bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fuzzy clustering with $$\hbox {L}_0$$ regularization
Authors: Ferraro Maria Brigida , Forti Marco , Giordani Paolo 
Published: February 2025

Abstract
The Fuzzy K-Means algorithm extends the well-known classical K-Means algorithm by replacing the standard allocation matrix with the membership degree one. Consistently with the fuzzy approach to clustering, this allows for obtaining a soft assignment of the units to the clusters. The units are assigned to the clusters with membership degree taking values in the unit interval. In practice, what we get from Fuzzy K-Means is a fuzzy partition where even the units clearly belonging to only one cluster generally present non-zero membership degrees to all the clusters. In order to overcome this drawback, a generalization of Fuzzy K-Means is proposed where an

$$\hbox {L}_0$$

L
0

regularization term for the membership degree matrix is introduced. This makes it possible to obtain a sparse membership degree matrix, where the units that clearly belong to one cluster have membership degrees strictly equal to one to the cluster involved and zero to the other clusters, without compromising the soft membership degrees of the units with unclear assignments. The adequacy of the proposal is evaluated by means of simulation and real-case studies.
Alcohol use in Early Midlife: Findings from the Age 37 Follow-Up Assessment of the FinnTwin12 Cohort
Authors: Cooke Megan E. , Lumpe Erin , Stephenson Mallory , Urjansson Mia , Aliev Fazil , Palviainen Teemu , Brislin Sarah J. , Piirtola Maarit , Rabinowitz Jill , Latvala Antti , Barr Peter B. , Vuoksimaa Eero , Maes Hermine H. M. , Viken Richard , Rose Richard J. , Kaprio Jaakko , Dick Danielle M. , Aaltonen Sari , Salvatore Jessica E. 
Published: February 2025

Abstract
This paper provides an overview of the most recent assessment, collected in early midlife, of the FinnTwin12 cohort, a population-based study of Finnish twins born in 1983–1987. The twins were invited to complete an online survey assessing a range of variables, including physical and mental health, alcohol use and problems, other substance use, and early midlife environments (e.g., parenthood). In total, 2,085 individuals (~ 40% of the original sample) completed the survey (551 complete twin pairs, 58.7% female, 37.3% monozygotic, Mage = 37.2 years, SD = 1.47 years, age range = 34–39 years). Individuals who participated were more likely to be female, monozygotic, and have higher parental education and less hyperactivity/impulsivity and aggression at age 12 when compared to individuals who were invited but did not participate. Parental alcohol misuse and the twins’ alcohol use and misuse at age 14 were not related to study retention. Alcohol misuse in early midlife was positively associated with nicotine dependence, lifetime use of cannabis and other drugs, trauma exposure, and depressive symptoms, and negatively associated with physical health and having biological children. These new data expand upon the wealth of measures collected as part of previous assessments, expanding the scope of work on the etiology and correlates of alcohol misuse within a longitudinal, genetically-informed framework. In addition to these new survey measures, we are planning an in-person assessment to collect physiological measurements and conduct additional in-depth phenotyping on a subset of twins who have been more intensively studied over the years.
Exploiting effective negative curvature directions via SYMMBK algorithm, in Newton–Krylov methods
Authors: Fasano Giovanni , Piermarini Christian , Roma Massimo 
Published: February 2025

Abstract
In this paper we consider the issue of computing negative curvature directions, for nonconvex functions, within Newton–Krylov methods for large scale unconstrained optimization. In the last decades this issue has been widely investigated in the literature, and different approaches have been proposed. We focus on the well known SYMMBK method introduced for solving large scale symmetric possibly indefinite linear systems (Bunch and Kaufman in Math Comput 31:163–179, 2003; Chandra in Conjugate gradient methods for partial differential equations, Yale University, New Haven, 1978; Conn et al. Trust-region methods. MPS-SIAM Series on Optimization, Philadelphia, 2000; HSL 2013: A collection of Fortran codes for large scale scientific computation. http://www.hsl.rl.ac.uk/), and show how to exploit it to yield an effective negative curvature direction in optimization frameworks. The distinguishing feature of our proposal is that the computation of negative curvatures is basically carried out as by–product of SYMMBK procedure, without storing no more than two additional vectors. Hence, no explicit matrix factorization or matrix storage is required. An extensive numerical experimentation has been performed on problems; the obtained results have been analyzed also through novel profiles (Quality Profiles) which highlighted the good capability of the algorithms which use negative curvature directions to determine better local minimizers.
Seasonal variations, source apportionment, and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in sediments from Klip River, Johannesburg, South Africa
Authors: Makobe Samuel , Seopela Mathapelo P. , Ambushe Abayneh A. 
Published: February 2025

Abstract
The widespread occurrence of polycyclic aromatic hydrocarbons (PAHs) in water bodies is a significant cause of concern due to their persistence and toxicity. This study aimed at assessing the qualitative and quantitative profile of 16 EPA PAHs present in sediment collected from nine sites along the Klip River, Johannesburg, South Africa. The target compounds were extracted from sediment by microwave-assisted extraction (MAE). The extraction method accuracy was evaluated by analyzing certified reference material of sediment (CRM-104). The total concentration of PAHs detected in sediment samples ranged from 1.46 to 7.41 mg/kg. High molecular weight (HMW) PAHs were found to be in higher concentrations for both low flow (24.5 mg/kg) and high flow (19.4 mg/kg) seasons compared to the lower molecular weight (LMW) PAHs, which had 11.1 mg/kg for low flow and 5.63 mg/kg for high flow seasons. For identification of source of PAHs in sediments, the diagnostic ratio was employed, which revealed the PAHs were from petrogenic and pyrogenic sources. Toxicity test using zebrafish embryo development test (ZFET) resulted in high mortality, low hatch rate, and high malformations, which indicated the contamination of sediments from the Klip River. These findings suggest that exposure to this water system poses risks to the environment, aquatic life, and humans who depend on it.
The Unbearable Indefiniteness of Spacetime
Authors: Cinti Enrico , Mariani Cristian , Sanchioni Marco 
Published: February 2025

Abstract
We consider the observables describing spatiotemporal properties in the context of two of the most popular approaches to quantum gravity (QG), namely String Theory and Loop QG. In both approaches these observables are described by non-commuting operators. In analogy with recent arguments put forward in the context of non-relativistic quantum mechanics [see Calosi and Mariani (Philos. Compass 16(4):e12731, 2021) for a review], we suggest that the physical quantities corresponding to those observables may be interpreted as ontologically indeterminate—i.e., indeterminate in a way that is non-epistemic and semantic-independent. This working hypothesis has not received enough attention in the current debate on QG, and yet it may prove explanatory useful in several respects. First, it provides a clear background for understanding how some features of QG are ontologically continuous to features of quantum mechanics. Second, it sets the stage for asking new interesting questions about QG, for instance concerning the status of the so-called Eigenstate-Eigenvalue link. Third, it indirectly shows how the debate on ontological indeterminacy may extend well beyond the non-relativistic case, contrary to what seems to be assumed. Fourth, and perhaps more importantly, it provides a promising alternative to the received view on QG [Wüthrich et al. (Philosophy Beyond Spacetime: Implications from Quantum Gravity, Oxford University Press, Oxford, 2021)] according to which spacetime is not fundamental. On the view we shall suggest, spacetime may be indeterminate and yet fundamental.
MOF and MOF-based membranes: promising solutions for pharmaceutical wastewater treatment
Authors: Islam Izaz Ul , Hu Xudong , Shang Jingyi , Ashraf Muhammad Ayaz , Ali Tariq , Aslam Awais Ali , Li Shuang , Li Deliang , Nazir Muhammad Shahid , Wang Xinhai , Yabalak Erdal 
Published: February 2025

Abstract
Water contamination has become a significant global issue in recent decades, with pollutants, such as heavy metals, acids, organic solvents, and pharmaceutical waste contributing to environmental degradation. Various techniques are employed for treating pharmaceutical wastewater, but metal–organic frameworks (MOFs) are gaining increasing attention due to their unique properties. MOFs offer exceptional porosity, modular structures, high crystallinity, customizable chemical components, large specific surface area, simple functionalization, and numerous active sites. These coordination compounds consist of poly-nuclear metal nodes and organic linkers, forming highly porous structures. This review focuses on MOF-based membrane separation techniques, including membrane filtration (MF), nanofiltration, organic solvent nanofiltration, ultrafiltration (UF), microfiltration, forward osmosis, reverse osmosis, membrane pervaporation, and membrane distillation, along with their mechanisms for removing pharmaceutical waste. MOFs have shown great promise in enhancing membrane performance by improving adsorption capacities, increasing water flow rates, and optimizing membrane properties. Integrating MOFs with materials like graphene oxide, titania, and silica has further improved their performance. Additionally, green synthesis methods are being developed to create eco-friendly MOFs for sustainable wastewater treatment. MOFs demonstrate effective adsorption capacities for various contaminants, including antibiotics, such as tetracycline, nitroimidazole, and quinolone. Functionalizing MOFs with specific groups has been shown to further enhance their adsorption efficiency. Overall, MOFs offer significant potential for advancing pharmaceutical wastewater treatment and addressing global water contamination challenges.
The Optical Properties, UV-Vis. Absorption and Fluorescence Spectra of 4-Pentylphenyl 4-n-benzoate Derivatives in Different Solvents
Authors: Sıdır Yadigar Gülseven , Sıdır İsa 
Published: February 2025

Abstract
In this paper, electronic absorbance and fluorescence spectra of 4-Pentylphenyl 4-n-benzoate derivatives have been measured in 29 solvents, which are non-polar, polar protic and polar aprotic solvents, and electronic transitions that vary depending on the solvent are identified. As the solvent polarity increases, the forbidden energy difference between the frontier orbitals decreases. The statistical models in order to describe the solvent effect were derived using different solvent parameters. Quite complex and multiple absorbance transitions were observed in different solvent environments. Local fluorescence transition and intramolecular charge transfer occurred in the fluorescence spectra. Absorbance transitions are global transitions, and π*←π is the absorbance electronic transition. The frontier molecular orbitals and electrostatic potential surface were founded using quantum chemical calculations. Refractive indices were found with five different methods and forbidden energy gaps were found with the Tauc method. The forbidden energy ranges were found around 4.1 and 4.5, and the forbidden energy gap decreased as the alkyl chain became longer. All compounds can be defined as insulation materials according to the forbidden energy range. Refractive index values close to the E7 liquid crystal mixture used in liquid crystal display panels were found in the investigated liquid crystals.
Nudging Hospital Visitors Towards Stair Use, in Greece
Authors: Tzikas Alexandros , Koulierakis George , Athanasakis Konstantinos , Merakou Kyriakoula 
Published: February 2025

Abstract
Stair use is a physical activity that can be easily incorporated into daily routines, offering numerous health benefits. Nudges are increasingly adopted in public health interventions to promote healthy behaviours, such as physical activity. This study aimed to investigate the effectiveness of nudge-based posters in increasing stair use among hospital visitors in Athens, Greece. The posters were placed at the point-of-choice between stairs and elevators. Hospital visitors using either the stairs or elevators were observed across five phases, namely, baseline, two intervention phases, and two post-intervention phases, each lasting four days. A total of 3,071 choices between the stairs and the elevator were recorded during the study. The differences in proportions of stair users between stages was assessed using the Chi-square test. The results showed that the posters significantly increased stair use from 22.6% at baseline to 37.3% during the first intervention phase. Stair use dropped back to 22.2% during the first post-intervention phase. During the second intervention, stair use rising to 37.8%, followed by a decrease to 22.8% in the second post-intervention phase. These findings suggest that posters placed at the point-of-choice can effectively promote immediate behavioural changes, increasing stair use among hospital visitors. However, their long-term effect has yet to be verified. The simplicity, low cost, and easy applicability of posters make them a promising nudge-based intervention within hospital settings. These characteristics also support the generalization of this approach to other environments as part of public health policies aimed at promoting physical activity and improving overall population health.
Applications of unoccupied aerial systems (UAS) in landscape ecology: a review of recent research, challenges and emerging opportunities
Authors: Villarreal Miguel L. , Bishop Tara B. B. , Sankey Temuulen Ts. , Smith William K. , Burgess Matthew A. , Caughlin T. Trevor , Gillan Jeffrey K. , Havrilla Caroline A. , Huang Tao , LeBeau Raymond L. , Norton Cynthia Libantino , Sankey Joel B. , Scholl Victoria M. , von Nonn Joshua , Yao Erika H. 
Published: February 2025

Abstract

Context
Unoccupied aerial systems/vehicles (UAS/UAV, a.k.a. drones) have become an increasingly popular tool for ecological research. But much of the recent research is concerned with developing mapping and detection approaches, with few studies attempting to link UAS data to ecosystem processes and function. Landscape ecologists have long used high resolution imagery and spatial analyses to address ecological questions and are therefore uniquely positioned to advance UAS research for ecological applications.

Objectives
The review objectives are to: (1) provide background on how UAS are used in landscape ecological studies, (2) identify major advancements and research gaps, and (3) discuss ways to better facilitate the use of UAS in landscape ecology research.

Methods
We conducted a systematic review based on PRISMA guidelines using key search terms that are unique to landscape ecology research. We reviewed only papers that applied UAS data to investigate questions about ecological patterns, processes, or function.

Results
We summarize metadata from 161 papers that fit our review criteria. We highlight and discuss major research themes and applications, sensors and data collection techniques, image processing, feature extraction and spatial analysis, image fusion and satellite scaling, and open data and software.

Conclusion
We observed a diversity of UAS methods, applications, and creative spatial modeling and analysis approaches. Key aspects of UAS research in landscape ecology include modeling wildlife micro-habitats, scaling of ecosystem functions, landscape and geomorphic change detection, integrating UAS with historical aerial and satellite imagery, and novel applications of spatial statistics.
Cauchy–Schwarz-type inequalities for solutions of Levi-Civita-type functional equations
Authors: Páles Zsolt , Shihab Mahmood Kamil 
Published: February 2025

Abstract
The main goal of this paper is to show that if a real-valued function defined on a groupoid satisfies a certain Levi-Civita-type functional equation, then it also fulfills a Cauchy–Schwarz-type functional inequality. In particular, if the groupoid is the multiplicative structure of a commutative ring, then we can establish the existence of nontrivial additive functions satisfying inequalities connected to the multiplicative structure.
Nonlinear wave propagation in a two-dimensional lattice model of textile metamaterials
Authors: Arena Andrea , Lepidi Marco 
Published: February 2025

Abstract
An original parametric lattice model is formulated to describe the propagation of harmonic elastic waves in two-dimensional textile metamaterials. Within a weak nonlinear regime, the free undamped motion of the textile metamaterial, starting from a spatially periodic pretensioned configuration, is governed by nonlinear differential difference equations. Quadratic and cubic nonlinearities arise from the elastic contact between plain woven yarns. By applying the asymptotic method of multiple scales, the nonlinear dynamics of the periodic cell are governed by an ordered hierarchy of linear perturbation equations. Therefore, by virtue of the linearity and spatial periodicity, the Floquet-Bloch theory is recursively applied at each order of the perturbation equations to study the linear and nonlinear dispersion properties. Specifically, the lowest order solutions return the linear dispersion diagram characterizing the free undamped propagation of small-amplitude harmonic waves. Within the technical range of the parameters, the dispersion diagram shows the coexistence of two passbands, separated by a large mid-frequency stopband. By virtue of an energy-based classification criterion, the different polarizations of the waves propagating in the low-frequency and high-frequency bands are disclosed. The higher orders allow to determine analytically the combined effects of the nonlinearities on the dispersion properties, in the absence of internal resonances. In particular, the wavefrequencies exhibit a quadratic dependence on the wave oscillation amplitude, characterized by a systematic softening behavior. Moreover, the amplitudes of the damped nonlinear response induced by the external excitation due to a harmonically oscillating pretension are analyzed in the frequency domain and the instability regions of the primary resonance are obtained in the whole range of feasible mechanical parameters. Finally, analytical results are successfully validated by numerical simulations in the time domain.
Machine learning models for segmentation and classification of cyanobacterial cells
Authors: Huffine Clair A. , Maas Zachary L. , Avramov Anton , Brininger Christian M. , Cameron Jeffrey C. , Tay Jian Wei 
Published: February 2025

Abstract
Timelapse microscopy has recently been employed to study the metabolism and physiology of cyanobacteria at the single-cell level. However, the identification of individual cells in brightfield images remains a significant challenge. Traditional intensity-based segmentation algorithms perform poorly when identifying individual cells in dense colonies due to a lack of contrast between neighboring cells. Here, we describe a newly developed software package called Cypose which uses machine learning (ML) models to solve two specific tasks: segmentation of individual cyanobacterial cells, and classification of cellular phenotypes. The segmentation models are based on the Cellpose framework, while classification is performed using a convolutional neural network named Cyclass. To our knowledge, these are the first developed ML-based models for cyanobacteria segmentation and classification. When compared to other methods, our segmentation models showed improved performance and were able to segment cells with varied morphological phenotypes, as well as differentiate between live and lysed cells. We also found that our models were robust to imaging artifacts, such as dust and cell debris. Additionally, the classification model was able to identify different cellular phenotypes using only images as input. Together, these models improve cell segmentation accuracy and enable high-throughput analysis of dense cyanobacterial colonies and filamentous cyanobacteria.
Corruption: A situational action view
Authors: Uhl Andrzej , Herrmann Christoph , Treiber Kyle H. 
Published: February 2025

Abstract
This article presents an integrative, analytic, and interactive approach to explaining corruption. We find that extant research, while empirically rich, often lacks grounding on the micro level of analysis, operates on unspecified or implausible decision-making models, does not clearly distinguish between proximal and distal causes, and does not attempt to study the interactions between individual propensities and corruption-conducive settings (situational analysis). The theoretical traditions of rational choice and culture provide insight into some but not all corrupt acts, and are limited in the extent to which they explain why and how an individual chooses to act corruptly. Drawing on analytic criminology, we propose situational action theory (SAT) as an alternative explanation of corruption as moral action that forefronts rule guidance, conditional relevance of controls, and the interplay of people and settings. This conceptual framework will allow researchers to build on existing empirical work while distinguishing causes of corruption from its mere correlates. The article concludes with some reflections on bridging the gap between situational theory and empirical research into corruption.
Understory vegetation can promote bird sounds and reduce traffic noise in urban park soundscapes
Authors: Uebel Konrad , Bonn Aletta , Marselle Melissa , Dean Angela J. , Rhodes Jonathan R. 
Published: February 2025

Abstract
Natural soundscapes commonly experienced in parks are increasingly valued as an important cultural ecosystem service with the potential to promote greater mental well-being for people. Yet the quality of urban park soundscapes can differ, containing varying proportions of natural sounds, such as bird calls, and anthropogenic noise, such as vehicle traffic. These soundscapes are linked to underlying landscape features yet their role in shaping both beneficial natural sounds and unwanted anthropogenic noise remains unclear. We address this gap by analysing the influence of park and surrounding landscape characteristics on a range of urban park soundscapes in Brisbane, Australia, with respect to bird sounds and traffic noise. We recorded audio in 67 parks in Brisbane, Australia and quantified bird call volume, bird call diversity and traffic noise volume for each recording. We then used multiple linear regression analyses to determine the influence of land cover classes, vertical vegetation density and distance to a main road on each of these dimensions. We show that greater vegetation density in the understory has a positive influence on the loudness and diversity of bird calls within park soundscapes and a negative influence on traffic noise. Traffic noise was also associated with greater proximity to a main road and higher canopy height, whilst greater impervious surface appeared to increase the dominant sound type (i.e. either bird sounds or traffic noise) within the soundscape. These findings highlight the importance of managing the landscape features of urban parks to promote higher quality soundscapes. Results suggest that greater vegetation density and complexity, particularly in the understory, has potential as a nature-based solution to enhance the diversity of bird calls within park soundscapes whilst also mitigating traffic noise.