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Taking the specific geometry and gesture of the diamond grains into consideration, a novel simulation model to predict the machined surface topography in grinding of superalloy (GH4169) is presented, where the arrangements of abrasive grains and the plowing induced pile-up ridges are also integrated. Based on the designed surface topography of the grains arrayed brazed diamond wheels, the grinding wheel was firstly reconstructed according to the following factors of the abrasive grains, including the shape, dimension, protrusion height, attitude, and position. In accordance with the kinematics of the grains, the pile-up ridges corresponding to the real-time depth of cut were then achieved, and the superposition resulting from the interference of successive abrasive particles was thoroughly discussed to simulate the final ground topography accurately. Finally, the grinding experiments at the selected parameters were undertaken to verify the proposed model, where the measured and simulated surface topography and the surface statistics (Sa, Sq) were investigated and compared. The favorable accordance between the simulated and experimental results indicated the accuracy and the practicability of the proposed model for optimizing the grain arrangement in the diamond wheel design and improving the grinding surface uniformity. [ABSTRACT FROM AUTHOR]

By introducing some parameters perturbed by white noises, we propose a class of stochastic inertial neural networks in random environments. Constructing two Lyapunov–Krasovskii functionals, we establish the mean-square exponential input-to-state stability on the addressed model, which generalizes and refines the recent results. In addition, an example with numerical simulation is carried out to support the theoretical findings. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the most common and most lethal malignant tumors in the world. Microvascular invasion (MVI) is a major risk factor for survival outcomes and intrahepatic metastasis after resection in patients with HCC. Relevant English literatures retrieved using PubMed on the research progress of MVI in patients with HCC were reviewed. For HCC patients, especially those with MVI, it is very important to develop a comprehensive and sequential treatment plan to support the long-term survival of patients. This manuscript reviewed and analyzed the risk factors for MVI; the preoperative prediction of MVI, which informs the selection of surgical strategies; and the current situation and future direction of comprehensive postoperative treatment strategies; to provide a basis for the comprehensive treatment of HCC patients with MVI. For HCC patients with MVI, the preoperative prediction of MVI may play a certain guiding role in planning procedures, and the comprehensive sequential postoperative pathological detection of HCC MVI may provide a basis for treatment decisions. [ABSTRACT FROM AUTHOR]

The thermal stability of lead-free perovskite ceramics (1-x)Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)TiO3 (BZT–xBCT) is enhanced greatly by co-sintering different combinations in rhombohedral phase (R phase), tetragonal phase (T phase) and morphotropic phase boundary (MPB), respectively. By co-sintering the mixture of BZT–0.2BCT (R) and BZT–0.8BCT (T) powders with molar ratio of 1:1 at the optimized condition of 1250 °C for 2 h, its thermal stability is increased by 46% compared with the recognized ceramic of BZT–0.5BCT (MPB). Furthermore, the ceramic obtained by co-sintering the mixture of BZT–0.2BCT, BZT–0.5BCT and BZT–0.8BCT powders with molar ratio of 1:1:1 shows the further improved thermal stability by 63% compared with the recognized ceramic of BZT–0.5BCT. The finding reveals that co-sintering different phases to enhance the thermal stability of ceramics may provide a broad prospect for the application of lead-free perovskite ceramics. [ABSTRACT FROM AUTHOR]

We study the dynamical Casimir–Polder force on a two-level atom with different initial states in the one-dimensional dielectric cavity with output coupling, and obtain the analytical expression of the expectation value of dynamical Casimir–Polder force. Results show that the expectation values of dynamical Casimir–Polder force may be affected by the initial states of the atom. Moreover, the expectation value of Casimir–Polder force may vanish at some special atomic positions by properly selecting the initial state of the system. The effects of different relative dielectric constants and the cavity size on the expectation value of Casimir–Polder force are also discussed. [ABSTRACT FROM AUTHOR]

Considering stochastic perturbations of white and color noises, we introduce the Markov switched stochastic Nicholson-type delay system with patch structure. By constructing a traditional Lyapunov function we show that solutions of the addressed system are not only positive, but also do not explode to infinity in finite time and, in fact, are ultimately bounded. Then we estimate its ultimate boundedness, moment, and Lyapunov exponent. Finally, we present an example of numerical simulations to verify theoretical results. [ABSTRACT FROM AUTHOR]

Highlights: A new type of protein nanostructure as a chemodynamic therapy nanoagent was fabricated via proper assembling and crosslinking techniques. The as-fabricated nanostructures could cross the blood–brain barrier, possessing excellent long circulating times and accumulation properties at the tumor site. The RBC@Hb@GOx NPs can be regarded as ‘pure particles of drugs,’ which can produce toxic reactive oxygen species to inhibit the growth of orthotopic brain tumor.Glioblastoma (GBM) remains a formidable challenge in oncology. Chemodynamic therapy (CDT) that triggers tumor cell death by reactive oxygen species (ROS) could open up a new door for GBM treatment. Herein, we report a novel CDT nanoagent. Hemoglobin (Hb) and glucose oxidase (GOx) were employed as powerful CDT catalysts. Instead of encapsulating the proteins in drug delivery nanocarriers, we formulate multimeric superstructures as self-delivery entities by crosslinking techniques. Red blood cell (RBC) membranes are camouflaged on the protein superstructures to promote the delivery across blood–brain barrier. The as-prepared RBC@Hb@GOx nanoparticles (NPs) offer superior biocompatibility, simplified structure, and high accumulation at the tumor site. We successfully demonstrated that the NPs could efficiently produce toxic ROS to kill U87MG cancer cells in vitro and inhibit the growth of GBM tumor in vivo, suggesting that the new CDT nanoagent holds great promise for treating GBM. [ABSTRACT FROM AUTHOR]

Most of the aircraft skin is assembled by riveted structural parts, and the riveted holes are prone to cracks due to stress concentration, so it is urgent to carry out non-destructive testing research on aircraft riveted components. In this paper, a planar remote-field eddy current focusing detection probe was designed to study the hidden defects around the holes of aircraft riveted components, and a 3D simulation model was established for the detection of hidden defects in aircraft riveted components. The structural parameters of the focused remote-field eddy current probe were optimized by combining simulation and experiment, and the planar remote-field eddy current focusing detection test was carried out. The simulation and results showed that: When the inclination angle of the excitation coil is 10° and the coil spacing is 0 mm, the optimized focused remote-field eddy current probe can effectively detect the defect in length × width × depth of 10 mm × 0.2 mm × 1 mm under the buried depth of 9 mm. When the buried depth of the defect is 6–9 mm, the focused remote-field eddy current probe has a better detection capability than the non-focused remote-field eddy current probe. [ABSTRACT FROM AUTHOR]

By using the Krasnoselskii fixed point theorem in a cone, we investigate the existence of two positive periodic solutions of the generalized delay differential neoclassical growth model with periodic coefficients and delays. Moreover, we give an example to demonstrate the theoretical result. [ABSTRACT FROM AUTHOR]

The paper is concerned with periodic solutions of a model of gene regulatory system with time-varying coefficients and delays. We establish some sufficient conditions for the existence, positivity, and permanence of solutions, which help to derive the global exponential stability of positive periodic solutions for this model. Our method depends on differential inequality technique and Lyapunov functional. At last, we give an example and its numerical simulations to verify theoretical results. [ABSTRACT FROM AUTHOR]

A detailed study of the structural, electronic, and optical absorption properties of crystalline 1,4-dinitrofurazano[3,4-b]piperazine (DNFP) under hydrostatic pressures of 0-100 GPa was performed using periodic density functional theory. As the pressure increases, the lattice constants and cell volumes calculated by LDA gradually approach those obtained by GGA-PW91. It was found that the structure of DNFP is much stiffer in the b direction than along the a and c axes, indicating that the compressibility of the crystal is anisotropic. As the pressure increases, the band gap gradually decreases, and this decrease is more pronounced in the low-pressure range than in the high-pressure region. An analysis of the density of states showed that the electronic delocalization in DNFP gradually increases under the influence of pressure. DNFP exhibits relatively high optical activity at high pressure. As the pressure increases, the bands in the fundamental absorption region of the absorption spectrum of DNFP become more numerous and intense. [ABSTRACT FROM AUTHOR]

Highlights: A new type of protein nanostructure as a chemodynamic therapy nanoagent was fabricated via proper assembling and crosslinking techniques. The as-fabricated nanostructures could cross the blood–brain barrier, possessing excellent long circulating times and accumulation properties at the tumor site. The RBC@Hb@GOx NPs can be regarded as 'pure particles of drugs,' which can produce toxic reactive oxygen species to inhibit the growth of orthotopic brain tumor. Glioblastoma (GBM) remains a formidable challenge in oncology. Chemodynamic therapy (CDT) that triggers tumor cell death by reactive oxygen species (ROS) could open up a new door for GBM treatment. Herein, we report a novel CDT nanoagent. Hemoglobin (Hb) and glucose oxidase (GOx) were employed as powerful CDT catalysts. Instead of encapsulating the proteins in drug delivery nanocarriers, we formulate multimeric superstructures as self-delivery entities by crosslinking techniques. Red blood cell (RBC) membranes are camouflaged on the protein superstructures to promote the delivery across blood–brain barrier. The as-prepared RBC@Hb@GOx nanoparticles (NPs) offer superior biocompatibility, simplified structure, and high accumulation at the tumor site. We successfully demonstrated that the NPs could efficiently produce toxic ROS to kill U87MG cancer cells in vitro and inhibit the growth of GBM tumor in vivo, suggesting that the new CDT nanoagent holds great promise for treating GBM. [ABSTRACT FROM AUTHOR]

Focusing on delay differential neoclassical growth model in random environments, we introduce the stochastic model to describe the dynamics of the long-run behavior of the economy with a parameter perturbed by white noises. We prove that the global positive solution exists uniquely and estimate its ultimate boundedness in mean and sample Lyapunov exponent. Finally, some numerical tests are given to illustrate theoretical results. [ABSTRACT FROM AUTHOR]

Ischemic stroke produces the highest adult disability. Despite successful recanalization, no-reflow, or the futile restoration of the cerebral perfusion after ischemia, is a major cause of brain lesion expansion. However, the vascular mechanism underlying this hypoperfusion is largely unknown, and no approach is available to actively promote optimal reperfusion to treat no-reflow. Here, by combining two-photon laser scanning microscopy (2PLSM) and a mouse middle cerebral arteriolar occlusion (MCAO) model, we find myogenic vasomotion deficits correlated with post-ischemic cerebral circulation interruptions and no-reflow. Transient occlusion-induced transient loss of mitochondrial membrane potential (ΔΨm) permanently impairs mitochondria-endoplasmic reticulum (ER) contacts and abolish Ca2+ oscillation in smooth muscle cells (SMCs), the driving force of myogenic spontaneous vasomotion. Furthermore, tethering mitochondria and ER by specific overexpression of ME-Linker in SMCs restores cytosolic Ca2+ homeostasis, remotivates myogenic spontaneous vasomotion, achieves optimal reperfusion, and ameliorates neurological injury. Collectively, the maintaining of arteriolar myogenic vasomotion and mitochondria-ER contacts in SMCs, are of critical importance in preventing post-ischemic no-reflow. The no-reflow phenomenon after stroke is attributed to damaged spontaneous vasomotion of cerebral arterioles, which can be alleviated by maintaining mitochondria-ER contact-dependent Ca2+ oscillation. [ABSTRACT FROM AUTHOR]

This paper proposes a semiparametric time-dependent jump diffusion model in an effort to capture the dynamic behavior of short-term interest rates. The newly proposed model includes a wide variety of well-known interest rate models, incorporating the time-varying instantaneous return, volatility as well as jump component. The local likelihood density estimation technique together with pseudo likelihood estimation method is employed to estimate the parameters of the model. Some simulations are conducted to examine the statistical performance of our estimators. The proposed procedure is then applied to analyze daily federal funds rate. [ABSTRACT FROM AUTHOR]

The therapeutic potential of recombinant cytokines has been limited by the severe side effects of systemic administration. We describe a strategy to reduce the dose-limiting toxicities of monomeric cytokines by designing two components that require colocalization for activity and that can be independently targeted to restrict activity to cells expressing two surface markers. We demonstrate the approach with a previously designed mimetic of cytokines interleukin-2 and interleukin-15—Neoleukin-2/15 (Neo-2/15)—both for trans-activating immune cells surrounding targeted tumor cells and for cis-activating directly targeted immune cells. In trans-activation mode, tumor antigen targeting of the two components enhanced antitumor activity and attenuated toxicity compared with systemic treatment in syngeneic mouse melanoma models. In cis-activation mode, immune cell targeting of the two components selectively expanded CD8+ T cells in a syngeneic mouse melanoma model and promoted chimeric antigen receptor T cell activation in a lymphoma xenograft model, enhancing antitumor efficacy in both cases. IL-2 cytokine therapy is made safer by splitting a designed mimetic in two for tumor targeting. [ABSTRACT FROM AUTHOR]

Highlights: 4-Terminal inorganic perovskite/organic tandem solar cells were made by using semi-transparent inorganic perovskite solar cells and narrow-bandgap organic solar cells as the sub-cells, yielding a power conversion efficiency of 22.34%, which is the highest efficiency for inorganic perovskite/organic tandem solar cells. Inorganic perovskite solar cells made by drop-coating (self-spreading) gave much higher power conversion efficiency than the cells made by spin-coating, enabling perovskite/organic tandem solar cells with higher efficiency. After fast developing of single-junction perovskite solar cells and organic solar cells in the past 10 years, it is becoming harder and harder to improve their power conversion efficiencies. Tandem solar cells are receiving more and more attention because they have much higher theoretical efficiency than single-junction solar cells. Good device performance has been achieved for perovskite/silicon and perovskite/perovskite tandem solar cells, including 2-terminal and 4-terminal structures. However, very few studies have been done about 4-terminal inorganic perovskite/organic tandem solar cells. In this work, semi-transparent inorganic perovskite solar cells and organic solar cells are used to fabricate 4-terminal inorganic perovskite/organic tandem solar cells, achieving a power conversion efficiency of 21.25% for the tandem cells with spin-coated perovskite layer. By using drop-coating instead of spin-coating to make the inorganic perovskite films, 4-terminal tandem cells with an efficiency of 22.34% are made. The efficiency is higher than the reported 2-terminal and 4-terminal inorganic perovskite/organic tandem solar cells. In addition, equivalent 2-terminal tandem solar cells were fabricated by connecting the sub-cells in series. The stability of organic solar cells under continuous illumination is improved by using semi-transparent perovskite solar cells as filter. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the role of tanshinone IIA (TSO IIA) in astrocytic swelling caused by ischemia–reperfusion-like injury in an in vitro model and the molecular mechanisms underlying this effect. Primary brain astrocytes were cultured under conditions of glucose and oxygen deprivation and reoxygenation (OGD/R). The study explored the effects of TSO IIA treatment on cell swelling and injury and the protein levels of aquaporin 4 (AQP4) in the plasma membrane. It then examined the involvement of the high-mobility group box protein 1 (HMGB1)/receptors for advanced-glycation end products (RAGE)/nuclear factor-kappa B (NF-κB)/interleukin-6 (IL-6) pro-inflammatory axis in TSO IIA-mediated protection. The treatment with TSO IIA alleviated OGD/R-induced astrocytic swelling and the overclustering of AQP4 protein in the plasma membrane. In addition, TSO IIA significantly reduced the overexpression of HMGB1 and the high levels of the NF-κB protein in the nucleus and of the IL-6 protein in the cytoplasm and extracellular media induced by OGD/R. The combination of TSO IIA and recombinant HMGB1 reversed these effects. The inhibition of the RAGE, the receptor of HMGB1, induced results similar to those of TSO IIA. In addition, exogenous IL-6 reversed TSO IIA-mediated effect on AQP4 overclustering and cell swelling. TSO IIA significantly reduced astrocyte swelling after OGD/R injury in vitro, via blocking the activation of the HMGB1/RAGE/NF-κB/IL-6 pro-inflammatory axis and thereby decreasing the expression of AQP4 in the plasma membrane. [ABSTRACT FROM AUTHOR]