bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent Advance of Transition‐Metal‐Based Layered Double Hydroxide Nanosheets: Synthesis, Properties, Modification, and Electrocatalytic Applications
Authors: Yi Huan , Liu Shiyu , Lai Cui , Zeng Guangming , Li Minfang , Liu Xigui , Li Bisheng , Huo Xiuqin , Qin Lei , Li Ling , Zhang Mingming , Fu Yukui , An Ziwen , Chen Liang 
Published: February 2021

AbstractNowadays, to alleviate the growing pressure of energy shortages and environmental pollution, electrochemical energy conversion is seen as a fossil‐free, secondary pollution‐free, and highly efficiency pathway. Electrocatalysts, as the “heart” of the electrochemical conversion process, play a key role in accelerating reaction rates and promoting efficiency. Transition‐metal‐based layered double hydroxides (TM LDHs), one of the famous electrocatalysts, show unique 2D supermolecular‐stratified structure, excellent electronic properties, and their raw materials are easily available. In this review, electrocatalysis‐related properties of TM LDHs and the state‐of‐the‐art synthesis methods of TM LDH‐based electrocatalysts are summarized. Modifications for promoting the development of TM LDH‐based electrocatalysts are included, such as carbon materials modification, defect engineering, and noble metal loading. Then, the application of TM LDH nanosheets in the field of electrocatalysis is reviewed in detail. Finally, recent challenges, ongoing improvements, and future expectations for TM LDH nanosheets are presented.
Present Status of Solution‐Processing Routes for Cu(In,Ga)(S,Se)2 Solar Cell Absorbers
Authors: Suresh Sunil , Uhl Alexander R. 
Published: February 2021

AbstractPhotovoltaic technologies offer a sustainable solution to the challenge of meeting increasing energy demands. Chalcopyrite Cu(In,Ga)(S,Se)2, short CIGS—thin‐film solar cells—having intrinsically p‐type absorbers with a tunable direct bandgap—exhibits one of the highest stabilized power conversion efficiencies of 23.35%, utilizing absorbers typically fabricated via vacuum deposition methods. Research is increasingly devoted to absorbers deposited by solution processing techniques, which may inherently improve material usage, increase throughput, and lower financial barriers to commercialization. However, the performance of current devices with solution‐processed absorbers is still falling short of their vacuum‐processed counterparts with record power conversion efficiencies up to 18.7% reported to date. While hydrazine solvent‐based routes offer reduced residual impurities, their toxicity poses hindrances to widespread adoption. Alternatively, less toxic and environmentally friendly routes based on protic and aprotic solvents are being researched and are showing promising device efficiencies well above 14%. This review describes the current status of CIGS solar cell absorber layers fabricated by pure solution‐based deposition methods, provides a comparison of champion solution‐processed devices (with and without hydrazine), and offers an outlook for future improvements.
Plant productivity and nutrient uptake as affected by tillage and site‐position in furrow‐irrigated rice
Authors: Della Lunga Diego , Brye Kristofor R. , Henry Christopher G. , Slayden Jordan M. 
Published: February 2021

AbstractFurrow‐irrigated rice (Oryza sativa L.) is a relatively new production system that has been shown to have increased water‐use efficiency and reduced operational costs. However, due to spatial variations in soil moisture, field studies are necessary to evaluate potential resulting variations in rice growth and yield in the furrow‐irrigated production system. This study was conducted to evaluate the effects of tillage practice (conventional tillage, CT; no‐tillage, NT) and site position (up‐, mid‐, and down‐slope) on aboveground biomass, yield, and plant nutrient uptake from rice grown in a silt‐loam soil in a direct‐seeded, furrow‐irrigated production system in eastern Arkansas. Field research was conducted from May to September during the 2018 and 2019 rice growing seasons. Total aboveground dry matter, vegetative dry matter, and yield were unaffected (P > .05) by tillage treatment or site position in either growing season. Vegetative tissue nutrient concentrations and uptake were generally at least 10% greater (P < .05) under CT than NT but did not substantially differ by site position during the drier growing season (2018). During the wetter growing season (2019), vegetative tissue nutrient concentrations and uptake were generally at least 20% greater (P < .05) at the up‐ than at the mid‐ or down‐slope positions. Results suggest that different approaches, in terms of soil and nutrient management per site position, in combination with tillage practices, may need to be considered for implementation to maximize nutrient uptake and reduce losses, thus improving the agronomic suitability of the furrow‐irrigated rice production system.
Enzyme‐Primed Native Chemical Ligation Produces Autoinducing Cyclopeptides in Clostridia
Authors: Molloy Evelyn M. , Dell Maria , Hänsch Veit G. , Dunbar Kyle L. , Feldmann Romy , Oberheide Ansgar , Seyfarth Lydia , Kumpfmüller Jana , Horch Therese , Arndt Hans‐Dieter , Hertweck Christian 
Published: February 2021

AbstractClostridia coordinate many important processes such as toxin production, infection, and survival by density‐dependent communication (quorum sensing) using autoinducing peptides (AIPs). Although clostridial AIPs have been proposed to be (thio)lactone‐containing peptides, their true structures remain elusive. Here, we report the genome‐guided discovery of an AIP that controls endospore formation in Ruminiclostridium cellulolyticum. Through a combination of chemical synthesis and chemical complementation assays with a mutant strain, we reveal that the genuine chemical mediator is a homodetic cyclopeptide (cAIP). Kinetic analyses indicate that the mature cAIP is produced via a cryptic thiolactone intermediate that undergoes a rapid S→N acyl shift, in a manner similar to intramolecular native chemical ligation (NCL). Finally, by implementing a chemical probe in a targeted screen, we show that this novel enzyme‐primed, intramolecular NCL is a widespread feature of clostridial AIP biosynthesis.
Self‐Assembly of Size‐Controlled m‐Pyridine–Urea Oligomers and Their Biomimetic Chloride Ion Channels
Authors: Chen Hualong , Liu Yajing , Cheng Xuebo , Fang Senbiao , Sun Yuli , Yang Zequn , Zheng Wei , Ji Xunming , Wu Zehui 
Published: February 2021

AbstractThe m‐pyridine urea (mPU) oligomer was constructed by using the intramolecular hydrogen bond formed by the pyridine nitrogen atom and the NH of urea and the intermolecular hydrogen bond of the terminal carbonyl group and the NH of urea. Due to the synergistic effect of hydrogen bonds, mPU oligomer folds and exhibits strong self‐assembly behaviour. Affected by folding, mPU oligomer generates a twisted plane, and one of its important features is that the carbonyl group of the urea group orientates outwards from the twisted plane, while the NHs tend to direct inward. This feature is beneficial to NH attraction for electron‐rich species. Among them, the trimer self‐assembles into helical nanotubes, and can efficiently transport chloride ions. This study provides a novel and efficient strategy for constructing self‐assembled biomimetic materials for electron‐rich species transmission.
Approach in Macadamia integrifolia residue based low‐density polyethylene composites on mechanical and thermal performance
Authors: dos Santos Andrade Laert , Silva Nycolle Gonçalves Souza , de Ornellas Cortat Lucas Inácio Cruz , Mulinari Daniella Regina 
Published: February 2021

AbstractMacadamia nutshell residues are generated in large quantities, around 70%–77% for each ton produced, and it is a waste material with high techno‐economic potential. This work purpose a sustainable alternative to valorize macadamia nutshell residues (MN) as reinforcing in low‐density polyethylene (LDPE) composites through melt mixing, using different fiber contents (0, 5, 10, and 20 wt%), and investigate the influence of fibers (residues) in composites by mechanical tests and thermal analysis. The fibers addition has significantly increased the composites' stiffness compared with neat LDPE, causing a reduction of toughness and resilience, leading to lower impact energy absorption. The LPDE/MN20% composite obtained the best tensile and flexural mechanical performance, resulting in a maximum modulus, which implies an increase of 36.9% and 77.6% compared with the neat LDPE. The addition of macadamia fibers on the composites acted as nucleation points of spherulites, which promoted an increase in the crystallization degree. Consequently, better performance of mechanical properties was observed in the green composites. Thus, the macadamia nutshell residues present a promising future as filler in LDPE for enhancing composites' thermal and mechanical properties.
Effects of polyphosphoric acid (PPA), styrene‐butadiene‐styrene (SBS), or rock asphalt on the performance of desulfurized rubber modified asphalt
Authors: Liu Hengbin , Zhang Zhengqi , Li Zhuolin , Li Naiqiang 
Published: February 2021

AbstractTo improve the performance of desulfurized rubber modified asphalt (DRMA), especially its high‐temperature performance, three modifiers (including polyphosphoric acid [PPA], styrene‐butadiene‐styrene [SBS], and rock asphalt) were selected to modify DRMA respectively. The conventional performance, rheological properties, chemical composition, and thermal decomposition were characterized to analyze the performance and modification mechanism of DRMA and its composites. Test results show that, the addition of PPA, SBS, and rock asphalt can all improve the high temperature of DRMA, among which the desulfurized rubber/rock asphalt compound modified asphalt (DRMA‐ROCK) has the best high‐temperature performance; however, its construction workability, storage stability, and low‐temperature performance are poor. In contrast, desulfurized rubber/PPA compound modified asphalt (DRMA‐PPA) not only has better high‐temperature performance, but also has excellent low‐temperature performance, storage stability, and fatigue performance. Fourier infrared spectroscopy (FTIR) test confirms that the modification process of DRMA by these modifiers is chemical modification, and the characteristic peak indexes obtained from FTIR also prove that DRMA‐ROCK has better high‐temperature performance but poor construction workability from the microscopic point of view. Furthermore, thermogravimetric analysis‐differential scanning calorimetry test shows that the addition of rock asphalt improves the thermal stability of DRMA, while PPA and SBS decrease its thermal stability. From the above results, it can be concluded that DRMA‐PPA has excellent comprehensive properties.
Flame‐retardant behavior and mechanism of theSBR/MMTcomposites modified by melamine matrix modifier
Authors: Cheng Guojun , Xuan Ziyue , Tang Zhongfeng , Tian Shen , Sha Feixiang , Ding Guoxin , Wan Xianglong 
Published: February 2021

AbstractMelamine quaternary ammonium salt (MQAS), a novel flame‐retardant intercalation modifier, was used to prepare the flame‐retardant organic montmorillonite (FOSM), and which was added to SBR by a two‐roll mixing and molding process to prepared the SBR/FOSM composites. The synergistic flame‐retardant effects of sodium‐based montmorillonite (MMT) and MQAS were investigated by the various methods. The LOI value of SBR was only 19.1%, and FOSM‐4 increased the LOI value of SBR to 24.3%. The cone calorimetry test showed that compared with SBR, the total heat release and the peak heat release rate of SBR/FOSM were reduced by 81.39% and 86.08%, respectively. The analysis of MMT after modification showed that the grafting rate of MQAS was about 10% and the interlayer spacing of MMT was enlarged by about 20%. The synergy of MQAS and MMT not only effectively solves the violent droplet of pure SBR combustion, but also avoids the curling problem of only adding MMT. The char morphology and TG‐FTIR showed that FOSM had dual flame‐retardancy in the condensed phase and the gas phase. The synergistic flame‐retardant effect of phosphorus‐free flame‐retardant modifier and MMT will open up new possibilities for flame‐retardant elastomer composites.
Structural and functional diversity of asparaginases: Overview and recommendations for a revised nomenclature
Authors: da Silva Leonardo Schultz , Doonan Liam B. , Pessoa Adalberto , de Oliveira Marcos Antonio , Long Paul F. 
Published: February 2021

AbstractAsparaginases (ASNases) are a large and structurally diverse group of enzymes ubiquitous amongst archaea, bacteria and eukaryotes, that catalyze hydrolysis of asparagine to aspartate and ammonia. Bacterial ASNases are important biopharmaceuticals for the treatment of acute lymphoblastic leukemia, although some patients experience adverse allergic side effects during treatment with these protein therapeutics. ASNases are currently divided into three families: plant‐type ASNases, Rhizobium etli‐type ASNases and bacterial‐type ASNases. This system is outdated as both bacterial‐type and plant‐type families also include archaeal, bacterial and eukaryotic enzymes, each with their own distinct characteristics. Herein, phylogenetic studies allied to tertiary structural analyses are described with the aim of proposing a revised and more robust classification system that considers the biochemical diversity of ASNases. Accordingly, based on distinct peptide domains, phylogenetic data, structural analysis and functional characteristics, we recommend that ASNases now be divided into three new distinct classes containing subgroups according to structural and functional aspects. Using this new classification scheme, 25 ASNases were identified as candidates for future new lead discovery.
Biegefestigkeit von Segmentlamellenholz
Authors: Windeck Lukas , Hirmke Markus 
Published: February 2021

AbstractSegmentlamellenholz ist einer neuer, aus wechselseitig verklebten Kreissektoren bestehender Holzwerkstoff, der als Alternative zu BSH und KVH angesehen wird. Durch den vom Industriestandard abweichenden Einschnitt in trapezförmige Querschnitte mittels radialer Schnitte kann der Rohstoff Holz deutlich effizienter genutzt werden. Vierpunkt‐Biegeversuche, die im Rahmen der Erstellung einer ETA durchgeführt wurden, zeigten, dass Segmentschichtholzträger Biegefestigkeiten erreichen, die mit denjenigen von BSH GL24 vergleichbar sind. Die Ergebnisse der Versuche werden hier vorgestellt. Weiterhin zeigen die Simulationsergebnisse eines neu entwickelten FE‐Modells basierend auf dem Karlsruher Rechenmodell auf, wie sich die Biegefestigkeiten von Segmentschichtholz bei großen Trägerhöhen entwickeln. Die weitere Forschungsarbeit soll aufzeigen, wie der Herstellungsprozess hinsichtlich der resultierenden Biegefestigkeit optimiert werden kann.
Educational interactive LabVIEW simulations of field hydraulic conductivity tests below water table
Authors: Allawi Faridoun A. M. 
Published: February 2021

AbstractVisual artifacts used in graphical designs of the mechanisms of groundwater flow problems are very influential in learning and teaching. The merits of the classical methods of problem‐solving using only mathematics become much less superior to those linked with interactive graphics. In this study, an interactive educational LabVIEW program is designed to graphically simulate the constructional and mathematical procedures of the two widely used field methods in groundwater engineering, the Ernst auger‐hole method, and the Bouwer–Rice slug test method, for field measurements of the hydraulic conductivity of soils below the water table. The simulations included the basic constructional steps in carrying out the auger hole and the slug test field methods. Virtual geometric wells, boreholes, and pipes are graphically and interactively designed to conduct the required field tests. The simulations of the program enabled the students to get acquainted with what should be done in the field to measure soil hydraulic conductivity and enhanced understanding of how to perform a field test. Students were able to try different field hydrological parameters, and by successively changing any hydrological field parameter, they were able to visualize graphically and interactively its influence inside the classroom. This particular step improved the student's practical standards. Conditions of validity of each field test are completely fulfilled by the program. Results of the interactive program are found to be visually interesting and extremely accurate, which made this educational program quite interesting in teaching and learning.
Comparative prognostic value of different preoperative complete blood count cell ratios in patients with oral cavity cancer treated with surgery and postoperative radiotherapy
Authors: Wu Yao‐Yu , Chang Kai‐Ping , Ho Tsung‐Ying , Chou Wen‐Chi , Hung Sheng‐Ping , Fan Kang‐Hsing , Chiang Yin‐Yin , Chou Yung‐Chih , Tsang Ngan‐Ming 
Published: February 2021

AbstractBackgroundWe sought to compare the prognostic significance of different preoperative complete blood count cell ratios in patients with oral cavity squamous cell carcinoma (OSCC) treated with surgery and postoperative radiotherapy (PORT).MethodsWe retrospectively reviewed the clinical records of 890 patients with OSCC who were treated with surgery and PORT. The following preoperative complete blood count cell ratios were collected: neutrophil‐to‐lymphocyte ratio (NLR), platelet‐to‐lymphocyte ratio (PLR), and lymphocyte‐to‐monocyte ratio (LMR). Overall survival (OS), local control, regional control, and distant control (DC) served as the main outcomes of interest.ResultsThe results of multivariate analysis in the entire study cohort revealed that a low NLR was the only independently favorable marker of both OS (adjusted hazard ratio [HR]: 0.794, 95% confidence interval (CI): 0.656–0.961, bootstrap p = 0.028) and DC (adjusted HR: 0.659, 95% CI: 0.478–0.909, bootstrap p = 0.015). Both LMR and PLR were not retained in the model as independent predictors. Subgroup analyses in high‐risk patients (i.e., those bearing T4 disease, N3 disease, or poor differentiation) revealed that a high NLR was a significant adverse risk factor for both OS and DC (all p < 0.03)—with a borderline significance being evident for DC in patients with T4 disease (p = 0.058).ConclusionsA high pretreatment NLR was an independent unfavorable risk factor for both OS and DC in patients with OSCC who underwent surgery and PORT. No other preoperative complete blood count parameters and cell ratios were found to have prognostic significance.
Microfluidic Desalination: A New Era Towards Sustainable Water Resources
Authors: Abdulbari Hayder A , Basheer Esmail 
Published: February 2021

AbstractWater desalination is considered one of the most critical separation technologies that suffer from several drawbacks, such as the power consumption that controls the separation efficiency. Microfluidics technology provided a unique opportunity to introduce cutting edge products and to re‐visit existing technologies like desalination for evaluation, optimization, and new product introduction purposes. It is believed that the micro‐mixing and micro‐separation features in a microfluidic flow system will contribute significantly to enhance the desalination performance of known desalination techniques. Micro‐mixing and micro‐separation in a microfluidic device can eliminate the poor mixing and separation efficiency observed with the bench‐scaled systems due to the high‐precision droplet generation and microfluidic separation features. This review discusses the current state of microfluidic desalination, its operating theory, and its limitations. Additionally, the current technology is reviewed to shed some light on the feasibility of scaling up water production rates. The gap between the application of microfluidic desalination and industrial scale‐up is also described briefly.
Biochemical Investigation of the Interaction of pICln, RioK1 and COPR5 with the PRMT5–MEP50 Complex
Authors: Krzyzanowski Adrian , Gasper Raphael , Adihou Hélène , Hart Peter 't , Waldmann Herbert 
Published: February 2021

AbstractThe PRMT5–MEP50 methyltransferase complex plays a key role in various cancers and is regulated by different protein–protein interactions. Several proteins have been reported to act as adaptor proteins that recruit substrate proteins to the active site of PRMT5 for the methylation of arginine residues. To define the interaction between these adaptor proteins and PRMT5, we employed peptide truncation and mutation studies and prepared truncated protein constructs. We report the characterisation of the interface between the TIM barrel of PRMT5 and the adaptor proteins pICln, RioK1 and COPR5, and identify the consensus amino acid sequence GQF[D/E]DA[E/D] involved in binding. Protein crystallography revealed that the RioK1 derived peptide interacts with a novel PPI site.
Leg ulcer with long‐term hydroxyurea use
Authors: Ammad Ud Din Mohammad , Hussain Syed Ather , Jamshed Saad 
Published: February 2021

AbstractLong‐term use of hydroxyurea can cause leg ulcers which usually do not heal unless the drug is discontinued. Patients should be counseled regarding alternative lines of treatment like anagrelide and pegylated‐interferon.
C−H Bond Arylation of Pyrazoles at the β‐Position: General Conditions and Computational Elucidation for a High Regioselectivity
Authors: Shi Xinzhe , Sosa Carrizo E. Daiann , Cordier Marie , Roger Julien , Pirio Nadine , Hierso Jean‐Cyrille , Fleurat‐Lessard Paul , Soulé Jean‐François , Doucet Henri 
Published: February 2021

AbstractDirect arylation of most five‐membered ring heterocycles are generally easily accessible and strongly favored at the α‐position using classical palladium‐catalysis. Conversely, regioselective functionalization of such heterocycles at the concurrent β‐position remains currently very challenging. Herein, we report general conditions for regioselective direct arylation at the β‐position of pyrazoles, while C−H α‐position is free. By using aryl bromides as the aryl source and a judicious choice of solvent, the arylation reaction of variously N‐substituted pyrazoles simply proceeds via β‐C−H bond functionalization. The β‐regioselectivity is promoted by a ligand‐free palladium catalyst and a simple base without oxidant or further additive, and tolerates a variety of substituents on the bromoarene. DFT calculations revealed that a protic solvent such as 2‐ethoxyethan‐1‐ol significantly enhances the acidity of the proton at β‐position of the pyrazoles and thus favors this direct β‐C−H bond arylation. This selective pyrazoles β‐C−H bond arylation was successfully applied for the straightforward building of π‐extended poly(hetero)aromatic structures via further Pd‐catalyzed combined α‐C−H intermolecular and intramolecular C−H bond arylation in an overall highly atom‐economical process.