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The dynamic viscoelastic behavior and phase morphology of high impact polystyrene (HIPS)/high density polyethylene (HDPE) blends were investigated by dynamic rheological test and scanning electron microscopy (SEM). The compatibilizing effect of 1%(mass fraction, same as below) micron-CaCO3 and nano-CaCO3 on HIPS/HDPE(30/70) immiscible blend was compared. The results indicate that the complex viscosity and storage modulus of HIPS/HDPE blends at low frequencies show positive deviation from the mixing rule when HDPE is less than 30%, while negative deviation is observed when HDPE is more than 30%. The former is related to the interaction between HDPE and PB particles and the latter is attributed to the poor interfacial interaction between HDPE matrix and PS particles. When HIPS is the matrix phase, HDPE particles display broad size distribution. When HDPE acts as a matrix phase, PS dispersed phase exhibits bimodal size distribution corresponding to the presence of two different types of PS dispersed particles. 1% nano-CaCO3 has a certain compatibilizing effect on HIPS/HDPE(30/70) immiscible blend, which is mainly located at HIPS/HDPE interface and in the HDPE matrix, while micron-CaCO3 acts as viscosifier rather than compatibilizer, which is confined in the HDPE matrix.

To evaluate the settlement of saturated clay ground under the time-dependent loading, the unified hardening (UH) constitutive model considering the time effect was used to describe the elastic visco-plasticity of the soil and Hansbo's flow equation was applied to reflect non-Darcian flow. Thus, the classical Terzaghi consolidation equation was modified considering the influence of gravitational stress of the ground. The finite volume method was introduced to solve the numerical solution of the modified equation, and the corresponding program was compiled based on the above algorithm. The applicability of the present program was validated by comparing with the existing results in the literature. Then the effect of some parameters on the consolidation behaviour was investigated. The calculated results showed that the excess pore water pressure in the ground is accumulated at the initial stage of loading. Furthermore, when the viscosity of the soil is considered, the maximum excess pore water pressure in the ground away from the permeable boundary can even exceed the load imposed on the upper surface of the ground. In addition, prolonging the construction period, thickening the soil layer, increasing the secondary consolidation coefficient and the parameters of Hansbo's flow will delay the consolidation process of ground. [ABSTRACT FROM AUTHOR]

Timing of the collision between India and Eurasian plate is still debated. In this paper, zircon U-Pb geochronology, whole rock geochemistry and zircon Hf isotope analysis have been carried out for the Tuolong intrusion exposed in the middle of Linzhou County, Tibet, in order to further constrain the collision time of the India- Eurasian plate. The quartz monzonite porphyry outcropped in Tuolong pluton intruded into the Pana Formation as stock. Zircon U-Pb dating results show that the quartz monzonite porphyry was formed in Eocene (50. 5±0. 6 Ma) with εHf (f) value of -0.6 to - 0.5. Quartz monzonite porphyries display metaluminous and shoshonitic characteristics with low A/CNK and high K2O/Na2O value and high K20 contents. They are generally depleted in high field strength elements (Nb, Ta, Ti and P) and enriched in large ion lithophile elements (Th, U and Pb). Chondrite-normalized REE patterns are characterized by high (La/Yb)N values (15.3 ~ 16.3) with weak negative Eu anoma-lies (0.56~0.69), the differentiation of light and heavy rare earth elements is obvious. The low A/CNK value, the negative correlation between P2O5 and SiO2, and the positive correlation between Y content and Rb content indicate that the quartz monzonite porphyry is I-type granite. Combined with results of previous studies, it is considered that the Tuolong quartz monzonite porphyry may be the product of partial melting of the relatively ancient metamorphic intermediate-basic rock, and was formed as the consequences of subduction and break-off caused by the India- Eurasian plate collision, indicating that the India-Asia continent collision should have occurred before 50 Ma. [ABSTRACT FROM AUTHOR]

Background: Evidence shows that the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway participates in the pathogenesis of neuropathic pain. Our previous study revealed that electroacupuncture (EA) attenuated neuropathic pain via activation of alpha-7 nicotinic acetylcholine receptor (α7nAChR) in the spinal cord. However, whether 2 Hz EA alleviates neuropathic pain by regulating the downstream molecules JAK2/STAT3 has not been fully clarified. Methods: Paw withdrawal threshold (PWT) was used as a marker of mechanical allodynia in rats with spared nerve injury (SNI). After applying 2 Hz EA on day 3, 7, 14 and 21 post-surgery, spinal expression of JAK2, STAT3 and pro-inflammatory cytokine interleukin (IL)-6 was examined using quantitative reverse transcription and real-time polymerase chain reaction (qRT-PCR) and Western blot analysis. Intrathecal injection of the α7nAChR antagonist alpha-bungarotoxin (α-Bgtx) was used to further explore the mechanism underlying the effects of 2 Hz EA on expression of JAK2/STAT3 in SNI rats. Results: It was found that levels of spinal STAT3 and IL-6 mRNA, as well as levels of phosphorylated (p)-JAK2, p-STAT3 and IL-6 protein, were markedly increased in SNI rats. 2 Hz EA attenuated the SNI-induced up-regulation of p-JAK2, p-STAT3 and IL-6 expression in the spinal cord. Furthermore, intrathecal injection of α-Bgtx (1.0 μg/kg) not only inhibited the effect of 2 Hz EA on mechanical hypersensitivity but also ameliorated the down-regulation of p-JAK2, p-STAT3 and IL-6 expression induced by 2 Hz EA. Conclusion: This study revealed that 2 Hz EA attenuated SNI-induced mechanical hypersensitivity and the concomitant up-regulation of spinal JAK2, STAT3 and IL-6 in SNI rats, suggesting that suppression of the JAK2/STAT3 signaling pathway might be the mechanism underlying the therapeutic effect of 2 Hz EA on neuropathic pain. [ABSTRACT FROM AUTHOR]

Peritoneal fibrosis (PF) is characterized by progressive accumulation of extracellular matrix (ECM) components in the peritoneum under high glucose conditions. Rapamycin has previously been shown to inhibit ECM accumulation of peritoneal mesothelial cells (PMCs) and prevent PF. Here we explored the undefined mechanisms by which rapamycin inhibits ECM accumulation of PMCs. We used high-glucose peritoneal dialysis solution (PDS) in a mouse peritoneal dialysis model to induce in vivo PF and in human PMCs in vitro to stimulate ECM accumulation. The mice that received chronic PDS infusions showed typical features of PF, including markedly increased peritoneal thickness, excessive matrix deposition, increased peritoneal permeability, and higher expressions of α-smooth muscle actin and collagen I. Rapamycin significantly ameliorated these pathological changes. There was a parallel decrease in lipid accumulation in the peritoneum of rapamycin-treated mice. Rapamycin significantly inhibited high-glucose PDS-induced ECM accumulation and reduced the lipid droplet in human PMCs in the presence of PDS. The effects of rapamycin on intracellular lipid metabolism correlated with a series of steps in lipid homeostasis; namely, a decrease in low density lipoprotein receptor-mediated lipid influx, which was mediated through the downregulation of sterol regulatory element-binding protein-2 (SREBP-2) and SREBP cleavage-activating protein (SCAP), and an increase in adenosine triphosphate-binding cassette transporter A1-mediated lipid efflux, which was mediated through the upregulation of the liver X receptor α and peroxisome proliferator-activated receptor α. We conclude that rapamycin shows a clear protective effect on high-glucose PDS-induced PF by improving the disruption of intracellular lipid homeostasis., Competing Interests: None.