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Ferroelectricity and magnetism seldom coexist due to mutual exclusiveness. Recent attempts have been made to achieve the coexistence of ferroelectricity and magnetism in polar magnets. In this paper, we investigated the magnetic properties, dielectric relaxation, and magnetodielectric (MD) effect of polar Dy2Cu2O5 ceramic. At the antiferromagnetic ordering temperature, the dielectric constant (ɛ) curves exhibit a spontaneous change in slope, indicating strongly coupled charge and spin degrees of freedom. With increase in the magnetic field intensity, the simultaneous suppression of the dielectric anomaly and the antiferromagnetic transformation demonstrates the existence of the MD effect. It is important to note that ɛ varies nonmonotonically with the magnetic field. Below the magnetic ordering temperature, ɛ increases continuously before the metamagnetic transition and then decreases after that. The results are discussed in terms of the magnetic field-induced change of spin configuration and spin–phonon coupling. Moreover, two dielectric relaxation-related steps are observed, which are correlated with the electrons hopping within and among the zigzag chains of Cu2+, respectively. This work helps understand the dielectric behavior and the MD effect in materials with complicated spin structures. [ABSTRACT FROM AUTHOR]

Vegetation phenology is an important indicator of environmental change and strongly connected to forest ecosystem productivity change. This study aimed to analyse the pattern of phenological variations derived from digital imagery for the interpretation of ecosystem productivity. For 2014, 2015 and 2016, the seasonal phenological development of savanna was analysed by using towerbased imagery from a digital camera. The green excess index (GEI) was the best at representing the phenological transition dates (PTDs) and useful for investigating the gross primary production (GPP) in the savanna ecosystem. There was a significant correlation between the monthly pattern of the strength of green (Sgreen), green excess index (GEI) and vegetation contrast index (VCI) and GPP throughout the year. Additionally, the annual pattern of colour indices had significant relationship (p < 0.05) with GPP but this was not seasonal. The air temperature (air T) and soil temperature (soil T) were strongly significantly correlated (p < 0.001) with the start of growing season (SGS) and caused the advance in green-up and the timing of the start of the growing season in 2014 and 2016. The short growing season length (GSL) had an impact on the productivity. The colour indices from the digital camera images not only provided the phenological pattern of a forest canopy but also revealed the forest ecosystem productivity by showing the response to environmental factors. Our results indicate that daily continuous digital camera images might be useful for ecologists to use as a tool for future prediction of the long-term phenological modelling. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aims to evaluate the changes in left ventricular diastolic function after coronary artery bypass grafting through tissue Doppler imaging (TDI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration and the correlation between the two. PATIENTS AND METHODS: A total of 133 patients who underwent coronary artery bypass grafting between January 2016 and December 2018 were included in this study. Echocardiography and NT-proBNP concentration were reviewed pre-operation, 1 month post-operation, and 3-6 months post-operation. The transmitral peak flow velocity (E) of the mitral valve was measured at each of the three-time points using spectral Doppler imaging. The mitral annulus displacement (Ea peak and Aa peak) was then measured at each of the time points using TDI, and the E/Ea ratio was calculated. Subsequently, the correlation of the E value, Ea value, and E/Ea ratio with NT-proBNP concentration was statistically analyzed. RESULTS: The data obtained at the threetime points were compared with the respective concentrations of NT-proBNP. Multiple linear regression analysis revealed a correlation between NT-proBNP concentration and E value, Ea value, and E/Ea ratio. CONCLUSIONS: Left ventricular diastolic function gradually recovered at 1 month and 3-6 months after coronary artery bypass grafting. There was a correlation between TDI-related values and NT-proBNP concentration. [ABSTRACT FROM AUTHOR]

Ar + H2 plasma interacting with liquid lithium was carried out on a one-cathode linear plasma device (SCU-PSI). The lithium sample was covered with capillary porous structure (CPS). It is found that the electron temperature of applied plasma ranged from ~0-1 eV and electron density ranged from 0.1 × 1020 to 1 × 1020 m−3. The experimental results indicate that a reduction in the electron temperature and the lithium evaporation is found as the percentage of H2 increases When the ratio of argon and hydrogen keeps constant, the electron temperature and lithium evaporation increase with applied input power, respectively. The retention of hydrogen atoms in lithium surface results in reducing the lithium evaporation. The XRD analysis result shows that during plasma radiation no LiH is formed. [ABSTRACT FROM AUTHOR]

The optical band positions and spin-Hamiltonian parameters (g factors gi and hyperfine structure constants Ai, where i = x; y; z) of the rhombic VO2+ complex in CsCl crystal are calculated together from two theoretical methods. One is the complete diagonalization (of energy matrix) method and another is the perturbation theory method. The calculated results from the two methods coincide and are in reasonable agreement with the experimental values. So, both methods are effective in the explanations of optical and electron paramagnetic resonance (EPR) data for d¹ ions in crystals. The calculations also suggest that in d¹ rhombic octahedra the ground state is almost a pure ∣dxy∣ state. This point is different from that of conjugate d9 (e.g., Cu2+) ions in rhombic octahedra where the ground state should be an admixture of ground and first excited states. [ABSTRACT FROM AUTHOR]

β-sialon/Ti (C, N) composite powders were synthesized via a carbothermal reduction nitridation (CRN) method using low-grade bauxite and ilmenite as starting materials and coke as the reducing agent. Then the composites were sintered from the β-sialon/Ti(C, N) composite powders in nitrogen atmosphere with Y2O3 and Al2O3 as sintering aids. In this study, long columnar β-sialon decomposed completely to short columnar AIN-polytypoids and lamellar AlN when sintered at 1500 °C. With an increase in sintering temperature, the volume density of the composites synthesized from low-grade bauxite decreased. The bending strength was 23.3 MPa when sintered at 1600 °C, and the apparent porosity reached maximum value of 57.2 % when sintered at 1500 °C. When the sintering temperatures increased, the volume density of the composites sintered from low-grade bauxite and ilmenite increased. The bending strength reached 25.0 MPa when sintered at 1600 °C, and the apparent porosity reached the maximum value of 59.7 % when sintered at 1500 °C. [ABSTRACT FROM AUTHOR]

Two series of Al2O3−β-Sialon/Ti(C, N)/SiC−C refractories were prepared using tabular corundum, brown corundum, SiC, Al2O3 micropowders, β-Sialon/Ti(C, N) composite powders, silica fume, asphalt, metallic silicon and aluminium powders as the raw materials and aluminium dihydrogen phosphate as the bonding agent. The effects of aluminium dihydrogen phosphate on permanent linear change (PLC), bending strength, compression strength and oxidation resistance of unfired Al2O3−β-Sialon/Ti(C, N)/ SiC−C refractories were investigated. The oxidation resistance mechanisms of the Al2O3−SiC/β-Sialon/Ti(C, N)−C refractories were also discussed. The results illustrated that the Al2O3−SiC/β-Sialon/Ti(C, N)−C refractories had lower PLC, and higher bending strength and compression strength when cured at room temperature (20 °C) and 110 °C when using aluminium dihydrogen phosphate as the bonding agent. Al2O3−β-Sialon/ Ti(C, N)/SiC−C refractories also had great oxidation resistance in these recipes. [ABSTRACT FROM AUTHOR]

Ferroelectricity and magnetism seldom coexist due to mutual exclusiveness. Recent attempts have been made to achieve the coexistence of ferroelectricity and magnetism in polar magnets. In this paper, we investigated the magnetic properties, dielectric relaxation, and magnetodielectric (MD) effect of polar Dy2Cu2O5 ceramic. At the antiferromagnetic ordering temperature, the dielectric constant (ɛ) curves exhibit a spontaneous change in slope, indicating strongly coupled charge and spin degrees of freedom. With increase in the magnetic field intensity, the simultaneous suppression of the dielectric anomaly and the antiferromagnetic transformation demonstrates the existence of the MD effect. It is important to note that ɛ varies nonmonotonically with the magnetic field. Below the magnetic ordering temperature, ɛ increases continuously before the metamagnetic transition and then decreases after that. The results are discussed in terms of the magnetic field-induced change of spin configuration and spin–phonon coupling. Moreover, two dielectric relaxation-related steps are observed, which are correlated with the electrons hopping within and among the zigzag chains of Cu2+, respectively. This work helps understand the dielectric behavior and the MD effect in materials with complicated spin structures. [ABSTRACT FROM AUTHOR]

Objective: To explore the effect of macrophage-derived exosomes on the activation of hepatic stellate cells and its possible mechanism. Methods: Differential ultracentrifugation was used to extract macrophage exosomes. The exosomes were co-cultured with the mouse hepatic stellate cell line JS1, and a control group was established with phosphate buffered saline (PBS). Cell immunofluorescence was used to observe the expressional conditions of F-actin. Cell counting kit-8 (CCK8) was used to detect the survival rate of JS1 cells in the two groups. The activation indices of JS1 cells [collagen type Ⅰ (Col Ⅰ) and α-smooth muscle actin (α-SMA)] and its key signal pathway activation index expression level [transforming growth factor (TGF)-β1/Smads, platelet-derived growth factor (PDGF)] in the two groups were determined using Western blot and RT-PCR. Data comparison between two groups was performed using an independent sample t-test. Results: The membrane structure of exosomes was clearly observed by transmission electron microscopy. The expression of exosome marker proteins CD63 and CD81 was positive, suggesting that exosomes were successfully extracted. Exosomes were co-cultured with JS1 cells. Compared with the PBS control group, there was no statistically significant difference in the proliferation rate of JS1 cells in the exosomes group ( P ＞0.05). The expression of F-actin was significantly increased in the exosome group. The mRNA and protein expression levels of α-SMA and ColⅠwere significantly increased in exosome group JS1 cells (all P ＜0.05). The mRNA relative expression levels of α-SMA in PBS and exosome group were 0.25±0.07 and 1.43±0.19, respectively, while that of ColⅠ was 1.03±0.04 and 1.57±0.06, respectively. The mRNA and protein expressions of PDGF were significantly increased in exosome group JS1 cells ( P ＜0.05). The mRNA relative expression levels of PDGF in the PBS group and exosome group were 0.27±0.04 and 1.65±0.12, respectively. There were no statistically significant differences in the mRNA and protein expressions of TGF-β1, Smad2 and Smad3 between the two groups ( P ＞0.05). Conclusion: Macrophage-derived exosomes significantly promote the activation of hepatic stellate cells. JS1 cells may be the underlying mechanism for the up-regulation of PDGF expression.

Objective: To explore the clinical characteristics and risk factors of patients with Coronavirus Disease 2019 (COVID-19) when developing multiple organ dysfunction syndrome (MODS). Methods: Data from 458 inpatients of confirmed COVID-19 in Wuhan, Shanghai and Tongling from December 29, 2019 to March 24, 2020 were retrospectively collected. COVID-19 was confirmed by real-time RT-PCR of throat swab samples. Data of demographics, clinical presentation, laboratory tests, imaging findings, treatment and prognosis were obtained from medical record and compared between COVID-19 patients with and without MODS. Risk factors for the development of MODS were analyzed by univariate and multivariate logistic regression analysis. Results: Of the 458 COVID-19 patients (266 from Wuhan, 208 from Shanghai, and 24 from Tongling), 103 developed transient or persistent MODS in the course. More male patients were found in those with MODS (72.8% vs 54.6%, P= 0.001). And MODS patients were of older age (72.8% vs 54.6%, P= 0.001), more chronic comorbidities (68.0% vs 43.4%, P <0.001), and longer onset-to-admission interval (9.0 vs 7.0 d, P <0.001). In addition, patients with MODS had more expectoration (45.6% vs 29.9%, P= 0.003) and shortness of breath (52.4% vs 19.4%, P <0.001), dysfunction of various systems, decreased cellular immunity and elevated IL-6 (9.6 vs 7.6 g/L, P= 0.015) in laboratory tests, isolation of other pathogens (18.4% vs 5.6%, P <0.001), and infiltration of all five lobes (75.3% vs 57.6%, P= 0.003). During hospitalization, patients with MODS needed a higher proportion of comprehensive treatment and reached a mortality rate of 66.0%. Independents risk factors for development of MODS in COVID-19 patients were: onset-to-admission interval>7 days ( OR =2.17, 95% CI : 1.11-4.22, P= 0.023), shortness of breath ( OR =3.19, 95% CI : 1.60-6.37, P= 0.001), lymphocyte count<1×10 9 /L ( OR =2.67, 95% CI : 1.31-5.46, P= 0.007), blood urea nitrogen>7mol/L ( OR =6.27, 95% CI : 2.80-14.08, P <0.001), procalcitonin>0.1 ng/mL ( OR =2.48, 95% CI : 1.20-5.13, P= 0.014), and C-reactive protein>10 mg/L ( OR =3.92, 95% CI : 1.41-10.89, P= 0.009). Conclusions: COVID-19 patients with MODS were of higher severity and mortality. Early identification of high-risk groups with MODS according to risk factors may be helpful for early treatment.

The aim of this study was to explore the dynamic changes in characteristic serum metabolic markers and pathways during early sepsis in rats. By using cecal ligation and puncture (CLP), we made rat models of sepsis, which were randomly divided into 5 groups with 10 rats in each group: group A, group B, group C, group D, and group E. We collected 2 mL of arterial blood at 0, 6, 12, 24, and 48 hours from rats in group A-E respectively and isolated serum via centrifugation. Next, adopting metabolomics analysis methods, we screened for metabolites from the animal serum with statistically and biologically significant abundance changes, and used the KEGG database to analyze the respective metabolic pathways. In all, our findings reveal that D-glucosamine 6-phosphate, D-glucosamine phosphate, α-D-glucosamine 1-phosphate, D-glucosamine 1-phosphate, and 5-hydroxy isocyanate decline continuously from 12 hours, while L-phenylalanine, (S) -α-amino-β-phenylpropionic acid, 5-methoxy indole acetic acid salt, 5-methoxy indole acetic acid, goose deoxyglycolic acid salt, goose deoxyglycolic acid, and Chen's deoxygenated sugar alcohol started to decrease from 6 hours. Additionally, 3.2,3-Bis-O-(geranyl geranyl)-sn-glycerol- 1-phosphoric acid-L-serine levels rose continuously from 12 hours. We found 13 differentially regulated ions, primarily ones involved in pathways responsible for the metabolism of sugar, amino acids, and lipids, which are related to the disorder of energy metabolism. Our findings mark serum-derived D-glucosamine and its phosphorous derivatives as characteristic metabolic markers of sepsis in rats., (Copyright 2020 Biolife Sas. www.biolifesas.org.)

Objective: To explore the risk factors of long-term treatment outcomes and establish predicting model for laparoscopic left hepatectomy in hepatolithiasis. Methods: Clinical data of 108 patients with hepatolithiasis who underwent laparoscopic left sided hepatectomy and with complete follow-up data were retrospectively collected from June 2011 to June 2016 at the Second Affiliated Hospital of Nanchang University. Twenty-six males and 82 females were enrolled. The age was (52.4±11.7) years (range:20-80 years) , and the median follow-up time was 36 months (range: 24-83 months) . Patients were randomly divided into training group (79 cases) and validation group (29 cases) with a ratio of about 3∶1. Twenty-five preoperative and intraoperative clinical factors were selected for potential factors that might affect long-term outcomes, and quality of life was used as an surrogate evaluation index. Univariate analysis and multivariate logistic regression analysis were used to investigate the potential risk factors, and to construct and validate the predictive nomogram for surgical outcomes. Results: Among 108 patients, 10 patients (9.3%) had residual stones, 8 patients (7.4%) had recurrent stones, 12 patients (11.1%) had recurrent cholangitis and 3 patients (2.8%) died. Univariate analysis showed that history of hepatobiliary surgery, gender, activation of partial thromboplastin time, alkaline phosphatase, use of choledochoscopy, postoperative stone residual, serum creatinine, postoperative biliary drainage and operation time were risk factors that may affect long-term outcomes (all P< 0.15) . Multivariate analysis showed that the history of previous hepatobiliary surgery ( OR= 2.305, 95% CI : 0.383-4.227, P= 0.019) , postoperative biliary drainage ( OR= 2.043, 95% CI : 0.182-4.209, P= 0.048) , operation time ≥262.5 minutes ( OR= 1.971, 95% CI : 0.154-4.023, P= 0.045) were independent risk factor affecting long-term outcomes. Based on the above factors, the predictive nomogram model was constructed. Internal and external validations showed good discrimination (area under the curve of receiver operating curve>0.7) and calibration (Hosmer-Lemeshow test: P> 0.05) performance, which indicated that the prediction effect was favorable. Conclusions: History of previous hepatobiliary surgery, postoperative biliary drainage and operation time ≥262.5 minutes are independent risk factors for long-term outcome. The predictive nomogram model based on risk factors relates to surgical outcomes presented good clinical predictive effects, which might contribute to the prediction of the long-term outcomes of laparoscopic left sided hepatectomy for hepatolithiasis.

Background and Purpose: Traumatic brain injury is a major public health problem worldwide. Accurately evaluating the brain microstructural changes in traumatic brain injury is crucial for the treatment and prognosis assessment. This study aimed to assess the longitudinal brain microstructural changes in traumatic brain injury in the rat using diffusional kurtosis imaging., Materials and Methods: Diffusional kurtosis imaging was performed in a group of 5 rats at preinjury and 3, 14, and 28 days after traumatic brain injury. The diffusional kurtosis imaging parameters were measured in the bilateral cortex, hippocampus, and corpus callosum. Another 4 groups of 5 rats were used in brain immunohistochemistry analysis of neuron (neuron-specific nuclear protein [NeuN]), astroglia (glial fibrillary acidic protein [GFAP]), microglia (ionized calcium binding adaptor molecule 1 [Iba-1]), and myelin (myelin basic protein [MBP]) in the same area as the diffusional kurtosis imaging parameter measurements. Furthermore, 2 groups of 6 rats underwent a Morris water maze test at 28 days after traumatic brain injury. The diffusional kurtosis imaging parameters, immunohistochemistry results, and Morris water maze test results were compared longitudinally or between traumatic brain injury and control groups., Results: Compared with baseline, traumatic brain injury in the rat showed higher mean kurtosis and mean diffusivity values in the ipsilateral perilesional cortex and hippocampus and lower fractional anisotropy values in the corpus callosum ( P < .05). The traumatic brain injury group showed higher staining of GFAP and Iba-1 and lower immunohistochemistry staining of NeuN and MBP in all ipsilateral ROIs ( P < .05). There was no significant difference in the contralateral ROIs in diffusional kurtosis imaging parameters or immunohistochemistry results. The Morris water maze test revealed lower platform crossing times in the probe test ( P < .05)., Conclusions: Our study indicated that there were longitudinal changes in diffusional kurtosis imaging parameters, accompanied by multiple pathologic changes at different time points following traumatic brain injury, and that mean kurtosis is more sensitive to detect microstructural changes, especially in gray matter, than mean diffusivity and fractional anisotropy., (© 2018 by American Journal of Neuroradiology.)

A novel and simple fiber-optic sensor based on a superstructure fiber grating for simultaneous measurement of temperature, axial strain, and transverse load is proposed and demonstrated. By measurement of the shift and split of broadband and narrow-band loss peaks, one can determine the temperature, axial strain, and transverse load simultaneously over the ranges 0-140 degrees , 0-1200muepsilon, and 0-0.3 kg/mm, respectively.

Rapid epithelial repair (restitution) after injury is required to maintain barrier function of the gastrointestinal mucosa and skin and is thought to be a highly ATP-dependent process that would be inhibited under hypoxic conditions. However, little is known about the metabolic pathways required for restitution. Thus, this study was undertaken to evaluate, in vitro, the role of oxidative respiration and glycolysis in restitution after injury. To this end, restitution of the bullfrog gastric mucosa was evaluated under the following conditions: 1) blockade of mitochondrial respiration; 2) blockade of glycolysis; or 3) absence of glucose. The extent of mucosal repair after injury was evaluated by electrophysiology and morphology. Cell migration, repolarization, and the formation of tight junctions after injury occurred during blockade of mitochondrial respiration, whereas the recovery of mucosal barrier function did not. In contrast, glycolytic inhibition completely blocked all aspects of restitution by inhibiting the migration of surface epithelial cells. Restitution occurred in tissues incubated with glucose-free solutions, suggesting that cells contain sufficient glucose (glycogen) to drive glycolysis for many hours. Our results demonstrate that the glycolytic pathway is essential for restitution after injury in the bullfrog gastric mucosa and that all but complete repair of barrier function occurs in the absence of mitochondrial respiration.