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In recent years, slippery surfaces have attracted significant interest due to their excellent liquid-repellent properties and their potential in diverse commercial applications. Such surfaces are prepared by coating functionalized solid substrates with a thin lubricant film that prevents direct contact between a liquid and the substrate. The morphology of thin films upon liquid contact plays a central role in governing various phenomena, including the coalescence and mobility of liquid droplets, heat transfer efficiency, and the extent of lubricant depletion. However, a detailed understanding of film dynamics upon droplet contact remains limited, both from theoretical and experimental perspectives. Here, by employing principles of fluid dynamics, optics, and surface wetting, we present a comprehensive study that examines both the spatial and temporal variations of lubricant films upon contact with sessile liquid droplets and liquid bridges. Our findings reveal that the film dynamics can be categorized into three distinct stages, each significantly influenced by key system parameters: initial film thickness, three-phase contact line width, and Laplace pressure of liquids. Furthermor

Molybdenum disulfide (MoS2) is a widely studied layered material for electronic, optical, and catalytic applications. It can host lithium ions between the van der Waals layers, which triggers a phase transition between the semiconducting 2H phase and metallic 1T phase. While lithium insertion triggers a phase transition to the 1T phase, the phase behavior upon electrochemical lithium removal is not resolved. In this work, we conduct single-flake electrochemical (de)lithiation of MoS2 using microelectrode arrays. Through both electrochemical voltage analysis and correlative Raman spectroscopy, we show that an electrochemically cycled and delithiated MoS2 flake initially remains in the 1T phase. However, over the course of several days, it transitions back into the thermodynamically stable 2H phase. This result resolves the phase transformation pathway upon delithiation and showcases the ability to electrochemically synthesize the metastable 1T-MoS2 phase.

When a firm hires a worker, adding the new hire to payroll is costly. These costs reduce the amount of resources that can go to recruiting workers and amplify how unemployment responds to changes in productivity. Workers also incur up-front costs upon accepting jobs. Examples include moving expenses and regulatory fees. I establish that workers' costs lessen the response of unemployment to productivity changes and do not subtract from resources available for recruitment. The influence of workers' costs is bounded by properties of a matching function, which describes how job openings and unemployment produce hires. Using data on job finding that are adjusted for workers' transitions between employment and unemployment and for how the Job Openings and Labor Turnover Survey records hires, I estimate a bound that ascribes limited influence to workers' costs. The results demonstrate that costs paid by workers upon accepting jobs affect outcomes in the labor market (firms threaten workers with paying the up-front costs again if wage negotiations fail), but their influence on volatility is less important than firms' costs.

The actin cortex is an active biopolymer network underneath the plasma membrane at the periphery of mammalian cells. It is a major regulator of cell shape through the generation of active cortical tension. In addition, the cortex constitutes a mechanical shield that protects the cell during mechanical agitation. Cortical mechanics is tightly controlled by the presence of actin cross-linking proteins, that dynamically bind and unbind actin filaments. Cross-linker actin bonds are weak non-covalent bonds whose bond lifetime is likely affected by mechanical tension in the actin cortex making cortical composition inherently mechanosensitive. Here, we present a quantitative study of changes in cortex composition and turnover dynamics upon short-lived peaks in active and passive mechanical tension in mitotic HeLa cells. Our findings disclose a twofold mechanical reinforcement strategy of the cortex upon tension peaks entailing i) a direct catch-bond mechanosensitivity of cross-linkers filamin and $α$-actinin and ii) an indirect cortical mechanosensitivity that triggers actin cortex reinforcement via enhanced polymerization of actin. We thereby disclose a `molecular safety belt' mechanism

Understanding the role of metal and oxygen in the redox process of layered 3d transition metal oxides is crucial to build high density and stable next generation Li-ion batteries. We combine hard X-ray photoelectron spectroscopy and ab-initio-based cluster model simulations to study the electronic structure of prototypical end-members LiCoO2 and CoO2. The role of cobalt and oxygen in the redox process is analyzed by optimizing the values of d-d electron repulsion and ligand-metal p-d charge transfer to the Co 2p spectra. We clarify the nature of oxidized cobalt ions by highlighting the transition from positive to negative ligand-to-metal charge transfer upon Li+ de-intercalation.

We prove that the integral operators associated with the layer heat potentials depend smoothly upon a parametrization of the support of integration. The analysis is carried out in the optimal Hölder setting.

During the accretion phase of a core-collapse supernovae, large amplitude turbulence is generated by the combination of the standing accretion shock instability and convection driven by neutrino heating. The turbulence directly affects the dynamics of the explosion, but there is also the possibility of an additional, indirect, feedback mechanism due to the effect turbulence can have upon neutrino flavor evolution and thus the neutrino heating. In this paper we consider the effect of turbulence during the accretion phase upon neutrino evolution, both numerically and analytically. Adopting representative supernova profiles taken from the accretion phase of a supernova simulation, we find the numerical calculations exhibit no effect from turbulence. We explain this absence using two analytic descriptions: the Stimulated Transition model and the Distorted Phase Effect model. In the Stimulated Transition model turbulence effects depend upon six different lengthscales, and three criteria must be satisfied between them if one is to observe a change in the flavor evolution due to Stimulated Transition. We further demonstrate that the Distorted Phase Effect depends upon the presence of mult

The premise of this paper is to explore the potential of reminiscing in facilitating self soothing. The research presented looks at people's activities on Facebook and whether these particular activities impact upon their perceived sense of wellbeing, furthermore, whether specific Facebook activities enable a self-soothing effect when feeling low in mood. A survey was distributed amongst Facebook users. The results from the study appear to indicate that in comparison to other Facebook activities, looking back upon photos and wall posts in particular, could have a positive impact upon wellbeing. Additionally, the results indicate that people who have mental health problems, experience a more positive impact upon their wellbeing when looking at photos and wall posts, than those who did not have a history of mental health issues. The results from the research presented here contribute towards the viability of developing a mobile application to facilitate positive reminiscing

The ultrathin nature and dangling bonds free surface of two-dimensional (2D) semiconductors allow for significant modifications of their band gap through strain engineering. Here, thin InSe photodetector devices are biaxially stretched, finding, a strong band gap tunability upon strain. The applied biaxial strain is controlled through the substrate expansion upon temperature increase and the effective strain transfer from the substrate to the thin InSe is confirmed by Raman spectroscopy. The band gap change upon biaxial strain is determined through photoluminescence measurements, finding a gauge factor of up to ~200 meV/%. We further characterize the effect of biaxial strain on the electrical properties of the InSe devices. In the dark state, a large increase of the current is observed upon applied strain which gives a piezoresistive gauge factor value of ~450-1000, ~5-12 times larger than that of other 2D materials and of state-of-the-art silicon strain gauges. Moreover, the biaxial strain tuning of the InSe band gap also translates in a strain-induced redshift of the spectral response of our InSe photodetectors with ΔEcut-off ~173 meV at a rate of ~360 meV/% of strain, indicating

In this paper, we investigate the impact of the electromagnetic scattering caused by other objects in nonfree space on the time averaged force exerted upon a Rayleigh particle, which is conventionally referred to as the backaction effect. We show that backaction modifies the gradient force, radiation pressure, and spin curl force exerted upon Rayleigh particles, and gives rise to an additional force term which stems from the gradient of the backaction field in nonfree space. As a numerical example, we look into the trapping of a dielectric nanoparticle at the center of curvature of a spherical mirror, and study how it is affected by the backaction effect. We show that backaction can enhance the force exerted upon the particle, reshape the trapping potential, and shift the equilibrium position of the particle.

Evolution of structure of spherical SiO2 nanoparticles upon cooling from the melt has been investigated via molecular-dynamics (MD) simulations under non-periodic boundary conditions (NPBC). We use the pair interatomic potentials which have weak Coulomb interaction and Morse type short-range interaction. The change in structure of SiO2 nanoparticles upon cooling process has been studied through the partial radial distribution functions (PRDFs), coordination number and bond-angle distributions at different temperatures. The core and surface structures of nanoparticles have been studied in details. Our results show significant temperature dependence of structure of nanoparticles. Moreover, temperature dependence of concentration of structural defects in nanoparticles upon cooling from the melt toward glassy state has been found and discussed.

We report on the experimental observation of selective delamination of semi-transparent materials on the example of yttria-stabilized zirconia ceramics upon femtosecond laser processing of its surface with low numerical aperture lens. The delamination of a ceramic layer of dozens of micrometers takes place as a by-side effect of surface processing and is observed above the surface ablation threshold. The onset of delamination (delamination threshold) depends on the degree of overlap of the irradiation spots from consecutive laser pulses upon beam scanning over material surface. Analysis of the delaminated layer indicates that the material undergoes melting on its both surfaces. The mechanism of delamination is identified as a complex interplay between the optical response of laser-generated free-electron plasma and nonlinear effects upon laser beam propagation in semi-transparent ceramics. The discovered effect enables controllable laser microslicing of brittle ceramic materials.

Accurately determining a change in protein binding affinity upon mutations is important for the discovery and design of novel therapeutics and to assist mutagenesis studies. Determination of change in binding affinity upon mutations requires sophisticated, expensive, and time-consuming wet-lab experiments that can be aided with computational methods. Most of the computational prediction techniques require protein structures that limit their applicability to protein complexes with known structures. In this work, we explore the sequence-based prediction of change in protein binding affinity upon mutation. We have used protein sequence information instead of protein structures along with machine learning techniques to accurately predict the change in protein binding affinity upon mutation. Our proposed sequence-based novel change in protein binding affinity predictor called PANDA gives better accuracy than existing methods over the same validation set as well as on an external independent test dataset. On an external test dataset, our proposed method gives a maximum Pearson correlation coefficient of 0.52 in comparison to the state-of-the-art existing protein structure-based method ca

Magnetic charge propagation in bulk frustrated materials has yielded a paradigm-shift in science, allowing the symmetry between electricity and magnetism to be studied. Recent work is now suggesting magnetic charge dynamics upon the spin-ice surface may have important implications in determining the ordering and associated phase space. Here we detail a 3D artificial spin-ice, a 3D nanostructured array of magnetic islands which captures the exact geometry of bulk systems, allowing field-driven dynamics of magnetic charge to be directly visualized upon the surface. Using magnetic microscopy, we observe vastly different magnetic charge dynamics along two principle directions. These striking differences are found to be due to the surface-termination and associated coordination which yields different energetics and interaction strengths for magnetic charges upon the surface.

We investigate positron scattering upon endohedrals and compare it with electron-endohedral scattering. We show that the polarization of the fullerene shell considerably alters the polarization potential of an atom, stuffed inside a fullerene. This essentially affects both the positron and electron elastic scattering phases as well as corresponding cross-sections. Of great importance is also the interaction between the incoming positron and the target electrons that leads to formation the virtual positronium. We illustrate the general trend by concrete examples of positron and electron scattering upon endohedrals He@C60 and Ar@C60, and compare it to scattering upon fullerene C60. To obtain the presented results, we have employed new simplified approaches that permit to incorporate the effect of fullerenes polarizability into the He@C60 and Ar@C60 polarization potential and to take into account the virtual positronium formation. Using these approaches, we obtained numeric results that show strong variations in shape and magnitudes of scattering phases and cross-sections due to effect of endohedral polarization and virtual positronium formation.

When an electron is scattered by a tightly-focused laser beam in vacuum, the intensity gradient is a critical factor to influence the electron dynamics, for example, the electron energy exchange with the laser fields as have been explored before [P.X.Wang et al.,J. Appl. Phys. 91, 856 (2002]. In this paper, we have further investigated its influence upon the electron high-harmonic generation (HHG) by treating the spacial gradient of the laser intensity as a ponderomotive potential. Based upon perturbative QED calculations, it has been found that the main effect of the intensity gradient is the broadening of the originally line HHG spectra. A one-to-one relationship can be built between the beam width and the corresponding line width. Hence this finding may provides us a promising way to measure the beam width of intense lasers in experiments. In addition, for a laser pulse, we have also studied the different influences from transverse and longitudinal intensity gradients upon HHG.

The presented letters covers an almost year-long discussion of the author and a Very Qualified scientist, VQS, about the dependence of mass upon speed if relativistic corrections are taken into account. VQS believes that since mass is a scalar, it cannot depend upon speed and has to be the same in all inertial coordinate frames. In his view, the very idea of speed dependence of the mass of a particle or a body is incorrect and misleading. As such, the notion of speed dependence of a particle mass has to be eliminated from textbooks on physics and from teaching of this subject. The author claims that this notion has the right to exist, is easily understandable and convenient for most of the students, both non physicists and even physicist. His view is that it is nothing wrong in expressions like particle mass increases with the growth of speed. His view upon the debate is that both approaches are equally correct. His view is that the dilemma depends or not depends is a matter of taste and convenience, not of scientific importance and unavoidable scientific rigor. Upon request of VQS, M. Amusia has commented the manuscript of academician L. B. Okun resent book ABC of physics. The com

We study the confinement scenario in N=2 supersymmetric SU(2) gauge theory near the monopole point upon breaking of N=2 supersymmetry by the adjoint matter mass term. We confirm claims made previously that the Abrikosov-Nielsen-Olesen string near the monopole point fails to be a BPS state once next-to-leading corrections in the adjoint mass parameter taken into account. Our results shows that type I superconductivity arises upon monopole condensation. This conclusion allows us to make qualitative predictions on the structure of the hadron mass spectrum near the monopole point.

The memory effect upon glassification is studied in the glass to rubber transition of vulcanized rubber with the strain as a controlling parameter. A phenomenological model is proposed taking the history of the temperature and the strain into account, by which the experimental results are interpreted. The data and the model demonstrate that the glassy state memorizes the time-course of strain upon glassification, not as a single parameter but as the history itself. The data also show that the effect of irreversible deformation in the glassy state is beyond the scope of the present model. Authors' remark: The title of the paper in the accepted version is above. The title appeared in PRL is the one changed by a Senior Assistant Editor after acceptance of the paper. The recovery of the title was rejected in the correction process.