bluuebunny/crossref_metadata_2025_split huggingface dataset:
Voltammetric Determination of Trace Heavy Metals by Sequential‐injection Analysis at Plastic Fluidic Chips with Integrated Carbon Fiber‐based Electrodes
Authors: Partheni Vrysiida , Svarnias Konstantinos , Economou Anastasios , Kokkinos Christos , Fielden Peter R. , Baldock Sara J. , Goddard Nicholas J. 
Published: May 2021

AbstractThis work describes a sequential injection analysis (SIA) method for on‐line strippping voltammetric determination of Pb(II), Cd(II) and Zn(II) using an injection‐moulded electrochemical fluidic chip consisting of 3 conductive carbon fiber‐loaded polymer electrodes embedded in a plastic fluidic holder. The sample containing the target metals and a solution containing Bi(III) were aspirated in the holding coil of the SIA manifold. Then, the flow was reversed and the two solutions were directed to the fluidic cell through a mixing coil which induced mixing of the two zones. Upon reaching the cell, simultaneous reduction of the target metals and Bi(III) occurred resulting in the formation of a metal‐Bi alloy on the working electrode. Finally, the accumulated metals were stripped off the bismuth‐film electrode via a positive potential scan and the oxidation current was recorded. The experimental variables (concentration of the bismuth plating solution, deposition potential, sample volume, stripping mode) were investigated and the potential interferences were assessed. The limits of quantification were 2.8 μg L−1 for Pb(II), 3.6 μg L−1 for Cd(II) and 4.2 μg L−1 for Zn(II) and the the within‐chip and between‐chip % relative standard deviations were ≤6.3 % and ≤14 %, respectively. Finally, the sensor was applied to the determination of trace metals in a fish food sample.
Elucidating the effects of silicon carbide sludge and waste glass fiber on the characteristics of porous eco‐fireproof materials
Authors: Lo Kang‐Wei , Lin Kae‐Long , Cheng Ta‐Wui , Lin Ya‐Wen 
Published: May 2021

AbstractThis study used silicon carbide sludge (SCS) and waste glass fiber (WGF) to prepare SCS/WGF porous (SWP) eco‐fireproof materials by a hydrogen peroxide foaming agent. The results showed that the compressive strength of samples that were cured for 1 day and had an SCS replacement level of 10% and added amounts of WGF of 0.5% and 2.0% were 0.32 and 0.46 MPa, respectively. Additionally, it was observed that the stress–strain curves were relatively extended. WGF could improve the geopolymeric matrix of the composites in terms of formation and/or redistribution of cracks by bridging cracks and perforations within the matrix. When the added amounts of WGF were 0.5% and 2.0%, the reverse‐side temperatures of the samples were 238 and 262°C, respectively, which showed that adding an appropriate amount of WGF could effectively reduce the reverse‐side temperature of SWP eco‐fireproof materials. The results displayed the beneficial influence of SCS and WGF in improving bulking density, compressive strength, and flexural strength and in reducing porosity and thermal conductivity. Therefore, the results showed that SWP eco‐fireproof materials reinforced using SCS and WGF have potential as building materials.
Bald eagle search optimization on dual fueled reactivity controlled combustion ignition based engine characteristics by altering low reactive fuels
Authors: Gokul Karthik Arunachalam , Saravanakumar Rajagopalan , Vijayakumar Palanivel 
Published: May 2021

AbstractIn conventional diesel engines, the reactivity controlled combustion ignition (RCCI) systems find to be offer better emission and engine performances. The main aim of this work is to study and enhance the emission, combustion, and performance characteristics of the RCCI based diesel engine. In the present work, we compare and optimize the characteristics of the diesel engines when using methane added hydrogen and methanol fuels as low reactive fuels (LRF). The diesel and dimethyl ether added biodiesel (spirulina microalgae) are used as high reactivity fuels (HRF) with six different proportion rates. In this, initially, the experimental results are investigated by using methanol as LRF with HRF fuel, and better blend proportion is optimized by using bald eagle search optimization (BESO) performed in the Matlab platform. Then, the methane content added hydrogen is used as LRF with the optimized HRF fuel combinations. Finally, from both cases, the optimized experimental characteristics are predicted with the help of the Elman recurrent neural network based BESO. In which, the hydrogen gas contributed RCCI engine provide supreme engine characteristics such as 217.6 g/kWh of specific fuel consumption, 38.7% of brake thermal efficiency, 84.45 bar of cylinder pressure, and the CO2 and NOx emissions are 539.2 g/kWh, and 1020 ppm. The result reveals that the proposed predicted results are superiorly validated the experimental outcomes with minimal errors.
Raw material choices and material characterization of the 3rd and 2nd millennium BC pottery from the Petit‐Chasseur necropolis: Insights into the megalith‐erecting society of the Upper Rhône Valley, Switzerland
Authors: Carloni Delia , Šegvić Branimir , Sartori Mario , Zanoni Giovanni , Moscariello Andrea , Besse Marie 
Published: May 2021

AbstractOwing to its well‐preserved and long‐lasting archaeological record, the necropolis of Petit‐Chasseur in the Upper Rhône Valley (3100–1600 BC) showcases the economic, social, and ideological changes of 3rd and 2nd millennium BC Europe excellently. An in‐depth investigation of pottery artifacts was carried out using multiple spectroscopic and microscopic techniques. Nine types of ceramic fabrics were identified based on the variety of temper and natural inclusions; however, the mineralogy and phase chemistry of the ceramic matrix showed the paste to be primarily illitic or muscovitic, irrespective of the inclusion type. Muscovitic clays were likely procured from the fluvioglacial, glaciolacustrine, colluvial, and till sediment abundantly available at higher altitudes of the Upper Rhône Valley, whereas illitic clays were acquired from pedogenized loess horizons or the Rhône River alluvium. Different raw material choices and paste preparation practices suggest distinct ceramic traditions that likely existed in the valley during the 3rd and 2nd millennia BC. This, along with the hypothesized provenance of the raw material, is likely in favor of various prehistoric communities gathering at the megalithic necropolis from close and distant parts of the valley using the Petit‐Chasseur site as a place of assembly.
Entwicklung eines Python‐Skripts zur Festigkeitsreduktion mit numerischen Methoden
Authors: Jürgens Hauke , Henke Sascha 
Published: May 2021

AbstractDie Anwendung numerischer Methoden beschränkt sich in der Geotechnik derzeit zumeist auf die Prognose des Verformungsverhaltens von Bauwerken im Grenzzustand der Gebrauchstauglichkeit. Der Grenzzustand der Tragfähigkeit wird unter Berücksichtigung numerischer Methoden, z. B. der Finite‐Elemente‐Methode bisher nur in Ansätzen (z. B. bei homogenen Böschungen und kombinierter Pfahl‐Plattengründung) behandelt. In dem vorliegenden Beitrag wird daher die Grundlage für die Anwendung einer ganzheitlichen Methode zur parallelen Festigkeitsreduktion an Strukturelementen und einer Abminderung der Scherparameter des Bodens diskutiert.In einer ersten Parameterstudie wird ein auf der Programmiersprache Python basierendes Skript zur Reduktion der Scherparameter des Bodens durch einen Abgleich mit anerkannten Methoden zur Berechnung der Standsicherheit von Böschungen verifiziert. Anschließend werden die Anwendungsmöglichkeiten des Python‐Skripts so erweitert, dass in einer zweiten Parameterstudie die Festigkeitsparameter von Strukturelementen innerhalb einer stabilitätsgefährdeten Böschung reduziert werden können. Auf Grundlage dessen erfolgt eine Beurteilung über den wahrscheinlichen ersten Versagensmechanismus (Boden‐ oder Strukturversagen). Zum Abschluss werden die Ergebnisse der beiden Parameterstudien unter Berücksichtigung einer numerischen Nachweisführung in einen kausalen Kontext gebracht und zukünftige Forschungsansätze diskutiert.
Plant parasitic nematodes, substrates or grass species as reasons for poor reestablishment of a sand‐based putting green after winter kill
Authors: Xiao Kemeng , Hesselsøe Karin Juul , Magnusson Christer , Espevig Tatsiana , Pettersen Trond , Aamlid Trygve S. 
Published: May 2021

AbstractIn 2018–2019, establishment problems were encountered, after reseeding creeping bentgrass (Agrostis stolonifera) on a sand‐based putting green after ice encasement at the NIBIO Turfgrass Research Center, Norway. Seeds germinated, but the seedlings attained a purple color and died in large patches. Replacement of the top 3 cm layer with new sand amended with Sphagnum peat or garden compost did not solve the problem. To explain this phenomenon, we (1) analyzed the original substrate for nematodes in patches with and without reestablishment failure; and (2) conducted a factorial pot trial with creeping bentgrass and Chewings fescue (Festuca rubra ssp. commutata) seeded on different substrates, some of them in layers, and with and without phosphorus (P) fertilization. The nematode counts showed six times more stubby‐root nematodes and two times more spiral nematodes and needle nematodes in the patches with dead seedlings than in the patches with healthy seedings. In the pot trial, the fastest and slowest reestablishment was observed with new sand amended with garden compost and in the two treatments that included the original substrate, respectively. Replacement of the top 3 cm of the old substrate with new garden compost resulted in stagnation of bentgrass seedlings from four weeks after seeding, while fescue seedlings were unaffected. We conclude that the failure to reestablish creeping bentgrass was primarily due to nematodes, which are likely to be more critical for seedlings than for established turf. The green was later reestablished successfully with a 100 % red fescue seed blend.
Electrical therapies act on the Ca2+/CaM signaling pathway to enhance bone regeneration with bioactive glass [S53P4] and allogeneic grafts
Authors: Bagne Leonardo , Oliveira Maraiara A. , Pereira Amanda T. , Caetano Guilherme F. , Oliveira Camila A. , Aro Andréa A. , Chiarotto Gabriela B. , Santos Glaucia M. T. , Mendonça Fernanda A. S. , Santamaria‐Jr Milton 
Published: May 2021

AbstractThis study aimed to investigate the application of low‐intensity electrostimulation (ES) and electromagnetic stimulation (EM) associated with bioactive glass (BG) or allogeneic grafts (BB) in bone regeneration. A cell viability test on osteoblasts (UMR‐106) was performed in the presence of BB and BG grafts associated with ES (10 μA/5 min) and EM (500 Hz/2 min). Critical defects (25 mm2) in calvaria were generated in male Wistar rats, and bone regeneration was evaluated on the 30th, 60th, and 120th days after surgery. Cell proliferation increased with the application of ES in both grafts and after EM with BG. Bone remodeling was more effective using the allogeneic graft in both therapies, with increased angiogenesis, osteoblast proliferation, and OPN expression in the BB + EM group. A higher number of osteoblasts and osteoclasts, and an increase in bone sialoprotein, Runx‐2, and Opn gene expression were found in the BB + ES group. The BG graft associated with EM therapy had an increased proliferation of osteoblasts and increased expression of Runx‐2 and Opn. Groups that had BG and ES therapy had increased numbers of osteoblasts, osteoclasts, and increased OPN expression. The expression of voltage‐gated calcium channels increased in groups with ES, while calmodulin expression increased in therapies without grafting. ES and EM therapies favored the repair of bone defects upon grafting by improving angiogenesis, osteogenic gene expression, and tissue reorganization. Despite activating different pathways, both therapies increased the intracellular concentrations of calmodulin, leading to cell proliferation and bone regeneration.
Image repair during a U.S. Securities and Exchange Commission investigation
Authors: Demaline Christopher J. 
Published: May 2021

AbstractThis paper examines management's image repair strategies present in disclosures noting a firm's involvement in an SEC investigation. This empirical analysis employs a systematic content analysis of managements' 10‐K disclosures released from 2010 through 2019. The sample is drawn from firms identified in SEC accounting and auditing enforcement releases. This research suggests that management's disclosure concerning an SEC investigation commonly focuses on adding positive information to the disclosure (bolstering) and discussing plans to solve the problem. Managers commonly employ multiple image repair tactics within the same 10‐K. These findings have key implications for financial reporting regulators and accounting standards setters concerned with understanding how managers may manipulate disclosures. Investors may also be interested in understanding how company managers attempt to restore the firm's reputation when the firm is undergoing regulatory scrutiny. Further, the findings of this study enhance the knowledge of corporate image restoration strategy. This paper is the first to focus on managements’ use of image repair disclosure strategies when a securities regulator is investigating the firm.
Hybrid localized graph kernel for machine learning energy‐related properties of molecules and solids
Authors: Casier Bastien , Chagas da Silva Mauricio , Badawi Michael , Pascale Fabien , Bučko Tomáš , Lebègue Sébastien , Rocca Dario 
Published: May 2021

AbstractNowadays, the coupling of electronic structure and machine learning techniques serves as a powerful tool to predict chemical and physical properties of a broad range of systems. With the aim of improving the accuracy of predictions, a large number of representations for molecules and solids for machine learning applications has been developed. In this work we propose a novel descriptor based on the notion of molecular graph. While graphs are largely employed in classification problems in cheminformatics or bioinformatics, they are not often used in regression problem, especially of energy‐related properties. Our method is based on a local decomposition of atomic environments and on the hybridization of two kernel functions: a graph kernel contribution that describes the chemical pattern and a Coulomb label contribution that encodes finer details of the local geometry. The accuracy of this new kernel method in energy predictions of molecular and condensed phase systems is demonstrated by considering the popular QM7 and BA10 datasets. These examples show that the hybrid localized graph kernel outperforms traditional approaches such as, for example, the smooth overlap of atomic positions and the Coulomb matrices.
Solar activity modulates the El Niño‐Southern Oscillation‐induced precipitation anomalies over southern China in early spring
Authors: Ma Hedi , Wang Ruili , Lai Anwei , Li Xing , Wang Feiyang , Zhou Zhimin , Li Xiao 
Published: May 2021

AbstractThe present study identifies an evident solar cycle modulation upon the spatial pattern of the El Niño‐Southern Oscillation (ENSO) impact on the southern China precipitation in early spring (February–March). During high/low solar activity (HS/LS) years, the significant positive correlation between the wintertime Niño 3.4 index and the precipitation in the following early spring mainly locates at the southeastern China/Yangtze River Valley (SEC/YRV). Our analysis also suggests that the precipitation anomalies show asymmetries between ENSO warm and cold events under both solar phases. In HS years, the ENSO warm events‐related rainfall anomalies over the southern China are weak, but during the ENSO cold events significant dry anomalies appear at the SEC region. In LS years, significant wet anomalies over the YRV region are found during the ENSO warm events, whilst the rainfall anomalies are insignificant for the ENSO cold events. These modulations on precipitation are mediated by the changes in the ENSO‐associated anomalous western North Pacific anticyclone/cyclone, which may be attributed to the solar modulations on the ENSO‐associated sea surface temperature anomalies. Our results highlight that the level of solar activity should be taken into account when ENSO is used as a predictor for the precipitation over East Asia. [Correction added on 18 June 2021, after first online publication: The text for the abstract and graphical abstract were interchanged in the original‐published article. This updated version rectifies the error.]
Distinguishing zooplankton fecal pellets as a component of the biological pump using compound‐specific isotope analysis of amino acids
Authors: Doherty Shannon C. , Maas Amy E. , Steinberg Deborah K. , Popp Brian N. , Close Hilary G. 
Published: May 2021

AbstractZooplankton contribute a major component of the vertical flux of particulate organic matter to the ocean interior by packaging consumed food and waste into large, dense fecal pellets that sink quickly. Existing methods for quantifying the contribution of fecal pellets to particulate organic matter use either visual identification or lipid biomarkers, but these methods may exclude fecal material that is not morphologically distinct, or may include zooplankton carcasses in addition to fecal pellets. Based on results from seven pairs of wild‐caught zooplankton and their fecal pellets, we assess the ability of compound‐specific isotope analysis of amino acids (CSIA‐AA) to chemically distinguish fecal pellets as an end‐member material within particulate organic matter. Nitrogen CSIA‐AA is an improvement on previous uses of bulk stable isotope ratios, which cannot distinguish between differences in baseline isotope ratios and fractionation due to metabolic processing. We suggest that the relative trophic position of zooplankton and their fecal pellets, as calculated using CSIA‐AA, can provide a metric for estimating the dietary absorption efficiency of zooplankton. Using this metric, the zooplankton examined here had widely ranging dietary absorption efficiencies, where lower dietary absorption may equate to higher proportions of fecal packaging of undigested material. The nitrogen isotope ratios of threonine and alanine statistically distinguished the zooplankton fecal pellets from literature‐derived examples of phytoplankton, zooplankton biomass, and microbially degraded organic matter. We suggest that δ15N values of threonine and alanine could be used in mixing models to quantify the contribution of fecal pellets to particulate organic matter.
On‐Demand Coherent Perfect Absorption in Complex Scattering Systems: Time Delay Divergence and Enhanced Sensitivity to Perturbations
Authors: del Hougne Philipp , Yeo K. Brahima , Besnier Philippe , Davy Matthieu 
Published: May 2021

AbstractNon‐Hermitian photonic systems capable of perfectly absorbing incident radiation recently attracted much attention both because fundamentally they correspond to an exotic scattering phenomenon (real‐valued scattering matrix zero) and because their extreme sensitivity holds great technological promise. The sharp reflection dip is a hallmark feature underlying many envisioned applications in precision sensing, secure communication, and wave filtering. However, a rigorous link between the underlying scattering anomaly and the system's sensitivity to a perturbation is still missing. Here, a theoretical description in complex scattering systems is developed which quantitatively explains the reflection dip's shape. It is furthermore demonstrated that coherent perfect absorption (CPA) is associated with a phase singularity and that the sign of the diverging time delay is related to the mismatch between excitation rate and intrinsic decay rate. The theoretical predictions are confirmed in experiments based on a 3D chaotic cavity excited by eight channels. Rather than relying on operation frequency and attenuation inside the system to be two free parameters, “on‐demand” CPA is achieved at an arbitrary frequency by tweaking the chaotic cavity's scattering properties with programmable meta‐atom inclusions. Finally, the optimal sensitivity of the CPA condition to minute perturbations of the system is proven theoretically and verified experimentally.
Polymer‐Based Drug‐Free Therapeutics for Anticancer, Anti‐Inflammatory, and Antibacterial Treatment
Authors: Tavares Marina Rodrigues , Pechar Michal , Chytil Petr , Etrych Tomáš 
Published: May 2021

AbstractThis paper summarizes the area of biomedicinal polymers, which serve as nanomedicines even though they do not contain any anticancer or antiinflammatory drugs. These polymer nanomedicines with unique design are in the literature highlighted as a novel class of therapeutics called “drug‐free macromolecular therapeutics.” Their therapeutic efficacy is based on the tailored multiple presentations of biologically active vectors, i.e., peptides, oligopeptides, or oligosaccharides. Thus, they enable, for example, to directly induce the apoptosis of malignant cells by the crosslinking of surface slowly internalizing receptors, or to deplete the efficacy of tumor‐associated proteins. The precise biorecognition of natural binding motifs by multiple vectors on the polymer construct remains the crucial part in the designing of these drug‐free nanomedicines. Here, the rationales, designs, synthetic approaches, and therapeutic potential of drug‐free macromolecular therapeutics consisting of various active vectors are described in detail. Recent developments and achievements for namely B‐cell lymphoma treatment, Gal‐3‐positive tumors, inflammative liver injury, and bacterial treatment are reviewed and highlighted. Finally, a possible future prospect within this highly exciting new field of nanomedicine research is presented.
Patients with Cervical Dystonia Demonstrated Decreased Cognitive Abilities and Visual Planning Compared to Controls
Authors: Bastos Marina S.C. , Nickel Renato , Camargo Carlos H.F. , Teive Hélio A.G. 
Published: May 2021

ABSTRACTBackgroundCervical dystonia (CD) involves clinical and motor manifestations, and visual and cognitive dysfunctions may also be frequent.ObjectiveTo evaluate functional vision, visual attention, and cognitive aspects in patients with CD compared with a control group.MethodsFifty patients with CD were assessed using the Useful Field of View Test (UFOV), the Mini Mental State Examination (MMSE), and the Trail Making Tests (TMT‐A and TMT‐B), and compared with an identical number of health controls matched by sex, age, and educational level.ResultsNo differences were seen between the groups in terms of MMSE score (P = 0.481), but the CD patient group had poorer scores for the TMA‐A (P = 0.004) and TMT‐B (P = 0.004). For the UFOV subtests, a decrease was found for visual processing speed (P < 0.001), divided attention (P < 0.001), and selective attention (P = 0.001), as well as higher frequency in the categories with higher risk index in the UFOV test (P < 0.001).ConclusionPatients with CD may exhibit decreased functional vision and visual attention, as well as higher risk in performing complex activities.