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Wogonin is a natural flavone compound from the plant Scutellaria baicalensis, which has a variety of pharmacological activities such as anti-cancer, anti-virus, anti-inflammatory, and immune regulation. However, the potential mechanism of wogonin remains unknown. This study was to confirm the molecular mechanism of wogonin for acute monocytic leukemia treatment, known as AML-M5. The potential action targets between wogonin and acute monocytic leukemia were predicted from databases. The compound-target-pathway network and protein-protein interaction network (PPI) were constructed. The enrichment analysis of related targets and molecular docking were performed. The network pharmacological results of wogonin for AML-M5 treatment were verified using the THP-1 cell line. 71 target genes of wogonin associated with AML-M5 were found. The key genes TP53, SRC, AKT1, RELA, HSP90AA1, JUN, PIK3R1, and CCND1 were preliminarily found to be the potential central targets of wogonin for AML-M5 treatment. The PPI network analysis, GO analysis and KEGG pathway enrichment analysis demonstrated that the PI3K/AKT signaling pathway was the significant pathway in the wogonin for AML-M5 treatment. The antiproliferative effects of wogonin on THP-1 cells of AML-M5 presented a dose-dependent and time-dependent manner, inducing apoptosis, blocking the cell cycle at the G2/M phase, decreasing the expressions of CCND1, CDK2, and CyclinA2 mRNA, as well as AKT and p-AKT proteins. The mechanisms of wogonin on AML-M5 treatment may be associated with inhibiting cell proliferation and regulating the cell cycle via the PI3K/AKT signaling pathway. [ABSTRACT FROM AUTHOR]

Enhancing the reliability of inversion results has always been a prominent issue in the field of geophysics. In recent years, data-driven inversion methods leveraging deep neural networks (DNNs) have gained prominence for their ability to address non-uniqueness issues and reduce computational costs compared to traditional physically model-driven methods. In this study, we propose a GMNet machine learning method, i.e., a CNN-based inversion method for gravity and magnetic field data. This method relies more on data-driven training, and in the prediction phase after the model is trained, it does not heavily depend on a priori assumptions, unlike traditional methods. By forward modeling gravity and magnetic fields, we obtain a substantial dataset to train the CNN model, enabling the direct mapping from field data to subsurface property distribution. Applying this method to synthetic data and one-field data yields promising inversion results. [ABSTRACT FROM AUTHOR]

C48H68Cl4N8O8Ni4, tetragonal, I41/a (no. 88), a = 16.9137(5) Å, c = 19.5028(13) Å, V = 5579.2(5) Å3, Z = 4, Rgt(F) = 0.0391, wRref(F2) = 0.1221, T = 293 K. [ABSTRACT FROM AUTHOR]

Ammonium and polyamines are essential nitrogen metabolites in all living organisms. Crosstalk between ammonium and polyamines through their metabolic pathways has been demonstrated in plants and animals, while no research has been directed to explore this relationship in algae or to investigate the underlying molecular mechanisms. Previous research demonstrated that high concentrations of ammonium and putrescine were among the active substances in bacteria-derived algicide targeting dinoflagellates, suggesting that the biochemical inter-connection and/or interaction of these nitrogen compounds play an essential role in controlling these ecologically important algal species. In this research, putrescine, ammonium, or a combination of putrescine and ammonium was added to cultures of three dinoflagellate species to explore their effects. The results demonstrated the dose-dependent and species-specific synergistic effects of putrescine and ammonium on these species. To further explore the molecular mechanisms behind the synergistic effects, transcriptome analysis was conducted on dinoflagellate Karlodinium veneficum treated with putrescine or ammonium vs. a combination of putrescine and ammonium. The results suggested that the synergistic effects of putrescine and ammonium disrupted polyamine homeostasis and reduced ammonium tolerance, which may have contributed to the cell death of K. veneficum. There was also transcriptomic evidence of damage to chloroplasts and impaired photosynthesis of K. veneficum. This research illustrates the molecular mechanisms underlying the synergistic effects of the major nitrogen metabolites, ammonium and putrescine, in dinoflagellates and provides direction for future studies on polyamine biology in algal species. [ABSTRACT FROM AUTHOR]

Aims: HNF1B syndrome is caused by defects in the hepatocyte nuclear factor 1B (HNF1B) gene, which leads to maturity‐onset diabetes of the young type 5 and congenital organ malformations. This study aimed to identify a gene defect in a patient presenting with diabetes and severe diarrhea, while also analyzing the prevalence of hypomagnesemia and its correlation with the HNF1B genotype. Materials and Methods: Whole exome sequencing was used to identify responsible point mutations and small indels in the proband and their family members. Multiplex ligation‐dependent probe amplification was carried out to identify HNF1B deletions. Furthermore, an analysis of published data on 539 cumulative HNF1B cases, from 29 literature sources, was carried out to determine the correlation between the HNF1B genotype and the phenotype of serum magnesium status. Results: Using multiplex ligation‐dependent probe amplification, we identified a de novo heterozygous HNF1B deletion in the patient, who showed dorsal pancreas agenesis and multiple kidney cysts, as detected by magnetic resonance imaging. Magnesium supplementation effectively alleviated the symptoms of diarrhea. Hypomagnesemia was highly prevalent in 192 out of 354 (54.2%) patients with HNF1B syndrome. Compared with patients with intragenic mutations, those with HNF1B deletions were more likely to suffer from hypomagnesemia, with an odds ratio of 3.1 (95% confidence interval 1.8–5.4). Conclusions: Hypomagnesemia is highly prevalent in individuals with HNF1B syndrome, and those with HNF1B deletion are more susceptible to developing hypomagnesemia compared with those with intragenic mutations. The genotype–phenotype associations in HNF1B syndrome have significant implications for endocrinologists in terms of genotype detection, treatment decisions and prognosis assessment. [ABSTRACT FROM AUTHOR]

Environmental barrier coatings (EBCs) are crucial to the reliability and durability of SiCf/SiC composite components seeking applications in hot sections of next‐generation advanced aero‐engines. The cracks initiated and developed in EBCs owing to various reasons during service greatly undermine their lifespans. To address this problem, in this work, silicon carbide (SiC) in the forms of particles and whiskers with various amounts have been introduced to ytterbium disilicate (Yb2Si2O7), the mainstream EBC topcoat materials, so as to gain some self‐healing potential. The results reveal that, the SiC inclusions in Yb2Si2O7 in the presence of ytterbium monosilicate (Yb2SiO5) can trigger the following reactions. Specifically, SiC self‐healing agents are oxidized to form viscous SiO2, which actively reacts with Yb2SiO5 upon encountering it, forming Yb2Si2O7. This has brought twofold beneficial effects including ① silicon supplementation of disilicate topcoat, whose silicon element tends to be "dragged out" by water vapor, leading to the deterioration of thermal mismatch; as well as ② crack self‐healing resulting from the volume expansion induced by the above reactions. Then the two aspects of self‐healing agents, namely the "promptness" and "sustainability," have been discussed in detail. The former is unveiled to be more pertinent to the repairing of large cracks, whilst the latter is more relevant to the self‐healing of tiny cracks at initiation or early stage of propagation. The current work sheds some lights on the design and development of more durable and robust EBCs with self‐healing capability. [ABSTRACT FROM AUTHOR]

C18H15N7O4Zn, triclinic, P 1 ‾ (no. 2), a = 9.1100(8) Å, b = 10.6451(7) Å, c = 12.0479(8) Å, α = 95.238(5)∘, β = 112.154(7)∘, γ = 112.971(7)∘, V = 956.56(13) Å3, Z = 2, Rgt(F) = 0.0264, wRref(F2) = 0.0731, T = 298 K. [ABSTRACT FROM AUTHOR]

Background: The incidence of incidental pulmonary embolism (IPE) has greatly increased, but its clinical characteristics and outcomes are still controversial. This study aimed to compare the clinical characteristics and outcomes between cancer patients with IPE and patients with symptomatic pulmonary embolism (SPE). Patients/Methods: Clinical data of 180 consecutive patients with cancer complicated with pulmonary embolism admitted to Beijing Cancer Hospital from July 2011 to December 2019 were retrospectively collected and analysed. General characteristics, diagnosis time of pulmonary embolism (PE), location of PE, concurrent deep venous thrombosis, anticoagulant treatment, impact of PE on anti-tumor treatment, recurrent venous thromboembolism, rate of bleeding after anticoagulation therapy, survival and risk factors of IPE were compared with SPE. Results: Of 180 patients, 88 (49%) had IPEs and 92 (51%) had SPEs. Patients with IPE and SPE did not differ in age, sex, tumor type, or tumor stage. Median diagnosis times of IPE and SPE after cancer were 108 (45, 432) days and 90 (7, 383) days, respectively. Compared to SPE, IPE tended to be central (44% versus 26%; P < 0.001), isolated (31.8% versus 0.0%; P < 0.001), and unilateral (67.1% versus 12.8%; P < 0.00). The rate of bleeding after anticoagulation therapy did not differ between IPE and SPE. Patients with IPE had a better prognosis than patients with SPE in terms of 30-, and 90-day mortality, as well as overall survival after diagnosis of PE (median: 314.5 vs. 192.0 days, log-rank P = 0.004) and cancer (median: 630.0 vs. 450.5 days, log-rank P = 0.018). SPE (compared to IPE) was an independent risk factor for poor survival after diagnosis of PE in multivariate analysis (hazard ratio [HR] = 1.564, 95% confidence interval [CI]: 1.008–2.425, p = 0.046). Conclusions: IPE accounts for nearly one half of PE cases among Chinese cancer patients. With active anticoagulation treatment, IPE is expected to achieve better survival rates than SPE. [ABSTRACT FROM AUTHOR]

The protection effects of an environmental barrier coating (EBC) consisting of silicon bond coat and mixed ytterbium monosilicate and ytterbium disilicate composite topcoat are directly evaluated by measuring the strength retention rate of SiCf/SiC composites completely wrapped up by the previous EBCs after soaking in a mixed oxygen and water vapor environment at 1300°C for up to 200 h. The results show that the mixed topcoat exhibits not only extremely excellent phase stability but also fantastic protection effects toward composites. After 200 h of corrosion, the fully protected composites are unveiled to present not only dramatically reduced weight gain ratios, less than.6%, compared to ∼10% for those unprotected ones, but also extremely higher strength retention rates, more than 90%, compared to only 10%–15% for those unprotected ones. Further, the fully protected composites show a quasi‐ductile load versus displacement curve, suggesting the retention of the oxidation‐prone pyrolytic carbon interphase of current composites. [ABSTRACT FROM AUTHOR]

Implicit staggered-grid finite-difference (SGFD) methods are widely used for the first-order acoustic wave-equation modeling. The identical implicit SGFD operator is commonly used for all of the first-order spatial derivatives in the first-order acoustic wave-equation. In this paper, we propose a hybrid explicit implicit SGFD (HEI-SGFD) scheme which could simultaneously preserve the wave-equation simulation accuracy and increase the wave-equation simulation speed. We use a second-order explicit SGFD operator for half of the first-order spatial derivatives in the first-order acoustic wave-equation. At the same time, we use the implicit SGFD operator with added points in the diagonal direction for the other first-order spatial derivatives in the first-order acoustic wave-equation. The proposed HEI-SGFD scheme nearly doubles the wave-equation simulation speed compared to the implicit SGFD schemes. In essence, the proposed HEI-SGFD scheme is equivalent to the second-order FD scheme with ordinary grid format. We then determine the HEI-SGFD coefficients in the time–space domain by minimizing the phase velocity error using the least-squares method. Finally, the effectiveness of the proposed method is demonstrated by dispersion analysis and numerical simulations. [ABSTRACT FROM AUTHOR]

Purpose: This study explores how paternalistic leadership (PL) influences Chinese expatriates' work engagement in a cross-cultural context, and examines how expatriates' cross-cultural adaptability sets a boundary condition for this relationship. Design/methodology/approach: Data were collected from two-wave surveys of 82 supervisors and 318 Chinese expatriate teachers from 57 Confucius Institutes in 18 countries. Structural equation modeling was used to test the hypothesized relationships. Findings: Benevolent and moral leadership as job resources are negatively related to work–family conflict (WFC), whereas the job demand of authoritarian leadership positively relates to WFC. Further, WFC mediates the effect of PL styles on Chinese expatriates' work engagement. Cross-cultural adaptability moderates the negative relationship between WFC and work engagement, and the indirect effect of PL styles on work engagement through WFC. Practical implications: Organizations should consider WFC an important intervening mechanism linking PL and Chinese expatriates' work engagement. Cross-cultural organizations can mitigate the negative impact of WFC on work engagement by enhancing expatriates' cross-cultural adaptability. Originality/value: This study is the first to examine the PL–work engagement relationship via a work–family interface, which contributes to integrating leadership and work–family outcomes. It enriches research on the JD-R model by showing that job resources and job demands affect employee outcomes through the mediation of stressors. Furthermore, this study identifies a new personal resource by examining cross-cultural adaptability's moderating role. [ABSTRACT FROM AUTHOR]

In this study, PyC coating with different thickness was prepared on SiC fibers via chemical vapor deposition method. Uncoated and PyC coated SiC fibers were heat treated in Ar atmosphere under different annealing condition. The effects of PyC coating on the mechanical properties of SiC fibers at room temperature were investigated. The morphology, composition, structure and mechanical properties of SiC fibers after high temperature treatment were also studied. The results showed that PyC coating could reduce the dispersion of tensile strength for SiC fibers. Weibull modulus increased from 4.19 (SiC fiber) to 5.59 (PyC700 fiber), while the tensile strength decreased a little with the increment of PyC coating thickness. Furthermore, PyC coating could remarkably retard Si sublimation from SiC fiber at high temperature. Uncoated SiC fiber was converted to porous pure-carbon fiber after being annealed at 2000 °C for 5 h, while PyC700 fiber still showed relative dense SiC core after the same treatment. To a certain extent, the inhibition ability was improved with increment of PyC coating thickness. In addition, PyC coated SiC fibers could maintain more tensile strength after being annealed at 1800 °C for 1 h. The tensile strength retention of uncoated SiC fiber was 27.3%, while that of PyC700 fiber could reach up to 43.2%. [ABSTRACT FROM AUTHOR]

A bi-layer environmental barrier coating (EBC) consisting of silicon(Si) bond coat/mixed ytterbium disilicate (Yb 2 Si 2 O 7) and ytterbium monosilicate (Yb 2 SiO 5) topcoats has been successfully prepared to completely wrap up the SiC f /SiC composites and the protective effects of such EBC have been evaluated by soaking them in a mixed 50% O 2 and 50% H 2 O corrosive gases at 1300 °C for various times. In topcoats, Yb 2 Si 2 O 7 is the major phase, providing good thermal expansion coefficient (CTE) matching with composite substrate and thus excellent thermal shock resistance, whereas Yb 2 SiO 5 is the dispersing minor phase, providing improved water vapor corrosion resistance. The completely wrapping up of SiC f /SiC composites by above EBC system is employed to avoid direct exposure to the corrosive conditions, making it possible to evaluate the genuine protection effects of current EBCs. Under 1300 °C water vapor corrosion, the mass change, the phase composition and the evolution of microstructure are investigated, which suggest that the bi-layer EBC has excellent performance on protecting SiC f /SiC composites from water vapor corrosion at 1300 °C. [ABSTRACT FROM AUTHOR]

The poor fracture toughness of La2Zr2O7 severely limits its application as a high temperature thermal barrier coating topcoat material. To toughen it, a ferroelastic second phase, NdAlO3, with a Curie temperature of 1367°C has been introduced to form x NdAlO3/(1‐x) La2Zr2O7 composite ceramics by a spark plasma sintering technique, where x = 10, 20, 30, 40, and 50 mol%. The fracture toughness of sintered composite ceramic compacts is measured at both room temperature and 1200°C, respectively, by a single‐edge‐notch beam test method. The results show that, at room temperature, the residual compressive stress in the La2Zr2O7 matrix plays an important role in the toughening of composite ceramics. By eliminating this factor, the remaining toughening effects agree with the measured fracture toughness at 1200°C, suggesting that the other toughening is probably ferroelastic domain switching toughening and that it is still valid at high temperature. Furthermore, the toughening effect arising from ferroelastic domain switching is governed by the overall domain switching zone, which is determined by both individual domain switching zone width and the "concentration" of ferroelastic phases. A relatively high coercive stress of NdAlO3 and relatively low residual tensile stress in NdAlO3 second phases contribute to negligible influence of residual tensile stress on domain switching zone width, leading to the continuous increase of fracture toughness of composite ceramics with more NdAlO3 added at room temperature. [ABSTRACT FROM AUTHOR]

C23H14Cl4N6O4, triclinic, P1̄ (no. 2), a = 9.044(2) Å, b = 11.340(2) Å, c = 11.812(3) Å, α = 95.470(17)°, β = 105.46(2)°, γ = 90.084(18)°, V = 1161.8(5) Å3, Z = 2, Rgt(F) = 0.0914, wRref(F2) = 0.2547, T = 296 K. [ABSTRACT FROM AUTHOR]

Acemetacin (ACM) is a new non-steroidal anti-inflammatory drug with anti-inflammatory, analgesic, and antipyretic effects. However, the poor water solubility and gastrointestinal side effects limit its use. Recently, the co-amorphous (CAM) strategy has attracted great interest to improve solubility for poorly water-soluble drugs, and basic amino acids have the potential to protect the gastrointestinal tract. In order to develop a highly efficient and low-toxic ACM formulation, we prepared ACM CAM systems, with basic amino acids (lysine, arginine, and histidine) as co-formers, using a cryo-milling method. The solid-state behaviors of the ACM CAM systems were characterized by polarizing light microscopy, differential scanning calorimetry, and powder X-ray diffraction. Fourier transform infrared spectroscopy and molecular docking were carried out to understand the formation mechanism. Moreover, the gastro-protective effects of ACM CAM systems were evaluated in a rat gastric ulcer model. The results demonstrated that the CAM systems improved the dissolution rates of ACM compared with the neat amorphous counterpart. Furthermore, ACM CAM systems are significantly effective in mitigating the ACM-induced gastric ulcer in rats, and the ulcer inhibition rates were almost 90%. More importantly, this study provided a useful method for mitigating drug-induced gastrointestinal damage and broadened the applications of drug–amino acid CAM systems. [ABSTRACT FROM AUTHOR]

Infertility rates for both females and males have increased continuously in recent years. Currently, effective treatments for male infertility with defined mechanisms or targets are still lacking. G protein-coupled receptors (GPCRs) are the largest class of drug targets, but their functions and the implications for the therapeutic development for male infertility largely remain elusive. Nevertheless, recent studies have shown that several members of the GPCR superfamily play crucial roles in the maintenance of ion-water homeostasis of the epididymis, development of the efferent ductules, formation of the blood-epididymal barrier and maturation of sperm. Knowledge of the functions, genetic variations and working mechanisms of such GPCRs, along with the drugs and ligands relevant to their specific functions, provide future directions and a great arsenal for new developments in the treatment of male infertility. [ABSTRACT FROM AUTHOR]

The mechanical and thermophysical properties of Xenotime-type REPO4 (RE = Lu, Yb, Er, Y and Sc) have been theoretically and experimentally investigated for a potential environmental barrier coating (EBC) topcoat application. The results show that the current studied REPO4 exhibits a quasi-ductile property, suggesting a potential long life expectancy of its made coatings. Further, from the study of underlying parameters governing thermophysical properties of a ceramic, low thermal expansion coefficients (TECs) and low thermal conductivities cannot be achieved simultaneously, due to mutual exclusive nature of above two parameters. REPO4 has been unveiled to have rather small TECs, attributing partly to its weak lattice anharmonicity, and is thus well-matched with silicon carbide based ceramic matrix composites. Last, the current investigated REPO4 exhibits very good high-temperature water vapor corrosion resistance, excellent calcium-magnesium aluminosilicates (CMAS) resistance as well as excellent chemical compatibility with silicon bond coats at elevated temperatures. Therefore, the Xenotime-type rare earth phosphates are a promising EBC topcoat material. [ABSTRACT FROM AUTHOR]

The susceptibility of newly expressed proteins to digestion by gastrointestinal proteases (e.g., pepsin) has long been regarded as one of the important endpoints in the weight-of-evidence (WOE) approach to assess the allergenic risk of genetically modified (GM) crops. The European Food Safety Authority (EFSA) has suggested that current digestion study protocols used for this assessment should be modified to more accurately reflect the diverse physiological conditions encountered in human populations and that the post-digestion analysis should include analytical methods to detect small peptide digestion products.The susceptibility of two allergens (beta-lactoglobin (β-Lg) and alpha-lactalbumin (α-La)) and two non-allergens (hemoglobin (Hb) and phosphofructokinase (PFK)) to proteolytic degradation was investigated under two pepsin digestion conditions (optimal pepsin digestion condition: pH 1.2, 10 U pepsin/μg test protein; sub-optimal pepsin digestion condition: pH 5.0, 1 U pepsin/10 mg test protein), followed by 34.5 U trypsin/mg test protein and 0.4 U chymotrypsin/mg test protein digestion in the absence or presence of bile salts. All samples were analyzed by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) in conjunction with Coomassie Blue staining and, in parallel, liquid chromatography tandem mass spectrometry (LC-MS) detection. The results provide following insights: 1) LC-MS methodology does provide the detection of small peptides; 2) Peptides are detected in both allergens and non-allergens from all digestion conditions; 3) No clear differences among the peptides detected from allergen and non-allergens; 4) The differences observed in SDS-PAGE between the optimal and sub-optimal pepsin digestion conditions are expected and align with kinetics and properties of the specific enzymes; 5) The new methodology with new digestion conditions and LC-MS detection does not provide any differentiating information for prediction whether a protein is an allergen. The classic pepsin resistance assay remains the most useful assessment of the potential exposure of an intact newly expressed protein as part of product safety assessment within a WOE approach. [ABSTRACT FROM AUTHOR]

Purpose: This study proposes a moderated mediation model that examines the roles that openness to change and psychological capital (PsyCap) may play in the relationship between climate for innovation and employee creativity. Design/methodology/approach: Path modeling analysis with software Mplus 7 is conducted to test our moderated mediation model. Findings: The results show that climate for innovation promotes openness to change, which in turn encourages employee creativity, and PsyCap moderates not only the relationship between climate for innovation and openness to change but also the indirect effect of climate for innovation on employee creativity through openness to change. Research limitations/implications: Although we attempt to avoid common method bias by collecting data in two waves, the six-month time interval separating the two waves of data collection may not be long enough to detect the causal relationship between climate for innovation and employee creativity. In addition, this study is conducted in companies located in China, which may raise the question of generalizability to other cultures. Originality/value: The main contribution is building a moderated mediation model to uncover the potential mediating mechanism and boundary conditions associated with the influence of climate for innovation on employee creativity. [ABSTRACT FROM AUTHOR]

Estimating subsurface attenuation distribution is essential to compensate the amplitude and phase distortions in seismic imaging and characterize attenuative reservoirs. Full-waveform inversion (FWI) methods represent promising techniques to invert for both velocity and attenuation models with arbitrary spatial distributions. However, simultaneously determining velocity and attenuation properties introduces the problem of interparameter trade-off in viscoelastic FWI. Ignoring attenuation effects can result in inaccurate velocity estimations. Velocity errors may produce significant parameter crosstalk artefacts in the inverted attenuation models. An appropriate misfit function measuring specific seismic attribute is essential to capture the influence of attenuation on the seismic data and thus is expected to reduce the influences of velocity errors for attenuation estimation. In this study, we evaluate the performances of different misfit functions for attenuation estimation in viscoelastic FWI accompanied with a two-stage sequential inversion strategy. Synthetic examples with different acquisition surveys are given to show that in the presence of strong velocity errors, the amplitude-based misfit functions, including envelope-difference, root-mean-square amplitude-ratio and spectral amplitude-ratio, can invert for the attenuation models more reliably, compared to the waveform-difference and instantaneous phase misfit functions. With the two-stage inversion approach, more reliable velocity and attenuation models can be obtained using viscoelastic FWI. [ABSTRACT FROM AUTHOR]

During tensile deformation, nanostructured (NS) metals often fail soon after yielding by forming a localized shear band. Here we report the observation of high density of shear bands that are homogeneously dispersed in the NS layer of a gradient Ni sample. These shear bands were nucleated at early elastic/plastic strain stage, reached number saturation at ∼3% strain, and remained arrested by the central coarse-grained (CG) matrix during the entire plastic deformation, resulting in a uniform tensile plasticity comparable to that of CG matrix. The formation of dispersed shear bands was promoted by the elastic/plastic interaction between NS surface layer and CG matrix, and affected by the surface roughness and the hardness variation in the NS surface layer. The width of shear bands remained constant, but the intensity of strain accumulation increased almost linearly with applied tensile strain, suggesting a stable shear banding process. Microstructure examination revealed that the strain in shear bands was accommodated by mechanically driven grain boundary migration and grain coarsening. These results clarify the fundamental questions: why/how does the NS layer supported by CG matrix achieve large uniform elongation? Moreover, the findings demonstrate the possibility of activating dispersed stable shear bands by synthesizing gradient architecture for optimized mechanical performances, i.e., a new strategy for evading the strength-ductility tradeoff in NS metals. Image 1 • Questions 'why/how does the NS layer supported by CG matrix achieve large uniform elongation?' are clarified. • Dense shear bands are homogeneously dispersed in the NS layer of gradient Ni. • Shear bands evolved stably during deformation, resulting in large uniform elongation. • Elastic/plastic interaction between NS and CG layers promoted the nucleation of shear bands. • Strain in shear bands is accommodated by mechanically driven grain coarsening. [ABSTRACT FROM AUTHOR]

In this paper the long-term oxidation resistance of SiC f /SiC composites manufactured by a single PIP technique and a hybrid CVI-PIP technique at 1200 °C in a static air has been systematically studied. It has been found that after oxidation at 1200 °C for 200 h, SiC f /SiC composites by the hybrid CVI-PIP technique can retain flexural strength as high as 76% and still exhibit a typical quasi-plastic fracture. In contrast, after oxidation for 100 h, SiC f /SiC composites produced by the single PIP technique can only keep 31.8% of their initial flexural strength and demonstrate a typical brittle fracture. An insertion of a dense and crystalline CVI derived SiC layer between fibers/interphase and PIP derived matrix makes the difference. To be specific, for those single PIP derived composites, i.e. without this CVI SiC layer, the fibers/interphase are totally exposed to oxidative environments due to the nature of PIP derived matrix that is porous and full of micro-cracks. Worse still, the oxidized products of PIP derived matrix, viscous and sticky SiO 2 , tends to tightly wrap up fibers, forming a strong fiber/matrix bond. On the contrary, for those hybrid CVI-PIP derived composites, the dense CVI SiC layer serves as an oxidation barrier, not only blocking the inward flowing of oxygen to invade interphase/fibers, but also precluding the viscous and sticky SiO 2 reach fiber surface. The superior properties of SiC f /SiC composites produced by hybrid CVI-PIP technique suggest it be a desirable manufacture technique for industrial applications. [ABSTRACT FROM AUTHOR]

Abstract The yttrium heavily doped La 2 Zr 2 O 7 solid solutions coatings, with a Y to La molar ratio of 1:1, have been successfully prepared by air plasma spraying technique. The evolution of phase composition, phase structure and thermal conductivity of such coatings with annealing at 1300 °C has been investigated. The results show that, a single pyrochlore structure can be retained for coating after annealing up to 48 h, beyond which the fluorite phase begins to precipitate out. By comparing thermal conductivities to those undoped counterparts at a similar porosity level, we find a considerably flat thermal conductivity versus temperature (k-T) curve, suggesting the existence of a strong phonon scattering source, which is inferred as rattlers. In addition, after the segmentation of the fluorite phase, the thermal conductivity of corresponding coatings rises considerably, indicating that the fluorite phase has a higher thermal conductivity than that of pyrochlore phase. Moreover, while the as-sprayed coatings show a clear indication of radiative thermal conduction beyond 1000 °C, the thermal conductivity of annealed coatings do not show such an uprising trend after 1000 °C, suggesting that the radiative thermal conduction has been greatly suppressed. The reason is proposed as the formation of local dipoles due to local enrichment of certain elements influences the propagation of electromagnetic waves and thus suppresses the radiative thermal conduction. [ABSTRACT FROM AUTHOR]

Aims/Introduction: Genetic and epigenetic mechanisms have been implicated in the pathogenesis of type 1 diabetes, and histone acetylation is an epigenetic modification pattern that activates gene transcription. However, the genome‐wide histone H3 acetylation in new‐onset type 1 diabetes patients has not been well described. Accordingly, we aimed to unveil the genome‐wide promoter acetylation profile in CD4+ T lymphocytes from type 1 diabetes patients, especially for those who are glutamate decarboxylase antibody‐positive. Materials and Methods: A total of 12 patients with new‐onset type 1 diabetes who were glutamate decarboxylase antibody‐positive were enrolled, and 12 healthy individuals were recruited as controls. The global histone H3 acetylation level of CD4+ T lymphocytes from peripheral blood was detected by western blot, with chromatin immunoprecipitation linked to microarrays to characterize the promoter acetylation profile. Furthermore, we validated the results of particular genes from chromatin immunoprecipitation linked to microarrays by using chromatin immunoprecipitation quantitative polymerase chain reaction, and analyzed the transcription level by real‐time quantitative polymerase chain reaction. Results: Elevated global histone H3 acetylation level was observed in type 1 diabetes patients, with 607 differentially acetylated genes identified between type 1 diabetes patients and controls by chromatin immunoprecipitation linked to microarrays. The hyperacetylated genes were enriched in biological processes involved in immune cell activation and inflammatory response. Gene‐specific assessments showed that increased transcription of inducible T‐cell costimulator was in concordance with the elevated acetylation in its gene promoter, along with positive correlation with glutamate decarboxylase antibody titer in type 1 diabetes patients. Conclusions: The present study generates a genome‐wide histone acetylation profile specific to CD4+ T lymphocytes in type 1 diabetes patients who are glutamic acid decarboxylase antibody‐positive, which is instrumental in improving our understanding of the epigenetic involvement in autoimmune diabetes. Patients with type 1 diabetes displays a distinct histone H3 acetylation profile in gene promoters in CD4+ T lymphocytes. Elevated histone H3 acetylation is associated with genes involving in T lymphocyte activation. GAD antibody production in T1D patients was associated with the hyperacetylation and increased expression of co‐stimulator ICOS. [ABSTRACT FROM AUTHOR]

The poor fracture toughness limits the wide application of the cubic lanthanum zirconate (La 2 Zr 2 O 7 ) ceramics. The current study reports a dramatic fracture toughness improvement of lanthanum zirconates by the introduction of lanthanum aluminates (LaAlO 3 ), a ferroelastic second phase. A composite ceramic with the composition of x LaAlO 3 / (1- x ) La 2 Zr 2 O 7 , where x  = 10, 20, 30, 40, 50 mol%, has been fabricated by a spark plasma sintering method. It is found that, the ferroelastic domains of LaAlO 3 in x LaAlO 3 /(1- x )La 2 Zr 2 O 7 composite ceramics clearly switch towards a direction that is normal to a propagating crack. In addition, the processing zone width of ferroelastic domains is found to decrease with an increase of LaAlO 3 inclusion, attributing to that the residual tensile stress in LaAlO 3 caused by the thermal expansion coefficient mismatch, which helps to expand the processing zone, decreases with more LaAlO 3 included. [ABSTRACT FROM AUTHOR]

• An optimum grain size (d o p t i m u m) on the order of a few micrometers exist ubiquitously for strength-ductility synergy, at which the strain energy density limit reaches a maximum while maintaining high yield strength. • Theoretical models on the grain size-dependence of uniform elongation and ultimate strength are developed, which accurately predict the d o p t i m u m. • The d o p t i m u m ≈ 2 l G b a r , where l G b a r ≈ k H P R 3 / 2 2 M G b is the characteristic width of grain boundary affected region. • The d o p t i m u m is the critical grain size having the strongest intragranular plastic strain gradient effect. • The d o p t i m u m is the limiting dimension that allows toughening by grain refinement. A strength-ductility trade-off usually occurs when grains are refined to increase strength. A question arises on if there exists a grain size for the best strength-ductility combination, i.e., with the highest possible strain energy density limit and strength simultaneously. This issue is crucial for guiding the design of strong and tough structural materials. Here we reveal an optimum grain size (d o p t i m u m) on the order of a few micrometers, at which the strain energy density limit, estimated as the product of strength and uniform elongation, reaches a maximum while maintaining reasonably high yield strength. The d o p t i m u m is found to exist in a series of single-phase FCC, BCC and HCP materials, indicating it as a universal phenomenon. Theoretical models on the grain size-dependence of uniform elongation and ultimate strength are developed by considering dislocation accumulation in grain boundary affected region (Gbar) and grain interior based on the classical Kocks-Mecking-Estrin model. Combined with the Hall-Petch relationship, the models accurately predict the d o p t i m u m. Importantly, the models disclose this d o p t i m u m to be close to twice of the characteristic width of Gbar (l G b a r), suggesting that it is exactly at or near the critical grain size with the strongest intragranular strain gradient effects. [Display omitted] [ABSTRACT FROM AUTHOR]

Fungal endophytes are well-known for their ability to promote plant growth and hinder fungal diseases, including Fusarium head blight (FHB) caused by Fusarium graminearum. This study aimed to characterize the biocontrol efficacy of strain J4-3 isolated from the stem of symptomless wheat collected from Heilongjiang Province, China. It was identified as Epicoccum layuense using morphological characteristics and phylogenetic analysis of the rDNA internal transcribed spacer (ITS) and beta-tubulin (TUB). In a dual culture assay, strain J4-3 significantly inhibited the mycelial growth of F. graminearum strain PH-1 and other fungal pathogens. In addition, wheat coleoptile tests showed that lesion symptoms caused by F. graminearum were significantly reduced in wheat seedlings treated with hyphal fragment suspensions of strain J4-3 compared to the controls. Under field conditions, applying spore suspensions and culture filtrates of strain J4-3 with conidial suspensions of F. graminearum on wheat spikes resulted in the significant biocontrol efficacy of FHB. In addition, wheat seedlings previously treated with spore suspensions of strain J4-3 before sowing successfully resulted in FHB reduction after the application of conidial suspensions of F. graminearum at anthesis. More importantly, wheat seedlings treated with hyphal fragments and spore suspensions of strain J4-3 showed significant increases in wheat growth compared to the controls under greenhouse and field conditions. Overall, these findings suggest that E. layuense J4-3 could be a promising biocontrol agent (BCA) against F. graminearum, causing FHB and a growth-promoting fungus in wheat. [ABSTRACT FROM AUTHOR]

The poor fracture toughness of La 2 Zr 2 O 7 hinders its practical application as a thermal barrier coating topcoat material. To toughen La 2 Zr 2 O 7 , metastable tetragonal 8 wt% yttria-stabilized zirconia ( t ’-8YSZ), has been introduced into the La 2 Zr 2 O 7 matrix by plasma spray quenching of 8YSZ powders and spark plasma sintering. An evident fracture toughness improvement has been achieved due to ferroelastic domains switching. The resulting toughness increase has a quadratic relationship with t ’ phase volume fraction below a critical value (30 vol%), beyond which it is far smaller to what expected owing to the residual stress being smaller than the ferroelastic coercive stress. [ABSTRACT FROM AUTHOR]

Solid-liquid equilibrium (SLE) of Na + //Cl − , NO 3 − , SO 4 2− -H 2 O quaternary system at 373.15 K was determined via isothermal solubility equilibrium method. The dry-salt phase diagram and the tri-prism stereogram of this system were obtained found on the solubility data. Without any solid solutions or double salts, the phase diagram is the simplest one of the quaternary system, consisting of one invariant point, three univariant curves, three crystallization fields of single salts, three cocrystallization fields for two salts and one cocrystallization field for three salts. At the same time, the physicochemical properties (density and conductivity) of this system were measured in the experiment. Moreover, comparing with the equilibrium phase diagrams in the temperature range from 258.15 K to 373.15 K, it could be found that the crystallization field of the double salt D (NaNO 3 .Na 2 SO 4 .10H 2 O) reduces with the temperature increases, and disappears at 373.15 K. With the growing temperature, the crystallization field of Na 2 SO 4 enlarges while the crystallization fields of NaNO 3 and NaCl both reduce. All above the experimental results obtained can be applied to solve the salt separation of the relative brine system mainly containing the four aforementioned ions as well as conduct further theoretical studies. [ABSTRACT FROM AUTHOR]

[Display omitted] • A heterostructure in CrCoNi alloy with nanograins dispersed around coarse-grains in size of a few micrometers is prepared. • It is fabricated by cold-rolling followed by sequential flash-annealing at increasing temperatures. • It is as strong as recovered nanostructure and at the same time as ductile/tough as homogeneous coarse-grains. • Hetero-zone interaction activates strain partitioning, mechanical twinning and long-range internal stress development, resulting in a multistage work hardening. • A strategy to retain ductility/toughness at ultrahigh strength: deploying dispersed heterostructrure and manipulating the grain size of soft zone. Here we advocate the strategic design of dispersed heterostructure to retain ductility and toughness in high-strength metals, using the equiatomic CrCoNi alloy as an example. Dispersed heterostructure, with nanograins and/or ultrafine grains (the hard zone) dispersed around micrometer-sized grain (the soft zone), is fabricated by cold-rolling followed by sequential flash-annealing at increasing temperatures. It displays a decent uniform elongation of ∼ 20 % and an exceptional strain energy density limit up to ∼ 240 mJ/mm3 at the strength level of ∼ 1.2 GPa, which is unattainable by its homogeneous as well as clustered heterogeneous counterparts. Grain size-dependent heterogeneous deformation evokes inter-zone interactions, which induce strain partitioning, activate additional mechanical twinning and promote developments of dislocation gradient and long-range internal stress near zone boundary sequentially, imparting a multistage work hardening with extraordinary strain hardening rate up-turn followed by slow attenuation. Dispersed heterostructure provides a higher density of zone boundary, ensuring more extensive inter-zone interaction and thus maximizing the extraordinary strain hardening to improve ductility. [ABSTRACT FROM AUTHOR]

The miscibility between two gels with largely different gelation behaviors is an interesting topic both scientifically and practically. This paper reports a novel bi-phasic system based on two natural polymers, hydroxypropyl methylcellulose (HPMC) which has a thermal gelation behavior, and hydroxypropyl starch (HPS) which has a cooling gelation property. While both biopolymers have the same glucose unit grafted with propylene oxide, and are compatible to a certain degree, they were observed immiscible because of their different gelation behaviors. The immiscibility of these two compatible polymers could result in special structures leading to different blend film properties. Regarding this, the morphology, thermal transition, mechanical properties and oxygen barrier property could be well tailored by the ratio of two biopolymers and the environmental conditions. The knowledge obtained from this work could be useful for understanding other similar systems with desirable structure and properties. [ABSTRACT FROM AUTHOR]

[Display omitted] Heterostructured metals possess superior mechanical properties exceeding the prediction by the rule-of-mixtures. However, it remains a challenge to understand the key microstructural factor that controls the extra work hardening. Here aided by a newly developed mechanism-based plasticity model that incorporates the constitutive law of the back stress induced by zone-scale deformation heterogeneity, we reveal that the hetero-zone boundary affected region (Hbar) plays the key role in controlling the synergistic mechanical responses of heterostructure. Specifically, the Hbar, characterized by high strain gradient with a constant characteristic width, is formed to coordinate inter-zone deformation heterogeneity. The extra work hardening originates primarily in the Hbar, where the accumulation of geometrically necessary dislocations develops back stress and forest hardening. Importantly, the extra work hardening increases proportionally with Hbar volume fraction, and the best strength-ductility combination is reached when Hbar approaches saturation. In addition, the influences of zone configuration, mechanical incompatibility, and zone volume fraction on Hbar effect are analyzed, which sheds light on potential strategies to enhance the Hbar effect for optimizing strength-ductility combination. [ABSTRACT FROM AUTHOR]

Accurate Q (quality factor) structures can provide important constraints for characterizing subsurface hydrocarbon/water resources in exploration geophysics and interpreting tectonic evolution of the Earth in earthquake seismology. Attenuation effects on seismic amplitudes and phases can be included in forward and inverse modellings by invoking a generalized standard linear solid rheology. Compared to traditional ray-based methods, full-waveform-based adjoint tomography approach, which is based on numerical solutions of the visco-elastodynamic wave equation, has the potential to provide more accurate Q models. However, applications of adjoint Q tomography are impeded by the computational complexity of Q sensitivity kernels and by strong velocity- Q trade-offs. In this study, following the adjoint-state method, we show that the Q (P- and S-wave quality factors QP and QS) sensitivity kernels can be constructed efficiently with adjoint memory strain variables. A novel central-frequency difference misfit function is designed to reduce the trade-off artefacts for adjoint Q tomography. Compared to traditional waveform-difference misfit function, this new central-frequency approach is less sensitive to velocity variations, and thus is expected to produce fewer trade-off uncertainties. The multiparameter Hessian-vector products are calculated to quantify the resolving abilities of different misfit functions. Comparative synthetic inversion examples are provided to verify the advantages of this strategy for adjoint QP and QS tomography. We end with a 3D viscoelastic inversion example designed to simulate a distributed acoustic sensing/vertical seismic profile survey for monitoring of CO2 sequestration. [ABSTRACT FROM AUTHOR]

Aflatoxins pose a major threat to food safety. These toxins are classified as hepatocarcinogens; however, their effect on the other tissues is unclear. During pregnancy, the fetus and placental tissues are especially sensitive to toxin exposure. In the present study aflatoxin B1 was found to induce the mRNA expression of corticotrophin-releasing hormone (CRH) in placental cells. A corresponding increase in CRH peptide in the culture medium was also observed. Since signal transduction pathways have been described previously in the control of CRH transcription, the status of protein kinase Cs (PKCs) and mitogen-activated protein kinases (MAPKs) were determined by Western analysis. In the aflatoxin B1-treated cultures, PKC α/βII/δ and ERK-1/2 were activated. As the PKC inhibitor bisindolylmaleimide I and the ERK inhibitor PD98059 could revert the induced CRH expression, the pathways dictated by PKC and ERK were likely involved in the transcriptional regulation. Electrophoretic mobility shift assay showed that C/EBP could be the ultimate activated transcription factor. Taken together, this study demonstrated that aflatoxin B1 could increase the parturition-related placental hormone in vitro . These findings might have significant implications for public health. [ABSTRACT FROM AUTHOR]

CdS quantum dots (QDs) have been successfully deposited on TiO 2 nanotube arrays (TNTAs) by successive ionic layer adsorption and reaction (SILAR) method for visible-light-driven hydrogen production and organic compound degradation. The composition, morphology and optical property have been characterized by the X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and UV–vis absorption spectra. The loading amount of CdS can be adjusted by controlling the deposition cycles which demonstrates correspondingly optical behaviors. CdS-TNTAs sample prepared by SILAR deposition with 15 cycles gives the highest hydrogen production rate of 1.89 μmol h −1 cm −2 for 15 mL solutions and the highest degrading rate. Moreover, a transfer mechanism of photo-generated electrons on CdS-TNTAs during the visible-light photocatalytic process is proposed based on the experimental analysis. Furthermore, the prepared sample has good stability and can be more easily reused than the powder catalyst. [ABSTRACT FROM AUTHOR]

A novel correction method was demonstrated for measuring spectral irradiance of light sources with a narrow bandwidth. Using the correction method based on differential quadrature method, an estimate of the true value was achieved with measured values of seven adjacent points. The formula of this correction method was derived. Numerical simulations and experimental validation of this correction method were also performed, respectively. This correction method could be used in radiometry, photometry, colorimetry, and other spectrometry fields, especially in the spectrum measurement of LED lamp. [ABSTRACT FROM AUTHOR]

A series of yttrium-doped lanthanum zirconate (La 1−x Y x ) 2 Zr 2 O 7 (0 ≤ x ≤ 1) bulk samples were prepared and their ionic conductivities were studied by impedance spectroscopy. It is found that intermixing of Y and La ions increases the conductivity of the end members pyrochlore-type La 2 Zr 2 O 7 and fluorite-type Y 2 Zr 2 O 7. Highest conductivity which is 2–3 orders of magnitude higher than that of La 2 Zr 2 O 7 and Y 2 Zr 2 O 7 is achieved in a two-phase sample which consists of both pyrochlore and fluorite phases. The enhanced conductivity in the two-phase sample is attributed to the presence of the pyrochlore-fluorite phase boundary, which has higher conductivity than the pyrochlore and the fluorite phase grains. The effect of the conductive phase boundary has been confirmed by a 2-dimensional finite element modelling. [ABSTRACT FROM AUTHOR]

• The NS surface layer supported by CG substrate displays significant strain delocalization and achieves improved uniform elongation. • The strain delocalization is realized by forming dispersed stable strain bands (SBs) and promoting the deformation of non-strain banding zone. • The intra-layer microstructure inhomogeneity and the limited strain hardening capability of intra-layer domains lead to SBs nucleation. • The inter-layer microstructure inhomogeneity causes extra inter-layer shear constraints, which stabilize SBs and promotes the deformation of non-strain banding zone. • The NS indeed becomes ductile, due to the extensive nanotwinning and dislocation activity enabled by strain delocalization. How to suppress strain localization in tensioned nanograined layer and make it ductile? This remains a great challenge. Here we explore the effects of microstructure inhomogeneity on the plastic behavior of nanostructured layer. A nanostructured CrMnFeCoNi high entropy alloy layer supported by coarse-grained substrate (in gradient architecture) is taken as an example. In the tensile deformation, strain examinations find that the nanostructure layer experiences significant strain delocalization by activating dispersed stable strain bands (SBs) and promoting the deformation of non-strain banding zone. Finite element analysis reveals that it is the intra-layer microstructure inhomogeneity which enables dispersed SBs nucleation from the mechanical weak sites. The inter-layer microstructure inhomogeneity introduces extra shear constraints from the coarse-grained substrate, which stabilizes SBs and improves the stress of non-strain banding zone, thereby suppressing the early catastrophic strain localization. Importantly, the strong nanostructure layer indeed becomes ductile (enables further work hardening) due to the activation of hierarchical nanotwinning and dislocation activity. [Display omitted] [ABSTRACT FROM AUTHOR]

Polymer-derived SiC fibers are critical structural and functional materials for high-temperature applications, whose service performance can be further improved by introduction of certain heterogeneous elements. Herein, flexible and thermal stable SiC fiber mats were prepared from boron-doped polyaluminocarbosilane (PACS) precursor by electro-spinning, curing and pyrolysis. Two boron-containing compounds o-carborane (oCB) and phenylboronic acid (PBA) were used as the boron sources and their effects on the properties and structure of the SiC fiber mats were investigated. The introduced oCB and PBA had obviously improved the ceramic yield of the cured fiber mats and the flexibility of the SiC fiber mats. However, PBA introduced more boron, but also more oxygen, which leaded to formation of more amorphous SiC x O y phases. Although only a small amount of boron was introduced by oCB, a more significant improvement in the thermal stability of the SiC fiber mat was obtained. This work provided a practical approach for fabrication of flexible and thermally stable SiC fiber mats. [ABSTRACT FROM AUTHOR]

Abstract: The effects and determining factors of substitutional defects on thermal conductivity (k) have been studied by introducing Hf4+ (96% heavier than, but a similar size to, Zr4+) and Ce4+ (21% larger and 50% heavier), to replace Zr4+ on the B site of La2Zr2O7 pyrochlores. La2(Zr1− x Ce x )2O7, exhibits a flatter k–T curve and a dramatically reduced high-temperature plateau k min. This is because the size rather than the mass difference between guest and host ions determines the flatness of k–T curves, whereas the absolute mass and size values of a dopant – particularly the latter – determine the plateau k min, as k min is proportional to the square root of the ratio of the elastic modulus E to the average atomic mass. Further, larger guest ion tends to effectively weaken a bond that shows ionic character and thus reduces E. The insights gained into the high-temperature plateau regime provide guidelines for the design and selection of a low-k material at high temperatures. [Copyright &y& Elsevier]

In order to realize laser frequency stabilization, the global evolution of an analyzer angle on the electrodeless-discharge-vapor-lamp-based excited-state Faraday anomalous dispersion optical filter (LESFADOF) with a single transmission peak operating on the Rb1529 nm (5P-4D) is presented. We find that the transmission of the line center peak at −80° arrives at 14% in a 3 cm length lamp contained natural Rb mixed with 2 torr Xe buffer gas operating at 250°C with 176 MHz radio frequency. When it is used to realize laser frequency stabilization, the LESFADOF at near −80° is appropriate. Whether a single transmission peak or double transmission peaks depend on the rf voltage when two polarizers are crossed. [ABSTRACT FROM AUTHOR]

In order to realize laser frequency stabilization, the global evolution of an analyzer angle on the electrodeless-discharge-vapor-lamp-based excited-state Faraday anomalous dispersion optical filter (LESFADOF) with a single transmission peak operating on the Rb1529 nm (5P 3/2-4D 5/2) is presented. We find that the transmission of the line center peak at −80° arrives at 14% in a 3 cm length lamp contained natural Rb mixed with 2 torr Xe buffer gas operating at 250°C with 176 MHz radio frequency. When it is used to realize laser frequency stabilization, the LESFADOF at near −80° is appropriate. Whether a single transmission peak or double transmission peaks depend on the rf voltage when two polarizers are crossed. [ABSTRACT FROM AUTHOR]

Active optical clock, a new conception of atomic clock, has been proposed recently. In this work, we propose a scheme of active optical clock based on four-level quantum system. The final accuracy and stability of two-level quantum system are limited by second-order Doppler shift of thermal atomic beam. To three-level quantum system, they are mainly limited by light shift of pumping laser field. These limitations can be avoided effectively by applying the scheme proposed here. Rubidium atom four-level quantum system, as a typical example, is discussed. The population inversion between 6 S and 5 P states can be built up at a time scale of 10 s. With the mechanism of active optical clock, in which the cavity mode linewidth is much wider than that of the laser gain profile, it can output a laser with quantum-limited linewidth narrower than 1 Hz in theory. An experimental configuration is designed to realize this active optical clock. [ABSTRACT FROM AUTHOR]

The intensity of fluorescence spectral lines of Rb atoms in the region of 350-1110 nm is measured in eletrodeless discharge lamp. The population ratio between the excited states is calculated according to the spontaneous transition probabilities with rate equations. At the same time, the population density of energy level is also obtained. The results provide the potential applications of electrodeless discharge lamp in atomic filter and optical frequency reference at higher excited states without a pumping laser. [ABSTRACT FROM AUTHOR]

Type-2 fuzzy set can control the uncertainty information more effectively than conventional type-1 fuzzy set because its membership function is three-dimensional. In this paper we perform the identification of disease-related genes based on DNA microarray by type-2 fuzzy set theory and established type-2 fuzzy membership function to describe the differences of the gene expression values generated form normal people's genes and patient's. We also make a comparison between our type-2 fuzzy method with the traditional fuzzy method. The results suggest the type-2 FM-d values are significantly different, which make the identifications more reasonable and convincing than the original one. [ABSTRACT FROM AUTHOR]

Abstract: The evolution of structure and thermal conductivity (k) has been studied for a range of Y–La2Zr2O7 solid solutions. Within the pyrochlore range (x <0.40) Y3+ solely substitutes for La3+ below a critical composition factor (x =0.15), above which it substitutes for both La3+ and the Zr4+. A glass-like k, approaching the amorphous limit, is observed within a certain composition range (0.20⩽ x <0.40). The glass-like k behaviour is attributed to a phonon localization effect that arises from small and weakly bound Y3+ cations (rattlers) oscillating locally and independently in oversized anionic cages [(La/Y)O8]. The ultralow and glassy k makes Y3+-doped La2Zr2O7 pyrochlores promising candidate materials for high temperature thermal barrier coating topcoats. [Copyright &y& Elsevier]

Resistance of carcinoma cells to anoikis, apoptosis that is normally induced by loss of cell-to-extracellular matrix adhesion, is thought to be essential for the ability of these cells to form primary tumors, invade adjacent tissues, and metastasize to distant organs. Current knowledge about the mechanisms by which cancer cells evade anoikis is far from complete. In an effort to understand these mechanisms, we found that ras, a major oncogene, down-regulates protease caspase-2 (which initiates certain steps of the cellular apoptotic program) in malignant human and rat intestinal epithelial cells. This down-regulation could be reversed by inhibition of a protein kinaseMek,a mediator ofRassignaling.Wealsofoundthat enforced down-regulation of caspase-2 in nonmalignant intestinal epithelial cells by RNA interference protected them from anoikis. Furthermore, the reversal of the effect of Rasoncaspase-2 achieved by the expression of exogenous caspase-2 in detached ras-transformed intestinal epithelial cells promoted well established apoptotic events, such as the release of the pro-apoptotic mitochondrial factors cytochrome c and HtrA2/Omi into the cytoplasm of these cells, significantly enhanced their anoikis susceptibility, and blocked their long term growth in the absence of adhesion to the extracellular matrix. Finally, the blockade of the effect of Ras on caspase-2 substantially suppressed growth oftumorsformedby the ras-transformed cells in mice. We conclude that ras-induced down-regulation of caspase-2 represents a novel mechanism by which oncogenic Ras protects malignant intestinal epithelial cells from anoikis, promotes their anchorage-independent growth, and allows them to form tumors in vivo. [ABSTRACT FROM AUTHOR]

SUMMARY Due to the influence of variations in landform, geophysical data acquisition is usually subsampled. Reconstruction of the seismic wavefield from subsampled data is an ill-posed inverse problem. Compressive sensing (CS) can be used to recover the original geophysical data from the subsampled data. In this paper, we consider the wavefield reconstruction problem as a CS and propose a piecewise random subsampling scheme based on the wavelet transform. The proposed sampling scheme overcomes the disadvantages of uncontrolled random sampling. In computation, an l1-norm constrained trust region method is developed to solve the CS problem. Numerical results demonstrate that the proposed sampling technique and the trust region approach are robust in solving the ill-posed CS problem and can greatly improve the quality of wavefield recovery. [ABSTRACT FROM AUTHOR]