The development of Expanded Polystyrene (EPS) concrete involves two major concerns: (a) poor strength resulting in the EPS concrete unsuitable for structural applications, and (b) segregation of the ...ultra-light weight of EPS during mixing (EPS is approximately 100 times lighter than concrete). Though EPS displays high insulation (thermal conductivity ≈ 0.04 W/m-K), these issues limit its usage in concrete. This study aims to develop a lightweight-EPS cement composite (LECC) having enhanced insulating capacity as well as satisfactory compressive strength for structural applications. To mitigate the deteriorating effect of EPS on strength, the LECC is developed using the base material of ultra-high performance concrete (UHPC). EPS beads of 3–5 mm diameter are mixed in UHPC in five proportions by volume of 0, 16, 25, 36, 45% and the resulting composites are tested for mechanical and thermal properties. Microstructural characterization is performed using micro-computed tomography (μCT). The choice of the UHPC ingredients proportion is found successful in achieving a balance between an optimum viscosity and satisfactory workability for uniform dispersion of EPS, confirmed by the flow values and μCT results. McLachlan's general effective media approximation, based on percolation theory, is used to homogenize the composite and estimate its thermal conductivity with satisfactory accuracy. The LECC thus developed displays a strength 45 MPa with a corresponding density of 1677 kg/m3 and thermal conductivity of 0.58 W/m-K.
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The effects of various ions in cement-based solutions on the water retention capacity and ion absorbency of superabsorbent polymers (SAPs) are studied herein. It is verified that the retention ...capacity of the SAP is reduced due to the absorbed Ca2+ from solution, and the SAP releases monovalent cations such as Na+ into the solution upon absorption of Ca2+. Importantly, it was determined that non-multivalent cations in solutions play a critical role in the retention capacity of SAPs. As the total ion concentration (TIC) of the solution increases, the retention capacity improves. Higher TIC yields a weaker osmotic pressure, which reduces the driving force for the initial absorption of SAP. Therefore, the amount of the Ca2+ absorbed in the SAP decreases and the retention capacity improves. Based on the accurately measured ionic characteristics during absorption and desorption, the complicated retention phenomenon and its ionic dependence in cement-based solutions are clearly understood.
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Given environmental friendliness, high‐temperature proton exchange membrane fuel cells (HT‐PEMFCs) can be the alternative power source for clean power generation. However, neither developments nor ...strategies of diffusion media are actively conducted yet to achieve high‐performance HT‐PEMFCs. Herein, a nanoporous carbon nanotube (CNT) sheet, a new anode diffusion layer between the gas diffusion layer|bipolar plate interface that improves fuel cell performance and durability by CNT purification for facilitating fuel accessibility with uniform interfacial contact for reducing acid loss, is reported. Configuration of the optimal CNT‐inserted fuel cell is examined and proposed under the operating temperature of 140–200 °C. The underlying mechanism of this new diffusion layer with multiphysics simulation elucidates that the nanoporous nature induces gas‐wall collision, enabling uniform dispersion within adjacent diffusion media. These fuel cells outperform performance over two times higher and have a voltage decay rate nearly two times lower than conventional HT‐PEMFC.
A purified nanoporous carbon nanotube (CNT) sheet with few impurities is synthesized and inserted between the anode gas diffusion media and bipolar plate. The CNT‐inserted fuel cell notably improves performance and durability. Fuel cell testing combined with multiphysics simulation reveals that optimal nanoporous media increases gas‐wall collision, thereby achieving uniform gas dispersion in the fuel cell.
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•High-volume limestone replacement in ultra-high performance fiber-reinforced concrete (UHPFRC) was proposed.•Range of compressive strength of 150–180 MPa was obtained with cement ...contents of 400–600 kg/m3 at ambient curing condition.•The replacement accelerated initial hydration reaction and mitigated autogenous shrinkage of UHPFRC.•Cement consumption index (CCI) was used to quantitatively evaluate the efficiency of cement consumption.
In spite of superior mechanical performance, ultra-high performance fiber-reinforced concrete (UHPFRC) is one of the most inefficient construction materials in terms of Portland cement usage. In this study, low-cement UHPFRC is proposed using high-volume limestone powder as a binder. Under ambient curing conditions, ultra-high strength (150–180 MPa) at 91 days was achieved with cement amount of 400–600 kg/m3. Efficient cement consumption of the concrete was quantitatively evaluated based on cement consumption index (CCI). In addition, autogenous shrinkages of UHPFRCs were effectively mitigated owing to the filler effect of limestone powder and the cement dilution effect which increases the water-to-cement ratio. Although this type of concrete incorporates quartz powder as physical filler, cement hydration was further accelerated with increasing limestone powder content. Accelerated cement hydration owing to the limestone powder shortens not only the dormant period but also the duration of the early stage during which risk of cracking is exceptionally high because of rapid shrinkage and low mechanical property. The production strategy suggested herein can practically contribute to reducing demand for Portland cement, along with advantages in dimensional stability.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
One of the key features of ultra-high performance fiber-reinforced concrete (UHPFRC) is the inclusion of quartz powder (QP) as a filler to optimize granular packing. However, QP has not been compared ...against limestone powder (LP) in terms of the filler effects, although it can affect hydration characteristics, strength development, and autogenous shrinkage of the concrete. In this study, the effectiveness of LP as a filler is evaluated against that of QP in order to verify its potential for use as a functional and human-friendly filler in UHPFRC. For this purpose, five types of fillers consisting of similar-sized QP and LP were designed while maintaining the same water-to-cement (w/c) and superplasticizer-to-cement (sppl/c) ratios. The early age strength increased by up to 12% depending on the LP content, due to the filler effect which accelerates cement hydration by providing a preferential surface for nucleation. Although the 28-day strength was 4%–7% lower than that of the classical UHPFRC containing QP, the 91-day strength was 1%–4% higher. The early age shrinkage was also accelerated by the filler effect of the LP, but its duration was shortened in proportion to the LP content.
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DNA damage‐induced apoptosis suppressor (DDIAS) facilitates the survival of lung cancer by suppressing apoptosis. Moreover, DDIAS promotes tyrosine phosphorylation of signal transducer and activator ...of transcription 3 (STAT3) via their interaction. Here, we identified miconazole as an inhibitor of DDIAS/STAT3 interaction by screening a chemical library using a yeast two‐hybrid assay. Miconazole inhibited growth, migration and invasion of lung cancer cells. Furthermore, miconazole suppressed STAT3 tyrosine Y705 phosphorylation and the expression of its target genes, such as cyclin D1, survivin and snail but had no suppressive effect on the activation of ERK1/2 or AKT, which is involved in the survival of lung cancer. As expected, no interaction between DDIAS and STAT3 occurred in the presence of miconazole, as confirmed by immunoprecipitation assays. Mouse xenograft experiments showed that miconazole significantly suppressed both tumor size and weight in an NCI‐H1703 mouse model. Tyrosine phosphorylation of STAT3 at Y705 and expression of its targets, such as cyclin D1, survivin and snail, were decreased in miconazole‐treated tumor tissues, as compared with those in vehicle‐treated tumor tissues. These data suggest that miconazole exerts an anti–cancer effect by suppressing STAT3 activation through inhibiting DDIAS/STAT3 binding.
DNA damage‐induced apoptosis suppressor promotes activation of tyrosine phosphorylation of STAT3 through their interaction. Miconazole exerts an anti–cancer effect by suppressing STAT3 activation through inhibition of DDIAS/STAT3 binding.
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Human microbiota refers to living microorganisms which colonize our body and crucially contribute to the metabolism of nutrients and various physiologic functions. According to recently accumulated ...evidence, human microbiota dysbiosis in the genital tract or pelvic cavity could be involved in the pathogenesis and/or pathophysiology of endometriosis. We aimed to investigate whether the composition of microbiome is altered in the peritoneal fluid in women with endometriosis. We recruited 45 women with histological evidence of ovarian endometrioma and 45 surgical controls without endometriosis. Following the isolation of extracellular vesicles from peritoneal fluid samples from women with and without endometriosis, bacterial genomic DNA was sequenced using next-generation sequencing of the 16S rDNA V3-V4 regions. Diversity analysis showed significant differences in the microbial community at phylum, class, order, family, and genus levels between the two groups. The abundance of
,
,
, and
significantly increased while the abundance of
,
, and
significantly decreased in the endometriosis group compared with those in the control group (
< 0.05). These findings strongly suggest that microbiome composition is altered in the peritoneal environment in women with endometriosis. Further studies are necessary to verify whether dysbiosis itself can cause establishment and/or progression of endometriosis.
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In the CLASSIC and MAGIC trials, microsatellite instability (MSI)-high status was a favorable prognostic and potential negative predictive factor for neoadjuvant/adjuvant chemotherapy in resectable ...gastric cancer (GC). Given the low prevalence of MSI-high status in GC and its association with other positive prognostic variables, large data sets are needed to draw robust evidence of its prognostic/predictive value.
We performed a multinational, individual-patient-data meta-analysis of the prognostic/predictive role of MSI in patients with resectable GC enrolled in the MAGIC, CLASSIC, ARTIST, and ITACA-S trials. Prognostic analyses used multivariable Cox models (MVM). The predictive role of MSI was assessed both in an all-comer population and in MAGIC and CLASSIC trials by MVM testing of the interaction of treatment (chemotherapy plus surgery
surgery) with MSI.
MSI status was available for 1,556 patients: 121 (7.8%) had MSI-high status; 576 were European, and 980 were Asian. In MSI-high versus MSI-low/microsatellite stable (MSS) comparisons, the 5-year disease-free survival (DFS) was 71.8% (95% CI, 63.8% to 80.7%) versus 52.3% (95% CI, 49.7% to 55.1%); the 5-year overall survival (OS) was 77.5% (95% CI, 70.0% to 85.8%) versus 59.3% (95% CI, 56.6% to 62.1%). In MVM, MSI was associated with longer DFS (hazard ratio HR, 1.88; 95% CI, 1.28 to 2.76;
< .001) and OS (HR, 1.78; 95% CI, 1.17 to 2.73;
= .008), as were pT, pN, ethnicity, and treatment. Patients with MSI-low/MSS GC benefitted from chemotherapy plus surgery: the 5-year DFS compared with surgery only was 57% versus 41% (HR, 0.65; 95% CI, 0.53 to 0.79), and the 5-year OS was 62% versus 53% (HR, 0.75; 95% CI, 0.60 to 0.94). Conversely, those with MSI-high GC did not: the 5-year DFS was 70% versus 77% (HR, 1.27; 95% CI, 0.53 to 3.04), and the 5-year OS was 75% versus 83% (HR, 1.50; 95% CI, 0.55 to 4.12).
In patients with resectable primary GC, MSI is a robust prognostic marker that should be adopted as a stratification factor by clinical trials. Chemotherapy omission and/or immune checkpoint blockade should be investigated prospectively in MSI-high GCs according to clinically and pathologically defined risk of relapse.
The Cancer Genome Atlas (TCGA) project recently uncovered four molecular subtypes of gastric cancer: Epstein-Barr virus (EBV), microsatellite instability (MSI), genomically stable (GS), and ...chromosomal instability (CIN). However, their clinical significances are currently unknown. We aimed to investigate the relationship between subtypes and prognosis of patients with gastric cancer.
Gene expression data from a TCGA cohort (
= 262) were used to develop a subtype prediction model, and the association of each subtype with survival and benefit from adjuvant chemotherapy was tested in 2 other cohorts (
= 267 and 432). An integrated risk assessment model (TCGA risk score) was also developed.
EBV subtype was associated with the best prognosis, and GS subtype was associated with the worst prognosis. Patients with MSI and CIN subtypes had poorer overall survival than those with EBV subtype but better overall survival than those with GS subtype (
= 0.004 and 0.03 in two cohorts, respectively). In multivariate Cox regression analyses, TCGA risk score was an independent prognostic factor HR, 1.5; 95% confidence interval (CI), 1.2-1.9;
= 0.001. Patients with the CIN subtype experienced the greatest benefit from adjuvant chemotherapy (HR, 0.39; 95% CI, 0.16-0.94;
= 0.03) and those with the GS subtype had the least benefit from adjuvant chemotherapy (HR, 0.83; 95% CI, 0.36-1.89;
= 0.65).
Our prediction model successfully stratified patients by survival and adjuvant chemotherapy outcomes. Further development of the prediction model is warranted.
For optimum production of ultra-high performance concrete (UHPC), the material and microstructural properties of UHPC cured under various heat treatment (HT) conditions are studied. The effects of HT ...temperature and duration on the hydration reaction, microstructure, and mechanical properties of UHPC are investigated. Increasing HT temperature accelerates both cement hydration and pozzolanic reaction, but the latter is more significantly affected. This accelerated pozzolanic reaction in UHPC clearly enhances compressive strength. However, strength after the HT becomes stable as most of the hydration finishes during the HT period. Particularly, it was concluded that the mechanical benefit of the increased temperature and duration on the 28 day-strength is not noticeable when the HT temperature is above 60 °C (with a 48 h duration) or the HT duration is longer than 12 h (with 90 °C temperature). On the other hand, even with a minimal HT condition such as 1 day at 60 °C or 12 h at 90 °C, outstanding compressive strength of 179 MPa and flexural tensile strength of 49 MPa are achieved at 28 days. Microstructural investigation conducted herein suggests that portlandite content can be a good indicator for the mechanical performance of UHPC regardless of its HT curing conditions. These findings can contribute to reducing manufacturing energy consumption, cost, and environmental impact in the production of UHPC and be helpful for practitioners to better understand the effect of HT on UHPC and optimize its production.
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