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To date, the relationship between inflammatory cytokines and progesterone receptors (PRs) has been little studied, although both mediate the mechanism of parturition in human deciduas. Thus, the aim of study was to investigate the role of an inflammatory cytokine, tumor necrosis factor (TNF)-α, in regulating progesterone withdrawal in decidua at human parturition. TNF-α levels and PR isoforms were compared in intrauterine deciduas from women who were in labor (IL, n = 10) or who were not in labor (NIL, n = 10). Nuclear factor-kappaB (NF-κB) signaling and PR status were analyzed in NIL deciduas after TNF-α stimulation. Immunohistochemistry, western blotting, ELISA and reverse transcription-polymerase chain reaction (RT-PCR) were used to localize and quantitate protein and mRNA expression. TNF-α immunostaining, protein levels, PR-A/PR-B ratio and COX-2 level were significantly higher in IL deciduas (all P < 0.05). NF-κB was activated by TNF-α after 24 h stimulation in a dose-dependent manner, and was significantly inactivated by the NF-κB inhibitor panepoxydone, which was associated with decreased PR-A and COX-2 expression (P < 0.05) in not in labor deciduas. In conclusion, TNF-α may have an important role in regulating progesterone withdrawal in human decidua following labor onset. [ABSTRACT FROM AUTHOR]

The coefficient of thermal expansion and thermal strain response behaviour of SiCp/Cu composites prepared by spark plasma sintering (SPS) and pressureless infiltration were studied. The CTEs decreased with increasing reinforcement content. For a fixed SiC content, pressurelessly infiltrated specimens exhibited lower CTE than the SPS specimens. The CTEs of SPS specimens agreed well with the ROM model while the CTE of pressurelessly infiltrated specimens was close to Kerner's predictions. The strain hysteresis loops were developed during thermal cycling. The residual stress increased with increasing reinforcement content. The SPS specimens experienced large dimensional change due to the weak interfacial bond while the pressurelessly infiltrated specimens showed negligible strain hysteresis. The interfacial condition has a pronounced effect on the strain hysteresis behaviour. The improved interfacial bond was beneficial to the decreasing of the CTE and improving the dimensional stability of the composite. [ABSTRACT FROM AUTHOR]

The article discusses the study which examined the effects of heat transfer and permeability constant in twin-roll strip casting. In the study, a 3D coupling temperature-flow mathematical model was developed to examine the flow and heat transfer in the mushy zone and the entire pool during the casting process. The study also used a Darcy's Law-type of porous media treatment to account for the effect of mushy zone on flow and solidification.

Biodegradable polymer/bioceramic composites scaffold can overcome the limitation of conventional ceramic bone substitutes such as brittleness and difficulty in shaping. To better mimic the mineral component and the microstructure of natural bone, novel nano-hydroxyapatite (NHA)/polymer composite scaffolds with high porosity and well-controlled pore architectures as well as high exposure of the bioactive ceramics to the scaffold surface is developed for efficient bone tissue engineering. In this article, regular and highly interconnected porous poly(lactide-co-glycolide) (PLGA)/NHA scaffolds are fabricated by thermally induced phase separation technique. The effects of solvent composition, polymer concentration, coarsening temperature, and coarsening time as well as NHA content on the micro-morphology, mechanical properties of the PLGA/NHA scaffolds are investigated. The results show that pore size of the PLGA/NHA scaffolds decrease with the increase of PLGA concentration and NHA content. The introduction of NHA greatly increase the mechanical properties and water absorption ability which greatly increase with the increase of NHA content. Mesenchymal stem cells are seeded and cultured in three-dimensional (3D) PLGA/NHA scaffolds to fabricate in vitro tissue engineering bone, which is investigated by adhesion rate, cell morphology, cell numbers, and alkaline phosphatase assay. The results display that the PLGA/NHA scaffolds exhibit significantly higher cell growth, alkaline phosphatase activity than PLGA scaffolds, especially the PLGA/NHA scaffolds with 10wt.% NHA. The results suggest that the newly developed PLGA/NHA composite scaffolds may serve as an excellent 3D substrate for cell attachment and migration in bone tissue engineering. [ABSTRACT FROM AUTHOR]

SiCp/Cu composites with high reinforcement content (56–65 vol.-%) were fabricated by spontaneously infiltrating copper alloy into porous SiC preform obtained by powder injection moulding. The main influencing factors of the preparation of the preform and the infiltration behaviour of various preforms were studied. The results indicate that the viscosity increases with an increase in powder loading or decreases with an increase in particle size. The feedstocks with bimodal mixture exhibit low viscosity due to the improvement in packing efficiency. When small particles or bimodal mixture with large size ratio were used, the preforms were difficult to be fully infiltrated. The preforms debound in air exhibit lower infiltration rate than the ones debound in vacuum due to the reduction of porosity and the poor wettability between the oxidised layer and copper alloy. Kinetic analysis on the infiltration curves yielded activation energies of 253 kJ mol–1. [ABSTRACT FROM AUTHOR]

We report on magnetic and magnetotransport properties of single-crystalline Co2 MnSi films grown by using conventional pulsed laser deposition (PLD) method on moderately heated semiconductor GaAs(001) substrates. The films exhibit the expected high Curie temperature and a strong in-plane uniaxial magnetic anisotropy with the easy axis of magnetization along the [1-10] direction. A saturation magnetization of 950 emu/cm³ was measured at 5 K. The temperature dependence of the resistivity shows metallic behavior down to low temperatures. At 5 K, a rather large negative magnetoresistance (MR) of 1.26% has also been observed. [ABSTRACT FROM AUTHOR]

Although the study of X-ray binaries has led to major breakthroughs in high-energy astrophysics, their circumbinary environment at scales of ∼100–10,000 au has not been thoroughly investigated. In this paper, we undertake a novel and exploratory study by employing direct and high-contrast imaging techniques on a sample of X-ray binaries, using adaptive optics and the vortex coronagraph on Keck/NIRC2. High-contrast imaging opens up the possibility to search for exoplanets, brown dwarfs, circumbinary companion stars, and protoplanetary disks in these extreme systems. Here we present the first near-infrared high-contrast images of 13 high-mass X-ray binaries located within ∼2–3 kpc. The key results of this campaign involve the discovery of several candidate circumbinary companions ranging from substellar (brown dwarf) to stellar masses. By conducting an analysis based on Galactic population models, we discriminate sources that are likely background/foreground stars and isolate those that have a high probability (≳60%–99%) of being gravitationally bound to the X-ray binary. This paper seeks to establish a preliminary catalog for future analyses of proper motion and subsequent observations. With our preliminary results, we calculate the first estimate of the companion frequency and the multiplicity frequency for X-ray binaries: ≈0.6 and 1.8 ± 0.9, respectively, considering only the sources that are most likely bound to the X-ray binary. In addition to extending our comprehension of how brown dwarfs and stars can form and survive in such extreme systems, our study opens a new window to our understanding of the formation of X-ray binaries. [ABSTRACT FROM AUTHOR]

Investigated is the resource allocation problem in OFDMA networks by introducing the sleep mode. In contrast to the existing literature, which mainly focuses on improving network throughput by increasing energy consumption energy efficient resource allocation with sleep mode is considered under which some components of the transmitter can be shut down to save energy. A mix integer programming problem is proposed to minimise energy consumption while satisfying the average data rate requirement. The existence of a unique globally optimal resource allocation solution is demonstrated and an iterative algorithm is developed to obtain it. The simulation result shows that the proposed algorithm can effectively save total energy consumption especially when the network is under low load condition. [ABSTRACT FROM AUTHOR]

Observations and theories reveal that star-forming regions eject their members during the early evolution of the cluster. We present an initial search for stars ejected from the young cluster IC 348 based on an analysis of Gaia EDR3 astrometry of previously identified members. We identify six candidate walkaway stars with projected velocities of 5–8 km s−1. The candidate with properties most consistent with a walkaway star, V701 Per, was likely ejected from a small group to the west of IC 348. Three candidates are currently located or have proper motions that trace back to the center of IC 348, though their classification as walkaway stars may also be affected by large astrometric errors. Two other candidate walkaway stars were likely born in other subgroups around IC 348 within the Perseus star-forming region. Since our search criteria are restricted to previously identified members of IC 348, we did not identify any stars that were ejected at high velocities and traveled far from the cluster. Our study suggests that ejections have potentially occurred in both the central region of IC 348 and other subgroups in Perseus. Extending the search range will lead to more candidate ejections and constrain the dynamic properties and evolution of IC 348 by comparing with simulations. [ABSTRACT FROM AUTHOR]

BACKGROUND: Global longitudinal strain (GLS) is an accurate and reproducible parameter of left ventricular (LV) systolic function which has shown meaningful prognostic value. Fast, user-friendly, and accurate tools are required for its widespread implementation. We aim to compare a novel web-based tool with two established algorithms for strain analysis and test its reproducibility. METHODS: Thirty echocardiographic datasets with focused LV acquisitions were analyzed using three different semi-automated endocardial GLS algorithms by two readers. Analyses were repeated by one reader for the purpose of intra-observer variability. CAAS Qardia (Pie Medical Imaging) was compared with 2DCPA and AutoLV (TomTec). RESULTS: Mean GLS values were -15.0 ± 3.5% from Qardia, -15.3 ± 4.0% from 2DCPA, and -15.2 ± 3.8% from AutoLV. Mean GLS between Qardia and 2DCPA were not statistically different (p = 0.359), with a bias of -0.3%, limits of agreement (LOA) of 3.7%, and an intraclass correlation coefficient (ICC) of 0.88. Mean GLS between Qardia and AutoLV were not statistically different (p = 0.637), with a bias of -0.2%, LOA of 3.4%, and an ICC of 0.89. The coefficient of variation (CV) for intra-observer variability was 4.4% for Qardia, 8.4% 2DCPA, and 7.7% AutoLV. The CV for inter-observer variability was 4.5%, 8.1%, and 8.0%, respectively. CONCLUSIONS: In echocardiographic datasets of good image quality analyzed at an independent core laboratory using a standardized annotation method, a novel web-based tool for GLS analysis showed consistent results when compared with two algorithms of an established platform. Moreover, inter- and intra-observer reproducibility results were excellent. [ABSTRACT FROM AUTHOR]

Abstract: A new facility had been set up to test the low temperature properties of the short sample of the small-size cable-in-conduit conductor (CICC). The facility consisted of the background magnet which could provide 7T centric magnetic field, a 50kA superconducting transformer which provided sample current, a 500W/4.5K helium refrigerator which produced both the liquid helium (LHe) and supercritical helium (SHe). An ITER CC conductor short sample was prepared and measured in this testing system. T cs of 7.02K (@4.1T, 10kA) and I c of 8.9kA (@4.1T, 7.06K) were measured. [Copyright &y& Elsevier]

Despite the clinical success of tamoxifen, its resistance remains a major challenge in breast cancer. Here we show that Aurora-A determines tamoxifen sensitivity by regulation of oestrogen receptor (ER)α. Ectopic expression of Aurora-A decreases and depletion of Aurora-A enhances tamoxifen sensitivity in ERα-positive breast cancer. Elevated Aurora-A was significantly associated with the recurrence of ERα-positive tumours. Notably, Aurora-A inhibitor MLN8237, which is currently in clinical trial, synergizes with tamoxifen and overcomes tamoxifen resistance. Furthermore, Aurora-A interacts with and phosphorylates ERα on serine-167 and -305, leading to increase in ERα DNA-binding and transcriptional activity. Elevated levels of Aurora-A are significantly associated with disease-free survival in ERα-positive but not ERα-negative breast cancers. These data suggest that Aurora-A has a pivotal role in tamoxifen resistance and ERα is a bona fide substrate of Aurora-A. Thus, Aurora-A represents a prognostic marker in ERα-positive tumour and a critical therapeutic target in tamoxifen-resistant breast cancer, and Aurora-A inhibitor could be used as either an independent or concurrent agent in tamoxifen-resistant tumour. [ABSTRACT FROM AUTHOR]