The low-cycle fatigue （LCF） behavior of directionally solidified nickel-based superalloy Ti-6A1-4V was studied under bare and electron beam welding condi- tions at room temperature. Results show ...that： （1） under the same test conditions, all the joints exhibit lower LCF lifetime than Ti-6A1-4V; （2） the failure of welded structures is mainly ascribed to the welding defect. A novel lifetime prediction methodology based on continuum damage mechanics is proposed to predict the lifetime of Ti-6A1-4V and its welded joints.
Objective： The Notch signaling pathway plays an important role in the stem cell signaling network and contributes to tumorigenesis. However, the functions of Notch signaling in ovarian cancer stem ...cells （OCSCs） are not well understood. We aimed to investigate the effects of Notch blockade on self-renewal and stemness maintenance of OCSCs. Methods： Ovarian cancer stem-like cells were enriched from ovarian cancer cell lines in serum-free medium. A γ-secretase inhibitor, （DAPT）, was used to block Notch signaling. MTT assays were performed to assess self-renewal and proliferation inhibition, flow cytometry was performed to analyze cell surface marker and immunofluorescence, Western Blot and Real-time RT-PCR assays were performed to detect Oct4 and Sox2 protein and mRNA expression of the Ovarian cancer stem-like cells treated with DAPT. Results： Notch blockade markedly inhibits self-renewal and proliferation of ovarian cancer stem-like cells, significantly downregulates the expression of OCSCs-specific surface markers, and reduces protein and mRNA expression of Oct4 and Sox2 in OCSC-like cells. Conclusion： Our results suggest that Notch signaling is not only critical for the self-renewal and proliferation of OCSCs, but also for the stemness maintenance of OCSCs. The γ-secretase inhibitor is a promising treatment targeting OCSCs.
Low light stress is one of the most important factors affecting photosynthesis and growth in winter production of cucumber （Cucumis sativus L.） in solar greenhouses in northern China. Here, two ...genotypes of cucumber （Deltastar and Jinyan 2） are used to determine the effect of low light stress on Rubisco expression and photosynthesis of leaves from emergence to senescence. During leaf development, the net photosynthetic rate （PN）, stomatal conductance （gs）, Rubisco initial activity and activation state, transcript levels of rbcL and rbcS, and the abundance of rbcL and rbcS DNA in these two genotypes increase rapidly to reach maximum in 10-20 d, and then decrease gradually. Meanwhile, the actual photosystem II efficiency （OpSll） of cucumber leaves slowly increased in the early leaf developing stages, but it declined quickly in leaf senescent stages, accompanied by an increased non-photochemical quenching （NPQ）. Moreover, PN, gs, initial Rubisco activity, and abundance of protein, mRNA and DNA of Rubisco subunits of leaves grown under 100 μmol m^-2 s^-1 are lower, and require more time to reach their maxima than those grown under 600 μmol m^-2 s^-1 during leaf development. All these results suggest that lower photosynthetic capacity of cucumber leaves from emergence to senescence under low light stress is probably due to down-regulated Rubisco gene expression in transcript and protein levels, and decreased initial and total activity as well as activation state of Rubisco. Deltastar performs better than Jinyan 2 under low light stress.
In order to improve the dynamical recognition efficiency of radio frequency identification (RFID) system and to reduce the reading error of measurement, a dynamical analysis method is proposed in ...this paper, in which Fisher information matrix is introduced into RFID multi-tag distribution. The optimal selection of system's test point and the positioning effect of different planning paths could be evaluated by the Fisher information matrix with state parameters. In view of the rational distribution of RFID tags, the multi-tag geometrical patterns are given in dynamic internet of things (IOT) environment. The numerical simulation is shown that the tag number, path and speed could directly affect the RFID system's performance. Furthermore, the planning paths, limiting target speed and adjusting test points in practical applications could improve the dynamic recognition efficiency, by analysing the recognition efficiency curve.
The present study reports a sensitive electro-analytical method for the simultaneous determination of dihydroxybenzene isomers by using a thiadiazole film electrode, which was readily prepared by ...electropolymerization of 2,5-dimercapto-1,3,4-thiadiazole on a glassy carbon electrode with cyclic voltammetry. The functionalized electrode has a distinguishable and sensitive response to dihydroxybenzene isomers. Under the optimized conditions, the linear stripping peak currents showed good linear relationships with hydroquinone, catechol and resorcinol at concentration ranges 0.50-120, 0.50-110 and 1.00-110 μmol/L, and the detection limits are 0.1, 0.1 and 0.3 μmol/L, respectively. The proposed method is applicable to the simultaneous determination of dihydroxybenzene isomers in real samples with the relative standard deviations of less than 5.7% and the recovery rates of 95.6%-106%. The constructed electrode is characterized by simple preparation, good selectivity, and high sensitivity advantages.
To obtain highly fire-safe epoxy resin (EP), piperazine-modified ammonium polyphosphate (PAz-APP) with multiple active -NH- groups was prepared and utilized as a highly effective flame-retardant ...hardener. After curing by PAz-APP as a monocomponent hardener, cross-linked networks containing both tertiary amino and ether linkages were obtained, which resulted in two glass transitions. Thanks to the phosphorus-containing inorganic part, PAz-APP brought excellent flame retardance and smoke suppression efficiency to the EP system. The cured sample passed V-0 rating (UL-94) with only 7.5 wt% addition of PAz-APP. Cone calorimetric results suggested that, compared with PAz/EP (as a reference sample), both the peak-heat release rate (PHRR) and total smoke production (TSP) of PAz-APP 15/EP (15 wt% addition) sharply dropped by 81.5% and 80.0%, respectively. By analyzing the chemical constitution of the decomposing residues at different temperatures, it was noticed that PAz-APP mainly acted as a flame retardant in the condensed phase
via
the formation of phosphorus-rich char. Dynamic mechanical analysis (DMA) illustrated that the main glass transition temperature (
T
g
) of PAz-APP 15/EP was as high as 162.4 °C. Furthermore, the incorporation of PAz-APP did not worsen the mechanical properties, but contrarily, improved the impact strength.
PAz-APP (as a monocomponent hardener) can bring excellent flame retardance and smoke suppression efficiency to the EP system without sacrificing the mechanical properties and glass transition temperature.
Monte Carlo transport simulations of a full-core reactor with a high-fidelity structure have been made possible by modern-day computing capabilities.Performing transport-burnup calculations of a ...full-core model typically includes millions of burnup areas requiring hundreds of gigabytes of memory for burnup-related tallies.This paper presents the study of a parallel computing method for full-core Monte Carlo transport-burnup calculations and the development of a thread-level data decomposition method.The proposed method decomposes tally accumulators into different threads and improves the parallel communication pattern and memory access efficiency.A typical pressurized water reactor burnup assembly along with the benchmark for evaluation and validation of reactor simulations model was used to test the proposed method.The result indicates that the method effectively reduces memory consumption and maintains high parallel efficiency.
An improved IPv6 routing lookup algorithm of WSN Hong Jiang; Qing-song Yu; Xiao-lei Yu
2011 Eighth International Conference on Fuzzy Systems and Knowledge Discovery (FSKD),
2011-July, Volume:
4
Conference Proceeding
The research in WSN has become more and more active and its applications are also extending. However, many of the IPv6 routing lookup algorithms used nowadays cannot adapt to the new requirements of ...IPv6 and impact the performance of WSN. An improved longest prefix matching routing algorithm based on IPv6 is proposed in this paper. The network prefixes and the destination addresses are transformed into the decimal system, then the network prefixes are stored using Scalable Bloom Filter and the destination addresses are stored segmentally to reduce the number of filters. Fast lookup speed is achieved by equitable distribution of the address prefixes. Simulation results show that the improved algorithm has better performance in time efficiency and storage efficiency.
Dear Editor, We present here a case report of＂Krukenberg tumor＂ in male. In 1896, Friedrich Krukenberg （1871 - 1946）, a German gynecologist and pathologist, described what he presumed as a new type ...of primary ovarian neoplasm. The true metastatic nature of this lesion was established 6 years later and termed as＂Krukenberg tumor＂？ Now, the term ＂Krukenberg tumor＂ has been used either as a broad definition to indicate all metastatic tumors to the ovaries or to describe just metastatic tumors from the gastrointestinal tract containing the typical signet ring cell with intracellular mucin.2-6 Our case, as an analog in male, has criteria to be called ＂Krukenberg tumor＂ in male.
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