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Fine-grained soils containing diatom microfossils of biological origin are found worldwide. However, although these soils are acknowledged to have unique physical and mechanical properties, the exact role of diatoms in determining their compression and hydraulic behaviours remains unclear, especially when high effective stress is involved, and the underlying micromechanism is yet to be revealed. This study investigated the compression and permeability of diatomaceous soils prepared by mixing pure diatom and kaolin powders through one-dimensional constant rate of strain compression tests with a maximum vertical stress of 10 MPa. The microstructure of the soils studied was observed by atomic force microscopy, scanning electron microscopy and mercury intrusion porosimetry, and the microstructural evolution during compression was traced. The results indicate that the special hollow structure of diatom particles with internal pores contributes significantly to the high void ratio, compressibility and permeability of diatomaceous soils, and increasing the diatom content improves the pore distribution non-uniformity of the diatom–kaolin mixtures. In addition, the diatom particles have high brittleness and breakage potential, leading to microstructural rearrangement during compression, especially pore-structure adjustment. Lower compressive stress deforms the inter- and intra-aggregate pores, but higher vertical stress damages the diatoms' hollow structure, which changes the compression and hydraulic parameters in a different manner from the case of conventional clay. This paper enriches the knowledge concerning the multilevel behaviour of fine-grained soils containing diatom microfossils and provides a fundamental dataset. [ABSTRACT FROM AUTHOR]

The mechanical characteristics of the soil–structure interface have a crucial impact on the bearing capacity of offshore foundations. The thixotropy-induced strength recovery of remolded soils has a significant effect on the increase in the stability of the foundation. To explore the effects of thixotropy on the recovery characteristics of the soil–structure interfacial shear strength, a self-designed interfacial mechanical characteristic apparatus is designed in this study to perform a series of soil–structure interface tests on clays from the South China Sea and offshore Dalian, respectively. The relationship between the recovery of undrained shear strength and the change of interfacial shear strength is analyzed by the index of shear-resistant coarseness. And the effect mechanism of thixotropy on interfacial shear strength is discussed from the microscopic view. The test results indicated that the rate of increase of the soil–structure interfacial shear strength is higher than that of the undrained shear strength. The particle size index of the soil was found to significantly influence the strength recovery characteristics of the soil–structure interface. A higher clay content will accelerate the development of the interfacial shear strength. This article provides a deep insight into the thixotropic effect on the mechanical properties of the marine soil–structure interface. [ABSTRACT FROM AUTHOR]

Rosmarinic acid (RA) is a natural phenolic compound extracted from the Labiatae family and is a natural antioxidant. In this study, walnut oil added with RA was treated with different ultraviolet radiations, and stabilization effects in terms of the same conditions (0.2 mg/g) were compared with synthetic antioxidant (BHT). In order to compare the effectiveness of three UV treatments, different lab tests were conducted, namely, the acid value, peroxide value, iodine value, anisidine value, DPPH free radical scavenging rate, and malondialdehyde content. The enhanced UV-A, UV-B, and UV-C radiation intensities have increased the oxidation stability of RA-added walnut oil, of which UV-B has the greatest influence on the oxidative stability of walnut oil. When both RA and BHT were added at 0.2 mg/g, the antioxidant effect of RA is superior to the general antioxidant BHT. [ABSTRACT FROM AUTHOR]

Generating strong adhesion by engineered proteins has the potential for high technical applications. Current studies of adhesive proteins are primarily limited to marine organisms, e.g., mussel adhesive proteins. Here, we present a modular engineering strategy to generate a type of exotic protein adhesives with super strong adhesion behaviors. In the protein complexes, the lanmodulin (LanM) underwent α‐helical conformational transition induced by lanthanides, thereby enhancing the stacking density and molecular interactions of adhesive protein. The resulting adhesives exhibited outstanding lap‐shear strength of ≈31.7 MPa, surpassing many supramolecular and polymer adhesives. The extreme temperature (−196 to 200 °C) resistance capacity and underwater adhesion performance can significantly broaden their practical application scenarios. Ex vivo and in vivo experiments further demonstrated the persistent adhesion performance for surgical sealing and healing applications. [ABSTRACT FROM AUTHOR]

The HT ht value versus time of clays is shown in Fig. When the HT ht value is equal to 100%, it means the strength of soil has recovered its original intact shear strength. The regained strength of YS-1 clay is also considerable, and the value of HT ht is greater than 40% after 2 months. By contrast, the HT ht of YS-2 and ES-2 clays in the corresponding deep layer is much lower (see Table 1 in the original paper). [Extracted from the article]

The exponential growth of the total amount of global data presents a huge challenge to mainstream storage media. The emergence of molecular digital storage inspires the development of the new‐generation higher‐density digital data storage. In particular, DNA with high storage density, reproducibility, and long recoverable lifetime behaves the ideal representative of molecular digital storage media. With the development of DNA synthesis and sequencing technologies and the reduction of cost, DNA digital storage has attracted more and more attention and achieved significant breakthroughs. Herein, this Review briefly describes the workflow of DNA storage, and highlights the storage step of DNA digital data storage. Then, according to different information storage forms, the current DNA information encryption methods are emphatically expounded. Finally, the brief perspectives on the current challenges and optimizing proposals in DNA information preservation and encryption are presented. [ABSTRACT FROM AUTHOR]

The inherently tenuous adhesion strength and limited environmental tolerance of supramolecular adhesives severely restrict their application scenarios. It is challenging for the development of robust adhesives with extreme temperature tolerance. Herein, we report a new type of temperature‐resistant crown‐ether‐protein (CEP) adhesive by harnessing synergistic host–guest molecular interactions between engineered crown ether and protein building blocks. The outputs of CEP adhesive demonstrate ultrahigh shearing adhesion strength of ≈22 MPa over a wide temperature range from −196 to 200 °C, superior to other established supramolecular or polymeric adhesives. The temperature‐induced phase transition and internal bound water stabilized the system and led to superb adhesion under extreme conditions. Thus, this work pioneers a molecular engineering approach for the generation of adhesives with tailored applications in extreme settings. [ABSTRACT FROM AUTHOR]

Thixotropy is a very important and unique property of soft clay in engineering, which has been drawing more and more attention in recent years. This study investigated the thixotropic strength recovery of representative marine clays in different sites of offshore China. The microstructure changes of clay during thixotropy were observed using scanning electron microscopy, and then related microscopic characteristics were analyzed. Probability entropy, Ep , is proposed as a new indicator based on the statistics of the alteration of diameter and orientation of particles or aggregates. The results show that thixotropy had significant effect on the strength increase for all the offshore Chinese clays that were tested, but their strength regain with time varied between the different sites. Some good correlations were developed between the thixotropy strength ratio and index parameters, particularly for water content, plasticity index, liquidity index, and sensitivity. The microstructural evolution of the clay tested during thixotropy was characterized by the change in both the diameter and the arrangement of particles or aggregates. The probability entropy was proved to quantitatively describe and analyze the microstructural evolution during thixotropy of clay, and its value increases with time. This new indicator could help to provide deeper insight into the thixotropic mechanism of clay. [ABSTRACT FROM AUTHOR]

This paper presents an investigation on the microstructural evolution alongside the strength degradation of the soft marine soil under T-bar cyclic penetration. The marine soil that was recovered from the seabed in deep-water areas in the South China Sea can be representative of the characteristics of typical soft marine clay in this water area. The microstructure of clayed soils is characterized by particle-constituted aggregates and interaggregate pores, which is commonly considered to predominate the strength of soils. To quantitatively capture the evolving microstructural characteristics of the soil during loading, a new indicator (i.e., probability entropy, H) is proposed based on statistics of the alteration in aggregate size and orientation of the soil. With the aid of the new indicator, the soil microstructural evolution is further evaluated and associated with strength degradation during the continuous T-bar cyclic loading course. In addition, through a comparison between the intact marine soil samples and reconstituted ones, the effect of microstructural cementation of marine soil is examined on the shearing strength during the cyclic loading. The two types of soil samples show a significantly different evolving trend of microstructure. The probability entropy of intact soil decreases, while that of reconstituted soil increases. Thus, the intact soil exhibits a higher probability degree of entropy change than does the reconstituted soil. This result may provide a plausible explanation for the difference in strength between the intact soils and reconstituted ones, even if they have been subjected to the same consolidation stress condition. The novel quantitative method to evaluate the soil microstructure can be further applied to understand the mechanism of strength degradation of soft marine soils. This will provide a deeper insight to the engineering properties of those marine soils, which will facilitate a precise design for practical offshore foundations in deep waters. [ABSTRACT FROM AUTHOR]

Information storage based on DNA molecules provides a promising solution with advantages of low‐energy consumption, high storage efficiency, and long lifespan. However, there are only four natural nucleotides and DNA storage is thus limited by 2 bits per nucleotide. Here, artificial nucleotides into DNA data storage to achieve higher coding efficiency than 2 bits per nucleotide is introduced. To accommodate the characteristics of DNA synthesis and sequencing, two high‐reliability encoding systems suitable for four, six, and eight nucleotides, i.e., the RaptorQ‐Arithmetic‐LZW‐RS (RALR) and RaptorQ‐Arithmetic‐Base64‐RS (RABR) systems, are developed. The two concatenated encoding systems realize the advantages of correcting DNA sequence losses, correcting errors within DNA sequences, reducing homopolymers, and controlling specific nucleotide contents. The average coding efficiencies with error correction and without arithmetic compression by the RALR system using four, six, and eight nucleotides reach 1.27, 1.61, and 1.85 bits per nucleotide, respectively. While the average coding efficiencies by the RABR system are up to 1.50, 2.00, and 2.35 bits per nucleotide, respectively. The coding efficiency, versatility, and tunability of the developed artificial DNA systems might provide significant guidance for high‐reliability and high‐density data storage. [ABSTRACT FROM AUTHOR]

Degradable bioplastics have attracted growing interest worldwide. However, it is challenging to develop bioplastics with a simple processing procedure, strong mechanical performance, good biocompatibility, and adjustable physicochemical properties. Herein, we introduced structural proteins as building blocks and developed a simple environmentally friendly approach to fabricate diverse protein‐based plastics. A cost‐effective and high‐level production approach was developed through batch fermentation of Escherichia coli to produce the biomaterials. These bioplastics possess super plasticity, biocompatibility, biodegradability, and high resistance to organic solvents. Their structural and mechanical properties can be precisely controlled. Besides, high density information storage and hemostatic applications were realized in the bioplastic system. The customizable bioplastics have great potential for applications in numerous fields and are capable to scale up to the industrial level. [ABSTRACT FROM AUTHOR]

The development of new storage media to meet the demands for diverse information storage scenarios is a great challenge. Here, a series of lanthanide‐based luminescent organogels with ultrastrong mechanical performance and outstanding plasticity are developed for patterned information storage and encryption applications. The organogels possessing outstanding mechanical properties and tunable luminescent colors are prepared by electrostatic and coordinative interactions between natural DNA, synthetic ligands, and rare earth (RE) ions. The organogel‐REs can be stretched by 180 times and show an ultrastrong breaking strength of 80 MPa. A series of applications with both information storage and encryption, such as self‐information pattern, quick response (QR) code, and barcode, are successfully demonstrated by the organogel‐REs. The developed information storage systems have various advantages of good processability, high stretchability, excellent stability, and versatile design of information patterns. Therefore, the organogel‐RE‐based information storage systems are suitable for applications under different scenarios, such as flexible devices under repeating rude operations. The advancements will enable the design and development of luminescent organogel‐REs as information storage and encryption media for various scenarios. [ABSTRACT FROM AUTHOR]

This paper presents an experimental investigation on the ultra-soft marine soil recovered from the seabed in deep-water areas in South China Sea (SCS). An improved T-bar penetrometer is made and employed in laboratory to measure the undrained shear strength of the soils and its degradation with the penetration cycles. A further investigation on the microstructure of the marine soils during the cyclic penetration has been conducted. The findings indicate that there is a kind of "crust zone" existing in the upper layer of seabed sediment. The reasons of this "crust zone" are further interpreted. By comparing the intact and remoulded samples, it is found that the former exhibits a higher strength degradation degree than that of the latter. This discrepancy in shear strength degradation between the two kinds of samples can be attributed to the microstructure changes. During the cyclic penetration process, the natural flocculated structure of intact soil samples collapses with the breakage of particle aggregates, and a further destruction of large-sized inter-particle pores occurs. As far as the remoulded soil samples, their microstructures experience a continuing fracturing course starting with a dense packing of soil particles and followed by a progressive development of the loose packing state. [ABSTRACT FROM AUTHOR]

In this study, poly-L-lactic acid micropillar substrates were fabricated to evaluate the influence of topographic substrates on cell morphological and functional characteristics, such as spreading area, voltage-gated calcium channels (VGCCs) and membrane potential. The proliferation, spreading area, perimeter and circularity of SH-SY5Y cells interfaced with different substrates were first investigated. In addition, the cytoskeleton and focal adhesion of a cell as important manifestations of cell morphology were analyzed by immunofluorescence. VGCC responsiveness was evaluated by measuring the dynamic changes in intracellular Ca2+ evoked by 50 mM extracellular K+. To determine study whether the differences in VGCC responsiveness were caused by the differences in VGCC gene expression, the expression of N/L- type VGCCs was determined by qPCR and fluorescence staining. Notably, improved measurement of the membrane potential with potentiometric fluorescent dye TMRM was applied to determine the membrane potential of SH-SY5Y cells. Results indicated that the SH-SY5Y cells were deformed significantly to adapt to the substrates; however, no distinct effect on the proliferative ability of SH-SY5Y cells was observed. The micropillar substrates markedly influenced VGCC responsiveness, which correlated strongly with cell spreading but not with VGCC expression. The resting membrane potential of SH-SY5Y cells cultured on different substrates also changed, but no effect on responsiveness of VGCC was observed. These results suggest that the effect of the micropillar substrates on cell VGCC responsiveness may be attributed to changes in the functionality of the ion channel itself. Thus, topographic substrates can be used to engineer cell functionality in cell-based drug screening. [ABSTRACT FROM AUTHOR]

The characterization of the geological and geotechnical properties of marine sediments is crucial for the exploration of subsea oil and gas resources. In this study, the engineering properties of deep-water soils recovered from the South China Sea (SCS) were in detail characterized via a series of laboratory tests to explore their physical, mechanical, mineralogical and microstructural behaviors. The results show that the index properties of deep-water soils are characterized by high natural water content, high void ratio, high Atterberg limits, but low density. The sensitivity of these soils is higher than 10, indicating their strong natural structure, which significantly controls the shear behavior and failure model. The intact samples show strain-softening to strain-hardening behavior with an increase in the confining pressure, while reconsolidated samples consistently show strain-hardening phenomenon under any level of confining pressure. The cyclic T-bar penetration tests show a dramatic strength degradation behavior of the intact samples. The compression curves of the intact samples always lie above the remoulded ones, and there is an obvious yielding phenomenon for the intact samples. The deep-water soils exhibit high thixotropy, as proposed by a criterion to evaluate the thixotropic capacity of soils. The mineralogy and microstructure analysis indicate that biogenic silica and an open flocculated structure might be the underlying reasons for the unique physical and mechanical properties of deep-water soils. The findings through this study provide essential parameters for related engineering applications and a deeper insight into understanding the unique properties of deep-water soils. • A comprehensive investigation on the geotechnical characterization of deep-water soils was carried out. • The index and mechanical properties of deep-water soils were evaluated by laboratory tests. • The mechanism of the unique geotechnical behaviors of deep-water soils was revealed from the perspective of mineralogy and microstructure. [ABSTRACT FROM AUTHOR]

The offshore wind farm industry in China has been growing exponentially in recent years, and suction bucket foundations are increasingly applied as an effective solution. This paper presents a comprehensive site investigation and outlines the key soil parameters for offshore suction bucket foundation design, by taking the Houhu wind farm in southern China as an example. The in-situ cone penetrometer (CPTU) tests and sampling borehole were carried out to investigate the geotechnical features of soils. The soil conditions are characterized by multilayers and complicated sediment components. The classification and mechanical properties, such as stress history, static and cyclic shear strengths, and shear modulus of soils were obtained and compared by CPTU interpretation and advanced laboratory tests. Then the probable foundation optimization design solution from the perspective of soil parameters in the light of set up effect and cyclic behavior was discussed and highlighted. Based on the experience of this project and other projects in offshore China, some common challenges were summarized and the relative recommendations were proposed finally. The main objective of this study is to provide more reliable guidance of geotechnical investigation for the rapid development of wind farms in offshore China. • A comprehensive site investigation was carried out for the offshore suction bucket foundation design in southern China. • The classification and mechanical properties of soils were obtained and compared by CPTU interpretation and advanced laboratory tests. • The probable foundation optimization design solution was discussed and highlighted. [ABSTRACT FROM AUTHOR]

Generating strong adhesion by engineered proteins has the potential for high technical applications. Current studies of adhesive proteins are primarily limited to marine organisms, e.g., mussel adhesive proteins. Here, we present a modular engineering strategy to generate a type of exotic protein adhesives with super strong adhesion behaviors. In the protein complexes, the lanmodulin (LanM) underwent α-helical conformational transition induced by lanthanides, thereby enhancing the stacking density and molecular interactions of adhesive protein. The resulting adhesives exhibited outstanding lap-shear strength of ≈31.7 MPa, surpassing many supramolecular and polymer adhesives. The extreme temperature (-196 to 200 °C) resistance capacity and underwater adhesion performance can significantly broaden their practical application scenarios. Ex vivo and in vivo experiments further demonstrated the persistent adhesion performance for surgical sealing and healing applications., (© 2023 Wiley-VCH GmbH.)

The inherently tenuous adhesion strength and limited environmental tolerance of supramolecular adhesives severely restrict their application scenarios. It is challenging for the development of robust adhesives with extreme temperature tolerance. Herein, we report a new type of temperature-resistant crown-ether-protein (CEP) adhesive by harnessing synergistic host-guest molecular interactions between engineered crown ether and protein building blocks. The outputs of CEP adhesive demonstrate ultrahigh shearing adhesion strength of ≈22 MPa over a wide temperature range from -196 to 200 °C, superior to other established supramolecular or polymeric adhesives. The temperature-induced phase transition and internal bound water stabilized the system and led to superb adhesion under extreme conditions. Thus, this work pioneers a molecular engineering approach for the generation of adhesives with tailored applications in extreme settings., (© 2022 Wiley-VCH GmbH.)

DNA has attracted increasing interest as an appealing medium for information storage. However, target-specific rewriting of the digital data stored in intracellular DNA remains a grand challenge because the highly repetitive nature and uneven guanine-cytosine content render the encoded DNA sequences poorly compatible with endogenous ones. In this study, a dual-plasmid system based on gene editing tools was introduced into Escherichia coli to process information accurately. Digital data containing large repeat units in binary codes, such as text, codebook, or image, were involved in the realization of target-specific rewriting in vivo, yielding up to 94% rewriting reliability. An optical reporter was introduced as an advanced tool for presenting data processing at the molecular level. Rewritten information was stored stably and amplified over hundreds of generations. Our work demonstrates a digital-to-biological information processing approach for highly efficient data storage, amplification, and rewriting, thus robustly promoting the application of DNA-based information technology.

Degradable bioplastics have attracted growing interest worldwide. However, it is challenging to develop bioplastics with a simple processing procedure, strong mechanical performance, good biocompatibility, and adjustable physicochemical properties. Herein, we introduced structural proteins as building blocks and developed a simple environmentally friendly approach to fabricate diverse protein-based plastics. A cost-effective and high-level production approach was developed through batch fermentation of Escherichia coli to produce the biomaterials. These bioplastics possess super plasticity, biocompatibility, biodegradability, and high resistance to organic solvents. Their structural and mechanical properties can be precisely controlled. Besides, high density information storage and hemostatic applications were realized in the bioplastic system. The customizable bioplastics have great potential for applications in numerous fields and are capable to scale up to the industrial level., (© 2022 Wiley-VCH GmbH.)

Cellular collective motion in confluent epithelial monolayers is involved in many processes such as embryo development, carcinoma invasion, and wound healing. The development of new chemical strategies to achieve large-scale control of cells' collective motion is essential for biomedical applications. Here a series of DNA nanostructures with different dimensions were synthesized and their influences on cells' collective migration and packing behaviors in epithelial monolayers were investigated. We found that the framed DNA nanoassemblies effectively reduced the cells' speed by increasing the rigidity of cells, while the lipid-DNA micelles had a more pronounced effect on cells' projection area and shape factor. These DNA nanostructures all significantly enhanced the dependence of cells' speed on their shape factor. Our results indicate that cells' mobility in monolayers can be manipulated by chemical intercellular interactions without any genetic intervention. This may provide a new chemical strategy for tissue engineering and tumor therapy., Competing Interests: The authors declare that they have no conflicts of interest in this work., (© 2022 The Authors. Publishing Services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd.)

Polypeptides consisting of amino acid (AA) sequences are suitable for high-density information storage. However, the lack of suitable encoding systems, which accommodate the characteristics of polypeptide synthesis, storage and sequencing, impedes the application of polypeptides for large-scale digital data storage. To address this, two reliable and highly efficient encoding systems, i.e. RaptorQ-Arithmetic-Base64-Shuffle-RS (RABSR) and RaptorQ-Arithmetic-Huffman-Rotary-Shuffle-RS (RAHRSR) systems, are developed for polypeptide data storage. The two encoding systems realized the advantages of compressing data, correcting errors of AA chain loss, correcting errors within AA chains, eliminating homopolymers, and pseudo-randomized encrypting. The coding efficiency without arithmetic compression and error correction of audios, pictures and texts by the RABSR system was 3.20, 3.12 and 3.53 Bits/AA, respectively. While that using the RAHRSR system reached 4.89, 4.80 and 6.84 Bits/AA, respectively. When implemented with redundancy for error correction and arithmetic compression to reduce redundancy, the coding efficiency of audios, pictures and texts by the RABSR system was 4.43, 4.36 and 5.22 Bits/AA, respectively. This efficiency further increased to 7.24, 7.11 and 9.82 Bits/AA by the RAHRSR system, respectively. Therefore, the developed hexadecimal polypeptide-based systems may provide a new scenario for highly reliable and highly efficient data storage., Competing Interests: The authors declare that they have no conflicts of interest in this work., (© 2021 The Authors. Publishing Services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd.)

In this study, poly-L-lactic acid micropillar substrates were fabricated to evaluate the influence of topographic substrates on cell morphological and functional characteristics, such as spreading area, voltage-gated calcium channels (VGCCs) and membrane potential. The proliferation, spreading area, perimeter and circularity of SH-SY5Y cells interfaced with different substrates were first investigated. In addition, the cytoskeleton and focal adhesion of a cell as important manifestations of cell morphology were analyzed by immunofluorescence. VGCC responsiveness was evaluated by measuring the dynamic changes in intracellular Ca 2+ evoked by 50 mM extracellular K + . To determine study whether the differences in VGCC responsiveness were caused by the differences in VGCC gene expression, the expression of N/L- type VGCCs was determined by qPCR and fluorescence staining. Notably, improved measurement of the membrane potential with potentiometric fluorescent dye TMRM was applied to determine the membrane potential of SH-SY5Y cells. Results indicated that the SH-SY5Y cells were deformed significantly to adapt to the substrates; however, no distinct effect on the proliferative ability of SH-SY5Y cells was observed. The micropillar substrates markedly influenced VGCC responsiveness, which correlated strongly with cell spreading but not with VGCC expression. The resting membrane potential of SH-SY5Y cells cultured on different substrates also changed, but no effect on responsiveness of VGCC was observed. These results suggest that the effect of the micropillar substrates on cell VGCC responsiveness may be attributed to changes in the functionality of the ion channel itself. Thus, topographic substrates can be used to engineer cell functionality in cell-based drug screening.