bluuebunny/crossref_metadata_2025_split huggingface dataset:
Arrested Substrate Binding Resolves Catalytic Intermediates in Higher‐Plant Water Oxidation
Authors: Zahariou Georgia , Ioannidis Nikolaos , Sanakis Yiannis , Pantazis Dimitrios A. 
Published: October 2020

AbstractAmong the intermediate catalytic steps of the water‐oxidizing Mn4CaO5 cluster of photosystem II (PSII), the final metastable S3 state is critically important because it binds one substrate and precedes O2 evolution. Herein, we combine X‐ and Q‐band EPR experiments on native and methanol‐treated PSII of Spinacia oleracea and show that methanol‐treated PSII preparations of the S3 state correspond to a previously uncharacterized high‐spin (S=6) species. This is confirmed as a major component also in intact photosynthetic membranes, coexisting with the previously known intermediate‐spin conformation (S=3). The high‐spin intermediate is assigned to a water‐unbound form, with a MnIV3 subunit interacting ferromagnetically via anisotropic exchange with a coordinatively unsaturated MnIV ion. These results resolve and define the structural heterogeneity of the S3 state, providing constraints on the S3 to S4 transition, on substrate identity and delivery pathways, and on the mechanism of O−O bond formation.
Diels–Alder Polymer Networks with Temperature‐Reversible Cross‐Linking‐Induced Emission
Authors: Jiang Yu , Hadjichristidis Nikos 
Published: October 2020

AbstractA novel synthetic strategy gives reversible cross‐linked polymeric materials with tunable fluorescence properties. Dimaleimide‐substituted tetraphenylethene (TPE‐2MI), which is non‐emissive owing to the photo‐induced electron transfer (PET) between maleimide (MI) and tetraphenylethene (TPE) groups, was used to cross‐link random copolymers of methyl (MM), decyl (DM) or lauryl (LM) methacrylate with furfuryl methacrylate (FM). The mixture of copolymer and TPE‐2MI in DMF showed reversible fluorescence with “on/off” behavior depending on the Diels–Alder (DA)/retro‐DA process, which is easily adjusted by temperature. At high temperatures, the retro‐DA reaction is dominant, and the fluorescence is quenched by the photo‐induced electron transfer (PET) mechanism. In contrast, at low temperatures, the emission recovers as the DA reaction takes over. A transparent PMFM/TPE‐2MI polymer film was prepared which shows an accurate response to the external temperature and exhibited tunable fluorescent “turn on/off” behavior. These results suggest the possible application in areas including information security and transmission. An example of invisible/visible writing is given.
Selection of Natural Extracts for their Antioxidant Capacity by Using a Combination of In Vitro Assays
Authors: Deyrieux Charlotte , Durand Erwann , Guillou Sonia , Barouh Nathalie , Baréa Bruno , Michel Salaun Françoise , Villeneuve Pierre 
Published: October 2020

AbstractNumerous different in vitro assays, labeled as “antioxidant assays,” are used intensively to predict the antioxidant capacity of phenolic compounds. Most of these methods give valuable information in terms of chemical reactivities but also present some weaknesses. It may be difficult to use them to predict antioxidant capacity in real conditions. Indeed, lipid oxidation is a complex reaction, with numerous paths and components, and antioxidant action can occur via a multitude of mechanisms, especially when different phases coexist in the lipid‐based formulation. Yet, correctly combining selected in vitro methods to extract complementary information with respect to antioxidant behaviors would be much better and will help reducing the gap between prediction and efficacy in the finished product. Thus, we hereby propose a methodology to evaluate the antioxidant properties of 12 selected natural polyphenolic extracts based on the appropriate combination of in vitro assays. The scores obtained with the DPPH test, the measure of the chelation capacity, the evaluation of antioxidants efficiency in emulsions (CAT and VESICAT assays), or in bulk oils were submitted to a statistical treatment. This analysis allowed a ranking on their global antioxidant capacities and the creation of clusters depending on their mechanisms of action and the type of media where the tests were performed.
High efficient corrosion inhibitor of water‐soluble polypyrrole–sulfonated melamine formaldehyde nanocomposites for 316 L stainless steel
Authors: Muthusamy Packiaraj , Konda Kannan Satheesh Kumar 
Published: October 2020

AbstractIn this work, new water‐soluble polypyrrole–sulfonated melamine formaldehyde nanocomposites (PPy–SMF NCs) were first synthesized by one‐step in‐situ polymerization of pyrrole with FeCl3 in the presence of various mole ratios of sulfonated melamine formaldehyde (SMF). The characterization of the PPy–SMF NCs was investigated via ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X‐ray, dynamic light scattering, transmission electron microscopy, X‐ray diffraction, thermogravimetric analysis, differential scanning calorimetry, and conductivity measurements. The resulting PPy–SMF NCs were proved to improve the solubility, electrical properties, and thermal stability. The anti‐corrosion performance of PPy‐SMF NCs on 316 L stainless steel (316 L SS) was examined using electrochemical impedance spectroscopy, potentiodynamic polarization, and weight‐loss method. The result showed that the PPy–SMF NCs acts as a mixed‐type inhibitor, as well as a protective layer to 316 L SS against corrosion in 3.5% NaCl solution. The Langmuir adsorption isotherm was well fitted and suitable to explain the adsorption behavior of the PPy‐SMF NCs on 316 L SS surface. The inhibition efficiency of PPy‐SMF NCs is 99% by the weight‐loss method which could be attributed to the protective layer formed on 316 L SS surface by the adsorption of PPy‐SMF NCs.
Self‐assembly and sol‐to‐gel transition of thermosensitive methoxy‐polyethylene glycol‐polyalanine block copolymer hydrogels
Authors: Ma Wei‐Chun , Chu I‐Ming 
Published: October 2020

AbstractCertain amphiphilic polymers can self‐assemble to form various structures, such as micelles and hydrogels in aqueous medium, depending on the concentration or temperature. These different structures have found many applications in biomedical and material processing fields. The assembly processes of the polypeptide‐containing diblock copolymer, methoxy poly(ethylene glycol)‐block‐poly(L‐alanine) (mPEG‐PA), was studied to elucidate the relationship between different structures with parameters such as chain lengths (volume fraction) of the two blocks, molecular weights, medium polarity, temperature, and concentration. Gelation mechanism was especially focused in the study. Various solution‐cast morphologies observed by scanning electron microscopy (SEM) imaging including cylinders and micelles aggregates can be obtained by using solvents with different polarity for casting with simply tuning the chain lengths. The sol‐to‐gel transition mechanism can be best explained by phase separation between polymer‐rich and water‐rich phases. It might be spinodal decomposition process to cause the phase separation. Furthermore, the branch and flack structures can be observed due to phase separation mechanism and different chain lengths by SEM images. This result offers new insights into behavior of mPEG‐PA system, enabling more controlled manipulation to various applications.
Layer‐by‐layer assembled bagasse to enhance the fire safety of epoxy resin: A renewable environmental friendly flame retardant
Authors: Chen Zhiquan , Jiang Juncheng , Yu Yuan , Chen Gang , Chen Tingting , Zhang Qingwu 
Published: October 2020

AbstractIn an effort to make rational use of resources, wasted bagasse were collected, and then fabricated by layer‐by‐layer (LbL) assembly to prepare an environmentally benign flame retardant for epoxy resin (EP). Six chitosan/ammonum polyphosphate bilayers were successfully deposited on the surface of bagasse, which endows EP/6BL@BF composites with a limiting oxygen index value of 24.1% and V‐1 rating in UL‐94 test. Compared with untreated bagasse, cone calorimetry test reveals that the incorporation of 6BL@BF reduces the peak heat release rate and total heat release by 64.6% and 13.2%, respectively. Besides, expandable graphite (EG) was combined with 6BL@BF to further enhance the fire safety and thermal stability of EP composites. Furthermore, the gas and condensed phase analysis of EP/6BL@BF/EG‐3 composite was investigated by TG‐IR, scanning electronic microscopy, Laser Raman spectroscopy, and X‐ray photoelectron spectroscopy, and the flame retardant mechanism of 6BL@BF/EG was proposed. Finally, the mechanical properties of EP composites were investigated systematically.
Laboratory and field studies for the control of Chagas disease vectors using the fungus Metarhizium anisopliae
Authors: Rangel Drauzio E. N. , Piedrabuena Aquiles E. , Roitman Isaac , Messias Claudio L. 
Published: October 2020

AbstractChagas disease is one of the most important insect‐vectored diseases in Brazil. The entomopathogenic fungus Metarhizium anisopliae was evaluated against nymphs and adults of Panstrongylus megistus, Triatoma infestans, and T. sordida. Pathogenicity tests at saturated humidity demonstrated high susceptibility to fungal infection. The shortest estimates of 50% lethal time (LT50) for P. megistus varied from 4.6 (isolate E9) to 4.8 days (genetically modified strain 157p). For T. infestans, the shortest LT50 was 6.3 (E9) and 7.3 days (157p). For T. sordida, the shortest LT50 was 8.0 days (157p). The lethal concentration sufficient to kill 50% of T. infestans (LC50) was 1.9 × 107 conidia/ml for strain 157p. In three chicken coops that were sprayed with M. anisopliae, nymphs especially were well controlled, with a great population reduction of 38.5% after 17 days. Therefore M. anisopliae performed well, controlling Triatominae in both laboratory and field studies.
Ca‐based bifunctional acid‐basic model‐catalysts for n‐butanol production from ethanol condensation
Authors: Pinzón Marina , Cortés‐Reyes Marina , Herrera Concepcion , Larrubia Maria Á. , Alemany Luis J. 
Published: October 2020

AbstractEthanol to n‐butanol conversion is a process that can increase the carbon number of alcohols by coupling. There is increasing interest in the mechanisms for n‐butanol production in a simple step through the effective use of bifunctional acid–base catalysts. In this context, commercial hydroxyapatite (HAP) and two synthetized model supported catalysts, Ca/Al2O3 and Ca‐P/Al2O3, were used in bioethanol condensation. Characterization and acid–base sites were considered, and Fourier‐transform infrared (FTIR) spectroscopy and diffuse reflectance infrared Fourier‐transform spectroscopy–mass spectrometry (DRIFT‐MS) reactivity tests were performed in situ, as a first approximation to design a sustainable catalytic process rationally, and with the aim of understanding the process at the catalytic surface. The results indicated that the reactions occur at a large range of temperatures (200–450 °C). Hydroxyapatite and Ca/Al2O3 have similar basic sites (low and medium) and Ca‐P/Al2O3 presented the strongest Brönsted and Lewis combined acid sites. Three major reactions were identified: non‐oxidative dehydrogenation, aldol condensation, and intermolecular reduction, associated with the basic‐acid sites Ca‐O‐Ca/Ca‐O‐P/Ca‐O‐Al. Side reactions also occur involving different acid sites related to Lewis alumina centers favoring ethylene or diethyl‐ether production. © 2020 Society of Industrial Chemistry and John Wiley & Sons Ltd
Glucocorticoid receptors and their upstream epigenetic regulators in adults with steroid‐resistant nephrotic syndrome
Authors: Rahbar Saadat Yalda , Hejazian Seyyedeh Mina , Nariman‐Saleh‐Fam Ziba , Bastami Milad , Poursheikhani Arash , M. Shoja Mohammadali , Ardalan Mohammadreza , Zununi Vahed Sepideh 
Published: October 2020

AbstractSteroid‐resistant nephrotic syndrome (SRNS) is a clinical challenge with variable clinical outcomes. In patients with SRNS, unsuccessful anti‐inflammatory and anti‐proteinuric effects of steroids lead to end‐stage renal disease (ESRD). Our objective was to define the expression pattern of the glucocorticoid receptors (GR) α and β and their epigenetic regulators (miR‐24, miR‐30a, and miR‐370) in a group of adults with SRNS. In this regard, sixty primary NS patients with focal segmental glomerulosclerosis (FSGS, N = 30) and membranous glomerulonephritis (MGN, N = 30) and also healthy volunteers (N = 24) were enrolled. Real‐time PCR was performed to evaluate the expression levels of the aforementioned genes in peripheral blood mononuclear cell (PBMC) samples. Furthermore, an in‐silico analysis was performed to understand the signaling pathways and biological procedures that may be targeted by these microRNAs in NS. The decreased and increased levels of GRα and GRβ were not significant, respectively. Statistically significant reduced miR‐24 levels were observed between control/MGN (p = .022) and MGN/FSGS (p = .032) groups. Additionally, a decrease was detected in miR‐30a between MGN and FSGS (p = .049) groups. There was a significant increase in miR‐370 expression level between control and NS groups (p = .029), as well as control/MGN (p = .008), and MGN/FSGS (p = .046). Bioinformatics analysis predicted the possible targets of the studied genes including genes involved in TGF‐β, Notch1, and p53 signaling pathways, regulation of gene expression, intracellular signal transduction, negative regulation of response to the stimulus, cell‐cell signaling, and cell activation in the pathogenesis of SRNS. Taken all together, dysregulated levels of GRα, GRβ were not attributed to SRNS in our patients. It seems that pharmacokinetics and the genetic variations in podocyte‐related genes may be associated with the steroid‐resistance in our adult patients with NS rather than GR expression.
Tumor purity as a prognosis and immunotherapy relevant feature in gastric cancer
Authors: Gong Zhe , Zhang Jieyun , Guo Weijian 
Published: October 2020

AbstractTumor microenvironment (TME) has been illustrated their clinic pathological significance in predicting outcomes and therapeutic efficacy by more and more studies. Tumor purity, which reflects the features of TME, is defined as the proportion of cancer cell in the tumor tissue. However, the current staging and prognostic prediction system in gastric cancer (GC) paid little attention to TME. Therefore, we carried out the study to explore the role of tumor purity in GC. We retrospectively collected the clinical and transcriptomic data from four public data sets (n = 1340), GSE15459, GSE26253, GSE62254, and The Cancer Genome Atlas (TCGA). About 34 GC patients from Fudan University Shanghai Cancer Center (FUSCC) were assigned as an independent validation group. Tumor purity was measured by a computational method. Low tumor purity was associated with unfavorable prognosis, upregulated EMT and stemness pathways, more infiltrating of Tregs, M1 and M2 macrophages and a higher expression level of various immune checkpoints and chemokines recruiting immune suppressive cells. Our study indicates low tumor purity in GC was associated with unfavorable prognosis and immune‐evasion phenotype. Further investigations toward tumor purity in GC may contribute to prognosis prediction and the decision of therapy strategies.
Driving Towards Highly Selective and Coking‐Resistant Natural Gas Reforming Through a Hybrid Oxygen Carrier Design
Authors: Qin Lang , Chen Yu‐Yen , Guo Mengqing , Liu Yan , A. Fan Jonathan , Fan Liang‐Shih 
Published: October 2020

AbstractCarbon deposition can be promoted by catalyst‐assisted C−H bond dissociation, which is one of the most concerning issues in reaction engineering. Treatment of carbon contamination inevitably generates CO2 which has a detrimental effect on the environment. Consequently, the development of efficient oxygen carriers is important to commercial viability of chemical looping processes. In this work, density functional theory (DFT) calculations were conducted and reveal that carbon deposition is a cascade reaction of accumulative C−C bond forming that deactivates LFO surface due to gradual accumulation of lattice oxygen vacancies. Guided by DFT mechanistic predictions, we tailor catalytic reactive perovskite LaFeO3 (LFO) with high oxygen carrying hematite Fe2O3 (FO) into a hybrid oxygen carrier LFO‐FO. The LFO‐FO oxygen carrier exhibits excellent carbon inhibition capability and high reactivity with syngas selectivity above 98 %. This work proposes a promising strategy toward oxygen carrier development with low cost, high reactivity, and selectivity for chemical looping technology.
Comparison of Voxel‐Based and Mesh‐Based CFD Models for Aerosol Deposition on Complex Fibrous Filters
Authors: Hoch Dennis , Azimian Mehdi , Baumann André , Behringer Jens , Niessner Jennifer 
Published: October 2020

AbstractAerosols represent a health risk since small droplets may enter the respiratory system and cause lung cancer, allergies, or diseases like COVID‐19. In this work, an Eulerian‐Lagrangian computational fluid dynamics model is used based on a voxel‐based (GeoDict) and a mesh‐based (StarCCM+) code. For evaluating accuracy and computational time of both models, fractional filtration efficiency and pressure drop are compared to an empirical solution for a single fiber and to experimental results for a complex 3D fibrous filter material. Simulation results of both methods are in good agreement with empirical and measurement results although the complex geometry of the fibers is captured more accurately by the unstructured mesh using the same resolution. Computing times are much faster using the voxel‐based code.
Dynamic Modeling of Electrochemical pH‐Swing Extraction
Authors: Gausmann Marcel , Jupke Andreas 
Published: October 2020

AbstractElectrochemical unit operations have the potential to enable zero‐waste downstream processing of bio‐based products. A profound understanding of the underlying phenomena is inevitable for technological development. This work presents a dynamic model for the electrochemical pH‐swing extraction on the example of succinic acid. Model results are well in line with experimental data. In addition, dynamic modeling enables the examination of mass transport kinetics and provides insights into the interactions between aqueous pH‐ and liquid‐liquid extraction equilibria.
Entwicklung einer Methode zur nichtinvasiven Messung des Absolutdrucks in teiltransparenten Gebinden mit karbonisierten Getränken
Authors: Grafen Markus , Falkenstein Martin , Ostendorf Andreas , Esen Cemal 
Published: October 2020

AbstractEs wird eine nichtinvasive optische Messtechnik für die Lebensmittelanalytik vorgestellt, die eine zuverlässige Bestimmung des Absolutdrucks in Getränkeflaschen mit karbonisiertem Inhalt ermöglicht. Die Messtechnik nutzt eine durchstimmbare Laserdiode mit einer Emissionswellenlänge um 2004 nm für die Aufzeichnung von drei bis vier Absorptionslinien von CO2 und wertet die zum Absolutdruck proportionale Druckverbreiterung der Linien aus. Mit der entwickelten Messmethode konnte bei Feldmessungen an versiegelten Softdrinkflaschen aus PET schließlich eine Standardabweichung wiederholter Absolutdruckmessungen bis 5,5 bar von unter 50 mbar erreicht werden.
ThyroSeq v3 for Bethesda III and IV: An institutional experience
Authors: Desai Dimpi , Lepe Marcos , Baloch Zubair Wahid , Mandel Susan J. 
Published: October 2020

BackgroundThe ThyroSeq v3 genomic classifier is a commercial molecular test that examines a wide spectrum of genomic alterations in a thyroid fine‐needle aspiration (FNA) sample and reports test results as either negative or positive. The authors report their institutional experience with ThyroSeq v3.MethodsThyroid FNA specimens diagnosed as either atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) (Bethesda category III [Bethesda III] according to The Bethesda System for Reporting Thyroid Cytopathology) or follicular neoplasm/suspicious for follicular neoplasm (FN/SFN) (Bethesda IV) that had ThyroSeq v3 results available from December 2017 through October 2019 were retrieved for analysis. FNA diagnoses were correlated with ThyroSeq v3 results and follow‐up histopathology.ResultsIn total, 415 cases (AUS/FLUS, n = 251; FN/SFN, n = 164) were retrieved: 294 (71%) were reported as ThyroSeq v3‐negative, and 121 (29%) were reported as ThyroSeq v3‐positive. The benign call rate (BCR) of ThyroSeq v3 for AUS/FLUS (82%; 206 of 251 cases) was significantly higher (P < .001) than that for FN/SFN (BCR, 54%; 88 of 164 cases). Histopathologic follow‐up was available for 127 cases (ThyroSeq v3‐positive, 96; ThyroSeq v3‐negative, 31), of which 57 were benign and 70 were malignant (including noninvasive follicular thyroid neoplasm with papillary‐like nuclear features). The negative predictive value of ThyroSeq v3 was significantly higher for AUS/FLUS (99.5%) than for FN/SFN (95.4%; P < .0294), given malignancy rates of 10% for AUS/FLUS and 30% for FN/SFN. Forty‐five unique combinations of genetic alterations were detected in the operated ThyroSeq‐positive cases, and there were only 5 false‐negative cases, comprised of 4 low‐risk neoplasms.ConclusionsThe high BCR of ThyroSeq v3 for AUS/FLUS prevents surgery in a majority of patients. The ThyroSeq v3 genomic classifier reveals the complexity of the genetic signature of indeterminate nodules.
A task‐based approach to parallel parametric linear programming solving, and application to polyhedral computations
Authors: Coti Camille , Monniaux David , Yu Hang 
Published: October 2020

SummaryParametric linear programming is a central operation for polyhedral computations, as well as in certain control applications. Here, we propose a task‐based scheme for parallelizing it, with quasi‐linear speedup over large problems. This type of parallel applications is challenging, because several tasks might be computing the same region. In this article, we are presenting the algorithm itself with a parallel redundancy elimination algorithm, and conducting a thorough performance analysis.
Gesture recognition based on surface electromyography‐featureimage
Authors: Cheng Yangwei , Li Gongfa , Yu Mingchao , Jiang Du , Yun Juntong , Liu Ying , Liu Yibo , Chen Disi 
Published: October 2020

SummaryFor the problem of surface electromyography (sEMG) gesture recognition, considering the fact that the traditional machine learning model is susceptible to the sEMG feature extraction method, it is difficult to distinguish the subtle differences between similar gestures. The NinaPro DB1 dataset is used as the research object, and the sEMG feature image and the Convolutional Neural Network (CNN) are combined to recognize 52 gesture movements. The CNN model effectively solves the limitations of traditional machine learning in sEMG gesture recognition, and combines 1‐dim convolution kernel to extract deep abstract features to improve the recognition effect. Finally, the simulation experiment shows that compared with the accuracy of the raw‐sEMG images based on the CNN and the sEMG‐feature‐images based on the CNN and sEMG based on the traditional machine learning, the multi‐sEMG‐features image based on the CNN is the highest, which coming up to 82.54%.