We propose a multi-phase, multi-resolution SPH method for fluid/solid interaction with multi-GPU implementation and dynamic load balancing following the movement of the refinement regions. The ...primary design goal of this framework is to maintain the efficiency of the single-resolution SPH model running on a single GPU. To this end, a multi-background mesh is introduced, and the domain is regarded as a nested multi-domain with different resolutions. Validation using both a δ-SPH and Riemann SPH model is shown, and applications to the simulation of the water entry of a projectile with a high Froude number are considered, with comparisons to experimental data from three challenging test cases, showing the proposed model's ability to correctly reproduce the free surface evolution on water entry, the motion of the projectile, and the formation and evolution of multiple cavities depending on entry angle and velocity. An analysis of the computational performance and resolutions achieved (up to 120 million particles) is also provided across several test cases.
•A multi-GPU, multi-node implementation is developed using CUDA for the GPU execution.•The efficiencies of the multi-GPU and multi-resolution model are presented and validated.•The two-phase flow of three water entry cases of slender body is simulated using the model.•The SPH model can provide a sharp interface between the air and water for water entry problems.
Most patients with breast cancer in advanced stages of the disease suffer from bone metastases which lead to fractures and nerve compression syndromes. microRNA dysregulation is an important event in ...the metastases of breast cancer to bone. microRNA-124 (miR-124) has been proved to inhibit cancer progression, whereas its effect on bone metastases of breast cancer has not been reported. Therefore, this study aimed to investigate the role and underlying mechanism of miR-124 in bone metastases of breast cancer.
In situ hybridization (ISH) was used to detect the expression of miR-124 in breast cancer tissues and bone metastatic tissues. Ventricle injection model was constructed to explore the effect of miR-124 on bone metastasis in vivo. The function of cancer cell derived miR-124 in the differentiation of osteoclast progenitor cells was verified in vitro. Dual-luciferase reporter assay was conducted to confirm Interleukin-11 (IL-11) as a miR-124 target. The involvement of miR-124/IL-11 in the prognosis of breast cancer patients with bone metastasis was determined by Kaplan-Meier analysis.
Herein, we found that miR-124 was significantly reduced in metastatic bone tissues from breast cancers. Down-regulation of miR-124 was associated with aggressive clinical characteristics and shorter bone metastasis-free survival and overall survival. Restoration of miR-124 suppressed, while inhibition of miR-124 promoted the bone metastasis of breast cancer cells in vivo. At the cellular level, gain of function and loss-of function assays indicated that cancer cell-derived miR-124 inhibited the survival and differentiation of osteoclast progenitor cells. At the molecular level, we demonstrated that IL-11 partially mediated osteoclastogenesis suppression by miR-124 using in vitro and in vivo assays. Furthermore, IL-11 levels were inversely correlated with miR-124, and up-regulation IL-11 in bone metastases was associated with a poor prognosis.
Thus, the identification of a dysregulated miR-124/IL-11 axis helps elucidate mechanisms of breast cancer metastases to bone, uncovers new prognostic markers, and facilitates the development of novel therapeutic targets to treat and even prevent bone metastases of breast cancer.
Growing attention given to non-toxic solvents for membrane preparation has been the motivation for membrane scientists to develop future generation membranes due to increasing concerns for ...environmental impacts and strict rules. In this study, a novel preparation approach for polypropylene (PP) membranes via TIPS using non-toxic binary diluents consisting of carnauba wax as latent solvent and soybean oil as good solvent was developed successfully. Water and ethanol were used as a quenching bath and extractant of diluents in the membrane, respectively. Impacts of both polymer weight fraction and carnauba wax weight fraction on the phase diagram (phase separation behaviors) of the PP/binary diluents system were investigated firstly. The liquid-liquid (L-L) phase separation region can be enlarged with the continuously increasing of carnauba wax. The effect of adding the second latent diluent on the structures and properties of PP membranes was also studied. The morphology of membranes was further controlled by adjusting the composition of binary diluents. The inter-connected spongelike structure was achieved successfully, which greatly increased the membrane elongation at break. Moreover, vacuum membrane distillation (VMD) desalination experiments showed that the PP membranes produced have the potentiality in VMD desalination application. The carnauba wax after extraction by boiling ethanol could be easily crystallized, separated and recycled by cooling.
•Carnauba wax and soybean oil as binary diluents to prepare PP membrane via TIPS.•Addition of carnauba wax changed interactions in polymer-binary diluents systems.•PP membranes with inter-connected spongelike structures are formed.•A balance between membrane mechanical properties and VMD flux is optimized.•An environment-friendly approach facilitates to recycle diluents efficiently.
Gut tryptophan (Trp) metabolites are produced by microbiota and/or host metabolism. Some of them have been proven to promote or inhibit colorectal cancer (CRC)
and animal models. We hypothesized that ...there is an alteration of gut Trp metabolism mediated by microbiota and that it might be involved in the pathogenesis of cancer in patients with CRC.
To investigate the features of Trp metabolism in CRC and the correlation between fecal Trp metabolites and gut microbiota.
Seventy-nine patients with colorectal neoplastic lesions (33 with colon adenoma and 46 with sporadic CRC) and 38 healthy controls (HCs) meeting the inclusion and exclusion criteria were included in the study. Their demographic and clinical features were collected. Fecal Trp, kynurenine (KYN), and indoles (metabolites of Trp metabolized by gut microbiota) were examined by ultraperformance liquid chromatography coupled to tandem mass spectrometry. Gut barrier marker and indoleamine 2,3-dioxygenase 1 (
) mRNA were analyzed by quantitative real-time polymerase chain reaction. Zonula occludens-1 (ZO-1) protein expression was analyzed by immunohistochemistry. The gut microbiota was detected by 16S ribosomal RNA gene sequencing. Correlations between fecal metabolites and other parameters were examined in all patients.
The absolute concentration of KYN 1.51 (0.70, 3.46) nmol/g
0.81 (0.64, 1.57) nmol/g,
= 0.036 and the ratio of KYN to Trp 7.39 (4.12, 11.72) × 10
5.23 (1.86, 7.99) × 10
,
= 0.032 were increased in the feces of patients with CRC compared to HCs, while the indoles to Trp ratio was decreased 1.34 (0.70, 2.63)
2.46 (1.25, 4.10),
= 0.029. The relative
mRNA levels in patients with CRC (0.27 ± 0.24) were significantly lower than those in HCs (1.00 ± 0.31) (
< 0.001), and the relative
mRNA levels in patients with CRC 1.65 (0.47-2.46) were increased (
= 0.035).
mRNA levels were positively associated with the KYN/Trp ratio (
= 0.327,
= 0.003). ZO-1 mRNA and protein levels were positively correlated with the indoles/Trp ratio (
= 0.035 and
= 0.009, respectively). In addition, the genera
(Actinobacteria) and
(Bacteroidetes)
and members of the phylum Firmicutes (
and
) decreased in CRC and exhibited a positive correlation with indoles in all subjects.
Alteration of fecal Trp metabolism mediated by microbiota is associated with intestinal barrier function and tissue Trp metabolism, and may be involved in the pathogenesis of CRC.
Abstract Challenges in the mechanistic and kinetic study on the polymerization with multiple functional monomers hinder the scale‐up for the controllable reaction process. Herein, poly (isosorbide ...carbonate) synthesized from isosorbide (ISB) was employed to investigate the reaction behavior of functional monomers during polymerization. DFT calculations not only determined the energetically preferable pathways but also provided explanations for the significant differences between terminal groups at the molecular level. Subsequently, the characteristic absorption bands were detected from 1000 to 1100 cm −1 for hydroxyls on ISB, providing a quantitative measure for asymmetric hydroxyls. The reaction network indicated that the reactivity was dominated by the types of terminal groups instead of the chain length. Thereafter, a functional group model with six kinetic parameters was built, acting a crucial role in reaction control and reactor design. This method can be promoted to other functional monomers, conducing to the industrialization of high‐performance polymers.
STUDY DESIGN.Experimental study.
OBJECTIVE.To examine the role of endothelin-1 (ET-1) and the Notch signaling pathway in giant cell tumor (GCT) of the spine.
SUMMARY OF BACKGROUND DATA.Previously ...published studies have shown that the Notch signaling pathway has a role in tumor invasion and that ET-1 is involved in tumor invasion and angiogenesis. However, the roles of both Notch signaling and ET-1 in GCT of the spine remain unknown.
METHODS.Expression of ET-1 in tissue samples from patients with spinal GCT, and adjacent normal tissue, were analyzed by immunohistochemistry and western blot. GCT stromal cells (GCTSCs) were isolated and ET-1 expression was demonstrated by immunofluorescence. Cell viability and cell migration of GCTSCs and human vascular endothelial cells following ET-1 treatment were assessed using the cell counting kit-8 assay and a transwell assay. Receptor activator of nuclear factor kappa-B ligand (RANKL) and osteoprotegerin (OPG) mRNA expression was determined following ET-1 treatment of GCTSCs using quantitative real-time polymerase chain reaction. In GCTSCs treated with ET-1 and the ET-1 signaling antagonist, BQ-123, levels of cyclin D1, vascular endothelial growth factor, matrix metalloproteinase-2 and -9 (MMP-2 and MMP-9), Jagged1, Hes1, Hey2, and Notch intracellular domain were examined by western blot.
RESULTS.Compared with normal adjacent tissue, ET-1 was highly expressed in GCT tissue. In GCTSCs studied in vitro, treatment with ET-1 significantly increased GCTSC and human vascular endothelial cells growth and migration and increased the expression of RANKL and OPG, meanwhile the ratio of RANKL/OPG was increased, in GCTSCs, it upregulated the production of cyclin D1, vascular endothelial growth factor, MMP-2, MMP-9, Jagged1, Hes1, Hey2, and Notch intracellular domain expression in a dose-dependent manner. Treatment with BQ-123 reversed these effects.
CONCLUSION.In GCT of the spine, ET-1 showed increased expression. In cultured GCTSCs, ET-1 treatment activated the Notch signaling pathway.Level of Evidence2
In this review article, we first briefly introduce the transport theory and quantum molecular dynamics model applied in the study of the heavy ion collisions from low to intermediate energies. The ...developments of improved quantum molecular dynamics model (ImQMD) and ultra-relativistic quantum molecular dynamics model (UrQMD), are reviewed. The reaction mechanism and phenomena related to the fusion, multinucleon transfer, fragmentation, collective flow and particle production are reviewed and discussed within the framework of the two models. The constraints on the isospin asymmetric nuclear equation of state and in-medium nucleon-nucleon cross sections by comparing the heavy ion collision data with transport models calculations in last decades are also discussed, and the uncertainties of these constraints are analyzed as well. Finally, we discuss the future direction of the development of the transport models for improving the understanding of the reaction mechanism, the descriptions of various observables, the constraint on the nuclear equation of state, as well as for the constraint on in-medium nucleon-nucleon cross sections.
The parameter mismatch caused by the parameter uncertainties and unknown disturbances degrades the performance of finite-control-set model predictive control (FCS-MPC). This paper presents a ...model-free fault-tolerant predictive control (MFFTPC) method based on an extended sliding mode observer (ESMO) for the surface-mounted permanent magnet synchronous motor (SPMSM) drive system. First, considering parameter uncertainties and unknown disturbances, a novel ultra-local model (ULM) is established for the PMSM drive system. Next, a finite-control-set model-free fault-tolerant predictive current controller (FCS-MFFTPCC) is designed in the current loop, and the model-free deadbeat fault-tolerant predictive speed controller (MFDFTPSC) is designed in the speed loop. Then, unknown parts of the novel ULM are estimated by the designed ESMO and compensated for the errors caused by the parameter mismatches. Thus, the presented method reduces the dependence on the precise model and eliminates the effect caused by parameter mismatches on the MPC control performance of the SPMSM drive system.
ABSTRACT
The catalyzed and uncatalyzed reaction mechanisms of the melt transesterification process of bisphenol‐A and diphenyl carbonate are proposed based on nucleophilic substitution at the ...carbonyl group of the reactants. The reaction paths and energy barriers of the melt transesterification reaction were predicted and identified via density functional theory (DFT) calculations. The calculations reveal that the different oligomers with only one repeating unit are formed through different thermal processes. The theoretical evaluation further indicates that the basic hydroxide catalysts can reduce the energy barrier for the transesterification reaction, which allows subsequent nucleophilic attack to easily occur. Furthermore, the reaction kinetics of transesterification using tetraethyl ammonium hydroxide as a catalyst were investigated experimentally over a temperature range of 155–175°C. The reaction rate constants and equilibrium constants were determined based on the functional group model, and the equilibrium constants decreased with increasing reaction temperature. A detailed molecular species model with a specific repeating unit (n = 3) was developed and applied to predict the change in the reactants, oligomers, and phenol, and the experimental data and model calculation agree quite well. The standard curves of the oligomer were reversely derived, which provide intuitive insight into the concentration change of each oligomer. Both the DFT calculations and experimental results indicate that the C1 oligomer is first formed, and some of which are then converted to other types or higher molecular weight oligomers.
Geodynamic mechanism responsible for the generation of Silurian granitoids and the tectonic evolution of the Qilian orogenic belt remains controversial. In this study, we report the results of zircon ...U–Pb age, and systematic whole-rock geochemical data for the Haoquangou and Liujiaxia granitoids within the North Qilian orogenic belt and the Qilian Block, respectively, to constrain their petrogenesis, and the Silurian tectonic evolution of the Qilian orogenic belt. Zircon U–Pb ages indicate that the Haoquangou and Liujiaxia intrusions were emplaced at 423 ± 3 Ma and 432 ± 4 Ma, respectively. The Haoquangou granodiorites are calc-alkaline, while the Liujiaxia granites belong to the high-K calc-alkaline series. Both are peraluminous in composition and have relatively depleted Nd isotopic ε
Nd
(t) = (− 3.9 – + 0.6) characteristics compared with regional basement rocks, implying their derivation from a juvenile lower crust. They show adakitic geochemical characteristics and were generated by partial melting of thickened lower continental crust. Post-collisional extensional regime related to lithospheric delamination was the most likely geodynamic mechanism for the generation of the Haoquangou granodiorite, while the Liujiaxia granites were generated in a compressive setting during continental collision between the Qaidam and Qilian blocks.
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