bluuebunny/crossref_metadata_2025_split huggingface dataset:
Race, Ethnicity, and Disparities in Rheumatology Educational Materials
Authors: Strait Adrienne , Graf Jonathan , Margaretten Mary , Yazdany Jinoos , Goglin Sarah 
Published: March 2021

ObjectiveTo characterize the representation of dark skin color in clinical images across 4 major rheumatology training resources.MethodsWe gathered images of patients with rheumatic diseases from the American College of Rheumatology Image Library, UpToDate, the New England Journal of Medicine Images in Clinical Medicine and Clinical Cases filtered by “Rheumatology,” and the 9th edition of Kelley's Textbook of Rheumatology. Investigators used Fitzpatrick's skin phototypes to independently code images depicting visible skin as “light” (skin types I to IV), “dark” (skin types V to VI), or “indeterminate.” The representation of dark skin in clinical images was compared to the representation of Asian, Native American, and Black individuals within the US Census population and within lupus cases nationally.ResultsOf the 1,043 patient images included in the study, 13.4% had dark skin, 84.0% light skin, and 2.6% indeterminate skin color. Dark skin was underrepresented significantly in rheumatology educational materials and lupus images when compared with the representation of Asian, Native American, and Black individuals within the US Census population (13.4% versus 20.6%; χ2 = 32.8, P < 0.001) and in published studies of patients with systemic lupus erythematous (22.6% versus 44.2%; χ2 = 20.0, P < 0.001).ConclusionDarker skin tones are significantly underrepresented in major rheumatology clinical image banks. Improving representation of racial and ethnic minorities in rheumatology education materials can better equip trainees to recognize and diagnose cutaneous manifestations of rheumatic diseases in these groups.
Graphene‐Assisted Synthesis of 2D Polyglycerols as Innovative Platforms for Multivalent Virus Interactions
Authors: Mohammadifar Ehsan , Ahmadi Vahid , Gholami Mohammad Fardin , Oehrl Alexander , Kolyvushko Oleksandr , Nie Chuanxiong , Donskyi Ievgen S. , Herziger Svenja , Radnik Jörg , Ludwig Kai , Böttcher Christoph , Rabe Jürgen P. , Osterrieder Klaus , Azab Walid , Haag Rainer , Adeli Mohsen 
Published: March 2021

Abstract2D nanomaterials have garnered widespread attention in biomedicine and bioengineering due to their unique physicochemical properties. However, poor functionality, low solubility, intrinsic toxicity, and nonspecific interactions at biointerfaces have hampered their application in vivo. Here, biocompatible polyglycerol units are crosslinked in two dimensions using a graphene‐assisted strategy leading to highly functional and water‐soluble polyglycerols nanosheets with 263 ± 53 nm and 2.7 ± 0.2 nm average lateral size and thickness, respectively. A single‐layer hyperbranched polyglycerol containing azide functional groups is covalently conjugated to the surface of a functional graphene template through pH‐sensitive linkers. Then, lateral crosslinking of polyglycerol units is carried out by loading tripropargylamine on the surface of graphene followed by lifting off this reagent for an on‐face click reaction. Subsequently, the polyglycerol nanosheets are detached from the surface of graphene by slight acidification and centrifugation and is sulfated to mimic heparin sulfate proteoglycans. To highlight the impact of the two‐dimensionality of the synthesized polyglycerol sulfate nanosheets at nanobiointerfaces, their efficiency with respect to herpes simplex virus type 1 and severe acute respiratory syndrome corona virus 2 inhibition is compared to their 3D nanogel analogs. Four times stronger in virus inhibition suggests that 2D polyglycerols are superior to their current 3D counterparts.
Printed Capacitive Sensors Based on Ionic Liquid/Metal‐Organic Framework Composites for Volatile Organic Compounds Detection
Authors: Fernandez Eduardo , G. Saiz Paula , Peřinka Nikola , Wuttke Stefan , Fernández de Luis Roberto 
Published: March 2021

AbstractIn this paper, the potential of 2D printing technologies to create thin film gas sensors from ionic liquid (IL)/metal–organic framework (MOF) composites is evaluated. To accomplish this, the MOF is synthesized solvothermally, and impregnated with the IL. The structure and basic properties of the IL/MOF composites are characterized using thermal, spectroscopic, and X‐ray diffraction techniques, and the resultant sensing capacity of the bulk material is evaluated by impedance spectroscopy. The IL/MOF systems are then integrated into a 2D printed silver capacitive circuit by spray and tested on a custom‐made gas flow apparatus. Exposure of the IL/MOF based sensors to water, acetone, and ethanol induces a repetitive variation of the capacitance (from 0.05 to 7 pF) that is dependent on the nature of the gas. IL/MOF based sensors can detect changes in concentrations in the range of 10k–100k ppm in less than a second. The conclusions of this work are the first steps towards the development of 2D printed sensors based on IL/MOF materials. Such materials offer countless possibilities to tailor the porosity, chemistry, selectivity, and electrical response to make the sensor suitable to detect the desired analyte.
Stack‐and‐Draw Applied to the Engineering of Multi‐Material Fibers with Non‐Cylindrical Profiles
Authors: Strutynski Clément , Meza Ricardo Alvarado , Teulé‐Gay Lionel , El‐Dib Georges , Poulon‐Quintin Angeline , Salvetat Jean‐Paul , Vellutini Luc , Dussauze Marc , Cardinal Thierry , Danto Sylvain 
Published: March 2021

AbstractHere, it is demonstrated that the stack‐and‐draw approach can be expanded to unusual materials association and profile geometries to generate fiber assemblies with unprecedented functionalities. This approach relies on the stacking of flat oxide glass slides into a preform, which is then thermally elongated into tens‐of‐meters‐long ribbon fibers with preserved cross‐section ratio. Fabrication methodology is introduced. In order to illustrate the versatility of the method, a panel of fibers with diverse geometries and functions is exposed, including glass‐only exposed‐core fibers for chemical sensing and, upon the insertion of metal electrodes, H‐shaped multi‐cavity structures and compact, glass‐metal fiber optical detectors applied to a gas analysis by means of fiber‐tip plasma spectroscopy. It is believed this new approach will offer an attractive, straightforward solution for designing innovative, complex multimaterial fiber platforms with enhanced functionalities.
Single Cell Bioprinting with Ultrashort Laser Pulses
Authors: Zhang Jun , Byers Patrick , Erben Amelie , Frank Christine , Schulte‐Spechtel Levin , Heymann Michael , Docheva Denitsa , Huber Heinz P. , Sudhop Stefanie , Clausen‐Schaumann Hauke 
Published: March 2021

AbstractTissue engineering requires the precise positioning of mammalian cells and biomaterials on substrate surfaces or in preprocessed scaffolds. Although the development of 2D and 3D bioprinting technologies has made substantial progress in recent years, precise, cell‐friendly, easy to use, and fast technologies for selecting and positioning mammalian cells with single cell precision are still in need. A new laser‐based bioprinting approach is therefore presented, which allows the selection of individual cells from complex cell mixtures based on morphology or fluorescence and their transfer onto a 2D target substrate or a preprocessed 3D scaffold with single cell precision and high cell viability (93–99% cell survival, depending on cell type and substrate). In addition to precise cell positioning, this approach can also be used for the generation of 3D structures by transferring and depositing multiple hydrogel droplets. By further automating and combining this approach with other 3D printing technologies, such as two‐photon stereolithography, it has a high potential of becoming a fast and versatile technology for the 2D and 3D bioprinting of mammalian cells with single cell resolution.
Two‐Dimensional Material‐Enhanced Flexible and Self‐Healable Photodetector for Large‐Area Photodetection
Authors: An Chunhua , Nie Fengmin , Zhang Rongjie , Ma Xinli , Wu Dahao , Sun Yang , Hu Xiaodong , Sun Dong , Pan Li , Liu Jing 
Published: March 2021

AbstractFlexible photodetectors are fundamental elements to develop flexible/wearable systems, which can be widely used for in situ health and environmental monitoring, human–machine interacting, flexible displaying, etc. However, the degraded performance or even malfunction under severe mechanical deformation and/or damage remains a key challenge for current flexible photodetectors. In this article, a flexible photodetector is developed with strong self‐healing capability and stable performance under large deformation. This photodetector is made of the 2D material self‐healing film by mixing 2D materials homogenously with the self‐healing polymer of imidazolium‐based norbornene polymerized with ionic liquids and counterions. The 2D material self‐healing films show enhanced light absorption, and thus, decent photoresponse as compared to the pure self‐healing film. The achieved photoresponse remains stable and even increases under small tensile strain within 150%, while decreases slightly under large tensile strain up to 1000%. Moreover, the photodetector not only can be fully recovered from repeated mechanical cuttings, but also presents excellent long‐term stability in ambient condition for 500 days without showing any obvious degraded performance. Furthermore, a large‐area 2D material self‐healing photodetection array is designed with adjustable pixel size, which successfully recognizes the patterns of “T”, “J”, and “U”.
A Wearable Body Condition Sensor System with Wireless Feedback Alarm Functions
Authors: Xu Kaichen , Fujita Yusuke , Lu Yuyao , Honda Satoko , Shiomi Mao , Arie Takayuki , Akita Seiji , Takei Kuniharu 
Published: March 2021

AbstractEmerging feedback systems based on tracking body conditions can save human lives. In particular, vulnerable populations such as disabled people, elderly, and infants often require special care. For example, the high global mortality of infants primarily owing to sudden infant death syndrome while sleeping makes request for extraordinary attentions in neonatal intensive care units or daily lives. Here, a versatile laser‐induced graphene (LIG)‐based integrated flexible sensor system, which can wirelessly monitor the sleeping postures, respiration rate, and diaper moisture with feedback alarm notifications, is reported. A tilt sensor based on confining a liquid metal droplet inside a cavity can track at least 18 slanting orientations. A rapid and scalable laser direct writing method realizes LIG patterning in both the in‐plane and out‐of‐plane configurations as well as the formation of nonstick conductive structures to the liquid metal. By rationally merging the LIG‐based tilt, strain, and humidity sensors on a thin flexible film, the multimodal sensor device is applied to a diaper as a real‐time feedback tracking system of the sleeping posture, respiration, and wetness toward secure and comfortable lives. User‐friendly interfaces, which incorporate alarming functions, provide timely feedback for caregivers tending to vulnerable populations with limited self‐care capabilities.
Antibiofouling Thin‐Film Nanocomposite Membranes for Sustainable Water Purification
Authors: Pang Lijuan , Meier‐Haack Jochen , Huang Shaolong , Qi Lu , Cui Hongzhi , Ruan Shuangchen , Zeng Yu‐Jia 
Published: March 2021

AbstractMembrane technology provides a reliable and powerful solution to combat the global water crisis by producing fresh water through sustainable desalination. However, the decline in system performance due to membrane biofouling is a limitation and significant efforts have been made to explore fouling control mechanisms and develop simple methods to inhibit or eliminate membrane fouling. Nanotechnology has increased the number of options for the development of antibiofouling membranes by incorporating nanoparticles within the polyamide layer to produce a thin‐film nanocomposite (TFN) structure. This review presents recent advances in the preparation of antifouling TFN membranes and incorporation of different nanoparticles into the design. The review also discusses the strategies and mechanisms for reducing membrane fouling and proposes a future outlook for the field.
Solvent‐Promoted Oxidation of Aromatic Alcohols/Aldehydes to Carboxylic Acids by a Laccase‐TEMPO System: Efficient Access to 2,5‐Furandicarboxylic Acid and 5‐Methyl‐2‐Pyrazinecarboxylic Acid
Authors: Cheng Ai‐Di , Zong Min‐Hua , Lu Guang‐Hui , Li Ning 
Published: March 2021

AbstractLaccase coupled with 2,2,6,6‐tetramethylpiperidinyl‐1‐oxy (TEMPO) is a well‐known catalytic system for the oxidation of alcohols to the carbonyl compounds. In this work, a simple yet effective solvent engineering strategy is developed to enable aromatic alcohols/aldehydes to be efficiently oxidized to carboxylic acids by a laccase‐TEMPO system. Citrate buffer (100–300 mm, pH 6) rather than the widely used acetate buffer (pH 4–5) proves to be optimal for this purpose. The roles of citrate are discussed in laccase‐TEMPO‐catalyzed synthesis of carboxylic acids. 5‐Hydroxymethylfurfural (HMF) of 200 mm is oxidized to 2,5‐furandicarboxylic acid (FDCA), a top‐value biobased chemical in the polymer industry, in 28 h with a yield of up to 97%. Of the 18 substrates examined, 11 alcohols are converted to target carboxylic acids with >90% yields by this method, with 2 alcohols giving >60% yields of carboxylic acids. Gram‐scale preparation of FDCA and 5‐methyl‐2‐pyrazinecarboxylic acid, an important drug intermediate, is demonstrated with total turnover numbers up to 110 000 for laccase and space‐time yields up to 1.0 g/(L•h). This chemoenzymatic approach may be a promising alternative to traditional chemical oxidations for the synthesis of carboxylic acids.
A Theoretical Evaluation of Possible N2 Reduction Mechanism on Mo2B2
Authors: Wang Jia , He Chaozheng , Huo Jinrong , Fu Ling , Zhao Chenxu 
Published: March 2021

Abstract2D MBene has similar properties to MXene, and it has received widespread attention as an efficient ammonia synthesis catalyst. Herein, the catalytic effect of 2D Mo2B2 applied to the electrochemical nitrogen reduction reaction (NRR) by the first principles calculation is studied. It is found that 2D Mo2B2 can form different adsorption structures which have different electronic properties, and active N2 molecules effectively. These different structures have different catalytic mechanism on the NRR process. In addition, the possibility of NRR reactions on these structures is explored and it is found that when N2 adsorbed obliquely on 2D Mo2B2, it has the lowest overpotential (0.34 V). This work provides important reference for exploring more excellent NRR catalysis in experiments and expands the application of transition metal borides in catalysis.
Comparative Study on the Performance of Different Lead‐Based and Lead‐Free Perovskite Solar Cells
Authors: Jayan K. Deepthi , Sebastian Varkey 
Published: March 2021

AbstractA comparative theoretical study on the performance of perovskite solar cells (PSCs) with methyl ammonium lead iodide (MAPbI3) and methyl ammonium germanium iodide (MAGeI3) as absorber layers is reported by modeling the solar cells for a number of electron transport materials (ETMs), hole transport materials, and back‐contact metals using solar cell capacitance simulator 1D tool. For MAPbI3 as the absorber layer, the best photovoltaic performance is observed for the configuration glass/fluorine‐doped tin oxide (FTO)/SnO2/MAPbI3/NiO/Au with a power conversion efficiency (PCE) of 20.58% and a fill factor (FF) of 68.34% and for MAGeI3, the configuration glass/FTO/SnO2/MAGeI3/CuO/Pd exhibits the best performance with a PCE of 13.12% and a FF of 68.29%. This study indicates that the low‐cost metal oxide SnO2 is a better substitute for the commonly used TiO2 as ETM, and the metal oxides like NiO and CuO provide a higher PCE for device configurations with MAPbI3 and MAGeI3, respectively, as the absorber layer. The low‐cost back‐contact metal Pd provides a better performance for MAGeI3‐based PSCs. This study also indicates that the nontoxic MAGeI3‐based PSCs can be used for commercial applications as they are more thermally stable than the MAPbI3‐based PSCs and provide an equally good quantum efficiency curve as that of MAPbI3‐based PSCs.
Visible‐light‐induced Reactions Driven by Photochemical Activity of Quinolinone and Coumarin Scaffolds
Authors: Vellakkaran Mari , Hong Sungwoo 
Published: March 2021

AbstractOrganic photocatalysis has garnered significant interest in the field of photochemistry because of its ability to generate active radical species under mild conditions via energy or electron transfer from the excited state of photosensitizers to organic molecules. Quinolinones and coumarins are privileged scaffolds that are widely distributed in natural products and pharmaceutical agents. Recently, quinolinones and coumarins have emerged as promising organic photosensitizers for a variety of chemical transformations. Significant advances in the development of synthetic methods via organic photocatalysis have elucidated their essential electronic properties, leading to the development of highly site‐selective synthetic methods. This mini‐review highlights recent innovative approaches to site‐selective C−H bond functionalization catalyzed by light‐absorbing quinolinone and coumarin scaffolds.
Lokale Deuterierung ermöglicht NMR‐Messung von Methylgruppen in Proteinen aus eukaryotischen und Zell‐freien Expressionssystemen
Authors: Dubey Abhinav , Stoyanov Nikolay , Viennet Thibault , Chhabra Sandeep , Elter Shantha , Borggräfe Jan , Viegas Aldino , Nowak Radosław P. , Burdzhiev Nikola , Petrov Ognyan , Fischer Eric S. , Etzkorn Manuel , Gelev Vladimir , Arthanari Haribabu 
Published: March 2021

AbstractGPCRs, Antikörper, Proteinkinasen und andere therapeutisch relevante Proteine stellen NMR‐Untersuchungen vor klare Herausforderungen, da die notwendige ortspezifische Isotopenmarkierung sowie Deuterierung in eukaryotischen Expressionsystemen stark limitiert ist. Wir beschreiben hier eine kostengünstige und einfache Methode, mit der Proteine mit markierten Leucin‐Methylgruppen in bakteriellen, eukaryotischen oder zell‐freien Expressionssystemen hergestellt werden können, ohne dass bestehende Expressionsprotokolle abgeändert werden müssen. Dafür werden Leucine stereo‐selektiv 13C‐markiert und deuteriert, was den Bedarf für eine Deuterierung des Restproteins abmildert. Die resultierenden verbesserten NMR‐spektroskopischen Eigenschaften werden detailliert mittels Forbidden Coherence Transfer (FTC)‐Experimenten und Simulationen beschrieben. Die Anwendung dieser Isotopenmarkierung wird anhand von zell‐freier Synthese von Bakteriorhodopsin und der Expression der RRM2‐Domäne von humanem RBM39 in Insektenzellen gezeigt.
Mechanochemical Prebiotic Peptide Bond Formation**
Authors: Stolar Tomislav , Grubešić Saša , Cindro Nikola , Meštrović Ernest , Užarević Krunoslav , Hernández José G. 
Published: March 2021

AbstractThe presence of amino acids on the prebiotic Earth, either stemming from endogenous chemical routes or delivered by meteorites, is consensually accepted. Prebiotically plausible pathways to peptides from inactivated amino acids are still unclear as most oligomerization approaches rely on thermodynamically disfavored reactions in solution. Now, a combination of prebiotically plausible minerals and mechanochemical activation enables the oligomerization of glycine at ambient temperature in the absence of water. Raising the reaction temperature increases the degree of oligomerization concomitantly with the formation of a commonly unwanted cyclic glycine dimer (DKP). However, DKP is a productive intermediate in the mechanochemical oligomerization of glycine. The findings of this research show that mechanochemical peptide bond formation is a dynamic process that provides alternative routes towards oligopeptides and establishes new synthetic approaches for prebiotic chemistry.
Stereoselektive gerichtete kationische Kaskaden ermöglicht durch molekulare Verankerung in Terpencyclasen
Authors: Schneider Andreas , Jegl Philipp , Hauer Bernhard 
Published: March 2021

AbstractKaskadenreaktionen haben sich als eine innovative Methode erwiesen, um den Aufbau komplexer Moleküle aus natürlich verfügbaren Vorläufern auf atom‐, zeit‐, arbeits‐ und kosteneffiziente Weise zu ermöglichen. In dieser Arbeit berichten wir über eine Strategie zur Kontrolle von kationischen Cyclisierungskaskaden, indem wir die Fähigkeit zur Verankerung von dynamischen Substraten im aktiven Zentrum von Terpencyclasen über designte Wasserstoffbrückenbindungen ausnutzen. Dadurch ist es möglich, “gerichtete” Cyclisierungen im Gegensatz zu bisher etablierten “Non‐Stop”‐Cyclisierungen (99:1) zu induzieren und die Termination der Kaskade an ansonsten katalytisch kaum zugänglichen Intermediaten zu prädestinieren. Mittels dieser Strategie sind wir in der Lage, einen effizienten Zugang zu natürlich weit verbreiteten Apocarotenoiden, wertvollen Aromen und Düften im Gramm‐Maßstab zu schaffen, wobei wir mehrstufige Syntheserouten durch einen einzigen Schritt mit herausragender Selektivität (>99.5 % ee) und hohen Ausbeuten (bis zu 89 %) ersetzen.
Unified Synthesis of Polycyclic Alkaloids by Complementary Carbonyl Activation**
Authors: He Guoli , List Benjamin , Christmann Mathias 
Published: March 2021

AbstractA complementary dual carbonyl activation strategy for the synthesis of polycyclic alkaloids has been developed. Successful applications include the synthesis of tetracyclic alkaloids harmalanine and harmalacinine, pentacyclic indoloquinolizidine alkaloid nortetoyobyrine, and octacyclic β‐carboline alkaloid peganumine A. The latter synthesis features a protecting‐group‐free assembly and an asymmetric disulfonimide‐catalyzed cyclization. Furthermore, formal syntheses of hirsutine, deplancheine, 10‐desbromoarborescidine A, and oxindole alkaloids rhynchophylline and isorhynchophylline have been achieved. Finally, a concise synthesis of berberine alkaloid ilicifoline B was completed.
Protein–Antibody Conjugates (PACs): A Plug‐and‐Play Strategy for Covalent Conjugation and Targeted Intracellular Delivery of Pristine Proteins
Authors: Liu Bin , Singh Khushboo , Gong Shuai , Canakci Mine , Osborne Barbara A. , Thayumanavan S. 
Published: March 2021

AbstractWe report here on protein–antibody conjugates (PACs) that are used for antibody‐directed delivery of protein therapeutics to specific cells. PACs have the potential to judiciously combine the merits of two prolific therapeutic approaches—biologics and antibody–drug conjugates. We utilize spherical polymer brushes to construct PACs using the combination of two simple and efficient functionally orthogonal click chemistries. In addition to the synthesis and characterization of these nanoparticles, we demonstrate that PACs are indeed capable of specifically targeting cells based on the presence of target antigen on the cell surface to deliver proteins. The potentially broad adaptability of PACs opens up new opportunities for targeted biologics in therapeutics and sensing.