bluuebunny/crossref_metadata_2025 huggingface dataset:
Nitrogen Poisoning of HDPE and LLDPE based on Chemically Recycled Post‐Consumer Plastic via a Kinetic and Microstructural Modeling Technique
Authors: Pernusch Daniel C. , Spiegel Gunnar , Paulik Christian , Hofer Wolfgang
Published: April 2022

Chemical recycling of plastic waste has promise as a complementary technology to increase eco‐efficiency of plastics life cycles. Accumulation of impurities in feed streams can affect sensitive compounds such as the Ziegler–Natta catalyst systems commonly used to produce polyolefins such as high density polyethylene (HDPE) and linear low density polyethylene (LLDPE). In a poison study, the influence of impurities—more specifically NO and N2O—on the catalyst system are investigated comprehensively in terms of kinetic behavior and activity rates. A product composition analysis gives insights into product properties such as molecular weight distribution (MWD), comonomer composition distribution (CCD), melting point, and crystallinity. By applying known modeling techniques (kinetic modeling, MWD, and CCD deconvolution modeling), information beyond analytical data is obtained. The results of the study show that both poisons significantly affect catalyst kinetics and reduce catalyst activity. N2O influences primarily the MWD, while NO poisoning strongly affects the CCD of LLDPE samples. Since the mechanical properties of the polymers produced depend on factors such as MWD and CCD, NO and N2O poisoning may reduce their processability and applicability.
Blip up‐down acquisition for spin‐ and gradient‐echo imaging (BUDA‐SAGE) with self‐supervised denoising enables efficient T2, T2*, para‐ and dia‐magnetic susceptibility mapping
Authors: Zhang Zijing , Cho Jaejin , Wang Long , Liao Congyu , Shin Hyeong‐Geol , Cao Xiaozhi , Lee Jongho , Xu Jinmin , Zhang Tao , Ye Huihui , Setsompop Kawin , Liu Huafeng , Bilgic Berkin
Published: April 2022

Purpose

To rapidly obtain high resolution T2, T2*, and quantitative susceptibility mapping (QSM) source separation maps with whole‐brain coverage and high geometric fidelity.

Methods

We propose Blip Up‐Down Acquisition for Spin And Gradient Echo imaging (BUDA‐SAGE), an efficient EPI sequence for quantitative mapping. The acquisition includes multiple T2*‐, T2′‐, and T2‐weighted contrasts. We alternate the phase‐encoding polarities across the interleaved shots in this multi‐shot navigator‐free acquisition. A field map estimated from interim reconstructions was incorporated into the joint multi‐shot EPI reconstruction with a structured low rank constraint to eliminate distortion. A self‐supervised neural network (NN), MR‐Self2Self (MR‐S2S), was used to perform denoising to boost SNR. Using Slider encoding allowed us to reach 1 mm isotropic resolution by performing super‐resolution reconstruction on volumes acquired with 2 mm slice thickness. Quantitative T2 (=1/R2) and T2* (=1/R2*) maps were obtained using Bloch dictionary matching on the reconstructed echoes. QSM was estimated using nonlinear dipole inversion on the gradient echoes. Starting from the estimated R2/R2* maps, R2′ information was derived and used in source separation QSM reconstruction, which provided additional para‐ and dia‐magnetic susceptibility maps.

Results

In vivo results demonstrate the ability of BUDA‐SAGE to provide whole‐brain, distortion‐free, high‐resolution, multi‐contrast images and quantitative T2/T2* maps, as well as yielding para‐ and dia‐magnetic susceptibility maps. Estimated quantitative maps showed comparable values to conventional mapping methods in phantom and in vivo measurements.

Conclusion

BUDA‐SAGE acquisition with self‐supervised denoising and Slider encoding enables rapid, distortion‐free, whole‐brain T2/T2* mapping at 1 mm isotropic resolution under 90 s.
Smoothed aggregation for difficult stretched mesh and coefficient variation problems
Authors: Hu Jonathan J. , Siefert Christopher M. , Tuminaro Raymond S.
Published: April 2022

Four adaptations of the smoothed aggregation algebraic multigrid (SA‐AMG) method are proposed with an eye toward improving the convergence and robustness of the solver in situations when the discretization matrix contains many weak connections. These weak connections can cause higher than expected levels of fill‐in within the coarse discretization matrices and can also give rise to suboptimal smoothing within the prolongator smoothing phase. These smoothing drawbacks are due to the relatively small size of some diagonal entries within the filtered matrix that one obtains after dropping the weak connections. The new algorithms consider modifications to the Jacobi‐like step that defines the prolongator smoother, modifications to the filtered matrix, and also direct modifications to the resulting grid transfer operators. Numerical results are given illustrating the potential benefits of the proposed adaptations.
A parallel finite volume method for incompressible and slightly compressible reactive flows
Authors: de Andrade Henrique C. C. , Ribeiro Fernando L. B. , Carlos Wrobel Luiz
Published: April 2022

In this article, a parallel formulation of the finite volume method is presented for solving three‐dimensional, turbulent, mixed, reactive, and slightly compressible flows. It can also be used for incompressible laminar/turbulent flows. The method is designed for nonorthogonal meshes, and oscillations caused by the advective terms are treated by a deferred correction technique. The chosen finite volume scheme is cell centered. The studied fluid is a single‐phase multicomponent gas with Newtonian behavior. The focus is mainly on gas mixtures with predominance of N, since the chemical reaction of greatest interest is the combustion process in the air. The buoyancy is caused by the gradient of the specified mass, which is a function of the temperature and the composition of the gas mixture. The mathematical model uses an approximation for low Mach numbers, describing slightly compressible flows. The coupling between the fluid dynamic equations is given by the nonlinear Picard's method, with the pressure‐velocity coupling treatment given by the SIMPLE algorithm (semi‐implicit method for pressure‐linked equations). The complete mathematical model includes the sensitive enthalpy equation for the conservation of energy. The LES (large eddy simulation) model is used for modeling the turbulence. The chemical reactions are implemented using the EDC (eddy dissipation concept) and the EDM (eddy dissipation model) approaches. The parallel strategy is based on a subdomain‐by‐subdomain approach, and uses the MPI and OpenMP standards in a hybrid parallel scheme. Compressed data structures are used to store the matrix coefficients.
Analysis of the frequency distribution of five single‐nucleotide polymorphisms of the MTRRgene in a Chinese pediatric population with acute lymphoblastic leukemia
Authors: Li Miao , Kong Xiao‐Yan , Wang Shu‐Mei
Published: April 2022

Study Objective

The objective of the present study was to examine the frequency distribution of five single‐nucleotide polymorphisms (SNPs; rs1801394 A>G, rs1532268 C>T, rs162036 A>G, rs10380 C>T, and rs9332 C>T) of the methionine synthase reductase (MTRR) gene, their effects on methotrexate (MTX) concentration, and the risk of relapse in a Chinese pediatric population with acute lymphoblastic leukemia (ALL).

Design

This was a retrospective single‐center study, and all analyses were exploratory.

Setting

Pediatric Department of Beijing Shijitan Hospital, Capital Medical University, Beijing, China.

Patients

One hundred and forty pediatric patients with ALL.

Intervention

All patients were treated according to the Chinese Children's Leukemia Group (CCLG)‐ALL 2008 protocol.

Measurements and Main Results

Serum MTX concentrations were measured using fluorescence polarization immunoassay. Genotyping of five SNPs was performed using the Sequenom MassARRAY iPLEX platform. Chinese children with ALL had a significantly lower frequency of rs1801394 G than European (EUR) and South Asian (SAS) populations; significantly lower frequency of rs1532268 T than American (AMR), EUR, and SAS populations; and significantly lower frequencies of rs162036 G, rs10380 T, and rs9332 T than African and AMR populations (p < 0.01). Seven haplotypes were observed, with the ACACC being the most common haplotype (49.9%) in our study. The median dose‐normalized concentrations of MTX in serum at 24 h in children with rs1532268 CT and TT genotypes were significantly higher than those with CC genotype (p = 0.04). Compared with children with AA‐CC‐AA‐CC‐CC diplotype, a significantly higher risk of relapse was observed in children with AG‐CC‐AA‐CC‐CC and AG‐CC‐AG‐CC‐CC diplotypes (p = 0.03 and 0.003, respectively).

Conclusions

The present study confirmed the ethnic differences in the distribution of MTRR rs1801394, rs1532268, rs162036, rs10380, and rs9332 polymorphisms. The rs1532268 polymorphism had greater effects on MTX disposition. The AG‐CC‐AA‐CC‐CC and AG‐CC‐AG‐CC‐CC diplotypes were significantly associated with higher risk of relapse of ALL.
PCNA from Thermococcus gammatolerans: A protein involved in chromosomal DNA metabolism intrinsically resistant at high levels of ionizing radiation
Authors: Marín‐Tovar Yerli , Serrano‐Posada Hugo , Díaz‐Vilchis Adelaida , Rudiño‐Piñera Enrique
Published: April 2022

Proliferating cell nuclear antigen (PCNA) is an essential protein for cell viability in archaea and eukarya, since it is involved in DNA replication and repair. In order to obtain insights regarding the characteristics that confer radioresistance, the structural study of the PCNA from Thermococcus gammatolerans (PCNATg) in a gradient of ionizing radiation by X‐ray crystallography was carried out, together with a bioinformatic analysis of homotrimeric PCNA structures, their sequences, and their molecular interactions. The results obtained from the datasets and the accumulated radiation dose for the last collection from three crystals revealed moderate and localized damage, since even with the loss of resolution, the electron density map corresponding to the last collection allowed to build the whole structure. Attempting to understand this behavior, multiple sequence alignments, and structural superpositions were performed, revealing that PCNA is a protein with a poorly conserved sequence, but with a highly conserved structure. The PCNATg presented the highest percentage of charged residues, mostly negatively charged, with a proportion of glutamate more than double aspartate, lack of cysteines and tryptophan, besides a high number of salt bridges. The structural study by X‐ray crystallography reveals that the PCNATg has the intrinsic ability to resist high levels of ionizing radiation, and the bioinformatic analysis suggests that molecular evolution selected a particular composition of amino acid residues, and their consequent network of synergistic interactions for extreme conditions, as a collateral effect, conferring radioresistance to a protein involved in the chromosomal DNA metabolism of a radioresistant microorganism.
Wafer‐Scale Demonstration of MBC‐FET and C‐FET Arrays Based on Two‐Dimensional Semiconductors
Authors: Xia Yin , Zong Lingyi , Pan Yu , Chen Xinyu , Zhou Lihui , Song Yiwen , Tong Ling , Guo Xiaojiao , Ma Jingyi , Gou Saifei , Xu Zihan , Dai Sheng , Zhang David Wei , Zhou Peng , Ye Yu , Bao Wenzhong
Published: April 2022

Two‐dimentional semiconductors have shown potential applications in multi‐bridge channel field‐effect transistors (MBC‐FETs) and complementary field‐effect transistors (C‐FETs) due to their atomic thickness, stackability, and excellent electrical properties. However, the exploration of MBC‐FET and C‐FET based on large‐scale 2D semiconductors is still lacking. Here, based on a reliable vertical stacking of wafer‐scale 2D semiconductors, large‐scale MBC‐FETs and C‐FETs using n‐type MoS2 and p‐type MoTe2 are successfully fabricated. The drive current of an MBC‐FET with two layers of MoS2 channel (20 µm/10 µm) is up to 60 µA under 1 V bias. Compared with the single‐gate MoS2 FET, the carrier mobility of MBC‐FET is 2.3 times higher and the sub‐threshold swing is 70% smaller. Furthermore, NAND and NOR logic circuits are also constructed based on two vertically stacked MoS2 channels. Then, C‐FET arrays are fabricated by 3D integrating n‐type MoS2 FET and p‐type MoTe2 FET, which exhibit a voltage gain of 7 V/V when VDD = 4 V. In addition, this C‐FET device can directly convert light signals to an electrical digital signal within a single device. The demonstration of MBC‐FET and C‐FET based on large‐scale 2D semiconductors will promote the application of 2D semiconductors in next‐generation circuits.
Xenon Ion Implantation Induced Surface Compressive Stress for Preventing Dendrite Penetration in Solid‐State Electrolytes
Authors: Yao Xuhui , Olsson Emilia , Wang Manman , Wang Jianan , Cai Qiong , Peng Nianhua , Webb Roger , Zhao Yunlong
Published: April 2022

Solid‐state electrolytes (SSEs) have been thrust into the limelight for the revival of energy‐dense lithium metal batteries, but still face the challenge of failure caused by the dendrite penetration. Mounting evidence indicates that dendrite penetration is related to the mechanical failure in SSEs, which calls for mechanical engineering to tackle this problem. This work reports a proof of concept that ion implantation induced surface compressive stress enables resistance in the dendrite penetration. A deterministic sequential multiple ion energies implantation is used to generate compressive stress, with implanted Xe ions distributed in a range of 160–600 Å from the surface. The symmetric lithium cells show that pellets with an implantation dose of 1013 Xe cm−2 exhibit stable stripping/plating cycles and extended lifespan, while a lower dose of 1012 Xe cm−2 cannot create sufficient stress to prevent dendrite penetration, and an excessive dose of 1014 Xe cm−2 leads to structural destruction and a decrease in stress. This improved performance is attributed to the induced surface compressive stress balanced over crystal grains, which is confirmed by grazing incidence diffraction techniques. The author's efforts demonstrate the usefulness of surface compressive stress to suppress dendrite penetration, offering more insight into rational stress–strain engineering as opposed to empirical optimization.
Peptidomic analysis of mycobacterial secreted proteins enables species identification
Authors: Shu Qingbo , Rajagopal Meena , Fan Jia , Zhan Lingpeng , Kong Xiangxing , He Yifan , Rotcheewaphan Suwatchareeporn , Lyon Christopher J. , Sha Wei , Zelazny Adrian M. , Hu Tony
Published: April 2022

Pulmonary disease arising from slow‐growing mycobacterial infections has emerged as an increasingly prevalent clinical concern over the past two to three decades. Proteins belonging to the family of ESAT‐6 secretion (Esx) systems play critical roles in the virulence of most pathogenic mycobacterial species and are associated with drug resistance. However, no clinical applications can detect and discriminate the expression of species‐specific variants of these proteins in clinical samples, such as early growth cultures, for rapid diagnosis of specific mycobacterial infections, which may require distinct interventions. Conventional immunoassay approaches are not suitable for this purpose due to the significant degree of conservation of Esx proteins among species. Herein we describe the development of a novel immunoprecipitation‐coupled mass spectrometry assay that can distinguish Esx proteins that are expressed by slow‐growing mycobacterial species commonly detected in clinical isolates. This approach uses custom antibodies raised against single semi‐conserved peptide regions in M. tuberculosis (Mtb) EsxB and EsxN to capture corresponding peptides from protein orthologs of mycobacteria associated with human respiratory infections, including Mtb, M. avium, M. intracellulare, M. kansasii, M. gordonae, and M. marinum, to detect these species in standard clinical cultures at the first sign mycobacterial growth to allow rapid disease diagnosis.
A multimodal nanoparticles‐based theranostic method and system
Authors: Gannot Israel
Published: April 2022

We propose a nanoparticles‐based system for the early detection of tumors, treatment under real‐time feedback, and monitoring. The building blocks of the system comprise a few modalities that are integrated into one powerful system which can operate at the patient's bedside in an outpatient clinic setting. The method relies on the unique characteristics of superparamagnetic nanoparticles. It takes advantage of their ability to produce acoustical signals under alternating magnetic fields (AMFs) and to produce heat under these same AMFs with different parameters. It utilizes the nanoparticles' coating for specific binding. The manuscript describes the various parts of this method for localization, source separation, confined heat elevation, triggering of cell death, and monitoring the response to treatment through fluorescence signaling. The entire system continues to evolve into a minimally invasive trans‐endoscopic set‐up.

This article is categorized under:

Diagnostic Tools > In Vivo Nanodiagnostics and Imaging

Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease
Ergebnisse zu Studie 1
Authors: Hettmann Maximilian
Published: April 2022

Zur Auswertung des Wissenstests zum pädagogisch-psychologischen Wissen wurden die Punktescores der zwanzig Einzelitems zu einem Gesamtscore addiert. Dieser konnte maximal 80 Punkte und minimal – 60 Punkte erreichen. In der Tabelle 10.1 sind die Verläufe der beiden Untersuchungsgruppen zwischen den Messzeitpunkten (T1 und T2) dargestellt.
Zusammenfassende Diskussion Ergebnisse von Studie 1
Authors: Hettmann Maximilian
Published: April 2022

Die Förderung von Motivation ist vor dem Hintergrund der besonderen motivationalen Bedingungen von Schüler*innen mit Schwierigkeiten beim Mathematiklernen ein wichtiges Element der alltäglichen Tätigkeit von Mathematiklehrkräften. Diese Arbeit leistet einen Beitrag dazu, die hinter motivationsförderlichem Lehrer*innenhandeln stehenden kognitiven und affektiv-motivationalen Dispositionen zu identifizieren und einen Ansatz für deren Förderung zu entwickeln. Auf Basis einer Anforderungsanalyse für die Motivationsförderung von Schüler*innen mit Schwierigkeiten beim Mathematiklernen in Fördersettings wurde theoriebasiert ein Modell der professionellen Kompetenz, motiviertes Lernen zu fördern entwickelt und begründet.
Zusammenfassung und Ausblick
Authors: Hettmann Maximilian
Published: April 2022

In dieser Arbeit wurden professionelle Kompetenzen von angehenden Mathematiklehrkräften zur Förderung von Mathematiklernen unter der Berücksichtigung individueller Motivation untersucht. Dazu wurde zunächst der aktuelle Forschungsstand zur Förderung von mathematischen Kompetenzen und motivationalen Variablen sowie zur Unterrichtsqualität bei Schüler*innen mit Schwierigkeiten mit dem Mathematiklernen dargelegt und Grundsätze der Förderung dieser Schüler*innengruppe formuliert (s. Abbildung 2.3).
Mathematiklernen und Motivation bei Schüler*innen mit Lernschwierigkeiten
Authors: Hettmann Maximilian
Published: April 2022

Schulische Lernprozesse sind abhängig von zahlreichen Faktoren. Helmke (2017) stellt mit dem Angebots-Nutzungs-Modell einen strukturellen Rahmen vor, der diese Zusammenhänge auf empirischer Basis in ein Bedingungsgefüge setzt (vgl. S. 71).
Studiendesign
Authors: Hettmann Maximilian
Published: April 2022

Zur Beantwortung der dargestellten Forschungsfragen wurde ein komplexes Untersuchungsdesign entwickelt. Da der organisatorische Rahmen für beide Studien identisch ist, wird er nur in diesem Kapitel referiert. Die wichtigen Aspekte für die zweite Studie werden dann an entsprechender Stelle (Abschnitt 12.1) hervorgehoben.
Auswertungsmethode für Studie 1
Authors: Hettmann Maximilian
Published: April 2022

Die Beschreibung der Auswertungsmethodik für die erhobenen Daten folgt der Gliederung durch die fünf Forschungsfragen.
Analytic and asymptotically flat hairy (ultra-compact) black-hole solutions and their axial perturbations
Authors: Bakopoulos Athanasios , Nakas Theodoros
Published: April 2022

Abstract

In this work, we consider a very simple gravitational theory that contains a scalar field with its kinetic and potential terms minimally coupled to gravity, while the scalar field is assumed to have a coulombic form. In the context of this theory, we study an analytic, asymptotically flat, and regular (ultra-compact) black-hole solutions with non-trivial scalar hair of secondary type. At first, we examine the properties of the static and spherically symmetric black-hole solution — firstly appeared in [109] — and we find that in the causal region of the spacetime the stress-energy tensor, needed to support our solution, satisfies the strong energy conditions. Then, by using the slow-rotating approximation, we generalize the static solution into a slowly rotating one, and we determine explicitly its angular velocity ω(r). We also find that the angular velocity of our ultra-compact solution is always larger compared to the angular velocity of the corresponding equally massive slow-rotating Schwarzschild black hole. In addition, we investigate the axial perturbations of the derived solutions by determining the Schrödinger-like equation and the effective potential. We show that there is a region in the parameter space of the free parameters of our theory, which allows for the existence of stable ultra-compact black hole solutions. Specifically, we calculate that the most compact and stable black hole solution is 0.551 times smaller than the Schwarzschild one, while it rotates 2.491 times faster compared to the slow-rotating Schwarzschild black hole. Finally, we present without going into details the generalization of the derived asymptotically flat solutions to asymptotically (A)dS solutions.
Formalizing Geometric Algebra in Lean
Authors: Wieser Eric , Song Utensil
Published: April 2022

This paper explores formalizing Geometric (or Clifford) algebras into the Lean 3 theorem prover, building upon the substantial body of work that is the Lean mathematics library, . As we use Lean source code to demonstrate many of our ideas, we include a brief introduction to the Lean language targeted at a reader with no prior experience with Lean or theorem provers in general. We formalize the multivectors as the quotient of the tensor algebra by a suitable relation, which provides the ring structure automatically, then go on to establish the universal property of the Clifford algebra. We show that this is quite different to the approach taken by existing formalizations of Geometric algebra in other theorem provers; most notably, our approach does not require a choice of basis. We go on to show how operations and structure such as involutions, versors, and the $$\mathbb {Z}_2$$

Z
2

-grading can be defined using the universal property alone, and how to recover an induction principle from the universal property suitable for proving statements about these definitions. We outline the steps needed to formalize the wedge product and $$\mathbb {N}$$
N
-grading, and some of the gaps in that currently make this challenging.
Schrödinger-improved Boussinesq system in two space dimensions
Authors: Ozawa Tohru , Tomioka Kenta
Published: April 2022

We study the Cauchy problem for the Schrödinger-improved Boussinesq system in a two-dimensional domain. Under natural assumptions on the data without smallness, we prove the existence and uniqueness of global strong solutions. Moreover, we consider the vanishing “improvement” limit of global solutions as the coefficient of the linear term of the highest order in the equation of ion sound waves tends to zero. Under the same smallness assumption on the data as in the Zakharov case, solutions in the vanishing “improvement” limit are shown to satisfy the Zakharov system.
Hodge ideals of free divisors
Authors: Castaño Domínguez Alberto , Narváez Macarro Luis , Sevenheck Christian
Published: April 2022

We consider the Hodge filtration on the sheaf of meromorphic functions along free divisors for which the logarithmic comparison theorem holds. We describe the Hodge filtration steps as submodules of the order filtration on a cyclic presentation in terms of a special factor of the Bernstein–Sato polynomial of the divisor and we conjecture a bound for the generating level of the Hodge filtration. Finally, we develop an algorithm to compute Hodge ideals of such divisors and we apply it to some examples.
Moderate shading did not affect barley yield in temperate silvoarable agroforestry systems
Authors: Vaccaro Christina , Six Johan , Schöb Christian
Published: April 2022

With climate change and an increasing global human population, the concept of agroforestry is gaining economic and environmental interest. The practice of growing trees and crops on the same land is mainly applied in (sub)tropical climate and rarer in temperate areas where farmers fear decreased understorey crop yields due to competition with trees. However, whether competition is stronger below- (soil moisture, nutrients) or aboveground (light) in a temperate silvoarable agroforestry system (AFS) is not clear. The effects of different treatments of light, water and nutrient availability on crop production in two temperate AFS in Central Switzerland were investigated, where summer barley (Hordeum vulgare L.) was grown as understorey crop under 90%, 40% and 0% shade nets, with and without irrigation and/or fertilisation in a fully factorial design. Yield was reduced by 26% under heavy shade; yield reductions under moderate shade were not significant. Fertilisation and irrigation increased crop yield by 13% and 6–9%, respectively, independent from shade. Individual seed mass was significantly increased by fertilisation from an average of 0.041 g (± 0.008 SD) in unfertilised treatments to an average of 0.048 g (± 0.010) in fertilised treatments. Fertilisation had the biggest impact on total seed number (p < 0.001) with on average 36 (± 26) seeds per individual in unfertilised plots and 61 (± 33) in fertilised plots. This study demonstrates that moderate shade (as can be expected in modern AFS) was not a major limiting factor for barley yield in these two AFS in Switzerland, indicating that AFS with appropriate management combined with suitable selection of understorey crops are an option for agricultural production in temperate regions without significant yield losses.
Multicriteria interpretability driven deep learning
Authors: Repetto Marco
Published: April 2022

Deep Learning methods are well-known for their abilities, but their interpretability keeps them out of high-stakes situations. This difficulty is addressed by recent model-agnostic methods that provide explanations after the training process. As a result, the current guidelines’ requirement for “interpretability from the start” is not met. As a result, such methods are only useful as a sanity check after the model has been trained. In an abstract scenario, “interpretability from the start” implies imposing a set of soft constraints on the model’s behavior by infusing knowledge and eliminating any biases. By inserting knowledge into the objective function, we present a Multicriteria technique that allows us to control the feature effects on the model’s output. To accommodate for more complex effects and local lack of information, we enhance the method by integrating particular knowledge functions. As a result, a Deep Learning training process that is both interpretable and compliant with modern legislation has been developed. Our technique develops performant yet robust models capable of overcoming biases resulting from data scarcity, according to a practical empirical example based on credit risk.
Investigation on dynamic characteristics of a rod fastening rotor-bearing coupling system with fixed-point rubbing
Authors: Yang Yang , Ouyang H. J. , Zeng Jin , Ma Hui , Yang Yiren , Cao Dengqing
Published: April 2022

The aim of this paper is to gain insight into the nonlinear vibration feature of a dynamic model of a gas turbine. First, a rod fastening rotor-bearing coupling model with fixed-point rubbing is proposed, where the fractal theory and the finite element method are utilized. For contact analysis, a novel contact force model is introduced in this paper. Meanwhile, the Coulomb model is adopted to expound the friction characteristics. Second, the governing equations of motion of the rotor system are numerically solved, and the nonlinear dynamic characteristics are analyzed in terms of the bifurcation diagram, Poincaré map, and time history. Third, the potential effects provided by contact degree of joint interface, distribution position, and amount of contact layer are discussed in detail. Finally, the contrast analysis between the integral rotor and the rod fastening rotor is conducted under the condition of fixed-point rubbing.
Brine shrimps adrift: historical species turnover in Western Mediterranean Artemia (Anostraca)
Authors: Sainz-Escudero Lucía , Karen López-Estrada E. , Rodríguez-Flores Paula C. , García-París Mario
Published: April 2022

Brine shrimps (Artemia) have undergone geographic range and demographic expansions as a result of their interaction with humans since the beginning of salt harvesting. This interaction has favoured the expansion of some species but compromising the survival of others. Mediterranean native populations of Artemia salina from coastal salterns and lagoons are facing the presence and expansion of the introduced and invasive American species Artemia monica (= A. franciscana). However, this species could not be the only threat. Parthenogenetic populations of the Asian species A. urmiana and A. sinica are widespread along the Mediterranean and other areas of the world. In this work, with the use of large cox1 and mitogenomic datasets, phylogenetic and phylogeographic inferences, and a time calibrated tree, we confirmed the Asian origin and recent arrival of the current Western Mediterranean parthenogenetic populations of Artemia. In addition, the replacement of Iberian populations of A. salina by Asiatic parthenogenetic populations lead us to recognize parthenogens as invasive. Current salterns development and commercial importance of Artemia make human-mediated introduction probable. These results demonstrate again the impact that changing human interests have on population expansion or decline of species adapted to anthropogenic habitats. Artemia salina decline makes urgent the implementation of conservation measures such as its use in fish farming and salt production or its inoculation in inland salterns.
Taurine Alleviates Chronic Social Defeat Stress-Induced Depression by Protecting Cortical Neurons from Dendritic Spine Loss
Authors: Zhu Yuanyuan , Wang Rui , Fan Ze , Luo Danlei , Cai Guohong , Li Xinyang , Han Jiao , Zhuo Lixia , Zhang Li , Zhang Haifeng , Li Yan , Wu Shengxi
Published: April 2022

Abnormal amino acid metabolism in neural cells is involved in the occurrence and development of major depressive disorder. Taurine is an important amino acid required for brain development. Here, microdialysis combined with metabonomic analysis revealed that the level of taurine in the extracellular fluid of the cerebral medial prefrontal cortex (mPFC) was significantly reduced in mice with chronic social defeat stress (CSDS)-induced depression. Therefore, taurine supplementation may be usable an intervention for depression. We found that taurine supplementation effectively rescued immobility time during a tail suspension assay and improved social avoidance behaviors in CSDS mice. Moreover, taurine treatment protected CSDS mice from impairments in dendritic complexity, spine density, and the proportions of different types of spines. The expression of N-methyl d-aspartate receptor subunit 2A, an important synaptic receptor, was largely restored in the mPFC of these mice after taurine supplementation. These results demonstrated that taurine exerted an antidepressive effect by protecting cortical neurons from dendritic spine loss and synaptic protein deficits.
Projected climate change and its impacts on glaciers and water resources in the headwaters of the Tarim River, NW China/Kyrgyzstan
Authors: Wortmann Michel , Duethmann Doris , Menz Christoph , Bolch Tobias , Huang Shaochun , Tong Jiang , Kundzewicz Zbigniew W. , Krysanova Valentina
Published: April 2022

Glacierised river catchments are highly sensitive to climate change, while large populations may depend on their water resources. The irrigation agriculture and the communities along the Tarim River, NW China, strongly depend on the discharge from the glacierised catchments surrounding the Taklamakan Desert. While recent increasing discharge has been beneficial for the agricultural sector, future runoff under climate change is uncertain. We assess three climate change scenarios by forcing two glacio-hydrological models with output of eight general circulation models. The models have different glaciological modelling approaches but were both calibrated to discharge and glacier mass balance observations. Projected changes in climate, glacier cover and river discharge are examined over the twenty-first century and generally point to warmer and wetter conditions. The model ensemble projects median temperature and precipitation increases of + 1.9–5.3 °C and + 9–24%, respectively, until the end of the century compared to the 1971–2000 reference period. Glacier area is projected to shrink by 15–73% (model medians, range over scenarios), depending on the catchment. River discharge is projected to first increase by about 20% in the Aksu River catchments with subsequent decreases of up to 20%. In contrast, discharge in the drier Hotan and Yarkant catchments is projected to increase by 15–60% towards the end of the century. The large uncertainties mainly relate to the climate model ensemble and the limited observations to constrain the glacio-hydrological models. Sustainable water resource management will be key to avert the risks associated with the projected changes and their uncertainties.
Global implicit solver for multiphase multicomponent flow in porous media with multiple gas components and general reactions
Authors: Knodel Markus M. , Kräutle Serge , Knabner Peter
Published: April 2022

In order to study the efficiency of the various forms of trapping including mineral trapping scenarios for CO2 storage behavior in deep layers of porous media, highly nonlinear coupled diffusion-advection-reaction partial differential equations (PDEs) including kinetic and equilibrium reactions modeling the miscible multiphase multicomponent flow have to be solved. We apply the globally fully implicit PDE reduction method (PRM) developed 2007 by Kräutle and Knabner for one-phase flow, which was extended 2019 to the case of two-phase flow with a pure gas in the study of Brunner and Knabner. We extend the method to the case of an arbitrary number of gases in gaseous phase, because CO2 is not the only gas that threats the climate, and usually is accompanied by other climate killing gases. The application of the PRM leads to an equation system consisting of PDEs, ordinary differential equations, and algebraic equations. The Finite Element discretized / Finite Volume stabilized equations are separated into a local and a global system but nevertheless coupled by the resolution function and evaluated with the aid of a nested Newton solver, so our solver is fully global implicit. For the phase disappearance, we use persistent variables which lead to a semismooth formulation that is solved with a semismooth Newton method. We present scenarios of the injection of a mixture of various gases into deep layers, we investigate phase change effects in the context of various gases, and study the mineral trapping effects of the storage technique. The technical framework also applies to other fields such as nuclear waste storage or oil recovery.
Is there an optimum of realism in computer-generated instructional visualizations?
Authors: Skulmowski Alexander
Published: April 2022

Realistic visualizations are abundantly used in digital education. However, the use of realism is still thought to risk a cognitive overload due to excessive details. Moreover, it is still not precisely known whether there is an optimal level of realism that benefits learners the most. In two experimental studies, different versions of anatomical visualizations were compared regarding their effects on retention performance and the subjective cognitive load experienced during learning. In Experiment 1 (n = 73), four visualizations with minor variations in the geometry and shading of the model featured in the visualizations were used. Although neither the level of detail in the geometry nor the realism of the shading resulted in significant differences, a detailed model with simplified shading elicited the highest retention scores descriptively. In Experiment 2 (n = 156), a schematic visualization was compared with an “idealized” model featuring only simplified shading and a highly realistic rendering. There most realistic version elicited the highest retention scores, but also the highest cognitive load ratings. Taken together, the results suggest that the optimal level of realism might lie on the more realistic end of the spectrum for learning tasks focused on the memorization of shapes that are assessed using image-based tests.
The webcam and student engagement in synchronous online learning: visually or verbally?
Authors: Händel Marion , Bedenlier Svenja , Kopp Bärbel , Gläser-Zikuda Michaela , Kammerl Rudolf , Ziegler Albert
Published: April 2022

Given that video conferencing serves as a crucial means for remote teaching, the current study investigated higher education students’ (non)use of webcams and engagement in synchronous online courses. Three phases were studied: (1) A state of engagement; (2) antecedents that influence it; and (3) consequences of engagement. The cross-sectional online survey encompassed 3,610 students. Results indicated that visual and verbal engagement were only slightly related to each other. Structural equation modelling revealed different direct and indirect influences on either visual or verbal engagement in synchronous online higher education courses. Due to the novelty of the research scope, results of this study provide a foundation for further investigation.
Prevalence of acute respiratory infections among children in India: Regional inequalities and risk factors
Authors: Hasan Md Masud , Saha Kamal Kumar , Yunus Rossita Mohamad , Alam Khorshed
Published: April 2022

Aim

The high incidence of acute respiratory infection (ARI)-related morbidity and mortality is a major public health concern in developing countries. This study aimed to quantify regional inequalities and the degree of association between childhood ARI and background factors.

Methods

This study utilised information of 238 945 children aged below five years extracted from the Fourth Indian National Family Health Survey conducted in 2015–16. Inter-state and regional inequality in the prevalence of ARI were quantified and presented using a map of India and forest plot. The association of background characteristics and ARI was quantified using bivariate and multivariable binary logistic regression models.

Results

Significant inequalities in the prevalence of childhood ARI were observed across the six regions of India. Considering the children from north-east region as a reference, those from north, central and east regions were 0.68, 1.02 and 0.57 times more likely to suffer from ARI. Comorbidity, sex, age and nutritional status of children were significantly associated with the prevalence of ARI.

Conclusions

ARI remains a significant public health concern among Indian children. The results of this study showed that significant regional disparities in the prevalence of ARI exist in India. This study adds value to the better understanding of inequality patterns and quantifies within- and intra-region inequalities in the prevalence of ARI in India.
CO2 supplementation eliminates sugar-rich media requirement for plant propagation using a simple inexpensive temporary immersion photobioreactor
Authors: Trauger Marena , Hile April , Sreenivas Krishnan , Shouse Eva Mei , Bhatt Jishnu , Lai Tina , Mohandass Ramya , Tripathi Leena , Ogden Aaron J. , Curtis Wayne R.
Published: April 2022

In vitro plant propagation systems such as temporary immersion bioreactors (TIBs) are valuable tools that enable production of disease-free plants with improved traits. However, TIB systems can be expensive, difficult to implement, and prone to contamination due to sugar rich propagation media. Using rapidly growing chicory root cultures to expedite design-build-test cycles, we report here an improved, low-cost version of a previously reported Hydrostatically-driven TIB (Hy-TIB) that facilitates economical use of gas mixtures. Bioreactor improvements include decreased material costs, expanded modes of operation, and a horizontal orientation of a plastic film plant growth chambers that increase propagule light exposure. To take advantage of these improvements, we describe here experiments that evaluate the impacts of elevated CO2 on propagation of cacao (Theobroma cacao) secondary embryos and nodal cultures of yam (Dioscorea spp.) during both phototrophic and photomixotrophic growth. Our experiments show that elevated CO2 during plant propagation significantly improved both cacao and yam propagule development and eliminated the need for supplemental sugars in tissue culture growth media. Thus, our improved Hy-TIB shows potential as a simple, low-cost, and scalable propagation platform with cost-effective gas composition control and reduced risk of contamination overgrowth. We provide detailed instructions for assembly of this Hy-TIB design and discuss the implications of its adoption in food-insecure regions of the world.
Biopolymer-biocement composite treatment for stabilisation of soil against both current and wave erosion
Authors: Dubey Anant Aishwarya , Hooper-Lewis Jack , Ravi K. , Dhami Navdeep Kaur , Mukherjee Abhijit
Published: April 2022

Increased frequency of extreme weather events has made the conservation of riverbanks and coastlines a global concern. Soil stabilisation via microbially induced calcite precipitation (MICP) is one of the most eco-suitable candidates for improving resilience against erosion. In this study, the erosion characteristics of soil treated with various levels of biocementation are investigated. The samples were subjected to hydraulic flow in both tangential and perpendicular directions in a flume to simulate riverbank and coastal situations. Soil mass loss, eroded volume, and cumulative erosion rates of the treated soil against the applied hydraulic energy density have been reported. Post erosion exposure, the residual soil has been assessed for its properties using needle penetration resistance, precipitated calcium carbonate content and microstructure. It was observed that soil erosion declined exponentially with the increase in calcium carbonate content against the perpendicular waves. However, biocementation leads to brittle fracture beyond a threshold, limiting its efficacy, especially against the tangential waves. Additional composite treatment with a biopolymer was found to improve the resilience of the soil specimens against erosion. The composite treatment required half of the quantity of the biocementing reagents in comparison to the equally erosion-resistant plain biocemented sample. Therefore, stoichiometrically the composite treatment is likely to yield 50% lesser ammonia than plain biocement treatment. This investigation unravels a promising soil conservation technique via the composite effect of biocement and biopolymer.
Preface
Authors: Ahmedov Bobomurat J. , Bokhari Ashfaque H.
Published: April 2022

This special issue of the Arabian Journal of Mathematics consists of research articles on some interesting topics in Theoretical & Mathematical Physics as well as theoretical aspects of Relativistic Astrophysics. These research articles were presented in an International Conference on Relativistic Astrophysics and Gravitation (ICRAG) held in Ulugh Beg Astronomical Institute of Uzbekistan during May 12–14, 2021.
Gyro-stellar inertial attitude estimation for satellite with high motion rate
Authors: Lin C.-L. , Li J.-C. , Chiu C.-L. , Wu Y.-W.A. , Jan Y.-W.
Published: April 2022

For a common micro-satellite, orbiting in a circular sun-synchronous orbit (SSO) at an altitude between 500 and 600km, the satellite attitude during off-nadir imaging and staring-imaging operations can be up to ±45 degree on roll and pitch angles. During these off-nadir pointing for both multi-trip operation and staring imaging operations, the spacecraft body is commonly subject to high-rate motion. This posts challenges for a spacecraft attitude determination subsystem called Gyro Stellar Inertial Attitude Estimate (GS IAE), which employs gyros and star sensors to maintain the required attitude knowledge, since star trackers will severely degrade attitude estimation accuracies when the spacecraft is subject to high-rate motion. This paper analyses the star motion-induced errors for a typical star tracker, models the star motion-induced errors to assess the performance impact on the attitude estimation accuracy, and investigates the adaptive extended Kalman filter design in the GS IAE while evaluating its effectiveness.
Bowen–Walters expansiveness for semigroups of linear operators
Authors: LEE J. , MORALES C. A.
Published: April 2022

We define positively expansive semigroups of linear operators on Banach spaces. We characterize these semigroups in terms of the point spectrum of the infinitesimal generator. In particular, we prove that a positively expansive semigroup is neither uniformly bounded nor equicontinuous. We apply our results to the Lasota equation.
Healthcare worker safety program in a coronavirus disease 2019 (COVID-19) alternate care site: The Javits New York Medical Station experience
Authors: Thompson Chad N. , Mugford Christopher , Merriman Joel R. , Chen Mark A. , Hutter Joseph D. , Maruna Thomas J. , Bacon Wanza R. , Childs Richard W. , Pati Rituparna , Clifton G. Travis , Pazdan Renee M.
Published: April 2022

Objective:

In March 2020, New York City became the epicenter of the coronavirus disease 2019 (COVID-19) pandemic in the United States. Because healthcare facilities were overwhelmed with patients, the Jacob K. Javits Convention Center was transformed into the nation’s largest alternate care site: Javits New York Medical Station (hereafter termed Javits). Protecting healthcare workers (HCWs) during a global shortage of personal protective equipment (PPE) in a nontraditional healthcare setting posed unique challenges. We describe components of the HCW safety program implemented at Javits.

Setting:

Javits, a large convention center transformed into a field hospital, with clinical staff from the US Public Health Service Commissioned Corps and the US Department of Defense.

Methods:

Key strategies to ensure HCW safety included ensuring 1-way flow of traffic on and off the patient floor, developing a matrix detailing PPE required for each work activity and location, PPE extended use and reuse protocols, personnel training, and monitoring adherence to PPE donning/doffing protocols when entering or exiting the patient floor. Javits staff who reported COVID-19 symptoms were immediately isolated, monitored, and offered a severe acute respiratory coronavirus virus 2 (SARS-CoV-2) reverse-transcriptase polymerase chain reaction (RT-PCR) test.

Conclusions:

A well-designed and implemented HCW safety plan can minimize the risk of SARS-CoV-2 infection for HCWs. The lessons learned from operating the nation’s largest COVID-19 alternate care site can be adapted to other environments during public health emergencies.