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Abstract The basal dislocations play a key role in the deformation of hexagonal Mg alloys. However, its core structure and mechanical behavior have thus far not yet been understood adequately, largely owing to the fact that the basal dislocation, often decorated with segregated solute atmosphere and dissociated into two partials, cannot be modeled accurately. Significant discrepancies exist between theoretically calculated and experimentally observed structures for these dissociated dislocations. Here we present a comprehensive theoretical scheme to model them in the Mg alloys with alloying elements of Y, Zn, Al and Li, respectively. Firstly, solute–dislocation interactions were computed by appropriate first-principles calculations. Secondly, the statistic solute concentration at a dislocation is estimated by a Fermi–Dirac distribution. Finally, all these effects on dislocations are integrated into an improved two-dimensional Peierls–Nabarro model to predict their core structures and mechanical behaviors in Mg alloys. It is shown that although Zn, Al and Li atoms have little effect on basal dislocations, Y atoms can largely increase their dissociated width. Furthermore, when it moves from its ground state configuration, the dissociated dislocation can further be widened, such that its dissociated widths in a Mg–0.8Y (at%) alloy at 300 K can reach 12–36 nm, in rather good agreement with the experimentally observed values of 20–30 nm. Besides, the Peierls and yield stresses of Mg alloys shall increase with increasing added solute concentration, while they are decreased drastically with increasing the temperature from 300 to 800 K, but with the Mg-Y alloy as somewhat exception, which is again consistent with experimental observations.

Abstract We propose a novel model-selection method for dynamic networks. Our approach involves training a classifier on a large body of synthetic network data. The data is generated by simulating nine state-of-the-art random graph models for dynamic networks, with parameter range chosen to ensure exponential growth of the network size in time. We design a conceptually novel type of dynamic features that count new links received by a group of vertices in a particular time interval. The proposed features are easy to compute, analytically tractable, and interpretable. Our approach achieves a near-perfect classification of synthetic networks, exceeding the state-of-the-art by a large margin. Applying our classification method to real-world citation networks gives credibility to the claims in the literature that models with preferential attachment, fitness and aging fit real-world citation networks best, although sometimes, the predicted model does not involve vertex fitness.

OECD reports a mismatch between field of study and job content for Humanities students, while at the same time signalling labour market shortages for skills that seem clearly linked with the Humanities, e.g. delivering information. In order to investigate which skills Humanities students associate with their university studies, we conducted a survey among 1306 European Humanities and 231 non-Humanities students. The survey asked these students whether they felt they acquired skills during their Humanities university education which were identified in a pilot phase. The students' answers were analysed quantitatively, arriving at a Humanities self-perception skills profile of 70 detailed descriptions of skills that fall under six clusters. We argue that this profile could be a crucial step to improve the employability of Humanities students, as students' perceptions of their skills greatly determine the quality of transition to the labour market.

Background: Vitality is a relatively unresearched concept and defined in existing literature either on the premise of one's functioning, or in terms of feeling alive. There is, however, little known about the significance of a sense of connectedness to life for vitality, especially from the perspective of older adults. This research aims to explore the association between the concept of connectedness and the perspective of vitality as a sense of aliveness, in order to formulate a theoretical understanding grounded in the subjective perceptions that older adults themselves hold of vitality. Methods: Following a constructivist grounded theory approach and theoretical sampling, constant comparative analysis was performed on the transcripts of 15 semi-structured interviews, conducted in the Netherlands with older adults (mean age 73 years, eight females and seven males), regarding their vitality. Concurrently, empirical and theoretical findings were translated into a theoretical conceptualisation. Results: According to the older participants, connecting to life itself enhanced their sense of vitality. This connection was achieved through internal connectedness (connecting to one's own life, intrinsic stimuli and intrinsic goals in an independent manner) and external connectedness (social connectedness, environmental connectedness, engagement with the external world). Furthermore, our findings revealed distinct interactions between internal and external connectedness and facilitating tools, such as freedom from physical constraints, financial freedom and adaptation. Conclusions: Our findings provide a holistic concept of vitality and connectedness and consolidate existing perspectives on vitality into an overarching framework, which can contribute to the development of effective care policy, healthcare interventions and welfare services.

Background: Whenever possible, a person should die where they feel it is the right place to be. There is substantial global variation in home death percentages but it is unclear whether these differences reflect preferences, and there are major limitations in how the place of death is classified and compared across countries. Objectives: EOLinPLACE is an international interdisciplinary research project funded by the European Research Council aiming to create a solid base for a ground-breaking international classification tool that will enable the mapping of preferred and actual places towards death. Design: Mixed-methods observational research. Methods and analysis: We combine classic methods of developing health classifications with a bottom-up participatory research approach, working with international organizations representing patients and informal carers [International Alliance of Patients’ Organizations (IAPO) and Eurocarers]. First, we will conduct an international comparative analysis of existing classification systems and routinely collected death certificate data on place of death. Secondly, we will conduct a mixed-methods study (ethnography followed by longitudinal quantitative study) in four countries (the Netherlands, Portugal, Uganda and the United States), to compare the preferences and experiences of patients with life-threatening conditions and their families. Thirdly, based on the generated evidence, we will build a contemporary classification of dying places; assess its content validity through focus groups with patients, carers and other stakeholders; and evaluate it in a psychometric study to examine construct validity, reliability, responsiveness, data quality and interpretability. Ethics: Approved by the ethics committee of the University of Coimbra, Faculty of Medicine (CE-068-2022) and committees in each of the participating countries. Discussion: The findings will provide a deeper understanding of the diversity in individual end-of-life pathways. They will enable key developments such as measurement of progress towards achievement of preferences when care can be planned. The project will open new directions in how to care for the dying. Trial registration: Research Registry UIN 9213.

Effects of Al and La elements on mechanical properties of CoNiFe0.6Cr0.6 high-entropy alloys (HEAs) with face-centered cubic (FCC) structure were investigated by first-principles calculations. The variation curves of relevant physical parameters, including lattice constants, formation enthalpy, elastic constants, elastic modulus, Poisson's ratio, Pugh's ratio, Cauchy pressure, anisotropy factors, Vickers hardness, yield strength, and energy factor, as a function of Al and La concentration were discussed in detail. Results show that the resistances to bulk, elastic, and shear deformation decrease with the increase of Al and La concentration. The addition of Al and La can improve the plasticity and ductility of HEAs. Meanwhile, with the increase of Al and La concentration, the metallic characteristic of atomic bonding strengthens and the anisotropy of materials increases. Moreover, the energy factor indicates that the addition of Al and La could promote dislocation nucleation. This study provides a guideline for further research on non-equiatomic CrFeCoNi series HEAs with designed mechanical properties.

Onderzoek naar de rol van familieleden in de besluitvorming over het medisch behandelbeleid van wilsonbekwame patiënten in het verpleeghuis toont aan dat door betrokkenheid van een vertegenwoordiger voor de behandelend arts een grotere verantwoordelijkheid ontstaat. De vertegenwoordiger (meestal een familielid) behoort de belangen van de patiënt te dienen, maar het is aan de arts om te beoordelen of de vertegenwoordiger dat ook daadwerkelijk doet. Dit laat onverlet de professionele verantwoordelijkheid voor het te voeren medische beleid. De betrokkenheid van anderen (verwanten en andere hulpverleners) is van belang voor het antwoord op de vraag ‘Wat is goed voor deze patiënt?’ maar ontneemt artsen niet de verantwoordelijkheid een eigen professionele beslissing te nemen.

An electrostatic hexapole lens is used to manipulate the transverse properties of a beam of barium fluoride molecules from a cryogenic buffer gas source. The spatial distribution of the beam is measured by recording state-selective laser-induced fluorescence on an emccd camera, providing insight into the intensity and transverse position spread of the molecular beam. Although the high mass and unfavorable Stark shift of barium fluoride pose a considerable challenge, the number of molecules in the low-field seeking component of the N = 1 state that pass a 4 mm diameter aperture 712 mm behind the source is increased by a factor of 12. Furthermore, it is demonstrated that the molecular beam can be displaced by up to ±5 mm by moving the hexapole lens. Our measurements agree well with numerical trajectory simulations. We discuss how electrostatic lenses may be used to increase the sensitivity of beam experiments such as the search for the electric dipole moment of the electron.

Recently, we have demonstrated a method to record the longitudinal phase-space distribution of a pulsed cryogenic buffer gas cooled beam of barium fluoride molecules with high resolution. In this paper, we use this method to determine the influence of various source parameters. Besides the expected dependence on temperature and pressure, the forward velocity of the molecules is strongly correlated with the time they exit the cell, revealing the dynamics of the gas inside the cell. Three observations are particularly noteworthy: (1) The velocity of the barium fluoride molecules increases rapidly as a function of time, reaches a maximum 50–200 µ s after the ablation pulse and then decreases exponentially. We attribute this to the buffer gas being heated up by the plume of hot atoms released from the target by the ablation pulse and subsequently being cooled down via conduction to the cell walls. (2) The time constant associated with the exponentially decreasing temperature increases when the source is used for a longer period of time, which we attribute to the formation of a layer of isolating dust on the walls of the cell. By thoroughly cleaning the cell, the time constant is reset to its initial value. (3) The velocity of the molecules at the trailing end of the molecular pulse depends on the length of the cell. For short cells, the velocity is significantly higher than expected from the sudden freeze model. We attribute this to the target remaining warm over the duration of the molecular pulse giving rise to a temperature gradient within the cell. Our observations will help to optimize the source parameters for producing the most intense molecular beam at the target velocity.

The effects of intrinsic and substitutional point defects MX (M = Li, Na, Mg, Al, K, Sc, Tb, Dy, Ho, Er; X = C, Si) and NMX (NM = H, B, N, P, S) on the formation energy, mechanical and thermodynamic properties of 3C-SiC at various temperatures and pressures have been studied based on density functional theory (DFT) with quasi-harmonic approximation (QHA). The results show that the antisite defects are easier to form than the vacancies under various conditions, and MX is usually more difficult to form than NMX. The vacancies and MX defects greatly reduce the Young's modulus E and shear modulus G of 3C-SiC; whereas the antisite and NMX possess little effects. The decrements of E and G of 3C-SiC with NMC and MC are twice as those with NMSi and MSi. The bulk modulus B and Poisson's ratio ν of 3C-SiC are difficult to be varied by defects. These results can be well interpreted by bond characteristics, which is closely related to the Cauchy pressure C12−C44. The defects only slightly change the phonon free energy Fvib, vibrational entropy Svib, constant heat capacity CV, Gibbs free energy G and isobaric heat capacity CP, whereas they have a great influence on the coefficient of thermal expansion αT of 3C-SiC. With the increase of external pressure, the G and CP of all defective compounds increases and decreases linearly, respectively, while the αT presents multiplex variation characteristic.

In this work, the structural stability, fracture toughness, and thermodynamic properties of Co30Ni30Fe20Cr20 high-entropy alloy (HEA) has been investigated by using first-principles calculations combined with special quasi-random structures. The calculated lattice constant of 3.485 Å was in good agreement with the experiments, and the obtained formation enthalpy value of −1.17 eV/atom indicated that this particular HEA was stable. The results showed that the Fracture energy of the [111] direction was much lower than the [001] and [110] directions. Therefore, the bond strength of the [111] direction was inferred to be the weakest. Finally, the entropy, internal energy, and specific heat capacity of the Co30Ni30Fe20Cr20 HEA increased with increasing temperature, while the free energy and bulk modulus decreased. Thus, the results obtained in this work could be used for studying and designing high performance CoCrFeNi HEAs.

The relative energetic stability, mechanical properties, and thermodynamic behavior of B2-AlRE (RE = Sc, Y, La-Lu) second phases in Al alloys have been investigated through the integration of first-principles calculations with the quasi-harmonic approximation (QHA) model. The results demonstrate a linear increase in the calculated equilibrium lattice constant a0 with the ascending atomic number of RE, while the enthalpy of formation ΔHf exhibits more fluctuating variations. The lattice mismatch δ between B2-AlRE and Al matrix is closely correlated with the transferred electron et occurring between Al and RE atoms. Furthermore, the mechanical properties of the B2-AlRE phases are determined. It is observed that the calculated elastic constants Cij, bulk modulus BH, shear modulus GH, and Young's modulus EH initially decrease with increasing atomic number from Sc to Ce and then increase up to Lu. The calculated Cauchy pressure C12-C44, Pugh's ratio B/G, and Poisson's ratio ν for all AlRE particles exhibit a pronounced directional covalent characteristic as well as uniform deformation and ductility. With the rise in temperature, the calculated vibrational entropy (Svib) and heat capacity (CV) of AlRE compounds exhibit a consistent increasing trend, while the Gibbs free energy (F) shows a linear decrease across all temperature ranges. The expansion coefficient (αT) sharply increases within the temperature range of 0~300 K, followed by a slight change, except for Al, AlHo, AlCe, and AlLu, which show a linear increase after 300 K. As the atomic number increases, both Svib and CV increase from Sc to La before stabilizing; however, F initially decreases from Sc to Y before increasing up to La with subsequent stability. All thermodynamic parameters demonstrate similar trends at lower and higher temperatures. This study provides valuable insights for evaluating high-performance aluminum alloys. [ABSTRACT FROM AUTHOR]

Based on first-principles calculations, the effects of substitutional defects of the 3d–5d transition metal elements TMAl on the stability and thermal conductivity of the aluminum matrix were investigated. The results show that with an increase in the atomic number of TM, the defect-forming energy Ef of TMAl exhibits a periodic change feature, which depends on the valence electron configuration of the TM elements. The thermodynamic property parameters calculated with the Debye theory show that the addition of TM atoms does not change the stability of an Al system and can effectively reduce the thermal expansion coefficient of the material. But the equilibrium lattice constant a0 of Al-TMAl supercells changes very little. As the temperature increases, the relaxation time τ decreases, and both the electronic thermal conductivity κe and the total thermal conductivity κ decrease at the temperature range of 100–200 K, followed by a small increase or decrease. Because the lattice thermal conductivity κl is very small in the whole temperature range, the changes in electronic thermal conductivity and total thermal conductivity are basically the same. Moreover, when 1 at.% TM was added at both 300 K and 600 K, it was found that the influence of TM solute atoms on the thermal conductivity κ of Al was much greater than that of the second-phase particles. For solid solution atoms, Pd and Pt atoms have the greatest influence on the thermal conductivity of pure Al. This work is helpful for designing high-performance, heat-resistant Al-based alloys.

The need for journalism educators to critically reflect on social, economic, and technological global changes has been on the agenda since the early 2000s. In this era of disruption, digitalization offers new possibilities by using the internet, its platforms, and its ability to create new forms of training. This piece presents ways in which a new journalism education model can be implemented to better train student journalists.

Atomic diffusion by the vacancy defect of L12-Al3M (M = Sc, Zr, Er, Y) was investigated based on a first-principles calculation. The point defect formation energies were firstly evaluated. Then, the migration energy for different diffusion paths was obtained by the climbing-image nudged elastic band (CI-NEB) method. The results showed that Al atomic and M atomic diffusions through nearest-neighbor jump (NNJ) mediated by Al vacancy (VAl) were, respectively, the preferred diffusion paths in Al3M phases under both Al-rich and M-rich conditions. The other mechanisms, such as six-jump cycle (6JC) and next-nearest-neighbor jump (NNNJ), were energetically inhibited. The order of activation barriers for NNJ(Al-VAl) was Al3Zr < Al3Y < Al3Er < Al3Sc. The Al3Sc phase had high stability with a high self-diffusion activation barrier, while the Al3Zr and Al3Y phases were relatively unstable with a low self-diffusion activation energy. Moreover, the atomic-diffusion behavior between the core and shell layers of L12-Al3M was also further investigated. Zr atoms were prone to diffusion into the Al3Y core layer, resulting in no stable core-shelled Al3(Y,Zr), which well agreed with experimental observation.

High-performance Sc-containing aluminum alloys are limited in their industrial application due to the high cost of Sc elements. Er, Zr, and Y elements are candidates for replacing Sc elements. Combined with the first-principles thermodynamic calculation and the classical nucleation theory, the nucleation of L12-Al3M (M = Sc, Er, Y, Zr) nanophases in dilutealuminum alloys were investigated to reveal their structural stability. The calculated results showed that the critical radius and nucleation energy of the L12-Al3M phases were as follows: Al3Er > Al3Y > Al3Sc > Al3Zr. The Al3Zr phase was the easiest to nucleate in thermodynamics, while the nucleation of the Al3Y and Al3Er phases were relatively difficult in thermodynamics. Various structures of Al3(Y, Zr) phases with the radius r < 1 nm can coexist in Al-Y-Zr alloys. At a precipitate’s radius of 1–10 nanometers, the core–shelled Al3Zr(Y) phase illustrated the highest nucleation energy, while the separated structure Al3Zr/Al3Y obtained the lowest one, and had thermodynamic advantages in the nucleation process. Moreover, the core–shelled Al3Zr(Y) phase obtained a higher nucleation energy than Al3Zr(Sc) and Al3Zr(Er). Core–doubleshelled Al3Zr/Er(Y) obtained a lower nucleation energy than that of Al3Zr(Y) due to the negative ΔGchem of Al3Er and the negative Al3Er/Al3Y interfacial energy, and was preferentially precipitated in thermodynamics stability.

The key parameters of growth and nucleation of Al3TM particles (TM = Sc-Zn, Y-Cd and Hf-Hg) have been calculated using the combination of the first principles calculations with the quasi-harmonic approximation (QHA). Herein, the diffusion rate Ds of TM elements in Al is calculated using the diffusion activation energy Q, and the results show that the Ds of all impurity atoms increases logarithmically with the increase in temperature. With the increase in atomic number of TM, the Ds of 3–5d TM elements decreases linearly from Sc, Y and Hf to Mn, Ru and Ir, and then increases to Zn, Ag and Au, respectively. The interface energy γα/β, strain energy ΔEcs, chemical formation energy variation ΔGV and surface energy Esurave were further computed from the based interface and slab models, respectively. It was found that, with the increase in the atomic number of TM, the interface energies γα/β of Al/Al3TM (TM = (Sc-Zn, Y-Cd)) decreased from Sc and Y to Mn and Tc and then increased to Zn and Cd, respectively (except for the (001) plane of Al/Al3(Fe-Co), the (111) plane of Al/Al3Pd and the (110) and (111) planes of Al/Al3Cd). The strain energies ΔEcs of Al/Al3TM (TM = (Sc-Zn)) increased at first, and then decreased for all cycles. The chemical formation energy ΔGV of all Al3TM changed slightly in the temperature range of 0~1000 K, except that the ΔGV of Al3Sc, Al3Cu, Al3(Y-Zr), Al3Cd, Al3Hf and Al3Hg increased nonlinearly. With the increase in atomic number at both 300 and 600 K, the ΔGV of 3–5d TM elements increased from Sc, Y and Hf to Mn, Tc and Re at first, and then decreased to Co, Rh and Ir, respectively, and slightly changes at the end. With the increase in atomic number of TM, the variation trends of the surface energies of Al3TM intermetallic compounds present similar changes for all cycles, and the (111) surface always has the lowest values.

At room temperature, Al alloys have excellent mechanical properties and are widely used in automotive, electronics, aerospace and other fields, but it is difficult to maintain this advantage in the middle and high temperature ranges. To address this issue, second-phase Al11RE3 (RE represents rare earth element) was introduced into a Al-Mg-RE alloy as its primary constituent. By incorporating RE elements as additives, this material exhibits exceptional mechanical and thermal properties at elevated temperatures. Based on first principles and quasi-harmonic approximation (QHA), the nucleation growth mechanism and surface properties of second-phase Al11RE3 were studied in this paper. The interfacial energy γ α / β , strain energy Δ E CS and chemical driving force Δ G V of Al11RE3 were obtained. Models1, 4, and 6 have better properties of para-site connections than inter-site connections. It is found that the resistances of particle nucleation, interface energy γ α / β and strain energy Δ E CS , first increase and then decrease with increased atomic number REs, but they are much smaller than the chemical driving force Δ G V . A reduced chemical driving force and a diminished nucleation radius R* are more favorable for the process of nucleation. The addition of Sc is the most unfavorable for nucleation, and La has the strongest nucleating ability, which gradually decreases as the atomic number of the lanthanide element increases. The nucleation ability of the Al11RE3 phase decreases with increasing temperature, which is consistent with the experiments. The nucleation radius R* also increases with increasing temperature, indicating that the nucleation ability decreases as the atomic number of the lanthanide elements increases. Since the smaller the nucleation radius R* the easier the nucleation, compared with model4 and 6, model1 has a smaller nucleation radius R* and the smallest increment. Thus, model1 is more prominent in the nucleation mechanism. In the particle growth study, the smaller the diffusion activation energy Q, the faster the diffusion rate in the Al matrix, and hence the higher the coiling rate, which promotes the growth of second-phase particles. The diffusion activation energy Q decreases sequentially from La to Ce and then increases with atomic number. The coarsening rate K LSW of the Al11RE3 phase in models1, 4, and 6 increased with increasing temperature, which promoted the growth of particles. This paper is intended to provide a solid theoretical basis for the production and application of aluminum alloy at high temperatures. [ABSTRACT FROM AUTHOR]

Concurrent genital-anal human papillomavirus (HPV) infections may impose an increased anal cancer risk in women with HPV-related genital lesions. High viral load may facilitate genital-anal HPV concurrence. Genital and anal HPV is reduced by a bivalent HPV16/18 vaccine, yet the effect on concurrent genital-anal HPV remains unclear.This study analyzed viral load in concurrent genital-anal HPV infections, relative to genital-only and anal-only HPV infections and the impact of vaccination in young women. We included 1074 women, who provided both genital and anal swabs. HPV detection and genotyping was performed using the SPF10-DEIA-LiPA25. HPV copy numbers were measured with type-specific qPCRs and corrected for cellular content to obtain the viral load.Concurrent genital-anal HPV often had significantly higher genital viral load (0.09–371 c/cell) than genital-only HPV (3.17E-04-15.9 c/cell, p