bluuebunny/crossref_metadata_2025_split huggingface dataset:
Combining prospective and retrospective motion correction based on a model for fast continuous motion
Authors: Hucker Patrick , Dacko Michael , Zaitsev Maxim 
Published: April 2021

PurposeProspective motion correction (PMC) and retrospective motion correction (RMC) have different advantages and limitations. The present work aims to combine the advantages of both for rigid body motion, aiming at correcting for faster motions than was previously achievable. Additionally, it provides insights into the effects of motion on pulse sequences and MR signals with a goal of further improving motion correction in the future.MethodsThe effective encoding trajectory and a global phase offset in a moving object are calculated based on complete gradient waveforms of an arbitrary sequence and a continuous motion model. These data are used to feed the forward signal model, which is then used in iterative image reconstruction to suppress the artifacts still present after the PMC.ResultsVerification experiments with a rotation phantom and in vivo were performed. Predictions of simulated motion artifacts for PMC based on sequence waveforms are very accurate. The performance at combined PMC+RMC is limited by Nyquist violations in the sampled k‐space and can be compensated by oversampling.ConclusionThe combined correction results in better images than pure PMC in the presence of fast motion. The predictions of artifacts are very accurate, allowing for comparing sequences or protocols in simulations. The observed artifacts due to Nyquist violations are expected to be corrected by utilizing parallel imaging.
Stress evolution in elastically heterogeneous and non‐linear fluid‐saturated media with a Green's function approach
Authors: Peres Matheus L. , Mesquita Leonardo C. , Leroy Yves M. , Sotelino Elisa D. 
Published: April 2021

AbstractClassical analytical solutions of linear elasticity are used as auxiliary solutions to solve non‐linear, and elastically heterogeneous problems on fluid‐saturated media. The 2D Kelvin's solution for a homogeneous space is considered here for simplicity sake. The material non‐linearity could be due to irreversible deformations or non‐linear elasticity response typical of 4D analysis as it is done here. The general procedure relies on a discrete collocation method and a fixed point iterative approach to construct the displacement field. The method is validated by comparing the numerical results with the analytical solution for a layered cylinder embedded in an infinite space. The h‐convergence is checked numerically illustrating the strong influence of the number of facets used to discretize the boundaries. The convergence of the iterative process based on the displacement norm is of a quasi‐quadratic rate for near homogeneous materials and declines to sub‐linear rates as the contrast in elasticity modulus exceeds 15% of the values considered for the Green's function. The method is then applied to a 2D tilted block region where the depleting reservoir has elasticity parameters function of the volumetric strain, to shed some light on the 4D effects. It is shown that the velocity changes are sensitive to the volumetric strain as well as to the strain in the wave propagating direction. Differences, including the anisotropy due to the structural response at the field scale, between the predictions based on this non‐linear isotropic elasticity and the classical R‐factor approach are finally discussed.
A Novel Graphene Quantum Dot‐Based mRNA Delivery Platform
Authors: Liu Ya , Zhao Changhong , Sabirsh Alan , Ye Lilei , Wu Xiaoqiu , Lu Hongbin , Liu Johan 
Published: April 2021

AbstractAbstract: During the last decades, there has been growing interest in using therapeutic messager RNA (mRNA) together with drug delivery systems. Naked, unformulated mRNA is, however, unable to cross the cell membrane and is susceptible to degradation. Here we use graphene quantum dots (GQDs) functionalized with polyethyleneimine (PEI) as a novel mRNA delivery system. Our results show that these modified GQDs can be used to deliver intact and functional mRNA to Huh‐7 hepatocarcinoma cells at low doses and, that the GQDs are not toxic, although cellular toxicity is a problem for these first‐generation modified particles. Functionalized GQDs represent a potentially interesting delivery system that is easy to manufacture, stable and effective.
Metal Binding Ability of Small Peptides Containing Cysteine Residues
Authors: Lukács Márton , Csilla Pálinkás Dóra , Szunyog Györgyi , Várnagy Katalin 
Published: April 2021

AbstractThe Cd(II)‐, Pb(II)‐, Ni(II)‐ and Zn(II)‐complexes of small terminally protected peptides containing CXXX, XXXC, XCCX, CXnC (n=1–3) sequences have been studied with potentiometric, UV/Vis and CD spectroscopic techniques. The cysteine thiolate group is the primary binding site for all studied metal ions, but the presence of a histidyl or aspartyl side chain in the molecule contributes to the stability of the complexes. For two‐cysteine containing peptides the (S−,S−) coordinated species are formed in the physiological pH range and the stability increases in the Ni(II)<Zn(II)<Pb(II)<Cd(II) order. As a conclusion, the inserting of −CXXC− sequence into the peptide makes the synthesis of peptides with high selectivity to toxic Cd(II) or Pb(II) ion possible. In addition, the spectroscopic characterization of these complexes can contribute to the discovery of the exact binding site and binding mode of longer peptides mimicking the biologically important proteins.
Current controversies in prenatal diagnosis: Expanded NIPT that includes conditions other than trisomies 13, 18, and 21 should be offered
Authors: Christiaens Lieve , Chitty Lyn S. , Langlois Sylvie 
Published: April 2021

AbstractNon‐invasive prenatal testing (NIPT) based on analysis of cell free DNA circulating in the maternal plasma has been available clinically to screen for chromosomal abnormalities since 2011. There is significant evidence to suggest that NIPT has revolutionised prenatal screening for the common trisomies 13, 18, and 21. However, the evidence in favour of its extended use to screen for conditions other than these trisomies remains a topic of debate with no national or international organisation supporting clinical implementation for these indications. In the debate presented here – "Expanded NIPT that includes conditions other than trisomies 13, 18, and 21 should be offered" – we will see the pros and cons of screening for a wider range of chromosomal problems. The discussion presented swung the vote from 65% in favour and 35% against before the arguments were voiced to 41% in favour and 59% against. This significant swing in the vote indicates that the majority of our community feel more evidence is required before clinical implementation of extended NIPT.
Back from the dead (again): The specter of the Fairness Doctrine and its lesson for social media regulation
Authors: Napoli Philip M. 
Published: April 2021

AbstractIn the United States, debates about political bias in the content curation and moderation practices of social media platforms have spilled over into the policy realm, rekindling conversations about the Fairness Doctrine and its potential utility in possible regulatory approaches to social media. This article revisits the history of the Fairness Doctrine and uses this history as a lens for critically examining current proposals for integrating Fairness Doctrine‐like principles into a regulatory framework for social media. In addressing this topic, the first section of this article provides a brief overview of the history of the Fairness Doctrine and how the Doctrine has informed (and misinformed) subsequent media policy debates in the years since its elimination. The second section describes how the Fairness Doctrine is being brought to bear in the contemporary debates around social media regulation. The third section offers a critical analysis of the applicability of the Fairness Doctrine to the social media context.
Correlative imaging for polymer science
Authors: Wang Yuyang , Friedrich Heiner , Voets Ilja K. , Zijlstra Peter , Albertazzi Lorenzo 
Published: April 2021

AbstractThe characterization of polymeric materials is key towards the understanding of structure–activity relations and therefore for the rational design of novel and improved materials for a myriad of applications. Many microscopy techniques are currently used, with electron microscopy, fluorescence microscopy, and atomic force microscopy being the most relevant. In this perspective paper, we discuss the use of correlative imaging, that is, the combination of multiple imaging methodologies on the same sample, in the field of polymeric materials. This innovative approach is emerging as a powerful tool to unveil the structure and functional properties of biological and synthetic structures. Here we discuss the possibilities of correlative imaging and highlight their potential to answer open questions in polymer science.
Enthalpy of Formation of p(BAMO)‐b‐GAP and Energetic Characteristics of Solid Propellants Based on the Copolymer
Authors: Xu Ruoqian , Li Zhongming , Chen Yanhui , Pei Jiangfeng , Zhang Junlin 
Published: April 2021

AbstractThe block copolymer of 3,3’‐bis(azidomethy) oxetane and glycidyl azide polymer (p(BAMO)‐b‐GAP) is an ideal energetic binder for solid propellants. In this work, the enthalpy of formation of p(BAMO)‐b‐GAP was first investigated by the heat of combustion experimental method and group additivity method. Meanwhile, the energetic characteristics of solid propellants based on the copolymer were systematically calculated. The results proved that the ΔfH of p(BAMO)‐b‐GAP could be estimated accurately by two methods and the positive ΔfH values were obtained. Dual‐oxidant formulas were designed in which AP was replaced gradually by some chlorine‐free high‐energy materials. The calculation results showed when AP was gradually replaced by RDX or HMX, the energy level of propellants based on p(BAMO)‐b‐GAP was improved first but then decreased with AP content further decreased, indicating there was an optimum ratio between AP and its alternative. However, when AP was replaced by CL‐20 or ADN, the values of Isp were improved steadily. When less than 40 % AP was replaced, the contribution to the energy level of propellant by RDX or HMX was even more than that by CL‐20.
Exploring Application of 1,2,4‐Triazole Energetic Salts: Gas Generating Agent, Propellant and Explosive Compositions
Authors: Xue Yu‐bing , Xiong Hua‐lin , Tang Jie , Cheng Guang‐bin , Yang Hong‐wei 
Published: April 2021

AbstractHigh‐nitrogen energetic salts as the functional materials could be applied to formulate second explosives, gas‐generating agents, and propellants due to their large gas and energy release after combustion. Herein, a series of the insensitive and highly gas productive 1,2,4‐triazole derivatives including 4,5,5′‐triamine‐3,3′‐bi‐1,2,4‐triazole (1) and 4,5′‐dinitramino‐5‐amine‐3,3′‐bi‐1,2,4‐triazole (4) as well as corresponding salts were synthesized and characterized. The crystal structures of 4,5,5′‐triamine‐3,3′‐bi‐1,2,4‐triazole (1), nitrate salt (2), 4,5′‐dinitramino‐5‐amine‐3,3′‐bi‐1,2,4‐triazole (4) and triaminoguanidine salt (9) were determined by X‐ray diffraction. For explosives candidates, energetic salts of ammonium (5), hydrazinium (6), hydroxylammonium (7), and triaminoguanidine (9) not only display the outstanding detonation performance (D, 8657–9120 m s−1, P, 27.78–33.39 GPa), but also show low mechanical sensitivities (IS≥20 J, FS≥216 N). Furthermore, the constant‐volume combustion experiment results reveal that 5, 6, 7, and 9 show excellent gas productivity (Pmax≥12.8 MPa) and pressure‐up rate (dP/dtmax≥164 GPa s−1). These compounds could be the efficient components of gas‐generating agents and propellants based on the calculated combustion parameters from EXPLO 5 software.
Adenosine triphosphate energy‐independently controls protein homeostasis with unique structure and diverse mechanisms
Authors: Song Jianxing 
Published: April 2021

AbstractProteins function in the crowded cellular environments with high salt concentrations, thus facing tremendous challenges of misfolding/aggregation which represents a pathological hallmark of aging and an increasing spectrum of human diseases. Recently, intrinsically disordered regions (IDRs) were recognized to drive liquid–liquid phase separation (LLPS), a common principle for organizing cellular membraneless organelles (MLOs). ATP, the universal energy currency for all living cells, mysteriously has concentrations of 2–12 mM, much higher than required for its previously‐known functions. Only recently, ATP was decoded to behave as a biological hydrotrope to inhibit protein LLPS and aggregation at mM. We further revealed that ATP also acts as a bivalent binder, which not only biphasically modulates LLPS driven by IDRs of human and viral proteins, but also bind to the conserved nucleic‐acid‐binding surfaces of the folded proteins. Most unexpectedly, ATP appears to act as a hydration mediator to antagonize the crowding‐induced destabilization as well as to enhance folding of proteins without significant binding. Here, this review focuses on summarizing the results of these biophysical studies and discussing their implications in an evolutionary context. By linking triphosphate with unique hydration property to adenosine, ATP appears to couple the ability for establishing hydrophobic, π‐π, π‐cation and electrostatic interactions to the capacity in mediating hydration of proteins, which is at the heart of folding, dynamics, stability, phase separation and aggregation. Consequently, ATP acquired a category of functions at ~mM to energy‐independently control protein homeostasis with diverse mechanisms, thus implying a link between cellular ATP concentrations and protein‐aggregation diseases.
Calcium oxide, potassium phosphite and a Trichoderma enriched compost water suspension protect Capsicum annuum against Phytophthora capsici by priming the immune system
Authors: Bellini Alessio , Pugliese Massimo , Guarnaccia Vladimiro , Meloni Giovanna Roberta , Gullino Lodovica Maria 
Published: April 2021

AbstractBACKGROUNDProper management of Phytophthora capsici in pepper cultivation is extremely important, since Phytophthora blight is the main disease of this crop worldwide. In the past, the main strategy adopted had been the use of fungicides, causing, in some cases, the development of P. capsici resistant strains. In this work three different treatments selected from previous studies (potassium phosphite, calcium oxide and a water suspension from Trichoderma sp. TW2 enriched compost) were tested to prove their ability to activate the systemic acquired resistance (SAR) in pepper against P. capsici; acibenzolar‐s‐methyl was used as positive control. Two independent growth chamber pot experiments were performed, spatially dividing the site of treatments application (as radical drench) and the site of inoculation (as agar plug on the third leaf).RESULTSLeaf lesions were measured, showing a significant reduction on all treated plants compared to the untreated control. To further confirm this hypothesis, the expression levels of three SAR key genes (CaPBR1, CaPO1 and CaDEF1) were evaluated though RT‐Real Time PCR at the three end‐point times: T0, T6 and T24. A significant increase of target genes expression at least in one end‐point time in each treated plant was observed. Eventually, statistical overaccumulation of salicylic acid was observed in the upper leaves at the same end‐point times, through HPLC‐MS/MS analysis.CONCLUSIONThis work confirmed the hypothesis that the three treatments tested have the ability to prime the plant immune system, leading pepper to an alert status able to confer a better defence against P. capsici. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Predictors and prediction skill for marine cold‐air outbreaks over the Barents Sea
Authors: Polkova* Iuliia , Afargan‐Gerstman Hilla , Domeisen Daniela I. V. , King Martin P. , Ruggieri Paolo , Athanasiadis Panos , Dobrynin Mikhail , Aarnes Øivin , Kretschmer Marlene , Baehr Johanna 
Published: April 2021

AbstractMarine cold‐air outbreaks (MCAOs) create conditions for hazardous maritime mesocyclones (polar lows) posing risks to marine infrastructure. For marine management, skilful predictions of MCAOs would be highly beneficial. For this reason, we investigate (a) the ability of a seasonal prediction system to predict MCAOs and (b) the possibilities to improve predictions through large‐scale causal drivers. Our results show that the seasonal ensemble predictions have high prediction skill for MCAOs over the Nordic Seas for about 20 days starting from November initial conditions. To study causal drivers of MCAOs, we utilize a causal effect network approach applied to the atmospheric reanalysis ERA‐Interim and identify local sea surface temperature and atmospheric circulation patterns over Scandinavia as valuable predictors. Prediction skill for MCAOs is further improved up to 40 days by including MCAO predictors in the analysis.
Detection of an appropriate pharmaceutical company to get a suitable vaccine against COVID‐19 with minimum cost under the quality control process
Authors: El‐Hadidy Mohamed Abd Allah , Alfreedi Ajab A. 
Published: April 2021

AbstractSome international pharmaceutical companies have succeeded in producing vaccines against COVID‐19. Countries all over the world have aimed to obtain these vaccines with minimum cost. We consider a set of K‐independent Markovian waiting lists. Each list contains a set of countries, where each one of them has an exponential service time and a Poisson arrival process. These companies differ in some characteristics such as the vaccine production cost and the speed of the required quantity delivery. We present a new detection model that helps in providing an appropriate decision to choose a suitable company. Moreover, the concept of balking and the retention of reneged countries is taken into consideration under the quality control process of each waiting list. Under steady state, we face an interesting and difficult discrete stochastic optimization problem. Its solution gives an optimal distribution of the searching effort, which is bounded by a known probability distribution. A simulation study has been derived to get the minimum value of the paid cost random values. The highest service rate, the total expected profit of each queuing system, and the optimum performance measures, which depend on this cost, have been obtained to show the effectiveness of this model.
Automated detection of Hainan gibbon calls for passive acoustic monitoring
Authors: Dufourq Emmanuel , Durbach Ian , Hansford James P. , Hoepfner Amanda , Ma Heidi , Bryant Jessica V. , Stender Christina S. , Li Wenyong , Liu Zhiwei , Chen Qing , Zhou Zhaoli , Turvey Samuel T. 
Published: April 2021

AbstractExtracting species calls from passive acoustic recordings is a common preliminary step to ecological analysis. For many species, particularly those occupying noisy, acoustically variable habitats, the call extraction process continues to be largely manual, a time‐consuming and increasingly unsustainable process. Deep neural networks have been shown to offer excellent performance across a range of acoustic classification applications, but are relatively underused in ecology. We describe the steps involved in developing an automated classifier for a passive acoustic monitoring project, using the identification of calls of the Hainan gibbon Nomascus hainanus, one of the world's rarest mammal species, as a case study. This includes preprocessing—selecting a temporal resolution, windowing and annotation; data augmentation; processing—choosing and fitting appropriate neural network models; and post‐processing—linking model predictions to replace, or more likely facilitate, manual labelling. Our best model converted acoustic recordings into spectrogram images on the mel frequency scale, using these to train a convolutional neural network. Model predictions were highly accurate, with per‐second false positive and false negative rates of 1.5% and 22.3%. Nearly all false negatives were at the fringes of calls, adjacent to segments where the call was correctly identified, so that very few calls were missed altogether. A post‐processing step identifying intervals of repeated calling reduced an 8‐h recording to, on average, 22 min for manual processing, and did not miss any calling bouts over 72 h of test recordings. Gibbon calling bouts were detected regularly in multi‐month recordings from all selected survey points within Bawangling National Nature Reserve, Hainan. We demonstrate that passive acoustic monitoring incorporating an automated classifier represents an effective tool for remote detection of one of the world's rarest and most threatened species. Our study highlights the viability of using neural networks to automate or greatly assist the manual labelling of data collected by passive acoustic monitoring projects. We emphasize that model development and implementation be informed and guided by ecological objectives, and increase accessibility of these tools with a series of notebooks that allow users to build and deploy their own acoustic classifiers.
Effect of Physical Pretreatments on the Hydrolysis Kinetic, Structural, and Thermal Properties of Pinhão Starch Nanocrystals
Authors: Pinto Vânia Zanella , Moomand Khalid , Deon Vinicius Goncalves , Biduski Barbara , Zavareze Elessandra da Rosa , Lenhani Gabriela Caroline , Fidelis dos Santos Gustavo Henrique , Lim Loong‐Tak , Dias Alvaro Renato Guerra 
Published: April 2021

AbstractStarch nanocrystals (SNCs) are insoluble platelet particles with multifunctional properties. SNCs production is mainly based on acid hydrolysis of cornstarch with low yield. This study focuses on investigating the effect of pretreatments (heat‐moisture‐treatment [HMT], annealing [ANN], and sonication [SNT]) on unconventional pinhão starch to produce SNCs by acid hydrolysis to improve the yield and SNCs properties. All starches hydrolysis is described by a first‐order model reaction and shown two phases related at k values. The faster hydrolysis is from SNT (k = 0.61 day−1) and the slower one is at ANN (k = 0.40 day−1). Furthermore, the acid hydrolysis is described by a rapid (0–2 days) phase, followed by a slow phase lasing 3–7 days. The HMT increases the yield of the SNCs (14.7%) but promotes losses in the RC (47.34%) as compared with the native starch (yield 10.23%; RC 52.23%). The ANN improves crystallites perfection, protecting them from acid attack. The pretreatments allow pinhão starch to be used as promising feedstock to produce SNCs with good yield and RC. In addition, ANN can be useful to improve the thermal stability and SNT to speeding up the hydrolysis for SNCs production, while HMT can increase the hydrolysis yield.