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To optimize the reactant synthesis and improve the pressure property of Al/Bi2O3, the influencing factors in the dynamic pressure discharge of nanothermite reactions are investigated, including the oxide type, Bi2O3 particle size, and fuel-to-oxidant mole ratio. All samples are prepared by the ultrasonic mixing method. The synthesized Al/Bi2O3 composites are characterized by X-ray diffraction analysis and scanning electron microscopy. By using a closed bomb, the pressure discharge characteristics, including the peak pressure, ignition delay time, and pressurization rate, are obtained. Among the as-prepared nanothermites Al/CuO, Al/Fe2O3, and Al/Bi2O3, the latter shows the best pressure discharge performance. For the Al (100 nm)/Bi2O3 (47 nm) composite with an optimal stoichiometric ratio, the maximum peak pressure, the pressurization rate, and the shortest ignition delay time are 4559 kPa, 11.398 GPa/s, and 27.20 ms respectively. The results indicate that the nano-Bi2O3 particle size also produces a significant effect on the pressure output. [ABSTRACT FROM AUTHOR]

Structure and transport properties of Eu-doped YBa2-xEuxCu3O7-δ (YBECO) have been studied. Eu is confirmed preferring to replace Ba at Ba sites. The averaged valence state of Eu, which is examined by x-ray photoemission spectroscopy, increases with increasing x. Eu doping in YBECO has a little influence on superconductivity in our studies, and the superconducting transition temperature Tc is almost unchanged. [ABSTRACT FROM AUTHOR]

We have observed that the extraordinary Hall resistance of Pt/Co/Pt sandwich with perpendicular magnetic anisotropy changes from positive to negative drastically as the current density increases in an applied field, indicating the magnetization switching induced by the current. There exists a critical current density that changes for the different applied field with the order of current density of 104 A/cm2, which is much lower than that reported in literatures on the current-induced magnetization switching. The results of the extraordinary Hall effect of the sample in different in-plane current density show that the magnetization-switching field decreases with the increment of current density when the current density is larger than 104 A/cm2. [ABSTRACT FROM AUTHOR]

Presents a study which examined the magnetooptical Kerr effect in Fe-SiO[sub2] granular films. Overview of previous studies on the magnetic properties of granular materials; Discussion on the microstructure of Fe-SiO[sub2] granular films; Factors which give way to the Kerr effect.

Presents a study which examined the magnetic properties of FeSi-SiO[sub2] granular films. Characteristics of granular solids; Experimental setup; Measurement of the coercivities of the films using a vibration sample magnetometer at room temperature; Analysis of the ferromagnetic resonance spectra.

Objective: The aim of this study was to facilitate the systematic discovery of diagnostic bio-markers of diabetic nephropathy (DN). Methods: 3 publicly available independent cohorts were got from Gene Expression Omnibus database. Gene expression array were used to screen for genome-wide relative significance (GWRS) and genome-wide global significance (GWGS). The most significant up- and down-regulated top 100 gene signatures were identified using a fold change based model. Then the protein-protein interaction (PPI) network was constructed, while the hub genes in this PPI network were identified by centrality analysis. Modules detection was performed to explore the functions of the modules. Meanwhile, gene enrichment analysis was performed to illuminate the biological pathways and processes associated with DN. Results: The most significant up- and down-regulated top 100 gene signatures were identified and a PPI network was established. Several hub genes (VEGFA, IL8, MYC, CD14, ALB) were discovered. Several functional modules were revealed. Biological pathways including cytokine-cytokine receptor interaction and p53 signaling pathway, and processes including inflammatory response, response to wounding and enzyme linked receptor protein signaling pathway were identified. Conclusion: Our study displayed underlying biomarkers including biological pathways and several hub genes of DN. [ABSTRACT FROM AUTHOR]

The structure and transport properties for La2/3Ca1/3MnO3 (LCMO)/YBa1.8Eu0.2Cu3O7 (YBECO) multilayers are studied. The lattice constants for each sub-layer decrease with decreasing the temperature. The morphology of the films depends on the thickness of each sub-layer. Grains growing on the surface of each sample are believed to release the lattice strain. We believe that the lattice strain may affect the transport properties of LCMO and YBECO in the periodic films. The grains appearing on the surface of the film may enlarge the width of the superconducting transition of YBECO, and the metal-to-insulator transition of LCMO. [ABSTRACT FROM AUTHOR]

The effects of Sc in high Tc superconductors are seldom discussed due to the difficulty of Sc embedding into the unit cell. Single phase of Y1-xScxBa2Cu3O7-δ (YSBCO) is obtained with x<0.15. The critical current (Jc) varies with the content of Sc in an oscillating way, which has showed two maximum values at x=0.03 and x=0.10, individually. We here discussed the effect of Sc doping on Jc. [ABSTRACT FROM AUTHOR]

With varying the content of Ca, single phase of La0.7Ca0.3-xMnO3 (LCMO) with Pnma symmetry have been studied. There is no phase transition detected with varing the content of Ca. The divergence of Mn-O1(ax) and Mn-O2(eq) values indicates the occurrence of lattice distortions. No marked variations of Mn-O1-Mn and Mn-02-Mn bond angles are observed. The insulator-metal transition temperature TMI of samples shifts to lower values with increasing vacancy content. At low temperature region, a large MR (30∼45%) is observed. We attribute it to the grain boundary tunnel effect. [ABSTRACT FROM AUTHOR]

The lattice strain distributions of epitaxial SrTiO3 films deposited on LaAlO3 were investigated by in situ x-ray diffraction at the temperature range of 25–300 K, grazing incident x-ray diffraction, and high resolution x-ray diffraction. The nearly linear temperature dependence of the out-of-plane lattice constant of SrTiO3 was observed in the measured temperature range. The depth distribution of the lattice strain at room temperature for SrTiO3 films includes the surface layer, strained layer, and interface layer. [ABSTRACT FROM AUTHOR]

To optimize the reactant synthesis and improve the pressure property of Al/Bi2O3, the influencing factors in the dynamic pressure discharge of nanothermite reactions are investigated, including the oxide type, Bi2O3 particle size, and fuel-to-oxidant mole ratio. All samples are prepared by the ultrasonic mixing method. The synthesized Al/Bi2O3 composites are characterized by X-ray diffraction analysis and scanning electron microscopy. By using a closed bomb, the pressure discharge characteristics, including the peak pressure, ignition delay time, and pressurization rate, are obtained. Among the as-prepared nanothermites Al/CuO, Al/Fe2O3, and Al/Bi2O3, the latter shows the best pressure discharge performance. For the Al (100 nm)/Bi2O3 (47 nm) composite with an optimal stoichiometric ratio, the maximum peak pressure, the pressurization rate, and the shortest ignition delay time are 4559 kPa, 11.398 GPa/s, and 27.20 ms respectively. The results indicate that the nano-Bi2O3 particle size also produces a significant effect on the pressure output. [ABSTRACT FROM AUTHOR]

We report a method to switch both the circulation and polarity of magnetic vortices in a controlled manner within a nanosecond utilizing micromagnetic simulations. The controllable switching is achieved with the combination of two different types of magnetic field pulses on submicron permalloy disks with heptagonal shape. When a magnetic field pulse of ~100 mT is applied along one of the edge directions of the heptagon, the circulation of the vortex can be manipulated according to the pulse direction. When a pair of pulses with a few tens of mT in magnitude and relative delay of about 100 ps is applied in orthogonal directions, the polarity can be further controlled without influencing the circulation. The different magnitude of switching fields allows for the combination of both types of pulses in the control of both the circulation and polarity of magnetic vortices. The switching mechanism and the controlling parameters for disks with diameters of 500 and 700 nm are discussed. [ABSTRACT FROM AUTHOR]

Denosumab, a human monoclonal antibody, is used for the prevention of malignant tumor-related bone events and the treatment of osteoporosis with high fracture risk. Since its approval in China in 2019, denosumab-related osteonecrosis of the jaw (DRONJ) has attracted increasing attention. DRONJ, similar to bisphosphonate-related osteonecrosis of the jaw, often occurs after tooth extraction and manifests as exposed bone necrosis, purulent discharge, facial swelling and pain, severely impacting patients' quality of life. However, the perioperative management strategies for DRONJ differ from those for bisphosphonate-related osteonecrosis of the jaw. This article summarizes the perioperative management strategies for high-risk DRONJ patients from aspects such as oral hygiene care, antibiotic use, drug discontinuation during the perioperative period, and surgical strategy selection, aiming to provide guidance for oral surgeons in managing tooth extraction in denosumab-treated patients.

Objective: This study aimed to detect serum level of glucose regulated protein 78(GRP78) in patients with obstructive sleep apnea(OSA) and explore the relationship between endoplasmic reticulum stress and the pathophysiology of OSA., Methods: A total of 91 patients with OSA were enrolled in this study, including 30 mild, 28 moderate and 33 severe. The other 27 obese subjects were of age, gender and BMI matched group. Eleven moderate or severe OSA patients were administrated with continuous positive airway pressure (CPAP) treatment for 24 hours. Polysomnography, apnea hypopnea index (AHI), lowest arterial oxygen saturation(SaO2) and percentage of time spent at SaO2 below 90% (SIT90) were measured before and after sleep. Serum GRP78 was measured by ELISA., Results: The expression of GRP78 in mild(3.42±0.97)μg/L, moderate(2.67±1.14)μg/L and severe(2.62±1.11)μg/L OSA groups was significantly higher than in control group(1.75±0.41)μg/L (P<0.05). The GRP78 level in mild OSA group was significantly higher than either moderate or severe OSA group (P<0.05). After 24 h treatment of CPAP, serum GRP78 level decreased significantly [(1.77±0.39)μg/L vs(2.84±0.39)μg/L; P<0.05]., Conclusions: Endoplasmic reticulum stress involves in the pathophysiology of patients with OSA. Higher GRP78 level in mild OSA patients suggests that endoplasmic reticulum related protein GRP 78 might rise then fall during exacerbation of OSA.

We investigated the methylation state of the epidermal growth factor receptor (EGFR) gene promoter in non-small cell lung cancer (NSCLC) and analyzed its effect on tumor biology. We enrolled 120 patients with NSCLC who had been confirmed by pathologic diagnosis and had been operated on. The methylation states of the EGFR gene promoter were detected and analyzed and a prognosis was given. NSCLC cell lines and nude mice were used to study the treatment reactivity of gefitinib (an EGFR inhibitor) with or without 5-aza-2'-deoxycytidine (5-aza-CdR) intervention. EGFR expression was high when the methylation degree was lower in patients with adenocarcinoma and poor pathological differentiation of tumor than in patients with squamous cell carcinoma and good pathological differentiation. NSCLC cells with low expression of EGFR and high methylation in the promoter region were insensitive to EGFR-targeted therapy. However, apoptosis and proliferation inhibition of cancer cells were even more pronounced when 5-aza-CdR was used to inhibit methylation. An in vivo study confirmed that methylation adjuvant therapy can improve the sensitivity of cancer to EGFR-targeted therapy. Application of a demethylating agent could be an important supplement for improving EGFR inhibition in the treatment of NSCLC, especially in those who are insensitive to the use of an EGFR inhibitor alone.

Myocardial ischemic preconditioning upregulated protein 1 (Mipu1) is a newly discovered upregulated gene produced in rats during the myocardial ischemic preconditioning process. Mipu1 cDNA contains a 1824-base pair open reading frame and encodes a 608 amino acid protein with an N-terminal Krüppel-associated box (KRAB) domain and classical zinc finger C2H2 motifs in the C-terminus. Mipu1 protein is located in the cell nucleus. Recent studies found that Mipu1 has a protective effect on the ischemia-reperfusion injury of heart, brain, and other organs. As a nuclear factor, Mipu1 may perform its protective function through directly transcribing and repressing the expression of proapoptotic genes to repress cell apoptosis. In addition, Mipu1 also plays an important role in regulating the gene expression of downstream inflammatory mediators by inhibiting the activation of activator protein-1 and serum response element.

The study was undertaken to investigate the effect of basic fibroblast growth factor (bFGF) on aortic production of nitric oxide (NO) and endothelin of aorta in spontaneously hypertensive rats (SHR) and WKY rats. Rat aortas were cut into vessel slices and incubated with 10 or 100 ng/ml bFGF for 6 hours. Nitric oxide synthase (NOS) activity in aortic slices and contents of NO(-)(2) and endothelin in the medium were determined. The results showed that NOS activity in aortic slices of SHR was 17.6% lower than that of WKY (P<0.01). NO(-)(2) and endothelin contents in the medium of SHR aortic slices were 59.7% lower and 37.4% higher than those of WKY aortic slices. Upon the exposure of low and high doses of bFGF, NOS activity in the aorta of SHR was increased by 29.7% and 59.6% (both P<0.01),respectively, while the NO(-)(2) contents in the medium were increased respectively by 28.2% (P<0.05) and 70.5% (P<0.01). Aortic endothelin production was increased by 24.1% and 44.5% (both P<0.01) respectively while the NOS activity in the aorta of WKY was increased by 24.4% and 53.7% (both P<0.01). NO(-)(2) contents in the medium were augmented by 18.8% (P<0.05)and 25.9% (P<0.01), respectively. Aortic endothelin production was increased by 84.1% and 93.1% (both P<0.01). It is concluded that bFGF may modulate the production of NO and endothelin in both SHR and WKY rats.

The effects of plasmid pcDNA3 on Ca(2+) transport of sarcoplasmic reticulum (SR) in ischemic skeletal muscle was investigated. The results show that Ca(2+) transport (including Ca(2+) uptake and Ca(2+) release) rate of SR in ischemic skeletal muscle was markedly increased compared with that in non-ischemic muscle (P<0.01 or P<0.05). After plasmid pcDNA3 bound to the DNA binding proteins of SR, Ca(2+) transport of SR was further increased. The results suggest that the effect of plasmid DNA on the ability of Ca(2+) transport in SR of ischemic skeletal muscle is the same as is observed in normal skeletal muscle. The pathophysiological significance of the present finding deserves further exploration.

Aim: To study the effect of batroxobin(Bat) on dog heart ischemia/reperfusion (I/R) injury., Methods: Dog heart I/R injury was induced by occluding the left anterior descending coronary artery for 30 min and restoring blood perfusion for 90 min. Bat was intravenously injected before heart ischemia and 15 min before reperfusion. Plasma creatine kinase (CK), lactate dehydrogenase (LDH), and myocardial malondiaedehyde (MDA) concentrations were measured. The pathologic changes of I/R myocardium were observed., Results: Bat reduced the mortality rate of I/R dog (I/R group 65.0% vs Bat-I group 30.0% and Bat-II group 28.6%, P < 0.05). Myocytes of I/R heart showed intracellular edema, damaged mitochondria, and concentrated nucleus. Bat decreased these changes. In Bat-I and Bat-II group, plasma CK and LDH level were reduced, the +dp/dtmax and -dp/dtmax at 30 min after ischemia and 90 min after reperfusion were elevated, and left ventricular end dilation pressure (LVEDP) was lowered. The myocardial MDA contents were decreased by 42.3% and 38.1% (P < 0.01) in Bat-I and Bat-II group, respectively., Conclusion: Bat may exert an apparent role against dog heart ischemia/reperfusion injury and improve myocardial function.

The present study was undertaken to observe the role of calcineurin (CaN)-dependent signaling pathway in the angiotensin II (Ang II)-induced cardiac myocyte hypertrophy. In cultured myocardial cells of neonatal rats, Ang II was used to stimulate hypertrophy and CaN-pathway blocked by CsA(an inhibitor of CaN). 3H-leucine incorporation, and activities of CaN, mitogen-activated protein kinase (MAPK) and protein kinase C (PKC) were investigated. The results showed that 3H-leucine incorporation of Ang II-stimulated myocardial cells was 46% higher than control (P < 0.01), which could be inhibited by CsA (0.5-5 micrograms/ml) and PD098059(an inhibitor of MAPK). CaN and PKC activities of Ang II-stimulated myocardial cells were 39% and 280% higher than control (P < 0.001) respectively, while no significant increase in MAPK activities was observed. CsA could reverse the increase of CaN activity, but had no effect on PKC. It is concluded that the CaN-dependent signaling pathway may play an important role in the development of the Ang II-induced cardiac myocyte hypertrophy.

Objective: To explore the possible relationship between Syndrome-Type in TCM and the superoxide dismutase (SOD) as well as malonyldialdehyde (MDA)., Methods: Serum SOD and MDA were measured in 61 patients with non-insulin dependent diabetes mellitus (NIDDM) and 20 normal subjects., Results: SOD activity of the NIDDM patients blood were clearly lower than those of normal subjects, but MDA were markedly elevated. From the Syndrome-Type of Yin Deficiency with Hyperactivity of Heat, to both Qi and Yin Deficiency, to both Yin and Yang Deficiency, or from without hemostasis to with the appearance of hemostasis in order. The SOD activity decreased and meanwhile MDA increased gradually., Conclusions: SOD activity and MDA levels in patients with NIDDM were associated with Syndrome-Type in TCM, it might be responsible for the diagnosis of Syndrome-Type in TCM.

Objective: To assess the effect of Salvia Miltiorrhiza Composita (SMCo) in treating non-insulin-dependent diabetes mellitus (NIDDM)., Methods: The superoxide dismutase (SOD) and malonyldialdehyde (MDA) levels of 20 patients with NIDDM were observed before and after treatment with Salvia Miltiorrhiza Composita and 20 patients without using SMCo were studied as controls., Results: The SOD levels were significantly lower than that of normal (P < 0.05), and MDA significantly increased (P < 0.01). After treatment with SMCo, the SOD levels were significantly increased (P < 0.01), there was no difference between the treatment group and the normal group. In the control group, the SOD levels had increase tendency and MDA had decrease tendency, but there was significant difference compared with the normal (P < 0.05, P < 0.01 respectively). The total effective rate of anti-lipid peroxidation injury in the group combined with intravenous SMCo was markedly higher than in the group without SMCo therapy (90% vs 60%, P < 0.01)., Conclusion: SMCo could resist lipid peroxidation injury.

Sixty kinds of commonly used Chinese medicines have been examined for their ability to depress the release of Lambda phage from lysogenic strain in the inductest. 11 Chinese medicines showed an inhibitory effects. Among them, Codonopsis radix, Polygonatum radix and fractus Lycium were strong depressors. They also showed an inhibitory effect on SOS response in SOS chromotest with a dose-effect response. These medicines were also found to decrease the frequency of gene conversion in S. cerevisiae in the presence of hydroxyurea. The effective compound (s) of Polygonatum radix partially purified from the extract with Sephadex G-25 chromatography was a reductive carbohydrate with molecular weight less than 3,000. The compound was shown to exert an inhibitory effect on SOS response occurred at 42 degrees C in E. coli GW1060 (recA441), but has no effect on SOS network gene expression in E. coli GW 1107 (lexA51), suggesting that Polygonatum radix may contain an inhibitor of RecA protease.

A 23-mer oligonucleotide based on the core sequence was chemically synthesized and used to screen the human genomic library. Fifteen positive recombinants containing the minisatellite sequences were identified, and one of them, C35.9, was used to perform Southern hybridization with the DNAs from unrelated Chinese individuals. Each sample has 3-11 hybridizing bands, and some of which are polymorphic. The band patterns detected under controlled condition are individual-specific in a limited population. This indicates that the minisatellites obtained by screening the library can be used to detect the polymorphisms of the minisatellites.