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Designing the high-performance, high-subsonic airfoils suitable for different Reynolds number flow is the major challenge for high-altitude long-endurance drones and ultra-high altitude solar aircraft. To overcome the difficulties, this paper proposed a set of aerodynamic optimization design methods that combine the improved category shape function transformation method, parallel computational fluid dynamics, and an improved whale optimization algorithm. This approach achieves high modeling accuracy, computational efficiency, and strong optimization ability. Verification using single-peak, multi-peak, and fixed-dimensional test functions demonstrates that the improved whale optimization algorithm has significantly enhanced optimization capabilities compared with the conventional whale optimization, particle swarm optimization, and gravity search algorithms. Numerical simulations are used to analyze the internal flow mechanisms before and after airfoil optimization under different Reynolds numbers. The results show that, compared with the original airfoil, the optimized airfoil has front loading characteristics that effectively reduce the adverse pressure gradient of the rear part of suction surface, promoting the transition in this region. The reduced adverse pressure gradient also inhibits the development and growth of laminar separation bubbles and slows down the growth of the boundary layer displacement thickness, thereby reducing wake mixing loss and improving the aerodynamic performance. [ABSTRACT FROM AUTHOR]

A novel extension of the basis reduction method for kinematic hardening shakedown problem is presented. Firstly, the basis reduction method is implemented based on the modified Newton–Raphson (N-R) method. Then a new technique for the construction of back stress field is introduced, where the simultaneous influence of multiple load corners in shakedown is taken into consideration. Finally, two typical numerical examples are investigated. The results compared with previous works in literatures demonstrated that the proposed method is accurate and the performance in reducing of computation time is significant. [ABSTRACT FROM PUBLISHER]

A capacitive immunosensor on a glassy carbon electrode (GCE) was fabricated successfully by using an insulating poly (o-phenylenediamine) (OPD) film. Two methods, covalently coupling and copolymerization, were developed to immobilize the antitransferrin onto the GCE for sensitively probing transferrin. The capacitance change of the electrode caused by the interaction between antigen–antibody was monitored by the potentiostatic step. The immunosensors demonstrated a highly specific response to transferrin in a sample solution. The stable insulating property of the OPD film made immunosensor renewable in acid elution. For the immunosensor fabricated by the covalently coupling method, the linear detection range was 0.1 to 45.0 ng/mL, with a detection limit of 0.061 ng/mL (S/N = 3). For immunosensor fabricated by the copolymerization method, the linear detection range was 5.0 to 17.5 ng/mL, with a detection limit of 2.0 ng/mL. This indicated that the immunosensor prepared by the covalently coupling method showed better sensitivity and a wider detection range than one fabricated by the copolymerization method. Compared with self-assembled monolayers, the method of using the insulating OPD film simplified the process of immunosensor fabrication and provided a new approach to prepare capacitive immunosensor on carbon substrate. [ABSTRACT FROM AUTHOR]

In this paper, an analytical closed-form solution for Mode-I energy release rate of an adhesively bonded sandwich beam is derived from the modified elastic foundation model. For validation purpose, a model based on the finite element method (FEM) was also constructed using the modified crack closure integral technique to calculate the compliance and Mode-I energy release rate of the sandwich beam. Comparison between the closed-form solution and the FEM solution showed a good agreement. The results of calculations also showed a significant effect of the adhesive layer of the sandwich beam on fracture analysis. This means that the effect of the adhesive layer of the sandwich beam cannot be ignored. [ABSTRACT FROM AUTHOR]

Dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) is associated with recurrent pulmonary infections and inflammation. We previously reported that tumor necrosis factor (TNF)-α decreases gap junction connectivity in cell lines derived from the airway epithelium of non-cystic fibrosis (non-CF) subjects, a mechanism that was defective in cells derived from CF patients, and identified the tyrosine kinase c-Src as a possible bridge between TNF-α and Cx43. To examine whether this modulation also takes place in primary epithelial cells, the functional expression of Cx43 was studied in non-CF and CF airway cells, obtained from surgical polypectomies and turbinectomies, which were grown either on culture dishes or permeable filters. Expression of Cx43 was detected by immunofluorescence on cells grown under both culture conditions. Non-CF and CF airway cells also showed intercellular diffusion of Lucifer Yellow. Dye coupling was rapidly abolished in non-CF cells in the presence of TNF-α, lipopolysaccharide and lysophosphatidic acid, and could be prevented by tyrphostin47, an inhibitor of Src tyrosine kinases. This down-regulation, however, was not detected in CF airway cells. These data indicate that CFTR dysfunction is associated with altered Src signaling, resulting in the persistence of gap junction connectivity in primary and transformed CF airway cells. [ABSTRACT FROM AUTHOR]

Ambient particles may cause pulmonary inflammation with ensuing morbidity. Particle-induced production of proinflammatory cytokines in vitro has been used as an indicator of particle toxicity. To identify particle components that were related to particle toxicity, Andersen dichotomous impactors were used to collect ambient fine (PM[sub 2.5]) and coarse (PM[sub 2.5-10]) particles in central Taiwan with extraction in endotoxin-free water. Mouse mono-cyte-macrophage cell line RAW 264.7 cells were exposed to particle extracts at 40 µg/ml for 16 h, and tumor necrosis factor-alpha (TNF-α) was measured in the medium by enzyme-linked immunosorbent assay (ELISA). Cell viabilities were all greater than 82%. Coarse particles stimulated higher TNF-αproduction than fine particles, and this was associated with greater particulate endotoxin content. Polymyxin B inhibited 42% of TNF-α production elicited by coarse particles and 32% of TNF-α production elicited by fine particles. In fine particles, TNF-α production was negatively correlated with Zn content, while no element in coarse particles correlated with TNF-α production. Results suggest that endotoxin and other components may be important factors for TNF-α production by macrophages in vitro. [ABSTRACT FROM AUTHOR]

Distributed pulsating flow planar tube bundle heat exchanger (DPFPTB-HE) can improve heat transfer and have a high prospect of application in the industry. Computational fluid dynamics (CFD) software Fluent was utilized as an analysis tool, and the factors affecting heat transfer in heat exchangers were comprehensively studied based on the theory of fluid mechanics and heat transfer in this article. The local average surface Nusselt number(Nuv) evaluated the heat transfer performance. Results found that the DPFPTB-HE proposed in this paper has more uniform distribution of cold fluid in the shell domain and higher heat transfer efficiency in each layer of the tube bundle compared with the conventional planar tube bundle heat exchanger (PTB-HE). In this paper's single-factor analysis experimental session, the study showed that with the inlet velocity increases, Nuv increases; as the length of the branch pipe increases, Nuv decreases; branch pipe diameter increases, Nuv decreases. The results obtained Nuv by applying the optimal experimental parameters selected by the Taguchi method were 7.22% larger than the maximum value in the control group. The numerical result and methodology are beneficial for providing further insight into guiding the optimization of heat exchanger structure and promoting industrial progress. [ABSTRACT FROM AUTHOR]

Exploration of host–guest complexation between a shape-persistent H-bonded macrocycle and flexible guests may enable construction of new pseudorotaxanes systems. Here, we present the impact of varying the spacer length of four bis(4-phenylpyridinium) guests G1-G4 on production of pseudorotaxanes with a 2D H-bonded macrocycle 1a. The host–guest complexes are probed by 1H NMR, 2D NOESY and UV–vis spectroscopic techniques. [2]- and [3]- pseudorotaxane assemblies are formed specifically using these guests, demonstrating the dependency of accessing [2]- and [3]- pseudorotaxane on the spacer length of these dications. Theoretical calculations reveal the difference in the conformation of the guests between these two binding modes: the one with a 1:1 stoichiometry (spacer length: C4 and C6) show Z-shaped conformation and the other with a 2:1 stoichiometry (spacer length: C8 and C10) take a linear conformation. The findings of the threading modes may help develop new H-bonded macrocycle-based rotaxanes and other related mechanically interlocked molecules. [ABSTRACT FROM AUTHOR]

Two bisdiglycolamides (BisDGAs) ofN,N,N′′′,N′′′-tetrabutyl-Nʹ,N′′-ethidene bisdiglycolamide (TBE-BisDGA) andN,N,N′′′,N′′′-tetrabutyl-Nʹ,N′′-m-xylylene bisdiglycolamide (TBX-BisDGA) were synthesized. Their extraction behaviors of Eu(III) and Am(III), as well as nitric acid were investigated from nitric acid medium by using n-octanol as diluent. Nitric acid is extracted as the form of HNO3·(BisDGAs)0.6by BisDGAs and the conditional acid uptake constants of TBE-BisDGA and TBX-BisDGA were 0.26 and 0.10, respectively. The distribution ratios of Eu(III) and Am(III) increased with the increase of nitric acid and extractant concentration, whilst decreased with temperature rise. TBX-BisDGA had a stronger extraction power for Eu(III) and Am(III) than TBE-BisDGA. Both of the extractants displayed a higher affinity toward Eu(III) than Am(III). In the examination of the acidity range from 0.5 to 5.0 M, a maximum separation factor SFEu(III)/Am(III)can reach 8.0 at 3.0 M HNO3for TBX-BisDGA; and 10 at 4.0 M HNO3for TBE-BisDGA, respectively. Slope analyses showed that Eu(III) and Am(III) are extracted as di-solvated species by TBX-BisDGA or TBE-BisDGA. The extraction mechanism was described and the apparent extraction equilibrium constant as well as Gibbs free energy change, enthalpy change and entropy change were presented. In addition, their Eu(III) complexes were analyzed by using infrared spectra. [ABSTRACT FROM PUBLISHER]

The further development of fishery resources is a hotspot in the development of the fishery industry. However, how to develop aquatic animal resources deeply is a key point to be solved in the fishery industry. Over the past decades, numerous aquatic animals have gained great attention in the development and utilization of their bioactive molecules which are of therapeutic applications as nutraceuticals and pharmaceuticals. Recent research revealed that aquatic animals are composed of many vital moieties, such as polysaccharides and proteins, which provide health benefits beyond basic nutrition. In particular, aquatic animal polysaccharides are gaining worldwide popularity owing to their high content, ease of extraction, specific structure, few side effects, prominent therapeutic potential and incorporation in functional foods and dietary supplements. Thus, tremendous research on the isolation, identification and bioactivities of polysaccharides has been carried out. This review presents comprehensive viewpoints on extraction, separation, purification, structural characterization and bioactivity of various polysaccharides from aquatic animals, such as sea cucumber, abalone, oyster and mussels. In addition, this review profiled a brief knowledge on both current challenges and future scope in aquatic animal polysaccharides field. The review will be a direction of deep processing in fishery resources, which is a hotspot, but technical bottleneck. Furthermore, the review could be served as a useful reference material for further investigation, production and application of polysaccharides from aquatic animals in functional foods and therapeutic agents. [ABSTRACT FROM AUTHOR]

Human rights indicators are tools for monitoring a government's progress in fulfilling its human right obligations. In 2012, the United Nations released a manual of human rights indicators that includes a conceptual framework and illustrative indicators. This article reports on an examination of “right to work” indicators appropriate for use in Taiwan. The review was undertaken under the auspices of the executive branch of the government of Taiwan in consultation with panels of experts, officials of statistical departments, and persons from vulnerable groups, to contextualize the indicators for future implementation. The authors modified several indicators suggested in the manual and created one additional attribute on collective labor rights. Following an analysis of the indicators, the article highlights several issues that require further attention, including the feasibility of disaggregating administrative data, the use of indicators at subnational levels of governments, and the development of human rights indicators for particular groups. [ABSTRACT FROM AUTHOR]

This article focuses on the buckling of cylindrical shells with stepwise variable thickness subjected to uniform external pressure. First, combining the method of separation of variables, perturbation method, and Fourier series expansion, an analytical method for the buckling analysis of cylindrical shells with axisymmetric thickness variation subjected to external pressure is established. The method is verified by comparing with the previous results. Then, the stepwise variable thickness of cylindrical shells is described exactly by the arc tangent function. Finally, using the presented method, a general formula for the critical buckling load of cylindrical shells with stepwise variable thickness subjected to uniform external pressure is derived. This general formula is compared and discussed with some empirical formulae in the current design standards. This study lays a theoretical foundation for the calculation of the buckling load of cylindrical shells with stepwise variable thickness subjected to uniform external pressure. Moreover, it provides a reference and guidance for the further revision of related standards. [ABSTRACT FROM PUBLISHER]

The Chung-an ground lizard Takydromus sylvaticus is an endemic and long-lost reptile species in China. In this study, its mitochondrial genome (mitogenome) sequence was firstly determined by long PCR and primer walking methods. The genome is 17,838 bp long and contains 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 2 main noncoding regions (the control region and the putative L-strand replication origin). The gene order and contents in the T. sylvaticus mitogenome is identical to that found in typical vertebrates, suggesting that it represents an ancestral arrangement. Within the control region, typical conserved domains and distinct repeat regions were identified. [ABSTRACT FROM AUTHOR]

1. The aim was to investigate the phenotype distribution characteristic and gender-related differences of CYP2E1 activity in a healthy Chinese population. 2. Two hundred and three healthy Chinese subjects (105 men, 98 women) were enrolled in this study. 3. CYP2E1 activity was determined by plasma 6-hydroxychlorzoxazone-to-chlorzoxazone concentration ratio (CHZ-MR) 4h after chlorzoxazone dosing. The concentrations of 6-hydroxychlorzoxazone and chlorzoxazone in plasma were detected by reversed-phase HPLC. 4. The results showed an almost 9-fold variation of CYP2E1 activity at a range of from 0.23 to 1.99. The coefficient of variation CY % was demonstrated with skewness and kurtosis of the ratios in the studied population were 44%, 0.96 and 1.10, respectively. 5. CYP2E1 activity was normally distributed in logarithmic form of 6-OH-CHZ/CHZ as evaluated by Kolmogorov-Smirnov test of normality (p = 0.20). Probit plots of the CYP2E1 activity index of men shifted to the right as compared with that of women. The mean CHZ-MR in men was significantly higher than that in women (0.76 ± 0.30 versus 0.60 ± 0.28, p < 0.001), and this difference still existed when normalized by weight (0.73 ± 0.28 versus 0.66 ± 0.32, p = 0.016). Body weight correlated positively with CYP2E1 activity in the total group(r < 0.212, p < 0.01). [ABSTRACT FROM AUTHOR]