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The rapidly ever‐growing wireless communication demands development of low loss, ultralow sintering temperature dielectric ceramics with excellent microwave properties. In this work, fabrication and properties of novel microwave dielectric composite ceramics (1 − x)(Na0.5Bi0.5)MoO4–xBaMoO4 (x = 0.3–0.6), in short as ((1 − x)NBM–xBM), synthesized via solid‐state reaction method with an ultralow sintering temperature is reported. X‐ray diffraction analysis confirms the coexistence of both (Na0.5Bi0.5)MoO4 and BaMoO4 scheelite phases. Scanning electron microscopy analysis demonstrated dense microstructures of ceramics sintered at 650°C and 700°C. The dielectric properties of (1 − x)NBM–xBM (x = 0.3–0.6) ceramic are significantly tailored by incorporation of BaMoO4. With the increase in x from 0.3 to 0.6, the (1 − x)(Na0.5Bi0.5)MoO4–xBaMoO4 displays noticeable change in microwave permittivity εr${\varepsilon }_r$ (varying from 25.4 to 16.6), quality factor (Q×f)$(Q \times f)$ values, and temperature coefficient of frequency (τf)$({\tau }_f)$ (range tunable from +37.6 ppm/°C to −14.2 ppm/°C). The microwave dielectric ceramic, 0.5(Na0.5Bi0.5)MoO4–0.5BaMoO4, has optimum dielectric properties (εr=19.02${\varepsilon }_{\mathrm{r}} = 19.02$, Q×f$Q \times f$ = 15 164 GHz, τf = −0.2 ppm/°C) at sintering temperature of 650°C. The dielectric resonator antenna designed using (1 − x)(Na0.5Bi0.5)MoO4–xBaMoO4 ceramics demonstrated excellent radiation performance at resonance frequency of 5.905 GHz, gain of ∼5.8 dBi and 140 MHz bandwidth, which validates its microwave applications utilization within the field of ultralow temperature cofired ceramics technology. [ABSTRACT FROM AUTHOR]

Early diagnosis is a key to improve the prognosis of renal cell carcinoma (RCC); however, reliable RCC biomarkers are lacking in clinical practice. In this study, we used isobaric tags for relative and absolute quantification-based mass spectrometry to identify salivary proteins as biomarkers for the diagnosis of RCC. The objective of this study is to discover biomarkers from saliva by utilizing high-throughput quantitative proteomics approaches. Saliva proteins from 124 RCC patients and healthy individuals were identified and quantified. RCC putative biomarkers were verified by real-time polymerase chain reaction or enzyme-linked immunosorbent assay in a prevalidation sample set. Seventy-one differentially expressed salivary proteins were identified. Serotransferrin, haptoglobin, KRT9, and S100A9, which in previous studies were found to be most closely related to cancers, were selected as putative RCC biomarkers. Haptoglobin and S100A9 were significantly elevated in RCC compared with healthy control samples, although the expression of serotransferrin and KRT9 did not differ between the groups. Furthermore, receiver operating characteristic curves with a cut-off value of 75.49 ng/mL for S100A9 revealed a sensitivity of 87.10% and a specificity of 91.94% for discriminating RCC patients from healthy individuals. Salivary haptoglobin differentiated RCC patients from healthy controls with a sensitivity of 85.48% and specificity of 80.65% (cut-off value 43.02 µg/mL). These results provide experimental evidence to support S100A9 and haptoglobin as potential novel, noninvasive biomarkers for the diagnosis of RCC.

(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]

Iridium (Ir) single-atom catalysts (SACs) exhibit extraordinary advantages in the oxygen evolution reaction (OER) owing to their unique electronic structure and maximized atom utilization. However, further developments have met with bottlenecks due to the limited catalytic activity derived from the widely adopted adsorbate evolution mechanism (AEM) pathway in Ir SACs for OER. Herein, we report an efficient strategy to improve the intrinsic activity of Ir SACs by anchoring atomic Ir on an oxygen vacancy-modified CoNiO2 support (IrSA-VO-CoNiO2), in which a more advanced lattice oxygen oxidation (LOM) pathway is constructed by activating lattice oxygen to participate in OER. Specifically, the synthesized CoNiO2 support could provide the weak metal–oxygen bond and facilitate the movement and conversion of lattice oxygen. The oxygen vacancies provided abundant active sites for the adsorption of OH* and induced a substantial O 2p characteristic near the Fermi level for activating the lattice oxygen in CoNiO2. Moreover, the introduction of Ir atoms in the oxygen vacancies modulated CoNiO2 results in the significant overlap between the Ir 5d and O 2p bands and constructed a stronger Ir–O covalent bond, which extremely facilitated the transformation from O–O to OO* for boosting the final O2 evolution. Through the above-mentioned results, a more efficient LOM pathway in the single-atom Ir catalyst was constructed, and the as-synthesized IrSA-VO-CoNiO2 displayed outstanding OER performance with 10 mA cm−2 at a low overpotential of 183 mV and a high mass activity of 5 A mg−1 at the overpotential of 300 mV, significantly outperforming the reported catalysts. This work proposes an advanced channel to design efficient electrocatalysts for promising OER applications. [ABSTRACT FROM AUTHOR]

The employment of ultra-low permittivity materials in the configuration of antennas has been demonstrated to augment the antenna bandwidth and diminish signal delay effectively. This study presents three ultra-low permittivity metaphosphate microwave dielectric ceramics (MWDCs). The ALaP 4 O 12 (A = Li, Na, K) metaphosphate ceramics, which all belong to the monoclinic crystal system, exhibit extremely low permittivity (ε r ≈ 5) and excellent quality factor ( Q · f > 10,000 GHz) at a low sintering temperature ( T < 950 °C). Terahertz time-domain spectroscopy indicates that the ε r of ALaP 4 O 12 at terahertz frequencies is comparable to that observed in the microwave band and its value remains stable over an extensive frequency range. Furthermore, the relationship between the crystal structure and the dielectric properties of ALaP 4 O 12 has been analyzed through the lens of chemical bond theory. The highest Q · f value observed for LiLaP 4 O 12 can be attributed to the high chemical bond strength and stability of its crystal structure. The lowest ionic polarizability per unit volume is exhibited by NaLaP 4 O 12 , which results in the lowest pore-corrected permittivity. The thermal expansion of the chemical bonds within KLaP 4 O 12 is considerable, resulting in the highest coefficient of thermal expansion. Finally, the performance of a LiLaP 4 O 12 -based dielectric resonator antenna (DRA) excited by slot-coupled microstrip lines was designed and optimized by using different ceramic radius-to-height (RH) ratios. It was found that when the RH ratio of DRA reached 1.85, both the fundamental mode (HEM 11δ ) and the higher-order mode (HEM 12δ ) of DRA were simultaneously excited. The two modes overlap significantly, resulting in an ultra-wideband (UWB) of 46.8% (bandwidth = 7.93 GHz). Concurrently, the maximum radiation efficiency and gain of the DRA, obtained from the simulation, are 97.9% and 7.92 dBi, respectively. The findings of this study may inform the investigation of ultra-low permittivity phosphorus-based MWDCs and UWB DRAs.

To investigate the prevalence of Helicobacter pylori (H. pylori) infection in adolescents and children in Changhua and to compare the differences between urban and rural areas, we used enzyme immunoassay to detect H. pylori stool antigen for feco-prevalence study. In addition, a questionnaire was designed to obtain demographic and clinical information. Children and adolescents under 18 years of age living in Changhua city and Yung-Chin village were divided into 6 groups respectively, ie. 0-3, 3-6, 6-9, 9-12, 12-15, and 15-18 years. A minimum of 30 persons were investigated in each group. A total of 567 subjects (M/F 295/272) were included in this study. There was no significant difference in H. pylori infection with regard to residential area, gender, education of the mother, occupation of parents, family history of peptic ulcer, and number of family members, except for epigastralgia of the subjects (p=0.001) and education of the father (p=0.039). The overall prevalence was 13.75%. A low prevalence was noted in the group 0-3 years (2.0%). The prevalence increased with age and reached its maximum of 23.8% in the age group of 9-12 years and then declined. The multiple logistic regression analysis revealed that only age (odds ratio (OR)=1.3, 95% confidence interval (C.I.)=1.1-1.5) and epigastralgia (OR=1.71, 95% C.I.=1.0-3.0) were the most important risk factors for H. pylori infection after adjusting for participating gender, place of residence and father's age. The difference in age pattern of H. pylori infection between our results and other studies needs further investigation.