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A highly inducible promoter capable of actively expressing exogenous genes in diatoms is critical to further improving the utility of this organism as a low-cost platform for industrial applications. In this study, the functional promoter of alkaline phosphatase gene in Phaeodactylum tricornutum ( PtAPase ) was used to develop a novel vector. The pPhAP1-EGFP vector containing the putative promoter region of PtAPase (pPhAP1) with EGFP (enhanced green fluorescent protein) open reading frame attached to downstream side. Transgenic diatom clones containing the introduced pPhAP1-EGFP vector did not express EGFP fluorescent at high phosphate concentration, and exhibit growth curves similar to that of wild type strain. EGFP fluorescent was induced and actively expressed when ambient phosphate concentration was decreased to 3.6 μM or lower. The endogenous alkaline phosphatase activity had the same expression pattern, indicating that the pPhAP1 possessed uncompromised regulatory capability. In terms of the quantity of EGFP generated by expression vectors, the yield of pPhAP1-EGFP was 9.3 to 10.5 times greater than those of other diatom vectors. These results suggested that pPhAP1 is an outstanding expression vector for diatoms with desirable characteristics of no interference with algal growth, easily tunable conditions for gene induction, and high yield of recombinant proteins.

The world&rsquo, s first natural avian-origin H6N1 influenza A virus infection case in dogs was confirmed in Taiwan in 2014. The H6N1 virus in chickens has been endemic in Taiwan since 1972. Whether the dog H6N1 virus has interspecies transmission potential is the key issue we aim to understand. Following one virus passage in embryonated eggs and two further passages in MDCK cells, we obtained two virus derivatives, E01EE (PB1 739E and PB2 627E) and E01GK (PB1 739G and PB2 627K), respectively. The pathogenicity of E01EE and E01GK was investigated using plaque assay, growth dynamic analysis and cell viability quantification in cells from different animal species. The impact of amino acid mutation on PB1 739 and PB2 627 on viral ribonucleoprotein (RNP) activity was also analyzed. Further mouse infection experiments were performed. The results showed that both E01EE and E01GK decreased cell relative viability of canine MDCK cells, human A549 cells and chicken DF1 cells. E01Gk caused greater cellular harm in MDCK and A549 cells and had significantly higher virus titers in all of the cells compared to E01EE. The PB2 627K but not PB1 739G was the critical mutation that influenced the viral RNP activity. Both E01EE and E01GK caused mice pneumonia and considerable virus shedding, especially E01GK. This report verifies PB2 E627K mutation in virulence and spotlights the potential for the dog H6N1 virus to extend interspecies transmission.

This study proposes a newflight route-planning technique for autonomous navigation of unmanned aerial vehicles (UAVs) based on the combination of evolutionary algorithms with virtual potential fields. By combining a radial forcefieldwith a swirling forcefield, three-dimensional virtual potentialfields are constructed for repelling infeasible UAV flight routes from threatening zones. To ensure feasibility, major flight constraints are considered when searching for the optimal flight route. This study examines both singleand multiple-obstacle cases to determine the efficiency of the proposed flight route planner. The UAV navigation method uses an offline planner in known environments and an online planner for flight route replanning when popup threats emerge. Both planners were tested under various scenarios. The results show that the proposed planner can efficiently enable the safe navigation of UAVs.

A new method is proposed to deal with the dual-axis control of a multi-variables system with two induction motors. Investigation of resolving the cross-coupling problem of dual-axis platform is addressed by a neural net-based decoupling compensator and a sufficient condition ensuring closed-loop stability is derived. An evolutionary algorithm processing the universal seeking capability is proposed for finding the optimal connecting weights of the neural decoupling compensator and the gains of PID controllers. Extensive numerical studies verify the performance and applicability of the proposed design under a variety of operating conditions.

This paper presents a new approach which consists of a fuzzified eigensystem realization algorithm (FERA) to identify the parameters of the designed mini-UAV model performance in the low speed wind tunnel (LSWT) power on testing system. On the basis of the identification scheme, it is able to reduce system operational cost of wind tunnel tests and provide a tool for predicting results without resorting to on-site experiments. A variety of variables in model types and testing environment such as model profile, angle of attack, elevator, tunnel wind speed and power system (motor and propeller) are considered. The method based on logic devices is simple yet effective. The results obtained are compared to those obtained by the conventional wind-tunnel testing method. To verify effectiveness of the proposed methodology, both of simulations and real-world experiments are conducted. The results show that the working performance of the proposed method correlates well with expectation.

This paper presents the realization of a microbrushless dc motor (MBDCM) feedback system based on a real-coded structural genetic algorithm (RSGA), which combines the advantages of conventional real genetic algorithms and structured genetic algorithms for optimal control design. In the RSGA, a dynamic crossover and mutation probability adjusting method mimicking the characteristics of Butterworth filters is proposed to enhance the search performance. A SinCos encoder with a line drive of 128 sin/cos signals per revolution is implemented to achieve precise positioning. The SinCos encoder possesses the advantage of high resolution via signal interpolation. The method inherited is simple yet effective, based on logic devices. To verify effectiveness of the proposed methodology, simulations are conducted and an experimental platform with a digital signal processing unit, a motor driver, a MBDCM, and a SinCos encoder is built to verify applicability of the proposed method. The experimental results demonstrating the aforementioned method work properties correlate well with the expectation.

This paper develops an innovative optimization method, real structured genetic algorithm (RSGA), which combines the advantages of traditional real genetic algorithm (RGA) with structured genetic algorithm (SGA), and applies it for digital filter and control design optimization problems. For infinite impulse response (IIR) filter designs, the proposed approach fulfills all types of filters by minimizing the order of the filter and the absolute error of both passband and stopband. Both system structure and parametric variables are simultaneously optimized via the proposed chromosome scheme. The approach has also been extended to deal with robust control design problems. The approach offers an effective method for designing an optimal controller with robust stability. Simulation and experimental results conveys the excellence of the proposed algorithm over traditional approaches in convergence speed, performance, cost effectiveness, and attains simpler structure.

A DNA computing algorithm (DNACA) with an electron-ion interaction potential (EIIP) decoding scheme is proposed to identify a class of transfer functions. The DNACA includes enzyme and virus operators which provide a highly modular, flexible, and accurate self-organizing structure environment. Simulation study based on De Jong's test functions show its superior performance when compared with the improved and standard genetic algorithms (GAs).

The relationship between serum vascular adhesion protein-1 (VAP-1) and plasma glucose in normal and drug-naïve type 2 diabetes subjects is unclear. We examined if serum VAP-1 changed acutely to oral glucose loading and analyzed the relationship between serum VAP-1, fasting plasma glucose (FPG), hemoglobin A1c, and type 2 diabetes.Adults without history of diabetes were included. Subjects taking anti-diabetic drugs were excluded. Serum VAP-1 was analyzed by time-resolved immunofluorometric assay.We recruited 333 subjects (186 females and 147 males), aged 56.1 +/- 11.6 y. After glucose challenge, serum VAP-1 rose significantly at 30 min (p0.0001) and lasted until 2 h (p0.0001). The change of serum VAP-1 between fasting and 30-min postload correlated inversely to the change of plasma insulin (r = -0.21, p = 0.049). Fasting serum VAP-1 was associated with FPG in those with FPGor = 5.55 mmol/l (p = 0.025) but not in those with FPG5.55 mmol/l (p = NS). Fasting serum VAP-1 were higher in diabetic subjects (p = 0.04) and correlated positively to hemoglobin A1c (r = 0.18, p = 0.002) after adjusting for age, gender, and waist circumference.Serum VAP-1 is increased in both acute and chronic hyperglycemia. Whether serum VAP-1 is a good biomarker for hyperglycemia-associated complications merits further investigation.

This paper presents a new approach to deal with the dual-axis control design problem for a mechatronic platform. The cross-coupling effect leading to contour errors is effectively resolved by incorporating a neural net-based decoupling compensator. Conditions for robust stability are derived to ensure the closed-loop system stability with the decoupling compensator. An evolutionary algorithm possessing the universal solution seeking capability is proposed for finding the optimal connecting weights of the neural compensator and PID control gains for the X and Y axis control loops. Numerical studies and a real-world experiment for a watch cambered surface polishing platform have verified performance and applicability of our proposed design.

This paper develops a path planning simulation method in AGI software platform for multirotor UAVs in a 3D environment with avoiding the obstacles is presented. A multi-RRT (rapidly exploring random tree, RRT) algorithm is applied to compute the preliminary flight paths.

Optimized path planning algorithm design is an important function of unmanned aerial vehicles (UAVs). Since the path obtained by the (rapidly exploring random tree) RRT is not necessarily optimal, excessive waypoints need to be refined. Heading of the quadrotor UAV is considered here as a moving cost of the improved A-star algorithm. Since the secondary path generated by the improved A-star algorithm is piecewise linear and may exhibit rugged curvature, it's necessary to refine the flight path making it to be applicable for quadrotor UAV flight. The proposed path planning method has been well verified via a variety of scenarios.

Polyesters containing thiolate chain end were obtained from the “controlled” ring-opening polymerization (ROP) of e-caprolactone or δ-valerolactone initiated by several novel aluminum thiolates. The initiators, [(MOBT)2AlR] (1, R = Me; 2, R = Cl) can be obtained in high yield from the interaction of Me3Al or Et2AlCl with 2 molar equiv of 2-methoxybenzenethiol (MOBT-H). [(μ-TMBM)AlR2]2 (3, R = Et; 4, R = Me; 5, R = Bui) were prepared from the reactions of R3Al with 1 molar equiv of 2,4,6-trimethylbenzylmercaptan (TMBM−H) in dichloromethane at ambient temperature. The X-ray structures of 1−3 have been determined and have shown that 1 and 2 are monomeric while 3 is dimeric in the solid state. The “controlled” character of the aluminum complex shown in the polymerization process has enabled us to synthesize a P-δ-VL-b-P-e-CL block copolymer, and the thioester end group may provide a suitable method for the design of PCL conjugates. In addition, ROP of l-lactide initiated by 1 can be achieved under refluxing t...

The reaction of 2-methoxybenzyl alcohol with one molar equiv of R2AIX in diethyl ether at 0°C gives [(2-MeOC6H4CH2-μ-O)AlRX]2 (1: R = Et, X = Cl, 2: R = X = Et). In addition, 2,4-di-tert-butylphenol reacts with iBu3Al affording a four-coordinated aluminum compound [(μ-2,4-tBu2-C6H4O)Al(iBu)2]2 (4). Single crystal X-ray structure analysis of 4 shows a C2h-symmetry with a planar Al2O2 core. Ring-opening polymerization (ROP) of caprolactones initiated by 1, 4 and [(μ-OCH2C6H4OMe)Al(iBu)2]2 (3) is performed and polyesters with narrow molecular weight distributions were obtained from the “living” ROP of caprolactones. 1H NMR spectroscopic studies of PCL reveal that the initiator of 1 and 3 is through the Al-OAr function, but the initiator of 4 is through the Al- iBu group.

A mathematical programming model is proposed in this paper for determining the optimal water usage and treatment network (WUTN) in any chemical plant, which features the least amount of fresh water consumption and/or minimum wastewater treatment capacity. In particular, because design equations of all wastewater treatment facilities and all units which utilize either process or utility water are included in the model, more comprehensive integration on a plant-wide scale can be achieved. In comparison with the available technologies, the proposed method is more reliable, more accurate, and much faster in synthesizing the WUTNs. Furthermore, more cost-efficient alternatives may be identified in certain design cases.

The proteasome subunit beta type 8 gene (PSMB8) encodes one of the beta subunits of the immunoproteasome responsible for the generation of peptides presented by major histocompatibility complex class I molecules. Dimorphic alleles of the PSMB8 gene, termed A and F types, based on the deduced 31st amino acid residue of the mature protein have been reported from various vertebrates. Phylogenetic analysis revealed the presence of dichotomous ancient lineages, one comprising the F-type PSMB8 of basal ray-finned fishes, and the other comprising the A-type PSMB8 of these animals and both the F- and A-type PSMB8 of Xenopus and acanthopterygians, indicating that evolutionary history of the PSMB8 dimorphism was not straightforward. We analyzed the PSMB8 gene of five reptile and one amphibian species and found both the A and F types from all six. Phylogenetic analysis indicated that the PSMB8 F type was apparently regenerated from the PSMB8 A type at least five times independently during tetrapod evolution. Genomic typing of wild individuals of geckos and newts indicated that the frequencies of the A- and F-type alleles are not highly biased in these species. Phylogenetic analysis of each exon of the reptile PSMB8 gene suggested interallelic sequence homogenization as a possible evolutionary mechanism for the apparent recurrent regeneration of PSMB8 dimorphism in tetrapods. An extremely strong balancing selection acting on PSMB8 dimorphism was implicated in an unprecedented pattern of allele evolution.

This paper studied the point stabilization problem for a constrained autonomous lawnmower. A constrained kinetic model is established first. The authors proposed a backstepping adaptive controller to solve the stabilizing control design problem. The proposed approach has been numerically verified.