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Emergency clinicians have a crucial role during public health emergencies and have been at the frontline during the COVID-19 pandemic. This study examined the knowledge, preparedness and experiences of Australian emergency nurses, emergency physicians and paramedics in managing COVID-19. A voluntary cross-sectional study of members of the College of Emergency Nursing Australasia, the Australasian College for Emergency Medicine, and the Australasian College of Paramedicine was conducted using an online survey (June-September 2020). Of the 159 emergency nurses, 110 emergency physicians and 161 paramedics, 67.3–78% from each group indicated that their current knowledge of COVID-19 was 'good to very good'. The most frequently accessed source of COVID-19 information was from state department of health websites. Most of the respondents in each group (77.6–86.4%) received COVID-19 specific training and education, including personal protective equipment (PPE) usage. One-third of paramedics reported that their workload 'had lessened' while 36.4–40% of emergency nurses and physicians stated that their workload had 'considerably increased'. Common concerns raised included disease transmission to family, public complacency, and PPE availability. Extensive training and education and adequate support helped prepare emergency clinicians to manage COVID-19 patients. Challenges included inconsistent and rapidly changing communications and availability of PPE. [ABSTRACT FROM AUTHOR]

A family of one parametric infinitely differentiable hyperelastic potentials for three-dimensional problems of bimodular isotropic materials at infinitesimal strain is constructed, yielding a set of uniform approximations to the discontinuous stepwise elastic modulus adopted in the original one-dimensional bimodular formulation. The introduced potentials enable either analytical solutions or construction of the explicit governing equations for a number of static and dynamic problems. Theorem of convergence to the discontinuous bimodular modulus is proved. • A family of one parametric hyperelastic potentials is constructed. • A set of uniform approximations to the discontinuous stepwise elastic moduli is introduced. • Analytical solutions for construction of explicit equations for static and dynamic problems are developed. • Theorem of convergence to the discontinuous bimodular modulus is proved. [ABSTRACT FROM AUTHOR]

Nonlinear torsional waves propagating in cylindrical shells made of hyperelastic material obeying Ogden model, are studied by a combined approach comprising theoretical and finite element analysis. It was found, apparently for the first time, that delta-like pulses of torsional waves attenuate with distance due to the appearance of shock wave fronts. Moreover, both strain and kinetic mechanical energy dissipate due to the release of thermal energy. • Nonlinear torsional waves are analyzed. • Ogden hyperelastic potential is introduced. • Delta-like pulse propagation in a thin cylindrical shell is analyzed. • The appearance of shock wave fronts is observed. • Finite element approach is used. [ABSTRACT FROM AUTHOR]

Topology optimization is used to obtain a magnetic source distribution providing levitation of a diamagnetic body or type I superconductor with maximized thrust force. We show that this technique identifies non-trivial source distributions and may be useful to design devices based on non-contact magnetic suspension and other magnetic devices, such as micro-magneto-mechanical devices, high field magnets etc. Diamagnetic and superconducting suspensions are often used in physical experiments and thus we believe this approach will be interesting to physics community as it may generate non-trivial and often unexpected topologies and may be useful to create new experiments and devices. [ABSTRACT FROM AUTHOR]

The paper presents the characteristics of thermal effects in wind-tunnel simulations of the atmospheric boundary layer (ABL) flow developing above complex terrain. The differences and instable stratification effects between the windward and leeward sides of a hill model were investigated for different wind characteristics. Particularly, the buoyancy effects on the structure of the ABL simulation in a wide range of stability conditions expressed by Richardson number are studied. [ABSTRACT FROM AUTHOR]

Lamb waves propagating in a layered structure consisting of layers with equal acoustic impedances, is studied by a variant of Cauchy sextic formalism and the exponential fundamental matrix method. It is shown that the dispersion portraits provide enough information to distinguish individual layers, even if their acoustic impedances are identical, making such layers indistinguishable by the pulse – echo method. It is revealed that the developed methodology is adequate for determining geometrical and physical properties of the individual layers with equal acoustic impedances. [ABSTRACT FROM AUTHOR]

The evolution of the wave spectrum is important, because often initial wave parameters necessary for modeling and coastal engineering tasks are obtained on the basis of spectral characteristics. The wave spectra evolution over mild sloping bottom was studied. The data of laboratory experiments were used for spectral and bispectral analysis. The spectrum maximum frequency downshifting with discrete step (i.e. the cascade downshifting) was revealed. Its peculiarities depending on initial wave parameters and spectrum width were investigated. The cascade frequency downshifting occurs due to nonlinear processes and difference triad interactions between a) main frequencies of wave spectrum and infragravity frequencies and b) the frequencies of second harmonics and the new forming low-frequency peak in the main frequency range. According to laboratory experimental data the initial spectrum width determines the frequency step of downshifting and the number of cascades. The wider the initial wave spectrum, the less numbers of cascades are observed. It was shown that wave energy dissipation due to wave breaking is not a main reason for peak frequency downshifting and it has no direct influence on this process. The variability of the main wave period due to the cascade peak frequency downshifting can be important for engineering models because many calculations assume a constant wave period in the coastal zone. • During the transformation of waves over a mild slope bottom the peak spectrum frequency is not constant and the frequency downshifting is observed. • The main mechanism of peak frequency downshifting is the difference nonlinear triad interactions between them and infragravity frequencies. • The difference nonlinear interactions between the peak frequency and higher harmonics also contribute in frequency downshifting process. • Discrete multi-step frequency downshifting revealed or by other words - cascade downshifting. • The features of cascade downshifting depending on the wave's parameters are discussed. [ABSTRACT FROM AUTHOR]

On the base of laboratory experiments the nonlinear wave transformation above submerged rectangular permeable and solid bars was investigated. A transmission coefficient and a change of mean wave period as parameters of wave transformation were considered. Both of these parameters can characterize an ability of submerged structure to reduce a wave impact in coastal zone. It was revealed that for decreasing of mean wave period solid submerged bar is more effective, but permeable bar is more effective for decreasing of wave height. The optimal relations for transmission coefficient and change of mean wave period in dependence of parameters of bar and waves were revealed. For decreasing of wave mean period the optimal length of solid bar must be 0.4 of initial wavelength and 0.1 - for permeable bar. For decreasing of wave height the length of bar for permeable bar must be 0.21 of initial wavelength and for solid bar - 0.55. It was revealed that maximal decreasing of mean wave period will be at relative depth of bar 1.25 independently of permeability of bar. The optimal relation between transmission coefficient and changes of mean wave period depends on wave steepness. [ABSTRACT FROM AUTHOR]

Dispersion of guided waves propagating in layered media containing layers with equal acoustic impedances is analyzed by Cauchy sextic formalism coupled with the exponential fundamental matrix method. The cases of layers with equal acoustic impedances apparently have not been studied yet. However, dispersion in such a medium exhibits several peculiarities that may be essential for developing the acoustic non-destructive testing methods. • Dispersion of guided waves propagating in layered media containing layers with equal acoustic impedances is analyzed. • Cauchy sextic formalism coupled with the exponential fundamental matrix method is used. • The cases of layers with equal acoustic impedances are studied. • Dispersion exhibits the anomalous behavior. • The outer layers become invisible. [ABSTRACT FROM AUTHOR]

The Black Sea basin is a unique and very complex environment in the World Ocean as a result of its evolution, location and history. This is the reason why in the last years there is an increasing scientific interest in deciphering the processes and mechanisms governing this area. Besides the well-known environmental problems of the basin related to pollution, eutrophication, overfishing and loss of biodiversity, erosion (as a result of storminess, sea level rise and human interventions) is affecting many coasts around the Black Sea. This paper deals with an evaluation of the erosion hazards along the Black Sea coasts, (through an in-depth and well-grounded scientific analysis of a comprehensive database of multiple sources), together with the discussion of erosion management issues at basin scale (through literature review and risk perceptions analysis related to planning strategies, protection measures, legislation and administrative implementation). For this endeavour, we have computed a Coastal Sensitivity Index (CSI) at 1-km spatial scale for more than 4000 sectors around the Black Sea, taking into consideration geological–geomorphological and physical characteristics of each sector through the following parameters: type of coast (coastal geomorphology and lithology), coastal slope (from shoreline to 20 m depth), shoreline changes in the last 33 years, wave incidence (the angle between the shoreline and the dominant storm waves), significant wave height during storm conditions and relative sea level rise. The results for each parameter are detailed and statistically presented and are finally aggregated into CSI. Results showed circa 19% (800 km) of the Black Sea coasts are undergoing serious erosion, affecting mostly the coastlines of Romania (37%), Ukraine (29%) and Georgia (26%). The most sensitive sectors to erosion are superposed on the areas with relatively high storm waves and incidence angles: the deltaic coastlines of the main deltas (Danube, Kizilirmak, Yesilirmak, Sakarya, Rioni, Enguri, Kodori, Chorokhi) of the Black Sea, the low-lying areas along the lagoons, limans, coastal barriers and spits from Kalamitsky, Odessa and Karkinitsky Bays (Dniester, Tendrovskaya and Dzharlygachskiy areas), Chornomorske – Yevpatoriya area (in Crimea), Taman – Anapa (in Russia) and Karasu – Karaburun (in Turkey) and the rocky areas Gelendzhik – Tuapse (in Russia), Sevastopol – Cape Meganom (in Crimea) and Inebolu – Eregli (in Turkey). These highly sensitive sectors cover extensive areas along the coastlines of Russia (57%), Georgia (46%), Turkey (44%), Romania (43%) and Ukraine (35%). Implications of coastal erosion management in the Black Sea riverine countries (with different coastal legislation, EU/non-EU regulations and directives etc.) are discussed, emphasizing the main problems and shortcomings. Some guidelines for coastal erosion management in the specific case of the Black Sea are listed at the end of the paper. Despite the complicated regional geo-political context, common framework of coastal erosion management for the entire Black Sea basin is needed at all levels (political, administrative, academics and research) through cross-border cooperation related to legislation, regulations (integrated approaches for Marine Spatial Planning and Coastal Zone Management), research and academic programs, coastal zone monitoring, management/planning (prioritization of protection works and promotion of soft engineering measures) and public participation. • Coastal erosion is a serious problem along the Black Sea coasts. • 19% (800 km) of the coast is experiencing erosion rates higher than 1 m/yr. • Overview, description and explanation of the different variables used for Coastal Sensitivity Index (CSI) computation. • Lack of proper coastal erosion management strategies, regulations and frameworks in the riverine countries. • Need for integrated basin scale MSP and ICZM approaches. [ABSTRACT FROM AUTHOR]

• Heat capacity and cell parameters of TmB 2 C at 2–300 K are experimentally studied. • The impact of crystal field on TmB 2 C heat capacity has been revealed. • Thermal expansion of TmB 2 C in the basal plane is almost missing. • Anomalies in thermal expansion are due to magnetic phase transition and CEF impact. Temperature dependences of heat capacity C P (T) and lattice parameters a(T) , b(T), c(T) of thulium carboboride TmB 2 C at 2–300 K were experimentally studied. Magnetic phase transition in the carboboride – 'paramagnetic – antiferromagnetic' at T N = 11.0 K was revealed. By comparison with the diamagnetic LuB 2 C the Schottky contribution to TmB 2 C heat capacity due to the crystal electric field (CEF) was calculated. The splitting scheme of Tm3+ ion f – level by the crystal field was suggested. It was obtained that in the temperature range under study (5–300 K) TmB 2 C carboboride thermal expansion in the basal plane is almost missing (anisotropic invar effect, linear thermal expansion coefficient α a (T) ≃ α b (T) ≃ 0). It is, seems, a common property of the lattice dynamics of layered carboborides. The anomalies in the thulium carboboride thermal expansion are due to the magnetic phase transition and the CEF influence. [ABSTRACT FROM AUTHOR]

Diamond-based X-ray luminescent composites are robust materials to be used in synchrotrons and free-electron lasers to detect and visualize high-intensity X-ray beams. Such composites consist of luminescent rare-earth (RE) particles embedded into an X-ray transparent diamond matrix. In this work, polycrystalline diamond composites with embedded particles of EuF 3 , SrF 2 :Eu and YAG:Ce were grown by microwave plasma CVD using diamond seeds with an average particle size difference of two orders of magnitude: from 5 nm up to 500 nm, with positive and negative zeta potentials. The structure, phase composition, and luminescent characteristics of the resulting composite films were investigated and analyzed. We found that various particle types can be better-suited for different composites, and the exact seeding should be selected on the case-by-case basis. The direct comparison of various diamond-based composites, grown in the identical CVD conditions but with various luminescent powders, show that YAG:Ce particles in diamond allow achieving a brighter photoluminescence (PL) in comparison to Eu-based fluorides. However, the set of fluoride powders doped with Eu3+ ions allow obtaining unusually narrow (FWHM = 0.9 nm) and intensive line near 611 nm in PL spectra, which might be better-suited for detection and characterization applications rather than a broad peak of Ce with FWHM ≈ 120 nm. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights: [•] Heracleum sosnowskyi M. arabinogalactan protein (AGP) structure was characterised. [•] Polysaccharide carbohydrate backbone consisted of 1,3-β-d-galactopyranosyl residues. [•] Polysaccharide side chains consisted of 1,6-β-d-Galp, 1,5-α-l-Araf, and 4-ОMe-β-d-GlcpA. [•] Polysaccharide branching points are comprised of 1,3,6-β-d-galactopyranose residues. [ABSTRACT FROM AUTHOR]

Abstract: Co-precipitation of barium and yttrium fluorides from aqueous solutions at room temperature produced non-equilibrium Ba1−x Y x F2+x nanofluoride phase with face-centered cubic crystal lattice of fluorite-type with the composition interval of the homogeneity for x =0.35–0.75. Lattice parameter a of this solid solution nanophase varied as a function of the sample chemical composition in a complex manner with two areas of linear dependency, from x =0.35 to 0.45 and from x =0.50 to 0.75. A plausible explanation of this phenomenon included a change of the type of crystal lattice defects and the manner of their population with the corresponding ions. An increase of the relative amount of yttrium in the HF reaction system led to the formation of hydroxonium salt of decafluorotriyttrium acid, (H3O+)Y3F10 −·nH2O, instead of expected YF3 hydrate. No formation of oxyfluoride phases under acidic conditions has been observed. [Copyright &y& Elsevier]