bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fecal Fungi Dysbiosis in Nonalcoholic Fatty Liver Disease
Authors: You Ningning , Xu Jiali , Wang Liyan , Zhuo Lili , Zhou Jingxin , Song Yu , Ali Aliaweis , Luo Yan , Yang Jin , Yang Wenjun , Zheng Minghua , Xu Jing , Shao Li , Shi Junping 
Published: January 2021

ObjectiveNonalcoholic fatty liver disease (NAFLD) can systematically harm more aspects of human health than just the liver. In addition to the potential roles of the gut microbiota in NAFLD, commensal fungi can functionally replace intestinal bacteria in maintaining the host immune response in the gut by reversing disease susceptibility. Therefore, gut commensal fungi should be studied to help understand NAFLD.MethodsThe fungal compositions of 79 patients with NAFLD and 34 matched healthy subjects were studied via internal transcribed spacer sequencing. In the NAFLD group, 32 patients underwent liver biopsies to evaluate the associations between gut fungi and NAFLD development.ResultsThe fungal microbiota distribution was skewed in the patients with NAFLD. The relative abundances of Talaromyces, Paraphaeosphaeria, Lycoperdon, Curvularia, Phialemoniopsis, Paraboeremia, Sarcinomyces, Cladophialophora, and Sordaria were higher in patients with NAFLD, whereas the abundances of Leptosphaeria, Pseudopithomyces, and Fusicolla were decreased. Patients with NAFLD exhibited more co‐occurring fungal intrakingdom correlations. Several fungi were found to be associated with liver injury, lipid metabolism, and the development of NAFLD.ConclusionsThis study found that gut fungi may play some roles in NAFLD development. Research on gut fungi may be of great value in diagnosing and monitoring NAFLD.
Influence of Nanoparticle Processing on the Thermoelectric Properties of (BixSb1−X)2Te3 Ternary Alloys
Authors: Salloum Sarah , Bendt Georg , Heidelmann Markus , Loza Kateryna , Bayesteh Samaneh , Sepideh Izadi M. , Kawulok Patrick , He Ran , Schlörb Heike , Perez Nicolas , Reith Heiko , Nielsch Kornelius , Schierning Gabi , Schulz Stephan 
Published: January 2021

AbstractThe synthesis of phase‐pure ternary solutions of tetradymite‐type materials (BixSb1−x)2Te3 (x=0.25; 0.50; 0.75) in an ionic liquid approach has been carried out. The nanoparticles are characterized by means of energy‐dispersive X‐ray spectroscopy (EDX), powder X‐ray diffraction (PXRD), scanning electron microscopy (SEM), and transmission electron microscopy. In addition, the role of different processing approaches on the thermoelectric properties ‐ Seebeck coefficient as well as electrical and thermal conductivity ‐ is demonstrated.
Reactivity and Controlled Redox Reactions of Salt‐like Intermetallic Compounds in Imidazolium‐Based Ionic Liquids
Authors: Feng Xian‐Juan , Lerch Swantje , Biller Harry , Micksch Maik , Schmidt Marcus , Baitinger Michael , Strassner Thomas , Grin Yuri , Böhme Bodo 
Published: January 2021

AbstractSubstituted imidazolium ionic liquids (ILs) were investigated for their reactivity towards Na12Ge17 as a model system containing redox‐sensitive Zintl cluster anions. The ILs proved widely inert for imidazolium cations with a 1,2,3‐trisubstitution at least by alkyl groups, and for the anion bis(trifluoromethylsulfonyl)azanide (TFSI). A minute conversion of Na12Ge17 observed on long‐time contact with such ILs was not caused by dissolution of the salt‐like compound, and did thus not provide dissolved Ge clusters. Rather, a cation exchange led to the transfer of Na+ ions into solution. In contrast, by using benzophenone as an oxidizer, heterogeneous redox reactions of Na12Ge17 were initiated, transferring a considerable part of Na+ into solution. At optimized conditions, an X‐ray amorphous product NaGe6.25 was obtained, which was thermally convertible to the crystalline type‐II clathrate Na24–δGe136 with almost completely Na‐filled polyhedral cages, and α‐Ge. The presented method thus provides unexpected access to Na24–δGe136 in bulk quantities.
A Low‐Cost and Scalable Carbon Coated SiO‐Based Anode Material for Lithium‐Ion Batteries
Authors: Huang Zhihao , Dang Guoju , Jiang Wenping , Sun Yuanyu , Yu Meng , Zhang Quansheng , Xie Jingying 
Published: January 2021

AbstractSilicon monoxide (SiO) is considered as one of the most promising alternative anode materials thanks to its high theoretical capacity, satisfying operating voltage and low cost. However, huge volume change, poor electrical conductivity, and poor cycle performance of SiO dramatically hindered its commercial application. In this work, we report an affordable and simple way for manufacturing carbon‐coated SiO−C composites with good electrochemical performance on kilogram scales. Industrial grade SiO was modified by carbon coating using cheap and environment friendly polyvinyl pyrrolidone (PVP) as carbon source. High‐resolution transmission electron microscopy (HRTEM) and Raman spectra results show that there is an amorphous carbon coating layer with a thickness of about 40 nm on the surface of SiO. The synthesized SiO−C‐650 composite shows great electrochemical performance with a high capacity of 1491 mAh.g−1 at 0.1 C rate and outstanding capacity retention of 67.2 % after 100 cycles. The material also displays an excellent performance with a capacity of 1100 mAh.g−1 at 0.5 C rate. Electrochemical impedance spectroscopy (EIS) results also prove that the carbon coating layer can effectively improve the conductivity of the composite and thus enhance the cycling stability of SiO electrode.
Optimal design of unit‐cell based programmable materials
Authors: Lichti Tobias , Andrä Heiko , Leichner Alexander , Müller Ralf , Wenz Franziska 
Published: January 2021

AbstractAn optimal design for a programmable material based on an array of unit‐cells is established. A programmable material behavior is achieved by using unit‐cells with complex and adjustable features arising from the inner structure of each cell. This type of materials has the potential of replacing the functionality of entire systems consisting of sensors and actuators, provided that an optimal inner structure is given. In this paper the multiscale optimization problem and a solution strategy are presented. An efficient data driven method is used for the solution of the macroscopic boundary value problem. Finally, an example of an optimized parameter distribution for a unit‐cell based material is shown.
Quantized Compressed Sensing by Rectified Linear Units
Authors: Jung Hans Christian , Maly Johannes , Palzer Lars , Stollenwerk Alexander 
Published: January 2021

AbstractThis work is concerned with the problem of recovering high‐dimensional signals, which belong to a convex set of low‐complexity, from a small number of quantized measurements. We propose to estimate the signals via a convex program based on rectified linear units (ReLUs) for two different quantization schemes, namely one‐bit and uniform multi‐bit quantization. Assuming that the linear measurement process can be modelled by a sensing matrix with i.i.d. subgaussian rows, we obtain for both schemes near‐optimal uniform reconstruction guarantees by adding well‐designed noise to the linear measurements prior to the quantization step. In the one‐bit case, we show that the program is robust against adversarial bit corruptions as well as additive noise on the linear measurements. Further, our analysis quantifies precisely how the rate‐distortion relationship of the program changes depending on whether we seek reconstruction accuracies above or below the noise floor. The proofs rely on recent results by Dirksen and Mendelson on non‐Gaussian hyperplane tessellations.
Numerical Analysis for an Electro‐Magneto‐Mechanical Phenomenon with High‐Order Accurate Methods
Authors: Gleim Tobias , Chen Hefeng 
Published: January 2021

AbstractThis paper establishes an axisymmetric model for a levitation device. Therein, the Maxwell equations are combined with the balance of linear momentum. Different possible formulations to describe the MAXWELL equations are presented and compared and discussed in the example. A high order finite element discretization using GALERKIN's method in space and the generalized NEWMARK‐α method in time are developed for the electro‐magneto‐mechanical approach. Several studies on spatial and temporal discretization with respect to convergence will be investigated. In addition, the boundary influences and the domain size with respect to the levitation device are also examined.
A displacement‐based analytical stress solution for various adhesive joint configurations
Authors: Methfessel Thomas S. , Becker Wilfried 
Published: January 2021

AbstractThe present work provides a simple and precise thermo‐mechanical model for the prediction of stress distributions in adhesive joints. A displacement‐based derivation is applied, using a general sandwich‐type model for the overlap region. For the adhesive layer a linear displacement approach is proposed, which captures the variation of the shear stresses in the through‐thickness direction. The model covers various joint configurations with linear‐elastic material behavior under different load cases.
A localized meshless collocation method based on semi‐analytical basis functions for bandgap calculation of elastic waves in phononic crystals
Authors: Fu Zhuo-Jia , Li Lufeng , Gu Yan 
Published: January 2021

AbstractThis paper makes the first attempt to develop an efficient localized meshless collocation method (LMCM) based on the semi‐analytical T‐complete functions to calculate the bandgaps of elastic waves in solid phononic crystals. In comparison with the FEM (COMSOL software), the proposed LMCM can provide the similar accurate results with less computational resources for band structure calculation.
Nonnegative Matrix Factorization models for knowledge extraction from biomedical and other real world data
Authors: Esposito Flavia , Del Buono Nicoletta , Selicato Laura 
Published: January 2021

AbstractInspect data for searching valuable information hidden in represents a key aspect in several fields. Fortunately, most of the available data presents an embedded mathematical structure which can be profitably exploited to better investigate latent patterns hidden in them.Dimensionality Reduction (DR) approaches represent one of the most suitable instrument to untangle latent information. These techniques aim to represent data under analysis onto a low‐dimensional space allowing to consider most of all of intrinsic knowledge as ideal sources (namely basis) of the process under consideration.In this work we consider Nonnegative Matrix Factorizations (NMFs), which prove to be the most effective among DR approaches in analyzing real‐life nonnegative data.NMF simulates the human part‐based learning process which states that parts are combined additively to form a whole. Some variants of NMF will be also presented as minimization tasks to which regularization terms can be added in accordance to some additional characteristics (such as sparsity or orthogonality).We investigate significant computational and interpretative aspects related to NMF according to different application domains, with a specific attention to the analysis of biological data. Moreover we present a new NMF model designed for microarray data analysis that incorporates specific biological proprieties as different constraints. Since NMF and its variants are daily used in several application domains, we conclude stressing how NMF and its constrained variants work in some real life applications, showing some original works related to the analysis of data from engineering field.
Modeling and Simulation of the Thermo‐Mechanically Induced Fracture Behavior of an Epoxy System in Electric Traction Machines
Authors: Böckenhoff Paul , Kästner Markus 
Published: January 2021

AbstractThis papier studies the critical stress state prediction for production‐ and operation‐induced loads on an epoxy‐based mold in an electric rotor. The constitutive behavior of the mold is given by a linear thermo‐viscoelastic material model with an ARRHENIUS‐based time‐temperature superposition, which is modified to also account for chemical curing shrinkage. A finite element analysis (FEA) is performed to evaluate two loading states which result in mold failure due to cracking. The results are compared to experimental evidence. The method is found to predict the location of crack initiation, as well as the direction of crack propagation.
Non‐linear structural membranes and ropes based on Tangential Differential Calculus
Authors: Fries Thomas-Peter , Schöllhammer Daniel 
Published: January 2021

AbstractThe finite strain theory for ropes and membranes is reformulated in the frame of the Tangential Differential Calculus (TDC) resulting in a unification in a geometrical, mechanical, and numerical sense. The resulting formulation applies to parametric and implicit geometry definitions of ropes and membranes. In contrast to classical theories, the formulation is suitable not only to the Surface FEM but also to recent Trace and Cut FEMs.
Reduced order voxel‐based model for computational modelling of highly compressible composite materials
Authors: Iskhakov Tagir , Timothy Jithender J. , Bessa Miguel , Meschke Günther 
Published: January 2021

AbstractCompressible cementitious materials are used in tunnel lining systems deployed in ground conditions characterised by expansive soils. The deformation capacity of a cementitious material can be enhanced by the introduction of weak inclusions (EPS) and/or pores. The overall behaviour of such porous cementitious composite materials is strongly influenced by the material properties of the individual components (EPS, pores, sand particles, aggregates), the geometry of the constituents, their spatial distribution and volume. The compaction behaviour of such composites can be described by a voxel model with a discrete distribution of material properties, where the voxels are compacted by applying an eigenforce. The proposed model is integrated into the framework of the reduced order self‐consistent clustering strategy at the scale of a Representative Elementary Volume [1]. The accuracy of the reduced order strategy combined with the voxel model is analysed by comparing it to the full voxel compaction model
An Active Female Human Body Model for Simulation of Rear‐End Impact Scenarios
Authors: Kempter Fabian , Kleinbach Christian , Staudenmeyer Martin , Fehr Jörg 
Published: January 2021

AbstractWhiplash associated disorder (WAD) is a type of injury caused by rear‐end impacts. It is a painful long‐term injury of the soft tissue in the neck, which women suffer from 1.5 to 3 times more often compared to men. Progress in WAD research is difficult, as (i) it occurs at a loading level where muscle activity can no longer be neglected, (ii) as soft tissue characteristics play an essential role in WAD and (iii) there is no consensus on the injury mechanism causing WAD. Therefore, computational models of the human body are the most promising method to advance the understanding of WAD. Here, improvements of boundary and initial conditions are presented together with a discussion of its effects on the head kinematics and neck load.
A simulation of an electric machine considering the coupling of rotor‐ and electrodynamics
Authors: Koch Sebastian , Duvigneau Fabian , Woschke Elmar 
Published: January 2021

AbstractIn this paper, a method is presented to determine the vibrational behavior of an electric motor and the associated structure. Therefore, a holistic simulation approach is used, which takes into account the mutual influence of structural mechanics and electrodynamics. For this purpose, a multi body simulation (MBS) is extended so that electromagnetic loads can be considered, which are calculated by using the finite element method (FEM). In electric machines an undisturbed and constant magnetic field is of great importance. Even small variations of the air gap lead to changes in the magnetic field compared to the ideal geometry, which cause a change in the resulting torque and vibration excitation. Especially local and global asymmetric air gap changes due to load‐ and operation‐dependent deformations of the stator and rotor are problematic. Such deformations result on the one hand from the electromagnetically excited structural vibrations and on the other hand from the rotordynamic loads. For these reasons, it is necessary to consider the electro‐ and structural‐dynamic effects together. The developed method is presented on a simple generic motor to show the influence of the coupling.
The Difference between Optimal Rank‐1 Hankel Approximations in the Frobenius Norm and the Spectral Norm
Authors: Knirsch Hanna , Petz Markus , Plonka Gerlind 
Published: January 2021

AbstractWe present new examples illustrating the fact that optimal Hankel structured rank‐1 approximation of matrices is usually different for the Frobenius and spectral norm. Further, we compare our results for optimal rank‐1 Hankel approximation to the results of the well‐known Cadzow algorithm [3].
Damage modelling for the lifetime prediction of structural adhesive joints subjected to hygro‐thermo‐mechanical long‐term loading
Authors: Kroll Ulrich , Matzenmiller Anton 
Published: January 2021

AbstractA damage model is presented for the lifetime prediction of structural adhesive joints under hygro‐thermo‐mechanical loading. The damage approach is applied through a cohesive zone model together with the concept of effective stress. It consists of a temperature‐dependent creep and hygro damage evolution due to mechanical loading and chemical aging, caused by the local water concentration. The creep damage part considers multiaxiality of the loading by an equivalent stress. The model parameters are identified by means of rupture times from creep tests under different mechanical loadings, temperatures and humidity conditions. The model and the identified parameters are verified by means of FE‐simulations until rupture of an adhesive joint.
Spatial motion of a pendulum in a jet flow: qualitative aspects and integrability
Authors: Shamolin Maxim V. 
Published: January 2021

AbstractThe presented work is devoted to the problem of motion in a resisting medium of a rigid body whose surface of contact with the medium is only a plane part of its exterior surface. In this case, the force field is constructed from the reasons for the medium action on the body under the streamline (or separation) flow around and quasi‐stationarity conditions. It turns out that studying the motion of such a class of bodies reduces to systems with energy scattering (dissipative systems) or with its pumping (the so‐called anti‐dissipative systems) [1,2]. Note that similar problems were already appeared in applied aerodynamics in the studies of Central Aero‐Hydrodynamic Institute named after professor N. E. Zhukovskii.
Numerical analysis of wave mixing in 3‐D infinite elastic solids with a spherical damage
Authors: Ankay Benjamin , Zhang Chuanzeng 
Published: January 2021

AbstractIn this paper the 3‐D wave propagation in an infinite elastic solid with a spherical damage is numerically simulated by a mapped staggered Chebyshev pseudo‐spectral collocation method. In the numerical simulation process, the so‐called Convolutional‐Perfectly‐Matched‐Layers (CPML) are used to model the absorbing boundaries and the wave excitations are specified inside the corresponding physical domain. Furthermore, to consider different damage models the classical nonlinear elastic and non‐classical hysteretic material laws are used. The main objective of this study is to evaluate the influences of the particular wave modes and the mixing of the incident waves on the generated nonlinear scattered wave field. To analyze the specific scattered wave fields around the spherical damage region the computed time‐domain signals are transformed to the frequency‐domain.
Derivation of Analytical, Closed‐form Formulas for the Calculations of Instantaneous Screw Axes of Arbitrary Rigid 3D Multi‐Body Systems
Authors: Boungard Jonas , Wackerfuß Jens 
Published: January 2021

AbstractA method to calculate the parameters for each instantaneous and relative instantaneous screw axis in an arbitrary rigid multi‐body system is presented. At first a kinematic analysis is performed which calculates the displacements of all nodes and the rotation of each body. In the next step the displacements of the nodes and the rotation of the bodies are used to calculate the instantaneous screw axis of each body. With the information on the instantaneous screw axes the instantaneous relative screw axes can be computed too. An example of the calculation and the visualization of the instantaneous screw axes is given.
Numerical study of shear bands formation in a 3D‐printed Zr‐based bulk metallic glass under uniaxial loading
Authors: Shi Jianye , Ma Songyun , Markert Bernd 
Published: January 2021

AbstractProcessing metallic materials via selective laser melting (SLM) enables the production of bulk metallic glasses (BMGs) with large size and complex shape, which is difficult or even impossible to achieve using traditional manufacturing techniques. In this study, the initiation and propagation of shear bands as well as the tensile strength in a 3D‐printed BMG with printing defects by means of inherent porosities are studied. A multi‐slips system model based on Mohr‐Coulomb theory is applied.
Machine Learning with Feature Importance Analysis for Tornado Prediction from Environmental Sounding Data
Authors: Coffer Brice , Kubacki Michaela , Wen Yixin , Zhang Ting , Barajas Carlos A. , Gobbert Matthias K. 
Published: January 2021

AbstractTornadoes pose a forecast challenge to National Weather Service forecasters because of their quick development and potential for life‐threatening damage. The use of machine learning in severe weather forecasting has recently garnered interest, with current efforts mainly utilizing ground weather radar observations. In this study, we investigate machine learning techniques to discriminate between nontornadic and tornadic storms solely relying on the Rapid Update Cycle (RUC) sounding data that represent the pre‐storm atmospheric conditions. This approach aims to provide for early warnings of tornadic storms, before they form and are detectable by weather radar observations. Feature analysis of a Random Forest machine learning model uncovers that the pressure variable has little impact on the classification process, which is consistent with known key physical attributes of tornado formation, demonstrating the ability of machine learning techniques to provide insight solely based on the data.
Phase field modeling and simulation of the evolution of twelve crystallographic martensite variants in austenitic parent grains
Authors: Graf Marius , Kuntz Matthias , Autenrieth Hermann , Diewald Felix , Müller Ralf 
Published: January 2021

AbstractImportant criteria for the design of dynamically loaded components are strongly influenced by the microstructural properties. Motivated by this, models were developed which can predict the lifetime of components based on the microstructure. With regard to steel materials, the martensitic microstructure is of great importance. The subject of current research is therefore to work on simulation models that can predict the morphology of the microstructure depending on the process parameters during production. In this context a phase‐field model, which considers twelve crystallographic martensite variants corresponding to the Nishiyama‐Wassermann orientation relationship, is presented. The order parameters are used to interpolate between the initial (austenite) and final (martensite) state. With this model, the evolution of a thermal induced martensitic microstructure is simulated. In order to define the displasive characteristics of the martensite variants, the well‐known phenomenological theory of martensite crystallography is deployed. Simulations using the finite element method in the small strain context show the applicability of the model. A qualitative comparison of the simulated microstructures with experimental data is carried out.