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Spermidine is important for the hypothalamic control of pituitary secretion of hormones involved in neuroendocrine functions in mammals. In this study, the effect of exogenous spermidine on the expression of genes and proteins related to polyamine metabolism and polyamine levels was examined. The results indicated that treatment with spermidine at 0.05 mg/g (BW) significantly increased the levels of Oaz1 mRNA and protein expression and decreased putrescine content in mouse hypothalamus (p < 0.05). The administration with spermidine at 0.10 mg/g significantly increased the levels of Oaz1, Oaz2, and Odc expression in mouse hypothalamus (p < 0.05). Treatment with spermidine at 0.05 mg/g significantly increased the levels of Ssat mRNA expression and reduced the level of Smo mRNA expression in mouse hypothalamus (p < 0.05). Putrescine concentrations in the hypothalamus after the administration of spermidine at 0.10 and 0.15 mg/g were significantly higher than those in the control group (p < 0.05). The concentration of both spermidine and spermine in the hypothalamus after the administration of spermidine at 0.15 mg/g was decreased significantly (p < 0.05). In summary, our results indicate that exogenous spermidine affects polyamine homeostasis in the mouse hypothalamus by modulating the expression of genes and proteins related to polyamine metabolism. [ABSTRACT FROM AUTHOR]

Anaerobic digestion (AD) is regarded as an effective treatment to stabilize organic materials and recycle the energy in pig manure. In this study, 0%, 3%, 5%, and 7% biochar (based on dry weight) were added to pig manure to investigate its influence on improving biogas production and reducing heavy metal bioavailability. The potential ecological risk of heavy metals (namely Mn, Zn, Cu, Ni, As, Cd, Pb, and Cr) in digestates was also assessed. Results show that the methane yield was significantly (P < 0.05) increased by 26.7%, 23.0%, and 26.4% following addition of 3%, 5%, and 7% biochar, respectively. Moreover, there was a significant change in the heavy metal speciation in amendment each group. The 5% biochar group showed the highest passivation rate of Ni, As, and Pb, while the highest passivation rate of Cd, Cr, Mn, and Zn was observed with 7% biochar. Although the anaerobic digestion process slightly increased the ecological risk of heavy metals, all tested digestates were still classified as a moderate risk. Results of this study can provide a reference for the treatment of heavy metal pollution in large- and medium-sized anaerobic digesters treating pig manure. [ABSTRACT FROM AUTHOR]

The magneto–mechanical coupling effect and magnetic anisotropy of Fe10Co90 (FeCo) films deposited on silicon wafer (Si), flexible polyethylene terephthalate (PET), freestanding polydimethylsiloxane (PDMS), and pre-stretched 20% PDMS substrates were studied in detail. The loop squareness ratio Mr/Ms and the coercive Hc of the FeCo film grown on a PET substrate can be obviously tuned by applying a small tensile-bending strain, and those of the FeCo film grown on a freestanding PDMS substrate can only be slightly changed when applying a relatively large tensile bending strain. For the FeCo film prepared on a 20% pre-stretched PDMS, a wrinkled morphology is obtained after removing the pre-strain. The wrinkled FeCo film can keep the magnetic properties unchanged when applying a relatively large tensile bending strain perpendicular to the wrinkles. This reveals that PDMS is an ideal substrate for magnetic films to realize flexible immutability. Our results may help for developing flexible magnetic devices. [ABSTRACT FROM AUTHOR]

Magnetic anisotropy is a fundamental key parameter of magnetic materials that determines their applications. For ferromagnetic materials, the magnetic anisotropy can be easily detected by using conventional magnetic characterization techniques. However, due to the magnetic compensated structure in antiferromagnetic materials, synchrotron measurements, such as X-ray magnetic linear dichroism, are often needed to probe their magnetic properties. In this work, we observed an imprinted fourfold magnetic anisotropy in the amorphous ferromagnetic layer of FeRh/CoFeB heterostructures. The MOKE and ferromagnetic resonance measurements show that the easy magnetization axes of the CoFeB layer are along the FeRh〈110〉 and FeRh〈100〉 directions for the epitaxially grown FeRh layer in the antiferromagnetic and ferromagnetic states, respectively. The combined Monte Carlo simulation and first-principles calculation indicate that the fourfold magnetic anisotropy of the amorphous CoFeB layer is imprinted due to the interfacial exchange coupling between the CoFeB and FeRh moments from the magnetocrystalline anisotropy of the epitaxial FeRh layer. This observation of imprinting the magnetocrystalline anisotropy of antiferromagnetic materials on easily detected ferromagnetic materials may be applied to probe the magnetic structures of antiferromagnetic materials without using synchrotron methods. Nanomagnets: Good impressions avoid need for X-rays Capturing magnetic structural information using nanoscale thin films can make it easier to spot materials that exploit the spin properties of electrons for use in spintronics devices. Most magnets have their electron spins aligned in one direction, but antiferromagnets have alternating up/down spins that are useful for sensors. Qingfeng Zhan from East China Normal University in Shanghai and Run-Wei Li at the Chinese Academy of Sciences in Ningbo and colleagues now report a method that identifies antiferromagnets without the use of high-powered X-ray equipment. The team demonstrated that alloys with amorphous crystal structures can convert into ordered frameworks with distinct spin patterns after being thinly coated onto an antiferromagnet's surface. Using a combination of magnetometermicroscopy and computer simulations, the researchers showed that the antiferromagnet imprinted its magnetic ordering onto the alloy through quantum mechanical coupling effects. An imprinted four-fold magnetic anisotropy was observed in the amorphous ferromagnetic layer of FeRh/CoFeB heterostructures. The easy magnetization axes of the CoFeB layer are along the FeRh〈110〉 and FeRh〈100〉 directions for the epitaxially grown FeRh layer in the antiferromagnetic and ferromagnetic states, respectively. The fourfold magnetic anisotropy of the amorphous CoFeB layer is imprinted due to the interfacial exchange coupling between the CoFeB and FeRh moments from the magnetocrystalline anisotropy of the epitaxial FeRh layer, which may be applied to probe the magnetic structures of antiferromagnetic materials without using synchrotron methods. [ABSTRACT FROM AUTHOR]

The MoS2/Ag/AgBr composite with ultrathin-MoS2 layers was prepared by the methods of ultrasonic liquid exfoliation and ion exchange. The composition and micromorphology of ultrathin-MoS2/Ag/AgBr were detected by XRD, EDS, SEM and TEM in detail. The element mapping showed that the samples were well-distributed. The MoS2 in samples and the number of plies were detected by Raman spectra specifically. The results indicated that the photocatalytic performance of the as-prepared samples would increase by 50% when the average thickness of MoS2 was about 4 nm. The enhanced photocatalytic performance of ultrathin-MoS2/Ag/AgBr composite is attributed to the modified conduction band of MoS2 by reducing the layers of MoS2 to fit the potential of O2/O2·−. In particular, this work would expand the scope of application of MoS2 in photodegradation. [ABSTRACT FROM AUTHOR]

Myocarditis is a common disease of the pediatric circulatory system, and its clinical manifestations are diversified. Especially in older patients, chest tightness, shortness of breath and palpitations may occur. However, some patients may have no distinct clinical symptoms and may occasionally experience symptoms during the diagnosis and treatment of respiratory infections, such as arrhythmias in infants and young patients. Because the clinical manifestations of myocarditis are not typical, the specificity and sensitivity of serum myocardial enzyme detection are not very high, which hinders a definitive diagnosis of certain cases by clinicians. However, degeneration, necrosis and inflammatory diseases of cardiomyocytes can affect myocardial conductivity and stress. In patients with myocarditis, an electrocardiogram (ECG) signal changes abnormally; thus, the ECG remains an indispensable means of diagnosing myocarditis. Biomedical signal detection and signal processing techniques can facilitate the study of biological and physiological systems and assist physicians in the diagnosis and treatment of patients. However, traditional manual analysis of ECG methods has some drawbacks. Due to the extensive variety of electrocardiograms, variations in various waveform patterns are subtle and complex. Clinicians often need a solid theoretical foundation and a wealth of clinical experience to make a correct assessment using an ECG. If the medical expert is engaged in a large number of ECG recognition studies for a long time, fatigue may develop and cause misdiagnosis. In addition, the manual analysis of an ECG is part of the postmortem analysis, achieving a real-time diagnosis is difficult, and the resulting delay is likely to cause critical patients to miss the best treatment opportunity. To solve this problem, we have developed a dynamic electrocardiogram medical-assisted diagnosis system to assist medical experts in the diagnosis and treatment of patients with myocarditis. Our system can process the collected ECG signals, obtain waveform parameters, and automatically perform an analysis according to an expert's clinical experience. These parameters provide diagnostic recommendations. [ABSTRACT FROM AUTHOR]

Two 42-metal lanthanide coordination nanorings [Ln42L14(OH)28(OAc)84] (Ln = Nd (1), La (2)) were prepared using a vanillin type ligand. The Nd42 cluster exhibits interesting NIR luminescence sensing behavior to metal ions and nitro explosives. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the feasibility of MRI nerve-bone fusion imaging in assessing the relationship between inferior alveolar nerve (IAN) / mandibular canal (MC) and mandibular third molar (MTM) compared with MRI-CBCT fusion. Materials and methods: The MRI nerve-bone fusion and MRI-CBCT fusion imaging were performed in 20 subjects with 37 MTMs. The Hausdorff distance (HD) value and dice similarity coefficient (DSC) was calculated. The relationship between IAN/MC and MTM roots, inflammatory, and fusion patterns were compared between these two fused images. The reliability was assessed using a weighted κ statistic. Results: The mean HD and DSC ranged from 0.62 ~ 1.35 and 0.83 ~ 0.88 for MRI nerve-bone fusion, 0.98 ~ 1.50 and 0.76 ~ 0.83 for MRI-CBCT fusion. MR nerve-bone fusion had considerable reproducibility compared to MRI-CBCT fusion in relation classification (MR nerve-bone fusion κ = 0.694, MRI-CBCT fusion κ = 0.644), direct contact (MR nerve-bone fusion κ = 0.729, MRI-CBCT fusion κ = 0.720), and moderate to good agreement for inflammation detection (MR nerve-bone fusion κ = 0.603, MRI-CBCT fusion κ = 0.532, average). The MR nerve-bone fusion imaging showed a lower ratio of larger pattern compared to MR-CBCT fusion (16.2% VS 27.3% in the molar region, and 2.7% VS 5.4% in the retromolar region). And the average time spent on MR nerve-bone fusion and MRI-CBCT fusion was 1 min and 3 min, respectively. Conclusions: Both MR nerve-bone fusion and MRI-CBCT fusion exhibited good consistency in evaluating the spatial relationship between IAN/MC and MTM, fusion effect, and inflammation detection. Clinical relevance: MR nerve-bone fusion imaging can be a preoperative one-stop radiation-free examination for patients at high risk for MTM surgery. [ABSTRACT FROM AUTHOR]

Oxidative stress is considered to be one of the culprits of ovarian dysfunction. Spermidine (SPD) is a natural aliphatic polyamine that is widely present in living organisms and has been shown to exert preventive effects on various ageing-related diseases. This study seeks to investigate the potential preventive and protective effects of SPD on ovarian oxidative damage. Ovarian oxidative stress model in C57BL/6 mice was established by 3-nitropropionic acid. Female mice were administrated 10 mg/kg or 15 mg/kg SPD. The estrous cycle, serum hormone levels and mating test were measured to evaluate ovarian function. Follicle counts and AMH levels to assess ovarian reserve. Masson's trichrome to assess ovarian fibrosis. TUNEL analysis to evaluate follicular granulosa cells (GCs) apoptosis. Oxidative stress and autophagy indicators (Nrf2, HO-1, GPX4, LC3B, P62) were measured in vivo and in vitro. RNA-sequencing was performed on SPD-treated GC to study the effects of SPD on Akt and FHC/ACSL4 signaling. SPD supplementation improved ovarian endocrine function and reproductive capacity in oxidative stress mice. SPD regularized the estrous cycle and alleviated oxidative stress. Furthermore, SPD increased the ovarian reserve, reducing GC apoptosis by activating the Nrf2/HO-1/GPX4 pathway. RNA-sequencing showed that SPD induced 230 genes changes in porcine GC, which were mainly involved in oocyte meiosis, arginine biosynthesis and glutathione metabolism pathways. SPD attenuated H 2 O 2 -induced ferroptosis by regulating Akt/FHC/ACSL4 signaling. SPD alleviates oxidative stress and ferroptosis by regulating the Nrf2/HO-1/GPX4 and Akt/FHC/ACSL4 pathway, which may be a novel potential strategy to protect ovarian oxidative damage. [Display omitted] [ABSTRACT FROM AUTHOR]