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Flow and shock train development in a hypersonic inlet isolator at various wall surface temperatures, Tw, and freestream static temperatures, T8, were studied through numerical simulations. A non-dimensional parameter, Tw/T8, is used to characterize flow behaviors in hypersonic isolator. With the increase of Tw/T8, boundary-layer thickness increases and boundary-layer momentum thickness decreases at the entrance of isolator. Inside the isolator without the presence of backpressure, skin friction decreases with the increase of Tw/T8. The main cause is a lower velocity gradient near the wall at high temperature. A lower skin friction on high wall temperature results in a stronger separation with shock impingement. Under backpressure conditions, with the increase of Tw/T8, an upstream movement of the starting position of the shock train inside the isolator, an increase in the length of the shock train, and an increase in pressure coefficient on the wall surface are observed. [ABSTRACT FROM AUTHOR]

Numerical studies of suspended-floor structures were conducted, and viscous dampers were applied to improve their seismic performances. The following issues were analyzed under 20 earthquake records: seismic responses of the primary structure and suspended floors, the distributions of the damping coefficient c0, and the interstory stiffness of the suspended floors. There was a significant reduction in the roof drift and the base shear force of the cores after replacing the steel bars with viscous dampers. The suspended-floor structures with viscous dampers exhibited an optimal c0. The suspended-floor structure with a triangular distribution of c0 showed a smaller seismic response than the one with a uniform distribution of c0. Under the design-based earthquake, there was complete damage of nonstructural components in the y-direction. Hence, applications of diagonal steel braces within the 1st to 10th floors were suggested to increase the lateral stiffness of the suspended floors in the y-direction. The application of diagonal steel braces reduced the story drift Sd of the suspended floors, resulting in slight damage to nonstructural components under the design basis earthquake (DBE) hazard level. However, the roof floor, which contains electrical and mechanical components, exhibited an increase in Sd after the application of the diagonal steel braces. With increasing stiffness of the diagonal brace, the story drift profile of the suspended floors tended to be uniform, and the suspendedfloor structures with the uniform distribution of c0 exhibited seismic performances closer to those of the suspended-floor structures with the triangular distribution of c0. [ABSTRACT FROM AUTHOR]

Tumor invasion and metastasis are complex interfacial mechanical processes between the tumor and its surrounding tissue, with the interfacial curvature of tumor playing an important role in cancer progression. In this study, the potential role of interfacial curvature in the prognosis of patients with colon adenocarcinoma is investigated. The front edge interfacial curvature of adenocarcinoma from biopsies of patients in different tumor, lymph node, and metastasis (TNM) stages are calculated and compared, and prognosis assessment is conducted using Kaplan-Meier and Cox proportional hazards regression analyses. Results reveal that patients with larger interfacial curvature of adenocarcinoma are more likely to belong to higher TNM stages. Concomitantly, in the same TNM stage, patients with increased adenocarcinoma interfacial curvature show worse prognosis with higher recurrence and lower survival rates. Besides, interfacial curvature is an independent prognostic factor for cause-specific survival and relapse-free survival among all selected patients. Mechanical models of colon adenocarcinoma invasion and metastasis are established to better understand the close association between interfacial curvature and tumor progression. The results together with hematoxylin and eosin staining indicate that metastasis in stages T3N0M0 and T3N1M0 may be linked to large interfacial curvatures. Therefore, interfacial curvature may serve as a potential index for predicting prognosis in patients with colon adenocarcinoma. [ABSTRACT FROM AUTHOR]

Background: Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) are a novel and promising strategy for tissue engineering because of their ability to differentiate into many cell types. We characterized the differentiation of WJ-MSCs into endometrial epithelial cell (EEC)-like and endometrial stromal cell (ESC)-like cells and assessed the effect of 17ß-estradiol and 8-Br-cAMP on the differentiation system. Methods: WJ-MSCs were treated in two ways to differentiate into EEC-like and ESC-like cells respectively: cocultured with ESCs in control/differentiation medium (17ß-estradiol, growth factors); and cultured in control/differentiation medium (8-Br-cAMP alone or 8-Br-cAMP plus 17ß-estrogen and growth factors). Three signaling pathway inhibitors (SB203580, PD98059, H89) were used to investigate the mechanism of WJ-MSC differentiation into ESC-like cells. Immunofluorescence, western blot and flow cytometry analyses were used to analyze expression of epithelial markers and stromal cell markers. Enzyme-linked immunosorbent assays were used to test the production of secretory proteins associated with the differentiation of ESC-like cells. Results: 17ß-estradiol at 1 µM downregulated vimentin and CD13 and upregulated cytokeratin and CD9 proteins, promoting the differentiation of WJ-MSCs into EEC-like cells in the coculture system. 8-Br-cAMP at 0.5 mM upregulated vimentin and CD13 and downregulated CK and CD9, promoting the differentiation of WJ-MSCs into ESC-like cells. Prolactin (PRL) and insulin-like growth factor-binding protein 1 (IGFBP1) were upregulated and the protein kinase A (PKA) signaling pathway was activated, whereas extracellular signal-regulated (ERK)1/2 and p38 mitogen-activated protein kinase (MAPK) were not affected. Conclusions: 17ß-estradiol at 1 µM is a good inducer for facilitating the differentiation of WJ-MSCs into EEC-like cells. 8-Br-cAMP plus estrogen and growth factors can induce the differentiation of WJ-MSCs into ESC-like cells. During the differentiation of WJ-MSCs into ESC-like cells, PRL and IGFBP1 were upregulated by the treatment and the PKA signaling pathway was activated, whereas ERK1/2 and p38 MAPK were not affected. These findings suggest a promising approach to the treatment of endometrial damage and other endometrial diseases and suggest new applications for WJ-MSCs in clinical practice. [ABSTRACT FROM AUTHOR]

A series of clinical trials have confirmed the correlation between vascular calcification (VC) and cardiovascular events and mortality. However, current treatments have little effects on the regression of VC. Potent and illustrative mechanisms have been proven to exist in both bone metabolism and VC, indicating that these two processes share similarities in onset and progression. Multiple osteoblast-like cells and signaling pathways are involved in the process of VC. In this review, we summarized the roles of different osteoblast-like cells and we emphasized on how they communicated and interacted with each other using different signaling pathways. Further studies are needed to uncover the underlying mechanisms and to provide novel therapies for VC. [ABSTRACT FROM AUTHOR]

In chronic kidney disease (CKD), simultaneous mineral and skeleton changes are prevalent, known as CKD-mineral bone disorder (CKD-MBD). Arterial calcification (AC) is a clinically important complication of CKD-MBD. It can increase arterial stiffness, which leads to severe cardiovascular events. However, current treatments have little effect on regression of AC, as its mechanisms are still unclear. There are multiple risk factors of AC, among which Malnutrition-Inflammation Complex Syndrome (MICS) is a new and crucial one. MICS, a combined syndrome of malnutrition and inflammation, generally begins at the early stage of CKD and becomes obvious in end-stage renal disease (ESRD). It was linked to reverse epidemiology and associated with increased cardiovascular mortality in ESRD patients. Recent data suggest that MICS can trigger CKD-MBD and accelerate the course of AC. In this present review, we summarize the recent understanding about the aggravating effects of MICS on AC and discuss the possible underlying mechanisms. A series of findings indicate that targeting MICS will provide a potential strategy for treating AC in CKD. [ABSTRACT FROM AUTHOR]

In this paper, a fatigue lifetime prediction method of the hyper-static truss structure is established based on the improved failure mode recognition algorithms and GM(1,1) model. In the improved Failure Mode Recognition Algorithms(FMRA), a second-order logarithmic is chosen to assure choice of the Control Ambit Parameter (CAP) in the precision interval and a critical failure internal stress criterion is used to improve the efficiency of FMRA. Subsequently, by comparing the equation formula between the GM(1,1) model and the Weibull three-parameter distribution function, a new parameter estimation method of the Weibull distribution is developed to determine three parameters. The fatigue lifetime with varying levels of reliability is calculated on the basis of the Weibull distribution. Finally, a numerical example of the 10-bar truss structure was used to prove the validity of the fatigue lifetime prediction method. [ABSTRACT FROM AUTHOR]

The eyeless animal C. elegans is able to sense light and engages in phototaxis behavior that is mediated by photoreceptor cells. However, the molecular and cellular mechanisms underlying phototransduction in C. elegans remain largely unclear. By recording the photoreceptor neuron ASJ in wild-type and various mutant worms, we found that phototransduction in ASJ is a G protein–mediated process and requires membrane-associated guanylate cyclases, but not typical phosphodiesterases. In addition, we found that C. elegans phototransduction requires LITE-1, a candidate photoreceptor protein known to be a member of the invertebrate taste receptor family. Our genetic, pharmacological and electrophysiological data suggest a model in which LITE-1 transduces light signals in ASJ via G protein signaling, which leads to upregulation of the second messenger cGMP, followed by opening of cGMP-sensitive CNG channels and stimulation of photoreceptor cells. Our results identify a phototransduction cascade in C. elegans and implicate the function of a 'taste receptor' in phototransduction. [ABSTRACT FROM AUTHOR]