Tissue engineering is an important field of regenerative medicine, which combines scaffolds and cell transplantation to develop substitute tissues and/or promote tissue regeneration. Hydrogels, a ...three-dimensional network with high water content and biocompatibility, have been widely used as scaffolds to mimic the structure and properties of tissues. However, the low mechanical strength and limited functions of traditional hydrogels greatly limited their applications in tissue engineering. Recently, nanocomposite hydrogels, with its advantages of high mechanical property and some unique properties (such as electrical conductivity, antibacterial, antioxidation, magnetic responsiveness), have emerged as the most versatile and innovative technology, which provides a new opportunity as a unique tool for fabricating hydrogels with excellent properties. In this review, we summarize the recent advances in fabricating nanocomposite hydrogels and their applications in tissue engineering. In addition, the future and prospects of nanocomposite hydrogels for tissue engineering are also discussed.
Various nanomaterials and polymer chains were combined to form nanocomposite hydrogels for different types of tissue engineering.
Pancreatic adenocarcinoma (PAAD) is a pancreatic disease with a high mortality rate in the world. This present research intends to identify the function of lncRNA LINC00857/miR-340-5p/Transforming ...growth factor alpha (TGFA) in the progression of PAAD.
Bioinformatics analysis was used to explore the differentially expressed lncRNA/miRNA/mRNA and analyze the relationship between lncRNA/miRNA/mRNA expression and prognosis of PAAD by enquiring TCGA, GEO and GTEX. KEGG pathway analysis and GO enrichment analysis were implemented to annotate the crucial genes regulated by LINC00857. The biological behaviors of PAAD cells were detected by CCK-8, colony formation and transwell assays. Interactive associations between LINC00857 and miR-340-5p, as well as miR-340-5p and TGFA were analyzed by dual luciferase assay.
By enquiring TCGA database, we got that LINC00857 was highly expressed in patients with PAAD and positively associated with worse prognosis in PAAD patients. Moreover, LINC00857 upregulation promoted the proliferation and clone formation abilities of PAAD cells. Afterwards, the downstream miRNA and mRNA targets of LINC00857 were picked up to construct a ceRNA network. Further study revealed that TGFA expression was positively regulated by LINC00857 and negatively regulated by miR-340-5p. Besides that, the inhibitory effect of miR-340-5p on PAAD cells growth and movement can be blocked by LINC00857 upregulation. While, the malignant behavior of PAAD cells induced by TGFA overexpression can be eliminated by LINC00857 knockdown.
Upregulation of LINC00857 improved growth, invasion and migration abilities of PAAD cells by modulation of miR-340-5p/TGFA, affording potential targets and biomarkers for the clinical diagnosis and treatment.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Fracture propagation, fracture coalescence, and their interactions with the bedding plane in layered rocks are of great significance when conducting a stability analysis of structures on or within ...the layered rock mass. In this work, we developed a numerical model by the inserted cohesive element (CE) method to simulate the evolution of fracture paths in layered rocks, then validated it with modified wedge splitting tests. The results indicate that the fracture penetration/deflection behaviour at the bedding plane is controlled by two strength thresholds of the bedding plane: 1) If the bedding plane strength > threshold I — the fracture directly penetrates the bedding plane; and 2) If threshold I > bedding plane strength > threshold II — first, the fracture deflects along the bedding plane without any daughter fractures or penetration, and then one or two daughter fractures can form. A two-flawed model is used to simulate the fracture coalescence. The fracture coalescence is first determined by the bedding plane's strength thresholds. If bedding plane strength > threshold I, fracture coalescence can occur only if the second flaw is located within a certain range. No coalescence occurs if the bedding plane strength < threshold II. If the bedding plane strength is between threshold I and threshold II, the coalescence is further controlled by the location of the second flaw. The second flaw seems to induce the fracture to deflect further along the bedding plane.
•A numerical model based on the inserted CZM method is developed.•Fracture/bedding plane interaction in layered rocks is investigation.•The conditions for fracture coalescence are discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Uncertainty of geomechanical parameters is an important consideration for rock engineering and has a very important influence on safety evaluation, design, and construction. Back analysis is a common ...method of determining geomechanical parameters but traditional deterministic back analysis cannot allow for consideration of this uncertainty. In this study, a new probabilistic back analysis method is proposed that integrates Bayesian methods and a multi-output support vector machine (B–MSVM). In this B–MSVM back analysis method, Bayesian was used to deal with the uncertainty of geomechanical parameters and a multi-output support vector machine (MSVM) was adopted to build the relationships between displacements and those parameters. The proposed method was applied to a high abutment rock slope at the Longtan hydropower station, China. At Longtan, the uncertainty of the two types of geomechanical parameters, Young's modulus and lateral pressure coefficients of in situ stress, were modeled as random variables. Based on the parameters identified by probabilistic back analysis, the computed displacements agreed closely with the measured displacement data monitored in the field. The result showed that B–MSVM presented the uncertainty of the geomechanical parameters reasonably. Further study indicated that the performance of B–MSVM could be improved greatly by updating field monitoring information regularly. The proposed method provides a significant new approach for probabilistic back analysis and contributes to the determination of realistic geomechanical parameters.
•Probabilistic model for identification of rock mechanical parameters.•Bayesian method for considering uncertainty of slope engineering.•Probabilistic back analysis integrating Bayesian and a multi-output SVM.•Performance will be improved by continuously updating slope displacements.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Layered oxides widely used as lithium-ion battery electrodes are designed to be cycled under conditions that avoid phase transitions. Although the desired single-phase composition ranges are well ...established near equilibrium, operando diffraction studies on many-particle porous electrodes have suggested phase separation during delithiation. Notably, the separation is not always observed, and never during lithiation. These anomalies have been attributed to irreversible processes during the first delithiation or reversible concentration-dependent diffusion. However, these explanations are not consistent with all experimental observations such as rate and path dependencies and particle-by-particle lithium concentration changes. Here, we show that the apparent phase separation is a dynamical artefact occurring in a many-particle system driven by autocatalytic electrochemical reactions, that is, an interfacial exchange current that increases with the extent of delithiation. We experimentally validate this population-dynamics model using the single-phase material Li
(Ni
Mn
Co
)O
(0.5 < x < 1) and demonstrate generality with other transition-metal compositions. Operando diffraction and nanoscale oxidation-state mapping unambiguously prove that this fictitious phase separation is a repeatable non-equilibrium effect. We quantitatively confirm the theory with multiple-datastream-driven model extraction. More generally, our study experimentally demonstrates the control of ensemble stability by electro-autocatalysis, highlighting the importance of population dynamics in battery electrodes (even non-phase-separating ones).
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GEOZS, IJS, IMTLJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZAGLJ
Using a framework of partial differential equation-constrained optimization, we demonstrate that multiple constitutive relations can be extracted simultaneously from a small set of images of pattern ...formation. Examples include state-dependent properties in phase-field models, such as the diffusivity, kinetic prefactor, free energy, and direct correlation function, given only the general form of the Cahn-Hilliard equation, Allen-Cahn equation, or dynamical density functional theory (phase-field crystal model). Constraints can be added based on physical arguments to accelerate convergence and avoid spurious results. Reconstruction of the free energy functional, which contains nonlinear dependence on the state variable and differential or convolutional operators, opens the possibility of learning nonequilibrium thermodynamics from only a few snapshots of the dynamics.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
MCF7 cells have been used as an experimental model for breast cancer for decades. Typically, a culture medium is designed to supply cells with the nutrients essential for their continuous ...proliferation. Each medium has a specific nutritional composition. Therefore, cells cultured in different media may exhibit differences in their metabolism. However, only a few studies have investigated the effects of media on cells. In this study, we compared the effects of Dulbecco's modified Eagle medium (DMEM) and minimum essential medium alpha modification (αMEM) on MCF7 cells. The two media differentially affected the morphology, cell cycle, and proliferation of MCF7 cells, but had no effect on cell death. Replacement of DMEM with αMEM led to a decrease in ATP production and an increase in reactive oxygen species production, but did not affect the cell viability. RNA-sequencing and bioinformatic analyses revealed 721 significantly upregulated and 1247 downregulated genes in cells cultured in αMEM for 48 h compared with that in cells cultured in DMEM. The enriched gene ontology terms were related to mitosis and cell proliferation. Kyoto encyclopedia of genes and genomes analysis revealed cell cycle and DNA replication as the top two significant pathways. MCF7 cells were hypoxic when cultured in αMEM. These results show that the culture medium considerably affects cultured cells. Thus, the stability of the culture system in a study is very important to obtain reliable results.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•The spatial and temporal variation of ecosystem service value (ESV) was reflected.•Identifying key influencing factors of ESV by using Deep Forest model.•The PLUS model was used to simulate the ...future trends of ESV under five SSPs scenarios.
The ecosystem services value (ESV) is an important basis for measuring ecological environment quality and efficient management of ecosystems. Although there have been many studies devoted to the measurement of ESV, the research on the key influencing factors of ESV and the prediction of future development scenarios is still limited. This study coupled the Deep Forest model and Patch-generating Land Use Simulation (PLUS) model to identify the key factors of ESV, and simulated the change trend of ESV under the Shared Socioeconomic Pathways (SSPs). Taking the cluster cities around the Yellow River floodplain area as the research object, this study quantitatively analyzed the spatiotemporal evolution characteristics of its ESV from 2000 to 2020, and identified the key factors affecting ESV using the Deep Forest model. The results showed that: (1) The ESV showed an overall upward trend from 2000 to 2020, with strong spatial heterogeneity; (2) The key factors affecting ESV were construction land ratio, distance to railway, SHDI, etc.; (3) The best development pathway of ESV in 2025, 2030 and 2035 would be SSPs5, SSPs2 and SSPs4 respectively. This study can provide theoretical support for the management of maximizing the overall benefits of ecosystem services in the study area.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Methylation of cytosines is a major epigenetic modification in mammalian genomes. The levels and patterns of DNA methylation are the results of the opposing actions of methylating and demethylating ...machineries. Over the past two decades, great progress has been made in elucidating the methylating machinery including the identification and functional characterization of the DNA methyltransferases (Dnmts). However, the mechanisms of demethylation and the major players involved had been elusive. A major breakthrough came in 2009, when the ten-eleven translocation (Tet) family of proteins was discovered as 5-methylcytosine (5mC) dioxygenases that convert 5mC to 5-hydroxymethylcytosine (5hmC). Studies in the past several years have established that 5hmC serves as an intermediate in DNA demethylation and that Tet proteins have important roles in epigenetic reprogramming in early embryos and primordial germ cells. In this review, we discuss recent advances in this exciting field, focusing on the role of Tet proteins in mammalian development.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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