bluuebunny/crossref_metadata_2025 huggingface dataset:
A computational fluid dynamics study of the impact of end effects on the Magnus effect and wake transition in the flow around a circular rotating cylinder with two free ends
Authors: Liu Qiliang , Gong Shuguang , Lu Haishan , Tang Fang , Liang Zhiwei
Published: January 2025

This paper investigates the influence of end effects on the Magnus effect and the three-dimensional unsteady flow behavior of a circular rotating cylinder with two free ends. The large eddy simulation method, using the Smagorinsky–Lilly model, is employed with a fixed aspect ratio of 10. The Reynolds number (Re) varies from 50 to 500, and the spin ratio (α) ranges from 0 to 5. Within the examined parameter space, eight instantaneous wake vortex modes are identified, including two steady flow modes, three unsteady periodic vortex modes, and two unsteady nonperiodic vortex modes. As α increases, the mean drag coefficient initially changes gradually, followed by a rapid increase, and eventually stabilizes or decreases. Two critical spin ratios are identified. As Re increases, the first critical spin ratio increases from 0.5 to 1, while the second decreases from 4.5 to 3.5. For the mean lift coefficient, a critical spin ratio is identified, decreasing from 4 to 3.5 as Re increases. The results indicate that the influence range of end effects on dynamic coefficients is primarily governed by the rotation effects, while Re also affects the values and distributions of dynamic coefficients, particularly at low Reynolds numbers.
Fluid compressibility related to migration on bubble dynamics
Authors: Xie Run-Ze , Zhang A-Man , Li Shi-Min
Published: January 2025

This work investigates the effects of fluid compressibility related to bubble migration. These effects are described based on a theoretical model for compressible bubble dynamics that considers phase transition and migration, as proposed by Zhang. Bubble experiments of different types are conducted to validate this theoretical model further. The model well captures experimental results near the wall and the free surface, illustrating that neglecting the compressibility effects of bubble migration results in overestimating the maximum radius and period during the second oscillating cycle. Disregarding the effects results in a higher peak migration kinetic energy during the second cycle but lower most of the time, which is related to the temperature, gas mass, and pressure inside the bubble. Furthermore, the discussion reveals that this migration-related compressibility can be enhanced by increasing the Mach number or vapor percentage.
Characteristics and mechanism of turbulent drag reduction in microgrooves in natural gas transportation pipelines
Authors: Wang Ruixuan , Li Xiaobin , Guo Liqi , Chen Xingyuan , Zhang Wen , Su Wentao
Published: January 2025

In order to reduce the resistance generated at the wall in the process of natural gas transport in the pipeline and, thus, improve the transport efficiency, a 426 mm diameter pipeline was used as the simulation object, and based on the turbulence reduction technology, by constructing a semi-circular groove structure with a longitudinal distribution of s (width) = h (depth) = 0.540 72 mm and alternating width semi-circular groove structures on the inner wall of the pipeline, and using the large eddy simulation method, the numerical simulation of methane gas is carried out under the working conditions of incoming flow velocity from 5 to 25 m/s. Based on the drag reduction effect at different Reynolds numbers, the evolution of vortex structure, the velocity strip structure at different y+ (dimensionless wall heights), and the root-mean square of the spreading, normal, and flow pulsation velocities, the near-wall region of the flow field characteristics of the smooth surface and the groove surface were compared and analyzed, so as to derive the mechanism of drag reduction in the groove. The results show that with the increase in the Reynolds number, the drag reduction rates of both types of microgroove structures showed a trend of first increasing and then decreasing, and the maximum drag reduction effects of 17.99% and 15.93% were observed when the s+ (dimensionless groove width) was between 16.96 and 20.84, respectively. The longitudinal microgroove structure has a drag reduction effect by suppressing the rising process of the flow vortices and the spreading motion of the vortex structure.
Utilizing Martian samples for future planetary exploration—Characterizing hazards and resources
Authors: Whetsel Charles , Levine Joel S. , Hoffman Stephen J. , Luckey Clare M. , Watts Kevin D. , Antonsen Erik L.
Published: January 2025

One of the most surprising and important findings of the first human landings on the Moon was the discovery of a very fine layer of lunar dust covering the entire surface of Moon along with the negative impacts of this dust on the well-being and operational effectiveness of the astronauts, their equipment, and instrumentation. The United States is now planning for human missions to Mars, a planet where dust can also be expected to be ubiquitous for many or most landing sites. For these missions, the design and operations of key hardware systems must take this dust into account, especially when related to crew health and safety. Improved understanding of Martian dust characteristics can inform its potential to also perform transport of microorganisms, both those inadvertently brought to Mars by the astronauts, or, if Martian microorganisms exist, the potential for their inadvertent return to Earth with the astronauts. Careful planning and design are needed to assure that future missions do not violate the United Nations Outer Space Treaty (1967) signed by all spacefaring nations. In this paper, we review the impact of lunar dust on the Apollo missions and identify several questions about dust in the atmosphere of Mars that may be answered by the curated samples that would be returned by the planned Mars Sample Return (MSR) Campaign. These answers would not only provide an opportunity to better understand the history of Mars but could also reduce uncertainty in charting the future of humanity’s exploration of the planet.
Mars Sample Return: From collection to curation of samples from a habitable world
Authors: McCubbin Francis M. , Farley Kenneth A. , Harrington Andrea D. , Hutzler Aurore , Smith Caroline L.
Published: January 2025

NASA’s Mars 2020 mission has initiated collection of samples from Mars’ Jezero Crater, which has a wide range of ancient rocks and rock types from lavas to lacustrine sedimentary rocks. The Mars Sample Return (MSR) Campaign, a joint effort between NASA and ESA, aims to bring the Perseverance collection back to Earth for intense scientific investigation. As the first return of samples from a habitable world, there are important challenges to overcome for the successful implementation of the MSR Campaign from the point of sample collection on Mars to the long-term curation of the samples on Earth. In particular, the successful execution of planetary protection protocols adds well-warranted complexity to every step of the process from the two MSR Program flight elements to the ground element at the sample receiving facility (SRF). In this contribution, we describe the architecture of the MSR Campaign, with a focus on infrastructure needs for the curation (i.e., the clean storage, processing, and allocation) of pristine Martian samples. Curation is a science-enabling and planetary protection-enabling activity, and the curation practices described in this contribution for the SRF and any long-term curation facility will enable the sample safety assessment, initial scientific investigations of the samples, and establish the MSR collection as a scientific resource that will enable generations of science and discovery through studies of the returned Mars samples. The planetary protection and curation processes established for MSR will provide critical insights into potential future sample return missions from other habitable worlds like Enceladus and Europa.
What we can learn about Mars from the magnetism of returned samples
Authors: Weiss Benjamin P. , Mansbach Elias N. , Maurel Clara , Sprain Courtney J. , Swanson-Hysell Nicholas L. , Williams Wyn
Published: January 2025

The Red Planet is a magnetic planet. The Martian crust contains strong magnetization from a core dynamo that likely was active during the Noachian period when the surface may have been habitable. The evolution of the dynamo may have played a central role in the evolution of the early atmosphere and the planet’s transition to the current cold and dry state. However, the nature and history of the dynamo and crustal magnetization are poorly understood given the lack of well-preserved, oriented, ancient samples with geologic context available for laboratory study. Here, we describe how magnetic measurements of returned samples could transform our understanding of six key unknowns about Mars’ planetary evolution and habitability. Such measurements could i) determine the history of the Martian dynamo field’s intensity; ii) determine the history of the Martian dynamo field’s direction; iii) test the hypothesis that Mars experienced plate tectonics or true polar wander; iv) constrain the thermal and aqueous alteration history of the samples; v) identify sources of Martian crustal magnetization and vi) characterize sedimentary and magmatic processes on Mars. We discuss how these goals can be achieved using future laboratory analyses of samples acquired by the Perseverance rover.
Pore pressure inhibits clustering of induced earthquakes in Western Canada
Authors: Li Bing Q.
Published: January 2025

Induced earthquakes are manifestations of highly heterogeneous distributions of effective stress changes imparted by anthropogenic activities such as hydraulic fracturing and wastewater injection. It is critical to disentangle the mechanisms behind these earthquakes to better assess seismic risk. Here, a clustering methodology is applied to a catalog of 21,536 induced earthquakes detected during a 36-d hydraulic stimulation program in Western Canada. The results reveal that clustered events nucleate at short recurrence times generally less than 6 min. Notably, the clustered events are not characterized by short interevent distances as seen in regional-scale studies. Numerical modeling reveals that earthquakes cluster preferentially in regions of significantly lower pore pressure change (

Δ
P

). Furthermore, clustered earthquakes exhibit significantly more chain-like topologies with decreasing

Δ
P

, in agreement with laboratory studies showing that fault materials transition to rate-strengthening behavior with increasing

Δ
P

. Proxy estimates for pore pressure change suggest these observations are consistent across Western Canada, and highlight the potential for significant temporal segmentation of induced earthquake processes.
High organofluorine concentrations in municipal wastewater affect downstream drinking water supplies for millions of Americans
Authors: Ruyle Bridger J. , Pennoyer Emily H. , Vojta Simon , Becanova Jitka , Islam Minhazul , Webster Thomas F. , Heiger-Bernays Wendy , Lohmann Rainer , Westerhoff Paul , Schaefer Charles E. , Sunderland Elsie M.
Published: January 2025

Wastewater receives per- and polyfluoroalkyl substances (PFAS) from diverse consumer and industrial sources, and discharges are known to be a concern for drinking water quality. The PFAS family includes thousands of potential chemical structures containing organofluorine moieties. Exposures to a few well-studied PFAS, mainly perfluoroalkyl acids (PFAA), have been associated with increased risk of many adverse health outcomes, prompting federal drinking water regulations for six compounds in 2024. Here, we find that the six regulated PFAS (mean = 7 to 8%) and 18 measured PFAA (mean = 11 to 21%) make up only a small fraction of the extractable organofluorine (EOF) in influent and effluent from eight large municipal wastewater treatment facilities. Most of the EOF in influent (75%) and effluent (62%) consists of mono- and polyfluorinated pharmaceuticals. The treatment technology and sizes of the treatment facilities in this study are similar to those serving 70% of the US population. Despite advanced treatment technologies, the maximum EOF removal efficiency among facilities in this work was <25%. Extrapolating our measurements to other large facilities across the United States results in a nationwide EOF discharge estimate of 1.0 to 2.8 million moles F y
−1
. Using a national model that simulates connections between wastewater discharges and downstream drinking water intakes, we estimate that the sources of drinking water for up to 23 million Americans could be contaminated above regulatory thresholds by wastewater-derived PFAS alone. These results emphasize the importance of further curbing ongoing PFAS sources and additional evaluations of the fate and toxicity of fluorinated pharmaceuticals.
Modeling expression of the research gap in text-based reading instruction
Authors: Ferdiansyah Sandi , Picard Michelle
Published: January 2025

This small-scale intervention aimed to prepare students to express a particular academic writing feature (the
research gap) through a structured intervention in corpus reading tasks. Four undergraduate (second year) students majoring in
English education participated in a collaborative corpus-based analysis of selected published articles. They then drew on the
corpus exemplars to develop their own gap statements. Data were collected from focus group interviews, students’ learning
journals, and learning artifacts. There were two key findings. First, the students indicated that corpus-based analysis helped
them become critical readers to recognize lexis used to show the research gap in the corpus-based database. Secondly, students
learned from the collocation patterns in the corpus to express the research gap in their own contexts. The study has practical
implications for language teaching demonstrating how corpus-based text-based language teaching can be a catalyst for students to
become active and critical meaning makers.
RACK1 MARylation regulates translation and stress granules in ovarian cancer cells
Authors: Challa Sridevi , Nandu Tulip , Kim Hyung Bum , Gong Xuan , Renshaw Charles W. , Li Wan-Chen , Tan Xinrui , Aljardali Marwa W. , Camacho Cristel V. , Chen Jin , Kraus W. Lee
Published: January 2025

Mono(ADP-ribosyl)ation (MARylation) is emerging as a critical regulator of ribosome function and translation. Herein, we demonstrate that RACK1, an integral component of the ribosome, is MARylated by the mono(ADP-ribosyl) transferase (MART) PARP14 in ovarian cancer cells. MARylation of RACK1 is required for stress granule formation and promotes the colocalization of RACK1 in stress granules with G3BP1, eIF3η, and 40S ribosomal proteins. In parallel, we observed reduced translation of a subset of mRNAs, including those encoding key cancer regulators (e.g., AKT). Treatment with a PARP14 inhibitor or mutation of the sites of MARylation on RACK1 blocks these outcomes, as well as the growth of ovarian cancer cells in culture and in vivo. To reset the system after prolonged stress and recovery, the ADP-ribosyl hydrolase TARG1 deMARylates RACK1, leading to the dissociation of the stress granules and the restoration of translation. Collectively, our results demonstrate a therapeutically targetable pathway that controls polysome assembly, translation, and stress granule dynamics in ovarian cancer cells.
Optimal weighted multi-scale entropy-energy ratio feature for rolling bearing degradation assessment
Authors: Shen Chen , Luo Jiesi , Jiang Pengli , Lin Guijuan , Zhang Shaohui
Published: January 2025

Extracting effective features from the full lifecycle data of mechanical equipment components and constructing a high-quality degradation assessment model are crucial in data-driven rolling bearing performance evaluation. Traditional single-feature methods often fail to capture the complex characteristics and subtle changes of faults comprehensively, leading to inadequate sensitivity and accuracy in early degradation detection. To address this issue, an adaptive optimal weighted multi-scale entropy-energy ratio feature extraction method is proposed and combined with a degradation model for evaluation. This method optimizes the relationship between multi-scale permutation entropy and root mean square through weighted parameters, integrating the advantages of both to enhance fault detection capabilities. Additionally, a weight parameter calculation method is introduced to ensure that features maintain good degradation expression under varying conditions. The features are then input into a common degradation model to generate the rolling bearing degradation curve. The effectiveness of the proposed method is validated using datasets from the NSFI/UCR Intelligent Maintenance Center (IMS) and Xi’an Jiaotong University-Changxing Shengyang Technology (XJTU-SY). Compared to features before optimization, the proposed method significantly improves early degradation point detection, monotonicity, correlation, and robustness.
Proposal for local SAR safety margin in pediatric neuro-imaging using 7 T MRI and parallel transmission
Authors: Dudysheva N , Luong M , Amadon A , Morel L , Touz N Le , Vignaud A , Boulant N , Gras V
Published: January 2025

Objective. Ultra-high field MRI with parallel transmission (pTx) provides a powerful neuroimaging tool with potential application in pediatrics. The use of pTx, however, necessitates a dedicated local specific absorption rate (SAR) management strategy, able to predict and monitor the peak local SAR (pSAR10g). In this work, we address the pSAR10g assessment for an in-house built 7 T 16Tx32Rx pediatric head coil, using the concept of virtual observation points (VOPs) for SAR estimation. Approach. We base our study on full-wave electromagnetic simulations performed on a database of 64 numerical anatomical head models of children aged between 4 and 16 years. We built VOPs on different subsets of this database of N= 2 up to 30 models, and cross-validated the pSAR10g prediction using non-intersecting subsets, each containing 30 models. We thereby propose a minimum anatomical safety factor (ASF) to apply to the VOP set to enforce safety, despite intersubject variability. Our analysis relies on the computation of the worst case SAR to VOP-SAR ratio, independent of the pTx RF excitation. Main results. The interpolation model provides that the minimum ASF decreases as

1
+
5.37
⋅

N

−
0.75

with N. Using all 64 models to build VOPs leads to an estimated ASF of 1.24 when considering the VOP validity for an infinite number of subjects. Significance. We propose a general simulation workflow to guide ASF estimation and quantify the trade-off between the number of numerical models available for VOP construction and the safety factor. The approach would apply to any simulation dataset and any pTx setup.
Forecasting random fatigue damage in laser-induced graphene interlayered fiberglass composites using long short-term memory
Authors: Chen Boyang , Childress Adam , Nasser Jalal , Fischer Michael , Sodano Henry A
Published: January 2025

Predicting the remaining life of composite materials under random dynamic loading is challenging due to the unpredictable nature of damage accumulation. Traditional fatigue prediction methods, which often assume sinusoidal loading, struggle to capture the complexities of random load profiles. This study advances fatigue life prediction by integrating deep learning techniques, including multilayer perceptrons (MLP) and long short-term memory (LSTM) neural networks, with laser-induced graphene (LIG) interlayered fiberglass composites. The piezoresistive properties of LIG, with resistance ranges between 100 and 350 Ω, enable effective in-situ tracking of fatigue damage. Results demonstrate that the LSTM network achieves superior accuracy, with R2 > 0.99 and RMSE values as low as 6×10-4 for predictions starting with just 20% of the data. Compared to MLP models, which require 40% of initial measurements to achieve similar accuracy, LSTM networks excel in capturing nonlinear damage propagation at later fatigue stages. These findings underscore the potential of LIG-based deep learning frameworks for closed-loop fatigue monitoring and reliable prognosis in dynamic environments.
Semiconductor-based direct current triboelectric nanogenerators and its application
Authors: Shi Xin , Wang Weiguo , Wang Jun , Li Jian , Chen Huamin
Published: January 2025

Triboelectric nanogenerator (TENG) utilizing tribovoltaic effect can directly produce direct current with high energy conversion efficiency, which expands their application in semiconductor devices and self-powered systems. This work comprehensively summarizes the recent developments in semiconductor-based direct current TENGs (SDC-TENGs), which hold significant promise for DC energy harvesting technologies and semiconductor systems. First, the tribovoltaic effect is elucidated, and SDC-TENGs are categorized into six types based on different triboelectric structures: metal−semiconductor (M−S), metal−insulator−semiconductor (M−I−S), semiconductor−semiconductor (S−S), semiconductor−insulator−semiconductor (S−I−S), liquid−semiconductor (L−S), and metal/semiconductor−liquid−semiconductor (M/S−L−S) contact devices. Subsequent sections detail the operational mechanisms, strengths, and limitations of each category. Additionally, this paper outlines the enhancement mechanisms of SDC-TENGs providing guidance and recommendations for performance improvement. The conclusion highlights potential application scenarios for various types of SDC-TENGs, outlining the prospective benefits and challenges. SDC-TENG technology is poised to drive revolutionary developments in semiconductor devices and self-powered systems.
Research on process-induced effect in 14-nm FinFET gate formation and digital unit optimization design
Authors: Yang Yafen , Xu Hang , Feng Tianyang , Guo Jianbin , Zhang David Wei
Published: January 2025

The advanced fin-shaped field-effect transistor (FinFET) technology offers higher integration density and stronger channel control capabilities, however, more complex process effects are also introduced which have significant influence on device performance. To address these issues, we complete a design-technology co-optimization (DTCO) focused on FinFET, including both process-induced effect during gate formation and corresponding digital unit optimization design. The 14 nm FinFET complementary metal oxide semiconductor (CMOS) technology is used to illustrate the sensitivity of transistor performance to process-induced effect, specifically the poly pitch effect (PPE) and cut poly effect (CPE). Predictive technology computer aided design (TCAD) simulations have been carried out to evaluate the transistor performance in advance. Based on the results, optimizations in digital unit design is proposed. Fall delay of the digital unit inverter is decreased by 0.7%, and the rise delay is decreased by 2.1%. For multiple selector (MUX2NV), the delay decreases by 4.64% for rise and 3.56% for drop, respectively.
Percolation in semicontinuum geometries
Authors: Jasna C K , Krishnadev V , Sasidevan V
Published: January 2025

We study percolation problems of overlapping objects where the underlying geometry is such that in

D
−

dimensions, a subset of the directions has a lattice structure, while the remaining directions have a continuum structure. The resulting semicontinuum problem describes the percolation of overlapping shapes in parallel layers or lanes with positional constraints for the placement of the objects along the discrete directions. Several semicontinuum percolation systems are analyzed like hypercuboids with a particular focus on 2D and 3D cases, disks, and parallelograms. Adapting the excluded volume arguments to the semicontinuum setting, we show that for the semicontinuum problem of hypercuboids, for fixed side-lengths of the hypercuboids along the directions in which a lattice structure is maintained, the percolation threshold is always independent of the side-lengths along the continuum directions. The result holds even when there is a distribution for the side-lengths along the continuum directions. Trends in the variation of the thresholds, as we vary the linear measure of the shapes along the continuum directions, are obtained for other semicontinuum models like disks and parallelograms in 2D. The results are compared with those of corresponding continuum and lattice models. For the 2D and 3D models considered, using Monte Carlo simulations, we verify the excluded volume predictions for the trends and numerical values of the percolation thresholds. Very good agreement is seen between the predicted numerical values and the simulation results. The semicontinuum setting also allows us to establish a connection between the percolation problem of overlapping shapes in 2D continuum and the triangular lattice. We also verify that the isotropy of the threshold for anisotropic shapes and standard percolation universality class is maintained in the semicontinuum setting.
On the Bisognano–Wichmann entanglement Hamiltonian of nonrelativistic fermions
Authors: Eisler Viktor
Published: January 2025

We study the ground-state entanglement Hamiltonian of free nonrelativistic fermions for semi-infinite domains in one dimension. This is encoded in the two-point correlations projected onto the subsystem, an operator that commutes with the linear deformation of the physical Hamiltonian. The corresponding eigenfunctions are shown to possess the exact same structure both in the continuum as well as on the lattice. Namely, they are superpositions of the occupied single-particle modes of the total Hamiltonian, weighted by the inverse of their energy as measured from the Fermi level, and multiplied by an extra phase proportional to the integrated weight. Using this ansatz, we prove that the Bisognano–Wichmann form of the entanglement Hamiltonian becomes exact, up to a nonuniversal prefactor that depends on the dispersion for gapped chains.
Ensemble inequivalence in Ising chains with competing interactions
Authors: Campa Alessandro , Hovhannisyan Vahan , Ruffo Stefano , Trombettoni Andrea
Published: January 2025

We study the effect of competing interactions on ensemble inequivalence. We consider a one-dimensional Ising model with ferromagnetic mean-field interactions and short-range nearest-neighbor (NN) and next-NN couplings which can be either ferromagnetic or antiferromagnetic. Despite the relative simplicity of the model, our calculations in the microcanonical ensemble reveal a rich phase diagram. The comparison with the corresponding phase diagram in the canonical ensemble shows the presence of phase transition points and lines which are different in the two ensembles. As an example, in a region of the phase diagram where the canonical ensemble shows a critical point and a critical end point, the microcanonical ensemble has an additional critical point and also a triple point. The regions of ensemble inequivalence typically occur at lower temperatures and at larger absolute values of the competing couplings. The presence of two free parameters in the model allows us to obtain a fourth-order critical point, which can be fully characterized by deriving its Landau normal form.
‘Resonant bars’ inspire a new search for quantum gravity
Authors: Akhouri Unnati
Published: January 2025

Researchers in the US and Sweden have proposed a new experiment to investigate whether gravity comes in discrete packages known as gravitons.
UK plans carbon capture revival
Authors: Allen Michael
Published: January 2025

Despite the UK government’s huge £22bn bet on carbon capture and storage, questions still remain over its feasibility, as Michael Allen reports.
Superconductivity theorist Leon Cooper dies aged 94
Authors: Banks Michael
Published: January 2025

The US condensed-matter physicist Leon Cooper, who shared the 1972 Nobel Prize for Physics, died on 23 October at the age of 94.
Consider the student
Authors: Vukusic Pete
Published: January 2025

Pete Vukusic says that students’ positive experiences when at university matter profoundly.
Around the world in 16 orbits
Authors: Gardner Kate
Published: January 2025

Kate Gardner reviews the novel Orbital by Samantha Harvey.
Ask me anything: Raghavendra Srinivas
Authors: Skipper Katherine
Published: January 2025

Raghavendra Srinivas is a research fellow in the Department of Physics and Balliol College at the University of Oxford, UK, and also works part-time for Oxford Ionics. His research focuses on using trapped ions for quantum information processing, quantum sensing and fundamental quantum optics. Srinivas was awarded Optica’s 2024 Theodor W Hänsch Prize in Quantum Optics, which recognizes impactful early career researchers working on optics-enabled quantum technologies.
Bioresorbable fibers for interstitial null-separation diffuse optical spectroscopy using fast temporal gating
Authors: Damagatla Vamshi , Boetti Nadia G , Di Sieno Laura , Pugliese Diego , Bargigia Ilaria , Janner Davide , Dalla Mora Alberto , Pifferi Antonio
Published: January 2025

Bioresorbable fibers are an exciting prospect as probes and implants to provide optical access to the human body. In this work, we demonstrate interstitial spectroscopy with bioresorbable fibers at null distance, using time-domain diffuse optics that disentangles absorption from scattering properties and probes the tissues up to a depth of a few cm around the fiber tips. We exploit a fast-gated single-photon avalanche diode with

>

55 dB of dynamic range to overcome the burst of ‘early’ photons hiding the information of absorption from deep tissues. We tested the absorption linearity—retrieving the water spectrum in the 700–950 nm range with

>

85% accuracy over two decades of absorption change—and verified the hypothesis of a scattering-independent absorption retrieval. Further, we were able to detect spectral changes at a distance of 1 cm from an inclusion embedded in a biological tissue. Time-domain diffuse optical spectroscopy with bioresorbable fibers could detect spectral changes without being affected by blood extravasation at the fiber tips and could help for long-term monitoring in tissue healing, thermal treatment, photodynamic therapy and ultimately, towards minimally invasive medical procedures.
A group of integral equations based on the thin-shell approximation approach for calculating current sharing between multiple layers of high-temperature superconducting tapes
Authors: Dai Xiang , Li Xiao-Fen
Published: January 2025

The second-generation high-temperature superconducting tapes are one of the most attractive materials for constructing high-field, large current application devices. To improve the thermal stability of the equipments, there is no insulating material between the tapes, which allows the current to be transferred between the tapes. However, electromagnetic calculations involving current sharing problems are still difficult because of the huge computational effort associated with the extremely high aspect ratio structure of the tape. Therefore, we improve the classical thin-shell approximation approach in this paper, and then propose a new group of 3D integral equations, which can be widely used to calculate the current sharing between multiple layers of high-temperature superconducting tapes. The highlight of the model is that it allows the use of 2D surface elements for all conductor domain meshes and no air domains, which significantly reduces the computational effort. The model can effectively calculate the current distribution in the tape-to-tape joints and no-insulation coils, and the validity of the model is verified by comparing with the H formulation and experimental data, respectively. Finally, the computational efficiency of the model is discussed as well as some key issues that exist. In the future, with the help of fast algorithms, the model will be more attractive than the finite element method for large-scale problems.
Normal forms for the sub-Riemannian exponential map of 𝔾_{𝛼}, 𝕊𝕌(2), and 𝕊𝕃(2)
Authors: Borza Samuël
Published: January 2025

The goal of this paper is to use singularity theory to find normal forms near the critical points of the sub-Riemannian exponential map. Three cases are studied: the

α
\alpha

-Grushin plane with fold singularities, and the special unitary group

SU
⁡
(
2
)

\operatorname {SU}(2)

and special linear group

SL
⁡
(
2
)

\operatorname {SL}(2)

with fold and saddle-like singularities. They serve as examples of different sub-Riemannian structures and the techniques presented can be applied to other contexts. The paper also includes a discussion of the implications of this approach, as well as open problems.
Spectral gap bounds on H-type groups
Authors: Carfagnini Marco , Gordina Maria
Published: January 2025

In this note we provide bounds on the spectral gap for the Dirichlet sub-Laplacians on

H
H

-type groups. We use probabilistic techniques and in particular small deviations of the corresponding hypoelliptic Brownian motion.
Disappearing Ink
Authors: O'Neill Eileen
Published: January 2025

As this chapter documents in great detail, women made numerous widely acknowledged contributions to philosophy in the seventeenth and eighteenth centuries; yet they disappeared from subsequent histories. This is “the problem of disappearing ink.” What accounts for this disappearance? The chapter considers a number of explanations: the move, following Kant, to “purify” philosophy of topics relating to gender; the fact that women often worked in an outmoded style; the prejudice that women were by nature unfit for philosophical work. Yet, while these help to explain why women’s work failed to play a central role in nineteenth-century (and later) histories, they do not explain their total erasure. The missing element concerns the threat that women philosophers posed to the hegemony of male authority following the French Revolution. The chapter also addresses the question: what model of historiography should the historian who seeks to rectify this erasure adopt? The chapter considers three models: rational reconstruction, historical reconstruction, and a variant of Hegelian Geistesgeschichte, arguing that a historical narrative loosely based on the latter is the preferred method for the feminist historian.
Feminist History of Philosophy
Authors: O'Neill Eileen
Published: January 2025

This chapter examines the role that feminism has played in the recovery and evaluation of women’s philosophical writings. It argues that how we understand the role of women in our histories depends on the methodology we use in doing the history of philosophy. “Pure” history of philosophy, the author maintains, allows for the reconstruction of women’s role in philosophical endeavors in terms of the motives, presuppositions, and argumentational strategies and standards of the past without the distorting influence of contemporary conceptions of what counts as “philosophy” or what counts as “feminist.” In addition, the historian of philosophy’s great debt to feminism is acknowledged. It is through feminism that we come to realize that women philosophers’ erasure from history is due to religious, economic, political, and social forces, which reinforce tradition, custom, and “common sense” in creating structural barriers to women’s taking their rightful place in our histories of philosophy.
Introduction to Observations on Experimental Philosophy
Authors: O'Neill Eileen
Published: January 2025

This chapter is an introduction to the natural philosophy of Margaret Cavendish, providing sufficient historical and biographical context for the reader to approach her Observations on Experimental Philosophy (1666). In Observations, Cavendish developed a non-Aristotelian alternative to the mechanical philosophy of the seventeenth century, one nonetheless consonant with strands of the new science. On her view, nature is an organism—a mixture of animate (self-moving) and inanimate matter. The chapter shows in detail how Cavendish’s conception of matter—at once panpsychist and panorganicist—informs her understanding of natural change, tracing the origins of her views to the Stoic’s doctrine of pneuma.
(Re)presentations of Eros
Authors: O'Neill Eileen
Published: January 2025

This chapter explores ways of representing women’s bodies erotically that lie beyond the male gaze. Focusing on feminist erotic art of the late 1980s (both erotica and pornography), it highlights representations that sexualize yet avoid objectification by emphasizing women’s agency. Whereas Jeanne Duval is “represented-as” (to adopt Nelson Goodman’s terminology) a lifeless doll in Manet’s sketch, the women depicted in the paintings of, for example, Margot Machida are represented-as erotically vigorous. The chapter also points to potential complications of this strategy, such as lesbian S/M portrayals of physical harm as erotic. The chapter suggests that by representing participants as agents, such depictions do not harm the participants as persons, despite a degree of physical pain that may be intimated.
Ambiguous Rationality
Authors: Williamson Timothy
Published: January 2025

This chapter applies the general approach of Chapter 9 to the special case of rationality. It distinguishes the rationality of a belief (complying with the evidence) from the rationality of a believer (being disposed to believe rationally), which in turn generates a derivative norm of belief (being what a rational believer would believe). Conflating primary and derivative norms of belief generates a form of internalism about epistemic justification, given that dispositions tend to be treated as internal. Such confusion is illustrated from the epistemological literature. The upshot of the discussion is to undermine the assumption that false beliefs can comply with the primary norm of rationality. A knowledge norm of belief remains defensible.
Four Schools in a Stratified Educational System
Authors: Xiang Xin
Published: January 2025

Chapter 2, Four Schools in a Stratified Educational System, paints richly textured portraits of the four schools and communities featured in Unequal Learning, describing the surroundings, facilities, people, and social dynamics of each school as well as the myriad relationships that shaped the author’s positionality. Red River Middle School is a rural public school serving the children of local farmers, including those who work in cities yet can’t afford to bring their children there. Yiping Experimental is a public school serving the children of workers, small business owners, and suburban farmers as well as a small number of teachers and civil servants in an emerging city in an impoverished region. Morningstar Academy is a low-cost, not-for-profit private school in Guangzhou primarily serving the children of migrant workers and migrant entrepreneurs shut out of public schools. Future Leader Academy is a prestigious metropolitan public school whose students mostly come from families of elite professionals, successful entrepreneurs, and government officials.
Municipal Authorities
Authors: Kudelia Serhiy
Published: January 2025

This chapter examines the chaotic and haphazard response of the local elites to the rising separatist challenge in their towns. It shows that rather than engaging in a coordinated effort to bargain with Kyiv, the municipal authorities in each town were trying to adjust their strategy to a local context. While initially they tried accommodating protesters through talks and rhetorical support for greater autonomy rights for the region, they dismissed more radical secessionist demands. Their strategies diverged substantially after the militants established coercive control over their towns. Most sought to remain in their positions and focus on municipal governance, but quickly faced the need to respond to militant requests. While some resigned in protest or fear of personal repercussions, others engaged in tacit or open collaboration. Yet others felt strong enough to sabotage separatist initiatives without explicitly rejecting them. Although Donbas avoided a major governance breakdown at the outset of the conflict, the administrative machinery in most towns was gradually coopted to advance the separatist cause.
A Different Vision
Authors: Mehta Uday Singh
Published: January 2025

This chapter considers the idea, central to Gandhi’s thinking, that there was something deeply misguided in conceiving of the turpitude of the empire in political terms, and from which the political articulation of the nation was the derivative and encompassing response. Because Gandhi did not subscribe to this view of the empire and the nationalist riposte that was predicated on it, he expresses both objections and an indifference to many of the concerns that were central to the nationalist aspirations. In particular he expresses an indifference, and sometimes pointed objections, to three concerns that were, and which in many ways remain, crucial to the nationalist project. The three concerns are the articulation of the grounds of a unitary people; the issue of how they are to be represented or how they would represent themselves; and the role of the state in mediating the relations among people and the linked, but distinct, issue of mediating among different communities that made up the people and the nation. That indifference stemmed from a very original conceptualization of the empire and it implied an equally original response to the empire. Among the things that followed from Gandhi’s demurral was a muted valuation of the importance of democratic political institutions including the challenges posed by the representation of the people.
Historical Memory and American Nonviolence
Authors: Danielson Leilah
Published: January 2025

The Christian radical A. J. Muste was the person most responsible for making Gandhian nonviolence a central feature of US political culture and was known worldwide as the foremost American peace activist, yet, in contrast to figures like Martin Luther King and Bayard Rustin, he remains largely invisible in American historical memory and has been neglected in the historical scholarship. This chapter explores this paradox by, firstly, tracing the origins, evolution, and influence of Muste’s theory of radical nonviolence and, secondly, analysing Muste’s involvement in the World Peace Brigade, a transnational collaborative effort by American, Indian, and British Gandhians in the late 1950s and early 1960s to apply nonviolence to the challenges of decolonization and the nuclear era. In so doing, the chapter highlights the hybrid roots, diverse genealogies, and transnational reach of American nonviolence. It further illustrates the similarities and differences between American and Gandhian nonviolence, showing that both traditions ultimately existed uneasily within the paradigm of the nation state, which limited their effectiveness in state-building projects, but it also speaks to their radical, transformative vision of human liberation.
On the Exchanges between Gandhi and Tagore
Authors: Kaviraj Sudipta
Published: January 2025

The chapter first sets out a distinction between two types of ‘theory’—systematic and critical—and suggests that we should place Gandhi’s theoretical reflections in the second category. The major part of the chapter analyses two types of differences between the two. In the first kind, they have different opinions, conclusions, or judgments about significant questions of social and political life; in the second kind, their opinions or judgments coincide, but they derive them from very different grounds or background assumptions. The chapter argues that we should attend to both types of differences, because that would offer us a truer assessment of the richness of the modern Indian tradition of social thought. Finally, the chapter discusses arguments about two distinct, but not conflicting, ideals of a good human life—one based on a predominantly ethical, the other on an aesthetic, orientation to the world.
On Sorcery of Peace and Nonviolence
Authors: Grinshpon Yohanan
Published: January 2025

How much of Mahatma Gandhi’s exceptional self-confidence and fearlessness of death is due to his connectedness with traditional yoga theory and practice? Mahatma Gandhi’s self-understanding as a yogin has been underrated. He was familiar with Patanjali’s Yoga Sūtra and practised yogic postures and breathing exercises under a mentor. He was also familiar—however reserved he may have been—with Patañjali’s theory of the unnatural powers (siddhis). Thus, for example, he highly appreciated Patañjali’s Yoga Sūtra 2.35 (‘for a yogin well established in the practice of ahiṃsā there ceases every kind of violence’), which seems the epitome of his essential strategy in life. However, a staunch optimist deeply rooted in the value of goodness, and a believer of the infinite power of moral behaviour, Gandhi was far from being a yogin and a naïve believer in the siddhis. Thus, traditional yoga theory and practice as well as his connectedness to ethics and moral values and power nourished his characteristic self-confidence and fearlessness.
Satyagraha in America—Gandhi, King, and the Politics of Fasting
Authors: Lal Vinay
Published: January 2025

This conversation with Rev. James M. Lawson (1928–2024), a principal architect of the American civil rights movement, author of the Nashville Student Movement and the sit-ins, and one of the founders of the Student Nonviolent Coordinating Committee (SNCC), revolves around the place of fasting in satyagraha. Gandhi has long been associated with fasting, and his deployment of fasting has been studied by activists the world over. The leaders of the American civil rights movement were careful and assiduous students of Gandhi’s thought, and Lawson conducted workshops on nonviolence for something like seven decades. Gandhi’s ideas were used widely by black Americans; nevertheless, though fasting was part of the Gandhian arsenal, American leaders and activists generally did not resort to fasting. In this conversation, Vinay Lal probes Lawson on the politics of fasting, Gandhi’s own use of fasting, the relationship of fasting to penitence, inner healing, and spiritual preparation, and Martin Luther King’s understanding of nonviolence and fasting.
On Being Impervious to the Discreet Charms of M. K. Gandhi
Authors: Suhrud Tridip
Published: January 2025

At 6.30 a.m. on 12 March 1930, M. K. Gandhi, accompanied by seventy-eight marchers, left the Sabarmati Ashram for Dandi, a coastal village in South Gujarat. He did not ever return to live in the ashram that he had created and nurtured since 1917. It is evident that the self-imposed exile applied not only to the Ashram but also increasingly to the city of Ahmedabad and Gujarat itself. In the remaining eighteen years of his life, Gandhi was to spend 301 days in Gujarat. His last visit to Ahmedabad was on 2 November 1936. His exile from Ahmedabad is reminiscent of a tap [penance]. He did not visit Gujarat after January 1942. If we understand something of this obvious turning away from Gujarat on the part of Gandhi, we might be able to capture something of the relationship that present-day Gujarat has with him. This chapter attempts in very broad strokes to capture the fraught cultural relationship that Gujarat shared with Gandhi—in his times and in ours.
Advocate Gandhi
Authors: DiSalvo Charles R
Published: January 2025

Society subjects public figures to scrutiny—usually contemporaneously. Some, like Thomas Jefferson and Martin Luther King, are also subject to withering posthumous criticism. Now, more than seventy years after his death, criticisms of Mohandas Gandhi’s work and person are arising with unusual force. These charges, including the charge of racism, disturb the picture the world has of Gandhi. This chapter sketches out a portrait of the Gandhi who is charged with racism and the position in society that he occupies. It offers a profile of the Gandhi who emerges after these attacks and suggests the position in society that the post-criticism Gandhi should occupy.