bluuebunny/crossref_metadata_2025_split huggingface dataset:
Elucidating intrinsic contribution of d-orbital states to oxygen evolution electrocatalysis in oxides
Authors: Yun Tae Gyu , Heo Yoon , Bin Bae Hyung , Chung Sung-Yoon 
Published: February 2021

AbstractAlthough numerous studies on oxide catalysts for an efficient oxygen evolution reaction have been carried out to compare their catalytic performance and suggest new compositions, two significant constraints have been overlooked. One is the difference in electronic conduction behavior between catalysts (metallic versus insulating) and the other is the strong crystallographic surface orientation dependence of the catalysis in a crystal. Consequently, unless a comprehensive comparison of the oxygen-evolution catalytic activity between samples is made on a crystallographically identical surface with sufficient electron conduction, misleading interpretations on the catalytic performance and mechanism may be unavoidable. To overcome these limitations, we utilize both metallic (001) LaNiO3 epitaxial thin films together with metal dopants and semiconducting (001) LaCoO3 epitaxial thin films supported with a conductive interlayer. We identify that Fe, Cr, and Al are beneficial to enhance the catalysis in LaNiO3 although their perovskite counterparts, LaFeO3, LaCrO3, and LaAlO3, with a large bandgap are inactive. Furthermore, semiconducting LaCoO3 is found to have more than one order higher activity than metallic LaNiO3, in contrast to previous reports. Showing the importance of facilitating electron conduction, our work highlights the impact of the near-Fermi-level d-orbital states on the oxygen-evolution catalysis performance in perovskite oxides.
Structural elements in the flexible tail of the co-chaperone p23 coordinate client binding and progression of the Hsp90 chaperone cycle
Authors: Biebl Maximilian M. , Lopez Abraham , Rehn Alexandra , Freiburger Lee , Lawatscheck Jannis , Blank Birgit , Sattler Michael , Buchner Johannes 
Published: February 2021

AbstractThe co-chaperone p23 is a central part of the Hsp90 machinery. It stabilizes the closed conformation of Hsp90, inhibits its ATPase and is important for client maturation. Yet, how this is achieved has remained enigmatic. Here, we show that a tryptophan residue in the proximal region of the tail decelerates the ATPase by allosterically switching the conformation of the catalytic loop in Hsp90. We further show by NMR spectroscopy that the tail interacts with the Hsp90 client binding site via a conserved helix. This helical motif in the p23 tail also binds to the client protein glucocorticoid receptor (GR) in the free and Hsp90-bound form. In vivo experiments confirm the physiological importance of ATPase modulation and the role of the evolutionary conserved helical motif for GR activation in the cellular context.
Anomalous thickness dependence of Curie temperature in air-stable two-dimensional ferromagnetic 1T-CrTe2 grown by chemical vapor deposition
Authors: Meng Lingjia , Zhou Zhang , Xu Mingquan , Yang Shiqi , Si Kunpeng , Liu Lixuan , Wang Xingguo , Jiang Huaning , Li Bixuan , Qin Peixin , Zhang Peng , Wang Jinliang , Liu Zhiqi , Tang Peizhe , Ye Yu , Zhou Wu , Bao Lihong , Gao Hong-Jun , Gong Yongji 
Published: February 2021

AbstractThe discovery of ferromagnetic two-dimensional van der Waals materials has opened up opportunities to explore intriguing physics and to develop innovative spintronic devices. However, controllable synthesis of these 2D ferromagnets and enhancing their stability under ambient conditions remain challenging. Here, we report chemical vapor deposition growth of air-stable 2D metallic 1T-CrTe2 ultrathin crystals with controlled thickness. Their long-range ferromagnetic ordering is confirmed by a robust anomalous Hall effect, which has seldom been observed in other layered 2D materials grown by chemical vapor deposition. With reducing the thickness of 1T-CrTe2 from tens of nanometers to several nanometers, the easy axis changes from in-plane to out-of-plane. Monotonic increase of Curie temperature with the thickness decreasing from ~130.0 to ~7.6 nm is observed. Theoretical calculations indicate that the weakening of the Coulomb screening in the two-dimensional limit plays a crucial role in the change of magnetic properties.
Digital navigation of energy–structure–function maps for hydrogen-bonded porous molecular crystals
Authors: Zhao Chengxi , Chen Linjiang , Che Yu , Pang Zhongfu , Wu Xiaofeng , Lu Yunxiang , Liu Honglai , Day Graeme M. , Cooper Andrew I. 
Published: February 2021

AbstractEnergy–structure–function (ESF) maps can aid the targeted discovery of porous molecular crystals by predicting the stable crystalline arrangements along with their functions of interest. Here, we compute ESF maps for a series of rigid molecules that comprise either a triptycene or a spiro-biphenyl core, functionalized with six different hydrogen-bonding moieties. We show that the positioning of the hydrogen-bonding sites, as well as their number, has a profound influence on the shape of the resulting ESF maps, revealing promising structure–function spaces for future experiments. We also demonstrate a simple and general approach to representing and inspecting the high-dimensional data of an ESF map, enabling an efficient navigation of the ESF data to identify ‘landmark’ structures that are energetically favourable or functionally interesting. This is a step toward the automated analysis of ESF maps, an important goal for closed-loop, autonomous searches for molecular crystals with useful functions.
A flexible electromagnetic wave-electricity harvester
Authors: Lv Hualiang , Yang Zhihong , Liu Bo , Wu Guanglei , Lou Zhichao , Fei Ben , Wu Renbing 
Published: February 2021

AbstractDeveloping an ultimate electromagnetic (EM)-absorbing material that can not only dissipate EM energy but also convert the generated heat into electricity is highly desired but remains a significant challenge. Here, we report a hybrid Sn@C composite with a biological cell-like splitting ability to address this challenge. The composite consisting of Sn nanoparticles embedded within porous carbon would split under a cycled annealing treatment, leading to more dispersed nanoparticles with an ultrasmall size. Benefiting from an electron-transmitting but a phonon-blocking structure created by the splitting behavior, an EM wave-electricity device constructed by the optimum Sn@C composite could achieve an efficiency of EM to heat at widely used frequency region and a maximum thermoelectric figure of merit of 0.62 at 473 K, as well as a constant output voltage and power under the condition of microwave radiation. This work provides a promising solution for solving EM interference with self-powered EM devices.
Ultra-fast charging in aluminum-ion batteries: electric double layers on active anode
Authors: Shen Xuejing , Sun Tao , Yang Lei , Krasnoslobodtsev Alexey , Sabirianov Renat , Sealy Michael , Mei Wai-Ning , Wu Zhanjun , Tan Li 
Published: February 2021

AbstractWith the rapid iteration of portable electronics and electric vehicles, developing high-capacity batteries with ultra-fast charging capability has become a holy grail. Here we report rechargeable aluminum-ion batteries capable of reaching a high specific capacity of 200 mAh g−1. When liquid metal is further used to lower the energy barrier from the anode, fastest charging rate of 104 C (duration of 0.35 s to reach a full capacity) and 500% more specific capacity under high-rate conditions are achieved. Phase boundaries from the active anode are believed to encourage a high-flux charge transfer through the electric double layers. As a result, cationic layers inside the electric double layers responded with a swift change in molecular conformation, but anionic layers adopted a polymer-like configuration to facilitate the change in composition.
Anoxic chlorophyll maximum enhances local organic matter remineralization and nitrogen loss in Lake Tanganyika
Authors: Callbeck Cameron M. , Ehrenfels Benedikt , Baumann Kathrin B. L. , Wehrli Bernhard , Schubert Carsten J. 
Published: February 2021

AbstractIn marine and freshwater oxygen-deficient zones, the remineralization of sinking organic matter from the photic zone is central to driving nitrogen loss. Deep blooms of photosynthetic bacteria, which form the suboxic/anoxic chlorophyll maximum (ACM), widespread in aquatic ecosystems, may also contribute to the local input of organic matter. Yet, the influence of the ACM on nitrogen and carbon cycling remains poorly understood. Using a suite of stable isotope tracer experiments, we examined the transformation of nitrogen and carbon under an ACM (comprising of Chlorobiaceae and Synechococcales) and a non-ACM scenario in the anoxic zone of Lake Tanganyika. We find that the ACM hosts a tight coupling of photo/litho-autotrophic and heterotrophic processes. In particular, the ACM was a hotspot of organic matter remineralization that controlled an important supply of ammonium driving a nitrification-anammox coupling, and thereby played a key role in regulating nitrogen loss in the oxygen-deficient zone.
The effects of releasing early results from ongoing clinical trials
Authors: Ventz Steffen , Bacallado Sergio , Rahman Rifaquat , Tolaney Sara , Schoenfeld Jonathan D. , Alexander Brian M. , Trippa Lorenzo 
Published: February 2021

AbstractMost trials do not release interim summaries on efficacy and toxicity of the experimental treatments being tested, with this information only released to the public after the trial has ended. While early release of clinical trial data to physicians and patients can inform enrollment decision making, it may also affect key operating characteristics of the trial, statistical validity and trial duration. We investigate the public release of early efficacy and toxicity results, during ongoing clinical studies, to better inform patients about their enrollment options. We use simulation models of phase II glioblastoma (GBM) clinical trials in which early efficacy and toxicity estimates are periodically released accordingly to a pre-specified protocol. Patients can use the reported interim efficacy and toxicity information, with the support of physicians, to decide which trial to enroll in. We describe potential effects on various operating characteristics, including the study duration, selection bias and power.
Rapid electrochemical detection of coronavirus SARS-CoV-2
Authors: Chaibun Thanyarat , Puenpa Jiratchaya , Ngamdee Tatchanun , Boonapatcharoen Nimaradee , Athamanolap Pornpat , O’Mullane Anthony Peter , Vongpunsawad Sompong , Poovorawan Yong , Lee Su Yin , Lertanantawong Benchaporn 
Published: February 2021

AbstractCoronavirus disease 2019 (COVID-19) is a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Diagnosis of COVID-19 depends on quantitative reverse transcription PCR (qRT-PCR), which is time-consuming and requires expensive instrumentation. Here, we report an ultrasensitive electrochemical biosensor based on isothermal rolling circle amplification (RCA) for rapid detection of SARS-CoV-2. The assay involves the hybridization of the RCA amplicons with probes that were functionalized with redox active labels that are detectable by an electrochemical biosensor. The one-step sandwich hybridization assay could detect as low as 1 copy/μL of N and S genes, in less than 2 h. Sensor evaluation with 106 clinical samples, including 41 SARS-CoV-2 positive and 9 samples positive for other respiratory viruses, gave a 100% concordance result with qRT-PCR, with complete correlation between the biosensor current signals and quantitation cycle (Cq) values. In summary, this biosensor could be used as an on-site, real-time diagnostic test for COVID-19.
Pathological conformations of disease mutant Ryanodine Receptors revealed by cryo-EM
Authors: Woll Kellie A. , Haji-Ghassemi Omid , Van Petegem Filip 
Published: February 2021

AbstractRyanodine Receptors (RyRs) are massive channels that release Ca2+ from the endoplasmic and sarcoplasmic reticulum. Hundreds of mutations are linked to malignant hyperthermia (MH), myopathies, and arrhythmias. Here, we explore the first MH mutation identified in humans by providing cryo-EM snapshots of the pig homolog, R615C, showing that it affects an interface between three solenoid regions. We also show the impact of apo-calmodulin (apoCaM) and how it can induce opening by bending of the bridging solenoid, mediated by its N-terminal lobe. For R615C RyR1, apoCaM binding abolishes a pathological ‘intermediate’ conformation, distributing the population to a mixture of open and closed channels, both different from the structure without apoCaM. Comparisons show that the mutation primarily affects the closed state, inducing partial movements linked to channel activation. This shows that disease mutations can cause distinct pathological conformations of the RyR and facilitate channel opening by disrupting interactions between different solenoid regions.
Lung microbiota associations with clinical features of COPD in the SPIROMICS cohort
Authors: Opron Kristopher , Begley Lesa A. , Erb-Downward John R. , Freeman Christine , Madapoosi Siddharth , Alexis Neil E. , Barjaktarevic Igor , Graham Barr R. , Bleecker Eugene R. , Bowler Russell P. , Christenson Stephanie A. , Comellas Alejandro P. , Cooper Christopher B. , Couper David J. , Doerschuk Claire M. , Dransfield Mark T. , Han MeiLan K. , Hansel Nadia N. , Hastie Annette T. , Hoffman Eric A. , Kaner Robert J. , Krishnan Jerry , O’Neal Wanda K. , Ortega Victor E. , Paine Robert , Peters Stephen P. , Michael Wells J. , Woodruff Prescott G. , Martinez Fernando J. , Curtis Jeffrey L. , Huffnagle Gary B. , Huang Yvonne J. 
Published: February 2021

AbstractChronic obstructive pulmonary disease (COPD) is heterogeneous in development, progression, and phenotypes. Little is known about the lung microbiome, sampled by bronchoscopy, in milder COPD and its relationships to clinical features that reflect disease heterogeneity (lung function, symptom burden, and functional impairment). Using bronchoalveolar lavage fluid collected from 181 never-smokers and ever-smokers with or without COPD (GOLD 0-2) enrolled in the SubPopulations and InteRmediate Outcome Measures In COPD Study (SPIROMICS), we find that lung bacterial composition associates with several clinical features, in particular bronchodilator responsiveness, peak expiratory flow rate, and forced expiratory flow rate between 25 and 75% of FVC (FEF25–75). Measures of symptom burden (COPD Assessment Test) and functional impairment (six-minute walk distance) also associate with disparate lung microbiota composition. Drivers of these relationships include members of theStreptococcus, Prevotella, Veillonella, Staphylococcus, andPseudomonasgenera. Thus, lung microbiota differences may contribute to airway dysfunction and airway disease in milder COPD.
Biogeographical patterns and mechanisms of microbial community assembly that underlie successional biocrusts across northern China
Authors: Li Yuanlong , Hu Chunxiang 
Published: February 2021

AbstractBiocrusts play critical eco-functions in many drylands, however it is challenging to explore their community assembly, particularly within patched successional types and across climate zones. Here, different successional biocrusts (alga, lichen, and moss-dominated biocrusts) were collected across the northern China, and assembly of biocrust microbial communities was investigated by high-throughput sequencing combined with measurements of soil properties and microclimate environments. Bacterial and eukaryotic communities showed that the maximum and minimum community variation occurred across longitude and latitude, respectively. In the regions where all three stages of biocrusts were involved, the highest community difference existed between successional stages, and decreased with distance. The community assembly was generally driven by dispersal limitation, although neutral processes have controlled the eukaryotic community assembly in hyperarid areas. Along the succession, bacterial community had no obvious patterns, but eukaryotic community showed increasing homogeneity, with increased species sorting and decreased dispersal limitation for community assembly. Compared to early successional biocrusts, there were higher microbial mutual exclusions and more complex networks at later stages, with distinct topological features. Correlation analysis further indicated that the balance between deterministic and stochastic processes might be mediated by aridity, salinity, and total phosphorus, although the mediations were opposite for bacteria and eukaryotes.
Topological representations of crystalline compounds for the machine-learning prediction of materials properties
Authors: Jiang Yi , Chen Dong , Chen Xin , Li Tangyi , Wei Guo-Wei , Pan Feng 
Published: February 2021

AbstractAccurate theoretical predictions of desired properties of materials play an important role in materials research and development. Machine learning (ML) can accelerate the materials design by building a model from input data. For complex datasets, such as those of crystalline compounds, a vital issue is how to construct low-dimensional representations for input crystal structures with chemical insights. In this work, we introduce an algebraic topology-based method, called atom-specific persistent homology (ASPH), as a unique representation of crystal structures. The ASPH can capture both pairwise and many-body interactions and reveal the topology-property relationship of a group of atoms at various scales. Combined with composition-based attributes, ASPH-based ML model provides a highly accurate prediction of the formation energy calculated by density functional theory (DFT). After training with more than 30,000 different structure types and compositions, our model achieves a mean absolute error of 61 meV/atom in cross-validation, which outperforms previous work such as Voronoi tessellations and Coulomb matrix method using the same ML algorithm and datasets. Our results indicate that the proposed topology-based method provides a powerful computational tool for predicting materials properties compared to previous works.
Efficient and noise resilient measurements for quantum chemistry on near-term quantum computers
Authors: Huggins William J. , McClean Jarrod R. , Rubin Nicholas C. , Jiang Zhang , Wiebe Nathan , Whaley K. Birgitta , Babbush Ryan 
Published: February 2021

AbstractVariational algorithms are a promising paradigm for utilizing near-term quantum devices for modeling electronic states of molecular systems. However, previous bounds on the measurement time required have suggested that the application of these techniques to larger molecules might be infeasible. We present a measurement strategy based on a low-rank factorization of the two-electron integral tensor. Our approach provides a cubic reduction in term groupings over prior state-of-the-art and enables measurement times three orders of magnitude smaller than those suggested by commonly referenced bounds for the largest systems we consider. Although our technique requires execution of a linear-depth circuit prior to measurement, this is compensated for by eliminating challenges associated with sampling nonlocal Jordan–Wigner transformed operators in the presence of measurement error, while enabling a powerful form of error mitigation based on efficient postselection. We numerically characterize these benefits with noisy quantum circuit simulations for ground-state energies of strongly correlated electronic systems.
Tight finite-key security for twin-field quantum key distribution
Authors: Currás-Lorenzo Guillermo , Navarrete Álvaro , Azuma Koji , Kato Go , Curty Marcos , Razavi Mohsen 
Published: February 2021

AbstractQuantum key distribution (QKD) offers a reliable solution to communication problems that require long-term data security. For its widespread use, however, the rate and reach of QKD systems must be improved. Twin-field (TF) QKD is a step forward toward this direction, with early demonstrations suggesting it can beat the current rate-versus-distance records. A recently introduced variant of TF-QKD is particularly suited for experimental implementation, and has been shown to offer a higher key rate than other variants in the asymptotic regime, where users exchange an infinite number of signals. Here, we extend the security of this protocol to the finite-key regime, showing that it can overcome the fundamental bounds on point-to-point QKD with ~1010 transmitted signals. In many practical regimes of interest, our analysis offers higher key rates than those of alternative variants. Moreover, some of the techniques we develop are applicable to the finite-key analysis of other QKD protocols.
Creation of Greenberger-Horne-Zeilinger states with thousands of atoms by entanglement amplification
Authors: Zhao Yajuan , Zhang Rui , Chen Wenlan , Wang Xiang-Bin , Hu Jiazhong 
Published: February 2021

AbstractWe propose an entanglement-creation scheme in a multi-atom ensemble trapped in an optical cavity, named entanglement amplification, converting unentangled states into entangled states and amplifying less-entangled ones to maximally entangled Greenberger-Horne-Zeilinger (GHZ) states whose fidelity is logarithmically dependent on the atom number and robust against common experimental noises. The scheme starts with a multi-atom ensemble initialized in a coherent spin state. By shifting the energy of a particular Dicke state, we break the Hilbert space of the ensemble into two isolated subspaces to tear the coherent spin state into two components so that entanglement is introduced. After that, we utilize the isolated subspaces to further enhance the entanglement by coherently separating the two components. By single-particle Rabi drivings on atoms in a high-finesse optical cavity illuminated by a single-frequency light, 2000-atom GHZ states can be created with a fidelity above 80% in an experimentally achievable system, making resources of ensembles at Heisenberg limit practically available for quantum metrology.
Extracellular DNA, cell surface proteins and c-di-GMP promote biofilm formation in Clostridioides difficile
Authors: Dawson Lisa F. , Peltier Johann , Hall Catherine L. , Harrison Mark A. , Derakhshan Maria , Shaw Helen A. , Fairweather Neil F. , Wren Brendan W. 
Published: February 2021

AbstractClostridioides difficile is the leading cause of nosocomial antibiotic-associated diarrhoea worldwide, yet there is little insight into intestinal tract colonisation and relapse. In many bacterial species, the secondary messenger cyclic-di-GMP mediates switching between planktonic phase, sessile growth and biofilm formation. We demonstrate that c-di-GMP promotes early biofilm formation in C. difficile and that four cell surface proteins contribute to biofilm formation, including two c-di-GMP regulated; CD2831 and CD3246, and two c-di-GMP-independent; CD3392 and CD0183. We demonstrate that C. difficile biofilms are composed of extracellular DNA (eDNA), cell surface and intracellular proteins, which form a protective matrix around C. difficile vegetative cells and spores, as shown by a protective effect against the antibiotic vancomycin. We demonstrate a positive correlation between biofilm biomass, sporulation frequency and eDNA abundance in all five C. difficile lineages. Strains 630 (RT012), CD305 (RT023) and M120 (RT078) contain significantly more eDNA in their biofilm matrix than strains R20291 (RT027) and M68 (RT017). DNase has a profound effect on biofilm integrity, resulting in complete disassembly of the biofilm matrix, inhibition of biofilm formation and reduced spore germination. The addition of exogenous DNase could be exploited in treatment of C. difficile infection and relapse, to improve antibiotic efficacy.