bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of metal‐polymer composites manufactured by fused deposition modeling with regard to process parameters
Authors: Moritzer Elmar , Elsner Christian Lennart , Schumacher Christian 
Published: September 2021

AbstractA comparatively new approach for the manufacturing of metal parts is the use of fused deposition modeling (FDM). Here, a metal powder filled filament is processed to manufacture components (green part). The subsequent process chain is identical to that of metal injection molding (MIM). Thus, the polymer binder is initially removed from the component (brown part). The metal particles are finally sintered in a furnace to form a pure metal component (white part/final part). The aim of this study is the investigation of the FDM process for the fabrication of metal components with regard to process parameters. This includes the consideration of material‐specific parameters influencing the extrusion process. Especially, the material temperature and material behavior within the FDM nozzle are analyzed. On this basis, the mechanical properties of specimens manufactured with different nozzle sizes and strand geometries are examined. The resulting properties are used to evaluate the suitability of the specific strand‐nozzle combination for processing the metal‐polymer composite. In particular, the density of the components and the process reliability are important evaluation criteria. Finally, the comparison of white parts with parts manufactured in selective laser melting (SLM) shows the possibilities offered by processing metal‐polymer composites in FDM.
A glutamate concentration‐biased allosteric modulator potentiates NMDA‐induced ion influx in neurons
Authors: Costa Blaise M. , Kwapisz Lina Cortés , Mehrkens Brittney , Bledsoe Douglas N. , Vacca Bryanna N. , Johnston Tullia V. , Razzaq Rehan , Manickam Dhanasekaran , Klein Bradley G. 
Published: September 2021

AbstractPrecisely controlled synaptic glutamate concentration is essential for the normal function of the N‐methyl D‐aspartate (NMDA) receptors. Atypical fluctuations in synaptic glutamate homeostasis lead to aberrant NMDA receptor activity that results in the pathogenesis of neurological and psychiatric disorders. Therefore, glutamate concentration‐dependent NMDA receptor modulators would be clinically useful agents with fewer on‐target adverse effects. In the present study, we have characterized a novel compound (CNS4) that potentiates NMDA receptor currents based on glutamate concentration. This compound alters glutamate potency and exhibits no voltage‐dependent effect. Patch‐clamp electrophysiology recordings confirmed agonist concentration‐dependent changes in maximum inducible currents. Dynamic Ca2+ and Na+ imaging assays using rat brain cortical, striatal and cerebellar neurons revealed CNS4 potentiated ion influx through native NMDA receptor activity. Overall, CNS4 is novel in chemical structure, mechanism of action and agonist concentration‐biased allosteric modulatory effect. This compound or its future analogs will serve as useful candidates to develop drug‐like compounds for the treatment of treatment‐resistant schizophrenia and major depression disorders associated with hypoglutamatergic neurotransmission.
Effect of aphid biology and morphology on plant virus transmission
Authors: Jayasinghe Wikum H , Akhter Md Shamim , Nakahara Kenji , Maruthi Midatharahally N 
Published: September 2021

AbstractAphids severely affect crop production by transmitting many plant viruses. Viruses are obligate intracellular pathogens that mostly depend on vectors for their transmission and survival. A majority of economically important plant viruses are transmitted by aphids. They transmit viruses either persistently (circulative or non‐circulative) or non‐persistently. Plant virus transmission by insects is a process that has evolved over time and is strongly influenced by insect morphological features and biology. Over the past century, a large body of research has provided detailed knowledge of the molecular processes underlying virus‐vector interactions. In this review, we discuss how aphid biology and morphology can affect plant virus transmission. © 2021 Society of Chemical Industry.
Input–output‐driven gain‐adaptive iterative learning control for linear discrete‐time‐invariant systems
Authors: Liu Chuyang , Ruan Xiaoe 
Published: September 2021

AbstractFor a class of linear discrete‐time‐invariant systems repetitively operated in a finite time length, an iterative correction algorithm is exploited to identify the system Markov parameters with multi‐operation inputs and outputs in obeying a criterion, of which the time order of the corrector is adaptive to the time order of the controller. Interactively, an adaptive iterative learning control is architected which composes the compensator with the approximated Markov parameters and the tracking error in sequentially minimizing a quadratic objective function of the tracking error and the compensation. Algebraic manipulation achieves that the Markov parameters correction error is monotonically declining without any step parameter selection. Further, a rigorous derivation clarifies that the time order of the learning compensator must agree to the relative degree of the system and the tracking error is linearly monotonously convergent if the Markov parameters correction error falls into an allowable range. Inspiringly, the methods and results release the confinement to both the correction and the learning ratios. In addition, a smaller learning ratio factor tolerates a larger Markov parameters correction error. Numerical experiments support the significance and the validity.
Adaptive time‐varying formation control of uncertain Euler–Lagrange systems with event‐triggered communication
Authors: Long Jiang , Wang Wei , Liu Kexin , Huang Jiangshuai 
Published: September 2021

AbstractThis article is concerned with time‐varying formation control of networked Euler–Lagrange systems in the presence of unknown system parameters and event‐triggered communication. Under a directed graph condition, a novel distributed adaptive formation control scheme is proposed. In order to reduce the communication burden among connected agents, a dynamic triggering condition is designed without the need of continuous monitoring of neighboring states. Zeno behavior that may exist in each agent can be rigorously excluded by introducing a dynamic variable into the triggering condition. It is shown that with the proposed control scheme, all the closed‐loop signals are uniformly bounded and all the agents' generalized coordinates can form a time‐varying formation configuration. The effectiveness of the proposed control scheme is validated with simulation results.
Bounded inputs total energy shaping for a class of underactuated mechanical systems
Authors: J. Harandi M. Reza , Taghirad Hamid D. , Molaei Amir , Guadalupe Romero Jose 
Published: September 2021

AbstractDesigning control systems with bounded input is a practical consideration since realizable physical systems are limited by the saturation of actuators. The actuators' saturation degrades the performance of the control system, and in extreme cases, the stability of the closed‐loop system may be lost. However, actuator's saturation is typically neglected in the design of control systems, with compensation being made in the form of overdesigning the actuator or by postanalyzing the resulting system to ensure acceptable performance. The bounded input control of fully actuated mechanical systems has been investigated in multiple studies, but it is not generalized for underactuated mechanical systems. This article proposes a systematic framework for finding the upper bound of control effort in underactuated systems, based on interconnection and the damping assignment passivity based control approach. The proposed method also offers design variables for the control law to be tuned, considering the actuator's limit. The primary difficulty in finding the control input upper bounds is the velocity‐dependent kinetic energy‐related terms. Thus, the upper bound of velocity is computed using a suitable Lyapunov candidate as a function of closed‐loop system parameters. The validity and application of the proposed method are investigated in detail through two benchmark systems simulations.
New insights into the origin and evolution of glossic features in coarse‐textured soils in northern lower Michigan (USA)
Authors: Baish Christopher J. , Schaetzl Randall J. 
Published: September 2021

AbstractAlthough glossic horizons are widespread throughout the Great Lakes region (USA), any type of detailed empirical investigation of their genesis has not been conducted for decades. In this study, we investigated a well‐drained Haplic Glossudalf formed in calcareous till in northern Michigan and examined its glossic features across five stages of development, from nondegraded to completely degraded. Along this sequence, the glossic horizon is formed from a Bt horizon, then destroyed, evolving into an E horizon. Argillic horizon degradation is initiated from the top downward, along discrete percolation pathways. Here, temporary, highly localized, anoxic conditions favor the reduction and eluviation of Fe oxides associated with argillans. After Fe removal, clay, and to lesser extent fine silt, in the argillans become mobilized. This process results in bleached, E horizon interfingerings that penetrate the upper Bt horizon. Although eluviation of clay and fine silt is required for glossic horizon formation, their removal follows a distinct pathway from fine clay through coarse clay, and finally fine silt. This research documents the importance of redox processes at microsites in the upper Bt horizon as the destabilizing trigger for glossic horizon formation. Redox processes and microerosion may be more important than the traditionally accepted view of destabilization of clay floccules by loss of basic cations from the exchange complex. We also note that lessivage, as traditionally defined, in these soils is associated with not just clay translocation, but also fine silt.
Apparent kinetic properties of soil phosphomonoesterase and β‐glucosidase are disparately influenced by pH
Authors: Li Chongyang , Margenot Andrew J. 
Published: September 2021

AbstractExtracellular enzymes catalyze organic matter transformations in soils, yet the study of soil enzymes does not typically evaluate how enzyme kinetic properties that govern activity in situ may shift with environmental parameters such as pH. To test this, we quantified changes in apparent kinetic properties (maximum catalysis rate [AppVmax] and substrate concentration that produces 50% of Vmax [AppKm]) of soil phosphomonoesterase (PME) and β‐glucosidase (BG) as a function of pH by using dual gradients of buffer pH (3–12) and substrate concentrations in a selected set of diverse soils. A third kinetic property, apparent specificity constant (AppKa = AppVmax/AppKm) was also evaluated as a function of pH. Results indicated widely differing pH optima of soil PME and BG AppVmax and AppKm, decoupling of which entailed unpredictable pH optima of AppKa. Additionally, changes in soil enzyme activity with pH may not be driven by shifts in the specificity constant because pH–AppVmax relationships are largely unrelated to co‐occurring changes in AppKa. These results invalidate the assumption that Km of a soil enzyme is constant across pH and emphasize the importance of assaying soil enzyme activities at sufficiently high (5 × Km) substrate concentrations at a given pH to avoid the mischaracterizing pH optima.
Hydrophobic Effect on Alkaline Stability of Graft Chains in Ammonium‐type Anion Exchange Membranes Prepared by Radiation‐Induced Graft Polymerization
Authors: Hamada Takashi , Zhao Yue , Yoshimura Kimio , Radulescu Aurel , Ohwada Kenji , Maekawa Yasunari 
Published: September 2021

AbstractVinylbenzyltrimethylammonium hydroxide (VBA) and styrene (St) cografted poly(ethylene‐co‐tetrafluoroethylene) anion exchange membranes (VBA/St‐AEM) were prepared by the radiation‐induced graft polymerization of chloromethylstyrene and St and sequential quaternization and anion exchange reactions. Increasing the St content in the grafts to 63 % resulted in a gradual 21 % and 34 % decrease in the conductivity and water uptake, respectively, compared to those in the VBA‐homo‐grafted AEM. AEMs with a higher St content (81 %) showed a 9 % and 18 % higher conductivity and water uptake, respectively. Small‐angle neutron scattering showed that the sudden growth of “water puddles” consisting of water‐rich nano‐domains dispersed randomly in phase‐separated hydrophilic ion channels enhanced the conductivity and water uptake. In the alkaline durability test of VBA/St‐AEM in 1 M potassium hydroxide at 80 °C for 720 h, the loss of the conductivity was suppressed from 43 % to 8 %, when the St contents in the grafts were increased from 0 % to 63 %.
Donor–Acceptor Competition via Halide Vacancy Filling for Oxygen Detection of High Sensitivity and Stability by All‐Inorganic Perovskite Films
Authors: Xing Weiwei , Yao Qianqian , Zhu Wenpeng , Jiang He , Zhang Xiaoyue , Ji Ye , Shao Jian , Xiong Weiming , Wang Biao , Zhang Bangmin , Luo Xin , Zheng Yue 
Published: September 2021

AbstractOxygen detection by organic–inorganic halide perovskites (OIHPs) has demonstrated advantages in operating temperature, response time, and reversibility over traditional materials. However, OIHPs can only sense O2 in light and the unavoidable O2 exposure during detection easily induces the degradation of OIHPs. The trade‐off between sensitivity and stability makes the OIHP‐based oxygen sensors impractical. By replacing organic groups with Cs, the compact films of all‐inorganic halide perovskites (AIHPs) that can adsorb O2 at grain boundaries in dark are developed. AIHPs show conductance increase of 1875.5% from 1 × 10−5 to 700 Torr of O2 pressure, associated with full reversibility and long‐term stability. Combining experiments and modeling, this work reveals the donor–acceptor competition via halide vacancy filling leading to the modulation of carrier concentration and mobility. This work offers understandings on oxygen sensing by perovskite materials and paves the way for further optimization of AIHPs as promising oxygen sensors with high sensitivity and stability.
Extended Barrier Lifetime of Partially Cracked Organic/Inorganic Multilayers for Compliant Implantable Electronics
Authors: Kim Kyungjin , Van Gompel Matthias , Wu Kangling , Schiavone Giuseppe , Carron Julien , Bourgeois Florian , Lacour Stéphanie P. , Leterrier Yves 
Published: September 2021

AbstractFlexible and soft bioelectronics display conflicting demands on miniaturization, compliance, and reliability. Here, the authors investigate the design and performance of thin encapsulation multilayers against hermeticity and mechanical integrity. Partially cracked organic/inorganic multilayer coatings are demonstrated to display surprisingly year‐long hermetic lifetime under demanding mechanical and environmental loading. The thin hermetic encapsulation is grown in a single process chamber as a continuous multilayer with dyads of atomic layer deposited (ALD) Al2O3‐TiO2 and chemical vapor deposited Parylene C films with strong interlayer adhesion. Upon tensile loading, tortuous diffusion pathways defined along channel cracks in the ALD oxide films and through tough Parylene films efficiently postpone the hermeticity failure of the partially cracked coating. The authors assessed the coating performance against prolonged exposure to biomimetic physiological conditions using coated magnesium films, platinum interdigitated electrodes, and optoelectronic devices prepared on stretchable substrates. Designed extension of the lifetime preventing direct failures reduces from over 5 years yet tolerates the lifetime of 3 years even with the presence of critical damage, while others will directly fail less than two months at 37 °C. This strategy should accelerate progress on thin hermetic packaging for miniaturized and compliant implantable electronics.
Identification of Topotactic Surface‐Confined Ullmann‐Polymerization
Authors: Dettmann Dominik , Galeotti Gianluca , MacLean Oliver , Tomellini Massimo , Di Giovannantonio Marco , Lipton‐Duffin Josh , Verdini Alberto , Floreano Luca , Fagot‐Revurat Yannick , Perepichka Dmitrii F. , Rosei Federico , Contini Giorgio 
Published: September 2021

AbstractOn‐surface Ullmann coupling is an established method for the synthesis of 1D and 2D organic structures. A key limitation to obtaining ordered polymers is the uncertainty in the final structure for coupling via random diffusion of reactants over the substrate, which leads to polymorphism and defects. Here, a topotactic polymerization on Cu(110) in a series of differently‐halogenated para‐phenylenes is identified, where the self‐assembled organometallic (OM) reactants of diiodobenzene couple directly into a single, deterministic product, whereas the other precursors follow a diffusion driven reaction. The topotactic mechanism is the result of the structure of the iodine on Cu(110), which controls the orientation of the OM reactants and intermediates to be the same as the final polymer chains. Temperature‐programmed X‐ray photoelectron spectroscopy and kinetic modeling reflect the differences in the polymerization regimes, and the effects of the OM chain alignments and halogens are disentangled by Nudged Elastic Band calculations. It is found that the repulsion or attraction between chains and halogens drive the polymerization to be either diffusive or topotactic. These results provide detailed insights into on‐surface reaction mechanisms and prove the possibility of harnessing topotactic reactions in surface‐confined Ullmann polymerization.
Design thinking and creativity of colocated versus globally distributed software developers
Authors: Jolak Rodi , Wortmann Andreas , Liebel Grischa , Umuhoza Eric , Chaudron Michel R. V. 
Published: September 2021

AbstractDesigning software is an activity in which software developers think and make design decisions that shape the structure and behavior of software products. Designing software is one of the least understood software engineering activities. In a collaborative design setting, various types of distances can lead to challenges and effects that potentially affect how software is designed. To contribute to a better understanding of collaborative software design, we investigate how communication gaps caused by social and geographic distances affect its design thinking and the creativity of its discussions. To this end, we conducted a multiple‐case study exploring the design thinking and creativity of colocated and distributed software developers in a collaborative design setting. Compared with colocated developers, distributed developers spend less time on exploring the problem space, which could be related to different sociotechnical challenges, such as lack of awareness and common understanding. Distributed development does not seem to affect the creativity of their activities. Developers engaging in collaborative design need to be aware that problem space exploration is reduced in a distributed setting. Unless distributed teams take compensatory measures, this could adversely affect the development. Regarding the effect distance has on creativity, our results are inconclusive and further studies are needed.
Integrative taxonomy of the Selaginella helvetica group based on morphological, molecular and ecological data
Authors: Zhang Meng‐Hua , Wei Ran , Xiang Qiao‐Ping , Ebihara Atsushi , Zhang Xian‐Chun 
Published: September 2021

AbstractThe Eurasian and Mediterranean Selaginella helvetica group is one of the taxonomically challenging groups in the cosmopolitan lycophyte genus Selaginella. Species of the S. helvetica group are all small plants with lax strobili composed of more or less isomorphic sporophylls (isosporophylls) that are basically non‐resupinate. Owing to the similar and minute morphological characteristics, the inapplicability of chloroplast DNA markers for species delimitation and the lack of range‐wide sampling, no comprehensive study has been conducted on these species so far. In this study, we performed phylogenetic analyses based on population‐scale sampling of 126 individuals, covering the entire geographical distribution and morphological variation of this group. Five chloroplast (rbcL, psbA, atpI, atpF, atpF‐H) and two nuclear DNA regions (26S rDNA, pgiC) were used to explore species diversity of this group. The phylogeny inferred from nuclear DNA datasets revealed nine well‐supported monophyletic groups, which provided important evidence for species delimitation and called for taxonomic revision of some taxa. However, in the chloroplast phylogeny, individuals of only three species (S. denticulata, S. helvetica, S. tamamontana) formed monophyletic groups, respectively. We further investigated genome size for each species by flow cytometry and evaluated 21 morphological characteristics of 79 herbarium specimens. MaxEnt analysis was performed to predict the potential suitable distribution of each species. As a result of total evidence, 10 taxa were recognized in the S. helvetica group. The delimitation of S. denticulata, S. laxistrobila, S. nipponica, S. pallidissima, S. prostrata, and S. tamamontana was congruent with previous taxonomical treatments. We reinstated S. shensiensis as an independent species and treated S. longistrobilina as its synonym. Selaginella helvetica (s.str.) is confined to Europe and North Asia, former records of it from the Himalaya‐Hengduan mountains represent an independent species (S. jiulongensis comb. nov.). The nuclear pgiC phylogeny and flow cytometry evidence indicated that S. pseudonipponica is an allotetraploid with S. shensiensis and S. nipponica as its parents. Our results highlight that nuclear DNA markers rather than chloroplast DNA markers are more informative in delimitation of closely related species in Selaginella.
Effectiveness of PPI treatment and guideline adherence in 236 patients with eosinophilic oesophagitis—Results from the population‐based DanEoE cohort shows a low complication rate
Authors: Frandsen Line Tegtmeier , Westmark Signe , Melgaard Dorte , Krarup Anne Lund 
Published: September 2021

AbstractBackgroundProton pump inhibitors (PPIs) are often the first drug of choice in the treatment of eosinophilic oesophagitis (EoE), and in Denmark 8 weeks of high‐dose PPI therapy is recommended as first‐line treatment followed by rebiopsying, reflecting international recommendations.AimsTo assess the population‐based effectiveness of PPIs in the treatment of EoE and evaluate whether patients were treated and followed according to the regional guideline.MethodsThis is a retrospective, registry‐based, DanEoE cohort study of 236 adult EoE patients diagnosed between 2007 and 2017 in the North Denmark Region. After patient file revision, the EoE diagnosis was defined according to the AGREE 2 consensus. Symptomatic PPI response was defined as complete symptom resolution and histological remission (<15 eosinophils per high‐power field).ResultsPPI treatment was initiated in 92% of the EoE patients. High‐ and low‐dose PPIs were prescribed in 55% and 45% of the cases, respectively. When treated with high‐dose PPIs, 68% of the patients were completely symptom‐free, and 49% were in histological remission. In 39% of high‐dose PPI‐treated patients, the symptomatic and histological responses were conflicting. While treated with PPIs, complications were rare, with <5% strictures in responders and <10% in non‐responders. Rebiopsying was done in 67% of the EoE patients started on PPIs.ConclusionsHigh‐dose PPI treatment was effective in half of the EoE patients started on PPIs, but conflicting symptomatic and histological PPI responses were common. Complications were rare when PPIs were started. One‐third of the patients were not rebiopsied as recommended.