Foundation soil of offshore structures may be subjected to various non-proportional cyclic loadings, such as wave loading, tide loading and earthquake loading. The consolidation state may affect the ...undrained behaviour of clay under pure rotation of principal stress directions. A series of cyclic undrained torsional tests were performed on normally and over consolidated clay subjected to pure rotation of principal stress directions at constant deviatoric stress conditions. The effects of over consolidation ratio (OCR) on the excess pore water pressure, stress-strain loop, stiffness and non-coaxial behaviour of the clay were analyzed under different deviatoric stresses and intermediate principal stress coefficients (b values). The results indicate that owing to the pure principal stress rotation alone, strain and excess pore water pressure accumulated in samples and the accumulation is affected by OCRs, deviatoric stress amplitudes and b values. Negative excess pore water pressure and stress dilatancy can be observed in over consolidated clay. Compared with shear stiffness, the normal differential stiffness experiences greater degradation under the pure rotation of principal stress. The shear stiffness of over consolidated clay may show an increase with loading cycles, while the normal differential stiffness degrades at low deviatoric stress value. Over consolidated clay shows non-coaxial behaviour and the greater the OCR values or the smaller the deviatoric stress, the larger the non-coaxial angle. The effects of b values on the non-coaxial behaviour of over consolidated clay are also observed.
HIGHLIGHTS
Over-consolidated clay subjected to pure rotation of principal stress.
The effects of OCR, deviatoric stress and b value were analyzed.
Negative EPWP and stress dilatancy were observed in over consolidated clay.
The greater the OCR, the larger the non-coaxial angle.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Programmed death ligand-1 (PD-L1) is highly expressed in a variety of cancer cells and suggests a poorer prognosis for patients. The natural compound isorhamnetin (ISO) shows promise in treating ...cancers and causing damage to canine mammary tumor (CMT) cells. We investigated the mechanism of ISO in reducing PD-L1 expression in CMT cells. Clustered, regularly interspaced short palindromic repeat-associated protein 9 (CRISPR/Cas9) was used to mediate
knockout in U27 cells. Then, monoclonal cells were screened and cultured. Nucleotide sequencing and expression of PD-L1 were detected. Additionally, we examined cell migration, invasion, and damage. Immunofluorescent staining of PD-L1 was examined in U27 cells. The signaling pathways were measured by Western blotting. Murine xenotransplantation models and murine immunocompetent allograft mammary tumor models were established to evaluate the effect of ISO therapy. Expression of Ki-67, caspase3, and PD-L1 were analyzed by immunohistochemistry. A pull-down assay was used to explore which proteins could bind to ISO. Canine EGFR protein was purified and used to detect whether it directly binds to ISO using a surface plasmon resonance assay. ISO inhibited the EGFR-STAT3-PD-L1 signaling pathway and blocked cancer growth, significantly increasing the survival rate of healthy cells. The cell membrane receptor EGFR was identified as a direct target of ISO. ISO could be exploited as an antineoplastic treatment of CMT by targeting EGFR to suppress PD-L1 expression.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Little has been known about symbiotic relationships and host specificity for symbionts in the human gut microbiome so far. Bifidobacteria are a paragon of the symbiotic bacteria biota in the human ...gut. In this study, we characterized the population genetic structure of three bifidobacteria species from 58 healthy mother–infant pairs of three ethnic groups in China, geographically isolated, by Rep-PCR, multi-locus sequence analysis (MLSA), and in vitro carbohydrate utilization. One hundred strains tested were incorporated into 50 sequence types (STs), of which 29 STs, 17 STs, and 4 STs belong to B. longum subsp. longum , B. breve , and B. animalis subsp. lactis , respectively. The conspecific strains from the same mother–child pair were genetically very similar, supporting the vertical transmission of Bifidobacterium phylotypes from mother to offspring. In particular, results based on allele profiles and phylogeny showed that B. longum subsp. longum and B. breve exhibited considerable intraspecies genetic heterogeneity across three ethnic groups, and strains were clustered into ethnicity-specific lineages. Yet almost all strains of B. animalis subsp. lactis were incorporated into the same phylogenetic clade, regardless of ethnic origin. Our findings support the hypothesis of co-evolution between human gut symbionts and their respective populations, which is closely linked to the lifestyle of specific bacterial lineages. Hence, the natural and evolutionary history of Bifidobacterium species would be an additional consideration when selecting bifidobacterial strains for industrial and therapeutic applications.
In offshore engineering, the sand beneath an embankment may be subjected to traffic loads, resulting in a series of engineering issues. The behaviour of the sand beneath the embankment may change ...under a long-term traffic load. A series of drained cyclic and post-cyclic monotonic triaxial tests were performed on Fujian sand with different relative densities. The drained strength and stress–dilatancy behaviours were studied. The results indicated that the normalised peak strength ratio after cyclic loading was greater than that without cyclic loading, depending on the cyclic stress amplitude, while the critical state strength seemed to be only slightly affected by the cyclic loading history. The dilative response of sand could also be influenced by cyclic loading-induced fabric. Under constant relative density conditions, the higher the cyclic stress amplitude applied to the sand sample, the larger the volume strain produced in the critical state. Furthermore, cyclic-induced fabric could be destroyed after 6% axial strain.
Social robots may become an innovative means to improve the well-being of individuals. Earlier research has shown that people easily self-disclose to a social robot, even in cases where it was ...unintended by the designers. We report on an experiment considering self-disclosing in a diary journal or to a social robot after negative mood induction. An off-the-shelf robot was complemented with our in-house developed AI chatbot, which could talk about ‘hot topics’ after training it with thousands of entries on a complaint website. We found that people who felt strongly negative after being exposed to shocking video footage benefited the most from talking to our robot, rather than writing down their feelings. For people less affected by the treatment, a confidential robot chat or writing a journal page did not differ significantly. We discuss emotion theory in relation to robotics and possibilities for an application in design (the emoji-enriched ‘talking stress ball’). We also underline the importance of otherwise disregarded outliers in a data set of therapeutic nature.
Multi-agent reinforcement learning encounters a non-stationary challenge, where agents concurrently update their policies, leading to changes in the environment. Existing approaches have tackled this ...challenge through communication among agents to obtain their partners’ actions, but this introduces computational complexity known as partner sample complexity. An alternative approach is to develop partner models that generate samples instead of direct communication to mitigate this complexity. However, a discrepancy arises between the real policies distribution and the policy of partner models, termed as model bias, which can significantly impact performance when heavily relying on partner models. In order to achieve a trade-off between sample complexity and performance, a novel multi-agent model-based reinforcement learning algorithm called decentralized adaptive partner modeling (DAPM) is proposed, which utilizes fictitious self play (FSP) to construct partner models and update policies. Model bias is addressed by establishing an upper bound to restrict the usage of partner models. Coupled with that, an adaptive rollout approach is introduced, enabling real agents to dynamically communicate with partner models based on their quality, ensuring that agent performance can progressively improve with partner model samples. The effectiveness of DAPM is exhibited in two multi-agent tasks, showing that DAPM outperforms existing model-free algorithms in terms of partner sample complexity and training stability. Specifically, DAPM requires 28.5% fewer communications compared to the best baseline and exhibits reduced fluctuations in the learning curve, indicating superior performance.
Stimuli‐responsive supercapacitors have attracted broad interest in constructing self‐powered smart devices. However, due to the demand for high cyclic stability, supercapacitors usually utilize ...stable or inert electrode materials, which are difficult to exhibit dynamic or stimuli‐responsive behavior. Herein, this issue is addressed by designing a MoS2@carbon core‐shell structure with ultrathin MoS2 nanosheets incorporated in the carbon matrix. In the three‐electrode system, MoS2@carbon delivers a specific capacitance of 1302 F g−1 at a current density of 1.0 A g−1 and shows a 90% capacitance retention after 10 000 charging‐discharging cycles. The MoS2@carbon‐based asymmetric supercapacitor displays an energy density of 75.1 Wh kg−1 at the power density of 900 W kg−1. Because the photo‐generated electrons can efficiently migrate from MoS2 nanosheets to the carbon matrix, the assembled photo‐responsive supercapacitor can answer the stimulation of ultraviolet‐visible‐near infrared illumination by increasing the capacitance. Particularly, under the stimulation of UV light (365 nm, 0.08 W cm−2), the device exhibits a ≈4.50% (≈13.9 F g−1) increase in capacitance after each charging‐discharging cycle. The study provides a guideline for designing multi‐functional supercapacitors that serve as both the energy supplier and the photo‐detector.
An in situ approach based on the coordination between boronate ester polymers and metal ions has been developed to generate ultrathin MoS2 nanosheets in the carbon matrix, affording MoS2@carbon core‐shell particles. Due to the synergistic effect between the semiconductor MoS2 and the multi‐element co‐doped carbon matrix, MoS2@carbon exhibits outstanding capacitive performance and light‐triggered reversible capacitance evolution.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A comprehensive understanding of the mechanisms of battery is essential for the design of thermal management systems. In this work, a second-order equivalent circuit model considering the hysteresis ...effect of the battery was developed, and a combined EIS and HPPC characterization method was used for parameter identification. The results showed that the combining EIS and HPPC parameter measurement methods could extract and analyze the parameters of the battery with different time scales and improve the accuracy of the model. It was found that the polarization internal resistance (R1 and R2) of the battery shows a stronger temperature dependence than the ohmic internal resistance at low temperatures, with R1 being about 170 times higher at low temperatures (10 °C) than high temperatures (50 °C). At the same temperature, τ2 was approximately 100 times larger than τ1, which was two orders of magnitude difference between τ1 and τ2. In addition, the dynamic heat generation results showed that the heat generation rate of the battery increases with decreasing temperature. At 3C discharge rate, the heat generation rate of the battery at low temperature (−10 °C) was about 1.5 times higher than at room temperature (25 °C).
•The time-scale information in the battery is extracted and analyzed.•Relationships between internal parameters and kinetic processes were established.•The dynamic heat generation process of the battery was studied.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
To enhance the performance of microchannel heat sinks, secondary channels or ribs are oftenused separately. However, the synergistic enhancement of heat dissipation by secondary channels and ...individually composite with different types of ribs and the factors influencing them are not yet clear. In this study, the numerical simulation software ANSYS Fluent is used for simulation and obtaining the optimal microchannel heat sink structure from diamond, rectangular, back triangular, front triangular and elliptical ribs with secondary channel composite. Firstly, the results show that overall performance of microchannel heat sink with front triangular ribs with secondary channel composite is better than other designs. Secondly, the optimized microchannel heat sink with front triangular ribs and secondary channels outperforms the conventional microchannel heat sink by up to 34% in terms of overall performance when Reynolds number is 200, relative rib width/rib length is 0.633/0.400 and relative secondary channel width is 0.600. Finally, by sensitivity analysis, it is found the effect of relative rib width on heat dissipation is about 60%, the effect of flow rate on pressure drop is about 40%, and the effect of overall performance on relative rib width and relative secondary channel width are about 26% and 25%, respectively.
•The heat transfer mechanism of composite microchannels is studied by Heat Transfer.•The optimal rib shape is obtained by comprehensive performance.•The relevant parameters are optimized to obtain the best composite microchannel.•Maximum factors affecting heat transfer, pressure and overall factor are obtained.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
Data usually resides on a manifold, and the minimal dimension of such a manifold is called its intrinsic dimension . This fundamental data property is not considered in the generative adversarial ...network (GAN) model along with its its variants; such that original data and generated data often hold different intrinsic dimensions . The different intrinsic dimensions of both generated and original data may cause generated data distribution to not match original data distribution completely, and it certainly will hurt the quality of generated data. In this study, we first show that GAN is often unable to generate simulation data, holding the same intrinsic dimension as the original data with both theoretical analysis and experimental illustration. Next, we propose a new model, called Hausdorff GAN, which removes the issue of different intrinsic dimensions and introduces the Hausdorff metric into GAN training to generate higher quality data. This provides new insights into the success of Hausdorff GAN. Specifically, we utilize a mapping function to map both original and generated data into the same manifold. We then calculate the Hausdorff distance to measure the difference between the mapped original data and the mapped generated data, toward pushing generated data to the side of original data. Finally, we conduct extensive experiments (using MNIST, CIFAR10, and CelebA datasets) to demonstrate the significant performance improvement of the Hausdorff GAN in achieving the largest Inception Score and the smallest Frechet inception distance (FID) score as well as producing diverse generated data at different resolutions.
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