bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of customer awareness on priority queues
Authors: Wang Zhongbin , Fang Lei 
Published: February 2022

AbstractPay‐for‐priority system is believed to be an efficient service mechanism in congested systems since it introduces service differentiation that prioritizes those who are more delay‐sensitive. However, in practice, not all customers are aware of the provision of such auxiliary service (i.e., priority access). Does the lack of awareness or ignorance of priority service make the social welfare or customer surplus worsen off? To answer this question, we establish a queueing‐game‐theoretic model by capturing the strategic interactions between service provider and customers to examine the effect of customer awareness on the priority queues. Our main results are as follows. First, we confirm that increasing the level of customer awareness indeed improves the revenue of service provider, and it triggers a higher priority premium price. Second, perhaps surprisingly, we find that under the profit‐maximizing priority price, the social welfare as well as the customer surplus are both nonmonotone in the level of customer awareness, that is, full or no customer awareness can be suboptimal for the social welfare and customer surplus. Third, despite the common belief that priority is socially efficient in congested systems, we demonstrate that the optimal information levels for social welfare and customer surplus are decreasing in the congestion level, and the full customer awareness is optimal only when the system load is relatively low. Finally, to reach the maximal social welfare or customer surplus, some regulation policies are proposed, whereby the social planner can provide advertising subsidy to (levy tax on) the service provider (advertising agency) when the system load is low (high).
A novel method for solving nonlinear stochastic mechanics problems using FETI‐DP
Authors: Ajith Gopika , Ghosh Debraj 
Published: February 2022

AbstractSolution of large‐scale nonlinear stochastic mechanics problems such as plasticity is generally very expensive. In this work, a domain decomposition based scalable method is proposed for solving such problems. The mechanics problem and random fields are discretized using finite element (FE) bases and Karhunen–Loève expansion, respectively. The FE mesh is partitioned that offers (i) both spatial and stochastic dimensionality reduction and (ii) an inherent framework for parallelization. Then a stochastic collocation based surrogate model is built for each subdomain wherein at each collocation point a deterministic nonlinear problem is solved. The deterministic nonlinear problem is solved using Newton–Raphson method. The linear system of equations involving the Jacobian is solved using the dual‐primal version of the FE tearing and interconnecting (FETI‐DP) method, due to its demonstrated scalability for deterministic problems. Stochastic collocation and FETI‐DP are inherently and independently parallelizable. Finally, at the post‐processing stage, a statistical sampling from the surrogate model is performed by preserving the structure of the input random field. The proposed method is numerically tested for p‐Laplace and plain‐strain plasticity problems, and found to be computationally efficient and accurate. In parallel implementation, the method showed good scalability.
A semi‐relativistic time‐fractional Vlasov–Maxwell code for numerical simulation based on circular polarization and Landau damping instability
Authors: Zubair Tamour , Usman Muhammad 
Published: February 2022

AbstractThe Vlasov–Maxwell system is a revolutionary tool to model and analyze the dynamic behavior of the collisionless plasma in the existence of the electromagnetic field. In this perspective, the investigation of this system with the concept of the time‐fractional derivative is the new benchmark and also one of the main objectives of this article. In order to construct the numerical solution, we propose and implement a novel scheme which grounded on finite‐difference and spectral approximations. The temporal variable is tackled by using finite‐difference approximation, whereas spatial variables approximated via sifted Gegenbauer polynomials. Various simulations are performed to explore new phenomena and demonstrate the accuracy and reliability of the proposed method. Convergence and error bound of the suggested methods are investigated theoretically, whereas stability analysis performed numerically. Moreover, the developed method can be used conveniently to examine the numerical solution of other multidimensional highly nonlinear fractional or variable order problems of physical nature.
Construction of 2D/2D graphene oxide/g‐C3N4 hybrid for enhancing the friction and wear performance of poly (phthalazinone ether sulfone ketone)
Authors: Wang Fenghua , Zhang Mengjie , Li Jiaye , Dong Zhe , Xu Lin , Wang Shuang , Zhang Kan , Chen Beibei 
Published: February 2022

AbstractIn this study, a novel hybrid consisted of two‐dimensional graphene oxide (GO) and graphitic carbon nitride (g‐C3N4) nanosheets were fabricated to improve the tribological performance of poly (phthalazinone ether sulfone ketone) (PPESK). The effect of the mass ratio of GO to g‐C3N4 (1:1, 1:2, and 1:3) on the microstructure of GO/g‐C3N4 was firstly studied. As the ratio was 1:2 (GO/g‐C3N4‐2), the g‐C3N4 could be homogeneously distributed on surface of GO, and the corresponding hybrid possessed many active sites. Moreover, the effect of GO/g‐C3N4 hybrid, GO, and g‐C3N4 on the tribological properties of PPESK matrix was explored systematically. Results showed that GO/g‐C3N4 demonstrated more excellent reinforcing and lubricating effect than single GO and g‐C3N4, especially for GO/g‐C3N4‐2. More importantly, as the content of GO/g‐C3N4‐2 was 0.1 wt%, the antifriction and anti‐wear performance of PPESK was improved by 77.28% and 96.9%, respectively. Moreover, the enhancement mechanisms of GO/g‐C3N4 on the tribological behaviors of PPESK were clarified by analyzing the surface morphology of the composite and the counterpart. This work might provide the guidance for the design of a novel nano‐hybrid material applied in polymer self‐lubricating composites.
Efficient polymerization and crystallization kinetics coupling of polyamide 6 synthesis for liquid composite molding process modeling
Authors: Han William , Govignon Quentin , Cantarel Arthur , Schmidt Fabrice 
Published: February 2022

AbstractVariabilities in polyamide 6 (PA6) composite manufacturing by liquid processes can occur due to polymerization, crystallization, and flow through a fibrous preform. Numerical simulations of the process predicting the kinetics can facilitate manufacturing optimization. This study proposes an efficient modeling approach that can be integrated in current simulation discretization methods such as the finite volume method (FVM) while considering the interaction between PA6 polymerization and crystallization. Using polymerization and crystallization models issued from the literature, a previous study determined Hillier coupling method to be able to predict PA6 kinetics. A simpler and more efficient coupling will be introduced and adapted to account for process variability. It was integrated into an FVM framework for process simulation of injection showcasing the capabilities of the model to predict potential crystallization discrepancies.
The Significant Influence of the pH Value on Citrate Coordination upon Modification of Superparamagnetic Iron Oxide Nanoparticles
Authors: Granath Tim , Mandel Karl , Löbmann Peer 
Published: February 2022

AbstractAlthough citrates are commonly used to modify nanoparticles, attention is rarely paid to how the modification parameters affect the type of adsorption and, thus, possibly, the properties of the modified particles. The relevance of this and the significant impact it can have is demonstrated in this study by examining the effect of pH upon the modification of superparamagnetic iron oxide nanoparticles (SPIONs) with citrate, using a citrate concentration that yields a high molecular surface density but induces almost no coordination pressure. Relying first on a number of classical surfaces analyzing methods, no clear pH‐dependent differences can be identified. Finally, the consideration of the thermally induced redox behavior gives a decisive clue to unravel the “citric acid mystery” and to put together the, until then, weak hints into an overall picture. This shows that the citrate carboxyl groups are linked to the oxidic surface pH dependently via hydrogen bonds to hydroxide groups or coordinatively to iron ions and, besides, also interact, to a certain extent, with ammonia that is used for pH adjustment. With these findings, it is finally possible to explain the observed differences when the citrate‐modified SPIONs are coated with silica (SiO2) or redispersed after spray‐drying.
Fluorescent lymphography for thoracic duct identification: Initial experience of a simplified and feasible ICG administration
Authors: Barbato Giuseppe , Cammelli Francesca , Braccini Giovanni , Staderini Fabio , Cianchi Fabio , Coratti Francesco 
Published: February 2022

AbstractIntroductionIndocyanine green (ICG) lymphography can be performed to obtain realtime fluorescent images of the thoracic duct (TD). The injection of ICG into the inguinal nodes usually is ultrasound‐guided. Our hypothesis was to simplify the ICG administration until making it executable by unqualified personnel without ultrasound guidance.Material and methodsFrom October 2019 to October 2021 we enroled 18 patients. ICG was injected with a 25 Gauge needle in the subcutaneous tissue of the inguinal region bilaterally 14–16 h before surgery.ResultsThe TD was visualised in every case considered. The easy switching between fluorescence and white light visualization facilitated the identification and dissection of the TD avoiding involuntary injuries.ConclusionsThe simplified ICG administration to identify TD during oesophagectomy is easy to perform, does not require specifically trained staff, is not time demanding and has comparable results to the procedure performed under ultrasound guide.
DNA methylation in blood cells is associated with cortisol levels in offspring of mothers who had prenatal post‐traumatic stress disorder
Authors: Fransquet Peter Daniel , Hjort Line , Rushiti Feride , Wang Shr‐Jie , Krasniqi Sebahate Pacolli , Çarkaxhiu Selvi Izeti , Arifaj Dafina , Xhemaili Vjosa Devaja , Salihu Mimoza , Leku Nazmie Abullahu , Ryan Joanne 
Published: February 2022

AbstractMaternal stress during pregnancy is associated with differential DNA methylation in offspring and disrupted cortisol secretion. This study aimed to determine methylation signatures of cortisol levels in children, and whether associations differ based on maternal post‐traumatic stress disorder (PTSD). Blood epigenome‐wide methylation and fasting cortisol levels were measured in 118 offspring of mothers recruited from the Kosovo Rehabilitation Centre for Torture Victims. Mothers underwent clinically administered assessment for PTSD using Diagnostic and Statistical Manual of Mental Disorders. Correlations between offspring methylation and cortisol levels were examined using epigenome‐wide analysis, adjusting for covariates. Subsequent analysis focussed on a priori selected genes involved in the hypothalamic–pituitary–adrenal (HPA) axis stress signalling. Methylation at four sites were correlated with cortisol levels (cg15321696, r = −0.33, cg18105800, r = +0.33, cg00986889, r = −0.25, and cg15920527, r = −0.27). In adjusted multivariable regression, when stratifying based on prenatal PTSD status, significant associations were only found for children born to mothers with prenatal PTSD (p < 0.001). Several sites within HPA axis genes were also associated with cortisol levels in the maternal PTSD group specifically. There is evidence that methylation is associated with cortisol levels, particularly in offspring born to mothers with prenatal PTSD. However, larger studies need to be carried out to independently validate these findings.
Chemical Approaches to Carbocyclic Nucleosides
Authors: Ojeda‐Porras Andrea C. , Roy Vincent , Agrofoglio Luigi A. 
Published: February 2022

AbstractNucleoside analogues are at the forefront of antiviral therapy for last decades. To circumvent some of their limitations, based on their metabolism, and in order to improve their anti‐viral potency and selectivity, several families of nucleoside analogues have been described through structural modifications at the sugar and heterocycles. The replacement of the oxygen of the nucleoside by a methylene has led to the family of carbocyclic (or cyclopentane) nucleoside analogues. Various potent anti‐HIV and anti‐HBV drugs belong to this family. Main syntheses of carbocyclic analogues of nucleosides used Diels‐Alder reactions (in racemic or asymmetric series), but also started from carbohydrates (ribose, glucose), as a source of optically active compounds, which then had to be transformed into carbacycles under various conditions. The growing interest in carbocyclic nucleosides has led several groups, including ours, to develop new analogues and to explore novel routes. This article will review some of the recent chemistry developed on selected five‐membered ring carbocyclic nucleosides.
Synthesis of Nucleobase‐Modified Oligonucleotides by Post‐Synthetic Modification in Solution
Authors: Ito Yuta , Hari Yoshiyuki 
Published: February 2022

AbstractOligonucleotides containing modified nucleobases have applications in various technologies. In general, to synthesize oligonucleotides with different nucleobase structures, each modified phosphoramidite monomer needs to be prepared over multiple steps and then introduced onto the oligonucleotides, which is time‐consuming and inefficient. Post‐synthetic modification is a powerful strategy for preparing many types of modified oligonucleotides, especially nucleobase‐modified ones. Depending on the stage of modification, post‐synthetic modification can be divided into two stages: “solid‐phase modification,” wherein an oligonucleotide attaches to the resin, and “solution‐phase modification,” wherein an oligonucleotide detaches itself from the resin. In this review, we focus on post‐synthetic modification in solution for the synthesis of nucleobase‐modified oligonucleotides, except the modifications to linkers for conjugation. Moreover, the reactions are summarized for each modified position of the nucleobases.
Metal‐Organic Frameworks Derived Electrocatalysts for Oxygen and Carbon Dioxide Reduction Reaction
Authors: Najam Tayyaba , Ahmad Khan Naseem , Ahmad Shah Syed Shoaib , Ahmad Khalil , Sufyan Javed Muhammad , Suleman Suleman , Sohail Bashir Muhammad , Hasnat Mohammad A. , Rahman Mohammed M. 
Published: February 2022

AbstractThe increasing demands of energy and environmental concerns have motivated researchers to cultivate renewable energy resources for replacing conventional fossil fuels. The modern energy conversion and storage devices required high efficient and stable electrocatalysts to fulfil the market demands. In previous years, we are witness for considerable developments of scientific attention in Metal‐organic Frameworks (MOFs) and their derived nanomaterials in electrocatalysis. In current review article, we have discussed the progress of optimistic strategies and approaches for the manufacturing of MOF‐derived functional materials and their presentation as electrocatalysts for significant energy related reactions. MOFs functioning as a self‐sacrificing template bid different benefits for the preparation of metal nanostructures, metal oxides and carbon‐abundant materials promoting through the porous structure, organic functionalities, abundance of metal sites and large surface area. Thorough study for the recent advancement in the MOF‐derived materials, metal‐coordinated N‐doped carbons with single‐atom active sites are emerging candidates for future commercial applications. However, there are some tasks that should be addressed, to attain improved, appreciative and controlled structural parameters for catalytic and chemical behavior.
Cytopathological and bacteriological studies on caseous lymphadenitis in cattle slaughtered at Bishoftu municipal abattoir, Ethiopia
Authors: Mathewos Mesfin , Fesseha Haben 
Published: February 2022

AbstractBackgroundCaseous lymphadenitis (CLA) is a chronic bacterial infectious disease that affects cattle, shoats, and other domestic and wild ruminants.MethodsA purposive cross‐sectional study was conducted on 30 cattle with enlarged lymph nodes to investigate CLA using cytopathological and bacteriological techniques from cattle slaughtered at Bishoftu municipal abattoir.ResultsFrom a total of 30 cattle subjected to clinical and post‐mortem examinations, only one bull was found to be infected with a rare case of CLA in Bishoftu municipal abattoir, Ethiopia. Enlargement of the pre‐scapular lymph node was the only clinical finding during ante‐mortem inspection of the bull. The gross pathological lesion showed a pre‐scapular lymph node with a caseo‐necrotic dystrophic calcification that was accompanied by a rough texture and white to grayish hue. Histopathologically, the lymph node was characterized by central liquefactive necrosis that was surrounded by coagulative necrosis containing multiple foci of mineralization, infiltration of polymorphonuclear neutrophils and mononuclear immature fibrosis containing inflammatory cells and also with some sort of a thick layer of mature fibrosis that defines the magnitude of the lesion. Cytologically, multi‐lobulated (intact and degenerated) neutrophils, a few reactive lymphocytes, macrophages and some crenated histocytes have been recognized. The bacterial culture of the sample revealed small, white cream, dry, waxy colonies with a narrow area of β‐haemolysis. The isolate of the sample was a Gram‐positive cocci‐bacilli that was arranged in a Chinese pattern on Gram staining, and catalase and urease were positive in the biochemical analysis of this organism, which was able to ferment glucose and maltose but not trehalose and xylose.ConclusionsThe present investigation indicated that CLA was prevalent as sporadic cases among cattle slaughtered in Bishoftu municipal abattoir. Thus, effective preventive and control measures, such as good sanitation and hygiene, should be followed during meat inspection.
Natural carbon removal as technology
Authors: Markusson Nils 
Published: February 2022

AbstractLay people tend to prefer natural solutions for carbon removal over technological ones. Researchers have argued that all carbon removal methods can be seen as “natural.” Here I argue that it is also in practice necessary to see all carbon removal methods as “technological,” that is, standardized, engineered, machine‐like, enclosed systems. Natural carbon removal methods are complex socio‐natural‐technical messy systems that interact in complex ways with their environments. But to work well in practice as an option in climate policy—including in any emissions trading or offsetting schemes—they simultaneously need to be framed in much narrower terms, to be accountable (modellable, tradeable). And there will be efforts to not just frame, but physically make natural carbon removal as standardized, engineered, machine‐like and enclosed as possible—although doomed to never be fully successful. It is in these senses that all carbon removal is technological. The ambiguity between an often vague framing as natural, a narrowly technological framing, and a wider socio‐natural‐technical framing, matters for public understanding and acceptance. Would lay publics still prefer natural solutions to carbon removal, if they are informed about the inevitable technological framing and shaping of them? Research is needed about this. It also matters for the risk of mitigation deterrence. Previous research shows that the narrow framing, of carbon removal methods as technology is implicated in societal processes that deter efforts to reduce greenhouse gas emissions.This article is categorized under:
Social Status of Climate Change Knowledge > Knowledge and Practice
Social Status of Climate Change Knowledge > Sociology/Anthropology of Climate Knowledge
Climate, History, Society, Culture > Technological Aspects and Ideas
Calabi-Yau CFTs and random matrices
Authors: Afkhami-Jeddi Nima , Ashmore Anthony , Córdova Clay 
Published: February 2022

Abstract
Using numerical methods for finding Ricci-flat metrics, we explore the spectrum of local operators in two-dimensional conformal field theories defined by sigma models on Calabi-Yau targets at large volume. Focusing on the examples of K3 and the quintic, we show that the spectrum, averaged over a region in complex structure moduli space, possesses the same statistical properties as the Gaussian orthogonal ensemble of random matrix theory.
Supertranslations at timelike infinity
Authors: Chakraborty Sumanta , Ghosh Debodirna , Hoque Sk Jahanur , Khairnar Aniket , Virmani Amitabh 
Published: February 2022

AbstractWe propose a definition of asymptotic flatness at timelike infinity in four spacetime dimensions. We present a detailed study of the asymptotic equations of motion and the action of supertranslations on asymptotic fields. We show that the Lee-Wald symplectic form Ω(g, δ1g, δ2g) does not get contributions from future timelike infinity with our boundary conditions. As a result, the “future charges” can be computed on any two-dimensional surface surrounding the sources at timelike infinity. We present expressions for supertranslation and Lorentz charges.
A note on imputing squares via polynomial combination approach
Authors: Cai Mingyang , Vink Gerko 
Published: February 2022

AbstractThe polynomial combination (PC) method, proposed by Vink and Van Buuren, is a hot-deck multiple imputation method for imputation models containing squared terms. The method yields unbiased regression estimates and preserves the quadratic relationships in the imputed data for both MCAR and MAR mechanisms. However, Vink and Van Buuren never studied the coverage rate of the PC method. This paper investigates the coverage of the nominal 95% confidence intervals for the polynomial combination method and improves the algorithm to avoid the perfect prediction issue. We also compare the original and the improved PC method to the substantive model compatible fully conditional specification method proposed by Bartlett et al. and elucidate the two imputation methods’ characters.