Reconstruction of sparsely sampled seismic data is critical for maintaining the quality of seismic images when significant numbers of shots and receivers are missing. We present a reconstruction ...method in the shot-receiver-time (SRT) domain based on a residual U-Net machine learning architecture, for seismic data acquired in a sparse 2-D acquisition and name it SRT2D-ResU-Net. The SRT domain retains a high level of seismic signal connectivity, which is likely the main data feature that the reconstructing algorithms rely on. We develop an " in situ training and prediction" workflow by dividing the acquisition area into two nonoverlapping subareas: a training subarea for establishing the network model using regularly sampled data and a testing subarea for reconstructing the sparsely sampled data using the trained model. To establish a reference base for analyzing the changes in data features over the study area, and quantifying the reconstructed seismic data, we devise a baseline reference using a tiny portion of the field data. The baselines are properly spaced and excluded from the training and reconstruction processes. The results on a field marine data set show that the SRT2D-ResU-Net can effectively learn the features of seismic data in the training process, and the average correlation between the reconstructed missing traces and the true answers is over 85%.
A robust, superamphiphobic fabric with a novel self‐healing ability to autorepair from chemical damage is prepared by a two‐step wet‐chemistry coating technique using an easily available material ...system consisting of poly(vinylidene fluoride‐co‐hexafluoropropylene), fluoroalkyl silane, and modified silica nanoparticles. The coated fabrics can withstand at least 600 cycles of standard laundry and 8000 cycles of abrasion without apparently changing the superamphiphobicity. The coating is also very stable to strong acid/base, ozone, and boiling treatments. After being damaged chemically, the coating can restore its super liquid‐repellent properties by a short‐time heating treatment or room temperature ageing. This simple but novel and effective coating system may be useful for the development of robust protective clothing for various applications.
A superamphiphobic fabric with self‐healing ability to autorepair against chemical damage is prepared with a two‐step wet‐chemistry coating technique using a readily available material system. The coating withstands repeated washing and severe abrasion, as well as strong acid/base, ozone, and boiling treatments.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
With the increasing number of individuals with diabetes and obesity, nonalcoholic fatty liver disease (NAFLD) is becoming increasingly prevalent, affecting one-quarter of adults worldwide. The ...spectrum of NAFLD ranges from simple steatosis or nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH). NAFLD, especially NASH, may progress to fibrosis, leading to cirrhosis and hepatocellular carcinoma. NAFLD can impose a severe economic burden, and patients with NAFLD-related terminal or deteriorative liver diseases have become one of the main groups receiving liver transplantation. The increasing prevalence of NAFLD and the severe outcomes of NASH make it necessary to use effective methods to identify NAFLD. Although recognized as the gold standard, biopsy is limited by its sampling bias, poor acceptability, and severe complications, such as mortality, bleeding, and pain. Therefore, noninvasive methods are urgently needed to avoid biopsy for diagnosing NAFLD. This review discusses the current noninvasive methods for assessing NAFLD, including steatosis, NASH, and NAFLD-related fibrosis, and explores the advantages and disadvantages of measurement tools. In addition, we analyze potential noninvasive biomarkers for tracking disease processes and monitoring treatment effects, and explore effective algorithms consisting of imaging and nonimaging biomarkers for diagnosing advanced fibrosis and reducing unnecessary biopsies in clinical practice.
Graphene nanosheets (GNS) are the promising nano-reinforcements to fabricate bulk graphene-metal composites due to their excellent mechanical properties and large yield. However, the effective ...synthesis of such bulk graphene reinforced magnesium (Mg) composites remains challenging because of the poor interfacial bonding and the aggregation of GNS. Here, GNS possessing about 12 at. % residual oxygen (∼7:1 C/O ratio) was synthesized by a thermal reduction method. These residual oxygen in GNS is beneficial to increase the interfacial bonding between GNS and the matrix of α-Mg by MgO nanoparticles, which synthesized through the occurrence of a reaction between the residual oxygen and α-Mg in the composites. TEM analysis reveals that the in-situ synthesized MgO nanoparticles can significantly improve the interfacial bonding between GNS and α-Mg owing to the formation of semi-coherent interface of MgO/α-Mg and the distortion area bonding interface of GNS/MgO. By filling 0.5 wt. % of GNS, the yield strength and elongation of the composite increased by 76.2% and 24.3%, respectively as compared to the matrix alloy. The significant improvement in mechanical properties of the composites is mainly due to the grain refinement, strong interfacial bonding and dislocation strengthening.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Existing coating systems for preparing superamphiphobic surfaces are predominantly confined to small‐scale uses due to the heavy use of organic solvents. Waterborne coating treatment is highly ...desirable for the high safety, low cost, and nonenvironmental impact, but it remains difficult to develop due to the problems in forming durable, homogeneous coating from an aqueous dispersion of amphiphobic substances. In this study, the authors have proved that lyophobic nanoparticles, fluorinated alkyl silane (FAS), and fluorocarbon surfactant can form a stable dispersion in water, suitable for preparing durable superamphiphobic surfaces on various solid substrates. A series of substrates including fabrics, sponge, wood, glass, and metal, after being coated with this ternary coating system, shows superamphiphobicity with low contact angle hysteresis. The coating is durable enough against physical abrasion, repeated washing, boiling in water, and strong acid/base attacks. Benefiting from FAS, the coating also has a self‐healing ability against both physical and chemical damages. The unexpected stability of the ternary dispersion is a result of the synergistic interaction of the three ingredients. Results from this study may promote the wide development of safe and cost‐efficient superamphiphobic techniques for diverse applications.
A waterborne coating system consisting of lyophobic nanoparticles, fluorinated alkyl silane, and fluorocarbon surfactant is developed to make various substrates having a superamphiphobic surface with low contact angle hysteresis. The coating is durable against physical abrasion, repeated washing, boiling in water, and strong acid/base attacks. It also has a self‐healing ability against both physical and chemical damages.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The oscillatory bubble pulses generated by airguns in seawater are known to produce artefacts in seismic images. Although such artefacts are suppressible by employing larger airgun arrays in ...acquisition, small airgun arrays are used more often now to minimize the environmental impacts, thus raising the need for further suppressing bubble pulses at data processing stage. For a deep marine reflection dataset recently acquired by a small airgun array, we compare the effectiveness of three popular debubbling methods that estimate the far‐field source signature based on theoretical simulation and wavelets extracted from seafloor reflections and direct arrivals, respectively. In this case, due to the lack of near‐field measurements for calibration, the debubbling via simulation underperforms the two wavelet extraction methods. Overlapping events in the noisy response of seafloor sediments lead to the failure of the wavelet extraction from primary seafloor reflections. The estimated source signature based on direct arrivals achieves the best bubble suppression result, indicating the importance of signal‐to‐noise ratio and a low level of directionality of the small airgun array source.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The absorption and photoluminescence, both steady‐state and time‐resolved, of CsPbX3 (X = Cl, Br, I) nanocrystals are reported at temperatures ranging from 3 to 300 K. These measurements offer a ...unique window into the fundamental properties of this class of materials which is considered promising for light‐emitting and detection devices. The bandgaps are shown to increase from low to high temperature, and none of the examined cesium‐based perovskite nanocrystals exhibit a bandgap discontinuity in this temperature range suggesting constant crystal phase. Time‐resolved measurements show that the radiative lifetime of the band‐edge emission depends strongly on the halide ion and increases with heating. The increasing lifetime at higher temperatures is attributed primarily to free carriers produced from exciton fission, corroborated by the prevalence of excitonic character in absorption. The results particularly highlight many of the similarities in physical properties, such as low exciton binding energy and long lifetime, between CsPbI3 and hybrid organic–inorganic plumbotrihalide perovskites.
Temperature‐dependent optical studies of CsPbX3 (X = Cl, Br, I) nanocrystals in the bulk‐like size regime demonstrate the bright nature of the lowest emitting state of this class of materials. Low‐temperature absorption measurements directly reveal the composition‐dependent exciton binding energy. Dynamic measurements strongly suggest increased lifetimes at higher temperatures are due to exciton fission.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Mediation analysis is a useful tool in randomized trials for understanding how a treatment works, in particular how much of the treatment's effect on an outcome is explained by a mediator variable. ...The traditional approach to mediation analysis makes sequential ignorability assumption which precludes the existence of unobserved confounders between the mediator and outcome variables. Since the randomized experiment does not randomize the mediator, sequential ignorability may not be plausible. In this article, based on a statistical model termed sure outcomes of random events model, we propose an alternative approach to causal mediation analysis without relying on the sequential ignorability assumption for the case of binary treatment and mediator variables. When the outcome is also binary, we establish the identifiability of the average natural direct and indirect effects in the presence of an unobserved confounder between mediator and outcome variables. More importantly, if the identifiability conditions are violated, we provide new bounds that are narrower than those in the previous studies, and these bound results are extended to the case of an arbitrary bounded outcome. Simulation studies show good performance for the proposed estimators in finite samples. Finally, we use a job training intervention on the mental health study to illustrate our approach.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Significance Alzheimer’s disease (AD) is a devastating disease that results in the progressive cognitive deficits of elderly and has become one of major social and economic burdens worldwide. There ...is no effective drug or therapy to prevent or halt the progressive cognitive dysfunctions due to the complex mechanisms such as accumulation of amyloid-β (Aβ), increase in oxidative stress, and formation of neurofibrillary tangle that drive the development of the disease. We found here that Edaravone, a drug that has been used for ischemic stroke, is able to prevent and treat AD by targeting multiple pathways of AD pathogenesis and rescuing the cognitive deficits of a mouse model of AD. Our study suggests Edaravone is a promising drug candidate for AD.
Alzheimer’s disease (AD) is one of most devastating diseases affecting elderly people. Amyloid-β (Aβ) accumulation and the downstream pathological events such as oxidative stress play critical roles in pathogenesis of AD. Lessons from failures of current clinical trials suggest that targeting multiple key pathways of the AD pathogenesis is necessary to halt the disease progression. Here we show that Edaravone, a free radical scavenger that is marketed for acute ischemic stroke, has a potent capacity of inhibiting Aβ aggregation and attenuating Aβ-induced oxidation in vitro. When given before or after the onset of Aβ deposition via i.p. injection, Edaravone substantially reduces Aβ deposition, alleviates oxidative stress, attenuates the downstream pathologies including Tau hyperphosphorylation, glial activation, neuroinflammation, neuronal loss, synaptic dysfunction, and rescues the behavioral deficits of APPswe/PS1 mice. Oral administration of Edaravone also ameliorates the AD-like pathologies and memory deficits of the mice. These findings suggest that Edaravone holds a promise as a therapeutic agent for AD by targeting multiple key pathways of the disease pathogenesis.
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