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Herein, multiwalled carbon nanotube (MWCNT)/silicon nitride (Si3N4)/polyaniline (PANI) ternary composites are prepared. The preparation method involves attaching carboxyl groups to acid‐modified MWCNT surfaces and amino groups to Si3N4 surfaces modified using a silane‐coupling agent. Then they are combined to binary composites using the solvent‐thermal method. Finally, the ternary composites are prepared by coating PANI on the surface of MWCNT/Si3N4 composites in situ polymerization. The morphology and structure of these composites are characterized through X‐ray diffraction, Fourier‐transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and X‐ray photoelectron spectroscopy. Results show that the reflection loss at 8.8 GHz reaches −42.57 dB when the feeding ratio of MWCNT:Si3N4:PANI is 3:20:40 and the corresponding effective absorption bandwidth reaches 4.06 GHz when the thickness is 3.5 mm. A conductive network with effective electron leaps is formed among MWCNT, Si3N4, and PANI, which increases the conductive loss of the composites. An abundant number of interfaces have formed in the composite materials and promoted dielectric loss. Multiple loss mechanisms and good impedance matching performance endow MWCNT/Si3N4/PANI with excellent microwave absorption performance, and the incorporation of Si3N4 enables the composites to exhibit satisfactory high‐temperature resistance. Thus, these performances render the composites promising materials to address increasing electromagnetic pollution, particularly at high temperatures. [ABSTRACT FROM AUTHOR]

Background: Several studies have investigated the relationship between serum lactate dehydrogenase-to-albumin ratio (LAR) and the prognosis of cancers. However, no studies have explored the association between serum LAR and the survival of oral cancer (OC). This study was aimed to determine the association of serum LAR with the overall survival (OS) of OC. Methods: One hundred and ninety patients with OC were included in this study between January 2018 and December 2019. Log rank test and Kaplan–Meier method were used to compare the survival rate of OC between the low LAR group and the high LAR group. The association between serum LAR and the survival of OC patients was determined via univariate and multivariate Cox regression analyses. Results: Kaplan-Meier analysis and Log rank test indicated that the OS rate in low LAR group was significantly higher than that in high LAR group (P < 0.05). Univariate cox analysis showed that TNM III-IV stage, serum LDH > 162 U/L, and serum LAR > 3.79 were significantly associated with the OS of OC patients. Multivariate Cox analysis suggested that the TNM III-IV stage (HR, 2.317; 95% CI, 1.423– 3.774, P = 0.001) and serum LAR > 3.79 (HR, 5.138; 95% CI, 2.245– 11.756, P = 0.000) were independently related with poor OS of OC patients. Conclusion: High serum LAR (> 3.79) is an independent predictor of adverse prognosis in OC patients. LAR could be used as a promising marker for predicting the OS of OC patients. [ABSTRACT FROM AUTHOR]

Fe contamination has always been one of the most critical issues in the integrated circuit (IC) industry due to its catastrophic effect on device reliability and electrical characteristics. With complementary metal oxide semiconductor (CMOS) technology scaling down, this issue has been attracting more attention. In this paper, the impact of Fe impurity on the reliability of gate oxide integrity (GOI) in advanced CMOS technology is investigated. Intentional contamination of polysilicon gates was conducted in both boron- and phosphorus-doped devices. Failure analysis of the gate oxide was conducted with high-resolution transmission electron microscopy (HRTEM) and the energy dispersive X-ray (EDX) technique. The experimental results disclose that the properties of PMOS are much more sensitive to Fe contamination than those of NMOS. It is suggested that the reason for the above phenomena is that Fe precipitates at the PMOS gate/oxide interface but dissolves uniformly in the NMOS poly gate due to lower formation energy of the FeB pair (0.65 eV) in PMOS than that of the P4-Fe cluster (3.2 eV) in NMOS. [ABSTRACT FROM AUTHOR]

Objective: The sequelae of pelvic inflammatory disease (SPID) are major causes of secondary infertility. Modified Hongteng Baijiang decoction (MHTBD) has produced positive results in the treatment of patients with chronic pelvic inflammatory disease; however, its role in SPID remains elusive. Therefore, this study clarified the role of MHTBD in SPID pathogenesis. Methods: The main components in MHTBD were analyzed by using liquid chromatography‒mass spectrometry (LC/MS). An SPID rat model was established, and the rats were treated with different doses of MHTBD (0.504 g of raw drug/kg, 1.008 g of raw drug/kg, and 2.016 g of raw drug/kg). Endometrial pinopodes were observed via scanning electron microscopy, endometrial thickness and inflammatory cell infiltration were assessed via HE staining, and the expression of estrogen receptor (ER), progesterone receptor (PR), integrin β3 (ITGB3), and CD31 in the endometrium was detected by using immunohistochemistry. Western blot analysis was used to detect the protein expression of LIF, JAK2, p‐JAK2, STAT3, and p‐STAT3 in the endometrium. Moreover, the changes in the gut microbiota were analyzed via 16S rRNA sequencing. Results: MHTBD improved endometrial receptivity, attenuated endometrial pathologic damage, reduced inflammatory cell infiltration, decreased ER and PR expression in the endometrium, and promoted the expression of LIF, p‐JAK2, and p‐STAT3 in the endometrium (p <.05) in SPID rats. Additionally, MHTBD treatment affected the composition of the gut microbiota in SPID rats. Furthermore, MHTBD attenuated endometrial receptivity and pathological damage in SPID rats by promoting the LIF/JAK2/STAT3 pathway. Conclusion: MHTBD attenuates SPID in rats by promoting the LIF/JAK2/STAT3 pathway and improving the composition of the gut microbiota. MHTBD may be a valuable drug for SPID therapy. [ABSTRACT FROM AUTHOR]

Titanium dioxide/multi-walled carbon nanotubes (TiO2/MWCNTs) are nanocomposites (NCs) prepared via click reaction of TiO2 nanoparticles (TiO2 NPs) with azide groups (TiO2–N3) on the surface and MWCNTs with alkynyl groups (MWCNTs–ALK) on the surface. The phase structure, graphitization degree, structure, elemental composition, the microstructure of TiO2/MWCNTs NCs were characterized by XRD, Raman, IR, XPS and SEM, and their electromagnetic (EM) parameters were determined by the vector network analyser. For TiO2/MWCNTs NCs with click reaction, the minimum reflection loss (RLmin) is up to −47.87 dB at 12.02 GHz, the matching thickness is 2.0 mm, and the bandwidth is lower than −10 dB in the range of 7.7–12.48 GHz. Compared with the physically mixed TiO2/MWCNTs composites, TiO2/MWCNTs NCs prepared by click reaction show more excellent EM absorption properties, which is mainly due to the binding of covalent bonds between the two kinds of materials that lead to the enhancement of interfacial effects, the improvement of impedance matching and the increase of electron migration. [ABSTRACT FROM AUTHOR]

This article provides preliminary validity evidence for the shorter Mandarin version of the Vocabulary Size Test (VST) under the content aspect, technical quality, substantive and generalizability aspect of Messick's (1995) construct validity framework. The shorter version with 177 Chinese university students in three proficiency levels indicates that the test enjoys a high level of validity both from the perspective of classical test theory and item response theory. A one-way ANOVA and detailed statistics of Rasch analyses demonstrate that the test could effectively distinguish learners from different proficiency levels. The first eight levels of the VST generally display an ascending difficulty continuum except that some loan words in the seventh and the eighth level prove to be problematic in assessing Chinese learners' vocabulary size accurately. The generalizability aspect of construct validity is demonstrated in that there is no item bias for learners of the same proficiency group in terms of gender. Compared with the results of other studies either on monolingual or bilingual version, this research attempts to justify the appropriateness of the Mandarin version and calls for cautious applications of the test instrument on Chinese learners.

Fe3O4/SiO2 nanocomposites (NCs) were prepared by the interaction of alkyne-functionalized ferric oxide (Fe3O4-Alk) nanoparticles (NPs) and azide-functionalized silicon dioxide (SiO2-N3) NPs via the click reaction. The morphology and structure of the Fe3O4/SiO2 NCs were investigated using scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and infrared analyses, and the electromagnetic parameters were measured using a vector network analyzer. For the Fe3O4/SiO2 nanocomposites obtained via the click reaction, the minimum reflection loss reached − 37.15 dB at 16.68 GHz and a matching thickness of 5.0 mm, and the bandwidth below − 10 dB ranged from 3.2 to 6.7 GHz and 15.7 to 17.6 GHz. The Fe3O4/SiO2 composites synthesized via the click reaction exhibited better microwave absorption performance than the physically blended sample. This is mainly because Fe3O4 and SiO2 are covalently bonded through the click reaction in the composites, creating multiple heterogeneous interfaces, which enhance dielectric loss and impedance matching. [ABSTRACT FROM AUTHOR]

The growing need for the multiband photodetection of a single scene has promoted the development of both multispectral coupling and broadband detection technologies. Photodetectors operating across the infrared (IR) to terahertz (THz) regions have many applications such as in optical communications, sensing imaging, material identification, and biomedical detection. In this review, we present a comprehensive overview of the latest advances in broadband photodetectors operating in the infrared to terahertz range, highlighting their classification, operating principles, and performance characteristics. We discuss the challenges faced in achieving broadband detection and summarize various strategies employed to extend the spectral response of photodetectors. Lastly, we conclude by outlining future research directions in the field of broadband photodetection, including the utilization of novel materials, artificial microstructure, and integration schemes to overcome current limitations. These innovative methodologies have the potential to achieve high-performance, ultra-broadband photodetectors. [ABSTRACT FROM AUTHOR]

To reduce the complexity of monitoring and management of robots in service, a six-axis robot control system based on digital twin is proposed. Based on 3D printing technology, a six-axis robot is developed. At the same time, the kinematics of the robot is analyzed, and its kinematics model is built using the D-H rule. The forward and reverse kinematics of the robot are solved. Through the two-way data interaction between the model layer and the entity layer, the simulation operation of the robot and the twin synchronous operation of the virtual real robot are realized. Based on the real-time data drive, the key parameters of the robot are monitored, and the health parameter table of the current, voltage, joint vibration, and other parameters of the robot system is established. Based on the idea of comparison of the same kind, the abnormal state detection of the robot is realized through quantitative analysis. Finally, the feasibility of the proposed system is verified by experiments. [ABSTRACT FROM AUTHOR]