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Rendezvous and docking (RVD) with a tumbling target is challenging. In this paper, a novel control scheme based on motion planning and pose (position and attitude) tracking is proposed to solve the pose control of a chaser docking with a tumbling target in the phase of close range rendezvous. Firstly, the current desired motion of the chaser is planned according to the motion of the target. In planning the desired motion, the “approach path constraint” is considered to avoid collisions between the chaser and the target, and the “field-of-view constraint” is considered to make sure the vision sensors on the chaser to obtain tight relative pose knowledge of the target with respect to the chaser. Then, the difference between the chaser’s motion and the desired motion is gradually reduced by a pose tracking controller. This controller is based on the non-singular terminal sliding mode (NTSM) method to make the tracking error converge to zero in finite time. Since the chaser nearly moves along the desired motion and the motion is reasonable, (1) it could safely arrive at the docking port of the target with a suitable relative attitude, (2) it will be always suitably oriented to observe the target well, and (3) the magnitude of the needed control inputs are less than that in existing literatures. The numerical results demonstrate the above three advantages of the proposed method.

This paper studies the pose tracking control problem for satellite proximity operations between a target and a chaser satellite, by which we mean that the chaser is required to track a desired time-varying trajectory given in advance with respect to the target. Firstly, by consulting an adaptive sliding-mode control method in literature developed for a class of nonlinear uncertain systems, an effective pose tracking controller is obtained. This controller requires no information about the mass and inertia matrix of the chaser, and takes into account the gravitational acceleration, the gravity-gradient torque, the J2 perturbing acceleration, and unknown bounded disturbance forces and torques. Then, an updated controller is proposed by combining the aforementioned controller and the unscented Kalman filter (UKF). This updated controller estimates the inertial parameters of the chaser through UKF, so it is of better adaptive ability to the initial estimation of the inertial parameters. Finally, numerical simulations are given to demonstrate the effectiveness of the proposed controllers. The simulation results show that the updated controller is more accurate.

Space debris is generally a kind of tumbling noncooperative space target which poses a serious threat to human space activities. In active debris removal (ADR) missions, capturing a space target directly may cause damage to space manipulator and chaser satellite, so it is a feasible strategy to reduce the angular velocity of space target to an acceptable range in the pre-capture phase. In this paper, an active detumbling technology for a free-floating tumbling space target with energy dissipation is studied, and an effective detumbling method utilizing intermittent contact impact between the space target and despin mechanism is proposed. First, the dynamic model of the space target is set up by the Jourdain’s velocity variation principle. Then, a contact model between the space target and despin mechanism is established based on the Hertz contact theory and the method of computer graphics. Finally, the detumbling method is validated by numerical simulations. Simulation results show that our method can reduce the angular velocity of the space target effectively without causing large nutation.

Capturing an uncontrolled space target is a tremendously challenging research topic. Target capture by a space robot can be well planned according to predicted motion of the target. In this paper, motion prediction of an uncontrolled space target is studied and a motion prediction algorithm is proposed. In the proposed algorithm, firstly a method for identifying the parameters of motion state and inertial property of the target is established; and then through substituting the identified parameters into the dynamic equations of the target, the motion of the target can be predicted as the solution of the equations. In the identification of the parameters, the unscented Kalman filter (UKF) is applied. In order to support the UKF, a method for estimating noise level of the observation data is developed, so our motion prediction algorithm is noise adaptive. A practical convergent criterion is also designed to determine the time when the estimated result of the UKF is accurate enough, such that the predicted motion is credible enough. After that, the accuracy of the prediction is further improved by an optimization method. In the end of this paper, numerical simulations are done to verify the validity of the proposed motion prediction algorithm. Simulation results indicate that the proposed algorithm is able to predict the motion of the target precisely.

High-performance and multifunctional epoxy resins (EPs) are of great use in the booming electric & electronic and 5G fields, however their fabrication shows huge challenges. Herein, through a facile strategy by simply incorporating a functional molecule DPI (phosphaphenanthrene polyethylenimine), which possessed a unique structure with hyperbranched polyethyleneimine as flexible inner core and phosphaphenanthrene groups as rigid outer shell, a high-performance and multifunctional epoxy resin was successfully fabricated. The hyperbranched rigid-flexible structure of DPI endowed the resultant thermoset EP-DPI with superb mechanical performance and high glass transition temperature, for which, at a low DPI content (≤4 wt%), EP-DPI exhibited 160%, 40%, and 31% improvement in impact toughness, tensile strength, and flexural strength compared with neat EP. At the same time, the good compatibility between DPI and the EP matrix enabled EP-DPI to be highly transparent, and the aromatic phosphorus structure endowed EP-DPI with excellent UV-shielding effect in the UV-A band. The dielectric performance of EP-DPI was enhanced due to the unique structure of DPI and its interaction with the EP matrix. Furthermore, the phosphaphenanthrene groups endowed EP-DPI with excellent anti-ignition, self-extinguishing, and low heat release during combustion. This work opens up a new strategy for developing novel high-performance and multifunctional EPs with potential versatile applications.

The use of conventional flame-retardant elements such as Cl, Br, P for carbon-based polymers usually leads to the deterioration of smoke and toxic gas release, and possesses serious environmental and ecological issues. Herein, we proposed a facile strategy to largely improve the flame-retardant efficiency of an eco-friendly flame-retardant method. By simply tailoring the substitution position of the functional polymerization monomer, the corresponding copolymer exhibited extremely high flame retardancy, including a 59% lower peak heat release rate (pHRR), a 48% lower smoke density, a high limiting oxygen index (LOI) of 30%, and passed the UL-94 V-0 rating without dripping. More importantly, the para-substitution copolymer showed a much higher flame-retardant efficiency than the meta-substitution copolymer, for which the monomer content needed for UL-94 V-0 rating, high LOI value, and low smoke and toxic gas release largely decreased by 25%. The detailed mechanism and the different performance between the two copolymers were comprehensively investigated. The results first confirmed the “end-group-capturing” mechanism, then revealed that the different flame-retardant efficiency was owing to the different thermal rearrangement capability of the two functional monomers. The molecular-level mechanism revealed here provided a novel thinking for designing flame-retardant polymers.

New bifunctional primary amine-squaramides catalyzed asymmetric Michael addition reaction of α,α-disubstituted aldehydes to maleimides has been developed. This organocatalytic asymmetric reaction provides easy access to functionalized succinimides with a broad substrate scope. Both enantiomers of desired succinimide derivatives were obtained in good to excellent yields (up to 98%) with excellent enantioselectivities (up to >99% ee).

Despite the excellent overall performance, the application of polyesters is severely restricted by their inherently high flammability. Although many gratifying results have been achieved through different fire-safety methods, customization is still needed for every specific polymer, thus a generally applicable method is highly desired. Herein, we developed an eco-friendly and general fire-safety method for semi-aromatic polyesters based on the “end-group-capturing” concept. The functional monomer was chemically incorporated into the main chains of a series of semi-aromatic polyesters with similar structures (i.e., polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT) and polybutylene terephthalate (PBT)), and the specific contribution of the fire-safety method was investigated comprehensively. The results showed that the fire safety of all the copolyesters were efficiently improved, while interestingly, the fire safety gradually declined with the increase of the methylene group numbers in their molecular chains. The reason behind this phenomenon was comprehensively studied by both theoretical calculation and experiments. The increasing cyclization tendency of the copolyesters derived from the increase of the methylene group numbers was proved to be responsible for the decrease of the fire safety. The successful application and in-depth mechanism revealed here provide theoretical supports for the development of novel fire-safety polymeric materials.

Different 0D, 1D and 2D carbon nanoparticles were added into a main chain liquid crystalline polyester (LCP) to investigate the effect of the nanoparticles on the shape memory behavior of LCP. Fullerene (C60), multi-wall carbon nanotube (CNT) and graphene (G) were selected as the fillers in an attempt to form π-π interaction with LCP chains, which acted as a physical crosslinking to obtain the increased shape recovery stress and recovery ratio. The composites were prepared by solution mixing. The formation of π-π interaction was investigated by wide angle X-ray diffraction (WXRD), fluorescence emission spectrometry and Raman laser spectrometry. Shape recovery stress and shape recovery ratio were recorded by dynamic mechanical analysis (DMA). Results indicated that C60 and CNT significantly augmented shape recovery ratio but had little effect on Shape recovery stress, while G diminished shape recovery ratio but improved the shape recovery stress.

Based on industrial electricity consumption, we model industrial networks by Granger causality method and MST (minimum spanning tree), and then further stick onto an industrial coupling mechanism from energy-consumption perspective. First, we construct Granger causality networks of five provinces in South China of GD, GX, GZ, HN and YN based on their industrial electricity consumption data, and we demonstrate from a network-topology perspective: the distribution of weight of links of all industrial electricity-consumption Granger causality networks approximately follows power-law distribution, revealing a phenomenon that few industries may bring a tremendous influence on the rest. Moreover, correlation analysis between weight and degree of a node shows that in most Granger causality networks, both span and strength of influence of a given industry will significantly increase. Further, we analyze the relationship between the thresholds of Granger causality significance and density of corresponding networks. Results show GD and HN could be classified into a group with relatively greater global differentiation in industries and unbalanced industrial development, however, GX, GZ and YN are grouped as second cluster with relatively balanced industrial development. Furthermore, using Chu–Liu–Edmonds MST algorithm, we extract graphs of MSTs or maximal cliques from industrial electricity-consumption Granger causality networks, and research on energy transmission structure, feedback loop, and bootstrap reliability. By analyzing MSTs, we find that only GD, GX and YN can be extracted with MST graphs, and capture the probable transmission routes of key nodes. Besides we illustrate all three MST graphs are involved with feedback loops structures with various characteristics: GX has complete feed-forward section, feed-back section and feedback loop section; YN has only feed-forward section and feedback loop section; GD has multiple feedback loops section. Finally, we conduct bootstrap reliability tests on MSTs. Results show branches of reliability of GD, GX and YN are decentralized while those feedback loops sections are only concentrated on highly-reliable branches. As neither HN nor GZ can be extracted with MST graphs, we characterize them by maximal cliques. It is demonstrated that both industrial systems of HN and GZ are significantly grouped into two independent branches and those internal industries inside independent branches are highly correlated. However from perspectives of whole South China, the causal relationship is only converged on a few of industries. For regions without MST graphs like HN and GZ, the reliability of links is also greater than that of GD, GX and YN.

In many kinds of on-orbit space robot tasks, capturing free floating target using space robot attracts more attention of researchers. However, most existing researches about dynamics and control of space robot concern planar problem, and the effect of flexible panel on capturing dynamics of the system is not considered. In this paper, spatial dynamics and control of a 6-DOF space robot with flexible panels are investigated and spatial impact problem is considered. Dynamic model of the system is established by the single direction recursive construction method and the Jourdain's velocity variation principle. The Hertz contact and impact theory and the method of computer graphics are used to establish the impact model. The computed torque control method is used to design active controller to suppress the spacecraft drift caused by the impact. Numerical simulation results show that the established dynamic model is effective in describing the dynamics behavior of the space robot; flexible panels have big influence on impact dynamic characteristics; the designed controller may effectively control the spacecraft drift during the capture process.

In this paper, deployment dynamics and control of large-scale flexible solar array system with deployable mast are investigated. The adopted solar array system is introduced firstly, including system configuration, deployable mast and solar arrays with several mechanisms. Then dynamic equation of the solar array system is established by the Jourdain velocity variation principle and a method for dynamics with topology changes is introduced. In addition, a PD controller with disturbance estimation is designed to eliminate the drift of spacecraft mainbody. Finally the validity of the dynamic model is verified through a comparison with ADAMS software and the deployment process and dynamic behavior of the system are studied in detail. Simulation results indicate that the proposed model is effective to describe the deployment dynamics of the large-scale flexible solar arrays and the proposed controller is practical to eliminate the drift of spacecraft mainbody.

Based on industrial electricity-consumption data of five southern provinces of China from 2005 to 2013, we study the industrial correlation mechanism with MST (minimal spanning tree) and HT (hierarchical tree) models. First, we comparatively analyze the industrial electricity-consumption correlation structure in pre-crisis and after-crisis period using MST model and Bootstrap technique of statistical reliability test of links. Results exhibit that all industrial electricity-consumption trees of five southern provinces of China in pre-crisis and after-crisis time are in formation of chain, and the “center–periphery structure” of those chain-like trees is consistent with industrial specialization in classical industrial chain theory. Additionally, the industrial structure of some provinces is reorganized and transferred in pre-crisis and after-crisis time. Further, the comparative analysis with hierarchical tree and Bootstrap technique demonstrates that as for both observations of GD and overall NF, the industrial electricity-consumption correlation is non-significant clustered in pre-crisis period, whereas it turns significant clustered in after-crisis time. Therefore we propose that in perspective of electricity-consumption, their industrial structures are directed to optimized organization and global correlation. Finally, the analysis of distance of HTs verifies that industrial reorganization and development may strengthen market integration, coordination and correlation of industrial production. Except GZ, other four provinces have a shorter distance of industrial electricity-consumption correlation in after-crisis period, revealing a better performance of regional specialization and integration.

Lactobacillus plantarum is an important probiotic and is mostly isolated from fermented foods. We sequenced the genome of L. plantarum strain 5-2, which was derived from fermented soybean isolated from Yunnan province, China. The strain was determined to contain 3114 genes. Fourteen complete insertion sequence (IS) elements were found in 5-2 chromosome. There were 24 DNA replication proteins and 76 DNA repair proteins in the 5-2 genome. Consistent with the classification of L. plantarum as a facultative heterofermentative lactobacillus, the 5-2 genome encodes key enzymes required for the EMP (Embden-Meyerhof-Parnas) and phosphoketolase (PK) pathways. Several components of the secretion machinery are found in the 5-2 genome, which was compared with L. plantarum ST-III, JDM1 and WCFS1. Most of the specific proteins in the four genomes appeared to be related to their prophage elements.

It is well known that friction is an inevitable phenomenon existing in almost all mechanical systems including robotic systems. Friction can harm dynamic characteristics of mechanical systems as well as the accuracy of manual control. In this paper, we have comprehensively investigated the dynamic process of a flexible space robot with joint friction. Dynamic equation of the system is established based on the Jourdain's velocity variation principle and the single direction recursive construction method. The Coulomb friction model and LuGre friction model are adopted to describe the joint friction. The calculation method for joint friction is discussed in detail. Moreover, an active controller is designed by the computed torque control method for trajectory tracking control. Simulation results indicate that the proposed model is effective in describing the dynamics response of the system. Joint friction can cause oscillation of the joint response and vibration of the flexible link, as well as affecting the precision of position control of the system. From the results we present, it can also be inferred that the Coulomb friction model is limited in describing the nonlinear features of friction.

Study Objective A novel pressure bladder indicator was developed, and this study aimed to evaluate the clinical application of the pressure bladder indicator by measuring the epidural space pressure and bladder working pressure on patients undergoing lumbar epidural puncture. Design Randomized, prospective, double-blinded study Patients 130 patients Setting The Second Hospital of Shandong University Interventions In this study, 60 patients undergoing surgical procedures under lumbar epidural anesthesia were enrolled to detect epidural pressure, and other 70 patients who were undergoing lumbar epidural anesthesia or combined spinal-epidural anesthesia were enrolled to evaluate the pressure bladder indicator. Measurements After successful breakthrough of ligamentum flavum by traditional methods, a pressure transducer was connected to an epidural needle tail and a monitor to measure the epidural pressure at L1-L5 in 60 patients. The working pressure of the bladder was also measured by a transducer. Then lumbar epidural puncture was performed with the pressure bladder indicator in other 70 patients. Main Results The lumbar epidural pressure of the 60 patients was 9.8 ± 4.3 mm Hg, and the bladder working pressure of the pressure bladder indicator was 122 ± 15 mm Hg. All these 70 patients were confirmed with successful bladder indication and lumbar epidural puncture. Thus, the coincidence ratio was 100%. Conclusions The novel developed pressure bladder indicator was a reliable and useful technique to conduct successful lumbar epidural puncture.

In the paper, we research on the characteristics of RMB exchange rate time series fluctuation with methods of symbolization and coarse gaining. First, based on fluctuation features of RMB exchange rate, we define the first type of fluctuation mode as one specific foreign currency against RMB in four days’ fluctuating situations, and the second type as four different foreign currencies against RMB in one day’s fluctuating situation. With the transforming method, we construct the unique-currency and multi-currency complex networks. Further, through analyzing the topological features including out-degree, betweenness centrality and clustering coefficient of fluctuation-mode complex networks, we find that the out-degree distribution of both types of fluctuation mode basically follows power-law distributions with exponents between 1 and 2. The further analysis reveals that the out-degree and the clustering coefficient generally obey the approximated negative correlation. With this result, we confirm previous observations showing that the RMB exchange rate exhibits a characteristic of long-range memory. Finally, we analyze the most probable transmission route of fluctuation modes, and provide probability prediction matrix. The transmission route for RMB exchange rate fluctuation modes exhibits the characteristics of partially closed loop, repeat and reversibility, which lays a solid foundation for predicting RMB exchange rate fluctuation patterns with large volume of data.

It is well known that friction is an inevitable phenomenon existing in almost all mechanical systems including robotic systems. It can affect dynamic characteristics of mechanical systems and even harm accuracy of manual control. In this paper, we have conducted comprehensive study in detail on dynamics and control of a space robot with joint friction. Dynamic equation of the system is established based on Jourdain׳s velocity variation principle and the single direction recursive construction method. The Coulomb friction model, the Stribeck friction model and the LuGre friction model are adopted to describe the joint friction. Meanwhile, the calculation method for joint friction is discussed in detail, and the relationship between ideal constraint force and Lagrange multipliers is derived. Moreover, an active controller is designed by the nonlinear decoupling method for the trajectory tracking for the system. The validity of the proposed dynamic model is verified by comparison of numerical simulation results and results obtained from the software ADAMS. And then we carry out a series of simulations in order to observe the influence of joint friction on operating a space robot with different friction models. We also study the interaction between the low-speed motion and joint friction in the process of trajectory tracking.

For solar array system, traditional modeling theories usually adopt the Cartesian coordinates to establish the dynamic equation of the system. The order of this equation is often too high and inconvenient to design control laws and the Cartesian coordinates are difficult to be measured in practice. This paper presents a modeling method for solar array system. In this method, joint coordinates of the solar panels, yoke and the spacecraft main-body are defined as the generalized variables. In this way, the dynamic equation derived here possesses lower order than those derived by other methods used before, which facilitates further control design. Moreover, the joint coordinates can be easily measured in practice. On the other hand, joint friction is an important issue to be considered. Joint friction could affect the stability and control precision of the system. Most existing studies on joint friction of solar array system are over-simplified into plane problems, and as a result, inaccuracy of friction force calculation output was incurred. In this paper, a three-dimensional revolute joint model is introduced, the calculation of joint friction is discussed in detail, and the relationship between ideal constraint force and Lagrange multipliers is derived. In addition, the control design of the solar array system is discussed and the fuzzy adaptive PD control method is used for controller design. At the end of this paper, the validity of the above studies is verified by the comparisons of numerical simulations with the ADAMS software.

Aiming to develop high performance flame-retardant epoxy resin (EP), a novel phosphorus-containing semi-aromatic polyester named poly[4,4′-bis(6-hydroxyhexyloxy)biphenyl 9,10-dihydro-10-[2,3-di(hydroxycarbonyl)propyl]-phosphaphenanthrene-10-oxide] (PBHDDP) was synthesized and employed as a multi-functional additive for EP with simultaneously flame retardation and mechanical enhancement. Appropriate thermodynamic compatibility between PBHDDP and the EP network made no phase separation occurred in the process of curing reaction. Compared with neat EP, the resultant EP thermoset containing barely 2.5 phr (2.44 wt%) of PBHDDP exhibited superior mechanical properties with 20.3% and 149% increase in tensile and impact strengths, respectively. Simultaneously, as increasing the content of PBHDDP, flame retardancy of the thermosets enhanced obviously as evidenced by the elevated anti-ignition and self-extinguishing performance, along with the reduced combustion rate and heat release. Whereas, obvious sacrifice of either transparency, glass transition temperature or thermal stability was absent. The exploration of this novel state-of-art that simultaneously improved the mechanical properties and flame retardancy of EP thermosets at a relatively low content of a single-component multi-functional additive provided a powerful basis for the technologies and potential industrial applications.

In the paper, we research on the behavior dynamics for the large-scale logistics system warehouse-out operation systematically. First, we discover that steel products warehouse-out of different warehouses in a large-scale logistics system can be characterized by burst, and the warehouse-out inter-event time follows the power-law distribution with exponents close to α = 2.5 , which differs from the two classical models proposed by Barabasi (2005) and Vazquez (2005) respectively. By analyzing the warehouse-out inter-event time distribution of the products in one certain large-scale logistics system, we further discuss burst features and mechanisms of logistics system. Additionally, we find that in population behaviors, burst features can be explained by the priority that rooted in holidays and interior task scheduling. However, warehouse-out behaviors of active individuals do not show any features of burst. Further, we find that warehouse-out quantity of steel products follows Fractal Brownian motion with the HURST exponent higher than 0.5 by means of R / S , which infers that the quantity of products in a logistics system is not only guided by prices in the present market, but also related closely to the previous quantity of warehouse-out. Based on V statistic, we compare memory length of different products in warehouses. Finally, we apply complex networks visibility graphs for further validation of fractal features in a logistics system and find that almost every visibility graph exhibits small-world and scale-free features. Both R / S and complex networks visibility graphs reinforce that the warehouse-out quantity of products in a logistics system is not a random walk process, but contains intrinsic regularities and long-term correlation between present and previous warehouse-out quantity.

A theoretical study of the complexes formed between HArF and XH 2 P (X = F, Cl, and Br) has been carried out using ab initio methods (MP2/aug-cc-pVDZ, MP2/aug-cc-pVTZ, and CCSD(T)/aug-cc-pVTZ). Three minima were found, which correspond to a hydrogen-bonded complex (I), a pnicogen-bonded complex (II), and a halogen-bonded complex (III). The pnicogen-bonded complex is the most stable, followed by the hydrogen-bonded complex, and the halogen-bonded complex is the least stable. The Ar–H bond is enhanced in FH 2 P–HArF–I complex and exhibits a blue shift, while it is weakened in ClH 2 P–HArF–I and BrH 2 P–HArF–I complexes and shows a red shift. A blue shift is also found for the distant Ar–H bond in the halogen-bonded and pnicogen-bonded complexes. These complexes have been understood with the electrostatic potentials and symmetry adapted perturbation theory (SAPT) method.

Ab initio calculations have been performed for the complexes of benzene with HArF, HKrF, and HXeF. The computed results indicate that the complexes of benzene-HArF exist in different conformations and among them those with π-hydrogen bonds are the more stable than those with C-H···F hydrogen bonds. Interestingly, the Ar-H stretching frequency is redshifted in the more stable isomer and blueshifted in the less stable form. The Ng (Ng=Ar, Kr, and Xe) atomic number dependence of the Ng-H···π and C-H···F hydrogen bonds has been explored. The result indicates that the strength of Ng-H···π and C-H···F hydrogen bonds is weakened with the increase of Ng atomic number. Natural bond orbital analysis has been performed to understand the interaction nature, frequency shift of H-Ng stretch, and dependence of Ng-H···π and C-H···F hydrogen bonds on the Ng atomic number.

Highly significant QTL for BW and abdominal fat traits on chicken chromosome 1 were reported previously in a unique F2 population. The objective of this study was to confirm and refine the QTL locations. Compared with the previous experiment, this study added 8 new families, including all the animals in the pedigree, and genotyped 9 more microsatellite markers, including 6 novel ones. Linkage analyses were performed. The results of the linkage analyses showed that the confidence intervals for BW and abdominal fat percentage were narrowed sharply to a small interval spanning 5.5 and 3.7 Mb, respectively. The results of the present study showed that using more markers and individuals could decrease the confidence interval of QTL effectively. In the current QTL region, by combining the biological knowledge of genes and the results of a microarray analysis that was performed in divergently selected lean and fat lines, several genes stood out as potential candidate genes.

This article proposes a new algorithm to improve the rate control efficiency of enhanced reverse link medium access control (RLMAC) in the code division multiple access (CDMA) Ix EV-DO release A (Rev. A) system. The new algorithm brings reverse access terminal (AT) pilot power to the RLMAC rate control procedure and makes it easier for a low pilot power user to increase its data rate when the system is slightly loaded and harder to decrease its date rate when the system is heavily loaded. Numerical results of system level simulations show that the new algorithm can bring higher system throughput, lower AT transmission power, and lower system load.

Objective To investigate the neural electrophysiological activity underlying Chinese and English Stroop tasks for Chinese-English bilinguals. Methods Event-related potentials (ERPs) were recorded in 14 Chinese bilinguals with a moderate command of English when they performed the Stroop task presented in English words and Chinese characters, respectively. Results In Chinese task version, it was found an increased positivity over bilateral front-polar regions on incongruent trials compared with congruent trials, followed by an increased negativity over fronto-central region and an increased positivity over occipital region. While in English task version, only the increased negativity was observed over fronto-central region, but with reduced amplitude and anterior distribution. Conclusion This increased negativity was proposed as an index of the resolution processes of conflicting information in the incongruent situation. The increased positivity over occipital region on Chinese incongruent trials may indicate visually rechecking effect for Chinese character.

Objective To examine and compare the synchronization of different brain regions during the Chinese and English Stroop tasks. Methods Ten native Chinese speakers with a moderate command of English participated in this study, and event-related potentials were recorded while participants performed the Stroop task. Then wavelet-based estimation of instantaneous EEG coherence was applied to investigate the synchronization of different brain regions during Stroop task. Results A greater negativity for the incongruent situation than congruent situation appeared from 350 ms to 600 ms post-stimulus onset over frontal, central, and parietal regions in Chinese Stroop task, while the negativity was absent in English Stroop task. However, not only in Chinese Stroop task but also in English Stroop task was it found significantly higher EEG coherences for the incongruent situation than congruent situation over frontal, parietal, and frontoparietal regions before 400 ms post stimulus onset at β (13–30 Hz) frequency band. Conclusion This finding indicated that wavelet-based coherence is more exquisite tool to analyze brain electro-physiological signals associated with complex cognitive task than ERP component, and that functional synchronization indexed by EEG coherence is enhanced at the earlier stage while processing the conflicting information for the incongruent stimulus.

Body weight and abdominal fat traits are complex and important economic traits that may benefit from the implementation of MAS. The objective of the current study was to identify QTL associated with BW and abdominal fat traits. The Northeast Agricultural University resource population was used in the current study. Body weight and abdominal fat weight were measured in the F2 population. A total of 369 F2 individuals produced from 4 F1 families, their parents, and F0 birds were genotyped by 23 fluorescent microsatellite markers on chromosome 1. A linkage map was constructed, and interval mapping was conducted to identify putative QTL. For BW, 10 QTL were identified at the 1% chromosome wide level, and these 10 QTL were grouped to 3 different regions; 2 QTL were identified at the 5% chromosome wide level, and these 2 QTL were grouped to 2 different regions; and 5 QTL were identified at the suggestive level, and these 5 QTL were grouped to 4 different regions. For the abdominal fat traits, 1 QTL was identified at the 1% chromosome wide level, 1 QTL was identified at the 5% chromosome wide level, and 2 QTL were identified at the suggestive level. The QTL for BW at 12 wk of age explained 13.51% of the phenotypic variance, and 2 QTL for abdominal fat weight explained 2.53 and 3.97% of the phenotypic variance, respectively. The present study identified chromosome regions harboring significant QTL affecting BW and abdominal fat traits. The results provide a useful reference for further candidate gene research and MAS for BW and abdominal fat traits.

We performed the dynamic mechanical relaxation measurements in typical metallic Zr(46.75)Ti(8.25)CU(7.5)Ni(10)Be(27.5) and Ce(70)Al(10)Cu(20) supercooled liquids close to their glass transition temperature T(g). An obvious excess wing is observed both in temperature- and frequency-dependent loss modulus curves by the calculation of the relaxation time of cc-relaxation in supercooled liquids using the Kohlrausch-Williams-Watts equation in combination with the Vogel-Fulcher-Tamman equation. The results support that the slow beta-relaxation process exists in the metallic liquids and the excess wing is the high-frequency flank of the beta-relaxation. The existence of beta-relaxation in the metallic supercooled liquids affirms that the beta-relaxation process arises from the small-scale translational motions of atoms which are hindered in its metastable atomic solid-like islands. (c) 2006 Elsevier B.V. All rights reserved.