bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oppression and resistance: An analysis of Muslims' experiences of structural violence
Authors: Saleem Rakhshanda , Morrill Zenobia , Brodt Madeline , Pagan‐Ortiz Marta E. 
Published: May 2021

AbstractDiscrimination and vilification of Muslims in the United States have historical and political roots. This study explores everyday incidents of marginalization and oppression through the framework of structural violence. Structural violence refers to the systemic inequalities embedded within societal structures that create and support these oppressive conditions. In this community‐engaged qualitative study, 10 self‐identified Muslims from the northeastern United States were interviewed to understand their lived experiences of structural violence. Using thematic analysis, seven themes were identified: Racialized and xenophobic Islamophobia; normalized violence against Muslims and fear of safety; exclusion, marginalization, and subjugation through policies; Muslims as spokespersons for Islam; Intersecting marginalized identities and oppression; challenges of navigating Muslim identities; resilience and resistance through faith, activism, and community. This study aims to understand and contextualize the experiences of Muslims within a systemic and geopolitical framework. Another critical objective is to promote a discourse to address how academics and clinicians reproduce and maintain structural violence and to instead engage in socially transformative approaches embedded in the principles of decolonizing and mutually‐liberating cross‐struggle solidarity. These must be cultivated through community‐informed intersectional collaborative strategies for dismantling oppressive structures and promoting agency, resilience, activism, and resistance.
The physiology of fish in acidic waters rich in dissolved organic carbon, with specific reference to the Amazon basin: Ionoregulation, acid–base regulation, ammonia excretion, and metal toxicity
Authors: Morris Carolyn , Val Adalberto L. , Brauner Colin J. , Wood Chris M. 
Published: May 2021

AbstractAlthough blackwaters, named for their rich content of dissolved organic carbon (DOC), are often very poor in ions and very acidic, they support great fish biodiversity. Indeed, about 8% of all freshwater fish species live in the blackwaters of the Rio Negro watershed in the Amazon basin. We review how native fish survive these harsh conditions that would kill most freshwater fish, with a particular focus on the role of DOC, a water quality parameter that has been relatively understudied. DOC, which is functionally defined by its ability to pass through a 0.45‐µm filter, comprises a diverse range of compounds formed by the breakdown of organic matter and is quantified by its carbon component that is approximately 50% by mass. Adaptations of fish to acidic blackwaters include minimal acid–base disturbances associated with a unique, largely unknown, high‐affinity Na+ uptake system that is resistant to inhibition by low pH in members of the Characiformes, and very tight regulation of Na+ efflux at low pH in the Cichliformes. Allochthonous (terrigenous) DOC, which predominates in blackwaters, consists of larger, more highly colored, reactive molecules than autochthonous DOC. The dissociation of protons from allochthonous components such as humic and fulvic acids is largely responsible for the acidity of these blackwaters, yet at the same time, these components may help protect organisms against the damaging effects of low water pH. DOC lowers the transepithelial potential (TEP), mitigates the inhibition of Na+ uptake and ammonia excretion, and protects against the elevation of diffusive Na+ loss in fish exposed to acidic waters. It also reduces the gill binding and toxicity of metals. At least in part, these actions reflect direct biological effects of DOC on the gills that are beneficial to ionoregulation. After chronic exposure to DOC, some of these protective effects persist even in the absence of DOC. Two characteristics of allochthonous DOC, the specific absorbance coefficient at 340 nm (determined optically) and the PBI (determined by titration), are indicative of both the biological effectiveness of DOC and the ability to protect against metal toxicity. Future research needs are highlighted, including a greater mechanistic understanding of the actions of DOCs on gill ionoregulatory function, morphology, TEP, and metal toxicity. These should be investigated in a wider range of native fish Orders that inhabit one of the world's greatest biodiversity hotspots for freshwater fishes.
Thermoregulatory strategies of three reclusive lizards (genus Xantusia) from the Baja California peninsula, Mexico, under current and future microenvironmental temperatures
Authors: Arenas‐Moreno Diego M. , Lara‐Resendiz Rafael A. , Domínguez‐Guerrero Saúl F. , Pérez‐Delgadillo Ana G. , Muñoz‐Nolasco Francisco J. , Galina‐Tessaro Patricia , Méndez‐de la Cruz Fausto R. 
Published: May 2021

AbstractThe thermal quality of the habitat is key for the regulation of body temperature in terrestrial ectotherms and, therefore, permits them to carry out their fundamental biological activities. In thermally heterogeneous environments, ectotherms might follow different behavioral or physiological strategies to maintain their body temperature within biologically adequate boundaries, for which they depend on microhabitat selection. These aspects are, thus, relevant in the context of habitat degradation and land‐use change. In this study, we characterized the thermal ecology of three lizard species (genus Xantusia) that differ in microhabitat use along the Baja California peninsula, Mexico. We made three predictions: (1) the three species will follow different thermoregulatory strategies according to habitat thermal quality; (2) the thermal requirements and tolerances of these species will match the environmental or microenvironmental thermal conditions; and (3) due to their habitat and range restriction, the species studied will be highly vulnerable to climate change. Our results indicate the existence of thermoregulatory mechanisms in Xantusia to face thermal heterogeneity, including behavioral thermoregulation by choosing different microhabitats, shifts in activity periods, and adaptation to particular high thermal quality microhabitats. Furthermore, despite their association to specific microhabitats and specialized physiology, the studied species will not be adversely affected by climate change, as the increased microenvironmental temperatures will lead to a higher habitat thermal quality and lower costs of thermoregulation. However, we do not discard other indirect adverse effects of climate change not considered in this study.
SARS‐CoV‐2 rapid antigen test: Fast‐safe or dangerous? An analysis in the emergency department of an university hospital
Authors: Holzner Carola , Pabst Dirk , Anastasiou Olympia Evdoxia , Dittmer Ulf , Manegold Randi Katrin , Risse Joachim , Fistera David , Kill Clemens , Falk Maximilian 
Published: May 2021

AbstractThe use of Antigen point of care tests (AgPOCT) might be an essential tool to fight the coronavirus disease 2019 (COVID‐19) pandemic. Manufacturer information indicates a specificity of about 95% and there is a growing interest to use these tests area‐wide. Therefore, it is necessary to clarify whether AgPOCT can be used safely for “rule‐in” (detection of positive patients) and for “rule‐out” (valid negative testing). Two thousand three hundred and seventy‐five patients received polymerase chain reaction (PCR) testing and AgPOCT for severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) regardless of symptoms. The positive predictive value of symptomatic and asymptomatic patients was compared with a cut‐off threshold cycle (C
t) value of ≤30 and in total. Five hundrded and fifty‐one patients tested positive for the SARS‐CoV‐2 virus by PCR, of whom 35.2% presented without symptoms. In all patients, regardless of their symptoms or C
t values, a sensitivity of 68.9% and a specificity of 99.6% were calculated for AgPOCT. In patients with C
t values ≤30, a sensitivity of 80.5% (95% confidence interval: ±1.62) and a specificity of 99.6% were shown for all tests (symptomatic/asymptomatic). Highly infectious patients (C
t ≤ 20), regardless of symptoms, were reliably detected by the AgPOCT. In infectious patients with C
t values ≤30, the test has a sensitivity of about 80% regardless of COVID‐19 typical symptoms, which is apparently less than the 96.52% specificity indicated by the manufacturer. Relevant improvement in test sensitivity by querying the patients who are symptomatic and asymptomatic is also not feasible. We strongly suggest that we critically question the use of AgPOCT for “rule‐out,” as they only provide a supposed safety.
Artificial intelligence methods applied to financial assets price forecasting in trading contexts with low (intraday) and very low (high‐frequency) time frames
Authors: Petrelli Donata , Cesarini Fabrizio 
Published: May 2021

AbstractFinancial price fast forecasting for high‐frequency algorithmic trading can be improved profitably by using simplified artificial intelligence models. There are several different methodologies for working in algorithmic trading, each specific to the context. The method proposed here is designed to prioritize better performance. The methodology uses a combination of different artificial intelligence techniques, some of which have been revised and simplified to maximize performance. The forecasting part is assigned to a formula based on the Petrelli‐Cesarini (2018) index, specifically designed to speed up the calculation, allowing its use in operating environments with low time frames and high‐frequency trading.
Fabrication and characterization of dextran/zein hybrid electrospun fibers with tailored properties for controlled release of curcumin
Authors: Luo Shiyuan , Saadi Abdullah , Fu Kai , Taxipalati Maierhaba , Deng Lingli 
Published: May 2021

AbstractBACKGROUNDIn recent years, there has been considerable interest in the use of biopolymer electrospun nanofibers for various food applications due to the biocompatibility, biodegradability, and high loading capacity. Herein, we fabricated and characterized novel hybrid electrospun fibers from dextran (50%, w/v) and zein (0–30%, w/v) solutions, and the effects of various zein concentrations on the properties of the hybrid electrospun fibers were investigated.RESULTSWhen zein was added at low concentrations (5% and 10%), dextran and zein showed poor miscibility, as reflected by significantly decreased viscosity of the solutions, and the poor mechanical properties of the derived fiber membranes. When zein was added at medium concentrations (15–25%), hydrogen bonds were formed between dextran and zein molecules, as indicated by the red shift of Fourier‐transform infrared bands and β‐sheet to α‐helix structural transformations. The fiber membranes electrospun from a solution with 25% zein showed the most hydrophobic surface, with a water contact angle of 116.9°. The homogenous dispersion of dextran and zein resulted in improved mechanical properties for fibers electrospun from a solution with 30% zein. Curcumin encapsulating dextran/zein electrospun fibers exhibited effective radical scavenging activity and ferric reducing power, along with the desired controlled release behavior for curcumin delivery.CONCLUSIONFood grade dextran/zein hybrid electrospun fibers demonstrated tunable properties, and appear to be promising as delivery systems for bioactive and edible antimicrobial food packaging. © 2021 Society of Chemical Industry.
Doubly‐Resonant Enhancement of Second Harmonic Generation from a WS2 Nanomesh Polymorph with a Modified Energy Landscape
Authors: Murphy Alexander W. A. , Liu Zichen , Gorbach Andrey V. , Ilie Adelina , Valev Ventsislav K. 
Published: May 2021

AbstractAlthough transition metal dichalcogenides (TMDs, e.g., WS2, WSe2, MoS2, MoSe2) have emerged as highly promising 2D materials for nonlinear optics, they are limited by intrinsically small light‐matter interaction length and (typically) flat‐lying geometries. The first hyperspectral multiphoton analysis of a tridimensional webbed network of densely‐packed stacks (of 1–5 layers) of twisted and/or fused 2D nanosheets of WS2, referred to as “nanomesh”, is presented here. The optical second harmonic generation (SHG) is mapped across the three characteristic spectral features (A, B, and C) and two‐photon luminescence and third harmonic generation signatures are established. Compared to flat‐lying WS2 layers, the nanomesh is highly efficient, broadband, and robust against degradation (with main enhancement originating from the C feature, spreading from 850 to 1100 nm), and scalable in terms of growth. The origin of these spectral differences is assigned to hotspots, whose location changes depending on the wavelength of illumination. The main SHG enhancements result from double resonances in an energy landscape modified by in‐built defects (e.g., vacancies and their passivated variants, or grain boundaries) that induce intra‐bandgap energy levels. These characteristics establish the nanomesh as a prime candidate for integration into quantum optical technologies, such as miniaturized devices on chip.
A novel grid regression demodulation method for radiographic grid artifact correction
Authors: Yu Yongjian , Wang Jue 
Published: May 2021

PurposeIn x‐ray radiography, the commonly used antiscatter grid for enhancing image quality causes artifacts in the form of periodic noises, such as shadows, cutoff, and Moiré fringes. Software degridding is traditionally performed via linear or homomorphic filtering in the spectral domain. These methods inevitably result in image blurring, information loss, and distortion, thus hindering detection and assessment of diseases. We seek effective and practical solutions for grid artifact correction based on spatial‐domain analysis toward high‐quality imaging.MethodsBy analyzing the physical process of grid artifact formation, we track down the root of the problem associated with spectral filtering. We propose the grid regression demodulation (GRD). The degridding cost is forged as a functional of the latent x‐ray photon image and parametric grid model characterizing grid transmission property. Regularization on the grid spectra is incorporated. We devise optimization algorithms for artifact correction and grid pattern estimation. GRD decouples the partially overlapped spectra of the grid and anatomy, and removes the artifacts independently, thus restoring the underlying clinically relevant data.ResultsMethod efficacy is demonstrated using simulated and real data. GRD effectively preserves image edges, textures, and patterns while removing grid artifacts. For the known ground truth setting, GRD gives a near‐perfect correction. For real data, GRD is capable of correcting not only the primary grid artifacts, but also the higher grid harmonic artifacts while keeping image content unaltered, which is unachievable by the other methods. Our method has low residual errors and exhibits a successful demodulation effect without introducing additional artifacts, while ringing or cilia artifacts are present in the others.ConclusionsThe proposed method outperforms the prevalent transform techniques for correcting grid artifacts in digital radiography. It is self‐sustained and self‐adaptive to a range of targets and beam quality. Our approach is advantageous in restoring the latent image while suppressing grid noises. It retrieves the true scale factor of the degridded data, which is unattainable via any spectral filtering techniques. This work unlocks a promising venue to improve and upgrade low‐dose medical radiographic imaging technology.
Influence of polypyrrole nanospheres on the direct current dielectric properties of LDPE
Authors: Zhang Chengcheng , Ren Qiang , Cheng Dahu , Li Chunyang , Yang Jiaming , Zhao Hong 
Published: May 2021

AbstractTo study the effect of nano conducting materials on the direct current (DC) dielectric properties of low density polyethylene (LDPE), polypyrrole nanospheres are prepared by the soft template method and then melt‐blended with LDPE to obtain LDPE/polypyrrole nanocomposites. The micro‐structure, space charge distribution, thermally stimulated depolarization current, DC conductivity and DC breakdown strength of the nanocomposites are investigated. The results show there is interaction between polypyrrole nanospheres and LDPE, which will not affect the crystal structure of LDPE, but slightly increase the crystallinity of LDPE/polypyrrole nanocomposites. Polypyrrole nanospheres can introduce deep traps in LDPE to capture space charge carriers, which will suppress the accumulation of space charges in LDPE and reduce the DC conductivity. The DC breakdown strength of LDPE/polypyrrole nanocomposites is improved slightly by adding a small amount of polypyrrole nanospheres.
General dental practitioners’ knowledge and attitudes on children’s pain and pain management—A questionnaire survey
Authors: Krekmanova Larisa , Nilsson Stefan , Hakeberg Magnus , Klingberg Gunilla , Robertson Agneta 
Published: May 2021

AbstractThe aim was to study general dental practitioners’ knowledge and attitudes on pain and pain management in children and adolescents, using a multidimensional questionnaire. There is little information on dentists’ views on pain in children. The research question was how attitudes and knowledge may correlate to the dentists’ age, sex, years of professional experience, the proportion of working time devoted to treating children and adolescents, as well as being a parent. At the time of the study, 387 general dentists working for the Public Dental Service participated in a web‐based, multidimensional validated questionnaire holding the categories (A) views on the care of children in pain, (B) physiology, (C) pain alleviation, (D) medication, (E) sociology/psychology, (F) Pain assessment instruments and methods, (G) non‐medication methods of pain alleviation, and (H) documentation of pain management. The age categories were given as; below 25, 25‐35, 36‐45, 46‐55 years, and older than 55 years of age. 71% of the responders were female. The dentists’ age cohort, as well as the years of professional experience, tended to make a difference as to the pain interventions in children and adolescents (P < 0.03). The female dentists, in comparison to the male dentists, conveyed different pain treatment strategies (P < 0.03). The proportion of working time devoted to treating children and adolescents, as well as being a parent, did not show significant differences regarding pain strategies. Associations were observed between the age of the dentists studied, the number of years as professionals and the knowledge and attitudes that benefit children's pain treatment. Being a parent was not significant. In this studied group, female dentists displayed significantly more care regarding pain management, than did their male colleagues. Furthermore, the study highlighted the need for a short questionnaire, user‐friendly yet with retained multidimensionality.
Markov chain to analyze web usability of a university website using eye tracking data
Authors: Zammarchi Gianpaolo , Frigau Luca , Mola Francesco 
Published: May 2021

AbstractWeb usability is a crucial feature of a website, allowing users to easily find information in a short time. Eye tracking data registered during the execution of tasks allow to measure web usability in a more objective way compared to questionnaires. In this work, we evaluated the web usability of the website of the University of Cagliari through the analysis of eye tracking data with qualitative and quantitative methods. Performances of two groups of students (i.e., high school and university students) across 10 different tasks were compared in terms of time to completion, number of fixations and difficulty ratio. Transitions between different areas of interest (AOI) were analyzed in the two groups using Markov chain. For the majority of tasks, we did not observe significant differences in the performances of the two groups, suggesting that the information needed to complete the tasks could easily be retrieved by students with little previous experience in using the website. For a specific task, high school students showed a worse performance based on the number of fixations and a different Markov chain stationary distribution compared to university students. These results allowed to highlight elements of the pages that can be modified to improve web usability.
Detection and Removal of Arsenite from Water Using Bis‐Urea Supramolecular Polymer and Dipeptide Adsorbent
Authors: Nandi Sujay Kumar , Kumar Santosh , Chowdhury Srayoshi Roy , Ibukun Ibukun‐Olamilekan Joseph , Haldar Debasish 
Published: May 2021

AbstractArsenic is one of the most toxic element and contaminant of groundwater. Arsenic enters into the groundwater from natural deposits through various industrial and agricultural activities. Though arsenic can present in different oxidation states starting from−3 to +5, the trivalent As(III) (arsenite) is most toxic. A cost‐effective, easy‐to‐use in‐field arsenite sensor in aqueous media has been developed. The (6‐ureido‐pyridine‐2‐yl)‐urea has been synthesized via simple one‐pot synthesis by treating 2,6‐diaminopyridine with potassium cyanate at 80 °C. The bis‐urea can selectively sense arsenite and form a light yellow color supramolecular polymer in aqueous media even in the presence of other biologically and environmentally important ions. Various analytical techniques were employed to study the arsenite sensing, and the detection limit was found to be 73.6 nM. The immediate, accurate, selective, naked‐eye detection of arsenite makes it suitable for in‐field water testing. We have also developed a device packed with dipeptide and silica that can remove 71.1 % arsenite‐ supramolecular polymer in a single touch in 5 minutes. Notably, the filter can be used upto five cycles efficiently. The results demonstrate the potential of the bis‐urea supramolecular polymer and dipeptide adsorbent for the efficient and sustainable remediation of arsenite contamination.
Unstable and Stable Thermal Hysteresis Under Thermal Triangle Waves
Authors: Arisawa Mieko , Iwamoto Rina , Yamaguchi Masahiko 
Published: May 2021

AbstractA 1 : 1 mixture of aminomethylenehelicene (P)‐tetramer with C16 alkyl groups (P)‐1‐C16 and (M)‐pentamer (M)‐2 in fluorobenzene forms hetero‐double‐helices, and the processes of formation and dissociation exhibit thermal hysteresis on cooling and heating. When thermal triangle waves with repeated cooling and heating cycles are applied, unstable thermal hysteresis appears, which becomes a stable thermal hysteresis after sufficient numbers of cycles. The phenomenon of middle‐range stable thermal hysteresis is observed in this case. Properties of unstable and stable thermal hysteresis are examined under various thermal triangle waves.