Achieving large piezoelectric response and high Curie temperature, simultaneously, are of great demand but have been rarely achieved in BiFeO3-PbTiO3 (BF-PT) based morphotropic phase boundary (MPB) ...systems. In this work, in-situ synchrotron x-ray diffraction and transmission electron microscopy were carried out in BF-PT-0.19Ba(Zr,Ti)O3 high-temperature piezoceramic, a recently reported MPB composition with high piezoelectric coefficient, to elucidate the underlying structural mechanism. A field induced irreversible transition from tetragonal (T) P4mm phase to rhombohedral (R) R3c phase is identified although R and T phases are still coexisted after poling. This induces the significantly enhanced irreversible domain switching of both R and T phases and the reversible domain switching of R phase but only a slightly enhanced reversible switching of T phase of as compared with other BF-PT-x Ba(Zr,Ti)O3 MPB compositions, leading to the significant increase of lattice strain up to ∼0.15% but only a slightly increase of strain from extrinsic domain switching due to the strong coupling between lattice strain and domain switching in both R and T phases, although the strain contribution seems to be composition independent after the field induced irreversible phase transition. The present study demonstrates a new performance enhancement mechanism to design the high-performance BF-PT based high-temperature piezoelectric ceramics in terms of the different roles of R and T phases within MPB.
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Using the level-set method and the continuum interface model, the axisymmetric thermocapillary migration of gas bubbles in an immiscible bulk liquid with a temperature gradient at moderate to large ...Marangoni number is simulated numerically. Constant material properties of the two phases are assumed. Steady state of the motion can always be reached. The terminal migration velocity decreases monotonously with the increase of the Marangoni number due to the wrapping of isotherms around the front surface of the bubble. Good agreements with space experimental data and previous theoretical and numerical studies in the literature are evident. Slight deformation of bubble is observed, but no distinct influence on the motion occurs. It is also found that the influence of the convective transport of heat inside bubbles cannot be neglected at finite Marangoni number, while the influence of the convective transport of momentum inside bubbles may be actually negligible.
The current study was undertaken to investigate the time course of gastric ischemia-reperfusion (GI-R)-induced gastric mucosal injury and repair and whether extracellular signal-regulated kinase 1/2 ...(ERK1/2) were involved in GI-R-induced gastric mucosal injury and repair.
Immunohistochemistry and Western blot analyses were used.
Gastric mucosal injury induced by ischemia alone was mild. However, the injury worsened after reperfusion, reaching a maximum at 1 h, and was accompanied by increased apoptotic cells and decreased proliferative cells. Then, the gastric mucosal cells began to repair the injury by enhanced proliferation, which peaked at 24 h after reperfusion, and by 72 h the damaged gastric mucosa was mostly repaired. The ERK1/2 (nonactivated ERK1/2) protein expression level and distribution profile showed no significant changes during the entire reperfusion phase, but the p-ERK1/2 (activated ERK1/2) level changed dramatically. The p-ERK1/2 protein level was decreased at 0.5 h after reperfusion began, and then gradually increased, peaking after 3 h of reperfusion; these changes in p-ERK1/2 occurred simultaneously in the cytoplasm and nucleus. On the other hand, inhibition of the activation of ERK1/2, induced by PD98059, a specific ERK1/2 upstream inhibitor, aggravated the gastric mucosal injury, and apoptosis was increased and proliferation was reduced in the gastric mucosal cells after the same duration of reperfusion.
Serious gastric mucosal damage involving apoptotic cells occurred rapidly at an early stage of reperfusion and was closely related to the suppression of ERK1/2 activation. The activated ERK1/2 signaling transduction pathway played an important role. Activated ERK1/2 participated in the regulation of gastric mucosal injury and repair induced by GI-R, and might be mediated by the inhibition of apoptosis and the promotion of proliferation in gastric mucosal cells.
This study was aimed to investigate the characteristics and clinical significance of NOTCH1 mutation in adult T-cell acute lymphoblastic leukemia (T-ALL). Exon 26/N-terminal region of the ...heterodimerization domain (HD-N) , exon 27/ C-terminal region of the heterodimerization domain (HD-C) , exon 28 and exon 34/ proline-glutamic acid-serine-threonine (PEST) domain of the NOTCH1 gene were amplified, cloned and sequenced in 42 adult patients with T-ALL to identify the frequency, position and type of NOTCH1 mutation, their correlations with laboratorial and clinical parameters, as well as their relevant prognostic significance. The results showed that the frequency of NOTCH1 mutation in this cohort of adult patients was 66.7% (28/42); A total of 45 types of NOTCH1 mutations were identified in present study, most of them were in HD-N (48.9%, 22/45) and PEST (40.0%, 18/45) domains. Mutation in amino acid 1575 (L1575P) was the top one type of mutation in HD-N (25.0%, 7/28), and amino acid 2443 was the most common mu
Five new characteristic cembrane-type diterpenoids (olibacartiols A–E, 1–5) were acquired from the gum resin of Boswellia carterii. The structures of these diterpenoids were characterized by detailed ...spectroscopic analysis, and compounds 1–3 were unambiguously confirmed by single-crystal X-ray diffraction experiments. The anti-inflammatory activities of the isolated compounds were evaluated using LPS-induced BV2 cell model and compounds 2–5 showed moderate NO inhibitory effects with IC50 values of 8.84 ± 1.02, 9.82 ± 1.95, 9.75 ± 2.24, and 7.39 ± 1.24 μM, respectively.
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•Five undescribed cembrane-type diterpenoids were acquired from the gum resin of Boswellia carterii.•Their structures were characterized by spectroscopic analysis, ECD calculations, and X-ray diffraction experiments.•Compounds 2–5 showed moderate anti-inflammatory effects on LPS-induced BV2 cell.
Anodic oxidation of catechols
1a–
e in the presence of 5-methyl-2-mercapto-1,3,4-thiadiazole
2 has been studied in acetate buffer solution by cyclic voltammetry and controlled-potential electrolysis ...techniques. The effects of various electrolytic conditions (amount of passed charge, anodic materials, pH of the electrolytic solution, applied potential, and concentration of substrates) on the yield have also been investigated. The results showed that the position of the initial substituent of the starting catechol derivatives dominated the formation of monothiadiazol-2-ylthio-substituted or/and dithiadiazol-2-ylthio-substituted products. For 4-substituted catechols
1a–
b, monothiadiazol-2-ylthio-substituted products (
3a–
b) were exclusively produced in high to excellent yields. However, in the cases of catechol itself (
1c) and 3-substituted catechols (
1d–
e), both monothiadiazol-2-yl-substituted (
3c–
e and
5d–
e) and dithiadiazol-2-ylthio-substituted products (
4c–
e) were isolated. In addition, the nature of the initial substituent of the starting 3-substituted catechols (
1d and
1e) affected the relative ratio of the two monothiadiazol-2-ylthio-substituted isomers (
3d–
e vs
5d–
e).
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Infrared (IR) small dim target detection near the sea-sky line (SSL) is crucial for enhancing the early warning capability of maritime vehicles. However, the interferences caused by the strong ...contrast have not been properly addressed. Consequently, a specially designed algorithm regional-division local contrast measure (RDLCM) that focuses on the detection of IR small dim targets appearing near the SSL is proposed. First, an SSL detection module based on a lightweight convolutional neural network (CNN) is devised to achieve fast pixel-level SSL detection. Then, a set of regional-division windows (RDWs) are designed according to the strong grayscale contrast distribution around the SSL, and through the division of the effective regions, the RDWs could realize the potential extraction and refinement of the IR small dim targets that appear near the SSL. Experiments on three IR image sequences demonstrate that the proposed algorithm achieves the best detection accuracy among the classical and state-of-the-art algorithms in comparison and runs at 44 frames per second (FPS), which could meet real-time requirements. The code and dataset are available at RDLCM.
Here we describe a number of mostly isolated bird and non-avian dinosaur footprints from the Huangyangquan track site in the Lower Cretaceous Lower Layer of the Tugulu Group near Huangyangquan ...Reservoir in the Wuerhe District, Karamay, Xinjiang Uyghur Autonomous Region, China. Bird footprints at the site pertain to
Koreanaornis dodsoni n. ichnosp.,
Goseongornipes isp.,
Aquatilavipes isp., and
Moguiornipes robusta n. ichnogen. n. ichnosp.
Moguiornipes tracks may be the products of a bird with lobed feet. These shorebird-morph tracks are the first solid evidence of birds in the Tugulu Group, and greatly enrich the known faunal diversity of the Lower Layer of the Tugulu Group. The Huangyangquan avian ichnofauna is comparable to those of the Jindong Formation, Korea and the Dakota Formation, USA. Non-avian dinosaur footprints at the site pertain to cf.
Jialingpus isp.,
Asianopodus isp., and
Kayentapus isp. This is the first report of
Jialingpus from Lower Cretaceous strata. The discoveries of
Asianopodus isp. and
Kayentapus isp. increase the known ranges of these two ichnogenera.
To investigate the effects of aerobic exercise and starvation on growth performance, postprandial metabolic response and their interaction in a sedentary fish species, either satiation-fed or starved ...juvenile southern catfish (Silurus meridionalis) were exercised at 25°C under three water velocities, i.e., nearly still water (control), 1 body length (bl) s−1 and 2 bl s−1, for eight weeks. Then, the feed intake (FI), food conversion efficiency (FCE), specific growth rate (SGR), morphological parameters, resting ṀO2 (ṀO2rest) and postprandial ṀO2 responses of the experimental fish were measured. Exercise at a low velocity (1 bl s−1) showed no effect on any growth performance parameter, whereas exercise at a high velocity (2 bl s−1) exhibited higher FI but similar SGR due to the extra energy expenditure from swimming and consequent decreased FCE. Starvation led to a significant body mass loss, whereas the effect intensified in both exercise groups. Exercise resulted in improved cardio-respiratory capacity, as indicated by increased gill and heart indexes, whereas it exhibited no effect on resting and postprandial metabolism in S. meridionalis. The starved fish displayed significantly larger heart, gill and digestive tract indexes compared with the feeding fish, suggesting selective maintenance of cardio-respiratory and digestive function in this fish species during starvation. However, starved fish still exhibited impaired digestive performance, as evidenced by the prolonged duration and low postprandial metabolic increase, and this effect was further exacerbated in both the 1 and 2 bl s−1 exercise groups. These data suggest the following: (1) aerobic exercise produced no improvement in growth performance but may have led to the impairment of growth under insufficient food conditions; (2) the mass of different organs and tissues responded differently to aerobic exercise and starvation due to the different physiological roles they play; and (3) aerobic exercise had no effect on the postprandial metabolic response under a “normal feeding” situation, whereas it may have resulted in the impairment of the digestive capacity when food availability was low due to the competition of energy and oxygen under unfavorable conditions in juvenile S. meridionalis.
The bacterial diversity in saline-alkali ponds rearing common carp was investigated using the 16S rRNA gene clone library technique. Phylogenetic analysis of the most common and dominant sequences ...recovered indicated that these sequences fell into the following major lineages, including Proteobacteria (α-, β-, γ-), Actinobacteria, Cyanobacteria, Planctomycetes, Fibrobacteres, Bacteroidetes, Chloroflexi, and unclassified bacteria. Sequence analysis showed that the bacterial diversity was abundant, and the sequences belonging to β-Proteobacteria, α-Proteobacteria and Actinobacteria were predominant. The most sequences in the saline-alkali rearing ponds exhibited low similarity with known bacterial 16S rRNA genes, suggesting that these sequences may represent novel bacteria. In addition, the majority of our sequences were most closely affiliated with sequences retrieved from inland waters of China. These results suggest that the saline-alkali ponds rearing common carp are specific ecologic niches and the distribution of the bacteria may be influenced by geographical factors. This study reports the bacterial diversity in saline-alkali ponds rearing common carp by the culture-independent technique for the first time; therefore, it provides important information for understanding the microbial ecology in saline-alkali rearing ponds and managing the microbial community composition to promote and maintain the health of aquaculture environments.
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