bluuebunny/crossref_metadata_2025 huggingface dataset:
Linked disturbance in the temperate forest: Earthworms, deer, and canopy gaps
Authors: Reed Samuel P. , Bronson Dustin R. , Forrester Jodi A. , Prudent Leah M. , Yang Anna M. , Yantes Austin M. , Reich Peter B. , Frelich Lee E.
Published: March 2023

Despite the large body of theory concerning multiple disturbances, relatively few attempts have been made to test the theoretical assumptions of how and if disturbances interact. Of particular importance is whether disturbance events are linked, as this can influence the probability and intensity of ecological change. Disturbances are linked when one disturbance event increases or decreases the likelihood or extent of another. To this end, we used two long‐term, multi‐disturbance experiments in northern Wisconsin to determine whether earthworm invasion is linked to canopy gap creation and white‐tailed deer browsing. These three disturbances are common and influential within North American temperate forests, making any interactions among them particularly important to understand. We expected both deer and canopy gaps to favor invasive earthworms, particularly species that live close to or on the soil surface. However, we found only partial support of our hypotheses, as both deer exclosures and canopy gaps decreased earthworms in each experiment. Further, earthworm density increased the most over time in areas far from the gap center and in areas with deer present. Deer exclosures primarily decreased Aporrectodea and Lumbricus species, while gaps decreased Dendrobaena and Lumbricus species. Our findings show that earthworm invasion is linked to deer presence and gap‐creating disturbances, which provides new insight in multiple disturbance theory, aboveground–belowground dynamics, and temperate forest management.
Immunomodulation of neutrophil granulocyte functions by bacterial polyphosphates
Authors: Krenzlin Viola , Schöche Johannes , Walachowski Sarah , Reinhardt Christoph , Radsak Markus P. , Bosmann Markus
Published: March 2023

Polyphosphates are highly conserved, linear polymers of monophosphates that reside in all living cells. Bacteria produce long chains containing hundreds to thousands of phosphate units, which can interfere with host defense to infection. Here, we report that intratracheal long‐chain polyphosphate administration to C57BL/6J mice resulted in the release of proinflammatory cytokines and influx of Ly6G+ polymorphonuclear neutrophils in the bronchoalveolar lavage fluid causing a disruption of the physiologic endothelial–epithelial small airway barrier and histologic signs of lung injury. Polyphosphate‐induced effects were attenuated after neutrophil depletion in mice. In isolated murine neutrophils, long‐chain polyphosphates modulated cytokine release induced by lipopolysaccharides (LPS) from Gram‐negative bacteria or lipoteichoic acid from Gram‐positive bacteria. In addition, long‐chain polyphosphates induced immune evasive effects in human neutrophils. In detail, long‐chain polyphosphates downregulated CD11b and curtailed the phagocytosis of Escherichia coli particles by neutrophils. Polyphosphates modulated the migration capacity by inducing CD62L shedding resulting in CD62Llow and CD11blow neutrophils. The release of IL‐8 induced by LPS was also significantly reduced. Pharmacologic blockade of PI3K with wortmannin antagonized long‐chain polyphosphate‐induced effects on LPS‐induced IL‐8 release.

In conclusion, polyphosphates govern immunomodulation in murine and human neutrophils, suggesting polyphosphates as a therapeutic target for bacterial infections to restore innate immune defense.
The effect of propylene glycol addition on the flavour compounds retention of peppermint powders
Authors: Chun Cui , Mingqi Gao , Xuewei Jia , Bingjie Ma , Tianxiao Li , Shu Tian , Chunping Xu
Published: March 2023

Compared with peppermint oil, natural peppermint has more ingredients, a layered fragrance, and a green colour. It has been widely used as a nutritional additive, herbal tea, food flavouring or colouring. In this work, the retention of volatile flavour compounds of peppermint powders was enhanced by propylene glycol, a reagent that enhances hydrogen bonds and moisture absorption. The levels of influence of propylene glycol content on the retention of different volatile flavour compounds, moisture absorption and water distribution were evaluated by GC–MS, dynamic water absorption instrument (DVS), and low‐field nuclear magnetic resonance (LF‐NMR), respectively. GC–MS analysis showed that the volatile substances of peppermint powders (PMs) without propylene glycol were reduced to 22 kinds after storage for 90 days, and the total amount of volatile substances remained at 40.94%; PG2 with 2% propylene glycol had the best flavour retention. After 90 days of storage, the residual percentage of volatile flavour compounds of PG2 was approximately 72.56%, which was significantly increased compared with that of PM. The DVS results suggested that all the peppermint powders adopted a type III moisture absorption isotherm, and they all had multilayer adsorbed water. PG2 had the best moisture retention capacity and the highest hygroscopic hysteresis, while PG4 with a high propylene glycol content had a relatively poor moisture retention capacity. Similarly, LF‐NMR analysis showed that PG2 had a higher proportion of bound water and lower relaxation times T21 and T22 under different humidity conditions, indicating that it had the strongest water binding capacity. The correlation analysis showed that there was a significant positive correlation between the residual volatile compounds of peppermint powders and the peak area of bound water A21. The higher the proportion of strongly bound water in peppermint particles was, the more residual volatile substances were identified in peppermint particles. These results show that peppermint particles supplemented with propylene glycol can significantly improve the flavour retention ability of peppermint powders. In short, the results could be applied to the storage stability and quality control of peppermint products.
Thermal performance of dynamic, origami‐inspired geometries: An experimental study
Authors: Ahmed Farhan , Khatamifar Mehdi , Lin Wenxian , Situ Rong
Published: March 2023

Origami has become an increasingly popular geometry in thermal engineering, namely, heat regulatory applications such as heat sinks and radiators. In this study, the radiative heating and radiative and natural convective cooling of three origami geometries (W‐fold, Miura Ori (1), and Miura Ori (2)) made of heavy‐duty aluminum foil under a radiative heater with different powers (800, 1600, and 2400 W) and different compression lengths (0.15, 0.25, 0.35, and 0.45 m) were investigated. It was found that the Miura Ori (1) and Miura Ori (2) geometries have three to four times high‐temperature differences (the maximum temperature at the end of the heating process minus the initial temperature) than the W‐fold geometry. The Miura Ori (2) and Miura Ori (1) geometries produced high heat capacity enhancements of 1.2–3.2 times at high compression lengths that showed great potential for applications such as solar steam generators. The overall heat transfer coefficient for cooling can be controlled by changing the compression length of the origami geometry, allowing for dynamic surface temperature controls. This parameter decreases by up to 25.3%, 22.6%, and 45.9% for W‐fold, Miura Ori (1), and Miura Ori (2), respectively, in comparison to their flat states.
Neuro death through autophagy via the acetylation of FoxO1 by SIRT2 in the hippocampus of mice in a autism spectrum disorder mice model
Authors: Guo Lanmin , Jiang Zhi‐Mei , Zhan Yu‐Jun , Pan Wei , Wu Qing‐Wei , Song Fan‐Xu , Zhou Xue , Zhou Xin‐Yu , Liu Li‐Jun , Wang Jing‐Tao
Published: March 2023

Autism Spectrum Disorder (ASD) is a series of complex neurodevelopmental disorders, which can affect children's social, behavioral and communication abilities. A member of the Sirtuins family of NAD + dependent deacetylases called SIRT2 could regulate the inflammation progress during stress, but the relevant mechanism has not been clearly defined. In the present study, the ASD model of wild type and SIRT2 knock out mice was established to evaluate the impact on the homeostasis of neurons in the hippocampus using western blotting, immunofluorescence and Nissl staining. The results showed that the amplification of neuronal richness was significantly decreased and neuroinflammation increased in the hippocampus following ASD due to autophagy, caused by enhancing the acetylation of FoxO1 using SIRT2 gene deletion and indicating this should be the target for ASD or other psychological stress treatment.
iPSC‐derived tenocytes seeded on microgrooved 3D printed scaffolds for Achilles tendon regeneration
Authors: Kaneda Giselle , Chan Julie L. , Castaneda Chloe M. , Papalamprou Angela , Sheyn Julia , Shelest Oksana , Huang Dave , Kluser Nadine , Yu Victoria , Ignacio Gian C. , Gertych Arkadiusz , Yoshida Ryu , Metzger Melodie F. , Tawackoli Wafa , Vernengo Andrea , Sheyn Dmitriy
Published: March 2023

Tendons and ligaments have a poor innate healing capacity, yet account for 50% of musculoskeletal injuries in the United States. Full structure and function restoration postinjury remains an unmet clinical need. This study aimed to assess the application of novel three dimensional (3D) printed scaffolds and induced pluripotent stem cell‐derived mesenchymal stem cells (iMSCs) overexpressing the transcription factor Scleraxis (SCX, iMSCSCX+) as a new strategy for tendon defect repair. The polycaprolactone (PCL) scaffolds were fabricated by extrusion through a patterned nozzle or conventional round nozzle. Scaffolds were seeded with iMSCSCX+ and outcomes were assessed in vitro via gene expression analysis and immunofluorescence. In vivo, rat Achilles tendon defects were repaired with iMSCSCX+‐seeded microgrooved scaffolds, microgrooved scaffolds only, or suture only and assessed via gait, gene expression, biomechanical testing, histology, and immunofluorescence. iMSCSCX+‐seeded on microgrooved scaffolds showed upregulation of tendon markers and increased organization and linearity of cells compared to non‐patterned scaffolds in vitro. In vivo gait analysis showed improvement in the Scaffold + iMSCSCX+‐treated group compared to the controls. Tensile testing of the tendons demonstrated improved biomechanical properties of the Scaffold + iMSCSCX+ group compared with the controls. Histology and immunofluorescence demonstrated more regular tissue formation in the Scaffold + iMSCSCX+ group. This study demonstrates the potential of 3D‐printed scaffolds with cell‐instructive surface topography seeded with iMSCSCX+ as an approach to tendon defect repair. Further studies of cell‐scaffold constructs can potentially revolutionize tendon reconstruction by advancing the application of 3D printing‐based technologies toward patient‐specific therapies that improve healing and functional outcomes at both the cellular and tissue level.
Evaluation of articular changes using a rat mono‐iodoacetate‐induced shoulder arthritis model by histology and radiology
Authors: Ise Shohei , Ochiai Nobuyasu , Hashimoto Eiko , Hirosawa Naoya , Kajiwara Daisuke , Shimada Yohei , Inagaki Kenta , Hiraoka Yu , Hattori Fumiya , Ohtori Seiji
Published: March 2023

The rat mono‐iodoacetate (MIA) arthritis model has been used in studies on the hip, knee, and ankle joints. Few studies have explored its utility in shoulder arthritis research, and none have evaluated the effects of time and different MIA doses on arthritis progression. Therefore, we developed a rat MIA shoulder arthritis model to evaluate articular changes through radiological and histological analyses. Sprague–Dawley rats (n = 108) were equally divided into groups that were intra‐articularly injected with 0.5 mg of MIA (in 50 µL of purified water), 2.0 mg of MIA (in 50 µL of purified water), or purified water (50 µL; sham group). Throughout the study period, 18 rats (six per group) were evaluated by computed tomography and assessed using the Larsen's classification system; 90 rats were further evaluated histologically using the Osteoarthritis Research Society International scoring system. Computed tomography revealed that the groups injected with MIA developed arthritis and osteophytes 14 days after injection, which progressed temporally. The Larsen's grades worsened over time; at all time points, the scores were higher in the group injected with 2.0 mg of MIA than in the group injected with 0.5 mg of MIA. Furthermore, concurrent with the worsening Larsen's grades, the Osteoarthritis Research Society International scores also significantly increased over time; at all time points, they were higher in the group injected with 2.0 mg of MIA than in the group injected with 0.5 mg of MIA. Our rat MIA shoulder arthritis model revealed radiologically and histologically confirmed temporal and MIA dose‐dependent arthritic changes.
Effects of co‐plasticization of glycerol and small molecular esters on the physicochemical properties of extrusion‐blown high‐content starch/poly(butylene adipate‐co‐terephthalate) films
Authors: Zhai Xiaosong , Zhang Rui , Cheng Yue , Wang Wentao , Hou Hanxue
Published: March 2023

BACKGROUND

Poor mechanical and water barrier properties of starch‐based films severely restrict their applications as packaging materials. In this study, glycerol was combined with various small molecular esters (SMEs) with different molecular structures to plasticize high‐content starch/poly(butylene adipate‐co‐terephthalate) (80/20, w/w) films (SPFs) prepared by extrusion blowing. The effects of co‐plasticization on the physicochemical properties and film‐forming mechanism of SPFs were investigated.

RESULTS

The addition of glycerides to SPFs reduced intermolecular interaction, increased molecular chain mobility, and decreased glass transition, melting temperatures, and crystallinity. Mechanical and water barrier properties of SPFs were improved significantly with the co‐plasticization of glycerol and SMEs. The incorporation of triacetate glyceride increased tensile strength of SPFs by 54% and the water contact angle by up to 95°. The SPF with diacetate glyceride exhibited the minimum water vapor permeability, which decreased by 39%.

CONCLUSION

The levels of hydrophilic/hydrophobic groups in SMEs and their molecular weights were essential for the plasticizing effects. Glycerides tended to infiltrate into starch for effective plasticization compared with citrates. The combination of glycerol and glycerides had better plasticizing effects on starch. © 2023 Society of Chemical Industry.
Technical note: Comprehensive evaluations of gantry and couch rotation isocentricities for implementing proton stereotactic radiosurgery
Authors: Shen Jiajian , Robertson Daniel G. , Bues Martin , Shipulin Konstantin , Liu Wei , Stoker Joshua , Ashman Jonathan B. , Lara Pedro , Keole Sameer R. , Wong William , Vora Sujay A.
Published: March 2023

Background

Mechanical accuracy should be verified before implementing a proton stereotactic radiosurgery (SRS) program. Linear accelerator (Linac)‐based SRS systems often use electronic portal imaging devices (EPIDs) to verify beam isocentricity. Because proton therapy systems do not have EPID, beam isocentricity tests of proton SRS may still rely on films, which are not efficient.

Purpose

To validate that our proton SRS system meets mechanical precision requirements and to present an efficient method to evaluate the couch and gantry's rotational isocentricity for our proton SRS system.

Methods

A dedicated applicator to hold brass aperture for proton SRS system was designed. The mechanical precision of the system was tested using a metal ball and film for 11 combinations of gantry and couch angles. A more efficient quality assurance (QA) procedure was developed, which used a scintillator device to replace the film. The couch rotational isocentricity tests were performed using orthogonal kV x‐rays with the couch rotated isocentrically to five positions (0°, 315°, 270°, 225°, and 180°). At each couch position, the distance between the metal ball in kV images and the imaging isocenter was measured. The gantry isocentricity tests were performed using a cone‐shaped scintillator and proton beams at five gantry angles (0°, 45°, 90°, 135°, and 180°), and the isocenter position and the distance of each beam path to the isocenter were obtained. Daily QA procedure was performed for 1 month to test the robustness and reproducibility of the procedure.

Results

The gantry and couch rotational isocentricity exhibited sub‐mm precision, with most measurements within ±0.5 mm. The 1‐month QA results showed that the procedure was robust and highly reproducible to within ±0.2 mm. The gantry isocentricity test using the cone‐shaped scintillator was accurate and sensitive to variations of ±0.2 mm. The QA procedure was efficient enough to be completed within 30 min. The 1‐month isocentricity position variations were within 0.5 mm, which demonstrating that the overall proton SRS system was stable and precise.

Conclusion

The proton SRS Winston–Lutz QA procedure using a cone‐shaped scintillator was efficient and robust. We were able to verify radiation delivery could be performed with sub‐mm mechanical precision.
5 questions with Brian Piper and Stephanie Geyer
Authors: Talarico Donna
Published: March 2023

Every now and then, the Recruiting and Retaining Adult Learners marketing column will profile a communications professional (or two) via a “5 questions with” feature. Sometimes the questions will vary from column to column based on current news and trends.
Agreement of Clinician‐Administered and Modified Parent‐Administered House‐Brackmann Scales in Children with Bell's Palsy
Authors: Babl Franz E. , Eapen Nitaa , Herd David , Borland Meredith L. , Kochar Amit , Zhang Michael , Oakley Ed , Hopper Sandy M. , Berkowitz Robert G. , Wilson Catherine L. , Williams Amanda , Mackay Mark T. , Lee Katherine J. , Hearps Stephen ,   the PREDICT (Paediatric Research in Emergency Departments International Collaborative) research network
Published: March 2023

Objective

Currently there is no parent administered scale for facial nerve function in children. We set out to assess the agreement between a newly developed parent‐administered modified version of the House‐Brackmann (HB) scale and the standard clinician‐administered HB scale in children with Bell's palsy.

Study Design

Secondary analysis of a triple‐blind, randomized, placebo‐controlled trial of corticosteroids to treat idiopathic facial paralysis (Bell's palsy) in children (6 months to <18 years).

Setting

Multicenter study at pediatric hospitals with recruitment in emergency departments.

Methods

Children were recruited within 72 hours of symptom onset and assessed using the clinician‐administered and the parent‐administered modified HB scales at baseline, and at 1, 3, and 6 months until recovered. Agreement between the 2 scales was assessed using intraclass coefficient (ICC) and a Bland‐Altman plot.

Results

Data were available for 174 of the 187 children randomized from at least 1 study time point. The mean ICC between clinician and parent HB scores across all time points was 0.88 (95% confidence interval, CI: 0.86, 0.90). The ICC for the data collected at baseline was 0.53 (95% CI: 0.43, 0.64), at 1 month was 0.88 (95% CI: 0.84, 0.91), at 3 months was 0.80 (95% CI: 0.71, 0.87) and at 6 months was 0.73 (95% CI: 0.47, 0.89). A Bland‐Altman plot indicated a mean difference between the 2 scores (clinician‐reported minus parent‐reported) of only −0.07 (95% limits of agreement −1.37 to 1.23).

Conclusion

There was good agreement between the modified parent‐administered and the clinician‐administered HB scales.
Trends in Swallowing Outcomes Following Deintensified Treatment in Selected p16+ Oropharyngeal Carcinoma
Authors: Lee Esther , Magge Hari , Park Isabel , Shakhtour Leyn , Li Ning‐Wei , Schottler Jennifer , Joshi Arjun S. , Thakkar Punam G. , Goodman Joseph F.
Published: March 2023

Objective

Identify trends in swallowing outcomes in p16+ oropharyngeal squamous cell carcinoma following neoadjuvant chemotherapy+surgery (NAC+S) versus neoadjuvant chemotherapy+surgery+radiation (NAC+S+R).

Study Design

Cohort study.

Setting

Single academic institution.

Methods

Swallowing outcome was measured using a validated questionnaire, MD Anderson Dysphagia Inventory (MDADI). MDADI scores were compared between NAC+S and NAC+S+R groups in short‐term (<1 year), middle‐term (1‐3 years), and long‐term (>3 years). Clinical factors associated with MDADI scores were explored using a linear mixed model. Statistical significance was established at p < .05.

Results

Sixty‐seven patients met the inclusion criteria and were divided into 2 groups: NAC+S (57 [85.1%]) and NAC+S+R (10 [14.9%]). All patients had improved MDADI scores in the middle‐term compared to short‐term (NAC+S: score increase = 3.43, p = .002; NAC+S+R: score increase = 11.18, p = .044), long‐term compared to short‐term (NAC+S: score increase = 6.97, p < .001; NAC+S+R: score increase = 20.35, p < .001), and long‐term compared to middle‐term (NAC+S: score increase = 3.54, p = .043; NAC+S+R: score increase = 9.18, p = .026). NAC+S patients had better MDADI scores than NAC+S+R patients at short‐term (83.80 vs 71.26, p = .001). There was no significant difference in swallowing function in the middle‐term or long‐term.

Conclusion

Regardless of treatment type, swallowing will likely be improved in the middle‐term and long‐term compared to the short‐term. Patients treated with NAC+S+R will have worse short‐term swallowing function. However, in the middle‐term and long‐term, there is no significant difference in swallowing function between patients treated with NAC+S and NAC+S+R.
Simulation models investigating the dynamic characteristics of shock isolators
Authors: Clasen Michael , Sachau Delf
Published: March 2023

In the marine environment, naval vessels are often influenced by underwater compression waves. Transport and dangerous goods require advanced protection beyond linear, static considerations. Therefore with regard to shock influence, the dynamic characteristics of helical wire‐cable‐isolators are investigated. The shock impact is given by basepoint acceleration measurement data exciting a mechanical model observing nonlinear stiffness as well as hysteretic damping effects. Three simulation models are presented here: the advanced Kelvin‐Voigt model, the join patch model and the modified Bouc‐Wen‐Model. A comparison between simulation and measurement results is given.
A Machine Learning Enabled Image‐data‐driven End‐to‐end Mechanical Field Predictor For Dual‐Phase Steel
Authors: Lin Binbin , Medghalchi Setareh , Korte-Kerzel Sandra , Xu Bai-Xiang
Published: March 2023

This contribution presents convolutional neural nets (CNN) based surrogate models for prediction of von Mises stress and equivalent plastic strain fields of commonly used Dual‐Phase (DP) steels in automotive applications. The models predict field quantities in an end‐to‐end manner, driven by segmented phase images from real experimental scanning electron micrographs as inputs and FEM calculations as outputs. Hereby, we train CNN models with the U‐net neural network structure based on around 900 elastoplastic FEM simulations of various DP steel microstructure samples under tensile test. The trained CNN models are validated and tested on 250 and 50 samples, respectively. Thereby CNN models are employed sequentially for different tasks , from the real micrographs to segmented phase maps, then from segmented phase maps to stress, strain field predictions, in an end‐to‐end manner. The field predictor model results show good agreement with the test data and convincing performance on unseen microstructural dataset. This work demonstrates the large potential of a Machine Learning model to make accumulatively use of the physics‐based simulation data of large number of boundary value problems with varying microstructure. It recaptures not only the physics, implied in each simulation training data obtained from the partial different governing equations of mechanics, but also the overarching correlation between the microstructure and the stress and strain field responses.
Eigenvalue Optimization with respect to Shape‐Variations in Electromagnetic Cavities
Authors: Herter Christine , Schöps Sebastian , Wollner Winnifried
Published: March 2023

The article considers the optimization of eigenvalues in electromagnetic cavities by means of shape variations. The field distribution and its frequency in a radio‐frequency cavity are governed by Maxwell's eigenvalue problem. To this end, we utilize a mixed formulation by Kikuchi (1987) and a mixed finite element discretization by means of Nédélec and Lagrange elements. The shape optimization is based on the method of mappings, where a Piola transformation is utilized to assert conformity of the mapped spaces. We derive the derivatives by the use of adjoint calculus for the constraining Maxwell eigenvalue problem. In two numerical examples, we demonstrate the functionality of this method.
Enhanced Hamiltonian Monte Carlo simulations using Hamiltonian neural networks
Authors: Thaler Denny , Dhulipala Somayajulu L. N. , Bamer Franz , Markert Bernd , Shields Michael D.
Published: March 2023

Markov Chain Monte Carlo simulations form an essential tool for exploring high‐dimensional target distributions. Metropolis developed a fundamental random walk algorithm which was improved by Hastings later. The result is known as the Metropolis‐Hastings algorithm, which enables the exploration of multi‐dimensional distributions. The main drawbacks of this algorithm are its high auto‐correlation and slow exploration of the target distribution space. In order to increase efficiency, researchers have proposed various modifications to this algorithm. In particular, the Hamiltonian Monte Carlo simulation enhances the efficient exploration of the target probability density. The algorithm uses mechanisms inspired by Hamiltonian dynamics to propose a new sample for the target distribution. For reliability analysis, the incorporation of subset simulation and Hamiltonian Monte Carlo methods has shown promising results. However, using the Hamiltonian Monte Carlo method to sample is computationally expensive, especially when dealing with high‐dimensional problems and performing several steps to propose a new state. In this contribution, we show the general applicability of Hamiltonian neural networks to speed up the proposal of new samples within the Hamiltonian Monte Carlo method.
Numerical analysis of stress tensor mapping without an external solver
Authors: Wagner Jérôme , Dröder Klaus , Thater Raphael , Hürkamp André
Published: March 2023

To further the accuracy of a virtual process, links between sequenced numerical methods are established to create a process chain, which considers all influences on a manufactured part in its early design stages. In order to transform numerical results into initial conditions of a preceding simulation method, the data is “mapped" from a source to a target finite element mesh. The data transfer depends heavily on the difference in mesh discretization as well as the utilized interpolation method. Errors occur using different inter‐ and extrapolation methods. This contribution aims to establish a hybrid interpolation method to transfer tensorial stress data between FEM meshes without using an external solver. The applied method consists partly of a radial basis and of a weighted areas interpolation.
Phenomenological material model for damage in steel‐fiber reinforced high performance concrete during low cycle fatigue
Authors: Pise Mangesh , Brands Dominik , Schröder Jörg , Gebuhr Gregor , Anders Steffen
Published: March 2023

A phenomenological material model is developed to understand the pseudo‐ductile material behavior of steel fiber reinforced high performance concrete (HPC) during failure. In that respect, an energy function is formulated using an additive composition of a transversal isotropic elasto‐plastic model and an elasto‐plastic phase‐field model representing the individual behavior of the steel fibers and the concrete material, respectively. Comparing the experimental data and numerical results of three‐point bending beam tests at low cycle for steel fiber reinforced HPCs, the efficiency of the presented model is verified.
Modeling simultaneous momentum and passive scalar transfer in turbulent annular Poiseuille flow
Authors: Tsai Pei-Yun , Schmidt Heiko , Klein Marten
Published: March 2023

Simultaneous momentum and passive scalar transfer in weakly heated pressure‐driven turbulent concentric annular pipe flow is numerically investigated using the cylindrical formulation of the stochastic one‐dimensional turbulence (ODT) model, which is utilized here as standalone tool. In the present study, we focus on the model calibration for heated annular pipes based on recent reference direct numerical simulations (DNS) from Bagheri and Wang (Int. J. Heat Fluid Flow 86, 108725, 2020; Phys. Fluids 33, 055131, 2021). It is shown that the model is able to individually capture scalar and momentum transfer, but not both equally well at the same time. We attribute this to less dissimilar scalar and momentum transport in the model at the low Reynolds number investigated. It is argued that the model prefers a fully developed turbulent state due to its construction. Nevertheless, it is demonstrated that ODT is able to reasonably capture the radial inner‐outer asymmetry of the scalar and momentum boundary layers which yields better predictive capabilities than wall‐function‐based approaches.
A mesoscale model of non‐crimp fabrics based on a deep learning framework
Authors: Zhou Shuang , Hillgärtner Markus , Abdusalamov Rasul , X. Duong Thang , Itskov Mikhail
Published: March 2023

Non‐crimp fabrics (NCFs) are a type of textile characterized by straight and long fibers. Due to their lightweight structures, they are widely used for fiber‐reinforced composites in automotive, aerospace, and other fields. NCFs consist of several differently oriented layers of unidirectional fibers, stacked on top of each other, and stitched together by stitching yarns. Due to this structure, constitutive modeling of the anisotropic properties of NCFs is still challenging requiring an accurate description, especially for multi‐axial loading.

In this work, a deep learning framework constructed by artificial neural networks (ANNs) is presented that describes the constitutive behavior of NCFs. Such a framework is able to learn not only from the provided load‐displacement relation by experimental data of existing materials, but also from additional relevant information, such as geometric characteristics. The framework allows predicting the constitutive behavior of new fabric materials, whose experimental data are unavailable yet.

This contribution aims to establish a constitutive model of dry NCFs based on a deep learning framework trained from virtual experimental data provided by finite element simulations of representative volume elements (RVEs) at the mesoscale. NCFs with only two families of fibers perpendicular to each other and stitched together are considered. The proposed constitutive model is capable of predicting the in‐plane material response of NCFs under arbitrary multi‐axial loading conditions. To this end, a procedure of training ANN for reaction forces responding to displacements of RVEs is investigated.

In order to guarantee the predictive capability for various NCFs under multi‐axial loading conditions, the artificial neural network is used to learn from simulations of the same RVE provided by changing its fiber bundle properties (tensile moduli and shear moduli) and loading directions at the mesoscale. Finally, the proposed constitutive model is verified by comparing the predictive results with reference data sets for various materials in arbitrary axial loading.
Graph Neural Network enhanced Finite Element modelling
Authors: Gulakala Rutwik , Markert Bernd , Stoffel Marcus
Published: March 2023

In this study, we introduce a Graph network‐enhanced Finite Element approach to accelerate Finite Element simulations. We utilize the discretized geometry from a Finite Element pre‐processor to establish the graph and use the Graph Neural Network to solve the boundary value problem of the discretized domain. The advantage of graph neural networks is that they have a similar structure as compared to a discretized domain with nodes and elements. The underlying dynamics of the system are computed via a learned message‐passing. The goal here is to enhance and accelerate the FEM simulations using the proposed GNN network by incorporating the underlying mechanics knowledge into the network to enhance the generalizing ability of the network on various loading and boundary conditions. All the proposed studies in the literature where graph networks are applied to Finite Element Methods use images as input and output. The advantage of the proposed model is that it takes inputs such as the nodal information, their corresponding edges, nodal coordinates and the boundary conditions for each particular node from a Finite Element pre‐processor and computes the von‐Mises stress at each node along with their edge connections as output that can be read by a Finite Element post‐processor.
Characteristics and completeness of spontaneous reports by reporter's role in Germany: An analysis of the EudraVigilance database using the example of opioid‐associated abuse, dependence, or withdrawal
Authors: Jobski Kathrin , Bantel Carsten , Hoffmann Falk
Published: March 2023

Spontaneous reporting is based on the experience of all healthcare professionals (HCPs) but also consumers/non‐HCPs and therefore reveals a broad picture of a drug's adverse reactions. Recent studies found substantial differences between reports from these varying sources including the reports' completeness. Using the example of opioid‐associated abuse, dependence, or withdrawal, this study analyzed the completeness and characteristics of spontaneous reports from Germany focusing on the reporter. Based on EudraVigilance data, we included all cases of abuse, dependence, or withdrawal associated with opioids indicated for pain therapy and filed from Germany until 2018. Completeness and characteristics were analyzed by a reporter (physician, pharmacist, other HCPs, consumers/non‐HCPs) and also by time period to account for other influencing factors. In total, 1721 cases were included, mainly filed by physicians (38.5%) and pharmacists (30.7%). Completeness of demographics varied from 74.5% (other HCPs) to 42.7% (consumers/non‐HCPs). Consumers/non‐HCPs most often provided any indication/comorbidity (75.2%), whereas this was the case for only 20.2% of pharmacists. Large differences between the reporters were found for almost all characteristics. Other HCPs far more often coded a history of drug abuse, dependence, or withdrawal than other reporters (46.9% vs. 11.6%–24.2%, respectively), and fatal outcomes were also mainly filed by other HCPs (68.1% vs. 14.8%–20.4% by all other reporters). Differences in completeness and characteristics were also observed over time. Studies analyzing spontaneous data should consider potential differences between the various reporting groups in terms of completeness and characteristics. Further, the impact of other influencing factors has to be assessed.
Highly Sensitive Hydrogen Sulfide Sensor Based on GaN/GaInN Heterostructure
Authors: Shahbaz Jassim , Scholz Ferdinand
Published: March 2023

Accurate detection of gases such as hydrogen sulfide in the exhaled human breath is of great interest for medical professionals as it can possibly help in the early detection of organ malfunction and other diseases. GaInN heterostructure sensors are sensitive to the changes in the surface potential caused by the adsorption of gas molecules. A quantum well (QW) placed close to the surface experiences a change in the quantum‐confined Stark effect and as a result shifts its photoluminescence signal. Several parameters of the GaInN sensors grown by metal organic vapor phase epitaxy are optimized such as the GaN cap layer, QW thickness, and doping concentration. Moreover, how various metal functionalization layers can improve its sensitivity and selectivity is investigated. Gold (Au) and Silver (Ag) shows sensitivity to hydrogen sulfide in the 10–100 parts per billion (ppb) range. Ammonia gas is also detected in the 5–10 range (ppm) with a sensor structure covered with a thin gold layer.
Exploring Zn doped η′‐Cu6Sn5: Structural stability, fracture toughness and thermal conductivity
Authors: Li Bo , Yang Ancang , Peng Mingjun , Duan Yonghua
Published: March 2023

In order to investigate the effect of alloying elements on mechanical properties of η′‐Sn‐Cu alloys, the effect of Zn‐doping on the structural stability, elasticity, electrical and thermodynamic properties of η′‐Cu6Sn5 intermetallic in Sn‐Cu alloys have been calculated by first‐principles calculations. The results show that the Zn‐doped η′‐Cu6Sn5 are thermodynamically and dynamically stable. The doped phase is the most stable when Zn replaces Cu1 site. The bulk modulus and shear modulus of η′‐Cu6Sn5 with Zn‐doped Sn1 site are the highest. When Zn replaces Sn, the stiffness is stronger than that when Zn replaces Cu, and the stiffness order is Zn–Sn > Zn–Cu > η′‐Cu6Sn5. Compared with other doping sites, the 3D surface configurations of elastic modulus of Zn–Sn1 η′‐Cu6Sn5 are the largest. In addition, Zn doping improves the fracture toughness and chemical bond strength of the material. The thermal conductivity and electron thermal conductivity of η′‐Cu6Sn5 also increased.
Structure and thermodynamic properties of adducts based on cucurbit[6]uril and Fe(III)/Fe(II) aqua complexes: A DFT examination
Authors: Masliy A. N. , Grishaeva T. N. , Kuznetsov A. M.
Published: March 2023

This study carried out a detailed step‐by‐step PBE/TZVP level analysis of the inclusion of Fe(III)/Fe(II) aqua complexes into the cavity of cucurbit[6]urils (CB[6]). The structural characteristics of all intermediate stable structures formed during the inclusion process from the bulk of aqueous solution to the inclusion compound were obtained. To account for solvation effects, a molecular‐continuum model was used in which six water molecules of the first coordination sphere of aqua complexes and 12 water molecules of the second coordination sphere were taken into account, while the interaction of such a supermolecule with a dielectric medium was accounted within the continuum model (PCM) [Correction added on 9 June 2023, after first online publication. The word molecular continual has been changed to molecular‐continuum in the sentence.]. The process of incorporation of the aqua complex into the cavity was found to be accompanied by a partial desolvation of the second coordination sphere of the aqua complex and a change in the structure of the first coordination sphere. Additionally, the standard electrode potential of the half‐reaction Fe3+(aq) + e = Fe2+(aq) was estimated for all adducts formed in the reaction.
DNA Mold‐Based Fabrication of Palladium Nanostructures
Authors: Kemper Ulrich , Ye Jingjing , Poppitz David , Gläser Roger , Seidel Ralf
Published: March 2023

DNA origami molds allow a shape‐controlled growth of metallic nanoparticles. So far, this approach is limited to gold and silver. Here, the fabrication of linear palladium nanostructures with controlled lengths and patterns is demonstrated. To obtain nucleation centers for a seeded growth, a synthesis procedure of palladium nanoparticles (PdNPs) using Bis(p‐sulfonatophenyl)phenylphosphine (BSPP) both as reductant and stabilizer is developed to establish an efficient functionalization protocol of the particles with single‐stranded DNA. Attaching the functionalized particles to complementary DNA strands inside DNA mold cavities supports subsequently a highly specific seeded palladium deposition. This provides rod‐like PdNPs with diameters of 20–35 nm of grainy morphology. Using an annealing procedure and a post‐reduction step with hydrogen, homogeneous palladium nanostructures can be obtained. With the adaptation of the procedure to palladium the capabilities of the mold‐based tool‐box are expanded. In the future, this may allow a facile adaptation of the mold approach to less noble metals including magnetic materials such as Ni and Co.
Pseudo‐Hydrodynamic Flow of Quasiparticles in Semimetal WTe2 at Room Temperature
Authors: Choi Young‐Gwan , Doan Manh‐Ha , Ngoc Luu Ly Pham , Lee Junsu , Choi Gyung‐Min , Chernodub Maxim Nikolaevich
Published: March 2023

Recently, much interest has emerged in fluid‐like electric charge transport in various solid‐state systems. The hydrodynamic behavior of the electronic fluid reveals itself as a decrease of the electrical resistance with increasing temperature (the Gurzhi effect) in narrow channels, polynomial scaling of the resistance as a function of the channel width, violation of the Wiedemann–Franz law supported by the emergence of the Poiseuille flow. Similar to whirlpools in flowing water, the viscous electronic flow generates vortices, resulting in abnormal sign‐changing electrical response driven by backflow. However, the question of whether the long‐ranged sign‐changing electrical response can be produced by a mechanism other than hydrodynamics has not been addressed so far. Here polarization‐sensitive laser microscopy is used to demonstrate the emergence of visually similar abnormal sign‐alternating patterns in semi‐metallic tungsten ditelluride at room temperature where this material does not exhibit true hydrodynamics. It is found that the neutral quasiparticle current consisting of electrons and holes obeys an equation remarkably similar to the Navier–Stokes equation. In particular, the momentum relaxation is replaced by the much slower process of quasiparticle recombination. This pseudo‐hydrodynamic flow of quasiparticles leads to a sign‐changing charge accumulation pattern via different diffusivities of electrons and holes.
Separator with Nitrogen–Phosphorus Flame‐Retardant for LiNixCoyMn1−x−yO2 Cathode‐Based Lithium‐Ion Batteries
Authors: Han Chengyu , Cao Yu , Zhang Shaojie , Bai Liyang , Yang Ming , Fang Siyu , Gong Haochen , Tang Di , Pan Fusheng , Jiang Zhongyi , Sun Jie
Published: March 2023

With the pursuit of high‐energy‐density for lithium‐ion batteries (LIBs), the hidden safety problems of batteries have gradually emerged. LiNixCoyMn1−x−yO2 (NCM) is considered as an ideal cathode material to meet the urgent needs of high‐energy‐density batteries. However, the oxygen precipitation reaction of NCM cathode at high temperature brings serious safety concerns. In order to promote high‐safety lithium‐ion batteries, herein, a new type of flame‐retardant separator is prepared using flame‐retardant (melamine pyrophosphate, MPP) and thermal stable Poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP). MPP takes the advantage of nitrogen–phosphorus synergistic effect upon the increased internal temperature of LIBs, including the dilution effect of noncombustible gas and the rapidly suppression of undesirable thermal runaway. The developed flame‐retardant separators show negligible shrinkage over 200 °C and it takes only 0.54 s to extinguish the flame in the ignition test, which are much superior to commercial polyolefin separators. Moreover, pouch cells are assembled to demonstrate the application potential of PVDF‐HFP/MPP separators and further verify the safety performance. It is anticipated that the separator with nitrogen–phosphorus flame‐retardant can be extensively applied to various high‐energy‐density devices owing to simplicity and cost‐effectiveness.
A Bioinspired Ultra Flexible Artificial van der Waals 2D‐MoS2 Channel/LiSiOx Solid Electrolyte Synapse Arrays via Laser‐Lift Off Process for Wearable Adaptive Neuromorphic Computing
Authors: Hwang Yunjeong , Park Byeongjin , Hwang Seungkwon , Choi Soo‐Won , Kim Han Seul , Kim Ah Ra , Choi Jin Woo , Yoon Jongwon , Kwon Jung‐Dae , Kim Yonghun
Published: March 2023

Wearable electronic devices with next‐generation biocompatible, mechanical, ultraflexible, and portable sensors are a fast‐growing technology. Hardware systems enabling artificial neural networks while consuming low power and processing massive in situ personal data are essential for adaptive wearable neuromorphic edging computing. Herein, the development of an ultraflexible artificial‐synaptic array device with concrete‐mechanical cyclic endurance consisting of a novel heterostructure with an all‐solid‐state 2D MoS2 channel and LiSiOx (lithium silicate) is demonstrated. Enabled by the sequential fabrication process of all layers, by excluding the transfer process, artificial van der Waals devices combined with the 2D‐MoS2 channel and LiSiOx solid electrolyte exhibit excellent neuromorphic synaptic characteristics with a nonlinearity of 0.55 and asymmetry ratio of 0.22. Based on the excellent flexibility of colorless polyimide substrates and thin‐layered structures, the fabricated flexible neuromorphic synaptic devices exhibit superior long‐term potentiation and long‐term depression cyclic endurance performance, even when bent over 700 times or on curved surfaces with a diameter of 10 mm. Thus, a high classification accuracy of 95% is achieved without any noticeable performance degradation in the Modified National Institute of Standards and Technology. These results are promising for the development of personalized wearable artificial neural systems in the future.
Boosting Charge Mediation in Ferroelectric BaTiO3−x‐Based Photoanode for Efficient and Stable Photoelectrochemical Water Oxidation
Authors: Zhao Yue , Ran Lei , Chen Rui , Song Yurou , Gao Junfeng , Sun Licheng , Hou Jungang
Published: March 2023

Oxygen evolution reaction (OER) is a bottleneck to photoelectrochemical (PEC) water splitting; however, there remains an impressive challenge for intrinsic charge transport for the development of integrated photoanodes. Herein, covalent triazine frameworks as conjugated molecules are grafted on the surfaces of ferroelectric BaTiO3−x (CTF/BTO) nanorod array, and then oxyhydroxide oxygen evolution cocatalyst (OEC) is constructed as an integrated photoanode. The OEC/CTF/BTO array not only achieves a high photocurrent density of 0.83 mA cm−2 at 1.23 V versus reversible hydrogen electrode (vs RHE) and low onset potential of ≈0.23 VRHE, but also optimizes outstanding stability. To disclose the origin, the enhanced PEC activity can be contributed to the integration of CTF and OEC, enhancing light‐harvesting capability, boosting charge carrier mediation, and promoting water oxidation kinetics through electrochemical analysis and density functional theory calculations. This study not only provides an alternative to accelerate charge transfer, but also paves the rational design and fabrication of integrated photoanodes for boosting PEC water splitting performance.