bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reductively Caged, Photoactivatable DNA‐PAINT for High‐Throughput Super‐resolution Microscopy
Authors: Jang Soohyun , Kim Mingi , Shim Sang‐Hee 
Published: April 2020

AbstractIn DNA points accumulation in nanoscale topography (DNA‐PAINT), capable of single‐molecule localization microscopy with sub‐10‐nm resolution, the high background stemming from the unbound fluorescent probes in solution limits the imaging speed and throughput. Herein, we reductively cage the fluorescent DNA probes conjugated with a cyanine dye to hydrocyanine, acting as a photoactivatable dark state. The additional dark state from caging lowered the fluorescent background while enabling optically selective activation by total internal reflection (TIR) illumination at 405 nm. These benefits from “reductive caging” helped to increase the localization density or the imaging speed while preserving the image quality. With the aid of high‐density analysis, we could further increase the imaging speed of conventional DNA‐PAINT by two orders of magnitude, making DNA‐PAINT capable of high‐throughput super‐resolution imaging.
Tailoring the Morphology and Fractal Dimension of 2D Mesh‐like Gold Gels
Authors: Hiekel Karl , Jungblut Swetlana , Georgi Maximilian , Eychmüller Alexander 
Published: April 2020

AbstractAs there is a great demand of 2D metal networks, especially out of gold for a plethora of applications we show a universal synthetic method via phase boundary gelation which allows the fabrication of networks displaying areas of up to 2 cm2. They are transferred to many different substrates: glass, glassy carbon, silicon, or polymers such as PDMS. In addition to the standardly used web thickness, the networks are parametrized by their fractal dimension. By variation of experimental conditions, we produced web thicknesses between 4.1 nm and 14.7 nm and fractal dimensions in the span of 1.56 to 1.76 which allows to tailor the structures to fit for various applications. Furthermore, the morphology can be tailored by stacking sheets of the networks. For each different metal network, we determined its optical transmission and sheet resistance. The obtained values of up to 97 % transparency and sheet resistances as low as 55.9 Ω/sq highlight the great potential of the obtained materials.
A Vinyl Cyclopropane Ring Expansion and Iridium‐Catalyzed Hydrogen Borrowing Cascade
Authors: Wübbolt Simon , Cheong Choon Boon , Frost James R. , Christensen Kirsten E. , Donohoe Timothy J. 
Published: April 2020

AbstractA vinyl cyclopropane rearrangement embedded in an iridium‐catalyzed hydrogen borrowing reaction enabled the formation of substituted stereo‐defined cyclopentanes from Ph* methyl ketone and cyclopropyl alcohols. Mechanistic studies provide evidence for the ring‐expansion reaction being the result of a cascade based on oxidation of the cyclopropyl alcohols, followed by aldol condensation with the pentamethyl phenyl‐substituted ketone to form an enone containing the vinyl cyclopropane. Subsequent single electron transfer (SET) to this system initiates a rearrangement, and the catalytic cycle is completed by reduction of the new enone. This process allows for the efficient formation of diversely substituted cyclopentanes as well as the construction of complex bicyclic carbon skeletons containing up to four contiguous stereocentres, all with high diastereoselectivity.
Sulfonium Acids Loaded onto an Unusual Thiotemplate Assembly Line Construct the Cyclopropanol Warhead of a Burkholderia Virulence Factor
Authors: Trottmann Felix , Ishida Keishi , Franke Jakob , Stanišić Aleksa , Ishida‐Ito Mie , Kries Hajo , Pohnert Georg , Hertweck Christian 
Published: April 2020

AbstractPathogenic bacteria of the Burkholderia pseudomallei group cause severe infectious diseases such as glanders and melioidosis. Malleicyprols were identified as important bacterial virulence factors, yet the biosynthetic origin of their cyclopropanol warhead has remained enigmatic. By a combination of mutational analysis and metabolomics we found that sulfonium acids, dimethylsulfoniumpropionate (DMSP) and gonyol, known as osmolytes and as crucial components in the global organosulfur cycle, are key intermediates en route to the cyclopropanol unit. Functional genetics and in vitro analyses uncover a specialized pathway to DMSP involving a rare prokaryotic SET‐domain methyltransferase for a cryptic methylation, and show that DMSP is loaded onto the NRPS‐PKS hybrid assembly line by an adenylation domain dedicated to zwitterionic starter units. Then, the megasynthase transforms DMSP into gonyol, as demonstrated by heterologous pathway reconstitution in E. coli.
A Titanium Metal–Organic Framework with Visible‐Light‐Responsive Photocatalytic Activity
Authors: Cadiau Amandine , Kolobov Nikita , Srinivasan Sivaranjani , Goesten Maarten G. , Haspel Henrik , Bavykina Anastasiya V. , Tchalala Mohamed R. , Maity Partha , Goryachev Andrey , Poryvaev Artem S. , Eddaoudi Mohamed , Fedin Matvey V. , Mohammed Omar F. , Gascon Jorge 
Published: April 2020

AbstractThe one‐step synthesis and characterization of a new and robust titanium‐based metal–organic framework, ACM‐1, is reported. In this structure, which is based on infinite Ti−O chains and 4,4′,4′′,4′′′‐(pyrene‐1,3,6,8‐tetrayl) tetrabenzoic acid as a photosensitizer ligand, the combination of highly mobile photogenerated electrons and a strong hole localization at the organic linker results in large charge‐separation lifetimes. The suitable energies for band gap and conduction band minimum (CBM) offer great potential for a wide range of photocatalytic reactions, from hydrogen evolution to the selective oxidation of organic substrates.
In Situ Formation of Liquid Metals via Galvanic Replacement Reaction to Build Dendrite‐Free Alkali‐Metal‐Ion Batteries
Authors: Ding Yu , Guo Xuelin , Qian Yumin , Gao Hongcai , Weber Daniel H. , Zhang Leyuan , Goodenough John B. , Yu Guihua 
Published: April 2020

AbstractGalvanic replacement reactions have been studied as a versatile route to synthesize nanostructured alloys. However, the galvanic replacement chemistry of alkali metals has rarely been explored. A protective interphase layer will be formed outside templates when the redox potential exceeds the potential windows of nonaqueous solutions, and the complex interfacial chemistry remains elusive. Here, we demonstrate the formation of room‐temperature liquid metal alloys of Na and K via galvanic replacement reaction. The fundamentals of the reaction at such low potentials are investigated via a combined experimental and computational method, which uncovers the critical role of solid‐electrolyte interphase in regulating the migration of Na ions and thus the alloying reaction kinetics. With in situ formed NaK liquid alloys as an anode, the dendritic growth of alkali metals can be eliminated thanks to the deformable and self‐healing features of liquid metals. The proof‐of‐concept battery delivers reasonable electrochemical performance, confirming the generality of this in situ approach and design principle for next‐generation dendrite‐free batteries.
Effect of Chain Length for Dicarboxylic Monomeric Units of Polyester Polyols on the Morphology, Thermal and Mechanical Properties of Thermoplastic Urethanes
Authors: Tuan Ismail Tuan N. M. , Ibrahim Nor A. , Palam Kosheela D. P. , Sendijarevic Aisa , Sendijarevic Ibrahim , M. Schiffman Christi , Hoong Seng S. , Noor Mohd A. M. , Yeong Shoot K. , Idris Zainab , Malek Emilia A. , Zainuddin Norhazlin , Sendijarevic Vahid 
Published: April 2020

AbstractPolyester polyols of 2000 g mol−1 M mass were synthesized via polyesterification reaction of butane‐1,4‐diol (1,4‐BDO) with linear dicarboxylic acids (DCAs) of odd and even carbon numbers, ranging from C4 to C10. Melt transition temperatures and crystallization enthalpies of polyester polyols demonstrated differing trends between odd and even chain lengths of their DCA monomeric units, with the latter possessing higher melt transition temperatures and melting enthalpies. The underlying cause of this difference may be attributable to the formation of a crystalline phase between the polyols' alkyl groups, which leads to proper alignment of ester bonds to allow for formation of dipoles that effectively cancel the local polarization. Thermoplastic urethanes (TPUs) were prepared by reacting the polyester polyols with 4,4′‐methylene bis(phenyl isocyanate) (4,4′‐MDI) and 1,4‐BDO chain extender at mole ratio of 1:2:1, respectively. Morphology, thermal and mechanical properties of TPUs were measured. Mechanical properties of TPUs also differ according to even vs. odd chain length of DCA monomeric units: higher hardness, tensile strength, hysteresis and tensile set for the former. The difference in properties is likely related to differences in phase segregation between hard and soft segments as a result of formation of hydrogen bonds as well as dipole–dipole interactions. Therefore, these findings have practical significance in the selection of polyester polyols to design TPUs for their specific applications.
Tensile deformation and morphology changes in segmented elastomer films and fibers including mechanical property modeling
Authors: Sauer Bryan B. , Kampert William G. 
Published: April 2020

AbstractSegmented polyether soft segment (SS) elastomers with different hard segments (HS) in film and fiber form were studied by birefringence, DSC, and tensile tests. To understand the morphological contributions to property differences, high resolution tapping AFM resolved ribbon‐like highly anisotropic hard domain (HD) lamellae in low modulus Pebax (polyamide 12 HS) and polyetherester (PEE), films, while lower HS content high melting poly(urethane urea) (PUU) had much smaller less anisotropic but higher melting HDs, explaining its enhanced thermal and mechanical hysteresis properties. Stress–strain tensile data demonstrate the excellent strength and toughness of PUUs and some spun PEE fibers, and film and fiber birefringence data applied during strain cycling up to very high stresses provided the molecular basis for the varying properties. The parameters from non‐Gaussian fits of tensile data provide insight into network properties for these systems exhibiting very high strengths and a large degree of strain hardening. Modeling of PEE and Pebax films also shows the effects of substantial plastic yielding of the HD networks. Tensile data were obtained as a function of strain rate and temperature to help understand the contributions of network restructuring and other factors. For fibers, strain rate data spanning seven decades show and unusual drop in strengths at very high strain rates. Temperature‐dependent tensile data also show large differences between PUU materials versus lower melting PEEs.
Preparation of Cr(VI)‐imprinted polypropylene nonwoven fibers using plasma polymerization‐assisted grafting
Authors: Luo Zhengwei , Xu Yiyang , Chen Haonan , Jiang Hui , Geng Wenhua , Wei Wuji , Lian Zhouyang 
Published: April 2020

AbstractPolypropylene (PP) fibers were grafted with glycidyl methacrylate (GMA) using plasma polymerization and then aminated, imprinted, and crosslinked to prepare Cr(VI)‐imprinted fibers. The plasma polymerization conditions were optimized by single factor experiment and response surface methodology, and various properties and adsorption mechanism of the fibers were analyzed. The results showed that at pH 3, the imprinted fibers had a maximum Cr(VI) adsorption capacity of 173.36 mg/g, and the adsorption equilibrium could be reached within 40 min. In the presence of competing ions (SO42−, NO3− and PO43−) each at a concentration of 5 times of that of Cr(VI), the Cr(VI) adsorption rate of the fibers could be maintained at around 50%, which indicates that the imprinted fibers have high selectivity towards Cr(VI). The results also showed that the imprinted fibers had good reusability and enrichment ability, thus can be a good candidate for treating actual Cr(VI)‐contaminated water.
Composite of medium‐chain‐length polyhydroxyalkanoates‐co‐methyl acrylate and carbon nanotubes as innovative electrodes modifier in microbial fuel cell
Authors: Sirajudeen Abdul Azeez Olayiwola , Annuar Mohamad Suffian Mohamad , Subramaniam Ramesh 
Published: April 2020

AbstractA microbial fuel cell is a sustainable and environmental‐friendly device that combines electricity generation and wastewater treatment through metabolic activities of microorganisms. However, low power output from inadequate electron transfer to the anode electrode hampers its practical implementation. Nanocomposites of oxidized carbon nanotubes and medium‐chain‐length polyhydroxyalkanoates (mcl‐PHA) grafted with methyl acrylate monomers enhance the electrochemical function of electrodes in microbial fuel cell. Extensive polymerization of methyl acrylate monomers within mcl‐PHA matrix, and homogenous dispersion of carbon nanotubes within the graft matrix are responsible for the enhancement. Modified electrodes exhibit high conductivities, better redox peak and reduction of cell internal resistance up to 76%. A stable voltage output at almost 700 mV running for 225 H generates maximum power and current density of 351 mW/m2 and 765 mA/m2, respectively. Superior biofilm growth on modified surface is responsible for improved electron transfer to the anode hence stable and elevated power output generation.
New approach for stability study and determination of fluvoxamine in raw materials and pharmaceuticals through condensation with 2,2‐dihydroxyindane‐1,3‐dione
Authors: Abu‐hassan Ahmed A. , Omar Mahmoud A. , Derayea Sayed M. 
Published: April 2020

AbstractThe present study describes the validation of a selective spectroscopic method for assay of fluvoxamine maleate (FXM). The validated method relies on condensation of FXM with 2,2‐dihydroxyindane‐1,3‐dione and phenylacetaldehyde using Teorell–Stenhagen buffer (pH 6.6) to give coloured fluorescent product measured at 482 nm using 386 nm as the excitation wavelength. The parameters influencing the reaction were studied precisely and adjusted accurately. The constructed calibration graph appeared rectilinear over the following range (0.8–14 μg ml−1) and the estimated limit of detection was 0.25 μg ml−1. Two pharmaceutical products from the Egyptian market were assayed using the suggested method and the final results agreed with measurements from other reported methods. Moreover, the drug was subjected to diverse stress conditions including acidic, alkaline, thermal, and photolytic degradation to examine the FXM stability. Directives from the International Conference on Harmonisation guidelines were applied to establish the validity of the work.
Benchmarking of abdominal surgery: a study evaluating the HARM score in a European national cohort
Authors: Helgeland J , Skyrud K , Lindahl A K , Keller D , Augestad K M 
Published: April 2020

Abstract

Background
Reliable, easily accessible metrics of surgical quality are currently lacking. The HARM (HospitAl length of stay, Readmission and Mortality) score is a composite measure that has been validated across diverse surgical cohorts. The aim of this study was to validate the HARM score in a national population of patients undergoing abdominal surgery.

Methods
Data on all abdominal surgery in Norwegian hospitals from 2011 to 2017 were obtained from the Norwegian Patient Registry. Readmissions and 30-day postoperative complications as well as deaths in and out of hospital were evaluated. The HARM scoring algorithm was tested after adjustment by establishing a newly proposed length of stay score. The correlation between the HARM score and complications, as well as the ability of aggregated HARM scores to discriminate between hospitals, were analysed. Risk adjustment models were developed for nationwide hospital comparisons.

Results
The data consisted of 407 113 primary operations on 295 999 patients in 85 hospitals. The HARM score was associated with complications and complication severity (Goodman–Kruskal γ value 0·59). Surgical specialty was the dominating variable for risk adjustment. Based on 1-year data, the risk-adjusted score classified 16 hospitals as low HARM score and 16 as high HARM score of the 53 hospitals that had at least 30 operations.

Conclusion
The HARM score correlates with major outcomes and is associated with the presence and severity of complications. After risk adjustment, the HARM score discriminated strongly between hospitals in a European population of abdominal surgery.
Environmental policies, national culture, and stock price crash risk: Evidence from renewable energy firms
Authors: Yildiz Yilmaz , Karan Mehmet Baha 
Published: April 2020

AbstractThis study investigates the impact of country‐level environmental performance and national culture on the stock price crash risk of renewable energy firms. Employing a large sample of 626 renewable energy firms across 31 countries, we find a significant nonlinear relationship between country‐level environmental performance and crash risk. National culture dimensions are found to strongly predict the crash risk of renewable energy firms, particularly after the global financial crisis. On the contrary, national culture dimensions and environmental policies are observed to not exert any significance in explaining the crash risk of fossil fuel firms. Our results are robust with respect to alternative measures of stock price crash risk and the endogeneity of national culture dimensions. Overall, the findings of this paper contribute to the environmental economics literature by providing new evidence regarding the role of societal and environmental factors in explaining the stock price crash risk of energy firms.
Iron‐Based Nanozymes in Disease Diagnosis and Treatment
Authors: Shi Chu , Li Yan , Gu Ning 
Published: April 2020

AbstractIron‐based nanozymes are currently one of the few clinical inorganic nanoparticles for disease diagnosis and treatment. Overcoming the shortcomings of natural enzymes, such as easy inactivation and low yield, combined with their special nanometer properties and magnetic functions, iron‐based nanozymes have broad prospects in biomedicine. This minireview summarizes their preparation, biological activity, catalytic mechanism, and applications in diagnosis and treatment of diseases. Finally, challenges to their future development and the trends of iron‐based nanozymes are discussed. The purpose of this minireview is to better understand and reasonably speculate on the rational design of iron‐based nanozymes as an increasingly important new paradigm for diagnostics.
Effect of proximal balloon edge dilation technique for opening a side branch ostium in repetitive‐proximal optimizing technique sequence
Authors: Kume Teruyoshi , Murasato Yoshinobu , Yamada Ryotaro , Koyama Terumasa , Tamada Tomoko , Imai Koichiro , Okamoto Hiroshi , Enzan Ayano , Neishi Yoji , Uemura Shiro 
Published: April 2020

AbstractObjectiveThe purpose of this experimental bench test was to compare stent deformation, obstruction of stent struts at a jailed side branch (SB) ostium, and stent strut malapposition between SB inflation using proximal balloon edge dilation (PBED) technique and SB inflation using conventional balloon dilation in repetitive‐proximal optimizing technique (re‐POT) sequence.BackgroundThe second proximal optimizing technique (POT) procedure in the re‐POT sequence might increase obstruction of stent struts at a jailed SB ostium, because deformation of stent cells at the main branch (MB) occurred during SB inflation for opening the SB ostium.MethodsA fractal coronary bifurcation bench model made of flexible urethane was used, and crossover single‐stent implantation (Xience Sierra, Abbott Vascular, Santa Clara, CA, n = 12) was performed from the MB with the re‐POT sequence. During the re‐POT sequence, the jailing rate at the SB ostium assessed by videoscopy was compared between SB inflation using PBED technique (PBED group, n = 6) and SB inflation using conventional balloon dilation (conventional group, n = 6).ResultsThe jailing rate after the second POT procedure tended to be lower in the PBED group than in the conventional group (26 ± 12% vs. 34 ± 8%, p = .211), and the change in the jailing rate during the second POT procedure was significantly smaller in the PBED group than in the conventional group (4.8 ± 5.3% vs. 11.6 ± 3.5%, p = .026).ConclusionsIn the re‐POT sequence, the PBED technique with a short balloon for SB inflation might minimize worsening of the jailing rate at the SB ostium during the second POT procedure.
Carbon Nanotube‐Based Molecularly Imprinted Voltammetric Sensor for Selective Diuretic Analysis of Dialysate and Hemodialysis Wastewater
Authors: de Oliveira Gabriela F. , Hudari Felipe F. , Pereira Fabíola M. V. , Zanoni Maria V. B. , da Silva José L. 
Published: April 2020

AbstractA molecularly imprinted polymer (MIP)‐based electrochemical sensor was developed for the monitoring of hydrochlorothiazide (HCT) in dialysate and hemodialysis wastewater. The MIP was constructed by the electropolymerization of ortho‐phenylenediamine on multi‐walled carbon nanotube modified glassy carbon electrode surface. The experimental optimization was carried out by Plackett‐Burman design screening and central composite design. Through square wave voltammetry (SWV) analysis, the sensor presented linear response in the range of 5.0×10−6 to 1.0×10−4 mol L−1 (R=0.9995) and detection limit of 3.2×10−6 mol L−1. The film morphology was investigated by SEM, EDX and AFM, and the electrochemical response was confirmed by EIS. The MIP film exhibited excellent selectivity for HCT, rapid response and good practicability. The sensor was successfully applied for direct and selective determination of HCT in dialysate and hemodialysis wastewater samples with recovery rates ranging from 97 % to 102 % based on the standard addition method.
Redox Mediator‐Based Microbial Biosensors for Acute Water Toxicity Assessment: A Critical Review
Authors: Fang Deyu , Gao Guanyue , Yang Yajie , Wang Yu , Gao Lijuan , Zhi Jinfang 
Published: April 2020

AbstractWater toxicity assessment is of great importance for monitoring water quality and safeguarding ecological health. Microbial biosensors, which use microorganisms as the bioreceptor, offer a promising complementary method for water quality evaluation. The present Minireview has particular emphasis on microbial biosensors that use redox mediators as signal indicators and their performance for water acute toxicity assessment. The principles, fabrication methods, and recent developments of electrochemical microbial biosensors are systematically summarized. In addition, the application of microbial fuel cells in water biological oxygen demand and biotoxicity determination are also briefly introduced. The main hurdles that hinder the on‐site application of electrochemical microbial biosensors are discussed. With unceasing efforts on improvement of sensitivity and stability, electrochemical microbial biosensors are promising to play more crucial roles in water quality evaluation.