bluuebunny/crossref_metadata_2025_split huggingface dataset:
Slow Colonic Transit in Systemic Sclerosis: An Objective Assessment of Risk Factors and Clinical Phenotype
Authors: Cheah Jenice X. , Perin Jamie , Volkmann Elizabeth R. , Hummers Laura K. , Pasricha Pankaj J. , Wigley Fredrick M. , McMahan Zsuzsanna H. 
Published: August 2021

ObjectiveUp to 50% of patients with systemic sclerosis (SSc) experience slow colonic transit, which may be associated with severe outcomes. Our objective, therefore, was to identify specific clinical features associated with slow colonic transit in SSc.MethodsSSc patients with gastrointestinal symptoms were prospectively enrolled and completed a scintigraphy‐based whole gut transit study. Clinical features were compared between patients with and without slow colonic transit in univariate and multivariable logistic regression analyses.ResultsForty‐eight of 100 patients (48%) in our cohort had slow colonic transit. In the univariate analyses, slow colonic transit was positively associated with female sex (odds ratio [OR] 12.61 [95% confidence interval (95% CI) 1.56–101.90]), telangiectasia (OR 4.00 [95% CI 1.32–12.10]), anticentromere antibodies (OR 3.25 [95% CI 1.25–8.44]), prior or current smoking (OR 2.56 [95% CI 1.06–6.21]), and a Medsger gastrointestinal severity score of ≥3 (OR 3.94 [95% CI 1.16–13.36]). Patients were less likely to have significant restriction on pulmonary function tests (OR 0.23 [95% CI 0.09–0.63]). In our multivariable model, the association between slow colonic transit and telangiectasia (OR 3.97 [95% CI 1.20–13.20]) and less restrictive lung disease on pulmonary function tests (OR 0.28 [95% CI 0.09–0.86]) remained statistically significant, though a trend with smoking remained (OR 2.16 [95% CI 0.82–5.75]). Interestingly, there were no significant associations between slow colonic transit and delayed transit in other regions of the gastrointestinal tract.ConclusionDistinct clinical features are associated with slow colonic transit in SSc. Such features may provide insight in risk stratification and the study of disease mechanism in more homogeneous subgroups.
Heterogeneous MXene/PS‐b‐P2VP Nanofluidic Membranes with Controllable Ion Transport for Osmotic Energy Conversion
Authors: Lin Xiangbin , Liu Pei , Xin Weiwen , Teng Yunfei , Chen Jianjun , Wu Yadong , Zhao Yifei , Kong Xiang‐Yu , Jiang Lei , Wen Liping 
Published: August 2021

AbstractMembrane‐based osmotic power harvesting is a strategy for sustainable power generation. 2D nanofluids with high ion conductivity and selectivity are emerging candidates for osmotic energy conversion. However, the ion diffusion under nanoconfinement is hindered by homogeneous 2D membranes with monotonic charge regulation and severe concentration polarization, which results in an undesirable power conversion performance. Here, an asymmetric nanochannel membrane with a two‐layered structure is reported, in which the angstrom‐scale channels of 2D transition metal carbides/nitrides (MXenes) act as a screening layer for controlling ion transport, and the nanoscale pores of the block copolymer (BCP) are the pH‐responsive arrays with an ordered nanovoid structure. The heterogeneous nanofluidic device exhibits an asymmetric charge distribution and enlarged 1D BCP porosity under acidic and alkaline conditions, respectively; this improves the gradient‐driven ion diffusion, allowing a high‐performance osmotic energy conversion with a power density of up to 6.74 W m−2 by mixing artificial river water and seawater. Experiments and theoretical simulations indicate that the tunable asymmetric heterostructure contributes to impairing the concentration polarization and enhancing the ion flux. This efficient osmotic energy generator can advance the fundamental understanding of the MXene‐based heterogeneous nanofluidic devices as a paradigm for membrane‐based energy conversion technologies.
Toward High‐Performance Dihydrophenazine‐Based Conjugated Microporous Polymer Cathodes for Dual‐Ion Batteries through Donor–Acceptor Structural Design
Authors: Ma Wenyan , Luo Lian‐Wei , Dong Peihua , Zheng Peiyun , Huang Xiuhua , Zhang Chong , Jiang Jia‐Xing , Cao Yong 
Published: August 2021

AbstractRecent studies have demonstrated that dihydrophenazine (Pz) with high redox‐reversibility and high theoretical capacity is an attractive building block to construct p‐type polymer cathodes for dual‐ion batteries. However, most reported Pz‐based polymer cathodes to date still suffer from low redox activity, slow kinetics, and short cycling life. Herein, a donor–acceptor (D–A) Pz‐based conjugated microporous polymer (TzPz) cathode is constructed by integrating the electron‐donating Pz unit and the electron‐withdrawing 2,4,6‐triphenyl‐1,3,5‐triazine (Tz) unit into a polymer chain. The D–A type structure enhances the polymer conjugation degree and decreases the band gap of TzPz, facilitating electron transportation along the polymer skeletons. Therefore the TzPz cathode for dual‐ion battery shows a high reversible capacity of 192 mAh g−1 at 0.2 A g−1 with excellent rate performance (108 mAh g−1 at 30 A g−1), which is much higher than that of its counterpart polymer BzPz produced from 1,3,5‐triphenylbenzene (Bz) and Pz (148 and 44 mAh g−1 at 0.2 and 10 A g−1, respectively). More importantly, the TzPz cathode also shows a long and stable cyclability of more than 10 000 cycles. These results demonstrate that the D–A structural design is an efficient strategy for developing high‐performance polymer cathodes for dual‐ion batteries.
Anisotropic Iridescence and Polarization Patterns in a Direct Ink Written Chiral Photonic Polymer
Authors: Sol Jeroen A. H. P. , Sentjens Henk , Yang Lanti , Grossiord Nadia , Schenning Albertus P. H. J. , Debije Michael G. 
Published: August 2021

AbstractThe iridescence of structural color and its polarization characteristics originate from the nanoscale organization of materials. A major challenge in materials science is generating the bright, lustrous hues seen in nature through nanoscale engineering, while simultaneously controlling interaction of the material with different light polarizations. In this work, a suitable chiral nematic liquid crystal elastomer ink is synthesized for direct ink writing, which self‐assembles into a chiral photonic structure. Tuning the writing direction and speed leads to the programmed formation of a slanted photonic axis, which exhibits atypical iridescence and polarization selectivity. After crosslinking, a freely programmable, chiroptical photonic polymer material is obtained. The strongly perspective‐dependent appearance of the material can function as specialized anticounterfeit markers, as optical elements in decorative iridescent coatings, or, as demonstrated here, in optically based signaling features.
Analytical Model of Micropyramidal Capacitive Pressure Sensors and Machine‐Learning‐Assisted Design
Authors: Ma Chao , Li Gang , Qin Longhui , Huang Weicheng , Zhang Hongrui , Liu Wenfeng , Dong Tianyu , Li Sheng‐Tao 
Published: August 2021

AbstractFlexible micro‐pyramidal capacitive pressure sensors provide a high‐level tunability, showing fascinating implications in various applications, such as advanced healthcare, protheses, and smart robots. In this work, analytical models for capacitive pressure sensors are reported based on micro‐pyramidal electrodes and dielectrics, which are confirmed by both finite element simulations and existing experimental results. The proposed models can be used to predict the pressure response in a wide dynamic range, which enables to efficiently analyze the pressure range, linearity, and multiple regimes of sensitivity for designing devices. Moreover, neural networks are introduced to approximate the pressure responses, and, in turn, to inversely design the parameters of the pressure sensors with a desired pressure response. The machine‐learning‐assisted design is able to find multiple designed parameters for the customization purpose, manifesting itself a powerful approach to customize the sensor performance.
Modeling of n‐Alkanes on Calcite/Dolomite by Molecular Dynamics Simulations and First‐Principles Calculations
Authors: Li Huifang , Vovusha Hakkim , Sharma Sitansh , Singh Nirpendra , Schwingenschlögl Udo 
Published: August 2021

AbstractUsing a combination of molecular dynamics simulations and first‐principles calculations, the interaction of n‐alkanes with calcite/dolomite is investigated. It is observed that the n‐alkane molecules align preferentially parallel to the interface, despite interaction by weak physisorption, and give rise to distinct adsorption layers. The ordering turns out to be more pronounced on calcite than dolomite due to a smaller average velocity of the n‐alkane molecules. The observations are explained in terms of adsorption energies and charge transfers. The results show that functionalization is no prerequisite of structural ordering and a distinct mass density profile perpendicular to the interface.
Tailoring Materials with Specific Wettability in Biomedical Engineering
Authors: Sun Lingyu , Guo Jiahui , Chen Hanxu , Zhang Dagan , Shang Luoran , Zhang Bing , Zhao Yuanjin 
Published: August 2021

AbstractAs a fundamental feature of solid surfaces, wettability is playing an increasingly important role in our daily life. Benefitting from the inspiration of biological paradigms and the development in manufacturing technology, numerous wettability materials with elaborately designed surface topology and chemical compositions have been fabricated. Based on these advances, wettability materials have found broad technological implications in various fields ranging from academy, industry, agriculture to biomedical engineering. Among them, the practical applications of wettability materials in biomedical‐related fields are receiving remarkable researches during the past decades because of the increasing attention to healthcare. In this review, the research progress of materials with specific wettability is discussed. After briefly introducing the underlying mechanisms, the fabrication strategies of artificial materials with specific wettability are described. The emphasis is put on the application progress of wettability biomaterials in biomedical engineering. The prospects for the future trend of wettability materials are also presented.
Regulating Local Electron Density of Iron Single Sites by Introducing Nitrogen Vacancies for Efficient Photo‐Fenton Process
Authors: Su Lina , Wang Pengfei , Ma Xiaoli , Wang Junhui , Zhan Sihui 
Published: August 2021

AbstractThe activity of heterogeneous photocatalytic H2O2 activation in Fenton‐like processes is closely related to the local electron density of reaction centre atoms. However, the recombination of electron‐hole pairs arising from random charge transfer greatly restricts the oriented electron delivery to active center. Here we show a defect engineered iron single atom photocatalyst (Fe1‐Nv/CN, single Fe atoms dispersed on carbon nitride with abundant nitrogen vacancies) for the activation of H2O2 under visible light irradiation. Based on DFT calculations and transient absorption spectroscopy results, the engineered nitrogen vacancies serve as the electron trap sites, which can directionally drive the electrons to concentrate on Fe atoms. The formation of highly concentrated electrons density at Fe sites significantly improves the H2O2 conversion efficiency. Therefore, the optimized single atom catalyst exhibiting a higher ciprofloxacin degradation activity, which was up to 18 times that of pristine CN.
Grotthuss Proton‐Conductive Covalent Organic Frameworks for Efficient Proton Pseudocapacitors
Authors: Yang Yi , Zhang Penghui , Hao Liqin , Cheng Peng , Chen Yao , Zhang Zhenjie 
Published: August 2021

AbstractHerein, we describe the synthesis of two highly crystalline, robust, hydrophilic covalent organic frameworks (COFs) that display intrinsic proton conduction by the Grotthuss mechanism. The enriched redox‐active azo groups in the COFs can undergo a proton‐coupled electron transfer reaction for energy storage, making the COFs ideal candidates for pseudocapacitance electrode materials. After in situ hybridization with carbon nanotubes, the composite exhibited a high three‐electrode specific capacitance of 440 F g−1at the current density of 0.5 A g−1, among the highest for COF‐based supercapacitors, and can retain 90 % capacitance even after 10 000 charge–discharge cycles. This is the first example using Grotthuss proton‐conductive organic materials to create pseudocapacitors that exhibited both high power density and energy density. The assembled asymmetric two‐electrode supercapacitor showed a maximum energy density of 71 Wh kg−1with a maximum power density of 42 kW kg−1, surpassing that of all reported COF‐based systems.
Towards Data‐Driven Design of Asymmetric Hydrogenation of Olefins: Database and Hierarchical Learning
Authors: Xu Li‐Cheng , Zhang Shuo‐Qing , Li Xin , Tang Miao‐Jiong , Xie Pei‐Pei , Hong Xin 
Published: August 2021

AbstractAsymmetric hydrogenation of olefins is one of the most powerful asymmetric transformations in molecular synthesis. Although several privileged catalyst scaffolds are available, the catalyst development for asymmetric hydrogenation is still a time‐ and resource‐consuming process due to the lack of predictive catalyst design strategy. Targeting the data‐driven design of asymmetric catalysis, we herein report the development of a standardized database that contains the detailed information of over 12000 literature asymmetric hydrogenations of olefins. This database provides a valuable platform for the machine learning applications in asymmetric catalysis. Based on this database, we developed a hierarchical learning approach to achieve predictive machine leaning model using only dozens of enantioselectivity data with the target olefin, which offers a useful solution for the few‐shot learning problem and will facilitate the reaction optimization with new olefin substrate in catalysis screening.
Optically transparent bio‐based polyamides with microcellular foaming properties derived from renewable difunctional aminoamides
Authors: Ranganathan Palraj , Chen Yu‐Hao , Rwei Syang‐Peng , Lee Yi‐Huan 
Published: August 2021

AbstractA green approach for the synthesis of bio‐based polyamides (PAs) with a new macromolecular structure was developed. These bio‐based PAs were synthesized by solvent and catalyst‐free polycondensation combining fatty dimer acid Pripol™ 1009 with new difunctional aminoamides (DAAs). The later DAAs building blocks were synthesized by aminolysis of renewable dimethyl sebacate (DMS) and dimethyl adipate (DMA) with three different aliphatic diamines having diverse chain lengths, 2, 4, and 6 carbons. Bio‐based PAs showedMwup to 30,581 g/mol, initial thermal degradation over 380°C,Tmfrom 168.3–202.4°C,Tgfrom 28.3–37.5°C, strain from 36.4 ± 4.0–313.5 ± 2.0%, and tensile strength up to 27.4 ± 0.1 MPa. Interestingly, all the PAs films had excellent optical transparency with cut‐off wavelengths of 276.0–283.0 nm, transmittance from 82.7%–90.7% at 600 nm. As a proof‐of‐concept of their usage, one of the PA was shown to be form microcellular foam by the green scCO2method. The foams possessed uniform (cell size; 40 μm, foam density; 0.265 g/cm3, expansion rate; 7.2) and bimodal (cell size; 24/38 μm, foam density; 0.302 g/cm3, expansion rate; 6.5) cell textures depending on their foaming temperatures. This is the first report of bio‐based PA foams and transparent films manufacturing without toxic solvents.
Fintiamin: A diketopiperazine from the marine sponge‐derived fungus Eurotium sp.
Authors: Elsebai Mahmoud F. , Schoeder Clara T. , Müller Christa E. 
Published: August 2021

AbstractThe fungus Eurotium sp., derived from the marine sponge Ircinia variabilis, was found to produce a diketopiperazine–indole alkaloid that we named fintiamin (1). Structural elucidation of 1 was achieved by extensive spectroscopic analysis including nuclear magnetic resonance spectroscopy and mass spectrometry. Compound 1 is a lipophilic terpenoid–dipeptide hybrid molecule that shows affinity for the cannabinoid CB1 receptor at low micromolar concentrations. Docking studies based on previous X‐ray structures provide a plausible binding pose for compound 1 in the orthosteric binding site of the CB1 receptor.
Time‐domain signal averaging to improve microparticles detection and enumeration accuracy in a microfluidic impedance cytometer
Authors: Ashley Brandon K. , Hassan Umer 
Published: August 2021

AbstractMicrofluidic impedance cytometry is a powerful system to measure micro and nano‐sized particles and is routinely used in point‐of‐care disease diagnostics and other biomedical applications. However, small objects near a sensor's detection limit are plagued with relatively significant background noise and are difficult to identify for every case. While many data processing techniques can be utilized to reduce noise and improve signal quality, frequently they are still inadequate to push sensor detection limits. Here, we report the first demonstration of a novel signal averaging algorithm effective in noise reduction of microfluidic impedance cytometry data, improving enumeration accuracy, and reducing detection limits. Our device uses a 22 µm tall × 100 µm wide (with 30 µm wide focused aperture) microchannel and gold coplanar microelectrodes that generate an electric field, recording bipolar pulses from polystyrene microparticles flowing through the channel. In addition to outlining a modified moving signal averaging technique theoretically and with a model data set, we also performed a compendium of characterization experiments including variations in flow rate, input voltage, and particle size. Multivariate metrics from each experiment are compared including signal amplitude, pulse width, background noise, and signal‐to‐noise ratio (SNR). Incorporating our technique resulted in improved SNR and counting accuracy across all experiments conducted, and the limit of detection improved from 5 to 1 µm particles without modifying microchannel dimensions. Succeeding this, we envision implementing our modified moving average technique to develop next‐generation microfluidic impedance cytometry devices with an expanded dynamic range and improved enumeration accuracy. This can be exceedingly useful for many biomedical applications, such as infectious disease diagnostics where devices may enumerate larger‐scale immune cells alongside sub‐micron bacterium in the same sample.
Advances in mapping the epigenetic modifications of 5‐methylcytosine (5mC), N6‐methyladenine (6mA), and N4‐methylcytosine (4mC)
Authors: Lv Hao , Dao Fu‐Ying , Zhang Dan , Yang Hui , Lin Hao 
Published: August 2021

AbstractDNA modification plays a pivotal role in regulating gene expression in cell development. As prevalent markers on DNA, 5‐methylcytosine (5mC), N6‐methyladenine (6mA), and N4‐methylcytosine (4mC) can be recognized by specific methyltransferases, facilitating cellular defense and the versatile regulation of gene expression in eukaryotes and prokaryotes. Recent advances in DNA sequencing technology have permitted the positions of different modifications to be resolved at the genome‐wide scale, which has led to the discovery of several novel insights into the complexity and functions of multiple methylations. In this review, we summarize differences in the various mapping approaches and discuss their pros and cons with respect to their relative read depths, speeds, and costs. We also discuss the development of future sequencing technologies and strategies for improving the detection resolution of current sequencing technologies. Lastly, we speculate on the potentially instrumental role that these sequencing technologies might play in future research.
In vivo cleavage of solubility tags as a tool to enhance the levels of soluble recombinant proteins in Escherichia coli
Authors: Silva Filipe S. R. , Santos Sara P. O. , Meyer Roberto , Silva Eduardo S. , Pinheiro Carina S. , Alcantara‐Neves Neuza M. , Pacheco Luis G. C. 
Published: August 2021

AbstractRecombinant proteins are generally fused with solubility enhancer tags to improve the folding and solubility of the target protein of interest. However, the fusion protein strategy usually requires expensive proteases to perform in vitro proteolysis and additional chromatographic steps to obtain tag‐free recombinant proteins. Expression systems based on intracellular processing of solubility tags in Escherichia coli, through co‐expression of a site‐specific protease, simplify the recombinant protein purification process, and promote the screening of molecules that fail to remain soluble after tag removal. High yields of soluble target proteins have already been achieved using these protease co‐expression systems. Herein, we review approaches for controlled intracellular processing systems tailored to produce soluble untagged proteins in E. coli. We discuss the different genetic systems available for intracellular processing of recombinant proteins regarding system design features, advantages, and limitations of the various strategies.
The persistent median artery and its vascular patterns: A meta‐analysis of 10,394 subjects
Authors: Solewski Bernard , Lis Maciej , Pękala Jakub R. , Brzegowy Karolina , Lauritzen Sigurd S. , Hołda Mateusz K. , Walocha Jerzy A. , Tomaszewski Krzysztof A. , Pękala Przemysław A. , Koziej Mateusz 
Published: August 2021

AbstractThe presence of a persistent median artery (PMA) has been implicated in the development of compression neuropathies and surgical complications. Due to the large variability in the prevalence of the PMA and its subtypes in the literature, more awareness of its anatomy is needed. The aim of our meta‐analysis was to find the pooled prevalence of the antebrachial and palmar persistent median arteries. An extensive search through the major databases was performed to identify all articles and references matching our inclusion criteria. The extracted data included methods of investigation, prevalence of the PMA, anatomical subtype (antebrachial, palmar), side, sex, laterality, and ethnicity. A total of 64 studies (n = 10,394 hands) were included in this meta‐analysis. An antebrachial pattern was revealed to be more prevalent than a palmar pattern (34.0% vs. 8.6%). A palmar PMA was reported in 2.6% of patients undergoing surgery for carpal tunnel syndrome when compared to cadaveric studies of adult patients in which the prevalence was 8.6%. Both patterns of PMA are prevalent in a considerable portion of the general population. As the estimated prevalence of the PMA was found to be significantly lower in patients undergoing surgery for carpal tunnel syndrome than those reported in cadaveric studies, its etiological contribution to carpal tunnel syndrome is questionable. Surgeons operating on the forearm and carpal tunnel should understand the anatomy and surgical implications of the PMA and its anatomical patterns.