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(CoxZn1–x)TiNb2O8 (x = 0.2–0.8) microwave dielectric ceramics were synthesized via the conventional solid‐state reaction route, and the correlation of microwave dielectric properties on the crystal structure was discussed. Crystal structures of ceramic samples were systematically investigated by X‐ray powder diffraction. Moreover, composition‐induced phase transitions were confirmed via the following sequence: for x ≤ 0.2, single‐phase orthorhombic ixiolite (ZnTiNb2O8) was formed, whereas for 0.3 ≤ x<0.8, ixiolite and rutile coexisted. When x ≥ 0.8, only single‐phase rutile was detected. For the (CoxZn1–x)TiNb2O8 ceramics, the microwave dielectric properties were changed with the crystal structural transitions: the dielectric constant (εr) and the temperature coefficient of resonant frequency (τf) increased upon increasing the Co2+, but the quality factor (Q) decreased. A near‐zero τf = +1.6 ppm/°C was obtained in the Co0.38Zn0.62TiNb2O8 ceramics with εr = 40.7 and high Q × f = 16 790 GHz. These research outcomes are expected to have great significance for developing microwave dielectric ceramics in practical applications. [ABSTRACT FROM AUTHOR]

Microwave dielectric ceramics are considered to be one of the key materials for dielectric resonators (DR) and have very broad application prospects in the fifth generation (5G) mobile communication system. Here we have prepared high‐quality factor Y3Al5O12 (YAG) transparent dielectric ceramics using high‐purity α‐Al2O3 and Y2O3 powders by cold isostatic pressing of the vacuum sintered with tungsten meshes as the heating elements. Optimum relative permittivity (εr) ~10.53, quality factor Q × f (Q = 1/dielectric loss, f = resonant frequency) ~95, 270 GHz (at =7.37 GHz), and temperature coefficient of resonant frequency (TCF) ~ −51.7 ppm °C−1 were obtained at a sintering temperature of 1780°C for 12 h. For the first time, YAG transparent ceramic dielectric resonator antenna (DRA) is designed as a dominant TE111y mode and a higher‐order TE113y mode using the aperture coupling feeding configuration excitation. The proposed transparent dielectric ceramic DRA can provide a broad impedance bandwidth of 4.193 GHz (ranging from 21.90 to 26.09 GHz) for S11 < −10 dB, radiation efficiency of 92.1%, and compact DR unit. The proposed DRA can be used potentially as a 5G millimeter (mm)‐wave multiple‐input‐multiple‐output (MIMO) antenna unit. [ABSTRACT FROM AUTHOR]

Novel scheelite‐type [Ca0.55(Nd1‐xBix)0.3]MoO4 (0.2 ≤ x ≤ 0.95) ceramics were prepared using the solid‐state reaction method. According to the X‐ray diffraction data, a solid solution was formed in 0.2 ≤ x ≤ 0.95 and all the samples belong to pure scheelite phase with the tetragonal structure. As revealed by Raman spectroscopy, the number of vibrational modes decreased with the increase in x value, which further indicated that Bi3+ ions occupied A‐site of scheelite structure. As the x value increased, the sintering temperature decreased from 740°C to 660°C; the permittivity increased from 12.6 to 20.3; the Qf value first decreased slightly and gradually remained stable. Based on the infrared reflectivity spectrum analysis, the calculated permittivity derived from the fitted data shared the same trend with the measured value. The [Ca0.55(Nd0.05Bi0.95)0.3]MoO4 ceramic sintered at 660 °C attained a near‐zero value temperature coefficient ~τf (−7.1 ppm/°C) and showed excellent microwave dielectric properties with a ɛr ~ 20.3 and a Qf ~ 33 860 GHz, making this system a promising candidate in the ultralow temperature cofired ceramic (ULTCC) technology. [ABSTRACT FROM AUTHOR]

Lung cancer is prone to metastasis to various organs. Although intraocular metastasis (IOM) occurs at a later stage than metastasis to other organs, it often adversely affects the quality of life and suggests a poor prognosis. In this study, we selected 1608 patients with lung cancer who had metastasis to at least one site and explored clinical differences between those with IOM and non‐IOM (NIOM). An independent t test and chi‐squared test were used to analyze the clinical features of the patients. The statistically significant parameters were analyzed by binary logistic regression to determine the risk factors for IOM. A receiver operating characteristic curve was constructed to assess their diagnostic value in IOM. The results showed that no significant differences were noted in age, gender, and pathological type between the IOM and NIOM groups. However, the IOM group had higher levels of alpha‐fetoprotein, carcinoembryonic antigen, cancer antigen (CA)‐125, CA‐153, cytokeratin fragment 19 (CYFRA 21‐1), and total prostate‐specific antigen, compared with the NIOM group. Binary logistic regression indicated that CA‐153 and CYFRA 21‐1 were risk factors for IOM in patients with MLC (P < 0.05). Area under the curve of CA‐153, CYFRA 21‐1 and their combination were 0.791, 0.860, and 0.872 respectively. The cutoff values for CA‐153 and CYFRA 21‐1 were 22.2 U/mL and 6.785 ng/mL. In conclusion, both CA‐153 and CYFRA 21‐1 were independent risk factors for IOM in patients with metastatic lung cancer (MLC), whereas the combination of CA‐153 and CYFRA 21‐1 assessment yields the most value in the detection of IOM in patients with MLC. [ABSTRACT FROM AUTHOR]

In the (Bi1 − xCex)VO4 (0 ≤ x ≤ 1) system, we found that the (Bi1 − xCex)VO4 (0 ≤ x ≤ 0.1) belongs to the monoclinic scheelite phase and the (Bi1 − xCex)VO4 (0.7 ≤ x ≤ 1) belongs to the tetragonal zircon phase, while the (Bi1 − xCex)VO4 (0.1 < x < 0.7) belongs to the mixed phases of both monoclinic scheelite and tetragonal zircon structure. Interestingly, two components with near‐zero temperature coefficient of resonant frequency (TCF) appeared in this system. In our previous work, a near‐zero TCF of ~+15 ppm/°C was obtained in a (Bi0.75Ce0.25)VO4 ceramic with a permittivity (εr) of ~47.9 and a Qf (Q = quality factor = 1/dielectric loss; f = resonant frequency) value of ~18 000 GHz (at 7.6 GHz). Furthermore, in the present work, another temperature‐stable microwave dielectric ceramic was obtained in (Bi0.05Ce0.95)VO4 composition sintered at 950°C and exhibits good microwave dielectric properties with a εr of ~11.9, a Qf of ~22 360 GHz (at 10.6 GHz), and a near‐zero TCF of ~+6.6 ppm/°C. The results indicate that this system might be an interesting candidate for microwave device applications. [ABSTRACT FROM AUTHOR]

Objective: Neuroimaging studies have shown that patients with pain‐related conditions have altered neuronal activity and structural functions. The purpose of this study was to investigate whether patients with classical trigeminal neuralgia (CTN) exhibit changes in corresponding neuronal activity via analysis of neuronal activity regional homogeneity (ReHo). Methods: A total of 28 patients presenting with sore eyes (12 men and 16 women) were matched with 28 healthy controls (12 men and 16 women). All participants underwent functional magnetic resonance imaging (fMRI). This ReHo method was used to assess the consistency of changes in neural activity in various brain regions. The receiver operating characteristic (ROC) curve was applied to differentiate ReHo values of patients with CTN from ReHo values of healthy controls. Pearson's correlation analysis was applied to evaluate the correlation between ReHo values of different brain regions of patients with CTN and clinical manifestations. Results: Compared with healthy controls, patients with CTN were found to have increased ReHo values in the inferior cerebellum bilaterally, right inferior temporal gyrus, right middle occipital gyrus, right fusiform gyrus, right superior frontal gyrus, and right precentral gyrus. ROC curve analysis of each brain region revealed near‐perfect accuracy regarding the area under the curve. However, no correlation between ReHo values and clinical manifestations in patients with CTN was found. Conclusions: CTN is associated with altered neuronal networks in different areas of the brain. ReHo values all possess different degrees of change, implying that CTN has a certain impact on cerebral function. [ABSTRACT FROM AUTHOR]

isolation, structure elucidation and anti-HBV activities of the two new amide alkaloids (I), (II), the two new glycosides longumosides A (III) and B (IV) and seven known compounds [ABSTRACT FROM AUTHOR]