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Long-lived nuclear singlet states are widely used in NMR because they have longer lifetime (TS) than conventional longitudinal relaxation time (T1). In this paper, we present a new method to calculate the parameters for preparing long-lived nuclear singlet states, which is applicable to weakly-coupled three-spin systems. It was found that in the same three-spin system, there existed a variety of combination of singlet states with different proportional coefficients. Herein, we prepared two singlet states in an acrylic acid sample. The lifetime of the two states was measured experimentally, which showed significant difference. In addition, the effects of temperature on the singlet state lifetimes of acrylic acid were investigated.

Although an inflammatory microenvironment is required for successful implantation, an inflammatory overreaction is one of the causes of unexplained recurrent pregnancy losses (uRPL). Prostaglandin E2 (PGE2) plays a pivotal role in regulating immune balance during early pregnancy, and it can stimulate inflammatory reactions via prostaglandin E2 receptor 3 (EP3). However, the role of PGE2 receptor signaling in the uRPL remains unknown. We aimed to investigate whether EP3 signaling is involved in the mechanism of uRPL. Via immunohistochemistry we could show that the expression of cyclooxygenase-2, EP3 and G protein alpha inhibitor 1 (Gi1) was enhanced in the decidua of the uRPL group in comparison to the control group in first-trimester placentas. In vitro, we demonstrated that sulprostone (an EP1/EP3 agonist) inhibited the secretion of beta-hCG and progesterone in JEG-3 cells and the secretion of beta-hCG in HTR-8/SVneo cells while it induced the expression of plasminogen activator inhibitor type 1 in JEG-3 cells. In addition, PGE2/sulprostone was able to stimulate the expression of Gi1, phosphorylated-extracellular signal-regulated kinases 1/2 (p-ERK1/2) and p53. L-798,106 (an EP3-specific antagonist) suppressed the expression of EP3 and p-ERK1/2 without affecting the secretion of beta-hCG. Elevated activation of EP3 signaling in first-trimester placentas plays an important role in regulating the inflammatory microenvironment, the hormone secretion of extravillous trophoblasts and the remodeling of extracellular matrix in the fetal-maternal interface. L-798,106 might be a ‘potential therapeutic candidate’ for the treatment of uRPL.

CPMG sequence is widely used to measure crosslink density of rubber. However, the crosslink density obtained by this technique has a strong dependence on the interval times between the pulses in CPMG sequence, and the results measured have only a weak correlation with rubber hardness. To overcome this shortcoming, we proposed in this work to construct a 1H T2 relaxation curve by summing Gaussian-weighted CPMG relaxation curves acquired at by varying the interval time between the pulses in CPMG sequence. Using the multi-echo Gaussian-weighted relaxation curve to calculate the crosslink density gave results that had greatly improved correlation with the rubber hardness. The new method was also fast and efficient, as it took only one-tenth of the experimental time required for the conventional 1H double quantum NMR (1H DQ NMR) experiment.

NMR is a frequently used technique for measuring crosslink density of rubbers. In this work, three commonly used proton NMR methods for measuring crosslink density of rubbers[i.e., 1H double-quantum (DQ) NMR, 1H Hahn echo and 1H CPMG echo] were compared. Different approaches showed different results, and the origin of such discrepancy was discussed. The echo time dependence of the crosslink density measured with the CPMG echo method was studied. The ways to improve theCPMG echo-based measurements are discussed.

All solid state lithium-ion batteries have the advantages of high safety, long cycle life and high energy density, as compared with the conventional lithium-ion batteries, and have been attracting more and more research interest. Solid electrolyte is a crucial component of all solid state lithium-ion batteries, which largely determine the performance of the batteries. In this work, a polymer-lithium-ceramics complex was designed and synthesized. The structure and dynamics of the polymer-ceramic interface was studied with solid-state NMR techniques.

With the development of the Internet, the types and quantities of malware have grown rapidly, and how to identify unknown malware is becoming a new challenge. The traditional malware detection method based on fixed features is becoming more and more difficult. In order to improve detection accuracy and efficiency for mobile terminals, this paper proposed a malware detection method for mobile terminals based on application programming interface (API) call sequence, which was characterized by the API call sequence and used a series of feature preprocessing techniques to remove redundant processing of the API call sequence. Finally, the recurrent neural network method (RNN) was used to build the model and perform detection and verification. Furthermore, this paper constructed a malware detection model based on a two-way recurrent neural network and used the two-way long short-term memory network model (LSTM) to train the data set containing 5986 malware samples and 5065 benign software samples to obtain the final detection model and its parameters. Finally, the feature vector of the APK file to be detected was passed into the model and obtained the detection results. The experimental results indicated that the detection accuracy of this method can reach 93.68%. [ABSTRACT FROM AUTHOR]

Objective To explore the relationship between obstructive sleep apnea (OSA) and male infertility (MI) and evaluate the potential causal effect of OSA on MI through a two-sample Mendelian randomization (MR) analysis. Methods Two-sample MR analysis was conducted using genome-wide association study (GWAS) data, including 25 062 cases of SA, 172 050 cases of snoring, and 313 372 controls, as well as summary data extracted from FinnGen for male infertility (1 271 cases and 119 297 controls). The primary analytical method was the inverse variance-weighted (IVW) approach, supplemented by MR-Egger regression, weighted median, simple mode, and weighted mode to provide additional evidence corroborating the IVW results. Tests for horizontal pleiotropy and heterogeneity were performed to ensure result stability. Results There was no substantial evidence supporting an association between OSA and MI incidence using the IVW method (OR = 1. 617, 95% CI- 0. 823-3. 177, P = 0. 163). The result of MR-Egger, weighted median, simple mode, and weighted mode methods were consistent with the results of the IVW method. Conclusion The large MR analysis indicated that obstructive sleep apnea may not be causally associated with a risk of male infertility. [ABSTRACT FROM AUTHOR]

A groundbreaking photocatalytic nanomaterial, Dy2NdSbO7, was fabricated smoothly using the hydrothermal synthesis technique for the first time. Apart from that, Dy2NdSbO7/Bi2WO6 heterojunction photocatalyst (DBHP) was initially fabricated using the solvothermal fabrication technique. X-ray diffractometer, Fourier-transform infrared spectrometer, Raman spectrometer, UV-visible spectrophotometer, X-ray photoelectron spectrometer, inductively coupled plasma optical emission spectrometer, transmission electron microscope, and X-ray energy dispersive spectroscopy have been applied to evaluate and investigate the thetastructure, morphology, and physicochemical properties of synthesized samples. The results confirmed that the pyrochlore-type crystal structures of Dy2NdSbO7 belonged to the Fd3m space group with the cubic crystal system and the β-pyrochlore-type crystal structures of Bi2WO6 which belonged to the Pca21 space group with orthorhombic crystal system. Under visible light exposure for 155 min (VLP-155min) using DBHP in the capacity of the photocatalytic nanomaterial, the removal efficiency of chlorpyrifos (CPS) saturation reached 100%. Comparison of CPS removal efficiency after VLP-155min revealed that DBHP exhibited higher removal efficiency than Dy2NdSbO7, Bi2WO6, or N-doped TiO2 photocatalyst, with removal efficiency 1.15 times, 1.23 times, or 2.55 times higher, respectively. Furthermore, the oxidizing capability of free radicals was investigated using trapping agents. Results demonstrated that superoxide anions exhibited the strongest oxidative capability, followed by hydroxyl radicals and holes. The results presented in this study lay a robust groundwork for future investigations and advancements in the field of highly efficient heterostructure material. These findings have significant implications for the development of environmental remediation strategies and provide valuable insights into sustainable solutions for addressing CPS contamination. [ABSTRACT FROM AUTHOR]

Implantation consists of a complex process based on coordinated crosstalk between the endometrium and trophoblast. Furthermore, it is known that the microenvironment of this fetal–maternal interface plays an important role in the development of extravillous trophoblast cells. This is mainly due to the fact that tissues mediate embryonic signaling biologicals, among other molecules, prostaglandins. Prostaglandins influence tissue through several cell processes including differentiation, proliferation, and promotion of maternal immune tolerance. The aim of this study is to investigate the potential pathological mechanism of the prostaglandin E2 receptor 4 (EP4) in modulating extravillous trophoblast cells (EVTs) in unexplained recurrent marriage (uRM). Our results indicated that the expression of EP4 in EVTs was decreased in women experiencing uRM. Furthermore, silencing of EP4 showed an inhibition of the proliferation and induced apoptosis in vitro. In addition, our results demonstrated reductions in β- human chorionic gonadotropin (hCG), progesterone, and interleukin (IL)-6, which is likely a result from the activation of the cyclic adenosine monophosphate (cAMP)- cAMP-dependent protein kinase A (PKA)-phosphorylating CREB (pCREB) pathway. Our data might provide insight into the mechanisms of EP4 linked to trophoblast function. These findings help build a more comprehensive understanding of the effects of EP4 on the trophoblast at the fetal–maternal interface in the first trimester of pregnancy.

An unprecedented photocatalyst, Sm2EuSbO7, was successfully fabricated in this paper, through a high-temperature solid-state calcination method, which represented its first ever synthesis. Additionally, using the solvothermal method, the Sm2EuSbO7/ZnBiSbO5 heterojunction photocatalyst (SZHP) was fabricated, marking its debut in this study. XRD analysis confirmed that both Sm2EuSbO7 and ZnBiSbO5 exhibited pyrochlore-type crystal structures with a cubic lattice, belonging to the Fd3m space group. The crystal cell parameter was determined to be 10.5682 Å or 10.2943 Å for Sm2EuSbO7 or ZnBiSbO5, respectively. The band gap width measured for Sm2EuSbO7 or ZnBiSbO5 was 2.73 eV or 2.61 eV, respectively. Under visible light irradiation for 150 min (VLTI-150 min), SZHP exhibited remarkable photocatalytic activity, achieving 100% removal of parathion methyl (PM) concentration and 99.45% removal of total organic carbon (TOC) concentration. The kinetic constant (k) for PM degradation and visible light illumination treatment was determined to be 0.0206 min−1, with a similar constant k of 0.0202 min−1 observed for TOC degradation. Remarkably, SZHP exhibited superior PM removal rates compared with Sm2EuSbO7, ZnBiSbO5, or N-doped TiO2 photocatalyst, accompanied by removal rates 1.09 times, 1.20 times, or 2.38 times higher, respectively. Furthermore, the study investigated the oxidizing capability of free radicals through the use of trapping agents. The results showed that hydroxyl radicals had the strongest oxidative capability, followed by superoxide anions and holes. These findings provide a solid scientific foundation for future research and development of efficient heterojunction compound catalysts. [ABSTRACT FROM AUTHOR]

A high-linearity directly-modulated analog photonic link (APL) with simultaneous suppression of the even-order intermodulation distortion, third-order intermodulation distortion (IMD3), and cross-modulation distortion (XMD) is proposed and experimentally demonstrated by the corporation of push-pull structure and an adaptive compensation algorithm. In the proposed directly-modulated APL system, the push-pull structure is introduced to effectively eliminate all the even-order nonlinear distortions, including the second-order intermodulation distortion and the second-order harmonic distortions. To further simultaneously suppress the IMD3 and XMD, an adaptive compensation algorithm is designed and adopted at the receiver. The experimental results show that the second-order spurious-free dynamic range and the third-order spurious-free dynamic range is improved by 19.8 and 12.4 dB, respectively, corresponding to 7.15% error vector magnitude performance improvement for a 120 Mb/s 64QAM-OFDM RF signal transmission when the input RF power is 13 dBm.

An extension of the conventional dual Schottky diode-based predistortion circuit (PDC) is proposed to linearize directly modulated radio over fiber (RoF) system. The main advantages of the proposed PDC are simple configuration, excellent distortion suppression, and broad bandwidth from dc to 6 GHz. By using the proposed cascaded Schottky diodes-based PDC, the condition of third-order intermodulation nonlinearities suppression can be more easily satisfied and the optimal linearization effect can be achieved due to the fact that it has more circuit adjustment parameters. The experimental results show that by using the proposed PDC, the spurious-free dynamic range (SFDR) @2 GHz of the optical transceiver which is designed by ourselves can be improved from 93.8 dB·Hz2/3 to 112.1 dB·Hz4/5 in a 1-Hz bandwidth, corresponding to 7.21% error vector magnitude performance improvement for 20 MHz 64QAM-OFDM @2 GHz signal transmission over 10 km standard single mode fiber. The linearity improvement by using the proposed PDC has also been verified in a commercial optical transceiver based RoF system, and the achieved SFDR @ 2 GHz can be increased from 102.8 dB·Hz2/3 to 121.6 dB·Hz4/5 in a 1-Hz bandwidth.

Cognitive impairment in Alzheimer’s disease (AD) is usually accompanied by synaptic loss in both the hippocampus and neocortex. In the early stage of AD, amyloid β-induced synapse changes is the main reason, while in the later stage, the accumulation of Tau protein promotes synapse degeneration as the key factor leading to dementia. MicroRNA (miRNA) is closely related to the expression changes of many AD-related genes. One of the most abundant brain-enriched miRNAs is miR-132, which has been shown to regulate both neuron morphogenesis and plasticity. It has been reported that miR-132 is significantly reduced in the brains of Alzheimer’s patients. Genetic deletion of miR-132 in mice promotes Aβ deposition, leading to impaired memory and enhanced Tau pathology, but how the miRNA-mediated gene expression dysregulation contributes to AD pathology remains unclear. Here we found the possible downstream target of miR-132 by in silico analysis, namely C1q. C1q is the primary protein of classical complement cascade, which is highly expressed in the synaptic regions of the central nervous system in Alzheimer’s patients. However, it is not clear whether miR-132 plays a role in AD through regulating C1q. To address this question, the APP/PS1 transgenic mice were transfected with miR-132 and given C1 inhibitors. Behavior tests were conducted to assess memory and cognitive abilities seven days after administration. In addition, we analyzed the expression of PSD95, Synapsin-1 and phosphorylated (p)-Synapsin. We found that the expression levels of the synaptic proteins treated with miR-132 or C1INH were significantly increased compared with the AD group. Further RT-qPCR result suggested that miR-132 might regulate C1q expression in AD.