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Molecular computing is an emerging paradigm that plays an essential role in data storage, bio-computation, and clinical diagnosis with the future trends of more efficient computing scheme, higher modularity with scaled-up circuity and stronger tolerance of corrupted inputs in a complex environment. Towards these goals, we construct a spatially localized, DNA integrated circuits-based classifier (DNA IC-CLA) that can perform neuromorphic architecture-based computation at a molecular level for medical diagnosis. The DNA-based classifier employs a two-dimensional DNA origami as the framework and localized processing modules as the in-frame computing core to execute arithmetic operations (e.g. multiplication, addition, subtraction) for efficient linear classification of complex patterns of miRNA inputs. We demonstrate that the DNA IC-CLA enables accurate cancer diagnosis in a faster (about 3 h) and more effective manner in synthetic and clinical samples compared to those of the traditional freely diffusible DNA circuits. We believe that this all-in-one DNA-based classifier can exhibit more applications in biocomputing in cells and medical diagnostics. Molecular computing is an emerging paradigm with a crucial role in clinical diagnosis. Here, authors develop a spatially localized, DNA-integrated circuits-based classifier, DNA IC-CLA, which enables accurate cancer diagnosis for clinical samples in a faster and more effective manner. [ABSTRACT FROM AUTHOR]

The remarkable effect of a double primary support has been proven in squeezing soft rock tunnels, but the research on the excavation and support time is still insufficient. In this study, the causes and failure mechanism of the large deformation in the Dongmachang I tunnel were investigated from the geostress field and the surrounding rock conditions. The supporting mechanism of the single and double primary supports in a tunnel and the deformation laws of different bench excavation lengths and support times were analyzed. Based on the Burgers model, creep materials similar to the argillaceous siltstone and materials similar to the concrete and steel arch of the double primary support were designed. The effects of the different bench lengths and the second primary support time on tunnel stability were evaluated by model tests. It was shown that increasing the bench length and delaying the second primary support time makes the second primary support safer, but if the bench length was too long or the second primary support time was too late, then the tunnel supporting structure failed. In the model test of this study, a middle bench length of 20.4 m and a second primary support time of 28 days were more satisfactory. [ABSTRACT FROM AUTHOR]

As a zero-carbon fuel, hydrogen is considered a promising alternative fuel. Hydrogen flames can be greatly affected by intrinsic instabilities including the diffusional-thermal instability (DTI) and Darrieus-Landau instability (DLI). Therefore, it is important to understand their properties, especially for cryogenic flames that are related to the safe utilization of liquid hydrogen. In this work, we conduct two-dimensional simulations of unsteady hydrogen/air conical flames to assess the effects of intrinsic instabilities, DTI and DLI, on the response of premixed hydrogen/air conical flames to inlet flow perturbations. The equivalence ratio and initial temperature are changed to respectively achieve different Lewis numbers (related to DTI) and expansion ratios (related to DLI). It is found that under certain conditions flame pinch-off occurs, during which a separated flame pocket is formed by the strong amplification of flame wrinkles generated by the inlet flow perturbations. The underlying mechanism of flame pinch-off enhancement due to DTI and DLI is different. For fuel-lean hydrogen/air at normal temperature, the flame front wrinkling is enhanced by strong DTI and it is the stretch-chemistry interaction that leads to flame pinch-off. However, for stoichiometric hydrogen/air at cryogenic temperature, there is a strong effect of DLI and flame pinch-off is mainly induced by flame-flow interaction. Moreover, downstream flow and flame speed near the separated flame pocket for flames exhibiting strong DTI and DLI are compared and the difference is analyzed. The findings indicate that intrinsic flame instability can amplify flame wrinkling and fluctuations in heat release rate, thereby contributing to flame pinch-off. [ABSTRACT FROM AUTHOR]