The Adoption of Blockchain Technologies in Data Sharing: A State of the Art Survey

In the big data era, it is a significant need for data sharing in various industries. However, there are many weaknesses in the traditional centralized way of data sharing. It is easy to attack the centralized data storage center. As the process of data asset transactions is not transparent, there is a lack of trust in the percipients of data sharing. Blockchain technology offers a possibility to solve these problems in data sharing, as the blockchain can provide a decentralized, programmable, tamperproof, and anonymous data sharing environment. In this paper, we compare the blockchain-based data sharing with the traditional ways of data sharing, and analyze the scenarios in major industry applications. We survey the state of the art of the adoption of blockchain technologies in data sharing, and provide a summary about their technical frameworks and schemes

Measuring design compliance using neural language models: An automotive case study

As the modern vehicle becomes more software-defined, it is beginning to take significant effort to avoid serious regression in software design. This is because automotive software architects rely largely upon manual review of code to spot deviations from specified design principles. Such an approach is both inefficient and prone to error. In recent days, neural language models pre-trained on source code are beginning to be used for automating a variety of programming tasks. In this work, we extend the application of such a Programming Language Model (PLM) to automate the assessment of design compliance. Using a PLM, we construct a system that assesses whether a set of query programs comply with Controller-Handler, a design pattern specified to ensure hardware abstraction in automotive control software. The assessment is based upon measuring whether the geometrical arrangement of query program embeddings, extracted from the PLM, aligns with that of a set of known implementations of the pattern. The level of alignment is then transformed into an interpretable measure of compliance. Using a controlled experiment, we demonstrate that our technique determines compliance with a precision of 92%. Also, using expert review to calibrate the automated assessment, we introduce a protocol to determine the nature of the violation, helping eventual refactoring. Results from this work indicate that neural language models can provide valuable assistance to human architects in assessing and fixing violations in automotive software design

Three-dimensional array of microbubbles sonoporation of cells in microfluidics

Sonoporation is a popular membrane disruption technique widely applicable in various fields, including cell therapy, drug delivery, and biomanufacturing. In recent years, there has been significant progress in achieving controlled, high-viability, and high-efficiency cell sonoporation in microfluidics. If the microchannels are too small, especially when scaled down to the cellular level, it still remains a challenge to overcome microchannel clogging, and low throughput. Here, we presented a microfluidic device capable of modulating membrane permeability through oscillating three-dimensional array of microbubbles. Simulations were performed to analyze the effective range of action of the oscillating microbubbles to obtain the optimal microchannel size. Utilizing a high-precision light curing 3D printer to fabricate uniformly sized microstructures in a one-step on both the side walls and the top surface for the generation of microbubbles. These microbubbles oscillated with nearly identical amplitudes and frequencies, ensuring efficient and stable sonoporation within the system. Cells were captured and trapped on the bubble surface by the acoustic streaming and secondary acoustic radiation forces induced by the oscillating microbubbles. At a driving voltage of 30 Vpp, the sonoporation efficiency of cells reached 93.9% ± 2.4%

Preoperative Aspirin Use and Its Effect on Adverse Events in Patients Undergoing Cardiac Operations

BackgroundPreoperative aspirin use within 5 days of cardiac operations is controversial. Aspirin could reduce cardiovascular complications and yet might increase risk of bleeding. Recent reports showed conflicting results, and whether aspirin has variable effects for different cardiac surgical procedures is unclear.MethodsA single-center retrospective cohort analysis was performed. After propensity score matching (PSM) for identified confounders, the relationship between preoperative aspirin use and 30-day all-cause mortality, postoperative renal failure, major adverse cardiocerebral events (MACE), blood transfusion, reoperation for bleeding, and postoperative infection were estimated with separate logistic regression models.ResultsPreoperative aspirin therapy was associated with a 49% (p = 0.04) increased risk of reoperation for bleeding among 868 matched pairs of patients undergoing valve operations. Among 725 matched patients undergoing coronary artery bypass grafting (CABG), preoperative aspirin therapy was not associated with a statistically significant higher risk of reoperation for bleeding. However, preoperative aspirin use, compared with nonuse, was not associated with risks of MACE, 30-day mortality, postoperative renal failure, blood transfusion, or postoperative infection in the entire cohort, in patients undergoing valve operations only, and in patients undergoing CABG only after PSM.ConclusionsPreoperative aspirin use in all patients undergoing cardiac operations was not associated with risks of major cardiac, cerebral, or renal complications and infections and death; however, the risk of reoperation for bleeding was elevated among preoperative aspirin users compared with nonusers in a subpopulation of patients undergoing valve operations only

Size Effect and Deformation Mechanism in Twinned Copper Nanowires

Molecular dynamics simulations were performed to demonstrate the synergistic effects of the extrinsic size (nanowire length) and intrinsic size (twin boundary spacing) on the failure manner, yield strength, ductility and deformation mechanism of the twinned nanowires containing high density coherent twin boundaries CTBs paralleled to the nanowires’ axis. The twinned nanowires show an intense extrinsic size effect, i.e., shorter is stronger and more ductile, and an intense intrinsic size effect, i.e., thinner is stronger. Notably, the strengthening effect degradation of CTBs in the twinned nanowires is observed with an increase in nanowire length: remarkable strengthening effect can be obtained for the short nanowires, but the strengthening effect becomes less pronounced for the long nanowires. The twinned nanowires fail via a ductile manner or via a brittle manner depending on the synergistic effect of the nanowire length and twin boundary spacing. By atomic-level observation of the plastic deformation, we found that the emission of a trailing 30° partial from the free surface controls the yield behavior of the twinned nanowires. We also found that the special zigzag extended dislocations are formed by the dislocation–CTBs interactions, and propagate to sustain the plastic deformation

Rebuilding the Strain Hardening at a Large Strain in Twinned Au Nanowires

Metallic nanowires usually exhibit ultrahigh strength but low tensile ductility, owing to their limited strain hardening capability. Here, our larger scale molecular dynamics simulations demonstrated that we could rebuild the highly desirable strain hardening behavior at a large strain (0.21 to 0.31) in twinned Au nanowires by changing twin orientation, which strongly contrasts with the strain hardening at the incipient plastic deformation in low stacking-fault energy metals nanowires. Because of this strain hardening, an improved ductility is achieved. With the change of twin orientation, a competing effect between partial dislocation propagation and twin migration is observed in nanowires with slant twin boundaries. When twin migration gains the upper hand, the strain hardening occurs. Otherwise, the strain softening occurs. As the twin orientation increases from 0° to 90°, the dominating deformation mechanism shifts from slip-twin boundary interaction to dislocation slip, twin migration, and slip transmission in sequence. Our work could not only deepen our understanding of the mechanical behavior and deformation mechanism of twinned Au nanowires, but also provide new insights into enhancing the strength and ductility of nanowires by engineering the nanoscale twins

Improved Corrosion Resistance of Magnesium Alloy in Simulated Concrete Pore Solution by Hydrothermal Treatment

Magnesium alloys are considered for building materials in this study due to their natural immunity to corrosion in alkaline concrete pore solution. But, chloride ions attack often hinders the application of most metals. Therefore, it is necessary to conduct a preliminary corrosion evaluation and attempt to find an effective way to resist the attack of chloride ions in concrete pore solution. In our study, hydrothermal treatment is carried out to modify Mg-9.3 wt. % Al alloy. After the treatment in NaOH solution for 10 h, scanning electron microscopy (SEM) reveals that a layer of dense coating with a thickness of about 5 μm is formed on Mg alloy. Energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and X-ray Diffraction (XRD) are combined to analyze the coating, and it is thereby confirmed that the coating is mainly composed of Mg(OH)2. As expected, both immersion test and electrochemical corrosion test show that the coated magnesium alloy has a better corrosion resistance than the uncoated one in simulated concrete pore solution with and without chloride ions. In summary, it indicates that hydrothermal treatment is a feasible method to improve the corrosion resistance of Mg alloys used for building engineering from the perspective of corrosion science

Corrosion Behavior in Hydrochloric Acid of Pure Titanium after Ultrasonic Severe Surface Rolling

Designing a gradient nanostructure is regarded as an effective strategy for strengthening commercial pure Ti without seriously sacrificing ductility. However, the corrosion behavior of the gradient nanostructured (GNS) pure Ti is far from clear, especially in reducing acid in which pure Ti shows poor corrosion resistance. The present paper aims at investigating the corrosion behavior of GNS pure Ti in hydrochloric acid by electrochemical method. The GNS surface layer is produced by a recently developed method called ultrasonic severe surface rolling. The GNS pure Ti exhibits spontaneous passivation behavior as well as the coarse-grained one in 1 M HCl. Due to the GNS surface layer, the corrosion current density and passive current density decrease by 70% and 54%, respectively, giving rise to significantly enhanced corrosion resistance and passivation ability. The better corrosion resistance is believed to be ascribed to the high-density grain boundaries and dislocations induced by the surface nano-grained structure as well as the smooth surface with few surface defects. The USSR processing also enlarges the static water contact angle of the pure Ti to 61.0 ± 0.3°