Nanometers-thick self-organized Fe stripes: bridging the gap between surfaces and magnetic materials

We have fabricated 5nm-high Fe(110) stripes by self-organized (SO) growth on a slightly vicinal R(110)/Al2O3(11-20) surface, with R=Mo, W. Remanence, coercivity and domain patterns were observed at room temperature (RT). This contrasts with conventional SO epitaxial systems, that are superparamagnetic or even non-magnetic at RT due to their flatness. Our process should help to overcome superparamagnetism without compromise on the lateral size if SO systems are ever to be used in applications

Improved convergence estimates for the Schröder-Siegel problem

We reconsider the Schröder–Siegel problem of conjugating an analytic map in ℂ in the neighborhood of a fixed point to its linear part, extending it to the case of dimension n>1 . Assuming a condition which is equivalent to Bruno’s one on the eigenvalues λ1,…,λn of the linear part, we show that the convergence radius ρ of the conjugating transformation satisfies lnρ(λ)≥−CΓ(λ)+C′ with Γ(λ) characterizing the eigenvalues λ , a constant C′ not depending on λ and C=1 . This improves the previous results for n>1 , where the known proofs give C=2 . We also recall that C=1 is known to be the optimal value for n=1

Temperature dependence of surface stress across an order-disorder transition: p(1x2)O/W(110)

Strain relaxations of a p(1x2) ordered oxygen layer on W(110) are measured as a function of temperature across the disordering transition using low-energy electron diffraction. The measured strains approach values of 0.027 in the [1-10] and -0.053 in the [001] direction. On the basis of the measured strain relaxations, we give quantitative information on temperature-dependent surface stress using the results of ab initio calculations. From the surface formation energy for different strains, determined by first-principles calculations, we estimate that surface stress changes from -1.1 for the ordered phase to -0.2N/m for the disordered one along [1-10], and from 5.1 to 3.4 N/m along [001]. Moreover, our observation that the strains scale inversely with domain size confirms that the strain relaxation takes place at the domain boundaries.Comment: 8 pages, 5 figure

Retrospective analysis of the cholesterol levels in a european mid-latitude population between 2007 and 2018: Controversies and therapeutic implications

Background and aim of the work: Coronary heart disease is the leading cause of morbidity and mortality in developed countries and its association with LDL-cholesterol has been well established. During the last decades statin therapy, and an healthy lifestyle, has proven highly effective in reducing cardiovascular event rates. Yet, there is still controversy among national guidelines and clinical practice with regard to LDL-cholesterol measurements. The aim of this study was to verify whether significant changes in cholesterol levels were observed over a relatively long (12 years) period. We also compared the Friedewald-calculated with directly-measured LDL cholesterol in order to verify whether the two methods were equivalent. Meth-ods: We retrospectively analyzed 288000 data (total cholesterol, HDL, LDL both directly-measured and Friedewald-calculated, and triglycerides), from 57600 individuals, collected at the San Raffaele Hospital in Milan between 2007 and 2018. Data were statistically analyzed using a linear regression over the 12 years long period of time. Results: We observed a general decreasing trend in total cholesterol (and an increasing trend in HDL) and a decrease in triglycerides only in the male group. Directly-measured LDL did not cor-relate well with calculated LDL. Conclusion: The total cholesterol decrease and the corresponding increment in HDL was attributed to either an increased use of statin and/or an improvement of the general population dietary habits. The latter was further confirmed by the decrease in triglycerides observed in the male group. Based on our data, an alternative method for assessing atherogenics lipoproteins level has been proposed. (www.actabiomedica.it)

Strain relaxation in small adsorbate islands: O on W(110)

The stress-induced lattice changes in a p(1x2) ordered oxygen layer on W(110) are measured by low-energy electron diffraction. We have observed that small oxygen islands show a mismatch with the underlying lattice. Our results indicate that along [1-10] the average mismatch scales inversely with the island size as 1/L for all oxygen coverages up to 0.5 ML, while along [001] it is significant only for the smallest oxygen islands and scales as a higher power of the inverse island size. The behaviour along [1-10] is described by a one-dimensional finite-size Frenkel-Kontorova model. Using this model, together with calculated force constants, we make a quantitative estimate for the change of surface-stress upon oxygen adsorption. The result is consistent with our ab-initio calculations, which give a relative compressive stress of -4.72 N/m along [1-10] and a minute relative tensile stress of 0.15 N/m along [001]. The scaling along [001] is qualitatively explained as an effect induced by the lattice relaxation in the [1-10] direction.Comment: 22 pages, 5 figure

Spectro-microscopy of single and multi-layer graphene supported by a weakly interacting substrate

We report measurements of the electronic structure and surface morphology of exfoliated graphene on an insulating substrate using angle-resolved photoemission and low energy electron diffraction. Our results show that although exfoliated graphene is microscopically corrugated, the valence band retains a massless fermionic dispersion, with a Fermi velocity of ~10^6 m/s. We observe a close relationship between the morphology and electronic structure, which suggests that controlling the interaction between graphene and the supporting substrate is essential for graphene device applications.Comment: 10 pages of text, 4 JPEG figure

Atributos químicos e físicos de um Latossolo e rendimento de milho em diferentes sistemas de manejo da capoeira.

Este trabalho teve como objetivo avaliar os atributos químicos e físicos de um Latossolo e o rendimento de milho em diferentes sistemas de manejo da capoeira. Os atributos de solo avaliados foram: resistência do solo ao penetrômetro, determinada no campo, densidade de solo, matéria orgânica do solo, pH-H2O, cálcio e magnésio trocáveis (KCl 1M), alumínio trocável (KCl 1M), acidez titulável (H+Al) e potássio extraíveis (Mehlich 1).bitstream/CPAF-RO-2010/14573/1/352-milho.pd

Interação de micorriza vesicular-arbuscular com leguminosas em solos ácidos.

Este trabalho apresenta uma abordagem para MVA e acidez do solo; Simbiose MVA ? Rhizobium-leguminosa; Dependência de MVA e Micorrizas e pesquisa na região amazônica.bitstream/item/60903/1/Doc55-micorrizaarbuscular.pd

Yes, construction cost, time and scope are important, but there is more: a new action plan for infrastructure success

Purpose: During the planning and delivery, iron triangle criteria, are essential for internal stakeholders (e.g. owner, sponsors and delivery company), mostly ignoring external stakeholders such as local communities (often perceived as inconvenient) or end users. In the medium-long term, infrastructure cost and benefit are far more important for external stakeholders and the environment. Design/methodology/approach: The iron triangle criteria, i.e. delivering on time, budget and quality/scope, is the traditional perspective to assess the success of infrastructure projects. Delivering on cost and time is significant, but particularly for infrastructure, there are more relevant success criteria. The authors argue which criteria are important, and explain why. Findings: The authors challenge the traditional view of judging projects based on respecting time, budget and quality/scope. The authors explain that discussing the social value and contribution to achieving the UN Sustainable Development Goals (SDGs) is extremely relevant. Crucially these metrics keep changing, even after the project is terminated. Originality/value: The authors provide a new seven-step action plan for decision-makers to improve infrastructure provision by reflecting on SDGs and engaging with external stakeholders, particularly minorities and the weaker members of their communities. Such an action plan is focused on the cost and value for different stakeholders on different timeframes and progress toward social value and achieving SDGs