bluuebunny/crossref_metadata_2025_split huggingface dataset:
Robust and Stable Atomically Precise Metal Nanoclusters Mediated Solar Water Splitting
Authors: Mo Qiao‐Ling , Dai Xiao‐Cheng , Xiao Fang‐Xing 
Published: April 2023

AbstractAtomically precise metal nanoclusters (NCs) represent an emerging sector of light‐harvesting antennas by virtue of peculiar atomic stacking fashion, quantum confinement effect, and molecular‐like discrete energy band structure. Nevertheless, precise control of charge carriers over metal NCs has yet to be achieved by the short carrier lifetime and intrinsic instability of metal NCs, which renders the complexity of metal NCs‐based photosystems with photoredox mechanisms remaining elusive. Herein, fine tuning of charge migration over metal NCs is demonstrated by constructing directional charge transfer channels in multilayered heterostructure enabled by a facile layer‐by‐layer (LbL) assembly approach, wherein oppositely charged branched poly‐ethylenimine (BPEI) and glutathione (GSH)‐capped gold NCs [Aux NCs, Au25(GSH)18 NCs] are alternately deposited on the metal oxide (MOs: TiO2, WO3, Fe2O3) substrates. TheAux (Au25) NCs layer serves as light‐harvesting antennas for engendering charge carriers, andBPEI interim layer uniformly intercalated at the interface of Aux NCs layer constitutes the tandem hole transport channel for motivating the charge transfer cascade, resulting in the considerably enhanced photoelectrochemical water oxidation performances. Besides, poor photo‐stability of Aux NCs is surmounted by stimulating the hole transfer kinetics process.
Manipulating Molecular Structure to Trigger Ultrafast and Long‐Life Potassium Storage of Fe0.4Ni0.6S Solid Solution
Authors: Cao Liang , Len Zichen , Xu Xin , Chen Zongquan , Zhou Lijun , Geng Hongbo , Lu Xihong 
Published: April 2023

AbstractCurrently, the main obstacle to the widespread utilization of metal chalcogenides (MSx) as anode for potassium‐ion batteries (PIBs) is their poor rate capability and inferior cycling stability as a result of the undesirable electrical conductivity and severe pulverization of the nanostructure during large K‐ions intercalation‐extraction processes. Herein, an ultrafast and long‐life potassium storage of metal chalcogenide is rationally demonstrated by employing Fe0.4Ni0.6S solid‐solution (FNS/C) through molecular structure engineering. Benefiting from improved electroactivity and intense interactions within the unique solid solution phase, the electrical conductivity and structure durability of Fe0.4Ni0.6S are vastly improved. As anticipated, the FNS/C electrode delivers superior rate properties (538.7 and 210.5 mAh g−1 at 0.1 and 10 A g−1, respectively) and long‐term cycle stability (180.8 mAh g−1 at 5 A g−1 after 2000 cycles with a capacity decay of 0.011% per cycle). Moreover, the potassium storage mechanisms of Fe0.4Ni0.6S solid solution are comprehensively revealed by several in situ characterizations and theoretical calculations. This innovative molecular structure engineering strategy opens avenues to achieve high‐quality metal chalcogenides for future advanced PIBs.
Physical Heights of Inland Lakes
Authors: Sneeuw Nico , Bergé-Nguyen Muriel , Crétaux Jean-François 
Published: April 2023

AbstractInland satellite altimetry has gained traction over the past decade and is now routinely used to monitor the water levels of rivers, lakes and reservoirs. The accuracy of such inland water height measurements, at least from radar altimetry is still relatively poor from a geodetic viewpoint, namely in the range of several decimeter. Accuracies from spaceborne laser altimetry, in particular from the ICESat-2 mission, are at cm-level, however, and further progress in the radar altimetry domain is expected from swath-based altimetry by the SWOT mission, (to be) launched December 2022. With accuracies down to cm-level one needs to reconsider the height system definition of inland lake surfaces as obtained from satellite altimetry. Conventionally one subtracts a global geoid model from the altimetry-derived ellipsoidal height to obtain an orthometric height. Without wind stress, seiches and other time-variable height disturbances the lake water surfaces will conform to equipotential surfaces in the Earth’s gravity field. Thus lake surfaces are surfaces of constant dynamic height, from which follows that a lake surface cannot be a surface of constant orthometric or normal height. Because equipotential surfaces are inherently non-parallel, two points at a lake surface can and will have different orthometric height. Although being well-understood in physical geodesy, we will here model this effect and quantify it for various case studies. We demonstrate that the effects can be as large as a few dm for large lakes at high altitudes, which is an order of magnitude that is relevant in terms of satellite altimetry error levels.
Why a Height Theory Must Be Rigorous and Physically Correct
Authors: Vaníček Petr , Santos Marcelo , Kingdon Robert , Foroughi Ismael , Sheng Michael B. 
Published: April 2023

AbstractLet us start with defining what we understand by a height system. A height system is a conglomerate of reference surface upon which height H = 0, and a recipe for how heights above that surface are obtained from observations. Two such systems, which we call the classical or Gauss-Stokes’s system and the Molodensky system, are used in practical height measurement.The reference surface used by the classical system is the Geoid and its usage is based on valid physical arguments. Determination of the height above the geoid requires data at the surface of the Earth obtained by levelling, gravimetry, sea level measurements, and topographical density from geological measurements. This system served us well when decimetre height accuracy was required and will continue doing so even now when one or even two orders of magnitude better accuracy is needed. On the other hand, Molodensky’s system uses the quasigeoid as a reference surface; this surface is ill suited for a global height system. This paper argues the case that the standard classical reference surface, the geoid, should be used in practice everywhere.
An Introduction to Sparse Matrices
Authors: Scott Jennifer , Tůma Miroslav 
Published: April 2023

AbstractConsider the simple matrix A on the left in Figure 1.1. Many of its entries are zero (and so are omitted). This is an example of a sparse matrix. The problem we are interested in is that of solving linear systems of equations Ax = b, where the square sparse matrix A and the vector b are given and the solution vector x is required. Such systems arise in a huge range of practical applications, including in areas as diverse as quantum chemistry, computer graphics, computational fluid dynamics, power networks, machine learning, and optimization. The list is endless and constantly growing, together with the sizes of the systems. For efficiency and to enable large systems to be solved, the sparsity of A must be exploited and operations with the zero entries avoided. To achieve this, sophisticated algorithms are required.
Sparse Approximate Inverse Preconditioners
Authors: Scott Jennifer , Tůma Miroslav 
Published: April 2023

AbstractConsider a preconditioner M based on an incomplete LU (or Cholesky) factorization of a matrix A. M−1, which represents an approximation of A−1, is applied by performing forward and back substitution steps; this can present a computational bottleneck. An alternative strategy is to directly approximate A−1 by explicitly computing M−1. Preconditioners of this kind are called sparse approximate inverse preconditioners. They constitute an important class of algebraic preconditioners that are complementary to the approaches discussed in the previous chapter. They can be attractive because when used with an iterative solver, they can require fewer iterations than standard incomplete factorization preconditioners that contain a similar number of entries while offering significantly greater potential for parallel computations.
Sparse Cholesky Solver: The Symbolic Phase
Authors: Scott Jennifer , Tůma Miroslav 
Published: April 2023

AbstractThis chapter focuses on the symbolic phase of a sparse Cholesky solver. The sparsity pattern $$\mathcal {S}\{A\}$$
S
{
A
}
of the symmetric positive definite (SPD) matrix A is used to determine the nonzero structure of the Cholesky factor L without computing the numerical values of the nonzeros.
Sparse Cholesky Solver: The Factorization Phase
Authors: Scott Jennifer , Tůma Miroslav 
Published: April 2023

AbstractHaving considered the symbolic phase of a sparse Cholesky solver in the previous chapter, the focus of this chapter is the subsequent numerical factorization phase. If A is a symmetric positive definite (SPD) matrix, then it is factorizable (strongly regular) and (in exact arithmetic) its Cholesky factorization A = LLT exists. LDLT factorizations of general symmetric indefinite matrices are considered in Chapter 7.
Sparse LU Factorizations
Authors: Scott Jennifer , Tůma Miroslav 
Published: April 2023

AbstractThis chapter considers the LU factorization of a general nonsymmetric nonsingular sparse matrix A. In practice, numerical pivoting for stability and/or ordering of A to limit fill-in in the factors is often needed and the computed factorization is then of a permuted matrix PAQ. Pivoting is discussed in Chapter 7 and ordering algorithms in Chapter 8.
Wohnungsnot
Authors: Finzi Jan A. 
Published: April 2023

ZusammenfassungDer zentrale Untersuchungsgegenstand der vorliegenden Arbeit ist das Phänomen der Wohnungsnot. Im öffentlichen Raum begegnet man zwangsläufig Menschen, die sichtbar in Wohnungsnot leben, aber auch Menschen die in Wohnungsnot leben, denen man diese aber nicht ansieht. Diese machen sich unsichtbar, um die Ausgrenzungen und Abwertungen, die mit dem Phänomen seit jeher verbunden sind, auszuweichen (Wolf, 2016, S. 9–10).
Methodische Schlussfolgerungen aus der Theorie
Authors: Finzi Jan A. 
Published: April 2023

ZusammenfassungDie Implikationen aus den vorhergehenden Theoriekapiteln für den sich daraus ergebenden Aufbau und das sich daraus ergebende Vorgehen der vorliegenden Arbeit werden im Folgenden dargestellt. Aufbau und Vorgehen werden detailliert beschrieben und mittels einer graphischen Darstellung unterstützt.
Zugang 2: Strukturelle Stigmatisierung
Authors: Finzi Jan A. 
Published: April 2023

ZusammenfassungDie vorliegende Arbeit und deren vier einzelne Untersuchungen sind insgesamt auf der Strukturebene zu verorten (siehe Kapitel 6 Methodische Schlussfolgerungen aus der Theorie). Nach der Untersuchung der Öffentlichen Stigmatisierung (siehe Kapitel 7 Zugang 1: Öffentliche Stigmatisierung) wird im zweiten Zugang die Strukturelle Stigmatisierung untersucht. Im Fokus des zweiten Zugangs steht das qualifizierte Hilfesystem für Menschen in Wohnungsnot.
Diskussion
Authors: Finzi Jan A. 
Published: April 2023

ZusammenfassungDie vorgestellte Untersuchung ist in ihrer Art und ihrem Umfang bisher einmalig (siehe Abschnitt 3.2 Forschungsstand und Forschungsbedarf) und hat das übergeordnete Ziel, die Teilhabe und Stigmatisierung – als Barriere der Teilhabe – von Menschen in Wohnungsnot zu eruieren. Zugleich wird ein neuer theoretischer Bezugsrahmen zur umfassenden Betrachtung von Wohnungsnot und den damit einhergehenden Lebenslagen vorgestellt. Ausgehend von dieser intersektionalen Perspektive und dem theoretischen Vorwissen werden die beiden Kategorien Geschlecht und Gesundheit als bedeutende Ungleichheitslagen im Kontext von Wohnungsnot identifiziert und analysiert.
Leading all-loop quantum contribution to the effective potential in general scalar field theory
Authors: Kazakov D. I. , Iakhibbaev R. M. , Tolkachev D. M. 
Published: April 2023

Abstract
The RG equation for the effective potential in the leading log (LL) approximation is constructed which is valid for an arbitrary scalar field theory in 4 dimensions. The solution to this equation sums up the leading log ϕ contributions to all orders of perturbation theory. In general, this is the second order nonlinear partial differential equation, but in some cases it can be reduced to the ordinary one. For particular examples, this equation is solved numerically and the LL effective potential is constructed. The solution has a characteristic discontinuity replacing the Landau pole typical for the ϕ4 theory. For a power-like potential no new minima appear due to the Coleman-Weinberg mechanism.
AdS Witten diagrams to Carrollian correlators
Authors: Bagchi Arjun , Dhivakar Prateksh , Dutta Sudipta 
Published: April 2023

Abstract
Carrollian Conformal Field Theories (CFTs) have been proposed as co-dimension one holographic duals to asymptotically flat spacetimes as opposed to Celestial CFTs which are co-dimension two. In this paper, drawing inspiration from Celestial holography, we show by a suitable generalisation of the flat space limit of AdS that keeps track of the previously disregarded null direction, one can reproduce Carrollian CFT correlation functions from AdS Witten diagrams. In particular, considering Witten diagrams in AdS4, we reproduce two and three-point correlation functions for three dimensional Carrollian CFTs in the so-called delta-function branch. Along the way, we construct non-trivial Carrollian three-point functions in the delta-branch by considering a collinear limit. We also obtain a generalised anti-podal matching condition that now depends on the retarded time direction.
A structural model of the iRhom–ADAM17 sheddase complex reveals functional insights into its trafficking and activity
Authors: Kahveci-Türköz Selcan , Bläsius Katharina , Wozniak Justyna , Rinkens Cindy , Seifert Anke , Kasparek Petr , Ohm Henrike , Oltzen Shixin , Nieszporek Martin , Schwarz Nicole , Babendreyer Aaron , Preisinger Christian , Sedlacek Radislav , Ludwig Andreas , Düsterhöft Stefan 
Published: April 2023

AbstractSeveral membrane-anchored signal mediators such as cytokines (e.g. TNFα) and growth factors are proteolytically shed from the cell surface by the metalloproteinase ADAM17, which, thus, has an essential role in inflammatory and developmental processes. The membrane proteins iRhom1 and iRhom2 are instrumental for the transport of ADAM17 to the cell surface and its regulation. However, the structure–function determinants of the iRhom–ADAM17 complex are poorly understood. We used AI-based modelling to gain insights into the structure–function relationship of this complex. We identified different regions in the iRhom homology domain (IRHD) that are differentially responsible for iRhom functions. We have supported the validity of the predicted structure–function determinants with several in vitro, ex vivo and in vivo approaches and demonstrated the regulatory role of the IRHD for iRhom–ADAM17 complex cohesion and forward trafficking. Overall, we provide mechanistic insights into the iRhom–ADAM17-mediated shedding event, which is at the centre of several important cytokine and growth factor pathways.
Continuous Mean Distance of a Weighted Graph
Authors: Garijo Delia , Márquez Alberto , Silveira Rodrigo I. 
Published: April 2023

AbstractWe study the concept of the continuous mean distance of a weighted graph. For connected unweighted graphs, the mean distance can be defined as the arithmetic mean of the distances between all pairs of vertices. This parameter provides a natural measure of the compactness of the graph, and has been intensively studied, together with several variants, including its version for weighted graphs. The continuous analog of the (discrete) mean distance is the mean of the distances between all pairs of points on the edges of the graph. Despite being a very natural generalization, to the best of our knowledge this concept has been barely studied, since the jump from discrete to continuous implies having to deal with an infinite number of distances, something that increases the difficulty of the parameter. In this paper, we show that the continuous mean distance of a weighted graph can be computed in time roughly quadratic in the number of edges, by two different methods that apply fundamental concepts in discrete algorithms and computational geometry. We also present structural results that allow for a faster computation of this continuous parameter for several classes of weighted graphs. Finally, we study the relation between the (discrete) mean distance and its continuous counterpart, mainly focusing on the relevant question of convergence when iteratively subdividing the edges of the weighted graph.
Projections and Angle Sums of Belt Polytopes and Permutohedra
Authors: Godland Thomas , Kabluchko Zakhar 
Published: April 2023

AbstractLet$$P\subset \mathbb {R}^n$$P⊂Rnbe a belt polytope, that is a polytope whose normal fan coincides with the fan of some hyperplane arrangement$${\mathcal {A}}$$A. Also, let$$G:\mathbb {R}^n\rightarrow \mathbb {R}^d$$G:Rn→Rdbe a linear map of full rank whose kernel is in general position with respect to the faces ofP. We derive a formula for the number ofj-faces of the “projected” polytopeGPin terms of thej-th level characteristic polynomial of$${\mathcal {A}}$$A. In particular, we show that the face numbers ofGPdo not depend on the linear mapGprovided a general position assumption is satisfied. Furthermore, we derive formulas for the sum of the conic intrinsic volumes and Grassmann angles of the tangent cones ofPat all of itsj-faces. We apply these results to permutohedra of typesAandB, which yields closed formulas for the face numbers of projected permutohedra and the generalized angle sums of permutohedra in terms of Stirling numbers of both kinds and theirB-analogues.
Exposure to dietary fatty acids oleic and palmitic acid alters structure and mechanotransduction of intestinal cells in vitro
Authors: Bergen Janice , Karasova Martina , Bileck Andrea , Pignitter Marc , Marko Doris , Gerner Christopher , Del Favero Giorgia 
Published: April 2023

AbstractIntestinal cells are continuously exposed to food constituents while adapting to peristaltic movement and fluid shear stress. Oleic acid (OA) and palmitic acid (PA) are among the most prevalent fatty acids with respect to dietary lipids. Despite the central importance of dietary lipids for a balanced diet, awareness about potential detrimental effects related to excessive consumption is increasing; this includes toxicity, metabolic deregulation, and, particularly for cancer cells, a benefit from the uptake of fatty acids related to promotion of metastasis. Expanding on this, we started elucidating the effects of OA and PA (25–500 µM) on non-transformed human intestinal epithelial cells (HCEC-1CT) in comparison to colon carcinoma cells (HCT116), with regard to the mechanosensory apparatus. Hence, intestinal cells’ motility is on the one side essential to ensure adaption to peristaltic movement and barrier function, but also to enable metastatic progression. Incubation with both OA and PA (≥ 25 µM) significantly decreased membrane fluidity of HCT116 cells, whereas the effect on HCEC-1CT was more limited. Application of rhodamine-labelled PA demonstrated that the fatty acid is incorporated into the plasma membrane of HCT116, which could not be observed in the non-tumorigenic cell line. Down-streaming into the intracellular compartment, a pronounced rearrangement of actin cytoskeleton was evident in both cell lines (OA and PA; 25 and 100 µM). This was accompanied by a variation of translocation efficiency of the mechanosensitive co-transcription factor YAP1, albeit with a stronger effect seen for PA and the cancer cells. Untargeted proteomic analysis confirmed that exposure to OA and PA could alter the response capacity of HCT116 cells to fluid shear stress. Taken together, OA and PA were able to functionally modulate the mechanosensory apparatus of intestinal cells, implying a novel role for dietary fatty acids in the regulation of intestinal pathophysiology.
Atmospheric undular bores
Authors: Constantin A. , Johnson R. S. 
Published: April 2023

AbstractWe show that a recently-derived model for the propagation of nonlinear waves in the atmosphere admits undular bores as travelling-wave solutions. These solutions represent waves consisting of a damped oscillation behind a front that is preceded by a uniform breeze-type flow. The generation of such wave profiles requires a jump in the heat source across the leading front of the wave, a feature that is consistent with observations.
femtoPro: virtual-reality interactive training simulator of an ultrafast laser laboratory
Authors: Brixner Tobias , Mueller Stefan , Müller Andreas , Knote Andreas , Schnepp Wilhelm , Truman Samuel , Vetter Anne , von Mammen Sebastian 
Published: April 2023

AbstractThe huge field of optics and photonics research and development is in constant demand of well-trained experts. However, it is challenging to teach efficiently the setup process of complicated optical experiments due to limited hardware availability and eye-safety concerns, in particular, in the case of femtosecond lasers. We have developed an interactive simulation of an ultrafast laser laboratory (“femtoPro”) for teaching and training, implementing physical models for the calculation and visualization of Gaussian laser beam propagation, ultrashort optical pulses, their modulation by typical optical elements, and linear as well as nonlinear light–matter interaction. This facilitates the setup and simulated measurement procedure, in virtual reality (VR) and at real-time speeds, of various typical optical arrangements and spectroscopy schemes such as telescopes, interferometers, or pulse characterization. femtoPro can be employed to supplement academic teaching in connection with regular courses in optics or spectroscopy, to train future scientists and engineers in the field of (ultrafast) optics in practical skills, to communicate to other researchers how to set up and align a particular experiment, to “test-build” and simulate new designs of optical setups, to simulate ultrafast spectroscopy data, to offer practical exercises to high-school students, and to reach out to the general public.
The spherical ensemble and quasi-Monte-Carlo designs
Authors: Berman Robert J. 
Published: April 2023

AbstractThe spherical ensemble is a well-known ensemble of N repulsive points on the two-dimensional sphere, which can realized in various ways (as a random matrix ensemble, a determinantal point process, a Coulomb gas, a Quantum Hall state...). Here we show that the spherical ensemble enjoys remarkable convergence properties from the point of view of numerical integration. More precisely, it is shown that the numerical integration rule corresponding to N nodes on the two-dimensional sphere sampled in the spherical ensemble is, with overwhelming probability, nearly a quasi-Monte-Carlo design in the sense of Brauchart-Saff-Sloan-Womersley for any smoothness parameter $$s\le 2.$$

s
≤
2
.

The key ingredient is a new explicit sub-Gaussian concentration of measure inequality for the spherical ensemble.