Evolution Of Profile Research Articles

Temporal evolution of demarcations between the unsteady and steady regions and between the film and meniscus during dip coating with vertical withdrawal of Newtonian fluids

Thus far studies on dip coating focus on the asymptotic layer thickness which is reached only in the lower part of the layer when the withdrawal time is sufficiently long. This work attempts to offer a complete description of the evolution of layer thickness profile with withdrawal time for vertical withdrawal of Newtonian fluids using simulation and the Buckingham π theorem. The results show that over time, the withdrawal process successively undergoes two regimes: (I) an unsteady film region and an unsteady meniscus region and (II) an unsteady film region connected to a steady meniscus region through an unsteady meniscus region. The controlling factors for the two regimes are identified at different values of capillary number and Reynolds number. Models are proposed to predict the heights of the demarcations between different regions. The models agree well with experimental results when the controlling forces are viscous force and gravity.

Exocyclic DNA adducts and oxidative stress parameters: useful tools for biomonitoring exposure to aldehydes in smokers

Exocyclic DNA adducts have been shown to be potential biomarkers of cancer risk related to oxidative stress and exposure to aldehydes in smokers. In fact, aldehydes potentially arise from tobacco combustion directly and endogenously through lipid peroxidation. This study aims to investigate the relationship between a profile of nine aldehydes-induced DNA adducts and antioxidant activities, in order to evaluate new biomarkers of systemic exposure to aldehydes. Using our previously published UPLC-MS/MS method, adducts levels were quantified in the blood DNA of 34 active smokers. The levels of antioxidant vitamins (A, C and E), coenzyme Q10, β-carotene, superoxide dismutase (SOD) and autoantibodies against oxidized low-density lipoprotein were measured. Adducts induced by tobacco smoking-related aldehydes were quantified at levels reflecting an oxidative production from lipid peroxidation. A significant correlation between SOD and crotonaldehyde-induced adducts (p = 0.0251) was also observed. β-carotene was negatively correlated with adducts of formaldehyde (p = 0.0351) and acetaldehyde (p = 0.0413). Vitamin C tended to inversely correlate with acetaldehyde-induced adducts (p = 0.0584). These results are promising, and the study is now being conducted on larger cohort with the aim of evaluating the impact of smoking cessation programs on the evolution of adducts profile and antioxidants activities.

A Non-Destructive Study of Optical, Geometric and Luminescent Parameters of Active Optical Fibers Preforms

This work is devoted to the scientific and technical aspects of individual stages of active optical fibers preforms’ optical-geometric parameters metrological control. The concept of a system presented makes it possible to carry out a study of a rare earth element distribution in the preform of an active optical fiber and to monitor geometric parameters, and also to study the evolution of the refractive index profile along the length of the sample at a qualitative level. As far as it is known, it is the first description of the preform optical, geometric, and luminescent properties measurement within a single automated laboratory bench. Also, the novelty of the approach lies in the fact that the study of the refractive index profile variation along the length of the preform is, for the first time, conducted using the “dry” method, that is, without immersing the sample in synthetic oil, which makes the process less labor-intensive and safer.

Neural longitudinal mapping of multidimensional performance profiles of Latin American universities

Objective. To introduce an artificial intelligence method and to use it to analyze the evolution of the multidimensional performance profiles of the most prominent Latin American universities, according to the Times Higher Education Latin America University Rankings.
 Design/Methodology/Approach. To multidimensionally characterize universities' performance profiles, we use the rankings' sub-scores indicators, which quantify five dimensions of academic endeavor assessed by this ranking. To automatically compare and visually analyze performance profile's evolution our method uses an artificial neural network.
 Results/Discussion. The neurocomputational procedure allowed us to discover all the characteristic performance profiles of the 50 best ranked universities (20 institutional profiles in 2019), and to visualize, in a knowledge map, the universities' groups sharing similar profiles. Furthermore, the profile's evolution of this group of universities was analyzed, and visually displayed in a sequence of knowledge maps, covering the four years period 2016-2019. In general, these universities show a remarkable improvement in Teaching, Research and Citation scores during 2016-2019. The profiles diversity of the best ranked universities, and the predominance and homogenization process of Brazilian universities profiles are noteworthy.
 Conclusions. Performance profile characterization using multiple indicators is a matter of interest in diverse domains. However, visualization or comparison of multidimensional performance profiles is not an easy task for the human mind. Even more challenging is the visual analysis of multidimensional performance profiles evolution. The neuro-longitudinal technique introduced is a useful tool to analyze and visualize the evolution of multidimensional performance profiles.
 Originality/Value. The approach and techniques introduced in the paper have an important degree of generality and can be used to analyze other type of rankings or multidimensional data.

Cultivable microbial diversity, peptide profiles, and bio-functional properties in Parmigiano Reggiano cheese.

Lactic acid bacteria (LAB) communities shape the sensorial and functional properties of artisanal hard-cooked and long-ripened cheeses made with raw bovine milk like Parmigiano Reggiano (PR) cheese. While patterns of microbial evolution have been well studied in PR cheese, there is a lack of information about how this microbial diversity affects the metabolic and functional properties of PR cheese. To fill this information gap, we characterized the cultivable fraction of natural whey starter (NWS) and PR cheeses at different ripening times, both at the species and strain level, and investigated the possible correlation between microbial composition and the evolution of peptide profiles over cheese ripening. The results showed that NWS was a complex community of several biotypes belonging to a few species, namely, Streptococcus thermophilus, Lactobacillus helveticus, and Lactobacillus delbrueckii subsp. lactis. A new species-specific PCR assay was successful in discriminating the cheese-associated species Lacticaseibacillus casei, Lacticaseibacillus paracasei, Lacticaseibacillus rhamnosus, and Lacticaseibacillus zeae. Based on the resolved patterns of species and biotype distribution, Lcb. paracasei and Lcb. zeae were most frequently isolated after 24 and 30 months of ripening, while the number of biotypes was inversely related to the ripening time. Peptidomics analysis revealed more than 520 peptides in cheese samples. To the best of our knowledge, this is the most comprehensive survey of peptides in PR cheese. Most of them were from β-caseins, which represent the best substrate for LAB cell-envelope proteases. The abundance of peptides from β-casein 38-88 region continuously increased during ripening. Remarkably, this region contains precursors for the anti-hypertensive lactotripeptides VPP and IPP, as well as for β-casomorphins. We found that the ripening time strongly affects bioactive peptide profiles and that the occurrence of Lcb. zeae species is positively linked to the incidence of eight anti-hypertensive peptides. This result highlighted how the presence of specific LAB species is likely a pivotal factor in determining PR functional properties.

Introducing the concept of generalized thermal diffusivity to understand coupled heat–charge transport in ionic solutions

A theoretical framework addressing the coupled thermal and charge transport phenomena in ionic solutions is here developed. Starting from the microscopic definitions of thermal and charge currents from Onsager formulation of non-equilibrium thermodynamics, a unique, very general and compact form of the governing differential equation for the evolution of a temperature profile is derived. In particular, the concept of generalized thermal diffusivity is introduced to capture the overall effect of the coupling between heat and charge transport in a single phenomenological coefficient as well as to shed light on the non-equivalent situations of concurrent or discordant heat and charge currents. To validate our theoretical framework, an ionic salt solution of NaCl in water is investigated.

The combined effects of tide and storm waves on beach profile evolution

Meso- to macro-tidal beaches are extensively distributed around the world. Water level determines the location where wave action can reach. Tide induced water level changes are the main component of total water level during typhoon landfall, which determines the extent and degree of beach erosion. Considering the tidal level wave height variation process in physical model experiments is crucial for the evaluation of beach erosion. This study presents the results of a new set of beach profile evolution process which considers the combined effects of tide and storm waves. Compared with the mean tidal level situation, tide induced water level variations significantly changes the erosion pattern of profile. The maximum erosion magnitude decreases by about 60% and the horizontal range increases by about 25%.

Plasma-infused solitary waves: Unraveling novel dynamics with the Camassa–Holm equation

This investigation employs advanced computational techniques to ascertain novel and precise solitary wave solutions of the Camassa–Holm ([Formula: see text]) equation, a partial differential equation governing wave phenomena in one-dimensional media. Originally designed for the representation of shallow water waves, the [Formula: see text] equation has exhibited versatility across various disciplines, including nonlinear optics and elasticity theory. It intricately delineates the interplay between nonlinear and dispersive effects in wave systems, with nonlinearity arising from component interactions and dispersion rooted in the temporal spreading of waves. Furthermore, the [Formula: see text] equation governs the spatiotemporal evolution of wave profiles, encompassing both nonlinear and dispersive influences. Notably, the equation allows for soliton solutions — localized wave packets sustaining their form over extended distances. The identification of precise solitary wave solutions holds paramount significance for comprehending the [Formula: see text] equation’s behavior in diverse physical contexts, such as fluid dynamics and nonlinear optics. Moreover, this study establishes a correlation between the investigated model and plasma physics, demonstrating the efficacy and efficiency of the employed computational techniques through benchmarking against alternative computational methods. This augmentation underscores the broader relevance of the [Formula: see text] equation, extending its applicability to provide insights into wave phenomena analogous to those encountered in plasma physics.

Cosmological and idealized simulations of dark matter haloes with velocity-dependent, rare and frequent self-interactions

ABSTRACT Dark matter self-interactions may have the capability to solve or at least mitigate small-scale problems of the cosmological standard model, Lambda cold dark matter. There are a variety of self-interacting dark matter models that lead to distinguishable astrophysical predictions and hence varying success in explaining observations. Studies of dark matter (DM) density cores on various mass scales suggest a velocity-dependent scattering cross-section. In this work, we investigate how a velocity dependence alters the evolution of the DM distribution for frequent DM scatterings and compare to the velocity-independent case. We demonstrate that these cases are qualitatively different using a test problem. Moreover, we study the evolution of the density profile of idealized DM haloes and find that a velocity dependence can lead to larger core sizes and different time-scales of core formation and core collapse. In cosmological simulations, we investigate the effect of velocity-dependent self-interaction on haloes and satellites in the mass range of ≈1011–$10^{14} \, \mathrm{M_\odot }$. We study the abundance of satellites, density, and shape profiles and try to infer qualitative differences between velocity-dependent and velocity-independent scatterings as well as between frequent and rare self-interactions. We find that a strongly velocity-dependent cross-section can significantly amplify the diversity of rotation curves, independent of the angular dependence of the differential cross-section. We further find that the abundance of satellites in general depends on both the velocity dependence and the scattering angle, although the latter is less important for strongly velocity-dependent cross-sections.

On learning latent dynamics of the AUG plasma state

In this work, we demonstrate the utility of state representation learning applied to modeling the time evolution of electron density and temperature profiles at ASDEX-Upgrade (AUG). The proposed model is a deep neural network, which learns to map the high dimensional profile observations to a lower dimensional state. The mapped states, alongside the original profile's corresponding machine parameters, are used to learn a forward model to propagate the state in time. We show that this approach is able to predict AUG discharges using only a selected set of machine parameters. The state is then further conditioned to encode information about the confinement regime, which yields a simple baseline linear classifier, while still retaining the information needed to predict the evolution of profiles. We, then, discuss the potential use cases and limitations of state representation learning algorithms applied to fusion devices.

Simulation of the time-dependent propagation of leak-triggered helium density gradients in cryogenic and nonisothermal accelerator vacuum systems

A novel simulation code for the calculation of the time-dependent evolution of helium density profiles in tubular-shaped beam vacuum systems of particle accelerators is presented. The code called TransVac was written in the statistics programming language R using the noncommercial development software RStudio and is based on an analytical approach. In contrast to earlier simulation tools based on analytical computational methods, the new code does not only master the profile calculation in conventional vacuum systems operated at room temperature, but also in fully cryogenic and in nonisothermal systems composed of cryogenic and warm sections. Data of helium adsorption isotherms are used to calculate gas densities profiles in cold vacuum systems with the cryosorption-based wall-pumping effect. The article discusses how the simulation code works and which mathematical algorithm is used. Comparisons between experimental and theoretical data confirm that the software developed provides sufficiently reliable predictions on the propagation behavior of leak-triggered helium pressure waves in cryogenic and room-temperature vacuum systems as well.

Exploring the Gas-phase Metallicity Gradients of Star-forming Galaxies at Cosmic Noon

We explore the relationships between the [O/H] gas-phase metallicity radial gradients and multiple galaxy properties for 238 star-forming galaxies at 0.6 < z < 2.6 selected from the CANDELS Lyα Emission at Reionization survey with stellar mass 8.5<logM*/M⊙<10.5 . The gradients cover the range from −0.11 to 0.22 dex kpc−1, with the median value close to 0. We reconstruct the nonparametric star formation histories (SFHs) of the galaxies with spectral energy distribution modeling using Prospector with more than 40 photometric bands from the Hubble Space Telescope, Spitzer, and ground-based facilities. In general, we find weak or no correlations between the metallicity gradients and most galaxy properties, including the mass-weighted age, recent star formation rate, dust attenuation, and morphology as quantified by both parametric and nonparametric diagnostics. We find a significant but moderate correlation between the gradients and the “evolutionary time,” a temporal metric that characterizes the evolutionary status of a galaxy, with flatter gradients observed in more evolved galaxies. Also, there is evidence that galaxies with multiple star formation episodes in their SFHs tend to develop more negative gas-phase metallicity gradients (higher [O/H] at the center). We conclude that gas kinematics, e.g., radial inflows and outflows, is likely an important process in setting the gas-phase metallicity gradients, in addition to the evolution of the SFH radial profile. Since the gradients are largely independent of the galaxies’ physical properties and only weakly dependent on their SFH, it would appear that the timescale of the gas kinematics is significantly shorter than the evolution of star formation.

The AO327 Drift Survey Catalog and Data Release of Pulsar Detections

The AO327 drift survey for radio pulsars and transients used the Arecibo telescope from 2010 until its collapse in 2020. AO327 collected ∼3100 hr of data at 327 MHz with a time resolution of 82 μs and a frequency resolution of 24 kHz. While the main motivation for such surveys is the discovery of new pulsars and new, even unforeseen, types of radio transients, they also serendipitously collect a wealth of data on known pulsars. We present an electronic catalog of data and data products of 206 pulsars whose periodic emission was detected by AO327 and are listed in the Australia Telescope National Facility catalog of all published pulsars. The AO327 data products include dedispersed time series at full time resolution, average (“folded”) pulse profiles, Gaussian pulse profile templates, and an absolute phase reference that allows phase aligning the AO327 pulse profiles in a physically meaningful manner with profiles from data taken with other instruments. We also provide machine-readable tables with uncalibrated flux measurements at 327 MHz and pulse widths at 50% and 10% of the pulse peak determined from the fitted Gaussian profile templates. The AO327 catalog data set can be used in applications like population analysis of radio pulsars, pulse profile evolution studies in time and frequency, cone and core emission of the pulsar beam, scintillation, pulse intensity distributions, and others. It also constitutes a ready-made resource for teaching signal-processing and pulsar astronomy techniques.

Brave New World: Navigating New Paradigms in the Educational Landscape for the Evolving Learner in a Rapidly Changing Era

This literature review explores the significant transformations in the educational landscape prompted by technological advancements and changing learner profiles in the digital era. The review examines the evolution of learner profiles, highlighting the shift towards multisensory learning, digital fluency, and a preference for interactive, personalized learning experiences. It delves into integrating innovative technologies such as virtual reality (VR), augmented reality (AR), and blockchain in education and discusses their implications for teaching and learning. The review also considers the impact of neuroscience on educational practices, emphasizing the importance of understanding brain functioning and neuroplasticity in developing effective teaching strategies. The unprecedented shift to online and blended learning models, accelerated by the COVID-19 pandemic, is analyzed for its long-term effects on educational delivery and pedagogy. Additionally, the review addresses the growing emphasis on interdisciplinary learning, sustainability, mental health, and well-being within educational curricula. The implications of these transformative trends for educators, policymakers, and learners are discussed, highlighting the need for adaptive and responsive approaches to education in the face of rapid technological and societal changes. The review concludes with reflections on the future trajectory of education, anticipating continued technical integration, evolving pedagogical theories, and an increased focus on preparing learners for global challenges and lifelong learning.

Collisional Shaping of Nuclear Star Cluster Density Profiles

A supermassive black hole surrounded by a dense, nuclear star cluster resides at the center of many galaxies. In this dense environment, high-velocity collisions frequently occur between stars. About 10% of the stars within the Milky Way’s nuclear star cluster collide with other stars before evolving off the main sequence. Collisions preferentially affect tightly bound stars, which orbit most quickly and pass through regions of the highest stellar density. Over time, collisions therefore shape the bulk properties of the nuclear star cluster. We examine the effect of collisions on the cluster’s stellar density profile. We show that collisions produce a turning point in the density profile, which can be determined analytically. Varying the initial density profile and collision model, we characterize the evolution of the stellar density profile over 10 Gyr. We find that old, initially cuspy populations exhibit a break around 0.1 pc in their density profile, while shallow density profiles retain their initial shape outside of 0.01 pc. The initial density profile is always preserved outside of a few tenths of a parsec irrespective of initial conditions. We generalize this model to an arbitrary galactic nucleus and show that the location of the collisional break can be simply estimated from the nuclear properties. Lastly, we comment on the implications of collisions for the luminosity and color of stars in the collisionally shaped inner cluster.

Intermittent Kac's flights and the generalized telegrapher's equation.

A generalized one-dimensional telegrapher equationassociated with an intermittent change of sign in the velocity of a Kac's flight has been proposed. To solve this random differential equation, we used the enlarged master equationapproach to obtain the exact differential equationfor the evolution of a normalized positive distribution. This distribution is associated with a generalized finite-velocity diffusionlike process. We studied the robustness of the ballistic regime, the cutoff of its domain, and the time-dependent Gaussian convergence. The second moment for the evolution of the profile has been studied as a function of non-Poisson statistics (possibly intermittent) for the time intervals Δ_{ij} in the Kac's flight. Numerical results for the evolution of sharp and wide initial profiles have also been presented. In addition, for comparison with a non-Gaussian process at all times, we have revisited the non-Markov Poisson's flight with exponential pulses. A theory for generalized random flights with intermittent stochastic velocity and in the presence of a force is also presented, and the stationary distribution for two classes of potential has been obtained.

Equipping for risk: Lessons learnt from the UK shale-gas experience on assessing environmental risks for the future geoenergy use of the deep subsurface

Summary findings are presented from an investigation to improve understanding of the environmental risks associated with developing an unconventional-hydrocarbons industry in the UK. The EQUIPT4RISK project, funded by UK Research Councils, focused on investigations around Preston New Road (PNR), Fylde, Lancashire, and Kirby Misperton Site A (KMA), North Yorkshire, where operator licences to explore for shale gas by hydraulic fracturing (HF) were issued in 2016, although exploration only took place at PNR. EQUIPT4RISK considered atmospheric (greenhouse gases, air quality), water (groundwater quality) and solid-earth (seismicity) compartments to characterise and model local conditions and environmental responses to HF activities. Risk assessment was based on the source-pathway-receptor approach. Baseline monitoring of air around the two sites characterised the variability with meteorological conditions, and isotopic signatures were able to discriminate biogenic methane (cattle) from thermogenic (natural-gas) sources. Monitoring of a post-HF nitrogen-lift (well-cleaning) operation at PNR detected the release of atmospheric emissions of methane (4.2 ± 1.4 t CH4). Groundwater monitoring around KMA identified high baseline methane concentrations and detected ethane and propane at some locations. Dissolved methane was inferred from stable-isotopic evidence as overwhelmingly of biogenic origin. Groundwater-quality monitoring around PNR found no evidence of HF-induced impacts. Two approaches for modelling induced seismicity and associated seismic risk were developed using observations of seismicity and operational parameters from PNR in 2018 and 2019. Novel methodologies developed for monitoring include use of machine learning to identify fugitive atmospheric methane, Bayesian statistics to assess changes to groundwater quality, a seismicity forecasting model seeded by the HF-fluid injection rate and high-resolution monitoring of soil-gas methane.The project developed a risk-assessment framework, aligned with ISO 31000 risk-management principles, to assess the theoretical combined and cumulative environmental risks from operations over time. This demonstrated the spatial and temporal evolution of risk profiles: seismic and atmospheric impacts from the shale-gas operations are modelled to be localised and short-lived, while risk to groundwater quality is longer-term.

The Thousand-Pulsar-Array programme on MeerKAT – XII. Discovery of long-term pulse profile evolution in seven young pulsars

ABSTRACT A number of pulsars are known to have profile evolution on time-scales of months, often correlated with spin-down rate changes. Here, we present the first result from 3 yr of monitoring observations from MeerKAT as part of the Thousand Pulsar Array programme. This programme obtains high-fidelity pulse profiles for ∼ 500 pulsars, which enabled the detection of subtle changes in seven sources not previously known to exhibit long-term profile evolution. A 2D Gaussian convolution is used to highlight correlated emission variability in both the pulse phase and observing epoch direction. Simulations show that for one additional source the observed profile variability is likely to originate from stochastic single-pulse shape variability (jitter). We find that it is common for long-term profile variability to be associated with changes in polarization fractions, but not with polarization position angle (PA) changes. PA changes are expected if emission height changes or precession is responsible for the profile variability. PSR J1741−3927 is the only pulsar in our sample that shows correlated PA variability, and this is associated with orthogonal polarization mode activity. For the six other pulsars limits on possible emission height changes and impact angle changes are derived. These limits are consistent with the small changes in the total intensity profile shape. None of the sources show detectable spin-down variability correlated with the emission changes, which are thought to be driven by magnetospheric current fluctuations. Therefore, the absence of correlated spin-down rate variability allows upper limits to be placed on changes in the magnetospheric charge density.

Organizational changes and research performance: A multidimensional assessment

Abstract This paper analyzes the research performance evolution of a scientific institute, from its genesis through various stages of development. The main aim is to obtain, and visually represent, bibliometric evidence of the correlation of organizational changes on the development of its scientific performance; particularly, structural and leadership changes. The study involves six bibliometric indicators to multidimensionally assess the evolution of the institution’s performance profile. For a case study, we selected the Renewable Energy Institute at the National Autonomous University of Mexico, created 35 years ago as a small laboratory, then it evolved to a research center and finally to a formal institute, which over the last 8 years changed from the traditional departmental structure to a network-based structure. The evolution of the multidimensional performance profiles is analyzed, and graphically represented, using a novel artificial intelligence-based approach. We analyzed the performance profiles evolution yearly, using Principal Components Analysis, and a self-organizing neural network mapping technique. This approach, combining bibliometric and machine learning techniques, proved to be effective for the assessment of the institution’s evolution process. The results were represented with a series of graphs and maps that clearly reveal the magnitude and nature of the performance profile evolution, as well as its correlation with each of the structural and leadership transitions. These exploratory results have provided us data and insights into the probable effects of these transitions on academic performance, that have been useful to create a dynamical model.

Tethered balloon-borne observations of thermal-infrared irradiance and cooling rate profiles in the Arctic atmospheric boundary layer

Abstract. Clouds play an important role in controlling the radiative energy budget of the Arctic atmospheric boundary layer. To quantify the impact of clouds on the radiative heating or cooling of the lower atmosphere and of the surface, vertical profile observations of thermal-infrared irradiances were collected using a radiation measurement system carried by a tethered balloon. We present 70 profiles of thermal-infrared radiative quantities measured in summer 2020 during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition and in autumn 2021 and spring 2022 in Ny-Ålesund, Svalbard. Measurements are classified into four groups: cloudless, low-level liquid-bearing cloud, elevated liquid-bearing cloud, and elevated ice cloud. Cloudless cases display an average radiative cooling rate of about −2 K d−1 throughout the atmospheric boundary layer. Instead, low-level liquid-bearing clouds are characterized by a radiative cooling up to −80 K d−1 within a shallow layer at cloud top, while no temperature tendencies are identified underneath the cloud layer. Radiative transfer simulations are performed to quantify the sensitivity of radiative cooling rates to cloud microphysical properties. In particular, cloud top cooling is strongly driven by the liquid water path, especially in optically thin clouds, while for optically thick clouds the cloud droplet number concentration has an increased influence. Additional radiative transfer simulations are used to demonstrate the enhanced radiative importance of the liquid relative to ice clouds. To analyze the temporal evolution of thermal-infrared radiation profiles during the transitions from a cloudy to a cloudless atmosphere, a respective case study is investigated.