovation by CICYT Grants No. MAT2010-2-129-C02-01 and No. ENE2008-04373, and by Generalitat de Catalunya Grant No. 2009SGR1251. F. J. M. is thankful for the financial support from CICYT projects No. CSD2007-00045 and No. MAT2010-21270-C04-04, and the "Programa de Incentivo a la Investigacion" of the Universidad Politecnica de Valencia through project No. UPV2010-0096. A. H. R. has been supported by CONACyT Mexico under projects No. TAMU-Conacyt and No. J-83247-F. We acknowledge the beam time granted by ESRF.Serrano, J.; Bosak, A.; Krisch, M.; Manjón Herrera, FJ.; Romero, AH.; Garro, N.; Wang, X.... (2011). InN thin film lattice dynamics by grazing incidence inelastic x-ray scattering. Physical Review Letters. 106(20):2055011-2055014. https://doi.org/10.1103/PhysRevLett.106.205501S2055011205501410620Wu, J., Walukiewicz, W., Yu, K. M., Ager, J. W., Haller, E. E., Lu, H., … Nanishi, Y. (2002). Unusual properties of the fundamental band gap of InN. Applied Physics Letters, 80(21), 3967-3969. doi:10.1063/1.1482786Davydov, V. Y., Klochikhin, A. A., Seisyan, R. P., Emtsev, V. V., Ivanov, S. V., Bechstedt, F., … Graul, J. (2002). Absorption and Emission of Hexagonal InN. Evidence of Narrow Fundamental Band Gap. physica status solidi (b), 229(3), r1-r3. doi:10.1002/1521-3951(200202)229:33.0.co;2-oJones, R. E., Yu, K. M., Li, S. X., Walukiewicz, W., Ager, J. W., Haller, E. E., … Schaff, W. J. (2006). Evidence forp-Type Doping of InN. Physical Review Letters, 96(12). doi:10.1103/physrevlett.96.125505Song, J.-H., Akiyama, T., & Freeman, A. J. (2008). Stabilization of Bulkp-Type and Surfacen-Type Carriers in Mg-Doped InN{0001}Films. Physical Review Letters, 101(18). doi:10.1103/physrevlett.101.186801Qian, Z. G., Shen, W. Z., Ogawa, H., & Guo, Q. X. (2004). Experimental studies of lattice dynamical properties in indium nitride. Journal of Physics: Condensed Matter, 16(12), R381-R414. doi:10.1088/0953-8984/16/12/r01Davydov, V. Y., Emtsev, V. V., Goncharuk, I. N., Smirnov, A. N., Petrikov, V. D., Mamutin, V. V., … Inushima, T. (1999). Experimental and theoretical studies of phonons in hexagonal InN. Applied Physics Letters, 75(21), 3297-3299. doi:10.1063/1.125330Majumdar, A. (1993). Microscale Heat Conduction in Dielectric Thin Films. Journal of Heat Transfer, 115(1), 7-16. doi:10.1115/1.2910673Xu, K., & Yoshikawa, A. (2003). Effects of film polarities on InN growth by molecular-beam epitaxy. Applied Physics Letters, 83(2), 251-253. doi:10.1063/1.1592309Gonze, X., Beuken, J.-M., Caracas, R., Detraux, F., Fuchs, M., Rignanese, G.-M., … Allan, D. C. (2002). First-principles computation of material properties: the ABINIT software project. Computational Materials Science, 25(3), 478-492. doi:10.1016/s0927-0256(02)00325-7Gonze, X. (2005). A brief introduction to the ABINIT software package. Zeitschrift für Kristallographie - Crystalline Materials, 220(5/6). doi:10.1524/zkri.220.5.558.65066Gonze, X., Amadon, B., Anglade, P.-M., Beuken, J.-M., Bottin, F., Boulanger, P., … Zwanziger, J. W. (2009). ABINIT: First-principles approach to material and nanosystem properties. Computer Physics Communications, 180(12), 2582-2615. doi:10.1016/j.cpc.2009.07.007Troullier, N., & Martins, J. L. (1991). Efficient pseudopotentials for plane-wave calculations. Physical Review B, 43(3), 1993-2006. doi:10.1103/physrevb.43.1993Hartwigsen, C., Goedecker, S., & Hutter, J. (1998). Relativistic separable dual-space Gaussian pseudopotentials from H to Rn. Physical Review B, 58(7), 3641-3662. doi:10.1103/physrevb.58.3641Kim, K., Lambrecht, W. R. L., & Segall, B. (1996). Elastic constants and related properties of tetrahedrally bonded BN, AlN, GaN, and InN. Physical Review B, 53(24), 16310-16326. doi:10.1103/physrevb.53.16310Sarasamak, K., Limpijumnong, S., & Lambrecht, W. R. L. (2010). Pressure-dependent elastic constants and sound velocities of wurtzite SiC, GaN, InN, ZnO, and CdSe, and their relation to the high-pressure phase transition: A first-principles study. Physical Review B, 82(3). doi:10.1103/physrevb.82.035201Wright, A. F. (1997). Elastic properties of zinc-blende and wurtzite AlN, GaN, and InN. Journal of Applied Physics, 82(6), 2833-2839. doi:10.1063/1.366114Łepkowski, S. P., Majewski, J. A., & Jurczak, G. (2005). Nonlinear elasticity in III-N compounds:Ab initiocalculations. Physical Review B, 72(24). doi:10.1103/physrevb.72.245201Bungaro, C., Rapcewicz, K., & Bernholc, J. (2000). Ab initiophonon dispersions of wurtzite AlN, GaN, and InN. Physical Review B, 61(10), 6720-6725. doi:10.1103/physrevb.61.6720Manjón, F. J., Marí, B., Serrano, J., & Romero, A. H. (2005). Silent Raman modes in zinc oxide and related nitrides. Journal of Applied Physics, 97(5), 053516. doi:10.1063/1.185622

Justified use of 5% amorolfine nail lacquer, in the treatment of toe onychomycosis

The article presents the description of three clinical cases of the successful treatment of toe onychomycosis and athlete’s foot of various etiologies using 5% amorolfine antifungal nail lacquer. The first case: a 31-year-old woman was diagnosed with white superficial onychomycosis of great toe caused by Trichophyton rubrum. The treatment with 5% amorolfine once a week for 6 months resulted in full recovery (both mycological and clinical). The second case: a 42-year-old woman developed onychomycosis after the application of decorative coating on her nails; onychomycosis was caused by Scopulariopsis brevicaulis. She was treated with itraconazole pulse therapy and 5% amorolfine lacquer. She fully recovered. The third case: a 65-year-old man with total onychomycosis of 10 toes developed the skin mycosis of the left foot and lower third of the leg. He was prescribed a therapy with sertaconazole cream and 5% amorolfine lacquer. The use of 5% amorolfine lacquer was continued to prevent from recurrent dermatomycosis. Thus, the above mentioned cases are a good example of the advantages of using 5% amorolfine lacquer in the treatment of most toe onychomycosis types caused by any pathogens (dermatophytes, yeasts or molds)

A eukaryote assemblage intercalated with Marinoan glacial deposits in South Australia

Video of digital X-ray tomographs (µCT) in longitudinal plane through cylinder of siltstone, maximum diameter seen (left to right when viewing movie) is 5.4m

ИСПОЛЬЗОВАНИЕ ПОКАЗАТЕЛЕЙ КОМПОНЕНТНОГО СОСТАВА ЭФИРНЫХ МАСЕЛ ДЛЯ ИДЕНТИФИКАЦИИ СОРТА

Essential oil crops and their essential oils are widely used in perfumery, cosmetic and food industries, traditional and folk medicine. The most important qualitative characteristic of essential oil crops is the content, component and enantiomeric composition of essential oils. Basil (Ocimum basilicum L. and Ocimum tenuiflorum L.) and hyssop (Hyssopus officinalis L.) belong to the promising essential oil crops for cultivation in the soil and climatic conditions of the Republic of Belarus. In the Belarusian State Agricultural Academy has created a number of varieties of essential oil crops, including 3 varieties of basil Ocimum basilicum L., 1 variety of basil Ocimum tenuiflorum L.) and 1 variety of hyssop Hyssopus officinalis L. The new varieties of basil and hyssop are characterized by a complex of morphometric, morphological and phenological sings.In the studies of the Belarusian State Agricultural Academy and the Belarusian State Technological University, the yield and content of essential oils of new zoned varieties of basil and common hyssop were analyzed. Using the method of enantioselective gas chromatography, the component and enantiomeric composition of essential oils of the studied varieties was determined. As a result of the research, it was determined that each variety has its own characteristic component and enantiomeric composition of essential oils. The studied varieties of basil and common hyssop contained up to 20 and 18 different components of essential oils respectively. The features of the component and enantiomeric composition of essential oils allow identifying the already created varieties of essential oil crops, as well as carrying out their selection to create varieties with certain properties. Эфиромасличные культуры и их эфирные масла широко используются в парфюмерии, косметической и пищевой промышленности, традиционной и народной медицине. Важнейшей качественной характеристикой эфирномасличных культур является содержание, компонентный и энантиомерный состав эфирных масел. Базилик обыкновенный, базилик тонкоцветный и иссоп лекарственный относятся к перспективным эфиромасличным культурам для возделывания в почвенно-климатических условиях Республики Беларусь. В Белорусской государственной сельскохозяйственной академии за последние годы создан ряд сортов малораспространенных эфиромасличных культур, в том числе 3 сорта базилика обыкновенного (Ocimum basilicum L.) Настена, Володар и Магия, 1 сорт базилика тонкоцветного (Ocimum tenuiflorum L.) Источник и 1 сорт иссопа лекарственного (Hyssopus officinalis L.) Завея, которые характеризуются комплексом морфометрических, морфологических и фенологических признаков. В исследованиях УО «Белорусская государственная сельскохозяйственная академия» и УО «Белорусский государственный технологический университет» изучены урожайность и содержание эфирных масел новых районированных сортов базилика обыкновенного, базилика тонкоцветного и иссопа лекарственного. Методом энантиоселективной газовой хроматографии определен компонентный и энантиомерный состав эфирных масел исследуемых сортов базилика и иссопа лекарственного. В результате исследований установлено, что каждый сорт имеет свой характерный компонентный и энантиомерный состав эфирных масел. У исследуемых сортов базилика обыкновенного и базилика тонкоцветного отмечено до 20 различных компонентов, у сортов иссопа лекарственного – до 18 различных компонентов эфирных масел. Особенности компонентного и энантиомерного состава эфирных масел позволяют идентифицировать уже созданные сорта эфирномасличных культур, а также проводить их селекцию для создания сортов с определенными свойствами

Pressure dependence of phonon modes across the tetragonal to collapsed tetragonal phase transition in CaFe2As2

The pressure dependence of a large number of phonon modes in CaFe2As2 with energies covering the full range of the phonon spectrum has been studied using inelastic x-ray and neutron scattering. The observed phonon frequency changes are in general rather small despite the sizable changes of the lattice parameters at the phase transition. This indicates that the bonding properties are not profoundly altered by the phase transition. The transverse acoustic phonons propagating along the c-direction are an exception because they stiffen very significantly in response to the large contraction of the c-axis. The lattice parameters are found to change significantly as a function of pressure before, during and after the first-order phase transition. However, the frequencies change nearly uniformly with the change in the lattice parameters due to pressure, with no regard specifically to the first-order phase transition. Density functional theory describes the frequencies in both the zero pressure and in the collapsed phase in a satisfactory way if based on the respective crystal structures

A FAIR based approach to data sharing in Europe

The European fusion research activities have, over recent decades, generated a vast and varied set of data. The volume and diversity of the data that need to be catalogued and annotated make the task of organising and making the data available within a broader environment very challenging. Nevertheless, there are strong scientific drivers as well as incentives and mandates from national research agencies suggesting that a more coherent approach to data referencing, dissemination and sharing would provide strong benefits to the fusion research community and beyond. Here, we discuss the technical requirements and developments needed to transition the current, and future, range of fusion research data to an open and Findable, Accessible, Interoperable, and Reusable data sharing structure guided by the principle \u27as open as possible, as closed as necessary\u27. Here we propose a set of recommendations and technical implementations needed to form a European data sharing environment for the fusion research programmes. Consistency with the emerging IMAS (ITER Integrated Modelling and Analysis Suite) infrastructure is considered to facilitate future deployments

Anti-cancer effects and mechanism of actions of aspirin analogues in the treatment of glioma cancer

INTRODUCTION: In the past 25 years only modest advancements in glioma treatment have been made, with patient prognosis and median survival time following diagnosis only increasing from 3 to 7 months. A substantial body of clinical and preclinical evidence has suggested a role for aspirin in the treatment of cancer with multiple mechanisms of action proposed including COX 2 inhibition, down regulation of EGFR expression, and NF-κB signaling affecting Bcl-2 expression. However, with serious side effects such as stroke and gastrointestinal bleeding, aspirin analogues with improved potency and side effect profiles are being developed. METHOD: Effects on cell viability following 24 hr incubation of four aspirin derivatives (PN508, 517, 526 and 529) were compared to cisplatin, aspirin and di-aspirin in four glioma cell lines (U87 MG, SVG P12, GOS – 3, and 1321N1), using the PrestoBlue assay, establishing IC50 and examining the time course of drug effects. RESULTS: All compounds were found to decrease cell viability in a concentration and time dependant manner. Significantly, the analogue PN517 (IC50 2mM) showed approximately a twofold increase in potency when compared to aspirin (3.7mM) and cisplatin (4.3mM) in U87 cells, with similar increased potency in SVG P12 cells. Other analogues demonstrated similar potency to aspirin and cisplatin. CONCLUSION: These results support the further development and characterization of novel NSAID derivatives for the treatment of glioma