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Background Live attenuated vaccines alter immune functions and are associated with beneficial outcomes. We previously demonstrated that live attenuated yellow fever virus (YFV) vaccine (LA-YF-Vax) dampens T-cell receptor (TCR) signaling in vitro via an RNA-based mechanism. We examined study participants before and after LA-YF-Vax to assess TCR-mediated functions in vivo. Methods Serum samples and peripheral blood mononuclear cells (PBMCs) were obtained before and after LA-YF-Vax (with or without additional vaccines) or quadrivalent influenza vaccine. TCR-mediated activation was determined by interleukin 2 release or phosphorylation of the lymphocyte-specific Src kinase. TCR-regulating phosphatase (protein tyrosine phosphatase receptor type E [PTPRE]) expression was also measured. Results Compared with prevaccination findings, LA-YF-Vax recipient PBMCs demonstrated transient reduction in interleukin 2 release after TCR stimulation and PTPRE levels, unlike in control participants who received quadrivalent influenza vaccine. YFV was detected in 8 of 14 participants after LA-YF-Vax. After incubation of healthy donor PBMCs in serum-derived extracellular vesicles prepared from LA-YF-Vax recipients, TCR signaling and PTPRE levels were reduced after vaccination, even in participants without detectable YFV RNA. Conclusions LA-YF-Vax reduces TCR functions and PTPRE levels after vaccination. Extracellular vesicles from serum recapitulated this effect in healthy cells. This likely contributes to the reduced immunogenicity for heterologous vaccines after LA-YF-Vax administration. Identification of specific immune mechanisms related to vaccines should contribute to understanding of the "off-target," beneficial effects of live vaccines. [ABSTRACT FROM AUTHOR]

To elucidate the adaptive strategies of Glechoma longituba in response to different light-quality colored films, the growth, photosynthesis, chloroplast ultrastructure, and triterpene acid accumulation were analyzed. In this study, four colored films improved electron transport and maintained the function of PSII, and allocated more light energy absorbed for photochemical reactions, thus increasing the photosynthetic capacity and ultimately improving dry mass accumulation. Additionally, blue film (BF) and green film (GF) enhanced photosynthesis by increasing stomatal openness and chlorophyll contents and maintaining chloroplast structural integrity, thereby promoting dry mass and triterpene acid (TA) accumulation of G. longituba. Red film excessively increased starch grains, inhibited photosynthate output and consequently reduced the concentration and yield of ursolic acid (UA). Yellow film decreased stomatal openness and chlorophyll concentrations, which was not conducive to chloroplast development, and also decreased the concentration and yield of UA. In conclusion, the application of BF and GF may represent an effective cultivation practice that can be used to achieve the highest TA yields in plantings of G. longituba. [ABSTRACT FROM AUTHOR]

To compare the performance of T2∗ imaging and apparent diffusion coefficient (ADC) in differentiating normal placentas from those complicated by fetal growth restriction (FGR). This prospective study included 28 control and 30 FGR placentas. Gradient-echo magnetic resonance imaging (MRI) at 16 different echo times and diffusion-weighted imaging (b-value of 0 and 800 s/mm2) were performed on all pregnant women using a 3 T MRI system. Both T2∗ imaging Z-score and ADC were significantly lower in the FGR placentas (ADC, (1.69 ± 0.19) × 10−3 versus (1.42 ± 0.28) × 10−3 mm2/s, p< 0.001; T2∗ imaging Z-score, -0.004 ± 0.95 versus -2.441 ± 1.48, p< 0.001). The area under the curve for T2∗ imaging Z-score and ADC was 0.917 (95% confidence interval [CI] = 0.842–0.991) and 0.788 (95% CI = 0.655–0.887), respectively. The performance of T2∗ imaging in differentiating FGR placentas was significantly better than that of ADC (Z = 2.043, p= 0.041). Placental T2∗ imaging was found to be more reliable than ADC in differentiating between normal and FGR placentas. [ABSTRACT FROM AUTHOR]

The notion of asymmetrical Hydrogen Bond (O:H-O) Cooperativity and Polarizability (HBCP) has enabled exploration of the core physics behind irregularities of water and ice, particularly, the evolution of mass density, phase stability, energy exchange, and their transition velocity under perturbation. We humbly share the initiatives of the quasisolidity presented between Liquid and Ice, the supersolidity pertained to polarization by electrification or molecular undercoordination, and the H ↔ H and O: ⇔ :O repulsivity owing to the respective injection of excessive protons and lone pairs to the liquid by solvation. The O—O repulsivity forms the key that drives the O:H-O bond to cooperatively relax its segmental length, cohesive energy, vibration frequency, and specific heat upon perturbation, which establishes an efficient set of parameters to feature the bonding and electronic dynamics in the frequency–space–time domains. An interplay of the segmental specific heats defines the mass densities, phase boundaries, and the exotic quasisolid (QS) phase that exhibits negative thermal expansivity through H-O contracting less than the scale of O:H expansion upon cooling. However, the H-O bond undergoes cooling elongation in the Liquid and the Ice-I phase and remains silent in the XI phase. H-O bond absorbs energy by contraction and does it inverse at expansion. The O:H nonbond always relaxes more than the H-O bond does in contrasting direction. Mechanical compression symmetrizes the O:H-O segmental length associated with polarization, which disperses inwardly the QS phase boundary to lower the T m for melting but raise the temperature T N for ice nucleation and the T V for evaporation, resulting in the phenomena of ice regelation and instant-ice formation. Polarization, however, has the contrast effect to compression on the hydrogen bond relaxation and phase transition. The polarization converts the pristine water into the gel-like, hydrophobic, and viscoelastic supersolid which is less-dense and thermally more diffusive and stable, entitling surface premelting, superheating at T m , and supercooling at T N and T V. Polarization enhances the dielectrics of water and widens the bandgap of ice. The supersolidity ensures the 120 K superelasticity of ice microfibers and the 330 K stability of the electrified water bridge crossing the rims of infilled containers. The high elasticity of the softer O:H nonbond and the interface electrostatic repulsivity secure the slipperiness of ice and the superfluidity of water traveling in fine channels. The skin supersolidity and the O:H-O bond memorability uniquely foster the Mpemba effect — warm water cools more quickly. The H ↔ H or O: ⇔ :O repulsivity modifies the bonding network and solution properties through solvent H-O bond elongation, solute H-O bond contraction, and polarization. The HBCP premise has thus correlated the irregularity of water and ice to the O:H-O bonding and electronic dynamics under perturbation. Further extension of the HBCP to aqueous and molecular assemblies involved with electron lone pairs and coupling interactions could be even more fascinating and profoundly promising. [Display omitted] • O—O repulsive coupling interaction entitles the irregularity of water and ice. • O:H-O bond cooperativity and polarizability revolutionizes the parameter space. • Perturbations drive the quasisolidity, supersolidity, H ↔ H and O: ⇔ :O repulsivity. • Specific-heat disparity resolves water's density anomalies and phase boundaries. • The T m and T N /T V vary respectively with the H-O and the O:H binding energy. • (e; ± ;H 3 O + ;HO −) ⋅ 4H 2 O:6H 2 O hydration revises solution's network and properties. [ABSTRACT FROM AUTHOR]

Aim: To analyse the clinicopathological features and ultrasound findings of the diffuse sclerosing variant of papillary thyroid carcinoma (DSV-PTC) and compare differences between children/adolescents (CAs) and adults.Materials and Methods: Medical records and ultrasound images of 97 consecutive DSV-PTC patients were reviewed and comparison was made between CAs and adults.Results: The average age was 31.2 ± 12.4 years old and 16.5% patients were CAs. Unilateral lobe was involved in 40.2% patients and 69.1% combined with Hashimoto's thyroiditis. Up to 95.9% patients had lymph node metastasis (LNM). CAs had more contralateral central LNM (CCLNM) and contralateral lateral LNM (CLLNM) than adults (p=0.047, p=0.025). Lung metastasis was also more common in CAs (p=0.002). Involved lobes mostly appeared as diffuse heterogeneous echogenicity on ultrasonography with isoechogenicity as the most common predominant echo (48.4%). Diffuse microcalcifications were observed frequently with grade 2-3 accounting for 52.3%. Lesions involving the whole gland lobe (diffuse type) occurred in 63.9%. Blood flow was poor in 71.6% (with grade 0-1). Microcalcifications of both lobes and metastatic lymph nodes and lesions involving (diffuse type) were more common in CAs (p=0.038, 0.002; 0.011). Of 39 patients with unilateral lobe involvement, ultrasonic sensitivity for CCLNM and CLLNM was only 50% and 66.7% respectively.Conclusion: DSV-PTC has characteristic ultrasonographic findings. DSV-PTC of CAs may be more aggressive than that of adults. Ultrasonic sensitivity for LNM of contralateral compartments was not satisfactory and diagnostic methods with good efficacy are required. [ABSTRACT FROM AUTHOR]

In order to explore the adaptive strategies of tree peony yl1 mutant in response to photooxidative stress, the changes of biochemical parameters, chlorophyll fluorescence, and the modulated 820-nm reflection of yl1 mutant and wildtype plants were compared. We found the activities of superoxide dismutase and catalase, the contents of soluble protein, proline, superoxide radicals, hydrogen peroxide, malondialdehyde, and relative electrical conductivity were significantly higher than those of the wild type. The photochemical efficiency of PSII significantly decreased, while the proportion of heat dissipation of yl1 mutant increased greatly. The donor and acceptor side and electron transfer of PSII were greatly inhibited. Meanwhile, the performance of PSI and coordination of two photosystems decreased markedly in yl1 mutant. The yl1 mutant could reduce the damage caused by photooxidative stress by increasing the activity of antioxidant enzymes, the content of some osmoregulatory substances, and the proportion of heat dissipation. [ABSTRACT FROM AUTHOR]

A sequential of concepts developed in the last decade has enabled a resolution to multiple anomalies of water ice and its low-dimensionality, particularly. Developed concepts include the coupled hydrogen bond (O:H–O) oscillator pair, segmental specific heat, three-body coupling potentials, quasisolidity, and supersolidity. Resolved anomalies include ice buoyancy, ice slipperiness, water skin toughness, supercooling and superheating at the nanoscale, etc. Evidence shows consistently that molecular undercoordination shortens the H–O bond and stiffens its phonon while undercoordination does the O:H nonbond contrastingly associated with strong lone pair ":" polarization, which endows the low-dimensional water ice with supersolidity. The supersolid phase is hydrophobic, less dense, viscoelastic, thermally more diffusive, and stable, having longer electron and phonon lifetime. The equal number of lone pairs and protons reserves the configuration and orientation of the coupled O:H–O bonds and restricts molecular rotation and proton hopping, which entitles water the simplest, ordered, tetrahedrally-coordinated, fluctuating molecular crystal covered with a supersolid skin. The O:H–O segmental cooperativity and specific-heat disparity form the soul dictate the extraordinary adaptivity, reactivity, recoverability, and sensitivity of water ice when subjecting to physical perturbation. It is recommended that the premise of "hydrogen bonding and electronic dynamics" would deepen the insight into the core physics and chemistry of water ice. [ABSTRACT FROM AUTHOR]

A sequential of concepts developed in the last decade has enabled a resolution to multiple anomalies of water ice and its low-dimensionality, particularly. Developed concepts include the coupled hydrogen bond (O:H–O) oscillator pair, segmental specific heat, three-body coupling potentials, quasisolidity, and supersolidity. Resolved anomalies include ice buoyancy, ice slipperiness, water skin toughness, supercooling and superheating at the nanoscale, etc. Evidence shows consistently that molecular undercoordination shortens the H–O bond and stiffens its phonon while undercoordination does the O:H nonbond contrastingly associated with strong lone pair ":" polarization, which endows the low-dimensional water ice with supersolidity. The supersolid phase is hydrophobic, less dense, viscoelastic, thermally more diffusive, and stable, having longer electron and phonon lifetime. The equal number of lone pairs and protons reserves the configuration and orientation of the coupled O:H–O bonds and restricts molecular rotation and proton hopping, which entitles water the simplest, ordered, tetrahedrally-coordinated, fluctuating molecular crystal covered with a supersolid skin. The O:H–O segmental cooperativity and specific-heat disparity form the soul dictate the extraordinary adaptivity, reactivity, recoverability, and sensitivity of water ice when subjecting to physical perturbation. It is recommended that the premise of "hydrogen bonding and electronic dynamics" would deepen the insight into the core physics and chemistry of water ice. [ABSTRACT FROM AUTHOR]

Due to the poor wettability of the AgCuTi alloy on the quartz fiber reinforced composite (QFSC), a reliable joining of the QFSC to itself or to other metals can be hardly achieved. In this study, vertically aligned carbon nanotube (VA-CNT) composed of multi-wall carbon nanotube (MWCNT) was synthesized on the QFSC surface by a plasma enhanced chemical vapor deposition method. As a result, the final contact angle decreased from 96.5° (without VA-CNT modification) down to 30.6° (with VA-CNT modification) at 870 °C with 10min holding duration. Besides, the reaction layers at the AgCuTi/QFSC interface transformed into continuous ones and the infiltration effects became more obvious after the VA-CNT modification. Finally, a possible mechanism how VA-CNT enhanced the wettability of the AgCuTi alloy on the QFSC surface was proposed. Defective sites on the MWCNT surface with a high chemical reactivity and the nanoscale capillary structure of the VA-CNT turned out to be the essential factors to promote the wetting process. This novel surface modification approach can offer new insights on addressing the wetting issues in composites preparation, brazing and soldering, etc.. Image 1098128 [ABSTRACT FROM AUTHOR]

The atomistic origin of the atomic vacancy or nanocavity induced hardening in hollow nanotubes and nanoporous structures has long been a puzzle. An analysis from the perspective of bond-order–length-strength correlation mechanism [C. Q. Sun, Prog. Solid State Chem. 35, 1 (2007)] has led to solutions that show that the shortened and strengthened bonds between the undercoordinated atoms in the negatively curved surface skins dominate the observed nanocavity strengthening and thermal instability of the porous structures. It is suggested that the broken bond derived local strain and quantum trapping and the associated energy densification provide pinning centers for inhibiting atomic dislocations and that the broken bond induced cohesive energy dropping dominate the thermal instability. On the other hand, nanocavities also provide sites that initiate the structure failure under plastic deformation. The agreement between predictions and the experimentally observed size dependence of mechanical strength of some nanoporous materials and the well-known phenomenon of hollow tube strengthening evidences for the proposed mechanism. [ABSTRACT FROM AUTHOR]

With the miniaturization of a solid device, quantum and interface effects become dominant not only in the static properties but also in the transport dynamics in the solid. Here we examine the dc conductance of a nanosolid by introducing the depression of the intra-atomic trapping potential in the surface skin [Sun, Phys. Rev. B 69, 045105 (2004)] as a perturbation to the conventional “quantum well” for tunneling electrons. It is derived that downshifts of the dc conductance peaks (that is, the incident energies for resonant tunneling) happens in an oscillatory way, depending on the strength of the perturbation. Besides, the downshifts of the peak positions due to the trapping potential well depression decrease as the size of the nanosolid is increased. [ABSTRACT FROM AUTHOR]

CF4 plasma-passivation enhanced size dependence of the blueshift in photoemission and photoabsorption, E2p-level shift, and band-gap expansion of porous silicon has been measured and analyzed numerically based on the recent “bond order-length-strength” correlation [ C. Q. Sun, Phys. Rev. B 69, 045105 (2004) ]. Matching predictions to the measurements conducted before and after fluorination reveals that fluorination further enhances both the crystal binding intensity that determines the band gap and core level shift and the electron-phonon coupling that contributes to the energies of photoemission and photoabsorption. This approach enables us to discriminate the effect of surface-bond contraction from the effect of surface-bond nature alteration on the unusual behavior of photons, phonons, and electrons in nanosolid Si. [ABSTRACT FROM AUTHOR]

An approach improving diamond–metal adhesion has been developed based on modeling predictions and experimental verifications on the interfacial stresses modified by catalytic reaction. It is found that N-plasma irradiating onto Ti and tungsten-carbide substrates generates tensile surface stresses while C-plasma irradiation creates strongly compressive stress at the surfaces, both of which deteriorate the diamond–metal adhesion. It is also found that surface oxidation prevents diamond nucleation. Therefore, we applied a graded TiCN interlayer with carefully adjusting the ratio of C and N in the gas mixture to neutralize the interfacial stress and, hence, we have improved the diamond–metal adhesion substantially. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Tree peony is a famous ornamental plant in the world. However, little is known about the leaf color mutants in tree peony. The present study monitored the physiological and photosynthetic properties of a yellow leaf mutant (yl1) in tree peony. The results showed that the yl1 mutant had lower pigment contents, but increased chlorophyll (Chl) a/b and carotenoids to Chl ratio. Microstructure and ultrastructure analysis showed that the yl1 mutant had smaller chloroplasts, few thylakoid stacks, and a few stroma thylakoid membranes remained along with clusters of osmiophilic granules, which might result from inhibition at the reactions from coproporphyrinogen III to protoporphyrin IX. The yl1 mutant had lower leaf net photosynthetic rate, stomatal conductance, transpiration rate, and stomata limitation value, but higher intercellular CO2 concentration. Analysis of simple sequence repeat markers indicated that four pairs of primers could obtain different bands in the genome of the yl1 mutant compared to the wild type. [ABSTRACT FROM AUTHOR]

Water dissolves salt into ions and then hydrates the ions to form an aqueous solution. Hydration of ions deforms the hydrogen bonding network and triggers the solution with what the pure water never shows such as conductivity, molecular diffusivity, thermal stability, surface stress, solubility, and viscosity, having enormous impact to many branches in biochemistry, chemistry, physics, and energy and environmental industry sectors. However, regulations for the solute-solute-solvent interactions are still open for exploration. From the perspective of the screened ionic polarization and O:H–O bond relaxation, this treatise features the recent progress and a perspective in understanding the hydration dynamics of Hofmeister ions in the typical YI, NaX, ZX 2 , and NaT salt solutions (Y = Li, Na, K, Rb, Cs; X = F, Cl, Br, I; Z = Mg, Ca, Ba, Sr; T = ClO 4 , NO 3 , HSO 4 , SCN). Phonon spectrometric analysis turned out the f (C) number fraction of bonds transition from the mode of deionized water to the hydrating. The linear f (C) ∝ C form features the invariant hydration volume of small cations that are fully-screened by their hydration H 2 O dipoles. The nonlinear f (C) ∝ 1 - exp.(- C/C 0) form describes that the number insufficiency of the ordered hydrating H 2 O dipoles partially screens the anions. Molecular anions show stronger yet shorter electric field of dipoles. The screened ionic polarization, inter-solute interaction, and O:H–O bond transition unify the solution conductivity, surface stress, viscosity, and critical energies for phase transition. Unlabelled Image • Ionic hydration stiffens the H–O and meanwhile softens the O:H phonon cooperatively. • Hydrating H 2 O dipoles full-screen a cation to keep its constant hydration volume. • Inter-solute repulsion limits an anionic hydration volume in a f(C)∝ 1-exp(-C/C 0) way. • Ionic negativity, polarity, radius, shape, and valence discriminate the ionic performance. • Inter-solute repulsion, and ionic polarization stem the properties of a solution. [ABSTRACT FROM AUTHOR]

We systematically examined the effect of (H, Li)Cl and LiOH solvation on the O:H O bond network deformation, surface tension (contact angle), solution electrical conductivity, thermomics, and viscosity evolution aiming to clarifying the functionalities for ions, lone pairs, and protons acting in these solutions. Results confirmed that H+ and electron lone pair ':' introduction turns out the (H 3 O+, OH−)·4H 2 O motifs and that the Li+ and Cl− form each a hydration volume through the screened electrostatic polarization. The (H 3 O+, OH−)·4H 2 O turns an O:H O bond into the H ↔ H anti–HB that disrupts the HCl solution network and its surface tension and into the O:⇔:O super–HB compressor that raises the LiOH solution surface tension and viscosity, as well as the solution temperature during solvation. The Li+/Cl− ion reserves/reduces its hydration volume because of the complete/incomplete screen shielding by the ordered hydrating H 2 O dipoles and the Cl− ↔ Cl− repulsion at higher concentrations. The invariant/variant Li+/Cl− hydration volume dictates, respectively, the linear/nonlinear concentration dependence of the Jones–Dole viscosity. Except for the HCl/H 2 O surface tension and LiOH/H 2 O viscosity, the conductivity, surface tension, and viscosity of these solutions follow the Jones–Dole notion that underscores the faction of bond transition from the mode of water to hydration. Proton H+, lone pair ':', Li+ and Cl− injection mediates cooperatively the HB network, conductivity, surface tension, and viscosity of (H, Li)Cl and LiOH solutions through H ↔ H fragilization, O:⇔:O compression, ionic screened polarization, Cl− ↔ Cl− repulsion, solvent H O bond elongation, and undercoordinated solute H O bond contraction. Unlabelled Image • Proton H+, lone pair ':', Li+ and Cl− hydration distort the (H, Li)Cl and LiOH solution network. • H ↔ H fragilization, O:⇔:O compression, ionic screened polarization, Cl− ↔ Cl− repulsion coexist. • Polarization and inter-solute repulsion determine the solution properties. • H O bond relaxation exchanges energy to the exo- and endothermic hydration. [ABSTRACT FROM AUTHOR]

Intermetallic alloy has become a hot topic in heterogeneous catalysis due to improved activity and stability. We report here the results of Pd monolayer supported on face-centered tetragonal ( fct ) Pd-M (M = Ni or Fe) intermetallic alloy as cathode materials by first principle calculations. Adsorbed O 2 is found to undergo hydrogenation process into OOH instead of direct dissociative mechanism. The oxygen reduction reaction (ORR) proceeds via four-electron transfer pathway on both surfaces. The enhanced activities are ascribed to moderate adsorption strength for ORR intermediates due to compression strain and substrate electron transfer. The dissolution potential analysis indicates that both Pd/PdNi(111) and Pd/PdFe(111) are stable under operating condition. Gibbs free energy analysis and barrier calculations suggest that the proposed Pd monolayer structures are promising for cathode material. These results can be useful in designing intermetallic Pd-M alloy as ORR electrocatalysts. [ABSTRACT FROM AUTHOR]

Aqueous charge injection in forms of electrons, protons, lone pairs, ions, and molecular dipoles by solvation is ubiquitously important to our health and life. Pursuing fine-resolution detection and consistent insight into solvation dynamics and solute capabilities has become an increasingly active subject. This treatise shows that charge injection by solvation mediates the O:H-O bonding network and properties of a solution through O:H formation, H↔H fragilization, O:⇔:O compression, electrostatic polarization, H2O dipolar shielding, solute-solute interaction, and undercoordinated H-O bond contraction. A combination of the hydrogen bond (O:H-O or HB with ':' being the electron lone pairs of oxygen) cooperativity notion and the differential phonon spectrometrics (DPS) has enabled quantitative information on the following: (i) the number fraction and phonon stiffness of HBs transiting from the mode of ordinary water to hydration; (ii) solute-solvent and solute-solute molecular nonbond interactions; and (iii) interdependence of skin stress, solution viscosity, molecular diffusivity, solvation thermodynamics, and critical pressures and temperatures for phase transitions. An examination of solvation dynamics has clarified the following: (i) the excessive protons create the H↔H or anti-HB point breaker to disrupt the acidic solution network and surface stress. (ii) The excessive lone pairs generate the O:⇔:O or super-HB point compressor to shorten the O:H nonbond but lengthen the H-O bond in H2O2 and basic solutions; yet, bond-order-deficiency shortens and stiffens the H-O bond due H2O2 and OH− solutes. (iii) Ions serve each as a charge center that aligns, clusters, stretches, and polarizes their neighboring HBs to form hydration shells. (iv) Solvation of alcohols, aldehydes, complex salts, carboxylic and formic acids, glycine, and sugars distorts the solute-solvent interface structures with the involvement of the anti-HB or the super-HB. Extending the knowledge and strategies to catalysis, solution-protein, drug-cell, liquid-solid, colloid-matrix interactions and molecular crystals would be even more fascinating and rewarding. [ABSTRACT FROM AUTHOR]

The resultant energy of solvent H–O bond exothermic elongation by O:⇔:O repulsion, featured at <3100 cm −1 , and the solute H–O bond endothermic contraction by bond-order-deficiency, at 3610 cm −1 , heats up the (Li, Na, K)OH solutions. The solution temperature increases linearly with the number fraction of the ordinary O:H–O bonds transiting into their hydration states. The elongated H–O bond emits >150% the O:H cohesive energy of 0.095 eV that caps the energy dissipating by molecular motion, thermal fluctuation, diffusion, and even evaporation. Therefore, the intramolecular H–O bond relaxation dictates the OH − solvation bonding thermodynamics and the performance of basic solutions. [ABSTRACT FROM AUTHOR]

We resolved the O:H-O bond transition from the mode of ordinary water to its hydration in terms of its phonon stiffness (vibration frequency shift Δω), order of fluctuation (line width), and number fraction (phonon abundance), fx(C) = Nhyd/Ntotal. The fx(C) follows fH(C) = 0, fLi(C) ∝ fOH(C) ∝ C, and fBr(C) ∝ 1 - exp(-C/C0) toward saturation with C being the solute concentration. The invariant dfx(C)/dC suggests that the solute forms a constantly sized hydration droplet without responding to interference of other ions because its hydrating H2O dipoles fully screen its electric field. However, the number inadequacy of the highly ordered hydration H2O dipoles partially screens the large Br-. The Br- then interacts repulsively with other Br- anions, which weakens its electric field and the fBr(C) approaches saturation at higher solute concentration. The consistency in the concentration trend of the fLiBr(C), the Jones-Dole viscosity η(C), and the surface stress of LiBr solution clarifies their common origin of ionic polarization. The resultant energy of the solvent H-O exothermic elongation by O: ⇔ :O repulsion and the solute H-O endothermic contraction by bond-order deficiency heats up the LiOH solution. An estimation of at least 0.15 eV (160% of the O:H cohesive energy of 0.1 eV) suggests that the H-O elongation is the main source heating up the solution, while the molecular motion, structure fluctuation, or even evaporation dissipates energy caped at 0.1 eV. [ABSTRACT FROM AUTHOR]

Silanized carbon fibers (CFs) and a high-density polyethylene with amino terminal groups (HDPE) were introduced into epoxy resins to fabricate high-performance composites. A. mechanical characterization of the composites was performed to investigate the effect of CFs in cured epoxy/HDPE systems. The composites revealed a noticeable improvement in the tensile strength, elongation at break, flexural strength, and impact strength in comparison with those of neat epoxy and cured epoxy/HDPE systems. SEM micrographs showed that the toughening effect could be explained by yield deformations, phase separation, and microcracking. [ABSTRACT FROM AUTHOR]

Correlation between the size-enhanced Stokes shift and the size-enlarged band gap expansion of porous silicon has been derived, which allows us to discriminate the effect of electron-phonon coupling from the effect of crystal binding on the blueshift in photoemission and photoabsorption of nanosolid silicon. Matching predictions to the measured peak shift of both photoemission and absorption and to the measured band gap expansion evidences the essentiality and validity of the recent bond order-length-strength correlation mechanism which suggests that the atomic coordination imperfection dictates the shape and size dependency of a nanosolid. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Based on the correlation between Raman shift and bond parameters, and further combined with experimental values of the Raman shift composition effect, the relationship between the composition and bond parameters of the 2D-M1−xM′xX2 and 2D-MX′2xX2(1−x) alloy materials was established. Numerical reproduction of the measurements clarified that the host atom phonons involved interaction with all of its z neighbors, whereas the doping atom phonon only involved interaction with a dimer. The doping of large atoms resulted in an elongation of the bond length, an increase in the equivalent coordination number, and enhancement of the binding energy. The doping of small atoms led to a contraction of the bond length, a decrease in the equivalent coordination number, and a weakening of binding energy. By quantifying the relationship between composition and bond parameters from Raman shifts, a deep understanding of two-dimensional alloy properties can be achieved. [ABSTRACT FROM AUTHOR]

Development of effective and green photocatalysts that are sensitive to visible light is highly crucial. The purpose of this investigation was to develop a new hydroxyapatite (HA) supported N-doped carbon quantum dots (N-CQDs) photocatalyst via a facile chemical strategy. The FTIR and TEM results confirmed that N-CQDs were successfully coupled with HA. The formed HA/N-CQDs composite exhibited a pronounced photocatalytic performance upon the degradation of methylene blue (MB) under visible-light irradiation. The degradation rate of MB by the composite was almost two times that of N-CQDs. The mechanisms for the improvement of the photocatalytic performance of the composites were discussed on the basis of the results. [ABSTRACT FROM AUTHOR]

We previously reported that LeMYB1 might be a crucial transcription factor in regulating shikonin formation in Lithospermum erythrorhizon. In this study, by overexpressing LeMYB1 under the control of CaMV35S promoter in L. erythrorhizon hairy roots, we further clarified the role of LeMYB1 in the shikonin formation and its regulation. The LeMYB1-overexpressing transgenic hairy roots were successfully induced by infecting seedling nodes with Agrobacterium rhizogenes strain ATCC15834 that carried the pBI121- LeMYB1 vector. The LeMYB1 transcripts were significantly up-regulated in the transgenic hairy root lines compared with the wild type lines, and the total content of shikonin and its derivatives was dramatically enhanced by the LeMYB1 overexpression. Real-time PCR results reveal that the enhanced shikonin biosynthesis in the overexpressing lines were mainly caused by a highly up-regulated expression of genes coding key enzymes ( PAL, HMGR, and PGT) and key regulators ( LeDI-2 and LePS-2) involved in the shikonin biosynthesis. Overall, our results suggest that LeMYB1 plays a positive role in regulating the shikonin biosynthesis in L. erythrorhizon. [ABSTRACT FROM AUTHOR]

Within the thermodynamic framework with internal variables by Rice (1971, "Inelastic Constitutive Relations for Solids: An Internal Variable Theory and Its Application to Metal Plasticity," J. Mech. Phys. Solids, 19(6), pp. 433-455), Yang et al. (2014, "Time-Independent Plasticity Related to Critical Point of Free Energy Function and Functional," ASME J. Eng. Mater. Technol., 136(2), p. 021001) established a model of time-independent plasticity of three states. In this model, equilibrium states are the states with vanishing thermodynamic forces conjugate to the internal variables, and correspond to critical points of the free energy or its complementary energy functions. Then, the conjugate forces play a role of yield functions and further lead to the consistency conditions. The model is further elaborated in this paper and extended to nonisothermal processes. It is shown that the incremental stress-strain relations are fully determined by the local curvature of the free energy or its complementary energy functions at the critical points, described by the Hessian matrices. It is further shown that the extended model can be well reformulated based on the intrinsic time in the sense of Valanis (1971, "A Theory of Viscoplasticity Without a Yield Surface, Part 1. General Theory," Arch. Mech., 23(4), pp. 517-533; 1975, "On the Foundations of the Endochronic Theory of Viscoplasticity," Arch. Mech., 27(5-6), pp. 857-868), by taking the intrinsic time as the accumulated length of the variation of the internal variables during inelastic processes. It is revealed within this framework that the stability condition of equilibrium directly leads to Drucker (1951, "A More Fundamental Approach to Stress-Strain Relations," First U.S. National Congress of Applied Mechanics, pp. 487-497) and Ilyushin (1961, "On a Postulate of Plasticity," J. Appl. Math. Mech., 25(2), pp. 746-750) inequalities, by introducing the consistency condition into the work of Hill and Rice (1973, "Elastic Potentials and the Structure of Inelastic Constitutive Laws," SIAM J. Appl. Math., 25(3), pp. 448-461). Generalized inequalities of Drucker (1951, "A More Fundamental Approach to Stress-Strain Relations," First U.S. National Congress of Applied Mechanics, pp. 487-497) and Ilyushin (1961, "On a Postulate of Plasticity," J. Appl. Math. Mech., 25(2), pp. 746-750) for nonisothermal processes are established straightforwardly based on the connection. [ABSTRACT FROM AUTHOR]

Analysis of volatile profiles from differently processed flaxseed oils (FSO) was performed by SPME-GC-MS, electronic nose (E-nose) and descriptive sensory analysis. A total of 61 volatiles were tentatively identified and then quantified. Among these components, 51 volatiles were obtained from the hot-pressed FSO, 47 from cold-pressed FSO, and 40 by solvent extraction. Principal component analysis (PCA) demonstrated that three FSO samples tested resulted in significant differences of three treatments ( p<0.05) and the marker compounds that contributed to discrimination of different processed FSO were hexanal, (E, E)-2, 4-pentadienal, (E, E)-2, 4-heptadienal, 6-hydroxy-2-hexanone, 1-hexanol, methyl-pyrazine, nonanal, 2,3-pentanedione, 1-butanol, acetic acid, hexanoic acid, and ethyl acetate. In addition, there was good consistency among GS-MS, sensory evaluation and E-nose analysis results. These results indicated that the process method has a significant effect on the aroma quality of FSO and may be helpful in evaluating aroma quality and the detection of frauds. Practical applications: The results showed that the major volatile components could be used as chemical markers to distinguish differently processed FSOs by the chemometric method. There was good consistency among GS-MS, sensory evaluation and E-nose analysis results, suggesting that E-nose technique combined with a PCA of the data provided by the sensor arrays has the good potential to evaluate FSO quality and the detection of frauds. Sixty-one volatiles were identified and significant differences were found in different processed flaxseed oils. Twelve major volatile compounds contributed to discrimination of different processed flaxseed oils. Flaxseed oil samples were distinguished from each other through PCA of E-nose data, suggesting that the E-nose can successfully discriminate different processed flaxseed oils. [ABSTRACT FROM AUTHOR]

Context. Water is usually the main component of ice mantles, which cover the cores of dust grains in cold portions of dense interstellar clouds. When molecular hydrogen is adsorbed onto an icy mantle through physisorption, a common assumption in gas-grain rateequation models is to use an adsorption energy for molecular hydrogen on a pure water substrate. However, at high density and low temperature, when H2 is efficiently adsorbed onto the mantle, its surface abundance can be strongly overestimated if this assumption is still used. Unfortunately, the more detailed microscopic Monte Carlo treatment cannot be used to study the abundance of H2 in ice mantles if a full gas-grain network is utilized. Aims. We present a numerical method adapted for rate-equation models that takes into account the possibility that an H2 molecule can, while diffusing on the surface, find itself bound to another hydrogen molecule, with a far weaker bond than the H2-water bond, which can lead to more efficient desorption. We label the ensuing desorption "encounter desorption". Methods. The method is implemented first in a simple system consisting only of hydrogen molecules at steady state between gas and dust using the rate-equation approach and comparing the results with the results of a microscopic Monte Carlo calculation. We then discuss the use of the rate-equation approach with encounter desorption embedded in a complete gas-grain chemical network. Results. For the simple system, the rate-equation model with encounter desorption reproduces the H2 granular coverage computed by the microscopic Monte Carlo model at 10 K for a gas density from 104 to 1012 cm-3, and yields up to a factor 4 difference above 1012 cm-3. The H2 granular coverage is also reproduced by a complete gas-grain network. We use the rate-equation approach to study the gas-grain chemistry of cold dense regions with and without the encounter desorption mechanism. We find that the grain surface and gas phase species can be sensitive to the H2 coverage, up to several orders of magnitude, depending on the species, the density, and the time considered. Conclusions. The method is especially useful for dense and cold environments, and for time-dependent physical conditions, such as occur in the collapse of dense cores and the formation of protoplanetary disks. It is not significantly CPU time consuming, so can be used for example with complex 3D chemical-hydrodynamical simulations. [ABSTRACT FROM AUTHOR]

The experiment was conducted to investigate the effects of dietary supplementation of fulvic acid on lipid metabolism of finishing pigs. One hundred eighty crossbred barrows (Landrace x Yorkshire, 60 ± 2.5 kg) were randomly allotted to 5 dietary treatments (36 pigs/treatment) and fed a basal diet supplemented with 0, 0.2%, 0.4%, 0.6%, and 0.8% fulvic acid for 42 d. Thirty pigs (6 pigs/treatment) were slaughtered at the end of the experiment. Blood samples and adipose tissue were collected for determination of blood parameters and lipid metabolic enzymes. The results showed that compared with the control group, dietary supplementation of 0.2%, 0.4%, and 0.6% fulvic acid significantly reduced mean backfat thickness of pigs (P < 0.05). The serum concentrations of low-density lipoprotein, leptin, growth hormone, insulin, and tri-iodothyronine were significantly increased by adding fulvic acid in diets (P < 0.05). With the raised concentration of dietary fulvic acid, hormone sensitive lipase (HSL) activity was significantly increased (P < 0.05), and lipoprotein lipase (LPL) activity was significantly decreased (P < 0.05) in adipose tissue. In conclusion, dietary supplementation of fulvic acid reduced the mean backfat thickness of pigs. This change related to the increased activity of HSL and the decreased activity of LPL in adipose tissue. [ABSTRACT FROM AUTHOR]

The prevalence of Clonorchis sinensis infection in freshwater fishes was surveyed in Heilongjiang Province, northeastern China, between August 2011 and September 2013. Thirteen species of freshwater fish (n = 3221) and one species of shrimp (n = 93) were collected from Songhua river, Nenjiang river and other lakes or ponds in 37 sites of 15 representative cities in Heilongjiang Province. They were individually examined by digestion technique, and the C. sinensis metacercariae were identified morphologically followed by confirmation using sequences of the second internal transcribed spacer of ribosomal DNA. Ten of the 13 examined species of freshwater fishes were infected with C. sinensis metacercariae, while all shrimps were negative. The overall prevalence of C. sinensis infection in 3221 examined freshwater fishes was 19.96%, with 42.57% (272/639) in Pseudorasbora parva, 22.55% (83/368) in Hemicculter leuciclus, 20.44% (121/592) in Carassius auratus, 17.71% (68/384) in Saurogobio dabryi, 10.85% (23/212) in Rhodeus ocellatus, 10.54% (48/455) in Phoxinus lagowskii, 8.20% (21/256) in Perccottus glehnii, 6.25% (5/80) in Misgurnus anguillicaudatus, 4.55% (1/22) in Xenocypris davidi, and 1.49% (1/67) in Cyprinus carpio. The average infection intensity in P. parva was 103.3 encysted metacercariae per gram of fish meat in Zhaoyuan city. The average prevalence of C. sinensis infection in Songhua river, Nenjiang river and lakes or ponds were 31.96% (503/1574), 11.30% (102/903) and 7.93% (59/744), respectively. The prevalence of C. sinensis infection in Zhaoyuan city (43.68%) was the highest among all sampling locations. These results revealed a high-prevalence of C. sinensis infection in freshwater fishes in Heilongjiang Province, northeastern China, posing significant public health concern. [ABSTRACT FROM AUTHOR]

Extensive mortality of susceptible spruce can be caused by spruce beetles at epidemic population levels, as in the ongoing outbreak in Southcentral Alaska. Although information on outbreak extent and severity underpins forest management and research, the data products available in Alaska have substantial gaps. Widely available high-resolution satellite imagery are a promising data source for detecting beetle kill because it is possible, though challenging, to identify individual trees. However, the applicability of automated deep-learning approaches for regional-scale mapping has not been evaluated. Here, we assess a deep convolutional network for mapping dead spruce in high-resolution (∼ 2 m) satellite imagery of Southcentral Alaska. The network identified dead spruce pixels across stand characteristics, achieving an average accuracy of 95%. To upscale to the stand scale, we mitigated overestimation of dead tree pixels at elevated severity by calibration. Stand-scale areal severity, the fraction of dead spruce pixels within a stand, was mapped with an RMSE of 0.02 at 90 m scale. The estimated severity exceeded 0.05 in fewer than 4% of the landscape, and approximately 90% of dead trees pixels were found in low-severity stands. Severity was weakly associated with stand-scale Landsat reflectance changes, a clear relation between SWIR reflectance change and severity only emerging above 0.1 severity. In conclusion, high-resolution satellite imagery are suited to automated mapping of beetle-associated kill at tree and stand scale across the severity spectrum. Such data products support forest and fire management and further understanding of the dynamics and consequences of beetle outbreaks. [Display omitted] • Automatic mapping of dead spruce trees in 2 m resolution satellite imagery. • Accurate stand-scale severity maps by calibrated upscaling. • Predominantly low to moderate severity, with most dead trees in low-severity stands. • Moderate-resolution images showed limited sensitivity to low-severity mortality. [ABSTRACT FROM AUTHOR]

A new dinuclear nitrido-bridged ruthenium complex with pyridine ligands ([PyH][RuN(Py)Cl] ( 1) is synthesized by reacting K[RuNCl(HO)2] ( 2) and excessive pyridine, then crystallized from dilute hydrochloric acid. Its crystal structure is determined by single crystal X-ray diffraction. The complex crystallizes in the form of red block crystals of the monoclinic symmetry and the space group C . The nitrido-bridged ruthenium complex has very short Ru-N distances. [ABSTRACT FROM AUTHOR]

Two iridium acetylacetonate complexes bearing axial bromide-substituted pyridine (3-bromopyridine, 1 and 4-bromopyridine, 2) are synthesized and their crystal structures are determined by single crystal X-ray diffraction. In both complexes, a distorted octahedral geometry of the central Ir(III) atom is formed by four oxygen atoms of two acetylacetone ligands, a carbon atom of one acetylacetone ligand, and a nitrogen atom of bromide-substituted pyridine. [ABSTRACT FROM AUTHOR]

The tree shrew ( Tupaia belangeri chinensis) is a squirrel-like lower primate or a close relative of primates, commonly used as an animal model in biomedical research. Despite more than three decades of usage in research, the clear relationships between body weight, fasting blood glucose concentration, sex and age among tree shrews remain unclear. Based on an investigation of 992 tree shrews (454 males and 538 females) aged between 4 months and 4 years old, we found that male tree shrews have significantly higher body weight and fasting blood glucose concentration than female tree shrews (p < 0.001). The concentration of fasting blood glucose slightly increased with body weight in males ( r = 0.152, p < 0.001). Meanwhile, in females, the body weight, concentration of fasting blood glucose and waist circumference positively increased with age (p < 0.001). Additionally, 17 tree shrews with Lee index [body weight (g)*0.33*1000/body length (cm)] above 290 had significantly higher body weight, waist circumference and glycated haemoglobin A1c ( Hb A1c) than non-obese tree shrews with a Lee index score below 290 (p < 0.001). Interestingly, 6 of 992 tree shrews (three males and three females, 2-4 years old) displayed impaired plasma triglycerides, Hb A1c, low-density lipoprotein and oral glucose tolerance test, suggestive of the early symptoms of metabolic syndrome. This study provides the first clear relationships between body weight, fasting blood glucose concentration, sex and age in tree shrews, further improving our understanding of this relationship in metabolic syndrome ( Met S). Given the similarity of tree shrews to humans and non-human primates, this finding supports their potential use as an animal model in the research of MetS. [ABSTRACT FROM AUTHOR]

Fractal dimension has been considered as a measure of fracture surface roughness of materials. Three-dimensional (3D) surface analysis is anticipated to provide a better evaluation of fracture surface toughness and fractal dimension. The objective of this study was to quantify the fracture surfaces and identify a potential relationship between fracture toughness and fractal dimension in a new type of core-shell titanium-iron particulate reinforced hydroxyapatite matrix composites using SEM stereoscopy coupled with a 3D surface analysis. The obtained results showed that both fracture surface roughness and fractal dimension increased with increasing amount of core-shell Ti-Fe reinforcing particles. The fractal dimension was observed to be a direct measure of fracture surface roughness. The fracture toughness of the composites increased linearly with the square root of fractal dimensional increment (i.e., followed the Mecholsky-Mackin equation well) due to the presence of Ti-Fe particles along with the effect of porosity in brittle materials. The 3D fractal analysis was suggested to be a proper tool for quantifying the fracture surfaces and linking the microstructural parameter to fracture toughness. [ABSTRACT FROM AUTHOR]

Ir(acac-O,O)(acac-C)(pyridine), 1 is synthesized, and its crystal structure is determined by single crystal X-ray diffraction. In the complex, the central Ir(III) atom displays a distorted octahedral geometry wherein the equatorial positions are occupied by four oxygen atoms of two acetylacetone ligands, and the apical positions are coordinated by a carbon atom of one acetylacetone ligand and a nitrogen atom of pyridine. [ABSTRACT FROM AUTHOR]

The ability to safely control transgene expression from viral vectors is a long-term goal in the gene therapy field. We have previously reported tight regulation of GFP expression in rat brain using a self-regulating tet-off rAAV vector. The immune responses against tet regulatory elements observed by other groups in nonhuman primates after intramuscular injection of tet-on encoding vectors raise concerns about the clinical value of tet-regulated vectors. However, previous studies have not examined immune responses following injection of AAV vectors into brain. Therefore, rat striatum was injected with tet-off rAAV harboring a therapeutic gene for Parkinson's disease, either hAADC or hGDNF. The expression of each gene was tightly controlled by the tet-off regulatory system. Using an ELISA developed with purified GST–tTA protein, no detectable immunogenicity against tTA was observed in sera of rats that received an intrastriatal injection of either vector. In contrast, sera from rats intradermally injected with an adenovirus containing either tTA or rtTA, as positive controls, had readily detectable antibodies. These observations suggest that tet-off rAAV vectors do not elicit an immune response when injected into rat brain and that these may offer safer vectors for Parkinson's disease than vectors with constitutive expression. [ABSTRACT FROM AUTHOR]

Abstract: Pure hydroxyapatite (HA) is brittle and it cannot be directly used for the load-bearing biomedical applications. The purpose of this investigation was to develop a new iron-containing HA/titanium composite via pressureless sintering at a relatively low temperature with particular emphasis on identifying the underlying toughening mechanisms. The addition of iron to HA/titanium composites led to a unique and favorable core/shell microstructure of Ti–Fe particles that consisted of outer titanium and inner iron, and good interfacial bonding with HA matrix. While the relative density, hardness and Young''s modulus reduced, the flexural strength, fracture toughness, fatigue resistance, and the related fracture surface roughness increased significantly with increasing amount of Ti–Fe particles. Different toughening mechanisms including crack bridging, branching and deflection were observed in the composites, thus effectively increasing the crack propagation resistance and resulting in a substantial improvement in the mechanical properties of the composites. [Copyright &y& Elsevier]

This investigation has studied the influence of the various casting variables on the quality of indirect squeeze castings primarily of aluminium alloys. The variables studied include gating design, filling velocity and squeezing pressure. The quality of the die casting was assessed by an analysis of both their surface condition and internal soundness. The cavity filling patterns with fanned gates and straight gate are compared. Straight gates are prone to cause jetting of the metal stream even at low velocities while fanned gates allow use of higher fill velocity without excessive jetting. A higher metal pressure provides a more complete fill of the die including improved compensation for solidification shrinkage. The gate velocity for cavity filling process is one of the most important factors for attaining a sound casting. Either too slow velocity or too rapid gate velocity can cause such defects as misrun, indications, jetting vortex, air entrapment, etc. Furthermore, the computer models using the UES ProCast software are conducted. [ABSTRACT FROM AUTHOR]

Soil particle size distribution (PSD) is an important physical attribute due to its great influence on soil properties related to water movement, productivity, and soil erosion. In this study we use classical and geostatistical methods to identify the changes and characteristics of PSD and selected chemical properties in soil at the 0-20 cm layer from different vegetation covers of ecological restoration along the agro-pastoral transition zone of northern China. The relationships between the fractal dimension of the PSD (Dm) and selected soil properties are discussed. The results show that: (1) with the accumulation of vegetation cover, sand content dropped from 867 to 180 g kg-1, and soil organic matter and nutrients increased significantly; (2) Dm ranged from 2.327 to 2.854. The higher the contents of clay, the higher the fractal dimension and the greater the vegetation; (3) significant linear regressions were found between Dm and soils properties such as sand, silt, clay, organic matter, total N, available N, P, K, cation exchange capacity and CaCO3. Therefore, the fractal model can be used as a main index to indicate the establishment of the restoration ecosystem and its degree of stabilisation. [ABSTRACT FROM AUTHOR]

Abstract: With the miniaturization of a solid, effects of surface strain and quantum trapping become increasingly important in determining its properties. As a result, low-dimensional materials manifest unusual features, especially in their energetic and mechanical behavior. The establishment of a consistent understanding on an atomic-level of the mechanism behind the fascinating behaviors of low-dimensional systems, which include monatomic chains, hollow tubes, liquid and solid surface skins, nanocavities, nanowires, and nanograins, as well as interfaces, has long been a great challenge. In this report, a literature survey is presented, followed by a theoretical analysis culminating in the development of a local bond average (LBA) approach that may complement existing approximations in terms of continuum medium and quantum computations. The LBA approach correlates the measurable quantities of a specimen to the identities of its representative bonds, and the energetic responses of these bonds (bond nature, order, length and strength) to external stimuli, such as changes in temperatures and coordination environments. It is shown that the shortened and strengthened bonds between under-coordinated atoms and the consequent local strain and quantum trapping dictate, intrinsically, the mechanical behavior of systems with a high proportion of such atoms. The thermally driven softening of a substance arises from bond expansion and lattice vibrations that weaken the bonds. The competition between the energy density gain and the residual atomic cohesive energy in the relaxed surface of skin depth determines, intrinsically, the mechanical performance of a mesoscopic specimen; the competition between the activation and inhibition of the motion of atomic dislocations motion dominates, extrinsically, the yield strength of the specimen during plastic deformation. Therefore, the mechanical behavior of a specimen depends on its shape, size, the nature of the bonds involved, surface and interface conditions, and the temperature at which the physical properties of the specimen is measured. Excellent agreement with existent measurements of temperature dependence of surface tension, size and temperature dependence of elasticity and extensibility, and the inverse Hall–Petch relationship in nanograins have been established. Furthermore, these agreements have led to quantitative information regarding the bond identities in monatomic chains and carbon nanotubes, as well as the factors dominating the sizes at which a grain is strongest. In addition, the interface electric repulsion between nanocontacts due to the skin trapping and the associated local charge densification may provide feasible mechanism for the superfluidity, superlubricity and superhydrophobicity as widely observed. The progress made insofar evidences the essentiality of the LBA approach from the perspective of bond formation, dissociation, relaxation and vibration and the associated energetics for the exposition of thermo-mechanical behavior of low-dimensional materials. Extending the application of the approach to junction interfaces, liquid surfaces, defects and impurities, chemically adsorbed systems, amorphous states, and substances under other applied stimuli such as pressure and electric field would contribute to better knowledge of such systems and could lead to the development of even more fascinating and profitable materials. [Copyright &y& Elsevier]

Eph receptors constitute the largest family of receptor tyrosine kinases in the human genome. EphA2 is one prominent member that is overexpressed and functionally altered in many invasive cancers, including pancreatic cancer. Dasatinib, which is a multi-targeted kinase inhibitor mainly developed for Bcr-Abl and Src family kinases, has recently been shown to have significant activity against EphA2. As selective small molecule EphA2 inhibitors are not currently available, we investigated the therapeutic potential to target EphA2 by dasatinib in pancreatic cancer cell lines. Using in vitro kinase assays, we found that EphA2 receptor tyrosine kinase was inhibited directly by dasatinib in a dose-dependent manner. Stimulation with ephrinA1 produced rapid increases of EphA2 phosphorylation that were inhibited by dasatinib, although the effects on activation of downstream signalling differed among the pancreatic cancer cell lines. Dasatinib also inhibited ligand-induced binding of EphA2 to the ubiquitin ligase Cbl, and the internalisation and degradation of EphA2, suggesting that these processes are dependent on kinase activity. Treatment with dasatinib decreased EphA2 phosphorylation in BxPC-3 xenografts, suggesting that dasatinib might have activity in pancreatic cancer due to EphA2 inhibition, besides its effects on Src. [ABSTRACT FROM AUTHOR]

Abstract: Filtration process is a typical tertiary treatment method for oily wastewater, suitable for the lower oil concentration and oil-in-water emulsion system. Therein the wettability of oil-in-water emulsions to filter media probably has some significant influences on the oil removal efficiency, namely a lipophilic filter medium have a better performance in oil droplets coalescence and attachment than a hydrophilic one. In this paper, a Lipophilic to Hydrophilic Ratio (LHR) concept was defined on the basis of Washburn''s equation and a test equipment was correspondingly designed, which were used to compare quantificationally the wettable selectivities of three filter media to oil and water. The selected filters were anthracite, manganese ore and quartz sand particles with a size fraction of +0.9 to 1.2mm and the wetting liquids were apolar cyclohexane and polar deionized water. At the same time, the effect of filter particle size on the LHR value was also explored. Linear least-square fits for all wetting rates gave regression coefficients of more than 0.9991, confirming the suitability of the experimental method for filter particles and further validating Washburn''s theory. The determined LHR values of anthracite, manganese ore and quartz sand are 1.93, 0.75 and 0.69, respectively, which means anthracite is lipophilic while manganese ore and quartz sand are hydrophilic. Moreover, for three selected particle size fractions the LHR values of anthracite particles are always the greatest and that of manganese ore are a little bit greater than quartz sand particles. Therefore, it can be deduced that the wettable differences probably be attributed to the differences of surface chemistries of filter samples. Namely, anthracite surface contains principally organic functional groups composed of carbon and oxygen elements and therefore presents apolar and lipophilic characterization, while manganese ore and quartz sand surfaces have SiO2 species and make them polar and hydrophilic. This conclusion is approximatively confirmed by the analysis results of X-ray photoelectron spectroscopy (XPS). [Copyright &y& Elsevier]

It has long been puzzling regarding the atomistic origin of the pressure-induced Raman optical phonon stiffening that generally follows a polynomial expression with coefficients needing physical indication. Here, we show that an extension of the bond−order−length−strength correlation mechanism and a local bond average approach to the pressure domain have led to an analytical solution to connect the pressure-induced Raman optical phonon stiffening directly to the bonding identities of the specimen and the response of the bonding identities to the applied stimulus. It is found that the pressure-induced blue-shift of Raman optical phonons arises from the bond compression and energy storage exerted by the compressive stress. Agreement between predictions and experimental measurements lead to the clarification of the detailed form for the polynomial coefficients, which provide an atomistic understanding of the physical mechanism of the external pressure induced energy gain, thermally induced bond expansion, as well as means of determining the mode atomic cohesive energy in a specimen. [ABSTRACT FROM AUTHOR]

Nonlinear absorption properties of a linear polymer (P1) in dimethylformamide (DMF) have been investigated using an open aperture Z-scan technique with 8 ns laser pulses at 532 nm. It was found that P1 shows saturable absorption (SA) at low intensities and a transition from SA to reverse saturable absorption (RSA) with an increase in intensities. The analysis is based on rate equations and indicates that the absorption transition in P1 arises from the fact that the absorption cross-section of the first excited-state σ12 is smaller than that of the ground-state σ01 and that of the second excited-state σ23, which is also the condition for the transition. [ABSTRACT FROM AUTHOR]

The optical limiting performance of lead nanowires in chloroform, ethanol and dimethylformamide was measured with 532-nm, 8-ns-duration laser pulses. Experiments showed that the optical limiting is strong and solvent dependent. The origins and the solvent effect of the optical limiting were analyzed. It is proposed that the absorption-induced scattering is the main role responsible for the optical limiting behavior and the solvent effect. [ABSTRACT FROM AUTHOR]

Electroacupuncture (EA) is widely used to treat disorders of the nervous system, such as stroke. The aim of the present study was to investigate the effect of EA on cerebral blood flow (CBF) in cerebral ischemic rats. We developed an animal model of cerebral ischemia (CI) by occluding the blood flow of both common carotid arteries in Sprague-Dawley (SD) rats; 2 or 15 Hz EA was applied to both Zusanli acupoints. The levels of nitric oxide (NO) in the peripheral blood and amounts of calcitonin gene-related peptide (CGRP) in the cerebral cortex and thalamus were measured. In addition, L-N (G)-nitro arginine methyl ester (L-NAME) was used to measure the changes in CBF induced by EA in rats with and without CI. The results indicated that both 2 and 15 Hz EA increase the mean CBF in rats with and without CI. However, neither 2 nor 15 Hz EA induced changes in levels of NO in peripheral blood or changes in CGRP levels in cerebral cortex and thalamus. In addition, L-NAME did not change the increase in CBF. We concluded that both 2 and 15 Hz EA at both Zusanli acupoints induced the increase of CBF in rats with and without CI. Whether the effect of EA is related to NO or CGRP will be investigated in a future study. [ABSTRACT FROM AUTHOR]

The tongue sole Cynoglossus semilaevis, an inshore fish in China, has showed great potential in aquaculture recently. However, poor survival was recorded during the period of weaning from live Artemia to artificial diets. In this paper, the influence of co-feeding larvae with live and inert diet on weaning performance was described. The C. semilaevis larvae were reared at 21 ± 1 °C and fed four different feeding regimes from 6 days post-hatching (dph): A, Artemia (10 individuals mL−1); B, Artemia (5 individuals mL−1); C, mixed diet (10 Artemia individuals mL−1 and 12 mg L−1 inert diet); and D, mixed diet (5 Artemia individuals mL−1 and 12 mg L−1 inert diet). Rotifers were also supplied in all cases during the first days of feeding. Mixed diets of commercial formulated feed and live prey (rotifers and Artemia) allowed larvae to complete metamorphosis, achieving similar specific growth rate (SGR) (18.5 ± 1.4% and 18.7 ± 1.6%) and survival (40 ± 7.6% and 48.5 ± 6.8%) compared with larvae fed on live feed alone (SGR of 18.3 ± 1.2%, 19.3 ± 1.9% and survival of 41.2 ± 11.3%, 38 ± 4.9%). However, in metamorphosed fish, when live feed was withdrawn on 31 dph, there was significant difference ( P < 0.05) in survival and growth among treatments. Metamorphosed fish, previously fed mixture diets during larval stages, had similar survival (62.1 ± 7.6% and 62.8 ± 3.9% for regimes C and D, respectively) but higher than that obtained for fish that previously fed on live feed (49.3 ± 2% and 42.1 ± 3.9% for regimes A and B, respectively) after weaning (day 60). The SGR of weaned fish previously fed live feed was similar (3.1 ± 0.6% and 2.92 ± 0.6% for regimes A and B, respectively) but lower than that recorded for fish that was fed from day 6 to day 30 on the mixed diet (4.5 ± 1.1% and 4.9 ± 0.3% for regimes C and D, respectively). It is suggested that weaning of C. semilaevis from early development would appear to be feasible and larval co-feeding improves growth and survival. [ABSTRACT FROM AUTHOR]

Abstract: Incorporating the recent bond order–length–strength correlation mechanism [C.Q. Sun, Phys. Rev. B 69 (2004) 045105] to the size dependence of Auger photoelectron coincidence spectra of Cu nanoparticles with and without being passivated has enabled us to gain quantitative information about the 2p and 3d level energies of an isolated Cu atom and their shift upon bulk formation. The developed approach also enabled us to discriminate the effect of crystal-field screening from the effect of valence recharging (due to surface passivation and substrate–particle interaction) on the binding energies to the electrons at different energy levels of a specimen. [Copyright &y& Elsevier]

Blood calcium concentration is maintained within a narrow range despite large variations in dietary input and body demand. The Transient Receptor Potential ion channel TRPV5 has been implicated in this process. We report here that TRPV5 is stimulated by the mammalian hormone klotho. Klotho, a β-glucuronidase, hydrolyzes extracellular sugar residues on TRPV5, entrapping the channel in the plasma membrane. This maintains durable calcium channel activity and membrane calcium permeability in kidney. Thus, klotho activates a cell surface channel by hydrolysis of its extracellular N-linked oligosaccharides. [ABSTRACT FROM AUTHOR]