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A proper inflammatory response is critical to the restoration of tissue homeostasis after injury or infection, but how such a response is modulated by the physical properties of the cellular and tissue microenvironments is not fully understood. Here, using H358, HeLa, and HEK293T cells, we report that cell density can modulate inflammatory responses through the Hippo signaling pathway. We found that NF-κΒ activation through the proinflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor α (TNFα) is not affected by cell density. However, we also noted that specific NF-κΒ target genes, such as cyclooxygenase 2 (COX-2), are induced much less at low cell densities than at high cell densities. Mechanistically, we observed that the transcriptional coactivators Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) are localized to the nucleus, bind to TEA domain transcription factors (TEADs), recruit histone deacetylase 7 (HDAC7) to the promoter region of COX-2, and repress its transcription at low cell density and that high cell density abrogates this YAP/TAZ-mediated transcriptional repression. Of note, IL-1β stimulation promoted cell migration and invasion mainly through COX-2 induction, but YAP inhibited this induction and thus cell migration and invasion. These results suggest that YAP/TAZ-TEAD interactions can repress COX-2 transcription and thereby mediate cell density-dependent modulation of proinflammatory responses. Our findings highlight that the cellular microenvironment significantly influences inflammatory responses via the Hippo pathway.

This paper solves an accurate fixed-time attitude and position control problems of a quadrotor UAV system. The aircraft system is subject to nonlinearities, parameter uncertainties, unmodeled dynamics, and external time-varying disturbances. To deal with the under-actuation problem of the quadrotor’s dynamics, a hierarchical control structure with an inner–outer loop framework is adopted for the flight control system design. Robust nonlinear control strategies for attitude and position control are innovatively proposed based on a new continuous nonsingular terminal sliding mode control (CNTSMC) scheme. A full-order homogeneous terminal sliding surface is designed for the attitude and position states in such a way that the sliding motion is fixed-time stable independently of the system’s initial condition. Hence, this contributes to enhancing the control system robustness. A disturbance observer-based control (DOBC) approach is developed to stabilize the inner rotational subsystem (attitude-loop). This compounded control structure integrates a finite-time observer (FTO) and the CNTSMC scheme. The FTO observer is incorporated into the control framework to cope with the strong perturbations. An output-feedback control approach is adopted for the outer translational subsystem (position-loop) to ensure a velocity-free control. In this context, the CNTSMC scheme is combined with a fixed-time extended state observer (FXESO) to achieve an active disturbance rejection control (ADRC) by estimating and canceling the lumped disturbances. Therefore, within the developed control approach including the robust CNTSMC scheme, DOBC, and ADRC strategies, robust and accurate trajectory tracking control can be achieved despite uncertainties and disturbances. Stability analysis of the closed-loop system is rigorously investigated by using the Lyapunov theorem, bi-limit homogeneous theory, and the notion of input-to-state stability (ISS). Extensive experimental tests under the influence of various disturbances are conducted to corroborate the theoretical findings. To this end, an effective model-based design (MBD) framework is established to implement the developed control algorithms in real autopilot hardware. Furthermore, processor-in-the-loop (PIL) experiments are also carried out within the MBD framework. A comparative study is made involving our control algorithms and other control strategies. Overall, the obtained results show that the synthesized control system yields performance improvement regarding fixed-time tracking stability featuring fast transient, strong robustness, and high steady-state precision. Besides, the chattering effect of regular linear sliding mode control (LSMC) is significantly alleviated. Moreover, unlike conventional TSMC, the control input shows no singularity.

In this research, the inclusion ratios and inclusion constants of MCT-β-CD/PERM and MCT-β-CD/CYPERM inclusion complexes were measured by UV–vis and fluorescence spectroscopy. The inclusion ratios are both 1:1, and the inclusion constants are 60 and 342.5 for MCT-β-CD/PERM and MCT-β-CD/CYPERM, respectively. The stabilities of inclusion complexes were investigated by MD simulation. MD shows that VDW energy plays a vital role in the stability of inclusion complex, and the destruction of inclusion complex is due to the increasing temperature. The UV–vis absorption spectra of MCT-β-CD and its inclusion complexes were studied by time-dependent density functional theory (TDDFT) method employing BLYP-D3, B3LYP-D3 and M06-2X-D3 functionals. BLYP-D3 well reproduces the UV–vis absorption spectrum and reveals that the absorption bands of MCT-β-CD mainly arise from n → π ∗ and n → σ ∗ transition, and those of inclusion complexes mainly arise from intramolecular charge transfer (ICT). ICT results in the shift of main absorption bands of MCT-β-CD.

A detailed analysis of the vibrational spectra of 8,8a,9,10,11,12,12a,13-octahydrodibenzo[b,h][1,4,7,10] dioxadiazacyclododecine-7,14 (6H,15H)-dione has been conducted in harmonic and anharmonic approximation. B3LYP and B3LYP-D3 functionals and 6-31G(d), 6-31+G(d,p) and TZVP basis set were employed. The calculated frequencies were compared with experimental fundamentals and the error distribution was analysis by Root Mean Square Deviation (RMSD). When a relatively large basis set (6-31+G(d,p)) is adopted, anharmonic approximation presents a overall advantage than empirical scaling factor method, when a medium basis set (6-31G(d)) is adopted, empirical scaling factor method provides a better accuracy than anharmonic approximation, except for ν (CH 2 ) and ν (CH) mode. Anharmonic approximation cannot reduce the large errors of ν (N H), δ (N H) and ν (C O) modes. The bimolecular model reveals that these errors mainly arise from intermolecular hydrogen bonds. Van der Waals correction on DFT makes a significant improvement on prediction of ν (CH 2 ) and ν (CH) modes but a negligible change on the other modes.

Polystyrene is a common substrate material for protein adsorption in biosensors and bioassays. Here, we present a new method for multilayered, site-directed immobilization of antibody on polystyrene surface through the linkage of a genetically engineered ligand and the assembly of staphylococcal protein A (SPA) with immunoglobulin G (IgG). In this method, antibodies were stacked on polystyrene surface layer by layer in a potential three-dimensional way and exposed the analyte-binding sites well. Enzyme-linked immunosorbent assay (ELISA) revealed that the new method showed a 32-fold higher detection sensitivity compared with the conventional one. Pull-down assay and Western blot analysis further confirmed that it is different from the ones of monolayer adsorption according to the comparison of adsorption capacity. The differentiated introduction of functional ligands, which is the key of this method, might offer a unique idea as a way to interfere with the dynamic behavior of a protein complex during the process of adsorption.

A comparative study of DFT and DFT-D3 has been carried out on the UV-vis absorption of permethrin, cypermethrin and their β-cyclodextrin inclusion complexes. The TDDFT method with PCM (or COSMO) model was adopted and B3LYP, BLYP and BLYP-D3 functionals were selected. Comparing the simulated spectra with experimental one, we can notice that pure BLYP functional can better reproduce the UV-vis spectra than hybrid B3LYP, but empirical dispersion corrections BLYP-D3 has better performance than BLYP. BLYP-D3 calculations reveal that the main absorption bands of permethrin and cypermethrin arise from the π→π(*) transition, after encapsulated by β-CD to form inclusion complexes, the host-guest intermolecular charge transfer (ICT) makes the main absorption bands to be changed significantly in wavelength and intensity.

The relationship between Solidago canadensis L. invasion and soil microbial communities was studied across the invasive gradients varying from 0 to 40, 80, and 100% coverage of S. canadensis. The results showed both soil microbial biomass C (Cmic) and N (Nmic) increased as the coverage of S. canadensis increased. Soil microbial quotient Cmic/Corg (microbial biomass C/organic C) tended to increase linearly with the coverage of S. canadensis. Soil basal respiration (BR) also showed a similar trend. The soil respiratory quotient qC02 decreased with S. canadensis invasion, and remained at quite a constantly low level in the invasive soils. Sole carbon source utilization profiles analyses indicated that S. canadensis invasion tended to result in higher microbial functional diversity in the soil. Average utilization of specific substrate guilds was highest in the soil with S. canadensis monoculture. Principle component analysis of sole carbon source utilization profiles further indicated that microbial functional diversity in the soil with S. canadensis monoculture was distinctly separated from those soils in the native area and the ecotones. In conclusion, S. canadensis invasion improved soil microbial biomass, respiration and utilization of carbon sources, and decreased qC02, thus created better soil conditions, which in turn were more conducive to the growth of S. canadensis.

Thin film is one of the important geometric configurations in the microelectronic devices. The traditional theories for heterogeneous material are challenged for their application to the thin film configurations (the free-standing and substrate-attached thin films). In the present paper, a finite element analysis with a statistic procedure is proposed to estimate the effective properties of thin films. For the free-standing thin film, the effective stiffness decreases as film thickness decreases. Comparison is made between numerical simulations and analytical solutions derived from a plane stress self-consistent scheme. For the substrate-attached thin film, the effective stiffness is affected by the relative stiffness of the substrate to the film. The numerical simulation shows the effective stiffness of the substrate-attached thin film can vary between the equivalent value of the free-standing thin film and Voigt bound. The three-dimensional Hashin–Shtrikman bounds fail to gauge the effective stiffness of thin film.

In the present study, a finite element scheme with random distribution strategy is employed to systematically investigate the modulus difference of polycrystalline copper aggregates in different geometrical configurations (three-dimensional bulk and thin film configurations). Firstly, the finite element simulation is performed to estimate the effective elastic constants in three-dimensional bulk configuration. The numerical estimations are in good agreement with the existing analytical solutions and experimental measurements. Secondly, the proven finite element scheme is extended to the prediction of the effective moduli of the free-standing and substrate-attached thin films. For the free-standing thin film, the effective Young's modulus decreases with reducing the film thickness. For the substrate-attached thin film, its effective modulus is affected by the relative stiffness between the substrate and the film. The spread of the effective moduli in different configurations could be as large as 20%.

Nano-phase nickel hydroxide samples were prepared by a method combining supersonic and coordination–precipitation methods. The samples exhibit β-phase Ni(OH) 2 through X-ray diffraction analysis. It is shown that the grain size with the irregular grain shape is about 40 nm and ranges from 20 to 50 nm through transmission electron microscopy. Clustering phenomena were observed. The positive electrode discharge test made of a mixture of micrometer sized spherical Ni(OH) 2 and nano-phase Ni(OH) 2 was carried out. The results showed that the capacity of the electrode can be increased by about 14% when the nano-phase Ni(OH) 2 doped concentration is 8 wt%. X-ray photoelectron spectroscopy analysis indicates that nano-phase Ni(OH) 2 can increase the transformation between Ni 3+ and Ni 2+ in the charge–discharge cycle when the nano-phase Ni(OH) 2 is doped, and as a result the utilization of active material on the positive electrode is improved.