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Protein kinase CK2 is a ubiquitously expressed kinase in eukaryotes, which is known to phosphorylate many protein substrates. Because CK2 is involved in the regulation of various signaling pathways, we wondered whether CK2 participated in the regulation of ionizing radiation (IR) induced biological process. In this study, we investigated the effect of IR on the subcellular localization and kinase activity in human non-small cell lung cancer (NSCLC) cells. Immunofluorescent results showed that CK2 subunits shuttle into the nucleus mostly beginning 1 h after IR and lasting more than 6 h. We also conducted in vitro kinase assay and observed an increase in CK2 kinase activity at 6 h after IR. Furthermore, an increase in S phase was observed at 6 h after IR. Colony formation assay results demonstrated that CK2 inhibitor CX-4945 significantly enhanced the effect of irradiation in NSCLC cells. These results indicated that CK2 may be implicated in the regulation of IR-induced biological process.

Background: Nasopharyngeal carcinoma (NPC) is the common malignant tumor of nasopharynx in southern China and other southeastern Asian countries. MicroRNAs (miRNAs) have been shown to play important roles in carcinogenesis. Recently, miR-34c-3p and miR-18a-5p have been found to be involved in carcinogenesis of NPC. Furthermore, platelets in NPC patients may acquire RNAs from NPC cells and turn into "tumor-educated platelet (TEP)", which may serve as potential biomarkers for a diagnosis of NPC. However, the expression profiles of TEP miR-34c-3p and miR-18a-5p in NPC patients and their diagnostic values are yet to be determined. Aims: To investigate expression levels of TEP miR-34c-3p and miR-18a-5p and determine their diagnostic values for NPC. Materials and methods: Relative quantitative real-time PCR was used to determine the expression levels of TEP miR-34c-3p and miR-18a-5p in NPC patients (n=54) as compared to normal subjects (n=36). The receiver operating characteristic (ROC) curve analysis was performed to assess the diagnostic values of TEP miR-34c-3p and miR-18a-5p for NPC. Results: The expression levels of TEP miR-34c-3p and miR-18a-5p were significantly higher in NPC patients as compared to healthy subjects. The ROC analysis showed that the area under the ROC curve (AUC), sensitivity, specificity and accuracy for TEP miR-34c-3p, miR-18a-5p, or a combination of both miRNAs for NPC diagnostic tests were 0.952, 94.44%, 86.11%, 91.11%, or 0.884, 85.19%, 86.11%, 85.55%, or 0.954, 92.59%, 86.11%, 90.00%, respectively. No correlation was found between expression levels of TEP miR-34c-3p or miR-18a-5p and patients' demographic variables and their NPC tumor/node/metastasis stages. The positive rates of TEP miR-34c-3p and miR-18a-5p for NPC diagnosis were 93.8% and 87.5%, respectively, which were significantly higher than Epstein-Barr virus DNA with a positive rate of 66.7%. Conclusion: The expression levels of TEP miR-34c-3p and miR-18a-5p are upregulated in NPC, rendering a significant clinical value for NPC diagnosis. The TEP miRNAs might serve as a novel type of liquid biopsies for NPC diagnosis.

Problem solving is considered a fundamental human skill. However, large-scale assessment of problem solving in K-12 education remains a challenging task. Researchers have argued for the development of an enhanced assessment approach through joint effort from multiple disciplines. In this study, a three-stage approach based on an evidence-centered design framework is proposed to analyze problem-solving behavior, abilities, and performance. The approach is applied to assess the online problem solving of 554 students in a Shanghai primary school. The study reveals four clusters with distinctive problem-solving behavior, abilities, and performance. The findings of this approach also corroborate the results of the Programme for International Student Assessment of Shanghai students’ problem-solving performance. The implications and limitations of this study are also discussed.

In this paper, a microstrip tri-band bandpass filter (BPF) utilizing square ring loaded resonator is proposed. A pair of bent perturbation stubs is installed to the ring resonator so as to control resonant modes of the ring. The first three modes are used for tri-band BPF design. In order to control the second and third resonant modes, two pairs of square patches and loaded open stubs are added, and then two asymmetric resonators are cascaded for tri-band operation. Based on the transmission line theory, even- and odd-mode analysis method is used to deduce the resonant frequencies. According to the resonant conditions, a kind of tri-band BPF can be flexibly designed. Finally, two filters are designed as examples in a comprehensive way for demonstration, and one design with passbands located at 2.4, 3.5 and 5.2 GHz is fabricated. Measured results agree well with the simulated ones.

A generalized formulation of Cauchy method for multiplexer rational model extraction is presented in this paper. This new technique can extract the multiplexer rational models from either measurement or electromagnetic simulation results. The generalized formulation of Cauchy method takes into account the relationship between the transmission coefficients and reflection coefficients of each channel filter. It is suitable for multiplexers whose channel filters are connected through resonating junction. The total least square method is applied to solve the system matrix. The new technique presented in this paper is suitable for lossless case as well as lossy case and is verified by lossless triplexer and circuit simulation lossy triplexer examples successfully.

A new type of dual-mode planar filter with flexible transmission zeros using slot-line square loop resonator (SSLR) is presented. This resonator is based on the slot-line loop on the ground plane. Four slot-line stepped impedance stubs are loaded in the center loop to achieve compact size and harmonic suppression. Two sizes of slot patches added at the inner corners can split the degenerate modes and adjust the coupling between even and odd modes. A pair of T-shaped feed lines on the top plane can provide flexible source–load coupling, which leads to symmetrical or asymmetrical frequency response. Both the equivalent circuit and coupling matrix analysis methods are utilized to design the dual-mode filter. Two kinds of filters operating at 3.35 and 3.80 GHz with wideband and flexible transmission zeros are designed and fabricated.

In this paper, a novel triple-band microstrip filter with improved out-of-band suppression is presented. The theoretical design of triple-band filter is based on frequency transformation method, which is then realized by a group of triple-band resonators as the building block of the filter. Two open stubs with different lengths are loaded directly in the middle of two resonators to introduce a pair of transmission zeros, which achieves high out-of-band suppression filtering response with no need of cross-coupling. To validate the method, a practical triple-band filter with pass-bands at 3.3–3.4 GHz, 3.5–3.6 GHz, 3.7–3.8 GHz and transmission zeros at 3.1 GHz, 4 GHz is designed and fabricated.

A novel dual-band filter using open loop ring resonator (OLRR) and defected stepped impedance resonator (DSIR) is presented in this paper. The OLRR forms one pass on the upper plane, and the DSIR forms the other pass on the lower plane. A proper designed feed structure is analyzed and used, which can provide desired external couplings to the two passes independently. At last, a dual-band filter with cascaded quadruplet (CQ) topology is designed and fabricated, which operates at WLAN bands 2.45/5.25 GHz. The simulated and measured results show good agreements and validate the proposed design method.

SummaryChanges in the concentrations of trans-resveratrol (Res) and other phenolic compounds in the skin and seeds of red grape (Vitis vinifera × V. amurensis ‘Beiquan’) during low temperature storage (−1o ± 0.5oC) after post-harvest UV-B and UV-C irradiation and incubation at room temperature (25oC) were evaluated. No obvious changes in Res levels were observed in control and UV-B-irradiated grape skins after 14 d. A higher content of Res was recorded in UV-B-irradiated grape skins for only 7 d in cold storage, but the content was highest in UV-C-irradiated grape skins for the entire period (28 d) in cold storage. Total levels of anthocyanins in grape skins after either UV treatment were significantly higher than in controls during the first 7 d of storage, while only those in UV-B-treated skins were significantly higher than controls during the later period (from 21 – 28 d) of storage, due to sharp declines in levels of the five main anthocyanins in UV-C-treated grape skins. Total flavan-3-ol and flavon...

This paper presents a novel wideband coaxial filter with two transmission zeros. The synthesis process of this kind of filter is derived in detail, and then the curve fitting method is used to obtain the relationship between the electrical values and their corresponding physical dimension. Two series resonant loops are introduced to provide two transmission zeros in the low rejection band. Finally, a wideband coaxial filter centered at 305 MHz with an ultra-wide bandwidth of 62% is successfully designed, simulated and fabricated. Two transmission zeros are designed to be located at 183 MHz and 176 MHz, which improve the out-of-band suppression obviously. The theoretical, simulated and experimental results with good agreement are given in this work.

A novel bandpass filter with two dual-mode cavities based on the substrate integrated waveguide (SIW) is presented. By making use of the inductive discontinuities in an SIW cavity, two degenerate modes can be excited. Due to the phase difference of the two modes in each cavity, two transmission zeros on each side of the passband are created, so the out-of-band rejection of the filter is significantly improved. An SIW dual-mode filter with a center frequency of 12 GHz has been fabricated and measured. The experimental results agree well with the simulation results.

Performance of amplifying evanescent wave is investigated on the basis of simulation. Three cases of waveguides loading SRR resonators, strip lines and composite meta-materials are analyzed individually. In certain frequencies, these three kinds of arrays all have the ability of evanescent wave amplification.

A wideband cross coupled bandpass filter making use of square split-ring resonator (SRR) defected ground structure (DGS) and parallel microstrip feed line is presented in this paper. The coupling between a pair of SRR DGS is much larger than that of the conventional SRR, which is fully investigated and applied to the design of wideband cross coupled filter. By extracting the coupling coefficient of various coupling structures and external quality factors of various feed structures, a SRR DGS four-pole filter with center frequency of 2.2 GHz and bandwidth of 20% is designed and fabricated.

This paper presents a novel dual-band banpass filter using microstrip open-loop resonators. A new microstrip unit of dual-band bandpass filter is introduced, which can be used as unit element of duan-band filter design. The two open-loop resonators are treated as passband resonator and stopband resonator in analysis, respectively. A five-pole C-band dual-band bandpsss filter has been designed and fabricated. The measured results show a good agreement with the simulated results.

This paper presents a novel synthesis process for wideband coaxial filter terminated with capacitors. At very high frequency and ultra-high frequency, we make use of helix as series inductor, dielectric disk as series capacitor, gap between inner metal disk and outer metal tube as shunt capacitor. By using the proposed synthesis technology and the extracted element formulas, two wideband quasilumped coaxial filters within different frequency ranges are designed and fabricated. Then they are directly connected to form a diplexer by using coaxial lines as impedance transformers. The diplexer can be used in a transceiver system combining two signals at 235 ∼ 280 MHz (VHF) and 315 ∼ 360 MHz (UHF) into one signal before the transmitted antenna.

The equivalent-circuit of a split-ring resonator (SRR) defected ground structure (DGS) is investigated in this paper. The dependence of the transmission characteristic on the dimension of a split ring, such as side-length and split-gap, is analyzed in detail. In addition, an improved SRR DGS cell model with open stubs loaded on the conductor line is then presented to improve the out-band suppression. By using the equivalent-circuit analytical method, an S-band microstrip low-pass filter with perfect low-pass characteristic and high out-band suppression is designed and fabricated.

A method of improving the gain of circular waveguide array antenna using one-dimensional (1-D) electromagnetic band-gap (EBG) structure is proposed in this paper. The detailed analysis is made to study the radiation characteristics of circular waveguide antenna and its array with 1-D EBG structure. The simulation and experimental results show an about 7 dB addition in the antenna gain in compared with the conventional antenna, which proves that the radiation characteristics of antenna array using EBG structure are improved.

A design method of tubular filter based on S-parameter curve-fitting method is presented, and a synthesis process from low-pass prototype to tubular band-pass filter is also analyzed. By using step-increasing theory, the curve-fitting process for designing tubular filter is proposed in particular. This method not only makes sure that the values of serial elements are accurate in each simulated process, but also reduces the factors which influence the values of shunted elements, and decreases the complexity in determining the element size.

SummaryFive qualitative traits, peach/nectarine, white/yellow flesh, freestone/clingstone, speckled/non-speckled skin and red flesh/non-red flesh colour were studied in terms of their relationships to sugar and acid concentrations in an unselected Prunus persica P. davidiana population in 2001 and 2002. Mean sucrose, sorbitol, total sugar, quinate and total acid concentrations and soluble solids content of nectarine genotypes were significantly higher than those of peach genotypes in both years. Mean sucrose, sorbitol, total sugar concentrations and soluble solids content in genotypes with skin speckles were significantly higher than those in genotypes without skin speckles. Skin speckle had no obvious effect on mean acid concentrations in both years. There were few significant differences in mean sugar and acid concentrations between yellow- and white-fleshed, freestone and clingstone, or red flesh and non-red flesh coloured genotypes in both years. The five qualitative traits are discussed from a breedi...