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The self-resonating water jet offers the advantages of both a cavitation jet and a pulsed jet, and thus has been widely used for many practical applications. In the present study, the 120°-impinging edge Helmholtz nozzle was investigated for better erosion performance. The oscillating mechanism was analyzed from both numerical and experimental perspectives. The results showed that the cavitation clouds in the chamber dominate the oscillating frequency. The frequency resulting from the non-linear interaction was also observed in the simulation. The dominant frequency increases linearly as pressure decreases without entrained air. The frequency modulation was achieved through various inspiratory methods, and the modulation range was dependent on the pressure drop. The erosion performance was improved with entrained air, and the improvement was effected by the inspiratory method. The oscillating frequency was determined by the forced frequency of entrained air, and the best erosion performance was achieved at the frequency closest to the fundamental frequency. A feasible method to improve the erosion performance was investigated in this preliminary study, which could provide a guide for practical applications. [ABSTRACT FROM AUTHOR]

Herbal medicines are known to have numerous benefits, including lower toxicity and fewer side effects than traditional chemotherapeutic drugs. In traditional Chinese medicine, the rhizome of Pinellia pedatisecta (PE) Schott has long been used to treat cancer, undiagnosed swelling and erythema toxicum. However, its medical benefits lack support from scientific evidence. A novel lipid-soluble extract from PE has been previously verified to enhance the cytotoxicity of cis-dichlorodiammineplatinum-II (CDDP) against human cervical cancer cells in vitro. The present study evaluated the synergistic cytotoxic effects of PE and CDDP against human cervical cancer. Combination therapy of PE with CDDP exhibited synergistic cytotoxicity towards CaSki cell growth in mouse xenograft tumors. PE exhibited a cytotoxic effect on tumor size and weight, although the inhibitory ratio of tumor weight was only 26.3% in the PE-treated group. However, when mice were co-treated with PE and CDDP, the inhibitory ratio was higher than that of mice treated with CDDP alone (50.8 vs. 68.4%, respectively). The potential synergistic mechanism was likely via inhibiting the signaling E6/p53 pathway, restoring p53 function and inducing downstream tumor suppressor chain effects on apoptosis. Western blot analysis and immunohistochemistry indicated that E6 protein expression was significantly decreased upon treatment with combined PE and CDDP. The expression of p53 was increased in the combined PE and CDDP treatment group. Upregulation of p53-dependent apoptosis-associated proteins, including Bcl-2-associated X protein and cleaved caspases-9 and -3, was observed in the combined PE and CDDP treatment group. Our results present a molecular basis for the future application of the combination of PE and CDDP in the treatment of cervical cancer as a novel and pharmacologically safe chemotherapeutic strategy. [ABSTRACT FROM AUTHOR]

Herbal medicines have been recognized as an attractive approach for cancer therapy with minimal side effects. The present study investigated the type of interaction between a novel lipid-soluble extract from Pinellia pedatisecta Schott (PE) and cisplatin (CDDP) on human cervical cancer SiHa and CaSki cell lines in vitro. The mechanism of this combination was studied using cell proliferation, invasion and apoptosis assays, and by analyzing cell cycle distribution and protein expression, with a focus on DNA damage response (DDR) activation. Equipotent combinations of PE and CDDP were determined by isobologram analysis, in order to evaluate potential synergy. The combination index for SiHa cells was 0.43, and the index for CaSki cells was 0.68, indicating synergy. Treatment with PE and CDDP combined resulted in a significantly greater inhibition of invasion in the two cells, compared with either drug alone (SiHa, P<0.01; CaSki, P<0.001). This co-treatment induced significantly more apoptosis in the two cell lines, and arrested cells at the G0/G1 phase and G2/M phase in SiHa and CaSki, respectively, with a significant decrease (P<0.01) in S phase cells in the two cell lines. Combined PE and CDDP targeting synergistically enhanced the expression of markers of DDR (phosphorylation of ataxia-telangiectasia mutated, checkpoint kinase (Chk)-1, Chk-2, and γ-H2A histone family member X) in cells. These results suggest that PE and cisplatin act synergistically in cervical cancer cells with high DDR activation. The approach presented in the present study may have important implications for the pharmacological mechanism of Pinellia pedatisecta Schott and cervical cancer therapeutic strategies. [ABSTRACT FROM AUTHOR]

Rarefied gas flow into vacuum through short tubes at variable wall temperatures was studied numerically with the direct simulation Monte Carlo method. A wide range of tube wall temperatures varying from 120 to 1200K was considered, as well as several rarefaction parameters and tube aspect ratios. The mass flow rate, specific impulse, thrust, and characteristics of the gas flow field were analyzed. The results showed that the tube wall temperature, as well as the aspect ratio and rarefaction parameter, had a significant influence on the characteristics of the tube flow. The mass flow rate was found to decrease with increasing wall temperature, while the specific impulse increased. This paper reveals the combinations of rarefaction parameter and aspect ratio whereby the wall temperature has the strongest influence on the flow field of the gas, as well as on the overall macroscopic parameters. [ABSTRACT FROM AUTHOR]

In order to improve the erosion capacity of a supercritical carbon dioxide (SC-CO2) jet, the influence of a nano-silica additive on the rock erosion characteristics was experimentally investigated. By impinging the SC-CO2 jets with nano-silica mass fractions of 0 wt % (pure SC-CO2 jet), 3 wt %, 6 wt %, 9 wt %, 12 wt %, 15 wt %, and 18 wt % on specimens of red sandstone, the erosion volumes under various operating conditions were measured and analyzed. Results show that an appropriate amount of nano-silica additive can greatly enhance the erosion ability of a SC-CO2 jet. The effect on the erosion ability largely depends on the operating conditions. For instance, when the other conditions are fixed, 6 wt %, 9 wt %, 12 wt %, and 15 wt % were the optimum mass fractions, successively, with the inlet pressure increasing from 30 MPa to 60 MPa. With the increase in ambient pressure, the optimum mass fraction is unchanged under the constant inlet pressure, while it increases under the constant pressure drop. Additionally, the optimum mass fraction decreases when the fluid temperature increases. In addition, the optimal standoff distances are about five times the nozzle diameter of the nano-silica SC-CO2 jet, and three times for the pure jet. This research provides a new method for effectively enhancing the rock erosion performance of a SC-CO2 jet. [ABSTRACT FROM AUTHOR]

Amidoximated nylon-66 fiber containing double amidoxime groups per repeating unit (coded as PA66-g-PGMA-IDPAO) for the purpose of removing low uranium concentrations (1-25 mg/L) from aqueous solutions and application in simulated nuclear industry effluents was prepared by a simultaneous radiation-induced emulsion graft polymerization method. It was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and single fiber tensile strength tester. Batch adsorption experiments were conducted to investigate the effect of initial pH, sorption isotherm, adsorption kinetics, and thermodynamics. It was found that the optimum initial pH is 5.0. The sorption isotherm followed the Langmuir isotherm. The adsorption kinetics fit the pseudo-second-order model. The thermodynamics parameters revealed that the adsorption process was spontaneous and endothermic. The sorption test performed in a simulated nuclear industry effluent demonstrated a high adsorption efficiency (about 91.3%) and selectivity for uranium. [ABSTRACT FROM AUTHOR]

Ovarian cancer (OC) is the gynecological malignancy with the highest rate of mortality, and lymphatic metastasis is a critical factor in disease recurrence and prognosis. In the current study, the SKOV-3/LN403 cell line, which has high potential for lymph node metastasis was established as a result of four rounds of selection from retroperitoneal lymph nodes following intraperitoneal injections of SKOV-3 ovarian adenocarcinoma cells. In comparison to the parental SKOV-3 cell line, SKOV-3/LN403 has a higher rate of proliferation, is more invasive and exhibits greater resistance to paclitaxel. Subsequently, a novel animal model of OC lymphatic metastasis was developed with SKOV-3/LN403 cells and a high incidence of positive metastatic lymph nodes, peritoneal dissemination and bloody ascites were observed, which mimicked the clinical outcome of patients with OC. Analysis of the gene expression profiles of SKOV-3 and SKOV-3/LN403 cells identified several genes and pathways that may be involved in lymphatic metastasis of OC. The induction of focal adhesion kinase expression provides a potential therapeutic target for OC lymphatic metastasis. [ABSTRACT FROM AUTHOR]

Background We previously identified platelet-activating factor receptor (PAFR) as being overexpressed in ovarian cancer and found that its ligand PAF evoked EGFR phosphorylation using the phospho-antibody microarray. Epidermal growth factor receptor (EGFR) are also overexpressed in ovarian cancer and contribute to the growth of ovarian cancer cells. Here, we investigated the mechanisms of crosstalk between PAFR and EGFR signaling in ovarian cancer cells to further determine whether the interaction between PAFR and GFR synergistic contribute to the progression of ovarian cancer. Methods Expression and localization of PAFR in several ovarian cancer cell lines were assessed by Western blot, realtime-PCR and immunofluorescence. The ovarian cancer cells were stimulated with PAF or PAF and in some experiments also pharmacological inhibitors. Phosphorylation of proteins in signaling pathways were measured by Western blot. HB-EGF concentrations of the supernatant from stimulated ovarian cancer cells were measured by enzyme-linked immunosorbent assay. Results Our data show that PAF increases EGFR phosphorylation through PAFR in a time-and dose-dependent manner in SKOV-3 ovarian cancer cells. This transactivation is dependent on phospholipase C-β and intracellular calcium signaling. This pathway is also Src tyrosine kinase-and metalloproteinase-dependent. PAF triggers EGFR activation through the increased heparin-binding EGF-like growth factor (HB-EGF) release in metalloprotease-dependent manner. Several studies involving EGFR transactivation through G-protein coupled receptor (GPCR) have demonstrated EGFR-dependent increase in ERK1/2 phosphorylation. Yet in SKOV-3 cells, PAF treatment also increases ERK1/2 phosphorylation in a EGFR-independent manner. Conclusions The results suggest that in SKOV-3 ovarian cancer cells, PAF transactivates EGFR and downstream ERK pathways, thus diversifying the GPCR-mediated signal. The crosstalk between PAFR and EGFR suggests a potentially important signaling linkage between inflammatory and growth factor signaling in ovarian cancer cells. [ABSTRACT FROM AUTHOR]

A nitro-decorated NbO-type metal-organic framework, Cu2NTPTB (NJU-Bai 14; H4NTPTB = 2'-nitro-[1,1':4',1"-terphenyl]-3,3",5,5"- tetracarboxylic acid), was synthesized and structurally character- ized. It exhibited high permanent porosity with a BET surface area of 2384 m² g-1, improved adsorption selectivity of CO2/CH4 (6.5) and CO2/N2 (20.8) at 298 K and 1 bar, high excess unsaturation CO2 uptake (94.0 wt%) at 273 K and 20 bar, and high methane total uptake of 184 cm³ cm-3 at 290 K and 35 bar. [ABSTRACT FROM AUTHOR]

Background Genetic alterations, including the overexpression of epidermal growth factor receptor (EGFR), play a crucial role in ovarian carcinogenesis. To date, EGFR targeting has shown limited antitumor effects in ovarian cancer when administered as monotherapy. We previously identified platelet-activating factor receptor (PAFR) as being overexpressed in ovarian cancer and found that its ligand PAF evoked EGFR phosphorylation. To determine whether PAFR targeting can enhance the antitumor efficacy of EGFR inhibition, we investigated the effects of a PAFR antagonist (WEB2086) in conjunction with an EGFR inhibitor (AG1478). Methods The expression of EGFR and PAFR in CAOV-3 and SKOV-3 ovarian cancer cell lines was measured by Western blot and immunocytochemistry. Synergy was determined using isobologram analysis. The effects of combined PAFR and EGFR targeting on both cells were assessed by using CCK-8, transwell, flow cytometry, western blot analysis. In vivo studies were conducted using CAOV-3 cells xenografted in nu/nu mice. Results Treatment with combination WEB2086 and AG1478 resulted in significantly greater inhibition of proliferation and invasion compared to either drug alone. When examining equipotent combinations of WEB2086 and AG1478 to determine potential synergy, a combination index (CI) of 0.49 was identified for CAOV-3 cells and a CI of 0.58 for SKOV- 3 cells indicating synergy. This co-inhibition induced significantly more apoptosis and arrested the cells at G0/G1 phase in both cell lines. The activation of PAFR and/or EGFR induced phosphorylation of the mTOR, AKT, and MAPK pathways. Combined PAFR and EGFR targeting synergistically diminished the expression of PAFR and EGFR phosphorylation and downstream signaling. In vivo studies further verified the antitumor effects of combined PAFR and EGFR targeting in a CAOV-3 xenograft model. Conclusions These results suggest that WEB2086 and AG1478 are synergistic in ovarian cancer cells with high expression of both PAFR and EGFR. The presented approach may have important therapeutic implications in the treatment of ovarian cancer patients. [ABSTRACT FROM AUTHOR]

Background Among the pro-inflammatory lipid mediators, platelet-activating factor (PAF) is a major primary and secondary messenger that binds to the PAF-receptor (PAFR). Epidermal growth factor (EGF) is a polypeptide growth factor that binds to the EGF-receptor (EGFR). Evidence suggests that both PAF and EGF play a significant role in oncogenic transformation, tumor growth, neoangiogenesis and metastasis, including ovarian cancer. PAF has the potential to transactivate EGFR in ovarian cancer cells. This study explores the mechanisms involved in EGF-induced PAF production. Methods The effect of EGF on PAF production in ovarian cancer cells was observed using enzymelinked immunosorbent assay. The receptors transactivation and the role of cytosolic phospholipase A2 (cPLA2) in modulating PAF production induced by EGF was assessed using pharmacological inhibitors, si-RNA knockdown, targeted gene overexpression and immunocytochemistry. The signaling pathways invovled in PAF production induced by EGF in ovarian cancer cells were assessed. Results We demonstrate that EGF increases the production of PAF in CAOV3 and SKOV3 ovarian cancer cell lines. EGF induces the transactivation of PAFR, which can be blocked by an EGFR inhibitor. Inhibition of EGFR and/or PAFR blocks PAF production in response to EGF. EGF-induced PAF production involves the phosphorylation of extracellular-regulated protein kinase (ERK) and cytosolic phospholipase A2 (cPLA2). A cPLA2 inhibitor blocks EGF-induced PAF production as well as si-cPLA2, while overexpression of cPLA2 increases PAF production. Conclusions These results indicate that EGF stimulates PAF production in ovarian cancer cells in a manner that requires cPLA2. We have also determined that crosstalk can occur bidirectionally between EGFR and PAFR, suggesting that EGF-induced PAF production could result in positive feedback that acts on the PAF-receptor to promote ovarian cancer progression. [ABSTRACT FROM AUTHOR]

The effect of surface modification of Indium tin oxide by a NH2+ ion implantation technique has been studied to detect daunorubicin, an anticancer drug. The current was linearly dependent on the scan rate, indicating that the direct electrochemistry of daunorubicin in that case was a surface-controlled electrode process. The NH2/ITO electrode successfully detected the reduction signals of daunorubicin in the linear range of 1.0 x 10-9 ~3.0 x 10-6 M and the detection limit was 2.0 x 10-10 M (at S/N = 3). NH2/ITO electrode exhibited high sensitivity, selectivity and good stability, and would be valuable for clinical assay of daunorubicin. [ABSTRACT FROM AUTHOR]

This article presents an experimental investigation carried out to understand the mechanical behavior of composite materials made of 3D stitched woven-knitted basalt fabrics. The innovative preforms used consist of two outer layers of a plain woven fabric combined with two inner layers of weft-knitted fabrics. The weft-knitted fabrics selected for the study were varied plain knit, 1 x 1 rib, Milano, and interlock. The fabric layers were stitched together with Kevlar yarns. These 3D stitched preforms were impregnated with polyester resin using resin transfer molding, and the corresponding composites obtained were tested under tensile, bending, and impact loads. The results obtained show that the type of knitted structure significantly influences the mechanical performance of the 3D stitched woven-knitted composites. The composite using interlock structure as the inner layers has the best results concerning energy absorption and tensile strength. The varied plain knit structure has proved to be the best suited to impart stiffness as it provides the highest Young's modulus among the above four knitted structures. [ABSTRACT FROM AUTHOR]

On the basis of the ligand of 5-(pyridin-3-yl)isophthalic acid (H2L), a new distorted [Mn2(COO)4N2] cluster based metal-organic framework with (3,3,6) topology, [Mn2(L)2DMF]·DMF·MeOH (NJU-Bai33; DMF = N,N-dimethylformamide), was synthesized, which exhibits a new point (Schläfli) symbol of (4·62)2(42·68·85), contains open metal sites, and shows selective adsorption of CO2 over N2 and CH4 with CO2 uptake amounts high up to 7.9 and 4.2 wt % at 0.15 bar and at 273 and 298 K, respectively. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the antioxidant and anticancer activities of phenolics from the leaf extract of Toona sinensis (TS). Methods: Acetone leaf extract of TS was screened for total phenolic and flavanoid contents, and the flanonoids were subjected to high performance liquid chromatographic (HPLC) analysis. Antioxidant properties were assessed via oxygen radical absorbance capacity (ORAC), peroxyl radical scavenging capacity (PSC) and cellular antioxidant activity (CAA), while anti-proliferative activity ins HepG2 cell line was assessed using methylene blue assay. Results: The extract contained 36.02 ± 0.24 mg of gallic acid equiv/g dry weight (DW) and 20.24 ± 1.73 mg of catechin equiv/g DW of total phenolic and total flavonoid, respectively. The levels of rutin and quercitrin were 0.51 and 19.55 mg/g, respectively. Epicatechin, gallic acid, quercitin, isoquercetin were not detected. The extract showed significant antioxidant potential and high anti-proliferation capacity with low cytotoxicity against HepG2 cell in vitro. The underlying mechanism of anti-proliferative effect was induction of apoptosis. Conclusion: TS leaf extract possesses significant in vitro antioxidant properties and anti-proliferative effect against HepG2 cells, which make it a potential anticancer drug source. [ABSTRACT FROM AUTHOR]

A new approach to improve the tensile ductility of CuZr-based bulk metallic glasses without significant reduction in high strength is reported. After doping of Nb into CuZr-based alloy, a composite was formed with a combination of high strength, large tensile plasticity and strong work-hardening effect. The addition of Nb led to a uniform distribution of single B2-CuZr phase in the glassy matrix. The optimal tensile properties were attributed to the deformation-induced martensitic transformation of the B2-CuZr phase, which in turn interacted with the glassy matrix. In addition, the drastic adiabatic heating on the fracture region also contributed to the increase in tensile plasticity. [ABSTRACT FROM AUTHOR]

Boron (B) is widely acknowledged as the preferred fuel for rocket ramjets. Nevertheless, the presence of boron oxide (B 2 O 3) on the surface of boron impedes the interaction between the oxidized component and the internal active component B, leading to challenges in ignition and constraints on reactivity and combustion efficiency. To mitigate these issues, high-energy materials featuring a B@Mg@KNO 3 coating structure were efficiently and expeditiously prepared using a solvent extraction method. The B@Mg@KNO 3 material distributes magnesium inside and outside the B shell, while KNO 3 serves as the load layer. The addition of the load layer facilitates closer contact between Mg and the oxidizer, reducing the diffusion distance between oxygen and fuel. As a result, the ignition energy of B is reduced, and the energy release characteristic of B is improved through multi-effect coordination. In comparison with the B/KNO 3 sample, the heat release of B@Mg@KNO 3 increased by 113.1 %, the ignition temperature decreased by 50 °C, and the ignition energy decreased by 62.5 % as indicated by the ignition test. The flame temperature increased by 51.8 %, the combustion efficiency of B@Mg@KNO 3 increased by 23.92 %, and the apparent activation energy decreased by 109.6 kJ/mol. Consequently, B@Mg@KNO 3 is anticipated to expedite the application and advancement of boron-based rocket ramjet engines. • To address the challenges associated with boron ignition and combustion, B@Mg@KNO 3 high-energy materials with a coated structure were synthesized using solvent extraction. • In comparison to the B/KNO 3 sample, the heat release of B@Mg@KNO 3 increased by 113.1 %, accompanied by a 50 °C decrease in ignition temperature. Additionally, the ignition test revealed a 62.5 % reduction in ignition energy. The flame temperature saw a 51.8 % increase, while the combustion efficiency of B@Mg@KNO 3 improved by 23.92 %, and the apparent activation energy decreased by 109.6 kJ/mol. • The mechanism underlying the synergistic enhancement of the ignition and energy release performance of B by B@Mg@KNO 3 was validated through XRD, XPS, SEM, EDS, and other characterization techniques. [ABSTRACT FROM AUTHOR]

• TiO 2 -ZrO 2 Co-doped MASB glass-ceramic with low thermal expansion was developed. • The values of the crystallization kinetics parameters for crystal growth calculated using various methods were consistent. • The stability of MAS glasses increased by replacing TiO 2 with ZrO 2. • A proper amount of TiO 2 and ZrO 2 contributed to the crystallization and formation of cordierite. • Rutile or zircon phase will precipitate from the parent glasses due to TiO 2 -ZrO 2 doping excessive. TiO 2 –ZrO 2 -codoped MgO–B 2 O 3 –Al 2 O 3 –SiO 2 glass-ceramics were prepared using the traditional melting method. The effects of replacing TiO 2 with ZrO 2 on the glass stability (GS), crystallization behavior, structures, and properties of the obtained samples were studied. Results showed that the addition of ZrO 2 increased the GS, which decreased the crystallization ability of the samples. When the heat treatment temperature was increased from 900 °C to 1000 °C, the mullite and quartz phases first precipitated in the glass matrix, and then converted into cordierite. Because of the low solubility of TiO 2 and ZrO 2 in this glass system, the rutile and zircon phases will precipitate from the parent glasses. Owing to changes in the composition and structure of the samples, the density and Vickers hardness increased, while the coefficient of thermal expansion of the samples first decreased and then increased when TiO 2 was replaced with ZrO 2. [ABSTRACT FROM AUTHOR]

Ecological product is an innovative practice for ecological valuations in China. Due to the influence of historical conditions and development stages in China, research on the realization of ecological valuations has lagged. In the new era, the construction of an ecological civilization guided by the “Two Mountains” theory has been promoted to the national strategic level and is supporting the growth of theoretical research and practical exploration based on the understanding of ecological product values. We want to innovate and improve the system used to realize the value of ecological products by applying the existing research, which focuses on the concept definition of ecological products and their correlation theories. Through systematic expansion and upgrades in this system, the evaluation accuracy of ecological products can be improved, providing valuable references for further practical exploration and promoting an ecological culture in China.