bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bionanoscale Recognition Underlies Cell Fate and Therapy
Authors: Sun Shan , Deng Peng , Mu Li , Hu Xiangang , Guo Shuqing 
Published: September 2021

AbstractUnderstanding the bionanoscale recognition of nanostructured architectures is critical to the design and application of nanomaterials, but the related information is not well understood. In this study, it is found that bionanoscale recognition underlies cell fate and therapy. For example, 1T phase (octahedral coordination) monolayer MoS2 exhibits a markedly stronger affinity for fibronectin than the 2H structure (triangular prism coordination) and promotes cell spreading and differentiation. The van der Waals energy and increased turn components contribute to the high adhesion of fibronectin onto the 1T‐MoS2 structure. 1T‐MoS2 exhibits a significantly stronger affinity (KD, 6.59 × 10−7 m) for liposomes than 2H‐MoS2 (1.21 × 10−6 m) due to strong hydrophobic interactions. The existence of octahedrally coordinated atomic structures that improve cell viability by enhancing the neurite length is first proven by random forest and structural equation models. Consequently, octahedral coordination disaggregates α‐synuclein (e.g., by decreasing β‐sheets and increasing coil structures) and protects cells and hosts against Parkinson's disease. As a proof‐of‐principle demonstration, these findings indicate that bionanoscale recognition underlies the design of biomaterials and cell therapeutics.
Biomimetic Ultraflexible Piezoresistive Flow Sensor Based on Graphene Nanosheets and PVA Hydrogel
Authors: Abolpour Moshizi Sajad , Moradi Hamed , Wu Shuying , Han Zhao Jun , Razmjou Amir , Asadnia Mohsen 
Published: September 2021

AbstractFlow sensors play a critical role in monitoring flow parameters, including rate, velocity, direction, and rotation frequency. In this paper, inspired by biological hair cells in the human vestibular system, an innovative flow sensor is developed based on polyvinyl alcohol (PVA) hydrogel nanocomposites with a maze‐like network of vertically grown graphene nanosheets (VGNs). The VGNs/PVA hydrogel absorbs a copious amount of water when immersed in water, making the sensor highly sensitive to tiny stimuli underwater. The sensor demonstrates a high sensitivity (5.755 mV (mm s−1)−1) and extremely low velocity detection (0.022 mm s−1). It also reveals outstanding performance in detecting low‐frequency oscillatory flows down to 0.1 Hz, which make it suitable for many biomedical applications. As one of the potential applications of the sensor, it exhibits excellent performance in mimicking various physiological conditions of vestibular hair cells. To explain the experimental results, a complete finite element simulation is developed to model the piezoresistive effect of VGNs/PVA thin film structure. This is the first attempt to develop hydrogel–graphene nanosheet‐based flow sensors, which creates the closest artificial sensor to vestibular hair cells. This miniaturized hair cell sensor paves the way for utilizing hydrogels to develop next‐generation of ultrasensitive flow sensors for biomedical applications.
Mechanochemical Transformation of CF3 Group: Synthesis of Amides and Schiff Bases
Authors: Mkrtchyan Satenik , Jakubczyk Michał , Lanka Suneel , Yar Muhammad , Ayub Khurshid , Shkoor Mohanad , Pittelkow Michael , Iaroshenko Viktor O. 
Published: September 2021

AbstractWe communicate two mild, solvent‐free mechanochemical coupling transformations of CF3 group with nitro compounds into amides or Schiff bases employing Ytterbia as a catalyst. This process proceeds via C−F bond activation, accompanied with utilisation of Si‐based reductants/oxygen scavengers – reductants of the nitro group. The scope and limitations of the disclosed methodologies are thoroughly studied. To the best of our knowledge, this work is the first example of mechanical energy promoted transformation of the inert CF3 group into other functionalities.magnified image
Recent Advances in Transformations Involving Electron‐Rich Alkenes: Functionalization, Cyclization, and Cross‐Metathesis Reactions
Authors: Zhou Fei , Li Meng , Jiang Huanfeng , Wu Wanqing 
Published: September 2021

AbstractDue to the versatile reactivity and molecular complexity, as well as diversity, electron‐rich alkenes bearing nitrogen, oxygen, or sulfur atoms have been regarded as versatile reagents in organic synthesis. This review mainly focuses on the recent advances in the reaction development of electron‐rich alkenes since 2000, including mono‐/difunctionalization reactions, cyclization reactions, and cross‐metathesis reactions. Numerous protocols enabling facile and efficient transformations of electron‐rich alkenes to valuable compounds have been developed, which are discussed with special emphasis placed on the mechanistic aspects and the synthetic utilities. We hope that this review will help inspire future studies and promote developments in this area.magnified image
Conservation agriculture can help the South American Andean region achieve food security
Authors: Barrera Víctor H. , Delgado Jorge A. , Alwang Jeffrey R. 
Published: September 2021

AbstractThe Andean region of Ecuador is dominated by small‐scale agriculture on steep slopes vulnerable to erosion, soil degradation, and subsequent productivity loss. Soil erosion rates exceed the average rate of soil formation by 9–286 times, making current agricultural practices in the region unsustainable, and threatening to increase food insecurity. The projected effects of a changing climate vary across the Andean region, with higher precipitation and erosion rates projected for some areas. However, even in areas where the precipitation rates are expected to be lower, the projected erosion rates will still be unsustainable. Research on conservation agriculture (CA) practices conducted from 2008 to 2017 in the highlands of Ecuador suggests that yields and cost savings ultimately make several CA production systems profitable compared to conventional practices. In the very short term, large gains did not emerge, and the best that could be said about CA is that it did not reduce productivity. Over the medium term, improvements in soil health (lower erosion) led to higher profitability that made the practices more profitable than conventional practices over the entire rotation. However, adoption of these alternatives by local producers, even in research areas, is low. Lack of public or private agricultural extension contributes to slow diffusion of new technology and best management practices in the region. There is a need to develop improved communication with local farmers to more effectively relay how CA protects the soil, mitigates degradation, and provides a means to achieve food security and avoid a humanitarian crisis.
Health and safety risk perceptions and needs of app‐based drivers during COVID‐19
Authors: Beckman Kerry L. , Monsey Lily M. , Archer Megan M. , Errett Nicole A. , Bostrom Ann , Baker Marissa G. 
Published: September 2021

AbstractBackgroundApp‐based drivers face work disruptions and infection risk during a pandemic due to the nature of their work, interactions with the public, and lack of workplace protections. Limited occupational health research has focused on their experiences.MethodsWe surveyed 100 app‐based drivers in Seattle, WA to assess risk perceptions, supports, and controls received from the company that employs them, sources of trust, stress, job satisfaction, COVID‐19 infection status, and how the pandemic had changed their work hours. Data were summarized descriptively and with simple regression models. We complemented this with qualitative interviews to better understand controls and policies enacted during COVID‐19, and barriers and facilitators to their implementation.ResultsDrivers expressed very high levels of concern for exposure and infection (86%–97% were “very concerned” for all scenarios). Only 31% of drivers reported receiving an appropriate mask from the company for which they drive. Stress (assessed via PSS‐4) was significantly higher in drivers who reported having had COVID‐19, and also significantly higher in respondents with lower reported job satisfaction. Informants frequently identified supports such as unemployment benefits and peer outreach among the driver community as ways to ensure that drivers could access available benefits during COVID‐19.ConclusionsApp‐based drivers received few protections from the company that employed them, and had high fear of exposure and infection at work. There is increased need for health‐supportive policies and protections for app‐based drivers. The most effective occupational and public health regulations would cover employees who may not have a traditional employer–employee relationship.
A truncating NRIP1 variant in an Arabic family with congenital anomalies of the kidneys and urinary tract
Authors: Zheng Bixia , Wang Chunyan , Seltzsam Steve , Schneider Sophia , Schierbaum Luca , Wu Wilfred , Dai Rufeng , Connaughton Dervla M. , Nakayama Makiko , Mann Nina , Bauer Stuart B. , Awad Hazem S. , Eid Loai A. , Tasic Velibor , Shril Shirlee , Hildebrandt Friedhelm 
Published: September 2021

AbstractCongenital anomalies of the kidneys and urinary tract (CAKUT) constitute the most common cause of early‐onset chronic kidney disease. In a previous study, we identified a heterozygous truncating variant in nuclear receptor‐interacting protein 1 (NRIP1) as CAKUT causing via dysregulation of retinoic acid signaling. This large family remains the only family with NRIP1 variant reported so far. Here, we describe one additional CAKUT family with a truncating variant in NRIP1. By whole‐exome sequencing, we identified one heterozygous frameshift variant (p.Asn676Lysfs*27) in an isolated CAKUT patient with bilateral hydroureteronephrosis and right grade V vesicoureteral reflux (VUR) and in the affected father with left renal hypoplasia. The variant is present twice in a heterozygous state in the gnomAD database of 125,000 control individuals. We report the second CAKUT family with a truncating variant in NRIP1, confirming that loss‐of‐function mutations in NRIP1 are a novel monogenic cause of human autosomal dominant CAKUT.
Design of Persistent and Stable Porous Radical Polymers by Electronic Isolation Strategy
Authors: Su Yan , Chen Zhongxin , Tang Xiaohui , Xu Hong , Zhang Yujian , Gu Cheng 
Published: September 2021

AbstractConjugated organic radical polymers with stable radical features are difficult to design because the π conjugation in the polymer backbones makes the radicals readily delocalize and tend to undergo covalent bonding processes. In this work, we report an electronic isolation strategy to design stable porous radical polymers by homocoupling reaction from a meta‐position active monomer. The meta linkage ensures less conjugation in the polymer skeletons, localizes the resonant radicals, and prevents them from recombination. The resulting porous radical polymer exhibits exceptional radical characters with ultralow band gap of 0.68 eV, strong yet extended UV/Vis‐NIR absorption up to 1800 nm, and high spin density. The above features make the polymer very promising in the photothermal conversion with record‐high photothermal temperature increment of ≈∼240 °C and striking solar‐driven water evaporation efficiency of 96.8 %. Our results demonstrate the feasibility of electronic isolation of radicals for producing outstanding photothermal materials.
Atomic Cation‐Vacancy Engineering of NiFe‐Layered Double Hydroxides for Improved Activity and Stability towards the Oxygen Evolution Reaction
Authors: Peng Lishan , Yang Na , Yang Yuqi , Wang Qing , Xie Xiaoying , Sun‐Waterhouse Dongxiao , Shang Lu , Zhang Tierui , Waterhouse Geoffrey I. N. 
Published: September 2021

AbstractNiFe‐layered double hydroxides (NiFe‐LDH) are among the most active catalysts developed to date for the oxygen evolution reaction (OER) in alkaline media, though their long‐term OER stability remains unsatisfactory. Herein, we reveal that the stability degradation of NiFe‐LDH catalysts during alkaline OER results from a decreased number of active sites and undesirable phase segregation to form NiOOH and FeOOH, with metal dissolution underpinning both of these deactivation mechanisms. Further, we demonstrate that the introduction of cation‐vacancies in the basal plane of NiFe LDH is an effective approach for achieving both high catalyst activity and stability during OER. The strengthened binding energy between the metals and oxygen in the LDH sheets, together with reduced lattice distortions, both realized by the rational introduction of cation vacancies, drastically mitigate metal dissolution from NiFe‐LDH under high oxidation potentials, resulting in the improved long‐term OER stability. In addition, the cation vacancies (especially M3+ vacancies) accelerate the evolution of surface γ‐(NiFe)OOH phases, thereby boosting the OER activity. The present study highlights that tailoring atomic cation‐vacancies is an important strategy for the development of active and stable OER electrocatalysts.
The Significance of Properly Reporting Turnover Frequency in Electrocatalysis Research
Authors: Anantharaj Sengeni , Karthik Pitchiah Esakki , Noda Suguru 
Published: September 2021

AbstractFor decades, turnover frequency (TOF) has served as an accurate descriptor of the intrinsic activity of a catalyst, including those in electrocatalytic reactions involving both fuel generation and fuel consumption. Unfortunately, in most of the recent reports in this area, TOF is often not properly reported or not reported at all, in contrast to the overpotentials at a benchmarking current density. The current density is significant in determining the apparent activity, but it is affected by catalyst‐centric parasitic reactions, electrolyte‐centric competing reactions, and capacitance. Luckily, a properly calculated TOF can precisely give the intrinsic activity free from these phenomena in electrocatalysis. In this Viewpoint we ask: 1) What makes the commonly used activity markers unsuitable for intrinsic activity determination? 2) How can TOF reflect the intrinsic activity? 3) Why is TOF still underused in electrocatalysis? 4) What methods are used in TOF determination? and 5) What is essential in the more accurate calculation of TOF? Finally, the significance of normalizing TOF by Faradaic efficiency (FE) is stressed and we give our views on the development of universal analytical tools to determine the exact number of active sites and real surface area for all kinds of materials.
Unexpected Reactions of α,β‐Unsaturated Fatty Acids Provide Insight into the Mechanisms of CYP152 Peroxygenases
Authors: Jiang Yuanyuan , Peng Wei , Li Zhong , You Cai , Zhao Yue , Tang Dandan , Wang Binju , Li Shengying 
Published: September 2021

AbstractCYP152 peroxygenases catalyze decarboxylation and hydroxylation of fatty acids using H2O2 as cofactor. To understand the molecular basis for the chemo‐ and regioselectivity of these unique P450 enzymes, we analyze the activities of three CYP152 peroxygenases (OleTJE, P450SPα, P450BSβ) towards cis‐ and trans‐dodecenoic acids as substrate probes. The unexpected 6S‐hydroxylation of the trans‐isomer and 4R‐hydroxylation of the cis‐isomer by OleTJE, and molecular docking results suggest that the unprecedented selectivity is due to OleTJE’s preference of C2−C3 cis‐configuration. In addition to the common epoxide products, undecanal is the unexpected major product of P450SPα and P450BSβ regardless of the cis/trans‐configuration of substrates. The combined H218O2 tracing experiments, MD simulations, and QM/MM calculations unravel an unusual mechanism for Compound I‐mediated aldehyde formation in which the active site water derived from H2O2 activation is involved in the generation of a four‐membered ring lactone intermediate. These findings provide new insights into the unusual mechanisms of CYP152 peroxygenases.
Sn2PO4I: An Excellent Birefringent Material with Giant Optical Anisotropy in Non π‐Conjugated Phosphate
Authors: Guo Jingyu , Tudi Abudukadi , Han Shujuan , Yang Zhihua , Pan Shilie 
Published: September 2021

AbstractExploring non π‐conjugated phosphate birefringent crystal with a large birefringence has been a great challenge. Herein, based on the unique two‐dimensional layered structure in KBe2BO3F2 (KBBF), two new compounds, Sn2PO4I and Sn2BO3I, were designed and synthesized successfully, maintaining the layer structural feature and enhancing the optical anisotropy of crystals. In particular, the birefringence of Sn2PO4I is larger than or equal to 0.664 @546 nm, which is largest among the reported borates and phosphates, even surpassing commercial birefringent crystals YVO4 and TiO2. This work indicates that a breakthrough in birefringence of inorganic compound was achieved. Also, it provides a guiding idea for exploring large birefringence materials in the future.
Molten Salt Electrochemical Modulation of Iron–Carbon–Nitrogen for Lithium–Sulfur Batteries
Authors: Weng Wei , Xiao Juanxiu , Shen Yijun , Liang Xinxin , Lv Teng , Xiao Wei 
Published: September 2021

AbstractSulfur hosts with rationally designed chemistry to confine and convert lithium polysulfides are of prime importance for high‐performance lithium–sulfur batteries. A molten salt electrochemical modulation of iron–carbon–nitrogen is herein demonstrated as formation of hollow nitrogen‐doped carbon with grafted Fe3C nanoparticles (Fe3C@C@Fe3C), which is rationalized as an excellent sulfur host for lithium‐sulfur batteries. Fe3C over nitrogen‐doped carbon contributes to enhanced adsorption and catalytic conversion of lithium polysulfides. The sulfur‐loaded Fe3C@C@Fe3C electrodes hence show a high capacity, good cyclic stability, and enhanced rate performance. This work highlights the unique chemistry of metal carbides on facilitating adsorption–conversion process of lithium polysulfides, and also extends the scope of molten salt electrolysis to elaboration of energy materials.
Dynamic Control of Sacrificial Bond Transformation in the Fe−N−C Single‐Atom Catalyst for Molecular Oxygen Reduction
Authors: Yu Li , Li Yuchan , Ruan Yuefei 
Published: September 2021

AbstractAtomically dispersed metal‐nitrogen sites show great prospect for the oxygen reduction reaction (ORR), whereas the unsatisfactory adsorption‐desorption behaviors of oxygenated intermediates on the metal centers impede improvement of the ORR performance. We propose a new conceptual strategy of introducing sacrificial bonds to remold the local coordination of Fe−Nx sites, via controlling the dynamic transformation of the Fe−S bonds in the Fe−N−C single‐atom catalyst. Spectroscopic and theoretical results reveal that the selective cleavage of the sacrificial Fe−S bonds induces the incorporation of the electron‐withdrawing oxidized sulfur on the Fe centers. The newly functionalized moieties endow the catalyst with superior ORR activity and remarkable stability, owing to the reduced electron localization around the Fe centers facilitating the desorption of ORR intermediates. These findings provide a unique perspective for precisely controlling the coordination structure of single‐atom materials to optimize their activity.
Ring Expansion Fluorination of Unactivated Cyclopropanes Mediated by a New Monofluoroiodane(III) Reagent
Authors: Ren Jing , Du Feng‐Huan , Jia Meng‐Cheng , Hu Ze‐Nan , Chen Ze , Zhang Chi 
Published: September 2021

AbstractHerein, we report a new strategy for carbon−carbon bond scission and intramolecular ring expansion fluorination of unactivated cyclopropanes, which was accomplished with a new hypervalent fluoroiodane(III) reagent1. This novel method delivers medicinally relevant 4‐fully substituted fluoropiperidines in moderate to high yields with excellent regio‐ and diastereoselectivity. Reagent1, which has an N‐acetylbenziodazole framework, was readily synthesized via three steps in 76 % overall yield and was characterized by NMR spectroscopy and X‐ray crystallography. Owing to the presence of a secondary I⋅⋅⋅O bonding interaction between the λ3‐iodane atom and the carbonyl oxygen of the acetyl group of the N‐acetylbenziodazole framework,1has excellent stability and can be stored at ambient temperature for 6 months without any detectable decomposition. Density functional theory calculations and experimental studies showed that the reaction proceeds via a carbocation intermediate that readily combines with a fluoride ion to generate the product.
Modulating Tri‐Mode Emission for Single‐Component White Organic Afterglow
Authors: Jin Jibiao , Xue Peiran , Zhang Longyan , Jiang He , Wang Wuji , Yang Qingqing , Tao Ye , Zheng Chao , Chen Runfeng , Huang Wei 
Published: September 2021

AbstractAchieving single‐component white organic afterglow remains a great challenge owing to the difficulties in simultaneously supporting long‐lived emissions from varied excited states of a molecule for complementary afterglow. Here, an extraordinary tri‐mode emission from the radiative decays of singlet (S1), triplet (T1), and stabilized triplet (T1*) excited states was proposed to afford white afterglow through modulating the singlet–triplet splitting energy (ΔEST) and exciton trapping depth (ETD). Low‐lying T1* for yellow afterglow was constructed by H‐aggregation engineering with large ETD and trace isomer doping, while high‐lying T1 and S1 for blue afterglow with thermally activated emission feature were realized by reducing ΔEST through donor–acceptor molecular design. Therefore, the single‐component white afterglow with high efficiency of 14.1 % and a lifetime of 0.61 s was achieved by rationally regulating the afterglow intensity ratios of complementary emissions from S1, T1, and T1*.
Anion–Anion Chemistry with Mass‐Selected Molecular Fragments on Surfaces
Authors: Yang Fangshun , Behrend K. Antonio , Knorke Harald , Rohdenburg Markus , Charvat Ales , Jenne Carsten , Abel Bernd , Warneke Jonas 
Published: September 2021

AbstractWhile reactions between ions and neutral molecules in the gas phase have been studied extensively, reactions between molecular ions of same polarity remain relatively unexplored. Herein we show that reactions between fragment ions generated in the gas phase and molecular ions of the same polarity are possible by soft‐landing of both reagents on surfaces. The reactive [B12I11]1− anion was deposited on a surface layer built up by landing the generally unreactive [B12I12]2−. Ex‐situ analysis of the generated material shows that [B24I23]3− was formed. A computational study shows that the product is metastable in the gas phase, but a charge‐balanced environment of a grounded surface may stabilize the triply charged product, as suggested by model calculations. This opens new opportunities for the generation of highly charged clusters using unconventional building blocks from the gas phase.
Chemical and Enzymatic Synthesis of Sialylated Glycoforms of Human Erythropoietin
Authors: Hessefort Hendrik , Gross Angelina , Seeleithner Simone , Hessefort Markus , Kirsch Tanja , Perkams Lukas , Bundgaard Klaus Ole , Gottwald Karen , Rau David , Graf Christopher Günther Franz , Rozanski Elisabeth , Weidler Sascha , Unverzagt Carlo 
Published: September 2021

AbstractRecombinant human erythropoietin (EPO) is the main therapeutic glycoprotein for the treatment of anemia in cancer and kidney patients. The in‐vivo activity of EPO is carbohydrate‐dependent with the number of sialic acid residues regulating its circulatory half‐life. EPO carries threeN‐glycans and thus obtaining pure glycoforms provides a major challenge. We have developed a robust and reproducible chemoenzymatic approach to glycoforms of EPO with and without sialic acids. EPO was assembled by sequential native chemical ligation of two peptide and three glycopeptide segments. The glycopeptides were obtained by pseudoproline‐assisted Lansbury aspartylation. Enzymatic introduction of the sialic acids was readily accomplished at the level of the glycopeptide segments but even more efficiently on the refolded glycoprotein. Biological recognition of the synthetic EPOs was shown by formation of 1:1 complexes with recombinant EPO receptor.