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The attention network test (ANT), developed based on the triple‐network taxonomy by Posner and colleagues, has been widely used to examine the efficacy of alerting, orienting and executive control in clinical and developmental neuroscience studies. Recent research suggests the imperfect reliability of the behavioural ANT and its variants. However, the classical ANT fMRI task's test–retest reliability has received little attention. Moreover, it remains ambiguous whether the attention‐related intrinsic network components, especially the dorsal attention, ventral attention and frontoparietal network, manifest acceptable reliability. The present study approaches these issues by utilizing an openly available ANT fMRI dataset for participants with Parkinson's disease and healthy elderly. The reproducibility of group‐level activations across sessions and participant groups and the test–retest reliability at the individual level were examined at the voxel, region and network levels. The intrinsic network was defined using the Yeo‐Schaefer atlas. Our results reveal three critical facets: (1) the overlapping of the group‐level contrast map between sessions and between participant groups was unsatisfactory; (2) the reliability of alerting, orienting and executive, defined as a contrast between conditions, was worse than estimates of specific conditions. (3) Dorsal attention, ventral attention, visual and somatomotor networks showed acceptable reliability for the congruent and incongruent conditions. Our results suggest that specific condition estimates might be used instead of the contrast map for individual or group‐difference studies. [ABSTRACT FROM AUTHOR]

Environmental changes can trigger endoplasmic reticulum (ER) stress and misfolded protein accumulation, potentially leading to pre-eclampsia (PE). Amyloid-β (Aβ) is a crucial misfolded protein that can overactivate autophagy. Our study assessed the expression of Aβ1−42 and autophagic activity in PE placental tissues and trophoblasts under ER stress. Placental tissues were surgically collected from normal pregnant women (NP) and pregnant women with late-onset PE (LOPE) delivering through cesarean section. The expression levels of Aβ1−42 were detected in both PE and NP placental tissues, as well as in tunicamycin (TM)-induced HTR-8/SVneo cells. Autophagy-related proteins, such as Beclin-1, the ratio of LC3-II to LC3-I, ATG5, and SQSTM1/p62 in the placental tissues and HTR-8/SVneo cells were measured by Western blot. The number and morphology of autophagosomes were observed using transmission electron microscopy (TEM). Potential targets associated with the unfolded protein response (UPR) in the placental tissues of NP and PE cases were screened using PCR Arrays. The misfolded protein was significantly upregulated in the PE group. In both PE placental tissues and TM-induced HTR-8/SVneo cells, not only was Aβ1−42 upregulated, but also Beclin-1, ATG5, and LC3BII/I were significantly increased, accompanied by an increase in autophagosome count, while SQSTM1/P62 was downregulated. A total of 17 differentially expressed genes (DEGs) associated with the UPR were identified, among which elevated calnexin (CANX) was validated in the placenta from both PE and TM-induced HTR-8/SVneo cells. Autophagy is significantly upregulated in PE cases due to ER stress-induced Aβ1−42 accumulation, likely mediated by autophagy-related proteins involved in the UPR. [ABSTRACT FROM AUTHOR]

High-entropy carbides with controlled carbon content have the advantages of high thermal stability and good oxidation resistance, which give them potential for application as high-temperature microwave absorbing materials. In this study, (Co0.2Mo0.2V0.2Nb0.2Ta0.2)Cx high-entropy ceramic (HEC) powders are successfully prepared using a mechanical alloying method. Herein, reduction of the conductive graphite content leads to an increase in the concentration of carbon vacancies and a decrease in conductivity, which coordinates the polarization loss and conductivity loss capabilities. The dielectric loss capacity is enhanced by the combined effect of enhanced polarization loss and weakened conductivity loss. Simultaneously, the saturation magnetization intensity increases with the increase of carbon vacancy concentration, which leads to an enhanced magnetic loss capability. Ultimately, the sample (Co0.2Mo0.2V0.2Nb0.2Ta0.2)C0.8 with good impedance matching and attenuation ability achieves microwave absorption optimization at 293–573 K. The minimum reflection loss of (Co0.2Mo0.2V0.2Nb0.2Ta0.2)C0.8 reaches −57.77 dB (473 K) and the effective absorption bandwidth reaches 3.34 GHz (573 K), covering nearly 80% of the X-band with a thickness of only 2.2 mm. This work provides valuable insights into optimizing the high-temperature microwave absorption performance of high entropy carbides. [ABSTRACT FROM AUTHOR]

To address the increasing demand for high microwave‐absorbing performance, new polarization‐response wave‐absorbing metamaterials are developed herein inspired by the microstructure of locust compound eyes by employing bionics and optimization principles. The materials overcome a common limitation of wave‐absorbing metamaterials, wherein the performance substantially decreases with changes in the polarization mode, enabling the broadband absorption for x and y polarizations. The designed bioinspired materials have various shapes of structural units, triggering a multifrequency point response mechanism that effectively improves the wave‐absorbing performance. Experimental and simulation results show that the designed materials can form different equivalent circuits based on structural and polarization differences, influencing the overall wave‐absorbing performance. They exhibit an effective absorption bandwidth of ≈12 GHz (reflection loss < −10 dB) for x or y polarizations at a thickness of 2 mm. This study provides a typical example for future research on wave‐absorbing metamaterials with polarization‐response characteristics. [ABSTRACT FROM AUTHOR]