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A facile strategy without organic template was developed for the conversion of fly ash to LTA-type zeolite (LTA-Z), which could be used as a good adsorbent for the removal of acid fuchsin (AF). XRD results indicated that the pure crystalline product was obtained with the structure of LTA-type zeolite. SEM investigations showed that the well-defined LTA-Z crystals exhibited uniform size with the same cubic shape. The maximum AF adsorption amount was observed at pH=5, slightly lower than pH of LTA-Z. Higher temperature favored AF adsorption onto LTA-Z and it was an endothermic process. Furthermore, AF adsorption amount increased with initial AF concentration increasing and LTA-Z dosage decreasing. Surface sorption governed this process at the initial 120 min period, followed by the internal diffusion of AF molecules between porous sites. The Langmuir model was determined as the adsorption isothermal, suggesting that the monolayer coverage of AF on LTA-Z surface was involved. [ABSTRACT FROM AUTHOR]

• Doping of 0.1 at.% Y inhibits surface crystallization of a melt-spun Fe 87 Hf 5 B 8 ribbon. • The annealed Y-doped alloys form a uniform and fine nanostructure in the whole ribbons. • The Y-doped nanocrystalline alloys exhibit reduced H c but maintain high B s. A Fe 87 Hf 5 B 8 alloy forms a crystallization layer with textured coarse α-Fe grains in the free surface of the melt-spun amorphous ribbon, which deteriorates the uniformity of nanocrystalline structure after annealing and leads to a high coercivity (H c) of over 16 A/m. Doping of 0.1–0.2 at.% Y into the Fe 87 Hf 5 B 8 alloy inhibits the surface crystallization of the melt-spun precursor and contributes to a uniform and fine nanostructure in the whole annealed ribbons. The Y-doped nanocrystalline alloys possess lower H c of around 9 A/m and maintain high saturation magnetic flux density of 1.70 T. The suppression of the surface crystallization by Y doping is attributed to the improvement of amorphous-forming ability, which is mainly caused by the reduction of oxygen impurity content in the alloys. [ABSTRACT FROM AUTHOR]

Abstract: In this paper a novel finger mechanism with 1 active DOF is proposed for an underactuated operation. The underacuation mechanism design is based on spring elements within the mechanism structure. The feasibility of the mechanism is verified through suitable kinematic and static analysis to give performance characteristics. The finger mechanism is able to obtain a human-like grasping operation and it can be embedded within the finger body with human-size mechanical design. The proposed finger mechanism is presented also as obtained from a synthesis procedure which is based on the analyzed characteristics. A design solution is proposed and tested through numerical simulation. [Copyright &y& Elsevier]

Abstract: In this paper, we present the effect of payload collision on the dynamics and control of a flexible dual-arm space robot capturing an object. The dynamics model of the robot system is derived with Lagrangian formulation. The two flexible links are modeled as Euler–Bernoulli beams with two bending modes each. Initial conditions are derived from the impact model to simulate the post-impact dynamics of the whole systems. A PD controller is designed, whose purpose is to maintain stabilization of the robot system after the capture of the object. The dynamical simulations are carried out in two cases: the robot system is uncontrolled and controlled after impact. The simulation result shows that impact effect of the object on the space robot is great. It also shows that the joint angles of base and manipulators quickly reach steady state through feedback control. [Copyright &y& Elsevier]

Human intestinal epithelial cell monolayers (Caco-2) subjected to hypoxia and reoxygenation release soluble factors into the apical medium that activate the virulence of the opportunistic pathogen Pseudomonas aeruginosa to express the potent barrier-dysregulating protein PA-I lectin/adhesin. In this study, we defined the role of hypoxia-inducible factor (HIF)-la in this response. We tested the ability of medium from Caco-2 cells with forced expression of HIF-1α to increase PA-I expression in P. aeruginosa and found that medium from Caco-2 cells overexpressing HIF-1α increased PA-I expression compared with medium from control cells (P < 0.001, ANOVA). To identify the components responsible for this response, medium was fractionated by molecular weight and subjected to mass spectroscopy, which identified adenosine as the possible mediator. Both adenosine and its immediate downstream metabolite inosine induced PA-I expression in P. aeruginosa in a dose-dependent fashion. Because inosine was not detectable in the medium of Caco-2 cells exposed to hypoxia or overexpressing HIF-1α, we hypothesized that P. aeruginosa itself might metabolize adenosine to inosine. Using mutant and parental strains of P. aeruginosa, we demonstrated that P. aeruginosa metabolized adenosine to inosine via adenosine deaminase and that the conditioned medium enhanced the extracellular accumulation of mosine. Together, these results provide evidence that P. aeruginosa can recognize and respond to extracellular end products of intestinal hypoxia that are released after activation of HIF-1α. The ability of P. aeruginosa to metabolize adenosine to inosine may represent a subversive microbial virulence strategy that deprives the epithelium of the cytoprotective actions of adenosine. [ABSTRACT FROM AUTHOR]

Abstract: Expression of Cry1Ab protein in Bt transgenic rice (KMD) and its residue in the rhizosphere soil during the whole growth in field, as well as degradation of the protein from KMD straw in five soils under laboratory incubation were studied. The residue of Cry1Ab protein in KMD rhizosphere soil was undetectable (below the limit of 0.5ng/gair-dried soil). The Cry1Ab protein contents in the shoot and root of KMD were 3.23–8.22 and 0.68–0.89μg/g (fresh weight), respectively. The half-lives of the Cry1Ab protein in the soils amended with KMD straw (4%, w/w) ranged from 11.5 to 34.3d. The residence time of the protein varied significantly in a Fluvio-marine yellow loamy soil amended with KMD straw at the rate of 3, 4 and 7%, with half-lives of 9.9, 13.8 and 18d, respectively. In addition, an extraction method for Cry1Ab protein in soil was developed, with extraction efficiencies of 46.4–82.3%. [Copyright &y& Elsevier]

It is generally reasoned that lethal infections caused by opportunistic pathogens develop permissively by invading a host that is both physiologically stressed and immunologically compromised. However, an alternative hypothesis might be that opportunistic pathogens actively sense alterations in host immune function and respond by enhancing their virulence phenotype. We demonstrate that interferon-γ binds to an outer membrane protein in Pseudomonas aeruginosa, OprF, resulting in the expression of a quorum-sensing dependent virulence determinant, the PA-1 lectin. These observations provide details of the mechanisms by which prokaryotic organisms are directly signaled by immune activation in their eukaryotic host. [ABSTRACT FROM AUTHOR]

In this paper, the enhanced photonic spin hall effect (PSHE) of reflected light at terahertz (THz) frequencies is achieved by using a multilayer structure consisting of Bi 2 Se 3 , spacer layer, and distributed Bragg reflector structure. This enhanced spin hall effect (SHE) phenomenon originates from the excitation of optical Tamm states (OTSs) at the interface between the Bi 2 Se 3 and distributed Bragg reflector structure. It is found that the PSHE of the reflected light can be flexibly controlled by properly varying the Fermi energy of the topological insulators. Moreover, the spin behavior of the composite structure is also proved sensitive to incidence angle and the dispersion characteristics of the spacer layer, thus making this configuration an effective candidate for developing photonic devices based on photonic PSHE at the terahertz range. [ABSTRACT FROM AUTHOR]

• High B s nanocrystalline alloy was developed by adding Cu and Nb to a Fe 87 B 13 alloy. • Melt-spun and crystallized structure can be tuned by changing Cu and Nb contents. • Competitive growth of pre-existing α-Fe and Nb-inhibited atoms diffusion lead to refined structure. • Fe 83.3 B 13 Cu 1.7 Nb 2 nanocrystalline alloy with finest α-Fe grains has a high B s of 1.75 T and low H c of 9.5 A/m. The effects of Cu and Nb additions on the structure and magnetic properties of a Fe 87 B 13 alloy in melt-spun and annealed states were investigated. Increase in Cu content from 1.0 to 1.7 at.% changes the melt-spun Fe 87-x B 13 Cu x alloy ribbons from a single amorphous phase to a composite of high-number-density nano-order α-Fe phase with an average grain size (D α-Fe) of 12.1 nm dispersing in the amorphous matrix. The crystallized structure after annealing gets refined with increasing the Cu content, and a small D α-Fe of 18.1 nm is obtained for the Fe 85.3 B 13 Cu 1.7 alloy, which possesses a low coercivity (H c) of 32.6 A/m and high saturation magnetic flux density (B s) of 1.87 T. Minor addition of Nb reduces the D α-Fe in melt-spun Fe 85.3-y B 13 Cu 1.7 Nb y alloys but not obviously lowers the number density, while 3 at.% Nb makes the formation of fully amorphous phase. The D α-Fe in the crystallized alloys is decreased to 15.3 nm by alloying 2 at.% Nb, but increased to 31.4 nm with 3 at.% Nb. The Fe 83.3 B 13 Cu 1.7 Nb 2 nanocrystalline alloy exhibits a lower H c of 9.5 A/m combined with high B s and effective permeability at 1 kHz of 1.75 T and 15000, respectively. The combined effects of competitive growth of the pre-existing nano-order α-Fe particles and Nb-inhibited atoms diffusion contribute to the refinement of the nanocrystalline structure. [ABSTRACT FROM AUTHOR]

Based on uniaxial and triaxial compression tests, the present study investigates the mechanical properties of high-strength concrete (HSC), ultrahigh-strength concrete (UHSC) and the corresponding mortars with the same mix proportions of the matrixes of two types of concretes. The tests recorded the mechanical responses including peak stress, axial strain at peak point and failure modes of HSC, UHSC and mortars specimens. The test results show that the compressive strength and deformation capacity of concretes and mortars gradually grow higher with the increasing of confining pressure, and the enhancement of confining pressure on the compressive strength of mortar is significantly lower than that of concrete. For HSC and UHSC, the enhancement on compressive strength has a negative relationship with the uniaxial compressive strength and similar relationship is also found between the two types of mortars. Compared with the mortar, the increase in confining pressure can, to some extent, better enhance the deformation capacity of concrete. There are three failure modes of concretes and mortars under the confining pressure: vertical splitting failure, oblique shear failure and extrusion flow failure. Confining pressure has very little effects on the initial tangent modulus, the initial tangent modulus of the two types of concretes is larger than that of corresponding mortars, and the addition of coarse aggregate can improve the tangent modulus of HSC more significantly than UHSC. Failure surfaces for concretes and mortars under triaxial stress were identified by using the four-parameter failure criterion. [ABSTRACT FROM AUTHOR]

• The active pocket of Pmi LAAD was probed by iterative mutagenesis. • The L-Amino acid deaminase activity of Pmi LAAD was enhanced by semi-saturated mutagenesis. • The K m , k cat , k cat / K m of Pmi LAAD-SAVS variant were better (−42.7%, 75.11%, and 85.79%) than that of Pmi LAAD wild type. • Pmi LAAD-SAVS has been applied to enzymatic synthesis of α-keto acids. In our previous study, we produced α-keto acids by using an L-amino acid deaminase Pmi LAAD (wide-type) from Proteus mirabilis, however, the catalytic efficiency was low due to its low substrate affinity. In this study, protein engineering of Pmi LAAD was performed to improve the α-keto acid production. Pmi LAAD was engineered by iterative CASTing to improve its catalytic performance. The four mutant Pmi LAAD-SAVS (Pmi LAAD-Phe93Ser-Pro186Ala- Met394Val-Phe184Ser) with 6.6 -fold higher specific activity compared with that of wild-type Pmi LAAD has been obtained by high-throughput screening. Comparative kinetics analysis showed that the four mutant Pmi LAAD-SAVS had a higher substrate-binding affinity and catalytic efficiency than that of Pmi LAAD wild-type. The K m , k cat , and k cat / K m values of the Pmi LAAD(SAVS) variant was better (-42.7%, 75.11%, and 85.79%, respectively) than the corresponding values of Pmi LAAD wild type. Finally, the whole cell biocatalyst E. coli -pETDuet-1- Pmi LAAD(SAVS) has been applied to α-keto acids production. The conversion rate of L-phenylalanine reached 99% by whole-cell biocatalyst E. coli -pETDuet-1- Pmi LAAD(SAVS). The conversion of (D/L)-4-phenylalanine was reached 49.5% after 7 h by whole-cell biocatalyst E. coli -pETDuet-1- Pmi LAAD(SAVS), while the conversion of E. coli -pETDuet-1- Pmi LAAD (wild type) was only 18% after an extension of the reaction time (24 h). This study has developed a robust whole-cell E. coli biocatalyst for α-keto acids production by protein engineering, and this strategy may be useful for the construction of other biotransformation biocatalysts. [ABSTRACT FROM AUTHOR]

Monitoring the thermal behavior of distributed energy resources (DERs) network explores the dualism between thermal effects and electrical power flow. This paper proposes a design concept that monitors thermal conditions of DER grids, using ZigBee/GSM wireless sensor networks (WSNs) for real-time monitoring in rural and remote areas. The concept seeks to improve upon existing designs by integrating composite functions. The functions comprise temperature conditions monitoring, data acquisition, and wireless data transmission including data storage and abnormal conditions alert/notification for control solutions. Thus, the concept determines the thermal impact on the DERs integrated network. WSNs with temperature sensors LM35 are utilized to complement ZigBee and Global System for Mobile Communications (GSM) technologies as a communication assisted link. Temperatures are measured from solar Photovoltaic PV modules, wind turbine, distribution cables, protection control units, and energy storage facilities. The ATMEGA328P microcontroller is assigned for signal and control processing. The circuit performance is coordinated and displayed on an LCD screen for normal conditions, whereas abnormal scenarios communicate through an alert/notification by GSM Short Message Service (SMS) protocol. The development analysis was performed through algorithm and circuit simulations. Proteus software was used for circuit design. Both the algorithm and circuit analysis passed the assigned simulation stages. [ABSTRACT FROM AUTHOR]