Search

Silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) are key devices for next-generation power electronics. However, accurate determination of device parameters from 3-terminal characteristics is hampered by the presence of interface traps. Here we present a method that, in contrast to previous evaluation schemes, explicitly considers those defects. A well-tractable parametrization of the SiC/SiO2-specific interface trap spectrum is introduced that reflects the body of known data. With this ingredient, we develop an analysis that targets for an accurate determination of device parameters from simple 3-terminal characteristics. For its validation, we investigate MOSFETs with significantly different defect densities. The resulting parameters – charge carrier density, mobility and threshold voltage – are in excellent agreement with Hall effect investigations on the very same devices, avoiding systematic errors inherent to conventional evaluation techniques. With this adapted scheme, 4H-SiC power MOSFETs, even packaged, can be meaningfully characterized, speeding up innovation cycles in energy-saving power electronics.

The Amazon rain forest experiences the combined pressures from human-made deforestation and progressing climate change, causing severe and potentially disruptive perturbations of the ecosystem's integrity and stability. To intensify research on critical aspects of Amazonian biosphere–atmosphere exchange, the Amazon Tall Tower Observatory (ATTO) has been established in the central Amazon Basin. Here we present a multi-year analysis of backward trajectories to derive an effective footprint region of the observatory, which spans large parts of the particularly vulnerable eastern basin. Further, we characterize geospatial properties of the footprint regions, such as climatic conditions, distribution of ecoregions, land cover categories, deforestation dynamics, agricultural expansion, fire regimes, infrastructural development, protected areas, and future deforestation scenarios. This study is meant to be a resource and reference work, helping to embed the ATTO observations into the larger context of human-caused transformations of Amazonia. We conclude that the chances to observe an unperturbed rain forest–atmosphere exchange at the ATTO site will likely decrease in the future, whereas the atmospheric signals from human-made and climate-change-related forest perturbations will increase in frequency and intensity.

Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of the mean monthly space used by sharks falls under the footprint of pelagic longline fisheries. Space-use hotspots of commercially valuable sharks and of internationally protected species had the highest overlap with longlines (up to 76% and 64%, respectively), and were also associated with significant increases in fishing effort. We conclude that pelagic sharks have limited spatial refuge from current levels of fishing effort in marine areas beyond national jurisdictions (the high seas). Our results demonstrate an urgent need for conservation and management measures at high-seas hotspots of shark space use, and highlight the potential of simultaneous satellite surveillance of megafauna and fishers as a tool for near-real-time, dynamic management., Data analysis was funded in part by the Marine Biological Association (MBA) and the UK Natural Environment Research Council (NERC) (NE/R00997X/1) (to D.W.S.) with additional research support from the Save Our Seas Foundation and the NERC Oceans 2025 Strategic Research Programme, in which D.W.S. was a principal investigator. D.W.S. was supported by an MBA Senior Research Fellowship, N.Q. by European Regional Development Fund (FEDER) via the Programa Operacional Competitividade e Internacionalização (COMPETE), National Funds via Fundação para a Ciência e a Tecnologia (FCT) under PTDC/MAR/100345/2008 and COMPETE FCOMP-01-0124-FEDER-010580 (to N.Q. and D.W.S.), and Norte Portugal Regional Operational Programme (NORTE 2020) under the PORTUGAL 2020 Partnership Agreement through the European Regional Development Fund (ERDF) in project MarInfo (NORTE-01-0145-FEDER-000031). Additional support was provided by an FCT Investigator Fellowship IF/01611/2013 (N.Q.), FCT Doctoral Fellowship PD/BD/52603/2014 (M.V.), PTDC/MAR-BIO/4458/2012, Xunta de Galicia - Isabel Barreto Program 2009-2012 (G.M.), Australian Research Council (ARC) grant DE170100841 and operational funds from the Australian Institute for Marine Science (AIMS) (both to A.M.M.S.).

The first measurement of the Upsilon(1S) elliptic flow coefficient (v(2)) is performed at forward rapidity (2.5 < y < 4) in Pb-Pb collisions at root s(NN) = 5.02 TeV with the ALICE detector at the LHC. The results are obtained with the scalar product method and are reported as a function of transverse momentum (pT) up to 15 GeV/c in the 5%-60% centrality interval. The measured Upsilon(1S)v(2) is consistent with 0 and with the small positive values predicted by transport models within uncertainties. The v(2) coefficient in 2 < p(T) < 15 GeV=c is lower than that of inclusive J/psi mesons in the same p(T) interval by 2.6 standard deviations. These results, combined with earlier suppression measurements, are in agreement with a scenario in which the Upsilon(1S) production in Pb-Pb collisions at LHC energies is dominated by dissociation limited to the early stage of the collision, whereas in the J/psi case there is substantial experimental evidence of an additional regeneration component.

We demonstrate that currents induced in graphene by ultrashort laser pulses are sensitive to the exact shape of the electric-field waveform. By increasing the field strength, we found a transition of the light–matter interaction from the weak-field to the strong-field regime at around 2 V/nm, where intraband dynamics influence interband transitions. In this strong-field regime, the light-matter interaction can be described by the wavenumber trajectories of electrons in the reciprocal space. For linearly polarized light the electron dynamics are governed by repeated sub-optical-cycle Landau-Zener transitions between the valence- and conduction band, resulting in Landau-Zener-Stuckelberg interference, whereas for circular polarized light this interference is supressed.

We present an efficient Schottky-diode detection scheme for Terahertz (THz) radiation, implemented on the material system epitaxial graphene on silicon carbide (SiC). It employs SiC as semiconductor and graphene as metal, with an epitaxially defined interface. For first prototypes, we report on broadband operation up to 580 GHz, limited only by the RC circuitry, with a responsivity of 1.1 A/W. Remarkably, the voltage dependence of the THz responsivity displays no deviations from DC responsivity, which encourages using this transparent device for exploring the high frequency limits of Schottky rectification in the optical regime. The performance of the detector is demonstrated by resolving sharp spectroscopic features of ethanol and acetone in a THz transmission experiment.

A search for mixing between active neutrinos and light sterile neutrinos has been performed by looking for muon neutrino disappearance in two detectors at baselines of 1.04 and 735 km, using a combined MINOS and MINOS+ exposure of 16.36×1020 protons on target. A simultaneous fit to the charged-current muon neutrino and neutral-current neutrino energy spectra in the two detectors yields no evidence for sterile neutrino mixing using a 3+1 model. The most stringent limit to date is set on the mixing parameter sin2θ24 for most values of the sterile neutrino mass splitting Δm412>10-4 eV2. © 2019 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/" Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP 3 .

Antimicrobial resistance is a serious public health problem and Salmonella spp. is highly resistant to antimicrobial agents. Biofilms are important in the food industry due to their formation on products, utensils, and surfaces and the difficulty in their removal. The objective of this study was to assess extended spectrum beta-lactamase (ESBL) production, antimicrobial resistance, and biofilm production of Salmonella isolated from poultry slaughterhouses. Antimicrobial susceptibility was assessed by the disk diffusion assay and ESBL by double diffusion disk assay using the beta-lactamase inhibitor (amoxicillin+clavulanate). The antimicrobials tested were: ampicillin, amoxicillin+clavulanate, aztreonam, ceftazidime, cefotaxime, chloramphenicol, gentamicin, enrofloxacin, sulfonamide, and tetracycline. Serovars Infantis, Panama, and Tennessee were found to produce ESBL. All serovars were sensitive to tetracycline, and S. Brandenburg was sensitive to all drugs tested. Serovars Panama, Anatum, Infantis, and Schwarzengrund were moderate biofilm producers at 3 oC and 9 oC±1 oC, respectively, showing possible adaptation of these serovars to these temperatures. Antimicrobials should be used with caution because of the levels of resistance observed and because of ESBL production, and hygiene and sanitary measures should be enhanced to minimize the adhesion of biofilm-forming Salmonella serovars at refrigeration temperatures.

AxesSim has developed an electromagnetic simulation tool named TETA, which is optimized for harnessing several GPUs in parallel. It is based on the Discontinuous Galerkin method in the Time Domain (DGTD). This method allows to handle meshes of complex geometries and can model designs with high precision such as a full human body with its organs, clothes and surrounding environment. The targeted architecture is a CRAY XC50 (PizDaint) which is a supercomputer with Intel Broadwell CPUs and NVidia P100 GPUs. Both CPU and GPU are addressed via the OpenCL library. MPI is used for communication between accelerators and hosts.

Optogenetic technologies have been the subject of great excitement within the scientific community for their ability to demystify complex neurophysiological pathways in the central (CNS) and peripheral nervous systems (PNS). The excitement surrounding optogenetics has also extended to the clinic with a trial for ChR2 in the treatment of retinitis pigmentosa currently underway and additional trials anticipated for the near future. In this work, we identify the cause of loss-of-expression in response to transdermal illumination of an optogenetically active peroneal nerve following an anterior compartment (AC) injection of AAV6-hSyn-ChR2(H134R) with and without a fluorescent reporter. Using Sprague Dawley Rag2−/− rats and appropriate controls, we discover optogenetic loss-of-expression is chiefly elicited by ChR2-mediated immunogenicity in the spinal cord, resulting in both CNS motor neuron death and ipsilateral muscle atrophy in both low and high Adeno-Associated Virus (AAV) dosages. We further employ pharmacological immunosuppression using a slow-release tacrolimus pellet to demonstrate sustained transdermal optogenetic expression up to 12 weeks. These results suggest that all dosages of AAV-mediated optogenetic expression within the PNS may be unsafe. Clinical optogenetics for both PNS and CNS applications should take extreme caution when employing opsins to treat disease and may require concurrent immunosuppression. Future work in optogenetics should focus on designing opsins with lesser immunogenicity.

Technical components are usually well optimized. However, simply combining these optimized components in a technical system does not necessarily lead to optimal systems. Therefore, focusing on a system perspective reveals new potential for optimization. In this context, we examine thermofluid systems which can be interpreted as fluid systems with superimposed heat transfer. The structure of such systems can be abstracted as a graph – more specifically, a flow network. We translate the underlying optimization problem into a mixed-integer linear program which is designed to obey the physical laws of heat transfer. Typically, fluid systems can be considered as quasi-stationary systems since their dynamic effects are usually negligible. However, for thermofluid systems this assumption does not hold because time-dependency is an issue as storage tanks for heated fluid gain importance. In order to handle the dynamic effects induced by the storage tanks, we further introduce a continuous-time representation based on a global event-based formulation.

Objective Obesity during pregnancy impedes fetal iron endowment. In adults, both iron depletion and hypoxia stimulate erythropoietin (Epo) production, while hepcidin, the primary iron regulator, is inhibited by Epo and stimulated by obesity. To understand this relationship in fetuses, we investigated obesity, inflammation, and fetal iron status on fetal Epo and hepcidin levels. Study Design Epo, hepcidin, C-reactive protein (CRP), and ferritin levels were measured in 201 newborns of 35 to 40 weeks' gestation with historical risk factors for a low fetal iron endowment, including half with maternal obesity. Results Epo was unrelated to fetal size, but Epo was directly related to maternal body mass index (BMI; kg/m2) (p Conclusion Although some of the fetal responses involving Epo were similar to adults, we did not find a hepcidin–Epo relationship like that of adults, where fetal liver is the site of both hepcidin and Epo production.

Lead halide perovskites are used in thin-film solar cells, which owe their high efficiency to the long lifetimes of photocarriers. Various calculations find that a dynamical Rashba effect could significantly contribute to these long lifetimes. This effect is predicted to cause a spin splitting of the electronic bands of inversion-symmetric crystalline materials at finite temperatures, resulting in a slightly indirect band gap. Direct experimental evidence of the existence or the strength of the spin splitting is lacking. Here, we resonantly excite photocurrents in single crystalline ( C H 3 N H 3 ) P b I 3 with circularly polarized light to clarify the existence of spin splittings in the band structure. We observe a circular photogalvanic effect, i.e., the photocurrent depends on the light helicity, in both orthorhombic and tetragonal ( C H 3 N H 3 ) P b I 3 . At room temperature, the effect peaks for excitation photon energies Δ E = 110 meV below the direct optical band gap. Temperature-dependent measurements reveal a sign change of the effect at the orthorhombic–tetragonal phase transition, indicating different microscopic origins in the two phases. Within the tetragonal phase, both Δ E and the amplitude of the circular photogalvanic effect increase with temperature. Our findings support a dynamical Rashba effect in this phase, i.e., a spin splitting caused by thermally induced structural fluctuations which break inversion symmetry.

In the face of accelerating ecological change to the world's oceans, seabirds are some of the best bio-indicators of marine ecosystem function. However, unravelling ecological changes that pre-date modern monitoring programmes remains challenging. Using stable isotope analysis of feathers and regurgitants collected from sooty terns (Onychoprion fuscatus) nesting at a major Atlantic colony, we reconstructed a long-term dietary time series from 1890 to the present day and show that a significant dietary shift occurred during the second half of the twentieth century coinciding with an apparent population collapse of approximately 84%. After correcting for the "Suess Effect," δ13 C in feathers declined by ~1.5‰ and δ15 N by ~2‰ between the 1890s and the present day, indicating that birds changed their diets markedly over the period of population decline. Isotopic niches were equally wide before and after the population collapse but isotopic mixing models suggest that birds have grown ever more reliant on nutrient-poor squid and invertebrates as teleost fish have declined in availability. Given that sooty terns rely heavily on associations with sub-surface predators such as tuna to catch fish prey, the rapid expansion of industrialized fisheries for these species over the same period seems a plausible mechanism. Our results suggest that changes to marine ecosystems over the past 60 years have had a dramatic impact on the ecology of the most abundant seabird of tropical oceans, and highlight the potentially pervasive consequences of large predatory fish depletion on marine ecosystem function.

Modern electro-optical systems often include several channels for imaging at different bands. These systems are capped with a window assembly in which the optical windows are cemented to a frame using dedicated adhesives intended to seal the system’s internal optics from the outside environment. Such window assemblies may include several optical windows made of different materials, depending on the necessary spectral bands, and are usually very expensive. Occasionally, these windows, become damaged due to exposure to severe environments, and require replacement. In such a case, there is a need for a detachment process to remove and replace only the defective part without damaging the rest of the windows or the metal frame. In this work, we have developed a dedicated tool which enables cost-effective and selective detachment of only the defective parts without any damage to the rest of the window assembly. The detachment process is based on a 3-axis hotwire automated system that was inspired by the foam cutting industry. An electrical current is passed through a hotwire which is then used to selectively decompose the adhesive along the bond line. Parameters such as wire voltage, wire tension, and velocity were selected to yield the best performance, namely, quick and safe removal of the part. The flexibility of the system’s design allows for detaching windows of different geometries, materials, and sizes.

Objetivo: O artigo descreve o percurso metodológico utilizado na construção de um levantamento de dados como pesquisa exploratória com amostragem sistemática para se conhecer a natureza das ações judiciais (contra) em que figuram como réu, os governos municipais que demandam produtos e serviços para a Saúde. Metodologia: O projeto foi planejado para ser desenvolvido no âmbito do Programa de Apoio ao Desenvolvimento Institucional do Sistema Único de Saúde como parceria entre a Fundação Oswaldo Cruz de Brasília, o Ministério da Saúde e o Hospital do Coração em São Paulo e cobrir todo o território brasileiro como um esforço para dimensionar um quadro nacional da Judicialização das Políticas Públicas de Saúde nos municípios e subsidiar a formação de um Observatório Nacional da Judicialização da Saúde. Resultados: Os resultados devem contribuir para um melhor controle das demandas judiciais tanto por parte do Ministério da Saúde como por parte dos Tribunais de Justiça por meio do conhecimento das demandas em si e dos caminhos percorridos pelos autores das ações para a formação dos processos. Conclusão: O projeto cobre uma lacuna de conhecimento importante sobre a natureza das demandas judiciais e políticas públicas de saúde e propõe o exercício da continuidade do monitoramento das demandas judiciais, que crescem dia após dia e se especializam em diversos aspectos.

Magnetostrictive composites are of considerable interest for real-time remote force sensing and structural health monitoring. In this paper, we introduce a new procedure for modeling the magnetic field induced by an external load applied on an epoxy-based composite material filled with Terfenol-D particles. This model is based on an assumed sequence of physical processes that occur at the microscopic scale, and it includes both domain switching and magnetization rotation. The modeling procedure is demonstrated on a problem relevant for load sensing applications in which the magnetostrictive composite is subjected to a uniaxial compression. Comparison of the calculated and experimental results strengthens the validity of the assumed sequence of physical processes and provides valuable insights important for application developments.

The 5th Generation of mobile networks (5G) is expected to be rolled out by 2020. New and revolutionary applications are already being envisioned, real-time control of machines, the Tactile Internet for wireless, Industry 4.0, the Internet of Things and self-driving cars, among others. To make this possible important enhancements and improvements in today's existing telecommunication technologies form an end-to-end perspective are required. Early testing and fast prototyping of new approaches and solutions will help to shape the evolving technologies. One of the technical enablers for 5G are two concepts based on the softwarisation and virtualisation of the core network, known as Software Defined Networking (SDN) and Network Function Virtualisation, NFV. Fraunhofer FOKUS has set up the Open5GCore testing environment to start shaping, together with its partners, the nascent 5G technologies by addressing these topics together with other relevant technological developments. After a short motivation, the architecture of the open5GCore is presented, followed by a functional description of supported features.

In this paper we study the existence of weak solutions to a steady system describing the motion of micropolar electrorheological fluids. The constitutive relations for the stress tensors belong to the class of generalized Newtonian fluids. The analysis of the problem leads naturally to weighted Sobolev spaces. The emphasis of the paper is devoted to the study of the degenerate problem. Using the Lipschitz truncation and the L ∞ -truncation we derive various lower bounds, depending also on the electric field, ensuring the existence of solutions.

Contrary to common belief, bilayer graphene is not defect-free: the abundance of partial dislocations leads to a mosaic-like network structure. As a result, as now shown, the magnetoresistance of bilayer graphene depends linearly, rather than quadratically, on the external magnetic field. The magnetoresistance of conductors usually has a quadratic dependence on magnetic field1, however, examples exist of non-saturating linear behaviour in diverse materials2,3,4,5,6. Assigning a specific microscopic mechanism to this unusual phenomenon is obscured by the co-occurrence and interplay of doping, mobility fluctuations and a polycrystalline structure7,8. Bilayer graphene has virtually no doping fluctuations, yet provides a built-in mosaic tiling due to the dense network of partial dislocations9,10. We present magnetotransport measurements of epitaxial bilayer graphene that exhibits a strong and reproducible linear magnetoresistance that persists to B = 62 T at and above room temperature, decorated by quantum interference effects at low temperatures. Partial dislocations thus have a profound impact on the transport properties in bilayer graphene, a system that is frequently assumed to be dislocation-free. It further provides a clear and tractable model system for studying the unusual properties of mosaic conductors.

The electrical properties of the interface between quasi free standing bilayer graphene (QFBLG) and SiC(0001) have been investigated by nanoscale resolution current measurements using conductive atomic force microscopy (CAFM). I-V analyses were carried out on Au-capped QFBLG contacts with different sizes (from 200 down to 0.5 μm) fabricated on SiC samples with different miscut angles (from on-axis to 3.5° off-axis). The extracted QFBLG/SiC Schottky barrier height (SBH) was found to depend on the contact size. SBH values ∼0.9-1 eV were obtained for large contacts, whereas a gradual increase was observed below a critical (micrometer scale) contact size (depending on the SiC miscut angle) up to values approaching ∼1.5 eV. Nanoscale resolution current mapping on bare QFLBG contacts revealed that SiC step edges and facets represent preferential current paths causing the effective SBH lowering for larger contacts. The reduced barrier height in these regions can be explained in terms of a reduced doping of QFBLG from SiC substrate at (11-20) step edges with respect to the p-type doping on the (0001) terraces.

We have investigated the electrical properties of germanium-implanted n-type 4H-SiC epitaxial layers. Deep level transient spectroscopy (DLTS) was employed in order to study the influence of germanium ions on implantation-induced point defects. In particular, we observe a decrease of the concentration of Z1/2defect with increasing dose of implanted germanium.

Epitaxial graphene on silicon carbide (SiC) can easily be grown by thermal decomposition. A well-defined epitaxial interface between graphene and substrate is formed, especially when the silicon face of hexagonal polytypes is employed. It is found that as-grown monolayer graphene with interfacial buffer layer provides perfectly ohmic contacts to n-type SiC – even to low-doped epitaxial layers without contact implantation. Contact resistances to highly doped samples are competitive with conventional annealed nickel (Ni) contacts; a direct comparison of Ni and graphene contacts on 4H-SiC resulted in an one order of magnitude reduction of the contact resistance in the case of graphene contacts. On highly doped 6H-SiC, a specific contact resistance as low asρC= 5.9·10-6Ωcm2was found. This further improvement compared to 4H-SiC is assigned to better matching of work functions at the Schottky-like interface.

Objective Patients with suspected mesial temporal lobe (MTL) epilepsy typically undergo inpatient video–electroencephalography (EEG) monitoring with scalp and/or intracranial electrodes for 1 to 2 weeks to localize and lateralize the seizure focus or foci. Chronic ambulatory electrocorticography (ECoG) in patients with MTL epilepsy may provide additional information about seizure lateralization. This analysis describes data obtained from chronic ambulatory ECoG in patients with suspected bilateral MTL epilepsy in order to assess the time required to determine the seizure lateralization and whether this information could influence treatment decisions. Methods Ambulatory ECoG was reviewed in patients with suspected bilateral MTL epilepsy who were among a larger cohort with intractable epilepsy participating in a randomized controlled trial of responsive neurostimulation. Subjects were implanted with bilateral MTL leads and a cranially implanted neurostimulator programmed to detect abnormal interictal and ictal ECoG activity. ECoG data stored by the neurostimulator were reviewed to determine the lateralization of electrographic seizures and the interval of time until independent bilateral MTL electrographic seizures were recorded. Results Eighty-two subjects were implanted with bilateral MTL leads and followed for 4.7 years on average (median 4.9 years). Independent bilateral MTL electrographic seizures were recorded in 84%. The average time to record bilateral electrographic seizures in the ambulatory setting was 41.6 days (median 13 days, range 0–376 days). Sixteen percent had only unilateral electrographic seizures after an average of 4.6 years of recording. Significance About one third of the subjects implanted with bilateral MTL electrodes required >1 month of chronic ambulatory ECoG before the first contralateral MTL electrographic seizure was recorded. Some patients with suspected bilateral MTL seizures had only unilateral electrographic seizures. Chronic ambulatory ECoG in patients with suspected bilateral MTL seizures provides data in a naturalistic setting, may complement data from inpatient video-EEG monitoring, and can contribute to treatment decisions.

We demonstrate that terminal alkynyl moieties represent powerful functional groups for driving thermally stable, on-surface supramolecular structure formation on a reactive substrate. Through a combination of scanning tunneling microscopy, X-ray photoelectron spectroscopy, near-edge X-ray absorption-fine-structure spectroscopy and density functional theory calculations, we investigate the molecule–surface interaction and self-assembly of two prototypical hydrocarbon species on Cu(111). For 1,3,5-tris(4-ethynylphenyl)benzene (Ext-TEB) adsorption at low temperature (200 K) results in nonassembling, conformationally adapted intact species. Deprotonation of the terminal alkyne moieties, taking place at temperatures ranging from 300 to 350 K, triggers the formation of room-temperature stable, close-packed supramolecular islands. Through DFT calculations, the stabilizing interaction is identified as a trifurcated ionic C–H···π–δ hydrogen bonding between the π-system of the ionic alkynyl groups and methine moiet...

Many animals reproduce in large aggregations, which can vary in size from dozens to millions of individuals across species, time and space. The size of breeding colonies is a complex trade-off between multiple costs and benefits to an individual’s fitness, but the mechanisms by which colony size affects fitness are still poorly understood. One important cost of breeding in a large colony is the spatial constraint in resource use due to the need to regularly return to a central location. Large aggregations, like seabird breeding colonies, may therefore deplete food resources near the colony, forcing individuals to travel farther to find food, which may ultimately limit their reproductive output and population size. This hypothesis, proposed in 1963 by Ashmole for tropical oceanic islands, has so far not been tested at tropical seabird colonies, where food availability is less predictable than in colder waters. We compare the foraging distribution of a common tropical seabird, the masked booby Sula dactylatra, breeding on two islands in the South Atlantic that differ in the size of the breeding seabird community by 2 orders of magnitude, but are surrounded by similar oligotrophic waters. Foraging trips from the island with the smaller colony were on average 221 km (61 %) and 18.0 h (75 %) shorter because birds from the smaller colony rarely spent the night at sea and foraged on average 64 km (46 %) closer to the colony. Energy expenditure was significantly lower, and nest survival higher (47 vs. 37 %, n = 371) on the island with the smaller colony. These results are fully consistent with the predictions from Ashmole’s hypothesis and indicate that competition for food around tropical oceanic seabird colonies may indeed be a limiting factor for populations. Identifying important feeding areas for seabirds based on their foraging range may need to account for colony size of both the target and potential competitor species.

The behavior of pesticides in soil and water is regulated by the properties of the compounds and the media, and by climatic conditions. Important properties include ionizability, water solubility, vapor pressure, soil retention, and longevity. Carboxylic acid herbicides and growth regulators, hydroxy acid pesticides, aminosulfonyl acid herbicides, amide and anilide herbicides, carbamate and carbanilate pesticides, fumigants, and highly water soluble nonionic pesticides are weakly retained by soil colloids and are relatively mobile in soils. Quartemary N pesticides are very highly basic compounds, with very high water solubilities and very low potential for volatilization. Soil organic matter has been the major constituent in soil reported to bind acidic pesticides, but metallic hydrous oxides are also likely to be involved, particularly in tropical soils. The phenylurea pesticides have short to moderate longevity. The chemicals are degraded in soil by microbial degradation, and bacteria are the organisms primarily involved.

Background Proinflammatory biomarkers levels are increased among patients with cardiovascular disease, and it is known that both the presence of insulin resistance and diet may influence those levels. However, these associations are not well studied among patients with established cardiovascular disease. Our objective is to compare inflammatory biomarker levels among cardiovascular disease secondary prevention patients with and without insulin resistance, and to evaluate if there is any association between plasma fatty acid levels and inflammatory biomarker levels among them. Methods In this cross-sectional sub-study from the BALANCE Program Trial, we collected data from 359 patients with established cardiovascular disease. Plasma fatty acids and inflammatory biomarkers (interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-12, high sensitive C-reactive protein (hs-CRP), adiponectin, and tumor necrosis factor (TNF)-alpha) were measured. Biomarkers and plasma fatty acid levels of subjects across insulin resistant and not insulin resistant groups were compared, and general linear models were used to examine the association between plasma fatty acids and inflammatory biomarkers. Results Subjects with insulin resistance had a higher concentration of hs-CRP (p = 0.002) and IL-6 (p = 0.002) than subjects without insulin resistance. Among subjects without insulin resistance there was a positive association between stearic fatty acid and IL-6 (p = 0.032), and a negative association between alpha-linolenic fatty acid and pro-inflammatory biomarkers (p

We investigate coherent electron dynamics in graphene, interacting with the electric field waveform of two orthogonally polarized, few-cycle laser pulses. Recently, we demonstrated that linearly polarized driving pulses lead to sub-optical-cycle Landau-Zener quantum path interference by virtue of the combination of intraband motion and interband transition [Higuchi $\textit{et al.}$, Nature $\textbf{550}$, 224 (2017)]. Here we introduce a pulsed control laser beam, orthogonally polarized to the driving pulses, and observe the ensuing electron dynamics. The relative delay between the two pulses is a tuning parameter to control the electron trajectory, now in a complex fashion exploring the full two-dimensional reciprocal space in graphene. Depending on the relative phase, the electron trajectory in the reciprocal space can, for example, be deformed to suppress the quantum path interference resulting from the driving laser pulse. Intriguingly, this strong-field-based complex matter wave manipulation in a two-dimensional conductor is driven by a high repetition rate \textit{laser oscillator}, rendering unnecessary complex and expensive amplified laser systems.

How does the human brain rapidly process incoming information in working memory? In growing divergence from a single-region focus on the prefrontal cortex (PFC), recent work argues for emphasis on how distributed neural networks are rapidly coordinated in support of this central neurocognitive function. Previously, we showed that working memory for everyday "what," "where," and "when" associations depends on multiplexed oscillatory systems, in which signals of different frequencies simultaneously link the PFC to parieto-occipital and medial temporal regions, pointing to a complex web of sub-second, bidirectional interactions. Here, we used direct brain recordings to delineate the frontoparietal oscillatory correlates of working memory with high spatiotemporal precision. Seven intracranial patients with electrodes simultaneously localized to prefrontal and parietal cortices performed a visuospatial working memory task that operationalizes the types of identity and spatiotemporal information we encounter every day. First, task-induced oscillations in the same delta-theta (2-7 Hz) and alpha-beta (9-24 Hz) frequency ranges previously identified using scalp electroencephalography (EEG) carried information about the contents of working memory. Second, maintenance was linked to directional connectivity from the parietal cortex to the PFC. However, presentation of the test prompt to cue identity, spatial, or temporal information changed delta-theta coordination from a unidirectional, parietal-led system to a bidirectional, frontoparietal system. Third, the processing of spatiotemporal information was more bidirectional in the delta-theta range than was the processing of identity information, where alpha-beta connectivity did not exhibit sensitivity to the contents of working memory. These findings implicate a bidirectional delta-theta mechanism for frontoparietal control over the contents of working memory.

In the Amazonian atmosphere, the aerosol coarse mode comprises a complex, diverse, and variable mixture of bioaerosols emitted from the rain forest ecosystem, long-range transported Saharan dust (we use Sahara as shorthand for the dust source regions in Africa north of the Equator), marine aerosols from the Atlantic Ocean, and coarse smoke particles from deforestation fires. For the rain forest, the coarse mode particles are of significance with respect to biogeochemical and hydrological cycling, as well as ecology and biogeography. However, knowledge on the physicochemical and biological properties as well as the ecological role of the Amazonian coarse mode is still sparse. This study presents results from multi-year coarse mode measurements at the remote Amazon Tall Tower Observatory (ATTO) site. It combines online aerosol observations, selected remote sensing and modeling results, as well as dedicated coarse mode sampling and analysis. The focal points of this study are a systematic characterization of aerosol coarse mode abundance and properties in the Amazonian atmosphere as well as a detailed analysis of the frequent, pulse-wise intrusion of African long-range transport (LRT) aerosols (comprising Saharan dust and African biomass burning smoke) into the Amazon Basin.We find that, on a multi-year time scale, the Amazonian coarse mode maintains remarkably constant concentration levels (with 0.4 cm−3 and 4.0 µg m−3 in the wet vs. 1.2 cm−3 and 6.5 µg m−3 in the dry season) with rather weak seasonality (in terms of abundance and size spectrum), which is in stark contrast to the pronounced biomass burning-driven seasonality of the submicron aerosol population and related parameters. For most of the time, bioaerosol particles from the forest biome account for a major fraction of the coarse mode background population. However, from December to April there are episodic intrusions of African LRT aerosols, comprising Saharan dust, sea salt particles from the transatlantic passage, and African biomass burning smoke. Remarkably, during the core period of this LRT season (i.e., February–March), the presence of LRT influence, occurring as a sequence of pulse-like plumes, appears to be the norm rather than an exception. The LRT pulses increase the coarse mode concentrations drastically (up to 100 µg m−3) and alter the coarse mode composition as well as its size spectrum. Efficient transport of the LRT plumes into the Amazon Basin takes place in response to specific mesoscale circulation patterns in combination with the episodic absence of rain-related aerosol scavenging en route. Based on a modeling study, we estimated a dust deposition flux of 5–10 kg ha−1 a−1 in the region of the ATTO site. Furthermore, a chemical analysis quantified the substantial increase of crustal and sea salt elements under LRT conditions in comparison to the background coarse mode composition. With these results, we estimated the deposition fluxes of various elements that are considered as nutrients for the rain forest ecosystem. These estimates range from few g ha−1 a−1 up to several hundreds of g ha−1 a−1 in the ATTO region.The long-term data presented here provide a statistically solid basis for future studies of the manifold aspects of the dynamic coarse mode aerosol cycling in the Amazon. Thus, it may help to understand its biogeochemical relevance in this ecosystem as well as to evaluate to what extent anthropogenic influences have altered the coarse mode cycling already.

Knowing the spatial scales at which effective management can be implemented is fundamental for conservation planning. This is especially important for mobile species, which can be exposed to threats across large areas, but the space use requirements of different species can vary to an extent that might render some management approaches inefficient. Here the space use patterns of seabirds were examined to provide guidance on whether conservation management approaches should be tailored for taxonomic groups with different movement characteristics. Seabird tracking data were synthesised from 5419 adult breeding individuals of 52 species in ten families that were collected in the Atlantic Ocean basin between 1998 and 2017. Two key aspects of spatial distribution were quantified, namely how far seabirds ranged from their colony, and to what extent individuals from the same colony used the same areas at sea. There was evidence for substantial differences in patterns of space-use among the ten studied seabird families, indicating that several alternative conservation management approaches are needed. Several species exhibited large foraging ranges and little aggregation at sea, indicating that area-based conservation solutions would have to be extremely large to adequately protect such species. The results highlight that short-ranging and aggregating species such as cormorants, auks, some penguins, and gulls would benefit from conservation approaches at relatively small spatial scales during their breeding season. However, improved regulation of fisheries, bycatch, pollution and other threats over large spatial scales will be needed for wide-ranging and dispersed species such as albatrosses, petrels, storm petrels and frigatebirds. Fil: Oppel, Steffen. Royal Society For The Protection Of Birds; Fil: Bolton, Mark. Royal Society For The Protection Of Birds; Fil: Carneiro, Ana P.B.. Birdlife International; Fil: Dias, Maria P.. Birdlife International; Fil: Green, Jonathan A.. University of Liverpool; Reino Unido Fil: Masello, Juan F.. Justus Liebig University Giessen; Fil: Phillips, Richard A.. British Antarctic Survey; Fil: Owen, Ellie. Royal Society For The Protection Of Birds; Fil: Quillfeldt, Petra. Justus Liebig University Giessen; Fil: Beard, Annalea. Environmental And Natural Resources Directorate; Fil: Bertrand, Sophie. Universidad Federal Rural Pernambuco; Brasil. Centre National de la Recherche Scientifique. Institut de Recherche pour le Développement; Francia Fil: Blackburn, Jez. British Trust For Ornithology; Fil: Boersma, P. Dee. University Of Washington, Seattle; Fil: Borges, Alder. Projecto Vitó; Fil: Broderick, Annette C.. University of Exeter; Reino Unido Fil: Catry, Paulo. Ispa - Instituto Universitário; Portugal Fil: Cleasby, Ian. Royal Society For The Protection Of Birds; Fil: Clingham, Elizabeth. Environmental And Natural Resources Directorate; Fil: Creuwels, Jeroen. Naturalis Biodiversity Center; Fil: Crofts, Sarah. Falklands Conservation; Fil: Cuthbert, Richard J.. Royal Society For The Protection Of Birds; Fil: Dallmeijer, Hanneke. Veda Consultancy; Fil: Davies, Delia. University Of Cape Town; Fil: Davies, Rachel. Marinelife; Fil: Dilley, Ben J.. University Of Cape Town; Fil: Dinis, Herculano Andrade. Parque Natural Do Fogo; Fil: Dossa, Justine. Birdlife International; Fil: Dunn, Michael J.. British Antarctic Survey; Fil: Efe, Marcio A.. Universidade Federal de Alagoas; Brasil Fil: Fayet, Annette L.. University of Oxford; Reino Unido Fil: Figueiredo, Leila. Universidade Federal de Alagoas; Brasil Fil: Frederico, Adelcides Pereira. Projecto Vitó; Fil: Gjerdrum, Carina. Environment Canada; Canadá Fil: Godley, Brendan J.. University of Exeter; Reino Unido Fil: Granadeiro, José Pedro. Faculdade de Ciências, Universidade de Lisboa; Portugal Fil: Guilford, Tim. University of Oxford; Reino Unido Fil: Hamer, Keith C.. University Of Leeds; Fil: Hazin, Carolina. Birdlife International; Fil: Hedd, April. Environment Canada; Canadá Fil: Henry, Leeann. Environmental And Natural Resources Directorate; Fil: Hernández-Montero, Marcos. Projeto Biodiversidade; Fil: Hinke, Jefferson. Noaa Fisheries Service; Fil: Kokubun, Nobuo. National Institute Of Polar Research; Fil: Leat, Eliza. Ascension Island Government; Fil: Tranquilla, Laura McFarlane. Royal Society For The Protection Of Birds; . Environmental And Natural Resources Directorate; Fil: Metzger, Benjamin. Birdlife Malta; Malta Fil: Militão, Teresa. Universidad de Barcelona; España Fil: Montrond, Gilson. Projecto Vitó; Fil: Mullié, Wim. Veda Consultancy; Fil: Padget, Oliver. University of Oxford; Reino Unido Fil: Pearmain, Elizabeth J.. Birdlife International; Fil: Pollet, Ingrid L.. Bird Studies Canada; Canadá Fil: Pütz, Klemens. Antarctic Research Trust; Fil: Quintana, Flavio Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Ratcliffe, Norman. British Antarctic Survey; Fil: Ronconi, Robert A.. Environment Canada; Canadá Fil: Ryan, Peter G.. University Of Cape Town; Fil: Saldanha, Sarah. Universidad de Barcelona; España Fil: Shoji, Akiko. University of Oxford; Reino Unido Fil: Sim, Jolene. Ascension Island Government; Fil: Small, Cleo. Royal Society For The Protection Of Birds; Fil: Soanes, Louise. University of Liverpool; Reino Unido Fil: Takahashi, Akinori. National Institute Of Polar Research; Fil: Trathan, Phil. British Antarctic Survey; Fil: Trivelpiece, Wayne. Noaa Fisheries Service; Fil: Veen, Jan. Veda Consultancy; Fil: Wakefield, Ewan. University of Glasgow; Reino Unido Fil: Weber, Nicola. University of Exeter; Reino Unido. Ascension Island Government; Fil: Weber, Sam. Ascension Island Government; . University of Exeter; Reino Unido Fil: Zango, Laura. Universidad de Barcelona; España Fil: González-Solís, Jacob. Universidad de Barcelona; España Fil: Croxall, John. Birdlife International

ZusammenfassungEine gesundheitsbewusste Ernährung bringt unzählige positive Auswirkungen mit sich (15, 18, 26). Um aber der Anforderung, die täglich aufkommenden Essensentscheidungen ernährungsbewußt zu treffen, gerecht zu werden, muss eine tiefgehende Auseinandersetzung mit dem Thema erfolgen. Dabei gilt es nicht nur, sich ernährungstheoretische Grundlagen anzueignen, sondern auch die Hintergründe von Essensentscheidungen zu reflektieren. Im Rahmen dieses Artikels wird eine interdisziplinäre Betrachtung der Einflussfaktoren geboten. Diese werden in äußere (soziokulturelle, situative und produktbezogene) und innere (individuelle, psychologische und physiologische) Einflussfaktoren unterteilt. Die weitere Ausarbeitung macht durch Beispiele deutlich, auf welche Weise die einzelnen Faktoren Essensentscheidungen beeinflussen können. Abschließend zeigen wir auf, wie Essensentscheidungen durch ein Zusammenspiel dieser inter-nen und externen Faktoren zustande kommen.

Carbon nanotubes (CNT) are promising materials for biomedical applications, especially in the field of neuroscience; therefore, it is essential to evaluate the neurotoxicity of these nanomaterials. The present work assessed the effects of single-walled CNT functionalized with polyethylene glycol (SWCNT-PEG) on the consolidation and retrieval of contextual fear memory in rats and on oxidative stress parameters in the hippocampus. SWCNT-PEG were dispersed in water at concentrations of 0.5, 1.0, and 2.1 mg/mL and infused into the rat hippocampus. The infusion was completed immediately after training and 30 min before testing of a contextual fear conditioning task, resulting in exposure times of 24 h and 30 min, respectively. The results showed that a short exposure to SWCNT-PEG impaired fear memory retrieval and caused lipid peroxidation in the hippocampus. This response was transient and overcome by the mobilization of antioxidant defenses at 24 h. These effects occurred at low and intermediate but not high concentration of SWCNT-PEG, suggesting that the observed biological response may be related to the concentration-dependent increase in particle size in SWCNT-PEG dispersions.

This paper covers a silicon photonics technology platform that leverages a commercial semiconductor supply chain for the manufacturing of high performance optical transceivers for high performance computing and hyper-scale data-center applications.

In this paper, the coupling mechanism of a free-space Gaussian beam into a whispering-gallery mode resonator through a dielectric lens is mathematically modeled and numerically solved by means of the Schelkunoff-Waterman method (the so called T-matrix method). This approach allows in principle, to quickly analyze the performance of different near-field coupling mechanisms with arbitrary excitations. The aim is to efficiently excite a WGM into a nonlinear dielectric resonator in order to detect the weak mm-wave radiation from the cosmic microwave background (CMB) by up-converting the signal into the optical domain via the nonlinearity of the medium.

This paper presents an electromagnetic analysis based on an innovative simulation environment and a spherical near field facility well suited to evaluate the near field generated by wireless BAN communication technologies close to an anthropomorphic human mannequin. The interest is to demonstrate the main advantages of these new electromagnetic tools in the theoretical and experimental domains.