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Coastal and marine ecosystems provide a host of services that are of vital importance to human well-being. We estimate the values of several provisioning, regulating, and recreational services using a combination of valuation methods. We find that the total value of these services in India was approximately ₹1.9 trillion (or US$0.11 trillion in purchase price parity [PPP] terms) in 2012–13, which constitutes about 2.4% of India’s net national product that year. Recreational services account for the largest share (45%), followed by regulating services (35%) and provisioning services (20%). These estimates do not include all the services provided by coastal and marine ecosystems; therefore, our estimates should be treated as a conservative underestimate of their total economic value. To the best of our knowledge, this is the first such attempt at the national level in India.

Thin films of the spin-crossover (SCO) molecule Fe{[Me2Pyrz]3BH}2 (Fe-pyrz) were sublimed on Si/SiO2 and quartz substrates, and their properties investigated by X-ray absorption and photoemission spectroscopies, optical absorption, atomic force microscopy, and superconducting quantum interference device. Contrary to the previously studied Fe(phen)2(NCS)2, the films are not smooth but granular. The thin films qualitatively retain the typical SCO properties of the powder sample (SCO, thermal hysteresis, soft X-ray induced excited spin-state trapping, and light induced excited spin-state trapping) but present intriguing variations even in micrometer-thick films: the transition temperature decreases when the thickness is decreased, and the hysteresis is affected. We explain this behavior in the light of recent studies focusing on the role of surface energy in the thermodynamics of the spin transition in nano-structures. In the high-spin state at room temperature, the films have a large optical gap (~5 eV), decreasing at thickness below 50 nm, possibly due to film morphology. [ABSTRACT FROM AUTHOR]

Reports that a series of Co/Ru/Co sandwiches has been prepared by ion beam sputtering on a glass substrate using different buffer layers in order to optimize the antiferromagnetic (AF) coupling strength and the giant magnetoresistance signal. Nonmagnetic buffers; Magnetic buffers; Comparison between Ru and Fe/Co/Cu buffers; Magnetotransport results; Atomic force microscopy.

Recent irradiation experiments on magnetic tunnel junctions (MTJ) using either light (C, O) or heavy (Ni) ion beams with energies in the range of 10 MeV/A are presented. The effects observed are small in amplitude but irreversible, and seem to depend upon the nature of the junctions.

We report the temperature dependent far-infrared spectrum of ultra-thin films of polyethylene oxide (PEO). Using the orientational specificity of infrared and far-infrared reflection–absorption spectroscopy and in-situ recrystallization, we find that during spin coating the PEO helices are initially in the plane of the film, but on crystallization reorient to be normal to the substrate. A splitting of the C–O torsional mode near 109 cm-1 is identified as arising from a distortion of the normal helical structure of PEO. Comparison with transmission spectra of cast films demonstrates the value of far-infrared reflection–absorption spectroscopy (FIRRAS) in the study of crystalline polymers in the far infrared. [ABSTRACT FROM AUTHOR]

A powerful technique for controlling the oxidation of ultrathin metallic layers is described. This technique consists of depositing the metallic layer to be oxidized on top of the soft magnetic layer of a bottom spin valve.

The present work reports on the inelastic, spin-dependent tunneling in magnetic junctions with AlOx barrier and Co50Fe50 ferromagnetic (FM) electrodes. The identification of the transport inelastic channels is possible through their distinctive temperature dependencies. For the observed temperature behavior of the magnetotransport properties of the junctions, two spin-dependent, inelastic mechanisms are proposed: assisted tunneling due to interfacial (a) magnons and (b) metallic phonons. Their relative contributions are closely linked to the microstructural properties of the FM metal/oxide interfaces, related to the plasma oxidation of the tunnel barrier and to thermal annealing. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A first experimental evidence of a significant tunneling magnetoresistance signal of about 5% at 300 K for a magnetic tunnel junction consisting of hard and soft magnetic layers separated by a 2 nm ZnS semiconducting barrier is reported. The samples have been grown by sputtering on Si(111) substrate at room temperature and have the following structure: Fe[sub 6 nm]Cu[sub 30 nm]CoFe[sub 1.8 nm]Ru[sub 0.8 nm]CoFe[sub 3 nm]ZnS[sub x]CoFe[sub 1 nm]Fe[sub 4 nm]Cu[sub 10 nm]Ru[sub 3 nm]. The hard magnetic bottom electrode consists of the artificial antiferromagnetic structure in which the rigidity is ensured by the antiferromagnetic exchange coupling between two FeCo layers through a Ru spacer layer. Barrier impedance scanning microscope (BISM) measurements reveal a good homogeneity of the barrier thickness. Electric transport measurements over square tunnel elements with lateral sizes between 3 and 100 μm, exhibit a typical tunnel current-voltage variations and tunnel res! istance of 2-3 kΩ μm2 with small variations which never exceed a factor of 2, which is in good agreement with the BISM results. This good reproducibility of the junctions is very promising for MRAMs and transistors applications. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this work we study properties of very thin insulating Al oxide films, used as barriers in magnetic tunnel junctions. For the small barrier thicknesses required for technological applications (∼10 Å), the presence of pinholes (direct contact between the ferromagnetic metals through the barrier), or oxidation inhomogeneities, are the major factors for vanishing of the tunnel magnetoresistance effect. We have produced and characterized very thin, pinhole-free Al oxide layers, incorporated in magnetic tunnel junctions. The transport properties of the different barriers were analyzed by barrier impedance scanning microscopy and were correlated with the magnetotransport properties of the patterned microsized junctions. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Magnetostatic interactions between the soft and the hard magnetic electrodes in magnetic tunnel junctions (MTJs) using artificial ferrimagnets (AFis) are analyzed. We attribute these interactions to the dispersion fields associated to magnetic inhomogeneities arising from domain walls due to local anisotropic ordering. These magnetostatic interactions can be controlled by adjusting the net magnetic moment of the AFi to optimize the magnetotransport response of the MTJ devices.© 2001 American Institute of Physics. Magnetostatic interactions between the soft and the hard magnetic electrodes in magnetic tunnel junctions (MTJs) using artificial ferrimagnets (AFis) are analyzed. We attribute these interactions to the dispersion fields associated to magnetic inhomogeneities arising from domain walls due to local anisotropic ordering. These magnetostatic interactions can be controlled by adjusting the net magnetic moment of the AFi to optimize the magnetotransport respons! e of the MTJ devices.© 2001 American Institute of Physics. Magnetostatic interactions between the soft and the hard magnetic electrodes in magnetic tunnel junctions (MTJs) using artificial ferrimagnets (AFis) are analyzed. We attribute these interactions to the dispersion fields associated to magnetic inhomogeneities arising from domain walls due to local anisotropic ordering. These magnetostatic interactions can be controlled by adjusting the net magnetic moment of the AFi to optimize the magnetotransport response of the MTJ devices.© 2001 American Institute of Physics. Magnetostatic interactions between the soft and the hard magnetic electrodes in magnetic tunnel junctions (MTJs) using artificial ferrimagnets (AFis) are analyzed. We attribute these interactions to the dispersion fields associated to magnetic inhomogeneities arising from domain walls due to local anisotropic ordering. These magnetostatic interactions can be controlled by adjusting the net magnetic! moment of the... [ABSTRACT FROM AUTHOR]

The impact of the micromagnetic configuration within the ferromagnetic layers on transport properties of hard/soft magnetic tunnel junctions is presented. An artificial ferrimagnetic (AFi) trilayer structure is used as a magnetically hard subsystem. Fluctuations in magnetization in the AFi affect the resistance of the tunnel junctions and are fully reflected in the shape and amplitude of the tunnel magnetoresistance signal. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Magnetic tunnel junctions have been fabricated, that use Co/Ru/Co and Co/Ru/CoFe artificial ferrimagnet (AFi) systems as hard magnetic electrodes. The ∼22% tunnel magnetoresistance signal obtained, at room temperature, for junctions with Co/Ru/Co was increased to ∼30% by taking advantage of the higher spin polarization of CoFe in contact with the barrier. Along with this improvement, a different reversal behavior for the AFi was obtained. Together with the enhanced thermal stability, up to 350 °C, of the junctions involving the Co/Ru/CoFe system potential use as magnetic sensors is discussed. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Zika virus became an epidemic in Brazil from early 2015, with the first cases of suspected microcephaly caused by Zika virus confirmed in the states of Rio Grande do Norte and Pernambuco. Since then, research has highlighted the need for further investigations to better understand the physiology, symptoms and prognoses in order to better follow up children with congenital Zika virus syndrome. The impact of Zika virus on the development of children with microcephaly is still unknown. Congenital Zika virus infection syndrome has its worst expression when infection occurs in the first trimester of pregnancy. It is also known that the pattern of neurological disorder varies depending on the age at which the mother was infected. However, changes in central functions are expected in most patients with microcephaly and significantly impar neuropsychomotor development, vision and hearing. So far, studies show controversial results. This investigation was an opportunity to learn about the influence of this neurological condition on the electrophysiological parameters and also made possible to compare the findings of the Early Language Milestone Scale with the results of the electrophysiological exams. This is a descriptive cross-sectional study developed in the Audiology Sector of the two brazilians Universities. The study included 20 children of both genders, composed by the research group, with microcephaly due to congenital Zika virus syndrome and by the control group, comparison group. In this research cortical auditory evoked potential exams were performed and the language development scale, aiming to apply electrophysiological and behavioral measures to assess hearing and language. Longer values were observed in the latency of the N1-P2 components and greater amplitude of the N1 component of the auditory cortical potential in the research group. The scale also showed significant impairment in the linguistic development of the children in the research group. The Smart tools EP software used for neural response analysis showed abnormalities in neurotransmission of frequency spectral characteristics in the auditory pathway in children with Zika microcephaly in frequency domain analysis. The software calculations showed much higher slope and total area values in this population, also suggesting failure in the automated perception control of acoustic changes related to the activity of the N1 component. Electrophysiological and behavioral measurements showed a pattern of atypical development of the auditory and linguistic system in children with suspected microcephaly by Zika virus. [ABSTRACT FROM AUTHOR]

Some precipitation reactions of superduplex stainless steels (SDSS) can improve hardness, yield, and ultimate strength, but with substantial decrease of corrosion resistance. One of these reactions is the spinodal decomposition of ferrite into Cr-rich fine precipitates (α′) and Cr-depleted matrix during low temperature aging. In this work, the effect of the α′ precipitation on the pitting corrosion resistance was investigated. The results showed that short duration heat treatments at 475 °C do not decrease the pitting corrosion resistance, but increase the hardness of UNS S32750 and S32760 SDSS. The limits of heat treatment duration for both steels were determined. [ABSTRACT FROM AUTHOR]

The paper presents a methodology that provides a solution for the one-day-ahead predispatch problem considering the evaluation and improvement of the voltage stability margin by optimising reactive-power injections by generators and synchronous condensers. Modal participation factors are used to define penalty indices for all generators, which are then added to the optimal power flow objective function. This identifies the most adequate reactive-power injection for each generator or synchronous condenser, to maximise voltage stability margins. The results obtained for the New England test system and a version of the Southwest Brazilian system show that the proposed methodology leads to significant improvement in voltage stability margin for all the critical time intervals of the day. The occurrence of contingencies in the system is also considered. One clear advantage of the proposed methodology is that the optimal (economical) solution for active power injection of generators is maintained unchanged, which means that there will be no impact on the energy targets of the hydroelectric plants, nor on total generation costs. Hence, the voltage stability margin is improved by simply managing reactive-power dispatch. [ABSTRACT FROM AUTHOR]

A new far-infrared spectrometer design is described that utilizes double polarization modulation. Based on the Martin–Puplett interferometer, this new design has high sensitivity in the region between 5 and 200 cm-1 and eliminates problems due to fluctuations in the source, interferometer drift, and reduced dynamic range in studies with small sample absorption. The new spectrometer allows, for the first time, the extension of reflection-absorption spectroscopy of ultrathin films and surface coatings into the far infrared. We present far infrared reflection-absorption data of ultrathin potassium iodide films and submicron thick polyethylene oxide films. Use of the spectrometer for far infrared dichroism studies of thin polymer films and dielectric crystals and polarization-dependent normal incidence reflectance measurements is also described. [ABSTRACT FROM AUTHOR]

New, active and stable catalysts competitive to Pt catalysts are necessary for fuel cell development. Here, we present few-layered graphene-supported Pd, revealing a performance superior to Pt/C and Pd/C ORR (positive half-wave potential shift E1/2 by 50 mV, approximately one order of magnitude higher area- and mass-normalized current densities, Iarea, Imass, after 2500 cycles). The catalyst preparation is easily scalable, simple, inexpensive and eco-friendly. [ABSTRACT FROM AUTHOR]

The dynamics of the soft x-ray induced excited spin state trapping (SOXIESST) effect of Fe(phen)2(NCS)2 (Fe-phen) powder have been investigated by x-ray absorption spectroscopy (XAS) using the total electron yield method, in a wide temperature range. The low-spin (LS) state is excited into the metastable high-spin (HS) state at a rate that depends on the intensity of the x-ray illumination it receives, and both the temperature and the intensity of the x-ray illumination will affect the maximum HS proportion that is reached. We find that the SOXIESST HS spin state transforms back to the LS state at a rate that is similar to that found for the light induced excited spin state trapping (LIESST) effect. We show that it is possible to use the SOXIESST effect in combination with the LIESST effect to investigate the influence of cooperative behavior on the dynamics of both effects. To investigate the impact of molecular cooperativity, we compare our results on Fe-phen with those obtained for Fe{[Me2Pyrz]3BH}2 (Fe-pyrz) powder, which exhibits a similar thermal transition temperature but with a hysteresis. We find that, while the time constant of the dynamic is identical for both molecules, the SOXIESST effect is less efficient at exciting the HS state in Fe-pyrz than in Fe-phen. [ABSTRACT FROM AUTHOR]

The quality of a SrTiO3 tunnel barrier deposited by pulsed laser deposition on SrTiO3 (001)∥Sr2FeMoO6 is investigated. Epitaxy and two-dimensional growth are obtained and the root-mean-square roughness is 0.3 nm. The distribution of the local current measured by conductive atomic force microscopy indicates that hot spots are almost absent. The standard deviation of the barrier thickness distribution is lower than 0.05 nm. Current-voltage characteristics of patterned magnetic tunnel junctions provide evidence of the high quality of the barrier. The electrical properties of the SrTiO3 barrier are at least as good as the ones obtained by sputtering or e-beam evaporation. [ABSTRACT FROM AUTHOR]

Epitaxially grown magnetic tunnel junctions MgO(100)/Fe/MgO/Fe/Co/Pd have been elaborated by molecular beam epitaxy, with insulating layer thickness down to 0.8 nm. The continuity of this layer was checked at different spatial scales by means of morphological (high resolution transmission electronic microscopy), electric (local impedance), and magnetic (magnetoresistance and hysteresis loop) measurements. These junctions show a low resistance (4 kΩ µm²), tunnel magnetoresistance up to 17%, and a very small interlayer magnetic coupling. [ABSTRACT FROM AUTHOR]

Quantum coherent transport in double barrier tunnel junctions has been exploited for building micrometric-size semiconductor-free diodes. At room temperature, we observe strongly asymmetric current-voltage characteristics with an asymmetry ratio increasing with the bias voltage, reaching a maximum of 20 at 1 V. Our experimental data can be perfectly explained using a theoretical model involving resonance-assisted tunneling. The coherent/resonant tunneling regime is achieved using metallic 3 nm diameter monodisperse Cu clusters, sandwiched between two Al[sub 2]O[sub 3] barriers. © 2001 American Institute of Physics. [DOI: 10.1063/1.1426685]. [ABSTRACT FROM AUTHOR]

In this work we study phenomena related to the plasma oxidation of thin metallic Al layers, to be used as insulating barriers in magnetic tunnel junctions. We investigate by barrier impedance scanning microscopy how the barrier’s over oxidation influences the local transport characteristics of the oxide layers and the results are correlated with the magnetotransport properties of patterned microsized as-deposited and annealed junctions. Interestingly, the oxygen reservoir existing at the ferromagnetic metal, degenerating the tunnel device, can be utilized for the improvement of the junction’s magnetotransport properties by means of thermal annealing processing. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We report modifications for a recently described double polarization modulation far infrared spectrometer. By changing the input polarizer switching dynamics, we further reduce spectral noise caused by instability of the plasma in the mercury arc source. [ABSTRACT FROM AUTHOR]