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Smart and versatile salicylaldehyde Schiff's bases have been proved their excellent performances including large shocks shift, dual emission wavelengths and sensitive to environment for fluorescence analysis. Herein, a simple salicylaldehyde Schiff's base molecular (PBAS) with aggregation-induced emission (AIE) and the excited-state intramolecular proton-transfer (ESIPT) effects was constructed for detecting N2H4 and ClO−. The highly specific and sensitive response to N2H4 was witnessed by the fast turn-on of the strong blue fluorescence and to ClO− was observed by the rapid turn off of the weak green fluorescence simultaneous decomposing of the probe. The results of mass spectrum analysis showed that probe PBAS decomposed under the influence of N2H4, whereas probe PBAS can complex with ClO− and prevent effective ESIPT process. Benefiting from its high properties, this fluorescence molecular provides an effective tool for probing N2H4 and ClO− in live cells. [ABSTRACT FROM AUTHOR]

This study compared the nutritional quality and sensory attributes of wine made from dried Gouqi berries that were mature (NDG), mildly over‐matured (MDG) and severely over‐matured (SDG). Whilst these wines had the similar physicochemical properties, the MDG wine possessed higher polysaccharide levels, whereas the highest total flavonoids were found in the NDG wine. A slight difference in the amino acid composition was observed in these wines, whereas they exhibited the same biogenic amines composition. The MDG and SDG wines exhibited weaker fruity, floral and caramel aromas compared with the NDG wine. However, these wines showed similar chemical and fatty aromas. Sensory evaluation revealed that these wines could be distinguished by panelists, and the NDG wine was preferred by most tasters, followed by the MDG and SDG wines. These results suggest that the Gouqi wine made from mature berries exhibits the best nutritional and organoleptic quality. However, the over‐matured and severely over‐matured berries could also be useful for Gouqi berry wine production but with different nutritional and sensory properties. Copyright © 2017 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Mitochondrial research is important to the study of ageing, apoptosis, and metabolic diseases. Over the years, mitochondria have been studied with stimulation by chemical agents in a global manner for basic and applied research. This approach lacks of precision and accuracy in terms of spatial and temporal resolution. Here we demonstrate a direct and well-defined photostimulation targeting on single mitochondrial tubular structure using a tightly-focused femtosecond (fs) laser that could precisely activate mitochondria at single tubule level to show restorable fragmentation and subsequent recovery after tens of seconds. In these two processes, a series of mitochondrial reactive oxygen species (mROS) flashes was observed and found critical to the mitochondrial fragmentation. Meanwhile, transient openings of mitochondrial permeability transition pores (mPTP) were seen with oscillations of mitochondrial membrane potential. These activities were crucial for the recovery through scavenging the mROS. Without the feedback mechanisms, the fragmented mitochondria could not return back to their original tubular structure. These interesting observations show that photostimulation by fs laser is an active, precise, clean and well-defined approach to dissect the role of mitochondria in normal physiology and different kinds of diseases. [ABSTRACT FROM AUTHOR]

Wine mouthfeel plays an important role in sensory quality. Astringency, as an important aspect of mouthfeel, is composed of distinct sub-qualities associated with tannin-salivary colloidal interactions and loss of oral lubrication. Perception of wine mouthfeel is temporal – the sensory intensity of wine mouthfeel attributes changes over the oral process of evaluation. It remains unclear whether these changes in sensory are relevant to distinct physical processes. This study took sensory-instrumental and multivariate approaches to provide mechanistic insights into the wine mouthfeel during the temporal evaluation process. The sample set was created by doctoring ethanol, tannin, pH and mannoprotein in a Malbec. Wines were sensorily evaluated by a progressive profiling method and instrumentally tested using a soft-tribology protocol involving saliva. Results indicate that the scores of mouthfeel attributes are dependent on the interactive effect of matrix components. The decaying rate of the score for roughness after expectoration correlates with those for drying and pucker. The multivariate analyses indicate that tannin-protein interaction and high boundary friction in tribology are important in explaining the perception of all astringency sub-qualities. At the end of the evaluation, the boundary friction becomes less important in explaining the score of drying / roughness , while pH becomes less important in explaining the score of pucker. It is inferred that, after expectoration, saliva secretion recovers the oral lubrication; astringency sub-qualities are contributed less from the frictional mechanism but more from an alternative perceptive mechanism. The outcome could assist the wine industry in better managing the wine matrix to attain preferable mouthfeel characteristics. [Display omitted] • Matrix components interactively influence the temporal profiles of wine mouthfeel. • The intensity decaying rate of roughness correlates with those of drying and pucker. • Different astringency sub-qualities relate to distinct salivary friction responses. • Boundary friction in tribology is a requisite to perceive astringency sub-qualities. • Astringency sub-qualities may have multiple mechanisms during temporal perception. [ABSTRACT FROM AUTHOR]

Forsterite was synthesized by the molten salt method at 1 100 °C for 3 h, using analytically pure MgO and SiO2 as raw materials and analytically pure NaCI,Na2CO3,NaCI--Na2CO3 and Na2SO4 as the molten salt medium, respectively. The synthesized forsterite was analyzed by XRD,SEM,EDS and Jade. The results show that the purity of the forsterite synthesized with Na2CO3 or NaCI--Na2CO3 as the molten salt medium is very low, because Na2CO3 reacts with MgO and SiO2 to produce a large amount of Na2MgSiO4. The purity of the forsterite synthesized with NaCI as the molten salt medium is very high while that synthesized with Na2SO4 is high and a small amount of MgSiO3 is formed. The analysis shows that the mechanism of synthesizing forsterite in NaCI molten salt is "template growth", and that in Na2SO4 molten salt is "dissolution-precipitation". [ABSTRACT FROM AUTHOR]

The synchrotron radiation X-ray absorption fine structure (XAFS) technique is used to study the local structure of the key atom Ru in a series of Ni-Al-Ru ternary alloys with different Ru contents and heat treatments. All the investigated alloys consist of two phases, γ and γ', and especially Ru exists as an atom coordinated by 12 Ni atoms in the first shell without Ru clusters or intermetallic compounds. In γ phase Ru resides on the Ni lattice site introducing an outward relaxation of the neighboring atoms, while in the γ' phase Ru replaces the Al lattice site causing an inward relaxation. The interatomic distance of Ru–Ni bond and Debye-Waller factor are mainly affected by the composition and increase with the increasing Ru content. While the effect of heat treatment is obvious when the Ru content is higher than 6 at%. The variation of Ru local atomic structure can greatly influence the microstructural evaluation and deformation mechanism by changing the lattice misfit and the vacancy formation energy to control the creep properties of Ni-Ru-Al ternary alloys. [Display omitted] • The local atomic structure of Ru has been studied by synchrotron radiation XAFS. • Ru exists as an atom and no Ru clusters or intermetallic compounds are found. • The local atomic structure of Ru is mainly affected by the composition. [ABSTRACT FROM AUTHOR]

Wine mouthfeel and astringency play an important role in shaping the organoleptic quality and have been associated with tannin-salivary protein colloidal interactions. The mechanistic drivers of wine mouthfeel, especially those creating distinct astringency sub-qualities percepts, are yet to be fully realised due to the lack of appropriate measures. This study researched the friction behaviours of saliva-wine interactions, that allow inference of insights into the physicochemical origins of several important wine mouthfeel attributes. The red wine sample sets were created by doctoring various levels of ethanol, tannin, pH and mannoprotein on a Malbec. Samples were profiled sensorily and chemically. The friction behaviours of wine-saliva interaction and salivary viscoelasticity were investigated by soft-tribological protocols plus quartz crystal microbalance with dissipation. The sensory scores of mouthfeel attributes were modelled by physicochemical parameters using partial least squares regression. Results suggested that burning and resalivation are non-frictional-derived sensations driven by ethanol and acidity, respectively. Drying , grippy and rough are driven by tannin's adsorption on salivary film, which cause poor lubricity and a film strip-off thus exhibit as high boundary friction in tribology. Pucker is not directly driven by tannin but the weak viscoelasticity of salivary film, which is exhibited as the fast rate of friction increase in tribology. Smoothness is driven by less salivary protein precipitation, a highly viscoelastic salivary film, or the viscosity effects from mannoprotein. Fullness is driven by high viscosity by high ethanol. These models support the theory that wine mouthfeel attributes have dissimilar physicochemical origins that lead to distinct sensory experiences. [Display omitted] • Burning / resalivation are non-frictional percepts driven by high ethanol/acidity. • High tannin drives drying/rough/grippy as high saliva equilibrium boundary friction. • High ethanol/low pH drives pucker as a fast friction increase on salivary film. • Smoothness is driven by less saliva precipitation and high mannoprotein level. • Fullness is driven by high viscosity (high ethanol) and less saliva precipitation. [ABSTRACT FROM AUTHOR]

• Fatigue properties with composite waveform and variable amplitude of TC21 titanium alloy pulsed laser-arc hybrid welded joints were studied. • The micro-deformation mechanism and fatigue crack initiation mechanism of TC21 titanium alloy welded joints were revealed. • The predicted composite waveform and variable amplitude fatigue life of TC21 titanium alloy welded joints was within the triple error band. TC21 titanium alloy is widely used in the manufacturing of key components such as aerospace industry, its welded structure in actual service is often subjected to the cyclic loading with composite waveform and variable amplitude and leads to fatigue failure. Therefore, in this work, the composite waveform and variable amplitude fatigue properties of TC21 titanium alloy pulsed laser-arc hybrid welded joints were investigated in this paper, and the micro-deformation mechanism and crack initiation mechanism of welded joints under different initial maximum cyclic stresses were revealed. The results indicated that the micro-deformation mechanism was the competition between twinning and dislocation slip in the α′ phase at low stress. When the initial maximum cyclic stress increased, the generation and slip of dislocation dominated, and the main distribution of dislocations gradually transitioned from the α′ phase to the β phase. This caused the phase transition in the β phase to the α phase, which increased the energy at the α/β phase interface and reduced the resistance of fatigue microcrack initiation accordingly, thus promoting fatigue failure. In addition, pores were the main factor of fatigue failure for welded joints. Therefore, in this work, the influence of defect size, location and shape on the fatigue life of welded joints was considered to develop a fatigue life prediction model based on the control parameter Z-parameter and equivalent stress amplitude. The predicted composite waveform and variable amplitude fatigue life of TC21 titanium alloy welded joints was within the triple error band. [ABSTRACT FROM AUTHOR]

Astringency mouthfeel is an important indicator of wine sensory quality that has been associated with colloidal interactions between tannins and salivary proteins, and a depletion in the lubricating salivary film. However, astringency is a complex sensation that has several contributing sub-qualities that may each have different physicochemical origins. We find that the model wine sample set varying in tannin, pH and polysaccharide content exhibit variations in the main sub-qualities: drying , rough and pucker. A range of soft-tribological methods involving saliva are used to gain mechanistic insight into these sub-qualities. Results suggest that rough is a secondary sub-quality that can be elicited by either drying or pucker , while these two sensations are driven by high tannin and low pH, respectively. Samples with 'chemically-equalised' astringency, which have similar colloidal stability upon interaction with saliva (saliva precipitation index), are also found to have varying sub-qualities and tribological responses. The boundary friction of saliva-wine mixtures in Stribeck curve aligned with drying , and the rate of increase in boundary friction of a salivary pellicle upon contacting wine aligned with pucker. Rough is not found to scale with any physical measure we explored. Quartz crystal microbalance indicated that the tannin, rather than pH, interacts with the salivary protein film to cause an increase in surfaces adsorbed mass in the absence of significant shear. The results indicate that while tannin and acid both contribute to the perception of astringency, the mechanisms by which they do this have different origins that lead to differences in sub-qualities. Image 1 • Samples with chemically-equalised astringency exhibited different sub-qualities. • Rough is a secondary sub-quality elicited by either drying or pucker. • Higher tribology boundary friction associated with high tannin is linked to drying. • Lower pH linked to pucker and a faster collapse of salivary pellicle in tribology. • Higher tannin increased adsorbed mass on the salivary film in QCM-D. [ABSTRACT FROM AUTHOR]

Relaxation behaviors of highly rejuvenated Zr 50 Cu 40 Al 10 bulk metallic glass was investigated using synchrotron X-ray scattering coupled with differential scanning calorimetry. The relaxation of rejuvenated volume is found to correspond to a marked exothermic event prior to the glass transition. High-energy synchrotron X-ray measurements of the structure factor show that annihilation of rejuvenated volume correspond to a sharpening of the scattering peaks. The calculated reduced pair distribution function suggests that the atomic re-arrangement in the second shell are largely responsible for the reduction in the free volume and decrease in full-width at half-maximum of the Total Structure Factor observed during structural relaxation. Mechanical properties in the highly rejuvenated metallic glass were evaluated as a function of annealing temperature. • Relaxation process in the rejuvenated metallic glass was firstly studied using high energy X-ray scattering. • Atomic packing at second coordination shell plays an important role during relaxation of highly rejuvenated samples. • Crystallization in rejuvenated samples occurs earlier than it in as-cast one. • Elastic modulus and hardness linearly increase with annealing temperature. [ABSTRACT FROM AUTHOR]

In order to improve the thermal shock resistance of MgO-based ceramics, aluminum titanate (Al 2 TiO 5)-toughened MgO-based ceramics were successfully prepared by solid state sintering at 1450 °C and 1550 °C for 3 h starting from MgO and as-synthesized Al 2 TiO 5 powders. The effects of various contents of Al 2 TiO 5 second phase on the sintering behavior and thermal shock resistance of MgO-based ceramics were investigated. The sintering behavior of sintered samples was evaluated by comparing the relative density, apparent porosity, bending strength, phase composition as well as microstructure. The thermal shock resistance of sintered samples was characterized by using the residual bending strength after three thermal cycles and thermal expansion coefficient. The obtained samples with 10 wt% Al 2 TiO 5 , which were sintered at 1550 °C for 3 h, showed the highest relative density, lowest apparent porosity as well as optimum bending strength. In addition, the samples added 15 wt% Al 2 TiO 5 at 1550 °C with a dwell time of 3 h were the highest residual bending strength and lowest thermal expansion coefficient. It revealed that the enhancement in thermal shock resistance was ascribed to the reduction of thermal expansion coefficient. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to prospectively investigate the value of real-time ultrasound elastography (RTE) for the diagnosis of liver fibrosis (LF) in patients with chronic hepatitis B (CHB), to correlate the elastography findings with the histologic stage of LF and to compare RTE findings with those from noninvasive tests of LF calculated using laboratory blood parameters.Methods: Liver biopsies, laboratory blood testing, and RTE were performed in 91 patients with CHB. The LF index (LFI) was calculated using a multiple linear regression equation involving 11 parameters, which represented the degree of LF. The higher the LFI is, the greater the degree of LF.Results: The mean aspartate aminotransferase-to-platelet ratio index (APRI) and the mean fibrosis index based on four factors (FIB-4) were significantly different for the 5 stages of LF, respectively. The APRI (r = 0.43, P = 0.006), FIB-4 (r = 0.51, P = 0.012) and LFI (r = 0.562, P = 0.004) were correlated with the stages of LF. For discriminating stage F0 from F1, only the LFI had significant power (P = 0.026) for predicting stage F1. For discriminating stage F4 from F3, only the LFI had statistically significant power (P = 0.024) in predicting stage F4. The areas under the receiver operating characteristic curves (AUCs) of the LFI for diagnosing significant, advanced LF and liver cirrhosis were significantly higher than those of the APRI and FIB-4, and the LFI had better sensitivity and specificity.Conclusions: The LFI calculated by RTE is reliable for the assessment of LF in patients with CHB and has better discrimination power than the APRI and FIB-4. [ABSTRACT FROM AUTHOR]

Bone morphogenetic protein (BMP) signaling plays a vital role in differentiation, organogenesis, and various cell processes. As a member of TGF‐β superfamily, the BMP initiation usually accompanies crosstalk with other signaling pathways and simultaneously activates some of them. It is quite challenging to solely initiate an individual pathway. In this study, an opsin‐free optical method to specifically activate BMP receptors (BMPR) and subsequent pSmad1/5/8 cascades by a single‐time scan of a tightly‐focused femtosecond laser in the near infrared range is reported. Via transient two‐photon excitation to intrinsic local flavins near the cell membrane, the photoactivation drives conformational changes of preformed BMPR complexes to enable their bonding and phosphorylation of the GS domain in BMPR‐I by BMPR‐II. The pSmad1/5/8 signaling is initiated by this method, while p38 and pSmad2 are rarely perturbed. Based on a microscopic system, primary adipose‐derived stem cells in an area of 420 × 420 µm2 are photoactivated by a single‐time laser scanning for 1.5 s and exhibit pSmad1/5/8 upregulation and osteoblastic differentiation after 21 days. Hence, an opsin‐free, specific, and noninvasive optical method to initiate BMP signaling, easily accomplished by a two‐photon microscope system is reported. [ABSTRACT FROM AUTHOR]

The diffusion of point defects in passivation determines all physico-electrochemical processes in materials corrosion and protection. In this study, a multiscale quantitative methodology was developed to reveal the diffusivity of oxygen vacancies on titanium surface (～5.0 nm thickness) in 1.0 M H 2 SO 4 solution based on X-ray absorption fine structure (XAFS), combining with electrochemical impedance spectroscopy (EIS) and Mott-Schottky. EIS equivalent circuit exhibits that the high electronic field across passive film is 1.06 × 106 V cm–1. Mott-Schottky space charge capacitance indicates n-type semiconducting film with the donor density of ～1021 cm–3. Three important structure parameters have been firstly proposed from XAFS theoretical calculation at Ti K-edge to quantitatively describe the point defects transport between metal/film/solution interfaces. The half-jump distance equals half Ti–Ti distance subtly changing with oxidation potentials. The coordination coefficient is defined as the probability of activation jump from Ti–O coordination. And the Debye-Waller factor of structure disorder is related to the donor density of Mott-Schottky. Overall, the diffusivity of oxygen vacancies is in the range of (1.84–4.71) × 10–17 cm2 s–1 under the electric field, which determines the interfacial equilibrium of passivation and dissolution during potentiodynamic polarization. And the activation energy for motion has a minimum of 0.89 eV at 1.5 V. This multiscale quantitative methodology predicts well the potential dependent steady-state in the corrosive system. Image 10485 • XAFS was innovatively used for quantitative passivation kinetics analysis. • EIS and Mott-Schottky were related to local fine structure to estimate diffusion. • Three atomic structure parameters were firstly proposed for point defect transport. • Transport of oxygen vacancies at metal/film/solution interfaces was constructed. • The diffusivity of oxygen vacancies was more accurately calculated. [ABSTRACT FROM AUTHOR]

Abstract Phenylenediamine (PDA) was chosen as a coordinating, reducing, and capping agent to effectively direct growth and protect against oxidation of Cu nanowires (Cu NWs) in an aqueous solution. PDA was found to reduce Cu (II) to Cu (I) at room temperature, and stabilize the resulting Cu (I) by forming a coordination complex. The presence of a stable, intermediate Cu (I) complex is an essential step in the synthesis of Cu NWs under mild conditions. Incorporation of different PDA isomers leads to different growth paths of forming Cu NWs. Both p PDA and m PDA-synthesized Cu NWs are covered with a thin layer of polyphenylenediamine and show excellent oxidation-resistant in boiling water (3 days), and long-term stability in water at room temperature (10 months). The polyPDA-coated Cu NWs are electrochemically active even after a long-term storage in water. The usefulness of the oxidation-resistant electrochemical-active Cu NWs prepared here for a variety of nanotechnology applications is discussed. Graphical abstract Unlabelled Image Highlights • Cu nanowire/polyphenylenediamine core/shell structures were first time synthesized under a mild condition by forming a Cu (I) intermediate. • As-synthesized Cu nanowires show excellent oxidation-resistant in boiling water (3 days), and long-term stability in water at room temperature (10 months). • As-synthesized Cu nanowires are electrochemically active even after 10 months of storage in water. [ABSTRACT FROM AUTHOR]

The slag resistance of MgO–SiC–C (MSC) refractories should be improved because of the mismatch in the thermal expansion coefficient between the aggregates and matrix, as well as the defects caused by the affinity between periclase and slag. In this study, MgO–Mg 2 SiO 4 –SiC–C (MMSC) refractories were prepared using porous multiphase MgO–Mg 2 SiO 4 (M-M 2 S) aggregates to replace dense fused magnesia aggregates. Compared to MSC, the slag penetration index of MMSC decreased by 43.5%. The structure of the porous aggregates increased the surface roughness, and the multiphase composition of the aggregates decreased the mismatch of the thermal expansion coefficient with the matrix, thus reducing debonding between the aggregates and matrix. The aggregates and matrix in the MMSC formed an interlocking structure, which bound them more tightly to improve the slag resistance. The slag viscosity at different depths from the initial slag/refractory interface was calculated using the Ribond model. The M-M 2 S aggregates increased Si x O y z− in the slag, which increased the slag polymerization and slag viscosity. The aggregates and matrix in the MMSC reacted with the slag to form high melting point phases, which reduced the channel of the slag. In addition, the penetration depth and velocity derived from the Washburn Equation were modified for the CaO–SiO 2 –Al 2 O 3 –MgO–FeO slag and magnesia based refractory to accurately evaluate slag penetration. [ABSTRACT FROM AUTHOR]

To improve the service life of periclase-forsterite refractories, it is important to develop aggregates with high thermal shock resistance. In this study, periclase-forsterite aggregates with good resistance to thermal shock and micro-nanopores were prepared using high-silicon magnesite, silica, and silica sol. Microcracks were generated in the multiphase aggregates, which inhibited the continuous propagation of cracks during thermal shock through mismatched thermal expansion coefficients. Based on Hasselman's thermal shock stability factor, the reduction in the average thermal expansion coefficient and improved mechanical characteristics were critical factors in improving the thermal shock resistance of the multiphase aggregates. As a binder, silica sol provided nano-SiO 2 and superplasticity, which facilitated the formation of micro-nanopores and strengthened the combination of the various phases in the aggregates. [ABSTRACT FROM AUTHOR]

Two downward negative flashes (F1612 & F1613) with multiple return strokes struck to the 356-m Shenzhen Tower were analyzed. The high-speed camera captured upward positive connecting leaders (UCL) for the first strokes of both flashes and two subsequent strokes of F1612. The observations also show that none of the downward negative leader (DNL) completely propagated to the tower tip before the occurrence of the return stroke (RS), so that we inferred that the UCL initiated from the tower tip might exist for each RS of the two flashes. The possible height of the UCL and DNL connecting point above the tower tip for each RS was estimated, which showed a positive correlation to the speed of corresponding DNL. The striking distances estimated for 8 subsequent RSs in F1612 were in a range from 14.6 m to 85.4 m and that for 3 subsequent RSs in F1613 were from 24.2 m to 66.2 m. There was a weak positive linear relationship between the DNL speed and striking distance for subsequent RSs in the two flashes. The DNL speed showed a positive correlation to the peak current of corresponding RS. • Two negative flashes with multiple return strokes to a tall tower were studied based on high-speed camera measurements. • Upward connecting leaders from the tower tip were observed for the first time for two subsequent return strokes of a flash. • Heights of upward and downward leader connecting points showed a positive correlation to the downward leader speeds. [ABSTRACT FROM AUTHOR]

The self-healing of passive film on Ti after being damaged in Hank's physiological solution greatly fluctuates with time and its mechanism has been investigated by in-situ X-ray absorption fine structure spectroscopy (XAFS) and surface enhanced Raman spectroscopy (SERS) in a novel electrochemical repassivation set-up. The self-healing response is instant and the current density decays within 50 s due to the increase of the ratio of O and Ti atoms. The increase of the coordination number of Ti O contributes to the decrease of current density until 6000 s. Moreover, the in-situ structure evolution is vastly different from that of ex-situ. Two time-dependent adsorbed intermediates exist during self-healing, the adsorption layers of Ti OH ads and Ti OH, and finally the interface forms a stable passive film of O Ti OH after 1000 s with good corrosion resistance. Besides, in-situ XAFS and SERS exhibit a high disorder and amorphous nature of passive film on Ti, and the crystallinity increases from 300 s to 6000 s. Additionally, the time-dependent structure evolution and mechanism of self-healing of titanium passive film in local atomic scale will help to understand the corrosion science and protection in healthcare. Unlabelled Image • A new electrochemical repassivation setup was designed for in-situ XAFS and SERS. • Two adsorbed intermediates in the initial stage during self-healing were found. • High disorder passive film with O–Ti–OH on Ti has good corrosion resistance. [ABSTRACT FROM AUTHOR]