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The dynamic mechanical strength of the extracellular matrix (ECM) has been demonstrated to play important role in determining the cell behavior. Growing evidences suggest that the gradual stiffening process of the matrix is particularly decisive during tissue development and wound healing. Herein, a novel strategy to prepare hydrogels with gradually enhanced mechanical strength is provided. Such hydrogels could maintain the dynamic properties at their initial states, such as self‐healing and shear‐thinning properties. With subsequent slow covalent crosslinking, the stability and mechanical properties would be gradually improved. This method is useful for sequence programmability and oxidation strategies, which has provided an alternated tool to study cell behavior during dynamic increase in mechanical strength of ECM. [ABSTRACT FROM AUTHOR]

The formation water characteristics are closely related to hydrocarbon migration and accumulation. The main factors affecting differences of the formation water from the Yan'an and Fuxian Formations are analyzed, based on the vertical and plane distribution characteristics of water type and hydrochemical composition of the formation water. The relationship between formation water characteristics and reservoir distribution and formation is discussed, and the factors that are important to in the process of finding Jurassic reservoirs are clarified in this paper. Study of formation water of the lower Jurassic Yan'an and Fuxian Formations in the Ordos basin reveal the complexity and regularity of the hydrochemical characteristics. The complexity lies in the diversity of formation water and the hydrochemical parameters, such as water salinity, sodium chloride coefficient, metamorphism coefficient, etc., which vary significantly vertically or laterally. The regularity is reflected in that the varying formation hydrochemistry forms zonation, vertically, east-westward, or geomorphologically. It is pointed out that: 1) The mixing and alternation of formation water in different hydrological cycles lead to the vertical differentiation of formation water chemical characteristics. From Fuxian to Y10 to Y9 strata, the salinity of the formation water gradually decreases, the proportion of CaCl2 type water gradually decreases, and the proportion of NaHCO3 type and Na2SO4 type formation water gradually increases. The coefficient of sodium chloride and desulfurization gradually increase, while the coefficient of metamorphism decreases. 2) Structural evolution determines the east-west zonation of the hydrochemical characteristics. The Jurassic strata at the east or west margin of the basin are buried shallowly or exposed where infiltration water supply alternates easily with a relative lower salinity, and the strata at or close to the axis of the Tianhuan depression are buried deeply far away from the supply area, imprisoned in a relatively stagnant environment, making the salinity relatively high. 3) Regionalization of the formation hydrochemical feature changes with geomorphology of the Fuxian Formation-Yan10 member and is strengthened by the water-rock reaction during the diagenesis process. In the river developed area, formation water salinity is low. In the direction of the slope, terrace, and highland, it increases gradually, while the coefficient of the sodium chloride and desulfurization decreases, and the coefficient of metamorphism increases by degrees. Formation water type changes from Na2SO4 or NaHCO3 to CaCl2. 4) The terraces, slopes, and channel bars have the advantage of reservoir formation in terms of the infiltration water alternating extent, hydrodynamics, lithologic association, and low-amplitude structural trap development conditions, and they are the favorable targets prediction method of Jurassic Palaeogeomorphic reservoir is summarized. [ABSTRACT FROM AUTHOR]

As the largest inland oil-bearing basin in China, the Tarim Basin is a large-scale composite basin that has experienced a complex tectonic evolutionary history from the Ediacaran to the Cenozoic. From the Ediacaran to the Ordovician, the Tarim Basin was in an extensional tectonic environment. From the Silurian to the Devonian, the Tarim Block switched from the presence of passive margins to active margins along its northern and southern edges, eventually colliding with the North Kunlun Terrane in the Silurian. From the Carboniferous to the Triassic, the transition of the Tarim Block from an independent landmass to an internal component of the Eurasian Plate resulted from collisions with the Yili-Central Tianshan Terrane to the north during the Late Carboniferous and the Qiangtang Terrane to the south during the Triassic. From the Jurassic to the Paleogene, several unconformities developed because of the subduction of the Meso-Tethys oceanic plate during the Late Jurassic and the Neo-Tethys oceanic plate during the Paleogene. After the Neogene, as a rejuvenated foreland basin, the Tarim Basin was activated along its margins and became an intermountain basin due to the intense regional compression induced by the Indian Plate. Based on a seismic profile cross-section of the basin, we conclude that the extension and shortening in the profile reflects the block amalgamation history and the structural evolution of the Tarim Basin. The structural-sedimentary evolution of this basin is closely related to the movement of the peripheral plates. [ABSTRACT FROM AUTHOR]

We propose a new perovskite/carbon composite of LaMnO 3 nanoparticles anchored on N and P co-doped porous carbon as an efficient electrocatalyst for oxygen reduction reaction (ORR) in alkaline solution. A facile two-step method is applied for the synthesis of such composite, involving the pyrolysis of cheap, abundant and renewable natural okara with the formation of N and P co-doped porous carbon for the first step, and the deposition of LaMnO 3 nanoparticles on the carbon surface by sol-gel synthesis at the second step. A synergistic effect is built between the LaMnO 3 nanoparticles and the porous carbon substrate, resulting in obviously improved ORR activity as compared with the individual N, P co-doped carbon and the nanosized LaMnO 3 electrocatalysts, in terms of onset potential, limiting current density, and stability. The LaMnO 3 /N, P co-doped carbon composites further evaluated as an air electrode in a Zn-air battery, demonstrating attractive performance, including high discharge voltage plateau (∼1.2 V) and excellent stability with negligible degradation in voltage at 25 mA cm −1 discharge current for 24 h. The present results highly promise the LaMnO 3 /biocarbon nanocomposite as a potential metal-free ORR electrocatalyst, which may find a wide use in metal-air batteries or fuel cells. [ABSTRACT FROM AUTHOR]

Functional appendage regeneration is essential for skin rehabilitation, but it has always failed by current existing healing approaches, owing to their inefficacy in preventing disfiguring scars. In this study, a novel regeneration-directing artificial skin (RDAS) system is presented, which is based on the rational design of multi-layered hydrogels that closely mimic natural skin matrices. By leveraging the programmability and architectural rigidity of DNA components, without the need for exogenous cell transplantation, such RDAS effectively minimizes tissue fibrosis by accurately guiding the regenerative process in wound fibroblasts, enabling rapid scarless wound repair, restoration of dermal function, and successful in situ regeneration of multiple appendages, such as hair follicles (HFs), sebaceous glands (SGs), and sweat glands (SwGs). Therefore, the RDAS offers a cell-free antiscarring therapeutic strategy for regenerative wound healing, resulting in improved outcomes. This innovative approach holds great potential for future clinical applications and burn rehabilitation., (© 2024 Wiley‐VCH GmbH.)

DNA hydrogels have attracted increasing attention owing to their excellent permeability and high mechanical strength, together with thixotropy, versatile programmability and good biocompatibility. However, the moderate biostability and immune stimulation of DNA have arisen as big concerns for future potential clinical applications. Herein, we report the self-assembly of a novel l-DNA hydrogel, which inherited the extraordinary physical properties of a d-DNA hydrogel. With the mirror-isomer deoxyribose, this hydrogel exhibited improved biostability, withstanding fetal bovine serum (FBS) for at least 1 month without evident decay of its mechanical properties. The low inflammatory response of the l-DNA hydrogel has been verified both in vitro and in vivo. Hence, this l-DNA hydrogel with outstanding biostability and biocompatibility can be anticipated to serve as an ideal 3D cell-culture matrix and implanted bio-scaffold for long-term biomedical applications., (© 2022 Wiley-VCH GmbH.)

Objective: From the previous comparative genomic analysis, we found a specific unknown 10 kb sequence (including 11 Open reading Frames) in Chinese piscine strain GD201008-001 genome. To study the role of 10 kb in the pathogenicity of piscine S. agalactiae, the 10 kb sequence was deleted from the GD201008-001 genome., Methods: The isogenic mutant Δ10 kb was constructed by using the temperature-sensitive Streptococcus-E. coli shuttle vector pSET4s. We compared the growth characteristics, adherence to HEp-2 cell and bacterial virulence in a zebrafish infection model between wild strain and mutant. Meanwhile the expressions of the known virulence genes from GD201008-001 and Δ10 kb were also quantified by real-time PCR., Results: The Δ10 kb showed no significant differences in bacterial morphology and adherence to HEp-2 cells compared with the wild-type strain, but the speed of growth was slightly slower than the wild strain. Furthermore the 50% lethal dose of Δ10 kb was decreased up to 10-fold (P < 0.001) of the parental strain in a zebrafish infection model, and the expressions of the virulence genes, PI-2b and neul, were significantly increased in the mutant., Conclusion: These findings demonstrated that the 10 kb sequence of piscine Streptococcus agalactiae exerts a significant effect on bacterial virulence and probably regulates the virulence genes expression of GD20 1008-001.