BaTiO3(BT) has attracted extensive attention among advanced lead-free ferroelectric materials due to its unique dielectric and ferroelectric properties. However, the enormous remanent polarization ...and coercive field severely impede the improvement of its energy storage capabilities. Here, the BaTiO3Bi(Zn0.5Hf0.5)O3 (BT-BZH) ceramics with high breakdown field strength and remarkable relaxation characteristics can be obtained by introducing the composite component BZH in BT to regulate the phase structure and grain size of the ceramics. The findings demonstrate that the improvement of energy storage performance is related to the increase of relaxation behavior. A large energy storage density (Wrec∼3.62 J/cm3) along with superior energy storage efficiency (η∼88.5%) is achieved in 0.88BT-0.12BZH relaxor ceramics only at 240 kV/cm. In addition, the sample suggests superior thermal stability and frequency stability within 25–115 °C and 1–500 Hz, respectively. Furthermore, the outstanding charge-discharge properties with an ultrafast discharge time (100 ns), large discharged energy density (1.2 J/cm3), impressive current density (519.4 A/cm2) and power density (31.1 MW/cm3) under the electric field of 120 kV/cm are achieved in studied ceramics. The excellent energy storage performance of BT-BZH ceramics provides a promising platform for the application of lead-free energy-storage materials.
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•BZH doping enhances the relaxation behavior, improving the energy storage property.•The excellent energy performance was realized only at a low applied field.•The as-prepared ceramic possesses large Wrec (3.62 J/cm3) and ultrahigh η (88.5%).•The outstanding thermal and frequency stability were obtained.•The discharge energy density and time were 1.2 J/cm3 and 100 ns, respectively.
Objective
Fracture is a common consequence of osteoporosis and is associated with high morbidity and mortality. Recently, increasing evidence has suggested that polymorphisms in tumor necrosis ...factor‐α (TNF‐α) gene were associated with osteoporosis risk and bone mineral density (BMD), but results remain conflicting. We herein performed a meta‐analysis based on evidence currently available from the literature to make a more precise estimation of these relationships.
Methods
The PubMed, EMBASE, Cochrane Library, CNKI (China National Knowledge Infrastructure) and Wan Fang databases were searched for eligible studies. Articles meeting the inclusion criteria were comprehensively reviewed and all available data were accumulated. The pooled odds ratios (ORs) or mean differences (MDs) and corresponding 95% confidence intervals (CIs) were applied to assess the strength of the relationships.
Results
A total of 15 studies involving 5273 subjects were included in our meta‐analysis. The GG genotype of TNF‐α G308A was associated with an increased risk of osteoporosis under a mutant model (GG vs GA+AA: OR = 0.63, 95% CI: 0.51‐0.77, P < 0.0001, I2 = 31%). Additionally, we also observed a significant association between G308A polymorphism and BMD of lumbar spine (AA vs GG: P = 0.01, I2 = 53%). However, TNF‐α T1031C, C857T and C863A polymorphisms had no obvious impacts on osteoporosis risk.
Conclusions
The present meta‐analysis demonstrated that TNF‐α G308A polymorphism may act as a potential candidate biomarker for screening, diagnosis, and treatment of osteoporosis, which will help improve individualized therapy of osteoporosis patients in clinics.
Orientation related phase transitions of 0.76Pb(Mg1/3Nb2/3)O3-0.24PbTiO3 single crystals are studied. Values of the relaxation parameters (γ = 1.87–1.97) estimated from linear fits of the modified ...Curie-Weiss law indicate the relaxor nature. For (110) oriented single crystal, typical oxygen vacancies related high temperature dielectric relaxation behaviors are observed and analyzed. Orientations dependent electrocaloric effects of 0.76Pb(Mg1/3Nb2/3)O3-0.24PbTiO3 single crystals are first studied and reported, large reversible adiabatic temperature change (0.80K) and isothermal entropy change (0.66JK−1kg−1) are observed. Giant refrigeration efficiency (43.52) and high electrocaloric coefficient (0.041KcmkV−1) exceed the electrocaloric effect values in most bulk ferroelectrics in previous reports.
To determine the relationship between renal lipid content and intrarenal oxygenation in diabetic nephropathy by using noninvasive chemical shift-selective (CSS) imaging and blood oxygen ...level-dependent (BOLD) magnetic resonance (MR) imaging.
The study was approved by the institutional Committee on Animal Research. Lipid and water phantoms for CSS imaging were made, and BOLD MR imaging phantoms from arterial and venous blood samples were collected from rats. CSS imaging and BOLD imaging were performed to measure lipid contents and T2* in phantoms and kidneys of diabetic gene (db) db/db mice and wild-type mice after exposure to nitrogen (four per group) and injection of furosemide (four per group). Results of MR imaging-measured lipid contents and oxygen tension were compared with known values in phantoms and reference standard from mice with histologic data. Statistical analysis was performed with independent sample and paired sample t tests and Pearson correlation test.
Renal lipid content in db/db mice was significantly higher compared with that in control mice (9.40% ± 1.89 and 3.11% ± 0.57, respectively; P < .001). In addition, the lipid content in the cortex of db/db mice was significantly higher than that in medulla (12.73% ± 0.94 and 3.16% ± 0.50, respectively; P < .001). Correlation was significant between T2* measured with BOLD and oxygen tension in blood phantoms (r = 0.958; P < .001). Lower baseline T2* in diabetic kidney suggested lower oxygenation that reserved excess oxygen supply. Lower oxygenation in diabetic kidney cortex was observed after nitrogen exposure and furosemide injection.
Noninvasive CSS imaging and MR imaging of db/db diabetic mice revealed the relationship between the renal lipid content and intrarenal oxygenation in diabetic kidney. Lipid accumulation in diabetic kidney compromises the oxygenation of the renal tissue and made it more susceptible to renal hypoxia. Online supplemental material is available for this article.
Two novel actinobacteria, designated as SYSU M7M538T and SYSU M7M531, were isolated from oral of Eumetopias jubatus in Zhuhai Chimelong Ocean Kingdom, China. The cells of these microorganisms stained ...Gram-positive and were rod shaped. These strains were facultative anaerobic, and catalase-positive. Optimal growth occurred at 37 °C and pH 7.0 over 7 days of cultivation. Both strains possessed diphosphatidylglycerol, phosphatidylglycerol and phosphocholine as the major polar lipids. The main menaquinone was MK-9(H4). The major fatty acids were C16:0, C17:1w8c, C17:0, C18:1w9c and C18:0. Analyses of genome sequences revealed that the genome size of SYSU M7M538T was 2.1 Mbp with G + C content of 52.5 %, while the genome size of SYSU M7M531 was 2.3 Mbp with G + C content of 52.7 %. The ANI and 16S rRNA gene analysis results showed that the pairwise similarities between the two strains and other recognized Nitriliruptoria species were less than 64.9 % and 89.0 %, respectively. Phylogenetic analysis of the 16S rRNA gene sequences indicated that strains SYSU M7M538T and SYSU M7M531 formed a well-separated phylogenetic branch distinct from other orders of Nitriliruptoria. Based on the data presented here, these two strains are considered to represent a novel species of a novel genus, for which the name Stomatohabitans albus gen. nov., sp. nov., with the type strain SYSU M7M538T (=KCTC 59113T = GDMCC 1.4286T), are proposed. We also propose that these organisms represent a novel family named Stomatohabitantaceae fam. nov. of a novel order Stomatohabitantales ord. nov.
We evaluated dual-echo Dixon in-phase and out-of-phase (IP-OP), chemical shift imaging (CSI), and 1H MRS (hydrogen MR spectroscopy) in estimating fat content (FC) in phantoms and in livers of mice. ...Phantoms were made according to the volume percentage of fat ranging from 0% to 100%. The three MR methods were performed to measure FC in phantoms and in livers of obese leptin-deficient (ob/ob), human BSCL2/seipin gene knockout (SKO), and wild-type (WT) mice. The results were compared with known FC in phantoms and to a reference standard from mice by histological semiautomatic vacuole segmentation (HIS-S) procedure and liver lipid (LL) chemical analysis. In phantoms, CSI underestimated FC from 50% to 100%, to a lesser extent than IP-OP. In vivo, liver FC in ob/ob and SKO mice measured by the three MR methods were all significantly higher than that in WT mice. Liver FC measured by IP-OP were significantly lower than that measured by CSI and MRS, with no significant difference between CSI and MRS. CSI and MRS showed a linear correlation with LL analysis and with each other. IP-OP underestimated FC, whereas CSI and MRS were more accurate for quantifying FC in both phantoms and liver. CSI and MRS have the potential to replace HIS-S and LL analysis in longitudinal studies.
The hospital environment has been implicated in the enrichment and exchange of pathogens and antibiotic resistance, but its potential in shaping the symbiotic microbial community of hospital staff is ...unclear. This study was designed to evaluate the alteration of the gut microbiome in medical workers compared to non-medical controls.
A prospective cross-sectional cohort study was conducted in the intensive care unit (ICU) and other departments of a centre in north-eastern China. Faecal samples of 175 healthy medical workers—short-term (1–3 months) workers (n = 80) and long-term (>1 year) workers (n = 95)—and 80 healthy non-medical controls were analysed using 16S rRNA amplicon sequencing. The hospital environmental samples (n = 9) were also analysed.
The gut microbiomes of medical workers exhibited marked deviations in diversity and alteration in microbial composition and function. Short-term workers showed significantly higher abundances of taxa such as Lactobacillus, Butyrivibrio, Clostridiaceae, Clostridium, Ruminococcus, Dialister, Bifidobacterium, Odoribacter, and Desulfovibrio and lower abundances of Bacteroides and Blautia than the controls. Long-term workers showed higher abundances of taxa such as Dialister, Veillonella, Clostridiaceae, Clostridium, Bilophila, Desulfovibrio, Pseudomonas, and Akkermansia and lower abundances of Bacteroides and Coprococcus than the controls. The medical workers' department (ICU versus non-ICU) and position (resident doctor versus nursing staff) also impacted their gut microbiome. Compared with the non-ICU workers, workers in the ICU showed a significant increase in the abundances of Dialister, Enterobacteriaceae, Phascolarctobacterium, Pseudomonas, Veillonella, and Streptococcus and a marked depletion of Faecalibacterium, Blautia, and Coprococcus. In contrast with the nursing staff, the resident doctors showed a significant increase in Erysipelotrichaceae and Clostridium and a decrease in Bacteroides, Blautia, and Ruminococcus in the gut microbiome. Moreover, we found that the microbiota of hospital environments potentially correlated with the workers' gut microbiota.
Our findings demonstrated structural changes in the gut microbial community of medical workers.
•Qualitative and quantitative analysis of Lycoridis Radiatae Bulbus were performed.•Effective combinatorial markers of Lycoridis Radiatae Bulbus were characterized.•Galanthamine and ungerimine were ...proved synergy in AChE inhibitory in vitro.•An approach to identifying suitable markers for quality control of HMs was proposed.
Quality standardization of herbal medicines (HMs) is an important task with great challenges. Selection of abundant compounds as markers is currently a major approach for the quality control of HMs; however, such marker compounds are irrelevant to the bioactivities in many cases. Taking Lycoridis Radiatae Bulbus (LRB) as an example, we proposed a universal strategy to identify the effective combinatorial markers (ECMs) that are representative of the bioactivities of HMs, and took them as chemical markers for quality standardization. Fingerprinting and quantification were employed to find out the common components in various batches of medicines. The contribution of each common compound to the overall bioactivity was determined through fingerprint–bioactivity modeling, which based on the absolute quantification of each compound and the acetylcholinesterase (AChE) inhibitory activity of LRB. Two most effective compounds, ungerimine and galanthamine, were therefore proposed as ECMs. Interestingly, these two compounds could synergistically inhibit AChE. This approach demonstrated its strong advantage of the bioactivity relevant quality assessment when compared with conventional methods. And the success of applying this ECMs-based method to the quality assessment of unknown LRB samples proved that our approach was reliable and reproducible. In conclusion, this approach is not only useful for the bioactivity relevant quality control of HMs but also helpful for the discovery of ECMs as new drug candidates.
More and more researchers start to pay attention to the electrocaloric temperature change (ΔT) in polar materials, which is caused by an applied electric field. In this paper, Ba-doped PbHfO3 (PBH) ...films were prepared by sol-gel method. Their components, microstructures, dielectric polarization and electrocaloric effects (ECEs) were investigated. With the addition of Ba2+, PBH films went from antiferroelectric (AFE) to ferroelectric (FE). At the same time, their dielectric peaks shifted toward lower temperature. The maximum ΔT obtained in Pb0.8Ba0.2HfO3 FE film is 41.1 K, which is an order of magnitude larger than PbHfO3 film (ΔT ∼ −4 K at 50 °C) and Pb0.9Ba0.1HfO3 film (ΔT < 4 K at 120 °C). In order to explain this phenomenon, the Landau-Devonshire theory was adopted. Our analysis shows that the rapid variation of energy barrier height near the phase transition temperature is beneficial to obtain large polarization change and high △T, which is needed in solid-state cooling devices.
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•Ba2+ can regulate the phase transition of Pb1-xBaxHfO3 films from antiferroelectric to ferroelectric.•The electrocaloric effect is enhanced from −4 K in PbHfO3 film to 41.1 K in Pb0.8Ba0.2HfO3 film.•The large △T over wide temperature range in Pb0.8Ba0.2HfO3 film has potential application in solid state refrigeration.•The electrocaloric effect in Pb1-xBaxHfO3 films is explained by Landau-Devonshire theory.
Summary
Aims
We tested the hypothesis that endothelial progenitor cell (EPC)‐mediated functional recovery after stroke may be associated with the endothelial nitric oxide synthase ...(eNOS)/brain‐derived neurotrophic factor (BDNF) signaling pathway.
Methods
Mice were infused with either EPCs or saline after being subjected to middle cerebral artery occlusion. The EPC‐treated mice also received intravenous injections of either Nω‐nitro‐l‐arginine methyl ester (L‐NAME, the NOS inhibitor) or saline.
Results
The activation of eNOS and the expression of BDNF were significantly increased in ischemic brain of the EPC‐treated mice, along with increased angiogenesis and neurogenesis. On diffusion tensor imaging (DTI), significant increases in fractional anisotropy and fiber count were observed in white matter, indicating axonal growth stimulated by EPCs. However, the EPC‐treated mice that were received an L‐NAME injection failed to exhibit the observed increases in angiogenesis, neurogenesis, and axonal growth. In addition, the neurons cocultured with EPCs in vitro exhibited the increased expression of BDNF and decreased apoptosis after oxygen–glucose deprivation compared with the control group. This EPC‐induced protective effect was virtually absent in the L‐NAME treatment group.
Conclusion
The eNOS/BDNF pathway may be involved in the EPC‐mediated functional recovery of stroke mice. DTI is feasible for dynamically tracking the orientation of axonal projections after EPC treatment.
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