Alloy design based on single-principal-element systems has approached its limit for performance enhancements. A substantial increase in strength up to gigapascal levels typically causes the premature ...failure of materials with reduced ductility. Here, we report a strategy to break this trade-off by controllably introducing high-density ductile multicomponent intermetallic nanoparticles (MCINPs) in complex alloy systems. Distinct from the intermetallic-induced embrittlement under conventional wisdom, such MCINP-strengthened alloys exhibit superior strengths of 1.5 gigapascals and ductility as high as 50% in tension at ambient temperature. The plastic instability, a major concern for high-strength materials, can be completely eliminated by generating a distinctive multistage work-hardening behavior, resulting from pronounced dislocation activities and deformation-induced microbands. This MCINP strategy offers a paradigm to develop next-generation materials for structural applications.
Nanometer-sized diamonds containing nitrogen-vacancy defect centers (NV) are promising nanosensors in biological environments due to their biocompatibility, bright fluorescence, and high magnetic ...sensitivity at ambient conditions. Here we report on the detection of ferritin molecules using magnetic noise induced by the inner paramagnetic iron as a contrast mechanism. We observe a significant reduction of both coherence and relaxation time due to the presence of ferritin on the surface of nanodiamonds. Our theoretical model is in excellent agreement with the experimental data and establishes this method as a novel sensing technology for proteins.
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IJS, KILJ, NUK, PNG, UL, UM
Nuclear magnetic resonance spectroscopy and magnetic resonance imaging at the ultimate sensitivity limit of single molecules or single nuclear spins requires fundamentally new detection strategies. ...The strong coupling regime, when interaction between sensor and sample spins dominates all other interactions, is one such strategy. In this regime, classically forbidden detection of completely unpolarized nuclei is allowed, going beyond statistical fluctuations in magnetization. Here we realize strong coupling between an atomic (nitrogen-vacancy) sensor and sample nuclei to perform nuclear magnetic resonance on four (29)Si spins. We exploit the field gradient created by the diamond atomic sensor, in concert with compressed sensing, to realize imaging protocols, enabling individual nuclei to be located with Angstrom precision. The achieved signal-to-noise ratio under ambient conditions allows single nuclear spin sensitivity to be achieved within seconds.
Precision sensing, and in particular high precision magnetometry, is a central goal of research into quantum technologies. For magnetometers, often trade-offs exist between sensitivity, spatial ...resolution, and frequency range. The precision, and thus the sensitivity of magnetometry, scales as 1/sqrtT_{2} with the phase coherence time T_{2} of the sensing system playing the role of a key determinant. Adapting a dynamical decoupling scheme that allows for extending T_{2} by orders of magnitude and merging it with a magnetic sensing protocol, we achieve a measurement sensitivity even for high frequency fields close to the standard quantum limit. Using a single atomic ion as a sensor, we experimentally attain a sensitivity of 4.6 pT/sqrtHz for an alternating-current magnetic field near 14 MHz. Based on the principle demonstrated here, this unprecedented sensitivity combined with spatial resolution in the nanometer range and tunability from direct current to the gigahertz range could be used for magnetic imaging in as of yet inaccessible parameter regimes.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Carbon cycling in the coastal zone affects global carbon budgets and is critical for understanding the urgent issues of hypoxia, acidification, and tidal wetland loss. However, there are no regional ...carbon budgets spanning the three main ecosystems in coastal waters: tidal wetlands, estuaries, and shelf waters. Here we construct such a budget for eastern North America using historical data, empirical models, remote sensing algorithms, and process‐based models. Considering the net fluxes of total carbon at the domain boundaries, 59 ± 12% (± 2 standard errors) of the carbon entering is from rivers and 41 ± 12% is from the atmosphere, while 80 ± 9% of the carbon leaving is exported to the open ocean and 20 ± 9% is buried. Net lateral carbon transfers between the three main ecosystem types are comparable to fluxes at the domain boundaries. Each ecosystem type contributes substantially to exchange with the atmosphere, with CO2 uptake split evenly between tidal wetlands and shelf waters, and estuarine CO2 outgassing offsetting half of the uptake. Similarly, burial is about equal in tidal wetlands and shelf waters, while estuaries play a smaller but still substantial role. The importance of tidal wetlands and estuaries in the overall budget is remarkable given that they, respectively, make up only 2.4 and 8.9% of the study domain area. This study shows that coastal carbon budgets should explicitly include tidal wetlands, estuaries, shelf waters, and the linkages between them; ignoring any of them may produce a biased picture of coastal carbon cycling.
Plain Language Summary
A carbon budget for a particular site or region describes the inputs and outputs of carbon to that site or region as well as the processes that change carbon from one form to another. A carbon budget is needed to fully understand many important issues facing coastal waters. We constructed the carbon budget for coastal waters of eastern North America. We found that about 60% of the carbon entering the domain is from rivers and about 40% is from the atmosphere, while about 80% of the carbon leaving the domain goes to the open ocean and about 20% is buried. Transfers of carbon from wetlands to estuaries and from estuaries to the ocean were as important as transfers of carbon at the domain boundaries. Tidal wetlands and estuaries were found to be important to the carbon budget despite making up only 2.4 and 8.9% of the study domain area, respectively. This study shows that coastal carbon budgets should explicitly consider tidal wetlands, estuaries, shelf waters, and the linkages between them; ignoring any of them may produce a biased picture of coastal carbon cycling.
Key Points
Tidal wetlands, estuaries, and shelf waters each contribute substantially to the carbon budget of eastern North American coastal waters
Study region net ecosystem production, atmospheric uptake, and burial are 20.2 ± 4.4, 5.1 ± 2.4, and 2.5 ± 0.7 Tg C yr−1, respectively
Net lateral carbon fluxes between tidal wetlands, estuaries, and shelf waters are large terms in the carbon budget of eastern North American coastal waters
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
We report the detection and polarization of nuclear spins in diamond at room temperature by using a single nitrogen-vacancy (NV) center. We use Hartmann-Hahn double resonance to coherently enhance ...the signal from a single nuclear spin while decoupling from the noisy spin bath, which otherwise limits the detection sensitivity. As a proof of principle, we (i) observe coherent oscillations between the NV center and a weakly coupled nuclear spin and (ii) demonstrate nuclear-bath cooling, which prolongs the coherence time of the NV sensor by more than a factor of 5. Our results provide a route to nanometer scale magnetic resonance imaging and novel quantum information processing protocols.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Isocitrate dehydrogenase (IDH) enzymes catalyse the oxidative decarboxylation of isocitrate and therefore play key roles in the Krebs cycle and cellular homoeostasis. Major advances in cancer ...genetics over the past decade have revealed that the genes encoding IDHs are frequently mutated in a variety of human malignancies, including gliomas, acute myeloid leukaemia, cholangiocarcinoma, chondrosarcoma and thyroid carcinoma. A series of seminal studies further elucidated the biological impact of the IDH mutation and uncovered the potential role of IDH mutants in oncogenesis. Notably, the neomorphic activity of the IDH mutants establishes distinctive patterns in cancer metabolism, epigenetic shift and therapy resistance. Novel molecular targeting approaches have been developed to improve the efficacy of therapeutics against IDH-mutated cancers. Here we provide an overview of the latest findings in IDH-mutated human malignancies, with a focus on glioma, discussing unique biological signatures and proceedings in translational research.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Distributions of surface water partial pressure of carbon dioxide (pCO2) were measured on nine cruises in the Delaware Estuary (USA). The Delaware River was highly supersaturated in pCO2 with respect ...to the atmosphere during all seasons, while the Delaware Bay was undersaturated in pCO2 during spring and late summer and moderately supersaturated during mid-summer, fall, and winter. While the smaller upper tidal river was a strong CO2 source (27.1 ± 6.4 mol-C m−2 yr−1), the much larger bay was a weak source (1.2 ± 1.4 mol-C m−2 yr−1), the latter of which had a much greater area than the former. In turn, the Delaware Estuary acted as a relatively weak CO2 source (2.4 ± 4.8 mol-C m−2 yr−1), which is in great contrast to many other estuarine systems. Seasonally, pCO2 changes were greatest at low salinities (0 ≤ S < 5), with pCO2 values in the summer nearly 3-fold greater than those observed in the spring and fall. Undersaturated pCO2 was observed over the widest salinity range (7.5 ≤ S < 30) during spring. Near to supersaturated pCO2 was generally observed in mid- to high-salinity waters (20 ≤ S < 30) except during spring and late summer. Strong seasonal trends in internal estuarine production and consumption of CO2 were observed throughout both the upper tidal river and lower bay. Positive correlations between river-borne and air–water CO2 fluxes in the upper estuary emphasize the significance of river-borne CO2 degassing to overall CO2 fluxes. While river-borne CO2 degassing heavily influenced CO2 dynamics in the upper tidal river, these forces were largely compensated for by internal biological processes within the extensive bay system of the lower estuary.
Abstract
Motivation
Single-cell RNA sequencing (scRNA-seq) technology has revolutionized the way research is done in biomedical sciences. It provides an unprecedented level of resolution across ...individual cells for studying cell heterogeneity and gene expression variability. Analyzing scRNA-seq data is challenging though, due to the sparsity and high dimensionality of the data.
Results
I developed scGEAToolbox—a Matlab toolbox for scRNA-seq data analysis. It contains a comprehensive set of functions for data normalization, feature selection, batch correction, imputation, cell clustering, trajectory/pseudotime analysis and network construction, which can be combined and integrated to building custom workflow. Although most of the functions are implemented in native Matlab, wrapper functions are provided to allow users to call the ‘third-party’ tools developed in Matlab or other languages. Furthermore, scGEAToolbox is equipped with sophisticated graphical user interfaces generated with App Designer, making it an easy-to-use application for quick data processing.
Availability and implementation
https://github.com/jamesjcai/scGEAToolbox.
Supplementary information
Supplementary data are available at Bioinformatics online.
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