bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nanocrystals Assembled by the Chemical Reaction of the Dispersion Solvent
Authors: Nakanishi Hideyuki , Kawabata Yuto , Tsujiai Shogo , Tanaka Hayato , Teraji Satoshi , Holló Gábor , Lagzi István , Norisuye Tomohisa , Tran‐Cong‐Miyata Qui 
Published: April 2020

AbstractThe development of methods to pattern nanocrystals with different sizes and shapes remains a challenge. In this study, we demonstrate a unique class of bottom‐up approaches to assemble nanocrystals into patterns. Our approach for patterning nanocrystals focuses on the utilization and control of the chemical reaction of solvents surrounding nanocrystals. The photopolymerization of solvent molecules through a photomask creates time‐dependent concentration gradients of the solvents. Dispersed nanocrystals such as silver nanowires (AgNWs) migrate and are gradually organized and integrated into the polymerizing films based on the concentration gradients. The AgNW‐embedded film properties are determined by the organized AgNW structures and include light transmission and electrical conductivity. Overall, the demonstrated method is very simple, widely applicable to various nanocrystals and solvents, and can thus contribute to the development of a new class of nanocrystal patterning methods.
Efficient Chemical Protein Synthesis using Fmoc‐Masked N‐Terminal Cysteine in Peptide Thioester Segments
Authors: Kar Abhisek , Mannuthodikayil Jamsad , Singh Sameer , Biswas Anamika , Dubey Puneet , Das Amit , Mandal Kalyaneswar 
Published: April 2020

AbstractWe report an operationally simple method to facilitate chemical protein synthesis by fully convergent and one‐pot native chemical ligations utilizing the fluorenylmethyloxycarbonyl (Fmoc) moiety as an N‐masking group of the N‐terminal cysteine of the middle peptide thioester segment(s). The Fmoc group is stable to the harsh oxidative conditions frequently used to generate peptide thioesters from peptide hydrazide or o‐aminoanilide. The ready availability of Fmoc‐Cys(Trt)‐OH, which is routinely used in Fmoc solid‐phase peptide synthesis, where the Fmoc group is pre‐installed on cysteine residue, minimizes additional steps required for the temporary protection of the N‐terminal cysteinyl peptides. The Fmoc group is readily removed after ligation by short exposure (<7 min) to 20 % piperidine at pH 11 in aqueous conditions at room temperature. Subsequent native chemical ligation reactions can be performed in presence of piperidine in the same solution at pH 7.
A Flexible Organic Single Crystal with Plastic‐Twisting and Elastic‐Bending Capabilities and Polarization‐Rotation Function
Authors: Liu Huapeng , Lu Zhuoqun , Tang Baolei , Qu Cheng , Zhang Zuolun , Zhang Hongyu 
Published: April 2020

AbstractFlexible organic single crystals capable of plastic or elastic deformations have a variety of potential applications. Although the integration of plasticity and elasticity in a crystal is theoretically possible and it may cause rich and complex deformations which are highly demanded for potential applications, the integration is hard to realize in practice. Here, we show that through utilizing different modes of external forces for influencing molecular packing in different crystallographic directions, plastic helical twisting and elastic bending can both be achieved for a crystal, and they can even be realized simultaneously. Detailed crystallographic analyses and contrast experiments disclose the mechanisms behind these two kinds of distinct deformations and their mutual compatibility. Based on the plastically twistable nature of the crystal, a new application field of flexible organic single crystals, namely polarization rotators, is successfully opened up.
Designed Asymmetric Protein Assembly on a Symmetric Scaffold
Authors: Lemmens Lenne J. M. , Roodhuizen Job A. L. , de Greef Tom F. A. , Markvoort Albert J. , Brunsveld Luc 
Published: April 2020

AbstractCellular signaling is regulated by the assembly of proteins into higher‐order complexes. Bottom‐up creation of synthetic protein assemblies, especially asymmetric complexes, is highly challenging. Presented here is the design and implementation of asymmetric assembly of a ternary protein complex facilitated by Rosetta modeling and thermodynamic analysis. The wild‐type symmetric CT32–CT32 interface of the 14‐3‐3–CT32 complex was targeted, ultimately favoring asymmetric assembly on the 14‐3‐3 scaffold. Biochemical studies, supported by mass‐balance models, allowed characterization of the parameters driving asymmetric assembly. Importantly, our work reveals that both the individual binding affinities and cooperativity between the assembling components are crucial when designing higher‐order protein complexes. Enzyme complementation on the 14‐3‐3 scaffold highlighted that interface engineering of a symmetric ternary complex generates asymmetric protein complexes with new functions.
Unveiling the Local Structure of Palladium Loaded into Imine‐Linked Layered Covalent Organic Frameworks for Cross‐Coupling Catalysis
Authors: Romero‐Muñiz Ignacio , Mavrandonakis Andreas , Albacete Pablo , Vega Alicia , Briois Valérie , Zamora Félix , Platero‐Prats Ana E. 
Published: April 2020

AbstractLayered covalent organic frameworks (2D‐COFs), composed of reversible imine linkages and accessible pores, offer versatility for chemical modifications towards the development of catalytic materials. Nitrogen‐enriched COFs are good candidates for binding Pd species. Understanding the local structure of reacting Pd sites bonded to the COF pores is key to rationalize interactions between active sites and porous surfaces. By combining advanced synchrotron characterization methods with periodic computational DFT modeling, the precise atomic structure of catalytic Pd sites attached to local defects is resolved within an archetypical imine‐linked 2D‐COF. This material was synthesized using an in situ method as a gel, under which imine hydrolysis and metalation reactions are coupled. Local defects formed in situ within imine‐linked 2D‐COF materials are highly reactive towards Pd metalation, resulting in active materials for Suzuki–Miyaura cross‐coupling reactions.
The structures and properties of bio‐based polyamide 56 fibers prepared by high‐speed spinning
Authors: Wang Yu , Kang Hong‐liang , Guo Ya‐fei , Liu Rui‐gang , Hao Xin‐min , Qiao Rong‐rong , Yan Jin‐long 
Published: April 2020

AbstractBio‐based polyamide 56 (PA56) fibers with the circular and trefoil cross‐sections were prepared by high‐speed spinning process. The pre‐oriented yarns (POY) and draw‐textured yarns (DTY) of PA56 were studied. The results showed that γ phase crystal dominated in POY with relative high degrees in the crystallinity and crystal orientation. In DTY, the drawing effect made the crystal transform from γ to α phase with the properties of the enhanced thickness of the crystal plate and the more order arranged molecules, that was the long period in these fibers was obviously increased to 7–8 nm. γ to α phase transition was much easy for PA56 fibers with circular cross‐section during drawing. PA56 fibers had excellent moisture absorption and release performances. They were easy to be dyed and had a good color fastness.
Azulene in Polymers and Their Properties
Authors: Zeng Hui Ning , Png Zhuang Mao , Xu Jianwei 
Published: April 2020

AbstractAzulene, a unique isomer of naphthalene, has received much interest from researchers in different fields due to its unusual chemical structure with a negatively charged 5‐membered ring fused with a positively charged 7‐membered ring. In particular, incorporation of azulene into polymers has led to many interesting properties. This minireview covers functionalization methods of azulene at its various positions of 5‐ and 7‐membered rings to form azulene derivatives including azulene monomers, and gives an overview of a wide range of azulene‐containing polymers including poly(1,3‐azulene), azulene‐based copolymers with connectivity at 1,3‐positions of the 5‐membered ring, or 4,7‐positions of the 7‐membered ring, as well as copolymers with azulene units as side chains. Their chemical and physical properties together with applications of azulene‐containing polymers have also been summarized.
The mean‐reverting 4/2 stochastic volatility model: Properties and financial applications
Authors: Escobar‐Anel Marcos , Gong Zhenxian 
Published: April 2020

AbstractThis article defines and studies a stochastic process that combines two important stylized facts of financial data: reversion to the mean, and a flexible generalized stochastic volatility process: the 4/2 process. This work is motivated by the modeling of at least two financial asset classes: commodities and volatility indexes. We provide analytical expressions for the conditional characteristic functions and closed‐form approximations to relevant cases, in particular a mean‐reverting Heston stochastic volatility model. Our results describe feasible changes of measure with the final aim of pricing financial derivatives. The empirical analysis and the estimation methodology confirm the need of such a model in several examples from the targeted asset classes. Applications to option pricing corroborate the substantial impact on the implied volatility surfaces of the new parameters.
Construction of the tetration distribution based on the continuous iteration of the exponential‐minus‐one function
Authors: Dijoux Yann 
Published: April 2020

AbstractA new class of lifetime distributions, called tetration distribution, is presented based on the continuous iteration of the exponential‐minus‐one function. In particular, this distribution encompasses and extends the Weibull, Pareto, and Gompertz distributions. In addition, a characterization of the tail of the distribution is proposed through two indices, one of them encompassing the Pareto and Weibull tail indices. Finally, an inference procedure based on rank regression is implemented for the tetration distribution and applied to multiple datasets from the reliability field.
Synthesis and Characteristics of Pyrrolidinium‐Based Organic Ionic Plastic Crystals with Various Sulfonylamide Anions
Authors: Yoshizawa‐Fujita Masahiro , Yamada Hiromasa , Yamaguchi Shun , Zhu Haijin , Forsyth Maria , Takeoka Yuko , Rikukawa Masahiro 
Published: April 2020

AbstractOrganic ionic plastic crystals (OIPCs) have been studied as solid‐state electrolytes owing to their desirable properties such as plasticity, non‐flammability, and high ionic conductivity. However, the relationship between the ion structures and the properties of OIPCs are poorly understood. To supplement our previous work on the effects of the side chain structure of pyrrolidinium salts on their properties, this study examined the effects of the anion structure. For this purpose, five N,N‐diethylpyrrolidinium ([C2epyr]) salts with various sulfonylamide anions were synthesized. The [C2epyr] salts with bis(fluorosulfonyl)amide ([FSA]) and bis(pentafluoroethanesulfonyl)amide ([BETA]) exhibited higher ionic conductivity values at room temperature than the other [C2epyr] salts. The 1H and 19F solid‐state NMR results indicated that the component ions in [C2epyr][FSA] and [C2epyr][BETA] exhibited high rotational mobility, even in the solid state. Thus, rotational mobility is likely important for achieving high ionic conductivity.
Endogenous carbohydrate esterases of Clostridium thermocellum are identified and disrupted for enhanced isobutyl acetate production from cellulose
Authors: Seo Hyeongmin , Nicely Preston N. , Trinh Cong T. 
Published: April 2020

AbstractMedium‐chain esters are versatile chemicals with broad applications as flavors, fragrances, solvents, and potential drop‐in biofuels. Currently, these esters are largely produced by the conventional chemical process that uses harsh operating conditions and requires high energy input. Alternatively, the microbial conversion route has recently emerged as a promising platform for sustainable and renewable ester production. The ester biosynthesis pathways can utilize either lipases or alcohol acyltransferase (AAT), but the AAT‐dependent pathway is more thermodynamically favorable in an aqueous fermentation environment. Even though a cellulolytic thermophile Clostridium thermocellum harboring an AAT‐dependent pathway has recently been engineered for direct conversion of lignocellulosic biomass into esters, the production is not efficient. One potential bottleneck is the ester degradation caused by the endogenous carbohydrate esterases (CEs) whose functional roles are poorly understood. The challenge is to identify and disrupt CEs that can alleviate ester degradation while not negatively affecting the efficient and robust capability of C. thermocellum for lignocellulosic biomass deconstruction. In this study, by using bioinformatics, comparative genomics, and enzymatic analysis to screen a library of CEs, we identified and disrupted the two most critical CEs, Clo1313_0613 and Clo1313_0693, that significantly contribute to isobutyl acetate degradation in C. thermocellum. We demonstrated that an engineered esterase‐deficient C. thermocellum strain not only reduced ester hydrolysis but also improved isobutyl acetate production while maintaining effective cellulose assimilation.
Liver transplantation for unresectable colorectal liver metastases in patients and donors with extended criteria (SECA-II arm D study)
Authors: Smedman T M , Line P-D , Hagness M , Syversveen T , Grut H , Dueland S 
Published: April 2020

Abstract

Background
Patients with metastatic colorectal cancer receiving palliative chemotherapy have a 5-year survival rate of approximately 10 per cent. Liver transplantation using strict selection criteria in patients with colorectal cancer and unresectable liver-only disease will result in a 5-year survival rate of 56–83 per cent. The aim of this study was to evaluate survival of patients with colorectal liver metastases (CRLM) after liver transplantation using extended criteria for both patients and donors.

Methods
This was a prospective single-arm study. Patients with synchronous unresectable CRLM who were not suitable for arms A, B or C of the SEcondary CAncer (SECA) II study who had undergone radical resection of the primary tumour and received chemotherapy were included; they underwent liver transplantation with extended criteria donor grafts. Patients who had resectable pulmonary metastases were eligible for inclusion. The main exclusion criteria were BMI above 30 kg/m2 and liver metastases larger than 10 cm. Survival was estimated using Kaplan–Meier analysis.

Results
Ten patients (median age 54 years; 3 women) were included. They had an extensive liver tumour load with a median of 20 (range 1–45) lesions; the median size of the largest lesion was 59 (range 15–94) mm. Eight patients had (y)pN2 disease, six had poorly differentiated or signet ring cell-differentiated primary tumours, and five had primary tumour in the ascending colon. The median Fong clinical risk score was 3 (range 2–5) and the median Oslo score was 1 (range 1–4). The median plasma carcinoembryonic antigen level was 4·3 (range 2–4346) μg/l. Median disease-free and overall survival was 4 and 18 months respectively.

Conclusion
Patients with unresectable liver-only CRLM undergoing liver transplantation with extended patient and donor criteria have relatively short overall survival.
The trajectory of gait development in mice
Authors: Akula Shyam K. , McCullough Katherine B. , Weichselbaum Claire , Dougherty Joseph D. , Maloney Susan E. 
Published: April 2020

AbstractObjectiveGait irregularities are prevalent in neurodevelopmental disorders (NDDs). However, there is a paucity of information on gait phenotypes in NDD experimental models. This is in part due to the lack of understanding of the normal developmental trajectory of gait maturation in the mouse.Materials and methodsUsing the DigiGait system, we have developed a quantitative, standardized, and reproducible assay of developmental gait metrics in commonly used mouse strains that can be added to the battery of mouse model phenotyping. With this assay, we characterized the trajectory of gait in the developing C57BL/6J and FVB/AntJ mouse lines.ResultsIn both lines, a mature stride consisted of 40% swing and 60% stance in the forelimbs, which mirrors the mature human stride. In C57BL/6J mice, developmental trajectories were observed for stance width, paw overlap distance, braking and propulsion time, rate of stance loading, peak paw area, and metrics of intraindividual variability. In FVB/AntJ mice, developmental trajectories were observed for percent shared stance, paw overlap distance, rate of stance loading, and peak paw area, although in different directions than C57 mice. By accounting for the impact of body length on stride measurements, we demonstrate the importance of considering body length when interpreting gait metrics.ConclusionOverall, our results show that aspects of mouse gait development parallel a timeline of normal human gait development, such as the percent of stride that is stance phase and swing phase. This study may be used as a standard reference for developmental gait phenotyping of murine models, such as models of neurodevelopmental disease.
Role of Two Exceptional trans Adenylation Domains and MbtH‐like Proteins in the Biosynthesis of the Nonribosomal Peptide WS9324A from Streptomyces calvus ATCC 13382
Authors: Bernhardt Mirjam , Berman Stefanie , Zechel David , Bechthold Andreas 
Published: April 2020

AbstractNonribosomal peptide synthetases (NRPS) are organized in a modular arrangement. Usually, the modular order corresponds to the assembly of the amino acids in the respective peptide, following the collinearity rule. The WS9326A biosynthetic gene cluster from Streptomyces calvus shows deviations from this rule. Most interesting is the presence of two trans adenylation domains that are located downstream of the modular NRPS arrangement. Adenylation domains are responsible for the activation of their respective amino acids. In this study, we confirmed the involvement of the trans adenylation domains in WS9326A biosynthesis by performing gene knockout experiments and by observing the selective adenylation of their predicted amino acid substrates in vitro. We conclude that the trans adenylation domains are essential for WS9326A biosynthesis. Moreover, both adenylation domains are observed to have MbtH‐like protein dependency. Overall, we conclude that the trans adenylation domains are essential for WS9326A biosynthesis.
Outcomes of Impella‐supported high‐risk nonemergent percutaneous coronary intervention in a large single‐center registry
Authors: Azzalini Lorenzo , Johal Gurpreet S. , Baber Usman , Bander Jeffrey , Moreno Pedro R. , Bazi Lucas , Kapur Vishal , Barman Nitin , Kini Annapoorna S. , Sharma Samin K. 
Published: April 2020

AbstractObjectivesWe aimed to evaluate the early and one‐year outcomes of Impella‐supported high‐risk nonemergent percutaneous coronary intervention (PCI).BackgroundThe evidence for the use of mechanical circulatory support (MCS) devices in high‐risk nonemergent PCI is limited and nonconclusive.MethodsWe performed a single‐center retrospective study including all patients who underwent high‐risk nonemergent PCI supported by Impella 2.5/CP at our institution between January 2009 and June 2018. This patient population was propensity score matched with subjects undergoing PCI with no MCS. The primary endpoint was major adverse cardiac events (MACE: all‐cause death, myocardial infarction [MI], and target lesion revascularization) at one‐year follow‐up.ResultsTwo‐hundred fifty patients undergoing Impella‐supported nonemergent PCI were matched to 250 controls. The two groups were well balanced in terms of clinical and angiographic characteristics. Left main PCI was performed more frequently among Impella‐supported patients (26% vs. 11%, p < .001), who also had numerically higher prevalence of rotational atherectomy use (44% vs. 37%, p = .10) and a higher number of vessels treated (1.8 ± 0.8 vs. 1.3 ± 0.6, p < .001), compared with controls. Impella‐supported patients suffered a higher incidence of periprocedural MI (14.0% vs. 6.4%, p = .005), major bleeding (6.8% vs. 2.8%, p = .04), and need for blood transfusions (11.2% vs. 4.8%, p = .008). However, at one‐year follow‐up there were no differences in the rates of MACE (31.2% vs. 27.4%, p = .78) or any of its individual components between Impella‐supported patients and controls.ConclusionsAlthough Impella‐supported patients suffer a higher incidence of periprocedural adverse events (partially linked to more aggressive PCI), the incidence of one‐year MACE was similar between the Impella and control group.
Carbon Pathways, Sodium‐Sulphur Promotion and Identification of Iron Carbides in Iron‐based Fischer‐Tropsch Synthesis
Authors: Paalanen Pasi P. , Weckhuysen Bert M. 
Published: April 2020

AbstractFisher‐Tropsch Synthesis (FTS) is industrially used for converting a carbon‐containing feedstock, such as coal, natural gas, biomass, and municipal waste, via the production of synthesis gas (a mixture of CO+H2) into hydrocarbons. This review article focuses on Fe‐based FTS catalysis, thereby focusing on the process conditions available for steering the various carbon pathways from input CO and their associated reactions. We will also discuss the effects of alkali‐sulphur chemical promotion and the identification of the FTS reaction active Fe carbides, which are assigned with precise crystal structures and nomenclature. Each observed Fe carbide crystal structure is further assigned with corresponding Mössbauer Absorption Spectroscopy (MAS) hyperfine fields. The expected formation temperatures and experimental conditions for the identified Fe carbides encountered in FTS research, namely ϵ‐Fe3C, η‐Fe2C, χ‐Fe5C2, θ‐Fe3C and θ‐Fe7C3, are reviewed.
Synergistic Inhibitory Effect of Potassium Sodium Tartrate Tetrahydrate and Sodium Stannate Trihydrate on Self‐Corrosion of Aluminum in Alkaline Aluminum‐Air Batteries
Authors: Taeri Omid , Hassanzadeh Ali , Ravari Fateme 
Published: April 2020

AbstractTo promote the efficiency of aluminum‐air batteries, the present paper proposes using inhibitor for decreasing anodic corrosion; therefor, the self‐corrosion of pure aluminum sheet (PAS) in KOH (1 M) solution at different concentrations of two inhibitors; potassium sodium tartrate tetrahydrate (STT) and sodium stannate trihydrate (SST) has been investigated both individually and collectively. The characteristics of PAS were studied through electrochemical methods including Tafel polarization curves, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and energy‐dispersive X‐ray spectroscopy (EDS). The results indicate that inhibition efficiencies for both inhibitors (STT and SST) increased with a rise in concentration of the inhibitors reaching a maximum in one certain concentration called optimum concentration. The constant current discharge plots for the assembled prototype aluminum‐air battery were also obtained, further confirming the aforementioned results. Finally, the calculated anode efficiency results indicate that the addition of mix inhibitor into electrolyte demonstrates the highest impact compared with the others, which should be attributed to the significantly reduced self‐corrosion reaction.