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Exploring efficient, energy-saving and environmentally friendly phosphors is important for developing solid-state white light-emitting diodes (w-LEDs). Herein, we report a novel highly efficient green-emitting Ce3+-activated Ca2LuScAl2Si2O12 (abbreviated as CLSAS:Ce3+) garnet phosphor with high quantum efficiency and good thermal stability. These garnet phosphor samples doped with different Ce3+ ion concentrations were synthesized using a high-temperature solid-state method. The crystal structure and Ce3+ concentration-dependent luminescence properties of the phosphors were systematically studied. The as-prepared CLSAS:Ce3+ garnet phosphors exhibit broadband absorption in the spectral range of 250–510 nm with a maximum excitation wavelength of around 452 nm, matching well with the emission wavelengths of commercial blue LED chips. Under an excitation of 452 nm, the optimal CLSAS:4%Ce3+ sample exhibited a broad green emission band (emission peak: 531 nm; bandwidth: 114 nm) with CIE color coordinates of (0.3293, 0.5453) and high luminescence efficiency (internal quantum efficiency: 87.3%; external quantum efficiency: 56.6%). The CLSAS:4%Ce3+ sample also showed good thermal stability in the temperature range of 303–443 K. Its emission intensity at 423 K reached 79% of the emission intensity at 303 K, and it exhibited outstanding color stability with a small color chromaticity shift (ΔE = 1.07 × 10−3) at 423 K. Importantly, the fabricated w-LED device exhibits excellent photoelectric properties (CCT = 4978 K; Ra = 92.4; LE = 69.59 lm W−1). The obtained efficient CLSAS:Ce3+ green phosphors have the potential for application in high-quality w-LEDs. [ABSTRACT FROM AUTHOR]

Background: The COVID-19 pandemic has triggered a significant increase in academic research in the realm of social sciences. As such, there is an increasing need for the scientific community to adopt effective and efficient methods to examine the potential role and contribution of social sciences in the fight against COVID-19. Objectives: This study aims to identify the key topics and explore publishing trends in social science research pertaining to COVID-19 via automated literature analysis. Methods: The automated literature analysis employed utilizes keyword analysis and topic modelling technique, specifically Latent Dirichlet Allocation, to highlight the most relevant research terms, overarching research themes and research trends within the realm of social science research on COVID-19. Results: The focus of research and topics were derived from 9733 full-text academic papers. The bulk of social science research on COVID-19 centres on the following themes: 'Clinical Treatment', 'Epidemic Crisis', 'Mental Influence', 'Impact on Students', 'Lockdown Influence' and 'Impact on Children'. Conclusion: This study adds to our understanding of key topics in social science research on COVID-19. The automated literature analysis presented is particularly useful for librarians and information specialists keen to explore the role and contributions of social science topics in the context of pandemics. [ABSTRACT FROM AUTHOR]

The transmission accuracy of the ball screw depends on the processing quality of the thread profile. Traditional detection method of thread profile is complicated and inefficient. When shooting the thread profile of the ball screw in the normal section, the camera axis must be tilted to the lead angle, and adjustment errors are easily introduced from both the front view and the top view. When shooting in the axial section, the spiral lines block each other, so the actual thread profile cannot be captured for detection. In order to solve the above problems, a thread profile detection method is proposed: the theoretical equation of the ball screw thread profile in the axial section is derived based on the theoretical thread profile in the normal section, and the theoretical equation of the thread profile projection curve in the axial section is solved based on helix analysis, and the differential equation between them is obtained; then, the theoretical correction value of the thread profile projection curve is obtained by Linear Search to find the boundary value; the actual thread profile in both axial section and normal section is finally obtained with the theoretical correction value, which can support accurate measurement and detection of the key parameters of the thread profile. Experiments show that the proposed method can effectively improve the accuracy of the ball screw thread profile detection. [ABSTRACT FROM AUTHOR]

• A novel fatigue and creep-fatigue life prediction model is developed. • Model performance is fully validated by collected data from literatures. • The present model is superior to existing models. A high-precision and concise-form life prediction model is of essential significance to the deterministic life design and reliability assessment of high-temperature components in structural integrity field. In this work, a new model involving only one model parameter is developed to predict fatigue and creep-fatigue life under strain-controlled conditions, during which two physical parameters are extracted by intervening the data-driven symbolic regression results with domain knowledge. A dataset comprising 224 groups of high-temperature low-cycle fatigue and creep-fatigue interaction data for Inconel 718 alloy has been summarized from our prior works to facilitate model development. An additional 125 groups of Inconel 718 data with varying strain ratios and test temperatures are sourced from literature to highlight the advantages of the new model. Model comparisons are conducted with three physics-driven models and four data-driven models. It demonstrates that the new model exhibits superior comprehensive performance according to Bayesian information criterion in comparison to physics-driven models. Moreover, the new model achieves a better extrapolation of life prediction on unseen data set relative to data-driven models. Finally, the data sets of three different materials are collected to further evaluate the universality of the new model in this work. [ABSTRACT FROM AUTHOR]

• The work aims to provide theoretical bases for engineering damage level evaluation. • CF test is interrupted to study micro-evolution and mechanical property of GH4169. • Strength degradation is related to the coarsening and shearing of γ ″ precipitate. • Formation of voids and slip band leads to decrease in elongation after 50 % lifetime. • A mapping model from micro-evolution to macro-degradation is developed using KAM. Creep-fatigue interaction is identified as a primary failure mode for components operating under high temperatures. As operational durations extend, this interaction not only alters the material's microstructures but also initiates a gradual degradation in mechanical properties, significantly impacting its deformation and damage behaviors. In this work, the dynamic microstructural evolution of GH4169 superalloy during creep-fatigue was elucidated via qualitative characterization, and damage level evaluation method was subsequently developed by bridging microstructure degradation to mechanical property degradation. Creep-fatigue tests were performed at 650 °C with various tensile holding times and were interrupted at lifetime fractions of 10 %, 50 % and 80 % for further analysis and tensile evaluations. Results revealed that the prolonged exposure to holding times induced the coarsening of γ ″ precipitates alongside an increase in low-angle grain boundaries, culminating a reduction in creep-fatigue strength. The development of voids and cracks exacerbated the degradation of elongation, leading to a hybrid fracture mode encompassing both intergranular and transgranular cracking paths. Synthesizing microstructural evolutions to qualitatively categorize diverse degradation levels imparted a robust physical basis for damage evaluation. A mapping model was established to correlate the average kernel average misorientation (micro-degradation indicator) with the tensile plastic strain energy density (macro-degradation indicator). The damage level evaluation method was endowed with quantitative metrics utilizing this model, and its generality was additionally validated in P92 steel. This work offers an insight into the quantitative damage evaluations of creep-fatigue-induced degradations in materials, thereby providing a theoretical basis for the development of operation management and inspection plans of components. [ABSTRACT FROM AUTHOR]

Infectious diseases are illnesses caused by harmful pathogens from the exterior. Vaccines could prevent many people from disease infection. Over the past several years, the development and application of molecular diagnostic techniques have launched a revolution in monitoring infectious diseases. Polymerase chain reaction (PCR)-based systems to diagnose the etiologic agents of disease from clinical samples have been applicable in pathogen detection. We demonstrate a microfluidic chip for continuous flow PCR. The PDMS/glass bonding chip provides a miniaturized, cheap, and disposable material for pathogen diagnosis. The homemade thermal control module integrated with two cartridge heaters and one Peltier element supports the denaturation, extension, and annealing regions created inside the chip. Due to the large surface-to-volume ratio in the microchannel, the surface characteristics might augment the protein adsorption onto the channel surfaces and reduce the PCR amplification efficiency. We measure the hydrophilic properties, roughness of the wall and the structure of the surface under various surface treatments and express the PCR amplification efficiency. Results show that the most detailed is the PDMS sheet with the modification of Tween 20 of a concentration of 20% for the reduction of methyl peak of the absorption spectrum, the lowest contact angle, and the minor surface roughness. Next, the continuous flow PCR system amplifies a 385-bp segment of Q fever virus DNA to evaluate the performance of the DNA amplification. The overall product of Tween 20 is good because Tween 20 is an emulsifier, and it has excellent performance in both adhesion properties and coated samples. The need for point-of-care test (PoCT) devices has increased rapidly since the outbreak of COVID-19. The current portable device for PoCT will provide essential tools for real-time diagnosis. [ABSTRACT FROM AUTHOR]

Magmatic sulfide ores from the western and eastern intrusions of the world's third-largest Jinchuan Ni–Cu deposit are separated into disseminated, net-textured, and massive sulfides, or Fe-rich, transitional, Cu-rich ores. However, the composition of base metal sulfide (BMS) minerals from each intrusion and ore type still lacks investigation. By comparing the variations of chalcophile element composition of BMS minerals from different intrusions, sulfide textures, and ore types, new discriminant diagrams are constructed for subsequent exploration. BMS minerals from the eastern intrusion host more slightly chalcophile elements (Zn As, Sn Cd) because of the higher degree of crustal contamination, and less strongly chalcophile elements (Co, Bi, Se, Re, Ag, Te) due to the lower amount of prior sulfide segregation. R-factor modeling indicates that disseminated sulfides are formed at the highest R-factors, while massive sulfides are formed at the lowest. Correspondingly, R-factor upgrading results in higher concentrations of Se and Ag in BMS minerals from disseminated sulfides compared to net-textured sulfides. Most chalcophile elements in BMS minerals show positive or negative correlations with whole-rock Cu/Ni c ratios (Ni c represents corrected whole-rock Ni content after deducting Ni in olivine), suggesting extensive chalcophile element fractionation occurred during progressive sulfide fractionation. Furthermore, the elements that are slightly to moderately incompatible with monosulfide solid solution (MSS) while predominately hosted by BMS minerals (e.g., Cd, Se, Ag, and Te in chalcopyrite) show better correlations, making them preferable for tracing the sulfide fractionation. Utilizing the partial least squares-discriminant analysis models, we propose plots of Cd/(Co + As) vs. Bi/(Co + As), Ag vs. Bi/(Ag + Cd), and Co/(Ag + Cd) vs. Bi/(Ag + Cd) to discriminate chalcopyrite from different intrusions, sulfide textures, and ore types, respectively. Additionally, the occurrence of chalcopyrite with increased Bi/(Ag + Cd) and Co/(Ag + Cd) ratios and decreased Ag content presents promising clues for exploring Fe-rich massive sulfide ores. [Display omitted] • Variations of BMS compositions from different intrusions and types are clarified. • Compared the potential of each BMS as indicator minerals for exploration • Effective diagrams for discriminating various types of chalcopyrite are built. [ABSTRACT FROM AUTHOR]

Folding and other protein self-assembly processes are driven by favorable interactions between O, N, and C unified atoms of the polypeptide backbone and side chains. These processes are perturbed by solutes that interact with these atoms differently than water does. Amide NH···O=C hydrogen bonding and various p-system interactions have been better characterized structurally or by simulations than experimentally in water, and unfavorable interactions are relatively uncharacterized. To address this situation, we previously quantified interactions of alkyl ureas with amide and aromatic compounds, relative to interactions with water. Analysis yielded strengths of interaction of each alkylurea with unit areas of different hybridization states of unified O, N, and C atoms of amide and aromatic compounds. Here, by osmometry, we quantify interactions of 10 pairs of amides selected to complete this dataset. An analysis yields intrinsic strengths of six favorable and four unfavorable atom-atom interactions, expressed per unit area of each atom and relative to interactions with water. The most favorable interactions are sp²O-sp²C (lone pair-p, presumably n-p*), sp²C-sp²C (p-p and/or hydrophobic), sp²O-sp²N (hydrogen bonding) and sp3C-sp²C (CH-p and/or hydrophobic). Interactions of sp3C with itself (hydrophobic) and with sp²N are modestly favorable, while sp²N interactions with sp²N and with amide/aromatic sp²C are modestly unfavorable. Amide sp²O-sp²O interactions and sp²O-sp3C interactions are more unfavorable, indicating the preference of amide sp²O to interact with water. These intrinsic interaction strengths are used to predict interactions of amides with proteins and chemical effects of amides (including urea, N-ethylpyrrolidone [NEP], and polyvinylpyrrolidone [PVP]) on protein stability. [ABSTRACT FROM AUTHOR]

Eimeria necatrix is a high pathogenic pathogen second to Eimeria tenella causing chicken coccidiosis. However, the precise underlying molecular mechanisms of interaction between E. necatrix and chickens are not fully understood. Accumulating evidences suggest that micro-RNAs (miRNAs) play pivotal regulatory roles in various diseases, including parasitic diseases. In the present study, the expression profile of miRNAs in Hy-line variety white chicken small intestines infected with E. necatrix was studied by using deep sequencing. A total of 35 miRNAs (including 16 significantly upregulated and 19 significantly downregulated miRNAs) were significantly differentially expressed (DE) in infected tissues at 108 h postinfection (pi). Real-time polymerase chain of 10 miRNAs (including 5 upregulated and 5 down-regulated) randomly selected successfully confirmed the effectiveness of deep sequencing. Target prediction showed that 4,568 mRNAs could be regulated by 21 (including 12 upregulated and 9 downregulated) of 35 differentially expressed miRNAs. Functional analysis indicated that target genes of these differentially expressed miRNAs would be involved in pathways related to infection of E. necatrix, including cell differentiation, adhesion, proliferation, and apoptosis (e.g., MAPK signaling pathway and PPAR signaling pathway). To our best knowledge, this is the first study on the miRNA expression profile of small intestines during E. necatrix infection, and the findings in the present study suggested that these DE miRNAs would play important regulatory role in the interaction between E. necatrix and chicken intestines. [ABSTRACT FROM AUTHOR]

Background: Eimeria necatrix, the most highly pathogenic coccidian in chicken small intestines, can cause high morbidity and mortality in susceptible birds and devastating economic losses in poultry production, but the underlying molecular mechanisms in interaction between chicken and E. necatrix are not entirely revealed. Accumulating evidence shows that the long-non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) are key regulators in various infectious diseases. However, the expression profiles and roles of these two non-coding RNAs (ncRNAs) during E. necatrix infection are still unclear. Methods: The expression profiles of mRNAs, lncRNAs and circRNAs in mid-segments of chicken small intestines at 108 h post-infection (pi) with E. necatrix were analyzed by using the RNA-seq technique. Results: After strict filtering of raw data, we putatively identified 49,183 mRNAs, 818 lncRNAs and 4153 circRNAs. The obtained lncRNAs were classified into four types, including 228 (27.87%) intergenic, 67 (8.19%) intronic, 166 (20.29%) anti-sense and 357 (43.64%) sense-overlapping lncRNAs; of these, 571 were found to be novel. Five types were also predicted for putative circRNAs, including 180 exonic, 54 intronic, 113 antisense, 109 intergenic and 3697 sense-overlapping circRNAs. Eimeria necatrix infection significantly altered the expression of 1543 mRNAs (707 upregulated and 836 downregulated), 95 lncRNAs (49 upregulated and 46 downregulated) and 13 circRNAs (9 upregulated and 4 downregulated). Target predictions revealed that 38 aberrantly expressed lncRNAs would cis-regulate 73 mRNAs, and 1453 mRNAs could be trans-regulated by 87 differentially regulated lncRNAs. Additionally, 109 potential sponging miRNAs were also identified for 9 circRNAs. GO and KEGG enrichment analysis of target mRNAs for lncRNAs, and sponging miRNA targets and source genes for circRNAs identified associations of both lncRNAs and circRNAs with host immune defense and pathogenesis during E. necatrix infection. Conclusions: To the best of our knowledge, the present study provides the first genome-wide analysis of mRNAs, lncRNAs and circRNAs in chicken small intestines infected with E. necatrix. The obtained data will offer novel clues for exploring the interaction mechanisms between chickens and Eimeria spp. [ABSTRACT FROM AUTHOR]

Bi2Mg2/3Nb4/3O7 (BMN) pyrochlore thin films were deposited at 25 and 100 °C on Cu/Ti/Si substrates by pulsed laser deposition. Dielectric and leakage current properties of BMN films are investigated as a function of film thickness. The critical thicknesses showing the thickness dependence of dielectric constant are approximately 50 and 70 nm in BMN films deposited at 25 and 100 °C, respectively. The capacitances of interfacial layers in the films deposited at 25 and 100 °C are approximately 5.5 and 3.9 pF, respectively. The thickness dependence of leakage current characteristics was attributed to the copper diffusion into the BMN films. An intrinsic conduction of BMN films was controlled by Schottky emission and the barrier height was estimated as 0.9–1.2 eV in the temperature range from 25 to 100 °C. Film thickness in terms of leakage current characteristics is limited above 100 nm for embedded capacitor applications. [ABSTRACT FROM AUTHOR]

The paper focuses on the vacuum arc commutating characteristic which is a common basic problem in resistive fault current limiters. The current commutating characteristic of the current can be diverted into the current limiting resistor from the vacuum circuit breaker is mainly researched. The influence of the current amplitude, the current limiting resistor resistance, the arcing time, the transverse magnetic field and the current frequency on the time of the current commutation and the current in the moment of the completion transition is investigated and analyzed. According to the experimental results, the mathematical description of the vacuum arc commutating characteristic is obtained. The interaction between the vacuum arc and the transverse magnetic field is discussed. The paper provides the foundation for the structure and parameters optimization of the resistive fault current limiter. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Difficult bicyclic vinyl azides are achieved. • Intramolecular [4 + 2] cycloaddition is enabled by cationic rhodium catalyst. • No thermal conditions are required. • Vulnerable vinyl azide group survives. Abstract Although vinyl azide is an important class of functional group that possesses diverse reactivities and is a convenient synthon for N -heterocycles, cyclic vinyl azide remains underdeveloped due to difficult preparation. This work discloses a rhodium catalyzed intramolecular [4 + 2] cycloaddition reaction that can afford challenging fused bicyclic vinyl azides efficiently in ambient conditions and paves a facile route for the research in the chemistry of cyclic vinyl azides. [ABSTRACT FROM AUTHOR]

Concerns regarding the release of microplastics (MPs) into the environment led us to explore the relationship between the different environmental factors and physicochemical properties of MPs, as well as the change of interaction between MPs and organic pollutants. In this study, the effects of environmental factors (ageing conditions), such as pH, temperature, ionic strength, ageing time, and humic acid (HA) concentration, on the characteristics of MPs and their adsorption toward tetracycline (TC) were systematically investigated. The results showed that ageing factors such as pH, ionic strength, and temperature were found to have little impact on the adsorptive capacity of MPs for TC. However, MPs aged in HA solution exhibited a significant decreased adsorptive capacity for TC. HA, which has numerous functional groups, can cover the surface of MPs and change their hydrophobicity, thereby reducing the adsorption affinity to TC. The electrostatic repulsion between adsorbed HA and TC molecules may also decrease the adsorption of TC. In addition, the competing effect of HA for adsorption sites on the surface of MPs further reduces the adsorption of TC. The data presented in this work provide useful information for understanding the transfer of antibiotics by aged MPs, which is of fundamental importance to assess the environmental impact of MPs. [ABSTRACT FROM AUTHOR]

Background: Cryptosporidium baileyi is the most common Cryptosporidium species in birds. However, effective prevention measures and treatment for C. baileyi infection were still not available. Long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) play important roles in regulating occurrence and progression of many diseases and are identified as effective biomarkers for diagnosis and prognosis of several diseases. In the present study, the expression profiles of host mRNAs, lncRNAs and circRNAs associated with C. baileyi infection were investigated for the first time. Results: The tracheal tissues of experimental (C. baileyi infection) and control chickens were collected for deep RNA sequencing, and 545,479,934 clean reads were obtained. Of them, 1376 novel lncRNAs were identified, including 1161 long intergenic non-coding RNAs (lincRNAs) and 215 anti-sense lncRNAs. A total of 124 lncRNAs were found to be significantly differentially expressed between the experimental and control groups. Additionally, 14,698 mRNAs and 9085 circRNAs were identified, and significantly different expressions were observed for 1317 mRNAs and 104 circRNAs between two groups. Bioinformatic analyses of gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway for their targets and source genes suggested that these dysregulated genes may be involved in the interaction between the host and C. baileyi. Conclusions: The present study revealed the expression profiles of mRNAs, lncRNAs and circRNAs during C. baileyi infection for the first time, and sheds lights on the roles of lncRNAs and circRNAs underlying the pathogenesis of Cryptosporidium infection. [ABSTRACT FROM AUTHOR]

The purposes of the present work are to extend the previous energy-based model on the basis of strain energy density exhaustion and to estimate creep-fatigue endurance and accumulated damage using cycle-by-cycle concept in tension-hold-only tests. The nickel-based GH4169 superalloy at 650 °C is employed to fit material constants and to verify the prediction capacity of the present model under various loading conditions. The present model exhibits a higher accuracy than some existing models, especially for certain loading waveforms, where the half-life cycle cannot be considered as a representative one. In addition, the trajectory for time-dependent accumulated damage during the operating period can be monitored in the creep-fatigue interaction diagram. [ABSTRACT FROM AUTHOR]

The effect of volume fraction of δ phase, which was changed through changing the heat treatment conditions, on the strain-controlled fatigue behavior of Nickel-based GH4169 alloys at room temperature was investigated. The δ phase had almost no effect on fatigue life at strain amplitude higher than 0.5%. However, the fatigue life increased with increasing volume fraction of δ phase at the strain amplitude of 0.4%. The alloys with three different volume fractions of δ phase exhibited dual-slope Coffin-Manson relationships, which could be attributed to the changes in the deformation mode from twinning to slip bands as well as the crack initiation mode from transgranular to intergranular with increasing strain amplitude. [ABSTRACT FROM AUTHOR]

• Explore degradation of material mechanical properties in creep-fatigue process. • A damage variable D m is defined based on tensile plastic strain energy density. • Critical values of damage summation rules degrade as a power function of D m. • 3D damage diagram is constructed for evaluating creep-fatigue damage level. Progressive degradation of material mechanical properties in the low cycle fatigue (LCF) and creep-fatigue (CF) interaction at high temperature affects the safe operation of in-service materials. By considering material degradation, the present work aims to establish a method for evaluating LCF and CF damage levels with wide applicability. Material-level data accumulations as well as theoretical foundations of LCF and CF are presented, including interrupted LCF and CF tests, subsequent tensile tests and energy-based damage models. A damage variable representing the degradation of material mechanical properties is then defined based on the tensile plastic strain energy density (TPSED), the physical mechanism of which is reflected in the microstructure evolution and fracture appearance. By taking into consideration the material degradation threshold in the traditional damage summation rule, a new three-dimensional (3D) damage interaction diagram is established, where the additional third axis indicates the material degradation level. Finally, taking GH4169 alloy and P92 steel as examples, this work demonstrates the implemented procedures of damage level evaluation, which has been validated via the experimental data. [ABSTRACT FROM AUTHOR]

The failure of dual-phase alloys under tensile loading conditions is often due to the nucleation, growth and coalescence of voids at the interface between different phases from micromechanical point of view. The aim of this paper is to identify the failure mechanism and mode of dual-phase Ti-6Al-4V alloy in the form of plastic strain localization due to the incompatible deformation between the softer α phase and the harder β phase under the uniaxial tensile loading condition. The failure modes of as-received and heat-treated alloy are determined by tensile tests using sheet specimens. Then, a micromechanical modeling approach is developed on the basis of actual microstructure to predict the failure modes and ultimate ductility. Two different failure modes, i.e., shear band and vertical split band, can be found for as-received material. However, only vertical split failure is observed for heat-treated alloy. The predicted results agree well with the experimental observations. The microstructure-level inhomogeneity and incompatible deformation between the hard and soft phases are the main reason for failure. [ABSTRACT FROM AUTHOR]

The accumulated creep–fatigue damage is expected to be an important failure mechanism for lots of high-temperature components. The aim of this paper is to propose a modified strain energy density exhaustion model to predict the tension-hold-only creep–fatigue life. This model exhibits high accuracy due to the reasonable evaluation of creep damage. The proposed model elaborates the determinations of mean stress, stress relaxation rate and creep damage. A few existing experimental data sets of Grade 91 steel, Alloy 617 and 304 stainless steel are used to verify the prediction capacity of the present model under different temperatures and loading conditions. Results show that most of the experimental data falls into a range within a scatter band of ±1.5 on life. [ABSTRACT FROM AUTHOR]

This work provided an analytical model to solve the coupled mechanical-oxidation problem during the silicon thermal oxidation process. The silicon thermal oxidation behavior under two different mechanical load conditions, i.e., constant strain and uniaxial stress, were considered. The variations of oxide stress and scale thickness along with oxidation time were predicted. During modeling, all the effects of stress accumulation due to growth strain, stress relaxation due to viscous flow and the external load on the scale growth rate were taken into consideration. Results showed that the existence of external loads had an obvious influence on the oxide stress and scale thickness. Generally, tensile stress or strain accelerated the oxidant diffusion process. However, the reaction rate at the Si/SiO2 interface was retarded under uniaxial stress, which was not found in the case of constant strain load. [ABSTRACT FROM AUTHOR]

The mechanism of multi-scale fatigue crack propagation of Nickel-bases alloy GH4169 with different grain sizes was identified in this paper by using the specimens with micro-notches. Results showed that specimen with coarser grain exhibited longer fatigue life. Grain size effect on the growth rate of small crack cannot be distinguished due to the fluctuation of crack growth rate. The small fatigue crack stage accounted for a larger fraction of the total fatigue life for the specimen with finer grain size. An empirical formula was proposed to predict the relationship between the growth rate of small crack and crack length. [ABSTRACT FROM AUTHOR]

The mechanism of multi-scale fatigue crack propagation of Nickel-bases alloy GH4169 with different grain sizes was identified in this paper by using the specimens with micro-notches. Results showed that specimen with coarser grain exhibited longer fatigue life. Grain size effect on the growth rate of small crack cannot be distinguished due to the fluctuation of crack growth rate. The small fatigue crack stage accounted for a larger fraction of the total fatigue life for the specimen with finer grain size. An empirical formula was proposed to predict the relationship between the growth rate of small crack and crack length. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the anticancer activity of scopoletin against human prostate cancer. Methods: The anticancer activity of scopoletin was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MMT) assay. Flow cytometry using propidium iodide and annexin V-FITC was employed to study apoptosis and cell cycle analysis. Hoechst 33258 staining was used to assess the effect of scopoletin on cell morphology and apoptotic body formation in human prostate carcinoma (LNCaP) cells via Florescence microscopy and finally Western blotting was used to evaluate the effect of scopoletin on cyclin D1 and cyclin B1 expressions. Results: Scopoletin induced a dose-dependent growth inhibition in LNCaP prostate cancer cells. It induced G2/M phase growth arrest and led to an increase in the sub-G0/G1 cell population after treatment with increasing doses compared to control cells, scopoletin treatment resulted in cell shrinkage along with membrane blebbing which are characteristic features of cell apoptosis. Approximately 15.45, 32.6 and 21.71% of the cells underwent early apoptosis after treatment with 40, 80 and 100 μM of scopoletin respectively. Cyclin D expression diminished in a concentration-dependent manner when LNCaP cells were treated with different concentrations of scopoletin. Conclusion: These results reveal that scopoletin may be used as a natural chemotherapeutic agent against prostate cancer. [ABSTRACT FROM AUTHOR]

The aim of this paper was to develop a one-step in situ method to synthesize the TiN reinforced Al metallic matrix composite coatings on Ti6Al4V alloy. In this method, the Al powder and nitrogen gas were simultaneously fed into feeding nozzle during a laser nitriding process. The microstructure, microhardness and sliding wear resistance of TiN/Al coatings synthesized at different laser powers in laser nitriding were investigated. Results showed that the crack- and pore-free coatings can be made through the proposed method. However, the morphologies and distribution of TiN dendrites and wear resistance of coatings were strongly dependent on laser power used in nitriding. With increasing the laser power, the amount and density of massive TiN dendritic structure in the coating decreased and the elongated and narrow dendrites increased, leading to the increment of wear resistance of coating. When the laser power is high, the convectional flow pattern of the melt pool can be seen near the bottom of pool. [ABSTRACT FROM AUTHOR]

The effects of different factors on the creep–fatigue endurance of 316 stainless steel are reviewed in this paper. The factors include hold period, strain range, stress range at half-life and stress relaxation behavior. The strength and limitation of different creep–fatigue life prediction methods are also summarized from the available data. It is found that each method shows some agreement with prediction with a specific set of testing data. Standard deviations of different prediction methods are calculated to evaluate the prediction capacity of these methods. It is showed that ductility exhaustion model exhibits highest accuracy at two different temperatures. [ABSTRACT FROM AUTHOR]

Background Wnt/ß-catenin signaling pathway plays important roles in human cancer progression. Better understanding the mechanism underlying regulation of Wnt/ß-catenin signaling pathway might provide novel therapeutic targets for cancer treatment. Methods miR-610 expression levels in hepatocellular carcinoma (HCC) cell lines, HCC tissues and 76 archived HCC specimens were determined using real-time PCR. Cell viability was measured by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay. The level of DNA synthesis was determined by BrdU incorporation assay. Flow cytometry analysis was used to analyze cell cycle progression. The cells proliferation and tumorigenesis were determined by colony formation and anchorage-independent growth assays in vitro, and by xenograft tumors in vivo. Luciferase assay and micro-ribonucleoprotein complex immunoprecipitation assay were used to confirm the association of the targeted mRNAs with miR-610. Results miR-610 was downregulated in human HCC cells and tissues, and correlated with HCC progression and patient survival. Inhibition of miR-610 promoted, but overexpression of miR-610 reduced, HCC cell proliferation and tumorigenicity both in vitro and in vivo. Furthermore, we found that inhibiting miR-610 activated, but overexpressing miR-610 decreased, the Wnt/ß-catenin activity through directly suppressing lipoprotein receptorrelated protein 6 (LRP6) and transducin ß-like protein 1 (TBL1X). The in vitro analysis was consistent with the inverse correlation detected between miR-610 levels with expression of LRP6 and TBL1X in a cohort of human HCC samples. Conclusions Our results indicate that miR-610 downregulation plays essential roles in HCC progression and reduced miR-610 is correlated with Wnt/ß-catenin signaling pathway. [ABSTRACT FROM AUTHOR]

Obesity increases the incidence, progression and mortality of breast cancer among postmenopausal females. This is partly due to excessive estrogen production in the adipose tissue of obese females. Aromatase is a key enzyme in estrogen biosynthesis. In the current study, the tensional force-triggered inducibility of aromatase expression was observed to vary in ASCs isolated from different disease-free individuals. In addition, this phenomenon was associated with the activation of the aromatase PII promoter and its DNA methylation load. These findings highlight the impact of tensional forces on estrogen biosynthesis in obese females. [ABSTRACT FROM AUTHOR]

Context: Ceramide causes endothelial apoptosis and emphysema-like changes in animal models. Objectives: Test if plasma sphingomyelin, a major precursor of ceramide, would predict longitudinal increase in the percentage of emphysema-like lung on computed tomography (CT). Materials and methods: 3840 participants had their plasma sphingomyelin measured at baseline examination and their pulmonary emphysema measured on cardiac CT scans at baseline and on follow-up visits. Mixed effects models were used to adjust for potential confounders. Results: One standard deviation increase in sphingomyelin predicted a 0.12% per year (95% CI: 0.02-0.22; p = 0.019) greater increase of percent emphysema. Discussion and conclusion: Higher plasma levels of sphingomyelin predicted greater annual increase in quantitatively measured percent emphysema. [ABSTRACT FROM AUTHOR]

Background Vascular endothelial growth factor (VEGF)-D has been shown to promote lymph node metastasis in several cancers. Although generally overexpressed in ovarian carcinoma, its role in nodal dissemination of this cancer is unclear. To clarify the role of VEGF-D and the underlying molecular mechanisms, we investigated the function of VEGF-D using a mouse xenograft model of ovarian cancer. Methods Human ovarian serous adenocarcinoma SKOV3 cells were transfected with VEGF-D recombinant plasmid DNA, or with control vectors. The cells were injected subcutaneously into the footpads of nude mice. Tumor growth was evaluated weekly. Draining lymphatics were observed grossly with Evan's blue lymphangiography. Tumoral lymphatics were delineated with both Evan's blue and LYVE-1 immunostaining. Tumor metastases to lymph nodes were evaluated by H&E and CA125/CD40 staining. Expression of VEGF-D in primary tumors and levels of CA125 in involved lymph nodes were examined by immunohistochemistry. Tumor cell apoptosis was analyzed by Hoechst dyeing. Results Mice bearing VEGF-D overexpressing xenografts showed a significantly higher rate of lymph node metastasis and markedly greater tumor volume compared with the controls. The functional lymphatic vessels were denser and enlarged in marginal and central tumor portions. Additionally, higher CA125 expression was observed in the involved lymph nodes. Mice bearing VEGF-D overexpressing xenografts also exhibited a markedly lower apoptotic index compared with the controls. Conclusions Our data demonstrate the important role of VEGF-D in promoting lymph node metastasis by increasing tumor lymphangiogenesis, stimulating draining lymphatic vessel formation, and enhancing tumor invasiveness. Our findings show that VEGF-D can be a promising therapeutic target for ovarian cancer. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this paper was to address the fatigue behavior and mechanism of the laser cladded WC/Ni composite coatings under rolling contact condition. The coating was deposited by a 4kW continuous wave CO2 laser system. Rolling contact fatigue tests were conducted under lubrication condition at room temperature. The surface morphologies of the entire wear track for different rolling cycles were observed and recorded. Experimental results showed that the surface crack behaviors were strongly dependent on the location on the wear track. It was identified that spalling was the main fatigue failure mode of the coating under rolling cycles. The joining of surface cracks and the subsurface branched cracks led to the formation of the spall. The depth of the main subsurface crack was influenced by the distribution of the WC particles in the coating. [Copyright &y& Elsevier]

It has been demonstrated that nuclear factor-kappa B (NF-κB), which is overactivated in hepatocellular carcinoma (HCC), plays important roles in the development of HCC. Recently, a group of dysregulated micro RNAs were reported to be involved in HCC progression. Further understanding of micro RNA-mediated regulation of NF-κB pathway may provide novel therapeutic targets for HCC. In this study, we found that miR-451 expression was markedly downregulated in HCC cells and tissues compared with immortalized normal liver epithelial cells and adjacent non- cancerous tissues, respectively. Upregulation of miR-451 inhibited, while downregulation of miR-451 promoted, the tumorigenicity of HCC cells both in vitro and in vivo. These changes in the properties of HCC cells were associated with deregulation of two well-known cellular G1/S transitional regulators, cyclin D1 and c-Myc, which are downstream targets of NF-κB pathway. Furthermore, we demonstrated that miR-451 upregulation led to downregulation of cyclin D1 and c-Myc through inhibition of NF-κB pathway initiated by direct targeting of the IKBKB 3′-untranslated region. Therefore, these results suggest that miR-451 downregulation plays an important role in promoting proliferation of HCC cells and may provide the basis for the development of novel anti-HCC therapies. [ABSTRACT FROM PUBLISHER]

Background--Clock is a key transcription factor that positively controls circadian regulation. However, its role in plasma cholesterol homeostasis and atherosclerosis has not been studied. Methods and Results--We show for the first time that dominant-negative Clock mutant protein (ClockΔ19/Δ19) enhances plasma cholesterol and atherosclerosis in 3 different mouse models. Detailed analyses revealed that ClkΔ19/Δ19Apoe-/- mice display hypercholesterolemia resulting from the accumulation of apolipoprotein B48-containing cholesteryl ester-rich lipoproteins. Physiological studies showed that enhanced cholesterol absorption by the intestine contributes to hypercholesterolemia. Molecular studies indicated that the expression of Niemann Pick C1 Like 1, Acyl-CoA:Cholesterol acyltransferase 1, and microsomal triglyceride transfer protein in the intestines of ClkΔ19/Δ19Apoe-/- mice was high and that enterocytes assembled and secreted more chylomicrons. Furthermore, we identified macrophage dysfunction as another potential cause of increased atherosclerosis in ClkΔ19/Δ19Apoe-/- mice. Macrophages from ClkΔ19/Δ19Apoe-/- mice expressed higher levels of scavenger receptors and took up more modified lipoproteins compared with Apoe-/- mice, but they expressed low levels of ATP binding casette protein family A member 1 and were defective in cholesterol efflux. Molecular studies revealed that Clock regulates ATP binding casette protein family A member 1 expression in macrophages by modulating upstream transcription factor 2 expression. Conclusions--ClockΔ19/Δ19 protein enhances atherosclerosis by increasing intestinal cholesterol absorption, augmenting uptake of modified lipoproteins by macrophages, and reducing cholesterol efflux from macrophages. These studies establish that circadian Clock activity is crucial in maintaining low plasma cholesterol levels and in reducing atherogenesis in mice. [ABSTRACT FROM AUTHOR]

The oxidation of metallic materials at high temperatures is accompanied by atomic/ionic diffusion and stress. There exist stress effects on atomic/ionic diffusion and oxidation rate as well as diffusion-induced stress. In this work, we extend the models of diffusion-induced stress and reaction-induced stress to develop a coupled diffusion, reaction and mechanics model in the framework of linear elasticity by introducing a kinetic relationship between reaction rate and hydrostatic stress. This model demonstrates the effects of hydrostatic stress on chemical equilibrium constant and reaction rate, which are associated with reaction-induced stress. Using the diffusion-reaction-mechanics model, numerical analyses of three different cases are performed: a plate-like structure with fixed boundaries and constant concentration of solute atoms on surfaces, the growth of an oxide layer of a Cr–Fe alloy and the carburization of semi-infinite stainless steel. The numerical results reveal the presence of large compressive stresses and stress gradient in the oxide scale. Comparing the numerical results to experimental data available in literature, we illustrate the need of incorporating the interaction between stress and diffusion and the stress dependence of reaction rate in the growth analysis of the oxide layer and the carburized layer. It is expected that this model is applicable to other systems, such as lithium-ion and sodium-ion batteries. • A coupled chemo-mechanics model by introducing a relationship between oxidation and stresses is developed. • The numerical results reveal the presence of large compressive stress gradient in the oxide scale. • It is need to incorporate the interaction between stress and diffusion in the oxidation of metals. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this paper was to address the effect of WC content on the tensile properties of WC/Ni composite coatings deposited by laser cladding on 45# steel substrates. The tensile tests were performed in the chamber of a scanning electron microscope. Experimental results showed that the mechanical properties and fracture behavior of WC/Ni coatings were strongly dependent on the volume fraction of WC reinforcing particles in the coatings. The tensile properties of the coating decreased with increasing content of WC particle. When the WC content was relatively high, multiple through-width cracks (TWC) in the coating can be found. The number of through-width cracks in the coating as a function of applied strain was measured. From the in-situ observation of coating surfaces, most of cracks were initiated from the WC particle, and then propagated throughout the coatings. This phenomenon was attributed to the stress concentration in the WC particle or near the WC particle, which was confirmed by using finite element analysis. The present research may provide some insights on the development of designing methodology of composite coatings. [Copyright &y& Elsevier]

Abstract: Although sphingomyelin (SM) is the most abundant phospholipid in the plasma, next to phosphatidylcholine (PC), its physiological function in plasma is unclear. Here we employed plasma from various genetic models of mice which naturally differ in their plasma SM/PC ratios, to study the role of SM as a modulator of LCAT, the enzyme responsible for HDL maturation and the synthesis of cholesteryl esters (CE) in normal plasma. Serine palmitoyltransferase deficient mice, and SM synthase deficient mice, both of which have below normal SM/PC ratios, showed significantly elevated LCAT activities when assayed with the endogenous substrates. On the other hand, LDL receptor knockout mice, and apo E knockout mice, both of which have high SM/PC ratios, had markedly reduced (−80%) LCAT activities. The LCAT levels in plasma, as assayed with an exogenous substrate, were similar in all groups, except for a 45% decrease in apo E knockout mice. Plasma samples with high SM/PC ratios had lower percentage of 20:4, 22:5, and 22:6 CE all of which are formed by LCAT, and a higher percentage of the atherogenic 18:1 CE which is mainly derived from the action of liver ACAT, showing that in vivo, the contribution of LCAT to plasma CE is reduced while that of liver ACAT is increased. These results show that SM is a physiological modulator of LCAT activity as well as plasma CE composition, and this may contribute to the previously reported pro-atherogenic effect of high plasma SM levels. [Copyright &y& Elsevier]

It has been reported that phospholipid transfer protein (PLTP) is an independent risk factor for human coronary artery disease. In mouse models, it has been demonstrated that PLTP overexpression induces atherosclerosis, while its deficiency reduces it. PLTP is considered a promising target for pharmacological intervention to treat atherosclerosis. However, we must still answer a number of questions before its pharmaceutical potential can be fully explored. In this review, we summarized the recent progresses made in the PLTP research field and focused on its effect on apoB-containing- triglyceride-rich particle and HDL metabolism. [ABSTRACT FROM AUTHOR]

A unique tubular molecular-assembly, constructed by β-cyclodextrin and Na[Ni(mnt)2], was identified by X-ray crystallography. Inclusion complex Na[Ni(mnt)2]@β-cyclodextrin (1) crystallized in space group P21212 as hydrated head-to-head, tail-to-tail, and head-to-tail host pipelines with negatively charged [Ni(mnt)2]−guests included, exhibiting a 3 : 1 (host : guest) stoichiometry. The hydrophilic transition-metal coordination compound (Na[Ni(mnt)2]) was embedded within a hydrophobic cyclodextrin cavity, which resulted in a β-cyclodextrin trimer motif and one-third “empty” host packing model in the crystal. Induced circular dichroism (ICD) spectra of inclusion complex 1was investigated, which indicated the same penetration pattern of the guests in host cavities in solution phase as that discovered in the crystal structure. In addition, PM3 quantum chemistry calculations strongly supported the co-conformational alignments of inclusion complex 1that was identified in the crystal as well as in the solution. [ABSTRACT FROM AUTHOR]

Using a hydrothermal synthesis method, three novel silver complexes {Ag2(H2MDIP)(o-bix)2·H2O}n(1) (H4MDIP = methylenediisophthalic acid, o-bix = 1,2-bis (imidazol-1-ylmethyl)- benzene, {Ag8(MDIP)2(m-bix)}n(2) (m-bix = 1,3-bis(imidazol-1-ylmethyl)-benzene), {Ag4(MDIP)(p-bix)3·H2O}n(3) (p-bix = 1,4-bis(imidazol-1-ylmethyl)-benzene) were synthesized based on tetracarboxylic acid and auxiliary ligands containing N donors. Their structures have been characterized by X-ray crystallography. Complexes 1and 3have special 3D supramolecular networks constructed by hydrogen bonding, π–π stacking and electronic interactions to link the metal cations, anions and water molecules together. Complex 2exhibits a unique 2D architecture with unprecedented [Ag]7chains connected by strong Ag–Ag interactions. Thermal stabilities and luminescent properties of complexes 1–3were investigated. [ABSTRACT FROM AUTHOR]

The fruit of Chaenomeles speciosa is a traditional Chinese medicine used for the treatment of dyspepsia and various inflammatory diseases. In the present study, we evaluated the potential radical scavenging capacity, and activity against nitrous oxide, inflammatory cytokines production and neuramindase (NA) of its isolates. The results showed that 3,4-dihydroxybenzoic acid (1) displayed higher inhibitory activities on DPPH and NA with IC50 values of 1.02 μg/mL and 1.27 μg/mL respectively, and quercetin (2) also showed significant inhibitory action on DPPH and NA, with IC50 values of 3.82 μg/mL and 1.90 μg/mL. Compounds 1, 2 and methyl 3-hydroxybutanedioic ester (3) could inhibit the production of TNF- by 22.73%, 33.14% and 37.19% at 5 μg/mL (P < 0.05) compared with the control. In addition, compound 2 was found to be active on the release of IL-6 in RAW264.7 macrophage cells, with an inhibitory rate of 39.79% (P < 0.05). The anti-inflammatory effect of compound 3 is disclosed for the first time in this study. Avian influenza is usually accompanied by virus invasion followed by the occurrence of oxidative stress and serious inflammation, so the multiple effects of the isolates may play a cocktail-like role in the treatment of avian influenza, and C. speciosa components, especially quercetin, might be a potent source for anti-viral and anti-inflammatory agents. [ABSTRACT FROM AUTHOR]

A series of inclusion complexes between cyclodextrins (α-, β-, γ-cyclodextrin and HP-β-cyclodextrin, HP-β-cyclodextrin = 2-hydroxypropyl-β-cyclodextrin) and sodium maleonitriledithiolate (Na2mnt) were investigated by electronic spectra, induced circular dichroism (ICD) spectra, and quantum chemical studies. The inclusion complexes Na2mnt@α-cyclodextrin and Na2mnt@γ-cyclodextrin did not show any ICD signals, whereas Na2mnt@HP-β-cyclodextrin displayed two signs of splitting Cotton effects (CEs), with one positive CE couplet at 376 nm in the 365−410 nm region and the other negative at 277 nm in the 265−306 nm region. In addition, a dimeric host inclusion pattern of Na2mnt@HP-β-cyclodextrin in solution was determined by the method of continuous variation. Density functional theory (DFT) was used to assist assignment of the ICD signals in inclusion complexes Na2mnt@β-cyclodextrin and Na2mnt@HP-β-cyclodextrin in combination with the well-known Harata’s rule. The orientation of p → π* transition in Na2mnt chromophore was predicted by TD-DFT (time-dependent DFT) calculations to be along the CC double bond instead of being perpendicular. Upon titrations with Zn2늉溶⨧, reversals of the p → π* transition-relevant ICD peak and splitting CE were experimentally observed in the cases of Na2mnt@β-cyclodextrin and Na2mnt@HP-β-cyclodextrin, respectively, which strongly supported our hypotheses on their coconformations and the subsequent conformational changes of mnt chromophores occurring during the titration procedures. Therefore, on the basis of both the experimental data and TD-DFT calculations, the HP-β-cyclodextrin dimer host in inclusion complex Na2mnt@HP-β-cyclodextrin was disclosed, which in turn generated the exciton coupling between the two individually included guests and produced the splitting CEs as well as the reversals of CEs. [ABSTRACT FROM AUTHOR]

Many studies have suggested that VSMC (vascular smooth muscle cell) apoptosis plays a key role in destabilization and rupture of atherosclerotic plaques. Therefore protection for VSMCs from apoptosis is a promising approach to stabilize 'vulnerable' lesions. However, the mechanisms as to why VSMCs in the fibrous cap often appear as profilerated in early stages, but turn apoptotic in advanced stages, are still unknown. In the present study, using RNAi (RNA interference) technology and a CaN (calcineurin) antagonist, the correlation between CaN and RANTES (regulated upon activation, normal T-cell expressed and secreted) in cultured rat apoptotic VSMCs stimulated by IFNγ (interferon γ; 20 ng/ml) and CD40L (CD40 ligand; 100 ng/ml) was investigated. RANTES released from VSMCs in each group was measured by ELISA and its mRNA in VSMCs was determined by RT (reverse transcription)-PCR. The total activity and expression of CaN in VSMCs were detected by the zymochemistry method and Western blot analysis respectively. From the results of the present study it can be hypothesized that an elevated CaN concentration in endochylema, by the CD40-CD40L signal pathway, induces VSMC apoptosis accomplished by the overexpression of RANTES. Therefore RANTES is a potential target for treating vulnerable atherosclerotic plaques owing to its crucial downstream regulating role in CaN-dependent VSMC apoptosis. [ABSTRACT FROM AUTHOR]

Abstract: Background: Reconstruction of defects involving the knee and proximal one third of the lower leg presents a challenging problem in plastic surgery. Aim: To evaluate the reversed anterolateral thigh adipofascial flap for covering such defects. Methods: Between September 2006 and May 2007, one man and four women with defects around the knee and upper calf underwent reconstruction with reversed anterolateral thigh adipofascial flaps. The patients’ average age was 45 years (25–72 years). The size of the transferred flap ranged from 6cm×8cm to 12cm×13cm. Results: Four flaps with overlying skin grafts healed uneventfully; one skin graft showed minor necrosis due to haematoma, but the adipofascial flap survived well. Postoperatively the appearance of the reconstructive flap was acceptable. Conclusions: The reversed anterolateral thigh adipofascial flap is an effective option for covering defects of the knee and proximal calf. [Copyright &y& Elsevier]

Based on methylenediisophthalic acid (H4MDIP), three novel coordination polymers {[Mn2(MDIP)(bime)(H2O)2]2·2H2O}n (1) [bime = 1,2-ethanediylbis(imidazole)], {[Mn3(HMDIP)2(H2O)4]·4,4′-bipy·3H2O}n (2) [4,4′-bipy = 4,4′-bipyridine], and {[Co5(MDIP)2(H2O)6(μ-OH)2]·7H2O}n (3) have been synthesized and characterized by IR spectra, single-crystal X-ray diffraction analyses and thermal stability studies. The introduction of the bime and 4,4′-bipy ligands into Mn(CH3COO)2·4H2O and H4MDIP system leads to the formation of complexes 1 and 2, and the absence of the second ligand in the Co(NO3)2·6H2O and H4MDIP system leads to shape complex 3. Complex 1 is a 3D architecture with [Mn(–OCO–)]∞ helical chain. Coordination polymer 2 is a 2D sheet structure with trinuclear unit, in which two kinds of 21 helical chains ([Mn(IP)]∞ (IP = isophthalic acid) and [Mn(MDIP)]∞) are included. Complex 3 exhibits the 3D porous structure with a pentanuclear cobalt unit in which a 1D shallow helical chain of hydrogen-bonded water molecules is shaped. From the topology point of view, complex 1 exhibits a (4,6)-connected network with the Schläfli symbol (42.63.8)2(44.62.74.84.9), complex 2 displays a (3,6)-connected network with CdI2 topology, and complex 3 displays a (4, 8)-connected network with Schläfli symbol (44.62)2(416.612) which is a decorated scu net. [ABSTRACT FROM AUTHOR]

Abstract: Bi2Mg2/3Nb4/3O7 (BMN) pyrochlore films deposited on Cu/Si substrates at low temperatures are characterized for structural and dielectric properties as a function of oxygen flow rate. BMN films deposited at 150°C were partially crystallized with nano-sized crystallines of approximately 8.7nm. The dielectric properties of films are independent on variation of an oxygen flow rate, but the lowest leakage current densities observed in the range between 10 and 30sccm(standard cc/min). BMN films (50nm-thick) deposited at 100°C and an oxygen flow rate of 30sccm show a capacitance density of 570nF/cm2 and a breakdown voltage of 3V. [Copyright &y& Elsevier]

Acrylate elastomer (ACE) synthesized ourselves was mixed with antioxidative and UV stabilizer into polyoxymethylene (POM) matrices to investigate the effects of the ACE phase on the mechanical properties and UV stability of POM. For comparison, POM blended with same amount of TPU instead of ACE was used. Dispersion of the elastomer particles in POM matrices was investigated using SEM micrograph. Crystallinities of the specimen before and after UV ageing were also measured. The surface molecular weight and the mechanical properties of modified POM after UV ageing were determined. The result showed that excellent mechanical properties of the POM composites after UV-irradiation could be obtained by blending with ACE. [ABSTRACT FROM AUTHOR]

Summary: Cell proliferation and mRNA expression of insulin-like growth factor (IGF-I) and ‘mechanogrowth factor’ (MGF) were studied in osteoblasts in response to overload. Static and cyclic-stretching were used to apply superphysiological strains to cells. Overload was found to increase cell growth. IGF-I and its splicing variant, MGF, were measured using reverse transcriptase-polymerase chain reaction method and were found to be regulated differentially by mechanical signals at the mRNA level. Cyclic-stretching had a more significant effect on cell proliferation and mRNA expression levels of IGF-I and MGF, while unstrained cells did not express MGF at the mRNA level. These results demonstrated that gene expression is regulated by mechanical stimulation. MGF expression in osteoblasts in response to strain may be related to an autocrine mechanism. [Copyright &y& Elsevier]

Genetic deficiency of the plasma phospholipid transfer protein (PLTP) in mice unexpectedly causes a substantial impairment in liver secretion of apolipoprotein-B (apoB), the major protein of atherogenic lipoproteins. To explore the mechanism, we examined the three known pathways for hepatic apoB secretory control, namely endoplasmic reticulum (ER)/proteasome-associated degradation (ERAD), post-ER pre-secretory proteolysis (PERPP), and receptor-mediated degradation, also known as re-uptake. First, we found that ERAD and cell surface re-uptake were not active in PLTP-null hepatocytes. Moreover, ERto-Golgi blockade by brefeldin A, which enhances ERAD, equalized total apoB recovery from PLTP-nuH and wildtype cells, indicating that the relevant process occurs post-ER. Second, because PERPP can be stimulated by intracellular reactive oxygen species (ROS), we examined hepatic redox status. Although we found previously that PLTP-null mice exhibit elevated plasma concentrations of vitamin E, a lipid anti-oxidant, we now discovered that their livers contain significantly less vitamin E and significantly more lipid peroxides than do livers of wild-type mice. Third, to establish a causal connection, the addition of vitamin E or treatment with an inhibitor of intracellular iron-dependent peroxidation, desferrioxamine, abolished the elevation in cellular ROS as well as the defect in apoB secretion from PLTP-null hepatocytes. Overall, we conclude that PLTP deficiency decreases liver vitamin E content, increases hepatic oxidant tone, and substantially enhances ROS-dependent destruction of newly synthesized apoB via a post-ER process. These findings are likely to be broadly relevant to hepatic apoB secretory control in vivo. [ABSTRACT FROM AUTHOR]

Objective To study the role of extracellular signal-regulated kinase (ERK) in cerebral ischemia and the mechanism of protective effects of U0126 (1,4-diamino-2,3-dicyano-1,4-bis[2- aminophenylthio] butadiene) on ischemic brain. Methods `Mice underwent left middle cerebral artery occlusion (MCAO) by introducing a suture in the lumen. U0126 was injected intravenously through the internal jugular vein. The immuno-activity of phosphorylated ERK1/2 (pERKI/2), phosphorylated mitogen activated protein kinase kinase (pMEK), and phosphorylated Elk-1 (pElk-1) was assessed by Western blot analysis and immunohistochemistry. Interleukin (IL)-1β mRNA level was measured by ribonuclease protection assay. Results Phosphorylated ERK1/2 in 2 hours MCAO mice was down-regulated after intravenous injection of U0126. The inhibition was dose dependent and treatment time related. pMEK and pElk-l were also reduced in a similar fashion after U0126 treatment. IL-1β mRNA increased after 1 and 2 hours of MCAO. After injection of U0126, it was down-regulated during 1 to 4 hours after MCAO. Conclusion Intravenous administration of the MEK inhibitor UO126 inhibits pMEK, pERK1/2, and pElk-1 up-regulation induced by cerebral ischemia. The protective effect of UO!26 against ischemic injury is probably resulted from the reduction of IL-1β mRNA via the inhibition of ERK pathway. [ABSTRACT FROM AUTHOR]

The factors involved in the generation of larger high density lipoprotein (HDL) particles, HDL[sub 1] and HDL[sub c], are still not well understood. Administration of a specific synthetic liver X receptor (LXR) agonist, T0901317, in mice resulted in an increase of not only HDL cholesterol but also HDL particle size (Cao, G., Beyer, T. P., Yang, X. P., Schmidt, R. J., Zhang, Y., Bensch, W. R., Kauffman, R. F., Gao, H., Ryan, T. P., Liang, Y., Eaeho, P. I., and Jiang, X. C. (2002) J. Biol. Chem. 277, 39561-39565). We have investigated the roles that apoE and CETP may play in this process. We treated apoE-deficient, cholesterol ester transport protein (CETP) transgenic, and wild type mice with various doses of the LXR agonist and monitored their HDL levels. Fast protein liquid chromatography and apolipoprotein analysis revealed that in apoE knockout mouse plasma, there was neither induction of larger HDL formation nor increase of HDL cholesterol, suggesting that apoE is essential for the LXR agonist effects on HDL metabolism. In CETP transgenie mice, CETP expression completely abolished LXR agonist-mediated HDL enlargement and greatly attenuated HDL cholesterol levels. Analysis of HDL particles by electron microscope and nondenaturing gel electrophoresis revealed similar findings. In apoE-deficient mice, LXR agonist also produced a significant increase in very low density lipoprotein/flow density lipoprotein cholesterol and apolipoprotein B content. Our studies provide direct evidence that apoE and CETP are intimately involved in the accumulation of the enlarged HDL (HDL[sub 1] or HDL[sub c]) particles in mice. [ABSTRACT FROM AUTHOR]