bluuebunny/crossref_metadata_2025_split huggingface dataset:
Doubly warped product manifolds with the structure of hyperbolic Ricci solitons
Authors: Açıkgöz Kaya Dilek 
Published: October 2024

Abstract
In this paper we study hyperbolic Ricci solitons on doubly warped product manifolds. The necessary conditions are obtained for a hyperbolic Ricci soliton with the structure of a doubly warped product to be an Einstein manifold when we consider the potential field as a Killing or a conformal vector field. Also, we examined the behavior of hyperbolic Ricci solitons on doubly warped product space-times.
Tunable and strong circular dichroism metamaterial absorber based on gold-VO2 hybrid structure
Authors: Yi Qianyi , Li Jiaying , Xu Jian , Li Wei , Peng Yuxiang , Liu Yuanyuan , He Mengdong 
Published: October 2024

Abstract
The existing terahertz chiral absorber faces a series of issues, including low efficiency, un-tunable absorption, and complex structure. We present a chiral metamaterial absorber integrated with gold and phase-change material vanadium dioxide (VO2) to address the issues above. Our designed metamaterial absorber’s maximum circular dichroism (CD) value, as an ideal chirality-selective meta-absorber, reaches 0.95 when VO2 behaves as a metallic state. However, when VO2 is in the insulator state, the CD value is merely 0.003. Notably, the intrinsic mechanisms of the CD effect are revealed by analyzing the difference in electromagnetic response under left-handed circularly polarized (LCP) and right-handed circularly polarized (RCP) illumination. The designed chiral metamaterial absorber supports the free switching of the CD signal between ‘on’ and ‘off’ states by continuously adjusting the conductivity of VO2 with a CD value ranging from 0 to 0.95. Moreover, the absorption performance of chiral metamaterials is affected by geometric parameters and the angle of incidence. To evaluate the capability of chiral structure in biosensing, three typical avian influenza viruses are sensed by detecting changes in their resonant frequencies and CD values. Finally, the presented chiral-selective absorber with phase-change materials has an important reference value in the terahertz range for constructing chiral light detectors, chiral thermal switching, biosensors, and tunable chiral photonics.
Enchanting optical, electronic, and mechanical properties of the sodium based Na2MgSiZ6 (Z = I, Br, Cl) halides have been explored through DFT
Authors: Iqbal Javed , Ullah Habib , Archi Marouane , Ullah Naimat , Ullah Saeed , Ullah Riaz , Iqbal Zafar 
Published: October 2024

Abstract

Materials. with perovskite structures have been extensively studied due to their remarkable properties, which are important in various aspects of daily life. In the present approach, Na2MgSiZ6 (Z = I, Br, Cl) halides were extensively studied, and it was realized from the band structure results that all these halides display semiconducting natures with indirect band gaps. The semiconducting natures of Na2MgSiZ6 (Z = I, Br, Cl) halides were further confirmed by their TDOS results. The optimized values of the lattice constants were found to be 11.70 Å, 10.4 Å, and 10.22 Å for Na2MgSiI6, Na2MgSiBr6, and Na2MgSiCl6, respectively. Moreover, the largest volume was observed for the Na2MgSiI6 compound, while the smallest volume was recorded for the Na2MgSiCl6 compound. Na2MgSiCl6 compound exhibited brittle nature, whereas Na2MgSiBr6 and Na2MgSiI6 were found to be ductile. All three materials demonstrated attractive values of optical conductivities, making them befitting candidates for solar cells, LEDs, detectors, and various other optoelectronic devices. From the achieved negative values of formation energy for all the Na2MgSiZ6 (Z = I, Br, Cl) halides, it was comprehended that these compounds could be synthesized practically.
Coscattering in the extended singlet-scalar Higgs portal
Authors: Sáez Bastián Díaz , Lahiri Jayita , Möhling Kilian 
Published: October 2024

AbstractWe study the coscattering mechanism in a simple Higgs portal which add two real singlet scalars to the Standard Model. In this scenario, the lighter scalar is stabilized by a single 𝒵2symmetry and acts as the dark matter relic, whose freeze-out is driven by conversion processes. The heavier scalar becomes an unstable state which participate actively in the coscattering. We find viable parameter regions fulfilling the measured relic abundance, while evading direct detection and big-bang nucleosynthesis bounds. In addition, we discuss collider prospects for the heavier scalar as a long-lived particle at present and future detectors.
Excess cataloged X-ray and radio sources at galaxy-cluster virial shocks
Authors: Ilani Gideon , Hou Kuan-Chou , Keshet Uri 
Published: October 2024

Abstract
We detect a highly significant excess of X-ray (2RXS) and radio (NVSS, GMRT, VLSSr) catalog sources when stacked around MCXC galaxy clusters and groups, narrowly confined within ≲ 100 kpc of the ∼ 2.4 R
500 virial shock radius (inferred from previous continuum stacking), with similar X-ray (∼ 4σ for 443 clusters) and radio (∼ 4σ for 485 clusters) characteristics (> 5σ joint).
The excess sources show 10–100 kpc scales, LX
(0.1 – 2.4 keV)≃ 1042-43 erg s-1 or νLν
(ν = 1.4 GHz) ≃ 1040-41 erg s-1 luminosities, and a preferentially radial radio-polarization.
The narrow localization and properties of the excess identify these sources not as AGN, often invoked speculatively for excess X-ray sources at cluster outskirts, but rather as infalling gaseous clumps interacting with the virial shock, probably galactic halos and possibly outflow remnants.
The local excess of such discrete, radio-to-γ-ray sources around an object can probe its virial shock also at high redshifts and sub-cluster scales.
Sound horizon independent constraints on early dark energy: the role of supernova data
Authors: Kable Joshua A. , Miranda Vivian 
Published: October 2024

Abstract
We assess the consistency of cosmological models that alter the size of the sound horizon at last scattering to resolve the Hubble tension with data from ACT + Planck CMB lensing, Big Bang Nucleosynthesis, and supernova data from Pantheon or Pantheon+. We use early dark energy (EDE) as an example model but conclude that the results could apply to other similar models. We constrain ΛCDM and EDE with these data finding that while they can constrain ΛCDM very tightly, EDE opens up the parameter space significantly and allows H
0 > 72 km s-1Mpc-1. We combine these data with measurements from ACT + Planck TT650TEEE CMB primary anisotropy and galaxy baryon acoustic oscillations, and find that overall, EDE fits these data better than ΛCDM at ≈ 2σ. However, the fit to specifically the sound-horizon-independent measurements is worse for EDE than ΛCDM. We assess this increase in χ
2 coming from the sound-horizon-independent measurements and find that the best-fit model is still consistent with a random statistical fluctuation even with H
0 values around 72 km s-1Mpc-1. Finally, we find that supernova data play an important role in constraining EDE-like models with higher preferred values of Ω
m
, as preferred by Pantheon+, reducing the allowed parameter space for H
0 values greater than 70 km s-1Mpc-1.
Drying trend in land and sea in East Asia during the warm season over the past four decades
Authors: Kim Go-Un , Oh Hyoeun , Jeong Jin-Yong 
Published: October 2024

Abstract
The East Asian region is typically characterized by warm and humid conditions from late spring to summer. However, in recent decades, this region has experienced an increase in severe drying conditions, deviating from historical climatological patterns. This study investigated the precipitation − evaporation (P − E) trends across land and sea regions in East Asia (EA) during the extended summer season (April–September) from 1980 to 2022, and the key physical processes driving these trends through moisture budget decomposition and numerical experiments. The results reveal pronounced drying trends in southeastern China and the Yellow Sea and parts of the Korea Strait and Korean Peninsula over the past 43 years. The underlying physical processes driving these drying conditions differ between land and sea in EA. In southeastern China, the drying is driven by dynamic processes, particularly moisture divergence related to wind changes. This is linked to anomalous strengthening of descending motion due to the Indo-Pacific warm pool warming induced by both anthropogenic global warming and natural Pacific Decadal Oscillation-like sea surface temperature (SST) patterns. Conversely, drying in the Yellow Sea and adjacent areas is influenced by thermodynamic moisture advection. The altered humidity distribution due to global warming-induced SST patterns, which are higher over the Northwest Pacific marginal sea and lower in inland China, drives dry air transport from inland China to the Yellow Sea via background southwesterly wind. These findings enhance our understanding of the drying trend and their distinct processes in EA’s land and sea areas during the extended summer.
HELGA: a global hydro-economic model of groundwater-fed irrigation from a farmer’s perspective
Authors: Melo-León Sioux F , Reinhard Stijn , Bierkens Marc F P , van Beek Rens 
Published: October 2024

Abstract
Overexploitation of groundwater for irrigation can ultimately threaten the viability of agriculture itself, because the falling groundwater levels become too deep to sustain the increasing costs of groundwater extraction, an economic limit is reached. In order to evaluate possible adaptation strategies to avoid or postpone reaching the economic limit, we developed the microeconomic heuristic model HELGA (hydro-economic limits as a global analysis). HELGA considers the interaction of groundwater with irrigation at the farm level with a global scale application in mind. HELGA evaluates the development of the costs and revenue of groundwater-fed irrigated agriculture from the farmer’s perspective. As long as the farm remains economically viable, the farmer can invest to access deeper groundwater, but in the long run the famer may have to adapt to keep farming profitable. We applied HELGA in five locations within the conterminous USA. In most cases, recharge is large enough to save a farmer from reaching the economic limit. Where groundwater is overexploited, the increasing energy cost of groundwater pumping is one of the main drivers limiting groundwater use. Additionally, the increasing costs of the water infrastructure (i.e. deeper wells) is a crucial factor that explains where and when the economic limit is reached. If farmers change crops wisely or fallow part of their land, they are able to access groundwater longer and postpone the moment the economic limit is reached. Using HELGA, we show that proper and timely adaptation measures increases the profitable lifetime of groundwater and helps to conserve this resource for future generations.
Protecting the environment at home or abroad?
Authors: Presberger David , Kolcava Dennis , Bernauer Thomas 
Published: October 2024

Abstract
By importing goods whose production affects the environment abroad, wealthy countries are ‘offshoring’ a large share of their total environmental footprint of consumption to less affluent societies. We argue that current efforts to mitigate this problem, which focus largely on informational policy instruments for global supply chains, could result in unintended side effects. The reason pertains to a potential tradeoff between a home bias in consumption and the geographic allocation of environmental impacts. We develop a theoretical argument on how consumers may respond when they prefer a domestically produced good but are made aware that this results in more environmental damage at home, compared to importing the same product from abroad. Based on choice experiments in Germany, Japan, and the United States, we observe that information provision can reduce consumer demand for environmentally harmful products, but also find some support for environmental NIMBYism when environmental and provenance information are combined. The key implication of this finding is that policymakers should address potentially unintended side-effects of more stringent informational requirements for global supply chains.
Plaquette models, cellular automata, and measurement-induced criticality
Authors: Liu Hanchen , Chen Xiao 
Published: October 2024

Abstract
We present a class of two-dimensional randomized plaquette models, where the multi-spin interaction term, referred to as the plaquette term, is replaced by a single-site spin term with a probability of

1
−
p

. By varying p, we observe a ground state phase transition, or equivalently, a phase transition of the symmetry operator. We find that as we vary p, the symmetry operator changes from being extensive to being localized in space. These models can be equivalently understood as 1+1D randomized cellular automaton dynamics, allowing the 2D transition to be interpreted as a 1+1D dynamical absorbing phase transition. In this paper, our primary focus is on the plaquette term with three or five-body interactions, where we explore the universality classes of the transitions. Specifically, for the model with five-body interaction, we demonstrate that it belongs to the same universality class as the measurement-induced entanglement phase transition observed in 1+1D Clifford dynamics, as well as the boundary entanglement transition of the 2D cluster state induced by random bulk Pauli measurements. This work establishes a connection between transitions in classical spin models, cellular automata, and hybrid random circuits.
Stochastic bra-ket interpretation of quantum mechanics
Authors: Öttinger Hans Christian 
Published: October 2024

Abstract
The stochastic nature of quantum mechanics is more naturally reflected in a bilinear two-process representation of density matrices rather than in squared wave functions. This proposition comes with a remarkable change of the entanglement mechanism: entanglement effects do not originate from superpositions of wave functions, but they result from the bilinear structure of density matrices. Quantum interference appears as a multiplicative phenomenon rather than an additive superposition mechanism. We propose two general requirements such that the bilinear representation of density matrices is given in terms of two uniquely defined, identically distributed, Markovian stochastic jump processes. These general ideas are illustrated for the Einstein-Podolsky-Rosen and double-slit experiments. The expression of the stochastic nature of quantum mechanics in terms of random variables rather than their probability distributions facilitates an ontological viewpoint and leads us to a bra-ket interpretation of quantum mechanics.
Lightweighting cost impacts on market adoption and GHG emissions in U.S. light-duty vehicle fleet
Authors: Yang Fan , Brooker Aaron , Kleinbaum Sarah , Gotthold David 
Published: October 2024

Abstract
Vehicle lightweighting is a promising strategy that can reduce energy consumption and GHG emissions without compromising vehicle’s performance or size. The cost of lightweighting plays a critical role in determining the adoption of lightweighting technologies by consumers and manufacturers among advanced vehicle technologies. This analysis estimates the cost of lightweighting needed to achieve significant light-duty vehicle adoption to provide reductions in use-phase GHG emissions. Three different costs of lightweighting scenarios in the U.S. market including a baseline scenario, advanced technology scenario, and widespread scenario are evaluated employing Automotive Deployment Options Projection Tool (ADOPT) in conjunction with other technology improvement assumptions (e.g., advancements in fuel and battery technologies, and material price reductions) from DOE. ADOPT leverages a database of over 700 existing vehicle models and options, enabling it to provide a high degree of realism and capture the unique characteristics of popular vehicles and the endogenously evolvement of the vehicle options. For baseline scenario, the use-phase GHG emissions are reduced by more than 50% and lightweighting fraction reaches 15% by 2046 compared to 2015 levels. The widespread scenario further reduces the GHG emissions by about 4% from the additional 10% glider mass reduction compared to the baseline scenario. The benefit came largely from lightweighting being implemented in the large market segment of lower-price vehicles, due to the relatively low lightweighting cost ($5/kg).
Optical wavefront shaping in deep tissue using photoacoustic feedback
Authors: Xia Fei , Leite Ivo , Prevedel Robert , Chaigne Thomas 
Published: October 2024

Abstract
Over the past decade, optical wavefront shaping has been developed to focus light through highly opaque scattering layers, opening new possibilities for biomedical applications. To probe light intensity deep inside soft scattering media such as biological tissues, internal guide-stars are required. Here, we give an overview of the main principles and describe in depth the use of a photoacoustic feedback signal for this purpose. We further present first principles calculations and simulations to estimate important experimental parameters, and detailed instructions on designing and conducting these experiments. Finally, we provide guidance towards selecting suitable equipment for building a typical experimental setup, paving the way for further innovative biomedical imaging and therapy applications.
Leveraging wearable sensors and machine learning for posture-based detection of carpal tunnel syndrome
Authors: Gautam Nikita , Gupta Sunil Kumar , Shrivastava Amit 
Published: October 2024

Abstract
Carpal tunnel is associated with long-term use of the wrist and hand for various activities such as typing, welding, or poor working postures. Carpal Tunnel Syndrome (CTS) may cause severe pain and discomfort in the hand and wrist, and in some circumstances, surgery becomes inevitable. The objective of this study is to prevent typing postures, which can be ascertained as predisposing subjects to CTS development. The data used in this study is an array of wrist wearable sensors to capture flexion, extension, and bending of fingers while using a keyboard or mouse. Machine learning is employed on the data in order to identify risk factors indicative of a high probability of CTS. The analyzed models are linear regression, Support Vector Machine, Random Forest, Multilayer Perceptron, Convolution Neural Network, and Long Short Term Memory. The conditions for assessing the performance of the data models include RMS error, coefficients of determination, and mean absolute percentage error. In this research, I conducted an exploratory data analysis (EDA) to gain an initial understanding of the dataset. Following the exploratory phase, I applied feature extraction techniques, specifically Principal Component Analysis (PCA). As put forward for the proposed research, the strategies to prevent risky occupations have broad potential at the present time, especially in the case of CTS when preventing repetitive wrist movements.
Regulating Rivalry
Authors: Beitz Charles R 
Published: October 2024

Abstract
The second lecture begins by drawing lessons about democratic representation from the intimations of failure canvassed in the first lecture. It goes on to sketch a normative conception of democratic representation as a properly regulated competitive system. The basic idea is that competition is a distinctive means of solving problems that depends on its participants conducting themselves as adversaries. We rely on competition to produce social value. The problem is that, if not properly regulated, political competition can run off the rails, defeating its social purposes. A central problem for a theory of democratic representation is to identify the purposes we rely on political competition to produce and the arenas in which competition can produce them. The lecture notes four such purposes: to produce policy responsive to the settled will of the majority; to avoid predictable forms of substantive injustice; to resolve conflict effectively, at least insofar as it pertains to broadly valued public functions; and to maintain deliberative environments in both the institutional and public spheres conducive to epistemically responsible judgment by public officials and citizens. The purposes can be realized in different ways and to different extents in the various competitive arenas that make up the system. To illustrate, we consider three arenas of competition—electoral competition, party competition, and interest competition—and ask what it would mean for competition in these arenas to be fairly regulated. It emerges that well-regulated competition among healthy political parties is a necessary condition of fair and effective representation.
Intimations of Failure
Authors: Beitz Charles R 
Published: October 2024

Abstract
In the last few decades, many professional observers of American politics have worried that the constitutional system of democratic representation is failing. The convergence on intimations of failure is my starting point. It raises first-order normative concerns about the health of democratic representation in America that should worry all of us. The convergence also raises more theoretical questions about the nature and aims of democratic representation or, as I put it here, about standards of fair and effective representation. The first lecture begins by noting some stylized facts that purport to describe shortfalls from democratic representation. These include the phenomena of legislative gridlock, partisan polarization, unequal responsiveness by class and race, and partisan bias in legislative districting. Reflecting on these phenomena, I distinguish several kinds of failures that they implicate: of effectiveness, of congruence and responsiveness, and of fairness. In each case my aim is to grasp the normative grounds of judgments of failure explicit or implicit in the empirical literatures. On inspection, we see that the judgments of failure appeal to several distinct considerations of democratic political morality. It is difficult to see how these considerations might be brought within a single perspective that can make sense of them all. This prepares the way for the second lecture, where I try to sketch one way we might construct such a perspective.
Setting History in Motion
Authors: McDonald Daniel 
Published: October 2024

Abstract
This article examines the video essay in this issue, “Visualizing Resilience from the Periphery: Social Movements, Visual Archives, and the Megacity,” and the video essay as a form of historical argumentation. First, the article traces how the video essay reconstructs a visual lexicon that fostered resilience among social movements from the urban peripheries of South America’s most populous city, São Paulo, during Brazil’s civil-military dictatorship (1964–85) and the democratic transition that followed. Popular artists illustrated movement paraphernalia with hand-drawn images of diverse subjects, including urban landscapes, public life, neighborhood organizing, and open protest. The video essay assembles these dispersed illustrations as well as soundscapes and clips from films into distinct phases of a metanarrative connecting the rise of the megacity to collective social action. It subsequently disassembles those focal points to underscore the open-ended and iterative nature of visual argumentation. The article then underscores how the video essay as a form of peer-reviewable argumentation allows historians to creatively engage with a large corpus of visual imagery. It concludes by discussing issues inherent to the form, such as the difference between written and visual argumentation, citation practices, integration of text, translation of foreign languages, and the preservation of digital scholarship, among others.