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Developing low-temperature co-fired MLAs for the commercial application of micro-nano actuation and manipulation has recently become a research highlight. To simultaneously achieve high piezoelectric response and low co-firing temperature below 960 °C, a PNN-PZT-0.02 Sr piezoceramic incorporated with Li 2 O-Bi 2 O 3 -CuO sintering additives and its MLA with the dimension of 7×7×3 mm3 were prepared using tape-casting and subsequent co-firing methods. The piezoceramic mainly composed of a triple phase (M, R, and T) co-existence shows a dense microstructure, indicating a good sintering-assistance effect. Even sintering at 920 °C, the piezoceramic possesses d 33 ∼ 683 pC/N and k p ∼ 0.64, possibly surpassing most reported PZT-based piezoceramics. The MLA co-fired at 940 °C possesses a good Ag-ceramic interface without holes, aggregation or delamination. Also, it shows high maximum displacement (≥ 20 μm), high stiffness (118.5 N/μm @ 150 V), excellent thermal stability and 109-cycle reliability. A flat and defect-free electrode morphology is conducive to decreased leakage current. However, high tanδ primarily induced by the residual glassy phase and (Pb, Bi) oxides is the drawback. These findings give a novel paradigm for low-cost and high-reliability MLAs using pure Ag as inner electrodes by triple-phase controlling and nano-heterogeneity. • A PNN-PZT piezoceramic sintered at 920 °C possessed desirable electrical properties, d 33 ∼ 683 pC/N and k p ∼ 0.64. • High piezoelectric response originated from triple multi-phase coexistence and nano heterogeneity. • A low-cost MLA with pure Ag as the inner electrodes was achieved using low-temperature co-fire. • A 109-cycle reliability is comparable to that of the commercial Pd-contained counterparts. [ABSTRACT FROM AUTHOR]

Esculentoside A (EsA) is a saponin isolated from the roots of Phytolacca esculenta . This study was designed to evaluate the pharmacological effects of EsA on lipopolysaccharide (LPS)-stimulated BV2 microglia and primary microglia cells. Our results indicated that EsA pretreatment significantly decreased LPS-induced production of Nitric Oxide (NO) and Prostaglandin E2 (PGE2) and impeded LPS-mediated upregulation of pro-inflammatory mediators' expression such as nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-12 (IL-12) and tumor necrosis factor-a (TNF-α) in both BV2 microglia and primary microglia cells. Moreover, EsA markedly suppressed nuclear factor-κB p65 (NF-κB p65) translocation by blocking IκB-α phosphorylation and degradation in LPS-treated BV2 cells. EsA also decreased phosphorylation level of mitogen-activated protein kinases (MAPKs) and inhibited NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome mediated caspase-1 activation in LPS-stimulated BV2 cells. Additionally, EsA decreased β-amyloid 1–42 (Aβ 1–42 )-induced production of TNF-α, IL-1β and IL-6 in primary microglia. Thus, EsA might be a promising therapeutic agent for alleviating neuroinflammatory diseases. [ABSTRACT FROM AUTHOR]

Abstract: The influence of Ca2+ on the aggregation of sodium dodecyl sulfate (SDS), sodium dodecyl oxyethylene sulfate (SDES), sodium dodecyl benzene sulfate (SDBS) and sodium dodecyl benzene oxyethylene sulfate (SDBES) at air–water interface were compared to investigate the role of oxyethylene unit by means of the molecular dynamics simulation. In the SDES and SDBES systems, the interaction between h name="sbnd" />SO3 − groups and Na+ions decreases, the diffusion coefficient of Na+ increases, while the interaction between surfactants and Ca2+ ions increases, and the diffusion coefficient of Ca2+ ions decreases. Unlike SDS and SDBS systems, the EO groups introduced may bind Ca2+ ions and the interaction between Ca2+ ions h name="sbnd" />SO3 − groups is weakened, consequently, the precipitation of anionic surfactant by Ca2+ ion is restrained, i.e., the Ca2+-tolerance of anionic surfactants via the introduction of EO groups may be improved. The present results could help in choosing of anionic surfactants used in aqueous solution with inorganic salts. [Copyright &y& Elsevier]

Abstract: A lipase from Candida rugosa (CRL) has been immobilized in mesoporous rod-like silica and vesicle-like (or onion-like) silica supports by physical adsorption. The mesostructures and characteristics of the two mesoporous materials before and after adsorption of CRL were characterized by HRTEM, FESEM, SAXRD and N2 adsorption–desorption experiments. The pore sizes of the rod-like silica and the vesicle-like silicas were determined to be ca. 11 and 12nm, respectively, larger than enough to accommodate lipase molecules (∼4nm). The structural integrity of the rod-like silica as well as the vesicle-like silica is retained after adsorption of CRL into the mesopores. The catalytic activity, thermostability, and operational stability of the immobilized CRL were measured in phosphate buffer solution by hydrolysis of tributyrin. When the lipase immobilized in the vesicle-like silica was used as biocatalyst for hydrolysis of tributyrin in a batch process, the hydrolysis activity decreased only slightly from 74% to 60% over 10 cycles of reuse, indicating no obvious leaching out of the lipase from the round channels. The activity of vesicle-like silica immobilized CRL for catalytic hydrolysis of tributyrin is 21% and 14% higher than that of rod-like silica immobilized CRL at incubation temperature of 60°C at 30min and 90min, respectively. The results demonstrate that the lipase immobilized in vesicle-like silica is superior to the rod-like silica in terms of higher activity, reusability and thermal stability. The unique curvature and the large size of the interlamellar pores of vesicle-like silica are suggested to be possible factors in achieving the higher activity and stability. Such a distinctive mesoporous geometry of the vesicle-like silica promises technological applications in protein adsorption and catalysis. [Copyright &y& Elsevier]

Inflammation and coagulation are two important processes implicated in venous thromboembolism (VTE). 15-epi-lipoxin A 4 (15-epi-LXA 4) is the epimer of LXA 4 , a small lipid molecule, is known to play a key role in the resolution of inflammation. This study aimed to demonstrate whether 15-epi-LXA 4 could suppress the inflammatory factor tumor necrosis factor-alpha (TNF-α)-induced upregulation of tissue factor (TF), an important regulator of the blood coagulation cascade, and evaluated the possible underlying mechanisms. We found that 15-epi-LXA 4 not only reduced the up-regulation of mRNA and antigens, but also lowered the activity of TF (elevated by TNF-α) in primary culture of human umbilical vein endothelial cells (pc-HUVECs). In addition, 15-epi-LXA 4 suppressed the activation of the phosphoinositide 3-kinase (PI3K)/AKT signaling pathway, induced by TNF-α, in pc-HUVECs. 15-epi-LXA 4 also inhibited the binding of NF-κB on the TF promoter, which is otherwise enhanced by TNF-α. The role of 15-epi-LXA 4 in regulating TNF-α-induced effects was enhanced by the PI3K inhibitor and prevented by the PI3K activator. In conclusion, 15-epi-LXA 4 lowered the TNF-α-induced high TF expression and activity by suppressing PI3K/AKT signaling activation, thereby reducing the binding capacity of NF-κB on the TF promoter in pc-HUVECs. [ABSTRACT FROM AUTHOR]

Using high temperature CO 2 sorbent for carbon capture is an effective approach to reduce carbon footprint. Copper slag, as an abundant metallurgical waste containing substantial amount of Si and Fe resources, was being explored as cheap raw material for the preparation of lithium-based sorbent. The results shows that the lithiation is initiated at 450–600 °C, where fayalite and magnetite in slag are firstly oxidized by released water vapor from the decomposition of LiOH, then further react with Li 2 O to form Li 4 SiO 4 and LiFeO 2. As the temperature rises, the conversion of LiFeO 2 to Li 5 FeO 4 and incorporation of Fe3+, Al3+ into Li 4 SiO 4 lattice occur in parallel. The resulting sorbent exhibited excellent CO 2 chemisorption ability with a capture capacity of 420 mg/g material at 725 °C. Particularly, even in the gas stream containing 5 vol% CO 2 , it showed a CO 2 uptake capacity of 383 mg/g material. In the CO 2 cycling tests, the sorbent suffered a decay in sorption capacity, which was ascribed to the poor regeneration ability of Li 5 FeO 4. Comparatively, it possesses a relatively high capacity of 241 mg/g material in 20 vol% CO 2 after 20 cycles, which is higher than those of previously reported Li-silicate sorbents derived from wastes. [ABSTRACT FROM AUTHOR]

Abstract: Calcium carbonate (CaCO3) was crystallized in (2-hydroxypropyl-3-butoxy) propyl-succinyl chitosan (HBP-SCCHS) solutions by a slow vapor diffusion method. The CaCO3 crystals were characterized by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetry analysis (TGA) and N2 adsorption–desorption methods. By varying the concentrations of HBP-SCCHS and Ca2+, temperature and initial pH, the CaCO3 crystals with different morphologies were obtained. Based on the analysis of CaCO3 crystals obtained under different conditions, the mechanisms of the CaCO3 crystallization in the presence of HBP-SCCHS were proposed. It was found that the adsorption of HBP-SCCHS molecules on CaCO3 surfaces played a key role in the formation of CaCO3. [Copyright &y& Elsevier]

Abstract: Calcium carbonate (CaCO3) was crystallized in the presence of O-carboxymethylchitosan (CMCS) by a vapor diffusion method. The CaCO3 particles were characterized by scanning electron microscopy (SEM), the energy dispersion spectroscopies (EDS), powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetry analysis (TGA) and N2 adsorption–desorption methods. By varying the concentrations of CMCS, Ca2+ and Mg2+ ions, and temperature, the CaCO3 nanocrystals with different morphologies were produced. Based on the analysis of CaCO3 particles obtained under different conditions, the mechanism of the CaCO3 crystallization in the presence of CMCS was proposed. [ABSTRACT FROM AUTHOR]

Background: Gait speed is recognized to correlate to knee kinematic alterations. Clinically, patients with knee diseases tend to walk slowly compared to healthy controls. Hence, gait speed may serve as a confounding factor in the kinematic characteristics of patients during gait compared to healthy controls.Research Question: Whether and how gait speed affects six degrees of freedom (6DOF) knee kinematics remains unclear. The current study was designed to explore whether and how decreased gait speeds affect 6DOF knee kinematics.Methods: Thirty subjects (15 males and 15 females) were recruited for this study. A three-dimensional gait analysis system was used to assess the 6DOF knee kinematics of subjects at gait speeds of 4.0 km/h, 3.5 km/h, 3.0 km/h, 2.5 km/h, 2.0 km/h, 1.5 km/h, and 1.0 km/h. Kinematics of gait cycle (GC) were assessed at all gait speed levels.Results: Decreased adduction angle (0.5-3.2 °, p < 0.05), increased external rotation (0.6-3.3 °, p < 0.05) and decreased flexion angle (1.5-17.4 °, p < 0.05) were found during most GC as gait speed level decreased. Greater anterior tibial translation (0.9-2.6 mm, p < 0.05), greater proximal translation (0.4-2.4 mm, p < 0.05) and decreased lateral tibial translation (0.5-3.0 mm, p < 0.05) were found during most GC as gait speed level decreased. Gender was also found to have great effects on 6DOF knee kinematics (p < 0.05). Interactions between gender and gait speed were also found (p < 0.05).Significance: Our findings suggest that additional attention should be paid when dealing with kinematic comparisons of GC between controls and patients with significantly different gait speeds or genders than controls. Kinematic alterations induced by gait speed may raise concern for patients with knee diseases who struggle to walk faster than their normal speed. This may enhance our knowledge of the relationship between gait speed and 6DOF knee kinematics. [ABSTRACT FROM AUTHOR]

Abstract: Rheological properties of welan gum and xanthan gum solutions have been characterized systematically at various concentrations, temperatures and salinities. It is found that the viscoelasticity of welan gum is higher than that of xanthan gum at the same condition though the molecular weight of welan gum is lower. In view of this, welan gum will make a good performance in enhanced oil recovery, especially in high temperature and high salinity reservoirs. Network structure can be formed in solutions of welan gum and xanthan gum for the dynamic modulus has exponential relationship with the concentration. Moreover, the molecular aggregates of welan gum adopt a different arrangement with that of xanthan gum, adjacent double helices of welan gum arrange in parallel as the zipper model. The structure formed by zipper model is still stable in high temperature and high salinity. [Copyright &y& Elsevier]

Abstract: The aggregation behavior of a star-like amphiphilic block copolymer (denoted as AP432, which was synthesized via anionic polymerization), in aqueous solutions was investigated by surface tension, steady-state fluorescence, dynamic light scattering (DLS) and transmission electron microscopy (TEM). For comparison, a commercially available linear amphiphilic PEO–PPO–PEO block copolymer, Pluronics L64, which has a similar PEO fraction to AP432, was also studied. It is found that the different molecular structure of AP432 and L64 leads to a significant difference on their behavior both at the air/water interface and in bulk aqueous solutions. The results of surface tension measurements indicate that the surface activity of AP432 is much more pronounced than that of L64. The formation of AP432 and L64 aggregates are identified by DLS, fluorescence and TEM measurement. [Copyright &y& Elsevier]

Abstract: The aggregation behavior of fluorinated surfactant in aqueous solution was investigated using dissipative particle dynamics (DPD) simulation method. Simulation results show that fluorinated surfactants behave mainly as their hydrocarbon analogues, having similar sequences of phases and aggregate structures, which are capable of building micelle, hexagonal phase and lamellar phase. But fluorinated surfactants also show interesting differences from hydrocarbon analogues, which can easily form hexagonal and lamellar structures with comparative little curvature. They can also form ellipsoid or rod-like micelles even in very low concentrations instead of spheroid ones. The dynamic aggregation behavior of fluorinated surfactants, as well as the comparison with hydrogenated ones, was also investigated. [Copyright &y& Elsevier]

Overexpression of the acrAB genes regulated by RamA and overexpression of oqxAB regulated by RarA have been reported to mediate multidrug resistance in Gram-negative bacilli. In this study, regulation of acrAB and oqxAB simultaneously by the global regulator RamA was investigated in a multidrug-resistant Klebsiella pneumoniae clinical isolate (KP22) resistant to tigecycline and other antimicrobials. KP22 overexpressed ramA due to a ramR mutation, along with an unexpected overexpression of oqxB. Deletion of ramA led to a 16-fold decrease in the tigecycline minimum inhibitory concentration (MIC) with decreased expression of acrB (4.3-fold) and oqxB (7.1-fold) compared with KP22. Transcomplementation of KP22Δ ramA with the wild-type ramA gene restored the tigecycline MIC and upregulation of the acrB (3.9-fold) and oqxB (4.0-fold) genes compared with KP22. When oqxB was knocked out, MICs of ciprofloxacin, olaquindox and nitrofurantoin were considerably decreased, while deletion of acrB led to MIC decreases for cefepime, piperacillin/tazobactam and tigecycline in addition to the above three antimicrobials. The results of electrophoretic mobility shift assay showed that RamA could bind the promoter regions of both the acrAB and oqxAB operons. This study demonstrates for the first time that RamA can directly regulate multidrug resistance efflux pumps AcrAB and OqxAB in K. pneumoniae. [ABSTRACT FROM AUTHOR]