In this article, Pb2Ba1.7Sr0.3Ca2Cu3O10+δ superconductor material was synthesized using conventional solid-state reaction method. X-ray diffraction (XRD) analysis demonstrated one dominant phase 2223 and some impurities in the product powder. The strongest peaks in the XRD pattern were successfully indexed assuming a pseudo-tetragonal cell with lattice constants of a = 3.732, b = 3.733 and c = 14.75 Å for a Pb-Based compound. The crystallite size and lattice strain between the layers of the studied compound were estimated using several methods, namely the Scherrer, Williamson-Hall (W.H), sizestrain plot (SSP) and Halder Wagner (H.W) approach. The values of crystallite size, calculated by Scherrer, W.H, SSP and H.W methods, were 89.4540774, 86.658638, 87.7555823 and 85.470086 Å, respectively. Moreover, the lattice strain values obtained by W.H, SSP and H.W methods were 0.0063240, 0.006325 and 0.006, respectively. It was noted that all crystallite size results are consistent; however, the best method is the size-strain plot because it gave a value of R2 approaching one. Furthermore, degree of crystallites was calculated and found to be 59.003321%. Resistivity analysis suggests zero-resistance, which is typical of superconducting materials at critical temperature. Four-probe technique was utilized to measure the critical temperature at onset Tc(onset), zero resistivity Tc(off set), and transition (width ΔT), corresponding to temperatures of 128 K, 116 K, and 12 K, respectively.

Oral squamous cell carcinoma (OSCC) metastasis is characterized by distant metastasis and local recurrence. Combined chemotherapy with cisplatin and 5-fluorouracil is routinely used to treat patients with OSCC, and the combined use of gefitinib with cytotoxic drugs has been reported to enhance the sensitivity of cancer cells in vitro . However, the development of drug resistance because of prolonged chemotherapy is inevitable, leading to a poor prognosis. Therefore, understanding alterations in signaling pathways and gene expression is crucial for overcoming the development of drug resistance. However, the altered characterization of Ca2+ signaling in drug-resistant OSCC cells remains unclear. In this study, we investigated alterations in intracellular Ca2+ ([Ca2+]i) mobilization upon the development of gefitinib resistance in human tongue squamous carcinoma cell line (HSC)-3 and HSC-4 using ratiometric analysis. This study demonstrated the presence of altered epidermal growth factor- and purinergic agonist-mediated [Ca2+]i mobilization in gefitinib-resistant OSCC cells. Moreover, Ca2+ content in the endoplasmic reticulum, store-operated calcium entry, and lysosomal Ca2+ release through the transient receptor potential mucolipin 1, were confirmed to be significantly reduced upon the development of apoptosis resistance. Consistent with [Ca2+]i mobilization, we identified modified expression levels of Ca2+ signaling-related genes in gefitinib-resistant cells. Taken together, we propose that the regulation of [Ca2+]i mobilization and related gene expression can be a new strategy to overcome drug resistance in patients with cancer.

We present an updated version of the multilayer spectral inversion (MLSI) recently proposed as a technique to infer the physical parameters of plasmas in the solar chromosphere from a strong absorption line. In the original MLSI, the absorption prole was constant over each layer of the chromosphere, whereas the source function was allowed to vary with optical depth. In our updated MLSI, the absorption prole is allowed to vary with optical depth in each layer and kept continuous at the interface of two adjacent layers. We also propose a new set of physical requirements for the parameters useful in the constrained model tting. We apply this updated MLSI to two sets of Hα and Ca ii line spectral data taken by the Fast Imaging Solar Spectrograph (FISS) from a quiet region and an active region, respectively. We nd that the new version of the MLSI satisfactorily ts most of the observed line proles of various features, including a network feature, an internetwork feature, a mottle feature in a quiet region, and a plage feature, a superpenumbral bril, an umbral feature, and a fast down ow feature in an active region. The MLSI can also yield physically reasonable estimates of hydrogen temperature and nonthermal speed as well as Doppler velocities at different atmospheric levels. We conclude that the MLSI is a very useful tool to analyze the Hα line and the Ca ii 8542 line spectral daya, and will promote the investigation of physical processes occurring in the solar photosphere and chromosphere.

본 실험은 고온기 파프리카 재배에서 CaCl2 엽면 살포에 의한 배꼽썩음과 발생과 경감 효과를 알아보고자 과실 크기에 따른 살포 시기, 횟수 및 시간에 미치는 영향을 구명하였다. CaCl2(Ca 0.4%) 엽면 살포는 6월 3일 부터 7월 1일 까지 방아다리 위 4－9 마디의 착과 과실과 잎에 식물체 1주당 350mL/ 회를 처리하였다. CaCl2를 7일 간격으로 4주간 엽면 살포 후 수확한 파프리카의 Ca 함량은 배꼽썩음과 과실의 과폭 11－ 20mm 처리에서 가장 낮았고, pedicel > stem-end > middle, blossom-end 순으로 낮아졌다. 정상과 과실의 Ca 함량은 과폭 31－40mm 처리에서 뚜렷하게 증가하였고 배꼽썩음과와 비교할 때 78% 높았다. 과폭 21mm 이상의 과실 middle과 blossom-end 부위 Ca 함량은 정상과에서는 19.8%－28.8% 였으며, 배꼽썩음과에서는 15.7%－18.5%였다. 과폭 31－ 40mm 처리에서 배꼽썩음과 발생율은 60% 이상으로 급격히 증가하였다. 과폭 크기별 엽면 살포 처리에 따른 파프리카 과중은 차이가 없었으며, 상품과율은 21－30mm 크기에서 가 장 높았고, 당도는 과폭 11－30mm 처리에서 높았다. 과폭 21 －30mm 파프리카에 7일 동안 CaCl2를 3회 엽면 살포하였을 때 세포벽 결합(cell wall-bound, CWB) Ca 함량은 가장 높았고, 배꼽썩음과 발생율은 6.3%로 가장 낮았다. CaCl2 엽면 살포 처리 10일 후 파프리카의 CWB Ca 함량은 대조구에 비해 모든 처리에서 2.9배－3.5배 증가하였다. 하루 중 1회 시간을 달리하여 CaCl2 엽면 살포하였을 때, 7일째 엽소현상이 오전 9시 30분 처리에서 부터 오후 17시 처리 까지 관찰되었고, proline 함량은 처리 시간이 늦어질수록 증가되었다. 따라서 파프리카 여름재배시 배꼽썩음과 발생 경감을 위한 CaCl2 엽면 살포 방법은 과폭 21－30mm인 시기에 3일 간격으로 2회 －3회, 오전 8시 이전에 살포 하는 것이 적합하리라 본다.

High voltage impulse (HVI) has been gained attention as an alternative technique that could control the CaCO3 scale problems encountered in water main, pipe, cooling tower and heat exchanger vessels. The aim of this study was to investigate the effect of electric field (E) and contact time (t) of HVI on reduction of Ca2+ concentration at two different temperatures of 25℃ and 60℃. A kinetic model on the effect of E and t was investigated too. As the E and t increased, the Ca2+ concentration decreased more than that of the control (= no HVI). The Ca2+ concentration decreased up to 81% at 15 kV/cm at 60℃, which was nearly 2 times greater than the control. With these experimental data-set of reduction of Ca2+ concentration under different E and t, the kinetic model was developed. The relationship between E and t required to reduce the concentration of Ca2+ by 30% was modeled at each temperature. The empirical model equations were; E0.83· t = 60.3 at 25℃ and E0.08· t = 1.1 at 60℃. These equations state the products of En and t is always constant, which means that the required contact time can be reduced in accordance with the increment of E and vice versa.

Near infrared reflectance spectroscopy (NIRS) is routinely used for the determination of nutrient components of forages. However, little is known about the impact of sample preparation and wavelength on the accuracy of the calibration to predict minerals. This study was conducted to assess the effect of sample preparation and wavelength of near infrared spectrum for the improvement of calibration and prediction accuracy of Calcium (Ca) and Phosphorus (P) in imported hay using NIRS. The samples were scanned in reflectance in a monochromator instrument (680–2,500 nm). Calibration models (n = 126) were developed using partial least squares regression (PLS) based on cross-validation. The optimum calibrations were selected based on the highest coefficients of determination in cross validation (R2) and the lowest standard error of cross-validation (SECV). The highest R2 and the lowest SECV were obtained using oven-dry grinded sample preparation and 1,100-2,500 nm wavelength. The calibration (R2) and SECV were 0.99 (SECV: 468.6) for Ca and 0.91 (SECV: 224.7) for P in mg/kg DM on a dry weight, respectively. Results of this experiment showed the possibility of NIRS method to predict mineral (Ca and P) concentration of imported hay in Korea for routine analysis method to evaluate the feed value.

The pH dependence of sorption distribution coefficient (Kd) of Np(IV) on MX-80 in Ca-Na-Cl type solution with the ionic strength of 0.3 M, which was similar to one of the reference groundwaters in crystalline rock, was experimentally investigated under the reducing conditions. The overall trend of Kd on MX-80 was independent of pH at 5 ≤ pH ≤ 10 but increased as pH increased at pH ≤ 5. The 2-site protolysis non-electrostatic surface complexation and cation exchange model was applied to the experimentally measured pH dependence of Kd and the optimized surface complexation constants of Np(IV) sorption on MX-80 were estimated. The values of surface complexation constants in this work agreed relatively well with those in the Na-Ca-Cl solution previously evaluated, suggesting that compared to Na+, the competition of Ca2+ with Np(IV) for surface complexation on MX-80 was not much strong in Ca-Na-Cl solution. The sorption model well predicted the pH dependence of Kd values but slightly overestimated the sorption at the low pH region.

This study explores reducing the oxygen content of a commercial Ti-48Al-2Cr-2Nb powder to less than 400 ppm by deoxidation in the solid state (DOSS) using Ca vapor, and investigates the effect of Ca vapor on the surface chemical state. As the deoxidation temperature increases, the oxygen concentration of the Ti-48Al-2Cr-2Nb powder decreases, achieving a low value of 745 ppm at 1100oC. When the deoxidation time is increased to 2 h, the oxygen concentration decreases to 320pp m at 1100oC, and the oxygen reduction rate is approximately 78% compared to that of the raw material. The deoxidized Ti-48Al-2Cr-2nb powder maintains a spherical shape, but the surface shape changes slightly owing to the reaction of Ca and Al. The oxidation state of Ti and Al on the surface of the Ti-48Al-2Cr-2Nb powder corresponds to a mixture of TiO2 and Al2O3. As a result, the peaks of metallic Ti and Ti suboxide intensify as TiO2 and Al2O3 in the surface oxide layer are reduced by Ca vapor deposition

We investigate the effects of Yb2O3 and calcium aluminosilicate (CAS) glass as sintering additives on the sintering behavior of AlN. The AlN specimens are sintered at temperatures between 1700oC and 1900oC for 2 h in a nitrogen atmosphere. When the Yb2O3 content is low (within 3 wt.%), an isolated shape of secondary phase is observed at the AlN grain boundary. In contrast, when 3 wt.% Yb2O3 and 1 wt.% CAS glass are added, a continuous secondary phase is formed at the AlN grain boundary. The thermal conductivity decreases when the CAS glass is added, but the sintering density does not decrease. In particular, when 10 wt.% Yb2O3 and 1 wt.% CAS glass are added to AlN, the flexural strength is the highest, at 463 MPa. These results are considered to be influenced by changes in the microstructure of the secondary phase of AlN.

NKN [(Na,K)NbO3] is a candidate lead-free piezoelectric material to replace PZT [Pb(Zr,Ti)O3]. A single crystal has excellent piezoelectric-properties and its properties are dependent of the crystal orientation direction. However, it is hard to fabricate a single crystal with stoichiometrically stable composition due to volatilization of sodium during the growth process. To solve this problem, a solid solution composition is designed (Na,K)NbO3-Ba(Cu,Nb)O3 and solid state grain growth is studied for a sizable single crystal. Ceramic powders of (Na,K)NbO3-M(Cu,Nb)O3 (M = Ca, Sr, Ba) are synthesized and grain growth behavior is investigated for different temperatures and times. Average normal grain sizes of individual specimens, which are heat-treated at 1,125 oC for 10 h, are 6.9, 2.8, and 1.6 m for M = Ca, Sr, and Ba, respectively. Depending on M, the distortion of NKN structure can be altered. XRD results show that (NKN-CaCuN: shrunken orthorhombic; NKN-SrCuN: orthorhombic; NKN-BaCuN: cubic). For the sample heat-treated at 1,125 oC for 10 h, the maximum grain sizes of individual specimens are measured as 40, 5, and 4,000 m for M = Ca, Sr, and Ba, respectively. This abnormal grain size is related to the partial melting temperature (NKN-CaCuN: 960 oC; NKN-SrCuN: 971 oC; NKN-BaCuN: 945 oC).

Short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate are secondary metabolites produced by anaerobic fermentation of dietary fibers in the intestine. Intestinal SCFAs exert various beneficial effects on intestinal homeostasis, including energy metabolism, autophagy, cell proliferation, immune reaction, and inflammation, whereas contradictory roles of SCFAs in the oral cavity have been reported. Herein, we found that low and high concentrations of SCFAs induce differential regulation of intracellular Ca2+ mobilization and expression of pro-inflammatory cytokines, such as interleukin (IL)-6 and IL-8, respectively, in gingival fibroblast cells. Additionally, cell viability was found to be differentially regulated in response to low and high concentrations of SCFAs. These findings demonstrate that the physiological functions of SCFAs in various cellular responses are more likely dependent on their local concentration.

Geopolymer is an alumina silicate-based ceramic material that has good heat-resistance and fire-resistance; it can be cured at room temperature, and thus its manufacturing process is simple. Geopolymer can be used as a reinforcement or floor finish for high-speed curing applications. In this manuscript, we investigate a high-speed curing geopolymer achieved by adding calcium to augment the curing rate. Metakaolin is used as the main raw material, and aqueous solutions of KOH and K2SiO3 are used as the activators. As a result of optimizing the high bending strength as a target factor for geopolymers with SiO2 / Al2O3 ratio of 4.1 ~ 4.8, the optimum ranges of the active agent are found to be 0.1 ≤ K2O / SiO2 ≤ 0.4 and 10 ≤ H2O / K2O ≤ 32.5, and the optimum range of the curing accelerator is found to be 0.82 Ca (OH)2 / Al2O3 2.87. The maximum flexural strength is found to be 1.35 MPa at Ca (OH)2 / Al2O3 = 2.82, K2O / SiO2 = 0.3, and H2O / K2O = 11.3. The physical and thermal properties are analyzed to validate the applicability of these materials as industrial insulating parts or repairing·finishing materials in construction.