Complex Configurations Research Articles

Remarkable stability of γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma$$\\end{document}-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document} and its prevalence in the nitrogen phase diagram

Solid nitrogen exhibits a panoply of phenomena ranging from complex molecular crystalline configurations to polymerization and closing band gap at higher densities. Among the elemental molecular solids, nitrogen stands apart for having phases, which can only be stabilized following particular pressure-temperature pathways, indicative of metastability and kinetic barriers. Here, through the combination of Raman spectroscopy and dynamic compression techniques, we find that the appearance of the whole nitrogen phase diagram is determined by the P-T paths taken below 2 GPa. We reveal the existence of the path- and phase-dependent triple point between the β\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\beta$$\\end{document}-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document}, δloc\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\delta _{loc}$$\\end{document}-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document} and γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma$$\\end{document}- or ϵ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\epsilon$$\\end{document}-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document}. We further show that the β\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\beta$$\\end{document}-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document} towards γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma$$\\end{document}-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document} path below the triple point, that evades δ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\delta$$\\end{document}(δloc\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\delta _{loc}$$\\end{document})-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document}, results in the formation of γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma$$\\end{document}-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document}, which in turn becomes a dominant phase. We then demonstrate, that the β\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\beta$$\\end{document}-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document} through δ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\delta$$\\end{document}(δloc\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\delta _{loc}$$\\end{document})-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document} above the triple point path leads to the formation of ϵ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\epsilon$$\\end{document}-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document} and the “well-established” phase diagram. An additional pathway, which by-passes the rotationally inhibited modifications δ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\delta$$\\end{document}(δloc\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\delta _{loc}$$\\end{document})-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document}, via rapid compression is found to produce γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma$$\\end{document}-N2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_2$$\\end{document} at higher temperatures. We argue that the pathway and phase sensitive triple point and the compression rate dependent phase formation challenge our understanding of this archetypal dense molecular solid.

Heat transfer analysis in particulate flow of Williamson fluid with electric double layer effects

This research is conducted to investigate the heat transfer analysis in a two-phase fluid model under the impact of an electric double layer and magnetic field through two types of geometries with porous media. The Darcy model is used to capture the effect of porous medium. The perturbation technique is employed to produce the analytical solution of fluid and particulate velocities, temperature distribution, volumetric flow rate, and stream function. The computational revealed that the two-phase model produces 32 and 36% greater heat transfer as compared to the single-phase model by considering convergent and divergent channels, respectively. It is observed that the divergent channel provides 4% more heat transfer as compared to the convergent channel. The present study will offer valuable insights into the electric double-layer dynamics of two-phase fluid through complex configurations, such as biomedical engineering. The current two-phase model is also very important and applicable in electrofluidic dynamic and biomedical engineering where biomedical electronic devices such as two-phase lab-on-chip may be engineered.

Heteryunine A, an amidated tryptophan-catechin-spiroketal hybrid with antifibrotic activity from Heterosmilax yunnanensis

An unprecedented spiro-C-glycoside adduct, heteryunine A (1), along with two uncommon alkaloids featuring a 2,3-diketopiperazine skeleton, heterpyrazines A (2) and B (3), were discovered in the roots of Heterosmilax yunnanensis. The detailed spectroscopic analysis helped to clarify the planar structures of these compounds. Compound 1, containing 7 chiral centers, features a catechin fused with a spiroketal and connects with a tryptophan derivative by a CC bond. Its complex absolute configuration was elucidated by rotating frame overhauser enhancement spectroscopy (ROESY), specific rotation, and the 13C nuclear magnetic resonance (NMR) and electronic circular dichroism (ECD) calculation. The possible biosynthetic routes for 1 were deduced. Compounds 1 and 2 showed significant antifibrotic effects and further research revealed that they inhibited the activation, migration and proliferation of hepatic stellate cells (HSCs) through suppressing the activity of Ras homolog family member A (RhoA).

Depth accuracy analysis of the ZED 2i Stereo Camera in an indoor Environment

Accurate depth information is crucial for autonomous systems to navigate and interact safely with their surroundings. Passive stereo-vision cameras, such as the ZED 2i, obtain depth information through stereo-image analysis and triangulation. The study measures and assesses the true capabilities of the ZED 2i camera in a real indoor office environment. Furthermore, the study provides a standard test setup to reproduce similar benchmarks with different depth cameras. To achieve the set goals, an experiment was devised and carried out in an office environment to determine the camera depth error and Root Mean Square Error (RMSE) of the depth estimates at different distances using four different image resolutions. The results reveal that the depth error has heavy tails, implying that outliers substantially impact accuracy. Hence, depth errors should not be modeled as normally distributed errors. Moreover, only two out of four resolutions provided the capability of acquiring depth data up to 18 m. These insights provide guidelines for understanding the ZED 2i camera's true capabilities, determining its suitability for different applications and environments, and giving baselines for future tests of other competing sensor units. Furthermore, the study offers a simple, inexpensive, and laboratory space-free, yet effective setup that does not need extensive equipment or complex configurations to facilitate the benchmarking of depth cameras in different working environments.

“TIPS” and Technical Nuances for Digital Illustration in Neurointerventional Surgery

Medical illustrations represent a precious resource for learning surgical anatomy and surgical techniques, allowing preoperative and postoperative reviews. As traditional hand-drawn illustrations are difficult to use and expressing the area of neurointerventional surgery is time-consuming, we proposed methods for neurointerventional surgeons to create digital illustrations (DIs) for neurointerventional surgery using the iPad-exclusive Procreate application (Savage Interactive, Hobart, Australia). Dedicated "digital pens" were created and used for each endovascular device, creating straightforward representations of neurointerventional procedures and changes over time. DIs in neurointervention easily depict changes to highlighted surgical scenes for various devices with complex configurations and structures. DIs are also versatile, allowing easy intrainstitutional and interinstitutional sharing and discussion of technical tips on the manipulation of medical devices (coils, catheters, stents, etc.) among neurointerventional surgeons worldwide. DIs can be applied as educational tools not only in neurointerventional surgery, but also in craniotomy surgery and for surgical records from other specialties.

Simulated TEM imaging of a heavily irradiated metal

We recast the Howie–Whelan equations for generating simulated transmission electron microscope (TEM) images, replacing the dependence on local atomic displacements with atomic positions only. This allows rapid computation of simulated TEM images for arbitrarily complex atomistic configurations of lattice defects and dislocations in the dynamical two beam approximation directly from standard atomistic simulation output files. Large-scale massively-overlapping cascade simulations, performed with molecular dynamics, are used to generate representative high-dose nanoscale defect and dislocation microstructures in tungsten at room temperature. We then compare the simulated TEM images to experimental TEM images with similar irradiation and imaging conditions. The simulated TEM shows ‘white-dot’ damage in weak-beam dark-field imaging conditions, in agreement with our experimental observations and as expected from previous studies, and in bright-field conditions a dislocation network is observed. In this work we also compare the simulated images to the nanoscale lattice defects in the original atomic structures, and find that at high dose the white spots are not only created by small dislocation loops, but rather arise from nanoscale fluctuations in strains around curved sections of dislocation lines.

Digital light processing of high-purity SiC ceramic membrane support modified by SiC whisker

High-purity SiC ceramic membrane has gained tremendous attention in the treatment of various corrosive wastewaters. Additive manufacturing technique makes it possible to fabricate high-purity SiC ceramic membrane with complex configurations. Here, we proposed a route for the preparation of high-purity SiC ceramic membrane support using digital light processing and SiC whisker reinforcement. With the increase of whisker content, the viscosity of SiCw/SiC photosensitive slurry increased due to the formation of whiskers agglomerations; the average pore size shifted from 3.15 μm to 1.35 μm with the occupation of large pores by SiC whiskers. In addition, the compressive strength of the ceramic support increased from 10.7 MPa to 16.7 MPa because of the decline in pore size and the toughening effects by SiC whiskers. So, the introduced SiC whiskers enhanced the pore connectivity and mechanical strength of the porous ceramics. This work provides a feasible path to manufacture high-purity SiC ceramic membrane support with complex configuration, high pore-connectivity and excellent mechanical properties.

Silicon carbide ceramics manufactured by digital light processing and low temperature sintering

The rapid development of additive manufacturing techniques enables the preparation of SiC ceramics with complex configurations; however, the high sintering temperature and defects-control are still great challenges during processing. Thus, SiC ceramics were prepared by digital light processing followed by liquid phase sintering using Al2O3–Y2O3 additives in this study. The photopolymerization of the SiC slurry, microstructures and mechanical properties of the sintered ceramics were investigated. The Al2O3–Y2O3 additives enhanced the curing ability of the photosensitive SiC slurries by reducing the absorbance and scattering of UV light. The liquid phase accelerated the densification of the ceramics by particles rearrangement and interfacial bonding. Thus, the flexural strength of the ceramics increased from 41.0 MPa to 62.8 MPa with sintering temperature increasing.

Towards Wall-Resolved Large-Eddy Simulation of the High-Lift Common Research Model

In the present study, we performed a sixth-order wall-resolved large-eddy simulation (WRLES) of the high-lift Common Research Model (CRM-HL) on the Leadership Class Computing Cluster Summit. During the 4th High-Lift Prediction Workshop (HLPW-4), wall-modeled LES (WMLES) and hybrid Reynolds-averaged Navier–Stokes (RANS)/LES approaches showed promise in predicting the maximum lift and large flow separations near stall. In those simulations, however, laminar and transition regions were not resolved since the flow was assumed to be fully turbulent. If one wants to resolve these regions, the only viable approach is WRLES. The main purpose of the present study is to demonstrate the feasibility of WRLES for a complex real-world configuration at the wind tunnel Reynolds number. A high-order unstructured mesh LES solver called hpMusic was employed in the study. The simulation at solution polynomial order P=5 has more than 14 billion degrees of freedom per equation. Computational results are compared to experimental data in the form of surface oil flows and pressure coefficient profiles. We highlight lessons learned from attempting a grand-challenge type large-scale simulation: 1) such a simulation is feasible but very expensive, estimated to be at least three orders more expensive than WMLES, 2) oil flows produced with WRLES agree very well with experimental oil flows in fine detail, not observed in those produced with WMLES, and 3) flow visualization is a severe bottleneck, and parallel postprocessing capability is needed.

Formation and resolution of meiotic chromosome entanglements and interlocks.

Interactions between parental chromosomes during the formation of gametes can lead to entanglements, entrapments and interlocks between unrelated chromosomes. If unresolved, these topological constraints can lead to misregulation of exchanges between chromosomes and to chromosome mis-segregation. Interestingly, these configurations are largely resolved by the time parental chromosomes are aligned during pachytene. In this Review, we highlight the inevitability of topologically complex configurations and discuss possible mechanisms to resolve them. We focus on the dynamic nature of a conserved chromosomal interface - the synaptonemal complex - and the chromosome movements that accompany meiosis as potential mechanisms to resolve topological constraints. We highlight the advantages of the nematode Caenorhabditis elegans for understanding biophysical features of the chromosome axis and synaptonemal complex that could contribute to mechanisms underlying interlock resolution. In addition, we highlight advantages of using the zebrafish, Danio rerio, as a model to understand how entanglements and interlocks are avoided and resolved.

The history of the development of 3D printing technologies and their use in world artistic ceramics

The article is devoted to the study of the history of the emergence and development of additive technologies in world artistic ceramics. The article analyzes information on the history of the emergence of additive technologies. The principle of operation of 3D printing equipment, features of its use, the most common areas of use and materials used in 3D printing have been considered. An analysis of the specifics of the technical characteristics of 3D printers and technologies for 3D printing with ceramic masses has been shown that the use of ceramic materials as raw materials for 3D printing is a progressive trend due to the emergence of the possibility of forming ceramic objects and products that are practically indestructible reproduction and replication using traditional methods. In this article, the authors have been analyzed the advantages and disadvantages of manufacturing ceramic products by 3D printing. It has been established that the main difference between the production of three-dimensional plastic or metal elements and ceramic elements is the main feature of the ceramic manufacturing technology, namely that the printout is not a ceramic product before firing in the oven, that is, without firing, it is simply an element printed from clay materials (that is, such a printout before firing is called the "green part" – an unprocessed element). Currently, there are no 3D printers that can immediately produce ready-made ceramic products, all elements printed from ceramic materials require drying and firing. But, despite this nuance, printers that print with clay materials are called ceramic 3D printers. As 3D printing can accurately realize the creative thinking of artists and designers, 3D printing technology is increasingly used in the creation of ceramic products and contemporary ceramic works. The authors of the article emphasize that three-dimensional printing with clay provides ceramists with completely new opportunities for creating ceramic products with a complex configuration, texture, etc. Ceramic artists from all over the world are already actively using this technology in their work. Therefore, part of the study is devoted to examples of the use of 3D printing technology in world artistic ceramics, as well as to the description and analysis of the most interesting achievements in this direction of creativity, according to the authors.

The history of the development of 3D printing technologies and their use in world artistic ceramics

The article is devoted to the study of the history of the emergence and development of additive technologies in world artistic ceramics. The article analyzes information on the history of the emergence of additive technologies. The principle of operation of 3D printing equipment, features of its use, the most common areas of use and materials used in 3D printing have been considered. An analysis of the specifics of the technical characteristics of 3D printers and technologies for 3D printing with ceramic masses has been shown that the use of ceramic materials as raw materials for 3D printing is a progressive trend due to the emergence of the possibility of forming ceramic objects and products that are practically indestructible reproduction and replication using traditional methods. In this article, the authors have been analyzed the advantages and disadvantages of manufacturing ceramic products by 3D printing. It has been established that the main difference between the production of three-dimensional plastic or metal elements and ceramic elements is the main feature of the ceramic manufacturing technology, namely that the printout is not a ceramic product before firing in the oven, that is, without firing, it is simply an element printed from clay materials (that is, such a printout before firing is called the "green part" – an unprocessed element). Currently, there are no 3D printers that can immediately produce ready-made ceramic products, all elements printed from ceramic materials require drying and firing. But, despite this nuance, printers that print with clay materials are called ceramic 3D printers. As 3D printing can accurately realize the creative thinking of artists and designers, 3D printing technology is increasingly used in the creation of ceramic products and contemporary ceramic works. The authors of the article emphasize that three-dimensional printing with clay provides ceramists with completely new opportunities for creating ceramic products with a complex configuration, texture, etc. Ceramic artists from all over the world are already actively using this technology in their work. Therefore, part of the study is devoted to examples of the use of 3D printing technology in world artistic ceramics, as well as to the description and analysis of the most interesting achievements in this direction of creativity, according to the authors.

Comparative study of kilonova opacities for three elements of the sixth period (hafnium, osmium, and gold) from new atomic structure calculations in Hf I–IV, Os I–IV, and Au I–IV

Aims. It is now well established that a large amount of heavy (trans-iron) elements are produced during neutron star (NS) mergers. These elements can be detected in the spectra of the kilonova emitted from the post-merger ejected materials. Due to the high level densities that characterize the complex configurations belonging to heavy elements, thus giving rise to millions of absorption lines, the kilonova ejecta opacity is of significant importance. The elements that contribute the most to the latter are those with an unfilled nd subshell belonging to the fifth and the sixth rows of the periodic table, and those with an unfilled nf subshell belonging to the lanthanide and actinide groups. The aim of the present work is to make a new contribution to this field by performing large-scale atomic structure calculations in three specific sixth-row 5d elements, namely hafnium, osmium, and gold, in the first four charge stages (I–IV), and by computing the corresponding opacities, while focusing on the importance of the atomic models used. Methods. The pseudo-relativistic Hartree–Fock (HFR) method, including extended sets of interacting configurations, was used for the atomic structure and radiative parameter calculations, while the expansion formalism was used to estimate the opacities. Results. Theoretical energy levels, wavelengths, and oscillator strengths were computed for millions of spectral lines in Hf I–IV, Os I–IV, and Au I–IV ions, the reliability of these parameters being assessed through detailed comparisons with previously published experimental and theoretical results. The newly obtained atomic data were then used to calculate expansion opacities for typical kilonova conditions expected one day after the NS merger; these are a density of ρ = 10−13 g cm−3 and temperatures ranging from T = 5000 K to T = 15 000 K. Some agreements and differences were found when comparing our results with available data, highlighting the importance of using sufficiently complete atomic models for the determination of opacities.

PSF and MTF from a bar pattern in digital mammography

Background. The MTF has difficulties being determined (according to the provisions of the IEC standards) in the hospital setting due to the lack of resources. Purpose. The objective of this work is to propose a quantitative method for obtaining the point spread function (PSF) and the modulation transfer function (MTF) of a digital mammography system from an image of a bar pattern. Methods. The method is based on the measurement of the contrast transfer function (CTF) of the system over the image of the bar pattern. In addition, a theoretical model for the PSF is proposed, from which the theoretical CTF of the system is obtained by means of convolution with a square wave (mathematical simulation of the bar pattern). Through an iterative process, the free parameters of the PSF model are varied until the experimental CTF coincides with the one calculated by convolution. Once the PSF of the system is obtained, we calculate the MTF by means of its Fourier transform. The MTF calculated from the model PSF have been compared with those calculated from an image of a 65 μm diameter gold wire using an oversampling process. Results. The CTF has been calculated for three digital mammographic systems (DMS 1, DMS 2 and DMS 3), no differences of more than 5 % were found with the CTF obtained with the PSF model. The comparison of the MTF shows us the goodness of the PSF model. Conclusions. The proposed method for obtaining PSF and MTF is a simple and accessible method, which does not require a complex configuration or the use of phantoms that are difficult to access in the hospital world. In addition, it can be used to calculate other magnitudes of interest such as the normalized noise power spectrum (NNPS) and the detection quantum efficiency (DQE).

A Spatiotemporal Model as an Approach for Parameterizing the Inherited Cosmopolitan Urban Areas: Eastern Harbor, Alexandria-Egypt

Eastern Harbor urban areas, Alexandria-Egypt, are inherited cosmopolitan spatial systems formed across eras. Parameterizing their inheritances is a scientific challenge according to their complex configuration and nonmetric meaning and value data. This study developed an approach for calibrating their urban parameter sets as vocabularies and governing grammars based on the space entity. Historical inductive method supports generating a valid spatiotemporal model, facilitating reliable deductive methods for investigating their deep-rooted urban anatomy based on anthropological temporal frames, followed by defining the inherited space-syntax via the resulting ontology-based model. The proposed systematic conceptual approach’s findings would serve informatic-based actions in continuous obsolescence.

Structural analysis of the dynamic ribosome-translocon complex

The protein translocon at the endoplasmic reticulum comprises the Sec61 translocation channel and numerous accessory factors that collectively facilitate the biogenesis of secretory and membrane proteins. Here, we leveraged recent advances in cryo-electron microscopy (cryo-EM) and structure prediction to derive insights into several novel configurations of the ribosome-translocon complex. We show how a transmembrane domain (TMD) in a looped configuration passes through the Sec61 lateral gate during membrane insertion; how a nascent chain can bind and constrain the conformation of ribosomal protein uL22; and how the translocon-associated protein (TRAP) complex can adjust its position during different stages of protein biogenesis. Most unexpectedly, we find that a large proportion of translocon complexes contains RAMP4 intercalated into Sec61’s lateral gate, widening Sec61’s central pore and contributing to its hydrophilic interior. These structures lead to mechanistic hypotheses for translocon function and highlight a remarkably plastic machinery whose conformations and composition adjust dynamically to its diverse range of substrates.

Structural analysis of the dynamic ribosome-translocon complex.

The protein translocon at the endoplasmic reticulum comprises the Sec61 translocation channel and numerous accessory factors that collectively facilitate the biogenesis of secretory and membrane proteins. Here, we leveraged recent advances in cryo-electron microscopy (cryo-EM) and structure prediction to derive insights into several novel configurations of the ribosome-translocon complex. We show how a transmembrane domain (TMD) in a looped configuration passes through the Sec61 lateral gate during membrane insertion; how a nascent chain can bind and constrain the conformation of ribosomal protein uL22; and how the translocon-associated protein (TRAP) complex can adjust its position during different stages of protein biogenesis. Most unexpectedly, we find that a large proportion of translocon complexes contains RAMP4 intercalated into Sec61's lateral gate, widening Sec61's central pore and contributing to its hydrophilic interior. These structures lead to mechanistic hypotheses for translocon function and highlight a remarkably plastic machinery whose conformations and composition adjust dynamically to its diverse range of substrates.

High-precision, programmable soft wireless robotics for cooling tower cleaning based on Internet of Things technology

Soft robotics with high flexibility & adaptability gain attention for precision tasks in unstructured environments. However, non-contact robotics’ reliance on thermal/optical fields limits stability & stimulus uniformity, resulting in low accuracy, poor scalability, & limited adaptability. This paper introduces a new soft robotic system (PM10B2C robotic) incorporated Internet of Things (IoT) technology and leveraged the Joule thermal effect. The robotic platform is constructed by self-prepared boron nitride nanosheets (BNNS) that exhibit a higher planar area-to-thickness ratio. When the actuation voltage is 8 V, the soft wireless robotic can complete κ = 1.19 cm−1 deformation with deformation efficiency and recovery efficiency of 0.11 cm−1·s−1 and 0.17 cm−1·s−1, and exhibits excellent actuation stability under 500 cycles of testing. Based on the Timoshenko bimetallic constant temperature device model and heat conduction theory, a κmax-U analytical model is constructed to achieve effective prediction of the optimal curvature-low voltage D.C. relationship of PM10B2C robotics. The smart-controlled soft robotic operates continuously and stably within the harsh internal environments and complex spatial configurations of thermal power plant in cooling towers. This design offers novel prospects for developing cleaning robotics tailored for extreme environments and complex spaces in such facilities.

Exploring Perception of Warning Labels: Insights from Color, Signal Words, and Symbol Evaluation

Protecting people from the risks associated with products is a critical concern in today’s economy. Pakistan, being the world’s fifth most populous country, lacks the framework of warning labels and therefore faces a significant gap in product warning labels. Pakistan is a representative of a number of countries that export a variety of products to Pakistan; however, warning labels on these goods are typically in English, which might mislead people of Pakistan in perceiving the hazard level. It is therefore imperative to conduct research into the non-textual and cross-cultural understanding of labels from the perspective of Pakistan. This study examined the applicability of ANSI Z535.4 in the context of Pakistan. A total of 66 (34 male and 32 female) undergraduate students with a mean age of 20.5 participated in this study. A meticulous experiment was designed using a nine-point rating scale with anchors on both sides, where one represented ‘not at all hazardous’ and nine represented ‘extremely hazardous’. Participants rated each component of warning labels, i.e., color, symbol, signal words, and their complex configurations. The results showed alignment with the ANSI Z535.4 standards for some components (i.e., colors, symbols, and signal words) and complex configurations, whereas no significant difference was found in perceived hazard levels between green (M = 3.167), blue (M = 3.591, and yellow (M = 3.652) colors, with a p-value greater than 0.05. Participants did not differentiate significantly between signal words, i.e., caution (M = 5.182) and warning (M = 5.879). Participants also did not differentiate significantly between complex configurations, i.e., safety alert–caution–yellow (M = 5.076) and safety alert–warning–orange (M = 5.197), with p-values greater than 0.05. These results state that discrepancies in the perception of warning labels exist. This study is the first of its kind conducted in the context of Pakistan, which will help policy makers to consider the findings before implementing a policy. In fact, differences in perception could result in failure to take appropriate precautions. Nonetheless, these nuances can be overcome with proper awareness through training for the people.

ТЕХНОЛОГИЧЕСКИЕ ПОДХОДЫ ПОВЫШЕНИЯ КАЧЕСТВА МЕЛКОЗЕРНИСТОГО БЕТОНА

The production of high quality and reliable fine-grained concrete using resource-saving technologies is a current and important task. The popularity of fine-grained concrete is determined by the possibility of eliminating coarse aggregate. It is expensive and in short supply in many regions of the country, and the ability to regulate within a wide range the structure and technical properties of the concrete mixture and concrete, by the quality of concreting of densely reinforced structures of complex configuration, increasing the impact strength of reinforced concrete elements. In this regard, to increase the demand for this product, research is carried out on the production of fine-grained concrete using locally available technogenic materials and technical methods based on established patterns of influence of recipe and technological parameters on physical, mechanical and operational characteristics. The lack of high-quality coarse sands in the region was a prerequisite for the search for new solutions to control the processes of contact formation between cement particles and fine aggregate. The recipe-technological method proposed in the work, which consists in the complex use of fractionated filler surface activated by the cationic additive of alkyldimethylbenzylammonium chloride, modified with microsilica binder, contributed to the enhancement of adhesive strength in the contact zone “cement stone-aggregate” and the formation of a dense structure composed of high-strength and poorly soluble formations. The proposed technology for producing fine-grained concrete will make it possible to create high-quality composites using technogenic raw materials, thereby solving the problem of the shortage of coarse natural sands suitable for construction.