bluuebunny/crossref_metadata_2025_split huggingface dataset:
Animal loss and grief in zoos: Qualitative insights to inform organizational support for zoo professionals and volunteers
Authors: Nageotte Nichole Louise , Currin-McCulloch Jennifer , McDonald Shelby , Walker Abigail , Kogan Lori 
Published: February 2025

Abstract
Zoo professionals and volunteers frequently face significant emotional strain due to animal losses, yet structured organizational support for processing grief remains limited. This study explores the perspectives of US-based zoo professionals and volunteers on organizational responses to animal-related grief, aiming to identify areas to enhance support and foster a grief-affirming culture. Data were collected through an anonymous online survey with open-ended questions regarding organizational-level grief support. A purposive sample of 1695 zoo professionals and volunteers was recruited, with responses from 182 participants (135 animal care and health professionals, 12 volunteers, and 35 other staff) selected for qualitative analysis. Thematic analysis identified three primary themes: creating an organizational culture supportive of grief expression, increasing organizational response mechanisms and resources, and enriching human resource policies to support grieving zoo professionals and volunteers. Many participants reported that insufficient grief support led to feelings of isolation, shame, and burnout. Findings underscore the importance for zoos to prioritize the development of comprehensive grief-affirming policies, including grief training for leadership, expanded access to mental health resources, and development of communication protocols for timely, compassionate responses to animal loss. These recommendations aim to foster empathetic organizational cultures that support staff and volunteer well-being and effective animal care.
Evaluation and Suppression of Vibrational Noise for Cryogenic Surface Electrode Ion Traps
Authors: Qin Qingqing , Ou Baoquan , Wu Wei , Xie Yi , Chen Ting , Wu Chunwang , Chen Pingxing 
Published: February 2025

Abstract
Cryogenic ion traps offer substantial benefits over their room-temperature counterparts, particularly in terms of stable ion confinement and cooling. However, this technological growth introduces a significant challenge: the generation of additional vibrational noise. This noise is most pronounced during the compression and expansion phases of the Gifford-McMahon cyclic refrigerator (GMCR) and stems from the mechanical operations of the cold head. Residual vibrational noise can modulate the Rabi oscillation frequency, thereby compromising the fidelity of the quantum logic gate. In this study, we provide a quantitative assessment of the impact of residual vibrational noise and introduce an innovative strategy for its mitigation. This strategy was designed to reduce superimposed potential fluctuations within a cryogenic surface electrode ion trap (CSEIT). The measured residual vibrational noise was used for real-time feedback control. Addressing the inverse determination of the compensating potential for a stable superimposed trapping potential is an inherently ill-posed problem given the known measurement noise results. By applying quadratic programming, we numerically calculated the optimal time series for the compensation potential. An ensemble of these compensation voltages was applied in real time to the static compensation electrodes. Although this method still in the stage of theory, we believe that it could effectively suppress the translation induced by vibrational noise and foster the creation of a stable superimposed harmonic potential well. The deployment of such a technique is expected to substantially improve the accuracy of quantum operations, thereby fueling the evolution of quantum technologies.
Kerr metric from two commuting complex structures
Authors: Krasnov Kirill , Shaw Adam 
Published: February 2025

Abstract
The main aim of this paper is to simplify and popularise the construction from the 2013 paper by Apostolov, Calderbank, and Gauduchon, which (among other things) derives the Pleban ́ski- Demian ́ski family of solutions of GR using ideas of complex geometry. The starting point of this construction is the observation that the Euclidean versions of these metrics should have two different commuting complex structures, as well as two commuting Killing vector fields. After some linear algebra, this leads to an ansatz for the metrics, which is half-way to their complete determination. Kerr metric is a special 2-parameter subfamily in this class, which makes these considerations directly relevant to Kerr as well. This results in a derivation of the Kerr metric that is self-contained and elementary, in the sense of being mostly an exercise in linear algebra.
Spurious solar-wind effects on acceleration noise in LISA pathfinder
Authors: Yang Arnold Tianyi , Desiderio-Sloane Indie , Meadors Grant David 
Published: February 2025

Abstract
Spurious solar-wind effects are a potential noise source in future Laser Interferometer Space Antenna (LISA) measurements. One noise coupling mechanism is constrained by estimating solar-wind effects on acceleration noise in LISA Pathfinder (LPF). While LISA is designed for drag-free differential measurement, predicting the realistic impact both bounds the operational environment and assesses whether LISA could provide serendipitous space-weather observations. Data from NASA’s Advanced Composition Explorer (ACE), situated at the L1 Lagrange point, serves as a reliable source of solar-wind data. The data sets are compared over the 114-day time period from March 1, 2016 to June 23, 2016. This period gives the longest readily-available open data set, without interference from other commissioning activities. To evaluate space weather effects, the data from both satellites are formatted, gap-filled/interpolated, and Fast-Fourier Transformed for amplitude spectral density and coherence comparisons. Solar wind effects are not seen in a coherence plot between LPF and ACE; modest coherence in the planned LISA observational frequency band can be attributed to chance. This result indicates that measurable correlation due to solar-wind acceleration noise over 3-month timescales will be a negligible noise source. LISA is unlikely to inform solar wind measurements routinely. Another source of noise from the sun, solar radiation pressure, is estimated to impart greater acceleration noise, but has yet to be analyzed.
Accelerating Multilevel Markov Chain Monte Carlo Using Machine Learning Models
Authors: Reddy Sohail , Fairbanks Hillary 
Published: February 2025

Abstract
This work presents an efficient approach for accelerating multilevel Markov Chain Monte Carlo (MCMC) sampling for large-scale problems using low-fidelity machine learning models. While conventional techniques for large-scale Bayesian inference often substitute computationally expensive high-fidelity models with machine learning models, thereby introducing approximation errors, our approach offers a computationally efficient alternative by augmenting high-fidelity models with low-fidelity ones within a hierarchical framework. The multilevel approach utilizes the low-fidelity machine learning model (MLM) for inexpensive evaluation of proposed samples thereby improving the acceptance of samples by the high-fidelity model. The hierarchy in our multilevel algorithm is derived from geometric multigrid hierarchy. We utilize an MLM to accelerate the coarse level sampling. Training machine learning model for the coarsest level significantly reduces the computational cost associated with generating training data and training the model. We present an MCMC algorithm to accelerate the coarsest level sampling using MLM and account for the approximation error introduced. We provide theoretical proofs of detailed balance and demonstrate that our multilevel approach constitutes a consistent MCMC algorithm. Additionally, we derive the expression for cost reduction due to machine learning model to facilitate cost analysis of the hierarchical sampling algorithm. Our technique is demonstrated on a standard benchmark inference problem in groundwater flow, where we estimate the probability density of a quantity of interest using a four-level MCMC algorithm. Our proposed algorithm accelerates multilevel sampling by a factor of two while achieving similar accuracy compared to sampling using the standard multilevel algorithm.
A semi-analytic estimate for the effective sound speed counterterm in the EFTofLSS
Authors: Nascimento Caio , Jamieson Drew , McQuinn Matthew , Loverde Marilena 
Published: February 2025

Abstract
The Effective Field Theory of Large Scale Structure (EFTofLSS) has found tremendous success as a perturbative framework for the evolution of large scale structure, and it is now routinely used to compare theoretical predictions against cosmological observations. The model for the total matter field includes one nuisance parameter at 1-loop order, the effective sound speed, which can be extracted by matching the EFT to full N-body simulations. In this work we first leverage the Layzer-Irvine cosmic energy equation to show that the equation of state can be exactly computed with knowledge of the fully nonlinear power spectrum. When augmented with separate universe methods, we show one can estimate the effective sound speed. This estimate is in good agreement with simulation results, with errors at the few tens of percent level. We apply our method to investigate the cosmology dependence of the effective sound speed and to shed light on what cosmic structures shape its value.
Warm Hawking relics from
primordial
black hole domination
Authors: Shallue Christopher J. , Muñoz Julian B. , Krnjaic Gordan Z. 
Published: February 2025

Abstract
We study the cosmological impact of warm, dark-sector relic particles produced as Hawking
radiation in a primordial-black-hole-dominated universe before big bang nucleosynthesis. If these
dark-sector particles are stable, they would survive to the present day as Hawking relics
and modify the growth of cosmological structure. We show that such relics are produced
with much larger momenta, but in smaller quantities than the familiar thermal relics considered in
standard cosmology. Consequently, Hawking relics with keV–MeV masses affect the growth of
large-scale structure in a similar way to eV-scale thermal relics like massive neutrinos. We
model their production and evolution, and show that their momentum distributions are broader than
comparable relics with thermal distributions. Warm Hawking relics affect the growth of
cosmological perturbations and we constrain their abundance to be less than 2% of the dark
matter over a broad range of their viable parameter space. Finally, we examine how future
measurements of the matter power spectrum can distinguish Hawking relics from thermal particles.
Gravitational radiation from binary systems in unimodular gravity
Authors: Chakraborty Indranil , Jana Soumya , Mohanty Subhendra 
Published: February 2025

Abstract
Unimodular gravity (UG) is classically considered identical to General Relativity (GR). However, due to restricted diffeomorphism symmetry, the Bianchi identites do not lead to the conservation of energy-momentum tensor. Thus, the conservation of energy-momentum tensor needs to be separately assumed in order to reconcile with GR. Relaxing this assumption, one finds that the conservation violation can lead to differences with GR, which can be subsequently examined in astrophysical and cosmological scenarios. To this end, we examine the predictions of UG in the context of binary systems emitting gravitational radiation. Primarily, we show how the field equations involve a diffusion function which quantifies the measure of non-conservation. Due to this violation, the dispersion relation is modified. Incorporating these changes, we provide an expression for the energy loss by the binaries, which reduces to Peters-Mathews result in the GR limit. Using binary pulsar data, we constrain the theory parameter ζ (which signifies non-conservation) by determining the rate of orbital decay. The strongest constrain on ζ comes out to be |ζ|≤ 5× 10-4 which is better by an order of magnitude than an existing equivalent constraint coming from the tidal deformability of the neutron stars.
Charged binaries in gravitational tides
Authors: Grilli Elisa , Orselli Marta , Pereñiguez David , Pica Daniele 
Published: February 2025

Abstract
Next-generation low-frequency interferometers are expected to detect binary systems near
supermassive black holes, where tidal effects can alter significantly the binary's motion. This
motivates a broader investigation of how external gravitational fields influence the dynamics of
physical systems. In this work, we consider a charged black hole binary system subject to a
gravitational tide. We first construct a stationary gravitational tide acting on a dyonic
Reissner-Nordström black hole and, focusing on the extreme mass-ratio limit, we analyze the motion
of a test particle. By calculating the particle's secular Hamiltonian, we obtain the ISCO and
light ring tidal shifts in terms of explicit functions of the binary's parameters. Our results
show that tidal corrections are suppressed as the black hole's charge increases, but they persist
in the extremal limit yielding a finite contribution. This work paves the way towards studying
tidal effects on other charged systems, such as topological stars.
Propagation of Hermite cosh Gaussian laser beam in free electron laser device under upward plasma density ramp
Authors: Anshal Lenic , Kant Niti , Azad Taruna , Rajput Jyoti , Kamboj Oriza 
Published: February 2025

Abstract
This paper analyses the propagation of a Hermite cosh Gaussian laser beam into the free electron laser (FEL) device inside a plasma with an upward density ramp. The dispersion relation is derived using linear fluid theory. A detailed analysis of its characteristics, such as changes in growth rate attributing to both Compton and Raman regimes and the energy exchange efficiency has been investigated. Further, the growth rate characteristics have been observed for varying decentered parameter and mode index values. The result analysis shows, enhanced energy transfer at high plasma densities and an increase in frequency of radiation emission in the Raman regime, attributable to increased scattering and interaction facilitated by the upward plasma density ramp. The increase in normalized energy gain with beam voltage highlights the improved energy transfer efficiency in the FEL, emphasizing the value of higher voltages for maximum energy gain. This paves way to efficient interaction and improved tunability, enabling the operation of FELs at increased beam voltages, resulting in the generation of high-frequency radiation.
Platinum as a first mirror material for fusion applications: a comparison with rhodium
Authors: Dmitriev Artem M. , Wang Youpeng , Sousa Tomás C. , Marot Laurent , Moser Lucas , Meyer Ernst 
Published: February 2025

Abstract
The metallic first mirrors (FMs) of ITER optical diagnostics will face erosion caused by particles from the fusion plasma, as well as redeposition of materials originating from the first wall. Both processes can degrade their reflectivity over time. In vacuo plasma cleaning is planned to restore their optical properties. Several mirror materials were tested for the FM application. Currently, mirrors based on nanocrystalline rhodium (Rh) coatings or single crystal molybdenum (Mo) are considered as the mainstream approach. However, previous research indicates that repetitive cleaning of nanocrystalline mirrors can cause surface patterning, which negatively impacts their optical performance. Additionally, FMs are vulnerable to in-vessel coolant leaks, which could severely degrade their optical properties. Literature shows that exposing Rh mirrors to steam results in the formation of a thin layer of Rh oxide and the development of voids in the top 1 µm of the coating. Despite this, plasma cleaning has been shown to restore the pristine reflectivity of the mirrors. This paper discusses the potential of utilizing platinum (Pt) as an FM material. Pt and Rh were subjected to cyclic plasma cleaning and steam ingress tests, after which their morphology and optical properties were measured and analyzed using XPS, SEM, FIB and spectrophotometry. Additionally, the neutron-induced transmutation of Pt and Rh was assessed with respect to ITER and DEMO irradiation scenarios.
Divergent patterns and determinants of resistance and resilience in short and tall forests across global drylands
Authors: He Xiao , Dong Xiaoxue , Li Xuan , Chen Ning , Zhao Changming 
Published: February 2025

Abstract
Forests play a crucial role in mitigating climate change, and global afforestation initiatives are in full swing, with drylands having great potential for afforestation. However, many dryland afforestation projects lead to short forests with significantly lower canopy height than their typical height. Meanwhile, the potentially increasing probability of drought threatens short forests and their tall counterparts. Yet, it remains largely unclear whether these short forests respond differently to drought compared to tall forests. Here, we used the K-means clustering method to classify global dryland forests into short and tall forests. We found significant differences in drought resistance and resilience between short and tall forests, with tall forests demonstrating higher resistance and short forests having higher resilience. Furthermore, our study indicated that in severe and extreme drought conditions, resistance and resilience of short forests were more likely influenced by climatic factors than tall forests, which were more likely affected by soil factors. These findings suggest that climatic monitoring should be intensified for short forests, and post-drought management should be strengthened for tall forests to enhance their persistence under climate change.
Social inequalities in exposure to heat stress and related adaptive capacity: A systematic review
Authors: Slesinski S. Claire , Matthies-Wiesler Franziska , Breitner Susanne , Gussmann Geronimo , Schneider Alexandra 
Published: February 2025

Abstract
Background: Extreme heat is an important public health concern, and heat stress exposure and related adaptive capacity are not equally distributed across social groups. We conducted a systematic review to answer the question: What is the effect of social disadvantage on exposure to heat stress and related adaptive capacity in the general population? &#xD;Methods: We systematically searched for peer-reviewed journal articles that assessed differences in heat stress exposure and related adaptive capacity by social factors that were published between 2005 and 2024. One author screened all records and extracted data; a second author screened and extracted 10% for validation. Synthesis included the identification and description of specific social groups unequally exposed to heat stress and with lower adaptive capacity. We assessed European studies for the potential risk of bias. &#xD;Results: We identified 123 relevant publications. Subjective heat stress appeared in 18.7% of articles, objective heat stress in 54.5%, and adaptive capacity in 54.5%. Nearly half came from North America (47.2%), 22.8% from Asia, and 17.1% from Europe. Publishing increased from zero articles in 2005 to 21 in 2023. Most studies considered socioeconomic status (SES) (78.8%), and many considered age (50.4%), race/ethnicity (42.3%), and sex/gender (30.1%). The studies showed that lower-SES populations, young people, unemployed people, those in outdoor and manual occupations, and minorities are generally more exposed to heat stress and have lower adaptive capacity. European studies generally have a low or moderate risk of bias. &#xD;Conclusion: Social inequalities in heat stress exposure and related adaptive capacity have been documented globally. In general, socially disadvantaged populations are more exposed to heat stress and have lower adaptive capacity. These social inequalities are context-dependent, dynamic, multi-dimensional, and intersectional. It is essential to consider social inequalities during heat-health action planning and when developing and implementing climate change adaptation policies and interventions. &#xD;
Recrystallization induced by heat treatment regulates the anisotropic behavior of CoCrMo alloys fabricated by laser powder bed fusion
Authors: Dai Lijin , Song Changhui , Fu Houxiong , Chen Hongyi , Yan Zhongwei , Liu Zibin , Li Renyao , Wang Anming , Yang Yongqiang , Yu Jia-Kuo 
Published: February 2025

Abstract
The CoCrMo alloys fabricated by the laser powder bed fusion (LPBF) exhibit significant anisotropy due to the characteristics of layer-by-layer manufacturing. This study investigated the microstructural evolution and mechanical properties of CoCrMo alloys in both as-printed and heat-treated states. The results demonstrated that the elongation was 19.1% in the tensile direction parallel to the building direction, compared to only 9.3% in the perpendicular direction, showing a difference of over 100%. After solution heat treatment at 1150 °C for 1 h followed by annealing heat treatment at 450 °C for 0.5 h, the ultimate tensile strength and elongation nearly equalized, reaching 906.1 MPa, 20.2% and 879.2 MPa, 17.9%, respectively. Further characterization indicated that the anisotropy was mainly caused by grain morphology. Solution treatment-induced recrystallization refined coarse columnar grains into equiaxed grains that accommodated orientation-related stresses, which tentatively achieves microstructural and mechanical homogeneity. Subsequent low-temperature annealing broke the trade-off between the strength and ductility while further promoting the isotropy. At this stage, the mechanical properties were strengthened by the synergistic interaction of nanoscale annealing twins and martensitic laths. This study provided valuable insights for optimizing the isotropic behavior in LPBF-fabricated CoCrMo alloys.
The Ark of Indiana Jones and Other Cinematic Arks
Authors: McGeough Kevin M 
Published: February 2025

Abstract
Chapter 6 offers an overview of the Ark in Hollywood film. It explores how Raiders of the Lost Ark and the Indiana Jones franchise have fundamentally altered how the general public thinks about the Ark. It discusses the genre of the action film and how the Ark is reinterpreted as a “MacGuffin,” something to be chased in a film. The chapter pivots, then, to a discussion of the other cinematic genre in which the Ark has most frequently appeared: the biblical epic. The arguments made in biblical epics are examined, with an eye to understanding the messages that audiences take away about the Ark, the Bible, and society in general, when they watch these films.
Aliens, Radios, and Conspiracies
Authors: McGeough Kevin M 
Published: February 2025

Abstract
This chapter offers a discussion of fake quests for the Ark, ancient aliens, and other infotainment about the Ark. It covers the main streams of pseudoarchaeological thinking related to the Ark, that there is some kind of conspiracy to hide the Ark, that it has some relation to aliens, or that it reflects some kind of advanced ancient technology now forgotten to the world. It discusses the types of claims pseudoscholars make related to the Ark as well as the logical fallacies and rhetorical techniques embedded in their arguments. The chapter ends with a discussion of why people are drawn to these kinds of ideas and why they are problematic.