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Electrochemical CO2 reduction (ECR) to value-added products is one of the potential ways to utilise CO2 as a feedstock, thereby decreasing its level in the atmosphere as it has harmful repercussions on planet earth. Copper (Cu)-nanostructures have demonstrated a great potential to convert CO2 into valuable higher-end hydrocarbons electrochemically, but with poor selectivity. Therefore, novel strategies to tune Cu-based electrocatalysts' activity and selectivity toward multi-carbon products, particularly at low overpotential, are highly desirable. In the present work, we report an atom-economic strategy to tune the physicochemical properties and the electrocatalytic activity of Cu-nanostructures towards ECR. The Cu-nanostructures synthesized via pulse electrodeposition from an electrolyte bath containing Cu-precursor salts with varying anions (viz. acetates, nitrates, sulphates, and chlorides) are investigated for their effect on the physicochemical properties and the ECR performance. The Cu-electrodeposits having cubic morphology, exposed Cu(100) facets, higher Cu+ content and enhanced electrochemical active surface area demonstrated the best ECR performance depicting good selectivity for ethylene formation.

This chapter introduces economic and monetary union (EMU). It describes the key components of EMU and what happens when countries join. EMU was the result of decades of collaboration and learning, which have been subdivided here into three periods: 1969–91, from the agreement to creation to its inclusion in the Treaty on European Union (TEU); 1992–2002, from having the plans for EMU to the irrevocable fixing of exchange rates; and 2002 onwards, when EMU had been established, and euro banknotes and coins were circulating in member states. Next, the chapter reviews various theoretical explanations, both economic and political, accounting for why EMU was created and looks at some criticisms of EMU. Finally, the chapter discusses how EMU has fared under the global financial crisis, the sovereign debt crisis and the Covid-19 pandemic. These crises brought to the fore various imperfections in the design of EMU and provided opportunities for further development. This section discusses what changes have been made since 2009 to address those flaws and at what may be yet to come.

This chapter explores the implications of the COVID-19 pandemic for the EU’s health policy. Health is an area in which member states have historically been reluctant to cede powers and, consequently, the EU’s competences in health are limited. The chapter first introduces the extent and parameters of the EU’s role and the resulting patchwork of health policy and law which exists at European level. The narrow mandate available to the EU when COVID-19 emerged precluded a comprehensive response, whilst the scale of the emergency put pressure on norms of solidarity and free movement. The chapter’s second section describes the initial period of the pandemic and reviews the EU’s response within six different areas of (health and non-health) policy. It highlights the strengths and weaknesses of the EU’s efforts to fight and mitigate the pandemic using the public health, internal market and fiscal governance dimensions of its health powers. A final section discusses the implications of the pandemic and the EU’s response to it for the future of cooperation and integration in the area of health.

Waning immunity to COVID-19 vaccination is associated with increased risk of breakthrough infection, especially with highly transmissible variants of concern (VOC). Booster vaccination generates rapid immune recall in humans, which real-world observational studies suggest protects against VOC infection and associated disease, and modeling studies suggest could mitigate community spread. We directly tested the impact of booster vaccination on protection against Delta VOC infection, disease, and transmission to naïve cohorts in golden Syrian hamsters. Animals with waning immunity to bnt162b2 generated rapid immune recall and strong protection against upper- and lower-respiratory tract infection when boosted with bnt126b2, mRNA-1273 or AZD1222. Boosting with either mRNA vaccine generated moderate protection against lung inflammation and virus transmission to unvaccinated animals. Our data support booster vaccination as a tool to address emerging VOC in the COVID-19 pandemic.One-Sentence SummaryA booster vaccine delivered 9 months after primary bnt162b2 vaccination protects hamsters from Delta VOC infection, disease, and transmission.

Supercapacitors are efficient and developing energy storage devices. The main focus of this work was on the preparation of reduced graphene oxide supported boron nitride doped-nickel hydroxide [rGO/BN/Ni(OH)2] nanocomposites through a hydrothermal approach, for studying their electrochemical behaviour and specific capacitance by fabricating supercapacitor devices. Pristine BN, BN/Ni(OH)2 and rGO/Ni(OH)2 nanocomposites were also prepared and their use as supercapacitor electrode materials was studied. The structural and morphological properties were characterized using various analytical tools. SEM images showed a spherical shape with a marigold flower-like morphology. The electrochemical behaviour was studied using cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy techniques. The specific capacitances of rGO/BN/Ni(OH)2 in 0.5 M KOH, 1 M KOH, 3 M KOH, and 6 M KOH were 349, 297 F g−1, 143 F g−1, and 94 F g−1, respectively. It was observed that the capacitance increased with a decrease in the electrolyte concentration and the maximum specific capacitance was noted in 0.5 M KOH. Also, a significant increase in energy density and power density in 0.5 M KOH was observed. These results demonstrate that rGO/BN/Ni(OH)2 nanocomposites are a promising electrode material for high-performance energy storage devices.

Purpose: To investigate the outcomes of transcatheter arterial embolization (TAE) for the treatment of peptic ulcer bleeding (PUB). Materials and Methods: This is a retrospective, multicenter study, which investigated all patients who underwent TAE for the treatment of severe upper gastrointestinal hemorrhage from peptic ulcers in five European centers, between January 1, 2012 and May 1, 2017. All patients had undergone failed endoscopic hemostasis. Forty-four patients (male; mean age 74.0 ± 11.1 years, range 49–94), with bleeding from duodenum (36/44; 81.8%) or gastric ulcer (8/44; 18.2%) were followed up to 3.5 years (range 2–1354 days). In 42/44 cases, bleeding was confirmed by pre-procedural CT angiography. In 50% of the cases, coils were deployed, while in the remaining glue, microparticles, gel foam and combinations of the above were used. The study’s outcome measures were 30-day survival technical success (occlusion of feeding vessel and/or no extravasation at completion DSA), overall survival, bleeding relapse and complication rates. Results: The technical success was 100%. The 30-day survival rate was 79.5% (35/44 cases). No patients died due to ongoing or recurrent hemorrhage. Re-bleeding occurred in 2/44 cases (4.5%) and was successfully managed with repeat TAE (one) or surgery (one). The rate of major complications was 4.5% (2/44; one acute pancreatitis and one partial pancreatic ischemia), successfully managed conservatively. According to Kaplan–Meier analysis survival was 71.9% at 3.5 years. Conclusions: TAE for the treatment of PUB was technically successful in all cases and resulted in high clinical success rate. Minimal re-bleeding rates further highlight the utility of TAE as the second line treatment of choice, after failed endoscopy. © 2018, Springer Science+Business Media, LLC, part of Springer Nature and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE).

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Nowadays, the technical advantage between companies in the automotive sector is constantly reducing [Verhoef et al. 2012], leading to most cars being comparatively the same. This trend is due to the increase in quality level of car manufacturers, technology diffusion and platform sharing, leading to most cars being comparatively the same within their market segment. Thus, to be successful a company has to be more than just good at producing quality cars; it has to produce good looking cars, with a meaning. Product aesthetics, integrated with branding, is a major tool that can be used to gain competitive advantage, [Kotler and Rath 1984], [Oakley 1985], [Bloch 1995]. For example, Audi says that the product design determines up to 60% of a consumer’s decision to buy a particular car [Kreuzbauer and Malter 2005]. Furthermore, a product design can be used to represent the brand, commonly referred to as design language in the automotive industry. Thus, branding is essential for the success of the product. Branding is no longer viewed as a separate activity to product design, but the product in itself represents the brand. Arguably, the product is the most important brand representative as during the interaction with the product, the user creates perceptions of the brand [Hestad 2013]. Similarly, the importance of adopting an integrated product development (IPD) approach [Andreasen and Hein 2000] is fundamental since a company must concurrently consider marketing, product design and production. Despite ample evidence on the importance of branding, in several of the product development models reviewed there is no specific reference to branding and how to specifically link it to product design [Cini 2014]. [Excerpt], peer-reviewed

""Auger-photoelectron coincidence spectroscopy is used for investigating the electronic properties of a CoO thin film above and below the magnetic transition temperature (T(N)). By using the dichroic effect in angle-resolved measurements, we identify and assign well-defined high-spin and low-spin structures in spite of the otherwise featureless Auger singles spectra, typically found for open-band systems. The disappearance of the dichroism for temperatures just above T(N) indicates a collapse of the surface short-range magnetic order, presumably due to a strongly reduced exchange field in the surface compared to that in the bulk. Copyright (C) EPLA, 2011""

We propose an ab initio method to evaluate the core-valence-valence Auger spectrum of systems with filled valence bands. The method is based on the Cini-Sawatzky theory and aims at estimating the parameters by first-principles calculations in the framework of density-functional theory (DFT). Photoemission energies and the interaction energy for the two holes in the final state are evaluated by performing DFT simulations for the system with varied population of electronic levels. Transition matrix elements are taken from atomic results. The approach takes into account the nonsphericity of the density of states of the emitting atom, spin-orbit interaction in core and valence, and nonquadratic terms in the total-energy expansion with respect to fractional occupation numbers. It is tested on two benchmark systems, Zn and Cu metals, leading in both cases to L23M45M45 Auger peaks within 2 eV from the experimental ones. Detailed analysis is presented on the relative weight of the various contributions considered in our method, providing the basis for future development. Especially problematic is the evaluation of the hole-hole interaction for systems with broad valence bands: our method underestimates its value in Cu, while we obtain excellent results for this quantity in Zn.

BACKGROUND AND OBJECTIVES: High levels of factor VIII are a common risk factor for venous thromboembolism (VTE). The aim of this study was to evaluate the possible interaction between the presence of high factor VIII levels and oral contraceptive (OC) use. DESIGN AND METHODS: Factor VIII levels were measured by a chromogenic assay in 174 women who suffered from VTE in reproductive age and in 484 healthy women. Subjects carrying thrombophilic alterations were excluded. RESULTS: Factor VIII levels were stratified into quartiles. The adjusted odds ratio (OR) of VTE in subjects with factor VIII levels in the upper quartile (>1.95 IU/mL) was 7.45 (95%CI: 3.80-14.6). Among the 174 patients, 85 had experienced VTE during OC use. The 179 healthy women who had used OC for at least 6 months in the two years before presentation but had stopped OC at least 3 months before the blood sampling were considered as OC users. The risk of VTE among OC users with factor VIII levels in the upper quartile was increased about 13-fold (OR: 13.0, 95% CI: 4.92-34.3). INTERPRETATION AND CONCLUSIONS: Our results showed that there is an increased risk of VTE due to oral contraceptive use in women with elevated factor VIII and, as has been previously described for factor V Leiden and G20210A prothrombin mutations, the raised level of the coagulation factor and oral contraceptive use seem to have a synergistic effect.

This work arises from our teaching this subject during many years. The vast majority of these exercises are the exams we gave to our students in this period. We carefully selected the subjects of the exercises to cover all the material which is most needed and which is treated in the most well known texts on these subjects. Each exercise is carefully solved in full details, explaining the theory behind the solution with particular care for those issues that, from our experience, are found most difficult from the average student. Indeed, several exercises are designed to throw light on aspects of the theory that, for one reason or another, are usually neglected with the result to make the students feel uneasy about them. In fact most students get acquainted just with the more common manipulations, which are illustrated by many examples in textbooks. Our exercises never require extensive calculations but tend to be somewhat unusual and force the solver to think about the problem starting from the principles, rather than by analogy with some previously solved exercise.

The effects of long-range interactions in quantum transport are still largely unexplored, mainly due to the difficulty of devising efficient embedding schemes. In this work we present a substantial progress in the interacting resonant level model by reducing the problem to the solution of Kadanoff-Baym-like equations with a correlated embedding self-energy. The method allows us to deal with short- and long-range interactions and is applicable from the transient to the steady-state regime. Furthermore, memory effects are consistently incorporated and the results are not plagued by negative densities or non-conservation of the electric charge. We employ the method to calculate densities and currents with long-range interactions appropriate to low-dimensional leads, and show the occurrence of a jamming effect which drastically reduces the screening time and suppresses the zero-bias conductance. None of these effects are captured by short-range dot-lead interactions., Comment: 5 pages, 4 figures

The antibacterial and antioxidant activities of essential oils from Bitter orange, Sweet orange, Lemon and Mandarin were investigated. The antimicrobial capability of these oils was determined against ten strains of Gram-negative and Gram-positive bacteria, including some phytopathogenic strains. The antibacterial activity of the oils was expressed as minimum inhibitory concentrations (MICs). All oils showed good antibacterial activity against both Gram-negative and Gram-positive bacteria. The MICs for selected oils ranged 15-250 mu g/mL. The lowest MICs were 15 mu g/mL and 20 mu g/mL against Xanthomonas citri strains, respectively. The antioxidant and antiradical scavenging properties of the selected oils were tested by means of 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. All examined oils exhibited a free radical scavenging activity, ranging 20-70% of DPPH inhibition. Lemon oil showed the most antioxidant capacity, with DPPH inhibition rate of 70%.

We discuss and compare different approximations to the particle-particle response function in the p - d (three-band) Hubbard model for the CuO 2 plane of superconducting cuprates. Besides the relevance for understanding the role of correlations in high- T c superconductors, the interest in the CuO 2 plane is due to the presence of three incompletely filled valence bands. The bare ladder approximation (BLA) was employed long ago in the context of Auger core-valence-valence spectroscopy of late transition metals while the time-dependent (TD) Gutzwiller approximation (GA) is a much more sophisticated and recent development. The validity of both is assessed by comparing with exact-diagonalization results from a finite six-site cluster. We find that for standard parameter sets TDGA and BLA yield two-hole spectra in excellent agreement with the exact ones. Although the interaction is comparable to the kinetic energy, the system is far from the extreme Mott limit often assumed in cuprates, where the Mott insulating character is completely local. In order to identify possible fingerprints of the extreme Mott regime we artificially reduce the bandwidth. We find that the BLA breaks down while the TDGA keeps near the exact results. Our findings provide a simple criterion to identify doped and undoped extreme Mott insulators.

We propose an ab initio method to evaluate the core-valence-valence (CVV) Auger spectrum of systems with filled valence bands. The method is based on the Cini-Sawatzky theory, and aims at estimating the parameters by first-principles calculations in the framework of density-functional theory (DFT). Photoemission energies and the interaction energy for the two holes in the final state are evaluated by performing DFT simulations for the system with varied population of electronic levels. Transition matrix elements are taken from atomic results. The approach takes into account the non-sphericity of the density of states of the emitting atom, spin-orbit interaction in core and valence, and non quadratic terms in the total energy expansion with respect to fractional occupation numbers. It is tested on two benchmark systems, Zn and Cu metals, leading in both cases to L23M45M45 Auger peaks within 2 eV from the experimental ones. Detailed analysis is presented on the relative weight of the various contributions considered in our method, providing the basis for future development. Especially problematic is the evaluation of the hole-hole interaction for systems with broad valence bands: our method underestimates its value in Cu, while we obtain excellent results for this quantity in Zn., 20 pages, 5 figures, 4 tables

This book provides material for courses in theoretical physics for undergraduate and graduate students specializing in condensed matter, including experimentalists who want a thorough theoretical background; the advanced part should be of interest to research workers too. A good first course in quantum mechanics is assumed. Here a variety of many-body phenomena in condensed matter are discussed, with special attention paid to the understanding of strong correlation effects. This requires a variety of theoretical tools (diagram expansions, groups, recursion methods and more). The text, which arose naturally from teaching, is eminently readable and the mathematical treatments are explained in enough detail to be followed easily. Proofs of all the relevant theorems are provided, but the main emphasis is always on the physical meaning or applicability of the results. Many examples are provided for illustration and also serve as worked problems.

A theoretical analysis of the superconductivity observed recently in Carbon nanotubes is proposed. We argue that ultra-small (diameter $ \sim 0.4 nm$) single wall carbon nanotubes (with transition temperature $T_c\sim 15 ^{o}K$) and entirely end-bonded multi-walled ones ($T_c\sim 12 ^{o}K$) can superconduct by an electronic mechanism, basically the same in both cases. By a Luttinger liquid -like approach, one finds enhanced superconducting correlations due to the strong screening of the long-range part of the Coulomb repulsion. Based on this finding, we perform a detailed analysis on the resulting Hubbard-like model, and calculate transition temperatures of the same order of magnitude as the measured ones., Comment: 6 pages, 1 figure, PACS: 71.10.Pm,74.50.+r,71.20.Tx, to appear in Phys. Rev. B

Zinc is a common element in human and natural environments and plays an important part in many biological processes. Zinc, which is defined as “essential trace element”, or a “micronutrient”, is essential for the normal growth and the reproduction of all higher plants, animals and of humans. In addition, it plays a key role during physiological growth and fulfils an immune function. It is vital for the functionality of more than 300 enzymes, for the stabilization of DNA and for gene expression. This review summarizes the role and manifestations of zinc in the environment, its importance for human health, metabolism, as well as its physiological role. Toxicity, teratogenicity, carcinogenicity, and immunological functions of zinc are outlined with particular reference to the properties of zinc as an antioxidant, and its role in cancer prevention .

In this paper, the use of a mobile code, partly interpreted language, such as Java, is investigated as a tool to build highly portable implementations of multimedia real time applications. In particular, we concentrate on the implementation of an audio-conference tool. First, we evaluate the efficiency of some Java implemented basic functionality in the real time processing of audio flows. Second, we produce a suitable object oriented design of the tool. Third, the tool has been entirely implemented in Java, with the only exception of some specific audio devices drivers. Finally, we evaluate the tool implementation effectiveness. The obtained results affirm the potentiality of Java in the design and the implementation of real time multimedia applications.