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Neandertal predation agenda reveals seasonal strategies during MIS 5–4 transition in Axlor, northatlantic Iberia
Structural prediction and surface-induced short-range order in HfNbTaZr high-entropy alloy nanoparticles
High entropy alloy (HEA) nanoparticles (NPs), finite-size nanostructures that combine multiple elements coexistent with a nanoscale surface, have emerged as a new material due to their non-trivial properties. While there exist several studies addressing the behavior of body-centered cubic (BCC) HEAs, there is still missing information devoted to predicting the structural and morphological configurations that HEA NPs can adopt. In this work, using molecular dynamic simulations and Monte Carlo algorithms, HfNbTaZr HEA NPs of 2 and 3 nm were studied. For all simulated scenarios, HEA NPs showed a significant precipitation of elements while maintaining their BCC crystalline structure. The presence of the surface drives the diffusion of some elements, leading to the formation of a core-shell structure with an HfZr rich shell and a near equiatomic HEA core. A topological change in the typical short-range order of HfNbTaZr is induced by the surface, since the formation of HfZr bands is replaced by the formation of an HfZr rich surface. It was observed that BCC HEA NPs have an irregular shear stress, a consequence of the chemical complexity, which at the same time induces surface reconstruction favoring the formation of highly faceted nanoparticles. The {111} planes were identified as the most probable surface facets on the NP, mostly due to the enthalpy of mixing and cohesive energy. Finally, a phase separation of the Hf and Zr surfaces is observed, which is also in accordance with the positive enthalpy of mixing that favors the repulsion between both elements.
Research on an efficient prediction for deformations of thread connections based on deep transfer learning
Dielectric properties of zwitterionic liquids
The dielectric properties of a series of zwitterionic liquids are thoroughly examined in both the solution and melt states. In dilute solutions, the molar dielectric increment and subsequently derived dipole moment of zwitterionic liquids correlate strongly with the number of linker atoms between the ion pair, following the same trend as previously extensively studied zwitterionic solids. Further analysis indicates that the linker does not adopt a fully extended conformation but is slightly coiled. Despite its high dipole moment, the dielectric relaxation of zwitterionic liquids in the melt state resembles that of ordinary glass-forming dipolar liquids and consists of a primary α-relaxation and a high-frequency “excess wing.” The relaxation strengths of these two processes are proportional to 1/T and −1/T, respectively. On the other hand, while the α-peak broadens on the high-frequency side upon a decrease in temperature, no universal trend has been found for the low-frequency dispersion. The unexpectedly high conductivity in zwitterionic liquids appears to stem from the presence of ionic impurities rather than the “polarization current” associated with dipole rotation. Decoupling analysis shows that the dc conduction is not fully slaved to the α-relaxation and exhibits substantially weaker temperature dependence, lending support to the aforementioned argument regarding the origin of dc conductivity. Finally, the glass transition temperature of zwitterionic liquids examined in this work shows a weak negative correlation with their molecular weight, deviating from the general trend observed for ordinary dipolar liquids, whereas the fragility index increases with increasing relative polarization volume.
Multiparity induces persistent myocardial structural, functional and transcriptomic remodelling in mice
Abstract Pregnancy poses unique hemodynamic and metabolic demands on the heart. Recent data suggests that a history of multiple pregnancies may be associated with a late-term increased risk of heart failure with preserved ejection fraction (HFpEF), however, the mechanistic basis is unknown. We postulated that the repetitive biological and hemodynamic impact of multiple pregnancies could cause persistent myocardial remodelling providing a substrate for subsequent HFpEF. Multiparous (MP) mice (C57Bl/6J) aged 24 months were compared to age-matched non-parous (NP) mice (n = 8) in a blinded analysis. We evaluated blood pressure, body composition, gross weight and histologic cardiac structure. Cardiac function was assessed by echocardiography together with transcriptomic analysis of the left ventricular myocardium. At 15 months post oestrous cycle disruption, MP mice continued to demonstrate a constellation of myocardial alterations including higher heart to tibial length ratio (P < 0.05), body weight (P < 0.01), and fat mass (P < 0.01) compared to NP mice. MP mice had increased isovolumetric relaxation time (P < 0.01), increased end-diastolic (P < 0.05) and systolic volumes (P < 0.005), and mildly reduced left ventricular ejection fractions (LVEF) (P < 0.005) compared to non-parous mice. This was accompanied by marked elevations in mRNA levels of cardiac markers; Myh6 (P < 0.01) and Nppa (P < 0.01). mRNA levels of Il18 (P < 0.05) and the basal extracellular matrix protein–fibronectin (P < 0.05) were also increased, with a significant increase in interstitial fibrosis (P < 0.05). Bulk RNA sequencing (RNA Seq) further revealed persistent differential expression of 128 genes with over/under-represented pathways involved in extracellular matrix (ECM) regulation and organic anion/ion transport, respectively. Multiparity alters cardiac gene profile and causes myocardial remodelling that persists into later life, providing a potential foundation for the HF phenotypes such as HFpEF. Further studies are required to investigate the nature of the interaction between pregnancy-associated remodelling and other factors known to be associated with HFpEF development.
Comment on “Observations and analysis with the spline-based Rydberg–Klein–Rees approach for the 31Σg+ state of Rb2” [J. Chem. Phys. 144, 024308 (2016)]
Retraction Note: A combined microfluidic deep learning approach for lung cancer cell high throughput screening toward automatic cancer screening applications
Jahn–Teller coupling effects on the lowest energy photoelectron spectrum of adamantane: A theoretical investigation
An ab initio quantum dynamics study has been performed here to examine the complex nuclear motions underlying the highly diffuse and irregular vibronic structure of the first photoelectron band of adamantane (Ada). Associated potential energy surfaces of the triply degenerate ground electronic manifold of the adamantane radical cation, subject to T2 ⊗ (e + t2) Jahn–Teller (JT) effect, are established via extensive electronic structure calculations. Subsequently, the nuclear motions on these JT coupled electronic sheets are investigated via wave packet propagations. The theoretical results are in good agreement with the experimental measurements. Larger JT stabilization energy due to T2 ⊗ t2 distortions, compared to T2 ⊗ e distortions, illustrates the dominating role of t2 modes in the symmetry breaking of the initial Td nuclear configuration of adamantane radical cation. The JT effect is also found to play a central role on the highly diffuse, broad, and complex first photoelectron band of Ada. In particular, t2 symmetric ν25 mode (C–C stretching + C–H bending motion) is found to be the origin of the high energy satellite peaks, as well as dominates the vibrational progression underlying the whole band. While the vibrational assignments of some of the major vibronic peaks agree with the available results, renewed assignments are suggested for the remaining peaks.
A universal color curve for roasted arabica coffee
Abstract Color is a key indicator of quality and roast level in coffee beans. Surprisingly, little is known about the effect of different “roast profiles,” i.e., the temperature versus time inside the roaster, on the dynamics of color during roasting, with most prior work focused on laboratory-scale roasters with little control over the roast profile. Here, we investigate seven roast profiles of the same total duration but varying dynamics inside a 5 kg commercial drum roaster, using coffee from three origins. We show that despite the dramatic differences in roast profiles and coffee origins, the bean color always maps onto a “universal roasted coffee color curve” when plotted in the L*a*b* color space. This universal color curve was modeled using polynomial mixed-effects regression and validated through a systematic review of existing literature following the PRISMA protocol to demonstrate its broad applicability. Although the dynamics of roast color development varied with roast profiles, the coffees always had approximately the same L*a*b* values at significant roast milestones, including color change, first crack, and second crack. We discuss how these results provide insight into color measurements and how they can quantitatively inform roast-level standards in the coffee industry for both real-time and post-roast applications.
The impact of ground losses on estimations of lightning-induced voltage with dispersive soil parameters
Abstract In areas with frequent lightning activity, studying lightning induced voltage on overhead distribution lines is crucial to improve the line performance under nearby lightning strikes. This article studies the impact of ground losses in the transmission line model on lighting-induced voltage using an analytical approach. The soil characteristics was represented using fixed and frequency dependent soil models. Firstly, the lightning electromagnetic fields have been computed considering the influence of finite ground conductivity using Cooray-Rubinstein model. Afterwards, the lightning-induced voltage has been computed using Agrawal coupling model in frequency domain. The results show that incorporating ground losses in the transmission line model has a considerable effect on lightning-induced voltages at different velocities. The influence of velocity was evaluated at: 40 m/μs, 120 m/μs, and 200 m/μs respectively. It was found that the influence of ground losses on the peak value of LIVs is more significant at 40 m/μs. Since the median value of lightning velocities is 120 m/μs, it is deduced that the influence of ground losses is more pronounced at lower velocities as it causes an increase in the magnitude of lightning-induced voltage. The effect of incorporating ground losses in the transmission line model on lightning-induced voltage is also evaluated at various values of transmission line height. The effect of transmission line height was examined at 6 m and 10 m respectively. It was found that the effect of ground losses is greater at the height of 10 m at the midpoint of the transmission line. Consequently, as the height of the transmission line decreases, the influence of ground losses also decreases. However, the opposite occurs at positions far from the midpoint, where the influence of ground losses increases with lower transmission line heights. The impact of incorporating ground losses in the transmission line model on lightning-induced voltage is examined at different distances between the lightning channel and the transmission line. The effect of these distances was examined at values of 50 m and 100 m respectively. It was found that the influence of ground losses diminishes at distances of 100 m and above. Furthermore, lightning induced voltage magnitude with frequency dependent soil model is lower than with fixed soil model.
Optimization of glass debris in the treatment of swelling clay soils using recycled materials for sustainable road engineering
Study on elongation master curve of thermal aging composite modified double base propellant
Impacts of pollution on coral bacterial and metabolites diversity across Dapeng Cove of South China sea
Investigating social exclusion, affect and emotion regulation in young people using the ostracism online paradigm
Abstract Social exclusion significantly affects adolescents’ well-being. Previous research has indicated that factors such as rejection sensitivity, internalizing disorders and dysfunctional emotion regulation can amplify the emotional impact of ostracism, whereas strategies such as acceptance may alleviate it. This study explores affect changes induced by the Ostracism Online paradigm, and examines the roles of rejection sensitivity, emotion regulation and internalizing symptoms in N = 73 young people (aged 14–21). The participants were randomly assigned to the experimental and control groups to test whether trained acceptance could support recovery from ostracism. As hypothesized, the results revealed worsened positive and negative affect following ostracism. Other than predicted, rejection sensitivity and internalizing symptoms did not significantly influence these changes. Contrary to expectations, acceptance did not facilitate recovery. The time x group interaction did not reach significance after correction, and post hoc tests did not reveal significant differences. As hypothesized, internalizing symptoms were linked to emotion regulation and rejection sensitivity. These findings contribute to understanding the psychological impact of ostracism, emphasizing the importance of considering mental health in future research, along with the study’s limitations.