Light induced electron spin resonance in a-Ge:H

We report the observation of light-induced electron spin resonance (LESR) in amorphous hydrogenated germanium. Two new lines with zero crossings near g=2.01 and g=2.03 were detected and ascribed to electrons and holes in the conduction- and valence-band-tail states, respectively. The ratio between the LESR spin densities of both lines is approximately one, suggesting the absence of spin pairing, charge defect creation, or LESR of dangling bonds. The growth and decay spectra exhibit dispersive behavior with a dispersion parameter ∼0.5. The decay spectrum is best fit assuming bimolecular recombination. The LESR spin density depends weakly on the photogeneration rate as a sublinear power law

Ecosystem services values at risk in the Atlantic coastal zone due to sea-level rise and socioeconomic development

Uncertainties about the future extent of sea-level rise (SLR) and socioeconomic development will determine the future of coastal ecosystem services and values. This study analyzes the joint impact of flooding and socioeconomic development on the future ecosystem services and values in the Atlantic coastal zone by 2100. To this end, flood probability maps (using the Uncertainty Bathtub Model; uBTM) and local ecosystem service value (ESV) estimates (using meta-analytic based global ecosystem service value functions for Provisioning, Regulating & maintenance, and Cultural ecosystem services across 12 biomes) are derived for a wide combination of Representative Concentration Pathway (RCP) and Shared Socioeconomic Pathways (SSP) scenarios to obtain future values of coastal ecosystem services (ES). Results show that the higher potential of ESV at risk is associated with RCP 8.5 and SSP5, i.e. the scenario associated with a narrative related to fossil-fueled development. For this scenario, by 2100, the coastal zone with the highest probable losses in Provisioning ESV is Europe (∼5.9 € billion/year), for Regulating & maintenance ESV this is North America (∼6.0 € billion/year) and for Cultural ESV this is South America (∼21.3 € billion/year). Countries facing highest relative risk of losing Provisioning ESV are the Netherlands (10.6 %), United States (7.4 %), and Mauritania (5.8 %). For Regulating & maintenance ESV, the top 3 countries impacted are Mauritania (17.6 %), the Netherlands (10.0 %) and Argentina (8.0 %). For Cultural ESV, the countries are Mexico (19.0 %), Denmark (18.1 %) and Sweden (15.6 %). Changes in ESV are exponentially related to flood risk and economic growth, such that small changes in flood or income lead to large changes in ESV. Unlike previous studies, the ESV functions used are dependent on time and local factors, such as population and income. Although population and income growth result in an increase in ESV, it also emphasizes the ecosystem service values at risk. Thus, sea-level rise and socioeconomic changes impact ecosystem services and values – directly affecting the well-being of the world population. The unequal distribution of coastal ecosystem service value losses across continents and countries highlighted in this work is important to identify what values are at risk and for whom. Adaptation measures and strategies can, in turn, be defined

The neutrophil-to-lymphocyte ratio : A narrative review

Peer reviewedPublisher PD

Determination of superconducting anisotropy from magnetization data on random powders as applied to LuNi2_2B2_2C, YNi2_2B2_2C and MgB2_2

The recently discovered intermetallic superconductor MgB2 appears to have a highly anisotopic upper critical field with Hc2(max)/Hc2(min} = \gamma > 5. In order to determine the temperature dependence of both Hc2(max) and Hc2(min) we propose a method of extracting the superconducting anisotropy from the magnetization M(H,T) of randomly oriented powder samples. The method is based on two features in dM/dT the onset of diamagnetism at Tc(max), that is commonly associated with Hc2, and a kink in dM/dT at a lower temperature Tc(min). Results for LuNi2B2C and YNi2B2C powders are in agreement with anisotropic Hc2 obtained from magneto-transport measurements on single crystals. Using this method on four different types of MgB2 powder samples we are able to determine Hc2(max)(T) and Hc2(min)(T) with \gamma \approx 6

Angular dependence of the bulk nucleation field Hc2 of aligned MgB2 crystallites

Studies on the new MgB2 superconductor, with a critical temperature Tc ~ 39 K, have evidenced its potential for applications although intense magnetic relaxation effects limit the critical current density, Jc, at high magnetic fields. This means that effective pinning centers must be added into the material microstructure, in order to halt dissipative flux movements. Concerning the basic microscopic mechanism to explain the superconductivity in MgB2, several experimental and theoretical works have pointed to the relevance of a phonon-mediated interaction, in the framework of the BCS theory. Questions have been raised about the relevant phonon modes, and the gap and Fermi surface anisotropies, in an effort to interpret spectroscopic and thermal data that give values between 2.4 and 4.5 for the gap energy ratio. Preliminary results on the anisotropy of Hc2 have shown a ratio, between the in-plane and perpendicular directions, around 1.7 for aligned MgB2 crystallites and 1.8 for epitaxial thin films. Here we show a study on the angular dependence of Hc2 pointing to a Fermi velocity anisotropy around 2.5. This anisotropy certainly implies the use of texturization techniques to optimize Jc in MgB2 wires and other polycrystalline components.Comment: 10 pages + 4 Figs.; Revised version accepted in Phys. Rev.

Magnetic Field Dependence Of The Curie-weiss Paramagnetism In Crv Alloys

The determination of the magnetic properties of antiferromagnetic Cr alloys requires careful consideration of the influence of the applied magnetic field. In this work we show that alloys of Cr-x at. % V present a Curie-Weiss paramagnetism above the Néel temperature, which is suppressed by a characteristic field HL. Samples with x=0.1, 0.2, and 0.4 were investigated through measurements of the magnetic susceptibility as a function of temperature, for different values of the magnetic field. A magnetic phase diagram showing the characteristic line HL vs x at. % V is proposed. © 1997 American Institute of Physics.818 PART 2A42094211Suzuki, T., Takaki, H., (1964) J. Phys. Soc. Jpn., 19, p. 1241Suzuki, T., (1966) J. Phys. Soc. Jpn., 21, p. 442Aidun, R., Arajs, S., Moyer, C.A., (1985) Phys. Status Solidi B, 128, p. 133Hill, P., Ali, N., De Oliviera, A.J.A., Ortiz, W.A., De Camargo, P.C., Fawcett, E., (1994) J. Phys. Condens. Matter., 6, p. 1761De Oliveira, A.J.A., Otriz, W.A., De Camargo, P.C., Galkin, V.Yu., (1996) J. Magn. Magn. Mater., 152, p. 86De Oliveira, A.J.A., De Lima, O.F., De Camargo, P.C., Ortiz, W.A., Fawcett, E., (1996) J. Phys. Condens. Matter., 8, pp. L403Benediktsson, G., Hedman, L., Aström, H.U., Rao, K.V., (1982) J. Phys. F, 12, p. 1439Booth, J.G., (1964) Phys. Status Solidi, 7 K, p. 157Bender, D., Müller, J., (1970) Phys. Kondens. Mater., 10, p. 342Buzdin, A.I., Men'shov, V.N., Tugushev, V.V., (1986) Zh. Eksp. Teor. Fiz., 91, p. 2204(1986) Sov. Phys. JETP, 64. , Engl. TranslTugushev, V.V., (1992) Modulated and Localized Structures of the Spin-Density Wave in Itinerant Antiferromagnets in Electronic Phase Transitions, p. 237. , edited by W. Hanke and Yu. Koapev Elsevier, AmsterdamDe Oliveira, A.J.A., De Lima, O.F., Ortiz, W.A., De Camargo, P.C., (1995) Solid State Commun., 96, p. 383De Oliveira, A.J.A., (1996), PhD. thesis, Universidade Federal de São Carlo

Rapid and reliable identification of intact Candida clinical isolates using MALDI-TOF ICMS

The significant increase in the frequency of candidiasis wide world has promoted the study and development of fast and reliable techniques aimed at the replacement of traditional methods used for identification and typing of Candida clinical isolates. Matrix Assisted Laser Desorption/Ionisation Time-Of-Flight lntact Cell Mass Spectrometry (MALDI-TOF ICMS) has been applied as current method for Candida identification in clinical laboratories. This method is reported as suitable fur routine identification in clinical laboratories and fast and reliable for identification of pathogenic yeasts. The main aim of this study was to compare MALDI-TOF ICMS performance with the classical phenotypic approach and molecular analyses to identify Candida species from clinical cases. Forty clinical Candida isolates preserved in URM Culture Collection fur I to 52 years were identified by morphological and biochemical analysis as Candida albicans (20), C. krusei (05), C. parapsilosis (11) and C. tropicalis (04). These identifications were compared with the discriminative capability of the new phenotypic approaches using MALDI-TOF ICMS. MALDI-TOF ICMS data demonstrated 15% discordance when compared with morphological and biochemical analyses. The discordant isolates were analysed by ITS sequencing which corroborated the MALDI-TOF ICMS identifications. Five Candida krusei isolates were renamed Issatchenkia orientalis by MALDI-TOF ICMS SARAMISTM database, which is their teleomorphic name. ln conclusion MALDI-TOF ICMS represents a rapid and reliable method of identifying Candida and also presents clear benefits when compared with the performance of existing daily routine methods applied at health centres and hospitals. Research leading to these results received funding from the European Community's Seventh Framework Program (FP7, 2007-2013), Research lnfrastructures Action, under grant agreement No. FP7-228310 (EMbaRC project). Thanks are also due to Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Brazil) for funding support.European Community's Seventh Fmmework Progmm (FP7, 2007-2013), Research lnfrastructures Action, under gmnt agreement No. FP7-228310 (EMbaRC project), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Brazil

Minimal model for aeolian sand dunes

We present a minimal model for the formation and migration of aeolian sand dunes. It combines a perturbative description of the turbulent wind velocity field above the dune with a continuum saltation model that allows for saturation transients in the sand flux. The latter are shown to provide the characteristic length scale. The model can explain the origin of important features of dunes, such as the formation of a slip face, the broken scale invariance, and the existence of a minimum dune size. It also predicts the longitudinal shape and aspect ratio of dunes and heaps, their migration velocity and shape relaxation dynamics. Although the minimal model employs non-local expressions for the wind shear stress as well as for the sand flux, it is simple enough to serve as a very efficient tool for analytical and numerical investigations and to open up the way to simulations of large scale desert topographies.Comment: 19 pages, 22 figure