bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phase transitions of civil unrest across countries and time
Authors: Braha Dan 
Published: April 2024

AbstractPhase transitions, characterized by abrupt shifts between macroscopic patterns of organization, are ubiquitous in complex systems. Despite considerable research in the physical and natural sciences, the empirical study of this phenomenon in societal systems is relatively underdeveloped. The goal of this study is to explore whether the dynamics of collective civil unrest can be plausibly characterized as a sequence of recurrent phase shifts, with each phase having measurable and identifiable latent characteristics. Building on previous efforts to characterize civil unrest as a self-organized critical system, we introduce a macro-level statistical model of civil unrest and evaluate its plausibility using a comprehensive dataset of civil unrest events in 170 countries from 1946 to 2017. Our findings demonstrate that the macro-level phase model effectively captures the characteristics of civil unrest data from diverse countries globally and that universal mechanisms may underlie certain aspects of the dynamics of civil unrest. We also introduce a scale to quantify a country’s long-term unrest per unit of time and show that civil unrest events tend to cluster geographically, with the magnitude of civil unrest concentrated in specific regions. Our approach has the potential to identify and measure phase transitions in various collective human phenomena beyond civil unrest, contributing to a better understanding of complex social systems.
A computational topology-based spatiotemporal analysis technique for honeybee aggregation
Authors: Gharooni-Fard Golnar , Byers Morgan , Deshmukh Varad , Bradley Elizabeth , Mayo Carissa , Topaz Chad M. , Peleg Orit 
Published: April 2024

AbstractA primary challenge in understanding collective behavior is characterizing the spatiotemporal dynamics of the group. We employ topological data analysis to explore the structure of honeybee aggregations that form during trophallaxis, which is the direct exchange of food among nestmates. From the positions of individual bees, we build topological summaries called CROCKER matrices to track the morphology of the group as a function of scale and time. Each column of a CROCKER matrix records the number of topological features, such as the number of components or holes, that exist in the data for a range of analysis scales, at a given point in time. To detect important changes in the morphology of the group from this information, we first apply dimensionality reduction techniques to these matrices and then use classic clustering and change-point detection algorithms on the resulting scalar data. A test of this methodology on synthetic data from an agent-based model of honeybees and their trophallaxis behavior shows two distinct phases: a dispersed phase that occurs before food is introduced, followed by a food-exchange phase during which aggregations form. We then move to laboratory data, successfully detecting the same two phases across multiple experiments. Interestingly, our method reveals an additional phase change towards the end of the experiments, suggesting the possibility of another dispersed phase that follows the food-exchange phase.
Once in a blue stream
Authors: Martínez-Delgado David , Roca-Fàbrega Santi , Gil de Paz Armando , Erkal Denis , Miró-Carretero Juan , Makarov Dmitry , Voggel Karina T. , Leaman Ryan , Bolchin Walter , Pearson Sarah , Donatiello Giuseppe , Rubtsov Evgenii , Akhlaghi Mohammad , Gomez-Flechoso M. Angeles , Raji Samane , Lang Dustin , Block Adam , Gallego Jesus , Carrasco Esperanza , García-Vargas María Luisa , Iglesias-Páramo Jorge , Pascual Sergio , Cardiel Nicolas , Pérez-Calpena Ana , Castillo-Morales Africa , Gómez-Alvarez Pedro 
Published: April 2024

Aims. In this work we study the striking case of a narrow blue stream with a possible globular cluster-like progenitor around the NGC 7241 galaxy and its foreground dwarf companion. We want to figure out if the stream was generated by tidal interaction with NGC 7241 or if it first interacted with the foreground dwarf companion and later both fell together toward NGC 7241.
Methods. We used four sets of observations, including a follow-up spectroscopic study of this stream based on data taken with the MEGARA instrument at the 10.4 m Gran Telescopio Canarias using the integral field spectroscopy mode, the Mount Lemmon 0.80 m telescope, the Telescopio Nazionale Galileo, the DESI Imaging Legacy surveys, and GALEX archival data. We also used high-resolution zoomed-in cosmological simulations.
Results. Our data suggest that the compact object we detected in the stream is a foreground Milky Way halo star. Near this compact object we detect emission lines overlapping a less compact, bluer, and fainter blob of the stream that is clearly visible in both ultraviolet and optical deep images. From its heliocentric systemic radial velocity derived from the [O III]λ5007 Å lines (Vsyst = 1548.58 ± 1.80 km s−1) and new UV and optical broadband photometry, we conclude that this overdensity could be the actual core of the stream, with an absolute magnitude of Mg ∼ −10 and a g − r = 0.08  ±  0.11, consistent with a remnant of a low-mass dwarf satellite undergoing a current episode of star formation. From the width of the stream and assuming a circular orbit, we calculate that the progenitor mass can be typical of a dwarf galaxy, but it could also be substantially lower if the stream is on a very radial orbit or if it was created by tidal interaction with the companion dwarf instead of with NGC 7241. These estimates also suggest that this is one of the lowest mass streams detected to date beyond the Local Group. Finally, we find that blue stellar streams containing star formation regions are commonly predicted by high-resolution cosmological simulations of galaxies lighter than the Milky Way. This scenario is consistent with the processes explaining the bursty star formation history of some dwarf satellites, which are followed by a gas depletion and a fast quenching once they enter within the virial radius of their host galaxies for the first time. Thus, it is likely that the stream’s progenitor is undergoing a star formation burst comparable to those that have shaped the star formation history of several Local Group dwarfs in the last few gigayears.
Age-Dependent Detection of Atrial Fibrillation with Implantable Cardiac Monitors in Patients with Cryptogenic Stroke
Authors: Uhe Tobias , Keilitz Janina , Berrouschot Jörg , Wachter Rolf 
Published: April 2024

Background Continuous monitoring using implantable cardiac monitors (ICMs) results in atrial fibrillation (AF) detection rates of up to 30% in patients with cryptogenic stroke (CS). Although higher age is an independent risk factor for AF, there are no age-specific recommendations for the implantation of ICM.
Objective The aim of this study was to analyze age-related AF rates in patients with CS and continuous rhythm monitoring, to determine the rates of oral anticoagulation (OAC) and recurrent cerebrovascular events (stroke or transient ischemic attack) in patients with ICM-detected AF, and to describe the temporal relationship of AF detection and recurrent cerebrovascular events.
Methods In this observational study, patients with CS provided with ICMs were systematically followed. All patients underwent 72-hour electrocardiography monitoring, transcranial Doppler ultrasound, and transthoracic echocardiography prior to ICM insertion. Follow-up included a regular outpatient presentation every 3 months with medical history, physical examination, and interrogation of the ICM.
Results One-hundred eighty-six patients (mean age: 65 ± 12 years, 54% female) were included in this analysis. AF was detected in 6, 27, 56, and 65% (p < 0.001) of patients aged less than 60, 60 to 69, 70 to 79, and more than or equal to 80 years, respectively. All patients with AF under 60 years had an impaired left ventricular systolic function. OAC was initiated in 85% of the patients with AF. Recurrent cerebrovascular events occurred in 34 patients of whom 14 had a diagnosis of AF. In nine patients, AF was diagnosed before the occurrence of a recurrent cerebrovascular event.
Conclusion AF prevalence increased with age and was absent in CS patients younger than 60 years and with preserved left ventricular ejection fraction. The temporal relationship of AF and recurrent cerebrovascular events was weak.
How popularising higher education affects economic growth and poverty alleviation: empirical evidence from 38 countries
Authors: Li Jian , Xue Eryong , Wei Yukai , He Yunshu 
Published: April 2024

AbstractThe popularisation of higher education supports UNESCO’s aim of developing inclusive and equitable quality education to achieve the fourth Sustainable Development Goal. However, the effect of popularising higher education on economic growth and poverty alleviation remains unexplored. Therefore, this study investigated the effects of higher education and adult education within populations (popularisation of higher education) on economic growth (gross domestic product; GDP) and the poverty line using panel data from 38 countries. OLS and quantile regression were performed using data for the period 1995–2021 extracted from the OECD and World Bank databases. The results showed that the population segments with higher education had a significantly positive impact on GDP growth. Moreover, an increased proportion of the population with higher education, of working age, was found to be a contributing factor to GDP growth. Popularising higher education also played a positive role during the initial stage of social and economic development. This study also highlighted that popularising higher education play a key role to influence a country’s educational development and scientific and technological innovation drives the deepening of a country’s economy. It suggested that both national and local governments worldwide should pay much attention to the popularisation degree of higher education to greatly improve the innovative ability of talents and scientific and technological innovation in higher education for both the economic growth and poverty alleviation.
Mitochondrial DNA polymorphism of a triploid form of Fasciola in Japan
Authors: Itagaki T. , Honnami M. , Ito D. , Ito K. , Tsutsumi K. , Terasaki K. , Shibahara T. , Noda Y. 
Published: April 2024

AbstractMitochondrial DNA polymorphism was characterized in a triploid form of Fasciola found in Japan in comparison with F. hepatica, F. gigantica and Korean Fasciola worm. Seventy worms of Fasciola from Japan, three of F. hepatica from Uruguay and Australia, two of F. gigantica from Thailand and one of Fasciola from Korea were used in the study. Mitochondrial DNA polymorphism was detected by restriction fragment length polymorphism (RFLP) using eight restriction enzymes, BamH I, Bgl II, Dra I, EcoR I, EcoR V, Hind III, Mfl I and Sca I. Three different types (types 1, 2 and 3) were detected from 76 Fasciola worms used in the study. Eight of 70 Japanese worms were categorized in type 2 (F. gigantica type), and the remaining 62 were in type 3 (F. hepatica type).
Algebraic classification of 2+1 geometries: a new approach
Authors: Papajčík Matúš , Podolský Jiří 
Published: April 2024

AbstractWe present a convenient method of algebraic classification of 2+1 spacetimes into the types I, II, D, III, N and O, without using any field equations. It is based on the 2+1 analogue of the Newman–Penrose curvature scalarsΨAof distinct boost weights, which are specific projections of the Cotton tensor onto a suitable null triad. The algebraic types are then simply determined by the gradual vanishing of such Cotton scalars, starting with those of the highest boost weight. This classification is directly related to the specific multiplicity of the Cotton-aligned null directions and to the corresponding Bel–Debever criteria. Using a bivector (that is 2-form) decomposition, we demonstrate that our method is fully equivalent to the usual Petrov-type classification of 2+1 spacetimes based on the eigenvalue problem and determining the respective canonical Jordan form of the Cotton–York tensor. We also derive a simple synoptic algorithm of algebraic classification based on the key polynomial curvature invariants. To show the practical usefulness of our approach, we perform the classification of several explicit examples, namely the general class of Robinson–Trautman spacetimes with an aligned electromagnetic field and a cosmological constant, and other metrics of various algebraic types.
DECAF cross-device characterization of tokamak disruptions indicated by abnormalities in plasma vertical position and current
Authors: Zamkovska V. , Sabbagh S.A. , Tobin M. , Berkery J.W. , Riquezes J.D. , Park Y.S. , Erickson K. , Butt J. , Bak J.G. , Kim J. , Lee K.D. , Ko J. , Yoon S.W. , Ham C.J. , Kogan L. ,   the MAST Upgrade Team
Published: April 2024

AbstractAbnormal (deviating from the target) variations in the plasma vertical positionZand currentIp(such as vertical displacements, transientIp‘spikes’ and quenches) constitute common elements of a disruption, a phenomenon that is to be mitigated, or ultimately avoided in future reactor-relevant tokamaks. While these abnormalities are generally recognized cross-shot and cross-device, details in terms of appearance (or not) and order of these abnormalities in disruption event chains (DEC) are bound to the plasma state at the time of the chain initiation. Detection of these abnormalities is thus indicative not only of the onset of the plasma collapse itself but also of the disruption driving cause that is promoted at a particular plasma state. Here, the occurrence of disruptions, explored via the detection of anIpquench, and the analysis of DEC constituted byIpandZabnormalities is reported for in total seven full device-year pairs of operation of three machines (4, 2 and 1 years of KSTAR, MAST-U and NSTX-U operation, respectively) using the DECAF code expanded tools and capabilities. It is shown that the disruption occurrence depends not only on the details of the plasma state but also on (device-dependent) technical elements of the shot exit scenario. Year-to-year changes in the main disruption causes and a reduction in the disruptivity rate, bound by device and operation upgrades, are reported. Particular trigger instances of DEC (and the full chains when applicable) are shown to occupy different parts of the operation space diagrams, in accordance with prior expectations. Plasma elongation is identified as an important factor influencing details of the chains and its role will be further explored.
Design of an actuator with bionic claw hook–suction cup hybrid structure for soft robot
Authors: Wang Xingxiang , Lin Aomin , Yuan Wenqing , Hu Hongwei , Cheng Guanggui , Ding Jianning 
Published: April 2024

Abstract
To improve the adaptability of soft robots to the environment and achieve reliable attachment on various surfaces such as smooth and rough, this study draws inspiration from the collaborative attachment strategy of insects, cats, and other biological claw hooks and foot pads, and designs an actuator with a bionic claw hook–suction cup hybrid structure. The rigid biomimetic pop-up claw hook linkage mechanism is combined with a flexible suction cup of a ‘foot pad’ to achieve a synergistic adhesion effect between claw hook locking and suction cup adhesion through the deformation control of a soft pneumatic actuator. A pop-up claw hook linkage mechanism based on the principle of cat claw movement was designed, and the attachment mechanism of the biological claw hooks and footpads was analysed. An artificial muscle-spring-reinforced flexible pneumatic actuator (SRFPA) was developed and a kinematic model of the SRFPA was established and analysed using Abaqus. Finally, a prototype of the hybrid actuator was fabricated. The kinematic and mechanical performances of the SRFPA and entire actuator were characterised, and the attachment performance of the hybrid actuator to smooth and rough surfaces was tested. The results indicate that the proposed biomimetic claw hook–suction cup hybrid structure actuator is effective for various types of surface adhesion, object grasping, and robot walking. This study provides new insights for the design of highly adaptable robots and biomimetic attachment devices.
Simulation and experimental study of notched cantilever beam for improved vibration energy harvesting
Authors: Tamrakar Rohit , Nannaware Pushparaj 
Published: April 2024

Abstract
This research paper addresses the design and analysis of a Notched Cantilever Beam Energy Harvester (NCBEH) aimed at enhancing vibration energy harvesting. The voltage output from Lead Zirconate Titanate (PZT) piezoelectric material is directly related to the strain it experiences. Therefore, numerical simulations using ANSYS were conducted to investigate the variations in natural frequency and stress–strain distribution with respect to slot length in a slotted cantilever beam. Additionally, a notch was introduced into the beam to further enhance strain distribution. The study found that, with precise PZT placement, an NCBEH with a 55 mm slot length can generate 15% more voltage output at lower natural frequencies compared to existing Piezoelectric Cantilever Beam Energy Harvesters (PCEH) [1]. Experimental tests were also conducted to compare the voltage output response of the NCBEH and the PCEH, with the results showing good agreement with the numerical simulation findings.
Private list sharing leads to cooperation and central hubs emergence in ABM
Authors: Vasellini Riccardo , Cecconi Federico , Mocenni Chiara 
Published: April 2024

Abstract
We introduce an agent based model framework to investigate how an alternative to classic image score and gossip can support the emergence of cooperation in a repeated prisoner dilemma game with agents employing mixed strategies. We debate the universality of image scores, arguing that they cannot be considered an objective property of the agents observed but rather a subjective property of each observer. From this assumption, we develop a private list mechanism for opponent selection and gossip sharing among the population of the simulation. The results show that the private list mechanism is able to foster the emergence of cooperation, and that for various levels of list usage different levels of cooperation correspond in the system. Finally, we observe interesting topological properties emerging, with networks characterised by one ‘super-hub’ connected to every other node, suggesting the emergence of centralized entities to support cooperation.
Women’s leadership in climate-resilient agrifood systems: defining a future research agenda
Authors: Morgan Miranda Yeen , Bryan Elizabeth , Elias Marlène 
Published: April 2024

Abstract
Women’s leadership is increasingly considered critical for achieving climate-resilient agrifood systems. Numerous initiatives and policies highlight the business case for women’s leadership to deliver a range of positive social, economic and environmental outcomes. In this Perspective, we examine the business case, finding uneven evidence linking women’s leadership to increased resilience to climate change. We problematize the ways women’s leadership is typically understood in this area and argue that, despite the value and utility of understanding the pathways through which women’s leadership can strengthen climate-resilient agrifood systems, support for increasing women’s leadership should not be contingent on proving the business case or its instrumental value. Rather, increasing the leadership of women in all their diversity in climate action is a moral imperative and non-negotiable due to women’s human right to have meaningful influence in the decisions that affect their lives. Finally, we propose ways to reframe the debate on women’s leadership in climate and agrifood systems and suggest priorities for future research in this area.
Geothermal power generation potential in the United States by 2050
Authors: Chen Chen , Merino-Garcia Daniel , Lines Timothy D G H , Cohan Daniel S 
Published: April 2024

Abstract
Geothermal energy provides a dispatchable source of carbon-free electricity that can balance the output of variable resources. However, geothermal provides just 3.7 gigawatts (GW
e
) (

<

1%) of electricity in the United States today, mostly from hydrothermal resources that are geographically constrained. Enhanced geothermal systems (EGS), which extract heat from deep rock, could be applicable in more locations. However, baseline levels and potential trends in EGS costs have been insufficiently characterized by previous studies. Here, we assess geothermal penetration potential by using as baseline the latest available data on drilling costs from three costing models to create updated estimates of costs and performance. We input those estimates along with various scenarios of cost trends, emissions policies, and electricity demand into the regional energy deployment system (ReEDS) capacity expansion model to simulate electricity generation in the United States through 2050. The scarcity of hydrothermal resources limits deployments to no more than 18 GW
e
across our scenarios. EGS is more costly than hydrothermal for now, but it has greater potential to scale nationwide. Thus, future deployments of EGS depend strongly on projected cost reductions and emissions policies. In scenarios with moderate (

<

50%) reductions in costs by 2050, very little EGS is likely to be built, since wind and solar with storage provide lower-cost electricity. However, over 70% cost reductions from our updated baseline would make geothermal the least-cost carbon-free dispatchable resource. Under those cost trends, we project that 3 GW
e
of EGS would be built by 2050 under existing policies, 11 GW
e
with a 95% decarbonization policy, and 152 GW
e
if full decarbonization of electricity is mandated. Most geothermal would likely first be built in western states with the steepest subsurface temperature gradients, although mandates for full decarbonization could drive it to be deployed in other states.
Even worse for Black girls: the longitudinal association of racial bullying with the initiation of alcohol and tobacco use
Authors: Menezes Alessandra A S , Sanchez Zila M , Demarzo Marcelo , Rezende Leandro F M , Miskolci Richard 
Published: April 2024

Abstract
We used Poisson’s linear regression to examine the association between racial bullying (RB) and the initiation of alcohol and tobacco uses after 9 months. Two cluster-randomized controlled trials were conducted in 2019 with children in grades five (girls: 50.0%; 10 years old: 82.0%; White: 36.8%; Black: 58.7%; others: 4.5%) and seven (girls: 49.5%; 12 years old: 78.1%; White: 33.2%; Black: 60.4%; others: 6.4%) from 30 public schools in the municipality of São Paulo, Brazil. We restricted our analyses to 2 subsets of students in each grade: those who reported no lifetime alcohol use at baseline and those who reported no lifetime baseline tobacco use. At baseline, 16.2% of fifth and 10.7% of seventh graders reported suffering from RB in the 30 days before data collection. After 9 months, 14.9% of fifth graders started using alcohol and 2.5%, tobacco. Among seventh graders, the figures were 31.2% and 7.7%, respectively. RB predicted the initiation of use of alcohol (risk ratio [RR] = 1.36; 95% CI, 1.07-1.70) and tobacco (RR = 1.81; 95% CI, 1.14-2.76) among seventh graders, with race-gender differences, particularly in Black girls (alcohol: RR = 1.45; 95% CI, 1.07-1.93; tobacco: RR = 2.34; 95% CI, 1.31-3.99). School-based programs and policies must explicitly address issues related to racism and gender in alcohol and tobacco prevention strategies.