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The surface of nano-silicon dioxide (nano-SiO2) particles was modified by small molecular coupling agent KH-560 and macromolecular coupling agent SEA-171, respectively, to change the surface activity and structure. The modified nano-SiO2 was then used for reinforcing cyanate ester resin (CE). Influences of the content of nano-SiO2 and the interfacial structure over the thermal and frictional properties of nano-SiO2/CE composites were investigated. The mechanism of the surface modification of silicon dioxide by KH-560 and SEA-171 was discussed. The experimental results show that the addition of coupling agents increased the interfacial bonding between nano-SiO2 particles and the CE resin so that the heat resistance and friction properties of the composites were improved. After surface treatment of nano-SiO2 by SEA-171, the thermal decomposition temperature of the 3.0 wt% nano-SiO2/CE composites increased nearly by 75 °C and the frictional coefficient was reduced by 25% compared with that of the pure CE, and the wear resistance increased by 77%. Keywords: Cyanate ester resin, Silicon dioxide, Silane coupling agent, Frictional properties

Purpose: The signals of glutamate (Glu) and glutamine (Gln) are often significantly overlapped in routine 1H‐MR spectra of human brain in vivo. Selectively probing the signals of Glu and Gln in vivo is very important for the study of the metabolisms in which Glu and Gln are involved. Methods: The Glu−/Gln‐ targeted pulse sequences are developed to selectively probe the signals of Glu and Gln. The core part of the Glu−/Gln‐ targeted pulse sequences lies on the preparation of the nuclear spin singlet orders (SSOs) of the five‐spin systems of Glu and Gln. The optimal control method is used to prepare the SSOs of Glu and Gln with high efficiency. Results: The Glu−/Gln‐ targeted pulse sequences have been applied on phantoms to selectively probe the signals of Glu and Gln. Moreover, in the in vivo experiments, the signals of Glu and Gln in human brains of healthy subjects have been successfully probed separately. Conclusion: The developed Glu−/Gln‐ targeted pulse sequences can be used to distinguish the 1H‐MR signals of Glu and Gln in human brains in vivo. The optimal control method provides an effective way to prepare the SSO of a specific spin system with high efficiency and in turn selectively probe the signals of a targeted molecule. [ABSTRACT FROM AUTHOR]

In order to find and develop new botanical pesticides against storage pests, components of the essential oil (EO) from Zanthoxylum bungeanum were identified by GC-MS and their insecticidal activity against the stored product pests were studied. The EO was obtained by steam distillation. Results showed that EO was rich in limonene (23.67), linalool (21.76) and linalyl anthranilate (10.87). In contact assays, linalool exhibited strongest toxicity to red flour beetle adult (LD50 = 17.06 μg/adult) and larvae (LD50 = 16.42 μg/larvae), and linalool was the most active one against the Lasioderma serricorne (LD50 = 15.36 μg/larvae). Then limonene and linalool showed different levels of fumigant activities against the two insect species. Synergism effect existed in the proportion of contact assays against Tribolium castaneum adults, and additive was observed in the proportion of 7:1 against T. castaneum larvae. This work provides important information for the development and utilization of Z. bungeanum and suggests that the EO of Z. bungeanum has the potential to serve as bio-insecticides for controlling pest damage in stored products. [ABSTRACT FROM AUTHOR]

Background: The pathophysiological changes in the remote myocardium after acute myocardial infarction (MI) remains less understood. Purpose To assess the inflammation in the remote myocardium post‐MI and its association with left ventricular (LV) remodeling using T2 mapping. Study type: Prospective. Animal Model and Subjects: Twelve pigs at 3‐day post‐MI, 6 pigs at 3‐month post‐MI, 6 healthy pigs; 54 patients at 3‐day and 3‐month post‐MI, 31 healthy volunteers; Field Strength/Sequence: A 3 T MRI/ steady‐state free‐precession sequence for T2 mapping (animals: 0, 30, and 55 msec; human: 0, 25, and 55 msec), phase‐sensitive inversion recovery gradient echo for late gadolinium enhancement (LGE), balanced steady free‐precession sequence for cine. Assessment Infarcted myocardium was defined on LGE, remote T2 was measured on T2 maps. LV remodeling was evaluated as LV end‐diastolic volume change index between two scans using cine. CD68 staining was conducted to detect monocyte/macrophage. Statistical Tests: Student‐t test and one‐way ANOVA were used to compare remote T2 with normal controls. The association of remote T2 with LV remodeling was assessed using linear regression. P values of <0.05 were used to denote statistical significance. Results: Compared with healthy pigs, remote T2 significantly increased from 3 days to 3 months post‐MI (31.43 ± 0.67 vs. 33.53 ± 1.15 vs. 36.43 ± 1.07 msec). CD68 staining demonstrated the inflammation in remote myocardium post‐MI but not in healthy pigs. Significant remote myocardial alterations in T2 were also observed in human group (40.51 ± 1.79 vs. 41.94 ± 1.14 vs. 42.52 ± 1.71 msec). In patients, the 3‐month remote T2 (β = 0.432) and remote T2 variation between two scans (β = 0.554) were both independently associated with LV remodeling. Conclusion: T2 mapping could characterize the abnormalities in the remote myocardium post‐MI, which was potentially caused by the inflammatory response. Moreover, variations in remote T2 were associated with LV remodeling. Evidence Level 1 Technical Efficacy: Stage 3 [ABSTRACT FROM AUTHOR]

This study presents a novel approach to design the single‐feed circularly polarized (CP) microstrip antenna by the periodic fractal parasitic structure (PFPS). By adding the PFPS along the radiated patch, a new independent orthogonal mode is generated. When the magnitudes of these two modes are the same and the time‐phase difference between them is 90°, the antenna can realise CP radiation. Parameter studies of the PFPS show how to design the CP microstrip antenna. The proposed CP microstrip antenna, designed for the satellite navigation system, has a 30 MHz 10‐dB impedance bandwidth and an 8 MHz 3‐dB axial ratio bandwidth in the centre frequency of 1.575 GHz. The advantage of this presented CP antenna is that these two modes for realising the CP radiation are independent of each other. This makes it more convenient to simplify the designing and debugging of the proposed CP antenna. [ABSTRACT FROM AUTHOR]

This paper deals with the adaptive reliable \boldsymbol H\infty optimization control problem for linear time-delayed systems (LTDSs) against time-varying actuator faults. A novel delay-dependent adaptive \boldsymbol H\infty performance index is described for LTDSs. An exponential function term has been successfully introduced to establish a novel actuator fault parameters estimation scheme. Moreover, the designed indirect adaptive controller includes both offline and online gains, which can be obtained by robust optimization technique and adaptive fault parameters estimation, respectively. By employing an improved Lyapunov–Krasovskii functional and applying some new-developed integral inequalities technique, some delay-dependent sufficient conditions with less conservatism are established to make the closed-loop systems exponentially stable and have the optimized adaptive delay-dependent \boldsymbol H\infty performance index. Finally, the effectiveness and superiority of the presented scheme are demonstrated by two examples. [ABSTRACT FROM AUTHOR]

Four compounds, namely, [Zn(H2L)2 ·4H2O] ( 1), [Cu(HL) ·(H2O)] ·H2O ( 2), [Ni3L2(bpy)2 ·12H2O] ·4H2O ( 3), and [Co3L2(bpy)2 ·12H2O] ·4H2O ( 4) [H3L = 4, 4′-[(5-carboxy-1, 3-phenylene)bis(oxy)]dibenzoic acid], were synthesized under solvothermal conditions by employing a semi-rigid aromatic multi-carboxylic acid ligand (H3L) and ancillary nitrogen ligand (bpy = 4, 4′-bipyridine). X-ray diffraction studies revealed that complexes 1, 3, and 4 show zero-dimensional (0D) structures, which were further extended to distinct 3D supramolecular nets by extensive hydrogen-bond interactions. However, in compound 2, 1D chains of square-shaped pores were linked together by HL2- ligands to generate a 2D porous layer along the ac plane. Comparison of the structures indicated that not only the conformation of the functional ligand, but also the ancillary ligand helped in structural determination of the compounds. Compound 1 exhibited solid fluorescence emission originating from an intraligand π→π* transition. Magnetic susceptibility measurements demonstrated that compound 2 exhibited antiferromagnetic coupling between adjacent copper(II) ions, with the corresponding J values of -141.84 cm-1. Furthermore, the thermal behaviors of the complexes 1- 4 were studied by thermogravimetric analysis. [ABSTRACT FROM AUTHOR]

Investigations have indicated that storage pests pose a great threat to global food security by damaging food crops and other food products derived from plants. Essential oils are proven to have significant effects on a large number of stored grain insects. This study evaluated the contact toxicity and fumigant activity of the essential oil extract from the aerial parts of Elsholtzia ciliata and its two major biochemical components against adults and larvae of the food storage pest beetle Tribolium castaneum. Gas chromatography–mass spectrometry analysis revealed 16 different components derived from the essential oil of E. ciliata, which included carvone (31.63%), limonene (22.05%), and α-caryophyllene (15.47%). Contact toxicity assay showed that the essential oil extract exhibited a microgram-level of killing activity against T. castaneum adults (lethal dose 50 (LD50) = 7.79 μg/adult) and larvae (LD50 = 24.87 μg/larva). Fumigant toxicity assay showed LD50 of 11.61 mg/L air for adults and 8.73 mg/L air for larvae. Carvone and limonene also exhibited various levels of bioactivity. A binary mixture (2:6) of carvone and limonene displayed obvious contact toxicity against T. castaneum adults (LD50 = 10.84 μg/adult) and larvae (LD50 = 30.62 μg/larva). Furthermore, carvone and limonene exhibited synergistic fumigant activity against T. castaneum larvae at a 1:7 ratio. Altogether, our results suggest that E. ciliata essential oil and its two monomers have a potential application value to eliminate T. castaneum. [ABSTRACT FROM AUTHOR]

In this study, we optimal the ultrasound-assisted ionic liquid extraction (UAILE) process of polysaccharides from Crataegus songarica K. Koch fruits. The optimal conditions determined were ultrasonic power of 400 W, temperature of 79°C, extraction time of 78 min, ethylammonium dodecyl sulfate (EADS) concentration of 1.52 mg/mL, and liquid-solid ratio of 51:1 mL/g. Under these conditions, the polysaccharides yield was 34.37%, which was significantly higher than that obtained by the conventional ultrasound-assisted extraction (UAE) and hot water extraction (HWE) methods. After purification, we studied the chemical composition, physicochemical properties, and structural characteristics of polysaccharides (CSP). The results showed that CSP is a heteropolysaccharide containing α-linkage glucopyranose, which is mainly composed of mannose, arabinose, galactose, and glucose, with a molecular weight (Mw) of 27.82 × 10 4  Da. In addition, CSP demonstrated significant free radical scavenging ability and was able to efficiently reduce the H 2 O 2 -induced HepG2 cellular malondialdehyde (MDA) content, while enhancing superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities, showing its superior antioxidant activity. On the basis of these properties, CSP is expected to be used as a novel efficacy factor in the food and pharmaceutical industries., (© 2025 Wiley‐VHCA AG, Zurich, Switzerland.)

Purpose: The signals of glutamate (Glu) and glutamine (Gln) are often significantly overlapped in routine 1 H-MR spectra of human brain in vivo. Selectively probing the signals of Glu and Gln in vivo is very important for the study of the metabolisms in which Glu and Gln are involved., Methods: The Glu-/Gln- targeted pulse sequences are developed to selectively probe the signals of Glu and Gln. The core part of the Glu-/Gln- targeted pulse sequences lies on the preparation of the nuclear spin singlet orders (SSOs) of the five-spin systems of Glu and Gln. The optimal control method is used to prepare the SSOs of Glu and Gln with high efficiency., Results: The Glu-/Gln- targeted pulse sequences have been applied on phantoms to selectively probe the signals of Glu and Gln. Moreover, in the in vivo experiments, the signals of Glu and Gln in human brains of healthy subjects have been successfully probed separately., Conclusion: The developed Glu-/Gln- targeted pulse sequences can be used to distinguish the 1 H-MR signals of Glu and Gln in human brains in vivo. The optimal control method provides an effective way to prepare the SSO of a specific spin system with high efficiency and in turn selectively probe the signals of a targeted molecule., (© 2022 International Society for Magnetic Resonance in Medicine.)

The chemical constituents of the essential oil extracted from Artemisia anethoides and the bioactivities of essential oil against Tribolium castaneum and Lasioderma serricorne were investigated. The main components of the essential oil were 1,8-cineole (36.54%), 2-isopropyl-5-methyl-3-cyclohexen-1-one (10.40%), terpinen-4-ol (8.58%), 2-isopropyltoluene (6.20) and pinocarveol (5.08%). The essential oil of A. anethoides possessed contact and fumigant toxicities against T. castaneum adults (LD 50 = 28.80 μg/adult and LC 50 = 13.05 mg/L air, respectively) and against L. serricorne (LD 50 = 24.03 μg/adult and LD 50 = 8.04 mg/L air, respectively). The crude oil showed repellent activity against T. castaneum and L. serricorne. Especially, the percentage repellency of essential oil was same level with DEET (positive control) against T. castaneum. The results indicated that the essential oil of A. anethoides had the potential to be developed as insecticide and repellent for control of T. castaneum and L. serricorne.

This study was designed to explore the regulatory effects of male germ cell secreting factor NODAL on Sertoli cell fate decisions from obstructive azoospermia (OA) and nonobstructive azoospermia (NOA) patients. Human Sertoli cells and male germ cells were isolated using two-step enzymatic digestion and SATPUT from testes of azoospermia patients. Expression of NODAL and its multiple receptors in human Sertoli cells and male germ cells were characterized by reverse transcription-polymerase chain reaction (RT-PCR) and immunochemistry. Human recombinant NODAL and its receptor inhibitor SB431542 were employed to probe their effect on the proliferation of Sertoli cells using the CCK-8 assay. Quantitative PCR and Western blots were utilized to assess the expression of Sertoli cell functional genes and proteins. NODAL was found to be expressed in male germ cells but not in Sertoli cells, whereas its receptors ALK4, ALK7, and ACTR-IIB were detected in Sertoli cells and germ cells, suggesting that NODAL plays a regulatory role in Sertoli cells and germ cells via a paracrine and autocrine pathway, respectively. Human recombinant NODAL could promote the proliferation of human Sertoli cells. The expression of cell cycle regulators, including CYCLIN A, CYCLIN D1 and CYCLIN E, was not remarkably affected by NODAL signaling. NODAL enhanced the expression of essential growth factors, including GDNF, SCF, and BMP4, whereas SB431542 decreased their levels. There was not homogeneity of genes changes by NODAL treatment in Sertoli cells from OA and Sertoli cell-only syndrome (SCO) patients. Collectively, this study demonstrates that NODAL produced by human male germ cells regulates proliferation and numerous gene expression of Sertoli cells.